Generalized transfer matrix theory on electronic transport through graphene waveguide

In the effective mass approximation, electronic property in graphene can be characterized by the relativistic Dirac equation. Within such a continuum model we investigate the electronic transport through graphene waveguides formed by connecting multiple segments of armchair-edged graphene nanoribbons of different widths. By using appropriate wavefunction connection conditions at the junction interfaces, we generalize the conventional transfer matrix approach to formulate the linear conductance of the graphene waveguide in terms of the structure parameters and the incident electron energy. In comparison with the tight-binding calculation, we find that the generalized transfer matrix method works well in calculating the conductance spectrum of a graphene waveguide even with a complicated structure and relatively large size. The calculated conductance spectrum indicates that the graphene waveguide exhibits a well-defined insulating band around the Dirac point, even though all the constituent ribbon segments are gapless. We attribute the occurrence of the insulating band to the antiresonance effect which is intimately associated with the edge states localized at the shoulder regions of the junctions. Furthermore, such an insulating band can be sensitively shifted by a gate voltage, which suggests a device application of the graphene waveguide as an electric nanoswitch.Comment: 11 pages, 5 figure

GaitRef: Gait Recognition with Refined Sequential Skeletons

Identifying humans with their walking sequences, known as gait recognition, is a useful biometric understanding task as it can be observed from a long distance and does not require cooperation from the subject. Two common modalities used for representing the walking sequence of a person are silhouettes and joint skeletons. Silhouette sequences, which record the boundary of the walking person in each frame, may suffer from the variant appearances from carried-on objects and clothes of the person. Framewise joint detections are noisy and introduce some jitters that are not consistent with sequential detections. In this paper, we combine the silhouettes and skeletons and refine the framewise joint predictions for gait recognition. With temporal information from the silhouette sequences. We show that the refined skeletons can improve gait recognition performance without extra annotations. We compare our methods on four public datasets, CASIA-B, OUMVLP, Gait3D and GREW, and show state-of-the-art performance.Comment: IJCB 2023. Code is available at https://github.com/haidongz-usc/GaitRe

ShARc: Shape and Appearance Recognition for Person Identification In-the-wild

Identifying individuals in unconstrained video settings is a valuable yet challenging task in biometric analysis due to variations in appearances, environments, degradations, and occlusions. In this paper, we present ShARc, a multimodal approach for video-based person identification in uncontrolled environments that emphasizes 3-D body shape, pose, and appearance. We introduce two encoders: a Pose and Shape Encoder (PSE) and an Aggregated Appearance Encoder (AAE). PSE encodes the body shape via binarized silhouettes, skeleton motions, and 3-D body shape, while AAE provides two levels of temporal appearance feature aggregation: attention-based feature aggregation and averaging aggregation. For attention-based feature aggregation, we employ spatial and temporal attention to focus on key areas for person distinction. For averaging aggregation, we introduce a novel flattening layer after averaging to extract more distinguishable information and reduce overfitting of attention. We utilize centroid feature averaging for gallery registration. We demonstrate significant improvements over existing state-of-the-art methods on public datasets, including CCVID, MEVID, and BRIAR.Comment: WACV 202

Mechanism of Action of Policy-Related Factors on Chinese Employees’ Early Retirement Behavior

Nowadays, aging is a global challenge to most of countries. Retirement age, as an important factor to aging problem, has become a hot issue in the academic world. Especially in China, how to adjust retirement age is a complicated but interesting problem. This study, based on the CHARLS (China Health and Retirement Longitudinal Study) data of 2011, explored the influencing factors for Chinese employees’ early retirement behavior, and focused on the influencing mechanism on policy-related factors working age and pension. In Part One, binary logit regression method was used to research the influencing factors for the early retirement of Chinese staff and workers, as well as the influence relation between working age and pension, concluding that a longer working age led to a higher pension level but a lower probability of early retirement, and finding that employees’ re-employment after early retirement under pressure from life caused by the lower average pension level in China was a major reason for the negative correlation between pension and early retirement. In Part Two, an “Moderated Mediator” model was built based on an analysis of the preliminary study and an interview with the employees in different types of units, result showing that pension had some intermediary effects between working age and early retirement, and meanwhile the effects were under the positive adjustment of work in public institution. Finally, some policy suggestions were put forward in this study for the adjustment of retirement policy. Keywords: early retirement, working age, pension, public institution, moderated mediator

Effect of renin-angiotensin system inhibitors on acute kidney injury among patients undergoing cardiac surgery: A review and meta-analysis

10.1053/j.semtcvs.2020.11.024SEMINARS IN THORACIC AND CARDIOVASCULAR SURGERY3341014-102

Reduced Risk of Colorectal Cancer With Metformin Therapy in Patients With Type 2 Diabetes

Objective: Both in vitro and in vivo studies indicate that metformin inhibits cancer cell growth and reduces cancer risk. Recent epidemiological studies suggest that metformin therapy may reduce the risks of cancer and overall cancer mortality among patients with type 2 diabetes. However, data on its effect on colorectal cancer are limited and inconsistent. We therefore pooled data currently available to examine the association between metformin therapy and colorectal cancer among patients with type 2 diabetes. Research Design and Methods: The PubMed and SciVerse Scopus databases were searched to identify studies that examined the effect of metformin therapy on colorectal cancer among patients with type 2 diabetes. Summary effect estimates were derived using a random-effects meta-analysis model. Results: The analysis included five studies comprising 108,161 patients with type 2 diabetes. Metformin treatment was associated with a significantly lower risk of colorectal neoplasm (relative risk [RR] 0.63 [95% CI 0.50–0.79]; P < 0.001). After exclusion of one study that investigated colorectal adenoma, the remaining four studies comprised 107,961 diabetic patients and 589 incident colorectal cancer cases during follow-up. Metformin treatment was associated with a significantly lower risk of colorectal cancer (0.63 [0.47–0.84]; P = 0.002). There was no evidence for the presence of significant heterogeneity between the five studies (Q = 4.86, P = 0.30; I2 = 18%). Conclusions: From observational studies, metformin therapy appears to be associated with a significantly lower risk of colorectal cancer in patients with type 2 diabetes. Further investigation is warranted

Effect of dietary soy isoflavones on bone loss in ovariectomized rats

Purpose: To determine the effect of dietary soy isoflavone supplementation on bone loss in ovariectomized (OVX) rats.Methods: Forty-eight rats were assigned randomly to groups of OVX rats receiving soy isoflavones (20, 30, or 40 mg/kg of body weight daily), untreated OVX rats, or untreated intact rats. After 8 weeks, bone mineral density (BMD), mineral (Ca, P, Mn, Mg, and Zn) concentrations, and the expression of osteoblast-related genes were measured in femur tissue samples.Results: Eight weeks after OVX, there was a significant decrease in body weight, serum levels of osteocalcin, alkaline phosphatase, and oestradiol, BMD and mineral elements, as well as the expressions of Ctnnb1, Runx2, and Sp7 (all p &lt; 0.05). These decreases were accompanied by reduced maximum load capacity of lumbar vertebrae. Daily supplementation with soy isoflavones dosedependently ameliorated these effects (all p &lt; 0.05). Western blotting revealed that these effects were likely due to the reversal of the OVX-induced decrease in Notch1 proteins in bone and muscle.Conclusion: Soy isoflavone treatment represents a potential therapy for preventing postmenopausal bone loss by stimulating the Notch signalling.Keywords: Mineral elements, Alkaline phosphatase, Isoflavones, Bone loss, Notch pathwa

Necrotizing Sarcoid Granulomatosis with Hemoptysis: A Case Report and Literature Review

We present a case of 39-year-old male with the symptoms of fever, cough, chest pain and bloody phlegm, whose chest CT showed multiple subpleural nodules and inflammatory infiltration. Video-Assisted Thoracic Surgery ( VATS ) for right subplural nodule was performed and confirmed the diagnosis of necrotizing sarcoid granulomatosis. Prednisolone was administered and the symptoms were under control untill the occurrence of intermittent hemoptysis after 10 months. Chest CT and bronchoscope revealed the right lower lobe nodule with intraluminal necrotic tissue in the right lower lobe posterior basal segment respectively. Fatal hemoptysis happened during endobronchial biopsy by flexible bronchoscope forcep. Based on this case, we reviewed the relevant literature and discussed the clinical features, pathological changes and prognosis of the disease