Large-gap quantum spin Hall insulators in tin films

The search of large-gap quantum spin Hall (QSH) insulators and effective approaches to tune QSH states is important for both fundamental and practical interests. Based on first-principles calculations we find two-dimensional tin films are QSH insulators with sizable bulk gaps of 0.3 eV, sufficiently large for practical applications at room temperature. These QSH states can be effectively tuned by chemical functionalization and by external strain. The mechanism for the QSH effect in this system is band inversion at the \Gamma point, similar to the case of HgTe quantum well. With surface doping of magnetic elements, the quantum anomalous Hall effect could also be realized

Bis[(1H-1,2,3-benzotriazol-1-yl)methyl 2,2-dimethyl­propano­ato-κN 3]dichlorido­copper(II)

In the title compound, [CuCl2(C12H15N3O2)2], the CuII ion is located on an inversion center and is four-coordinated in a distorted square-planar geometry by two chloride anions and two N atoms from two (1H-1,2,3-benzotriazol-1-yl)methyl 2,2-dimethyl­propano­ate ligands. The Cl—Cu—N angles of 90.55 (9) and 89.45 (9)° are close to ideal values. In the crystal, weak π–π stacking inter­actions are observed between inversion-related benzene rings [centroid–centroid distance = 4.0028 (6) Å]

Evidence for line nodes in the energy gap of the overdoped Ba(Fe1−x_{1-x}Cox_{x})2_{2}As2_{2} from low-temperature specific heat measurements

Low-temperature specific heat (SH) is measured on Ba(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$ single crystals in a wide doping region under different magnetic fields. For the overdoped sample, we find the clear evidence for the presence of $T^2$ term in the data, which is absent both for the underdoped and optimal doped samples, suggesting the presence of line nodes in the energy gap of the overdoped samples. Moreover, the field induced electron specific heat coefficient $\Delta\gamma(H)$ increases more quickly with the field for the overdoped sample than the underdoped and optimal doped ones, giving another support to our arguments. Our results suggest that the superconducting gap(s) in the present system may have different structures strongly depending on the doping regions.Comment: 5 pages, 4 figure

Age as a risk factor for acute mountain sickness upon rapid ascent to 3,700 m among young adult Chinese men.

BackgroundThe aim of this study was to explore the relationship between age and acute mountain sickness (AMS) when subjects are exposed suddenly to high altitude.MethodsA total of 856 young adult men were recruited. Before and after acute altitude exposure, the Athens Insomnia Scale score (AISS) was used to evaluate the subjective sleep quality of subjects. AMS was assessed using the Lake Louise scoring system. Heart rate (HR) and arterial oxygen saturation (SaO2) were measured.ResultsResults showed that, at 500 m, AISS and insomnia prevalence were higher in older individuals. After acute exposure to altitude, the HR, AISS, and insomnia prevalence increased sharply, and the increase in older individuals was more marked. The opposite trend was observed for SaO2. At 3,700 m, the prevalence of AMS increased with age, as did severe AMS, and AMS symptoms (except gastrointestinal symptoms). Multivariate logistic regression analysis showed that age was a risk factor for AMS (adjusted odds ratio [OR] 1.07, 95% confidence interval [CI] 1.01-1.13, P<0.05), as well as AISS (adjusted OR 1.39, 95% CI 1.28-1.51, P<0.001).ConclusionThe present study is the first to demonstrate that older age is an independent risk factor for AMS upon rapid ascent to high altitude among young adult Chinese men, and pre-existing poor subjective sleep quality may be a contributor to increased AMS prevalence in older subjects

Fourier Coefficients of Asynchronous Collective Motions in Heavy-ion Collisions

We present a novel scenario in heavy-ion collisions where different modes of collective motions evolve asynchronously in the created nuclear medium. Such physics mechanisms could each dominate at a distinct evolution stage, or coexist simultaneously without coordinating with each other. If we employ a separate single-harmonic Fourier expansion to describe how each asynchronous collective motion affects particle emission, the particle azimuthal distribution should be the product of all these expansions. Consequently, cross terms between collectivity modes appear, and their contributions to experimental observables could be significant. In particular, we argue that the chiral magnetic effect (CME) and elliptic flow can develop asynchronously, with their convolution affecting the observable that is sensitive to the shear-induced CME. We will use the event-by-event anomalous-viscous fluid dynamics model to illustrate the effects of this scenario. Besides giving new insights into searches for the CME, we also propose a feasible experimental test based on conventional flow harmonics

Effects of chronic liver disease on the outcomes of simultaneous resection of colorectal cancer with synchronous liver metastases: a propensity score matching study

IntroductionGiven the rising prevalence of chronic liver disease (CLD), it is increasingly important to understand its impact on surgical outcomes. Our aim was to evaluate the impact of CLD on short-term outcomes in patients with colorectal cancer and synchronous liver metastases undergoing simultaneous surgery.MethodsWe retrospectively reviewed patients with colorectal cancer and liver metastases who underwent simultaneous resection between January 2013 and June 2022. Patients were divided into the CLD and non-CLD groups. Data regarding short-term surgical outcomes were compared between the two groups.ResultsA total of 187 patients were included. After propensity score matching, there were 42 patients in each group, and the basic characteristics of the two groups were similar. Patients with CLD had a significantly greater incidence of postoperative complications (47.6% vs. 26.2%; P = 0.042). The operation times of the CLD and non-CLD groups were similar (297 vs. 307.5 min, P = 0.537), and the blood loss was comparable between the two groups (250 vs. 155 ml, P = 0.066). No significant differences were observed between the two groups in pneumonia (P > 0.999), urinary infection rate (P > 0.999), ileus rate (P = 0.474), wound infection rates (P > 0.999), abdominal infection rate (P = 0.533), anastomotic leakage rate (P > 0.999), digestive hemorrhage rate (P > 0.999), bile leakage rate (P > 0.999), hepatic hemorrhage rate (P > 0.999), reoperation rate (P > 0.999), intensive care rate (P > 0.999), or severe liver failure (P > 0.999). There were no deaths in the two groups. CLD significantly prolonged the length of hospital stay (P = 0.011).DiscussionCLD is an important factor affecting postoperative complications in patients with colorectal cancer liver metastases undergoing simultaneous surgery. Considering the large number of patients with CLD in China, more attention and medical care should be provided to patients with CLD who require simultaneous resection of colorectal cancer with synchronous liver metastases

States, trends, and future of aquaponics research

As an environmentally-friendly aquaculture and planting system, aquaponics has attracted attention in various fields, such as fisheries, agriculture, and ecology. The existing review qualitatively described the development and challenges of aquaponics but lacked data support. This study selected 513 related documents (2000-2019) in the Web of Science database (WOS) to mine and quantitatively analyze its text data. The keyword co-occurrence network shows that the current aquaponics research mainly focuses on the system components, wastewater treatment, nutrient management, and system production. Research areas reflect obvious regional characteristics. China, the United States and Europe are dedicated to the application of new technologies, the optimization of system production, and the exploration of multiple roles. At present, the aquaponics development is facing many pressures from management and market. Future research requires more in-depth research in the system construction, nutrient management, and microbial community structure to provide a theoretical basis. Moreover, the identity construction within the conceptual framework of green infrastructure is a research direction worth exploring to solve low social recognition for aquaponics