nils-herrmann/clean_scirepeval huggingface dataset:
Current expansion of high-power diode laser bars

980 nm GaAs/AlGaAs separate confinement hetero-structure single quantum well laser bars were grown by metal organic chemical vapor deposition. The relationships between the etching depth and the bars’ parameters have been studied. When the bar is not etched deep to the active layer, the output power and the slope efficiency are in direct proportion to the etching depth, while the threshold current are in inverse proportion to the etching depth. When the bar is etched deeper than the active layer, the output power and the slope efficiency become lower and the threshold current become higher. The best etching depth is 1.993 mm in the experiment, which is less than the depth of the active layer.

Field of study: Physics
Detecting Malicious Web Servers with Honeyclients

Using malicious sites to launch attacks against client user applications is a growing threat in recent years. This led to emergence of new technologies to counter and detect attacks against end user. One of these technologies is honeyclient (aka client honeypot). Honeyclients crawl the Internet to find and identify web servers that exploit client-side vulnerabilities. In this paper, we address honeyclients by studying and analyzing low - interaction and high-interaction honeyclients. We introduce a comparison attributes to evaluate honeyclients by comparing between the two types . Moreover, we present techniques can be used by malicious websites to evade and fingerprint honeyclients, and we make recommendations to overcome these evasion techniques. By analyzing characteristics of honeyclients, we introduce factors to define and measure honeyclients effectiveness. Using malicious sites to launch attacks against client user applications is a growing threat in recent years. This led to emergence of new technologies to counter and detect attacks against end user. One of these technologies is honeyclient (aka client honeypot). Honeyclients crawl the Internet to find and identify web servers that exploit client-side vulnerabilities. In this paper, we address honeyclients by studying and analyzing low-interaction and high-interaction honeyclients. We introduce a comparison attributes to evaluate honeyclients by comparing between the two types. Moreover, we present techniques can be used by malicious websites to evade and fingerprint honeyclients, and we make recommendations to overcome these evasion techniques. By analyzing characteristics of honeyclients, we introduce factors to define and measure honeyclients effectiveness.

Field of study: Computer science
Coherent optical production of the Hough transform.

The Hough transform (HT) is an efficient shape detector that maps straight lines into a two-parameter feature space. Recently it has been pointed out that the forward Radon transform (FRT), well known from the theory of computed tomography, and the HT are equivalent for binary images. In this paper, analog coherent optical implementation of the FRT is discussed. The FRT will not only be of use in implementing the HT shape descriptors but also act as a coherent optical preprocessor for the implementation of multidimensional convolution, correlation, and spectral analysis using 1-D acoustooptical signal processing devices. Several different coherent optical FRT architectures are presented. Experimental results using conventional coherent Fourier transform configuration are given. The relationship between the coherent optical implementation of the FRT and the inverse Radon transform, an important tool in computed tomography, is also detailed.

Field of study: Physics
Sum-Rate Maximization in Two-Way AF MIMO Relaying: Polynomial Time Solutions to a Class of DC Programming Problems

Sum-rate maximization in two-way amplify-and-forward (AF) multiple-input multiple-output (MIMO) relaying belongs to the class of difference-of-convex functions (DC) programming problems. DC programming problems occur also in other signal processing applications and are typically solved using different modifications of the branch-and-bound method which, however, does not have any polynomial time complexity guarantees. In this paper, we develop two efficient polynomial time algorithms for the sum-rate maximization in two-way AF MIMO relaying. The first algorithm guarantees to find at least a Karush-Kuhn-Tucker (KKT) solution. There is a strong evidence, however, that such a solution is actually globally optimal. The second algorithm that is based on the generalized eigenvectors shows the same performance as the first one with reduced computational complexity. The objective function of the problem is represented as a product of quadratic fractional ratios and parameterized so that its convex part (versus the concave part) contains only one (or two) optimization variables. One of the algorithms is called POlynomial Time DC (POTDC) and is based on semi-definite programming (SDP) relaxation, linearization, and an iterative Newton-type search over a single parameter. The other algorithm is called RAte-maximization via Generalized EigenvectorS (RAGES) and is based on the generalized eigenvectors method and an iterative search over two (or one, in its approximate version) optimization variables. We derive an upper-bound for the optimal value of the corresponding optimization problem and show by simulations that this upper-bound is achieved by both algorithms. It provides an evidence that the algorithms find a global optimum. The proposed methods are also superior to other state-of-the-art algorithms.

Field of study: Engineering
Apotheosis, not apocalypse: methods in protein crystallography.

Outstation, c/o DESY, Notkestrasse 85, 22603 Hamburg, Germany, European Molecular Biology Laboratory, Grenoble Outstation, c/o ILL, BP 156, 6 Rue Jules Horowitz, 38043 Grenoble CEDEX 9, France, MRC Laboratory for Molecular Biology, Hills Road, Cambridge, England, Biology Department, Brookhaven National Laboratory, Upton NY 11973-5000, USA, and Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100,

Field of study: Chemistry
Late Pleistocene and Holocene palaeohydrology of Lake Rukwa, Tanzania, inferred from diatom analysis

Diatom analysis has been used to provide information on the lake-level fluctuations of Lake Rukwa during the last 21.7 ka. Diatom-inferred chemical variables (conductivity, pH, anion and cation ratios) indicate that at the LGM lake level was low, probably driven by a low P:E ratio, but with sufficient water to avoid desiccation. Following the LGM, deep water conditions were obtained through a series of steps until maximum water depth was reached by at least 13.5 ka. The high lake-level phase lasted through the Early Holocene until after 6.7 ka. A shallow saline lake has occupied the basin from ca. 5.5 ka until the present day. The pattern of reconstructed lake-level fluctuation in Lake Rukwa is similar to that from Lake Tanganyika and other lakes from the equatorial and northern tropical zone. We can confirm that the N-tropical mode of millennial scale lake-level change since the LGM extended to at least 8°S.

Field of study: Environmental science, Geography
Experience in using xeomin in the treatment of arm and hand spasticity in the early rehabilitation phase of stroke

To reduce arm and hand spasticity, 28 patients in the early rehabilitation phase of ischemic hemisphere stroke received injections of the botulinum toxin A preparation xeomin in the content of complex rehabilitation programs. The following muscles: m. biceps brachii, m. flexor digitorum profundus, m. flexor digitorum superficialis, m. flexor carpi ulnaris, m. flexor carpi radialis were injected according to standard scheme. The total dose of drug was 200U in moderate (2-3 scores on the Ashworth scale) and 300U in marked (3-4 scores on the Ashworth scale) spasticity. Efficacy and safety of treatment was assessed at baseline and 2, 4, 8, 12, 16 weeks after injections. Xeomin significantly (p<0.05) reduced muscle tonus in patients with post-stroke spasticity of different severity. Clinical effect was seen 2 weeks after injection, it reached maximum at week 4 and then slowly decreased to week 16. The improved functional activity of the paretic arm (due to patient's and caregiver's reports) remained for to 12 weeks. The treatment was most effective in the group of patients with moderate spasticity. The correlation analysis confirmed that the severity of spasticity increased with the disease duration that reduced rehabilitation efficiency. The treatment with xeomin was safe, no serious side-effects were found.

Field of study: Medicine, Psychology
Structural performance of steel fibre reinforced concrete — Part III. Behaviour in tension

The present paper of a series deals with the experimental characterisation of tensile splitting strength and compressive behaviour of different structural concrete containing different volume of steel fibre reinforcement (0 V%, 0.5 V%, 1.0 V%, 75 kg/m3, 150 kg/m3) and different configuration of steel fibres (crimped, hooked-end). Tensile splitting tests were carried out on standard cylinder (∅ = 150 mm, l = 300 mm) specimens (so-called Brazilian test) considering random fibre orientation. Since the fibre orientation may significantly affect the tensile behaviour test series were also performed on cross-section (100 mm × 100 mm) of steel fibre reinforced concrete beams (100 mm × 100 mm × 240 mm) sawn out of steel fibre reinforced slab elements. Taken as a whole behaviour of steel fibre reinforced concrete was examined in tension taking into consideration different experimental parameters such as fibre content, type of fibres, fibre configuration, fibre orientation, size of specimens (size effect) and concr...

Field of study: Engineering
The Doctor of Arts: A Decade of Development, 1967-77.

Although the Doctor of Arts (D. A.) degree had been discussed as early as the 1940s as possible teaching-related alternative to the research-oriented Ph.D., the first D.A. program (including mathematics, history, English, and the fine arts) was initiated at Carnegie-Mellon University in the fall of 1967. Carnegie-Mellon conferred the first D.A. degree (mathematics) in 1968 and three (history) in 1969. The best data on the spread of the D.A. have been provided by Robert Koenker, dean of the graduate school at Ball State University. Koenker's first survey (March 1970) reported that three universities were offering the degree and that twenty-five to thirty others were planning to introduce the degree within a year or two. By January 1971, Koenker found seven universities offering the D.A. in biology, economics, English, fine arts, history, mathematics, foreign languages, music, physical education, and political science. By November 1971 he reported sixteen universities offering at least one D.A. program. The fields of study had expanded to include chemistry and additional foreign languages. The accuracy of these data obviously depends upon the response of institutions and the care exercised in providing them. Dressel  found that, as of spring 1973, the D.A. degree-granting institutions were twenty-one in number, offering the degree in a total of forty-four departments and eighteen fields. The fields included art (1 program), biology (4), business and economics (1), chemistry (4), creative writing (1 since discontinued), English (10), French (1), German (1),

Field of study: Education
Electronic control of heat flow across graphene interfaces

We experimentally demonstrate fast control of heat conduction using electrostatic fields. Heat flow modulation is achieved through gate control perpendicular to the channel of top-gated graphene field-effect transistors (GFETs), and is monitored by a newly developed technique, voltage-modulated thermoreflectance (VMTR). We find that the thermal conductance of SiO2/graphene/SiO2 interfaces increases by up to {\Delta}G~0.8 MWm-2K-1 under electrostatic fields of <0.2 Vnm-1. We propose two possible explanations for the observed {\Delta}G. First, since the applied electrostatic field induces charge carriers in graphene, our VMTR measurements could originate from heat transfer between the induced charge carriers and surface polar phonons in SiO2 via remote interfacial phonon (RIP) scattering. Second, the increase in heat conduction could be engendered by better conformity of graphene interfaces under electrostatic pressure exerted by the induced charge carriers. Regardless of the origins of the observed {\Delta}G, our VMTR measurements establish an upper limit for heat transfer from unbiased graphene to SiO2 substrates via RIP scattering for the graphene-SiO2 interface; i.e., only <2 % of the interfacial heat transport is facilitated by RIP scattering even at a carrier concentration of ~4x10^12 cm-2. Our findings also inaugurate a new mechanism to control and modulate heat transport, which could facilitate realization of phononic devices.

Field of study: Physics
IMRT delivery verification using a spiral phantom.

In this paper we report on the testing and verification of a system for IMRT delivery quality assurance that uses a cylindrical solid water phantom with a spiral trajectory for radiographic film placement. This spiral film technique provides more complete dosimetric verification of the entire IMRT treatment than perpendicular film methods, since it samples a three-dimensional dose subspace rather than using measurements at only one or two depths. As an example, the complete analysis of the predicted and measured spiral films is described for an intracranial IMRT treatment case. The results of this analysis are compared to those of a single field perpendicular film technique that is typically used for IMRT QA. The comparison demonstrates that both methods result in a dosimetric error within a clinical tolerance of 5%, however the spiral phantom QA technique provides a more complete dosimetric verification while being less time consuming. To independently verify the dosimetry obtained with the spiral film, the same IMRT treatment was delivered to a similar phantom in which LiF thermoluminescent dosimeters were arranged along the spiral trajectory. The maximum difference between the predicted and measured TLD data for the 1.8 Gy fraction was 0.06 Gy for a TLD located in a high dose gradient region. This further validates the ability of the spiral phantom QA process to accurately verify delivery of an IMRT plan.

Field of study: Medicine, Physics
Tandem C–C Bond Cleavage of ­Cyclopropanols and Oxidative Aromatization by Manganese(IV) Oxide in a Direct C–H to C–C Functionalization of Heteroaromatics

We report a direct C–H to C–C bond functionalization of electron-deficient heteroaromatics enabled by mild C–C bond cleavage of cyclopropanols as a new route to β-aryl carbonyl-containing products. Additionally, as an alternative to using a “catalyst” that requires an excess amount of a sacrificial oxidant for regeneration and/or oxidative aromatization, this paper features manganese(IV) oxide as an inexpensive “dual role” reagent – effecting both C–C bond cleavage and ultimate rearomatization. Under the specified conditions, a variety of heterocycles proved competent for regioselective C–C bond formation, alongside a diverse array of cyclopropanols with broad functional-group tolerance. We highlight applications to complex-molecule synthesis and direct derivatization of biologically active alkaloids. Furthermore, kinetic isotope effect (KIE) experiments, radical scavengers, and some insight into the application of tri- and tetravalent manganese species are invoked to shape an initial mechanistic hypothesis.

Field of study: Chemistry
Stereotype Threat Effects on African American Children in an Urban Elementary School

This study investigated whether a diagnostic testing condition leads to stereotype threat effects for African American children (n = 198) at an urban elementary school. Results indicated that presenting a reading test as diagnostic of abilities hindered the performance of African American children aware of racial stereotypes but not of those unaware of such stereotypes. For stereotype-aware children, the effect of stereotype threat on performance was moderated by level of domain identification such that the effects were most pronounced among children placing greater value on achievement. In addition, domain identification contributed to greater anxiety and lower self-efficacy, suggesting that it is a primary vulnerability factor for stereotype threat effects. Implications for educational equity are discussed, as well as suggestions for developing interventions capable of attenuating stereotype threat effects among children.

Field of study: Education
Atherogenic cytokines and chemokines in chronic hepatitis C are not associated with the presence of cardiovascular diseases

HighlightsChronic hepatitis C was associated with insulin resistance without diabetes.The production of GDF‐15 was elevated in CHC patients.Increased production of atherogenic cytokines was observed in PBMC.No increase in atherogenic risk indexes and frequency of prior myocardial infarction. &NA; There appears to be an associative link between chronic hepatitis C (CHC) and cardiovascular diseases (CVDs). However, the exact nature of the relationship between CHC and CVDs has not been elucidated. We investigated the presence of CVDs and the clinical and laboratory alterations associated with these diseases in CHC patients. Twenty‐six CHC patients, 35 individuals with atherosclerosis (Athero) and 27 healthy individuals were examined for risk factors for CVD, lipid profile, atherogenic risk indexes, and insulin resistance (IR). Cardiac biomarkers and the chemokines and cytokines involved in atherosclerosis were also evaluated. A higher prevalence of prior acute myocardial infarction was found in the Athero group. Most CHC patients were infected with the hepatitis C virus genotype 1 and exhibited either no hepatic fibrosis or a mild to moderate liver fibrosis. The apolipoprotein B/apolipoprotein A‐I and triglyceride/high‐density lipoprotein cholesterol ratios and C‐reactive protein levels were lower in CHC patients than in the Athero group. Further, IR was elevated in the CHC group and associated with the waist circumference. High GDF‐15 levels were observed in the CHC group, which were inversely correlated with APOB levels. Peripheral blood mononuclear cells from CHC patients produced more IFN‐&ggr;, TNF‐&agr; and IL‐6 than CAD PBMC but the production of IL‐10 and IL‐1&bgr; was similar. CHC and CAD groups presented similar levels of IL‐8, MCP‐1 and LAP‐TGF‐&bgr;1. Increased IR, elevated levels of GDF‐15, and high production of atherogenic cytokines can be observed in Brazilian CHC patients without association with diabetes and clinical manifestation of cardiovascular diseases.

Field of study: Medicine
CARIBBEAN RESEARCH PROJECT: PROGRESS REPORT

Progress is reported in mapping the Eastern Caribbean area; 24 Ph.D. theses have been completed or are under way. One major objective is to interpret the available geophysical data in light of the geologic history of the past 100 million years.

Mapping of a series of quadrangles from Caracas to Tinaco in Venezuela has provided a cross section through the Cordillera de la Costa and Serrania del Interior. Several episodes of mid-Cretaceous metamorphism, rather than a single episode, are now recognized.

The concept that island arcs represent an early stage of alpine-type mountain building is rejected. Alpine-type mountains are developed along the thin margin of continental crust, island arcs on an oceanic type of crust. The two represent different kinds of reaction to the same type of tectonic forces. Germano-type mountains develop similarly in areas of continental crust of normal thickness. All three types can be seen along a single tectonic axis from the Antillean islands (island arc) into the coastal ranges of Venezuela (alpine-type) and thence to the Venezuelan Andes (germano-type).

Laboratory measurements of seismic velocities in fresh peridotite (8.4 km/sec) through partially serpentinized peridotite to serpentinite (5.7 km/sec) indicate that the so-called basaltic crust of the oceans may be peridotite two-thirds serpentinized. If so, Mattson's basement rocks which are serpentinites may be altered mantle rocks exposed at the surface. On the other hand MacKenzie has shown that true intrusive peridotites emplaced at temperatures above a minimum of 800°C. exist.

Field of study: Geology
Evaluation of compatibility of thick-film PTC thermistors and LTCC structures

The electrical and microstructural characteristics of 1 kΩ/sq. thick-film thermistors with high positive temperature coefficients of resistivity, i.e. PTC 5093 (Du Pont) fired either on “green” LTCC (low temperature cofired ceramics) substrates or buried within LTCC structures, were evaluated. The active phase (ruthenium oxide) in the PTC thermistors is not present in the dried films but is formed during firing due to the decomposition of the ruthenate phase. Because of interactions between a glassy LTCC material and thermistors electrical characteristic, i.e. sheet resistivities and noise indices of thermistors fired on the surface LTCC substrates, changed from values obtained on alumina substrates. The differences in the measured electrical parameters were attributed to the interactions between the thermistor layers and the glassy LTCC substrates. The inter-diffusion of oxides, mainly PbO and Al 2 O 3 , was confirmed by microanalysis. In the case of buried thermistors, presumably due to the incompatibility of both materials, the structure de-laminated during firing. Cracks between the buried PTC films and the LTCC substrates as well as cracks in PTC films resulted in high sheet resistivities and high noise indices.

Field of study: Engineering
Therapeutic effect of combined treatment with CD suicide gene and GM CSF gene on murine melanoma and its immunological mechanism

To observe the therapeutic effect of adenovirus expressing cytosine deaminase (AdCD) in combination with adenovirus expressing GM CSF (AdGMCSF) followed by administration of a kind of prodrug, 5 fluorocytosine (5FC) on melanoma in mice.  Melanoma bearing mice were administered with AdCD/5FC/AdGMCSF, AdCD/5FC, AdGM CSF, control adenovirus AdlacZ/5FC, or PBS.  The results demonstrated that significant growth inhibition of established tumors and prolongation of survival period were observed in tumor bearing mice after AdCD/5FC/AdGMCSF combined therapy when compared with mice treated with AdCD/5FC, AdGM CSF, AdlacZ/5FC, or PBS ( P 0.01). The activity of cytotoxic T lymphocytes could be induced significantly after the combined therapy. The expression of MHC I and B7 1 molecules on freshly isolated tumor cells after combined therapy increased greatly, and more dendritic cells and CD8 + T cells infiltrated into the tumor mass when measured with FACS.  Our results suggest that combined therapy with suicide gene and GM CSF gene transfer could directly eradicate established tumors and efficiently induce the antitumor immunity of the mice.

Field of study: Biology
Approximation formulae for compound poisson processes for a kind of claim distributions having a prescribed asymptotic behavior

The present contribution deals with an approximation for the compound Poisson process for large values of the operational time. Two cases are dealt with, according to the existence of the third or second moment of the individual claim distribution. The special feature of this claim distribution is its behavior for large values, i.e., f"Y(y) ~ a"0y + a"1y^2 + ... + a"ky^k + ..., (y -> ~). In these cases, an Edgeworth-like approximation is given.

Field of study: Mathematics