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1.
Scientometrics - Engaging in the international academic environment is now facilitated by a range of Academic Social Networks (ASNs) that are being used by an increasing number of early career and... 相似文献
2.
Shannon Lee Scott L. Carnahan Georgiy Akopov Philip Yox Lin-Lin Wang Aaron J. Rossini Kui Wu Kirill Kovnir 《Advanced functional materials》2021,31(16):2010293
Noncentrosymmetric (NCS) tetrel pnictides have recently generated interest as nonlinear optical (NLO) materials due to their second harmonic generation (SHG) activity and large laser damage threshold (LDT). Herein nonmetal-rich silicon phosphides RuSi4P4 and IrSi3P3 are synthesized and characterized. Their crystal structures are reinvestigated using single crystal X-ray diffraction and 29Si and 31P magic angle spinning NMR. In agreement with previous report RuSi4P4 crystallizes in NCS space group P1, while IrSi3P3 is found to crystallize in NCS space group Cm, in contrast with the previously reported space group C2. A combination of DFT calculations and diffuse reflectance measurements reveals RuSi4P4 and IrSi3P3 to be wide bandgap (Eg) semiconductors, Eg = 1.9 and 1.8 eV, respectively. RuSi4P4 and IrSi3P3 outperform the current state-of-the-art infrared SHG material, AgGaS2, both in SHG activity and laser inducer damage threshold. Due to the combination of high thermal stabilities (up to 1373 K), wide bandgaps (≈2 eV), NCS crystal structures, strong SHG responses, and large LDT values, RuSi4P4 and IrSi3P3 are promising candidates for longer wavelength NLO materials. 相似文献
3.
Shannon M. Fast Marta C. González James M. Wilson Natasha Markuzon 《Journal of the Royal Society Interface》2015,12(104)
Epidemic trajectories and associated social responses vary widely between populations, with severe reactions sometimes observed. When confronted with fatal or novel pathogens, people exhibit a variety of behaviours from anxiety to hoarding of medical supplies, overwhelming medical infrastructure and rioting. We developed a coupled network approach to understanding and predicting social response. We couple the disease spread and panic spread processes and model them through local interactions between agents. The social contagion process depends on the prevalence of the disease, its perceived risk and a global media signal. We verify the model by analysing the spread of disease and social response during the 2009 H1N1 outbreak in Mexico City and 2003 severe acute respiratory syndrome and 2009 H1N1 outbreaks in Hong Kong, accurately predicting population-level behaviour. This kind of empirically validated model is critical to exploring strategies for public health intervention, increasing our ability to anticipate the response to infectious disease outbreaks. 相似文献
4.
Emer Shannon Nissreen Abu‐Ghannam 《International Journal of Food Science & Technology》2018,53(9):2195-2204
Brown seaweeds contain a number of bioactive compounds. The xanthophyll, fucoxanthin, has in vivo efficacy against disorders such as type 2 diabetes, obesity and cancer. Organic solvents are traditionally employed to extract fucoxanthin, but carry a toxic chemical and environmental burden. The aim of this study was to optimise a fucoxanthin extraction method using enzymes, water, low‐temperature dehydration and mechanical blending, to produce yields comparable to those achieved with an organic solvent (acetone). Response surface methodology was applied, using Fucus vesiculosus as a model species. A fucoxanthin yield of 0.657 mg g?1 (dry mass) was obtained from F. vesiculosus blade using the enzymatic method, equivalent to 94% of the acetone‐extracted yield. Optimum extraction parameters were determined to be enzyme‐to‐water ratio 0.52%, seaweed‐to‐water ratio 5.37% and enzyme incubation time 3.05 h. These findings may be applied to the development of value‐added nutraceutical products from seaweed. 相似文献
5.
Xiaobo Dong Halle D. Shannon Caleb Parker Samantha De Jesus Isabel C. Escobar 《American Institute of Chemical Engineers》2020,66(1):e16790
Petroleum-derived solvents commonly used in membrane fabrication are often hazardous and toxic, so the investigation of safer alternatives is important. In this study, two low-hazard solvents, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv® PolarClean) and gamma-valerolactone (GVL), were investigated as sole solvents and as cosolvents to cast polysulfone membranes via nonsolvent induced phase inversion. Normalized viscosity was introduced as an indicator of dope solution homogeneity and was used to compare the required time of mixing to achieve full dissolution of the polymer in the different solvents/solvent mixtures. All dope solutions made with low-hazard solvents were found to be more viscous than those made with traditional solvents, which meant additional mixing time was needed, and that fabricated membranes were morphologically different. With respect to operation, membranes cast from dope solutions containing equal amounts of PolarClean and GVL displayed the most similar flux curves and solute rejection to those made using the traditional solvent tested. 相似文献
6.
Dr. Ilhem Khelifi Shannon Pecnard Dr. Guillaume Bernadat Dr. Jérome Bignon Dr. Hélène Levaique Dr. Joëlle Dubois Dr. Olivier Provot Dr. Mouad Alami 《ChemMedChem》2020,15(16):1571-1578
In this article, we report the synthesis and biological properties of a series of novel oxazepines related to isoCA-4 having significant antitumor properties. Among them, three oxazepin-9-ol derivatives display a nanomolar or a sub-nanomolar cytotoxicity level against five human cancer cell lines (HCT116, U87, A549, MCF7, and K562). It was demonstrated that the lead compound in this series inhibits tubulin assembly with an IC50 value of 1 μM and totally arrests the cellular cycle in the G2/M phase at the low concentration of 5 nM in HCT116 and K562 cells. Molecular modeling studies perfectly corroborates these promising results. 相似文献
7.
Using visual assessment as a foundation for greenway planning in the St. Lawrence River Valley 总被引:2,自引:0,他引:2
The growth of the ‘greenway’ as a fundamental planning concept has provided guidance for many communities locally and around the world. In the St. Lawrence River Valley, the idea is providing a common physical and cultural reference for the management of landscapes in communities along a 100 mile international corridor. Over the past 10 years, the College of Environmental Science and Forestry of the State University of New York has worked with the St. Lawrence-Eastern Ontario Commission to examine the unique visual and scenic resources of the region as the foundation for establishing a greenway tracing the St. Lawrence River. Although the idea of a greenway in the St. Lawrence River Valley is not new or unusual, the inventory and assessment of visual or scenic linear resources as a foundation is a departure from typical practice, and an experiment in defensible and rational planning. As a major summer tourism destination, the region is well aware of the critical value of its scenic resources. In our effort to identify and assess various vital resources for planning, we found an indicator in the visual nature of the landscape—both as a resource in and of itself, and as a reflection of the underlying values held by local communities for natural and cultural resources. This paper describes, as a case study, the process used to identify and assess visual and scenic resources in the region, and the use of the resulting database to initiate delineation of the proposed greenway. A discussion of the rationale and significance of the method is presented, including comments on the direction and progress in the region today. 相似文献
8.
Home ownership and access to opportunity are foundations of the American ethos. While little research has explicitly examined a relationship between home ownership and opportunity, considerable empirical work has examined how home ownership impacts important elements of local opportunity structures as well as individual subjective perceptions of those structures. Available evidence suggests that home ownership may affect the opportunity structure by enhancing neighbourhood stability and civic involvement in local voluntary and political affairs. Home ownership may also impact perceptions of opportunity by increasing financial resources, enhancing psychological and physical health, and influencing the behaviour of youth. There is a great need for additional research that directly assesses the impacts of home ownership on local objective opportunity structures and the perception of those structures. 相似文献
9.
Application of real-time quantitative PCR for the detection of selected bacterial pathogens during municipal wastewater treatment 总被引:5,自引:0,他引:5
Bacteria were detected at five stages of municipal wastewater treatment using TaqMan(R) real-time quantitative PCR (qPCR). Thirteen probe and primer sets were tested for diverse pathogens that may be present in wastewater, including Aeromonas hydrophila, Bacillus cereus, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, E. coli O157:H7, Helicobacter pylori, Klebsiella pneumoniae, Legionella pneumophila, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella sp., and Staphylococcus aureus. The sensitivity of the assay was 100 fg of genomic DNA (=22 gene copies), based on a standard curve generated using A. hydrophila purified DNA. Samples from five stages of wastewater treatment were collected, including raw wastewater, primary effluents, mixed liquor, waste activated sludge and final effluents. In duplicate samples, E. coli, K. pneumoniae, C. perfringens and E. faecalis were detected throughout the wastewater process, and their numbers decreased by 3.52-3.98, 4.23-4.33, 3.15-3.39, and 3.24 orders of magnitude respectively, between the raw wastewater and final effluent stage. This qPCR method was effective for the detection of pathogens in wastewater and confirmed that the risk of exposure to pathogens in the wastewater discharge was well within the Environment Canada guidelines. 相似文献
10.
Hong GH Baskaran M Molaroni SM Lee HM Burger J 《The Science of the total environment》2011,409(19):3638-3648
A number of caribou and muskoxen samples from the western Alaskan Arctic and fish samples from the Aleutian Islands were collected between 1998 and 2006 and analyzed for anthropogenic (90Sr and 137Cs) and natural radionculides (40 K, 210Pb and 226Ra), as part of the radiological assessment for the regional subsistence hunting communities in the first half of 2000s. We examined the relationship between the activities of these nuclides with the size of the fish. In caribou samples, concentration of 90Sr in muscle was below the detection limit of 0.14 Bq kg− 1 and 137Cs concentration in bones was below the detection limit of 0.15 Bq kg− 1.137Cs activity varied over an order of magnitude in caribou muscle samples with an average value of 2.5 Bq/kg wet wt. Average 137Cs activity in muskoxen muscle was found to be 9.7 Bq/kg wet wt. However, there were a little variation (less than 60%) in 210Pb, 40 K, and 226Ra in both muscle and bone of both caribou and muskoxen. The activities of total 210Pb in caribou and muskox bones were found to be 1-2 orders of magnitude higher than that of parent-supported 210Pb indicating the potential for dating of bones of terrestrial mammals (time elapsed since the death of the animal) based on the excess 210Pb method exists. In fish muscle samples, 137Cs activity varied from below detection limit to 154 mBq/kg wet wt. and its content increased with the size of the fish due to its transfer through the food chain. Among the seven fish species investigated, 210Pb activities varied almost an order of magnitude; however, 40K and 226Ra activities varied less than a factor of two. Total annual effective dose due to 90Sr and 137Cs from the ingestion of those terrestrial and marine meats was estimated to be negligible (ca. 9 μSV/a) compared to the natural radionuclides present thus posing negligible radiological threat to humans. 相似文献