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1.
Loss of β-cell mass and function can lead to insufficient insulin levels and ultimately to hyperglycemia and diabetes mellitus. The mainstream treatment approach involves regulation of insulin levels; however, approaches intended to increase β-cell mass are less developed. Promoting β-cell proliferation with low-molecular-weight inhibitors of dual-specificity tyrosine-regulated kinase 1A (DYRK1A) offers the potential to treat diabetes with oral therapies by restoring β-cell mass, insulin content and glycemic control. GNF4877, a potent dual inhibitor of DYRK1A and glycogen synthase kinase 3β (GSK3β) was previously reported to induce primary human β-cell proliferation in vitro and in vivo. Herein, we describe the lead optimization that lead to the identification of GNF4877 from an aminopyrazine hit identified in a phenotypic high-throughput screening campaign measuring β-cell proliferation.  相似文献   
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Correlates of psychotic and psychoticlike symptoms were examined in 60 college students who scored deviantly high on the Perceptual Aberration Scale. High scorers on this scale who also scored high on both the Impulsive Nonconformity Scale and the Depression subscale of the General Behavior Inventory (GBI) showed the most deviant psychotic and psychoticlike symptoms. Moreover, performance on a task of referential communication, the Password Task, was significantly related to such symptoms. The Perceptual Aberration Scale, the Impulsive Nonconformity Scale, and the GBI Depression subscale are recommended for concurrent use in mass screening to select individuals likely to exhibit psychotic or psychoticlike symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Security countermeasures help ensure the confidentiality, availability, and integrity of information systems by preventing or mitigating asset losses from Cybersecurity attacks. Due to uncertainty, the financial impact of threats attacking assets is often difficult to measure quantitatively, and thus it is difficult to prescribe which countermeasures to employ. In this research, we describe a decision support system for calculating the uncertain risk faced by an organization under cyber attack as a function of uncertain threat rates, countermeasure costs, and impacts on its assets. The system uses a genetic algorithm to search for the best combination of countermeasures, allowing the user to determine the preferred tradeoff between the cost of the portfolio and resulting risk. Data collected from manufacturing firms provide an example of results under realistic input conditions.  相似文献   
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In bubble columns, the phenomena of mass and heat transfer as well as the reaction are closely linked to the complex fluid dynamics. Compartment modeling offers the opportunity to integrate these phenomena while enabling an axial and radial distribution with acceptable computing effort. This article includes methods for generating the compartment geometry and fluid dynamic parameters of this modeling approach, facilitating the opportunity to optimize an industrial bubble column.  相似文献   
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The use of experiments— particularly randomized controlled trials (RCTs) where subjects are randomly assigned to treatment and control conditions—has rarely been applied to the process of improving the design of energy efficiency programs and, more fundamentally, to determining the net savings from energy efficiency programs. This paper discusses the use of experimentation in the energy efficiency program field with the hope of explaining how these experiments can be used, and identifying the barriers to their use will cause more experimentation to occur. First, a brief overview of experimental methods is presented. This discussion describes the advantages and disadvantages of conducting experiments in the context of the development and evaluation of energy efficiency programs. It then discusses barriers to the use of experimental methods (including cost and equity issues) and suggests some ways of overcoming these barriers. Finally, recommendations are made for implementing key social experiments, discussing the types of energy efficiency programs and issues that can make use of experimentation and variables that one might use for selecting treatments.  相似文献   
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The present research investigated the effects of various strontium concentrations, in combination with different incubation periods, on mouse parthenogentic oocyte activation and blastocyst development. The results for blastocyst development showed a trend indicating that 10 mM strontium for 3 h was the optimal strontium protocol. Ethanol, an agent that incites oocyte activation via a monotonic rise in calcium, was employed as a control. The outcome of blastocyst formation arising from parthenogenic ethanol activation was significantly less (P < 0.001) than that achieved by the optimal strontium protocol. To assess the impact of strontium oocyte activation on embryo viability following fertilization with immature germ cells, the protocol of 10 mM strontium for 3 h was applied to oocytes injected with round spermatids and then compared with other protocols. The results indicate that following round-spermatid injection the benefits derived from strontium artificial oocyte activation are evident during both pre- and post-implantation development. However, in order to adjust the protocol to the most effective round-spermatid injection in relation to the oocyte cell cycle, injection was done 1.5 h after strontium activation followed by another 1.5 h activation in strontium. The implementation of round-spermatid injection in combination with this oocyte-activation protocol led to live-birth outcomes not significantly different to those outcomes obtained by mature spermatozoa.  相似文献   
9.
The kinetics of desulfurization of hydrogen sulfide, using metallic copper as desulfurizer, have been investigated over a range of temperatures and pressures of hydrogen sulfide. Our results indicate that there are two stages of reaction; activation energies for the first and second stages are 63 kJ/mol and 38 kJ/mol, respectively. Possible reaction mechanisms in which the initial rate is controlled by interface reaction and the later stage is controlled by diffusion through or in the Cu2S layer are consistent with the experimental data.  相似文献   
10.
博客和业内专家认为,电子邮件营销面临的最大挑战非常复杂,如收件箱传输能力或渲染。这是真的吗?一名博学的市场人员、设计师或程序员都可以轻易解决上述两个问题,而对于其他大多数人来说,问题就不是那么简单了。这才是真正的问题。大多数公司并不知道电子邮件营销的最佳实践,同时他们内部也缺少相关的专业资源。然而,却很少有公司意识到这个问题,因为即使是写得很糟糕的电子邮件似乎仍表现不错。未造成伤害,也没有犯错,不是吗?  相似文献   
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