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Abstract: The effects of disturbance on communities have been a focus of both theoretical and empirical inquiries for many years. Food web stability is hypothesized to be affected by disturbance and the nature of the energy pathways (i.e. allochthonous or autochthonous) of a community. In this study, we investigated whether food webs at paired sites, one in forest and the other in grassland, in ten New Zealand streams along a disturbance gradient differ in their topological structure and robustness. Food web robustness (an indicator of web resistance) assesses the ease with which secondary extinctions permeate the food web following an initial random extinction (disturbance). We found that neither the nature of the energy source nor physical disturbance affected structural metrics or web robustness. As stream systems, particularly in New Zealand, are exposed to regular, unpredictable and dramatic physical disturbance from flooding, it may simply be that the floods result in generalist species dominating and increasing robustness irrespective of the energy source. [ABSTRACT FROM AUTHOR]

Abstract: Evidence based parenting programs have been shown to improve parenting competence and reduce child behavior problems. More rigorous evaluations of such programs are needed in community contexts. This study provides such an evaluation of The Parenting Children Course, a voluntary sector program that is being run both Live and on DVD within a church context. A total of 225 parents participated in the study. Standardized questionnaires were used to measure key parenting variables before and after the course, and at follow‐up 3 months later. Taking the course improved parents’ confidence and reduced parental negativity, but did not improve positive parenting skills. Parents reported that child behavior and family functioning also improved by the end of the course. There were no signs of decay at 3‐month follow‐up. Strengths and limitations of the study, implications for clinical practice and directions for future research, are discussed. [ABSTRACT FROM AUTHOR]

The article discusses a meeting titled "The Health Properties of Cranberry Juice," held at the Royal Society of Medicine in Great Britain on December 3, 2013, to gain views on the health-giving properties of cranberry juice, focusing primarily on urinary tract infections (UTIs). As mentioned, the meeting was chaired by professor Stuart Stanton and topics discussed during the meeting include antibiotic resistance, polyphenol components in cranberries and health benefits of cranberries.

Diabet. Med. 29, 1108-1114 (2012) Abstract Aim To evaluate the extent to which hyperglycaemia was monitored and managed among patients admitted to hospital with acute stroke and transient ischaemic attack. Methods We conducted a retrospective cohort study involving a review of the records of 112 patients consecutively admitted with acute stroke or transient ischaemic attack to all three district general hospitals in one Health and Social Care Trust in Northern Ireland from 1 January to 15 April 2008. Glucose results for each of the first 5 days of hospital admission were ascertained. We compared interventions, clinical outcome and discharge planning between patients who experienced glucose ≥ 7.8 mmol/l in the first 5 days, and patients with lower glucose results. Results The daily prevalence rate of hyperglycaemia > 7.8 mmol/l across the first 5 days ranged from 24 to 34%. A total of 41 (37%) patients experienced hyperglycaemia on at least one occasion during the first 5 days. A history of diabetes mellitus prompted near patient glucose testing, but, among patients without diagnosed diabetes, glycaemia was under-monitored. Hyperglycaemia was a persisting trend, was under-treated and under-reported to general practitioners. Elevated glucose results failed to influence higher rates of fasting plasma glucose tests and BMI assessment. Conclusions There is a need for greater vigilance in the detection of hyperglycaemia and undiagnosed diabetes mellitus among patients admitted to hospital with stroke or transient ischaemic attack. [ABSTRACT FROM AUTHOR]

The article discusses the implementation of consortium guidelines for cytochrome P450-2C19 (CYP2C19) genotype and clopidogrel therapy. It mentions the aim of the guidelines which is to provide information regarding the clinical use of CYP2C19 genotype test results in patients requiring antiplatelet therapy. Moreover, it also provides an overview of the background of CYP2C19 and clopidogrel as well as their genetic test interpretation and suggested clinical actions.

Thiopurine methyltransferase (TPMT) activity exhibits monogenic co-dominant inheritance, with ethnic differences in the frequency of occurrence of variant alleles. With conventional thiopurine doses, homozygous TPMT-deficient patients (~1 in 178 to 1 in 3,736 individuals with two nonfunctional TPMT alleles) experience severe myelosuppression, 30-60% of individuals who are heterozygotes (~3-14% of the population) show moderate toxicity, and homozygous wild-type individuals (~86-97% of the population) show lower active thioguanine nucleolides and less myelosuppression. We provide dosing recommendations (updates at http://www.pharmgkb.org) for azathioprine, mercaptopurine (MP), and thioguanine based on TPMT genotype. [ABSTRACT FROM AUTHOR]

AIM: To update dietetic guidelines summarizing the systematic review evidence on dietary advice to prevent further events in people with existing cardiovascular disease (CVD) (secondary prevention). METHODS: The Cochrane Library, MEDLINE and EMBASE were comprehensively searched to November 2002 for systematic reviews on aspects of diet and heart health. Reviews were included if they searched systematically for randomised controlled trials relating to diet and secondary prevention of CVD. Two members of the UK Heart Health and Thoracic Dietitians Group critically appraised each review. The quality and results of each review were discussed and summarized in a meeting of the whole group. RESULTS: Providing evidence-based dietary information (including increasing omega-3 fat intake) to all people who have had a myocardial infarction will save more lives than concentrating dietary advice on just those in need of weight loss or lipid lowering. The practice of prioritizing dietetic time in secondary prevention to those with raised lipids is out of date since the advent of statin therapy. However, effective dietary advice for those with angina, stroke, peripheral vascular disease or heart failure is less clear. CONCLUSION: There is good systematic review evidence that dietary advice to those with coronary heart disease can reduce mortality and morbidity as well as modify some risk factors. Dietary advice that does this most effectively should be prioritized. [ABSTRACT FROM AUTHOR]

Self-administration of addictive drugs in laboratory animals has been widely used for decades as a tool for studying behavioral, neurobiological, and genetic factors in addiction. From such studies has come an enormous amount of information on brain mechanisms involved in addiction, on vulnerability factors in the addictive process, and on possible pharmacotherapeutic treatments for addiction. Modifications of the laboratory animal self-administration paradigm--including progressive ratio break-point models and the "reinstatement" model of relapse to drug-seeking behavior--are currently increasing our knowledge of incentive motivational factors in addiction and of the mechanisms underlying relapse to drug self-administration behavior. [ABSTRACT FROM AUTHOR]

The article discusses selected scaling techniques. Numerous instruments have been made available to the clinician and guidance counselor to aid him in determining the achievement, aptitudes, attitudes and interests of his clients. Several systems have been based on various growth curves. The most familiar of these units are the isochron scores of Courtis which are defined in terms of the Gompertz curve. However, one of the earliest and certainly the most commonly used attempt to obtain an interval scale was the utilization of the relationship between the shape of the frequency distribution and the units used to obtain it.

The article discusses various psychometric techniques useful in vocational guidance. One of the psychometric techniques is known as pre-test. The pre-test is an instrument, usually paper and pencil, designed to give a rough measure of the subject's mental level in a very short period of time. Another useful psychometric technique identified is the Wechsler-Bellevue Scale. This test gives a measure of verbal and non-verbal intelligence as well as an overall measure and seems to provide satisfactory differentiation at all levels of intelligence.

Precipitin lines were observed in double diffusion tests between mouse gut tissue homogenates and serum from the same animal. Other tissues failed to produce this result. The line-forming components of the tissue are lipoidal while serum reactants are free of lipid. Purified γ-globulin, IgG, does not react with tissue constituents. An IgM component can be identified as one reactant. Lipo- polysaccharides extracted from E. coli 014, Forssman antigen and Kidd-Friede- wald antigen could not be demonstrated as reactants. It appears that certain tissue components which may be lipoproteins, and lipid free serum components, one of which is IgM, react in a way which resembles immunological interactions but which arc believed not to be so. [ABSTRACT FROM AUTHOR]

The Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for Thiopurine Methyltransferase Genotype and Thiopurine Dosing was originally published in March 2011. We reviewed recent literature and concluded that although relevant new evidence has been generated, none of the evidence would change the primary dosing recommendations in the original guideline; therefore, the original publication remains clinically current. Up‐to‐date information on thiopurine methyltransferase (TPMT) gene alleles and nomenclature can be found at PharmGKB (http://www.pharmgkb.org). Clinical Pharmacology & Therapeutics (2013); 93 4, 324–325. doi:10.1038/clpt.2013.4 [ABSTRACT FROM AUTHOR]

Ghrelin is a gastric-derived peptide hormone with demonstrated impact on alcohol intake and craving, but the reverse side of this bidirectional link, that is, the effects of alcohol on the ghrelin system, remains to be fully established. To further characterize this relationship, we examined (1) ghrelin levels via secondary analysis of human laboratory alcohol administration experiments with heavy-drinking participants; (2) expression of ghrelin, ghrelin receptor, and ghrelin-O-acyltransferase (GOAT) genes (GHRL, GHSR, and MBOAT4, respectively) in post-mortem brain tissue from individuals with alcohol use disorder (AUD) versus controls; (3) ghrelin levels in Ghsr knockout and wild-type rats following intraperitoneal (i.p.) alcohol administration; (4) effect of alcohol on ghrelin secretion from gastric mucosa cells ex vivo and GOAT enzymatic activity in vitro; and (5) ghrelin levels in rats following i.p. alcohol administration versus a calorically equivalent non-alcoholic sucrose solution. Acyl- and total-ghrelin levels decreased following acute alcohol administration in humans, but AUD was not associated with changes in central expression of ghrelin system genes in post-mortem tissue. In rats, alcohol decreased acyl-ghrelin, but not des-acyl-ghrelin, in both Ghsr knockout and wild-type rats. No dose-dependent effects of alcohol were observed on acyl-ghrelin secretion from gastric mucosa cells or on GOAT acylation activity. Lastly, alcohol and sucrose produced distinct effects on ghrelin in rats despite equivalent caloric value. Our findings suggest that alcohol acutely decreases peripheral ghrelin concentrations in vivo, but not in proportion to alcohol's caloric value or through direct interaction with ghrelin-secreting gastric mucosal cells, the ghrelin receptor, or the GOAT enzyme., (Published 2021. This article is a U.S. Government work and is in the public domain in the USA.)

In the absence of responding, pigeons were shocked under a variable-time schedule. Responses on either of two keys occasionally produced one minute of shock-free time. That is, pigeons' key pecks were reinforced with shock-free time under concurrent variable-interval schedules. The relative frequency of access to the one-minute shock-free periods was systematically manipulated. Pigeons tended to match both relative response rate and proportion of time spent on each key to the relative frequency of the shock-free periods. A best-fit linear regression equation accounted for over 95% of the variance in both relative response rate and time allocation. The data paralleled closely the results of concurrent schedules of positive reinforcement. These findings are consistent with a description of reinforcement as a transition to a higher-valued situation and suggest that common laws govern choice for both positive and negative reinforcement.

Two avoidance-conditioning experiments in which responding delayed shocks are reported. Rats receiving an average of two shocks per minute (imposed condition) could produce, by pressing a bar, a 3-min alternate condition. Six (Experiment I) or more (Experiment II) shocks occurred in the alternate condition. All shocks in the alternate condition were delayed and delivered at 1-sec intervals. With long delays, all subjects produced the alternate condition and spent a large percentage of each session in the alternate condition. The first experiment demonstrated that the longer the delay from onset of the alternate condition to onset of the shocks, the more session time spent in the alternate condition. The second experiment indicated that despite increased shock frequency, behavior is acquired and maintained when responding leads to sufficient delay. Individual subjects produced the alternate condition by bar pressing in essentially one of two patterns. One pattern, termed postshock, involved bar pressing immediately after shock; the other, termed posttransition, involved responding immediately after the transition from the alternate to the imposed condition. These results indicate that shock-frequency reduction is not necessary for avoidance conditioning; delay to shock onset is sufficient.

Three negative reinforcement experiments employing a key-peck response are described. In Experiment I, pigeons shocked on the average of twice per minute (imposed condition) could produce, by pecking a key, an alternate condition with correlated stimuli. Delayed shocks were added, across sessions, to the alternate condition until pecking stopped. Two of three pigeons continued to peck despite a 100% increase in shock frequency. In Experiment II, pigeons were shocked in the imposed condition four times per minute. The postresponse delay to shock was held constant by delivering, in the alternate condition, the next shock, or the next two, three, or four shocks from the imposed-condition shock schedule. All three subjects continued to peck with no change in delay to the first two postresponse shocks but with a 75% reduction in shock frequency. In Experiment III, a response produced an immediate shock followed by a shock-free period. Three of four subjects continued to respond despite reduced delay to shock. Delay-to-shock or shock-frequency reduction was sufficient to maintain key pecking, but neither was necessary. The conditions that negatively reinforce the pigeon's key peck were similar to conditions that negatively reinforce the rat's bar press.

Rats were shocked at the rate of two per minute until they pressed a lever. In Experiment I, shocks were delivered at variable-time intervals averaging 30 sec; in Experiment II, shocks were delivered at fixed-time intervals of 30 sec. A response produced an alternate condition for a fixed-time period. The shock frequency following a response, calculated over the whole alternate condition, was two per minute. The pattern of shocks in the alternate condition was controlled so that the first shock occurred at the same time as it would have occurred had the response not been emitted; the remaining shocks were delayed until near the end of the alternate condition. Bar pressing was acquired in both experiments. This finding is not explained by two-factor theories of avoidance and is inconsistent with the notion that overall shock-frequency reduction is necessary for negative reinforcement. The data imply that responding is determined by the integrated delays to each shock following a response versus the integrated delays to shock in the absence of a response.