Home  About us  Contact
 

Only Small (only + small)

Distribution by Scientific Domains
Medical Sciences50%
Life Sciences20%

Terms modified by Only Small

  • only small amount
    		•
  • only small change
    		•
  • only small difference
    		•

    Selected Abstracts

    Effects of lipid extraction on stable carbon and nitrogen isotope analyses of fish tissues: potential consequences for food web studies

    ECOLOGY OF FRESHWATER FISH, Issue 3 2004
    M. A. Sotiropoulos
    Abstract,,, We examined whether solvent-based lipid extractions, commonly used for stable isotope analysis (SIA) of biota, alters ,15N or ,13C values of fish muscle tissue or whole juvenile fish. Lipid extraction from muscle tissue led to only small (<1,) isotope shifts in ,13C and ,15N values. By contrast, ecologically significant shifts (+3.4, for ,13C and +2.8, for ,15N) were observed for whole juvenile fish. Sample variance was not affected by lipid extraction. For tissue-specific SIA, two sample aliquots may be required: a lipid-extracted aliquot for stable carbon isotope analysis when differing lipid content among tissues is a concern, and a nonextracted aliquot for ,15N determination. Whole organism SIA is not recommended because of the mix of tissues having different turnover times; for very small fish, we recommend that fish be eviscerated, decapitated, and skinned to minimise differences with samples of muscle tissue. Resumen 1. Cada vez con mayor frecuencia, los ecólogos de peces utilizan análisis de isótopos estables. Por ello, se hace cada vez más importante comprender las fuentes de variación, - debido a diferencias inherentes entre muestreos biológicos o como resultado de técnicas de procesamiento de muestreo - tanto como identificar estrategias para tratar tales fuentes. Examinamos si la extracción de lípidos basada en disolventes, comúnmente utilizada en análisis de isótopos de carbono estable, altera negativamente los valores de ,15N y ,13C de tejido muscular de tres peces de tamaño pequeño y de peces juveniles completos. 2. La extracción de lípidos de músculo de pez llevó a pequeños cambios isotópicos de + +0.4 a +1.0, y de +0.3 a +0.5, para ,13C y ,15N, respectivamente. Por el contrario, la extracción de lípidos de peces juveniles completos varió marcadamente en +3.4, para ,13C y +2.8, para ,15N - ambos cambios ecológicamente importantes. La varianza de los valores de muestreos de ,13C y de ,15N tanto para tejido muscular como para los peces completos no difirieron entre los muestreos de lípidos extraídos y muestreos sin tratamiento. 3. Nuestros resultados recomiendan el análisis de isótopos estables de tejidos específicos. Cuando ello no es posible o deseable, dos alícuotas de muestreo pueden ser requeridas: una alícuota de lípidos extraídos para el análisis de isótopos de carbono estable cuando la varianza de ,13C, debida a diferencias en el contenido de lípidos de diferentes tejidos, y una alícuota de no-extracción para determinaciones de ,15N. 4. Dada la mezcla de tejidos, el análisis de isótopos de un organismo completo no es recomendable , en el caso de peces muy pequeños, recomendamos que los peces sean eviscerados, decapitados, y despellejados para minimizar las diferencias de muestreos de tejido muscular. [source]

    ,I'm the Boss': testing the feasibility of an evidence-based patient education programme using problem-based learning

    EUROPEAN DIABETES NURSING, Issue 1 2004
    K Wikblad FEND Professor in Diabetes Nursing
    Abstract Patient education programmes have shown only small to modest effects on diabetes self-care and metabolic control. Despite that, almost all diabetes teams agree that patient education is an extremely important part of the treatment of diabetes. It is, therefore, important to identify components of successful patient education as a basis for creating and testing an evidence-based education programme. In a review of controlled studies evaluating patient education such components were identified and these were then used in building up the new programme. This programme, called ,I'm the Boss', is based on the notion that the patient is an active care participant, setting his own self-care goals, and is the one responsible for his own life. The content of the programme did not, therefore, focus on diabetes as such, but on life with diabetes. Six themes were explored during six three-hour weekly sessions. The educational method used was problem-based learning. This method is founded in cognitive theory and views the learner as active in seeking knowledge and able to solve the self-care problems identified. The aim of this study was to explore the feasibility of the programme which was tested in four small groups (five to eight participants) of diabetic patients together with two facilitators. After completing the programme, the patients participated in focus group interviews to evaluate the programme. They identified both positive and negative factors. After each session the two facilitators reflected upon the group dynamics. In particular, problems with allowing patients to be the experts should be highlighted. This programme has been modified according to the evaluation and it is now being tested in a randomised, controlled, multicentre study. Copyright © 2004 FEND. [source]

    Auxiliary subunit regulation of high-voltage activated calcium channels expressed in mammalian cells

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2004
    Takahiro Yasuda
    Abstract The effects of auxiliary calcium channel subunits on the expression and functional properties of high-voltage activated (HVA) calcium channels have been studied extensively in the Xenopus oocyte expression system, but are less completely characterized in a mammalian cellular environment. Here, we provide the first systematic analysis of the effects of calcium channel , and ,2,, subunits on expression levels and biophysical properties of three different types (Cav1.2, Cav2.1 and Cav2.3) of HVA calcium channels expressed in tsA-201 cells. Our data show that Cav1.2 and Cav2.3 channels yield significant barium current in the absence of any auxiliary subunits. Although calcium channel , subunits were in principle capable of increasing whole cell conductance, this effect was dependent on the type of calcium channel ,1 subunit, and ,3 subunits altogether failed to enhance current amplitude irrespective of channel subtype. Moreover, the ,2,, subunit alone is capable of increasing current amplitude of each channel type examined, and at least for members of the Cav2 channel family, appears to act synergistically with , subunits. In general agreement with previous studies, channel activation and inactivation gating was regulated both by , and by ,2,, subunits. However, whereas pronounced regulation of inactivation characteristics was seen with the majority of the auxiliary subunits, effects on voltage dependence of activation were only small (< 5 mV). Overall, through a systematic approach, we have elucidated a previously underestimated role of the ,2,,1 subunit with regard to current enhancement and kinetics. Moreover, the effects of each auxiliary subunit on whole cell conductance and channel gating appear to be specifically tailored to subsets of calcium channel subtypes. [source]

    Factorial validity, reliability of assessments and prevalence of ADHD behavioural symptoms in day and residential treatment centres for children with behavioural problems

    INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 1 2002
    E.M. Scholte
    Abstract This study uses the attention deficit/hyperactivity disorder (ADHD) symptom ratings of professional care workers to estimate the prevalence of ADHD symptoms among children in day treatment centres (N = 162) and residential treatment centres (N = 195) in Holland. Although further research is needed, the study supports the suggestion that such ratings can add to reliable diagnostic outcomes when assessing the behavioural symptoms of ADHD in children in the centres. It is estimated that nearly a fifth of the children in such centres exhibit the symptoms of ADHD in the judgement of professional care workers. Model testing using confirmatory factor analysis favours a dimensional behavioural model that comprises all the three constitutional symptom dimensions of ADHD (inattention, hyperactivity and impulsivity) instead of the two-factor model as used in the DSM-IV (inattention and hyperactivity/impulsivity). However, the differences of fit between both models were only small and the hyperactivity and impulsivity factors were highly correlated. This suggests that, in practice, a two-factor model can also be appropriate. The issue of whether a two-factor or a three-factor model is more appropriate thus remains unsolved in this study. Copyright © 2002 Whurr Publishers Ltd. [source]

    New approaches to understanding late Quaternary climate fluctuations and refugial dynamics in Australian wet tropical rain forests

    JOURNAL OF BIOGEOGRAPHY, Issue 2 2009
    Jeremy VanDerWal
    Abstract Aim, We created spatially explicit models of palaeovegetation stability for the rain forests of the Australia Wet Tropics. We accounted for the climatic fluctuations of the late Quaternary, improving upon previous palaeovegetation modelling for the region in terms of data, approach and coverage of predictions. Location, Australian Wet Tropics. Methods, We generated climate-based distribution models for broad rain forest vegetation types using contemporary and reconstructed ,pre-clearing' vegetation data. Models were projected onto previously published palaeoclimate scenarios dating to c. 18 kyr bp. Vegetation stability was estimated as the average likelihood that a location was suitable for rain forest through all climate scenarios. Uncertainty associated with model projections onto novel environmental conditions was also tracked. Results, Upland rain forest was found to be the most stable of the wet forest vegetation types examined. We provide evidence that the lowland rain forests were largely extirpated from the region during the last glacial maximum, with only small, marginally suitable fragments persisting in two areas. Models generated using contemporary vegetation data underestimated the area of environmental space suitable for rain forest in historical time periods. Model uncertainty resulting from projection onto novel environmental conditions was low, but generally increased with the number of years before present being modelled. Main conclusions, Climate fluctuations of the late Quaternary probably resulted in dramatic change in the extent of rain forest in the region. Pockets of high-stability upland rain forest were identified, but extreme bottlenecks of area were predicted for lowland rain forest. These factors are expected to have had a dramatic impact on the historical dynamics of population connectivity and patterns of extinction and recolonization of dependent fauna. Finally, we found that models trained on contemporary vegetation data can be problematic for reconstructing vegetation patterns under novel environmental conditions. Climatic tolerances and the historical extent of vegetation may be underestimated when artificial vegetation boundaries imposed by land clearing are not taken into account. [source]

    Daily Meal Timing is Not Necessary for Resetting the Main Circadian Clock by Calorie Restriction

    JOURNAL OF NEUROENDOCRINOLOGY, Issue 2 2008
    J. Mendoza
    In rodents, entrainment and/or resetting by feeding of the central circadian clock, the suprachiasmatic nucleus (SCN), is more efficient when food cues arise from a timed calorie restriction. Because timed calorie restriction is associated with a single meal each day at the same time, its resetting properties on the SCN possibly depend on a combination of meal time-giving cues and hypocaloric conditions per se. To exclude any effect of daily meal timing in resetting by calorie restriction, the present study employed a model of ultradian feeding schedules, divided into six meals with different durations of food access (6 × 8-min versus 6 × 12-min meal schedule) every 4 h over the 24-h cycle. The effects of such an ultradian calorie restriction were evaluated on the rhythms of wheel-running activity (WRA) and body temperature (Tb) in rats. The results indicate that daily/circadian rhythms of WRA and Tb were shifted by a hypocaloric feeding distributed in six ultradian short meals (i.e. 6 × 8-min meal schedule), showing both phase advances and delays. The magnitude of phase shifts was positively correlated with body weight loss and level of day-time behavioural activity. By contrast, rats fed daily with six ultradian meals long enough (i.e. 6 × 12-min meal schedule) to prevent body weight loss, showed only small, if any, phase shifts in WRA and Tb rhythms. The results obtained reveal the potency of calorie restriction to reset the SCN clock without synchronisation to daily meal timing, highlighting functional links between metabolism, calorie restriction and the circadian timing system. [source]

    Do ,1 -adrenoceptor antagonists improve lower urinary tract symptoms by reducing bladder outlet resistance?,

    NEUROUROLOGY AND URODYNAMICS, Issue 3 2008
    Maurits M. Barendrecht
    Abstract Aims To test the hypothesis that improvements of lower urinary tract symptoms (IPSS) upon treatment with an ,-blocker are due to reduction of bladder outlet obstruction (assessed as the bladder outlet obstruction index, BOOI); relationships of either with free flow Qmax were also explored. Methods The database of a large placebo-controlled, randomized, double-blind study with the ,-blocker tamsulosin was analyzed retrospectively. Patients were stratified into lower and upper halves according to baseline IPSS, Qmax or BOOI and treatment-associated alterations thereof. In these strata differences between values for the other two parameters were analyzed, for example, improvement of IPSS and Qmax were compared in patients with below and above median improvement of BOOI. Results Patients with below and above median baseline for one parameter, for example, IPSS had rather similar values for the other two parameters, for example, Qmax and BOOI. Likewise, patients based upon baseline strata for one parameter had rather similar improvements of the other two parameters. Most importantly, patients with below and above median treatment-associated improvements of one parameter, for example, BOOI exhibited only small if any difference for alterations of the other two parameters, for example, IPPS and Qmax. Conclusions We conclude that IPSS, free flow Qmax and BOOI are only loosely related at baseline. More importantly, treatment-induced improvements of these parameters are also only loosely related. These data do question the hypothesis that ,-blockers largely improve lower urinary tract symptoms by reducing bladder outlet obstruction and suggest that they may also act independent of prostatic smooth muscle tone. Neurourol. Urodynam. 27:226,230, 2008. © 2007 Wiley-Liss, Inc. [source]

    Effects of fertilization on understorey vegetation in a Norwegian Pinus sylvestris forest

    APPLIED VEGETATION SCIENCE, Issue 2 2002
    Astrid Skrindo
    Abstract. Boreal coniferous forests have been impacted by long distance airborne pollutant deposition for most of the 20th century. Changes in forest understorey vegetation attributable to N-deposition have been observed in southern Sweden, but not so far in southern Norway. We recorded the quantity of all species of vascular plants, bryophytes and lichens in 144 plots in a fertilization experiment in a 35-yr old Pinus sylvestris forest in Aust Agder County, southernNorway initiated 6 yr before our study. Each plot represented a combination of three levels of nitrogen, two levels of magnesium and two levels of phosphorus addition. Effects of fertilization on species quantity were tested by Kruskal-Wallis one-way analysis by ranks. For vascular plants, only small and hardly significant differences were found between treatments and control. Significant negative effects of N-fertilization were found on both mosses and lichens. To some extent, these effects could be attributed to direct effects of application of the fertilizer, but were more likely to be due to a negative feedback response to the faster growth of pine trees in fertilized stands, reducing throughfall precipitation and increasing litter fall. Significant differences between Mg- and P-fertilized sites and respective controls were found for too few species to be likely to represent an overall trend. [source]

    A NEW DESIGN APPROACH TO DELAY-DEPENDENT ROBUST H, CONTROL FOR UNCERTAIN TIME-DELAY SYSTEMS

    ASIAN JOURNAL OF CONTROL, Issue 4 2004
    Ning-Jun Su
    ABSTRACT A new design approach to delay-dependent robust stabilization and robust H, control for a class of uncertain time-delay systems is provided in this paper. The sufficient conditions for delay-dependent robust stabilization and robust H, control are derived based on a new state transformation and given in terms of linear matrix inequalities (LMI). Numerical examples are presented to show that the proposed results can be less conservative and can be used to deal with not only small but also large delay systems. [source]

    USE OF COMMUNITY HEALTH NEEDS ASSESSMENT FOR REGIONAL PLANNING IN COUNTRY SOUTH AUSTRALIA

    AUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 1 2001
    Jeff Fuller
    ABSTRACT: This study examined the impact of community health needs assessments used in country South Australian health service planning between 1995 and 1999. Data were collected from regional health planning officers during a Search Conference and a series of Delphi rounds. The needs assessments were found to vary from regionally to locally driven approaches. Locally driven approaches ensured local involvement but the process was slower and required more effort from the planner. It was also felt that locally driven approaches could exacerbate tension between a community's imperatives and the regional focus of regional decision-makers. In the overall regional budgets, the reallocation of health service funds according to the needs assessment findings was only small because of difficulties in refocusing from traditional clinical services in the short term. In contrast, the impact on health service thinking about population health issues was thought to have been more significant, for example, in the development of regional women's health plans. The use of community health needs assessments was useful, but for greater impact these should not now be so ,broad-brushed', but be more focused on feasible changes that health services could support. Other priority-setting techniques, such as marginal analysis, should also be used to determine where maximum health gains can be obtained. [source]