nils-herrmann/clean_scirepeval huggingface dataset:
Comparative study of algorithms for synthetic CT generation from MRI: Consequences for MRI‐guided radiation planning in the pelvic region

Magnetic resonance imaging (MRI)-guided radiation therapy (RT) treatment planning is limited by the fact that the electron density distribution required for dose calculation is not readily provided by MR imaging. We compare a selection of novel synthetic CT generation algorithms recently reported in the literature, including segmentation-based, atlas-based and machine learning techniques, using the same cohort of patients and quantitative evaluation metrics.



Six MRI-guided synthetic CT generation algorithms were evaluated: one segmentation technique into a single tissue class (water-only), four atlas-based techniques, namely, median value of atlas images (ALMedian), atlas-based local weighted voting (ALWV), bone enhanced atlas-based local weighted voting (ALWV-Bone), iterative atlas-based local weighted voting (ALWV-Iter), and a machine learning technique using deep convolution neural network (DCNN).



Organ auto-contouring from MR images was evaluated for bladder, rectum, bones, and body boundary. Overall, DCNN exhibited higher segmentation accuracy resulting in Dice indices (DSC) of 0.93 ± 0.17, 0.90 ± 0.04, and 0.93 ± 0.02 for bladder, rectum, and bones, respectively. On the other hand, ALMedian showed the lowest accuracy with DSC of 0.82 ± 0.20, 0.81 ± 0.08, and 0.88 ± 0.04, respectively. DCNN reached the best performance in terms of accurate derivation of synthetic CT values within each organ, with a mean absolute error within the body contour of 32.7 ± 7.9 HU, followed by the advanced atlas-based methods (ALWV: 40.5 ± 8.2 HU, ALWV-Iter: 42.4 ± 8.1 HU, ALWV-Bone: 44.0 ± 8.9 HU). ALMedian led to the highest error (52.1 ± 11.1 HU). Considering the dosimetric evaluation results, ALWV-Iter, ALWV, DCNN and ALWV-Bone led to similar mean dose estimation within each organ at risk and target volume with less than 1% dose discrepancy. However, the two-dimensional gamma analysis demonstrated higher pass rates for ALWV-Bone, DCNN, ALMedian and ALWV-Iter at 1%/1 mm criterion with 94.99 ± 5.15%, 94.59 ± 5.65%, 93.68 ± 5.53% and 93.10 ± 5.99% success, respectively, while ALWV and water-only resulted in 86.91 ± 13.50% and 80.77 ± 12.10%, respectively.



Overall, machine learning and advanced atlas-based methods exhibited promising performance by achieving reliable organ segmentation and synthetic CT generation. DCNN appears to have slightly better performance by achieving accurate automated organ segmentation and relatively small dosimetric errors (followed closely by advanced atlas-based methods, which in some cases achieved similar performance). However, the DCNN approach showed higher vulnerability to anatomical variation, where a greater number of outliers was observed with this method. Considering the dosimetric results obtained from the evaluated methods, the challenge of electron density estimation from MR images can be resolved with a clinically tolerable error.

Field of study: Medicine, Physics
Recent progress in pion photo- and electroproduction analysis

Pion photo- and electroproduction has been studied at threshold and in the resonance region below W=2GeV. At threshold pi^0 production can be very well explained within a dynamical model derived from an effective chiral Lagrangian. The final state interaction is nearly saturated by single charge exchange rescattering. In the resonance region new electroproduction data at Q^2=1GeV^2 has been analyzed with MAID and longitudinal and transverse photon helicity amplitudes have been determined for different resonances. A detailed study of the E/M and S/M ratios of the N->Delta transition shows a zero crossing of REM near Q^2=4GeV^2, whereas the RSM becomes increasingly negative at large Q^2.

Field of study: Physics
Implicit Gender Stereotypes and Essentialist Beliefs Predict Preservice Teachers’ Tracking Recommendations

This study investigated the extent to which differences in implicit and explicit math–language gender stereotypes, and essentialist beliefs among preservice teachers affect tracking recommendations for math/science- versus language-oriented secondary schools. Consistent with expectations, the results suggest that student's gender influences preservice teachers’ school career recommendations: Boys are more likely to be recommended for a math/science-oriented secondary school, whereas girls are more likely recommended for a language-oriented school. Both implicit math–language gender stereotypes and beliefs in genetic determinism (reflecting essentialist beliefs) predicted the stereotypicality of school career recommendations, whereas explicit measures did not. The results suggest that more closely investigating factors contributing to stereotypical behavior in teachers might help to minimize biased actions and decisions in the educational context.

Field of study: Education
Non-linear Bending, Buckling and Failure of Elastic Thin Circular Plates Under Combined Thermal and Force Loading

The governing equations of non-linear dynamic response of an axisymmetric elastic thin circular plate subjected to an arbitrarily transverse force and a thermal energy deposit are formulated.Deformation features of thin circular plates and the factors that affect failure are discussed by a quasi-static analysis.It is shown that thermal buckling is one of the major failure modes of thin circular plates in the case of short duration thermal energy deposit. Thermal buckling always occurs before reverse bulging or reverse plugging.Similar to the increase of the transverse load,the increase of the power level of thermal energy deposit will accelerate the thermal buckling.The temperature dependence of material properties and the time-space distribution of thermal energy deposit both significantl

Field of study: Physics
Reduction in Bladder Volume Alters Expression of Hypocretin/Orexin Receptors in Brain Stem in Rats: a Correlation With Sleep Architecture

Our recent study revealed that enuretic children have more light sleep associated with frequent cortical arousals. The neurons of the lateral hypothalamic and perifornical areas that express Hypocretin/Orexin(Hcrt/Orx) have been implicated in control of sleep- wake cycle and CNS arousal mechanisms. We therefore propose to use an animal model to evaluate brain functional changes in response to bladder dysfunction.  Twenty four adult male New Zealand Wistar rats were used. Animals underwent either surgical reduction of bladder volume (RBV, n = 12) or SHAM operation (n = 12). Animals were kept in metabolic cages for noninvasive monitoring of voiding patterns. Radiotelemeters were implanted in both groups after 4 weeks of recovery and electroencephalogram was recorded via readiotelemetric probes. On completion, animals were anesthetized and brain samples harvested. Serial cryostat sections of brain were obtained throughout the hypothalamus and the sections were immunostained for Hcrt -1.  Voided volume significantly reduced and voiding frequency increased in RBV group. Our results demonstrated impaired sleep architecture in animals with reduced bladder volume. Light non-rapid eye movement sleep occurred more and deep and rapid eye movement sleep occurred significantly less RBV group (59.2% vs 35.6%, p   An alteration in sleep architecture occurred in response to surgical reduction of bladder volume in rats. Enhancement of arousal accompanied by marked reduction in paradoxical sleep and deep slow wave sleep correlated with significant increase in Hcrt/Orx cells in RBV group, suggesting the existence of a dialogue of dysfunctional bladder and CNS.

Field of study: Medicine
Going beyond Free Viewpoint: Creating Animatable Volumetric Video of Human Performances

In this paper, we present an end-to-end pipeline for the creation of high-quality animatable volumetric video content of human performances. Going beyond the application of free-viewpoint volumetric video, we allow re-animation and alteration of an actor's performance through (i) the enrichment of the captured data with semantics and animation properties and (ii) applying hybrid geometry- and video-based animation methods that allow a direct animation of the high-quality data itself instead of creating an animatable model that resembles the captured data. Semantic enrichment and geometric animation ability are achieved by establishing temporal consistency in the 3D data, followed by an automatic rigging of each frame using a parametric shape-adaptive full human body model. Our hybrid geometry- and video-based animation approaches combine the flexibility of classical CG animation with the realism of real captured data. For pose editing, we exploit the captured data as much as possible and kinematically deform the captured frames to fit a desired pose. Further, we treat the face differently from the body in a hybrid geometry- and video-based animation approach where coarse movements and poses are modeled in the geometry only, while very fine and subtle details in the face, often lacking in purely geometric methods, are captured in video-based textures. These are processed to be interactively combined to form new facial expressions. On top of that, we learn the appearance of regions that are challenging to synthesize, such as the teeth or the eyes, and fill in missing regions realistically in an autoencoder-based approach. This paper covers the full pipeline from capturing and producing high-quality video content, over the enrichment with semantics and deformation properties for re-animation and processing of the data for the final hybrid animation.

Field of study: Computer science
PURIFYING WASTE GAS CONTAINING LOW CONCENTRATION TOLUENE IN TRICKLING BIOFILTER WITH CERAMIC SPHERES

The Purification experiments of waste gas containing low concentration toluene were made in trickling biofilter with ceramic spheres.The effects of liquid flow rate, gas flow rate, pH of circulation liquid, and toluene concentration in inlet gas on the purification efficiency of trickling biofilter were investigated.The pressure drop of the trickling biofilter was also measured during experiments. Increasing liquid flow rate and gas flow rate resulted in the decrease of purification efficiency of trickling biofilter.The highest purification efficiency of trickling biofilter was found at the circulation liquid pH of 7.The porosity of the packing material at the inlet of gas was higher than that at the outlet of gas in biofilter after continuous operation in 50 days. The decrease in the porosity of packing material caused a great increase in the pressure drop of the biofilter.

Field of study: Chemistry, Environmental science
Imposing structure on Smith-form decompositions of rational resampling matrices

Imposing structure on the Smith form of an (integer) periodicity matrix N=U/spl Lambda/V leads to efficient multidimensional (m-D) DFT implementations (Guessoum, 1984). For nonsingular integer and rational matrices, the authors introduce algorithms to generate U (or V) matrices with minimum norm and /spl Lambda/ matrices whose diagonal elements exhibit minimum variance. Such structure simplifies nonuniform m-D filter-bank design (Gardos et al. 1992).

Field of study: Engineering
Women's Empowerment and Economic Development

Women's empowerment and economic development are closely related: in one direction, development alone can play a major role in driving down inequality between men and women; in the other direction, empowering women may benefit development. Does this imply that pushing just one of these two levers would set a virtuous circle in motion? This paper reviews the literature on both sides of the empowerment-development nexus, and argues that the inter-relationships are probably too weak to be self-sustaining, and that continuous policy commitment to equality for its own sake may be needed to bring about equality between men and women.

Field of study: Sociology
A computational method for solving periodic boundary value problems for integro-differential equations of Fredholm-Volterra type

In this paper, the numerical solution of periodic Fredholm–Volterra integro–differential equations of first-order is discussed in a reproducing kernel Hilbert space. A reproducing kernel Hilbert space is constructed, in which the periodic condition of the problem is satisfied. The exact solution u x is represented in the form of series in the space W 2 2 . In the mean time, the n-term approximate solution u n x is obtained and is proved to converge to the exact solution u x . Furthermore, we present an iterative method for obtaining the solution in the space W 2 2 . Some examples are displayed to demonstrate the validity and applicability of the proposed method. The numerical result indicates that the proposed method is straightforward to implement, efficient, and accurate for solving linear and nonlinear equations.

Field of study: Mathematics
Absence of anticipatory contrast in rats trained on multiple schedules.

Rats were trained on three- and four-component multiple schedules in which two of the components were correlated with identical reinforcement schedules that remained unchanged throughout training. These target components differed in terms of whether their respective following schedules were either higher or lower in value. Unlike corresponding experiments previously reported with pigeons, higher response rates occurred in the target component followed by a higher valued schedule than in the target component followed by the lower valued schedule. Overall contrast effects occurred independently of these sequential effects, but were inconsistent across subjects. The results suggest that the effects of a following schedule of reinforcement are opposite for pigeons and rats, and that one reason previous studies have often failed to show contrast effects with rats is that the effects of the following schedule in rats are in competition with contrast dynamics.

Field of study: Biology, Psychology
Tomographic retrievals of ozone with the OMPS Limb Profiler: algorithm description and preliminary results

Measurements of limb-scattered sunlight from the Ozone Mapping and Profiler Suite Limb Profiler (OMPS-LP) can be used to
obtain vertical profiles of ozone in the stratosphere. In this paper we describe a two-dimensional, or tomographic,
retrieval algorithm for OMPS-LP where variations are retrieved simultaneously in altitude and the along-orbital-track
dimension. The algorithm has been applied to measurements from the center slit for the full OMPS-LP mission to create the
publicly available University of Saskatchewan (USask) OMPS-LP 2D v1.0.2 dataset. Tropical ozone anomalies are compared with measurements from the
Microwave Limb Sounder (MLS), where differences are less than 5 % of the mean ozone value for the majority of the
stratosphere. Examples of near-coincident measurements with MLS are also shown, and agreement at the 5 % level is
observed for the majority of the stratosphere. Both simulated retrievals and coincident comparisons with MLS are shown at
the edge of the polar vortex, comparing the results to a traditional one-dimensional retrieval. The one-dimensional
retrieval is shown to consistently overestimate the amount of ozone in areas of large horizontal gradients relative to
both MLS and the two-dimensional retrieval.

Field of study: Environmental science
On the Control and Prevention of Risks in Labor Dispatching Employment Units——In the Perspective of Labor Law

With reference to the employment practice of labor dispatching and in accordance with regulations of labor law,the paper proposes some constructive suggestions to controlling and preventing current risks of labor dispatching employment units,mainly on how to select the labor dispatching agencies,how to standardize the labor-dispatching protocol,how to set the reasonable labor dispatching positions and how to establish a reasonable wage system.

Field of study: Agricultural and Food sciences
Children, Class, and the Search for Security: Writing the Future in 1930s Britain.

This article is based on 269 essays written in 1937 by Middlesbrough schoolboys aged 12-16 years on the topic 'When I leave school', which were collected by the social research organization Mass Observation. The essays provide a counterpoint to social scientific surveys of ordinary people and allow us to work with the boys' own understandings of the world they inhabited. They offer an alternative lens on a period which, at least in relation to the industrial areas of Britain, is often characterized by poverty and unemployment. This representation is largely absent from the children's essays: instead, an overwhelming sense of possibility characterizes their writing, from their wildest fantasies to their most concrete plans. Most dreamt of lives that would be long, fulfilling, domesticated, and happy. This is not to say that they were oblivious to the world around them; indeed an emphasis on security and planning suggested an implicit awareness of material context. Nonetheless these boys expressed a marked determination that their lives would be better than those of their parents. As such, they embodied the educational and occupational aspirations that are more often seen as characteristic of post-war Britain. Their essays illustrate emergent and widely held expectations of social mobility and dreams of cradle-to-grave security in the years before the Second World War, articulated-as they were being lived-by a generation which would go on to elect the 1945 Labour government.

Field of study: History
How Sandcastles Fall

Exxon Research and Engineering, Route 22 East, Annandale, N.J. 08801(February 1, 2008)Capillary forces signiﬁcantly aﬀect the stability of sandpiles. We analyze the stability of sandpileswith such forces, and ﬁnd that the critical angle is unchanged in the limit of an inﬁnitely largesystem; however, this angle is increased for ﬁnite-sized systems. The failure occurs in the bulk ofthe sandpile rather than at the surface. This is related to a standard result in soil mechanics. Theincrease in the critical angle is determined by the surface roughness of the particles, and exhibitsthree regimes as a function of the added-ﬂuid volume. Our theory is in qualitative agreement withthe recent experimental results of Hornbaker et al., although not with the interpretation they makeof these results.81.05.Rm, 68.45.Gd, 91.50.Jc

Field of study: Physics
Production and Characterization of (004) Oriented Single Anatase TiO2 Films

Highly (004) oriented anatase TiO2 films have been successfully obtained by an inexpensive ultrasonic spray pyrolysis technique at low substrate temperatures and without additional annealing. X-ray diffraction analysis, ultraviolet–visible spectroscopy and field emission scanning electron microscopy were used to analyze the structural, optical and surface properties of the films. By using the less reported TiCl4 solution, the optical band gap values falling into the visible region (between 2.70 eV and 2.92 eV) have been obtained for all films. Spectroscopic ellipsometry technique has been used to determine the dispersive refractive index and extinction coefficient of TiO2 films. Possible electrical conduction mechanisms in TiO2 films have been examined using temperature dependent conductivity measurements in the temperature range of 78–300 K. At room temperature, electrical resistivity values of TiO2 films change between 1.68 × 104 Ω cm and 5.88 × 104 Ω cm. Considering the analyzed parameters with respect to substrate temperature, this work refers to the properties of anatase TiO2 films that are strongly correlated to the growth direction, namely (004). As a result, (004) oriented anatase TiO2 films with appropriate optical band gap values are promising materials for technological applications, especially for photocatalysts.

Field of study: Materials science
System ESD robustness by co-design of on-chip and on-board protection measures

System-level ESD robustness is a crucial feature for any electronic system. However, a consistent design methodology including IC-level protection, on-board protection and physical design of the module is still missing. The idea of a simple correlation between IC-level and system-level ESD robustness levels is misleading. A thorough characterization of the high current behaviour of IO circuit and on-board protection elements provides the necessary data for a simulation based co-design of on-chip and on-board protection measures. The constraints for characterization and modelling are discussed and the various protection measures for improved system-level ESD robustness are presented. Applying this methodology allows the development of a cost optimized system-level ESD protection throughout the stages of a system design.

Field of study: Engineering
Role of ethylene in alleviation of cadmium-induced photosynthetic capacity inhibition by sulphur in mustard.

Sulphur (S) assimilation leads to the formation of glutathione (GSH) and alleviation of cadmium (Cd) stress. GSH is synthesized from its immediate metabolite cysteine, which also serves as a metabolite for ethylene formation through S-adenosyl methionine. To assess the role of ethylene in S-induced alleviation of Cd stress on photosynthesis, the effects of S or ethephon (ethylene source) on GSH and ethylene were examined in mustard (Brassica juncea L. cv. Varuna). Sufficient-S at 100 mg S kg(-1) soil alleviated Cd-induced photosynthetic inhibition more than excess-S (200 mg S kg(-1) soil) via ethylene by increased GSH. Under Cd stress, plants were less sensitive to ethylene, despite high ethylene evolution, and showed photosynthetic inhibition. Ethylene sensitivity of plants increased with ethephon or sufficient-S, triggering the induction of an antioxidant system, and leading to increased photosynthesis even under Cd stress. The effects of ethephon and S under Cd stress were similar. The effects of S were reversed by ethylene biosynthesis inhibitor, aminoethoxyvinylglycine (AVG), suggesting that ethylene plays an important role in S-induced alleviation of Cd stress on photosynthesis.

Field of study: Environmental science
Passivation and packaging of positive bevelled edge termination and related electrical stability

Low cost high power diodes usually use a MESA structure as an edge termination, filled with resin or glass. This paper provides an extensive analysis of the power diodes voltage capability as a function of the main geometrical and technological parameters. The effect of the fixed charge density inherent to the MESA groove filling material is also considered. Technological and electrical 2D simulations have been carried out to monitor the dependence on each parameter and to determine the location of the breakdown point. Fagor commercial MESA power diodes have been used to corroborate experimentally the optimisation of the voltage capability. Finally, a new axial package design which significantly enhances the device reliability has been developed, successfully tested and transferred into the Fagor production line.

Field of study: Engineering