Articles de revues : « Duration matrix »

1

Okuyama, Toshinori. « Stage duration distributions in matrix population models ». Ecology and Evolution 8, n^o 16 (16 juillet 2018) : 7936–45. http://dx.doi.org/10.1002/ece3.4279.

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Singer, Harald, et Shigeki Sagayama. « Suprasegmental duration control with matrix parsing in continuous speech recognition ». Speech Communication 13, n^o 3-4 (décembre 1993) : 315–22. http://dx.doi.org/10.1016/0167-6393(93)90030-o.

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Mannor, Shie, et Nahum Shimkin. « Regret minimization in repeated matrix games with variable stage duration ». Games and Economic Behavior 63, n^o 1 (mai 2008) : 227–58. http://dx.doi.org/10.1016/j.geb.2007.07.006.

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Okuyama, Toshinori. « Census timing alters stage duration distributions in matrix population models ». Ecology and Evolution 9, n^o 15 (9 juillet 2019) : 8500–8508. http://dx.doi.org/10.1002/ece3.5315.

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Maier, Petra, Merle Schmahl, Benjamin Clausius, Charis Joy et Claudia Fleck. « Nanoindentation on the Transformation of LPSO Phases during Different Solution Heat Treatments in an Mg-Dy-Nd-Zn-Zr Alloy ». Crystals 12, n^o 11 (20 novembre 2022) : 1673. http://dx.doi.org/10.3390/cryst12111673.

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The objective of this study is the investigation of nanomechanical properties using nanoindentation of extruded and heat-treated Mg-Dy-Nd-Zn-Zr, with an emphasis on the transformation of long-period stacking-ordered (LPSO) phases. Solution heat treatment was performed with different heat treatment for durations on hot extruded Mg-Dy-Nd-Zn-Zr to monitor the transformation of LPSO phases, as well as to keep track of microstructural changes. The initial fine-grained microstructure, with blocky and lamellar LPSO structures within the matrix, first transformed into coarser grains with fewer LPSO lamellae, which then increased in amount again at higher annealing duration. The blocky LPSO phases, which have the highest hardness compared to the matrix grains with and without LPSO lamellae, consistently decrease in quantity, as so does the trend in their hardness value. The Mg matrix grains with LPSO lamellae show a lower hardness compared to the Mg matrix grains without or with a just few lamellar LPSO phases, and increase in quantity at long annealing durations. The overall hardness of the microstructure is essentially determined by the LPSO lamellae-containing grains and reaches a peak at 24 h. There is another peak found for the grain size values; however, this is at later annealing duration, at 72 h. The reduction in grain size towards longer annealing durations goes along with a reactivated formation of LPSO lamellae.

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Li, Tao, Wen Ge Qiu, Li Chuan Wang et Shuai Man. « Study of Project Duration Risk in the Network Diagram Based on Matrix Algorithm ». Applied Mechanics and Materials 405-408 (septembre 2013) : 3401–5. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.3401.

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The probable route sets in the network diagram were calculated by adjacency matrix method, and based on the assumption that activity becoming the key obeyed 0-1 distribution, a probable route matrix was established. A random variable matrix was structed by monte carlo simulation under condition of activity time independent distribution. A matrix algorithm model was built by isolating activity times impact on activity becoming the key for the first time. This model with a simple and optimal algorithm avoided the computation complexity of network planning time parameter, to evaluate project duration risk rapidly and statistical analyze the probability of activity becoming the key and the influence degree of activity time fluctuation impacting on project duration, providing theoretical and data support for decisions. Empirical research on a tunnel engineering project verified its practicability and feasibility, providing a new powerful tool for assessing project duration risk in the network diagram quickly.

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Mardin, H., I. N. G. Wardana, Kamil Kusno, Pratikto et S. Wahyono. « Sea Water Effects on Surface Morphology and Interfacial Bonding of Sugar Palm Fiber to Sago Matrix ». Key Engineering Materials 724 (décembre 2016) : 39–42. http://dx.doi.org/10.4028/www.scientific.net/kem.724.39.

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Effects of sea water immersion for palm fiber in relation to surface morphology, roughness and bonding between the fiber and sago matrix were observed. Duration of immersion varied in 1, 2, 3 and 4 weeks, and then dried at room temperature for 3 hours continued by oven at 80 °C for 6 hours. SEM and roughness arithmetic tests were applied to see surface morphology, roughness and bonding between fiber and the matrix. Result shows fiber morphology and roughness varies by the duration of immersion. The surface roughness increases as immersion continues along with fiber - matrix bonding improvement. The maximum duration of 4 weeks fiber immersion resulted in the best interlocking of matrix and fibers, as the slits between them disappear.

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Cole, Azadeh D., John Blackwell, Stephanie A. Montgomery, Thomas M. Egan et Marie Muller. « Using random matrix theory to quantify pulmonary fibrosis : Investigating the effect of time window duration ». Journal of the Acoustical Society of America 152, n^o 4 (octobre 2022) : A292. http://dx.doi.org/10.1121/10.0016319.

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Random matrix theory (RMT) exploits the distribution of singular values of the inter-element response matrix (IRM). If multiple scattering dominates the propagation, the singular value distribution follows the quarter circle law. However, dominance of single scattering results in Henkel function behavior of the singular value distribution. In our previous work, we have shown that this can be exploited to estimate severity of bleomycin-induced fibrosis (measured by histology) in rodent lungs. We showed that E( x), the expected value of the singular value distribution, as well as the singular value with the highest probability, correlated significantly with histology scores. Here, we investigate the sensitivity of these metrics to the time window duration used for the Singular Value Decomposition of the IRM, which is performed in the frequency domain, using overlapping time windows. A linear transducer with a central frequency of 7.8 MHz and a Verasonics scanner were used to obtain IRMs in 24 rat lungs. Different degrees of pulmonary fibrosis were induced using bleomycin in 18 rats while 6 rats were left as controls. The IRMs were time-windowed with different duration of 2T, 4T, and 6T where T is the transmitted pulse period. E(x) and were evaluated for each time window duration for all rat lungs. For all time window durations significant correlations were observed between and E(x), and histology scores. Wilcoxon ranksum tests show that the distributions obtained for and E(x) are not affected by the time window duration.

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Wethers, DL, GM Ramirez, M. Koshy, MH Steinberg, G. Jr Phillips, RS Siegel, JR Eckman et JT Prchal. « Accelerated healing of chronic sickle-cell leg ulcers treated with RGD peptide matrix. RGD Study Group ». Blood 84, n^o 6 (15 septembre 1994) : 1775–79. http://dx.doi.org/10.1182/blood.v84.6.1775.1775.

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Abstract Leg ulcers are a chronic manifestation of sickle-cell disease (SCD) and are often painful, disabling, and difficult to treat. RGD peptide matrix treatment is a novel therapy designed to provide a topical synthetic extracellular matrix that can act as a temporary substitute for the damaged natural matrix at the ulcer site. In this randomized, placebo-controlled, double-blind, prospective, multicenter investigation, SCD patients with full-thickness leg ulcers were treated with standard therapy plus RGD peptide matrix or saline placebo once weekly for up to 10 weeks. Healing in patients with chronic ulcers (2 months or greater in duration) was significantly accelerated (P = .0085) in RGD peptide matrix recipients compared with the placebo group. In these chronic ulcer cases, the average percent ulcer closure (decrease in ulcer surface area) in the RGD peptide matrix group (54.4% +/- 8.9%) exceeded that in the placebo group (19.0% +/- 24.3%) nearly threefold by study endpoint. Furthermore, RGD peptide matrix was equally effective in promoting healing of long persistent ulcers and ulcers of shorter duration. In contrast, standard therapy plus placebo was significantly less effective (P = .001) in promoting healing for ulcers of progressively greater duration. The results of this study provide preliminary evidence that RGD peptide matrix treatment may significantly accelerate healing of chronic sickle-cell leg ulcers.

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Wethers, DL, GM Ramirez, M. Koshy, MH Steinberg, G. Jr Phillips, RS Siegel, JR Eckman et JT Prchal. « Accelerated healing of chronic sickle-cell leg ulcers treated with RGD peptide matrix. RGD Study Group ». Blood 84, n^o 6 (15 septembre 1994) : 1775–79. http://dx.doi.org/10.1182/blood.v84.6.1775.bloodjournal8461775.

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Leg ulcers are a chronic manifestation of sickle-cell disease (SCD) and are often painful, disabling, and difficult to treat. RGD peptide matrix treatment is a novel therapy designed to provide a topical synthetic extracellular matrix that can act as a temporary substitute for the damaged natural matrix at the ulcer site. In this randomized, placebo-controlled, double-blind, prospective, multicenter investigation, SCD patients with full-thickness leg ulcers were treated with standard therapy plus RGD peptide matrix or saline placebo once weekly for up to 10 weeks. Healing in patients with chronic ulcers (2 months or greater in duration) was significantly accelerated (P = .0085) in RGD peptide matrix recipients compared with the placebo group. In these chronic ulcer cases, the average percent ulcer closure (decrease in ulcer surface area) in the RGD peptide matrix group (54.4% +/- 8.9%) exceeded that in the placebo group (19.0% +/- 24.3%) nearly threefold by study endpoint. Furthermore, RGD peptide matrix was equally effective in promoting healing of long persistent ulcers and ulcers of shorter duration. In contrast, standard therapy plus placebo was significantly less effective (P = .001) in promoting healing for ulcers of progressively greater duration. The results of this study provide preliminary evidence that RGD peptide matrix treatment may significantly accelerate healing of chronic sickle-cell leg ulcers.

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Mardin, H., I. N. G. Wardana, Pratikto, Wahyono Suprapto et Kusno Kamil. « Effect of Sugar Palm Fiber Surface on Interfacial Bonding with Natural Sago Matrix ». Advances in Materials Science and Engineering 2016 (2016) : 1–5. http://dx.doi.org/10.1155/2016/9240416.

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Palm fibers were immersed in sea water for 1, 2, 3, and 4 weeks prior to application as reinforcement of green biocomposite. Instead of common resin matrix, natural sago starch was applied as the matrix compound. The immersion treatments had significantly affected fibers surface morphology and interfacial bonds of fiber and the matrix as observed through Scanning Electron Microscopy (SEM). The quality of interfacial bonds became higher by additional duration of the sea water immersion. The best interlocking surfaces of fibers and matrix appeared in the composite with 4-week immersed fibers, indicated by disappearance of gaps between fiber and matrix. The morphology of fibers surface interlocking process was clearly seen during the duration of immersion.

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Mandara, M. T., S. Pavone, L. Mandrioli, G. Bettini, C. Falzone et M. Baroni. « Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9 Expression in Canine and Feline Meningioma ». Veterinary Pathology 46, n^o 5 (9 mars 2009) : 836–45. http://dx.doi.org/10.1354/vp.08-vp-0185-m-fl.

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Fifty-one meningiomas obtained from 28 dogs and 23 cats were selected for this study to investigate the immunohistochemical expression of matrix metalloproteinase (MMP)-2 and MMP-9 and to compare it to the reverse transcriptase subunit of human-telomerase, progesterone receptor expression, and the proliferative index of the tumors, expressed by Ki67 and proliferating cellular nuclear antigen. Paraffin-embedded tumor tissue was obtained from biopsy samples (28 cases) and at necropsy (23 cases). The most common histotype was malignant in dogs (12/28) and transitional in cats (12/23). Slides immunolabelled for MMPs showed a diffuse cytoplasmic pattern. Twenty-one cases (19 dogs and 2 cats) did not express MMP-2, while only 2 cases were completely negative for MMP-9. The highest values of MMP-2 and MMP-9 were observed in a psammomatous and meningothelial tumor, respectively. On statistical analysis, MMP-2 expression did not show a significant correlation with MMP-9. Moreover, both MMP expressions failed to show significant variance among histologic patterns of the tumor and correlation with the proliferative index. MMP immunolabeling showed an inconstant correlation with progesterone receptor expression. No significant correlation was found between MMP and reverse transcriptase subunit of human-telomerase expression. In feline meningiomas, the MMP-2 value was significantly higher than in canine tumors and the MMP-9 value tended to be low for meningiomas with a follow-up duration from the 23rd month to the 44th month. In cats, the longer the time from surgery, the lower the proliferative index seemed to be. In dogs, we failed to find a correlation between MMP expression and the follow-up duration.

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Lee, Chih-Chung, et Toshinori Okuyama. « Individual variation in stage duration in matrix population models : Problems and solutions ». Biological Control 110 (juillet 2017) : 117–23. http://dx.doi.org/10.1016/j.biocontrol.2017.04.011.

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Vasil'chenko, V. P., A. K. Kask, L. L. Matizen et M. A. Voikhanskii. « Selecting the duration of excitation pulses for an electroluminescent thin-film matrix ». Soviet Physics Journal 30, n^o 12 (décembre 1987) : 1048–50. http://dx.doi.org/10.1007/bf00897920.

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Amalia, Ariani, M. Dachyar et Farizal. « Scheduling of Aircraft Design Project : A Comparison of Critical Path Method, Design Structure Matrix and Genetic Algorithm Approaches ». MATEC Web of Conferences 248 (2018) : 03011. http://dx.doi.org/10.1051/matecconf/201824803011.

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The purpose of this study to minimize the overall duration of aircraft design project in Indonesia. This study proposes a combination method of Design Structure Matrix (DSM) and Genetic Algorithm (GA) for scheduling aircraft design project activities. DSM is used to identify the information flow between project activities. GA use reworks data, which was the result output of DSM, and activity duration to optimize the task sequence by considering the human resource constraints. A comparative analysis was conducted between the schedule based on DSM and GA and schedule based on Critical Path Method. Combination of DSM and GA obtained 63 days shorter project durations compared to CPM. This research is convenient for design projects scheduling with limited resources that can be obtained by using alternative methods other than traditional methods.

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Li, Zhaoxuan, Derrick Tate, Thomas McGill, John Griswold et Ming-Chien Chyu. « Application of Design Structure Matrix to Simulate Surgical Procedures and Predict Surgery Duration ». Minimally Invasive Surgery 2021 (6 décembre 2021) : 1–12. http://dx.doi.org/10.1155/2021/6340754.

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Background. The complexities of surgery require an efficient and explicit method to evaluate and standardize surgical procedures. A reliable surgical evaluation tool will be able to serve various purposes such as development of surgery training programs and improvement of surgical skills. Objectives. (a) To develop a modeling framework based on integration of dexterity analysis and design structure matrix (DSM), to be generally applicable to predict total duration of a surgical procedure, and (b) to validate the model by comparing its results with laparoscopic cholecystectomy surgery protocol. Method. A modeling framework is developed through DSM, a tool used in engineering design, systems engineering and management, to hierarchically decompose and describe relationships among individual surgical activities. Individual decomposed activities are assumed to have uncertain parameters so that a rework probability is introduced. The simulation produces a distribution of the duration of the modeled procedure. A statistical approach is then taken to evaluate surgery duration through integrated numerical parameters. The modeling framework is applied for the first time to analyze a surgery; laparoscopic cholecystectomy, a common surgical procedure, is selected for the analysis. Results. The present simulation model is validated by comparing its results of predicted surgery duration with the standard laparoscopic cholecystectomy protocols from the Atlas of Minimally Invasive Surgery with 2.5% error and that from the Atlas of Pediatric Laparoscopy and Thoracoscopy with 4% error. Conclusion. The present model, developed based on dexterity analysis and DSM, demonstrates a validated capability of predicting laparoscopic cholecystectomy surgery duration. Future studies will explore its potential applications to other surgery procedures and in improving surgeons’ performance and training novices.

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Ma, Bao Ji, Yu Quan Zhu et Xiao Li Jin. « Wire Electro Discharge Machining of Al/SiC Metal Matrix Composite ». Applied Mechanics and Materials 121-126 (octobre 2011) : 564–67. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.564.

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The machining characteristics of SiC/Al composite using wire electro discharge machining (WEDM) were investigated in this study. Material cutting speed and surface roughness value were adopted to evaluate the machinability. Peak current, pulse on time, pulse duration and working voltage were selected as the input variables to investigate the machining performance. Effects of input variables on the cutting speed and surface roughness were experimentally tested. Peak current, pulse on time and working voltage were confirmed to have positive effects on cutting speed and surface roughness value. Whereas the cutting speed and surface roughness value decrease with the increase of pulse duration.

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Nawata, Shinya, Atsuto Maki et Takashi Hikihara. « Power packet transferability via symbol propagation matrix ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 474, n^o 2213 (mai 2018) : 20170552. http://dx.doi.org/10.1098/rspa.2017.0552.

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A power packet is a unit of electric power composed of a power pulse and an information tag. In Shannon’s information theory, messages are represented by symbol sequences in a digitized manner. Referring to this formulation, we define symbols in power packetization as a minimum unit of power transferred by a tagged pulse. Here, power is digitized and quantized. In this paper, we consider packetized power in networks for a finite duration, giving symbols and their energies to the networks. A network structure is defined using a graph whose nodes represent routers, sources and destinations. First, we introduce the concept of a symbol propagation matrix (SPM) in which symbols are transferred at links during unit times. Packetized power is described as a network flow in a spatio-temporal structure. Then, we study the problem of selecting an SPM in terms of transferability, that is, the possibility to represent given energies at sources and destinations during the finite duration. To select an SPM, we consider a network flow problem of packetized power. The problem is formulated as an M-convex submodular flow problem which is a solvable generalization of the minimum cost flow problem. Finally, through examples, we verify that this formulation provides reasonable packetized power.

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Prasan, Ananth M., Hugh C. K. McCarron, Melanie Y. White, Susan V. McLennan, Adrian S. Tchen, Brett D. Hambly et Richmond W. Jeremy. « Duration of ischaemia determines matrix metalloproteinase-2 activation in the reperfused rabbit heart ». PROTEOMICS 2, n^o 9 (septembre 2002) : 1204–10. http://dx.doi.org/10.1002/1615-9861(200209)2:9<1204 ::aid-prot1204>3.0.co;2-k.

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Brock, Judith, Julia Erhardt, Stephan A. Eisler et Marcel Hörning. « Optimization of Mechanosensitive Cross-Talk between Matrix Stiffness and Protein Density : Independent Matrix Properties Regulate Spreading Dynamics of Myocytes ». Cells 11, n^o 13 (5 juillet 2022) : 2122. http://dx.doi.org/10.3390/cells11132122.

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Cells actively sense differences in topology, matrix elasticity and protein composition of the extracellular microenvironment and adapt their function and morphology. In this study, we focus on the cross-talk between matrix stiffness and protein coating density that regulates morphology and proliferation dynamics of single myocytes. For this, C2C12 myocytes were monitored on L-DOPA functionalized hydrogels of 22 different elasticity and fibronectin density compositions. Static images were recorded and statistically analyzed to determine morphological differences and to identify the optimized extracellular matrix (ECM). Using that information, selected ECMs were used to study the dynamics before and after cell proliferation by statistical comparison of distinct cell states. We observed a fibronectin-density-independent increase of the projected cell area until 12 kPa. Additionally, changes in fibronectin density led to an area that was optimum at about 2.6 μg/cm2, which was confirmed by independent F-actin analysis, revealing a maximum actin-filament-to-cell-area ratio of 7.5%. Proliferation evaluation showed an opposite correlation between cell spreading duration and speed to matrix elasticity and protein density, which did not affect cell-cycle duration. In summary, we identified an optimized ECM composition and found that independent matrix properties regulate distinct cell characteristics.

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Tee, Tiam Ting, Soo Tueen Bee, Tin Sin Lee, Chantara Thevy Ratnam, Haraveen Kaur Jogindar Singh et Chong Yu Low. « Effect of Aging in Acidic Condition on Mechanical Properties of Copper (II) Oxide Added LDPE Composites ». Applied Mechanics and Materials 786 (août 2015) : 8–12. http://dx.doi.org/10.4028/www.scientific.net/amm.786.8.

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In this work, the effect of aging duration time and copper (II) oxide loading level on the physico-mechanical properties of copper (II) oxide added LDPE composites have been investigated. The addition of copper (II) oxide particles in LDPE matrix has significantly decreased the tensile strength of LDPE composites. The occurrence of copper (II) oxide particles in LDPE matrix could reduce the matrix continuities of copper (II) oxide added LDPE composites by the agglomeration of copper (II) oxide particles. This could further cause the applied straining stress unable to be effectively transferred throughout the whole polymer matrix. The increasing of aging time duration up to 8 days has slightly reduced the tensile strength of all copper (II) oxide added LDPE composites. The increasing of copper (II) oxide loading level has significantly decreased the elongation at break of LDPE composites. This is due to poor interfacial adhesion between copper (II) oxide particles and LDPE matrix could further restrict the mobility of LDPE chains under straining stress and thus decrease the elongation at break.

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Linna, Du, Liu Enwei, Wang Jiaxia et Cui Yifeng. « Analysis of Oral Carcinogenesis Factors Based on Non Negative Matrix Evolutionary Spectrum Clustering Decomposition ». Journal of Medical Imaging and Health Informatics 10, n^o 9 (1 août 2020) : 2016–21. http://dx.doi.org/10.1166/jmihi.2020.3126.

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To explore the risk factors of Oral Submucosal fibrous carcinogenesis and provide theoretical basis for selfprevention and clinical treatment. First of all, an evolutionary non negative matrix factorization framework based on clustering quality is proposed for dynamic oral carcinogenesis detection. Then, the equivalence among evolutionary spectral clustering, ENMF and density optimization of evolutionary modules is proved theoretically. At the same time, based on this equivalence, a new semi-supervised ENMF algorithm is proposed by adding a priori information to ENMF without increasing the time complexity. Using this algorithm, 42 patients with Oral Submucosal Fibrosis and 40 non-cancerous patients with oral submucosal fibrosis were analyzed by single factor and multi-factor analysis to study the quantitative relationship between Oral Submucosal Fibrosis and 14 related factors. The results suggested that age, betel nut chewing duration, smoking duration and leukoplakia or lichen planus were the four factors which were introduced into the cluster quality analysis. Age, betel nut chewing duration, smoking duration and complications of leukoplakia or lichen planus are risk factors for Oral Submucosal fibrous carcinogenesis.

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Mîtcă, Luisa N., Mustafa Günay, Radu Liviu Orban et Ulvi Şeker. « A Study on the Effect of Manufacturing Conditions on Surface Roughness during Machining of Cu/Al₂O₃ Composites ». Materials Science Forum 672 (janvier 2011) : 263–70. http://dx.doi.org/10.4028/www.scientific.net/msf.672.263.

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In this study, the machinability of the Cu matrix composites reinforced with 5, 10, 15 and 20 vol.% of Al2O3 particulates produced by powder metallurgy have been investigated. The effects of compaction pressure, sintering duration and volume fraction of reinforcing component on the surface roughness during machining of the considered composites, obtained by the appropriate Cu-Al2O3 powder mixtures cool die pressing at 500, respectively 700 MPa, and sintered at 800 °C for durations of 45 and 60 minutes in an argon atmosphere were determined. The machining tests were performed on a CNC machining centre, by means of samples face milling in dry conditions, at two different feed rates and four different cutting speeds, while the depth of cut was kept constant. As cutting tools have been adopted commercial grade (H13A) uncoated cemented carbide inserts manufactured by Sandvik Coromant with the geometry of TPKN1603 PP-R. After the machining tests, the surface roughness measurements clearly showed an increasing trend in surface roughness when the feed rate is increased from 300 mm/min to 400 mm/min for both sintering durations. Surface damages created on the machined surface through release from the matrix of particles negatively impact surface roughness. The most stable results in terms of surface roughness were obtained at 20% reinforcing ratio for 700 MPa compacting pressure and 60 minutes sintering duration.

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Chen, Zhao Xia, Wen Yi Peng, Gui Li Qu, Wei Wei Wang, Hai Ping Shi et Wen Jun Wang. « Effect of Aging on Super-Elastic Response of a Polycrystalline FeNiCoAlNbB Shape Memory Alloy ». Materials Science Forum 787 (avril 2014) : 281–87. http://dx.doi.org/10.4028/www.scientific.net/msf.787.281.

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This study reports the effect of aging duration on the super-elastic response of Fe-30%Ni-18%Co-10.5%Al-2%Nb-0.15%B (at.%) poly-crystals in compression. The aging temperature was 600°C and the aging durations were 20h, 45h, 60h and 72h, respectively. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) were used in the work. The results show that with prolonging the aging duration, the super-elastic strain rises firstly and then descends. The super-elastic strain reaches the maximum 10.5% when the aging duration is 60h. The crisis stress for stress-induced martensite (σM) has no obvious changes, being about 250MPa when the aging duration is between 20h and 60h. But σM increases markedly when the aging duration prolongs to 72h. The hardness of the specimens changes in the same way as the superelastic strain, and reaches the maximum of 497HV10 when the aging duration is 60h. During the aging process, two factors react. One is the decomposing and reducing in size of the undissolved phase (σ). The other is the formation of the precipitation phase (γ'). Nb can dissolve into the matrix phase (γ) adequately and promote the formation of γ'. The combination of the two factors improves the strength and superelasticity of the specimens till the over-aging arises corresponding to the 72h aging duration.

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Eudier, H., S. Ben-Harb, J. P. Lorand, F. Duthil, M. Negahban, J. M. Saiter et M. Chan-Huot. « Properties Of An Analogue Cheese Obtained From Raw Peanut ». Peanut Science 47, n^o 2 (28 mai 2020) : 81–88. http://dx.doi.org/10.3146/ps20-1.1.

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ABSTRACT The focus is on a peanut suspension in which starch is added and that exhibits specific mechanical characteristics relevant for food products. The mixture is composed of water, lipids, starch, and proteins. The process consists of blending together the different constituents, and the study changes the experimental conditions to tune the mechanical behavior of the mixture. The rheological properties (viscosity, indentation) and physical parameters such as color, dry extract, and particle size distribution were measured. The matrix behavior was studied after a centrifugation step necessary to determine stability of the emulsion, and for varying shearing durations. Short shearing duration induce a maximum of firmness, observed by measuring indentation resistance, and a maximum of spreadability, evaluated by shear rheometry. On the contrary, long shearing durations destabilize the matrix emulsion by increasing the oil separation capacity. This study observes structural changes in the rheological behavior of this analogue artificial cheese that correlates with the extent of shearing.

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Mennella, Jenna M., Lori A. Underhill, Sophia Collis, Geralyn M. Lambert-Messerlian, Richard Tucker et Beatrice E. Lechner. « Serum Decorin, Biglycan, and Extracellular Matrix Component Expression in Preterm Birth ». Reproductive Sciences 28, n^o 1 (17 août 2020) : 228–36. http://dx.doi.org/10.1007/s43032-020-00251-1.

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AbstractPreterm birth is a leading cause of infant morbidity and mortality. Decorin and biglycan are proteoglycans that play key roles in maintaining the connective tissue matrix and tensile strength of human fetal membranes and have been previously linked to PPROM. Extracellular matrix proteins, such as matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9), TIMP metallopeptidase inhibitor 1 (TIMP-1), TIMP metallopeptidase inhibitor 2 (TIMP-2), and collagen VI (COL-6), have also been linked to PPROM and may have utility in a serum-based screening model for this condition. To define the natural course of serum decorin and biglycan expression throughout the duration of healthy pregnancy, to explore patterns of serum decorin and biglycan expression in serum of asymptomatic women who go on to develop spontaneous preterm labor, and to investigate the potential role for matrix metalloproteinases, their inhibitors, and collagen VI in a serum-based screening model to predict PPROM. Serum decorin level decreases less than 1% per week, and serum biglycan decreases by 2.9% per week over the duration of healthy pregnancy. Serum decorin and biglycan concentrations do not differ in spontaneous preterm labor cases compared with those in controls. Mean concentrations of MMP-2, MMP-9, TIMP-1, TIMP-2, and COL-6 do not differ in PPROM cases compared with those in controls. We have demonstrated that serum decorin and biglycan concentrations remain stable throughout the duration of normal pregnancy and are not early indicators of preterm labor, while common MMPs, TIMPs, and collagen VI are not early indicators of PPROM.

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Gálvez, Edelmira Delfina, Joaquin Bienvenido Ordieres et Salvador Fernando Capuz-Rizo. « Evaluation of Project Duration Uncertainty using the Dependency Structure Matrix and Monte Carlo Simulations ». Revista de la construcción 14, n^o 2 (août 2015) : 72–79. http://dx.doi.org/10.4067/s0718-915x2015000200010.

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Aizel, Koceila, Andrew G. Clark, Anthony Simon, Sara Geraldo, Anette Funfak, Pablo Vargas, Jérôme Bibette, Danijela Matic Vignjevic et Nicolas Bremond. « A tuneable microfluidic system for long duration chemotaxis experiments in a 3D collagen matrix ». Lab on a Chip 17, n^o 22 (2017) : 3851–61. http://dx.doi.org/10.1039/c7lc00649g.

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Fitzgerald, Jonathan B., Moonsoo Jin, Delphine Dean, David J. Wood, Ming H. Zheng et Alan J. Grodzinsky. « Mechanical Compression of Cartilage Explants Induces Multiple Time-dependent Gene Expression Patterns and Involves Intracellular Calcium and Cyclic AMP ». Journal of Biological Chemistry 279, n^o 19 (11 février 2004) : 19502–11. http://dx.doi.org/10.1074/jbc.m400437200.

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Chondrocytes are influenced by mechanical forces to remodel cartilage extracellular matrix. Previous studies have demonstrated the effects of mechanical forces on changes in biosynthesis and mRNA levels of particular extracellular matrix molecules, and have identified certain signaling pathways that may be involved. However, the broad extent and kinetics of mechano-regulation of gene transcription has not been studied in depth. We applied static compressive strains to bovine cartilage explants for periods between 1 and 24 h and measured the response of 28 genes using real time PCR. Compression time courses were also performed in the presence of an intracellular calcium chelator or an inhibitor of cyclic AMP-activated protein kinase A. Cluster analysis of the data revealed four main expression patterns: two groups containing either transiently up-regulated or duration-enhanced expression profiles could each be subdivided into genes that did or did not require intracellular calcium release and cyclic AMP-activated protein kinase A for their mechano-regulation. Transcription levels for aggrecan, type II collagen, and link protein were up-regulated ∼2–3-fold during the first 8 h of 50% compression and subsequently down-regulated to levels below that of free-swelling controls by 24 h. Transcription levels of matrix metalloproteinases-3, -9, and -13, aggrecanase-1, and the matrix protease regulator cyclooxygenase-2 increased with the duration of 50% compression 2–16-fold by 24 h. Thus, transcription of proteins involved in matrix remodeling and catabolism dominated over anabolic matrix proteins as the duration of static compression increased. Immediate early genes c-fosand c-junwere dramatically up-regulated 6–30-fold, respectively, during the first 8 h of 50% compression and remained up-regulated after 24 h.

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Calvello, M., et L. Piciullo. « Assessing the performance of regional landslide early warning models : the EDuMaP method ». Natural Hazards and Earth System Sciences 16, n^o 1 (18 janvier 2016) : 103–22. http://dx.doi.org/10.5194/nhess-16-103-2016.

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Abstract. A schematic of the components of regional early warning systems for rainfall-induced landslides is herein proposed, based on a clear distinction between warning models and warning systems. According to this framework an early warning system comprises a warning model as well as a monitoring and warning strategy, a communication strategy and an emergency plan. The paper proposes the evaluation of regional landslide warning models by means of an original approach, called the "event, duration matrix, performance" (EDuMaP) method, comprising three successive steps: identification and analysis of the events, i.e., landslide events and warning events derived from available landslides and warnings databases; definition and computation of a duration matrix, whose elements report the time associated with the occurrence of landslide events in relation to the occurrence of warning events, in their respective classes; evaluation of the early warning model performance by means of performance criteria and indicators applied to the duration matrix. During the first step the analyst identifies and classifies the landslide and warning events, according to their spatial and temporal characteristics, by means of a number of model parameters. In the second step, the analyst computes a time-based duration matrix with a number of rows and columns equal to the number of classes defined for the warning and landslide events, respectively. In the third step, the analyst computes a series of model performance indicators derived from a set of performance criteria, which need to be defined by considering, once again, the features of the warning model. The applicability, potentialities and limitations of the EDuMaP method are tested and discussed using real landslides and warning data from the municipal early warning system operating in Rio de Janeiro (Brazil).

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Volodina, Yu I., et K. A. Starikova. « Adaptive algorithm of estimating project task duration ». Bulletin of the South Ural State University. Ser. Computer Technologies, Automatic Control & ; Radioelectronics 23, n^o 1 (janvier 2023) : 67–81. http://dx.doi.org/10.14529/ctcr230106.

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The article deals with the problem of underestimation or overestimation of time required for any particular task in a company to be completed. Tasks were exported from the help desk software. The main reasons of incorrect time evaluation are determined: tasks complete time is evaluated only by the head of the company, and tasks project and employee who perform the task are not considered. Objective of the study. Increasing the accuracy of estimating task duration with considering of selected employee and task project. Materials and methods of research. A model that describes the process of setting tasks and working on tasks is developed for increasing task duration estimation. Controllable, uncontrollable external factors and internal parameters of the system are defined for the right problem definition and criteria for estimating the duration of the task is drafted. The analysis of the initial situation is carried out, the computed estimation accuracy is 1.26. 3 categories and 33 types of tasks are identified during the analysis. The experts are grouped to estimate the execution time of tasks of different types. The coefficients of each expert’s competences are calculated. An estimate of the execution time for each type of task is calculated, with considering the weight of the relevance of each expert. The conclusion that expert assessment do not fully solve the problem is made. Adaptive algorithm of estimating project task duration is proposed, which is based on the time calculated by experts, with considering the personal coefficients of employee who performs the task. A three-dimensional weighting matrix, which consider the project, the type of task, and the employee who will perform the task, is created. The corresponding matrix coefficients are regularly updated after the task is completed, which makes it possible to take into account the individual characteristics of each employee and track the time progress of performing tasks of the same type. Due to the specifics of work in the company, when calculating the coefficients, the “forgetting” parameter is introduced, which allows to increase the planned time for completing the task due to last time when employee completed task of this project. Results. The algorithm is implemented in the company help desk software. The system with the algorithm is trying to adapt to the personal characteristics of each employee and to estimate more accurately personally his time to complete any task. The suggested adaptive algorithm worked for 3 months, during which more than 2000 tasks were completed. The calculated estimation accuracy is 0.74. The improvement in accuracy is 41%. Conclusion. The algorithm and developed module for company help desk software made it possible to significantly increase the accuracy of determining the time to complete each task, the time for task evaluation is reduced to several seconds due to the possibility of evaluation by any of the employees, and the task decomposition process is improved. In the future, it is planned to add a text recognition system to automatically determine the type of task.

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Tee, Tiam Ting, Soo Tueen Bee, Tin Sin Lee, Chantara Thevy Ratnam et Haraveen Kaur Jogindar Singh. « Hot Set Characterization of Electron Beam Irradiated-Copper (II) Oxide Added LDPE Composites under Acidic Aging ». Applied Mechanics and Materials 786 (août 2015) : 63–67. http://dx.doi.org/10.4028/www.scientific.net/amm.786.63.

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In this research study, the effect of aging duration time and electron beam irradiation dosages on the hot set results of copper (II) oxide added LDPE composites have been investigated. The addition of copper (II) oxide particles in LDPE matrix has significantly reduced the formation of crosslinking networks in LDPE matrix by blocking the mobility of free radicals generated by electron beam irradiation. At lower irradiation dosages (< 100 kGy), all the copper (II) oxide added LDPE composites were immediately failed the hot set test when subjected to static load of 20 N/cm2 under high temperature. Besides, the occurrence of copper (II) oxide particles in LDPE matrix also reduced the matrix continuities of copper (II) oxide added LDPE composites and caused the matrix resistance ability of LDPE matrix to be decreased. The increasing of irradiation dosages has significantly delayed the failing time of all LDPE composites when under static load at high temperature. This is because the increasing of electron beam irradiation could further induce the generation of free radicals to form higher degree of crosslinking networks in LDPE matrix. At higher irradiation dosage up to 250 kGy, the pristine LDPE was observed able to withstand the applied static load under high temperature more than 15 minutes. This is due to higher degree of crosslinking networks formed in LDPE matrix could effectively restrict the mobility of LDPE chains under static load and thus delay the failing of sampels. When the aging duration time increased from 4 days to 14 days, the resistance ability of all LDPE has been significantly weakened due to the occurrence of chain scissioning process in LDPE matrix by delaying the failing time of samples.

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Lou, Ching Wen, Tzu Hsuan Chao, Chao Tsang Lu, Po Ching Lu et Jia Horng Lin. « Effects of Sodium Hydroxide Treatment Duration on the Physical Properties of IRM^®/Polylactic Acid Composite Filling Materials ». Applied Mechanics and Materials 365-366 (août 2013) : 999–1002. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.999.

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The purpose of this study is to explore the influence of the sodium hydroxide (NaOH) treatment duration on the physical properties of the composite filling material. This study uses Intermediate Restorative Material (IRM®) as matrix and 2 % of polylactic acid (PLA) fiber as reinforcing material to make the IRM®/PLA composite filling material. Before being infused into the IRM® matrix, the 2-mm long PLA fiber is treated by NaOH solution for 5, 10, 15, 20, 30, 60, or 90 minutes. The setting time and compressive strength of resulting composite filling materials are evaluated, determining the optimum treatment duration is 60 minutes. The compressive strength is increased by 41 %.

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Anatzki, J., et F. Gronwald. « Accelerating the numerical computation of indirect lightning effects by means of vector fitting ». Advances in Radio Science 9 (1 août 2011) : 323–28. http://dx.doi.org/10.5194/ars-9-323-2011.

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Abstract. In the context of numerical computation of indirect lightning effects it is customary to use volume-discretizing methods in time domain, such as the Finite Difference Time Domain (FDTD) method, the Finite Integration Technique (FIT), or the Transmission Line Matrix (TLM) method. If standard lightning electromagnetic pulses (LEMPs) of tenths of microseconds duration are used as excitations, these methods require long computation times, as implied by the Courant criterion. It is proposed to use shorter pulse forms and to compare the transfer functions obtained by different pulse durations by means of macromodels that are obtained from the vector fitting method. Numerical computation of lightning related transfer functions of a canonical structure indicate that the duration of the exciting pulse can typically be shortened by at least one order of magnitude if compared to a standard pulse.

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Tee, Tiam Ting, Soo Tueen Bee, Tin Sin Lee, Chantara Thevy Ratnam, Haraveen Kaur Jogindar Singh et Chong Yu Low. « Effect of Electron Beam Irradiation on Mechanical Properties of Copper (II) Oxide Added LDPE Composites Aged under Acidic Condition ». Applied Mechanics and Materials 786 (août 2015) : 13–17. http://dx.doi.org/10.4028/www.scientific.net/amm.786.13.

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In this study, the effect of aging time duration in acidic solution and electron beam irradiation on the physical and mechanical properties of copper (II) oxide added LDPE composites haven been investigated. The tensile strength of all (3 phr and 5 phr) copper (II) oxide added LDPE composites was gradually increased with increasing of electron beam irradiation dosages from 0 kGy to 200 kGy. The electron beam irradiation could induce the formation of crosslinking networks in LDPE matrix by increasing the resistance ability of LDPE matrix towards applied straining stress. The increasing of aging time duration in acidic condition up to 4 days has marginally reduced the tensile strength of all un-irradiated and irradiated all copper (II) oxide added LDPE composites. This might be attributed to the hydrochloric acid solution could degrade and breakdown the macromolecular chains in LDPE matrix and thus further reduce the tensile strength of copper (II) oxide added LDPE composites.

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Yuan, Shou, QiKun Sun, Yaguang Wang, Lingtai Yue, Jie Ma, Yuefa Zhang, Haichang Zhang, Shanfeng Xue et Wenjun Yang. « Manipulating matrix stacking modes for ultralong-duration organic room-temperature phosphorescence in trace isomer doping systems ». Journal of Materials Chemistry C 9, n^o 26 (2021) : 8302–7. http://dx.doi.org/10.1039/d1tc01744f.

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The experimental results revealed that cognate π–π stacking between matrix carbazole rings is detrimental to RTP lifetime and afterglow and that breaking such aggregations can increase RTP lifetime and enhance RTP afterglow.

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Rajendran, Harish Kumar. « Effect of Matrix Rhythm Therapy in Venous Ulcer Healing : A case report ». International Journal of Physiotherapy and Research 9, n^o 5 (11 octobre 2021) : 4040–43. http://dx.doi.org/10.16965/ijpr.2021.187.

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Introduction: Venous Ulcers are due to abnormal vein function. People may inherit a tendency for abnormal vein. Common causes of damaged veins include blood clots, injury, ageing and obesity. This is one of the common problems for professionals who are standing by nature. Symptoms include swelling, aching and tiredness in the legs. Usually a red, irritated skin rash develops into a open wound. Matrix Rhythm Therapy (MaRhyThe) is a recent clinical modality, which works on cell biology and gives good results in pain management and restriction of movements. intervention: Matrix Rhythm Therapy was applied on posterior aspect of leg region extending around the wound are once a week for 8 weeks with treatment duration of 60 minutes. Result: Pain of the subject after 8 session was 0 at rest and 2 while walking on the basis of VAS. Wound size is length 8 cm and breadth 7 cm and 2 mm dept and categorized as Type A grade 1 which completely healed with healthy scar. The photographic evidence is suggestive considerable healing of venous ulcers are noted between each session of matrix rhythm therapy (MaRhyThe). Conclusion: Study concludes that Matrix rhythm therapy (MaRhyThe) could be considered as adjunct in wound healing of venous ulcers. KEY WORDS: Matrix rhythm Therapy, Venous ulcers.

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Tekinay, Mustafa, Cory Beard et Appie van de Liefvoort. « Partial Packet Duplication : Control of Fade and Non-Fade Duration Outages Using Matrix Exponential Distributions ». IEEE Transactions on Vehicular Technology 69, n^o 5 (mai 2020) : 5652–56. http://dx.doi.org/10.1109/tvt.2020.2978848.

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Rubis, Pawel, Sylwia Wisniowska-Smialek, Ewa Wypasek, Lucyna Rudnicka-Sosin, Barbara Biernacka-Fijalkowska, Artur Kozanecki et Piotr Podolec. « EXTRACELLULAR MATRIX TURNOVER IS NOT RELATED TO THE DURATION OF THE DISEASE IN DILATED CARDIOMYOPATHY ». Journal of the American College of Cardiology 67, n^o 13 (avril 2016) : 1402. http://dx.doi.org/10.1016/s0735-1097(16)31403-6.

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Kong, Michele, Yao Li, Robert Oster, Amit Gaggar et John Paul Clancy. « High Matrix Metalloproteinase-8 and -9 Activity Predicts Duration of Mechanical Ventilation in Pediatric ARDS ». Chest 140, n^o 4 (octobre 2011) : 1052A. http://dx.doi.org/10.1378/chest.1114008.

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Kamiya, Hiroyuki, Susan Peters, Nita Sodhi-Berry, Alison Reid, Len Gordon, Nicholas de Klerk, Fraser Brims, Arthur W. Musk et Peter Franklin. « Validation of an Asbestos Job-Exposure Matrix (AsbJEM) in Australia : Exposure–Response Relationships for Malignant Mesothelioma ». Annals of Work Exposures and Health 63, n^o 7 (23 mai 2019) : 719–28. http://dx.doi.org/10.1093/annweh/wxz038.

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Abstract Objectives An asbestos job-exposure matrix (AsbJEM) has been developed to systematically and cost-effectively evaluate occupational exposures in population-based studies. The primary aim of this study was to examine the accuracy of the AsbJEM in determining exposure–response relationships between asbestos exposure estimates and malignant mesothelioma (MM) incidence (indirect validation). The secondary aim was to investigate whether the assumptions used in the development of the original AsbJEM provided accurate asbestos exposure estimates. Methods The study population consisted of participants in an annual health surveillance program, who had at least 3-month occupational asbestos exposure. Calculated asbestos exposure indices included cumulative asbestos exposure and the average exposure intensity, estimated using the AsbJEM and duration of employment. Asbestos and MM exposure–response relationships were compared between the original AsbJEM and its variations based on manipulations of the intensity, duration and frequency of exposure. Twenty-four exposure estimates were calculated for both cumulative asbestos exposure and the average exposure intensity using three exposure intensities (50th, 75th and 90th percentile of the range of mode exposure), four peak durations (15, 30, 60 and 120 min) and two patterns of peak frequency (original and doubled). Cox proportional hazards models were used to describe the associations between MM incidence and each of the cumulative and average intensity estimates. Results Data were collected from 1602 male participants. Of these, 40 developed MM during the study period. There were significant associations between MM incidence and both cumulative and average exposure intensity for all estimates. The strongest association, based on the regression-coefficient from the models, was found for the 50th percentile of mode exposure, 15-min peak duration and the doubled frequency of peak exposure. Using these assumptions, the hazard ratios for mesothelioma were 1 (reference), 1.91, 3.24 and 5.37 for the quartiles of cumulative asbestos exposure and 1 (reference), 1.84, 2.31 and 4.40 for the quartiles of the average exposure intensity, respectively. Conclusion The well-known positive exposure–response relationship between MM incidence and both estimated cumulative asbestos exposure and average exposure intensity was confirmed. The strongest relationship was found when the frequency of peak exposure in the AsbJEM was doubled from the originally published estimates.

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Huang, Ce, et Minghui Fu. « A Modified Precise Integration Method for Long-Time Duration Dynamic Analysis ». Mathematical Problems in Engineering 2018 (14 juin 2018) : 1–12. http://dx.doi.org/10.1155/2018/9646017.

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This paper presents a modified Precise Integration Method (PIM) for long-time duration dynamic analysis. The fundamental solution and loading operator matrices in the first time substep are numerically computed employing a known unconditionally stable method (referred to as original method in this paper). By using efficient recursive algorithms to evaluate these matrices in the first time-step, the same numerical results as those using the original method with small time-step are obtained. The proposed method avoids the need of matrix inversion and numerical quadrature formulae, while the particular solution obtained has the same accuracy as that of the homogeneous solution. Through setting a proper value of the time substep, satisfactory accuracy and numerical dissipation can be achieved.

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Ivaskevych, Ihor, Oleh Vanchulyak, Yurii Ushenko et Artem Motrich. « Temporal dynamics of change of polycrystalline component of bioctisses and blood of death from poisoning by alcohol and carbon with different time since death ». Forensic-medical examination, n^o 2 (25 novembre 2021) : 63–73. http://dx.doi.org/10.24061/2707-8728.2.2021.8.

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The article contains the results of a study of the effectiveness of forensic medical determination of the prescription of death by the method of differential Müller-matrix polarization-phase tomography, which is implemented by multichannel probing of rhizopolarization with laser beams of histological sections of the brain, myocardium, adrenal glands, liver and blood of the deceased and multichannel polarization filtration series images with algorithmic reproduction (reconstruction) of coordinate distributions (tomograms) of the average linear birefringence (LD) of polycrystalline networks. Aim of the work. Efficiency study by the method of differential Müller-matrix polarization-phase tomography for determining the duration of death. Materials and methods. The object of the study was the histology of samples of human internal organs (brain, myocardium, adrenal glands, and liver) with different duration of damage from 6 hours to 48 hours (we used BT samples from those who died from alcohol poisoning and carbon monoxide poisoning). For control, we used BT samples from those who died from ischemic heart disease with different duration of damage from 6 hours to 48 hours. The studies were carried out using the method of differential Muller-matrix polarization-phase tomography. Results. The range of linear change in the magnitude of the higher-order statistical moments, and accordingly the analytical determination of the DNS, lies in the range from 20 hours to 48 hours. The accuracy of determining the DNS is also significantly improved and amounts to 0.5 hours. Conclusion. The high efficiency of Muller matrix algorithmic reproduction of maps of average values of birefringence of the optically anisotropic component of biological preparations of the deceased was revealed.

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Suryadinata, Rivan Virlando, Bambang Wirjatmadi, Merryana Andriani et Sri Sumarmi. « The Expression Change of Mmp-8 and Collagen Type-2 Intracell in Lung Tissue Due to Electronic Smoke Exposure ». Jurnal Kesehatan Masyarakat 18, n^o 1 (4 août 2022) : 31–40. http://dx.doi.org/10.15294/kemas.v17i2.26557.

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The number of electronic smokers has increased annually. Exposure to an electronic cigarette will increase free radicals in the body and result in oxidative stress causing lung tissue damage. The severity degree of lung tissue damage caused by electronic smoke exposure depends on the duration of electronic cigarette smoke exposure, and will affect Matrix Metalloproteinase-8 and collagen type-2 in the cells. The study aims to understand the change degree of Matrix Metalloproteinase-8 and collagen type-2in lung tissue due to electronic cigarette smoke exposure. This study applied the experimental method with a post control group design. The male Wistar rats were used as the animal models in this research to assess cell damage through the Matrix Metalloproteinase-8 expression and collagen type-2 in the lung tissue using immunohistochemical staining. Exposure to electronic smoke cigarettes was given to each group of animal models with the difference in amount and time duration. The expression of Matrix Metalloproteinase-8 indicated a significant increase due to electronic smoke exposure (ANOVA, p=0.000). Meanwhile the expression of collagen type-2 showed a significant decrease because of electronic smoke exposure (ANOVA, p=0.000). Besides, MMP-8 and collagen type-2 manifested relationship existence and strong impact (r=0.948, p=0.000). The negative impact of exposure to electric cigarette smoke causes increased expression of Matrix Metalloproteinase-8 and decreased expression of type-2 collagen in lung tissue.

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Nikitin, Andrey, Alexander Zvekov, Alexander Kalenskii, Marina Ananeva et Denis Nurmukhametov. « Absorption profile of laser impulse of composites based on transparent matrix and metal nanoparticles ». Thermal Science 23, Suppl. 2 (2019) : 553–60. http://dx.doi.org/10.2298/tsci19s2553n.

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In this work the technique of modeling of optoacoustic signal initiated by laser pulse in composites based on transparent matrix and metal nanoparticles was proposed. It was shown that the time to achieve mechanical equilibrium is significantly lower than the pulse duration, and pressure is proportional to the augmentation of the nanoparticles? temperature. Testing of the modeling technique was carried out on the example of PETN - aluminum nanoparticles composite in two variant with and without taking into account the temperature dependence of the composites? optical properties. Comparison of calculated and experimental dependences of the effective absorption coefficient on the energy density of neodymium laser with pulse duration 14 ns was made. The modeling results are in good agreement with the experimental data only if the temperature dependence of the optical properties is taken into account.

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Ismail, Ismail, Quratul Aini, Zulkarnain Jalil, Niyi Gideon Olaiya, Mursal Mursal, C. K. Abdullah et Abdul Khalil H.P.S. « Properties Enhancement Nano Coconut Shell Filled in Packaging Plastic Waste Bionanocomposite ». Polymers 14, n^o 4 (16 février 2022) : 772. http://dx.doi.org/10.3390/polym14040772.

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Plastic waste recycling has been proposed as a long-term solution to eliminate land and marine deposit. This study proposed a new approach to fabricate biocomposites of nano-sized fillers and low matrix compositions with a great performance by using plastic packaging waste different from the conventional biocomposite. Coconut shell, an agricultural waste, was bonden with waste plastic to form a biocomposite with a coupling agent. The optimum percentage composition and the effect of coconut shell ball milling time on the properties of the biocomposite were studied with density, thickness swelling, porosity flexural strength, flexural modulus, compressive strength, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscope (SEM), and atomic force microscopy (AFM). The results showed that the optimum performance of biocomposite was obtained at 30/70 (wt.%) plastic waste to coconut shell ratio, where 70 wt.% was the highest coconut shell composition that can be achieved. Furthermore, for 30 wt.% of polypropylene (low matrix), the performance of biocomposite improved significantly with milling time due to enhanced interaction between filler and matrix. As the milling time was increased from 0 to 40 h, the density increased from 0.9 to 1.02 g/cm3; thickness swelling decreased from 3.4 to 1.8%; porosity decreased from 7.0 to 3.0%; flexural strength increased from 8.19 to 12.26 MPa; flexural modulus increased from 1.67 to 2.87 GPa, and compressive strength increased from 16.00 to 27.20 MPa. The degradation temperature of biocomposite also increased as the milling duration increased from 0 to 40 h. The melting temperature increased significantly from 160 to 170 °C as the milling duration increased from 0 to 40 h. The depolymerisation occurred at 350 °C, which also increased with milling duration. This study revealed that the performance of biocomposite improved significantly with a lower percentage matrix and fillernanoparticle rather than increasing the percentage of the matrix. The nanocomposite can be used as a panelboard in industrial applications.

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Chang, Ching-Hung, Leigh Robinson, Shih-Tung Shu et Shang-Chun Ma. « Fitness innovativeness, duration of stay, and revisit behavior : a moderation relationship ». International Journal of Sports Marketing and Sponsorship 20, n^o 4 (4 novembre 2019) : 634–45. http://dx.doi.org/10.1108/ijsms-10-2018-0107.

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Purpose Customers’ innovativeness regarding services and products affects their purchase behavior. The purpose of this paper is to examine the moderation effect of fitness innovativeness (FI) (domain-specific innovativeness) and duration of stay on fitness customers’ revisit frequency. Design/methodology/approach This is a quantitative study. The purposive sampling survey method was used to obtain samples from the Taipei Nangang Fitness Center. Data were analyzed by moderated regression analysis. Findings The empirical results from 192 valid questionnaires that were obtained for data analysis revealed that FI has a positive impact on revisit frequency, and this impact is further increased if an individual is inclined to exercise and to stay longer at the fitness center. Originality/value A matrix of fitness innovator segments was developed to illustrate the research and managerial implications.

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Andari, Fitria Nisa, Eppy Yundra, Nur Kholis, Arif Widodo et Farid Baskoro. « Analysis of IEEE 802.15.4-Based Delay and Slot Duration Adjustment Combination Methods on Wireless Sensor Networks ». INAJEEE Indonesian Journal of Electrical and Eletronics Engineering 4, n^o 2 (25 novembre 2021) : 51–58. http://dx.doi.org/10.26740/inajeee.v4n2.p51-58.

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IEEE 802.15.4 is one of the standards of the Wireless Sensor Network (WSN) which is at the Medium Access Control (MAC) layer. IEEE 802.15.4 is also technology and protocol within a computer network that can connect all device quickly, has a large capacity and low power consumption. The challenge of Wireless Sensor Network is how to improve the Wireless Sensor Network network performance matrix (goodput, bandwidth utilization, and energy consumption) both in the Contention Access Period (CAP) and in the Contention Free Period (CFP) based on the IEEE 802.15.4 standard. This research is an analysis combination of adjustment delay and slot duration methods to increase goodput, bandwidth utilization and reduce energy consumption in Wireless Sensor Networks in the allocation guaranteed time slots on fixed data simulated using Castalia Simulator software. The problem of this research is whether the combination method can improve the performance matrix of Wireless Sensor Networks on fixed data compared to other methods (SUDAS, ADES, IEEE 802.15.4 Standard). This reserch it aims to determine the performance matrix of combination methods is when compared to other methods (Superframe Duration Adjustment Scheme (SUDAS), Adjustment Delay Scheme (ADES), IEEE 802.15.4 standard) using quantitative approach research methods. Based on the data obtained, the goodput of the combined method increased by 10%, 416%, and 513% respectively compared to the SUDAS method, ADES method, and IEEE 802.15.4 standards. Bandwidth utilization of the combination methods increased by 0.025, 0.223 and 0.232, respectively compared to the SUDAS method, the ADES method, and the IEEE 802.15.4 standard. And the consumption of the combination methods are respectively reduced by 1.02%, 8.72% and 9.08% compared to the SUDAS, ADES and IEEE 802.15.4 standards. With the combination method of delay adjustment and slot duration it is able to optimize the performance of the Wireless Sensor Network compared to other methods.

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Goswami, Dinesh G., Neha Mishra, Rama Kant, Chapla Agarwal, Claire R. Croutch, Robert W. Enzenauer, Mark J. Petrash, Neera Tewari-Singh et Rajesh Agarwal. « Pathophysiology and inflammatory biomarkers of sulfur mustard-induced corneal injury in rabbits ». PLOS ONE 16, n^o 10 (12 octobre 2021) : e0258503. http://dx.doi.org/10.1371/journal.pone.0258503.

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Sulfur mustard (SM) is a cytotoxic, vesicating, chemical warfare agent, first used in 1917; corneas are particularly vulnerable to SM exposure. They may develop inflammation, ulceration, neovascularization (NV), impaired vision, and partial/complete blindness depending upon the concentration of SM, exposure duration, and bio-physiological conditions of the eyes. Comprehensive in vivo studies have established ocular structural alterations, opacity, NV, and inflammation upon short durations (<4 min) of SM exposure. In this study, detailed analyses of histopathological alterations in corneal structure, keratocytes, inflammatory cells, blood vessels, and expressions of cyclooxygenase (COX)-2, matrix metalloproteinase (MMP)-9, vascular endothelial growth factor (VEGF), and cytokines were performed in New Zealand white rabbits, in a time-dependent manner till 28 days, post longer durations (5 and 7 min) of ocular SM exposure to establish quantifiable endpoints of injury and healing. Results indicated that SM exposure led to duration-dependent increases in corneal thickness, opacity, ulceration, epithelial-stromal separation, and epithelial degradation. Significant increases in NV, keratocyte death, blood vessels, and inflammatory markers (COX-2, MMP-9, VEGF, and interleukin-8) were also observed for both exposure durations compared to the controls. Collectively, these findings would benefit in temporal delineation of mechanisms underlying SM-induced corneal toxicity and provide models for testing therapeutic interventions.

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Kumar, Deepak, ,. Archana et Abadhesh Kumar Niranjan. « A Comprehensive Review on Sustained Release Matrix Drug Delivery System ». Journal of Drug Delivery and Therapeutics 12, n^o 4-S (25 août 2022) : 249–53. http://dx.doi.org/10.22270/jddt.v12i4-s.5540.

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Formulations for sustained medication release are very useful in the treatment of chronic disorders. The oral route has selected matrix tablets as the most likely type of prolonged drug release. In order to generate therapeutic activity for a protracted duration, matrix tablets maintain a stable plasma drug concentration and sustain the rate of release of the drug throughout time. In preparations with a short half-life and high dosage frequency, extended-release is crucial. The matrix regulates how quickly the medication is released. Retardants such polyglycolic acid, polymethyl methacrylate, and hydroxypropyl methylcellulose (HPMC) are used. The retardant's matrix core contains the medication. The matrices employed can be mineral-based, hydrophobic, or biodegradable. Drug release is regulated in matrix tablets that can be made using wet granulation or direct compression techniques by the use of various kinds of polymers. Drug release from matrix tablets is controlled by both diffusion- and dissolution-controlled process. As a result, matrix tablets increase therapeutic efficacy while reducing the frequency of drug administration and increasing patient compliance. Keywords: Sustained release, Matrix Tablets, HPMC, Retardants, Biodegradable

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