nils-herrmann/clean_scirepeval huggingface dataset:
SU-E-T-189: Commission Range Shifter On a Spot Scanning Proton System Using Raystation Treatment Planning System

To treat superficial target e.g. chest wall, head&neck or cranial cases, we commissioned two range shifter(RS) in Raystation4.0 with 7.37cm(RS1) and 4.1cm(RS2) Water Equivalent Thickness(WET) respectively. However, current beam model has limitations due to the secondary scattered proton. This study provides a detailed and critical commission data and provides suggestions for using RS in clinic.  RS’ WET was verified by Multi-Layer Ionization Chamber from 120MeV to 226.7MeV before TPS modeling. Spot characteristics were measured using 2D scintillate detector at ISO with different air gap. A 8×8×10cm3 cube is created in 8cm depth of water to verify the absolute dose accuracy. Plans were created with different air gap using both RS. Absolute dose verification was measured along the central axis from distal end to surface using PPC05. 10 clinical RS2 plans were measured using MatriXXPT in 3 planes (proximal, distal and midSOBP).  RS material’s proton stopping power is energy dependent(from 70MeV to 226.7MeV) ranging from 7.42 to 7.31cm and from 4.10 to 4.03cm respectively. We chose 7.37cm (RS1) and 4.10cm (RS2) to favor the low and median proton energy. With different air gap(3cm to 32cm), spot size expands from 3.2mm to 5.5mm(RS1) and from 3.1mm to 4.1mm(RS2) respectively(226.7MeV in air, 1-sigma). For the absolute dose verification, the larger air gap and shallower depth causes larger discrepancy between TPS and measurements. All 10 clinical plans with 5–10cm air gap passed gamma index 95% with 3%/3mm criteria and outputs differences were within 3%.  We strongly recommend each institution to verify the WET independently and choose the value to fit the clinical needs. To minimize the output difference in Raystation4.0 while avoid potential collision to the patient, we recommend to use 5–10cm air gap to minimize the output difference within 2% and preferably use RS with smaller WET if possible.

Field of study: Medicine, Physics
Topological Dislocations and Mixed State of Charge Density Waves.

We discuss the possibility of the ``mixed state'' in incommensurate charge density waves with three-dimensional order. It is shown that the mixed state can be created by applying an electric field perpendicular to the chains. This state consists of topological dislocations induced by the external field and is therefore similar to the mixed states of superfluids (type-II superconductor or liquid Helium II). However, the peculiar coupling of charge density waves with the electric field strongly modifies the nature of the mixed state compared to the conventional superfluids. The field and temperature dependence of the properties of the mixed state are studied, and some experimental aspects are discussed.

Field of study: Physics
Purification, kinetic and thermodynamic studies of a new ribonuclease from a mutant of Aspergillus niger.

Ribonuclease was purified from Aspergillus niger SA-13-20 to homogeneity level by using (NH(4))(2)SO(4) precipitation, DEAE-cellulose anion-exchange chromatography, ultrafiltration and Sephacryl HR-200 chromatography. The molecular weight and isoelectric point of the enzyme was 40.1kDa and 5.3, respectively. The pH- and temperature-dependent kinetic parameters were determined. The RNase showed the strongest affinity with RNA as the substrate, and the highest catalytic efficiency for hydrolysis of the substrate at pH 3.5 and 65 degrees C. It exhibited Michaelis-Menten Kinetics with k(cat) of 118.1s(-1) and K(m) of 57.0 microg ml(-1), respectively. Thermodynamic parameters for catalysis and thermal denaturation were also determined. Activation energy (E(a)) for catalysis of A. niger SA-13-20 RNase was 50.31 kJ mol(-1) and free energy (DeltaG(#)), enthalpy (DeltaH(#)) and entropy (DeltaS(#)) of activation for catalysis of the enzyme at 65 degrees C were 69.76, 47.50 and -65.83 Jmol(-1)K(-1), respectively. Activation energy (E(a,d)) for denaturation of the enzyme was 200.53 kJ mol(-1) and free energy (DeltaG(d)(#)), enthalpy (DeltaH(d)(#)) and entropy (DeltaS(d)(#)) of activation for denaturation of the enzyme at 45 degrees C were 79.18 kJ mol(-1), 197.88 and 373.09 Jmol(-1)K(-1), respectively.

Field of study: Biology, Engineering
Single-walled carbon nanotubes exhibit limited transport in soil columns.

The increased production and commercial use of nanomaterials combined with a lack of regulation to govern their disposal may result in their introduction to soils and ultimately into groundwater systems. In this study, we investigated the transport behavior of carboxyl-functionalized single-walled carbon nanotubes (SWNTs) in columns packed with a natural soil. In general, SWNT deposition (filtration) rate increased with increasing solution ionic strength, with divalent cations (Ca(2+)) being more effective in increasing SWNT retention than monovalent cations (K(+)). However, SWNT deposition rate over a very wide range of monovalent and divalent cation concentrations (0.03 to 100 mM) was relatively high and changed only slightly above 0.3 mM KCl or 0.1 mM CaCl(2). In contrast, filtration of another type of engineered carbon-based nanomaterial, namely aqueous fullerene (C(60)) nanoparticles (radius of 51 nm), was more sensitive to solution ionic strength, displaying lower deposition rate and more effective transport in soil than SWNTs. These observations indicate that physical straining governs SWNT filtration and transport under all the solution chemistries investigated in the present study. It is proposed that SWNT shape and structure, particularly the very large aspect ratio and its highly bundled (aggregated) state in aqueous solutions, as well as the heterogeneity in soil particle size, porosity, and permeability, collectively contribute to straining in flow through soil media. Our results suggest that SWNTs of comparable properties to those used in the present study will not exhibit substantial transport and infiltration in soils because of effective retention by the soil matrix.

Field of study: Environmental science
Modelling and Simulation Results for a Domestic Exhaust-Air Heat Pump Heating System

Energy consumption in residential buildings has gained an increasing interest the latest years due to the rising demand for efficient energy use and higher comfort standards. In tight building constructions with controlled ventilation, heat recovery with exhaust-air heat pump connected to floor heating is regarded as energy efficient heating system that optimises the energy use in buildings while maintaining an acceptable level of thermal comfort. In this study, we use the computational tools TRNSYS and EES to model and analyse the performance of a residential house, its ventilation system and its floor heating system based on an exhaust air heat pump. The system analysis focuses particularly on the influence of internal and solar gains on the operation of the heating system and the thermal comfort of the house. Furthermore, the way that gains influences the performance of the floor heating system is examined. Overall, the results bring to light the impact of factors that are not easy to predict on the indoor climate and the thermal comfort.

Field of study: Engineering
U–Pb zircon geochronology of the Kapuskasing structural zone and vicinity in the Chapleau–Foleyet area, Ontario

Geological development of the Archean Abitibi and Wawa greenstone–granite subprovinces of the Superior Province occurred in three main stages: (1) a volcanic–sedimentary depositional stage ~2750–2696 Ma ago, (2) a metamorphic–tectonic event ~2700–2685 Ma ago, and (3) a late plutonic event at ~2685–2668 Ma. The area between Wawa in the west and Ivanhoe Lake in the east represents an oblique section through some 20 km of the crust, where geochronological relationships can be examined at different structural levels. Much of the eastern Wawa Subprovince is characterized by tonalite–granodiorite gneiss containing abundant mafic xenoliths and represents a crustal level intermediate between high-level metavolcanic rocks near Lake Superior and the deep-seated gneisses of the Kapuskasing structural zone. A tonalitic phase of the complex gneiss of the Wawa Subprovince has a minimum U–Pb zircon date of 2707 Ma but the fine zircons are partly reset, possibly in response to lit-par-lit injections of gneissic to foliat...

Field of study: Environmental science
The Synthesis and Structural Characterization of a Two-Dimensional Coordination Polymer [Co(H2O)(phen)(μ4-bta)1/2]n (H4bta = Benzenetetracarboxylic Acid)

Complex [Co(H2O)(phen)(μ4-bta)1/2]n was hydrothermally synthesized from sodium benzene-1,2,4,5-tetracarboxylate, 1,10-phenanthroline and CoCl2·6H2O, and structurally characterized by single-crystal X-ray crystallography, showing that it possesses a novel two-dimensional polymeric structure.

Field of study: Chemistry
Gaps, or the Dialectics of Inter-imperial Art: The Case of the Belgrade Surrealist Circle

This essay reflects on the challenges posed to cultural and fiction studies by cases of imperially sedimented inter-positionality: their repercussions on our understanding of lived temporalities, the strategies we use to translate this understanding into art, and the critical tools to evaluate artworks thus produced. The essay makes operational the category of inter-imperiality and tackles phenomena such as placedness, translatability, and futurity of artwork, while discussing the Yugoslav surrealists’ piece of engagement art Facing a Wall: A Simulation of the Paranoiac Delirium of Interpretation. Survey (1932), Vane Bor’s 1935 photo-series, and Marko Ristić’s 1928 anti-novel Without Measure (1928).

Field of study: Art
Pasteur se plan

Pasteurisering word meer as een honderd jaar lank al gebruik om mikroorganismes wat infeksies veroorsaak, dood te maak of te onderdruk in melk en ander voedingstowwe. Maar wat is die doel van pasteurisering, hoe werk dit en wat is die uitwerking daarvan op die voedingswaarde van melk?

Field of study: Agricultural and Food sciences
Predicting variable-speed fan performance from motor and impeller characteristics. I. Using complete motor data.

Computerized procedures were developed for selecting and matching motors and impellers for agricultural ventilation fans. Designers of variable-speed, agricultural ventilation fans may sometimes have only limited performance information on commercially available motors, especially for voltage-controlled, permanent-split capacitor motors. Theoretical performance of three-phase induction motors was applied to single-phase, permanent-split capacitor motors to develop equations for estimating motor performance at low speeds. They developed a simple estimating procedure to predict variable-speed fan performance, requiring only motor efficiency, speed, and mechanical power at peak efficiency, and starting torque (or motor speed at breakdown torque). This procedure estimates motor efficiency, triac-generated control voltage, fan airflow rate, and ventilating efficiency ratio over the entire speed range. The development of equations from theoretical relationships along with simplifying assumptions is presented. Predicted results agreed satisfactorily with laboratory measurements.

Field of study: Agricultural and Food sciences
Wind-reworked carbonates, Permo-Pennsylvanian of Arizona and Nevada

Several workers have suggested that calcareous wind-blown dunes are genetically related to rapid, glacio-eustatic fluctuations of sea level. Although such Pleistocene and Holocene deposits are widespread along low-latitude coasts, older eolian limestones are either extremely rare or have been misinterpreted as subaqueous in origin. Medium- to large-scale cross-laminated limestones of the Callville Limestone (Pennsylvanian) of southern Nevada, the correlative Manakacha and Wescogame Formations (Supai Group), and the Pakoon Limestone (Permian) of western Grand Canyon, although considered marine by earlier workers, contain several diagnostic structures indicative of an eolian origin. Cross-strata are dominantly composed of thin, inverse-graded laminae produced by the migration and climb of wind ripples. Sets of cross-strata commonly have irregular upper surfaces produced by differential wind erosion of damp or lightly cemented laminae. Southward-dipping cross-strata in these rocks are the earliest record of a paleowind system that persisted in this region well into Jurassic time. Mechanical breakage of shells, fitted fabrics, and microstylolites indicate that marine beds that are cyclically interbedded with the eolian deposits did not undergo early lithification. Echinoderm grains with abraded over-growths within eolian deposits indicate, however, that some wind-transported grains were reworked from beds, that had previously undergone fresh-water phreatic diagenesis. Gravel lags composed of macrofossils and hardground lithoclasts at the contacts between marine and eolian beds and between eolian coasts give further evidence for deflation of subaerially exposed marine deposits. Where marine units underwent extensive early lithification, there are no gravel lags or interbedded eolian deposits. Subaerially exposed marine strata were the primary source of eolian sediment. During eustatic highstands, onshore winds probably drove beach sediment landward, but, in contrast to Quaternary examples, the eolian deposits of this study do not cap shallowing-upward sequences. Beach facies are rare. During lowstands, uncemented beach facies were first to be removed by deflation. Material too coarse to be wind-transported accumulated as gravel lags. Deflation was facilitated by the lack of widespread sea-floor cementation (hardgrounds) and by an arid paleoclimate, which limited the extent of meteoric diagenesis.

Field of study: Geology
Environmental changes in the East Equatorial Pacific during the Mid Pleistocene Transition and implications for the Last Global Extinction of benthic foraminifera

The Mid Pleistocene Transition (MPT, ~1000–700 ka) represents the latest major change in the climate system, when the climate variability changed from ~ 41 to 100 kyr cycles. Changes are reflected in different components of the climate system including the marine biota. In this study we focus on studying the East Equatorial Pacific Ocean (EEP), a relevant area in the present and past climate regulation. We present a high-resolution record of benthic foraminifera from the Ocean Drilling Program Leg 202 Site 1242 (East Equatorial Pacific, 1364 m water depth) from MIS 18 to MIS 30 (716 to 1038 ka). The analysis of benthic foraminiferal assemblages allows to identify palaeoenvironments and to make inferences about the palaeoceanographic processes involved. Bottom waters were deficient in oxygen during mild glacials of Marine Isotopic Stage (MIS) 26 and 28, early MIS 23, glacial MIS 22, and the glacial-interglacial transitions of MIS 20/19 and MIS 18e/d. The overall sustained organic carbon regime suffered a major change during mid MIS 23 (890–900 ka). We interpret this change was caused by an increased influence the open ocean upwelling system of the Costa Rica Dome derivering labile organic carbon to the seafloor. Another substantial change occurred at mid MIS 19 and it is interpreted to involve a shift in the nature of the organic carbon arriving at the seafloor. This shift largely coincides with the disappearance of a group of mainly elongated benthic foraminifera, commonly known as the “Extinction Group”. Our findings suggest the arrival of a particular type of food, for which these foraminifera where not adapted, might have contributed to the final demise of this group of foraminifera in the East Equatorial Pacific.

Field of study: Environmental science, Geography
Mechanical and Surface Properties of E-beam Irradiated Polytetrafluoroethylene-Silicone Rubber Composites

Compounding electron beam irradiated polytetrafluoroethylene (PTFE or Teflon) powder with silicone rubber produced silicone rubber/PTFE composites with desired physical properties. PTFE powder was exposed to electron beam irradiation at various doses and characterized by FTIR, DSC and contact angle measurements. Irradiation of PTFE with high energy electron beam induced chain scission reactions. Irradiated PTFE showed higher degree of crystallization and lower melting point with increasing absorbed dose. Number average molecular weight of irradiated PTFE was reduced significantly at higher absorbed doses. Formation of polar groups on the surface of irradiated PTFE powder was detected by FTIR spectroscopy. The latter was also verified by measurements of water-drop contact angle, which decreased with increasing absorbed dose. Mechanical and surface properties of the composites of silicone rubber and PTFE were characterized by tensile strength, abrasion resistance and water drop contact angle measurements. All the composites containing 5–15 phr PTFE showed higher tensile strength compared to the silicone rubber. Irradiation of PTFE powder had a significant effect on improving the abrasion resistance of the silicone rubber upon addition of only 5 phr irradiated PTFE. Similar abrasion resistance was obtained with the addition of higher amounts of non-irradiated PTFE (15 phr). Water drop contact angle of the composites decreased slightly with increasing the absorbed dose of PTFE.

Field of study: Materials science
Loss compensation by spasers in metamaterials

We show that exact loss compensation can be achieved in active metamaterials containing spasers pumped over a wide range of pumping values both below and above the spasing threshold. We demonstrate that the difference between spaser operation below and above spasing threshold vanishes, when the spaser is synchronized by an external field. As the spasing threshold loses its significance, a new pumping threshold, the threshold of loss compensation, arises. Below this threshold, which is smaller than the spasing threshold, compensation is impossible at any frequency of the external field.

Field of study: Physics
A molecular model of artificial photosynthesis: Mn-Ca binuclear complex for photosynthetic oxidation of water.

The redox active component of oxygenic photosynthetic reaction center II contains metal cluster Mn4-Ca, where two H2O are oxidized to O2 and four H+ ions are liberated. A binuclear Mn-Ca metal center binding one substrate H2O on each ion is proposed to be the minimal unit of the redox center. A model for the water oxidizing metal cluster is built with molecular modeling software (HyperChem 8.0 Pro). Mn, being a transitional metal with variable valency is redox active, while Ca is redox inert. Formation and deprotonation of H2O+ on MnIII may be favorable compared to Ca. Deprotonation of H2O+ yields a stable species HO(-) on MnIV by transfer of one electron from MnIII as a consequence of first photoact. Similarly, during second photoact, it may lead to formation of MnV = O. The O-O bond may be formed in the third photoact between O on Mn and H2O on Ca. Subsequently, HO2*(-) may be formed, leading to formation of O2. Molecular models are built for each transition states.

Field of study: Biology, Chemistry, Physics
Growth method, composition, and defect structure dependence of mercury diffusion in CdxHg1–xTe

Mercury radiotracer diffusion results are presented, in the range 254 to 452°C, for bulk and epitaxial CdxHg1–xTe, and we believe this to be the first report for metalorganic vapor phase epitaxy (MOVPE) grown CdxHg1–xTe. For all growth types studied, with compositions of xCd=0.2±0.04, the variation of the lattice diffusion coefficient, DHg, with temperature, under saturated mercury partial pressure, obeyed the equation: DHg=3×10−3 exp(−1.2 eV/kT) cm2 s−1.It was found to have a strong composition dependence but was insensitive to changes of substrate material or crystal orientation. Autoradiography was used to show that mercury also exploited defect structure to diffuse rapidly from the surface. Dislocation diffusion analysis is used to model defect tails in MOVPE CdxHg1–xTe profiles.

Field of study: Materials science
Subjective probability over a subjective decision tree

A state space has been assumed as a primitive for modeling uncertainty, which presumes that the analyst knows all the uncertainties a decision maker (DM) perceives. This is problematic because states are private information of the DM, and hence are not directly observable to the analyst. Dekel et al. [Representing preferences with a unique subjective state space, Econometrica 69 (2001) 891–934] derive, rather than assume, the subjective state space from preference over suitable choice objects. In a dynamic setting, a decision tree, that is, a pair consisting of a state space and a filtration, has been taken as a primitive. This assumption is also problematic—a decision tree should be derived rather than assumed as a primitive. We formulate a three-stage extension of the above literature in order to model a DM who anticipates subjective uncertainty to be resolved gradually over time. We identify also subjective beliefs on the subjective state space.

Field of study: Economics
Spectroscopic and lasing properties of lanthanum neodymium magnesium hexaaluminate

An investigation was made of the physicochemical, spectroscopic, and lasing properties of lanthanum neodymium magnesium hexaaluminate single crystals. It was found that concentration quenching of the neodymium luminescence was fairly weak in these crystals. Lasing in these crystals was studied in the 1.06 μ range at 300 K. Prospects for using hexaaluminate in laser technology are discussed.

Field of study: Engineering, Physics
Estimation of Pr(X<Y) in the exponential case with common location parameter

This paper considers the problem of estimating the probability P = Pr(X < Y) when X and Y are independent exponential random variables with unequal scale parameters and a common location parameter. Uniformly minimum variance unbiased estimator of P is obtained. The asymptotic distribution of the maximum likelihood estimator is obtained and then the asymptotic equivalence of the two estimators is established. Performance of the two estimators for moderate sample sizes is studied by Monte Carlo simulation. An approximate interval estimator is also obtained.

Field of study: Mathematics