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Influence of Functionalization on the Structural and Mechanical Properties of Graphene

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Computers, Materials & Continua 2017年第2期53卷 109-127页

作者： L.S.Melro L.R.jensen Department of Materials and Production Aalborg UniversityAalborgDenmark Corresponding author:liliana@m-tech.aau.dk

Molecular dynamics simulations were applied in order to calculate the Young’s modulus of graphene functionalized with carboxyl,hydroxyl,carbonyl,hydrogen,methyl,and ethyl *** influence of the grafting density with percentages of 3,5,7,and 10%and the type of distribution as a single cluster or several small clusters were also *** results show that the elastic modulus is dependent on the type of functional *** increasing coverage density also evidenced a decrease of the Young’s modulus,and the organization of functional groups as single cluster showed a lesser impact than for several small ***,the bond length and angle distribution probability analyses reveal that lengths and angles are affected with increasing functionalization suggesting more out-of-plane displacements of the carbon atoms within the graphene structure.

关键词： Functionalization graphene molecular dynamics Young’s modulus structural properties

Pharmacologic management of post-tonsillectomy pain in children

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2021年第3期7卷 186-193页

作者： Daniel R.jensen Division of Otolaryngology Children’s Mercy HospitalKansas CityMOUSA Department of Surgery University of Missouri-Kansas City School of MedicineKansas CityMOUSA

Tonsillectomy is a very common procedure in children,often performed on an outpatient *** postoperative pain is common,and can be *** a large number of available analgesic medications,often employed in combination,achieving adequate pain control remains a persistent *** suggests a tendency among caregivers to undertreat pain,and a need for detailed care instructions and education to ensure adequate pain ***,ongoing questions regarding the safety and efficacy of the most commonly used medications have led to wide variance in practice patterns and continuous reassessment through research that yields sometimes conflicting *** review summarizes the current state of the literature and presents a management approach which attempts to maximize pain control while minimizing potential harm with combinations of medications and modification based on patient-specific factors.

关键词： Pediatric tonsillectomy Tonsillectomy pain Postoperative analgesia

Stereotactic body radiation therapy in patients with hepatocellular carcinoma: A mini-review

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World Journal of Gastrointestinal Oncology 2019年第5期11卷 367-376页

作者： Sabine Gerum Alexandra D jensen Falk Roeder Department of Radiation Oncology University Hospital LMU Munich Department of Radiation Oncology University Hospital Gie?en and Marburg CCU Molecular Radiation Oncology German Cancer Research Center Department of Radiotherapy and Radiation Oncology Paracelsus Medical University

Stereotactic body radiation therapy(SBRT) is an emerging treatment for hepatocellular carcinoma. This technique results in excellent local control rates with favorable toxicity profile despite being predominantly used in heavily pretreated patients or those unsuitable for other local therapies. SBRT may be used as a sole treatment or in combination with other local therapies as well as a bridging strategy for patient awaiting liver transplants. This brief review describes current practice of SBRT with respect to radiation technique, patient selection and treatment concepts. It summarizes available evidence from retroand prospective studies evaluating SBRT alone, SBRT in combination with other treatments and SBRT compared to other local treatment approaches.

关键词： Hepatocellular carcinoma Stereotactic body radiation therapy Local-ablative treatment Combination approaches Mini-review

Intraventricular neurocysticercosis: Presentation, diagnosis and management

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Asian Pacific Journal of Tropical Medicine 2016年第8期9卷 792-795页

作者： Tomas Ostergaard jensen Jeffrey John Post Department of Infectious Diseases Prince of Wales Hospital

Neurocysticercosis is thought to be the most common helminthic infection of the central nervous system and its epidemiology is changing due to increasing travel and *** to guide management of the intraventricular form is *** aimed to review the clinical presentation,diagnosis and treatment of intraventricular neurocysticercosis with reference to two recent cases seen at our *** intraventricular variant of neurocysticercosis is less common than parenchymal disease and usually presents with acutely raised intracranial pressure and untreated it progresses rapidly with high *** diagnosis is based on imaging and serological tests but more invasive testing including histopathological examination of surgically acquired tissue specimens is sometimes *** is mainly surgical,using a neuroendoscopic approach if *** should also receive antihelmintic treatment with concomitant corticosteroids to reduce the incidence of shunt failure if a ventricular shunt is inserted and to treat viable lesions elsewhere.

关键词： Taenia solium Cysticercosis Neurocysticercosis Intraventricular Human Adult

Significance of endothelial dysfunction in the pathogenesis of early and delayed radiation enteropathy

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World Journal of Gastroenterology 2007年第22期13卷 3047-3055页

作者： Junru Wang Marian Boerma Qiang Fu Martin Hauer-jensen Department of Surgery University of Arkansas for Medical Sciences United States Department of Pharmaceutical Sciences University of Arkansas for Medical Sciences United States Department of Microbiology and Immunology University of Arkansas for Medical Sciences United States Department of Surgery University of Arkansas for Medical Sciences Surgical Service Central Arkansas Veterans Healthcare System4 Little Rock AR United States

This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented interventions aimed at reducing the risk of radiation enteropathy. Studies published in the biomedical literature during the past four decades and cited in PubMed, as well as clinical and laboratory data from our own research program are reviewed. The risk of injury to normal tissues limits the cancer cure rates that can be achieved with radiation therapy. During treatment of abdominal and pelvic tumors, the intestine is frequently a major close-limiting factor. Microvascular injury is a prominent feature of both early （inflammatory）, as well as delayed （fibroproliferative） radiation injuries in the intestine and in many other normal tissues. Evidence from our and other laboratories suggests that endothelial dysfunction, notably a deficiency of endothelial thrombomodulin, plays a key role in the pathogenesis of these radiation responses. Deficient levels of thrombomodulin cause loss of vascular thromboresistance, excessive activation of cellular thrombin receptors by thrombin, and insufficient activation of protein C, a plasma protein with anticoagulant, anti-inflammatory, and cytoprotective properties. These changes are presumed to be critically involved in many aspects of early intestinal radiation toxicity and may sustain the fibroproliferative processes that lead to delayed intestinal dysfunction, fibrosis, and clinical complications. In conclusion, injury of vascular endothelium is important in the pathogenesis of the intestinal radiation response. Endothelial-oriented interventions are appealing strategies to prevent or treat normal tissue toxicity associated with radiation treatment of cancer.

关键词： Endothelial cells Thrombomodulin Proteinase-activated receptors Radiation injuries Radiation enteropathy

The Emergence of a Globalized System for Disaster Risk Management and Challenges for Appropriate Governance

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International Journal of Disaster Risk Science 2015年第1期6卷 87-93页

作者： Steven Jjensen Shirley Feldmann-jensen David MJohnston Nancy ABrown College of Health and Human Services California State University GNS Science School of Psychology Joint Centre of Disaster ResearchMassey University

Disaster risk management(DRM) is undergoing noteworthy changes, reflecting the broader shifts in global and local levels of governance. At the global level two significant changes are of interest:(1) the shift from monolithic structures of global governance to a wide range of organizations that can be brought together for specific purposes and(2) the emergence of a globalized system of DRM, with technological, organizational, and institutional capacities enhancing DRM’s ability as a unit in near real time across the globe. At the local level there is an increase in ability to govern and develop creative solutions for complex problems that follow rapid urbanization. The importance of getting the global–local interface to work in tandem has been highlighted by recent hazard events, such as the 2011 Tohoku Earthquake and Tsunami. From a broad view of global and local shifts, a strategic role is becoming clearer at the national level for enhancing the relationships between the global and local levels. Through the influence of a globalized system of DRM, the local level can significantly improve its capacity without the heavy investment that might have been required to develop these capacities in isolation. One key to achieving this is adiffusion of DRM higher education, supported by an enhanced system of information flow.

关键词： Disaster risk management Global governance Globalization Globalized systems Local governance National governance

Electrochemical probing into the active sites of graphitic-layer encapsulated iron oxygen reduction reaction electrocatalysts

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Science Bulletin 2018年第1期63卷 24-30页

作者： Lijie Zhong Jens Oluf jensen Lars Nilausen Cleemann Chao Pan Qingfeng Li Department of Energy Conversion and Storage Technical University of Denmark

The graphitic-layer encapsulated iron-containing nanoparticles(G@Fe) have been proposed as a potential type of active and stable non-precious metal electrocatalysts(NPMCs) for the oxygen reduction reaction(ORR). However, the contribution of the encapsulated components to the ORR activity is still unclear compared with the well-recognized surface coordinated FeN_x/C structure. Using the strong complexing effect of the iron component with anions, cyanide(CN^-) in alkaline and thiocyanate(SCN^-) in acidic media, the metal containing active sites are electrochemically probed. Three representative catalysts are chosen for a comparison including the as-prepared encapsulated G@Fe, commercial Fe/N/C catalyst with iron–nitrogen coordinated surface functionalities and molecular iron phthalocyanine(Fe Pc) containing well-defined structures and compositions. It was found that all samples showed significant shifts of half-wave potentials indicating that surface Fe coordinated sites in all cases. The G@Fe catalyst showed the weakest poisoning effect(the lowest shifts of half-wave potential) compared to the Fe/N/C and Fe Pc catalysts in both electrolytes. These results could be explained that the encapsulated iron components influence the FeN_x/C and/or N_xC surface functionality.

关键词： Encapsulated Fe catalysts Oxygen reduction reaction Ion poisoning Active sites NPMCs

A whiter shade of male： Color background matching as a function of size and sex in the yellow shore crab Hemigrapsus oregonensis （Dana, 1851）

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Current Zoology 2015年第4期61卷 729-738页

作者： Gregory C. jensen Michael S. EGNOTOVICH School of Aquatic and Fishery Sciences Box 355020 University of Washington Seattle WA 98195 USA

Juveniles of the shore crab Hemigrapsus oregonensis are highly variable in color, ranging from the typical yellowish- green of adults to pure white and myriad patterns of white mottling and other disruptive markings, but large individuals with white coloration appear to be very rare. Using image analysis to quantify the relative ＂whiteness＂ of beaches, we sampled crabs from nine locations in Washington State that varied widely in their amount of shell fragments and other light-colored material. The total proportion of white individuals in the different locations was strongly correlated to the proportion of white material on the beaches, but there was a striking difference between sexes. Although white specimens of both sexes declined significantly at sizes above 10 mm carapace width, white females generally persisted throughout the entire female size range on lighter-colored beaches while white males larger than 10 mm were virtually absent from all of the sampled populations. Pure white males held on dark backgrounds in captivity remained white, as they lack the dark chromatophores in their hypoderrnis needed to change color; off-white males became darker and in some cases lightened up again when transferred back to a white background. Behavioral differences between the sexes may result in differential mortality of white individuals by visual predators [Current Zoology 61 （4） 729-738, 2015 ].

关键词： Camouflage Color Polymorphism Disruptive patterns Crabs

Temperature dependence of dielectric breakdown of silicone-based dielectric elastomers

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International Journal of Smart and Nano Materials 2020年第2期11卷 129-146页

作者： Liyun Yu Sindhu Vudayagiri Lucy Ajakaiye jensen Anne Ladegaard Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkLyngbyDenmark

A large number of insulation/dielectric failures in power systems are related to thermally-induced dielectrical breakdown,also known as‘thermal breakdown’,at higher operating *** this work,the thermal breakdown behavior of typical silicone formulations,used as dielectrics in stretchable electronic devices,is analyzed at practically relevant operating temperatures ranging from 20℃ to 80℃.An effective way of delaying the thermal breakdown of insulating materials is to blend micro-or nano-sized inorganic particles with high thermal conductivity,to dissipate better any losses generated during energy ***,two types of commercial silicone formulations,blended with two types of rutile hydrophobic,high-dielectric TiO_(2) fillers,are investigated in relation to their dielectric properties,namely,relative permittivity,the dissipation factor,and electrical breakdown *** breakdown strengths of these silicone composites are subsequently evaluated using Weibull analysis,which indicates a negative correlation between temperature and shape parameter for all compositions,thus illustrating that the homogeneity of the samples decreases in line with temperature,but the breakdown strengths nevertheless increase initially due to the trapping effect from the high-permittivity fillers.

关键词： Silicone elastomers titanium dioxide fillers dielectric breakdown strength Weibull temperature