Increased hypoxic dose after training at low altitude with 9h per night at 3000m normobaric hypoxia

This study examined effects of low altitude training and a live-high: train-low protocol (combining both natural and simulated modalities) on haemoglobin mass (Hbmass), maximum oxygen consumption (VO2max), time to exhaustion, and submaximal exercise measures. Eighteen elite-level race-walkers were assigned to one of two experimental groups; lowHH (low Hypobaric Hypoxia: continuous exposure to 1380 m for 21 consecutive days; n = 10) or a combined low altitude training and nightly Normobaric Hypoxia (lowHH+NHnight: living and training at 1380 m, plus 9 h.night-1 at a simulated altitude of 3000 m using hypoxic tents; n = 8). A control group (CON; n = 10) lived and trained at 600 m. Measurement of Hbmass, time to exhaustion and VO2max was performed before and after the training intervention. Paired samples t-tests were used to assess absolute and percentage change pre and post-test differences within groups, and differences between groups were assessed using a one-way ANOVA with least significant difference post-hoc testing. Statistical significance was tested at p < 0.05. There was a 3.7% increase in Hbmass in lowHH+NHnight compared with CON (p = 0.02). In comparison to baseline, Hbmass increased by 1.2% (±1.4%) in the lowHH group, 2.6% (±1.8%) in lowHH+NHnight, and there was a decrease of 0.9% (±4.9%) in CON. VO2max increased by ~4% within both experimental conditions but was not significantly greater than the 1% increase in CON. There was a ~9% difference in pre and post-intervention values in time to exhaustion after lowHH+NH-night (p = 0.03) and a ~8% pre to post-intervention difference (p = 0.006) after lowHH only. We recommend low altitude (1380 m) combined with sleeping in altitude tents (3000 m) as one effective alternative to traditional altitude training methods, which can improve Hbmass.

Acute signalling responses to intense endurance training commenced with low or normal muscle glycogen

We have previously demonstrated that well-trained subjects who completed a 3 week training programme in which selected high-intensity interval training (HIT) sessions were commenced with low muscle glycogen content increased the maximal activities of several oxidative enzymes that promote endurance adaptations to a greater extent than subjects who began all training sessions with normal glycogen levels. The aim of the present study was to investigate acute skeletal muscle signalling responses to a single bout of HIT commenced with low or normal muscle glycogen stores in an attempt to elucidate potential mechanism(s) that might underlie our previous observations. Six endurance-trained cyclists/triathletes performed a 100 min ride at ∼70% peak O₂ uptake (AT) on day 1 and HIT (8 × 5 min work bouts at maximal self-selected effort with 1 min rest) 24 h later (HIGH). Another six subjects, matched for fitness and training history, performed AT on day 1 then 1–2 h later, HIT (LOW). Muscle biopsies were taken before and after HIT. Muscle glycogen concentration was higher in HIGH versus LOW before the HIT (390 ± 28 versus 256 ± 67 μmol (g dry wt)⁻¹). After HIT, glycogen levels were reduced in both groups (P < 0.05) but HIGH was elevated compared with LOW (229 ± 29 versus 124 ± 41 μmol (g dry wt)−1; P < 0.05). Phosphorylation of 5'AMP-activated protein kinase (AMPK) increased after HIT, but the magnitude of increase was greater in LOW (P < 0.05). Despite the augmented AMPK response in LOW after HIT, selected downstream AMPK substrates were similar between groups. Phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK) was unchanged for both groups before and after the HIT training sessions. We conclude that despite a greater activation AMPK phosphorylation when HIT was commenced with low compared with normal muscle glycogen availability, the localization and phosphorylation state of selected downstream targets of AMPK were similar in response to the two interventions.

Atmos (piano and guitar)

Atmos (Piano and Guitar) is a short instrumental with piano and guitar.

Managing women with acute physiological deterioration: student midwives performance in a simulated setting

OBJECTIVE: Midwives' ability to manage maternal deterioration and 'failure to rescue' are of concern with questions over knowledge, clinical skills and the implications for maternal morbidity and, mortality rates. In a simulated setting our objective was to assess student midwives' ability to assess, and manage maternal deterioration using measures of knowledge, situation awareness and skill, performance. METHODS: An exploratory quantitative analysis of student performance based upon performance, ratings derived from knowledge tests and observational ratings. During 2010 thirty-five student, midwives attended a simulation laboratory completing a knowledge questionnaire and two video, recorded simulated scenarios. Patient actresses wearing a 'birthing suit' simulated deteriorating, women with post-partum and ante-partum haemorrhage (PPH and APH). Situation awareness was, measured at the end of each scenario. Applicable descriptive and inferential statistical tests were, applied to the data. FINDINGS: The mean total knowledge score was 75% (range 46-91%) with low skill performance, means for both scenarios 54% (range 39-70%). There was no difference in performance between the scenarios, however performance of key observations decreased as the women deteriorated; with significant reductions in key vital signs such as blood pressure and blood loss measurements. Situation, awareness scores were also low (54%) with awareness decreasing significantly (t(32)=2.247, p=0.032), in the second and more difficult APH scenario. CONCLUSION: Whilst knowledge levels were generally good, skills were generally poor and decreased as the women deteriorated. Such failures to apply knowledge in emergency stressful situations may be resolved by repetitive high stakes and high fidelity simulation.

Low impact of chytridiomycosis on frog recruitment enables persistence in refuges despite high adult mortality

The global chytridiomycosis pandemic caused by the pathogen Batrachochytrium dendrobatidis (. Bd) is implicated in the apparent extinction or severe decline of over 200 amphibian species. Many declined species now only persist in isolated remnant populations. In this study we examine how remnant populations coexist with Bd, focusing on disease impact on adult survival and recruitment potential in the chytridiomycosis-threatened frog Litoria verreauxii alpina. Using skeletochronology we found that the adult male population in both 2011 and 2012 was dominated by a two year old age cohort. The lack of recruitment into the three year old cohort in 2012 indicates that annual adult survival is very low. Combined with high Bd prevalence and heavy infection burdens, the pathogen appears to drive almost complete mortality of breeding adults over their first breeding season. However, adults successfully mate prior to large increases in disease prevalence that occurs during the breeding season. Infection prevalence among tadpoles and juveniles is low. Exposure to warm water could provide a mechanism for avoiding or clearing Bd infection. Relatively low Bd prevalence in juveniles prior to dispersal into terrestrial habitat indicates that Bd has minimal impact on early life history stages. As such, recruitment is probably high, allowing populations to persist despite low adult survival. This dependence on reliable annual recruitment may explain why remnant populations persist in permanent ponds rather than ephemeral ponds that were historically occupied. New management strategies that focus on increasing recruitment may provide a way forward for the management of disease-threatened amphibian species.

Influence of fuel-borne oxygen on European stationary cycle: diesel engine performance and emissions with a special emphasis on particulate and NO emissions

Exploration of sustainable fuels and their influence on reductions in diesel emissions are nowadays a challenge for the engine and fuel researchers. This study investigates the role of fuel-borne oxygen on engine performance and exhaust emissions with a special emphasis on diesel particulate and nitric oxide (NO) emissions. A number of oxygenated-blends were prepared with waste cooking biodiesel as a base oxygenated fuel. Triacetin, a derivative from transesterified biodiesel was chosen for its high oxygen content and superior fuel properties. The experimental campaign was conducted with a 6-cylinder, common rail turbocharged diesel engine equipped with highly precise instruments for nano and other size particles and other emissions. All experiments were performed in accordance with European Stationary Cycle (ESC 13-mode). A commercial diesel was chosen as a reference fuel with 0% oxygen and five other oxygenated blends having a range of 6.02–14.2% oxygen were prepared. The experimental results revealed that the oxygenated blends having higher a percentage of fuel-borne oxygen reduced particulate matter (PM), particle number (PN), unburned hydrocarbon (UBHC) and carbon monoxide (CO) emissions to a significantly low level with a slight penalty of NO emissions. The main target of this study was to effectively utilise triacetin as an additive for waste cooking biodiesel and suppress emissions without deteriorating engine performance. The key finding of this investigation is the significant reductions in both particle mass and number emissions simultaneously without worsening engine performance with triacetin-biodiesel blends. Reductions in both particle mass and number emissions with a cost-effective additive would be a new dimension for the fuel and engine researchers to effectively use triacetin as an emission suppressor in the future.

The static and metadynamic recrystallization behaviour of an X60 Nb Microalloyed Steel

A rapid method has been developed to determine recrystallization kinetics of Nb microalloyed steels by interrupted hot torsion test. The softening behaviour was achieved as a function of different processing parameters. The method clearly identified three regions, where the strain dependency of the recrystallization rate varied. Firstly, at large strains the rate of recrystallization was not a function of strain; this is generally ascribed to metadynamic recrystallization. At lower strains the time to 50% recrystallization showed a power low relationship with strain, characteristic of static recrystallization. A further break point exists on the time for 50% softening curve when strain induced precipitation occurs in the material. The onset of strain induced precipitation was at strains below the strain to the peak stress at temperatures below 900°C. The experimental results were used to estimate the time for 50% softening and to anticipate the onset of the strain induced precipitation for the alloy of this study. Grain refinement of the recrystallized austenite continued to strains significantly beyond the peak stress and beyond the static to metadynamic recrystallization rate transition.

Globalisation and manufacturing strategy in the TCF industry

Purpose – The textiles, clothing, and footwear (TCF) industry has struggled in Australia since the government commenced dismantling tariffs. By sourcing from Asia, middlemen undercut established suppliers, and retail chains set benchmark low prices with their imported “house” labels. The policy-makers predicted that local producers would become more efficient, and export to make up for lost sales, but the media paints a picture of rising imports, retrenchments, and factory closures. The research objective was to discover what strategies the survivors (actually) employ in adapting to the pressures of globalisation.

Design/methodology/approach – More than 30 companies were involved in the study, ranging from small family businesses to subsidiaries of big multinationals. Each case study was based on an interview with a senior executive, normally followed by a plant tour. This methodology suits a fresh topic, as it avoids preconceptions and imposes no bounds.

Findings – Results show that the policy change was based on “pie in the sky” forecasts. Increasingly, TCF production is transferred to cheap offshore locations, generally via subcontracting plus the “badging” of foreign designs. To survive, local factories should focus on quality and customer service, preferably in niche markets (like uniforms), or for specific customer groups, and develop technologically advanced products. A move down the supply chain into retailing can also assist. Large multinational corporations that engage in foreign direct investment dominate the management literature.

Originality/value – This paper presents a different perspective, neglected in international operations management, whereby domestically oriented businesses attempt to defend themselves against the adverse consequences of globalisation.

Medical image classification using an efficient data mining technique

Data mining refers to extracting or "mining" knowledge from large amounts of data. It is an increasingly popular field that uses statistical, visualization, machine learning, and other data manipulation and knowledge extraction techniques aimed at gaining an insight into the relationships and patterns hidden in the data. Availability of digital data within picture archiving and communication systems raises a possibility of health care and research enhancement associated with manipulation, processing and handling of data by computers.That is the basis for computer-assisted radiology development. Further development of computer-assisted radiology is associated with the use of new intelligent capabilities such as multimedia support and data mining in order to discover the relevant knowledge for diagnosis. It is very useful if results of data mining can be communicated to humans in an understandable way. In this paper, we present our work on data mining in medical image archiving systems. We investigate the use of a very efficient data mining technique, a decision tree, in order to learn the knowledge for computer-assisted image analysis. We apply our method to the classification of x-ray images for lung cancer diagnosis. The proposed technique is based on an inductive decision tree learning algorithm that has low complexity with high transparency and accuracy. The results show that the proposed algorithm is robust, accurate, fast, and it produces a comprehensible structure, summarizing the knowledge it induces.

The quality of the LMX relationship, the currency of exchange, and emotions at work

Leader-member exchange (LMX) is a theory of leadership that specifically focuses on the quality of the relationship between a manager and his/her subordinates. Previous research has shown the link between LMX quality and employee attitudes and behaviours at work. However, to the authors' knowledge, research is yet to specifically investigate the link between LMX quality and employee emotions. Also little understood are the social exchanges that lead to and maintain LMX quality ("currencies of exchange" in LMX theory). We introduce the notion of currency of exchange quality - whether the currency is present to a good enough extent or not (either in absence or excess) - and theoretically link this to employee emotions.
A field study was designed and conducted to investigate the links. The study supported the propositions that high LMX relationships with good enough currency quality resulted in more positive employee emotions; low LMX with an absence of currency quality resulted in more negative emotions; and low LMX with an excess of currency quality resulted in mixed emotions. An unexpected finding was that high LMX was also associated with excess currency quality and mixed emotions. The affective evaluations and discrete emotions experienced varied according to the currency and its quality.

Sex-role traits and the comorbidity of symptoms of disordered eating and problem drinking

The symptoms of problem drinking and disordered eating were studied independently in relation to sex-role traits and also for evidence of comorbidity in a student sample of 217 women. The participants completed surveys that assessed positive and negative sex-role traits, reported drinking levels, alcohol dependence, problem drinking, bulimic symptoms, dietary restraint, and drive for thinness. Eating symptoms were related to both the negative and positive traits of Femininity, but self-descriptions involving negative traits (passivity, dependence, unassertiveness, etc.) showed the strongest relationship. High scores on identification with the traits typically labelled as Masculinity were related to drinking but there was an important difference between drinking per se (which was related to Positive Masculinity) and drinking found to be associated with drinking problems, which was related to Negative Masculinity (aggression, showing-off, rudeness, etc.). Feminine traits were also related to drinking. Low identification with the traits of Negative Femininity was associated with non-problem drinking, whereas low identification with the traits of Positive Femininity were associated with problem-related drinking. Young women who displayed comorbid symptoms described themselves by a high identification with the traits of both Negative Masculinity and Negative Femininity. It was argued that comorbidity reveals a more extreme form of the sex-role conflict previously described in relation to disordered control over both eating and drinking when considered independently.

Older persons' perception of risk of falling : implications for fall-prevention campaigns

Objectives. We examined older people's attitudes about falls and implications for the design of fall-prevention awareness campaigns.

Methods. We assessed data from (1) computer-assisted telephone surveys conducted in 2002 with Australians 60 years and older in Northern Rivers, New South Wales (site of a previous fall-prevention program; n=1601), and Wide Bay, Queensland (comparison community; n=1601), and (2) 8 focus groups (n=73).

Results. Participants from the previous intervention site were less likely than were comparison participants to agree that falls are not preventable (odds ratio [OR]=0.76; 95% confidence interval [Cl]=0.65, 0.90) and more likely to rate the prevention of falls a high priority (OR=1.31; 95% CI=1.09, 1.57). There was no difference between the groups for self-perceived risk of falls; more than 60% rated their risk as low. Those with a low perceived risk were more likely to be men, younger, partnered, and privately insured, and to report better health and no history of falls. Focus group data indicated that older people preferred messages that emphasized health and independence rather than falls.

Conclusions. Although older people accepted traditional fall-prevention messages, most viewed them as not personally relevant. Messages that promote health and independence may be more effective.

Mismatch between perceived and objective measures of physical activity environments

Objectives : This study investigated the correspondence between measures of physical activity facilities obtained through self-report and objective audits; and identified the socio-demographic, cognitive and behavioral characteristics of those who perceive their physical activity environment to be less supportive than objective measures indicate.
Methods : Self-report surveys were completed by 1540 women recruited from 45 neighborhoods in Melbourne, Australia. Women reported perceived access to physical activity facilities within 2 km from home, and also socio-demographic, cognitive and behavioral factors. Objective data on physical activity facilities within a 2 km pedestrian catchment area around women's homes were sourced.
Results : There was relatively poor agreement between measures of access to physical activity facilities obtained via self-report and objective assessment. Mismatch between perceived and objectively-assessed environments was more common amongst younger and older women, and women of low income, with low self-efficacy for physical activity, who were less active, who reported using fewer facilities and who had lived in the neighborhood for less than 2 years.
Conclusions : Future studies of environmental determinants of physical activity should consider incorporating objective indices of access to facilities, or accounting for the systematic bias that may result from relying on self-report perceptions as an indicator of the actual physical activity environment.

Are shocks to energy consumption permanent or temporary? evidence from 182 countries

This article applies univariate and panel data unit root tests to annual panel data for 182 countries over the period 1979–2000 to examine the stationarity properties of per capita energy consumption. The univariate unit root test can only reject the unit root null for 56 countries or 31% of the sample at the 10% level or better. However, univariate unit root tests have low power with short spans of data and therefore failure to reject the unit root null should be treated with caution. When we apply the panel data unit root test we find overwhelming evidence that energy consumption is stationary. We discuss the policy implications of these findings and offer suggestions for future research.

Steroidogenesis in cultured mammalian glial cells

A protocol for culturing mammalian type 1 astrocytic cells, using female post-natal rat cerebral cortical tissue, was established and refined for use in steroidogenic metabolic studies incorporating progestin radioisotopes. Cultures were characterised for homogeneity using standard morphological and immunostaining techniques. Qualitative and quantitative studies were conducted to characterise the progesterone (P) metabolic pathways present in astrocytes in vitro. Of particular interest was the formation of the P metabolite, 5á-pregnan-3á-ol-20-one (THP). THP is a GABA(A) receptor agonist, believed to play a vital role in neural functioning and CNS homeostasis. One aim of this study was to observe any modulatory effects selected neuroactive ligands have on the conversion of P into THP, in an attempt to link astrocytic steroidogenesis with neuronal control. In qualitative studies, chromatographic procedures were used to establish the progestin profile of cerebral cortical astrocytes. Tritiated P, DHP (5á-pregnan-3,20-dione) and THP incurbates were preliminary fractionated by either normal phase (NP) or reverse phase (RP) high performance liquid chromatography (HPLC). The radiometabolites associated with each fraction were further chromatographed, before and/or after chemical derivatistation, by the aforemention HPLC procedures and thin layer chromatography (TLC). Steroid radiometabolites were tentatively identified by comparing their chromatographic mobility with authentic steroids. The identity of the main putative 5á-reduced P metabolities, DHP, THP and 5á-pregnan-3á,20á-diol (20áOH-THP) were further confirmed by isotopic dilution analysis. Their conclusive identification, along with the tentative identification of 20á-hydroxypreg-4-en-3-one (20áOH-P) and 20á-hydroxy-5á-pregnan-3-one (20áOH-DHP), verify the localisation of 5á-reductase, 3á-hydroxy steroif oxidoreductase (HSOR), and 20á-HSOR activity in the cultured astrocytes utilised in this study programme. Other minor metabolites detected were tentatively identified, including 5á-pregnan-3á,21-diol-20-one (THDoc), indicating the presence of 21-hydroxylase enzymatic activity. THDoc, like THP, is a GABA(A) receptor agonist. The chemical and physical characterisation of several yet unidentified progestin metabolites, associated with a highly polar RP HPLC fraction (designated RP peak 1*), indicate the presence of one or more extra hydroxylase enzymes. Quantitative analysis included a preliminary study. In this study, the percentage yields of radiometabolites formed in cultures incubated with increasing substrate concentrations of (3)H-P for 24 hours were determined. At the lower concentrations examined (ie 0.5 to 50nM), the metabolites associated with the polar RP HPLC fraction (RP peak 1*) collectively have the highest percentage yield. They are subsequently considered metabolic end products of degradative catabolic P pathways. The percentage yield of THP peaks in the medium concentration ranges (ie 5 to 500nM), whereas DHP remains fairly static at a low level with increasing concentration. Both DHP and THP are considered metabolic pathway intermediates. The percentage yield of 20áOH-THP continues to increase with increasing concentration over 5nM, superseding THP approaching the highest concentration examined (5000nM). This indicated the formation of 20áOH-THP does not occur entirely via THP. 20áOH-THP also possibly serves as the direct intermediate in the formation of the main radiometabolites associated with RP peak 1*. A time/yield study incorporating incubation times from one to 24 hours was also conducted. The full array of radiometabolites (individually or in groups) formed in astrocyte cultures incubated with 50nM tritiated P, DHP of THP, were assayed. Cultures were observed to rapidly convert any DHP into THP, showing astrocytic 3á-HSOR activity is very high. The study also showed 5á-reduction (ie the conversation of P into DHP) is the rate limiting reaction in the two step conversion of P into THP. 5á-Reduction also appears to be a rate limiting step in the formation of 20á-hydroxylated metabolites in astrocytes. Cultures incubated with the tritiated 5á-reduced pregnanes from one to four hours form greater quantities to 20á-hydroxylated radiometabolites compared to cultures incubated with (3)H-P. The time yield/studies also provided further evidence the unidentified polar radiometabolites associated with RP peak 1* are metabolic end products. For the P and DHP incubates, the collective formation of the aforementioned polar radiometabolites initially lags behind the formation of THP. As the formation of the latter begins to plateau with increasing time between four to 24 hours, the net yield of radiometabolites associated with RP peak 1* continues to rise. The time/yield studies also indicate 5á-reduction and perhaps 3á-hydroxylation are pre-requisite steps in the formation of the polar metabolites. Cultures incubated with the 5á-reduced progestins from one to four hours form higher yields of the radiometabolites associated with RP peak 1* compared to cultures incubated with P as substrate. The net yields of the radiometabolites associated with RP peak 1* for cultures incubated with THP were substantially higher compared to cultures incubated with DHP after equivalent times. The effect selected neuroligands have on the yield of radiometabolites formed by cultured astrocytes incubated with 50nM (3)H-P was also examined. Dibutyryl cyclic adenosine monophosphate (DBcAMP), not actually a neuroligand per se, but an analog of the intracellular secondary messenger cAMP, was also utilised in these studies. The inhibitory neurotransmitter ă-amino-nbutyric acid (GABA), DBcAMP and isoproterenol (a â-adrenergic receptor agonist) all quickly induce a transient but substantial increase in 20á-HSOR activity in cultured astrocytes. Cultures pretreated with these three compounds (10, 20 and 1µM respectively) form substantially higher yields of 20á-hydroxylated metabolites, including 20áOH-THP (between 200 to 580% greater), when incubated with 50nM (3)H-P for one to four hours. These increases also coincide with increases in the net yield of metabolites formed (by 16 to 48%). The same pre-treated cultures form significantly lower yields of THP, by 25 to 41%, after one hour. This is most likely due to the increased metabolism of any formed THP into 20áOH-THP. Octopamine (an á-adrenergic agonist) only induces a slight increase in 20á-HSOR activity, having relatively little effect on the yield of 20áOH-THP formed. Pretreatment with octopamine induces a significant increase in the yield of THP for cultures incubated with (3)H-P for four hours (by 24%). The increase in THP formation appears to be due to an increase in 3á-HSOR activity, as judged by the concomitant drop in the yield of the 5á-reduced, 3-keto substrates. An increase in 5á-reductase activity cannot be excluded however. Isoproterenol appears to induce an increase in 5á-reductase activity as isoproterenol appears to induce an increase in 5á-reductase activity as isoproterenol one and four hour incubates have higher yields of DHP. This is in contrast to the other three incubates. After 12 hours, all incubates have higher yields of THP (15-30%).