nils-herrmann/clean_scirepeval huggingface dataset:
The Impact of Escape Alternative Position Change in Multiple-Choice Test on the Psychometric Properties of a Test and it's Items Parameters

This study aimed at investigating the impact changing of escape alternative position in multiple-choice test on the psychometric properties of a test and it's items parameters (difficulty, discrimination & guessing), and estimation of examinee ability. To achieve the study objectives, a 4-alternative multiple choice type achievement test consisting of 39 items in psychological and educational measurement and evaluation was constructed. The test had four different forms according to the escape alternative position. The statistical software Bilog - MG3 was used to analyze the responses of the total sample (1521) examinees according to the three parameter logistic model (3PLM) of item response theory (IRT). The results of the study revealed that there were statistically significant differences in the means of item parameters (difficulty & discrimination) between the first and the fourth forms, due to the changing of escape alternative position; the differences were in favor of the four form. The results also showed there were statistically significant differences in the means of examinee ability between the first and the fourth forms, due to the changing of escape alternative position; the differences were in favor of the fourth form, and there were no statistically significant differences between other forms. The results also revealed there were statistically significant differences among criterion validity coefficients in favor of form four of the test. Finally, significant differences were noticed in the value of empirical reliability coefficients in favor of the fourth form.  Multiple-Choice Tests, Escape Alternatives, Item Response Theory .

Field of study: Education
Model of Reconfigurable Computing System

The MorphoSys M1 proposed by University of California,Irvine is a typical example of the coarse-grained reconfigurable computing system,which has good performance in the field of multimedia applications although it has some deficiencies.In this paper,we present a new reconfigurable model to overcome the main deficiency of MorphoSys M1.According to the experiment results,the improved model can speed up the performance of some multimedia applications and encryption/deencryption by 16% at least.

Field of study: Computer science
One‐Step Stereospecific Strategy for the Construction of the Core Structure of the 5,11‐Methanomorphanthridine Alkaloids in Racemic as well as in Optically Pure Form: Synthesis of (±)‐Pancracine and (±)‐Brunsvigine

The unique core structure of the complex pentacyclic 5,11-methanomorphanthridine has been constructed stereospecifically in one step by an intramolecular [3+2] cycloaddition of a non-stabilized azomethine ylide (AMY), generated by the sequential double desilylation of 14 using Ag I F as a one-electron oxidant. The formation of the single diastereomer in the key step is explained by the preferred transition state produced by endo attack of the AMY on the "Re" face of the dipolarophile. An asymmetric version of the cycloaddition using a chiral dipolarophile was applied to construct the core structure 68 with 63% ee. This strategy was successfully applied to the formal synthesis of (±)-pancracine and the total synthesis of (±)-brunsvigine. An unprecedented and interesting skeletal rearrangement product 49 was observed during the attempted assembly of the E ring from 46 through Horner-Wadsworth-Emmons reactions. Mechanisms involving azetidinium salt formation or the Grob-type fragmentation are advanced to explain the observed rearrangement.

Field of study: Chemistry
The Tethyan Pacific during Late Jurassic and Cretaceous times

During Mesozoic times, the Pacific Ocean occupied almost an entire hemisphere, plus a great wedge of ocean that lay between eastern Gondwana and Laurasia and extended westward from the Pacific into the gradually widening Tethys sea in the Mediterranea, Atlantic, and Gulf of Mexico. As the Atlantic widened, the Pacific narrowed apace, and the Pacific Plate expanded at the expense of bordering plates. During the Late Jurassic and Cretaceous, connections between the Atlantic and Pacific, via passageways between small continental plates in Central America, gradually widened, permitting a globe-circling, mainly west-flowing current system in low latitudes. Except for tectonic slices preserved along the adjacent American and Asian continents, all pre-Jurassic Pacific oceanic sediments have been subducted. Middle and Late Jurassic oceanic crust is inferred from magnetic data, and one drill hole reached Middle Jurassic crust. Pacific Cretaceous pelagic sedimentary rocks are typically nannofossil limestone above the calcite compensation depth and brown, zeolitic clay and radiolarian mudstone below. Chert is common as nodules in both limey and clayey sediments, and siliceous sediments appear to have been deposited over a wide band of latitudes in the Cretaceous. Lower Cretaceous black shale is present on several plateaus, at paleodepths of 500–1500 m, but contemporaneous sediments in adjacent basins are oxidized. Cretaceous vulcanism was on a stupendous scale: in the western equatorial Pacific, a region of about 4x106 km2, centered on the Ontong Java Plateau, is covered almost entirely by mid-plate tholeiitic flood basaltic flows and sills, probably emplaced mainly during the earliest Aptian. Emplacement of these huge masses in a relatively short time may have had important consequences not only for global sea level, but also for the chemistry of the oceans and atmosphere. A striking link to Tethyan facies in the other hemisphere is the presence of shallow-water platform and reefal sediments on the summits of many Pacific Cretaceous seamounts. Several dozen Early Cretaceous seamounts built to heights above sea level, and doubtless many more existed on crust now subducted along the margins of the Pacific. As the seamounts subsided, shallow-water rudist/coral platforms gradually covered them, eventually forming atolls. The platforms are the Pacific expression of the “Urgonian” platforms of the Tethys. Many—perhaps most—of the Pacific Early Cretaceous platforms drowned in the latest Albian, and are guyots today. New volcanic chains rose later in the Cretaceous, but there is a gap in rudist reef development from the Cenomanian through the Santonian. Campanian and Maestrichtian rudist reefs flourished in equatorial latitudes, but hermatypic reefs appear to have been absent during the Paleocene.

Field of study: Environmental science, Geography
Solid-phase cadmium speciation in soil using L3-edge XANES spectroscopy with partial least-squares regression.

Cadmium (Cd) has a high toxicity and resolving its speciation in soil is challenging but essential for estimating the environmental risk. In this study partial least-square (PLS) regression was tested for its capability to deconvolute Cd L(3)-edge X-ray absorption near-edge structure (XANES) spectra of multi-compound mixtures. For this, a library of Cd reference compound spectra and a spectrum of a soil sample were acquired. A good coefficient of determination (R(2)) of Cd compounds in mixtures was obtained for the PLS model using binary and ternary mixtures of various Cd reference compounds proving the validity of this approach. In order to describe complex systems like soil, multi-compound mixtures of a variety of Cd compounds must be included in the PLS model. The obtained PLS regression model was then applied to a highly Cd-contaminated soil revealing Cd(3)(PO(4))(2) (36.1%), Cd(NO(3))(2)·4H(2)O (24.5%), Cd(OH)(2) (21.7%), CdCO(3) (17.1%) and CdCl(2) (0.4%). These preliminary results proved that PLS regression is a promising approach for a direct determination of Cd speciation in the solid phase of a soil sample.

Field of study: Physics
Fast Multipole Methods for Simulating Collisional Star Systems

Direct $N$-body simulations of star clusters are accurate but expensive largely due to the numerous $\mathcal{O} (N^2)$ pairwise force calculations. State-of-the-art $N$-body codes can take nearly 6 months of computer wall time to simulate a single $N=10^6$ globular cluster over a single relaxation time. To solve the post-million body problem, it will be necessary to use approximated force solvers, such as tree codes. In this work, we adapt a tree-based, optimized Fast Multipole Method (FMM) to the collisional $N$-body problem. The use of a rotation-accelerated translation operator and an error-controlled cell opening criteria leads to a code which can be tuned to arbitrary accuracy. We demonstrate that our code, Taichi, can be as accurate as direct summation when $N> 10^4$. This opens up the possibility of performing large-$N$, star-by-star simulations of massive stellar clusters, and would permit large parameter space studies that would require years with the current generation of direct summation codes. Using a series of tests and idealized models, we show that Taichi can accurately model collisional effects, such as dynamical friction and the core-collapse time of idealized clusters, producing results in strong agreement with benchmarks from other collisional codes such as NBODY6++GPU or PeTar. Parallelized using OpenMP and AVX, Taichi is nearly 70 times faster on a 28-core single machine than its direct integration counterpart. With future improvements to the handling of close encounters and binary evolution, we clearly demonstrate the potential of an optimized FMM for the modelling of collisional stellar systems, opening the door to accurate simulations of massive globular clusters, super star clusters, and even galactic nuclei.

Field of study: Physics
Ontogenetic symmetry and asymmetry in energetics

Body size ($$\equiv $$ biomass) is the dominant determinant of population dynamical processes such as giving birth or dying in almost all species, with often drastically different behaviour occurring in different parts of the growth trajectory, while the latter is largely determined by food availability at the different life stages. This leads to the question under what conditions unstructured population models, formulated in terms of total population biomass, still do a fair job. To contribute to answering this question we first analyze the conditions under which a size-structured model collapses to a dynamically equivalent unstructured one in terms of total biomass. The only biologically meaningful case where this occurs is when body size does not affect any of the population dynamic processes, this is the case if and only if the mass-specific ingestion rate, the mass-specific biomass production and the mortality rate of the individuals are independent of size, a condition to which we refer as “ontogenetic symmetry”. Intriguingly, under ontogenetic symmetry the equilibrium biomass-body size spectrum is proportional to 1/size, a form that has been conjectured for marine size spectra and subsequently has been used as prior assumption in theoretical papers dealing with the latter. As a next step we consider an archetypical class of models in which reproduction takes over from growth upon reaching an adult body size, in order to determine how quickly discrepancies from ontogenetic symmetry lead to relevant novel population dynamical phenomena. The phenomena considered are biomass overcompensation, when additional imposed mortality leads, rather unexpectedly, to an increase in the equilibrium biomass of either the juveniles or the adults (a phenomenon with potentially big consequences for predators of the species), and the occurrence of two types of size-structure driven oscillations, juvenile-driven cycles with separated extended cohorts, and adult-driven cycles in which periodically a front of relatively steeply decreasing frequencies moves up the size distribution. A small discrepancy from symmetry can already lead to biomass overcompensation; size-structure driven cycles only occur for somewhat larger discrepancies.

Field of study: Biology, Mathematics
Measurements of emittance and absolute spectral flux of the PETRA undulator at DESY Hamburg.

The first synchrotron radiation beamline using a 4 m-long undulator at the 12 GeV storage ring PETRA delivers hard X-ray photons usable up to 300 keV. The photon intensity is measured on an absolute scale in the energy range between 16 and 60 keV and compared with calculated intensities. The experimental set-up described is also used to measure the horizontal and vertical emittance of the source.

Field of study: Physics
Evaluation on MAM copolymer as oil well cement retarder

Retarder MAM is prepared from copolymerization of 2-acrylamide-2-methyl-opanesulfonic acid(AMPS) and maleic acid(MA).The optimum technology processes to prepare MAM are investigated using orthogonal experiment;the structure of the product which is synthesized in optimum thickening time is tested and verified by FT-IR.The thickening time,compression strength of cement slurry is tested using the thickening test,strength-resistant test and salt-resistance test.The compression strength of cement rock added a certain amount of retarder is greater than the standard of 14 MPa(SY-T5504-2005 estimative methods of oil well cement retarder) after 24 h.The results show that the good effects of thickening performances can be obtained under the optimum reaction conditions of reaction temperature 70 ℃,reaction time 4 h,n(AMPS)∶n(MA) 2∶1,mass faction of initiator 1%.

Field of study: Chemistry, Environmental science
Defect-correction multigrid methods for nonlinear problems

Auzinger and Stetter  combine a multigrid method with defect-correction iteration and derive a composite iterative procedure which they call the DCMG (defect-correction multigrid) cycle. Using a high-order discrete operator in the coarsegrid correction and a lower-order operator in relaxation, the DCMG cycle achieves the higher-order approximation . In an analogous way, DCMG can be used to solve nonlinear PDEs by using the nonlinear operator in correction and a related linear operator in relaxation. We prove convergence of such a DCMG scheme and give an error estimation.

Field of study: Mathematics
Multiple antigenic peptides facilitate generation of anti‐prion antibodies

Recent reports have demonstrated the ability of anti‐prion antibodies to inhibit PrPSc propagation. Due to the relatively poor immunogenic properties of both PrPC and PrPSc, the generation of anti‐prion antibodies still causes a significant problem in the development of immunotherapeutic strategies. This study examines the potential of multiple antigenic peptides (MAPs) to raise an antibody response to prion derived sequences in mice. The MAP was constructed of a four spiked ring. Two spikes containing human or mouse derived prion amino acid sequences and two spikes containing the universally promiscuous tetanus toxoid sequence (aa 830–844) which was used to assist T‐cell‐dependent B‐cell antibody production. Following vaccinations with the MAP or MAP plus adjuvant, sera were taken and antibody titres assessed. The MAP containing only the mouse sequence failed to elicit a significant antibody response. MAPs containing human prion sequences elicited antibody production to the corresponding prion sequence. Further analysis also demonstrated that these peptides were able to generate antibody responses that recognize conserved human and mouse sequences. These homologous sequences contain the heralded PrPSc specific sequence ‘Tyr‐Tyr‐Arg’ and therefore these MAPs may have some therapeutic potential.

Field of study: Biology, Medicine
Montra: A large-scale DHT traffic monitor

This paper presents a new technique, called Montra, for accurately capturing traffic in a widely deployed DHT. The basic idea is to make the traffic monitors minimally visible to participating peers to avoid disruption in the system. We describe how Montra leverages the required redundancy in published content and routing to minimize disruption of the system. Validations of Montra over two widely deployed DHTs, namely Kad and Azureus, show that it can accurately capture more than 90% of traffic destined to monitored peers. Furthermore, the lightweight nature of Montra allows it to monitor a large number of peers with a moderate amount of resources. We use Montra to characterize several aspects of traffic in our two target DHTs.

Field of study: Computer science
Model development and validation of a solar cooling plant

This paper describes the dynamic model of a solar cooling plant that has been built for demonstration purposes using market-available technology and has been successfully operational since 2001. The plant uses hot water coming from a field of solar flat collectors which feed a single-effect absorption chiller of 35 kW nominal cooling capacity. The work includes model development based on first principles and model validation with a set of experiments carried out on the real plant. The simulation model has been done in a modular way, and can be adapted to other solar cooling-plants since the main modules (solar field, absorption machine, accumulators and auxiliary heater) can be easily replaced. This simulator is a powerful tool for solar cooling systems both during the design phase, when it can be used for component selection, and also for the development and testing of control strategies.

Field of study: Engineering
The Arabian continental alkali basalt province: Part I. Evolution of Harrat Rahat, Kingdom of Saudi Arabia

The Harrat Rahat lava field forms a major component of an extensive but poorly known continental alkali basalt province extending from Yemen in the south, through Saudi Arabia and Jordan, to Syria in the north. The continental intraplate volcanism which produced the Arabian lava fields (harrats) was contemporaneous with opening of the Red Sea, collision of the Arabian and Eurasian plates, and uplift of the Afro-Arabian dome.

Harrat Rabat has evolved over the past 10 m.y. It contains two prominent lateritic disconformities which separate three stratigraphic units: the Shawahit (10-2.5 Ma), Hammah (2.5-1.7 Ma), and Madinah (1.7-Recent) basalts, comprising 68%, 19%, and 13% of the total harrat volume, respectively. The Shawahit basalt is composed of coarse-grained, dictytaxitic olivine transitional basalt (OTB) and minor (∼10%) alkali olivine basalt (AOB) which erupted through scoria cones and shield volcanoes. In contrast, the Hammah basalt is dominated by equal volumes of fine-grained, intergranular-to-intersertal AOB and hawaiite which erupted mainly through scoria cones and relatively few shield volcanoes. Sparse domes and flows of mugearite and benmoreite first appear in the Hammah basalt. The Madinah basalt spans the full compositional range of Harrat Rahat; 103 analyzed samples comprise OTB (8%), AOB (47%), hawaiite (32%), mugearite (4%), benmoreite (8%), and trachyte (2%). Here scoria cones dominate, whereas shield volcanoes are sparse and occur only in the lower Madinah basalt; domes and associated pyroclastic deposits are common. The final events of harrat volcanism include 11 "post-Neolithic" eruptions (<4,500 yr old) and two historical eruptions (in 641 and 1256 A.D.).

Arabian harrat magmatism may have been initiated by partial melting of garnet perido-tite in the asthenosphere at a depth > 100 km. Accumulation of this partial melt at the crust-mantle boundary (37-44 km) may have resulted in Miocene uplift of the Afro-Arabian dome. Harrat Rahat volcanism began shortly after significant initial uplift with the voluminous extrusion of Shawahit OTB lava. Chemical and petrographic data suggest that these OTB magmas ascended rapidly, with little crustal residence time. The data support a model of open-system fractionation for AOB and hawaiite lavas of the younger Hammah and Madinah basalts. In this model, some of the potential Shawahit OTB was trapped in crustal chambers during magma ascent. Crystal fractionation in these chambers was accompanied by their periodic replenishment by rising OTB magma. This resulted in the mixing of magma types and the development of AOB and hawaiite magmas which are anomalously enriched in highly incompatible elements. The mugearite, benmoreite, and trachyte lavas are the products of advanced fractionation in these crustal chambers with little or no magma replenishment.

Field of study: Geology
Identification of rat serotonin 5-HT2C receptors as glycoproteins containing N-linked oligosaccharides.

Antibodies against a portion of the rat 5-HT2C receptor third intracellular loop were generated and used to identify receptors solubilized from cell lines and rat brain. Western blots of CHAPS-soluble proteins were probed with affinity-purified anti-2C antibodies. The specificity of anti-2C was demonstrated with extracts prepared from NIH/3T3 fibroblasts which stably express functional rat 5-HT2C or 5-HT2A receptors. Extracts from the 5-HT2C cell line, but not the 5-HT2A cell line, contained immunoreactive proteins with masses of 51-52 kDa and 58-68 kDa. In the brain, immunoreactive proteins were identified from choroid plexus extracts with masses of 51 kDa and 58-62 kDa. The major 58-62 kDa and minor 51 kDa proteins were not detected in extracts prepared from the hippocampus, striatum, or frontal cortex using the same amount of CHAPS-soluble protein. These results are consistent with previous studies demonstrating that 5-HT2C receptor binding sites and mRNA are most abundant in choroid plexus. The association of asparagine-linked (N-linked) oligosaccharides with the receptors was examined next. The 5-HT2C receptor cell line (3T3/2C) was grown in the presence of tunicamycin to metabolically inhibit N-linked glycosylation. Proteins from the cell extracts were detected with masses of 40 and 41 kDa. Extracts prepared from 3T3/2C cells (grown in the absence of tunicamycin) and from choroid plexus were incubated with N-glycosidase F to enzymatically remove available N-linked sugars. Immunoreactive proteins were detected with masses of 41 and 42 kDa from 3T3/2C cells and 41 kDa from choroid plexus. Neuraminidase, which cleaves sialic acid (N-acetylneuraminic acid) residues from glycoproteins, reduced the mass of the 51 and 58-62 kDa proteins from the choroid plexus to 50 and 54-58 kDa. In contrast, the 51-52 and 58-68 kDa proteins from 3T3/2C cells were not affected by treatment with neuraminidase. These results demonstrate that 5-HT2C receptors contain N-linked sugars and suggest that sialic acid residues associate with 5-HT2C receptors in the choroid plexus. The oligosaccharide moieties, which contribute up to approximately 30% of the relative mass as judged by SDS-polyacrylamide gel electrophoresis, may impart functional properties to 5-HT2C receptors.

Field of study: Biology
Introduction to Intertemporal Equilibrium Theory: Indeterminacy, Bifurcations, and Stability

Institute of Economic Research, Kyoto University, Yoshida Honmachi,Sakyoku, Kyoto 606, Japannishimurakier.kyoto-u.ac.jpThis paper provides an overview of the basic concepts of intertemporal equi-librium theory, and discusses the frameworks and techniques used in this subject.It then goes on to introduce the main themes discussed in the papers included inthis symposium issue.

Field of study: Economics