Proton block and voltage gating are potassium-dependent in the cardiac leak channel Kcnk3.

Potassium leak conductances were recently revealed to exist as independent molecular entities. Here, the genomic structure, cardiac localization, and biophysical properties of a murine example are considered. Kcnk3 subunits have two pore-forming P domains and unique functional attributes. At steady state, Kcnk3 channels behave like open, potassium-selective, transmembrane holes that are inhibited by physiological levels of proton. With voltage steps, Kcnk3 channels open and close in two phases, one appears to be immediate and one is time-dependent (tau = approximately 5 ms). Both proton block and gating are potassium-sensitive; this produces an anomalous increase in outward flux as external potassium levels rise because of decreased proton block. Single Kcnk3 channels open across the physiological voltage range; hence they are "leak" conductances; however, they open only briefly and rarely even after exposure to agents that activate other potassium channels

Influence of gender preference and sex composition of surviving children on childbearing intention among high fertility married women in stable union in Malawi

Background: Child’s gender preference (GP) frequently leads to high fertility which has adverse effect on family health. The link between women’s fertility intention, GP and Living Children’s Sex Composition (LCSC) as found in this study is less explored in Malawi.Objectives: We examined the relationship between GP, LCSC and fertility intention.Methods: This study utilized 2010 MDHS dataset and focused on married women aged 15-49 years (n=1739) in stable unions who currently have at least 5 living children. Data was analyzed at bivariate and multivariate levels (α=0.05).Results: About 39.7% of the women have GP and higher proportion (23.3%) has preference for females. Age, region, wealth-quintile, religion, residence and family planning programmes were significantly associated with fertility intention. Women who have GP and same LCSC were 1.35 and 2.4 times significantly more likely to have intention to bear more children than those who have no GP and different sexes composition respectively. These odd ratios changed to 1.38 for GP and 2.44 for LCSC after adjusting for other socio-demographic variables.Conclusions: We find that GP and LCSC significantly influence women’s intention to bear more children. Women should stop childbearing after attaining their desired number irrespective of the LCSC.Keywords: Fertility intention, Gender preference, Children sex composition, High fertility married wome

Hidden correlation between absorption peaks in achiral carbon nanotubes and nanoribbons

This is the final version. Available on open access from Elsevier via the DOI in this recordIn this paper we study the effect of absorption peak correlation in finite length carbon nanotubes and graphene nanoribbons. It is shown, in the orthogonal {\pi}-orbital tight-binding model with the nearest neighbor approximation, that if the ribbon width is a half of the tube circumference the effect takes place for all achiral ribbons (zigzag, armchair and bearded), and corresponding tubes, starting from lengths of about 30 nm. This correlation should be useful in designing nanoribbon-based optoelectronics devices fully integrated into a single layer of graphene.This work was supported by the EU FP7 ITN NOTEDEV (Grant No. FP7-607521), EU H2020 RISE project CoExAN (Grant No. H2020-644076), FP7 IRSES projects CANTOR (Grant No. FP7-612285), QOCaN (Grant No. FP7-316432), InterNoM (Grant No. FP7-612624); Graphene Flagship (Grant No. 604391) and partially by the Belarus state program of scientific investigations “Convergence-2020”

Testing Ecological Theory with Lianas

Lianas constitute a diverse polyphyletic plant group that is advancing our understanding of ecological theory. Specifically, lianas are providing new insights into the mechanisms that control plant distribution and diversity maintenance. For example, there is now evidence that a single, scalable mechanism may explain local, regional, and pan‐tropical distribution of lianas, as well as the maintenance of liana species diversity. The ability to outcompete trees under dry, stressful conditions in seasonal forests provides lianas a growth advantage that, over time, results in relatively high abundance in seasonal forests and low abundance in aseasonal forests. Lianas may also gain a similar growth advantage following disturbance, thus explaining why liana density and diversity peak following disturbance at the local, forest scale. The study of ecology, however, is more than the effect of the environment on organisms; it also includes the effects of organisms on the environment. Considerable empirical evidence now indicates that lianas substantially alter their environment by consuming resources, suppressing tree performance, and influencing emergent properties of forests, such as ecosystem functioning, plant and animal diversity, and community composition. These recent studies using lianas are transcending classical tropical ecology research and are now providing novel insights into fundamental ecological theory

Release of obstructing rectal cuff following transanal endorectal pullthrough for Hirschsprung’s disease: a laparoscopic approach

Obstructive problems secondary to a tight or a long rectal cuff following transanal endorectal pullthrough for Hirschsprung’s disease usually require redo surgery for release. Many approaches have been described. We describe the laparoscopic approach for the release of a tight or a long rectal cuff in two cases after a transanal endorectal pullthrough. Two patients had obstructive symptoms after transanal endorectal pullthrough for Hirschsprung’s disease. The first patient had a long rectal cuff that caused severe constipation with severe straining on defecation and the second patient had recurrence of symptoms with failure of spontaneous defecation with the need for an enema or a rectal tube for evacuation. A laparoscopic excision of the long rectal cuff was performed in the first patient and incision of the tight rectal cuff in the second patient. In both patients, the obstructing symptoms were because of a rectal cuff that was long in the first case and tight in the second. The procedure was completed laparoscopically with relief of symptoms and acquisition of normal defecation immediately after surgery. Approach of the rectal cuff was possible using laparoscopy and this technique facilitates release or excision of the rectal cuff when it causes obstructing symptoms without the need for extensive surgery and without the risk of causing fecal incontinence or wound disruption or infection using other more complicated techniques. Keywords: Hirschshprung, laparoscopy, obstruction, rectal cuf

A Trial of a 7-Valent Pneumococcal Conjugate Vaccine in HIV-Infected Adults.

BACKGROUND: Streptococcus pneumoniae is a leading and serious coinfection in adults with human immunodeficiency virus (HIV) infection, particularly in Africa. Prevention of this disease by vaccination with the current 23-valent polysaccharide vaccine is suboptimal. Protein conjugate vaccines offer a further option for protection, but data on their clinical efficacy in adults are needed. METHODS: In this double-blind, randomized, placebo-controlled clinical efficacy trial, we studied the efficacy of a 7-valent conjugate pneumococcal vaccine in predominantly HIV-infected Malawian adolescents and adults who had recovered from documented invasive pneumococcal disease. Two doses of vaccine were given 4 weeks apart. The primary end point was a further episode of pneumococcal infection caused by vaccine serotypes or serotype 6A. RESULTS: From February 2003 through October 2007, we followed 496 patients (of whom 44% were male and 88% were HIV-seropositive) for 798 person-years of observation. There were 67 episodes of pneumococcal disease in 52 patients, all in the HIV-infected subgroup. In 24 patients, there were 19 episodes that were caused by vaccine serotypes and 5 episodes that were caused by the 6A serotype. Of these episodes, 5 occurred in the vaccine group and 19 in the placebo group, for a vaccine efficacy of 74% (95% confidence interval [CI], 30 to 90). There were 73 deaths from any cause in the vaccine group and 63 in the placebo group (hazard ratio in the vaccine group, 1.18; 95% CI, 0.84 to 1.66). The number of serious adverse events within 14 days after vaccination was significantly lower in the vaccine group than in the placebo group (3 vs. 17, P=0.002), and the number of minor adverse events was significantly higher in the vaccine group (41 vs. 13, P=0.003). CONCLUSIONS: The 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine serotypes or serotype 6A. (Current Controlled Trials number, ISRCTN54494731.) Copyright 2010 Massachusetts Medical Society