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Torsional behavior of triangular web profile (TRIWP) steel section by experimental study

Fatimah DE’NAN,Hazwani HASAN,Mohd Hanim OSMAN,Sariffudin SAAD

《结构与土木工程前沿（英文）》 2016年第10卷第4期页码 409-419 doi: 10.1007/s11709-016-0358-6

摘要： A triangular web profile (TriWP) is a modified section where the flanges are connected to a web plate of triangular profile. This study examined the torsional behavior of TriWP steel sections and compared to that of the flat web (FW) steel sections. Three types of specimen sizes were used: 180 mm × 75 mm × 5 mm × 2 mm, 200 mm × 100 mm × 8 mm × 6 mm, and 200 mm × 100 mm × 6 mm × 5 mm. All the specimens were loaded vertically until the maximum load was achieved and then the load was released. For both types of specimens, it was observed that the torsional rotation for bigger size [200 mm × 100 mm × 8 mm × 6 mm] were smaller than that of smaller size [180 mm × 75 mm × 5 mm × 2 mm] of the specimens. At the maximum torsional loading, the experimental result was compared to the theoretical calculation. The comparison showed that the percentage difference ranged from 1.10% to 16.80%. From the graph of torsional load versus rotational angle, the torsional rotation for all TriWP steel sections were smaller than that of the FW steel section under the same torsional loading i.e., 0.2 kNm and 1 kNm. The range between FW and TriWP were 3.74 to 71.83 at 0.2 kNm while 14.5 to 75.1 at 1.0 kNm. The findings were shown that the TriWP steel sections had better resistance against torsion in comparison to FW steel section.

关键词： corrugated web i-beam non uniform steel section torsion resistance torsion angle triangular web profile steel section

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Fatigue crack growth behavior of a 170 mm diameter stainless steel straight pipe subjected to combined torsion

《结构与土木工程前沿（英文）》 2021年第15卷第4期页码 905-913 doi: 10.1007/s11709-021-0683-2

摘要： In a nuclear powerplant, the rotary equipment, such as a pump directly fitted with hanger in the piping system, experiences torsional and bending loads. Higher crack growth rate occurs because of this torsional load in addition to the bending load. Hence, it is necessary to study the fatigue behavior of piping components under the influence of combined torsional and bending load. In this study, experimental fatigue life evaluation was conducted on a notched stainless steel SA312 Type 304LN straight pipe having an outer diameter of 170 mm. The experimental crack depth was measured using alternating current potential drop technique. The fatigue life of the stainless steel straight pipe was predicted using experiments, Delale and Erdogan method, and area-averaged root mean square–stress intensity factor approach at the deepest and surface points of the notch. Afterward, the fatigue crack growth and crack pattern were discussed. As a result, fatigue crack growth predicted using analytical methods are in good agreement with experimental results.

关键词： fatigue life Delale and Erdogan method RMS–SIF approach stainless steel torsion and bending load fatigue crack growth

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A compound load simulator based on zero-torsion parallel mechanisms

Jingjun YU, Wei LI, Xu PEI, Shusheng BI, Guanghua ZONG

《机械工程前沿（英文）》 2012年第7卷第1期页码 1-4 doi: 10.1007/s11465-012-0306-7

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几率波与量子效应的扭率问题

欧阳首承,李智兰,袁东升

《中国工程科学》 2005年第7卷第6期页码 1-6

摘要：

按曲率空间的扭率，对含有三阶非线性变量导数的Schrödinger变形等价程进行了数值分析，发现几率波的几率性原来是扭率的疏密流在特定条件下的准规则流，并为势场强度和粒子体元密度的相互作用与量子扭率效应项综合作用的结果；纯量子效应作用为非规则流。

关键词：扭率几率量子效应非线性不稳定曲率空间

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Prevalence of antifolate drug resistance markers in in China

《医学前沿（英文）》 2022年第16卷第1期页码 83-92 doi: 10.1007/s11684-021-0894-x

摘要： The dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) genes of Plasmodium vivax and antifolate resistance-associated genes were used for drug resistance surveillance. A total of 375 P. vivax isolates collected from different geographical locations in China in 2009–2019 were used to sequence Pvdhfr and Pvdhps. The majority of the isolates harbored a mutant type allele for Pvdhfr (94.5%) and Pvdhps (68.2%). The most predominant point mutations were S117T/N (77.7%) in Pvdhfr and A383G (66.8%) in Pvdhps. Amino acid changes were identified at nine residues in Pvdhfr. A quadruple-mutant haplotype at 57, 58, 61, and 117 was the most frequent (57.4%) among 16 distinct Pvdhfr haplotypes. Mutations in Pvdhps were detected at six codons, and the double-mutant A383G/A553G was the most prevalent (39.3%). Pvdhfr exhibited a higher mutation prevalence and greater diversity than Pvdhps in China. Most isolates from Yunnan carried multiple mutant haplotypes, while the majority of samples from temperate regions and Hainan Island harbored the wild type or single mutant type. This study indicated that the antifolate resistance levels of P. vivax parasites were different across China and molecular markers could be used to rapidly monitor drug resistance. Results provided evidence for updating national drug policy and treatment guidelines.

关键词： drug resistance antifolates molecular markers Plasmodium vivax China

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Metagenomic analysis on resistance genes in water and microplastics from a mariculture system

《环境科学与工程前沿（英文）》 2022年第16卷第1期页码 4-4 doi: 10.1007/s11783-021-1438-y

摘要：

Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants. Mariculture systems have been observed to host microplastics and antibiotic resistance genes (ARGs). However, more information on proliferation of ARGs and metal resistance genes (MRGs) in mariculture system at the presence of microplastics is needed.

关键词： Antibiotic resistance genes Metal resistance genes Metagenomic analysis Microplastics Mariculture

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Taking advantage of drug resistance, a new approach in the war on cancer

null

《医学前沿（英文）》 2018年第12卷第4期页码 490-495 doi: 10.1007/s11684-018-0647-7

摘要：

Identification of the driver mutations in cancer has resulted in the development of a new category of molecularly targeted anti-cancer drugs. However, as was the case with conventional chemotherapies, the effectiveness of these drugs is limited by the emergence of drug-resistant variants. While most cancer therapies are given in combinations that are designed to avoid drug resistance, we discuss here therapeutic approaches that take advantage of the changes in cancer cells that arise upon development of drug resistance. This approach is based on notion that drug resistance comes at a fitness cost to the cancer cell that can be exploited for therapeutic benefit. We discuss the development of sequential drug therapies in which the first therapy is not given with curative intent, but to induce a major new sensitivity that can be targeted with a second drug that selectively targets the acquired vulnerability. This concept of collateral sensitivity has hitherto not been used on a large scale in the clinic and holds great promise for future cancer therapy.

关键词： cancer drug resistance genetic screens senescence targeted therapy

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论零点振动能与Casimir力

黄志洵

《中国工程科学》 2008年第10卷第5期页码 63-69

摘要：

在真空中放置一对平行的金属板（间距很小），两板会由于一个微弱（可测出）的力而有相互靠近的趋势。这种Casimir效应可用量子理论中的零点能（ZPE）解释。科学家们都认为Casimir力存在，但对其产生的原因却有不同看法。空虚空间是否具有能量，其答案或许将决定宇宙的命运。在自然界和人类实验室中，有许多异常现象可用Casimir效应及挠场理论作出说明。

关键词：零点能零点场真空能 Casimir力挠场理论

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Targeting apoptosis to manage acquired resistance to third generation EGFR inhibitors

《医学前沿（英文）》 2022年第16卷第5期页码 701-713 doi: 10.1007/s11684-022-0951-0

摘要： A significant clinical challenge in lung cancer treatment is management of the inevitable acquired resistance to third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs), such as osimertinib, which have shown remarkable success in the treatment of advanced NSCLC with EGFR activating mutations, in order to achieve maximal response duration or treatment remission. Apoptosis is a major type of programmed cell death tightly associated with cancer development and treatment. Evasion of apoptosis is considered a key hallmark of cancer and acquisition of apoptosis resistance is accordingly a key mechanism of drug acquired resistance in cancer therapy. It has been clearly shown that effective induction of apoptosis is a key mechanism for third generation EGFR-TKIs, particularly osimertinib, to exert their therapeutic efficacies and the development of resistance to apoptosis is tightly associated with the emergence of acquired resistance. Hence, restoration of cell sensitivity to undergo apoptosis using various means promises an effective strategy for the management of acquired resistance to third generation EGFR-TKIs.

关键词： acquired resistance EGFR inhibitor apoptosis lung cancer

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Transmission of antibiotic resistance genes in agroecosystems: an overview

Jizheng HE, Zhenzhen YAN, Qinglin CHEN

《农业科学与工程前沿（英文）》 2020年第7卷第3期页码 329-332 doi: 10.15302/J-FASE-2020333

摘要：

The use of antibiotics in human medicine and animal husbandry has resulted in the continuous release of antibiotics into the environment, which imposes high selection pressure on bacteria to develop antibiotic resistance. The spread and aggregation of antibiotic resistance genes (ARGs) in multidrug-resistant pathogens is one of the most intractable clinical challenges. Numerous studies have been conducted to profile the patterns of ARGs in agricultural ecosystems, as this is closely related to human health and wellbeing. This paper provides an overview of the transmission of ARGs in agricultural ecosystems resulting from the application of animal manures and other organic amendments. The future need to control and mitigate the spread of antibiotic resistance in agricultural ecosystems is also discussed, particularly from a holistic perspective, and requires multiple sector efforts to translate fundamental knowledge into effective strategies.

关键词： agroecosystem antibiotic resistance public health soil-plant system

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swine manure with sulfamethoxazole and norfloxacin: Dynamics of microbial communities and evolution of resistance

《环境科学与工程前沿（英文）》 2021年第15卷第5期 doi: 10.1007/s11783-020-1342-x

摘要：

• SMX addition had negative effect on acetoclastic methanogens in mesophilic AD.

关键词： Pig manure Antibiotics Anaerobic digestion Resistance genes Microbial community

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Degradation of extracellular genomic, plasmid DNA and specific antibiotic resistance genes by chlorination

Menglu Zhang, Sheng Chen, Xin Yu, Peter Vikesland, Amy Pruden

《环境科学与工程前沿（英文）》 2019年第13卷第3期 doi: 10.1007/s11783-019-1124-5

摘要：

Extracellular DNA structure damaged by chlorination was characterized.

Integrity of extracellular ARG genetic information after chlorination was determined.

Typical chlorine doses will likely effectively diminish extracellular DNA and ARGs.

Plasmid DNA/ARGs were less readily broken down than genomic DNA.

The Bioanalyzer methodology effectively documented damage incurred to DNA.

关键词： Antibiotic resistance Antibiotic resistance genes (ARGs) Extracellular DNA/ARGs Chlorination

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Insulin resistance and the metabolism of branched-chain amino acids

null

《医学前沿（英文）》 2013年第7卷第1期页码 53-59 doi: 10.1007/s11684-013-0255-5

摘要：

Insulin resistance (IR) is a key pathological feature of metabolic syndrome and subsequently causes serious health problems with an increased risk of several common metabolic disorders. IR related metabolic disturbance is not restricted to carbohydrates but impacts global metabolic network. Branched-chain amino acids (BCAAs), namely valine, leucine and isoleucine, are among the nine essential amino acids, accounting for 35% of the essential amino acids in muscle proteins and 40% of the preformed amino acids required by mammals. The BCAAs are particularly responsive to the inhibitory insulin action on amino acid release by skeletal muscle and their metabolism is profoundly altered in insulin resistant conditions and/or insulin deficiency. Although increased circulating BCAA concentration in insulin resistant conditions has been noted for many years and BCAAs have been reported to be involved in the regulation of glucose homeostasis and body weight, it is only recently that BCAAs are found to be closely associated with IR. This review will focus on the recent findings on BCAAs from both epidemic and mechanistic studies.

关键词： branched-chain amino acids leucine isoleucine valine insulin resistance

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Immunometabolism: a new dimension in immunotherapy resistance

《医学前沿（英文）》 2023年第17卷第4期页码 585-616 doi: 10.1007/s11684-023-1012-z

摘要： Immune checkpoint inhibitors (ICIs) have demonstrated unparalleled clinical responses and revolutionized the paradigm of tumor treatment, while substantial patients remain unresponsive or develop resistance to ICIs as a single agent, which is traceable to cellular metabolic dysfunction. Although dysregulated metabolism has long been adjudged as a hallmark of tumor, it is now increasingly accepted that metabolic reprogramming is not exclusive to tumor cells but is also characteristic of immunocytes. Correspondingly, people used to pay more attention to the effect of tumor cell metabolism on immunocytes, but in practice immunocytes interact intimately with their own metabolic function in a way that has never been realized before during their activation and differentiation, which opens up a whole new frontier called immunometabolism. The metabolic intervention for tumor-infiltrating immunocytes could offer fresh opportunities to break the resistance and ameliorate existing ICI immunotherapy, whose crux might be to ascertain synergistic combinations of metabolic intervention with ICIs to reap synergic benefits and facilitate an adjusted anti-tumor immune response. Herein, we elaborate potential mechanisms underlying immunotherapy resistance from a novel dimension of metabolic reprogramming in diverse tumor-infiltrating immunocytes, and related metabolic intervention in the hope of offering a reference for targeting metabolic vulnerabilities to circumvent immunotherapeutic resistance.

关键词： immune cell immunometabolism metabolic reprogramming immunotherapy resistance tumor microenvironment immune checkpoint inhibitor