Demonstration of the feasibility of automated silicon solar cell fabrication

A study effort was undertaken to determine the process, steps and design requirements of an automated silicon solar cell production facility. Identification of the key process steps was made and a laboratory model was conceptually designed to demonstrate the feasibility of automating the silicon solar cell fabrication process. A detailed laboratory model was designed to demonstrate those functions most critical to the question of solar cell fabrication process automating feasibility. The study and conceptual design have established the technical feasibility of automating the solar cell manufacturing process to produce low cost solar cells with improved performance. Estimates predict an automated process throughput of 21,973 kilograms of silicon a year on a three shift 49-week basis, producing 4,747,000 hexagonal cells (38mm/side), a total of 3,373 kilowatts at an estimated manufacturing cost of $0.866 per cell or$1.22 per watt

Tablet Use and Social Skills in Autism Spectrum Disorder

The use of computer tablets can be beneficial for communication deficits in Autism. Studies have shown that tablets can have positive effects on individuals with Autism Spectrum Disorder (ASD) who have trouble communicating and expressing emotions. A systematic review was conducted to examine if tablets helped people with ASD develop social skills and expression of emotion. A search was conducted through PubMed. From the initial search, 117 articles were found. Of these 117 articles, 10 met the criteria for review along with 2 additional articles found from an additional source. These 12 articles underwent a systematic review. Tablet applications and video modeling were used to help the individuals with autism be able to learn emotions, recognize facial expressions, and communicate how they are feeling. Studies showed positive results when using multiple apps and videos. Although many more studies should be conducted in order to further support these results, this systematic review elucidated positive outcomes of tablet use

Negative-coupling resonances in pump-coupled lasers

We consider coupled lasers, where the intensity deviations from the steady state, modulate the pump of the other lasers. Most of our results are for two lasers where the coupling constants are of opposite sign. This leads to a Hopf bifurcation to periodic output for weak coupling. As the magnitude of the coupling constants is increased (negatively) we observe novel amplitude effects such as a weak coupling resonance peak and, strong coupling subharmonic resonances and chaos. In the weak coupling regime the output is predicted by a set of slow evolution amplitude equations. Pulsating solutions in the strong coupling limit are described by discrete map derived from the original model.Comment: 29 pages with 8 figures Physica D, in pres

Set-Rationalizable Choice and Self-Stability

A common assumption in modern microeconomic theory is that choice should be rationalizable via a binary preference relation, which \citeauthor{Sen71a} showed to be equivalent to two consistency conditions, namely $\alpha$ (contraction) and $\gamma$ (expansion). Within the context of \emph{social} choice, however, rationalizability and similar notions of consistency have proved to be highly problematic, as witnessed by a range of impossibility results, among which Arrow's is the most prominent. Since choice functions select \emph{sets} of alternatives rather than single alternatives, we propose to rationalize choice functions by preference relations over sets (set-rationalizability). We also introduce two consistency conditions, $\hat\alpha$ and $\hat\gamma$, which are defined in analogy to $\alpha$ and $\gamma$, and find that a choice function is set-rationalizable if and only if it satisfies $\hat\alpha$. Moreover, a choice function satisfies $\hat\alpha$ and $\hat\gamma$ if and only if it is \emph{self-stable}, a new concept based on earlier work by \citeauthor{Dutt88a}. The class of self-stable social choice functions contains a number of appealing Condorcet extensions such as the minimal covering set and the essential set.Comment: 20 pages, 2 figure, changed conten

The Effect of Pet Remedy on the Behaviour of the Domestic Dog (Canis familiaris)

This is the final version of the article. Available from MDPI via the DOI in this record.Stress-affected behaviour in companion animals can have an adverse effect on animal health and welfare and their relationships with humans. This stress can be addressed using chemical treatments, often in conjunction with behavioural therapies. Here, we investigated the efficacy of one commercial pharmacological intervention, Pet Remedy, advertised as a natural stress relief product for mammals. We aimed to see whether the product lowered stress-affected behaviour in dogs placed in a non-familiar environment. Behavioural responses of 28 dogs were video recorded using a double-blind, placebo-controlled, and counterbalanced repeated measures design. Dogs were exposed to both a placebo and Pet Remedy plug-in diffuser for 30 min with an intervening period of approximately 7 days between conditions. Multivariate regression analysis identified no significant differences in behaviour in either the Pet Remedy or placebo condition. In conclusion, in the current study, Pet Remedy did not reduce behavioural indicators indicative of a stress response. To determine the effects of Pet Remedy, future research using a larger sample size and controlling for breed would be beneficial.The study was sponsored by Unex Designs Ltd. (the company that manufactures Pet Remedy) and diffusers were provided by the company free of charge and without restrictions within the aims of the study however, it should be noted that Unex Designs Ltd. and all related personnel were not directly involved in the study. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results

Selective inhibition of carotenoid cleavage dioxygenases : phenotypic effects on shoot branching

Members of the carotenoid cleavage dioxygenase family catalyse the oxidative cleavage of carotenoids at various chain positions, leading to the formation of a wide range of apocarotenoid signalling molecules. To explore the functions of this diverse enzyme family, we have used a chemical genetic approach to design selective inhibitors for different classes of carotenoid cleavage dioxygenase. A set of 18 arylalkyl-hydroxamic acids was synthesised in which the distance between an iron-chelating hydroxamic acid and an aromatic ring was varied; these compounds were screened as inhibitors of four different enzyme classes, either in vitro or in vivo. Potent inhibitors were found that selectively inhibited enzymes that cleave carotenoids at the 9,10 position; 50% inhibition was achieved at sub-micromolar concentrations. Application of certain inhibitors at 100 microM to Arabidopsis node explants or whole plants led to increased shoot branching, consistent with inhibition of 9,10-cleavage

Concurrent Partnerships, Nonmonogamous Partners, and Substance Use Among Women in the United States

Objectives. We determined the prevalence, distribution, and correlates of US women's involvement in concurrent sexual partnerships, a sexual-network pattern that speeds population-wide HIV dissemination. Methods. We used sexual partnership dates reported by 7643 women in the 2002 National Survey of Family Growth to determine prevalence of concurrent sexual partnerships during the preceding 12 months. We examined associations between concurrency and sociodemographic characteristics and risk behaviors. Results. Prevalence of concurrent partnerships was 5.7% based on reported partnerships and 8.3% after adjustment for possible underreporting. Concurrency was associated with younger age (22 to 24 years: prevalence odds ratio [POR]=2.44) versus older age (40 to 44 years); marital status (formerly married: POR=6.56; never married: POR=3.81; vs married); Black race/ethnicity (POR=1.78); younger age at first sexual intercourse (12 to 13 years: POR=2.89) versus 18 years or older); having a nonmonogamous sexual partner (POR=6.96); having intercourse while ‘‘high’’ on drugs or alcohol (POR=1.61); binge drinking (POR=1.70); and crack or cocaine use (POR=2.72). Conclusions. The association of concurrency with nonmonogamous sexual partners and substance use suggests the existence of extensive sexual networks that link people at higher risk for HIV infection with increased opportunities for disseminating infection

Biochemical characterization and selective inhibition of β-carotene cis-trans isomerase D27 and carotenoid cleavage dioxygenase CCD8 on the strigolactone biosynthetic pathway

The first three enzymatic steps of the strigolactone biosynthetic pathway catalysed by β-carotene cis-trans isomerase Dwarf27 (D27) from Oryza sativa and carotenoid cleavage dioxygenases CCD7 and CCD8 from Arabidopsis thaliana have been reconstituted in vitro, and kinetic assays have been developed for each enzyme, in order to develop selective enzyme inhibitors. Recombinant OsD27 shows a UV-visible λ at 422 nm and is inactivated by silver(I) acetate, consistent with the presence of an iron-sulfur cluster that is used in catalysis. OsD27 and AtCCD7 are not inhibited by hydroxamic acids that cause shoot branching in planta, but OsD27 is partially inhibited by terpene-like hydroxamic acids. The reaction catalysed by AtCCD8 is shown to be a two-step kinetic mechanism using pre-steady-state kinetic analysis. Kinetic evidence is presented for acid-base catalysis in the CCD8 catalytic cycle and the existence of an essential cysteine residue in the CCD8 active site. AtCCD8 is inhibited in a time-dependent fashion by hydroxamic acids D2, D4, D5 and D6 (> 95% inhibition at 100 μm) that cause a shoot branching phenotype in A. thaliana, and selective inhibition of CCD8 is observed using hydroxamic acids D13H and D15 (82%, 71% inhibition at 10 μm). The enzyme inhibition data imply that the biochemical basis of the shoot branching phenotype is due to inhibition of CCD8

Smartphones and Social Health: Does Reduced Phone Use Lead to Better Social Health Outcomes?

Within the past decade, smartphones have become a necessity for modern life. However, there has been little to no experimental scientific research on how problematic use of these devices influences social health. Problematic smartphone use (PSU) may reduce our ability to communicate and understand one another, thereby reducing our ability to bond together, connect, and improve relationships. Research has examined many social health correlates of PSU, including technology’s impact on emotional intelligence, relationship satisfaction, and loneliness. However, these studies have been limited in causal validity by their survey-based approach. We propose the use of a pre-test/post-test experiment designed to reduce PSU in the treatment group to explore whether reducing PSU improves social health over time. We plan to help people reduce their phone use through an educational intervention over five weeks while tracking and analyzing their smartphone usage over that time. During these five weeks, we will measure social health indicators including emotional intelligence, empathy, social sensitivity, social anxiety, and loneliness

Draft Genome Sequence of Enterococcus faecalis UMB1309, Isolated from Catheterized Urine

A strain of Enterococcus faecalis was isolated from catheterized urine. Here, we present the draft genome sequence of this isolate, E. faecalis UMB1309. Analysis of the genome revealed multiple genes coding for virulence factors, as well as genes associated with antibiotic resistance