nils-herrmann/clean_scirepeval huggingface dataset:
A Novel Computer Virus Model and Its Stability

Computer virus is a malicious code which can causes great damage. A SEIR model is proposed which considered that the newly entered computer in the network has been infected by other ways. It is concerned with the constant immigration, which includes susceptible, exposed and infectious, the threshold and equilibrium of this model are investigated. The locally and globally asymptotical stable results of virus-free equilibrium and viral equilibrium were being proved. Finally, some numerical examples are given to demonstrate the analytical results

Field of study: Computer science
North America's largest dinosaur trackway site: Implications for Morrison Formation paleoecology

Little-known exposures of the Upper Jurassic Morrison Formation from the Purgatoire Valley of southeastern Colorado have yielded the world's largest continuously mapped assemblage of dinosaur trackways. Body fossils include plant, invertebrate, and vertebrate remains indicative of predominantly fresh-water conditions. The tracks occur in a lacustrine sequence characterized by (1) shallow-water shales; (2) micritic shoreface limestones with ooids, intraclasts, ripple marks, mud cracks; and (3) minor quartzose sandstone with salt-crystal casts. Analysis of these sedimentary facies suggests that in southeastern Colorado, lakes were larger and longer lived than in other Morrison paleoenvironments.

Trackway orientations and footprint-depth contours pinpoint the location of the paleoshoreline at successive levels in the section. Detailed mapping of 1,300 footprints in bed 2 has revealed more than 100 trackways which testify to the activity of both quadrupedal and bipedal dinosaurs. The respective ratio based on trackway counts is ∼40/60. The quadrupedal tracks are attributed to sauropods, and represent the first ever discovered in North America. They also exhibit the first known manus claw impressions and are in need of formal description. More than 90% of the bipedal tridactyl prints lack claw impressions and are tentatively therefore referred to the Ornithopoda, cf. Gypsichnites possibly a Camptosaurus . The small proportion with distinct claw impressions may represent Allosaurus . Resulting estimates of species diversity (∼5) and predator-prey ratio (1:30) are in general agreement with the estimates of other authors based on skeletal remains, and they suggest that the Purgatoire River tracks may accurately reflect the composition of the dinosaur fauna. Distinctive groupings of parallel, non-overlapping trackways suggest gregarious behavior among sauropods and tridactylous forms.

Field of study: Geology
Geochemistry and origin of volcanic rocks from Tuzo Wilson and Bowie seamounts, northeast Pacific Ocean

The origin of the Tuzo Wilson Seamounts, 50 km south of the Queen Charlotte Islands, has been ascribed by various workers to either the Pratt-Welker mantle plume, which has formed the Pratt-Welker seamount chain, or the formation of a new segment of the Explorer-Juan de Fuca spreading ridge system. Abundances of major and trace elements in dredged alkali basalts from Tuzo Wilson and Bowie seamounts (360 km northwest of Tuzo Wilson Seamounts) are typical of alkaline volcanism on ocean islands associated with mantle plumes, but X7~r/X6~r ratios (0.70252-0.70258) fall within the range of mid-ocean ridge basalts (MORB) from the Explorer and Juan de Fuca ridges. Geochronological and chemical data from the Pratt-Welker, Bowie, and Tuzo Wilson seamounts suggest that the Tuzo Wilson Seamounts are in an early stage of development as a result of activity of the Pratt-Welker mantle plume but that contributions from both a depleted and an undepleted mantle source are necessary to reconcile trace-element and Sr isotope values. Modelling of rare-earth behaviour during partial melting indicates that neither the Tuzo Wilson nor Bowie basalts could be generated from a mantle source similar to that of the Explorer or Juan de Fuca MORB, unless recent metasomatism has enriched the seamounts' source region in incompatible elements.

Field of study: Environmental science
Dynamic polarization potential of 12C+12C system at molecular-resonance energies


The nuclear reaction dynamics leading to the formation of recently discovered resonance in the mutual-02+ channel of the 12C+12C inelastic scattering around Ec.m.≃ 32 MeV is studied in terms of the dynamic polarization potential (DPP) induced by the channel coupling among various excited states in 12C. The microscopic 3α cluster-model wave functions are used to generate the 12C−12C diagonal and coupling potentials in the double-folding model. It is found that DPP for the 02++ 02+ channel is an unusually strong attractive potential which even exceeds the zeroth-order folding-model potential of this channel around the nuclear surface region and that the strong coupling between the 02+ and 22+ states is predominantly responsible for the unusual DPP in this channel. The effective potential, the sum of the original folding-model potential and the attractive DPP, is found to generates resonance states in the same energy region as that of the resonance states generated by the original folding-model potential but the former states are found to be higher-nodal states having four additional radial nodes. Similar but more moderate property of DPP is also found in the entrance (elastic) channel. These results suggest that the reaction dynamics of generating the resonance in the 12C(02+) +12C(02+) channel may rather differ from that of the simple crossing of the zeroth-order molecular band generated by the potentials in the entrance and exit channels suggested by the standard band-crossing model.

Field of study: Physics
Hopf Bifurcation in a Dual Model of Internet Congestion Control System Using Dynamic Delayed Feedback

In this paper, the stabilization of a dual model of Internet congestion control system is considered. Here, by choosing the communication delay as bifurcation parameter, we study the effects of communication delay on nonlinear dynamical behavior and the condition of bifurcation occurrence. Furthermore, in order to postpone the onset of the undesirable Hopf bifurcation, the dynamic delayed feedback control method is applied to stabilize the nonlinear dynamic behaviors of the model. Theoretical analysis and numerical results show that this method provided in this paper is efficient in controlling Hopf bifurcation

Field of study: Computer science
Confinement and Coulomb interactions in Schottky-gated, laterally confined double-barrier quantum well heterostructures

The conductance of laterally confined double-barrier quantum well resonant tunnelling heterostructures is investigated. The lateral confinement is provided by a Schottky gate and can be varied in a continuous way. Data for dots with nominal diameters in the submicrometre range are reported.

Field of study: Materials science
Why Is China a High-Lambda Society?

Cultural and social values influence the level of cooperativeness in society, which in turn determines the level of lambda. Lambda (X) represents the parameter used to determine the degree of cooperativeness among a particular societal group or society. Martin Weitzman and Chenggang Xu (1994) used a prisoner's dilemma game to demonstrate the influence of cooperative culture on property rights theory. The prisoner's dilemma was originally described as a static, noncooperative game with complete information. It is static as it is only played once and is noncooperative, with decisions made simultaneously so that players cannot learn from one another or communicate (McCarty 2000, 326). Weitzman and Xu (1994) let the outcome of a prisoner dilemma game be quantified by the parameter B. This X is valued between zero and one. A high value of X, near one, means a cooperative solution, which comes close to looking as if it were the outcome cooperative collusion. A low value of X, near zero, means a noncooperative solution that is far from the cooperative solution, thus yielding low individual  The parameter X stands for the aBility of a group of people to resolve prisoners' dilemma-type free-riding problems internally, without the inclusion of explicit rules of behavior. With a X value of one, people in a group would be able to resolve free-riding problems completely internally, regardless of the size of the group. With a X value of zero, not even two people, the smallest group of people possible, can resolve the free-riding problems regardless of how much negotiation takes place. With a value of X between zero and one, people would be able to cooperate effectively when a group is sufficiently small, but they may not be able to cooperate as effectively when a group is sufficiently large (Weitzman and Xu 1994, 138). As such, X is the degree of cooperativeness in society's culture.

Field of study: Economics
Instrumental Variable Estimation of the Simple Errors-in-Variables Model

Alternative instrumental variable estimators for the slope in the simple errors-in-variables model are discussed. The maximum likelihood estimator is derived for the model in which the error covariance is known to be zero and for the model in which the error covariance is unknown. Modified maximum likelihood estimators and randomly weighted average estimators similar to those studied by Huntsberger are discussed. The limiting distributions of the estimators are presented and the estimators are compared in a Monte Carlo study.

Field of study: Mathematics
Potential Mechanisms Involved in the Anticonvulsant Effect of Walnut Extract on Pentylenetetrazole-Induced Seizure

It was the aim of this study to determine the potential effect of walnut kernel extract (WKE) on experimentally induced seizures in rats and to evaluate the role of benzodiazepines and ethosuximide (ESM) within these pathways.  Male Wistar rats were selected and divided into eight groups. Seizures were evoked by intravenous infusion of pentylenetetrazole (PTZ; 2 mg/ml/min). In combination with PTZ, animals were treated with vehicle or WKE (100 mg/kg i.p.), with or without cotreatment with either flumazenil (FMZ; 5 mg/kg i.p.), ESM (150 mg/kg i.p.) or diazepam (DPZ; 0.5 mg/kg i.p.).  WKE administration significantly increased the PTZ dose needed to induce the first myoclonic jerk (13.09 ± 1.29 vs. 49.71 ± 12.03 mg/kg; p < 0.001), decreased the severity of seizure grades and reduced the mortality rate to 0%. FMZ did not significantly reduce the anticonvulsant effect of WKE. The combination of DPZ and WKE showed a synergic anticonvulsant effect, whereas ESM had no significant influence (p > 0.05) on the WKE effects.  These findings indicated that WKE was effective at reducing seizure severity, at increasing the dose to the first myoclonic jerk and highly efficacious at preventing mortality, because 100% of animals were protected. It seems that this positive effect could apply through signaling pathways other than benzodiazepine-mediated γ-aminobutyric acid receptors and may at least in part be similar to ESM.

Field of study: Medicine
Biotite and muscovite 40Ar–39Ar geochronological constraints on the post-Svecofennian tectonothermal evolution, Forsmark site, central Sweden

In order to characterize the post-Svecofennian tectonothermal evolution of the Fennoscandian Shield, 40Ar–39Ar biotite and some 40Ar–39Ar muscovite geochronological data are reported from a total of 30 surface outcrop and 1,000 m long borehole samples at Forsmark, central Sweden. The 13 surface samples were collected across 3 branches of a major WNW to NW trending system of deformation zones, whereas the boreholes were drilled within a tectonic lens, in between two of these zones. The 40Ar–39Ar biotite ages indicate that the present erosion surface, in central Sweden, cooled below c. 300°C at 1.73–1.66 Ga, and that the rocks could have accommodated strain in a brittle manner between 1.8 and 1.7 Ga. The variation in surface ages is suggested to be due to fault along the large WNW to NW trending deformation zones, following the establishment of a sub-Cambrian peneplain. The minor variation of ages within a single crustal block may be due to disturbance along ENE to NNE trending fracture zones. Possible cooling paths, derived from 40Ar–39Ar hornblende, muscovite and biotite ages, were calculated for the time interval from 1.80 to 1.67 Ga, when the area cooled from c. 500 to 300°C. Cooling rates of 1.9–4°C/m.y. have been attained. Between 1.68 and 1.64 Ga, uplift rates of c. 22 m/m.y. were calculated from borehole 40Ar–39Ar biotite data. Tectonothermal histories, inferred from the combined cooling and uplift rates, are related to simple cooling after the Svecofennian orogeny, to crustal movement in response to far-field effects of c. 1.7 Ga orogenic activities further to the west or to a combination of these possibilities.

Field of study: Environmental science
The use of multiple oxygen implants for fabrication of bipolar silicon-on-insulator integrated circuits

A description is given of the radiation improvements obtained by fabricating bipolar integrated circuits on oxygen-implanted silicon-on-insulator substrates that were manufactured with multiple (low-dose) implants. Bipolar 74ALS00 gates fabricated on these substrates showed an improvement in total dose and dose-rate radiation response over identical circuits fabricated in bulk silicon. Defects in SIMOX material were reduced by over four orders of magnitude. The results demonstrate that bipolar devices, fabricated on multiple-implant SIMOX substrates, can compete with conventional dielectric isolation for many radiation-hardened system applications.

Field of study: Physics
Research on Adjustable Autonomy of Unmanned System

The research and development of Unmanned System′s autonomy is the hot topic in the field of intelligent system.The object of the study is to enable the system to collaborate with operators and to achieve the assigned task,while the system has a certain degree of autonomy.The research and application of Autonomy is summarized in this paper which include autonomy definitions,autonomy levels measurements,adjustable autonomy definitions,frameworks of autonomy and adjustable autonomy.Finally,some challenging research trends are proposed as a future work.

Field of study: Computer science
Preparation of protoplast from Paecilomyces tenuipes,the anamorph of Cordyceps takaomontana

The optimum condition for protoplast preparation of Paecilomyces tenuipes RCEF3456 was investigated by studying some factors,such as mycelium age,kinds of enzymes and its concentration and enzymolysis time.The results showed that protoplasts were obtained for higher production(8.0×107/mL) under the conditions as follows:the hyphae cultured for 18 h,digested by the compound enzyme solution consisting of 1% Lywallzyme,1% Cellulase "Onozuka"R-10 and 1% snailase for 2.5 h at 30℃.Meanwhile,formation and regeneration of protoplasts were observed,and regeneration rate was 1.2%.

Field of study: Agricultural and Food sciences
Impact of vitamin D status and obesity on C-reactive protein in kidney-transplant patients.

We examined whether vitamin D status and obesity are associated with low-grade systemic inflammation, as assessed by serum concentrations of C-reactive protein (CRP) in an adult population of kidney-transplant patients.



This was a single-center, cross-sectional study.



Data were collected between December 2005 and April 2006 from 161 adult (aged >18 years) kidney-transplant patients (mean age, 53.1 years; SD, 11.5 years; females/males, 78/83), with a median kidney-graft age of 7.0 years and serum CRP levels < or =10 mg/L.



Vitamin D status was assessed by serum concentrations of 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D (1,25(OH)(2)D). The presence of low-grade systemic inflammation was assessed by serum CRP. Selected lifestyle factors and anthropometric variables were determined in a subgroup of patients (n = 90). Bivariate correlation and multiple regression analyses were performed.



Hypovitaminosis D (ie, S-25-OHD < or =75 nmol/L) was present in 73% of females, and 89% of males. The median level of serum CRP was 1.7 mg/L. Vitamin D status was not significantly associated with serum CRP. In the patient subgroup, indices of obesity (body mass index, body weight, and fat mass) correlated positively, and lean body mass correlated negatively, with serum CRP. Only fat mass remained significantly associated with serum CRP in multiple regression analysis.



No impact of vitamin D status on low-grade systemic inflammation was found. Fat mass correlated positively with CRP, suggesting that obesity may increase the risk of cardiovascular disease and chronic allograft rejection in kidney-transplant patients.

Field of study: Medicine
Admissible Designs for Polynomial Spline Regression

Given f = (f sub o,...,f sub m) on the closed interval a,b we consider the matrix M(mu) = integral (f'f d mu) for any probability measure mu on the closed interval a,b. The measure mu is called admissible if there does not exist a nu such that M(nu) - M(mu) is positive semi-definite and not equal to 0. A theorem is given.

Field of study: Mathematics
Three-dimensional modeling and experimental validation of air-breathing PEM fuel cell

The air-breathing proton exchange membrane fuel cells (PEMFCs) are one of the most competitive candidates for future portable-power applications. To predict the performance of air-breathing PEMFCs and promote its commercialization, a three-dimensional mathematical model was developed,including full governing equations for fluid dynamics, electrode kinetics, and water transport in membrane. The model was numerically solved with commercial CFD tool STAR-CD and user-defined subroutine in FORTRAN code using the finite-difference technique. According to the numerical results, the experiment system was designed. The performance of an air-breathing PEMFC and temperature distribution on the surface of diffusion layer was tested. The calculated cell performance curve was in good agreement with experimental results.It was demonstrated that the oxygen mass transfer rate by natural convection played a major role in cell performance and the interaction of velocity, temperature, current density, water concentration. The model could be used as a computer-aided design tool for an air-breathing PEMFC to obtain better cell performance.

Field of study: Chemistry, Environmental science
Growth parameter investigation of Al0.25Ga0.75N/GaN/AlN heterostructures with Hall effect measurements

Hall effect measurements on unintentionally doped Al0.25Ga0.75N/GaN/AlN heterostructures grown by metal organic chemical vapor deposition (MOCVD) were carried out as a function of temperature (20–300 K) and magnetic field (0–1.4 T). Magnetic-field-dependent Hall data are analyzed using the quantitative mobility spectrum analysis (QMSA) technique. The QMSA technique successfully separated electrons in the 2D electron gas (2DEG) at the Al0.25Ga0.75N/GaN interface from other 2D and 3D conduction mechanisms of the samples. 2DEG mobilities, carrier densities and conductivities of the investigated samples are compared at room temperature and low temperature (20 K). For a detailed investigation of the 2DEG-related growth parameters, the scattering analyses of the extracted 2DEG were carried out for all of the samples. Using the results of the scattering analyses, the relation between the growth and scattering parameters was investigated. Increments in the interface roughness (IFR) are reported with the increased GaN buffer growth temperatures. In addition, a linear relation between the deformation potential and interface roughness (IFR) scattering is pointed out for the investigated samples, which may lead to a better understanding of the mechanism of IFR scattering.

Field of study: Materials science
Acoustooptic nonreciprocal phase element

A calculation is made of the characteristics of an acoustooptic nonreciprocal phase element based on an AOM-1 light-intensity modulator. The method of coupled waves is used to find the dependences of the phase shift between the opposite light beams on the deviation of the angular position of the element from the Bragg angle, and also on the ultrasonic wave power.

Field of study: Engineering, Physics
Determination of Acrylamide in fried food of potato and foreign snack by Gas chromatography/Mass spectrometry

This Article used pre-processing method from Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention. Acrylamide in eight kinds fried food of potato and foreign snack were determinated by Gas chromatography and Quadrupol Mass spectrometry. According to the relative time and abundance of homologize monitoring ion in Acrylamide, we analyzed its quality. The results show that the RSD of relative response factor(RRF) is less than 20%. It was fit for the require of internal standard method. Acrylamide content in fried food of potato and foreign snack were 456～5269μg/kg and 147～214μg/kg respectively.

Field of study: Agricultural and Food sciences
U-Pb geochronology of the Nain craton on the eastern margin of the Torngat Orogen, Labrador

New U–Pb geochronological results provide insight into the geological evolution of the northernmost Nain craton. A tonalitic orthogneiss, retrogressed from granulite to amphibolite facies, is interpreted to have crystallized at 2832 ± 3 Ma; zircon overgrowths, dated at 2769 ± 5 Ma, are interpreted as metamorphic in origin, whereas metamorphic monazite crystallized at 2692 ± 2 Ma. The crystallization age of this sample suggests it may be correlative with similar rocks of the Kanairiktok Plutonic Suite of the Hopedale block, whereas the age of the zircon overgrowths is synchronous with metamorphism in the Saglek block and may indicate a link at this time. A foliated tonalite crystallized at 2802 ± 2 Ma; titanite in this sample records deformation at 1745 ± 4 Ma; the emplacement age suggests a link with Hopedale block, whereas the titanite growth is clearly related to Torngat orogeny. Two foliated granites crystallized at 2587 ± 3 and 2564 ± 2 Ma, respectively, synchronous with late magmatic events recognize...

Field of study: Environmental science
The Therapeutic Factors of Group-Analytical Treatment

The therapeutic factors in two sexually mixed groups of 7 members each have been examined.

It was found that certain field forces may have a generally beneficial effect, such as the common transference to the therapist, the group task of candid self-revelation, the emotional and intellectual responses to interpretations, and the sexual composition of the group.

Other group influences had a differential therapeutic effect. Among these the general verbal group task was of particular importance. Laliophobic patients who were unable to comply readily with this task did not respond as favourably to group treatment as other patients.

Of favourable prognosis was the ability to form positive identifications with the group, to be more disturbed by sexual topics of discussion than by other group events, and the attainment of a high degree of group popularity.

Group popularity was distinguished from direct popularity. The latter was based on the desires for private friendship which patients felt for each other. It had no reference to group performance, and had no effect on the therapeutic outcome.

The degree of dominance which patients gained in the group had no influence on their improvements.

Field of study: Medicine, Psychology