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Identification of Ca2+ signaling components in neural stem/progenitor cells during differentiation into neurons and glia in intact and dissociated zebrafish neurospheres

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Science China(life Sciences) 2018年第11期61卷 1352-1368页

作者： Man Kit Tse Ting Shing Hung Ching Man Chan Tiffany Wong Mike Dorothea Catherine leclerc Marc Moreau Andrew l.Miller sarah E.Webb Division of life Science & State Key laboratory of Molecular Neuroscience HKUSTClear Water BayHongKongChina Centre de Biologie du Developpement(CBD) Centre de Biologie Integrative(CBI)Universite de ToulouseCNRSUPSToulouse F-31062France

The development of the CNS in vertebrate embryos involves the generation of different sub-types of neurons and glia in a complex but highly-ordered spatio-temporal manner. Zebrafish are commonly used for exploring the development, plasticity and regeneration of the CNS, and the recent development of reliable protocols for isolating and culturing neural stem/progenitor cells(NSCs/NPCs) from the brain of adult fish now enables the exploration of mechanisms underlying the induction/specification/differentiation of these cells. Here, we refined a protocol to generate proliferating and differentiating neurospheres from the entire brain of adult zebrafish. We demonstrated via RT-qPCR that some isoforms of ip3 r, ryr and stim are upregulated/downregulated significantly in differentiating neurospheres, and via immunolabelling that 1,4,5-inositol trisphosphate receptor(IP3 R) type-1 and ryanodine receptor(RyR) type-2 are differentially expressed in cells with neuron-or radial glial-like properties. Furthermore, ATP but not caffeine(IP3 R and RyR agonists, respectively), induced the generation of Ca^(2+) transients in cells exhibiting neuron-or glial-like morphology. These results indicate the differential expression of components of the Ca^(2+) -signaling toolkit in proliferating and differentiating cells. Thus, given the complexity of the intact vertebrate brain, neurospheres might be a useful system for exploring neurodegenerative disease diagnosis protocols and drug development using Ca^(2+) signaling as a read-out.

关键词： Ca^2+ signaling neurospheres zebrafish neural stem/progenitor cells differentiation IP3receptors ryanodine receptors STIM and Orai

Sugarcane bagasse amendment mitigates nutrient leaching from a mineral soil under tropical conditions

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Pedosphere 2022年第6期32卷 876-883页

作者： Nan XU Jehangir H.BHADHA Abul RABBANY Stewart SWANSON James MMCCRAY Yuncong lI sarah lSTRAUSS Rao MYlAVARAPU Horticultural Sciences Department University of FloridaGainesville FL 32611(USA) Everglades Research and Education Center University of FloridaBelle Glade FL 33430(USA) Department of Soil Waterand Ecosystem SciencesUniversity of FloridaGainesville FL 32611(USA) Institute of Food and Agricultural Sciences(IFAS)Extension University of FloridaLaBelle FL 33935(USA) Agronomy Department University of FloridaBelle Glade FL 33430(USA) Department of Soil Waterand Ecosystem SciencesUniversity of FloridaHomestead FL 33031(USA) Department of Soil Waterand Ecosystem SciencesUniversity of FloridaImmokalee FL 34142(USA)

large quantities of organic by-products are generated by the sugarcane industry during sugar extraction *** by-products may be used as soil amendments to improve soil quality,as nutrient leaching is common in mineral soils of Florida in USA due to their sandy texture and frequent rain events.A soil column study was designed to evaluate the effects of bagasse application at 85 t ha^(-1) of fresh bagasse,170 t ha^(-1) of fresh bagasse,and 170 t ha^(-1) of fresh bagasse+nitrogen(N)on the leaching potential of carbon(C),N,phosphorus(P),and potassium(K).Bagasse was incorporated within the topsoil(0-15 cm)in outdoor soil columns exposed to natural conditions,with periodical irrigation during the *** approximately 57 weeks,the distributions of C,N,P,and K were evaluated at three soil depths(i.e.,0-15,15-30,and 30-53 cm)within the soil *** organic C(TOC),N,and P in leachates decreased significantly from the soils amended with bagasse compared with the control with no bagasse and no *** on K content changes in the columns,bagasse could also be utilized as a potential source of K for ***,application of bagasse as a soil amendment might be an effective way to sustainably reutilize organic by-products while reducing concerns regarding major nutrients entering groundwater *** results of this study could assist in developing nutrient management plans of using sugarcane bagasse as a potential soil amendment in mineral soils.

关键词： nutrient leaching potential nutrient loss pore volume sandy soil soil amendment soil column sugarcane by-product

High production of butyric acid by Clostridium tyrobutyricum mutant

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Frontiers of Chemical Science and Engineering 2015年第3期9卷 369-375页

作者： Chao Ma Jianfa Ou Matthew Miller sarah McFann Xiaoguang (Margaret) liu Department of Chemical and Biological Engineering The University of Alabama 245 7th Avenue Tuscaloosa AL 35401 USA

The objective of this study was to improve the production of butyric acid by process optimization using the metabolically engineered mutant of Clostridium tyrobutyricum （PAK-Em）. First, the free-cell fermentation at pH 6.0 produced butyric acid with concentration of 38.44 g/l and yield of 0.42 g/g. Second, the immobilized- cell fermentations using fibrous-bed bioreactor （FBB） were run at pHs of 5.0, 5.5, 6.0, 6.5 and 7.0 to optimize fermentation process and improve the butyric acid production. It was found that the highest titer of butyric acid, 63.02g/l, was achieved at pH 6.5. Finally, the metabolic flux balance analysis was performed to inves- tigate the carbon rebalance in C. tyrobutyricum. The results show both gene manipulation and fermentation pH change redistribute carbon between biomass, acetic acid and butyric acid. This study demonstrated that high butyric acid production could be obtained by integrating metabolic engineering and fermentation process optimization.

关键词： Clostridium tyrobutyricum butyric acid production fermentation mutant pH flux balance analysis

A review of sustainability metrics for the construction and operation of airport and roadway infrastructure

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Frontiers of Engineering Management 2019年第3期6卷 433-452页

作者： sarah M.l.HUBBARD Bryan HUBBARD School of Aviation and Transportation Technology Purdue UniversityWest LafayetteIN 47907USA School of Building Construction Management Technology Purdue UniversityWest LafayetteIN 47907USA

Sustainability has become increasingly important,however,relatively little attention has focused on metrics for the construction and operation of airport and roadway *** attention has focused on buildings,with high profile BREEAM and lEED projects taking center *** is also important in airport and roadway infrastructure projects,which have significant public impact but have a much lower profile than vertical construction when it comes to *** infrastructure is important in China and India where new infrastructure is under construction to meet growing and developing economies,and in the US,where infrastructure is in substandard condition and requires *** purpose of this paper is to provide an overview and discussion of sustainability rating systems for airport and roadway infrastructure,including both construction and *** projects that highlight both proven and innovative sustainable practices are included to illustrate the application of these ***,the relationship between sustainable transportation infrastructure and resilient transportation infrastructure is addressed since resiliency is of growing interest and there is overlap between these concepts.

关键词： sustainable construction infrastructure airport roadway resiliency sustainability

Neural Networks on an FPGA and Hardware-Friendly Activation Functions

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Journal of Computer and Communications 2020年第12期8卷 251-277页

作者： Jiong Si sarah l. Harris Evangelos Yfantis University of Nevada Las Vegas USA

This paper describes our implementation of several neural networks built on a field programmable gate array (FPGA) and used to recognize a handwritten digit dataset—the Modified National Institute of Standards and Technology (MNIST) database. We also propose a novel hardware-friendly activation function called the dynamic Rectifid linear Unit (RelU)—D-RelU function that achieves higher performance than traditional activation functions at no cost to accuracy. We built a 2-layer online training multilayer perceptron (MlP) neural network on an FPGA with varying data width. Reducing the data width from 8 to 4 bits only reduces prediction accuracy by 11%, but the FPGA area decreases by 41%. Compared to networks that use the sigmoid functions, our proposed D-RelU function uses 24% - 41% less area with no loss to prediction accuracy. Further reducing the data width of the 3-layer networks from 8 to 4 bits, the prediction accuracies only decrease by 3% - 5%, with area being reduced by 9% - 28%. Moreover, FPGA solutions have 29 times faster execution time, even despite running at a 60× lower clock rate. Thus, FPGA implementations of neural networks offer a high-performance, low power alternative to traditional software methods, and our novel D-RelU activation function offers additional improvements to performance and power saving.

关键词： Deep learning D-RelU Dynamic RelU FPGA Hardware Acceleration Activation Function

landscape distribution of food and nesting sites affect larval diet and nest size, but not abundance of Osmia bicornis

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Insect Science 2016年第5期23卷 746-753页

作者： Valerie Coudrain sarah Rittiner Felix Herzog Willy Tinner Martin H. Entling Research Station ART Zurich CH-8046 Switzerland Institute of Ecology and Evolution University of Bern Bern CH-3012 Switzerland Institute for Environmental Sciences University of Koblenz-Landau LandaulPfalz D-76829 Germany Institute of Plant Sciences and Oeschger Centre for Climate Change Research University of Bern Bern CH-3013 Switzerland

Habitat fragmentation is a major threat for beneficial organisms and the ecosys- tem services they provide. Multiple-habitat users such as wild bees depend on both nesting and foraging habitat. Thus, they may be affected by the fragmentation of at least two habitat types. We investigated the effects of landscape-scale amount of and patch isolation from both nesting habitat （woody plants） and foraging habitat （specific pollen sources） on the abundance and diet of Osmia bicornis l. Trap-nests of O. bicornis were studied in 30 agricultural landscapes of the Swiss Plateau. Nesting and foraging habitats were mapped in a radius of 500 m around the sites. Pollen composition of larval diet changed as isolation to the main pollen source, Ranunculus, increased, suggesting that （9. bicornis adapted its foraging strategy in function of the nest proximity to main pollen sources. Abundance of O. bicornis was neither related to isolation or amount of nesting habitat nor to isolation or abundance of food plants. Surprisingly, nests ofO. bicornis contained fewer larvae in sites at forest edge compared to isolated sites, possibly due to higher parasitism risk. This study indicates that O. bicornis can nest in a variety of situations by compensating scarcity of its main larval food by exploiting alternative food sources.

关键词： diet fragmentation habitat amount habitat isolation Hymenoptera Megachilidae pollen analysis

Survey of Staphylococcus aureus in a general pediatric population and focus on isolates with three clinically relevant toxin-encoding genes

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World Journal of Pediatrics 2018年第1期14卷 35-43页

作者： Anne Filleron sarah Beauregard-Birba Thibault Mura Fabien Aujoulat Anne laure Michon Michel Rodière Tu Anh Tran Eric Jeziorski Hélène Marchandin Department of Pediatrics Nimes University HospitalNimesFrance INSERM U1183 Team3Immune Regulationand Micr obiotaMedical University of Montpellier NimesNimesFrance laboratory ofBacter iology Montpellier University HospitalMontpellierFrance Department of Medical Information Montpellier UniversityHospitalMontpellierFrance Montpellier University UMR5569HydroSciencesMontpellierPharmacy University of MontpellierMontpellierFrance Division of Pediatric Infectious Diseases Departmentof P ediatricsMontpellier University HospitalMontpellierFrance Department of Micr obiology Nimes University HospitalNimesFrance

Background In children, surveys on Staphylococcus aureus have focused on specific infections, situations or strains but no study has so far given an overview on S. aureus isolation without any selection. Here, we describe the overall bacteriologi-cal and clinical characteristics of S. aureus isolation in children, with a special focus on isolates harbouringtst,sea, and/or luk-PV genes, respectively, encoding the three clinically relevant toxins: toxic shock syndrome toxin-1, enterotoxin A and Panton–Valentine leukocidin. Methods Data associated with S. aureus isolation were reviewed: isolation site, infection status,tst,sea andluk-PV genes, antimicrobial susceptibility pattern,agr typing. Results Three hundred and seventy-seven isolates retrieved from 328 children during S. aureus infection (55.2%) or colo-nisation (44.8%) were ***,sea and luk-PV genes were amplified in 14.3, 9.5 and 5.8% of the isolates, respectively. These isolates were significantly more frequently retrieved during infection (69.1%) than colonisation but differences were observed according to isolation site. Methicillin-resistance was found in 7.2% of the isolates, 78% of which harboured ≥ 1 of the targeted toxin-encoding genes. Conclusions This first comprehensive study of S. aureus in children showed S. aureus to be mainly retrieved during infection and a high rate of colonisation, not limited to the nasopharynx. Predominant infections were skin and soft tissue infections wheretst was most frequently ***-PV was most commonly detected during bone and joint infections. Isolates harbouring targeted toxin-encoding genes were significantly associated with infections but a quarter of children were asymp-tomatic carriers representing a reservoir for dissemination of isolates with virulence potency.

关键词： Colonisation Infection Pediatric Staphylococcus aureus Toxins

Influence of ellagic acid on prostate cancer cell proliferation:A caspase-dependent pathway

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Asian Pacific Journal of Tropical Medicine 2011年第7期4卷 550-555页

作者： Arshi Malik sarah Afaq Mohammad Shahid Kafil Akhtar Abdullah Assiri Department of Clinical Biochemistry College of MedicineKing Khalid UniversityAbhaKingdom of Saudi Arabia Department of Microbiology Jawaharlal Nehru Medical CollegeAligarh Muslim UniversityAligarhIndia Department of Pathology Jawaharlal Nehru Medical CollegeAligarh Muslim UniversityAligarhIndia Interventional Cardiologist College of MedicineKing Khalid UniversityAbhaKingdom of Saudi Arabia

Objective:To evaluate the effect of allagic acid treatment on the cell viability of human prostate cancer ***:Ellagic acid(10-100 mol/l) treatment(48 h) of human prostate carcinoma PC3 cells was found to result in a dose-dependent inhibition of cell growth and apoptosis of PC3 cells as assessed by MTT assay,western *** cytometry and confocal ***:We observed that ellagic acid treatment of PC3 cells resulted in a dose dependent inhibition of cell growth/cell *** ellagic acid caused cell growth inhibition was found to be accompanied by induction of apoptosis,as assessed by the cleavage of poly (ADP-ribose) polymerase(PARP) and morphological ***,induction of apoptosis accompanied a decrease in the levels of antiapoptotic protein Bcl-2 and increase in proapoptotic protein *** shifting the Bax:Bcl-2 ratio in favor of *** acid treatment of PC3 cells was also found to result in significant activation of caspases,as shown by the dose dependent decrease in the protein expression of procaspase-3,-6.-8 and -*** ellagic acid-mediated induction of apoptosis was significantly(80%-90%) inhibited by the caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone(Z-VAD-FMK).Thus these data suggested an essential role of caspases in ellagic acid-mediated apoptosis of PC3 ***:It is tempting to suggest that consumption of tropical pigmented fruits and vegetables could be an effective strategy to combat prostate cancer.

关键词： Ellagic acid Apoptosis Prostate cancer Caspases

The Early-Middle Pleistocene Transition： characterization and proposed guide for the defining boundary

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Episodes 2008年第2期31卷 255-259页

作者： Martin J. Head Brad Pillans sarah A. Farquhar Department of Earth Sciences Brock University St Catharines Ontario L2S 3A1 Canada. Research School of Earth Sciences The Australian National University Canberra ACT 0200 Australia. Cambridge Quaternary Department of Geography University of Cambridge Downing Place Cambridge CB2 3EN United Kingdom.

The mid-Pleistocene transition （MPT, c. 1.2 to 0.5 Ma） records fundamental changes in Earth＇s climate state, where low-amplitude 41-kyr obliquity-dominated cycles gave way progressively to the high-amplitude, quasiperiodic （c. 100-kyr） fluctuations that characterize the later Pleistocene and Holocene. We use wavelet analysis on the lR04 δ^l8O benthic foraminiferal stack to confirm low-frequency power as early as 1.25-1.20 Ma, determine the persistence of obliquity-dominated cyclicity through and beyond the MPT, and reveal new levels of complexity in climate evolution.

关键词：地球气候状态洪积世振幅