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排序方式: 共有2591条查询结果,搜索用时 15 毫秒
1.
Cristian Podesta Natalie Coleman Amir Esmalian Faxi Yuan Ali Mostafavi 《Journal of the Royal Society Interface》2021,18(177)
This research establishes a methodological framework for quantifying community resilience based on fluctuations in a population''s activity during a natural disaster. Visits to points-of-interests (POIs) over time serve as a proxy for activities to capture the combined effects of perturbations in lifestyles, the built environment and the status of business. This study used digital trace data related to unique visits to POIs in the Houston metropolitan area during Hurricane Harvey in 2017. Resilience metrics in the form of systemic impact, duration of impact, and general resilience (GR) values were examined for the region along with their spatial distributions. The results show that certain categories, such as religious organizations and building material and supplies dealers had better resilience metrics—low systemic impact, short duration of impact, and high GR. Other categories such as medical facilities and entertainment had worse resilience metrics—high systemic impact, long duration of impact and low GR. Spatial analyses revealed that areas in the community with lower levels of resilience metrics also experienced extensive flooding. This insight demonstrates the validity of the approach proposed in this study for quantifying and analysing data for community resilience patterns using digital trace/location-intelligence data related to population activities. While this study focused on the Houston metropolitan area and only analysed one natural hazard, the same approach could be applied to other communities and disaster contexts. Such resilience metrics bring valuable insight into prioritizing resource allocation in the recovery process. 相似文献
2.
Coleman Thomas F. Dumont Nicole S. Li Wanqi Liu Wenbin Rubtsov Alexey 《Computational Economics》2022,60(3):1101-1134
Computational Economics - The climate change model of Daniel et al. (Proc Natl Acad Sci USA 116(42):20886-20891, 2019. https://doi.org/10.1073/pnas.1817444116) is an important contribution to the... 相似文献
3.
Discovery of 5′′‐Chloro‐N‐[(5,6‐dimethoxypyridin‐2‐yl)methyl]‐2,2′:5′,3′′‐terpyridine‐3′‐carboxamide (MK‐1064): A Selective Orexin 2 Receptor Antagonist (2‐SORA) for the Treatment of Insomnia 下载免费PDF全文
Dr. Anthony J. Roecker Swati P. Mercer John D. Schreier Dr. Christopher D. Cox Dr. Mark E. Fraley Justin T. Steen Wei Lemaire Joseph G. Bruno C. Meacham Harrell Susan L. Garson Dr. Anthony L. Gotter Steven V. Fox Joanne Stevens Dr. Pamela L. Tannenbaum Dr. Thomayant Prueksaritanont Dr. Tamara D. Cabalu Dr. Donghui Cui Joyce Stellabott Dr. George D. Hartman Dr. Steven D. Young Dr. Christopher J. Winrow Dr. John J. Renger Dr. Paul J. Coleman 《ChemMedChem》2014,9(2):311-322
The field of small‐molecule orexin antagonist research has evolved rapidly in the last 15 years from the discovery of the orexin peptides to clinical proof‐of‐concept for the treatment of insomnia. Clinical programs have focused on the development of antagonists that reversibly block the action of endogenous peptides at both the orexin 1 and orexin 2 receptors (OX1R and OX2R), termed dual orexin receptor antagonists (DORAs), affording late‐stage development candidates including Merck’s suvorexant (new drug application filed 2012). Full characterization of the pharmacology associated with antagonism of either OX1R or OX2R alone has been hampered by the dearth of suitable subtype‐selective, orally bioavailable ligands. Herein, we report the development of a selective orexin 2 antagonist (2‐SORA) series to afford a potent, orally bioavailable 2‐SORA ligand. Several challenging medicinal chemistry issues were identified and overcome during the development of these 2,5‐disubstituted nicotinamides, including reversible CYP inhibition, physiochemical properties, P‐glycoprotein efflux and bioactivation. This article highlights structural modifications the team utilized to drive compound design, as well as in vivo characterization of our 2‐SORA clinical candidate, 5′′‐chloro‐N‐[(5,6‐dimethoxypyridin‐2‐yl)methyl]‐2,2′:5′,3′′‐terpyridine‐3′‐carboxamide (MK‐1064), in mouse, rat, dog, and rhesus sleep models. 相似文献
4.
Fate of physical,chemical, and microbial contaminants in domestic wastewater following treatment by small constructed wetlands 总被引:12,自引:0,他引:12
Hench KR Bissonnette GK Sexstone AJ Coleman JG Garbutt K Skousen JG 《Water research》2003,37(4):921-927
In order to evaluate the efficacy of constructed wetlands for treatment of domestic wastewater for small communities located in rural areas, small-scale wetland mesocosms (400 L each) containing two treatment designs (a mixture of Typha, Scirpus, and Juncus species; control without vegetation) were planted into two depths (45 or 60 cm) with pea gravel. Each mesocosm received 19 L/day of primary-treated domestic sewage. Mesocosms were monitored (inflow and outflow samples) on a monthly basis over a 2-year period for pH, total suspended solids (TSS), 5-day biochemical oxygen demand (BOD(5)), total Kjeldahl nitrogen (TKN), dissolved oxygen (DO), and conductivity. Microbiological analyses included enumeration of fecal coliforms, enterococci, Salmonella, Shigella, Yersinia, and coliphage. Significant differences between influent and effluent water quality for the vegetated wetlands (p<0.05) were observed in TSS, BOD(5), and TKN. Increased DO and reduction in fecal coliform, enterococcus, Salmonella, Shigella, Yersinia, and coliphage populations also were observed in vegetated wetlands. Greatest microbial reductions were observed in the planted mesocosms compared to those lacking vegetation. Despite marked reduction of several contaminants, wetland-treated effluents did not consistently meet final discharge limits for receiving bodies of water. Removal efficiencies for bacteria and several chemical parameters were more apparent during the initial year compared to the second year of operation, suggesting concern for long-term efficiency and stability of such wetlands. 相似文献
5.
Effects of an ozone-generating air purifier on indoor secondary particles in three residential dwellings 总被引:1,自引:0,他引:1
The use of indoor ozone generators as air purifiers has steadily increased over the past decade. Many ozone generators are marketed to consumers for their ability to eliminate odors and microbial agents and to improve health. In addition to the harmful effects of ozone, recent studies have shown that heterogeneous and homogeneous reactions between ozone and some unsaturated hydrocarbons can be an important source of indoor secondary pollutants, including free radicals, carbonyls, carboxylic acids, and fine particles. Experiments were conducted in one apartment and two detached single-family dwellings in Austin, TX, to assess the effects of an ozone generator on indoor secondary organic aerosol concentrations in actual residential settings. Ozone was generated using a commercial ozone generator marketed as an air purifier, and particle measurements were recorded before, during, and after the release of terpenes from a pine oil-based cleaning product. Particle number concentration, ozone concentration, and air exchange rate were measured during each experiment. Particle number and mass concentrations increased when both terpenes and ozone were present at elevated levels. Experimental results indicate that ozone generators in the presence of terpene sources facilitate the growth of indoor fine particles in residential indoor atmospheres. Human exposure to secondary organic particles can be reduced by minimizing the intentional release of ozone, particularly in the presence of terpene sources. PRACTICAL IMPLICATIONS: Past studies have shown that ozone-initiated indoor chemistry can lead to elevated concentrations of fine particulate matter, but have generally been completed in controlled laboratory environments and office buildings. We explored the effects of an explicit ozone generator marketed as an air purifier on the formation of secondary organic aerosol mass in actual residential indoor settings. Results indicate significant increases in number and mass concentrations for particles <0.7 microns in diameter, particularly when an ozone generator is used in the presence of a terpene source such as a pine oil-based cleaner. These results add evidence to the potentially harmful effects of ozone generation in residential environments. 相似文献
6.
Cover Picture: Discovery of MK‐8970: An Acetal Carbonate Prodrug of Raltegravir with Enhanced Colonic Absorption (ChemMedChem 2/2015) 下载免费PDF全文
Dr. Abbas M. Walji Dr. Rosa I. Sanchez Dr. Sophie‐Dorothee Clas Dr. Rebecca Nofsinger Dr. Manuel de Lera Ruiz Dr. Jing Li Dr. Amrithraj Bennet Christopher John Dr. David Jonathan Bennett Dr. John M. Sanders Christina N. Di Marco Somang Hope Kim Dr. Jaume Balsells Scott S. Ceglia Dr. Qun Dang Kimberly Manser Becky Nissley Dr. John S. Wai Dr. Michael Hafey Junying Wang Gene Chessen Dr. Allen Templeton Dr. John Higgins Dr. Ronald Smith Dr. Yunhui Wu Dr. Jay Grobler Dr. Paul J. Coleman 《ChemMedChem》2015,10(2):213-213
7.
M. Kopp D. Coleman C. Stiller K. Scheffer J. Aichinger B. Scheppat 《International Journal of Hydrogen Energy》2017,42(19):13311-13320
The following paper is an analysis of the operating experiences during the initial phase of the 6 MW PEM electrolysis project “Energiepark Mainz”. The paper is divided into a technical and an economic evaluation. The technical evaluation contains the calculation of the efficiency of the Power-to-Gas plant based on the total power consumption, as well as the energy utilization factor. The economic evaluation analyses the different options of electricity procurement for the electrolysis. The three options, electricity purchase at the European power exchange, excess electricity from a direct marketing company, and participating in the control reserve market have been analysed. One first outcome shows, that economic feasibility can mainly be improved through participation in the secondary control reserve market. 相似文献
8.
Kate J. Norris Andrew J. Lohn Takehiro Onishi Elane Coleman Vernon Wong Ali Shakouri Gary S. Tompa Nobuhiko P. Kobayashi 《Journal of Electronic Materials》2012,41(5):971-976
We report the growth of erbium monoantimonide (ErSb) thin films on indium antimonide (100) substrates by low-pressure metalorganic
chemical vapor deposition. The growth rate of ErSb thin films shows strong dependency on the growth temperature and the Sb/Er
precursor molar flow rate ratio. Scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffractometry
(XRD) were employed to study the ErSb thin films grown under the growth conditions that gave the maximum growth rate in the
range we investigated. We also report the growth of two types of nanocomposites in which ErSb nanocolumns or nanoslabs with
lengths ~500 nm and diameters 20 nm to 30 nm are embedded in Zn-doped InGaSb (ErSb/InGaSb:Zn) and ErSb nanoparticles with
diameters of ~30 nm are embedded in Zn-doped InSbAs (ErSb/InSbAs:Zn). These nanocomposites were intended to increase phonon
scattering in a mid-to-long phonon wavelength range to reduce lattice thermal conductivity. We used time-domain thermoreflectance
to measure total thermal conductivity for the two types of nanocomposites, obtaining 4.0 ± 0.6 W/mK and 6.7 ± 0.8 W/mK for
the ErSb/InAsSb:Zn and ErSb/InGaSb:Zn nanocomposites, respectively, which suggests that the thermal conductivity was close
to or slightly smaller than the alloy limit of the two ternary alloy hosts. The two nanocomposites were further studied by
transmission electron microscopy (TEM) to reveal their microscopic features and by XRD to assess their crystalline structures. 相似文献
9.
Fiona M. Blighe Karen Young Juan J. Vilatela Alan H. Windle Ian A. Kinloch Libo Deng Robert J. Young Jonathan N. Coleman 《Advanced functional materials》2011,21(2):364-371
We have measured the mechanical properties of coagulation‐spun polymer–nanotube composite fibers. Both the fiber modulus, Y, and strength, σB, scale linearly with volume fraction, Vf, up to Vf ~10%, after which these properties remain constant. We measured dY/dVf = 254 GPa and dσB/dVf = 2.8 GPa in the linear region. By drawing fibers with Vf < 10% to a draw ratio of ~60%, we can increase these values to dY/dVf = 600 GPa and dσB/dVf = 7 GPa. Raman measurements show the Herman's orientation parameter, S, to increase with drawing, indicating that significant nanotube alignment occurs. Raman spectroscopy also shows that the nanotube effective modulus, YEff, also increases with drawing. We have calculated an empirical relationship between the nanotube orientation efficiency factor, ηo, and S. This allows us to fit the data for YEff versus ηo, showing that the fiber modulus scales linearly with ηo, as predicted theoretically by Krenchel. From the fit, we estimate the nanotube modulus to be; YNT = 480 GPa. Finally, we show that the fiber strength also scales linearly with ηo, giving an effective interfacial stress transfer of τ = 40 MPa and a nanotube critical length of lc=1250 nm. This work demonstrates the validity of the Cox‐Krenchel rule of mixtures and shows that continuum theory still applies at the near‐molecular level. 相似文献
10.
Insulator‐Conductor Type Transitions in Graphene‐Modified Silver Nanowire Networks: A Route to Inexpensive Transparent Conductors 下载免费PDF全文
Izabela Jurewicz Azin Fahimi Phillip E. Lyons Ronan J. Smith Maria Cann Matthew L. Large Mingwen Tian Jonathan N. Coleman Alan B. Dalton 《Advanced functional materials》2014,24(48):7580-7587
Silver nanowire coatings are an attractive alternative to indium tin oxide for producing transparent conductors. To fabricate coatings with low sheet resistance required for touchscreen displays, a multi‐layer network of silver nanowires must be produced that may not be cost effective. This problem is counteracted here by modifying the electrical properties of an ultra‐low‐density nanowire network through local deposition of conducting graphene platelets. Unlike other solution‐processed materials, such as graphene oxide, our pristine graphene is free of oxygen functional groups, resulting in it being electrically conducting without the need for further chemical treatment. Graphene adsorption at inter‐wire junctions as well as graphene connecting adjacent wires contributes to a marked enhancement in electrical properties. Using our approach, the amount of nanowires needed to produce viable transparent electrodes could be more than 50 times less than the equivalent pristine high density nanowire networks, thus having major commercial implications. Using a laser ablation process, it is shown that the resulting films can be patterned into individual electrode structures, which is a pre‐requisite to touchscreen sensor fabrication. 相似文献