219 resultados para living condition


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Available primary structural information suggests that the FMRFamide-related peptides (FaRPs) from parasitic and free-living nematodes are different, and that free-living forms may not represent appropriate models for the study of the neurochemistry of parasitic forms in the laboratory. However, here we report the isolation and unequivocal identification of AF2 (originally isolated from the parasite, Ascaris suum) from acidified alcoholic extracts of the free-living species, Panagrellus redivivus. While reverse-phase HPLC analysis of extracts revealed FMRFamide-immunoreactivity to be highly heterogeneous, AF2 was the predominant FMRFamide-immunoreactive peptide present (at least 26 pmol/g wet weight of worms). This peptide was also the major immunoreactant identified by an antiserum raised to the conserved C-terminal hexapeptide amide of mammalian pancreatic polypeptide (PP), which has been used previously to isolate neuropeptide F (NPF). These observations were confirmed by radioimmunoassay and chromatographic fractionation of an acidified alcoholic extract of A. suum heads. The FMRFamide-related peptides present in a nematode extract may be highly dependent on the extraction medium employed, and these data would suggest that this complement of neuropeptides may not be as different between parasitic and free-living nematodes as initial studies have suggested. Finally, all of the evidence suggests that NPF is not present in nematodes and that the PP-immunoreactant previously demonstrated immunochemically is probably AF2.

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In nematodes, FMRFamide-related peptides (FaRPs) have been structurally characterised from the parasite, Ascaris suum, and from two free-living species, Panagrellus redivivus and Caenorhabditis elegans. While both FaRPs isolated from P. redivivus (PF1 and PF2) have been identified in C. elegans the two heptapeptides isolated from A. suum (AF1 and AF2) have until recently been considered unique to this parasitic species. We have recently isolated AF2 from P. redivivus and, during this study, an additional novel heptapeptide amide, Lys-Ser-Ala-Tyr-Met-Arg-Phe amide (KSAYMRFamide), was structurally characterised. A synthetic replicate of this peptide induced a rapid concentration-dependent muscle tension increase in an isolated A. suum somatic muscle preparation, with a threshold of approximately 0.1 mu M. These data suggest that the complement of FaRPs in parasitic and free-living nematodes may not be as radically different as preliminary studies would suggest, and that the absence of AF1, AF2 and KSAYMRFamide on the C. elegans FMRFamide-related peptide gene (flp-1) may imply the presence of at least two different FaRP genes in nematodes. (C) 1994 Academic Press, Inc.

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In attempting to expand the vocabulary of urban description and understanding, and to offer a new composite conceptual framework for a more integrated urban planning and policy, this essay addresses the informal, contested, and anchored dimensions of the urban in turn; second, it seeks to increasingly link the three within the new global context; and finally, it attempts to draw these strands together in a proposed reconceptualization of the contemporary city within a world where the global is urbanizing and the urban is globalizing.

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The concept of exospace, as an alternative liveable structure, is discussed in this article to improve our comprehension of architectural space. Exospace is a man-made space designed for living beyond Earth’s atmosphere. Humankind has developed outerspace technologies to build the International Space Station as a significant experiment in exospace design. The ISS is a new building type for scientific experiments and for testing human existence in outerspace.

A fictional example of exospace, on the other hand, is Discovery 1 spaceship in Stanley Kubrick’s legendary science fiction film 2001: A Space Odyssey (1968). It is a ship travelling to Jupiter with a crew of five astronauts and HAL9000, the artificial intelligence controlling the ship. I will first discuss the ISS, and the space stations built before, from a spatial point of view. A spatial study of Discovery 1 will follow. Finally, through an understanding of exospace, I will return to architectural space with a critical appraisal. The comparison of architectural space with exospace will add to the discussion of space theories from a technological approach.

Exospace creates an alternative reality to architectural space. Architects cannot consider exospaces without comparing them with the spaces they design on Earth. The different context of outerspace shows that a work of terrestrial architecture is very much dependent on its context. A building is not an ‘object’ that can be located anywhere; it is designed for its site. Architectural space is a real, material, continuous, static and extroverted habitable space designed for and used in the specific physical context of Earth. The existence of exospace in science opens a new discussion in architectural theory, both terrestrial and extraterrestrial.

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This paper presents the design and implementation of a novel optical fiber temperature compensated relative humidity (RH) sensor device, based on fiber Bragg gratings (FBGs) and developed specifically for monitoring water ingress leading to the deterioration of building stone. The performance of the sensor thus created, together with that of conventional sensors, was first assessed in the laboratory where they were characterized under experimental conditions of controlled wetting and drying cycles of limestone blocks, before being employed “in-the-field” to monitor actual building stone in a specially built wall. Although a new construction, this was built specifically using conservation methods similar to those employed in past centuries, to allow an accurate simulation of processes occurring with wetting and drying in the historic walls in the University of Oxford.

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This paper presents an innovative sensor system, created specifically for new civil engineering structural monitoring applications, allowing specially packaged fiber grating-based sensors to be used in harsh, in-the-field measurement conditions for accurate strain measurement with full temperature compensation. The sensor consists of two fiber Bragg gratings that are protected within a polypropylene package, with one of the fiber gratings isolated from the influence of strain and thus responding only to temperature variations, while the other is sensitive to both strain and temperature. To achieve this, the temperature-monitoring fiber grating is slightly bent and enclosed in a metal envelope to isolate it effectively from the strain. Through an appropriate calibration process, both the strain and temperature coefficients of each individual grating component when incorporated in the sensor system can be thus obtained. By using these calibrated coefficients in the operation of the sensor, both strain and temperature can be accurately determined. The specific application for which these sensors have been designed is seen when installed on an innovative small-scale flexi-arch bridge where they are used for real-time strain measurements during the critical installation stage (lifting) and loading. These sensors have demonstrated enhanced resilience when embedded in or surface-mounted on such concrete structures, providing accurate and consistent strain measurements not only during installation but subsequently during use. This offers an inexpensive and highly effective monitoring system tailored for the new, rapid method of the installation of small-scale bridges for a variety of civil engineering applications.

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The influence of both compressive and tensile epitaxial strain along with the electrical boundary conditions on the ferroelastic and ferroelectric domain patterns of bismuth ferrite films was studied. BiFeO3 films were grown on SrTiO3(001), DyScO3(110), GdScO3(110), and SmScO3(110) substrates to investigate the effect of room temperature in-plane strain ranging from -1.4% to +0.75%. Piezoresponse force microscopy, transmission electron microscopy, x-ray diffraction measurements, and ferroelectric polarization measurements were performed to study the properties of the films. We show that BiFeO3 films with and without SrRuO3 bottom electrode have different growth mechanisms and that in both cases reduction of the domain variants is possible. Without SrRuO3, stripe domains with reduced variants are formed on all rare earth scandate substrates because of their monoclinic symmetry. In addition, tensile strained films exhibit a rotation of the unit cell with increasing film thickness. On the other side, the presence of SrRuO3 promotes step flow growth of BiFeO3. In case of vicinal SrTiO3 and DyScO3 substrates with high quality SrRuO3 bottom electrode and a low miscut angle of approximate to 0.15 degrees we observed suppression of the formation of certain domain variants. The quite large in-plane misfit of SrRuO3 with GdScO3 and SmScO3 prevents the growth of high quality SrRuO3 films and subsequent domain variants reduction in BiFeO3 on these substrates, when SrRuO3 is used as a bottom electrode.

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Members of the taxonomically diverse Burkholderia cepacia complex have become a major health risk for patients with cystic fibrosis (CF). Although patient-to-patient transmission of B. cepacia strains has been well-documented, very little is known about possible vehicles of transmission and reservoirs for these micro-organisms. In this work, it is shown that strains of the B. cepacia complex can survive within different isolates of the genus Acanthamoeba. Trophozoites containing bacteria developed profuse cytoplasmic vacuolization. Vacuolization was not detected in trophozoites infected with live Escherichia coli or heat-killed B. cepacia, or by incubation of trophozoites with filter-sterilized culture supernatants, indicating that metabolically active intracellular bacteria are required for the formation of vacuoles. Experiments with two different B. cepacia strains and two different Acanthamoeba isolates revealed that bacteria display a low level of intracellular replication approximately 72-96 h following infection. In contrast, extracellular bacteria multiplied efficiently on by-products released by amoebae. The findings suggest that amoebae may be a reservoir for B. cepacia and possibly a vehicle for transmission of this opportunistic pathogen among CF patients.

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Based on a survey of 711 children in Northern Ireland, this paper explores a range of aspects of experiences of belonging and exclusion in relation to school among three main minority ethnic groups: Irish Traveller, Chinese/Asian and European Migrant children. The study examines variations between each group and how they compare to the White settled population. The findings indicate that all three groups experience lower levels of belonging and higher levels of exclusion compared to their White, settled Northern Irish peers. The experiences of Irish Traveller children were the most negative. The article adds to the dearth of data on minority ethnic children living in mainly white regions in the UK and Ireland. It argues for the need to move beyond achievement gaps in assessing minority ethnic children’s differential experiences in education and highlights the potential of belongingness as a concept for the further study of differential patterns of need and processes of inclusion.

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Within the health and social care sector in the United Kingdom, the
management of death and bereavement has become increasingly
challenging. This service evaluation sought to explore the bereavement
care offered to individuals living in one Health and Social Care
Trust catchment area of Northern Ireland. Qualitative interviews
were conducted with key government and voluntary agency staff.
The findings indicated that much of the bereavement provision is
based on the interest and initiative of individual staff members, with
few processes to assess the level of bereavement care needed and those
best skilled to provide it. Recommendations are made for a bereavement
care strategy that outlines a bereavement needs assessment process,
identifying the scope of interventions and protocols for practice.