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Reliable Predictor (reliable + predictor)
Selected AbstractsVariability of dry sediment bulk density between and within retention ponds and its impact on the calculation of sediment yieldsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2001Gert Verstraeten Abstract Monitoring sediment yields from catchments is important for assessing overall denudation rates and the impact of environmental change. One of the methods used to assess sediment yield is by quantifying sedimentation rates in reservoirs, lakes or small ponds. Before reliable sediment yield values (t ha,1 a,1) can be computed from such sedimentation records, the measured sediment volumes need to be converted to sediment masses using representative values of the dry sediment bulk density. In textbooks, simple relations predicting dry sediment bulk density from sediment texture, time since deposition and hydrologic condition are presented. In this study, 13 small flood retention ponds in central Belgium were sampled to reveal the variability in dry sediment bulk density and to test the commonly used relations to predict dry sediment bulk density. Dry sediment bulk density varies not only between the selected ponds (0·78,1·35 t,m,3) but also within individual ponds (coefficient of variation at 95 per cent ranges from 7 to 80 per cent). The observed variability can be attributed primarily to the hydrologic condition of the retention pond and, also, to sediment texture. The existing relations are not a reliable predictor for the observed dry bulk densities, because they are primarily based on sediment texture. Thus, when using volumetric sedimentation data from small ponds with varying hydrologic condition to predict sediment yield, existing relations predicting dry sediment bulk density cannot be applied. Instead, frequent and dense sampling of sediments is necessary to calculate a representative value of the dry sediment bulk density. Copyright © 2001 John Wiley & Sons, Ltd. [source] Horn size predicts physical performance in the beetle Euoniticellus intermedius (Coleoptera: Scarabaeidae)FUNCTIONAL ECOLOGY, Issue 4 2005S. P. LAILVAUX Summary 1In many animals, the size of secondary sexual ornaments is known to be related to the probability of victory in fights between males, and hence to fighting ability. However, few studies have attempted to link fighting ability to any physical performance measures. 2Here we show that horn size in the dung beetle Euoniticellus intermedius accurately predicts two types of whole-organism performance, independent of body size, that are likely to play an important role in male contests: the force required to pull a beetle out of a tunnel, and the distance the beetle was able to run before exhaustion (maximum exertion). 3Body length is also a statistically significant predictor of pulling force, but not of exertion, suggesting that horn size is a more reliable predictor of performance than body size alone, a result that is consistent with a previous finding that horn size becomes more important in determining victory in male,male contests as body size increases. 4This study is the first to establish direct links between whole-organism performance abilities, male armaments and fighting ability in the same species. Our findings suggest that physiological performance capacities are important factors underlying the evolution of signal expression in E. intermedius, and should be considered in future studies of the evolution of animal signalling. [source] Reassessing the impact of North Atlantic Oscillation on the sub-Saharan vegetation productivityGLOBAL CHANGE BIOLOGY, Issue 4 2003GUILING WANG Abstract The Northern Atlantic Oscillation (NAO) has been shown to have a significant impact on the terrestrial ecosystem in the Sahelian region of Africa during the 1980s, and it has been strongly suggested that NAO may be a reliable predictor for the response of the Sahelian ecosystem to global climate variability. Using data from an extended period, we provide a reassessment for the impact of NAO on the Sahelian climate and ecosystem, and show that there is no consistent relationship between NAO and the ecosystem over Sahel. Statistical analysis on the NAO, vegetation, and precipitation data indicates that NAO influences the Sahelian vegetation productivity exclusively through its impact on precipitation. However, the relationship between the NAO index and Sahelian precipitation varies substantially with time. The correlation coefficient fluctuates between positive and negative values, and does not pass the 5% significance test during most of the twentieth century. The NAO system, although documented to govern the ecosystem dynamics over many other regions, does not have a consistent impact on the ecosystem over the Sahel. Therefore, the NAO index cannot produce a useful prediction on the ecosystem variability and changes in this region. This study provides an example that correlations based on short climate and ecological records (less than 20 years in this case) can be spurious and potentially misleading. [source] Surgical treatment of migraine headaches.HEADACHE, Issue 3 2003B Guyuron Plast Reconstr Surg. 2002 Jun;109(7):2183-2189 This prospective study was conducted to investigate the role of removal of corrugator supercilii muscles, transection of the zygomaticotemporal branch of the trigeminal nerve, and temple soft-tissue repositioning in the treatment of migraine headaches. Using the criteria set forth by the International Headache Society, the research team's neurologist evaluated patients with moderate to severe migraine headaches, to confirm the diagnosis. Subsequently, the patients completed a comprehensive migraine headaches questionnaire and the team's plastic surgeon injected 25 units of botulinum toxin type A (Botox) into each corrugator supercilii muscle. The patients were asked to maintain an accurate diary of their migraine headaches and to complete a monthly questionnaire documenting pertinent information related to their headaches. Patients in whom the injection of Botox resulted in complete elimination of the migraine headaches then underwent resection of the corrugator supercilii muscles. Those who experienced only significant improvement underwent transection of the zygomaticotemporal branch of the trigeminal nerve with repositioning of the temple soft tissues, in addition to removal of the corrugator supercilii muscles. Once again, patients kept a detailed postoperative record of their headaches. Of the 29 patients included in the study, 24 were women and five were men, with an average age of 44.9 years (range, 24 to 63 years). Twenty-four of 29 patients (82.8 percent, p < 0.001) reported a positive response to the injection of Botox, 16 (55.2 percent, p < 0.001) observed complete elimination, eight (27.6 percent, p < 0.04) experienced significant improvement (at least 50 percent reduction in intensity or severity), and five (17.2 percent, not significant) did not notice a change in their migraine headaches. Twenty-two of the 24 patients who had a favorable response to the injection of Botox underwent surgery, and 21 (95.5 percent, p < 0.001) observed a postoperative improvement. Ten patients (45.5 percent, p < 0.01) reported elimination of migraine headaches and 11 patients (50.0 percent, p < 0.004) noted a considerable improvement. For the entire surgical group, the average intensity of the migraine headaches reduced from 8.9 to 4.1 on an analogue scale of 1 to 10, and the frequency of migraine headaches changed from an average of 5.2 per month to an average of 0.8 per month. For the group who only experienced an improvement, the intensity fell from 9.0 to 7.5 and the frequency was reduced from 5.6 to 1.0 per month. Only one patient (4.5 percent, not significant) did not notice any change. The follow-up ranged from 222 to 494 days, the average being 347 days. In conclusion, this study confirms the value of surgical treatment of migraine headaches, inasmuch as 21 of 22 patients benefited significantly from the surgery. It is also evident that injection of Botox is an extremely reliable predictor of surgical outcome. Comment: Many small placebo-controlled studies and much anecdotal literature suggests that botulinum toxin may be effective in prevention of migraine, perhaps to the same extent as conventional prophylactic treatment. Larger, randomized clinical trials are underway to resolve this issue. In the meantime, those who believe in the effectiveness of botulinum toxin prophylaxis argue about how it works, that is whether its antinociceptive properties are due to peripheral effects, central or presynaptic effects, or both. Dr. Guyuron's group favors the idea that botulinum toxin interrupts a reflex arc between the central nervous system (CNS) and peripheral musculature, and that after establishing efficacy by low dose botulinum injection in the corrugator supercilii muscles, surgical resection of these muscles results in prolonged and effective prophylaxis. The idea is radical but intriguing and should not be dismissed out of hand. However, a trial is necessary in which both the botulinum toxin injections are blinded with vehicle, and the study of the surgery involves a sham surgery control group with extended long-term follow-up, before these forms of prophylaxis can be recommended to patients. SJT [source] Depression status as a reliable predictor of functional decline among Japanese community-dwelling older adults: a 12-year population-based prospective cohort studyINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 11 2009Hajime Iwasa Abstract Objective This study aimed to examine a longitudinal relationship between depression status and functional decline among Japanese community-dwelling older adults, using a 12-year population-based, prospective cohort study design. Method A total of 710 men and women, aged 65 years and over, participated in the study. Katz's Index and the Tokyo Metropolitan Institute of Gerontology Index of Competence were used to measure the functional capacities of basic activities of daily living (BADL) and higher-level competence, respectively. For the purpose of analysis, a decline in each subscale of functional capacity during the follow-up period were used as outcome variables; depression status assessed by the Japanese version of the 30-item Geriatric Depression Scale (GDS), with a cut-off of 11, was used as an independent variable; and age, gender, education level, history of chronic disease, hospitalization, smoking, physical activity, living alone, hearing problems, physical pain, dietary habits, and usual walking speed at baseline were used as covariates. Results Use of the multivariate Cox proportional hazards model adjusted for potential confounders showed that depression status was significantly and independently associated with BADL decline (risk ratio (RR),=,1.46, 95% confidence interval (CI): 1.13,1.89) and with higher-level competence decline (RR,=,1.56, 95% CI: 1.18,2.04). Conclusion Our study found an independent relationship between depression status and longitudinal change in functional capacity among community-dwelling older individuals, suggesting that depression status is a reliable predictor of functional decline (both of BADL decline and higher-level competence decline) in older adults. Copyright © 2009 John Wiley & Sons, Ltd. [source] Should dynamic parameters for prediction of fluid responsiveness be indexed to the tidal volume?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010S. T. VISTISEN Background: The respiratory variation in the pre-ejection period (,PEP) has been used to predict fluid responsiveness in mechanically ventilated patients. Recently, we modified this parameter (PEPV) and showed that it was a reliable predictor for post-cardiac surgery, mainly paced, patients when moderately low tidal volumes were used. One of the modifications involved tidal volume indexation, which had not been proposed before for dynamic parameters. The aim of the present animal study was to investigate whether indexation to tidal volume should be part of a new definition of dynamic parameters such as the case for our newly proposed PEPV. Methods: Eight prone, anesthetized piglets (23,27 kg) were subjected to a sequence of 25% hypovolemia, normovolemia, and 25% and 50% hypervolemia. At each volemic level, tidal volumes were varied in three steps: 6, 9, and 12 ml/kg. PEP variations (ms) and pulse-pressure variation (PPV) were measured during the three tidal volume steps at each volemic level. Results: PEP variations increased significantly with increasing tidal volume at all volemic levels but 50% hypervolemia and were proportionally related to the tidal volume at normovolemia. PPV increased significantly with increasing tidal volume at all volemic levels and was roughly proportional to the tidal volume at all volemic levels but hypovolemia. Conclusion: Our study indicates that dynamic parameters are improved by indexing to tidal volume. [source] Automated pre-ejection period variation predicts fluid responsiveness in low tidal volume ventilated pigsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010S. T. VISTISEN Introduction: The respiratory variation in the pre-ejection period (,PEP) has been used to predict fluid responsiveness in mechanically ventilated patients. Recently, we automated this parameter and indexed it to tidal volume (PEPV) and showed that it was a reliable predictor for post-cardiac surgery, mainly paced, patients ventilated with low tidal volumes. The aims of the present animal study were to investigate PEPV's ability to predict fluid responsiveness under different fluid loading conditions and natural heart rates during low tidal volume ventilation (6 ml/kg) and to compare the performance of PEPV with other markers of fluid responsiveness. Methods: Eight prone, anesthetized piglets (23,27 kg) ventilated with tidal volumes of 6 ml/kg were subjected to a sequence of 25% hypovolemia, normovolemia, and 25% and 50% hypervolemia. PEPV, ,PEP, pulse pressure variation (PPV), central venous pressure (CVP), and pulmonary artery occlusion pressure (PAOP) were measured before each volume expansion. Results: Sensitivity was 89% and specificity was 93% for PEPV, 78% and 93% for ,PEP, 89% and 100% for PPV, 78% and 93% for CVP, and 89% and 87% for PAOP. Conclusion: PEPV predicts fluid responsiveness in low tidal volume ventilated piglets. [source] An experimental test of the link between foraging, habitat selection and thermoregulation in black rat snakes Elaphe obsoleta obsoletaJOURNAL OF ANIMAL ECOLOGY, Issue 6 2001Gabriel Blouin-Demers Summary 1Most physiological processes are temperature-dependent. Thus, for ectotherms, behavioural control of body temperatures directly affects their physiology. Ectotherms thermoregulate by adjusting habitat use and therefore thermoregulation is probably the single most important proximate factor influencing habitat use of terrestrial reptiles, at least in temperate climates. 2Snakes have been shown to raise their body temperature following feeding in a laboratory thermal gradient, presumably to enhance digestion. This experiment was exported to the field to explore the link between feeding, habitat selection and thermoregulation in free-ranging snakes. 3Experimental feeding was conducted in the laboratory and in the field on black rat snakes (Elaphe obsoleta obsoleta) that had temperature-sensitive radio-transmitters surgically implanted. 4Snakes had higher mean body temperatures following feeding than prior to feeding in a laboratory thermal gradient. 5Some, but not all evidence, indicated that black rat snakes increased their mean body temperature following feeding in the field. Indices of thermoregulation indicated that the snakes thermoregulated more carefully and more effectively after they had eaten. 6Forest edges provided the best opportunities for thermoregulation in the study area. Black rat snakes were less likely to move following feeding when fed in edges than when fed in the forest and were more likely to be found in edges following feeding, whether they had been fed in the forest or in an edge. 7Results of this study and one previous study suggest that thermoregulatory behaviour of snakes following feeding in the laboratory is a reliable predictor of their behaviour in the field. A review of 13 studies of the thermoregulatory behaviour of snakes following feeding in the laboratory revealed that not all species behave similarly. However, the quality and number of studies currently available is not adequate for testing hypotheses about which species should change thermoregulatory behaviour in response to eating and which should not. [source] Honest olfactory ornamentation in a female-dominant primateJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 7 2010M. BOULET Abstract Sexual selection theory predicts that potential mates or competitors signal their quality to conspecifics. Whereas evidence of honest visual or vocal signals in males abounds, evidence of honest signalling via scent or by females is scarce. We previously showed that scent marks in male lemurs seasonally encode information about individual heterozygosity , a reliable predictor of immunocompetence and survivorship. As female lemurs dominate males, compete over resources, and produce sexually differentiated scent marks that likely evolved via direct selection, here we tested whether females also advertise genetic quality via olfactory cues. During the breeding season specifically, individual heterozygosity correlated negatively with the diversity of fatty acids (FAs) expressed in labial secretions and positively with the diversity of heavy FA esters. As odour,gene relationships predictive of health and survivorship emerged during a period critical to mate choice and female competition, we posit that genital scent marks function as honest olfactory ornaments in females. [source] Attraction of ambrosia and bark beetles to coast live oaks infected by Phytophthora ramorumAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2008Brice A. McPherson Abstract 1,Sudden oak death is caused by the apparently introduced oomycete, Phytophthora ramorum. We investigated the role of bark and ambrosia beetles in disease progression in coast live oaks Quercus agrifolia. 2,In two Marin County, California sites, 80 trees were inoculated in July 2002 with P. ramorum and 40 were wounded without inoculation. Half of the trees in each group were sprayed with the insecticide permethrin [cyclopropanecarboxylic acid, 3-(2,2-dichloroethenyl)-2,2-dimethyl-(3-phenoxyphenyl) methyl ester] to prevent ambrosia and bark beetle attacks, and then were sprayed twice per year thereafter. After each treatment, sticky traps were placed on only the permethrin-treated trees. Beetles were collected periodically in 2003. 3,Inoculated trees accounted for 95% of all beetles trapped. The ambrosia beetles Monarthrum scutellare and Xyleborinus saxeseni and the western oak bark beetle Pseudopityophthorus pubipennis were the most abundant of the seven species trapped. 4,Permethrin treatment delayed initiation of beetle attacks and significantly reduced the mean number of attacks per tree. Beetles did not attack any wounded or noncankered inoculated trees. 5,Trees with larger cankers trapped more beetles early in the disease. Once permethrin lost effectiveness, the number of beetle entrance tunnels was a more reliable predictor of subsequent trap catch than was canker size. 6,Beetles were initially attracted to P. ramorum cankers in response to kairomones generated in the host-pathogen interaction. After beetles attacked the permethrin-treated trees, aggregation pheromones most probably were the principal factor in beetle colonization behaviour. [source] Measurement of serum hyaluronic acid in patients with chronic hepatitis C and its relationship to liver histologyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2000John G McHutchison Abstract Background and Aims: Chronic hepatitis C is a slowly progressing inflammatory disease of the liver that can lead to cirrhosis and its complications. Assessment of liver damage in hepatitis C has been primarily via histological evaluation. Liver biopsy, while useful in determining the extent of liver damage, has associated costs and places patients at a small but finite risk of bleeding. Studies in small patient populations have identified serum markers shown to correlate with liver histology, including pro-collogen III peptide and hyaluronic acid (HA). To determine whether serum HA was a reliable predictor of cirrhosis and fibrosis, we examined serum HA concentrations from 486 chronic Hepatitis C virus (HCV) patients. Methods and Results: Patients were anti-HCV and HCV RNA positive, with elevated alanine aminotransferase values and underwent a liver biopsy. Sera were obtained at the baseline for HA using radioimmunoassay methodology. Patients with cirrhosis had significantly higher serum HA concentrations compared with non-cirrhotic patients (382 ± 31 vs 110 ± 9 ,g/L respectively, P < 0.001). Patients with fibrosis had significantly higher mean serum HA concentrations (179 ± 11 ,g/L) compared with patients without fibrosis (62 ± 20 ,g/L; P < 0.001). The correlation between HA concentration and the components of the Knodell histological activity index score revealed no strong associations with the exception of fibrosis, which showed moderate correlation (R = 0.5421, P < 0.001). The clinical value of HA measurement appears to be its ability to exclude cirrhosis. A HA value of < 60 ,g/L excluded the presence of cirrhosis or significant fibrosis with a predictive value of 99 and 93%, respectively. Conclusions: Serum HA measurement may be clinically useful to non-invasively assess the degree of fibrosis and cirrhosis. Further prospective studies are warranted to determine the clinical utility of HA as a non-invasive marker of liver fibrosis. [source] Emotional intelligence: a vital prerequisite for recruitment in nursingJOURNAL OF NURSING MANAGEMENT, Issue 6 2001C. Cadman MED This paper explores Goleman's (1996) concept of ,emotional intelligence' in relation to recruitment to preregistration nurse education programmes. Current studies consistently demonstrate that emotional intelligence is the common factor which marks out individuals as leaders, innovators and effective managers. The role of the qualified nurse is evolving continually and ,portable' skills are the key qualities demanded by a health care system under pressure to compete. These include the ability to work effectively in teams, the ability to recognize and respond appropriately to one's own and others' feelings and the ability to motivate oneself and others. They are collectively termed ,emotional intelligence'. We believe we need selection processes that will determine levels of emotional intelligence in prospective candidates, as they could be a reliable predictor of success in both clinical nursing practice and academic study. Research indicates that emotional intelligence cannot be developed quickly enough through interpersonal skills training and therefore it is essential that nurse educators create assessment strategies that will identify emotional intelligence at recruitment. [source] Sentinel lymph node as a new marker for therapeutic planning in breast cancer patientsJOURNAL OF SURGICAL ONCOLOGY, Issue 3 2004Marco Gipponi MD Abstract Background and Objectives Literature review suggests that the sentinel lymph node (sN) represents a reliable predictor of axillary lymph node status in breast cancer patients; however, some important issues, such as the optimisation of the technique for the intraoperative identification of the sN, the role of intraoperative frozen section examination of the sN, and the clinical implications of sN metastasis as regards the surgical management of the axilla, still require further confirmation. The authors aimed (1) to assess the feasibility of sN identification with a combined approach (vital blue dye lymphatic mapping and radioguided surgery, RGS) and the specific contribution of either techniques to the detection of the sN, (2) to determine the accuracy and usefulness of intraoperative frozen section examination of the sN in order to perform a one-stage surgical procedure, and (3) to define how the sN might modulate the therapeutic planning in different stages of disease. Materials and Methods From October 1997 to June 2001, 334 patients with early-stage (T1,2 N0 M0) invasive mammary carcinoma underwent sN biopsy; the average age of patients was 61.5 years (range, 39,75 years). In a subset of 153 patients, both vital blue dye (Patent Blue-V) lymphatic mapping and RGS were used to identify the sN, and the relative contribution of each of the two techniques was assessed. Results In the whole group, the sN was identified in 326 of 334 patients (97.6%), and 105 of 326 patients (37.3%) had positive axillary lymph nodes (pN+). In 9 of 105 pN+ patients, the definitive histologic examination of the sN did not show metastases but these were detected in non-sN, thus giving an 8.6% false-negative rate, a negative predictive value of 94.5% (156/165), and an accuracy of 96.5% (252/261). As regards the specific contribution of the two different techniques used in the identification of the sN, the detection rate was 73.8% (113/153) with Patent Blue-V alone, 94.1% (144/153) with RGS alone, and 98.7% (151/153) with Patent Blue-V combined with RGS (P,<,0.001). Noteworthy, whenever the sN was identified, the prediction of axillary lymph node status was remarkably similar (93,95% sensitivity; 100% specificity; 95,97% negative predictive value, and 97,98% accuracy) whichever of the three procedures was adopted (Patent Blue-V alone, RGS alone, or combined Patent Blue-V and RGS). Intraoperative frozen section examination was performed in 261 patients, who had at least one sN identified, out of 267 patients who underwent complete axillary dissection; 170 patients had histologically negative sN (i.o. sN,) and 91 patients histologically positive sN (i.o. sN+). All 91 i.o. sN+ were confirmed by definitive histology, whereas in 14 of 170 i.o. sN, patients (8.2%) metastases were detected at definitive histology. As regards the correlation between the size of sN metastasis, the primary tumour size, and the status of non-sN in the axilla, micrometastases were detected at final histology in 23 patients and macrometastases in 82 patients. When only micrometastases were detected, the sN was the exclusive site of nodal metastasis in 20 of 23 patients (86.9%) while in 3 patients with tumour size larger than 10 mm micrometastases were detected also in non-sN. Macrometastases were never detected in pT1a breast cancer patients; the sN was the exclusive site of these metastases in 30 patients (36.6%), while in 52 patients (63.4%) there were metastases both in sN and non-sN. Conclusions Sentinel lymphadenectomy can better be accomplished when both procedures (lymphatic mapping with vital blue dye and RGS) are used, because of the significantly higher sN detection rate, although the prediction of axillary lymph node status remains remarkably similar whichever method is used. The intraoperative frozen section examination proved to be rather accurate in predicting the actual pathologic status of the sN, with a negative predictive value of 91.8%; in 35% of patients it allowed sN biopsy and axillary dissection to be performed in a one-stage surgical procedure. Finally, specific clinical and histopathologic features of the primary tumour and sN might be used to tailor the loco-regional and systemic treatment in different clinical settings, such as in ductal carcinoma in-situ (DCIS), early-stage invasive breast cancer, and patients with large breast cancer undergoing neo-adjuvant CT for breast-saving surgery as well as elderly patients with operable breast cancer. J. Surg. Oncol. 2004;85:102,111. © 2004 Wiley-Liss, Inc. [source] Host serological response to Helicobacter pylori after successful eradication: long-term follow-up in patients with cured and persistent infectionALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 2006J. TANAKA Summary Aim To systematically determine the usefulness of Helicobacter pylori IgG antibody titer decline as a predictor of treatment success after H. pylori eradication in large patient samples. Patients and Methods Serum samples from 258 H. pylori positive patients (52.8 yrs, 65% males) were retrospectively collected from five medical centers, and H. pylori titers were quantitatively determined by ELISA. Serial serum samples were collected at baseline and for up to 4.9 years after treatment. 169 patients underwent successful eradication while 89 remained infected. The median total observation period was 635 days (range, 51 to 1,800 days). Chronological changes in H. pylori titers were analyzed and compared between cured and infection persistent subjects. Results The proportion of infection persistent patients who developed negative H. pylori IgG antibody titers was below 5%. A receiver operating characteristic (ROC) curve for the confirmation of successful eradication according to the percent decline over baseline at each time-point showed that a 60% decline at 1 year or more after eradication treatment strongly correlated with successful eradication (sensitivity = 90% and specificity = 87%). Conclusion A 60% decline in H. pylori IgG titers (HEL-p kit) from baseline to one year or greater is a reliable predictor of successful H. pylori eradication. [source] Postprandial oesophageal integrated acidity is a reliable predictor of gastro-oesophageal reflux diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 12 2005G. L. Shih Summary Background :,Measurement of oesophageal acid exposure parameters postprandially has been shown to distinguish gastro-oesophageal reflux disease patients from normal individuals. Aims :,To calculate the accuracy of postprandial oesophageal integrated acidity in diagnosing gastro-oesophageal reflux disease. Methods :,Ambulatory 24-h pH studies of 626 patients were analysed retrospectively. Gastro-oesophageal reflux disease, defined as pH < 4 for >4.2% of time, was identified in 305 subjects. Postprandial oesophageal integrated acidity was measured for 2 and 3 h after the largest meal peak as determined from gastric pH. Postprandial symptom-associated probability was calculated. Results :,Gastro-oesophageal reflux disease subjects had a greater postprandial oesophageal integrated acidity than non-gastro-oesophageal reflux disease subjects [median (IQR): 0.57 (0.08,2.66) vs. 0.03 (0.01,0.15) mmol*h/L]. Median postprandial oesophageal integrated acidity did not differ with gender or age in gastro-oesophageal reflux disease and non-gastro-oesophageal reflux disease subjects (P > 0.05 for all). A 3-h postprandial oesophageal integrated acidity value of 0.121 mmol*h/L had a 71.1% sensitivity and 71.7% specificity in diagnosing gastro-oesophageal reflux disease. Gastro-oesophageal reflux disease subjects with symptoms had a higher postprandial oesophageal integrated acidity than those without (P = 0.043), whereas non-gastro-oesophageal reflux disease subjects with and without symptoms did not differ (P = 0.74). The correlation between symptom-associated probability and postprandial oesophageal integrated acidity was poor (gastro-oesophageal reflux disease: r = 0.15; non-gastro-oesophageal reflux disease: r = 0.25). Conclusion :,Postprandial oesophageal integrated acidity provides a robust estimation of oesophageal acid exposure and may predict symptoms in gastro-oesophageal reflux disease patients. [source] Qualitative aspects of sperm stock in males and females from Eupelmus orientalis and Dinarmus basalis (Hymenoptera: Chalcidoidea) as revealed by dual fluorescencePHYSIOLOGICAL ENTOMOLOGY, Issue 2 2002David Damiens Abstract The quality of a sperm population can be characterized physiologically and its fecundity predicted by its viable : non-viable sperm ratio. To improve the knowledge of reproductive strategies in two ectoparasitoid hymenopteran species, Eupelmus orientalis Crawford (Hymenoptera: Eupelmidae) and Dinarmus basalis Rondani (Hymenoptera: Pteromalidae), the assessment of sperm viability using the dual fluorescence staining procedure SYBR-14 : propidium iodide was developed. The aim of the study was to provide a comparative test in vitro applicable to both sexes to study the evolution of sperm quality at various stages of the reproductive processes. The reliability of propidium iodide to detect non-viable sperm (stained in red) was confirmed in both species on the basis of two stress tests (ethanol and Triton X-100) but our study also revealed that propidium iodide concentrations must be adequately adjusted for each single species. This experiment also demonstrated the physiological heterogeneity of sperm populations in E. orientalis and D. basalis males and females. In both species, 40% of the sperm in the seminal vesicles was found to be non-viable. By contrast with E. orientalis, the populations of non-viable sperm estimated from the seminal vesicles of D. basalis were found to be strongly different from those observed in the spermatheca. From the present results, the population of viable sperm detected in the spermatheca of females from both species proved a reliable predictor of fertilization achieved in ovipositing females. [source] Plant foods consumed by Pan: Exploring the variation of nutritional ecology across AfricaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2010Gottfried Hohmann Abstract It has been shown that differences in resource density and nutrient supply affect variation in ranging patterns, habitat use, and sociality. Among nonhuman primates, chimpanzees (Pan troglodytes) and bonobos (P. paniscus) have often been used as models for the link between social system and habitat ecology. Field reports suggest that resource density is higher in habitats occupied by bonobos (compared to chimpanzee habitats), and in the West (compared to the East) of the range of chimpanzees. In this study we compared diet quality at the level of species and populations using information from nutritional analyses of fruit and leaves consumed by chimpanzees (three) and bonobos (one population). Quality of plant foods was assessed on the basis of a) the concentration of macronutrients, fiber, and anti-feedants, and b) associations of different nutrient components. Overall plant samples collected at each site differed in terms of macronutrient content. However, nutritious quality and gross energy content of food samples were similar suggesting that dietary quality reflects selectivity rather than habitat ecology. The quality of plant foods consumed by bonobos was within the range of chimpanzees and the quality of plant foods consumed by western chimpanzees was not higher than that of eastern chimpanzees. While the results showed significant variation across forests inhabited by Pan, they did not match with geographical patterns between and within Pan species as proposed in previous studies. This suggests that the nutritional quality of the habitat is not always a reliable predictor of the quality of the diet. Am J Phys Anthropol 2010. © 2009 Wiley-Liss, Inc. [source] New Method for Predicting the Lumbar Lordosis Angle in Skeletal MaterialTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2007Ella Been Abstract Reconstructing the lordotic curvature of the lumbar spine in humans is essential for understanding their posture and locomotion. To date there is still no reliable method for predicting the lordotic curvature of disarticulated spines (in the absence of intervertebral disks). This article examines two possible methods for predicting the lordotic curvature of the lumbar spine. The first,the traditional method,is based on the degree of wedging of the vertebral bodies, and the second,the suggested new method,is based on a lateral view of the orientation of the inferior articular processes. We propose a linear regression model for predicting the lordotic curvature of the lumbar spine (lordosis angle) in disarticulated human spines. This model, derived directly from our new method, is a more reliable predictor of the lumbar lordosis angle in disarticulated spines. Anat Rec, 2007. © 2007 Wiley-Liss, Inc. [source] Serum intact parathyroid hormone as a predictor of hypocalcaemia after total thyroidectomyANZ JOURNAL OF SURGERY, Issue 11 2005Patsy S. H. Soon Background: Hypocalcaemia from hypoparathyroidism is a complication of total thyroidectomy. The aim of the present study was to determine whether an early postoperative level of serum parathyroid hormone (PTH) after total thyroidectomy predicts the development of significant hypocalcaemia and the need for treatment. Methods: Patients undergoing total thyroidectomy had their serum level of intact PTH checked 1 h after removal of the thyroid gland. Serum calcium level was checked on the following morning. Oral calcium and/or calcitriol was commenced if the patient developed hypocalcaemic symptoms, or if the corrected serum calcium level was <2.0 mmol/L. Results: Seventy-nine patients were included in the present study. Thirteen patients had symptoms of hypocalcaemia on postoperative days 1 or 2 and 66 patients remained asymptomatic. The postoperative intact PTH, day 1 calcium and day 2 calcium was 0.32 ± 0.60 pmol/L, 2.01 ± 0.11 mmol/L, and 2.02 ± 0.16 mmol/L, respectively, for the symptomatic group and 1.98 ± 1.25, 2.21 ± 0.13, and 2.19 ± 0.14, respectively, for the asymptomatic group. Calcium support was given to 25 patients, of whom 14 also required calcitriol. Conclusion: Serum PTH 1-h after total thyroidectomy is a reliable predictor of hypocalcaemia and can allow safe early discharge of patients from hospital. [source] Correlation of intravesical prostatic protrusion with bladder outlet obstructionBJU INTERNATIONAL, Issue 4 2003S.J. Chia OBJECTIVES To determine the effect of intravesical protrusion of the prostate (IPP, graded I to III) on lower urinary tract function, by correlating it with the results of a pressure-flow study. PATIENTS AND METHODS In a prospective study men (aged> 50 years) with lower urinary tract symptoms were initially evaluated as recommended by the International Consultation on Benign Prostatic Hyperplasia, together with the IPP and prostate volume, as measured by transabdominal ultrasonography. These variables were then correlated with the results from a pressure-flow study. RESULTS The IPP was a statistically significant predictor (P < 0.001) of bladder outlet obstruction (BOO) compared with other variables in the initial evaluation. In all, 125 patients had significant BOO, defined as a BOO index of> 40. Of these men, 94 had grade III and 30 had grade I,II IPP. Seventy-five patients had a BOO index of < 40; 69 had grade I,II and six grade III IPP. In patients with BOO confirmed on the pressure-flow study, grade III IPP was associated with a higher BOO index than was grade I,II (P < 0.001). CONCLUSION The IPP assessed by transabdominal ultrasonography is a better and more reliable predictor of BOO than the other variables assessed. [source] Effect of high-dose intravenous immunoglobulin in delayed pressure urticariaBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2003G. Dawn Summary Background Delayed pressure urticaria (DPU) is difficult to treat. High-dose intravenous immunoglobulin (IVIG) has been found to be effective in treating patients with autoimmune chronic urticaria. Objectives To report the effect of IVIG on eight patients with severe unremitting DPU. Methods IVIG was administered at a dose of 2 g kg,1 over 2,3 days on an in-patient basis. The response to treatment was assessed subjectively and recorded as remission, improved or unchanged. An autologous serum skin test (ASST) was performed in seven patients. Results Three of eight patients achieved remission; two after one infusion and one after three infusions. Two patients improved. Three patients remained unchanged; of these, two declined further treatment after two infusions, and one failed to improve after six infusions at monthly intervals. Four of seven patients had positive ASST; three responded to IVIG. Two developed delayed positive ASST; both responded to IVIG. Of three patients with negative ASST, two responded. Conclusions IVIG induced remission or improved symptoms in five of eight patients with DPU with severe unremitting disease who had failed to respond to other therapies or were controlled only with systemic corticosteroids. Those who responded did so with three or fewer infusions. ASST is not a reliable predictor of response to IVIG. [source] The interactive effects of personal traits and guided practices on preservice teachers' changes in personal teaching efficacyBRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 4 2006Yu-Chu Yeh Personal teaching efficacy is associated with a teacher's effectiveness in the classroom. To enhance this efficacy in a computer-simulated training program, both personal traits and guided practices need to be considered concurrently. In this study, it was hypothesised that the interactive effects from the coupling of personal traits with guided practices would be a reliable predictor of the degree of improvement in personal teaching efficacy during computer-simulated training. One hundred and seventy-eight preservice teachers completed an interactive teaching experience via the Computer Simulation for Teaching General Critical-thinking Skills in which guided practices were integrated via specially designed teaching sequences and loops. The findings suggest that intrapersonal intelligence, critical-thinking dispositions and a judicial thinking style are related to self-awareness, analytical learning and reflective thinking and that in this study, these personal qualities seemingly interacted with guided practices, which resulted in reflective teaching and mastery experience. This, in turn, may very well have brought about improvement in the preservice teachers' personal teaching efficacy during the computer-simulated teaching. [source] Prediction of length of stay for stroke patientsACTA NEUROLOGICA SCANDINAVICA, Issue 1 2007P. Appelros Objectives ,, To examine the factors that influence acute and total length of stay (LOS) for stroke patients. Materials and methods ,, The basis of this investigation was a population-based cohort of first-ever stroke patients (n = 388). Subjects were survivors of the initial hospitalization (n = 295). Age, sex, social factors, risk factors, dementia, stroke type, and stroke severity, measured with the NIH stroke scale (NIHSS), were registered. Results ,, Mean acute LOS was 12 days and mean total LOS was 29 days. Independent predictors of acute LOS were stroke severity, lacunar stroke, prestroke dementia, and smoking. Independent predictors of total LOS were stroke severity and prestroke activities of daily living (ADL) dependency. The NIHSS items that best correlated with LOS were paresis, unilateral neglect and level of consciousness. Conclusions ,, Stroke severity is a strong and reliable predictor of LOS. The results of this study can be used as a baseline for evaluating cost-effectiveness of stroke care changes, e.g. organizational changes or evaluation of new drugs. [source] Extent of extracapsular spreadCANCER, Issue 6 2003A critical prognosticator in oral tongue cancer Abstract BACKGROUND Extracapsular spread (ECS) of metastatic squamous cell carcinoma of the head and neck to regional lymph nodes is the most reliable predictor of poor treatment outcomes. Recently, the authors have shown that ECS is significantly associated with higher rates of locoregional recurrence, distant metastasis, and decreased survival in patients with squamous cell carcinoma of the oral tongue (SCCOT). The purpose of this review was to determine if the degree of ECS impacts distant metastasis rates and survival. METHODS Two hundred sixty-six patients treated for SCCOT with surgery +/, adjuvant radiotherapy from 1980,1995 were reviewed. The setting was a tertiary referral center. The extent of ECS on histopathologic review of involved lymph nodes was measured from the capsular margin to the farthest perinodal extension in mm. Extent of ECS and the number of pathologic lymph nodes with or without ECS were analyzed for disease-free interval, survival rates, and distant metastases. RESULTS No differences in the survival of patients with ECS of , 2 mm or > 2 mm was found (P = 0.92). Patients with both ECS and multiple positive lymph nodes had decreased overall survival (P = 0.0003), disease-specific survival (P = 0.0005), and a shorter disease-free interval (P = 0.019) when compared with those with a single positive lymph node with ECS. Those with multiple ECS+ lymph nodes had the worst prognosis (P = 0.001). CONCLUSIONS Based on these findings, the authors recommended that all patients with SCCOT with ECS or multiple positive lymph nodes with or without ECS on pathologic review be considered for clinical trials that intensify regional and systemic adjuvant therapy. Cancer 2003;97:1464,70. © 2003 American Cancer Society. DOI 10.1002/cncr.11202 [source] Magnetic resonance imaging at term and neuromotor outcome in preterm infantsACTA PAEDIATRICA, Issue 3 2000AM Valkama In order to evaluate the value of neonatal brain magnetic resonance imaging (MRI) for predicting neuromotor outcome in very low birthweight (VLBW) preterm infants, 51 such infants with gestational age <34 wk underwent brain MRI at term age. Myelination, parenchymal lesions (haemorrhage, leukomalacia, infarction, reduction of white matter), parenchymal lesions without subependymal haemorrhage, ventricular/brain ratios and widths of the extracerebral spaces were assessed. The MRI findings were compared with cranial ultrasound (US) performed at term. Infants' neuromotor development was followed up until 18 mo corrected age. Parenchymal lesions seen in MRI at term predicted cerebral palsy (CP) with 100% sensitivity and 79% specificity, the corresponding figures for US being 67% and 85%, respectively. Parenchymal lesions in MRI, excluding subependymal haemorrhages, predicted CP with a sensitivity of 82% and a specificity of 97%, the corresponding figures for US being 58% and 100%, respectively. Delayed myelination, ventricular/brain ratios and widths of the extracerebral spaces failed to predict CP. Term age is a good time for neuroradiological examinations in prematurely born high-risk infants. Parenchymal lesions seen in MRI are reliable predictors for CP. [source] Creativity and Work Environment in a High-Tech ContextCREATIVITY AND INNOVATION MANAGEMENT, Issue 1 2003Jozée Lapierre Creativity is essential for success in business, especially in the high-tech field where knowledge is the key resource. This study addresses the ways in which creativity is fostered in high-tech organizations. It melds the different perspectives on organizational creativity into one six-dimensional model that defines the creativity work environment. Those dimensions are: work atmosphere; vertical collaboration; autonomy/freedom; respect; alignment; and lateral collaboration. They are valid, reliable predictors of the creativity achieved in high-tech organizations. [source] Whole effluent toxicity testing,usefulness, level of protection, and risk assessmentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2000Peter M. Chapman Abstract The general status of whole effluent toxicity (WET) tests is assessed relative to their generally accepted purpose of identifying, characterizing, and eliminating toxic effects of effluents on aquatic resources. Although WET tests are useful, they are not perfect tools (no perfect tools exist). Imperfections include the innate variability of these tests, due both to biotic and anthropogenic factors; the reality of species differences both between the laboratory and the field and within the field; and differences between the laboratory and the receiving environment. Whole effluent toxicity tests may be overprotective (because of their conservative nature, the absence of environmental and ecological processes that could ameliorate exposure, and sensitivity to noncontaminant effects), underprotective (because the most sensitive species cannot be tested, multiple stresses tend to be present in the receiving environment, and failure to account for food chain effects or all possible endpoints), or offer an uncertain level of protection (intermittent doses and mixtures in the environment, adaptations, and hormesis). The implication of hormesis and inverted U-shaped dose responses for WET testing are reviewed in particular detail. Comparisons to field conditions indicate that WET tests are not reliable predictors of effects or lack of effects in the receiving environment. Whole effluent toxicity tests are only the first stage in a risk assessment and as such identify hazard, not risk. Identification of risk requires discarding the concept of independent applicability. The appropriate use of WET tests is identified in the context of their advantages and disadvantages. [source] Reliability of patterns of hippocampal sclerosis as predictors of postsurgical outcomeEPILEPSIA, Issue 9 2010Maria Thom Summary Purpose:, Around one-third of patients undergoing temporal lobe surgery for the treatment of intractable temporal lobe epilepsy with hippocampal sclerosis (HS) fail to become seizure-free. Identifying reliable predictors of poor surgical outcome would be helpful in management. Atypical patterns of HS may be associated with poorer outcomes. Our aim was to identify atypical HS cases from a large surgical series and to correlate pathology with clinical and outcome data. Methods:, Quantitative neuropathologic evaluation on 165 hippocampal surgical specimens and 21 control hippocampi was carried out on NeuN-stained sections. Neuronal densities (NDs) were measured in CA4, CA3, CA2, and CA1 subfields. The severity of granule cell dispersion (GCD) was assessed. Results:, Comparison with control ND values identified the following patterns based on the severity and distribution of neuronal loss: classical HS (CHS; n = 60) and total HS (THS; n = 39). Atypical patterns were present in 30% of cases, including end-folium sclerosis (EFS; n = 5), CA1 predominant pattern (CA1p; n = 9), and indeterminate HS (IHS, n = 35). No HS was noted in 17 cases. Poorest outcomes were noted for no-HS, and CA1p groups with 33,44% International League Against Epilepsy (ILAE) class I at up to 2 years follow-up compared to 69% for CHS (p < 0.05). GCD associated with HS type (p < 0.01), but not with outcome. Conclusions:, These findings support the identification and delineation of atypical patterns of HS using quantitative methods. Atypical patterns may represent distinct clinicopathologic subtypes and may have predictive value following epilepsy surgery. [source] Energy-Containing Nutritional Supplements Can Affect Usual Energy Intake Postsupplementation in Institutionalized Seniors with Probable Alzheimer's DiseaseJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2006Matthew D. Parrott BSc OBJECTIVES: To determine whether increases in caloric intake associated with consumption of a mid-morning nutritional supplement for 3 weeks were maintained in the week after stopping the supplement and to investigate the effects of body mass index (BMI) and cognitive and behavioral measures on this response. DESIGN: Secondary analysis of a previously published randomized, crossover, nonblinded clinical trial. SETTING: A fully accredited geriatric care facility affiliated with the University of Toronto. PARTICIPANTS: Thirty institutionalized seniors with probable Alzheimer's disease (AD) who ate independently. MEASUREMENTS: Investigator-weighed food intake, body weight, cognitive (Severe Impairment Battery; Global Deterioration Scale) and behavioral (Neuropsychiatric Inventory,Nursing Home version; London Psychogeriatric Rating Scale) assessments. RESULTS: Individuals who responded successfully to supplementation as indicated by increases in daily energy intake were likely to maintain 58.8% of that increase postsupplementation, although stopping the supplement was associated with decreased habitual energy intake in low-BMI individuals who reduced their daily intakes during supplementation in response to the extra calories. Cognitive/behavioral tests were not reliable predictors of postsupplement intake. CONCLUSION: Institutionalized seniors with probable AD are likely to alter their usual energy intakes to maintain changes resulting from 3 weeks of supplementation. This effect may allow for rotating supplementation schedules in nursing homes that could reduce staff burden, but only for those individuals who are most likely to respond favorably. These data indicate that nutritional supplements and diet plans should be carefully prescribed in low-BMI individuals to limit variability in total energy provided and thus prevent lower-than-normal intake. [source] Changes in the Episodic Memory and Executive Functions of Abstinent and Relapsed Alcoholics Over a 6-Month PeriodALCOHOLISM, Issue 3 2009Anne Lise Pitel Background:, It is still unclear whether episodic memory and executive functions capacities can return to normal in abstinent patients over a 6-month period. Furthermore, the role of interim drinking in cognitive recovery is still not well known. Finally, further research is required to specify the predictive value of cognitive abilities at initial testing in the treatment outcome (abstinence or relapse). The aims of the present study were therefore to measure changes in episodic memory and executive functions over a 6-month period in abstinent and relapsed alcoholics and to ascertain whether neuropsychological results at treatment entry can predict treatment outcome at follow-up. Methods:, Fifty-four alcoholic patients and 54 matched control subjects performed baseline neuropsychological tasks assessing episodic memory, executive functions, the slave systems of working memory and attentional abilities. At the follow-up session (i.e., 6 months later), episodic memory and 3 executive functions (inhibition, flexibility, and updating) were re-examined in the alcoholic patients. Results:, Results showed that over the 6-month interval, the abstainers' episodic memory and executive performances had returned to normal, whereas the relapsers performed lower than before in the flexibility task. Episodic memory and executive functions recovery was correlated, in abstainers, with drinking history and age respectively. Finally, there was no significant difference regarding neuropsychological scores at baseline between abstainers and relapsers. Discussion:, Over the 6-month interval, abstainers normalized episodic memory and executive performances whereas relapsers obtained executive results which were more severely impaired, emphasizing the influence of interim drinking on cognitive changes. Episodic memory, executive functions, the slave systems of working memory and attentional abilities did not appear to be reliable predictors of treatment outcome over a 6-month interval. [source] | |||||||||||||||||||||||||||||||||||||