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The observation of magnetoresistance (MR) varying with the rotation of magnetization in the plane perpendicular to the electric current is an important discovery in spintronics in recent years. The famous conventional anisotropic MR (AMR) says that the resistance of a polycrystalline magnetic material must depend on magnetization component along the current direction only, thus cannot account for this newly observed unusual AMR (UAMR). This UAMR leads to the notion of the spin-Hall MR (SMR) in the famous SMR theory. However, the SMR theory may only explain UAMR observed in heavy-metal/magnetic-insulator bilayers, not other types of bilayers. Here, we present a two-vector theory that can explain not only all existing experiments on the unusual angular dependence of longitudinal and transverse resistivity when the magnetization rotates in three mutually perpendicular planes, but also how three amplitudes of MR angular oscillation are related to each other. The theory is very general and its correctness depends only on the assumption that the magnetization and interfacial field are the only vectors affecting electron transport besides of other scalar variables such as the temperatures and impurities. Experiments that can test this theory against the SMR theory are also proposed.

There has been a plethora of studies on domain wall dynamics in magnetic nanostrips, mainly because of its versatile non-linear physics and potential applications in data storage devices. However, most of the studies focus on out-of-plane domain walls or in-plane head-to-head (tail-to-tail) domain walls. Here, we numerically study the field-driven dynamics of in-plane side-by-side domain walls in ferromagnetic strips, which can be stable in the presence of an in-plane easy-axis anisotropy transverse to the strip. The domain walls move in a rigid-body manner at low field, and show complex Walker breakdown behavior at high field. We observe a multi-step Walker breakdown through vortex nucleation in wide strips. In the presence of Dzyaloshinskii-Moriya interaction (DMI), the first Walker breakdown field first decreases then increases with interfacial DMI, while keeps increasing with bulk DMI. These findings complement the current understanding on domain wall dynamics., 13 pages, 9 figures

ABSTRACT: Multistage hydraulic fracturing in horizontal well is the key means to realize efficient development of shale reservoir. Traditional fracturing optimization mainly applies single factor analysis or orthogonal test based on numerical simulation, which is time consuming and is difficult to obtain the global optimal solution. In this paper, an optimization method of hydraulic fracturing design for horizontal shale gas well based on artificial neural network (ANN) and genetic algorithm (GA) is proposed. On the basis of collecting geology, engineering, and production data of fractured horizontal wells, the main production influencing factors are obtained with recursive feature elimination and cross validation method, then a data-driven production prediction model is constructed based on ANN, and the GA is used to search the global optimal combination of fracturing parameters. With the data set of 162 fractured horizontal wells from a shale gas field in Sichuan Basin, an ANN production prediction model is trained and tested. The calculation efficiency is high, and the determination coefficient exceeds 0.8. Furthermore, an optimal fracturing parameters combination strategy is proposed for a new completed well in this area. This method can provide some guidance for production evaluation and hydraulic fracturing design of horizontal shale gas wells. 1. INTRODUCTION Shale gas development mainly relies on horizontal well and staged fracturing, optimizing the fracturing strategy is critical to maximize well production and the ultimate recovery. The current fracturing optimization design mainly applies single factor analysis or orthogonal test methods to find the optimal horizontal well length, number of fractures, or fracture length, with the goal to maximize well production or net present value. However, limited by the search method and search interval, it is difficult to obtain the global optimal solution. What’s more, the optimization process is carried out with numerical simulator, involving complex and coupled fluid flow in matrix, natural fractures, artificial fractures and wellbore, so the calculation is time-consuming. Thanks to the increase of shale gas development efforts, data related to development and production are accumulating rapidly and continuously (Tan et al. 2017; Zhang et al. 2022). Therefore, extracting knowledge from the existing data, establishing a reliable and fast model to predict the well production, and then carrying out fracturing optimization with the combination of intelligent algorithm, is of practical interest for fracturing engineers.

Rectal cancer is a common malignant tumor of the digestive tract, and surgery is the main treatment strategy. Disorders of bowel, anorectal and urogenital function remain common problems after total mesorectal resection (TME), which seriously decreases the quality of life of patients. Surgical nerve damage is one of the main causes of the complications, while TME with pelvic autonomic nerve preservation is an effective way to reduce the occurrence of adverse outcomes. Intraoperative nerve monitoring (IONM) is a promising method to assist the surgeon to identify and protect the pelvic autonomic nerves. Nevertheless, the monitoring methods and technical standards vary, and the clinical use of IONM is still limited. This review aims to summarize the researches on IONM in rectal and pelvic surgery. The electrical nerve stimulation technique and different methods of IONM in rectal cancer surgery are introduced. Also, the authors discuss the limitations of current researches, including methodological disunity and lack of equipment, then prospect the future direction in this field.直肠癌是常见的消化道恶性肿瘤，其主要治疗策略是以手术为核心的综合治疗。排粪、排尿与性功能障碍是全直肠系膜切除术（TME）后常见的并发症，严重影响患者生活质量。保护盆腔自主神经的TME手术可以有效降低上述问题的发生率。术中神经监测（IONM）可以协助术者在术中有效地识别并保护盆腔自主神经，是一种颇有前景的方式，但目前技术标准尚不统一，临床应用尚不普及。本综述整理了国内外IONM在直肠癌手术以及盆腔相邻器官手术中的研究，介绍了神经电刺激结合海绵体、膀胱、尿道、直肠内压监测及肌电反应监测等IONM的技术方法。提出目前研究面临的方法学不统一、专用设施缺乏等问题，并对这一领域未来的发展方向进行展望。.

In the past, people summarized and invented a series of surgical procedures for the treatment of colorectal cancer after continuous thinking and exploration. Some of these surgical procedures, such as Miles, Dixon, and Hartmann procedures, are considered to be classic and still in use today. In general, the surgical development has gone through roughly four stages: palliative surgery, radical surgery, extended radical surgery, and tumor functional surgery. As far as the surgical procedure of colorectal surgery is concerned, it mainly includes five elements: surgical approach, intestinal segment resection, degree of lymph node dissection, digestive tract reconstruction, and specimen removal. Only by fully understanding the five elements of surgical procedures and seeking for variables from them can innovation be achieved and benefit patients. This article will discuss the evolution of colorectal surgery according to development of medicine and surgery. "Taking history as a mirror, we can know the rise and fall." Only by correctly understanding history can we objectively understand the nature of things and the laws of their development. This is true for humans, and it is true for medicine.在过去的临床实践中，人们通过不断的思考与探索，总结、发明了一系列关于结直肠癌治疗的手术术式，其中一些术式，如Miles术、Dixon术、Hartmann术一直沿用至今，堪称经典。结直肠外科术式的发展经历了大致四个阶段：减状手术、根治性手术、扩大根治性手术和肿瘤功能外科阶段。主要包括了手术入路、肠段切除范围、淋巴结清扫程度、消化道重建以及标本取出这五个要素。只有充分了解术式构成的五大要素，从中寻求变量，才能取得创新，从而造福患者。该文将结合医学及外科的发展过程，浅谈结直肠外科术式的演变历程。“以史为鉴，可以知兴替”。只有正确认识历史，才能客观地了解事物的本质及其发展规律。.

With the development of lightweight technology, advanced high strength steel (AHSS) had been widely used in automotive and construction industry. However, twist defect restricts the application of thin-walled components with asymmetric section. In this work, AHSS MS1500 was taken to investigate the complex non-linear elastoplastic behaviors and twist defect in roll forming process. Finite element analysis (FEA) model was established by COPRA software and the material model considered Young’s modulus variation with plastic deformation and material anisotropy was selected. With the developed model, the mechanism of twist defect was discussed and the effect of forming strategy on twist defect was analyzed. For asymmetric hat channel steel, the asymmetric residual longitudinal stress is the principal reason for twist defect. Loading patterns have a significant effect on twist defect and the developed UDT-type (USTB-Durable-type) method can control twist defect effectively. This study has provided theoretical and technical support on large-scale application of AHSS.

In order to obtain the pure shear deformation characteristics along the circumferential direction of tubes, a circumferential shear test for thin-walled tubes is proposed in this paper. The experimental device consists of a tubular sample and two cylindrical mandrels with shear plates. The torque along the circumferential direction was applied to the tubular sample by the two shear plates to make the pre-set shearing zone of the sample under a circumferential pure shear stress state. The two cylindrical mandrels support the inner wall of the tube to avoid buckling so that the pure shear stress state can be maintained during the whole deformation process. A 5052 aluminum alloy tube with an outer diameter of 50 mm and a wall thickness of 1.2 mm was used in the test. It is shown through simulation and experiment that shear deformation is concentrated in the pre-set shearing zone. This test can be used to obtain the circumferential pure shear stress-strain relationship.

In the past 30 years, minimally invasive surgery has been greatly improved with the development of the energy platform, instrument platform, and imaging platform. Taking colorectal cancer surgery as an example, the five elements of surgical procedure have developed to a certain extent. The surgical approach has undergone a process from large to small. The range of resection ranges from simple bowel resection to radical resection/extended radical resection, and then to surgery that focuses on preserving organ function. With the recognition of the direction of normal lymphatic drainage and the characteristics of tumor lymphatic metastasis, lymph node dissection has been gradually standardized. The reconstruction of the digestive tract has changed from manual sutures to full endoscopic anastomosis, and then to the concept of functional anastomosis. The removal of the specimen has improved from large incision through the abdominal wall, to small laparoscopic incision, and then to the natural cavity. The evolution of these procedures depends on the advancement of technology platforms and equipment, and the recognition of new concepts. The development of minimally invasive platform must be in the direction of ensuring the implementation of the most optimized surgical approach. The platform is more secure, integrated, multifunctional, and intelligent. In the future, minimally invasive procedures must be aimed at maximizing the benefits of patients. The procedures are more scientific, functional, comfortable and diverse. Surgical innovation has promoted the development of the platform. The platform and the surgical procedure promote each other's development.近30年来，随着能量平台、器械平台、显像平台三大手术平台的发展，微创外科有了突飞猛进的提升。以结直肠癌手术为例，手术方式的五要素都有着不同程度的发展：手术入路经历了"从大到小"的过程；切除范围从单纯肠段切除到根治术或扩大根治术，再到注重保留器官功能的手术；随着对正常淋巴引流方向和肿瘤淋巴转移特点的认知，淋巴结清扫愈趋规范；消化道重建从手工缝合到全腔镜下吻合，再到功能性吻合概念的提出；标本取出从经腹壁大切口，到腹腔镜小切口，再到经自然腔道。这些术式的演变都依赖于技术平台与设备的进步及对新理念的认知。未来微创平台一定是为保障最优化术式顺利实施为方向，平台更为安全化、一体化、多功能化、智能化；未来微创术式一定是以追求患者最大获益为目标，术式更为科学化、功能化、舒适化、多样化；而术式的革新又推动了平台的发展，二者相辅相成，互相促进。.

In this chapter, we review recent developments of two usages of topology in magnetism. One is to classify spin structures with different topological numbers (topology in real space). The other usage is to distinguish normal magnetic materials from those magnetic materials supporting topologically protected unidirectional surface spin waves inside spin wave band gaps (topology in reciprocal space).

Neuroendocrine neoplasms (NENs) are relatively rare heterogeneous tumors that originate from peptidergic neurons and neuroendocrine cells and have been referred to as "carcinoids" in the past. Although this type of tumor had been previously considered to be indolent tumor with a low degree of malignancy, with the development of medicine and clinical study, researchers found that NENs had the potential to metastasize. They can occur in any part of the body where neuroendocrine cells are distributed and gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) are the most common type of NENs.Due to the improvement of techniques such as endoscopy and imaging, the incidence of rectal neuroendocrine tumors(R-NENs) and the number of related clinical researches have both increased significantly in recent years. Although researches in Chinese and foreign medical centers are mostly retrospective studies of small samples and the efficacies of different treatment methods are still under debating and lack of sufficient medical evidence to support, the diagnosis and treatment of this disease is gradually becoming standardized according to the proposal of corresponding guidelines. The recent advances in the epidemiology, diagnosis and treatment of rectal neuroendocrine neoplasms are reviewed in this paper.神经内分泌肿瘤是一种起源于肽能神经元和神经内分泌细胞的相对罕见的异质性肿瘤，既往被认为是一种恶性程度不高的惰性肿瘤。但随着医学研究的深入，研究者发现，神经内分泌肿瘤具有转移的潜能。它可以发生在全身任何有神经内分泌细胞存在的部位，其中胃肠道胰腺神经内分泌肿瘤是最常见的神经内分泌肿瘤类型。由于内镜和影像学等检查技术的发展，近年来，直肠神经内分泌肿瘤的发病率明显上升，与之相关的临床研究逐渐增多。尽管国内外各中心的研究多为小样本回顾性分析，不同治疗方式的疗效尚存在争议且缺乏充分的循证医学证据加以支持，但随着国内外相应指南的提出，直肠神经内分泌肿瘤的诊治也正逐步走向规范化。文中结合有关直肠神经内分泌肿瘤近年来的流行病学特征、诊断和治疗的研究进展进行阐述。.

High tibial osteotomy (HTO) is an effective treatment for knee osteoarthritis. With the application of bi-planer open wedge osteotomy high tibial osteotomy and new angular stable locking plates, HTO has become more accuracy, minimally invasive and standard, achieved satisfactory long-term treatment outcome. The indications of HTO are expanding. We need to comprehensively consider whether the patient has varus deformity, the location and severity of the deformity, the stage of osteoarthritis, age and the demand of activity, as well as individual factors such as weight, gender, bone condition and joint activity, and strive to give the best individualized treatment to osteoarthritis patients in different stages.胫骨高位截骨术（HTO）是治疗膝关节骨关节炎的有效术式。胫骨内侧双平面开放截骨术和锁定钢板固定技术的应用，使HTO实现了精准化、微创化和标准化，取得了令人满意的长期疗效，HTO的适应证也在不断拓展。临床工作中需综合考虑患者是否存在内翻畸形及畸形的部位和严重程度，骨关节炎所处阶段，年龄和活跃程度需求，以及体重、性别、骨质情况、关节活动度等个体因素，为处于不同阶段的骨关节炎患者制定最佳的个体化治疗方案。.

Gastric cancer (GC) is one of the most common malignant tumors in the world, which is seriously harmful to people's health. The increasing number of studies have shown that long non-coding RNA (lncRNA) is related to the occurrence of gastric cancer. In this study, we aimed at investigating the role of lnc FTX in the occurrence of gastric cancer.The expression of FTX in gastric cancer patients and gastric cancer cell lines was detected by RT-qPCR. Univariate Kaplan-Meier method was used to analyze the relationship between FTX expression level, clinicopathological parameters and overall survival rate (OS). After transferring si-FTX and overexpression FTX plasmids into MGC-803 and SGC-7901, the expression of miR-215-3p was detected by RT-qPCR, and the changes of cell proliferation and cell cycle were detected by CCK-8 and flow cytometry. In addition, luciferase activity was used to detect whether miR-215-3p combined with FTX and SIVA1. Finally, Western blot (WB) was used to detect the change of SIVA1 protein expression by miR-215 mimic.We found that the expression of FTX in tumor tissues of 71 GC patients was higher than that in paracancerous tissues, and the prognosis of patients with high FTX was poor. The expression of FTX in gastric cancer cells was higher than that in normal human gastric epithelial cells (GES-1). Transferring overexpression plasmid of FTX into gastric cancer cells (MGC-803 and SGC-7901) promoted cell proliferation and the ratio of cells in G0-G1 phase was decreased. Transferring si-FTX to MGC-803 and SGC-7901 led to opposite results. There was a negative correlation between the expression of mi215-3p and FTX in MGC-803 and SGC-7901 gastric cancer cells, and luciferase results showed that mi215-3p could directly bind to FTX and regulate cell growth and cell cycle changes. In addition, luciferase results showed that mi215-3p could bind directly to SIVA1. What's more, RT-qPCR and WB results showed that mi215 mimic could promote the expression of MGC-803, SGC-7901 SIVA1mRNA and protein.According to these results, this study revealed that the previously neglected FTX-miR2153p-SIVA1 regulatory axis for the regulation of gastric cancer progression, which may be a potential target for the treatment of gastric cancer.

探讨高龄直肠癌患者腹会阴联合切除术(APR)后会阴切口并发症发生的相关危险因素。

报道上海第l例确诊新型冠状病毒（2019-nCoV）感染患儿的诊治经过。患儿 男，7岁，因"发热3 h伴咳嗽"以及父亲被确诊2019-nCoV感染的肺炎收入复旦大学附属儿科医院负压病房。经过对症治疗后治愈。儿童2019-nCoV感染临床表现相对成人较轻，家庭内传播是儿童感染重要的途径。本例患儿虽然症状轻，但恢复期连续2次2019-nCoV核酸检测阳性，提示需要观察轻症儿童病例在恢复期无症状排毒的传染性。.

We report the experimental observation of second-order corner states in a two-dimensional breathing honeycomb topolectrical circuit with sixfold rotational symmetry [Formula: see text] through voltage measurements. The topological corner states originate from the nontrivial bulk topology, which can be characterized by the topological invariant associated with the rotation eigenspectrum. We confirm two types of corner states, both originate from the [Formula: see text] symmetry, while one of them is specially pinned to zero admittance because of the emerging chiral symmetry protection. We then examine the robustness of zero modes in the presence of next-nearest-neighbor hopping terms that destroy chiral symmetry but still preserve [Formula: see text] symmetry. Our work provides a paradigm in circuit systems to study the exotic topological physics.

Purpose/Objective(s) The responses of human head and neck cancer (HNSCC) cells to photon (XRT) and proton (PRT) radiotherapy can be enhanced by a poly-(ADP-ribose) polymerase (PARP)-1 and PARP-2 inhibitor (PARPi) with undefined underlying mechanisms. We hypothesize that elucidating these mechanisms will facilitate a personalized selection of PARPi in combination with XRT or PRT. Herein, the effects of PARPi on XRT and PRT induced cell death, cell cycle distribution, and related protein expression in HNSCC cells were defined. Materials/Methods Human papillomavirus (HPV)-negative HN5, SqCC/Y1, and HPV-positive UPCI-SCC-154, UM-SCC-47 cell lines were tested. Cells were exposed to a 4 Gy PRT or XRT with or without PARPi (1 µM, 1 hour [h] before radiation). Cell cycle distribution, cell necrosis and apoptosis (staining with Annexin-VFITC) were determined using terminal deoxy-nucleotidyltransferase dUTP nickend labeling assay and were analyzed by flow cytometry. Cell mitotic catastrophe (co-staining for cytoplasm with γ- tubulin for nucleus with Dapi), and senescence (assessed using SA-β-gal) were examined. Protein expressions were determined by western blot or by flow cytometry. Results PARPi significantly increased XRT and PRT induced cellular senescence at 6 days in the two HPV+ cell lines, with higher percentages of senescence in PRT than XRT cells (P all Conclusion In conclusion, PARPi induced higher levels of mitotic catastrophe in combination with PRT versus XRT, promoted XRT and PRT induced senescence, while it led to a trend of increased cell necrosis after PRT and XRT. These upregulating effects of PARPi were cell line dependent. Cell line based delayed DNA damage repair and increase in radiation-induced cell cycle arrest at G2/M phase may have served as parts of the underlying mechanisms. Further studies on personalized therapy of XRT or PRT in combination with PARPi to improve the efficacy of radiotherapy are warranted.

It has been shown that a single-domain magnetic nanoparticle can be effectively switched by a linear down-chirp microwave field pulse (DCMWP) in zero temperature limit. However, finite temperature is ubiquitous in practice. Here, we study the effect of finite temperature on the DCMWP-induced magnetization reversal based on the stochastic Landau-Lifshitz-Gilbert equation. It is found that any one of the three controlling parameters of a DCMWP, i.e. the amplitude, chirp rate, or initial frequency, decreases with increasing temperature while the other two are fixed. The maximal temperature at which the reversal can happen increases with enlarging the system size. These phenomena are related to the facts that the energy barrier induced by anisotropy increases with the system volume, and the effective magnetization decreases with temperature. We also provide a set of optimal parameters for practical realization of our proposal. These findings may provide a way to realize low-cost and fast magnetization reversal with a wide operating temperature.

To better understand the origin of water in the Badain Jaran Desert, China, water samples were collected from lakes, a spring and local unconfined aquifer for analyses of radiocarbon (14C), tritium (3H), stable hydrogen and oxygen isotope ratios (δ2H – δ18O), and d-excess values ( = δ2H – 8δ18O). A series of evaporation experiments were also conducted in the desert to examine how the isotopic signature of water may change during evaporation and infiltration under local environmental conditions. The results show that the lakes in the southeastern sand dune area are fed by groundwater discharging into the lakes and that local groundwater, on the other hand, is derived primarily from modern meteoric precipitation in the region. Although dissolved inorganic carbon (DIC) in groundwater yielded very old radiocarbon ages, the presence of detectable amounts of tritium in groundwater samples, together with their δ2H, δ18O and d-excess characteristics, strongly suggests that the old radiocarbon ages of DIC do not represent the residence time of water in the aquifer but are the result of addition of old DIC derived from dissolution of ancient carbonates in the aquifer. The data do not support the hypothesis that the water in the Badain Jaran Desert was sourced in remote mountains on the northern Tibetan Plateau. This study also finds no support for the hypothesis that present-day water resources in the desert were recharged by the precipitation that fell in the past during the early Holocene when the climate was much wetter than today. Instead, this study shows that both groundwater and lake water originated from meteoric precipitation in the region including mountainous areas adjacent to the desert under the modern climatic condition.

We analyse a parallel (identical) machine scheduling problem with job delivery to a single customer. For this problem, each job needs to be processed on $m$ parallel machines non-pre-emptively and then transported to a customer by one vehicle with a limited physical capacity. The optimization goal is to minimize the makespan, the time at which all the jobs are processed and delivered and the vehicle returns to the machine. We present an approximation algorithm with a tight worst-case performance ratio of $7/3-1/m$ for the general case, $m\geq 3$.

High-efficiency flexible solar modules are fabricated with thin-film GaAs solar cells to satisfy the demand for power generation systems of unmanned aerial vehicles (UAVs) and stratospheric airships. The polyimide substrate inverted metamorphic triple junction (IMM 3J) GaAs thin-film solar cells are interconnected using the electrically conductive films by low temperature hot press welding technology, and the solidity of welding and efficiency loss ratio of the cells reach the level of rigid GaAs triple junction solar cells used in space now. Two different size solar cells are integrated and encapsulated separately using the thermo-sensitive adhesive supporting films to achieve a good laminating performance. The 0.2 m2 flexible module consisting of unfilled corner cells has the specific power over 750 W/kg (AM0, 1353 W/m2), and the 0.5 m2 flexible module consisting of rectangle cells has higher specific power over 800 W/kg benefit from a higher cell-to-module ratio (CTM). The two modules have an areal density of less than 500 g/m2. Several near space reliability tests have been done to verify that the flexible solar modules could meet the special environment application need.