A Missing Key to Understand the Electrical Resonance and the Mechanical Property of Neurons: a Channel-Membrane Interaction Mechanism

The recent study of the interaction between the fatty acyl tails of lipids and the K+ channel establishes the connection between flexoelectricity and the ion channel's dynamics, named Channel-Membrane Interaction (CMI), that may solve the electrical resonance in neurons

Association between physical activity and body fat percentage, with adjustment for BMI:a large cross-sectional analysis of UK Biobank

Objectives The objective of this study was to examine if, in the general population, physically active adults have less body fat after taking body mass index (BMI) into account. Design A cross-sectional analysis of participants recruited into UK Biobank in 2006–2010. Setting UK Biobank assessment centres throughout the UK. Participants 119 230 men and 140 578 women aged 40–69 years, with complete physical activity information, and without a self-reported long-term illness, disability or infirmity. Exposures Physical activity measured as excess metabolic equivalent (MET)-hours per week, estimated from a combination of walking, and moderate and vigorous physical activity. BMI from measured height and weight. Main outcome measure Body fat percentage estimated from bioimpedance. Results BMI and body fat percentage were highly correlated (r=0.85 in women; r=0.79 in men), and both were inversely associated with physical activity. Compared with <5 excess MET-hours/week at baseline, ≥100 excess MET-hours/week were associated with a 1.1 kg/m2 lower BMI (27.1 vs 28.2 kg/m2) and 2.8 percentage points lower body fat (23.4% vs 26.3%) in men, and 2.2 kg/m2 lower BMI (25.6 vs 27.7 kg/m2) and 4.0 percentage points lower body fat (33.9% vs 37.9%) in women. For a given BMI, greater physical activity was associated with lower average body fat percentage (for a BMI of 22.5–24.99 kg/m2: 2.0 (95% CI 1.8 to 2.2), percentage points lower body fat in men and 1.8 (95% CI 1.6 to 2.0) percentage points lower body fat in women, comparing ≥100 excess MET-hours per week with <5 excess MET-hours/week). Conclusions In this sample of middle-aged adults, drawn from the general population, physical activity was inversely associated with BMI and body fat percentage. For people with the same BMI, those who were more active had a lower body fat percentage

Tibetan sheep have a high capacity to absorb and to regulate metabolism of SCFA in the rumen epithelium to adapt to low energy intake

The nutritional intake of Tibetan sheep on the harsh Qinghai-Tibetan Plateau is often under maintenance requirements, especially during the long, cold winter. However, they have adapted well and even thrive under these conditions. The aim of the present study was to gain insight into how the rumen epithelium of Tibetan sheep has adapted to the consumption of low-energy-level diets. For this purpose, we compared Tibetan and small-tailed Han sheep (n 24 of each breed, all wethers and 1 center dot 5 years of age), which were divided randomly into one of four groups and offered ad libitum diets of different digestible energy (DE) densities: 8 center dot 21, 9 center dot 33, 10 center dot 45 and 11 center dot 57 MJ DE/kg DM. The Tibetan sheep had higher rumen concentrations of total SCFA, acetate, butyrate and iso-acids but lower concentrations of propionate than small-tailed Han sheep. The Tibetan sheep had higher absorption capability of SCFA due to the greater absorption surface area and higher mRNA expression of the SCFA absorption relative genes than small-tailed Han sheep. For the metabolism of SCFA in the rumen epithelium, the small-tailed Han sheep showed higher utilisation of the ketogenesis pathway than Tibetan sheep; however, Tibetan sheep had greater regulation capacity in SCFA metabolism pathways. These differences between breeds allowed the Tibetan sheep to have greater capability of absorbing SCFA and better capacity to regulate the metabolism of SCFA, which would allow them to cope with low energy intake better than small-tailed Han sheep

Descriptive and Network Post-Occupancy Evaluation of the Urban Public Space through Social Media: A Case Study of Bryant Park, NY

In modern cities, urban public spaces, such as parks, gardens, plazas, and streets, play a big role in people’s social activities, physical activities, mental health, and overall well-being. However, the traditional post-occupancy evaluation (POE) process for public spaces such as large urban parks is extremely difficult, especially for long-term user experiences through observations, surveys, and interviews. On the other hand, social media has emerged as a major media outlet recording millions of user experiences to the public, which provides opportunities to inform how public space is used and perceived by users. Furthermore, unlike previous research that primarily presented descriptive characters of park programs, our study employs a network model to elucidate the interactive relationships and intensities among reported park elements, human activities, and experiences. This approach enables us to track the sources within the space that impact people’s perceptions, such as weather conditions, food options, and notable landmarks. The utilization of this network model opens avenues for future research to comprehensively investigate the factors shaping people’s perceptions in public open spaces. This study uses Bryant Park as an example and presents a new analytical framework, POSE (post-occupancy social media evaluation), to support long-term POE studies for large public spaces. Methods such as data automation, descriptive statistics, and social network analysis were used. The identification and quantification of meaningful park activities, scenes, and sentiments as well as their relationships will help optimize the design and management of park programs

DACT2 is frequently methylated in human gastric cancer and methylation of DACT2 activated Wnt signaling

Dapper, Dishevelled-associated antagonist of beta-catenin (DACT), is a key regulator of Wnt signaling pathway. The purpose of this study is to explore the epigenetic changes and the function of DACT2 in human gastric cancer (GC). Eight human gastric cancer cell lines, 167 cases of primary gastric cancer and 8 cases of normal gastric mucosa were involved in this study. In addition, methylation Specific PCR (MSP), semi-quantitative RT-PCR, colony formation assay, flow cytometry assay, siRNA, immunofluorescence techniques and xenograft mice models were employed. The results indicate that DACT2 is frequently methylated in human primary gastric cancer (55.7%), and that methylation of DACT2 is associated with lost or reduction in its expression (X-2 test, P&lt;0.01). We found that DACT2 expression was regulated by promoter region hypermethylation. Methylation of DACT2 is associated with tumor differentiation, invasion and intravascular cancerous emboli (X-2 test, P&lt;0.05, P&lt;0.05 and P&lt;0.05). In gastric cancer patients treated with 5-FU and cisplatin, the five-year survival rates are higher in DACT2 methylated cases. DACT2 inhibits cell proliferation, migration and invasion in gastric cancer cells and suppresses gastric cancer xenografts in mice. Restoration of DACT2 expression inhibits both canonical and noncanonical WNT signaling in SGC7901 cells. Restoration of DACT2 expression sensitized gastric cancer cells to paclitaxel and 5-FU. In conclusion, DACT2 is frequently methylated in human gastric cancer and DACT2 expression is silenced by promoter region hypermethylation. DACT2 suppressed gastric cancer proliferation, invasion and metastasis by inhibiting Wnt signaling both in vitro and in vivo.OncologySCI(E)[email protected]; [email protected]

Tailoring sub-3.3 angstrom ultramicropores in advanced carbon molecular sieve membranes for blue hydrogen production

Carbon molecular sieve (CMS) membranes prepared by carbonization of polymers containing strongly size-sieving ultramicropores are attractive for high-temperature gas separations. However, polymers need to be carbonized at extremely high temperatures (900&deg; to 1200&deg;C) to achieve sub-3.3 &Aring; ultramicroporous channels for H2/CO2 separation, which makes them brittle and impractical for industrial applications. Here, we demonstrate that polymers can be first doped with thermolabile cross-linkers before low-temperature carbonization to retain the polymer processability and achieve superior H2/CO2 separation properties. Specifically, polybenzimidazole (PBI) is cross-linked with pyrophosphoric acid (PPA) via H bonding and proton transfer before carbonization at &le;600&deg;C. The synergistic PPA doping and subsequent carbonization of PBI increase H2 permeability from 27 to 140 Barrer and H2/CO2 selectivity from 15 to 58 at 150&deg;C, superior to state-of-the-art polymeric materials and surpassing Robeson&rsquo;s upper bound. This study provides a facile and effective way to tailor subnanopore size and porosity in CMS membranes with desirable molecular sieving ability. &nbsp;</p

Looking under the hood: A comparison of techno-economic assumptions across national and global integrated assessment models

Integrated assessment models are extensively used in the analysis of climate change mitigation and are informing national decision makers as well as contribute to international scientific assessments. This paper conducts a comprehensive review of techno-economic assumptions in the electricity sector among fifteen different global and national integrated assessment models. Particular focus is given to six major economies in the world: Brazil, China, the EU, India, Japan and the US. The comparison reveals that techno-economic characteristics are quite different across integrated assessment models, both for the base year and future years. It is, however, important to recognize that techno-economic assessments from the literature exhibit an equally large range of parameters as the integrated assessment models reviewed. Beyond numerical differences, the representation of technologies also differs among models, which needs to be taken into account when comparing numerical parameters. While desirable, it seems difficult to fully harmonize techno-economic parameters across a broader range of models due to structural differences in the representation of technology. Therefore, making techno-economic parameters available in the future, together with of the technology representation as well as the exact definitions of the parameters should become the standard approach as it allows an open discussion of appropriate assumptions. © 2019 The Author

Body size, body composition, and physical activity in relation to breast cancer risk

Accurately characterising the associations between adiposity, physical activity, and breast cancer risk has been limited by measurement error and confounding. This thesis investigates risk factors for breast cancer, with a focus on body size, body composition, and physical activity, within the UK Biobank, a new prospective cohort with comprehensive assessment of baseline characteristics, direct measures of body fat, and objectively-measured physical activity, which has the potential to address and overcome major limitations of prior studies. To characterise the patterns of association for breast cancer risk factors in UK Biobank, prospective analyses were conducted in up to 255,083 women. A total of 4,522 women were diagnosed with breast cancer during a mean 5.8 years follow-up. Associations between established risk factors and breast cancer incidence were consistent with prior studies. All measures of adiposity showed similar cross-sectional associations with self-reported physical activity, which were further investigated using objective, accelerometer measures of physical activity that were available on a subset of 42,992 women in the analyses, 3-5 years after end of recruitment. Compared to the non-linear associations seen with self-reported physical activity, accelerometer-measured physical activity showed nearly twofold larger, inverse, linear dose-response relationships with adiposity. To investigate whether the effect of genetic susceptibility, as measured by a genetic risk score (GRS) of 70 body mass index (BMI)-associated single nucleotide polymorphisms, on objectively measured BMI was modified by physical activity, cross-sectional analyses of GRS and BMI were performed by physical activity level. Comparing the top to bottom fifth of GRS, the most inactive participants had a 2.23 kg/m2 higher BMI while the most active participants had only a 1.33 kg/m2 higher BMI. The results using accelerometer rather than self-reported physical activity provided stronger evidence that genetic predisposition to adiposity can be largely overcome by greater physical activity. Prospective analyses of various indices of adiposity and breast cancer risk were performed to assess whether any were better predictors of risk, among women who were not current users of hormone replacement therapy. Women in the top compared to bottom quartile of body fat mass were at a 70% increased risk of breast cancer (relative risk (RR) 1.70; 95% confidence interval (CI) 1.52-1.90). All measures of body size and composition showed similar associations with breast cancer risk, suggesting impedance measures of fat were not substantially better indicators of risk than anthropometric measures. After adjusting for body fat mass, central adiposity was no longer associated with breast cancer risk. Physical activity was inversely associated with risk in both pre- and postmenopausal women. Adjusting for body fat mass slightly strengthened the inverse association in premenopausal women (RR 0.79; 95% CI 0.65-0.95) and attenuated the association in postmenopausal women (RR 0.84; 95% CI 0.72-0.97), per 5 milli-gravity of accelerometer-based physical activity, suggesting that the remaining protective association may be mediated by non-adiposity related factors. In conclusion, all indices of adiposity were similarly associated with physical activity, and associations were stronger with physical activity measured by accelerometer compared to questionnaire. Physical activity was an effect modifier of genetic susceptibility to adiposity. Adiposity was associated with increased breast cancer risk in postmenopausal women and physical activity was associated with reduced breast cancer risk in both pre- and postmenopausal women. The mechanisms underlying the protective association between physical activity and breast cancer risk are not entirely explained by adiposity and remain unclear.</p