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Descriptors Used (descriptor + used)
Selected AbstractsInvertebrate community structure in streams of the Manawatu,Wanganui region, New Zealand: the roles of catchment versus reach scale influencesFRESHWATER BIOLOGY, Issue 8 2004Russell G. Death Summary 1. Invertebrate communities at 187 least impacted streams in the Manawatu,Wanganui region of New Zealand were sampled between February and May 2000 to investigate the relative influence of catchment and reach scale environmental influences on community structure. 2. Of the 138 biological (fish and periphyton), local habitat and catchment scale descriptors used to examine invertebrate community patterns, alkalinity and conductivity were the most consistently influential predictors. 3. Of the 52 geographical information system (GIS)-derived catchment variables (catchment geology, catchment land use, rainfall and topography) only per cent catchment in pasture, indigenous forest, coastal sand, crushed argillite and wind blown sand were associated with any measures of the invertebrate communities. 4. Grouping of communities based on GIS data in general, did not generate distinct community types. Groupings based on river catchment, conductivity and alkalinity however, did produce distinct communities. 5. Streams with very low alkalinity were dominated by Ephemeroptera, Plecoptera and Trichoptera that were gradually replaced by Mollusca, Crustacea and Chironomidae as alkalinity increases. 6. Habitat characteristics measured at the scale of the reach were more closely linked with measures of invertebrate community structure than any GIS derived variables or river classifications. [source] Richness and diversity of helminth communities in tropical freshwater fishes: empirical evidenceJOURNAL OF BIOGEOGRAPHY, Issue 4 2000Anindo Choudhury Abstract Aim Published information on the richness and diversity of helminth parasite communities in tropical freshwater fishes is reviewed in response to expectations of species-rich parasite communities in tropical regions. Location Areas covered include the tropics and some subtropical areas. In addition, the north temperate area of the nearctic zone is included for comparison. Methods Data from 159 communities in 118 species of tropical freshwater fish, summarized from 46 published studies, were used for this review. Parasite community descriptors used in the analyses included component community richness and calculated mean species richness. Data from 130 communities in 47 species of nearctic north temperate freshwater fish were summarized from 31 studies and used for comparison. Results The component helminth communities of many tropical freshwater fish are species-poor, and considerable proportions of fish from certain parts of the tropics, e.g. West African drainages, are uninfected or lightly infected. Mean helminth species richness was low and equaled or exceeded 2.0 in only 22 of 114 communities. No single group of helminths was identified as a dominant component of the fauna and species composition was variable among and within broader geographical areas. The richest enteric helminth assemblages were found in mochokid and clariid catfish with a mixed carnivorous diet, whereas algal feeders, herbivores and detritivores generally had species-poor gut helminth communities. Comparisons indicated that certain areas in the north temperate region had higher helminth species richness in fishes than areas in the tropics. Main conclusions Expectations of high species richness in helminth communities of tropical freshwater fishes are not fulfilled by the data. Direct comparisons of infracommunities and component communities in host species across widely separated phylogenetic and geographical lines are inappropriate. Examination of latitudinal differences in richness of monophyletic parasite groups or of compound communities may uncover patterns different from those found in this study. Richness of helminth communities may be ultimately determined not by the number of host species present but by the degree of divergence of host lineages and by their diversification modes. A phylogenetic framework for hosts and parasites will reveal if increased host species richness within host clades, when host speciation is accompanied by habitat or diet specialization, or both, leads to lower helminth diversity in host species by fragmentation of a core helminth fauna characteristic or specific of the larger host clade. This pattern may be analysed in the context of cospeciation and acquisition from other unrelated hosts (host-sharing or host-switching). [source] The training needs of health care support workers: results of a study of workers and their managersJOURNAL OF CLINICAL NURSING, Issue 12 2007Laurence G Moseley MA Aims and objectives., This study was designed to assess the training needs of health care support workers. In the past, opinions on the topic have been varied, but were rarely based on empirical evidence. Design and methods., The study was designed as a self-report questionnaire survey of health care support workers and their managers in six units in health and social care, using as its basis 32 descriptors from the NHS Knowledge and Skills Framework, levels 1 and 2. The achieved sample was 117, giving a 77% response rate. Results., Thirty-five per cent of respondents thought that health care support workers were ,unable' to perform six or more of the 32 descriptors used, whilst on the criterion of being ,less than able', the figure was 64%. Support workers and their managers agreed closely (rho = 0·8) on where the difficulties lay in achieving Knowledge and Skills Framework competencies. Those difficulties lay particularly in two areas: (1) biomedical/physiological knowledge and (2) data-handling. Conclusions., We concluded that the numbers in need of training were substantial and the areas of need were the two identified above. Relevance to clinical practice., The main implications for clinical practice are that (a) for those who supervise or mentor health care support workers, there should be a greater concentration on the more scientific areas of expertise and (b) a similar emphasis is needed for those who train mentors or supervisors. These implications will become more important over time as scientific knowledge about medicine and health care increases. [source] Antitumour activity and specificity as a function of substitutions in the lipophilic sector of helical lactoferrin-derived peptideJOURNAL OF PEPTIDE SCIENCE, Issue 5 2003Nannan Yang Abstract A peptide L5 (PAWRKAFRWAWRMLKKAA), derived from the N -terminal ,-helical region of bovine lactoferrin (LFB 14,31), that is highly active against several tumour cell lines was reported earlier. In this study, a number of L5 analogues were designed in order to investigate how subsequent replacements of the aromatic amino acids in L5 with three amino acids representing different structural parameters influenced antitumour activity and tumour cell specificity relative to normal human cells. The Trp residues were substituted by Lys, Ile or Ala, while the Phe residue was substituted with Ala. The resulting peptides were investigated for their activity against prokaryotic cells, four tumour cell lines, human lung fibroblasts and human erythrocytes. Most of the peptides were highly active against both E. coli and S. aureus. The peptides were more active against the tumour cell lines than against normal eukaryotic cells but the activity against normal fibroblasts varied more among the peptides than did their antitumour activities. The results revealed that aromatic residues located opposite the cationic sector in L5 were more critical for antitumour activity than were aromatic residues located adjacent to the cationic sector. The biological responses for the peptides against tumour cell lines, fibroblasts, S. aureus (but not E. coli), were highly correlated with the amino acid descriptors used in our QSAR model. The result obtained from the QSAR study identified specific structural features that were important for lytic activity and membrane specificity. Certain structural properties in positions 3, 9 and 11 were shown to be important for antitumour activity, while additional structural properties in position 7 were found to be important with respect to tumour cell specificity. This information may offer a possibility for de novo design of an antitumour peptide with an improved therapeutic index. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd. [source] Toxicity Mode-of-action: Discrimination via Infrared Spectra And Eigenvalues of the Modified Adjacency MatrixMOLECULAR INFORMATICS, Issue 2 2003Anna Pino Abstract Aquatic toxicity can be partitioned into a number of mechanisms of action, the allocation of a given chemical to its particular mode being of fundamental importance for the toxicological risk assessment. We investigated the possibility to automatically allocate each chemical to its putative aquatic toxicity mode-of-action on the basis of the sole chemical physical information. In this paper, we refer to the four mode-of-action classes defined in Hermens' laboratory [1, 2]; the chemical descriptors used were the Infrared spectra and the Burden's Modified Adjacency Matrix Eigenvalues. At odds with Infrared spectrum, the Eigenvalues were able to allocate the chemicals into the different mechanism of action classes via a nonlinear discrimination method (K-nearest neighbours classifier). [source] Subjective pain experience of people with chronic back painPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 4 2000Professor Lorraine H De Souza Chair of Rehabilitation Abstract Background and Purpose Studies into the effect of pain experience on those who have it have largely focused on the views and interpretations of researchers gained by the use of assessment tools aimed at measuring pain. The purpose of this study was to explore and describe pain, as experienced by those with chronic back pain, and to document ,insider' accounts of how pain is perceived and understood by those who have it. Method Unstructured interviews using the framework approach. Subjects were sampled for age, sex, ethnicity and occupation, from new referrals with back pain to a rheumatology outpatient clinic. Eleven subjects (5 M; 6 F) agreed to be interviewed. Interviews were unstructured, but followed a topic guide. Subjects were interviewed in English (nine) or their preferred language (two). Tape-recordings of interviews were transcribed verbatim and read in depth twice to identify the topics or concepts. Data were extracted in the form of words and phrases by use of thematic content analysis. The themes were pain description and amount of pain. An independent researcher reviewed the data and confirmed or contended the analysis. Results All subjects, except one, provided descriptors of the quality of their pain. The use of simile was common to emphasize both what the pain was, and what it was not. Five subjects expressed a loss of words in trying to describe their pain. Only 13 of 29 different pain descriptors used were commensurate with those in the McGill Pain Questionnaire (Melzack, 1983). Subjects had great difficulty quantifying their pain intensity. Several explained how the pain fluctuated, thus, quantifying pain at one point in time was problematic. Only one subject offered a numerical description of pain intensity. Conclusions Subjects provided graphic and in-depth descriptions of their pain experience, but these bore little resemblance to commonly used assessment tools. The findings challenge the appropriateness of such formal instruments. Copyright © 2000 Whurr Publishers Ltd. [source] | |||||||||||||