bluuebunny/crossref_metadata_2025_split huggingface dataset:
Circulating levels of pegvisomant and endogenous growth hormone during prolonged pegvisomant therapy in patients with acromegaly
Authors: Madsen Michael , Fisker Sanne , Feldt‐Rasmussen Ulla , Andreassen Mikkel , Kristensen Lars Østergaard , Ørskov Hans , Jørgensen Jens Otto L. 
Published: May 2013

SummaryObjectiveTo investigate whether pegvisomant treatment in acromegaly induces gradual elevations in endogenous serum growth hormone (GH) levels and whether serum pegvisomant levels predict the therapeutic outcome.Patients and MethodsSeventeen patients (6 women), mean age 46·3 years (range: 23·2–76·2), were studied. For each patient, four hospital visits were identified including ‘active disease’ (no treatment) and last follow‐up. At each visit, 12 blood samples were drawn during 3 h including an oral glucose tolerance test (OGTT). Eight patients received a somatostatin analogue in addition to pegvisomant on the last visit.ResultsMedian (range) pegvisomant doses (mg/day) were 10 (10–10), 15 (10–15) and 15 (10–15) at visits 2, 3 and 4, respectively, and the mean duration of pegvisomant treatment was 17·5 ± 3·2 (SEM) months. Serum IGF‐I changed significantly during the treatment period with the highest level at baseline and lowest levels at visits 3 and 4. GH levels increased in a dose‐dependent manner during pegvisomant treatment and decreased at visit 4. Changes in IGF‐I levels correlated negatively with changes in serum pegvisomant levels between visits. Serum pegvisomant at each visit correlated with baseline growth hormone levels, whereas no associations between serum pegvisomant and either dose, gender, age or body weight were found.Conclusions(1) Serum GH levels increased initially, but remained stable during prolonged pegvisomant treatment in patients with acromegaly, (2) serum pegvisomant levels predicted the reduction in serum IGF‐I during treatment and (3) the interindividual variation in serum pegvisomant levels seems not predicted by either age, gender or body composition.
Preventive therapy and resilience promotion: an evaluation of social work led skills development group work
Authors: Sheppard Michael , Clibbens John 
Published: May 2013

AbstractConcerns have been expressed for some time about a decline in emphasis on therapeutic work in social work, notably articulated in the Munro Review. Further concerns have been expressed in child care that social workers have increasingly had to focus on child protection work rather than earlier stages of prevention. However, there remain opportunities for social workers through the development of new programmes. One development has been that of Behaviour and Education Support Teams: multi‐professional teams, containing as a key element social workers, and encouraging novel practices designed to help emotional stability and improved behaviour and education performance. This study reports on an evaluation of a social worker delivered school‐based social skills programme, which can contribute to the important area of resilience. This showed significant and sustained improvements in pro‐social behaviour and friendships. The implications of this for the therapeutic potential and professional role of social work are discussed.
Circular Arc Snakes and Kinematic Surface Generation
Authors: Bartoň M. , Shi L. , Kilian M. , Wallner J. , Pottmann H. 
Published: May 2013

AbstractWe discuss the theory, discretization, and numerics of curves which are evolving such that part of their shape, or at least their curvature as a function of arc length, remains unchanged. The discretization of a curve as a smooth sequence of circular arcs is well suited for such purposes, and allows us to reduce evolution of curves to the evolution of a control point collection in a certain finite‐dimensional shape space. We approach this evolution by a 2‐step process: linearized evolution via optimized velocity fields, followed by optimization in order to exactly fulfill all geometric side conditions. We give applications to freeform architecture, including “rationalization” of a surface by congruent arcs, form finding and, most interestingly, non‐static architecture.
Accurate Binary Image Selection from Inaccurate User Input
Authors: Subr Kartic , Paris Sylvain , Soler Cyril , Kautz Jan 
Published: May 2013

AbstractSelections are central to image editing, e.g., they are the starting point of common operations such as copy‐pasting and local edits. Creating them by hand is particularly tedious and scribble‐based techniques have been introduced to assist the process. By interpolating a few strokes specified by users, these methods generate precise selections. However, most of the algorithms assume a 100% accurate input, and even small inaccuracies in the scribbles often degrade the selection quality, which imposes an additional burden on users. In this paper, we propose a selection technique tolerant to input inaccuracies. We use a dense conditional random field (CRF) to robustly infer a selection from possibly inaccurate input. Further, we show that patch‐based pixel similarity functions yield more precise selection than simple point‐wise metrics. However, efficiently solving a dense CRF is only possible in low‐dimensional Euclidean spaces, and the metrics that we use are high‐dimensional and often non‐Euclidean. We address this challenge by embedding pixels in a low‐dimensional Euclidean space with a metric that approximates the desired similarity function. The results show that our approach performs better than previous techniques and that two options are sufficient to cover a variety of images depending on whether the objects are textured.
Path Space Regularization for Holistic and Robust Light Transport
Authors: Kaplanyan Anton S. , Dachsbacher Carsten 
Published: May 2013

AbstractWe propose a simple yet powerful regularization framework for robust light transport simulation. It builds on top of existing unbiased methods and resorts to a consistent estimation using regularization only for paths which cannot be sampled in an unbiased way. To introduce as little bias as possible, we selectively regularize individual interactions along paths, and also derive the regularization consistency conditions. Our approach is compatible with the majority of unbiased methods, e.g. (bidirectional) path tracing and Metropolis light transport (MLT), and only a simple modification is required to adapt existing renderers. We compare to recent unbiased and consistent methods and show examples of scenes with difficult light paths, where regularization is required to account for all illumination features. When coupled with MLT we are able to sample all phenomena, like recent consistent methods, while achieving superior convergence.
Locally Adaptive Products for All‐Frequency Relighting
Authors: Inger Yaron , Farbman Zeev , Lischinski Dani 
Published: May 2013

AbstractTriple product integrals evaluate the shading at a point by factoring the reflection equation into incident illumination, visibility, and BRDF. By densely sampling the space of incident directions, this approach is capable of highly accurate rendering scenes lit by high‐frequency environment lighting, containing complex materials and featuring intricate shadows. Efficient evaluation of triple product integrals using Haar wavelets enables near‐interactive rendering of such scenes, while dynamically changing the lighting and the view. Although faster methods have been proposed in the recent real‐time rendering literature, the approximations employed in these methods typically limit them to lower frequency phenomena.In this paper, we present a new approach for high‐frequency scene relighting within the triple product framework. Our approach breaks the computation to smaller solid angles (blocks) over most of which the triple product degenerates to a dot product. We introduce a lossless, yet compact, differential representation of the visibility function over each block, and sample the BRDF on the fly, eliminating the need to store multiple rotated copies of each BRDF. By combining these ideas, we are able to achieve true interactive performance even when running on a CPU, while supporting high frequency effects in scenes with high vertex counts.
Global Selection of Stream Surfaces
Authors: Esturo Janick Martinez , Schulze Maik , Rössl Christian , Theisel Holger 
Published: May 2013

AbstractStream surfaces are well‐known and widely‐used structures for 3D flow visualization. A single surface can be sufficient to represent important global flow characteristics. Unfortunately, due to the huge space of possible stream surfaces, finding the globally most representative stream surface turns out to be a hard task that is usually performed by time‐consuming manual trial and error exploration using slight modifications of seed geometries. To assist users we propose a new stream surface selection method that acts as an automatic preprocessing step before data analysis. We measure stream surface relevance by a novel surface‐based quality measure that prefers surfaces where the flow is aligned with principal curvature directions. The problem of seed structure selection can then be reduced to the computation of simple minimal paths in a weighted graph spanning the domain. We apply a simulated annealing‐based optimization method to find smooth seed curves of globally near‐optimal stream surfaces. We illustrate the effectiveness of our method on a series of synthetic and real‐world data sets.
Mesh‐Free Discrete Laplace–Beltrami Operator
Authors: Petronetto F. , Paiva A. , Helou E. S. , Stewart D. E. , Nonato L. G. 
Published: May 2013

AbstractIn this work we propose a new discretization method for the Laplace–Beltrami operator defined on point‐based surfaces. In contrast to the existing point‐based discretization techniques, our approach does not rely on any triangle mesh structure, turning out truly mesh‐free. Based on a combination of Smoothed Particle Hydrodynamics and an optimization procedure to estimate area elements, our discretization method results in accurate solutions while still being robust when facing abrupt changes in the density of points. Moreover, the proposed scheme results in numerically stable discrete operators. The effectiveness of the proposed technique is brought to bear in many practical applications. In particular, we use the eigenstructure of the discrete operator for filtering and shape segmentation. Point‐based surface deformation is another application that can be easily carried out from the proposed discretization method.
Graft macrosteatosis and time of T‐tube removal as risk factors for biliary strictures after liver transplantation
Authors: Lattanzi Barbara , Lai Quirino , Guglielmo Nicola , Giannelli Valerio , Merli Manuela , Giusto Michela , Melandro Fabio , Ginanni Corradini Stefano , Mennini Gianluca , Berloco Pasquale Bartolomeo , Rossi Massimo 
Published: May 2013

AbstractBiliary strictures (BS) remain a significant problem following liver transplantation (LT), representing an important cause of morbidity. The purpose of this follow‐up study was to evaluate the incidence and risk factors associated with BS after LT. From 2001 to 2009, 244 consecutive patients underwent LT at our center. Multiple donor and recipient variables were collected for each patient. Exclusion criteria were hepaticojejunostomy, living‐donor LT, and follow‐up less than three months. We reviewed 177 patients, all of whom underwent an end‐to‐end choledochocholedochostomy and T‐tube placement. BS occurred in 23% of patients. Multivariate analysis revealed that graft macrovesicular steatosis >25% (p = 0.05, OR 3.38) and time of T‐tube removal less than six months (p = 0.02, OR 2.53) were independent risk factors for BS. Biliary strictures did not affect patient and graft survival. Donor macrovesicular steatosis represents a risk factor for BS, contributing to liver damage through a reduction in hepatic blood flow. Time of T‐tube removal seems to play a role in the development of BS, although it is unclear whether it represents the cause or the consequence of the development of BS.
Species distribution modelling for the people: unclassified landsat TM imagery predicts bird occurrence at fine resolutions
Authors: Shirley S. M. , Yang Z. , Hutchinson R. A. , Alexander J. D. , McGarigal K. , Betts M. G. 
Published: May 2013

AbstractAimAssessing the influence of land cover in species distribution modelling is limited by the availability of fine‐resolution land‐cover data appropriate for most species responses. Remote‐sensing technology offers great potential for predicting species distributions at large scales, but the cost and required expertise are prohibitive for many applications. We test the usefulness of freely available raw remote‐sensing reflectance data in predicting species distributions of 40 commonly occurring bird species in western Oregon.LocationCentral Coast Range, Cascade and Klamath Mountains Oregon, USA.MethodsInformation on bird observations was collected from 4598 fixed‐radius point counts. Reflectance data were obtained using 30‐m resolution Landsat imagery summarized at scales of 150, 500, 1000 and 2000 m. We used boosted regression tree (BRT) models to analyse relationships between distributions of birds and reflectance values and evaluated prediction performance of the models using area under the receiver operating characteristic curve (AUC) values.ResultsPrediction success of models using all reflectance values was high (mean AUC = 0.79 ± 0.10 SD). Further, model performance using individual reflectance bands exceeded those that used only Normalized Difference Vegetation Index (NDVI). The relative influence of band 4 predictors was highest, indicating the importance of variables associated with vegetation biomass and photosynthetic activity. Across spatial scales, the average influence of predictors at the 2000 m scale was greatest.Main ConclusionsWe demonstrate that unclassified remote‐sensing imagery can be used to produce species distribution models with high prediction success. Our study is the first to identify general patterns in the usefulness of spectral reflectances for species distribution modelling of multiple species. We conclude that raw Landsat Thematic Mapper data will be particularly useful in species distribution models when high‐resolution predictions are required, including habitat change detection studies, identification of fine‐scale biodiversity hotspots and reserve design.
Thickness and fit of mouthguards according to heating methods
Authors: Mizuhashi Fumi , Koide Kaoru , Takahashi Mutsumi 
Published: May 2013

AbstractThe purpose of this study was to examine the difference in the thickness and fit of mouthguards made by four different heating methods of the mouthguard sheet material. A Sports Mouthguard® of 3.8‐mm thickness was used in this study. Four heating methods were performed. In one method, the sheet was heated only one side. In the other methods, one side of the sheet was heated first until the center of the sheet was displaced by 0.5 cm, 1.0 cm, and 1.5 cm from the baseline, and then turned upside down and heated. The sheets were adapted using a vacuum former when the heated sheets hung 1.5 cm from the baseline. We measured the thickness and fit of the mouthguard at the areas of the central incisor and first molar. The difference in thickness at the central incisor and first molar regions was analyzed by two‐way anova. The difference in fit with different heating methods was analyzed by one‐way anova. The results showed that the thickness of the mouthguard differed in the central incisor and first molar areas (P < 0.01 or P < 0.05), but not with the heating methods. The fit of the mouthguard at the central incisor and first molar areas was significantly different among the heating methods (P < 0.01 and P < 0.05). These results suggested that the fit of the mouthguard was superior when the heated surface of the sheet contacted the surface of the working model. This finding may help to fabricate accurate mouthguards.
Links between riparian landcover, instream environment and fish assemblages in headwater streams of south‐eastern Brazil
Authors: Cruz Bruna B. , Miranda Leandro E. , Cetra Mauricio 
Published: May 2013

AbstractWe hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River Basin, south‐eastern Brazil. We focused on seven environmental factors each represented by one or multiple environmental variables and seven fish functional traits each represented by two or more classes. Multivariate direct gradient analyses suggested that riparian zone landcover can be considered a higher level causal factor in a network of relations that control instream characteristics and fish assemblages. Our results provide a framework for a hierarchical conceptual model that identifies singular and collective influences of variables from different scales on each other and ultimately on different aspects related to stream fish functional composition. This conceptual model is focused on the relationships between riparian landcover and instream variables as causal factors on the organisation of stream fish assemblages. Our results can also be viewed as a model for headwater stream management in that landcover can be manipulated to influence factors such as bank composition, substrates and water quality, whereas fish assemblage composition can be used as indicators to monitor the success of such efforts.
A new method for continuously measuring the δ13C of soil CO2 concentrations at different depths by laser spectrometry
Authors: Parent F. , Plain C. , Epron D. , Maier M. , Longdoz B. 
Published: May 2013

SummarySoil carbon dioxide (CO2) efflux is an important component of the carbon (C) cycle but the biological and physical processes involved in soil CO2 production and transport are not fully understood. To improve our knowledge, we present a new approach to measure simultaneously soil CO2 concentrations and efflux, and their respective isotopic signatures (δ13C‐CO2). To quantify soil air 13CO2 and 12CO2 concentrations, we adapted a method based on CO2 diffusion from soil pores into tubes with a highly gas‐permeable membrane wall. These tubes were placed horizontally at different depths in the soil. Air was sampled automatically from the tubes and injected through a diluting system into a tuneable diode laser absorption spectrometer. The CO2 and δ13C‐CO2 vertical profiles were thus obtained at hourly intervals. Our tests demonstrated the absence of fractionation in the membrane tubes for δ13C‐CO2. Subsequently, we set up field experiments for two forest soils, which showed that natural soil CO2 concentrations and δ13C‐CO2 were not affected significantly by the measurement system. While δ13C‐CO2 in air‐filled pores below 5 cm was constant over 3 days, we observed large diurnal variations in δ13C‐CO2 efflux. However, the average difference between the two measurements was close to −4.4‰, which supports steady‐state diffusion over this 3‐day period. This new method seems to be a very effective way to measure the δ13C‐CO2 profile of the soil atmosphere, and demonstrates that the fractionation that occurs during diffusion is the main transport process that affects the δ13C‐CO2 of the soil CO2 efflux on a daily timescale while advection may account for within‐day variations.
Speaker verification using heterogeneous neural network architecture with linear correlation speech activity detection
Authors: Tashan Tariq , Allen Tony , Nolle Lars 
Published: May 2013

AbstractThis paper presents a multi‐level speaker verification system that uses 64 discrete Fourier transform spectrum components as input feature vectors. A speech activity detection technique is used as a pre‐processing stage to identify vowel phoneme boundaries within a speech sample. A modified self‐organising map (SOM) is then used to filter the speech data by using cluster information extracted from three vowels for a claimed speaker. This SOM filtering stage also provides coarse speaker verification. Finally, a second speaker verification level of three multi‐layer perceptron networks classifies the filtered frames provided by the SOMs. These multi‐layer perceptrons work as fine‐grained vowel‐based speaker verifiers. The proposed verification algorithm shows a performance of 94.54% when evaluated using 50 speakers from the Centre for Spoken Language Understanding speaker verification database. In addition, it is shown that the novel discrete Fourier transform spectrum‐based linear correlation pre‐processing technique, presented here, provides the system with greater robustness against changes in speech volume levels when compared with an equivalent energy frame analysis.
The effect of throat underflushing on the fatigue strength of fillet weldments
Authors: Livieri P. , Tovo R. 
Published: May 2013

ABSTRACTThe paper deals with the effect of the weld bead geometry on the fatigue strength of a joint, mainly focusing on geometry change due to post‐weld grinding. The weld toe burr grinding usually has a positive effect on the fatigue strength; however, excessive material removal at the weld throat can decrease its strength. This effect was experimentally evaluated and compared with proper numerical estimations. By means of the numerical evaluations of the effective stress, obtained by the implicit gradient method, the estimation of the geometric component of the grinding process is possible. With this procedure, it is possible to analyse a real joint, geometrically modelled by laser scanner acquisition, and also to assess the excessive net section reduction in a grinding operation.
Systematic variation in the logarithmic ranges in abundance of freshwater phytoplankton populations
Authors: Talling Jack F. 
Published: May 2013

Summary

The logarithmic scaling of species abundance in phytoplankton populations enables the relative ranges of species between periodic (e.g. annual) upper and lower limits to be defined and compared. Examples are discussed mainly from published information on four lakes, two tropical (lakes George and Victoria) and two high‐latitude temperate (Windermere and Esthwaite Water), differing in seasonality and predominant environmental factors.

Although wide logarithmic ranges (>3 orders, log10 units) do exist in the tropical lakes, there are many examples of narrow ranges (<1.5 orders). In Lake Victoria, the latter are characteristic of species with low maximum abundance measured as biomass that do not appreciably deplete the medium (e.g. of nutrients, light) in a density‐dependent manner, but are indirectly regulated by resource depletion caused by more abundant species and by physical mixing, the predominant environmental seasonality.

In the seasonally equable tropical Lake George, narrow ranges in numerical abundance are predominant. Some are favoured by recruitment from a considerable past accumulation of viable biomass on the sediment.

Annual ranges of under one order are rare in Windermere and Esthwaite Water, and probably in most other temperate lakes, although this value is approached by a few ‘opportunistic’ species (e.g. some cryptomonads) of wide environmental tolerance and some species (e.g. Planktothrix agardhii) of enriched shallow lakes. There is little information for species of very low abundance.

Examples are given of logarithmic plots of a measure of total phytoplankton biomass with time. Annual ranges are markedly less than those of the major individual component species, indicating species replacement.