nils-herrmann/clean_scirepeval huggingface dataset:
Assessment of Knowledge and Competences in Agricultural Engineering Acquired by the Senior Secondary School Students for Farm Mechanisation

This study was designed to assess the agricultural engineering knowledge and competencies acquired by the senior secondary students for farm mechanization in technical colleges in Ebonyi state of Nigeria. A survey research design was adopted for the study. Three research questions and two null hypotheses guided the study. The population of the study was 1,858 comprising of 174 teachers and 1,684 final year students. A simple random sampling technique was used to select 370 as sample for the study. A structured questionnaire with 21 items was employed for the study. The instrument was face validated by 3 experts. Two of the experts from the Department of Technology and Vocational education while one specialist from measurement evaluation, all from Ebonyi State University; and the reliability coefficient of 0.183 was obtained using Cronbach alpha technique to determine the internal consistency of the instrument. The data collected were analyzed using weighted mean and standard deviation for the research questions white t-test statistics was used to test for the hypotheses at 0.05 level of significant. The result of the analysis of the data reveals that the students have the knowledge in recognizing and identifying tillage machines, tools and equipment but do not have the competencies in the use of tillage, planting, weeding and harvesting farm machines tools and equipment except the use of simple farm tools like hoe, spade and sickle. The result of the hypotheses showed that there was no significant difference in the opinions of the teachers and the students on the knowledge and the competencies acquired by the senior secondary students in agricultural engineering for farm mechanization. It was recommended among others that the teachers should expose the students more on the practical use of the tillage, planting, weeding and harvesting farm machines, tools and equipment.  Knowledge, competences, agricultural engineering, secondary school students

Field of study: Education
Rigorous definition and analysis of program complexity measures: An example using nesting

Two deficiencies persist in program complexity measures research: a lack of formalism in defining complexity measures and a lack of analytical tools for evaluating these measures. The lack of formalism significantly hinders independent empirical evaluations of proposed measures. The lack of analytical tools and techniques for evaluating measures makes comparisons between independent research efforts difficult. As an example of one attempt to avoid these deficiencies, we formally define “nesting” for arbitrary (not necessarily well-structured) programs and use this definition to redefine four existing measures of nesting that have appeared in the literature. We then define one simple tool that can be used to evaluate nesting measures. Application of this tool to the redefined measures reveals in one case that the proposed measure does not adequately quantify the nesting represented by the simple tool. In the other three cases the measures are demonstrably similar. Analogous analytical evaluations of proposed measures prior to the requisite empirical studies are encouraged.

Field of study: Computer science, Engineering
Circular Hall Effect in a rod conductor

We discover the circular Hall Effect in a conducting rod sample. The uniform current flow in a rod can be viewed as a carrier drift in crossed the radial Hall electric field and the azimuthal magnetic field caused by the current itself. Arguing the diamagnetic currents could define the correct boundary condition at the inner rod surface we find the nonuniform density of longitudinal current taking into account the finite viscosity of 3D electron liquid. Unexpectedly, under certain condition the resistivity of the rod sample vanishes exhibiting the transition to zero-resistance state. At the transition the magnetic field is shown to be pushed out of the sample bulk. The critical temperature of the transition is calculated.

Field of study: Physics
Absolute measurement of LDR brachytherapy source emitted power: Instrument design and initial measurements.

Energy-based source strength metrics may find use with model-based dose calculation algorithms, but no instruments exist that can measure the energy emitted from low-dose rate (LDR) sources. This work developed a calorimetric technique for measuring the power emitted from encapsulated low-dose rate, photon-emitting brachytherapy sources. This quantity is called emitted power (EP). The measurement methodology, instrument design and performance, and EP measurements made with the calorimeter are presented in this work.



A calorimeter operating with a liquid helium thermal sink was developed to measure EP from LDR brachytherapy sources. The calorimeter employed an electrical substitution technique to determine the power emitted from the source. The calorimeter's performance and thermal system were characterized. EP measurements were made using four (125)I sources with air-kerma strengths ranging from 2.3 to 5.6 U and corresponding EPs of 0.39-0.79 μW, respectively. Three Best Medical 2301 sources and one Oncura 6711 source were measured. EP was also computed by converting measured air-kerma strengths to EPs through Monte Carlo-derived conversion factors. The measured EP and derived EPs were compared to determine the accuracy of the calorimeter measurement technique.



The calorimeter had a noise floor of 1-3 nW and a repeatability of 30-60 nW. The calorimeter was stable to within 5 nW over a 12 h measurement window. All measured values agreed with derived EPs to within 10%, with three of the four sources agreeing to within 4%. Calorimeter measurements had uncertainties ranging from 2.6% to 4.5% at the k = 1 level. The values of the derived EPs had uncertainties ranging from 2.9% to 3.6% at the k = 1 level.



A calorimeter capable of measuring the EP from LDR sources has been developed and validated for (125)I sources with EPs between 0.43 and 0.79 μW.

Field of study: Medicine, Physics
Multiple Comparison of Several Linear Regression Models

Research on multiple comparison during the past 50 years or so has focused mainly on the comparison of several population means. Several years ago, Spurrier considered the multiple comparison of several simple linear regression lines. He constructed simultaneous confidence bands for all of the contrasts of the simple linear regression lines over the entire range (-∞, ∞) when the models have the same design matrices. This article extends Spurrier's work in several directions. First, multiple linear regression models are considered and the design matrices are allowed to be different. Second, the predictor variables are either unconstrained or constrained to finite intervals. Third, the types of comparison allowed can be very flexible, including pairwise, many–one, and successive. Two simulation methods are proposed for the calculation of critical constants. The methodologies are illustrated with examples.

Field of study: Mathematics
Evidence of low dose effects of the antidepressant fluoxetine and the fungicide prochloraz on the behavior of the keystone freshwater invertebrate Gammarus pulex.

In recent years, behavior-related endpoints have been proposed as rapid and reliable ecotoxicological tools for risk assessment. In particular, the use of detritivores to test the toxicity of pollutants through feeding is currently becoming a well-known method. Experiments combining feeding with other behavioral endpoints can provide relevant information about direct and indirect toxicological effects of chemicals. We carried out a feeding experiment with the shredder Gammarus pulex in order to detect indirect (through leaf conditioning) and direct effects (through water exposure) of two pollutants at environmentally relevant concentrations: the fungicide prochloraz (6 μg/L) and the antidepressant fluoxetine (100 ng/L). Prochloraz inhibited fungal growth on leaves, but it did not affect either the microbial breakdown rates or the C:N ratio of the leaves. Individuals of G. pulex that were fed with treated leaves presented lower consumption rates, not only those fed with prochloraz-treated leaves, but also those fed with fluoxetine-treated leaves, and those fed with the mixture-treated leaves. Mixed-effects models revealed that the swimming velocity of the amphipods after the experiment was modulated by the exposure to fluoxetine, and also by the exposure to prochloraz. We demonstrate that both the antidepressant and the fungicide may cause significant sublethal effects at low concentrations. The combination of behavioral endpoints together with the application of mixed models provided a useful tool for early detection of the effects of toxicity mixtures in freshwater ecosystems.

Field of study: Environmental science
Effects of different altitudes on main physical and mechanical properties of bamboo

The main physical and mechanical properties of bamboo was measured to investigate the effects of different altitudes on those properties.The results show that both of the air-dry density and basic density increase along with axial height and the altitude increasing.The basic density of bamboo at foot and top of the hill are 0.699 g·cm-3 and 0.715 g·cm-3,and the air-dry density are 0.798 g·cm-3 and 0.827 g·cm-3 respectively.Both the density differences between the bamboo at foot and top of the hill are significant.The modulus of elasticity in static bending,the compressive strength parallel to grain and the bending strength of bamboo at foot and top of the hill are 12 368.28 MPa 11 934.07 MPa,55.858 MPa 59.840 MPa and 183.203 MPa 196.293 MPa respectively.Among them,the differences between the compressive strength parallel to grain,the bending strength of bamboo at foot and top of the hill are also significant.

Field of study: Agricultural and Food sciences
Atmospheric and low pressure metalorganic vapor phase epitaxial growth of vertical quantum wells and quantum well wires on submicron gratings

Nonplanar metalorganic vapor phase epitaxial growth on submicron gratings has been studied. Growth conditions have been determined to preserve the grating structure and also to enhance the formation of crescent shaped quantum well wire-like GaAs layers. These growth parameters have been used to grow the layer structure of a quantum well wire (QWW) laser, only needing one growth run. Although there is not yet clear evidence for two-dimensional quantum confinement, this technique offers some interesting perspectives for the realization of QWW lasers.

Field of study: Materials science
Selective Weathering of Dolomite Bodies from a Limestone Host

A weathering pattern in which saccharoidal dolomite is removed from a biopelmicritic limestone may be observed in some Lower Ordovician rocks of central Kentucky. Experiments indicate that the pattern initiates from combined solution and frost wedging. Once established, the selective removal of dolomite is probably spatially concentrated by the preferential collection of water on the rougher dolomite surfaces.

Field of study: Geology
The influence of volition on breathing-swallowing coordination in healthy adults.

This research was designed to clarify the role of cortical modulation in the coordination of respiration and swallowing. Time-locked recordings of submental surface electromyography, nasal airflow, and thyroid acoustics were used to evaluate nonnutritive breathing-swallowing coordination (BSC) and swallowing apnea duration (SAD) of 20 healthy adults during 3 conditions. These conditions represented a continuum of volitional through nonvolitional swallowing control on the basis of a decreasing level of cortical activation: voluntarily initiated swallows during wakefulness, nonvolitional awake swallows, and reflexively initiated swallows during sleep. Differing proportions of swallows at the cusps between inspiration and expiration were found between the volitional and nonvolitional conditions, irrespective of the level of arousal. SAD was unaltered by condition. In conclusion, BSC is influenced by degree of volition but not by level of arousal. This implies that cortical influence on BSC is limited to conditions in which swallowing is voluntarily initiated and indirectly implicates the recruitment of the supplementary motor or insular cortices. SAD remained stable across conditions and may therefore be considered relatively impervious to suprabulbar influence.

Field of study: Biology, Psychology
The effects of 6 antibiotics and berberine on releasing of Shiga-toxin from Escherichia O157∶H7 strains isolated in China

To study the effects of six antibiotics and berberine on production and release of Shiga-toxin of E.coli O157∶H7, which have been frequently used in the antibiotic therapy for bacterial diarrheal diseases in China.  The Shiga-toxin-induced cell death of Vero cells was determined by a colorimetric assay based on the measurement of lactate dehydrogenase (LDH) released into the supernatant from the cytosol of damaged cells.  Growth of all 8 Shiga-toxin(Stx)-producing E.coli O157∶H7 strains in broth containing subinhibitory concentrations of ciprofloxacin, gentamycin, ampicillin, pencillin, streptomycin or erythromycin caused marked increase in the release of Stx. Morever, exposure of E.coli O157∶H7 to berberine also caused observable increase of Stx releases, which has been used wieldy in treatment of diarrheal disease in China for hundreds years.  Since all of the six antibiotics tested and berberine increased Shiga-toxin production and release from E.coli O157∶H7 in vitro, it is suggested that treatment of Stx-producing E.coli infection by these antibiotics at subinhibitory dosage may have significant adverse clinical consequences, such as increasing the possibility of patient developing hemolytic uremic syndrome.

Field of study: Biology
Maximum likelihood estimation of the parameters of discrete fractionally differenced Gaussian noise process

A maximum-likelihood estimation procedure is constructed for estimating the parameters of discrete fractionally differenced Gaussian noise from an observation set of finite size N. The procedure does not involve the computation of any matrix inverse or determinant. It requires N/sup 2//2+O(N) operations. The expected value of the loglikelihood function for estimating the parameter d of fractionally differenced Gaussian noise (which corresponds to a parameter of the equivalent continuous-time fractional Brownian motion related to its fractal dimension) is shown to have a unique maximum that occurs at the true value of d. A Cramer-Rao bound on the variance of any unbiased estimate of d obtained from a finite-sized observation set is derived. It is shown experimentally that the maximum-likelihood estimate of d is unbiased and efficient when finite-size data sets are used in the estimation procedure. The proposed procedure is extended to deal with noisy observations of discrete fractionally differenced Gaussian noise.

Field of study: Engineering
Histone deacetylase inhibitors for treatment of hepatocellular carcinoma

AbstractHepatocellular carcinoma (HCC) is one of the most common cancers in the world. Surgical resection has been considered the optimal treatment approach, but only a small proportion of patients are suitable candidates for surgery, and the relapse rate is high. Approaches to prevent recurrence, including chemoembolization before and adjuvant therapy after surgery, have proven to have a limited benefit; liver transplantation is successful in treating limited-stage HCC because only a minority of patients qualify for transplantation. Therefore, new therapeutic strategies are urgently needed. Because in addition to the classical genetic mechanisms of deletion or inactivating point mutations, epigenetic alterations, such as hyperacetylation of the chromatin-associated histones (responsible for gene silencing), are believed to be involved in the development and progression of HCC, novel compounds endowed with a histone deacetylase (HDAC) inhibitory activity are an attractive therapeutic approach. In particular, pre-clinical results obtained using HA-But, an HDAC inhibitor in which butyric acid residues are esterified to a hyaluronic acid backbone and characterized by a high affinity for the membrane receptor CD44, indicated that this class of compounds may represent a promising approach for hepatocellular carcinoma treatment.

Field of study: Biology, Chemistry, Medicine
The development research on vacuum-packed conditioning pork products

Salt,monosodium glutamate,pepper,star anise and rice wine were used as formulations for technology research in this experiment when fresh pork were raw material.Further study on this basis focused on the effect that brought to the quality of Regulate Pork Products by the technology of static pickled time,static pickled temperature and cooking time in order to research the optimum production of regulate pork products.The result of experiments shows that,when the addition of salt is 1.2 g/100 g,the addition of monosodium glutamate is 1.5 mL/100 g,pepper is 0.2 g/100 g,star anise(1:1) is 0.1 g/100 g,rice wine is 1.5 mL/100 g;static pickled time is 15 h,static pickled temperature is 2 ℃,cooking time is 15min;packaging films using the complex trap vacuum packaging,pasteurization sterilization method selected 65 ℃,30 min.Sterilization of vacuum packaged pork products conditioning with clean,convenient and affordable,etc.,which provide a new way of thinking for the rapid development of fresh pork industry.

Field of study: Agricultural and Food sciences
Dual reactivity of 1,2-disubstituted dihydro-N-heteroaromatic systems. 2. Mechanism of the dehydrogenation of N-acyldihydroquinolines and isoquinolines with 2,2,6,6-tetramethyl-1-oxopiperidinium perchlorate

The mechanism of the heterolytic dehydrogenation of various N-acyl derivatives of α-substituted 1,2-dihydroquinolines and isoquinolines with 2,2,6,6-tetramethyl-1-oxopiperidinium perchlorate was investigated.

Field of study: Chemistry
The Effect of Inquiry Training on Learning Model Using Macromedia Flash and Creativity on Student’s Science Process Skills

This research aimed to determine whether students on science process skills that were learned by inquiry training model using macromedia flash will be better than conventional learning, to know whether the science process skills of students who have creativity above average was better than students who have creativity below the average, to find whether there was an interaction between instructional inquiry training model used macromedia flash with creativity on students process science skill. This research was quasi experiment research with two group pretest-posttest design. The research population was the whole of the XI th grade of SMA Negeri 4 Medan, 2 nd semester of 2016/2017 academic year. The sample of research were taken by cluster random class, consist of 80 students. Class XI-1 was experiment class, consists of 40 students learned by inquiry training on learning model used macromedia flash. Class XI-2 was control class, consists of 40 students taught conventional learning. The instruments consists of two types namely: essay test science process skill consists of 10 questions and essay test of creativity consists of 5 questions. The analyzing of data used Anava two ways. The results showed:  the first hypothesis that the significant on learning model is 0,035 because (sig) 0,05 , H 0 accepted, it meant the science process skills of students who have creativity above average was not better than students who have below average creativity and the third hypothesis showed that the siginficant is 0,252 because (sig)>0,05 so H 0 accepted that there is no interaction between inquiry training model using macromedia flash and conventional learning with creativity in an effort to improve students' science process skills.  Inquiry training model, Conventional, Creativity, Science process skills.

Field of study: Education
Content delivery and caching from a network provider's perspective

An ongoing challenge in telecommunication is to integrate a variety of services on broadband access platforms at increasing transmission speed. Traditional Internet services, such as file transfer, email and web browsing, are now running on common multi-service IP platforms together with voice, video and television over IP, online gaming, P2P downloads, etc. While broadband access is becoming established as standard for homes and via mobile devices, the networking capacities in the access and the backbone are steadily being extended to keep pace with higher traffic volumes. Content delivery (CDN) and peer-to-peer (P2P) networks carry most of today's Internet traffic with different effects on delay and throughput as the main quality-of-service characteristics. We give an overview of the current techniques for distributing content over the Internet via server-based and peer-to-peer overlays regarding their impact on the traffic profiles. We consider link-level measurement on network provider platforms as a basis for network-wide traffic engineering, including load balancing and for current trends and prognosis. Many recent activities in research, industry and standardization have addressed the localized delivery of large content volumes from the network edge and via exchange between peers. The main goal, namely to shorten end-to-end paths and delays, would not only enhance the user experience and benefit network providers by reducing the load in the backbone and on expensive global interconnection links, but would also, last but not least, reduce energy consumption.

Field of study: Computer science
A minimally parametrized branching process explaining plateau phase of qPCR amplification

Quantitative polymerase chain reaction (qPCR) is a commonly used molecular biology technique for measuring the concentration of a target nucleic acid sequence in a sample. The whole qPCR amplification process usually consists of an exponential, a linear and a plateau phase. In qPCR experiments, amplification curves of samples with different template concentrations often, even though not always, have the same plateau height. The biological theory for this phenomenon is that the plateau height is determined by reaction kinetics. Does it mean that the target concentration has no effect on the final plateau height? We proposed a branching process based on Michaelis–Menten kinetics. Our model can describe all phases of qPCR amplification despite its simplicity (it depends on only one parameter). We theoretically showed, through almost sure convergence, that amplification curves will eventually plateau at finite values in any experiment, under any condition. We conclude that the plateau height is largely determined by reaction kinetics but could also be affected by the template concentration. This is in accordance with the current biological theory.

Field of study: Biology, Mathematics
Winding and Testing of YBCO Coils Using Different HTS Wires

YBCO coils with epoxy resin impregnation tend to experience degraded performance, which is due to the mismatch of the thermal contraction coefficients among former, epoxy, and HTS conductors which will generate thermal stresses that induce delamination of the superconducting layer. Several coils have been fabricated and tested, using the YBCO wires from SuperPower Inc. (SP), and Shanghai Superconductor Technology Corporation (SSTC). No degradation of the coil performance was detected for small SP coils, even with epoxy resin impregnation. However, for SP coils and SSCT coils using more than 100 m of YBCO wires, they all exhibited degraded performance after the epoxy resin impregnation. A possible solution to this problem is proposed and a 400 m SSCT coil has been successfully fabricated and tested.

Field of study: Physics