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Moghbelli, Hassan, Abolfazl Halvaei Niasar i Ehsan Boloor Kashani. "Acoustic Noise Reduction of BLDC Motor Drive Using One-Cycle Current Control Strategy". Applied Mechanics and Materials 704 (grudzień 2014): 385–89. http://dx.doi.org/10.4028/www.scientific.net/amm.704.385.
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Torque ripple and resulted acoustic noise and vibration are the main disadvantages of brushless DC (BLDC) motor drives. In this study, One-Cycle Control (OCC) is developed for current regulation of brushless DC (BLDC) motor drive as a unified constant-frequency integration control strategy. Employing one-cycle control strategy reduces high frequency torque ripple of conventional hysteresis current controllers leading to lower acoustic noise and vibration in the drive. To enhance reliability and reducing drive cost, an improved rotor position estimation technique is implemented. OCC strategy and sensorless method are realized using a low-cost general-purpose AVR microcontroller (Atmega8). It is shown that torque ripple, acoustic noise and vibration are reduced via OCC method comparing to conventional hysteresis control strategy. Computer simulations and experimental results with a 375W, 16 poles BLDC motor, demonstrate improved behavior of developed sensorless BLDC drive operation.
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Karaarslan, Ahmet, i Ali Shaibu. "Performance Analysis and Comparison of Non-Inverting Buck-Boost Converter Using PI, OCC, and Hybrid OCC-PI Control". Journal of Electrical Technology UMY 6, nr 2 (10.11.2022): 57–66. http://dx.doi.org/10.18196/jet.v6i2.15756.
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The study compares and analyses the performance of the one-cycle control (OCC), hybrid one-cycle-proportional integral control (OCC-PI), and the conventional PI control method applied to the non-inverting buck-boost converter. The hybrid OCC-PI control method combines the OCC and PI control techniques to provide a hybrid non-linear closed-loop control technique for regulating the buck-boost converter. The MATLAB/Simulink equivalent system model was simulated with design parameter variations using a wide input voltage range of 9 – 36 V, a nominal output voltage of 28 V, and a fixed switching frequency of 250 kHz to validate the control response speed, reliability, and robustness of the proposed control technique. The simulation results due to input voltage, output voltage, and load variations were carried out whiles recording the settling time, overshoots, efficiency, output voltage, and inductor current ripples due to each applied control technique. The simulation results indicated that the Hybrid OCC-PI control provides better response speed and a lower output voltage overshoot relative to the PI. It also provides better reference voltage tracking compared to the OCC control method.
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Baldwin Immanuel, T., P. Muthukumar, C. Gnanavel, M. Rajavelan i M. Marimuthu. "Transformer less 1Φ Inverter for Grid-Connected PV Systems with an Optimized Control". International Journal of Engineering & Technology 7, nr 3.34 (1.09.2018): 217. http://dx.doi.org/10.14419/ijet.v7i3.34.18968.
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This paper investigates the transformerless single-phase inverter incorporates with the photovoltaic system along with the support of grid voltage. Solar Energy is a Non-Conventional Energy source which is mandatory for power generation due to their immeasurable parade and green pleasant nature. One-cycle control (OCC), Ruggedness and consistency which makes the interfacing with the grid easily. For grid interfacing, the inverter circuit does not need phase locked loop facility and are gradually being working for such solicitations. The strategy of the OCC inverter of one stage for solar PV applications is supported by means of a Sinusoidal Pulse Width Modulation to enhance inverter enactment at both low and high insolation levels. These factors allows the plan of a MPPT along P&O controller that pointedly progresses inverter playacting. Though, the OCC-based structures testified previous sensing of the grid voltage which slightly equalizers the strength of its characteristics, In order to dazed the restriction of prior researches, an One Cycle Control based grid-connected one-stage PV system is suggested. The sustainability of the suggested scheme is inveterate by performance simulation justification.
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Wang, Cong, Jinqi Liu, Hong Cheng, Yuan Zhuang i Zhihao Zhao. "A Modified One-Cycle Control for Vienna Rectifiers with Functionality of Input Power Factor Regulation and Input Current Distortion Mitigation". Energies 12, nr 17 (2.09.2019): 3375. http://dx.doi.org/10.3390/en12173375.
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In this paper, aiming at incorporating reactive power compensation functionality into the Vienna rectifiers, a modified one-cycle-control (MOCC) strategy is proposed by which the three-phase Vienna rectifier can be regulated in leading, lagging or unity power factors with near-sinusoidal input current waveform. First, a brief review of the working principle of the conventional OCC (COCC) strategy is conducted. Then, the MOCC strategy with the functionality of input current phase-shift control is discussed in detail. To mitigate input current distortion caused by the current phase-shift, a method whereby the signal of one phase current which is flowing in an uncontrollable region is injected into the other two phases’ current command signals is further presented. The constraints to the implementation of the MOCC scheme and the reactive power compensation capacity of the rectifier under MOCC control are analyzed as well. The proposed MOCC strategy is as easy to implement as the COCC strategy. Moreover, the MOCC strategy also preserves all other advantages of the COCC strategy, such as no phase-locked loop, no frame transformation and constant switching frequency. Finally, the theoretical analysis of the proposed MOCC strategy is fully verified by simulation and experimental results from a 1 kV·A three-phase Vienna rectifier prototype.
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Shankar, T., N. Venugopal Rao, Snigdha Gowd, Syed Tauqheer Ahmed, V. Vinod i M. Vikas Goud. "A Comparative Evaluation of the Dimensional Accuracy of Heat Polymerized Acrylic Resin Denture Base Clamped by the Conventional Method and by New-press Technique and Cured by Long Curing Cycle: An in vitro Study". Journal of Contemporary Dental Practice 13, nr 6 (2012): 842–49. http://dx.doi.org/10.5005/jp-journals-10024-1240.
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ABSTRACT Aim The aim of this study is to evaluate the dimensional accuracy of heat polymerized acrylic resin denture base clamped by the conventional method and by new-press technique and cured by long curing cycle. Materials and methods In this study, a total of 60 standardized maxillary record bases were fabricated with seven reference points as follows: • Point A Incisive papilla, • Point B and C Canine region on either side • Point E and G Midpoint of tuberosities on either side • Point F Midpoint of the line joining the two tuberosities • Point D Midpoint between the line joining A and F Group A Ten maxillary record bases were fabricated by conventional clamping method and cured by long curing cycle. Group A’ Ten maxillary record bases were fabricated by New Press or RS tension clamping method and cured by long curing cycle. The distances between the reference points, i.e. A-B, A-C, A-D, D-F, B-E, C-G, E-F, F-G, B-D, D-G, C-D, D-E of all three thermoplastic denture base plates were measured and recorded with the help of travelling microscope and were used for comparison with the measured and recorded readings of processed acrylic denture bases. The data obtained was analyzed by using the one-way analysis of variance and HSD Multiple Comparison Test. Results The overall results of the study indicate that among all the denture bases cured by the two clamping systems and the long curing cycle, group A‘ were the most dimensionally stable, followed by control group A. Conclusion The study concluded that the denture bases fabricated by the New Press method using the long curing cycle would produce the most dimensionally stable denture bases. How to cite this article Shankar T, Gowd S, Ahmed ST, Vinod V, Goud MV, Rao NV. A Comparative Evaluation of the Dimensional Accuracy of Heat Polymerized Acrylic Resin Denture Base Clamped by the Conventional Method and by New-press Technique and Cured by Long Curing Cycle: An in vitro Study. J Contemp Dent Pract 2012;13(6):842-849.
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Adelstein, David J., Yi Li, George L. Adams, Henry Wagner, Julie A. Kish, John F. Ensley, David E. Schuller i Arlene A. Forastiere. "An Intergroup Phase III Comparison of Standard Radiation Therapy and Two Schedules of Concurrent Chemoradiotherapy in Patients With Unresectable Squamous Cell Head and Neck Cancer". Journal of Clinical Oncology 21, nr 1 (1.01.2003): 92–98. http://dx.doi.org/10.1200/jco.2003.01.008.
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Purpose: The Head and Neck Intergroup conducted a phase III randomized trial to test the benefit of adding chemotherapy to radiation in patients with unresectable squamous cell head and neck cancer. Patients and Methods: Eligible patients were randomly assigned between arm A (the control), single daily fractionated radiation (70 Gy at 2 Gy/d); arm B, identical radiation therapy with concurrent bolus cisplatin, given on days 1, 22, and 43; and arm C, a split course of single daily fractionated radiation and three cycles of concurrent infusional fluorouracil and bolus cisplatin chemotherapy, 30 Gy given with the first cycle and 30 to 40 Gy given with the third cycle. Surgical resection was encouraged if possible after the second chemotherapy cycle on arm C and, if necessary, as salvage therapy on all three treatment arms. Survival data were compared between each experimental arm and the control arm using a one-sided log-rank test. Results: Between 1992 and 1999, 295 patients were entered on this trial. This did not meet the accrual goal of 362 patients and resulted in premature study closure. Grade 3 or worse toxicity occurred in 52% of patients enrolled in arm A, compared with 89% enrolled in arm B (P < .0001) and 77% enrolled in arm C (P < .001). With a median follow-up of 41 months, the 3-year projected overall survival for patients enrolled in arm A is 23%, compared with 37% for arm B (P = .014) and 27% for arm C (P = not significant). Conclusion: The addition of concurrent high-dose, single-agent cisplatin to conventional single daily fractionated radiation significantly improves survival, although it also increases toxicity. The loss of efficacy resulting from split-course radiation was not offset by either multiagent chemotherapy or the possibility of midcourse surgery.
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Yosaf, Salem, i Hasan Ozcan. "Effect of Ejector Location in Absorption Refrigeration Cycles Using Different Binary Working Fluids". International Journal of Air-Conditioning and Refrigeration 27, nr 01 (marzec 2019): 1950003. http://dx.doi.org/10.1142/s2010132519500032.
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In this study, three novel modifications of ejector-absorption refrigeration cycles (E-ARC) are investigated to evaluate the effect of ejector location on cycle performances. In the first modification (triple pressure level absorption refrigeration cycle TPL-ARC), the ejector is located at the evaporator inlet. In the second modification (double ejector absorption refrigeration cycle DE-ARC), two ejectors are used; one is located at the evaporator inlet and the other at the absorber inlet, which are coupled to each other. In the third modification (low pressure condenser absorption refrigeration cycle LPC-ARC), the steam ejector is installed at the downstream of the vapor generator discharging line. An additional flow splitter is integrated to the steam ejector outlet and part of the vapor is extracted and returned to the absorber at a pressure equal to the diffuser pressure. Effect of ejector location on thermodynamic performances are evaluated considering three different working fluids, namely ammonia–water solution (NH3–H2O), lithium bromide-water solution (H2O–LiBr), and lithium chloride–water solution (H2O–LiCl). Even though all three configurations enhance the conventional absorption refrigeration cycle (C-ARC) performances, the LPC-ARCs work at high temperature and improve the cycle performance. The TPL-ARC proves to improve the COP and exergy efficiency up to 9.14% and 7.61%, respectively, presenting the highest thermodynamic performance enhancement and lowest operating temperature.
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Lorente Rubio, Carlos, Jorge Luis García-Alcaraz, Juan Carlos Sáenz-Diez Muro, Eduardo Martínez-Cámara, Agostino Bruzzone i Julio Blanco-Fernández. "Environmental Impact Comparison of Geothermal Alternatives for Conventional Boiler Replacement". Energies 15, nr 21 (1.11.2022): 8163. http://dx.doi.org/10.3390/en15218163.
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In the transition towards a sustainable world with a “green horizon” (something that is also of great importance to the policy of energy self-sufficiency in housing and self-consumption), geothermal energy is seen as quite a feasible alternative for single-family homes. This article focuses on a comparison between the environmental impact and life cycle analysis of three alternatives and provides a base case for the replacement of a conventional type of boiler with a geothermal one for a typical house located in a Mediterranean climate. The first alternative (A) consists of a horizontal catchment system through a field of geothermal probes. The second alternative (B) is a shallow water catchment system, open type, with the return of water to a nearby river. The third option studied (C) is also a shallow water catchment system but with the water, return injected into a well downstream to the underground water flow. The study shows that alternatives A and B have the least environmental impact in most of the categories studied. The total amortization periods for the three alternatives and the base case differ by almost two years, with alternative A taking 6.99 years and alternative C costing 8.82 years.
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Zouari, Wiem, Imen Nouira El Badsi, Bassem El Badsi i Ahmed Masmoudi. "Three-Level NPC Inverter-Fed IM Drives under PTC, Minimizing the Involved Voltage Vectors and Balancing the DC Bus Capacitor Voltages". Sustainability 14, nr 20 (19.10.2022): 13522. http://dx.doi.org/10.3390/su142013522.
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The paper deals presents a comparative study of the steady-state and transient behaviors of three-level neutral-point clamped (3L-NPC) inverter-fed induction motor (IM) drives under the control of three predictive torque control (PTC) schemes: the conventional one (C-PTC) and two new strategies involving selected stator voltage vectors (SVs), namely: (SV-PTC1) and (SV-PTC2). Compared to the C-PTC, the latter enable a reduction of the number of voltage vectors as well as the weighting factors. The introduced PTCs mainly differ by the cost function, which is more simple in the case of SV-PTC2. However, SV-PTC1 allows a systematic clamping of each stator phase to the DC bus voltage, at a low level of 60 degrees, and a high level at 60 degrees per cycle, while such a clamping is arbitrary in the case of SV-PTC2. Simulations prove the higher performances of the introduced SV-PTCs over the C-PTC ones, in terms of the reduction of the current distortion and of the torque ripple. Simulation results were validated by the experiments.
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Hsieh, Min-Fu, Po-Hsun Chen, Fu-Sheng Pai i Rui-Yang Weng. "Development of Supercapacitor-Aided Hybrid Energy Storage System to Enhance Battery Life Cycle of Electric Vehicles". Sustainability 13, nr 14 (9.07.2021): 7682. http://dx.doi.org/10.3390/su13147682.
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This paper presents a C-rate control method for a battery/supercapacitor (SC) hybrid energy storage system (HESS) to enhance the life cycle of the battery in electric vehicles (EVs). The proposed HESS provides satisfactory power for dynamic movements of EVs (e.g., acceleration or braking) while keeping the battery current within a secure level to prevent it from degradation. The configurations of conventional HESSs are often complex due to the two energy storages and their current/voltage sensing involved. Therefore, in this paper, a simple current-sensing scheme is utilized and the battery is directly treated as a controlled variable to help the battery output current remain stable for different load conditions. While the proposed circuit requires only one current feedback signal, neither the SC nor load current sensors are needed, and the circuit design is thus significantly simplified. Both simulation and experimental results validated the effectiveness of the proposed HESS operating in conjunction with the motor drive system. The proposed method aims at fully utilizing recycled energy and prolonging battery lifespan.
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Hosseini Asl, S. Ali, Reza E. Rad, Arash Hejazi, YoungGun Pu i Kang-Yoon Lee. "A 64-MHz 2.15-µW/MHz On-Chip Relaxation Oscillator with 130-ppm/°C Temperature Coefficient". Electronics 12, nr 5 (27.02.2023): 1144. http://dx.doi.org/10.3390/electronics12051144.
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This paper presents a 2.15 µW/MHz at the frequency of 64 MHz relaxation oscillator with a dynamic range of frequency from 47.5 MHz to 80 MHz. To reduce the power consumption and improve energy efficiency, this work employs only one comparator and one capacitor to generate the output clock in comparison with conventional relaxation oscillator structures. A total of 50% ± 5% of the duty cycle is obtained for the output clock by implementing an auxiliary comparator. The proposed relaxation oscillator uses the output voltages of an external low-dropout (LDO) voltage and bandgap reference (BGR) for the required supply and reference voltages, respectively. Two current sources are implemented to provide the required currents for trimming the output frequency and driving the comparators. Measurement results indicate that the relaxation oscillator achieves a temperature coefficient (TC) of 130 ppm/°C over a wide temperature range from −25 °C to 135 °C at the frequency of 64 MHz. The relaxation oscillator consumes 115 µA of current at the frequency of 64 MHz under a low-dropout (LDO) voltage of 1.2 V. The proposed relaxation oscillator is analyzed and fabricated in standard 90 nm complementary metal-oxide semiconductor (CMOS) process, and the die area is 130 µm × 90 µm.
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Burns, Julie E., Olga V. Moroz, Alfred A. Antson, Cyril M. Sanders, Keith S. Wilson i Norman J. Maitland. "Expression, crystallization and preliminary X-ray analysis of the E2 transactivation domain from papillomavirus type 16". Acta Crystallographica Section D Biological Crystallography 54, nr 6 (1.11.1998): 1471–74. http://dx.doi.org/10.1107/s0907444998010889.
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The N-terminal transactivation domain of the E2 protein from human papillomavirus type 16 has been crystallized by vapour diffusion. Crystals belong to the space group P3121 (or P3221) with unit-cell dimensions a = b = 54.3, c = 155.5 Å. There is one molecule per asymmetric unit with a solvent content of 55%. Crystals diffract to at least 2.5 Å resolution and complete X-ray data to 3.4 Å have been collected on a conventional laboratory source. This 201- amino-acid domain of the E2 protein has been shown to interact functionally with both the HPV E1 protein and at least three cellular transcription factors, to fulfil its role in the control of viral transcription and replication. A knowledge of the structural basis of these multiple interactions should lead to a fuller understanding of the mechanism of action of this key regulator of the HPV life cycle.
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Klejnowska, Katarzyna, Mateusz Sydow, Rafał Michalski i Magdalena Bogacka. "Life Cycle Impacts of Recycling of Black Mass Obtained from End-Of-Life Zn-C and Alkaline Batteries Using Waelz Kiln". Energies 16, nr 1 (21.12.2022): 49. http://dx.doi.org/10.3390/en16010049.
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The utilization of end-of-life batteries (including Zn-C and alkaline batteries) is one of the areas that need to be perfected in order to provide environmental and human safety as well as to contribute to closing the material loop, as described in the EU Green Deal. The presented study shows the environmental impacts of the two selected pyrometallurgical technologies (processing of the black mass from waste Zn-C and alkaline batteries as an additive to an existing process of the recycling of steelmaking dust and treatment of the black mass as the primary waste material, both processes performed in a Waelz kiln). The presented LCA-based study of the recycling of end-of-life Zn-C and alkaline batteries focused on terrestrial ecotoxicity can be a useful tool in the process of the development of a circular economy in Europe, as it provides a multi-disciplinary overview of the most important environmental loads associated with the described recycling technologies. Therefore, the goal of the presented study was to compare the environmental performance (utilizing LCA) of two different metallurgical processes of black mass utilization, i.e., the conventional method utilizing black mass as a co-substrate and the newly developed method utilizing black mass as a primary substrate.
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Gómez, SS, P. Bravo, R. Morales, A. Romero i A. Oyarzún. "Resin Penetration in Artificial Enamel Carious Lesions after Using Sodium Hypochlorite as a Deproteinization Agent". Journal of Clinical Pediatric Dentistry 39, nr 1 (1.09.2014): 51–56. http://dx.doi.org/10.17796/jcpd.39.1.e72570275387527r.
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Objectives: To study the degree of penetration of an adhesive resin in artificial enamel carious lesions after using sodium hypochlorite as deproteinization agent. Study design: Twenty included human third-molars, extracted for surgical indication, were used. Artificial lesions were created in the buccal and lingual sides of each specimen through a cycle of demineralization-remineralization. Samples were then incubated in human saliva for 7 days at 37 ° C. After surface cleaning, lesions and the peripheral sound enamel were etched with 37% orthophosphoric acid for 20 seconds. One lesion of each specimen was treated with 5.25% sodium hypochlorite (NaOCl) for one minute. The other lesion of each specimen was used as a control. Experimental and control lesions were sealed with a fluid resin marked with Rhodamine B. Lesions were sectioned for microscopic observation by epifluorescence and polarized light. The images obtained were analyzed morphometrically. The micrometer measurements were made with ImageJ ® software. The level of significance was assessed at p<0.05. Results: The average sealant depth penetration in the control group was 94.9 ± 28.6 ?m versus 122.8 ± 25.3 μm in the experimental group. This represents Δ 20.1% significantly greater penetration when using sodium hypochlorite (p<0.001). Conclusion: The results demonstrated a significant penetration of the sealing resin when the conventional technique is complemented with the application of 5.25% sodium hypochlorite for one minute in artificial enamel carious lesions.
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Wabo Poné, J., C. F. Bilong Bilong i M. Mpoame. "In vitro nematicidal activity of extracts of Canthium mannii (Rubiaceae), on different life-cycle stages of Heligmosomoides polygyrus (Nematoda, Heligmosomatidae)". Journal of Helminthology 84, nr 2 (4.09.2009): 156–65. http://dx.doi.org/10.1017/s0022149x09990435.
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AbstractThe increasing prevalence of anthelmintic-resistant strains of helminths, drug residues in animal products and high cost of conventional anthelmintics has created an interest in studying medicinal plants as an alternative source of anthelmintic. The potential nematicidal activities of four extracts from the bark of Canthium mannii (Rubiaceae) stem were investigated in vitro. Extracts were diluted in distilled water (DW) to obtain five different concentrations (1.5, 2.0, 2.5, 3.0 and 3.5 mg/ml) and put in contact with eggs and larvae of Heligmosomoides polygyrus. The different stages of the life cycle were also put in contact with the same concentration of mebendazole (MBZ, positive control). One millilitre of each extract at different concentrations and control were added to 1 ml solution containing 30–40 eggs or 10–15 larvae (L1, L2 and L3) and distributed in different Petri dishes. The eggs and larvae were incubated at 24°C and exposure times were: 48 h for un-embryonated eggs, 6 h for embryonated eggs; 2, 4, 6 and 24 h for L1 and L2 larvae, 24–48 h for infective larvae (L3), and 5 days for the larval development test (from L1 to L3). DW and 1% dimethyl sulphoxide (DMSO) were used as placebo and DMSO control, respectively. Significant effects were obtained with three of the four extracts, and differences were observed depending on the parasite stage. Cold water extract (CWE), hot water extract (HWE) and ethanol extract (ETE) inhibited embryonic development (40, 45 and 10%) and hatching of embryonated eggs (40, 85 and 80%), respectively, at 3.5 mg/ml. Only ETE killed L1 (97.18%) and L2 (92.68%) larvae of H. polygyrus after 24 h at 3.5 mg/ml and drastically reduced the production rate (6% at 3.0 and 3.5 mg/ml) of infective larvae (L3) after 5 days of incubation compared to other extracts (P < 0.05). However, the infective larvae of H. polygyrus were resistant to the effect of each of the tested products (extracts and mebendazole). These in vitro results suggested that extracts of C. mannii, used by traditional healers in Dschang, Western Region of Cameroon (Central Africa) to cure intestinal helminthiasis and abdominal pains of their patients, possess nematicidal properties. The active principles responsible for the activity could be secondary metabolites such as alkaloids and saponins present in the extracts. It is suggested that further experiments incorporating in vivo purification of extracts and toxicological investigations should be carried out.
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Galic, Marija, Darija Bilandzija i Zeljka Zgorelec. "Influence of Long-Term Soil Management Practices on Carbon Emissions from Corn (Zea mays L.) Production in Northeast Croatia". Agronomy 13, nr 8 (2.08.2023): 2051. http://dx.doi.org/10.3390/agronomy13082051.
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Sustainable management of agricultural resources is needed to meet people’s increasing demands for food, fiber and energy while maintaining the quality of the environment and protecting natural resources. With the rapid growth of agriculture and the mechanization of farming, the agricultural sector has become one of the main contributors to the increase in CO2 emissions and other greenhouse gases in the world. Therefore, the aim of this study was to determine the effect, dependence and correlations of CO2 in soil with native vegetation (presence/absence, corn yield) and climatic conditions (soil temperature and moisture) during three years of measurements under different management practices in a classical conventional agroecosystem. This research contains four different treatments: control treatment (CT), dolomite/organic fertilization (DOL/OF), mineral fertilization (MF) and black fallow (BF). During the investigated period, the average overall C-CO2 flux ranged from 7.98 kg ha−1 day−1 on bare soil to 16.26 kg ha−1 day−1 on soil treated with mineral fertilization. No statistically significant difference was observed among different fertilization treatments, except in 2013 and 2015 when comparing different fertilization treatments to bare soil. In all three years, there was a positive correlation between average C-CO2 fluxes and soil temperature. Additionally, in 2013 and 2017, there was a positive correlation between average C-CO2 fluxes and soil moisture, while a negative correlation was observed in 2015. Obtained values of crop yield ranged from 0.89 t ha−1 in the control treatment (in 2015) to 14.81 t ha−1 in the treatment with mineral fertilization (in 2017). Growing global concern about the effects of climate change calls for intensive research on the carbon cycle, and these results will contribute to the understanding of carbon transformation in different crops and soil management practices.
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Melas, Anastasios, Tommaso Selleri, Jacopo Franzetti, Christian Ferrarese, Ricardo Suarez-Bertoa i Barouch Giechaskiel. "On-Road and Laboratory Emissions from Three Gasoline Plug-In Hybrid Vehicles-Part 2: Solid Particle Number Emissions". Energies 15, nr 14 (20.07.2022): 5266. http://dx.doi.org/10.3390/en15145266.
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Plug-in hybrid electric vehicles (PHEVs) are a promising technology for reducing the tailpipe emissions of CO2 as well as air pollutants, especially in urban environments. However, several studies raise questions over their after-treatment exhaust efficiency when their internal combustion engine (ICE) ignites. The rationale is the high ICE load during the cold start in combination with the cold conditions of the after-treatment devices. In this study, we measured the solid particle number (SPN) emissions of two Euro 6d and one Euro 6d-TEMP gasoline direct injection (GDI) PHEVs (electric range 52–61 km) all equipped with a gasoline particulate filter, in the laboratory and on-road with different states of charge of the rechargeable electric energy storage system (REESS) and ambient temperatures. All vehicles met the regulation limits but it was observed that, even for fully charged REESS, when the ICE ignited SPN emissions were similar or even higher in some cases compared to the operation of these vehicles solely with their ICE (discharged REESS) and also when compared to conventional GDI vehicles. On-road SPN emission rate spikes during the first 30 s after a cold start were, on average, 2 to 15 times higher with charged compared to discharged REESS due to higher SPN concentrations and exhaust flow rates. For one vehicle in the laboratory under identical driving conditions, the ICE ignition at high load resulted in 10-times-higher SPN emission rate spikes at cold-start compared to hot-start. At −10 °C, for all tested vehicles, the ICE ignited at the beginning of the cycle even when the REESS was fully charged, and SPN emissions increased from 30% to 80% compared to the cycle at 23 °C in which the ICE ignited. The concentration of particles below 23 nm, which is the currently regulated lower particle size, was low (≤18%), showing that particles larger than 23 nm were mainly emitted irrespective of cold or hot engine operation and ambient temperature.
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Silva, Carla, Patricia Moniz, Ana Cristina Oliveira, Samuela Vercelli, Alberto Reis i Teresa Lopes da Silva. "Cascading Crypthecodinium cohnii Biorefinery: Global Warming Potential and Techno-Economic Assessment". Energies 15, nr 10 (20.05.2022): 3784. http://dx.doi.org/10.3390/en15103784.
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Prior to the commissioning of a new industrial biorefinery it is deemed necessary to evaluate if the new project will be beneficial or detrimental to climate change, one of the main drivers for the sustainable development goals (SDG) of the United Nations. In particular, how SDG 7, Clean and Efficient Energy, SDG 3, Good Health and Well Being, SDG 9, Industry Innovation and Infrastructure, and SDG 12, Responsible Production and Consumption, would engage in a new biorefinery design, beneficial to climate change, i.e., fostering SDG 13, Climate Action. This study uses life cycle assessment methodology (LCA) to delve in detail into the Global Warming Impact category, project scenario GHG savings, using a conventional and a dynamic emission flux approach until 2060 (30-year lifetime). Water, heat and electricity circularity are in place by using a water recirculation process and a combined heat and power unit (CHP). A new historical approach to derive low and higher-end commodity prices (chemicals, electricity, heat, jet/maritime fuel, DHA, N-fertilizer) is used for the calculation of the economic indicators: Return of investment (ROI) and inflation-adjusted return (IAR), based upon the consumer price index (CPI). Main conclusions are: supercritical fluid extraction is the hotspot of energy consumption; C. cohnii bio-oil without DHA has higher sulfur concentration than crude oil based jet fuel requiring desulfurization, however the sulfur levels are compatible with maritime fuels; starting its operation in 2030, by 2100 an overall GHG savings of 73% (conventional LCA approach) or 85% (dynamic LCA approach) is projected; economic feasibility for oil productivity and content of 0.14 g/L/h and 27% (w/w) oil content, respectively (of which 31% is DHA), occurs for DHA-cost 100 times higher than reference fish oil based DHA; however future genetic engineering achieving 0.4 g/L/h and 70% (w/w) oil content (of which 31% is DHA), reduces the threshold to 20 times higher cost than reference fish oil based DHA; N-fertilizer, district heating and jet fuel may have similar values then their fossil counterparts.
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Pranckietienė, Irena, Kęstutis Navickas, Kęstutis Venslauskas, Darija Jodaugienė, Egidijus Buivydas, Bronius Žalys i Ilona Vagusevičienė. "The Effect of Digestate from Liquid Cow Manure on Spring Wheat Chlorophyll Content, Soil Properties, and Risk of Leaching". Agronomy 13, nr 3 (22.02.2023): 626. http://dx.doi.org/10.3390/agronomy13030626.
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Biogas production from manure and other organic matter, or combinations thereof, is part of the circular economy, and the use of the digestate from biogas production for plant nutrition and thus for soil fertility restoration and organic carbon (C) sequestration completes the circular economy cycle. The use of digestate from biogas production in agriculture is one of the sustainable ways to manage manure or organic waste, an alternative to conventional chemical fertilizers, and a means to achieve the objectives of the European Green Deal. To this end, two two-factor pot experiments were carried out in 2019–2020. Factor A—1. Control (without fertilization), 2. Liquid cow manure 170 kg ha−1 N (N170), 3. Digested manure 170 kg ha−1 N (N170), 4. Digested manure 140 kg ha−1 N (N140), 5. Digested manure 110 kg ha−1 N (N110); Factor B—1. Plants not cultivated, 2. Plants cultivated. The experiments determined the effect of digestate on the changes in soil nitrate (NO3-N), ammonium (NH4-N) and mineral (NO3-N + NH4-N) nitrogen, and available phosphorus (P2O5) and potassium (K2O) in the soil without plants as well as with plants cultivated and evaluated the risk of migration of macronutrients into deeper soil layers. The results showed that the application of the highest allowed rates under the Nitrates Directive (N170) and N140 digestate is accompanied by the addition of high levels of ammonium (NH4-N) nitrogen, which alters the balance of ammonium (NH4-N) and nitrate (NO3-N) nitrogen in the soil, and the extent of their migration to the deeper layers. These results suggest that the application of digestate to agricultural land enhances the migration of nitrogen and, in phosphorus-rich soils, of phosphorus (PO4-P) compounds to deeper layers (>25 cm). In order to achieve environmental objectives, digestate rates should be based on the agrochemical properties of the soil and the needs of the plants and should not exceed 65% of the nitrogen needed by the plants from mineral fertilizers.
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Gopalakrishnapillai, Anilkumar, Allison Kaeding, Christoph Schatz, Anette Sommer, Soheil Meshinchi, E. Anders Kolb i Sonali Barwe. "In Vivo Evaluation of Mesothelin As a Therapeutic Target in Pediatric Acute Myeloid Leukemia". Blood 134, Supplement_1 (13.11.2019): 1370. http://dx.doi.org/10.1182/blood-2019-123794.
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Pediatric acute myeloid leukemia (AML) continues to have a cure rate of only 50% despite the use of highly intensive cytotoxic chemotherapy. Transcriptome sequencing of several AML samples by the NCI/COG TARGET AML Initiative identified mesothelin (MSLN) to be highly overexpressed in about one-third of pediatric AML (Tarlock et al., Blood, 128:2873, 2016). Because MSLN is not expressed in normal bone marrow samples (Fan et al., Blood, 130:3792, 2017) and only to a low level in other human organs and tissues, MSLN is an attractive therapeutic target for pediatric AML (Kaeding et al., Blood, 130:2641, 2017). The anti-MSLN antibody-drug conjugate (ADC) anetumab ravtansine (BAY 94-9343) generated by conjugating MSLN-antibody with tubulin inhibitor DM4 (Meso-ADC), and isotype control antibody conjugated with the same drug (Iso-ADC) were used to evaluate the efficacy of MSLN targeting in vivo. MSLN-overexpressing K562 (K562-MSLN) CML cells and MV4;11 (MV4;11-MSLN) AML cells were generated by lentiviral transduction of MSLN cDNA. Cell line-derived xenografts (CDX) were created by injecting the MSLN-transduced or parental (MSLN-) cells into NSG-SGM3 mice via the tail vein. Mice were randomly assigned to treatment groups when the median percentage of human cells in mouse peripheral blood was greater than 0.5%. K562-MSLN CDX mice treated with Meso-ADC (5 mg/Kg Q3dx3, i.v.) survived a median of 46 days longer than those treated with Iso-ADC (P=0.0011) and significantly longer than comparison groups, including K562-MSLN CDX mice treated with daunorubicin and Ara-C (DA, P=0.0008) or untreated (P=0.0018) (Fig. 1A). Median survival of K562 CDX mice treated with Meso-ADC, Iso-ADC, or untreated was similar (Fig. 1B). MV4;11-MSLN CDX mice treated with Meso-ADC exhibited complete remission and remained disease-free at 1 year post cell injection, with AML cell burden remaining <0.1% throughout the study period (Fig. 1C). In contrast, MV;11-MSLN CDX mice treated with Iso-ADC or untreated succumbed to disease at 72 and 38 days, respectively. Taken together, these results indicate that Meso-ADC was efficacious in reducing leukemia burden, and this effect required MSLN expression in target cells. We have generated a panel of patient-derived xenograft (PDX) lines by transplanting and serially propagating primary pediatric AML samples into NSG-SGM3 mice. The efficacy of Meso-ADC was also evaluated in a systemic PDX model using a MSLN+ PDX line (NTPL-146). NTPL-146 PDX mice treated with Meso-ADC (5 mg/Kg, Q3dx3 -x2 cycles) survived a median of 50 days longer than those treated with Iso-ADC (P=0.0018, Fig. 1D, arrows indicate time when each treatment cycle was initiated). In an independent experiment with NTPL-146 PDX mice, a survival benefit of Meso-ADC treatment over no treatment was observed after 1 cycle of Meso-ADC treatment (5 mg/Kg, Q3dx3, P=0.0019, Fig. 1E). Additionally, a combination therapy strategy with daunorubicin and Ara-C followed by Meso-ADC (DA -> Meso-ADC) resulted in improved median survival over Meso-ADC (P=0.0027) or DA treatment alone (P=0.0018) (Fig. 1E). The disseminated MSLN+ leukemia mouse models described herein support MSLN-targeted antibody-drug conjugate as a potential treatment strategy in MSLN+ AML. Furthermore, we provide the first in vivo demonstration of synergy between MSLN-targeted therapy and conventional chemotherapy in MSLN+ AML, warranting additional investigation to validate and optimize novel strategies for combination therapy. Figure 1 Disclosures Kaeding: Celgene: Employment. Schatz:Bayer AG: Employment. Sommer:Bayer AG: Employment, Equity Ownership.
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Xu, Weiming, Christine Kang, Mercedes Delgado, Sophie M. Perrin-Ninkovic, Patrick W. Papa, Jennifer R. Riggs, John Sapienza i in. "A Novel mTOR Kinase Inhibitor Causes Growth Inhibition, Cell Cycle Arrest, Apoptosis and Autophagic Cell Death in Mantle Cell Lymphoma Cell Lines: A Distinct Profile from Rapamycin." Blood 112, nr 11 (16.11.2008): 1579. http://dx.doi.org/10.1182/blood.v112.11.1579.1579.
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Abstract Mantle cell lymphoma (MCL) is a distinct sub-type non-Hodgkin lymphoma characterized by overexpression of cyclin D1 (CCND1) in 95% of patients due to the cytogenetic change of chromosome translocation t(11;14) (q13;q32). It remains one of the most challenging lymphomas associated with shorter response duration to conventional chemotherapy as well as continuous relapses and refractory to current drugs. However, dysregulation of cyclin D1 biology alone is insufficient to develop MCL. The emerging data suggest that the mammalian target of rapamycin (mTOR) plays a crucial role in the proper transmission of proliferative and anti-apoptotic signals through the PI3K/AKT pathway that makes it an attractive therapeutic target for hematological malignances including mantle cell lymphoma. As a single agent, rapamycin analogs such as temsirolimus (CCI-779) achieved 38% overall response rate in heavily pretreated MCL and prolonged progression free survival (PFS) in relapsed and refractory mantle cell lymphoma (4.8 months in temsirolimus vs. 1.9 months in investigator’s choice, ASCO 2008). mTOR regulates two distinct complexes TORC1 and TORC2. TORC1 complex is involved in cell cycle regulation by phosphorylating p70S6K and 4E-BP1, two molecules that are important for translational control of cyclin D1 and c-myc as well as ribosomal biogenesis whereas TORC2 complex mainly regulates phospho- AKT serine 473 leading to cell survival and proliferation. mTOR kinase also negatively regulates autophagy, a process of cellular bulk protein degradation by fusion to lysosomes upon the nutrient deprivation. We have developed mTOR kinase selective inhibitors which exhibit distinct biological profile from rapamycin in many cancer cell lines. Here we demonstrate that a selective mTOR kinase inhibitor displays potent anti-proliferative activity in JeKo-1 and Mino cells associated with decreased phosphorylation of S6, p70S6K, AKT S473, 4E-BP1 as well as decreased cyclin D1 levels leading to G1 arrest. The inhibitor also promotes autophagic cell death at 72h and 96h post-treatment. Furthermore a selective mTOR kinase inhibitor but not rapamycin induces a significant apoptosis in JeKo-1 and Mino cells. The observed apoptosis is correlated with caspases mediated PARP cleavage as well as inhibition of anti-apoptotic protein Mcl-1, suggesting TORC2/AKT S473 complex may provide survival signaling for mantle cell lymphoma. A timecourse study demonstrated that JeKo-1 and Mino cells undergo apoptosis at 24h and 48h followed by significant autophagic cell death at 72h and 96h in a dose dependent manner when exposed to our mTOR kinase inhibitor. In conclusion, mTOR kinase inhibitors are able to induce G1 cell cycle arrest, caspase-dependent apoptosis and autophagic cell death that contribute to the anti-tumor activity. Therefore it may provide a powerful alternative targeted therapy for mantle cell lymphoma.
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Sermsuk, Maytungkorn, Yanin Sukjai, Montri Wiboonrat i Kunlanan Kiatkittipong. "Utilising Cold Energy from Liquefied Natural Gas (LNG) to Reduce the Electricity Cost of Data Centres". Energies 14, nr 19 (1.10.2021): 6269. http://dx.doi.org/10.3390/en14196269.
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The Office of the National Broadcasting and Telecommunications Commission has reported that, from 2014 to 2018, Thailand’s internet usage has grown six-fold to 3.3 million terabytes per annum. This market trend highlights one of the policies of Thailand 4.0, with the aim of making Thailand a hub for information transfer in ASEAN. As a result, there will be a massive demand growth for data storage facilities in the near future. Data centres are regarded as the brain and heart of the digital industry and are essential for facilitating businesses in organising, processing, storing and disseminating large amounts of data. As the energy demand for equipment cooling contributes to over 37% of the total energy consumption, the data centres of the world’s leading companies, such as Amazon, Google, Microsoft and Facebook, are generally located in cold climate zones, such as Iceland, in order to reduce operating costs for cooling. Due to this reason, the possibility of data centres in Thailand is limited. Beneficially, PTTLNG, as the first liquified natural gas (LNG) terminal in Thailand, has processed the import, receiving, storage and regasification of LNG. The high abundance of cold energy inherently presented in LNG is normally lost to the surroundings during regasification. Presently, PTTLNG’s LNG receiving terminal utilises a heat exchanger with propane as an intermediate fluid to transfer cold energy from LNG to water. This cold energy, in the form of cold water, is then used in several projects within the LNG receiving terminal: (1) production of electricity via an organic Rankine cycle capacity of 5 MWh; (2) cooling the air inlet of gas turbine generators to increase the generator efficiency; (3) replacing refrigerant heating, ventilation and air conditioning systems within buildings; (4) development of winter plantations with precision agriculture to replace imported products. Therefore, this study focuses on the potential and future use for LNG cold energy by performing a thermodynamic and economic analysis of the use of LNG cold energy as a source to produce cold water at 7 °C, with the total cold energy of 27.77 to 34.15 MW or 7934 t to 9757 t of refrigeration depending on the target pressure of the natural gas to replace the conventional cooling system of data centres. This research has the potential to reduce the cooling operation costs of data centres by more than USD 9.87 million per annum as well as CO2 emissions by 34,772 t per annum. In an economic study, this research could lead to a payback period of 7 years with IRR 13% for the LNG receiving terminal and a payback period of 2.21 years with IRR 45% for digital companies.
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Benzi, Janaina Galvão, César Rogério Pucci, Maiara Rodrigues Freitas, Priscila Christiane Suzy Liporoni i Rayssa Ferreira Zanatta. "Bonding Performance for Repairs Using Bulk Fill and Conventional Methacrylate Composites". International Journal of Dentistry 2021 (16.12.2021): 1–8. http://dx.doi.org/10.1155/2021/2935507.
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This study compared the bond strength of a composite repair made with a bulk fill composite and a conventional one using different surface treatments. Specimens were prepared as truncated cones (bases: 4 mm × 2 mm, height: 4 mm) using a bulk fill (OBFa: Filtek One) or a conventional resin (FTKa: Filtek Z250) (n = 66). They were artificially aged (10,000 cycles, 5°C–55°C, 30 sec) and subdivided according to surface treatments: NT—no treatment (control), Abr—abrasion with a diamond tip, and sand—sandblasting with aluminum oxide (50 μm). Treatments were performed over the smaller diameter surface, followed by adhesive (Scothbond Universal) application. A new specimen with similar dimensions was constructed over it using either the OBF or the FTK, totaling 12 groups (n = 11). Bond strength was assessed by tensile test. The data were submitted to two-way ANOVA separately for OBFa and FTKa, followed by Tukey’s test ( p < 0.05 ). For the aged OBFa groups, there was significant differences for composite type and surface treatment, with higher values of bond strength when repaired with the same material (OBFa/OBF > OBFa/FTK), and sandblasting and bur abrasion presented higher values compared to the control group (NT). For the aged FTKa groups, there were no differences for the composite or surface treatment. Therefore, the bulk fill resin composite tested present better repair performance when the same composite was used, while the conventional resin composite was less influenced by the material and the surface treatment performed.
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Corsetti, Maria Teresa, Flavia Salvi, Sonia Perticone, Bernardino Allione, Anna Baraldi, Alessandro Bellora, Lorella De Paoli i in. "Hematological Improvement in AML/RAEB Elderly Patients Treated with Valproic Acid and Low-Dose ARA-C". Blood 112, nr 11 (16.11.2008): 2971. http://dx.doi.org/10.1182/blood.v112.11.2971.2971.
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Abstract Histone deacetilase inhibitors (HDCAi) have been shown to modulate gene expression with pro-differentiative effects. Valproic acid (VPA) has HDCAi activity and synergizes with Ara-C to differentiate AML blasts in vitro. VPA is orally applicable and has a low toxicity prophile. We tried to assess the therapeutic activity of VPA in combination with low-dose Ara-C in elderly/frail AML/RAEB patients. We enrolled in this study 31 patients with Myeloid Pathologies. Fifteen pts had diagnosis of oligoblastic AML (M0:2, M1: 7, M2: 1, M4:1, M5: 4); 13 patients had RAEB (RAEB 1: 2, RAEB 2: 11) with the following IPSS: int-1=2, int-2= 2, high= 6. Three other patients had progression from previous MPS (1 from ET, 2 from LMMC). Median age was 70 yrs (range: 53 to 84). Median time from Diagnosis to treatment was 15 months (range 1 to 79). Clinical status at start of protocol was: at Diagnosis = 13 pts, Resistant after induction =6 pts, Relapsed after CR =11 pts, Relapsed after allogeneic transplant =1 pt). All patients were excluded from conventional chemotherapy for age and multiple comorbidities. In 27 out of 31, these comorbidities required therapy or periodic controls (grade 3), other 2 pts had one of G4 grade (life-threatening). Thirteen patients were defined “frail” because they presented 3 of G3 comorbidities or at least a G4 one. Twenty-nine pts were evaluated for autosufficiency with ADL score, 5 of them didn’t reach the score of 6, showing impairment in their autosufficiency. Assessing functional autonomy, IADL score showed deficiency in 17 of 29 patients. In our protocol, VPA was administered in continuum to reach serum concentration of 50–100μg/ml. Ara-C was given in cycles of 8 days, 40 mg/day. Ammonium and valproic acid serum level was routinely checked. Bone marrow examination was done at the enrollement in the study, after sixth cycle of Ara-C and/or if improvement of blood counts were observed. In two patients that were in CR at the end of sixth cycle, VPA was maintained; other six cycles of Ara-C were given monthly and thereafter every third month until relapse. Six patients received the treatment for at least 6 cycles, the other patients had a median of 2 cycles, (range 1 to 4). Ten patients are still in treatment, 17 dropped out for progression/death, one patient underwent reduced intensity allotransplant while in remission. From the start of protocol, median overall survival was 4 mths, range 1 to 33 mths. Fifteen pts are alive now. Overall, 11 of 31 patients (35%) had hematological improvement (according to IWG, 2008), including 7 CR (22%) with clearing of blasts in the marrow and normalization of blood counts. The median cycle of improvement was 2 (range 1 to 4) and the median duration of improvement was 2 months (range 1 to 23 months), including two pts that lasted in CR for 10 and 23 months; 3 pts are still in CR at 5,8 and 10 mths from the starting of response, one patient is in Hematological Improvenment at 2 mths. Hematological toxicity requiring platelet transfusion was seen in 17 patients, while 10 pts required red cell transfusion. Transient hyperammoniemia was seen in one patient; liver toxicity in another patient. Neutropenia-related infections were seen in 3 pts. Adding VPA to low-dose Ara-C, some complete responses and some improvements in peripheral cytopenias can be achieved without a significant increase in toxicity. Therefore this therapeutic protocol is feasible for elderly/frail oligoblastic AML/RAEB patients who cannot have aggressive therapy.
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Kirschman, Randall K., Witold M. Sokolowski i Elizabeth A. Kolawa. "Die Attachment for −120°C to +20°C Thermal Cycling of Microelectronics for Future Mars Rovers—An Overview1". Journal of Electronic Packaging 123, nr 2 (20.10.2000): 105–11. http://dx.doi.org/10.1115/1.1347996.
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Active thermal control for electronics on Mars rovers imposes a serious penalty in weight, volume, power consumption, and reliability. Thus, we propose that thermal control be eliminated for future rovers. From a functional standpoint there is no reason that the electronics could not operate over the entire temperature range of the Martian environment, which can vary from a low of ≈−90°C to a high of ≈+20°C during the Martian night and day. The upper end of this range is well within that for conventional electronics. Although the lower end is considerably below that for which conventional—even high-reliability—electronics is designed or tested, it is well established that electronic devices can operate to such low temperatures. The primary concern is reliability of the overall electronic system, especially in regard to the numerous daily temperature cycles that it would experience over the duration of a mission on Mars. Accordingly, key reliability issues have been identified for elimination of thermal control on future Mars rovers. One of these is attachment of semiconductor die onto substrates and into packages. Die attachment is critical since it forms a mechanical, thermal, and electrical interface between the electronic device and the substrate or package. This paper summarizes our initial investigation of existing information related to this issue, in order to form an opinion whether die attachment techniques exist, or could be developed with reasonable effort, to withstand the Mars thermal environment for a mission duration of approximately one earth year. Our conclusion, from a review of literature and personal contacts, is that die attachment can be made sufficiently reliable to satisfy the requirements of future Mars rovers. Moreover, it appears that there are several possible techniques from which to choose and that the requirements could be met by judicious selection from existing methods using hard solders, soft solders, or organic adhesives. Thus, die attachment does not appear to be a roadblock to eliminating thermal control for rover electronics. We recommend that this be further investigated and verified for the specific hardware and thermal conditions appropriate to Mars rovers.
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Fagerlund, Annette, Even Heir, Trond Møretrø i Solveig Langsrud. "Listeria Monocytogenes Biofilm Removal Using Different Commercial Cleaning Agents". Molecules 25, nr 4 (12.02.2020): 792. http://dx.doi.org/10.3390/molecules25040792.
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Effective cleaning and disinfection (C&D) is pivotal for the control of Listeria monocytogenes in food processing environments. Bacteria in biofilms are protected from biocidal action, and effective strategies for the prevention and removal of biofilms are needed. In this study, different C&D biofilm control strategies on pre-formed L. monocytogenes biofilms on a conveyor belt material were evaluated and compared to the effect of a conventional chlorinated, alkaline cleaner (agent A). Bacterial reductions up to 1.8 log were obtained in biofilms exposed to daily C&D cycles with normal user concentrations of alkaline, acidic, or enzymatic cleaning agents, followed by disinfection using peracetic acid. No significant differences in bactericidal effects between the treatments were observed. Seven-day-old biofilms were more tolerant to C&D than four-day-old biofilms. Attempts to optimize biofilm eradication protocols for four alkaline, two acidic, and one enzymatic cleaning agent, in accordance with the manufacturers’ recommendations, were evaluated. Increased concentrations, the number of subsequent treatments, the exposure times, and the temperatures of the C&D agents provided between 4.0 and >5.5 log reductions in colony forming units (CFU) for seven-day-old L. monocytogenes biofilms. Enhanced protocols of conventional and enzymatic C&D protocols have the potential for improved biofilm control, although further optimizations and evaluations are needed.
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Kato, H., M. Anzai, T. Mitani, M. Morita, Y. Nishiyama, A. Nakao, K. Kondo i in. "62 RECOVERY OF CELL NUCLEI FROM 15 000-YEAR-OLD MAMMOTH TISSUES AND INJECTION INTO MOUSE ENUCLEATED MATURED OOCYTES". Reproduction, Fertility and Development 22, nr 1 (2010): 189. http://dx.doi.org/10.1071/rdv22n1ab62.
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Since the report of “Dolly” (Wilmut et al. 1997 Nature 385, 810-813), cloned animals have been successfully produced by somatic cell nuclear transfer (SCNT). In those reports, cultured or fresh cells were mainly used as nuclear donor cells in SCNT. Meanwhile, there was a report of the birth of offspring by SCNT with the nuclear donor cell derived from frozen whole body kept at -20°C for 16 years without cryoprotectant (Wakayama et al. 2008 Proc. Natl. Acad. Sci. USA 105, 17 318-17 322). This report suggests that if tissues or cells are cryopreserved postmortem without cryoprotectant, resurrection of the postmortem animal individual might be possible by SCNT. Furthermore, in cases of extinct or endangered species, it is difficult to use oocytes derived from same species as the recipient cytoplasm. However, there was a report of the birth of offspring by SCNT with oocytes derived from closely related species (Lanza et al. 2000 Cloning 2, 79-90). This result suggests that if oocytes from closely related species are available as the recipient cytoplasm, it would be possible to resurrect extinct or endangered species by SCNT. Woolly mammoth (Mammuthus primigenius) is a famous animal that existed during the ice ages and became extinct at the end of the last ice age. Its relics have been excavated from permafrost. Recently, the prospect of the resurrection of woolly mammoth by SCNT has heightened. However, even if the soft tissue of the woolly mammoth is excavated, it is not clear whether its cell nuclei retain their biological characteristics for more than several thousand years. In this study, we recovered cell nuclei from 15 000-year-old mammoth tissues and injected them into mouse enucleated matured oocytes as the nuclear donor in SCNT. Frozen mammoth legs were excavated from Northeast Siberian permafrost at the point of 71°34′56.9″ N and 141°37′37.6″ E. The conventional radiocarbon age of the sample after 13C correction was 13 100 to 12800 BC or 12400 to 11 800 BC. Cell nucleus-like structures were successfully recovered from skin and muscle tissues. Those nuclei were then injected into enucleated BDF1 mouse oocytes, and more than half of the injected oocytes were able to survive (67%; 12/18 for oocytes injected with skin-derived nucleus, 55%; 72/131 for oocytes injected with muscle-derived nucleus and 33%; 26/80 for oocytes injected with frozen-thawed mouse bone marrow-derived nucleus as the control group). Injected nuclei were not taken apart and retained their nuclear structure. Those oocytes did not show disappearance of nuclear membrane or premature chromosome condensation at 1 h after injection and did not form pronuclear-like structures at 7 h after injection. Because one-half of the oocytes injected with nuclei derived from frozen-thawed mouse bone marrow cells were able to form pronuclear-like structures (46%; 12/26), it might be possible to promote the cell cycle of nuclei from ancient animal tissues by suitable pretreatment in SCNT. This is the first report of SCNT with nuclei derived from mammoth tissues. This study was funded in part by Gifu Prefecture, Japan.
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Larsson, Connie A., Kensuke Kojima, Yong Wang, Nicholas Navin, Miguel Gallardo, Daniel Primo, Jose L. Rojas i in. "BET Bromodomain Inhibition Reduces Leukemic Burden and Prolongs Survival In The Eμ-TCL1 Transgenic Mouse Model Of Chronic Lymphocytic Leukemia (CLL) Independent Of TP53 Mutation Status". Blood 122, nr 21 (15.11.2013): 876. http://dx.doi.org/10.1182/blood.v122.21.876.876.
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Abstract Introduction Inhibition of Brd4, a bromodomain and extra-terminal (BET) protein, results in antiproliferative effects and terminal differentiation in the MYC-driven B-cell malignancies multiple myeloma and Burkitt's lymphoma by selectively repressing MYC. Elevated MYC expression correlates with progression of B-cell chronic lymphocytic leukemia (B-CLL) marking Brd4 as a potential therapeutic target. 17p deletion or somatic TP53 mutations are the poorest prognostic factors in B-CLL, resulting refractoriness to conventional therapy. The recent identification of a Brd4-interacting protein as a validated target in CLL led us to evaluate the potential of BET inhibition, using jq1, for the treatment of B-CLL. Results Jq1 remarkably reduced proliferation of the immortalized human B-CLL cell lines, Mec-1, Mec-2, and WaC3 (IC50 values: 1.12, 0.68, and 0.64 μM, respectively). These results were validated in 13 frozen and 7 fresh primary whole peripheral blood B-CLL samples (median EC50 0.66 μM [range, 0.051 to 2.169 μM]) using a FACS-based proprietary platform (Vivia Biothech). Eμ-TCL1 (n=13) & Eμ-TCL1:p53R172H/+ (n=9) mice treated with intraperitoneal (IP) injections of jq1 at 50 mg/kg/day for 21 consecutive days had a significant reduction in lymphocytes and white blood cells (WBC) (with excellent tolerance and no off-target effects on hemoglobin level or platelet counts) compared to vehicle-treated mice. The median lymphocyte count at baseline and after 2 weeks of jq1 therapy was 13.4 & 5.92 x10^3/μL (p=0.008) for Eμ-TCL1 mice and 13.2 & 7.2 x10^3/μL (p=0.009) for Eμ-TCL1:p53R172H/+ mice. jq1 therapy significantly prolonged survival in both Eμ-TCL1 (428 vs 377 days, p=0.05) and Eμ-TCL1:p53R172H/+ (382.5 vs 300 days, p=0.0003) mice compared to mice receiving vehicle. FACs analysis was performed on blood taken from Eμ-TCL1 (n=5) and Eμ-TCL1:p53R172H/+ (n=6) mice at baseline and after 7 daily IP jq1 doses. Eμ-TCL1:p53R172H/+ mice showed a significant reduction in CD5+/CD19+ lymphocytes (mean difference, 14.37 [95% CI, 2.4 to 26.3]; p=0.03), which was not observed in Eμ-TCL1 mice. Cell cycle analysis of cultured Eμ-TCL1 splenocytes treated with jq1 showed a significant increase (p<0.0005) in the number of sub-G1 cells compared to untreated splenocytes, regardless of p53 status. Sensitivity against fludarabine was also tested in these samples and we show that 10μM fludarabine did not elicit significant changes in the number of cells in sub-G1 compared to untreated cells but a significant difference (p=0.009) was observed between splenocytes treated with 10μM fludarabine and 1μM jq1. In depth analyses of RNA sequencing data of splenocytes from 10 matched-pairs samples (5 Eμ-TCL1 & 5 Eμ-TCL1:p53R172H/+) treated in culture with 0 or 1μM jq1 for 24 hours are currently underway to identify BET targets in B-CLL, but preliminary gene expression analysis reveal that the sensitivity of B-CLL to BET inhibition is not Myc-dependent despite elevated Myc levels. Notably, c-Fos was one of the most significant differentially expressed genes, regardless of p53 status. Interestingly, AP-1 complex, a heterodimer of c-Fos and c-Jun, is inhibited by direct interaction with Tcl-1. We are currently validating these findings in additional samples and performing functional assays to gain a better understanding of BET targets in B-CLL. Conclusion BET bromodomain inhibition markedly reduced proliferation in both human and mouse B-CLL samples. Furthermore, the loss of wild-type p53 activity did not desensitize CLL cells to jq1, which was also effective at inducing massive cell death in fludarabine resistant CLL cells, regardless of p53 status. Mice receiving jq1 exhibited a significant reduction in leukemic burden and prolonged survival compared to control mice, with a more pronounced effect observed in mice with mutant p53. These data demonstrate the potent effect of BET inhibition in B-CLL and more importantly, provide evidence as an effective treatment for aggressive forms of B-CLL with 17p deletion or TP53 mutation or chemoresistant refractory disease. Disclosures: Primo: Vivia Biotech: Employment. Rojas:Vivia Biotech: Employment. Martinez:Vivia Biotech: Employment. Bradner:Tensha Therapeutics: Dr. Bradner is a scientific founder of Tensha Therapeutics, which is developing drug-like derivatives of the JQ1 bromodomain inhibitor as cancer therapeutics, through a license from the Dana-Farber Cancer Institute. Other. Ballesteros:Vivia Biotech: Employment.
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Fukano, Ryo, i Masato Ishikawa. "Human-Error Prevention for Autonomous Edge Software Using Minimalistic Modern C++". Big Data and Cognitive Computing 3, nr 4 (4.11.2019): 52. http://dx.doi.org/10.3390/bdcc3040052.
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In science and engineering using edge-embedded software, it is necessary to demonstrate the validity of results; therefore, the software responsible for operating an edge system is required to guarantee its own validity. The aim of this study is to guarantee the validity of the sampled-time filter and time domain as fundamental elements of autonomous edge software. This requires the update law of a sampled-time filter to be invoked once per every control cycle, which we guaranteed by using the proposed domain specific language implemented by a metaprogramming design pattern in modern C++ (C++11 and later). The time-domain elements were extracted from the software, after which they were able to be injected into the extracted software independent from the execution environment of the software. The proposed approach was shown to be superior to conventional approaches that only rely on the attention of programmers to detect design defects. This shows that it is possible to guarantee the validity of edge software by using only a general embedded programming language such as modern C++ without auxiliary verification and validation toolchains.
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Reulen, Hans-Juergen, Gabriele Poepperl, Claudia Goetz, Franz Joseph Gildehaus, Michael Schmidt, Klaus Tatsch, Torsten Pietsch, Theo Kraus i Walter Rachinger. "Long-term outcome of patients with WHO Grade III and IV gliomas treated by fractionated intracavitary radioimmunotherapy". Journal of Neurosurgery 123, nr 3 (wrzesień 2015): 760–70. http://dx.doi.org/10.3171/2014.12.jns142168.
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OBJECT The aim in this study was to present long-term results regarding overall survival (OS), adverse effects, and toxicity following fractionated intracavitary radioimmunotherapy (RIT) with iodine-131− or yttrium-90−labeled anti-tenascin monoclonal antibody (131I-mAB or 90Y-mAB) for the treatment of patients with malignant glioma. METHODS In 55 patients (15 patients with WHO Grade III anaplastic astrocytoma [AA] and 40 patients with WHO Grade IV glioblastoma multiforme [GBM]) following tumor resection and conventional radiotherapy, radioimmunoconjugate was introduced into the postoperative resection cavity. Patients received 5 cycles of 90Y-mAB (Group A, average dose 18 mCi/cycle), 5 cycles of 131I-mAB (Group B, average dose 30 mCi/cycle), or 3 cycles of 131I-mAB (Group C, 50, 40, and 30 mCi). RESULTS Median OS of patients with AA was 77.2 months (95% CI 30.8 to > 120). Five AA patients (33%) are currently alive, with a median observation time of 162.2 months. Median OS of all 40 patients with GBM was 18.9 months (95% CI 15.8–25.3), and median OS was 25.3 months (95% CI18–30) forthose patients treated with the 131I-mAB. Three GBM patients are currently alive. One-, 2-, and 3-year survival probabilities were 100%, 93.3%, and 66.7%, respectively, for AA patients and 82.5%, 42.5%, and 15.9%, respectively, for GBM patients. Restratification of GBM patients by recursive partitioning analysis (RPA) Classes III, IV, and V produced median OSs of 31.1, 18.9, and 14.5 months, respectively (p = 0.004), which was higher than expected. Multivariate analysis confirmed the role of RPA class, age, and treatment in predicting survival. No Grade 3 or 4 hematological, nephrologic, or hepatic toxic effects were observed; 4 patients developed Grade 3 neurological deficits. Radiological signs of radionecrosis were observed in 6 patients, who were all responding well to steroids. CONCLUSIONS Median OS of GBM and AA patients treated with 131I-mABs reached 25.3 and 77.2 months, respectively, thus markedly exceeding that of historical controls. Adverse events remained well controllable with the fractionated dosage regimen.
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Shahin, Suliman Y., Tahani H. Abu Showmi, Sadeem H. Alzaghran, Hoda Albaqawi, Latifah Alrashoudi i Mohammed M. Gad. "Bond Strength of Orthodontic Brackets to Temporary Crowns: In Vitro Effects of Surface Treatment". International Journal of Dentistry 2021 (29.06.2021): 1–7. http://dx.doi.org/10.1155/2021/9999933.
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Background. The number of patients seeking orthodontic treatment has been consistently increasing. During orthodontic treatment, it is recommended to place the provisional restoration and to delay the final restoration until completion of orthodontic treatment. Recurrent bracket debonding necessitates orthodontists to prepare the bonding area with special measures. Objective. This study aimed to evaluate the effect of different grit sizes of diamond burs and sandblasting surface treatment on the shear bond strength of orthodontic brackets to provisional crowns. Materials and Methods. A total of 75 discs were fabricated from a bisacrylic composite and divided into 5 groups (n = 15) according to surface treatment by black, blue, and green diamond burs and sandblasting in addition to a control group. Metal orthodontic brackets were bonded to discs in a standardized conventional manner. All specimens were subjected to thermocycling with 5000 cycles of alternating 5°C and 55°C waterbaths. The shear bond strength test was performed using a universal testing machine. A scanning electron microscope (SEM) was used to analyze the surface treatment effect and features of debonded surfaces. The amount of composite resin left on the specimen surfaces was analyzed and classified with the adhesive remnant index. One-way ANOVA was performed at α = 0.05. Results. The shear bond strength of specimens treated with sandblasting was significantly higher than that of the control group under thermal aging conditions ( p = 0.022 ), as well as blue burs ( p = 0.001 ), while no significant differences were found between different grit diamond burs and the controls ( p > 0.05 ). Conclusion. Under thermocycling conditions, sandblasting of provisional crowns increases the bond strength of orthodontic brackets.
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Wei, V., M. Elektorowicz i J. A. Oleszkiewicz. "Electrically enhanced MBR system for total nutrient removal in remote northern applications". Water Science and Technology 65, nr 4 (1.02.2012): 737–42. http://dx.doi.org/10.2166/wst.2012.908.
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Thousands of sparsely populated communities scatter in the remote areas of northern Canada. It is economically preferable to adopt the decentralized systems to treat the domestic wastewater because of the vast human inhabitant distribution and cold climatic conditions. Electro-technologies such as electrofiltration, elctrofloatation, electrocoagulation and electrokinetic separation have been applied in water and conventional wastewater treatment for decades due to the minimum requirements of chemicals as well as ease of operation. The membrane bioreactor (MBR) is gaining popularity in recent years as an alternative water/wastewater treatment technology. However, few studies have been conducted to hyphenate these two technologies. The purpose of this work is to design a novel electrically enhanced membrane bioreactor (EMBR) as an alternative decentralized wastewater treatment system with improved nutrient removal and reduced membrane fouling. Two identical submerged membranes (GE ZW-1 hollow fiber module) were used for the experiment, with one as a control. The EMBR and control MBR were operated for 4 months at room temperature (20 ± 2 °C) with synthetic feed and 2 months at 10 °C with real sewage. The following results were observed: (1) the transmembrane pressure (TMP) increased significantly more slowly in the EMBR and the interval between the cleaning cycles of the EMBR increased at least twice; (2) the dissolved chemical oxygen demand (COD) or total organic carbon (TOC) in the EMBR biomass was reduced from 30 to 51%, correspondingly, concentrations of the extracellular polymeric substances (EPS), the major suspicious membrane foulants, decreased by 26–46% in the EMBR; (3) both control and EMBR removed >99% of ammonium-N and >95% of dissolved COD, in addition, ortho-P removal in the EMBR was >90%, compared with 47–61% of ortho-P removal in the MBR; and (4) the advantage of the EMBR over the conventional MBR in terms of membrane fouling retardation and phosphorus removal was further demonstrated at an operating temperature of 10 °C when fed with real sewage. The EMBR system has the potential for highly automated control and minimal maintenance, which is particularly suitable for remote northern applications.
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Zervou, Christina, Gerald Kugel, Cataldo Leone, Athanasios Zavras, Eileen Doherty i George White. "Enameloplasty effects on microleakage of pit and fissure sealants under load: an in vitro study". Journal of Clinical Pediatric Dentistry 24, nr 4 (1.07.2000): 279–85. http://dx.doi.org/10.17796/jcpd.24.4.e491n06064j85285.
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Enameloplasty has been implicated in the successful application of pit and fissure sealants. The present study aimed to evaluate the effect of enameloplasty technique on microleakage of sealants when occlusal force was applied on the teeth. The study also allowed a direct comparison of the effectiveness of enameloplasty, when two different burs were used. Six groups of ten human extracted wisdom teeth were tested. Group A: no load, conventional (no enameloplasty - control); Group B: no load, enameloplasty 1/2 round bur (Brasseler USA); Group C: no load, enameloplasty diamond fissure bur REF/UP 791( Ultradent); Group D: load 500 N, conventional , Group E: load 500 N, 1/2 round bur; Group F: load 500 N, diamond fissure bur. Specimens were thermocycled for 500 cycles at 5° and 55° with a dwell time of 30 seconds after load application. Microleakage was scored as distance of dye penetration with 0 = no microleakage and 3 = microleakage to underling fissure. The Kruskal-Wallis One Way Anova and Mann -Whitney U test showed group D having the greatest degree of microleakage statistically significant (p<0.05) comparing with other groups. Sealants prepared with the conventional technique (A, D) had statistically significant differences in microleakage with those prepared with enameloplasty (B,C,E, F) (p = 0.01). Enameloplasty in groups with no load (B, C) did reduce microleakage, but not significantly (p = 0.3) However, loaded teeth with enameloplasty appeared to perform superior, as compared to those without (p=0.005) Regarding the effect of load, teeth without load (Groups A,B, C) were found to have significantly less microleakage than teeth where mechanical force had been applied (Groups D, E, F), (p = 0.01). Microleakage in Group A (conventional technique without load) was significantly less than microleakage in Group D (conventional technique with load), (p = 0.04). However, load did not seem to influence microleakage when enameloplasty had been performed. This finding was true for both round bur enameloplasty (p = 0.29), and fissure bur enameloplasty (p = 0.26). There was no statistically significant difference between Groups B, E (round bur) and C, F (fissure bur) (p > 0.05), or between Groups B and C (p > 0.05) and between Groups E and F (p > 0.05). The results of the study indicated that enameloplasty reduced microleakage of pit and fissure sealants, especially when load was applied to teeth, irrespective of what bur was used to enlarge the fissure, as there was no statistical significant differences between the round and fissured diamond burs. The application of occlusal force to the tooth produces significantly more microleakage, unless enameloplasty is performed.
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Zhao, Bonan, Zhipeng Dong, Qiyan Wang, Yisong Xu, Nanxia Zhang, Weixing Liu, Fangning Lou i Yue Wang. "Highly Efficient Mesoporous Core-Shell Structured Ag@SiO2 Nanosphere as an Environmentally Friendly Catalyst for Hydrogenation of Nitrobenzene". Nanomaterials 10, nr 5 (3.05.2020): 883. http://dx.doi.org/10.3390/nano10050883.
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The size-uniformed mesoporous Ag@SiO2 nanospheres’ catalysts were prepared in one-pot step via reducing AgNO3 by different types of aldehyde, which could control the size of Ag@SiO2 NPs and exhibit excellent catalytic activity for the hydrogenation of nitrobenzene. The results showed that the Ag core size, monitored by different aldehydes with different reducing abilities, together with the ideal monodisperse core-shell mesoporous structure, was quite important to affect its superior catalytic performances. Moreover, the stability of Ag fixed in the core during reaction for 6 h under 2.0 MPa, 140 °C made this type of Ag@SiO2 catalyst separable and environmentally friendly compared with those conventional homogeneous catalysts and metal NPs catalysts. The best catalyst with smaller Ag cores was prepared by strong reducing agents such as CH2O. The conversion of nitrobenzene can reach 99.9%, the selectivity was 100% and the catalyst maintained its activity after several cycles, and thus, it is a useful novel candidate for the production of aniline.
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Qamhia, Issam I. A., Erol Tutumluer, Hasan Ozer, Heather Shoup, Sheila Beshears i James Trepanier. "Evaluation of Chemically Stabilized Quarry Byproduct Applications in Base and Subbase Layers through Accelerated Pavement Testing". Transportation Research Record: Journal of the Transportation Research Board 2673, nr 3 (21.02.2019): 259–70. http://dx.doi.org/10.1177/0361198118821099.
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Research conducted at the Illinois Center for Transportation evaluated sustainable applications of quarry byproducts (QB) or QB blended with coarse recycled aggregates in chemically stabilized base and subbase layers in flexible pavements. In total, eight full-scale test sections, including one conventional flexible pavement with no QB as the control section, were constructed over a subgrade with an engineered strength of 6% California bearing ratio. The test sections were stabilized with either 3% Type I Portland cement or 10% Class C fly ash by dry weight. Fractionated reclaimed asphalt pavements and fractionated recycled concrete aggregates were also used as the recycled coarse aggregates. Based on laboratory tests conducted to determine strength properties of the chemically stabilized samples, QB and recycled aggregates were blended in a ratio of 70% to30% by weight, respectively. A lightweight deflectometer was used to evaluate the quality of the construction and the curing of the test sections. The constructed test sections were then evaluated for performance through accelerated pavement testing (APT) and frequent measurement of surface deformations. The results of APT showed quite a satisfactory rutting performance of all the evaluated QB applications with no observed surface cracking after 135,000 cycles. Four of the test sections were also instrumented with soil pressure cells to measure the wheel load deviator stress on top of the subgrade. The pressure measurements indicated subgrade pressures 3−5 times lower for the stabilized QB sections compared with that of the conventional flexible pavement control section.
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Valverde, Victor, Yosuke Kondo, Yoshinori Otsuki, Torsten Krenz, Anastasios Melas, Ricardo Suarez-Bertoa i Barouch Giechaskiel. "Measurement of Gaseous Exhaust Emissions of Light-Duty Vehicles in Preparation for Euro 7: A Comparison of Portable and Laboratory Instrumentation". Energies 16, nr 6 (8.03.2023): 2561. http://dx.doi.org/10.3390/en16062561.
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The European Union’s ambition to reach climate neutrality and a toxic-free environment by 2050 entails, among other things, cleaner road vehicles. The European Commission’s proposal for the next regulatory emissions standard, Euro 7, requires the measurement of pollutants currently not regulated on the road. In this study we compared a prototype portable emissions measurement system (PEMS) measuring CO2, CO, NO, NO2, N2O, NH3, CH4, and HCHO based on infrared laser absorption modulation (IRLAM), and two Fourier transform infrared (FTIR) spectrometers with laboratory grade analyzers. To this end, one Euro 6d Diesel, one Euro 6d gasoline, and one Euro 4 gasoline vehicle were tested at −7 °C and 23 °C with various driving cycles covering traffic conditions to highway dynamic driving. The results demonstrated that the differences among the instruments were small: ±1 mg/km for HCHO, N2O, and CH4, ±2.5 mg/km for NH3, ±10–15 mg/km for NOx, ±50 mg/km or ±15% for CO (whichever was larger), and ±10–15 g/km for CO2. These values corresponded to <10–15% of the proposed Euro 7 limits or the emission levels of the tested vehicles. Our results confirm the feasibility of on-board systems to measure the conventional components including CO2 and the aforementioned additional pollutants.
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Lassila, Lippo V. J., Pekka K. Vallittu i Sufyan K. Garoushi. "Fatigue Strength of Fragmented Incisal Edges Restored with a Fiber Reinforced Restorative Material". Journal of Contemporary Dental Practice 8, nr 2 (2007): 9–16. http://dx.doi.org/10.5005/jcdp-8-2-9.
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Abstract Aim The aim of this study was to determine the compressive fatigue limits (CFLs) of fractured incisor teeth restored using either a conventional adhesive-composite technique or using fiber-reinforced composites (FRCs). Methods and Materials Fifteen extracted sound upper incisor teeth were prepared by cutting away the incisal one-third part of their crowns horizontally. The teeth were restored using three techniques. Group A (control group) was restored by reattaching the original incisal edge to the tooth. Group B was restored using particulate filler composite (PFC). Group C was restored with PFC and FRC by adding a thin layer of FRC to the palatal surface of the teeth. The bonding system used was a conventional etch system with primer and adhesive. All restored teeth were stored in water at room temperature for 24 h before they were loaded under a cyclic load with a maximum controlled regimen using a universal testing machine. The test employed a staircase approach with a maximum of 103 cycles or until failure occurred. Data were analyzed using analysis of variance (ANOVA) (p=0.05). Failure modes were visually examined. Results Group A (reattaching fractured incisal edge) revealed the lowest CFL values, whereas the creation of a new incisal edge with PFC revealed a 152% higher CFL value compared to Group A. Group C (teeth restored with FRC) revealed a 352% higher CFL than the control group. ANOVA revealed the restoration technique significantly affected the compressive fatigue limit (p<0.001). The failure mode in Group A and B was debonding of the restoration from the adhesive interface. While in Group C, the sample teeth fractured below their cemento-enamel junctions. Conclusion These results suggested an incisally fractured tooth restored with the combination of PFC and FRC-structure provided the highest CFL. Citation Garoushi SK, Lassila LVJ, Vallittu PK. Fatigue Strength of Fragmented Incisal Edges Restored with a Fiber Reinforced Restorative Material. J Contemp Dent Pract 2007 February;(8)2:009-016.
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Loredo, Antonio, Mauro Maya, Alejandro González, Antonio Cardenas, Emilio Gonzalez-Galvan i Davide Piovesan. "A Novel Velocity-Based Control in a Sensor Space for Parallel Manipulators". Sensors 22, nr 19 (27.09.2022): 7323. http://dx.doi.org/10.3390/s22197323.
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It is a challenging task to track objects moving along an unknown trajectory. Conventional model-based controllers require detailed knowledge of a robot’s kinematics and the target’s trajectory. Tracking precision heavily relies on kinematics to infer the trajectory. Control implementation in parallel robots is especially difficult due to their complex kinematics. Vision-based controllers are robust to uncertainties of a robot’s kinematic model since they can correct end-point trajectories as error estimates become available. Robustness is guaranteed by taking the vision sensor’s model into account when designing the control law. All camera space manipulation (CSM) models in the literature are position-based, where the mapping between the end effector position in the Cartesian space and sensor space is established. Such models are not appropriate for tracking moving targets because the relationship between the target and the end effector is a fixed point. The present work builds upon the literature by presenting a novel CSM velocity-based control that establishes a relationship between a movable trajectory and the end effector position. Its efficacy is shown on a Delta-type parallel robot. Three types of experiments were performed: (a) static tracking (average error of 1.09 mm); (b) constant speed linear trajectory tracking—speeds of 7, 9.5, and 12 cm/s—(tracking errors of 8.89, 11.76, and 18.65 mm, respectively); (c) freehand trajectory tracking (max tracking errors of 11.79 mm during motion and max static positioning errors of 1.44 mm once the object stopped). The resulting control cycle time was 48 ms. The results obtained show a reduction in the tracking errors for this robot with respect to previously published control strategies.
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NASCIMENTO, Armiliana Soares, Eliane Alves de LIMA, Márcia de Almeida DURÃO, Yasmine de Carvalho SOUSA, Tereza Cristina CORREIA i Rodivan BRAZ. "Marginal microleakage in Bulk Fill resins". Revista de Odontologia da UNESP 45, nr 6 (24.11.2016): 327–31. http://dx.doi.org/10.1590/1807-2577.08316.
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Abstract Introduction Despite advances and innovations in restorative dentistry, microleakage remains one of the main problems in this area. Objective To evaluate in vitro marginal microleakage of Bulk Fill resins in class II cavities, with cervical termination in the dentin. Material and method Cavities, standardized on the mesial and distal surfaces, were prepared in forty top molars and randomly assigned to four groups (n = 10), according to the resin used. G1 (control): Filtek Z350 (3M/ESPE); G2: Filtek Bulk Fill flow (3M/ESPE); G3: Surefill SDR (Dentsply); G4: X-tra (Voco). These were further subdivided into subgroups according to the strategy used to apply the adhesive (self-etch technique and conventional). After storage for 24 hours in an oven (37 °C), the samples were submitted to the thermocycling test (500 cycles: 5 °C/55 °C). They were later waterproofed, immersed in Basic Fuchsin (0.5%) and sectioned in the mesial-distal direction for evaluation using a stereo magnifying glass at 40X (Coleman) Scores from 0 to 3 were assigned according to the microinfiltration observed. The Mann-Whitney and Kruskal-Wallis tests, with a significance level of 5%, were used for statistical analysis. Result There was no statistically significant difference between the Bulk Fill resins when the total acid-etching technique was used. Only the Filtek Bulk fill flow resin presented statistically significant results when the application of the adhesive system strategy was considered, with worse results, in relation to other groups, when it the self-etching strategy was considered. Conclusion The degree of leakage of the bulk fill resins studied, in class II cavities, was not influenced by the method of application of the adhesive system (conventional or two-step self-etching bonding agent), except for the Filtek Bulk fill flow.
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Mergulhão, VA, LS de Mendonça, MS de Albuquerque i R. Braz. "Fracture Resistance of Endodontically Treated Maxillary Premolars Restored With Different Methods". Operative Dentistry 44, nr 1 (1.01.2019): E1—E11. http://dx.doi.org/10.2341/17-262-l.
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SUMMARY Purpose: The purpose of this in vitro study was to evaluate the resistance and patterns of fracture of endodontically treated maxillary premolars (ETPs) restored with different methods. Methods and Materials: Mesio-occluso-distal cavities were prepared in 50 extracted caries-free human maxillary premolars after endodontic treatment. The teeth were divided into five groups (n=10), according to the restorative method. G1: intact teeth (control group); G2: conventional composite resin; G3: conventional composite resin with a horizontal glass fiber post inserted between buccal and palatal walls; G4: bulk-fill flowable and bulk-fill restorative composites; and G5: ceramic inlay. For direct restorations, Filtek Z350 XT, Filtek Bulk Fill Flowable Restorative, and Filtek Bulk Fill Posterior Restorative were used. Indirect restorations were fabricated from a pressable lithium disilicate glass-ceramic (IPS e-max Press) and adhesively cemented (RelyX Ultimate). All specimens were subjected to thermocycling (5°C to 55°C/5000 cycles) and additionally submitted to cyclic loading 50,000 times in an Electro-Mechanical Fatigue Machine. Next, the specimens were subjected to a compressive load at a crosshead speed of 1 mm/min until fracture. The fractured specimens were analyzed to determine the fracture pattern using a stereomicroscope, and then representative specimens were carbon coated to allow for the studying of the fracture surface under scanning electron microscopy. One-way analysis of variance (ANOVA) was used to compare fracture resistance of the groups. The results of fracture patterns were submitted to the Fisher exact test (α=0.05). Results: All specimens survived fatigue. Mean (standard deviation) failure loads (N) for groups were as follows: G1: 949.6 (331.5); G2: 999.6 (352.5); G3: 934.5 (233.6); G4: 771.0 (147.4); and G5: 856.7 (237.5). The lowest fracture resistance was recorded for G4, and the highest ones were recorded for G2, followed by that of G1 and G3. One-way ANOVA did not reveal significant differences between groups (p>0.05). The highest repairable fracture rates were observed in G1 (100%) and G3 (80%). Conclusions: ETPs restored with conventional composite resin with or without horizontal fiber post, bulk-fill composite, and ceramic inlay showed fracture resistance similar to that of sound teeth. Conventional composite resin restorations exhibited the highest prevalence of unrepairable fractures, and the insertion of a horizontal fiber post decreased this prevalence. Intact teeth showed 100% of repairable fractures. It is difficult to extrapolate the results directly to a clinical situation due to the limitations of this study.
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Gallagher, Robert E., Esther L. Schachter Tokarz, Lawrence E. Morris, Tianna Dauses, Ivana Gojo, Marcel P. Devetten, Katarzyna Jamieson i in. "Effectiveness of Peripheral Blood (PB) Molecular Monitoring by Quantitative RT-PCR (Q-PCR) in Phase II Acute Promyelocytic Leukemia (APL) Trial J0422." Blood 112, nr 11 (16.11.2008): 1502. http://dx.doi.org/10.1182/blood.v112.11.1502.1502.
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Abstract Bone marrow (BM) is the accepted source for monitoring post-therapy minimal residual disease (MRD) in APL. PB is easier and less painful to obtain but variable, sometimes contradictory evidence has been presented for its efficacy in MRD monitoring. In this study, PB vs BM monitoring, as well as conventional, qualitative RT-PCR (C-PCR) vs Q-PCR were directly and prospectively compared for their effectiveness as part of an intensive MRD monitoring schedule applied as a safety measure to an investigative Phase II trial (J0422) designed to test the efficacy of minimizing chemotherapy exposure and treatment duration. This trial consisted of one cycle of induction with all-trans retinoic acid (ATRA) and daunorubicin, followed by consolidation with single-agent arsenic trioxide (ATO), followed by a maintenance phase of intermittent ATRA alone or with 6-mercaptopurine and methotrexate for patients (pts) with a presenting white blood cell count (WBC) of >10,000 WBC/uL. The MRD monitoring schedule was as follows: BM and PB after the induction and consolidation treatment modules (modules 1 & 2), then, PB every month and BM every 3 months during 2 years of maintenance therapy. C-PCR and Q-PCR were performed according to published procedures for monitoring the APL-specific fusion gene PML-RARα by the BIOMED-1 Concerted Action and the North American Cooperative Oncology Groups, respectively. Criteria for positive assays were: C-PCR, confirmed visualization of an appropriate-sized gel band after conventional, double-nested PCR amplification; Q-PCR, demonstration of a CT value <40 cycles by real-time PCR amplification in ≥2 of triplicate assays. Positive dilution controls to document detection with approximately 1 in 104 sensitivity were included in all experiments. Test samples were available from 26 patients with 3 to 38 months (mo) post-module-2 follow-up (median, 16 mo). After module-1 induction, 4 pts were positive by C-PCR (3 BM-only; 1 PB-only) and 9 pts were positive by Q-PCR (7 BM & PB, 2 PB-only). All 4 C-PCR and 4 Q-PCR positives occurred in pts with WBC <1,000 (6 pts), while 0 C-PCR and 2 Q-PCR positives occurred in pts with WBC >10,000 (7 pts), suggesting an association of pretreatment WBC with a difference in the initial dynamics of treatment response. After module-2 consolidation, 0 pts were positive by C-PCR and 3 by Q-PCR (1 BM & PB, 1 BM-only, 1 PB-only). During maintenance at the 3 mo shared BM/PB checkpoints, 0 C-PCR and 5/114 Q-PCR assays were positive (2 BM & PB, 1 BM-only, 2 PB-only), distributed among 3 pts. At monthly PB-only checkpoints, an additional 12/252 assays were positive by Q-PCR, none in a progressive pattern suggestive of impending molecular relapse. Overall, 1 – 3 Q-PCR assays were positive in 9 patients during the maintenance and follow-up periods. Among 8 pts who completed 24 mo maintenance, only 1/6 positive Q-PCR assays occurred at >12 mo, suggesting continued reduction of MRD during first 12 mo of maintenance therapy. No C-PCR assays were positive beyond module-1. In 1 exceptional pt, excluded from the above maintenance analysis, the Q-PCR assays became recurrently positive in BM and/or PB after 6 mo maintenance at a level below the criterion for molecular relapse (normalized quotient relative to the housekeeping gene GAPDH, NQGAPDH, ≥10−5). After 18 mo, the C-PCR became repeatedly positive in PB but not BM with Q-PCRs positive (2 BM & PB, 1 PB-only at shared checkpoints) in the NQGAPDH 4×10−7 to 4×10−6 range, which was associated with relapse in the central nervous system but not the BM. These results indicate that molecular monitoring of PB or BM was equally effective in detecting MRD and that Q-PCR was a more critical measure of MRD than C-PCR on protocol J0422 after single-cycle ATO-based consolidation therapy. The results further suggest that PB monitoring may be more effective in detecting extramedullary relapse, a relatively increasing cause of disease relapse with improved overall therapy for APL.
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Astone, Giuseppina, Luca Vincenzo Cappelli, William Chiu, Clarisse Kayembe, Rui Wang, Bin Yang, Kirti Sharma i in. "Selective STAT3 Degraders Dissect Peripheral T-Cell Lymphomas Vulnerabilities Empowering Personalized Regimens". Blood 138, Supplement 1 (5.11.2021): 865. http://dx.doi.org/10.1182/blood-2021-153995.
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Abstract Introduction: Peripheral T-cell lymphomas (PTCLs) include heterogeneous entities of rare and aggressive neoplasms. The improved understanding of the biological/molecular mechanisms driving T-cell transformation and tumor maintenance has powerfully propelled new therapeutic programs. However, despite this progress, PTCLs remain an unmet medical need. Recurrent aberrations and the deregulated activation of distinct signaling pathways have been mapped and linked to selective subtypes. The JAK/STAT signaling pathway's deregulated activation plays a pathogenetic role in PTCL, including ALCL subtypes. STATs regulate the differentiation/phenotype, survival and cell-growth, metabolism, and drug resistance of T-cell lymphomas as well as host immunosuppressive microenvironments. Although many drugs' discovery programs were launched, a plethora of compounds has failed. Methods: We have discovered heterobifunctional molecules by an iterative medicinal chemistry SAR campaign that potently and selectively degrade STAT3 in a proteasome-dependent manner. Conventional PTCL cell lines and Patient Derived Tumor Xenograft (PDTX) and/or derived cell lines (PDTX-CL), carrying either WT- or mutated-STAT3, were exposed to increasing amounts (50nM⇒5µM) of STAT3-degraders. Proteins and mRNA transcripts (2⇒144hrs) were assessed by deep-proteomics and paired-end RNA sequencing, combined with WB/flow cytometry and qRT-PCR. Cell-titer-glo, cell titer blue, Annexin-V and S-cell cycle analyses were used as readouts. Chromatin accessibility, STAT3 DNA binding, 3D chromosomal architecture reorganization and 5-hmC profiling were assessed by ATACseq, CHIPseq and Hi-C and H3K27ac Hi-CHIP and mass-spectrometry. Drug testing/discovery combinations (96-well-plate) were performed using a semi-automated flow-cytometry. A battery of PTCL PDTX models were tested in pre-clinical trials. Results: Treatment of ALK+ ALCL (SU-DHL1) led to the rapid (~6hrs.) and profound down-regulation of STAT3 followed by the loss of canonical STAT3-regulated proteins (SOCS3, MYC, Granzyme B, GAS1, and IL2RA), without appreciable changes for other STAT family members (STAT1, STAT5b). In vitro, cytoplasmic, nuclear, and mitochondrial STAT3 downregulation was maintained up to 144 hrs. Loss of STAT3 in ALK+/- ALCL and BIA-ALCL cells was associated with major transcriptional changes (7116-10615 and 15114 DEGs in ALK- and ALK+ ALCL, respectively), underscoring public/shared as well as private time-dependent signatures. Main down-regulated pathways included JAK-STAT, MAPK, NF-kB, PI3K, TGFb, and TNFa. Comparison of STAT3 shRNA (ALK+ ALCL) and STAT3 degrader (ALK-/ALK+ ALCL) signatures demonstrated a substantial and concordant gene modulation (24hrs) among all models with the highest overlaps between ALK+ ALCL (Figure 3). To identify direct STAT3 gene targets, we analyzed CHIPseq peaks and predicted bindings sites, demonstrating that canonical genes, i.e., SOCS3, Granzyme B, GAS1, IL2RA, STAT3, and CD30, were significantly downregulated. Conversely, CD58, CD274, and MCH-I/II were upregulated at late time points. By mapping the STAT3 binding sites in ALK+ and ALK- ALCL, we have identified 1077 and 2763 STAT3 peaks within promoter/5'-/3'- and distant intergenic regions, corresponding to both coding and non-coding genes. Therapeutically, in vitro treatments led to cell cycle arrest and profound growth inhibition, and over time increased cell death of PTCL cells, including ALCL. Accordingly, growth inhibition of ALCL xenograft and PDTX tumors was also achieved (Figure 2). To identify drugs that could synergize withSTAT3-degrader activity, we tested a compound library (40) targeting pro-tumorigenic PTCL pathways as well as FDA-approved compounds. Ongoing studies are in progress. Conclusion: We have discovered selective STAT3 degraders which control PTCL growth. STAT3 degraders are powerful tools to define the STAT3 pathogenetic mechanisms and dissect genes/pathways to be targeted for T-cell lymphoma eradication. These data provide additional rationale for testing STAT3 degraders in the clinic for the treatment of aggressive malignancies including PTCL/ALCL. Figure 1 Figure 1. Disclosures Yang: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Sharma: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Dey: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Karnik: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Elemento: Owkin: Consultancy, Other: Current equity holder; Volastra Therapeutics: Consultancy, Other: Current equity holder, Research Funding; Johnson and Johnson: Research Funding; Eli Lilly: Research Funding; Janssen: Research Funding; Champions Oncology: Consultancy; Freenome: Consultancy, Other: Current equity holder in a privately-held company; One Three Biotech: Consultancy, Other: Current equity holder; AstraZeneca: Research Funding. Horwitz: Affimed: Research Funding; Aileron: Research Funding; ADC Therapeutics, Affimed, Aileron, Celgene, Daiichi Sankyo, Forty Seven, Inc., Kyowa Hakko Kirin, Millennium /Takeda, Seattle Genetics, Trillium Therapeutics, and Verastem/SecuraBio.: Consultancy, Research Funding; Acrotech Biopharma, Affimed, ADC Therapeutics, Astex, Merck, Portola Pharma, C4 Therapeutics, Celgene, Janssen, Kura Oncology, Kyowa Hakko Kirin, Myeloid Therapeutics, ONO Pharmaceuticals, Seattle Genetics, Shoreline Biosciences, Inc, Takeda, Trillium Th: Consultancy; Celgene: Research Funding; C4 Therapeutics: Consultancy; Crispr Therapeutics: Research Funding; Daiichi Sankyo: Research Funding; Forty Seven, Inc.: Research Funding; Kura Oncology: Consultancy; Kyowa Hakko Kirin: Consultancy, Research Funding; Millennium/Takeda: Research Funding; Myeloid Therapeutics: Consultancy; ONO Pharmaceuticals: Consultancy; Seattle Genetics: Consultancy, Research Funding; Secura Bio: Consultancy; Shoreline Biosciences, Inc.: Consultancy; Takeda: Consultancy; Trillium Therapeutics: Consultancy, Research Funding; Tubulis: Consultancy; Verastem/Securabio: Research Funding. DeSavi: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company. Liu: Kymera Therapeutics: Current Employment, Current equity holder in publicly-traded company.
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Baungarten-Leon, Emilio Isaac, Gustavo Daniel Martín-del-Campo-Becerra, Susana Ortega-Cisneros, Maron Schlemon, Jorge Rivera i Andreas Reigber. "Towards On-Board SAR Processing with FPGA Accelerators and a PCIe Interface". Electronics 12, nr 12 (6.06.2023): 2558. http://dx.doi.org/10.3390/electronics12122558.
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This article addresses a novel methodology for the utilization of Field Programmable Gate Array (FPGA) accelerators in on-board Synthetic Aperture Radar (SAR) processing routines. The methodology consists of using High-Level Synthesis (HLS) to create Intellectual property (IP) blocks and using the Reusable Integration Framework for FPGA Accelerators (RIFFA) to develop a Peripheral Component Interconnect express (PCIe) interface between the Central Processing Unit (CPU) and the FPGA, attaining transfer rates up to 15.7 GB/s. HLS and RIFFA reduce development time (between fivefold and tenfold) by using high-level programming languages (e.g., C/C++); moreover, HLS provides optimizations like pipeline, cyclic partition, and unroll. The proposed schematic also has the advantage of being highly flexible and scalable since the IPs can be exchanged to perform different processing routines, and since RIFFA allows employing up to five FPGAs, multiple IPs can be implemented in each FPGA. Since Fast Fourier Transform (FFT) is one of the main functions in SAR processing, we present a FPGA accelerator in charge of the reordering stage of VEC-FFT (an optimized version of FFT) as a proof of concept. Results are retrieved in reversed bit order, and the conventional reordering function may consume more than half of the total clock cycles. Next, to demonstrate flexibility, an IP for matrix transposition is implemented, another computationally expensive process in SAR due to memory access.
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Noorollahian, Saeed, Zahra Zarei, Leila Sadeghalbanaei i Khashayar Pakzamir. "The Effect of Bonding Surface Design on Shear Bond Strength of 3D-Printed Orthodontic Attachments". International Journal of Dentistry 2023 (7.08.2023): 1–6. http://dx.doi.org/10.1155/2023/6697178.
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Introduction. This study compared the shear bond strength (SBS) of four innovative designs of the bonding surface of 3D-printed orthodontic attachments with conventional mesh design. Methods. In this in vitro study, the bonding surface design in different groups was as follows: Group 1, flat surface without any feature as a negative control; Group 2, concentric circles with no cuts; Group 3, concentric circles with 16 radial cuts; Group 4, concentric circles with 32 radial cuts; Group 5, small cones with a flat end and rounded edges; Group 6, mesh-based commercially available metal brackets of the maxillary central incisor (standard edgewise, Dentaurum®) as a positive control (n = 20). In Groups 1–5, attachments were designed with SolidWorks® Software and printed with a 2K DLP-LCD printer with hard tough resin (eSun®). All the samples were bonded to the restorative composite resin (Solafil®) surfaces with orthodontic composite resin (CuRAY-ECLIPSE®). The samples were examined for SBS with a universal testing machine after thermocycling (1,000 cycles of 5‒55°C). Data were analyzed with Shapiro–Wilk, one-way ANOVA, and Bonferroni tests. The statistical significance level was set at 0.05. Results. The mean SBS was significantly different between all the groups ( P < 0.001 ) except for Groups 2 and 5 ( P = 1.00 ) and Groups 2 and 6 ( P = 1.00 ). Group 4 had the highest mean of SBS. Conclusion. The bonding surface design significantly influenced the SBS of orthodontic attachments. The concentric circles with 32 cuts had higher bond strength than other designs and can be suggested as a new bonding surface design for orthodontic attachments.
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Manjum, Marjanul, Saheed Adewale Lateef, Hunter Addison McRay, William Earl Mustain i Golareh Jalilvand. "Low-Cost Processing of Highly Durable (>1000 cycles) Sulfur Cathodes for Li-S Batteries". ECS Meeting Abstracts MA2022-02, nr 6 (9.10.2022): 588. http://dx.doi.org/10.1149/ma2022-026588mtgabs.
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Lithium-sulfur (Li-S) batteries are one of the promising alternatives to modern Lithium-ion Battery (LIB) technology due to their superior specific energy density, which can satisfy the emerging needs of advanced energy storage applications such as electric vehicles and grid-scale energy storage and delivery. However, achieving this high specific energy density is hampered by several challenges inherent to the properties of sulfur and its discharge products. One major issue is related to the insulating nature of S and its fully discharged product (Li2S), which often leads to low utilization of the active material and poor rate capability. The poor electronic conductivity of these species can be overcome by utilizing conductive hosts, though they are dilutive and decrease the energy density, meaning that their mass ratio to the active material should be as low as possible [1]. Another crucial issue relates to the undesired solubility of certain sulfur discharge products, so-called long-chain Li polysulfides (LiPSs), in the conventional ether-based liquid electrolyte. The solubility of long-chain LiPSs promotes their free back-and-forth transport between the positive and negative electrodes, which results in poor cyclability and capacity decay [2, 3]. Despite the efforts to engineer and control the undesired LiPSs shuttling effect, advances have been mostly limited to a small number of cycles (100-200), or the need for complex and often expensive synthesis that has limited the rational development of new sulfur cathodes. At present, a large majority of the sulfur cathode research has focused on nano-architectured electrodes using 2D and 3D host materials for sulfur, such as carbon nanotubes, graphene, conductive scaffolds, yolk-shell structures, and the like, to increase the conductivity and alleviate the LiPSs shuttling [4]. Although these approaches have helped to increase the achievable capacity, and sometimes the cyclability, their synthesis methods have been highly complex, meaning that their manufacturing cost will be high. Also, in operating cells, it is highly unlikely that these complex structures can be effectively reproduced upon many charge-discharge cycles – meaning that capacity loss is essentially inevitable. Thus, developing novel, yet affordable and scalable, cathode architectures that can enhance the rapid transport of Li-ions to active sites for electrode reactions, accommodate discharge-induced volume expansion, and minimize the shuttling mechanism by sulfur encapsulation are still in great need. In this work, we present a low-cost and scalable processing method for highly durable sulfur cathodes containing commercial sulfur, carbon black, and polyvinylidene fluoride (PVDF). The sulfur cathode slurry was prepared through a simple and scalable recipe where the degree of binder dissolution into the solvent was controlled before electrode deposition. Variables such as the solvent:binder ratio, dissolution time, and agitation will be discussed. The microstructure of the sulfur cathodes was characterized using scanning electron microscopy. Through controlled dissolution of binder, a porous, swollen network of binder was achieved that adhered the sulfur and carbon particles while providing a highly porous structure that can accommodate the sulfur volume expansion during discharge and impede dissolution of the discharge products into the electrolyte by physically trapping them. The cycling performance of the sulfur cathodes prepared through the present novel processing was tested at C/10 and compared with those prepared through the conventional production techniques. The sulfur cathodes prepared with this novel electrode processing offered impressive capacity retention of 80% after 1000 cycles suggesting a considerable improvement in the shuttling effect and active material preservation. These results are expected to help move the production and manufacturing of Li-S batteries forward. References -J. Lee, T.-H. Kang, H.-Y. Lee, J. S. Samdani, Y. Jung, C. Zhang, Z. Yu, G.-L. Xu, L. Cheng, S. Byun et al., Advanced Energy Materials, vol. 10, no. 22, p. 1903934, 2020. Yang, G. Zheng, and Y. Cui, Chemical Society Reviews, vol. 42, no. 7, pp. 3018–3032, 2013. She, Y. Sun, Q. Zhang, and Y. Cui., Chemical society reviews, vol. 45, no. 20, pp. 5605-5634, 2016. Zhou, D. L. Danilov, R.-A. Eichel, and P. H. L. Notten, Advanced Energy Materials, vol. 1, p. 2001304, 2020.
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Goekbuget, Nicola, Karl-Heinz Baur, Joachim Beck, Helmut Diedrich, Monika Lamprecht, Lothar Leimer, Thomas Lipp i in. "Dexamethasone Dose and Schedule Significantly Influences Remission Rate and Toxicity of Induction Therapy in Adult Acute Lymphoblastic Leukemia (ALL): Results of the GMALL Pilot Trial 06/99." Blood 106, nr 11 (16.11.2005): 1832. http://dx.doi.org/10.1182/blood.v106.11.1832.1832.
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Abstract In 1999 the German Multicenter Study Group for Adult ALL (GMALL) activated a pilot study (GMALL 06/99). One major aim was to develop a new, shortened and intensified induction regimen based on the following new principles compared to previous GMALL trials: 1) Dexamethasone (DEXA) instead of prednisone to improve antileukemic activity and prophylaxis of CNS relapse 2) prephase with cyclophosphamide (CYCLO) 3) G-CSF parallel to chemo 4) intensified daunorubicin with two 2day cycles (DNR) vs 4 wkly applications 5)1 dose PEG-L-Asparaginase (ASP) instead of 14 d conventional ASP Induction I was followed by GMALL induction phase II as previously reported and a uniform consolidation I. Remission control took place on d24 and d44. Thereafter treatment was risk adapted. Induction I consisted of DEXA, CYCLO and G-CSF. In addition pts received PEG-ASP 1000 U/m2 (d13), vincristin 2 mg (d4,11,18) and DNR 45 mg/m2 (d4+5,11+12). The regimen was modified by 3 amendments which separated the study to 4 pilot phases. The major modifications referred to reduction of DEXA/CYCLO and earlier application of G-CSF. Table 1: Major modifications of induction phase I Drug Pilot 1 Pilot 2 Pilot 3 DEXA 40 mg/m2 (d1–3) 10 mg/m2 (d4–17) 10 mg/m2 (d 1–6,11–16) 10 mg/m2 (d 1–5,11–14) CYCLO 200 mg/m2 (d1–3) none none G-CSF from d13 from d4 from d4 Overall 843 pts were included between 4/99 and 10/03. The median age was 36 (15–65) yrs. Subtypes distribution was c-/pre B 65%, pro B 8%, early T 8%, thymic 14%, mature T 6%. 23% had Ph/BCR-ABL+ ALL. The overall CR rate was 83%, with 12% failure/PR and 7% early death (ED). Significant differences were detected for the pilot phases (p=.0008). The high mortality in pilot I was mainly due to infections. With lower doses of DEXA the rate of ED (p=.0002) and severe infections decreased significantly whereas the failure rate increased slightly. The earlier application of G-CSF contributed to a significant decrease of grade III/IV granulocytopenias and probably also mucositis. Table 2: Results and major toxicities (grade III/IV) of induction therapy Pilot 1 Pilot 2 Pilot3 P Evaluable 103 100 605 CR 76% 83% 82% .0008 PR/Failure 9% 9% 14% ED 16% 8% 5% Survival (3y) 45% 47% 47% >.05 Granulopenia 84% 72% 69% .008 Median duration 17d 15d 12d <.0001 Infections 30% 33% 14% <.0001 Mucositis 23% 14% 6% <.0001 We conclude that dose and schedule of DEXA in induction of ALL has a significant effect on rate of infections and ED. A dose reduced schedule with interruption to allow for early detection of infections led to a favourable CR rate of 82% with ED of 5% after only 6 wks of induction therapy. The parallel application of chemo and G-CSF rendered the regimen more feasible and contributed to the lower rate of infections and mucositis. The optimised regimen which includes again prephase with CYCLO is now used as induction therapy of the ongoing GMALL study 07/2003. Interim results confirmed the high antileukemic activity with CR rates of 89% and the feasibility with 4% ED. Beside the optimised induction the use of Imatinib in Ph+ ALL parallel to induction contributed to the improvement. Further progress is now attempted by additional use of rituximab in CD20 positive pts.
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Kamimae-Lanning, Ashley N., Tae H. Ha, Amy M. Skinner, Thomas B. Russell i Peter Kurre. "Developmental Programming of Bone Marrow Failure in a Murine Model of Fanconi Anemia". Blood 118, nr 21 (18.11.2011): 1334. http://dx.doi.org/10.1182/blood.v118.21.1334.1334.
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Abstract Abstract 1334 Bone marrow failure is the most common cause of morbidity and mortality from Fanconi anemia (FA), a recessively inherited disorder resulting from mutations in one of 15 known genes that cooperate in a DNA repair pathway. The underlying etiology is thought to reflect an accelerated postnatal exhaustion of the hematopoietic stem and progenitor cell (HSPC) pool. However, laboratory evidence of compromised hematopoietic function in patients generally precedes symptoms of cytopenia, and several other mesodermal-derived organ systems show defects with prenatal onset, including the skeletal system, heart, kidneys, and others. Further, recent experimental evidence in human embryonic stem cell lines suggested that RNA interference-mediated knock-down of FANCD2 and FANCA impairs development of hematopoietic cells. The fetal liver provides a unique microenvironment for development of definitive hematopoietic function and serves as a site of massive HSPC expansion. However, neither the potential developmental onset of bone marrow failure or non-stem cell-autonomous contributions in FA have been systematically clarified to-date. We relied on a murine model of FA with a transgenic disruption of Fancc to test the hypothesis that hematopoietic failure for this disease may have developmental origins. Although spontaneous bone marrow failure does not occur in this FA mouse model, animals recapitulate impaired repopulating ability, characteristic cell cycle abnormalities, and impaired cytokine responses. To determine whether number and function of fetal liver (FL) HSPCs affect postnatal hematopoietic function in FA mice, we plated unfractionated cells from 14.5 days post coitum (dpc) FL in methylcellulose and undertook a chronologic assessment of postnatal bone marrow progenitor clonogenicity. These studies showed that, compared with wild-type (wt) littermates, Fancc−/− animals demonstrate a progressive deficiency in progenitor number and function that increases with age, suggesting that HSPC attrition is developmentally programmed. Fancc−/−fetal mice revealed a 10% reduction in body mass and 33% lower total liver cell count compared with wt littermates. Cytogenetic analysis shows Fancc−/−FL cells exhibit mitomycin-c hypersensitivity characteristic of FA, with increased chromosomal breakage and radial formation. Livers of 14.5±.5 dpc Fancc−/−fetuses contain approximately 43% fewer c-Kit+Sca-1+ progenitor-enriched cells, compared with wt littermates. Cell cycle status of fetal livers revealed a characteristically increased proportion of Fancc−/− fetal liver progenitor-enriched (c-Kit+ Sca-1+) cells in G2-M phase of cell cycle, compared to wt littermate liver. When plated in methylcellulose assays, Fancc−/−FL showed an approximately 20% reduction in progenitor frequency, compared to wt littermates, and plating in mitomycin-c resulted in outgrowth of fewer colonies. Further, studies to determine the relative in vivo repopulating cell frequency were performed using CD45-isotype mismatched, submyeloablatively irradiated (750 cGy) animals. Recipients receiving unfractionated 14.5±.5 dpc Fancc−/−liver cells showed a slight, but consistent reduction in peripheral blood chimerism at serial timepoints (1–5 months) and bone marrow chimerism at sacrifice. We also found a 21% reduction in total Fancc−/−clonogenic bone marrow progenitor frequency by methylcellulose assay in primary recipients, compared to wt-transplanted controls. In sum, these studies suggest a developmental origin of hematopoietic failure in FA, whereby the prenatal onset potentially contributes to disease progression. Results contrast with a conventional model of postnatal stem cell attrition and may impact the development of preemptive therapies for FA patients. Disclosures: No relevant conflicts of interest to declare.
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Bhat, Ajaz A., H. Mang, Rajkumar S., T. M. Kotresh i U. K. Singh. "On-Board Oxygen Generation Using High Performance Molecular Sieve". Defence Life Science Journal 2, nr 4 (10.11.2017): 380. http://dx.doi.org/10.14429/dlsj.2.12274.
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<p class="p1">The majority of high performance combat aircrafts presently being operated by Indian air Force are fitted with conventional oxygen systems in which a replenishable store of oxygen is carried, most often as liquid oxygen and the flow of gas to each crew member is controlled by an individual pressure demand regulator in which the oxygen is diluted with cabin air to provide breathing gas.Moreover, in-flight refueling capability of present generation fighter aircraft has made it possible to fly for long durations (6 to 8 hours). In such case, the oxygen source becomes one of the limiting factors. In order to meet this requirement, a large supply of Gaseous Oxygen (GASOX) or Liquid Oxygen (LOX) have proven to be a costly affair and the Onboard Oxygen Generating System (OBOGS) has become a very convenient and attractive proposal. The OBOGS employs molecular sieves to adsorb nitrogen from engine bleed air using pressure swing adsorption (PSA) technique, wherein two molecular sieve beds are continuously cycled between steps of pressurization (adsorption) and depressurization (desorption) to generate oxygen enriched breathing gas for aircrew. This paper describes the design of OBOGS using high performance Lithium based Low Silica X-type (Li-LSX) molecular sieves and its performance characteristics. It consists of two Zeolite beds filled with Li-LSX material which adsorbs nitrogen fromengine bleed air tapped from Environmental Control System pipe line. The two beds are cycled by a 5/2 way solenoid valve. The input air is supplied to the solenoid valve through a coalescent filter to reduce moisture from it and a pressure regulator is fitted at the upstream of solenoid valve to regulate the system pressure. The experimental setup for evaluation of OBOGS is also discussed. The OBOGS, presented in this paper, meets all the performance requirements as specified in MIL-C-85521 (AS).<span class="Apple-converted-space"> </span></p>
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Havlicek, V., A. Gad, S. Papp, K. Stein, F. Palm, D. Tesfaye, M. Hoelker i U. Besenfelder. "232 EFFECT OF SUPEROVULATION PRETREATMENT ON DEVELOPMENTAL CHARACTERISTICS OF IN VITRO-FERTILIZED BOVINE EMBRYOS TRANSFERRED TO THE OVIDUCT-UTERUS ENVIRONMENT". Reproduction, Fertility and Development 28, nr 2 (2016): 247. http://dx.doi.org/10.1071/rdv28n2ab232.
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Superovulation is a routine procedure to stimulate growth and ovulation of multiple follicles. However, the hormonal changes in the reproductive tract after superovulation treatment affect the environment and subsequently the early embryo development. The aim of the study was to examine the effect of superovulation pretreatment on embryo development and gene expression of IVM/IVF derived embryos subsequently cultured in vivo. The cumulus‐oocyte complexes derived from slaughterhouse ovaries were in vitro matured and fertilized. The denuded presumptive zygotes were cultured in CR1 medium with 5% oestrous cow serum. A total of 788 cleaved embryos at Day 2 were transferred by transvaginal endoscopy into the oviduct of synchronized and superovulated heifers (superstimulated group, SS) and 784 cleaved embryos were transferred into the ipsilateral oviduct of single ovulated synchronized heifers (single ovulation group, SO). In total, 10 Simmental heifers were used for in vivo culture in a crossover design. The in vivo culture was repeated once at an interval of at least 6 weeks in the same animal. At Day 7, embryos were recovered by combined flushing of the oviducts by endoscopy and the adjacent part of the uterine horns by conventional procedure. The numbers of recovered blastocysts were recorded and the embryos were cultured for the following 48 h to determine the blastocyst rate at Days 8 and 9. Simultaneously, 410 cleaved embryos were cultured in vitro for 9 days (control group, C). Triplicate pools of 10 blastocysts recovered at Day 7 from each treatment group were used for RNA isolation. Real-time PCR using sequence specific primers was performed in StepOnePlus™ real time PCR system (Applied Biosystem, Foster City, CA, USA). A comparative threshold cycle method was used to quantify expression levels of the candidate genes compared to the internal control GAPDH gene. The number of recovered embryos after in vivo culture was significantly lower in the SS group compared with the SO group (66.9 v. 79.5%, respectively; P < 0.05). The blastocyst rates at Days 7, 8, and 9 in the SS, SO, and C groups were not significantly different (31.9, 43.3, and 47.1% v. 35.2, 48.5, and 53.5% v. 37.8, 50, and 56.1%, respectively). Molecular analysis of selected genes playing important roles during pre-implantation development revealed significantly lower expression levels of IL6, IL18, and ABCC2 between both experimental in vivo culture groups and the C-group. The IL18 was also significantly down-regulated in the SS-group compared to the SO-group. The transcription factor NFκB was found to be down-regulated in the SS-group compared to the SO and C groups (P < 0.05). In conclusion, we showed that the superovulation pretreatment did not affect blastocyst yield during the culture period but seemed to influence the expression of developmentally important genes in the resulting embryos.
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Gad, Mohammed M., Saleh Z. Alshehri, Shahad A. Alhamid, Alanoud Albarrak, Soban Q. Khan, Faris A. Alshahrani i Firas K. Alqarawi. "Water Sorption, Solubility, and Translucency of 3D-Printed Denture Base Resins". Dentistry Journal 10, nr 3 (9.03.2022): 42. http://dx.doi.org/10.3390/dj10030042.
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This study aimed to evaluate the water sorption, solubility, and translucency of 3D-printed denture base resins (NextDent, FormLabs, and Asiga), compare them to heat-polymerized acrylic denture base resins, and assess their performance under the effects of thermal cycling. A total of 80 acrylic disc specimens were used in the current study, categorized into four groups (n = 10); in one group, the samples were fabricated conventionally with a heat-polymerizing process (control), while the other three groups were fabricated digitally from different 3D-printed reins (NextDent, FormLabs, and Asiga). Specimens were fabricated according to the manufacturers’ recommendations and immersed in distilled water for 48 h at 37 °C. Data on water sorption, solubility, and translucency measurements (T1) were obtained. All the specimens were subjected to 5000 thermal cycles, and then the measures were repeated using the same method (T2). Data analysis was attained via ANOVA and the post hoc Tukey test (α = 0.05). The type of resin significantly affected the values of water sorption, solubility, and translucency (p < 0.001). The water sorption of 3D-printed resins was increased significantly in comparison to control with or without a thermal cycling effect. In terms of solubility, a significant increase in 3D-printed resins before thermocycling was observed; however, after thermocycling, Asiga had a significantly low value compared to the other groups (p < 0.001). Thermal cycling increased the water sorption and solubility of all tested materials. In comparison to control, the translucency of the 3D-printed resins was significantly decreased (p < 0.001). The translucency was significantly decreased per material in terms of the thermal cycling effect (before and after). NextDent showed significantly low translucency values (p < 0.001) compared to the other groups. All 3D-printed resin groups had higher water sorption and solubility and lower translucency values in comparison to the heat-polymerized resin group. Regardless of resin types, thermal cycling adversely affected all tested properties.