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Surgical treatment is the most important and effective therapy for resectable esophageal cancer. Minimally invasive esophagectomy (MIE) can reduce surgical trauma. A neck incision can be performed for extraction of surgical specimen. This study was performed to investigate the safety and feasibility of neck incision to extract surgical specimen in thoracolaparoscopic esophagectomy for esophageal cancer.Thirty-four patients who experienced thoracolaparoscopic esophagectomy for esophageal cancer and a neck incision for extraction of surgical specimen were enrolled. The clinical, surgical and follow-up data were analyzed.The procedure was successful in all patients (100%), with a neck incision to extract the surgical specimen. The median surgical time was 309 min, and the median blood loss was 186 ml, with the mean length of hospital stay of 11.5 days. Pulmonary complications occurred in 8 patients (23.5%). Anastomotic leakage occurred in 5 patients (14.7%), with one patient being treated conservatively to recover and four (11.8%) who received interventional drainage. One patient with interventional drainage died of severe infection, resulting in a 30-day surgical mortality of 2.9% (n = 1). Gastrointestinal complications happened in 5 patients (14.7%), including ileus in three patients and anastomotic stenosis in two patients. Follow-up was performed at a median time of 20 months (interquartile range, 14-32 months), with no death during this period. No recurrence was found in the first 12 months after radical resection.The cervical incision to extract surgical specimen is safe and feasible with improved cosmetic effect in thoracolaparoscopic esophagectomy for esophageal cancer.

To explore the effectiveness and safety of laparoscopic transhiatal complete mesenteric resection (CME) surgery compared with those of the traditional laparoscopic transhiatal approach in the treatment of Siewert II/III adenocarcinoma of the esophagogastric junction (AEG).Ninety-nine patients with Siewert type II/III AEG were enrolled and divided into two groups: the laparoscopic CME transhiatal approach (CEM-TH, n = 61) group and traditional laparoscopic transhiatal (TH, n = 38) group. Intraoperative and postoperative clinical data of both groups were analyzed.The laparoscopic trasihiatal surgery was technically successful in all patients. The surgical time, intraoperative bleeding, and hospital stay were all significantly (P 0.05) reduced in the CME-TH group compared with those in the TH group. The levels of white blood cells on postoperative day (POD) 1 and 5, postoperative CRP on POD 3 and 5, and postoperative PCT were significantly (P 0.05) lower while lymph nodes were harvested significantly (P 0.05) more in the CME-TH group than in the TH group. Complications were not significantly (P 0.05) different between two groups. No death occurred within 90 days.The CME theory could be safely and effectively applied laparoscopically to treat patients with Siewert II/III AEG. Mesogastrium and lower mesoesophagus can be completely resected together with the tumor, lymph nodes, adipose tissue, and blood vessels as an "intact package," leading to better short-term outcomes.

The social defeat stress model is commonly used to study depression and anxiety disorder, which can significantly affect the structure and function of neurons in the hippocampus; however, the relevant mechanism in neuronal loss has not been clearly defined. In the present study, a social defeat stress model was established in mice to evaluate the impact of social defeat stress on the structure of neurons in the hippocampus using Western blotting, immunofluorescence, Nissl staining, Golgi staining and transmission electron microscopy. The results demonstrated that social defeat stress leads to disruption of homeostasis in the hippocampus and the integrity of mitochondria in hippocampal neurons was markedly affected by enhanced mitophagy and autophagy resulting in inhibition of development and growth. These findings provide new insights into the mechanisms of neuronal development and growth due to social defeat stress, which should help in the development of new strategies to combat the effects of depression and anxiety disorder.

Purpose To investigate the lymph node metastasis pattern and significance of dissection of the left gastric artery lymph nodes in radical en bloc esophagectomy for esophageal squamous carcinomas based on the lymphatic drainage pathway revealed by carbon nanoparticle labeling. Materials and methods Patients who underwent en bloc esophagectomy endoscopically were retrospectively enrolled. Carbon nanoparticles were injected in the submucosa of upper thoracic esophagus to label the relevant draining lymph nodes. The clinical data, lymph nodes dissected, surgical technique, and complications were analyzed. Results En bloc esophagectomy was successful in all 179 patients. Metastases to the left gastric artery lymph nodes were positive in 42 patients (23.5%) but negative in 137 (76.5%). The left gastric lymph nodes were labeled, whereas no celiac lymph nodes were labeled by carbon nanoparticles. A total of 4652 lymph nodes were resected, with 26 lymph nodes per patient. Seventy-three patients had lymph node metastasis (73/179). Seventeen patients had metastasis to the recurrent laryngeal nerve lymph nodes (9.5%). The metastasis rate of the lower thoracic esophageal cancer to the left gastric artery lymph nodes was 37.0%, significantly greater than that at the middle (15.4%) or upper (6.7%) thoracic segment. The lymph node metastasis rate was significantly (P < 0.05) increased with the length of the cancerous lesion, infiltration depth, and poor differentiation. Univariate analysis revealed that the metastasis rate to the left gastric artery lymph nodes was significantly (P < 0.05) associated with paraesophageal lymph node metastasis, para-cardial lymph metastasis, and TNM classification. Multivariate analysis indicated that cancer location (odds ratio 8.32, 95% confidence interval 2.12–32.24) was significantly (P < 0.05) associated with metastasis to the left gastric artery lymph nodes, with the cancer at the middle and lower thoracic segments significantly more than in the upper thoracic segment. Conclusion Certain patterns exist in lymph node metastasis of esophageal cancer, and in radical esophagectomy of esophageal cancers, dissection of the left gastric artery lymph nodes is necessary to prevent possible residual or metastasis of esophageal squamous carcinomas based on the lymphatic drainage pathway of esophageal carcinomas demonstrated by carbon nanoparticle labeling.

The multiscale structures in a Pd82Si18 binary bulk metallic glass before and after deformation were studied using electron microscopies, high-energy synchrotron X-ray diffraction, and small-angle scattering techniques. The experimental results revealed an enhancement of hierarchical structure heterogeneities on multiple length scales after deformation. Hierarchical multiple shear bands of high number density were observed after bending, introducing complex but periodically distributed residual strain. Pair distribution function analysis revealed that the connectivity of the short-range clusters on the medium-range scale determines the packing density difference between the tension side and the compression side in the sample after bending. In-situ synchrotron X-ray diffraction study also revealed a transformation of connection modes among short-range clusters under uniaxial tension and compression, which is consistent with those of triaxial tension/compression parts upon bending in Pd82Si18 glassy alloys. The nanoscale heterogeneities for metallic glasses after deformation observed by small-angle scattering and transmission electron microscopy may be attributed to the nanoscale amorphous phase separation and interacting multiple shear bands enhanced by plastic deformation. Our findings suggested that the enhancement of hierarchical heterogeneous structure on multiple length scales may explain the excellent plasticity of Pd-Si glassy alloys, deepening the understanding of structure-property relation during plastic deformation in metallic glasses.

Cervical cancer is the most common gynecologic malignant tumor, with a high incidence in 50-55-year-olds. This study aims to investigate the potential molecular mechanism of RRM2 for promoting the development of cervical cancer based on The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). RRM2 was found to be significant upregulated in cervical tissue (P

On the basis of the existing trace distance result, we present a simple and efficient method to tighten the upper bound of the guessing probability. The guessing probability of the final key k can be upper bounded by the guessing probability of another key k', if k' can be mapped from the final key k. Compared with the known methods, our result is more tightened by thousands of orders of magnitude. For example, given a 10^{-9}-secure key from the sifted key, the upper bound of the guessing probability obtained using our method is 2*10^(-3277). This value is smaller than the existing result 10^(-9) by more than 3000 orders of magnitude. Our result shows that from the perspective of guessing probability, the performance of the existing trace distance security is actually much better than what was assumed in the past., published version (with typing error corrected)

Systematic study was conducted on the microstructures and mechanical properties of nickel samples with two distinct types of heterostructures. The first is featured with coarse-grained lamellae embedded in a matrix consisting of a very high density of dislocation structures. The second is featured with coarse-grained zones embedded in the ultrafine-grained matrix. The second type of heterostructures exhibits better strength and ductility, although it has a smaller average grain size than the first type. The zone boundaries in the second type of heterostructures are less prone to cracking than those in the first type. Intersecting micro-shear-bands formed net-like patterns in the second type of heterostructures during tensile deformation. This is the first ever observation of structural micro-shear-bands in a heterostructured material. It supports the claim that heterostructure promotes the formation of dispersive shear bands. In contrast, a macroscopic shear band formed and caused early failure of the sample with the first type of heterostructures. Our results indicate that well-developed ultrafine/nano grained matrix in heterostructured materials are necessary for preventing crack formation and shear band localization. This should be considered as a key factor for optimizing the mechanical properties of heterostructured materials.

To reconstruct the ceRNA biological network of cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) and to select an appropriate mRNA as a biomarker that could be used for CESC early diagnosis and prognosis evaluation. We downloaded CESC data from the TCGA public database, and statistical analysis was conducted with the R software to find out differential expressed genes encoding for lncRNAs, miRNAs, and mRNAs. The differentially expressed mRNAs (DEmRNAs) screened in the ceRNA network were analyzed for survival to find the mRNAs with significantly linked to the survival prognosis. These mRNAs were searched in the Pathological Atlas to identify the final appropriate mRNAs. Differential expression analysis revealed 773 lncRNAs, 94 miRNAs, and 2466 mRNAs. Survival analysis of DEmRNAs in the ceRNA network indicated that ADGRF4, ANXA8L1, HCAR3, IRF6, and PDE2A (P<0.05) were negatively correlated with survival time. Verification of these six DEmRNAs in the Pathology Atlas indicated that PDE2A was a possible biomarker for CESC patients. PDE2A might be a biomarker for early diagnosis and prognosis evaluation of CESC patients, but due to the lack of available data, further studies may be needed for confirmation.

In the present research, the effects of friction stir welding (FSW) on the microstructure of 7075-T6 aluminum alloy (AA) thin sheet were investigated. For this purpose, three different welding rotational speeds of 600, 1000 and 1600 rpm at the constant traverse speed of 50 mm/min were studied. It was observed that FSW of an AA7075 thin sheet leads to an irrecoverable drastic reduction in the tensile properties. However, it was proven that for a thin sheet, at different rotational speeds, totally very different mechanisms of microstructural evolution were present within the stir zone (SZ). Also, it was observed that the mean grain size and subgrain density of the SZ have a nonlinear relation with rotational speed. Electron backscattered diffraction analysis indicated that continuous and discontinuous dynamic recrystallization is present within SZ simultaneously as the mechanisms of grain refinement, but with different effects. It was confirmed that heat input of the welding process in FSW of a thin sheet has a negligible effect on the microstructure, although the plastic strain is the determinant parameter. Also, the relationship between the microstructural observations and mechanical properties of friction stir-welded AA7075-T6 is discussed.

Objective This study was carried out to explore the potential involvement of miR‐125a‐5p in the oncogenic effects of EphA2, TAZ, and TEAD2 and the activity of the Hippo signaling pathway in gastric cancer progression. Methods In vitro transfection of miR‐125a‐5p mimics or inhibitors, qRT‐PCR, colony formation assays, and cell invasion assays were used to assess the effect of miR‐125a‐5p on the growth and invasion in gastric cancer (GC). Male nude mice bearing tumors derived from human GC cells were used for evaluating the effects of miR‐125a‐5p on tumor growth. Luciferase reporter assay, immunofluorescence, immunohistochemistry, qRT‐PCR, and immunoblotting were performed to explore the role of miR‐125a‐5p in the epithelial‐mesenchymal transition (EMT) and association among miR‐125a‐5p, EphA2, TAZ, and TEAD2 in GC cells. Results MiR‐125a‐5p enhanced GC cell viability and invasion in vitro, whereas inhibition of miR‐125a‐5p using a specific inhibitor and antagomir suppressed cancer cell invasion and tumor growth. Moreover, inhibition of miR‐125a‐5p reversed EMT in vitro. miR‐125a‐5p upregulated the expression of EphA2, TAZ, and TEAD2, promoted TAZ nuclear translocation, and induced changes in the activity of the Hippo pathway by enhancing the expression of TAZ target genes. Finally, miR‐125a‐5p was overexpressed in late‐stage GCs, and positive correlations were observed with its targets EphA2, TAZ, and TEAD2. Conclusion miR‐125a‐5p can promote GC growth and invasion by upregulating the expression of EphA2, TAZ, and TEAD2., miR‐125a‐5p may function as a powerful tumor promoter, activate the expression of its target genes EphA2, TAZ, and TEAD2, and promote cell growth, invasion, and epithelial‐mesenchymal transition in certain types of gastric cancer cells through activation of the Hippo pathway. miR‐125a‐5p may thus serve as a potential therapeutic target in the treatment of advanced gastric cancer cells.

Surgery is the only curative approach for resectable esophageal cancer. This retrospective study was to investigate the immediate effect and operative complications of conventional and modified thoracolaparoscopic esophagectomy with a cervical or abdominal incision to extract specimen for the treatment of patients with esophageal cancer. Eighty-one patients were enrolled, among which 55 patients underwent conventional McKeown thoracolaparoscopic esophagectomy (conventional MTE) and 26 patients underwent modified MTE with a cerivical incision (modified MTE). The clinical, surgical, and postoperative data were analyzed. No significant (P.05) difference was detected in the clinical data between two groups. The surgical procedure was successful in all patients (100%). The surgical time was significantly (P = .018) shorter in the conventional MTE group than in the modified MTE group (280 min vs 317 min). However, no significant (P.05) difference was found in blood loss (200 mL vs 180 mL), intensive care unit (ICU) stay (31.3 ± 11.3 vs 25.2 ± 6.4 hours), first flatus after surgery (2.9 ± 1.9 vs 3.3 ± 1.6 days), postoperative hospital stay (12.9 ± 5.6 vs 12.6 ± 3.3 days), total number of lymph nodes dissected (27.9 ± 4.1 vs 26.7 ± 5.7), types of carcinoma, and pathological classification. No significant (P.05) differences were detected in postoperative complications between the two groups. Assessment of postoperative pain using the visual analogue scale (VAS) score showed a significant (P.05) difference in the VAS score at day 2 (4.81 ± 1.70 vs 3.87 ± 1.14) and day 3 (5.10 ± 0.83 vs 4.61 ± 1.12) between the conventional and modified MTE groups. The modified McKeown thoracolaparoscopic esophagectomy with only one cervical incision is more minimally invasive, more cosmetic, and less painful than the conventional approach.

In this work the interactions of an edge dislocation with Cu precipitates of different diameters in α-Fe were investigated by molecular dynamics simulation. The influence of Fe atoms or outer Ni shell on the interactions was also studied. It is found that the dislocation stress field assists a structure transformation of the precipitates from BCC to FCC/HCP during the gliding of the dislocation. For the Cu precipitates with diameters less than 4 nm, most of the atoms return to BCC structure after the dislocation leaves away. The structure transformation of Cu-Fe precipitates is identical with pure Cu precipitates with diameters less than 4 nm. The outer Ni shells contribute the precipitate transformation to FCC/HCP structure and reduce the critical diameter of structure transformation. The critical resolved shear stress (CRSS) has been calculated for the precipitates and it is demonstrated that the FCC/HCP fraction of the precipitate contributes to the CRSS in this interaction.

A series of experimental studies are carried out to investigate the steady-state microstructures and mechanical properties of Cu, Ni, and Al obtained by equal-channel angular pressing (ECAP) at hom...

The parameters of shear band evolution with deformation were examined in the Vit105 bulk metallic glass. For this purpose, two halves of disks of the bulk metallic glass were joined together and processed by high-pressure torsion for various strains: from compression without rotation, to rotation for 5 revolutions. The discrepancy between the experimentally observed and predicted shear strains was detected. The actual strain is significantly smaller than the predicted one. The SEM examination of the internal surfaces of two joint halves of an HPT-processed disk allowed to study the formation and accumulation of shear bands under an increased imposed strain. The maximum density of the shear bands is observed at the edges of the HPT samples and in areas adjacent to the upper anvils. An increase in strain leads to an increase in the shear bands density. The observed minimum shear band spacing is equal to 0.5 μm after HPT processing for 5 revolutions. According to the structural changes recorded by XRD (an increase in the free volume content by about 1.3%) and formation of a high density of shear bands, HPT leads to a significant structural transformation of the amorphous structure of the BMG.

To investigate the effectiveness and clinical significance of thoracolaparoscopic esophagectomy with mesoesophagus excision.Patients who underwent en bloc mesoesophageal esophagectomy through thoracoscopy combined with laparoscopy were retrospectively enrolled. Carbon nanoparticles were used in some patients to label the esophageal drainage lymph nodes. The clinical data were analyzed.En bloc mesoesophageal esophagectomy was successfully performed in 135 patients (100%). The carbon nanoparticles were used in 10 patients, among which the left gastric arterial lymph nodes were labeled in all patients and excised together with the left gastric mesentery, mesoesophagus, esophageal cancer, lymph nodes, vessels, nerves, and adipose tissues as one intact package. The mean operation time was 182.5 ± 26.4 min, intraoperative blood loss 45.9 ± 17.6 ml, mean number of lymph nodes dissected 20.9 ± 8.12, extubation time of drainage tubes 7.5 ± 3.8 days, first oral feeding time 7.5 ± 1.8 days, and postoperative hospital stay 13 ± 5.11 days. Postoperatively, anastomotic leakage occurred in six patients (4.4%), anastomotic stenosis in eight (5.9%), hoarseness in seven (5.2%), and inflammation of the remnant stomach in four (3.0%), with a complication rate of 18.5%. Patients were followed up for 13-34 months (median 23). Eighteen patients presented with organ metastasis. No local recurrence or death during follow-up.Based on the membrane anatomy or mesoesophagus theory, thoracolaparoscopic en bloc mesoesophageal esophagectomy is safe, with decreased blood loss, and it is necessary to resect the left gastric artery lymph nodes together with the left gastric mesentery and its contents to completely remove the cancer.

Arecoline is a naturally occurring psychoactive alkaloid with partial agonism at nicotinic and muscarinic acetylcholine receptors. Arecoline consumption is widespread, making it the fourth (after alcohol, nicotine and caffeine) most used substance by humans. However, the mechanisms of acute and chronic action of arecoline in-vivo remain poorly understood. Animal models are a valuable tool for CNS disease modeling and drug screening. Complementing rodent studies, the zebrafish (Danio rerio) emerges as a promising novel model organism for neuroscience research. Here, we assessed the effects of acute and chronic arecoline on adult zebrafish behavior and physiology. Overall, acute and chronic arecoline treatments produced overt anxiolytic-like behavior (without affecting general locomotor activity and whole-body cortisol levels), with similar effects also caused by areca nut water extracts. Acute arecoline at 10 mg/L disrupted shoaling, increased social preference, elevated brain norepinephrine and serotonin levels and reduced serotonin turnover. Acute arecoline also upregulated early protooncogenes c-fos and c-jun in the brain, whereas chronic treatment with 1 mg/L elevated brain expression of microglia-specific biomarker genes egr2 and ym1 (thus, implicating microglial mechanisms in potential effects of long-term arecoline use). Finally, acute 2-h discontinuation of chronic arecoline treatment evoked withdrawal-like anxiogenic behavior in zebrafish. In general, these findings support high sensitivity of zebrafish screens to arecoline and related compounds, and reinforce the growing utility of zebrafish for probing molecular mechanisms of CNS drugs. Our study also suggests that novel anxiolytic drugs can eventually be developed based on arecoline-like molecules, whose integrative mechanisms of CNS action may involve monoaminergic and neuro-immune modulation.

The purpose of fingerprinting is to compare long messages with low communication complexity. Compared with its classical version, the quantum fingerprinting can realize exponential reduction in communication complexity. Recently, the multi-party quantum fingerprinting is studied on whether the messages from many parties are the same. However, sometimes it is not enough just to know whether these messages are the same, we usually need to know the relationship among them. We provide a general model of quantum fingerprinting network, defining the relationship function $f^R$ and giving the corresponding decision rules. In this work, we take the four-party quantum fingerprinting protocol as an example for detailed analysis. We also choose the optimal parameters to minimize communication complexity in the case of asymmetric channels. Furthermore, we compare the multi-party quantum fingerprinting with the protocol based on the two-party quantum fingerprinting and find that the multi-party protocol has obvious advantages, especially in terms of communication time. Finally, the method of encoding more than one bit on each coherent state is used to further improve the performance of the protocol., 12 pages, 4 figures

Previous researches have indicated that sleep plays a vital role in cognitive functions. Sleep deprivation (SD) causes learning and memory damage, which is associated with oxidative stress. This study was performed to investigate the neuroprotective effects of an extract of Abelmoschus manihot flower (EAM) against memory deficit induced by SD in mice. The SD model was evoked by multiple platform method for 5 days, successively. The learning and memory-improving effects of EAM were assessed by behavioral trials and the underlying mechanism was investigated by measuring the oxidative stress alteration. Our findings indicated that the SD-induced memory deficit and the EAM treatment improved the cognitive functions of mice in the object location recognition test and passive avoidance task. In addition, EAM effectively improved the activities of the antioxidant enzyme, decreased the content of malondialdehyde (MDA), and restored the protein expression of the brain-derived neurotrophic factor (BDNF), tyrosine kinase B (TrkB) and glutamate receptor 1 (GluR1) in brain tissues. In conclusion, EAM could improve the SD-evoked learning and memory impairments. The possible underlying mechanisms of EAM may be related to its antioxidant capacity and enhanced BDNF/TrkB/GluR1 levels in the hippocampal memory.

Tea waste biochar (TWBC) was prepared at 300℃, 500℃, and 700℃ under oxygen-limited atmosphere, and was characterized by elemental analysis, Brunauer-Emmett-Teller measurement, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. TWBC was then used to remove tetracycline from aqueous solution. The influences of solid-to-liquid ratio, pH, ionic types, and strength were investigated. The potential mechanism between tetracycline and TWBC was also explored. The results showed that the proper solid-to-liquid ratio was 4 g·L

Theranostics is a new trend integrating diagnostic and therapeutic functions in tumour research. Theranostic nanoparticles enabling both tumour imaging and drug delivery are a promising platform for image-guided cancer therapy. Photodynamic therapy (PDT) has great potential in synergy with traditional chemotherapy but faces great challenges due to hypoxia, poor targeting ability and the limited penetration depth of visible light. To solve these problems, we presented a novel nanosystem of FA/UCNPs–RB/HCPT/PFH@lipid (denoted as FURH-PFH-NPs), with a perfluorohexane (PFH) carrying rich oxygen core and a folic acid-modified lipid shell. The shell contains 10-hydroxycamptothecin (HCPT) and self-fluorescing photosensitizer compounds, namely, upconversion nanoparticles and rose bengal (UCNPs–RB). In this study, FURH-PFH-NPs aggregated in SKOV3 cells (in vitro) and the nude xenograft tumour region when combined with folic acid receptors. When triggered by low-intensity focused ultrasound (LIFU), FURH-PFH-NPs released PFH, UCNPs–RB and HCPT. The above procedure was monitored through multimodal imaging, which simultaneously guided the tumour therapy. UCNPs–RB and PFH promoted the PDT effect under LIFU. Through PDT and HCPT, we obtained better therapeutic effects and good biosafety against SKOV3 nude xenograft tumours. FURH-PFH-NPs combined with LIFU and laser irradiation might be a promising strategy for ovarian cancer.

The multiscale structures in a Pd82Si18 binary bulk metallic glass before and after bending were studied using electron microscopy, high-energy synchrotron X-ray diffraction, and small-angle X-ray scattering. The experimental results revealed the enhancement of hierarchical structure heterogeneities on multiple length scales after deformation. Hierarchical multiple shear bands of high number density can be observed after bending, introducing complex but periodically distributed residual strain. Pair distribution function analysis revealed that the connectivity of the short-range cluster on the medium-range scale determines the packing density difference between the tension side and the compression side in the sample after bending. The electron density fluctuations on the nanoscale observed in the deformed part of the sample are indicative of a nanoscale amorphous phase separation induced by plastic deformation. Our findings will deepen the understanding of the plastic deformation mechanism of metallic glasses and shed light on designing glassy alloys of excellent plasticity and toughness through hierarchical multiscale structure heterogeneities.

Superplastic Pb-Sn alloys were produced via tube high-pressure shearing (t-HPS), in a single step starting from elemental solid bulks. A Pb-40 wt% Sn alloy showed an exceptional superplastic elongation as high as ∼1870% at a strain rate of 1.0 × 10 −3 s −1 at room temperature, thereby elevating the optimum strain rate for maximum elongation under these conditions by more than one order of magnitude over conventional cast Pb-Sn alloys. This unprecedented room temperature superplasticity is attributed to the equiaxed grains having uniform sizes of the order of one micrometer, and in particular to the well-mixed domains of Pb and Sn in nearly equal proportions. This microstructure cannot be attained in cast eutectic or hypoeutectic alloys through conventional thermomechanical processing, but instead it is a direct outcome of t-HPS-generated compositional patterning at room temperature.

The grain size dependence of the strain rate sensitivity (SRS) of copper were systematically investigated via tensile deformation at strain rates of ~10−4 s−1 and ~103 s−1. In contrast to the general perception that SRS increases with decreasing grain size at low strain rates in FCC metals, the SRS increases monotonously with grain size under deformation at high strain-rates of ~103 s−1. Analytical formulation based on the Nemat-Nasser-Li (NNL) and Modified-Rusinek-Klepaczko (MRK) models was established to reveal the essential dependence of SRS on grain size, at the change of strain rate: that the opposite dependence of SRS on grain size at low vs high strain rates can be attributed to the transformation of the dominant rate-controlling deformation mechanism from thermal activation at low strain rates to viscous drag at high strain rates. It is demonstrated that the thermal activation component of SRS, m * , which is nearly strain rate independent, increases with reducing grain size; while the viscous drag component of SRS, m v s , which is enhanced significantly at high strain rates, decreases with reducing grain size. Microstructural observation based on local misorientation characterization and statistics confirms that the viscous-drag dominates at high strain-rate deformation, and becomes progressively influential as grain size increases. This unveils the essence of viscous drag in the opposite grain size dependence of SRS at low vs high strain rates.

The extensive deployment of surveillance cameras in public places, such as subway stations and shopping malls, necessitates automated visual-data processing approaches to match pedestrians across non-overlapping multiple cameras. However, due to the insufficient number of labeled training samples in real surveillance scene, it is difficult to train an effective deep neural network for cross-camera pedestrian recognition. Moreover, the cross-camera variation in viewpoint, illumination, and background makes the task even more challenging. To address these issues, in this paper we propose to transfer the parameters of a pre-trained network to our target network and then update the parameters adaptively using training samples from the target domain. More importantly, we develop new network structures that are specially tailored for cross-camera pedestrian recognition task, and implement a simple yet effective multi-level feature fusion method that yield more discriminative and robust features for pedestrian recognition. Specifically, rather than conventionally perform classification on the single-level feature of the last feature layer, we instead utilize multi-level feature by associating feature visualization with multi-level feature fusion. As another contribution, we have published our codes and extracted features to facilitate further research. Extensive experiments are conducted on WARD, PRID and MARS datasets, we show that the proposed method consistently outperforms state-of-the-arts.

The microstructure of commercial pure copper TP2 tube by three roll planetary mill processing was investigated. Due to work hardening and subsequent softing by dynamic recrystallization during milling process,the coarse grain structure of the copper transformed to fine grain structure. The grain refinement is achieved along the axial moving in general; in the reducing zone, the sample has a gradient structure along the radial direction; uniform equiaxed grain with size of ~2 μm could be obtained at the outlet. The initiation of dynamic recrystallization occurred in the three roll planetary mill the reduction engineering strain reach ~30%, where some equiaxed grains replaced the elongated grains because of recrystallization.

A novel type of sessile dislocation core structure and a 45° glissile dislocation are obtained in Au using high-resolution transmission electron microscopy. The formation mechanism of the sessile c...

Shear-coupled grain boundary (GB) motion (SCGBM) is an important and efficacious plasticity mechanism in the deformation of metals, especially nanocrystalline metals. In this work, molecular dynamic (MD) simulation has been performed to investigate the SCGBM of two [1 1 0] symmetric tilt GBs, Σ9[1 1 0](2 2 1) and Σ17[1 1 0](2 2 3), in α-iron, and the effects of temperature and strain rate on SCGBM have been studied. The coupling factor β which is defined as the ratio of the velocities of GB lateral translation and migration was calculated, and a geometric model of β depending on the misorientation angle was constructed in [1 1 0] symmetric tilt GBs of BCC metals. The model was branched into two modes (〈1 0 0〉 and 〈1 1 1〉) corresponding to the perfect dislocation Burgers vectors in BCC metals. The β values calculated in the 〈1 1 1〉 mode were in good agreement with the MD simulation results for both the GBs. Further, the atomistic mechanisms of the SCGBM processes were also investigated. A same structural unit transformation was observed for the two GBs, which confirmed that both Σ9[1 1 0](2 2 1) and Σ17[1 1 0](2 2 3) GBs moved in the 〈1 1 1〉 mode during the SCGBM process.