Galerkin-based quasi-smooth manifold element(QSME)method for anisotropic heat conduction problems in composites with complex geometry

The accurate and efficient analysis of anisotropic heat conduction problems in complex composites is crucial for structural design and performance evaluation. Traditional numerical methods, such as the finite element method(FEM), often face a trade-off between calculation accuracy and efficiency. In this paper, we propose a quasi-smooth manifold element(QSME) method to address this challenge, and provide the accurate and efficient analysis of two-dimensional(2D) anisotropic heat conduction problems in composites with complex geometry. The QSME approach achieves high calculation precision by a high-order local approximation that ensures the first-order derivative continuity.The results demonstrate that the QSME method is robust and stable, offering both high accuracy and efficiency in the heat conduction analysis. With the same degrees of freedom(DOFs), the QSME method can achieve at least an order of magnitude higher calculation accuracy than the traditional FEM. Additionally, under the same level of calculation error, the QSME method requires 10 times fewer DOFs than the traditional FEM. The versatility of the proposed QSME method extends beyond anisotropic heat conduction problems in complex composites. The proposed QSME method can also be applied to other problems, including fluid flows, mechanical analyses, and other multi-field coupled problems, providing accurate and efficient numerical simulations.

Anti-plane pull-out of a rigid line inclusion from an elastic medium

The transient and static anti-plane problem of a rigid line inclusion pulled out from an elastic medium is studied.The singular integral equation method is used to solve the stress field.Under the static load,the stress intensity factor(SIF)at the inclusion tips increases with the medium length.The problem becomes equivalent to an inclusion in a medium with an infinite length when the length of the medium is 3.5times longer than that of the inclusion.However,under the transient load,the maximum value of the SIF occurs when the medium length is about two times the inclusion length.Besides,the relation between the pull-out force and the anti-plane displacement is given.The conclusions are useful in guiding the design of fiber reinforced composite materials.

Upregulation of GLE1 and LCP2 Genes in H5N1 Influenza Virus Infected Patients

Previous study showed that the Gle1 RNA export mediator-like (Gle1l) gene and the lymphocyte cytosolic protein 2 (Lcp2) gene were upregulated in response to influenza virus A/Puerto Rico/8/1934 (H1N1) in a mouse mode. To determine whether these two genes were upregulated in humans after influenza A virus infection, nasopharyngeal swabs were collected from eleven patients with flu-like symptoms for viral RNA extraction and PCR amplification. Sequencing analysis revealed that nucleoprotein (NP) gene fragments amplified from nasopharyngeal swabs of four patients shared the highest similarity with the NP gene from avian influenza A (H5N1) virus (A/ goose/Shantou/753/2002). Peripheral blood samples were then collected from four patients for quantitative analysis of GLE1 and LCP2 gene expression. Our results demonstrated that both GLE1 and LCP2 genes were upregulated in H5N1 influenza A virus infected patients, suggesting that upregulation of GLE1 and LCP2 genes may be important for the host defense against influenza A viruses.

Vibration analysis of piezoelectric sandwich nanobeam with flexoelectricity based on nonlocal strain gradient theory

A nonlocal strain gradient theory(NSGT) accounts for not only the nongradient nonlocal elastic stress but also the nonlocality of higher-order strain gradients,which makes it benefit from both hardening and softening effects in small-scale structures.In this study, based on the NSGT, an analytical model for the vibration behavior of a piezoelectric sandwich nanobeam is developed with consideration of flexoelectricity. The sandwich nanobeam consists of two piezoelectric sheets and a non-piezoelectric core. The governing equation of vibration of the sandwich beam is obtained by the Hamiltonian principle. The natural vibration frequency of the nanobeam is calculated for the simply supported(SS) boundary, the clamped-clamped(CC) boundary, the clamped-free(CF)boundary, and the clamped-simply supported(CS) boundary. The effects of geometric dimensions, length scale parameters, nonlocal parameters, piezoelectric constants, as well as the flexoelectric constants are discussed. The results demonstrate that both the flexoelectric and piezoelectric constants enhance the vibration frequency of the nanobeam.The nonlocal stress decreases the natural vibration frequency, while the strain gradient increases the natural vibration frequency. The natural vibration frequency based on the NSGT can be increased or decreased, depending on the value of the nonlocal parameter to length scale parameter ratio.

Laparoscopic abdomino-perineal resection for patients with anorectal malignant melanoma:a report of 4 cases

Anorectal malignant melanoma is a very rare but lethal disease. Patients with anorectal malignant melanoma commonly complain for changes in bowel habits and rectal bleeding. Therefore, anorectal malignant melanoma is often misdiagnosed as hemorrhoids, polyp or rectal cancer. Surgery is the mainstay of treatment for patients with anorectal malignant melanoma. However, whether abdominoperineal resection or wide local excision is the most appropriate surgical approach is still a controversial issue. Recently, with the great development of laparoscopic techniques, more and more operations can be performed by laparoscopic techniques. However, laparoscopic abdominoperineal resection for management of anorectal malignant melanoma has been rarely reported. In this study, we reported 4 patients with anorectal malignant melanoma underwent laparoscopic abdominoperineal resection. The outcomes of these patients were relatively good during a long time follow-up. Meanwhile, we reviewed the relevant studies with particular focus surgical treatment.

The potential of carcinoembryonic antigen,p53,Ki-67 and glutathion Stransferase-π as clinico-histopathological markers for colorectal cancer

Objective： Colorectal cancer is one of the major contributors to cancer death worldwide. Lack of reliable colorectal cancer markers has hampered the management of these cancer patients. Our main purpose was to study the correlation between histopathological variables of colorectal adenocarcinomas and identify histopathological markers that are of prognostic value in patients with colorectal cancer. Methods： In the present study, we examined the expression of carcinoembryonic antigen （CEA）, p53, Ki-67 and glutathion Stransferase （GST） -n by using immunohistochemical staining methods in 126 colorectal carcinoma patients and evaluated the lymph node metastasis status in these patients by histopathological examination. Results： The positive rates of CEA, p53, Ki-67 and GST-π expression in the colorectal cancer tissue specimens examined were 95.23%, 55.56%, 53.38% and 82.30%, respectively. Expression of p53 and Ki-67 was significantly correlated with the Dukes stages of the tumor, with higher levels of these proteins in Dukes＇ C and D tumors than those in Dukes＇ A and B tumors. Furthermore, the expression of p53, GST-π and Ki-67 correlated with prognosis of patients with colorectal cancer. Additionally, the expression of p53 in colorectal cancer was closely related to the expression of Ki-67 and the expression of GST-π was directly correlated with that of p53. Conclusion： The expression of CEA, p53, Ki-67 and GST-π was correlated with various clinical features of patients with colorectal cancer. The combined use of these histopathological markers appeared to be a promising tool in predicting the prognosis of patients with this type of cancer.

Mechanical properties of thermoelectric generators

To satisfy the requirements of practical applications,thermoelectric generators should be highly efficient and mechanically robust.Recently,progress in designing high-performance thermoelectric generators has been made.However,the mechanical properties of thermoelectric generators are still unsatisfactory.In this review,studies on the mechanical properties of thermoelectric generators are summarized.The me-chanical properties of bulk thermoelectric generators will be first discussed.In this section,the mechan-ical properties of thermoelectric materials and the strategies for improving their mechanical properties are emphasized.Since the device’s failure usually occurs at the interface between the thermoelectric ma-terials and electrode,the joint strength of electrodes and thermoelectric materials will be overviewed.After that,the mechanical properties of the inorganic thin-film thermoelectric devices will be discussed.Since the figure of merit for the flexibility of thermoelectric materials depends on the film thickness,elastic modulus,and yield strength,the synthesis methods of thin-film thermoelectric materials will be reviewed.Finally,this review will be concluded with a discussion on flexible organic thermoelectric de-vices and flexible devices using bulk legs.

锂沉积过程中固体电解质间相开裂与自愈合的原位观察

锂金属电池由于其超高的理论容量,被誉为是电池的"圣杯".然而,锂金属电池循环过程中树枝状或苔藓状锂的生长会使电池容量下降、电解液消耗、内部短路甚至起火爆炸.而直接追踪锂枝晶的生长仍然是一个巨大的挑战.本文报道了在CO_(2)气氛下利用环境电镜实时地观察了电化学诱导的锂沉积.研究发现单个锂沉积的形态强烈地受到固体电解质界面(SEI)开裂和自愈合的竞争过程的影响.当SEI膜的开裂速度超过自愈合时,锂晶须的定向生长占主导地位.相反地,当自愈大于裂纹时,圆形锂颗粒的各向同性生长将占主导地位.并且当SEI层是Li2O时,锂沉积的形貌只有球形,没有晶须的生成.因此,可以通过调节锂沉积速率和SEI成分来控制锂的形貌.本文还揭示了锂枝晶生长的一种新的"弱点"模式,这主要是由于在晶须截面上的Bardeen-Herring生长机制的作用.本研究对控制锂电池中锂枝晶的生长具有重要意义.

Biodegradation of pyrene by Phanerochaete chrysosporium and enzyme activities in soils:Effect of SOM,sterilization and aging

The impacts of soil organic matter （SOM）, aging and sterilization on the production of lignin peroxidase （LIP） and manganese peroxidase （MnP） by Phanerochaete chrysosporium during the biodegradation of pyrene in soils were investigated. The biodegradation of pyrene by P. chrysosporium decreased with increasing SOM content, whereas the maximum activities of LiP and MnP increased, which indicates that SOM outweighed pyrene in controlling enzyme production. Sterilization enhanced the degradation of pyrene due to the elimination of competition from indigenous microbes, whereas aging led to a reduction in the degradation of pyrene primarily through changes in its sorbed forms. Both sterilization and aging could reduce SOM content and alter its structure, which also influenced the bioavailability of pyrene and the enzyme activity. The sterilization and aging processes caused changes in the degradation of pyrene, and the enzyme activities were greater in soils with high SOM contents. MnP was related to the degradation of pyrene to a greater extent, whereas LiP was more related to the decomposition of SOM.

Treatment of severe acute pancreatitis through retroperitoneal laparoscopic drainage

A treatment method based on drainage via retroperitoneal laparoscopy was adopted for 15 severe acute pancreatitis(SAP)patients to investigate the feasibility of the method.Ten patients received only drainage via retroperitoneal laparoscopy,four patients received drainage via both retroperitoneal and preperitoneal laparoscopy,and one patient received drainage via conversion to laparotomy.Thirteen patients exhibited a good drainage effect and were successfully cured without any other surgical treatment.Two patients had encapsulated effusions or pancreatic pseudocysts after surgery,but were successfully cured after lavage and B ultrasound-guided percutaneous catheter drainage.SAP treatment via retroperitoneal laparoscopic drainage is an effective surgical method,resulting in minor injury.