Beyond von Neumann--logic operations in passive crossbar arrays alongside memory operations

The realization of logic operations within passive crossbar memory arrays is a promising approach to expand the fields of application of such architectures. Material implication was recently suggested as the basic function of memristive crossbar junctions, and single bipolar resistive switches (BRS) as well as complementary resistive switches (CRS) were shown to be capable of realizing this logical functionality. Based on a systematic analysis of the Boolean functions, we demonstrate here that 14 of 16 Boolean functions can be realized with a single BRS or CRS cell in at most three sequential cycles. Since the read-out step is independent of the logic operation steps, the result of the logic operation is directly stored to memory, making logic-in-memory applications feasible.     

Authentication of berries and berry-based food products

Berries represent one of the most important and high-valued group of modern-day health-beneficial “superfoods” whose dietary consumption has been recognized to be beneficial for human health for a long time. In addition to being delicious, berries are rich in nutrients, vitamins, and several bioactive compounds, including carotenoids, flavonoids, phenolic acids, and hydrolysable tannins. However, due to their high value, berries and berry-based products are often subject to fraudulent adulteration, commonly for economical gain, but also unintentionally due to misidentification of species. Deliberate adulteration often comprises the substitution of high-value berries with lower value counterparts and mislabeling of product contents. As adulteration is deceptive toward customers and presents a risk for public health, food authentication through different methods is applied as a countermeasure. Although many authentication methods have been developed in terms of fast, sensitive, reliable, and low-cost analysis and have been applied in the authentication of a myriad of food products and species, their application on berries and berry-based products is still limited. The present review provides an overview of the development and application of analytical chemistry methods, such as isotope ratio analysis, liquid and gas chromatography, spectroscopy, as well as DNA-based methods and electronic sensors, for the authentication of berries and berry-based food products. We provide an overview of the earlier use and recent advances of these methods, as well as discuss the advances and drawbacks related to their application.     

Optimization of Formulation Variables to Increase Antigen Entrapment in PLGA Particles

Efficient antigen entrapment is a key factor in preparation of poly (lactide-co-glycolide) acid (PLGA) vaccine formulations when the antigen is of short supply. This study presents a systematic approach in the testing of formulation variables with the objective to increase antigen entrapment in particles when the antigen stock concentration was low. Some of the experimental variables tested were poly (vinyl) alcohol (PVA) concentration in the inner (W₁) and outer (W₂) aqueous phase, W₁/oil (O) phase ratio and choice of organic solvent. The double emulsion solvent evaporation technique was applied to prepare PLGA particles with sonication as the emulsifying force. To measure antigen entrapment efficiency, the antigen (bovine serum albumin, BSA) was isotope labeled with ¹²⁵iodine (¹²⁵I). Our results demonstrated that a low PVA concentration in the inner aqueous (W₁) phase was beneficial to achieve a high encapsulation efficiency of antigen. On the contrary, in the outer aqueous (W₂) phase, a high PVA concentration favored antigen entrapment. We also demonstrated that decreasing the W₁ to O/polymer ratio contributed to increased entrapment efficiency. Testing different organic solvents (ethyl acetate, dichloromethane and chloroform), either alone or in combination, revealed that using chloroform as solvent resulted in the highest encapsulation of antigen and the highest production yield. Some of the results presented in this work are in disagreement with well-established formulation variables from previous studies.     

Attachment, separation, and women's vocational development: A longitudinal analysis.

This study tested a proposed model investigating the relations among attachment to and separation from parents, career self-efficacy, and career aspiration over a 5-year period with a sample of 207 young women. Results suggested that being attached to parents may lead to the development of confidence in pursuing career-related tasks, which in turn influences career aspiration. Separation from parents did not have direct effects on career self-efficacy. Results also indicated that women's career plans changed over a 5-year period with young women selecting more traditional and less prestigious careers than those to which they aspired in their senior year of high school. In addition, these women chose careers that underutilized their abilities. Finally, this sample of young women intended to have both careers and families, and the majority of these women ranked family as more important than career. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychology’s role in mathematics and science education.

Improving mathematics and science education in the United States has been a matter of national concern for over half a century. Psychology has a vital role to play in this enterprise. In this article, the authors review the kinds of contributions that psychology can make in four areas: (a) early understanding of mathematics, (b) understanding of science, (c) social and motivational aspects of involvement in mathematics and science, and (d) assessment of learning in mathematics and science. They also examine challenges to psychology’s playing a central and constructive role and make recommendations for overcoming those challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Responses of dairy cows supplemented with somatotropin during weeks 5 through 43 of lactation

Beginning at wk 5 of lactation, 136 cows (34 per treatment) were supplemented daily for 38 wk with 0, 10.3, 20.6, or 41.2 mg of recombinantly derived bST monomer. Cows were obtained from University of Kentucky, University of Minnesota, University of Pennsylvania, and The Ohio State University. Nine cows (4 at 0 mg/d, 1 at 10.3 mg/d, 1 at 20.6 mg/d, and 3 at 41.2 mg/d) did not complete the experiment because of health problems. Data from these cows were included in the reproduction and health databases but not in the production database. Cows supplemented with bST produced more milk, consumed more feed, had lower rates of BW gain, and had improved efficiencies of milk production (conversion of feed and NEL to milk). Additional increases in productivity were modest at 20.6 and 41.2 mg/d versus productivity at 10.3 mg/d of bST. Concentrations of fat, protein, and TS in milk were unaffected. At 10.3 mg/d, bST did not adversely affect reproduction or health.     

GaN高压LED在极小电流与极低温度下的光电特性

在图形化蓝宝石衬底上制备了串联结构的氮化镓(GaN)高压发光二极管(LED),分别在极小电流与极低温度下研究了其光电特性。结果表明,在极小电流区(I<1×10-8 A),主要输运机制为缺陷辅助隧穿。由于能带热收缩效应和辐射复合中心的热激活效应,随着温度升高,电致发光(EL)峰发生红移,半高宽(FWHM)增加;光输出强度与注入电流呈幂指数关系,表明极小电流下非辐射复合占主导,且载流子通过缺陷辅助隧穿至量子阱。在极低温度下(T~40 K)仍能观测到电致发光现象,表明载流子并未被完全冻析,在强场下可由施主态或受主态通过缺陷辅助隧穿至量子阱;随着注入电流增加,注入电荷的库伦电场对极化电场的屏蔽作用增强,导致发光峰发生明显的蓝移,能带填充效应则导致半高宽增加。     

JTE终端结构4H-SiC JBS二极管的击穿特性研究

研究了JTE终端结构4H-SiC JBS二极管的击穿特性.首先,理论模拟了JTE终端横向长度、离子注入剂量和界面电荷对击穿电压的影响.对工艺条件进行优化,制作了JTE终端结构4H-SiC JBS二极管.测试结果表明,器件的正向电压为1.52V,特征导通电阻为2.12 mΩ·cm2,击穿电压为1650 V.接着,研究器件...     

Male moth sensitivity to multicomponent pheromones: Critical role of female-released blend in determining the functional role of components and active space of the pheromone

In the present study male redbanded leafroller (Argyrotaenia velutinana), cabbage looper (Trichoplusia ni), and Oriental fruit moths, (Grapholita molesta), were tested in a flight tunnel to (1) the major pheromone component, (2) theZ/E pheromone component mixtures for Oriental fruit moth and redbanded leafroller, (3) and the female-released blends, over a series of dosages. Experiments were designed to test the hypothesis that male response downwind of a female is initiated by the major component and that minor components function only to elicit behaviors close to the female during close-range approach and courtship. The results did not support this hypothesis, but rather showed that males initiated upwind flight in significantly higher percentages to the complete blends of components, at all dosages, compared to single components or partial blends. Addition of minor components also signficantly enhanced male perception of the major component at lower dosages, resulting in completed flights to dosages of the major component that alone did not elicit any upwind flight. Our results support the concept that minor components function to enhance male sensitivity to the pheromone, and the specificity of the signal. Our results also support the hypothesis that the active space of the pheromone is a function of the upper and lower concentration thresholds for the blend of components, and not simply for the major component.