Differential temporal expression of milk miRNA during the lactation cycle of the marsupial tammar wallaby (Macropus eugenii)

Lactation is a key aspect of mammalian evolution for adaptation of various reproductive strategies along different mammalian lineages. Marsupials, such as tammar wallaby, adopted a short gestation and a relatively long lactation cycle, the newborn is immature at birth and significant development occurs postnatally during lactation. Continuous changes of tammar milk composition may contribute to development and immune protection of pouch young. Here, in order to address the putative contribution of newly identified secretory milk miRNA in these processes, high throughput sequencing of miRNAs collected from tammar milk at different time points of lactation was conducted. A comparative analysis was performed to find distribution of miRNA in milk and blood serum of lactating wallaby.

FracSym: automated symbolic computation of Lie symmetries of fractional differential equations

In this paper, we present an algorithm for the systematic calculation of Lie point symmetries for fractional order differential equations (FDEs) using the method as described by Buckwar & Luchko (1998) and Gazizov, Kasatkin & Lukashchuk (2007, 2009, 2011). The method has been generalised here to allow for the determination of symmetries for FDEs with n independent variables and for systems of partial FDEs. The algorithm has been implemented in the new MAPLE package FracSym (Jefferson and Carminati 2013) which uses routines from the MAPLE symmetry packages DESOLVII (Vu, Jefferson and Carminati, 2012) and ASP (Jefferson and Carminati, 2013). We introduce FracSym by investigating the symmetries of a number of FDEs; specific forms of any arbitrary functions, which may extend the symmetry algebras, are also determined. For each of the FDEs discussed, selected invariant solutions are then presented. © 2013 Elsevier B.V. All rights reserved.

Evolution of the electrochemical capacitance of transition metal oxynitrides with time: the effect of ageing and passivation

A number of transition metal nitrides and oxynitrides, which are actively investigated today as electrode materials in a wide range of energy conversion and storage devices, possess an oxide layer on the surface. Upon exposure to ambient air, properties of this layer progressively change in the process known as "ageing". Since a number of electrochemical processes involve the surface or sub-surface layers of the active electrode compounds only, ageing could have a significant effect on the overall performance of energy conversion and storage devices. In this work, the influence of the ageing of tungsten and molybdenum oxynitrides on their electrochemical properties in supercapacitors is explored for the first time. Samples are synthesised by the temperature-programmed reduction in NH3 and are treated with different gases prior to exposure to air in order to evaluate the role of passivation in the ageing process. After the synthesis, products are subjected to controlled ageing and are characterised by low temperature nitrogen adsorption, X-ray photoelectron spectroscopy and transmission electron microscopy. Capacitive properties of the compounds are evaluated by performing cyclic voltammetry and galvanostatic charge and discharge measurements in the 1 M H2SO4 electrolyte. © 2014 the Partner Organisations.

Privacy preserving in location data release: A differential privacy approach

Communication devices with GPS chips allow people to generate large volumes of location data. However, location datasets have been confronted with serious privacy concerns. Recently, several privacy techniques have been proposed but most of them lack a strict privacy notion, and can hardly resist the number of possible attacks. This paper proposes a private release algorithm to randomize location datasets in a strict privacy notion, differential privacy. This algorithm includes three privacy-preserving operations: Private Location Clustering shrinks the randomized domain and Cluster Weight Perturbation hides the weights of locations, while Private Location Selection hides the exact locations of a user. Theoretical analysis on utility confirms an improved trade-off between the privacy and utility of released location data. The experimental results further suggest this private release algorithm can successfully retain the utility of the datasets while preserving users’ privacy.

A survey on differential privacy and applications

Privacy preserving in data release and mining is a hot topic in the information security field currently. As a new privacy notion, differential privacy (DP) has grown in popularity recently due to its rigid and provable privacy guarantee. After analyzing the advantage of differential privacy model relative to the traditional ones, this paper surveys the theory of differential privacy and its application on two aspects, privacy preserving data release (PPDR) and privacy preserving data mining (PPDM). In PPDR, we introduce the DP-based data release methodologies in interactive/non-interactive settings and compare them in terms of accuracy and sample complexity. In PPDM, we mainly summarize the implementation of DP in various data mining algorithms with interface-based/fully access-based modes as well as evaluating the performance of the algorithms. We finally review other applications of DP in various fields and discuss the future research directions.

Glucose administration and cognitive function: differential effects of age and effort during a dual task paradigm in younger and older adults

RATIONALE: Current research suggests that glucose facilitates performance on cognitive tasks which possess an episodic memory component and a relatively high level of cognitive demand. However, the extent to which this glucose facilitation effect is uniform across the lifespan is uncertain. METHODS: This study was a repeated measures, randomised, placebo-controlled, cross-over trial designed to assess the cognitive effects of glucose in younger and older adults under single and dual task conditions. Participants were 24 healthy younger (average age 20.6 years) and 24 healthy older adults (average age 72.5 years). They completed a recognition memory task after consuming drinks containing 25 g glucose and a placebo drink, both in the presence and absence of a secondary tracking task. RESULTS AND CONCLUSIONS: Glucose enhanced recognition memory response time and tracking precision during the secondary task, in older adults only. These findings do not support preferential targeting of hippocampal function by glucose, rather they suggest that glucose administration differentially increases the availability of attentional resources in older individuals.

Glucose enhancement of recognition memory: differential effects on effortful processing but not aspects of 'remember-know' responses

The administration of a glucose drink has been shown to enhance cognitive performance with effect sizes comparable with those from pharmaceutical interventions in human trials. In the memory domain, it is currently debated whether glucose facilitation of performance is due to differential targeting of hippocampal memory or whether task effort is a more important determinant. Using a placebo-controlled, double-blind, crossover 2(Drink: glucose/placebo) × 2(Effort: ± secondary task) design, 20 healthy young adults' recognition memory performance was measured using the 'remember-know' procedure. Two high effort conditions (one for each drink) included secondary hand movements during word presentation. A 25 g glucose or 30 mg saccharine (placebo) drink was consumed 10 min prior to the task. The presence of a secondary task resulted in a global impairment of memory function. There were significant Drink × Effort interactions for overall memory accuracy but no differential effects for 'remember' or 'know' responses. These data suggest that, in some circumstances, task effort may be a more important determinant of the glucose facilitation of memory effect than hippocampal mediation. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

Skipping swans: fuelling rates and wind conditions determine differential use of migratory stopover sites of Bewick's Swans Cygnus bewickii

Some migratory birds refuel at stopover sites that they by-pass on the return trip. In theory, this skipping behaviour is only expected in time-selected migrants when the overflown site is of a lower quality than the departure site. We provide empirical evidence that quality differences in stopover sites are the cause for skipping in Bewick's Swans Cygnus bewickii tracked by satellite telemetry. Two and five complete tracks were recorded in spring and autunm, respectively, showing that the White Sea was visited for c. 2 weeks in spring, but by-passed (or visited for a few days at the most) in autumn. Skipping of the White Sea in autumn was predicted by a dynamic programming model which was based on calculated gain rates during stopover in the Pechora Delta and the White Sea. This prediction was not sensitive to plausible variations in gain rates. Relative to the Pechora Delta the White Sea is a poor site because a large tidal amplitude precludes foraging on the beds of the submerged macrophyte Fennel Pondweed Potamogeton pectinatus during high tide. The dynamic programming model predicted a fast autunm migration. However, the phenology of autunm arrival dates of Bewick's Swans on the wintering grounds revealed that only in three out of ten years a significant number of birds was able to reach the wintering grounds without refuelling. In the other years, unfavourable wind conditions along the Russian/Baltic part of the route prevented such non-stop migration.

A self-supported, flexible, binder-free pseudo-supercapacitor electrode material with high capacitance and cycling stability from hollow, capsular polypyrrole fibers

Flexible energy devices with high performance and long-term stability are highly promising for applications in portable electronics, but remain challenging to develop. As an electrode material for pseudo-supercapacitors, conducting polymers typically show higher energy storage ability over carbon materials and larger conductivity than transition-metal oxides. However, conducting polymer-based supercapacitors often have poor cycling stability, attributable to the structural rupture caused by the large volume contrast between doping and de-doping states, which has been the main obstacle to their practical applications. Herein, we report a simple method to prepare a flexible, binder-free, self-supported polypyrrole (PPy) supercapacitor electrode with high cycling stability through using novel, hollow PPy nanofibers with porous capsular walls as a film-forming material. The unique fiber structure and capsular walls provide the PPy film with enough free-space to adapt to volume variation during doping/de-doping, leading to super-high cycling stability (capacitance retention > 90% after 11000 charge-discharge cycles at a high current density of 10 A g^-1) and high rate capability (capacitance retention ∼ 82.1% at a current density in the range of 0.25-10 A g^-1).

Gender differences in adolescent depression: Differential female susceptibility to stressors affecting family functioning

Objective: The aim of this study was to examine associations between family-based stressors and depressive symptoms in adolescents.

Method: Participants were 10-14 year olds who participated in a large Australian population study (n=6,552). Depressive symptoms and pubertal development were assessed using the self-report Short Mood and Feelings Questionnaire and the Pubertal Development Scale. Three indicators of stress exposure were examined-low emotional closeness to parents, residential and school transitions, and family conflict. The effect of gender, stress exposure and the interaction of gender and stress exposure on depressive symptoms was tested using multivariate logistic regression.

Results: High family conflict, residential instability and low emotional closeness with parents were independently associated with adolescent depressive symptoms. There was a significant gender by emotional closeness interaction; females reporting low emotional closeness to their parents were 2.3 times more likely to report high depressive symptoms than females reporting high emotional connections with parents.

Conclusions: Female adolescents may be more susceptible to particular types of stresses and particularly the quality of the parent-child relationship.

Differential labour market impacts from disability onset

We estimate the causal labour market impacts of disability onset by gender, age and education levels up to 4 years after onset using longitudinal data from the Household Income and Labour Dynamics Australia survey and difference-in-difference propensity score matching techniques. We find lasting negative impacts on employment, especially full-time employment, which is due more to reduced movement into full-time employment than downshifting from full-time to part-time work following onset. Those without post-school education qualifications are particularly vulnerable to the impacts of onset and are more likely to be out of work and on income support than those with qualifications up to 4 years after onset, due in part because they have greater difficulty adjusting.

Differential atrophy of the lower-limb musculature during prolonged bed-rest

Patients with medical, orthopaedic and surgical conditions are often assigned to bed-rest and/or immobilised in orthopaedic devices. Although such conditions lead to muscle atrophy, no studies have yet considered differential atrophy of the lower-limb musculature during inactivity to enable the development of rehabilitative exercise programmes. Bed-rest is a model used to simulate the effects of spaceflight and physical inactivity. Ten male subjects underwent 56-days of bed-rest. Magnetic resonance imaging of the lower-limbs was performed at 2-weekly intervals during bed-rest. Volume of individual muscles of the lower-limb and subsequently, rates of atrophy were calculated. Rates of atrophy differed (F = 7.4, p < 0.0001) between the muscles with the greatest rates of atrophy seen in the medial gastrocnemius, soleus and vastii (p < 0.00000002). The hamstring muscles were also affected (p < 0.00015). Atrophy was less in the ankle dorsiflexors and anteromedial hip muscles (p > 0.081). Differential rates of atrophy were seen in synergistic muscles (e.g. adductor magnus > adductor longus, p = 0.009; medial gastrocnemius > lateral gastrocnemius, p = 0.002; vastii > rectus femoris, p = 0.0002). These results demonstrate that muscle imbalances can occur after extended periods of reduced postural muscle activity, potentially hampering recovery on return to full upright body position. Such deconditioned patients should be prescribed "closed-chain" simulated resistance exercises, which target the lower-limb antigravity extensor muscles which were most affected in bed-rest.

Differential atrophy of the postero-lateral hip musculature during prolonged bedrest and the influence of exercise countermeasures

As part of the 2nd Berlin BedRest Study (BBR2-2), we investigated the pattern of muscle atrophy of the postero-lateral hip and hamstring musculature during prolonged inactivity and the effectiveness of two exercise countermeasures. Twenty-four male subjects underwent 60 days of head-down tilt bedrest and were assigned to an inactive control (CTR), resistive vibration exercise (RVE), or resistive exercise alone (RE) group. Magnetic resonance imaging (MRI) of the hip and thigh was taken before, during, and at end of bedrest. Volume of posterolateral hip and hamstring musculature was calculated, and the rate of muscle atrophy and the effect of countermeasure exercises were examined. After 60 days of bedrest, the CTR group showed differential rates of muscle volume loss (F = 21.44; P ≤ 0.0001) with fastest losses seen in the semi-membranosus, quadratus femoris and biceps femoris long head followed by the gluteal and remaining hamstring musculature. Whole body vibration did not appear to have an additional effect above resistive exercise in preserving muscle volume. RE and RVE prevented and/or reduced muscle atrophy of the gluteal, semi-membranosus, and biceps femoris long head muscles. Some muscle volumes in the countermeasure groups displayed faster recovery times than the CTR group. Differential atrophy occurred in the postero-lateral hip musculature following a prolonged period of unloading. Short-duration high-load resistive exercise during bedrest reduced muscle atrophy in the mono-articular hip extensors and selected hamstring muscles. Future countermeasure design should consider including isolated resistive hamstring curls to target this muscle group and reduce the potential for development of muscle imbalances.

Interns are from Venus, consultants are from Mars: differential perception among clinicians

OBJECTIVE: To test for the presence of sex-based differences in perception (the notion that men and women "think" differently, and that differences in perception are biologically based) among healthcare professionals. DESIGN: Prospective survey. SETTING AND PARTICIPANTS: 90 medical personnel at a tertiary care hospital in Newcastle, NSW. INTERVENTION: Healthcare professionals were shown two pictures that could be interpreted as depicting either a young or an old person, and a word that could be seen as geometric shapes. MAIN OUTCOME MEASURES: The effects of sex, age, seniority, and specialisation in relation to the first impression of the image, the ability to change one's perception, and the speed of perception. RESULTS: Contrary to popular opinion, male physicians were more likely to perceive the older figures, and just as likely as women to be able to change their perception. Surgeons and junior staff were more likely to see, as well as being faster to form, an impression requiring abstract thought, and were more able to change their perceptions. CONCLUSIONS: Traditional sex stereotypes do not apply to medical personnel, but other age-based stereotypes, and professional rivalries (medical versus surgical) may have some empiric basis.