Plasma electrons above Saturn's main rings: CAPS observations

We present observations of thermal ( similar to 0.6 - 100eV) electrons observed near Saturn's main rings during Cassini's Saturn Orbit Insertion (SOI) on 1 July 2004. We find that the intensity of electrons is broadly anticorrelated with the ring optical depth at the magnetic footprint of the field line joining the spacecraft to the rings. We see enhancements corresponding to the Cassini division and Encke gap. We suggest that some of the electrons are generated by photoemission from ring particle surfaces on the illuminated side of the rings, the far side from the spacecraft. Structure in the energy spectrum over the Cassini division and A-ring may be related to photoelectron emission followed by acceleration, or, more likely, due to photoelectron production in the ring atmosphere or ionosphere

The impacts of habitat disturbance on adult and larval dragonflies (Odonata) in rainforest streams in Sabah, Malaysian Borneo

$\textbf{1.}$ Dragonfly assemblages (Odonata: comprising damselflies, Zygoptera; and dragonflies, Anisoptera) in Southeast Asian rainforests are extremely diverse but increasingly threatened by habitat disturbance, including logging and conversion of forest to oil palm plantations. $\textbf{2.}$ Land-use change can affect dragonfly larval stages by altering within-stream environmental conditions, and adults by loss of perches, shade and hunting habitat. However, the extent to which dragonflies are affected by land-use change is not well known, and strategies for conservation are poorly developed. $\textbf{3.}$ We surveyed dragonfly adults and larvae, forest quality and stream environmental conditions across 16 streams in Sabah, Malaysia. Habitat surrounding the streams included pristine forest, selectively logged forest, oil palm with forested riparian buffer strips and oil palm without buffers. $\textbf{4.}$ Overall abundance and species richness of adult dragonflies stayed constant with habitat disturbance, but larval abundance and richness decreased with higher habitat disturbance, and larvae were largely absent from oil palm streams. There was also a clear shift in community composition of both adult and larval dragonflies. Anisoptera adults were more species rich and abundant, but Zygoptera adults were less species rich in more disturbed sites. $\textbf{5.}$ The presence of riparian buffers in oil palm plantations offered some protection for forest-associated dragonfly species, and streams with wider riparian buffers supported adult assemblages more similar to those found in logged forest. However, oil palm streams with riparian buffers still contained a depauperate larval assemblage compared to logged forest areas, and dragonfly assemblages in narrow riparian buffer streams were similar to those found in streams surrounded by continuous oil palm. $\textbf{6.}$ Our results provide clear evidence of the effect of land-use change on dragonflies. Conservation efforts to conserve forest communities should target the preservation of existing forest areas, but management within oil palm plantation landscapes to preserve riparian buffers can still have a marked beneficial effect on dragonfly communities.SHL was funded by a Natural Environment Research Council (NERC) studentship (1122589), Proforest, the Varley Gradwell Travelling Fellowship, Tim Whitmore Fund, Panton Trust and the Cambridge University Commonwealth Fund during this work. We have no conflicts of interest to declare

Effect of Sida corymbosa leaf extract on serum uric acid, urea and creatinine levels of alloxan-induced diabetic albino wistar rats

This study was designed to investigate the effect of Sida corymbosa (SC) leaf extract on serum uric acid, urea and creatinine levels in alloxan induced diabetic albino wistar rats. A total of 30 albino wistar rats each weighing 100g were assembled and divided into three groups (A-C) consisting of 10 rats in each group. Group A received SC treatment, B did not receive SC treatment, while group C served as the control group. 400mg/kg of aqueous extract of SC leaf was administered orally to the rats in group A but not in group B, while group C received only water for 7 days. Blood samples were collected into plain containers for estimation of serum uric acid, urea and creatinine. Serum uric acid, urea and creatinine were analyzed using Uricase, Urease-Berthlot and Jaffe Slot Alkaline picrate methods respectively. Results showed a significant increase in the mean serum levels of uric acid, urea and creatinine after SC treatment, when compared to the pre- treatment status. Similarly, there was a significant decrease in the mean weight of the rats after SC administration. Therefore, SC may have potential harmful effect on the kidney.Keywords: Sida corymbosa, Kidney, Urea, Uric Acid, Creatinine

Characterising hyperinsulinaemia induced insulin resistance in human skeletal muscle cells

Hyperinsulinaemia potentially contributes to insulin resistance in metabolic tissues, such as skeletal muscle. The purpose of these experiments was to characterise glucose uptake, insulin signalling and relevant gene expression in primary human skeletal muscle-derived cells (HMDCs), in response to prolonged insulin exposure (PIE) as a model of hyperinsulinaemia-induced insulin resistance. Differentiated HMDCs from healthy human donors were cultured with or without insulin (100 nM) for 3 days followed by an acute insulin stimulation. HMDCs exposed to PIE were characterised by impaired insulin-stimulated glucose uptake, blunted IRS-1 phosphorylation (Tyr612) and Akt (Ser473) phosphorylation in response to an acute insulin stimulation. Glucose transporter 1 (GLUT1), but not GLUT4, mRNA and protein increased following PIE. The mRNA expression of metabolic (PDK4) and inflammatory markers (TNF-α) was reduced by PIE but did not change lipid (SREBP1 and CD36) or mitochondrial (UCP3) markers. These experiments provide further characterisation of the effects of PIE as a model of hyperinsulinaemia-induced insulin resistance in HMDCs

Elastic properties of graphyne-based nanotubes

Graphyne nanotubes (GNTs) are nanostructures obtained from rolled up graphyne sheets, in the same way carbon nanotubes (CNTs) are obtained from graphene ones. Graphynes are 2D carbon-allotropes composed of atoms in sp and sp2 hybridized states. Similarly to conventional CNTs, GNTs can present different chiralities and electronic properties. Because of the acetylenic groups (triple bonds), GNTs exhibit large sidewall pores that influence their mechanical properties. In this work, we studied the mechanical response of GNTs under tensile stress using fully atomistic molecular dynamics simulations and density functional theory (DFT) calculations. Our results show that GNTs mechanical failure (fracture) occurs at larger strain values in comparison to corresponding CNTs, but paradoxically with smaller ultimate strength and Young's modulus values. This is a consequence of the combined effects of the existence of triple bonds and increased porosity/flexibility due to the presence of acetylenic groups

Sign-reversal of the in-plane resistivity anisotropy in hole-doped iron pnictides

The in-plane anisotropy of the electrical resistivity across the coupled orthorhombic and magnetic transitions of the iron pnictides has been extensively studied in the parent and electron-doped compounds. All these studies universally show that the resistivity $\rho_{a}$ across the long orthorhombic axis $a_{O}$ - along which the spins couple antiferromagnetically below the magnetic transition temperature - is smaller than the resistivity $\rho_{b}$ of the short orthorhombic axis $b_{O}$, i. e. $\rho_{a}<\rho_{b}$. Here we report that in the hole-doped compounds Ba$_{1-x}$K$_{x}$Fe$_{2}$As$_{2}$, as the doping level increases, the resistivity anisotropy initially becomes vanishingly small, and eventually changes sign for sufficiently large doping, i. e. $\rho_{b}<\rho_{a}$. This observation is in agreement with a recent theoretical prediction that considers the anisotropic scattering of electrons by spin-fluctuations in the orthorhombic/nematic state.Comment: This paper has been replaced by the new version offering new explanation of the experimental results first reported her

Food fortification and biofortification as potential strategies for prevention of vitamin D deficiency

Hypovitaminosis D (vitamin D deficiency) is widespread throughout the world. The cutaneous production of vitamin D through sunlight can be limited by several factors (e.g. skin pigmentation, sunscreen usage and, increasingly, indoor lifestyle). Thus, diet has become an important strategy to increase vitamin D intake and status {blood 25-hydroxyvitamin D [25(OH)D]}. However, there are a limited number of foods that naturally contain vitamin D, and concentrations can vary significantly between and within species. The need for vitamin Dfortified foods (including via direct fortification and biofortification) to support the adequacy of vitamin D status is a corollary of several limitations to synthesise vitamin D from sunlight. Ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) can be found in some mushrooms and animalderived foods, respectively. Evidence has shown vitamin D3 is more effective than vitamin D2 at raising 25(OH)D blood concentrations. The vitamin D metabolite, 25(OH)D3, is present in animal-derived foods (e.g. meat, eggs and fish), and several intervention trials have shown 25(OH)D3 to be more effective at raising blood 25(OH)D concentrations than vitamin D3. In addition, 25(OH)D3 supplements may prove to be preferable to vitamin D3 for patients with certain clinical conditions. However, there is limited evidence on the effects of 25(OH) D3-fortified foods on human vitamin D status and health, both in the general population and patients with certain conditions, and long-term randomised controlled trials are needed in this area

Pre-existing invasive fungal infection is not a contraindication for allogeneic HSCT for patients with hematologic malignancies: a CIBMTR study.

Patients with prior invasive fungal infection (IFI) increasingly proceed to allogeneic hematopoietic cell transplantation (HSCT). However, little is known about the impact of prior IFI on survival. Patients with pre-transplant IFI (cases; n=825) were compared with controls (n=10247). A subset analysis assessed outcomes in leukemia patients pre- and post 2001. Cases were older with lower performance status (KPS), more advanced disease, higher likelihood of AML and having received cord blood, reduced intensity conditioning, mold-active fungal prophylaxis and more recently transplanted. Aspergillus spp. and Candida spp. were the most commonly identified pathogens. 68% of patients had primarily pulmonary involvement. Univariate and multivariable analysis demonstrated inferior PFS and overall survival (OS) for cases. At 2 years, cases had higher mortality and shorter PFS with significant increases in non-relapse mortality (NRM) but no difference in relapse. One year probability of post-HSCT IFI was 24% (cases) and 17% (control, P&lt;0.001). The predominant cause of death was underlying malignancy; infectious death was higher in cases (13% vs 9%). In the subset analysis, patients transplanted before 2001 had increased NRM with inferior OS and PFS compared with later cases. Pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT but significant survivorship was observed. Consequently, pre-transplant IFI should not be a contraindication to allogeneic HSCT in otherwise suitable candidates. Documented pre-transplant IFI is associated with lower PFS and OS after allogeneic HSCT. However, mortality post transplant is more influenced by advanced disease status than previous IFI. Pre-transplant IFI does not appear to be a contraindication to allogeneic HSCT

Effect of cucumber consumption on plasma creatinine, urea, uric acid and glucose level in apparently healthy students of college of health sciences, Nnamdi Azikiwe university, Nnewi campus, Anambra state, Nigeria

This study was designed to investigate the effect of oral intake of cucumber on plasma creatinine (Cr), urea, uric acid (Ua) and blood glucose in young apparently healthy students. A total of 29 subjects (14 males and 15 females) were recruited. Each subject was advised to abstain from cucumber and similar vegetables consumption for two weeks. Thereafter, they received 400 g of whole cucumber for 21days prior to their daily breakfast. 5mls each of baseline (day zero) and post consumption (day 22) samples were collected after overnight fast into fluoride oxalate and lithium heparin containers for glucose and other biochemical parameters respectively. Plasma glucose, urea, creatinine and uric acid were analyzed using standard methods. There was a significant decrease in the mean plasma glucose level in post cucumber consumption when compared to the pre-cucumber consumption (4.280.46 vs 4.680.35; p&lt;0.05). However, plasma levels of urea, uric acid and creatinine did not differ significantly between pre and post–cucumber consumption. This study revealed hypoglycaemic effect of cucumber consumption with no harmful effect on the kidney. Therefore, cucumber consumption could be of importance in prevention and management of diabetes mellitus. . Keywords: Cucumber, urea, glucose, Uric acid, Creatinine