Circularly polarized U-Slot antenna

Circularly polarized single-layer U-slot microstrip patch antenna has been proposed. The suggested asymmetrical U-slot can generate the two orthogonal modes for circular polarization without chamfering any corner of the probe-fed square patch microstrip antenna. A parametric study has been carried out to investigate the effects caused by different arm lengths of the U-slot. The thickness of the foam substrate is about 8.5% of the wavelength at the operating frequency. The 3 dB axial ratio bandwidth of the antenna is 4%. Both experimental and theoretical results of the antenna have been presented and discussed

Lipid transfer proteins do their thing anchored at membrane contact sites… but what is their thing?

Membrane contact sites are structures where two organelles come close together to regulate flow of material and information between them. One type of inter-organelle communication is lipid exchange, which must occur for membrane maintenance and in response to environmental and cellular stimuli. Soluble lipid transfer proteins have been extensively studied, but additional families of transfer proteins have been identified that are anchored into membranes by transmembrane helices so that they cannot diffuse through the cytosol to deliver lipids. If such proteins target membrane contact sites they may be major players in lipid metabolism. The eukaryotic family of so-called Lipid transfer proteins Anchored at Membrane contact sites (LAMs) all contain both a sterol-specific lipid transfer domain in the StARkin superfamily (related to StART/Bet_v1), and one or more transmembrane helices anchoring them in the endoplasmic reticulum (ER), making them interesting subjects for study in relation to sterol metabolism. They target a variety of membrane contact sites, including newly described contacts between organelles that were already known to make contact by other means. Lam1-4p target punctate ER-plasma membrane contacts. Lam5p and Lam6p target multiple contacts including a new category: vacuolar non-NVJ cytoplasmic ER (VancE) contacts. These developments confirm previous observations on tubular lipid-binding proteins (TULIPs) that established the importance of membrane anchored proteins for lipid traffic. However, the question remaining to be solved is the most difficult of all: are LAMs transporters, or alternately are they regulators that affect traffic more indirectly

Trichinella spiralis: specificity of ES antigens from pre-encysted larvae

Excretory/secretory (ES) antigens were obtained by culturing pre-encysted Trichinella spiralis larvae which were recovered from muscles of experimentally infected mice 14-15 days postinfection. Analyses of these antigens (PEL ES) with immunoblotting, SDS-PAGE and Triple Antibody ELISA showed that they yielded a low sensitivity and specificity when tested with antisera against the common nematodes of Chinese pigs. As compared to ES antigens from encysted larvae, PEL ES also contained more low molecular mass proteins.published_or_final_versio

Tubular lipid binding proteins (TULIPs) growing everywhere

Tubular lipid binding proteins (TULIPs) have become a focus of interest in the cell biology of lipid signalling, lipid traffic and membrane contact sites. Each tubular domain has an internal pocket with a hydrophobic lining that can bind a hydrophobic molecule such as a lipid. This allows TULIP proteins to carry lipids through the aqueous phase. TULIP domains were first found in a large family of extracellular proteins related to the bacterial permeability-inducing protein (BPI) and cholesterol ester transfer protein (CETP). Since then, the same fold and lipid transfer capacity have been found in SMP domains (so-called for their occurrence in synaptotagmin, mitochondrial and lipid binding proteins), which localise to intracellular membrane contact sites. Here the methods for identifying known TULIPs are described, and used to find previously unreported TULIPs, one in the silk polymer and another in prokaryotes illustrated by the E. coli protein YceB. The bacterial TULIP alters views on the likely evolution of the domain, suggesting its presence in the last universal common ancestor. The major function of TULIPs is to handle lipids, but we still do not know how they work in detail, or how many more remain to be discovered. This article is part of a Special Issue entitled: Membrane Contact Sites edited by Christian Ungermann and Benoit Kornmann

Advances on the Transfer of Lipids by Lipid Transfer Proteins

Transfer of lipid across the cytoplasm is an essential process for intracellular lipid traffic. Lipid transfer proteins (LTPs) are defined by highly controlled in vitro experiments. The functional relevance of these is supported by evidence for the same reactions inside cells. Major advances in the LTP field have come from structural bioinformatics identifying new LTPs, and from the development of countercurrent models for LTPs. However, the ultimate aim is to unite in vitro and in vivo data, and this is where much progress remains to be made. Even where in vitro and in vivo experiments align, rates of transfer tend not to match. Here we set out some of the advances that might test how LTPs work

A postgraduate diploma course in community geriatrics for primary care doctors: Experience of first three years

This paper describes the setting up of a postgraduate diploma course in Community Geriatrics for primary care physicians and the experience gained in its first three years of running. This study programme was set up in response to the rapidly rising elderly population in Hong Kong and the fact that most of the primary care doctors practising today had an inadequate undergraduate curriculum in the health care issues that are relevant to older people. The objectives of the Course are to improve the knowledge, skills and confidence of primary care physicians in the care of elderly people. It also emphasises the aspects of care that are unique to elderly people. The Course is delivered by different modes of learning: distance learning, face-to-face problem-orientated seminars and small group clinical teaching. Learning centres are established in different regional hospitals in Hong Kong in order to allow small group clinical teaching while, at the same time, reducing travelling time for the students. Information technology is also used to facilitate teaching and learning, as well as to encourage communication among teachers and students. The Course was oversubscribed for all its intakes in the first three years of running. Some graduates have taken on visiting medical officer positions at elderly homes.published_or_final_versio

Amelioration of soils contaminated with radionuclides:Exploiting biodiversity to minimise or maximise soilto plant transfer

Objective: Computed Tomography (CT) is the leading contributor to medical exposure to ionizing radiation. Although the use of CT brain scans for patients with head injuries and convulsions has shown a tremendous growth, it has raised substantial concerns in the general public because of the risk of radiation-induced cataracts: the current available strategies to reduce the radiation dose to the eye lens region are limited. Therefore, the present research project was initiated with the aim of evaluating the potential benefit of the combined use of bolus and a bismuth shield on reducing the radiation dose to the eye lens region during CT brain examination.Materials and methods: We conducted a series of phantom studies to measure the entrance surface dose (ESD) that is delivered to the eye lens region during CT brain examination under the effect of different scanning and shielding setups.Results: Our results indicated, during CT brain examination: (1) a drastic reduction of 92.5% in the ESD to the eye lens region was found when the CT gantry was tilted from 0 degrees (overall ESD = 30.7 mGy) to 30 degrees cranially (overall ESD = 2.4 mGy), and (2) when the CT gantry was positioned at 0 degrees (the common practice in the clinical setting), the setups with the application of a) a bismuth shield, b) a bismuth shield with a face shield (air gap), c) a bismuth shield with bolus, and d) a bismuth shield with bolus and an air gap can result in an acceptable level of image quality with a smaller overall ESD delivered to the eye lens region (overall ESD = 23.2 mGy, 24 mGy, 21 mGy and 19.9 mGy, respectively) than the setup without the bismuth shield applied (overall ESD = 30.7 mGy).Conclusion: When the primary beam scanning through the eye lens region is unavoidable during CT brain examination, the combined use of a bismuth shield with bolus and a face shield is an easy-to-use and inexpensive shielding setup to reduce the radiation dose delivered to the eye lens region while maintaining the correct CT number and a low degree of image noise in the resultant image.Department of Health Technology and Informatic

Ginseng: A panacea linking East Asia and North America?

The Supplement title: The Art and Science of Traditional Medicine Part 3: The Global Impact of Traditional Medicinepostprin

The product of C9orf72, a gene strongly implicated in neurodegeneration, is structurally related to DENN Rab-GEFs

Fronto-temporal dementia (FTD) and amyotrophic lateral sclerosis (ALS, also called motor neuron disease, MND) are severe neurodegenerative diseases that show considerable overlap at the clinical and cellular level. The most common single mutation in families with FTD or ALS has recently been mapped to a non-coding repeat expansion in the uncharacterized gene C9ORF72. Although a plausible mechanism for disease is that aberrant C9ORF72 mRNA poisons splicing, it is important to determine the cellular function of C9ORF72, about which nothing is known

Temperature dependence of current transport in Al/Al 2O 3 nanocomposite thin films

In this work, Al/Al 2O 3 nanocomposite thin film is deposited on Si substrate by radio frequency sputtering to form a metal-insulator-semiconductor structure. It is found that the current conduction at low fields is greatly enhanced with temperature. The current increase can be attributed to the decrease in the tunneling resistance and/or the formation of some tunneling paths due to the release of some measurement-induced charges trapped in the thin film as a result of increase in the temperature. The current conduction evolves with a trend toward a three-dimensional transport as the temperature increases. © 2011 American Institute of Physics.published_or_final_versio