Longitudinal intra and inter-individual variability in young swimmers performance and determinant factors

OpenAIRE

Morais, Jorge; Costa, Mário; Moreira, Marc; Forte, Pedro; Silva, António; Marinho, Daniel; Barbosa, Tiago

2014-01-01

The aim of study was to follow-up the intra-individual and inter-individual stability of talented swimmers’ performance and its anthropometrics, kinematics, hydrodynamics and efficiency during two competitive seasons. Thirty talented swimmers (14 boys: 12.33 ± 0.65 years; and 16 girls: 11.15 ± 0.55 years) were followed-up. Performance (100-m freestyle), anthropometrics (body mass, height, arm span, chest perimeter, trunk transverse surface area, hand and foot surface area), kinematics (stroke...

Intra-individual biological variation in sweat chloride concentrations in CF, CFTR dysfunction, and healthy pediatric subjects.

Science.gov (United States)

Cirilli, Natalia; Raia, Valeria; Rocco, Ilaria; De Gregorio, Fabiola; Tosco, Antonella; Salvadori, Laura; Sepe, Angela Ornella; Buzzetti, Roberto; Minicuci, Nadia; Castaldo, Giuseppe

2018-04-02

The sweat test is one of the main diagnostic tools used in newborn screening programs and as a confirmatory test, in case of suspect of Cystic Fibrosis (CF). Since sweat chloride (Cl) concentration is also considered an appropriate parameter to explore the efficacy of CFTR modulators in clinical trials, it is crucial to evaluate the biological variability of this test in healthy and pathological conditions. The aim of this pilot study was to determine the intra-individual biological variability of sweat Cl, both in healthy individuals and CF patients and to assess its correlation with diet, season, and menstrual cycle. Thirty-five out of 36 selected subjects (6-18 years) were enrolled by 2 CF care centers and assigned to 3 cohorts: CF, CFTR-related disorder (CFTR-RD) and healthy volunteers. Each participant was subjected to eight sweat tests in different conditions and time of the year. Data were analyzed using linear mixed effects models for repeated measures, taking also into account intra-individual correlations. We observed a high intra-individual variability of sweat Cl, with the lowest mean CV% values among CF patients (20.21 in CF, 29.74 in CFTR-RD, and 31.15 in healthy subjects). Gender and diet had no influence on sweat Cl variability, nor had pubertal age and menstrual phase. Results of this pilot study confirmed that sweat Cl variability is high in CF patients, although non-CF individuals displayed even higher mean CV% values. Season significantly influenced sweat test values only in CF patients, likely due to changes in their hydration status. © 2018 Wiley Periodicals, Inc.

Endotracheal temperature and humidity measurements in laryngectomized patients: intra- and inter-patient variability

NARCIS (Netherlands)

Scheenstra, R.J.; Muller, S.H.; Vincent, A.; Sinaasappel, M.; Zuur, J.K.; Hilgers, F.J.M.

2009-01-01

This study assesses intra- and inter-patient variability in endotracheal climate (temperature and humidity) and effects of heat and moister exchangers (HME) in 16 laryngectomized individuals, measured repeatedly (N = 47). Inhalation Breath Length (IBL) was 1.35 s without HME and 1.05 s with HME (P <

Endotracheal temperature and humidity measurements in laryngectomized patients: intra- and inter-patient variability

NARCIS (Netherlands)

Scheenstra, R. J.; Muller, S. H.; Vincent, A.; Sinaasappel, M.; Zuur, J. K.; Hilgers, Frans J. M.

2009-01-01

This study assesses intra- and inter-patient variability in endotracheal climate (temperature and humidity) and effects of heat and moister exchangers (HME) in 16 laryngectomized individuals, measured repeatedly (N = 47). Inhalation Breath Length (IBL) was 1.35 s without HME and 1.05 s with HME (P

Intra-individual variability in information processing speed reflects white matter microstructure in multiple sclerosis.

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Mazerolle, Erin L; Wojtowicz, Magdalena A; Omisade, Antonina; Fisk, John D

2013-01-01

Slowed information processing speed is commonly reported in persons with multiple sclerosis (MS), and is typically investigated using clinical neuropsychological tests, which provide sensitive indices of mean-level information processing speed. However, recent studies have demonstrated that within-person variability or intra-individual variability (IIV) in information processing speed may be a more sensitive indicator of neurologic status than mean-level performance on clinical tests. We evaluated the neural basis of increased IIV in mildly affected relapsing-remitting MS patients by characterizing the relation between IIV (controlling for mean-level performance) and white matter integrity using diffusion tensor imaging (DTI). Twenty women with relapsing-remitting MS and 20 matched control participants completed the Computerized Test of Information Processing (CTIP), from which both mean response time and IIV were calculated. Other clinical measures of information processing speed were also collected. Relations between IIV on the CTIP and DTI metrics of white matter microstructure were evaluated using tract-based spatial statistics. We observed slower and more variable responses on the CTIP in MS patients relative to controls. Significant relations between white matter microstructure and IIV were observed for MS patients. Increased IIV was associated with reduced integrity in more white matter tracts than was slowed information processing speed as measured by either mean CTIP response time or other neuropsychological test scores. Thus, despite the common use of mean-level performance as an index of cognitive dysfunction in MS, IIV may be more sensitive to the overall burden of white matter disease at the microstructural level. Furthermore, our study highlights the potential value of considering within-person fluctuations, in addition to mean-level performance, for uncovering brain-behavior relationships in neurologic disorders with widespread white matter pathology.

Estimation of intra-operator variability in perfusion parameter measurements using DCE-US.

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Gauthier, Marianne; Leguerney, Ingrid; Thalmensi, Jessie; Chebil, Mohamed; Parisot, Sarah; Peronneau, Pierre; Roche, Alain; Lassau, Nathalie

2011-03-28

To investigate intra-operator variability of semi-quantitative perfusion parameters using dynamic contrast-enhanced ultrasonography (DCE-US), following bolus injections of SonoVue(®). The in vitro experiments were conducted using three in-house sets up based on pumping a fluid through a phantom placed in a water tank. In the in vivo experiments, B16F10 melanoma cells were xenografted to five nude mice. Both in vitro and in vivo, images were acquired following bolus injections of the ultrasound contrast agent SonoVue(®) (Bracco, Milan, Italy) and using a Toshiba Aplio(®) ultrasound scanner connected to a 2.9-5.8 MHz linear transducer (PZT, PLT 604AT probe) (Toshiba, Japan) allowing harmonic imaging ("Vascular Recognition Imaging") involving linear raw data. A mathematical model based on the dye-dilution theory was developed by the Gustave Roussy Institute, Villejuif, France and used to evaluate seven perfusion parameters from time-intensity curves. Intra-operator variability analyses were based on determining perfusion parameter coefficients of variation (CV). In vitro, different volumes of SonoVue(®) were tested with the three phantoms: intra-operator variability was found to range from 2.33% to 23.72%. In vivo, experiments were performed on tumor tissues and perfusion parameters exhibited values ranging from 1.48% to 29.97%. In addition, the area under the curve (AUC) and the area under the wash-out (AUWO) were two of the parameters of great interest since throughout in vitro and in vivo experiments their variability was lower than 15.79%. AUC and AUWO appear to be the most reliable parameters for assessing tumor perfusion using DCE-US as they exhibited the lowest CV values.

Plasma Beta-Trace Protein as a Marker of Residual Renal Function: The Effect of Different Hemodialysis Modalities and Intra-Individual Variability over Time

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Amaryllis H. van Craenenbroeck

2017-11-01

Full Text Available Background/Aims: Beta-trace protein (BTP is a low-molecular-weight molecule, which may be used to assess residual renal function (RRF in dialysis patients. Here we evaluated the influence of hemodialysis (HD and hemodiafiltration (HDF on plasma BTP, and analyzed the inter- and intra-individual variability of plasma BTP over time in HD and peritoneal dialysis (PD patients. Methods: In 12 prevalent HD patients, the effect of a single session of low-flux HD, high-flux HD and HDF on plasma BTP was studied. Blood samples were taken at baseline, after 120 and 240 minutes, and at the start of the next dialysis session. In 13 HD patients and 10 PD patients, inter- and intra-individual variability over three months was studied (monthly and weekly, respectively. Plasma BTP was measured using a nephelometric method. Results: No significant decrease in plasma BTP was seen following a session of low-flux HD. Both high-flux HD and HDF resulted in a significant decrease immediately after dialysis (22% and 61% median decrease, respectively. A significant reduction of the molecule persisted only in HDF and a significant decrease (-15% was still found immediately before the start of the next dialysis session. In both HD and PD patients, the reproducibility over time was excellent with intra-class correlation coefficient of 0.96 (0.93-0.99 and 0.92 (0.86-0.99 respectively. In a small cohort of PD patients, fair agreement existed between mGFR (average of renal urea and creatinine clearance from a 24 hours urine collection and the BTP-based GFR estimation. Conclusion: BTP is a stable marker and a promising tool for RRF estimations in PD and HD patients. In patients receiving HDF, plasma levels of BTP should be interpreted with caution.

Step-to-step spatiotemporal variables and ground reaction forces of intra-individual fastest sprinting in a single session.

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Nagahara, Ryu; Mizutani, Mirai; Matsuo, Akifumi; Kanehisa, Hiroaki; Fukunaga, Tetsuo

2018-06-01

We aimed to investigate the step-to-step spatiotemporal variables and ground reaction forces during the acceleration phase for characterising intra-individual fastest sprinting within a single session. Step-to-step spatiotemporal variables and ground reaction forces produced by 15 male athletes were measured over a 50-m distance during repeated (three to five) 60-m sprints using a long force platform system. Differences in measured variables between the fastest and slowest trials were examined at each step until the 22nd step using a magnitude-based inferences approach. There were possibly-most likely higher running speed and step frequency (2nd to 22nd steps) and shorter support time (all steps) in the fastest trial than in the slowest trial. Moreover, for the fastest trial there were likely-very likely greater mean propulsive force during the initial four steps and possibly-very likely larger mean net anterior-posterior force until the 17th step. The current results demonstrate that better sprinting performance within a single session is probably achieved by 1) a high step frequency (except the initial step) with short support time at all steps, 2) exerting a greater mean propulsive force during initial acceleration, and 3) producing a greater mean net anterior-posterior force during initial and middle acceleration.

Measurement invariance within and between individuals: a distinct problem in testing the equivalence of intra- and inter-individual model structures.

Science.gov (United States)

Adolf, Janne; Schuurman, Noémi K; Borkenau, Peter; Borsboom, Denny; Dolan, Conor V

2014-01-01

We address the question of equivalence between modeling results obtained on intra-individual and inter-individual levels of psychometric analysis. Our focus is on the concept of measurement invariance and the role it may play in this context. We discuss this in general against the background of the latent variable paradigm, complemented by an operational demonstration in terms of a linear state-space model, i.e., a time series model with latent variables. Implemented in a multiple-occasion and multiple-subject setting, the model simultaneously accounts for intra-individual and inter-individual differences. We consider the conditions-in terms of invariance constraints-under which modeling results are generalizable (a) over time within subjects, (b) over subjects within occasions, and (c) over time and subjects simultaneously thus implying an equivalence-relationship between both dimensions. Since we distinguish the measurement model from the structural model governing relations between the latent variables of interest, we decompose the invariance constraints into those that involve structural parameters and those that involve measurement parameters and relate to measurement invariance. Within the resulting taxonomy of models, we show that, under the condition of measurement invariance over time and subjects, there exists a form of structural equivalence between levels of analysis that is distinct from full structural equivalence, i.e., ergodicity. We demonstrate how measurement invariance between and within subjects can be tested in the context of high-frequency repeated measures in personality research. Finally, we relate problems of measurement variance to problems of non-ergodicity as currently discussed and approached in the literature.

Estimating variation in stomatal frequency at intra-individual, intra-site, and inter-taxonomic levels in populations of the Leonardoxa africana (Fabaceae) complex over environmental gradients in Cameroon

Science.gov (United States)

Finsinger, Walter; Dos Santos, Thibaut; McKey, Doyle

2013-07-01

Variation of stomatal frequency (stomatal density and stomatal index) includes genetically-based, potentially-adaptive variation, and variation due to phenotypic plasticity, the degree of which may be fundamental to the ability to maintain high water-use efficiency and thus to deal with environmental change. We analysed stomatal frequency and morphology (pore length, pore width) in leaves from several individuals from nine populations of four sub-species of the Leonardoxa africana complex. The dataset represents a hierarchical sampling wherein factors are nested within each level (leaves in individuals, individuals in sites, etc.), allowing estimation of the contribution of different levels to overall variation, using variance-component analysis. SI showed significant variation among sites ("site" is largely confounded with "sub-species"), being highest in the sub-species localized in the highest-elevation site. However, most of the observed variance was accounted for at intra-site and intra-individual levels. This variance could reflect great phenotypic plasticity, presumably in response to highly local variation in micro-environmental conditions.

Intra- and inter-individual variability of Aspergillus fumigatus reactive T-cell frequencies in healthy volunteers in dependency of mould exposure in residential and working environment.

Science.gov (United States)

Wurster, Sebastian; Weis, Philipp; Page, Lukas; Helm, Johanna; Lazariotou, Maria; Einsele, Hermann; Ullmann, Andrew J

2017-10-01

Invasive aspergillosis remains a deadly disease in immunocompromised patients, whereas the combination of an exaggerated immune response and continuous exposure lead to various hyperinflammatory diseases. This pilot study aimed to gain an overview of the intra- and inter-individual variability in Aspergillus fumigatus reactive T-helper cells in healthy adults and the correlation with environmental mould exposure. In this flow cytometric study, the frequencies of CD154 + A. fumigatus reactive T cells were evaluated in 70 healthy volunteers. All subjects completed a standardised questionnaire addressing their mould exposure. Subjects with intensive mould exposure in their professional or residential surrounding demonstrated considerably higher mean frequencies of A. fumigatus reactive T-helper and T-memory cells. Comparative evaluation of multiple measurements over time demonstrated relatively conserved reactive T-cell frequencies in the absence of major changes to the exposure profile, whereas those frequently exposed in professional environment or with changes to their risk score demonstrated a marked dependency of antigen reactive T-cell frequencies on recent mould exposure. This pilot study was the first to provide data on the intra-individual variability in A. fumigatus reactive T-cell frequencies and its linkage to mould encounter. Fungus reactive T cells are to be considered a valued tool for the assessment of environmental mould exposure. © 2017 Blackwell Verlag GmbH.

Variability of fasting and post-menthionine plasma homocysteine levels in normo- and hyperhomocysteinaemic individuals

NARCIS (Netherlands)

van den Berg, M.; de Jong, S.C.; Devilli, W.; Rauwerda, J.A.; Jakobs, C.A.J.M.; Pals, G.; Boers, G.H.J.; Stehouwer, C.D.A.

1999-01-01

To assess the variability of plasma homocysteine levels, fasting and post-methionine homocysteine levels were measured twice, at baseline and after follow-up of 1-4 months, in 16 individuals with normal and 26 with elevated homocysteine levels after methionine loading. The intra-individual

Intra-individual variability in the urine concentrations of inhaled salmeterol in male subjects with reference to doping analysis – impact of urine specific gravity correction

DEFF Research Database (Denmark)

Hostrup, Morten; Kalsen, Anders; Hemmersbach, Peter

2012-01-01

and a-hydroxysalmeterol during visits one and two were 12.6 and 21.8%, respectively. The intra-individual variability of salmeterol and a-hydroxysalmeterol in the urine concentrations were significantly higher when uncorrected for USG with 43.0 and 43.7% versus 20.4% (p...Since 2010, the World Anti-Doping Agency (WADA) has introduced urinary thresholds for some beta2-agonists. In doping analysis urine samples of beta2-agonists are not corrected for the Urine Specific Gravity (USG) by the WADA laboratories. Several studies have observed high differences in the urine...

Increased intra-participant variability in children with autistic spectrum disorder: Evidence from single trial analyses of evoked EEG.

Directory of Open Access Journals (Sweden)

Elizabeth eMilne

2011-03-01

Full Text Available Intra-participant variability in clinical conditions such as autistic spectrum disorder (ASD is an important indicator of pathophysiological processing. The data reported here illustrate that trial-by-trial variability can be reliably measured from EEG, and that intra-participant EEG variability is significantly greater in those with ASD than in neuro-typical matched controls. EEG recorded at the scalp is a linear mixture of activity arising from muscle artifacts and numerous concurrent brain processes. To minimise these additional sources of variability, EEG data were subjected to two different methods of spatial filtering. (i The data were decomposed using infomax Independent Component Analysis (ICA, a method of blind source separation which un-mixes the EEG signal into components with maximally independent time-courses, and (ii a surface Laplacian transform was performed (Current Source Density interpolation in order to reduce the effects of volume conduction. Data are presented from thirteen high functioning adolescents with ASD without co-morbid ADHD, and twelve neuro-typical age- IQ- and gender-matched controls. Comparison of variability between the ASD and neuro-typical groups indicated that intra-participant variability of P1 latency and P1 amplitude was greater in the participants with ASD, and inter-trial α-band phase coherence was lower in the participants with ASD. These data support the suggestion that individuals with ASD are less able to synchronise the activity of stimulus-related cell assemblies than neuro-typical individuals, and provide empirical evidence in support of theories of increased neural noise in ASD.

[Inter-and intra-operator variability in the analysis of semen parameters: results from a quality control program].

Science.gov (United States)

Daoud, Salima; Chakroun-Feki, Nozha; Sellami, Afifa; Ammar-Keskes, Leila; Rebai, Tarek

2016-01-01

Semen analysis is a key part of male infertility investigation. The necessity of quality management implementation in the andrology laboratory has been recognized in order to ensure the reliability of its results. The aim of this study was to evaluate intra- and inter-individual variability in the assessment of semen parameters in our laboratory through a quality control programme. Four participants from the laboratory with different experience levels have participated in this study. Semen samples of varying quality were assessed for sperm motility, concentration and morphology and the results were used to evaluate inter-participant variability. In addition, replicates of each semen sample were analyzed to determine intra-individual variability for semen parameters analysis. The average values of inter-participant coefficients of variation for sperm motility, concentration and morphology were 12.8%, 19.8% and 48.9% respectively. The mean intra-participant coefficients of variation were, respectively, 6.9%, 12.3% and 42.7% for sperm motility, concentration and morphology. Despite some random errors of under- or overestimation, the overall results remained within the limits of acceptability for all participants. Sperm morphology assessment was particularly influenced by the participant's level of experience. The present data emphasize the need for appropriate training of the laboratory staff and for regular participation in internal quality control programmes in order to improve the reliability of laboratory results.

On the intra-seasonal variability within the extratropics in the ECHAM3 general circulation model

International Nuclear Information System (INIS)

May, W.

1994-01-01

First we consider the GCM's capability to reproduce the midlatitude variability on intra-seasonal time scales by a comparison with observational data (ECMWF analyses). Secondly we assess the possible influence of Sea Surface Temperatures on the intra-seasonal variability by comparing estimates obtained from different simulations performed with ECHAM3 with varying and fixed SST as boundary forcing. The intra-seasonal variability as simulated by ECHAM3 is underestimated over most of the Northern Hemisphere. While the contributions of the high-frequency transient fluctuations are reasonably well captured by the model, ECHAM3 fails to reproduce the observed level of low-frequency intra-seasonal variability. This is mainly due to the underestimation of the variability caused by the ultra-long planetary waves in the Northern Hemisphere midlatitudes by the model. In the Southern Hemisphere midlatitudes, on the other hand, the intra-seasonal variability as simulated by ECHAM3 is generally underestimated in the area north of about 50 southern latitude, but overestimated at higher latitudes. This is the case for the contributions of the high-frequency and the low-frequency transient fluctuations as well. Further, the model indicates a strong tendency for zonal symmetry, in particular with respect to the high-frequency transient fluctuations. While the two sets of simulations with varying and fixed Sea Surface Temepratures as boundary forcing reveal only small regional differences in the Southern Hemisphere, there is a strong response to be found in the Northern Hemisphere. The contributions of the high-frequency transient fluctuations to the intra-seasonal variability are generally stronger in the simulations with fixed SST. Further, the Pacific storm track is shifted slightly poleward in this set of simulations. For the low-frequency intra-seasonal variability the model gives a strong, but regional response to the interannual variations of the SST. (orig.)

Individual killer whale vocal variation during intra-group behavioral dynamics

Science.gov (United States)

Grebner, Dawn M.

The scientific goal of this dissertation was to carefully study the signal structure of killer whale communications and vocal complexity and link them to behavioral circumstances. The overall objective of this research sought to provide insight into killer whale call content and usage which may be conveying information to conspecifics in order to maintain group cohesion. Data were collected in the summers of 2006 and 2007 in Johnstone Strait, British Columbia. For both individuals and small groups, vocalizations were isolated using a triangular hydrophone array and the behavioral movement patterns were captured by a theodolite and video camera positioned on a cliff overlooking the hyrophone locations. This dissertation is divided into four analysis chapters. In Chapter 3, discriminant analysis was used to validate the four N04 call subtypes which were originally parsed due to variations in slope segments. The first two functions of the discriminant analysis explained 97% of the variability. Most of the variability for the N04 call was found in the front convex and the terminal portions of the call, while very little variability was found in the center region of the call. This research revealed that individual killer whales produced multiple subtypes of the N04 call. No correlations of behaviors to acoustic parameters obtained were found. The aim of the Chapter 4 was to determine if killer whale calling behavior varied prior to and after the animals had joined. Pulsed call rates were found to be greater pre- compared to post-joining events. Two-way vocal exchanges were more common occurring 74% of the time during pre-joining events. In Chapter 5, initiated and first response to calls varied between age/sex class groups when mothers were separated from an offspring. Solo mothers and calves initiated pulsed calls more often than they responded. Most of the no vocal responses were due to mothers who were foraging. Finally, observations of the frequency split in N04

Revisiting the role of individual variability in population persistence and stability.

Directory of Open Access Journals (Sweden)

Andrew Morozov

Full Text Available Populations often exhibit a pronounced degree of individual variability and this can be important when constructing ecological models. In this paper, we revisit the role of inter-individual variability in population persistence and stability under predation pressure. As a case study, we consider interactions between a structured population of zooplankton grazers and their predators. Unlike previous structured population models, which only consider variability of individuals according to the age or body size, we focus on physiological and behavioural structuring. We first experimentally demonstrate a high degree of variation of individual consumption rates in three dominant species of herbivorous copepods (Calanus finmarchicus, Calanus glacialis, Calanus euxinus and show that this disparity implies a pronounced variation in the consumption capacities of individuals. Then we construct a parsimonious predator-prey model which takes into account the intra-population variability of prey individuals according to behavioural traits: effectively, each organism has a 'personality' of its own. Our modelling results show that structuring of prey according to their growth rate and vulnerability to predation can dampen predator-prey cycles and enhance persistence of a species, even if the resource stock for prey is unlimited. The main mechanism of efficient top-down regulation is shown to work by letting the prey population become dominated by less vulnerable individuals when predator densities are high, while the trait distribution recovers when the predator densities are low.

Intra-Gene DNA Methylation Variability Is a Clinically Independent Prognostic Marker in Women's Cancers.

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Bartlett, Thomas E; Jones, Allison; Goode, Ellen L; Fridley, Brooke L; Cunningham, Julie M; Berns, Els M J J; Wik, Elisabeth; Salvesen, Helga B; Davidson, Ben; Trope, Claes G; Lambrechts, Sandrina; Vergote, Ignace; Widschwendter, Martin

2015-01-01

We introduce a novel per-gene measure of intra-gene DNA methylation variability (IGV) based on the Illumina Infinium HumanMethylation450 platform, which is prognostic independently of well-known predictors of clinical outcome. Using IGV, we derive a robust gene-panel prognostic signature for ovarian cancer (OC, n = 221), which validates in two independent data sets from Mayo Clinic (n = 198) and TCGA (n = 358), with significance of p = 0.004 in both sets. The OC prognostic signature gene-panel is comprised of four gene groups, which represent distinct biological processes. We show the IGV measurements of these gene groups are most likely a reflection of a mixture of intra-tumour heterogeneity and transcription factor (TF) binding/activity. IGV can be used to predict clinical outcome in patients individually, providing a surrogate read-out of hard-to-measure disease processes.

Intra-Gene DNA Methylation Variability Is a Clinically Independent Prognostic Marker in Women's Cancers.

Directory of Open Access Journals (Sweden)

Thomas E Bartlett

Full Text Available We introduce a novel per-gene measure of intra-gene DNA methylation variability (IGV based on the Illumina Infinium HumanMethylation450 platform, which is prognostic independently of well-known predictors of clinical outcome. Using IGV, we derive a robust gene-panel prognostic signature for ovarian cancer (OC, n = 221, which validates in two independent data sets from Mayo Clinic (n = 198 and TCGA (n = 358, with significance of p = 0.004 in both sets. The OC prognostic signature gene-panel is comprised of four gene groups, which represent distinct biological processes. We show the IGV measurements of these gene groups are most likely a reflection of a mixture of intra-tumour heterogeneity and transcription factor (TF binding/activity. IGV can be used to predict clinical outcome in patients individually, providing a surrogate read-out of hard-to-measure disease processes.

Stimulant Treatment Reduces Lapses in Attention among Children with ADHD: The Effects of Methylphenidate on Intra-Individual Response Time Distributions

Science.gov (United States)

Spencer, Sarah V.; Hawk, Larry W., Jr.; Richards, Jerry B.; Shiels, Keri; Pelham, William E., Jr.; Waxmonsky, James G.

2009-01-01

Recent research has suggested that intra-individual variability in reaction time (RT) distributions of children with ADHD is characterized by a particularly large rightward skew that may reflect lapses in attention. The purpose of the study was to provide the first randomized, placebo-controlled test of the effects of the stimulant methylphenidate…

Intra-Gene DNA Methylation Variability Is a Clinically Independent Prognostic Marker in Women’s Cancers

Science.gov (United States)

Bartlett, Thomas E.; Jones, Allison; Goode, Ellen L.; Fridley, Brooke L.; Cunningham, Julie M.; Berns, Els M. J. J.; Wik, Elisabeth; Salvesen, Helga B.; Davidson, Ben; Trope, Claes G.; Lambrechts, Sandrina; Vergote, Ignace; Widschwendter, Martin

2015-01-01

We introduce a novel per-gene measure of intra-gene DNA methylation variability (IGV) based on the Illumina Infinium HumanMethylation450 platform, which is prognostic independently of well-known predictors of clinical outcome. Using IGV, we derive a robust gene-panel prognostic signature for ovarian cancer (OC, n = 221), which validates in two independent data sets from Mayo Clinic (n = 198) and TCGA (n = 358), with significance of p = 0.004 in both sets. The OC prognostic signature gene-panel is comprised of four gene groups, which represent distinct biological processes. We show the IGV measurements of these gene groups are most likely a reflection of a mixture of intra-tumour heterogeneity and transcription factor (TF) binding/activity. IGV can be used to predict clinical outcome in patients individually, providing a surrogate read-out of hard-to-measure disease processes. PMID:26629914

On the intra-seasonal variability within the extratropics in a general circulation model and observational data

International Nuclear Information System (INIS)

May, W.; Bengtsson, L.

1994-01-01

There are various phenomena on different spatial and temporal scales contributing to the intra-seasonal variability within the extratropics. One may notice higher-frequency baroclinic disturbances affecting the day-to-day variability of the atmosphere. But one finds also low-frequency fluctuations on a typical time scale of a few weeks. Blocking anticyclones are probably the most prominent example of such features. These fluctuations on different scales, however, are influencing each other, in particular the temporal evolution and spatial distribution. There has been observational work on various phenomena contributing to the intra-seasonal variability for a long time. In the last decade or so, however, with the increasing importance of General Circulation Models there have been some studies dealing with the intra-seasonal variability as simulated by these models

Similar or disparate brain patterns? The intra-personal EEG variability of three women with multiple personality disorder.

Science.gov (United States)

Lapointe, A R; Crayton, J W; DeVito, R; Fichtner, C G; Konopka, L M

2006-07-01

Quantitative EEG was used to assess the intra-personal variability of brain electrical activity for 3 women diagnosed with Multiple Personality Disorder (MPD). Two separate control groups (within-subject and between-subject) were used to test the hypothesis that the intra-personal EEG variability between 2 alters would be less than the interpersonal EEG variability between 2 controls, and similar to the intra-personal EEG variability of a single personality. This hypothesis was partially supported. In general, the 2 EEG records of a MPD subject (alter 1 vs. alter 2) were more different from one another than the 2 EEG records of a single control, but less different from one another than the EEG records of 2 separate controls. Most of the EEG variability between alters involved beta activity in the frontal and temporal lobes.

Focus on variability : New tools to study intra-individual variability in developmental data

NARCIS (Netherlands)

van Geert, P; van Dijk, M

2002-01-01

In accordance with dynamic systems theory, we assume that variability is an important developmental phenomenon. However, the standard methodological toolkit of the developmental psychologist offers few instruments for the study of variability. In this article we will present several new methods that

Impact of Reconstruction Algorithms on CT Radiomic Features of Pulmonary Tumors: Analysis of Intra- and Inter-Reader Variability and Inter-Reconstruction Algorithm Variability.

Science.gov (United States)

Kim, Hyungjin; Park, Chang Min; Lee, Myunghee; Park, Sang Joon; Song, Yong Sub; Lee, Jong Hyuk; Hwang, Eui Jin; Goo, Jin Mo

2016-01-01

To identify the impact of reconstruction algorithms on CT radiomic features of pulmonary tumors and to reveal and compare the intra- and inter-reader and inter-reconstruction algorithm variability of each feature. Forty-two patients (M:F = 19:23; mean age, 60.43±10.56 years) with 42 pulmonary tumors (22.56±8.51mm) underwent contrast-enhanced CT scans, which were reconstructed with filtered back projection and commercial iterative reconstruction algorithm (level 3 and 5). Two readers independently segmented the whole tumor volume. Fifteen radiomic features were extracted and compared among reconstruction algorithms. Intra- and inter-reader variability and inter-reconstruction algorithm variability were calculated using coefficients of variation (CVs) and then compared. Among the 15 features, 5 first-order tumor intensity features and 4 gray level co-occurrence matrix (GLCM)-based features showed significant differences (palgorithms. As for the variability, effective diameter, sphericity, entropy, and GLCM entropy were the most robust features (CV≤5%). Inter-reader variability was larger than intra-reader or inter-reconstruction algorithm variability in 9 features. However, for entropy, homogeneity, and 4 GLCM-based features, inter-reconstruction algorithm variability was significantly greater than inter-reader variability (palgorithms. Inter-reconstruction algorithm variability was greater than inter-reader variability for entropy, homogeneity, and GLCM-based features.

Variable Copy Number, Intra-Genomic Heterogeneities and Lateral Transfers of the 16S rRNA Gene in Pseudomonas

Science.gov (United States)

Bodilis, Josselin; Nsigue-Meilo, Sandrine; Besaury, Ludovic; Quillet, Laurent

2012-01-01

Even though the 16S rRNA gene is the most commonly used taxonomic marker in microbial ecology, its poor resolution is still not fully understood at the intra-genus level. In this work, the number of rRNA gene operons, intra-genomic heterogeneities and lateral transfers were investigated at a fine-scale resolution, throughout the Pseudomonas genus. In addition to nineteen sequenced Pseudomonas strains, we determined the 16S rRNA copy number in four other Pseudomonas strains by Southern hybridization and Pulsed-Field Gel Electrophoresis, and studied the intra-genomic heterogeneities by Denaturing Gradient Gel Electrophoresis and sequencing. Although the variable copy number (from four to seven) seems to be correlated with the evolutionary distance, some close strains in the P. fluorescens lineage showed a different number of 16S rRNA genes, whereas all the strains in the P. aeruginosa lineage displayed the same number of genes (four copies). Further study of the intra-genomic heterogeneities revealed that most of the Pseudomonas strains (15 out of 19 strains) had at least two different 16S rRNA alleles. A great difference (5 or 19 nucleotides, essentially grouped near the V1 hypervariable region) was observed only in two sequenced strains. In one of our strains studied (MFY30 strain), we found a difference of 12 nucleotides (grouped in the V3 hypervariable region) between copies of the 16S rRNA gene. Finally, occurrence of partial lateral transfers of the 16S rRNA gene was further investigated in 1803 full-length sequences of Pseudomonas available in the databases. Remarkably, we found that the two most variable regions (the V1 and V3 hypervariable regions) had probably been laterally transferred from another evolutionary distant Pseudomonas strain for at least 48.3 and 41.6% of the 16S rRNA sequences, respectively. In conclusion, we strongly recommend removing these regions of the 16S rRNA gene during the intra-genus diversity studies. PMID:22545126

Intra-Night Variability of OJ 287 with Long-Term Multiband Optical Monitoring

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Wei Zeng

2017-11-01

Full Text Available We present long-term optical multi-band photometric monitoring of the blazar OJ 287 from 6 March 2010 to 3 April 2016, with high temporal resolution in the V R I -bands. The flux variations and colour-magnitude variations on long and short timescales were investigated to understand the emission mechanisms. In our observation, the major outbursts occurred in January 2016, as predicted by the binary pair of black holes model for OJ 287, with F v a r of 1.3∼2.1%, and variability amplitude (Amp of 5.8∼9.0%. The intra-night variability (IDV durations were from 18.5 to 51.3 min, and the minimal variability timescale was about 4.7 min. The colour-magnitude variation showed a weak positive correlation on the long timescale with Pearson’s r = 0 . 450 , while a negative correlation was found on intra-night timescales. We briefly discuss the possible physical mechanisms that are most likely to be responsible for the observed flux and colour-magnitude correlation variability.

Now You’re With Me, Now You’re Not: Between-Session and Within-Session Intra-Individual Variability in Attention in Aphasia

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Sarah Villard

2015-05-01

Full Text Available Introduction: Patients with aphasia (PWA have been found to exhibit impaired performance on attention tasks relative to healthy controls, even when tasks contain only non-linguistic stimuli (e.g. Robin & Rizzo, 1989. Additionally, our previous work has shown that PWA exhibit increased day-to-day, or between-session, intra-individual variability (BS-IIV on non-linguistic attention tasks (Villard & Kiran, 2015. The current study examines BS-IIV, as well as moment-to-moment, or within-session, intra-individual variability (WS-IIV, in performance on a series of non-linguistic and linguistic attention tasks. We theorize that BS-IIV and WS-IIV may be critical metrics for understanding attention processing in PWA. Methods: Data from 17 PWA and 17 age-matched healthy controls have been analyzed; data is expected from a total of 20 in each group. Each participant completed a series of five computerized experimental tasks of incrementally increasing demands/complexity. Task 1 measured non-linguistic sustained visual attention; Task 2 added visual distractor stimuli; Task 3 added non-linguistic target auditory stimuli, requiring integration of two modalities; Task 4 added lexical decision demands; and Task 5 added lexical-semantic processing demands. This series of five tasks was administered four times, on four different non-consecutive days. We hypothesized that increased task complexity would elicit increased BS-IIV and WS-IIV in attention for PWA but not for controls. Data Analysis: In order to examine BS-IIV and WS-IIV in reaction time (RT, coefficients of variation (COVs, or the standard deviation over the mean were calculated for each participant, on each task. Specifically, a COV representing BS-IIV in RT (BS-COV was calculated for each participant, each task, using data collected across the four sessions. Similarly, a COV representing WS-IIV in RT (WS-COV was calculated for each participant, each task, using data collected within a single session

Three-dimensional Mass Measurement of Subsolid Pulmonary Nodules on Chest CT: Intra and Inter-observer Variability

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Huiting LIU

2015-05-01

Full Text Available Background and objective Subsolid pulmonary nodules tend to exhibit considerably slower growth rates than solid lesions, nevertheless, higher malignancy probability. The diagnosis of indeterminate nodules largely depends on the growth evaluation during follow-up. The growth can manifested as an increase in size or the appearance and/or subsequent increase of solid components. The mass reflect the product of volume and density and can be more sensitive in growth evaluation. However, the repeatability needs a further validation. The purpose of this study is to assess the intra and inter-observer variability of mass measurement for subsolid nodules. Methods 80 subsolid nodules in 44 patients were retrospectively enrolled. Both the volume and mass were measured by two radiologists using blind method independently. Intra-observer and inter-observer variability were analyzed and compared by Bland-Altman method intra-class correlation test and Wilcoxon test. Results Software achieved satisfied segmentation for 92.5% nodules. Of them, 35% underwent manual modification. The 95% limits of agreement for intra-observer variability were -11.5%-10.4% for mass and -8.4%-8.8% for volume. The 95% limits of agreement for inter-observer variability were -17.4%-19.3% for mass and -17.9%-19.4% for volume.The intra-class correlation foefficients between volume and mass measument was 0.95 and 0.93 (both P<0.001 and no significant differences (P=0.78, 0.09 was found for intra- and inter-observer variability. Manual modification of the segmentation caused the worse mass measurement repeatability in spite of the reader satisfaction. Conclusion The repeatability of mass measurement has no significant difference with that of volume measurement and may act as a reliable method in the follow-up of subsolid nodules.

Intra- and inter-individual variation in flight direction in a migratory butterfly co-vary with individual mobility.

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Larranaga, Nicolas; Baguette, Michel; Calvez, Olivier; Trochet, Audrey; Ducatez, Simon; Legrand, Delphine

2013-08-15

Flight direction is a major component of an animal's migratory success. However, few studies have focused on variation in flight direction both between and within individuals, which is likely to be correlated with other traits implied in migration processes. We report patterns of intra- and inter-individual variation in flight direction in the large white butterfly Pieris brassicae. The presence of inter-individual variation in flight direction for individuals tested in the same conditions suggests that this trait is inherited in P. brassicae and we propose that a rapid loss of migratory skills may exist in the absence of selection for migration. The magnitude of intra-individual variation was negatively correlated to two surrogates of the potential for migration: mobility and wing length. Highly mobile and longed-winged individuals within the same family were found to fly in similar directions, whereas less mobile and short-winged individuals displayed divergent flight direction compared with the average direction of their kin. There was also a negative correlation between the variance to the mean flight direction of a family and its average mobility, but no correlation with wing length. We discuss these issues in terms of the evolution of traits potentially implied in both migration and dispersal in P. brassicae.

Multi-Band Intra-Night Optical Variability of BL Lacertae

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Haritma Gaur

2017-12-01

Full Text Available We monitored BL Lacertae frequently during 2014–2016 when it was generally in a high state. We searched for intra-day variability for 43 nights using quasi-simultaneous measurements in the B, V, R, and I bands (totaling 143 light curves; the typical sampling interval was about eight minutes. On hour-like timescales, BL Lac exhibited significant variations during 13 nights in various optical bands. Significant spectral variations are seen during most of these nights such that the optical spectrum becomes bluer when brighter. The amplitude of variability is usually greater for longer observations but is lower when BL Lac is brighter. No evidence for periodicities or characteristic variability time-scales in the light curves was found. The color variations are mildly chromatic on long timescales.

SU-G-206-07: Dual-Energy CT Inter- and Intra-Scanner Variability Within One Make and Model

International Nuclear Information System (INIS)

Jacobsen, M; Wood, C; Cody, D

2016-01-01

Purpose: It can be logistically quite difficult to scan patients on the same exact device for their repeat visits in multi-scanner facilities. The reliability between dual-energy CT scanners’ quantitative results is not known, nor is their individual repeatability. Therefore, we evaluated inter- and intra-scanner variability with respect to several key clinical quantitative metrics specific to dual-energy CT. Methods: Eleven identical GE HD-750 CT scanners in a busy clinical environment were used to perform dual-energy (DE) CT scans of a large elliptical quality control (QC) phantom (Gammex, Inc.; Middleton, WI) which contains many standard insert materials. The DE-QC phantom was scanned bi-weekly during 2016; 3 to 4 scans were obtained from each scanner (a total of 35 data sets were used for analysis). Iodine accuracy for the 2mg/ml, 5mg/ml and 15mg/ml rods (from the Iodine(Water) image set) and soft tissue HU (40 HU based on NIST constants) from the 50keV data set were used to assess inter- and intra-scanner variability (standard deviation). Results: Intra-scanner variability average for 2mg/ml Iodine was 0.10 mg/ml (range 0.05–0.15 mg/ml), for 5mg/ml Iodine was 0.12 mg/ml (range 0.07–0.16 mg/ml), for 15 mg/ml Iodine was 0.25 mg/ml (range 0.16–0.37 mg/ml), and for the soft tissue inserts was 2.1 HU (range 1.8–2.6 HU). Inter-scanner variability average for 2mg/ml Iodine was 0.16 mg/ml (range 0.11–0.19 mg/ml), for 5mg/ml Iodine was 0.18 mg/ml (range 0.11–0.22 mg/ml), for 15 mg/ml Iodine was 0.35 mg/ml (range 0.23–0.44 mg/ml), and for the soft tissue inserts was 3.8 HU (range 3.1–4.5 HU). Conclusion: Intra-scanner variability for the iodine and soft tissue inserts averaged 3.1% and 5.2% respectively, and inter-scanner variability for these regions analyzed averaged 5.0% and 9.5%, respectively. Future work will include determination of smallest measurable change and acceptable limits for DE-CT scanner variability over longer time intervals. This

Variability of gastric emptying time using standardized radiolabeled meals

International Nuclear Information System (INIS)

Christian, P.E.; Brophy, C.M.; Egger, M.J.; Taylor, A.; Moore, J.G.

1984-01-01

To define the range of inter- and intra-subject variability on gastric emptying measurements, eight healthy male subjects (ages 19-40) received meals on four separate occasions. The meal consisted of 150 g of beef stew labeled with Tc-99m SC labeled liver (600 μCi) and 150 g of orange juice containing In-111 DTPA (100 μCi) as the solid- and liquid-phase markers respectively. Images of the solid and liquid phases were obtained at 20 min intervals immediately after meal ingestion. The stomach region was selected from digital images and data were corrected for radionuclide interference, radioactive decay and the geometric mean of anterior and posterior counts. More absolute variability was seen with the solid than the liquid marker emptying for the group. The mean solid half-emptying time was 58 +- 17 min (range 29-92) while the mean liquid half-emptying time was 24 +- 8 min (range 12-37). A nested random effects analysis of variance showed moderate intra-subject variability for solid half-emptying times (rho = 0.4594), and high intra-subject variability was implied by a low correlation (rho = 0.2084) for liquid half-emptying. The average inter-subject differences were 58.3% of the total variance for solids (rho = 0.0017). For liquids, the inter-subject variability was 69.1% of the total variance, but was only suggestive of statistical significance (rho = 0.0666). The normal half emptying time for gastric emptying of liquids and solids is a variable phenomenon in healthy subjects and has great inter- and intra-individual day-to-day differences

Variability of gastric emptying time using standardized radiolabeled meals

Energy Technology Data Exchange (ETDEWEB)

Christian, P.E.; Brophy, C.M.; Egger, M.J.; Taylor, A.; Moore, J.G.

1984-01-01

To define the range of inter- and intra-subject variability on gastric emptying measurements, eight healthy male subjects (ages 19-40) received meals on four separate occasions. The meal consisted of 150 g of beef stew labeled with Tc-99m SC labeled liver (600 ..mu..Ci) and 150 g of orange juice containing In-111 DTPA (100 ..mu..Ci) as the solid- and liquid-phase markers respectively. Images of the solid and liquid phases were obtained at 20 min intervals immediately after meal ingestion. The stomach region was selected from digital images and data were corrected for radionuclide interference, radioactive decay and the geometric mean of anterior and posterior counts. More absolute variability was seen with the solid than the liquid marker emptying for the group. The mean solid half-emptying time was 58 +- 17 min (range 29-92) while the mean liquid half-emptying time was 24 +- 8 min (range 12-37). A nested random effects analysis of variance showed moderate intra-subject variability for solid half-emptying times (rho = 0.4594), and high intra-subject variability was implied by a low correlation (rho = 0.2084) for liquid half-emptying. The average inter-subject differences were 58.3% of the total variance for solids (rho = 0.0017). For liquids, the inter-subject variability was 69.1% of the total variance, but was only suggestive of statistical significance (rho = 0.0666). The normal half emptying time for gastric emptying of liquids and solids is a variable phenomenon in healthy subjects and has great inter- and intra-individual day-to-day differences.

Individual Movement Variability Magnitudes Are Explained by Cortical Neural Variability.

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Haar, Shlomi; Donchin, Opher; Dinstein, Ilan

2017-09-13

Humans exhibit considerable motor variability even across trivial reaching movements. This variability can be separated into specific kinematic components such as extent and direction that are thought to be governed by distinct neural processes. Here, we report that individual subjects (males and females) exhibit different magnitudes of kinematic variability, which are consistent (within individual) across movements to different targets and regardless of which arm (right or left) was used to perform the movements. Simultaneous fMRI recordings revealed that the same subjects also exhibited different magnitudes of fMRI variability across movements in a variety of motor system areas. These fMRI variability magnitudes were also consistent across movements to different targets when performed with either arm. Cortical fMRI variability in the posterior-parietal cortex of individual subjects explained their movement-extent variability. This relationship was apparent only in posterior-parietal cortex and not in other motor system areas, thereby suggesting that individuals with more variable movement preparation exhibit larger kinematic variability. We therefore propose that neural and kinematic variability are reliable and interrelated individual characteristics that may predispose individual subjects to exhibit distinct motor capabilities. SIGNIFICANCE STATEMENT Neural activity and movement kinematics are remarkably variable. Although intertrial variability is rarely studied, here, we demonstrate that individual human subjects exhibit distinct magnitudes of neural and kinematic variability that are reproducible across movements to different targets and when performing these movements with either arm. Furthermore, when examining the relationship between cortical variability and movement variability, we find that cortical fMRI variability in parietal cortex of individual subjects explained their movement extent variability. This enabled us to explain why some subjects

Climate variability and Great Plains agriculture

International Nuclear Information System (INIS)

Rosenberg, N.J.; Katz, L.A.

1991-01-01

The ways in which inhabitants of the Great Plains, including Indians, early settlers, and 20th century farmers, have adapted to climate changes on the Great Plains are explored. The climate of the Great Plains, because of its variability and extremes, can be very stressful to plants, animals and people. It is suggested that agriculture and society on the Great Plains have, during the last century, become less vulnerable to the stresses imposed by climate. Opinions as to the sustainability of agriculture on the Great Plains vary substantially. Lockeretz (1981) suggests that large scale, high cost technologies have stressed farmers by creating surpluses and by requiring large investments. Opie (1989) sees irrigation as a climate substitute, however he stresses that the Ogallala aquifer must inevitably become depleted. Deborah and Frank Popper (1987) believe that farming on the Plains is unsustainable, and destruction of shelterbelts, out-migration of the rural population and environmental problems will lead to total collapse. With global warming, water in the Great Plains is expected to become scarcer, and although improvements in irrigation efficiency may slow depletion of the Ogallala aquifer, ultimately the acreage under irrigation must decrease to levels that can be sustained by natural recharge and reliable surface flows. 23 refs., 2 figs

Capturing the dynamics of response variability in the brain in ADHD

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Janna van Belle

2015-01-01

Full Text Available ADHD is characterized by increased intra-individual variability in response times during the performance of cognitive tasks. However, little is known about developmental changes in intra-individual variability, and how these changes relate to cognitive performance. Twenty subjects with ADHD aged 7–24 years and 20 age-matched, typically developing controls participated in an fMRI-scan while they performed a go-no-go task. We fit an ex-Gaussian distribution on the response distribution to objectively separate extremely slow responses, related to lapses of attention, from variability on fast responses. We assessed developmental changes in these intra-individual variability measures, and investigated their relation to no-go performance. Results show that the ex-Gaussian measures were better predictors of no-go performance than traditional measures of reaction time. Furthermore, we found between-group differences in the change in ex-Gaussian parameters with age, and their relation to task performance: subjects with ADHD showed age-related decreases in their variability on fast responses (sigma, but not in lapses of attention (tau, whereas control subjects showed a decrease in both measures of variability. For control subjects, but not subjects with ADHD, this age-related reduction in variability was predictive of task performance. This group difference was reflected in neural activation: for typically developing subjects, the age-related decrease in intra-individual variability on fast responses (sigma predicted activity in the dorsal anterior cingulate gyrus (dACG, whereas for subjects with ADHD, activity in this region was related to improved no-go performance with age, but not to intra-individual variability. These data show that using more sophisticated measures of intra-individual variability allows the capturing of the dynamics of task performance and associated neural changes not permitted by more traditional measures.

Credit spread variability in U.S. business cycles: the Great Moderation versus the Great Recession

OpenAIRE

Hylton Hollander; Guangling Liu

2014-01-01

This paper establishes the prevailing financial factors that influence credit spread variability, and its impact on the U.S. business cycle over the Great Moderation and Great Recession periods. To do so, we develop a dynamic general equilibrium framework with a central role of financial intermediation and equity assets. Over the Great Moderation and Great Recession periods, we find an important role for bank market power (sticky rate adjustments and loan rate markups) on credit spread variab...

Credit spread variability in U.S. business cycles: The Great Moderation versus the Great Recession

OpenAIRE

Hylton Hollander and Guangling Liu

2014-01-01

This paper establishes the prevailing financial factors that influence credit spread variability, and its impact on the U.S. business cycle over the Great Moderation and Great Recession periods. To do so, we develop a dynamic general equilibrium framework with a central role of financial intermediation and equity assets. Over the Great Moderation and Great Recession periods, we find an important role for bank market power (sticky rate adjustments and loan rate markups) on credit spread variab...

Neuroticism, intelligence, and intra-individual variability in elementary cognitive tasks: testing the mental noise hypothesis.

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Colom, Roberto; Quiroga, Ma Angeles

2009-08-01

Some studies show positive correlations between intraindividual variability in elementary speed measures (reflecting processing efficiency) and individual differences in neuroticism (reflecting instability in behaviour). The so-called neural noise hypothesis assumes that higher levels of noise are related both to smaller indices of processing efficiency and greater levels of neuroticism. Here, we test this hypothesis measuring mental speed by means of three elementary cognitive tasks tapping similar basic processes but varying systematically their content (verbal, numerical, and spatial). Neuroticism and intelligence are also measured. The sample comprised 196 undergraduate psychology students. The results show that (1) processing efficiency is generally unrelated to individual differences in neuroticism, (2) processing speed and efficiency correlate with intelligence, and (3) only the efficiency index is genuinely related to intelligence when the colinearity between speed and efficiency is controlled.

Corruption of the intra-gene DNA methylation architecture is a hallmark of cancer.

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Bartlett, Thomas E; Zaikin, Alexey; Olhede, Sofia C; West, James; Teschendorff, Andrew E; Widschwendter, Martin

2013-01-01

Epigenetic processes--including DNA methylation--are increasingly seen as having a fundamental role in chronic diseases like cancer. It is well known that methylation levels at particular genes or loci differ between normal and diseased tissue. Here we investigate whether the intra-gene methylation architecture is corrupted in cancer and whether the variability of levels of methylation of individual CpGs within a defined gene is able to discriminate cancerous from normal tissue, and is associated with heterogeneous tumour phenotype, as defined by gene expression. We analysed 270985 CpGs annotated to 18272 genes, in 3284 cancerous and 681 normal samples, corresponding to 14 different cancer types. In doing so, we found novel differences in intra-gene methylation pattern across phenotypes, particularly in those genes which are crucial for stem cell biology; our measures of intra-gene methylation architecture are a better determinant of phenotype than measures based on mean methylation level alone (K-S test [Formula: see text] in all 14 diseases tested). These per-gene methylation measures also represent a considerable reduction in complexity, compared to conventional per-CpG beta-values. Our findings strongly support the view that intra-gene methylation architecture has great clinical potential for the development of DNA-based cancer biomarkers.

Long-Term Variability of Satellite Lake Surface Water Temperatures in the Great Lakes

Science.gov (United States)

Gierach, M. M.; Matsumoto, K.; Holt, B.; McKinney, P. J.; Tokos, K.

2014-12-01

The Great Lakes are the largest group of freshwater lakes on Earth that approximately 37 million people depend upon for fresh drinking water, food, flood and drought mitigation, and natural resources that support industry, jobs, shipping and tourism. Recent reports have stated (e.g., the National Climate Assessment) that climate change can impact and exacerbate a range of risks to the Great Lakes, including changes in the range and distribution of certain fish species, increased invasive species and harmful algal blooms, declining beach health, and lengthened commercial navigation season. In this study, we will examine the impact of climate change on the Laurentian Great Lakes through investigation of long-term lake surface water temperatures (LSWT). We will use the ATSR Reprocessing for Climate: Lake Surface Water Temperature & Ice Cover (ARC-Lake) product over the period 1995-2012 to investigate individual and interlake variability. Specifically, we will quantify the seasonal amplitude of LSWTs, the first and last appearances of the 4°C isotherm (i.e., an important identifier of the seasonal evolution of the lakes denoting winter and summer stratification), and interpret these quantities in the context of global interannual climate variability such as ENSO.

Delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC): Intra- and Interobserver Variability in Standardized Drawing of Regions of Interest

International Nuclear Information System (INIS)

Tiderius, C.J.; Tjoernstrand, J.; Aakeson, P.; Soedersten, K.; Dahlberg, L.; Leander, P.

2004-01-01

Purpose: To establish the reproducibility of a standardized region of interest (ROI) drawing procedure in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC). Material and Methods: A large ROI in lateral and medial femoral weight-bearing cartilage was drawn in images of 12 healthy male volunteers by 6 investigators with different skills in MRI. The procedure was done twice, with a 1-week interval. Calculated T1-values were evaluated for intra- and interobserver variability. Results: The mean interobserver variability for both compartments ranged between 1.3% and 2.3% for the 6 different investigators without correlation to their experience in MRI. Post-contrast intra-observer variability was low in both the lateral and the medial femoral cartilage, 2.6% and 1.5%, respectively. The larger variability in lateral than in medial cartilage was related to slightly longer and thinner ROIs. Conclusion: Intra-observer variability and interobserver variability are both low when a large standardized ROI is used in dGEMRIC. The experience of the investigator does not affect the variability, which further supports a clinical applicability of the method

Intra-cystic concentrations of albendazole-sulphoxide in human cystic echinococcosis: a systematic review and analysis of individual patient data.

Science.gov (United States)

Lötsch, Felix; Naderer, Judith; Skuhala, Tomislava; Groger, Mirjam; Auer, Herbert; Kaczirek, Klaus; Waneck, Fredrik; Ramharter, Michael

2016-08-01

Cystic echinococcosis (CE) is a widespread zoonosis caused by the species complex Echinococcus granulosus. Albendazole (ABZ)-the first-line anthelminthic drug for medical treatment of CE-is metabolized in vivo to the active derivative ABZ-sulphoxide (ABZ-SO). Target-site ABZ-SO concentrations in the hydatid cyst mediate the anthelminthic effect in CE. Primary outcome of this systematic review of individual patient data was the intra-cystic ABZ-SO concentration stratified by cyst size, location, calcification status and use of praziquantel. Studies reporting intra-cystic ABZ-SO concentrations in humans were identified by a systematic search. A pooled analysis of individual patient data was performed to assess intra-cystic concentrations. Pharmacokinetic data of 121 individual cysts were analysed. There was no correlation between plasma and intra-cystic ABZ-SO concentrations (rho = -0.03, p = 0.76). Intra-cystic drug concentrations were also not associated with sex and treatment duration. Use of praziquantel in combination with ABZ was associated with higher plasma (median 540 vs. 240 μg/L; p = 0.04) but not intra-cystic ABZ-SO concentrations (median 220 vs. 199 μg/L; p = 0.36). Relative drug concentrations in hepatic cysts were higher than in other cysts (0.8 vs. 0.4; p = 0.05). Intra-cystic concentrations were higher in calcified than non-calcified cysts (median 897 vs. 245 μg/L; p = 0.03). There was a trend towards higher intra-cystic concentrations in smaller sized cysts (β = -17.2 μg/L/cm; 95th CI, -35.9 to 1.6; p = 0.07). This study demonstrates that mean intra-cystic drug concentrations are similar to plasma concentrations on a population level. However, in individual patients plasma concentrations are not directly predictive for intra-cystic concentrations. The use of booster drugs was not associated with higher intra-cystic ABZ-SO concentrations in this analysis.

The Leech method for diagnosing constipation: intra- and interobserver variability and accuracy

International Nuclear Information System (INIS)

Lorijn, Fleur de; Voskuijl, Wieger P.; Taminiau, Jan A.; Benninga, Marc A.; Rijn, Rick R. van; Henneman, Onno D.F.; Heijmans, Jarom; Reitsma, Johannes B.

2006-01-01

The data concerning the value of a plain abdominal radiograph in childhood constipation are inconsistent. Recently, positive results have been reported of a new radiographic scoring system, ''the Leech method'', for assessing faecal loading. To assess intra- and interobserver variability and determine diagnostic accuracy of the Leech method in identifying children with functional constipation (FC). A total of 89 children (median age 9.8 years) with functional gastrointestinal disorders were included in the study. Based on clinical parameters, 52 fulfilled the criteria for FC, six fulfilled the criteria for functional abdominal pain (FAP), and 31 for functional non-retentive faecal incontinence (FNRFI); the latter two groups provided the controls. To assess intra- and interobserver variability of the Leech method three scorers scored the same abdominal radiograph twice. A Leech score of 9 or more was considered as suggestive of constipation. ROC analysis was used to determine the diagnostic accuracy of the Leech method in separating patients with FC from control patients. Significant intraobserver variability was found between two scorers (P=0.005 and P<0.0001), whereas there was no systematic difference between the two scores of the other scorer (P=0.89). The scores between scorers differed systematically and displayed large variability. The area under the ROC curve was 0.68 (95% CI 0.58-0.80), indicating poor diagnostic accuracy. The Leech scoring method for assessing faecal loading on a plain abdominal radiograph is of limited value in the diagnosis of FC in children. (orig.)

Intra-operative mapping of the atria: the first step towards individualization of atrial fibrillation therapy?

Science.gov (United States)

Kik, Charles; Mouws, Elisabeth M J P; Bogers, Ad J J C; de Groot, Natasja M S

2017-07-01

Atrial fibrillation (AF), an age-related progressive disease, is becoming a worldwide epidemic with a prevalence rate of 33 million. Areas covered: In this expert review, an overview of important results obtained from previous intra-operative mapping studies is provided. In addition, our novel intra-operative high resolution mapping studies, its surgical considerations and data analyses are discussed. Furthermore, the importance of high resolution mapping studies of both sinus rhythm and AF for the development of future AF therapy is underlined by our most recent results. Expert commentary: Progression of AF is determined by the extensiveness of electropathology which is defined as conduction disorders caused by structural damage of atrial tissue. The severity of electropathology is a major determinant of therapy failure. At present, we do not have any diagnostic tool to determine the degree of electropathology in the individual patient and we can thus not select the most optimal treatment modality for the individual patient. An intra-operative, high resolution scale, epicardial mapping approach combined with quantification of electrical parameters may serve as a diagnostic tool to stage AF in the individual patient and to provide patient tailored therapy.

Intra-Personal and Extra-Personal Predictors of Suicide Attempts of South Korean Adolescents

Science.gov (United States)

Lee, Ji-Young; Bae, Sung-Man

2015-01-01

The purpose of this study was to explore significant variables predicting adolescent suicidal attempts. Socio-environmental variables such as gender, school record, school grade, school adaptation, and family intimacy together with intra-individual variables including depression, anxiety, delinquency, stress, and self-esteem were considered as…

Writer Identification and Verification from Intra-variable Individual Handwriting

OpenAIRE

Adak, Chandranath; Chaudhuri, Bidyut B.; Blumenstein, Michael

2017-01-01

The handwriting of an individual may vary excessively with many factors such as mood, time, space, writing speed, writing medium, utensils etc. Therefore, it becomes more challenging to perform automated writer verification/ identification on a particular set of handwritten patterns (e.g. speedy handwriting) of a person, especially when the system is trained using a different set of writing patterns (e.g. normal/medium speed) of that same person. However, it would be interesting to experiment...

The Leech method for diagnosing constipation: intra- and interobserver variability and accuracy

Energy Technology Data Exchange (ETDEWEB)

Lorijn, Fleur de; Voskuijl, Wieger P.; Taminiau, Jan A.; Benninga, Marc A. [Emma Children' s Hospital, Department of Paediatric Gastroenterology and Nutrition, Amsterdam (Netherlands); Rijn, Rick R. van; Henneman, Onno D.F. [Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Heijmans, Jarom [Emma Children' s Hospital, Department of Paediatric Gastroenterology and Nutrition, Amsterdam (Netherlands); Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Reitsma, Johannes B. [Academic Medical Centre, Department of Clinical Epidemiology and Biostatistics, Amsterdam (Netherlands)

2006-01-01

The data concerning the value of a plain abdominal radiograph in childhood constipation are inconsistent. Recently, positive results have been reported of a new radiographic scoring system, ''the Leech method'', for assessing faecal loading. To assess intra- and interobserver variability and determine diagnostic accuracy of the Leech method in identifying children with functional constipation (FC). A total of 89 children (median age 9.8 years) with functional gastrointestinal disorders were included in the study. Based on clinical parameters, 52 fulfilled the criteria for FC, six fulfilled the criteria for functional abdominal pain (FAP), and 31 for functional non-retentive faecal incontinence (FNRFI); the latter two groups provided the controls. To assess intra- and interobserver variability of the Leech method three scorers scored the same abdominal radiograph twice. A Leech score of 9 or more was considered as suggestive of constipation. ROC analysis was used to determine the diagnostic accuracy of the Leech method in separating patients with FC from control patients. Significant intraobserver variability was found between two scorers (P=0.005 and P<0.0001), whereas there was no systematic difference between the two scores of the other scorer (P=0.89). The scores between scorers differed systematically and displayed large variability. The area under the ROC curve was 0.68 (95% CI 0.58-0.80), indicating poor diagnostic accuracy. The Leech scoring method for assessing faecal loading on a plain abdominal radiograph is of limited value in the diagnosis of FC in children. (orig.)

Inter- and intra-strain variability of tandem repeats in Mycoplasma pneumoniae based on next-generation sequencing data.

Science.gov (United States)

Zhang, Jing; Song, Xiaohong; Ma, Marella J; Xiao, Li; Kenri, Tsuyoshi; Sun, Hongmei; Ptacek, Travis; Li, Shaoli; Waites, Ken B; Atkinson, T Prescott; Shibayama, Keigo; Dybvig, Kevin; Feng, Yanmei

2017-02-01

To characterize inter- and intra-strain variability of variable-number tandem repeats (VNTRs) in Mycoplasma pneumoniae to determine the optimal multilocus VNTR analysis scheme for improved strain typing. Whole genome assemblies and next-generation sequencing data from diverse M. pneumoniae isolates were used to characterize VNTRs and their variability, and to compare the strain discriminability of new VNTR and existing markers. We identified 13 VNTRs including five reported previously. These VNTRs displayed different levels of inter- and intra-strain copy number variations. All new markers showed similar or higher discriminability compared with existing VNTR markers and the P1 typing system. Our study provides novel insights into VNTR variations and potential new multilocus VNTR analysis schemes for improved genotyping of M. pneumoniae.

Inter- and intra-specific variability in δ13C and δ18O values of freshwater gastropod shells from Lake Lednica, western Poland

Science.gov (United States)

Apolinarska, Karina; Pełechaty, Mariusz

2017-09-01

This study focuses on the inter- and intra-specific variability in δ13C and δ18O values of shells and opercula of gastropods sampled live from the littoral zone of Lake Lednica, western Poland. The δ13C and δ18O values were measured in individual opercula of Bithynia tentaculata and in shells of Bithynia tentaculata, Gyraulus albus, Gyraulus crista, Lymnaea sp., Physa fontinalis, Radix auricularia, Theodoxus fluviatilis and Valvata cristata. The gastropods selected for the study are among the species most commonly found in European Quaternary lacustrine sediments. The carbon isotope composition of the gastropod shells was species-specific and the same order of species from the most to the least 13C-depleted was observed at all sites sampled. Differences in shell δ13C values between species were similar at all sampling sites, thus the factors influencing shell isotopic composition were interpreted as species-specific. The δ18O values of shells were similar in all the species investigated. Significant intra-specific variability in shell δ13C and δ18O values was observed not only within the populations of Lake Lednica, which can be explained by heterogeneity of δ13C DIC, δ18O water and water temperature between the sites where macrophytes with snails attached were sampled, but also between individuals sampled from restricted areas of the lake's bottom. The latter points to the importance of factors related to the ontogeny of individual gastropods.

Intra-session and inter-session variability of nitric oxide pulmonary diffusing capacity in adults with cystic fibrosis.

Science.gov (United States)

Radtke, Thomas; Benden, Christian; Maggi-Beba, Marion; Kriemler, Susi; van der Lee, Ivo; Dressel, Holger

2017-12-01

We evaluated the intra-session and inter-session variability of the diffusing capacity of nitric oxide (DLNO), carbon monoxide (DLCO), alveolar-capillary membrane diffusing capacity for carbon monoxide (DMCO) and pulmonary capillary blood volume (Vc) in patients with cystic fibrosis (CF). Patients performed single-breath diffusing capacity measurements during all of 3 consecutive study visits. Precision of gas diffusing parameters was quantified by within-subject standard deviation (SD ws ) and coefficient of variation (CV). Intra-session and inter-session reproducibility was determined by SD ws *2.77. 15 clinically stable patients were included. The intra-session precision of gas diffusing parameters improved over the study visits. The inter-session SD ws for DLNO, DLCO, DMCO, and Vc was 4.8, 1.3, 2.4, and 4.3, respectively. Reproducibility was 13.3, 3.8, 6.7 and 12.0mLmin -1 mmHg -1 ; CV was 4.4, 4.7, 4.4 and 5.8%, respectively. The intra-session variability of DLNO, DLCO, DMCO and Vc improves with breath-hold maneuver training in test-naïve patients with CF, indicating a learning effect. Inter-session reproducibility data are lower than those previously reported in healthy subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

Intra- and Inter-Individual Differences in Adolescent Depressive Mood: the Role of Relationships with Parents and Friends.

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Zhang, Shiyu; Baams, Laura; van de Bongardt, Daphne; Dubas, Judith Semon

2018-05-01

Utilizing four waves of data from 1126 secondary school Dutch adolescents (Mage = 13.95 at the first wave; 53% boys), the current study examined the interplay between parent-adolescent and friend-adolescent relationship quality (satisfaction and conflict) in relation to adolescents' depressive mood. Using multilevel analyses, the interacting effects of parent/friend relationship quality on depressive mood were tested at both the intra- and inter-individual level. Analyses at the intra-individual level investigated whether individual depressive mood fluctuated along with changes in their social relationships regardless of one's general level of depressive mood; and analyses at the inter-individual level examined whether the average differences in depressive mood between adolescents were associated with different qualities of social relationships. We interpreted the patterns of interactions between parent and friend relationships using four theoretical models: the reinforcement, toxic friends, compensation, and additive model. The results demonstrate the covariation of parent- and friend- relationship quality with adolescents' depressive mood, and highlight that parent and peer effects are not independent from each other-affirming the compensation and additive models at the intra-individual and the reinforcement and additive models at the inter-individual level. The findings highlight the robustness of the protective effects of parent and peer support and the deleterious effects of conflictual relationships for adolescent mental health. The results have implications for both the theoretical and practical design of (preventive) interventions aimed at decreasing adolescents' depressive mood.

Inter- and intra-annual chemical variability during the ice-free season in lakes with different flushing rates and acid deposition histories.

Science.gov (United States)

Arnott, Shelley E; Dillon, Peter J; Somers, Keith; Keller, Bill

2003-01-01

Quantifying chemical variability in different lake types is important for the assessment of both chemical and biological responses to environmental change. For monitoring programs that emphasize a large number of lakes at the expense of frequent samples, high variability may influence how representative single samples are of the average conditions of individual lakes. Intensive temporal data from long-term research sites provide a unique opportunity to assess chemical variability in lakes with different characteristics. We compared the intra- and inter-annual variability of four acidification related variables (Gran alkalinity, pH, sulphate concentration, and total base cation concentration) in four lakes with different flushing rates and acid deposition histories. Variability was highest in lakes with high flushing rates and was not influenced by historic acid deposition in our study lakes. This has implications for the amount of effort required in monitoring programs. Lakes with high flushing rates will require more frequent sampling intervals than lakes with low flushing rates. Consideration of specific lake types should be included in the design of monitoring programs.

Intra-night optical variability properties of X-ray bright Narrow-line Seyfert 1 galaxies

Science.gov (United States)

Ojha, Vineet; Chand, Hum; Gopal-Krishna

2018-04-01

We present Intra Night Optical Variability (INOV) study of the 9 Narrow-line Seyfert 1 (NLSy 1) galaxies which are detected in X-ray at more than 3σ level. Our observations cover a total of 9 nights ( 36 hr) with each NLSy 1 monitored for ≥ 3.5 hr in each night. After applying F-test to assess variability status of these sources, we found none of these sources to be variable. Such non-variability nature of X-ray detected NLSy 1 galaxies suggests the lack of jet dominance as far as X-ray emission is concerned. Higher photometric accuracy for these faint sources, achievable with the newly installed ARIES 3.6m DOT will be helpful.

Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

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Fabian Horst

Full Text Available Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours.Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins. For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns.Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales.Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the

Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

Science.gov (United States)

Horst, Fabian; Eekhoff, Alexander; Newell, Karl M; Schöllhorn, Wolfgang I

2017-01-01

Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours). Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins). For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns. Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales. Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the context of

Magnetic resonance imaging for prostate bed radiotherapy planning: An inter- and intra-observer variability study

International Nuclear Information System (INIS)

Barkati, Maroie; Simard, Dany; Taussky, Daniel; Delouya, Guiula

2016-01-01

We assessed the inter- and intra-observer variability in contouring the prostate bed for radiation therapy planning using MRI compared with computed tomography (CT). We selected 15 patients with prior radical prostatectomy. All had CT and MRI simulation for planning purposes. Image fusions were done between CT and MRI. Three radiation oncologists with several years of experience in treating prostate cancer contoured the prostate bed first on CT and then on MRI. Before contouring, each radiation oncologist had to review the Radiation Therapy Oncology Group guidelines for postoperative external beam radiotherapy. The agreement between volumes was calculated using the Dice similarity coefficient (DSC). Analysis was done using the Matlab software. The DSC was compared using non-parametric statistical tests. Contouring on CT alone showed a statistically significant (P = 0.001) higher similarity between observers with a mean DSC of 0.76 (standard deviation ± 0.05) compared with contouring on MRI with a mean of 0.66 (standard deviation ± 0.05). Mean intra-observer variability between CT and MRI was 0.68, 0.75 and 0.78 for the three observers. The clinical target volume was 19 - 74% larger on CT than on MRI. The intra-observer difference in clinical target volume between CT and MRI was statistically significant in two observers and non-significant in the third one (P = 0.09). We found less inter-observer variability when contouring on CT than on MRI. Radiation Therapy Oncology Group contouring guidelines are based on anatomical landmarks readily visible on CT. These landmarks are more inter-observer dependent on MRI. Therefore, present contouring guidelines might not be applicable to MRI planning.

Root biomass production in populations of six rooted macrophytes in response to Cu exposure: intra-specific variability versus constitutive-like tolerance.

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Marchand, L; Nsanganwimana, F; Lamy, J B; Quintela-Sabaris, C; Gonnelli, C; Colzi, I; Fletcher, T; Oustrière, N; Kolbas, A; Kidd, P; Bordas, F; Newell, P; Alvarenga, P; Deletic, A; Mench, M

2014-10-01

Intra-specific variability of root biomass production (RP) of six rooted macrophytes, i.e. Juncus effusus, Phragmites australis, Schoenoplectus lacustris, Typha latifolia, Phalaris arundinacea, and Iris pseudacorus grown from clones, in response to Cu exposure was investigated. Root biomass production varied widely for all these macrophytes in control conditions (0.08 μM) according to the sampling site. Root biomass production of T. latifolia and I. pseudacorus in the 2.5-25 μM Cu range depended on the sampling location but not on the Cu dose in the growth medium. For P. australis, J. effusus, S. lacustris, and P. arundinacea, an intra-specific variability of RP depending on both the sampling location and the Cu-dose was evidenced. This intra-specific variability of RP depending on the sampling location and of Cu-tolerance for these last four species suggests that Cu constitutive tolerance for all rooted macrophytes is not a species-wide trait but it exhibits variability for some species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Consistently Showing Your Best Side? Intra-individual Consistency in #Selfie Pose Orientation

Science.gov (United States)

Lindell, Annukka K.

2017-01-01

Painted and photographic portraits of others show an asymmetric bias: people favor their left cheek. Both experimental and database studies confirm that the left cheek bias extends to selfies. To date all such selfie studies have been cross-sectional; whether individual selfie-takers tend to consistently favor the same pose orientation, or switch between multiple poses, remains to be determined. The present study thus examined intra-individual consistency in selfie pose orientations. Two hundred selfie-taking participants (100 male and 100 female) were identified by searching #selfie on Instagram. The most recent 10 single-subject selfies for the each of the participants were selected and coded for type of selfie (normal; mirror) and pose orientation (left, midline, right), resulting in a sample of 2000 selfies. Results indicated that selfie-takers do tend to consistently adopt a preferred pose orientation (α = 0.72), with more participants showing an overall left cheek bias (41%) than would be expected by chance (overall right cheek bias = 31.5%; overall midline bias = 19.5%; no overall bias = 8%). Logistic regression modellng, controlling for the repeated measure of participant identity, indicated that sex did not affect pose orientation. However, selfie type proved a significant predictor when comparing left and right cheek poses, with a stronger left cheek bias for mirror than normal selfies. Overall, these novel findings indicate that selfie-takers show intra-individual consistency in pose orientation, and in addition, replicate the previously reported left cheek bias for selfies and other types of portrait, confirming that the left cheek bias also presents within individuals’ selfie corpora. PMID:28270790

The Great Cross-Border Bank Deleveraging; Supply Constraints and Intra-Group Frictions

OpenAIRE

Eugenio M Cerutti; Stijn Claessens

2014-01-01

International banks greatly reduced their direct cross-border and local affiliates’ lending as the global financial crisis strained balance sheets, lowered borrower demand, and changed government policies. Using bilateral, lender-borrower countrydata and controlling for credit demand, we show that reductions largely varied in line with markets’ prior assessments of banks’ vulnerabilities, with banks’ financial statement variables and lender-borrower country characteristics playing minor roles...

Tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species

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Isabelle Laforest-Lapointe

2016-08-01

Full Text Available Background The diversity and composition of the microbial community of tree leaves (the phyllosphere varies among trees and host species and along spatial, temporal, and environmental gradients. Phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. Sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly selected leaves from throughout the canopy. In this context, our goal was to characterize the relative importance of intra-individual variation in phyllosphere communities across multiple species, and compare this variation to inter-individual and interspecific variation of phyllosphere epiphytic bacterial communities in a natural temperate forest in Quebec, Canada. Methods We targeted five dominant temperate forest tree species including angiosperms and gymnosperms: Acer saccharum, Acer rubrum, Betula papyrifera, Abies balsamea and Picea glauca. For one randomly selected tree of each species, we sampled microbial communities at six distinct canopy locations: bottom-canopy (1–2 m height, the four cardinal points of mid-canopy (2–4 m height, and the top-canopy (4–6 m height. We also collected bottom-canopy leaves from five additional trees from each species. Results Based on an analysis of bacterial community structure measured via Illumina sequencing of the bacterial 16S gene, we demonstrate that 65% of the intra-individual variation in leaf bacterial community structure could be attributed to the effect of inter-individual and inter-specific differences while the effect of canopy location was not significant. In comparison, host species identity explains 47% of inter-individual and inter-specific variation in leaf bacterial community structure followed by individual identity (32% and canopy location (6%. Discussion Our results suggest that

Intra-basin variability of snowmelt water balance calculations in a subarctic catchment

Science.gov (United States)

McCartney, Stephen E.; Carey, Sean K.; Pomeroy, John W.

2006-03-01

The intra-basin variability of snowmelt and melt-water runoff hydrology in an 8 km2 subarctic alpine tundra catchment was examined for the 2003 melt period. The catchment, Granger Creek, is within the Wolf Creek Research Basin, Yukon, which is typical of mountain subarctic landscapes in northwestern Canada. The study catchment was segmented into nine internally uniform zones termed hydrological response units (HRUs) based on their similar hydrological, physiographic, vegetation and soil properties. Snow accumulation exhibited significant variability among the HRUs, with greatest snow water equivalent in areas of tall shrub vegetation. Melt began first on southerly exposures and at lower elevations, yet average melt rates for the study period varied little among HRUs with the exception of those with steep aspects. In HRUs with capping organic soils, melt water first infiltrated this surface horizon, satisfying its storage capacity, and then percolated into the frozen mineral substrate. Infiltration and percolation into frozen mineral soils was restricted where melt occurred rapidly and organic soils were thin; in this case, melt-water delivery rates exceeded the frozen mineral soil infiltration rate, resulting in high runoff rates. In contrast, where there were slower melt rates and thick organic soils, infiltration was unlimited and runoff was suppressed. The snow water equivalent had a large impact on runoff volume, as soil storage capacity was quickly surpassed in areas of deep snow, diverting the bulk of melt water laterally to the drainage network. A spatially distributed water balance indicated that the snowmelt freshet was primarily controlled by areas with tall shrub vegetation that accumulate large quantities of snow and by alpine areas with no capping organic soils. The intra-basin water balance variability has important implications for modelling freshet in hydrological models.

Intra-individual metameric variation expressed at the enamel-dentine junction of lower post-canine dentition of South African fossil hominins and modern humans.

Science.gov (United States)

Pan, Lei; Thackeray, John Francis; Dumoncel, Jean; Zanolli, Clément; Oettlé, Anna; de Beer, Frikkie; Hoffman, Jakobus; Duployer, Benjamin; Tenailleau, Christophe; Braga, José

2017-08-01

The aim of this study is to compare the degree and patterning of inter- and intra-individual metameric variation in South African australopiths, early Homo and modern humans. Metameric variation likely reflects developmental and taxonomical issues, and could also be used to infer ecological and functional adaptations. However, its patterning along the early hominin postcanine dentition, particularly among South African fossil hominins, remains unexplored. Using microfocus X-ray computed tomography (µXCT) and geometric morphometric tools, we studied the enamel-dentine junction (EDJ) morphology and we investigated the intra- and inter-individual EDJ metameric variation among eight australopiths and two early Homo specimens from South Africa, as well as 32 modern humans. Along post-canine dentition, shape changes between metameres represented by relative positions and height of dentine horns, outlines of the EDJ occlusal table are reported in modern and fossil taxa. Comparisons of EDJ mean shapes and multivariate analyses reveal substantial variation in the direction and magnitude of metameric shape changes among taxa, but some common trends can be found. In modern humans, both the direction and magnitude of metameric shape change show increased variability in M 2 -M 3 compared to M 1 -M 2 . Fossil specimens are clustered together showing similar magnitudes of shape change. Along M 2 -M 3 , the lengths of their metameric vectors are not as variable as those of modern humans, but they display considerable variability in the direction of shape change. The distalward increase of metameric variation along the modern human molar row is consistent with the odontogenetic models of molar row structure (inhibitory cascade model). Though much remains to be tested, the variable trends and magnitudes in metamerism in fossil hominins reported here, together with differences in the scale of shape change between modern humans and fossil hominins may provide valuable information

The Area of Secondary Hyperalgesia following Heat Stimulation in Healthy Male Volunteers: Inter- and Intra-Individual Variance and Reproducibility.

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Morten Sejer Hansen

Full Text Available Clinical pain models can be applied when investigating basic physiologic pain responses in healthy volunteers. Several pain models exist; however, only few have been adequately validated. Our primary aim with this prospective study was to investigate the intra- and inter-individual variation in secondary hyperalgesia elicited by brief thermal sensitization (45°C for 3 min in healthy volunteers.Fifty healthy volunteers were included. Areas of secondary hyperalgesia following brief thermal sensitization were investigated by 2 observers on 4 experimental days, with a minimum interval of 7 days. Additionally, heat pain detection threshold and pain during thermal stimulation (45°C for 1 min., and the psychological tests Pain Catastrophizing Scale and Hospital Anxiety and Depression Score were applied.For areas of secondary hyperalgesia, an intra-observer intra-person correlation of 0.85, 95% CI [0.78, 0.90], an intra-observer inter-person correlation of 0.03, 95% CI [0.00, 0.16], and a coefficient of variation of 0.17, 95% CI [0.14, 0.21] was demonstrated. Four percent of the study population had areas of secondary hyperalgesia both below the 1st and above the 3rd quartile considering all included participants. Heat pain detection threshold predicted area of secondary hyperalgesia with an adjusted R2 of 0.20 (P = 0.0006.We have demonstrated a low intra-individual, and a high inter-individual variation in thermally induced secondary hyperalgesia. We conclude that brief thermal sensitization produce secondary hyperalgesia with a high level of reproducibility, which can be applied to investigate different phenotypes related to secondary hyperalgesia in healthy volunteers.clinicaltrials.gov NCT02166164.

Atomoxetine could improve intra-individual variability in drug-naïve adults with attention-deficit/hyperactivity disorder comparably with methylphenidate: A head-to-head randomized clinical trial.

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Ni, Hsing-Chang; Hwang Gu, Shoou-Lian; Lin, Hsiang-Yuan; Lin, Yu-Ju; Yang, Li-Kuang; Huang, Hui-Chun; Gau, Susan Shur-Fen

2016-05-01

Intra-individual variability in reaction time (IIV-RT) is common in individuals with attention-deficit/hyperactivity disorder (ADHD). It can be improved by stimulants. However, the effects of atomoxetine on IIV-RT are inconclusive. We aimed to investigate the effects of atomoxetine on IIV-RT, and directly compared its efficacy with methylphenidate in adults with ADHD. An 8-10 week, open-label, head-to-head, randomized clinical trial was conducted in 52 drug-naïve adults with ADHD, who were randomly assigned to two treatment groups: immediate-release methylphenidate (n=26) thrice daily (10-20 mg per dose) and atomoxetine once daily (n=26) (0.5-1.2 mg/kg/day). IIV-RT, derived from the Conners' continuous performance test (CCPT), was represented by the Gaussian (reaction time standard error, RTSE) and ex-Gaussian models (sigma and tau). Other neuropsychological functions, including response errors and mean of reaction time, were also measured. Participants received CCPT assessments at baseline and week 8-10 (60.4±6.3 days). We found comparable improvements in performances of CCPT between the immediate-release methylphenidate- and atomoxetine-treated groups. Both medications significantly improved IIV-RT in terms of reducing tau values with comparable efficacy. In addition, both medications significantly improved inhibitory control by reducing commission errors. Our results provide evidence to support that atomoxetine could improve IIV-RT and inhibitory control, of comparable efficacy with immediate-release methylphenidate, in drug-naïve adults with ADHD. Shared and unique mechanisms underpinning these medication effects on IIV-RT awaits further investigation. © The Author(s) 2016.

Landscape heterogeneity drives intra-population niche variation and reproduction in an arctic top predator.

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L'hérault, Vincent; Franke, Alastair; Lecomte, Nicolas; Alogut, Adam; Bêty, Joël

2013-09-01

While intra-population variability in resource use is ubiquitous, little is known of how this measure of niche diversity varies in space and its role in population dynamics. Here we examined how heterogeneous breeding environments can structure intra-population niche variation in both resource use and reproductive output. We investigated intra-population niche variation in the Arctic tundra ecosystem, studying peregrine falcon (Falco peregrinus tundrius, White) breeding within a terrestrial-marine gradient near Rankin Inlet, Nunavut, Canada. Using stable isotope analysis, we found that intra-population niches varied at the individual level; we examined within-nest and among-nest variation, though only the latter varied along the terrestrial-marine gradient (i.e., increased among-nest variability among birds nesting within the marine environment, indicating higher degree of specialization). Terrestrial prey species (small herbivores and insectivores) were consumed by virtually all falcons. Falcons nesting within the marine environment made use of marine prey (sea birds), but depended heavily on terrestrial prey (up to 90% of the diet). Using 28-years of peregrine falcon nesting data, we found a positive relationship between the proportion of terrestrial habitat surrounding nest sites and annual nestling production, but no relationship with the likelihood of successfully rearing at least one nestling reaching 25 days old. Annually, successful inland breeders raised 0.47 more young on average compared to offshore breeders, which yields potential fitness consequences for this long-living species. The analyses of niche and reproductive success suggest a potential breeding cost for accessing distant terrestrial prey, perhaps due to additional traveling costs, for those individuals with marine nest site locations. Our study indicates how landscape heterogeneity can generate proximate (niche variation) and ultimate (reproduction) consequences on a population of generalist

Response variability of different anodal transcranial direct current stimulation intensities across multiple sessions.

Science.gov (United States)

Ammann, Claudia; Lindquist, Martin A; Celnik, Pablo A

It is well known that transcranial direct current stimulation (tDCS) is capable of modulating corticomotor excitability. However, a source of growing concern has been the observed inter- and intra-individual variability of tDCS-responses. Recent studies have assessed whether individuals respond in a predictable manner across repeated sessions of anodal tDCS (atDCS). The findings of these investigations have been inconsistent, and their methods have some limitations (i.e. lack of sham condition or testing only one tDCS intensity). To study inter- and intra-individual variability of atDCS effects at two different intensities on primary motor cortex (M1) excitability. Twelve subjects participated in a crossover study testing 7-min atDCS over M1 in three separate conditions (2 mA, 1 mA, sham) each repeated three times separated by 48 h. Motor evoked potentials were recorded before and after stimulation (up to 30min). Time of testing was maintained consistent within participants. To estimate the reliability of tDCS effects across sessions, we calculated the Intra-class Correlation Coefficient (ICC). AtDCS at 2 mA, but not 1 mA, significantly increased cortical excitability at the group level in all sessions. The overall ICC revealed fair to high reliability of tDCS effects for multiple sessions. Given that the distribution of responses showed important variability in the sham condition, we established a Sham Variability-Based Threshold to classify responses and to track individual changes across sessions. Using this threshold an intra-individual consistent response pattern was then observed only for the 2 mA condition. 2 mA anodal tDCS results in consistent intra- and inter-individual increases of M1 excitability. Copyright © 2017 Elsevier Inc. All rights reserved.

Success of intra-arterial chemotherapy (chemosurgery) for retinoblastoma: effect of orbitovascular anatomy.

Science.gov (United States)

Marr, Brian P; Hung, Crystal; Gobin, Yves P; Dunkel, Ira J; Brodie, Scott E; Abramson, David H

2012-02-01

To review results of orbital angiography performed during intra-arterial chemotherapy (chemosurgery) for treatment of retinoblastoma to assess the association of angiographic variability in orbitovascular anatomy with tumor response and outcomes. Medical records and 64 orbital angiograms were reviewed for 56 pediatric patients with retinoblastoma undergoing chemosurgery using a combination of melphalan hydrochloride, topotecan hydrochloride, or carboplatin. The major orbital arteries and capillary blush patterns were graded, and tumor response and recurrence were compared using the log-rank and Fisher exact tests. Statistically significant variables for tumor response were lacrimal artery prominence (P = .001), previous treatment (P = .003), and lacrimal blush (P = .004). The only statistically significant variable for vitreous seed response was ciliary body blush (P = .03). Statistically significant variables influencing time to recurrence and time to enucleation were choroidal blush absence (P = .01) and lacrimal artery presence (P = .03), respectively. The success of intra-arterial chemotherapy is dependent on delivery of drug to the target tumor within the eye via the ophthalmic artery. Because of the small volume of drug used (0.50-1.25 mL per treatment) and the selectivity of catheterization, variables affecting orbital blood flow greatly influence drug delivery and the success of chemosurgery.

Quantification and variability in colonic volume with a novel magnetic resonance imaging method

DEFF Research Database (Denmark)

Nilsson, M; Sandberg, Thomas Holm; Poulsen, Jakob Lykke

2015-01-01

Background: Segmental distribution of colorectal volume is relevant in a number of diseases, but clinical and experimental use demands robust reliability and validity. Using a novel semi-automatic magnetic resonance imaging-based technique, the aims of this study were to describe: (i) inter......-individual and intra-individual variability of segmental colorectal volumes between two observations in healthy subjects and (ii) the change in segmental colorectal volume distribution before and after defecation. Methods: The inter-individual and intra-individual variability of four colorectal volumes (cecum...... (p = 0.02). Conclusions & Inferences: Imaging of segmental colorectal volume, morphology, and fecal accumulation is advantageous to conventional methods in its low variability, high spatial resolution, and its absence of contrast-enhancing agents and irradiation. Hence, the method is suitable...

Intra-hemispheric intrinsic connectivity asymmetry and its relationships with handedness and language Lateralization.

Science.gov (United States)

Joliot, M; Tzourio-Mazoyer, N; Mazoyer, B

2016-12-01

Asymmetry in intra-hemispheric intrinsic connectivity, and its association with handedness and hemispheric dominance for language, were investigated in a sample of 290 healthy volunteers enriched in left-handers (52.7%). From the resting-state FMRI data of each participant, we derived an intra-hemispheric intrinsic connectivity asymmetry (HICA) matrix as the difference between the left and right intra-hemispheric matrices of intrinsic correlation computed for each pair of the AICHA atlas ROIs. We defined a similarity measure between the HICA matrices of two individuals as the correlation coefficient of their corresponding elements, and computed for each individual an index of intra-hemispheric intrinsic connectivity asymmetry as the average similarity measure of his HICA matrix to those of the other subjects of the sample (HICAs). Gaussian-mixture modeling of the age-corrected HICAs sample distribution revealed that two types of HICA patterns were present, one (Typical_HICA) including 92.4% of the participants while the other (Atypical_HICA) included only 7.6% of them, mostly left-handers. In addition, we investigated the relationship between asymmetry in intra-hemispheric intrinsic connectivity and language hemispheric dominance, including a potential effect of handedness on this relationship, thanks to an FMRI acquisition during language production from which an hemispheric functional lateralization index for language (HFLI) and a type of hemispheric dominance for language, namely leftward, ambilateral, or rightward, were derived for each individual. There was a significant association between the types of language hemispheric dominance and of intra-hemispheric intrinsic connectivity asymmetry, occurrence of Atypical_HICAs individuals being very high in the group of individuals rightward-lateralized for language (80%), reduced in the ambilateral group (19%) and rare in individuals leftward-lateralized for language (less than 3%). Quantitatively, we found a

Effects of visual feedback-induced variability on motor learning of handrim wheelchair propulsion.

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Leving, Marika T; Vegter, Riemer J K; Hartog, Johanneke; Lamoth, Claudine J C; de Groot, Sonja; van der Woude, Lucas H V

2015-01-01

It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are thought to be closely related during the learning process. 17 Participants received visual feedback-based practice (feedback group) and 15 participants received regular practice (natural learning group). Both groups received equal practice dose of 80 min, over 3 weeks, at 0.24 W/kg at a treadmill speed of 1.11 m/s. To compare both groups the pre- and post-test were performed without feedback. The feedback group received real-time visual feedback on seven propulsion variables with instruction to manipulate the presented variable to achieve the highest possible variability (1st 4-min block) and optimize it in the prescribed direction (2nd 4-min block). To increase motor exploration the participants were unaware of the exact variable they received feedback on. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated to evaluate the amount of intra-individual variability. The feedback group, which practiced with higher intra-individual variability, improved the propulsion technique between pre- and post-test to the same extent as the natural learning group. Mechanical efficiency improved between pre- and post-test in the natural learning group but remained unchanged in the feedback group. These results suggest that feedback-induced variability inhibited the improvement in mechanical efficiency. Moreover, since both groups improved propulsion technique but only the natural learning group improved mechanical efficiency, it can be concluded that the improvement in mechanical efficiency and propulsion technique do not always appear

Effects of visual feedback-induced variability on motor learning of handrim wheelchair propulsion.

Directory of Open Access Journals (Sweden)

Marika T Leving

Full Text Available It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are thought to be closely related during the learning process.17 Participants received visual feedback-based practice (feedback group and 15 participants received regular practice (natural learning group. Both groups received equal practice dose of 80 min, over 3 weeks, at 0.24 W/kg at a treadmill speed of 1.11 m/s. To compare both groups the pre- and post-test were performed without feedback. The feedback group received real-time visual feedback on seven propulsion variables with instruction to manipulate the presented variable to achieve the highest possible variability (1st 4-min block and optimize it in the prescribed direction (2nd 4-min block. To increase motor exploration the participants were unaware of the exact variable they received feedback on. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated to evaluate the amount of intra-individual variability.The feedback group, which practiced with higher intra-individual variability, improved the propulsion technique between pre- and post-test to the same extent as the natural learning group. Mechanical efficiency improved between pre- and post-test in the natural learning group but remained unchanged in the feedback group.These results suggest that feedback-induced variability inhibited the improvement in mechanical efficiency. Moreover, since both groups improved propulsion technique but only the natural learning group improved mechanical efficiency, it can be concluded that the improvement in mechanical efficiency and propulsion technique do not

Narrow intra-individual variation of maternal thyroid function in pregnancy based on a longitudinal study on 132 women

DEFF Research Database (Denmark)

Boas, M.; Forman, Julie Lyng; Juul, A.

2009-01-01

BACKGROUND: Adaptive alterations in maternal physiology cause changes in thyroid hormone levels throughout pregnancy, and precise biochemical evaluation is thus highly dependent on gestation-specific reference intervals and expected intra-individual variation. OBJECTIVE: The aim of the study...... was the assessment of the intra-individual variation as well as the longitudinal course of thyroid hormones during normal pregnancy and factors that influence the normal reference range for thyroid function. For this purpose, a longitudinal statistical model was applied. DESIGN: In a cohort of 132 pregnant women......, serial blood samples were obtained and ultrasound scans were performed throughout pregnancy. METHODS: Serum levels of TSH, free and total thyroxine (T(4)), free and total triiodothyronine (T(3)) as well as autoantibodies against thyroid peroxidase and thyroglobulin were measured in 979 serum samples...

Bioaccumulation of photoprotective compounds in copepods: environmental triggers and sources of intra-specific variability

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Zagarese, H. E.; García, P.; Diéguez, M. D.; Ferraro, M. A.

2012-12-01

Ultraviolet radiation (UVR) and temperature are two globally important abiotic factors affecting freshwater ecosystems. Planktonic organisms have developed a battery of counteracting mechanisms to minimize the risk of being damaged by UVR, which respond to three basic principles: avoid, protect, repair. Copepods are among the most successful zooplankton groups. They are highly adaptable animals, capable of displaying flexible behaviors, physiologies, and life strategies. In particular, they are well equipped to cope with harmful UVR. Their arsenal includes vertical migration, accumulation of photoprotective compounds, and photorepair. The preference for a particular strategy is affected by a plethora of environmental (extrinsic) parameters, such as the existence of a depth refuge, the risk of visual predation, and temperature. Temperature modifies the environment (e.g. the lake thermal structure), and animal metabolism (e.g., swimming speed, bioaccumulation of photoprotective compounds). In addition, the relative weight of UVR-coping strategies is also influenced by the organism (intrinsic) characteristics (e.g., inter- and intra-specific variability). The UV absorbing compounds, mycosporine-like amino acids (MAAs), are widely distributed among freshwater copepods. Animals are unable to synthesize MAAs, and therefore depend on external sources for accumulating these compounds. Although copepods may acquire MAAs from their food, for the few centropagic species investigated so far, the main source of MAAs are microbial (most likely prokaryotic) organisms living in close association with the copepods. Boeckella gracilipes is a common centropagic copepod in Patagonian lakes. We suspected that its occurrence in different types of lakes, hydrologically unconnected, but within close geographical proximity, could have resulted in different microbial-copepod associations (i.e., different MAAs sources) that could translate into intra-specific differences in the accumulation

Intra- and interobserver variability of MRI-based volume measurements of the hippocampus and amygdala using the manual ray-tracing method

International Nuclear Information System (INIS)

Achten, E.; Deblaere, K.; Damme, F. van; Kunnen, M.; Wagter, C. de; Boon, P.; Reuck, J. de

1998-01-01

We studied the intra- and interobserver variability of volume measurments of the hippocampus (HC) and the amygdala as applied to the detection of HC atrophy in patients with complex partial seizures (CPE), measuring the volumes of the HC and amygdala of 11 normal volunteers and 12 patients with presumed CPE, using the manual ray-tracing method. Two independent observers performed these measurements twice each using home-made software. The intra- and interobserver variability of the absolute volumes and of the normalised left-to-right volume differences (δV) between the HC (δV HC ), the amygdala (δV A ) and the sum of both (δV HCA) were assessed. In our mainly right-handed normals, the right HC and amygdala were on average 0.05 and 0.03 ml larger respectively than on the left. The interobserver variability for volume measurements in normal subjects was 1.80 ml for the HC and 0.82 ml for the amygdala, the intraobserver variability roughly one third of these values. The interobserver variability coefficient in normals was 3.6 % for δV HCA , 4.7 % for δV HC and 7.3 % for δV A . The intraobserver variability coefficient was 3.4 % for δV HCA , 4.2 % for δV HC amd 5.6 % for δV A . The variability in patients was the same for volume differences less than 5 % either side of the interval for normality, but was higher when large volume differences were encountered, is probably due to the lack of thresholding and/or normalisation. Cutoff values for lateralisation with the δV were defined. No intra- or interobserver lateralisation differences were encountered with δV HCA and δV HC . From these observations we conclude that the manual ray-tracing method is a robust method for lateralisation in patients with TLE. Due to its higher variability, this method is less suited to measure absolute volumes. (orig.) (orig.)

Intra- and interobserver variability of MRI-based volume measurements of the hippocampus and amygdala using the manual ray-tracing method

Energy Technology Data Exchange (ETDEWEB)

Achten, E.; Deblaere, K.; Damme, F. van; Kunnen, M. [MR Department 1K12, University Hospital Gent (Belgium); Wagter, C. de [Department of Radiotherapy and Nuclear Medicine, University Hospital Gent (Belgium); Boon, P.; Reuck, J. de [Department of Neurology, University Hospital Gent (Belgium)

1998-09-01

We studied the intra- and interobserver variability of volume measurments of the hippocampus (HC) and the amygdala as applied to the detection of HC atrophy in patients with complex partial seizures (CPE), measuring the volumes of the HC and amygdala of 11 normal volunteers and 12 patients with presumed CPE, using the manual ray-tracing method. Two independent observers performed these measurements twice each using home-made software. The intra- and interobserver variability of the absolute volumes and of the normalised left-to-right volume differences ({delta}V) between the HC ({delta}V{sub HC}), the amygdala ({delta}V{sub A}) and the sum of both ({delta}V{sub HCA)} were assessed. In our mainly right-handed normals, the right HC and amygdala were on average 0.05 and 0.03 ml larger respectively than on the left. The interobserver variability for volume measurements in normal subjects was 1.80 ml for the HC and 0.82 ml for the amygdala, the intraobserver variability roughly one third of these values. The interobserver variability coefficient in normals was 3.6 % for {delta}V{sub HCA}, 4.7 % for {delta}V{sub HC} and 7.3 % for {delta}V{sub A}. The intraobserver variability coefficient was 3.4 % for {delta}V{sub HCA}, 4.2 % for {delta}V{sub HC} amd 5.6 % for {delta}V{sub A}. The variability in patients was the same for volume differences less than 5 % either side of the interval for normality, but was higher when large volume differences were encountered, is probably due to the lack of thresholding and/or normalisation. Cutoff values for lateralisation with the {delta}V were defined. No intra- or interobserver lateralisation differences were encountered with {delta}V{sub HCA} and {delta}V{sub HC}. From these observations we conclude that the manual ray-tracing method is a robust method for lateralisation in patients with TLE. Due to its higher variability, this method is less suited to measure absolute volumes. (orig.) (orig.) With 2 figs., 7 tabs., 23 refs.

Spontaneous variability of pre-dialysis concentrations of uremic toxins over time in stable hemodialysis patients.

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Sunny Eloot

Full Text Available Numerous outcome studies and interventional trials in hemodialysis (HD patients are based on uremic toxin concentrations determined at one single or a limited number of time points. The reliability of these studies however entirely depends on how representative these cross-sectional concentrations are. We therefore investigated the variability of predialysis concentrations of uremic toxins over time.Prospectively collected predialysis serum samples of the midweek session of week 0, 1, 2, 3, 4, 8, 12, and 16 were analyzed for a panel of uremic toxins in stable chronic HD patients (N = 18 while maintaining dialyzer type and dialysis mode during the study period.Concentrations of the analyzed uremic toxins varied substantially between individuals, but also within stable HD patients (intra-patient variability. For urea, creatinine, beta-2-microglobulin, and some protein-bound uremic toxins, Intra-class Correlation Coefficient (ICC was higher than 0.7. However, for phosphorus, uric acid, symmetric and asymmetric dimethylarginine, and the protein-bound toxins hippuric acid and indoxyl sulfate, ICC values were below 0.7, implying a concentration variability within the individual patient even exceeding 65% of the observed inter-patient variability.Intra-patient variability may affect the interpretation of the association between a single concentration of certain uremic toxins and outcomes. When performing future outcome and interventional studies with uremic toxins other than described here, one should quantify their intra-patient variability and take into account that for solutes with a large intra-patient variability associations could be missed.

Mechanisms driving recruitment variability in fish: comparisons between the Laurentian Great Lakes and marine systems

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Pritt, Jeremy J.; Roseman, Edward F.; O'Brien, Timothy P.

2014-01-01

In his seminal work, Hjort (in Fluctuations in the great fisheries of Northern Europe. Conseil Parmanent International Pour L'Exploration De La Mar. Rapports et Proces-Verbaux, 20: 1–228, 1914) observed that fish population levels fluctuated widely, year-class strength was set early in life, and egg production by adults could not alone explain variability in year-class strength. These observations laid the foundation for hypotheses on mechanisms driving recruitment variability in marine systems. More recently, researchers have sought to explain year-class strength of important fish in the Laurentian Great Lakes and some of the hypotheses developed for marine fisheries have been transferred to Great Lakes fish. We conducted a literature review to determine the applicability of marine recruitment hypotheses to Great Lakes fish. We found that temperature, interspecific interactions, and spawner effects (abundance, age, and condition of adults) were the most important factors in explaining recruitment variability in Great Lakes fish, whereas relatively fewer studies identified bottom-up trophodynamic factors or hydrodynamic factors as important. Next, we compared recruitment between Great Lakes and Baltic Sea fish populations and found no statistical difference in factors driving recruitment between the two systems, indicating that recruitment hypotheses may often be transferable between Great Lakes and marine systems. Many recruitment hypotheses developed for marine fish have yet to be applied to Great Lakes fish. We suggest that future research on recruitment in the Great Lakes should focus on forecasting the effects of climate change and invasive species. Further, because the Great Lakes are smaller and more enclosed than marine systems, and have abundant fishery-independent data, they are excellent candidates for future hypothesis testing on recruitment in fish.

Novel mutation in TSPAN12 leads to autosomal recessive inheritance of congenital vitreoretinal disease with intra-familial phenotypic variability.

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Gal, Moran; Levanon, Erez Y; Hujeirat, Yasir; Khayat, Morad; Pe'er, Jacob; Shalev, Stavit

2014-12-01

Developmental malformations of the vitreoretinal vasculature are a heterogeneous group of conditions with various modes of inheritance, and include familial exudative vitreoretinopathy (FEVR), persistent fetal vasculature (PFV), and Norrie disease. We investigated a large consanguineous kindred with multiple affected individuals exhibiting variable phenotypes of abnormal vitreoretinal vasculature, consistent with the three above-mentioned conditions and compatible with autosomal recessive inheritance. Exome sequencing identified a novel c.542G > T (p.C181F) apparently mutation in the TSPAN12 gene that segregated with the ocular disease in the family. The TSPAN12 gene was previously reported to cause dominant and recessive FEVR, but has not yet been associated with other vitreoretinal manifestations. The intra-familial clinical variability caused by a single mutation in the TSPAN12 gene underscores the complicated phenotype-genotype correlation of mutations in this gene, and suggests that there are additional genetic and environmental factors involved in the complex process of ocular vascularization during embryonic development. Our study supports considering PFV, FEVR, and Norrie disease a spectrum of disorders, with clinical and genetic overlap, caused by mutations in distinct genes acting in the Norrin/β-catenin signaling pathway. © 2014 Wiley Periodicals, Inc.

Exploring intra- and inter-reader variability in uni-dimensional, bi-dimensional, and volumetric measurements of solid tumors on CT scans reconstructed at different slice intervals

International Nuclear Information System (INIS)

Zhao, Binsheng; Tan, Yongqiang; Bell, Daniel J.; Marley, Sarah E.; Guo, Pingzhen; Mann, Helen; Scott, Marietta L.J.; Schwartz, Lawrence H.; Ghiorghiu, Dana C.

2013-01-01

Objective: Understanding magnitudes of variability when measuring tumor size may be valuable in improving detection of tumor change and thus evaluating tumor response to therapy in clinical trials and care. Our study explored intra- and inter-reader variability of tumor uni-dimensional (1D), bi-dimensional (2D), and volumetric (VOL) measurements using manual and computer-aided methods (CAM) on CT scans reconstructed at different slice intervals. Materials and methods: Raw CT data from 30 patients enrolled in oncology clinical trials was reconstructed at 5, 2.5, and 1.25 mm slice intervals. 118 lesions in the lungs, liver, and lymph nodes were analyzed. For each lesion, two independent radiologists manually and, separately, using computer software, measured the maximum diameter (1D), maximum perpendicular diameter, and volume (CAM only). One of them blindly repeated the measurements. Intra- and inter-reader variability for the manual method and CAM were analyzed using linear mixed-effects models and Bland–Altman method. Results: For the three slice intervals, the maximum coefficients of variation for manual intra-/inter-reader variability were 6.9%/9.0% (1D) and 12.3%/18.0% (2D), and for CAM were 5.4%/9.3% (1D), 11.3%/18.8% (2D) and 9.3%/18.0% (VOL). Maximal 95% reference ranges for the percentage difference in intra-reader measurements for manual 1D and 2D, and CAM VOL were (−15.5%, 25.8%), (−27.1%, 51.6%), and (−22.3%, 33.6%), respectively. Conclusions: Variability in measuring the diameter and volume of solid tumors, manually and by CAM, is affected by CT slice interval. The 2.5 mm slice interval provides the least measurement variability. Among the three techniques, 2D has the greatest measurement variability compared to 1D and 3D

Measurement of transplanted pancreatic volume using computed tomography: reliability by intra- and inter-observer variability

International Nuclear Information System (INIS)

Lundqvist, Eva; Segelsjoe, Monica; Magnusson, Anders; Andersson, Anna; Biglarnia, Ali-Reza

2012-01-01

Background Unlike other solid organ transplants, pancreas allografts can undergo a substantial decrease in baseline volume after transplantation. This phenomenon has not been well characterized, as there are insufficient data on reliable and reproducible volume assessments. We hypothesized that characterization of pancreatic volume by means of computed tomography (CT) could be a useful method for clinical follow-up in pancreas transplant patients. Purpose To evaluate the feasibility and reliability of pancreatic volume assessment using CT scan in transplanted patients. Material and Methods CT examinations were performed on 21 consecutive patients undergoing pancreas transplantation. Volume measurements were carried out by two observers tracing the pancreatic contours in all slices. The observers performed the measurements twice for each patient. Differences in volume measurement were used to evaluate intra- and inter-observer variability. Results The intra-observer variability for the pancreatic volume measurements of Observers 1 and 2 was found to be in almost perfect agreement, with an intraclass correlation coefficient (ICC) of 0.90 (0.77-0.96) and 0.99 (0.98-1.0), respectively. Regarding inter-observer validity, the ICCs for the first and second measurements were 0.90 (range, 0.77-0.96) and 0.95 (range, 0.85-0.98), respectively. Conclusion CT volumetry is a reliable and reproducible method for measurement of transplanted pancreatic volume

Measurement of transplanted pancreatic volume using computed tomography: reliability by intra- and inter-observer variability

Energy Technology Data Exchange (ETDEWEB)

Lundqvist, Eva; Segelsjoe, Monica; Magnusson, Anders [Uppsala Univ., Dept. of Radiology, Oncology and Radiation Science, Section of Radiology, Uppsala (Sweden)], E-mail: eva.lundqvist.8954@student.uu.se; Andersson, Anna; Biglarnia, Ali-Reza [Dept. of Surgical Sciences, Section of Transplantation Surgery, Uppsala Univ. Hospital, Uppsala (Sweden)

2012-11-15

Background Unlike other solid organ transplants, pancreas allografts can undergo a substantial decrease in baseline volume after transplantation. This phenomenon has not been well characterized, as there are insufficient data on reliable and reproducible volume assessments. We hypothesized that characterization of pancreatic volume by means of computed tomography (CT) could be a useful method for clinical follow-up in pancreas transplant patients. Purpose To evaluate the feasibility and reliability of pancreatic volume assessment using CT scan in transplanted patients. Material and Methods CT examinations were performed on 21 consecutive patients undergoing pancreas transplantation. Volume measurements were carried out by two observers tracing the pancreatic contours in all slices. The observers performed the measurements twice for each patient. Differences in volume measurement were used to evaluate intra- and inter-observer variability. Results The intra-observer variability for the pancreatic volume measurements of Observers 1 and 2 was found to be in almost perfect agreement, with an intraclass correlation coefficient (ICC) of 0.90 (0.77-0.96) and 0.99 (0.98-1.0), respectively. Regarding inter-observer validity, the ICCs for the first and second measurements were 0.90 (range, 0.77-0.96) and 0.95 (range, 0.85-0.98), respectively. Conclusion CT volumetry is a reliable and reproducible method for measurement of transplanted pancreatic volume.

Variability in individual activity bursts improves ant foraging success.

Science.gov (United States)

Campos, Daniel; Bartumeus, Frederic; Méndez, Vicenç; Andrade, José S; Espadaler, Xavier

2016-12-01

Using experimental and computational methods, we study the role of behavioural variability in activity bursts (or temporal activity patterns) for individual and collective regulation of foraging in A. senilis ants. First, foraging experiments were carried out under special conditions (low densities of ants and food and absence of external cues or stimuli) where individual-based strategies are most prevalent. By using marked individuals and recording all foraging trajectories, we were then able to precisely quantify behavioural variability among individuals. Our main conclusions are that (i) variability of ant trajectories (turning angles, speed, etc.) is low compared with variability of temporal activity profiles, and (ii) this variability seems to be driven by plasticity of individual behaviour through time, rather than the presence of fixed behavioural stereotypes or specialists within the group. The statistical measures obtained from these experimental foraging patterns are then used to build a general agent-based model (ABM) which includes the most relevant properties of ant foraging under natural conditions, including recruitment through pheromone communication. Using the ABM, we are able to provide computational evidence that the characteristics of individual variability observed in our experiments can provide a functional advantage (in terms of foraging success) to the group; thus, we propose the biological basis underpinning our observations. Altogether, our study reveals the potential utility of experiments under simplified (laboratory) conditions for understanding information-gathering in biological systems. © 2016 The Author(s).

Inter-Labeler and Intra-Labeler Variability of Condition Severity Classification Models Using Active and Passive Learning Methods

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Nissim, Nir; Shahar, Yuval; Boland, Mary Regina; Tatonetti, Nicholas P; Elovici, Yuval; Hripcsak, George; Moskovitch, Robert

2018-01-01

t-test, the difference between the intra-labeler AUC standard deviation when using the consensus label, versus that value when using the other two labeling strategies, was significant only when using the passive learning method (p = 0.014), but not when using any of the three AL methods. Conclusions The use of AL methods, (a) reduces intra-labeler variability in the performance of the induced models during the training phase, and thus reduces the risk of halting the process at a local minimum that is significantly different in performance from the rest of the learned models; and (b) reduces Inter-labeler performance variance, and thus reduces the dependence on the use of a particular labeler. In addition, the use of a consensus label, agreed upon by a rather uneven group of labelers, might be at least as good as using the gold standard labeler, who might not be available, and certainly better than randomly selecting one of the group’s individual labelers. Finally, using the AL methods when provided by the consensus label reduced the intra-labeler AUC variance during the learning phase, compared to using passive learning. PMID:28456512

Inter-labeler and intra-labeler variability of condition severity classification models using active and passive learning methods.

Science.gov (United States)

Nissim, Nir; Shahar, Yuval; Elovici, Yuval; Hripcsak, George; Moskovitch, Robert

2017-09-01

standard deviation when using the consensus label, versus that value when using the other two labeling strategies, was significant only when using the passive learning method (p=0.014), but not when using any of the three AL methods. The use of AL methods, (a) reduces intra-labeler variability in the performance of the induced models during the training phase, and thus reduces the risk of halting the process at a local minimum that is significantly different in performance from the rest of the learned models; and (b) reduces Inter-labeler performance variance, and thus reduces the dependence on the use of a particular labeler. In addition, the use of a consensus label, agreed upon by a rather uneven group of labelers, might be at least as good as using the gold standard labeler, who might not be available, and certainly better than randomly selecting one of the group's individual labelers. Finally, using the AL methods: when provided by the consensus label reduced the intra-labeler AUC variance during the learning phase, compared to using passive learning. Copyright © 2017 Elsevier B.V. All rights reserved.

Inter- and intra-population genetic variability of introduced silkworm (Bombyx mori L. strains raised in Bulgaria

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Teodora Staykova

2013-01-01

Full Text Available The genetic variability of four populations belonging to two introduced silkworm strains (Bombyx mori L. of various origins has been studied using isoenzymic analysis of six enzyme systems. Nonspecific esterases, phosphoglucomutase, malate dehydrogenase, acid phosphatase, alkaline phosphatase and hexokinase from different tissue of larvae 5th instar have been analysed using PAGE. Polymorphism in six from a total of nine loci has been found. Inter- and intra-population differences have been ascertained expressed in different allele composition of the gene pool and different frequencies of alleles. A higher degree of inter-population variability has been reported on the acid phosphatase and a lower one – on the phosphoglucomutase.

Inter- and intra-population genetic variability of introduced silkworm (Bombyx mori L.) strains raised in Bulgaria

OpenAIRE

Teodora Staykova

2013-01-01

The genetic variability of four populations belonging to two introduced silkworm strains (Bombyx mori L.) of various origins has been studied using isoenzymic analysis of six enzyme systems. Nonspecific esterases, phosphoglucomutase, malate dehydrogenase, acid phosphatase, alkaline phosphatase and hexokinase from different tissue of larvae 5th instar have been analysed using PAGE. Polymorphism in six from a total of nine loci has been found. Inter- and intra-population differences have been a...

Intra-individual variability in day-to-day and month-to-month measurements of physical activity and sedentary behaviour at work and in leisure-time among Danish adults.

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Pedersen, E S L; Danquah, I H; Petersen, C B; Tolstrup, J S

2016-12-03

Accelerometers can obtain precise measurements of movements during the day. However, the individual activity pattern varies from day-to-day and there is limited evidence on measurement days needed to obtain sufficient reliability. The aim of this study was to examine variability in accelerometer derived data on sedentary behaviour and physical activity at work and in leisure-time during week days among Danish office employees. We included control participants (n = 135) from the Take a Stand! Intervention; a cluster randomized controlled trial conducted in 19 offices. Sitting time and physical activity were measured using an ActiGraph GT3X+ fixed on the thigh and data were processed using Acti4 software. Variability was examined for sitting time, standing time, steps and time spent in moderate-to-vigorous physical activity (MVPA) per day by multilevel mixed linear regression modelling. Results of this study showed that the number of days needed to obtain a reliability of 80% when measuring sitting time was 4.7 days for work and 5.5 days for leisure time. For physical activity at work, 4.0 days and 4.2 days were required to measure steps and MVPA, respectively. During leisure time, more monitoring time was needed to reliably estimate physical activity (6.8 days for steps and 5.8 days for MVPA). The number of measurement days needed to reliably estimate activity patterns was greater for leisure time than for work time. The domain specific variability is of great importance to researchers and health promotion workers planning to use objective measures of sedentary behaviour and physical activity. Clinical trials NCT01996176 .

Macrogeographical variability in the great call of Hylobates agilis: assessing the applicability of vocal analysis in studies of fine-scale taxonomy of gibbons

DEFF Research Database (Denmark)

Heller, R; Pedersen, Adam Frederik Sander; Wang, Christian William

2010-01-01

Vocal characteristics have been used extensively to distinguish different taxonomic units of gibbons (family Hylobatidae). The agile gibbon (Hylobates agilis) has a disjunct distribution range in the Southeast Asian archipelago (remnants of the former Sunda landmass), and populations on different...... islands are currently recognized as distinct subspecies or even species. We recorded great calls from female agile gibbons from two populations on Sumatra and two populations on Borneo and examined the vocal variability on four levels: within-individuals, between-individuals, between...

Effects of a common transcranial direct current stimulation (tDCS) protocol on motor evoked potentials found to be highly variable within individuals over 9 testing sessions.

Science.gov (United States)

Horvath, Jared Cooney; Vogrin, Simon J; Carter, Olivia; Cook, Mark J; Forte, Jason D

2016-09-01

Transcranial direct current stimulation (tDCS) uses a weak electric current to modulate neuronal activity. A neurophysiologic outcome measure to demonstrate reliable tDCS modulation at the group level is transcranial magnetic stimulation engendered motor evoked potentials (MEPs). Here, we conduct a study testing the reliability of individual MEP response patterns following a common tDCS protocol. Fourteen participants (7m/7f) each underwent nine randomized sessions of 1 mA, 10 min tDCS (3 anode; 3 cathode; 3 sham) delivered using an M1/orbito-frontal electrode montage (sessions separated by an average of ~5.5 days). Fifteen MEPs were obtained prior to, immediately following and in 5 min intervals for 30 min following tDCS. TMS was delivered at 130 % resting motor threshold using neuronavigation to ensure consistent coil localization. A number of non-experimental variables were collected during each session. At the individual level, considerable variability was seen among different testing sessions. No participant demonstrated an excitatory response ≥20 % to all three anodal sessions, and no participant demonstrated an inhibitory response ≥20 % to all three cathodal sessions. Intra-class correlation revealed poor anodal and cathodal test-retest reliability [anode: ICC(2,1) = 0.062; cathode: ICC(2,1) = 0.055] and moderate sham test-retest reliability [ICC(2,1) = 0.433]. Results also revealed no significant effect of tDCS at the group level. Using this common protocol, we found the effects of tDCS on MEP amplitudes to be highly variable at the individual level. In addition, no significant effects of tDCS on MEP amplitude were found at the group level. Future studies should consider utilizing a more strict experimental protocol to potentially account for intra-individual response variations.

Assessing variability in chemical acute toxicity of unionid mussels: Influence of intra- and inter-laboratory testing, life stage, and species

Science.gov (United States)

The authors developed a toxicity database for unionid mussels to examine the extent of intra- and interlaboratory variability in acute toxicity tests with mussel larvae (glochidia) and juveniles; the extent of differential sensitivity of the 2 life stages; and the variation in se...

Intra- and inter-individual variations of blood and urinary water-soluble vitamins in Japanese young adults consuming a semi-purified diet for 7 days.

Science.gov (United States)

Shibata, Katsumi; Fukuwatari, Tsutomu; Watanabe, Toshiaki; Nishimuta, Mamoru

2009-12-01

We have previously reported the levels of water-soluble vitamins in the blood and urine of Japanese young adults. In the present paper, to assess the variations in these water-soluble vitamin markers during the above experiment, we comprehensively determined the intra- and inter-individual variations of blood and urinary water-soluble vitamins to exactly the same amount of water-soluble vitamin intakes in the same experiment. The blood samples before breakfast and the 24-h urine samples were periodically collected from Japanese college male (n=10) and female (n=10) students consuming a semi-purified diet with water-soluble vitamins based on Japanese Dietary Reference Intakes for 7 d, and the intra- and inter-individual variations of blood and urinary water-soluble vitamins or their metabolites in blood and urine samples after adaptation were calculated. Although urinary excretion of vitamin B(12) and vitamin C showed high intra-individual variations in both males and females, other urinary vitamins and all blood vitamins showed less than 20% of within-subject coefficients of variance in either male or female. Those showing more than 20% of between-subject coefficients of variances in both male and female were blood vitamin B(6), vitamin B(12) and folate levels, and urinary vitamin B(1), vitamin B(2), vitamin B(12), nicotinamide metabolites, pantothenic acid, biotin and vitamin C. These results showed that oral administration of constant of water-soluble vitamins generally decreased intra-individual variation, while individual differences in urinary vitamin excretion were observed.

Spatial Topography of Individual-Specific Cortical Networks Predicts Human Cognition, Personality, and Emotion.

Science.gov (United States)

Kong, Ru; Li, Jingwei; Orban, Csaba; Sabuncu, Mert R; Liu, Hesheng; Schaefer, Alexander; Sun, Nanbo; Zuo, Xi-Nian; Holmes, Avram J; Eickhoff, Simon B; Yeo, B T Thomas

2018-06-06

Resting-state functional magnetic resonance imaging (rs-fMRI) offers the opportunity to delineate individual-specific brain networks. A major question is whether individual-specific network topography (i.e., location and spatial arrangement) is behaviorally relevant. Here, we propose a multi-session hierarchical Bayesian model (MS-HBM) for estimating individual-specific cortical networks and investigate whether individual-specific network topography can predict human behavior. The multiple layers of the MS-HBM explicitly differentiate intra-subject (within-subject) from inter-subject (between-subject) network variability. By ignoring intra-subject variability, previous network mappings might confuse intra-subject variability for inter-subject differences. Compared with other approaches, MS-HBM parcellations generalized better to new rs-fMRI and task-fMRI data from the same subjects. More specifically, MS-HBM parcellations estimated from a single rs-fMRI session (10 min) showed comparable generalizability as parcellations estimated by 2 state-of-the-art methods using 5 sessions (50 min). We also showed that behavioral phenotypes across cognition, personality, and emotion could be predicted by individual-specific network topography with modest accuracy, comparable to previous reports predicting phenotypes based on connectivity strength. Network topography estimated by MS-HBM was more effective for behavioral prediction than network size, as well as network topography estimated by other parcellation approaches. Thus, similar to connectivity strength, individual-specific network topography might also serve as a fingerprint of human behavior.

Wider-community Segregation and the Effect of Neighbourhood Ethnic Diversity on Social Capital: An Investigation into Intra-Neighbourhood Trust in Great Britain and London.

Science.gov (United States)

Laurence, James

2017-10-01

Extensive research has demonstrated that neighbourhood ethnic diversity is negatively associated with intra-neighbourhood social capital. This study explores the role of segregation and integration in this relationship. To do so it applies three-level hierarchical linear models to two sets of data from across Great Britain and within London, and examines how segregation across the wider-community in which a neighbourhood is nested impacts trust amongst neighbours. This study replicates the increasingly ubiquitous finding that neighbourhood diversity is negatively associated with neighbour-trust. However, we demonstrate that this relationship is highly dependent on the level of segregation across the wider-community in which a neighbourhood is nested. Increasing neighbourhood diversity only negatively impacts neighbour-trust when nested in more segregated wider-communities. Individuals living in diverse neighbourhoods nested within integrated wider-communities experience no trust-penalty. These findings show that segregation plays a critical role in the neighbourhood diversity/trust relationship, and that its absence from the literature biases our understanding of how ethnic diversity affects social cohesion.

Individualized exergame training improves postural control in advanced degenerative spinocerebellar ataxia: A rater-blinded, intra-individually controlled trial.

Science.gov (United States)

Schatton, Cornelia; Synofzik, Matthis; Fleszar, Zofia; Giese, Martin A; Schöls, Ludger; Ilg, Winfried

2017-06-01

Treatment options are rare in degenerative ataxias, especially in advanced, multisystemic disease. Exergame training might offer a novel treatment strategy, but its effectiveness has not been investigated in advanced stages. We examined the effectiveness of a 12-week home-based training with body-controlled videogames in 10 young subjects with advanced degenerative ataxia unable or barely able to stand. Training was structured in two 6-weeks phases, allowing to adapt the training according to individual training progress. Rater-blinded clinical assessment (Scale for the Assessment and Rating of Ataxia; SARA), individual goal-attainment scoring (GAS), and quantitative movement analysis were performed two weeks before training, immediately prior to training, and after training phases 1 and 2 (intra-individual control design). This study is registered with ClinicalTrials.gov, NCT02874911). After intervention, ataxia symptoms were reduced (SARA -2.5 points, p training (p = 0.04). Goal attainment during daily living was higher than expected (GAS: 0.45). Movement analysis revealed reduced body sway while sitting (p training-induced improvements in posture control mechanisms. This study provides first evidence that, even in advanced stages, subjects with degenerative ataxia may benefit from individualized training, with effects translating into daily living and improving underlying control mechanisms. The proposed training strategy can be performed at home, is motivating and facilitates patient self-empowerment. Copyright © 2017 Elsevier Ltd. All rights reserved.

In situ study of the impact of inter- and intra-reader variability on region of interest (ROI) analysis in preclinical molecular imaging.

Science.gov (United States)

Habte, Frezghi; Budhiraja, Shradha; Keren, Shay; Doyle, Timothy C; Levin, Craig S; Paik, David S

2013-01-01

We estimated reader-dependent variability of region of interest (ROI) analysis and evaluated its impact on preclinical quantitative molecular imaging. To estimate reader variability, we used five independent image datasets acquired each using microPET and multispectral fluorescence imaging (MSFI). We also selected ten experienced researchers who utilize molecular imaging in the same environment that they typically perform their own studies. Nine investigators blinded to the data type completed the ROI analysis by drawing ROIs manually that delineate the tumor regions to the best of their knowledge and repeated the measurements three times, non-consecutively. Extracted mean intensities of voxels within each ROI are used to compute the coefficient of variation (CV) and characterize the inter- and intra-reader variability. The impact of variability was assessed through random samples iterated from normal distributions for control and experimental groups on hypothesis testing and computing statistical power by varying subject size, measured difference between groups and CV. The results indicate that inter-reader variability was 22.5% for microPET and 72.2% for MSFI. Additionally, mean intra-reader variability was 10.1% for microPET and 26.4% for MSFI. Repeated statistical testing showed that a total variability of CV variability has been observed mainly due to differences in the ROI placement and geometry drawn between readers, which may adversely affect statistical power and erroneously lead to negative study outcomes.

Analysis of Intra- and Intersubject Variability in Oral Drug Absorption in Human Bioequivalence Studies of 113 Generic Products.

Science.gov (United States)

Sugihara, Masahisa; Takeuchi, Susumu; Sugita, Masaru; Higaki, Kazutaka; Kataoka, Makoto; Yamashita, Shinji

2015-12-07

In this study, the data of 113 human bioequivalence (BE) studies of immediate release (IR) formulations of 74 active pharmaceutical ingredients (APIs) conducted at Sawai Pharmaceutical Co., Ltd., was analyzed to understand the factors affecting intra- and intersubject variabilities in oral drug absorption. The ANOVA CV (%) calculated from area under the time-concentration curve (AUC) in each BE study was used as an index of intrasubject variability (Vintra), and the relative standard deviation (%) in AUC was used as that of intersubject variability (Vinter). Although no significant correlation was observed between Vintra and Vinter of all drugs, Vintra of class 3 drugs was found to increase in association with a decrease in drug permeability (P(eff)). Since the absorption of class 3 drugs was rate-limited by the permeability, it was suggested that, for such drugs, the low P(eff) might be a risk factor to cause a large intrasubject variability. To consider the impact of poor water solubility on the variability in BE study, a parameter of P(eff)/Do (Do; dose number) was defined to discriminate the solubility-limited and dissolution-rate-limited absorption of class 2 drugs. It was found that the class 2 drugs with a solubility-limited absorption (P(eff)/Do high intrasubject variability. Furthermore, as a reason for high intra- or intersubject variability in AUC for class 1 drugs, effects of drug metabolizing enzymes were investigated. It was demonstrated that intrasubject variability was high for drugs metabolized by CYP3A4 while intersubject variability was high for drugs metabolized by CYP2D6. For CYP3A4 substrate drugs, the Km value showed the significant relation with Vintra, indicating that the affinity to the enzyme can be a parameter to predict the risk of high intrasubject variability. In conclusion, by analyzing the in house data of human BE study, low permeability, solubility-limited absorption, and high affinity to CYP3A4 are identified as risk factors for

Drivers of Intra-Summer Seasonality and Daily Variability of Coastal Low Cloudiness in California Subregions

Science.gov (United States)

Schwartz, R. E.; Iacobellis, S.; Gershunov, A.; Williams, P.; Cayan, D. R.

2014-12-01

Summertime low cloud intrusion into the terrestrial west coast of North America impacts human, ecological, and logistical systems. Over a broad region of the West Coast, summer (May - September) coastal low cloudiness (CLC) varies coherently on interannual to interdecadal timescales and has been found to be organized by North Pacific sea surface temperature. Broad-scale studies of low stratiform cloudiness over ocean basins also find that the season of maximum low stratus corresponds to the season of maximum lower tropospheric stability (LTS) or estimated inversion strength. We utilize a 18-summer record of CLC derived from NASA/NOAA Geostationary Operational Environmental Satellite (GOES) at 4km resolution over California (CA) to make a more nuanced spatial and temporal examination of intra-summer variability in CLC and its drivers. We find that uniform spatial coherency over CA is not apparent for intra-summer variability in CLC. On monthly to daily timescales, at least two distinct subregions of coastal California (CA) can be identified, where relationships between meteorology and stratus variability appear to change throughout summer in each subregion. While north of Point Conception and offshore the timing of maximum CLC is closely coincident with maximum LTS, in the Southern CA Bight and northern Baja region, maximum CLC occurs up to about a month before maximum LTS. It appears that summertime CLC in this southern region is not as strongly related as in the northern region to LTS. In particular, although the relationship is strong in May and June, starting in July the daily relationship between LTS and CLC in the south begins to deteriorate. Preliminary results indicate a moderate association between decreased CLC in the south and increased precipitable water content above 850 hPa on daily time scales beginning in July. Relationships between daily CLC variability and meteorological variables including winds, inland temperatures, relative humidity, and

The role of individual variation in marine larval dispersal

KAUST Repository

Nanninga, Gerrit B.

2014-12-08

The exchange of individuals among patchy habitats plays a central role in spatial ecology and metapopulation dynamics. Dispersal is frequently observed to vary non-randomly within populations (e.g., short vs. long), indicating that variability among individuals may shape heterogeneity in patterns of connectivity. The concept of context- and condition-dependent dispersal describes the balance between the costs and benefits of dispersal that arises from the interaction of temporal and spatial landscape heterogeneity (the context) with phenotypic variability among individuals (the condition). While this hypothesis is widely accepted in terrestrial theory, it remains questionable to what extent the concept of adaptive dispersal strategies may apply to marine larval dispersal, a process that is largely determined by stochastic forces. Yet, larvae of many taxa exhibit strong navigational capabilities and there is mounting evidence of widespread intra-specific variability in biological traits that are potentially correlated with dispersal potential. While so far there are few known examples of real larval dispersal polymorphisms, intra-specifically variable dispersal strategies may be common in marine systems. Whether adaptive or not, it is becoming apparent that inter-individual heterogeneity in morphology, behavior, condition, and life history traits may have critical effects on population-level heterogeneity in dispersal. Here, we explore the eco-evolutionary causes and consequences of intrinsic and extrinsic variability on larval dispersal by synthesizing the existing literature and drawing conceptual parallels from terrestrial theory. We emphasize the potential importance of larval dispersal polymorphisms in marine population dynamics.

Intra- and inter-subject variation in lower limb coordination during countermovement jumps in children and adults

DEFF Research Database (Denmark)

Raffalt, Peter C; Alkjær, Tine; Simonsen, Erik B

2016-01-01

-subject variability. Based on these results, it was concluded that the same movement solutions were available to both age groups, but the children were less able to consistently utilize the individually chosen coordination pattern. Thus, this ability appears to be developed through normal ontogenesis.......The purpose of the present study was to investigate the coordination pattern and coordination variability (intra-subject and inter-subject) in children and adults during vertical countermovement jumps. Ten children (mean age: 11.5±1.8years) and ten adults (mean age: 26.1±4.9years) participated...... in the experiment. Lower body 3D-kinematics and kinetics from both legs were obtained during 9 vertical jumps of each subject. Coordination pattern and coordination variability of intra-limb and inter-limb coupling were established by modified vector coding and continuous relative phase. The adult group jumped...

Relationship between mind and brain: A proposal of solution based on forms of intra- and extra-individual negentropy

Directory of Open Access Journals (Sweden)

Alberto A. Alegre

2015-03-01

Full Text Available It is proposed that the problem of the mind-brain relationship can be overcome by a non-classical materialistic model of personality based on the information defined as a special form of negentropy with a structure and activity, which in five intra-individual categories, organizes all and each of the levels of the personality, and, in an extra-individual category organizes the society. This concept of information leads to a monistic view of the universe and turns into conceptions of society, personality, consciousness, and mental activity based on a theoretical framework that explains the nature of the social individual.

[Effects of situational and individual variables on critical thinking expression].

Science.gov (United States)

Tanaka, Yuko; Kusumi, Takashi

2016-04-01

The present study examined when people decide to choose an expression that is based on critical thinking, and how situational and individual variables affect such a decision process. Given a conversation scenario including overgeneralization with two friends, participants decided whether to follow the conversation by a critical-thinking expression or not. The authors controlled purpose and topic as situational variables, and measured critical-thinking ability, critical-thinking disposition, and self-monitoring as individual variables. We conducted an experiment in which the situational variables were counterbalanced in a within-subject design with 60 university students. The results of logistic regression analysis showed differences within individuals in the decision process whether to choose a critical-thinking expression, and that some situational factors and some subscales of the individual measurements were related to the differences.

Relational trustworthiness: how status affects intra-organizational inequality in job autonomy.

Science.gov (United States)

Campos-Castillo, Celeste; Ewoodzie, Kwesi

2014-03-01

Recent accounts of trustworthiness have moved away from treating it as a stable, individual-level attribute toward viewing it as a variable situated in a relational context, but have not been formalized or supported empirically. We extend status characteristics theory (SCT) to develop formal propositions about relational trustworthiness. We posit that members of task- and collectively oriented groups (non-consciously) infer three qualities from their relative status that are commonly used to determine an individual's trustworthiness: ability, benevolence, and integrity. We apply our formalization to clarify ambiguities regarding intra-organizational job autonomy inequality, thereby linking SCT to broader disparities rooted in job autonomy. We analyze data from a vignette experiment and the General Social Survey to test incrementally how well our propositions generalize across different settings and populations. Results generally support our proposed links between status and intra-organizational job autonomy. We discuss implications for SCT in understanding broader patterns of inequalities. Copyright © 2013 Elsevier Inc. All rights reserved.

The role of storage capacity in coping with intra-annual runoff variability on a global scale

Science.gov (United States)

Gaupp, Franziska; Hall, Jim; Dadson, Simon

2015-04-01

Intra-annual variability poses a risk to water security in many basins as runoff is unevenly distributed over the year. Areas such as Northern Africa, Australia and the South-Western USA are characterized by a high coefficient of variability of monthly runoff. Analyzing the global risk of water scarcity, this study examines 680 basin-country units (BCUs) (403 river basins divided by country borders). By calculating the water balance for each BCU, the interplay of runoff on the one hand and domestic, industrial and environmental water needs on the other hand is shown. In contrast to other studies on average water scarcity, this work focuses on variability of water supply as metrics based on annual average water availability and demand can underestimate the risk of scarcity. The model is based on the assumption that each country-basin with sub-basins and tributaries can be treated as one single reservoir with storage capacity aggregated over that BCU. It includes surface runoff and the possibility to withdraw groundwater as water supply. The storage capacity of each BCU represents the ability to transfer water from wet months to dry months in order to buffer and cope with intra-annual water supply variability and to meet total water demand. Average monthly surface runoff per country-basin for the period 1979 to 2012 is derived from outcomes of the hydrological model Mac-PDM. Mac-PDM is forced with monthly ERAI-Interim reanalysis climate data on a one degree resolution. Groundwater withdrawal capacity, total water demand and storage capacity are taken from the IMPACT model provided by the International Food Research Institute (IFPRI). Storage refers to any kind of surface reservoir whose water can be managed and used for human activities in the industrial, domestic and agricultural sectors. Groundwater withdrawal capacity refers to the technological capacity to pump water rather than the amount of groundwater available. Total water demand includes consumptive water

Displasia no esôfago de Barrett - concordância intra e interobservador no diagnóstico histopatológico Dysplasia in Barrett's esophagus - intra- and interobserver variability in histopathological diagnosis

Directory of Open Access Journals (Sweden)

César Vivian Lopes

2004-06-01

value of histopathologic diagnosis can be questioned due to its poor intra- and interobserver reproducibility. AIMS: To assess intra- and interobserver variability in the diagnosis of Barrett's dysplasia. MATERIAL AND METHODS: Three-micrometer thick sections from biopsy specimens from 42 patients with Barrett's esophagus were stained with hematoxylin-eosin and PAS-alcian blue. The reading of the slides was carried out blindly in a light microscope. Intra and interobserver variability in the interpretation of the slides was determined by kappa statistics. RESULTS: The number of tissue specimens was 229, with average of 5.45 (1 to 18 fragments for patient. Low grade dysplasia was diagnosed by pathologists in 21.4% to 52.4% of the cases. The intra-observer agreement for the diagnosis of low grade dysplasia was slight (kappa = 0.30. The interobserver agreement for the diagnosis of low grade dysplasia was poor, with kappa scores between 0.05 and 0.16. The diagnosis of dysplasia, with agreement for all pathologists examining the same set of slides, was 14.3%. CONCLUSIONS: Pathologic interpretation of Barrett's dysplasia may be subject to marked intra- and interobserver variabiliaty. Interpretation of low grade dysplasia, as high grade dysplasia, should also be considered for review by two or more pathologists.

Relationship between Mind and Brain: A Proposal of Solution Based on Forms of Intra- and Extra-Individual Negentropy

Science.gov (United States)

Alegre, Alberto A.; Zumaeta, Pablo A.

2015-01-01

It is proposed that the problem of the mind-brain relationship can be overcome by a non-classical materialistic model of personality based on the information defined as a special form of negentropy with a structure and activity, which in five intra-individual categories, organizes all and each of the levels of the personality, and, in an…

Effects of estradiol and progesterone on the variability of the micronucleus assay

International Nuclear Information System (INIS)

Baeyens, Ans; Vandersickel, Veerle; Thierens, Hubert; Ridder, Leo De; Vral, Anne

2005-01-01

To investigate chromosomal radiosensitivity of lymphocytes the micronucleus (MN) assay has been used for many years. The results of these studies suggest the use of the MN assay as a biomarker for cancer predisposition. However, the MN assay has still some limitations associated with the reproducibility and sensitivity. Especially a high intra-individual variability has been observed. An explanation for this high intra-individual variability is not yet available. In literature it is suggested that the high variability among females is attributable to hormonal status. In this study we investigated if the high intra-individual variability in micronucleus formation in lymphocytes of females after in vitro exposure to ionising radiation is caused by variations in hormone levels of estradiol (E2) and progesterone (PROG). For this, the MN assay was performed on blood samples of 18 healthy women during 7 consecutive weeks while the estradiol and progesterone levels were determined at the same time. The MN assay was also examined in cultures of isolated blood lymphocytes with estradiol or progesterone levels added in vitro. The results demonstrated that estradiol and progesterone levels have no influence on the variations in radiation-induced MN yields observed in blood samples of healthy women. These conclusions were confirmed by the 'in vitro' experiments as no correlation between the MN yields and the concentrations of hormones (estradiol or progesterone) added in vitro to isolated lymphocytes cultures was observed

Individual canine Airway Response Variability to a Deep Inspiration

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Robert H. Brown

2011-01-01

Full Text Available In healthy individuals, a DI can reverse (bronchodilation or prevent (bronchoprotection induced airway constriction. For individuals with asthma or COPD, these effects may be attenuated or absent. Previous work showed that the size and duration of a DI affected the subsequent response of the airways. Also, increased airway tone lead to increased airway size variability. The present study examined how a DI affected the temporal variability in individual airway baseline size and after methacholine challenge in dogs using High-Resolution Computed Tomography. Dogs were anesthetized and ventilated, and on 4 separate days, HRCT scans were acquired before and after a DI at baseline and during a continuous intravenous infusion of methacholine (Mch at 3 dose rates (17, 67, and 200 μg/mm. The Coefficient of Variation was used as an index of temporal variability in airway size. We found that at baseline and the lowest dose of Mch, variability decreased immediately and 5 minutes after the DI ( P < 0.0001. In contrast, with higher doses of Mch, the DI caused a variable response. At a rate of 67 μg/min of Mch, the temporal variability increased after 5 minutes, while at a rate of 200 μg/min of Mch, the temporal variability increased immediately after the DI. Increased airway temporal variability has been shown to be associated with asthma. Although the mechanisms underlying this temporal variability are poorly understood, the beneficial effects of a DI to decrease airway temporal variability was eliminated when airway tone was increased. If this effect is absent in asthmatics, this may suggest a possible mechanism for the loss of bronchoprotective and bronchodilatory effects after a DI in asthma.

Ultrafast Mid-Infrared Intra-Excitonic Response of Individualized Single-Walled Carbon Nanotubes

International Nuclear Information System (INIS)

Wang, Jigang; Graham, Matt W.; Ma, Yingzhong; Fleming, Graham R.; Kaindl, Robert A.

2009-01-01

The quasi-1D confinement and reduced screening of photoexcited charges in single-walled carbon nanotubes (SWNTs) entails strongly-enhanced Coulomb interactions and exciton binding energies. Such amplified electron-hole (e-h) correlations have important implications for both fundamental physics and optoelectronic applications of nanotubes. The availability of 'individualized' SWNT ensembles with bright and structured luminescence has rendered specific tube chiralities experimentally accessible. In these samples, evidence for excitonic behavior was found in absorption-luminescence maps, two-photon excited luminescence, or ultrafast carrier dynamics. Here, we report ultrafast mid-infrared (mid-IR) studies of individualized SWNTs, evidencing strong photoinduced absorption around 200 meV in semiconducting tubes of (6,5) and (7,5) chiralities. This manifests the observation of quasi-1D intra-excitonic transitions between different relative-momentum states, in agreement with the binding energy and calculated oscillator strength. Our measurements further reveal a saturation of the photoinduced absorption with increasing phase-space filling of the correlated e-h pairs. The transient mid-IR response represents a new tool, unhindered by restrictions of momentum or interband dipole moment, to investigate the density and dynamics of SWNT excitons.

Growing Region Segmentation Software (GRES) for quantitative magnetic resonance imaging of multiple sclerosis: intra- and inter-observer agreement variability: a comparison with manual contouring method

International Nuclear Information System (INIS)

Parodi, Roberto C.; Sardanelli, Francesco; Renzetti, Paolo; Rosso, Elisabetta; Losacco, Caterina; Ferrari, Alessandra; Levrero, Fabrizio; Pilot, Alberto; Inglese, Matilde; Mancardi, Giovanni L.

2002-01-01

Lesion area measurement in multiple sclerosis (MS) is one of the key points in evaluating the natural history and in monitoring the efficacy of treatments. This study was performed to check the intra- and inter-observer agreement variability of a locally developed Growing Region Segmentation Software (GRES), comparing them to those obtained using manual contouring (MC). From routine 1.5-T MRI study of clinically definite multiple sclerosis patients, 36 lesions seen on proton-density-weighted images (PDWI) and 36 enhancing lesion on Gd-DTPA-BMA-enhanced T1-weighted images (Gd-T1WI) were randomly chosen and were evaluated by three observers. The mean range of lesion size was 9.9-536.0 mm 2 on PDWI and 3.6-57.2 mm 2 on Gd-T1WI. The median intra- and inter-observer agreement were, respectively, 97.1 and 90.0% using GRES on PDWI, 81.0 and 70.0% using MC on PDWI, 88.8 and 80.0% using GRES on Gd-T1WI, and 85.8 and 70.0% using MC on Gd-T1WI. The intra- and inter-observer agreements were significantly greater for GRES compared with MC (P<0.0001 and P=0.0023, respectively) for PDWI, while no difference was found between GRES an MC for Gd-T1WI. The intra-observer variability for GRES was significantly lower on both PDWI (P=0.0001) and Gd-T1WI (P=0.0067), whereas for MC the same result was found only for PDWI (P=0.0147). These data indicate that GRES reduces both the intra- and the inter-observer variability in assessing the area of MS lesions on PDWI and may prove useful in multicentre studies. (orig.)

Assessing the inter- and intra-animal variability of in vivo OsteoProbe skeletal measures in untreated dogs

Directory of Open Access Journals (Sweden)

Erin M.B. McNerny

2016-12-01

Full Text Available The OsteoProbe is a second-generation reference point indentation (RPI device without a reference probe that is designed to simplify RPI testing for clinical use. Successful clinical implementation of the OsteoProbe would benefit from a better understanding of how its output, bone material strength index (BMSi, relates to the material properties of bone and under what conditions it reliably correlates with fracture risk. Large animal models have the potential to help fill this knowledge gap, as cadaveric studies are retrospective and limited by incomplete patient histories (including the potential use of bone matrix altering drugs such as bisphosphonates. The goal of this study was to assess the intra and inter-animal variability of OsteoProbe measures in untreated beagle dogs (n = 12, and to evaluate this variability in comparison to traditional mechanical testing. OsteoProbe measurements were performed in vivo on the left tibia of each dog and repeated 6 months later on the day of sacrifice. Within-animal variation of BMSi (CV of 5–10 indents averaged 8.9 and 9.0% at the first and second timepoints, respectively. In contrast, inter-animal variation of BMSi increased from 5.3% to 9.1%. The group variation of BMSi was on par with that of traditional 3-point mechanical testing; inter-animal variation was 10% for ultimate force, 13% for stiffness, and 12% for total work as measured on the femur. There was no significant change in mean BMSi after 6 months, but the individual change with time across the 12 dogs was highly variable, ranging from −12.4% to +21.7% (mean 1.6%, SD 10.6%. No significant correlations were found between in vivo tibia BMSi and femur mechanical properties measured by ex vivo 3-pt bending, but this may be a limitation of sample size or the tests being performed on different bones. No relationship was found between BMSi and tissue mineral density, but a strong positive correlation was found between BMSi and tibia

Intra- and interobserver variability of thyroid volume measurements in healthy adults by 2D versus 3D ultrasound

International Nuclear Information System (INIS)

Andermann, P.; Schloegl, S.; Maeder, U.; Luster, M.; Lassmann, M.; Reiners, C.

2007-01-01

Thyroid volume measurement by ultrasonography (US) is essential in numerous clinical diagnostic and therapeutic fields. While known to be limited, the accuracy and precision of two-dimensional (2D) US thyroid volume measurement have not been thoroughly characterized. Objective: We sought to assess the intra- and interobserver variability, accuracy and precision of thyroid volume determination by conventional 2D US in healthy adults using reference volumes determined by three-dimensional (3D) US. Design, methods: In a prospective blinded trial, thyroid volumes of ten volunteers were determined repeatedly by nine experienced sonographers using conventional 2D US (ellipsoid model). The values obtained were statistically compared to the so-called true volumes determined by 3D US (multiplanar approximation), the so-called gold standard, to estimate systematic errors and relative deviations of individual observers. Results: The standard error of measurement (SEM) for one observer and successive measurements (intraobserver variability), was 14%, and for different observers and repeated measurements (interobserver variability), 17%. The minimum relative thyroid volume change significantly different at the 95% level was 39% for the same observer and 46% for different observers. Regarding accuracy, the mean value of the differences showed a significant thyroid volume overestimation (17%, p <0.01) by 2D relative to 3D US. Conclusion: 2D US is appropriate for routine thyroid volumetry. Nevertheless, the so-called human factor (random error) should be kept in mind and correction is needed for methodical bias (systematic error). Further efforts are required to improve the accuracy and precision of 2D US thyroid volumetry by optimizing the underlying geometrical modeling or by the application of 3D US. (orig.)

Chromosomal radiosensitivity: a study of the chromosomal G2 assay in human blood lymphocytes indicating significant inter-individual variability

International Nuclear Information System (INIS)

Smart, V.; Curwen, G.B.; Whitehouse, C.A.; Edwards, A.; Tawn, E.J.

2003-01-01

The G 2 chromosomal radiosensitivity assay is a technically demanding assay. To ensure that it is reproducible in our laboratory, we have examined the effects of storage and culture conditions by applying the assay to a group of healthy controls and determined the extent of intra- and inter-individual variations. Nineteen different individuals provided one or more blood samples resulting in a total of 57 successful tests. Multiple cultures from a single blood sample showed no statistically significant difference in the number of chromatid type aberrations between cultures. A 24 h delay prior to culturing the lymphocytes did not significantly affect the induced G 2 score. Intra-individual variation was not statistically significant in seven out of nine individuals. Inter-individual variation was highly statistically significant (P<0.001), indicating that there is a real difference between individuals in the response to radiation using this assay

Assessing variability in chemical acute toxicity of unionid mussels: Influence of intra- and inter-laboratory testing, life stage, and species - SETAC Abstract

Science.gov (United States)

We developed a toxicity database for unionid mussels to examine the extent of intra- and inter-laboratory variability in acute toxicity tests with mussel larvae (glochidia) and juveniles; the extent of differential sensitivity of the two life stages; and the variation in sensitiv...

Joint dynamics and intra-subject variability during countermovement jumps in children and adults

DEFF Research Database (Denmark)

Raffalt, Peter C; Alkjær, Tine; Simonsen, Erik B

2016-01-01

The present study investigated lower limb joint work, lower limb joint energy transport and intra-subject variation of the joint dynamics during countermovement jumps in children and adults. Twelve healthy men and eleven healthy boys performed ten maximal countermovement jumps. Three dimensional...... kinematics and kinetics were recorded in synchrony. Hip, knee and ankle joint eccentric and concentric work, joint energy transfer, intra-subject variation of joint moment, joint power and joint moment components were calculated. The children had lower eccentric and concentric hip work and lower eccentric...... work, hip joint moment and hip and knee joint power. Higher intra-subject variation was observed in horizontal joint reaction force components for the children and higher intra-subject variation in the segment angular inertia components was observed for the adults. The joint dynamics of children during...

Intra- and Inter-Individual Differences in Adolescent Depressive Mood: the Role of Relationships with Parents and Friends

OpenAIRE

Zhang, S. (Shiyu); Baams, L. (Laura); van de Bongardt, D. (Daphne); Dubas, J.S. (Judith Semon)

2017-01-01

textabstractUtilizing four waves of data from 1126 secondary school Dutch adolescents (Mage = 13.95 at the first wave; 53% boys), the current study examined the interplay between parent-adolescent and friend-adolescent relationship quality (satisfaction and conflict) in relation to adolescents’ depressive mood. Using multilevel analyses, the interacting effects of parent/friend relationship quality on depressive mood were tested at both the intra- and inter-individual level. Analyses at the i...

Population Pharmacokinetics of Artesunate and Dihydroartemisinin following Intra-Rectal Dosing of Artesunate in Malaria Patients

Science.gov (United States)

Simpson, Julie A; Agbenyega, Tsiri; Barnes, Karen I; Perri, Gianni Di; Folb, Peter; Gomes, Melba; Krishna, Sanjeev; Krudsood, Srivicha; Looareesuwan, Sornchai; Mansor, Sharif; McIlleron, Helen; Miller, Raymond; Molyneux, Malcolm; Mwenechanya, James; Navaratnam, Visweswaran; Nosten, Francois; Olliaro, Piero; Pang, Lorrin; Ribeiro, Isabela; Tembo, Madalitso; van Vugt, Michele; Ward, Steve; Weerasuriya, Kris; Win, Kyaw; White, Nicholas J

2006-01-01

Background Intra-rectal artesunate has been developed as a potentially life-saving treatment of severe malaria in rural village settings where administration of parenteral antimalarial drugs is not possible. We studied the population pharmacokinetics of intra-rectal artesunate and the relationship with parasitological responses in patients with moderately severe falciparum malaria. Methods and Findings Adults and children in Africa and Southeast Asia with moderately severe malaria were recruited in two Phase II studies (12 adults from Southeast Asia and 11 children from Africa) with intensive sampling protocols, and three Phase III studies (44 children from Southeast Asia, and 86 children and 26 adults from Africa) with sparse sampling. All patients received 10 mg/kg artesunate as a single intra-rectal dose of suppositories. Venous blood samples were taken during a period of 24 h following dosing. Plasma artesunate and dihydroartemisinin (DHA, the main biologically active metabolite) concentrations were measured by high-performance liquid chromatography with electrochemical detection. The pharmacokinetic properties of DHA were determined using nonlinear mixed-effects modelling. Artesunate is rapidly hydrolysed in vivo to DHA, and this contributes the majority of antimalarial activity. For DHA, a one-compartment model assuming complete conversion from artesunate and first-order appearance and elimination kinetics gave the best fit to the data. The mean population estimate of apparent clearance (CL/F) was 2.64 (l/kg/h) with 66% inter-individual variability. The apparent volume of distribution (V/F) was 2.75 (l/kg) with 96% inter-individual variability. The estimated DHA population mean elimination half-life was 43 min. Gender was associated with increased mean CL/F by 1.14 (95% CI: 0.36–1.92) (l/kg/h) for a male compared with a female, and weight was positively associated with V/F. Larger V/Fs were observed for the patients requiring early rescue treatment compared

Population pharmacokinetics of artesunate and dihydroartemisinin following intra-rectal dosing of artesunate in malaria patients.

Directory of Open Access Journals (Sweden)

Julie A Simpson

2006-11-01

Full Text Available Intra-rectal artesunate has been developed as a potentially life-saving treatment of severe malaria in rural village settings where administration of parenteral antimalarial drugs is not possible. We studied the population pharmacokinetics of intra-rectal artesunate and the relationship with parasitological responses in patients with moderately severe falciparum malaria.Adults and children in Africa and Southeast Asia with moderately severe malaria were recruited in two Phase II studies (12 adults from Southeast Asia and 11 children from Africa with intensive sampling protocols, and three Phase III studies (44 children from Southeast Asia, and 86 children and 26 adults from Africa with sparse sampling. All patients received 10 mg/kg artesunate as a single intra-rectal dose of suppositories. Venous blood samples were taken during a period of 24 h following dosing. Plasma artesunate and dihydroartemisinin (DHA, the main biologically active metabolite concentrations were measured by high-performance liquid chromatography with electrochemical detection. The pharmacokinetic properties of DHA were determined using nonlinear mixed-effects modelling. Artesunate is rapidly hydrolysed in vivo to DHA, and this contributes the majority of antimalarial activity. For DHA, a one-compartment model assuming complete conversion from artesunate and first-order appearance and elimination kinetics gave the best fit to the data. The mean population estimate of apparent clearance (CL/F was 2.64 (l/kg/h with 66% inter-individual variability. The apparent volume of distribution (V/F was 2.75 (l/kg with 96% inter-individual variability. The estimated DHA population mean elimination half-life was 43 min. Gender was associated with increased mean CL/F by 1.14 (95% CI: 0.36-1.92 (l/kg/h for a male compared with a female, and weight was positively associated with V/F. Larger V/Fs were observed for the patients requiring early rescue treatment compared with the remainder

Population pharmacokinetics of artesunate and dihydroartemisinin following intra-rectal dosing of artesunate in malaria patients.

Science.gov (United States)

Simpson, Julie A; Agbenyega, Tsiri; Barnes, Karen I; Di Perri, Gianni; Folb, Peter; Gomes, Melba; Krishna, Sanjeev; Krudsood, Srivicha; Looareesuwan, Sornchai; Mansor, Sharif; McIlleron, Helen; Miller, Raymond; Molyneux, Malcolm; Mwenechanya, James; Navaratnam, Visweswaran; Nosten, Francois; Olliaro, Piero; Pang, Lorrin; Ribeiro, Isabela; Tembo, Madalitso; van Vugt, Michele; Ward, Steve; Weerasuriya, Kris; Win, Kyaw; White, Nicholas J

2006-11-01

Intra-rectal artesunate has been developed as a potentially life-saving treatment of severe malaria in rural village settings where administration of parenteral antimalarial drugs is not possible. We studied the population pharmacokinetics of intra-rectal artesunate and the relationship with parasitological responses in patients with moderately severe falciparum malaria. Adults and children in Africa and Southeast Asia with moderately severe malaria were recruited in two Phase II studies (12 adults from Southeast Asia and 11 children from Africa) with intensive sampling protocols, and three Phase III studies (44 children from Southeast Asia, and 86 children and 26 adults from Africa) with sparse sampling. All patients received 10 mg/kg artesunate as a single intra-rectal dose of suppositories. Venous blood samples were taken during a period of 24 h following dosing. Plasma artesunate and dihydroartemisinin (DHA, the main biologically active metabolite) concentrations were measured by high-performance liquid chromatography with electrochemical detection. The pharmacokinetic properties of DHA were determined using nonlinear mixed-effects modelling. Artesunate is rapidly hydrolysed in vivo to DHA, and this contributes the majority of antimalarial activity. For DHA, a one-compartment model assuming complete conversion from artesunate and first-order appearance and elimination kinetics gave the best fit to the data. The mean population estimate of apparent clearance (CL/F) was 2.64 (l/kg/h) with 66% inter-individual variability. The apparent volume of distribution (V/F) was 2.75 (l/kg) with 96% inter-individual variability. The estimated DHA population mean elimination half-life was 43 min. Gender was associated with increased mean CL/F by 1.14 (95% CI: 0.36-1.92) (l/kg/h) for a male compared with a female, and weight was positively associated with V/F. Larger V/Fs were observed for the patients requiring early rescue treatment compared with the remainder, independent

Time dependent analysis of assay comparability: a novel approach to understand intra- and inter-site variability over time

Science.gov (United States)

Winiwarter, Susanne; Middleton, Brian; Jones, Barry; Courtney, Paul; Lindmark, Bo; Page, Ken M.; Clark, Alan; Landqvist, Claire

2015-09-01

We demonstrate here a novel use of statistical tools to study intra- and inter-site assay variability of five early drug metabolism and pharmacokinetics in vitro assays over time. Firstly, a tool for process control is presented. It shows the overall assay variability but allows also the following of changes due to assay adjustments and can additionally highlight other, potentially unexpected variations. Secondly, we define the minimum discriminatory difference/ratio to support projects to understand how experimental values measured at different sites at a given time can be compared. Such discriminatory values are calculated for 3 month periods and followed over time for each assay. Again assay modifications, especially assay harmonization efforts, can be noted. Both the process control tool and the variability estimates are based on the results of control compounds tested every time an assay is run. Variability estimates for a limited set of project compounds were computed as well and found to be comparable. This analysis reinforces the need to consider assay variability in decision making, compound ranking and in silico modeling.

Preliminary results of a prospective study of inter- and intra-user variability of the Royal Veterinary College corneal clarity score (RVC-CCS) for use in veterinary practice.

Science.gov (United States)

Sanchez, Rick F; Dawson, Charlotte; Matas Riera, Màrian; Escanilla, Natàlia

2016-07-01

To introduce a new corneal clarity score for use in small animals and describe its inter- and intra-user variability. Twelve dogs and two cats with corneal abnormalities and five dogs with healthy corneas. Four examiners scored every patient twice and never consecutively, focusing on the central cornea. The peripheral cornea was scored separately. The following scoring system was used to describe corneal clarity: G0: no fundus reflection is visible on retroillumination (RI) using a head-mounted indirect ophthalmoscope. G1: a fundus reflection is visible with RI. G2: a 0.1-mm diameter light beam is visible on the anterior surface of the iris and/or lens. G3: gross fundic features are visible when viewed with indirect ophthalmoscopy (IO) using a head-mounted indirect ophthalmoscope and a hand-held 30D lens, although fine details are not clear. G4: fine details of the fundic features are clearly visible with IO. The minimum grades given were analyzed for inter- and intra-user variability with kappa analysis. Intra- and interuser variability of the central corneal clarity ranged from 0.78 to 0.96, showing substantial to almost perfect reproducibility, and from 0.66 to 0.91, showing substantial to almost perfect reliability, respectively. Intra- and interuser variability of the peripheral cornea ranged from 0.83 to 0.95, showing almost perfect agreement, and from 0.53 to 0.91, showing moderate to almost perfect agreement. The RVC-CCS is well suited to assess and monitor central corneal clarity in small animals and to compare outcomes between studies and different surgeons. © 2015 American College of Veterinary Ophthalmologists.

Investigating the Neural Bases for Intra-Subject Cognitive Efficiency Using Functional Magnetic Resonance Imaging

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Neena K. Rao

2014-10-01

Full Text Available Several fMRI studies have examined brain regions mediating inter-subject variability in cognitive efficiency, but none have examined regions mediating intra-subject variability in efficiency. Thus, the present study was designed to identify brain regions involved in intra-subject variability in cognitive efficiency via participant-level correlations between trial-level reaction time (RT and trial-level fMRI BOLD percent signal change on a processing speed task. On each trial, participants indicated whether a digit-symbol probe-pair was present or absent in an array of nine digit-symbol probe-pairs while fMRI data were collected. Deconvolution analyses, using RT time-series models (derived from the proportional scaling of an event-related hemodynamic response function model by trial-level RT, were used to evaluate relationships between trial-level RTs and BOLD percent signal change. Although task-related patterns of activation and deactivation were observed in regions including bilateral occipital, bilateral parietal, portions of the medial wall such as the precuneus, default mode network regions including anterior cingulate, posterior cingulate, bilateral temporal, right cerebellum, and right cuneus, RT-BOLD correlations were observed in a more circumscribed set of regions. Positive RT-related patterns, or RT-BOLD correlations where fast RTs were associated with lower BOLD percent signal change, were observed in regions including bilateral occipital, bilateral parietal, and the precuneus. RT-BOLD correlations were not observed in the default mode network indicating a smaller set of regions associated with intra-subject variability in cognitive efficiency. The results are discussed in terms of a distributed area of regions that mediate variability in the cognitive efficiency that might underlie processing speed differences between individuals.

Variability of intra-urban exposure to particulate matter and CO from Asian-type community pollution sources

Science.gov (United States)

Lung, Shih-Chun Candice; Hsiao, Pao-Kuei; Wen, Tzu-Yao; Liu, Chun-Hu; Fu, Chi Betsy; Cheng, Yu-Ting

2014-02-01

Asian residential communities are usually dotted with various spot pollution sources (SPS), such as restaurants, temples, and home factories, with traffic arteries passing through, resulting in higher intra-urban pollution variability compared with their western counterparts. Thus, it is important to characterize spatial variability of pollutant levels in order to assess accurately residents' exposures in their communities. The objectives of this study are to assess the actual pollutant levels and variability within an Asian urban area and to evaluate the influence of vehicle emission and various SPS on the exposure levels within communities. Real-time monitoring was conducted for a total of 123 locations for particulate matter (PM) and CO in Taipei metropolitan, Taiwan. The mean concentrations for PM1, PM2.5, PM10, and CO are 29.8 ± 22.7, 36.0 ± 25.5, 61.9 ± 35.0 μg m-3 and 4.0 ± 2.5 ppm, respectively. The mean values of PM1/PM2.5 and PM2.5/PM10 are 0.80 ± 0.10 and 0.57 ± 0.15, respectively. PM and CO levels at locations near SPS could be increased by 3.5-4.9 times compared with those at background locations. Regression results show that restaurants contribute significantly 6.18, 6.33, 7.27 μg m-3, and 1.64 ppm to community PM1, PM2.5, PM10, and CO levels, respectively; while the contribution from temples are 13.2, 15.1, and 17.2 μg m-3 for PM1, PM2.5 and PM10, respectively. Additionally, construction sites elevate nearby PM10 levels by 14.2 μg m-3. At bus stops and intersections, vehicle emissions increased PM1 and PM2.5 levels by 5 μg m-3. These results demonstrate significant contribution of community sources to air pollution, and thus the importance of assessing intra-community variability in Asian cities for air pollution and health studies. The methodology used is applicable to other Asian countries with similar features.

MRI assessment of bone marrow in children with juvenile idiopathic arthritis: intra- and inter-observer variability

Energy Technology Data Exchange (ETDEWEB)

Tanturri de Horatio, Laura; Barbuti, Domenico; Toma, Paolo [Ospedale Pediatrico Bambino Gesu, Department of Radiology, Rome (Italy); Damasio, Maria Beatrice [Ospedale G. Gaslini, Department of Radiology, Genoa (Italy); Bracaglia, Claudia [Ospedale Pediatrico Bambino Gesu, Department of Paediatrics, Rome (Italy); Lambot-Juhan, Karen [Hopital Necker-Enfants Malades, Department of Radiology, Paris (France); Boavida, Peter [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom); Ording Mueller, Lil-Sofie [University Hospital North Norway, Department of Radiology, Tromsoe (Norway); Malattia, Clara [Ospedale G. Gaslini, Department of Pediatrics, Genoa (Italy); Rava, Lucilla [Ospedale Pediatrico Bambino Gesu, Department of Epidemiology, Rome (Italy); Rosendahl, Karen [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom); Haukeland University Hospital, Department of Pediatric Radiology, Bergen (Norway)

2012-06-15

Bone marrow oedema (BMO) is included in MRI-based scoring systems of disease activity in adults with rheumatoid arthritis. Similar systems in juvenile idiopathic arthritis (JIA) are lacking. To assess the reproducibility in a multi-centre setting of an MRI BMO scoring system in children with JIA. Seventy-six wrist MRIs were read twice, independently, by two experienced paediatric radiologists. BMO was defined as ill-defined lesions within the trabecular bone, returning high and low signal on T2- and T1-weighted images respectively, with or without contrast enhancement. BMO extension was scored for each of 14 bones at the wrist from 0 (none) to 3 (extensive). The intra-observer agreement was moderate to excellent, with weighted kappa ranging from 0.85 to 1.0 and 0.49 to 1.0 (readers 1 and 2 respectively), while the inter-observer agreement ranged from 0.41 to 0.79. The intra- and inter-observer intraclass correlation coefficients were excellent and satisfactory, respectively. The scoring system was reliable and may be used for grading bone marrow abnormality in JIA. The relatively large variability in aggregate scores, particularly between readers, underscores the need for thorough standardisation. (orig.)

MRI assessment of bone marrow in children with juvenile idiopathic arthritis: intra- and inter-observer variability

International Nuclear Information System (INIS)

Tanturri de Horatio, Laura; Barbuti, Domenico; Toma, Paolo; Damasio, Maria Beatrice; Bracaglia, Claudia; Lambot-Juhan, Karen; Boavida, Peter; Ording Mueller, Lil-Sofie; Malattia, Clara; Rava, Lucilla; Rosendahl, Karen

2012-01-01

Bone marrow oedema (BMO) is included in MRI-based scoring systems of disease activity in adults with rheumatoid arthritis. Similar systems in juvenile idiopathic arthritis (JIA) are lacking. To assess the reproducibility in a multi-centre setting of an MRI BMO scoring system in children with JIA. Seventy-six wrist MRIs were read twice, independently, by two experienced paediatric radiologists. BMO was defined as ill-defined lesions within the trabecular bone, returning high and low signal on T2- and T1-weighted images respectively, with or without contrast enhancement. BMO extension was scored for each of 14 bones at the wrist from 0 (none) to 3 (extensive). The intra-observer agreement was moderate to excellent, with weighted kappa ranging from 0.85 to 1.0 and 0.49 to 1.0 (readers 1 and 2 respectively), while the inter-observer agreement ranged from 0.41 to 0.79. The intra- and inter-observer intraclass correlation coefficients were excellent and satisfactory, respectively. The scoring system was reliable and may be used for grading bone marrow abnormality in JIA. The relatively large variability in aggregate scores, particularly between readers, underscores the need for thorough standardisation. (orig.)

How plantar exteroceptive efficiency modulates postural and oculomotor control: inter-individual variability

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Arnaud eFoisy

2016-05-01

Full Text Available In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In order to test this hypothesis, we re-analyzed the data relative to 31 young (age 25,7±3,8 and healthy subjects who participated in the first experiment after having classified them into two groups depending on their Plantar Quotient (PQ = Surface area of CoP foam / Surface area of CoP firm ground x100. Foam decreases the information arising from the feet, normally resulting in a PQ>100. Hence, the PQ provides information on the weight of plantar cutaneous afferents used in postural control. Twelve people were Plantar-Independent Subjects, as indicated by a PQ<100. These individuals did not behave like the Normal Plantar Quotient Subjects: they were almost insensitive to the plantar stimulations in terms of postural control and totally insensitive in terms of oculomotor control. We conclude that the inter-individual variability observed in our first experiment is explained by the subjects’ degree of plantar reliance. We propose that plantar independence is a dysfunctional situation revealing an inefficiency in plantar cutaneous afferents. The latter could be due to a latent somatosensory dysfunction generating a noise which prevents the CNS from correctly processing and using feet somatosensory afferents both for balance and vergence control: Plantar Irritating Stimulus. Considering the non-noxious nature and prevalence of this phenomenon, these results can be of great interest to researchers and clinicians who attempt to trigger postural or oculomotor responses through mechanical stimulation of the foot sole.

Patterns and predictability in the intra-annual organic carbon variability across the boreal and hemiboreal landscape

Science.gov (United States)

Hytteborn, Julia K.; Temnerud, Johan; Alexander, Richard B.; Boyer, Elizabeth W.; Futter, Martyn N.; Fröberg, Mats; Dahné, Joel; Bishop, Kevin H.

2015-01-01

Factors affecting total organic carbon (TOC) concentrations in 215 watercourses across Sweden were investigated using parameter parsimonious regression approaches to explain spatial and temporal variabilities of the TOC water quality responses. We systematically quantified the effects of discharge, seasonality, and long-term trend as factors controlling intra-annual (among year) and inter-annual (within year) variabilities of TOC by evaluating the spatial variability in model coefficients and catchment characteristics (e.g. land cover, retention time, soil type).Catchment area (0.18–47,000 km2) and land cover types (forests, agriculture and alpine terrain) are typical for the boreal and hemiboreal zones across Fennoscandia. Watercourses had at least 6 years of monthly water quality observations between 1990 and 2010. Statistically significant models (p characteristics explained 21% of the spatial variation in the linear trend coefficient, less than 20% of the variation in the discharge coefficient and 73% of the spatial variation in mean TOC. Specific discharge, water residence time, the variance of daily precipitation, and lake area, explained 45% of the spatial variation in the amplitude of the TOC seasonality.Because the main drivers of temporal variability in TOC are seasonality and discharge, first-order estimates of the influences of climatic variability and change on TOC concentration should be predictable if the studied catchments continue to respond similarly.

Individual Educational Paths in the Universities of Russia and Great Britain (Theoretical Aspects

Directory of Open Access Journals (Sweden)

Natalya Yu. Shaposhnikova

2015-01-01

Full Text Available The author highlights the necessity for higher education institutions to form and realize students' individual educational paths in the learning process, which is stated in the Federal Law on Education and FSES HPE of the third generation. The article presents an overview of the different approaches to the definition of the term «individual educational path» (IEP. It also gives a brief overview of the existing terms in the Russian terminological system, which are close in meaning to the term above. The author formulates her own tentative definition of the term «IEP» which is based on the analysis made. The article further addresses the solution to the problem of the individualization of higher education learning process in Great Britain, which is described through the term «Personal Development Planning». The meaning of the term is shown through the set of actions: planning, doing things, recording of the self experience, reviewing and evaluating, using the personal knowledge derived from reflection and self understanding as well as own learning abilities to plan future actions. In conclusion, the meanings of the terms «IEP» and «PDP» are compared. The author emphasires the importance of studying Great Britain's experience - the practice of solving problems connected with the individualization of the university learning process and the possibilities to use it to facilitate the implementation of students' individual educational paths in Russian higher education institutions.

Demographic variability and heterogeneity among individuals within and among clonal bacteria strains

DEFF Research Database (Denmark)

Jouvet, Lionel; Rodriguez-Rojas, Alexandro; Steiner, Ulrich

2018-01-01

to accurately decompose the drivers of heterogeneity among individuals as genetically fixed or selectively neutral. Rather than working on wild populations we present here data from a simple bacterial system in the lab, Escherichia coli. Our system, based on cutting-edge microfluidic techniques, provides high...... control over the genotype and the environment. It therefore allows to unambiguously decompose and quantify fixed genetic variability and dynamic stochastic variability among individuals. We show that within clonal individual variability (dynamic heterogeneity) in lifespan and lifetime reproduction...

Individual Variability in Brain Activity: A Nuisance or an Opportunity?

Science.gov (United States)

Van Horn, John Darrell; Grafton, Scott T; Miller, Michael B

2008-12-01

Functional imaging research has been heavily influenced by results based on population-level inference. However, group average results may belie the unique patterns of activity present in the individual that ordinarily are considered random noise. Recent advances in the evolution of MRI hardware have led to significant improvements in the stability and reproducibility of blood oxygen level dependent (BOLD) measurements. These enhancements provide a unique opportunity for closer examination of individual patterns of brain activity. Three objectives can be accomplished by considering brain scans at the individual level; (1) Mapping functional anatomy at a fine grained analysis; (2) Determining if an individual scan is normative with respect to a reference population; and (3) Understanding the sources of intersubject variability in brain activity. In this review, we detail these objectives, briefly discuss their histories and present recent trends in the analyses of individual variability. Finally, we emphasize the unique opportunities and challenges for understanding individual differences through international collaboration among Pacific Rim investigators.

Intra and interobserver variability of renal allograft ultrasound volume and resistive index measurements

International Nuclear Information System (INIS)

Mancini, Marcello; Liuzzi, Raffaele; Daniele, Stefania; Raffio, Teresa; Salvatore, Marco; Sabbatini, Massimo; Cianciaruso, Bruno; Ferrara, Liberato Aldo

2005-01-01

Purpose: Aim of the presents study was to evaluate the repeatability and reproducibility of the Doppler Resistive Index (R.I.) and the Ultrasound renal volume measurement in renal transplants. Materials and methods: Twenty -six consecutive patients (18 men, 8 women) mean age of 42,8±12,4 years (M±SD)(range 22-65 years) were studied twice by each of two trained sonographers using a color Doppler ultrasound scanner. Twelve of them had a normal allograft function (defined as stable serum creatinine levels ≤123,76 μmol/L), whilst the remaining 14 had decreased allograft function (serum creatinine 132.6-265.2 μmol/L). Results were given as mean of 6 measurements performed at upper, middle and lower pole of the kidney. Intra- and interobserver variability was assessed by the repeatability coefficient and coefficient of variation (CV). Results: Regarding Resistive Index measurement, repeatability coefficient was between 0.04 and 0.06 and the coefficient of variation was [it

Individual diet variation in a marine fish assemblage: Optimal Foraging Theory, Niche Variation Hypothesis and functional identity

Science.gov (United States)

Cachera, M.; Ernande, B.; Villanueva, M. C.; Lefebvre, S.

2017-02-01

Individual diet variation (i.e. diet variation among individuals) impacts intra- and inter-specific interactions. Investigating its sources and relationship with species trophic niche organization is important for understanding community structure and dynamics. Individual diet variation may increase with intra-specific phenotypic (or "individual state") variation and habitat variability, according to Optimal Foraging Theory (OFT), and with species trophic niche width, according to the Niche Variation Hypothesis (NVH). OFT proposes "proximate sources" of individual diet variation such as variations in habitat or size whereas NVH relies on "ultimate sources" related to the competitive balance between intra- and inter-specific competitions. The latter implies as a corollary that species trophic niche overlap, taken as inter-specific competition measure, decreases as species niche width and individual niche variation increase. We tested the complementary predictions of OFT and NVH in a marine fish assemblage using stomach content data and associated trophic niche metrics. The NVH predictions were tested between species of the assemblage and decomposed into a between- and a within-functional group component to assess the potential influence of species' ecological function. For most species, individual diet variation and niche overlap were consistently larger than expected. Individual diet variation increased with intra-specific variability in individual state and habitat, as expected from OFT. It also increased with species niche width but in compliance with the null expectation, thus not supporting the NVH. In contrast, species niche overlap increased significantly less than null expectation with both species niche width and individual diet variation, supporting NVH corollary. The between- and within-functional group components of the NVH relationships were consistent with those between species at the assemblage level. Changing the number of prey categories used to

Intra-individual cognitive imbalance in ASD between perceptual reasoning and ambiguity-solving related to tool use: Comparison among children exhibiting ASD, AD/HD, and typical development.

Science.gov (United States)

Wakusawa, Keisuke; Nara, Chieko; Kubota, Yuki; Tomizawa, Yayoi; Taki, Yasuyuki; Sassa, Yuko; Kobayashi, Satoru; Suzuki-Muromoto, Sato; Hirose, Mieko; Yokoyama, Hiroyuki; Nara, Takahiro; Kure, Shigeo; Mori, Norio; Takei, Noriyoshi; Kawashima, Ryuta

2018-01-01

Several studies have suggested that objective deficits in the processing of abstract information in conjunction with an enhanced ability to process concrete information is a definitive characteristic of autism spectrum disorder (ASD). However, this cognitive imbalance is not necessarily clear in high-functioning autistic individuals who do not display absolute differences relative to typically developing (TD) populations. Thus, the purpose of this study was to identify this cognitive tendency in high-functioning autistic individuals using intra-individual cognitive comparisons. The reaction times (RTs) of TD children, children with ASD, and children with attention deficit hyperactivity disorder (AD/HD) (n=17 in each group, mean age=11.9years, age range=9.8-15.8years) were compared using the Which/How-to-Apply Tools (W/HAT) test, which consists of tasks requiring the adaptive use of novel tools and familiar tools in atypical and typical situations. Differences in RTs between the atypical and typical trials ([A-T]) were used to assess intra-individual cognitive imbalances. As predicted, the [A-T] scores of the ASD group were significantly higher than those of the TD group even though the RTs in the atypical and typical trials did not differ. Additionally, the [A-T] values were significantly higher in the ASD group than in the AD/HD group, which indicates that the cognitive imbalance was specific to ASD individuals. No significant interaction was detected between the trial and subject group. The findings of this study demonstrate that a cognitive imbalance in ASD individuals may enhance the current understanding of the pathophysiology of this disorder, which is found in a range of individuals, including those with obvious cortical dysfunction to those with only intra-individual imbalances. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Ethnic boundaries and personal choice. Assessing the influence of individual inclinations to choose intra-ethnic relationships on pupils' networks : Assessing the influence of individual inclinations to choose intra-ethnic relationships on pupils’ networks

NARCIS (Netherlands)

Baerveldt, C; Van Duijn, MAJ; Vermeij, L; Van Hemert, DA; Hemert, Dianne A. van

The existence of ethnic boundaries in 20 pupils' networks is tested by comparing the proportion of intra-ethnic to inter-ethnic relationships, while controlling for the distribution of intra- and inter-ethnic dyads in pupils' networks. Also, we tested if those boundaries are affected by the

Qualitative ultrasound elastography assessment of benign thyroid nodules: Patterns and intra-observer acquisition variability

International Nuclear Information System (INIS)

Lacout, Alexis; Chevenet, Carole; Thariat, Juliette; Figl, Andrea; Marcy, Pierre-Yves

2013-01-01

To report and evaluate qualitative elastography patterns by using gray-scale and Doppler ultrasound (US) in patients presenting with benign thyroid nodules and to evaluate the reproducibility of US elastography examinations. Institutional review board approval was obtained, and all patients provided informed consent. Over a 3-month time period, all consecutive adult patients were referred to our institution to undergo a thyroid nodule fine-needle aspiration biopsy (FNAB) procedure. Patients presenting with benign cytology according to the Bethesda 2008 classification were prospectively enrolled in the study. Each thyroid nodule was assessed by using gray-scale, Doppler US, and elastography acquisitions by a single operator (A. L.). Multiple elastography acquisitions per thyroid nodule were performed and elastography scorings of the nodules were compared with each other. Nineteen patients (16 women and 3 men, mean age 58 years) with 22 thyroid nodules were included in the present study. Elastographic patterns 1, 2, and 3 were reported (23% nodules showed pattern 3). The elastography pattern showed a strong variability in 13 nodules (59%). The elastography acquisition result variability involved the “malignant” pattern 3 in 36% of cases. Almost one-third of benign thyroid nodules displayed pattern 3 on qualitative US elastography. The intra-observer variability of the benign thyroid elastography scoring is wide, thus limiting the thyroid nodule US examination accuracy. In FNAB-proven benign thyroid nodules, elastography pattern 3 is frequent and cannot be used as a strong indicator of thyroid malignancy

Periorbital biometric measurements using ImageJ software: Standardisation of technique and assessment of intra- and interobserver variability

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R Rajyalakshmi

2017-01-01

Full Text Available Purpose: To assess the reliability and repeatability of periorbital biometric measurements using ImageJ software and to assess if the horizontal visible iris diameter (HVID serves as a reliable scale for facial measurements. Methods: This study was a prospective, single-blind, comparative study. Two clinicians performed 12 periorbital measurements on 100 standardised face photographs. Each individual’s HVID was determined by Orbscan IIz and used as a scale for measurements using ImageJ software. All measurements were repeated using the ‘average’ HVID of the study population as a measurement scale. Intraclass correlation coefficient (ICC and Pearson product-moment coefficient were used as statistical tests to analyse the data. Results: The range of ICC for intra- and interobserver variability was 0.79–0.99 and 0.86–0.99, respectively. Test-retest reliability ranged from 0.66–1.0 to 0.77–0.98, respectively. When average HVID of the study population was used as scale, ICC ranged from 0.83 to 0.99, and the test-retest reliability ranged from 0.83 to 0.96 and the measurements correlated well with recordings done with individual Orbscan HVID measurements. Conclusion: Periorbital biometric measurements using ImageJ software are reproducible and repeatable. Average HVID of the population as measured by Orbscan is a reliable scale for facial measurements.

Intra-Urban Variability in Elemental Carbon Deposition to Tree Canopies

Science.gov (United States)

Barrett, T. E.; Ponette-González, A.; Rindy, J. E.; Sheesley, R. J.

2017-12-01

Urban areas cover biomass combustion, EC is a powerful climate-forcing agent and a significant component of fine particulate matter in urban atmospheres. Thus, understanding the factors that govern EC removal in urban areas could help mitigate climate change, while improving air quality for urban residents. EC particles can be removed from the atmosphere in precipitation (wet and fog deposition) or they can settle directly onto receptor surfaces (dry deposition). Only limited measurements indicate that EC deposition is higher in urban than in rural and remote regions. However, EC deposition likely exhibits considerable intra-urban variability, with tree canopies serving as potentially important sinks for EC on the cityscape. The goal of this research is to quantify spatial variability in total (wet + dry) EC deposition to urban tree canopies in the Dallas-Fort Worth Metroplex. Using a stratified non-random sampling design, 41 oak trees (22 post oak (Quercus stellata) and 19 live oak (Quercus virginiana)) were selected near (100 m) for measurements of throughfall (water that falls from the canopy to the forest floor). Additionally, 16 bulk rainfall samplers were deployed in grassy areas with no canopy cover. Results from one rain event indicate a volume weighted mean concentration of 83 µg EC L-1 in post oak throughfall, 36 µg EC L-1 in live oak throughfall, and 4 µg EC L-1 in bulk rainfall. Total EC deposition to oak tree canopies was 2.0 ± 2.1 (SD) mg m-2 for post oak and 0.7 ± 0.3 mg m-2 for live oak. Bulk rainfall deposition was 0.08 ± 0.1 mg m-2. Our preliminary findings show that trees are effective urban air filters, removing 9-25 times more EC from the atmosphere than rainwater alone. Resolving surface controls on atmospheric EC removal is key to developing and assessing near-term climate and air quality mitigation strategies.

Intra- and interoperator variability of lobar pulmonary volumes and emphysema scores in patients with chronic obstructive pulmonary disease and emphysema: comparison of manual and semi-automated segmentation techniques.

Science.gov (United States)

Molinari, Francesco; Pirronti, Tommaso; Sverzellati, Nicola; Diciotti, Stefano; Amato, Michele; Paolantonio, Guglielmo; Gentile, Luigia; Parapatt, George K; D'Argento, Francesco; Kuhnigk, Jan-Martin

2013-01-01

We aimed to compare the intra- and interoperator variability of lobar volumetry and emphysema scores obtained by semi-automated and manual segmentation techniques in lung emphysema patients. In two sessions held three months apart, two operators performed lobar volumetry of unenhanced chest computed tomography examinations of 47 consecutive patients with chronic obstructive pulmonary disease and lung emphysema. Both operators used the manual and semi-automated segmentation techniques. The intra- and interoperator variability of the volumes and emphysema scores obtained by semi-automated segmentation was compared with the variability obtained by manual segmentation of the five pulmonary lobes. The intra- and interoperator variability of the lobar volumes decreased when using semi-automated lobe segmentation (coefficients of repeatability for the first operator: right upper lobe, 147 vs. 96.3; right middle lobe, 137.7 vs. 73.4; right lower lobe, 89.2 vs. 42.4; left upper lobe, 262.2 vs. 54.8; and left lower lobe, 260.5 vs. 56.5; coefficients of repeatability for the second operator: right upper lobe, 61.4 vs. 48.1; right middle lobe, 56 vs. 46.4; right lower lobe, 26.9 vs. 16.7; left upper lobe, 61.4 vs. 27; and left lower lobe, 63.6 vs. 27.5; coefficients of reproducibility in the interoperator analysis: right upper lobe, 191.3 vs. 102.9; right middle lobe, 219.8 vs. 126.5; right lower lobe, 122.6 vs. 90.1; left upper lobe, 166.9 vs. 68.7; and left lower lobe, 168.7 vs. 71.6). The coefficients of repeatability and reproducibility of emphysema scores also decreased when using semi-automated segmentation and had ranges that varied depending on the target lobe and selected threshold of emphysema. Semi-automated segmentation reduces the intra- and interoperator variability of lobar volumetry and provides a more objective tool than manual technique for quantifying lung volumes and severity of emphysema.

Micro-macro multilevel latent class models with multiple discrete individual-level variables

NARCIS (Netherlands)

Bennink, M.; Croon, M.A.; Kroon, B.; Vermunt, J.K.

2016-01-01

An existing micro-macro method for a single individual-level variable is extended to the multivariate situation by presenting two multilevel latent class models in which multiple discrete individual-level variables are used to explain a group-level outcome. As in the univariate case, the

Intra-seasonal and Inter-annual variability of Bowen Ratio over rain-shadow region of North peninsular India

Science.gov (United States)

Morwal, S. B.; Narkhedkar, S. G.; Padmakumari, B.; Maheskumar, R. S.; Deshpande, C. G.; Kulkarni, J. R.

2017-05-01

Intra-seasonal and inter-annual variability of Bowen Ratio (BR) have been studied over the rain-shadow region of north peninsular India during summer monsoon season. Daily grid point data of latent heat flux (LHF), sensible heat flux (SHF) from NCEP/NCAR Reanalysis for the period 1970-2014 have been used to compute daily area-mean BR. Daily grid point rainfall data at a resolution of 0.25° × 0.25° from APHRODITE's Water Resources for the available period 1970-2007 have been used to study the association between rainfall and BR. The study revealed that BR rapidly decreases from 4.1 to 0.29 in the month of June and then remains nearly constant at the same value (≤0.1) in the rest of the season. High values of BR in the first half of June are indicative of intense thermals and convective clouds with higher bases. Low values of BR from July to September period are indicative of weak thermals and convective clouds with lower bases. Intra-seasonal and inter-annual variability of BR is found to be inversely related to precipitation over the region. BR analysis indicates that the land surface characteristics of the study region during July-September are similar to that over oceanic regions as far as intensity of thermals and associated cloud microphysical properties are concerned. Similar variation of BR is found in El Nino and La Nina years. During June, an increasing trend is observed in SHF and BR and decreasing trend in LHF from 1976 to 2014. Increasing trend in the SHF is statistically significant.

Water baths for farmed mink: intra-individual consistency and inter-individual variation in swimming behaviour, and effects on stereotyped behaviour

Directory of Open Access Journals (Sweden)

J. MONONEN

2008-12-01

Full Text Available Swimming behaviour and effects of water baths on stereotyped behaviour in farmed mink (Mustela vison were studied in three experiments. The singly-housed mink had access from their home cages to extra cages with 20.5 litre water baths. Two short-term experiments aimed to investigate how quickly adult and juvenile mink start using and how consistently they use water baths over 10 days, and whether the extent of the use correlates between dams and their females kits. A four-month experiment was designed to compare the development of stereotyped behaviour in juvenile mink housed with and without swimming opportunity. The behavioural analyses were based on several 24-hour video recordings carried out in all three experiments. There were obvious inter-individual differences and intra-individual consistency in swimming frequency and time. Farmed mink’s motivation to swim can be assessed in short-term experiments, and measurement of water losses from the swimming baths and use of instantaneous sampling with 10 min sampling intervals provide quite reliable measures of the amount of swimming. The bath use of the juveniles correlated with that of their dams, indicating that an individual mink’s eagerness to swim may have a genetic component. The lower amount of stereotyped behaviour in mink housed with water baths indicates that long-term access to baths may alleviate frustration in singly-housed juvenile farmed mink.;

INTRA graphical package - INTRA-Graph 1.0

International Nuclear Information System (INIS)

Hofman, D.; Edlund, O.

2001-04-01

INTRA-Graph 1.0 has been developed at Studsvik Eco and Safety AB in the frame of the European Fusion Technology Programme for application in the safety analysis using the INTRA code. INTRA-Graph 1.0 is a graphical package producing 2-dimensional plots of results generated by the INTRA code. INTRA-Graph 1.0 has been developed by extending the Grace package source code, distributed under the terms of GNU General Public License. The changes in the Grace source files are limited to provide easy updates of the INTRA-Graph when a new version of Grace will be released. The INTRA-related functionality has been implemented in new source files. The present report describes and gives complete listing of these files. The changes in the Grace source files are also described and the listing of the changed parts of the files is presented. The report gives detailed explanations and examples of files required for installation and configuration of INTRA-Graph on the different types of Unix workstations

DEMOGRAPHIC VARIABLES INFLUENCING INDIVIDUAL ENTREPRENEURIAL ORIENTATION AND STRATEGIC THINKING CAPABILITY

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Lara Jelenc

2016-03-01

Full Text Available Strategic thinking capability is interesting part of the cognitive development of each entrepreneur. This paper develops on notion that there a number of demographic variables that shape the behavior of each particular elements of entrepreneurial orientation and strategic component of each entrepreneur. The demographic variable that have significant role will take the role of moderator in further research. Since both constructs are multidimensional, the demographic variables are not influencing them in the same way. The empirical research has been performed on IT firms in Croatia in 2014. Individual entrepreneurial orientation is measured by the construct developed by Bolton and Lane’s (2012 individual entrepreneurial orientation instrument. The instrument is grounded in the seminal work of Miller (1983, Covin and Slevin (1986; 1988; 1989, Lumpkin and Dess (1996 and Covin and Wales (2011; consisting of three dimensions – risk-taking, innovation, and proactiveness. Strategic thinking was measured by Pisapia’s (2009 Strategic thinking questionnaire (STQ. The STQ asked respondents to rate how often they use systems thinking, reframing, and reflecting skills. Within the framework of individual entrepreneurial orientation the following demographic variables shape the trends: age, gender, education abroad and previous experience. Entrepreneurs between 40-60 years old are less prone to risk, female entrepreneurs are more proactive than men, education abroad provides with the additional proactiveness and the entrepreneur with previous experience is prone to higher risk, proactiveness and innovativeness. Within the framework of strategic thinking capability the following demographic variables shape the trends: age, gender, education and experience. Entrepreneurs older than 60 score high on system thinking as well as females, females also score higher on reframing. Entrepreneurs with PhD degree score lower on reframing, while managers working more

Individual variability in the venom proteome of juvenile Bothrops jararaca specimens.

Science.gov (United States)

Dias, Gabriela S; Kitano, Eduardo S; Pagotto, Ana H; Sant'anna, Sávio S; Rocha, Marisa M T; Zelanis, André; Serrano, Solange M T

2013-10-04

Snake venom proteomes/peptidomes are highly complex and subject to ontogenetic changes. Individual variation in the venom proteome of juvenile snakes is poorly known. We report the proteomic analysis of venoms from 21 juvenile specimens of Bothrops jararaca of different geographical origins and correlate it with the evaluation of important venom features. Individual venoms showed similar caseinolytic activities; however, their amidolytic activities were significantly different. Rather intriguingly, plasma coagulant activity showed remarkable variability among the venoms but not the prothrombin-activating activity. LC-MS analysis showed significant differences between venoms; however, an interesting finding was the ubiquitous presence of the tripeptide ZKW, an endogenous inhibitor of metalloproteinases. Electrophoretic profiles of proteins submitted to reduction showed significant variability in total proteins, glycoproteins, and in the subproteomes of proteinases. Moreover, identification of differential bands revealed variation in most B. jararaca toxin classes. Profiles of venoms analyzed under nonreducing conditions showed less individual variability and identification of proteins in a conserved band revealed the presence of metalloproteinases and l-amino acid oxidase as common components of these venoms. Taken together, our findings suggest that individual venom proteome variability in B. jararaca exists from a very early animal age and is not a result of ontogenetic and diet changes.

Variability of insulin-stimulated myocardial glucose uptake in healthy elderly subjects

DEFF Research Database (Denmark)

Kofoed, Klaus F; Hove, Jens D; Freiberg, Jacob

2002-01-01

The aim of this study was to assess regional and global variability of insulin-stimulated myocardial glucose uptake in healthy elderly subjects and to evaluate potentially responsible factors. Twenty men with a mean age of 64 years, no history of cardiovascular disease, and normal blood pressure...... rest and hyperaemic blood flow during dipyridamole infusion were measured with nitrogen-13 ammonia and positron emission tomography in 16 left ventricular myocardial segments. Intra-individual and inter-individual variability of insulin-stimulated myocardial glucose uptake [relative dispersion...... = (standard deviation/mean)] was 13% and 29% respectively. Although inter-individual variability of glucose uptake and blood flow at rest was of the same magnitude, no correlation was found between these measures. Regional and global insulin-stimulated myocardial glucose uptake correlated linearly with whole...

Three-dimensional echocardiography: assessment of inter- and intra-operator variability and accuracy in the measurement of left ventricular cavity volume and myocardial mass

International Nuclear Information System (INIS)

Nadkarni, S.K.; Drangova, M.; Boughner, D.R.; Fenster, A.; Department of Medical Biophysics, Medical Sciences Building, University of Western Ontario, London, Ontario N6A 5C1

2000-01-01

Accurate left ventricular (LV) volume and mass estimation is a strong predictor of cardiovascular morbidity and mortality. We propose that our technique of 3D echocardiography provides an accurate quantification of LV volume and mass by the reconstruction of 2D images into 3D volumes, thus avoiding the need for geometric assumptions. We compared the accuracy and variability in LV volume and mass measurement using 3D echocardiography with 2D echocardiography, using in vitro studies. Six operators measured the LV volume and mass of seven porcine hearts, using both 3D and 2D techniques. Regression analysis was used to test the accuracy of results and an ANOVA test was used to compute variability in measurement. LV volume measurement accuracy was 9.8% (3D) and 18.4% (2D); LV mass measurement accuracy was 5% (3D) and 9.2% (2D). Variability in LV volume quantification with 3D echocardiography was %SEM inter = 13.5%, %SEM intra = 11.4%, and for 2D echocardiography was %SEM inter = 21.5%, %SEM intra = 19.1%. We derived an equation to predict uncertainty in measurement of LV volume and mass using 3D echocardiography, the results of which agreed with our experimental results to within 13%. 3D echocardiography provided twice the accuracy for LV volume and mass measurement and half the variability for LV volume measurement as compared with 2D echocardiography. (author)

Effect Of Variable Practice On The Motor Learning Process In Manual Wheelchair Propulsion

NARCIS (Netherlands)

Leving, Marika T; Vegter, Riemer J K; de Groot, Sonja; van der Woude, Lucas H V

Handrim wheelchair propulsion is a cyclic skill that needs to be learned during rehabilitation. It has been suggested that a higher intra-individual variability benefits the motor learning process of wheelchair propulsion. PURPOSE: The goal of the current study was to determine the effect of

Intra-individual comparison of different contrast media concentrations (300 mg, 370 mg and 400 mg iodine) in MDCT

Energy Technology Data Exchange (ETDEWEB)

Behrendt, Florian F.; Keil, Sebastian; Plumhans, Cedric; Guenther, Rolf W. [RWTH Aachen University, Department of Diagnostic Radiology, University Hospital, Aachen (Germany); Pietsch, Hubertus; Jost, Gregor; Sieber, Martin A.; Seidensticker, Peter [Bayer Schering Pharma AG, Berlin (Germany); Mahnken, Andreas H. [RWTH Aachen University, Department of Diagnostic Radiology, University Hospital, Aachen (Germany); RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute for Biomedical Engineering, Aachen (Germany)

2010-07-15

To compare intra-individual contrast enhancement in multi-detector-row computed tomography (MDCT) using contrast media (CM) containing 300, 370 and 400 mg iodine per ml (mgI/ml). Six pigs underwent repeated chest MDCT using three different CM (iopromide 300, iopromide 370, iomeprol 400). An identical iodine delivery (IDR) rate of 1.5 gI/s and a constant total iodine dose of 300 mg/kg body weight were used. Dynamic CT were acquired at the level of the pulmonary artery, and the ascending and descending aorta. After the time enhancement curves were computed, the pulmonary and aortic peak enhancement, time to peak and plateau time above 300 HU were calculated. Intra-individual peak contrast enhancement was significantly higher for the 300 mgI/ml contrast medium compared with the 370 and 400 mgI/ml media: pulmonary trunk 595 HU vs 516 HU (p = 0.0093) vs 472HU (p = 0.0005), and aorta 505 HU vs 454 HU (p = 0.0008) vs 439 HU (p = 0.0001), respectively. Comparison of time to peaks showed no significant difference. Plateau times were significantly longer for the 300 mgI/ml than for the 370 and 400 mgI/ml CM at all anatomical sites. Given normalised IDR and total iodine burden, the use of CM with a standard concentration with 300 mg iodine/ml provides improved contrast enhancement compared with highly concentrated CM in the chest. (orig.)

Imaging Brain Development: Benefiting from Individual Variability

Directory of Open Access Journals (Sweden)

Megha Sharda

2015-01-01

Full Text Available Human brain development is a complex process that evolves from early childhood to young adulthood. Major advances in brain imaging are increasingly being used to characterize the developing brain. These advances have further helped to elucidate the dynamic maturational processes that lead to the emergence of complex cognitive abilities in both typical and atypical development. However, conventional approaches involve categorical group comparison models and tend to disregard the role of widespread interindividual variability in brain development. This review highlights how this variability can inform our understanding of developmental processes. The latest studies in the field of brain development are reviewed, with a particular focus on the role of individual variability and the consequent heterogeneity in brain structural and functional development. This review also highlights how such heterogeneity might be utilized to inform our understanding of complex neuropsychiatric disorders and recommends the use of more dimensional approaches to study brain development.

Inter- and intra-observer variability in the assessment of atelectasis and consolidation in neonatal chest radiographs

International Nuclear Information System (INIS)

Bloomfield, F.H.; Teele, R.L.; Voss, M.; Knight, D.B.; Harding, J.E.

1999-01-01

Background. Radiology is an essential part of neonatal intensive care. Interpretation of chest radiographs frequently contributes to respiratory management of neonates, but there has been little assessment of the consistency of this interpretation. Objective. To assess the inter- and intra-observer variability for the reporting of atelectasis and/or consolidation in neonatal chest radiographs. Materials and methods. A total of 585 chest radiographs from the 220 babies ventilated in our nursery over a 2-year period were coded by two radiologists for generalised, lobar and segmental atelectasis and/or consolidation. Two months later one of the radiologists re-coded a random sample of these films (n = 117, 20 %). Agreement was assessed by the kappa statistic and by proportions of agreement for normality and abnormality. Results. The reported incidence of focal atelectasis was low (5-6 %). Focal changes of any nature were found in 21-26 % of films. Inter-observer agreement was fair to moderate (kappa = 0.25-0.44). Intra-observer agreement was mostly moderate to good (kappa = 0.38-0.66). Conclusion. The poor inter-observer agreement for the diagnosis of pulmonary parenchymal abnormalities on chest radiographs of neonates receiving intensive care suggests that abnormalities should be described rather than diagnoses given or that a list of differential diagnoses be offered. When research involves radiographic interpretation, the potential lack of consistency in reporting abnormalities must be borne in mind. (orig.)

Individual differences in the use of social information in foraging by captive great tits

NARCIS (Netherlands)

Marchetti, C.M.; Drent, P.J.

2000-01-01

We investigated individual differences in copying behaviour of captive great tits, Parus major, by analysing their response to a tutor indicating a new feeding site. We used two groups, each di seven male birds, labelled 'fast' and 'slow' explorers based on previous studies in which consistent

Individualized Anemia Management Reduces Hemoglobin Variability in Hemodialysis Patients

OpenAIRE

Gaweda, Adam E.; Aronoff, George R.; Jacobs, Alfred A.; Rai, Shesh N.; Brier, Michael E.

2013-01-01

One-size-fits-all protocol-based approaches to anemia management with erythropoiesis-stimulating agents (ESAs) may result in undesired patterns of hemoglobin variability. In this single-center, double-blind, randomized controlled trial, we tested the hypothesis that individualized dosing of ESA improves hemoglobin variability over a standard population-based approach. We enrolled 62 hemodialysis patients and followed them over a 12-month period. Patients were randomly assigned to receive ESA ...

Error-Free Text Typing Performance of an Inductive Intra-Oral Tongue Computer Interface for Severely Disabled Individuals.

Science.gov (United States)

Andreasen Struijk, Lotte N S; Bentsen, Bo; Gaihede, Michael; Lontis, Eugen R

2017-11-01

For severely paralyzed individuals, alternative computer interfaces are becoming increasingly essential for everyday life as social and vocational activities are facilitated by information technology and as the environment becomes more automatic and remotely controllable. Tongue computer interfaces have proven to be desirable by the users partly due to their high degree of aesthetic acceptability, but so far the mature systems have shown a relatively low error-free text typing efficiency. This paper evaluated the intra-oral inductive tongue computer interface (ITCI) in its intended use: Error-free text typing in a generally available text editing system, Word. Individuals with tetraplegia and able bodied individuals used the ITCI for typing using a MATLAB interface and for Word typing for 4 to 5 experimental days, and the results showed an average error-free text typing rate in Word of 11.6 correct characters/min across all participants and of 15.5 correct characters/min for participants familiar with tongue piercings. Improvements in typing rates between the sessions suggest that typing ratescan be improved further through long-term use of the ITCI.

Inter- and intra-individual differences in skin hydration and surface lipids measured with mid-infrared spectroscopy

Science.gov (United States)

Ezerskaia, A.; Pereira, S. F.; Urbach, H. P.; Varghese, B.

2016-03-01

Skin health is characterized by heterogeneous system of water and lipids in upper layers providing protection from external environment and preventing loss of vital components of the body. Skin hydration (moisture) and sebum (skin surface lipids) are considered to be important factors in skin health; a right balance between these components is an indication of healthy skin and plays a central role in protecting and preserving skin integrity. In this manuscript we present inter- and intra-individual variation in skin hydration and surface lipids measured with a home-built experimental prototype based on infrared spectroscopy. Results show good agreement with measurements performed by commercially available instruments Corneometer and Sebumeter used for skin hydration and sebum measurements respectively.

Intra-industry Affiliate Trade of Foreign Owned Companies in Poland 1993-2002

DEFF Research Database (Denmark)

Nielsen, Jørgen Ulff-Møller; Pawlik, Konrad

2004-01-01

The concept of intra-industry international exchange of goods and assets has attracted a lot of interests within the last 30 years. Concepts like intra-industry trade, intra-industry foreign direct investments, intra-industry affiliate sale, and intra-industry supply have been used in theoretical...... (exports and imports) and industry variables (wages, employment, foreign capital share, investments, sales, etc.) of foreign owned companies in the Polish manufacturing industry for the years 1993-2002, this paper, investigates for the first time intra-industry affiliate trade (IIAT), including its...... and empirical research with most emphasis laid on intra-industry trade. What has not been investigated until now is a subgroup within intra-industry trade, namely intra-industry affiliate trade which is two-way trade from foreign owned affiliates in a country. By use of a unique database containing trade...

Intra-industry Affiliate Trade of Foreign Owned Companies in Poland 1993-2002

DEFF Research Database (Denmark)

Nielsen, Jørgen Ulff-Møller; Pawlik, Konrad

The concept of intra-industry international exchange of goods and assets has attracted a lot of interests within the last 30 years. Concepts like intra-industry trade, intra-industry foreign direct investments, intra-industry affiliate sale, and intra-industry supply have been used in theoretical...... and empirical research with most emphasis laid on intra-industry trade. What has not been investigated until now is a subgroup within intra-industry trade, namely intra-industry affiliate trade, which is two-way trade from/to foreign owned affiliates in a country. By use of a unique database containing trade...... (exports and imports) and industry variables (wages, employment, foreign capital share, investments, sales, etc.) of foreign owned companies in the Polish manufacturing industry for the years 1993-2002, this paper, investigates for the first time intra-industry affiliate trade (IIAT), including its...

Direct Aggression and Generalized Anxiety in Adolescence: Heterogeneity in Development and Intra-Individual Change.

Science.gov (United States)

Meeus, Wim; Van de Schoot, Rens; Hawk, Skyler T; Hale, William W; Branje, Susan

2016-02-01

Co-occurrence of aggression and anxiety might change during adolescence, or stay stable. We studied change and stability of four types of co-occurrence regarding direct aggression and anxiety in adolescence: an anxious and non-aggressive type, an aggressive and non-anxious type, a comorbid aggressive-anxious type and a no problems type. We applied a person-centered approach to assess increases and decreases of these types, and tested various models of intra-individual change of the types: the stability, acting out and failure models. We used data from a five-wave study of 923 early-to-middle and 390 middle-to-late adolescents (48.5 % male), thereby covering the ages of 12-20. We observed accelerated development in the older cohort: adolescents tended to grow faster out of the aggressive types in middle-to-late adolescence than in early-to-middle adolescence. We observed one other group-dependent pattern of heterogeneity in development, namely "gender differentiation": gender differences in aggression and generalized anxiety became stronger over time. We found support for two perspectives on intra-individual change of the four types, namely the stability and the acting out perspective. The no problems--and to a lesser extent the anxious--type proved to be stable across time. Acting out was found in early-to-middle adolescents, males, and adolescents with poorer-quality friendships. In all three groups, there were substantial transitions from the anxious type to the aggressive type during 4 years (between 20 and 41 %). Remarkably, acting out was most prevalent in subgroups that, generally speaking, are more vulnerable for aggressive behavior, namely early-to-middle adolescents and males. We interpret acting out as the attempt of adolescents to switch from anxiety to instrumental aggression, in order to become more visible and obtain an autonomous position in the adolescent world. Acting out contributed to the explanation of accelerated development and gender

Pathogen prevalence predicts human cross-cultural variability in individualism/collectivism.

Science.gov (United States)

Fincher, Corey L; Thornhill, Randy; Murray, Damian R; Schaller, Mark

2008-06-07

Pathogenic diseases impose selection pressures on the social behaviour of host populations. In humans (Homo sapiens), many psychological phenomena appear to serve an antipathogen defence function. One broad implication is the existence of cross-cultural differences in human cognition and behaviour contingent upon the relative presence of pathogens in the local ecology. We focus specifically on one fundamental cultural variable: differences in individualistic versus collectivist values. We suggest that specific behavioural manifestations of collectivism (e.g. ethnocentrism, conformity) can inhibit the transmission of pathogens; and so we hypothesize that collectivism (compared with individualism) will more often characterize cultures in regions that have historically had higher prevalence of pathogens. Drawing on epidemiological data and the findings of worldwide cross-national surveys of individualism/collectivism, our results support this hypothesis: the regional prevalence of pathogens has a strong positive correlation with cultural indicators of collectivism and a strong negative correlation with individualism. The correlations remain significant even when controlling for potential confounding variables. These results help to explain the origin of a paradigmatic cross-cultural difference, and reveal previously undocumented consequences of pathogenic diseases on the variable nature of human societies.

Inter- and intra-individual variability in the levels of plasma homovanillic acid in schizophrenic patients.

Science.gov (United States)

Zumárraga, Mercedes; Dávila, Ricardo; González-Torres, Miguel Angel; Anguiano, Juan B; Zabalo, María José; Basterreche, Nieves; Arrúe, Aurora; Zamalloa, María Isabel; Guimón, José

2007-04-13

Changes in the levels of homovanillic acid in blood plasma (pHVA) may reflect changes which occur in the brain. In healthy individuals, this concentration of pHVA is stable over time. Over the course of one month, we studied 98 acute schizophrenic patients who had not been taking any medication but were administered neuroleptics upon hospital admission, together with 23 chronic schizophrenic patients on long-term treatment from whom medication was withdrawn. Blood samples were taken at regular intervals from each individual and the concentration of plasma homovanillic acid was measured. We found relative stable values of pHVA with an intraclass correlation coefficient of 0.363 in acute patients and 0.638 (ppHVA and the presence of pharmacological stimuli, we found a certain reproducibility in the levels of this dopamine metabolite. These findings are consistent with the idea that the dopaminergic activity is characterized by a constitutive value which would be under genetic control. The higher stability observed in chronic patients may reflect a weaker, age-related dopaminergic plasticity; conversely, it may indicate that a lack of plasticity in response to a pharmacological stimulus may be an indicator of poorer prognosis.

Intertrial Variability in the Premotor Cortex Accounts for Individual Differences in Peripersonal Space.

Science.gov (United States)

Ferri, Francesca; Costantini, Marcello; Huang, Zirui; Perrucci, Mauro Gianni; Ferretti, Antonio; Romani, Gian Luca; Northoff, Georg

2015-12-16

We live in a dynamic environment, constantly confronted with approaching objects that we may either avoid or be forced to address. A multisensory and sensorimotor interface, the peripersonal space (PPS), mediates every physical interaction between our body and the environment. Behavioral investigations show high variability in the extension of PPS across individuals, but there is a lack of evidence on the neural underpinnings of these large individual differences. Here, we used approaching auditory stimuli and fMRI to capture the individual boundary of PPS and examine its neural underpinnings. Precisely, we tested the hypothesis that intertrial variability (ITV) in brain regions coding PPS predicts individual differences of its boundary at the behavioral level. Selectively in the premotor cortex, we found that ITV, rather than trial-averaged amplitude, of BOLD responses to far rather than near dynamic stimuli predicts the individual extension of PPS. Our results provide the first empirical support for the relevance of ITV of brain responses for individual differences in human behavior. Peripersonal space (PPS) is a multisensory and sensorimotor interface mediating every physical interaction between the body and the environment. A major characteristic of the boundary of PPS in humans is the extremely high variability of its location across individuals. We show that interindividual differences in the extension of the PPS are predicted by variability of BOLD responses in the premotor cortex to far stimuli approaching our body. Our results provide the first empirical support to the relevance of variability of evoked responses for human behavior and its variance across individuals. Copyright © 2015 the authors 0270-6474/15/3516328-12$15.00/0.

Inter-individual cognitive variability in children with Asperger’s syndrome

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Maria Luz Gonzalez-Gadea

2014-07-01

Full Text Available Multiple studies have tried to establish the distinctive profile of individuals with Asperger’s syndrome (AS. However, recent reports suggest that adults with AS feature heterogeneous cognitive profiles. The present study explores inter-individual variability in children with AS through group comparison and multiple case series analysis. All participants completed an extended battery including measures of fluid and crystallized intelligence, executive functions, theory of mind, and classical neuropsychological tests. Significant group differences were found in theory of mind and other domains related to global information processing. However, the AS group showed high inter-individual variability (both sub- and supra-normal performance on most cognitive tasks. Furthermore, high fluid intelligence correlated with less general cognitive impairment, high cognitive flexibility, and speed motor processing. In light of these findings, we propose that children with AS are characterized by a distinct, uneven pattern of cognitive strengths and weaknesses.

Intra- and inter-observer variability and accuracy in the determination of linear and angular measurements in computed tomography

International Nuclear Information System (INIS)

Christiansen, E.L.; Thompson, J.R.; Kopp, S.

1986-01-01

The observer variability and accuracy of linear and angular computed tomography (CT) software measurements in the transaxial plane were investigated for the temporomandibular joint with the General Electric 8800 CT/N Scanner. A dried and measured human mandible was embedded in plastic and scanned in vitro. Sixteen observers participated in the study. The following measurements were tested: inter- and extra-condylar distances, transverse condylar dimension, condylar angulation, and the plastic base of the specimen. Three frozen cadaveric heads were similarly scanned and measured in situ. Intra- and inter-observer variabilities were lowest for the specimen base and highest for condylar angulation. Neuroradiologists had the lowest variability as a group, and the radiology residents and paramedical personell had the highest, but the differences were small. No significant difference was found between CT and macroscopic measurement of the mandible. In situ measurement by CT of condyles with structural changes in the transaxial plane was, however, subject to substantial error. It was concluded that transaxial linear measurements of the condylar processes free of significant structural changes had an error and an accuracy well within acceptable limits. The error for angular measurements was significantly greater than the error for linear measurements

The association between team-level social capital and individual-level work engagement: Differences between subtypes of social capital and the impact of intra-team agreement.

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Meng, Annette; Clausen, Thomas; Borg, Vilhelm

2018-04-01

The study explored the association between team-level social capital and individual-level work engagement. Questionnaire data were collected from six companies in the dairy industry. Seven hundred seventy-two participants divided into 65 teams were included. In confirmatory factor analyses, we found a superior model fit to a four dimensional model of social capital: bonding social capital, bridging social capital and two types of linking social capital. The results showed a positive association between all subtypes of social capital at the team level and work engagement at the individual level. However, this association only remained significant for linking social capital in relation the workplace as a whole when we adjusted for psychosocial working conditions. The level of intra-team agreement in social capital score did not moderate the association between social capital and work engagement. In conclusion, the results provide further support for previous findings suggesting a positive association between social capital and work engagement. They add to the existing knowledge by suggesting that linking social capital in relation to the workplace is the most important explanatory variable for work engagement, thus emphasizing the need to distinguish between subtypes of social capital in research and practice. © 2018 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Inter- and Intra-method Variability of VS Profiles and VS30 at ARRA-funded Sites

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Yong, A.; Boatwright, J.; Martin, A. J.

2015-12-01

The 2009 American Recovery and Reinvestment Act (ARRA) funded geophysical site characterizations at 191 seismographic stations in California and in the central and eastern United States. Shallow boreholes were considered cost- and environmentally-prohibitive, thus non-invasive methods (passive and active surface- and body-wave techniques) were used at these stations. The drawback, however, is that these techniques measure seismic properties indirectly and introduce more uncertainty than borehole methods. The principal methods applied were Array Microtremor (AM), Multi-channel Analysis of Surface Waves (MASW; Rayleigh and Love waves), Spectral Analysis of Surface Waves (SASW), Refraction Microtremor (ReMi), and P- and S-wave refraction tomography. Depending on the apparent geologic or seismic complexity of the site, field crews applied one or a combination of these methods to estimate the shear-wave velocity (VS) profile and calculate VS30, the time-averaged VS to a depth of 30 meters. We study the inter- and intra-method variability of VS and VS30 at each seismographic station where combinations of techniques were applied. For each site, we find both types of variability in VS30 remain insignificant (5-10% difference) despite substantial variability observed in the VS profiles. We also find that reliable VS profiles are best developed using a combination of techniques, e.g., surface-wave VS profiles correlated against P-wave tomography to constrain variables (Poisson's ratio and density) that are key depth-dependent parameters used in modeling VS profiles. The most reliable results are based on surface- or body-wave profiles correlated against independent observations such as material properties inferred from outcropping geology nearby. For example, mapped geology describes station CI.LJR as a hard rock site (VS30 > 760 m/s). However, decomposed rock outcrops were found nearby and support the estimated VS30 of 303 m/s derived from the MASW (Love wave) profile.

Individual and collective stock dynamics: intra-day seasonalities

International Nuclear Information System (INIS)

Allez, Romain; Bouchaud, Jean-Philippe

2011-01-01

We establish several new stylized facts concerning the intra-day seasonalities of stock dynamics. Beyond the well-known U-shaped pattern of the volatility, we find that the average correlation between stocks increases throughout the day, leading to a smaller relative dispersion between stocks. Somewhat paradoxically, the kurtosis (a measure of volatility surprises) reaches a minimum at the open of the market, when the volatility is at its peak. We confirm that the dispersion kurtosis is a markedly decreasing function of the index return. This means that during large market swings, the idiosyncratic component of the stock dynamics becomes sub-dominant. In a nutshell, the early hours of trading are dominated by idiosyncratic or sector-specific effects with little surprises, whereas the influence of the market factor increases throughout the day, and surprises become more frequent.

The renal protective effect of angiotensin receptor blockers depends on intra-individual response variation in multiple risk markers

DEFF Research Database (Denmark)

Schievink, Bauke; de Zeeuw, Dick; Parving, Hans-Henrik

2015-01-01

, haemoglobin, cholesterol and uric acid after 6 months of losartan treatment were assessed in the RENAAL database. Improvement in predictive performance of renal outcomes (ESRD or doubling serum creatinine) for each individual using ARB-induced changes in all risk markers was assessed by the relative...... integrative discrimination index (RIDI). RESULTS: SBP response showed high variability (mean -5.7 mmHg, 5(th) to 95(th) percentile -36.5 to +24.0 mmHg) between individuals. Changes in off-target parameters also showed high variability between individuals. No congruency was observed between responses...

Intra-abdominal fat area measurement using chest CT data

International Nuclear Information System (INIS)

Moriya, Hiroshi; Midorikawa, Shigeo; Hashimoto, Kouji; Ishii, Akira; Saitou, Kumi; Andou, Tomonori; Kitamura, Naoko; Sakuma, Koutarou

2007-01-01

Intra-abdominal fat obesity, which is linked with the metabolic syndrome, is usually characterized by measuring intra-abdominal fat area at the umbilical level of abdominal CT scan. In recent year, the chances of chest CT scanning are increased, as lung cancer screening survey or individual medical examination. Thus, we presented a method of measuring the areas of intra-abdominal fat and subcutaneous fat at the lower slice of chest CT scan. Fat areas found with this method were significantly correlated with those obtained at the umbilical level. (author)

Visual cues and listening effort: individual variability.

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Picou, Erin M; Ricketts, Todd A; Hornsby, Benjamin W Y

2011-10-01

To investigate the effect of visual cues on listening effort as well as whether predictive variables such as working memory capacity (WMC) and lipreading ability affect the magnitude of listening effort. Twenty participants with normal hearing were tested using a paired-associates recall task in 2 conditions (quiet and noise) and 2 presentation modalities (audio only [AO] and auditory-visual [AV]). Signal-to-noise ratios were adjusted to provide matched speech recognition across audio-only and AV noise conditions. Also measured were subjective perceptions of listening effort and 2 predictive variables: (a) lipreading ability and (b) WMC. Objective and subjective results indicated that listening effort increased in the presence of noise, but on average the addition of visual cues did not significantly affect the magnitude of listening effort. Although there was substantial individual variability, on average participants who were better lipreaders or had larger WMCs demonstrated reduced listening effort in noise in AV conditions. Overall, the results support the hypothesis that integrating auditory and visual cues requires cognitive resources in some participants. The data indicate that low lipreading ability or low WMC is associated with relatively effortful integration of auditory and visual information in noise.

Individual variation in habitat use in two stream fish assemblages

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Luisa Resende Manna

2015-12-01

Full Text Available The habitat use is an individual choice that is influenced by physical conditions such as substrate type, food resources availability and adequate depth. However, habitat use is often measured only through interspecific variability because intraspecific variability is supposed to be low. Here, the differences in habitat use by two stream fish assemblages in two different environments (Brazilian rainforest and semiarid were investigated at both interspecific and intraspecific levels. We performed 55 hours of underwater observation in a 200 meters long stretch in each stream and quantified the following habitat descriptors: (i water velocity, (ii distance from the stream bank, (iii substratum, (iv water column depth, (v aquatic cover, and (vi canopy percentage. To compare intra and interspecific variability we summarized the multivariate habitat use databases using Principal Components Analysis (PCA on Euclidean distance. An Analysis of Similarity (ANOSIM was performed to test the differences in habitat use by the two assemblages. Besides, in each fish community we did an Analysis of Variance (ANOVA to test within vs between species variability for individual position on each PCA axes. To go further than these univariate tests, the differences among the species and assemblages were tested with Permutational Multivariate Analysis of Variance (PERMANOVA. The habitat use between assemblages was significantly different (ANOSIM – R=0.14; p<0.001. PERMANOVA revealed significant differences among species in both assemblages (Rainforest - F=7.25; p<0.001; semiarid - F=4.84; p<0.001. Lower F values in the semiarid assemblage revealed a higher level of intraspecific variability for this assemblage. Our findings showed high intra and interspecific variability in both stream fish assemblages and highlight the importance of measuring individual’s differences for this feature of fish biodiversity. Additionally, the versatility described for tropical

Pelvic incidence variation among individuals: functional influence versus genetic determinism.

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Chen, Hong-Fang; Zhao, Chang-Qing

2018-03-20

Pelvic incidence has become one of the most important sagittal parameters in spinal surgery. Despite its great importance, pelvic incidence can vary from 33° to 85° in the normal population. The reasons for this great variability in pelvic incidence remain unexplored. The objective of this article is to present some possible interpretations for the great variability in pelvic incidence under both normal and pathological conditions and to further understand the determinants of pelvic incidence from the perspective of the functional requirements for bipedalism and genetic backgrounds via a literature review. We postulate that both pelvic incidence and pelvic morphology may be genetically predetermined, and a great variability in pelvic incidence may already exist even before birth. This great variability may also serve as a further reminder that the sagittal profile, bipedal locomotion mode, and genetic background of every individual are unique and specific, and clinicians should avoid making universally applying broad generalizations of pelvic incidence. Although PI is an important parameter and there are many theories behind its variability, we still do not have clear mechanistic answers.

Inter- and intra-host viral diversity in a large seasonal DENV2 outbreak.

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Camila Malta Romano

Full Text Available BACKGROUND: High genetic diversity at both inter- and intra-host level are hallmarks of RNA viruses due to the error-prone nature of their genome replication. Several groups have evaluated the extent of viral variability using different RNA virus deep sequencing methods. Although much of this effort has been dedicated to pathogens that cause chronic infections in humans, few studies investigated arthropod-borne, acute viral infections. METHODS AND PRINCIPAL FINDINGS: We deep sequenced the complete genome of ten DENV2 isolates from representative classical and severe cases sampled in a large outbreak in Brazil using two different approaches. Analysis of the consensus genomes confirmed the larger extent of the 2010 epidemic in comparison to a previous epidemic caused by the same viruses in another city two years before (genetic distance = 0.002 and 0.0008 respectively. Analysis of viral populations within the host revealed a high level of conservation. After excluding homopolymer regions of 454/Roche generated sequences, we found 10 to 44 variable sites per genome population at a frequency of >1%, resulting in very low intra-host genetic diversity. While up to 60% of all variable sites at intra-host level were non-synonymous changes, only 10% of inter-host variability resulted from non-synonymous mutations, indicative of purifying selection at the population level. CONCLUSIONS AND SIGNIFICANCE: Despite the error-prone nature of RNA-dependent RNA-polymerase, dengue viruses maintain low levels of intra-host variability.

The intra-individual reproducibility of flash-evoked potentials in a sample of children.

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Schellberg, D; Gasser, T; Köhler, W

1987-07-01

Visual evoked potentials (VEPs) to flash stimuli were recorded twice from 26 children aged 10-13 years, with an intersession interval of about 10 months. Test-retest reliability was poor for recordings taken from scalp locations overlying non-specific cortex and somewhat better for specific cortex. The size of consistency coefficients (i.e. correlations within session) showed that noise and artefacts were not the decisive factors which lower reliability. A comparison with retest correlations of broad band parameters of the EEG at rest for the same sample showed, to our surprise, smaller retest reliability for VEP parameters. Variability of the VEP in children over time seems to be a substantial as its well-known inter-individual variability.

Individualized anemia management reduces hemoglobin variability in hemodialysis patients.

Science.gov (United States)

Gaweda, Adam E; Aronoff, George R; Jacobs, Alfred A; Rai, Shesh N; Brier, Michael E

2014-01-01

One-size-fits-all protocol-based approaches to anemia management with erythropoiesis-stimulating agents (ESAs) may result in undesired patterns of hemoglobin variability. In this single-center, double-blind, randomized controlled trial, we tested the hypothesis that individualized dosing of ESA improves hemoglobin variability over a standard population-based approach. We enrolled 62 hemodialysis patients and followed them over a 12-month period. Patients were randomly assigned to receive ESA doses guided by the Smart Anemia Manager algorithm (treatment) or by a standard protocol (control). Dose recommendations, performed on a monthly basis, were validated by an expert physician anemia manager. The primary outcome was the percentage of hemoglobin concentrations between 10 and 12 g/dl over the follow-up period. A total of 258 of 356 (72.5%) hemoglobin concentrations were between 10 and 12 g/dl in the treatment group, compared with 208 of 336 (61.9%) in the control group; 42 (11.8%) hemoglobin concentrations were hemoglobin concentrations were >12 g/dl in the treatment group compared with 46 (13.4%) in the control group. The median ESA dosage per patient was 2000 IU/wk in both groups. Five participants received 6 transfusions (21 U) in the treatment group, compared with 8 participants and 13 transfusions (31 U) in the control group. These results suggest that individualized ESA dosing decreases total hemoglobin variability compared with a population protocol-based approach. As hemoglobin levels are declining in hemodialysis patients, decreasing hemoglobin variability may help reduce the risk of transfusions in this population.

Inter-individual variability of stone marten behavioral responses to a highway.

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Fernando Ascensão

Full Text Available Efforts to reduce the negative impacts of roads on wildlife may be hindered if individuals within the population vary widely in their responses to roads and mitigation strategies ignore this variability. This knowledge is particularly important for medium-sized carnivores as they are vulnerable to road mortality, while also known to use available road passages (e.g., drainage culverts for safely crossing highways. Our goal in this study was to assess whether this apparently contradictory pattern of high road-kill numbers associated with a regular use of road passages is attributable to the variation in behavioral responses toward the highway between individuals. We investigated the responses of seven radio-tracked stone martens (Martes foina to a highway by measuring their utilization distribution, response turning angles and highway crossing patterns. We compared the observed responses to simulated movement parameterized by the observed space use and movement characteristics of each individual, but naïve to the presence of the highway. Our results suggested that martens demonstrate a diversity of responses to the highway, including attraction, indifference, or avoidance. Martens also varied in their highway crossing patterns, with some crossing repeatedly at the same location (often coincident with highway passages. We suspect that the response variability derives from the individual's familiarity of the landscape, including their awareness of highway passage locations. Because of these variable yet potentially attributable responses, we support the use of exclusionary fencing to guide transient (e.g., dispersers individuals to existing passages to reduce the road-kill risk.

Small Tails Tell Tall Tales--Intra-Individual Variation in the Stable Isotope Values of Fish Fin.

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Brian Hayden

Full Text Available Fish fin is a widely used, non-lethal sample material in studies using stable isotopes to assess the ecology of fishes. However, fish fin is composed of two distinct tissues (ray and membrane which may have different stable isotope values and are not homogeneously distributed within a fin. As such, estimates of the stable isotope values of a fish may vary according to the section of fin sampled.To assess the magnitude of this variation, we analysed carbon (δ13C, nitrogen (δ15N, hydrogen (δ2H and oxygen (δ18O stable isotopes of caudal fin from juvenile, riverine stages of Atlantic salmon (Salmo salar and brown trout (Salmo trutta. Individual fins were sub-sectioned into tip, mid and base, of which a further subset were divided into ray and membrane.Isotope variation between fin sections, evident in all four elements, was primarily related to differences between ray and membrane. Base sections were13C depleted relative to tip (~1‰ with equivalent variation evident between ray and membrane. A similar trend was evident in δ2H, though the degree of variation was far greater (~10‰. Base and ray sections were 18O enriched (~2‰ relative to tip and membrane, respectively. Ray and membrane sections displayed longitudinal variation in 15N mirroring that of composite fin (~1‰, indicating that variation in15N values was likely related to ontogenetic variation.To account for the effects of intra-fin variability in stable isotope analyses we suggest that researchers sampling fish fin, in increasing priority, 1 also analyse muscle (or liver tissue from a subsample of fish to calibrate their data, or 2 standardize sampling by selecting tissue only from the extreme tip of a fin, or 3 homogenize fins prior to analysis.

Efeitos de variáveis individuais e contextuais sobre desempenho individual no trabalho Effects of individuals and contextual variables on individual performance at work

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Francisco Antonio Coelho Junior

2011-08-01

Full Text Available O presente trabalho objetivou testar empiricamente um modelo teórico multinível de predição de desempenho individual no trabalho. As variáveis antecedentes investigadas, isoladas ou em interação, corresponderam à idade, gênero, cargo, grau de escolaridade, tempo de serviço e percepção de suporte à aprendizagem, medidas no nível individual e de contexto, e satisfação no trabalho, de nível individual. A pesquisa foi realizada em uma empresa pública, do ramo de pesquisas agropecuária e atuação nacional. A amostra (N = 808 contou com funcionários distribuídos em 45 unidades centralizadas e descentralizadas da empresa pelo Brasil. A coleta de dados foi realizada à distância, via e-mail. Os resultados multiníveis corroboraram o modelo teórico de pesquisa hipotetizado e evidenciaram que a variância de desempenho foi explicada por distintos preditores de nível individual e de contexto, isoladamente ou em interação.This paper aims to empirically test a theoretical multilevel model for the prediction of individual performance at work. Antecedent variables, isolated or in interaction, were age, gender, function, scholarity, period of function and perception of learning support, in the individual and contextual levels, and satisfaction at work, an individual variable. This study was accomplished in a public corporation which deals with agricultural research in a national scope. The participants (N = 808 were distribute in 45 central and noncentral units for the Brazil. Data collection was done online, by e-mail. The multilevel results confirm the hypothetic theoretical model and make evident that the performance's variance were predicted by different individuals and context variables, isolated or in interaction.

Predictors of "occult" intra-abdominal injuries in blunt trauma patients.

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Parreira, José Gustavo; Malpaga, Juliano Mangini Dias; Olliari, Camilla Bilac; Perlingeiro, Jacqueline A G; Soldá, Silvia C; Assef, José Cesar

2015-01-01

to assess predictors of intra-abdominal injuries in blunt trauma patients admitted without abdominal pain or abnormalities on the abdomen physical examination. We conducted a retrospective analysis of trauma registry data, including adult blunt trauma patients admitted from 2008 to 2010 who sustained no abdominal pain or abnormalities on physical examination of the abdomen at admission and were submitted to computed tomography of the abdomen and/or exploratory laparotomy. Patients were assigned into: Group 1 (with intra-abdominal injuries) or Group 2 (without intra-abdominal injuries). Variables were compared between groups to identify those significantly associated with the presence of intra-abdominal injuries, adopting ptrauma mechanism (ptrauma mechanism (p=0.008 - OR 2.85; 95%CI 1.13-6.22) and abnormal neurological physical exam at admission (p=0.015 - OR 0.44; 95%CI 0.22-0.85). Intra-abdominal injuries were predominantly associated with trauma mechanism and presence of chest injuries.

Effects of climate variables on intra-annual stem radial increment in Pinus cembra (L.) along the alpine treeline ecotone.

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Gruber, Andreas; Zimmermann, Jolanda; Wieser, Gerhard; Oberhuber, Walter

2009-08-01

Within the alpine treeline ecotone tree growth is increasingly restricted by extreme climate conditions. Although intra-annual stem growth recorded by dendrometers can be linked to climate, stem diameter increments in slow-growing subalpine trees are masked by changes in tree water status.We tested the hypothesis that intra-annual radial stem growth in Pinus cembra is influenced by different climate variables along the treeline ecotone in the Austrian Alps. Dendrometer traces were compared with dynamics of xylem cell development to date onset of cambial activity and radial stem growth in spring.Daily fluctuations in stem radius reflected changes in tree water status throughout the treeline ecotone. Extracted daily radial increments were significantly correlated with air temperature at the timberline and treeline only, where budburst, cambial activity and enlargement of first tracheids also occurred quite similarly. A close relationship was detected between radial increment and number of enlarging tracheids throughout the treeline ecotone.We conclude that (i) the relationship between climate and radial stem growth within the treeline ecotone is dependent on a close coupling to atmospheric climate conditions and (ii) initiation of cambial activity and radial growth in spring can be distinguished from stem re-hydration by histological analysis.

Intra-night Optical Variability Monitoring of Fermi Blazars: First Results from 1.3 m J. C. Bhattacharya Telescope

Energy Technology Data Exchange (ETDEWEB)

Paliya, Vaidehi S.; Ajello, M.; Kaur, A. [Department of Physics and Astronomy, Clemson University, Kinard Lab of Physics, Clemson, SC 29634-0978 (United States); Stalin, C. S., E-mail: vpaliya@g.clemson.edu [Indian Institute of Astrophysics, Block II, Koramangala, Bangalore-560034 (India)

2017-07-20

We report the first results obtained from our campaign to characterize the intra-night-optical variability (INOV) properties of Fermi detected blazars, using the observations from the recently commissioned 1.3 m J. C. Bhattacharya telescope (JCBT). During the first run, we were able to observe 17 blazars in the Bessel R filter for ∼137 hr. Using C- and scaled F -statistics, we quantify the extent of INOV and derive the duty cycle (DC), which is the fraction of time during which a source exhibits a substantial flux variability. We find a high DC of 40% for BL Lac objects and the flat spectrum radio quasars are relatively less variable (DC ∼ 15%). However, when estimated for blazars sub-classes, a high DC of ∼59% is found in low synchrotron peaked (LSP) blazars, whereas, intermediate and high synchrotron peaked objects have a low DC of ∼11% and 13%, respectively. We find evidence of the association of the high amplitude INOV with the γ -ray flaring state. We also notice a high polarization during the elevated INOV states (for the sources that have polarimetric data available), thus supporting the jet based origin of the observed variability. We plan to enlarge the sample and utilize the time availability from the small telescopes, such as 1.3 m JCBT, to strengthen/verify the results obtained in this work and those existing in the literature.

Analyzing Variability in Landscape Nutrient Loading Using Spatially-Explicit Maps in the Great Lakes Basin

Science.gov (United States)

Hamlin, Q. F.; Kendall, A. D.; Martin, S. L.; Whitenack, H. D.; Roush, J. A.; Hannah, B. A.; Hyndman, D. W.

2017-12-01

Excessive loading of nitrogen and phosphorous to the landscape has caused biologically and economically damaging eutrophication and harmful algal blooms in the Great Lakes Basin (GLB) and across the world. We mapped source-specific loads of nitrogen and phosphorous to the landscape using broadly available data across the GLB. SENSMap (Spatially Explicit Nutrient Source Map) is a 30m resolution snapshot of nutrient loads ca. 2010. We use these maps to study variable nutrient loading and provide this information to watershed managers through NOAA's GLB Tipping Points Planner. SENSMap individually maps nutrient point sources and six non-point sources: 1) atmospheric deposition, 2) septic tanks, 3) non-agricultural chemical fertilizer, 4) agricultural chemical fertilizer, 5) manure, and 6) nitrogen fixation from legumes. To model source-specific loads at high resolution, SENSMap synthesizes a wide range of remotely sensed, surveyed, and tabular data. Using these spatially explicit nutrient loading maps, we can better calibrate local land use-based water quality models and provide insight to watershed managers on how to focus nutrient reduction strategies. Here we examine differences in dominant nutrient sources across the GLB, and how those sources vary by land use. SENSMap's high resolution, source-specific approach offers a different lens to understand nutrient loading than traditional semi-distributed or land use based models.

Characterisation of the main drivers of intra- and inter- breed variability in the plasma metabolome of dogs.

Science.gov (United States)

Lloyd, Amanda J; Beckmann, Manfred; Tailliart, Kathleen; Brown, Wendy Y; Draper, John; Allaway, David

Dog breeds are a consequence of artificial selection for specific attributes. These closed genetic populations have metabolic and physiological characteristics that may be revealed by metabolomic analysis. To identify and characterise the drivers of metabolic differences in the fasted plasma metabolome and then determine metabolites differentiating breeds. Fasted plasma samples were collected from dogs maintained under two environmental conditions (controlled and client-owned at home). The former (n = 33) consisted of three breeds (Labrador Retriever, Cocker Spaniel and Miniature Schnauzer) fed a single diet batch, the latter (n = 96), client-owned dogs consisted of 9 breeds (Beagle, Chihuahua, Cocker Spaniel, Dachshund, Golden Retriever, Greyhound, German Shepherd, Labrador Retriever and Maltese) consuming various diets under differing feeding regimens. Triplicate samples were taken from Beagle (n = 10) and Labrador Retriever (n = 9) over 3 months. Non-targeted metabolite fingerprinting was performed using flow infusion electrospray-ionization mass spectrometry which was coupled with multivariate data analysis. Metadata factors including age, gender, sexual status, weight, diet and breed were investigated. Breed differences were identified in the plasma metabolome of dogs housed in a controlled environment. Triplicate samples from two breeds identified intra-individual variability, yet breed separation was still observed. The main drivers of variance in dogs maintained in the home environment were associated with breed and gender. Furthermore, metabolite signals were identified that discriminated between Labrador Retriever and Cocker Spaniels in both environments. Metabolite fingerprinting of plasma samples can be used to investigate breed differences in client-owned dogs, despite added variance of diet, sexual status and environment.

Establishing an air pollution monitoring network for intra-urban population exposure assessment : a location-allocation approach

Energy Technology Data Exchange (ETDEWEB)

Kanaroglou, P.S. [McMaster Univ., Hamilton, ON (Canada). School of Geography and Geology; Jerrett, M.; Beckerman, B.; Arain, M.A. [McMaster Univ., Hamilton, ON (Canada). School of Geography and Geology]|[McMaster Univ., Hamilton, ON (Canada). McMaster Inst. of Environment and Health; Morrison, J. [Carleton Univ., Ottawa, ON (Canada). School of Computer Science; Gilbert, N.L. [Health Canada, Ottawa, ON (Canada). Air Health Effects Div; Brook, J.R. [Meteorological Service of Canada, Toronto, ON (Canada)

2004-10-01

A study was conducted to assess the relation between traffic-generated air pollution and health reactions ranging from childhood asthma to mortality from lung cancer. In particular, it developed a formal method of optimally locating a dense network of air pollution monitoring stations in order to derive an exposure assessment model based on the data obtained from the monitoring stations and related land use, population and biophysical information. The method for determining the locations of 100 nitrogen dioxide monitors in Toronto, Ontario focused on land use, transportation infrastructure and the distribution of at-risk populations. The exposure assessment produced reasonable estimates at the intra-urban scale. This method for locating air pollution monitors effectively maximizes sampling coverage in relation to important socio-demographic characteristics and likely pollution variability. The location-allocation approach integrates many variables into the demand surface to reconfigure a monitoring network and is especially useful for measuring traffic pollutants with fine-scale spatial variability. The method also shows great promise for improving the assessment of exposure to ambient air pollution in epidemiologic studies. 19 refs., 3 tabs., 4 figs.

Long-term and within-day variability of working memory performance and EEG in individuals.

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Gevins, Alan; McEvoy, Linda K; Smith, Michael E; Chan, Cynthia S; Sam-Vargas, Lita; Baum, Cliff; Ilan, Aaron B

2012-07-01

Assess individual-subject long-term and within-day variability of a combined behavioral and EEG test of working memory. EEGs were recorded from 16 adults performing n-back working memory tasks, with 10 tested in morning and afternoon sessions over several years. Participants were also tested after ingesting non-prescription medications or recreational substances. Performance and EEG measures were analyzed to derive an Overall score and three constituent sub-scores characterizing changes in performance, cortical activation, and alertness from each individual's baseline. Long-term and within-day variability were determined for each score; medication effects were assessed by reference to each individual's normal day-to-day variability. Over the several year period, the mean Overall score and sub-scores were approximately zero with standard deviations less than one. Overall scores were lower and their variability higher in afternoon relative to morning sessions. At the group level, alcohol, diphenhydramine and marijuana produced significant effects, but there were large individual differences. Objective working memory measures incorporating performance and EEG are stable over time and sensitive at the level of individual subjects to interventions that affect neurocognitive function. With further research these measures may be suitable for use in individualized medical care by providing a sensitive assessment of incipient illness and response to treatment. Published by Elsevier Ireland Ltd.

Inter-individual Differences in Heart Rate Variability Are Associated with Inter-individual Differences in Empathy and Alexithymia

Directory of Open Access Journals (Sweden)

Alexander Lischke

2018-02-01

Full Text Available In the present study, we investigated whether inter-individual differences in vagally mediated heart rate variability (vmHRV would be associated with inter-individual differences in empathy and alexithymia. To this end, we determined resting state HF-HRV in 90 individuals that also completed questionnaires assessing inter-individual differences in empathy and alexithymia. Our categorical and dimensional analyses revealed that inter-individual differences in HF-HRV were differently associated with inter-individual differences in empathy and alexithymia. We found that individuals with high HF-HRV reported more empathy and less alexithymia than individuals with low HF-HRV. Moreover, we even found that an increase in HF-HRV was associated with an increase in empathy and a decrease in alexithymia across all participants. Taken together, these findings indicate that individuals with high HF-HRV are more empathetic and less alexithymic than individuals with low HF-HRV. These differences in empathy and alexithymia may explain why individuals with high HF-HRV are more successful in sharing and understanding the mental and emotional states of others than individuals with low HF-HRV.

Estimating the reliability of glycemic index values and potential sources of methodological and biological variability.

Science.gov (United States)

Matthan, Nirupa R; Ausman, Lynne M; Meng, Huicui; Tighiouart, Hocine; Lichtenstein, Alice H

2016-10-01

The utility of glycemic index (GI) values for chronic disease risk management remains controversial. Although absolute GI value determinations for individual foods have been shown to vary significantly in individuals with diabetes, there is a dearth of data on the reliability of GI value determinations and potential sources of variability among healthy adults. We examined the intra- and inter-individual variability in glycemic response to a single food challenge and methodologic and biological factors that potentially mediate this response. The GI value for white bread was determined by using standardized methodology in 63 volunteers free from chronic disease and recruited to differ by sex, age (18-85 y), and body mass index [BMI (in kg/m 2 ): 20-35]. Volunteers randomly underwent 3 sets of food challenges involving glucose (reference) and white bread (test food), both providing 50 g available carbohydrates. Serum glucose and insulin were monitored for 5 h postingestion, and GI values were calculated by using different area under the curve (AUC) methods. Biochemical variables were measured by using standard assays and body composition by dual-energy X-ray absorptiometry. The mean ± SD GI value for white bread was 62 ± 15 when calculated by using the recommended method. Mean intra- and interindividual CVs were 20% and 25%, respectively. Increasing sample size, replication of reference and test foods, and length of blood sampling, as well as AUC calculation method, did not improve the CVs. Among the biological factors assessed, insulin index and glycated hemoglobin values explained 15% and 16% of the variability in mean GI value for white bread, respectively. These data indicate that there is substantial variability in individual responses to GI value determinations, demonstrating that it is unlikely to be a good approach to guiding food choices. Additionally, even in healthy individuals, glycemic status significantly contributes to the variability in GI value

Effect of Intra Vitreal Injection of Bevacizumab on Intra-Occular Pressure

International Nuclear Information System (INIS)

Jaffar, S.; Tayyab, A.; Matin, Z. I.; Masrur, A.; Naqaish, R.

2016-01-01

Background: Bevacizumab has been in use as a therapeutic agent for macular oedema for several years. While its efficacy has been well documented, its use has been shown to cause a transient rise in the intra-ocular pressure. The aim of this study was to evaluate the long term effect of intra-vitreal injection of Bevacizumab on Intra-ocular pressure. Methods: One hundred eyes (n=100) of one hundred patients, requiring intra-vitreal injection of Bevacizumab for diabetic macular oedema were recruited from Shifa Foundation Community Health Centre (SFCHC) between January and December 2014. Patients of glaucoma, ocular hyper-tension, known allergy to Bevacizumab or had injections of Bevacizumab prior to the study were excluded. Intra-ocular pressure was measured using a Goldmann applanation tonometer, prior to, and at six and twelve months after the injection. The pre- and post- injection Intra-ocular pressure was entered into the database. Test of significance was applied to investigate whether there was a significant change in intra-ocular pressure after the injection. Results: The mean age of the patient was 56.97 years (±14.97). The mean intra-ocular pressure was 13.86 (±3.16) mmHg before injection, while post-injection mean Intra-Ocular pressure was 14.21 (±3.12) mmHg and 13.79 (±3.07) at six and twelve months respectively. Between baseline and six months there was a statistically significant difference in intra-ocular pressure (p=0.03), while no significant difference existed in the intra-ocular pressure between baseline and twelve months (p=0.92). Conclusion: Intra-vitreal injection of Bevacizumab is associated with a statically significant rise in intra-ocular pressure at six months, while no significant difference was seen at twelve months compared to baseline. (author)

Nonalcoholic steatohepatitis in precision medicine: Unraveling the factors that contribute to individual variability.

Science.gov (United States)

Clarke, John D; Cherrington, Nathan J

2015-07-01

There are numerous factors in individual variability that make the development and implementation of precision medicine a challenge in the clinic. One of the main goals of precision medicine is to identify the correct dose for each individual in order to maximize therapeutic effect and minimize the occurrence of adverse drug reactions. Many promising advances have been made in identifying and understanding how factors such as genetic polymorphisms can influence drug pharmacokinetics (PK) and contribute to variable drug response (VDR), but it is clear that there remain many unidentified variables. Underlying liver diseases such as nonalcoholic steatohepatitis (NASH) alter absorption, distribution, metabolism, and excretion (ADME) processes and must be considered in the implementation of precision medicine. There is still a profound need for clinical investigation into how NASH-associated changes in ADME mediators, such as metabolism enzymes and transporters, affect the pharmacokinetics of individual drugs known to rely on these pathways for elimination. This review summarizes the key PK factors in individual variability and VDR and highlights NASH as an essential underlying factor that must be considered as the development of precision medicine advances. A multifactorial approach to precision medicine that considers the combination of two or more risk factors (e.g. genetics and NASH) will be required in our effort to provide a new era of benefit for patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Predictors of "occult" intra-abdominal injuries in blunt trauma patients

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José Gustavo Parreira

Full Text Available Objective: to assess predictors of intra-abdominal injuries in blunt trauma patients admitted without abdominal pain or abnormalities on the abdomen physical examination. Methods: We conducted a retrospective analysis of trauma registry data, including adult blunt trauma patients admitted from 2008 to 2010 who sustained no abdominal pain or abnormalities on physical examination of the abdomen at admission and were submitted to computed tomography of the abdomen and/or exploratory laparotomy. Patients were assigned into: Group 1 (with intra-abdominal injuries or Group 2 (without intra-abdominal injuries. Variables were compared between groups to identify those significantly associated with the presence of intra-abdominal injuries, adopting p<0.05 as significant. Subsequently, the variables with p<0.20 on bivariate analysis were selected to create a logistic regression model using the forward stepwise method. Results: A total of 268 cases met the inclusion criteria. Patients in Group I were characterized as having significantly (p<0.05 lower mean AIS score for the head segment (1.0±1.4 vs. 1.8±1.9, as well as higher mean AIS thorax score (1.6±1.7 vs. 0.9±1.5 and ISS (25.7±14.5 vs. 17,1±13,1. The rate of abdominal injuries was significantly higher in run-over pedestrians (37.3% and in motorcyclists (36.0% (p<0.001. The resultant logistic regression model provided 73.5% accuracy for identifying abdominal injuries. The variables included were: motorcyclist accident as trauma mechanism (p<0.001 - OR 5.51; 95%CI 2.40-12.64, presence of rib fractures (p<0.003 - OR 3.00; 95%CI 1.47-6.14, run-over pedestrian as trauma mechanism (p=0.008 - OR 2.85; 95%CI 1.13-6.22 and abnormal neurological physical exam at admission (p=0.015 - OR 0.44; 95%CI 0.22-0.85. Conclusion Intra-abdominal injuries were predominantly associated with trauma mechanism and presence of chest injuries.

Noise Originating from Intra-pixel Structure and Satellite Attitude Jitter on COROT

DEFF Research Database (Denmark)

Karoff, Christoffer; Arentoft, Torben; Kjeldsen, Hans

2006-01-01

We present a study on noise in space-based photometry originating from sensitivity variations within individual pixels, known as intra-pixel variations, and satellite attitude jitter. We have measured the intra-pixel structure on an e2v 47-20 CCD and made simulations of the effects these structur...

Days on radiosensitivity: individual variability and predictive tests

International Nuclear Information System (INIS)

2008-01-01

The radiosensitivity is a part of usual clinical observations. It is already included in the therapy protocols. however, some questions stay on its individual variability and on the difficulty to evaluate it. The point will be stocked on its origin and its usefulness in predictive medicine. Through examples on the use of predictive tests and ethical and legal questions that they raise, concrete cases will be presented by specialists such radio biologists, geneticists, immunologists, jurists and occupational physicians. (N.C.)

Continuous measurement of intra-oral pH and temperature: development, validation of an appliance and a pilot study.

Science.gov (United States)

Choi, J E; Loke, C; Waddell, J N; Lyons, K M; Kieser, J A; Farella, M

2015-08-01

To describe a novel approach for continuous measurement of intra-oral pH and temperature in individuals carrying out normal daily activities over 24 h. We designed, validated and constructed a custom-made appliance fitted with a pH probe and a thermocouple. Six subjects wore the appliance over a 24-h period for two non-consecutive days, while the intra-oral pH and temperature were measured continuously and recorded. Intra-oral pH and temperature were very similar across different recording days, the difference being not statistically significant (P ≥ 0.14). There was a noticeable difference in the pattern of variation of pH between day and night. During the day, the mean pH was 7.3 (±0.4) and dropped markedly only after consumption of acidic food and drinks. The intra-oral pH decreased slowly during sleep with an average pH of 6.6 (±0.4) being recorded. The difference between day and night was statistically significant (P = 0.002). The mean intra-oral temperature was 33.9 °C (±0.9) during daytime and 35·9 °C (±0·5) during sleep (P = 0.013) with minor fluctuations occurring over 24 h. The continuous and simultaneous intra-oral pH and temperature measurement system described in this report is reliable, easy to construct, able to measure variables over a sustained period and may serve as a future diagnostic tool in a number of applications. © 2015 John Wiley & Sons Ltd.

Life Satisfaction among Mothers of Individuals with Prader-Willi Syndrome

Science.gov (United States)

Shivers, Carolyn M.; Leonczyk, Caroline L.; Dykens, Elisabeth M.

2016-01-01

Mothers of individuals with Prader-Willi syndrome (PWS) often experience numerous stressors, even when compared to mothers of children with other intellectual and developmental disabilities. Despite this, these mothers show great variability in self-reported life satisfaction. Using data from a longitudinal study of individuals with PWS and their…

Individually variable energy management during egg production is repeatable across breeding attempts.

Science.gov (United States)

Williams, Tony D; Vézina, François; Speakman, John R

2009-04-01

It is axiomatic that whole-animal metabolism, measured for example as daily energy expenditure (DEE), plays a central role in determining reproductive success and survival (fitness) in all organisms. Nevertheless, strong evidence for consistent systematic relationships between DEE and either individual traits (age, sex, body size), environmental factors (e.g. food availability, temperature) or 'fitness' traits (e.g. number of offspring, survival) remains far from compelling in birds and mammals. Recently, we suggested that female birds might utilise complex, individually variable energy management strategies to meet the metabolic demands of reproduction, generating a wide spectrum of effects on reproductive DEE, from overcompensation (net decrease in DEE) to additive effects (net increase in DEE). Here we show that this individually variable adjustment or 'plasticity' in energy expenditure associated with egg production is repeatable among individuals between successive breeding attempts in female zebra finches (Taeniopygia guttata). Our study highlights the importance (a) of measuring 'plasticity' or change associated with transitions of physiological state (e.g. non-breeding to breeding) based on multiple measurements of the same individual, and (b) of extending consideration of how selection might drive the evolution of phenotypic plasticity per se to include physiological and metabolic traits.

Quantifying the Effectiveness of Dose Individualization by Simulation for a Drug With Moderate Pharmacokinetic Variability.

Science.gov (United States)

Liefaard, Lia; Chen, Chao

2015-10-01

Dose individualization can reduce variability in exposure. The objective of this work was to quantify, through pharmacokinetic (PK) simulation, the potential for reducing the variability in exposure by dose individualization for a drug with moderate PK variability between subjects and between occasions within a subject, and a narrow therapeutic window. Using a population PK model that includes between-subject and between-occasion variability for apparent clearance, individual PK profiles in a trial of 300 subjects after a test dose were simulated. From the simulated data, datasets were created mimicking various sampling regimens (from single predose sample to full profile samples over 12 hours) on 1 or more occasions (1, 2, 3, 5, or 10 visits). Using these datasets, individual apparent clearance values were estimated, which were then used to calculate an individualized dose for a predefined target area under the concentration-time curve (AUC), based on the available formulation strengths. The proportion of people whose mean AUC was within a predefined therapeutic AUC range was calculated for the test (before) and the individualized dose (after), and compared between the different sampling scenarios. The maximum increase in proportion of subjects with an AUC within the range was 20%. To achieve this benefit, PK samples over 4 hours from 100 dosing occasions were required. As a result of the dose adjustment, the AUC of 7.3% of the subjects moved from inside the therapeutic range to outside of the range. This work shows how modeling and simulation can help assess the benefit and risk of dose individualization for a compound with variability between subjects and between occasions. The framework can be applied to similar situations with a defined set of conditions (eg, therapeutic window, tablet strengths, and PK and/or pharmacodynamic sampling scheme) to inform dose change and to assess the utility of dose individualization against certain success criteria.

Variability in prostate and seminal vesicle delineations defined on magnetic resonance images, a multi-observer, -center and -sequence study

DEFF Research Database (Denmark)

Nyholm, Tufve; Jonsson, Joakim; Söderström, Karin

2013-01-01

and approximately equal for the prostate and seminal vesicles. Large differences in variability were observed for individual patients, and also for individual imaging sequences used at the different centers. There was however no indication of decreased variability with higher field strength. CONCLUSION: The overall......BACKGROUND: The use of magnetic resonance (MR) imaging as a part of preparation for radiotherapy is increasing. For delineation of the prostate several publications have shown decreased delineation variability using MR compared to computed tomography (CT). The purpose of the present work....... Two physicians from each center delineated the prostate and the seminal vesicles on each of the 25 image sets. The variability between the delineations was analyzed with respect to overall, intra- and inter-physician variability, and dependence between variability and origin of the MR images, i...

Introducing a true internal standard for the Comet assay to minimize intra- and inter-experiment variability in measures of DNA damage and repair

Science.gov (United States)

Zainol, Murizal; Stoute, Julia; Almeida, Gabriela M.; Rapp, Alexander; Bowman, Karen J.; Jones, George D. D.

2009-01-01

The Comet assay (CA) is a sensitive/simple measure of genotoxicity. However, many features of CA contribute variability. To minimize these, we have introduced internal standard materials consisting of ‘reference’ cells which have their DNA substituted with BrdU. Using a fluorescent anti-BrdU antibody, plus an additional barrier filter, comets derived from these cells could be readily distinguished from the ‘test’-cell comets, present in the same gel. In experiments to evaluate the reference cell comets as external and internal standards, the reference and test cells were present in separate gels on the same slide or mixed together in the same gel, respectively, before their co-exposure to X-irradiation. Using the reference cell comets as internal standards led to substantial reductions in the coefficient of variation (CoV) for intra- and inter-experimental measures of comet formation and DNA damage repair; only minor reductions in CoV were noted when the reference and test cell comets were in separate gels. These studies indicate that differences between individual gels appreciably contribute to CA variation. Further studies using the reference cells as internal standards allowed greater significance to be obtained between groups of replicate samples. Ultimately, we anticipate that development will deliver robust quality assurance materials for CA. PMID:19828597

Inter- and intra-observer variability of time-lapse annotations

DEFF Research Database (Denmark)

Sundvall, Linda; Ingerslev, Hans Jakob; Breth Knudsen, Ulla

2013-01-01

. This provides the basis for further investigation of embryo assessment and selection by time-lapse imaging in prospective trials. Study funding/competing interest(s): Research at the Fertility Clinic was funded by an unrestricted grant from Ferring and MSD. The authors have no competing interests to declare.......Study question: How consistent is the time-lapse annotation of dynamic and static morphologic parameters of embryo development, within and between observers? Summary answer: The assessment of dynamic parameters is characterized by almost perfect agreement within and between observers. What is known...... already: The commonly employed method used to assess embryos in IVF treatments is based on static evaluation of morphology in a microscope, but this is limited by substantial intra- and inter-observer variation. Time-lapse imaging has been proposed as a method to refine embryo selection by adding new...

Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

DEFF Research Database (Denmark)

Antonsen, Lisbeth; Thayssen, Per; Junker, Anders

2015-01-01

to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). METHODS...... in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. RESULTS: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1%±1.4% and 0.5%±3.2%. Interobserver variability also proved...... (CI): 0.88-0.93, pstented coronary segments, and for qualitative assessment of strut coverage....

Intra-tumor heterogeneity in head and neck cancer and its clinical implications

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Edmund A. Mroz

2016-06-01

Full Text Available The presence of heritable differences among cancer cells within a tumor, called intra-tumor genetic heterogeneity, has long been suspected of playing a role in poor responses to therapy. Research over the past decade has documented the existence of such heterogeneity within tumors of individual patients and documented its potential clinical significance. The research methods for identifying this heterogeneity were not, however, readily adaptable to widespread clinical application. After a brief review of this background, we describe the development of a measure of intra-tumor genetic heterogeneity, based on whole-exome sequencing of individual tumor samples, that could be applied to biopsy specimens in a clinical setting. This measure has now been used in head and neck squamous cell carcinoma (HNSCC to document, for the first time, a relation of high intra-tumor genetic heterogeneity to shorter overall survival in a large, multi-institutional study. The implications of heterogeneity for research and clinical care thus now need to be addressed. Keywords: Head and neck squamous cell carcinoma, Intra-tumor genetic heterogeneity, Next-generation sequencing, Targeted therapy

Handheld mechanical nociceptive threshold testing in dairy cows - intra-individual variation, inter-observer agreement and variation over time.

Science.gov (United States)

Raundal, Peter M; Andersen, Pia H; Toft, Nils; Forkman, Björn; Munksgaard, Lene; Herskin, Mette S

2014-11-01

To examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed. Prospective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time. One hundred and fifteen healthy, loose-housed Danish Holstein cattle. We evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0-10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0-1000 gf). Each cow received 5-6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant. The CVs did not differ [range 0.34-0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01). All methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia. © 2014 The Authors Veterinary Anaesthesia and Analgesia published by John Wiley & Sons Ltd on behalf of Association of Veterinary Anaesthetists and the

Appropriateness of Intra-Operative Blood Transfusion In Children at ...

African Journals Online (AJOL)

Background: The decision to transfuse intra-operatively is based on preoperative haemoglobin (Hb), estimated blood loss and physiological variables. The visual estimate of blood loss is notoriously unreliable especially with small volumes of blood losses in children. Objectives :We sought therefore to determine the ...

Can the theory of planned behaviour predict the physical activity behaviour of individuals?

Science.gov (United States)

Hobbs, Nicola; Dixon, Diane; Johnston, Marie; Howie, Kate

2013-01-01

The theory of planned behaviour (TPB) can identify cognitions that predict differences in behaviour between individuals. However, it is not clear whether the TPB can predict the behaviour of an individual person. This study employs a series of n-of-1 studies and time series analyses to examine the ability of the TPB to predict physical activity (PA) behaviours of six individuals. Six n-of-1 studies were conducted, in which TPB cognitions and up to three PA behaviours (walking, gym workout and a personally defined PA) were measured twice daily for six weeks. Walking was measured by pedometer step count, gym attendance by self-report with objective validation of gym entry and the personally defined PA behaviour by self-report. Intra-individual variability in TPB cognitions and PA behaviour was observed in all participants. The TPB showed variable predictive utility within individuals and across behaviours. The TPB predicted at least one PA behaviour for five participants but had no predictive utility for one participant. Thus, n-of-1 designs and time series analyses can be used to test theory in an individual.

Intra-Industry Affiliate Trade of Foreign-Owned Companies in Transition Economies:

DEFF Research Database (Denmark)

Nielsen, Jørgen Ulff-Møller; Pawlik, Konrad

2008-01-01

Using a database containing trade and industry variables of foreign-owned companies in the Polish manufacturing industry for the years 1993-2002, we investigate the relationship between the organizational structure of multinational enterprises (MNE) in Poland and the intra-industry trade of their...... become a more important mode of organization for multinational enterprises as Poland has evolved into a relatively stable economic environment where MNEs feel comfortable basing their regional operations.......Using a database containing trade and industry variables of foreign-owned companies in the Polish manufacturing industry for the years 1993-2002, we investigate the relationship between the organizational structure of multinational enterprises (MNE) in Poland and the intra-industry trade...... of their affiliates (IIAT). We find labour intensity; scale economies and absorptive capacity of affiliates are the main explanatory variables for IIAT. Given the overall rise in export and import intensities of foreign affiliates over the period of investigation, our findings suggest that export-platform FDI has...

Moderate intra-group bias maximizes cooperation on interdependent populations.

Directory of Open Access Journals (Sweden)

Changbing Tang

Full Text Available Evolutionary game theory on spatial structures has received increasing attention during the past decades. However, the majority of these achievements focuses on single and static population structures, which is not fully consistent with the fact that real structures are composed of many interactive groups. These groups are interdependent on each other and present dynamical features, in which individuals mimic the strategy of neighbors and switch their partnerships continually. It is however unclear how the dynamical and interdependent interactions among groups affect the evolution of collective behaviors. In this work, we employ the prisoner's dilemma game to investigate how the dynamics of structure influences cooperation on interdependent populations, where populations are represented by group structures. It is found that the more robust the links between cooperators (or the more fragile the links between cooperators and defectors, the more prevalent of cooperation. Furthermore, theoretical analysis shows that the intra-group bias can favor cooperation, which is only possible when individuals are likely to attach neighbors within the same group. Yet, interestingly, cooperation can be even inhibited for large intra-group bias, allowing the moderate intra-group bias maximizes the cooperation level.

Hazard personality profiles and individual differences

International Nuclear Information System (INIS)

Barnett, J.; Breakwell, G.M.

1998-01-01

Full text of publication follows: the dominance of the 'psychometric paradigm' and the consequent emphasis on identifying the qualities related to a hazard's perceived risk has resulted in little attention being given to individual variations in the acceptance of such 'personality profiles' of hazards. Attempts to locate sources of variability have largely focused on social, cultural and institutional factors (Turner and Wynne, 1992; Sjoeberg, 1995). Less attention has been paid to the role of intra-individual differences (Myers, Henderson-King, and Henderson-King, 1997). To address this, a questionnaire study (n = 172) explored the relationships between anxiety, experience and risk perceptions in relation to 16 risk activities. Different patterns of relationships for voluntary and involuntary activities were expected. Measures of experience included assessments of impact and outcome valence as well as frequency. Proclivity for, and likelihood of, future risk experiences were also assessed. The results revealed a number of relationships between individual difference variables and risk perceptions relating to the voluntariness of the activities. For involuntary risk activities, there were associations between the experience variables and risk ratings, e.g. previous experience of positive outcomes of involuntary risk activities is associated with perceptions of them affecting few people, with not being fatal and with known risk levels. This would suggest that taking into account people's previous experience of risks is likely to affect reactions to, and mediate the effectiveness of risk communications relating to involuntary risk activities. In contrast for voluntary activities it is the two 'future' oriented variables that are associated with risk perceptions. The relationship between anxiety and risk perceptions also varied in relation to the voluntariness of risk activities. The importance of incorporating a consideration of individual differences within

Longwave thermal infrared spectral variability in individual rocks

Energy Technology Data Exchange (ETDEWEB)

Balick, Lee K [Los Alamos National Laboratory; Gillespie, Alan [UN. WASHINGTON; French, Andrew [USDA-ARS; Danilina, Iryna [UN. WASHINGTON

2008-01-01

A hyperspectral imaging spectrometer measuring in the longwave thermal infrared (7.6-11.6 {micro}m) with a spatial resolution less than 4 mm was used in the field to observe the variability of emissivity spectra within individual rocks. The rocks were obtained commercially, were on the order of 20 cm in size and were selected to have distinct spectral features: they include alabaster (gypsum), soapstone (steatite with talc), obsidian (volcanic glass), norite (plagioclase and orthopyroxene), and 'jasper' (silica with iron oxides). The advantages of using an imaging spectrometer to spectrally characterize these rocks are apparent. Large spectral variations were observed within individual rocks that may be attributed to roughness, surface geometry, and compositional variation. Non-imaging spectrometers would normally miss these variations as would small samples used in laboratory measurements, spatially averaged spectra can miss the optimum spectra for identification materials and spatially localized components of the rock can be obscured.

Functional connectivity patterns reflect individual differences in conflict adaptation.

Science.gov (United States)

Wang, Xiangpeng; Wang, Ting; Chen, Zhencai; Hitchman, Glenn; Liu, Yijun; Chen, Antao

2015-04-01

Individuals differ in the ability to utilize previous conflict information to optimize current conflict resolution, which is termed the conflict adaptation effect. Previous studies have linked individual differences in conflict adaptation to distinct brain regions. However, the network-based neural mechanisms subserving the individual differences of the conflict adaptation effect have not been studied. The present study employed a psychophysiological interaction (PPI) analysis with a color-naming Stroop task to examine this issue. The main results were as follows: (1) the anterior cingulate cortex (ACC)-seeded PPI revealed the involvement of the salience network (SN) in conflict adaptation, while the posterior parietal cortex (PPC)-seeded PPI revealed the engagement of the central executive network (CEN). (2) Participants with high conflict adaptation effect showed higher intra-CEN connectivity and lower intra-SN connectivity; while those with low conflict adaptation effect showed higher intra-SN connectivity and lower intra-CEN connectivity. (3) The PPC-centered intra-CEN connectivity positively predicted the conflict adaptation effect; while the ACC-centered intra-SN connectivity had a negative correlation with this effect. In conclusion, our data demonstrated that conflict adaptation is likely supported by the CEN and the SN, providing a new perspective on studying individual differences in conflict adaptation on the basis of large-scale networks. Copyright © 2015 Elsevier Ltd. All rights reserved.

Temporal and spatial variability of frost-free seasons in the Great Lakes region of the United States

Science.gov (United States)

Lejiang Yu; Shiyuan Zhong; Xindi Bian; Warren E. Heilman; Jeffrey A. Andresen

2014-01-01

The frequency and timing of frost events and the length of the growing season are critical limiting factors in many human and natural ecosystems. This study investigates the temporal and spatial variability of the date of last spring frost (LSF), the date of first fall frost (FFF), and the length of the frost-free season (FFS) in the Great Lakes region of the United...

Intra- and inter- correlative responses among fruits physical traits ...

African Journals Online (AJOL)

Intra- and inter- correlative responses among fruits physical traits, seedling growth parameters and fruit and nut proximate qualities of the Nigerian shea nut tree ... Results indicated that the first three PCA axes retained explained 96.3% of total variability among seedling provenances, revealing that leaf area, seedling girth, ...

Intra-individual variability in day-to-day and month-to-month measurements of physical activity and sedentary behaviour at work and in leisure-time among Danish adults

DEFF Research Database (Denmark)

Lunde Pedersen, Eva Sophie; Danquah, I H; Petersen, C B

2016-01-01

in accelerometer derived data on sedentary behaviour and physical activity at work and in leisure-time during week days among Danish office employees. METHODS: We included control participants (n = 135) from the Take a Stand! Intervention; a cluster randomized controlled trial conducted in 19 offices. Sitting time....... RESULTS: Results of this study showed that the number of days needed to obtain a reliability of 80% when measuring sitting time was 4.7 days for work and 5.5 days for leisure time. For physical activity at work, 4.0 days and 4.2 days were required to measure steps and MVPA, respectively. During leisure...... time, more monitoring time was needed to reliably estimate physical activity (6.8 days for steps and 5.8 days for MVPA). CONCLUSIONS: The number of measurement days needed to reliably estimate activity patterns was greater for leisure time than for work time. The domain specific variability is of great...

Variability of morphometric characteristics of the leaves of European white elm from the area of Great War Island

Directory of Open Access Journals (Sweden)

Devetaković Jovana

2013-01-01

Full Text Available The European White Elm (Ulmus effusa Willd. is indicated as a rare and endangered species in the growing stock of the Republic of Serbia. In the area of Great War Island, its natural populations were reduced to 56 registered trees, which occur in three spatially isolated subpopulations. On the basis of the research conducted on the level of variability of adaptible morphometric characteristics of leaves from 14 selected test trees of European White Elm, it can be concluded that the degree of interpopulation variability is satisfactory, which is a good basis for the conservation of the available gene pool.

Climate and climate variability of the wind power resources in the Great Lakes region of the United States

Science.gov (United States)

X. Li; S. Zhong; X. Bian; W.E. Heilman

2010-01-01

The climate and climate variability of low-level winds over the Great Lakes region of the United States is examined using 30 year (1979-2008) wind records from the recently released North American Regional Reanalysis (NARR), a three-dimensional, high-spatial and temporal resolution, and dynamically consistent climate data set. The analyses focus on spatial distribution...

The Great Cross-Border Bank Deleveraging: Supply Constraints and Intra-Group Frictions

NARCIS (Netherlands)

Cerutti, E.; Claessens, S.

2014-01-01

International banks greatly reduced their direct cross-border and local affiliates’ lending as the global financial crisis strained balance sheets, lowered borrower demand, and changed government policies. Using bilateral, lender-borrower countrydata and controlling for credit demand, we show that

Intra- and interspecific trait variations reveal functional relationships between specific leaf area and soil niche within a subtropical forest.

Science.gov (United States)

He, Dong; Chen, Yongfa; Zhao, Kangning; Cornelissen, J H C; Chu, Chengjin

2018-02-03

How functional traits vary with environmental conditions is of fundamental importance in trait-based community ecology. However, how intraspecific variability in functional traits is connected to species distribution is not well understood. This study investigated inter- and intraspecific variation of a key functional trait, i.e. specific leaf area (leaf area per unit dry mass; SLA), in relation to soil factors and tested if trait variation is more closely associated with specific environmental regimes for low-variability species than for high-variability species. In a subtropical evergreen forest plot (50 ha, southern China), 106 700 leaves from 5335 individuals of 207 woody species were intensively collected, with 30 individuals sampled for most species to ensure a sufficient sample size representative of intraspecific variability. Soil conditions for each plant were estimated by kriging from more than 1700 observational soil locations across the plot. Intra- and interspecific variation in SLA were separately related to environmental factors. Based on the species-specific variation of SLA, species were categorized into three groups: low-, intermediate- and high-intraspecific variability. Intraspecific habitat ranges and the strength of SLA-habitat relationships were compared among these three groups. Interspecific variation in SLA overrides the intraspecific variation (77 % vs. 8 %). Total soil nitrogen (TN, positively) and total organic carbon (TOC, negatively) are the most important explanatory factors for SLA variation at both intra- and interspecific levels. SLA, both within and between species, decreases with decreasing soil nitrogen availability. As predicted, species with low intraspecific variability in SLA have narrower habitat ranges with respect to soil TOC and TN and show a stronger SLA-habitat association than high-variability species. For woody plants low SLA is a phenotypic and probably adaptive response to nitrogen stress, which drives the

Fatigue shifts and scatters heart rate variability in elite endurance athletes.

Directory of Open Access Journals (Sweden)

Laurent Schmitt

Full Text Available PURPOSE: This longitudinal study aimed at comparing heart rate variability (HRV in elite athletes identified either in 'fatigue' or in 'no-fatigue' state in 'real life' conditions. METHODS: 57 elite Nordic-skiers were surveyed over 4 years. R-R intervals were recorded supine (SU and standing (ST. A fatigue state was quoted with a validated questionnaire. A multilevel linear regression model was used to analyze relationships between heart rate (HR and HRV descriptors [total spectral power (TP, power in low (LF and high frequency (HF ranges expressed in ms(2 and normalized units (nu] and the status without and with fatigue. The variables not distributed normally were transformed by taking their common logarithm (log10. RESULTS: 172 trials were identified as in a 'fatigue' and 891 as in 'no-fatigue' state. All supine HR and HRV parameters (Beta±SE were significantly different (P<0.0001 between 'fatigue' and 'no-fatigue': HRSU (+6.27±0.61 bpm, logTPSU (-0.36±0.04, logLFSU (-0.27±0.04, logHFSU (-0.46±0.05, logLF/HFSU (+0.19±0.03, HFSU(nu (-9.55±1.33. Differences were also significant (P<0.0001 in standing: HRST (+8.83±0.89, logTPST (-0.28±0.03, logLFST (-0.29±0.03, logHFST (-0.32±0.04. Also, intra-individual variance of HRV parameters was larger (P<0.05 in the 'fatigue' state (logTPSU: 0.26 vs. 0.07, logLFSU: 0.28 vs. 0.11, logHFSU: 0.32 vs. 0.08, logTPST: 0.13 vs. 0.07, logLFST: 0.16 vs. 0.07, logHFST: 0.25 vs. 0.14. CONCLUSION: HRV was significantly lower in 'fatigue' vs. 'no-fatigue' but accompanied with larger intra-individual variance of HRV parameters in 'fatigue'. The broader intra-individual variance of HRV parameters might encompass different changes from no-fatigue state, possibly reflecting different fatigue-induced alterations of HRV pattern.

Handheld mechanical nociceptive threshold testing in dairy cows – intra-individual variation, inter-observer agreement and variation over time

Science.gov (United States)

Raundal, Peter M; Andersen, Pia H; Toft, Nils; Forkman, Björn; Munksgaard, Lene; Herskin, Mette S

2014-01-01

Objective To examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed. Study design Prospective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time. Animals One hundred and fifteen healthy, loose-housed Danish Holstein cattle. Methods We evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0–10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0–1000 gf). Each cow received 5–6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant. Results The CVs did not differ [range 0.34–0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01). Conclusion and clinical relevance All methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia. PMID:24734991

From John Lee to John Gottman: Recognizing Intra- and Interpersonal Differences to Promote Marital Satisfaction

Directory of Open Access Journals (Sweden)

Claire Kimberly

2013-10-01

Full Text Available Since Extension agents work with a variety of families, there is a desperate need to further our understanding of how to educate diverse communities on a family-related topic. Focused on assisting those teaching marital education to a diverse population, this study attempts to understand how individual differences impact relationship satisfaction and marital communication. Based on John Gottman’s research on marital communication and John Lee’s six loves styles, 653 participants completed a survey to further understanding of the relationship between inter- and intrapersonal variables. Results revealed that marital communication and love styles accounted for 54.6% of the variance in marital satisfaction regardless of difference in demographics. Results of this study provide a resource for educators and practitioners to use with diverse clientele, while also emphasizing the need to understand both intra- and interpersonal variables when working with families.

Variability in negative emotions among individuals with chronic low back pain: relationships with pain and function.

Science.gov (United States)

Gerhart, James I; Burns, John W; Bruehl, Stephen; Smith, David A; Post, Kristina M; Porter, Laura S; Schuster, Erik; Buvanendran, Asokumar; Fras, Anne Marie; Keefe, Francis J

2017-11-13

Chronic pain is associated with elevated negative emotions, and resources needed to adaptively regulate these emotions can be depleted during prolonged pain. Studies of links between pain, function, and negative emotions in people with chronic pain, however, have focused almost exclusively on relationships among mean levels of these factors. Indexes that may reflect aspects of emotion regulation have typically not been analyzed. We propose that 1 index of emotion regulation is variability in emotion over time as opposed to average emotion over time. The sample was 105 people with chronic low back pain and 105 of their pain-free spouses. They completed electronic diary measures 5x/d for 14 consecutive days, producing 70 observations per person from which we derived estimates of within-subject variance in negative emotions. Location-scale models were used to simultaneously model predictors of both mean level and variance in patient negative emotions over time. Patients reported significantly more variability in negative emotions compared to their spouses. Patients who reported higher average levels of pain, pain interference, and downtime reported significantly higher levels of variability in negative emotions. Spouse-observed pain and pain behaviors were also associated with greater variability in patients' negative emotions. Test of the inverse associations between negative emotion level and variability in pain and function were significant but weaker in magnitude. These findings support the notion that chronic pain may erode negative emotion regulation resources, to the potential detriment of intra- and inter-personal function.

Kelvin wave coupling from TIMED and GOCE: Inter/intra-annual variability and solar activity effects

Science.gov (United States)

Gasperini, Federico; Forbes, Jeffrey M.; Doornbos, Eelco N.; Bruinsma, Sean L.

2018-06-01

The primary mechanism through which energy and momentum are transferred from the lower atmosphere to the thermosphere is through the generation and propagation of atmospheric waves. It is becoming increasingly evident that a few waves from the tropical wave spectrum preferentially propagate into the thermosphere and contribute to modify satellite drag. Two of the more prominent and well-established tropical waves are Kelvin waves: the eastward-propagating 3-day ultra-fast Kelvin wave (UFKW) and the eastward-propagating diurnal tide with zonal wave number 3 (DE3). In this work, Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperatures at 110 km and Gravity field and steady-state Ocean Circulation Explorer (GOCE) neutral densities and cross-track winds near 260 km are used to demonstrate vertical coupling in this height regime due to the UFKW and DE3. Significant inter- and intra-annual variability is found in DE3 and the UFKW, with evidence of latitudinal broadening and filtering of the latitude structures with height due to the effect of dissipation and mean winds. Additionally, anti-correlation between the vertical penetration of these waves to the middle thermosphere and solar activity level is established and explained through the effect of molecular dissipation.

Automatic intra-modality brain image registration method

International Nuclear Information System (INIS)

Whitaker, J.M.; Ardekani, B.A.; Braun, M.

1996-01-01

Full text: Registration of 3D images of brain of the same or different subjects has potential importance in clinical diagnosis, treatment planning and neurological research. The broad aim of our work is to produce an automatic and robust intra-modality, brain image registration algorithm for intra-subject and inter-subject studies. Our algorithm is composed of two stages. Initial alignment is achieved by finding the values of nine transformation parameters (representing translation, rotation and scale) that minimise the nonoverlapping regions of the head. This is achieved by minimisation of the sum of the exclusive OR of two binary head images, produced using the head extraction procedure described by Ardekani et al. (J Comput Assist Tomogr, 19:613-623, 1995). The initial alignment successfully determines the scale parameters and gross translation and rotation parameters. Fine alignment uses an objective function described for inter-modality registration in Ardekani et al. (ibid.). The algorithm segments one of the images to be aligned into a set of connected components using K-means clustering. Registration is achieved by minimising the K-means variance of the segmentation induced in the other image. Similarity of images of the same modality makes the method attractive for intra-modality registration. A 3D MR image, with voxel dimensions, 2x2x6 mm, was misaligned. The registered image shows visually accurate registration. The average displacement of a pixel from its correct location was measured to be 3.3 mm. The algorithm was tested on intra-subject MR images and was found to produce good qualitative results. Using the data available, the algorithm produced promising qualitative results in intra-subject registration. Further work is necessary in its application to intersubject registration, due to large variability in brain structure between subjects. Clinical evaluation of the algorithm for selected applications is required

Systematically variable planktonic carbon metabolism along a land-to-lake gradient in a Great Lakes coastal zone.

Science.gov (United States)

Weinke, Anthony D; Kendall, Scott T; Kroll, Daniel J; Strickler, Eric A; Weinert, Maggie E; Holcomb, Thomas M; Defore, Angela A; Dila, Deborah K; Snider, Michael J; Gereaux, Leon C; Biddanda, Bopaiah A

2014-11-01

During the summers of 2002-2013, we measured rates of carbon metabolism in surface waters of six sites across a land-to-lake gradient from the upstream end of drowned river-mouth Muskegon Lake (ML) (freshwater estuary) to 19 km offshore in Lake Michigan (LM) (a Great Lake). Despite considerable inter-year variability, the average rates of gross production (GP), respiration (R) and net production (NP) across ML (604 ± 58, 222 ± 22 and 381 ± 52 µg C L -1 day -1 , respectively) decreased steeply in the furthest offshore LM site (22 ± 3, 55 ± 17 and -33 ± 15 µg C L -1 day -1 , respectively). Along this land-to-lake gradient, GP decreased by 96 ± 1%, whereas R only decreased by 75 ± 9%, variably influencing the carbon balance along this coastal zone. All ML sites were consistently net autotrophic (mean GP:R = 2.7), while the furthest offshore LM site was net heterotrophic (mean GP:R = 0.4). Our study suggests that pelagic waters of this Great Lakes coastal estuary are net carbon sinks that transition into net carbon sources offshore. Reactive and dynamic estuarine coastal zones everywhere may contribute similarly to regional and global carbon cycles.

ABCB1 genetic variability and methadone dosage requirements in opioid-dependent individuals.

Science.gov (United States)

Coller, Janet K; Barratt, Daniel T; Dahlen, Karianne; Loennechen, Morten H; Somogyi, Andrew A

2006-12-01

The most common treatment for opioid dependence is substitution therapy with another opioid such as methadone. The methadone dosage is individualized but highly variable, and program retention rates are low due in part to nonoptimal dosing resulting in withdrawal symptoms and further heroin craving and use. Methadone is a substrate for the P-glycoprotein transporter, encoded by the ABCB1 gene, which regulates central nervous system exposure. This retrospective study aimed to investigate the influence of ABCB1 genetic variability on methadone dose requirements. Genomic deoxyribonucleic acid was isolated from opioid-dependent subjects (n = 60) and non-opioid-dependent control subjects (n = 60), and polymerase chain reaction-restriction fragment length polymorphism and allele-specific polymerase chain reaction were used to determine the presence of single nucleotide polymorphisms at positions 61, 1199, 1236, 2677, and 3435. ABCB1 haplotypes were inferred with PHASE software (version 2.1). There were no significant differences in the allele or genotype frequencies of the individual single nucleotide polymorphisms or haplotypes between the 2 populations. ABCB1 genetic variability influenced daily methadone dose requirements, such that subjects carrying 2 copies of the wild-type haplotype required higher doses compared with those with 1 copy and those with no copies (98.3 +/- 10.4, 58.6 +/- 20.9, and 55.4 +/- 26.1 mg/d, respectively; P = .029). In addition, carriers of the AGCTT haplotype required significantly lower doses than noncarriers (38.0 +/- 16.8 and 61.3 +/- 24.6 mg/d, respectively; P = .04). Although ABCB1 genetic variability is not related to the development of opioid dependence, identification of variant haplotypes may, after larger prospective studies have been performed, provide clinicians with a tool for methadone dosage individualization.

MRI assessment of tenosynovitis in children with juvenile idiopathic arthritis: inter- and intra-observer variability

International Nuclear Information System (INIS)

Lambot, Karen; Brunelle, Francis; Boavida, Peter; Damasio, Maria Beatrice; Tanturri de Horatio, Laura; Barbuti, Domenico; Desgranges, Marie; Bader-Meunier, Brigitte; Quartier, Pierre; Malattia, Clara; Bracaglia, Claudia; Ording Mueller, Lil-Sofie; Elie, Caroline; Rosendahl, Karen

2013-01-01

There is sparse knowledge about grading tenosynovitis using MRI. The purpose of this study was to assess the reliability of a tenosynovitis MRI scoring system in juvenile idiopathic arthritis. Children with juvenile idiopathic arthritis and wrist involvement were enrolled in two paediatric centres, from October 2006 to January 2010. The extensor (compartments II, IV and VI) and flexor tendons were assessed for the presence of tenosynovitis on T1-weighted postcontrast fat-saturated MR images and were scored from 0 (normal) to 2 (moderate to severe) by two observers independently. Intra- and interobserver agreement was assessed. Ninety children (age range: 5-18.5 years) were included, of whom 34 had tenosynovitis involving extensors and 28 had tenosynovitis involving flexors. A total of 360 tendon areas were analysed, of which 114 had tenosynovitis (86/270 extensors and 28/90 flexors). Intra-reader 1 agreement was excellent for the extensors (k = 0.82-0.91) and for the flexors (k = 0.85); intra-reader 2 agreement was moderate to good for the extensors (k = 0.51-0.72) and good for the flexors (k = 0.64). Inter-reader agreement was good for the extensors (k = 0.69-0.73) and moderate for the flexors (k = 0.49). The proposed MRI scoring system for the assessment of wrist tenosynovitis in juvenile idiopathic arthritis appears feasible with an observer agreement sufficient for clinical use. (orig.)

MRI assessment of tenosynovitis in children with juvenile idiopathic arthritis: inter- and intra-observer variability

Energy Technology Data Exchange (ETDEWEB)

Lambot, Karen; Brunelle, Francis [Hopital Necker-Enfants Malades, Department of Paediatric Radiology, Paris (France); Boavida, Peter [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom); Damasio, Maria Beatrice [Ospedale Pediatrico Gaslini, Department of Radiology, Genoa (Italy); Tanturri de Horatio, Laura; Barbuti, Domenico [Ospedale Pediatrico Bambino Gesu, Department of Radiology, Rome (Italy); Desgranges, Marie; Bader-Meunier, Brigitte; Quartier, Pierre [Hopital Necker-Enfants Malades, Department of Paediatric Immunology, Hematology and Rheumatology, APHP French Reference Center ' ' Arthrites juveniles' ' , Paris (France); Malattia, Clara [University of Genoa, Department of Paediatrics, Genoa (Italy); Bracaglia, Claudia [Ospedale Pediatrico Bambino Gesu, Department of Paediatrics, Rome (Italy); Ording Mueller, Lil-Sofie [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom); University Hospital of North Norway, Department of Radiology, Tromsoe (Norway); Elie, Caroline [Paris Descartes University, Department of Biostatistics, Hopital Necker-Enfants Malades, Paris (France); Rosendahl, Karen [Great Ormond Street Hospital, Department of Radiology, London (United Kingdom); Haukeland University Hospital, Department of Radiology, Bergen (Norway)

2013-07-15

There is sparse knowledge about grading tenosynovitis using MRI. The purpose of this study was to assess the reliability of a tenosynovitis MRI scoring system in juvenile idiopathic arthritis. Children with juvenile idiopathic arthritis and wrist involvement were enrolled in two paediatric centres, from October 2006 to January 2010. The extensor (compartments II, IV and VI) and flexor tendons were assessed for the presence of tenosynovitis on T1-weighted postcontrast fat-saturated MR images and were scored from 0 (normal) to 2 (moderate to severe) by two observers independently. Intra- and interobserver agreement was assessed. Ninety children (age range: 5-18.5 years) were included, of whom 34 had tenosynovitis involving extensors and 28 had tenosynovitis involving flexors. A total of 360 tendon areas were analysed, of which 114 had tenosynovitis (86/270 extensors and 28/90 flexors). Intra-reader 1 agreement was excellent for the extensors (k = 0.82-0.91) and for the flexors (k = 0.85); intra-reader 2 agreement was moderate to good for the extensors (k = 0.51-0.72) and good for the flexors (k = 0.64). Inter-reader agreement was good for the extensors (k = 0.69-0.73) and moderate for the flexors (k = 0.49). The proposed MRI scoring system for the assessment of wrist tenosynovitis in juvenile idiopathic arthritis appears feasible with an observer agreement sufficient for clinical use. (orig.)

Assessing potential impacts of climate change and variability on the Great Lakes-St. Lawrence Basin: A binational approach

International Nuclear Information System (INIS)

Quinn, F.H.; Mortsch, L.D.

1997-01-01

The potential impacts of climate change and variability on the Great Lakes environment are serious and complex. The Great Lakes-St. Lawrence Basin is home to 42.5 million US and Canadian citizens and is the industrial and commercial heartland of both nations. The region is rich in human and natural resources, with diverse economic activities and substantial infrastructure which would be affected by major shifts in climate. For example, water level changes could affect wetland distribution and functioning; reductions in streamflow would alter assimilative capacities while warmer water temperatures would influence spring and fall turnover and incidence of anoxia. A binational program has been initiated to conduct interdisciplinary, integrated impact assessments for the Great Lakes-St. Lawrence River Basin. The goal of this program is to undertake interdisciplinary, integrated studies to improve the understanding of the complex interactions between climate, the environment, and socioeconomic systems in order to develop informed regional adaptation responses

Variabilidade intra-avaliador e inter-avaliadores de medidas antropométricas - DOI: 10.4025/actascihealthsci.v29i1.98 Intra-observer and inter-observers variability of anthropometric measures- DOI: 10.4025/actascihealthsci.v29i1.98

Directory of Open Access Journals (Sweden)

Edna Regina de Oliveira

2007-12-01

Full Text Available O objetivo do estudo foi avaliar a variabilidade intra e inter-avaliadores de medidas antropométricas realizadas por três antropometristas considerados experientes mediante o cálculo dos erros técnicos de medida (ETM. Para esse fim, foi selecionada uma amostra de 21 voluntários (25,7 ± 7,5 anos, sendo 12 homens e 9 mulheres. Foram consideradas as medidas de peso corporal (kg, estatura (cm, circunferências (cm do braço direito relaxado, abdômen, quadril e coxa, e da espessura das dobras cutâneas (mm tricipital, subescapular, suprailíaca, abdômen, coxa e panturrilha medial. As medidas foram realizadas em 2 dias consecutivos, sempre no período da tarde, envolvendo os mesmos equipamentos e os mesmos voluntários. Os resultados apontaram a ocorrência de ETMs acima dos recomendados para aceitabilidade, tanto a variabilidade intra-avaliador como inter-avaliadores, sugerindo, portanto, a importância e a necessidade de treinamento específico dos antropometristas.The aim of this study was to evaluate the intra and inter-observer reliability in the anthropometric measures of three expert observers through the technical error of measure (TEM. For this end, 21 healthy volunteers (25.7 ± 7.5 years took part in the study, being 12 males and 9 females. The following aspects were analyzed: body weigh (kg, stature (cm, circumferences (cm of relaxed right arm, abdomen, hip and thigh, and skinfold thickness (mm of triceps, subescapular, supra-iliac, abdomen, thigh and calf medial. The measures were made in 2 different days, always in the afternoon, with the same equipments and in the same volunteers. The results pointed the occurrence of TEMs out of the recommended patterns, in both intra-observer and inter-observers variability. This fact showed the importance and need of specific training of the observers.

Individual Variability in Aerobic Fitness Adaptations to 70-d of Bed Rest and Exercise Training

Science.gov (United States)

Downs, Meghan; Buxton, Roxanne; Goetchius, Elizabeth; DeWitt, John; Ploutz-Snyder, Lori

2016-01-01

Change in maximal aerobic capacity (VO2pk) in response to exercise training and disuse is highly variable among individuals. Factors that could contribute to the observed variability (lean mass, daily activity, diet, sleep, stress) are not routinely controlled in studies. The NASA bed rest (BR) studies use a highly controlled hospital based model as an analog of spaceflight. In this study, diet, hydration, physical activity and light/dark cycles were precisely controlled and provided the opportunity to investigate individual variability. PURPOSE. Evaluate the contribution of exercise intensity and lean mass on change in VO2pk during 70-d of BR or BR + exercise. METHODS. Subjects completed 70-d of BR alone (CON, N=9) or BR + exercise (EX, N=17). The exercise prescription included 6 d/wk of aerobic exercise at 70 - 100% of max and 3 d/wk of lower body resistance exercise. Subjects were monitored 24 hr/d. VO2pk and lean mass (iDXA) were measured pre and post BR. ANOVA was used to evaluate changes in VO2pk pre to post BR. Subjects were retrospectively divided into high and low responders based on change in VO2pk (CON > 20% loss, n=5; EX >10% loss, n=4, or 5% gain, n=4) to further understand individual variability. RESULTS. VO2pk decreased from pre to post BR in CON (Pexercise intensity. CONCLUSION. Change in VO2pk in response to disuse and exercise was highly variable among individuals, even in this tightly controlled study. Loss in lean mass accounts for a significant degree of variability in the CON; however, training induced gains in VO2pk appear unrelated to lean mass or exercise intensity.

Intra- and Inter-islet Synchronization of Metabolically Driven Insulin Secretion

DEFF Research Database (Denmark)

Pedersen, Morten Gram; Bertram, Richard; Sherman, Arthur

2005-01-01

mechanisms for intra-islet and inter-islet synchronization. We show that electrical coupling is sufficient to synchronize both electrical bursting activity and metabolic oscillations. We also demonstrate that islets can synchronize by mutually entraining each other by their effects on a simple model "liver......,'' which responds to the level of insulin secretion by adjusting the blood glucose concentration in an appropriate way. Since all islets are exposed to the blood, the distributed islet-liver system can synchronize the individual islet insulin oscillations. Thus, we demonstrate how intra-islet and inter...

Rates of ingestion and their variability between individual calanoid copepods: Direct observations

Energy Technology Data Exchange (ETDEWEB)

Paffenhoefer, G.A.; Lewis, K.D. [Skidaway Inst. of Oceanography, Savannah, GA (United States); Bundy, M.H. [Skidaway Inst. of Oceanography, Savannah, GA (United States)]|[Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE); Metz, C. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE)

1995-12-01

The goals of this study were to determine rates of ingestion and fecal pellet release, and their variability, for individual planktonic copepods over extended periods of time (>20 min). Ingestions and rejections of individual cells of the diatom Thalassiosira eccentrica by a adult females of the calanoid Paracalanus aculeatus were directly quantified by observing individual copepods continuously at cell concentrations ranging from 0.1 to 1.2 mm{sup 3} l{sup {minus}1}. Average ingestion rates increased with increasing food concentration, but were not significantly different between 0.3 and 1.0 mm{sup 3} l{sup {minus}1} (9.8 and 32.7 {mu}g Cl{sup {minus}1}) of T.eccentrica. Rates of cell rejections were low and similar at 0.1 and 0.3. but were significantly higher at 1.0 mm{sup 3} l{sup {minus}1}. The coefficients of variation for average ingestion rates of individual copepods hardly differed between food concentrations, ranging from 17 to 22%, and were close to those for average fecal pellet release intervals which ranged from 15 to 21%. A comparison between individuals at each food concentration found no significant differences at 1.0; at 0.1 and 0.3 mm{sup 3} l{sup {minus}1}, respectively, ingestion rates of four out of five females did not differ significantly from each other. Average intervals between fecal pellet releases were similar at 0.3 and 1.0 mm{sup 3} l{sup {minus}1}. Fecal pellet release intervals between individuals were significantly different at each food concentration; these significant differences were attributed to rather narrow ranges of pellet release intervals of each individual female. Potential sources/causes of variability in the sizes and rates of copepods in the ocean are evaluated.

The Role of Individual Differences and Situational Variables in the Use of Workplace Sexual Identity Management Strategies.

Science.gov (United States)

Reed, Louren; Leuty, Melanie E

2016-07-01

Examination of individual difference variables have been largely ignored within research on the use of workplace sexual identity management strategies. The current study examined personality traits (extraversion, openness, and neuroticism), facets of sexual identity development (identity confusion, internalized heterosexism), and situational variables (e.g., perceptions of workplace climate and heterosexism) in explaining the use of management strategies, as well as possible interactions between individual and situational factors. Perceptions of the workplace climate toward lesbian and gay individuals significantly related to the use each of the management strategies, and Internalized Heterosexism was found to significantly predict the use of the Explicitly Out strategy. Most interactions between individual difference and situational variables were not supported, with the exception of an interaction between workplace heterosexism and internalized homophobia in explaining the use of the Explicitly Out strategy.

Distribution and predictors of wing shape and size variability in three sister species of solitary bees.

Directory of Open Access Journals (Sweden)

Simon Dellicour

Full Text Available Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal

Distribution and predictors of wing shape and size variability in three sister species of solitary bees.

Science.gov (United States)

Dellicour, Simon; Gerard, Maxence; Prunier, Jérôme G; Dewulf, Alexandre; Kuhlmann, Michael; Michez, Denis

2017-01-01

Morphological traits can be highly variable over time in a particular geographical area. Different selective pressures shape those traits, which is crucial in evolutionary biology. Among these traits, insect wing morphometry has already been widely used to describe phenotypic variability at the inter-specific level. On the contrary, fewer studies have focused on intra-specific wing morphometric variability. Yet, such investigations are relevant to study potential convergences of variation that could highlight micro-evolutionary processes. The recent sampling and sequencing of three solitary bees of the genus Melitta across their entire species range provides an excellent opportunity to jointly analyse genetic and morphometric variability. In the present study, we first aim to analyse the spatial distribution of the wing shape and centroid size (used as a proxy for body size) variability. Secondly, we aim to test different potential predictors of this variability at both the intra- and inter-population levels, which includes genetic variability, but also geographic locations and distances, elevation, annual mean temperature and precipitation. The comparison of spatial distribution of intra-population morphometric diversity does not reveal any convergent pattern between species, thus undermining the assumption of a potential local and selective adaptation at the population level. Regarding intra-specific wing shape differentiation, our results reveal that some tested predictors, such as geographic and genetic distances, are associated with a significant correlation for some species. However, none of these predictors are systematically identified for the three species as an important factor that could explain the intra-specific morphometric variability. As a conclusion, for the three solitary bee species and at the scale of this study, our results clearly tend to discard the assumption of the existence of a common pattern of intra-specific signal/structure within the

An Intra-Group Perspective on Leader Preferences

DEFF Research Database (Denmark)

Bøggild, Troels; Laustsen, Lasse

2016-01-01

This article argues that followers’ preferences for dominant leadership vary according to two types of exploitation risks from other individuals within the group. Previous work demonstrates that contexts of inter-group war and peace make followers prefer dominant- and non-dominant-looking leaders......, respectively. We add an intra-group perspective to this literature. Four original studies demonstrate that contexts with high risks of free-riding and criminal behavior from other group members (i.e., horizontal exploitation) increase preferences for dominant-looking leaders, whereas contexts with high risks...... of unresponsive, self-interested behavior from leaders themselves (i.e., vertical exploitation) decrease preferences for dominant-looking leaders. Moreover, within this framework of intra-group exploitation risks we show that followers prefer leaders from another vis-à-vis their own ethnic coalition to look less...

Eye-size variability in deep-sea lanternfishes (Myctophidae): an ecological and phylogenetic study.

Science.gov (United States)

de Busserolles, Fanny; Fitzpatrick, John L; Paxton, John R; Marshall, N Justin; Collin, Shaun P

2013-01-01

One of the most common visual adaptations seen in the mesopelagic zone (200-1000 m), where the amount of light diminishes exponentially with depth and where bioluminescent organisms predominate, is the enlargement of the eye and pupil area. However, it remains unclear how eye size is influenced by depth, other environmental conditions and phylogeny. In this study, we determine the factors influencing variability in eye size and assess whether this variability is explained by ecological differences in habitat and lifestyle within a family of mesopelagic fishes characterized by broad intra- and interspecific variance in depth range and luminous patterns. We focus our study on the lanternfish family (Myctophidae) and hypothesise that lanternfishes with a deeper distribution and/or a reduction of bioluminescent emissions have smaller eyes and that ecological factors rather than phylogenetic relationships will drive the evolution of the visual system. Eye diameter and standard length were measured in 237 individuals from 61 species of lanternfishes representing all the recognised tribes within the family in addition to compiling an ecological dataset including depth distribution during night and day and the location and sexual dimorphism of luminous organs. Hypotheses were tested by investigating the relationship between the relative size of the eye (corrected for body size) and variations in depth and/or patterns of luminous-organs using phylogenetic comparative analyses. Results show a great variability in relative eye size within the Myctophidae at all taxonomic levels (from subfamily to genus), suggesting that this character may have evolved several times. However, variability in eye size within the family could not be explained by any of our ecological variables (bioluminescence and depth patterns), and appears to be driven solely by phylogenetic relationships.

Intra-industry momentum and product market competition around the world

Directory of Open Access Journals (Sweden)

Ting Li

2016-06-01

Full Text Available This paper examines the relationship between product market competition and intra-industry momentum returns. Based on 12,982 firm observations from 19 developed markets for the period of 1990–2010, I find that buying winners and selling losers in competitive industries generates significantly higher momentum profits than that in concentrated industries. The higher the intensity of product market competition, the larger are the intra-industry momentum returns. The results are robust to sub-samples (periods of the U.S., non-U.S. countries, the G7 countries, 1990–2000, and 2001–2010. I further employ the nearness of a stock's price to the 52-week high to determine past winners and losers and find stronger results. I also compare intra-industry momentum returns with Jegadeesh and Titman (1993 individual stock momentum and Moskowitz and Grinblatt (1999 inter-industry momentum strategies. My results suggest that intra-industry momentum strategy outperforms the latter two strategies in most cases. The overall results are consistent with the notion that severe product market competition induces managers to improve financial performance.

Does bisphenol A induce superfeminization in Marisa cornuarietis? Part I: intra- and inter-laboratory variability in test endpoints.

Science.gov (United States)

Forbes, Valery E; Selck, Henriette; Palmqvist, Annemette; Aufderheide, John; Warbritton, Ryan; Pounds, Nadine; Thompson, Roy; van der Hoeven, Nelly; Caspers, Norbert

2007-03-01

It has been claimed that bisphenol A (BPA) induces superfeminization in the freshwater gastropod, Marisa cornuarietis. To explore the reproducibility of prior work, here we present results from a three-laboratory study, the objectives of which were to determine the mean and variability in test endpoints (i.e., adult fecundity, egg hatchability, and juvenile growth) under baseline conditions and to identify the sources of variability. A major source of variability for all of the measured endpoints was due to differences within and among individuals. With few exceptions, variability among laboratories and among replicate tanks within laboratories contributed little to the observed variability in endpoints. The results highlight the importance of obtaining basic knowledge of husbandry requirements and baseline information on life-history traits of potential test species prior to designing toxicity test protocols. Understanding of the levels and sources of endpoint variability is essential so that statistically robust and ecologically relevant tests of chemicals can be conducted.

Intra-abdominal fat: Comparison of computed tomography fat segmentation and bioimpedance spectroscopy.

Science.gov (United States)

Finch, Peter

2017-06-01

Intra-abdominal fat is an important factor in determining the metabolic syndrome/insulin resistance, and thus the risk of diabetes and ischaemic heart disease. Computed Tomography (CT) fat segmentation represents a defined method of quantifying intra-abdominal fat, with attendant radiation risks. Bioimpedance spectroscopy may offer a method of assessment without any risks to the patients. A comparison is made of these two methods. This was a preliminary study of the utility of multifrequency bioimpedance spectroscopy of the mid abdomen as a measure of intra-abdominal fat, by comparison with fat segmentation of an abdominal CT scan in the -30 to -190 HU range. There was a significant (P abdominal fat and mid-upper arm circumference, as well as the bioimpedance parameter, the R/S ratio. Multivariate analysis showed that these were the only independant variables and allowed the derivation of a formula to estimate intra-abdominal fat: IAF = 0.02 × MAC - 0.757 × R/S + 0.036. Circumabdominal bioimpedance spectroscopy may prove a useful method of assessing intra-abdominal fat, and may be suitable for use in studies to enhance other measures of body composition, such as mid-upper arm circumference.

Hydroxyl layer: trend of number density and intra-annual variability

Science.gov (United States)

Sonnemann, G. R.; Hartogh, P.; Berger, U.; Grygalashvyly, M.

2015-06-01

The layer of vibrationally excited hydroxyl (OH*) near the mesopause in Earth's atmosphere is widely used to derive the temperature at this height and to observe dynamical processes such as gravity waves. The concentration of OH* is controlled by the product of atomic hydrogen, with ozone creating a layer of enhanced concentration in the mesopause region. However, the basic influences on the OH* layer are atomic oxygen and temperature. The long-term monitoring of this layer provides information on a changing atmosphere. It is important to know which proportion of a trend results from anthropogenic impacts on the atmosphere and which proportion reflects natural variations. In a previous paper (Grygalashvyly et al., 2014), the trend of the height of the layer and the trend in temperature were investigated particularly in midlatitudes on the basis of our coupled dynamic and chemical transport model LIMA (Leibniz Institute Middle Atmosphere). In this paper we consider the trend for the number density between the years 1961 and 2009 and analyze the reason of the trends on a global scale. Further, we consider intra-annual variations. Temperature and wind have the strongest impacts on the trend. Surprisingly, the increase in greenhouse gases (GHGs) has no clear influence on the chemistry of OH*. The main reason for this lies in the fact that, in the production term of OH*, if atomic hydrogen increases due to increasing humidity of the middle atmosphere by methane oxidation, ozone decreases. The maximum of the OH* layer is found in the mesopause region and is very variable. The mesopause region is a very intricate domain marked by changeable dynamics and strong gradients of all chemically active minor constituents determining the OH* chemistry. The OH* concentration responds, in part, very sensitively to small changes in these parameters. The cause for this behavior is given by nonlinear reactions of the photochemical system being a nonlinear enforced chemical oscillator

Hydroxyl layer: trend of number density and intra-annual variability

Directory of Open Access Journals (Sweden)

G. R. Sonnemann

2015-06-01

Full Text Available The layer of vibrationally excited hydroxyl (OH* near the mesopause in Earth's atmosphere is widely used to derive the temperature at this height and to observe dynamical processes such as gravity waves. The concentration of OH* is controlled by the product of atomic hydrogen, with ozone creating a layer of enhanced concentration in the mesopause region. However, the basic influences on the OH* layer are atomic oxygen and temperature. The long-term monitoring of this layer provides information on a changing atmosphere. It is important to know which proportion of a trend results from anthropogenic impacts on the atmosphere and which proportion reflects natural variations. In a previous paper (Grygalashvyly et al., 2014, the trend of the height of the layer and the trend in temperature were investigated particularly in midlatitudes on the basis of our coupled dynamic and chemical transport model LIMA (Leibniz Institute Middle Atmosphere. In this paper we consider the trend for the number density between the years 1961 and 2009 and analyze the reason of the trends on a global scale. Further, we consider intra-annual variations. Temperature and wind have the strongest impacts on the trend. Surprisingly, the increase in greenhouse gases (GHGs has no clear influence on the chemistry of OH*. The main reason for this lies in the fact that, in the production term of OH*, if atomic hydrogen increases due to increasing humidity of the middle atmosphere by methane oxidation, ozone decreases. The maximum of the OH* layer is found in the mesopause region and is very variable. The mesopause region is a very intricate domain marked by changeable dynamics and strong gradients of all chemically active minor constituents determining the OH* chemistry. The OH* concentration responds, in part, very sensitively to small changes in these parameters. The cause for this behavior is given by nonlinear reactions of the photochemical system being a nonlinear enforced

Apresentação do processo de confecção da cápsula do aparelho de amplificação sonora individual intra-aural por meio de digitalização Presenting the process of making the capsule of intra-aural hearing aid through digitization

Directory of Open Access Journals (Sweden)

Jerusa Roberta Massola de Oliveira

2013-02-01

Full Text Available OBJETIVO: o objetivo deste estudo é apresentar as etapas do processo de confecção da cápsula do aparelho de amplificação sonora individual intra-aural por meio da digitalização. MÉTODO: foram utilizadas otoplásticas e os equipamentos Legato para realizar o escaneamento e Envisiontec para sinterização, ambos disponibilizados pela empresa Phonak. RESULTADOS: os resultados sinalizam para cápsula de aparelho de amplificação sonora individual intra-aurais, plenamente satisfatórias, sendo constatada todas as vantagens documentadas pelo fabricante. CONCLUSÃO: a nova técnica de confecção de cápsula por meio de processo de digitalização demonstrou ser eficaz com alta qualidade e mantendo a impressão fiel da orelha, além de durabilidade significativa.PURPOSE: the objective of this study is to present the steps involved in making the capsule of intra-aural hearing aids through scanning. METHOD: we used the Legato otoplasty equipment in order to perform scanning and Enisiontec for sintering, both provided by the company Phonak. RESULTS: the results point out to capsule-ear hearing aid, as being fully satisfying and with all the benefits documented by the manufacturer. CONCLUSION: a new technique in order to make the capsule through the scanning process has been proven effective and with high quality and keeping the faithful imprint of the ear, in addition to significant durability.

Inter- and intra-individual variation in allele-specific DNA methylation and gene expression in children conceived using assisted reproductive technology.

Directory of Open Access Journals (Sweden)

Nahid Turan

2010-07-01

Full Text Available Epidemiological studies have reported a higher incidence of rare disorders involving imprinted genes among children conceived using assisted reproductive technology (ART, suggesting that ART procedures may be disruptive to imprinted gene methylation patterns. We examined intra- and inter-individual variation in DNA methylation at the differentially methylated regions (DMRs of the IGF2/H19 and IGF2R loci in a population of children conceived in vitro or in vivo. We found substantial variation in allele-specific methylation at both loci in both groups. Aberrant methylation of the maternal IGF2/H19 DMR was more common in the in vitro group, and the overall variance was also significantly greater in the in vitro group. We estimated the number of trophoblast stem cells in each group based on approximation of the variance of the binomial distribution of IGF2/H19 methylation ratios, as well as the distribution of X chromosome inactivation scores in placenta. Both of these independent measures indicated that placentas of the in vitro group were derived from fewer stem cells than the in vivo conceived group. Both IGF2 and H19 mRNAs were significantly lower in placenta from the in vitro group. Although average birth weight was lower in the in vitro group, we found no correlation between birth weight and IGF2 or IGF2R transcript levels or the ratio of IGF2/IGF2R transcript levels. Our results show that in vitro conception is associated with aberrant methylation patterns at the IGF2/H19 locus. However, very little of the inter- or intra-individual variation in H19 or IGF2 mRNA levels can be explained by differences in maternal DMR DNA methylation, in contrast to the expectations of current transcriptional imprinting models. Extraembryonic tissues of embryos cultured in vitro appear to be derived from fewer trophoblast stem cells. It is possible that this developmental difference has an effect on placental and fetal growth.

Boundary Spanners and Intra-MNC Knowledge Sharing

DEFF Research Database (Denmark)

Minbaeva, Dana; Santangelo, Grazia D.

2018-01-01

intermediaries between many individuals from within and outside their organizations. They are well connected internally and externally and share knowledge across MNC units to a greater extent than non-boundary spanners. However, their contribution to knowledge sharing should not be taken for granted......Research summary: We examine the conditions under which boundary spanners positively contribute to intra-MNC knowledge sharing. Specifically, we argue that the knowledge-sharing behavior of boundary spanners should not be taken for granted, as it is affected by the individual's motivation to share...... knowledge and is contingent upon the immediate organizational context in which the individual is located. An analysis of data covering 482 individuals located in different business units of a Danish MNC confirms our arguments. Managerial summary: Boundary spanners are employees who act as knowledge...

The Impact of Individual Attitudinal and Organisational Variables on Workplace Environmentally Friendly Behaviours

OpenAIRE

Manika, D; Wells, VK; Gregory-Smith, D; Gentry, M

2015-01-01

Although research on corporate social responsibility (CSR) has grown steadily, little research has focused on CSR at the individual level. In addition, research on the role of environmental friendly organizational citizenship behaviors (OCBs) within CSR initiatives is scarce. In response to this gap and recent calls for further research on both individual and organizational variables of employees' environmentally friendly, or green, behaviors, this article sheds light on the influence of thes...

Intra and inter ‘local climate zone’ variability of air temperature as observed by crowdsourced citizen weather stations in Berlin, Germany

Directory of Open Access Journals (Sweden)

Daniel Fenner

2017-11-01

Full Text Available A one-year data set for the year 2015 of near-surface air temperature (T$T$, crowdsourced from ‘Netatmo’ citizen weather stations (CWS in Berlin, Germany, and surroundings was analysed. The CWS data set, which has been quality-checked and filtered in a previous study, consists of T$T$ measurements from several hundred CWS. It was investigated (1 how CWS are distributed among urban and rural environments, as represented by ‘local climate zones’ (LCZ, (2 how LCZ are characterised in T$T$ along the annual cycle and concerning intra-LCZ T$T$ variability, and (3 if significant T$T$ differences between LCZ (ΔT$\\Delta T$ can be detected with CWS data. Further, it was investigated how the results from CWS compare to reference data from standard meteorological measurement stations. It can be shown that all ‘urban’ LCZ are covered by CWS, but only few CWS are located in ‘natural’ LCZ (e.g. forests or urban parks. CWS data along the annual cycle show generally good agreement to reference data, though for some LCZ monthly means between both data sets differ up to 1 K. Intra-LCZ T$T$ variability is particularly large during night-time. Statistically significant ΔT$\\Delta T$ can be detected with CWS data between various LCZ pairs, particularly for structurally dissimilar LCZ, and the results are in agreement with existing literature on LCZ or the urban heat island. Furthermore, annual mean ΔT$\\Delta T$ in CWS data agree well with reference data, thus showing the potential of CWS data for long-term studies. Several challenges related to crowdsourced CWS data need further investigation, namely missing meta data, the non-standard measurement locations, the imbalanced availability in time and space, and potentials to combine CWS and reference data to benefit from the main advantages of both, i.e., the large number of stations and the high quality of data, respectively.

Intra-fraction motion of the prostate is a random walk

Science.gov (United States)

Ballhausen, H.; Li, M.; Hegemann, N.-S.; Ganswindt, U.; Belka, C.

2015-01-01

A random walk model for intra-fraction motion has been proposed, where at each step the prostate moves a small amount from its current position in a random direction. Online tracking data from perineal ultrasound is used to validate or reject this model against alternatives. Intra-fraction motion of a prostate was recorded by 4D ultrasound (Elekta Clarity system) during 84 fractions of external beam radiotherapy of six patients. In total, the center of the prostate was tracked for 8 h in intervals of 4 s. Maximum likelihood model parameters were fitted to the data. The null hypothesis of a random walk was tested with the Dickey-Fuller test. The null hypothesis of stationarity was tested by the Kwiatkowski-Phillips-Schmidt-Shin test. The increase of variance in prostate position over time and the variability in motility between fractions were analyzed. Intra-fraction motion of the prostate was best described as a stochastic process with an auto-correlation coefficient of ρ = 0.92  ±  0.13. The random walk hypothesis (ρ = 1) could not be rejected (p = 0.27). The static noise hypothesis (ρ = 0) was rejected (p test rejected the null hypothesis ρ = 1 in 25% to 32% of cases. On average, the Kwiatkowski-Phillips-Schmidt-Shin test rejected the null hypothesis ρ = 0 with a probability of 93% to 96%. The variance in prostate position increased linearly over time (r2 = 0.9  ±  0.1). Variance kept increasing and did not settle at a maximum as would be expected from a stationary process. There was substantial variability in motility between fractions and patients with maximum aberrations from isocenter ranging from 0.5 mm to over 10 mm in one patient alone. In conclusion, evidence strongly suggests that intra-fraction motion of the prostate is a random walk and neither static (like inter-fraction setup errors) nor stationary (like a cyclic motion such as breathing, for example). The prostate tends to drift away from the isocenter during a fraction, and

Intra-fraction motion of the prostate is a random walk

International Nuclear Information System (INIS)

Ballhausen, H; Li, M; Hegemann, N-S; Ganswindt, U; Belka, C

2015-01-01

A random walk model for intra-fraction motion has been proposed, where at each step the prostate moves a small amount from its current position in a random direction. Online tracking data from perineal ultrasound is used to validate or reject this model against alternatives. Intra-fraction motion of a prostate was recorded by 4D ultrasound (Elekta Clarity system) during 84 fractions of external beam radiotherapy of six patients. In total, the center of the prostate was tracked for 8 h in intervals of 4 s. Maximum likelihood model parameters were fitted to the data. The null hypothesis of a random walk was tested with the Dickey–Fuller test. The null hypothesis of stationarity was tested by the Kwiatkowski–Phillips–Schmidt–Shin test. The increase of variance in prostate position over time and the variability in motility between fractions were analyzed. Intra-fraction motion of the prostate was best described as a stochastic process with an auto-correlation coefficient of ρ = 0.92  ±  0.13. The random walk hypothesis (ρ = 1) could not be rejected (p = 0.27). The static noise hypothesis (ρ = 0) was rejected (p < 0.001). The Dickey–Fuller test rejected the null hypothesis ρ = 1 in 25% to 32% of cases. On average, the Kwiatkowski–Phillips–Schmidt–Shin test rejected the null hypothesis ρ = 0 with a probability of 93% to 96%. The variance in prostate position increased linearly over time (r 2 = 0.9  ±  0.1). Variance kept increasing and did not settle at a maximum as would be expected from a stationary process. There was substantial variability in motility between fractions and patients with maximum aberrations from isocenter ranging from 0.5 mm to over 10 mm in one patient alone. In conclusion, evidence strongly suggests that intra-fraction motion of the prostate is a random walk and neither static (like inter-fraction setup errors) nor stationary (like a cyclic motion such as breathing, for example). The prostate tends to

Variability in Second Language Learning: The Roles of Individual Differences, Learning Conditions, and Linguistic Complexity

Science.gov (United States)

Tagarelli, Kaitlyn M.; Ruiz, Simón; Vega, José Luis Moreno; Rebuschat, Patrick

2016-01-01

Second language learning outcomes are highly variable, due to a variety of factors, including individual differences, exposure conditions, and linguistic complexity. However, exactly how these factors interact to influence language learning is unknown. This article examines the relationship between these three variables in language learners.…

Intra-Site Variability in the Still Bay Fauna at Blombos Cave: Implications for Explanatory Models of the Middle Stone Age Cultural and Technological Evolution.

Directory of Open Access Journals (Sweden)

Emmanuel Discamps

Full Text Available To explain cultural and technological innovations in the Middle Stone Age (MSA of southern Africa, scholars invoke several factors. A major question in this research theme is whether MSA technocomplexes are adapted to a particular set of environmental conditions and subsistence strategies or, on the contrary, to a wide range of different foraging behaviours. While faunal studies provide key information for addressing these factors, most analyses do not assess intra-technocomplex variability of faunal exploitation (i.e. variability within MSA phases. In this study, we assess the spatial variability of the Still Bay fauna in one phase (M1 of the Blombos Cave sequence. Analyses of taxonomic composition, taphonomic alterations and combustion patterns reveal important faunal variability both across space (lateral variation in the post-depositional history of the deposits, spatial organisation of combustion features and over time (fine-scale diachronic changes throughout a single phase. Our results show how grouping material prior to zooarchaeological interpretations (e.g. by layer or phase can induce a loss of information. Finally, we discuss how multiple independent subdivisions of archaeological sequences can improve our understanding of both the timing of different changes (for example in technology, culture, subsistence, environment and how they may be inter-related.

Reconciling the Log-Linear and Non-Log-Linear Nature of the TSH-Free T4 Relationship: Intra-Individual Analysis of a Large Population.

Science.gov (United States)

Rothacker, Karen M; Brown, Suzanne J; Hadlow, Narelle C; Wardrop, Robert; Walsh, John P

2016-03-01

The TSH-T4 relationship was thought to be inverse log-linear, but recent cross-sectional studies report a complex, nonlinear relationship; large, intra-individual studies are lacking. Our objective was to analyze the TSH-free T4 relationship within individuals. We analyzed data from 13 379 patients, each with six or more TSH/free T4 measurements and at least a 5-fold difference between individual median TSH and minimum or maximum TSH. Linear and nonlinear regression models of log TSH on free T4 were fitted to data from individuals and goodness of fit compared by likelihood ratio testing. Comparing all models, the linear model achieved best fit in 31% of individuals, followed by quartic (27%), cubic (15%), null (12%), and quadratic (11%) models. After eliminating least favored models (with individuals reassigned to best fitting, available models), the linear model fit best in 42% of participants, quartic in 43%, and null model in 15%. As the number of observations per individual increased, so did the proportion of individuals in whom the linear model achieved best fit, to 66% in those with more than 20 observations. When linear models were applied to all individuals and averaged according to individual median free T4 values, variations in slope and intercept indicated a nonlinear log TSH-free T4 relationship across the population. The log TSH-free T4 relationship appears linear in some individuals and nonlinear in others, but is predominantly linear in those with the largest number of observations. A log-linear relationship within individuals can be reconciled with a non-log-linear relationship in a population.

Reliability and short-term intra-individual variability of telomere length measurement using monochrome multiplexing quantitative PCR.

Directory of Open Access Journals (Sweden)

Sangmi Kim

Full Text Available Studies examining the association between telomere length and cancer risk have often relied on measurement of telomere length from a single blood draw using a real-time PCR technique. We examined the reliability of telomere length measurement using sequential samples collected over a 9-month period.Relative telomere length in peripheral blood was estimated using a single tube monochrome multiplex quantitative PCR assay in blood DNA samples from 27 non-pregnant adult women (aged 35 to 74 years collected in 7 visits over a 9-month period. A linear mixed model was used to estimate the components of variance for telomere length measurements attributed to variation among women and variation between time points within women. Mean telomere length measurement at any single visit was not significantly different from the average of 7 visits. Plates had a significant systematic influence on telomere length measurements, although measurements between different plates were highly correlated. After controlling for plate effects, 64% of the remaining variance was estimated to be accounted for by variance due to subject. Variance explained by time of visit within a subject was minor, contributing 5% of the remaining variance.Our data demonstrate good short-term reliability of telomere length measurement using blood from a single draw. However, the existence of technical variability, particularly plate effects, reinforces the need for technical replicates and balancing of case and control samples across plates.

Biologic variability and correlation of platelet function testing in healthy dogs.

Science.gov (United States)

Blois, Shauna L; Lang, Sean T; Wood, R Darren; Monteith, Gabrielle

2015-12-01

Platelet function tests are influenced by biologic variability, including inter-individual (CVG ) and intra-individual (CVI ), as well as analytic (CVA ) variability. Variability in canine platelet function testing is unknown, but if excessive, would make it difficult to interpret serial results. Additionally, the correlation between platelet function tests is poor in people, but not well described in dogs. The aims were to: (1) identify the effect of variation in preanalytic factors (venipuncture, elapsed time until analysis) on platelet function tests; (2) calculate analytic and biologic variability of adenosine diphosphate (ADP) and arachidonic acid (AA)-induced thromboelastograph platelet mapping (TEG-PM), ADP-, AA-, and collagen-induced whole blood platelet aggregometry (WBA), and collagen/ADP and collagen/epinephrine platelet function analysis (PFA-CADP, PFA-CEPI); and (3) determine the correlation between these variables. In this prospective observational trial, platelet function was measured once every 7 days, for 4 consecutive weeks, in 9 healthy dogs. In addition, CBC, TEG-PM, WBA, and PFA were performed. Overall coefficients of variability ranged from 13.3% to 87.8% for the platelet function tests. Biologic variability was highest for AA-induced maximum amplitude generated during TEG-PM (MAAA; CVG = 95.3%, CVI = 60.8%). Use of population-based reference intervals (RI) was determined appropriate only for PFA-CADP (index of individuality = 10.7). There was poor correlation between most platelet function tests. Use of population-based RI appears inappropriate for most platelet function tests, and tests poorly correlate with one another. Future studies on biologic variability and correlation of platelet function tests should be performed in dogs with platelet dysfunction and those treated with antiplatelet therapy. © 2015 American Society for Veterinary Clinical Pathology.

Is the Classification of International Trade in Horizontal and Vertical Intra-Industry Trade Usable?

DEFF Research Database (Denmark)

Nielsen, Jørgen Ulff-Møller; Lüthje, Teit

2001-01-01

with vertical intra-industry trade (between Germany and France) making up 50-60%. The high level of vertical intra-industry trade probably covers up many products shifting between e.g. vertical and horizontal intra-industry. The statement from the literature that the European integration process involves heavy......Abstract On the basis of OECD trade statistics at SITC 5 digit level for the period 1961-1999 we show the classification of international trade in (a) inter-industry trade and (b) horizontal intra-industry and (c) vertical intra-industry trade used in the empirical trade literature to be non stable...... at the individual product level. This indicates that this type of statistical classification based on unit-values is probably not very useful. On the other hand, we also show in accordance with the literature that the aggregate distribution of trade into the three categories apparently is rather stable...

Intra-Hour Dispatch and Automatic Generator Control Demonstration with Solar Forecasting - Final Report

Energy Technology Data Exchange (ETDEWEB)

Coimbra, Carlos F. M. [Univ. of California, San Diego, CA (United States

2016-02-25

In this project we address multiple resource integration challenges associated with increasing levels of solar penetration that arise from the variability and uncertainty in solar irradiance. We will model the SMUD service region as its own balancing region, and develop an integrated, real-time operational tool that takes solar-load forecast uncertainties into consideration and commits optimal energy resources and reserves for intra-hour and intra-day decisions. The primary objectives of this effort are to reduce power system operation cost by committing appropriate amount of energy resources and reserves, as well as to provide operators a prediction of the generation fleet’s behavior in real time for realistic PV penetration scenarios. The proposed methodology includes the following steps: clustering analysis on the expected solar variability per region for the SMUD system, Day-ahead (DA) and real-time (RT) load forecasts for the entire service areas, 1-year of intra-hour CPR forecasts for cluster centers, 1-year of smart re-forecasting CPR forecasts in real-time for determination of irreducible errors, and uncertainty quantification for integrated solar-load for both distributed and central stations (selected locations within service region) PV generation.

Urban Socio-economic Development and Intra-city travel in Ogun ...

African Journals Online (AJOL)

This study is on influence of socio-economic development of urban centers on intra-city trip generation in Ogun state, Nigeria. The proportion of the aggregate socio-economic variables in each city was used to rank the cities in hierarchical order of development while the average household trip per week was used to rank ...

Inter- and intra-observer variability associated with the use of the Mirels' scoring system for metastatic bone lesions.

LENUS (Irish Health Repository)

Mac Niocaill, Ruairi F

2011-01-01

Metastatic bone disease is increasing in association with ever-improving medical management of osteophylic malignant conditions. The precise timing of surgical intervention for secondary lesions in long bones can be difficult to determine. This paper aims to evaluate a classic scoring system. All radiographs were examined twice by three orthopaedic oncologists and scored according to the Mirels\\' scoring system. The Kappa statistic was used for the purpose of statistical analysis. The results show agreement between observers (κ = 0.35-0.61) for overall scores at the two time intervals. Inter-observer agreement was also seen with subset analysis of size (κ = 0.27-0.60), site (κ = 0.77-1.0) and nature of the lesion (κ = 0.55-0.81). Similarly, low levels of intra-observer variability were noted for each of the three surgeons (κ= 0.34, 0.39, and 0.78, respectively). These results indicate a reliable, repeatable assessment of bony metastases. We continue to advocate its use in the management of patients with long bone metastases.

Technical Analysis in Forex : A Strategy for Individual Trader in Intra-Day Trading

OpenAIRE

Linden, Miikka

2009-01-01

The goal of the thesis was to create a simple and profitable strategy for Foreign Exchange Market (forex) currency trading. Forex is an interesting international market, which is becom-ing globally more and more popular. The author has a strong interest in forex and he had no-ticed how many trading strategies are very complicated and difficult to use. The meaning was to study what kind of simple trading strategy would be profitable in forex. The target of the study was intra-day traders, who ...

Flicker Mitigation by Individual Pitch Control of Variable Speed Wind Turbines With DFIG

DEFF Research Database (Denmark)

Zhang, Yunqian; Chen, Zhe; Hu, Weihao

2014-01-01

generatorto investigate the flicker emission and mitigation issues. An individual pitch control (IPC) strategy is proposed to reduce the flicker emission at different wind speed conditions. The IPC scheme is proposed and the individual pitch controller is designed according to the generator active power...... and the azimuth angle of the wind turbine. The simulations are performed on the NREL (National Renewable Energy Laboratory) 1.5-MW upwind reference wind turbine model. Simulation results show that damping the generator active power by IPC is an effective means for flicker mitigation of variable speed wind......Due to the wind speed variation, wind shear and tower shadow effects, grid connected wind turbines are the sources of power fluctuations which may produce flicker during continuous operation. This paper presents a model of an MW-level variable-speed wind turbine with a doubly fed induction...

Cognitive endophenotypes of attention deficit/hyperactivity disorder and intra-subject variability in patients with autism spectrum disorder.

Science.gov (United States)

Biscaldi, M; Bednorz, N; Weissbrodt, K; Saville, C W N; Feige, B; Bender, S; Klein, C

2016-07-01

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) have previously been studied mainly in isolation from each other. However the two conditions may be aetiologically related and thus show overlap in aetiologically relevant functions. In order to address this question of potential aetiological overlap between ADHD and ASD, the present study set out to investigate putative endophenotypes of ADHD in N=33 typically developing (TD) children and N=28 patients with ASD that were (ASD+) or were not (ASD-) co-morbid for ADHD. With regard to both the cognitive endophenotype candidates (working memory, inhibition, temporal processing) and intra-subject variability (ISV) the pattern of abnormalities was inconsistent. Furthermore, the overall profile of ASD-TD differences was extremely similar to the pattern of differences between the ASD+ and ASD- sub-groups, suggesting that any abnormalities found were due to the comorbid ASD subgroup. This held in particular for ISV, which did not show in patients with ASD the task-general increase that is common in ADHD samples. Altogether, the present results do not support the hypothesis of aetiological overlap between ASD and ADHD. Copyright © 2016 Elsevier B.V. All rights reserved.

Intra and interobserver variability of intrapartum transperineal ultrasound measurements with contraction and pushing.

Science.gov (United States)

Sainz, José A; Fernández-Palacín, Ana; Borrero, Carlota; Aquise, Adriana; Ramos, Zenaida; García-Mejido, José A

2018-04-01

The aim of this study was to evaluate the inter- and intraobserver correlation of the different intrapartum-transperineal-ultrasound-parameters(ITU) (angle of progression (AoP), progression-distance (PD), head-direction (HD), midline-angle (MLA) and head-perineum distance (HPD)) with contraction and pushing. We evaluated 28 nulliparous women at full dilatation under epidural analgesia. We performed a transperineal ultrasound evaluating AoP and PD in the longitudinal plane, and MLA and HPD in the transverse plane. Interclass correlation coefficients (ICC) with 95% CIs and Bland-Altman analysis were used to assess intra- and interobserver measurement's repeatability. The ICC of the ITU for the same observer was adequate for all the parameters (p pushing under epidural analgesia. Impact statement What is already known on this subject: The intrapartum transperineal ultrasound parameters can be used with contraction and pushing under epidural analgesia. What the results of this study add to what we know: ITU may be used to evaluate the difficulty of instrumental delivery/to evaluate the difficulty of instrumentation in vaginal operative deliveries and this study concludes that ITU is reproducible during uterine contraction with pushing. What the implications are of these findings for clinical practice and/or further research: Therefore, ITU could be used without difficulty with an adequate intra- and interobserver correlation for the prediction of instrumentation difficulty in operative vaginal deliveries.

Psychobiological Factors Affecting Cortisol Variability in Human-Dog Dyads.

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Iris Schöberl

Full Text Available Stress responses within dyads are modulated by interactions such as mutual emotional support and conflict. We investigated dyadic psychobiological factors influencing intra-individual cortisol variability in response to different challenging situations by testing 132 owners and their dogs in a laboratory setting. Salivary cortisol was measured and questionnaires were used to assess owner and dog personality as well as owners' social attitudes towards the dog and towards other humans. We calculated the individual coefficient of variance of cortisol (iCV = sd/mean*100 over the different test situations as a parameter representing individual variability of cortisol concentration. We hypothesized that high cortisol variability indicates efficient and adaptive coping and a balanced individual and dyadic social performance. Female owners of male dogs had lower iCV than all other owner gender-dog sex combinations (F = 14.194, p<0.001, whereas owner Agreeableness (NEO-FFI scaled positively with owner iCV (F = 4.981, p = 0.028. Dogs of owners high in Neuroticism (NEO-FFI and of owners who were insecure-ambivalently attached to their dogs (FERT, had low iCV (F = 4.290, p = 0.041 and F = 5.948, p = 0.016, as had dogs of owners with human-directed separation anxiety (RSQ or dogs of owners with a strong desire of independence (RSQ (F = 7.661, p = 0.007 and F = 9.192, p = 0.003. We suggest that both owner and dog social characteristics influence dyadic cortisol variability, with the human partner being more influential than the dog. Our results support systemic approaches (i.e. considering the social context in science and in counselling.

Visit-to-visit cholesterol variability correlates with coronary atheroma progression and clinical outcomes.

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Clark, Donald; Nicholls, Stephen J; St John, Julie; Elshazly, Mohamed B; Kapadia, Samir R; Tuzcu, E Murat; Nissen, Steven E; Puri, Rishi

2018-04-21

Utilizing serial intravascular ultrasonography (IVUS), we aimed to exam the association of intra-individual lipid variability, coronary atheroma progression, and clinical outcomes. We performed a post hoc patient-level analysis of nine clinical trials involving 4976 patients with coronary artery disease who underwent serial coronary IVUS in the setting of a range of medical therapies. We assessed the associations between progression in percent atheroma volume (ΔPAV), clinical outcomes, and visit-to-visit lipid variability including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, total cholesterol (TC)/HDL-C, and apolipoprotein B (ApoB). Variability of lipid parameters was measured using intra-individual standard deviation over 3, 6, 12, 18, and 24 months. Atherogenic lipoprotein variability significantly associated with ΔPAV [odds ratio (95% confidence interval; P-value), LDL-C: 1.09 (1.02, 1.17, P = 0.01); non-HDL-C: 1.10 (1.02, 1.18, P = 0.01); TC/HDL-C: 1.14 (1.06, 1.24, P = 0.001); ApoB: 1.13 (1.03, 1.24, P = 0.01)]. Survival curves revealed significant stepwise relationships between cumulative major adverse cardiovascular events and increasing quartiles of atherogenic lipoprotein variability at 24-months follow-up (log-rank P C). Stronger associations were noted between achieved lipoprotein levels and ΔPAV [LDL-C: 1.27 (1.17, 1.39; P C: 1.32 (1.21, 1.45; P C: 1.31 (1.19, 1.45; P < 0.001); ApoB: 1.20 (1.07, 1.35; P = 0.003)]. Greater visit-to-visit variability in atherogenic lipoprotein levels significantly associates with coronary atheroma progression and clinical outcomes, although the association between achieved atherogenic lipoproteins and atheroma progression appears stronger. These data highlight the importance of achieving low and consistent atherogenic lipoprotein levels to promote plaque regression and improve clinical outcomes.

Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

International Nuclear Information System (INIS)

Antonsen, Lisbeth; Thayssen, Per; Junker, Anders; Veien, Karsten Tange; Hansen, Henrik Steen; Hansen, Knud Nørregaard; Hougaard, Mikkel; Jensen, Lisette Okkels

2015-01-01

Purpose: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~ 10–15 μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). Methods: Ten N-BESs (213 cross sectional areas (CSAs) and 1897 struts) imaged with OCT 6 months post-implantation were randomly selected and analyzed by 2 experienced analysts, and the same 10 N-BESs were analyzed by one of the analysts 3 months later. Further, 2 consecutive pullbacks randomly performed in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. Results: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1% ± 1.4% and 0.5% ± 3.2%. Interobserver variability also proved to be low: − 2.1% ± 3.3% and 2.1% ± 4.6%, and moreover, very restricted intra-catheter variation was observed: 0.02% ± 6.8% and − 0.18% ± 5.2%. The intraobserver-, interobserver- and intra-catheter reliability for the qualitative evaluation of strut coverage was found to be: kappa (κ) = 0.91 (95% confidence interval (CI): 0.88–0.93, p < 0.01), κ = 0.88 (95% CI: 0.85–0.91, p < 0.01), and κ = 0.73 (95% CI: 0.68–0.78, p < 0.01), respectively. Conclusions: FD-OCT is a reproducible and reliable imaging tool for quantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage. - Highlights: • Frequency-domain optical coherence tomography (FD-OCT) is increasingly adopted in the catherization laboratories. • This

Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

Energy Technology Data Exchange (ETDEWEB)

Antonsen, Lisbeth, E-mail: Lisbeth.antonsen@rsyd.dk; Thayssen, Per; Junker, Anders; Veien, Karsten Tange; Hansen, Henrik Steen; Hansen, Knud Nørregaard; Hougaard, Mikkel; Jensen, Lisette Okkels

2015-12-15

Purpose: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~ 10–15 μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). Methods: Ten N-BESs (213 cross sectional areas (CSAs) and 1897 struts) imaged with OCT 6 months post-implantation were randomly selected and analyzed by 2 experienced analysts, and the same 10 N-BESs were analyzed by one of the analysts 3 months later. Further, 2 consecutive pullbacks randomly performed in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. Results: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1% ± 1.4% and 0.5% ± 3.2%. Interobserver variability also proved to be low: − 2.1% ± 3.3% and 2.1% ± 4.6%, and moreover, very restricted intra-catheter variation was observed: 0.02% ± 6.8% and − 0.18% ± 5.2%. The intraobserver-, interobserver- and intra-catheter reliability for the qualitative evaluation of strut coverage was found to be: kappa (κ) = 0.91 (95% confidence interval (CI): 0.88–0.93, p < 0.01), κ = 0.88 (95% CI: 0.85–0.91, p < 0.01), and κ = 0.73 (95% CI: 0.68–0.78, p < 0.01), respectively. Conclusions: FD-OCT is a reproducible and reliable imaging tool for quantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage. - Highlights: • Frequency-domain optical coherence tomography (FD-OCT) is increasingly adopted in the catherization laboratories. • This

Optimal ranking regime analysis of intra- to multidecadal U.S. climate variability. Part I: Temperature

Science.gov (United States)

The Optimal Ranking Regime (ORR) method was used to identify intra- to multi-decadal (IMD) time windows containing significant ranking sequences in U.S. climate division temperature data. The simplicity of the ORR procedure’s output – a time series’ most significant non-overlapping periods of high o...

Life Satisfaction Among Mothers of Individuals with Prader-Willi Syndrome.

Science.gov (United States)

Shivers, Carolyn M; Leonczyk, Caroline L; Dykens, Elisabeth M

2016-06-01

Mothers of individuals with Prader-Willi syndrome (PWS) often experience numerous stressors, even when compared to mothers of children with other intellectual and developmental disabilities. Despite this, these mothers show great variability in self-reported life satisfaction. Using data from a longitudinal study of individuals with PWS and their families, the present study analyzed factors related to maternal life satisfaction, both cross-sectionally and over time. Results show that both child factors (e.g., behavior problems, hyperphagia) and maternal factors (e.g., stress, coping style) were significantly related to maternal life satisfaction. However, none of the tested variables predicted change in life satisfaction over time. Research and practice implications are discussed.

Intra-puparial development of the females of Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae

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José Roberto Pujol-Luz

2012-09-01

Full Text Available Intra-puparial development of the females of Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae. The chronology and morphological changes that take place during intra-puparial development of Chrysomya albiceps is described based on 254 specimens reared in the laboratory. Larvae were obtained from the eggs laid by a single female. The pre-pupae were separated according to the reduction of larval length and the degree of pigmentation and sclerotization of the cuticle. After pupation, 10 individuals were fixed in Carnoy's solution and preserved in 70% ethanol, 10 individuals were fixed every 3 hours up to complete the first 24 hours (n = 80, the remaining individuals were fixed every six hours up to the 90th hour (n = 110 when 54 females emerged. The pupae were immersed in 5% formic acid for 48 hours and maintained in 70% ethanol, and then dissected and analyzed. C. albiceps shows four intra-puparial stages, each of which were described and compared with those described for Musca domestica, Calliphora erythrocephala, Sarcophaga bullata, Cuterebra tenebrosa, Oestrus ovis and Dermatobia hominis. Four developmental stages may be described: (1 the larva-pupa apolysis, after three hours; (2 the criptocephalic pupa, after six hours; (3 the phanerocephalic pupa, after nine hours; (4 the pharate pupa, after nine hours. The pharate adult is completely formed after 81 hours.

Variability of morphometric caracteristics of one-year seedlings of different half-sib European White Elm (Ulmus effusa Wild. from the Great War Island

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Devetaković, J.

2013-12-01

Full Text Available European White Elm is recognized as a rare and endangered species in the forest fund of the Republic of Serbia. During the past century massive drying of elms occurred and the indications of their extinction appeared, which consequently led to a reduction in genetic diversity and the danger of genetic drift. In the area of the Great War Island near Belgrade we found 56 trees of European White Elm that are spatially divided into three subpopulations. In order to assess the genetic potential of European White Elm in the Great War Island and to define adequate conservation measures variability of 14 selected test trees progeny was rated. Results shows that the satisfactory variability within the popoulation exists, which is a good basis for the conservation of genepool available.

Breath acetone concentration; biological variability and the influence of diet

International Nuclear Information System (INIS)

Španěl, Patrik; Dryahina, Kseniya; Rejšková, Alžběta; Chippendale, Thomas W E; Smith, David

2011-01-01

Previous measurements of acetone concentrations in the exhaled breath of healthy individuals and the small amount of comparable data for individuals suffering from diabetes are briefly reviewed as a prelude to the presentation of new data on the sporadic and wide variations of breath acetone that occur in ostensibly healthy individuals. Data are also presented which show that following a ketogenic diet taken by eight healthy individuals their breath acetone concentrations increased up to five times over the subsequent 6 h. Similarly, the breath acetone increased six and nine times when a low carbohydrate diet was taken by two volunteers and remained high for the several days for which the diet was continued. These new data, together with the previous data, clearly indicate that diet and natural intra-individual biological and diurnal variability result in wide variations in breath acetone concentration. This places an uncertainty in the use of breath acetone alone to monitor blood glucose and glycaemic control, except and unless the individual acts as their own control and is cognizant of the need for dietary control. (note)

MRI assessment of knee osteoarthritis: Knee Osteoarthritis Scoring System (KOSS) - inter-observer and intra-observer reproducibility of a compartment-based scoring system

International Nuclear Information System (INIS)

Kornaat, Peter R.; Ceulemans, Ruth Y.T.; Kroon, Herman M.; Bloem, Johan L.; Riyazi, Naghmeh; Kloppenburg, Margreet; Carter, Wayne O.; Woodworth, Thasia G.

2005-01-01

To develop a scoring system for quantifying osteoarthritic changes of the knee as identified by magnetic resonance (MR) imaging, and to determine its inter- and intra-observer reproducibility, in order to monitor medical therapy in research studies. Two independent observers evaluated 25 consecutive MR examinations of the knee in patients with previously defined clinical symptoms and radiological signs of osteoarthritis. We acquired on a 1.5 T system: coronal and sagittal proton density- and T2-weighted dual spin echo (SE) images, sagittal three-dimensional T1-weighted gradient echo (GE) images with fat suppression, and axial dual turbo SE images with fat suppression. Images were scored for the presence of cartilaginous lesions, osteophytes, subchondral cysts, bone marrow edema, and for meniscal abnormalities. Presence and size of effusion, synovitis and Baker's cyst were recorded. All parameters were ranked on a previously defined, semiquantitative scale, reflecting increasing severity of findings. Kappa, weighted kappa and intraclass correlation coefficient (ICC) were used to determine inter- and intra-observer variability. Inter-observer reproducibility was good (ICC value 0.77). Inter- and intra-observer reproducibility for individual parameters was good to very good (inter-observer ICC value 0.63-0.91; intra-observer ICC value 0.76-0.96). The presented comprehensive MR scoring system for osteoarthritic changes of the knee has a good to very good inter-observer and intra-observer reproducibility. Thus the score form with its definitions can be used for standardized assessment of osteoarthritic changes to monitor medical therapy in research studies. (orig.)

Morphometric variability of Arctodiaptomus salinus (Copepoda) in the Mediterranean-Black Sea region.

Science.gov (United States)

Anufriieva, Elena V; Shadrin, Nickolai V

2015-11-18

Inter-species variability in morphological traits creates a need to know the range of variability of characteristics in the species for taxonomic and ecological tasks. Copepoda Arctodiaptomus salinus, which inhabits water bodies across Eurasia and North Africa, plays a dominant role in plankton of different water bodies-from fresh to hypersaline. This work assesses the intra- and inter-population morphometric variability of A. salinus in the Mediterranean-Black Sea region and discusses some observed regularities. The variability of linear body parameters and proportions was studied. The impacts of salinity, temperature, and population density on morphological characteristics and their variability can manifest themselves in different ways at the intra- and inter-population levels. A significant effect of salinity, pH and temperature on the body proportions was not found. Their intra-population variability is dependent on temperature and salinity. Sexual dimorphism of A. salinus manifests in different linear parameters, proportions, and their variability. There were no effects of temperature, pH and salinity on the female/male parameter ratio. There were significant differences in the body proportions of males and females in different populations. The influence of temperature, salinity, and population density can be attributed to 80%-90% of intra-population variability of A. salinus. However, these factors can explain less than 40% of inter-population differences. Significant differences in the body proportions of males and females from different populations may suggest that some local populations of A. salinus in the Mediterranean-Black Sea region are in the initial stages of differentiation.

Scan-rescan and intra-observer variability of magnetic resonance imaging of carotid atherosclerosis at 1.5 T and 3.0 T

International Nuclear Information System (INIS)

Vidal, Arvin; Wade, Trevor; Rutt, Brian K; Fenster, Aaron; Parraga, Grace; Bureau, Yves; Spence, J David

2008-01-01

Carotid atherosclerosis measurements for eight subjects at baseline and 14 ± 2 days later were examined using 1.5 T and 3.0 T magnetic resonance imaging (MRI). A single observer blinded to field strength, subject and timepoint manually segmented carotid artery wall and lumen boundaries in randomized images in five measurement trials. Mean increases in the signal-to-noise ratios (SNR) for T1-weighted images acquired at 3.0 T compared to 1.5 T were 90% (scan) and 80% (rescan). Despite significantly improved SNR and contrast-to-noise ratios (CNR) for images acquired at 3.0 T, vessel wall volume (VWV) intra-observer variability was not significantly different using coefficients of variation (COV), and intraclass correlation coefficients (ICC). VWV interscan variability and consistency at both field strengths were not statistically different (1.5 T/3.0 T COV = 5.7%/7.8%, R 2 = 0.96 for 1.5 T and R 2 = 0.87 for 3.0 T). A two-way analysis of variance showed a VWV dependence on field strength but not scan timepoint. In addition, a paired t-test showed significant differences in VWV measured at 3.0 T as compared to 1.5 T. These results suggest that although images acquired at 1.5 T have lower SNR and CNR VWV, measurement variability was not significantly different from 3.0 T VWV and that VWV is field-strength dependent which may be an important consideration for longitudinal studies.

Scan-rescan and intra-observer variability of magnetic resonance imaging of carotid atherosclerosis at 1.5 T and 3.0 T

Energy Technology Data Exchange (ETDEWEB)

Vidal, Arvin; Wade, Trevor; Rutt, Brian K; Fenster, Aaron; Parraga, Grace [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, N6A 5K8 (Canada); Bureau, Yves [Graduate Program in Biomedical Engineering, University of Western Ontario, London, N6A 5B9 (Canada); Spence, J David [Stroke Prevention and Atherosclerosis Research Centre, Robarts Research Institute, 1400 Western Road, London, N6A 5K8 (Canada)], E-mail: avidal@imaging.robarts.ca, E-mail: ybureau@lawsonimaging.ca, E-mail: twade@imaging.robarts.ca, E-mail: DSpence@robarts.ca, E-mail: brutt@imaging.robarts.ca, E-mail: afenster@imaging.robarts.ca, E-mail: gep@imaging.robarts.ca

2008-12-07

Carotid atherosclerosis measurements for eight subjects at baseline and 14 {+-} 2 days later were examined using 1.5 T and 3.0 T magnetic resonance imaging (MRI). A single observer blinded to field strength, subject and timepoint manually segmented carotid artery wall and lumen boundaries in randomized images in five measurement trials. Mean increases in the signal-to-noise ratios (SNR) for T1-weighted images acquired at 3.0 T compared to 1.5 T were 90% (scan) and 80% (rescan). Despite significantly improved SNR and contrast-to-noise ratios (CNR) for images acquired at 3.0 T, vessel wall volume (VWV) intra-observer variability was not significantly different using coefficients of variation (COV), and intraclass correlation coefficients (ICC). VWV interscan variability and consistency at both field strengths were not statistically different (1.5 T/3.0 T COV = 5.7%/7.8%, R{sup 2} = 0.96 for 1.5 T and R{sup 2} = 0.87 for 3.0 T). A two-way analysis of variance showed a VWV dependence on field strength but not scan timepoint. In addition, a paired t-test showed significant differences in VWV measured at 3.0 T as compared to 1.5 T. These results suggest that although images acquired at 1.5 T have lower SNR and CNR VWV, measurement variability was not significantly different from 3.0 T VWV and that VWV is field-strength dependent which may be an important consideration for longitudinal studies.

Individuals with Type 1 and Type 2 Diabetes Mellitus Trade Increased Hyperglycemia for Decreased Hypoglycemia When Glycemic Variability is not Improved.

Science.gov (United States)

Jangam, Sujit R; Hayter, Gary; Dunn, Timothy C

2018-02-01

Glycemic variability refers to oscillations in blood glucose within a day and differences in blood glucose at the same time on different days. Glycemic variability is linked to hypoglycemia and hyperglycemia. The relationship among these three important metrics is examined here, specifically to show how reduction in both hypo- and hyperglycemia risk is dependent on changes in variability. To understand the importance of glycemic variability in the simultaneous reduction of hypoglycemia and hyperglycemia risk, we introduce the glycemic risk plot-estimated HbA1c % (eA1c) vs. minutes below 70 mg/dl (MB70) with constant variability contours for predicting post-intervention risks in the absence of a change in glycemic variability. The glycemic risk plot illustrates that individuals who do not reduce glycemic variability improve one of the two metrics (hypoglycemia risk or hyperglycemia risk) at the cost of the other. It is important to reduce variability to improve both risks. These results were confirmed by data collected in a randomized controlled trial consisting of individuals with type 1 and type 2 diabetes on insulin therapy. For type 1, a total of 28 individuals out of 35 (80%) showed improvement in at least one of the risks (hypo and/or hyper) during the 100-day course of the study. Seven individuals (20%) showed improvement in both. Similar data were observed for type 2 where a total of 36 individuals out of 43 (84%) showed improvement in at least one risk and 8 individuals (19%) showed improvement in both. All individuals in the study who showed improvement in both hypoglycemia and hyperglycemia risk also showed a reduction in variability. Therapy changes intended to improve an individual's hypoglycemia or hyperglycemia risk often result in the reduction of one risk at the expense of another. It is important to improve glucose variability to reduce both risks or at least maintain one risk while reducing the other. Abbott Diabetes Care.

Gait Changes Vary Among Horses with Naturally Occurring Osteoarthritis Following Intra-articular Administration of Autologous Platelet Rich Plasma

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Mustajab Hussain Mirza

2016-04-01

Full Text Available Mechanisms to reduce lameness associated with osteoarthritis (OA are vital to equine health and performance. This study was designed to quantify response to autologous, intra-articular platelet-rich plasma (PRP in horses with OA. Kinetic gait analysis was performed on 12 horses with unilateral forelimb lameness and OA in the same limb before and after intra-articular anesthesia (IAA. Radiographs and kinetic data were obtained before, 6 and 16 weeks after PRP administration to same joint 4 weeks after IAA. Statistical evaluations included filtration effect on platelet concentration, relationship between kinetic variable changes after IAA versus PRP in the affected limb, and associations between response to PRP and response to IAA, platelet concentration and radiographic OA. A positive response to IAA or PRP was defined as ≥5% improvement in peak vertical force, vertical impulse or breaking impulse of the affected limb. Out of 10 horses that responded to IAA, 4 responded to PRP at both time points and 2 responded at one. Of 2 horses that did not respond to IAA, one responded to PRP at both time points. Filtration increased platelet concentration significantly. The relationship between kinetic variable alterations of the affected limb after IAA and PRP was not significant, and response to PRP was not associated with response to IAA, platelet concentration or radiographic OA. Changes in kinetic variables following IAA in joints with naturally occurring OA provide a custom standard to assess intra-articular therapy. Kinetic gait changes after intra-articular PRP are variable in horses with moderate to severe forelimb OA.

Effect of a new moisturizing lotion on immediate and cumulative skin hydration: Two randomized, intra-individual, vehicle- and comparator-controlled studies.

Science.gov (United States)

Nogueira, Alessandra; Sidou, Farzaneh; Brocard, Sylvie

2011-08-01

Moisturizers increase skin hydration and can serve as adjunctive care in dermatologic conditions such as xerosis, psoriasis vulgaris, atopic dermatitis and ichthyosis, in which dry skin is implicated. A non-irritating hydrating lotion (CDA lotion) was recently developed. We assessed the effect of CDA lotion on skin hydration in two randomized, evaluator-blind and intra-individual comparison studies. After a single application, CDA lotion induced significantly greater hydration than the non-treated control for at least 24 hours (p skin hydration up to 3 days after treatment cessation (p skin dryness score up to 7 days after treatment cessation (p hydration effects of CDA lotion were also compared to those of several currently available moisturizing products. In summary, application of CDA lotion increases skin hydration and alleviates the condition of skin dryness.

Determinants of Iran's BilateralIntra-industry Trade in Pharmaceutical Industry.

Science.gov (United States)

Aghlmand, Siamak; Rahimi, Bahlol; Farrokh-Eslamlou, Hamidreza; Nabilou, Bahram; Yusefzadeh, Hassan

2018-01-01

Among non-oil and in trade arena, drug has always been strategic importance and most government especially industrialized countries pay special attention to its production and trade issues. Thus, having a comprehensive view from economic perspective to this section is essential for suggesting intervention. This was a descriptive-analytical and panel study. In this study, gravity model is used to estimate Iran's bilateral intra-industry trade in pharmaceutical products in the 2001-2012 periods. To illustrate the extent of pharmaceutical's intra-industry trade between Iran and its major trading partners, the explanatory variables of market size, income, factor endowments, distance, cultural contributions, and similarities and also special trade arrangements have been applied. Analysis of factors affecting Iran's bilateral intra-industry trade in pharmaceutical industry showed that the average GDP and cultural similarities had a significant positive impact on Iran's bilateral IIT, while the difference in GDP has a negative and significant effect. Coefficients obtained for the geographical distance and the average ratio of total capital to the labor force is not consistent with theoretical expectations. Special trade arrangements did not have significant impact on the extent of bilateral intra-industry trade between Iran and its trading partners. The knowledge of the intra-industry trade between Iran and its trade partners make integration between the countries. Factors affecting this type of trade pattern underlie its development in trade relationship. Therefore, the findings of this study would be useful in helping to develop and implement policies for the expansion of the pharmaceutical trade.

Gait Deviation Index, Gait Profile Score and Gait Variable Score in children with spastic cerebral palsy: Intra-rater reliability and agreement across two repeated sessions.

Science.gov (United States)

Rasmussen, Helle Mätzke; Nielsen, Dennis Brandborg; Pedersen, Niels Wisbech; Overgaard, Søren; Holsgaard-Larsen, Anders

2015-07-01

The Gait Deviation Index (GDI) and Gait Profile Score (GPS) are the most used summary measures of gait in children with cerebral palsy (CP). However, the reliability and agreement of these indices have not been investigated, limiting their clinimetric quality for research and clinical practice. The aim of this study was to investigate the intra-rater reliability and agreement of summary measures of gait (GDI; GPS; and the Gait Variable Score (GVS) derived from the GPS). The intra-rater reliability and agreement were investigated across two repeated sessions in 18 children aged 5-12 years diagnosed with spastic CP. No systematic bias was observed between the sessions and no heteroscedasticity was observed in Bland-Altman plots. For the GDI and GPS, excellent reliability with intraclass correlation coefficient (ICC) values of 0.8-0.9 was found, while the GVS was found to have fair to good reliability with ICCs of 0.4-0.7. The agreement for the GDI and the logarithmically transformed GPS, in terms of the standard error of measurement as a percentage of the grand mean (SEM%) varied from 4.1 to 6.7%, whilst the smallest detectable change in percent (SDC%) ranged from 11.3 to 18.5%. For the logarithmically transformed GVS, we found a fair to large variation in SEM% from 7 to 29% and in SDC% from 18 to 81%. The GDI and GPS demonstrated excellent reliability and acceptable agreement proving that they can both be used in research and clinical practice. However, the observed large variability for some of the GVS requires cautious consideration when selecting outcome measures. Copyright © 2015 Elsevier B.V. All rights reserved.

Impact of intra- versus inter-annual snow depth variation on water relations and photosynthesis for two Great Basin Desert shrubs.

Science.gov (United States)

Loik, Michael E; Griffith, Alden B; Alpert, Holly; Concilio, Amy L; Wade, Catherine E; Martinson, Sharon J

2015-06-01

Snowfall provides the majority of soil water in certain ecosystems of North America. We tested the hypothesis that snow depth variation affects soil water content, which in turn drives water potential (Ψ) and photosynthesis, over 10 years for two widespread shrubs of the western USA. Stem Ψ (Ψ stem) and photosynthetic gas exchange [stomatal conductance to water vapor (g s), and CO2 assimilation (A)] were measured in mid-June each year from 2004 to 2013 for Artemisia tridentata var. vaseyana (Asteraceae) and Purshia tridentata (Rosaceae). Snow fences were used to create increased or decreased snow depth plots. Snow depth on +snow plots was about twice that of ambient plots in most years, and 20 % lower on -snow plots, consistent with several down-scaled climate model projections. Maximal soil water content at 40- and 100-cm depths was correlated with February snow depth. For both species, multivariate ANOVA (MANOVA) showed that Ψ stem, g s, and A were significantly affected by intra-annual variation in snow depth. Within years, MANOVA showed that only A was significantly affected by spatial snow depth treatments for A. tridentata, and Ψ stem was significantly affected by snow depth for P. tridentata. Results show that stem water relations and photosynthetic gas exchange for these two cold desert shrub species in mid-June were more affected by inter-annual variation in snow depth by comparison to within-year spatial variation in snow depth. The results highlight the potential importance of changes in inter-annual variation in snowfall for future shrub photosynthesis in the western Great Basin Desert.

Studying Basin Water Balance Variations at Inter- and Intra-annual Time Scales Based On the Budyko Hypothesis and GRACE Gravimetry Satellite Observations

Science.gov (United States)

Shen, H.

2017-12-01

Increasing intensity in global warming and anthropogenic activities has triggered significant changes over regional climates and landscapes, which, in turn, drive the basin water cycle and hydrological balance into a complex and unstable state. Budyko hypothesis is a powerful tool to characterize basin water balance and hydrological variations at long-term average scale. However, due to the absence of basin water storage change, applications of Budyko theory to the inter-annual and intra-annual time scales has been prohibited. The launch of GRACE gavimetry satellites provides a great opportunity to quantify terrestrial water storage change, which can be further introduced into the Budyko hypothesis to reveal the inter- and intra-annual response of basin water components under impacts of climate variability and/or human activities. This research targeted Hai River Basin (in China) and Murray-Darling Basin (in Australia), which have been identified with a continuous groundwater depletion trend as well as impacts by extreme climates in the past decade. This can help us to explore how annual or seasonal precipitation were redistributed to evapotranspiration and runoff via changing basin water storage. Moreover, the impacts of vegetation on annual basin water balance will be re-examined. Our results are expected to provide deep insights about the water cycle and hydrological behaviors for the targeted basins, as well as a proof for a consideration of basin water storage change into the Budyko model at inter- or intra-annual time steps.

Assessment of clinical practice guideline methodology for the treatment of knee osteoarthritis with intra-articular hyaluronic acid.

Science.gov (United States)

Altman, Roy D; Schemitsch, Emil; Bedi, Asheesh

2015-10-01

Clinical practice guidelines are of increasing importance in the decision making for the treatment of knee osteoarthritis. Inconsistent recommendations regarding the use of intra-articular hyaluronic acid for the treatment of knee osteoarthritis have led to confusion among treating physicians. Literature search to identify clinical practice guidelines that provide recommendations regarding the use of intra-articular hyaluronic acid treatment for knee osteoarthritis was conducted. Included guidelines were appraised using the AGREE II instrument. Guideline development methodologies, how the results were assessed, the recommendation formation, and work group composition were summarized. Overall, 10 clinical practice guidelines were identified that met our inclusion criteria. AGREE II domain scores were variable across the included guidelines. The methodology utilized across the guidelines was heterogeneous regarding the evidence inclusion criteria, analysis of evidence results, formulation of clinical practice recommendations, and work group composition. The recommendations provided by the guidelines for intra-articular hyaluronic acid treatment for knee osteoarthritis are highly inconsistent as a result of the variability in guideline methodology. Overall, 30% of the included guidelines recommended against the use of intra-articular hyaluronic acid in the treatment of knee osteoarthritis, while 30% deemed the treatment an appropriate intervention under certain scenarios. The remaining 40% of the guidelines provided either an uncertain recommendation or no recommendation at all, based on the high variability in reviewed evidence regarding efficacy and trial quality. There is a need for a standard "appropriate methodology" that is agreed upon for osteoarthritis clinical practice guidelines in order to prevent the development of conflicting recommendations for intra-articular hyaluronic acid treatment for knee osteoarthritis, and to assure that treating physicians who

Simulating variable source problems via post processing of individual particle tallies

International Nuclear Information System (INIS)

Bleuel, D.L.; Donahue, R.J.; Ludewigt, B.A.; Vujic, J.

2000-01-01

Monte Carlo is an extremely powerful method of simulating complex, three dimensional environments without excessive problem simplification. However, it is often time consuming to simulate models in which the source can be highly varied. Similarly difficult are optimization studies involving sources in which many input parameters are variable, such as particle energy, angle, and spatial distribution. Such studies are often approached using brute force methods or intelligent guesswork. One field in which these problems are often encountered is accelerator-driven Boron Neutron Capture Therapy (BNCT) for the treatment of cancers. Solving the reverse problem of determining the best neutron source for optimal BNCT treatment can be accomplished by separating the time-consuming particle-tracking process of a full Monte Carlo simulation from the calculation of the source weighting factors which is typically performed at the beginning of a Monte Carlo simulation. By post-processing these weighting factors on a recorded file of individual particle tally information, the effect of changing source variables can be realized in a matter of seconds, instead of requiring hours or days for additional complete simulations. By intelligent source biasing, any number of different source distributions can be calculated quickly from a single Monte Carlo simulation. The source description can be treated as variable and the effect of changing multiple interdependent source variables on the problem's solution can be determined. Though the focus of this study is on BNCT applications, this procedure may be applicable to any problem that involves a variable source

Food choice effects on herbivory: Intra-specific seagrass palatability and inter-specific macrophyte palatability in seagrass communities

Science.gov (United States)

Jiménez-Ramos, Rocío; Brun, Fernando G.; Egea, Luis G.; Vergara, Juan J.

2018-05-01

Interactions between the palatability and abundance of different food sources may influence herbivory patterns in seagrass-dominated communities. In addition, intra-specific differences in nutrient and structural quality of leaves may also alter seagrass palatability and generate different rates of consumption within these communities. We offered two temperate seagrasses species, (Cymodocea nodosa and Zostera noltei) from two different locations to look at intraspecific differences, and two other macrophytes, both of which occur at the same location as seagrasses but represent the extremes of palatability, to a generalist herbivore Paracentrotus lividus (purple sea urchin). Using feeding assays, we compared the consumption rates in individual (single plant species) and combined diets at different food availabilities. Intra-specific differences between seagrass species growing at different locations (inner and outer bay) were indeed found to significantly modify the consumption rate for one species. Structural traits such as carbon content were linked to the low consumption found in Cymodocea nodosa from the inner bay location. In addition, we found that the co-occurrence of different macrophyte species can result in preferential consumption of the more palatable macrophyte with high nutritional content and low structural defence over seagrasses, especially when P. lividus has an abundant food supply. Overall, our findings suggest that intra- and inter-specific differences in seagrass traits and the relative abundance of other macrophytes may explain the variability in patterns of herbivory found within seagrass communities.

Why is seed production so variable among individuals? A ten-year study with oaks reveals the importance of soil environment.

Science.gov (United States)

Pérez-Ramos, Ignacio M; Aponte, Cristina; García, Luis V; Padilla-Díaz, Carmen M; Marañón, Teodoro

2014-01-01

Mast-seeding species exhibit not only a large inter-annual variability in seed production but also considerable variability among individuals within the same year. However, very little is known about the causes and consequences for population dynamics of this potentially large between-individual variability. Here, we quantified seed production over ten consecutive years in two Mediterranean oak species - the deciduous Quercus canariensis and the evergreen Q. suber - that coexist in forests of southern Spain. First, we calibrated likelihood models to identify which abiotic and biotic variables best explain the magnitude (hereafter seed productivity) and temporal variation of seed production at the individual level (hereafter CVi), and infer whether reproductive effort results from the available soil resources for the plant or is primarily determined by selectively favoured strategies. Second, we explored the contribution of between-individual variability in seed production as a potential mechanism of satiation for predispersal seed predators. We found that Q. canariensis trees inhabiting moister and more fertile soils were more productive than those growing in more resource-limited sites. Regarding temporal variation, individuals of the two studied oak species inhabiting these resource-rich environments also exhibited larger values of CVi. Interestingly, we detected a satiating effect on granivorous insects at the tree level in Q. suber, which was evident in those years where between-individual variability in acorn production was higher. These findings suggest that individual seed production (both in terms of seed productivity and inter-annual variability) is strongly dependent on soil resource heterogeneity (at least for one of the two studied oak species) with potential repercussions for recruitment and population dynamics. However, other external factors (such as soil heterogeneity in pathogen abundance) or certain inherent characteristics of the tree might be

Characterizing isotopic variability of primary production and consumers in Great Plains ecosystems during protracted regional drought

Science.gov (United States)

Haveles, A. W.; Fox-Dobbs, K.; Talmadge, K. A.; Fetrow, A.; Fox, D. L.

2012-12-01

Over the last few years (2010-2012), the Great Plains of the central USA experienced protracted drought conditions, including historically severe drought during Summer, 2011. Drought severity in the region generally decreases with increasing latitude, but episodic drought is a fundamental trait of grassland ecosystems. Documenting above ground energy and nutrient flow with current drought is critical to understanding responses of grassland ecosystems in the region to predicted increased episodicity of rainfall and recurrence of drought due to anthropogenic climate change. Characterization of biogeochemical variability of modern ecosystems at the microhabitat, local landscape, and regional scales is also necessary to interpret biogeochemical records of ancient grasslands based on paleosols and fossil mammals. Here, we characterize three grassland ecosystems that span the drought gradient in the Great Plains (sites in the Texas panhandle, southwest Kansas, and northwest Nebraska). We measured δ13C and δ15N values of plants and consumers to characterize the biogeochemical variability within each ecosystem. Vegetation at each site is a mix of trees, shrubs, herbs, and cool- and warm-growing season grasses (C3 and C4, respectively). Thus, consumers have access to isotopically distinct sources of forage that vary in abundance with microhabitat (e.g., open grassland, shrub thicket, riparian woodland). Observations indicate herbivorous arthropod (grasshoppers and crickets) abundance follows drought severity, with high abundance of many species in Texas, and low abundance of few species in Nebraska. Small mammal (rodents) abundance follows the inverse pattern with 0.8%, 3.2% and 17.2% capture success in Texas, Kansas and Nebraska, respectively. The inverse abundance patterns of consumer groups may result from greater sensitivity of small mammal consumers with high metabolic needs to lower local net primary productivity and forage quality under drought conditions. As a

Assessment of metabolic phenotypic variability in children’s urine using 1H NMR spectroscopy

Science.gov (United States)

Maitre, Léa; Lau, Chung-Ho E.; Vizcaino, Esther; Robinson, Oliver; Casas, Maribel; Siskos, Alexandros P.; Want, Elizabeth J.; Athersuch, Toby; Slama, Remy; Vrijheid, Martine; Keun, Hector C.; Coen, Muireann

2017-04-01

The application of metabolic phenotyping in clinical and epidemiological studies is limited by a poor understanding of inter-individual, intra-individual and temporal variability in metabolic phenotypes. Using 1H NMR spectroscopy we characterised short-term variability in urinary metabolites measured from 20 children aged 8-9 years old. Daily spot morning, night-time and pooled (50:50 morning and night-time) urine samples across six days (18 samples per child) were analysed, and 44 metabolites quantified. Intraclass correlation coefficients (ICC) and mixed effect models were applied to assess the reproducibility and biological variance of metabolic phenotypes. Excellent analytical reproducibility and precision was demonstrated for the 1H NMR spectroscopic platform (median CV 7.2%). Pooled samples captured the best inter-individual variability with an ICC of 0.40 (median). Trimethylamine, N-acetyl neuraminic acid, 3-hydroxyisobutyrate, 3-hydroxybutyrate/3-aminoisobutyrate, tyrosine, valine and 3-hydroxyisovalerate exhibited the highest stability with over 50% of variance specific to the child. The pooled sample was shown to capture the most inter-individual variance in the metabolic phenotype, which is of importance for molecular epidemiology study design. A substantial proportion of the variation in the urinary metabolome of children is specific to the individual, underlining the potential of such data to inform clinical and exposome studies conducted early in life.

Intra-oral pressure-based voicing control of electrolaryngeal speech with intra-oral vibrator.

Science.gov (United States)

Takahashi, Hirokazu; Nakao, Masayuki; Kikuchi, Yataro; Kaga, Kimitaka

2008-07-01

In normal speech, coordinated activities of intrinsic laryngeal muscles suspend a glottal sound at utterance of voiceless consonants, automatically realizing a voicing control. In electrolaryngeal speech, however, the lack of voicing control is one of the causes of unclear voice, voiceless consonants tending to be misheard as the corresponding voiced consonants. In the present work, we developed an intra-oral vibrator with an intra-oral pressure sensor that detected utterance of voiceless phonemes during the intra-oral electrolaryngeal speech, and demonstrated that an intra-oral pressure-based voicing control could improve the intelligibility of the speech. The test voices were obtained from one electrolaryngeal speaker and one normal speaker. We first investigated on the speech analysis software how a voice onset time (VOT) and first formant (F1) transition of the test consonant-vowel syllables contributed to voiceless/voiced contrasts, and developed an adequate voicing control strategy. We then compared the intelligibility of consonant-vowel syllables among the intra-oral electrolaryngeal speech with and without online voicing control. The increase of intra-oral pressure, typically with a peak ranging from 10 to 50 gf/cm2, could reliably identify utterance of voiceless consonants. The speech analysis and intelligibility test then demonstrated that a short VOT caused the misidentification of the voiced consonants due to a clear F1 transition. Finally, taking these results together, the online voicing control, which suspended the prosthetic tone while the intra-oral pressure exceeded 2.5 gf/cm2 and during the 35 milliseconds that followed, proved efficient to improve the voiceless/voiced contrast.

Glomerular epithelial foot processes in normal man and rats. Distribution of true width and its intra- and inter-individual variation.

Science.gov (United States)

Gundersen, H J; Seefeldt, T; Osterby, R

1980-01-01

The width of individual glomerular epithelial foot processes appears very different on electron micrographs. A method for obtainining distributions of the true width of foot processes from that of their apparent width on electron micrographs has been developed based on geometric probability theory pertaining to a specific geometric model. Analyses of foot process width in humans and rats show a remarkable interindividual invariance implying rigid control and therefore great biological significance of foot process width or a derivative thereof. The very low inter-individual variation of the true width, shown in the present paper, makes it possible to demonstrate slight changes in rather small groups of patients or experimental animals.

Preliminary evaluations related to the ranges of hematological and biochemical variables in hospitalized patients with stroke

Directory of Open Access Journals (Sweden)

Ahmad Chitsaz

2013-01-01

Conclusions: Any considerable alter in patients′ biochemical and hematological figures (BS, Hgb, Plt and Lymph may necessitate further attention related to inter- and intra-individual variability in clinical supervision and drug′s assortment. Therefore, success in treatment could be achieved by the close management of clinical, biochemical, hematological, and pharmacological manifestation. To reduce disability, mortality, and morbidity in Iranian stroke population further clinical studies are needed to correlate drugs and laboratory markers to associated clinical events in order.

Using stable isotopes to investigate individual diet specialization in California sea otters (Enhydra lutris nereis)

Science.gov (United States)

Newsome, S.D.; Tinker, M.T.; Monson, Daniel H.; Oftedal, O.T.; Ralls, K.; Staedler, M.M.; Fogel, M.L.; Estes, J.A.

2009-01-01

Differences in diet composition among conspecifics (dietary specialization) have been documented across a broad range of taxonomic groups and habitats, and such variation at the individual level is increasingly recognized as an important component of diversity in trophic interactions. Accurate identification of individual dietary specialization, however, requires longitudinal dietary records that are labor-intensive and cost-prohibitive to obtain for many species. Here we explore the use of stable isotopes (δ13C and δ15N) as a promising technique for detecting and quantifying patterns of individual dietary specialization. Southern sea otters (Enhydra lutris nereis) offer a unique opportunity for testing this approach because (1) they consume a wide variety of prey that span multiple trophic levels, habitats, and ecologically defined functional groups; and (2) individual diet specialization can be validated with existing observational data. We analyzed the isotopic composition of sea otter vibrissae (n = 31) in order to characterize inter- and intra-individual variation in sea otter diets at Monterey Bay, California, USA. At the population level, sea otters showed substantial variation in both δ13C and δ15N values, occupying nearly all of the “isotopic space” created by the diversity of isotopic signatures of potential prey taxa. Most of the variation in sea otter vibrissae was accounted for by differences between individuals, with much less contributed by within-individual variation. A majority of sea otters (∼80%) showed relatively little temporal variability in isotopic composition, suggesting that the proportional composition of most individuals' diets is relatively constant over time; a few individuals (∼20%) exhibited a high degree of intra-vibrissa isotopic variability, suggesting seasonal shifts in diet composition. These results and our interpretation of them were supported by long-term observational data on the diets of radio-tagged sea otters

Intra and Inter-Individual Differences in Social Intelligence of Portuguese Students

Directory of Open Access Journals (Sweden)

Joana Carneiro Pinto

2015-08-01

Full Text Available Social intelligence is a favorable condition for career decision-making and development. The social intelligence indices of Portuguese students in school years prior to a career transition are characterized and intra and interindividual differences are analyzed. Participants were 1095 students (552, 50.4% women with a mean age of 14.78 years (SD = 1.86, in the 8th (542, 49.5%, 10th (295, 26.9% and 11th (258, 23.6% grades. The Cognitive Test of Social Intelligence (PCIS was administered at two moments, six months apart. Results indicate that the 8th grade obtained higher average scores in Problem Solving, Motivation and Self-confidence (time 1, while the 10th grade obtained better results in Problem Solving, Motivation and Familiarity (time 2. Between the assessment moments, all school years register an increase in Problem Solving and Self-confidence in social situations. These results constitute favorable psychological conditions for the promotion of ethical questioning in career guidance interventions.

Motion or activity: their role in intra- and inter-subject variation in fMRI

DEFF Research Database (Denmark)

Lund, Torben E; Nørgaard, Minna D; Rostrup, Egill

2005-01-01

MRI to pre-surgical planning because of a higher requirement for intra-subject precision. The purpose of this study was to investigate the impact of residual movement artefacts on intra-subject and inter-subject variability in the observed fMRI activation. Ten subjects were examined using three different...... word-generation tasks. Two of the subjects were examined 10 times on 10 different days using the same paradigms. We systematically investigated one approach of correcting for residual movement effects: the inclusion of regressors describing movement-related effects in the design matrix of a General...

Manipulating the wavelength-drift of a Tm laser for resonance enhancement in an intra-cavity pumped Ho laser.

Science.gov (United States)

Huang, Haizhou; Huang, Jianhong; Liu, Huagang; Li, Jinhui; Lin, Zixiong; Ge, Yan; Dai, Shutao; Deng, Jing; Lin, Wenxiong

2018-03-05

We demonstrate an enhancement mechanism and thermal model for intra-cavity pumped lasers, where resonance enhancement in intra-cavity pumped Ho laser was achieved by manipulating the wavelength-drift nature of the Tm laser for the first time. Optical conversion efficiency of 37.5% from an absorbed 785 nm diode laser to a Ho laser was obtained with a maximum output power of 7.51 W at 2122 nm, which is comparable to the conversion efficiency in 1.9 μm LD pumped Ho lasers. Meanwhile, more severe thermal effects in the Ho-doped gain medium than the Tm-doped one at high power operation were verified based on the built thermal model. This work benefits the design or evaluation of intra-cavity pumped lasers, and the resonance enhancement originated from the difference in reabsorption loss between stark levels at the lasing manifolds of quasi-three-level rare-earth ions has great interest to improve the existing intra-cavity pumped lasers or explore novel lasers.

The use of ultrasound to diagnose hepatic steatosis in type 2 diabetes: Intra- and interobserver variability and comparison with magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Williamson, R.M.; Perry, E.; Glancy, S.; Marshall, I.; Gray, C.; Nee, L.D.; Hayes, P.C.; Forbes, S.; Frier, B.M.; Johnston, G.I.; Lee, A.J.; Reynolds, R.M.; Price, J.F.; Strachan, M.W.J.

2011-01-01

Aim: To compare ultrasound gradings of steatosis with fat fraction (FF) on magnetic resonance spectroscopy (MRS; the non-invasive reference standard for quantification of hepatic steatosis), and evaluate inter- and intraobserver variability in the ultrasound gradings. Materials and methods: Triple grading of hepatic ultrasound examination was performed by three independent graders on 131 people with type 2 diabetes. The stored images of 60 of these individuals were assessed twice by each grader on separate occasions. Fifty-eight patients were pre-selected on the basis of ultrasound grading (normal, indeterminate/mild steatosis, or severe steatosis) to undergo 1 H-MRS. The sensitivity and specificity of the ultrasound gradings were determined with reference to MRS data, using two cut-offs of FF to define steatosis, ≥9% and ≥6.1%. Results: Median (intraquartile range) MRS FF (%) in the participants graded on ultrasound as normal, indeterminate/mild steatosis, and severe steatosis were 4.2 (1.2-5.7), 4.1 (3.1-8.5) and 19.4 (12.9-27.5), respectively. Using a liver FF of ≥6.1% on MRS to denote hepatic steatosis, the unadjusted sensitivity and specificity of ultrasound gradings (severe versus other grades of steatosis) were 71 and 100%, respectively. Interobserver agreement within one grade was observed in 79% of cases. Exact intraobserver agreement ranged from 62 to 87%. Conclusion: Hepatic ultrasound provided a good measure of the presence of significant hepatic steatosis with good intra- and interobserver agreement. The grading of a mildly steatotic liver was less secure and, in particular, there was considerable overlap in hepatic FF with those who had a normal liver on ultrasound.

The use of ultrasound to diagnose hepatic steatosis in type 2 diabetes: Intra- and interobserver variability and comparison with magnetic resonance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Williamson, R.M., E-mail: rachel_m_williamson@hotmail.co [Metabolic Unit, Western General Hospital, Edinburgh (United Kingdom); Perry, E.; Glancy, S. [Department of Radiology, Western General Hospital, Edinburgh (United Kingdom); Marshall, I. [Scottish Funding Council Brain Imaging Research Centre, Western General Hospital, Edinburgh (United Kingdom); Gray, C. [Wellcome Trust Clinical Research Facility, Western General Hospital, Edinburgh (United Kingdom); Nee, L.D. [Department of Radiology, Western General Hospital, Edinburgh (United Kingdom); Hayes, P.C. [Department of Hepatology, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); Forbes, S. [Endocrinology Unit, University of Edinburgh, Queen' s Medical Research Institute, Edinburgh (United Kingdom); Frier, B.M. [Department of Diabetes, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); Johnston, G.I. [Pfizer Global R and D, Sandwich, Kent (United Kingdom); Lee, A.J. [Centre of Academic Primary Care, University of Aberdeen, Aberdeen (United Kingdom); Reynolds, R.M. [Endocrinology Unit, University of Edinburgh, Queen' s Medical Research Institute, Edinburgh (United Kingdom); Price, J.F. [Centre for Population Health Sciences, University of Edinburgh, Queen' s Medical Research Institute, Edinburgh (United Kingdom); Strachan, M.W.J. [Metabolic Unit, Western General Hospital, Edinburgh (United Kingdom)

2011-05-15

Aim: To compare ultrasound gradings of steatosis with fat fraction (FF) on magnetic resonance spectroscopy (MRS; the non-invasive reference standard for quantification of hepatic steatosis), and evaluate inter- and intraobserver variability in the ultrasound gradings. Materials and methods: Triple grading of hepatic ultrasound examination was performed by three independent graders on 131 people with type 2 diabetes. The stored images of 60 of these individuals were assessed twice by each grader on separate occasions. Fifty-eight patients were pre-selected on the basis of ultrasound grading (normal, indeterminate/mild steatosis, or severe steatosis) to undergo {sup 1}H-MRS. The sensitivity and specificity of the ultrasound gradings were determined with reference to MRS data, using two cut-offs of FF to define steatosis, {>=}9% and {>=}6.1%. Results: Median (intraquartile range) MRS FF (%) in the participants graded on ultrasound as normal, indeterminate/mild steatosis, and severe steatosis were 4.2 (1.2-5.7), 4.1 (3.1-8.5) and 19.4 (12.9-27.5), respectively. Using a liver FF of {>=}6.1% on MRS to denote hepatic steatosis, the unadjusted sensitivity and specificity of ultrasound gradings (severe versus other grades of steatosis) were 71 and 100%, respectively. Interobserver agreement within one grade was observed in 79% of cases. Exact intraobserver agreement ranged from 62 to 87%. Conclusion: Hepatic ultrasound provided a good measure of the presence of significant hepatic steatosis with good intra- and interobserver agreement. The grading of a mildly steatotic liver was less secure and, in particular, there was considerable overlap in hepatic FF with those who had a normal liver on ultrasound.

An investigation into the causes of unexpected intra-operative transoesophageal echocardiography findings.

Science.gov (United States)

Skinner, H J; Mahmoud, A; Uddin, A; Mathew, T

2012-04-01

There is uncertainty regarding echocardiography before cardiac surgery, especially with regard to timing and disease progression as well as potential errors. We investigated the causes of unexpected intra-operative transoesophageal echocardiography findings by performing a 33-month audit. We found that there were 50/797 (6%) unexpected findings that led to an alteration in surgical strategy in 34 (4%) patients. Of the unexpected findings, 25 (50%) were unrelated to pre-operative pathology. After reviewing pre-operative studies and reports, unexpected findings were found to be due to: reporting errors in 20 patients (44%); limitations in transthoracic compared to transoesophageal echocardiography in 14 patients (30%); disease progression in 10 patients (22%); and inter-observer variability in two patients (4%). We identified six reports out of 797 (0.8%) that contained potentially serious errors. Surgical management changed in 18/20 (90%) patients in whom the unexpected change was due to reporting error, compared to 16/30 (53%) patients whose pre-operative echocardiogram was correctly reported (p = 0.006). Our study suggests that pre-operative echocardiography reporting errors are common and important. Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.

Variability of skin autofluorescence measurement over 6 and 12 weeks and the influence of benfotiamine treatment.

Science.gov (United States)

Stirban, Alin; Pop, Alexandra; Fischer, Annelie; Heckermann, Sascha; Tschoepe, Diethelm

2013-09-01

Measurements of skin autofluorescence (SAF) allow for a simple and noninvasive quantification of tissue advanced glycation end-products (AGEs), a marker linked to the risk of diabetes complications. The aim of this study was to test the repeatability of SAF over 6 and 12 weeks and to test whether benfotiamine, a thiamine prodrug suggested to reduce AGEs formation under hyperglycemic conditions, is able to attenuate SAF when administered over 6 weeks. In a double-blind, placebo-controlled, randomized, crossover study, 22 patients with type 2 diabetes mellitus (T2DM) received 900 mg/day benfotiamine or placebo for 6 weeks (washout period of 6 weeks between). At the beginning and at the end of each treatment period, SAF was assessed in the fasting state, as well as 2, 4, and 6 h following a mixed test meal. The respective intra-individual and inter-individual variability of fasting SAF was 6.9% and 24.5% within 6 weeks and 10.9% and 23.1% within 12 weeks. The respective variability calculated for triplicate comparisons was 9.9% and 27.7%. A short-term therapy with benfotiamine did not influence SAF significantly, nor did we find a significant postprandial SAF increase. In patients with T2DM, repeated, timely spaced SAF measurements have an intra-subject variability of below 11%. Using these data, sample sizes were calculated for interventional studies aiming at reducing SAF. Benfotiamine treatment for 6 weeks did not significantly influence SAF; for this, a longer-term therapy is probably needed.

What is the optimal management of an intra-operative air leak in a colorectal anastomosis?

Science.gov (United States)

Mitchem, J B; Stafford, C; Francone, T D; Roberts, P L; Schoetz, D J; Marcello, P W; Ricciardi, R

2018-02-01

An airtight anastomosis on intra-operative leak testing has been previously demonstrated to be associated with a lower risk of clinically significant postoperative anastomotic leak following left-sided colorectal anastomosis. However, to date, there is no consistently agreed upon method for management of an intra-operative anastomotic leak. Therefore, we powered a noninferiority study to determine whether suture repair alone was an appropriate strategy for the management of an intra-operative air leak. This is a retrospective cohort analysis of prospectively collected data from a tertiary care referral centre. We included all consecutive patients with left-sided colorectal or ileorectal anastomoses and evidence of air leak during intra-operative leak testing. Patients were excluded if proximal diversion was planned preoperatively, a pre-existing proximal diversion was present at the time of surgery or an anastomosis was ultimately unable to be completed. The primary outcome measure was clinically significant anastomotic leak, as defined by the Surgical Infection Study Group at 30 days. From a sample of 2360 patients, 119 had an intra-operative air leak during leak testing. Sixty-eight patients underwent suture repair alone and 51 underwent proximal diversion or anastomotic reconstruction. The clinically significant leak rate was 9% (6/68; 95% CI: 2-15%) in the suture repair alone arm and 0% (0/51) in the diversion or reconstruction arm. Suture repair alone does not meet the criteria for noninferiority for the management of intra-operative air leak during left-sided colorectal anastomosis. Further repair of intra-operative air leak by suture repair alone should be reconsidered given these findings. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

Influence of short-term blood pressure variability on blood pressure determinations

NARCIS (Netherlands)

Bos, W. J.; van Goudoever, J.; van Montfrans, G. A.; Wesseling, K. H.

1992-01-01

To evaluate the effect of blood pressure variability on Riva Rocci Korotkoff blood pressure determinations, we studied the intra-arterial pressure during Riva Rocci Korotkoff determinations in 25 patients. In 50 measurements with a cuff deflation rate of 2.5 mm Hg/sec, the systolic intra-arterial

Disproportionality in Special Education: Effects of Individual and School Variables on Disability Risk

Science.gov (United States)

Sullivan, Amanda L.; Bal, Aydin

2013-01-01

We examined the risk of disability identification associated with individual and school variables. The sample included 18,000 students in 39 schools of an urban K-12 school system. Descriptive analysis showed racial minority risk varied across 7 disability categories, with males and students from low-income backgrounds at highest risk in most…

Variability of individual genetic load: consequences for the detection of inbreeding depression.

Science.gov (United States)

Restoux, Gwendal; Huot de Longchamp, Priscille; Fady, Bruno; Klein, Etienne K

2012-03-01

Inbreeding depression is a key factor affecting the persistence of natural populations, particularly when they are fragmented. In species with mixed mating systems, inbreeding depression can be estimated at the population level by regressing the average progeny fitness by the selfing rate of their mothers. We applied this method using simulated populations to investigate how population genetic parameters can affect the detection power of inbreeding depression. We simulated individual selfing rates and genetic loads from which we computed fitness values. The regression method yielded high statistical power, inbreeding depression being detected as significant (5 % level) in 92 % of the simulations. High individual variation in selfing rate and high mean genetic load led to better detection of inbreeding depression while high among-individual variation in genetic load made it more difficult to detect inbreeding depression. For a constant sampling effort, increasing the number of progenies while decreasing the number of individuals per progeny enhanced the detection power of inbreeding depression. We discuss the implication of among-mother variability of genetic load and selfing rate on inbreeding depression studies.

Inter and intra-observer reliability in assessment of the position of the lateral sesamoid in determining the severity of hallux valgus.

Science.gov (United States)

Panchani, Sunil; Reading, Jonathan; Mehta, Jaysheel

2016-06-01

The position of the lateral sesamoid on standard dorso-plantar weight bearing radiographs, with respect to the lateral cortex of the first metatarsal, has been shown to correlate well with the degree of the hallux valgus angle. This study aimed to assess the inter- and intra-observer error of this new classification system. Five orthopaedic consultants and five trainee orthopaedic surgeons were recruited to assess and document the degree of displacement of the lateral sesamoid on 144 weight-bearing dorso-plantar radiographs on two separate occasions. The severity of hallux valgus was defined as normal (0%), mild (≤50%), moderate (51-≤99%) or severe (≥100%) depending on the percentage displacement of the lateral sesamoid body from the lateral cortical border of the first metatarsal. Consultant intra-observer variability showed good agreement between repeated assessment of the radiographs (mean Kappa=0.75). Intra-observer variability for trainee orthopaedic surgeons also showed good agreement with a mean Kappa=0.73. Intraclass correlations for consultants and trainee surgeons was also high. The new classification system of assessing the severity of hallux valgus shows high inter- and intra-observer variability with good agreement and reproducibility between surgeons of consultant and trainee grades. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of weather and climate variables on the basal area growth of individual shortleaf pine trees

Science.gov (United States)

Pradip Saud; Thomas B. Lynch; Duncan S. Wilson; John Stewart; James M. Guldin; Bob Heinemann; Randy Holeman; Dennis Wilson; Keith Anderson

2015-01-01

An individual-tree basal area growth model previously developed for even-aged naturally occurring shortleaf pine trees (Pinus echinata Mill.) in western Arkansas and southeastern Oklahoma did not include weather variables. Individual-tree growth and yield modeling of shortleaf pine has been carried out using the remeasurements of over 200 plots...

Spiritual well-being in individuals with fibromyalgia syndrome: relationships with symptom pattern variability, uncertainty, and psychosocial adaptation.

Science.gov (United States)

Anema, Cheryl; Johnson, Mary; Zeller, Janice M; Fogg, Louis; Zetterlund, Joan

2009-01-01

This study examined relationships among symptom pattern variability, uncertainty, spiritual well-being, and psychosocial adaptation in individuals with fibromyalgia syndrome (FMS). A survey design was used with 58 individuals with FMS. The Fibromyalgia Symptom Pattern Questionnaire, Mishel Uncertainty in Illness Scale--Community Form, Spiritual Well-Being Scale, and Psychosocial Adjustment to Illness Scale-Self Report were used to collect data. Positive relationships were found between symptom pattern variability and uncertainty and between uncertainty and poor psychosocial adaptation; spiritual well-being moderated the relationship between uncertainty and psychosocial adaptation. A positive sense of well-being aided adaptation to symptoms and uncertainties of FMS. Spiritual well-being had a greater effect on the relationship between symptom pattern variability and uncertainty than expected.

A psychology of religious plurality: from intra-religious dialogue to intra-psychic reality.

Science.gov (United States)

Kramp, Joseph M

2012-09-01

Panikkar's (The intra-religious dialogue, 1978) classic, re-issued by Paulist Press in 1999, grapples with the theological challenges in the disciplines of comparative theology and the theology of religions through what he terms, "intra-religious dialogue." In this psychology of religious plurality, I use works from a variety of disciplines to highlight the achievements of Panikkar's intra-religious dialogue, as well as to critique his work in the hope of finding categories of understanding that can be profitably used to face the inter-personal crises of the contemporary world, namely religious terrorism.

Determinants of Iran’s Bilateral Intra-industry Trade in Pharmaceutical Industry

Science.gov (United States)

Aghlmand, Siamak; Rahimi, Bahlol; Farrokh-Eslamlou, Hamidreza; Nabilou, Bahram; Yusefzadeh, Hassan

2018-01-01

Among non-oil and in trade arena, drug has always been strategic importance and most government especially industrialized countries pay special attention to its production and trade issues. Thus, having a comprehensive view from economic perspective to this section is essential for suggesting intervention. This was a descriptive-analytical and panel study. In this study, gravity model is used to estimate Iran’s bilateral intra-industry trade in pharmaceutical products in the 2001-2012 periods. To illustrate the extent of pharmaceutical’s intra-industry trade between Iran and its major trading partners, the explanatory variables of market size, income, factor endowments, distance, cultural contributions, and similarities and also special trade arrangements have been applied. Analysis of factors affecting Iran’s bilateral intra-industry trade in pharmaceutical industry showed that the average GDP and cultural similarities had a significant positive impact on Iran’s bilateral IIT, while the difference in GDP has a negative and significant effect. Coefficients obtained for the geographical distance and the average ratio of total capital to the labor force is not consistent with theoretical expectations. Special trade arrangements did not have significant impact on the extent of bilateral intra-industry trade between Iran and its trading partners. The knowledge of the intra-industry trade between Iran and its trade partners make integration between the countries. Factors affecting this type of trade pattern underlie its development in trade relationship. Therefore, the findings of this study would be useful in helping to develop and implement policies for the expansion of the pharmaceutical trade. PMID:29881438

Individual and population-level impacts of an emerging poxvirus disease in a wild population of great tits.

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Shelly Lachish

Full Text Available Emerging infectious diseases of wildlife can have severe effects on host populations and constitute a pressing problem for biodiversity conservation. Paridae pox is an unusually severe form of avipoxvirus infection that has recently been identified as an emerging infectious disease particularly affecting an abundant songbird, the great tit (Parus major, in Great Britain. In this study, we study the invasion and establishment of Paridae pox in a long-term monitored population of wild great tits to (i quantify the impact of this novel pathogen on host fitness and (ii determine the potential threat it poses to population persistence. We show that Paridae pox significantly reduces the reproductive output of great tits by reducing the ability of parents to fledge young successfully and rear those young to independence. Our results also suggested that pathogen transmission from diseased parents to their offspring was possible, and that disease entails severe mortality costs for affected chicks. Application of multistate mark-recapture modelling showed that Paridae pox causes significant reductions to host survival, with particularly large effects observed for juvenile survival. Using an age-structured population model, we demonstrate that Paridae pox has the potential to reduce population growth rate, primarily through negative impacts on host survival rates. However, at currently observed prevalence, significant disease-induced population decline seems unlikely, although pox prevalence may be underestimated if capture probability of diseased individuals is low. Despite this, because pox-affected model populations exhibited lower average growth rates, this emerging infectious disease has the potential to reduce the resilience of populations to other environmental factors that reduce population size.

The intra-day dynamics of affect, self-esteem, tiredness, and suicidality in Major Depression.

Science.gov (United States)

Crowe, Eimear; Daly, Michael; Delaney, Liam; Carroll, Susan; Malone, Kevin M

2018-02-21

Despite growing interest in the temporal dynamics of Major Depressive Disorder (MDD), we know little about the intra-day fluctuations of key symptom constructs. In a study of momentary experience, the Experience Sampling Method captured the within-day dynamics of negative affect, positive affect, self-esteem, passive suicidality, and tiredness across clinical MDD (N= 31) and healthy control groups (N= 33). Ten symptom measures were taken per day over 6 days (N= 2231 observations). Daily dynamics were modeled via intra-day time-trends, variability, and instability in symptoms. MDD participants showed significantly increased variability and instability in negative affect, positive affect, self-esteem, and suicidality. Significantly different time-trends were found in positive affect (increased diurnal variation and an inverted U-shaped pattern in MDD, compared to a positive linear trend in controls) and tiredness (decreased diurnal variation in MDD). In the MDD group only, passive suicidality displayed a negative linear trend and self-esteem displayed a quadratic inverted U trend. MDD and control participants thus showed distinct dynamic profiles in all symptoms measured. As well as the overall severity of symptoms, intra-day dynamics appear to define the experience of MDD symptoms. Copyright © 2018 Elsevier B.V. All rights reserved.

Intra-abdominal fat accumulation is a hypertension risk factor in young adulthood: A cross-sectional study.

Science.gov (United States)

Takeoka, Atsushi; Tayama, Jun; Yamasaki, Hironori; Kobayashi, Masakazu; Ogawa, Sayaka; Saigo, Tatsuo; Kawano, Hiroaki; Abiru, Norio; Hayashida, Masaki; Maeda, Takahiro; Shirabe, Susumu

2016-11-01

Accumulation of intra-abdominal fat is related to hypertension. Despite this, a relationship between hypertension and intra-abdominal fat in young adulthood is not clear. In this study, we verify whether intra-abdominal fat accumulation increases a hypertension risk in young adult subjects.In a cross-sectional study, intra-abdominal fat area was measured using a dual bioelectrical impedance analysis instrument in 697 university students (20.3 ± 0.7 years, 425 men). Blood pressure and anthropometric factors were measured. Lifestyle variables including smoking, drinking, physical activity, and eating behavior were assessed with questionnaire. High blood pressure risk (systolic blood pressure ≥130 mm Hg and/or diastolic blood pressure ≥85 mm Hg) with increasing intra-abdominal fat area was evaluated.Participants were divided into 5 groups according to their intra-abdominal fat area (≤24.9, 25-49.9, 50-74.9, 75-99.9, and ≥100 cm). As compared with the values of the smallest intra-abdominal fat area group, the crude and lifestyle-adjusted odds ratios (ORs) were elevated in larger intra-abdominal fat area groups [OR 1.31, 95% confidence interval (CI) 0.66-2.80; OR 3.38, 95% CI 1.60-7.57; OR 7.71, 95% CI 2.75-22.22; OR 18.74, 95% CI 3.93-105.64, respectively). The risk increase was observed only in men.Intra-abdominal fat accumulation is related to high blood pressure in men around 20 years of age. These results indicate the importance of evaluation and reduction of intra-abdominal fat to prevent hypertension.

Individual testosterone decline and future mortality risk in men.

Science.gov (United States)

Holmboe, Stine A; Skakkebæk, Niels E; Juul, Anders; Scheike, Thomas; Jensen, Tina K; Linneberg, Allan; Thuesen, Betina H; Andersson, Anna-Maria

2018-01-01

Male aging is characterized by a decline in testosterone (TS) levels with a substantial variability between subjects. However, it is unclear whether differences in age-related changes in TS are associated with general health. We investigated associations between mortality and intra-individual changes in serum levels of total TS, SHBG, free TS and LH during a ten-year period with up to 18 years of registry follow-up. 1167 men aged 30-60 years participating in the Danish Monitoring Trends and Determinants of Cardiovascular Disease (MONICA1) study and who had a follow-up examination ten years later (MONICA10) were included. From MONICA10, the men were followed up to 18 years (mean: 15.2 years) based on the information from national mortality registries via their unique personal ID numbers. Cox proportional hazard models were used to investigate the association between intra-individual hormone changes and all-cause, CVD and cancer mortalities. A total of 421 men (36.1%) died during the follow-up period. Men with most pronounced decline in total TS (mortality risk compared to men within the 10th to 90th percentile (hazard ratio (HR): 1.60; 95% confidence interval (CI): 1.08-2.36). No consistent associations were seen in cause-specific mortality analyses. Our study showed that higher mortality rates were seen among the men who had the most pronounced age-related decline in TS, independent of their baseline TS levels. © 2018 European Society of Endocrinology.

Influence of intra-tumoral heterogeneity on the evaluation of BCL2, E-cadherin, EGFR, EMMPRIN, and Ki-67 expression in tissue microarrays from breast cancer.

Science.gov (United States)

Tramm, Trine; Kyndi, Marianne; Sørensen, Flemming B; Overgaard, Jens; Alsner, Jan

2018-01-01

The influence of intra-tumoral heterogeneity on the evaluation of immunohistochemical (IHC) biomarker expression may affect the analytical validity of new biomarkers substantially and hence compromise the clinical utility. The aim of this study was to examine the influence of intra-tumoral heterogeneity as well as inter-observer variability on the evaluation of various IHC markers with potential prognostic impact in breast cancer (BCL2, E-cadherin, EGFR, EMMPRIN and Ki-67). From each of 27 breast cancer patients, two tumor-containing paraffin blocks were chosen. Intra-tumoral heterogeneity was evaluated (1) within a single tumor-containing paraffin block ('intra-block agreement') by comparing information from a central, a peripheral tissue microarray (TMA) core and a whole slide section (WS), (2) between two different tumor-containing blocks from the same primary tumor ('inter-block agreement') by comparing information from TMA cores (central/peripheral) and WS. IHC markers on WS and TMA cores were evaluated by two observers independently, and agreements were estimated by Kappa statistics. For BCL2, E-cadherin and EGFR, an almost perfect intra- and inter-block agreement was found. EMMPRIN and Ki-67 showed a more heterogeneous expression with moderate to substantial intra-block agreements. For both stainings, there was a moderate inter-block agreement that improved slightly for EMMPRIN, when using WS instead of TMA cores. Inter-observer agreements were found to be almost perfect for BCL2, E-cadherin and EGFR (WS: κ > 0.82, TMAs: κ > 0.90), substantial for EMMPRIN (κ > 0.63), but only fair to moderate for Ki-67 (WS: κ = 0.54, TMAs: κ = 0.33). BCL2, E-cadherin and EGFR were found to be homogeneously expressed, whereas EMMPRIN and Ki-67 showed a more pronounced degree of intra-tumoral heterogeneity. The results emphasize the importance of securing the analytical validity of new biomarkers by examining the intra-tumoral heterogeneity of

Intra-abdominal pressure during swimming.

Science.gov (United States)

Moriyama, S; Ogita, F; Huang, Z; Kurobe, K; Nagira, A; Tanaka, T; Takahashi, H; Hirano, Y

2014-02-01

The present study aimed to determine the intra-abdominal pressure during front crawl swimming at different velocities in competitive swimmers and to clarify the relationships between stroke indices and changes in intra-abdominal pressure. The subjects were 7 highly trained competitive collegiate male swimmers. Intra-abdominal pressure was measured during front crawl swimming at 1.0, 1.2 and 1.4 m · s(-1) and during the Valsalva maneuver. Intra-abdominal pressure was taken as the difference between minimum and maximum values, and the mean of 6 stable front crawl stroke cycles was used. Stroke rate and stroke length were also measured as stroke indices. There were significant differences in stroke rate among all velocities (P pressure and stroke rate or stroke length (P pressure and stroke indices when controlling for swimming velocity. These findings do not appear to support the effectiveness of trunk training performed by competitive swimmers aimed at increasing intra-abdominal pressure. © Georg Thieme Verlag KG Stuttgart · New York.

STUDYING THE EFFECTS OF SPORTING HABITS ON THE SELF-ESTEEM OF DISABLED INDIVIDUALS

OpenAIRE

Erdoğan; Bülent; Gökhan; Serkan Tevabil

2014-01-01

It is considered that whether disabled individuals have low or high self- esteem Serkan T. AKA3 affects their interactions with the other individuals and how they cope with the challenges they come across in a society. Therefore, it is great significance to study the factors that are effective in boosting the self-esteem of such individuals. Bülent TATLISU2 The purpose of this study is to investigate the effects of sporting habits and different variables on the self-esteem level of ...

Relative effects of precipitation variability and warming on tallgrass prairie ecosystem function

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P. A. Fay

2011-10-01

Full Text Available Precipitation and temperature drive many aspects of terrestrial ecosystem function. Climate change scenarios predict increasing precipitation variability and temperature, and long term experiments are required to evaluate the ecosystem consequences of interannual climate variation, increased growing season (intra-annual rainfall variability, and warming. We present results from an experiment applying increased growing season rainfall variability and year round warming in native tallgrass prairie. During ten years of study, total growing season rainfall varied 2-fold, and we found ~50–200% interannual variability in plant growth and aboveground net primary productivity (ANPP, leaf carbon assimilation (A_CO2, and soil CO₂ efflux (J_CO2 despite only ~40% variation in mean volumetric soil water content (0–15 cm, Θ₁₅. Interannual variation in soil moisture was thus amplified in most measures of ecosystem response. Differences between years in Θ₁₅ explained the greatest portion (14–52% of the variation in these processes. Experimentally increased intra-annual season rainfall variability doubled the amplitude of intra-annual soil moisture variation and reduced Θ₁₅ by 15%, causing most ecosystem processes to decrease 8–40% in some or all years with increased rainfall variability compared to ambient rainfall timing, suggesting reduced ecosystem rainfall use efficiency. Warming treatments increased soil temperature at 5 cm depth, particularly during spring, fall, and winter. Warming advanced canopy green up in spring, increased winter J_CO2, and reduced summer J_CO2 and forb ANPP, suggesting that the effects of warming differed in cooler versus warmer parts of the year. We conclude that (1 major ecosystem processes in this grassland may be substantially altered by predicted changes in

Intra-puparial development of the females of Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae Desenvolvimento intra-pupal de fêmeas de Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae

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José Roberto Pujol-Luz

2012-09-01

Full Text Available Intra-puparial development of the females of Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae. The chronology and morphological changes that take place during intra-puparial development of Chrysomya albiceps is described based on 254 specimens reared in the laboratory. Larvae were obtained from the eggs laid by a single female. The pre-pupae were separated according to the reduction of larval length and the degree of pigmentation and sclerotization of the cuticle. After pupation, 10 individuals were fixed in Carnoy's solution and preserved in 70% ethanol, 10 individuals were fixed every 3 hours up to complete the first 24 hours (n = 80, the remaining individuals were fixed every six hours up to the 90th hour (n = 110 when 54 females emerged. The pupae were immersed in 5% formic acid for 48 hours and maintained in 70% ethanol, and then dissected and analyzed. C. albiceps shows four intra-puparial stages, each of which were described and compared with those described for Musca domestica, Calliphora erythrocephala, Sarcophaga bullata, Cuterebra tenebrosa, Oestrus ovis and Dermatobia hominis. Four developmental stages may be described: (1 the larva-pupa apolysis, after three hours; (2 the criptocephalic pupa, after six hours; (3 the phanerocephalic pupa, after nine hours; (4 the pharate pupa, after nine hours. The pharate adult is completely formed after 81 hours.Desenvolvimento intra-pupal de fêmeas de Chrysomya albiceps (Wiedemann (Diptera, Calliphoridae A cronologia e as mudanças morfológicas que ocorrem durante o desenvolvimento intra-pupal de Chrysomya albiceps são descritos com base em 254 espécimes criados em laboratório. As larvas foram obtidas a partir os ovos postos por uma única fêmea. As pré-pupas foram separadas de acordo com a redução do comprimento larval, o grau de pigmentação e esclerotização da cutícula, depois da formação das pupas, 10 indivíduos foram fixados em solução de Carnoy e conservados em etanol

The interface between research on individual difference variables and teaching practice: The case of cognitive factors and personality

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Adriana Biedroń

2016-09-01

Full Text Available While a substantial body of empirical evidence has been accrued about the role of individual differences in second language acquisition, relatively little is still known about how factors of this kind can mediate the effects of instructional practices as well as how empirically-derived insights can inform foreign language pedagogy, both with respect to shaping certain variables and adjusting instruction to individual learner profiles. The present paper is an attempt to shed light on the interface between research on individual difference factors and teaching practice, focusing upon variables which do not easily lend themselves to external manipulation, namely intelligence, foreign language aptitude, working memory and personality, with the role of the last of these in language learning being admittedly the least obvious. In each case, the main research findings will briefly be outlined, their potential for informing instruction will be considered, and, in the final part, the caveats concerning practical applications of research on the variables in question will be spelled out.

Students' daily emotions in the classroom : Intra-individual variability and appraisal correlates

NARCIS (Netherlands)

Ahmed, Wondimu; van der Werf, Greetje; Minnaert, Alexander; Kuyper, Hans

2010-01-01

BACKGROUND: Recent literature on emotions in education has shown that competence- and value-related beliefs are important sources of students' emotions; nevertheless, the role of these antecedents in students' daily functioning in the classroom is not yet well-known. More importantly, to date we

Strong selective sweeps associated with ampliconic regions in great ape X chromosomes

DEFF Research Database (Denmark)

Nam, Kiwoong; Munch, Kasper; Hobolth, Asger

2014-01-01

The unique inheritance pattern of X chromosomes makes them preferential targets of adaptive evolution. We here investigate natural selection on the X chromosome in all species of great apes. We find that diversity is more strongly reduced around genes on the X compared with autosomes...... with ampliconic sequences we propose that intra-genomic conflict between the X and the Y chromosomes is a major driver of X chromosome evolution....

Automated longitudinal intra-subject analysis (ALISA) for diffusion MRI tractography

DEFF Research Database (Denmark)

Aarnink, Saskia H; Vos, Sjoerd B; Leemans, Alexander

2014-01-01

the inter-subject and intra-subject automation in this situation are intended for subjects without gross pathology. In this work, we propose such an automated longitudinal intra-subject analysis (dubbed ALISA) approach, and assessed whether ALISA could preserve the same level of reliability as obtained....... The major disadvantage of manual FT segmentations, unfortunately, is that placing regions-of-interest for tract selection can be very labor-intensive and time-consuming. Although there are several methods that can identify specific WM fiber bundles in an automated way, manual FT segmentations across...... multiple subjects performed by a trained rater with neuroanatomical expertise are generally assumed to be more accurate. However, for longitudinal DTI analyses it may still be beneficial to automate the FT segmentation across multiple time points, but then for each individual subject separately. Both...

Sparse multivariate measures of similarity between intra-modal neuroimaging datasets

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Maria J. Rosa

2015-10-01

Full Text Available An increasing number of neuroimaging studies are now based on either combining more than one data modality (inter-modal or combining more than one measurement from the same modality (intra-modal. To date, most intra-modal studies using multivariate statistics have focused on differences between datasets, for instance relying on classifiers to differentiate between effects in the data. However, to fully characterize these effects, multivariate methods able to measure similarities between datasets are needed. One classical technique for estimating the relationship between two datasets is canonical correlation analysis (CCA. However, in the context of high-dimensional data the application of CCA is extremely challenging. A recent extension of CCA, sparse CCA (SCCA, overcomes this limitation, by regularizing the model parameters while yielding a sparse solution. In this work, we modify SCCA with the aim of facilitating its application to high-dimensional neuroimaging data and finding meaningful multivariate image-to-image correspondences in intra-modal studies. In particular, we show how the optimal subset of variables can be estimated independently and we look at the information encoded in more than one set of SCCA transformations. We illustrate our framework using Arterial Spin Labelling data to investigate multivariate similarities between the effects of two antipsychotic drugs on cerebral blood flow.

Intra-individual comparison of magnesium citrate and sodium phosphate for bowel preparation at CT colonography: Automated volumetric analysis of residual fluid for quality assessment

International Nuclear Information System (INIS)

Bannas, P.; Bakke, J.; Munoz del Rio, A.; Pickhardt, P.J.

2014-01-01

Aim: To perform an objective, intra-individual comparison of residual colonic fluid volume and attenuation associated with the current front-line laxative magnesium citrate (MgC) versus the former front-line laxative sodium phosphate (NaP) at CT colonography (CTC). Materials and methods: This retrospective Health Insurance and Portability and Accountability Act-compliant study had institutional review board approval; informed consent was waived. The study cohort included 250 asymptomatic adults (mean age at index 56.1 years; 124 male/126 female) who underwent CTC screening twice over a 5 year interval. Colon catharsis at initial and follow-up screening employed single-dose NaP and double-dose MgC, respectively, allowing for intra-patient comparison. Automated volumetric analysis of residual colonic fluid volume and attenuation was performed on all 500 CTC studies. Colonic fluid volume <200 ml and mean attenuation between 300–900 HU were considered optimal. Paired t-test and McNemar's test were used to compare differences. Results: Residual fluid volumes <200 ml were recorded in 192 examinations (76.8%) following MgC and in 204 examinations (81.6%) following NaP (p = 0.23). The mean total residual fluid volume was 155 ± 114 ml for MgC and 143 ± 100 ml for NaP (p = 0.01). The attenuation range of 300–900 HU was significantly more frequent for MgC (n = 220, 88%) than for NaP (n = 127, 50.8%; p < 0.001). Mean fluid attenuation was significantly lower for MgC (700 ± 165 HU) than for NaP (878 ± 155 HU; p < 0.001). Concomitant presence of both optimal fluid volume and attenuation was significantly more frequent for MgC 65.2% than for NaP (38%; p < 0.001). Conclusions: Objective intra-individual comparison using automated volumetric analysis suggests that the replacement of NaP by MgC as the front-line laxative for CTC has not compromised overall examination quality. - Highlights: • Automated volumetric analysis provides

Enamel biorhythms of humans and great apes: the Havers-Halberg Oscillation hypothesis reconsidered.

Science.gov (United States)

Mahoney, Patrick; Miszkiewicz, Justyna J; Pitfield, Rosie; Deter, Chris; Guatelli-Steinberg, Debbie

2017-02-01

The Havers-Halberg Oscillation (HHO) hypothesis links evidence for the timing of a biorhythm retained in permanent tooth enamel (Retzius periodicity) to adult body mass and life history traits across mammals. Potentially, these links provide a way to access life history of fossil species from teeth. Recently we assessed intra-specific predictions of the HHO on human children. We reported Retzius periodicity (RP) corresponded with enamel thickness, and cusp formation time, when calculated from isolated deciduous teeth. We proposed the biorhythm might not remain constant within an individual. Here, we test our findings. RP is compared between deciduous second and permanent first molars within the maxillae of four human children. Following this, we report the first RPs for deciduous teeth from modern great apes (n = 4), and compare these with new data for permanent teeth (n = 18) from these species, as well as with previously published values. We also explore RP in teeth that retain hypoplastic defects. Results show RP changed within the maxilla of each child, from thinner to thicker enameled molars, and from one side of a hypoplastic defect to the other. When considered alongside correlations between RP and cusp formation time, these observations provide further evidence that RP is associated with enamel growth processes and does not always remain constant within an individual. RP of 5 days for great ape deciduous teeth lay below the lowermost range of those from permanent teeth of modern orangutan and gorilla, and within the lowermost range of RPs from chimpanzee permanent teeth. Our data suggest associations between RP and enamel growth processes of humans might extend to great apes. These findings provide a new framework from which to develop the HHO hypothesis, which can incorporate enamel growth along with other physiological systems. Applications of the HHO to fossil teeth should avoid transferring RP between deciduous and permanent enamel, or including

Designing low-carbon power systems for Great Britain in 2050 that are robust to the spatiotemporal and inter-annual variability of weather

Science.gov (United States)

Zeyringer, Marianne; Price, James; Fais, Birgit; Li, Pei-Hao; Sharp, Ed

2018-05-01

The design of cost-effective power systems with high shares of variable renewable energy (VRE) technologies requires a modelling approach that simultaneously represents the whole energy system combined with the spatiotemporal and inter-annual variability of VRE. Here, we soft-link a long-term energy system model, which explores new energy system configurations from years to decades, with a high spatial and temporal resolution power system model that captures VRE variability from hours to years. Applying this methodology to Great Britain for 2050, we find that VRE-focused power system design is highly sensitive to the inter-annual variability of weather and that planning based on a single year can lead to operational inadequacy and failure to meet long-term decarbonization objectives. However, some insights do emerge that are relatively stable to weather-year. Reinforcement of the transmission system consistently leads to a decrease in system costs while electricity storage and flexible generation, needed to integrate VRE into the system, are generally deployed close to demand centres.

GREAT: a web portal for Genome Regulatory Architecture Tools.

Science.gov (United States)

Bouyioukos, Costas; Bucchini, François; Elati, Mohamed; Képès, François

2016-07-08

GREAT (Genome REgulatory Architecture Tools) is a novel web portal for tools designed to generate user-friendly and biologically useful analysis of genome architecture and regulation. The online tools of GREAT are freely accessible and compatible with essentially any operating system which runs a modern browser. GREAT is based on the analysis of genome layout -defined as the respective positioning of co-functional genes- and its relation with chromosome architecture and gene expression. GREAT tools allow users to systematically detect regular patterns along co-functional genomic features in an automatic way consisting of three individual steps and respective interactive visualizations. In addition to the complete analysis of regularities, GREAT tools enable the use of periodicity and position information for improving the prediction of transcription factor binding sites using a multi-view machine learning approach. The outcome of this integrative approach features a multivariate analysis of the interplay between the location of a gene and its regulatory sequence. GREAT results are plotted in web interactive graphs and are available for download either as individual plots, self-contained interactive pages or as machine readable tables for downstream analysis. The GREAT portal can be reached at the following URL https://absynth.issb.genopole.fr/GREAT and each individual GREAT tool is available for downloading. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Intra-fractional uncertainties in image-guided intensity-modulated radiotherapy (IMRT) of prostate cancer

International Nuclear Information System (INIS)

Polat, Buelent; Guenther, Iris; Wilbert, Juergen; Goebel, Joachim; Sweeney, Reinhart A.; Flentje, Michael; Guckenberger, Matthias

2008-01-01

To evaluate intra-fractional uncertainties during intensity-modulated radiotherapy (IMRT) of prostate cancer. During IMRT of 21 consecutive patients, kilovolt (kV) cone-beam computed tomography (CBCT) images were acquired prior to and immediately after treatment: a total of 252 treatment fractions with 504 CBCT studies were basis of this analysis. The prostate position in anterior-posterior (AP) direction was determined using contour matching; patient set-up based on the pelvic bony anatomy was evaluated using automatic image registration. Internal variability of the prostate position was the difference between absolute prostate and patient position errors. Intra-fractional changes of prostate position, patient position, rectal distension in AP direction and bladder volume were analyzed. With a median treatment time of 16 min, intra-fractional drifts of the prostate were > 5 mm in 12% of all fractions and a margin of 6 mm was calculated for compensation of this uncertainty. Mobility of the prostate was independent from the bony anatomy with poor correlation between absolute prostate motion and motion of the bony anatomy (R 2 = 0.24). A systematic increase of bladder filling by 41 ccm on average was observed; however, these changes did not influence the prostate position. Small variations of the prostate position occurred independently from intra-fractional changes of the rectal distension; a weak correlation between large internal prostate motion and changes of the rectal volume was observed (R 2 = 0.55). Clinically significant intra-fractional changes of the prostate position were observed and margins of 6 mm were calculated for this intra-fractional uncertainty. Repeated or continuous verification of the prostate position may allow further margin reduction. (orig.)

Intra-fractional uncertainties in image-guided intensity-modulated radiotherapy (IMRT) of prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Polat, Buelent; Guenther, Iris; Wilbert, Juergen; Goebel, Joachim; Sweeney, Reinhart A.; Flentje, Michael; Guckenberger, Matthias [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology

2008-12-15

To evaluate intra-fractional uncertainties during intensity-modulated radiotherapy (IMRT) of prostate cancer. During IMRT of 21 consecutive patients, kilovolt (kV) cone-beam computed tomography (CBCT) images were acquired prior to and immediately after treatment: a total of 252 treatment fractions with 504 CBCT studies were basis of this analysis. The prostate position in anterior-posterior (AP) direction was determined using contour matching; patient set-up based on the pelvic bony anatomy was evaluated using automatic image registration. Internal variability of the prostate position was the difference between absolute prostate and patient position errors. Intra-fractional changes of prostate position, patient position, rectal distension in AP direction and bladder volume were analyzed. With a median treatment time of 16 min, intra-fractional drifts of the prostate were > 5 mm in 12% of all fractions and a margin of 6 mm was calculated for compensation of this uncertainty. Mobility of the prostate was independent from the bony anatomy with poor correlation between absolute prostate motion and motion of the bony anatomy (R{sup 2} = 0.24). A systematic increase of bladder filling by 41 ccm on average was observed; however, these changes did not influence the prostate position. Small variations of the prostate position occurred independently from intra-fractional changes of the rectal distension; a weak correlation between large internal prostate motion and changes of the rectal volume was observed (R{sup 2} = 0.55). Clinically significant intra-fractional changes of the prostate position were observed and margins of 6 mm were calculated for this intra-fractional uncertainty. Repeated or continuous verification of the prostate position may allow further margin reduction. (orig.)

THE INTRA- AND INTER-RATER RELIABILITY OF THE SOCCER INJURY MOVEMENT SCREEN (SIMS).

Science.gov (United States)

McCunn, Robert; Aus der Fünten, Karen; Govus, Andrew; Julian, Ross; Schimpchen, Jan; Meyer, Tim

2017-02-01

The growing volume of movement screening research reveals a belief among practitioners and researchers alike that movement quality may have an association with injury risk. However, existing movement screening tools have not considered the sport-specific movement and injury patterns relevant to soccer. The present study introduces the Soccer Injury Movement Screen (SIMS), which has been designed specifically for use within soccer. Furthermore, the purpose of the present study was to assess the intra- and inter-rater reliability of the SIMS and determine its suitability for use in further research. The study utilized a test-retest design to discern reliablility. Twenty-five (11 males, 14 females) healthy, recreationally active university students (age 25.5 ± 4.0 years, height 171 ± 9 cm, weight 64.7 ± 12.6 kg) agreed to participate. The SIMS contains five sub-tests: the anterior reach, single-leg deadlift, in-line lunge, single-leg hop for distance and tuck jump. Each movement was scored out of 10 points and summed to produce a composite score out of 50. The anterior reach and single-leg hop for distance were scored in real-time while the remaining tests were filmed and scored retrospectively. Three raters conducted the SIMS with each participant on three occasions separated by an average of three and a half days (minimum one day, maximum seven days). Rater 1 re-scored the filmed movements for all participants on all occasions six months later to establish the 'pure' intra-rater (intra-occasion) reliability for those movements. Intraclass correlation coefficient (ICC) values for intra- and inter-rater composite score reliability ranged from 0.66-0.72 and 0.79-0.86 respectively. Weighted kappa values representing the intra- and inter-rater reliability of the individual sub-tests ranged from 0.35-0.91 indicating fair to almost perfect agreement. Establishing the reliability of the SIMS is a prerequisite for further research seeking to investigate

Inter- and intra-specimen variability masks reliable temperature control on shell Mg/Ca ratios in laboratory- and field-cultured Mytilus edulis and Pecten maximus (bivalvia

Directory of Open Access Journals (Sweden)

H. A. Kennedy

2008-09-01

Full Text Available The Mg/Ca ratios of biogenic calcite is commonly seen as a valuable palaeo-proxy for reconstructing past ocean temperatures. The temperature dependence of Mg/Ca ratios in bivalve calcite has been the subject of contradictory observations. The palaeoceanographic use of a geochemical proxy is dependent on initial, rigorous calibration and validation of relationships between the proxy and the ambient environmental variable to be reconstructed. Shell Mg/Ca ratio data are reported for the calcite of two bivalve species, Mytilus edulis (common mussel and Pecten maximus (king scallop, which were grown in laboratory culturing experiments at controlled and constant aquarium seawater temperatures over a range from ~10 to ~20°C. Furthermore, Mg/Ca ratio data of laboratory- and field-grown M. edulis specimens were compared. Only a weak, albeit significant, shell Mg/Ca ratio–temperature relationship was observed in the two bivalve species: M. edulis (r2=0.37, p0.001 for laboratory-cultured specimens and r2=0.50, p0.001 for field-cultured specimens and P. maximus (r2=0.21, p0.001 for laboratory-cultured specimens only. In the two species, shell Mg/Ca ratios were not found to be controlled by shell growth rate or salinity. The Mg/Ca ratios in the shells exhibited a large degree of variability among and within species and individuals. The results suggest that the use of bivalve calcite Mg/Ca ratios as a temperature proxy is limited, at least in the species studied to date. Such limitations are most likely due to the presence of physiological effects on Mg incorporation in bivalve calcite. The utilization is further limited by the great variability both within and among shells of the same species that were precipitated under the same ambient conditions.

Differences in work values : understanding the role of intra- versus inter-country variation

NARCIS (Netherlands)

van Hoorn, A.A.J.

2015-01-01

A growing literature emphasizes the need for studies taking a contingency perspective to international HRM to move beyond mean country differences in work values and begin considering intra-country variation (ICV). We use individual-level data on Hofstedeian values—not hitherto available—to infuse

INDIVIDUAL AND ORGANIZATIONAL VARIABLES AFFECTING THE USE OF PERSONAL PROTECTIVE EQUIPMENT

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TUNÇ DEMİRBİLEK

2013-06-01

Full Text Available Management’s safety approach and commitment are related to occupational health and safety applications in workplaces. However, personal characteristics and attitudes on their health of employees are very influential factors on occupational health and safety applications. For examine of interaction between behaviors and the health and safety applications it is required that determine of employee’s perceptions. For this reason this paper’s purpose is to establish of safety needs, attitudes and behaviors of employees and their perceptions regarding management’s safety approach and applications. The study’s focal point is use of personal protective equipment as an indicator “safety behavior”. In empirical study, assumption variables regarding the use of personal protective equipment are safety effectively, safety need, management attitudes and protective equipment conditions. The fundamental hypothesis of this paper is use of personal protective equipment is related to individual and organizational variables. Implications of research findings are to indicate impelling the workers to safety behaviour or using the personal protective equipment by their feeling of the safety behaviour and availability of personal protective equipment.

HORIZONTAL AND VERTICAL INTRA-INDUSTRY TRADE OF TURKEY

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NEVZAT ŞİMŞEK

2013-06-01

Full Text Available Crucial improvement have taken place in intra-industry trade literature since intra-industry trade phenomenon was empirically determined. Nowadays economists discuss on the necessity of distinguishing between horizontal and vertical intra-industry trade especially relating to product differentiation in each industry. As standard Grubel-Lloyd index does not determine the time when two way trade is taken into consideration, in this paper first of all Two-Way Trade index is used and then horizontal intra-industry trade and low-high quality vertical intra-industry trade are distinguished from each other regarding unit value differential. As a result of the analysis the findings show that low quality vertical intra-industry trade dominate in Turkey's intra-industry trade.

Intra-lesional spatial correlation of static and dynamic FET-PET parameters with MRI-based cerebral blood volume in patients with untreated glioma

Energy Technology Data Exchange (ETDEWEB)

Goettler, Jens; Preibisch, Christine [TU Muenchen, Department of Neuroradiology, Klinikum rechts der Isar, Munich (Germany); TU Muenchen, TUM Neuroimaging Center (TUM-NIC), Klinikum rechts der Isar, Munich (Germany); Lukas, Mathias; Mustafa, Mona; Schwaiger, Markus; Pyka, Thomas [TU Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Kluge, Anne; Kaczmarz, Stephan; Zimmer, Claus [TU Muenchen, Department of Neuroradiology, Klinikum rechts der Isar, Munich (Germany); Gempt, Jens; Ringel, Florian; Meyer, Bernhard [TU Muenchen, Department of Neurosurgery, Klinikum rechts der Isar, Munich (Germany); Foerster, Stefan [TU Muenchen, TUM Neuroimaging Center (TUM-NIC), Klinikum rechts der Isar, Munich (Germany); TU Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Klinikum Bayreuth, Department of Nuclear Medicine, Bayreuth (Germany)

2017-03-15

{sup 18}F-fluorethyltyrosine-(FET)-PET and MRI-based relative cerebral blood volume (rCBV) have both been used to characterize gliomas. Recently, inter-individual correlations between peak static FET-uptake and rCBV have been reported. Herein, we assess the local intra-lesional relation between FET-PET parameters and rCBV. Thirty untreated glioma patients (27 high-grade) underwent simultaneous PET/MRI on a 3 T hybrid scanner obtaining structural and dynamic susceptibility contrast sequences. Static FET-uptake and dynamic FET-slope were correlated with rCBV within tumour hotspots across patients and intra-lesionally using a mixed-effects model to account for inter-individual variation. Furthermore, maximal congruency of tumour volumes defined by FET-uptake and rCBV was determined. While the inter-individual relationship between peak static FET-uptake and rCBV could be confirmed, our intra-lesional, voxel-wise analysis revealed significant positive correlations (median r = 0.374, p < 0.0001). Similarly, significant inter- and intra-individual correlations were observed between FET-slope and rCBV. However, rCBV explained only 12% of the static and 5% of the dynamic FET-PET variance and maximal overlap of respective tumour volumes was 37% on average. Our results show that the relation between peak values of MR-based rCBV and static FET-uptake can also be observed intra-individually on a voxel basis and also applies to a dynamic FET parameter, possibly determining hotspots of higher biological malignancy. However, just a small part of the FET-PET signal variance is explained by rCBV and tumour volumes determined by the two modalities showed only moderate overlap. These findings indicate that FET-PET and MR-based rCBV provide both congruent and complimentary information on glioma biology. (orig.)

Intra-annual variability of carbon and nitrogen stable isotopes in suspended organic matter in waters of the western continental shelf of India

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M. V. Maya

2011-11-01

Full Text Available Intra-annual variations of δ¹³C and δ¹⁵N of water-column suspended particulate organic matter (SPOM have been investigated to understand the biogeochemical cycling of C and N in the Western Continental Shelf of India (WCSI. The key issues being addressed are: how the δ¹⁵N of SPOM is affected by seasonally varying processes of organic matter production and respiration and how it relates to the δ¹⁵N of sedimentary organic matter that appears to show a decreasing trend despite an apparent intensification of seasonal oxygen deficiency over the past few decades? A secondary objective was to evaluate the sources of organic carbon. Elemental carbon and nitrogen concentrations, C/N ratios in SPOM, along with ancillary chemical and biological variables including phytoplankton pigment abundance were also determined on a seasonal basis (from March 2007 to September 2008, with the partial exception of the southwest (SW monsoon period. The results reveal significant shifts in isotopic signatures, especially δ¹⁵N, of SPOM before and after the onset of SW monsoon. Very low δ¹⁵N values, reaching a minimum of −4.17 ‰, are found during the pre-monsoon period. Our results provide the first direct evidence for the addition of substantial amounts of isotopically light nitrogen by the diazotrophs, especially Trichodesmium, in the region. The δ¹⁵N of SPOM is generally lower than the mean value (7.38 ‰ for surficial sediments, presumably because of diagenetic enrichment. The results support the view that sedimentary δ¹⁵N may not necessarily reflect denitrification intensity in the overlying waters due to diverse sources of nitrogen and variability of its isotopic composition. The observed intra-annual variability of δ¹³C of SPOM during the pre-monsoon and post-monsoon periods is generally small. Phytoplankton production and probably species

Great ape genetic diversity and population history

DEFF Research Database (Denmark)

Prado-Martinez, Javier; Sudmant, Peter H; Kidd, Jeffrey M

2013-01-01

Most great ape genetic variation remains uncharacterized; however, its study is critical for understanding population history, recombination, selection and susceptibility to disease. Here we sequence to high coverage a total of 79 wild- and captive-born individuals representing all six great ape...

Effects of hip joint position and intra-capsular volume on hip joint intra-capsular pressure: a human cadaveric model

Directory of Open Access Journals (Sweden)

Tse Paul

2009-04-01

Full Text Available Abstract Background Increase in hip intra-capsular pressure has been implicated in various hip pathologies, such as avascular necrosis complicating undisplaced femoral neck fracture. Our study aimed at documenting the relationship between intra-capsular volume and pressure in various hip positions. Methods Fifty-two cadaveric hips were studied. An electronic pressure-monitoring catheter recorded the intra-capsular hip pressure after each instillation of 2 ml of normal saline and in six hip positions. Results In neutral hip position, the control position for investigation, intra-capsular pressure remained unchanged when its content was below 10 ml. Thereafter, it increased exponentially. When the intra-capsular volume was 12 ml, full abduction produced a 2.1-fold increase (p = 0.028 of the intra-capsular hip joint pressure; full external rotation and full internal rotation increased the pressure by at least 4-fold (p Conclusion Intra-capsular pressure increases with its volume, but with a wide variation with different positions. It would be appropriate to recommend that hips with haemarthrosis or effusion should be positioned in 45-degree flexion.

Predicting Change in Postpartum Depression: An Individual Growth Curve Approach.

Science.gov (United States)

Buchanan, Trey

Recently, methodologists interested in examining problems associated with measuring change have suggested that developmental researchers should focus upon assessing change at both intra-individual and inter-individual levels. This study used an application of individual growth curve analysis to the problem of maternal postpartum depression.…

Individual Endurance Training Prescription with Heart Rate Variability.

Science.gov (United States)

Vesterinen, Ville; Nummela, Ari; Heikura, Ida; Laine, Tanja; Hynynen, Esa; Botella, Javier; Häkkinen, Keijo

2016-07-01

Measures of HR variability (HRV) have shown potential to be of use in training prescription. The aim of this study was to investigate the effectiveness of using HRV in endurance training prescription. Forty recreational endurance runners were divided into the HRV-guided experimental training group (EXP) and traditional predefined training group (TRAD). After a 4-wk preparation training period, TRAD trained according to a predefined training program including two to three moderate- (MOD) and high-intensity training (HIT) sessions per week during an 8-wk intensive training period. The timing of MOD and HIT sessions in EXP was based on HRV, measured every morning. The MOD/HIT session was programmed if HRV was within an individually determined smallest worthwhile change. Otherwise, low-intensity training was performed. Maximal oxygen consumption (V˙O2max) and 3000-m running performance (RS3000m) were measured before and after both training periods. The number of MOD and HIT sessions was significantly lower (P = 0.021, effect size = 0.98) in EXP (13.2 ± 6.0 sessions) compared with TRAD (17.7 ± 2.5 sessions). No other differences in training were found between the groups. RS3000m improved in EXP (2.1% ± 2.0%, P = 0.004) but not in TRAD (1.1% ± 2.7%, P = 0.118) during the intensive training period. A small between-group difference (effect size = 0.42) was found in the change in RS3000m. V˙O2max improved in both groups (EXP: 3.7% ± 4.6%, P = 0.027; TRAD: 5.0% ± 5.2%, P = 0.002). The results of the present study suggest the potential of resting HRV to prescribe endurance training by individualizing the timing of vigorous training sessions.

Individual variability of Scots pine Pinus sylvestris L. by the drought resistance features in forest-steppe pine forests of south Siberia

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N. A. Tikhonova

2016-10-01

Full Text Available The drought resistance of trees in the Scots pine Pinus sylvestris L. populations was studied under forest steppe conditions of southern Siberia. We found large differences amongthe treesin the time and rate of needles dehydration. In the populations of the more arid growing conditions (Shira, Balgazyn the rate of loss 50 % of the water was three to four times lower than in the population of the more favorable conditions for growth (Minusinsk. It has been established that the variability of water-holding capacity of needles from individual trees in populations varies from high to very high levels. On the contrary, for the water absorption capacity of needles characteristically has variability, as within population and between them. Is marked a great assessment reliability of water holding capacity of the needles under the pooled analysis of absolute and relative indicators of dynamics of the needles degradration. We investigated the correlation of needles’ water retention signs with a height and heterozygosity of trees. It was found that under more favorable conditions of the growth the large part of sample are the trees with a direct connection between heterozygosity and drought resistance of tree and in the worst conditions – with a reverse. The correlations of water-holding capacity of needles with the height of the tree are ambiguous: in the Minusinsk sample, the most of drought-resistant trees are characterized by better growth, in Balgazyn population – conversely. Some dwarf individuals from the Balgazyn and Shira populations in terms of drought tolerance are at same level as the typical trees, among the less drought-resistant trees found as dwarfs, and typical trees. It was concluded that there are trees in populations with different strategies to adaptation to the moisture deficit.

Reproducibility, stability, and biological variability of thrombin generation using calibrated automated thrombography in healthy dogs.

Science.gov (United States)

Cuq, Benoît; Blois, Shauna L; Wood, R Darren; Monteith, Gabrielle; Abrams-Ogg, Anthony C; Bédard, Christian; Wood, Geoffrey A

2018-06-01

Thrombin plays a central role in hemostasis and thrombosis. Calibrated automated thrombography (CAT), a thrombin generation assay, may be a useful test for hemostatic disorders in dogs. To describe CAT results in a group of healthy dogs, and assess preanalytical variables and biological variability. Forty healthy dogs were enrolled. Lag time (Lag), time to peak (ttpeak), peak thrombin generation (peak), and endogenous thrombin potential (ETP) were measured. Direct jugular venipuncture and winged-needle catheter-assisted saphenous venipuncture were used to collect samples from each dog, and results were compared between methods. Sample stability at -80°C was assessed over 12 months in a subset of samples. Biological variability of CAT was assessed via nested ANOVA using samples obtained weekly from a subset of 9 dogs for 4 consecutive weeks. Samples for CAT were stable at -80°C over 12 months of storage. Samples collected via winged-needle catheter venipuncture showed poor repeatability compared to direct venipuncture samples; there was also poor agreement between the 2 sampling methods. Intra-individual variability of CAT parameters was below 25%; inter-individual variability ranged from 36.9% to 78.5%. Measurement of thrombin generation using CAT appears to be repeatable in healthy dogs, and samples are stable for at least 12 months when stored at -80°C. Direct venipuncture sampling is recommended for CAT. Low indices of individuality suggest that subject-based reference intervals are more suitable when interpreting CAT results. © 2018 American Society for Veterinary Clinical Pathology.

Spatial and temporal variability of winds in the Northern European Seas

DEFF Research Database (Denmark)

Karagali, Ioanna; Badger, Merete; Hahmann, Andrea N.

2013-01-01

the spatial and temporal variability of the near-surface wind field, including the inter- and intra-annual variability for resource assessment purposes. This study demonstrates the applicability of satellite observations as the means to provide information useful for selecting areas to perform higher...

French Nursery Schools and German Kindergartens: Effects of Individual and Contextual Variables on Early Learning

Science.gov (United States)

Tazouti, Youssef; Viriot-Goeldel, Caroline; Matter, Cornelie; Geiger-Jaillet, Anemone; Carol, Rita; Deviterne, Dominique

2011-01-01

The present article investigates the effects of individual and contextual variables on children's early learning in French nursery schools and German kindergartens. Our study of 552 children at preschools in France (299 children from French nursery schools) and Germany (253 children from German kindergartens) measured skills that facilitate the…

TAX TREATMENT SPECIFIC TO INTRA COMMUNITY COMMERCIAL BUSINESS TRANSACTIONS - ACQUISITION AND INTRA-COMMUNITY SUPPLY OF GOODS

Directory of Open Access Journals (Sweden)

Paliu -Popa Lucia

2009-11-01

Full Text Available Romania's accession to the European Union has imposed harmonize national legislation with Community law, registering significant changes in the tax area, particularly on value added tax. In order to determine the person liable to pay value added tax, related to intra-community commercial transactions, must to clarify tax matters for those operations. Given the complexity of intra-community commercial transactions and their taxation, in the following issues we will address the intra-community trade in goods, with reference to specific tax treatment of supplies and intra-community acquisitions of goods. To do this we will consider more specific situations that arise in trade relationship between EU Member States, examples that will allow us to draw some conclusions on tax matters arising in intracommunity commercial relationship

Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

Science.gov (United States)

Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael; Jeffery, Brian M.

2013-12-01

Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intra-population variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

Individual differences in heart rate variability are associated with the avoidance of negative emotional events.

Science.gov (United States)

Katahira, Kentaro; Fujimura, Tomomi; Matsuda, Yoshi-Taka; Okanoya, Kazuo; Okada, Masato

2014-12-01

Although the emotional outcome of a choice generally affects subsequent decisions, humans can inhibit the influence of emotion. Heart rate variability (HRV) has emerged as an objective measure of individual differences in the capacity for inhibitory control. In the present study, we investigated how individual differences in HRV at rest are associated with the emotional effects of the outcome of a choice on subsequent decision making using a decision-making task in which emotional pictures appeared as decision outcomes. We used a reinforcement learning model to characterize the observed behaviors according to several parameters, namely, the learning rate and the motivational value of positive and negative pictures. Consequently, we found that individuals with a lower resting HRV exhibited a greater negative motivational value in response to negative pictures, suggesting that these individuals tend to avoid negative pictures compared with individuals with a higher resting HRV. Copyright © 2014 Elsevier B.V. All rights reserved.

Analysis of individual cells identifies cell-to-cell variability following induction of cellular senescence.

Science.gov (United States)

Wiley, Christopher D; Flynn, James M; Morrissey, Christapher; Lebofsky, Ronald; Shuga, Joe; Dong, Xiao; Unger, Marc A; Vijg, Jan; Melov, Simon; Campisi, Judith

2017-10-01

Senescent cells play important roles in both physiological and pathological processes, including cancer and aging. In all cases, however, senescent cells comprise only a small fraction of tissues. Senescent phenotypes have been studied largely in relatively homogeneous populations of cultured cells. In vivo, senescent cells are generally identified by a small number of markers, but whether and how these markers vary among individual cells is unknown. We therefore utilized a combination of single-cell isolation and a nanofluidic PCR platform to determine the contributions of individual cells to the overall gene expression profile of senescent human fibroblast populations. Individual senescent cells were surprisingly heterogeneous in their gene expression signatures. This cell-to-cell variability resulted in a loss of correlation among the expression of several senescence-associated genes. Many genes encoding senescence-associated secretory phenotype (SASP) factors, a major contributor to the effects of senescent cells in vivo, showed marked variability with a subset of highly induced genes accounting for the increases observed at the population level. Inflammatory genes in clustered genomic loci showed a greater correlation with senescence compared to nonclustered loci, suggesting that these genes are coregulated by genomic location. Together, these data offer new insights into how genes are regulated in senescent cells and suggest that single markers are inadequate to identify senescent cells in vivo. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

What great managers do.

Science.gov (United States)

Buckingham, Marcus

2005-03-01

Much has been written about the qualities that make a great manager, but most of the literature overlooks a fundamental question: What does a great manager actually do? While there are countless management styles, one thing underpins the behavior of all great managers. Above all, an exceptional manager comes to know and value the particular quirks and abilities of her employees. She figures out how to capitalize on her staffers' strengths and tweaks her environment to meet her larger goals. Such a specialized approach may seem like a lot of work. But in fact, capitalizing on each person's uniqueness can save time. Rather than encourage employees to conform to strict job descriptions that may include tasks they don't enjoy and aren't good at, a manager who develops positions for his staff members based on their unique abilities will be rewarded with behaviors that are far more efficient and effective than they would be otherwise. This focus on individuals also makes employees more accountable. Because staffers are evaluated on their particular strengths and weaknesses, they are challenged to take responsibility for their abilities and to hone them. Capitalizing on a person's uniqueness also builds a stronger sense of team. By taking the time to understand what makes each employee tick, a great manager shows that he sees his people for who they are. This personal investment not only motivates individuals but also galvanizes the entire team. Finally, this approach shakes up existing hierarchies, which leads to more creative thinking. To take great managing from theory to practice, the author says, you must know three things about a person: her strengths, the triggers that activate those strengths, and how she learns. By asking the right questions, squeezing the right triggers, and becoming aware of your employees' learning styles, you will discover what motivates each person to excel.

Feeling old today? Daily health, stressors, and affect explain day-to-day variability in subjective age.

Science.gov (United States)

Kotter-Grühn, Dana; Neupert, Shevaun D; Stephan, Yannick

2015-01-01

Subjective age is an important correlate of health, well-being, and longevity. So far, little is known about short-term variability in subjective age and the circumstances under which individuals feel younger/older in daily life. This study examined whether (a) older adults' felt age fluctuates on a day-to-day basis, (b) daily changes in health, stressors, and affect explain fluctuations in felt age, and (c) the daily associations between felt age and health, stressors, or affect are time-ordered. Using an eight-day daily diary approach, N = 43 adults (60-96 years, M = 74.65, SD = 8.19) filled out daily questionnaires assessing subjective age, health, daily stressors, and affect. Data were analysed using multilevel modelling. Subjective age, health, daily stressors, affect. Intra-individual variability in felt age was not explained by time but by short-term variability in other variables. Specifically, on days when participants experienced more than average health problems, stress, or negative affect they felt older than on days with average health, stress, or negative affect. No time-ordered effects were found. Bad health, many stressors, and negative affective experiences constitute circumstances under which older adults feel older than they typically do. Thus, daily measures of subjective age could be markers of health and well-being.

Intra-urban and street scale variability of BTEX, NO 2 and O 3 in Birmingham, UK: Implications for exposure assessment

Science.gov (United States)

Vardoulakis, Sotiris; Solazzo, Efisio; Lumbreras, Julio

2011-09-01

Automatic monitoring networks have the ability of capturing air pollution episodes, as well as short- and long-term air quality trends in urban areas that can be used in epidemiological studies. However, due to practical constraints (e.g. cost and bulk of equipment), the use of automatic analysers is restricted to a limited number of roadside and background locations within a city. As a result, certain localised air pollution hotspots may be overlooked or overemphasised, especially near heavily trafficked street canyons and intersections. This has implications for compliance with regulatory standards and may cause exposure misclassification in epidemiological studies. Apart from automatic analysers, low cost passive diffusion tubes can be used to characterise the spatial variability of air pollution in urban areas. In this study, BTEX, NO 2 and O 3 data from a one-year passive sampling survey were used to characterise the intra-urban and street scale spatial variability of traffic-related pollutants in Birmingham (UK). In addition, continuous monitoring of NO 2, NO x, O 3, CO, SO 2, PM 10 and PM 2.5 from three permanent monitoring sites was used to identify seasonal and annual pollution patterns. The passive sampling measurements allowed us to evaluate the representativeness of a permanent roadside monitoring site that has recorded some of the highest NO 2 and PM 10 concentrations in Birmingham in recent years. Dispersion modelling was also used to gain further insight into pollutant sources and dispersion characteristics at this location. The strong spatial concentration gradients observed in busy streets, as well as the differences between roadside and urban background levels highlight the importance of appropriate positioning of air quality monitoring equipment in cities.

TU-A-12A-06: Intra-Observer Variability in Delineation of Target Volumes in Breast Radiotherapy and Its Effect On Accuracy of Deformation Measurements

Energy Technology Data Exchange (ETDEWEB)

Juneja, P; Harris, E [The Institute of Cancer Research, London (United Kingdom); Royal Marsden NHS Foundation Trust, Sutton (United Kingdom); Bonora, M [University of Milan, Milan (Italy); Evans, P [University of Surrey, Guildford (United Kingdom)

2014-06-15

Purpose: In breast radiotherapy, the target volume may change during treatment and need adaptation of the treatment plan. This is possible for both tumour bed (TB) and whole breast (WB) target volumes. Delineation of the target (to detect changes) is also subject to uncertainty due to intra- and inter-observer variability. This work measured the uncertainty, due to intraobserver variability, in the quantification of tissue deformation. Methods: Datasets consisting of paired prone and supine CT scans of three patients were used. Significant deformation in target volumes is expected between prone and supine patient positions. The selected cases had 1) no seroma, 2) some seroma, and 3) large seroma. The TB and WB were outlined on each dataset three times by one clinician. Delineation variability was defined as the standard deviations of the distances between observer outlines. For each target volume and each case, tissue deformation between prone and supine delineations was quantified using the Dice similarity coefficient (DSC) and the average surface distance (ASD). The uncertainty in the tissue deformation (due to delineation variability) was quantified by measuring the ranges of DSC and ASD using all combinations of pairs of outlines (9 pairs). Results: For the TB, the range of delineation variability was 0.44-1.16 mm. The deformation, DSC and ASD, (and uncertainty in measurement) of the TB between prone and supine position of the cases were: 1) 0.21 (0.17-0.28) and 12.4 mm (11.8-13 mm); 2) 0.54 (0.51-0.57) and 3.3 mm (3.1-3.5 mm); 3) 0.62 (0.61-0.64) and 4.9 mm (4.6-5.2 mm). WB deformation measurements were subject to less uncertainty due to delineation variability than TB deformation measurements. Conclusion: For the first time, the uncertainty, due to observer variability, in the measurement of the deformation of breast target volumes was investigated. Deformations in these ranges would be difficult to detect. This work was supported in part by Cancer Research

Sources of variation in innate immunity in great tit nestlings living along a metal pollution gradient: An individual-based approach

International Nuclear Information System (INIS)

Vermeulen, Anke; Müller, Wendt; Matson, Kevin D.; Irene Tieleman, B.; Bervoets, Lieven; Eens, Marcel

2015-01-01

Excessive deposition of metals in the environment is a well-known example of pollution worldwide. Chronic exposure of organisms to metals can have a detrimental effect on reproduction, behavior, health and survival, due to the negative effects on components of the immune system. However, little is known about the effects of chronic sublethal metal exposure on immunity, especially for wildlife. In our study, we examined the constitutive innate immunity of great tit (Parus major) nestlings (N = 234) living in four populations along a metal pollution gradient. For each nestling, we determined the individual metal concentrations (lead, cadmium, arsenic) present in the red blood cells and measured four different innate immune parameters (agglutination, lysis, haptoglobin concentrations and nitric oxide concentrations) to investigate the relationship between metal exposure and immunological condition. While we found significant differences in endogenous metal concentrations among populations with the highest concentrations closest to the pollution source, we did not observe corresponding patterns in our immune measures. However, when evaluating relationships between metal concentrations and immune parameters at the individual level, we found negative effects of lead and, to a lesser extent, arsenic and cadmium on lysis. In addition, high arsenic concentrations appear to elicit inflammation, as reflected by elevated haptoglobin concentrations. Thus despite the lack of a geographic association between pollution and immunity, this type of association was present at the individual level at a very early life stage. The high variation in metal concentrations and immune measures observed within populations indicates a high level of heterogeneity along an existing pollution gradient. Interestingly, we also found substantial within nest variation, for which the sources remain unclear, and which highlights the need of an individual-based approach. - Highlights: • Innate immunity

Sources of variation in innate immunity in great tit nestlings living along a metal pollution gradient: An individual-based approach

Energy Technology Data Exchange (ETDEWEB)

Vermeulen, Anke, E-mail: anke.vermeulen@uantwerpen.be [Department of Biology — Ethology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Müller, Wendt, E-mail: wendt.mueller@uantwerpen.be [Department of Biology — Ethology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium); Matson, Kevin D., E-mail: k.d.matson@rug.nl [Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen, P.O. Box 11103, 9700 CC Groningen (Netherlands); The Resource Ecology Group, Department of Environmental Sciences, Wageningen University, Droevendaalsesteeg 3a, 6708PB Wageningen (Netherlands); Irene Tieleman, B., E-mail: b.i.tieleman@rug.nl [Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen, P.O. Box 11103, 9700 CC Groningen (Netherlands); Bervoets, Lieven, E-mail: lieven.bervoets@uantwerpen.be [Department of Biology — SPHERE, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen (Belgium); Eens, Marcel, E-mail: marcel.eens@uantwerpen.be [Department of Biology — Ethology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk (Belgium)

2015-03-01

Excessive deposition of metals in the environment is a well-known example of pollution worldwide. Chronic exposure of organisms to metals can have a detrimental effect on reproduction, behavior, health and survival, due to the negative effects on components of the immune system. However, little is known about the effects of chronic sublethal metal exposure on immunity, especially for wildlife. In our study, we examined the constitutive innate immunity of great tit (Parus major) nestlings (N = 234) living in four populations along a metal pollution gradient. For each nestling, we determined the individual metal concentrations (lead, cadmium, arsenic) present in the red blood cells and measured four different innate immune parameters (agglutination, lysis, haptoglobin concentrations and nitric oxide concentrations) to investigate the relationship between metal exposure and immunological condition. While we found significant differences in endogenous metal concentrations among populations with the highest concentrations closest to the pollution source, we did not observe corresponding patterns in our immune measures. However, when evaluating relationships between metal concentrations and immune parameters at the individual level, we found negative effects of lead and, to a lesser extent, arsenic and cadmium on lysis. In addition, high arsenic concentrations appear to elicit inflammation, as reflected by elevated haptoglobin concentrations. Thus despite the lack of a geographic association between pollution and immunity, this type of association was present at the individual level at a very early life stage. The high variation in metal concentrations and immune measures observed within populations indicates a high level of heterogeneity along an existing pollution gradient. Interestingly, we also found substantial within nest variation, for which the sources remain unclear, and which highlights the need of an individual-based approach. - Highlights: • Innate immunity

Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

Science.gov (United States)

Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

2017-05-01

Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO 2 , making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO 2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO 2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO 2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO 2 , indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO 2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

The Relationship of Individual Difference and Group Process Variables with Self-Managed Team Performance: A Field Investigation

National Research Council Canada - National Science Library

Jordan, Mark

2001-01-01

The efficacy of dispositional individual difference team composition and group process variables in explaining team performance was examined for 1,030 military officers working in 92 teams over a 5-week period...

On the tip of the tongue: learning typing and pointing with an intra-oral computer interface.

Science.gov (United States)

Caltenco, Héctor A; Breidegard, Björn; Struijk, Lotte N S Andreasen

2014-07-01

To evaluate typing and pointing performance and improvement over time of four able-bodied participants using an intra-oral tongue-computer interface for computer control. A physically disabled individual may lack the ability to efficiently control standard computer input devices. There have been several efforts to produce and evaluate interfaces that provide individuals with physical disabilities the possibility to control personal computers. Training with the intra-oral tongue-computer interface was performed by playing games over 18 sessions. Skill improvement was measured through typing and pointing exercises at the end of each training session. Typing throughput improved from averages of 2.36 to 5.43 correct words per minute. Pointing throughput improved from averages of 0.47 to 0.85 bits/s. Target tracking performance, measured as relative time on target, improved from averages of 36% to 47%. Path following throughput improved from averages of 0.31 to 0.83 bits/s and decreased to 0.53 bits/s with more difficult tasks. Learning curves support the notion that the tongue can rapidly learn novel motor tasks. Typing and pointing performance of the tongue-computer interface is comparable to performances of other proficient assistive devices, which makes the tongue a feasible input organ for computer control. Intra-oral computer interfaces could provide individuals with severe upper-limb mobility impairments the opportunity to control computers and automatic equipment. Typing and pointing performance of the tongue-computer interface is comparable to performances of other proficient assistive devices, but does not cause fatigue easily and might be invisible to other people, which is highly prioritized by assistive device users. Combination of visual and auditory feedback is vital for a good performance of an intra-oral computer interface and helps to reduce involuntary or erroneous activations.

Studying the variability in the Raman signature of writing pen inks.

Science.gov (United States)

Braz, André; López-López, María; García-Ruiz, Carmen

2014-12-01

This manuscript aims to study the inter and intra brand, model and batch variability in the Raman spectral signature among modern pen inks that will help forensic document examiners during the interpretation process. Results showed that most oil-based samples have similar Raman signatures that are characteristic of the Crystal Violet dye, independently of the brand. Exception was the Pilot samples that use Victoria Pure Blue BO instead. This small inter-brand variability makes oil-based pens difficult to discriminate by brand. On the contrary, gel and liquid-based samples use different colorants such as Rhodamine B, Copper Phthalocyanine, Ethyl Violet and Victoria Blue B. No particular pattern was observed regarding the colorants used by each brand, except the Pilot samples that were the only brand using the Victoria Blue B dye, which is a clear distinct feature. Additionally, the intra-brand variability was also large among gel-based Pilot samples. The small spectral differences observed among several batches of Bic Crystal Medium samples demonstrated that changes were introduced in their chemical formula over the years. The intra-batch variability was small and no spectral differences were observed within batches. This manuscript demonstrates the potential of Raman spectroscopy for discriminating pens inks from different brands and models and even, batches. Additionally, the main colorants used in modern pens were also identified. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Observer variability when evaluating patient movement from electronic portal images of pelvic radiotherapy fields

International Nuclear Information System (INIS)

Geraint Lewis, D.; Ryan, Karen R.; Smith, Cyril W.

2005-01-01

Background and purpose: A study has been performed to evaluate inter-observer variability when assessing pelvic patient movement using an electronic portal imaging device (EPID). Materials and methods: Four patient image sets were used with 3-6 portal images per set. The observer group consisted of nine radiographers with 3-18 months clinical EPID experience. The observers outlined bony landmarks on a digital simulator image and used matching software to evaluate field placement errors (FPEs) on each portal image relative to the reference simulator image. Data were evaluated statistically, using a two-component analysis of variance technique, to quantify both the inter-observer variability in evaluating FPEs and inter-fraction variability in patient position relative to the residuals of the analysis. Intra-observer variability was also estimated using four of the observers carrying out three sets of repeat readings. Results: Eight sets of variance data were analysed, based on FPEs in two orthogonal directions for each of the four patient image sets studied. Initial analysis showed that both inter-observer variation and inter-fraction-patient position variation were statistically significant (P<0.05) in seven of the eight cases evaluated. The averaged root-mean-square (RMS) deviation of the observers from the group mean was 1.1 mm, with a maximum deviation of 5.0 mm recorded for an individual observer. After additional training and re-testing of two of the observers who recorded the largest deviations from the group mean, a subsequent analysis showed the inter-observer variability for the group to be significant in only three of the eight cases, with averaged RMS deviation reduced to 0.5 mm, with a maximum deviation of 2.7 mm. The intra-observer variability was 0.5 mm, averaged over the four observers tested. Conclusions: We have developed a quantitative approach to evaluate inter-observer variability in terms of its statistical significance compared to inter

Inter- and intra-industry variations of capital structure in the Czech manufacturing industry

Directory of Open Access Journals (Sweden)

Pavlína Pinková

2013-01-01

Full Text Available The objective of the paper is to investigate the existence of inter-industry variations in the capital structure of enterprises of the Czech manufacturing industry and to identify the intra-industry causes of these differences. Three measures of capital structure are employed to determine the inter-industry variations. These are total debt ratio, long-term debt and short-term debt ratios. The set of explanatory variables is included to clarify the intra-industry variations. These explanatory variables are size, asset structure, asset utilization, profitability, non-debt tax shield and growth. The paper reports the analysis of capital structure of five distinctive industrial branches, namely the manufacture of beverages, the manufacture of textiles, the manufacture of paper and paper products, the manufacture of chemicals and chemical products, and the manufacture of computer, electronic and optical products. The data come from the financial statements of selected companies and cover a period from 2008 to 2012. The analysis of variance, correlation and regression analyses are used to develop the statistical framework. The paper aims to study the impact of industry and firm characteristics on capital structure choice.

Ambulatory ECG and analysis of heart rate variability in Parkinson's disease

OpenAIRE

Haapaniemi, T; Pursiainen, V; Korpelainen, J; Huikuri, H; Sotaniemi, K; Myllyla, V

2001-01-01

OBJECTIVES—Cardiovascular reflex tests have shown both sympathetic and parasympathetic failure in Parkinson's disease. These tests, however, describe the autonomic responses during a restricted time period and have great individual variability, providing a limited view of the autonomic cardiac control mechanisms. Thus, they do not reflect tonic autonomic regulation. The aim was to examine tonic autonomic cardiovascular regulation in untreated patients with Parkinson's dis...

Structural Variability within Frontoparietal Networks and Individual Differences in Attentional Functions: An Approach Using the Theory of Visual Attention.

Science.gov (United States)

Chechlacz, Magdalena; Gillebert, Celine R; Vangkilde, Signe A; Petersen, Anders; Humphreys, Glyn W

2015-07-29

Visuospatial attention allows us to select and act upon a subset of behaviorally relevant visual stimuli while ignoring distraction. Bundesen's theory of visual attention (TVA) (Bundesen, 1990) offers a quantitative analysis of the different facets of attention within a unitary model and provides a powerful analytic framework for understanding individual differences in attentional functions. Visuospatial attention is contingent upon large networks, distributed across both hemispheres, consisting of several cortical areas interconnected by long-association frontoparietal pathways, including three branches of the superior longitudinal fasciculus (SLF I-III) and the inferior fronto-occipital fasciculus (IFOF). Here we examine whether structural variability within human frontoparietal networks mediates differences in attention abilities as assessed by the TVA. Structural measures were based on spherical deconvolution and tractography-derived indices of tract volume and hindrance-modulated orientational anisotropy (HMOA). Individual differences in visual short-term memory (VSTM) were linked to variability in the microstructure (HMOA) of SLF II, SLF III, and IFOF within the right hemisphere. Moreover, VSTM and speed of information processing were linked to hemispheric lateralization within the IFOF. Differences in spatial bias were mediated by both variability in microstructure and volume of the right SLF II. Our data indicate that the microstructural and macrostrucutral organization of white matter pathways differentially contributes to both the anatomical lateralization of frontoparietal attentional networks and to individual differences in attentional functions. We conclude that individual differences in VSTM capacity, processing speed, and spatial bias, as assessed by TVA, link to variability in structural organization within frontoparietal pathways. Copyright © 2015 Chechlacz et al.

Intra-individual comparison of image contrast in SPIO-enhanced liver MRI at 1.5T and 3.0T

International Nuclear Information System (INIS)

Falkenhausen, Marcus von; Meyer, Carsten; Lutterbey, Goetz; Morakkabati, Nuschin; Bloemer, Renate; Willinek, Winfried A.; Kuhl, Christiane K.; Schild, Hans H.; Walter, Oliver; Gieseke, Juergen

2007-01-01

The purpose of the study was to examine if the higher susceptibility at 3.0 Tesla (T) compared to 1.5 T will affect the contrast in MR imaging of the liver after application of superparamagnetic iron oxide particles (SPIO). The study was approved by our institutional review board and informed consent was obtained. Seventeen healthy volunteers were examined in a prospective, intra-individual comparative study within one day on a 1.5 T and a 3.0 T MRI system. T2 weighted TSE sequences were acquired after bolus injection of a SPIO contrast agent. Image contrast and signal to noise ratio (SNR) were compared between the field strengths. Image contrast was calculated between the liver tissue and the kidneys / spleen / muscles and fluids. The students'T-test was used for statistical analysis. No influence of the higher field strength could be observed on image contrast except for the liver / muscle contrast. This was due to a distinct SNR increase of the muscle tissue at 3.0 T as a result of their relaxation properties. The higher susceptibility at 3.0 T compared to 1.5 T does not translate into a stronger signal attenuation of the SPIO enhanced liver parenchyma. (orig.)

Intra-individual comparison of image contrast in SPIO-enhanced liver MRI at 1.5T and 3.0T

Energy Technology Data Exchange (ETDEWEB)

Falkenhausen, Marcus von; Meyer, Carsten; Lutterbey, Goetz; Morakkabati, Nuschin; Bloemer, Renate; Willinek, Winfried A.; Kuhl, Christiane K.; Schild, Hans H. [University of Bonn, Department of Radiology, Bonn (Germany); Walter, Oliver [Leibniz-Institute for Science Education, Kiel (Germany); Gieseke, Juergen [University of Bonn, Department of Radiology, Bonn (Germany); Philips Medical Systems, Hamburg (Germany)

2007-05-15

The purpose of the study was to examine if the higher susceptibility at 3.0 Tesla (T) compared to 1.5 T will affect the contrast in MR imaging of the liver after application of superparamagnetic iron oxide particles (SPIO). The study was approved by our institutional review board and informed consent was obtained. Seventeen healthy volunteers were examined in a prospective, intra-individual comparative study within one day on a 1.5 T and a 3.0 T MRI system. T2 weighted TSE sequences were acquired after bolus injection of a SPIO contrast agent. Image contrast and signal to noise ratio (SNR) were compared between the field strengths. Image contrast was calculated between the liver tissue and the kidneys / spleen / muscles and fluids. The students'T-test was used for statistical analysis. No influence of the higher field strength could be observed on image contrast except for the liver / muscle contrast. This was due to a distinct SNR increase of the muscle tissue at 3.0 T as a result of their relaxation properties. The higher susceptibility at 3.0 T compared to 1.5 T does not translate into a stronger signal attenuation of the SPIO enhanced liver parenchyma. (orig.)

Seasonal weather-related decision making for cattle production in the Northern Great Plains

Science.gov (United States)

High inter-annual variability of seasonal weather patterns can greatly affect forage and therefore livestock production in the Northern Great Plains. This variability can make it difficult for ranchers to set yearly stocking rates, particularly in advance of the grazing season. To better understand ...

Penultimate Glacial-Interglacial Climate Variability in the Southern Great Plains of North America

Science.gov (United States)

Bartow-Gillies, E.; Maupin, C. R.; Roark, E. B.; Chou, Y. C.; White, K.; Kampen-Lewis, S. V.; Shen, C. C.

2017-12-01

Projections of changes in rainfall under future warming scenarios vary in their sign and intensity over the Southern Great Plains (SGP). A scarcity of local paleoclimate information before the Last Glacial Maximum (LGM) limits our understanding of regional climate responses to changes in mean state and forcing. Here, we present absolutely U/Th-dated oxygen and carbon isotope records from a calcite stalagmite near Georgetown, Texas (30°N, 98°W), spanning 98 to 209 kyr before present (kyr BP). SGP moisture is primarily sourced from the Gulf of Mexico, and precipitation exhibits clear seasonality, with a biannual rainy season divided into late boreal spring and fall. We interpret the oxygen isotopic composition of the stalagmite to reflect changes in rainwater δ18O composition, as well as cave temperature, through time. There are no clear kinetic isotope effects observed within the stalagmite. More negative (positive) δ18O values are a reflection of warmer and wetter (cooler and drier) conditions based on modern observations of rainwater δ18O at the study site. Variations in stalagmite δ13C may be driven by shifts in overlying vegetation type and changes in the rates of karst flow and prior calcite precipitation. The stalagmite records include Marine Isotope Stage (MIS) 5e, an interval where global temperatures may have been as much as 2°C warmer and sea level 4-6 m higher than present. Thus, our δ18O record provides context of unique importance for how SGP hydroclimate may respond to future warming. Prominent features in the δ18O record, including a warm and wet MIS 5e appear to be paced by precession, with the timing of δ18O minima (maxima) broadly consistent with that of maxima (minima) in monthly insolation at 30°N. The δ13C record exhibits a striking similarity to canonical, sawtooth records of glacial-interglacial variability, which suggests Great Plains vegetation communities may be sensitive to the status of Northern Hemisphere glaciation. Our SGP

Intra-chromosomal aberrations observed after high-LET radiation exposure in vivo using a state-of-the-art cytogenetic technique

International Nuclear Information System (INIS)

Mitchell, C.R.; Geard, C.R.; Brenner, D.J.; Hande, P.; Azizova, T.V.; Burak, L.E.; Khokhryakov, V.F.; Vasienko, E.K.

2003-01-01

Multicolor banding fluorescence in situ hybridization (mBAND) was used to investigate the presence of stable intra-chromosomal aberrations in chromosomes 1, 2 and 5 in a population of individuals exposed previously to low and/or high-LET radiation. Peripheral blood lymphocytes were taken from healthy Russian nuclear workers occupationally exposed to plutonium α -particles, γ -rays or both at the Mayak complex from 1949 onwards. Metaphase spreads were produced and chromosomes hybridized with mBAND probes and scored for intra-chromosomal aberrations including inversions and deletions. A large difference between the intra-chromosomal aberration frequencies for the high-plutonium (∼1.1 Gy) and the high- γ exposed (∼1.5 Gy) individuals was observed in all three chromosomes studied (chromosome 1: 1.9 ± 0.5 % (n=7) vs. 0.1 ± 0.1% (n=5); chromosome 2: 1.7 ± 0.4% (n=7) vs. 0 [0 -0.3]% (n=6); chromosome 5: 3.7 ± 0.5 % (n=11) vs. 0.1 ± 0.1 % (n=11) (high-plutonium vs. high-γ exposure)). Controls (n=5) showed very few or no intra-chromosomal aberrations. Significantly fewer aberrations were observed in chromosomes 1 and 2 compared with chromosome 5, studied previously in this cohort, suggesting that intra-chromosomal changes involving chromosomes 1 and 2 may be more lethal to the cell than those involving chromosome 5. The dramatic differences in yields of intra-chromosomal aberrations in high-plutonium exposure relative to low may provide a means of discrimination to estimate both the dose and type of previous radiation exposure in populations

Study of the kinematic variables of unilateral and habitual mastication of healthy individuals.

Science.gov (United States)

Pasinato, Fernanda; Oliveira, Andréia Gussi de; Santos-Couto-Paz, Clarissa C; Zeredo, Jorge Luis Lopes; Bolzan, Geovana de Paula; Macedo, Sergio Bruzadelli; Corrêa, Eliane C R

2017-03-30

To describe and compare the temporal-spatial kinematic variables of mandibular movement during deliberate unilateral and habitual mastication in healthy young-adult individuals. The study sample was composed of eight male healthy volunteers aged 19 to 24 years. The kinematic data were obtained using a motion analysis system - Qualisys Track Manager (QTM) ProReflex MCU. Recordings were performed during deliberate unilateral mastication (UM) and habitual mastication (HM) of firm-consistency gummy candy. The following variables were analyzed: (1) masticatory sequence: duration, number of masticatory cycles, and chewing rate; (2) masticatory cycle: duration, vertical and medial-lateral mandibular range of motion in relation to the skull, and maximum velocity during the opening and closing phases. Data of the variables were compared during UM and HM by the paired t test, and the effect sizes ('d' Cohen) were calculated. Regarding the variables of the masticatory sequence, smaller chewing rate was observed for UM compared with that for HM (1.19±0.21Hz and 1.29±0.16Hz, respectively, p=0.004, d=0.53). Smaller values of maximum velocity during the opening (MU=67.4 mm/s and MH=80.02, p=0.053, d=0.80) and closing (MU=71.77±9.35mm/s and MH=3.51±7mm/s, p=0.014, d=0.79) phases of the masticatory cycle were observed in deliberate unilateral mastication compared with those in habitual mastication. Kinematic variables associated with the sequence and cycle of mastication are influenced by the chewing pattern adopted - deliberate unilateral or habitual.

Investigation of patient, tumour and treatment variables affecting residual motion for respiratory-gated radiotherapy

International Nuclear Information System (INIS)

George, R; Ramakrishnan, V; Siebers, J V; Chung, T D; Keall, P J

2006-01-01

Respiratory gating can reduce the apparent respiratory motion during imaging and treatment; however, residual motion within the gating window remains. Respiratory training can improve respiratory reproducibility and, therefore, the efficacy of respiratory-gated radiotherapy. This study was conducted to determine whether residual motion during respiratory gating is affected by patient, tumour or treatment characteristics. The specific aims of this study were to: (1) identify significant characteristics affecting residual motion, (2) investigate time trends of residual motion over a period of days (inter-session) and (3) investigate time trends of residual motion within the same day (intra-session). Twenty-four lung cancer patients were enrolled in an Institutional Review Board (IRB)-approved protocol. For approximately five sessions, 331 four-minute, respiratory motion traces were acquired with free breathing, audio instructions and audio-visual biofeedback for each patient. The residual motion was quantified by the standard deviation of the displacement within the gating window. The generalized linear model was used to obtain coefficients for each variable within the model and to evaluate the clinical and statistical significance. The statistical significance was determined by a p-value <0.05, while effect sizes of ≥0.1 cm (one standard deviation) were considered clinically significant. This data analysis was applied to patient, tumour and treatment variables. Inter- and intra-session variations were also investigated. The only variable that was significant for both inhale- and exhale-based gating was disease type. In addition, visual-training displacement, breathing type and Karnofsky performance status (KPS) values were significant for inhale-based gating, and dose-per-fraction was significant for exhale-based gating. Temporal respiratory variations within and between sessions were observed for individual patients. However inter- and intra-session analyses did

Investigation of patient, tumour and treatment variables affecting residual motion for respiratory-gated radiotherapy

Energy Technology Data Exchange (ETDEWEB)

George, R [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Ramakrishnan, V [Department of Biostatistics, Virginia Commonwealth University, Richmond, VA (United States); Siebers, J V [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Chung, T D [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Keall, P J [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States)

2006-10-21

Respiratory gating can reduce the apparent respiratory motion during imaging and treatment; however, residual motion within the gating window remains. Respiratory training can improve respiratory reproducibility and, therefore, the efficacy of respiratory-gated radiotherapy. This study was conducted to determine whether residual motion during respiratory gating is affected by patient, tumour or treatment characteristics. The specific aims of this study were to: (1) identify significant characteristics affecting residual motion, (2) investigate time trends of residual motion over a period of days (inter-session) and (3) investigate time trends of residual motion within the same day (intra-session). Twenty-four lung cancer patients were enrolled in an Institutional Review Board (IRB)-approved protocol. For approximately five sessions, 331 four-minute, respiratory motion traces were acquired with free breathing, audio instructions and audio-visual biofeedback for each patient. The residual motion was quantified by the standard deviation of the displacement within the gating window. The generalized linear model was used to obtain coefficients for each variable within the model and to evaluate the clinical and statistical significance. The statistical significance was determined by a p-value <0.05, while effect sizes of {>=}0.1 cm (one standard deviation) were considered clinically significant. This data analysis was applied to patient, tumour and treatment variables. Inter- and intra-session variations were also investigated. The only variable that was significant for both inhale- and exhale-based gating was disease type. In addition, visual-training displacement, breathing type and Karnofsky performance status (KPS) values were significant for inhale-based gating, and dose-per-fraction was significant for exhale-based gating. Temporal respiratory variations within and between sessions were observed for individual patients. However inter- and intra-session analyses did

Prognosis of patients with stage IIIb-IVa squamous cell carcinoma of the cervix following intra-arterial neoadjuvant chemotherapy

International Nuclear Information System (INIS)

Fujiwaki, R.; Maede, Y.; Ohnishi, Y.; Watanabe, Y.; Hata, K.; Miyazaki, K.

1999-01-01

The aim was to determine the long-term prognosis in patients with stage IIIb-IVa squamous cell carcinoma of the cervix who were treated with intra-arterial neoadjuvant chemotherapy (NAC), and to analyze factors related to prognostic value. The authors assessed the disease-free survival of 21 patients with FIGO stage IIIb-IVa squamous cell carcinoma of the cervix treated with intra-arterial NAC followed by irradiation therapy. Before chemotherapy, five factors (age, clinical stage, histologic type, parametrial involvement and serum level of SCC) were evaluated for their correlation with disease-free survival. Univariate Cox's proportional hazard model also demonstrated that age was a significant prognostic factor as a continuous variable. Intra-arterial NAC thus appeared to be effective in treating older patients with stage IIIb-IVa squamous cell carcinoma of the cervix

Balancing renewable on intra day electricity markets

International Nuclear Information System (INIS)

Sokol, R.; Bems, J.

2012-01-01

Intra day electricity markets contribute to facilitate transition from conventional sources to renewable which need to be balanced on real-time basic due to the unpredictable nature of weather. This paper describes the way from regional electricity markets to a single pan-european market model which is target model of the European Commission. Single liquid intra day electricity market where market participants can balance their portfolios is prerequisite to a full utilisation of renewable power sources and a solution for some problems experienced by TSOs with loop and parallel flows from neighbouring countries. Integrated German and French intra day electricity market which uses Flexible Intra day Trading Scheme is described in this paper as a market which could be extended further to the CEE region with very poor liquidity of its local intra day markets. (Authors)

[Development and validation of a questionnaire about the main variables affecting the individual investor's behavior in the Stock Exchange].

Science.gov (United States)

Pascual-Ezama, David; San Martín Castellanos, Rafael; Gil-Gómez de Liaño, Beatriz; Scandroglio, Bárbara

2010-11-01

Development and validation of a questionnaire about the main variables affecting the individual investor's behavior in the Stock Exchange. There is a considerable lack of information about the methodology usually used in most of the studies about individual investor's behavior. The studies reviewed do not show the method used in the selection of the items or the psychometric properties of the questionnaires. Because of the importance of investment in the Stock Exchange nowadays, it seems relevant to obtain a reliable instrument to understand individual investor's behavior in the Stock Exchange. Therefore, the goal of the present work is to validate a questionnaire about the main variables involved in individual investors' behavior in the Stock Exchange. Based on previous studies, we elaborated a questionnaire using the Delphi methodology with a group of experts. The internal consistency (Cronbach alpha=.934) and validity evidence of the questionnaire show that it may be an effective instrument and can be applied with some assurance.

Intra- and inter-observer variation in histological criteria used in age at death determination based on femoral cortical bone

DEFF Research Database (Denmark)

Lynnerup, N; Thomsen, J L; Frohlich, B

1998-01-01

been carried out dealing with the intra- and inter-observer error. Furthermore, when such studies have been completed, the statistical tools for assessing variability have not been adequate. This study presents the results of applying simple quantitative statistics on several counts of microscopic...... elements as observed on photographic images of cortical bone, in order to assess intra- and inter-observer error. Overall, substantial error was present at the level of identifying and counting secondary osteons, osteon fragments and Haversian canals. Only secondary osteons can be reliably identified...

Inter-individual variability in the production of flavan-3-ol colonic metabolites: preliminary elucidation of urinary metabotypes.

Science.gov (United States)

Mena, Pedro; Ludwig, Iziar A; Tomatis, Virginia B; Acharjee, Animesh; Calani, Luca; Rosi, Alice; Brighenti, Furio; Ray, Sumantra; Griffin, Julian L; Bluck, Les J; Del Rio, Daniele

2018-04-03

There is much information on the bioavailability of (poly)phenolic compounds following acute intake of various foods. However, there are only limited data on the effects of repeated and combined exposure to specific (poly)phenol food sources and the inter-individual variability in their bioavailability. This study evaluated the combined urinary excretion of (poly)phenols from green tea and coffee following daily consumption by healthy subjects in free-living conditions. The inter-individual variability in the production of phenolic metabolites was also investigated. Eleven participants consumed both tablets of green tea and green coffee bean extracts daily for 8 weeks and 24-h urine was collected on five different occasions. The urinary profile of phenolic metabolites and a set of multivariate statistical tests were used to investigate the putative existence of characteristic metabotypes in the production of flavan-3-ol microbial metabolites. (Poly)phenolic compounds in the green tea and green coffee bean extracts were absorbed and excreted after simultaneous consumption, with green tea resulting in more inter-individual variability in urinary excretion of phenolic metabolites. Three metabotypes in the production of flavan-3-ol microbial metabolites were tentatively defined, characterized by the excretion of different amounts of trihydroxyphenyl-γ-valerolactones, dihydroxyphenyl-γ-valerolactones, and hydroxyphenylpropionic acids. The selective production of microbiota-derived metabolites from flavan-3-ols and the putative existence of characteristic metabotypes in their production represent an important development in the study of the bioavailability of plant bioactives. These observations will contribute to better understand the health effects and individual differences associated with consumption of flavan-3-ols, arguably the main class of flavonoids in the human diet.

Intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injuries.

Science.gov (United States)

Wangensteen, Arnlaug; Tol, Johannes L; Roemer, Frank W; Bahr, Roald; Dijkstra, H Paul; Crema, Michel D; Farooq, Abdulaziz; Guermazi, Ali

2017-04-01

To assess and compare the intra- and interrater reliability of three different MRI grading and classification systems after acute hamstring injury. Male athletes (n=40) with clinical diagnosis of acute hamstring injury and MRI ≤5days were selected from a prospective cohort. Two radiologists independently evaluated the MRIs using standardised scoring form including the modified Peetrons grading system, the Chan acute muscle strain injury classification and the British Athletics Muscle Injury Classification. Intra-and interrater reliability was assessed with linear weighted kappa (κ) or unweighted Cohen's κ and percentage agreement was calculated. We observed 'substantial' to 'almost perfect' intra- (κ range 0.65-1.00) and interrater reliability (κ range 0.77-1.00) with percentage agreement 83-100% and 88-100%, respectively, for severity gradings, overall anatomical sites and overall classifications for the three MRI systems. We observed substantial variability (κ range -0.05 to 1.00) for subcategories within the Chan classification and the British Athletics Muscle Injury Classification, however, the prevalence of positive scorings was low for some subcategories. The modified Peetrons grading system, overall Chan classification and overall British Athletics Muscle Injury Classification demonstrated 'substantial' to 'almost perfect' intra- and interrater reliability when scored by experienced radiologists. The intra- and interrater reliability for the anatomical subcategories within the classifications remains unclear. Copyright © 2017 Elsevier B.V. All rights reserved.

When one size does not fit all: a simple statistical method to deal with across-individual variations of effects.

Science.gov (United States)

Vindras, Philippe; Desmurget, Michel; Baraduc, Pierre

2012-01-01

In science, it is a common experience to discover that although the investigated effect is very clear in some individuals, statistical tests are not significant because the effect is null or even opposite in other individuals. Indeed, t-tests, Anovas and linear regressions compare the average effect with respect to its inter-individual variability, so that they can fail to evidence a factor that has a high effect in many individuals (with respect to the intra-individual variability). In such paradoxical situations, statistical tools are at odds with the researcher's aim to uncover any factor that affects individual behavior, and not only those with stereotypical effects. In order to go beyond the reductive and sometimes illusory description of the average behavior, we propose a simple statistical method: applying a Kolmogorov-Smirnov test to assess whether the distribution of p-values provided by individual tests is significantly biased towards zero. Using Monte-Carlo studies, we assess the power of this two-step procedure with respect to RM Anova and multilevel mixed-effect analyses, and probe its robustness when individual data violate the assumption of normality and homoscedasticity. We find that the method is powerful and robust even with small sample sizes for which multilevel methods reach their limits. In contrast to existing methods for combining p-values, the Kolmogorov-Smirnov test has unique resistance to outlier individuals: it cannot yield significance based on a high effect in one or two exceptional individuals, which allows drawing valid population inferences. The simplicity and ease of use of our method facilitates the identification of factors that would otherwise be overlooked because they affect individual behavior in significant but variable ways, and its power and reliability with small sample sizes (<30-50 individuals) suggest it as a tool of choice in exploratory studies.

When one size does not fit all: a simple statistical method to deal with across-individual variations of effects.

Directory of Open Access Journals (Sweden)

Philippe Vindras

Full Text Available In science, it is a common experience to discover that although the investigated effect is very clear in some individuals, statistical tests are not significant because the effect is null or even opposite in other individuals. Indeed, t-tests, Anovas and linear regressions compare the average effect with respect to its inter-individual variability, so that they can fail to evidence a factor that has a high effect in many individuals (with respect to the intra-individual variability. In such paradoxical situations, statistical tools are at odds with the researcher's aim to uncover any factor that affects individual behavior, and not only those with stereotypical effects. In order to go beyond the reductive and sometimes illusory description of the average behavior, we propose a simple statistical method: applying a Kolmogorov-Smirnov test to assess whether the distribution of p-values provided by individual tests is significantly biased towards zero. Using Monte-Carlo studies, we assess the power of this two-step procedure with respect to RM Anova and multilevel mixed-effect analyses, and probe its robustness when individual data violate the assumption of normality and homoscedasticity. We find that the method is powerful and robust even with small sample sizes for which multilevel methods reach their limits. In contrast to existing methods for combining p-values, the Kolmogorov-Smirnov test has unique resistance to outlier individuals: it cannot yield significance based on a high effect in one or two exceptional individuals, which allows drawing valid population inferences. The simplicity and ease of use of our method facilitates the identification of factors that would otherwise be overlooked because they affect individual behavior in significant but variable ways, and its power and reliability with small sample sizes (<30-50 individuals suggest it as a tool of choice in exploratory studies.

Intra and Inter-Rater Reliability of Screening for Movement Impairments: Movement Control Tests from The Foundation Matrix

Science.gov (United States)

Mischiati, Carolina R.; Comerford, Mark; Gosford, Emma; Swart, Jacqueline; Ewings, Sean; Botha, Nadine; Stokes, Maria; Mottram, Sarah L.

2015-01-01

Pre-season screening is well established within the sporting arena, and aims to enhance performance and reduce injury risk. With the increasing need to identify potential injury with greater accuracy, a new risk assessment process has been produced; The Performance Matrix (battery of movement control tests). As with any new method of objective testing, it is fundamental to establish whether the same results can be reproduced between examiners and by the same examiner on consecutive occasions. This study aimed to determine the intra-rater test re-test and inter-rater reliability of tests from a component of The Performance Matrix, The Foundation Matrix. Twenty participants were screened by two experienced musculoskeletal therapists using nine tests to assess the ability to control movement during specific tasks. Movement evaluation criteria for each test were rated as pass or fail. The therapists observed participants real-time and tests were recorded on video to enable repeated ratings four months later to examine intra-rater reliability (videos rated two weeks apart). Overall test percentage agreement was 87% for inter-rater reliability; 98% Rater 1, 94% Rater 2 for test re-test reliability; and 75% for real-time versus video. Intraclass-correlation coefficients (ICCs) were excellent between raters (0.81) and within raters (Rater 1, 0.96; Rater 2, 0.88) but poor for real-time versus video (0.23). Reliability for individual components of each test was more variable: inter-rater, 68-100%; intra-rater, 88-100% Rater 1, 75-100% Rater 2; and real-time versus video 31-100%. Cohen’s Kappa values for inter-rater reliability were 0.0-1.0; intra-rater 0.6-1.0 for Rater 1; -0.1-1.0 for Rater 2; and -0.1-1 for real-time versus video. It is concluded that both inter and intra-rater reliability of tests in The Foundation Matrix are acceptable when rated by experienced therapists. Recommendations are made for modifying some of the criteria to improve reliability where

Intra-Industry Trade in Tourism Services

Directory of Open Access Journals (Sweden)

Nuno Carlos LEITÃO

2011-06-01

Full Text Available Usually the tourism flows are explained by demand, economic growth, and revealed comparative advantage (neoclassic trade theory.This manuscript examines the link between intra-industry trade and international tourism flows. We have examined the Portuguese intra-industry trade in this sector. The analysis apply the static (Grubel and Lloyd and dynamic index (Brülhart. Our results show that the tourism services are important for a small economy such as Portugal. The intra-industry trade is very significant between Portugal and the following countries: Spain, USA, Italy, Greece, Turkey and Canada.

The Intra Industry Trade between Portugal European Union, Portugal Spain, Portugal-France, Portugal Germany, Portugal-Ireland, Portugal-Greece and Portugal-Netherlands - a Dynamic Panel Data Analysis (1996 2000)

OpenAIRE

Horácio Faustino; Nuno Carlos Leitão

2005-01-01

PortugalÂ’s main trade partners have been Spain, Germany and France. In this paper we analyse the intra industry trade in the manufacturing industry between Portugal Spain, Portugal-France, Portugal Germany, Portugal-Ireland and Portugal-Greece. We also present the results of intra industry trade (IIT) between Portugal and the European Union. The innovation, technological progress, human capital, and scale economies are some of the explicative variables of the intra industry trade phenomena. ...

Hydrologic variability in the Red River of the North basin at the eastern margin of the northern Great Plains

International Nuclear Information System (INIS)

Wiche, G.J.

1991-01-01

The temporal and spatial variations in streamflow in the Red River of the North basin on the eastern margin of the Great Plains are described and related to the various climatic conditions associated with the flows. The Red River drains about 290,000 square kilometers in parts of Minnesota, South Dakota, North Dakota, Saskatchewan and Manitoba, and a 200 year flood history is available from documents of fur traders, explorers and missionaries, as well as from gauging-station records. The coefficient of variation of mean annual streamflow ranges from ca 110% for streams in the southern and western parts of the Assiniboine River basin to ca 50% for streams along the eastern margin of the Red River of the North basin. Decadal streamflow variability is great in the Red River of the North basin, with mean annual streamflow for the 10 years ending 1940 of 489 cubic hectometers and for the 10 years ending 1975 of 3,670 cubic hectometers. Construction of the Rafferty Reservoir on the Souris River and the Almeda Reservoir on Moose Mountain Creek will cause changes in water quality in the Souris River, with most problems occurring during protracted low flow conditions

variability in foliar phenolic composition of several quercus species in northern mexico

International Nuclear Information System (INIS)

Salazar, J.A.A.; Antuna, E.M.; Abarca, N.A.; Alvarado, E.A.D.

2015-01-01

Quantitative and qualitative composition of the foliar phenolic compounds were investigated in 81 individual specimens of several white oak species (Quercus spp.). The trees were growing in twelve locations in Durango, Mexico. The phenol profiles were determined by HPLC-DAD and a Folin-Ciocateuprocedure. The results revealed that: (i) the foliar phenol profiles of all species analysed were complex and formed by 6 to 30 compounds, (ii) the flavonols mostly quercetin glycoside, isorhamnetin glycoside, kaempferol glycoside and phenolic acids were the main identified compounds, (iii) there was a high intra and inter-specific variability in the foliar phenol profiles both at the quantitative and qualitative levels, and (iv) the foliar phenol profiles indicated a slight species-specific tendency for phenols to be accumulated, although this was not clearly distinguished. Significant differences (P < 0.05) in the content and composition of the foliar flavonoids between species were observed due to the large environmental and soil conditions variability between localities. (author)

Correlation between Helicobacter Pylori Infection and Intra Ocular Pressure

Directory of Open Access Journals (Sweden)

Hatamizadeh

2012-02-01

Full Text Available Introduction: Glaucoma is one of the most common causes of blindness. It is estimated that more than 60 million people suffer from this disease of all over the world. In other hand helicobacter pylori is a gram negative bacillus that is reported in some extra-gastrointestinal system diseases recently. This study is designed to determine the association between helicobacter pylori infection and intra-ocular pressure. Methods: This was an analytical cross-sectional study that was conducted on 74 persons who were randomly selected after referring to endoscopy ward of Shohadaye Kargar hospital of Yazd in 2009. Data was analyzed by Mann-Whitney U and fisher exact tests using SPSS software (ver16. Results: Mean of intra-ocular pressure in positive helicobacter pylori group was more than negative helicobacter pylori group but there was no significant relationship (P value > 0.05, also there was no significant relationship between helicobacter pylori infection and diabetes, hypertension, hypothyroidism and hyperthyroidism (P value > 0.05. Conclusion: According to the results, more detailed studies with larger sample size are required for more reliable decisions also considering the confounder variables can help us to determine the common risk factors of these two outcomes.

Estimating the Celestial Reference Frame via Intra-Technique Combination

Science.gov (United States)

Iddink, Andreas; Artz, Thomas; Halsig, Sebastian; Nothnagel, Axel

2016-12-01

One of the primary goals of Very Long Baseline Interferometry (VLBI) is the determination of the International Celestial Reference Frame (ICRF). Currently the third realization of the internationally adopted CRF, the ICRF3, is under preparation. In this process, various optimizations are planned to realize a CRF that does not benefit only from the increased number of observations since the ICRF2 was published. The new ICRF can also benefit from an intra-technique combination as is done for the Terrestrial Reference Frame (TRF). Here, we aim at estimating an optimized CRF by means of an intra-technique combination. The solutions are based on the input to the official combined product of the International VLBI Service for Geodesy and Astrometry (IVS), also providing the radio source parameters. We discuss the differences in the setup using a different number of contributions and investigate the impact on TRF and CRF as well as on the Earth Orientation Parameters (EOPs). Here, we investigate the differences between the combined CRF and the individual CRFs from the different analysis centers.

Intra-abdominal fat measurement by ultrasonography: association with anthropometry and metabolic syndrome in adolescents.

Science.gov (United States)

Novais, Rommel L R; Café, Ana Carolina C; Morais, Aisha A; Bila, Wendell C; Santos, Gilson D da S; Lopes, Carlos Alexandre de O; Belo, Vinícius S; Romano, Márcia Christina C; Lamounier, Joel A

2018-04-27

To associate intra-abdominal fat thickness measured by ultrasonography to the factors related to metabolic syndrome and to determine cutoff points of intra-abdominal fat measurement associated with a greater chance of metabolic syndrome in adolescents. This was a cross-sectional study, with 423 adolescents from public schools. Intra-abdominal fat was measured by ultrasonography. Anthropometric data were collected, and biochemical analyses were performed. Intra-abdominal fat was measured by ultrasonography, showing a statistically significant association with the diagnosis of metabolic syndrome (p=0.037), body mass index (p<0.001), elevated triglyceride levels (p=0.012), decreased plasma HDL levels (p=0.034), and increased systemic blood pressure values (p=0.023). Cutoff values of intra-abdominal fat thickness measurements were calculated by ultrasound to estimate the individuals most likely to develop metabolic syndrome. In the logistic regression models, the cutoff values that showed the highest association with metabolic syndrome in males were 4.50, 5.35, 5.46, 6.24, and 6.50cm for the ages of 14, 15, 16, 17, and 18/19 years, respectively. In the female gender, the cutoff values defined for the same age groups were 4.46, 4.55, 4.45, 4.90, and 6.46cm. In an overall analysis using the ROC curve, without gender and age stratification, the cut-off of 3.67cm showed good sensitivity, but low specificity. Ultrasonography is a useful method to estimate intra-abdominal adipose tissue in adolescents, which is associated with the main factors related to obesity and metabolic syndrome. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Variability of vascular CT measurement techniques used in the assessment abdominal aortic aneurysms

International Nuclear Information System (INIS)

England, Andrew; Niker, Amanda; Redmond, Claire

2010-01-01

Purpose: The aim of this project is to assess the variability of six CT measurement techniques for sizing abdominal aortic aneurysms (AAAs). Method: 37 CT scans with known AAAs were loaded on to a departmental picture archiving and communication system (PACS). A team of three observers, with experience in aortic CT measurements and the PACS performed a series of 2D and 3D measurements on the abdominal aorta. Each observer was asked to measure 3 quantities; anterior-posterior AAA diameter, maximum oblique AAA diameter, maximum aneurysm area using both 2D and 3D techniques. In order to test intra-observer variability each observer was asked to repeat their measurements. All measurements were taken using electronic callipers, under standardised viewing conditions using previously calibrated equipment. 3D measurements were conducted using a computer generated central luminal line (CLL). All measurements for this group were taken perpendicular to the CLL. Results: A total of 972 independent measurements were recorded by three observers. Mean intra-observer variability was lower for 2D diameter measurements (AP 1.3 ± 1.6 mm; 2D Oblique 1.2 ± 1.3 mm) and 2D areas (0.7 ± 1.3 cm 2 ) when compared to inter-observer variability (AP 1.7 ± 1.9 mm; Oblique 1.6 ± 1.7 mm; area 1.1 ± 1.5 cm 2 ). When comparing 2D with 3D measurements, differences were comparable except for 3D AP diameter and area which had lower inter-observer variability than their 2D counterparts (AP 2D 1.7 ± 1.9 mm, 3D 1.3 ± 1.3 mm; area 2D 1.1 ± 1.5 cm 2 , 3D 0.7 ± 0.7 cm 2 ). 3D area measurement was the only technique which had equal variability for intra- and inter-observer measurements. Overall observer variability for the study was good with 94-100% of all paired measurements within 5.00 mm/cm 2 or less. Using Pitman's test it can be confirmed that area measurements in the 3D plane have the least variability (r = 0.031) and 3D oblique measurements have the highest variability (r = 0

Intra-household relations and treatment decision-making for childhood illness: a Kenyan case study.

Science.gov (United States)

Molyneux, C S; Murira, G; Masha, J; Snow, R W

2002-01-01

This study, conducted on the Kenyan coast, assesses the effect of intra-household relations on maternal treatment-seeking. Rural and urban Mijikenda mothers' responses to childhood fevers in the last 2 weeks (n=317), and to childhood convulsions in the previous year (n=43), were documented through survey work. The intra-household relations and decision-making dynamics surrounding maternal responses were explored through in-depth individual and group interviews, primarily with women (n=223). Responses to convulsions were more likely than responses to fevers to include a healer consultation (p<0.0001), and less likely to include the purchase of over-the-counter medications (p<0.0001). Mothers received financial or advisory assistance from others in 71% (n=236) of actions taken outside the household in response to fevers. In-depth interviews suggested that general agreement on appropriate therapy results in relatively few intra-household conflicts over the treatment of fevers. Disputes over perceived cause and appropriate therapy of convulsions, however, highlighted the importance of age, gender and relationship to household head in intra-household relations and treatment decision-making. Although mothers' treatment-seeking preferences are often circumscribed by these relations, a number of strategies can be drawn upon to circumvent 'inappropriate' decisions, sometimes with implications for future household responses to similar syndromes. The findings highlight the complexity of intra-household relations and treatment decision-making dynamics. Tentative implications for interventions aimed at improving the home management of malaria, and for further research, are presented.

Intra-articular therapies for osteoarthritis.

Science.gov (United States)

Yu, Shirley P; Hunter, David J

2016-10-01

Conventional medical therapies for osteoarthritis are mainly palliative in nature, aiming to control pain and symptoms. Traditional intra-articular therapies are not recommended in guidelines as first line therapy, but are potential alternatives, when conventional therapies have failed. Current and future intra-articular drug therapies for osteoarthritis are highlighted, including corticosteroids, hyaluronate, and more controversial treatments marketed commercially, namely platelet rich plasma and mesenchymal cell therapy. Intraarticular disease modifying osteoarthritis drugs are the future of osteoarthritis treatments, aiming at structural modification and altering the disease progression. Interleukin-1β inhibitor, bone morphogenic protein-7, fibroblast growth factor 18, bradykinin B2 receptor antagonist, human serum albumin, and gene therapy are discussed in this review. The evolution of drug development in osteoarthritis is limited by the ability to demonstrate effect. High quality trials are required to justify the use of existing intra-articular therapies and to advocate for newer, promising therapies. Challenges in osteoarthritis therapy research are fundamentally related to the complexity of the pathological mechanisms of osteoarthritis. Novel drugs offer hope in a disease with limited medical therapy options. Whether these future intra-articular therapies will provide clinically meaningful benefits, remains unknown.

Growth and variability in health plan premiums in the individual insurance market before the Affordable Care Act.

Science.gov (United States)

Gruber, Jonathan

2014-06-01

Before we can evaluate the impact of the Affordable Care Act on health insurance premiums in the individual market, it is critical to understand the pricing trends of these premiums before the implementation of the law. Using rates of increase in the individual insurance market collected from state regulators, this issue brief documents trends in premium growth in the pre-ACA period. From 2008 to 2010, premiums grew by 10 percent or more per year. This growth was also highly variable across states, and even more variable across insurance plans within states. The study suggests that evaluating trends in premiums requires looking across a broad array of states and plans, and that policymakers must examine how present and future changes in premium rates compare with the more than 10 percent per year premium increases in the years preceding health reform.

Guide to intra-arterial infusion chemotherapy for pancreatic cancers (draft text)

International Nuclear Information System (INIS)

2012-01-01

Pancreatic cancer is one of most malignant solid tumors. Trans-arterial infusion chemotherapy has been used for the inoperable pancreatic cancers. The local drug concentration in intra-arterial infusion chemotherapy is much higher than that in intravenous chemotherapy. Thus, a better therapeutic effect can be surely achieved, the disease-related symptoms can be well improved, the patient's survival time can be markedly prolonged, and the liver metastases can be effectively reduced. This paper aims to suggest a more detailed and standardized therapeutic scheme to perform intra-arterial infusion chemotherapy for inoperable pancreatic cancers, focusing on the relevant concept, contraindications, indications, preoperative preparation, methods of operation, postoperative treatment, the prevention and treatment of complications, etc. The scheme will help domestic interventional physicians to make reasonable decisions in their clinical practice. Of course, the scheme proposed here is not a mandatory standard, and it can not resolve all the problems which might be encountered in employing intra-arterial infusion chemotherapy for patients with inoperable pancreatic cancer. Therefore, the interventional physicians should fully understand the most useful medical evidence of a given patient and sincerely take the patient's own will into consideration before an individualized and reasonable therapeutic plan is able to be worked out. (authors)

To be so bold: boldness is repeatable and related to within individual behavioural variability in North Island robins.

Science.gov (United States)

He, Ruchuan; Pagani-Núñez, Emilio; Chevallier, Clément; Barnett, Craig R A

2017-07-01

Behavioural research traditionally focusses on the mean responses of a group of individuals rather than variation in behaviour around the mean or among individuals. However, examining the variation in behaviour among and within individuals may also yield important insights into the evolution and maintenance of behaviour. Repeatability is the most commonly used measure of variability among individuals in behavioural research. However, there are other forms of variation within populations that have received less attention. One such measure is intraindividual variation in behaviour (IIV), which is a short-term fluctuation of within-individual behaviour. Such variation in behaviour might be important during interactions because it could decrease the ability of conspecific and heterospecific individuals to predict the behaviour of the subject, thus increasing the cost of the interaction. In this experiment, we made repeated measures of the latency of North Island robins to attack a prey in a novel situation (a form of boldness) and examined (i) repeatability of boldness (the propensity to take a risk), (ii) IIV of boldness, and (iii) whether there was a significant relationship between these two traits (a behavioural syndrome). We found that boldness was highly repeatable, that there were high levels of IIV in boldness, and that there was a negative relationship between boldness and IIV in boldness. This suggests that despite high levels of repeatability for this behaviour, there were also still significant differences in IIV among different individuals within the population. Moreover, bolder individuals had significantly less IIV in their boldness, which suggests that they were forming routines (which reduces behavioural variability) compared to shyer individuals. Our results definitively demonstrate that IIV itself varies across individuals and is linked with key behavioural traits, and we argue for the importance of future studies aimed at understanding its causes

Intra-lesional spatial correlation of static and dynamic FET-PET parameters with MRI-based cerebral blood volume in patients with untreated glioma.

Science.gov (United States)

Göttler, Jens; Lukas, Mathias; Kluge, Anne; Kaczmarz, Stephan; Gempt, Jens; Ringel, Florian; Mustafa, Mona; Meyer, Bernhard; Zimmer, Claus; Schwaiger, Markus; Förster, Stefan; Preibisch, Christine; Pyka, Thomas

2017-03-01

18 F-fluorethyltyrosine-(FET)-PET and MRI-based relative cerebral blood volume (rCBV) have both been used to characterize gliomas. Recently, inter-individual correlations between peak static FET-uptake and rCBV have been reported. Herein, we assess the local intra-lesional relation between FET-PET parameters and rCBV. Thirty untreated glioma patients (27 high-grade) underwent simultaneous PET/MRI on a 3 T hybrid scanner obtaining structural and dynamic susceptibility contrast sequences. Static FET-uptake and dynamic FET-slope were correlated with rCBV within tumour hotspots across patients and intra-lesionally using a mixed-effects model to account for inter-individual variation. Furthermore, maximal congruency of tumour volumes defined by FET-uptake and rCBV was determined. While the inter-individual relationship between peak static FET-uptake and rCBV could be confirmed, our intra-lesional, voxel-wise analysis revealed significant positive correlations (median r = 0.374, p dynamic FET-PET variance and maximal overlap of respective tumour volumes was 37% on average. Our results show that the relation between peak values of MR-based rCBV and static FET-uptake can also be observed intra-individually on a voxel basis and also applies to a dynamic FET parameter, possibly determining hotspots of higher biological malignancy. However, just a small part of the FET-PET signal variance is explained by rCBV and tumour volumes determined by the two modalities showed only moderate overlap. These findings indicate that FET-PET and MR-based rCBV provide both congruent and complimentary information on glioma biology.

Intra-Tumour Signalling Entropy Determines Clinical Outcome in Breast and Lung Cancer

Science.gov (United States)

Banerji, Christopher R. S.; Severini, Simone; Caldas, Carlos; Teschendorff, Andrew E.

2015-01-01

The cancer stem cell hypothesis, that a small population of tumour cells are responsible for tumorigenesis and cancer progression, is becoming widely accepted and recent evidence has suggested a prognostic and predictive role for such cells. Intra-tumour heterogeneity, the diversity of the cancer cell population within the tumour of an individual patient, is related to cancer stem cells and is also considered a potential prognostic indicator in oncology. The measurement of cancer stem cell abundance and intra-tumour heterogeneity in a clinically relevant manner however, currently presents a challenge. Here we propose signalling entropy, a measure of signalling pathway promiscuity derived from a sample’s genome-wide gene expression profile, as an estimate of the stemness of a tumour sample. By considering over 500 mixtures of diverse cellular expression profiles, we reveal that signalling entropy also associates with intra-tumour heterogeneity. By analysing 3668 breast cancer and 1692 lung adenocarcinoma samples, we further demonstrate that signalling entropy correlates negatively with survival, outperforming leading clinical gene expression based prognostic tools. Signalling entropy is found to be a general prognostic measure, valid in different breast cancer clinical subgroups, as well as within stage I lung adenocarcinoma. We find that its prognostic power is driven by genes involved in cancer stem cells and treatment resistance. In summary, by approximating both stemness and intra-tumour heterogeneity, signalling entropy provides a powerful prognostic measure across different epithelial cancers. PMID:25793737

Intra-tumour signalling entropy determines clinical outcome in breast and lung cancer.

Directory of Open Access Journals (Sweden)

Christopher R S Banerji

2015-03-01

Full Text Available The cancer stem cell hypothesis, that a small population of tumour cells are responsible for tumorigenesis and cancer progression, is becoming widely accepted and recent evidence has suggested a prognostic and predictive role for such cells. Intra-tumour heterogeneity, the diversity of the cancer cell population within the tumour of an individual patient, is related to cancer stem cells and is also considered a potential prognostic indicator in oncology. The measurement of cancer stem cell abundance and intra-tumour heterogeneity in a clinically relevant manner however, currently presents a challenge. Here we propose signalling entropy, a measure of signalling pathway promiscuity derived from a sample's genome-wide gene expression profile, as an estimate of the stemness of a tumour sample. By considering over 500 mixtures of diverse cellular expression profiles, we reveal that signalling entropy also associates with intra-tumour heterogeneity. By analysing 3668 breast cancer and 1692 lung adenocarcinoma samples, we further demonstrate that signalling entropy correlates negatively with survival, outperforming leading clinical gene expression based prognostic tools. Signalling entropy is found to be a general prognostic measure, valid in different breast cancer clinical subgroups, as well as within stage I lung adenocarcinoma. We find that its prognostic power is driven by genes involved in cancer stem cells and treatment resistance. In summary, by approximating both stemness and intra-tumour heterogeneity, signalling entropy provides a powerful prognostic measure across different epithelial cancers.

Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose.

Science.gov (United States)

Wenz, Holger; Maros, Máté E; Meyer, Mathias; Förster, Alex; Haubenreisser, Holger; Kurth, Stefan; Schoenberg, Stefan O; Flohr, Thomas; Leidecker, Christianne; Groden, Christoph; Scharf, Johann; Henzler, Thomas

2015-01-01

To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT) spiral cranial CT (cCT) to a sequential 4-slice Multi-Slice-CT (MSCT) while maintaining identical intra-individual radiation dose levels. 35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP) and 3rd-generation iterative reconstruction (IR) algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR) being subsequently calculated. Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (pspiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels.

Individual differences in ethanol locomotor sensitization are associated with dopamine D1 receptor intra-cellular signaling of DARPP-32 in the nucleus accumbens.

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Karina Possa Abrahao

Full Text Available In mice there are clear individual differences in the development of behavioral sensitization to ethanol, a progressive potentiation of its psychomotor stimulant effect. Variability in the behavioral responses to ethanol has been associated with alcohol preference. Here we investigated if the functional hyperresponsiveness of D1 receptors observed in ethanol sensitized mice leads to an increased activation of DARPP-32, a central regulatory protein in medium spiny neurons, in the nucleus accumbens - a brain region known to play a role in drug reinforcement. Swiss Webster mice received ethanol (2.2 g/kg/day or saline i.p. administrations for 21 days and were weekly evaluated regarding their locomotor activity. From those treated with ethanol, the 33% with the highest levels of locomotor activity were classified as "sensitized" and the 33% with the lowest levels as "non-sensitized". The latter presented similar locomotor levels to those of saline-treated mice. Different subgroups of mice received intra-accumbens administrations of saline and, 48 h later, SKF-38393, D1 receptor agonist 0.1 or 1 µg/side. Indeed, sensitized mice presented functional hyperresponsiveness of D1 receptors in the accumbens. Two weeks following the ethanol treatment, other subgroups received systemic saline or SKF 10 mg/kg, 20 min before the euthanasia. The nucleus accumbens were dissected for the Western Blot analyses of total DARPP-32 and phospho-Thr34-DARPP-32 expression. D1 receptor activation induced higher phospho-Thr34-DARPP-32 expression in sensitized mice than in non-sensitized or saline. The functionally hyperresponsiveness of D1 receptors in the nucleus accumbens is associated with an increased phospho-Thr34-DARPP-32 expression after D1 receptor activation. These data suggest that an enduring increase in the sensitivity of the dopamine D1 receptor intracellular pathway sensitivity represents a neurobiological correlate associated with the development of

Inter-Individual Variability in Human Response to Low-Dose Ionizing Radiation, Final Report

International Nuclear Information System (INIS)

Rocke, David

2016-01-01

In order to investigate inter-individual variability in response to low-dose ionizing radiation, we are working with three models, 1) in-vivo irradiated human skin, for which we have a realistic model, but with few subjects, all from a previous project, 2) ex-vivo irradiated human skin, for which we also have a realistic model, though with the limitations involved in keeping skin pieces alive in media, and 3) MatTek EpiDermFT skin plugs, which provides a more realistic model than cell lines, which is more controllable than human samples.

Inter-Individual Variability in Human Response to Low-Dose Ionizing Radiation, Final Report

Energy Technology Data Exchange (ETDEWEB)

Rocke, David [Univ. of California, Davis, CA (United States)

2016-08-01

In order to investigate inter-individual variability in response to low-dose ionizing radiation, we are working with three models, 1) in-vivo irradiated human skin, for which we have a realistic model, but with few subjects, all from a previous project, 2) ex-vivo irradiated human skin, for which we also have a realistic model, though with the limitations involved in keeping skin pieces alive in media, and 3) MatTek EpiDermFT skin plugs, which provides a more realistic model than cell lines, which is more controllable than human samples.

Context-sensitive intra-class clustering

KAUST Repository

Yu, Yingwei

2014-02-01

This paper describes a new semi-supervised learning algorithm for intra-class clustering (ICC). ICC partitions each class into sub-classes in order to minimize overlap across clusters from different classes. This is achieved by allowing partitioning of a certain class to be assisted by data points from other classes in a context-dependent fashion. The result is that overlap across sub-classes (both within- and across class) is greatly reduced. ICC is particularly useful when combined with algorithms that assume that each class has a unimodal Gaussian distribution (e.g., Linear Discriminant Analysis (LDA), quadratic classifiers), an assumption that is not always true in many real-world situations. ICC can help partition non-Gaussian, multimodal distributions to overcome such a problem. In this sense, ICC works as a preprocessor. Experiments with our ICC algorithm on synthetic data sets and real-world data sets indicated that it can significantly improve the performance of LDA and quadratic classifiers. We expect our approach to be applicable to a broader class of pattern recognition problems where class-conditional densities are significantly non-Gaussian or multi-modal. © 2013 Elsevier Ltd. All rights reserved.

INTRA - Maintenance and Validation. Final Report

International Nuclear Information System (INIS)

Edlund, Ove; Jahn, Hermann; Yitbarek, Z.

2002-05-01

The INTRA code is specified by the ITER Joint Central Team and the European Community as a reference code for safety analyses of Tokamak type fusion reactors. INTRA has been developed by GRS and Studsvik EcoSafe to analyse integrated behaviours such as pressurisation, chemical reactions and temperature transients inside the plasma chamber and adjacent rooms, following postulated accidents, e.g. ingress of coolant water or air. Important results of the ICE and EVITA experiments, which became available early 2001, were used to validate and improve specific INTRA models. Large efforts were spent on the behaviour of water and steam injection into a low-pressure volumes at high temperature as well as on the modelling of boiling of water in contact with hot surfaces. As a result of this a new version, INTRA/Mod4, was documented and issued. The work included implementation and validation of selected physical models in the code, maintaining code versions, preparation review and distribution of code documents, and monitoring of the code related activities being performed by the GRS under a separate contract. The INTRA/Mod4 Manual and Code Description is documented in four volumes: Volume 1 - Physical Modelling, Volume 2 - User's Manual, Volume 3 -Code Structure and Volume 4 - Validation

Impact of meander geometry and stream flow events on residence times and solute transport in the intra-meander flow

Science.gov (United States)

Nasir Mahmood, Muhammad; Schmidt, Christian; Trauth, Nico

2017-04-01

Stream morphological features, in combination with hydrological variability play a key role in water and solute exchange across surface and subsurface waters. Meanders are prominent morphological features within stream systems which exhibit unique hydrodynamics. The water surface elevation difference across the inner bank of a meander induces lateral hyporheic exchange within the intra-meander region. This hyporheic flow is characterized by considerably prolonged flow paths and residence times (RT) compared to smaller scales of hyporheic exchange. In this study we examine the impact of different meander geometries on the intra-meander hyporheic flow field and solute mobilization under both steady state and transient flow conditions. We developed a number of artificial meander shape scenarios, representing various meander evolution stages, ranging from a typical initial to advanced stage (near cut off ) meander. Three dimensional steady state numerical groundwater flow simulations including the unsaturated zone were performed for the intra-meander region. The meandering stream was implemented in the model by adjusting the top layers of the modelling domain to the streambed elevation and assigning linearly decreasing head boundary conditions to the streambed cells. Residence times for the intra-meander region were computed by advective particle tracking across the inner bank of meander. Selected steady state cases were extended to transient flow simulations to evaluate the impact of stream discharge events on the temporal behavior of the water exchange and solute transport in the intra-meander region. The transient stream discharge was simulated for a number of discharge events of variable duration and peak height using the surface water model HEC-RAS. Transient hydraulic heads obtained from the surface water model were applied as transient head boundary conditions to the streambed cells of the groundwater model. A solute concentration source was added in the

An evaluation of the sociodemographic determinants of dental anxiety in patients scheduled for intra-alveolar extraction

Directory of Open Access Journals (Sweden)

Peter E. Egbor

2014-09-01

Full Text Available Background: Studies on anxiety in patients having intra-alveolar extraction as well as the effect of patient's sociodemographic characteristics influencing level of associated anxiety are few in our environment. The aim of this study was to statistically analyze the sociodemographic determinants of dental anxiety in patients scheduled for intra-alveolar extraction. Methods: A cross-sectional study was conducted among 93 consecutive patients attending the outpatient clinic of the Department of Maxillofacial Surgery, University of Benin Teaching Hospital for intra-alveolar extraction in the months of November and December 2013. An interview-based questionnaire, Corah Dental Anxiety Scale Revised (DAS-R, was administered to evaluate levels of dental anxiety. Sociodemographic characteristics of the subjects were recorded. Descriptive statistics and regression models were done with the independent variables (sociodemographic factors and the dependent variable being the DAS-R. A P<0.05 was considered significant. Results: The internal consistency of the scale used as determined by Cronbach alpha was 0.76. Mean DAS score was 8.12±2.58. Dental anxiety and age of subjects showed significant inverse relationship. Females had a higher mean DAS score (8.76 than the males (7.37 (P=0.006. Residence (urban/rural was not statistically significant. Singles reported the highest DAS score (9.41 (P=0.006. The educational level attained was significantly related to dental anxiety (P=0.005. Those with secondary school education had the highest DAS score (9.26. Class V social status had the highest mean anxiety score (P=0.012. Stepwise linear regression showed that the best predictors for dental anxiety were sex (P=0.008 and marital status (P=0.026. Conclusion: This present study demonstrates that sex and marital status are the predictive factors for dental anxiety in the overall management of patients indicated for intra-alveolar extraction.

Intra-rater and inter-rater reliability of a medical record abstraction study on transition of care after childhood cancer.

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Micòl E Gianinazzi

Full Text Available The abstraction of data from medical records is a widespread practice in epidemiological research. However, studies using this means of data collection rarely report reliability. Within the Transition after Childhood Cancer Study (TaCC which is based on a medical record abstraction, we conducted a second independent abstraction of data with the aim to assess a intra-rater reliability of one rater at two time points; b the possible learning effects between these two time points compared to a gold-standard; and c inter-rater reliability.Within the TaCC study we conducted a systematic medical record abstraction in the 9 Swiss clinics with pediatric oncology wards. In a second phase we selected a subsample of medical records in 3 clinics to conduct a second independent abstraction. We then assessed intra-rater reliability at two time points, the learning effect over time (comparing each rater at two time-points with a gold-standard and the inter-rater reliability of a selected number of variables. We calculated percentage agreement and Cohen's kappa.For the assessment of the intra-rater reliability we included 154 records (80 for rater 1; 74 for rater 2. For the inter-rater reliability we could include 70 records. Intra-rater reliability was substantial to excellent (Cohen's kappa 0-6-0.8 with an observed percentage agreement of 75%-95%. In all variables learning effects were observed. Inter-rater reliability was substantial to excellent (Cohen's kappa 0.70-0.83 with high agreement ranging from 86% to 100%.Our study showed that data abstracted from medical records are reliable. Investigating intra-rater and inter-rater reliability can give confidence to draw conclusions from the abstracted data and increase data quality by minimizing systematic errors.

Patient Satisfaction After Femoral Arterial Access Site Closure Using the ExoSeal® Vascular Closure Device Compared to Manual Compression: A Prospective Intra-individual Comparative Study

International Nuclear Information System (INIS)

Pieper, Claus Christian; Thomas, Daniel; Nadal, Jennifer; Willinek, Winfried A.; Schild, Hans Heinz; Meyer, Carsten

2016-01-01

PurposeTo intra-individually compare discomfort levels and patient satisfaction after arterial access closure using the ExoSeal ® vascular closure device (VCD) and manual compression (MC) in a prospective study design.MethodsPatients undergoing two planned interventions from 07/2013 to 09/2014 could participate in the study. Access closure was performed with an ExoSeal ® -VCD in one and MC in the other intervention. Patients were clinically and sonographically examined and were given questionnaires 1 day after intervention [groin- and back-pain during bedrest (100-point visual analog scale; 0: no pain); comfortability of bedrest (10-point Likert scale, 1: comfortable), satisfaction with closure (10-point Likert scale, 1: very satisfied)]. Results were analyzed in a cross-over design.Results48 patients (29 male, median age 62.5 (32–88) years) were included. An ExoSeal ® -VCD was used first in 25 cases. As four of these subsequently refused MC as second intervention, data from 44 patients could be analyzed. All closures were technically successful (successful device deployment) without major complications. Groin- and back-pain after VCD-use/MC was 0 (0–15) vs. 10 (0–80) and 0 (0–75) vs. 25 (0–90), respectively (p < 0.0001). Bedrest after VCD-use was more comfortable than after MC [1 (range 1–7) vs. 6 (2–10); p < 0.0001]. Satisfaction with the closure procedure and with the intervention in general was higher after VCD-use compared to MC [1 (1–3) vs. 5 (2–10) and 1 (1–2) vs. 2 (1–4), respectively; p < 0.0001].ConclusionIntra-individual comparison showed pain levels and discomfort to be significantly lower after ExoSeal ® use compared to MC. VCD closure was associated with higher satisfaction both with the closure itself and with the intervention in general

Individual testosterone decline and future mortality risk in men

DEFF Research Database (Denmark)

Holmboe, Stine Agergaard; Skakkebaek, Niels E.; Juul, Anders

2018-01-01

OBJECTIVE: Male aging is characterized by a decline in testosterone (T) levels with a substantial variability between subjects. However, it is unclear whether differences in age-related changes in T are associated with general health. We investigated associations between mortality and intra...

Locally disordered methylation forms the basis of intra-tumor methylome variation in chronic lymphocytic leukemia

Science.gov (United States)

Landau, Dan A.; Clement, Kendell; Ziller, Michael J.; Boyle, Patrick; Fan, Jean; Gu, Hongcang; Stevenson, Kristen; Sougnez, Carrie; Wang, Lili; Li, Shuqiang; Kotliar, Dylan; Zhang, Wandi; Ghandi, Mahmoud; Garraway, Levi; Fernandes, Stacey M.; Livak, Kenneth J.; Gabriel, Stacey; Gnirke, Andreas; Lander, Eric S.; Brown, Jennifer R.; Neuberg, Donna; Kharchenko, Peter V.; Hacohen, Nir; Getz, Gad; Meissner, Alexander; Wu, Catherine J.

2014-01-01

SUMMARY Intra-tumoral heterogeneity plays a critical role in tumor evolution. To define the contribution of DNA methylation to heterogeneity within tumors, we performed genome-scale bisulfite sequencing of 104 primary chronic lymphocytic leukemias (CLL). Compared to 26 normal B cell samples, CLLs consistently displayed higher intra-sample variability of DNA methylation patterns across the genome, which appears to arise from stochastically disordered methylation in malignant cells. Transcriptome analysis of bulk and single CLL cells revealed that methylation disorder was linked to low-level expression. Disordered methylation was further associated with adverse clinical outcome. We therefore propose that disordered methylation plays a similar role to genetic instability, enhancing the ability of cancer cells to search for superior evolutionary trajectories. PMID:25490447

Individual differences in behavioural plasticities.

Science.gov (United States)

Stamps, Judy A

2016-05-01

Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural

Accounting for inter-annual and seasonal variability in regionalization of hydrologic response in the Great Lakes basin

Science.gov (United States)

Kult, J. M.; Fry, L. M.; Gronewold, A. D.

2012-12-01

Methods for predicting streamflow in areas with limited or nonexistent measures of hydrologic response typically invoke the concept of regionalization, whereby knowledge pertaining to gauged catchments is transferred to ungauged catchments. In this study, we identify watershed physical characteristics acting as primary drivers of hydrologic response throughout the US portion of the Great Lakes basin. Relationships between watershed physical characteristics and hydrologic response are generated from 166 catchments spanning a variety of climate, soil, land cover, and land form regimes through regression tree analysis, leading to a grouping of watersheds exhibiting similar hydrologic response characteristics. These groupings are then used to predict response in ungauged watersheds in an uncertainty framework. Results from this method are assessed alongside one historical regionalization approach which, while simple, has served as a cornerstone of Great Lakes regional hydrologic research for several decades. Our approach expands upon previous research by considering multiple temporal characterizations of hydrologic response. Due to the substantial inter-annual and seasonal variability in hydrologic response observed over the Great Lakes basin, results from the regression tree analysis differ considerably depending on the level of temporal aggregation used to define the response. Specifically, higher levels of temporal aggregation for the response metric (for example, indices derived from long-term means of climate and streamflow observations) lead to improved watershed groupings with lower within-group variance. However, this perceived improvement in model skill occurs at the cost of understated uncertainty when applying the regression to time series simulations or as a basis for model calibration. In such cases, our results indicate that predictions based on long-term characterizations of hydrologic response can produce misleading conclusions when applied at shorter

Light induced intraspecific variability in response to thermal stress in the hard coral Stylophora pistillata

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Arjen Tilstra

2017-10-01

Full Text Available Recent research suggests that prior exposure of several months to elevated irradiance induces enhanced thermal tolerance in scleractinian corals. While this tolerance has been reported at the species level, individual coral colonies may react differently due to individual variability in thermal tolerance. As thermal anomalies are predicted to become common in the upcoming future, intraspecific variation may be key to the survival of coral populations. In order to study light-history based thermal stress responses on individual colonies, we developed a preliminary microcosm experiment where three randomly chosen, aquacultured colonies of the model coral Stylophora pistillata were exposed to two irradiance treatments (200 and 400 μmol photons m−2 s−1 for 31 days, followed by artificially induced heat stress (∼33.4 °C. We found different responses to occur at both the intraspecific and the intracolonial levels, as indicated by either equal, less severe, delayed, and/or even non-necrotic responses of corals previously exposed to the irradiance of 400 compared to 200 μmol photons m−2 s−1. In addition, all individual colonies revealed light-enhanced calcification. Finally, elevated irradiance resulted in a lower chlorophyll a concentration in one colony compared to the control treatment, and the same colony displayed more rapid bleaching compared to the other ones. Taken together, this study highlights the potential importance of intra-individual variability in physiological responses of scleractinian corals and provides recommendations for improving methodological designs for future studies.

Sea level variability in the Arctic Ocean observed by satellite altimetry

OpenAIRE

Prandi, P.; Ablain, M.; Cazenave, A.; Picot, N.

2012-01-01

We investigate sea level variability in the Arctic Ocean from observations. Variability estimates are derived both at the basin scale and on smaller local spatial scales. The periods of the signals studied vary from high frequency (intra-annual) to long term trends. We also investigate the mechanisms responsible for the observed variability. Different data types are used, the main one being a recent reprocessing of satellite altimetry data...

Vascular anatomy of the medial sural artery perforator flap: a new classification system of intra-muscular branching patterns.

Science.gov (United States)

Dusseldorp, Joseph R; Pham, Quy J; Ngo, Quan; Gianoutsos, Mark; Moradi, Pouria

2014-09-01

The medial sural artery perforator (MSAP) flap is a versatile fasciocutaneous flap. The main difficulty encountered when raising the MSAP flap is in obtaining adequate pedicle length during intra-muscular dissection. The objective of this study was to determine the pattern of intra-muscular course of the MSAP flap pedicle. 14 cadaveric specimens were dissected and CT angiograms of 84 legs were examined. The intra-muscular branching pattern and depths of the medial sural artery branches were analyzed. The number of perforators, position of the dominant perforator and both intra-muscular and total pedicle length were also recorded and compared to existing anatomical data. Three types of arterial branching pattern were identified within the medial gastrocnemius, demonstrating one (31%), two (59%) or three or more (10%) main branches. A dominant perforator from the medial sural artery was present in 92% of anatomical specimens (13/14). Vertically, the location of the perforator from the popliteal crease was on average 13 cm (±2 cm). Transversely, the perforator originated 2.5 cm (±1 cm) from the posterior midline. Using CT angiography it was possible in 10 consecutive patients to identify a more superficial intra-muscular branch and determine the leg with the optimal branching pattern type for flap harvest. This study is the first to describe the variability of the intra-muscular arterial anatomy of the medial head of gastrocnemius muscle. Surgeons utilizing the MSAP flap option should be aware of the possible branching pattern types and consequently the differing perforator distribution and depths of intra-muscular branches. Routine use of pre-operative CT angiogram may help determine which leg has the most favorable branching pattern type and intra-muscular course for flap harvest. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

An fMRI Study of Intra-Individual Functional Topography in the Human Cerebellum

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Catherine J. Stoodley

2010-01-01

Full Text Available Neuroimaging studies report cerebellar activation during both motor and non-motor paradigms, and suggest a functional topography within the cerebellum. Sensorimotor tasks activate the anterior lobe, parts of lobule VI, and lobule VIII, whereas higher-level tasks activate lobules VI and VII in the posterior lobe. To determine whether these activation patterns are evident at a single-subject level, we conducted functional magnetic resonance imaging (fMRI during five tasks investigating sensorimotor (finger tapping, language (verb generation, spatial (mental rotation, working memory (N-back, and emotional processing (viewing images from the International Affective Picture System. Finger tapping activated the ipsilateral anterior lobe (lobules IV-V as well as lobules VI and VIII. Activation during verb generation was found in right lobules VII and VIIIA. Mental rotation activated left-lateralized clusters in lobules VII-VIIIA, VI-Crus I, and midline VIIAt. The N-back task showed bilateral activation in right lobules VI-Crus I and left lobules VIIB-VIIIA. Cerebellar activation was evident bilaterally in lobule VI while viewing arousing vs. neutral images. This fMRI study provides the first proof of principle demonstration that there is topographic organization of motor execution vs. cognitive/emotional domains within the cerebellum of a single individual, likely reflecting the anatomical specificity of cerebro-cerebellar circuits underlying different task domains. Inter-subject variability of motor and non-motor topography remains to be determined.

Intra-Diegetic Cameras as Cinematic Actor Assemblages in Found Footage Horror Cinema

DEFF Research Database (Denmark)

Rødje, Kjetil

2017-01-01

that comprises what is commonly known as human actors as well as material entities that play an active part in motion picture images. The use of intra-diegetic cameras in contemporary found footage horror films constitutes a particular case of such cinematic actor assemblages. Through a dynamic relational...... performance, cameras here take on roles as active agents with the potential to affect other elements within the images as well as the films’ audiences. In found footage horror the assemblage mode of operation creates suspense, since the vulnerability of the camera threatens the viewer's access to the depicted...... events. While human characters and individual entities making up the camera assemblage are disposable, the recording is not. Found footage horror crucially hinges upon the survival of the footage. I will further suggest that these films allow filmmakers to experiment with the acting capabilities of intra...

Abnormal inter- and intra-hemispheric integration in male paranoid schizophrenia: a graph-theoretical analysis.

Science.gov (United States)

Chen, Jianhuai; Yao, Zhijian; Qin, Jiaolong; Yan, Rui; Hua, Lingling; Lu, Qing

2015-06-25

The human brain is a complex network of regions that are structurally interconnected by white matter (WM) tracts. Schizophrenia (SZ) can be conceptualized as a disconnection syndrome characterized by widespread disconnections in WM pathways. To assess whether or not anatomical disconnections are associated with disruption of the topological properties of inter- and intra-hemispheric networks in SZ. We acquired the diffusion tensor imaging data from 24 male patients with paranoid SZ during an acute phase of their illness and from 24 healthy age-matched male controls. The brain FA-weighted (fractional anisotropy-weighted) structural networks were constructed and the inter- and intra-hemispheric integration was assessed by estimating the average characteristic path lengths (CPLs) between and within the left and right hemisphere networks. The mean CPLs for all 18 inter-and intra-hemispheric CPLs assessed were longer in the SZ patient group than in the control group, but only some of these differences were significantly different: the CPLs for the overall inter-hemispheric and the left and right intra-hemispheric networks; the CPLs for the interhemisphere subnetworks of the frontal lobes, temporal lobes, and subcortical structures; and the CPL for the intra- frontal subnetwork in the right hemisphere. Among the 24 patients, the CPL of the inter-frontal subnetwork was positively associated with negative symptom severity, but this was the only significant result among 72 assessed correlations, so it may be a statistical artifact. Our findings suggest that the integrity of intra- and inter-hemispheric WM tracts is disrupted in males with paranoid SZ, supporting the brain network disconnection model (i.e., the (')connectivity hypothesis(')) of schizophrenia. Larger studies with less narrowly defined samples of individuals with schizophrenia are needed to confirm these results.