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101.
Bernstein Bianca L.; Hofmann Barbara; Wade Priscilla 《Canadian Metallurgical Quarterly》1987,34(1):20
102 female and 67 male students (aged 17–74 yrs) from a large urban university rated their preferences for counselor gender for 9 client concerns and completed the Bem Sex-Role Inventory and a demographic questionnaire. Most Ss who expressed a preference for counselor gender preferred male counselors over female ones for all concerns other than problems with sexual issues. Preferences for male counselors were expressed more often, however, for vocational/academic and social/interpersonal concerns than for personal/intimate problems. Discriminant analyses revealed profiles of Ss who preferred male counselors or had no preference. Variables such as S sex-role, age, and race were found to be particularly useful in predicting gender preferences. Results are interpreted in terms of S. L. Bem's (see record 1981-25685-001) gender-schema theory. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Vehicle Collision with Bridge Piers 总被引:2,自引:0,他引:2
Sherif El-Tawil Edward Severino Priscilla Fonseca 《Canadian Metallurgical Quarterly》2005,10(3):345-353
Inelastic transient finite element simulations are used to investigate the demands generated during collisions between vehicles and bridge piers. Such collisions have occurred in the past, sometimes with catastrophic consequences. Two different types of trucks and two different bridge/pier systems are used in the simulations. The approach speeds for the trucks range from 55 to 135 kph. Various quantities of interest are extracted from the finite element results and used to develop a better understanding of the vehicle/pier crash process and to critique current specifications addressing such events. Although physical vehicle–pier impact tests were not carried out as part of this research, a variety of exercises are conducted to provide confidence in the analysis results. The simulations show that current collision design provisions could be unconservative and that there may be a population of bridge piers that are vulnerable to accidental or malicious impact by heavy trucks. 相似文献
103.
We reviewed four unpublished dissertations that used Levinson's theory to study women's adult development. The 39 biographies presented in these studies suggested that the women progressed through the same developmental periods as had men in Levinson's study and at roughly the same ages. Although the timing of the periods and the nature of the developmental tasks appeared to be similar, the ways of working on these tasks as well as the outcomes achieved were different. These differences are understood in part as consequences of the greater complexity of women's dreams and the problems encountered in living them out. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Omotayo A. Arotiba Rehana Malgas Priscilla G.L. Baker Selwyn F. Mapolie 《Electrochimica acta》2007,53(4):1689-1696
An electrochemical DNA biosensor (EDB) was prepared using an oligonucleotide of 21 bases with sequence NH2-5′-GAGGAGTTGGGGGAGCACATT-3′ (probe DNA) immobilized on a novel multinuclear nickel(II) salicylaldimine metallodendrimer on glassy carbon electrode (GCE). The metallodendrimer was synthesized from amino functionalized polypropylene imine dendrimer, DAB-(NH2)8. The EDB was prepared by depositing probe DNA on a dendrimer-modified GCE surface and left to immobilize for 1 h. Voltammetric and electrochemical impedance spectroscopic (EIS) studies were carried out to characterize the novel metallodendrimer, the EDB and its hybridization response in PBS using [Fe(CN)6]3−/4− as a redox probe at pH 7.2. The metallodendrimer was electroactive in PBS with two reversible redox couples at E°′ = +200 mV and E°′ = +434 mV; catalytic by reducing the Epa of [Fe(CN)6]3−/4− by 22 mV; conducting and has diffusion coefficient of 8.597 × 10−8 cm2 s−1. From the EIS circuit fitting results, the EDB responded to 5 nM target DNA by exhibiting a decrease in charge transfer resistance (Rct) in PBS and increase in Rct in [Fe(CN)6]3−/4− redox probe; while in voltammetry, increase in peak anodic current was observed in PBS after hybridization, thus giving the EDB a dual probe advantage. 相似文献
105.
Kazumi Kawasaki Ramos Bruna Candiani Lessio Ana Luisa Baraçal Mecê Priscilla Efraim 《Food science and biotechnology》2017,26(3):643-651
Uvaia (Eugenia pyriformis) frozen pulp processing generates a solid byproduct that can potentially contain important components of human nutrition. In this study, the drying of uvaia byproduct was studied. Two different drying treatments were tested: drying of wet waste and drying of waste with prior removal of water by centrifugation. Three drying temperatures were used: 40, 60, and 80 °C. Eight models were applied to fit the drying curves: Page, Lewis, Modified Page, Logarithmic, Midilli, Wang and Singh, Henderson and Pabis, and Weibull. Midilli presented an excellent fit to the curves. The effective moisture diffusivity of the uvaia byproduct ranged between 8.52 × 10?10 and 3.22 × 10?9 m2/s. The activation energy was 25.65 and 24.97 kJ/mol for non-centrifuged and centrifuged assays, respectively. The dried byproducts had a reduction of 3–21% of the total phenolic content against the control. The assay performed at 40 °C with centrifugation presented the lowest total color difference value. 相似文献
106.
Joana Marto Cecilia Sangalli Priscilla Capra Paola Perugini Andreia Ascenso Lídia Gonçalves 《Drug development and industrial pharmacy》2017,43(11):1792-1800
N-Acetyl-d-glucosamine (NAG) has been recently considered for topical treatment of hyperpigmentation disorders due to its inhibitory effect on thyrosinase enzymes in melanocytes. NAG is a precursor of hyaluronic acid, increasing its amount in skin, and consequently, preserving the skin hydration and elasticity. It may also act as an emulsion stabilizer.Solid lipid nanoparticles (SLN) are advanced delivery systems successfully used in pharmaceutical and cosmetic formulations for the improvement of active molecules penetration into the skin. Therefore, this work aimed to develop and characterize stable and scalable topical formulations containing NAG-loaded SLN.NAG was incorporated in SLN which were prepared by two high shear homogenizers and characterized regarding its morphology and particle size by transmission electron microscopy and photon correlation spectroscopy, respectively. Oil emulgel and hydrogel were used as carriers of NAG-loaded SLN. Several parameters were evaluated, including the droplet size distribution, rheology, pH and topical delivery by different techniques.It was observed that SLN size was significantly dependent on NAG incorporation and homogenization process. Most tested SLN parameters appeared to be quite suitable, that is, spherical and well-defined SLN with approximately 258?nm and ?30?mV. Hereafter, both gels containing SLN presented a pseudoplastic flow. Emulgel formulation containing NAG-loaded SLN allowed a higher NAG permeation through the SC compared to the respective control (about 0.8 μgcm?2?h?1).According to the results obtained, it can be suggested that NAG acts as an emulsion stabilizer. This stabilization was also particularly dependent on the homogenizer type which is quite important for scale-up process. This study demonstrated the potential of scalable SLN formulations to improve NAG topical delivery contributing to the improvement of skin properties on several skin disorders. 相似文献
107.
Luís Queirs-Reis Priscilla Gomes da Silva Jos Gonalves Andrea Brancale Marcella Bassetto Joo R. Mesquita 《International journal of molecular sciences》2021,22(19)
Coronavirus disease 19, or COVID-19, is an infection associated with an unprecedented worldwide pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which has led to more than 215 million infected people and more than 4.5 million deaths worldwide. SARS-CoV-2 cell infection is initiated by a densely glycosylated spike (S) protein, a fusion protein, binding human angiotensin converting enzyme 2 (hACE2), that acts as the functional receptor through the receptor binding domain (RBD). In this article, the interaction of hACE2 with the RBD and how fusion is initiated after recognition are explored, as well as how mutations influence infectivity and immune response. Thus, we focused on all structures available in the Protein Data Bank for the interaction between SARS-CoV-2 S protein and hACE2. Specifically, the Delta variant carries particular mutations associated with increased viral fitness through decreased antibody binding, increased RBD affinity and altered protein dynamics. Combining both existing mutations and mutagenesis studies, new potential SARS-CoV-2 variants, harboring advantageous S protein mutations, may be predicted. These include mutations S13I and W152C, decreasing antibody binding, N460K, increasing RDB affinity, or Q498R, positively affecting both properties. 相似文献
108.
Microbial electrolysis cells (MECs) are used to produce hydrogen gas from the current generated by bacteria, but low-cost alternatives are needed to typical cathode materials (carbon cloth, platinum and Nafion™). Stainless steel A286 was superior to platinum sheet metal in terms of cathodic hydrogen recovery (61% vs. 47%), overall energy recovery (46% vs. 35%), and maximum volumetric hydrogen production rate (1.5 m3 m−3 day−1 vs. 0.68 m3 m−3 day−1) at an applied voltage of 0.9 V. Nickel 625 was better than other nickel alloys, but it did not perform as well as SS A625. The relative ranking of these materials in MEC tests was in agreement with cyclic voltammetry studies. Performance of the stainless steel and nickel cathodes was further increased, even at a lower applied voltage (0.6 V), by electrodepositing a nickel oxide layer onto the sheet metal (cathodic hydrogen recovery, 52%, overall energy recovery, 48%; maximum volumetric hydrogen production rate, 0.76 m3 m−3 day−1). However, performance of the nickel oxide cathodes decreased over time due to a reduction in mechanical stability of the oxides (based on SEM–EDS analysis). These results demonstrate that non-precious metal cathodes can be used in MECs to achieve hydrogen gas production rates better than those obtained with platinum. 相似文献
109.
110.
Universal stress proteins (USPs) were originally discovered in Escherichia coli over two decades ago and since then their presence has been detected in various organisms that include plants, archaea, metazoans, and bacteria. As their name suggests, they function in a series of various cellular responses in both abiotic and biotic stressful conditions such as oxidative stress, exposure to DNA damaging agents, nutrient starvation, high temperature and acidic stress, among others. Although a highly conserved group of proteins, the molecular and biochemical aspects of their functions are largely evasive. This is concerning, as it was observed that USPs act as essential contributors to the survival/persistence of various infectious pathogens. Their ubiquitous nature in various organisms, as well as their augmentation during conditions of stress, is a clear indication of their direct or indirect importance in providing resilience against such conditions. This paper seeks to clarify what has already been reported in the literature on the proposed mechanism of action of USPs in pathogenic organisms. 相似文献