A flow-through hydrothermal cell for in situ neutron diffraction studies of phase transformations

A flow-through hydrothermal cell for the in situ neutron diffraction study of crystallisation and phase transitions has been developed. It can be used for kinetic studies on materials that exhibit structural transformations under hydrothermal conditions. It is specifically designed for use on the medium-resolution powder diffractometer (MRPD) at ANSTO, Lucas Heights, Sydney. But it is planned to adapt the design for the Polaris beamline at ISIS and the new high-intensity powder diffractometer (Wombat) at the new Australian reactor Opal. The cell will operate in a flow-through mode over the temperature range from 25–300 1C and up to pressures of 100 bar. The first results of a successful transformation of pentlandite (Fe,Ni)9S8 to violarite (Fe,Ni)3S4 under mild conditions (pH4) at 120 1C and 3 bar using in situ neutron diffraction measurements are presented

A simplified design method for estimating the fire performance of structural timber floors

The widespread use of structural timber in tall buildings is often inhibited because timber is a combustible material and is commonly perceived to behave poorly in fires. This research develops a simplified design approach for the fire performance of different types of prefabricated timber floors used in multi-storey buildings. The floor types under investigation include several different geometries of box-shaped and T-shaped timber floors made from Laminated Veneer Lumber (LVL). The investigations were carried out with numerical simulations and four experimental fire tests. A simplified design method to estimate the fire resistance of unprotected timber floor assemblies is proposed and calibrated against the numerical and experimental work. The method uses a bi-linear charring rate and the assumption of a zero strength layer in the timber. The method is compared to the experimental data from this research and others around the world, as well as charring rate methodologies from around the world

Successful Downstaging of High Rectal and Recto-Sigmoid Cancer by Neo-Adjuvant Chemo-Radiotherapy

© 2008 Libertas Academica Ltd. All rights reserved.Purpose: The benefit of neoadjuvant therapy for tumours above the peritoneal reflection is not clear. The purpose of this study is to demonstrate the feasibility and downstaging of treating locally advanced tumours from high rectum to distal sigmoid with preoperative chemoradiotherapy (CRT).Methods and Materials: Seventeen patients with high rectal, rectosigmoid or distal sigmoid tumours above the peritoneal reflection received neoadjuvant CRT, selected on MRI findings indicating T4 disease or threatened circumferential resection margin. All patients were administered neoadjuvant chemotherapy, with Oxaliplatin or Mitomycin C and a Fluoropyrimidine. The pelvis received long-course CT-planned conformal RT, 45 Gy in 25 fractions, with a boost of 5.4–9 Gy in 3–5 fractions. Thirteen patients were treated with concomitant oral or intravenous Fluoropyrimidine chemotherapy.Results: Median follow-up was 37 months. Overall survival was 82.35% (95% Confidence Interval (CI) 54.7–93.9) and disease free survival 81.25% (95% CI 52.5–93.5). Only 1 patient suffered loco-regional relapse. Chemotherapy regimens were well tolerated, though some patients required dose reductions. Nine patients (52.9%) lowered pathologic disease AJCC stage, i.e. ‘downstaged’. Six patients (35.3%) achieved complete pathological response. Clear margins were attained in all but 1 patient. Three patients were converted from cT4 to ypT3. No patient required a gap during CRT. One patient suffered a grade III acute toxicity, but no grade IV (RTOG). There were 3 grade III and 3 grade IV late toxicities (LENT-SOMA).Conclusions: Locally advanced high rectal and recto-sigmoid tumours may be treated with pre-operative CRT with acceptable toxicity, impressive down-staging, and clear surgical margins

Enhancing genome assemblies by integrating non-sequence based data

INTRODUCTION Many genome projects were underway before the advent of high-throughput sequencing and have thus been supported by a wealth of genome information from other technologies. Such information frequently takes the form of linkage and physical maps, both of which can provide a substantial amount of data useful in de novo sequencing projects. Furthermore, the recent abundance of genome resources enables the use of conserved synteny maps identified in related species to further enhance genome assemblies. METHODS The tammar wallaby (Macropus eugenii) is a model marsupial mammal with a low coverage genome. However, we have access to extensive comparative maps containing over 14,000 markers constructed through the physical mapping of conserved loci, chromosome painting and comprehensive linkage maps. Using a custom Bioperl pipeline, information from the maps was aligned to assembled tammar wallaby contigs using BLAT. This data was used to construct pseudo paired-end libraries with intervals ranging from 5-10 MB. We then used Bambus (a program designed to scaffold eukaryotic genomes by ordering and orienting contigs through the use of paired-end data) to scaffold our libraries. To determine how map data compares to sequence based approaches to enhance assemblies, we repeated the experiment using a 0.5× coverage of unique reads from 4 KB and 8 KB Illumina paired-end libraries. Finally, we combined both the sequence and non-sequence-based data to determine how a combined approach could further enhance the quality of the low coverage de novo reconstruction of the tammar wallaby genome. RESULTS Using the map data alone, we were able order 2.2% of the initial contigs into scaffolds, and increase the N50 scaffold size to 39 KB (36 KB in the original assembly). Using only the 0.5× paired-end sequence based data, 53% of the initial contigs were assigned to scaffolds. Combining both data sets resulted in a further 2% increase in the number of initial contigs integrated into a scaffold (55% total) but a 35% increase in N50 scaffold size over the use of sequence-based data alone. CONCLUSIONS We provide a relatively simple pipeline utilizing existing bioinformatics tools to integrate map data into a genome assembly which is available at http://www.mcb.uconn.edu/fac.php?name=paska. While the map data only contributed minimally to assigning the initial contigs to scaffolds in the new assembly, it greatly increased the N50 size. This process added structure to our low coverage assembly, greatly increasing its utility in further analyses

Chestnut-crowned babbler calls are composed of meaningless shared building blocks

A core component of human language is its combinatorial sound system: meaningful signals are built from different combinations of meaningless sounds. Investigating whether non-human communication systems are also combinatorial is hampered by difficulties in identifying the extent to which vocalizations are constructed from shared, meaningless building blocks. Here we present a novel approach to circumvent this difficulty and show that a pair of functionally distinct chestnut-crowned babbler (Pomatostomus ruficeps) vocalizations can be decomposed into perceptibly distinct, meaningless entities that are shared across the two calls. Specifically, by focusing on the acoustic distinctiveness of sound elements using a habituation-discrimination paradigm on wild-caught babblers under standardized aviary conditions, we show that two multi-element calls are composed of perceptibly distinct sounds that are reused in different arrangements across the two calls. Furthermore, and critically, we show that none of the five constituent elements elicits functionally relevant responses in receivers, indicating that the constituent sounds do not carry the meaning of the call; so are contextually meaningless. Our work, which allows combinatorial systems in animals to be more easily identified, suggests that animals can produce functionally distinct calls that are built in a way superficially reminiscent of the way that humans produce morphemes and words. The results reported lend credence to the recent idea that language’s combinatorial system may have been preceded by a superficial stage where signalers neither needed to be cognitively aware of the combinatorial strategy in place, nor of its building blocks

White-matter abnormalities in brain during early abstinence from methamphetamine abuse

Previous studies revealed microstructural abnormalities in prefrontal white matter and corpus callosum of long-term abstinent chronic methamphetamine abusers. In view of the importance of the early abstinence period in treatment retention, we compared 23 methamphetamine-dependent subjects abstinent from methamphetamine for 7–13 days with 18 healthy comparison subjects. As certain metabolic changes in the brain first manifest after early abstinence from methamphetamine, it is also possible that microstructural white-matter abnormalities are not yet present during early abstinence. Using diffusion tensor imaging at 1.5 T, fractional anisotropy (FA) was measured in prefrontal white matter at four inferior–superior levels parallel to the anterior commissure–posterior commissure (AC–PC) plane. We also sampled FA in the corpus callosum at the midline and at eight bilateral, fiber-tract sites in other regions implicated in effects of methamphetamine. The methamphetamine group exhibited lower FA in right prefrontal white matter above the AC–PC plane (11.9% lower; p = 0.007), in midline genu corpus callosum (3.9%; p = 0.019), in left and right midcaudal superior corona radiata (11.0% in both hemispheres, p’s = 0.020 and 0.016, respectively), and in right perforant fibers (7.3%; p = 0.025). FA in left midcaudal superior corona radiata was correlated with depressive and generalized psychiatric symptoms within the methamphetamine group. The findings support the idea that methamphetamine abuse produces microstructural abnormalities in white matter underlying and interconnecting prefrontal cortices and hippocampal formation. These effects are already present during the first weeks of abstinence from methamphetamine and are linked to psychiatric symptoms assessed during this period

The Dilemma of Using Sward Height as a Management Tool for Intensively Grazed Sheep Pasture in Spring

Sward height is often used as a tool for both animal and pasture management, especially when continuously grazing pasture. For example, sward height has been used to define the conditions for optimal feed intake of multiple-bearing ewes, both before and after lambing (Everett-Hincks et al.2005; Morris and Kenyon 2004). Sward height is easily applied by the grazier and so becomes an effective tool. However, changes in the leaf distribution and relative species makeup of the sward both seasonally (Thomson et al. 2001) and in response to grazing management (Webby and Pengelly 1986) mean that the amount of pasture per unit height will change. When these changes occur a dilemma is presented to the grazier. How do they manage the trade-off between a simple indicator for management decisions and the lost opportunity of harvesting pasture mass that may be accumulating below the assigned sward height? This paper presents data from an experiment that investigated the impacts of defoliation strategies on sward of differing starting masses, with defoliation management based on height rather than mass. The paper quantifies the accumulation of herbage below defoliation height and highlights the dilemma of using sward height as a management tool when aiming to maximise the utilisation of our pasture resource

Specialist palliative care nursing and the philosophy of palliative care: a critical discussion

Nursing is the largest regulated health professional workforce providing palliative care across a range of clinical settings. Historically, palliative care nursing has been informed by a strong philosophy of care which is soundly articulated in palliative care policy, research and practice. Indeed, palliative care is now considered to be an integral component of nursing practice regardless of the specialty or clinical setting. However, there has been a change in the way palliative care is provided. Upstreaming and mainstreaming of palliative care and the dominance of a biomedical model with increasing medicalisation and specialisation are key factors in the evolution of contemporary palliative care and are likely to impact on nursing practice. Using a critical reflection of the authors own experiences and supported by literature and theory from seminal texts and contemporary academic, policy and clinical literature, this discussion paper will explore the influence of philosophy on nursing knowledge and theory in the context of an evolving model of palliative care

Older Worker-Orientated Human Resource Practices, Wellbeing and Leave Intentions: A Conservation of Resources Approach for Ageing Workforces

At a time where there are ageing populations, global shortages of skilled labour, and migration pathways impacted by the COVID-19 pandemic, retaining older workers presents as a vital strategic initiative for organizations globally. This study examines the role of Human Resource Practices (HRPs), which are oriented towards accommodating the needs of an ageing workforce in mitigating psychological distress and turnover intentions. The study collected self-reported survey data from 300 Australian employees over the age of 45, over two time points. Using structural equation modelling, the study analyzed the extent to which Older Worker-oriented Human Resources Practices (OW-HRPs) translate into employee psychological health and retention within organizations, through the mediation of ageism and work–life conflict. The results support our hypothesis that OW-HRPs are associated with lower ageism, better work–life balance; and in combination these reduce psychological distress and help retain older workers in the workforce. We conclude that OW-HRPs can foster work environments conducive to older worker wellbeing, supporting the retention of talent and maintaining effectiveness, in the face of substantial labour supply challenges brought on by the COVID-19 pandemic and an ageing population

Computational Design of Novel Insulin Degrading Enzyme Inhibitors

Human insulin degrading enzyme (IDE) plays a role in the proteolytic cleavage of insulin, glucagon, and other short, hydrophobic peptides with roles in glucose and cellular metabolism. Because of IDE’s role in insulin clearance, IDE inhibitors may hold promise as therapies for potentiating insulin signaling in patients suffering from type 2 diabetes mellitus. IDE is a large (~100 kDa) chambered protease of the conserved M16A subfamily of zinc metalloproteases. The enzyme adopts a structure that is analogous to a clamshell formed by the joining of the N terminal and C terminal domains. The characteristic zinc binding and catalytic motif (HXXEH) is positioned within the enzyme’s N terminus, while C terminal residues also play important roles in substrate binding and catalysis. Here, we describe the use of a computational work-flow for identifying novel IDE inhibitors. The work flow integrates mutation-based active site structural analysis, virtual screening, docking and fragment-based design. Initial computational results appear promising and should lead to assay testing in the near future