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[Mental retardation: social supports for people with metal retardation from aspects of individual and family life-cycle: introductory remarks] [In Process Citation]

In this symposium, the terminology and difinition of mental retardation were discussed. We examined theories and practices of social services, as well as policies for people with mental retardation from the aspects of individual and family life-cycle. Panelists at the invitation of this symposium were experts on this subject. They proposed new theories and made practical comments. The key words include the change of medical to social model; early diagnosis and intervention; medical care for children with severe disabilities at school-life and support for their family; career education and transition services; support with residential facilities and community-based approach; and empowerment of people with developmental disabilities.

Journal Article↗

Requirement of sterols in the life cycle of the nematode Caenorhabditis elegans.

The nematode Caenorhabditis elegans represents an excellent model for studying many aspects of sterol function on the level of a whole organism. Recent studies show that especially two processes in the life cycle of the worm, dauer larva formation and molting, depend on sterols. In both cases, cholesterol or its derivatives seem to act as hormones rather than being structural components of the membrane. Investigations on C. elegans could provide information on the etiology of human diseases that display defects in the transport or metabolism of sterols.

Animals↗

Ela 1.0--a framework for life-cycle impact assessment developed by the Fraunhofer-Gesellschaft. Part A: The conceptual framework.

The Fraunhofer-Gesellschaft has sponsored the development of a conceptual and flexible, computer aided tool to perform the impact assessment within LCA (life cycle assessment) for technical products and processes. The developed general framework "Ela 1.0" (environmental loads analysis) consists of four elements: the selection of appropriate impact categories, the categorization of emissions and wastes leaving the systems as well as of resource and energy consumption, the characterization and an analysis of the results of the impact assessment. The latter compares the product-based emissions with the total of emissions of a region such as Germany, the EU or OECD countries. The framework Ela 1.0 considers the environmental categories: global warming, ozone depletion, resource and energy consumption, wastes, eutrophication (including COD and BOD as measured parameters), acidification, ecotoxicity, ozone formation and human toxicity. The latter categories are handled by listing of precursors for ozone formation, and by listing of emissions scored according to their human hazard potential. The options, possibilities and limitations of the conceptual framework are presented in part A of a series of publications.

Acid Rain↗

Life cycle of Tritrichomonas muris.

Morphological and physiological studies were carried out on a flagellate, Tritrichomonas muris, in golden hamsters. The experiments confirmed that a pseudocyst and an intermediate form exist in addition to the trophozoite in the life cycle; furthermore it was shown that the pseudocyst was the infective stage, and that a true cyst did not occur.

Animals↗

Phyto-oestrogens through the life cycle.

The growing interest in the role of phyto-oestrogens in human health has prompted scientists to evaluate the risk : benefit which would result from consuming high levels of these compounds at different stages of the life cycle. These compounds have been shown to exert a wide range of hormonal and non-hormonal activities in animals and in vitro, and these activities suggest plausible mechanisms for potential health effects in human subjects consuming phyto-oestrogen-rich diets. In addition, experimental and epidemiological data are available supporting the concept that phyto-oestrogen-rich diets exert physiological effects in vivo; however, their relative importance to human health remains to be elucidated. Our understanding of factors involved in their absorption and metabolism, including the role of intestinal microflora, is limited, and these factors together with dose-related effects may well be important in determining clinical efficacy.

Adult↗

Simulation of life-cycle efficiency of lamb and wool production for genetic levels of component traits and alternative management options.

A deterministic computer model was used to predict effects of genetic improvements in performance and of management options on life-cycle flock TDN input per unit of empty body weight (EBW) or carcass lean (CLN) equivalent value of market lamb, cull ewe, and wool output from a pure breeding system of sheep production for sheep fed to maintain normal weight. Relative values per kilogram for market lambs, cull ewes, and clean wool were 1 to .33 to 2.04 in lamb empty body equivalent, but 1 to .33 to 1 in lamb carcass lean equivalent. A 10% increase in lamb viability improved TDN/EBW or CLN by -15 to -20% for high to low lambing rates. Corresponding smaller gains were -7 to -11% for fertility, -3 to -13% for lambing rate, -1 to -3% for wool growth rate, -1 to -5% for milk production without creep feeding, -2 to -1% for mature size to about 70 kg, and -.6 to -.9% for precocity of fertility. Increasing leanness 10% improved TDN/CLN by -3 to -1% but increased TDN/EBW 3% because of higher maintenance requirements of leaner sheep. Higher protein requirements for increased lambing rate, milk production or leanness, or greater increases in non-feed than in feed costs, would mean only slightly less reduction of TDN/output than shown. Creep feeding was beneficial only for prolific, low-milking stock. Flushing reduced adverse effects of restricted feeding. Different values for wool vs meat or for costs of feed vs non-feed inputs would change results. These estimates for relative economic importance of traits apply to derivation of optimum criteria for selection among breeds or crosses, or within-breeds used in rotation crossbreeding, but would differ for specialized terminal-sire or maternal breed roles.

Animal Husbandry↗

A life-cycle model of organizational federations: the case of hospitals.

Hospital federations are a form of multiorganizational collaboration in which a management group coordinates and directs the activities of three or more organizations. This paper introduces a life-cycle model of federations that focuses on factors that influence the transition from one stage to another.

Hospital Shared Services↗

[Differentiation of closely related species Hyalomma anatolicum and H. excavatum (Acari: Ixodidae) based on a study of all life cycle stages, throughout entire geographical range].

Species status is stated for Hyalomma anatolicum and H. excavatum, based on numerous material from the territory of their distribution. The differentiation of species is recovered for all stages of the life cycle. Diagnosis of Hyalomma anatolicum. Female: small tick--length of scutum commonly less than 2 mm; width of scutum commonly less than 1.9 mm; color of scutum, gnathosoma and coxae light, yellowish- or reddish-brown; whitish enameled pigment on scutum absent; posterolateral ledges of scutum weakly expressed or absent; cervical and lateral grooves more shallow (than in H. excavatum) (fig. 1); setae of scutum, alloscutum, sternal setae and ventromedian setae of second article of palpae more tapering to the apex, narrow rounded or acute (fig. 2, 1, 2, 5, 8). Male: small tick--length of conscutum, as a rule, less than 4 mm; width of scutum, as a rule, less than 2.3 mm; shape of conscutum marrow oval (fig. 3), widest in the midlevel; color of conscutum, anal shields, gnathosoma and coxae light, yellowish- or reddish-brown; whitish enameled pigment on conscutum absent; caudal depression with less dense and more large punctuations (than in H. excavatum); ridges lateral to caudal field less high and sharp (than in H. excavatum); posteromedian groove separated from parma by contiguous punctuations or smooth non high area; setae of conscutum conus-like, more sharpening (fig. 4, 1-3); posterior dorsal margin of gnathosoma straight or slightly concave (fig. 4, 8); segments of leg IV not swallowed. Nymph: large tick (see description). Scutum more narrow. Dorsal tale of spiracular plates clear expressed, marginal perforations distant from margin of spiracular plates at the base of tale (fig. 5, 3); anterolateral side of basis capituli approximately equal to half of gnathosoma width; ventrally lateral projections of gnathosoma situated in posterior half of capitulum base (fig. 5, 4, 5). Hypostome more longer and narrow (fig. 5, 5). Larva: large tick (see description). Diagnosis of Hyalomma excavatum. Female: large tick--length of scutum commonly more than 2 mm; width of scutum commonly more than 1.9 mm; color of scutum, gnathosoma and coxae dark, reddish- or black-brown; whitish enameled pigment commonly present; posterolateral ledges of scutum clearly expressed; cervical and lateral grooves more dipper (than in H. anatolicum) (fig. 7). Setae of scutum, alloscutum, sternal setae and ventromedian setae of second article of palpae more stick-like, more widely obtuse (fig. 8, 1-5). Male: large tick--length of conscutum more than 4 mm; width of scutum more than 2.3 mm; shape of conscutum wide oval (fig. 9), widest in posterior half of length; color of conscutum, anal shields, gnathosoma and coxae dark, reddish- or black-brown; whitish enameled pigment often present; caudal depression with more dense and more small punctuations (than in H. anatolicum); ridges lateral to caudal field more high and sharp (than in H. anatolicum); posteromedian groove separated from parma by strong elevations fused with paraparmal festoons; setae of conscutum more obtuse, often stick-like (fig. 10, 1, 2); posterior dorsal margin of gnathosoma straight or lightly concave. (fig. 10, 3); segments of leg IV swallowed. Nymph: small tick (see description). Scutum more wide. Dorsal tale of spiracular plates weakly expressed, marginal perforations not distant from margin of spiracular plates at the base of tale (fig. 11, 3); anterolateral side of basis capituli clearly shorter than half of gnathosoma width; ventrally lateral projections situated in the middle of or anterior half of capitulum base (fig. 11, 4, 5). Hypostome more shorter and wider (fig. 5, 5). Larva: small tick (see description). Established taxonomical independence of H. anatolicum and H. excavatum is confirmed by several criteria: external morphology (see diagnoses); morphometrical data (see diagnoses and fig. 12, 13); size inversion: larva and nymph of H. anatolicum are large, but females and males are small; while H. excavatum vise versa--larva and nymph are small, but adults--large; host specialization of immature stages: larvae and nymphs of H. anatolicum, as rule, parasitize larger mammals (cattle, camels), while immature stages of H. excavatum parasitize smaller mammals (rodents, hares); presence of sympatry areas: almost entire area of H. excavatum include in area of H. anatolicum and cattle help to mix its populations.

Africa↗

[Cestode adaptation to life cycles].

There are two groups of cestode adaptations. One of them makes it possible for particular developmental stages to be adapted to their particular environment (including second order environment). The second one involves passing through the entire life circle: transition from one environment to another, releasing from protective shells, host intrusion, population density regulation at different developmental stages. Spectrum of adaptive reactions on the life cycles is determined by peculiarities of parasite systems.

Adaptation, Physiological↗

Trypanosoma congolense: developmental regulation of protein kinases and tyrosine phosphorylation during the life cycle.

In higher eukaryotes, key steps in the control of growth and proliferation are regulated by protein phosphorylation. However, little is known about the role of protein phosphorylation in the developmental cycles of pathogenic protozoa. In Trypanosoma brucei, only the bloodform and procyclic form stages can be obtained in sufficient numbers for biochemical analyses. However, the entire life cycle of Trypanosoma congolense can be generated in vitro, providing sufficient material for analyses of the different developmental stages. The studies reported here provide a series of snapshots documenting the activity of a number of protein serine/threonine kinases and the pattern of tyrosine-phosphorylated proteins throughout the T. congolense developmental cycle. Metacyclic forms and mammalian bloodforms showed similar profiles of protein kinase activity, as did procyclic forms and epimastigotes. Most tyrosine-phosphorylated proteins were shared between all developmental stages, with the exception of a 100-kDa metacyclic-specific species. The developmental changes in molecules involved in protein phosphorylation in the different developmental stages support the concept that changes in protein phosphorylation networks are important correlates of the developmental process in African trypanosomes.

Animals↗

Life cycle approach to child and adolescent health.

Young people are our human capital for the future, therefore child and adolescent health has attracted considerable political and professional attention in recent years. Health is indivisible, requires holistic approach throughout the individual's life. Healthy outcome at one point in the life cycle, provides a positive determinant for health elsewhere in the cycle. Health and development of the 0-19 age group links intimately, at both ends of the range, with reproductive health. Health during childhood is in part determined by the health of the mother, and affected also by factors such as the nutrition of adolescent girls and the avoidance of early pregnancy. These factors, in turn, are influenced by healthy growth and development in childhood. The paper presents main environmental and socio-cultural challenges for each of the stages of child and adolescent life. Main challenge described are: unsafe abortion, malnutrition, anaemia, malformations, and infections during pregnancy; low birth weight, asphyxia, hypothermia, infection, failure to initiate early and full breastfeeding in the neonatal period; poor nutrition, growth and development, frequent illnesses, injury, abuse and neglect in the early childhood; poor nutrition, growth and development, injury, abuse, neglect, and helminth infections in the early school age; poor nutrition, poor development, chronic conditions, mental disorders, injury, drug abuse, and violence in the adolescence. Both, prevention of ill health and care for illnesses are important at all times but the balance between them shifts over time during the childhood and adolescence. Main actions needed to meet the child and adolescent needs are presented as well.

Adolescent↗

Energy and emission benefits of alternative transportation liquid fuels derived from switchgrass: a fuel life cycle assessment.

We conducted a mobility chains, or well-to-wheels (WTW), analysis to assess the energy and emission benefits of cellulosic biomass for the U.S. transportation sector in the years 2015-2030. We estimated the life-cycle energy consumption and emissions associated with biofuel production and use in light-duty vehicle (LDV) technologies by using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model. Analysis of biofuel production was based on ASPEN Plus model simulation of an advanced fermentation process to produce fuel ethanol/protein, a thermochemical process to produce Fischer-Tropsch diesel (FTD) and dimethyl ether (DME), and a combined heat and power plant to co-produce steam and electricity. Our study revealed that cellulosic biofuels as E85 (mixture of 85% ethanol and 15% gasoline by volume), FTD, and DME offer substantial savings in petroleum (66-93%) and fossil energy (65-88%) consumption on a per-mile basis. Decreased fossil fuel use translates to 82-87% reductions in greenhouse gas emissions across all unblended cellulosic biofuels. In urban areas, our study shows net reductions for almost all criteria pollutants, with the exception of carbon monoxide (unchanged), for each of the biofuel production option examined. Conventional and hybrid electric vehicles, when fueled with E85, could reduce total sulfur oxide (SO(x)) emissions to 39-43% of those generated by vehicles fueled with gasoline. By using bio-FTD and bio-DME in place of diesel, SO(x) emissions are reduced to 46-58% of those generated by diesel-fueled vehicles. Six different fuel production options were compared. This study strongly suggests that integrated heat and power co-generation by means of gas turbine combined cycle is a crucial factor in the energy savings and emission reductions.

Air Pollution↗

Life- cycle assessment in pesticide product development: methods and case study on two plant-growth regulators from different product generations.

Environmental assessments in pesticide product development are generally restricted to plant uptake and emissions of active ingredients. Life-cycle assessment (LCA) enables a more comprehensive evaluation by additionally assessing the impacts of pesticide production and application (e.g. tractor operations). The use of LCA in the product development of pesticides, in addition to the methods commonly applied, is therefore advisable. In this paper a procedure for conducting LCA in early phases of product development is proposed. In a case study, two plant-growth regulators from different product generations were compared regarding their application in intensive production of winter wheat. The results showed thatthe reduced emissions from active ingredients of the newer pesticide were compensated by higher impacts from the production process. The authors draw the conclusion that it is important to consider environmental objectives in the procurement of precursors, in addition to the classical goals of increasing the efficacy and reducing the nontarget effects of pesticides. Moreover, the case study showed that decisions based on uncertain results in early stages of product development may need to be revised in later stages, e.g. based on investigations of pesticides' effects on crop yield.

Chlormequat↗

Evidence for a complex life cycle and endospore formation in the attached, filamentous, segmented bacterium from murine ileum.

Light and electron microscope observations showed that the filamentous, segmented bacterium commonly found attached to the ileal epithelium of rats and mice undergoes a complex life cycle. Filaments comprising up to 90 segments were attached to the microvillous border of absorptive epithelial cells by a specialized terminal holdfast segment. Starting at the free end of the filament and progressing toward the attached end, undifferentiated segments were converted into reproductive or mother segments. Within each mother cell two new holdfast segments developed. As the holdfasts matured, their mother cells degenerated and released them into the intervillar space where they attached, grew, and divided to produce new segmented filaments. Alternately, in some filaments, newly formed but not yet released holdfasts were converted into endospores, which were released in the same manner as holdfasts, presumably to spread the bacterial colony to other members of the rodent population.

Animals↗

Medical facility life cycle investment strategy.

This document discusses a health care investment strategy developed by the military. It is based from a survey conducted of both private and military facilities. The document provides techniques to help determine a medical facility's life cycle cost.

Benchmarking↗

Protein synthetic patterns during the asexual life cycle of Volvox carteri.

The polypeptide labeling patterns of somatic cells, gonidia (asexual reproductive cells), embryos, and juvenile spheroids of Volvox carteri cultures synchronized by a light/dark cycle were studied as a function of developmental stage and incubation condition. Specimens were exposed to 35SO=4 for 1-hr periods at selected intervals throughout the asexual life cycle; proteins were then extracted and analyzed by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by fluorography. Although sulfation accounts for more than half the 35S incorporated, the conditions of extraction and electrophoresis employed resulted in exclusion of most sulfated products and inclusion of nearly all products bearing incorporated sulfur amino acids in the electrophoretic analysis. Hence SDS-PAGE profiles reflect relative rates of synthesis of major polypeptides. The first phase of these studies involved examination of stage-specific differences in protein synthetic patterns. Because a single developmental stage exhibits different protein synthetic patterns in light and darkness, detailed developmental comparisons were made only on organisms or cells exposed to label in the light. They yielded the following results: Shortly after the completion of embryogenesis (while all cells are still linked by numerous cytoplasmic bridges) presumptive somatic cells and gonidia exhibit a nearly identical pattern of labeling of the major polypeptides. In just a few hours, however, as cytoplasmic bridges begin to break down, the synthetic patterns of the two cell types begin to diverge; with passing time this divergence becomes progressively greater. By the time gonidia are mature, the patterns of labeling of major polypeptides by somatic cells and gonidia exhibit far more differences than similarities. Embryos derived from these mature gonidia then exhibit numerous, reproducible, stage-specific changes in polypeptide labeling throughout embryogenesis. However, two glycoproteins that previous authors implicated in the control of the differentiative cleavage division are here shown to be labeled in the parental somatic cells, not in the embryos as was previously supposed; hence a central role for them in embryonic development seems highly unlikely. In the second phase of this study the effects of light on protein synthetic patterns of organisms at selected developmental stages were analyzed. At all stages marked, rapid, reversible changes in the pattern of labeling of major polypeptides occur when cultures are transferred from light to dark or vice versa, but these changes are most marked in juvenile spheroids at the end of the dark period during which they had completed their embryogenesis. Some, but by no means all, of the changes induced by light can be attributed to stimulated synthesis of chloroplast proteins, on both chloroplast and cytosol ribosomes. The proteins made at the beginning of one light period are not identical to those made at the end of the preceding light period...

Animals↗

Varied persistent life cycles of Borna disease virus in a human oligodendroglioma cell line.

Borna disease virus (BDV) establishes a persistent infection in the central nervous system of vertebrate animal species as well as in tissue cultures. In an attempt to characterize the life cycle of BDV in persistently infected cultured cells, we developed 30 clones by single-cell cloning from a human oligodendroglioma (OL) cell line after infection with BDV. According to the percentage of cells expressing the BDV major proteins, p40 (nucleoprotein) and p24 (phosphoprotein), the clones were classified into two types: type I (>20%) and type II (<20%). mRNAs corresponding to both proteins were detected by in situ hybridization (ISH) in a percentage of cells consistent with that for the protein expression in the two types. Surprisingly, ISH for the detection of the genomic RNA, mainly in type II, revealed a significantly larger cell population harboring the genomic RNA than that with the protein as well as the mRNA expression. By recloning from type II primary cell clones, the same phenotype was confirmed in the secondary cell clones obtained: i.e., low percentage of protein-positive cells and higher percentage of cells harboring the genomic RNA. After nerve growth factor treatment, the two types of clones showed increases in the percentage of cells expressing BDV-specific proteins that reached 80% in type II clones, in addition to increased expression levels per cell. Such enhancement might have been mediated by the activation of the mitogen-activated protein kinase in the clones as revealed by the detection of activated ERK1/2. Thus, our findings show that BDV may have established a persistent infection at low levels of viral expression in OL cells with the possibility of a latent infection.

Borna disease virus↗