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Standard Means (standard + mean)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Abnormalities in the coordination of respiration and swallow in preterm infants with bronchopulmonary dysplasia

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2006
Ira H Gewolb MD
Individual rhythms of suck, swallow, and respiration are disrupted in preterm infants with bronchopulmonary dysplasia (BPD). Integration of respiration into suck-swallow efforts is critical for establishing coordinated suckle feeding. This study quantitatively assessed the coordination of respiration and swallow in infants with and without BPD. Thirty-four preterm infants of 26 to 33 weeks'gestational age were included: 14 participants with BPD (eight males, six females) and 20 comparison participants without BDP (10 males, 10 females). Participants were studied at postmenstrual age 32 to 40 weeks and postnatal age 2 to 12 weeks using digital recordings of pharyngeal pressure, nasal thermistor flow, and thoraco-abdominal plethysmography. The coefficients of variation (COV; standard deviation/mean) of the swallow-breath (SW-BR) and breath-breath (BR-BR) intervals during swallow runs, the percentage of,apneic swallows'(runs of ,3 swallows without interposed breaths), and phase relationships of respiration and swallow were used to quantify rhythmic coordination and integration of respiration into feeding episodes. Apneic swallows were significantly increased after 35 weeks in infants with BPD (mean 13.4% [SE 2.4]) compared with non-BDP infants (6.7% [SE 1.8];p < 0.05), as were SW-BR phase relationships involving apnea. The BPD cohort also had significantly higher SW-BR COV and BR-BR COV than non-BPD infants, indicating less rhythmic coordination of swallowing and respiration during feeding. Results emphasize the need for frequent rests and closer monitoring when feeding infants with respiratory compromise. Quantitative assessment of the underlying rhythms involved in feeding may be predictive of longer-term feeding and neurological problems. [source]

Distribution of myrmecochorous species over the landscape and their potential long-distance dispersal by emus and kangaroos

DIVERSITY AND DISTRIBUTIONS, Issue 1 2008
María Calviño-Cancela
ABSTRACT Topographical heterogeneity can create a mosaic of substrate types leading to the formation of isolated plant populations. Seed dispersal then becomes crucial for the colonization of such suitable but remote substrate types. We surveyed the distribution of seven elaiosome-bearing species (myrmecochores) over 5 km2 of natural heathland in southwestern Australia. Ants are the standard means of dispersal of these species, which provide limited dispersal (usually of a few metres). Six species were associated with particular substrate types (dune or swale) and all occurred as discrete populations, on average 270,500 m apart, with closest dune edges 280 m apart. We evaluated the possible roles of emus and kangaroos as alternative agents of long-distance seed dispersal between substrate types. Their droppings contained viable seeds of three of the target species, as well as other myrmecochores, and were evenly distributed over the substrate types. While migration of these plant species between preferred substrate types seems unlikely when considering only their standard dispersal agents (ants), it is highly likely in the presence of emus (in particular) and kangaroos that act as non-standard dispersers. This may have important consequences for plant species conservation by increasing habitat connectivity and favouring regional persistence. [source]

Proximal Isovelocity Surface Area (PISA) in the Evaluation of Fixed Membranous Subaortic Stenosis

ECHOCARDIOGRAPHY, Issue 2 2002
Gregory M. Goodkin M.D.
The evaluation of the severity of subaortic stenosis is usually expressed by the magnitude of the subvalvular gradient. Calculation of the membrane orifice area noninvasively is difficult by the standard means. We present a patient in whom the area was calculated using the proximal isovelocity surface area (PISA) method. This method should have clinical applicability because it is not flow dependent and can be used in patients with normal, reduced, or increased stroke volume. [source]

German Exchange Rate Exposure at DAX and Aggregate Levels, International Trade and the Role of Exchange Rate Adjustment Costs

GERMAN ECONOMIC REVIEW, Issue 3 2007
Horst Entorf
Exchange rate exposure; macroeconomic risks; financial panel econometrics Abstract. This article analyses value changes of German stock market companies in response to movements of the US dollar. The approach followed in this work extends the standard means of measuring exchange rate exposure in several ways, e.g. by using multifactor modelling instead of augmented Capital Asset Pricing Model, application of moving window panel regressions and orthogonalization of overall market risk vis-à-vis currency risk. A further innovation lies in testing the theoretical implications of exchange rate adjustment costs (hedging costs) for firm values and economic exposure. Based on time series and panel data of German Deutsche Aktien Xchange companies, Deutsche Mark/dollar rates and macroeconomic factors, we find a rather unstable, time-variant exposure of German stock market companies. Dollar sensitivity is positively affected by the ratio of exports/gross domestic product (GDP) and negatively affected by imports/GDP. Moreover, as expected from theoretical findings, firm values and exchange rate exposure are significantly reduced by adjustment costs depending on the distance of the exchange rate from the expected long-run mean. [source]

Generalized Additive Models and Lucilia sericata Growth: Assessing Confidence Intervals and Error Rates in Forensic Entomology,

JOURNAL OF FORENSIC SCIENCES, Issue 4 2008
Aaron M. Tarone Ph.D.
Abstract:, Forensic entomologists use blow fly development to estimate a postmortem interval. Although accurate, fly age estimates can be imprecise for older developmental stages and no standard means of assigning confidence intervals exists. Presented here is a method for modeling growth of the forensically important blow fly Lucilia sericata, using generalized additive models (GAMs). Eighteen GAMs were created to predict the extent of juvenile fly development, encompassing developmental stage, length, weight, strain, and temperature data, collected from 2559 individuals. All measures were informative, explaining up to 92.6% of the deviance in the data, though strain and temperature exerted negligible influences. Predictions made with an independent data set allowed for a subsequent examination of error. Estimates using length and developmental stage were within 5% of true development percent during the feeding portion of the larval life cycle, while predictions for postfeeding third instars were less precise, but within expected error. [source]

Moricizine Induced Increase in Pacing Threshold

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p1 2003
JOHN P. GIROD
GIROD, J.P., et al.: Moricizine Induced Increase in Pacing Threshold. A 72-year-old woman who was experiencing incessant ventricular tachycardia and recurrent automatic implantable cardioverter defibrillator (AICD) firing despite amiodarone therapy was referred to the Cleveland Clinic Foundation. Myocardial ischemia and infarction were ruled out by standard means. Several antiarrhythmic medications were tried previously without success. Moricizine, 200 mg three times daily, was initiated and controlled the ventricular tachycardia. However, after the dose of moricizine was titrated upward, the patient became symptomatically bradycardic and the ECG exhibited 2:1 block of her paced rhythm and an increased ventricular pacing threshold. (PACE 2003; 26[Pt. I]:110,111) [source]