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A kinetic model for horizontal transfer and bacterial antibiotic resistance

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International Journal of Biomathematics 2017年第4期10卷 131-151页

作者： Damian A. Knopoff juan M. sanchez Sanso Centro de Investigacion y Estudios de Matemdtica CONICET -- FaMAF Universidad Nacional de Cordoba Medina AUende s/n Cordoba 5000 Argentina Department of General Surgery Hospital Misericordia Nuevo Siglo Cordoba 5000 Argentina

This paper presents a mathematical model for bacterial growth, mutations, horizontal transfer and development of antibiotic resistance. The model is based on the so-called kinetic theory for active particles that is able to capture the main complexity features of the system. Bacterial and immune cells are viewed as active particles whose microscopic state is described by a scalar variable. Particles interact among them and the temporal evolution of the system is described by a generalized distribution function over the microscopic state. The model is derived and tested in a couple of case studies in order to confirm its ability to describe one of the most fundamental problems of modern medicine, namely bacterial resistance to antibiotics.

关键词： Kinetic theory active particles antibiotic resistance horizontal gene transfer

Detecting accidental punctures and lacerations during cholecystectomy in large datasets: Two methods of analysis

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 430-436页

作者： Artem Shmelev Anne M Sill Gopal C Kowdley juan A sanchez Steven C Cunningham Department of Surgery Saint Agnes Hospital and Cancer Center

Background: After the Institute of Medicine(IOM) report To Err Is Human highlighted the impact of medical errors, the Agency for Healthcare Research and Quality(AHRQ) developed Patient-Safety Indicators(PSI) to improve quality by identifying potential inpatient safety problems. PSI-15 was created to study accidental punctures and lacerations(APL), but PSI-15 may underestimate APLs in populations of patients. This study compares PSI-15 with a more inclusive approach using a novel composite of secondary diagnostic and procedural codes. Methods: We used Nationwide Inpatient Sample(NIS) data(20 0 0–2012) from AHRQ’s Healthcare Cost and Utilization Project(H-CUP). We analyzed PSI-15-positive and-negative cholecystectomies. Cross tabulations identified codes that were significantly more frequent among PSI-15-positive cases; these secondary diagnostic and procedural codes were selected as candidate members of a composite marker(CM) of APL. We chose cholecystectomy patients for study because this is one of the most common general operations, and the large size of NIS allows for meaningful analysis of infrequent occurrences such as APL rates. Results: CM identified 1.13 times more APLs than did PSI-15. Patients with CM-detected APLs were significantly older and had worse mortality, comorbidities, lengths of stay, and charges than those detected with PSI-15. Further comparison of these two approaches revealed that time-series analysis for both APL markers revealed parallel trends, with inflections in 2007, and lowest APL rates in July. Conclusions: Although CM may yield more false positives, it appears more inclusive, identifying more clinically significant APLs, than PSI-15. Both measures presented similar trends over time, arguing against inflation in PSI-15 reporting. While arguably less specific, CM may increase sensitivity for detecting APL events during cholecystectomies. These results may inform the interpretation of other large population studies of APLs following abd

关键词： Cholecystectomy Patient safety Accidental lacerations AHRQ PSI-15

Perspectives on the role of Pannexin 1 in neural precursor cell biology

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Neural Regeneration Research 2016年第10期11卷 1540-1544页

作者： juan C.sanchez-Arias Leigh E.Wicki-Stordeur Leigh Anne Swayne Division of Medical Sciences University of Victoria Island Medical Program and Department of Cellular and Physiological Sciences University of British Columbia

We recently reported that targeted deletion of Pannexin 1 in neural precursor cells of the ventricular zone impairs the maintenance of these cells in healthy and stroke-injured brain. Here we frame this exciting new finding in the context of our previous studies on Pannexin 1 in neural precursors as well as the close rela- tionship between Pannexin 1 and purinergic receptors established by other groups. Moreover, we identify important gaps in our understanding of Pannexin 1 in neural precursor cell biology in terms of the under- lying molecular mechanisms and functional/behavioural outcomes.

关键词： neural precursor ventricular zone pannexin ATP cytoskeleton proliferation phagoptosis

Growth performance,gastrointestinal weight,microbial metabolites and apparent retention of components in broiler chickens fed up to 11%rice bran in a corn-soybean meal diet without or with a multi-enzyme supplement

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Animal Nutrition 2019年第1期5卷 41-48页

作者： juan sanchez Aizwarya Thanabalan Tanka Khanal Rob Patterson Bogdan A.Slominski Elijah Kiarie Department of Animal Biosciences University of Guelph Canadian Bio-Systems Inc. Department of Animal Science University of Manitoba

We investigated the effects of adding up to 11% rice bran(RB) in corn-soybean meal diets fed to broiler chickens without or with a multi-enzyme supplement(MES). The MES supplied xylanase, b-glucanase invertase, protease, cellulase, a-amylase and mannanase with targeted activity of 2,500, 300, 700, 10,0001,200, 24,000, and 20 U/kg of feed, respectively. The study used a two-phase feeding program(starter d 0 to 24; finisher, d 25 to 35) with RB added at 5% and 11%, respectively creating 4 diets in each phase Diets were iso-caloric and iso-nitrogenous and contained phytase(500 FTU/kg) and TiO_2 as a digestibility marker. Three hundred and sixty d-old male Ross 708 broiler chicks were placed in cages based on BW(15 birds/cage) and allocated to 4 diets(n = 6). Birds had free access to feed and water. Body weight and feed intake were recorded. Excreta samples were collected 3 d prior to the end of each phase for apparent retention(AR) of components. Samples of birds were sacrificed on d 24 and 35 for gut weight and ceca digesta for organic acid content. There was no interaction(P > 0.10) between RB and MES on BWG and FCR in starter or finisher phase. In finisher phase, birds fed MES had better BWG(961 versus 858 g) and FCR(1.69 versus 1.86) than birds fed non-MES diets(P < 0.01). Feeding RB reduced(P = 0.02) BWG in finisher phase resulting in lower d 35 BW. Birds fed RB had higher(P 0.01) gizzard weight on d 24 and 35 than non-RB birds. An interaction(P 0.01) between RB and MES on concentrations of propionic and iso-butyric acids in ceca digesta showed that MES reduced these acids in non-RB diet. The AR of gross energy was higher(P < 0.02) for MES versus non-MES birds in starter and finisher phases. In conclusion independently, RB increased gizzard weight and reduced final BW whereas MES improved growth and energy utilization.

关键词： Broiler chickens Growth performance Gut weight Microbial activity Multi-enzyme supplement Rice bran

Gastrointestinal stromal tumors:a multidisciplinary challenge

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World Journal of Gastroenterology 2018年第18期24卷 1925-1941页

作者： juan Manuel sanchez-Hidalgo Manuel Duran-Martinez Rafael Molero-Payan Sebastian Rufian-Pena Alvaro Arjona-sanchez Angela Casado-Adam Antonio Cosano-Alvarez Javier Briceno-Delgado Department of General and Digestive Surgery Reina Sofia University HospitalAvda.Menéndez Pidal s/nCordoba 14004Spain Department of Intern Medicine Reina Sofia University HospitalAvda.Menéndez Pidal s/nCordoba 14004Spain Lipids and Atherosclerosis Research Unit IMIBIC/Hospital Universitario Reina Sofía/Universidad de CórdobaCordoba 14004Spain

Gastrointestinal stromal tumors(GISTs) are the most common mesenchymal tumors located in the alimentary tract. Its usual manifestation is gastrointestinal bleeding. However, small asymptomatic lesions are frequently detected as incidental finding. Characteristically, most GISTs(> 95%) are positive for the KIT protein(CD117) by IHC staining and approximately 80%-90% of GISTs carry a mutation in the c-KIT or PDGFRA genes. Mutational analysis should be performed when planning adjuvant and neoadjuvant therapy, due to its possible resistance to conventional treatment. The arise of tyrosine kinase inhibitor has supposed a revolution in GISTs treatment being useful as adjuvant, neoadjuvant or recurrence disease treatment. That is why a multidisciplinary approach to this disease is required. The correct characterization of the tumor at diagnosis(the diagnosis of recurrences and the evaluation of the response to treatment with tyrosine kinase inhibitors) is fundamental for facing these tumors and requires specialized Endoscopist, Radiologists and Nuclear Medicine Physician. Surgery is the only potentially curative treatment for suspected resectable GIST. In the case of high risk GISTs, surgery plus adjuvantImatinib-Mesylate for 3 years is the standard treatment. Neoadjuvant imatinib-mesylate should be considered to shrink the tumor in case of locally advanced primary or recurrence disease, unresectable or potentially resectable metastasic tumors, and potentially resectable disease in complex anatomic locations to decrease the related morbidity. In the case of Metastatic GIST under Neoadjuvant treatment, when there are complete response, stable disease or limited disease progression, complete cytoreductive surgery could be a therapeutic option if feasible.

关键词： Gastrointestinal stromal tumors Surgery Oncology Radiology Endoscopy Nuclear medicine Pathology Disease management Tyrosine kinase inhibitors Gastroenterology

基于多时相TanDEM-X极化干涉SAR数据的水稻株高反演

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光谱学与光谱分析 2020年第3期40卷 878-884页

作者：国贤玉李坤邵芸 juan MLopez-sanchez 王志勇山东科技大学测绘科学与工程学院山东青岛266590 中国科学院遥感与数字地球研究所北京100101 中国科学院大学资源与环境学院北京100049 中科卫星应用德清研究院微波目标特性测量与遥感重点实验室浙江德清313200 University of Alicante Alicante99Spain

水稻株高是水稻本身以及土壤、水文、气象等因素的综合反映,是水稻长势监测的重要指标。准确、高效、大范围的株高反演为水稻品种识别、物候监测、病虫害评估和产量预测等提供了可靠的依据。合成孔径雷达(SAR),具有全天时、全天候、穿... 详细信息

水稻株高是水稻本身以及土壤、水文、气象等因素的综合反映,是水稻长势监测的重要指标。准确、高效、大范围的株高反演为水稻品种识别、物候监测、病虫害评估和产量预测等提供了可靠的依据。合成孔径雷达(SAR),具有全天时、全天候、穿透性的优势,成为水稻株高反演的重要手段之一。基于极化干涉测量(PolInSAR)的散射模型的反演算法具有严密的物理模型的支撑及较高的反演精度等特点,成为植被高度反演研究的热点。结合极化干涉SAR技术,构建了一种基于RVoG(Random Volume over Ground)模型的水稻株高反演算法,并利用2015年水稻生长季内9个时相的TanDEM-X极化干涉SAR数据,进行了水稻株高反演试验。首先基于每个时相下的极化干涉SAR数据分别得到8个复相干系数,利用这8个复相干系数在考虑卫星双站模式等情况下进行去相干处理,然后建立适用于水稻田特性的RVoG模型,接着构建基于该模型的水稻株高反演迭代算法,最后对9个时相下的TanDEM-X数据进行研究区的水稻株高反演及精度评定。结果表明,当水稻株高高于0.4m时,该方法的反演结果较好,决定系数(R^2)为0.86,均方根误差RMSE为6.79 cm;当水稻株高较低时(水稻株高小于0.4 m),反演误差在0.1~0.8 m之间,反演结果较差,被明显高估。通过分析认为,基于极化干涉理论,TanDEM-X数据在较好地反映出水稻植株的较大体散射量的前提下,利用所构建的基于RVOG模型的水稻株高反演算法,能够较好地反演株高在0.33~1.2 m的水稻株高。

关键词：水稻株高 TanDEM-X 极化干涉SAR RVoG模型模式搜索法

Growth factors and fetal lung development mediated by mechanical forces

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World Journal of Respirology 2013年第3期3卷 44-47页

作者： juan sanchez-Esteban Department of Pediatrics Alpert Medical School Brown University

Incomplete development of the lung secondary to extreme prematurity or pulmonary hypoplasia causes significant morbidity and mortality during the neonatal period. Currently, the management is primarily supportive with no specific treatment to stimulate the growth and development of the lung. Mechanical forces generated inside the fetal lung by constant distention pressure and "breathing-like movements" are a major determinant of fetal lung development. However, the mechanisms by which lung cells sense these mechanical signals to promote lung development are not well-defined. Tracheal ligation has been used not only experimentally but also in human fetuses affected by severe congenital diaphragmatic hernia to stimulate lung growth and decrease the degree of pulmonary hypoplasia. Past investigations suggested that the increase of intratracheal pressure after tracheal ligation releases soluble factors that are critical for lung development. Studies from our laboratory have shown that mechanical strain of fetal type Ⅱ epithelial cells, simulating mechanical forces in utero, promotes differentiation via release of epidermal growth factor receptor ligands heparin binding epidermal growth factor-like growth factor and transforming growth factor alpha. The identification of growth factors released by mechanical forces that are importantfor normal lung development could lead to novel treatments to accelerate lung development.

关键词： Mechanical forces Lung development Tracheal ligation Growth factors

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Journal of Ancient Civilizations 2011年第1期26卷 103-105页

作者： juan Pablo sanchez

Dr. Raoul McLaughlin （http：//***/） studied Archaeology and Ancient History at Queen＇s University Belfast, where he is currently Tutor. His research fields include Roman commerce, the ancient economy and contacts between Rome and the Distant East. This monograph is based on the author＇s Phd dissertation on Rome＇s eastern trade completed in 2006. Besides this book, McLaughlin has also published some magazine and newspaper articles on this topic.

关键词：古代历史博士论文电子商务考古学罗马

Electronic structure, optical properties, and lattice dynamics in atomically thin indium selenide flakes

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Nano Research 2014年第10期7卷 1556-1568页

作者： juan F. sanchez-Royo Suillermo Munoz-Matutano Mauro Brotons-Gisbert juan P. Martinez-Pastor Alfredo Segura Andres Cantarero Rafael Mata Josep Canet-Ferrer Gerard Tobias Enric Canadell Jose Marques-Hueso Brian D. Gerardot ICMUV Instituto de Oencia de Materiales Universidad de Valencia P.O. Box 22085 46071 Valencia Spain MALTA-Consolider Team Institut de Ciencia dels Materials-Dpto. de Fisica Apficada Universitat de Valencia E-46100 Burjassot (Valencia) Spain Institut de Ciencia de Materials de Barcelona (ICMAB-CSIC) Campus de la UAB 08193 Bellaterra Barcelona Spain Institute of Photonics and Quantum Science SUPA Hefiot-Watt University Edinburgh EH14 4AS UK

The progressive stacking of chalcogenide single layers gives rise to two- dimensional semiconducting materials with tunable properties that can be exploited for new field-effect transistors and photonic devices. Yet the properties of some members of the chalcogenide family remain unexplored. Indium selenide （InSe） is attractive for applications due to its direct bandgap in the near infrared, controllable p- and n-type doping and high chemical stability. Here, we reveal the lattice dynamics, optical and electronic properties of atomically thin InSe flakes prepared by micromechanical cleavage. Raman active modes stiffen or soften in the flakes depending on which electronic bonds are excited. A progressive blue-shift of the photoluminescence peaks is observed for decreasing flake thickness （as large as 0.2 eV for three single layers）. First-principles calculations predict an even larger increase in the bandgap, 0.40 eV, for three single layers, and as much as 1.1 eV for a single layer. These results are promising from the point of view of the versatility of this material for optoelectronic applications at the nanometer scale and compatible with Si and III-V technologies.

关键词： indium selenide two-dimensional flakes micro-Raman spectroscopy micro-photoluminescence electronic structure