966 research outputs found
Order Ten Implicit One-Step Hybrid Block Method for The Solution of Stiff Second-order Ordinary Differential Equations
A one-step hybrid block method for initial value problems of general second order Ordinary Differential Equations has been studied in this paper. The method is developed using interpolation and collocation techniques. The use of the power series approximate solution as an interpolation polynomial and its second derivative as a collocation equation is considered in deriving the method. Numerical analysis shows that the developed new method is consistent, convergent,nbspnbsp and order ten. The new method is then applied to solve the system of second-order ordinary differential equations and the accuracy is better when compared with the existing methods in terms of error
Effects of Smoking vs. Nicotine Replacement Therapy During Pregnancy on Childhood Health Outcomes: An Integrative Literature Review
PICOT: In pregnant women does the use of nicotine replacement therapy compared to smoking during pregnancy reduce the risk of future childhood health concerns?
Methods: A search was conducted on healthcare literature databases (Alt HealthWatch, AMED, CINAHL, and Medline).The initial search yielded 940 results related to the topic. Initial review narrowed the search to 25 articles. Articles were excluded if published before 2008. After reviewing the full articles and evaluating effectiveness of the studies, 12 studies met the criteria. These 12 articles focused on the effects of smoking and childhood outcomes, NRT, and success of NRT.
Findings: The articles concluded that NRT may aid in positive health outcomes since it excludes the risk factors associated with carbon monoxide and other carcinogens found in cigarettes. The NRT still delivers significant levels of nicotine exposure to the fetus and leads to pregnancy complications ending in low birth weight and preterm birth.
Recommendations: Further studies should be conducted on the effects of nicotine and NRT especially on birth outcomes and future childhood health concerns
1.19 Questionable suitability of OECD 237 protocol in risk assessment scheme?
Persistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy.Persistent xenobiotics are potentially hazardous for the bee larvae despite that they are not directly exposed in contrary to adult foraging bees. The crucial phase of larval development is the first six days after hatching when young larva grows exponentially and during this phase larvae are potentially exposed to xenobiotics via diet. That is why the life cycle of honeybee is still a great challenge for scientists. OECD reflected “this need” and adopted the OECD 237 protocol (Honey bee (Apis mellifera) larval toxicity test, single exposure) on 26th July 2013. The protocol addresses the requirements formulated by the United States, Canada, and Europe to test the toxicity of chemicals compounds on larvae fed with spiked food under laboratory conditions in a tier1 strategy
Untangling the Links Among Athletic Involvement, Gender, Race, and Adolescent Academic Outcomes
Although previous research has established that high school sports participation may be associated with positive academic outcomes, the parameters of the relationship remain unclear. Using a longitudinal sample of nearly 600 Western New York adolescents, this study examined gender- and race-specific differences in the impact of two dimensions of adolescent athletic involvement (“jock” identity and athlete status) on changes in school grades and school misconduct over a two-year interval. Female and black adolescents who identified themselves as “jocks” reported lower grades than those who did not, whereas female athletes reported higher grades than female nonathletes. Jocks also reported significantly more misconduct (including skipping school, cutting classes, having someone from home called to the school for disciplinary purposes, and being sent to the principal’s office) than nonjocks. Gender moderated the relationship between athlete status and school misconduct; athletic participation had a less salutary effect on misconduct for girls than for boys
Histological Study of the First Seven Days of Skin Wound Healing in Rats
The aim of this study was to elaborate a histological model of incisional skin wound healing in Sprague-Dawley rats. Under aseptic conditions two paravertebral full thickness skin incisions were performed on the back of 42 anesthetized male rats. Histological sections from tissue specimens were stained by hematoxylin and eosin, van Gieson, PAS + PSD, Mallory's phosphotungstic hematoxylin and azur and eosin and evaluated during the first seven days after surgery. Histological evaluation revealed that the regeneration of injured epidermis was completed five days after surgery. The inflammatory phase was recorded during the first three days of healing with the culmination of this phase between day one and day two. The beginning of the proliferative phase was dated to the first day and the peak during day five and day six. The initiation of the maturation and remodeling phase of the healing process was observed six days after wounding. At the layer of striated muscle, the centronucleated cells were described for the first time six days after surgery. The wound healing process of rat skin was histologically described during the first seven days. Results of this work can serve as an experimental model for further research using external pharmacological and physical factors (laser light, magnetic field) by which the wound healing can be favourably influenced
Effects of Tipranavir, Darunavir, and Ritonavir on Platelet Function, Coagulation, and Fibrinolysis in Healthy Volunteers
The use of HIV protease inhibitors (PIs) as part of antiretroviral therapy in the treatment of HIV-1 infection may be associated with an increased risk of bleeding. This prospective, randomized, open-label trial in healthy volunteers compared the effects of tipranavir/ritonavir (TPV/r), darunavir/ritonavir (DRV/r), and ritonavir (RTV) alone on platelet aggregation after a single dose and at steady-state concentrations. Subjects were selected on the basis of normal platelet aggregation and arachidonic acid (AA)-induced platelet aggregation inhibition after administration of a single 325-mg dose of aspirin. All 3 PI therapies were administered twice daily for 10 days
Zebrafish globin switching occures in two developmental stages and is controlled by the LCR
Globin gene switching is a complex, highly regulated process allowing expression of distinct globin genes at specific developmental stages. Here, for the first time, we have characterized all of the zebrafish globins based on the completed genomic sequence. Two distinct chromosomal loci, termed major (chromosome 3) and minor (chromosome 12), harbor the globin genes containing α/β pairs in a 5'-3' to 3'-5' orientation. Both these loci share synteny with the mammalian α-globin locus. Zebrafish globin expression was assayed during development and demonstrated two globin switches, similar to human development. A conserved regulatory element, the locus control region (LCR), was revealed by analyzing DNase I hypersensitive sites, H3K4 trimethylation marks and GATA1 binding sites. Surprisingly, the position of these sites with relation to the globin genes is evolutionarily conserved, despite a lack of overall sequence conservation. Motifs within the zebrafish LCR include CACCC, GATA, and NFE2 sites, suggesting functional interactions with known transcription factors but not the same LCR architecture. Functional homology to the mammalian α-LCR MCS-R2 region was confirmed by robust and specific reporter expression in erythrocytes of transgenic zebrafish. Our studies provide a comprehensive characterization of the zebrafish globin loci and clarify the regulation of globin switching
Alternative Numerical Techniques
Two new approaches to numerical QFT are presented.Comment: Lattice2002(theoretical), 3 page
An Optimized Half-Step Scheme Third derivative Methods for Testing Higher Order Initial Value Problems
An optimized half-step third derivative block scheme on testing third order initial value problems is presented in this article. This scheme suggests some certain points of evaluation which properly optimizes the truncation errors at point of formulas, the conditions that guarantee the properties of the method was considered and satisfied. However the develop scheme is used to test some third order optimized problems and the mathematical outcomes achieved confirms better calculation than the previous method we related with
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