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Uniaxial and isothermal compression tests of kaolinite were carried out using molecular dynamics simulations. Five different temperatures (300, 400, 500, 600 and 700 K) and pressures ranging from 0.0001 to 50 GPa were selected to study the temperature and pressure effects on the mechanical properties of kaolinite. As kaolinite may undergo a phase transition at ~1572 K, a highest temperature of 700 K was chosen to avoid such structural change. The Young's modulus, strength and elastic constants of kaolinite under various temperatures were calculated, and the relative change of the elastic constant C33 with temperature was found to be almost 12 times greater than the relative change of the interlayer constant C11. The microstructures under various compressive strains were tracked and they exhibited various failure modes in three directions. The temperature and pressure effects on the mechanical properties of three crystal directions were analysed. The results showed that the Young's modulus of the z-direction is the most affected by temperature; however, the influence of temperature on the strengths of the three crystal directions was the same. In addition, the structure of the z-direction was the most sensitive to temperature under the same hydrostatic pressure due to the weak interactions between layers.

Soil flushing using prefabricated vertical drains (PVDs) is an innovative subsurface remediation technology for contaminated fine-grained soils. An analytical solution is presented to investigate the performance of a PVD-enhanced system arranged in a rectangular pattern for soil remediation. The analytical solution is derived based on a simplified equivalent model in which PVDs are substituted by drain walls. The results of the analytical solution are shown to be roughly consistent with those obtained from the finite-element method. Using the proposed solution, the remediation efficiency for a rectangular layout is demonstrated to be higher than that for a parallel layout. Furthermore, the effects of distance between injection and extraction PVD, injection rate, distribution coefficient, and dispersivity are investigated. Results indicate that a square pattern is the optimal layout of PVDs compared to other rectangular patterns. Increasing the injection rate of individual PVDs is an effective way to improve the remediation efficiency. The increase of distribution coefficient of contaminant leads to a significant increase in the remediation time, and the increase of longitudinal and transverse dispersivity results in a more uniform spatial distribution of contaminant concentration during the flushing process.

Early comprehensive assessment and early intervention of vascular disease, and the life-time maintenance of vascular health are the key to effectively preventing death and disability in end-stage of heart, brain, kidney and peripheral vascular events. Based on this concept, it is necessary to establish a professional clinical discipline of "vascular medicine" which is based on the systemic vascular bed, with measures on prevention, treatment, rehabilitation and intellectualized and digital vascular health management throughout the life cycle for different vascular lesions and different degree of vascular injury. The aim of the establishment of Beijing Vascular Health Stratification (BVHS) is to give a comprehensive and dynamic assessment of vascular health based on the concept of vascular medicine, to conduct individualized analysis of the results, to classify the degree of injury on vascular structure and function, to carry out individualized intervention, and eventually achieve targeted precise prevention and management, establish newly intellectualized and digital vascular health management medical model in China, for effectively reducing the incidence of cardiovascular events.对血管早期病变的综合评估和早期干预，血管健康的全生命周期维护是有效预防致死致残心、脑、肾和周围血管事件的关键，基于这一理念，需要建立“血管医学”专业临床学科，以全身血管床为核心，对不同部位血管病变和不同病变程度的人群，进行预防、治疗以及系统康复，并进行全生命周期的血管健康智慧化和数字化管理。北京血管健康分级法（BVHS）提出的目的就是根据血管医学的理念，对血管健康给予综合动态评估，并将其结果进行个体化分析，将血管结构及功能病变程度综合分级，以对各危险等级人群进行个体化精准干预，实现针对性地预防和管理，建立全新的智慧化数字心脏和血管健康医学模式，有效降低心脑血管事件的发生。.

The major objective of this review was to compare the diagnostic accuracy of ultrasound in confirming tracheal intubation to the standard methods of confirmation in the intensive care unit (ICU).This systematic review and meta-analysis of observational studies was conducted from inception to July 2022. We included studies that compared the diagnostic accuracy of ultrasound-detected tracheal intubation to that of the gold standard diagnostic technique performed in adult patients who underwent tracheal intubation as part of any procedure. We searched the following electronic databases for published studies: PubMed, EMBASE, Cochrane Central, and Web of Science. Risk of bias was assessed using a standard procedure based on the Quality Assessment of Diagnostic Accuracy Studies-2 criteria. The results were analyzed using the RevMan or Meta-Disc software to determine the adequacy and conclusiveness of the available evidence.Five studies that included 344 patients met the inclusion criteria. Pooled sensitivity was 0.96 (95% confidence interval (CI) (0.92-0.98) and 1.00 (95% CI: 0.97-1.00), respectively. Furthermore, the diagnostic odds ratio of ultrasonography was 311.25 (95% CI: 63.77-1,519.22), which was confirmed by a summary receiver operating characteristic curve with an area under the curve of 0.98.Ultrasonography has high sensitivity and specificity, is a valuable adjunct for confirming tracheal intubation in the ICU and should be performed when capnography is unavailable or unreliable.

对于合并多种晕厥危险因素、出现过晕厥事件，且植入植入式心脏转复除颤器（ICD）二级预防的患者，再发晕厥时的诊疗和鉴别诊断颇具挑战性。本文报道因既往反复室性心动过速合并长QT综合征植入ICD的患者再发晕厥，最终溯因为肺血栓栓塞症的1例病例，并复习相关文献，以探讨合并多种晕厥危险因素时的优化晕厥诊疗模式。.

The interplay between various symmetries and electronic bands topology is one of the core issues for topological quantum materials. Spontaneous magnetism, which leads to the breaking of time-reversal symmetry, has been proven to be a powerful approach to trigger various exotic topological phases. In this Letter, utilizing the combination of angle-resolved photoemission spectroscopy, magneto-optical Kerr effect microscopy, and first-principles calculations, we present the direct evidence on the realization of the long-sought spontaneous ferromagnetism induced topological transition in soft ferromagnetic EuB_{6}. Explicitly, we reveal the topological transition is from Z_{2}=1 topological insulator in paramagnetic state to χ=1 magnetic topological semimetal in low temperature ferromagnetic state. Our results demonstrate that the simple band structure near the Fermi level and rich topological phases make EuB_{6} an ideal platform to study the topological phase physics.

Acute respiratory distress syndrome (ARDS) is a critical disease commonly found in many clinical cases, with a mortality rate of approximately 50%. Early diagnosis and intervention are important for improving ARDS prognosis. In this study, the applications of lung ultrasound in ARDS diagnosis and assessment are reviewed to clarify its key clinical values and application prospects.According to the standard diagnosis of ARDS based on the Berlin definition, CXR or CT examination should be conducted. However, both the blurred images of the former, as well as the inconvenience and high risks of the latter, impose restrictions on their application in critically ill patients.Lung ultrasound was shown to improve safety, effectiveness, lacked radiation, can be performed bedside, and offers dynamic functionality.It may be a suitable approach to replace or complement traditional imaging examinations with lung ultrasound.

Fuzzy C-means (FCM) clustering algorithm is a widely used method in data mining. However, there is a big limitation that the predefined number of clustering must be given. So it is very important to find an optimal number of clusters. Therefore, a new validity function of FCM clustering algorithm is proposed to verify the validity of the clustering results. This function is defined based on the intra-class compactness and inter-class separation from the fuzzy membership matrix, the data similarity between classes and the geometric structure of the data set, whose minimum value represents the optimal clustering partition result. The proposed clustering validity function and seven traditional clustering validity functions are experimentally verified on four artificial data sets and six UCI data sets. The simulation results show that the proposed validity function can obtain the optimal clustering number of the data set more accurately, and can still find the more accurate clustering number under the condition of changing the fuzzy weighted index, which has strong adaptability and robustness.

Thymus, an important central immune organ in pigs, is the site of T lymphocyte development and maturation and an important target organ for infection and replication of various pathogens. Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) infection results in severe thymic atrophy in piglets. This study aimed to explore the effects of HP-PRRSV on the thymic structure of piglets to elucidate the pathogenesis of thymic atrophy induced by HP-PRRSV. In this study, histopathological techniques and immunofluorescence double staining techniques were used to analyze thymic tissues infected by HP-PRRSV to explore the structural changes of thymus caused by the viral infection and its target cell types. An antibody of cluster of differentiation (CD) 3 (CD3), CD20, CD80, or calgranulin + calprotectin was applied to identify T cells, B cells, dendritic cells (DCs), and macrophages, respectively. The results indicated that a variety of cell components in the thymic tissue were diffusely damaged after viral infection. In the infected thymic tissue, CD80- or calgranulin + calprotectin- -labeled cells supported the HP-PRRSV infection, whereas CD3-labeled T cells and CD20- -labeled B cells did not support the viral infection. The results showed that HP-PRRSV caused the reduction of visible cell components in the thymic tissue, and the virus attacked CD80- and calgranulin + calprotectin-positive cells (such as DCs and macrophages) in the thymic tissue, which played an important role in the pathogenesis of thymus atrophy. These results lay the foundation for elucidating the immunosuppression of piglets after infection with HP-PRRSV.

患者男，69岁。6个月前因突发失语及肢体活动障碍，于外院诊断为“左心房黏液瘤”并手术切除，3个月前突发言语不清及肢体活动障碍，症状逐渐加重，对症治疗无明显改善后来山东大学齐鲁医院（青岛）就诊，影像学显示左侧额叶及顶叶占位，手术切除。病理检查：广泛出血及血管继发性变的背景中见小灶疏松黏液样基质，基质内见稀疏梭形、星芒状细胞，免疫组织化学Calretinin染色阳性，最终诊断为心房黏液瘤颅内播散伴广泛出血。.

下颌第一磨牙的根管系统形态复杂多样，其牙根数目及形态均可能发生较大变异。本文报道的1例多根管患者双侧下颌第一磨牙均存在远中中央根管，且右下第一磨牙近中根同时存在低分叉的Ⅴ型根管。患牙治疗过程中，结合锥形束CT影像学、牙科显微镜、超声治疗仪等辅助手段，完成了多根管的根管治疗及患牙冠部修复，术后18个月复查效果良好。.

Topological superconductors have long been predicted to host Majorana zero modes which obey non-Abelian statistics and have potential for realizing non-decoherence topological quantum computation. However, material realization of topological superconductors is still a challenge in condensed matter physics. Utilizing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations, we predict and then unveil the coexistence of topological Dirac semimetal and topological insulator states in the vicinity of Fermi energy (EF) in the titanium-based oxypnictide superconductor BaTi2Sb2O. Further spin-resolved measurements confirm its spin-helical surface states around EF, which are topologically protected and give an opportunity for realization of Majorana zero modes and Majorana flat bands in one material. Hosting dual topological states, the intrinsic superconductor BaTi2Sb2O is expected to be a promising platform for further investigation of topological superconductivity.

Enteral nutrition (EN) is the first-choice nutritional support, as it is more in line with normal physiological processes. During EN, the major goals to achieve include accurate confirmation of the feeding tube position, monitoring the gastric residual volume, assessing gastrointestinal motility, and monitoring the nutritional status of patients. With rapid development in technology, point-of-care ultrasound (POCUS) has become a more convenient and effective technical tool for monitoring critically ill patients receiving EN. In this review, we have summarized and discussed the value of POCUS in the implementation, monitoring, and evaluation of EN therapy to provide a reference for nutritional support of critically ill patients in critical care settings.This is a narrative review. A literature search for Scopus-indexed articles was performed randomly using PubMed and MEDLINE databases as the primary sources. No specific term was used for the search.POCUS can be used for positioning of nasogastric and nasointestinal tubes, evaluation of gastric residuals and gastrointestinal motility as well as monitoring of nutritional status.POCUS is a real-time, highly repeatable, radiation-free, and non-invasive visual inspection technique, with high application value in assessing the nutritional status of patients receiving EN and guiding the development of further nutritional treatment plans. It is an important diagnostic and monitoring tool that can be used by the clinicians in the ICU.

With the progress of medical imaging technology and the accumulation of experience, dual-energy CT has moved from simple scientific research to clinical application. In the imaging of abdominal tumors, dual-energy CT has obvious advantages over conventional CT in improving the diagnostic performance, reflecting the pathological characteristics of malignant tumors and evaluating the therapeutic effect. This paper briefly describes the classification of dual-energy CT, the current research status of this technology in abdominal malignant tumors, and puts forward the challenges and application traps faced by dual-energy CT technology, in order to promote the clinical generalization and application of this technology.随着医学影像检查技术的进步与经验的积累，双能量CT已从单纯科学研究走向临床应用。在腹部肿瘤成像中，双能量CT在提高诊断性能、反映恶性肿瘤病理特征和评估治疗效果等方面较常规CT具有明显优势。本文简述了双能量CT的分类、目前该技术在腹部恶性肿瘤的研究现状，提出了双能量CT技术面临的挑战与应用陷阱，以期推进该技术的临床普及应用。.

Clustering validity function is an index used to judge the accuracy of clustering results. At present, most studies on clustering validity are based on single clustering validity function. Research shows that no clustering validity function can handle any data and always perform better than other indexes. Therefore, a hybrid weighted combination evaluation method based on fuzzy C-means (FCM) clustering validity functions was proposed. The weighting method combines expert weighting with information entropy weighting to improve the subjective factor influence of expert weighting and the shortcoming of information entropy weighting in the value judgment of each clustering validity function. Four clustering validity function combination methods of linear, exponential, logarithm and proportion was studied. Finally, the proposed fuzzy clustering validity evaluation method is verified by experiments on artificial data sets and UCI data sets. The experimental results show that the proposed fuzzy clustering validity evaluation method can overcome the shortcoming of single clustering validity function, and can get the optimal clustering number more accurately for different data sets.

To investigate the optimal androgen concentration for culturing Hetian sheep wool follicle and to detect effects of androgen concentration on wool follicle cell proliferation and apoptosis using immunofluorescence labeling and real-time quantitative fluorescence determinations of wool keratin-associated protein gene expression levels. Wool follicles were isolated by microdissection and wool follicles and skin pieces were cultured in various concentrations of dihydrotestosterone (DHT) in culture medium. Next, daily lengthwise growth measurements of wool follicles were obtained using a microscopic micrometer. Cultured Hetian wool follicles were stained using the SACPIC method to reveal wool follicle structure, while sheep skin slices were used to observe cell proliferation by immunostaining and cell apoptosis using the TUNEL method. At the molecular biological level, keratin-associated protein (Kap) gene expression was studied using wool follicles cultured for various numbers of days in vitro. Effects of androgen concentrations on Hetian wool follicle growth and development were experimentally studied. EdU proliferation assays revealed that androgen promoted cell proliferation within wool follicle dermal papillae. TUNEL apoptosis detection demonstrated that androgen treatment could delay cell apoptosis. Quantitative reverse transcription polymerase chain reaction (qPCR) results demonstrated that gene expression level patterns of Hetian mountain sheep super-high sulfur protein. Kap1.1, KIF1.2, Kap2.12 and Kap4.2 gene expression level of the mountainous experimental group was significantly higher than plains Hetian sheep. An androgen concentration of 100 nM can promote the growth of Hetian wool follicle cells in vitro, resulting in overexpression of some genes of the Kap family. Resumo Investigar a concentração ideal de andrógenos em cultura de folículos pilosos de carneiro Hetiano e detectar os efeitos da concentração de andrógenos na proliferação e apoptose de células foliculares, por meio de imunofluorescência e de determinação quantitativa, em tempo real, da fluorescência dos níveis de expressão gênica de proteína associada à queratina. Folículos pilosos foram isolados por microdissecção, e folículos de lã e pedaços de pele foram cultivados em várias concentrações de di-hidrotestosterona (DHT) em meio de cultura. Em seguida, medições diárias de crescimento longitudinal dos folículos capilares foram obtidas usando um micrômetro microscópico. Folículos de lã cultivados de Hetianos foram corados pelo método SACPIC para revelar a estrutura do folículo piloso, enquanto fatias de pele de carneiro foram usadas para observar a proliferação celular por imunocoloração e apoptose celular por meio do método TUNEL. Em âmbito da biologia molecular, a expressão gênica da proteína associada à queratina (Kap) foi estudada usando folículos capilares cultivados por vários dias, in vitro. Os efeitos das concentrações de andrógenos no crescimento e desenvolvimento dos folículos de lã de Hetianos foram estudados experimentalmente. Ensaios de proliferação de EdU revelaram que o andrógeno promoveu a proliferação celular dentro das papilas dérmicas do folículo piloso. A detecção de apoptose por TUNEL demonstrou que o tratamento com andrógeno poderia atrasar a apoptose celular. Os resultados da reação em cadeia da polimerase transcrição reversa quantitativa (qPCR) demonstraram que os padrões de expressão gênica da proteína de enxofre Kap1.1, KIF1.2, Kap2.12 e Kap4.2 foram significativamente maiores no grupo de ovinos Hetianos de montanha. Uma concentração de androgênio de 100 nM pode promover o crescimento de células foliculares de lã de Hetianos in vitro, resultando na superexpressão de alguns genes da família Kap.

Epitaxial layers of GaN and InGaN/GaN multi-quantum well light emitting diodes (LEDs) were prepared both on cone-shaped patterned sapphire substrates and conventional sapphire substrates. The mechanism of nucleation of GaN epilayers was studied using metallographic and atomic force microscope images of the surface of GaN epilayers, and the internal factors of cone-shaped patterned sapphire substrates that accelerate GaN transverse growth and improve the quality of epitaxial layers were analyzed. The microstructural properties of GaN epitaxial layers grown on a patterned sapphire substrate were studied in detail using transmission electron microscopy to determine the distribution and growth. The surface morphology of p-GaN was characterized by scanning electron microscopy, and some other information about the defects was obtained. The full width at half maximum of electroluminescence spectra of LED grown on the patterned sapphire substrate is small, and its monochromaticity is good.

Anaplastic lymphoma kinase-positive (ALK+) and ROS proto-oncogene 1 (ROS1)-positive (ROS1+) lung cancers have been reported to be associated with an elevated risk of thromboembolic events. This study aimed to assess the long-term risk of developing thromboembolism (TE) in ROS1+ lung cancer and to compare it with other oncogenic drivers in the Asian population.We retrospectively enrolled a cohort of ROS1+ lung adenocarcinoma in a medical center in Taiwan and a comparison cohort of ALK+ and epidermal growth factor receptor-positive (EGFR+) lung cancers. Venous and arterial TEs were identified throughout the cancer course, and the incidence rate was calculated.We enrolled 44 ROS1+, 98 ALK+, and 168 EGFR+ non-small-cell lung cancer (NSCLC) patients. A total of 11 (25%), 36 (36.7%), and 38 (22.6%) patients in the ROS1, ALK, and EGFR cohorts, respectively, were diagnosed with thromboembolic events throughout the follow-up course of the disease (P = 0.042). The incidence rates were 99.0, 91.9, and 82.5 events per 1000 person-years for the ROS1, ALK, and EGFR cohorts, respectively. The majority of thrombosis events in the ROS1 (91.6%) and ALK (85.4%) cohorts were venous. On the contrary, 43.2% of thromboembolic events were arterial in the EGFR cohort. A higher proportion of thromboembolic events were noted during cancer diagnosis in the ROS1 cohort (36.3%) than in the ALK (16.7%) and EGFR (10.5%) cohorts. The stage was the only clinical variable associated with thromboembolic risk. There was a significant difference in survival between patients with and without TE in the EGFR cohort, but not in the ALK and ROS1 cohorts.Although ROS1+ and ALK+ NSCLCs had a higher cumulative incidence of TE than EGFR+ NSCLC, the person-year incidence rates were similar among the three groups. EGFR-mutated NSCLC had more arterial events. Nevertheless, ALK+ lung cancer had higher venous events than EGFR-mutated lung cancer.