Best Indicator (best + indicator)

Distribution by Scientific Domains


Selected Abstracts


Neurological recovery in obstetric brachial plexus injuries: an historical cohort study

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2004
Agnes F Hoeksma MD
An historical cohort study was conducted to investigate the rate and extent of neurological recovery in obstetric brachial plexus injury (OBPI) and to identify possible prognostic factors in a cohort of children with OBPI from birth to 7 years. All children (n=56; 31 females, 25 males) with OBPI were evaluated at fixed time intervals by one examiner. They underwent a final neurological examination at a mean age of 3 years 10 months (range 1 to 7 years). Neurological outcome was not as favourable as is often reported: complete neurological recovery occurred in 37 out of 56 children (66%). In half of these there was delayed recovery, in which case complete neurological recovery was assessed from 1.5 to 16 months of age (median age 6.5 months, SD 4.2 months). External rotation and supination were the last to recover and recovered the least. Although biceps function at three months was considered to be the best indicator for operative treatment, external rotation and supination were found to be better in predicting eventual complete recovery. Initial symptoms directly post partum were not found to be prognostic. Functional outcome was mainly reported to be good. [source]


The meta-analysis of the Italian studies on short-term effects of air pollution (MISA): old and new issues on the interpretation of the statistical evidences

ENVIRONMETRICS, Issue 3 2007
Pierantonio Bellini
Abstract The second meta-analysis of the Italian studies on short-term health effects of air pollution, known as MISA-2, was based on daily time series of indicators of both pollution and of health outcomes. It covered 15 cities during 1996,2002 for a total population of approximately nine millions. Health outcomes included mortality for natural causes, for respiratory diseases and for cardiovascular conditions, as well as hospital admissions for respiratory, cardiac and cerebrovascular diseases. Pollutants considered in univariate analyses were sulphur dioxide (SO2), nitrogen oxide (NO2), carbon monoxide (CO), suspended particulate matter (SPM) measuring less than 10,µm diameter (PM10) and ozone (O3, limited to the summer period). Results, including risk estimates, have been largely confirmatory of findings obtained in previous large meta-analytic studies carried out in North America and in Europe. A full report in Italian is available. The present contribution summarises the results of MISA-2 and addresses three major issues regarding their interpretation: robustness of the causal inferential process, the role of specific air pollutants and the reliability of risk estimates. The former issue is stressed according to Bradford Hill's criteria and the conclusion is reached that at least for the association of air pollution with an increase in mortality the evidence for causality is strong. Assessing the role of each air pollutant is problematic: there is some evidence that the effects of PM10 are partly confounded by other pollutants, but PM10 may not be the best indicator of the role of air SPM (routine measures of PM2.5 have not been introduced in Italy). As for risk estimates, the per cent increase in risk of mortality for unit increase in PM10 concentration, measured in MISA-2, is remarkably similar to estimates in other studies and there is indication for linearity of the dose,response relationship. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Calorimetric study of milk fat/rapeseed oil blends and their interesterification products

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2009
Mario Aguedo
Abstract Milk fat (MF) and rapeseed oil (RO) blends were analyzed by differential scanning calorimetry (DSC). It was shown that peak and onset temperatures can be used to determine the percentage of each fat in the blend and that the relative enthalpy of one peak assigned to low-melting triacylglycerols (TAG) can also be used to determine the percentage of RO in the blend. A linear relation was also established between MF content of the blend and its dropping point (DP), indicating that DP can be linearly related with the above DSC data. A blend of MF/RO 70,:,30 (wt/wt) was then chosen as a model system for enzymatic interesterification (EIE). The applicability of DSC analyses to EIE products was checked and a correct correlation could be established between DSC values and the interesterification degree and DP. Among the data from the DSC profiles, the peak associated with low-melting TAG was the best indicator of the reaction course. In the same way, a high-melting MF stearin fraction was interesterified with RO. In that case, onset temperatures and peak "a" were better reaction indicators than for the interesterified MF/RO blend. We therefore suggest that values from DSC endotherms could be used to monitor EIE of fat blends. [source]


Nitrate leaching from cut grassland as affected by the substitution of slurry with nitrogen mineral fertilizer on two soil types

GRASS & FORAGE SCIENCE, Issue 1 2010
J. J. Schröder
Abstract A field experiment was conducted to find out whether there is any difference in risk of N leaching to groundwater when cattle slurry and/or mineral fertilizer-N was applied to cut grassland. The experiment was carried out over two consecutive years on two sites (one with a relatively wet sandy soil and one with a relatively dry sandy soil). Treatments were mineral fertilizer-N at annual rates of 0,510 kg N ha,1 year,1 and combinations of sod-injected cattle slurry (85, 170, 250 and 335 kg N ha,1 year,1) and mineral fertilizer-N (289, 238, 190 and 139 kg N ha,1 year,1). Yield responses indicated that in the short run, 0·44,0·88 (average 0·60) of the slurry-N was as available as mineral fertilizer-N. The total N input from mineral fertilizer and slurry was a worse predictor of nitrate leaching ( 0·11) than the N surplus (i.e. the difference between total N input and harvested N) ( 0·60). The effective N surplus, based on the difference between the summed inputs of the plant-available N and harvested N, proved to be the best indicator of leaching ( 0·86). Annual N application rates of up to 340 kg plant-available N ha,1 complied with the target nitrate concentration in groundwater of 11·3 mg N L,1 set by the European Union in both years on the wet sandy soil, whereas on the dry sandy soil none of the treatments did. [source]


Inverse Modeling of Coastal Aquifers Using Tidal Response and Hydraulic Tests

GROUND WATER, Issue 6 2007
Andrés Alcolea
Remediation of contaminated aquifers demands a reliable characterization of hydraulic connectivity patterns. Hydraulic diffusivity is possibly the best indicator of connectivity. It can be derived using the tidal response method (TRM), which is based on fitting observations to a closed-form solution. Unfortunately, the conventional TRM assumes homogeneity. The objective of this study was to overcome this limitation and use tidal response to identify preferential flowpaths. Additionally, the procedure requires joint inversion with hydraulic test data. These provide further information on connectivity and are needed to resolve diffusivity into transmissivity and storage coefficient. Spatial variability is characterized using the regularized pilot points method. Actual application may be complicated by the need to filter tidal effects from the response to pumping and by the need to deal with different types of data, which we have addressed using maximum likelihood methods. Application to a contaminated artificial coastal fill leads to flowpaths that are consistent with the materials used during construction and to solute transport predictions that compare well with observations. We conclude that tidal response can be used to identify connectivity patterns. As such, it should be useful when designing measures to control sea water intrusion. [source]


Extending the Efficacy of a Thermal Biofeedback Treatment Package to the Management of Tension-type Headaches in Children

HEADACHE, Issue 2 2001
Richard E. Arndorfer PhD
This study explored the efficacy of a thermal biofeedback treatment package as an intervention with children with tension-type headaches. In a within-subject, time-lagged, multiple baseline design, five children, aged 8 to 14 years, were assigned to baselines of varying lengths prior to receiving treatment. Treatment was introduced sequentially across subjects and involved six thermal biofeedback treatment visits. Parents were also given guidelines for how best to encourage children to independently use the biofeedback skills. Data confirm that the participants learned the handwarming skill, practiced the skill on a regular basis during treatment, and independently used the skills to manage their pain. All participants demonstrated clinically significant reductions in one or more headache parameters (frequency, duration, intensity) following treatment. At 6-month follow-up, four of the five participants were headache-free. Although the thermal biofeedback treatment package was generally effective for these children with tension-type headaches, the specific type of headache experienced by each child appeared to influence the specific response to treatment. In addition, no single measure of headache activity was the best indicator of response to treatment. The efficacy of the thermal biofeedback treatment package is supported as an alternative treatment for children suffering from tension-type headaches. [source]


Evaluation of pre-operative anxiety and propofol-induced sedation using newly proposed indices of finger vascular tone

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 2 2002
Gohichi Tanaka
Abstract: This study examined estimates of finger vascular tone, obtained from photoplethysmography. Normalized and double-normalized pulse volume (NPV and DNPV), blood volume (BV), and pulse volume (PV) were obtained in 2 male and 7 female middle-aged patients at an outpatient office 1,3 days before an operation and in the operating room before and after anesthesia by propofol. There was a preoperative decrease in NPV, and the propofol injection yielded a moderate increase in BV. The latter seemed to contribute to a decrease in DNPV. A partial correlation controlling for body mass index was observed between the change in NPV and the dose of propofol; a larger reduction in NPV before anesthesia compared with the control condition was accompanied by the need for a greater infusion of propofol for sedation. In conclusion, among the measures examined, NPV appears to be the best indicator of heightened arteriolar vascular tone. [source]


EFFECT OF THAWING METHODS ON TEXTURAL QUALITY OF SOUS-VIDE STEWED BEEF ASSESSED BY SENSORY AND INSTRUMENTAL ANALYSES

JOURNAL OF FOOD QUALITY, Issue 5 2001
N.J.N. YAU
ABSTRACT This study compared four different thawing methods using sensory test with magnitude estimation, preference test with hedonic scale and physical analyses. The four methods were tap-water, refrigeration, microwave reheating, and boiling-water reheating. For physical analyses, there were differences (p,0.001) among treatments in drip loss and expressible juice. For drip loss, the microwave reheated samples were the highest and the refrigeration and tap-water treated samples were the lowest. For expressible juice, tap-water and refrigerated samples were higher (p,0.01) than the microwave and boiling-water reheated samples. Microwave and boiling-water reheated samples had higher hardness and cheviness and lower juiciness and fiber-looseness. The refrigerated and tap-water thawed samples had reverse sensory properties. Naive panelists preferred the refrigerated and tap-water treated samples to the microwave and boiling-water reheated samples for juiciness, tenderness, and overall preference. Physical parameters from textural profile analysis were not different among the thawing methods. Expressible juice was the best indicator for sensory hardness, juiciness, fiber-looseness and chewiness among the physical parameters. Usually a quadratic regression model fit best when expressible juice was used to predict sensory textural properties. [source]


Soil- and plant-based nitrogen-fertilizer recommendations in arable farming

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2005
Hans-Werner Olfs
Abstract Under- as well as overfertilization with nitrogen (N) will result in economic loss for the farmer due to reduced yields and quality of the products. Also from an ecological perspective, it is important that the grower makes the correct decision on how much and when to apply N for a certain crop to minimize impacts on the environment. To aggravate the situation, N is a substance that is present in many compartments in different forms (nitrate, ammonium, organic N, etc.) in the soil-plant environment and takes part in various processes (e.g., mineralization, immobilization, leaching, denitrification, etc.). Today, many N-recommendation systems are mainly based on yield expectation. However, yields are not stable from year to year for a given field. Also the processes that determine the N supply from other sources than fertilizer are not predictable at the start of the growing season. Different methodological approaches are reviewed that have been introduced to improve N-fertilizer recommendations for arable crops. Many soil-based methods have been developed to measure soil mineral N (SMN) that is available for plants at a given sampling date. Soil sampling at the start of the growing period and analyzing for the amount of NO -N (and NH -N) is a widespread approach in Europe and North America. Based on data from field calibrations, the SMN pool is filled up with fertilizer N to a recommended amount. Depending on pre-crop, use of organic manure, or soil characteristics, the recommendation might be modified (±10,50,kg N ha,1). Another set of soil methods has been established to estimate the amount of N that is mineralized from soil organic matter, plant residues, and/or organic manure. From the huge range of methods proposed so far, simple mild extraction procedures have gained most interest, but introduction into practical recommendation schemes has been rather limited. Plant-analytical procedures cover the whole range from quantitative laboratory analysis to semiquantitative "quick" tests carried out in the field. The main idea is that the plant itself is the best indicator for the N supply from any source within the growth period. In-field methods like the nitrate plant sap/petiole test and chlorophyll measurements with hand-held devices or via remote sensing are regarded as most promising, because with these methods an adequate adjustment of the N-fertilizer application strategy within the season is feasible. Prerequisite is a fertilization strategy that is based on several N applications and not on a one-go approach. Boden- und Pflanzenanalyse zur Stickstoff-Düngebedarfsprognose in Ackerkulturen Unter- und Überdüngung mit N führen zu deutlichen ökonomischen Verlusten für Landwirte, da sowohl der Ertrag als auch die Qualität der Erzeugnisse vermindert werden. Auch aus ökologischer Sicht ist die richtige Entscheidung des Anbauers über Höhe und Zeitpunkt der N-Düngung von Bedeutung, um die Auswirkungen auf die Umwelt so gering wie möglich zu halten. Erschwerend kommt hinzu, dass N in sehr vielen Umweltkompartimenten in verschiedenen Bindungsformen (Nitrat, Ammonium, organisch gebundener N) vorkommt und dass N in verschiedenste Umsetzungsprozesse involviert ist (Mineralisation, Immobilisation, Auswaschung, Denitrifikation). Auch heutzutage orientieren sich viele Systeme, die zur N-Düngebedarfsprognose eingesetzt werden, im Wesentlichen an der Ertragserwartung. Dabei ist jedoch zu bedenken, dass weder der Ertrag als von Jahr zu Jahr stabil angesehen werden kann, noch dass die Prozesse, die das bodenbürtige N-Angebot bestimmen, zu Beginn der Vegetationsperiode hinreichend gut vorausgesagt werden können. Daher werden im Folgenden verschiedene methodische Ansätze erläutert, die zur Verbesserung der N-Düngebedarfsprognose für Ackerkulturen geeignet erscheinen. Viele Bodenanalyse-Methoden zielen darauf ab, den mineralischen N-Vorrat des Bodens, der an einem bestimmten Beprobungstermin als pflanzenverfügbarer N vorliegt, zu erfassen. Die Bodenprobeentnahme zu Beginn der Vegetationsperiode und die Bestimmung der Menge an Nitrat (und Ammonium) ist ein in Europa und Nord-Amerika weitverbreiteter Ansatz. Anhand der Daten aus Kalibrierversuchen kann dann abgeleitet werden, wie viel Dünger-N zum Auffüllen des N-Vorrats eingesetzt werden soll. In Abhängigkeit von Vorfrucht, Einsatz von Wirtschaftsdüngern oder weiteren Bodeneigenschaften kann diese Empfehlung modifiziert werden (± 10 bis 50,kg N ha,1). Weitere Bodenuntersuchungsmethoden wurden entwickelt, um die Menge des während der Vegetationszeit aus der organischen Bodensubstanz, aus Ernteresten und/oder aus Wirtschaftsdüngern mineralisierten N zu bestimmen. Obwohl aus der Vielzahl der vorgeschlagenen Methoden einfache "milde" Extraktionsverfahren eine gewisse Bedeutung erlangt haben, werden diese in der Praxis bei der Ermittlung des N-Düngebedarfs als zusätzliche Information nur selten berücksichtigt. Verfahren der Pflanzenanalyse umfassen einen weiten Bereich von quantitativen Laboranalysen bis zu halbquantitativen Schnelltests, die direkt auf dem Acker eingesetzt werden können. Die wesentliche Idee beim Einsatz der Pflanzenanalyse ist die Vorstellung, dass die Pflanze an sich der beste Indikator ist, die N-Verfügbarkeit aus den verschiedenen Quellen gewissermaßen kumulativ innerhalb der Wachstumszeit anzuzeigen. Methoden, die auf dem Acker eingesetzt werden können, wie z.,B. der Nitrat-Pflanzensaft- (oder Blattstiel-)Test sowie die Chlorophyll-Messung mit Handgeräten oder berührungslose Messverfahren haben den klaren Vorteil, dass sie eine schnelle Anpassung der N-Düngestrategie während der Vegetation ermöglichen. Voraussetzung dazu ist allerdings, dass die N-Düngestrategie nicht auf einer Einmal-Applikation beruht, sondern dass die N-Düngermenge auf mehrere Teilgaben verteilt wird. [source]


CONSUMER PERCEPTION OF SANDINESS IN DULCE DE LECHE

JOURNAL OF SENSORY STUDIES, Issue 2 2008
ANA GIMÉNEZ
ABSTRACT Sandiness, one of the most common defects of dulce de leche, is caused by lactose crystallization. In order to study consumer reaction to the presence of different levels of this defect, survival analysis statistics was applied to the consumer acceptance/rejection data of the samples. Limits for this defect were estimated by working with 10% and 25% consumer rejection probabilities. The consumers were also asked to score the sample sandiness according to their perception, using a 9-point scale. Cluster analysis and correspondence analysis performed showed the heterogeneity of the consumer responses toward sandiness in dulce de leche. Significant correlations were established between consumer sandiness and the number of crystals and sandiness as measured by a panel of trained assessors, the latter being the best indicator of sandiness as perceived by the consumers. It could be established that the consumers' and assessors' sandiness perception is clearly influenced by the presence of agglomerates, their size distribution and number. PRACTICAL APPLICATIONS Sandiness is an important defect for a segment of consumers who rejected samples with high levels of sandiness, suggesting the importance of avoiding the occurrence of this defect. Survival analysis methodology was used to estimate the maximum level of sandiness in dulce de leche before consumers reject it. As sandiness is a sensory defect that often limits the shelf life of dulce de leche, the calculated sensory limits could be used in future studies to estimate the sensory shelf life of dulce de leche. [source]


Diagnostic imaging of hepatocellular carcinoma in patients with cirrhosis before liver transplantation

LIVER TRANSPLANTATION, Issue S2 2006
Bachir Taouli
Key Concepts: 1The lack of whole-liver explant correlation has led to an overestimation of the sensitivity of imaging tests for the diagnosis of HCC in the radiological literature. 2Ultrasound is insensitive for the diagnosis of HCC in the cirrhotic liver and should not be used for the detection of focal liver lesions in this setting. 3Although magnetic resonance (MR) imaging is more sensitive than multidetector 3-phase computed tomography (CT) for the diagnosis of regenerative and dysplastic nodules it is probably no better than CT for detection of HCC and has a lower false-positive rate. 4Approximately 10,30% of nodules measuring <2 cm seen only on the hepatic arterial phase at CT or MR imaging represent small HCC and vigilant surveillance imaging is required as interval growth is the best indicator of malignancy. Liver Transpl 12:S1,S7, 2006. © 2006 AASLD. [source]


Further uses of the heat of oxidation in chemical hazard assessment

PROCESS SAFETY PROGRESS, Issue 1 2003
Laurence G. Britton
Flammability: The "net heat of oxidation" technique described in an earlier publication is extended to predicting the lower flammable limits, lower limit flame temperatures, and limiting oxygen concentrations of chlorinated organic fuels having H:Cl ratios greater than unity. A new Rule is derived for predicting the effect of initial temperature on the lower flammable limits and limiting oxygen concentrations of organic fuels. It is suggested that this Rule be used in preference to the modified "Burgess-Wheeler" Rule. The effect of initial pressure is discussed. Instability: Net heats of oxidation (kcal/mol oxygen) for a series of disparate fuel groups are compared with ",HD," the maximum heat of decomposition (cal/g) calculated using CHETAH methodology. Given the reasonable assumption that CHETAH's "maximum heat of decomposition" cannot exceed the net heat of combustion ",HC," examination is made as to whether the ratio of these parameters (each expressed in units of kcal/mol), coined the "Reaction Heat Ratio" (RH), provides a useful new indicator for instability assessment. Of these parameters, the net heat of oxidation (,HC/S) is the best indicator to help assign NFPA Instability Ratings. However, ,HC/S cannot generally be used to assign ratings for organo-peroxides. Also, its performance as an indicator for hazardous polymerization depends on the ,HC/S difference between the reacting monomer and the polymer product, so it should become increasingly unreliable as the monomer ,HC/S approaches -100 kcal/mol oxygen. The ranking method tacitly assumes organic polymers to have a constant heat of oxidation of about -100 kcal/mol oxygen. Errors in this assumption must invalidate the ranking approach where ,HC/S differences are small. Finally, separate "cut-offs" must be used at each NFPA Instability Rating for organo-nitrates versus other organics containing combinations of CHON atoms. Additional materials need to be examined to extend this preliminary analysis. The net heat of oxidation would be a useful additional output parameter of the CHETAH program, if only for its application in flammability assessment. No conclusions are drawn regarding the usefulness of net heat of oxidation or RH in conducting CHETAH hazard assessments, since this procedure requires consideration of several variables. However, the analysis may be helpful to the ASTM E 27.07 subcommittee responsible for developing the program. For example, the -,HD , 700 cal/g cut-off used to assign a "high" CHETAH hazard rating typically corresponds to organic materials rated NFPA 1, the second to lowest hazard rating. [source]


The effect of heart rate variability on request for labour epidural analgesia

ANAESTHESIA, Issue 8 2009
H.-C. Lao
Summary Maternal heart rate variability of 62 parturients were compared based on their choice of using (epidural group, 44 women) or not using (control, 18 women) epidural analgesia. Baseline heart rate variability and visual analogue scores were recorded when the cervix of the parturient dilated to 2,4 cm, and paired data were collected 1 h later. We found that parturients in the epidural group had greater heart rate variability at the beginning of labour. Multiple logistic regression analysis identified percentage of absolute difference in successive RR intervals exceeding 20 ms as the best indicator of choosing epidural analgesia. Almost all heart rate variability measures were unchanged 1 h later in both groups. We concluded that parturients who chose epidural analgesia had greater heart rate variability, and that percentage of absolute difference in successive RR intervals exceeding 20 ms could reflect their likelihood of requesting epidural analgesia at the beginning of labour. [source]


Myopisation: The refractive tendency in teenagers.

ACTA OPHTHALMOLOGICA, Issue 2 2000
Prevalence of myopia among young teenagers in Sweden
ABSTRACT. Purpose: 1045 children between 12 and 13 years old were examined in a field study in the Göteborg area (Sweden). The aim of this study was to report the prevalence of refractive errors, with special attention to myopia, since there are no previous reports in Sweden about this age group. Methods: The examination included visual acuity testing and refraction under cycloplegia. Results: We found a prevalence of myopia (,,0.5D) of 49.7% and a prevalence of bilateral myopia of 39%. In the whole population, 23.3% were considered to need glasses (,,0.75D). We also found a prevalence of high myopia (,,5D) in 2.5% of the children. Discussion: No statistically significant difference in myopia with respect to gender was found. The proportion of children needing glasses is considered the best indicator of the prevalence of myopia in this sample. The results confirm that this tendency towards myopisation in a teenage population in Göteborg is similar to the prevalence found in other parts of the world. [source]


Characteristics of Heart Rate Variability Can Predict Impending Septic Shock in Emergency Department Patients with Sepsis

ACADEMIC EMERGENCY MEDICINE, Issue 5 2007
Wei-Lung Chen MD
ObjectivesTo determine whether heart rate variability (HRV) measures can be used to predict which septic patients in the emergency department (ED) will progress to septic shock. MethodsThe authors prospectively enrolled consecutive patients who met the 2001 International Sepsis Definitions Conference criteria of sepsis and visited the ED of a university teaching hospital over a six-month period. In addition to the septic workup, a continuous 10-minute electrocardiogram recording was performed at the same time. The HRV measures were calculated off-line and correlated with the outcome of the patients. ResultsEighty-one patients aged 30,84 years who met the inclusion criteria were enrolled. The patients were classified as those with no septic shock (n= 60) and those with septic shock (n= 21), according to their outcome within six hours. The baseline root mean square successive difference, high-frequency power, and normalized high-frequency power of the septic shock group were significantly higher than those of the no septic shock group. The low-frequency power, normalized low-frequency power, and low-/high-frequency power ratio of the septic shock group were significantly lower than those of the no septic shock group. Multiple logistic regression analysis identified root mean square successive difference as the best predictor of impending septic shock for septic ED patients. ConclusionsHRV measures may be used to identify septic ED patients with impending septic shock. Among those HRV measures, root mean square successive difference seems to be the best indicator to predict the occurrence of septic shock. [source]


Logistic mixture of multivariate regressions for analysis of water quality impacted by agrochemicals

ENVIRONMETRICS, Issue 5 2007
Yongsung Joo
Abstract In this paper, we study the impacts of two representative agricultural activities, fertilizers and lime application, on water quality. Because of heavy usage of nitrogen fertilizers, nitrate (NO) concentration in water is considered as one of the best indicators for agricultural pollution. The mixture of normal distributions has been widely applied with (NO) concentrations to cluster water samples into two environmentally interested groups (water impacted by agrochemicals and natural background water groups). However, this method fails to yield satisfying results because it cannot distinguish low-level fertilizer impact and natural background noise. To improve performance of cluster analysis, we introduce the logistic mixture of multivariate regressions model (LMMR). In this approach, water samples are clustered based on the relationships between major element concentrations and physicochemical variables, which are different in impacted water and natural background water. Copyright © 2006 John Wiley & Sons, Ltd. [source]


The use of SST and SOI anomalies as indicators of crop yield variability

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2009
Maria I. Travasso
Abstract Interannual climate variability accounts for most of the observed crop yield fluctuations in the main agricultural region of Argentina. Moreover, in this region climatic variations are related to sea surface temperatures (SST) and the Southern Oscillation Index (SOI). In the present study, we aimed to obtain indicators of crop yield variability based on these drivers. For this purpose, monthly anomalies corresponding to SSTs from the Equatorial Pacific (SSTN3) and South Atlantic (SSTSA) Oceans and the SOI were related to maize, sunflower and soybean grain yield anomalies. Historical data (1923,2000 for maize, 1934,2000 for sunflower and 1969,2000 for soybean) were used to obtain grain yield anomalies at the county level after removing technology trends by smoothing techniques. By means of correlation analysis, we obtained the counties presenting significant association (p < 0.05) between monthly SST/SOI anomalies and yield anomalies, for the period 1950,1997. Those indicators showing spatial consistency were classified in percentiles, and the values corresponding to the upper and lower terciles showed to be useful to discriminate between positive and negative yield anomalies (high and low yields). In general, SOI for maize and SSTSA for soybean and sunflower were the best indicators of crop yield variability. SOI corresponding to September and May were useful in counties contributing to 71% of maize production. SSTa_SA (June) was the best for soybean in the main producing region, which includes 72% of the total production. SSTa_SA (March) could be useful for sunflower in the northern part of the region, which accounts for 27% of the regional production. Copyright © 2008 Royal Meteorological Society [source]


Histopathological features and accuracy for diagnosing biliary atresia by prelaparotomy liver biopsy in developing countries

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 1 2009
Archana Rastogi
Abstract Background and Aim:, A major challenge in neonatal cholestasis (NC) is to differentiate biliary atresia (BA) from other non-atretic causes. In developing countries there are considerable problems of late referral of NC cases and performing surgery without prelaparotomy liver biopsy that contributes to a high proportion of negative laparotomy and increased morbidity. We evaluated the hepatic histopathology for presence of features that correlate best with the diagnosis of BA and assessed the accuracy of percutaneous liver biopsy. Methods:, Fifty-five cases of NC that fulfilled the selection criteria and had liver biopsy available were analyzed. Among the 49 adequate liver biopsies, 28 cases were diagnosed as BA, 15 neonatal hepatitis (NH) and 6 were due to other causes. Validity of percutaneous liver biopsy diagnoses was compared with confirmed cases by laparotomy findings and 1-year follow up. Twelve histological parameters of confirmed cases of BA and NH were evaluated by logistic regression analyses. Results:, Ductular proliferation (P = 0.0002), bile duct and ductular bile plugs (P = 0.009), and portal fibrosis (P = 0.002) were the best indicators of BA and among them ductular proliferation was the most important in distinguishing BA from NH. Ductal plate malformation was observed in 17.9% cases of BA. Sensitivity and specificity of percutaneous liver biopsy for diagnosing BA was 88.2% each. Conclusion:, Percutaneous liver biopsy is highly accurate (88.2%) in diagnosing BA. In developing countries. This investigation should be done to decrease the frequency of negative laparotomy and to achieve cost,benefit with reduced morbidity. [source]


Reaction of Cotton Cultivars and an F2 Population to Stem Inoculation with Isolates Verticillium dahliae

JOURNAL OF PHYTOPATHOLOGY, Issue 5 2005
Y. Bolek
Abstract Four Verticillium dahliae isolates (V76, TS-2, PH, and V44) were used in screening four cotton cultivars (Pima S-7, Acala Prema, M-315 and Acala 44). Pima S-7 and Acala Prema gave the highest resistance reactions and Acala 44 was the most susceptible. Isolate V76 of V. dahliae was the most virulent. An interspecific cross between the resistant cv Pima S-7 (Gossypium barbadense) and the susceptible cv. Acala 44 (G. hirsutum) was made and the F2 population phenotyped for Verticillium wilt effect. Phenotyping of plant reaction to the disease was quantified by using a set of six growth parameters (number of healthy leaves, number of nodes, leaf weight, stem weight, leaf to stem ratio, and total shoot weight) measured 3 weeks after inoculation. The F2 phenotypic distribution of these parameters suggests that distribution is towards resistance and polygenic. Transgressive segregation also was observed. The number of healthy leaves and total shoot weight were found to be the best indicators of resistance. Results obtained in this study will be useful to quantify resistance to V. dahliae and identify the best parameters to phenotype in genetic studies. [source]


Water Framework Directive: ecological classification of Danish lakes

JOURNAL OF APPLIED ECOLOGY, Issue 4 2005
MARTIN SØNDERGAARD
Summary 1The European Water Framework Directive (WFD) requires that all European waterbodies are assigned to one of five ecological classes, based primarily on biological indicators, and that minimum good ecological quality is obtained by 2015. However, the directive provides only general guidance regarding indicator definitions and determination of boundaries between classes. 2We used chemical and biological data from 709 Danish lakes to investigate whether and how lake types respond differently to eutrophication. In the absence of well-defined reference conditions, lakes were grouped according to alkalinity and water depth, and the responses to eutrophication were ordered along a total phosphorus (TP) gradient to test the applicability of pre-defined boundaries. 3As a preliminary classification we suggest a TP-based classification into high, good, moderate, bad and poor ecological quality using 0,25, 25,50, 50,100, 100,200 and > 200 µg P L,1 boundaries for shallow lakes, and 0,12·5, 12·5,25, 25,50, 50,100 and > 100 µg P L,1 boundaries for deep lakes. Within each TP category, median values are used to define preliminary boundaries for the biological indicators. 4Most indicators responded strongly to increasing TP, but there were only minor differences between low and high alkalinity lakes and modest variations between deep and shallow lakes. The variability of indicators within a given TP range was, however, high, and for most indicators there was a considerable overlap between adjacent TP categories. Cyanophyte biomass, submerged macrophyte coverage, fish numbers and chlorophyll a were among the ,best' indicators, but their ability to separate different TP classes varied with TP. 5When using multiple indicators the risk that one or more indicators will indicate different ecological classes is high because of a high variability of all indicators within a specific TP class, and the ,one out , all out' principle in relation to indicators does not seem feasible. Alternatively a certain compliance level or a ,mean value' of the indicators can be used to define ecological classes. A precise ecological quality ratio (EQR) using values between 0 and 1 can be calculated based on the extent to which the total number of indicators meets the boundary conditions, as demonstrated from three Danish lakes. 6Synthesis and applications. The analysis of Danish lakes has identified a number of useful indicators for lake quality and has suggested a method for calculating an ecological quality ratio. However, it also demonstrates that the implementation of the Water Framework Directive faces several challenges: gradual rather than stepwise changes for all indicators, large variability of indicators within lake classes, and problems using the one out , all out principle for lake classification. [source]