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91.
Finkel Eli J.; Campbell W. Keith; Brunell Amy B.; Dalton Amy N.; Scarbeck Sarah J.; Chartrand Tanya L. 《Canadian Metallurgical Quarterly》2006,91(3):456
Tasks requiring interpersonal coordination permeate all spheres of life. Although social coordination is sometimes efficient and effortless (low maintenance), at other times it is inefficient and effortful (high maintenance). Across 5 studies, participants experienced either a high- or a low-maintenance interaction with a confederate before engaging in an individual-level task requiring self-regulation. Self-regulation was operationalized with measures of (a) preferences for a challenging task with high reward potential over an easy task with low reward potential (Study 1) and (b) task performance (anagram performance in Study 1, Graduate Record Exam performance in Studies 2 and 3, physical stamina in Study 4, and fine motor control in Study 5). Results uniformly supported the hypothesis that experiencing high-maintenance interaction impairs one's self-regulatory success on subsequent, unrelated tasks. These effects were not mediated through participants' conscious processes and emerged even with a nonconscious manipulation of high-maintenance interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
An intergroup extension of M. A. Hogg's (1992, 1993) social attraction hypothesis is proposed. Netball teams were investigated with measures assessing the relationship between (a) objective status; (b) "social beliefs" about intergroup status, stability, legitimacy, and permeability; (c) group identification, self-categorization, and prototypicality; (d) interpersonal relations and similarity; (e) depersonalized social attraction; and (f) true personal attraction. As predicted, group-membership based social attraction was directly influenced by self-categorization; indirectly influenced, through self-categorization, by intergroup status and stability beliefs; and uninfluenced by interpersonal relations. Social attraction (related to prototypicality and group identification) was relatively independent of personal attraction (related to similarity and interpersonal variables). Legitimacy, permeability, and the empirical co-occurrence of social and personal attraction in cohesive groups are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Sarah Gilgunn Keefe Murphy Henning Stckmann Paul J. Conroy T. Brendan Murphy R. William Watson Richard J. OKennedy Pauline M. Rudd Radka Saldova 《International journal of molecular sciences》2020,21(23)
The diagnosis and treatment of prostate cancer (PCa) is a major health-care concern worldwide. This cancer can manifest itself in many distinct forms and the transition from clinically indolent PCa to the more invasive aggressive form remains poorly understood. It is now universally accepted that glycan expression patterns change with the cellular modifications that accompany the onset of tumorigenesis. The aim of this study was to investigate if differential glycosylation patterns could distinguish between indolent, significant, and aggressive PCa. Whole serum N-glycan profiling was carried out on 117 prostate cancer patients’ serum using our automated, high-throughput analysis platform for glycan-profiling which utilizes ultra-performance liquid chromatography (UPLC) to obtain high resolution separation of N-linked glycans released from the serum glycoproteins. We observed increases in hybrid, oligomannose, and biantennary digalactosylated monosialylated glycans (M5A1G1S1, M8, and A2G2S1), bisecting glycans (A2B, A2(6)BG1) and monoantennary glycans (A1), and decreases in triantennary trigalactosylated trisialylated glycans with and without core fucose (A3G3S3 and FA3G3S3) with PCa progression from indolent through significant and aggressive disease. These changes give us an insight into the disease pathogenesis and identify potential biomarkers for monitoring the PCa progression, however these need further confirmation studies. 相似文献
94.
With the increasing interest in biopolymer nanofibers for diverse applications, the characterization of these materials in the physiological environment has become of equal interest and importance. This study performs first-time simulated body fluid (SBF) degradation and tensile mechanical analyses of blended fish gelatin (FGEL) and polycaprolactone (PCL) nanofibrous meshes prepared by a high-throughput free-surface alternating field electrospinning. The thermally crosslinked FGEL/PCL nanofibrous materials with 84–96% porosity and up to 60 wt% PCL fraction demonstrate mass retention up to 88.4% after 14 days in SBF. The trends in the PCL crystallinity and FGEL secondary structure modification during the SBF degradation are analyzed by Fourier transform infrared spectroscopy. Tensile tests of such porous, 0.1–2.2 mm thick FGEL/PCL nanofibrous meshes in SBF reveal the ultimate tensile strength, Young's modulus, and elongation at break within the ranges of 60–105 kPa, 0.3–1.6 MPa, and 20–70%, respectively, depending on the FGEL/PCL mass ratio. The results demonstrate that FGEL/PCL nanofibrous materials prepared from poorly miscible FGEL and PCL can be suitable for selected biomedical applications such as scaffolds for skin, cranial cruciate ligament, articular cartilage, or vascular tissue repair. 相似文献
95.
Sarah E. Towne Yatish T. Shah Gerald D. Holder Girish V. Deshpande Donald C. Cronauer 《Fuel》1985,64(7):883-889
Powhatan No. 5 and Bruceton coals were liquefied for 15–60 min at 653 K and 30 MPa in supercritical aqueous mixtures containing 10–20 wt% tetrahydroquinoline (THQ), quinoline or tetralin. The THQ-water mixtures produced the highest conversion to tetrahydrofuran (THF) soluble products (up to 74%). Tetralin-water, quinoline-water and pure water solvents gave increasingly lower yields of THF solubles. Addition of hydrogen to the quinoline-water solvent mixture increased yields slightly, but not to the level obtained using the THQ-water mixture.The yields of THF solubles in all instances depended upon the concentration of solvent in the mixture, with the 10 wt% THQ and 10 wt% tetralin (in water) giving higher yields than either 0 or 20 wt% concentrations. The nitrogen-containing solvents were chemically bonded to the THF-soluble product, as observed by g.p.c. 相似文献
96.
Sarah M. Kedziora Kristin Krker Lajos Mark Julia Binder Meryam Sugulle Martin Gauster Dominik N. Müller Ralf Dechend Nadine Haase Florian Herse 《International journal of molecular sciences》2021,22(7)
Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum. 相似文献
97.
Bilal Alashkar Alhamwe Daniel P. Potaczek Sarah Miethe Fahd Alhamdan Lukas Hintz Arslan Magomedov Holger Garn 《International journal of molecular sciences》2021,22(9)
Extracellular vesicles (EVs) are membranous structures, which are secreted by almost every cell type analyzed so far. In addition to their importance for cell-cell communication under physiological conditions, EVs are also released during pathogenesis and mechanistically contribute to this process. Here we summarize their functional relevance in asthma, one of the most common chronic non-communicable diseases. Asthma is a complex persistent inflammatory disorder of the airways characterized by reversible airflow obstruction and, from a long-term perspective, airway remodeling. Overall, mechanistic studies summarized here indicate the importance of different subtypes of EVs and their variable cargoes in the functioning of the pathways underlying asthma, and show some interesting potential for the development of future therapeutic interventions. Association studies in turn demonstrate a good diagnostic potential of EVs in asthma. 相似文献
98.
Tahergorabi R Sivanandan L Beamer SK Matak KE Jaczynski J 《Journal of the science of food and agriculture》2012,92(12):2534-2542
BACKGROUND: Skin‐on bone‐in chicken drumsticks were processed with isoelectric solubilization/precipitation to recover muscle proteins. The drumsticks were used as a model for dark chicken meat processing by‐products. The main objective of this study was conversion of dark chicken meat processing by‐products to restructured functional food product. An attempt was made to develop functional food product that would resemble respective product made from boneless skinless chicken breast meat. A three‐prong strategy to address diet‐driven cardiovascular disease (CVD)with a functional food was used in this study. The strategy included addition of three ingredients with well‐documented cardiovascular benefits: (i) ω‐3 polyunsaturated fatty acid‐rich oil (flaxseed‐algae, 9:1); (ii) soluble fiber; and (iii) salt substitute. Titanium dioxide, potato starch, polyphosphate, and transglutaminase were also added. The batters were formulated and cooked resulting in heat‐set gels. RESULTS: Color (L*a*b*), texture (torsion test, Kramer shear test, and texture profile analysis), thermal denaturation (differential scanning calorimetry), and gelation (dynamic rheology) of chicken drumstick gels and chicken breast gels were determined and compared. Chicken drumstick gels generally had comparable color and texture properties to the gels made from chicken breast meat. The endothermic transition (thermal denaturation) of myosin was more pronounced and gelation properties were better for the drumstick gels. CONCLUSION: This study demonstrated a feasibility to develop functional food made of muscle proteins recovered with isoelectric solubilization/precipitation from low‐value dark chicken meat processing by‐products. The functional food developed in this study was enriched with CVD‐beneficial nutrients and had comparable instrumental quality attributes to respective products made of chicken breast meat. Although the results of this study point towards the potential for a novel, marketable functional food product, sensory tests and storage stability study are recommended. Copyright © 2012 Society of Chemical Industry 相似文献
99.
Dietz J Koch J Kaur A Raja C Stein S Grez M Pustowka A Mensch S Ferner J Möller L Bannert N Tampé R Divita G Mély Y Schwalbe H Dietrich U 《ChemMedChem》2008,3(5):749-755
The interaction of the nucleocapsid NCp7 of the human immunodeficiency virus type 1 (HIV-1) Gag polyprotein with the RNA packaging signal Psi ensures specific encapsidation of the dimeric full length viral genome into nascent virus particles. Being an essential step in the HIV-1 replication cycle, specific genome encapsidation represents a promising target for therapeutic intervention. We previously selected peptides binding to HIV-1 Psi-RNA or stem loops (SL) thereof by phage display. Herein, we describe synthesis of peptide variants of the consensus HWWPWW motif on membrane supports to optimize Psi-RNA binding. The optimized peptide, psi-pepB, was characterized in detail with respect to its conformation and binding properties for the SL3 of the Psi packaging signal by NMR and tryptophan fluorescence quenching. Functional analysis revealed that psi-pepB caused a strong reduction of virus release by infected cells as monitored by reduced transduction efficiencies, capsid p24 antigen levels, and electron microscopy. Thus, this peptide shows antiviral activity and could serve as a lead compound to develop new drugs targeting HIV-1. 相似文献
100.
Simple protocols to convert molecular mechanics (MMX/PCMODEL), semiempirical PM3, and HF ab initio energies to accurate heats of formation for hydrocarbons with benzene rings are described. The data set consists of every hydrocarbon benzene derivative with an experimentally determined ΔHfo (g), and the ΔHfo (g)'s cover a range of -140 to +410 kJ/mol. The molecular structures are comprised of numerous structural types. Hierarchical sets of molecular structure parameters are defined to describe these molecules. The independent variables include atom types (level 1), group and ring terms (level 2), nonbonded atom interactions (level 3), and the calculated MMX, PM3 or ab initio HF energies, which contribute a final level 4 parameter for rectification of the ΔHfo (g) data. The additivity, level 1-3 parameters give an excellent correlation of the experimental ΔHfo (g)'s, average error = 3.4 kJ, and maximum error = 12.1 kJ. However, the correlations are further enhanced by addition of any level 4 parameter, with maximum improvement coming at the 6-31G*//STO-3G HF level of calculation. 相似文献