1,784 research outputs found
Hot Topics on the Web Strategies for Research
Some of the pitfalls of research on the Web are highlighted and exacerbated when the type of research being done is for "hot," controversial, or debatable topics. Who to trust, where to find the information, and how to determine what is reliable are all questions that will present themselves. However, the resources available on the Web are well suited for addressing many of the challenges of hot topic research. Finding points of view for obscure and well-known advocacy groups, finding the most current legislation on an issue, and finding recent events related to the issue are all actually enhanced and made easier by researching a topic on the Web. Knowing the pitfalls and benefits from the outset can make using the Web much more profitable for hot topics research. By using appropriate sites for topic identification, you can quickly build a useful collection of core sites. By knowing where to identify federal and state legislation, you can determine the state of current policy on a topic. And certainly, the Web is most likely to help with timely news and insight on advocacy groups that might provide no—or hard-to-find—printed materials on their positions. The following strategies and sources will facilitate efficient use of the Web for hot topics research that results in a full, well-informed view of the topic
Alternate metabolism during the dauer stage of the nematode Caenorhabditis elegans
When environmental conditions are unsuitable to support nematode reproduction, Caenorhabditis elegans arrests development before the onset of sexual maturity and specialised âdauerâ larvae, adapted for dispersal, and extended diapause are formed. Dauer larvae do not feed and their metabolism is dependent on internal food reserves. Adult worms which express defects in the insulin/insulin-like growth factor receptor DAF-2 also display enhanced longevity. Whole genome mRNA expression profiling has demonstrated that C. elegans dauer larvae and daf-2 adults have similar transcription profiles for a cohort of longevity genes. Important components of this enhanced longevity system are the a-crystallin family of small heat shock proteins, anti-ROS defence systems, increased activity of cellular detoxification processes and possibly also increased chromatin stability and decreased protein turnover. Anaerobic fermentation pathways are upregulated in dauer larvae, while long-lived daf-2 adults appear to have normal oxidative metabolism. Anabolic pathways are down regulated in dauer larvae (and possibly in daf-2 adults as well), and energy consumption appears to be diverted to enhanced cellular maintenance and detoxification processes in both systems
Cervicovaginal fluid and semen block the microbicidal activity of hydrogen peroxide produced by vaginal lactobacilli
BACKGROUND: H(2)O(2 )produced by vaginal lactobacilli is believed to protect against infection, and H(2)O(2)-producing lactobacilli inactivate pathogens in vitro in protein-free salt solution. However, cervicovaginal fluid (CVF) and semen have significant H(2)O(2)-blocking activity. METHODS: We measured the H(2)O(2 )concentration of CVF and the H(2)O(2)-blocking activity of CVF and semen using fluorescence and in vitro bacterial-exposure experiments. RESULTS: The mean H(2)O(2 )measured in fully aerobic CVF was 23 ± 5 μM; however, 50 μM H(2)O(2 )in salt solution showed no in vitro inactivation of HSV-2, Neisseria gonorrhoeae, Hemophilus ducreyii, or any of six BV-associated bacteria. CVF reduced 1 mM added H(2)O(2 )to an undetectable level, while semen reduced 10 mM added H(2)O(2 )to undetectable. Moreover, the addition of just 1% CVF supernatant abolished in vitro pathogen-inactivation by H(2)O(2)-producing lactobacilli. CONCLUSIONS: Given the H(2)O(2)-blocking activity of CVF and semen, it is implausible that H(2)O(2)-production by vaginal lactobacilli is a significant mechanism of protection in vivo
Coronary microvascular ischemia in hypertrophic cardiomyopathy - a pixel-wise quantitative cardiovascular magnetic resonance perfusion study.
BACKGROUND: Microvascular dysfunction in HCM has been associated with adverse clinical outcomes. Advances in quantitative cardiovascular magnetic resonance (CMR) perfusion imaging now allow myocardial blood flow to be quantified at the pixel level. We applied these techniques to investigate the spectrum of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and to explore its relationship with fibrosis and wall thickness. METHODS: CMR perfusion imaging was undertaken during adenosine-induced hyperemia and again at rest in 35 patients together with late gadolinium enhancement (LGE) imaging. Myocardial blood flow (MBF) was quantified on a pixel-by-pixel basis from CMR perfusion images using a Fermi-constrained deconvolution algorithm. Regions-of-interest (ROI) in hypoperfused and hyperemic myocardium were identified from the MBF pixel maps. The myocardium was also divided into 16 AHA segments. RESULTS: Resting MBF was significantly higher in the endocardium than in the epicardium (mean ± SD: 1.25 ± 0.35 ml/g/min versus 1.20 ± 0.35 ml/g/min, P < 0.001), a pattern that reversed with stress (2.00 ± 0.76 ml/g/min versus 2.36 ± 0.83 ml/g/min, P < 0.001). ROI analysis revealed 11 (31%) patients with stress MBF lower than resting values (1.05 ± 0.39 ml/g/min versus 1.22 ± 0.36 ml/g/min, P = 0.021). There was a significant negative association between hyperemic MBF and wall thickness (β = −0.047 ml/g/min per mm, 95% CI: −0.057 to −0.038, P < 0.001) and a significantly lower probability of fibrosis in a segment with increasing hyperemic MBF (odds ratio per ml/g/min: 0.086, 95% CI: 0.078 to 0.095, P = 0.003). CONCLUSIONS: Pixel-wise quantitative CMR perfusion imaging identifies a subgroup of patients with HCM that have localised severe microvascular dysfunction which may give rise to myocardial ischemia
Learning Objects for Library Instruction
This presentation was given at the Spring Workshop of the Academic Library Association of Ohio (ALAO) Instruction Interest Group on April 23, 2004. It discusses theory of learning objects and provides examples of learning object repositories. Techniques and software useful for building interactive learning objects, such as simulations, games, guided tasks (action mazes and Web Quests) are described. Evaluation of learning objects and use of the National Learning Infrastructure Initiative (NLII) observation tool are also covered. A workshop activity and a resource list are included
On the limits of Brans-Dicke spacetimes: a coordinate-free approach
We investigate the limit of Brans-Dicke spacetimes as the scalar field
coupling constant omega tends to infinity applying a coordinate-free technique.
We obtain the limits of some known exact solutions. It is shown that these
limits may not correspond to similar solutions in the general relativity
theory.Comment: LaTeX, 16 pp, report DF/UFPB/02-9
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Structure and composition of non-polar (11-20) InGaN nanorings grown by modified droplet epitaxy
Droplets grown by modified droplet epitaxy on non-polar (11-20) surfaces of InGaN epilayers on GaN have been seen to be associated with underlying ring-like structures. This work discusses droplet etching as a possible mechanism for ring formation, and droplet creeping as a possible explanation for the droplets sitting askew of the ring centre. Transmission electron microscopy (TEM) analysis shows the droplets to move along the c-axis, and indicates that they have a very high In content.The authors gratefully acknowledge funding from the Engineering and Physical Sciences Research Council (Grant number EP/M011 682/1).This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1002/pssb.20155263
Online Searching Skills: Development of an Inventory to Assess Self-Efficacy
Final revised version of article and the instrument.An instrument measuring online searching self-efficacy beliefs was developed. Several hypotheses related to self-efficacy and performance on assignments were tested. Students' efficacy beliefs rose significantly after an online course, and were related to good performance on assignments. The instrument may be used to measure changes in student attitudes after instruction
A Game-Based Multimedia Approach to Library Orientation
The Ohio State University Libraries Instruction Office, in collaboration with the Office of First Year Experience, created an innovative series of casual, interactive online games (matching, puzzles, crossword, multiple guess) to orient incoming freshmen to library resources. This presentation, given at the LOEX 2007 Conference in San Diego, California (May 2007), discusses the design and development process
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