nils-herrmann/clean_scirepeval huggingface dataset:
Mechanical activation effects on crystal structure and chemical reaction activity of maize starch

Maize starch was mechanically activated by a stirring-type ball mill.The effects of mechanical activation on crystal structure,thermal properties,granule shape and particle size of maize starch were examined by means of X-ray diffraction,differential scanning calorimetry,scanning electron microscope and particle size analyzer.Moreover,mechanically activated maize starch(MAMS)with different activation times was acetylated with acetic anhydride and graft-copolymerized with acrylamide under the same experimental conditions.The mechanical activation effects on chemical reaction activity of maize starch were investigated by analyzing the influence of mechanical activation on degree of substitution(DS)of esterification and grafting rate(G)and grafting efficiency(GE)of graft copolymerization.The results indicated that the DS,G and GE of MAMS were higher than that of native starch,and showed obviously enhanced chemical reaction activity of maize starch by mechanical activation.The crystal structure and compact granule surface of maize starch were destroyed by mechanical activation,and the crystallinity decreased from polycrystalline to amorphous.With increasing activation time,the gelatinization temperature and pastes viscosity of MAMS decreased and its fluidity was enhanced.As a consequence,the resistance of reagents diffusing into starch solution would be reduced and it was easier to diffuse into starch intramolecule.

Field of study: Chemistry, Environmental science
Resonances near thresholds and SU3 symmetry

A problem raised recently byOakes andYang is discussed within the framework of a nonrelativistic model. Arguments are presented for the purity of the wave-functions of the decuplet. The accuracy of the mass formula is discussed in terms of the widths of the resonances. A criterion is given for the applicability of the SU3 model to the calculation of cross sections and branching ratios.

Field of study: Physics
Evaluation of a mixed beam therapy for postmastectomy breast cancer patients: Bolus electron conformal therapy combined with intensity modulated photon radiotherapy and volumetric modulated photon arc therapy

The purpose of this study was to assess the potential benefits and limitations of a mixed beam therapy, which combined bolus electron conformal therapy (BECT) with intensity modulated photon radiotherapy (IMRT) and volumetric modulated photon arc therapy (VMAT), for left‐sided postmastectomy breast cancer patients.  Mixed beam treatment plans were produced for nine postmastectomy radiotherapy (PMRT) patients previously treated at our clinic with VMAT alone. The mixed beam plans consisted of 40 Gy to the chest wall area using BECT, 40 Gy to the supraclavicular area using parallel opposed IMRT, and 10 Gy to the total planning target volume (PTV) by optimizing VMAT on top of the BECT + IMRT dose distribution. The treatment plans were created in a commercial treatment planning system (TPS), and all plans were evaluated based on PTV coverage, dose homogeneity index (DHI), conformity index (CI), dose to organs at risk (OARs), normal tissue complication probability (NTCP), and secondary cancer complication probability (SCCP). The standard VMAT alone planning technique was used as the reference for comparison.  Both techniques produced clinically acceptable PMRT plans but with a few significant differences: VMAT showed significantly better CI (0.70 vs 0.53, P < 0.001) and DHI (0.12 vs 0.20, P < 0.001) over mixed beam therapy. For normal tissues, mixed beam therapy showed better OAR sparing and significantly reduced NTCP for cardiac mortality (0.23% vs 0.80%, P = 0.01) and SCCP for contralateral breast (1.7% vs 3.1% based on linear model, and 1.2% vs 1.9% based on linear‐exponential model, P < 0.001 in both cases), but showed significantly higher mean (50.8 Gy vs 49.3 Gy, P < 0.001) and maximum skin doses (59.7 Gy vs 53.3 Gy, P < 0.001) compared with VMAT. Patients with more tissue (minimum distance between the distal PTV surface and lung approximately > 0.5 cm and volume of tissue between the distal PTV surface and heart or lung approximately > 250 cm3) between distal PTV surface and lung may benefit the most from mixed beam therapy.  This work has demonstrated that mixed beam therapy (BECT + IMRT:VMAT = 4:1) produces clinically acceptable plans having reduced OAR doses and risks of side effects compared with VMAT. Even though VMAT alone produces more homogenous and conformal dose distributions, mixed beam therapy remains as a viable option for treating postmastectomy patients, possibly leading to reduced normal tissue complications.

Field of study: Medicine, Physics
Seroimmunity to poliomyelitis in hospital personnel.

Neutralizing antibody titers to poliovirus type 1, 2 and 3 were examined in paired serum specimens obtained from 43 female hospital personnel and laboratory workers at Veterans General Hospital. Before vaccination, 23.2% of those studied did not have neutralizing antibodies to one or more types of poliovirus, and 4.6%, 13.9% and 7.0% lacked serum neutralizing antibodies to poliovirus type 1, 2 and 3, respectively. In a comparison of the serological responses evoked by oral poliovirus vaccine in the same persons, a striking difference in antibodies was shown in the geometric mean titers and no lack of antibodies was found after oral poliovaccine immunization. Therefore immunization with oral poliovirus vaccine should be considered in the future as to improved protection for such high risk people.

Field of study: Biology
Risk-adjusted capitation payments: developing a diagnostic cost groups classification for the Dutch situation.

In many countries market-oriented health care reforms are high on the political agenda. A common element of these reforms is that the consumers may choose among competing health insurers or health plans, which are largely financed through premium-replacing capitation payments. Since 1993, Dutch sickness funds receive risk-adjusted capitation payments based on demographic factors. It has been shown that the predictive accuracy of a demographic capitation model improves when it is extended with diagnostic information from prior hospitalizations, in the form of Diagnostic Costs Groups (DCGs). In this study a DCG classification is developed using Dutch cost data of sickness fund members of all ages. The study also dealt with the question of how to handle high discretion diagnoses. For the Dutch situation high discretion diagnoses may be defined as those diagnoses for which day case treatment is a possible alternative for a hospital admission. Grouping persons with a hospital admission for high discretion diagnoses together with people without an admission resulted in a slight reduction of the predictive accuracy of the DCG model. Adequate risk-adjustment is critical to the success of market-oriented health care reforms. The use of diagnostic information from prior hospitalizations seems a promising option for improving the capitation formula.

Field of study: Medicine, Political science
No evidence for internal rotation in the remnant core of the Sagittarius dwarf

We have conducted a spectroscopic survey of the inner regions of the Sagittarius (Sgr) dwarf galaxy using the AAOmega spectrograph on the Anglo-Australian Telescope. We determine radial velocities for over 1800 Sgr star members in six fields that cover an area 18.84 deg{sup 2}, with a typical accuracy of {approx}2 km s{sup -1}. Motivated by recent numerical models of the Sgr tidal stream that predict a substantial amount of rotation in the dwarf remnant core, we compare the kinematic data against N-body models that simulate the stream progenitor as (1) a pressure-supported, mass-follows-light system and (2) a late-type, rotating disk galaxy embedded in an extended dark matter halo. We find that the models with little or no intrinsic rotation clearly yield a better match to the mean line-of-sight velocity in all surveyed fields, but fail to reproduce the shape of the line-of-sight velocity distribution. This result rules out models wherein the prominent bifurcation observed in the leading tail of the Sgr stream was caused by a transfer from intrinsic angular momentum from the progenitor satellite into the tidal stream. It also implies that the trajectory of the young tidal tails has not been affected by internal rotation in the progenitormore » system. Our finding indicates that new, more elaborate dynamical models, in which the dark and luminous components are treated independently, are necessary for simultaneously reproducing both the internal kinematics of the Sgr dwarf and the available data for the associated tidal stream.« less

Field of study: Physics
Transition-metal-catalyzed direct arylations via C–H bond cleavages

Palladium catalysts allowed for intermolecular direct arylations of heteroarenes with aryl chlorides, tosylates, or mesylates as electrophiles. As an economically attractive alter-native, inexpensive copper catalysts could be employed for regioselective C–H bond aryl-ations of 1,2,3-triazoles. On the contrary, intermolecular C–H bond functionalizations of arenes were accomplished with ruthenium complexes derived from air-stable (heteroatom-substituted) secondary phosphine oxide (HASPO) preligands. Particularly, the use of ruthenium(II) carboxylate complexes enabled broadly applicable direct arylations with inter alia aryl tosylates and phenols, and set the stage for unprecedented intermolecular direct alkylations with unactivated alkyl halides bearing β-hydrogens.

Field of study: Chemistry
Palaeo- and rock magnetic investigations of Late Quaternary sediments from the Upper Congo deep-sea fan: on the difficulty in obtaining palaeomagnetic secular variation records from low latitudes

We report here on results of palaeo- and rock magnetic investigations of two sediment cores from the Upper Congo deep-sea fan. The sediments have a high organic content and contain a heterogeneous Fe-mineral assemblage with biogenic magnetite and detrital (Ti-)magnetite as the main magnetic carrier minerals. Pyrite, hematite, and Fe-oxyhydroxides were identified by comparing high-temperature magnetic susceptibility curves with those from Fe-minerals of known composition. According to AMS 14C dates, the 6.8 m-long profile spans the last 37 kyr. Sediments older than 20 ka are affected by reductive diagenesis that has led to a loss of the fine-grained magnetic mineral fraction. Sediments younger than 20 ka have stable magnetizations. Characteristic remanent magnetization records of inclination and declination were obtained for each core. There is a little agreement between these records, modelled curves, and other sediment records from Equatorial Africa, so no composite record could be established. The cores are not ideal relative palaeointensity recorders and estimates using different normalizers did not yield consistent signals from both cores. Normalization methods used for relative palaeointensity estimation were not developed for sediments that contain large amounts of ultra-fine-grained biogenic magnetite; therefore, the relative palaeointensity estimates should be considered with caution. However, in view of the incoherent picture given by the scarce available palaeointensity information from the region off South-West Africa, the GeoB6517-2 record may provide a tentative relative palaeointensity record for comparison, at least for the past 10 kyr.

Field of study: Environmental science
Phase transitions and spin excitations in new multiferroics with modulated magnetic structure

Coexistence of an antiferromagnetic (modulated) structure and electric polarization has been revealed in single crystals of Eu1 − xYxMnO3 (0.2 ≤ x ≤ 0.5) and Gd1 − xYxMnO3 (0 ≤ x ≤ 0.2) manganites. Hence, these compounds can be considered as a new family of multiferroics. Various phase transitions, both spontaneous and induced by magnetic fields up to 250 kOe, accompanied by anomalies in magnetization, magnetostriction, permittivity, and electric polarization, have been found, and phase T-x diagrams have been constructed. In the submillimeter range (8–40 cm−1), new spin excitations—electromagnons—have been revealed; they are excited by an electric field. It is established that suppression of the modulated structure by a magnetic field leads to the disappearance of electromagnons; this process is accompanied by significant changes in the permittivity in a wide frequency range.

Field of study: Physics
Effects of fimbria-fornix, hippocampus, and amygdala lesions on discrimination between proximal locations.

The conditioned cue preference (CCP) task was used to study the information required to discriminate between spatial locations defined by adjacent arms of an 8-arm radial maze. Normal rats learned the discrimination after 3 unreinforced preexposure (PE) sessions and 4 food paired-unpaired training trials. Fimbria-fornix lesions made before, but not after, PE, and hippocampus lesions made at either time, blocked the discrimination, suggesting that the 2 structures processed different information. Lateral amygdala lesions made before PE facilitated the discrimination. This amygdala-mediated interference with the discrimination was the result of a conditioned approach response that did not discriminate between the 2 arm locations. A hippocampus/fimbria-fornix system and an amygdala system process different information about the same learning situation simultaneously and in parallel.

Field of study: Biology, Psychology
ELASTO-PLASTICITY ANALYSIS OF BRIDGE ACCOUNTING FOR SPATIAL VARIABILITY OF EARTHQUAKE MOTIONS AND BRIDGE PILE-PIERS-SOIL INTERACTION: THEORY, METHOD, PROGRAM AND INTELLIGENT MODELLING

Numerical studies on seismic responses of a long-span bridge pier-pile-soil system relate with the following several aspects: the reasonability and convenience of the finite element model for a long-span bridge pier-pile-soil system, the validity of approach for multi-point earthquake motions at underground locations, the wave force and effect of hydrodynamic pressures-induced added mass; and multi-source visco-elastic artificial boundary conditions. Firstly, the essential difference between the long-span bridge pier-pile-soil system with and without artificial boundary conditions is expounded and pointed out. Then, a feasible and effect path for the inversion of earthquake motions is given and proposed, accounting for spatial variability, at under-ground location from ground surface, and the corresponding visible program called MEMS_c(Multiple Earthquake Motions Simulation_c) is further developed successfully. Further, a visual program named WFS(Wave Force Simulation) is developed and illustrated based on the wave force and its spectral characteristics for small-scale structures. At last, in order to improve the efficiency and flexibility of preprocessor, a quick workflow for establishing numerical modeling is presented and the visual modeling tool Foundation 2013.6 is developed. The content involves theory and practicability. It can be directly applied to the follow-up engineering.

Field of study: Engineering
SU‐EE‐A3‐03: Comparison of CBCT and Electromagnetic Transponders for Prostate Localization

In prostate cancerradiotherapy, it is unknown how large the PTV margins must be to account for the isocenter correction tolerance and intrafraction motion. The risk of geographic miss can be minimized by the placement of fiducial markers in the prostate gland for daily pretreatment localization and adjustment of patient position if necessary. In this study, we assess the magnitude of interfraction and intrafraction isocenter displacement using implanted electromangnetic transponders, and validate the accuracy of interfraction localization using cone beam CT.Method and Materials: Fifteen supine prostate IMRT patients with three implanted transponders each were studied. Initial daily localization was based on three laser and skin marks. Daily localization error distribution was determined from offsets between the initial setup position and that determined by Calypso. Post setup with the Calypso system, isocenter localization was immediately independently verified by imaging the radio‐opaque transponders using an integrated cone beam CTimaging system. Both localization techniques produced lateral, longitudinal, and vertical target offsets from machine isocenter. Organ motion or patient movement during treatment was continuously monitored by the Calypso system at a 4‐mm threshold.  The mean interfraction displacement (± SD) in cm in the lateral, vertical, and longitudinal directions were −0.2 ± 0.6, 1.8 ± 1.3, and 0.3 ± 0.9, respectively. After any necessary isocenter corrections, the mean isocenter placement error relative to the cone beam CT (± SD) in cm in the lateral, vertical, and longitudinal directions were 0.0 ± 0.1, 0.1 ± 0.2, and 0.0 ± 0.1, respectively.  Compared with use of skin marks, electromagnetic isocenter repositioning provides an increased degree of isocenter localization. Good agreement was observed between cone beam CT isocenter localization and electromagnetic repositioning. However, the electromagnetic technique, with real time continuous tracking, has the added advantage of threshold‐based intervention with no additional radiation dose.

Field of study: Medicine, Physics
Electrical Resistance and Microstructural Changes of Silver–Epoxy Isotropic Conductive Adhesive Joints Under High Humidity and Heat

In this study, the degradation mechanism of chip resistors mounted with Ag–epoxy isotropic conductive adhesive (ICA) under two different environmental conditions, i.e., humidity exposure (85°C/85% relative humidity) and thermal cycling (TC, –40°C to 125°C), was examined by monitoring the change in electrical resistance and by transmission electron microscopy. The effect of the terminal finishes (Sn/Ni or Au/Ni) of the chip components on joint stability during those two tests was also examined. The electrical resistance of the Sn/Ni-plated chip component joined with Ag–epoxy ICA during both environmental tests increased with exposure time. On the other hand, the electrical resistance of the Au/Ni-plated chip component joined with Ag–epoxy ICA remained unchanged during both tests. In the case of the Sn/Ni-plated chip joint, Sn oxides such as SnO, SnO2, and Sn-Cl-O were formed inhomogeneously on the surface of the Sn plating during the humidity exposure test. Under the TC test, microcracks were also observed at the Sn/epoxy and the Ag filler/epoxy interfaces. A Ni3Sn intermetallic compound (IMC) was formed at the interface between Sn and Ni, and the Ni3Sn4 IMC was also formed at the Sn surface. In contrast, no oxide was found in the Au/Ni-plated chip joint during the humidity exposure test. Also, no IMC was found in that joint during the TC test. It is suggested that oxides, microcracks, and IMCs cause the electrical degradation of Sn/Ni-plated chip components joined with Ag–epoxy ICA.

Field of study: Materials science
A Novel Cell Irradiation System Using 90$^{\circ}$-Scattering Technique

A novel cell irradiation system was developed for use with the HVEE Van de Graaff accelerator at the National Tsing Hua University. A 90°-scattering technique using an Au foil was designed, in which charged particles were directed from horizontal to vertical irradiation. Beam performance was tested with a silicon detector and a CR-39 nuclear track detector. The HeLa cells were irradiated with 2-MeV alpha particles and the formation of giant cells was observed. The result showed that this system provides a convenient way of generating a vertical particle beam and a cell-supporting chamber, thereby allowing a suitable cell growth condition during irradiation. Furthermore, establishment of such a system is more convenient and economical than the alternatives.

Field of study: Physics
Current and future prospects of enhanced heat transfer in ammonia systems

In the last decade a moderate headway has been made in the application of enhanced surface heat exchangers in ammonia refrigeration systems. This has been a result of the persistent issue of ozone and global warming which has resulted in keen interest in natural refrigerants such as ammonia that has played a prominent role in the refrigeration industry for years, particularly in the field of food, beverage and marine. The only drawback with ammonia is the toxicity; hence, if smaller heat exchangers could be introduced in order to reduce ammonia charge, this negative aspect about ammonia can be addressed to a great extent. In order to achieve this goal, novel and compact heat exchangers with enhanced surfaces have to be introduced. This paper presents an over view of the status of ammonia as a refrigerant and discusses the present and the future trends in the development of compact heat exchangers for use in ammonia refrigeration.

Field of study: Engineering
Jackknifing a Convex Combination of One-Sample U-Statistics

As an estimator of an estimable parameter, we consider a convex combination of U-statistics (Toda and Yamato, 2001) Yn which includes U-statistic, V-statistic, S-statistic, and limit of Bayes estimate. We introduce the bias-reduced jackknifed estimator based on this convex combination. This statistic is written as a linear combination of U-statistics. From this, we know that jackknifed version of the V-statistic is not equal to the U-statistic for the degree more than or equal to three. To see the effects of jackknifing the statistic Yn, we show the difference between Yn and by the second-order deficiency. By second-order deficiency, we can not see the difference between Un and and between different two 's. Therefore, we show the differences between them by the fourth-order deficiency. We also give some examples using the V-statistic, limit of Bayes estimate, and S-statistic.

Field of study: Mathematics
Rubisco specificity factor tends to be larger in plant species from drier habitats and in species with persistent leaves

The specificity factor of Rubisco is a measure of the relative capacities of the enzyme to catalyse carboxylation and oxygenation of ribulose 1,5-bisphosphate and hence to control the relative rates of photosynthetic carbon assimilation and photorespiration. Specificity factors of purified Rubisco from 24 species of C3 plants found in diverse habitats with a wide range of environmental growth limitations by both water availability and temperature in the Balearic Islands were measured at 25°C. The results suggest that specificity factors are more dependent on environmental pressure than on phylogenetic factors. Irrespective of phylogenetic relationships, higher specificity factors were found in species characteristically growing in dryer environments and in species that are hemideciduous or evergreen. Effects of temperature on specificity factor of the purified enzyme from 14 species were consistent with the concept that higher specificity factors were associated with an increase in the activation energy for oxygenation compared to carboxylation of the 2,3-enediolate of RuBP to the respective transition state intermediates. The results are discussed in terms of selection pressures leading to the differences in specificity factors and the value of the observations for identifying useful genetic manipulation to change Rubisco polypeptide subunits.

Field of study: Environmental science