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“Essentials of Biotechnology”来华留学英语授课品牌课程建设纪实 被引量:1
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作者 夏小乐 冯守帅 +1 位作者 辛瑜 王武 《教育教学论坛》 2018年第51期244-245,共2页
经过十多年的建设,"Essentials of Biotechnology"已建设成为江南大学乃至江苏省来华留学生英语授课品牌课程。该课程针对来华留学生学科背景有较大差异,英语能力参差不齐和课程知识涉及面广,知识点较多,理论性强等问题,在原... 经过十多年的建设,"Essentials of Biotechnology"已建设成为江南大学乃至江苏省来华留学生英语授课品牌课程。该课程针对来华留学生学科背景有较大差异,英语能力参差不齐和课程知识涉及面广,知识点较多,理论性强等问题,在原有双语课程教学的基础上,通过优化教材和教学内容,打造双向教学模式和建设多元评价体系并持续改进,构建了多层次启发式、互动、研讨相结合的复合教学体系,显著增强留学生专业基础知识水平和自主学习能力,为后续课程学习和研究工作的开展奠定了良好的基础。教学实践结果表明,该教学体系对提高该类课程的学习成效和课程质量,具有较为显著的示范效应。 展开更多
关键词 essentials of BIOTECHNOLOGY 留学生品牌课程 双向教学模式 多元评价体系
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HP Storage Essentials
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《软件世界》 2007年第17期58-58,共1页
HP Storage Essentials解决方案服务可帮助客户安装、集成和优化其存储区域管理解决方案的效率和性能,面向服务器和存储网络的统一管理平台将帮助企业大大缩短解决问题的时间,更加有效地进行故障排除和事件关联,同时降低总体管理成本。
关键词 HP STORAGE essentials 企业 故障排除 事件关联 信息化
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Potential Use of Essentials Oils to Control Fruitlet Core Rot (FCR) in Pineapple (Queen Victoria Variety) in Reunion Island
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作者 Marc Chillet Angélique Hoareau +1 位作者 Mathilde Hoarau Jérome Minier 《American Journal of Plant Sciences》 2020年第11期1671-1681,共11页
Fruitlet Core Rot (FCR) is one of the major postharvest diseases of pineapple (<i><span style="font-family:Verdana;">Ananas comosus</span></i><span style="font-family:Verdana;... Fruitlet Core Rot (FCR) is one of the major postharvest diseases of pineapple (<i><span style="font-family:Verdana;">Ananas comosus</span></i><span style="font-family:Verdana;"> var. </span><i><span style="font-family:Verdana;">comosus</span></i><span style="font-family:Verdana;">), especially on the prone variety Queen Victoria cultivated in Reunion Island. This aggressive disease is generally due to two pathogens: </span><i><span style="font-family:Verdana;">Fusarium ananatum</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Thalaromyces stolii</span></i><span style="font-family:Verdana;">, and needs to be controlled during postharvest. In Reunion Island, </span><i><span style="font-family:Verdana;">F. ananatum</span></i><span style="font-family:Verdana;"> is the principal causal agent impacting fruit exportation. Fruit produced for the export market is generally treated with chemicals. This type of postharvest treatment is not in line with consumer expectations, as consumers prefer fruits treated with nonharmful and natural products. The objective of this work was to study alternative postharvest treatments using the fungitoxic properties of essential oils and their ability to elicit the resistance mechanisms of the fruit. Six EAs were tested </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> on mycelial growth of </span><i><span style="font-family:Verdana;">F. ananatum</span></i><span style="font-family:Verdana;">. Whether by volatilization or included in the culture medium, some essential oils such as thymol, eugenol, geraniol and the carvone/menthol mixture have a strong fungistatic effect. But only thymol has a fungitoxic effect. The thymol, a natural molecule synthesized by thyme (</span><i><span style="font-family:Verdana;">Thymus vulgaris</span></i><span style="font-family:Verdana;"> L. </span><i><span style="font-family:Verdana;">thymoliferum</span></i><span style="font-family:Verdana;">) is the more effective </span><i><span style="font-family:Verdana;">in vitro </span></i><span style="font-family:Verdana;">and is the strongest potential to be used in postharvest treatment. Thymol, prepared at 0.025% in a terpene solvent that acts as a penetrating agent, was tested </span><i><span style="font-family:Verdana;">in vivo</span></i><span style="font-family:Verdana;"> with inoculated fruits. The treatment was effective only on necrosis development from the upper part of the fruits. Pineapple polyphenol biosynthesis appears to have been suppressed by thymol treatment. Results and opportunities for this treatment are discussed. Additional experiments must be carried out in order to decide on the advisability of this type of treatment.</span> 展开更多
关键词 Essential Oils Fruitlet Core Rot PINEAPPLE Postharvest Treatment THYMOL
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托福®Essentials™考试正式上线
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作者 张影 《留学》 2021年第10期20-21,共2页
2021年5月19日,美国教育考试服务中心(ETS)举办全球线上发布会,正式宣布推出托福®Essentials™考试。托福®Essentials™考试是一项全新的英语能力测评考试,是托福®家族系列测评中仅次于15年前推出的托福iBT考试的第二个高... 2021年5月19日,美国教育考试服务中心(ETS)举办全球线上发布会,正式宣布推出托福®Essentials™考试。托福®Essentials™考试是一项全新的英语能力测评考试,是托福®家族系列测评中仅次于15年前推出的托福iBT考试的第二个高利害英语语言能力测试。该考试将于2021年6月17日(星期四)向中国考生开放报名,首次考试将于8月21日(星期六)进行。 展开更多
关键词 能力测评 ESSENTIAL 家族系列 托福 发布会 考试
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托福Essentials对我国中学英语考试的启示
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作者 庄亮亮 《中小学外语教学》 北大核心 2023年第13期60-64,F0003,共6页
本文从基本情况、考试内容和成绩报告三个方面对托福Essentials进行了研究。研究发现:(1)该考试较为便捷,考生在家便可进行考试,多阶段自适应技术有效减少了试题数量,缩短了考试时间;(2)试题任务有较强的真实性和交互性;(3)成绩报告重... 本文从基本情况、考试内容和成绩报告三个方面对托福Essentials进行了研究。研究发现:(1)该考试较为便捷,考生在家便可进行考试,多阶段自适应技术有效减少了试题数量,缩短了考试时间;(2)试题任务有较强的真实性和交互性;(3)成绩报告重点突出,内容翔实,能有效引导考生和社会正确使用考试结果。托福Essentials涵盖了从入门级到精通级的所有能力层级,代表了语言测试计算机化的发展趋势,对我国的中学英语考试形式与内容改革具有一定的启示。 展开更多
关键词 托福essentials 英语考试 计算机化
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Effects of Supplemental Glutamine and Lysine on Growth Performance of Broiler Chickens
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作者 Ali F. Alsogair Naif M. Alhawiti Samuel N. Nahashon 《Open Journal of Animal Sciences》 2024年第2期101-122,共22页
The optimum levels of Lysine and Glutamine needed for growth performance and maintenance of the chicken broilers were evaluated in a randomized 3 × 4 factorial arrangement of dietary treatments. The battery cages... The optimum levels of Lysine and Glutamine needed for growth performance and maintenance of the chicken broilers were evaluated in a randomized 3 × 4 factorial arrangement of dietary treatments. The battery cages measured 99 × 66 × 25 cm that can be sufficient for 5 birds. Day old Chicken broilers totaling 180 were assigned to dietary treatments comprising of 3 concentrations of Lysine (0.85, 1.14, and 1.42) each in combination with 4 concentrations of Glutamine (0, 1, 2, and 3). Each dietary treatment was replicated 3 times and each replication had 5 birds. The birds were given feed and water ad libitum with a 23-hour light regimen for a period of 4 weeks. Then, the experimental birds were evaluated for body weight gain, feed consumption, and feed conversion in order to determine their optimum requirement for dietary Lysine and Glutamine. Based on the findings of this study, the highest performance was observed in birds fed the diet supplemented with 1.42 lysine and 1% glutamine, but the highest improvement in feed conversion was observed in diet contain 1.14 and 1.42 with 1% and 3% glutamine, respectively. Birds fed 1.42 lysine and 1% glutamine had the highest total body weight gain and feed consumption. The lysine requirements in the diet for Chicken are between 1.14 and 1.42 with glutamine level of 1%. 展开更多
关键词 Broiler Chickens LYSINE GLUTAMINE Amino Acid Dietary Protein essentials AAs Non-Essential Amino Acids
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Key Points and Difficulties in the Management of a New Guangzhou 12th People’s Hospital Branch
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作者 Liya Fang 《Journal of World Architecture》 2024年第3期63-71,共9页
During the 13th Five-Year Plan period,to improve medical and health services,the Guangzhou Municipal government invested billions in medical construction.During that time,Guangzhou was renewing its approval procedures... During the 13th Five-Year Plan period,to improve medical and health services,the Guangzhou Municipal government invested billions in medical construction.During that time,Guangzhou was renewing its approval procedures for construction projects,and the COVID-19 outbreak changed the requirements of hospital construction.In addition to focusing more on spatial planning and layout,the integration of specialized departments,large-scale medical equipment,and numerous intelligent systems increased the complexity of hospital construction projects.The success of these projects often hinges on the quality of the management team.If a hospital construction project manager lacks experience and an understanding of the project’s key aspects,they may struggle with organization,management,and problem-solving,leading to rework,resource waste,and delays.This paper uses the construction of a new Guangzhou 12th People’s Hospital branch as an example to describe the key points and difficulties in each stage of project construction and proposes solutions for the management of similar projects in the future. 展开更多
关键词 Hospital construction project Project management Management essentials
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Causal associations between gastroesophageal reflux disease and essential hypertension: A bidirectional Mendelian randomization study 被引量:1
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作者 Ning Wei Ming-Hui Liu Yu-Hu Song 《World Journal of Clinical Cases》 SCIE 2024年第5期880-890,共11页
BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to invest... BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to investi-gate the causal link between GERD and essential hypertension.METHODS Eligible single nucleotide polymorphisms(SNPs)were selected,and weighted median,inverse variance weighted(IVW)as well as MR egger(MR-Egger)re-gression were used to examine the potential causal association between GERD and hypertension.The MR-Pleiotropy RESidual Sum and Outlier analysis was used to detect and attempt to reduce horizontal pleiotropy by removing outliers SNPs.The MR-Egger intercept test,Cochran’s Q test and“leave-one-out”sen-sitivity analysis were performed to evaluate the horizontal pleiotropy,heterogen-eities,and stability of single instrumental variable.RESULTS IVW analysis exhibited an increased risk of hypertension(OR=1.46,95%CI:1.33-1.59,P=2.14E-16)in GERD patients.And the same result was obtained in replication practice(OR=1.002,95%CI:1.0008-1.003,P=0.000498).Meanwhile,the IVW analysis showed an increased risk of systolic blood pressure(β=0.78,95%CI:0.11-1.44,P=0.021)and hypertensive heart disease(OR=1.68,95%CI:1.36-2.08,P=0.0000016)in GERD patients.Moreover,we found an decreased risk of Barrett's esophagus(OR=0.91,95%CI:0.83-0.99,P=0.043)in essential hypertension patients.CONCLUSION We found that GERD would increase the risk of essential hypertension,which provided a novel prevent and therapeutic perspectives of essential hypertension. 展开更多
关键词 Gastroesophageal reflux disease Essential hypertension Hypertensive heart disease Mendelian randomization study
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Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets
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作者 Chang Cui Yulong Wei +9 位作者 Yibo Wang Wen Ma Xiaoyu Zheng Jun Wang Ziwei Ma Caichi Wu Licui Chu Shihai Zhang Wutai Guan Fang Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期878-897,共20页
Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been ful... Background The benefits of combining benzoic acid and essential oils(BAO)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been fully elucidated.Previous research has primarily focused on the reparative effects of BAO on intestinal injury,while neglecting its potential in enhancing intestinal stress resistance.Methods In this study,we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental procedure.Piglets were pre-supplemented with BAO for 14 d,followed by a challenge with LPS or saline to collect blood and intestinal samples.Results Our findings demonstrated that BAO supplementation led to significant improvements in piglets’final weight,average daily gain,and feed intake/body gain ratio.Additionally,BAO supplementation positively influenced the composition of intestinal microbiota,increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota,Prevotella and Oscillospira.Furthermore,BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge.This was evidenced by elevated levels of T-AOC,SOD,and GSH,as well as decreased levels of MDA,TNF-α,and IL-6 in the plasma.Moreover,piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity,as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts.Further analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway.Additionally,the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with BAO.Conclusions In summary,our study demonstrates that pre-supplementation of BAO enhances the anti-stress capacity of weaned piglets by improving intestinal microbiota composition,reinforcing the intestinal barrier,and enhancing antioxidative and anti-inflammatory capabilities.These effects are closely associated with the activation of Nrf2 and TLR4/NF-κB/MAPK signaling pathways. 展开更多
关键词 ANTI-STRESS Benzoic acid Essential oils INTESTINE LPS Weaned piglets
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Establishment of a system for screening and identification of novel bactericide targets in the plant pathogenic bacterium Xanthomonas oryzae pv. oryzae using Tn-seq and SPR
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作者 Chaoyue Pang Ling Jin +9 位作者 Haoyu Zang Damalk Saint-Claire SKoklannou Jiazhi Sun Jiawei Yang Yongxing Wang Liang Xu Chunyan Gu Yang Sun Xing Chen Yu Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1580-1592,共13页
Xanthomonas spp. cause severe bacterial diseases. However, effective strategies for prevention and management of these diseases are scarce. Thus, it is necessary to improve the efficiency of control of diseases caused... Xanthomonas spp. cause severe bacterial diseases. However, effective strategies for prevention and management of these diseases are scarce. Thus, it is necessary to improve the efficiency of control of diseases caused by Xanthomonas. In this study, Xanthomonas oryzae pv. oryzae(Xoo), which causes rice bacterial leaf blight, has been studied as a representative. A transposon insertion library of Xoo, comprising approximately 200,000 individual insertion mutants, was generated. Transposon sequencing data indicated that the mariner C9 transposase mapped at 35.7–36.4% of all potential insertion sites, revealing 491 essential genes required for the growth of Xoo in rich media. The results show that, compared to the functions of essential genes of other bacteria, the functions of some essential genes of Xoo are unknown, 25 genes might be dangerous for the Xanthomonas group, and 3 are specific to Xanthomonas. High-priority candidates for developing broad-spectrum, Xanthomonas-specific, and environment-friendly bactericides were identified in this study. In addition, this study revealed the possible targets of dioctyldiethylenetriamine using surface plasmon resonance(SPR) in combination with high performance liquid chromatography–mass spectrometry(HPLC–MS). The study also provided references for the research of some certain bactericides with unknown anti-bacterial mode of action. In conclusion, this study urged a better understanding of Xanthomonas,provided meaningful data for the management of bacterial leaf blight, and disclosed selected targets of a novel bactericide. 展开更多
关键词 rice bacterial leaf blight XANTHOMONAS essential genes Tn-seq dioctyldiethylenetriamine
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Oxygen is an essential gasotransmitter directly sensed via protein gasoreceptors
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作者 Savani Anbalagan 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第2期189-193,共5页
The current restrictive criteria for gasotransmitters exclude oxygen(O_(2))as a gasotransmitter in vertebrates.In this manuscript,I propose a revision of gasotransmitter criteria to include O_(2) per se as a signaling... The current restrictive criteria for gasotransmitters exclude oxygen(O_(2))as a gasotransmitter in vertebrates.In this manuscript,I propose a revision of gasotransmitter criteria to include O_(2) per se as a signaling molecule and'essential gasotransmitter'for vertebrates.This revision would enable us to search for protein-based O_(2)-binding sensors(gasoreceptors)in all cells in the brain or other tissues rather than specialized tissues such as the carotid body or gills.If microorganisms have protein-based O_(2)-binding sensors or gasoreceptors such as DosP or FixL or FNR with diverse signaling domains,then eukaryotic cells must also have O_(2)-binding sensors or gasoreceptors.Just as there are proteinbased receptor(s)for nitric oxide(GUCY1A,GUCY1B,CLOCK,NR1D2)in cells of diverse tissues,it is reasonable to consider that there are protein-based receptors for O_(2) in cells of diverse tissues as well.In mammals,O_(2) must be acting as a gasotransmitter or gaseous signaling molecule via protein-based gasoreceptors such as androglobin that very likely mediate acute sensing of O_(2).Accepting O_(2) as an essential gasotransmitter will enable us to search for gasoreceptors not only for O_(2) but also for other nonessential gasotransmitters such as hydrogen sulfide,ammonia,methane,and ethylene.It will also allow us to investigate the role of environment-derived metal ions in acute gas(or solute)sensing within and between organisms.Finally,accepting O_(2) per se as a signaling molecule acting via gasoreceptors will open up the field of gasocrinology. 展开更多
关键词 essential gasotransmitter gasocrine gasoreceptor gasocrinology
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Magnetic resonance-guided focused ultrasound for essential tremor:a prospective,single center,single-arm study
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作者 Rui Zong Xuemei Li +10 位作者 Chunyu Yin Jianfeng He Dekang Zhang Xiangbing Bian Lichao Huang Jiayou Zhou Zhipei Ling Lin Ma Xin Lou Longsheng Pan Xinguang Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2075-2080,共6页
The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided foc... The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided focused ultrasound system in Chinese mainland was installed at the First Medical Center of the PLA General Hospital.This prospective,single center,open-label,single-arm study was part of a worldwide prospective multicenter clinical trial(ClinicalTrials.gov Identifier:NCT03253991)conducted to confirm the safety and efficacy of magnetic resonance-guided focused ultrasound for treating essential tremor in the local population.From 2019 to 2020,10 patients with medication refractory essential tremor were recruited into this open-label,single arm study.The treatment efficacy was determined using the Clinical Rating Scale for Tremor.Safety was evaluated according to the incidence and severity of adverse events.All of the subjects underwent a unilateral thalamotomy targeting the ventral intermediate nucleus.At the baseline assessment,the estimated marginal mean of the Clinical Rating Scale for Tremor total score was 58.3±3.6,and this improved after treatment to 23.1±6.4 at a 12-month follow-up assessment.A total of 50 adverse events were recorded,and 2 were defined as serious.The most common intraoperative adverse events were nausea and headache.The most frequent postoperative adverse events were paresthesia and equilibrium disorder.Most of the adverse events were mild and usually disappeared within a few days.Our findings suggest that magnetic resonance-guided focused ultrasound for the treatment of essential tremor is effective,with a good safety profile,for patients in Chinese mainland. 展开更多
关键词 efficacy essential tremor magnetic resonance-guided focused ultrasound(MRgFUS) movement disorder safety stereotactic therapy THALAMOTOMY ventral intermediate nucleus
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A verifiable essential secret image sharing scheme based on HLRs(VESIS-(t,s,k,n))
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作者 Massoud Hadian Dehkordi Seyed Taghi Farahi Samaneh Mashhadi 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第2期388-410,共23页
In traditional secret image sharing schemes,a secret image is shared among shareholders who have the same position.But if the shareholders have two different positions,essential and non‐essential,it is necessary to u... In traditional secret image sharing schemes,a secret image is shared among shareholders who have the same position.But if the shareholders have two different positions,essential and non‐essential,it is necessary to use essential secret image sharing schemes.In this article,a verifiable essential secret image sharing scheme based on HLRs is proposed.Shareholder's share consists of two parts.The first part is produced by the shareholders,which prevents the fraud of dealers.The second part is a shadow image that is produced by using HLRs and the first part of share.The verification of the first part of the shares is done for the first time by using multilinear and bilinear maps.Also,for verifying shadow images,Bloom Filters are used for the first time.The proposed scheme is more efficient than similar schemes,and for the first part of the shares,has formal security. 展开更多
关键词 Bloom Filter CRYPTOGRAPHY Essential Secret Image Sharing Verifiability
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Essential proteins identification method based on four-order distances and subcellular localization information
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作者 卢鹏丽 钟雨 杨培实 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期765-772,共8页
Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have b... Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have been proposed to identify essential proteins. Unfortunately, most methods based on network topology only consider the interactions between a protein and its neighboring proteins, and not the interactions with its higher-order distance proteins. In this paper, we propose the DSEP algorithm in which we integrated network topology properties and subcellular localization information in protein–protein interaction(PPI) networks based on four-order distances, and then used random walks to identify the essential proteins. We also propose a method to calculate the finite-order distance of the network, which can greatly reduce the time complexity of our algorithm. We conducted a comprehensive comparison of the DSEP algorithm with 11 existing classical algorithms to identify essential proteins with multiple evaluation methods. The results show that DSEP is superior to these 11 methods. 展开更多
关键词 protein–protein interaction(PPI)network essential proteins four-order distances subcellular localization information
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Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam
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作者 Nguyen Quang Hung Nguyen Thanh Tung +7 位作者 Nguyen Phuong Hanh Chu Thi Thu Ha Nguyen Thi Nhung Nguyen Thai An Vu Xuan Giang Luong Van Hao Oleh Koshovyi Ain Raal 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1677-1687,共11页
Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of Vietnam.The yields of EOs from materials ranged from 0.03%(root EO of Angelic... Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of Vietnam.The yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identification of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the oils.In EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant monoterpenes.Sabinene appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present study.These databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam. 展开更多
关键词 Apiaceae essential oil TERPENOIDS gaschromatography-mass spectrometry
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Profiles of the Headspace Volatile Organic and Essential Oil Compounds from the Tunisian Cardaria draba (L.) Desv. and Its Leaf and Stem Epidermal Micromorphology
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作者 Wissal Saadellaoui Samiha Kahlaoui +6 位作者 Kheiria Hcini Abir Haddada Noomene Sleimi Roberta Ascrizzi Guido Flamini Fethia Harzallah-Skhiri Sondes Stambouli-Essassi 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期725-744,共20页
In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total... In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatileorganic compounds (96.7%–98.9%) were identified;4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones,1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the maingroup, representing 49.5%–84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane(44.5%–76.2%) reaching the highest relative percentages. Forty-two compounds were determined in thetwo fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal componentswere hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl-2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermisusing light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces andnearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes wereanisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandulartrichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones wereidentified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatalindex (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essentialoil compounds can be used to characterize this species, and the various epidermis micromorphologicalfeatures are very useful for biosystematics taxonomic studies within Brassicaceae. 展开更多
关键词 Cardaria draba aroma profile essential oils EPIDERMIS TRICHOMES
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Antibacterial,antioxidant and antiproliferation activities of essential oils and ethanolic extracts from Chinese mugwort(Artemisia vulgaris L.)leaf in Shanxi
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作者 Hu-Tan-Xian Zhang Feng-Ru Lyu +5 位作者 Jia-Tong He Chen-Yu Liu Zheng-Yang Zhou Rui-Jie Wu Zi-Qing Zhao He Li 《Traditional Medicine Research》 2024年第1期47-56,共10页
Background:Artemisia vulgaris,a medicinal aromatic plant,is widely used as a food item,tonic pharmaceutical,and cosmetic industry additive owing to its antibacterial,antihypertensive,hepatoprotective,antioxidant,and a... Background:Artemisia vulgaris,a medicinal aromatic plant,is widely used as a food item,tonic pharmaceutical,and cosmetic industry additive owing to its antibacterial,antihypertensive,hepatoprotective,antioxidant,and antispasmodic properties.But the effect of different geographic locations on the chemical composition and bioactivities of its extracts is unclear.Methods:Biological activities of essential oils and ethanol extracts of three varieties of Artemisia vulgaris leaves,which are grown in Shanxi province China,were studied.Results:Gas chromatography-mass spectrometry analysis revealed that the main components of essential oils were terpenes and ketones.Essential oils and ethanol extract of Artemisia vulgaris leaves possessed good antioxidant activities,and their half maximal inhibitory concentrations determined using 1,1-diphenyl-2-picrylhydrazyl and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate)assays were 57.0 and 22.9μg/mL,respectively.The essential oils also exhibited remarkable antibacterial activity against three foodborne pathogenic bacterial strains.The ethanol extract presented a high anticancer activity against the MGC-803 human gastric cancer cell line.Conclusion:These biological activities were well correlated with the composition of the extract and EOs,which in turn is affected by the genetic composition of Artemisia vulgaris and geographic location and diverse climatic condition under which it is grown.These findings demonstrate the remarkable potential of Artemisia vulgaris as a valuable source of antioxidant,antibacterial,and anticancer agents. 展开更多
关键词 Artemisia vulgaris essential oils ethanol extracts ANTIOXIDANT ANTIPROLIFERATION
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Identification of Secondary Metabolites in Tunisian Tilia platyphyllos Scop.Using MALDI-TOF and GC-MS
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作者 Ayda Khadhri Mohamed Mendili +2 位作者 Marwa Bannour-Scharinger Eric Masson Antonio Pizzi 《Journal of Renewable Materials》 EI CAS 2024年第4期827-842,共16页
This study is the first to evaluate the phytochemical content and biological properties of Tunisian T.platyphyllos Scop.A total of 23 compounds of essential oils were identified by gas chromatography-mass spectrometry... This study is the first to evaluate the phytochemical content and biological properties of Tunisian T.platyphyllos Scop.A total of 23 compounds of essential oils were identified by gas chromatography-mass spectrometry(GC-MS)analysis of bracts and fruit extracts.The results show that oxygenated monoterpenes were the dominant class of essential oils.The phenolic composition was investigated by matrix-assisted laser desorption/ionizationtime of flight(MALDI-TOF).The analysis showed that the chemical profiles of the ethanolic extracts of bracts and fruits are substantially similar.The highest polyphenol content was found in the ethanolic extracts of the fruits(7.65 mg gallic acid equivalents(GAE).g−1 on dry weight(DW).As for the antioxidant capacity,it was recorded in the essential oils of the fruits(IC_(50)=0.91 mg.mL^(−1)).The results obtained showed that the antioxidant activity of the fruit essential oil was higher than that of the ethanol extract.The fruit essential oil was also found to have the highest reducing power(IC_(50)=0.67 mg.mL^(−1)).In terms of iron-chelating power,fruit essential oil has the highest chelating power(IC_(50)=2.03 mg.mL^(−1)).Compared to the ethanolic extract,the essential oil had the maximum antioxidant capacity.The enzymatic activity of acetylcholinesterase(AChE)inhibition of the essential oil from T.platyphyllos bracts had the most potent inhibitory effect(IC_(50)=0.77 mg.mL^(−1)),followed by the essential oil from the fruits(IC_(50)=0.95 mg.mL^(−1)).The results suggest that T.platyphyllos can be used as a potential source of naturally occurring bioactive compounds and antioxidants. 展开更多
关键词 T.platyphyllos antioxidant activity acetylcholinesterase inhibition essential oil MALDI-TOF GC-MS
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Cardioprotective Potential of Cymbopogon citratus Essential Oil against Isoproterenol-induced Cardiomyocyte Hypertrophy:Possible Involvement of NLRP3 Inflammasome and Oxidative Phosphorylation Complex Subunits
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作者 Xiao-yun DING Hao ZHANG +7 位作者 Yu-mei QIU Meng-die XIE Hu WANG Zheng-yu XIONG Ting-ting LI Chun-ni HE Wei DONG Xi-lan TANG 《Current Medical Science》 SCIE CAS 2024年第2期450-461,共12页
Objective:Cymbopogon citratus(DC.)Stapf is a medicinal and edible herb that is widely used for the treatment of gastric,nervous and hypertensive disorders.In this study,we investigated the cardioprotective effects and... Objective:Cymbopogon citratus(DC.)Stapf is a medicinal and edible herb that is widely used for the treatment of gastric,nervous and hypertensive disorders.In this study,we investigated the cardioprotective effects and mechanisms of the essential oil,the main active ingredient of Cymbopogon citratus,on isoproterenol(ISO)-induced cardiomyocyte hypertrophy.Methods:The compositions of Cymbopogon citratus essential oil(CCEO)were determined by gas chromatography-mass spectrometry.Cardiomyocytes were pretreated with 16.9µg/L CCEO for 1 h followed by 10µmol/L ISO for 24 h.Cardiac hypertrophy-related indicators and NLRP3 inflammasome expression were evaluated.Subsequently,transcriptome sequencing(RNA-seq)and target verification were used to further explore the underlying mechanism.Results:Our results showed that the CCEO mainly included citronellal(45.66%),geraniol(23.32%),and citronellol(10.37%).CCEO inhibited ISO-induced increases in cell surface area and protein content,as well as the upregulation of fetal gene expression.Moreover,CCEO inhibited ISO-induced NLRP3 inflammasome expression,as evidenced by decreased lactate dehydrogenase content and downregulated mRNA levels of NLRP3,ASC,CASP1,GSDMD,and IL-1β,as well as reduced protein levels of NLRP3,ASC,pro-caspase-1,caspase-1(p20),GSDMD-FL,GSDMD-N,and pro-IL-1β.The RNA-seq results showed that CCEO inhibited the increase in the mRNA levels of 26 oxidative phosphorylation complex subunits in ISO-treated cardiomyocytes.Our further experiments confirmed that CCEO suppressed ISO-induced upregulation of mt-Nd1,Sdhd,mt-Cytb,Uqcrq,and mt-Atp6 but had no obvious effects on mt-Col expression.Conclusion:CCEO inhibits ISO-induced cardiomyocyte hypertrophy through the suppression of NLRP3 inflammasome expression and the regulation of several oxidative phosphorylation complex subunits. 展开更多
关键词 Cymbopogon citratus essential oil cardiac hypertrophy NLRP3 inflammasome oxidative phosphorylation complex subunits
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Sparse-Grid Implementation of Fixed-Point Fast Sweeping WENO Schemes for Eikonal Equations
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作者 Zachary M.Miksis Yong-Tao Zhang 《Communications on Applied Mathematics and Computation》 EI 2024年第1期3-29,共27页
Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of ... Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of fast sweeping schemes,fixed-point fast sweeping methods use the Gauss-Seidel iterations and alternating sweeping strategy to cover characteristics of hyperbolic PDEs in a certain direction simultaneously in each sweeping order.The resulting iterative schemes have a fast convergence rate to steady-state solutions.Moreover,an advantage of fixed-point fast sweeping methods over other types of fast sweeping methods is that they are explicit and do not involve the inverse operation of any nonlinear local system.Hence,they are robust and flexible,and have been combined with high-order accurate weighted essentially non-oscillatory(WENO)schemes to solve various hyperbolic PDEs in the literature.For multidimensional nonlinear problems,high-order fixed-point fast sweeping WENO methods still require quite a large amount of computational costs.In this technical note,we apply sparse-grid techniques,an effective approximation tool for multidimensional problems,to fixed-point fast sweeping WENO methods for reducing their computational costs.Here,we focus on fixed-point fast sweeping WENO schemes with third-order accuracy(Zhang et al.2006[41]),for solving Eikonal equations,an important class of static Hamilton-Jacobi(H-J)equations.Numerical experiments on solving multidimensional Eikonal equations and a more general static H-J equation are performed to show that the sparse-grid computations of the fixed-point fast sweeping WENO schemes achieve large savings of CPU times on refined meshes,and at the same time maintain comparable accuracy and resolution with those on corresponding regular single grids. 展开更多
关键词 Fixed-point fast sweeping methods Weighted essentially non-oscillatory(WENO)schemes Sparse grids Static Hamilton-Jacobi(H-J)equations Eikonal equations
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