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Circadian rhythms of feeding, oviposition, and emergence of the boll weevil （Coleoptera： Curculionidae）

Insect Science 2006年第6期13卷 461-467页

作者： ShOIL M. GREENBERG j. SCOTT ARMSTRONG MAMOUDOUSETAMOU ThOMAS W. SAPPINGTON RANDY j. COLEMAN TONG-XIAN LIU USDA-ARS-SARC-BIRU Texas A&M University Agricultural Experiment Station Weslaco Texas USDA-ARS-CICGRU Ames Iow USA

Circadian rhythm of feeding, oviposition, and emergence of boll weevil adults were determined at five different photophases （24, 14, 12, 10, and 0 hours） and a constant 27℃ temperature, 65% Rh in the laboratory. Squares from Petri dishes, where they were exposed to boll weevil females, were removed and examined for feeding and oviposition punctures every 4 hours during daylight （0700-1900 h） and every 12 h at night （1900-0700 h） over eight consecutive days. Cohorts of randomly selected egg-punctured squares were sampled from ovipositing females at 0700, 1100, 1500, and 1900 during 24 hours and under different photophase treatments, and maintained in Petri dishes at 27 ＋ I℃, 65% Rh. Dishes were observed twice daily （1900 and 0700 h） for adults emerging at day or night. Circadian rhythm of oviposition was not affected by the length of the photophase. The boll weevil has round-the-clock circadian rhythm of oviposition, with a daytime preference. We observed that 82.4%-86.0% of the boll weevil eggs were deposited between 0700 and 1900 h, and 14.0%-17.6% between 1900 and 0700 h during a 24-h period. Feeding of boll weevil females in photoperiods 24：0 h （complete light） and 0：24 h （complete darkness） did not significantly change between 0700-1900 h versus 1900-0700 h, while the d .ally cycle of light and darkness in other photoperiods significantly increased the feeding punctures from 0700-1900 compared with 1900-0700 h. The circadian rhythm of emergence depended significantly on the time of oviposition and the length of the photophase. Investigation of boll weevil circadian rhythm provides a better understanding of boll weevil ecology and reveals potential weak links for improving control technologies targeting their reproductive strategies.

关键词： Anthonomus grandis emergence circadian rhythm oviposition photophase

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Effect of low temperatures on BAX and BCL2 proteins in rats with spinal cord ischemia reperfusion injury

Effect of low temperatures on BAX and BCL2 proteins in rats ...

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第十一届全国免疫学学术大会

作者： Zhu Ping Zhao M.y. Li X.h. Fu Q. Zhou Z.f. huang C.f. Zhang X.s. huang h.l. Tan Y. Li j.x. Li j.n. huang S. Ashraf M. Lu C. Chen j.m. Zhuang j. Guo h.m. Department of Cardiovascular Surgery Guangdong General HospitalGuangdong Cardiovascular InstituteGuangdong Academy of Medical Sciences Department of Pediatrics The Third Xiangya HospitalCentral South University Department of Pharmacology UIC College of Medicine

Objectives: Surgery on the chest often requires blocking of the abdominal aorta. however, the associated spinal cord ischemia/reperfusion injury(SCII) can cause paraplegia in severe cases. Conducting heart operations at low temperatures as a means of protecting the central nervous system. We report our preliminary investigation of the neuroprotective effect of different temperatures on the rat spinal SCII model. Our Objective was to determine whether the protective effect is closely related to the inhibition of apoptosis in nerve cells to improve the SCII protection method. Methods: We evaluated changes in BAX and BCL2 expression levels after spinal cord ischemia/reperfusion injury(SCII) and hypothermia during operations in rats. Eighty rats were divided into four groups: Group A(N = 20, 18°C);GroupB(N = 20, 28°C);Group C(N = 20, room temperature);and Group D(N = 20, sham operation control). Spinal cord ischemia was induced for 90 min. hypothermia was induced 15 min before, and maintained during ischemia, followed by heating to normothermia for 30 min after reperfusion. Motor function of the lower limbs was evaluated according to the Tarlov score at 72 and 168 h. For each rat, spinal cord samples were taken at 6, 24, 72 h, and 1 week to evaluate the histopathological changes, neuronal apoptosis, and BAX and BCL2 expression levels. Reaults: Compared with normothermia, hypothermia significantly improved hind limb function;GroupB achieved a higher score than Group A. Group D showed no neurologic deficiency, while the other groups showed various degrees. Group C exhibited greater neuronal apoptosis, higher BAX expression, but lower BCL2 expression than the other groups. Compared with Group A, BAX was expressed less and BCL2 more in GroupB, and there was less apoptosis in GroupB. Conclusion: hypothermia preserves hind limb motor function and reduces neuronal death, thereby protecting rats from SCII. The spinal cord may be protected from SCII by inhibition of BAX and acti

关键词： hypothermia Spinal cord ischemia/reperfusion injury BAX BCL2

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应用能量型超声检查显示并量化胎儿肺灌注情况(德国)

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世界核心医学期刊文摘（妇产科学分册） 2005年第10期1卷 59-60页

作者： jrn h FuchsB RathW 柳蕴 Schlossparkstraβ e 11a 52072 Aachen Germany.Dr

Purpose: Can information be obtained about the effectiveness of a medication for foetal lung maturation in cases of premature labour or the development of lung hypoplasia in cases of severe oligohydramnios using power- Doppler quantification of central and peripheral foetal lung perfusion? Methods: We examined the perfusion of the right lung at the level of the four- chamber view of 23 foetuses undergoing lung maturation therapy (day 0 and 3; 12 mg betamethasone day 1 and 2), 12 foetuses with severe oligohydramnios (largest pocket h normal amounts of amniotic fluid using powerDoppler. Picture sequences were stored during foetal immobility for at least 20 seconds (frame rate 6 hz). Data analysis was performed using a 8 bit procedure. Colour pixels were counted for every frame and separated for the central and peripheral parts of the foetal lung perfusion. The frequencies of colour pixels were arranged into 16 groups depending on a given scale of different colours ranging from dark red representing small amounts of blood to light yellow representing large amounts of blood. We calculated 3D- diagrams, “ colour range” (colour pixels/grey pixels) and a weighted mean (colour pixel × hue/16 hues). Results: Foetal lung perfusion is significantly increased in the central part of the lung compared to the peripheral part. There was no change of lung perfusion after a medication for foetal lung maturation. Cases complicated by severe oligohydramnios showed an over- all decrease of blood flow peripherally and the appearance of larger amounts of blood (shunts) as compared to foetuses with normal amounts of amniotic fluid. Conclusions: The development of foetal lung hypoplasia is associated with a decrease of lung perfusion as well as the appearance of larger amounts of blood in the peripheral parts of the lung. This phenomenon can be detected early in pregnancy by a quantification of colour pixels using power- Doppler ultrasound.

关键词：肺灌注超声检查羊水过少多普勒技术血液分流图像数据处理羊水暗区羊水量图像序列药物治疗疗效

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电热原子化和原子吸收法测定血中微量镉

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原子光谱分析 1981年第6期 14-17页

作者： h.T.Delves j.Woodward Unit of Chemical Pathology and human Metabo1ism University of Southampton Southampton S09 4XY United Kingdom Peikin-Elmer Ltd.Beaconsfield Buckinghamshire hP9 1QA

利用电热原子化和原子吸收测定微升体积全血样品中Cd含量的一种简单方法是把磷酸铵基体改进剂和在氧气氛下进行灰化结合起来。此方法的检出限是0.15μg/l,浓度为1.6μg/l时的精度是0.034(RSD)。加入到血样中的Cd含量为4μg/l、10μg/l时... 详细信息

利用电热原子化和原子吸收测定微升体积全血样品中Cd含量的一种简单方法是把磷酸铵基体改进剂和在氧气氛下进行灰化结合起来。此方法的检出限是0.15μg/l,浓度为1.6μg/l时的精度是0.034(RSD)。加入到血样中的Cd含量为4μg/l、10μg/l时,回收率的/平均值分别是98.8％和100.2％。当含Cd量的浓度范围为0.2-11.6μg/l时,用这种方法分析血样所得到的结果与微量进样火焰原子吸收法以及实验室间其他对照方法所获得的结果很一致。

关键词：原子化 Cd 血样基体改进剂灰化电热原子化器灰化温度原子吸收全血样品分子吸收

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Fabrication of all-transparent polymer-based and encapsulated nanofluidic devices using nano-indentation lithography

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Microsystems & Nanoengineering 2017年第1期3卷 373-381页

作者： Cong Wu Tiffany G.Lin Zhikun Zhan Yi Li Steve C.h.Tung William C.Tang Wen j.Li Department of Mechanical and Biomedical Engineering City University of Hong KongHong Kong 999077China Department of Biomedical Engineering University of CaliforniaIrvineCA 92697-2715USA Department of Automation Yanshan UniversityQinghuangdao 066004China Department of Mechanical Engineering University of ArkansasFayettevilleAR 72701USA

In this paper,we describe a novel and simple process for the fabrication of all-transparent and encapsulated polymeric nanofluidic devices using nano-indentation ***,a nanomechanical probe is used to‘scratch’nanoscale channels on polymethylmethacrylate(PMMA)substrates with sufficiently high ***,polydimethylsiloxane(PDMS)is used twice to duplicate the nanochannels onto PDMS substrates from the‘nano-scratched’PMMA substrates.A number of experiments are conducted to explore the relationships between the nano-indentation parameters and the nanochannel dimensions and to control the aspect ratio of the fabricated *** addition,traditional photolithography combined with soft lithography is employed to fabricate microchannels on another PDMS‘cap’*** manually aligning the substrates,all uncovered channels on two separate PDMS substrates are bonded to achieve a sealed and transparent nanofluidic device,which makes the dimensional transition from microscale to nanoscale *** smallest dimensions of the achievable nanochannels that we have demonstrated thus far are of~20 nm depth and~800 nm width,with lengths extendable beyond 100μ*** flow experiments are performed to verify the reliability of the *** types of colloidal solution are used to visualize the fluid flow through the nanochannels,that is,ethanol is mixed with gold colloid or fluorescent dye(fluorescein isothiocyanate),and the flow rate and filling time of liquid in the nanochannels are estimated based on time-lapsed image *** simplicity of the fabrication process,bio-compatibility of the polymer substrates,and optical transparency of the nanochannels for flow visualization are key characteristics of this approach that will be very useful for nanofluidic and biomolecular research applications in the future.

关键词： indentation lithography nanochannel nanofluidic device nanofluidic flow

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在流动粒子炉中的气体渗碳和中性淬火

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热处理技术与装备 1985年第3期 43-47页

作者： j.Virta h.Kleemola 李明湘潭风动机械厂

已经研究了在流动粒子炉巾工具钢的中性淬火和渗碳钢的气体渗碳。表1是这些钢的成份和用于测定炉中碳势的薄钢片的成份。

关键词：气体渗碳碳势控制流动粒子炉渗碳钢渗层深度残余奥氏体炉床硬度分布曲线

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A multi-channel chemical sensor and its application in detecting hydrothermal vents

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Acta Oceanologica Sinica 2019年第9期38卷 128-134页

作者： Zhen Cai A j Mur Luis jiwan han Kui Wang huawei Qin Ying Ye Ocean College Zhejiang University Zhoushan 316021 China Environmental and Rural Sciences Institute of Biological Aberystwyth University Aberystwyth SY23 3DA UK Key Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration Hangzhou 310012 China Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China Institute of Mechanical Engineering Hangzhou Dianzi University Hangzhou 310018 China

There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. ph, Eh, CO3^2- and SO4^2- electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with ph, Eh, CO3^2- and h2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and h2S, matched by increasing voltages of ph and CO3^2- . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists.

关键词： chemical sensor multi-channel hydrothermal vents detection chemical anomalies SWIR

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表面分析用的离子散射能谱

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微纳电子技术 1976年第6期 48-51页

作者： h.h.Brongersma W.j.Schouten 和存平

固体的离子散射是一个复杂的过程。然而,当选定一种特定的实验条件时,描述这一过程则可大为简化。对于非热离子而言,de Broglie 波长λ小于表面内原子间的距离。例如,1千电子伏的 Ne+离子,λ是0.002埃,而晶格的特征距离则为几个埃的数... 详细信息

固体的离子散射是一个复杂的过程。然而,当选定一种特定的实验条件时,描述这一过程则可大为简化。对于非热离子而言,de Broglie 波长λ小于表面内原子间的距离。例如,1千电子伏的 Ne+离子,λ是0.002埃,而晶格的特征距离则为几个埃的数量级。由于有这么大的差别,因而与低能电子和光子散射不同,离子散射的许多性质可以用古典力学精确地加以描述。对于具有碰撞能为1千电子伏数量级的惰性气体离子,描述固体的离子散射则更简单。这些离子的中和几率很高。因为仅仅电离的粒子可用我们的分析器检知,所以,多次散射离子则不一定被检知。虽然在小散射角下有时观察到二

关键词：原子层表面分析能谱氧化铁磁性入射离子离子流散射角

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