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91.
Natalie?L.?H.?Huisman Andrew?J.?Huisman K.?G.?KarthikeyanEmail author 《Nutrient Cycling in Agroecosystems》2017,109(1):29-42
Excess phosphorus (P) is generally responsible for the eutrophication of Midwestern surface waters and causes algal blooms, fish kills, and other detrimental ecological effects. In-stream transport of dissolved and particulate P (PP), under both stormflow and baseflow conditions, was studied in an agricultural Wisconsin watershed with diverse sizes of animal farm operations. Trends in P losses were compared both on an individual event and seasonal (spring, summer, fall) basis. In-stream P transport was characterized by high PP losses in the spring during periods of relatively little crop cover and high dissolved P losses in the fall, when surface coverage was still present. The majority of P (64–71%) was transported in the spring season during periods of high flow. Presence of high animal density at lower portions of the watershed resulted in increasing downstream P concentration and load (i.e., concentration dilution effects with increasing drainage area were absent). The baseflow TP concentrations were always above the USEPA eutrophication threshold [Ecoregion VII, level III-53: 0.08 mg L?1; (USEPA in Ambient water quality criteria recommendations. Information supporting the development of state and tribal nutrient criteria. Rivers and stream in nutrient ecoregion VII. EPA 822-B-00-018. https://www.epa.gov/sites/production/files/documents/rivers7.pdf, 2000)]. While upland conservation practices are necessary for non-point source pollution control, it is important to ensure that these practices afford protection during the spring time periods when agricultural fields are most vulnerable for offsite movement of sediments and associated constituents. 相似文献
92.
Finding home after homelessness: older men’s experiences in single-site permanent supportive housing
Victoria F. Burns Julie Deslandes- Leduc Natalie St-Denis Christine A. Walsh 《Housing Studies》2020,35(2):290-309
AbstractAlthough research on supportive housing models for older homeless adults is gaining momentum, few studies have considered the unique experiences of formerly homeless older adults residing in single-site permanent supportive housing (PSH). Drawing on the concepts of home and social exclusion, this qualitative case study explored the everyday experiences of 10 formerly homeless older men residing in single-site PSH. A constructivist grounded theory methodology and in-depth interviews revealed that participants felt largely at home in PSH because the congregate design and surveillance fostered a sense of safety. However, certain design features coupled with housing rules triggered processes of territorial exclusion. Further, members of minority groups experienced identity and institutional exclusion because of discrimination linked to their ethnicity, language, and sexual orientation. Recommendations are provided to promote more inclusive, home-like models of supportive housing for older homeless adults. 相似文献
93.
Coria-Avila Genaro A.; Gavrila Alex M.; Boulard Brigitte; Charron Natalie; Stanley Geoffrey; Pfaus James G. 《Canadian Metallurgical Quarterly》2008,122(2):396
The effects of the dopamine receptor antagonist flupenthixol were examined on the development of conditioned partner preference induced by paced copulation in female rats. In Experiment 1, ovariectomized, hormone-primed rats were conditioned to associate scented and unscented males with paced and nonpaced copulation, respectively. Females in Experiment 2 associated albino or pigmented males with paced or nonpaced copulation. Flupenthixol or saline was administered before each conditioning trial. During a final drug-free preference test, females could choose to copulate with either a pacing-related or nonpacing-related male. Saline-trained females copulated preferentially with the pacing-related male, whereas flupenthixol disrupted odor but not strain conditioning. The role of dopamine in conditioned partner preference depends on the type of stimuli to be learned. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Marchetta Natalie D. J.; Hurks Petra P. M.; Krabbendam Lydia; Jolles Jelle 《Canadian Metallurgical Quarterly》2008,22(1):74
In this study, the authors aimed to examine 4 domains of executive functioning in adults with attention-deficit/hyperactivity disorder (ADHD)--namely interference control, concept shifting, verbal fluency, and verbal working memory. Four groups of participants were included: (a) adults diagnosed with ADHD (ADHD-; n = 20), (b) adults diagnosed with both ADHD and 1 or more comorbid disorder(s) (ADHD+; n = 22), (c) adults referred for ADHD because of ADHD symptomatology but not diagnosed as such (non-ADHD; n = 34), and (d) healthy controls (n = 136). ADHD-related deficits (independent of comorbidity) were revealed for concept shifting and verbal working memory. In addition, the ADHD+ and non-ADHD groups displayed deficits in terms of general processing speed. Given that these deficits were not found in the ADHD- group, the authors contend that these deficits are likely attributable to comorbidity rather than ADHD itself. Contrary to the authors' expectations, these findings do not correspond with the cognitive subtype hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Akhil Vohra Heather L. Filiatrault Stanley D. Amyotte R. Stephen Carmichael Natalie D. Suhan Conrad Siegers Lorenzo Ferrari Gregory J. E. Davidson Tricia Breen Carmichael 《Advanced functional materials》2016,26(29):5222-5229
The development of stretchable electronic devices that are soft and conformable has relied heavily on a single material—polydimethylsiloxane—as the elastomeric substrate. Although polydimethylsiloxane has a number of advantageous characteristics, its high gas permeability is detrimental to stretchable devices that use materials sensitive to oxygen and water vapor, such as organic semiconductors and oxidizable metals. Failing to protect these materials from atmosphere‐induced decomposition leads to premature device failure; therefore, it is imperative to develop elastomers with gas barrier properties that enable stretchable electronics with practical lifetimes. Here, butyl rubber—a material with an intrinsically low gas permeability traditionally used in the innerliners of tires to maintain air pressure—is reinvented for stretchable electronics. This new material is smooth and optically transparent, possesses the low gas permeability typical of butyl rubber, and vastly outperforms polydimethylsiloxane as an encapsulating barrier to prevent the atmospheric degradation of sensitive electronic materials and the premature failure of functioning organic devices. The merits of transparent butyl rubber presented here position this material as an important counterpart to polydimethylsiloxane that will enable future generation stretchable electronics. 相似文献
96.
Spégel CF Heiskanen AR Kostesha N Johanson TH Gorwa-Grauslund MF Koudelka-Hep M Emnéus J Ruzgas T 《Analytical chemistry》2007,79(23):8919-8926
The two main metabolic pathways involved in sugar metabolism, i.e., the pentose phosphate pathway (PPP) and the glycolytic pathway (GP), were amperometrically monitored using a double-mediator system composed of menadione and ferricyanide. With the use of the Saccharomyces cerevisiae deletion mutant, EBY44, lacking the gene encoding for the branch point enzyme phosphoglucose isomerize, selective amperometric monitoring of the PPP, mainly producing NADPH, and the GP, mainly producing NADH, could be achieved. It was found that the bioelectrocatalytic current was primarily originating from NADPH. This conclusion was supported by metabolite flux analysis, confirming that, in the presence of menadione, the cells increase the rate of NADPH-producing reactions although these processes might be detrimental to cell survival. The higher rate of in vivo NADPH-dependent menadione reduction can be ascribed to the fact that the intracellular NADPH/NADP(+) ratio is much higher than NADH/NAD(+) as well as that the former ratio is more tightly controlled. This tight control over the cofactor ratios is lost upon cell disintegration as observed from spectrophotometric assays using crude cell extract, and amperometric investigations of permeabilized cells indicate a higher rate of NADH- than NADPH-dependent menadione reduction. These in vitro experiments show a higher activity of NADH-dependent than NADPH-dependent menadione-reducing dehydrogenases in S. cerevisiae cells. 相似文献
97.
Reichel A Schaible D Al Furoukh N Cohen M Schreiber G Piehler J 《Analytical chemistry》2007,79(22):8590-8600
Site-specific conjugation of proteins to surfaces, spectroscopic probes, or other functional units is a key task for implementing biochemical assays. The streptavidin-biotin interaction has proven a highly versatile tool for detection, quantification, and functional analysis of proteins. We have developed an approach for site-specific reversible biotinylation of recombinant proteins through their histidine tag using biotin conjugated to the multivalent chelator trisnitrilotriacetic acid (BTtris-NTA). Stable binding of BTtris-NTA to His-tagged proteins was demonstrated, which is readily reversed by addition of imidazole, enabling versatile conjugation schemes in solution as well as at interfaces. Gel filtration experiments revealed that His-tagged proteins bind to streptavidin doped with BTtris-NTA in a 2:1 stoichiometry. Furthermore, an increased binding affinity toward His-tagged proteins was observed for BTtris-NTA linked to streptavidin compared to tris-NTA in solution and on surfaces. These results indicate an efficient cooperative interaction of two adjacent tris-NTA moieties with a single His-tag, yielding an extremely tight complex with a lifetime of several days. We demonstrate several applications of BTtris-NTA including multiplexed capturing of proteins to biosensor surfaces, cell surface labeling, and Western blot detection. The remarkable selectivity of the His-tag-specific biotinylation, as well as the highly stable, yet reversible complex provides the basis for numerous further applications for functional protein analysis. 相似文献
98.
Built of sand – tension from unsaturation enable unimaginable sculptures. Partly saturated sand enables to form astonishing figures and sculptures of sand. Curvers are forming sculptures, which are presented in open air exhibitions. It can be shown, that suction caused by waterfilms in the pores of the soil is the physical reason for the tension stress of unsaturated soils. 相似文献
99.
Natalie R. Janzen Jamie Whitfield Lisa Murray-Segal Bruce E. Kemp John A. Hawley Nolan J. Hoffman 《International journal of molecular sciences》2021,22(17)
The AMP-activated protein kinase (AMPK), a central regulator of cellular energy balance and metabolism, binds glycogen via its β subunit. However, the physiological effects of disrupting AMPK-glycogen interactions remain incompletely understood. To chronically disrupt AMPK-glycogen binding, AMPK β double knock-in (DKI) mice were generated with mutations in residues critical for glycogen binding in both the β1 (W100A) and β2 (W98A) subunit isoforms. We examined the effects of this DKI mutation on whole-body substrate utilization, glucose homeostasis, and tissue glycogen dynamics. Body composition, metabolic caging, glucose and insulin tolerance, serum hormone and lipid profiles, and tissue glycogen and protein content were analyzed in chow-fed male DKI and age-matched wild-type (WT) mice. DKI mice displayed increased whole-body fat mass and glucose intolerance associated with reduced fat oxidation relative to WT. DKI mice had reduced liver glycogen content in the fed state concomitant with increased utilization and no repletion of skeletal muscle glycogen in response to fasting and refeeding, respectively, despite similar glycogen-associated protein content relative to WT. DKI liver and skeletal muscle displayed reductions in AMPK protein content versus WT. These findings identify phenotypic effects of the AMPK DKI mutation on whole-body metabolism and tissue AMPK content and glycogen dynamics. 相似文献
100.
Natalie L. Yanchar Susan A. Kirkland John C. LeBlanc Donald B. Langille 《Accident; analysis and prevention》2012