The Influence of Task Characteristics on the Intermanual Asymmetry of Motor Overflow

The two studies reported here were designed to test the proposition that greater motor overflow occurs when movements are performed by the non-dominant hand. Unlike previous studies using normal adults, the task in these studies did not require force production. In the first study, a group of 19 right-handed participants performed unweighted finger lifting. That the frequency of motor overflow occurrence was the same regardless of which hand performed the task, did not support findings from other studies where tasks involving force production resulted in more overflow when performed by the non-dominant hand. To investigate further the influence of task characteristics on motor overflow occurrence, in the second study participants were required to remember and reproduce a prescribed sequence of four finger lifts. Left- and right-handed participants ( N =30) performed both single and sequenced finger lifting. The relative frequency of motor overflow (unintended lifts of fingers of the passive hand) was compared between hand preference groups, active hand and task type (single/sequenced). Contrary to the expectation that motor overflow would be greater for the sequenced finger lifting task, overflow was exhibited with a significantly greater frequency on single finger lifting. This finding indicates that task characteristics influence the pattern of overflow occurrence in normal adults. The task used in this study did not involve force production and did not result in an intermanual asymmetry of motor overflow. This contrasts with findings from other studies requiring adults to exert forces where greater overflow occurred when the non-dominant hand was active. However, this study confirms previous findings which show that left-handers produce greater overflow compared to right-handers regardless of the task being performed and the hand performing the task.

Live high: train low increases muscle buffer capacity and submaximal cycling efficiency

This study investigated whether hypoxic exposure increased muscle buffer capacity (βm) and mechanical efficiency during exercise in male athletes. A control (CON, n=7) and a live high:train low group (LHTL, n=6) trained at near sea level (600 m), with the LHTL group sleeping for 23 nights in simulated moderate altitude (3000 m). Whole body oxygen consumption (V˙O₂) was measured under normoxia before, during and after 23 nights of sleeping in hypoxia, during cycle ergometry comprising 4×4-min submaximal stages, 2-min at 5.6 ± 0.4 W kg^–1, and 2-min 'all-out' to determine total work and V˙O_2peak. A vastus lateralis muscle biopsy was taken at rest and after a standardized 2-min 5.6 ± 0.4 W kg^–1 bout, before and after LHTL, and analysed for βm and metabolites. After LHTL, βm was increased (18%, P < 0.05). Although work was maintained, V˙O_2peak fell after LHTL (7%, P < 0.05). Submaximal V˙O₂ was reduced (4.4%, P < 0.05) and efficiency improved (0.8%, P < 0.05) after LHTL probably because of a shift in fuel utilization. This is the first study to show that hypoxic exposure, per se, increases muscle buffer capacity. Further, reduced V˙O₂ during normoxic exercise after LHTL suggests that improved exercise efficiency is a fundamental adaptation to LHTL.

Regulation of corticotropin-releasing factor concentration and overflow in the rat central nervous system

Examines alterations in corticotropin-releasing factor concentration and nerve release during maturation and aging in the rat brain. Release of neuropeptide Y was also measured. These studies may provide information leading to the effective treatment of age-related disorders.

Factors regulating noradrenaline overflow in the rat brain in vivo and in vitro

High concentrations of the neurotransmitter noradrenaline and the co-transmitter NPY have been reported in discrete regions of the hypothalamus. This study suggests the NPY plays a possible role in the hypothalamus during the pathophysiological condition of ageing possibly through an NPY Y1 receptor. It also provides further evidence for an interaction between NPY and noradrenaline in the central nervous system.

An improved process for the N-demethylation of opiate alkaloids using an iron(II) catalyst in acetate buffer

An improved process to N-demethylate opiate alkaloids utilising a solution of the ferrous porphyrin, tetrasodium 5,10,15,20-tetra(4-sulfophenyl)porphyrinatoiron(II) [=Fe(II)-TPPS (8)], in acetate buffer is described. This method provided the corresponding N-demethylated opiates in good yield with high reproducibility.

Does workplace social capital buffer the effects of job stress? A cross-sectional, multilevel analysis of cigarette smoking among U.S. manufacturing workers

Objective: To investigate whether workplace social capital buffers the association between job stress and smoking status. Methods: As part of the Harvard Cancer Prevention Project's Healthy Directions—Small Business Study, interviewer-administered questionnaires were completed by 1740 workers and 288 managers in 26 manufacturing firms (84% and 85% response). Social capital was assessed by multiple items measured at the individual level among workers and contextual level among managers. Job stress was operationalized by the demand-control model. Multilevel logistic regression was used to estimate associations between job stressors and smoking and test for effect modification by social capital measures. Results: Workplace social capital (both summary measures) buffered associations between high job demands and smoking. One compositional item—worker trust in managers—buffered associations between job strain and smoking. Conclusion: Workplace social capital may modify the effects of psychosocial working conditions on health behaviors.

The association between mindfulness and emotional distress in adults with diabetes: could mindfulness serve as a buffer? Results from Diabetes MILES: the Netherlands

People with diabetes have a higher risk of emotional distress (anxiety, depression) than non-diabetic or healthy controls. Therefore, identification of factors that can decrease emotional distress is relevant. The aim of the present study was to examine (1) the association between facets of mindfulness and emotional distress; and (2) whether mindfulness might moderate the association between potential adverse conditions (stressful life events and comorbidity) and emotional distress. Analyses were conducted using cross-sectional data (Management and Impact for Long-term Empowerment and Success-Netherlands): 666 participants with diabetes (type 1 or type 2) completed measures of mindfulness (Five Facet Mindfulness Questionnaire-Short Form; FFMQ-SF), depressive symptoms (Patient Health Questionnaire; PHQ-9), and anxiety symptoms (General Anxiety Disorder assessment; GAD-7). Hierarchical multiple regression analyses showed significant associations between mindfulness facets (acting with awareness, non-judging, and non-reacting) and symptoms of anxiety and depression (β = -0.20 to -0.33, all p < 0.001). These mindfulness facets appeared to have a moderating effect on the association between stressful life events and depression and anxiety (all p < 0.01). However, the association between co-morbidity and emotional distress was largely not moderated by mindfulness. In conclusion, mindfulness is negatively related to both depression and anxiety symptoms in people with diabetes and shows promise as a potentially protective characteristic against the influence of stressful events on emotional well-being. © 2014 Springer Science+Business Media New York.

Breeding short-tailed shearwaters buffer local environmental variability in south-eastern Australia by foraging in Antarctic waters

BACKGROUND: Establishing patterns of movements of free-ranging animals in marine ecosystems is crucial for a better understanding of their feeding ecology, life history traits and conservation. As central place foragers, the habitat use of nesting seabirds is heavily influenced by the resources available within their foraging range. We tested the prediction that during years with lower resource availability, short-tailed shearwaters (Puffinus tenuirostris) provisioning chicks should increase their foraging effort, by extending their foraging range and/or duration, both when foraging in neritic (short trips) and distant oceanic waters (long trips). Using both GPS and geolocation data-loggers, at-sea movements and habitat use were investigated over three breeding seasons (2012-14) at two colonies in southeastern Australia. RESULTS: Most individuals performed daily short foraging trips over the study period and inter-annual variations observed in foraging parameters where mainly due to few individuals from Griffith Island, performing 2-day trips in 2014. When performing long foraging trips, this study showed that individuals from both colonies exploited similar zones in the Southern Ocean. The results of this study suggest that individuals could increase their foraging range while exploiting distant feeding zones, which could indicate that short-tailed shearwaters forage in Antarctic waters not only to maintain their body condition but may also do so to buffer against local environmental stochasticity. Lower breeding performances were associated with longer foraging trips to distant oceanic waters in 2013 and 2014 indicating they could mediate reductions in food availability around the breeding colonies by extending their foraging range in the Southern Ocean. CONCLUSIONS: This study highlights the importance of foraging flexibility as a fundamental aspect of life history in coastal/pelagic marine central place foragers living in highly variable environments and how these foraging strategies are use to buffer this variability.

Electrogenerated chemiluminescence of tris(2,2' bipyridine)ruthenium(ii) using common biological buffers as co-reactant, pH buffer and supporting electrolyte

A series of aliphatic tertiary amines (HEPES, POPSO, EPPS and BIS-TRIS) commonly used to buffer the pH in biological experiments, were examined as alternative, non-toxic co-reactants for the electrogenerated chemiluminescence (ECL) of tris(2,2'-bipyridine)ruthenium(ii) ([Ru(bpy)3](2+)). These were found to be very attractive as "multi-tasking" reagents, serving not only as co-reactants, but also fulfiling the roles of pH buffer and supporting electrolyte within an aqueous environment; thus significantly simplifying the overall ECL analysis. Sub-nanomolar detection limits were obtained for [Ru(bpy)3](2+) in the presence of BIS-TRIS, making this species an valuable option for co-reactant ECL-based bioanalytical applications.

The adaptable buffer algorithm for high quantile estimation in non-stationary data streams

The need to estimate a particular quantile of a distribution is an important problem which frequently arises in many computer vision and signal processing applications. For example, our work was motivated by the requirements of many semi-automatic surveillance analytics systems which detect abnormalities in close-circuit television (CCTV) footage using statistical models of low-level motion features. In this paper we specifically address the problem of estimating the running quantile of a data stream with non-stationary stochasticity when the memory for storing observations is limited. We make several major contributions: (i) we derive an important theoretical result which shows that the change in the quantile of a stream is constrained regardless of the stochastic properties of data, (ii) we describe a set of high-level design goals for an effective estimation algorithm that emerge as a consequence of our theoretical findings, (iii) we introduce a novel algorithm which implements the aforementioned design goals by retaining a sample of data values in a manner adaptive to changes in the distribution of data and progressively narrowing down its focus in the periods of quasi-stationary stochasticity, and (iv) we present a comprehensive evaluation of the proposed algorithm and compare it with the existing methods in the literature on both synthetic data sets and three large 'real-world' streams acquired in the course of operation of an existing commercial surveillance system. Our findings convincingly demonstrate that the proposed method is highly successful and vastly outperforms the existing alternatives, especially when the target quantile is high valued and the available buffer capacity severely limited.

Who will answer my question on Stack Overflow?

Stack Overflow is a highly successful Community Question Answering (CQA) service for software developers with more than three millions users and more than ten thousand posts per day. The large volume of questions makes it difficult for users to find questions that they are interested in answering. In this paper, we propose a number of approaches to predict who will answer a new question using the characteristics of the question (i.e. Topic) and users (i.e. Reputation), and the social network of Stack Overflow users (i.e. Interested in the same topic). Specifically, our approach aims to identify a group of users (candidates) who have the potential to answer a new question by using feature-based prediction approach and social network based prediction approach. We develop predictive models to predict whether an identified candidate answers a new question. This prediction helps motivate the knowledge exchanging in the community by routing relevant questions to potential answerers. The evaluation results demonstrate the effectiveness of our predictive models, achieving 44% precision, 59% recall, and 49% F-measure (average across all test sets). In addition, our candidate identification techniques can identify the answerers who actually answer questions up to 12.8% (average across all test sets).

Anchoring countercyclical capital buffer in Basel III

This thesis proposes two top-down approch frameworks to assess the Basel III countercyclical capital buffer. The empirical results demonstrate that sovereign sector distance-to-default and market illiquidity are more suitable indicator for guiding the decision of the buffer during both build-up and release phase than the official indicator, credit-to-GDP ratio. The findings in this thesis are important to help safeguard the globe financial system.