Nanometer-thick equilibrium films: the interface between thermodynamics and atomistics

Nanometer-thick films at interfaces and surfaces exist in various materials and can substantially influence their properties. Whether these films are an equilibrium or transient state is debated. To address this question, we equilibrated 1.2-nanometer-thick films at gold-sapphire interfaces in the presence of anorthite glass and measured the solid-solid interface energy. The equilibrated film significantly reduced the interfacial energy and could be described by the Gibbs adsorption isotherm expanded to include structure in addition to chemical excess. Unlike artificially made conventional thin films, these films do not break up during equilibration and offer an alternative design criterion for thin-film technology. These results demonstrate that nanometer-thick films at interfaces and surfaces can be an equilibrium state and included in phase diagrams with dedicated tie-lines.     

Plant management of greenhouse roses. Lateral bud removal

Removal of sprouting lateral shoots in rose plants caused breaking of lateral accessory buds. The sprouting of accessory buds decreased toward cane base. Lateral-shoot removal also resulted in an increase in the leaf specific weight and chlorophyll content and an increase in the average root weight. The effect of de-shooting on the leaf abscission differed in canes of different positions on the plant.     

Effects of latex from "Amapazeiro"Parahancornia amapa (Apocynaceae) on blowfly Chrysomya megacephala (Diptera: Calliphoridae) post-embryonic development

Nowadays, insect control is usually carried out using chemical insecticides, but insect resistance and other negative side effects have prompted the search for alternatives. Biopesticides provide a positive alternative to synthetic pesticides because they have low impact on the environmental, low toxicity to humans and low costs among other advantages. This research was carried out to evaluate the activity of Parahancornia amapa (Huber) Ducke (Apocynaceae) lyophilized latex on the post embryonic development of Chrysomya megacephala (F.) (Diptera: Calliphoridae). Larvae treated with 1.0% latex showed a shorter post embryonic development period (larval, pupal and newly hatched larvae to adult); whereas larvae treated with 3.0% latex provoked a prolongation of these periods. Viability (53%) was also very low at the newly hatched larvae to adult period for larvae treated with 3.0% latex, indicating that latex from P. amapa at high concentrations could change C. megacephala post embryonic development.     

Targeting to porcine sialoadhesin receptor improves antigen presentation to T cells

Antibody-mediated targeting of antigen to specific antigen presenting cells (APC) receptors is an attractive strategy to enhance T cell immune responses to weak immunogenic antigens. Here, we describe the characterization of two monoclonal antibodies (mAb) against different epitopes of porcine sialoadhesin (Sn) and evaluate in vitro the potential of targeting this receptor for delivery of antigens to APC for T cell stimulation. The specificity of these mAb was determined by amino acid sequence analysis of peptides derived from the affinity purified antigen. Porcine Sn is expressed by macrophages present in the border between white and red pulp of the spleen and in the subcapsular sinus of lymph nodes, an appropriate location for trapping blood and lymph-borne antigens. It is also expressed by alveolar macrophages and monocyte-derived dendritic cells (MoDC). Blood monocytes are negative for this molecule, but its expression can be induced by treatment with IFN-a. MAb bound to Sn is rapidly endocytosed. MAb to sialoadhesin induced in vitro T cell proliferation at concentrations 100-fold lower than the non-targeting control mAb when using T lymphocytes from pigs immunized with mouse immunoglobulins as responder cells and IFN-a treated monocytes or MoDC as APC, suggesting a role of sialoadhesin in antigen uptake and/or delivery into the presentation pathway in APC.     

Relation between visitors’ behaviour and characteristics of green spaces in the city of Granada,south-eastern Spain

This paper examines the relation between visitor behaviour and certain features of a number of major green spaces in the city of Granada, south-eastern Spain, focussing on key urban, ecological and landscape-related issues. Information on user profiles and numbers, the various uses made of these areas, their design, plant species richness and local urban and sociological background, was collected by means of in situ observation in a total of ten urban green spaces with surface areas of over 5000 m². Findings indicated that these spaces were used largely for purposes directly related to well-being: recreational and sporting activities, socialising, or simply relaxing. Interestingly, the most common activities in each space were governed by features intrinsic to the space itself: accessibility, design, maintenance and plant richness and distribution, all of which affected the health-related attributes and aesthetic value of the space. The study also highlighted a number of serious deficiencies in certain green spaces, which will need to be addressed in future action plans and replanning projects as an essential step in ensuring that they meet the real needs and expectations of the target population. The information provided by this research may prove particularly valuable for improving the systemic functions of green spaces in Mediterranean cities sharing similar bioclimatic and sociological features, and for ensuring that they fulfil the role assigned to green spaces in sustainable cities.     

A new pathotype of<Emphasis Type="Italic">Pseudoperonospora cubensis</Emphasis> causing downy mildew in cucurbits in Israel

Downy mildew, incited by the comycetePseudoperonospora cubensis (Berk.et Curt.) Rost., was recorded in Israel during the years 1979–2001 on cucumber (Cucumis sativus) and melon (Cucumis melo) and classified as pathotype 3. In July 2002 severe outbreaks of downy mildew occurred on pumpkin (Cucurbita moschata) and summer squash (Cucurbita pepo subsp.pepo). Host range pathogenicity studies revealed high compatibility of the new population with cucumber, melon, pumpkin and summer squash but low compatibility with watermelon. This new population was therefore designated as pathotype 6. The possible origin of this new pathotype in Israel is discussed. http://www.phytoparasitica.org posting Oct. 9, 2003.     

Agriculture in the transition from a command to a market economy: the case of Latvia

The study presented is the result of a field survey conducted in Latvia in 1991. The brief of this research was to trace the role of the ‘private’ farm sector that has begun to emerge in the wake of the transition from a central-command to a market-oriented economy. Thus a look at the legislative acts embodying the agrarian reform is ccompanied by an analysis of the recent developments in local production systems. The study of ‘production systems’, or that part of economic analysis that comes under the rubric of ‘farm systems’, was employed here for the first time to analyze a Soviet-type economic system in transition. The first and second sections, which focus on the historical evolution of Latvia's agriculture and the economics underpinning it, range in compass from the ‘first’ agrarian reform to collectivization and on to the present situation. This is followed by a look at the current, or ‘third’, land reform initiative (section 3), particular emphasis being accorded the emergence of new production structures and the problems posed by the transformation of the old ones (sections 4 and 5). The next section includes a discussion of the links between the farms of the socialized sector and of the nascent private one (section 6). The concluding remarks provide a recapitulation of the study's main findings.