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61.
Wang Yu-Wei; Davidson M. Meghan; Yakushko Oksana F.; Savoy Holly Bielstein; Tan Jeffrey A.; Bleier Joseph K. 《Canadian Metallurgical Quarterly》2003,50(2):221
The authors present 3 studies on the initial validity and reliability of the Scale of Ethnocultural Empathy (SEE), a self-report instrument that measures empathy toward people of racial and ethnic backgrounds different from one's own. Specifically, the exploratory factor analysis yielded 4 factors: Empathic Feeling and Expression, Empathic Perspective Taking, Acceptance of Cultural Differences, and Empathic Awareness. A confirmatory factor analysis provided evidence for the stability and generalizability of this 4-factor solution. The SEE was correlated in the predicted directions with general empathy and attitudes toward people's similarities and differences. High internal consistency and test-retest reliability estimates were also found across the three studies. A discussion of how this scale can add to the research and practice regarding empathy and multicultural issues is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Lukin A Dauvalter V Kashulin N Yakovlev V Sharov A Vandysh O 《The Science of the total environment》2003,306(1-3):73-83
The Kuetsj?rvi lake ecosystem has been subject to intensive pollution generated by the Pechenganickel Company activities for more than 50 years. This article considers the effects of emissions from the copper-nickel smelter, that uses out-of-date technology, on a subarctic lake ecosystem. Six years of investigations revealed changes occurring at all ecosystem levels. It was found that the content of heavy metals (Cu, Ni, etc.) in lake sediments was dozens of times higher than the background values. Phyto- and zooplankton communities were in an unstable condition, while fish had pathologies of functionally important organs (gill, liver and kidney). The concentration of nickel in zoobenthos and fish was correlated its accumulation in sediments. 相似文献
63.
Tracing residual recombinant feed molecules during digestion and rumen bacterial diversity in cattle fed transgene maize 总被引:3,自引:0,他引:3
Ralf?EinspanierEmail author Bodo?Lutz Stefanie?Rief Oksana?Berezina Vladimir?Zverlov Wolfgang?Schwarz Johann?Mayer 《European Food Research and Technology》2004,218(3):269-273
The aim of this study was to trace selected nucleic acid and protein components of isogene versus Bt transgene maize within the bovine gastrointestinal tract (GIT). After feeding 22 cattle for 4 weeks with Bt176 maize, different plant genes and the recombinant protein CryIAb were quantified during digestion. Furthermore, a first initial characterization of rumen bacteria was approached, using 16rDNA gene sequencing comparing isogene- against transgene-fed animals. Ingesta samples of different GIT sections (rumen, abomasum, jejunum, colon) were analysed for chloroplast, maize invertase, zein and Bt toxin (CryIAb) gene fragments using quantitative real-time PCR. First, the initial gene dose of these maize genes was detected in maize silage. During digestion, a significant reduction of high-to-medium abundant plant gene fragments was shown depending on the dwell-time and the initial gene copy number. Immunoreactive CryIAb protein was quantified by ELISA in intestinal samples indicating a significant loss of that protein. Remarkable amounts of Bt toxin were found in all contents of the GIT and the protein was still present in faeces. For the first time, the influence of CryIAb transgene maize on rumen bacterial microflora was investigated compared to isogene material through analysis of 497 individual bacterial 16S rDNA sequences. In principle, specific bacterial leader-species could be identified in all bovine rumen extracts, but no significant influence of Bt176 maize feed was found on the composition of the microbial population. This investigation provides supplementing data to further evaluate the fate of novel recombinant material originating from transgene feed or food within the mammalian GIT. 相似文献
64.
6‐Methyluracil Derivatives as Bifunctional Acetylcholinesterase Inhibitors for the Treatment of Alzheimer's Disease 下载免费PDF全文
Dr. Vyacheslav E. Semenov Irina V. Zueva Dr. Marat A. Mukhamedyarov Dr. Sofya V. Lushchekina Dr. Alexandra D. Kharlamova Elena O. Petukhova Dr. Anatoly S. Mikhailov Dr. Sergey N. Podyachev Dr. Lilya F. Saifina Dr. Konstantin A. Petrov Oksana A. Minnekhanova Prof. Vladimir V. Zobov Prof. Evgeny E. Nikolsky Prof. Patrick Masson Prof. Vladimir S. Reznik 《ChemMedChem》2015,10(11):1863-1874
Novel 6‐methyluracil derivatives with ω‐(substituted benzylethylamino)alkyl chains at the nitrogen atoms of the pyrimidine ring were designed and synthesized. The numbers of methylene groups in the alkyl chains were varied along with the electron‐withdrawing substituents on the benzyl rings. The compounds are mixed‐type reversible inhibitors of cholinesterases, and some of them show remarkable selectivity for human acetylcholinesterase (hAChE), with inhibitory potency in the nanomolar range, more than 10 000‐fold higher than that for human butyrylcholinesterase (hBuChE). Molecular modeling studies indicate that these compounds are bifunctional AChE inhibitors, spanning the enzyme active site gorge and binding to its peripheral anionic site (PAS). In vivo experiments show that the 6‐methyluracil derivatives are able to penetrate the blood–brain barrier (BBB), inhibiting brain‐tissue AChE. The most potent AChE inhibitor, 3 d (1,3‐bis[5‐(o‐nitrobenzylethylamino)pentyl]‐6‐methyluracil), was found to improve working memory in scopolamine and transgenic APP/PS1 murine models of Alzheimer's disease, and to significantly decrease the number and area of β‐amyloid peptide plaques in the brain. 相似文献
65.
The objective of our work is to enable the reading of fragile scrolled historical parchments without the need to physically unravel them, thus providing valuable information to a wide range of scholarly disciplines. This problem has not been investigated by the computer vision community properly yet due to the need for parchment scanning technology: standard X-ray equipment is not sufficient as there is a requirement to extract out parchment ink in addition to the parchment's underlying structure. Effective data recovery is also compromised as content from historical scrolled documents is inaccessible due to the deterioration of the parchment. We create a 3D volumetric model of a scrolled parchment's underlying geometry and perform digital unwrapping of the parchment, producing a readable image of the text as an output. The proposed recovery framework consists of structure preserving anisotropic filtering in combination with robust segmentation, surface modelling and ink projection. We demonstrate with real examples how our algorithm is able to recover the underlying text and to solve the major challenge for scrolled parchment analysis, namely segmentation of connected layers and processing the data without user interaction. 相似文献
66.
67.
Ewa Tomaszewska Halyna Rudyk Izabela
wietlicka Monika Huas-Stasiak Janine Donaldson Marta Arczewska Siemowit Muszyski Piotr Dobrowolski Iwona Puzio Volodymyr Kushnir Oksana Brezvyn Viktor Muzyka Ihor Kotsyumbas 《International journal of molecular sciences》2021,22(24)
The current study examined the effects of exposure of pregnant dams to fumonisins (FBs; FB1 and FB2), from the seventh day of pregnancy to parturition, on offspring bone metabolism and properties. The rats were randomly divided into three groups intoxicated with FBs at either 0, 60, or 90 mg/kg b.w. Body weight and bone length were affected by fumonisin exposure, irrespective of sex or dose, while the negative and harmful effects of maternal FBs’ exposure on bone mechanical resistance were sex and dose dependent. The immunolocalization of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-Β ligand (RANKL), in bone and articular cartilage, indicated that the observed bone effects resulted from the FB-induced alterations in bone metabolism, which were confirmed by the changes observed in the Western blot expression of OPG and RANKL. It was concluded that the negative effects of prenatal FB exposure on the general growth and morphometry of the offspring bones, as a result of the altered expression of proteins responsible for bone metabolism, were dose and sex dependent. 相似文献
68.
Nicoleta Anghel Joachim Müller Mauro Serricchio Jennifer Jelk Peter Bütikofer Ghalia Boubaker Dennis Imhof Jessica Ramseier Oksana Desiatkina Emilia Punescu Sophie Braga-Lagache Manfred Heller Julien Furrer Andrew Hemphill 《International journal of molecular sciences》2021,22(19)
Toxoplasma gondii is an apicomplexan parasite that infects and proliferates within many different types of host cells and infects virtually all warm-blooded animals and humans. Trypanosoma brucei is an extracellular kinetoplastid that causes human African trypanosomiasis and Nagana disease in cattle, primarily in rural sub-Saharan Africa. Current treatments against both parasites have limitations, e.g., suboptimal efficacy and adverse side effects. Here, we investigate the potential cellular and molecular targets of a trithiolato-bridged arene ruthenium complex conjugated to 9-(2-hydroxyethyl)-adenine (1), which inhibits both parasites with IC50s below 10−7 M. Proteins that bind to 1 were identified using differential affinity chromatography (DAC) followed by shotgun-mass spectrometry. A trithiolato-bridged ruthenium complex decorated with hypoxanthine (2) and 2-hydroxyethyl-adenine (3) were included as controls. Transmission electron microscopy (TEM) revealed distinct ultrastructural modifications in the mitochondrion induced by (1) but not by (2) and (3) in both species. DAC revealed 128 proteins in T. gondii and 46 proteins in T. brucei specifically binding to 1 but not 2 or 3. In T. gondii, the most abundant was a protein with unknown function annotated as YOU2. This protein is a homolog to the human mitochondrial inner membrane translocase subunit Tim10. In T. brucei, the most abundant proteins binding specifically to 1 were mitochondrial ATP-synthase subunits. Exposure of T. brucei bloodstream forms to 1 resulted in rapid breakdown of the ATP-synthase complex. Moreover, both datasets contained proteins involved in key steps of metabolism and nucleic acid binding proteins. 相似文献
69.
Oksana Zholobko Xiang-Fa Wu Zhengping Zhou Ted Aulich Jivan Thakare John Hurley 《应用聚合物科学杂志》2020,137(39):49639
This article reports a comparative experimental study of the hygroscopic and mechanical behaviors of electrospun polybenzimidazole (PBI) nanofiber membranes and solution-cast PBI films. As-electrospun nonwoven PBI nanofiber mats (with the nanofiber diameter of ~250 nm) were heat-pressed under controlled temperature, pressure and duration for the study; lab-made solution-cast PBI films and commercially available PBI films (the PBI Performance Product Inc., Charlotte, NC) were used as the control samples. Thermogravimetric and microtensile tests were utilized to characterize the hygroscopic (moisture absorption) and mechanical properties of the PBI nanofiber membranes at varying heat-pressing conditions, which were further compared to those of solution-cast PBI films. Experimental results indicated that the PBI nanofiber membranes carried slightly higher thermal stability and less hygroscopic properties than those of solution-cast PBI films. In addition, heat-pressing conditions significantly influenced the mechanical properties of the resulting PBI nanofiber membranes. The stiffness and tensile strength increase with increasing either the heat-pressing pressure or duration, and relevant mechanisms were explored. The present study provides a rational understanding of the hygroscopic and mechanical behaviors of electrospun PBI nanofiber membranes and solution-cast PBI films that are beneficial to their reliable cutting-edge applications in high-temperature filtration, polymer electrolyte membranes (PEMs), etc. 相似文献
70.