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• A PCE over the 13% for ternary PSCs based on ternary polymer donor was achieved. • Morphology studies confirmed that ternaty PSC brought most appropriate phase separation. • A classical ternary strategy could significantly improve charge extraction. The third component played an increasingly significant role in polymer solar cells (PSCs), especially for the morphological impact. Here, we use a ternary polymer donor (TBFCl50-BDD) and organic small molecule acceptor (BTP-4F) as the main material and introduce a third component (PC 71 BM) to enhance the morphology of the photoactive layer and result in improved device performance. The TBFCl50-BDD:BTP-4F based PSCs only exhibited an efficiency of 10.58%, while The power conversion efficiency of ternary device (TBFCl50-BDD:BTP-4F:PC 71 BM) reached 13.15%. Importantly, the introduction of PC 71 BM can not only improve the morphology of the active layer and promote more efficient exciton transport, but also influence the molecular arrangement for better crystallization performance. This work offers an effective method for optimization of the morphology to enhance the properties of PSCs. [ABSTRACT FROM AUTHOR]

• A halogen-free additive, dibenzyl ether, was successfully introduced into PSCs. • The dibenzyl ether additive could boost the phase composition distribution. • The morphology, exciton dissociation, charge transport ability can be improved. Conventional additives like 1,8-diiodooctane (DIO) and 1-chloronaphthalene (CN) play an essential role in optimization of blend film morphology of polymer solar cells (PSCs). However, they have halogenated elements in their end groups, which are harmful to the environment and humans, limiting large-scale applications. In this work, a novel non-toxic and non-halogen additive, dibenzyl ether (DE), was introduced into PTB7-Th:PC 71 BM based PSCs, and the role of the DE additive was systemically investigated. The results showed that DE additive can not only adjust phase separation and optimize the morphology of blend film, but also promote the mobility of hole and electron. The grazing-incidence small-angle X-ray scattering (GISAXS) showed that the introduction of DE increased the interface area between PTB7-Th and PC 71 BM, which can promote exciton dissociation, and achieve better charge transport. Transient photovoltage (TPV) and transient photocurrent (TPC) measurements show that carrier recombination of the additive-containing devices can be effectively inhibited with improved charge transport efficiency of the active layer. Consequently, the devices with DE additive achieve power conversion efficiency (PCE) of 9.53% and a fill factor (FF) of 70.41%. Our non-toxic and non-halogen additive provides a potential solution for the preparation of environmental-friendly PSCs in the future. [ABSTRACT FROM AUTHOR]

Valsalva maneuver is a recognized treatment for supraventricular tachycardia, but in clinical setting it has a low chance to achieve successful cardioversion. Studies suggested that the postural modification of valsalva maneuver may improve the rate of cardioversion. We further modified the maneuver and conduct a multicenter randomized controlled trial to test its efficacy. Appelboam A, Reuben A, Mann C, et al. Postural modification of the standard Valsalva maneuver for emergency treatment for supraventricular tachycardias (REVERT): a randomized controlled trial. Lancet 2015; 386 (10005):1747–53 1. Allison Michaud, PhD, Eddy Lang. Leg lift Valsalva maneuver for treatment of supraventricular tachycardias. CJEM 2017; 19(3):235–237 2. To verify the efficacy of the modified Valsalva maneuver in SVT in Chinese population and simplify the operation process further. [ABSTRACT FROM AUTHOR]

Abstract To prove the theory that meteorological factors, especially winter drying events, usually affect trees by inducing water and energy imbalance, systematic studies of winter drying damage to Ligustrum lucidum trees in Shandong, China in 2018 were performed by analyzing digital and thermal images of the trees and integrating the results with meteorological and geostatistical analysis and the results of osmotic stress tests in saturated sucrose solution. The results indicate that sap water can not only be transported upward with assistance from cohesion-tension force, but also can be turned back from the terminals of leaves and branches under the inverse pulling force. Under extreme conditions during winter drying events, the breakage of sap water column and reduction of the terminal tissues or organs occur. Similar "∧"-shaped leaf symptoms can also be induced by freezing, summer drought and osmotic stress. The results support the theory of transpiration surface reduction characterized by unity of freezing and drying. Therefore, severe damage to juvenile plants of Ligustrum lucidum under these conditions may be caused by the combined effects of low temperature, drought, strong irradiation and saline soil as well as by the sensitive status of the plants. Highlights • Winter drying injury of Ligustrum lucidum associating with water and energy imbalance. • Digital and thermo images analysis, meteorological indices and geo-statistical analysis. • Sap water can turn back from the terminal of leaves and branches. • At the extreme situation transpiration reduction of the terminal tissue or organ occur. • Similar "∧"shaped symptoms can be induced by freezing, summer drought and osmotic stress. [ABSTRACT FROM AUTHOR]

Abstract Traffic noise pollution is a widespread public health problem in both developing and developed countries. Quickly and effectively evaluating the quality of an urban acoustic environment is an important challenge for urban planning and management. To solve this problem, this study first classified the urban function area of the study area according to the functional characteristics and environmental quality requirements of the region, and then, the traffic noise propagation model was applied to predict instantaneous sound levels (L A) based on noise attenuation. Finally, a traffic noise evaluation model was proposed to evaluate the quality of the urban acoustic environment. Taking Changchun city as our study area, eighty field samples of equivalent noise levels ( L eq ) were measured every ten minutes at four types of roads, classified as trunk roads, secondary roads, expressways and rural roads, in different urban function areas. An urban noise map was drawn to reflect the degree of traffic noise pollution. By comparing the measured and predicted values of noise levels, the results show that the traffic noise propagation model can be used to predict instantaneous sound levels. The traffic noise evaluation results show that the quality of the acoustic environment in our study area was at a medium level, which means that long-term exposure to it can affect the normal work and life of people. The traffic noise propagation model and proposed evaluation model are feasible methods for evaluating the quality of the acoustic environment and can provide a reference for the management of noise pollution control of urban traffic. [ABSTRACT FROM AUTHOR]

Ferroelectric BaTiO 3 thin films were epitaxially grown on rutile-TiO 2 buffered GaAs(001) substrates by pulsed laser deposition system. The in-plane relationship of this heterostructure is 〈110〉BaTiO 3 //〈001〉TiO 2 //〈110〉GaAs and the out-plane relationship is BaTiO 3 (110)//TiO 2 (110)//GaAs(001). The surface of BaTiO 3 is flat and the interfaces between each layer are clear. The oxygen vacancies were eliminated by ex-situ annealing in adequate O 2 . In short, a highly (110)-oriented BaTiO 3 thin film was grown on TiO 2 buffered GaAs (001) substrate with excellent electrical and structural properties. The BaTiO 3 (150 nm)/TiO 2 (40 nm)/GaAs system demonstrates hysteresis loops with a remnant polarization of 2.6 μC/cm 2 and a small leakage current density of 1 × 10 − 6 A/cm 2 both at 300 kV/cm. [ABSTRACT FROM AUTHOR]

Ecological vulnerability assessment is a key approach to adaptation to and mitigation of environmental degradation. To assess the ecological vulnerability of Yinma River Basin in cold mountain region of China, the ecological vulnerability index (EVI) model was established based on the integrated system dynamic (SD) model and driving force-pressure-state-impact-response-management (DPSIRM) framework. Using multi-sources data including meteorological, remote sensing, basic geographical, sample and socio-economic data, the values of EVI were calculated. The assessment results indicated that the overall ecosystem vulnerability conditions in the study area experienced a degenerating trend. The extremely, heavily and moderately vulnerable zones were mainly distributed in the north-central and southwest parts of the basin. The slightly and lightly vulnerable areas were distributed in the southeast part of the basin. For the distribution of ecological vulnerability grades, in administrative regions, the high rate of slightly vulnerable level and light vulnerable level appeared in Shuangyang district and Panshi city while the largest area rate of moderately, heavily and extremely vulnerable level were distributed in Dehui city, Nongan county, Jiutai district and Yitong county. The study demonstrated that the SD model could efficiently reflect the dynamic mechanism of the basin ecological vulnerability and the results gained closely reflected the reality of the study area. [ABSTRACT FROM AUTHOR]

We consider a general parabolic category O S over symmetrizable Kac-Moody algebras. We introduce a reduction rule of hom-spaces between parabolic Verma modules over different Kac-Moody algebras which yield some applications on parabolic Verma module homomorphisms. [ABSTRACT FROM AUTHOR]

Background: Catheter ablation of persistent atrial fibrillation (AF) is associated with longer procedure times and lower long-term success rates than that of paroxysmal AF. Objective: To test the hypothesis that restoration/maintenance of sinus rhythm (SR) preablation would facilitate AF termination and improve outcomes in patients with persistent AF. Methods: We conducted a 2-group cohort study of consecutive patients with persistent AF and SR restored for at least 1 month prior to ablation (SR group; n = 40) and controls matched by age, sex, and AF duration (control group; n = 40). Radiofrequency stepwise catheter ablation was performed in AF for both groups (induced and spontaneous, respectively). Success was defined as freedom from atrial tachyarrhythmia without antiarrhythmic drugs beyond 1 year of follow-up. Results: During the index ablation procedure, AF cycle length was longer in the SR group than in the control group (183 ± 32 ms vs 166 ± 20 ms; P = .06), suggestive of reverse remodeling. In the SR group, AF more frequently terminated during ablation (95.0% vs 77.5%; P <.05) and required less extensive ablation of complex fractionated electrograms (40.0% vs 87.5%; P <.001) and linear lesions (42.5% vs 82.5%; P <.001). Mean procedural (199.8 ± 69.8 minutes vs 283.5 ± 72.3 minutes; P <.001), fluoroscopy (51.0 ± 24.9 minutes vs 96.3 ± 32.1 minutes; P <.001), and radiofrequency energy delivery (47.5 ± 18.9 minutes vs 97.0 ± 30.6 minutes; P <.001) times were shorter in the SR group. Clinical success rates were similar between groups for first (55.0% vs 45.0%; P = .28) and last (80.0% vs 70.0%; P = .28) procedures, during similar follow-up periods (21.1 ± 9.7 months). Conclusions: Restoration of SR prior to catheter ablation for persistent AF whenever possible decreases the extent of ablation with the same high clinical efficacy. [ABSTRACT FROM AUTHOR]

Background: Termination of persistent atrial fibrillation (AF) is a valuable ablation endpoint but is difficult to anticipate. We evaluated whether temporal and spatial indices of AF regularization predict intraprocedural AF termination and outcome. Objective: The purpose of this study was to test whether temporospatial organization of AF after pulmonary vein isolation (PVI) predicts whether subsequent stepwise ablation will terminate persistent AF or predict outcome. Methods: In 75 patients with persistent AF, we measured AF cycle length (AFCL), temporal regularity index (TRI, a spectral measure of timing regularity), and spatial regularity index (SRI, cycle-to-cycle variations in spatial vector) between right atrial appendage and proximal and distal coronary sinus before and during stepwise ablation to the endpoint of AF termination. Results: AF termination was achieved in 59 patients (79%) by ablation. AF terminated during PVI in 11 patients, who were excluded from analysis. In the remaining 48 patients, TRI and SRI increased during stepwise ablation, as compared with 16 patients without termination (P<.05). AFCL was prolonged in both groups. From receiver operating characteristics analysis of the first 22 patients (training set), a post-PVI TRI increase predicted AF termination in the latter 42 patients (test set) with a positive predictive value of 96%, negative predictive value of 53%, sensitivity of 71%, and specificity of 91%. Results were similar for SRI. After 36 months, higher arrhythmia-free outcome was observed in patients in whom PVI caused temporospatial regularization in AF. Conclusions: Temporal and spatial regularization of persistent AF after PVI identifies patients in whom stepwise ablation subsequently terminates AF and prevents recurrence. [ABSTRACT FROM AUTHOR]

Objectives: We sought to determine whether atrial tachycardia arising adjacent to the noncoronary aortic sinus (NCAS-AT) has distinctive atrial activation patterns in relation to targeted anatomic imaging. Background: The knowledge of atrial activation patterns of the NCAS-AT and its anatomic basis is very limited. Methods: Three-dimensional electroanatomic mapping was performed during NCAS-AT in 13 patients and during sequentially pacing from the noncoronary aortic sinus (NCAS) and the para-Hisian atrial area in 15 reference patients. The spatial relationship between the NCAS and the contiguous atria was studied in another 25 reference patients using computed tomography and in 12 human hearts using gross and microscopic anatomic examination. Results: During NCAS-AT, the para-Hisian area of the right atrium (RA) and the anteroseptal region of the left atrium were activated almost simultaneously. The initial activation area (within first 20 ms of atrial depolarization) was relatively wide (9.3 ± 2.6 cm2 on the RA map and 8.1 ± 2.1 cm2 on the left atrium map). In reference patients, NCAS pacing reproduced a biatrial activation pattern of NCAS-AT and resulted in a wider initial activation area than the para-Hisian atrial pacing within first 20 ms of RA activation (10.1 ± 3.0 cm2 vs. 3.9±1.7 cm2; p < 0.001). Anatomically, the wall of NCAS did not contain myocardial tissue, but was intimately related to the paraseptal regions of the atria such that the shortest distances from the NCAS to the RA and the left atrium were 1.7 ± 0.6 mm and 2.3 ± 0.9 mm (p < 0.01), respectively. Conclusions: NCAS-AT has distinct atrial activation patterns that can be explained in part by its spatial anatomic relationship with the atria. [ABSTRACT FROM AUTHOR]

Summary: Atrial fibrillation (AF) and congestive heart failure (CHF) often coexist (AF–CHF), and each adversely affects the other with respect to management and prognosis. Therapy with antiarrhythmic drugs to maintain sinus rhythm was disappointing. Ablation is more successful than antiarrhythmic drug therapy for the prevention of AF with few complications, although in patients with AF–CHF it is noted. Ablating autonomic nerves and ganglia on the large vessels and the heart can result in AF suppression with little damage to healthy myocardium. Our study in patients with AF–CHF found that cardiac function aggravation was more frequent in patients with AF recurrence than that of those who successfully maintain sinus rhythm. The autonomic nervous system is a fine network spreading throughout the myocytes; hence the elimination of atrial vagal with radiofrequency catheter ablation can influence the innervation in sinus and AV nodes even in the ventricular region. Thus we propose that atrial vagal denervation may result in paratherapeutic sympathovagal imbalance in the ventricular region, which has a negative effect in a failing heart, although it is neutralized by the benefit accrued from sinus rhythm after successful ablation. [Copyright &y& Elsevier]

Summary: Adenosine deaminase (ADA) is an enzyme which catalyzes adenosine to inosine. Patients who inherently lack the enzyme have defects in both humoral and cellular immunity. ADA plays an important role in many immunity mediate diseases, such as asthma, Graves’ disease and tuberculosis. Coronary artery disease (CAD) has been considered as an inflammatory and immunizing disease recently. However, there are few reports about the effect of ADA in cardiovascular fields. In fact, ADA may play a key role in the immunity, inflammation and other aspects of CAD. This hypothesis is potentially based on three aspects of evolution. First, ADA inhibitors attenuate the elevation of proinflammatory factors, which shows ADA mediate in the inflammation response. ADA also has effect on the activation of complement system by the deamination of adenosine. Thus, ADA has a role in CAD by affecting inflammation process. Second, many effects produced by ADA are caused by the metabolism of adenosine. It is known that adenosine can inhibit the invasion of the neutrophil so as to attenuate the ischemic/reperfusion injury . Adenosine can increase coronary artery blood flow during active stress and hypoxia to balance the oxygen supply and demand. Adenosine can also account for the majority of basal vascular endothelial growth factor (VEGF) mRNA and protein expression in cultured myocardial vascular smooth muscle cells under normoxic conditions to stimulate the angiogenesis. If adenosine is rapidly metabolized by the high level of ADA, the advantages of adenosine will lost. Finally, adenosine is catalyzed to inosine, which can produce superoxide radicals and exaggerate the ischemic/reperfusion injury. In conclusion ADA can have a crucial role in CAD, if design and development of therapeutic strategies against ADA is guaranteed, an innovational therapeutic approach to CAD can be realized. [Copyright &y& Elsevier]

• Prolonged drought had a greater positive impact on pine caterpillar outbreaks than short-term drought. • Pine caterpillar outbreaks in Shandong Province predicted to decrease gradually to 2100. • Modeling scenarios differed with respect to latitudinal shifts in outbreaks. Drought is an important driver of forest pests, and reports of climate change are becoming more conspicuous as a result of enhanced drought. These projected changes have a positive impact on forest insect pests that result in substantial forest damage, adverse economic impacts, and losses of ecosystem resources. Therefore, we explored the impact of drought on the outbreak of pine caterpillars and predicted the future trend of pine caterpillar outbreaks under different emission scenarios by constructing a drought-pine caterpillar model (using a greenhouse gas emission scenario: Representative Concentration Pathways, RCP4.5 and RCP8.5 from 2016 to 2099). The results showed that: (1) Long-term or prolonged drought had a greater positive impact on pine caterpillar outbreaks than short-term drought; (2) The drought was more severe in the RCP 8.5 scenario than that in RCP 4.5; (3) The outbreaks of pine caterpillars in Shandong Province will gradually decrease approaching 2100 under the RCP4.5 and RCP8.5 scenarios. There is a trend of cyclical changes of approximately 30 years under the RCP4.5 scenario, while these changes primarily occurred before the 2050s and then decreased significantly and even became almost zero in the 2090s. (4) Under the two scenarios, light infestations comprised the largest area, followed by moderate and severe. Our study is important to promote the understanding of climate change and provide references and direction for forest managers. [ABSTRACT FROM AUTHOR]

Summary: The percutaneous invention of the catheter tip into heart chambers through an artery or vein is invasive and poses potential risks of infection and damaging blood vessels or normal heart tissue. The anterior aspect of the esophagus is always in direct contact with the posterior wall of the left atrium. A recent study found that high intensity focused ultrasound could create precise defects in different cardiac tissues without damage to the surrounding tissue. So we hypothesize transesophageal high intensity focused ultrasound ablation of left atrium posterior wall is a good noninvasive method for treating atrial fibrillation. [Copyright &y& Elsevier]

Summary: Atrial fibrillation (AF) is the most commonly occurring arrhythmia in clinical practice, however, the mechanism of atrial fibrillation is not well explained. It has been considered that myocardial fibrosis plays a role in atrial fibrillation. Within the heart, this fibrosis is thought to be mediated by transforming growth factor-β1 (TGF-β1), a potent stimulator of collagen-producing cardiac fibroblasts. Recent studies indicate that atrial fibrillation is associated with elevated serum concentrations of TGF-β1 and C-terminal propeptide of procollagen type I (a marker of collagen type I synthesis). TGF-β1 was not only associated with the presence of atrial fibrillation but may also predict patients at increased risk for future development of atrial fibrillation. Why TGF-β1 in atrial fibrillation is high is a puzzling problem. We hypothesized that TGF-β1 is a possible cause of atrial fibrillation by initiating fibrosis response. Atrial interstitial fibrosis has been seen in patients with CHF and in animal models of pacing-induced heart failure. It was demonstrated that TGF-β1 levels were increased in the atria after the development of congestive heart failure in dogs. In a similar study, mice with increased expression of TGF-β1 were prone to atrial fibrillation development as a result of raised levels of atrial fibrosis. If the hypothesis is confirmed, administration of TGF-β1 monoclonal antibodies may be used to eliminate the etiology. It will be a new target point to treat atrial fibrillation. [Copyright &y& Elsevier]

Clinical Question: Valsalva maneuver is a recognized treatment for supraventricular tachycardia, but in clinical setting it has a low chance to achieve successful cardioversion. Studies suggested that the postural modification of valsalva maneuver may improve the rate of cardioversion. We further modified the maneuver and conduct a multicenter randomized controlled trial to test its efficacy.Research in Context: Appelboam A, Reuben A, Mann C, et al. Postural modification of the standard Valsalva maneuver for emergency treatment for supraventricular tachycardias (REVERT): a randomized controlled trial. Lancet 2015; 386 (10005):1747-53 [1]. Allison Michaud, PhD, Eddy Lang. Leg lift Valsalva maneuver for treatment of supraventricular tachycardias. CJEM 2017; 19(3):235-237 [2].Objective: To verify the efficacy of the modified Valsalva maneuver in SVT in Chinese population and simplify the operation process further. [ABSTRACT FROM AUTHOR]

• The V 2 O 5 nanoparticles can fill the pinholes in PEDOT:PSS. • The hole transport layer of V 2 O 5 :PEDOT:PSS has high conductivity and hydrophobicity. • The crystallizability of the active layer is improved by adjusting the interface. • The PCE over 9.4% and FF over 70% can be achieved in OSCs with composite HTL. The fill factor (FF) as an important photovoltaic parameter is related to the property of transport layers and active layers for organic solar cells (OSCs). Herein, we propose a simple method to improve FF by using inorganic-organic composite hole transport layer (HTL) in OSCs. Through incorporating inorganic metal oxide, vanadium pentoxide (V 2 O 5) nanoparticles into PEDOT:PSS, the morphology and conductivity of the composite HTL are improved, due to V 2 O 5 nanoparticles can fill the pinholes in PEDOT:PSS and expose more PEDOT chains to the surface core–shell structure. The PTB7-Th:PC 71 BM-based OSCs with different HTLs were prepared. The power conversion efficiency and FF of the OSCs for the composite HTL can be greatly improved compared with the traditional HTL, which can reach up to 9.44% and 70.14%, respectively. The results of water contact angle and grazing incidence wide-angle X-ray scattering show that the hydrophobicity of the composite HTL is improved, which can not only improve the physical contact but also greatly affect the subsequent active layer formation, thus increasing the crystallinity of PTB7-Th:PC 71 BM. These results demonstrate that V 2 O 5 :PEDOT:PSS has good application prospects as a HTL to realize high-efficient OSCs. [ABSTRACT FROM AUTHOR]