Mechanisms of optical angular momentum transfer to nematic liquid crystalline droplets

A detailed study is presented that evaluates the relative importance of wave plate behavior, scattering processes and absorption phenomena in transferring optical torque from circularly polarized light to optically trapped nematic droplets. A wide range of parameters is considered: droplet diameters between 1 and 15 µm, birefringence values from 0.15 to 0.26 and trapping beam powers from 50 mW to 400 mW. Wave plate behavior is verified through the dependence of torque on droplet diameter and material birefringence. The dependence of the magnitude of the torque on material birefringence confirms the additional importance of the scattering mechanism. Absorption processes are found to be negligible

Instructional Methods that Foster the Reading Development of Students with Significant Intellectual Disabilities

Educational legislation has made reading a priority for students with significant intellectual disabilities (ID) and associated speech, language, sensory, or physical impairments. Historically, reading instruction for students with significant ID has focused on sight word instruction, with limited exposure to other essential reading skills. This article focuses on the evidence-based instructional methods that effectively and efficiently foster the reading development of students with significant ID. The authors reviewed the literature from the past 20 years on reading interventions for students with significant ID. In spite of access and opportunity barriers that have inhibited the reading development of students with significant ID, a synthesis of the empirical research on reading instruction suggests that students with significant ID and associated disabilities can learn phonemic awareness, phonics, vocabulary, fluency, and comprehension skills with direct instruction. Implications for providing reading instruction that effectively promotes reading development are discussed and areas for future research are identified

Up and down the number line: modelling collaboration in contrasting school and home environments

This paper is concerned with user modelling issues such as adaptive educational environments, adaptive information retrieval, and support for collaboration. The HomeWork project is examining the use of learner modelling strategies within both school and home environments for young children aged 5 – 7 years. The learning experience within the home context can vary considerably from school especially for very young learners, and this project focuses on the use of modelling which can take into account the informality and potentially contrasting learning styles experienced within the home and school

ACCERT: Auckland's cancer cachexia evaluating resistance training study

Background: Cancer Cachexia (CC) is a common problem seen in many advanced malignancies including Non- Small-Cell Lung Cancer (NSCLC). In CC there is a significant loss of adipose tissue and skeletal muscle mass. Muscle wasting is the main cause of impaired function, leading to respiratory complications and fatigue. The optimal treatment for CC is the complete removal of the tumour; unfortunately with advanced NSCLC this is unachievable. The next best options are to increase nutritional intake to counteract weight loss, address the anorexia, inflammation, and metabolic alterations i.e. loss of body fat and the skeletal muscle wasting. This requires the need to utilise a multi-targeted approach to decrease the inflammation and to stimulate the skeletal anabolic pathways with the use of progressive resistance training (PRT). PRT has shown acceptability and benefits in other cancer populations. This study aims to identify a novel multi-targeted treatment regimen that will alleviate and/or stabilise CC weight loss. Methods: This is a randomised, open-label study to investigate whether 2 sessions each week of PRT followed by essential amino acids (EAA's) high in leucine, when administered in addition to Eicosapentaenoic Acid (EPA) and a Cox-2 inhibitor is acceptable to NSCLC cachectic patients for a period of 20 weeks (primary endpoint). Secondary endpoints include Lean Body Mass, MRI thigh skeletal muscle values, QoL and Fatigue questionnaires, serum pro-inflammatory cytokine profiles, and hand and leg strength. Safety data will also be collected. Outcome measures to power a future study will be determined from the trend in difference between the two groups. 21 patients are planned to be randomised in a 1:2 ratio Arm A EPA and Cox-2 inhibitor vs. Arm B EPA, Cox-2 inhibitor, PRT followed by EAA's. All patients are offered to continue with the study medications and/or PRT sessions on compassionate use. Main inclusion criteria include: histological proven NSCLC patients who have at least 5% weight loss and fulfil the following cachectic definition (Evans Clin Nut 2008 27). A guest patient was enrolled in May 2012, followed by study participants in June 201

A self-consistent model of Galactic stellar and dust infrared emission and the abundance of polycyclic aromatic hydrocarbons

We present a self-consistent three-dimensional Monte-Carlo radiative transfer model of the stellar and dust emission in the Milky-Way, and have computed synthetic observations of the 3.6 to 100 microns emission in the Galactic mid-plane. In order to compare the model to observations, we use the GLIMPSE, MIPSGAL, and IRAS surveys to construct total emission spectra, as well as longitude and latitude profiles for the emission. The distribution of stars and dust is taken from the SKY model, and the dust emissivities includes an approximation of the emission from polycyclic aromatic hydrocarbons in addition to thermal emission. The model emission is in broad agreement with the observations, but a few modifications are needed to obtain a good fit. Firstly, by adjusting the model to include two major and two minor spiral arms rather than four equal spiral arms, the fit to the longitude profiles for |l|>30 degrees can be improved. Secondly, introducing a deficit in the dust distribution in the inner Galaxy results in a better fit to the shape of the IRAS longitude profiles at 60 and 100 microns. With these modifications, the model fits the observed profiles well, although it systematically under-estimates the 5.8 and 8.0 microns fluxes. One way to resolve this discrepancy is to increase the abundance of PAH molecules by 50% compared to the original model, although we note that changes to the dust distribution or radiation field may provide alternative solutions. Finally, we use the model to quantify which stellar populations contribute the most to the heating of different dust types, and which stellar populations and dust types contribute the most to the emission at different wavelengths.Comment: Published in A&A. This version has been revised (compared to the published version) to include additional references to previous work. Scripts to reproduce the results in this paper can be found as supplementary material on the A&A site, or at https://github.com/hyperion-rt/paper-galaxy-rt-mode

Mechanistic insights into the C₅₅-P targeting lipopeptide antibiotics revealed by structure-activity studies and high-resolution crystal structures

AbstractThe continued rise of antibiotic resistance is a global concern that threatens to undermine many aspects of modern medical practice. Key to addressing this threat is the discovery and development of new antibiotics that operate by unexploited modes of action. The so-called calcium-dependent lipopeptide antibiotics (CDAs) are an important emerging class of natural products that provides a source of new antibiotic agents rich in structural and mechanistic diversity. Notable in this regard is the subset of CDAs comprising the laspartomycins and amphomycins/friulimicins that specifically target the bacterial cell wall precursor undecaprenyl phosphate (C55-P). In this study we describe the design and synthesis of new C55-P-targeting CDAs with structural features drawn from both the laspartomycin and amphomycin/friulimicin classes. Assessment of these lipopeptides revealed previously unknown and surprisingly subtle structural features that are required for antibacterial activity. High-resolution crystal structures further indicate that the amphomycin/friulimicin-like lipopeptides adopt a unique crystal packing that governs their interaction with C55-P and provides an explanation for their antibacterial effect. In addition, live-cell microscopy studies provide further insights into the biological activity of the C55-P targeting CDAs highlighting their unique mechanism of action relative to the clinically used CDA daptomycin.Microbial Biotechnolog

'What is this corpus about?': Using topic modelling to explore a specialised corpus

This paper introduces topic modelling, a machine learning technique that automatically identifies 'topics' in a given corpus. The paper illustrates its use in the exploration of a corpus of academic English. It first offers the intuitive explanation of the underlying mechanism of topic modelling and describes the procedure for building a model, including the decisions involved in the model-building process. The paper then explores the model. A topic in topic models is characterised by a set of co-occurring words, and we will demonstrate that such topics bring us rich insights into the nature of a corpus. As exemplary tasks, this paper identifies the prominent topics in different parts of papers, investigates the chronological change of a journal, and reveals different types of papers in the journal. The paper further compares topic modelling to two more traditional techniques in corpus linguistics, semantic annotation and keywords analysis, and highlights the strengths of topic modelling.We believe that topic modelling is particularly useful in the initial exploration of a corpus

Phase fluctuations, dissipation and superfluid stiffness in d-wave superconductors

We study the effect of dissipation on quantum phase fluctuations in d-wave superconductors. Dissipation, arising from a nonzero low frequency optical conductivity which has been measured in experiments below $T_c$, has two effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction of the temperature at which one crosses over to classical thermal fluctuations. For parameter values relevant to the cuprates, we show that the crossover temperature is still too large for classical phase fluctuations to play a significant role at low temperature. Quasiparticles are thus crucial in determining the linear temperature dependence of the in-plane superfluid stiffness. Thermal phase fluctuations become important at higher temperatures and play a role near $T_c$.Comment: Presentation improved, new references added (10 latex pages, 3 eps figures). submitted to PR