Surface attachment of protein fibrils via covalent modification strategies.

Chemical control of surface functionality and topography is an essential requirement for many technological purposes. In particular, the covalent attachment of monomeric proteins to surfaces has been the object of intense studies in recent years, for applications as varied as electrochemistry, immuno-sensing, and the production of biocompatible coatings. Little is known, however, about the characteristics and requirements underlying surface attachment of supramolecular protein nanostructures. Amyloid fibrils formed by the self-assembly of peptide and protein molecules represent one important class of such structures. These highly organized beta-sheet-rich assemblies are a hallmark of a range of neurodegenerative disorders, including Alzheimer's disease and type II diabetes, but recent findings suggest that they have much broader significance, potentially representing the global free energy minima of the energy landscapes of proteins and having potential applications in material science. In this paper, we describe strategies for attaching amyloid fibrils formed from different proteins to gold surfaces under different solution conditions. Our methods involve the reaction of sulfur containing small molecules (cystamine and 2-iminothiolane) with the amyloid fibrils, enabling their covalent linkage to gold surfaces. We demonstrate that irreversible attachment using these approaches makes possible quantitative analysis of experiments using biosensor techniques, such as quartz crystal microbalance (QCM) assays that are revolutionizing our understanding of the mechanisms of amyloid growth and the factors that determine its kinetic behavior. Moreover, our results shed light on the nature and relative importance of covalent versus noncovalent forces acting on protein superstructures at metal surfaces.

热障涂层界面形貌尺寸与残余应力的关系

利用ANSYS有限元分析软件对热障涂层中的残余应力进行了模拟分析，得出了界面形貌尺寸与残余应力之间的关系。模拟结果表明，热障涂层中的残余应力是界面形貌尺寸的函数。这些结论为提高涂层界面结合强度的热障涂层界面造形提供了理论支持，也为热障涂层界面的优化提供了指导意见。

Study on Microstructure and Nanomechanics Properties of Antibacterial Bone China

Fracture appearance, surface and nanomechanics properties of antibacterial ceramics contairing rare earth phosphate composite antibacterial materials were characterized and measured by SEM, AFM and Nanoindenter, respectively. Results show that grain of fracture surface of antibacterial ceramics grows uniform refinement topography of bubble break-up appears at the surface, which is flat and has liquid character, by adding the phosphate composite containing rare earth, nevertheless needle-like crystal and granular outgrowth form at fracture surface and surface of common ceramics, respectively. Young's modulus of antibacterial ceramic film is 74. 397 GPa and hardness is 8. 134 GPa, which increses by 4.4﹪ and 1.6﹪ comparing with common ceramics, respectively. Loading curves of two kind of ceramics have obvious nonlinear character under 700 nm and linear character between 700 ～ 1000 nm, and unloading curve have obvious linear character.

Two-Dimensional Kinematic Wave Model of Overland-Flow

A two-dimensional kinematic wave model was developed for simulating runoff generation and flow concentration on an experimental infiltrating hillslope receiving artificial rainfall. Experimental observations on runoff generation and flow concentration on irregular hillslopes showed that the topography of the slope surface controlled the direction and flow lines of overland flow. The model-simulated results satisfactorily compared with experimental observations. The erosive ability of the concentrated flow was found to mainly depend on the ratio of the width and depth of confluent grooves.

An Efficient Front-Tracking Method For Fully Nonlinear Interfacial Waves

A fully nonlinear and dispersive model within the framework of potential theory is developed for interfacial (2-layer) waves. To circumvent the difficulties arisen from the moving boundary problem a viable technique based on the mixed Eulerian and Lagrangian concept is proposed: the computing area is partitioned by a moving mesh system which adjusts its location vertically to conform to the shape of the moving boundaries but keeps frozen in the horizontal direction. Accordingly, a modified dynamic condition is required to properly compute the boundary potentials. To demonstrate the effectiveness of the current method, two important problems for the interfacial wave dynamics, the generation and evolution processes, are investigated. Firstly, analytical solutions for the interfacial wave generations by the interaction between the barotropic tide and topography are derived and compared favorably with the numerical results. Furthermore simulations are performed for the nonlinear interfacial wave evolutions at various water depth ratios and satisfactory agreement is achieved with the existing asymptotical theories. (c) 2008 Elsevier Inc. All rights reserved.

An Electrowetting Model For Rough Surfaces Under Low Voltage

Electrowetting is one of the most effective methods to enhance wettability. A significant change of contact angle for the liquid droplet can result from the surface microstructures and the external electric field, without altering the chemical composition of the system. During the electrowetting process on a rough surface, the droplet exhibits a sharp transition from the Cassie-Baxter to the Wenzel regime at a low critical voltage. In this paper, a theoretical model for electrowetting is put forth to describe the dynamic electrical control of the wetting behavior at the low voltage, considering the surface topography. The theoretical results are found to be in good agreement with the existing experimental results. (c) Koninklijke Brill NV, Leiden, 2008.

Limiting States Of Internal Wave Rays

Existing models of baroclinic tides are based upon the "traditional approximation'', i. e., neglect of the horizontal component of the Earth's rotation, leading to a well- known conclusion that no freely propagating internal waves can exist beyond the critical latitude and the wave rays are symmetric to the vertical. However, recent studies have contended that the situation may change if both the vertical and horizontal components of the Earth's rotation are taken into account. With the full account of the Coriolis force, characteristics of the internal wavefield generated by tidal flow over uneven topography are investigated. It is found that "nontraditional effects'' profoundly change not only the dynamics of internal waves but also the rate at which the barotropic tidal energy is fed into the internal wavefield. Discarding the traditional approximation, internal waves are proved to be able to generate poleward of the critical latitude, rays of which are no longer symmetric and the limiting values of ray angles become greater or less than 90 degrees, depending on the local latitude and the direction of ray. More importantly, in contrast to the predictions of models based upon the traditional approximation, a substantial conversion occurs in the situations when stratification is so weak that the buoyancy frequency is below the tidal one.

Estado forestal del Pinus caribaea Morelet var. Hondurensis en el Pinal, Laguna de Perlas, RAAS

Tbe present study was carried out in the strip of land coast between Pearls Lagoon community and the Caribbean sea, in the nearness of Pinar lagoon, 25 km to the north of Bluefields. The geographical coordinates of the area are 12" 13' N and 83" 42' west. Tbe climate presents an annua! rninfall of 4 250 mm, an avera· ge temperature of 26 "C and a relative humidity of 89 %. The topography is plain and tbe elevation oscillates between O· 10 masl. The ma.in objective of the study was to evaluate the forest conditions in which forest of P. Caribaea var .. Jwndurei'ISis ealled the Pinal are found. The methodology employed consisted of gathering all information using air pllotographs and topograpbieal maps to defined the area and stands group (designed A, B, C, D, E, F and G). Two block and seven stands were found, in which invent.ory lines with sample plots of 500 m1 each one were employed to measure the indivíduals with DBH over 10 cm. The intensily it shows ís of !5% and was measured diameter, height, age and other. In tbis forest there where found seven stands with a total area covered with pine of 312.42 has. The average age is 23 years and estirnated total volume of 97.4 ms of wood. The density is of 60,61 trees hectare, with an average volume of 13.02 m3 /has and a commercial volume of 8.29 m' 1 has. Where found lndices of place 12 (stands G), 9 y 6. Besides, the 6.3.64 % of the trees has a satisfactory tendency of growlh (quality l and 2). lt can be concluded that the resource is in badly state due to intensive exploitations and annual f!fCS; is a young forest (23 years old), dotninated by índi viduals of small diameters (10-25 cm) and medium height (5-25 m); the available areas or with possibilities of being planting are: estimated in 468.64 has. This forest has a half annual increment of 1.4.3 cm/year, which is considered excellent and is c1assified with Clas P-III, FAO Classification by forests stratification.

Some considerations on coastal processes relevant to sea level rise

The effects of potential sea level rise on the shoreline and shore environment have been briefly examined by considering the interactions between sea level rise and relevant coastal processes. These interactions have been reviewed beginning with a discussion of the need to reanalyze previous estimates of eustatic sea level rise and compaction effects in water level measurement. This is followed by considerations on sea level effects on coastal and estuarine tidal ranges, storm surge and water level response, and interaction with natural and constructed shoreline features. The desirability to reevaluate the well known Bruun Rule for estimating shoreline recession has been noted. The mechanics of ground and surface water intrusion with reference to sea level rise are then reviewed. This is followed by sedimentary processes in the estuaries including wetland response. Finally comments are included on some probable effects of sea level rise on coastal ecosystems. These interactions are complex and lead to shoreline evolution (under a sea level rise) which is highly site-specific. Models which determine shoreline change on the basis of inundation of terrestrial topography without considering relevant coastal processes are likely to lead to erroneous shoreline scenarios, particularly where the shoreline is composed of erodible sedimentary material. With some exceptions, present day knowledge of shoreline response to hydrodynamic forcing is inadequate for long-term quantitative predictions. A series of interrelated basic and applied research issues must be addressed in the coming decades to determine shoreline response to sea level change with an acceptable degree of confidence. (PDF contains 189 pages.)

Little known parts of Panama

An account of Pittier's travels around Panama. Written as a travel guide, Pittier describes the flora and fauna of the different regions as well as the topography, people and geology of the area.

Design,optimization and in vivo evaluation of non-viral vectors for gene therapy. Applications in ocular disorders

227 págs.

Biological production in the Eastern Pacific Ocean

ENGLISH:The present paper is principally concerned with the geographic distribution of the standing crop and production of phytoplankton at the surface of the eastern Pacific, east of 130°W and between 10°N and 33°S, as reflected by recently collected data. In addition we discuss some of the more obvious, general relationships among thermocline topography, nutrient concentration, and the various trophic levels from primary production to fish production. The limited data do not allow a seasonal study. We have therefore mapped all of the data together regardless of the time of collection, but do not wish to imply that the physical, chemical and biological system is without seasonal or periodic change. SPANISH:Como lo reflejan los datos recientemente recolectados, el presente trabajo está dedicado principalmente a la distribución geográfica de las cosechas estables y a la producción del fitoplancton en la superficie del Pacífico Oriental, al este de los 130°W y entre los 10°N y 33°S. Además discutimos algunas de las relaciones generales más obvias entre la topografía de la termoclina, la concentración de los nutrientes, y los varios niveles tróficos, desde la producción primaria hasta la producción de los peces. Los datos limitados no permiten un estudio estacional. Por lo tanto, hemos combinado todos los datos no tomando en cuenta el tiempo de la recolección, pero no queremos implicar que no existen cambios estacionales o periódicos en el sistema físico, químico y biológico.

Currents observed in Panama Bay during September-October 1958

ENGLISH: During the period extending from late August to early October 1958 the United States Navy Hydrographic Office (now the United States Oceanographic Office) undertook a program of current observations in the western part of Panama Bay. The specifications of the survey called for half-hourly monitoring of currents at three depths at each of six locations, one for thirty days and five for five days. Although not all these objectives were realized because of instrument malfunctions and failures, sufficient data were collected at five stations to provide a fairly detailed description of the current pattern as it existed at the times of observation. This report is concerned first with a discussion of those data and the procedures used to reduce them to the tidal and net current components and second, with the effects on the current pattern of tidal amplitude, bottom topography and bottom friction. SPANISH: Durante el período entre fines de agosto y principios de octubre de 1958, la United States Navy Hydrographic Office (ahora la United States Navy Oceanographic Office) tomó a su cargo un programa para observar las corrientes en la parte occidental de la Bahía de Panamá. De acuerdo con las especificaciones del proyecto, las observaciones de las corrientes debían hacerse cada media hora a tres profundidades en cada una de seis localidades; en una de ellas durante treinta días yen las otras cinco durante cinco días. A pesar de que no todos estos objetivos fueron cumplidos a causa del mal funcionamiento y fallas instrumentales, se recogieron suficientes datos en cinco estaciones, como para proporcionar una descripción bastante detallada de la pauta de las corrientes, tal como existía durante las observaciones. Este informe se refiere, primero, al análisis y examen de dichos datos y a los procedimientos empleados para reducir éstos a los componentes de las corrientes netas y a los componentes de las corrientes durante la mareas, y segundo, al efecto que tienen sobre la pauta de las corrientes la fluctuación de las mareas, la topografía del fondo y la fricción del fondo.

Dextran and protamine-based solid lipid nanoparticles as potential vectors for the treatment of X-linked juvenile retinoschisis

This is a copy of an article published in the Human gene therapy © 2012 copyright Mary Ann Liebert, Inc.; Human gene therapy is available online at: http://online.liebertpub.com.

Sustainable management of water bodies for small-scale fisheries resorces research and development

Abstract The rapid growth of both formal and informal high density urban settlements around major water resources has led to increased pollution of streams, rivers, lakes and estuaries, due to contaminated runoff from these developments. The paper identified major contaminants to be : organic waste (sewage), industrial effluent, pesticides and litter. Pollutant loads vary depending on the hydrology of the urban area, local topography and soil conditions. In some instances, severe pollution of neighbouring and downstream water courses has been observed. The management of catchment land uses, riparian zones, in stream habitat, as well as in stream water flow patterns and quality are necessary in order to sustain the integrity and "health" of water resources, for fisheries and other developments. As such, attempts to ensure a certain level of water quality without attention to other aspects will not automatically ensure a "healthy" ecosystem even as fish habitat. Proper management leads to better water quality and conducive environment for increased fish production