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Bioinspired Dry Adhesive Materials and Their Application in Robotics： A Review

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Journal of Bionic Engineering 2016年第2期13卷 181-199页

作者： Yasong Li jeffrey Krahn Carlo Menon MENRVA Research Group School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC V5A 1S6 Canada

Dry adhesives inspired from climbing animals, such as geckos and spiders, rely on van der Waals forces to attach to the opposing surface. Biological fibrillar dry adhesives have a hierarchical structure closely resembling a tree： the surface of the skin on the animal＇s feet is covered in arrays of slender micro-fibrils, each of which supports arrays of fibrils in submicron dimensions. These nano-meter size fibrils can conform closely to the opposing surfaces to induce van der Waals interaction. Bioinspired dry adhesives have been developed in research laboratories for more than a decade. To mimic the biological fibrillar adhesives, fibrillar structures have been prepared using a variety of materials and geometrical arrangements. In this review article, the mechanism and selected fabrication methods of fibrillar adhesives are summarized for future reference in adhesive development. Robotic applications of these bioinspired adhesives are also introduced in this article. Various successful appli- cations of bioinspired fibrillar adhesives can shed light on developing smart adhesives for use in automation.

关键词： bioinspired gecko adhesive van der Waals forces biomimetic climbing robot bioinspired tape

A zoological perspective on payments for ecosystem services

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Integrative Zoology 2007年第2期2卷 68-78页

作者： jeffrey A.McNEELY IUCN–The World Conservation Union GlandSwitzerland

The concept of payments for ecosystem services is being developed as an important means of providing a more diverse flow of benefits to people living in and around habitats valuable for *** Kyoto Protocol,under the United Nations Framework Convention on Climate Change,includes a Clean Development Mechanism to provide for payments for certain forms of carbon sequestration that may benefit animal species(at least as an incidental benefit).Other market-based approaches for paying for carbon sequestration services outside the Kyoto framework are being promoted in various parts of the *** common form of payment for ecosystem services is compensating upstream landowners for managing their land in ways that maintain downstream water quality;this can include habitat management that benefits wild animal *** biodiversity itself is difficult to value,it can be linked to other markets,such as certification in the case of sustainably-produced forest *** paper expands on some of the markets for ecosystem services that also benefit wildlife,identifies relevant sources of information,and highlights some of the initiatives linking such markets to poverty *** markets work for ecosystem services requires an appropriate policy framework,government support,operational institutional support,and innovation at scales from the site level to the national *** have much to contribute to all of these steps.

关键词： biodiversity carbon trading ecosystem services payments watersheds

Fabrication and Testing of Self Cleaning Dry Adhesives Utilizing Hydrophobicity Gradient

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Journal of Bionic Engineering 2015年第2期12卷 270-275页

作者： Enrico Bovcro jeffrey Krahn Carlo Menon MENRVA Lab School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC Canada V5A 1S6

In this paper we present a method to create a hydrophobicity gradient on the surface of a Polydimethylsiloxane （PDMS） dry adhesive. The method consists of the partial silanization of the surface of the dry adhesive by Chemical Vapour Deposition （CVD） of octadecyltrichlorosilane （OTS）. The partial silanization of the surface of the sample results in a hydrophobic to hy- drophilic gradient across the surface of the dry adhesive. The resulting change in hydrophobicity across the surface of the dry adhesive results in the uphill motion of a droplet of water, which appears to be directly proportional to the area of contact between the droplet and the adhesive. Normal adhesion testing is performed to quantify the effect of the hydrophobic gradient across the surface of the sample. While a variation in adhesion are only minimally affected by the silanization, and the motion strength across the sample is measured, the adhesive properties of the droplet of water doesn＇t cause any loss of adhesion.

关键词： dry adhesion self cleaning hydrophobic silanization polymers PDMS

Using economic instruments to overcome obstacles to in situ conservation of biodiversity

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Integrative Zoology 2006年第1期1卷 25-31页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

The leading direct cause of the loss of biodiversity is habitat alteration and *** we are to address this cause directly,we need to find ways of changing the behavior of rural *** has shown that this is done most effectively through the use of economic instruments,ranging from taxes that discourage over-exploitation,to direct payments for conservation activities carried out by rural land-owners or those occupying the *** many parts of the world,governments provide incentives such as tax breaks to private *** countries recognize specific use rights on particular parts of the land,enabling the land-owners to earn appropriate *** many protected areas have resident human populations,it is especially important that they be encouraged to contribute to the objectives of the protected area,and economic incentives offer an important way of doing so;they might,for example,be given employment in the protected area or in associated tourism *** payments to farmers for conserving watersheds is becoming increasingly popular,in both developed and developing *** conservation will require both removing perverse subsidies and developing a wide range of approaches for rewarding land-owners for biodiversity conservation activities.

关键词： ecosystem services incentives indigenous peoples protected areas resource rights

Systems or species? Approaches to conservation for the 21st century

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Integrative Zoology 2006年第2期1卷 86-95页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

One of the hot debates in the conservation community is whether to focus on individual species(for example,through species recovery plans,or lists of threatened species)or on systems approaches(such as the ecosystem approach advocated by the Convention on Biological Diversity).This paper will discuss some of the various options,before reaching a conclusion that both approaches are valid and mutually reinforcing,and that the dichotomy is a false *** more importantly,no conservation investment is likely to be effective if economic,social,and political factors are driving in the opposite ***,we need multiple approaches that build a stronger political constituency,new ways of providing knowledge for decisions,better ways of mobilizing information and dynamic approaches that enable us to adapt to changing conditions,and new ways to generate funding for conservation.

关键词： biodiversity conservation ecosystem approach protected areas species

Minimally invasive treatment of pancreatic necrosis

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World Journal of Gastroenterology 2012年第46期18卷 6829-6835页

作者： Brian Bello jeffrey B Matthews Department of Surgery School of Medicine University of Chicago

AIM: To systematically review these minimally invasive approaches to infected pancreatic necrosis. METHODS: We used the MEDLINE database to investigate studies between 1996 and 2010 with greater than 10 patients that examined these techniques. Using a combination of Boolean operators, reports were retrieved addressing percutaneous therapy (341 studies), endoscopic necrosectomy (574 studies), laparoscopic necrosectomy via a transperitoneal approach (148 studies), and retroperitoneal necrosectomy (194 studies). Only cohorts with at least 10 or more patients were included. Non-English papers, letters, animal studies, duplicate series and reviews without original data were excluded, leaving a total of 27 studies for analysis. RESULTS: Twenty-seven studies with 947 patients total were examined (eight studies on percutaneous approach; ten studies on endoscopic necrosectomy; two studies on laparoscopic necrosectomy via a transperitoneal approach; five studies on retroperitoneal necrosectomy; and two studies on a combined percutaneous-retroperitoneal approach). Success rate, complications, mortality, and number of procedures were outcomes that were included in the review. We found that most published reports were retrospective in nature, and thus, susceptible to selection and publication bias. Few reports examined these techniques in a comparative, prospective manner. CONCLUSION: Each minimally invasive approach though was found to be safe and feasible in multiple reports. With these new techniques, treatment of infected pancreatic necrosis remains a challenge. We advocate a multidisciplinary approach to this complex problem with treatment individualized to each patient.

关键词： Acute pancreatitis Pancreatic abscess Pancreatic necrosis Necrosectomy Laparoscopic necrosectomy

Hematological changes during androgen deprivation therapy

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Asian Journal of Andrology 2012年第2期14卷 187-192页

作者： Mathis Grossmann jeffrey D Zajac Department of Medicine Austin Health/Northern Health University of Melbourne Heidelberg Vic. 3084 Australia

Androgen deprivation therapy （ADT） has been associated with a plethora of adverse effects, consistent with the androgen dependency of multiple reproductive and somatic tissues. One such tissue is the hemopoietic system, and one of the most predictable consequences of ADT is the development of anemia. Although anemia caused by ADT is rarely severe, ADT is often given to frail, elderly men with increased susceptibility to anemia due to multiple other causes. ADT-associated anemia may contribute to fatigue and reduced quality of life （QoL） in such men, although this requires further study. While anemia is an independent risk factor of mortality in men with prostate cancer, it is not known whether treatment of ADT-associated anemia alters clinically important outcomes, or whether treatment affects mortality. Awareness of the phenomenon of ADT-induced anemia should avoid unnecessary work-up in mild cases of normocytic normochromic anemia. However, assessment and treatment of more severe anemia may be required. This should be determined on an individual basis. In contrast to the weli-descrihed actions of ADT on erythropoiesis, its effect on other hemopoietic lineages has been less well elucidated. While preclinical studies have found roles for androgens in maturation and differentiated function of neutrophils, lymphocytes and platelets, the implications of these findings for men with prostate cancer receiving ADT require further studies.

关键词： anemia androgen deprivation therapy (ADT) prostate cancer

INVARIANCE AND STABILITY OF THE PROFILE EQUATIONS OF GEOMETRIC OPTICS

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Acta Mathematica Scientia 2011年第6期31卷 2141-2158页

作者： Guy Mtivier jeffrey Rauch Institut de Mathmatiques de Bordeaux Universit de Bordeaux Department of Mathematics University of Michigan

The profile equations of geometric optics are described in a form invariant under the natural transformations of first order systems of partial differential equations. This allows us to prove that various strategies for computing profile equations are equivalent. We prove that if L generates an evolution on L2 the same is true of the profile equations. We prove that the characteristic polynomial of the profile equations is the localization of the characteristic polynomial of the background operator at （y, dφ（y）） where φ is the background phase. We prove that the propagation cones of the profile equations are subsets of the propagation cones of the background operator.

关键词： geometric optics profile equation localisation vector bundles propagation cones

At the Edge(Always):An Interview with jeffrey Schnapp

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Journal of Foreign Languages and Cultures 2022年第2期6卷 10-18页

作者： jeffrey Schnapp Harvard University

In this interview,jeffrey Schnapp conceptualizes Digital Humanities,Knowledge Design and Experimental Humanities,seen as innovative frameworks,aimed at propitiating a radically new understanding of the current challenges of the contemporary *** overwhelming presence of digital media and artificial intelligence is scrutinized by Schnapp in order to produce theory literally at the edge.

关键词： Digital Humanities Knowledge Design Curatorship Experimental Humanities