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Comparable Samples (comparable + sample)
Selected AbstractsBone tissue engineering in a critical size defect compared to ectopic implantations in the goatJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2004Moyo C. Kruyt Abstract Since the application of the autologous bone graft, the need for an alternative has been recognized. Tissue engineering (TE) of bone by combining bone marrow stromal cells (BMSCs) with a porous scaffold, is considered a promising technique. In this study we investigated the potential of tissue engineered bone to heal a critical sized defect in the goat. Orthotopic bone formation was compared to ectopic bone formation in comparable constructs. TE constructs were prepared from goat BMSCs and porous biphasic calcium phosphate ceramic scaffolds. These constructs and scaffolds without cells were implanted paired in critical sized iliac wing defects. Comparable samples were implanted intramuscularly. After 9 (n = 7) and 12 (n = 8) weeks implantation, the samples were analyzed histomorphometrically. After 9-weeks implantation in the iliac wing defect, significantly more bone apposition was found in the TE condition. After 12 weeks, the defects were almost completely filled with bone, but no significant advantage of TE was determined anymore. This contrasted with the intramuscular samples where TE implants showed significantly more bone at both time points. In conclusion, bone TE is feasible in critical sized defects. However, when appropriate osteoconductive/inductive materials are applied the effect of cell seeding may be temporary. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Occupational stress in (inter)action: the interplay between job demands and job resourcesJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 5 2005Natasja van Vegchel The present study addresses theoretical issues involving different interaction effects between job demands and job resources, accompanied by a thorough empirical test of interaction terms in the demand,control (DC) model and the effort,reward imbalance (ERI) model in relation to employee health and well-being (i.e., exhaustion, psychosomatic health complaints, company-registered sickness absence). Neither the DC model nor the ERI model gives a clear theoretical rationale or preference for a particular interaction term. Hierarchical regression analyses were conducted among 405 nursing home employees and cross-validated in a comparable sample (N,=,471). Results including cross-validation showed that only a multiplicative interaction term yielded consistent results for both the DC model and the ERI model. Theoretical as well as empirical results argue for a multiplicative interaction term to test the DC model and the ERI model. Future job stress research may benefit from the idea that there should be a theoretical preference for any interaction form, either in the DC model or in the ERI model. However, more research on interactions is needed to address this topic adequately. Copyright © 2005 John Wiley & Sons, Ltd. [source] Lyman break galaxies and the star formation rate of the Universe at z, 6MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2003Elizabeth R. Stanway ABSTRACT We determine the space density of UV-luminous starburst galaxies at z, 6 using deep HST ACS SDSS- i, (F775W) and SDSS- z, (F850LP) and VLT ISAAC J and Ks band imaging of the Chandra Deep Field South. We find eight galaxies and one star with (i,,z,) > 1.5 to a depth of z,AB= 25.6 (an 8, detection in each of the 3 available ACS epochs). This corresponds to an unobscured star formation rate of ,15 h,270 M, yr,1 at z= 5.9, equivalent to L* for the Lyman-break population at z= 3,4 (,,= 0.7, ,M= 0.3). We are sensitive to star-forming galaxies at 5.6 ,z, 7.0 with an effective comoving volume of ,1.8 × 105h,370 Mpc3 after accounting for incompleteness at the higher redshifts due to luminosity bias. This volume should encompass the primeval subgalactic-scale fragments of the progenitors of about a thousand L* galaxies at the current epoch. We determine a volume-averaged global star formation rate of (6.7 ± 2.7) × 10,4h70 M, yr,1 Mpc,3 at z, 6 from rest-frame UV selected starbursts at the bright end of the luminosity function: this is a lower limit because of dust obscuration and galaxies below our sensitivity limit. This measurement shows that at z, 6 the star formation density at the bright end is a factor of ,6 times less than that determined by Steidel et al. for a comparable sample of UV-selected galaxies at z= 3,4, and so extends our knowledge of the star formation history of the Universe to earlier times than previous work and into the epoch where reionization may have occurred. [source] Interrelating within the families of young psychotherapy outpatientsCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 3 2009Argyroula E. Kalaitzaki Interrelating is a combination of relating to and being related to by another. The Couple's Relating to Each Other Questionnaires (CREOQ) and the Family Members Interrelating Questionnaires (FMIQ) measure negative forms of both self and other relating, across a close/distant and an upper/lower axis. These were used to measure the interrelating between the parents of young adults, and between young adults and their parents, in a sample of young, Greek, psychotherapy outpatients and a comparable sample of non- patients. In a proportion of both samples, the interrelating of the young adults was compared with that of a well sibling. The patients' parents were significantly more distant towards each other than those of the non-patients. The interrelating between the patients and their parents was markedly worse than that between the non-patients and their parents. It was also markedly worse between the patients and their parents than between the siblings and their parents.,Copyright © 2009 John Wiley & Sons, Ltd. [source] The effect of stopping smoking on perceived stress levelsADDICTION, Issue 8 2010Peter Hajek ABSTRACT Aims Many smokers believe that smoking helps them to cope with stress, and that stopping smoking would deprive them of an effective stress management tool. Changes in stress levels following long-term smoking cessation are not well mapped. This longitudinal project was designed to provide more robust data on post-cessation changes in perceived stress levels by following a cohort of smokers admitted to hospital after myocardial infarction (MI) or for coronary artery bypass (CAB) surgery, as such patients typically achieve higher continuous abstinence rates than other comparable samples. Design A total of 469 smokers hospitalized after MI or CAB surgery and wanting to stop smoking were seen in the hospital and completed 1-year follow-ups. Ratings of helpfulness of smoking in managing stress at baseline, smoking status (validated by salivary cotinine concentration) and ratings of perceived stress at baseline and at 1-year follow-up were collected. Findings Of the patients, 41% (n = 194) maintained abstinence for 1 year. Future abstainers and future smokers did not differ in baseline stress levels or in their perception of coping properties of smoking. However, abstainers recorded a significantly larger decrease in perceived stress than continuing smokers, and the result held when possible confounding factors were controlled for (P < 0.001). Conclusions In highly dependent smokers who report that smoking helps them cope with stress, smoking cessation is associated with lowering of stress. Whatever immediate effects smoking may have on perceived stress, overall it may generate or aggravate negative emotional states. The results provide reassurance to smokers worried that stopping smoking may deprive them of a valuable coping resource. [source] A systematic review of interrater reliability of pressure ulcer classification systemsJOURNAL OF CLINICAL NURSING, Issue 3 2009Jan Kottner Aims., To review systematically the interrater reliability of pressure ulcer classification systems to find out which classification should be used in daily practice. Background., Pressure ulcer classification systems are important tools in research and practice. They aim at providing accurate and precise communication, documentation and treatment decisions. Pressure ulcer classifications are criticised for their low degree of interrater reliability. Design., Systematic review. Methods., The data bases MEDLINE, EMBASE, CINAHL and the World Wide Web were searched. Original research studies estimating interrater reliability of pressure ulcer classification systems were included. Study selection, data extraction and quality assessment was conducted independently by two reviewers. Results., Twenty-four out of 339 potentially relevant studies were included in the final data synthesis. Due to the heterogeneity of the studies a meaningful comparison was impossible. Conclusions., There is at present not enough evidence to recommend a specific pressure ulcer classification system for use in daily practice. Interrater reliability studies are required, in which comparable raters apply different pressure ulcer classification systems to comparable samples. Relevance to clinical practice., It is necessary to determine the interrater reliability of pressure ulcer classifications among all users in clinical practice. If interrater reliability is low the use of those systems is questionable. On the basis of this review there are no recommendations as to which system is to be given preference. [source] A survey of the mycorrhization of Southeast Asian ferns and lycophytesPLANT BIOLOGY, Issue 5 2010M. Kessler Abstract The colonisation of land by plants may not have been possible without mycorrhizae, which supply the majority of land plants with nutrients, water and other benefits. In this sense, the mycorrhization of basal groups of land plants such as ferns and lycophytes is of particular interest, yet only about 9% of fern and lycophyte species have been sampled for their mycorrhization status, and no community-level analyses exist for tropical fern communities. In the present study, we screened 170 specimens of ferns and lycophytes from Malaysia and Sulawesi (Indonesia), representing 126 species, and report the mycorrhization status for 109 species and 19 genera for the first time. Mycorrhizal colonisations were detected in 96 (56.5%) of the specimens, 85 of which corresponded to arbuscular mycorrhizae (AMF), three to dark-septate endophytes (DSE) and four to mixed colonisations (AMF + DSE). DSE colonisations were lower than in comparable samples of ferns from the Andes, suggesting a geographical or taxonomic pattern in this type of colonisation. Epiphytes had significantly lower levels of colonisation (26.1%) than terrestrial plants (70.7%), probably due to the difficulty of establishment of mycorrhizal fungi in the canopy habitat. [source] Attentional dysfunction of chronic schizophrenia: No association with long-term institutionalizationPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2002LUIGI CREMASCO MD Abstract Attentional processes play a central role in information selection, which is impaired in schizophrenic patients. In the present study, we attempted to characterize the attentional performance of chronic schizophrenics using a computerized assessment of the multiple components of attentional function. Two comparable samples, consisting, respectively, of out-patients and in-patients, were tested in order to assess the effect of chronic institutionalization. Twenty-four subjects (half in-patients and half out-patients) fulfillling DSM-IV criteria for schizophrenia were examined with a standard computerized battery for the assessment of attention, namely Testbatterie zur Aufmerksamkeitsprufung (TAP). Both groups were impaired on all measures of attentional processing (in terms of both reaction times and number of errors). There were no significant differences in attentional performance between in- and out-patients. In conclusion, the present findings confirm the presence of pervasive attentional dysfunction in chronic schizophrenia; the lack of significant differences in performance between in- and out-patients supports the hypothesis that the cognitive deficits are inherently associated with the illness and cannot be attributed to environmental/social factors. [source] | |||||||||||||