1,362 research outputs found
Decoration of titania nanofibres with anatase nanoparticles as efficient photocatalysts for decomposing pesticides and phenols
Using a series of partial phase transitions, an effective photocatalyst with fibril morphology was prepared. The catalytic activities of these materials were tested against phenol and herbicide in water. Both H-titanate and TiO2-(B) fibres decorated with anatase nanocrystals were studied. It was found that anatase coated TiO2-(B) fibres prepared by a 45 h hydrothermal treatment followed by calcination were not only superior photocatalysts but could also be readily separated from the slurry after photocatalytic reactions due to its fibril morphology
Locke, natural law and civil peace: Reply to Tate
In this comment, I reply to two objections John Tate raises against my discussion of the trajectory of Locke's ideas on toleration (in an earlier article published in EJPT, âLockeâs Tracts and the Anarchy of the Religious Conscienceâ) Tate maintains that I misunderstand the role of natural law and civil peace in Locke's thought. I defend my interpretation of the role of natural law and show that Tate is mistaken in his claim that Locke's concern to preserve civil peace conflicted with his separate concern to protect individual rights
Emotion, religious coping, stigma, and help-seeking attitudes among Asian Americans: Examination of moderated mediation
Using a moderated mediation model, we investigated how emotion regulation, emotion socialization, and religious coping affect the relationship between close othersâ stigma, self-stigma, and help-seeking among 106 Asian American students. We predicted that (a) self-stigma would positively mediate the close othersâ stigma and help-seeking attitudes association, and (b) emotion regulation, emotion socialization, and religious coping would moderate this relationship. Mediation and moderated mediation analyses indicated that close othersâ stigma predicted self-stigma, which in turn predicted help-seeking attitudes. This mediation model was moderated by religious coping but not emotional socialization or regulation; emotion regulation and help-seeking attitudes, however, were positively correlated
The ORBCOMM data communications system
The ORBCOMM system is designed to provide low-cost, two-way data communications for mobile and remote users. The communications system is ideally configured for low data rate applications where communicating devices are geographically dispersed and two-way communications through terrestrial means is cumbersome and not cost effective. The remote terminals use VHF frequencies which allow for the use of very small, low-cost terminals. ORBCOMM has entered into joint development agreements with several large manufacturers of both consumer and industrial electronics to design and build the remote terminals. Based on prototype work, the estimated retail cost of these units will range from 400 depending on the complexity of the design. Starting in the fall of 1993, ORBCOMM will begin service with a demonstration network consisting of two operating satellites. By the end of 1994, a full operating network of 26 satellites, four Gateway Earth Stations, and a Network Control Center will be in place. The full constellation will provide full coverage of the entire world with greater than 94 percent communications availability for the continental U.S. This paper describes the ORBCOMM system, the technology used in its implementation, and its applications
The Relationship of Achievement Motivation to Entrepreneurial Behavior: A Meta-Analysis
Entrepreneurship is a major factor in the national economy; thus, it is important to understand the motivational characteristics spurring people to become entrepreneurs and why some are more successful than others. In this study, we conducted a meta-analysis of the relationship between achievement motivation and variables associated with entrepreneurial behavior. We found that achievement motivation was significantly correlated with both choice of an entrepreneurial career and entrepreneurial performance. Further, we found that both projective and self-report measures of achievement motivation were valid. Finally, known group studies yielded a higher validity coefficient than did individual difference studies
Meeting Report: Alternatives for Developmental Neurotoxicity Testing
Developmental neurotoxicity testing (DNT) is perceived by many stakeholders to be an area in critical need of alternatives to current animal testing protocols and guidelines. To address this need, the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), the U.S. Environmental Protection Agency, and the National Toxicology Program are collaborating in a program called TestSmart DNT, the goals of which are to: (a) develop alternative methodologies for identifying and prioritizing chemicals and exposures that may cause developmental neurotoxicity in humans; (b) develop the policies for incorporating DNT alternatives into regulatory decision making; and (c) identify opportunities for reducing, refining, or replacing the use of animals in DNT. The first TestSmart DNT workshop was an open registration meeting held 13â15 March 2006 in Reston, Virginia. The primary objective was to bring together stakeholders (test developers, test users, regulators, and advocates for childrenâs health, animal welfare, and environmental health) and individuals representing diverse disciplines (developmental neurobiology, toxicology, policy, and regulatory science) from around the world to share information and concerns relating to the science and policy of DNT. Individual presentations are available at the CAAT TestSmart website. This report provides a synthesis of workgroup discussions and recommendations for future directions and priorities, which include initiating a systematic evaluation of alternative models and technologies, developing a framework for the creation of an open database to catalog DNT data, and devising a strategy for harmonizing the validation process across international jurisdictional borders
Conversion and Extraction of Insoluble Organic Materials in Meteorites
We endeavor to develop and implement methods in our laboratory to convert and extract insoluble organic materials (IOM) from low car-bon bearing meteorites (such as ordinary chondrites) and Precambrian terrestrial rocks for the purpose of determining IOM structure and prebiotic chemistries preserved in these types of samples. The general scheme of converting and extracting IOM in samples is summarized in Figure 1. First, powdered samples are solvent extracted in a micro-Soxhlet apparatus multiple times using solvents ranging from non-polar to polar (hexane - non-polar, dichloromethane - non-polar to polar, methanol - polar protic, and acetonitrile - polar aprotic). Second, solid residue from solvent extractions is processed using strong acids, hydrochloric and hydrofluoric, to dissolve minerals and isolate IOM. Third, the isolated IOM is subjected to both thermal (pyrolysis) and chemical (oxidation) degradation to release compounds from the macromolecular material. Finally, products from oxidation and pyrolysis are analyzed by gas chromatography - mass spectrometry (GCMS). We are working toward an integrated method and analysis scheme that will allow us to determine prebiotic chemistries in ordinary chondrites and Precambrian terrestrial rocks. Powerful techniques that we are including are stepwise, flash, and gradual pyrolysis and ruthenium tetroxide oxidation. More details of the integrated scheme will be presented
Improved test of Lorentz Invariance in Electrodynamics using Rotating Cryogenic Sapphire Oscillators
We present new results from our test of Lorentz invariance, which compares
two orthogonal cryogenic sapphire microwave oscillators rotating in the lab. We
have now acquired over 1 year of data, allowing us to avoid the short data set
approximation (less than 1 year) that assumes no cancelation occurs between the
and parameters from the photon
sector of the standard model extension. Thus, we are able to place independent
limits on all eight and parameters.
Our results represents up to a factor of 10 improvement over previous non
rotating measurements (which independently constrained 7 parameters), and is a
slight improvement (except for ) over results from
previous rotating experiments that assumed the short data set approximation.
Also, an analysis in the Robertson-Mansouri-Sexl framework allows us to place a
new limit on the isotropy parameter of
, an improvement of a factor of 2.Comment: Accepted for publication in Phys. Rev.
Drinker to Nursery Pig Ratio: Preference for a Drinker Location within a Pen and its Effects on Aggression
The objectives of this study were to (1) calculate aggressive interactions around the water bowl drinkers and to (2) determine preference for a water bowl location when pigs were offered either one, two or three water bowl drinkers per pen. Information is available on the current drinker to nursery pigâs ratios (drinker: pigs). In the UK producers are recommended 1:15, while in the US it is 1:10 for nursery pigs. A total of 225 crossbred were seven weeks of age. Conventional nursery pens had plastic flooring and all pigs had ad-libitum access to a commercially formulated diet. Water was delivered through a single stainless steel water bowl drinker and was provided ad libitum. All pigs received a natural light cycle from a curtain sided building. Nine pens were used for behavioral measures. Three treatments were compared. Treatment one (TRT 1; n = 3) was defined as one water bowl drinker per pen. Treatment two (TRT 2; n = 3) was defined as two water bowl drinkers per pen. Treatment three (TRT 3; n = 3) was defined as three water bowl drinkers per pen. One day prior to visual recording of drinking behavior, all pigs in a pen were identified with an individual number. One 12 V black and white CCTV camera was positioned over each water bowl drinker and behavior was recorded from 0700 to 1300 h over two consecutive days onto a DVR at 1 frame per second. The acquisition of drinking behavior (defined as the pig having its head in the water bowl drinker for 5 s or longer) was obtained by three experienced observers who viewed the recordings using 24 h mode (5 frame / s) onto the Observer software. Total number of aggressive interactions and length of aggression around the water bowl drinker over the 6 h period was not (P \u3c 0.05) different between the treatments. The total amount of time that nursery pigs spent when offered two (F vs. O) water bowl drinkers in a pen did not (P = 0.47) differ. However, when pigs were offered three (F vs. O vs. A) water bowl drinkers in a pen there was a difference (P \u3c 0.0001) for total amount of time spent at all three locations. In conclusion, pigs displayed a water bowl drinker preference with the alley location being the least favored; however, there were no difference in the number or length of aggressive interactions
Evaluation of time and temperature sufficient to inactivate porcine epidemic diarrhea virus in swine feces on metal surfaces
Objectives: To determine temperature and time applications sufficient to inactivate porcine epidemic diarrhea virus (PEDV) on a commercial livestock trailer, and practical within the constraints of current thermo-assisted drying and decontamination (TADD) capabilities in the industry.
Materials and methods: Thirty-two 4-week-old barrows were inoculated via oral gastric tube with 5 mL of either PEDV-negative feces (Neg; n = 4), untreated PEDV-positive feces (Pos; n = 4), or PEDV-positive feces subjected to 71°C for 10 minutes (71C-10M; n = 4), 63°C for 10 minutes (63C-10M; n = 4), 54°C for 10 minutes (54C-10M; n = 4), 38°C for 12 hours (38C-12H; n = 4), 20°C for 24 hours (20C-24H; n = 4), or 20°C for 7 days (20C-7D; n = 4). These pigs served as a bioassay to determine the infectivity of virus following treatment. Bioassay results were determined by reverse-transcriptase polymerase chain reaction on rectal swabs collected from the inoculated pigs on days 3 and 7 post inoculation.
Results: None of the pigs in the 71C-10M and 20C-7D groups became infected with PEDV. This result differed significantly from that of the Pos group (P \u3c .05). Results of the other groups did not differ significantly from that of the Pos group (P \u3e .05).
Implication: Holding PEDV in the presence of feces at 71°C for 10 minutes or at 20°C (room temperature) for 7 days is sufficient to inactivate the virus, preventing transmission under the conditions of this study
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