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Flexible Graphene Devices with an Embedded Back-Gate

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Graphene 2013年第1期2卷 13-17页

作者： jasper van Veen Andres Castellanos- gomez Herre S. j. van der Zant Gary A. Steele Kavli Institute of Nanoscience Delft University of Technology Delft The Netherlands

We show the fabrication of flexible graphene devices with an embedded backgate. The resistance of these devices can be tuned by changing the strain through the bending of the substrate. These devices can be useful for applications requiring a flexible graphene-based field effect transistor in where the graphene channel is not covered (such as biological or chemical sensors and photo-detectors).

关键词： Graphene Device Flexible Electronics Back-Gate Strain Engineering

Impact of COVID-19 on presentation,management,and outcomes of acute care surgery for gallbladder disease and acute appendicitis

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World journal of Gastrointestinal Surgery 2021年第8期13卷 859-870页

作者： Orly Nadell Farber Giselle I gomez Ashley L Titan Andrea T Fisher Christopher j Puntasecca Veronica Toro Arana Arielle Kempinsky Clare E Wise Kovi E Bessoff Mary T Hawn james R Korndorffer jr joseph D Forrester Micaela M Esquivel Department of Surgery Stanford University School of MedicinePalo AltoCA 94305United States

BACKGROUND The ongoing coronavirus disease 2019(COVID-19)pandemic has significantly disrupted both elective and acute medical *** from the early months suggest that acute care patient populations deferred presenting to the emergency department(ED),portending more severe disease at the time of ***,care for this patient population trended towards initial non-operative *** To examine the presentation,management,and outcomes of patients who developed gallbladder disease or appendicitis during the *** A retrospective chart review of patients diagnosed with acute cholecystitis,symptomatic cholelithiasis,or appendicitis in two EDs affiliated with a single tertiary academic medical center in Northern California between March and june,2020 and in the same months of *** were selected through a research repository using international classification of diseases(ICD)-9 and ICD-10 *** both years,313 patients were identified with either type of gallbladder disease,while 361 patients were identified with acute *** primary outcome was overall incidence of *** outcomes included presentation,management,complications,and 30-d re-presentation *** between different variables were explored using Pearson’s r correlation *** were compared using the Welch’s t-Test,Chi-squared tests,and Fisher’s exact test as *** Patients with gallbladder disease and appendicitis both had more severe presentations in *** respect to gallbladder disease,more patients in the COVID-19 cohort presented with acute cholecystitis compared to the control cohort[50%(80)vs 35%(53);P=0.01].Patients also presented with more severe cholecystitis in 2020 as indicated by higher mean Tokyo Criteria Scores[mean(SD)1.39(0.56)vs 1.16(0.44);P=0.02].With respect to appendicitis,more patients were diagnosed with a perforated appendix at presentation in 2020[20%(36)vs 16%(29);P=0.0

关键词： COVID-19 Cholecystitis Biliary colic Appendicitis Acute care surgery

Changes in Human Hair Induced by UV- and Gamma Irradiation

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Advances in Bioscience and Biotechnology 2016年第1期7卷 19-27页

作者： Ervin Palma David gomez Eugene Galicia Viktor Stolc Yuri Griko Evergreen Valley College San Jose CA USA Carnegie Melon University Moffett Field CA USA Division of Space Biosciences NASA Ames Research Center Moffett Field CA USA

The effect of UV- and 137Cs gamma radiation on the structural and chemical integrity of human hair was studied to determine the feasibility of using human hair as a non-invasive biomarker of radiation exposure to ionized gamma- and non-ionized UV-radiation. Steady state tryptophan (Trp) fluorescence and chemical analytical methods were used to evaluate the molecular integrity of Trp fluorophores and SH-groups in hair proteins and to assess the radiation induced damage quantitatively. It was found that human hair fibers were progressively damaged by exposure to both UV- and ionized gamma radiation. Damage to the hair was evidenced by a decrease in the fluorescence intensity as a result of observed depletion of the amino acid tryptophan as well as significant reduction in a number of free SH-groups in hair proteins. Hair damage was dose-dependent for exposures between 0 and 10.0 Gy and 0 - 20 j/cm2 of UV-radiation. Additional results demonstrate that hair-fibers exposed to gamma rays, with much higher quantum energy than UV, undergo a smaller extent of changes in Trp fluorescence than when exposed to lower or equal energy of UV-irradiation. The stable Trp fluorophore appears to be extremely sensitive to UV-radiation in contrast to the ionized gamma radiation whose damage is originated from the reaction of free radicals and direct deposition of energy. We conclude that fluorescence spectroscopy represents a useful tool in the quantitative evaluation of the radiation exposure and could also be used for the rapid and non-invasive assessment of radiation dose i.e. biodosimeter. The approach is simple, non-invasive and appears to have considerable potential that enables quantitative evaluation of radiation dose exposure in a single hair fiber.

关键词： Hair Fluorescence Radiation Chemical Integrity

锗粉中接近于安德森局域化相变的红外散射和吸收

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石油石化节能 2002年第6期14卷 50-52页

作者： j.gomez Rivas 霍光利燕山大学外语学院

使用自由电子激光器进行强散射和反射测量。研究了散射特性和光学吸收的波长依赖性 ,结果表明 ,样品接近于安德森局域化相变 (kls≈ 3) ,但仍未达到。这与最近报道的在类似的较低折射率粒子粉末 (GaAs)中的强光子局域化 (kls<1)

关键词：电子激光器散射反射测量安德森局域化相变红外散射光学吸收

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Sex Differences in the Effects of Sertraline and Stressors in Rats Previously Exposed to Restraint Stress

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journal of Biomedical Science and Engineering 2015年第7期8卷 399-419页

作者： Ines Pereira-Figueiredo juan Carro Luis j.Munoz Consuelo Sancho Orlando Castellano Ricardo gomez-Nieto Dolores E.Lopez Neuroscience Institute of Castilla y León/IBSAL University of SalamancaSalamancaSpain Department of Basic Psychology Psychobiology and MethodologyUniversity of SalamancaSalamancaSpain Animal Research Service University of SalamancaSalamancaSpain Department of Cell Biology and Pathology University of SalamancaSalamancaSpain

The serotonergic system in the brain plays a major role in mood and anxiety regulation when exposed to stress. The aim of the present study was to evaluate the effects of Sertraline administration in coping with stress using the behavioural paradigms of the acoustic startle reflex (ASR) and its prepulse inhibition (PPI) in both sexes. Wistar rats were divided into two groups: intact animals and exposed to restraint stress (RS) 3 times per day during 7 days, which were then subdivided into three other groups: injected with Sertraline (5 mg/kg/day) or the drug vehicle saline for 8 consecutive days, and non-injected. ASR and PPI values were analyzed along 4 sessions to determine behavioral changes. Upon it, we also determine the effects of acute immobilization stress analyzing physiological stress indicators in blood. Our data show sex differences in response to stress paradigms. RS affected more intensely males than females, disturbing the males’ growth and the long-term startle habituation that were not affected in females. PPI increased in the vehicle-injected animals when compared to baseline in both sexes, and Sertraline reversed more efficiently it in females. Moreover, despite both sexes exposed to stressful paradigms exhibited a significant increase in serum glutamic-oxaloacetic transaminase and lactate dehydrogenase enzymes when compared with intact controls, as well as leucopenia, some differences according to sex were found in the haemostatic response to stress. Notably, the repeated injections procedure disturbed the early response to stress, which Sertraline only attenuated in both sexes. Our data suggest that 8-day Sertraline administration is effective in reversing stress-induced changes in some physio-logical parameters, but insufficient to return immunological values to normality.

关键词： Behavior Habituation PPI Serotonin Startle

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橡胶树的解剖学及其对胶乳生产的影响(五)

热带作物译丛 1987年第1期 8-16页

作者： j.B.gomez 郝秉中吴继林

本文总结了近几十年来对橡胶树解剖学的研究。作者充分引述早期的文献,概述了这个领域的现状,以及叙述了作者为深入理解这一题材所作的研究。本文对研究巴西橡胶树的解剖学、采胶技术和育种的科技人员有参考价值。

关键词：乳管细胞大小木栓形成层树皮厚度解剖学组织厚度木质部导管橡胶树园艺作物胶乳

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橡胶无性系在叶片形态学和解剖学上的差异

热带作物译丛 1982年第2期 8-9页

作者： j.B.gomez 陈秋波

在影响蒸腾的地上部各个性状中,叶的特征,如气孔的多少、大小以及叶片的表面积都是很重要的。有关橡胶叶片气孔分布的资料很少。Rao 报道过叶片下表皮网状角质层的发生和特性以及气孔在下表皮的分布情况。Senanayake 研究过三个三叶橡... 详细信息

在影响蒸腾的地上部各个性状中,叶的特征,如气孔的多少、大小以及叶片的表面积都是很重要的。有关橡胶叶片气孔分布的资料很少。Rao 报道过叶片下表皮网状角质层的发生和特性以及气孔在下表皮的分布情况。Senanayake 研究过三个三叶橡胶种远轴的叶片的特性,发现所研究的植株单位面积的气孔密度是不相同的。随后,他和

关键词：差异气孔数下表皮相互影响无性系无性繁殖系品系(育种) 小叶平方毫米橡胶弹性体叶片解剖学

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应用收获指数测定巴西橡胶树的生产力

云南热作科技 1991年第2期14卷 30-34页

作者： j.B gomez 蔡嗣华

用“收获指数”这一概念来测定三叶橡胶生产力,迄今尚未得到普遍应用。本文试图得到三叶橡胶属中不同的种,一系列巴西橡胶无性系,以及一个特高产的Ⅰ级无性系收获指数的比较值。还讨论了与产量相关,亦即最终与收获指数相关的一些生理和... 详细信息

用“收获指数”这一概念来测定三叶橡胶生产力,迄今尚未得到普遍应用。本文试图得到三叶橡胶属中不同的种,一系列巴西橡胶无性系,以及一个特高产的Ⅰ级无性系收获指数的比较值。还讨论了与产量相关,亦即最终与收获指数相关的一些生理和结构参数。研究清楚表明,在三叶橡胶树属的各个种中,巴西橡胶的收获指数最高;其实生树群体中,各个体的收获指数也不一样,无性系之间和年份之间,收获指数的差异很明显,树龄的差异也很明显。胶树间的竞争以及胶树体内的同化分配和竞争生理损耗,也影响到胶树的生长,从而也是影响生产力的因素。可以认为,光合能的效率是有差异的,因特别受到无性系性状,树龄或许还有其它生理参数,包括树间竞争等的影响。显然,由于水份输送和乳管系统的生物合成能力的差异等引起的生理损耗的差异性,也可能影响这些生理参数。割胶过程也会影响损耗行为及其效率。因此,收获指数概念的这些特性,不仅在无性系比较时很有用,而且在测定无性系对割胶过程和对其它环境因素的敏感性时也很有用。

关键词：橡胶树生产力收获指数测定

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Benign retrorectal tumours: Contribution of laparoscopic approach

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Case Reports in Clinical Medicine 2013年第7期2卷 422-426页

作者： Victor j. Ovejero-gomez M. V. Bermudez-Garcia L. Martin-Cuesta A. Güezmes j. Villalba A. Ingelmo j. M. Bajo-Arenas Department of Gynaecology Hospital Sierrallana Cantabria Spain Department of Pathology Hospital Sierrallana Cantabria Spain Department of Radiology Hospital Sierrallana Cantabria Spain Department of Surgery Hospital Sierrallana Cantabria Spain

Introduction: Presacral tumours are extremely rare entities as the asymptomatic retrorectal mass, although its clinical presentation includes infectious complications and signs of malignant degeneration. Magnetic resonance imaging is the most efficient imaging study for its diagnosis. The treatment of choice is complete surgical excision and traditional approaches are mainly through abdominal, posterior and perineal approach, depending on anatomical characteristics of the lesion. Laparoscopic excision of these retrorectal lesions has been reported in a few cases. Patients and methods: We report two cases of 38 and 24-year-old women who complained of anorectal symptoms and were diagnosed as retrorectal tumour by imaging studies. One of them was infected. Both cases were resected by means of laparoscopic techniques. There was no surgical complication and they were discharged on the 3rd and 4th postoperative day, respectively. Histopathologic findings revealed benign cystic teratoma in both cases. A follow-up after 36 months showed no recurrence. Our surgical endoscopic technique and a brief review of perioperative cares are presented and discussed. Discussion: Laparoscopic excision could be indicated in selected retrorectal tumours and a great surgeon’s resolve is always required. A meticulous dissection must be performed in order to identify and preserve vital structures. It’s only absolute contraindications seemed to be the suspicion of malignancy and operative inexperience. Conclusions: The complete laparoscopic removal of presacral lesions is a responsible surgical procedure which offers advantages from the sanitary and aesthetic point of view. This new endoscopic indication could be considered probably as a better technique than open approach in selected patients.

关键词： Retrorectal Tumour Laparoscopy Surgical Technique