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A photoswitchable organocatalyst controls trimethylene carbonate and δ-valerolactone copolymerization

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Science Bulletin 2018年第22期63卷 1460-1461页

作者： Madeline N.Riffel zachary C.Hern Paula L.Diaconescu Department of Chemistry and Biochemistry University of California

Switchable catalysts can be reversibly altered to produce two (or more)states displaying orthogonal *** use of compounds containing a "switchable"unit in ring opening polymerization (ROP)of cyclic esters and ethers has been an attractive area of research due to the biosourced and biodegradable nature of the polymers produced and enhanced control of the polymer structure. Such systems for ROP have been reported using various stimuli such as temperature [1],redox [2-6] or chemical reagents [7,8], electrodes [9],and,recently,light [10].

关键词：催化剂状态

Surgery for pancreatic cancer:recent progress and future directions

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Hepatobiliary Surgery and Nutrition 2021年第3期10卷 376-378页

作者： zachary J.Brown Jordan M.Cloyd Department of Surgery The Ohio State University Wexner Medical CenterColumbusOHUSA

Pancreatic ductal adenocarcinoma(PDAC)is a highly aggressive malignancy in which multimodality therapy is necessary to achieve good long-term *** recent seminar by Mizrahi et *** in The Lancet not only summarizes the fundamental knowledge of PDAC but also provides a concise overview of landmark studies that guide modern clinical practice(1).

关键词： Surgery al. adenocarcinoma

Household perceptions and subjective valuations of indoor residual spraying programmes to control malaria in northern Uganda

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Infectious Diseases of Poverty 2016年第1期5卷 920-932页

作者： zachary S.Brown Randall A.Kramer David Ocan Christine Oryema Department of Agricultural and Resource Economics North Carolina State UniversityRaleighNCUSA Nicholas School of the Environment Duke UniversityDurhamNCUSA Duke Global Health Institute Duke UniversityDurhamNCUSA Gulu University Gulu TownUganda

Background:Insecticide-based tools remain critical for controlling vector-borne diseases in *** public support from targeted populations for such tools is an important component in sustaining their long-run *** little quantitative evidence is available on the perceived benefits and costs of vector control programmes among targeted ***:A survey was administered to a clustered random sample of 612 households in Gulu and Oyam districts of northern Uganda during a period of very high malaria transmission and following a pilot indoor residual spray(IRS)programme.A discrete choice experiment was conducted within the survey,in which respondents indicated their preferences for different IRS programmes relative to money compensation in a series of experimentally controlled,hypothetical choice *** data were analysed using conditional logit regression models to estimate respondents’willingness to accept(WTA)some amount of money compensation in lieu of foregone malaria risk *** class models were used to analyse whether respondent characteristics predicted ***:Average WTA is estimated at$8.94 annually for a 10%reduction in malaria risk,and additional co-benefits of IRS were estimated to be worth on average$54–$56(depending on insecticide type)per round of *** heterogeneity is observed:Four in five household heads in northern Uganda have high valuations for IRS programmes,while the remaining 20%experience costly side effects of IRS(valued at between$2 and$3 per round).Statistically significant predictors of belonging to the high-value group include respondent gender,mean age of household members,participation in previous IRS,basic knowledge of mosquito reproduction,and the number of mosquito nets *** for household income and wealth are not found to be statistically significant predictors of ***:This study suggests that the majority of people in areas of high malaria transmission

关键词： annually programme income

The effects of a bike active video game on players' physical activity and motivation

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Journal of Sport and Health Science 2017年第1期6卷 25-32,127页

作者： Denis Pasco Cédric Roure Gilles Kermarrec zachary Pope Zan Gao School of Education The University of Bourgogne Franche-ComtéBesançon 25000France Faculty of Movement Sciences The Catholic University of LouvainLouvain-La-Neuve B-1348Belgium Faculty of Sport Science and Education The University of Brittany-LoireBrest 29200France School of Kinesiology The University of MinnesotaMinneapolisMN 55455USA

Background: Players may not acquire adequate levels of moderate-to-vigorous physical activity(MVPA) when playing commercial video *** study's goal was to evaluate the effects of an exercise bike video game played by using a mobile application-based exergame that was designed exclusively to promote participants' MVPA, with additional attention paid to this game's ability to promote greater situational ***: An experimental design was used with 163 students(aged 20.31 ± 1.30, 18–26 years, 61.3% male), all of whom were randomly allocated into an experimental group and a control group. Physical activity(PA) levels were assessed with Acti Graph GT3X+(Acti Graph Inc., Fort Walton Beach, FL, USA) accelerometers. The situational interest scale was used to evaluate students' situational interest in both *** analysis of variance was conducted to examine the differences between sedentary behavior, PA levels, and situational interest between groups. Regression analyses were also used, with the purpose being to evaluate the strength of the relationship between PA and situational ***: Results revealed that the experimental group had higher degrees of sedentary behavior, light PA, total interest, instant enjoyment,exploration intention, attention demand, novelty, and challenge, whereas the control group received higher scores for MVPA(control 95.01% *** group 89.94%). Regression analysis indicated that instant enjoyment(β = 0.49, p < 0.01), exploration intention(β = 0.18, p < 0.05),and attention demand(β = 0.17, p < 0.05) were positive predictors for total interest, explaining 43% of its ***: A newly designed mobile application-based exergame played via an exercise bike may enhance situational interest and provide a decent level of PA for players.

关键词： Design Exergame Moderate-to-vigorous physical activity Sedentary behavior Situational interest Young adults

Stability, variation, and application of AFIS fiber length distributions

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Journal of Cotton Research 2020年第2期3卷 79-89页

作者： HINDS zachary KELLY Brendan Robert HEQUET Eric Francois Texas Tech University 2500 BroadwayLubbockTX 79409USA Texas AgriLife Research 1102 E Farm to Market Rd 1294LubbockTX 79403USA

Background:Fiber length is one of the primary quality parameters for the cotton industry when considering the textile performance and end-use quality of ***,many decisions regarding cotton fiber length utilize the industry standard measurement device,i.e.,the High Volume Instrument(HVI).However,it is documented that complete fiber length distributions hold more information than the currently reported HVI length parameters,i.e.,upper half mean length(UHML)and uniformity index(UI).An alternative measurement device,the Advanced Fiber Information System(AFIS),is able to capture additional information about fiber length *** is currently not known is how much additional information the AFIS length distribution ***:The stability of differences in within-sample variation in fiber length captured by the AFIS length distribution by number characterizing differences between samples was deemed stable across the extended testing period.A diverse breeding population was evaluated and four significant sources of within sample variation in length were identified.A comparison of the ability between HVI length parameters and AFIS fiber length distribution to correctly categorize breeding lines to their family was *** all cases,the AFIS fiber length distribution more accurately identified germplasm ***:The long-term stability test of the AFIS fiber length distribution by number shows that the measurement is stable and can be used to assess differences across ***,more information about within-sample variation in fiber length than that can be captured by length parameters is needed to assess differences across samples in many *** length parameters outperform two length parameters when trying to identify the familial background of the samples in this *** parameters characterize distributional shape differences that are not captured by the standard AFIS length parameters,UQL and short fiber cont

关键词： Cotton Fiber quality Fiber length distribution Advanced Fiber information system(AFIS)

Silica-coating-assisted nitridation of TiO_(2) nanoparticles and their photothermal property

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Nano Research 2021年第9期14卷 3228-3233页

作者： Qilin Wei Danielle L.Kuhn zachary Zander Brendan G.DeLacy Hai-Lung Dai Yugang Sun Department of Chemistry Temple University1901 North 13th StreetPhiladelphiaPennsylvania 19122USA U.S.Army Edgewood Chemical Biological Center Research&Technology DirectorateAberdeen Proving GroundMaryland 21010USA

Nanoparticles of refractory compounds represent a class of stable materials showing a great promise to support localized surface plasmon resonances(LSPRs)in both visible and near infrared(NIR)spectral *** is still challenging to rationally tune the LSPR band because of the difficulty to control the density of charge carriers in individual refractory nanoparticles and maintain the dispersity of nanoparticles in the processes of synthesis and *** this work,controlled chemical transformation of titanium dioxide(TiO_(2))nanoparticles encapsulated with mesoporous silica(SiO_(2))shells to titanium nitride(TiN)via nitridation reaction at elevated temperatures is developed to tune the density of free electrons in the resulting titanium-oxide-nitride(TiO_(x)N_(y))*** tunability enables a flexibility to support LSPR-based optical absorption in the synthesized TiO_(x)N_(y)@SiO_(2) core-shell nanoparticles across both the visible and NIR *** silica shells play a crucial role in preventing the sintering of TiO_(x)N_(y) nanoparticles in the nitridation reaction and maintaining the stability of TiOxNy nanoparticles in *** LSPR-based broadband absorption of light in the TiO_(x)N_(y)@SiO_(2) nanoparticles exhibits strong photothermal effect with photo-to-thermal conversion efficiency as high as〜76%.

关键词： titanium-oxide-nitride nanoparticles mesoporous silica coating nitridation reaction structural transformation plasmonic absorption photothermal effect

Nature-inspired chiral metasurfaces for circular polarization detection and full-Stokes polarimetric measurements

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Light(Science & Applications) 2019年第1期8卷 494-504页

作者： Ali Basiri Xiahui Chen Jing Bai Pouya Amrollahi Joe Carpenter zachary Holman Chao Wang Yu Yao School of Electrical Computer and Energy EngineeringArizona State UniversityTempeAZ 85281USA Centre for Photonic Innovation Arizona State UniversityTempeAZ 85281USA Biodesign Centre for Molecular Design&Biomimetics Arizona State UniversityTempeAZ 85281USA

The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and *** metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation,manipulation,and ***,we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion *** experimentally demonstrated submicron-thick circularly polarized light filters with peak extinction ratios up to 35 and maximum transmission efficiencies close to 80% at near-infrared wavelengths(the best operational wavelengths can be engineered in the range of 1.3-1.6μm).We also monolithically integrated the microscale circular polarization filters with linear polarization filters to perform full-Stokes polarimetric measurements of light with arbitrary polarization *** the advantages of easy on-chip integration,ultracompact footprints,scalability,and broad wavelength coverage,our designs hold great promise for facilitating chip-integrated polarimeters and polarimetric imaging systems for quantum-based optical computing and information processing,circular dichroism spectroscopy,biomedical diagnosis,and remote sensing applications.

关键词： polarization circular polar

Hypoxia-inducing cryogels uncover key cancer-immune cell interactions in an oxygen-deficient tumor microenvironment

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Bioactive Materials 2023年第11期29卷 279-295页

作者： Thibault Colombani zachary JRogers Khushbu Bhatt James Sinoimeri Lauren Gerbereux Mohammad Hamrangsekachaee Sidi ABencherif Department of Chemical Engineering Northeastern UniversityBostonMA 02115United States Department of Pharmaceutical Sciences Northeastern UniversityBostonMAUnited States Department of Bioengineering Northeastern UniversityBostonMA 02115United States Harvard John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA 02138United States Biomechanics and Bioengineering(BMBI) UTC CNRS UMR 7338University of Technology of Compi`egneSorbonne University60203 Compi`egneFrance

Hypoxia is a major factor shaping the immune landscape,and several cancer models have been developed to emulate hypoxic ***,to date,they still have several limitations,such as the lack of reproducibility,inadequate biophysical cues,limited immune cell infiltration,and poor oxygen(O_(2))control,leading to non-pathophysiological tumor ***,it is essential to develop better cancer models that mimic key features of the tumor extracellular matrix and recreate tumor-associated hypoxia while allowing cell infiltration and cancer-immune cell ***,hypoxia-inducing cryogels(HICs)have been engineered using hyaluronic acid(HA)to fabricate three-dimensional microtissues and model a hypoxic tumor ***,tumor cell-laden HICs have been designed to deplete O_(2) locally and induce long-standing *** promoted changes in hypoxia-responsive gene expression and phenotype,a metabolic adaptation to anaerobic glycolysis,and chemotherapy ***,HIC-supported tumor models induced dendritic cell(DC)inhibition,revealing a phenotypic change in the plasmacytoid DC(pDC)subset and an impaired conventional DC(cDC)response in ***,our HIC-based melanoma model induced CD8^(+)T cell inhibition,a condition associated with the downregulation of pro-inflammatory cytokine secretion,increased expression of immunomodulatory factors,and decreased degranulation and cytotoxic capacity of T ***,these data suggest that HICs can be used as a tool to model solid-like tumor microenvironments and has great potential to deepen our understanding of cancer-immune cell relationship in low O_(2) conditions and may pave the way for developing more effective therapies.

关键词： Cryogels Hypoxia Cancer Immunosuppression Drug resistance

Effects of exergaming on motor skill competence,perceived competence,and physical activity in preschool children

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Journal of Sport and Health Science 2019年第2期8卷 106-113页

作者： Zan Gao Nan Zeng zachary C.Pope Ru Wang Fang Yu School of Kinesiology University of Minnesota-Twin Cities Department of Food Science and Human Nutrition Colorado State University School of Public Health University of Minnesota-Twin Cities School of Kinesiology Key Laboratory of Exercise and Health Sciences of Ministry of Education Shanghai University of Sport School of Nursing University of Minnesota-Twin Cities

Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outcomes in this age group. This study's purpose, therefore, was to examine a school-based exergaming intervention's effect on preschool children's perceived competence(PC), motor skill competence(MSC), and physical activity versus usual care(recess), as well as to examine gender differences for these ***: A total of 65 preschool children from 2 underserved urban schools were assigned to 1 of 2 conditions, with the school as the experimental unit:(1) usual care recess group(8 weeks of 100 min of recess/week(5 days ￡ 20 min)) and(2) exergaming intervention group(8 weeks of100 min of exergaming/week(5 days ￡ 20 min) at school). All children underwent identical assessments of PC, MSC, and moderate-to-vigorous physical activity(MVPA) at baseline and at the end of the 8 th ***: A significant Group ￡ Time effect was observed for MVPA, F(1, 52) = 4.37, p = 0.04, h2 p= 0.04, but not for PC, F(1, 52) = 0.83, p = 0.37,h2 p= 0.02, or MSC, F(1, 52) = 0.02, p = 0.88, h2 p= 0.00. Specifically, the intervention children displayed significantly greater increased MVPA after8 weeks than the comparison children. Additionally, there was a significant time effect for MSC, F(1, 52) = 15.61, p < 0.01, h2 p= 0.23, and gender effect for MVPA, F(1, 52) = 5.06, p = 0.02, h2 p= 0.09. Although all preschoolers' MSC improved across time, boys demonstrated greater MVPA than girls at both time ***: Exergaming showed a positive effect in promoting preschool children's MVPA at school and has the potential to enhance PC and MSC. More research with larger sample sizes and longer study durations are warranted.

关键词： Active video games Childhood obesity Gender differences Moderate-to-vigorous physical activity Recess