nils-herrmann/clean_scirepeval huggingface dataset:
Design of dual-mode conical horn feed with equal E and H patterns

This paper presents a high power feed system for 7.3 m Cassegrain antenna. In order to make E and H patterns of the feed equal in the illuminated area, the dual-mode conical horn is chosen as the feed form. Since the high power signal is transmitted from the BJ-32 waveguide, a mode convertor from rectangular TE_(10) mode to circular TE_(11) mode in the feed system should be provided. The feed system, including a dual-mode conical horn and a mode convertor, was designed, manufactured, and measured. The measured results indicate that the feed system achieves the design goal, and the measured results agree well with the theoretical results.

Field of study: Physics
Early NMDA receptor blockade impairs defensive behavior and increases cell proliferation in the dentate gyrus of developing rats.

These studies were conducted to determine whether (a) early N-methyl-D-aspartate (NMDA) receptor blockade impairs defensive behavior and (b) a relationship exists between defensive behavior and the production of granule cells in the dentate gyrus. Rat pups were treated with different doses of the NMDA receptor antagonist CGP 43487 on postnatal day (P) 5, and their behavior was observed following exposure to an unfamiliar adult male rat, a potential predator, on P13, P20, and P30. A dose-dependent impairment in freezing behavior was observed in rat pups treated with NMDA receptor antagonist on P13, P20, but not P30. Moreover, a dose-dependent increase in the number of (3)H-thymidine-labeled cells in the dentate gyrus was detected following CGP 43487 treatment, suggesting that an inverse relationship exists between cell proliferation and freezing behavior in rat pups following NMDA receptor blockade.

Field of study: Biology, Psychology
SYNTHESIS OF ( S )-PROLINE DERIVATIVES WITH AN ALKYLATED N-BENZYL SUBSTITUENT. BENZYLATION OF ( S )-INDOLINE-2-CARBOXYLIC ACID

The synthesis is reported of (S)-proline derivatives which contain a 2,4,6-trimethyl-, 4-tert-butyl-, or pentamethylbenzyl substituent on the nitrogen atom. Under similar conditions the benzylation of indoline-2-carboxylic acid was unsuccessful. Treatment of indoline-2-carboxylic acid with benzyl chloride in the presence of KOH in dimethylacetamide gave the benzyl ester of N-benzylindoline-2-carboxylic acid which is unstable on light.  A. N. Popkov. English Translation in Chemistry of Heterocyclic Compounds , 2000, 36 (5), pp 544-547

Field of study: Chemistry
Experimental Studies on Slat Noise Reduction

As the noise pollution of aircraft is becoming more and more serious, the airworthiness standard puts more and more strict requirements on the aerodynamic noise level of civil passenger aircraft. The slat noise is the main source of noise during the small angle of attack during the takeoff and landing phases. In this paper, for the aerodynamic noise problem of high-lift airfoil slats, a three-segment wing lifting device model is taken as an experimental model, and the aeroacoustic wind tunnel test is carried out. In order to avoid the influence of flap noise, the slat is fully unfolded and the flap is retracted. The acoustic mechanism of the aerodynamic noise of the slat is studied. Then the aerodynamic noise of the deformed slat is studied. The noise reduction effect and aerodynamic performance of the deformable slat are studied by comparing the reference position with the deformed slat. Finally, the related noise reduction mechanism is discussed.

Field of study: Engineering
Straw into Gold: Lessons Learned (and Still Being Learned) at the Manitoba Centre for Health Policy.

What lessons have we learned at the Manitoba Centre for Health Policy (MCHP) about knowledge translation (KT) over the past 20 years, and what is our vision for the future? How does that KT interrelate with our other activities - research and the Population Health Data Repository? Who first noticed that "there's gold in them thar hills," and what did they do about it? How did we weave administrative database "straw" into gold, how have we panned for gold and how do we look for the pot of gold in the future? This paper describes how MCHP began with an integrated KT research relationship with government, and through The Need to Know Team, extended KT to regional health authority planners. It describes the various push-pull KT mechanisms that MCHP has used, including dissemination of research to planners through interactive workshops, and to other researchers through Web-based resources.

Field of study: Medicine, Political science
The Design and Development of Individualized Curriculum Materials for Higher Education

This paper describes a self-instructional curriculum design and development course, based on a process model for individualizing instruction, suited to the complex subject matter of higher education. The course is designed to train educational research and development personnel, teachers, administrators, and industrial training specialists in the design of instructional materials. Features of the model which make it appropriate for higher education are its emphasis on the structure of the discipline, sampling of high level intellectual skills, procedures for systematic application of research-based instructional strategies to instructional design, and incorporation of independent inquiry into a structured model.

Field of study: Education
Diode Laser Assisted Filament Winding of Thermoplastic Matrix Composites

A new consolidation method for the laser-assisted filament winding of thermoplastic prepregs is discussed: for the first time a diode laser is used, as well as long glass fiber reinforced polypropylene prepregs. A consolidation apparatus was built by means of a CNC motion table, a stepper motor and a simple tensioner. Preliminary tests were performed in a hoop winding configuration: only the winding speed was changed, and all the other process parameters (laser power, distance from the laser focus, consolidation force) were kept constant. Small wound rings with an internal diameter of 25 mm were produced and compression tests were carried out to evaluate the composite agglomeration in dependence of the winding speed. At lower winding speeds, a strong interpenetration of adjacent layers was observed.

Field of study: Materials science
Dynamic CPU provisioning for self-managed secure web applications in SMP hosting platforms

Overload control mechanisms such as admission control and connection differentiation have proven effective for preventing overload of application servers running secure web applications. However, achieving optimal results in overload prevention is only possible when some kind of resource management is considered in addition to these mechanisms. In this paper we propose an overload control strategy for secure web applications that brings together dynamic provisioning of platform resources and admission control based on secure socket layer (SSL) connection differentiation. Dynamic provisioning enables additional resources to be allocated to an application on demand to handle workload increases, while the admission control mechanism avoids the server's performance degradation by dynamically limiting the number of new SSL connections accepted and preferentially serving resumed SSL connections (to maximize performance on session-based environments) while additional resources are being provisioned. Our evaluation demonstrates the benefit of our proposal for efficiently managing the resources and preventing server overload on a 4-way multiprocessor Linux hosting platform, especially when the hosting platform is fully overloaded.

Field of study: Computer science
Photosynthetic activity and population dynamics of Amoebobacter purpureus in a meromictic saline lake

A dense population of the purple sulfur bacterium Amoebobacter purpureus in the chemocline of meromictic Mahoney Lake (British Columbia, Canada) underwent consistent changes in biomass over a two year study period. The integrated amount of bacteriochlorophyll reached maxima in August and declined markedly during early fall. Bacteriochlorophyll was only weakly correlated with the light intensity and water temperature in the chemocline. In the summer, bacterial photosynthesis was limited by sulfide availability. During this period the intracellular sulfur concentration of A. purpureus cells decreased. A minimum concentration was measured at the top of the bacterial layer in August, when specific photosynthetic rates of A. purpureus indicated that only 14% of the cells were photosynthetically active. With the exception of a time period between August and September, the specific growth rates calculated from CO2 fixation rates of A. purpureus were similar to growth rates calculated from actual biomass changes in the bacterial layer. Between August and September 86% of the A. purpureus biomass disappeared from the chemocline and were deposited on the littoral sediment of Mahoney Lake or degraded within the mixolimnion. This rise of cells to the lake surface was not mediated by an increase in the specific gas vesicle content which remained constant between April and November. The upwelling phenomenon was related to the low sulfur content of A. purpureus cells and a low resistance of surface water layers against vertical mixing by wind.

Field of study: Biology, Environmental science
Transferrin glycans: a possible link between alcoholism and hepatic siderosis.

The hepatic uptake of 59Fe from diferric rat and rabbit asialotransferrins and from human transferrin lacking two sialyl residues was investigated in rats in experiments lasting for 1 hr. The 59Fe attached to either of these preparations disappeared from the plasma more rapidly than the 59Fe introduced with the unmodified respective parent proteins. Most of the 59Fe activity that had disappeared from the circulation could be recovered with the liver. Studies with double-labeled (125I, 59Fe) preparations showed that the enhanced 59Fe clearance was not associated with increased catabolism of the modified transferrins. Prolonged, heavy alcohol consumption, as shown by others, results in the appearance of sialic acid-deficient transferrin (two residues missing) in human serum. We suggest that the increased capacity of transferrin deficient in sialic acid to selectively deposit iron in the hepatocyte may be of significance for the development of the hepatic siderosis observed in alcoholism.

Field of study: Medicine
Thermal emission of InAs induced by band tails

The band tail effect on the thermal emission (TE) integrated power and the spectral distribution ( lambda =3-5 mu m) in n-InAs (Nd-Na=1.6*1016 cm-3) has been investigated for the first time. The Urbach parameter Teff has been determined in the temperature range 310-400 K. Some practical uses for the results obtained are also discussed.

Field of study: Materials science
Freezing and thawing magnetic droplet solitons

Magnetic droplets are non-topological magnetodynamical solitons displaying a wide range of complex dynamic phenomena with potential for microwave signal generation. Bubbles, on the other hand, are internally static cylindrical magnetic domains, stabilized by external fields and magnetostatic interactions. In its original theory, the droplet was described as an imminently collapsing bubble stabilized by spin transfer torque and, in its zero-frequency limit, as equivalent to a bubble. Without nanoscale lateral confinement, pinning, or an external applied field, such a nanobubble is unstable, and should collapse. Here, we show that we can freeze dynamic droplets into static nanobubbles by decreasing the magnetic field. While the bubble has virtually the same resistance as the droplet, all signs of low-frequency microwave noise disappear. The transition is fully reversible and the bubble can be thawed back into a droplet if the magnetic field is increased under current. Whereas the droplet collapses without a sustaining current, the bubble is highly stable and remains intact for days without external drive. Electrical measurements are complemented by direct observation using scanning transmission x-ray microscopy, which corroborates the analysis and confirms that the bubble is stabilized by pinning.

Field of study: Physics
On the conversion between IFPUG and COSMIC software functional size units: A theoretical and empirical study

Since 1984 the International Function Point Users Group (IFPUG) has produced and maintained a set of standards and technical documents about a functional size measurement methods, known as IFPUG, based on Albrecht function points. On the other hand, in 1998, the Common Software Measurement International Consortium (COSMIC) proposed an improved measurement method known as full function points (FFP). Both the IFPUG and the COSMIC methods both measure functional size of software, but produce different results. In this paper, we propose a model to convert functional size measures obtained with the IFPUG method to the corresponding COSMIC measures. We also present the validation of the model using 33 software projects measured with both methods. This approach may be beneficial to companies using both methods or migrating to COSMIC such that past data in IFPUG can be considered for future estimates using COSMIC and as a validation procedure.

Field of study: Computer science, Engineering
Therapeutic use of an anti-ErbB3 monoclonal antibody.

Emerging evidence suggests that the catalytically inactive ErbB3 (HER3) protein plays a fundamental role in normal tyrosine kinase receptor signaling as well as in aberrant functioning of these signaling pathways, resulting in several forms of human cancers and some mental disorders. Here we report the generation of a specific anti-ErbB3 antibody intended for use in diagnosing disease or therapeutic application. By using the hybridoma technique, one cell line (2E(12)C(3)) stably producing anti-ErbB3 antibody was obtained. Its molecular weight was about 185 kDa and its isotype was IgG 2a and κ, respectively. The affinity constant (Kaff) of the anti-ErbB3 MAb was 5.83×10(10) M(-1). This antibody may become a useful tool for diagnostic and therapeutic targeting of ErbB3-expressing cancers or helpful in highlighting the etiology of schizophrenia.

Field of study: Biology
Synthesis and α‐Glucosidase and α‐Amylase Inhibitory Activity Evaluation of Azido‐ and Aminocyclitols

For the synthesis of some azido-and aminocyclitols, (3aRS, 7aSR)-1,3,3a,7a-tetrahydroisobenzofuran was used as the starting material. For further functionalization of the diene unit, the diene was subjected to epoxidation reactions to give mono-and bisepoxides depending on the amount of m-chloroperbenzoic acid used. The ring-opening of the epoxide functionality with NaN3 resulted in the formation of mono- and bisazido cyclitols. The tetrahydrofuran ring was opened in an acid-catalysed reaction with sulfamic acid. The reduction of azide groups to give amines provided various amino-and bisaminocyclitol derivatives. The inhibitory effects of 20 compounds against alpha-glucosidase and alpha-amylase were tested. The results indicated that some of these compounds seem to have good inhibitory activity against alpha-glucosidase, and low inhibitory activity against alpha-amylase. Furthermore, it was demonstrated that the number and position of azides, amines, and hydroxy groups appeared to play an important role in determining the inhibitory potency of these compounds.

Field of study: Chemistry
Detection, identification and phylogenetic analysis of lactic acid bacteria isolated from Tarkhineh, Iranian fermented cereal product, by amplifying the 16s rRNA gene with universal primers and differentiation using rep-PCR

Tarkhineh is a traditional fermented cereal based food which is produced in different rural areas in Kermanshah province, Iran. The aims of this study were to identify the predominant lactic acid bacteria isolates. A total of 75 Gram-positive and catalase-negative isolates were subjected to grouping and identifying using the carbohydrates fermentation profiles and 16S rDNA sequencing, respectively. The sequencing results showed that the majority of the strains belonged to the genus of Lactobacillus, and were dispersed into five species: L. plantarum (25.33%), L. fermentum (22.66%), L. pentosus (12%), L. brevis (10.66%), and L. diolivorans (1.33%). Minor populations of the other genera, included: Enterococcus (faecium and faecalis) (18.66%), Leuconostoc citreum (5.33%) and Pediococcus (acidilactici and pentosaceus) (3.99%). All of the strains of L. plantarum and L. brevis were subjected to rep-PCR typing. High intra-species diversity was found among L. plantarum and L. brevis isolates. It was concluded that poly-phasic strategies, based on molecular techniques, are necessary for reliable and accurate studying of the microbial composition of fermented products.

Field of study: Agricultural and Food sciences
Proton radiation damage at low temperature in GaAs and GaN light-emitting diodes

It is shown that the radiation hardness for light emission in light-emitting diodes (LEDs) is substantially improved at low temperatures. This is demonstrated through measurements of light emission at room and low temperatures from amphoteric Si-doped gallium arsenide, gallium arsenide quantum well and gallium nitride quantum well LEDs following proton irradiation at room and low temperatures. The enhanced low-temperature radiation hardness for light emission in these LEDs is explained in terms of an improvement in radiative efficiency due to a reduction of nonradiative transition probability at low temperatures. Further, lattice displacement damage in these devices due to irradiation at room temperature is compared with the corresponding damage at low temperatures. Our results show that the amount of lattice damage is dependent on irradiation temperature.

Field of study: Physics
Future structural biology applications with a free-electron laser - more than wild dreams?

A workshop entitled Potential Future Applications in Structural Biology of an X-ray Free-Electron Laser at DESY was held at Hamburg, Germany, on 4-8 July 1999. The aim of the workshop was to identify and discuss potential applications in structural biology using the specific beam properties of the planned X-ray free-electron laser at DESY, Hamburg. The workshop focused on proposals in X-ray crystallography, spectroscopy, microscopy and holography. In the discussions during the workshop, the response of biological material to the expected high photon flux and its time dependence played a central role. Technological aspects in data recording and image interpretation were covered as well. There was general agreement that an X-ray free-electron laser source with its specific source parameters could offer unique opportunities for novel experiments in structural biology, complementing current synchrotron facilities. The realization of future applications will be challenged by the handling of large high-energy doses on the biological specimen and the development of equipment capable to respond to a pulse time structure in the femtosecond range.

Field of study: Physics
Comparative Study of Preconceived Scientific Ideas Held by Different Groups of Junior Secondary School Students in Niger State, Nigeria

This study investigates the preconceptions of junior secondary school students in Niger State on scientific ideas. The sample was made up of three hundred and sixty (360) junior secondary school students (JSSS I) who were randomly selected from twelve secondary schools. Four schools in each three educational zones with thirty (30) students from each school (15 males and 15 females) were used. The research instrument used was a 24 items of preconceptions on scientific ideas scale (POSIS) adapted by the researcher to obtain students’ preconceptions on scientific ideas. Five experts in science education validated the instrument. A reliability coefficient of 0.78 and 0.80 were obtained for the instrument using test-retest method and Cronback alpha analysis respectively. Four hypotheses were formulated and tested. Data collected by means of the instruments were analyzed using the mean, standard deviation, t-test and ANOVA statistics. The study revealed that the gender of the respondents did not influence their preconceived knowledge on scientific ideas. (t-cal=1.42, df =358, p< 0.05). The preconceptions across the three educational zones in the state did not differ significantly. (F-cal=2.76, DF= 357 and 2, p< 0.05). There was no significant difference between the responses of students from rural and urban schools on preconceived ideas about selected scientific ideas. (t-cal=1.36, df =477, p< 0.05). However, it is revealed that the private school students responded more positively to the statements than did their counterparts in public schools. (t-cal=3.28, df= 477, p< 0.05).  Based on the findings, recommendations were made, among others, that science curriculum for Nigeria be reviewed to include basic ethnographic and ethno science concepts which will facilitate the deep understanding of scientific concepts and acquisition of appropriate scientific skills.  Preconceptions, Scientific ideas, School Location and Type

Field of study: Education
Estimation of the volatility distribution of organic aerosol combining thermodenuder and isothermal dilution measurements

A method is developed following the work of Grieshop et al. (2009) for the determination of the organic aerosol (OA) volatility distribution combining thermodenuder (TD) and isothermal dilution measurements. The approach was tested in experiments that were conducted in a smog chamber using organic aerosol (OA) produced during meat charbroiling. A TD was operated at temperatures ranging from 25 to 250 °C with a 14 s centerline residence time coupled to a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a scanning mobility particle sizer (SMPS). In parallel, a dilution chamber filled with clean air was used to dilute isothermally the aerosol of the larger chamber by approximately a factor of 10. The OA mass fraction remaining was measured as a function of temperature in the TD and as a function of time in the isothermal dilution chamber. These two sets of measurements were used together to estimate the volatility distribution of the OA and its effective vaporization enthalpy and accommodation coefficient. In the isothermal dilution experiments approximately 20 % of the OA evaporated within 15 min. Almost all the OA evaporated in the TD at approximately 200 °C. The resulting volatility distributions suggested that around 60–75 % of the cooking OA (COA) at concentrations around 500 µg m−3 consisted of low-volatility organic compounds (LVOCs), 20–30 % of semivolatile organic compounds (SVOCs), and around 10 % of intermediate-volatility organic compounds (IVOCs). The estimated effective vaporization enthalpy of COA was 100 ± 20 kJ mol−1 and the effective accommodation coefficient was 0.06–0.07. Addition of the dilution measurements to the TD data results in a lower uncertainty of the estimated vaporization enthalpy as well as the SVOC content of the OA.

Field of study: Environmental science
Energy and transport gaps in etched graphene nanoribbons

We report transport measurements on etched graphene nanoribbons. We show that two distinct voltage (i.e. energy) scales can be experimentally extracted for characterizing the parameter regions of suppressed conductance at low charge density in graphene nanoribbons. The energy scales are related to the charging energy of localized states and to the strength of the disorder potential. We discuss the scaling behaviour of these two energy scales as a function of the minimum width w for a number of different devices. Finally, we present a model based on Coulomb blockade, due to quantum dots forming inside the nanoribbon, explaining the observed energy scales.

Field of study: Materials science