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In terms of first-principles method, the influences of Co, Cr, Fe, Ta, Mo and W atoms on the generalized stacking fault energy of Ni are investigated. The bridge between stacking fault energy and twinning is comprehensively constructed by various previous criterions. Our calculation results indicate that the addition of Mo has the maximum positive effect on the twinning of Ni, while Cr shows the minimum effect. The ranking sequence of twinning abilities can be drawn as: Ni-Mo > Ni-Fe ≈ Ni-Ta > Ni-W > Ni-Co > Ni > Ni-Cr. On the other hand, the addition of Fe or Ta significantly reduces the intrinsic stacking fault energy of Ni, which is beneficial to obtain the dislocation glide during deformations. Based on the analysis of charge density, the bonding characteristics near the fault plane are observed to reveal the electronic redistribution during the slipping. It is found that the intrinsic stacking fault configuration and double-layers twin configuration reconstitute stable bonds near the fault plane corresponding to two valley points of the GSFE curve, while these bonds will be disrupted under a series of displacements.

The precise information on phase constitutions in the Co-Ta system is of practical significance for exploiting γ′-strengthened Co-Ta-based superalloys. The unidentified crystal structure of χCo7Ta2 and the ambiguous description of phase relationship between χCo7Ta2 and γ′Co3Ta result in the uncertainty of phase constitutions in the Co-rich region of Co-Ta. In this work, we present a systematical study of crystallographic data of Co7Ta2 on the basis of first principles and an unbiased structure searching method. A layered-sandwich structure with C2/m monoclinic symmetry (Pearson symbol mC18) is identified for Co7Ta2. The thermodynamic, mechanical and phonon calculations further verify the stability of C2/m. The quasi-harmonic thermodynamics exhibit that Co3Ta is stable and Co7Ta2 should be metastable at ambient temperature. The entropy effect remarkably stabilizes Co7Ta2 but destabilizes Co3Ta phase. The Co7Ta2 would be the thermodynamically stable at T ≥ 1200 K. Further results of mechanical properties show that Co7Ta2 yields an unexpected intrinsic ductility. Through the electronic configurations, it demonstrates that the ductility is associated with the bonding alteration in the specific layered-sandwich structure of Co7Ta2 during deformation process.

White blood cells (WBCs) isolated from peripheral blood have been verified as important biomarkers for the diagnosis, treatment and prognosis of cancer. However, it’s still under challenge to acquire high-purity WBCs, even by taking advantage of current microfluidic technology. Considering the universality of clinical magnetic activated cell sorting (MACS) method, new developments on microfluidic chip in combination of magnetic cells separation technologies may provide a fascinating approach for high-purity WBCs sorting and widely clinical application. Here, we present a flyover style microfluidic chip which has been elaborately embedded with two-stage magnetic separation in continuous flow for WBCs sorting. Immunomagnetic micro/nano-particles (IMNPs) labeled WBC (WBC@IMNPs) were sequentially separated by a lateral magnetic force and a vertical magnetic force, and the final separation purity of WBCs reached up to 93 ± 1.67% at a flow rate of 20 μL min−1. Furthermore, the WBCs viability was up to 97.5 ± 1.8%. Consequently, this novel flyover style microfluidic-chip with magnetic separation technology has been successfully demonstrated as cut-in-edge method for high-purity WBCs sorting, and obviously it’s easy to extend for other types of cells sorting under great potential application in biomedical fields.

In many high temperature-resistant Ni-based superalloys, M23C6 carbides form during processing and remain as non-metallic inclusions during the materials use in application. M23C6 type inclusions are principal sites for potential fatigue crack initiation, thus the accurate quantification of their energy barriers for deformation is necessary for in-depth understanding of the overarching mechanical behavior of the material system. In this study, the generalized stacking fault energies (GSFE) are theoretically determined for chromium-rich types of M23C6 carbides (i.e., Cr23C6) in two prominent slip systems: {1 1 1}〈 1 1 2 ¯ 〉 and {1 1 1}〈 1 0 1 ¯ 〉. The results present GSFE curves with double saddle points in both slip systems. The double saddle points of the GSFE curves are explained via the electronic structure of atoms near the slip plane. At deformation quantified by half of a Burgers vector (i.e., 0.5 bp), a pentacyclic charge density distribution appears representing a local minimum energy configuration, which results in a valley of the GSFE curve. Furthermore, the effective coordination number (n) and the distortion index (Δd) of the coordination polyhedrons are employed to characterize the structural change. The analysis reveals that the values of the indexes n and Δd at a displacement value of 0.5 bp are close to the values of a perfect Cr23C6 crystal, while comparatively the distortion index is higher at the saddle points. These results provide new insights into the deformation pathways of M23C6 carbides.

Silicon carbide is widely used as ultra high-temperature ceramics, semiconductors, and pressure sensors with promising potentials for high-temperature, high-endurance, and radiation hardened applications. Daunting difficulties in experimental investigations of thermophysical properties hinder the better understanding of high-temperature material behaviors of silicon carbide. We present a comprehensive study of temperature-dependent mechanical and thermodynamic properties of SiC polytypes by first-principles methods. The obvious anisotropy of linear expansion and elasticity is found for 3C-SiC, while it is not distinct for other non-cubic SiC polytypes. Results show that the temperature dependences of mechanical properties exhibit the softening behavior, in which small linear reduction (∼4.4%) in Vickers hardness and shear modulus but large linear reduction (∼7.0%) in Young's modulus are detected. The heat-resistant properties of SiC polytypes are ranked as 3C-SiC

Keratinocyte growth factor (KGF)-2 has been highlighted to play a significant role in maintaining the endothelial barrier integrity in lung injury induced by ischemia-reperfusion (I/R). However, the underlying mechanism remains largely unknown. The aims of this study were to determine whether dexmedetomidine preconditioning (DexP) modulates pulmonary I/R-induced lung injury through the alteration in KGF-2 expression. In our I/R-modeled mice, DexP significantly inhibited pathological injury, inflammatory response, and inflammatory cell infiltration, while promoted endothelial barrier integrity and KGF-2 promoter activity in lung tissues. Bioinformatics prediction and ChIP-seq revealed that I/R significantly diminished the level of H3K4me3 modification in the KGF-2 promoter, which was significantly reversed by DexP. Moreover, DexP inhibited the expression of histone demethylase JMJD3, which in turn promoted the expression of KGF-2. In addition, overexpression of JMJD3 weakened the protective effect of DexP on lung injury in mice with I/R. Collectively, the present results demonstrated that DexP ameliorates endothelial barrier dysfunction via the JMJD3/KGF-2 axis.

It is essential to develop a simple synthetic strategy to improve the quality of multifunctional contrast agents for cancer diagnosis. Herein, we report a time-saving method for gadolinium (Gd) ions-mediated self-assembly of gold nanoclusters (GNCs) into monodisperse spherical nanoparticles (GNCNs) under mild conditions. The monodisperse, regular and colloidal stable GNCNs were formed via selectively inducing electrostatic interactions between negatively-charged carboxylic groups of gold nanoclusters and trivalent cations of gadolinium in aqueous solution. In this way, the Gd ions were chelated into GNCNs without the use of molecular gadolinium chelates. With the co-existence of GNCs and Gd ions, the formed GNCNs exhibit significant luminescence intensity enhancement for near-infrared fluorescence (NIRF) imaging, high X-ray attenuation for computed tomography (CT) imaging and reasonable r1 relaxivity for magnetic resonance (MR) imaging. The excellent biocompatibility of the GNCNs was proved both in vitro and in vivo. Meanwhile, the GNCNs also possess unique NIRF/CT/MR imaging ability in A549 tumor-bearing mice. In a nutshell, the simple and safe GNCNs hold great potential for tumor multi-modality clinical diagnosis., This work is supported by the National Key Basic Research Program (973 Project) (Project No. 2015CB931802), the National Natural Scientific Foundation of China (Grant Nos. 81401458, 81225010, 81028009, and 31170961), the 863 project of China (Project No. 2014AA020701), and the Shanghai Science and Technology Fund (Grant Nos. 14ZR1432400 and 13NM1401500).

Grain boundaries (GBs) have profound effects on the dislocation motion in materials so as to cause crack nucleation. However, the experimental observation on how the misorientation of twist GBs affects the crack nucleation is scarce. In this paper, we proposed a theoretical model to quantify the dislocation energy per unit length. With it, the critical resolved shear stress at GBs was calculated to assess the crack nucleation. It was found that crack nucleation is significantly influenced by the surface energy, grain boundary energy, system potential energy, boundary stress and misorientation. With the increase of the twist angle, high-angle GBs are more favorable for crack nucleation as general. Interestingly, some specific low-angle GBs possess comparable small critical resolved shear stress as the high-angle GBs and they are favorable for crack nucleation as well. Through the analysis of the resolved shear stress distribution of GBs, it is revealed that the crack nucleation mechanism of these specific low-angle GBs is similar to that of general high-angle GBs. It is inferred that the special low-angle GB systems could generate a crack under a relatively low resolved shear stress.

This study aimed to investigate the protective effect of GanodericacidA (GA) on myocardial ischemia-reperfusion (MIR) injury. The myocardial injury model in rats was established by ligating left anterior descending coronary artery. We measured cardiac hemodynamic, antioxidant enzyme activity, and various biochemical indexes of myocardial tissue, and evaluated myocardial infarction and damage. Further, the expression of JAK2/STAT3/NF-κB signaling pathway-related proteins in myocardial tissue was measured by western blot. The results showed that the myocardial infarction extention was obviously reduced upon GA treatment. Compared with the control group, ischemia-reperfusion rats showed significant increase in lactate dehydrogenase (LDH) and creatine Kinase (CK), which were significantly decreased in GA group. Besides, GA pretreatment effectively decreased the levels of inflammatory cytokines in serum. The phosphorylation of Janus Kinase 2 (JAK2), signal transducer and activator of transcription (STAT3)and Nuclear factor-κB (NF-κB) in reperfusion group were significantly higher than that in control group, which were reversed upon GA treatment. In conclusion, GA may reduce myocardial injury by regulating JAK2/STAT3/NF-κB pathway.

Background The development of next generation sequencing technology is rapidly changing the face of the genome annotation and analysis field. One of the primary uses for genome sequence data is to improve our understanding and prediction of phenotypes for microbes and microbial communities, but the technologies for predicting phenotypes must keep pace with the new sequences emerging. Scope of review This review presents an integrated view of the methods and technologies used in the inference of phenotypes for microbes and microbial communities based on genomic and metagenomic data. Given the breadth of this topic, we place special focus on the resources available within the SEED Project. We discuss the two steps involved in connecting genotype to phenotype: sequence annotation, and phenotype inference, and we highlight the challenges in each of these steps when dealing with both single genome and metagenome data. Major conclusions This integrated view of the genotype-to-phenotype problem highlights the importance of a controlled ontology in the annotation of genomic data, as this benefits subsequent phenotype inference and metagenome annotation. We also note the importance of expanding the set of reference genomes to improve the annotation of all sequence data, and we highlight metagenome assembly as a potential new source for complete genomes. Finally, we find that phenotype inference, particularly from metabolic models, generates predictions that can be validated and reconciled to improve annotations. General significance This review presents the first look at the challenges and opportunities associated with the inference of phenotype from genotype during the next generation sequencing revolution. This article is part of a Special Issue entitled: Systems Biology of Microorganisms.

A literature review of multiple clinical studies on mixing additives to improve pharmacologic limitation of local anesthetics during peripheral nerve blockade revealed inconsistency in success rates and various adverse effects. Animal research on dexmedetomidine as an adjuvant on the other hand has promising results, with evidence of minimum unwanted results. This randomized, double-blinded, contrastable observational study examined the efficacy of adding dexmedetomidine to a mixture of lidocaine plus ropivacaine during popliteal sciatic nerve blockade (PSNB).Sixty patients undergoing varicose saphenous vein resection using ultrasonography-guided PSNB along with femoral and obturator nerve blocks as surgical anesthesia were enrolled. All received standardized femoral and obturator nerve blocks, and the PSNB group was randomized to receive either 0.5 mL (50 µg) of dexmedetomidine (DL group) or 0.5 mL of saline (SL group) together with 2% lidocaine (9.5 mL) plus 0.75% ropovacaine (10 mL). Sensory onset and duration of lateral sural cutaneous nerve, sural nerve, superficial peroneal nerve, deep peroneal nerve, lateral plantar nerve, and medial plantar nerve were recorded. Motor onset and duration of tibial nerve and common peroneal nerve were also examined.Sensory onset of sural nerve, superficial peroneal nerve, lateral plantar nerve, and medial plantar nerve was significantly quicker in the DL group than in the SL group (P0.05). Sensory onset of lateral sural cutaneous nerve and deep peroneal nerve was not statistically different between the groups (P0.05). Motor onset of tibial nerve and common peroneal nerve was faster in the DL group than in in the SL group (P0.05). Duration of both sensory and motor blockade was significantly longer in the DL group than in the SL group (P0.05).Perineural dexmedetomidine added to lidocaine and ropivacaine enhanced efficacy of popliteal approach to sciatic nerve blockade with faster onset and longer duration.