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Investigation on the Knowledge, Attitude and Practice of Oral Health among Medical College and University Undergraduate
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作者 Xiuying Guan dongming li +4 位作者 Deping Zou Xin Yu Shuyin Pan Zheng Yang Jianzhong Huang 《Health》 2024年第7期602-614,共13页
Objectives: This study aims to investigate the status of knowledge, attitude and practice (KAP) of oral health among medical undergraduate students, and provide reference for implementing oral health interventions. Me... Objectives: This study aims to investigate the status of knowledge, attitude and practice (KAP) of oral health among medical undergraduate students, and provide reference for implementing oral health interventions. Methods: A total of 528 undergraduate students enrolled in Fuzhou Medical College from February 2023 to September 2023 were selected as the research subjects. Their oral health KAP were investigated, and the oral health behavior habits of different types of medical students were compared, and possible influencing factors were analyzed. Results: The total awareness rate of oral health knowledge among medical students is 77.0%, with an average score of 3.85 ± 1.16 points. The overall positive rate of oral health attitudes among medical students is 80.0%, with an average score of 3.19 ± 0.72 points. The total qualified rate of oral health behavior is 65.9%, with an average score of 4.61 ± 1.23 points. The scores of oral health knowledge, attitudes, and behaviors among medical students are related to gender, major, smoking status, and oral health status. The frequency of brushing teeth in the female group was higher than that in the male group, while the habit of brushing teeth before bedtime and the frequency of timely replacement of toothbrushes when deformed were lower, with statistical significance (p 0.05). The frequency of timely replacement of toothbrushes varies among medical students from different majors, and the difference is statistically significant (p 0.05). People who have a habit of eating hot and cold food have a higher frequency of brushing their teeth every day, and the difference is statistically significant (p 0.05). Non smokers have a better habit of brushing their teeth before bedtime and a higher frequency of timely replacement when their toothbrush deforms, with a statistically significant difference (p 0.05). The frequency of using fluoride toothpaste or medicated toothpaste, having a habit of unilateral chewing, and timely replacement of toothbrushes when deformed in patients with existing oral problems is higher than that of those without oral problems, and the difference is statistically significant (p 0.05). Conclusion: The knowledge, attitude, and behavior of oral health among medical students in this school are above average. Students with different genders, dietary and smoking habits, and oral health status have different oral health behavioral habits. It is recommended to include oral health education in mandatory courses for various medical majors. 展开更多
关键词 Medical Students Oral Health Knowledge Attitude Practice Correlation Analysis
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Effects of constant light and dark conditions on the locomotor activity,body mass,and body temperature rhythms of Eurasian Tree Sparrows(Passer montanus)
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作者 lirong Zuo Ibrahim MAhmad +3 位作者 Yuanyuan liu limin Wang Shu Fang dongming li 《Avian Research》 SCIE CSCD 2023年第3期435-442,共8页
Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior... Light is an essential environmental cue influencing the endogenous circadian clocks that regulate behavioral and physiological processes in animals.Despite extensive research on the circadian rhythms of avian behavior and physiology,the mechanisms by which they adapt and adjust to abnormal photoperiod conditions,such as artificial light,have yet to be fully elucidated.Here,the circadian rhythms of the body mass,activity,and core and peripheral body temperatures of the Eurasian Tree Sparrow(Passer montanus,ETS)-a diurnal passerine-were examined under three different lighting conditions:constant light(LL),constant darkness(DD),and normal light-dark cycles(LD).Our results showed that the activity,body mass,core,tarsometatarsus,and eye temperatures of the ETSs varied significantly with treatment,time,and the interaction between treatment and time;however,there was no significant change in body mass in response to the interaction between time and treatment.Under LD conditions,the ETSs exhibited significant circadian rhythms in activity and core,tarsometatarsus,and eye temperatures.Under LL conditions,only the core temperature exhibited significant rhythmicity.Under DD conditions,there were no significant circadian rhythms in activity,body mass,and eye temperature;however,the core and tarsometatarsus temperatures remained rhythmic.Our results indicate that the core body temperature rhythm of ETS is endogenous and can be maintained under abnormal photoperiods.In contrast,the activity and body surface temperature,uncoupled from the core body temperature under abnormal photoperiod conditions,strongly depend on light.These results differ from those of other diurnal avian species,suggesting a unique coping mechanism of ETS in response to an abnormal photoperiod. 展开更多
关键词 Eurasian Tree Sparrow ACTIVITY Body mass Body temperature Circadian rhythm
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Breath-by-breath measurement of exhaled ammonia by acetonemodifier positive photoionization ion mobility spectrometry via online dilution and purging sampling
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作者 Lu Wang Dandan Jiang +7 位作者 Lei Hua Chuang Chen dongming li Weiguo Wang Yiqian Xu Qimu Yang Haiyang li Song Leng 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期412-420,共9页
Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualita... Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH_(3)with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH_(3)product ion peak of(C_(3)H_(6)O)_(4)NH_(4)^(+)(K_(0)=1.45 cm^(2)/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C_(3)H_(6)O)_(2)H^(+)(K_(0)=1.87 cm^(2)/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH_(3)qualitative identification.Moreover,the interference of high humidity and the memory effect of NH_(3)molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92μmol/L with a response time of 40 ms was achieved,and the exhaled NH_(3)profile could be synchronized with the concentration curve of exhaled CO_(2).Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH_(3)of healthy subjects,demonstrating its great potential for clinical disease diagnosis. 展开更多
关键词 Photoionization ion mobility spectrometry Acetone modifier Exhaled ammonia Breath analysis
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Integration of the Historical Initiative Spirit into the Ideological and Political Course of Colleges and Universities : Value Implication, Main Contents and Practical Dimension
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作者 dongming li Ying WANG 《Asian Agricultural Research》 2023年第9期51-55,共5页
The value implication,main contents and practical dimension of integrating the historical initiative spirit into the ideological and political course of colleges and universities were studied.From the perspective of v... The value implication,main contents and practical dimension of integrating the historical initiative spirit into the ideological and political course of colleges and universities were studied.From the perspective of value implication,integrating the historical initiative spirit into the ideological and political course of colleges and universities is helpful to promoting the integrity and innovation of the ideological and political course in colleges and universities,deepening the historical cognition of students and building the cornerstone of students belief.From the perspective of main contents,teachers of ideological and political course should clarify the theoretical connotation of the historical initiative spirit,give a thorough exposition of the generation logic of the historical initiative spirit,and explain The Times value of the historical initiative spirit lively.From the perspective of practical dimension,it is necessary to give full play to the educational function of the historical initiative spirit by enriching the content of curriculum teaching,innovating the ways and methods of education and teaching,integrating theory and practice,and online and offline interaction. 展开更多
关键词 Historical initiative spirit Ideological and political course of colleges and universities Educational function
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基于数学建模思想提升大学生创新能力策略研究
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作者 李东明 郝冰月 《教育教学研究前沿》 2024年第3期57-59,共3页
随着社会的不断发展和变化,创新已经成为推动经济增长和社会进步的重要驱动力。数学建模作为一种重要的思维方法和工具,以其独特的逻辑性和实践性,在培养大学生创新能力方面发挥着不可替代的作用。如何将数学建模思想更好地运用在教学... 随着社会的不断发展和变化,创新已经成为推动经济增长和社会进步的重要驱动力。数学建模作为一种重要的思维方法和工具,以其独特的逻辑性和实践性,在培养大学生创新能力方面发挥着不可替代的作用。如何将数学建模思想更好地运用在教学过程中,提升学生的创新能力,是值得教育工作者深入探讨的重要课题。对此,通过阐述数学建模思想在大学生创新能力培养中的应用价值,进而分析基于数学建模思想提升大学生创新能力的策略,以期帮助大学生更好地适应未来社会的发展需求。 展开更多
关键词 数学建模思想 大学生 创新能力
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Effects of capture and captivity on plasma corticosterone and metabolite levels in breeding Eurasian Tree Sparrows 被引量:6
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作者 Mo li Weiwei Zhu +6 位作者 Yang Wang Yanfeng Sun Juyong li Xuelu liu Yuefeng Wu Xuebin Gao dongming li 《Avian Research》 CSCD 2019年第2期228-237,共10页
Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hy... Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hypothalamic– pituitary–adrenal axis. In free-living birds, although elevated plasma corticosterone (CORT) is an important adaptation regulating physiological and behavioral responses during the process of capture and captivity stress, little information is currently available on the effects of such stress on plasma metabolite levels. Methods: We examined the effects of immediate capture and 24-h captivity on body mass, body condition, plasma CORT, and metabolite levels including glucose (Glu), triglyceride (TG), total cholesterol (TC), uric acid (UA), in breeding Eurasian Tree Sparrows (Passer montanus). Results: CORT and Glu levels were increased significantly by the stress of capture, whereas TC and UA levels decreased. Body mass, body condition declined notably after 24 h in captivity, but CORT, Glu, and UA levels increased. Furthermore, male sparrows had lower TG levels after both capture and captivity than those of females. The relationships between plasma CORT and metabolite levels varied between sexes. Conclusions: Our results revealed that the metabolic status of Eurasian Tree Sparrows could be dramatically altered by capture and captivity. Monitoring the dynamic effects of both capture and captivity on plasma CORT, metabolite levels in a free-living bird contributes to a better understanding of the stress-induced pathways involved in sexdependent energy mobilization. 展开更多
关键词 CAPTURE STRESS CAPTIVITY STRESS CORTICOSTERONE Plasma metabolites FREE-LIVING birds
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The role of climate factors in geographic variation in body mass and wing length in a passerine bird 被引量:7
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作者 Yanfeng Sun Mo li +3 位作者 Gang Song Fumin Lei dongming li Yuefeng Wu 《Chinese Birds》 CSCD 2017年第1期3-11,共9页
Background: Geographic variation in body size is assumed to reflect adaptation to local environmental conditions. Although Bergmann's rule is usually sufficient to explain such variation in homeotherms, some excep... Background: Geographic variation in body size is assumed to reflect adaptation to local environmental conditions. Although Bergmann's rule is usually sufficient to explain such variation in homeotherms, some exceptions have been documented. The relationship between altitude, latitude and body size, has been well documented for some vertebrate taxa during the past decades. However, relatively little information is available on the effects of climate variables on body size in birds.Methods: We collected the data of 267 adult Eurasian Tree Sparrow(Passer montanus) specimens sampled at 48 localities in China's mainland, and further investigated the relationships between two response variables, body mass and wing length, as well as a suit of explanatory variables, i.e. altitude, latitude, mean annual temperature(MAT), annual precipitation(PRC), annual sunshine hours(SUN), average annual wind speed(WS), air pressure(AP) and relative humidity(RH).Results: Our study showed that(1) although the sexes did not differ significantly in body mass, males had longer wings than females;(2) body mass and wing length were positively correlated with altitude but not with latitude;(3) body mass and wing length were negatively correlated with AP and RH, but not significantly correlated with WS. Body mass was positively correlated with SUN and inversely correlated with MAT. Wing length was not correlated with MAT in either sex, but was positively correlated with SUN and negatively correlated with PRC in male sparrows;(4) variation in body mass could be best explained by AP and SUN, whereas variation in wing length could be explained by RH and AP in both sexes. In addition, variation in male sparrows can be explained by SUN, WS and PRC but not in females.Conclusions: Two different proxies of body size, body mass and wing length, correlated with same geographic factors and different climate factors. These differences may reflect selection for heat conservation in the case of body mass, and for efficient flight in the case of wing length. 展开更多
关键词 Body mass Wing length ALTITUDE LATITUDE Climate factor Eurasian Tree Sparrow
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Life-history dependent relationships between plasma alkaline phosphatase activity and body condition in male Eurasian Tree Sparrows 被引量:1
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作者 Yuliang Zhao lingjuan Gong +3 位作者 Baohua Zhao Xuebin Gao Yuefeng Wu dongming li 《Avian Research》 CSCD 2017年第3期163-167,共5页
Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences ... Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass(SCM), and hematocrit(Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase(ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or Hct.Methods: We determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows(Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the birds.Results: Our study showed that(1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage;(2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding stages.Conclusions: Our results suggest that plasma ALP activities in free-living birds can be used as one of the indicators o body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals. 展开更多
关键词 Alkaline phosphatase Size-corrected mass HEMATOCRIT Passer montanus Life history Trade-off
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A comparison of flight energetics and kinematics of migratory Brambling and residential Eurasian Tree Sparrow
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作者 Yang Wang Yuan Yin +6 位作者 Zhipeng Ren Chuan Jiang Yanfeng Sun Juyong li Ghulam Nabi Yuefeng Wu dongming li 《Avian Research》 CSCD 2020年第3期215-223,共9页
Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mech... Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mechanical power.Methods:We studied the differences in morphology,flight kinematics,and energy cost between two passerines with comparable size,a migrant(Fringilla montifringilla,Brambling,BRAM),and a resident(Passer montanus,Eurasian Tree Sparrow,TRSP).Results:The BRAM had longer wings,higher aspect ratio,lower wingbeat frequency,and stroke amplitude compared to the TRSP despite the two species had a comparable body mass.The BRAM had a significantly lower maximum speed,lower power at any specific speed,and thus lower flight energy cost in relative to the TRSP although the two species had a comparable maximum vertical speed and acceleration.Conclusions:Our results suggest that adaptation for migration may have led to reduced power output and maximum speed to increase energy efficiency for migratory flight while residents increase flight speed and speed range adapting to diverse habitats. 展开更多
关键词 Flight energy efficiency Flight kinematics Flight speed Maximum load-lifting capacity
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More than a simple egg:Underlying mechanisms of cold tolerance in avian embryos 被引量:1
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作者 Ibrahim M.Ahmad dongming li 《Avian Research》 SCIE CSCD 2023年第2期267-280,共14页
Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain lar... Avian embryos,which develop within eggs,exhibit remarkable tolerance to extremely low temperatures.Despite being a common trait among all birds,the mechanisms underlying this cold tolerance in avian embryos remain largely unknown.To gain a better understanding of this phenomenon and the coping mechanisms involved,we reviewed the literature on severe cold tolerance in embryos of both wild and domestic birds.We found that embryos of different bird orders exhibit tolerance to severe cold during their development.In response to cold stress,embryos slow down their heartbeat rates and metabolism.In severe cold temperatures,embryos can suspend these processes,entering a torpid-like state of cardiac arrest.To compensate for these developmental delays,embryos extend their regular incubation periods.Depending on their embryonic age,embryos of all bird species can tolerate acute severe cold regimes;only a few tolerate chronic severe cold regimes.We also discussed various extrinsic and intrinsic factors that affect the tolerance of bird embryos to low temperatures before and after incubation.Cold tolerance appears to be a heritable trait shared by wild and domestic embryos of all bird classes,regardless of egg size or development(altricial/precocial).Driven by environmental variability,cold tolerance in avian embryos is an optimal physiological and ecological strategy to mitigate the adverse effects of cold conditions on their development in response to fluctuating environmental temperatures. 展开更多
关键词 Acute cold tolerance Avian embryo Chronic cold tolerance Embryonic development Hatching success Incubation period
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同步推量调强放疗在局部晚期非小细胞肺癌中的应用 被引量:19
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作者 尤静 杨丹 +6 位作者 李东明 姜蕾蕾 余荣 于会明 徐博 王维虎 石安辉 《中国肺癌杂志》 CAS CSCD 北大核心 2019年第11期696-701,共6页
背景与目的局部晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的标准治疗方案为放疗联合化疗,但其生存仍不令人满意。随着调强放疗技术的发展,同步推量(simultaneous integrated boost,SIB)技术成为局部晚期NSCLC的研究方向。本... 背景与目的局部晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的标准治疗方案为放疗联合化疗,但其生存仍不令人满意。随着调强放疗技术的发展,同步推量(simultaneous integrated boost,SIB)技术成为局部晚期NSCLC的研究方向。本研究拟探讨局部晚期NSCLC采用SIB调强放疗技术的有效性和安全性。方法回顾性分析北京大学肿瘤医院2015年6月-2018年12月采用SIB技术进行放疗的局部晚期NSCLC患者资料,采用Kaplan-Meier方法进行统计分析,分析其疗效、生存及治疗相关毒性。结果研究纳入93例患者,中位随访时间34.23个月,3年生存率、无进展生存率、无局部区域复发生存率和无远处转移生存率分别为53.0%、37.0%、50.5%和50.5%。3级放射性食管炎发生率为5.4%,≥3级放射性肺炎发生率为2.2%。结论局部晚期NSCLC采用SIB调强放疗技术安全有效。 展开更多
关键词 肺肿瘤 同步推量 有效性
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利用CRISPR/Cas9敲除人源细胞系中LMNA基因的研究 被引量:2
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作者 刘恒 李东明 +9 位作者 朱兰玉 赖乐锦 闫婉云 陆玉双 韦伊 黄月琪 方媚 苏元港 杨芳 舒伟 《遗传》 CAS CSCD 北大核心 2019年第1期66-75,共10页
LMNA基因编码A型和C型核纤层蛋白,参与细胞核核膜的组织,影响基因组稳定性并对细胞分化产生影响。人类肿瘤中LMNA表达异常普遍存在,其突变造成多种核纤层蛋白病,如Emery-Dreifuss肌营养不良症(Emery-Dreifussmusculardystrophy,EDMD)、... LMNA基因编码A型和C型核纤层蛋白,参与细胞核核膜的组织,影响基因组稳定性并对细胞分化产生影响。人类肿瘤中LMNA表达异常普遍存在,其突变造成多种核纤层蛋白病,如Emery-Dreifuss肌营养不良症(Emery-Dreifussmusculardystrophy,EDMD)、扩张型心肌病(dilatedcardiomyopathy,DCM)和儿童早老症(Hutchinson-Glifordprogeriasyndrome,HGPS)等。为进一步研究LMNA在细胞内的功能,本研究利用CRISPR/Cas9技术对体外培养的293T与HepG2细胞株的LMNA基因进行编辑,获得两株LMNA基因敲除(LMNA KO)的稳定细胞系。与野生型相比,LMNAKO细胞系增殖能力相对减弱,凋亡增加。同时,细胞形态上也发生显著改变,核膜凹凸不平。本研究首次报道了LMNA KO永生细胞系构建和形态研究结果,为后续LMNA基因功能研究和致病突变体研究奠定基础。 展开更多
关键词 LMNA基因 CRISPR/Cas9 293T HEPG2 细胞形态
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Coping with extremes:lowered myocardial phosphofructokinase activities and glucose content but increased fatty acids content in highland Eurasian Tree Sparrows 被引量:3
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作者 Boyang Ding Yuliang Zhao +6 位作者 Yanfeng Sun Qian Zhang Mo li Ghulam Nabi Yuefeng Wu Chuan Jiang dongming li 《Avian Research》 SCIE CSCD 2021年第4期699-706,共8页
Background:Efficient and selective utilization of metabolic substrates is one of the key strategies in high-altitude animals to cope with hypoxia and hypothermia.Previous findings have shown that the energy substrate ... Background:Efficient and selective utilization of metabolic substrates is one of the key strategies in high-altitude animals to cope with hypoxia and hypothermia.Previous findings have shown that the energy substrate utilization of highland animals varies with evolutionary history and phylogeny.The heart is a proxy for the cardiopulmonary system,and the metabolic substrate utilization in the myocardium is also under the strong selective pressure of chronically hypoxic and hypothermic environments.However,little information is available on the physiological adjustments in relation to metabolic substrate utilization in the myocardium for coping with high-altitude environments.Methods:We compared the metabolic enzyme activities,including hexokinase(HK),phosphofructokinase(PFK),pyruvate kinase(PK),citrate synthase(CS),carnitine palmitoyl transferase 1(CPT-1),lactic dehydrogenase(LDH),and creatine kinase(CK),and metabolic substrate contents including glucose(Glu),triglyceride(TG),and free fatty acid(FFA)in the myocardium of a typical human commensal species,Eurasian Tree Sparrows(Passer montanus)between the Qinghai-Tibet Plateau(the QTP,3230 m)and low altitude population(Shijiazhuang,80 m),and between sexes.Results:Among the seven metabolic enzymes and three substrates investigated,we identified no significant differences in PK,CPT-1,HK,CS,LDH,and CK activities and TG content of the myocardium between high and low altitude populations.However,the QTP sparrows had significantly lower Glu content and PFK activities but higher FFA content relative to their lowland counterparts.In addition,male sparrows had higher myocardial HK and CS activities relative to females,independent of altitude.Conclusions:Our results showed that the QTP sparrows elevated fatty acid utilization rather than glucose preference in the myocardium relative to lowland counterpart,which contributes to uncovering both the physiological adjustments for adapting to the extreme conditions of the QTP,intraspecifically. 展开更多
关键词 Energy utilization Eurasian Tree Sparrow Metabolic enzyme Myocardium The Qinghai-Tibet Plateau
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Seasonal variations in gonad morphology and hypothalamic GnRH-I and GnIH in Eurasian Tree Sparrow,a multi-brooded passerine 被引量:1
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作者 limin Wang Ghulam Nabi +8 位作者 li Zhang Dan liu Mo li Juyong li Kaixin Shi Ibrahim M.Ahmad Yuefeng Wu John C.Wingfield dongming li 《Avian Research》 SCIE CSCD 2022年第3期369-378,共10页
The hypothalamic-pituitary-gonadal(HPG)axis ubiquitously regulates seasonal reproduction,following the rhythmicity of a suite of environmental cues.Birds display prominent seasonal variations in gonad size regulated b... The hypothalamic-pituitary-gonadal(HPG)axis ubiquitously regulates seasonal reproduction,following the rhythmicity of a suite of environmental cues.Birds display prominent seasonal variations in gonad size regulated by two hypothalamic peptides,gonadotropin-releasing hormone-1(GnRH-I)and gonadotropin-inhibiting hormone(GnIH).How multi-brooded avian species adjust GnRH-I and GnIH to regulate gonadal morphology seasonally remains largely unknown.Here,we studied the variations in the hypothalamic immunoreactivity(ir)of GnRH-I and GnIH,gonadal proliferation,and apoptosis in a typical multi-brooded species,the Eurasian Tree Sparrow(Passer montanus),across the pre-breeding(PB),first breeding(FB),second breeding(SB),pre-basic molt(PM),and wintering stages(WS).Our results showed that both sexes had higher preoptic area(POA)-GnRH-I-ir but lower paraventricular nucleus(PVN)-GnIH-ir neurons during the breeding stages(FB and SB)relative to other life-history stages,with no significant differences between two broods.The testes and ovaries were significantly larger during the breeding stages.Testicular volume increased during the two broods due to anincreased diameter of seminiferous tubules.Furthermore,there were more testicular apoptotic cells in PB and WS stages than in breeding stages,and in PB stage than in PM stage.Males had higher POA-GnRH-I expression than females during the breeding stages,but both sexes had comparable PVN-GnIH expression throughout the annual cycle.Both sexes of the sparrows may undergo a similar pattern of life-history stage-dependent variation in the hypothalamic GnRH-I,GnIH,and gonadal morphology,except that during breeding stages,males may display higher expression of POA-GnRH-I relative to females.The higher expression of POA-GnRH-I-ir in breeding male sparrows may be critical for male-dependent parental care. 展开更多
关键词 Eurasian Tree Sparrow Gonads HYPOTHALAMUS Reproduction Seasonality
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Birds and plastic pollution:recent advances 被引量:1
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作者 limin Wang Ghulam Nabi +4 位作者 liyun Yin Yanqin Wang Shuxin li Zhuang Hao dongming li 《Avian Research》 SCIE CSCD 2021年第4期591-599,共9页
Plastic waste and debris have caused substantial environmental pollution globally in the past decades,and they have been accumulated in hundreds of terrestrial and aquatic avian species.Birds are susceptible and vulne... Plastic waste and debris have caused substantial environmental pollution globally in the past decades,and they have been accumulated in hundreds of terrestrial and aquatic avian species.Birds are susceptible and vulnerable to external environments;therefore,they could be used to estimate the negative effects of environmental pollution.In this review,we summarize the effects of macroplastics,microplastics,and plastic-derived additives and plastic-absorbed chemicals on birds.First,macroplastics and microplastics accumulate in different tissues of various aquatic and terrestrial birds,suggesting that birds could suffer from the macroplastics and microplastics-associated contaminants in the aquatic and terrestrial environments.Second,the detrimental effects of macroplastics and microplastics,and their derived additives and absorbed chemicals on the individual survival,growth and development,reproductive output,and physiology,are summarized in different birds,as well as the known toxicological mechanisms of plastics in laboratory model mammals.Finally,we identify that human commensal birds,long-life-span birds,and model bird species could be utilized to different research objectives to evaluate plastic pollution burden and toxicological effects of chronic plastic exposure. 展开更多
关键词 BIRDS Microplastics pollution Plastics pollution Toxicological effects
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Rate-Energy Tradeoff for Wireless Simultaneous Information and Power Transfer in Full-Duplex and Half-Duplex Systems
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作者 Xiaoye Shi Jin Sun +2 位作者 dongming li Fei Ding Zhaowei Zhang 《Computers, Materials & Continua》 SCIE EI 2020年第11期1373-1384,共12页
In this paper,we study the rate-energy tradeoff for wireless simultaneous in-formation and power transfer in full-duplex and half-duplex scenarios.To this end,the weighting function of energy efficiency and transmissi... In this paper,we study the rate-energy tradeoff for wireless simultaneous in-formation and power transfer in full-duplex and half-duplex scenarios.To this end,the weighting function of energy efficiency and transmission rate,as rate-energy tradeoff metric is first introduced and the metric optimization problem is formulated.Applying Karush-Kuhn-Tucker(KKT)conditions for Lagrangian optimality and a series of mathematical approximations,the metric optimization problem can be simplified.The closed-form solution of the power ratio is obtained,building direct relationship between power ratio and the rate-energy tradeoff metric.By choosing power ratio,one can make the tradeoff between information rate and harvested power in a straightforward and efficient way.Using the method similar to the half duplex systems,the optimal power ratio can be obtained in the full duplex systems,so as to balance the information transmission rate and energy transmission efficiency.Simulation results validate that the information rate is non-increasing with harvested power in half-duplex systems and the tradeoff of information rate and harvested power can be simply made.In the full duplex systems,the power ratio solution of the rate-energy tradeoff metric optimization problem can be used as the approximate optimal solution of the optimization problem and the approximation error is negligible. 展开更多
关键词 Power transfer full duplex optimization problem
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A phylogeny of the Passerida(Aves: Passeriformes)based on mitochondrial 12S ribosomal RNA gene
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作者 lina Wu Yanfeng Sun +3 位作者 Juyong li Yaqing li Yuefeng Wu dongming li 《Chinese Birds》 CSCD 2015年第1期22-29,共8页
Background: Passerida is the largest avian radiation within the order Passeriformes. Current understanding of the high-level relationships within Passerida is based on DNA–DNA hybridizations; however, the phylogeneti... Background: Passerida is the largest avian radiation within the order Passeriformes. Current understanding of the high-level relationships within Passerida is based on DNA–DNA hybridizations; however, the phylogenetic relationships within this assemblage have been the subject of many debates.Methods: We analyzed the 12 S ribosomal RNA gene from 49 species of Passerida, representing 14 currently recognized families, to outline the phylogenetic relationships within this group.Results: Our results identified the monophyly of the three superfamilies in Passerida: Sylvioidea, Muscicapoidea and Passeroidea. However, current delimitation of some species is at variance with our phylogeny estimate. First, the Parus major, which had been placed as a distinct clade sister to Sylvioidea was identified as a member of the super family;second, the genus Regulus was united with the Sturnidae and nested in the Muscicapoidea clade instead of being a clade of Passerida.Conclusion: Our results were consistent with Johansson's study of the three superfamilies except for the al ocation of two families, Paridae and Regulidae. 展开更多
关键词 PHYLOGENY Passerida MITOCHONDRIAL 12S RIBOSOMAL RNA GENE
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An Investigation into the Design of Blended Teaching in the Basic German Classroom
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作者 dongming li 《Journal of Contemporary Educational Research》 2020年第9期16-20,共5页
The rapid development of information technology has constantly promoted innovation and pedagogical reform of educational practice models.Blended teaching provides an ever-innovative new way of thinking for the current... The rapid development of information technology has constantly promoted innovation and pedagogical reform of educational practice models.Blended teaching provides an ever-innovative new way of thinking for the current classroom teaching reform.Based on the definition of the concept of blended teaching and the study of the theories related to blended teaching,this paper describes the basic design of German classroom teaching in a blended curriculum. 展开更多
关键词 Blended learning Basic German Classroom design
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Coping with extremes:convergences of habitat use,territoriality,and diet in summer but divergences in winter between two sympatric snow finches on the Qinghai-Tibet Plateau 被引量:3
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作者 dongming li Jason E.DAVIS +4 位作者 Yanfeng SUN Gang WANG Ghulam NABI John C.WINGFIELD Fumin LEI 《Integrative Zoology》 SCIE CSCD 2020年第6期533-543,共11页
On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild animals.To date,limited information is available on behavioral and ec... On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild animals.To date,limited information is available on behavioral and ecological traits concerning niche differentiation among sympatric animals on the Qinghai-Tibet Plateau,especially during winter when the environments are most severe.Here,we studied the seasonal variations in habitat occurrence,territorial behavior,and diet in two sympatric snow finches(the white-rumped snow finch,Onychostruthus taczanowskii,WRSF;and the rufous-necked snow finch,Pyrgilauda ruficollis,RNSF)to determine convergence and divergence of ecological traits in such severe climatic conditions.Our results showed that:(i)WRSF occupied rural areas as a dominant species throughout the annual cycle while RNSF occupied the rural areas in summer and then shifted to human-occupied areas in winter and spring;(ii)WRSFs exhibited robust aggressive behavior and territoriality during winter relative to RNSFs;(iii)the diets of both species varied with the season but did not vary between species except that WRSF ate significantly more seeds but RNSF consumed more starchy material derived from human food waste during winter.Therefore,the separations in the spatial niche and territoriality between WRSF and RNSF,especially in winter,may contribute to alleviating the pressure of interspecific competition,and promoting the coexistence of the two sympatric snow finches in the extreme environments on the Qinghai-Tibet Plateau. 展开更多
关键词 DIET habitat use Qinghai-Tibet Plateau snow finch territorial behavior
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Study of LED array fill light based on parallel particle swarm optimization in greenhouse planting 被引量:2
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作者 Feifei He lihua Zeng +1 位作者 dongming li Zhenhui Ren 《Information Processing in Agriculture》 EI 2019年第1期73-80,共8页
Agricultural productivity is crucial to the economy.The output and quality of crops have a direct impact on people’s daily lives and a country’s food and clothing.Therefore,harvesting high-quality crops efficiently ... Agricultural productivity is crucial to the economy.The output and quality of crops have a direct impact on people’s daily lives and a country’s food and clothing.Therefore,harvesting high-quality crops efficiently and maximizing yield per unit area are the most important goals pursued by farmers.As an important parameter of plant growth,light intensity is one of the important factors that affects plant growth and development,morphological establishment and accumulation of functional chemical substances.When light intensity cannot meet the plant’s needs,the optimal light intensity or uneven light distribution will have a greater impact on plant growth and development.This paper aims to address the optimal plant light intensity problem.The paper presents an expert system technology database storing the empirical value of real-time light intensity values and compares it with a parallel particle swarm optimization algorithm to identify the optimal locations where LED lights need to be turned on and where drive circuit lit LED arrays need to be situated,to identify the number of LED fill lights and to solve light intensity optimization problems. 展开更多
关键词 Particle swarm optimization GREENHOUSE Fill light Expert system LED
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