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Degradation of kinetically bulk heterojunction film morphology in organic solar cells is a grand challenge for their practical application. Here, the authors design and synthesise multicomponent photoactive material by facile one-pot polymerization and achieve efficiency of 11.8% and T80 of 1000 h.

Abstract Polythiophenes, built on head‐to‐head (HH) linked 3,3′‐oligomer ethylene glycol‐2,2′‐bithiophene (gT2), have simple chemical structure, good backbone planarity, and relatively high‐lying the lowest unoccupied molecular orbital (LUMO) energy levels, hence showing excellent p‐type performance in organic electrochemical transistors (OECTs) with µC* of several hundred F cm−1 V−1 s−1. In this study, sequential cyano substitution is utilized to enable transformation of charge carrier polarity from p‐type to n‐type in OECTs, based on the parent polythiophene g4T2‐T2. With the increase of cyano group number, the polythiophenes exhibit gradually lowered LUMO levels from −2.55 to −3.90 eV. As a result, from g4T2‐T2 to CNg4T2‐CNT2, the p‐type performance dramatically diminishes accomplished by the enhancement of n‐type one when applied in OECTs. To the authors' delight, polymer CNg4T2‐CNT2 with the highest content of cyano groups exhibits a remarkable n‐type µC* of 27.01 F cm−1 V−1 s−1 and high gm,norm of 6.75 S cm−1 with negligible p‐type character. This study demonstrates that sequential cyano substitution provides a powerful approach for developing high‐performance n‐type polymers for OECT applications.

Abstract n‐Doped polymers with high electrical conductivity (σ) are still very scarce in organic thermoelectrics (OTEs), which limits the development of efficient organic thermoelectric generators. A series of fused bithiophene imide dimer‐based polymers, PO8, PO12, and PO16, incorporating distinct oligo(ethylene glycol) side‐chain to optimize σ is reported here. Three polymers show a monotonic electron mobility decrease as side‐chain size increasing due to the gradually lowered film crystallinity and change of backbone orientation. Interestingly, polymer PO12 with a moderate side‐chain size delivers a champion σ up to 92.0 S cm−1 and a power factor (PF) as high as 94.3 µW m−1 K−2 in the series when applied in OTE devices. The PF value is among the highest ones for the solution‐processing n‐doped polymers. In‐depth morphology studies unravel that the moderate crystallinity and the formation of 3D conduction channel derived from bimodal orientation synergistically contribute to high doping efficiency and large charge carrier mobility, thus resulting in high performance for the PO12‐based OTEs. The results demonstrate the great power of simple tuning of side chain in developing n‐type polymers with substantial σ for improving organic thermoelectric performance.

Introduction: Non-adherence to antihypertensive medications is a leading cause of uncontrolled hypertension and its complications. However, data on the factors associated with non-adherence to antihypertensive medications in the communities of Sarawak, Malaysia, are limited. This study aimed to examine the prevalence and determinants of medication non-adherence among patients with uncontrolled hypertension. Methods: A cross-sectional study was conducted using the systematic sampling method in four government primary healthcare clinics in Sarawak. A self-administered questionnaire was used to obtain socio-demographic data and evaluate non-adherence. Blood pressure was measured, and relevant clinical variables were collected from medical records. Multivariate logistic regression was used to determine the determinants of medication non-adherence. Results: A total of 488 patients with uncontrolled hypertension were enrolled in this study. The prevalence of medication non-adherence was 39.3%. There were four predictors of medication non-adherence among the patients with uncontrolled hypertension: tertiary educational level (odds ratio [OR]=4.21, 95% confidence interval [CI]=1.67–10.61, P=0.010), complementary alternative medication (OR=2.03, 95% CI=1.12–3.69, P=0.020), non-usage of calcium channel blockers (OR=1.57, 95% CI=1.02–2.41, P=0.039) and 1 mmHg increase in the systolic blood pressure (OR=1.03, 95% CI=1.00–1.05, P=0.006). Conclusion: Because of the high prevalence of medication non-adherence among patients with uncontrolled hypertension, primary care physicians should be more vigilant in identifying those at risk of being non-adherent. Early intervention should be conducted to address non-adherence for blood pressure control.

Summary: Two wide band-gap copolymers poly[4,8-bis(5-(2-butylhexylthio)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl-alt-TZNT] (PBDTS-TZNT) and poly[4,8-bis(4-fluoro-5-(2-butylhexylthio)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl-alt-TZNT] (PBDTSF-TZNT) based on naphtho[1,2-c:5,6-c]bis(2-octyl-[1,2,3]triazole) (TZNT) and benzo[1,2-b:4,5-b']dithiophene (BDT) with different conjugated side chains have been developed for efficient nonfullerene polymer solar cells (NF-PSCs). The rigid planar backbone of BDT and TZNT units imparted high crystallinity and good molecular stacking property to these copolymers. Using 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone)-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]-dithiophene (ITIC) as the acceptor, PBDTSF-TZNT devices showed a high Voc of 0.98 V with an Eloss of 0.61 eV. On selecting 3,9-bis(2-methylene-(5,6-difluoro-(3-(1,1-dicyanomethylene)-indanone)-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b’]-dithiophene (IT-4F) instead of ITIC, the devices maintained the high Voc of 0.93 V with an even lower Eloss of 0.59 eV. The combination of the above-mentioned low Eloss, broadened absorption, better matched energy level, improved crystallinity, and fine-tuned morphology promoted the power conversion efficiency (PCE) of PBDTSF-TZNT:IT-4F devices from 12.16% to 13.25%. Homo-tandem devices based on PBDTSF-TZNT:IT-4F subcells further enhanced the light-harvesting ability and boosted the PCE of 14.52%, which is the best value for homo-tandem NF-PSCs at present. : Chemical Synthesis; Energy Materials; Devices Subject Areas: Chemical Synthesis, Energy Materials, Devices

To investigate the prevalence of general and abdominal obesity and associated factors in Bouyei and Han peoples.A cross-sectional study was carried out in Guizhou province, southwest China in 2012, with multi-stage sampling to enroll 4551 participants aged 20 to 80 years. General and abdominal obesity were defined by World Health Organization (WHO) for Chinese. A design-based analysis was performed to evaluate prevalence of obesity and its related factors.Bouyei people had a significantly lower prevalence of general obesity (4.8% vs. 10.9%, p < 0.05) and abdominal obesity (13.6% vs. 26.8%, p < 0.05) than that in Han people. Prevalence of obesity increased with age until middle-age period and declined thereafter. Men aged 40-49 years group and women aged 50-59 years group have the highest prevalence of general obesity. Prevalence of abdominal obesity was higher than that of general obesity. Middle-age, Higher income, Han people were significantly associated with an increased risk of General/abdominal obesity.Bouyei people had a lower prevalence of general and abdominal obesity than the Han people. Etiological studies should be conducted to determine underlying genetic factors and dietary factors.

El presente estudio contempló el seguimiento dinámico y el estudio de la hidroquímica del agua superficial y del agua subterránea poco profunda en la parte norte del delta del río Amarillo, China. El análisis del agua superficial y el agua subterránea poco profunda reveló que el agua subterránea poco profunda se exhibía en dos formas: tipo de evaporación por precipitación y tipo hidrológico, y este último fue obviamente afectado por el nivel dinámico del agua del río Amarillo. El agua superficial y el agua subterránea poco profunda exhibieron un mayor grado de mineralización. Los cationes de Mg2+, Na+ y K+ y los aniones de Cl- y SO42- fueron los principales componentes iónicos del total de sólidos disueltos. El tipo hidroquímico de agua subterránea poco profunda era Cl-Na·K que era una forma típica de agua de mar o salmuera. El tipo químico del agua del agua superficial cambió a Cl·SO4-Na·K·Ca debido a la contaminación industrial, agrícola y urbana. La calidad general del agua superficial era mala y se encontró que estaban presentes los principales índices de contaminación, excepto el cianuro. Los niveles de DQO y flúor excedieron los valores estándar en el agua superficial. La calidad del agua subterránea fue mala, pues se detectaron la mayoría de los contaminantes, excepto cianuro y fenol volátil. Ocho índices excedieron los niveles estándar de calidad del agua subterránea, incluidos Cl-, Na+, dureza total, DQO, NH4+, Hg, As, NO3-, Cl- y Na+. La contaminación de las aguas superficiales y subterráneas fue causada principalmente por la descarga de aguas residuales de la industria petrolera, química y de salmuera; contaminación de fuentes agrícolas difusas; fugas de fosas sépticas y tuberías de alcantarillado en áreas urbanas y rurales; y agua de lluvia que se mezcla con la lixiviación de las pilas de basura. Para mejorar la calidad del agua es necesario optimar el control y la gestión de las aguas residuales, y reconsiderar el diseño industrial.

MXenes are a class of two-dimensional inorganic materials comprising transition-metal carbides, nitrides, or carbonitrides of several atomic layers thick. Their general formula is (Mn+1XnTx), where M is a transition metal, such as Ti, n is the number of atomic layers, X is carbon and/or nitrogen, and Tx is the functional group introduced in the reaction process, such as OH, H, or F. They are obtained from the MAX precursor (Mn+1AXn, where A is a group of 13 or 14 elements, such as Al and Si). In 2011, Gogotsi, Barsoum, et al. first reported the synthesis of Ti3C2Tx by selective etching of the Al layer using a Ti3AlC2 MAX phase precursor impregnated with HF solution. The advantageous properties of MXenes, such as large specific surface area, fast charge–discharge performance, and small volume change, have made them attractive for lithium-ion battery anode materials, as first reported by the group Simon and Gogotsi in 2012. Since then, much attention has been paid to MXenes. Researchers hope to use MXenes for lithium-ion battery anode materials with high capacity, high safety, and improved energy density and battery life. However, a multilayer MXene material will collapse or accumulate during the preparation process, resulting in a large reduction in the contact area, thus reducing the electron and ion transport capacity of the MXene material perpendicular to the layer structure. Hence, MXenes are usually combined with other materials to improve the obtained structure, expand the layer spacing, and help enhance their electrochemical properties. This paper reviews the approaches to improving the electrochemical properties of MXenes by doping with transition-metal oxides, transition-metal sulfides, and silicon, as well as the scheme to achieve a stable and dendrite-free metal anode by using MXenes and high-capacity anode materials. Last, future challenges faced by MXenes as anode materials for lithium-ion batteries are analyzed and prospected.