Journal articles on the topic 'Load Modulated Array'

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1

Sivasubramanian, Gobi Mohan, and Murali Narayanamurthy. "Implementation of PWM AC chopper controller for capacitor run induction motor drive via bacterial foraging optimization algorithm." International Journal of Reconfigurable and Embedded Systems (IJRES) 9, no. 3 (November 1, 2020): 169. http://dx.doi.org/10.11591/ijres.v9.i3.pp169-177.

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<p>This paper focuses on design of closed-loop control for pulse width modulated AC chopper controlled capacitor run induction motor drive engaging enriched optimization algorithm based on foraging of bacteria. Capacitor run induction motor is a non-linear device and its parameter varies under different functional point of the system. A linearized increment model for PWM AC chopper is illustrated for a particular functional point of the drive. The conventional method does not provide acceptable performance under different load conditions. Bacteria foraging optimization technique categorizes accurate control parameters for the superlative dynamic response under unit step load variations. Field Programmable Gate Array is implemented practically for a particular functional point of the drive to exhibit accurate performance. Experimental and simulated results are obtained to authenticate the effectiveness of the optimized controller.</p><p> </p>
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Dibiase, Marco, and Luca De Marchi. "An Optimal Shaped Sensor Array Derivation." Micromachines 14, no. 6 (May 30, 2023): 1154. http://dx.doi.org/10.3390/mi14061154.

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In Structural Health Monitoring (SHM) applications, the Direction of Arrival (DoA) estimation of Guided Waves (GW) on sensor arrays is often used as a fundamental means to locate Acoustic Sources (AS) generated by damages growth or undesired impacts in thin-wall structures (e.g., plates or shells). In this paper, we consider the problem of designing the arrangement and shape of piezo-sensors in planar clusters in order to optimize the DoA estimation performance in noise-affected measurements. We assume that: (i) the wave propagation velocity is unknown, (ii) the DoA is estimated via the time delays of wavefronts between sensors, and (iii) the maximum value of the time delays is limited. The optimality criterion is derived basing on the Theory of Measurements. The sensor array design is so that the DoA variance is minimized in an average sense by exploiting the Calculus of Variations. In this way, considering a three-sensor cluster and a monitored angles sector of 90°, the optimal time delays–DoA relations are derived. A suitable re-shaping procedure is used to impose such relations and, at the same time, to induce the same spatial filtering effect between sensors so that the sensor acquired signals are equal except for a time-shift. In order to achieve the last aim, the sensors shape is realized by exploiting a technique called Error Diffusion, which is able to emulate piezo-load functions with continuously modulated values. In this way, the Shaped Sensors Optimal Cluster (SS-OC) is derived. A numerical assessment via Green’s functions simulations shows improved performance in DoA estimation by means of the SS-OC when compared to clusters realized with conventional piezo-disk transducers.
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3

He, Ren, and Junmin Li. "Optimized design and performance analysis of a magnetic-field modulated brushless dual-mechanical port motor with Halbach array permanent magnets." Advances in Mechanical Engineering 12, no. 9 (September 2020): 168781402095775. http://dx.doi.org/10.1177/1687814020957754.

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In order to develop an electrical continuously variable transmission (E-CVT) to replace mechanical power coupling equipment applied in series-parallel hybrid electric vehicle (HEV), this paper proposes a magnetic-field modulated brushless dual-mechanical port motor with Halbach array permanent magnets, which has a more compact structure. The operating characteristics are analyzed by the lever analogy. It is concluded that the motor can realize the speed and torque decoupling between the engine and the wheel, which meet multi-mode operation requirements for HEV. To realize the multi-objective design of torque output, torque ripple and usage amount of permanent magnets, an optimization scheme combined parameter sensitivity with response surface methodology is adopted. The trade-offs among the optimization objectives are considered, then the key structural parameters and its optimal values are efficiently determined. Based on a two-dimensional model, the electromagnetic performances are simulated and analyzed. The results show that, after the parameters optimization, the no-load back electromotive force (EMF) has better sinusoidal characteristic, and the torque ripples and cogging torque peaks of the motor have been significantly reduced. Furthermore, a prototype motor is tested. The experimental results are consistent with the simulation results, which demonstrates the validity of the proposed structure and parameter optimization method.
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Ishaq, Muhammad, Yanbo Che, and Kifayat Ullah. "Switching Regulation in the Control of 5-Phase Permanent Magnet Synchronous Motor Fed by 3×5 Direct Matrix Converter." European Journal of Electrical Engineering 23, no. 1 (February 28, 2021): 27–35. http://dx.doi.org/10.18280/ejee.230104.

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Matrix converter is an AC-AC direct power converter comprising of an array of bi-directional switches. It does not require an intermediate DC-link and allows sinusoidal output waveforms with varying amplitudes and frequencies. The configuration of these bi-directional switches decides the number of inputs and outputs of the matrix converter. This research uses a direct matrix converter (DMC) as a phase-changing device that can convert a three-phase AC voltage into a 5-phase AC voltage. The DMC is modulated with the model predictive control algorithm. The output of DMC is fed to a five-phase permanent magnet synchronous motor (PMSM). The model predictive current control technique for DMC is carried out by developing a mathematical model of an input filter and PM motor used as a load. The predictive control of DMC results in sinusoidal output current, and it also enables the frequency variation in the output current. This frequency variation is useful in controlling the speed of the motor connected to the load. After controlling the 5-phase motor, the switching frequency regulation is done to observe its effect on the motor's stator current waveforms. Switching frequency regulation helps to limit the unnecessary switching of DMC. We developed a MATLAB-based Simulink model to study PMSM, and detailed results are presented. The results show that switching regulation can significantly reduce the switching frequency without compromising the current waveform quality.
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5

Sedaghat, Mohammad A., Vlasis I. Barousis, Ralf R. Müller, and Constantinos B. Papadias. "Load modulated arrays: a low-complexity antenna." IEEE Communications Magazine 54, no. 3 (March 2016): 46–52. http://dx.doi.org/10.1109/mcom.2016.7432147.

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6

Morgan, Helen M., Christoph Klein, Stephan G. Boehm, Kimron L. Shapiro, and David E. J. Linden. "Working Memory Load for Faces Modulates P300, N170, and N250r." Journal of Cognitive Neuroscience 20, no. 6 (June 2008): 989–1002. http://dx.doi.org/10.1162/jocn.2008.20072.

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We used event-related potential (ERP) methodology to examine neural activity associated with visual working memory (WM) for faces. There were two main goals. First, to extend previous findings of P300 load modulation to WM for faces. Second, to examine whether N170 and N250r are also influenced by WM load. Between one and four unfamiliar faces were simultaneously presented for memory encoding. After a 1-sec delay, a target face appeared, and participants had to judge whether this face was part of the previous face array. P300 amplitude decreased as WM load increased, and this P300 suppression was observed at both encoding and retrieval. WM load was also found to modulate other ERPs. The amplitude of the N170 elicited by the target face decreased with load, and this N170 decrease leveled off at load 2, reflecting the behavioral WM capacity of around two faces. In addition, the N250r, observed as an ERP difference for target faces that were present in the encoding array relative to target faces that were absent, was also reduced for higher WM loads. These findings extend previous work by showing that P300 modulation by WM load also occurs for faces. Furthermore, we show, for the first time, that WM load affects the N250r and the early visual N170 component. This suggests that higher visual areas play an important role in WM for faces.
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7

Bhat, Sandeep, and Ananthanarayanan Chockalingam. "Precoding for Multiuser Load-Modulated Arrays on the Downlink." IEEE Communications Letters 22, no. 9 (September 2018): 1774–77. http://dx.doi.org/10.1109/lcomm.2018.2849079.

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8

Bhat, Sandeep, and A. Chockalingam. "LSE Precoder for Load Modulated Arrays With Channel Modulation." IEEE Wireless Communications Letters 9, no. 8 (August 2020): 1295–99. http://dx.doi.org/10.1109/lwc.2020.2989134.

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9

Ullmann, Amy, Marc Dolan, Erol Fikrig, Joseph Piesman, and Nordin Zeidner. "Immunization with Adenoviral-expressed salivary gland proteins (SALPs) decreases spirochete load in a murine model of Lyme borreliosis (52.2)." Journal of Immunology 184, no. 1_Supplement (April 1, 2010): 52.2. http://dx.doi.org/10.4049/jimmunol.184.supp.52.2.

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Abstract It is known that tick saliva contains a vast array of proteins that function as anti-haemostatic, anti-inflammatory, and immunomodulatory factors when delivered to the vertebrate host. Previous studies have also demonstrated that prior exposure to tick saliva induced specific immunity to tick infestation, as well as affording protection against tick-transmitted Borrelia burgdorferi infection in the mammalian host. In our current studies we explored a vaccination technique to modulate tick feeding, using an adenovirus (Ad) expression system to deliver four salivary proteins (previously shown to modulate host immunity) derived from Ixodes scapularis; Salp15, Salp25A, Salp25D, and ISAC. C3H/HeJ mice were immunized individually with Ad-Salp15 and Ad-ISAC constructs, as well as all four constructs simultaneously. Immunized mice were then challenged with B. burgdorferi-infected I. scapularis ticks. Utilizing quantitative PCR, spirochete burden in target organs like heart and bladder was reduced by 55% compared to animals immunized with an empty Ad-cassette. The generation of anti-salivary protein antibodies in a murine model was also confirmed. Our results indicate that adenovirus expressed tick salivary proteins can stimulate dendritic cell expression of tick salivary proteins, as well as tick-specific humoral and cellular immune responses in mice, affording at least partial protection against subsequent tick-transmitted B. burgdorferi infection.
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Verma, Rakesh, Kartik Sehgal, Lin Zhang, Mehmet H. Kocoglu, Kavita Dhodapkar, and Madhav V. Dhodapkar. "Enrichment Of Embryonal Stem Cell Signature and Persistent Genomic Complexity In Residual Disease Following Pomalidomide Therapy In Myeloma." Blood 122, no. 21 (November 15, 2013): 4200. http://dx.doi.org/10.1182/blood.v122.21.4200.4200.

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Abstract Current therapy of myeloma including combination with IMID(R) immunomodulatory agent such as pomalidomide (POM) leads to high rates of clinical responses in patients with advanced multiple myeloma without translating to cures. Therefore, there is a need to better characterize the nature of residual disease after anti-myeloma therapy. POM has shown clinically promising efficacy in relapsed myeloma but nearly all patients eventually progress. In order to better understand the nature of residual disease, we compared baseline CD138+ myeloma tumor cells from 3 patients with those remaining after completing 2 cycles of therapy with POM (2-4 mg/day) and dexamethasone (40 mg/week). CD138+ plasma cells were isolated from the bone marrow before and after POM therapy and analyzed with gene expression profiling (GEP), and whole exome sequencing (WES). Principal component analysis (PCA) on the GEP data (pre vs. post POM treatment) revealed that in contrast to baseline samples, the ones with residual disease were clustered together, and this was further confirmed with unsupervised hierarchical clustering. Analysis of differentially expressed genes revealed nearly 600 differentially modulated genes, including some involved in the immune system regulation, inflammatory pathways and stem cells. Gene set enrichment analysis (GSEA) identified enrichment of distinct gene-sets/pathways including- transcriptional targets regulated by core embryonal stem (ES) cell factors SOX2 and NANOG. Analysis of genes in the core ES signature (Nat Genet. 2008; 40: 499) revealed that nearly 80% of these ES genes were enriched in the residual disease after treatment with POM. Whole exome sequencing has emerged as a powerful tool to dissect the genomic complexity in cancer. Genomic DNA from bone marrow derived CD138+ tumor cells before and after POM therapy was captured on the NimbleGen 2.1M human exome array and subjected to 74 base paired-end reads on the Illumina HiSeq instrument as described previously (Proc Natl Acad Sci U S A. 2009; 106:19096). Sequence reads were mapped to the reference genome (hg19) using the ELAND program. Reads outside the targeted sequences were discarded and statistics on coverage were collected from the remaining reads using perl scripts. ELAND was also used for indel detection. For matched normal/germline and CD138+ tumor pairs, somatic mutations were called by comparing reference and non-reference reads from the matched pair by Fisher’s exact test with tumor-specific thresholds determined from approximation of the null distribution. WES analysis of baseline (pre therapy) samples identified a median of 36 protein altering coding mutations per sample. Importantly, the degree of mutational load was very comparable between baseline and residual disease (post therapy), and nearly 80% of the mutations detected in the residual disease were also observed at baseline. These data suggest that residual disease following therapy in myeloma is characterized by high level of genomic complexity similar to that observed at baseline. However in spite of the genetic heterogeneity and complexity at baseline, the residual CD138+ plasma cells converge to a distinct signature enriched in a transcriptional program associated with embryonal stem cell genes known to be targets of SOX2 and NANOG. Drug resistant/residual CD138+ tumor cells in myeloma therefore show transcriptional profiles previously implicated in cancer stem cells. Targeting stemness-associated genes may be essential to effectively treat residual disease in myeloma. Disclosures: No relevant conflicts of interest to declare.
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11

Adang, Laura A., Costin Tomescu, Wai K. Law, and Dean H. Kedes. "Intracellular Kaposi's Sarcoma-Associated Herpesvirus Load Determines Early Loss of Immune Synapse Components." Journal of Virology 81, no. 10 (February 28, 2007): 5079–90. http://dx.doi.org/10.1128/jvi.02738-06.

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ABSTRACT Lifelong infection is a hallmark of all herpesviruses, and their survival depends on countering host immune defenses. The human gammaherpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) encodes an array of proteins that contribute to immune evasion, including modulator of immune recognition 2 (MIR2), an E3 ubiquitin ligase. Exogenously expressed MIR2 downregulates the surface expression of several immune synapse proteins, including major histocompatibility complex (MHC) class 1, ICAM-1 (CD54), and PECAM (CD31). Although immunofluorescence assays detect this lytic gene in only 1 to 5% of cells within infected cultures, we have found that de novo infection of naive cells leads to the downregulation of these immune synapse components in a major proportion of the population. Investigating the possibility that low levels of MIR2 are responsible for this downregulation in the context of viral infection, we found that MIR2 transduction recapitulated the patterns of surface downregulation following de novo infection and that both MIR2 promoter activation, MIR2 expression level, and immune synapse component downregulation were proportional to the concentration of KSHV added to the culture. Additionally, MIR2-specific small interfering RNA reversed the downregulation effects. Finally, using a sensitive, high-throughput assay to detect levels of the virus in individual cells, we also observed that downregulation of MHC class I and ICAM-1 correlated with intracellular viral load. Together, these results suggest that the effects of MIR2 are gene dosage dependent and that low levels of this viral protein contribute to the widespread downregulation of immune-modulating cell surface proteins during the initial stages of KSHV infection.
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12

Drynda, Andreas, Susanne Drynda, Jörn Kekow, Christoph Lohmann, and Jessica Bertrand. "Differential Effect of Cobalt and Chromium Ions as Well as CoCr Particles on the Expression of Osteogenic Markers and Osteoblast Function." International Journal of Molecular Sciences 19, no. 10 (October 5, 2018): 3034. http://dx.doi.org/10.3390/ijms19103034.

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The balance of bone formation and resorption is the result of a regulated crosstalk between osteoblasts, osteoclasts, and osteocytes. Inflammation, mechanical load, and external stimuli modulate this system. Exposure of bone cells to metal ions or wear particles are thought to cause osteolysis via activation of osteoclasts and inhibition of osteoblast activity. Co2+ ions have been shown to impair osteoblast function and the expression of the three transforming growth factor (TGF)-β isoforms. The current study was performed to analyze how Co2+ and Cr3+ influence the expression, proliferation, and migration profile of osteoblast-like cells. The influence of Co2+, Cr3+, and CoCr particles on gene expression was analyzed using an osteogenesis PCR Array. The expression of different members of the TGF-β signaling cascade were down-regulated by Co2+, as well as several TGF-β regulated collagens, however, Cr3+ had no effect. CoCr particles partially affected similar genes as the Co2+treatment. Total collagen production of Co2+ treated osteoblasts was reduced, which can be explained by the reduced expression levels of various collagens. While proliferation of MG63 cells appears unaffected by Co2+, the migration capacity was impaired. Our data may improve the knowledge of changes in gene expression patterns, and the proliferation and migration effects caused by artificial materials.
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Sun, Liping, and Xiaozhi Liu. "Optoelectronic Hybrid Network Architecture and Its Performance Analysis." Journal of Nanoelectronics and Optoelectronics 15, no. 7 (July 1, 2020): 831–40. http://dx.doi.org/10.1166/jno.2020.2810.

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Optoelectrical hybrid network technology is introduced into a network based on pure electrical packet switching, which increases network capacity and reduces power consumption. However, the problems of long configuration time and complex management of optical circuit switches affect the performance of hybrid optoelectrical networks. A new type of hybrid optoelectronic network architecture (HOEP) cooperated by Ethernet packet switching network and optical wavelength routing network was designed in the study. The optical routing network transmitted and received optical signals by using a circular array waveguide grating router, and transmitted the optical signal carrying data to the target port based on the characteristics of wavelength cyclic routing. The entire process only needed to modulate the data signal, and did not need to configure the optical wavelength routing network. At the same time, in order to further improve the resource utilization of optical nodes, a kind of intelligent node dynamic reconstruction (RC) algorithm was designed. Combining with network link utilization, cache occupancy, and network load value, this method could dynamically adjust the usage distribution of optical nodes for reconstruction. During the experiment, the RC algorithm was applied to the HOEP network architecture. Compared with other typical network architectures, the HOEP network proposed in the study can effectively reduce the network cost, power consumption, and improve network throughput. Moreover, the introduction of RC algorithm and network equipment can make the cost remain within the controllable range, while it can further increase the network throughput and reduce the power consumption of the HOEP network, thereby meeting the dynamic demand for network bandwidth with larger data traffic.
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Sayenko, Dimitry G., Claudia Angeli, Susan J. Harkema, V. Reggie Edgerton, and Yury P. Gerasimenko. "Neuromodulation of evoked muscle potentials induced by epidural spinal-cord stimulation in paralyzed individuals." Journal of Neurophysiology 111, no. 5 (March 1, 2014): 1088–99. http://dx.doi.org/10.1152/jn.00489.2013.

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Epidural stimulation (ES) of the lumbosacral spinal cord has been used to facilitate standing and voluntary movement after clinically motor-complete spinal-cord injury. It seems of importance to examine how the epidurally evoked potentials are modulated in the spinal circuitry and projected to various motor pools. We hypothesized that chronically implanted electrode arrays over the lumbosacral spinal cord can be used to assess functionally spinal circuitry linked to specific motor pools. The purpose of this study was to investigate the functional and topographic organization of compound evoked potentials induced by the stimulation. Three individuals with complete motor paralysis of the lower limbs participated in the study. The evoked potentials to epidural spinal stimulation were investigated after surgery in a supine position and in one participant, during both supine and standing, with body weight load of 60%. The stimulation was delivered with intensity from 0.5 to 10 V at a frequency of 2 Hz. Recruitment curves of evoked potentials in knee and ankle muscles were collected at three localized and two wide-field stimulation configurations. Epidural electrical stimulation of rostral and caudal areas of lumbar spinal cord resulted in a selective topographical recruitment of proximal and distal leg muscles, as revealed by both magnitude and thresholds of the evoked potentials. ES activated both afferent and efferent pathways. The components of neural pathways that can mediate motor-evoked potentials were highly dependent on the stimulation parameters and sensory conditions, suggesting a weight-bearing-induced reorganization of the spinal circuitries.
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Lee, Kyung Hoon, Kunhao Yu, Hasan Al Ba’ba’a, An Xin, Zhangzhengrong Feng, and Qiming Wang. "Sharkskin-Inspired Magnetoactive Reconfigurable Acoustic Metamaterials." Research 2020 (February 5, 2020): 1–13. http://dx.doi.org/10.34133/2020/4825185.

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Most of the existing acoustic metamaterials rely on architected structures with fixed configurations, and thus, their properties cannot be modulated once the structures are fabricated. Emerging active acoustic metamaterials highlight a promising opportunity to on-demand switch property states; however, they typically require tethered loads, such as mechanical compression or pneumatic actuation. Using untethered physical stimuli to actively switch property states of acoustic metamaterials remains largely unexplored. Here, inspired by the sharkskin denticles, we present a class of active acoustic metamaterials whose configurations can be on-demand switched via untethered magnetic fields, thus enabling active switching of acoustic transmission, wave guiding, logic operation, and reciprocity. The key mechanism relies on magnetically deformable Mie resonator pillar (MRP) arrays that can be tuned between vertical and bent states corresponding to the acoustic forbidding and conducting, respectively. The MRPs are made of a magnetoactive elastomer and feature wavy air channels to enable an artificial Mie resonance within a designed frequency regime. The Mie resonance induces an acoustic bandgap, which is closed when pillars are selectively bent by a sufficiently large magnetic field. These magnetoactive MRPs are further harnessed to design stimuli-controlled reconfigurable acoustic switches, logic gates, and diodes. Capable of creating the first generation of untethered-stimuli-induced active acoustic metadevices, the present paradigm may find broad engineering applications, ranging from noise control and audio modulation to sonic camouflage.
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Lamba, Jatinder K., Stanley Pounds, Xueyuan Cao, Susana C. Raimondi, James R. Downing, Raul C. Ribeiro, and Jeffrey Rubnitz. "Methylation of DNMT3B Strongly Associates with the Methylome, Cytogenetic Risk Groups, and Prognosis of Pediatric Acute Myeloid Leukemia." Blood 126, no. 23 (December 3, 2015): 2434. http://dx.doi.org/10.1182/blood.v126.23.2434.2434.

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Abstract Objective: Epigenetic mechanisms such as DNA methylation are deregulated in cancer. Aberrant DNA methylation is reported to have clinical significance in acute myeloid leukemia (AML) in adults. In this study, we performed a detailed genome-wide screening of DNA methylation to identify the epigenetic signatures that are associated with gene expression and prognosis in pediatric patients with AML. Methods: Illumina 450K methylation microarray and Affymetrix U133A gene expression microarray profiles were obtained for 151 patients treated on the multicenter clinical trial AML02. For each gene, canonical correlation analysis (CCA) was performed to summarize its methylation and expression signals into 1 expression score and 1 methylation score. We then used the statistical tool called projection onto the most interesting statistical evidence (PROMISE) to test whether the CCA expression and methylation scores were associated with a clinically meaningful pattern of in vitro resistance (IVR) to cytarabine, the presence of detectable minimal residual disease (MRD) after the first course of chemotherapy, and event-free survival (EFS). In the PROMISE analysis, low IVR, less MRD, and better EFS were defined as a beneficial pattern and the converse was defined as a detrimental pattern for patients. To address multiplicity, we computed the false discovery rate (FDR) for the results obtained from statistical analysis. Results: The DNA methyltransferase gene DNMT3B, which has been implicated in adult AML, was one of thirteen genes with the smallest possible permutation p-value in both CCA and PROMISE analyses. DNMT3B showed very statistically significant methylation-expression correlation (CCA r = -0.74, P = 7 × 10-14, FDR = 9.7 × 10-12). Also, DNMT3B showed very compelling evidence of a clinically meaningful pattern of association with IVR, MRD, and EFS (Figure 1; PROMISE P < 0.00001, FDR < 0.001). In particular, a higher CCA-defined methylation score was associated with lower IVR (P = 0.14), less MRD (P < 0.0001), and better EFS (P = 0.00003). A higher CCA-defined expression score was associated with higher IVR (P = 0.11), greater MRD (P < 0.0001), and poorer EFS (P = 0.00024). Further, the methylation of DNMT3B was strongly associated with each of the cytogenetic risk groups defined at diagnosis (P = 9.7 × 10-13) and the genome-wide methylation load (CCA r = 0.80, P < 1 × 10-16). Conclusion: Taken together, these results suggest that methylation of the DNMT3B locus modulates DNMT3B expression, thereby disrupting epigenetic regulation, altering the methylome, and influencing disease progression in and clinical prognosis of pediatric patients with AML. Our results provide evidence that adding demethylating agents to standard chemotherapy might improve the prognosis of pediatric patients with AML. Additional clinical and basic research is needed to further elucidate the biological mechanisms involved in the epigenetic modifications occurring in AML and to determine the optimal strategy to incorporate demethylating agents into the treatment for AML. Figure 1. (A) Scatterplot of the CCA-defined methylation score and expression score summarizing the signals and correlation of 21 methylation array probe-sets and 1 expression array probe-set annotated to DNMT3B. Each point represents 1 patient. The colored barcode panels on the right and top margins of the figure represent bars at the values of the methylation score (right margin panels) and expression score (top margin panels) colored according to whether the patient experienced a pharmacologic or clinical endpoint (IVR, MRD, or EFS) that was statistically indicative of a good (blue bar) or poor (red bar) outcome. Low-, standard-, and high-risk cytogenetic subgroups are indicated by circles, triangles, and crosses, respectively. (B) EFS according to the CCA-defined methylation score for DNMT3B. (C) EFS according to the CCA-defined expression score for DNMT3B. Figure 1. (A) Scatterplot of the CCA-defined methylation score and expression score summarizing the signals and correlation of 21 methylation array probe-sets and 1 expression array probe-set annotated to DNMT3B. Each point represents 1 patient. The colored barcode panels on the right and top margins of the figure represent bars at the values of the methylation score (right margin panels) and expression score (top margin panels) colored according to whether the patient experienced a pharmacologic or clinical endpoint (IVR, MRD, or EFS) that was statistically indicative of a good (blue bar) or poor (red bar) outcome. Low-, standard-, and high-risk cytogenetic subgroups are indicated by circles, triangles, and crosses, respectively. (B) EFS according to the CCA-defined methylation score for DNMT3B. (C) EFS according to the CCA-defined expression score for DNMT3B. Disclosures No relevant conflicts of interest to declare.
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Xu, Yan, Matthew Ho, Mehmet Kemal Samur, Kenneth Wen, Shuhui Deng, Lanting Liu, Tengteng Yu, et al. "Ywhae/14-3-3ε Expression Promotes Translation Initiation and Protein Synthesis in Multiple Myeloma Regulating Proteasome Load and Contributing to Proteasome Inhibitor Sensitivity/Resistance." Blood 134, Supplement_1 (November 13, 2019): 5539. http://dx.doi.org/10.1182/blood-2019-130902.

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Dysregulated translational control and high protein turnover is a feature of multiple myeloma (MM) cells; as a result, proteasome inhibitors (PI), triggering a misfolded protein stress and death response, have been extremely successfully in MM therapy. But despite success of PIs and other novel therapeutic approaches, majority of patients progress; thus, investigating the mechanisms driving the drug sensitivity and/or resistance is important. We here report a novel chaperone protein 14-3-3ε with significant impact on MM cell pathobiology and patient outcome. 14-3-3 proteins are a family of master regulators of intracellular signaling that influence several cellular processes through binding to specific serine/threonine-phosphorylated residues on a diverse array of cellular proteins. With known interaction of 14-3-3 proteins with several functionally diverse molecules and well recognized chaperon function, we sought to evaluate their role in impacting proteasome activity. We compared the sensitivity of 14 MM cell lines to two proteasome inhibitors, Bortezomib (BTZ) and Carfilzomib (CFZ) with expression of all 14-3-3 proteins at both mRNA and protein levels. We compared the measured drug activity and individual 14-3-3 gene expression across all cell lines by Pearson correlation coefficients and observed that the expression level of only YWHAE (coding gene for the isoform 14-3-3ε) showed a significant negative correlation with both BTZ and CFZ response. We therefore evaluated its expression in primary MM cells and found its lower expression to be associated with poor outcome in MM patients receiving a bortezomib (Btz)-based therapy. To elucidate the underlying molecular mechanism responsible for 14-3-3ε contribution to PIs sensitivity, we performed integrated analysis of protein interactome and transcriptomic changes following 14-3-3ε gene modulation. These studies showed that 14-3-3ε impacts mTORC1 signaling in MM cells by binding to serine-phosphorylated residues on mTOR and its upstream negative regulator TSC2, resulting in mTORC1 activation. Conversely, depletion of 14-3-3ε inhibits TSC2 phosphorylation, causing a subsequent inhibition of mTORC1 signaling. One major conserved function of mTORC1 is to promote mRNA translation and therefore protein synthesis via activation of S6 kinase 1 (S6K1) as well as inhibition of the eukaryotic initiation factor 4E (eIF4E) binding protein (4E-BP). We have therefore assessed the impact of 14-3-3ε on translational efficiency in MM cells. In the viable MM cell population, 14-3-3ε depletion caused up to 50% reduction of protein synthesis in three MM cell lines, whereas 14-3-3ε overexpression in the KMS20 cell line or addback in YWHAE-KO cells (H929 and KMS11) resulted in a marked upregulation of protein synthesis. As MM is characterized by excess production of monoclonal immunoglobulins, we evaluated impact of 14-3-3ε perturbation on intracellular and secretion light chains production. We observed a significant decrease in the intracellular abundance and secretion of the light chains with 14-3-3ε KD in all MM cell lines tested. These observations were corroborated by gain-of-function studies where ectopic overexpression of 14-3-3ε in MM cells was associated with increased protein load (and an enhanced sensitivity to PIs) in vitro as well as in vivo. Importantly, we confirmed a significant correlation between 14-3-3ε expression, PIs sensitivity and protein load (evaluated as M protein production) in primary MM cells from two independent datasets. Moreover, MM patients with del17p, where 14-3-3ε is located, have lower 14-3-3ε expression and decreased monoclonal protein level, providing an explanation for inability of BTZ to overcome high-risk feature associated with del17p. In conclusion, we here report for the first time a unique function for 14-3-3ε in modulating the sensitivity to PIs through regulation of protein synthesis and M protein load in MM cells. Altogether these observations suggest that 14-3-3ε is a predictor of clinical outcome and may serve as a potential target to modulate PIs sensitivity in MM. Disclosures Anderson: Sanofi-Aventis: Other: Advisory Board; OncoPep: Other: Scientific founder ; C4 Therapeutics: Other: Scientific founder ; Janssen: Other: Advisory Board; Gilead Sciences: Other: Advisory Board. Munshi:Takeda: Consultancy; Takeda: Consultancy; Oncopep: Consultancy; Abbvie: Consultancy; Abbvie: Consultancy; Adaptive: Consultancy; Amgen: Consultancy; Amgen: Consultancy; Celgene: Consultancy; Oncopep: Consultancy; Adaptive: Consultancy; Janssen: Consultancy; Celgene: Consultancy; Janssen: Consultancy.
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Zhang, Xing-Ding, Veerabhadran Baladandayuthapani, Heather Yan Lin, Bart Barlogie, Saad Z. Usmani, Lin Yang, and Robert Z. Orlowski. "Identification Of Tight Junction Protein (TJP)-1 As a Modulator and Biomarker Of Proteasome Inhibitor Sensitivity In Multiple Myeloma." Blood 122, no. 21 (November 15, 2013): 123. http://dx.doi.org/10.1182/blood.v122.21.123.123.

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Abstract Background Inhibition of the ubiquitin-proteasome pathway through the use of proteasome inhibitors (PIs) has been validated by our group and others as a successful strategy against multiple myeloma that has improved patient outcomes. However, these agents are currently used without patient selection, as no biomarkers have been validated that identify patients most or least likely to benefit. Also, drug resistance emerges in the vast majority through largely undefined mechanisms, and limits the activity of further therapy based on PIs. There is therefore an urgent need to identify such biomarkers, especially if they could also represent novel therapeutic targets to achieve resensitization. Methods We compared gene expression profiles (GEPs) of a panel of bortezomib-resistant myeloma cell lines and their vehicle-treated, drug-naïve counterparts to identify significant changes associated with drug resistance. In addition, using the Lentiviral GeneNet™ small hairpin (sh) RNA Library, we performed genome-wide RNA interference (RNAi) to identify genes whose knockdown conferred resistance. Genes of interest were subjected to further validation using myeloma cell lines,primary samples, murine models, and using clinically annotated GEP databases. These studies were supported by the M. D. Anderson Cancer Center SPORE in Multiple Myeloma. Results Bortezomib resistance was associated with decreased expression of TJP1 by GEP studies of isogenic bortezomib-resistant and -sensitive cell lines. TJP1 was also identified as a chemoresistance factor by RNA interference designed to detect genes that conferred a survival advantage after drug treatment. Suppression of TJP1 using shRNAs in RPMI 8226 and U266 myeloma cell lines with high TJP1 expression reduced sensitivity to both bortezomib and carfilzomib. Conversely, its over-expression in MOLP-8 cells, which had low TJP1 levels, conferred enhanced sensitivity to both PIs. Also, forced expression of TJP1 in bortezomib-resistant RPMI 8226 cells that had lost endogenous TJP1 levels restored drug sensitivity. In these resistant cells, TJP1 promoter hypermethylation was found, and treatment with decitabine restored both TJP1 expression, and sensitivity to bortezomib or carfilzomib. GEP studies showed TJP1 suppression was associated with enhanced expression of MHC class II region genes, including PSMB8 and PSMB9. This was mirrored at the protein level by enhanced PSMB8 and PSMB9 protein by Western blotting. As a result, TJP1 suppression was associated with increased activity of the chymotrypsin-like activity of the proteasome, while TJP1 overexpression reduced proteasome activity. A link between TJP1 and PSMB8 and 9 was supported by studies showing that TJP1 influenced activity of EGFR and STAT3 and indeed, EGFR inhibition with erlotinib enhanced PI sensitivity. Consistent with a role for TJP1 in vivo, treatment of mice with bortezomib showed a greater reduction of myeloma growth in tumors with high TJP1 expression compared with isogenic lines with low TJP1 expression. Finally, analysis of the Millennium Pharmaceuticals database of bortezomib studies in the relapsed and relapsed/refractory settings showed high TJP1 expression was associated with a greater likelihood of responding to bortezomib (p<0.0002), and a longer median overall survival (OS)(p=0.008). In addition, in the Total Therapy (TT) databases, higher TJP1 expression was associated with a better progression-free and OS in both TT3a (p=0.004 and <0.0001, respectively), and TT3b (p=0.001 and <0.0001). Conclusions Taken together, these data support the hypothesis that TJP1 modulates PI sensitivity in myeloma through effects on the proteasome’s protein turnover capacity, thereby tilting the load versus capacity balance in favor of cell death. Also, they indicate that strategies targeting TJP1 signaling should be studied as approaches to overcome both primary and secondary resistance. Finally, they support the possibility that TJP1 could be a useful biomarker to identify patients who are most likely to benefit from PI-based therapies, and prospective studies to validate this further are currently underway. Disclosures: Usmani: Celgene: Consultancy, Research Funding, Speakers Bureau; Onyx: Research Funding, Speakers Bureau. Orlowski:Genentech: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Array Biopharma: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Resverlogix: Research Funding; Onyx: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Millennium: The Takeda Oncology Company: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Merck: Membership on an entity’s Board of Directors or advisory committees.
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19

Naomi Sakae, Patricia, Anita L. R Saldanha, Antonio Helfenstein Fonseca, Henrique Trial Bianco, Luciano Monteiro Camargo, Maria Cristina De Oliveira Izar, Ana Paula Pantoja Margeotto, et al. "Traditional weight loss and dukan diets as to nutritional and laboratory results." Journal of Food Science and Nutritional Disorders 1, no. 1 (June 17, 2021): 8–15. http://dx.doi.org/10.55124/jfsn.v1i1.73.

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Background and Aims: Dukan diet, a popular diet with high content of protein and carbohydrate and fat restriction has been widely used for weight loss. We aimed to compare the effects of the Dukan diet with traditional low-calorie diet in nutritional, laboratory and vascular parameters in obese subjects. Methods and Results: Obese subjects classes I or II of both genders, aging 19 to 65 years were allocated into two groups: Traditional low-calorie diet (n=17) and Dukan Diet (n=17). Anthropometric, laboratory and vascular evaluations were performed at baseline, 3, 6 and 12 months. Body composition was evaluated by bioelectric impedance and endothelial function by flow-mediated dilation of the brachial artery, at same times. After 12 months, it was verified that Dukan diet was more effective (p<0.05) than traditional diet for: weight loss (-10.6 vs -2.9 kg), body mass index (-3.7 vs -1.1 kg/m2), waist circumference (-11.2 vs -2.1 cm), fat (-5.7 vs -2.0 kg) and lean mass (-4.8 vs 0.8 kg) and basal metabolic rate (-152 vs -28 cal). In Dukan diet group, improvement (p<0.05 vs baseline) was observed in triglyceride levels (172.40 to 111.90 mg/dL) and insulin resistance, based on HOMA-IR index (4.98 to 3.26). The glomerular filtration rate decreased in this group after 3 months (132.50 to 113.80 mL/min) and no changes in flow-mediated dilation were observed throughout the study with both diets. Conclusion: Dukan diet was more effective than traditional diet for weight loss and laboratory parameters and without changes in endothelial function, in the 12-months follow-up of obese subjects. Introduction Low-carbohydrate diets have been one of the most recently used dietary therapies in patients with diabetes and obesity in clinical studies(1). Among them, in addition to carbohydrate restriction, fat restriction and high protein concentration, as in the Diet Dukan, has been widely used by the general population, aiming at weight loss. The Dukan diet is designed to reduce carbohydrate and fat intake in the first phase of the diet, with exclusive intake of protein, followed by another Three phases, with progressive and slow reintroduction of other nutrients such as fiber, carbohydrates and fats. In recent years, there has been increasing interest in the effectiveness of very low carbohydrate diets, called ketogenic diets, in the effectiveness of weight loss in order to combat obesity and cardiovascular disease risk(2). In this diet, ketone bodies are formed and they are used as an alternative energy source in the absence of glucose. Ketogenic diet promotes weight loss reducing appetite, increasing satiety and thermogenesis, due to the high protein consumption(3) affect hormones that control appetite, such as ghrelin and leptin(4) reduces lipogenesis and increases lipolysis(5,6) and gluconeogenesis(7). Replacing carbohydrates by proteins in the diet have been the aim of several studies but with inconsistent results. High protein intake has positive effects on weight loss, acting on satiety, body composition, lipid profile and glucose homeostasis. Furthermore, it increases thermogenesis, energy expenditure(8) and the elevation in the amino acid level in the plasma acts on the satiety center, decreasing appetite, since amino acids also stimulate insulin secretion resulting in decreased or maintained blood glucose levels(9). Few studies have been published with Dukan diet. Freeman et al. were the first to publish an article with the Dukan Diet in 2014, describing adverse effects in one patient undergoing this diet(10). Nouvenne et al. reviewed studies about the influence of popular diets on kidney stone formation risk. In this article, the authors suggest that in the Dukan diet, due to the high consumption of animal protein, urinary calcium can increase and the citrate urinary excretion can decrease, increasing the risk of kidney stone formation(11). In 2015, Wyka et al. evaluated dietary consumption in women adopting the Dukan-diet, based on the menu consumed in each of 4 phases of diet. They observed weight loss of around 15 kg after 8 to 10 weeks of diet and higher intake of proteins, mainly of animal origin, high consumption of potassium, iron and vitamins A, D and B2 and reduced consumption of carbohydrates, vitamin C and folates. They suggest that this diet may be harmful to health if adopted for a long time, developing of kidney and liver disease, osteoporosis and cardiovascular disease(12). Considering that the Dukan Diet is widely disseminated and it is used by the population in general for weight loss and few scientific studies are found in the literature, we propose to evaluate the nutritional, laboratory parameters related to cardiovascular disease, comparing this diet with traditional hypocaloric diet in obese individuals. Methods Study design This study was a clinical trial with nutritional intervention, for one year. Patients were recruited from the Lipids, Atherosclerosis and Vascular Biology Division of the Universidade Federal de São Paulo (UNIFESP). The study conforms to the ethical guidelines and approval was obtained from the ethics committee and it was registered in the Brazilian Registry of Clinical Trials. All participants provided written informed consent and received no monetary incentive. A total of 40 subjects were initially recruited and the participants were followed up clinically by a cardiologist and nutritionist during the 12-month period with monthly visits. Of the 40 participants who started the study, 34 completed the 12-month follow-up, whose data are presented in this study. The inclusion criteria were: both genders, aging 19-65 years old, obesity grade I or II (body mass index between 30 kg/m² and 39.9 kg/m²), stable body weight in the previous 3 months and desire to lose weight. The main exclusion criteria were: patients in primary or secondary prevention of coronary heart disease with low-density lipoprotein cholesterol (LDL-C) levels greater than 190 mg/dL and triglycerides greater than 400 mg/dL; diabetes mellitus; untreated hypothyroidism; psychiatric and hepatic disease; chronic renal failure; cardiac and respiratory insufficiency; systemic infections; use of antidepressants, corticoids, diuretics and diabetes medications; bariatric surgery, cancer and failure to accept the conditions necessary to conduct the research. Two groups were constituted: Traditional low-calorie diet (TD): n=17, 14 females and 3 males, 45±11 years old, 90±11 Kg body weight and body mass index (BMI) 34±2Kg/m2; High protein/Low carbohydrate diet-Dukan Diet (DD): n=17, 10 females and 7 males, 38±11 years old, 95±9 Kg of body weight and BMI 34±2 Kg/m2. The TD group received orientations according to the Food Guideline for the Brazilian Population, with 1 500–1 800 calories/day. They were stimulated to improve healthy eating habits increasing the consumption of natural foods without preservatives, such as vegetables and fruits rich in fiber and antioxidants. Daily consumption of fruits and vegetables at meals was recommended; carry out the fractionation of the meals throughout the day, avoiding prolonged fasting. Hydration and regular physical activity were recommended, according to healthier life habits(13). The DD group followed the high-protein/low-carbohydrate diet as proposed by Dukan Diet, available at https://www.dietadukan.com.br and received an illustrated book about this diet(14). This diet is structured in four phases: two for weight loss (1st and 2nd phases) and two for weight maintenance (3rd and 4th phases): 1st stage - Attack: For 5 consecutive days, it is allowed to consume only proteins with lean meats, eggs, light cheese and milk, 1.5 tablespoons of oat bran per day and light physical activity for 20 minutes. 2nd stage - Cruise: This phase is maintained until the desired weight loss. The vegetables are introduced alternating with the pure protein day (first stage). It is recommended 2 tablespoons of oat bran per day and light physical activity for 30 minutes. 3rd phase - Consolidation: The time of this phase is equivalent to 10 days per kg of lost weight. In this stage carbohydrates and lipids are introduced by a controlled and moderate way, being divided in two parts: in the first part, corresponding to half of the period to be followed, is allowed: 1 fruit, 2 slices of bread (50 g) or 1 spoon of farinaceous per day and 1 gala dinner per week. In the second part, it is allowed 2 fruits, 4 slices of bread (100 g) or 2 spoons of farinaceous per day and 2 gala dinners per week. This phase has one rule: make one day of the week with pure protein (first stage) and it is recommended 2.5 tablespoons of oat bran per day and light physical activity for 35 minutes. 4th phase - Stabilization: In this phase, three rules must to be followed: one day a week it should follow up the pure protein diet, the daily consumption of 3 tablespoons of oat bran and at least 40 minutes of daily walking. From this phase, the participants followed up the low calorie diet. The adherence of the participants was monitored by the interview with the nutritionist and qualitative evaluation of ketone bodies in the urine, using Labtest UriAction 10 reagent strips. At baseline, 3, 6 and 12 months, the following evaluations were performed: nutritional assessment determining anthropometry, blood samples were collected for laboratory tests. Endothelial function was evaluated in fasting and 2-hours post prandial situations. In the periods between the predetermined visits, the participants were followed up by the nutritionist monthly and by telephone contact whenever requested and with medical attention whenever necessary. Nutritional evaluation Nutritional assessment was performed by anthropometric determinations of weight, height, BMI, abdominal circumference and bioelectric impedance (BIA). BIA was carried out using the Biodynamics Model 450 TBW® apparatus, with portable plethysmograph and patients were instructed according to the manufacturer's instruction(15). Laboratory parameters Peripheral blood samples were collected for dosages of total cholesterol and fractions, triglycerides, glucoses, insulin, iron, ferritin, ALT, AST, urea, creatinine, hemoglobin and hematocrit. Biochemical parameters were determined through the automated colorimetric enzymatic method in Cobas Mira® (Roche, Switzerland) and LDL-c was estimated by the Friedewald equation. Serum insulin concentration was determined by immunofluorometry and the insulin resistance calculated by the HOMA-IR – Homeostasis Model Assessment Insulin Resistance, and values ≥ 2.5 values were considered as presence of insulin resistance(16). Glomerular Filtration Rate (GFR) was estimated by the Cockroft-Gault equation adapted to obese patients(17). Endothelial function Endothelial function was assessed by Endothelial-dependent flow-mediated dilation (FMD) of the brachial artery(18), using an ultrasound system (Sonos5500; Hewlett-Packard-Phillips, Palo Alto, CA), equipped with vascular software for two-dimensional imaging, color and spectral Doppler ultrasound modes, internal electrocardiogram monitor and linear-array transducer with a frequency range from 7.5 to 12.0 MHz. FMD evaluation was performed in two stages: fasted at least 6 hours and 2 hours after the consumption of a small meal, according to each diet. These meals were consisted of 374.04 calories, 36g proteins, 16g carbohydrates and 18g lipids in the DD and in TD, it was composed by 361.20 calories, 24g of protein, 41g of carbohydrates and 11g of lipids. Statistical Analysis The variables were expressed as mean and standard deviation. The distribution of the date normality was analyzed by the Kolmogorov-Smirmov (KS) test. When they did not present normal distribution, a logarithm [log(Y)] transformation was performed prior to analysis. The comparison between the variables of two groups was performed using Student's t-test for independent numerical variables and Fisher's exact test for categorical variables. Comparisons between more than two groups were performed by analysis of variance (ANOVA) for repeated measures, followed by the Tukey test, if differences were found. For the sample power calculation, the Statistical Software, Statistica Ultimate Academic, version 12.7, Concurrent Network was used. Values of p ≤ 0.05 were considered for statistical significance and analysis was performed using the software [GraphPadPrism 4.0 (GraphPad Software, San Diego, CA, USA)]. Results Participants’ characteristics At the beginning of the study, the groups were matched for age, gender, weight and BMI. At 3 months, all participants of DD group (100%) were in phase 2; at 6 months, 13 participants (76.4%) were in phase 3 and 4 (23.5%) in phase 2; and at 12 months, all (100%) were already in phase 4. The TD group followed the same recommendation during the 12 months. The qualitative evaluation of the presence of ketone bodies in the urine of the DD group participants, which were still in phase 2, was positive in 94% at 3rd month and 80% at the 6th month. The following adverse effects have been reported during the course of the study: weakness, fatigue, dizziness, lack of concentration, irritability, constipation, ketone breath and social life impairment. These symptoms were of low intensity and transient, especially in the early stages of the DD diet. These adverse effects were not causes for withdrawal from the study. Anthropometry The changes in body weight, BMI, waist abdominal circumference and BMR were more effective in DD than TD group during all follow-up evaluations. The changes after 12 months in relation to baseline of the anthropometric parameters in the DD and DT groups respectively were: Weight loss (-10.6 Kg, p<0.0001 and – 2.9 Kg, p<0.0001), BMI (-3.7 Kg/m2, p<0.0001 and -1.1 Kg/m2, p<0.0001), waist abdominal circumference (-11.2 cm, p<0.0001 and -2.1 cm, p=0.0008) and BMR (-152 cal, p<0.0001 and -28 cal, p=0.0198). After 12 months, the participants of DD group reached the overweight level but the TD group was still within the obesity range. Reductions were observed in both groups, in fat mass (-5.7 Kg, p<0.0001 and -2.0 Kg, p<0.0001), and in lean mass (-4.8 Kg, p<0.0001 and -0.8 Kg, p=0.0196, in DD and DT group, respectively). Laboratory parameters and endothelial function In TD group, there was only hematocrit reduction after 6 months (p=0.0103) and glucose level after 3 months (p=0.0021) compared to baseline. In DD group, laboratory alterations occurred in relation to hemoglobin, hematocrit, triglycerides, insulin, HOMA-IR and GFR. It was observed an improvement in the triglycerides levels (172.40 ± 62.36 mg/dL and 111.90 ± 43.22 mg/dL, p=0.0001) and insulin resistance determined by HOMA-IR at all times of study (4.98 ± 3.03 and 3.26 ± 2.03, p=0.0008) at baseline and 12 months, respectively. GFR was reduced only after 3 months (132.50 ± 31.13 and 113.80 ± 24.25 mL/min, p=0.0063) in the DD group. No differences were observed in endothelial function in the two study groups, in both fasting and postprandial. Discussion This study demonstrated higher weight loss in the Dukan diet group, compared to the traditional low calorie diet. The effect of weight loss in the DD group was persistent and remained until 6th month, but in 12 months it was observed a gain around 3.41 ± 0.21 Kg. The DD is performed in phases, with severe restriction until the 3rd phase and at about the 6th month; carbohydrates and a gala meal are reintroduced, promoting a weight gain. Sacks et al. observed that regardless of the nutritional composition of the diet, obese participants that had a weight loss, after 12 months of treatment, they can gain weight, but with a reduction of approximately 11.4% of the initial weight(19). We observed that participants of TD group also presented significant weight reduction, suggesting the effectiveness of the close follow up with nutritionist and physician. Abdominal circumference is an indirect parameter of fat mass corresponding to visceral fat that is associated with a higher risk for cardiovascular diseases. In our data, we observed a reduction in waist circumference in both groups after 12 months. Moreno et al. comparing ketogenic diet with standard diet in a group of obese patients found an important reduction in abdominal circumference with partial recovery after 24 months(20). Although DEXA Scan is considered the gold standard for body composition determination, BIA is a non-invasive and relatively inexpensive method and widely used(21). A significant reduction in the relative values of body fat was observed at 3 and 6 months in the DD group and only after 3 months in the TD. Increase in percent of lean mass was observed in the DD group at 3 and 6 months, but this increase does not represent a gain of lean mass, since the relative increase is a result of the reduction of body weight, promoting a relative increase in the values of lean mass. The loss of lean mass in the DD group may be due to the low caloric intake of the diet, as Chaston et al. (2007) pointed out that diet with low-calorie diet promote marked weight loss, but there is a decline in lean mass resulting from this process(22) . In our study, in spite of consuming a large amount of protein, this nutrient alone is not enough to promote the maintenance of lean mass and exercise stimulation is still necessary, which did not happen in this study, since the participants were all sedentary. In obese individuals, weight gain after marked loss is common, with reduction in basal metabolic rate(23). Several studies have observed this phenomenon during rapid weight loss(24) and diets with low carbohydrate intake are among the factors that influence metabolic adaptation. Some studies suggest that low amounts of carbohydrate (<45%) decrease the basal metabolic rate during and after weight loss. This type of diet can promote fat mass loss and preservation of lean mass during weight loss, reducing the basal metabolic rate. Reduction in BMR was observed in both groups, but in the DD group, the reduction occurred at all times in relation to baseline whereas in TD group the reduction was greater only after 6 months of intervention. Improvement in insulin resistance and triglycerides were observed only in the DD group. Individuals with insulin resistance have greater difficulty to metabolize carbohydrates, diverting a greater amount of dietary carbohydrates to the liver, where much of it is converted to fat (lipogenesis), rather than being oxidized in energy in the skeletal muscle. For this reason, very low carbohydrate diets applied in obese individuals, in addition to leading to weight loss also improves glycemic and lipid control. The effects of the very prolonged ketogenic diet are still poorly investigated and for this reason this diet should only be used for a limited period (from 3 weeks to a few months) to stimulate fat loss, improve metabolism, and then adjusting a transition to a normal diet(25). No changes in levels of total cholesterol, HDL-c and LDL-c were observed in any group. However, only in the DD group there was a significant reduction in TG level. In general, diets with reduced carbohydrates and high levels of proteins and fats increase LDL-c and TG levels showing beneficial effects of the ketogenic diet on cardiovascular risk factors. Most studies show that reducing carbohydrates can bring significant benefits in reducing total cholesterol, increases in HDL-c and reduction of triglycerides in the blood. HMG-CoA reductase, a key enzyme in the synthesis of endogenous cholesterol is activated by insulin, so that a reduction in blood glucose and hence insulin levels, leads to lower cholesterol synthesis. Thus, a reduction in dietary carbohydrate associated with adequate cholesterol consumption leads to inhibition of cholesterol biosynthesis(26). When insulin is elevated, lipolysis is reduced and lipogenesis is increased, resulting in overproduction of VLDL containing TG, formation of small and dense LDL particles and reduction of HDL. Low concentrations of glucose and insulin also reduce the expression of the carbohydrate-sensitive response element binding protein (ChREBP) transcription factor, and expression of the binding protein of the sterol regulatory element (SREBP-1c), responsible for the synthesis of fatty acids, as well as their incorporation into triglycerides and phospholipids, activating the main lipogenic enzymes, reducing hepatic lipogenesis and VLDL production(27). When we evaluated the GFR, a reduction only in DD group was observed at 3 months of intervention, but still in normal reference levels. Our results did not show significant changes in serum creatinine levels, but GFR decrease in DD group. Carbohydrate-restricted diets have higher amounts of protein may affect glomerular filtration leading to progressive loss of renal function(28). In the study conducted by Brinkworfh et al. (2010), renal function was evaluated in 68 obese individuals without renal dysfunction who consumed two similar hypocaloric diets for one year, one with carbohydrate reduction and another with high carbohydrate content, and observed that creatinine serum levels and the GFR did not change in any of the dietary groups(29). In general, endothelial function improves after weight loss in obese individuals(30). However, associations between changes in endothelial function with anthropometric and biochemical parameters are still controversial(31). We observed that the endothelial function did not present a significant difference in the two study groups, both in fasting and in the 2 hours postprandial. Volek et al. (2009) observed that low-carbohydrate diet improves postprandial vascular function compared to a low-fat diet in overweight individuals with moderate hypertriglyceridemia(32). Low-carbohydrate diets, may improve vascular function in individuals with metabolic adaptations(32) and carbohydrate-restricted diets may induce benefits in endothelial function in the presence of insulin resistance, since impaired insulin action may be related to endothelial dysfunction. In our study, the meal offered for postprandial evaluation was not high in fat, but correspond to the diet proposed in each group. According to Nicholls et al. (2006), a single carbohydrate-restricted meal does not alter endothelial function(33) and this may be the reason we did not observe a change in endothelial function in the DD group in this study. Conclusion Comparing the nutritional and laboratory effects of traditional and hyper-protein diets with carbohydrate reduction, we can conclude that Dukan diet was more effective than traditional diet for weight loss, as well as for laboratory parameters and without changes in endothelial function, in the 12-months follow-up of obese subjects. Conflict of interest No conflict of interest. Acknowledgement Patricia Naomi Sakae had a scholarship from CAPES – Brazil. References Gogebakan O.; Kohl A.; Osterhoff MA.; van Baak MA.; Jebb SA.; Papadaki A.; et al. Effects of weight loss and long-term weight maintenance with diets varying in protein and glycemic index on cardiovascular risk factors: the diet, obesity, and genes (DiOGenes) study: a randomized, controlled trial. Circulation. 2011, 124(25), 2829-2838. Merino J.; Kones R.; Ferre R.; Plana N.; Girona J.; Aragones G.; et al. Low-carbohydrate, high-protein, high-fat diet alters small peripheral artery reactivity in metabolic syndrome patients. Clin Investig Arterioscler. 2014, 26(2), 58-65. Krieger JW.; Sitren HS.; Daniels MJ.; Langkamp-Henken B. Effects of variation in protein and carbohydrate intake on body mass and composition during energy restriction: a meta-regression 1. Am J Clin Nutr. 2006, 83(2), 260-274. Samaha FF.; Iqbal N.; Seshadri P.; Chicano KL.; Daily DA.; McGrory J.; et al. A low-carbohydrate as compared with a low-fat diet in severe obesity. N Engl J Med. 2003, 348(21), 2074-2081. Paoli A.; Rubini A.; Volek JS.; Grimaldi KA. Beyond weight loss: a review of the therapeutic uses of very-low-carbohydrate (ketogenic) diets. Eur J Clin Nutr. 2013, 67(8), 789-796. Nordmann AJ.; Nordmann A.; Briel M.; Keller U.; Yancy WS, Jr.; Brehm BJ.; et al. Effects of low-carbohydrate vs low-fat diets on weight loss and cardiovascular risk factors: a meta-analysis of randomized controlled trials. Arch Intern Med. 2006, 166(3), 285-293. Veech RL. The therapeutic implications of ketone bodies: the effects of ketone bodies in pathological conditions: ketosis, ketogenic diet, redox states, insulin resistance, and mitochondrial metabolism. Prostaglandins Leukot Essent Fatty Acids. 2004, 70(3), 309-319. Feinman RD.; Fine EJ. Nonequilibrium thermodynamics and energy efficiency in weight loss diets. Theor Biol Med Model. 2007, 4, 27. Veldhorst MA.; Westerterp-Plantenga MS.; Westerterp KR. Gluconeogenesis and energy expenditure after a high-protein, carbohydrate-free diet. Am J Clin Nutr. 2009, 90(3), 519-526. Freeman TF.; Willis B.; Krywko DM. Acute intractable vomiting and severe ketoacidosis secondary to the Dukan Diet(c). J Emerg Med. 2014, 47(4), e109-112. Nouvenne A.; Ticinesi A.; Morelli I.; Guida L.; Borghi L.; Meschi T. Fad diets and their effect on urinary stone formation. Transl Androl Urol. 2014, 3(3), 303-12. 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20

Lijnse, Thomas, Kazim Haider, Catherine Betancourt-Lee, and Colin Dalton. "High Density Cleanroom-Free Microneedle Arrays for Pain-Free Drug Delivery." Journal of Micromechanics and Microengineering, November 22, 2022. http://dx.doi.org/10.1088/1361-6439/aca4da.

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Abstract The purpose of this work is to demonstrate the fabrication process of cleanroom-free solid metal microneedles and quantify their insertion profiles. Metal microneedles were created using a modified wire-bonding process and inserted into porcine tissue to determine the design efficacy. The microneedle arrays were analyzed using optical imaging and SEM. The insertion forces were measured using a combined uniaxial load cell and resistance measurement data. Microneedle arrays were successfully inserted into porcine tissues with high repeatability and reliability. These arrays demonstrate lower or equivalent insertion forces (less than 3 N) to other forms of microneedles in the literature, without the need for complex cleanroom fabrication processes. The microneedle fabrication method presented here rapidly produces mass-manufacturable, high-quality microneedle arrays with minimal insertion forces that can reliably penetrate tissue samples. The manufacturing method presented here achieved array densities as high as 3200 needles per square centimeter. These microneedle arrays demonstrate the simple fabrication of a reliable, high-density, pain-free drug delivery system with potential applications in biosensing and electric-field-modulated drug delivery.
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21

Chang, Wen-Sheng, Wei-Kuang Liang, Dong-Han Li, Neil G. Muggleton, Prasad Balachandran, Norden E. Huang, and Chi-Hung Juan. "The association between working memory precision and the nonlinear dynamics of frontal and parieto-occipital EEG activity." Scientific Reports 13, no. 1 (August 31, 2023). http://dx.doi.org/10.1038/s41598-023-41358-0.

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AbstractElectrophysiological working memory (WM) research shows brain areas communicate via macroscopic oscillations across frequency bands, generating nonlinear amplitude modulation (AM) in the signal. Traditionally, AM is expressed as the coupling strength between the signal and a prespecified modulator at a lower frequency. Therefore, the idea of AM and coupling cannot be studied separately. In this study, 33 participants completed a color recall task while their brain activity was recorded through EEG. The AM of the EEG data was extracted using the Holo-Hilbert spectral analysis (HHSA), an adaptive method based on the Hilbert-Huang transforms. The results showed that WM load modulated parieto-occipital alpha/beta power suppression. Furthermore, individuals with higher frontal theta power and lower parieto-occipital alpha/beta power exhibited superior WM precision. In addition, the AM of parieto-occipital alpha/beta power predicted WM precision after presenting a target-defining probe array. The phase-amplitude coupling (PAC) between the frontal theta phase and parieto-occipital alpha/beta AM increased with WM load while processing incoming stimuli, but the PAC itself did not predict the subsequent recall performance. These results suggest frontal and parieto-occipital regions communicate through theta-alpha/beta PAC. However, the overall recall precision depends on the alpha/beta AM following the onset of the retro cue.
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22

Kim, Elliot W., Santhosh M. Nadipuram, Ashley L. Tetlow, William D. Barshop, Philip T. Liu, James A. Wohlschlegel, and Peter J. Bradley. "The Rhoptry Pseudokinase ROP54 Modulates Toxoplasma gondii Virulence and Host GBP2 Loading." mSphere 1, no. 2 (March 23, 2016). http://dx.doi.org/10.1128/msphere.00045-16.

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ABSTRACT The interactions between intracellular microbes and their host cells can lead to the discovery of novel drug targets. During Toxoplasma infections, host cells express an array of immunity-related GTPases (IRGs) and guanylate binding proteins (GBPs) that load onto the parasite-containing vacuole to clear the parasite. To counter this mechanism, the parasite secretes effector proteins that traffic to the vacuole to disarm the immunity-related loading proteins and evade the immune response. While the interplay between host IRGs and Toxoplasma effector proteins is well understood, little is known about how Toxoplasma neutralizes the GBP response. We describe here a T. gondii pseudokinase effector, ROP54, that localizes to the vacuole upon invasion and is critical for parasite virulence. Toxoplasma vacuoles lacking ROP54 display an increased loading of the host immune factor GBP2, but not IRGb6, indicating that ROP54 plays a distinct role in immune evasion. Toxoplasma gondii uses unique secretory organelles called rhoptries to inject an array of effector proteins into the host cytoplasm that hijack host cell functions. We have discovered a novel rhoptry pseudokinase effector, ROP54, which is injected into the host cell upon invasion and traffics to the cytoplasmic face of the parasitophorous vacuole membrane (PVM). Disruption of ROP54 in a type II strain of T. gondii does not affect growth in vitro but results in a 100-fold decrease in virulence in vivo, suggesting that ROP54 modulates some aspect of the host immune response. We show that parasites lacking ROP54 are more susceptible to macrophage-dependent clearance, further suggesting that ROP54 is involved in evasion of innate immunity. To determine how ROP54 modulates parasite virulence, we examined the loading of two known innate immune effectors, immunity-related GTPase b6 (IRGb6) and guanylate binding protein 2 (GBP2), in wild-type and ∆rop54II mutant parasites. While no difference in IRGb6 loading was seen, we observed a substantial increase in GBP2 loading on the parasitophorous vacuole (PV) of ROP54-disrupted parasites. These results demonstrate that ROP54 is a novel rhoptry effector protein that promotes Toxoplasma infections by modulating GBP2 loading onto parasite-containing vacuoles. IMPORTANCE The interactions between intracellular microbes and their host cells can lead to the discovery of novel drug targets. During Toxoplasma infections, host cells express an array of immunity-related GTPases (IRGs) and guanylate binding proteins (GBPs) that load onto the parasite-containing vacuole to clear the parasite. To counter this mechanism, the parasite secretes effector proteins that traffic to the vacuole to disarm the immunity-related loading proteins and evade the immune response. While the interplay between host IRGs and Toxoplasma effector proteins is well understood, little is known about how Toxoplasma neutralizes the GBP response. We describe here a T. gondii pseudokinase effector, ROP54, that localizes to the vacuole upon invasion and is critical for parasite virulence. Toxoplasma vacuoles lacking ROP54 display an increased loading of the host immune factor GBP2, but not IRGb6, indicating that ROP54 plays a distinct role in immune evasion.
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23

Wang Liang-Wei, Liu Fang-De, Li Yun-Da, Han Wei, Meng Zeng-Ming, and Zhang Jing. "Construction of 2D <sup>87</sup>Rb atomic array of multi arbitrary geometries with SLM." Acta Physica Sinica, 2023, 0. http://dx.doi.org/10.7498/aps.72.20222096.

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The ultra-cold atomic system is a clean and highly controllable quantum system, which can be used for quantum simulation of important physical problems in many fields such as condensed matter physics, high-energy physics, astrophysics and chemical reactions. The construction of optical lattices with different configurations is an important prerequisite for simulating diverse complex quantum systems, especially solid materials. In this paper, we use weighted GerchbergSaxton (GSW) algorithm to generate holograms. By using liquid crystal spatial light modulator and high-resolution imaging system, holograms (in momentum space) are transformed into real space for constructing various 2D optical trap arrays, such as simple triangular, hexagonal, square lattice and more complex honeycomb lattice. We load 87Rb ultra-cold atoms into the 2D optical trap arrays with a minimal spacing of 3 μm. This method is versatile and flexible, which is helpful to expand the application of quantum simulation with optical lattices.
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24

Jin, Yaqing, Shyuan Cheng, and Leonardo P. Chamorro. "On the impact of layout in the dynamics of wind turbine arrays under passive oscillations." Journal of Renewable and Sustainable Energy, May 25, 2022. http://dx.doi.org/10.1063/5.0095420.

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Laboratory experiments were performed to explore the layout effect on the multiscale motions of wind turbines able to oscillate passively and the impact on power output fluctuations, which is instrumental towards understanding the dynamics of floating turbine arrays. We studied 3$\times$3 and 3$\times$5 turbine arrays in aligned and staggered configurations with inter-row separations of $S_x/d_T=5$ and 10 sharing transverse spacing of $S_y/d_T=2.5$. Three-axis accelerometer characterized turbines' oscillations, whereas power output was obtained directly. Particle image velocity was used to monitor eventual flow irregularities. The standard deviation of pitch angle, $A_p$($^\circ$) about the equilibrium, obtained from direct integration of instantaneous angular velocity, shows that the turbines underwent relatively small-amplitude pitch motions with maximum intensity monotonically decreasing with increasing row location in the aligned layout. However, this was not the case in the staggered configurations; indeed, the second row of turbines underwent larger pitch amplitude in the $S_x/d_T=10$ case. Flow channeling and larger turbine spacing promote the development and entrainment of large coherent motions producing larger unsteady forcing, triggering enhanced turbine motions. The instantaneous pitching angle density distribution exhibited Gaussian-like distribution irrespective of the units' location. A formulation for turbine pitching motions based on the balance between wind load restoring force and gravity shows that the bulk natural frequency modulates the turbine pitching angular velocity. The variation of turbine pitching amplitudes was similar to those of the mean power output. The power output spectra evidenced modulation of the local turbulence and turbine pitching natural frequency due to the flow-induced turbine pitching motions.
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