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51.
Marie E. Portuallo David Y. Lu Gretchen M. Alicea Joel Bolling Rebecca Lee Jennifer McQuade Allison Betof Warner Michael Davies Ashani Weeraratna Jessie Villanueva Vito W. Rebecca 《Pigment cell & melanoma research》2023,36(5):441-447
The inaugural Diversity and Inclusion in Science Session was held during the 2021 Society for Melanoma Research (SMR) congress. The goal of the session was to discuss diversity, equity, and inclusion in the melanoma research community and strategies to promote the advancement of underrepresented melanoma researchers. An international survey was conducted to assess the diversity, equity, and inclusion (DEI) climate among researchers and clinicians within the Society for Melanoma Research (SMR). The findings suggest there are feelings and experiences of inequity, bias, and harassment within the melanoma community that correlate with one's gender, ethnic/racial group, and/or geographic location. Notably, significant reports of inequity in opportunity, discrimination, and sexual harassment demonstrate there is much work remaining to ensure all scientists in our community experience an academic workplace culture built on mutual respect, fair access, inclusion, and equitable opportunity. 相似文献
52.
Gerlach NM McGlothlin JW Parker PG Ketterson ED 《Proceedings. Biological sciences / The Royal Society》2012,279(1730):860-866
In many species, each female pairs with a single male for the purpose of rearing offspring, but may also engage in extra-pair copulations. Despite the prevalence of such promiscuity, whether and how multiple mating benefits females remains an open question. Multiple mating is typically thought to be favoured primarily through indirect benefits (i.e. heritable effects on the fitness of offspring). This prediction has been repeatedly tested in a variety of species, but the evidence has been equivocal, perhaps because such studies have focused on pre-reproductive survival rather than lifetime fitness of offspring. Here, we show that in a songbird, the dark-eyed junco (Junco hyemalis), both male and female offspring produced by extra-pair fertilizations have higher lifetime reproductive success than do offspring sired within the social pair. Furthermore, adult male offspring sired via extra-pair matings are more likely to sire extra-pair offspring (EPO) themselves, suggesting that fitness benefits to males accrue primarily through enhanced mating success. By contrast, female EPO benefited primarily through enhanced fecundity. Our results provide strong support for the hypothesis that the evolution of extra-pair mating by females is favoured by indirect benefits and shows that such benefits accrue much later in the offspring's life than previously documented. 相似文献
53.
54.
Ze'ev Barak Bela Ohana Yael Allon Joel Margalit 《Applied microbiology and biotechnology》1987,27(1):88-93
Summary PST, a spontaneous mutant of Bacillus thuringiensis var. israelensis (B.t.i.) resistant to penicillin, streptomycin and tetracycline was isolated by serial selections. In the absence of antibiotics it showed genetic stability for 16 generations. Mosquito larvicidal activity of PST was similar to that of B.t.i., its parental strain. It also maintained the specific antigenicity of B.t.i. although its rate of growth was somewhat lower, a generation time of 55 min for PST vs. 38 min for B.t.i. Cell concentration plays a major role in the phenomenon of PST resistance to penicillin.This antibiotic resistant mutant of b.t.i. provides us with an efficient tool to trace B.t.i. among the indigenous bacteria present in septic habitats in the field as well as inside the larval gut. 相似文献
55.
How two species interact during and after colonization influences which of them will be present in each stage of succession.
In the tolerance model of ecological succession in a patchy environment, empty patches can be colonized by any species, but
the ability to tolerate reduced resource levels determines which species will exclude the other. Here, we analyze a meta-population
model of the possible roles of competition in colonization and succession, using non-linear Markov chains as a mathematical
framework. Different kinds of competition affect the final equilibrial, abundances of the species involved in qualitatively
different ways. An explicit criterion is given to determine which interactions have stronger effects on the final equilibrial
levels of the weaker, species. Precise conditions are stated for the co-existence of both species. Both species are more likely
to co-exist in the presence of an intermediate disturbance frequency. 相似文献
56.
William C. Hahn Joel S. Bader Theodore P. Braun Andrea Califano Paul A. Clemons Brian J. Druker Andrew J. Ewald Haian Fu Subhashini Jagu Christopher J. Kemp William Kim Calvin J. Kuo Michael T. McManus Gordon B. Mills Xiulei Mo Nidhi Sahni Stuart L. Schreiber Jessica A. Talamas Jonathan Weissman 《Cell》2021,184(5):1142-1155
57.
Xuyi Yue Zonghua Luo Hui Liu Kota Kaneshige Stanley M. Parsons Joel S. Perlmutter Zhude Tu 《Bioorganic & medicinal chemistry letters》2018,28(21):3425-3430
Vesicular acetylcholine transporter (VAChT) is a reliable biomarker for assessing the loss of cholinergic neurons in the brain that is associated with cognitive impairment of patients. 5-Hydrotetralin compound (±)-5-OH-VAT is potent (Ki?=?4.64?±?0.32?nM) and selective for VAChT (>1800-fold and 398-fold for σ1 and σ2 receptor, respectively) with favorable hydrophilicity (LogD?=?1.78), while (?)-5-OH-VAT originally serves as the radiolabeling precursor of (?)-[18F]VAT, a promising VAChT radiotracer with a logD value of 2.56. To evaluate (?)-5-OH-[18F]VAT as a radiotracer for VAChT, we performed in vitro binding assay to determine the potency of the minus enantiomer (?)-5-OH-VAT and plus enantiomer (+)-5-OH-VAT, indicating that (?)-5-OH-VAT is a more potent VAChT enantiomer. Radiosynthesis of (?)-5-OH-[18F]VAT was explored using three strategies. (?)-5-OH-[18F]VAT was achieved with a good yield (24?±?6%) and high molar activity (~37?GBq/µmol, at the end of synthesis) using a microwave assisted two-step one-pot procedure that started with di-MOM protected nitro-containing precursor (?)-6. MicroPET studies in the brain of nonhuman primate (NHP) suggest that (?)-5-OH-[18F]VAT readily penetrated the blood brain barrier and specifically accumulated in the VAChT-enriched striatum with improved washout kinetics from striatum compared to [18F]VAT. Nevertheless, the lower target to non-target ratio may limit its use for in vivo measurement of the VAChT level in the brain. 相似文献
58.
59.
Three divalent cation binding sites in the integrin β I domain have been shown to regulate ligand binding and adhesion. However, the degree of ligand binding and adhesion varies among integrins. The αLβ2 and α4β7 integrins show an increase in ligand binding affinity and adhesion when one of their ADMIDAS (adjacent to MIDAS, or the metal ion-dependent adhesion site) residues is mutated. By contrast, the α2β1, α5β1, and αIIbβ3 integrins show a decrease in binding affinity and adhesion when their ADMIDAS is mutated. Our study here indicated that integrin αVβ3 had lower affinity when the ADMIDAS was mutated. By comparing the primary sequences of these integrin subunits, we propose that one residue associated with the MIDAS (β3 Ala(252)) may account for these differences. In the β1 integrin subunit, the corresponding residue is also Ala, whereas in both β2 and β7 integrin subunits, it is Asp. We mutated the β3 residue Ala(252) to Asp and combined this mutant with mutations of one or two ADMIDAS residues. The mutant A252D showed reduced ligand binding affinity and adhesion. The ligand binding affinity and adhesion were increased when this A252D mutant was paired with mutations of one ADMIDAS residue. But when paired with mutations of two ADMIDAS residues the mutant nearly abolished ligand-binding ability, which was restored by the activating glycosylation mutation. Our study suggests that the variation of this residue contributes to the different ligand binding affinities and adhesion abilities among different integrin families. 相似文献
60.