Copiah-Lincoln Community College
UniversityWesson, Mississippi, United States
Research output, citation impact, and the most-cited recent papers from Copiah-Lincoln Community College (United States). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Copiah-Lincoln Community College
We adopt a statistical mechanical approach toward the optics of textured and inhomogeneous optical sheets. As a general rule, the local light intensity in such a medium will tend to be <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2 n^{2}(x)</tex> times greater than the externally incident light intensity, where <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n(x)</tex> is the local index of refraction in the sheet. This enhancement can contribute toward a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4 n^{2}(x)</tex> increase in the effective absorption of indirect-gap semiconductors like crystalline silicon.
BACKGROUND: Human prostate tissues are vulnerable to oxidative DNA damage. The risk of prostate cancer is lower in men reporting higher consumption of tomato products, which contain high levels of the antioxidant lycopene. We examined the effects of consumption of tomato sauce-based pasta dishes on lycopene uptake, oxidative DNA damage, and prostate-specific antigen (PSA) levels in patients already diagnosed with prostate cancer. METHODS: Thirty-two patients with localized prostate adenocarcinoma consumed tomato sauce-based pasta dishes for the 3 weeks (30 mg of lycopene per day) preceding their scheduled radical prostatectomy. Serum and prostate lycopene concentrations, serum PSA levels, and leukocyte DNA oxidative damage (ratio of 8-hydroxy-2'-deoxyguanosine [8-OHdG] to 2'-deoxyguanosine [dG]) were assessed before and after the dietary intervention. DNA oxidative damage was assessed in resected prostate tissue from study participants and from seven randomly selected prostate cancer patients. All statistical tests were two-sided. RESULTS: After the dietary intervention, serum and prostate lycopene concentrations were statistically significantly increased, from 638 nM (95% confidence interval [CI] = 512 to 764 nM) to 1258 nM (95% CI = 1061 to 1455 nM) (P<.001) and from 0.28 nmol/g (95% CI = 0.18 to 0.37 nmol/g) to 0.82 nmol/g (95% CI = 0.57 to 1.11 nmol/g) (P <.001), respectively. Compared with preintervention levels, leukocyte oxidative DNA damage was statistically significantly reduced after the intervention, from 0.61 8-OHdG/10(5) dG (95% CI = 0.45 to 0.77 8-OHdG/10(5) dG) to 0.48 8-OHdG/ 10(5) dG (95% CI = 0.41 to 0.56 8-OHdG/10(5) dG) (P =.005). Furthermore, prostate tissue oxidative DNA damage was also statistically significantly lower in men who had the intervention (0.76 8-OHdG/10(5) dG [95% CI = 0.55 to 0.96 8-OHdG/10(5) dG]) than in the randomly selected patients (1.06 8-OHdG/10(5) dG [95% CI = 0.62 to 1.51 8-OHdG/10(5) dG]; P =.03). Serum PSA levels decreased after the intervention, from 10.9 ng/mL (95% CI = 8.7 to 13.2 ng/mL) to 8.7 ng/mL (95% CI = 6.8 to 10.6 ng/mL) (P<.001). CONCLUSION: These data indicate a possible role for a tomato sauce constituent, possibly lycopene, in the treatment of prostate cancer and warrant further testing with a larger sample of patients, including a control group.
The low-frequency Raman scattering spectra of finite polymethylene chains, observed utilizing laser excitation, show a band progression whose frequencies vary inversely and continuously as a function of chain length. It was established that these transitions arise from the longitudinal acoustical vibration of the chain skeleton and its overtones. These results are related to recent theoretical calculations for crystal vibrations of the infinite chain and are found to be in excellent quantitative agreement. An accurate spectroscopic value is derived for the elastic modulus of polyethylene.
We report spectra isolating the LIII x-ray absorption threshold resonance of the elements iridium, platinum, and gold in the pure metallic state and in a variety of compounds. When normalized spectra obtained on the metals are subtracted from those obtained on the compounds, the resulting difference spectra are related to differences in the electronic structure of the absorber atom in the two types of environment. The change in area of a threshold resonance line obtained from such a difference spectrum can be related to the ionicity of the bonds of the absorber atom in its compounds. Measurements on supported platinum and iridium catalysts provide information on electronic changes in the metal due to the small size of the metal clusters or to interaction with the support material. Information on electronic changes due to interaction of the catalysts with gas molecules may also be obtained.
Grain boundary states play a dominant role in determining the electrical and photovoltaic properties of polycrystalline silicon by acting as traps and recombination centers. The recombination loss at grain boundaries is the predominant loss mechanism in polycrystalline solar cells. Cell parameters are calculated based on a transformation of grain boundary recombination centers to a uniform distribution of such states throughout the grain. Effective carrier lifetime is expressed in terms of grain size, allowing calculation of short-circuit current, open-circuit voltage, and fill factor. Excellent agreement is observed between theory and experiment for almost all device parameters. It is indicated that one could fabricate 10% efficiency polycrystalline solar cells from 20-μm-thick material if the grain size exceeds 500 μm.
Posttraumatic stress disorder is a serious and often disabling syndrome that develops in response to a traumatic event. Many individuals who initially develop the disorder go on to experience a chronic form of the condition that in some cases can last for many years. Among these patients, psychiatric and medical comorbidities are common, including early onset of age-related conditions such as chronic pain, cardiometabolic disease, neurocognitive disorders, and dementia. The hallmark symptoms of posttraumatic stress-recurrent sensory-memory reexperiencing of the trauma(s)-are associated with concomitant activations of threat- and stress-related neurobiological pathways that occur against a tonic backdrop of sleep disturbance and heightened physiological arousal. Emerging evidence suggests that the molecular consequences of this stress-perpetuating syndrome include elevated systemic levels of oxidative stress and inflammation. In this article we review evidence for the involvement of oxidative stress and inflammation in chronic PTSD and the neurobiological consequences of these processes, including accelerated cellular aging and neuroprogression. Our aim is to update and expand upon previous reviews of this rapidly developing literature and to discuss magnetic resonance spectroscopy as an imaging technology uniquely suited to measuring oxidative stress and inflammatory markers in vivo. Finally, we highlight future directions for research and avenues for the development of novel therapeutics targeting oxidative stress and inflammation in patients with PTSD.
Abstract A model of diffusion controlled mass transfer in liquid surfactant membranes is developed for uniform emulsion globules having no internal circulation. The solute is assumed to react instantaneously and irreversibly with the internal reagent at a reaction surface which advances into the globule as the reagent is consumed. A perturbation solution to the resulting non‐linear equations is presented. In general, the zero‐order, or pseudo‐steady state solution alone often gives an adequate representation of the process. Experimental data on the batch extraction of phenol from waste water are in good agreement with the model predictions.
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Extended x-ray absorption fine structure (EXAFS) studies were made in a series of highly dispersed metal catalysts to obtain structural information on the metal clusters present. Clusters of osmium, iridium, and platinum dispersed on silica or alumina were investigated. The metal clusters in the catalysts constituted 1.0 wt.% of the total mass. Chemisorption measurements indicated that the metal dispersions approached unity, where dispersion is defined as the ratio of surface metal atoms to total metal atoms in the clusters. When EXAFS data on the metal clusters are compared with data on the corresponding bulk metals, the lower average coordination number of the metal atoms in a cluster is evident. The decrease in coordination number is accompanied by an increase in the root mean square deviation of interatomic distance about the equilibrium value.
A “generalized brightness theorem” is derived that describes the thermodynamic limitations of the fluorescent planar concentrator. The maximum brightness concentration ratio allowed by thermodynamics is exp (hΔν/kT) where Δν is the Stokes shift in fluorescence.
BACKGROUND AND PURPOSE: EmboTrap is a novel stent retriever designed to achieve rapid and substantial flow restoration in acute ischemic stroke secondary to large-vessel occlusions. Here, we evaluated EmboTrap's safety and efficacy compared with established stent retrievers. METHODS: ARISE II (Analysis of Revascularization in Ischemic Stroke With EmboTrap) was a single-arm, prospective, multicenter study, comparing the EmboTrap device to a composite performance goal criterion derived using a Bayesian meta-analysis from the pivotal SWIFT (Solitaire device) and TREVO 2 (Trevo device) trials. Patients at 11 US and 8 European sites were eligible for inclusion if they had large-vessel occlusions and moderate-to-severe neurological deficits within 8 hours of symptom onset. The primary efficacy end point was achievement of modified Thrombolysis in Cerebral Ischemia (mTICI) reperfusion scores of ≥2b within 3 EmboTrap passes as adjudicated by the core laboratory. The primary safety end point was a composite of symptomatic intracerebral hemorrhage and serious adverse device effects. Secondary end points included functional independence (modified Rankin Scale, 0-2) and all-cause mortality at 90 days. RESULTS: value, <0.0001), and mTICI 2c/3 was 65%. After all interventions, mTICI 2c/3 was achieved in 76%, and mTICI ≥2b was 92.5%. The rate of first pass (mTICI ≥2b following a single pass) was 51.5%. The primary safety end point composite rate of symptomatic intracerebral hemorrhage or serious adverse device effects was 5.3%. Functional independence and all-cause mortality at 90 days were 67% and 9%, respectively. CONCLUSIONS: The EmboTrap stent-retriever mechanical thrombectomy device demonstrated high rates of substantial reperfusion and functional independence in patients with acute ischemic stroke secondary to large-vessel occlusions. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02488915.
BACKGROUND: Fatigue is one of the most frequent symptoms experienced by children with cancer during treatment. Effective management of fatigue is essential for improving children's quality of life. OBJECTIVE: The aim of this study was to examine the feasibility of a home-based aerobic exercise intervention to reduce fatigue in children with acute lymphoblastic leukemia (ALL). METHODS: A 6-week home-based aerobic exercise intervention was implemented for children who were in the intervention group, whereas patients in the control group received routine care. Multivariate analysis was used to examine the effects of the aerobic exercise intervention on the children's self-reported levels of fatigue at posttest and 1-month follow-up. Two types of analysis were used: intent-to-treat analysis and per-protocol analysis. RESULTS: This study was conducted with 22 children with ALL: 12 in the intervention group and 10 in the control group who were matched by age and sex. For per-protocol analysis, the finding indicated that children who received the exercise intervention reported significantly lower "general fatigue" subscale than those in the control group at the 1-month follow-up measurement. For intent-to-treat analysis, the findings indicated that there were no intervention and time effect for any of the 3 fatigue subscales at either posttest or 1-month follow-up. CONCLUSION: The finding indicated that the exercise program is feasible and warrants being tested in a clinical trial with a much larger sample of children for ALL. IMPLICATIONS FOR PRACTICE: It suggests that a home-based exercise program may reduce fatigue for ALL children who are undergoing maintenance chemotherapy.
Experimental results on friction coefficients obtained with a number of model additives in a four ball test apparatus have confirmed a recently proposed model of boundary lubrication. The values of adsorption free energies, calculated from friction coefficient data, agreed very closely with the free energies of adsorption determined by contact potential difference measurements. In general, the ranking order of additives based on the free energy of adsorption was the same as the published literature. The friction coefficient data obtained here were in excellent agreement with the published data on the chain length effect, chain saturation and branching and polar end-group structure. The ranking order within each group of single chain compounds was explained by the chain dispersion interactions. In general, the greater the chain dispersion interaction, the lower the minimum friction coefficient (the friction coefficient at monolayer coverage).
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTLow-temperature solution preparation of Group 4B, 5B and 6B transition-metal dichalcogenidesRussell R. Chianelli and Martin B. DinesCite this: Inorg. Chem. 1978, 17, 10, 2758–2762Publication Date (Print):October 1, 1978Publication History Published online1 May 2002Published inissue 1 October 1978https://pubs.acs.org/doi/10.1021/ic50188a014https://doi.org/10.1021/ic50188a014research-articleACS PublicationsRequest reuse permissionsArticle Views1240Altmetric-Citations99LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
A chronic inhalation study of unleaded gasoline vapor was conducted in mice and rats. The gasoline employed was typical of gasoline used in the US and contained 2% benzene. Groups of both sexes of B6C3F 1 mice and Fischer 344 rats were exposed to three concentrations of vapor, 67, 292, and 2056 ppm. Exposures were for 6 hours per day, 5 days per week, for periods ranging from 103 to 113 weeks. Interim sacrifices were conducted at 3, 6, 12, and 18 months. Laboratory studies, including hematological and biochemical determinations, were performed on rats at the interim sacrifices and at termination. Histopathological studies were conducted on both species at every interval. No consistent compound-related changes were seen in pharmacotoxic signs, mortality, hematological, or biochemical indices in either species. Significant depression of body weight gain was seen in both sexes of rats and male mice exposed to the highest level of gasoline vapor. On gross necropsy, a compound-related increase in liver nodules and masses was seen in female mice exposed to the high level. The most interesting observations were made on histopathological examination of the rats' tissues, and, of these, pathological changes in the kidneys were the most striking. Renal carcinomas or sarcomas, in the cortex or near the renal poles, were seen in the male rats at all dose levels, with some evidence of a dose-response relationship. One female rat in the intermediate dose group exhibited a renal sarcoma. Two mice had renal tumors, considered to be spontaneous neoplasms. Mention is made of new studies that have been prompted by the present findings.
For a growing number of organizations worldwide, cloud computing offers a quick and affordable way to tap into IT infrastructure as an Internet service. But obstacles and challenges remain.
This paper investigates the effect of lubricant composition on engine friction and connecting-rod bearing wear. Special attention has been given to polymer-thickened (VI improved) oils since these oils are characterized by shear-dependent viscosity and a simultaneous occurrence of viscous and elastic properties. The variables investigated in this study included lubricant viscosity, polymer type, and concentration. Two sets of engine studies were conducted, one to determine engine friction, the other to measure connecting-rod bearing wear, using irradiated bearings. For Newtonian fluids, the engine friction and wear response can be predicted from classical lubrication theory—that is, (a) friction decreases with increaing viscosity until a viscosity is reached where friction is a minimum; beyond this viscosity, further increases in viscosity result in increased friction. (b) Bearing wear decreases with increasing viscosity, but as a step function, not linearly, and the transition viscosity (of the step) corresponds to the viscosity which gives a minimum engine friction. The addition of polymeric VI improvers (non-Newtonian fluids) to mineral oil base stocks reduces engine friction and lowers bearing wear—the amount of friction and wear reduction depending on the polymer type and concentration. This paper demonstrates that polymer-thickened oils actually give better bearing wear performance than their comparable mineral oil counterparts despite the fact that they have a lower apparent viscosity at high rates of shear. In addition, it appears that temporary viscosity loss is not the sale cause of the reduced engine friction of polymer-thickened oils.
Background: Current management for a symptom cluster of pain, fatigue, and disturbed sleep in breast cancer patients has limited effects. Objective: The purposes of this prospective, randomized controlled pilot study were to (1) assess the feasibility and tolerability of auricular point acupressure (APA) intervention to manage pain, fatigue, and sleep disturbance in breast cancer patients and (2) provide an initial appraisal of effect size as compared with a control intervention. Methods: Thirty-one participants were randomized into either an active APA group (n = 16) or a control APA group (n = 15), which included the sham APA treatment not related to the symptoms. All participants received the APA once a week for 4 weeks. Self-report measures were obtained at baseline, weekly during intervention, at end of intervention, and at a 1-month follow-up. Results: For the 4-week of APA treatment, the retention rate was 88% for the active APA group and 73% for the control APA group. After 4 weeks of APA, participants in the active APA treatment had reported a reduction of 71% in pain, 44% in fatigue, 31% in sleep disturbance, and 61% in interference with daily activities. The control APA group experienced some moderate reduction in these symptoms. Conclusion: Given that this was a pilot study with a small sample size, results must be interpreted with caution. Implications for Practice: Our results suggest that APA may provide an inexpensive and effective complementary approach for the management of symptom clusters for breast cancer patients, and further study is warranted.
Three models for the dielectric function εx(hν) of AlxGa1−xAs are reviewed. All are based on measured optical constants at discrete compositions. The validity of each model near critical point energies, and otherwise, is evaluated. Only the energy-shift model is appropriate over the entire available spectrum (1.5–6.0 eV), including the band-gap (E0) region.
We used the synthetic estrogen R2858 (moxestrol) and estradiol-17 beta, respectively, to characterize the estrogen receptor in baboon (Papio sp.) aortic or myocardial cytoplasmic and nuclear preparations. We observed regional differences in the cytoplasmic fraction estrogen and progesterone receptor content of aortic arch, thoracic aorta, and abdominal aorta when tissues from either oophorectomized or oophorectomized estradiol-17 beta-treated subjects were compared. The estrogen receptor content was highest in the abdominal aorta and lowest in the aortic arch. In contrast, the cytoplasmic fraction progesterone receptor content was highest in the aortic arch and lowest in the abdominal aorta. The nuclear fraction estrogen receptor could not be demonstrated in preparations from cardiovasculature of oophorectomized female baboons. The use of Silastic implants to administer a physiologic concentration of estradiol-17 beta to oophorectomized female baboons caused a 20% to 50% reduction in cytoplasmic fraction estrogen receptor content, which was quantitatively accounted for by the appearance of estrogen receptor in the corresponding nuclear aortic or myocardial preparation. Estrogen administration caused a 20% to 40% increase in cytoplasmic fraction progesterone receptor content in both myocardium and aorta; however, differences were significant only for abdominal aorta (p less than 0.05). Estradiol-17 beta treatment caused a tenfold increase in uterine cytoplasmic fraction progesterone receptor content in treated as compared to oophorectomized control females, suggesting that baboon cardiovasculature is less sensitive to changes in endogenous estrogen concentration than is uterus. The ability of estradiol-17 beta to affect apparent intracellular distribution of baboon cardiovascular estrogen receptors and to elevate cytoplasmic fraction progesterone receptor content suggests that these estrogen receptors are physiologically functional and indicates that estrogen may directly regulate primate cardiovascular cell function.