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Kinds of Degree Terms modified by Degree Selected AbstractsTHE EVOLUTION OF SPERM-ALLOCATION STRATEGIES AND THE DEGREE OF SPERM COMPETITIONEVOLUTION, Issue 3 2005Paul D. Williams Abstract The prevailing viewpoint in the study of sperm competition is that male sperm-allocation strategies evolve in response to the degree of sperm competition an ejaculate can expect to experience within a given mating. If males cannot assess the degree of sperm competition their ejaculate will face and/or they are unable to facultatively adjust sperm investment in response to perceived levels of competition, high sperm allocation (per mating) is predicted to evolve in the context of high sperm competition. An implicit assumption of the framework used to derive this result is that the degree of sperm competition is unaffected by changes in sperm-allocation strategies. We present theory based on an alternative perspective, in which the degree of sperm competition and the sperm-allocation strategy are coupled traits that coevolve together. Our rationale is that the pattern of sperm allocation in the population will, in part, determine the level of sperm competition by affecting the number of ejaculates per female in the population. In this setting, evolution in sperm-allocation strategies is driven by changes in underlying environmental parameters that influence both the degree of sperm competition and sperm allocation. This change in perspective leads to predictions that are qualitatively different from those of previous theory. [source] A COMPARISON OF FIVE HYBRID ZONES OF THE WETA HEMIDEINA THORACICA (ORTHOPTERA: ANOSTOSTOMATIDAE): DEGREE OF CYTOGENETIC DIFFERENTIATION FAILS TO PREDICT ZONE WIDTHEVOLUTION, Issue 4 2003Mary Morgan-Richards Abstract Tension zones are maintained by the interaction between selection against hybrids and dispersal of individuals. Investigating multiple hybrid zones within a single species provides the opportunity to examine differences in zone structure on a background of differences in extrinsic factors (e.g., age of the zone, ecology) or intrinsic factors (e.g., chromosomes). The New Zealand tree weta Hemideina thoracica comprises at least eight distinct chromosomal races with diploid numbers ranging from 2n = 11 (XO) to 2n = 23 (XO). Five independent hybrid zones were located that involve races differing from one another by a variety of chromosomal rearrangements. The predicted negative correlation between extent of karyotypic differentiation (measured in terms of both percent of genome and number of rearrangements) and zone width was not found. Conversely, the widest zones were those characterized by two chromosome rearrangements involving up to 35% of the genome. The narrowest zone occurred where the two races differ by a single chromosome rearrangement involving approximately 2% of the genome. The five estimates of chromosomal cline width ranged from 0.5 km to 47 km. A comparative investigation of cline width for both chromosomal and mitochondrial markers revealed a complex pattern of zone characteristics. Three of the five zones in this study showed cline concordance for the nuclear and cytoplasmic markers, and at two of the zones the clines were also coincident. Zones with the widest chromosomal clines had the widest mitochondrial DNA clines. It appears that, even within a single species, the extent of karyotypic differentiation between pairs of races is not a good predictor of the level of disadvantage suffered by hybrids. [source] Learning From the Pros: Influence of Web-Based Expert Commentary on Vicarious Learning About Financial Markets,DECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 1 2007Matthew W. Ford ABSTRACT Web-based financial commentary, in which experts routinely express market-related thought processes, is proposed as a means for college students to learn vicariously about financial markets. Undergraduate business school students from a regional university were exposed to expert market commentary from a single financial Web site for a 6-week period. When compared to a control group, students in the experimental group were found to possess higher levels of financial market awareness. Degree of engagement, as approximated by measures of project exposure time and effort, was significantly related to market awareness. Finance majors were found to be more engaged in the process than nonfinance majors. Although this study should be considered exploratory in nature, findings support the notion of using Web-based vicarious learning processes in financial education. Future research can extend the generalizability of these findings, as well as shape vicarious learning mechanisms for use across business disciplines. [source] Intra-individual variability in infancy: Structure, stability, and nutritional correlatesDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2008Theodore D. Wachs Abstract Intra-individual variability (IIV) refers to relatively stable differences between individuals in the degree to which they show behavioral fluctuations over relatively short time periods. Using temperament as a conceptual framework the structure, stability, and biological roots of IIV were assessed over the first year of life. Biological roots were defined by maternal and infant nutrition. The sample was 249 Peruvian neonates, followed from the second trimester of pregnancy through the first 12 months of life. Maternal anthropometry, diet, iron status, and fetal growth were assessed prenatally. Neonatal anthropometry and iron status were assessed at birth. Degree of exclusive breastfeeding was assessed at 3 and 6 months, infant anthropometry was assessed at 3, 6, and 12 months, infant dietary intake was assessed at 6 and 12 months and infant iron status was tested at 12 months. Individual differences in IIV at 3, 6, and 12 months were derived from a residual standard deviation score based on infant behaviors measured using the Louisville Temperament Assessment Procedure. Principal components analysis indicated that individual differences in IIV were defined by two components at 3, 6, and 12 months. There was modest stability between IIV components assessed at 3 and 12 months. Reduced levels of IIV at 3 months were predicted by higher maternal weight and higher fetal weight gains in the first and second trimesters of pregnancy. Higher levels of IIV at 3 months were predicted by higher levels of maternal hemoglobin during pregnancy and higher levels of neonatal ferritin. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 217,231, 2008. [source] Variation among individual butterflies along a generalist,specialist axis: no support for the ,neural constraint' hypothesisECOLOGICAL ENTOMOLOGY, Issue 3 2007BRIAN WEE Abstract 1.,Degree of host specialisation was a continuous variable in a population of Edith's checkerspot butterfly (Euphydryas editha). A novel host, Collinsia torreyi, had been added to the diet in response to anthropogenic disturbance, and then abandoned prior to the current study. Butterflies either showed no preference or preferred their traditional host, Pedicularis semibarbata. 2.,Strength of preference for Pedicularis over Collinsia was measured in the field and used to estimate host specialisation of individual butterflies. Efficiency was estimated from the times taken by each insect to perform two tasks: (i) identification of a Pedicularis plant as a host, and (ii) successful initiation of oviposition after the decision to do so had been made. 3.,There was no clear trend for association between host specialisation and either measure of efficiency. Generalists were not slower than specialists at identifying Pedicularis as a host or at handling it after deciding to oviposit. 4.,Prior work indicated that generalists paid no detectable cost in terms of reduced discrimination among individuals of their preferred host species. 5.,In contrast to other species, generalist E. editha paid in neither time nor accuracy. Why then does the diet not expand? Behavioural adaptations to the traditional host caused maladaptations to the novel host and generated short-term constraints to evolutionary expansion of diet breadth. To date, however, no long-term constraints have been found in this system. In those traits investigated to date, increased adaptation to the novel host has not caused reduced adaptation to the traditional host. [source] The efficacy of dantrolene sodium in controlling exertional rhabdomyolysis in the Thoroughbred racehorseEQUINE VETERINARY JOURNAL, Issue 7 2003J. G. T. Edwards Summary Reasons for performing study: Dantrolene sodium (Dantrium) has been used extensively for the treatment of myopathies in man and anecdotal evidence suggests it is of clinical benefit in the control of exercise-induced rhabdomyolysis (ER) in racehorses, although data to support this are currently lacking. Objectives: To investigate the efficacy of oral dantrolene sodium in controlling ER in a randomised, double-blind, placebo-controlled crossover trial involving 77 Thoroughbred racehorses in Newmarket, UK. Methods: Horses were treated on 2 occasions 1 week apart, with treatment days coinciding with a return to exercise following 2 days box rest on each occasion. For the first treatment, each horse was randomly selected to receive either 800 mg dantrolene sodium or a colour- matched placebo administered orally 1 h before exercise. This was followed by crossover to the other treatment on the second occasion, with each horse thereby acting as its own control. Degree of ER was assessed using rising serum creatine kinase (CK) levels, by subtracting pre-exercise blood CK levels from those measured in 6 h post exercise blood samples. For each horse, the difference in change between pre- and post exercise CK values between placebo and dantrolene treatments was calculated, with positive values indicating a greater rise with placebo than with dantrolene sodium treatment. Results: The overall mean difference for all horses was +104.8 iu/l and the null hypothesis, that there was no true difference in non-normally distributed post exercise rises in CK values between placebo and dantrolene treatments, was rejected (P = 0.0013) using the nonparametric Wilcoxon signed rank test. Additionally, no horses given dantrolene sodium showed clinical signs of ER, whereas 3 horses given the placebo developed ER following exercise. The incidence of ER in the study was 4% (3/77). Conclusions: The results confirmed that oral administration of dantrolene sodium, 1 h before exercise, had a statistically significant effect on reducing the difference between pre - and post exercise plasma CK levels compared with a placebo in the same animals, and preventing clinical ER in susceptible individuals. Potential relevance: This study suggested that dantrolene sodium is of use in controlling ER in the Thoroughbred racehorse. Further investigation into pre- and post exercise myoplasmic calcium levels and the repeat of the study late in the season when horses receive a much higher energy ration and more strenuous exercise would appear to be warranted. [source] Cerebrospinal fluid biomarkers of white matter lesions , cross-sectional results from the LADIS studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2010M. Jonsson Background and purpose:, White matter lesions (WMLs) caused by small vessel disease are common in elderly people and contribute to cognitive impairment. There are no established biochemical markers for WMLs. We aimed to study the relation between degree of WMLs rated on magnetic resonance imaging of the brain and cerebrospinal fluid (CSF) levels of structural biomarkers associated with Alzheimer's disease (AD) and subcortical vascular dementia. Methods:, Fifty-three non-demented elderly individuals with WMLs were subjected to lumbar puncture. Degree of WMLs was rated using the Fazekas scale. Volumetric assessment of WMLs was performed. CSF samples were analyzed for the 40 and 42 amino acid fragments of amyloid ,, ,- and ,-cleaved soluble amyloid precursor protein, total tau (T-tau), hyperphosphorylated tau (P-tau181), neurofilament light protein (NFL), sulfatide and CSF/Serum-albumin ratio. Results:, Fifteen subjects had mild, 23 had moderate and 15 had severe degree of WMLs. CSF-NFL levels differed between the groups (P < 0.001) and correlated with the volume of WMLs (r = 0.477, P < 0.001). CSF sulfatide concentration displayed similar changes but less strongly. T-tau, P-tau181 and the different amyloid markers as well as CSF/S-albumin ratio did not differ significantly between the groups. Conclusions:, The association of increased CSF-NFL levels with increasing severity of WMLs in non-demented subjects suggests that NFL is a marker for axonal damage in response to small vessel disease in the brain. This manifestation may be distinct from or earlier than the neurodegenerative process seen in AD, as reflected by the lack of association between WMLs and AD biomarkers. [source] Degree of conversion and permeability of dental adhesivesEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2005Milena Cadenaro The aim of this study was to analyse the extent of polymerization of different adhesive films in relation to their permeability. One adhesive of each class was investigated: OptiBond FL; One-Step; Clearfil Protect Bond; and Xeno III. Adhesive films were prepared and cured with XL-2500 (3M ESPE) for 20, 40 or 60 s. Polymerization kinetic curves of the adhesives tested were obtained with differential scanning calorimetry (DSC) and data were correlated with microhardness. The permeability of the adhesives under the same experimental conditions was evaluated on human extracted teeth connected to a permeability device and analysed statistically. The results showed that the extent of polymerization obtained from DSC exotherms was directly correlated with microhardness. An increased level of polymerization after prolonged light-curing was confirmed for all adhesives. Simplified adhesives exhibited a lower extent of polymerization and showed incomplete polymerization, even after 60 s. An inverse correlation was found between the degree of cure and the permeability. This study supports the hypothesis that the permeability of simplified adhesives is correlated with incomplete polymerization of resin monomers and the extent of light exposure. These adhesives may be rendered less permeable by using longer curing times than those recommended by the respective manufacturer. [source] Degree of discrepancy between self and other-reported everyday functioning by cognitive status: dementia, mild cognitive impairment, and healthy eldersINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2005Sarah Tomaszewski Farias Abstract Background Previous studies show individuals with dementia overestimate their cognitive and functional abilities compared to reports from caregivers. Few studies have examined whether individuals with Mild Cognitive Impairment (MCI) also tend to underestimate their deficits. In this study we examined whether degree of discrepancy between patient and informant-reported everyday functioning was associated with cognitive status. Methods The sample consisted of 111 ethnically diverse community-dwelling older adults (46 Caucasians and 65 Hispanic individuals), which was divided into four diagnostic categories: cognitively normal, MCI-memory impaired, MCI-nonmemory impaired, and demented. Everyday functional abilities were measured using both a self-report and informant-report version of the Daily Function Questionnaire (DFQ). A Difference Score was calculated by subtracting patients' DFQ score from their informants' score. Results DFQ Difference Scores were significantly higher in the demented group compared to normals and both of the MCI groups. However, the Difference Scores for the MCI groups were not significantly different than the normals. Further, while patient reported everyday functioning did not differ among the four diagnostic groups, informant reported functional status was significantly different across all diagnostic groups except MCI-nonmemory impaired vs normals. Performance on objective memory testing was associated with informant-rated but not patient-rated functional status. Demographic characteristics of the patients and informants, including ethnicity, had no association with the degree of discrepancy between raters. Conclusions Although there may be some mild functional changes associated particularly with the MCI-memory impaired subtype, individuals with MCI do not appear to under-report their functional status as can often been seen in persons with dementia. Copyright © 2005 John Wiley & Sons, Ltd. [source] Accuracy and Efficiency of Computer-Aided Nursing DiagnosisINTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 3 2008Sachiko Kurashima MSN PURPOSE.,This study aims to determine whether a computer-aided nursing (CAN) diagnosis system improves diagnostic accuracy and efficiency. METHODS.,A randomized crossover trial was performed using two kinds of case studies with 42 nurses as subjects. The subjects were divided into a group using the CAN diagnosis system and a group using a handbook of nursing diagnosis. Degree of accuracy was judged by using Lunney's seven-point interval scale, while efficiency was evaluated by time required for diagnosis. FINDINGS.,There was no significant difference between the two groups in terms of diagnostic accuracy; however, time required for diagnosis was significantly shorter for subjects who used the CAN diagnosis system than for those who did not. Multiple regression analysis showed that the use of the CAN diagnosis system was the only factor associated with the time required for making the nursing diagnosis. CONCLUSIONS.,The use of the CAN diagnosis system improved the efficiency of the diagnostic process without reducing the level of accuracy of nursing diagnoses. PRACTICE IMPLICATIONS.,The use of a computerized system should be a useful tool for implementation of standardized nursing terminologies. [source] Modulation of peritendinous adhesion formation by alginate solution in a rabbit flexor tendon modelJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Jiro Namba Abstract To examine the antiadhesive effect of an alginate solution following tendon surgery, unilateral subtotal laceration of the flexor digitorum communis tendon was created in one hind limb while the other side was left intact in 32 Japanese white rabbits. The lesion was coated with alginate solution in 16 animals and not coated in the other 16. Degree of adhesion formation was assessed histologically and biomechanically by measuring the flexion angle of the first toe when the flexor digitorum tendon was pulled with a specified force at 4 weeks postoperatively. When compared with the control group, the alginate-treated group demonstrated significantly greater toe flexion, with less scar tissue formation at the repair site. Histologically, complete tendon healing with longitudinal remodeling of collagen fibers was observed in the alginate-treated group, while a random pattern of fibers was observed in the control group. Reduction in adhesion formation using alginate solution represents a novel strategy for the management of tendon injury and repair in the clinical setting. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Change of properties during storage of a UDMA/TEGDMA dental resinJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2004Jong Keun Lee Abstract The aim of this study was to evaluate the changes in viscoelastic properties of a UDMA-based dental resin as a function of time after initial light exposure. Specimens of a UDMA/TEGDMA (70:30 wt%) resin were irradiated by a visible-light-curing unit. Immediately after the irradiation, the light-cured specimen was stored in the dark for different times from 1 to 120 h at 37 °C, and characterized by means of DMA, DSC, and FTIR spectroscopy. The irradiated specimen exhibited a bimodal shape in the form of two rapid declines in log E, corresponding to glass transition with a plateau between the two declines. Two distinct peaks were seen in tan , versus temperature. The thermal reaction of the incompletely cured sample with residual groups trapped by the fast reaction during irradiation is responsible for the plateau. After storage, significant changes were observed in dynamic mechanical parameters, DSC exotherm, and degree of conversion. Storage modulus continued to increase during the 4 h of storage and leveled off thereafter. Peak heights of tan , versus temperature were also influenced by storage. Degree of conversion increased from 75 ± 2% immediately after irradiation to 87 ± 3% after 120 h storage. The changes of the properties of this dental resin system when stored at 37 °C after irradiation are clinically important in terms of stability, durability, and performance after initial polymerization. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 68B: 216,221, 2004 [source] Defibrillation Depends on Conductivity Fluctuations and the Degree of Disorganization in Reentry PatternsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2005GERNOT PLANK Ph.D. Introduction: Cardiac fibrillation is the deterioration of the heart's normally well-organized activity into one or more meandering spiral waves, which subsequently break up into many meandering wave fronts. Delivery of an electric shock (defibrillation) is the only effective way of restoring the normal rhythm. This study focuses on examining whether higher degrees of disorganization requires higher shock strengths to defibrillate and whether microscopic conductivity fluctuations favor shock success. Methods and Results: We developed a three-dimensional computer bidomain model of a block of cardiac tissue with straight fibers immersed in a conductive bath. The membrane behavior was described by the Courtemanche human atrial action potential model incorporating electroporation and an acetylcholine- (ACh) dependent potassium current. Intracellular conductivities were varied stochastically around nominal values with variations of up to 50%. A single rotor reentry was initiated and, by adjusting the spatial ACh variation, the level of organization could be controlled. The single rotor could be stabilized or spiral wave breakup could be provoked leading to fibrillatory-like activity. For each level of organization, multiple shock timings and strengths were applied to compute the probability of shock success as a function of shock strength. Conclusions: Our results suggest that the level of the small-scale conductivity fluctuations is a very important factor in defibrillation. A higher variation significantly lowers the required shock strength. Further, we demonstrated that success also heavily depends on the level of organization of the fibrillatory episode. In general, higher levels of disorganization require higher shock strengths to defibrillate. [source] A Two Degree of Freedom Gripper Actuated by SMA with Flexure HingesJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 11 2003A. Manuello Bertetto A gripper prototype was designed and built. It is made by a rigid structure articulated by compliant hinges. Its kinematics consists of both parallel and angular finger motion. The movements were designed to be independent from each other and auto-adaptive as well. The motions were driven by Ni-Ti shape memory alloy (SMA) wires. The recovery position is achieved by the elastic force exerted by the flexure hinges in the case of parallel motion and by an axial spring in the case of angular motion. Both the actuators and the hinges were experimentally characterized by suitable test rigs. The gripper prototype was tested and it showed to be able to reach the design performances. © 2003 Wiley Periodicals, Inc. [source] INFLUENCE OF SUPERCRITICAL CARBON DIOXIDE AND METHANOLIC EXTRACTS OF ROSEMARY ON OXIDATION AND SENSORY PROPERTIES OF WHEAT GERM OILJOURNAL OF FOOD QUALITY, Issue 6 2009OZLEM YESIL-CELIKTAS ABSTRACT Both supercritical CO2 and methanolic extracts from the leaves of rosemary (Rosmarinus officinalis) harvested from three different locations of Turkey at four different times of the year were added at a concentration of 100 mg/kg to wheat germ oil. Wheat germ oil samples were stored in an incubator for 10 days at 50C in order to promote oxidation and for the efficacy of the extracts for stabilization purposes to be examined. Degree of oxidation was determined by peroxide and p -anisidine values, which were performed every 2 days. Extracts from Mersin and Canakkale regions performed better results. Additionally, June and September harvests had lower peroxide values. According to the descriptive sensory analysis, both locations and extraction methods were found to effect flavor. Some flavor attributes, such as wheatlike/starchy, fishy and rubbery/metallic changed during storage regardless of locations and extraction methods. Supercritical CO2 extracts performed better results in terms of both oxidation and sensory properties. PRACTICAL APPLICATIONS From the perspective of the food industry, wheat germ oil stabilized with a natural antioxidant such as rosemary can be marketed as a functional product that can create a niche. Rosemary extracts containing higher amounts of rosmarinic acid and carnosic acid should be preferred in order to provide a better shelf life of an edible oil such as wheat germ oil. [source] Machine Vision Analysis of Antibrowning Potency for Oxalic Acid: A Comparative Investigation on Banana and AppleJOURNAL OF FOOD SCIENCE, Issue 6 2004R. Yoruk ABSTRACT: Relative antibrowning potency of oxalic acid on banana and apple slices was investigated using a machine vision system. Degree of browning on fresh-cut surfaces was evaluated visually and quantitatively by observing changes of CIE L* values and evaluating temporal changes in color spectra based on experimental variables, oxalic acid concentration, and storage time. Browning inhibition was most prominent on banana and apple slices treated with oxalic acid solutions at concentrations of 60 and 5 mM, respectively. Oxalic acid was a more potent antibrowning agent compared with other structurally related acids. Average residual oxalic acid levels in the tissues for an effective antibrowning activity were measured. [source] Method Development for Assessing the Complete Process of Crumbling Cheese Using Hand EvaluationJOURNAL OF FOOD SCIENCE, Issue 4 2004S. Sandra ABSTRACT: Cheese sensory evaluation was conducted by trained panelists (n= 8) on 4 commercial cheese samples (feta, Monterey Jack, 2 brands of Queso Fresco) in duplicate. Fifteen descriptors, capturing the entire process of crumbling cheese, were tested. Degree of crumbliness was defined as the ease by which the sample breaks apart during manipulation by rolling the sample using replicated circular movements, with the thumb, forefinger, and middle finger, 5 times. Using principal component analysis, 4 components were extracted and moistness, crumbliness, color, cohesiveness, irregularity, and oiliness were the main descriptors differentiating the samples. Panelists' performances were not significantly different (P, 0.05), and each subject used the method consistently for crumbliness. [source] Biochemical Properties and Consumer Acceptance of Pacific Whiting Fish SauceJOURNAL OF FOOD SCIENCE, Issue 3 2003S. Tungkawachara ABSTRACT Biochemical characteristics of fish sauce made from Pacific whiting whole fish and a mixture (1:1) of its byproducts were investigated at 0, 1, 3, and 9 mo. As fermentation time extended, the degree of hydrolysis, total nitrogen content, amino nitrogen content, and hypoxanthine content increased, while inosine content, moisture content, and pH decreased. Degree of hydrolysis was significantly different at 9 mo of fermentation. All cathepsin activities were negligible after 3 mo. Consumer tests showed a nonsignificant difference in overall acceptance between our samples and commercial anchovy fish sauce (P > 0.05). This study demonstrated that surimi byproducts can be utilized as raw material for fish sauce. [source] Improved Method for Determining Food Protein Degree of HydrolysisJOURNAL OF FOOD SCIENCE, Issue 5 2001P.M. Nielsen ABSTRACT When producing hydrolyzed proteins, it is important to determine the degree of hydrolysis (DH). The trinitro-benzene-sulfonic acid (TNBS) method is well established with regard to enzymatic hydrolysis. However, this method is laborious, cannot be used to follow a hydrolysis reaction continuously, and includes hazardous and unstable chemicals. This paper describes a method based on the reaction of primary amino groups with o-phthaldialdehyde (OPA). The conclusion is that the OPA method of analyzing the DH of protein hydrolyses is more accurate, is easier and faster to carry out, has a broader application range, and is environmentally safer than the TNBS method. [source] Chemical and Functional Properties of Oxidatively Modified Beef Heart Surimi Stored at 2 °CJOURNAL OF FOOD SCIENCE, Issue 3 2000J.K. Parkington ABSTRACT: Beef heart surimi was prepared using 4 washing conditions: (1) sodium phosphate buffer alone, (2) buffer 1 NaCl, (3) buffer 1 propyl gallate, and (4) buffer 1 sodium tripolyphosphate. Surimi samples were stored at 2 8C and analyzed periodically for protein oxidation, emulsifying properties, and dynamic gelling characteristics. Degree of oxidation differed among washing treatments. Addition of propyl gallate and sodium tripolyphosphate inhibited lipid oxidation but did not prevent protein oxidation. Gel elasticity increased and emulsifying activity decreased for all surimi samples during storage, coinciding with myosin aggregation. Modification of beef heart surimi functionality can be achieved through different washing processes. [source] Prevalence and risk factors of hepatic steatosis and its impact on liver injury in Chinese patients with chronic hepatitis B infectionJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2008Jun-ping Shi Abstract Background and Aims:, The clinical significance of hepatic steatosis in chronic hepatitis B infection (CHB) is unclear. The aims of this study were thus to investigate the prevalence and risk factors for hepatic steatosis in patients with CHB and its relationship with liver injury. Methods:, Consecutive patients with biopsy-proven CHB at Hangzhou Sixth People's Hospital between January 2005 and June 2007 were included. Patients co-infected with other viruses or suffering from liver disease of any other cause were excluded. Liver steatosis, necroinflammation and fibrosis were assessed by both Brunt and Scheuer classifications. Results:, A total of 1915 patients (1497 men) with a mean age of 31 ± 9.5 years were analyzed. Hepatic steatosis was present in 260 (14%) patients. The steatosis involved < 33% of hepatocytes in 90% of cases, and was more frequent among men than women (15% vs 8%, P < 0.001). Two-thirds (178 of 260) of patients with steatosis were hepatitis B e antigen (HBeAg)-positive, but there was no correlation with either serum HBeAg status or hepatitis B virus DNA titer. Degree of inflammation and fibrosis were more mild among those with steatosis than those without. Multivariate analysis showed that steatosis was independently associated with body mass index, serum triglyceride, apolipoprotein B, uric acid, and fasting blood glucose. However, fibrosis was only independently associated with age and inflammatory grade, and the latter associated with viral load and fibrosis stage. Conclusions:, Hepatic steatosis is common in CHB, it is associated with metabolic factors not viral ones, and does not appear to affect the severity of liver disease. [source] Burned by Bullying in the American Workplace: Prevalence, Perception, Degree and Impact*JOURNAL OF MANAGEMENT STUDIES, Issue 6 2007Pamela Lutgen-Sandvik abstract This study assesses the prevalence of workplace bullying in a sample of US workers, using a standardized measure of workplace bullying (Negative Acts Questionnaire, NAQ), and compares the current study's prevalence rates with those from other bullying and aggression studies. The article opens by defining bullying as a persistent, enduring form of abuse at work and contrasting it with other negative workplace actions and interactions. Through a review of the current literature, we propose and test hypotheses regarding bullying prevalence and dynamics relative to a sample of US workers. After discussing research methods, we report on the rates of bullying in a US sample, compare these to similar studies, and analyse the negative acts that might lead to perceptions of being bullied. Based upon past conceptualizations, as well as research that suggests bullying is a phenomenon that occurs in gradations, we introduce and provide statistical evidence for the construct and impact of bullying degree. Finally, the study explores the impact of bullying on persons who witnessed but did not directly experience bullying in their jobs. [source] Characterization of Gonadotrophin-Releasing Hormone Precursor cDNA in the Old World Mole-Rat Cryptomys Hottentotus Pretoriae: High Degree of Identity with the New World Guinea Pig SequenceJOURNAL OF NEUROENDOCRINOLOGY, Issue 5 2005T. Kalamatianos Abstract Regulation of pituitary gonadotrophins by the decapeptide gonadotrophin-releasing hormone 1 (GnRH1) is crucial for the development and maintenance of reproductive functions. A common amino acid sequence for this decapeptide, designated as ,mammalian' GnRH, has been identified in all mammals thus far investigated with the exception of the guinea pig, in which there are two amino acid substitutions. Among hystricognath rodents, the members of the family Bathyergidae regulate reproduction in response to diverse cues. Thus, highveld mole-rats (Cryptomys hottentotus pretoriae) are social bathyergids in which breeding is restricted to a particular season in the dominant female, but continuously suppressed in subordinate colony members. Elucidation of reproductive control in these animals will be facilitated by characterization of their GnRH1 gene. A partial sequence of GnRH1 precursor cDNA was isolated and characterized. Comparative analysis revealed the highest degree of identity (86%) to guinea pig GnRH1 precursor mRNA. Nevertheless, the deduced amino acid sequence of the mole-rat decapeptide is identical to the ,mammalian' sequence rather than that of guinea pigs. Successful detection of GnRH1-synthesizing neurones using either a guinea pig GnRH1 riboprobe or an antibody against the ,mammalian' decapeptide is consistent with the guinea pig-like sequence for the precursor and the classic ,mammalian' form for the decapeptide. The high degree of identity in the GnRH1 precursor sequence between this Old World mole-rat and the New World guinea pig is consistent with the theory that caviomorphs and phiomorphs originated from a common ancestral line in the Palaeocene to mid Eocene, some 63,45 million years ago. [source] Visual Analysis or Semi-Automated Gray-Scale-Based Color Mapping of the Carotid Plaque: Which Method Correlates the Best with the Presence of Cerebrovascular Symptoms and/or Lesions on MRI?JOURNAL OF NEUROIMAGING, Issue 2 2009Isabelle Momjian MD ABSTRACT BACKGROUND AND PURPOSE To determine the correlation between carotid plaque morphology, assessed by two different ultrasonographic methods, and presence of cerebrovascular events and/or lesions on magnetic resonance imaging (MRI). PATIENTS AND METHODS Visual analysis of plaque echogenicity using a five-type classification was performed. Further, a semi-automated gray-scale-based color mapping of the whole plaque and of its surface was achieved. RESULTS There were 31 (35%) symptomatic (23 strokes and 8 transitory ischemic attacks [TIAs]) and 58 (65%) asymptomatic carotid stenoses. MRI lesions related to the carotid stenosis if located in the ipsilateral cortical, subcortical, or watershed area, were present in 27 cases (30%). In a multivariate logistic regression model, degree of stenosis (P= .03) and a predominant red color on the surface (P= .04) were independent factors associated with the presence of cerebrovascular events and/or lesions on MRI. Sensitivity and specificity were, respectively, 80% and 63% by combining degree of stenosis and color mapping of plaque surface. CONCLUSION Degree of stenosis and a predominant red color on plaque surface were independent factors associated with the presence of cerebrovascular events and/or lesions on MRI. No correlation was observed with any particular type of plaque based on visual analysis alone. [source] Ophthalmic Artery Flow Direction on Color Flow Duplex Imaging Is Highly Specific for Severe Carotid StenosisJOURNAL OF NEUROIMAGING, Issue 1 2002Patrick S. Reynolds MD Background/Purpose. Collateral flow patterns are important risk factors for brain ischemia in the presence of internal carotid artery (ICA) stenosis or occlusion. Ophthalmic artery (OA) flow reversal, routinely studied by transcranial Doppler sonography, is an important marker for high-grade ICA stenosis or occlusion. The authors sought to define the value of assessing OA flow direction with color flow duplex ultrasonography (CDUS) in the setting of significant ICA disease. Methods. Of all patients having routine carotid ultrasound in the neurosonology laboratory between July 1995 and November 2000, 152 had both carotid and orbital (OA flow direction by reduced power orbital CDUS) examinations as well as angiographic confirmation of stenosis to which North American Symptomatic Carotid Endarterectomy Trial criteria could be applied. Degree of angiographic stenosis in these 152 patients (304 arteries) was correlated with OA flow direction. Results. Of 304 arteries, 101 had greater than 80% stenosis by angiogram. In 56 of these 101 arteries with high-grade stenosis or occlusion, the ipsilateral OA was reversed; however, OA flow direction was never reversed ipsilateral to arteries with less than 80% stenosis (sensitivity 55%, specificity 100%, negative predictive value 82%, and positive predictive value 100% for OA flow reversal as a marker of high-grade carotid lesions). Discussion/Conclusions. OA flow direction is easily studied with CDUS. Reversed OA flow direction is highly specific (100%) for severe ipsilateral ICA stenosis or occlusion, with excellent positive predictive value, moderate negative predictive value, and limited sensitivity. OA flow reversal is not only quite specific for severe ICA disease, which may be helpful if the carotid CDUS is difficult or inadequate, but may also provide additional hemodynamic insights (ie, the inadequacy of other collateral channels such as the anterior communicating artery). OA evaluation can provide important hemodynamic information and should be included as part of carotid CDUS if there is any evidence of ICA stenosis or occlusion. [source] Degree of conversion and temperature rise during polymerization of composite resin samples with blue diodesJOURNAL OF ORAL REHABILITATION, Issue 6 2001A. Kne To ensure an adequate clinical composite filling light source for photopolymerization is of great importance. In everyday clinical conditions commonly used unit for polymerization of composite material is halogen curing unit. The development of new blue superbright light emitting diodes (LED) of 470 nm wavelengths comes as an alternative to standard halogen curing unit of 450,470 nm wavelengths. The purpose of this study was to compare the degree of conversion (DC) and temperature rise of four hybrid composite materials: Tetric Ceram, Pertac II, Valux Plus and Degufill Mineral during 40 s illulmination with standard halogen curing unit Heliolux GTE of 600 mW cm,2 intensity, Elipar Highlight soft-start curing unit of 100 mW cm,2 (10 s) and 700 mW cm,2 (30 s) intensity and 16 blue superbright LED of minimal intensity of 12 mW cm,2 on the surface and 1 mm depth. The results revealed only a little bit higher DC values in case of polymerization with even 66 times stronger halogen curing units which showed twice higher temperature than blue diodes. Temperature and DC obtained are higher on the surface than on 1 mm depth regardless on the light source used. [source] The rheological properties of modified microcrystalline cellulose containing high levels of model drugsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2009Paul E. Knight Abstract The rheological properties of different types of microcrystalline cellulose (MCC) mixed with model drugs and water have been evaluated to identify the influence of sodium carboxymethylcellulose (SCMC) added to the cellulose during preparation. A ram extruder was used as a capillary rheometer. The mixtures consisted of 20% spheronizing agent (standard grade MCC or modified types with 6% or 8% of low viscosity grade SCMC) and 80% of ascorbic acid, ibuprofen or lactose monohydrate. The introduction of SCMC changed all rheological parameters assessed. It produced more rigid systems, requiring more stress to induce and maintain flow. Degree of non-Newtonian flow, angle of convergence, extensional viscosity, yield and die land shear stress at zero velocity, and static wall friction were increased, but recoverable shear and compliance were decreased. The presence of SCMC did not remove the influence of the type of drug. The mixture of ibuprofen and standard MCC had the lowest values for shear stress as a function of the rate of shear, extensional viscosity, and angle of convergence, but the highest values for recoverable shear and compliance. The findings indicate that the system has insufficient rigidity to form pellets. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2160,2169, 2009 [source] Effect of molecular architecture and size of mesogen on phase behavior and photoactive properties of photoactive liquid crystalline hyperbranched polyester epoxies containing benzylidene moietyJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 2 2008V. Srinivasa Rao Abstract A series of photoactive liquid crystalline linear and hyperbranched polyester epoxies were synthesized by polyaddition of photoactive bis benzylidene alkanone diol monomers and terephthalic acid and trimesic acid respectively with good yield. The effect of molecular architecture (linear and hyperbranched), size of mesogenic unit (cyclic and acyclic units) on the physicochemical, thermal, mesogenic, and photoactive properties of hyperbranched polymers were studied and compared. Degree of branching of hyperbranched polymers was found to be in the range of 0.46,0.49. Monomers containing cyclic moieties only exhibited nematic mesophase, while all polymers exhibited typical nematic mesophase. Intermolecular photo cycloaddition reaction was studied by ultraviolet,visible spectra (UV,vis) and NMR spectroscopy and photo viscosity measurement of UV irradiated polymer solutions. Faster photo induced behavior of hyperbranched polymers containing acyclic alkanone moiety, as compared to polymers containing cycloalkanone moieties, was observed. The change in the refractive index was found to be in the range of 0.02,0.024. Substantial variation of refractive index indicates that this polymer could be used for optical recording. All the polymers were also found to be fluorescent in nature. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 552,563, 2008 [source] Prevalence and Degree of Childhood and Adolescent Overweight in Rural, Urban, and Suburban GeorgiaJOURNAL OF SCHOOL HEALTH, Issue 4 2006Richard D. Lewis The aim of this study was to determine the prevalence of OW and EOW in school-aged youths from 4 regions of Georgia. A 2-stage cluster sampling procedure was performed in 2002, with participation of 4th-, 8th- and 11th-grade students (N = 3114). Measured height and weight were used to determine body mass index (BMI) for age percentiles and data were weighted to estimate population prevalence of OW. A logistic regression model determined predictors of OW. The overall estimate of OW prevalence was 20.2% and highest in males (22.0%), non-Hispanic blacks (21.8%), "other races" (32.4%), and students residing in rural growth (23.7%) and rural decline (23.0%) areas. Overweight prevalence was similar among grades. The overall estimated EOW was 4.3 and highest in males (4.7), other races (5.6), non-Hispanic blacks (5.2), and students from rural growth (5.4) and rural decline (5.0) areas. Sex, race, location, and economic tier were significant predictors (= 0.02) of OW. The prevalence and severity of OW was higher in youths residing in Georgia than nationally. School health professionals, community leaders, and parents should provide support for updated school policies aimed at providing BMI surveillance and a school environment that encourages physical activity and healthy nutrition practices. (J Sch Health. 2006;76(4):126-132) [source] Methylation of Chitosan with Iodomethane: Effect of Reaction Conditions on Chemoselectivity and Degree of SubstitutionMACROMOLECULAR BIOSCIENCE, Issue 10 2003Elisabete Curti Abstract N,N,N -trimethylchitosan (TMC) was prepared by reacting purified chitosan with iodomethane, in the presence of sodium hydroxide, water and sodium iodide, at room temperature. The reaction medium was N -methyl-2-pyrrolidone. Different samples of TMC were obtained by adding to the reaction medium a fixed volume (5.5 mL) of aqueous NaOH solutions at different concentrations (15, 20, 30 and 40 wt.-%) and carrying out the reactions for 9 or 24 h. The features observed in the 1H and 13C NMR spectra of these chitosan derivatives, in respect of the chemical shift, number and relative intensity of the signals, depended strongly on the excess of NaOH and H3CI added to the reaction medium, but when the lowest excess was employed, the characteristics of the derivative were not affected by the reaction time to the same extent. The average degree of quaternization of these N -methylated derivatives of chitosan ranged from 10.5% to 44.8%, according to the reaction conditions. Increasing the excess of NaOH, in reactions carried out for 9 h, resulted in TMC samples with progressively higher content of trimethylated sites however, the reaction yields were correspondingly lower and O -alkylation was favored in these cases. 1H NMR spectrum of sample [AX]24h dissolved in D2O (Cp,=,10 g/L). [source] | |||||||||||||||||||||||||||||||||||||||||||