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MILD粉体燃烧技术研究进展与关键问题分析
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作者 吕俊复 冯乐乐 +1 位作者 吴玉新 张海 《煤炭学报》 EI CAS CSCD 北大核心 2024年第1期224-234,共11页
MILD燃烧是一种在中度或极度低氧环境下发生的温和燃烧模式,兼具高燃烧热利用率和极低NOx排放的优势,国际燃烧领域认为它是拥有巨大应用潜力的清洁燃烧技术之一。自1990年左右开展相关研究以来,对于实现气体燃料的MILD燃烧的相关技术已... MILD燃烧是一种在中度或极度低氧环境下发生的温和燃烧模式,兼具高燃烧热利用率和极低NOx排放的优势,国际燃烧领域认为它是拥有巨大应用潜力的清洁燃烧技术之一。自1990年左右开展相关研究以来,对于实现气体燃料的MILD燃烧的相关技术已相对成熟,而关于煤粉和生物质等固体燃料的MILD燃烧机制和实现条件的研究仍相对缺乏。基于高动量氧化剂射流来实现内部再循环,不再需要外部高温预热来建立MILD燃烧,极大拓宽了MILD燃烧的应用范围。从颗粒弥散、受热、着火、燃烧、污染物等方面概述了MILD粉体燃料燃烧的基础特性,由于颗粒的不均匀弥散和反应,煤粉等碳基固体燃料的MILD燃烧进程较气体燃料更复杂。高速射流MILD燃烧在增加点火延迟的同时也扩展了点火区和反应区,需要对燃烧各阶段的特征和机理开展系统研究。介绍了固体燃料MILD燃烧理论设计和装备研发领域所取得的研究成果,建议通过高精度数值模拟,改进现有燃煤锅炉燃烧器、调节工艺参数以匹配MILD燃烧模式,增加焦炭颗粒的停留时间以提高燃烬率,提高燃烧稳定性并抑制包括细颗粒物在内的各类污染物排放。基于互联能源系统的整体方法,推进MILD燃烧与各类新型燃烧技术的耦合研究,尤其加强煤粉、生物质与氢、氨等可燃气体共燃特性研究,助力能源转型。探究粉体MILD燃烧中的湍流两相流特征、湍流相间传热作用以及湍流-化学耦合作用是加深对粉体MILD燃烧理解的关键,涉及多变量分析和高精度模拟,是未来研究的重点和难点。 展开更多
关键词 低氧稀释燃烧(mild) 高速射流 煤燃烧 污染物 湍流
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Association between Placental Malaria and Severe Pre-Eclampsia in Two University Hospitals of Yaounde City
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作者 Ayissi Gregory Astrid Ruth Ndolo Kondo +10 位作者 Ndoumba Afouba Alice Noa Ndoua Claude Cyrille Essiben Félix Meka Esther Belinga Etienne Metogo Junie Engo Engo Samuel Désiré Bodo Edmond Lemaire Tchente Nguefack Charlotte Foumane Pascal Mboudou Emile Télésphore 《Open Journal of Obstetrics and Gynecology》 2024年第9期1488-1511,共24页
Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: T... Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: The objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. The patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: The mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10. 展开更多
关键词 mild pre-eclampsia Severe pre-eclampsia MALARIA Placental Lesions ASSOCIATION
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一类中立型随机积微分方程mild解的存在性
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作者 陈昭先 范虹霞 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期395-402,共8页
该文在Hilbert空间中研究了一类具有非瞬时脉冲的中立型随机积微分方程非局部问题mild解的存在性.利用预解算子理论、非紧性测度理论和Darbo不动点定理,建立了所研究问题mild解的存在性定理,丰富和发展了已有的相关结果.
关键词 预解算子 非瞬时脉冲 随机积微分方程 非紧性测度 mild
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NH_(3)/H_(2)掺混MILD燃烧及NO_(x)排放特性的数值模拟
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作者 刘祥涛 王国昌 +2 位作者 司济沧 李鹏飞 米建春 《洁净煤技术》 CAS CSCD 北大核心 2024年第8期107-116,共10页
化石能源的利用推动了人类社会的进步,但也造成了全球气候变化,威胁人类的生存与发展。在此背景下,氨和氢作为零碳燃料引起了人们的重视,但其燃烧利用面临诸多问题。MILD燃烧是一种新型燃烧方式,有望实现氨/氢混合燃料的清洁高效燃烧,... 化石能源的利用推动了人类社会的进步,但也造成了全球气候变化,威胁人类的生存与发展。在此背景下,氨和氢作为零碳燃料引起了人们的重视,但其燃烧利用面临诸多问题。MILD燃烧是一种新型燃烧方式,有望实现氨/氢混合燃料的清洁高效燃烧,但目前研究非常有限。采用数值模拟方法对预混NH_(3)/H_(2)射流火焰的MILD燃烧和排放特性进行研究。改变了射流中的氢气比例(X(H_(2))F)和当量比(Φ_(J)),并详细分析了温升、反应域、抬升高度、自由基浓度以及氮氧化物(NO_(x))排放等。结果表明,添加少量H_(2)可显著增强NH_(3)火焰的稳定性,降低自着火温度并消除火焰抬升。此外,X(H_(2))_(F)的增加能提高燃烧温度,加快H、O和OH自由基的产生,并使燃烧模式由MILD燃烧转变为高温燃烧。富燃料且氢气比例较低时,NH_(3)在燃烧前大量分解为H_(2),导致燃烧温度较高。关于NO_(x)排放,N_(2)O和NO是最主要来源,NO_(2)可忽略不计。整体上,N_(2)O和NO的排放随X(H_(2))_(F)的增加先升高再降低。当X(H_(2))_(F)较低时,N_(2)O的浓度峰值与排放量和NO相当。提高X(H_(2))_(F),温度升高,导致N_(2)O转化为NO和N_(2),因此NO变为主要的NO_(x)排放源。此外,富燃工况中,燃烧温度、OH浓度及射流对伴流中氧气的卷吸共同影响NO排放。 展开更多
关键词 氨/氢混合燃料 mild燃烧 当量比 燃烧特性 NO_(x)排放
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Interfacial reaction between AZ91D magnesium alloy melt and mild steel under high temperature 被引量:1
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作者 Jia-hong Dai Jian-yue Zhang +5 位作者 Bin Jiang Xiang-jun Xu Zhong-tao Jiang Hong-mei Xie Qing-shan Yang Guo-qing Zhang 《China Foundry》 SCIE EI CAS CSCD 2024年第2期159-167,共9页
The metallurgical quality control of magnesium(Mg)and Mg alloys in melting process is required to ensure a satisfied mechanical and corrosion performance,while the typical used steel crucible introduces impurities and... The metallurgical quality control of magnesium(Mg)and Mg alloys in melting process is required to ensure a satisfied mechanical and corrosion performance,while the typical used steel crucible introduces impurities and interfacial interaction during melting process.Therefore,a systematic study about impurities diffusion and interfacial interaction between molten Mg and steel is necessary.In the present study,the interfacial reaction between molten AZ91D Mg alloy and mild steel during melting process was investigated with the melting temperatures of 700℃,750℃ and 800℃.The results show that Al(Fe,Mn)intermetallic layer is the intermetallic primarily formed at the interfaces of AZ91D melt and mild steel.Meanwhile,Al_(8)(Mn,Fe)5is indexed between Al(Fe,Mn)and AZ91D.AlFe_(3)C appears between the mild steel and Al(Fe,Mn)at 700℃ and 750℃,but absent at 800℃ due to the increased solubility of carbon in Mg matrix.It is found that the growth of the intermetallic layer is controlled by diffusion mechanism,and Al and Mn are the dominant diffusing species in the whole interfacial reaction process.By measuring the thickness of different layers,the growth constant was calculated.It increases from 1.89(±0.03)×10^(-12)m^(2)·s^(-1)at 700℃ to 3.05(±0.05)×10^(-12)m^(2)·s^(-1)at 750℃,and 5.18(±0.05)×10^(-12)m^(2)·s^(-1)at 800℃.Meanwhile,the content of Fe is linearly increased in AZ91D with the increase of holding time at 700℃ and 750℃,while it shows a significantly increment after holding for 8 h at 800℃,indicating holding temperature is more crucial to determine the Fe content of AZ91D than holding time. 展开更多
关键词 AZ91D mild steel interface reaction intermetallic growth KINETICS
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天然气增氧MILD燃烧及NO排放特性研究
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作者 孔俊峰 谢逸豪 +4 位作者 刘宇谦 方永旭 武学谦 徐顺塔 刘豪 《能源与环保》 2024年第4期138-145,151,共9页
将MILD(Moderate or Intensive Low-Oxygen Dilution)燃烧和增氧燃烧相结合,以实现天然气燃烧过程中低CO_(2)和NO排放。基于0.58 MW工业炉,开展了空气预混增氧方式下天然气MILD燃烧及NO排放特性模拟研究,分析了氧气浓度(19.5%~30.0%)和... 将MILD(Moderate or Intensive Low-Oxygen Dilution)燃烧和增氧燃烧相结合,以实现天然气燃烧过程中低CO_(2)和NO排放。基于0.58 MW工业炉,开展了空气预混增氧方式下天然气MILD燃烧及NO排放特性模拟研究,分析了氧气浓度(19.5%~30.0%)和氧化剂射流速度(100~300 m/s)对增氧MILD燃烧方式下炉内流场、温度和反应区分布及NO排放特性的影响。结果表明,在MILD燃烧器结构不变的条件下,当氧气浓度从19.5%增加到30.0%时,高温区更加集中,温度分布均匀性削弱,NO排放从32.4×10^(-6)增加至58.9×10^(-6),增加了82%,意味着高氧条件下MILD燃烧的低氮排放特性将会消失。然而,同氧气浓度条件下,提升氧化剂入口速度促进了烟气回流稀释,导致峰值温度下降,扩大了MILD燃烧反应区。当氧气浓度为26.5%时,将入口流速提升至150 m/s导致NO排放从49×10^(-6)降至31.2×10^(-6),可获得与空气工况下相当的NO排放水平。综上所述,空气直接预混增氧不利于MILD燃烧的形成,但通过提升氧化剂速度可实现高氧浓度条件下MILD燃烧并维持低NO排放。 展开更多
关键词 mild燃烧 增氧燃烧 氧气浓度 射流速度 NO排放
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Exploring cerebral structural and functional abnormalities in a mouse model of post-traumatic headache induced by mild traumatic brain injury 被引量:1
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作者 Dan Yang Bin-Bin Nie +6 位作者 Jin-Gang He Zong-Qiang Lv Feng-Feng Mo Si-Yi Ouyang Jie Wang Ju-Xiang Chen Tao Tao 《Zoological Research》 SCIE CSCD 2024年第3期648-662,共15页
Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability worldwide.Although PTH is often accompanied by neurological disorders,the exact... Mild traumatic brain injury(mTBI)-induced post-traumatic headache(PTH)is a pressing public health concern and leading cause of disability worldwide.Although PTH is often accompanied by neurological disorders,the exact underlying mechanism remains largely unknown.Identifying potential biomarkers may prompt the diagnosis and development of effective treatments for mTBI-induced PTH.In this study,a mouse model of mTBI-induced PTH was established to investigate its effects on cerebral structure and function during short-term recovery.Results indicated that mice with mTBI-induced PTH exhibited balance deficits during the early post-injury stage.Metabolic kinetics revealed that variations in neurotransmitters were most prominent in the cerebellum,temporal lobe/cortex,and hippocampal regions during the early stages of PTH.Additionally,variations in brain functional activities and connectivity were further detected in the early stage of PTH,particularly in the cerebellum and temporal cortex,suggesting that these regions play central roles in the mechanism underlying PTH.Moreover,our results suggested that GABA and glutamate may serve as potential diagnostic or prognostic biomarkers for PTH.Future studies should explore the specific neural circuits involved in the regulation of PTH by the cerebellum and temporal cortex,with these two regions potentially utilized as targets for non-invasive stimulation in future clinical treatment. 展开更多
关键词 Post-traumatic headache(PTH) mild traumatic brain injury(mTBI) Metabolic kinetics FMRI CEREBELLUM
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MILD燃烧研究进展及展望
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作者 周广钦 贾子秀 +2 位作者 李宇航 杜智华 张喜来 《节能》 2024年第9期122-124,共3页
中度与强化的低氧稀释(MILD)燃烧具有燃烧效率高、污染物生成水平低、燃烧稳定性高等优势。综述MILD燃烧判别标准、实验方法、燃料种类、工况条件等方面的研究进展,探究MILD燃烧与煤改气、富氧燃烧、预热燃烧、氨燃烧等工艺的耦合应用... 中度与强化的低氧稀释(MILD)燃烧具有燃烧效率高、污染物生成水平低、燃烧稳定性高等优势。综述MILD燃烧判别标准、实验方法、燃料种类、工况条件等方面的研究进展,探究MILD燃烧与煤改气、富氧燃烧、预热燃烧、氨燃烧等工艺的耦合应用现状。 展开更多
关键词 mild 燃料 燃烧特性 低NO_(x)排放
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Trends in the Application of Dyadic Coping in Older Adults with Mild Cognitive Impairment and Their Spouses
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作者 Yonghong Jiang Lin Wang +1 位作者 Lixia Peng Liling Wang 《Advances in Aging Research》 CAS 2024年第5期107-119,共13页
Dyadic coping plays an important role in older adults with mild cognitive impairment and their spouses. Significant correlations were found between dyadic coping and self-efficacy, anxiety and depression, marital qual... Dyadic coping plays an important role in older adults with mild cognitive impairment and their spouses. Significant correlations were found between dyadic coping and self-efficacy, anxiety and depression, marital quality, and quality of life in elderly patients with mild cognitive impairment and their spouses, and there were gender differences, with a 36.1% [P = 0.028, OR = 0.639, 95% CI (0.429, 0.952)] and 54% [P = 0.004, OR = 0.460, 95% CI (0.269, 0.785)] reduction in the risk of MCI and dementia for older men aged 65 - 69 years with a spouse and for those aged 80 years and older with a spouse, respectively. In contrast, there was no significant difference in the association between having or not having a spouse and developing MCI and dementia in older women (all P > 0.05). Psychosocial interventions, skills interventions, and exercise from the perspective of dyadic relationships were effective in improving the physical and mental health of older adults with mild cognitive impairment and their spouses. However, there is a lack of specific intervention programs for dyadic relationships in the local cultural context as an entry point. Therefore, it is necessary to draw on internal and external relevant literature to treat both partners as a whole for intervention, provide personalized social, cognitive and motor therapy for patients and promote the integration and participation of caregivers, help patients and spouses to improve the sense of well-being and intimacy, reduce the burden of caregivers, and build a dyadic coping intervention program suitable for elderly patients with mild cognitive impairment in China. The current article aims to provide a conceptual review focusing on dyadic coping care to inform the development of a dyadic intervention program suitable for older adults with mild cognitive impairment in China. This review outlines the theoretical concepts, assessment tools, current state of research, and intervention methods for mild cognitive impairment and dyadic coping. 展开更多
关键词 mild Cognitive Impairment Dyadic Coping Couples REVIEW
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Right heart modified myocardial performance index and ductus venosus spectrum parameters in pre-eclampsia fetuses for predicting adverse pregnancy outcomes
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作者 GAO Jing LI Hezhou +4 位作者 WANG Ming WU Juan WANG Xinxia LIU Yun ZHU Ziqi 《中国医学影像技术》 CSCD 北大核心 2024年第8期1146-1150,共5页
Objective To observe the values of changes of right heart modified myocardial performance index(Mod-MPI)and ductus venosus(DV)spectrum parameters in pre-eclampsia fetuses for predicting adverse pregnancy outcomes.Meth... Objective To observe the values of changes of right heart modified myocardial performance index(Mod-MPI)and ductus venosus(DV)spectrum parameters in pre-eclampsia fetuses for predicting adverse pregnancy outcomes.Methods Eighty-one pregnant women diagnosed as pre-eclampsia were prospectively enrolled and divided into severe pre-eclampsia(SPE)group(n=39)and mild pre-eclampsia(MPE)group(n=42),while 85 healthy pregnant women were taken as controls(control group).Fetal right heart function parameters,including right ventricular isovolumetric relaxation time(IRT),isovolumetric contraction time(ICT),ejection time(ET),total spent time(TST),Mod-MPI,tricuspid valve peak flow velocity ratio in early and late diastole(TV-E/A),as well as blood flow velocities in each waveform of DV spectrum(S,V,D,and A wave)were obtained,and the pulsatility index(PI)and the ratio of blood flow velocities in each waveform of the DV(S/V,S/D,S/A,V/D,V/A,D/A)were calculated.Intrauterine fetal distress,preterm delivery,neonatal asphyxia and newborn with low weight were considered as adverse pregnancy outcomes.The correlations of right heart Mod-MPI and TV-E/A with DV parameters in pre-eclampsia fetuses were assessed,and their predictive efficacies for adverse pregnancy outcomes were evaluated for right heart Mod-MPI and DV using the receiver operating characteristics(ROC)and the area under the curves(AUC).Results Compared with control group and MPE group,fetal right heart IRT,ICT and Mod-MPI increased and ET decreased in SPE group(all P<0.05).No significant differences of right heart TST and TV-E/A among 3 groups(both P>0.05).Fetal DV A-wave velocity and V/D values progressively decreased but PI progressively increased in control,MPE and SPE groups(all P<0.05).Fetal right heart Mod-MPI in pre-eclampsia was moderately positively correlated with DV PI(r=0.637,P=0.016),while TV-E/A was weakly negatively correlated with DV V/D(r=-0.355,P=0.043).Adverse pregnancy outcomes were noticed in 59 pre-eclampsia cases.The AUC of fetal right heart Mod-MPI and DV PI for predicting adverse pregnancy outcomes in pre-eclampsia cases was 0.897 and 0.848,respectively,without significant difference(Z=0.460,P=0.400).Conclusion Changes of right heart Mod-MPI and DV spectrum parameters in pre-eclampsia fetuses had high value for predicting adverse pregnancy outcomes. 展开更多
关键词 pre-eclampsia fetal heart ventricular function ultrasonography prenatal prospective studies
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Innovative pathways allow safe discharge of mild acute pancreatitis from the emergency room
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作者 Darshan J Kothari Sunil G Sheth 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1475-1479,共5页
Acute pancreatitis(AP)is a leading cause of gastrointestinal-related hospitalizations in the United States,resulting in 300000 admissions per year with an estimated cost of over$2.6 billion annually.The severity of AP... Acute pancreatitis(AP)is a leading cause of gastrointestinal-related hospitalizations in the United States,resulting in 300000 admissions per year with an estimated cost of over$2.6 billion annually.The severity of AP is determined by the presence of pancreatic complications and end-organ damage.While moderate/severe pancreatitis can be associated with significant morbidity and mortality,the majority of patients have a mild presentation with an uncomplicated course and mortality rate of less than 2%.Despite favorable outcomes,the majority of mild AP patients are admitted,contributing to healthcare cost and burden.In this Editorial we review the performance of an emergency department(ED)pathway for patients with mild AP at a tertiary care center with the goal of reducing hospitalizations,resource utilization,and costs after several years of implementation of the pathway.We discuss the clinical course and outcomes of mild AP patients enrolled in the pathway who were successfully discharged from the ED compared to those who were admitted to the hospital,and identify predictors of successful ED discharge to select patients who can potentially be triaged to the pathway.We conclude that by implementing innovative clinical pathways which are established and reproducible,selected AP patients can be safely discharged from the ED,reducing hospitalizations and healthcare costs,without compromising clinical outcomes.We also identify a subset of patients most likely to succeed in this pathway. 展开更多
关键词 Emergency department mild pancreatitis PATHWAYS HOSPITALIZATION PREDICTORS
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High Areal Capacity and Long Cycle Life Flexible Mild Quasi-Solid-State Ag-Zn Battery with Dendrite-Free Anode
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作者 Yanzhe Zhu Renbo Zhu +10 位作者 Fandi Chen Shuo Zhang Yu-Chieh Kuo Peiyuan Guan Mengyao Li Yunjian Liu Zhaojun Han Tao Wan Dawei Wang Caiyun Wang Dewei Chu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期34-41,共8页
Silver-zinc(Ag-Zn)batteries are a promising battery system for flexible electronics owing to their high safety,high energy density,and stable output voltage.However,poor cycling performance,low areal capacity,and infe... Silver-zinc(Ag-Zn)batteries are a promising battery system for flexible electronics owing to their high safety,high energy density,and stable output voltage.However,poor cycling performance,low areal capacity,and inferior flexibility limit the practical application of Ag-Zn batteries.Herein,we develop a flexible quasi-solid-state Ag-Zn battery system with superior performance by using mild electrolyte and binder-free electrodes.Copper foam current collector is introduced to impede the growth of Zn dendrite,and the structure of Ag cathode is engineered by electrodeposition and chloridization process to improve the areal capacity.This novel battery demonstrates a remarkable cycle retention of 90%for 200 cycles at 3 mA cm^(-2).More importantly,this binder-free battery can afford a high capacity of 3.5 mAh cm^(-2)at 3 mA cm^(-2),an outstanding power density of 2.42 mW cm^(-2),and a maximum energy density of 3.4 mWh cm^(-2).An energy management circuit is adopted to boost the output voltage of a single battery,which can power electronic ink display and Bluetooth temperature and humidity sensor.The developed battery can even operate under the extreme conditions,such as being bent and sealed in solid ice.This work offers a path for designing electrodes and electrolyte toward high-performance flexible Ag-Zn batteries. 展开更多
关键词 binder-free electrodes dendrite-free flexible Ag-Zn battery mild electrolyte quasi-solid-state
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Mild polarization electric field in ultra-thin BN-Fe-graphene sandwich structure for efficient nitrogen reduction
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作者 Ziyuan Xiu Wei Mu +1 位作者 Xin Zhou Xiaojun Han 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期126-137,共12页
The electrocatalytic N_(2)reduction reaction(NRR)is expected to supersede the traditional Haber-Bosch technology for NH3 production under ambient conditions.The activity and selectivity of electrochemical NRR are rest... The electrocatalytic N_(2)reduction reaction(NRR)is expected to supersede the traditional Haber-Bosch technology for NH3 production under ambient conditions.The activity and selectivity of electrochemical NRR are restricted to a strong polarized electric field induced by the catalyst,correct electron transfer direction,and electron tunneling distance between bare electrode and active sites.By coupling the chemical vapor deposition method with the poly(methyl methacylate)-transfer method,an ultrathin sandwich catalyst,i.e.,Fe atoms(polarized electric field layer)sandwiched between ultrathin(within electron tunneling distance)BN(catalyst layer)and graphene film(conducting layer),is fabricated for electrocatalytic NRR.The sandwich catalyst not only controls the transfer of electrons to the BN surface in the correct direction under applied voltage but also suppresses hydrogen evolution reaction by constructing a neutral polarization electric field without metal exposure.The sandwich electrocatalyst NRR system achieve NH3 yield of 8.9μg h^(−1)cm^(−2)and Faradaic Efficiency of 21.7%.The N_(2)adsorption,activation,and polarization electric field changes of three sandwich catalysts(BN-Fe-G,BN-Fe-BN,and G-Fe-G)during the electrocatalytic NRR are investigated by experiments and density functional theory simulations.Driven by applied voltage,the neutral polarized electric field induced by BN-Fe-G leads to the high activity of electrocatalytic NRR. 展开更多
关键词 Ultra-thin BN Fe doping BN-Fe-graphene mild polarization electric field Nitrogen reduction reaction
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The Effects of Mindfulness-Based Interventions on Symptoms of Mild Traumatic Brain Injury:A Systematic Review
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作者 Qiqi Feng Zhijian Huang +1 位作者 Yanqiu Wang Bin Wang 《International Journal of Mental Health Promotion》 2024年第6期417-428,共12页
Mindfulness-based interventions(MBIs)are emerging non-pharmacological treatments for mild traumatic brain injury(mTBI).In this systematic review,the authors aimed to evaluate the potential efficacy of MBIs to provide ... Mindfulness-based interventions(MBIs)are emerging non-pharmacological treatments for mild traumatic brain injury(mTBI).In this systematic review,the authors aimed to evaluate the potential efficacy of MBIs to provide recommendations for treating patients with mTBI.We searched of the English literature on MBIs for patients with mTBI as of 01 September,2023,using the PubMed,Web of Science,PsycINFO,and Scopus databases.One author performed data extraction and quality scoring of the included literature according to the proposed protocol,and another conducted the review.The review was not registered.A total of 11 studies met the final inclusion criteria,5 of which involved military personnel(veterans).MBIs covered in this review include goal-oriented attention self-regulation(GOALS),mindfulness-based stress reduction(MBSR),acceptance and commitment therapy(ACT),and so on.Research shows that MBSR mainly reduces mental fatigue symptoms in mTBI patients,and GOALS tend to improve their cognitive function.The effect of MBIs on psychological symptoms needs further exploration.Other studies,such as mindfulness-based group therapy and intervention studies targeting mTBI military personnel,are relatively sparse.MBIs have specific effects on mental fatigue and cognitive dysfunction in patients with mTBI.However,the effect on psychological distress and the sustained effectiveness across all symptoms still need further exploration.Considering the particularity of military personnel suffering from mTBI,researchers need to do more intervention studies targeting mTBI military personnel.Therefore,the design of future MBIs trials for mTBI patients’needs to take into account all the factors,such as different populations and severity of traumatic brain injury,to verify the effectiveness of MBIs in alleviating mTBI symptoms and explore the mechanism of intervention. 展开更多
关键词 MINDFULNESS traumatic brain injury mild
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Enhancing Mild Cognitive Impairment Detection through Efficient Magnetic Resonance Image Analysis
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作者 Atif Mehmood Zhonglong Zheng +7 位作者 Rizwan Khan Ahmad Al Smadi Farah Shahid Shahid Iqbal Mutasem K.Alsmadi Yazeed Yasin Ghadi Syed Aziz Shah Mostafa M.Ibrahim 《Computers, Materials & Continua》 SCIE EI 2024年第8期2081-2098,共18页
Neuroimaging has emerged over the last few decades as a crucial tool in diagnosing Alzheimer’s disease(AD).Mild cognitive impairment(MCI)is a condition that falls between the spectrum of normal cognitive function and... Neuroimaging has emerged over the last few decades as a crucial tool in diagnosing Alzheimer’s disease(AD).Mild cognitive impairment(MCI)is a condition that falls between the spectrum of normal cognitive function and AD.However,previous studies have mainly used handcrafted features to classify MCI,AD,and normal control(NC)individuals.This paper focuses on using gray matter(GM)scans obtained through magnetic resonance imaging(MRI)for the diagnosis of individuals with MCI,AD,and NC.To improve classification performance,we developed two transfer learning strategies with data augmentation(i.e.,shear range,rotation,zoom range,channel shift).The first approach is a deep Siamese network(DSN),and the second approach involves using a cross-domain strategy with customized VGG-16.We performed experiments on the Alzheimer’s Disease Neuroimaging Initiative(ADNI)dataset to evaluate the performance of our proposed models.Our experimental results demonstrate superior performance in classifying the three binary classification tasks:NC vs.AD,NC vs.MCI,and MCI vs.AD.Specifically,we achieved a classification accuracy of 97.68%,94.25%,and 92.18%for the three cases,respectively.Our study proposes two transfer learning strategies with data augmentation to accurately diagnose MCI,AD,and normal control individuals using GM scans.Our findings provide promising results for future research and clinical applications in the early detection and diagnosis of AD. 展开更多
关键词 Alzheimer’s disease mild cognitive impairment normal control transfer learning CLASSIFICATION augmentation
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Prevalence and Demographic Distributions of Pre-Eclampsia among Pregnant Women at Ho Teaching Hospital
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作者 Adwoa Nyarko Joshua A. Kunfah +3 位作者 David Z. Kolbilla Collins Adombire Akayuure Jamilatu B. Kappiah Sylvanus Kampo 《Open Journal of Obstetrics and Gynecology》 2024年第4期621-636,共16页
Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevale... Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevalence and associated risk factors are still significant, especially in developing countries including Ghana. This study aimed to assess the prevalence and demographic distributions associated with pre-eclampsia among pregnant women at the Ho Teaching Hospital. Methods: A facility-based retrospective study was conducted by reviewing available data or hospital records of pregnant mothers admitted to the labor and maternity wards from January 2018 to December 2020. All pregnant women who were diagnosed with pre-eclampsia within this period were included in the study. The data were collected using a structured checklist. Results: 5609 data on pregnant women from 2018 to 2020 were recorded. Out of the 5609 data recorded, 314 pre-eclampsia cases were recorded giving an overall prevalence of 5.6%. The yearly prevalence for 2018, 2019, and 2020 were 4.6%, 5.6%, and 6.6%, respectively. The most recorded pre-eclampsia cases were seen among women within the age group of 18 - 24 years. The data showed that 112 (35.7%) of the pregnant women who had pre-eclampsia were nulliparous. Pre-eclampsia-associated maternal and fetal complications were;preterm delivery 221 (70.4%), intrauterine fetal death 62 (19.7%), eclampsia 9 (2.9%), HELLP syndrome 5 (1.6%) and maternal death 17 (5.4%). Associated factors of pre-eclampsia were parity, level of education, and occupation (p ≤ 0.05). Conclusion: The findings of this study showed a rising trend in the incidence of pre-eclampsia over the years at the Ho Teaching Hospital. Parity, level of education, and occupation were found to be associated with developing pre-eclampsia. 展开更多
关键词 pre-eclampsia PREVALENCE Demographic Distributions Risk Factors ANTENATAL MATERNAL
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Predictive Factors for Pre-Eclampsia: A Case-Control Study in Two Hospitals in Yaounde
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作者 Junie Annick Metogo Ntsama Ines Winnie Gouanfo +5 位作者 Claude Hector Mbia Wilfried Loic Tatsipie Pascal Mpono Madye Ngo Dingom Felix Essiben Claude Cyrille Noa Ndoua 《Open Journal of Obstetrics and Gynecology》 2024年第4期565-574,共10页
Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-... Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-eclampsia in two hospitals in the city of Yaoundé. Methods: A case-control study was conducted at the Gynaecology & Obstetrics department of the Yaoundé Gynaeco-Obstetric and Paediatric Hospital (YGOPH) and the Main Maternity of the Yaoundé Central Hospital (MM-YCH) from February 1 to July 30, 2022. The cases were all pregnant women presenting with pre-eclampsia. The control group included pregnant women without pre-eclampsia. Descriptive statistics followed by logistic regression analyses were conducted with level of significance set at p-value Results: Included in the study were 33 cases and 132 controls, giving a total of 165 participants. The predictive factors for pre-eclampsia after multivariate analysis were: primiparity (aOR = 51.86, 95% CI: 3.01 - 1230.96, p = 0.045), duration of exposure to partner’s sperm Conclusion: The odds of pre-eclampsia increased with primiparity, duration of exposure to partner’s sperm < 3 months, personal history of pre-eclampsia and maternal history of pre-eclampsia. Recognition of these predictor factors would improve the ability to diagnose and monitor women likely to develop pre-eclampsia before the onset of disease for timely interventions. 展开更多
关键词 pre-eclampsia Predictive Factors Yaoundé
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Antidepressant effects of Yuanzhi (Polygalae Radix) extract on chronic unpredictable mild stress-induced depression in rats: modulation of the NLRP3 inflammasome and NF-κB pathway
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作者 CHEN Yuzhen ZHAO Yongzhi +4 位作者 ZHANG Yiwen CHEN Fang Iqbal Choudhary Muhammad LIU Xinmin JIANG Ning 《Digital Chinese Medicine》 CAS CSCD 2024年第2期184-194,共11页
Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total ... Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total of 40 male Sprague Dawley(SD)rats were randomly divided into control;model;low dose of PR(PR-L;0.5 g/kg);high dose of PR(PR-H;1 g/kg);and fluoxetine(10 mg/kg)groups;with 8 rats in each group.Except for the rats in control group;those in the other four groups underwent CUMS-induced depression modeling.PR and fluoxetine were administered intragastrically once daily;30 min prior to the CUMS procedure;for 14 consecu-tive days until the behavioral tests were performed.After CUMS modeling;the sucrose prefer-ence test(SPT);open field test(OFT);novelty-suppressed feeding test(NSFT);forced swim test(FST);and tail suspension test(TST)were employed to assess the pharmacological ef-fects of PR on the mitigation of depressive-like behaviors in rat models.Additionally;the en-zyme-linked immunosorbent assay(ELISA)was utilized to quantify the serum levels of tumor necrosis factor(TNF)-α;interleukin(IL)-6;and IL-1βin the rats.Western blot analysis was al-so conducted to evaluate the protein expression levels of nuclear factor kappa-B(NF-κB);in-ducible nitric oxide synthase(iNOS);cyclooxygenase-2(COX-2);nucleotide-binding oligomerization domain(NOD)-like receptor family pyrin domain containing 3(NLRP3);apoptosis-associated speck-like protein containing caspase recruitment domain(ASC);and caspase-1 in the hippocampal tissues of the rats.Immunofluorescence staining was per-formed to observe the morphological changes in ionized calcium-binding adapter molecule 1 positive(Iba-1+)cells in the dentate gyrus(DG)of rats with CUMS-induced depression.Results(i)Treatment with PR-H and fluoxetine resulted in significant enhancements in both the total distance and time the rats moved during tests(P<0.01 and P<0.05;respectively).Post-administration of PR-H and fluoxetine also led to statistically significant increase in su-crose preference among rats(P<0.05).Besides;PR-L;PR-H;and fluoxetine treatment markedly decreased the latency of ingestion(P<0.05;P<0.05;and P<0.01;respectively).As observed from the FST;PR-L;PR-H;and fluoxetine presented antidepressant effects on rats with CUMS-induced depression;leading to the reduction in time of their immobility(P<0.05;P<0.01;and P<0.01;respectively).The results of TST indicated reduced immobility time in rats receiving PR-H and fluoxetine treatment as well(P<0.01).(ii)Rats in model group showed an increase in the levels of Iba-1+microglia in their left and right brains in compari-son with control group(P<0.01).However;such increase was negated post PR treatment(P<0.01).Treatment with PR-L;PR-H;and fluoxetine considerably reduced the levels of inflam-matory factors(TNF-α;IL-1β;and IL-6;P<0.01).In addition;treatment of PR-L and PR-H ef-fectively counteracted the elevated levels of NLRP3;ASC;and caspase-1;and markedly down-regulated the expression levels of phosphorylated p65(p-p65);COX-2;and iNOS in rats’hip-pocampus(P<0.01).Conclusion Collectively;these findings indicate that PR exerts an antidepressant effect on rats with CUMS-induced depression partially through the modulation of the NLRP3 and NF-κB signaling pathways. 展开更多
关键词 DEPRESSION Yuanzhi(Polygalae Radix) Chronic unpredictable mild stress(CUMS) Proinflammatory cytokine Neuroinflammatory
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Activated Protein C Resistance in Patients with Pre-Eclampsia in Lagos, Nigeria
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作者 Nosimot O. Davies Titilope A. Adeyemo +2 位作者 Sunday I. Omisakin Akaninyene A. Udousoro Kabiru A. Rabiu 《Open Journal of Obstetrics and Gynecology》 2024年第4期575-590,共16页
Background: Preeclampsia is reported to complicate 2% - 8% of pregnancies globally and is an important cause of maternal and perinatal morbidity and mortality. The aetiology and pathogenesis are still poorly understoo... Background: Preeclampsia is reported to complicate 2% - 8% of pregnancies globally and is an important cause of maternal and perinatal morbidity and mortality. The aetiology and pathogenesis are still poorly understood and substantial improvement has not been made in the prediction, prevention and treatment of the disease. Objective: To compare the frequency of activated protein C resistance (APC-R) in patients with pre-eclampsia to that of normotensive pregnant women and to determine the correlation between activated protein ratio (APC-ratio) and the severity of pre-eclampsia. Methodology: A cross-sectional study was carried out in 100 pre-eclamptic patients and 100 normotensive pregnant controls. The APC-ratio was determined using the modified activated partial thromboplastin time. Study participants with APC-ratio of less than 2.0 were defined as having APC-R. Data was analyzed using SPSS version 22.0. Results: Mean APC-ratio was significantly lower in pre-eclamptics (2.89 ± 1.70) compared to normotensive pregnant women (3.57 ± 1.06) (p = 0.0008) and the levels were also higher in mild (2.95 ± 1.15) compared to severe pre-eclamptics (2.62 ± 1.14). The frequency of APC-R was 26% among women with pre-eclampsia compared to 4% among normotensive controls (p = 0.000). Among 100 pre-eclamptic women 7 (21.2%) out of 33 with mild pre–eclampsia had APC-R, while 19 (28.4%) out of 67 with severe pre-eclampsia had APC-R. APC-ratio had a significant negative correlation with mean arterial blood pressure (r = −0.324;p = 0.000) and proteinuria (r = −0.379;p = 0.000) among study participants. Conclusion: The frequency of activated protein c resistance is significantly higher in pre-eclamptics compared to normotensive pregnant women and this is more pronounced in those with severe pre-eclampsia compared with those with mild disease. APC-R may therefore be used as a marker of severity in the disease. 展开更多
关键词 Activated Protein C Resistance Activated Protein C Ratio pre-eclampsia
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Effect of Dendrobium nobile powder combined with conventional therapy on mild to moderate fatty liver
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作者 Xi Le Yin Zhang +5 位作者 Mei Yang Jie Li Hao Wang Jin-Lin Wu Juan Deng Hong-Min Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第45期4791-4800,共10页
BACKGROUND Nonalcoholic fatty liver disease(NAFLD)encompasses a variety of liver conditions impacting individuals who consume minimal or no alcohol.Recently,traditional Chinese medicine has been gradually used to trea... BACKGROUND Nonalcoholic fatty liver disease(NAFLD)encompasses a variety of liver conditions impacting individuals who consume minimal or no alcohol.Recently,traditional Chinese medicine has been gradually used to treat mild to moderate fatty liver,among which Dendrobium nobile Lindl.powder has been affirmed by many doctors and patients to be effective.However,there is limited research on combining this treatment with standard therapies for mild to moderate NAFLD.AIM To survey the effect of combining Dendrobium nobile Lindl.powder with standard treatment on liver function and lipid metabolism disorder in patients with mild to moderate NAFLD.METHODS Eighty patients with mild to moderate NAFLD participated in this retrospective study,classified into two groups:The observation group(n=40)and the control group(n=40).In November 2020 and November 2022,the study was conducted at People’s Hospital of Chongqing Liang Jiang New Area.The control group received standard treatment,while the observation group received Dendrobium nobile Lindl.powder based on the control group.The study compared differences in traditional Chinese medicine clinical syndrome scores,liver fibrosis treatment,liver function indicators,lipid levels,and serum inflammatory factor levels before and after treatment,and we calculated the incidence of adverse reactions for both groups.RESULTS The total effective rate was 97.50%in the observation group and 72.5%in the control group.After 8 weeks of treatment,the main and secondary symptom scores remarkably decreased,especially in the observation group(P<0.05),and there was a significant reduction in the serum levels of hyaluronic acid(HA),laminin(LN),human rocollagen III(PC III),and collagen type IV(CIV).The levels of HA,LN,PC III,and CIV were significantly lower in the observation group(P<0.05).After 8 weeks,both groups indicated remarkable improvements in liver function and blood lipid levels,with the observation group having even lower levels(P<0.05).Serum levels of interleukin-1β,tumor necrosis factor-α,and interleukin-8 also dropped significantly.The observation group had a lower rate of adverse reactions(5.00%)compared to the control group(22.50%).CONCLUSION Adding Dendrobium nobile Lindl.powder to standard treatment has been found to remarkably improve symptoms and reduce inflammation in patients with mild to moderate fatty liver disease.It also enhances hepatic function and lipid profile,ameliorates liver fibrosis indices,and lowers the risk of side effects.Consequently,this therapeutic protocol shows promise for clinical implementation and dissemination. 展开更多
关键词 Dendrobium nobile Lindl.powder Nonalcoholic fatty liver disease Combination treatment mild to moderate fatty liver Liver function Lipid metabolism disorder
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