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Adipocyte death has been reported in both obese humans and rodents. However, its role in metabolic disorders, including insulin resistance, hepatic steatosis, and inflammation associated with obesity...Full Text Available

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BackgroundObesity is one of the principal causative factors involved in the development of metabolic syndrome. AMP-activated protein kinase (AMPK) is an energy sensor that regulates...Full Text Available

UK PubMed Central (United Kingdom)

Rodent models have been extensively utilized to identify putative human immunotoxicants; however, even when immunotoxicity is established, uncertainty remains whether the effects are predictive of human...Full Text Available

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Background:Nicotine alters auditory event-related potentials (ERPs) in rodents and humans and is an effective treatment for smoking cessation. Less is known about the effects of...Full Text Available

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Mood and anxiety disorders and rodent phenotypic measures modeling these disorders have a strong genetic component. Various assays are used to study the neurobiological basis of fear- and anxiety-related...Full Text Available

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Regular physical activity (PA) decreases the risk of several chronic diseases including some cancers, type II diabetes, obesity, and cardiovascular disease; however, the majority of US adults are not meeting the recommended levels to experience these benefits. To address this public health concern, the underlying mechanisms for behavior change need to be understood, translated and disseminated into appropriately tailored interventions. The Transtheoretical Model (TTM) provides a framework for both the conceptualization and the measurement of behavior change, as well as facilitating promotion strategies that are individualized and easily adapted. The purpose of this manuscript is to present the constructs of the TTM as they relate to PA behavior change. We begin with a brief synopsis of rec...

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Background:Childhood obesity is increasingly being observed with changing lifestyles of families. The magnitude of overweight ranges from 9% to 27.5% and obesity ranges...Full Text Available

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BackgroundThe increasing prevalence of obesity in young women is a major public health concern. Few data are available concerning the epidemiology of malnutrition especially obesity...Full Text Available

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Obesity is characterized by the abnormal or excessive deposition of fat in the adipose tissue. Its consequences go far beyond adverse metabolic effects on health, causing an increase in oxidative stress,...Full Text Available

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Concerns for potential vulnerability to manganese (Mn) neurotoxicity during fetal and neonatal development have been raised due to increased needs for Mn for normal growth, different sources of exposure to Mn, and pharmacokinetic differences between the young and adults. A physiologically based pharmacokinetic (PBPK) model for Mn during human gestation and lactation was developed to predict Mn in fetal and neonatal brain using a parallelogram approach based upon extrapolation across life stages in rats and cross-species extrapolation to humans. Based on the rodent modeling, key physiological processes controlling Mn kinetics during gestation and lactation were incorporated, including alterations in Mn uptake, excretion, tissue-specific distributions, and placental and lactational transfer ...

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The bed nucleus of the stria terminalis (BST) and the medial amygdala (MeA) are anatomically connected sites necessary for chemosensory regulation of social behaviors in rodents. Prairie voles (Microtus ochrogaster) are a valuable model for studying the neural regulation of social behaviors because, unlike many other rodents, they are gregarious, pair bond after copulating, and are biparental. We herein describe sex and species differences in immunoreactivity for tyrosine hydroxylase (TH), the rate-limiting enzyme for catecholamine synthesis, in the BST and MeA. Virgin male prairie voles had a large number of TH-immunoreactive cells in areas analogous to the rat principal nucleus of the BST (pBST) and the posterodorsal medial amygdala (MeAPd). Virgin female prairie voles had far fewer TH-immunoreactive cells in these sites ( approximately 17% of the number of cells as males in the pBST, approximately 35% of the number of ...

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Menopause is characterized by the progressive reduction of estrogens resulting to cessation of menses. It is associated with an increase of cardiovascular risk factors such as hyperglycemia, hypertension, dyslipidemia and of abdominal and/or selective visceral fat mass deposition. Obesity, a modern day epidemic, is promoted by an obesogenic environment that interacts with the genetic background. The result is a positive energy balance materialized by the accumulation of the adipose tissue. This process is marked by great individual variation. Obesity is also associated with the presence of cardiovascular risk factors. In this review, the main pathophysiologic processes for the increase of obesity in menopause and the possible effects of pre-menopausal obesity regarding the cessation of ova...

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We have recently reported that spontaneously hypertensive rats (SHRs) exhibit a deficit in contextual fear conditioning that is specifically reversed by antipsychotic and potentiated by psychostimulants and other manipulations thought to produce schizophrenia-like states in rodents. Based on these findings, we suggested that this deficit in fear conditioning could be used as an experimental model of emotional processing impairments observed in schizophrenia. This strain has also been suggested as a model by which to study attention deficit/hyperactivity disorder (ADHD). Considering that schizophrenia and ADHD are both characterized by poor social function, this study aimed to investigate possible behavioral deficits of SHRs in a social context. Furthermore, we sought to examine the effects...

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In general, rapid morphological change in mammals has been infrequently documented. Examples that do exist are almost exclusively of rodents on islands. Such changes are usually attributed to selective...Full Text Available

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BackgroundNinety-one rodent plague epidemics have occurred in Lianghe county, Yunnan Province, China, between 1990 and 2006. This study aimed to identify predictors for the presence...Full Text Available

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Regulatory agencies currently rely on rodent carcinogenicity bioassay data to predict whether or not a given chemical poses a carcinogenic threat to humans. We argue that it is always more useful to...Full Text Available

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No research has compared expressions of weight bias across different subgroups of obese individuals. This study compared attitudes toward and beliefs about obesity in women with and without binge eating disorder (BED) and examined whether these attitudes are related to psychological factors. Fifty obese women with BED were compared with an age- and body mass index (BMI)-matched group of 50 obese women without BED on a battery of established measures of anti-fat attitudes and beliefs about weight controllability and psychological factors (self-esteem, depression, and eating disorder features). The ageand BMI-matched groups did not differ with respect to beliefs about obesity or attitudes toward obese persons, or in self-esteem or depression. Correlational analyses conducted separately within each group revealed that women with BED who reported more favorable ...

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In a "nutrition transition", the consumption of foods high in fats and sweeteners is increasing throughout the developing world. The transition, implicated in the rapid rise of obesity and diet-related...Full Text Available

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The current obesity pandemic is expected to result in considerable downstream morbidity, mortality and incremental costs to health care systems around the world. The major metabolic complications of...Full Text Available

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Obesity and metabolic syndrome result from excess calorie intake and genetic predisposition and are mechanistically linked to type II diabetes and accelerated body aging; abnormal nutrient and insulin...Full Text Available

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Understanding the pathogenesis of obesity is now more important than ever, given the remarkable world-wide epidemic. This paper explores the potential role of core temperature in energy balance, and...Full Text Available

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Acquired resistance to the action of insulin to stimulate glucose transport in skeletal muscle is associated with obesity and promotes the development of type 2 diabetes. In skeletal muscle,...Full Text Available

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The growing epidemic of juvenile obesity has prompted pediatricians to investigate obesity-related conditions in obese teenagers. We report a clinical case of severe hepatic fibrosis in an adolescent with severe and recent obesity. Because of elevated serum aminotransferase levels, abnormal hepatic ultrasonography and insulin resistance (impaired glucose tolerance), we suspected nonalcoholic steatohepatitis (NASH). Disease activity and fibrosis were confirmed on liver biopsy. Considering the risk of progression toward cirrhosis and its complications, and the pathological liver lesions, we started long-term medical monitoring and drug therapy to control weight loss. At present, although biopsy is the only validated way to establish the diagnosis of NASH, there is no consensus on its indicat...

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Abstract This study examines the relationship between emotional/behavioral difficulties and obesity among US adolescents aged 12-17 using parent-reported data for 11,042 adolescents in the National Health Interview Survey. Obesity was defined as body mass index (BMI) ?sex/age-specific 95th percentile BMI cut-points from the 2000 CDC Growth Charts. Types of emotional/behavioral difficulties were identified using the Strengths and Difficulties Questionnaire. Among females, emotional/behavioral difficulties were associated with obesity among non-Hispanic (NH) white and Hispanic adolescents (both those with interviews in English and interviews in Spanish). Among males, emotional/behavioral difficulties were associated with obesity among NH white adolescents and Hispanic males with interview...

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Reports in humans and rodents indicate that immune development may be altered following perinatal exposure to immunotoxic compounds, including chemotherapeutics, corticosteroids, polycyclic hydrocarbons,...Full Text Available

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Lethal yellow (A{sup y}) is a mutation at the mouse agouti locus in chromosome 2 that causes a number of dominant pleiotropic effects, including a completely yellow coat color, obesity, an insulin-resistant type II diabetic condition, and an increased propensity to develop a variety of spontaneous and induced tumors. Additionally, homozygosity for A{sup y} results in preimplantation lethality, which terminates development by the blastocyst stage. The A{sup y} mutation is the result of a 170-kb deletion that removes all but the promoter and noncoding first exon of another gene called Raly, which lies in the same transcriptional orientation as agouti and maps 280 kb proximal to the 3{prime} end of the agouti gene. The authors present a model for the structure of the A{sub y} allele that can explain the dominant pleiotropic effects associated with this mutation, as well as the recessive lethality, which is unrelated to the agouti gene.

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The ability of Yersinia pestis to forestall the mammalian innate immune response is a fundamental aspect of plague pathogenesis. In this study, we examined the effect of Ail, a 17-kDa outer membrane protein that protects Y. pestis against complement-mediated lysis, on bubonic plague pathogenesis in mice and rats. The Y. pestis ail mutant was attenuated for virulence in both rodent models. The attenuation was greater in rats than in mice, which correlates with the ability of normal rat serum, but not mouse serum, to kill ail-negative Y. pestis in vitro. Intradermal infection with the ail mutant resulted in an atypical, subacute form of bubonic plague associated with extensive recruitment of polymorphonuclear leukocytes (PMN or neutrophils) to the site of infection in the draining lymph node and the formation of large purulent abscesses that contained the bacteria. Systemic spread and mortality were greatly attenuated, however, and a productive ...

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IntroductionCopper(II)-diacetyl-bis(N4-methylthiosemicarbazone), or Cu-ATSM, a hypoxia imaging agent, has been shown to be predictive of response to traditional cancer therapies in patients with a wide range of tumors. It is known that the environment of the tumor results in a myriad of physiological consequences, including hypoxia, alterations in metabolism and proliferation. In an effort to better characterize the relationships between Cu-ATSM and other prominent radiopharmaceuticals, this current study was undertaken to compare the regional distribution of 64Cu-ATSM with [18F]fluoromisonidazole (18F-FMISO), [18F]fluoro-2-deoxy-d-glucose (18F-FDG) and [18F]fluorothymidine (18F-FLT) in 9L tumors.MethodsTaking advantage of the different half-life of 18F (t1/2=110 min) in comparison to 64Cu...

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The central nervous system (CNS), generally accepted to regulate energy homeostasis, has been implicated in the metabolic perturbations that either cause or are associated with obesity. Normally, the CNS receives hormonal, metabolic, and neuronal input to assure adequate energy levels and maintain stable energy homeostasis. Recent evidence also supports that the CNS uses these same inputs to regulate glucose homeostasis and this aspect of CNS regulation also becomes impaired in the face of dietary-induced obesity. This review focuses on the literature surrounding hypothalamic regulation of energy and glucose homeostasis and discusses how dysregulation of this system may contribute to obesity and T2DM.

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... estrogen receptor status. Cancer Lett., 253, 291-300. 39. Xin,X ... and resistant mice. Brain Res.Bull., 52, 235-242. 40. Foster,BA ...

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... for a stapling or division of tissue the creation of a small gastric pouch which then assists ... follow up. Laparoscopic gastric bypass entails the surgical creation of a small gastric pouch, typically about an ...

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Adipose tissue plays an essential role in energy homeostasis as a metabolic and endocrine organ. Accordingly, adipocytes are emerging as a major drug target for obesity and obesity-mediated metabolic syndrome. Dysfunction of enlarged adipocytes in obesity is involved in obesity-mediated metabolic syndrome. Adipocytokines, such as adiponectin released from small adipocytes, are able to prevent these disorders. In this study, we found that honokiol, an ingredient of Magnolia officinalis used in traditional Chinese and Japanese medicines, enhanced adipocyte differentiation in 3T3-L1 preadipocytes. Oil Red O staining showed that treatment with honokiol in the presence of insulin dose-dependently increased lipid accumulation in 3T3-L1 preadipoyctes although its activity was weak compared with r...

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diet and genetic obesity metabolic defects and inflammation. To determine the role of adipocyte death in promoting adipose tissue inflammation and insulin resistance in animal...

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In male rodents, anogenital distance (AGD) provides a sensitive and continuous correlate of androgen exposure in the intrauterine environment and predicts later reproductive success. Some endocrine-disrupting chemicals can alter male reproductive tract development, including shortening AGD, in both rodents and humans. Whether AGD is related to semen quality in human is unknown.

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Gonadal hormones modulate neurogenesis in the dentate gyrus differentially in male and female adult rodents. Neurogenesis is comprised of at least two components: cell proliferation (the production of new cells) and cell survival (the number of new neurons that survive to maturity). Previous studies have found sex differences in the level of cell proliferation in the dentate gyrus only when comparing females in a high estrogen state to males. This review focuses on the effects of acute and chronic levels of estrogens or androgens on hippocampal neurogenesis in the adult male and female rodent. Evidence is also reviewed for the co-localization of androgen receptors and estrogen receptors (ER) with markers for cell proliferation or immature new cell survival. Briefly, evidence suggests that ...

UK PubMed Central (United Kingdom)

This study was undertaken to determine which rodent species serve as primary reservoirs for the Lyme disease spirochete Borrelia burgdorferi in commonly occurring woodland types...Full Text Available

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Studies in rodents have shown that male sexual function can be disrupted by fetal or neonatal administration of compounds that alter endocrine homeostasis, such as the synthetic nonsteroidal estrogen...Full Text Available

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Physical activity is associated with reduced risk of several age-related diseases as well as with increased longevity in both rodents and humans. Though these associations are well established, evidence...Full Text Available

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Sexual behavior is a natural reward for many rodent species, and it often includes chemosensory-directed components. Chemosensory stimuli themselves may also be rewarding. Conditioned place...Full Text Available

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1. Interactions of pyrazole and ethanol were studied in three laboratory test procedures. They included sleeping time in mice, rotor rod balance in rats and lever pressing behaviour of rats. 2....Full Text Available

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The destiny of the mitotically active cells of the subventricular zone (SVZ) in adult rodents is to migrate to the olfactory bulb, where they contribute to the replacement of granular and periglomerular...Full Text Available

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The administration of chemicals at the maximum tolerated dose (MTD) in standard animal cancer tests is postulated to increase cell division (mitogenesis), which in turn increases rates of mutagenesis...Full Text Available

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In multiple sclerosis (MS), oligodendrocyte and myelin destruction lead to demyelination with subsequent axonal loss. Experimental demyelination in rodents has highlighted the activation of the subventricular...Full Text Available

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Total potassium was assayed in 150 normal weight and obese females (cervical carcinoma-52, endometrial carcinoma-25 and breast cancer-73) by measurements of 40K spontaneous radiation in a low-background chamber. Control group included 30 healthy and 25 obese females. Computations of body cell and extracellular mass and fat were carried out on the basis of the said measurements. Extracellular fluid volume was measured in 38 patients by X-ray fluorescence method using sodium bromide. The results pointed to a body cell mass deficit matched by increased extracellular mass due to a higher fat level in patients with breast, endometrial and cervical carcinoma. The said correlation was particularly pronounced in obese patients. The beneficial effect of treatment was more often observed in patients with normal body weight. PMID:3739295

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Objectives: Evaluate the effect of diet, physical exercise, and a daily oral intake of a soy isoflavones extract (Fisiogen) contained 200mg of Glycine max, which corresponded to 80mg of isoflavone (60.8mg of genistein, 16mg of daidzein and 3.2mg of glicitein) on leptin and other adipokines plasma levels in healthy obese postmenopausal women. Methods: A multicentric randomized longitudinal prospective cohort study was conducted in a sample of 87 healthy obese postmenopausal women. Patients were randomly assigned to a 1200kcal diet and exercise group (control group) or a group of 1200kcal diet, exercise, and daily oral intake of daily oral intake of a soy isoflavones extract (Fisiogen) contained 200mg of Glycine max, which corresponded to 80mg of isoflavone (60.8mg of genistein, 16mg of daid...

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pD10 is a 0.85 kb fragment with BamHI ends cloned in pSP64. It was sub-cloned from {lambda}D10 which was isolated from a genomic library constructed in {lambda}EMBL3 from a rodent human somatic cell hybrid. The probe was localized to 19q13.2-19qter on a panel of rodent human somatic cell hybrids. Co-dominant segregation was shown in 32 families of 280 individuals.

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Syndrome X is a combination or co-occurrence of several known cardiovascular risk factors (including central obesity, dyslipidemias, fatty liver disease, hyperinsulinemia, insulin resistance,...Full Text Available

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BackgroundLarge population growth surveys of children and adolescents aged 6 to 18 y were undertaken in Hong Kong in 1963 and 1993. The global epidemic of obesity is a major public...Full Text Available

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Percutaneous tracheostomy is a routine procedure in intensive care units. In cases of very low position of the larynx, cervical spine deformation, morbid obesity, or neck tumor, performance of the classic...Full Text Available

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Abnormal fat metabolism plays an important role in the pathogenesis of obesity-related type 2 diabetes mellitus. This study examined whether free fatty acid levels (FFAs), like insulin levels, oscillate...Full Text Available

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BackgroundHealthcare professionals can play a crucial role in optimizing the health status of patients with cardiovascular risk factors (abdominal obesity, high blood pressure, low...Full Text Available

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OBJECTIVENicotinamide adenine dinucleotides (NAD⁺ and NADH) play a crucial role in cellular energy metabolism, and a dysregulated NAD⁺-to-NADH ratio is implicated...Full Text Available

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OBJECTIVE—Identification of arterial genes and pathways altered in obesity and diabetes.RESEARCH DESIGN AND METHODS—Aortic gene expression profiles of...Full Text Available

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The mammalian circadian system consists of a central oscillator in the suprachiasmatic nucleus of the hypothalamus, which coordinates peripheral clocks in organs throughout the body. Although circadian...Full Text Available

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Cellular hypertrophy is regulated by coordinated pro- and antigrowth machineries. Foxo transcription factors initiate an atrophy-related gene program to counter hypertrophic growth. This study was designed...Full Text Available

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Obesity is a risk factor for stroke and neurodegenerative disease. Excess body fat has been linked to impaired glucose metabolism, insulin resistance, and impulsivity and may be a precursor to decline...Full Text Available

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Social stress is prevalent in many facets of modern society. Epidemiological data suggest that stress is linked to the development of overweight, obesity and metabolic disease. Although there...Full Text Available

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OBJECTIVEPhosphoinositide 3-kinase enhancer A (PIKE-A) is a proto-oncogene that promotes tumor growth and transformation by enhancing Akt activity. However, the physiological functions...Full Text Available

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Growing evidences indicate that proteases are implicated in adipogenesis and in the onset of obesity. We previously reported that the cysteine protease cathepsin K (ctsk) is overexpressed in the white...Full Text Available

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BackgroundHigh intake of sugar-sweetened beverages in childhood is linked to increased risk of obesity and type II diabetes later in life. Using three nationally representative surveys...Full Text Available

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ObjectiveMaintaining weight loss is a major challenge in obesity treatment. Individuals often indicate that waning motivation prompts cessation of effective weight...Full Text Available

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The relationship between plasma testosterone levels and locomotor activity in wild-caught sexually mature male meadow voles (Microtus pennsylvanicus) was assessed in the laboratory. Several aspects of locomotor activity were monitored for 1 h on two consecutive days using the automated Digiscan activity monitoring system. Plasma testosterone levels were determined immediately following the second day of activity monitoring. Significant Pearson correlations were obtained between plasma testosterone levels and total distance traveled [r(10) = 0.55, p < 0.05] and amount of time spent in movement [r(10) - 0.55, p < 0.05] on the second day. The wild voles showed a reduction in activity levels from the first to the second day of activity monitoring, which is indicative of habituation to a novel environment. This study provides direct evidence for a significant correlation between laboratory measures of behavioral activity and plasma testosterone levels in a wild-caught ...

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Bariatric surgical procedures have become important therapeutic options for treatment of morbid obesity in both adults and adolescents co-morbidities of obesity such as glucose intolerance, type 2 diabetes (T2DM), metabolic syndrome, steatohepatitis, hyperlipidemia and cardiovascular disease. These co-morbidities of obesity have significant impacts on the overall quality of life of the individual and our society at large. Roux-en-Y gastric bypass (RYGB) and the relatively newer procedures of gastric banding (GB) and vertical sleeve gastrectomy (VSG) have proven to be efficacious in achieving rapid weight loss and reversing the comorbidities of obesity. Unfortunately, bariatric procedures are not without risks including micronutrient deficiency, failure to maintain lost weight, and mortality. Further, the resolution of T2DM has long been understood to precede weight loss, and this finding provides ...

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Breast cancer progression is characterized by inappropriate cell growth. Normal cells cease growth after a limited number of cell divisions--a process called cellular senescence-while tumor cells may acquire the ability to proliferate indefinitely (immortality). Inappropriate expression of specific oncogenes in a key cellular signaling pathway (Ras, Raf) can promote tumorigenicity in immortal cells, while causing finite lifespan cells to undergo a rapid senescence-like arrest. We have studied when in the course of transformation of cultured human mammary epithelial cells (HMEC), the response to overexpressed oncogenic Raf changes from being tumor-suppressive to tumor enhancing, and what are the molecular underpinnings of this response. Our data indicate: (1) HMEC acquire the ability to maintain growth in the presence of oncogenic Raf not simply as a consequence of overcoming senescence, but as a result of a newly discovered step in the process of immortal transformation uncovered by ...

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Inhibition of adipogenesis and lipid accumulation has a very crucial role to prevent obesity. Low molecular weight (LMW) chitosan is known to inhibit fat accumulation and adipogenesis. (N,O)-sulfated chitosan is a sulfation derivative of chitosan oligomers, and its anti-obesity effect is not yet reported. In this study, it has been reported that (N,O)-sulfated chitosan significantly decreased lipid accumulation, an indicator for adipogenesis, in differentiating 3T3-L1 preadipocyte cells. Furthermore, mRNA expressions and protein levels of key adipogenic markers such as peroxisome prolifetor-activated receptor (PPAR)-@c and CCAAT-enhancer binding protein (C/EBP)-@a were considerably decreased by (N,O)-sulfated chitosan treatment. As a consequence, sulfation of LMWC remarkably increased its ...

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Apelin is a peptide known as the ligand of the G-protein-coupled receptor APJ. Several active apelin forms exist such as apelin-36, apelin-17, apelin-13, and the pyroglutamated form of apelin-13. Apelin and APJ are expressed in the central nervous system, particularly in the hypothalamus and in many peripheral tissues. Apelin has been shown to be involved in the regulation of cardiovascular and fluid homeostasis, food intake, cell proliferation, and angiogenesis. In addition to be an ubiquitous peptide, apelin is also produced and secreted by adipocytes and thus considered as an adipokine. This has opened a new field of investigation establishing a link between apelin and metabolic disorders (obesity, type 2 diabetes, etc.) which is the focus of the present review. Several studies, but not...

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In many rodent species, such as Syrian hamsters, reproductive behavior requires neural integration of chemosensory information and steroid hormone cues. The medial amygdala processes both of...Full Text Available

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BackgroundAdipokines, e.g. TNFα, IL-6 and leptin increase insulin resistance, and consequent hyperinsulinaemia influences breast cancer progression. Beside its mitogenic...Full Text Available

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Non-alcoholic fatty liver disease is a serious health problem linked to obesity and type 2 diabetes. To investigate the biological outcome and therapeutic potential of hepatic fatty acid uptake inhibition,...Full Text Available

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The CCAAT/enhancer-binding protein β (C/EBPβ) is required for adipocyte differentiation and maturation. We have studied the role of the transcription factor, C/EBPβ,...Full Text Available

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Comparative sequence analysis of the human and the pufferfish Fugu rubripes (fugu) genomes has revealed several novel functional coding and noncoding regions in the human genome. In particular, the fugu genome has been extremely valuable for identifying transcriptional regulatory elements in human loci harboring unusually high levels of evolutionary conservation to rodent genomes. In such regions, the large evolutionary distance between human and fishes provides an additional filter through which functional noncoding elements can be detected with high efficiency.

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Some of the known toxic effects of lead in mammals including man are, impaired heme synthesis, anemia, nepatopathy, nephropathy, behavioral disorders and neuropathy. However, very little is known about the effect of lead on endocrine physiology. Some data are available on lead induced impairment of thyroid function in occupationally exposed men and experimental rats. As lead nitrate is largely consumed through water and food, in this study the wild rodents Funambulus pennanti were administered lead through their drinking water and their thyroid structure, radioiodine 131-I percentage uptake and protein bound iodine (PBI) level were assessed.

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A combination of sustained release (SR) naltrexone (32mg/day) and bupropion SR (360mg/day) plus behavioral counseling was evaluated for the treatment of smoking cessation and mitigation of nicotine withdrawal and weight gain. Thirty overweight or obese nicotine-dependent subjects were enrolled in a 24-week, open-label study; 85% and 63% completed 12 and 24weeks, respectively. The target quit date was Week 4. Week 4-12 continuous abstinence rate was 48%, 78% of subjects achieved CO 10ppm, serum cotinine decreased from 185 to 48mg/L, and tobacco use decreased from 129 to 14 cigarettes/week. Similar results were seen at Week 24. Body weight was essentially unchanged (Week 12: -0.1%; Week 24: +0.4%). Except for a transient significant increase 1week after the target quit date (p<0.05), nicotin...

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Background This report describes the authors? experience with a unique endoluminal, endoscopically delivered and retrieved gastroduodenojejunal bypass sleeve, including short-term weight loss and changes in comorbidities. Methods A prospective, single-center trial was designed. The patients were morbidly obese individuals who met the National Institutes of Health criteria for bariatric surgery. The device used was a unique gastroduodenojejunal bypass sleeve secured at the esophagogastric junction with endoscopic and laparoscopic techniques and designed to create an endoluminal gastroduodenojejunal bypass. At completion of the trial, the device was explanted with endoscopic retrieval. The primary end points were safety and incidence of adverse events. The secondary outcomes included the per...

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The mammalian placenta consists of different trophoblast cell types that assist in the variety of functions required for the maintenance of pregnancy. In rodents, labyrinthine trophoblasts of the placenta are especially important, because they are capable of differentiating into fused labyrinthine cells, which form the feto-maternal exchange surface. Even though the molecular signals triggering labyrinthine trophoblast differentiation are poorly understood, transforming growth factor-b (TGF-b) has been shown to be present in the placental environment and alter trophoblast development. In this study, we investigated the effects of TGF-b on the differentiation of the labyrinthine trophoblast stem cell lines SM10 and HRP-1. RT-PCR analyses demonstrated that while the molecular expression of l...

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The effects of repeated low-level nerve agent exposure on animal performance and lethality are a major concern of USAF Medical Research. This concern has generated interest in the role that pretreatment drugs such as pyridostigmine may play during simultaneous exposure to soman. This role was investigated by recording lethality, weights, symptoms, and cholinesterase (ChE) inhibition in rats chronically exposed to 4 levels of soman (32, 39, 48 or 59 micrograms/kg/day) while simultaneously receiving 10.0 milligrams/kg/day pyridostigmine, 1.0 milligrams/kg/day pyridostigmine, or vehicle via an osmotic pump. No effect (either protective or detractive) was found in the soman-poisoned animals due to the presence or absence of pyridostigmine. However, rat blood biochemistry is different from that of the primate, warranting further study in the primate before extrapolation to man.

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Health risks associated with inhalation of mineral dusts have been identified to a great extent through epidemiology studies, but also have been assessed by conducting subchronic and chronic inhalation studies typically on rodents. However, in vivo studies are softly, time-consuming, requiring complex technologies, and may not yield information on cellular and molecular mechanisms of response. As a result, the use of in vitro cell culture systems has played an important role in studying the toxicology of mineral dusts and providing insight into action mechanisms. This article reviews selected in vitro approaches that are used to investigate the cytotoxic and inflammatory properties of mineral particles and fibers. In addition key findings as they relate to understanding the toxicology of mineral dusts are presented. 165 refs., 1 fig., 5 tab.

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Many hoarding rodents use burrows not only for dwelling and protection from natural enemies, but also for food storage. However, little is known how burrows used by scatter-hoarding animals influence their foraging behaviors. In addition, handling time for a given food item has a fundamental impact on hoarding strategies of these hoarding animals: food items with longer handling time are more likely to be hoarded due to increasing predation risk because the animals spend more time outside their burrows if they consumed such food. By providing with two types of artificial burrows (aboveground vs. underground) and two types of food items (i.e. seeds) with contrasting handling times, we investigated how burrow condition and handling time co-influence hoarding strategies of a key scatter-hoard...

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We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro.

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This study reports the outcome of real-time ultrasonographic screening tests of a healthy population. The study group consisted of 33 female teachers who were found to have asymptomatic gallstone disease. All cases were followed up to determine the incidence of biliary colic or complications. After a 38-month period of follow-up, seven subjects (21.2%) developed either biliary colic or complication. Study results revealed that the 38-month cumulative probability of the development of biliary colic or complication was 36%. Data shown that development of biliary colic or complications was positively associated with obesity, but no assocition was found with age, number of activities, or duration of contraceptive pill-taking. Having such a high percentage of subjects who developed biliary colic or complications within a relatively short period of time suggests that the silent gallstone is not innocent. PMID:17372404

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A wide variety of phytochemicals present in our diet, including fruits, vegetables, and spices, have been shown to possess a broad range of health-beneficial properties. The cytoprotective and restorative effects of dietary phytochemicals are likely to result from the modulation of several distinct cellular signal transduction pathways. Many dietary phytochemicals that are synthesized as secondary metabolites function as toxins, that is, -phytoalexins,- and hence protect plants against insects and other damaging organisms and stresses. However, at the relatively low doses consumed by humans and other mammals, these same toxic plant-derived chemicals, as mild stressors, activate adaptive cellular response signaling, conferring stress resistance and other health benefits. This phenomenon has...

British Library Electronic Table of Contents (United Kingdom)

Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot ...

Energy Technology Data Exchange (ETDEWEB)

The murine 3T3-L1 fibroblast under appropriate incubation conditions differentiates into an adipocyte phenotype. This 3T3-L1 adipocyte exhibits many of the morphologic, biochemical, and insulin-responsive features of the normal rodent adipocyte. Using quantitative electron microscopic (EM) autoradiography we find that, when /sup 125/I-insulin is incubated with 3T3-L1 adipocytes, the ligand at early times of incubation localizes to the plasma membrane of the cell preferentially to microvilli and coated pits. When the incubation is continued at 37 degrees C, /sup 125/I-insulin is internalized by the cells and preferential binding to the villous surface is lost. With the internalization of the ligand, two intracellular structures become labeled, as determined by the method of hypothetical grain analysis. These include large clear, presumably endocytotic, vesicles and multivesicular bodies. Over the first hour of incubation the labeling of these structures increases in ...

International Nuclear Information System (INIS)

Metabolism of benzene is thought to be necessary to produce the toxic effects, including carcinogenicity, associated with benzene exposure. To extrapolate from the results of rodent studies to potential health risks in man, one must know how benzene metabolism is affected by species, dose, dose rate, and repeated versus single exposures. The purpose of our studies was to determine the effect of repeated inhalation exposures on the metabolism of [14C]benzene by rodents. Benzene metabolism was assessed by characterizing and quantitating urinary metabolites, and by quantitating 14C bound to hemoglobin and micronuclei induction. F344/N rats and B6C3F1 mice were exposed, nose-only, to 600 ppm benzene or to air (control) for 6 hr/day, 5 days/week for 3 weeks. On the last day, both benzene-pretreated and control animals were exposed to 600 ppm, 14C-labeled benzene for 6 hr. Individual benzene metabolites in urine collected for 24 hr after the exposure ...

Scientific Electronic Library Online (English)

Abstract in english In order to evaluate the presence of specific IgG antibodies to Borrelia burgdorferi in patients with clinical manifestations associated with Lyme borreliosis in Cali, Colombia, 20 serum samples from patients with dermatologic signs, one cerebrospinal fluid (CSF) sample from a patient with chronic neurologic and arthritic manifestations, and twelve serum samples from individuals without clinical signs associated with Lyme borreliosis were analyzed by IgG Western blot. The (more) results were interpreted following the recommendations of the Centers for Diseases Control and Prevention (CDC) for IgG Western blots. Four samples fulfilled the CDC criteria: two serum specimens from patients with morphea (localized scleroderma), the CSF from the patient with neurologic and arthritic manifestations, and one of the controls. Interpretation of positive serology for Lyme disease in non-endemic countries must be cautious. However these results suggest that the putative ...

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Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression ...

International Nuclear Information System (INIS)

Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is concluded that animal age influences the degree of photoprotection provided by ...

British Library Electronic Table of Contents (United Kingdom)

Introduction: We have evaluated the ability of a semi-automated, optomotor reflex method to assess drug-induced visual dysfunction, in albino and pigmented rats and mice. Methods: Male Han Wistar (HW) and Long Evans (LE) rats and mice (CD-1 and C57BL/6) were tested in a chamber formed by 4 computer monitors displaying a rotating vertical grating, to elicit head-tracking movements. The highest visible grating frequency was taken as the threshold of visual acuity, in cycles per degree (c/d). Animals received an intravenous infusion of either sodium iodate (50mg/kg) or 0.9% w/v NaCl (aq). They were tested 2h later, then re-tested daily for a further 3days. The time course of the effect was assessed in HW rats over a 6-week period, including electron microscopy, and immunohistochemical analysi...

International Nuclear Information System (INIS)

Two sup(99m)Tc complexes of (N-piperidinylethyl) hexamethyl diaminodithiol (NEP-DADT) have shown high brain uptake in rodents and lower primates. One of these sup(99m)Tc complexes has given positive images of the brain in man which are qualitatively related to regional brain blood flow (rCBF). In order to determine the structure of these sup(99m)Tc products, the corresponding "9"9Tc(NEP-DADT) complexes were prepared and characterized by HPLC, TLC, fast-atom-bombardment mass spectrometry (FAB MS) and other analytical techniques. These results indicate that the two "9"9Tc (NEP-DADT) complexes are syn and anti isomers (i.e. one isomer has the N-piperdinylethyl side chain located syn to the technetium oxo core while the other has this side chain located anti to the technetium oxo core). (author).

International Nuclear Information System (INIS)

When total mesorectal excision (TME) is accurately performed, dysfunction, theoretically, does not occur. However, there are differences among individuals in the running patterns and the volumes of nerve fibers, and if obesity or a narrow pelvis is present, nerve identification is difficult. Currently, the rate of urinary dysfunction after rectal surgery ranges from 33% to 70%. Many factors other than nerve preservation play a role in minor incontinence. Male sexual function shows impotence rates ranging from 20% to 46%, while 20%-60% of potent patients are unable to ejaculate. In women, information on sexual function is not easily obtained, and there are more unknown aspects than in men. As urinary, sexual, and defecation dysfunction due to adjuvant radiotherapy have been reported to occur at a high frequency, the creation of a protocol that enables analysis of long-term functional outcome will be essential for future clinical trials. In the treatment of rectal ...

CERN Document Server

Statistical modelling for social researchers

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

UK PubMed Central (United Kingdom)

The Cox proportional hazards model is the most widely used model for survival analysis because of its simplicity. The fundamental assumption in this model is the proportionality of the hazard function....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

Testosterone has bipotential effects on male fitness; that is, it both suppresses immune function and maintains characteristics important for reproductive success. Presumably, these effects of testosterone may be more pronounced among polygynous species because testosterone concentrations are generally higher among polygynous than monogamous males. The present study examined sex and species differences in cell-mediated immunity among four arvicoline rodents. The role of mating system and sex steroids in sex differences in immune function was examined in individually housed polygynous meadow (Microtus pennsylvanicus) and montane (M. montanus) voles and monogamous prairie (M. ochrogaster) and pine (M. pinetorum) voles in Experiment 1. No sex differences in splenocyte proliferation were observed among the four species and circulating testosterone concentrations did not correlate with immune function of individuals within each species. The contribution of social ...

Science.gov (United States)

Objectives: We have previously shown that chronic exposure to ambient fine particulate matter (less than 2.5 ?m in aerodynamic diameter, PM(2.5)) pollution in conjunction with high-fat diet induces insulin resistance through alterations in inflammatory pathways. In this study we evaluated the effects of PM(2.5) exposure over a substantive duration of a rodent's lifespan and focused on the impact of long-term exposure on adipose structure and function.Methods and Results: C57BL/6 mice were exposed to PM(2.5) or filtered air (FA) (6 hours/day, 5 days/week) for duration of 10 months in Columbus, OH. At the end of the exposure, PM(2.5)-exposed mice demonstrated insulin resistance (IR) and a decrease in glucose tolerance compared with the FA-exposed group. Although there were no significant differences in circulating cytokines between PM(2.5)- and FA-exposed groups, circulating adiponectin and leptin were significantly decreased in PM(2.5)-exposed group. PM(2.5) ...

Science.gov (United States)

This study investigated whether estradiol influenced the survival of new granule neurons, independent of altering cell proliferation, in the adult rodent dentate gyrus and whether estradiol-induced changes in new neuron number relate to any observed changes in hippocampus-dependent behavior. To test whether estradiol specifically promotes the survival of new neurons we injected castrated adult male meadow voles with the cell synthesis marker bromodeoxyuridine (BrdU; 50 mg/kg) twice on day 0 and then injected either estradiol (10 microg) or vehicle for 5 consecutive days either over days 1-5, days 6-10 or days 11-15 and perfused them on day 16. Estradiol doubled the number of hippocampal BrdU-labeled neurons but only when administered during a discrete period (days 6-10; P< or =0.01) when most new neurons extend their axons [J Comp Neurol 413 (1999) 146]. To test whether the estradiol-induced increase in new neuron number was related to hippocampus-dependent ...

International Nuclear Information System (INIS)

Endocrine disrupting chemicals can induce malformations and impairment of reproductive function in experimental animals and may have similar effects in humans. Recently, the environmental obesogen hypothesis was proposed, suggesting that environmental chemicals contribute to the development of obesity and insulin resistance. These effects could be related to chemical interaction with nuclear receptors such as the peroxisome proliferator activated receptors (PPARs). As several testosterone-reducing drugs are PPAR activators, we aimed to examine whether four PPAR agonists were able to affect fetal testosterone production and masculinization of rats. Additionally, we wished to examine whether these chemicals affected fetal plasma levels of insulin and leptin, which play important roles in the developmental programming of the metabolic system. Pregnant Wistar rats were exposed from gestation day (GD) 7-21 to diisobutyl phthalate (DiBP), butylparaben, ...

Science.gov (United States)

... 4 Joint Committee on Atomic Energy as a Model . . . . . ... Joint Committee on Atomic Energy as a Model ...

Wastenet

Institutional and organizational models ... Review individual centre institutional and organizational models in the light of the tasks to be performed by

Energy Technology Data Exchange (ETDEWEB)

The role of natural enemies in the regulation of populations is one of the major questions facing population ecologists. Simplification have led to two theoretical ways of incorporating the role of natural enemies in single ecological models: diffusion models and patch-type models. The predictions of the models are different because of the way variability is incorporated. Three equations are presented for diffusion models and one for patch models. Since the two types of models apply at different combinations of spatial and temporal scales, the right model(s) to choose for a particular study requires careful assessment. A continuing dialogue between experimentalists and theoreticians will lead to a better understanding of natural systems such as those that occur in biological control.

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Background: Cu-diacetyl-bis(N{sup 4}-methylthiosemicarbazone) [Cu-ATSM], although excellent for oncology applications, may not be suitable for delineating cardiovascular or neurological hypoxia. For this reason, new Cu hypoxia positron emission tomography (PET) imaging agents are being examined to search for a higher selectivity for hypoxic or ischemic tissue at higher oxygen concentrations found in these tissues. Two approaches are to increase alkylation or to replace the sulfur atoms with selenium, resulting in the formation of selenosemicarbazones. Methods: Three {sup 64}Cu-labeled selenosemicarbazone complexes were synthesized and one was screened for hypoxia selectivity in vitro using EMT-6 mouse mammary carcinoma cells. Rodent biodistribution and small animal PET images were obtained from BALB/c mice implanted with EMT-6 tumors. One alkylated thiosemicarbazone was synthesized and examined. Results: Of the three bis(selenosemicarbazone) ligands synthesized and ...

Science.gov (United States)

terms of 11) numerical models, 2D SPH simulations, and analytic models. The 1D model was useful for determining the evolution over very long timescales. ...

UK PubMed Central (United Kingdom)

Models can be useful at many different levels when considering complex issues such as biological control of mosquitoes. At an early stage, exploratory models are valuable in exploring the characteristics...Full Text Available

Science.gov (United States)

Engine model: An engine and governor model adapted from a heavy lift helicopter simulation provides a restistic time delay between aerodynamic rotor ...

CERN Document Server

The Inner Model Hypothesis (IMH) and the Strong Inner Model Hypothesis (SIMH) were introduced by the first author in ``Internal consistency and the inner model hypothesis'', Bulletin of Symbolic Logic, December 2006. In this article we establish some upper and lower bounds for their consistency strength.

Science.gov (United States)

This 1978 annual report contains the results of ''Seismic testing of Wolsung-1 steam generator model'' which was initiated in 1977 as a part of a study on nuclear components testing. Model 78, improved version of Model 77 which did not take into account f...

KoreaScience (Korea)

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CERN Document Server

Multiphase reacting flows

Energy Technology Data Exchange (ETDEWEB)

No abstract available.

Norwegian Open Research Archives (NORA)

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KoreaScience (Korea)

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Norwegian Open Research Archives (NORA)

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Czech Academy of Sciences Repository

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Energy Technology Data Exchange (ETDEWEB)

In recent years the modelling of interannual climate variability has been studied, the atmospheric energy and water cycles, and climate simulations with the ECHAM3 model. In addition, the climate simulations of several models have been compared with special emphasis in the area of northern Europe

Norwegian Open Research Archives (NORA)

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KoreaScience (Korea)

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Science.gov (United States)

processes, we construct a stochastic dynamic model for air- craft counts in ... Also , queueing models for the arrival of aircraft at ... A queueing model has also been used to study ...... Assignment and Aircraft-Sequencing Algorithms in Terminal ...

KoreaScience (Korea)

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This paper presents research work concerning the mathematical modelling of air pollution in the Athens basin. A mathematical model based on aerodynamics and conservation equations together with turbulence modelling in body-fitted coordinates is used to provide the necessary input information to a similar but more detailed (i.e. small scale) model around Athens. Both models consist of solving the full Navier-Stokes equations and take into account the precise topography of the region. Different roughness heights are used for sea, coastal regions and land. The smaller scale model makes use of a two-equation turbulence model ({kappa}-{epsilon}) and the large scale model assumes a constant turbulence viscosity. The pollutant sources used in these models are based on actual emissions in the Athens area and ...

CERN Document Server

This paper presents a model of the dynamics of the wage income distribution.

Science.gov (United States)

... 1]. Results and Discussion A cross section of liquid feed direct borohydride fuel cell model was created and studied. The ...

Science.gov (United States)

... Lincoln Laboratory Distribution Models for Optical Scintillation Due to Atmospheric Turbulence RR Parenti RJ Susiela Group 107 ...

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Non-linear autoregressive Markov regime-switching models are intuitive. Time-series approaches for the modelling of electricity spot prices are frequently proposed. In this paper, such models are compared with an ordinary linear autoregressive model with regard to their forecast performances. The study is carried out using German daily spot-prices from the European Energy Exchange in Leipzig. Four non-linear models are used for the forecast study. The results of the study suggest that Markov regime-switching models provide better forecasts than linear models. (author)

Science.gov (United States)

... 3 Joint Committee on Atomic Energy as a Model . . . . . ... Joint Committee on Atomic Energy as a Model Page 8. CRS-4 ...

CERN Document Server

The concept of frailty offers a convenient way to introduce unobserved heterogeneity and associations into models for survival data. In its simplest form, frailty is an unobserved random proportionality factor that modifies the hazard function of an individual or a group of related individuals. "Frailty Models in Survival Analysis" presents a comprehensive overview of the fundamental approaches in the area of frailty models. The book extensively explores how univariate frailty models can represent unobserved heterogeneity. It also emphasizes correlated frailty models as extensions of

CERN Document Server

This paper proposes the use of particle swarm optimization method (PSO) for finite element (FE) model updating. The PSO method is compared to the existing methods that use simulated annealing (SA) or genetic algorithms (GA) for FE model for model updating. The proposed method is tested on an unsymmetrical H-shaped structure. It is observed that the proposed method gives updated natural frequencies the most accurate and followed by those given by an updated model that was obtained using the GA and a full FE model. It is also observed that the proposed method gives updated mode shapes that are best correlated to the measured ones, followed by those given by an updated model that was obtained using the SA and a full FE model. Furthermore, it is observed that the PSO achieves this accuracy at a computational speed that is faster than that by the ...

Energy Technology Data Exchange (ETDEWEB)

A detailed component-based simulation model of a geothermal heat pump system has been calibrated to monitored data taken from a family housing unit located at Fort Polk, Louisiana. The simulation model represents the housing unit, geothermal heat pump, ground heat exchanger, thermostat, blower, and ground-loop pump. Each of these component models was tuned to better match the measured data from the site. These tuned models were then interconnected to form the system model. The system model was then exercised in order to demonstrate its capabilities.

British Library Electronic Table of Contents (United Kingdom)

This paper introduces a new way of estimating parameters in a Brownian motion regime switching asset model to incorporate volatility clustering. The regime switching model is then applied to pricing of up-and-in barrier call options. We take the probability of crossing the barrier between simulation points into account, and we increase accuracy in simulations by importance sampling. The regime switching model is compared to the Normal Inverse Gaussian model and the traditional Black-Scholes model, and option prices from the regime switching model are compared to the closed form expression of up-and-in barrier calls in a Black-Scholes market.

International Nuclear Information System (INIS)

An integrated approach to the modelling of hydrogen assisted failure in 316L steel is presented. The approach includes experimental, fractographic, numerical and theoretical analysis of the phenomenon. The physical adequacy of the mechanical models of hydrogen embrittlement (notch extension model and notch cracking model) is discussed by comparing the virtual damage depth (theoretical) predicted by the models with the embrittled zone (microphysical) measured in the fractographic analysis by scanning electron microscopy. In addition, a numerical modelling of hydrogen diffusion is performed, concluding that bulk diffusion is not important in hydrogen embrittlement of 316L steel, so that hydrogen transport accelerated by the microdamage itself should be taken into account. (orig.)

International Nuclear Information System (INIS)

The SMART (System-integrated Modular Advanced ReacTor) which is a 330 MWt advanced integral PWR was developed by the KAERI (Korea Atomic Energy Institute) for electricity generation and seawater desalination. A thermal hydraulic evaluation and analysis of the SMART is performed by the TASS /SMR-S (Transient And Setpoint Simulation/System integrated Modular Reactor-Safety). The TASS/SMR-S code has various models reflecting the design features of the SMART such as the drift flux model, the core models (core power and core heat transfer model), the component models, and the specific models. One of the core models is the core heat transfer model. The role of this model is to calculate the heat flux and radial temperature profiles at a fuel rod surface using the relevant heat transfer correlations for all ...

CERN Document Server

A class of nonlinear models combining a pharmacokinetic compartmental model and a pharmacodynamic Emax model is introduced. The locally D-optimal (LD) design for a four-parameter composed model is found to be a saturated four-point uniform LD design with the two boundary points of the design space in the LD design support. For a five-parameter composed model, a sufficient condition for the LD design to require the minimum number of sampling time points is derived. Robust LD designs are also investigated for both models. It is found that an LD design with $k$ parameters is equivalent to an LD design with $k-1$ parameters if the linear parameter in the two composed models is a nuisance parameter. Assorted examples of LD designs are presented.

Energy Technology Data Exchange (ETDEWEB)

Stylized numerical models of the tooth are usually employed in qualification procedure related to Electronic Paramagnetic Resonance in long-term accidental contamination dose reconstruction. In this work a voxel model was developed from the microCT image data set of a human non contaminated molar tooth. A stylized model, reproducing the characteristics of the voxel model, was also created in order to investigate the level of accuracy that can be obtained in this kind of study.

International Nuclear Information System (INIS)

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

DEFF Research Database (Denmark)

In this paper we present a modeling framework for analyzing computer models with two types of variations. The paper is based on a case study of an orthopedic surgical unit, which has both controllable and uncontrollable factors. Our results show that this structure of variation can be modeled effectively with linear mixed effects models and generalized additive models. Copyright (C) 2009 John Wiley & Sons, Ltd.

CERN Document Server

Tree-level scattering amplitudes of longitudinally polarized electroweak vector bosons in the Standard Model are calculated using Mathematica package Feyncalc. The modifications of low-energy theorems for longitudinally polarized W and Z in the Standard Model are discussed.

Science.gov (United States)

... Results of Source Emissions Testing UTC Fuel Cell Model PC25C ... Results of Source Emissions Testing: UTC Fuel Cell Model PC25C ...

International Nuclear Information System (INIS)

We obtain a symmetry algebra for any unitary minimal model by using the representation of conformal field theories. This symmetry algebra can be interpreted as a quantum group. The generalization to non-unitary minimal models is direct. (orig.).

UK PubMed Central (United Kingdom)

SummaryWe develop a new class of models, dynamic conditionally linear mixed models, for longitudinal data by decomposing the within-subject covariance matrix using a special Cholesky...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The report provides and overview of calculation models for the simulation of airflows and deals comprehensively with field and multi-zone models as well as the coupling of individual zone and multi-zone models. Examples of calculations are given. figs., tabs., refs.

UK PubMed Central (United Kingdom)

A new 3D model is developed to simulate the self-oscillation of the elongated vocal folds. This model allows for large deformation and longitudinal displacement. The displacement boundary condition...Full Text Available

UK PubMed Central (United Kingdom)

New habitat-based models for spread of hantavirus are developed which account for interspecies interaction. Existing habitat-based models do not consider interspecies pathogen transmission,...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Volume VI of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the groundwater flow model data. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

International Nuclear Information System (INIS)

Geochemical model is a kind of concept model which describes geochemical processes by means of chemical reaction equations and mathematical formula, and the software based on the concept model are called geochemical modeling code. Geochemical modeling codes can be divided into three categories: mass equilibrium, mass transfer and mass transport code. The major functions of geochemical codes include the calculation of forms of occurrence of elements, the prediction of direction of various geochemical reaction, the dissolution and precipitation of elements, the pH and Eh value, the rate and path of geochemical reaction in aqueous solution.

Energy Technology Data Exchange (ETDEWEB)

In this letter, they present the results on a global fit to precision electroweak data in a Higgs triplet model. In models with a triplet Higgs boson, a consistent renormalization scheme differs from that of the Standard Model and the global fit shows that a light Higgs boson with mass of 100-200 GeV is preferred. Triplet Higgs bosons arise in many extensions of the Standard Model, including the left-right model and the Little Higgs models. The result demonstrates the importance of the scalar loops when there is a large mass splitting between the heavy scalars. It also indicates the significance of the global fit.

Science.gov (United States)

pletely new PW fuel cell model had to be developed for CINDA. Several ...... following linear equation, which is used in the SINDA fuel cell model: ...

Science.gov (United States)

... 13 2.4 Inertial Navigation Error Model . . . . . ... sources such as electrical noise, thermal noise, etc. 2.4 Inertial Navigation Error Model ...

British Library Electronic Table of Contents (United Kingdom)

Abstract We present a study of the impact of different model groups in the detection of circumstellar debris discs. Almost all previous studies in this field have used kurucz (atlas9) model spectra to predict the stellar contribution to the flux at the wavelength of observation, thus determining the existence of a disc excess. Only recently have other model groups or families like marcs and nextgen (phoenix) become available to the same extent as atlas9. This study aims to determine whether the predicted stellar flux of a disc target can change with the choice of model family can a disc excess be present in the use of one model family whilst being absent from another. A simple comparison of kurucz model spectra with marcs and nextgen model spectra of identical stellar parameters was conduc...

International Nuclear Information System (INIS)

We argue that the tachyons which exist in some string models are a signal of deconfinement. We compare the deconfinement temperature obtained from Monte Carlo calculations with some string models. (orig.).

Energy Technology Data Exchange (ETDEWEB)

A strong necessary condition is given for the principal stabiliser of the action of a compact Lie group to have a non-zero centre. An application to the monopole problem in Yang-Mills-Higgs models is discussed.

Science.gov (United States)

... CycleSim models an IBM PowerPC 405GP system-on-a-chip and includes a cycle-accurate, event-based power model of the processor core and ...

International Nuclear Information System (INIS)

The basic relationships of the convolution/superposition dose calculation technique are reviewed, and a modelling technique that can be used for obtaining a satisfactory beam model for a commercially available convolution/superposition-based treatment planning system is described. A fluence energy spectrum for a Co-60 treatment machine obtained from a Monte Carlo simulation was used for modelling the fluence spectrum for a Rokus M machine. In order to achieve this model we measured the depth dose distribution and the dose profiles with a Wellhofer dosimetry system. The primary fluence was iteratively modelled by comparing the computed depth dose curves and beam profiles with the depth dose curves and crossbeam profiles measured in a water phantom. The objective of beam modelling is to build a model of the primary fluence that the patient is ...

UK PubMed Central (United Kingdom)

In this paper, we suggest that perception could be modeled by assuming that sensory input is generated by a hierarchy of attractors in a dynamic system. We describe a mathematical model which exploits...Full Text Available

Science.gov (United States)

The propeller governor model adjusts propeller pitch, p, in order to provide constant shaft RPM. ... Block Diagram of Propeller Governor Model ...

British Library Electronic Table of Contents (United Kingdom)

A microcosm laboratory experiment was conducted to determine the impact of biological reworking by the ragworm Nereis diversicolor on the redistribution of particle-bound radionuclides deposited at the sediment-water interface. Over the course of the 40-day experiment, as much as 35% of a 137Cs-labelled particulate tracer deposited on the sediment surface was redistributed to depths of up to 11 cm by the polychaete. Three different reworking models were employed to model the profiles and quantify the biodiffusion and biotransport coefficients: a gallery-diffuser model, a continuous sub-surface egestion model and a biodiffusion model. Although the biodiffusion coefficients obtained for each model were quite similar, the continuous sub-surface egestion model provided the best fit to the data...

British Library Electronic Table of Contents (United Kingdom)

The aim of this work is the development and experimental validation of a detailed dynamic fuel cell model using the gPROMS modeling environment. The model is oriented towards optimization and control and it relies on material and energy balances as well as electrochemical equations including semi-empirical equations. For the experimental validation of the model a fully automated and integrated hydrogen fuel cell testing unit was used. The predictive power of the model has been compared with the data obtained during load change experiments. A sensitivity analysis has been employed to reveal the most critical empirical model parameters that should be estimated using a systematic estimation procedure. Model predictions are in good agreement with experimental data under a wide range of operati...

Energy Technology Data Exchange (ETDEWEB)

The present volume on modeling of batteries and fuel cells discusses the significance of the effectiveness factor for flooded porous electrodes, active pore distribution spectroscopy for characterizing porous battery electrodes, the agglomerate model for porous electrodes, and dynamic-performance measurements of battery cells for electric vehicles and other applications. Attention is given to mathematical modeling of a primary zinc/air battery, mathematical modeling of Grace Li-TiS2 cells, modeling of electrocrystallization processes in battery systems, and rotating disk electrode studies in molten Li/K carbonate eutectic. Topics addressed include the variability of nickel oxide cathode dissolution in molten carbonate fuel cells, water transport properties of fuel cell ionomers, modeling water content effects in polymer electrolyte fuel cells, and computer ...

Science.gov (United States)

This paper proposes an approach that mitigates the problem of verification of network security system properties over concurrent processes.

CERN Document Server

In undirected graphical models, learning the graph structure and learning the functions that relate the predictive variables (features) to the responses given the structure are two topics that have been widely investigated in machine learning and statistics. Learning graphical models in two stages will have problems because graph structure may change after considering the features. The main contribution of this paper is the proposed method that learns the graph structure and functions on the graph at the same time. General graphical models with binary outcomes conditioned on predictive variables are proved to be equivalent to multivariate Bernoulli model. The reparameterization of the potential functions in graphical model by conditional log odds ratios in multivariate Bernoulli model offers advantage in the representation of the conditional independence ...

UK PubMed Central (United Kingdom)

An acute exudative Escherichia coli pyelonephritis rat model was used to study the influence of progressive pyelonephritis on the efficacy of antibiotic treatment. In this model, transient ureteral...Full Text Available

Science.gov (United States)

... 2.5.6 Development of Observation Equations . . . . . 25 2.6 Inertial Navigation Error Model . . . . . ... 2 , as expected. 2.6 Inertial Navigation Error Model ...

Science.gov (United States)

note that this form for heat transfer augmentation has apparently never been used with other evaporation models, even though it is a natural extension of ...

Science.gov (United States)

Sep 1, 2011 ... Estimating Travel Cost Model: Spatial Approach. In: Annual Meetings of the American Agricultural Economics Association. ...

UK PubMed Central (United Kingdom)

We develop and investigate numerically a thermodynamically consistent model of two-dimensional multicomponent vesicles in an incompressible viscous fluid. The model is derived using an energy...Full Text Available

CERN Document Server

Model selection aims to determine which theoretical models are most plausible given some data, without necessarily asking about the preferred values of the model parameters. A common model selection question is to ask when new data require introduction of an additional parameter, describing a newly-discovered physical effect. We review several model selection statistics, and then focus on use of the Bayesian evidence, which implements the usual Bayesian analysis framework at the level of models rather than parameters. We describe our CosmoNest code, which is the first computationally-efficient implementation of Bayesian model selection in a cosmological context. We apply it to recent WMAP satellite data, examining the need for a perturbation spectral index differing from the scale-invariant (Harrison-Zel'dovich) case.

UK PubMed Central (United Kingdom)

Introduction:The purpose of this study was to utilize an in vitro biofilm model of subgingival plaque to investigate resistances in subgingival biofilm...Full Text Available

International Nuclear Information System (INIS)

In the safety assessment of a high-level radioactive waste (HLW) disposal system, it is required to estimate radiological impacts on future human beings arising from potential radionuclide releases from a deep repository into the surface environment. In order to estimated the impacts, a biosphere model is developed by reasonably assuming radionuclide migration processes in the surface environment and relevant human lifestyles. It is important to modify the present biosphere models or to develop alternative biosphere models applying the biosphere models according to quality and quantify of the information acquired through the siting process for constructing the repository. In this study, alternative biosphere models were developed taking geosphere-biosphere interface of marine environment into account. Moreover, the flux to dose conversion factors calculated by these alternative ...

Energy Technology Data Exchange (ETDEWEB)

The neutron star parameters in the model extended by the inclusion of {delta} meson and additional nonlinear vector meson interactions are studied.

UK PubMed Central (United Kingdom)

In this model, without dark matter, the flat rotation curves of galaxies and the mass-to-light ratios of clusters of galaxies are described quantitatively. The hypothesis is that the agent of gravitational...Full Text Available

Science.gov (United States)

May 31, 2011 ... A Theoretical Solid Oxide Fuel Cell Model for System Controls and Stability Design AUTHOR(S): Kopasakis, George; Brinson, Thomas; Credle, ...

CERN Document Server

Starting from the Plebanski formulation of gravity as a constrained BF theory we propose a new spin foam model for 4d Riemmanian quantum gravity that generalises the well-known model of Barrett-Crane and resolves the ultralocality problem that this model is known to possess. It is well known that the BF formulation of 4d gravity possesses two sectors: one corresponding to gravity and the other topological. The model presented here is shown to give a quantisation of the gravitational sector. The present model is dual to the recently proposed spin foam model of Engle et al. which, we show, corresponds to the topological sector of the theory. One important outcome of our approach is that it also allow us to introduce the Immirzi parameter into the framework of spin foam quantisation. We generalize some of our considerations to the Lorentzian setting and obtain a ...

Science.gov (United States)

... Accession Number : ADA539720. Title : A Hybrid Kinetic Model of Asymmetric Thin Current Sheets with Sheared Flows in a Collisionless Plasma. ...

Energy Technology Data Exchange (ETDEWEB)

The thesis describes work undertaken as part of a larger remote sensing based project which aims to detect, measure and monitor coal fires in two test areas in northern China. The first main topic addressed in this thesis is the detection of fires using several different thermal remote sensing data sets. The synergistic use of the different data sets is emphasised. The second major part of the thesis deals with thermal modelling of the coal fires. Three different models are developed, which allow a fire's depth, temperature, extent, total heat output and rate of movement to be determined. The models are tested both in the laboratory and using various field data sets. A model based on the assumption that the fire is a point heat source and that the temperature distribution around it is spherically symmetrical is shown to be the most effective. A simpler, one-dimensional coal fire ...

International Nuclear Information System (INIS)

A numerical study of a natural convection in a rectangular cavity with the low-Reynolds-number differential stress and flux model is presented. The primary emphasis of the study is placed on the investigation of the accuracy and numerical stability of the low-Reynolds-number differential stress and flux model for a natural convection problem. The turbulence model considered in the study is that developed by Peeters and Henkes (1992) and further refined by Dol and Hanjalic (2001), and this model is applied to the prediction of a natural convection in a rectangular cavity together with the two-layer model, the shear stress transport model and the time-scale bound #upsilon#"2-f model, all with an algebraic heat flux model. The computed results are compared with the experimental data commonly used for the validation of the ...

CERN Document Server

Warm-intermediate inflationary universe models in the context of braneworld cosmologies, are studied. This study is done in the weak and strong dissipative regimes. We find that, the scalar potentials and dissipation coefficients in terms of the scalar field, evolves as type-power-law and powers of logarithms, respectively. General conditions required for these models to be realizable are derived and discussed. We also study the scalar and tensor perturbations for each regime. We use recent astronomical observations to constraint the parameters appearing in the braneworld models.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

... Descriptors : *QUEUEING THEORY, *APPROXIMATION ... MODELS, OPTIMIZATION, STOCHASTIC PROCESSES ... Categories : TERMINAL FLIGHT ...

KoreaScience (Korea)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Quark-hadron duality and its potential applications are discussed. We focus on theoretical efforts to model duality.

Science.gov (United States)

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KoreaScience (Korea)

Full Text Available

CERN Document Server

We study the dynamics of the scalar tensor cosmological model in the presence of tachyon field. In an alternative approach, in two exponential and power law form of the scalar field functions in the model, field equations are solved by simultaneously best fitting the model parameters with the most recent observational data. This approach gives us an observationally verified interpretation of the dynamics of the universe. We then discuss the best fitted of equation of state parameter, the statefinder parameters and the reconstructed scalar field in the model.

Science.gov (United States)

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Science.gov (United States)

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