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Tin mono‐selenide (SnSe) exhibits the world record of thermoelectric conversion efficiency ZT in the single crystal form, but the performance of polycrystalline SnSe is restricted by low electronic conductivity (σ) and high thermal conductivity (κ), compared to those of the single crystal. Here an effective strategy to achieve high σ and low κ simultaneously is reported on p‐type polycrystalline SnSe with isovalent Te ion substitution. The nonequilibrium Sn(Se1−xTex) solid solution bulks with x up to 0.4 are synthesized by the two‐step process composed of high‐temperature solid‐state reaction and rapid thermal quenching. The Te ion substitution in SnSe realizes high σ due to the 103‐times increase in hole carrier concentration and effectively reduced lattice κ less than one‐third at room temperature. The large‐size Te ion in Sn(Se1−xTex) forms weak SnTe bonds, leading to the high‐density formation of hole‐donating Sn vacancies and the reduced phonon frequency and enhanced phonon scattering. This result—doping of large‐size ions beyond the equilibrium limit—proposes a new idea for carrier doping and controlling thermal properties to enhance the ZT of polycrystalline SnSe. [ABSTRACT FROM AUTHOR]

Background: Sepsis is a common complication following pancreaticoduodenectomy (PD). The aim of this study was to evaluate the risk factors of sepsis based on serum inflammatory markers and clinical characteristics in patients who underwent PD. Methods: A total of 138 patients were enrolled in this study and all patients underwent curative PD. Logistic regression analysis was performed to identify risk factors for post‐operative sepsis. The patients' basic clinical features and inflammatory biomarkers including cytokines (IL‐1, IL‐2, IL‐6, IL‐8, IL‐10 and tumour necrosis factor‐α), procalcitonin, C‐reactive protein and peripheral neutrophil to lymphocyte ratio were analysed. Results: Of 138 patients, 31 developed sepsis during hospitalization. Univariate logistic regression analysis showed that body mass index, blood transfusion, operative time, American Society of Anesthesiologists score and diabetes were significant predictors of sepsis among all clinical characteristic variables. IL‐2, IL‐6, IL‐10, procalcitonin and C‐reactive protein were significant predictors among all inflammation biomarkers. By including different variables, three different regression models were obtained. The full model including all predictors mentioned above showed a C‐index of 0.831 and blood transfusion showed no statistically significance in this model. The reduced model 1 including blood transfusion showed a C‐index of 0.809. Another reduced model which included pre‐operative and intra‐operative variables showed a C‐index of 0.814 and this model could be used for early sepsis risk estimation. Conclusion: Pre‐operative IL‐6 was an independent risk factor for sepsis following PD. The three different predictive models could help early sepsis estimation for patients underwent PD. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare hard‐ and soft‐tissue changes after ridge preservation in periodontally compromised molar sockets with and without primary wound closure. Materials and Methods: Forty molars with severe periodontitis requiring extraction were included and allocated to two treatment modalities. After tooth extraction, the sockets were filled with deproteinized bovine bone mineral and covered with a bioabsorbable porcine collagen membrane. Primary wound closure was achieved in the control group, whereas the test group underwent minimally invasive open healing. The dimensions of the bone and soft tissue were recorded at baseline and 6 months. Results: Over 6 months, the control and test groups had similar mean ridge heights at the center of sockets of 8.59 ± 2.47 mm and 8.47 ± 2.51 mm, respectively. The total volume of the control group increased from 1070.17 to 1713.52 mm3 for a mean gain of 643.35 mm3, whereas that of the test group increased from 992.51 to 1514.05 mm3 for a mean gain of 521.54 mm3. Compared with the test group, the control group showed a statistically significant decrease in keratinized tissue width of 1.08 ± 1.63 mm. Conclusions: Bone dimensional changes following ridge preservation with and without primary wound closure were comparable. ARP without primary wound closure preserves more keratinized tissue than that with (Chinese Clinical Trial Registry: ChiCTR‐ONN‐16009433). [ABSTRACT FROM AUTHOR]

How speaking two languages affects executive functions has been a long‐standing debate and the mechanisms underlying the observed cognitive advantages of bilingualism remain unspecified. Here, using multivariate pattern classification methods, we decoded spatial patterns of neural signals associated with Flanker task performance in mono‐dialectal and bi‐dialectal speakers of Chinese. While univariate approach to even‐related potentials (ERPs) showed no between‐group difference, decoding accuracy of ERPs was reduced in bi‐dialectal as compared to mono‐dialectal speakers in both congruent‐neutral and incongruent‐neutral classifications. There was no effect of bidialectalism, however, on decoding accuracy of alpha‐band oscillations, an electrophysiological index implicated in inhibition. Behavioural data analysed using the Drift Diffusion Model (DDM) showed facilitating effects of bidialectalism on non‐decision times but no effect on drift rates. These findings demonstrate that using two dialects on a daily basis enhances general attentional deployment rather than affecting specific component of executive functions such as inhibitory control. Given that the two dialects of Chinese differed almost exclusively in phonology, the bidialectalism effect was most likely motivated by resolving phonological competition at lexical processing level. [ABSTRACT FROM AUTHOR]

Underwater Distance Measurement: Precise Underwater Distance Measurement by Dual Acoustic Frequency Combs (Ann. In article number 1900283, Hanzhong Wu, Jingsheng Zhai, and co-workers describe the successful generation of fully stabilized acoustic frequency combs. Long distances are able to be measured underwater using the dual-comb scheme, and the measurement uncertainty can achieve 50 µm. This work paves the way to future underwater applications using acoustic frequency combs. [Extracted from the article]

Underwater acoustics is of fundamental importance for marine science and technology. However, acoustic waves transmitted by state‐of‐the‐art underwater acoustic systems are not inherently phase locked, which hinders the development of underwater acoustic technology. For example, the precision of underwater distance measurement can only achieve centimeter level. As a versatile tool, optical frequency combs have enabled revolutionary progress in optical metrology and precision measurement. In parallel with optical frequency combs, here, the generation of fully stabilized, underwater acoustic frequency combs is reported, in which equidistant acoustic modes are produced via a hydroacoustic transducer. The precision of each individual acoustic mode is measured to be 10−9 at 1 s and 10−12 at 1000 s averaging times. Underwater distance measurements are carried out in an anechoic pool using a dual‐comb scheme. Comparison with reference values shows consistency within 50 µm (7 × 10−6 in relative). The relatively long‐duration experiments at 7 m distance yield an Allan deviation of 1.8 µm (2.6 × 10−7 in relative) at 1 s and further 480 nm (6.8 × 10−8 in relative) at 40 s averaging times. The approach to acoustic frequency comb generation offers a promising and powerful platform for future underwater distance measurement, positioning, and navigation. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNAs (miRNAs) are suspected to be a contributing factor in amyotrophic lateral sclerosis (ALS). Here, we assess the altered expression of miRNAs and the effects of miR‐124 in astrocytic differentiation in neural stem cells of ALS transgenic mice. Differentially expressed miRNA‐positive cells (including miR‐124, miR‐181a, miR‐22, miR‐26b, miR‐34a, miR‐146a, miR‐219, miR‐21, miR‐200a, and miR‐320) were detected by in situ hybridization and qRT‐PCR in the spinal cord and the brainstem. Our results demonstrated that miR‐124 was down‐regulated in the spinal cord and brainstem. In vitro, miR‐124 was down‐regulated in neural stem cells and up‐regulated in differentiated neural stem cells in G93A‐superoxide dismutase 1 (SOD1) mice compared with WT mice by qRT‐PCR. Meanwhile, Sox2 and Sox9 protein levels showed converse change with miR‐124 in vivo and vitro. After over‐expression or knockdown of miR‐124 in motor neuron‐like hybrid (NSC34) cells of mouse, Sox2 and Sox9 proteins were noticeably down‐regulated or up‐regulated, whereas Sox2 and Sox9 mRNAs remained virtually unchanged. Moreover, immunofluorescence results indicated that the number of double‐positive cells of Sox2/glial fibrillary acidic protein (GFAP) and Sox9/glial fibrillary acidic protein (GFAP) was higher in G93A‐SOD1 mice compared with WT mice. We also found that many Sox2‐ and Sox9‐positive cells were nestin positive in G93A‐SOD1 mice, but not in WT mice. Furthermore, differentiated neural stem cells from G93A‐SOD1 mice generated a greater proportion of astrocytes and lower proportion of neurons than those from WT mice. MiR‐124 may play an important role in astrocytic differentiation by targeting Sox2 and Sox9 in ALS transgenic mice. Cover Image for this issue: doi: 10.1111/jnc.14171. [ABSTRACT FROM AUTHOR]