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A core-shell composite pigment with rutile TiO_(2) intensification for UV inhibition

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Particuology 2022年第8期20卷 18-26页

作者： Xiao Lv Baowei Yan Yuanyuan Shao Haiping Zhang Hui Zhang jesse Zhu Cllaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTionjin UniversityTianjin 300350China Department of Chemical and Biochemical Engineering.Western Universiy Ontario N6A 589Canada

Organic pigments generlly have bright colors but poor ultraviolet(UV)*** improve the UV for UVinhibition is proposed by afacile sol-gel method inthis ***-shellstructure,witha homo resistance and extend the applications,a core-shell composite pigment with rutile Tio intensification geneous sol-gel TiO_(2) shell containing additional nanosized rutile TiO2 particles and with the pigment as the core,was established taking advantage of UV resistance of TiO2 and binding ability of *** the sol-gel TiO2 shell alone has already shown obvious ultraviolet shielding effect,as tested over different sol-gel aging times and Tio2 loadings,the UV resistance of the fluorescent pigments was further enhanced by binding the nanosized rutile TiO2 in the sol-gel shell At a sol-gel TiO2 to rutile TiO2 ratio of 2:1,the UV exposure time is extended about eight times compared with that of the original pigment and twice as that of the modifed pigment with pure sol-gel TiO2 for the same color ***,the novel core-shell composite pigment intensified with nanosized rutile Tio2 particles is proved to be effcient in improving the uV resistance of organic pigments.

关键词： Sol-gel RutileTiO_(2) Organic pigment Core-shell UV resistance Powder coating

Estimating effective reproduction number using generation time versus serial interval,with application to COVID-19 in the Greater Toronto Area,Canada

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Infectious Disease Modelling 2020年第1期5卷 889-896页

作者： jesse Knight Sharmistha Mishra Institute of Medical Science University of TorontoCanada MAP Centre for Urban Health Solutions Unity Health TorontoCanada Division of Infectious Disease Department of MedicineUniversity of TorontoCanada Institute of Health Policy Management and EvaluationDalla Lana School of Public HealthUniversity of TorontoCanada

*** effective reproduction number Re(t)is a critical measure of epidemic ***(t)can be calculated in near real time using an incidence time series and the generation time distribution:the time between infection events in an infector-infectee *** calculating Re(t),the generation time distribution is often approximated by the serial interval distribution:the time between symptom onset in an infector-infectee ***,while generation time must be positive by definition,serial interval can be negative if transmission can occur before symptoms,such as in COVID-19,rendering such an approximation improper in some *** developed a method to infer the generation time distribution from parametric definitions of the serial interval and incubation period *** then compared estimates of Re(t)for COVID-19 in the Greater Toronto Area of Canada using:negative-permitting versus non-negative serial interval distributions,versus the inferred generation time *** estimated the generation time of COVID-19 to be Gamma-distributed with mean 3.99 and standard deviation 2.96 *** to the generation time distribution,non-negative serial interval distribution caused overestimation of Re(t)due to larger mean,while negative-permitting serial interval distribution caused underestimation of Re(t)due to larger *** of the generation time distribution of COVID-19 with non-negative or negative-permitting serial interval distributions when calculating Re(t)may result in over or underestimation of transmission potential,respectively.

关键词： Reproduction number Generation time Serial interval Incubation period COVID-19

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脑胶质瘤细胞顺铂耐药分子标志物筛选

中国神经肿瘤杂志 2009年第3期7卷 167-170页

作者：崔磊付军吴浩强彭颂先陈忠平华南肿瘤学国家重点实验室中山大学肿瘤防治中心神经外科/神经肿瘤科广东广州510060 香港中文大学解剖病理系及细胞学系

背景与目的:顺铂是神经肿瘤化疗常用药物之一,耐药是疗效不佳原因之一。遗传学改变可以影响肿瘤细胞对化疗的敏感性。本研究旨在利用芯片-基因组杂交技术筛选胶质瘤细胞中与顺铂耐药相关的分子标志物。方法:用芯片-基因组杂交技术对我... 详细信息

背景与目的:顺铂是神经肿瘤化疗常用药物之一,耐药是疗效不佳原因之一。遗传学改变可以影响肿瘤细胞对化疗的敏感性。本研究旨在利用芯片-基因组杂交技术筛选胶质瘤细胞中与顺铂耐药相关的分子标志物。方法:用芯片-基因组杂交技术对我们先前采用顺铂剂量梯度爬升诱导的对顺铂高度耐药的U251/CP2细胞(IC50为76.5μg/mL)和亲代细胞U251细胞(IC50为1.2μg/ml)筛选与顺铂耐药相关的分子标志物。RT-PCR和实时荧光定量PCR用来对结果进行验证。结果:补体因子H相关蛋白1基因(CFHR1)和补体因子H相关蛋白3基因(CFHR3)在U251细胞中至少各自缺失了一个拷贝,在U251/CP2细胞中完全缺失。IL-7基因在U251/CP2细胞中的拷贝数为U251细胞的2～3倍。结论:CFHR1、CFHR3和IL-7基因可能与胶质瘤对顺铂耐药有关。

关键词：脑肿瘤胶质瘤顺铂耐药芯片-基因组杂交

Anti-bat tiger moth sounds:Form and function

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Current Zoology 2010年第3期56卷 358-369页

作者： Aaron J.CORCORAN William E.CONNER jesse R.BARBER Department of Biology Wake Forest University Department of Fish Wildlife and Conservation BiologyColorado State University

The night sky is the venue of an ancient acoustic battle between echolocating bats and their insect prey. Many tiger moths （Lepidoptera： Arctiidae） answer the attack calls of bats with a barrage of high frequency clicks. Some moth species use these clicks for acoustic aposematism and mimicry, and others for sonar jamming, however, most of the work on these defensive functions has been done on individual moth species. We here analyze the diversity of structure in tiger moth sounds liom 26 spe- cies collected at three locations in North and South America. A principal components analysis of the anti-bat tiger moth sounds reveals that they vary markedly along three axes：（1） frequency, （2） duty cycle （sound production per unit time） and frequency modulation, and （3） modulation cycle （clicks produced during flexion and relaxation of the sound producing tymbal） structure. Tiger moth species appear to cluster into two distinct groups： one with low duty cycle and few clicks per modulation cycle that supports an acoustic aposematism function, and a second with high duty cycle and many clicks per modulation cycle that is con- sistent with a sonar jamming function. This is the first evidence from a community-level analysis to support multiple functions for tiger moth sounds. We also provide evidence supporting an evolutionary history for the development of these strategies. Further- more, cross-correlation and spectrogram correlation measurements failed to support a ＂phantom echo＂ mechanism underlying sonar jamming, and instead point towards echo interference [Current Zoology 56 （3）： 358-369, 2010].

关键词： Acoustic aposematism Sonar jamming Arctiidae Cross-correlation Autocorrelation

Plasmonic mode mixing in nanoparticle dimers with nm-separations via substrate-mediated coupling

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Nano Research 2014年第9期7卷 1344-1354页

作者： jesse Theiss Mehmet Aykol Prathamesh Pavaskar Stephen B. Cronin Ming Hsieh Department of Electrical Engineering University of Southern California Los Angeles CA 90089 USA

We fabricate arrays of metallic nanoparticle dimers with nanometer separation using electron beam lithography and angle evaporation. These ＂nanogap＂ dimers are fabricated on thin silicon nitride membranes to enable high resolution transmission electron microscope imaging of the specific nanoparticle geometries. Plasmonic resonances of the pairs are characterized by dark-field scattering micro-spectroscopy, which enables the optical scattering from individual nano- structures to be measured by using a spatially-filtered light source to illuminate a small area. Scattering spectra from individual dimers are correlated with transmis- sion electron microscope images and finite-difference time-domain simulations of their electromagnetic response, with excellent agreement between simulation and experiment. We observe a strong polarization dependence with two dominant scattering peaks in spectra taken with the polarization aligned along the dimer axis. This response arises from a unique Fano interference, in which the bright hybridized modes of an asymmetric dimer are able to couple to the dark higher- order hybridized modes through substrate-mediated coupling. The presence of this interference is strongly dependent on the nanoparticle geometry that defines the plasmon energy profile but also on the intense localization of charge at the dielectric surface in the nanogap region for separations smaller than 6 nm.

关键词： plasmonics fano interference transmission electron microscopy (TEM) nanogapdark-field spectroscopy

Acoustic emission characterization of microcracking in laboratory-scale hydraulic fracturing tests

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第5期10卷 805-817页

作者： jesse Hampton Marte Gutierrez Luis Matzar Dandan Hu Luke Frash Department of Civil & Environmental Engineering Colorado School of Mines Golden CO 80401 USA New England Research Inc. White River Junction VT 03766 USA Halliburton Houston TX 77032 USA Los Alamos National Laboratory Los Alamos NM 87545 USA

Understanding microcracking near coalesced fracture generation is critically important for hydrocarbon and geothermal reservoir characterization as well as damage evaluation in civil engineering structures. Dense and sometimes random microcracking near coalesced fracture formation alters the mechanical properties of the nearby virgin material. Individual microcrack characterization is also significant in quantifying the material changes near the fracture faces （i.e. damage）. Acoustic emission （AE） monitoring and analysis provide unique information regarding the microcracking process temporally, and infor- mation concerning the source characterization of individual microcracks can be extracted. In this context, laboratory hydraulic fracture tests were carried out while monitoring the AEs from several piezoelectric transducers. In-depth post-processing of the AE event data was performed for the purpose of under- standing the individual source mechanisms. Several source characterization techniques including moment tensor inversion, event parametric analysis, and volumetric deformation analysis were adopted. Post-test fracture characterization through coring, slicing and micro-computed tomographic imaging was performed to determine the coalesced fracture location and structure. Distinct differences in fracture characteristics were found spatially in relation to the openhole injection interval. Individual microcrack AE analysis showed substantial energy reduction emanating spatially from the injection interval. It was quantitatively observed that the recorded AE signals provided sufficient information to generalize the damage radiating spatially away from the injection wellbore.

关键词： Acoustic emission (AE) Microcracking Hydraulic fracturing Laboratory-scale testing Moment tensor analysis Fracture coalescence Computed tomography (CT) imaging

Putting the brakes on chloroplast stress signaling

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Molecular Plant 2022年第3期15卷 388-390页

作者： David W.Tano jesse D.Woodson The School of Plant Sciences University of Arizona303 Forbes Hall1140 E.South Campus DriveTucsonAZUSA

As sessile organisms,plants must be able to sense their surroundings and *** way plants do this is by using their energy-producing organelles(chloroplasts and mitochondria).During environmental stress,these organelles experience metabolic changes that induce signals for *** many metabolites have been proposed as signaling factors,reactive oxygen species(ROS)are known to play prominent *** the chloroplast,the ROS singlet oxygen(^(1)O_(2))is naturally produced during impaired photosynthesis and can lead to retrograde signaling to the nucleus(to control the expression of hundreds of genes),chloroplast degradation,and cell death.

关键词： organelle stress hundreds

A Characterization for Dominant Strategy Implementation

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2013年第1期8卷 1-18页

作者： jesse A. Schwartz Quan Wen Department of Economics Finance and Quantitative Analysis Kennesaw State UniversityKennesaw GA 30144 USA Department of Economics Vanderbilt University Nashville TN 37235-1819 USA

We introduce a perfect price discriminating mechanism for allocation prob- lems with private information. A perfect price discriminating mechanism treats a seller, for example, as a perfect price discriminating monopolist who faces a price schedule that does not depend on her report. In any perfect price discriminating mechanism, every player has a dominant strategy to truthfully report her private infor- mation. We establish a characterization for dominant strategy implementation： Any outcome that can be dominant strategy implemented can also be dominant strategy implemented using a perfect price discriminating mechanism. We apply this charac- terization to derive the optimal, budget-balanced, dominant strategy mechanisms for public good provision and bilateral bargaining.

关键词： perfect price discriminating (PPD) dominant strategy implementation,Vickrey-Clarke-Groves mechanisms public good provision bilateral bargaining

Long-term landscape changes in a subalpine spruce-fir forest in central Utah, USA

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Forest Ecosystems 2016年第2期3卷 83-94页

作者： jesse L.Morris R.Justin DeRose Andrea R.Brunelle Department of Forest Rangeland and Fire Sciences College of Natural Resources University of Idaho Moscow ID 83844 USA USDA Forest Service Forest Inventory Analysis Rocky Mountain Research Station Ogden UT 84401 USA. Department of Geography University of Utah Salt Lake City UT 84112 USA

Background： In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change. Understanding the relationship among climate, antecedent disturbances, and the legacy effects of settlement-era logging can help identify the patterns and processes that create landscapes susceptible to bark beetle epidemics. Methods： Our analysis uses data from lake sediment cores, stand inventories, and historical records. Sediment cores were dated with radiometric techniques （14C and 210pb/137Cs） and subsampled for pollen and charcoal to maximize the temporal resolution during the historical period （1800 CE to present） and to provide environmental baseline data （last 10,500 years）. Pollen data for spruce were calibrated to carbon biomass （C t/ha） using standard allometric equations and a transfer function. Charcoal samples were analyzed with statistical models to facilitate peak detection and determine fire recurrence intervals. Results： The Wasatch Plateau has been dominated by Engelmann spruce forests for the last ～10,500 years, with subalpine fir becoming more prominent since 6000 years ago. This landscape has experienced a dynamic fire regime, where burning events are more frequent and of higher magnitude during the last 3000 years. Two important disturbances have impacted Engelmann spruce in the historical period： 1） high-grade logging during the late 19th century; and （2） a high severity spruce beetle outbreak in the late 20th century that killed 〉90 % of mature spruce （〉10 cm dbh）. Conclusions： Our study shows that spruce-dominated forests in this region are resilient to a range of climate and disturbance regimes. Several lines of evidence suggest that 19th century logging promoted a legacy o

关键词： Spruce beetle Climate change Dendroctonus Engelmann spruce Logging Western North America Wildfire