nils-herrmann/clean_scirepeval huggingface dataset:
Dynamics of a fluid core with inward growing boundaries

In both physical and mathematical models of the Earth's core it has been difficult, so far, to discuss all the terms in the magneto-hydrodynamic energy equation under one unifying theory and to relate all the physical mechanisms involved in a specific model. The reason for this is mainly the uncertainty about the energy sources, or, when they could be accounted for, with uncertainty about their location. In the following article we deduce and examine a model of the Earth's core which can be regarded as a sequel to theories of the formation of a fluid core in the course of the Earth's thermal evolution. General cooling and pressure-freezing cause the formation of solid phases at the boundaries of the fluid core, leading to a solid inner core (IC) and a lower mantle shell (Bullen's D" layer) from slow overgrowth at the mantle-core (MC) boundary. For simplicity, the core fluid is assumed to consist of two major phases, one conducive to solid metallic core formation, and the other to crystallization of a lower mantle phase from "solution" in a metal "solvent." The presence of a third, minor constituent, by selective partitioning between phases, acts as a solid phase growth regulator. On the basis of this model the energy available for fluid core motion and thereby for maintenance of the magnetic field, is related directly to the time rate of change of the growth of the solid phases at the IC and MC boundaries. Most of the available energy is gravitational and is associated with density and concentration currents which offset density inhomogeneities caused by selective acceptance and rejection of the fluid core constituents by the two solid phases. A very conservative estimate of the net gain per second in gravitational potential energy resulting from the mass redistribution via density currents and solid phase formation is 2.6 x 10" W which may become available in different forms. The fraction which is converted into kinetic energy associated with differential circulatory motion around the rotation axis amounts to 3.4 x 10" W, based on radial interchange with respect to the Earth's centre. The heat liberated as a result of IC solidification is 2.7 x loL1 W, assuming that the metallic phase is mainly iron. Since our ideas of other constituents of the core fluid are less definite we can draw only very general conclusions about the MC boundary. If silicates and oxides are likely candidates, it is possible that in the crystallization of the mantle phase from the core fluid, heat is being absorbed, thus creating a heat sink at the MC boundary. An estimate of the net strain energy associated with compression of IC material by about 1.4% and expansion of MC material by, on the average, 0.4% gives 1.5 x 10'' W. Magnetic polarity reversals might be explained as due to epochs during which the solid phase growth rate which dominates the fluid motion shifts from the IC to the MC boundary and vice versa. Intensity changes might be due to significant variations in the ratio of the radial and horizontal velocity components of the fluid motion.

Field of study: Environmental science
Improved Hybrid HMM-SVM Method for Handwritten Chinese Signature Verification

An improved hybrid HMM-SVM method for Handwritten Chinese Signature Verification is proposed.First HMM is used as discriminative feature transformation and data compression for two kinds of training data of signature.Then the multidimensional probability output vectors of HMM are treated as the input vectors for SVM.At last in order to improve the performance of verification,the output vectors of SVM are transformed to a posterior probability through sigmoid function.Some experiments with this method are made on the SVC2004 Signature database.The result indicates that the proposed method can get better performance such as lower EER compared to HMM,SVM and HMM-SVM.

Field of study: Computer science
Topgehalte diere = topgehalte boere : bedryf

Die jaarlikse De Heus On-farm Challenge, wat onlangs in KwaZulu-Natal gehou is, het weer eens uitstaande diere gelewer en was 'n goeie voorbeeld van die algemene gehalte van die koeie wat tans in die provinsie aangetref word.

Field of study: Agricultural and Food sciences
Probabilistic optimization techniques for multicast key management

The logical key hierarchy (LKH) scheme and its derivatives are among the most efficient protocols for multicast key management. Traditionally, the key distribution tree in an LKH-based protocol is organized as a balanced binary tree, which gives a uniform O(log n) complexity for compromise recovery in an n-member group. In this paper, we study improving the performance of LKH-based key distribution protocols by organizing the LKH tree with respect to the members' rekeying probabilities instead of keeping a uniform balanced tree. We propose two algorithms, which combine ideas from data compression with the special requirements of multicast key management. Simulation results show that these algorithms can reduce the cost of multicast key management significantly, depending on the amount of variation in the rekey characteristics of the group members.

Field of study: Computer science
Memory in St. Bonaventure and the Moment of Coming to be as a Human Being

Bonaventure's work on memory is drawn from his work on the Soul's Journey to God. In the third chapter he writes "on Contemplating God through His Image stamped upon our Natural Powers" (Bonaventure, 79). Contemplation requires that the heart leads and the intellect follows. In this way a growth in understanding may lead us to a greater love than we had ever dreamed of achieving (Bonaventure, 56. Prologue to SJG). Bonaventure's intent, and mine, is that we may learn from ourselves as images of God in our human nature. Thence our relationship with our Creator may become more secure and peaceful for realizing the moment of our creation in its memorized actuality. In order to encourage depth to our thinking, I have presented material from John McDowell on the contact and involvement of the human mind with the world in which we live. This work, though from an adult perspective, throws light on the condition of babes in the womb and children in their development. Gopnik et al. draw our attention to the computational state of children's minds, which is quite clear from their research. Their work admonishes us to respect the developing conceptus more than past generations did in this regard. The human being is a great person from conception to adulthood and beyond. There are eight headings under which I aim to unfold some appreciation of this greatness.

Field of study: Medicine, Philosophy
Stable isotope constraints on the role of graphite in the genesis of unconformity-type uranium deposits

The Key Lake unconformity-type uranium deposit occurs in a shear zone where it intersects the unconformity between Archean and Aphebian gneisses and the overlying Proterozoic Athabasca Group sandstones. The roots of the Key Lake and many other unconformity-type uranium deposits in the Athabasca basin are close to gneisses rich in graphite and most deposits have small amounts of carbonaceous materials (bitumen and hydrocarbon buttons) within and around altered basement and sandstone ore zones. In many Athabasca uranium deposits, hydrothermal fluids have destroyed graphite disseminated in the strongly altered gneisses in the vicinity of the deposits, prompting some to suggest that graphite was converted to CH4, which reduced and precipitated the uranium and partially condensed to form bitumen. The δ13C values of graphite collected from unaltered and altered gneisses around the Key Lake deposit have a limited range (−25 ± 5) and are not a function of distance from the mineralization or the intensity of alter...

Field of study: Environmental science
CALCULATION METHOD FOR CRACK WIDTH IN RAC BEAM BASED ON LONG-TERM LOADING EFFECTS

Based on long-term crack width experiments on recycled aggregate concrete(RAC) beams with different recycled material replacement rates, the development of crack widths over time between the different beams was compared. The results show that the period of rapid cracking growth is postponed in recycled aggregate concrete beams, and also of longer duration than in normal concrete beams. The internal lever arm coefficient, average crack spacing, and steel strain non-uniformity coefficient were fitted, and a formula for calculating maximum short-term crack width is established. Its calculation results have satisfactory precision.After analyzing additional crack width time-varying coefficients, formula for maximum crack width an RAC beam with varying replacement rates is established.

Field of study: Engineering
Social thought in America : the revolt against formalism

Spend your few moment to read a book even only few pages. Reading book is not obligation and force for everybody. When you don't want to read, you can get punishment from the publisher. Read a book becomes a choice of your different characteristics. Many people with reading habit will always be enjoyable to read, or on the contrary. For some reasons, this social thought in america the revolt against formalism tends to be the representative book in this website.

Field of study: Political science
Inhibition of mitogen-activated protein kinase by a Drosophila dual-specific phosphatase.

The Drosophila extracellular signal-regulated kinase (DERK) mitogen-activated protein kinase (MAPK) is involved in the regulation of multiple differentiation and developmental processes. Tight control of MAPK activity is critical for normal cell behaviour. We identified a novel Drosophila MAPK phosphatase (DMKP) cDNA from the expressed-sequence-tag database and characterized it. Analysis of the nucleotide sequence revealed an open reading frame encoding the 203-amino acid protein, with a calculated molecular mass of 23 kDa, which has a high amino acid sequence similarity with 'VH1-like' dual-specific phosphatases at the broad region near the catalytic sites. The expression of DMKP mRNA occurs from the late larval stages to adulthood in Drosophila development. The recombinant DMKP protein produced in yeast retained its phosphatase activity. When expressed in Schneider cells, DMKP dose-dependently inhibited DERK and Drosophila c-Jun N-terminal kinase activities with high selectivity towards DERK. However, DMKP did not have any affect on Drosophila p38 activity. When DMKP was expressed in yeast, it down-regulated the fus1-lacZ trans-reporter gene of the pheromone MAPK pathway without any significant effect on the high-osmolarity-glycerol-response pathway.

Field of study: Biology, Computer science
Plasma Treatments of Melt-Extruded Blend Sheets of Recycled PET/Poly(ε-caprolactone)

Melt-extruded sheets of blends of recycled poly(ethylene terephthalate) (R-PET) with poly(ε-caprolactone) (PCL) were exposed to plasmas of different reactivity; non-oxidative Ar and N2, and oxidative O2. Mass loss by etching and morphology changes to the surfaces were investigated with regard to the discharge power effects as well as the plasma gas source reactivity. The sheets of PCL and PCL-rich blends were more susceptible to the oxidative plasmas, although still resistant to non-oxidative plasmas. Generation of microstructures was observed on wavy or granular forms of morphology of the original sheets after the plasma treatments, according to the SPM observations.

Field of study: Materials science
Intermediate Coherent–Incoherent Charge Transport: DNA as a Case Study

We study an intermediate quantum coherent-incoherent charge transport mechanism in metal-molecule-metal junctions using Buttiker’s probe technique. This tool allows us to include incoherent effects in a controlled manner, and thus to study situations in which partial decoherence affects charge transfer dynamics. Motivated by recent experiments on intermediate coherent-incoherent charge conduction in DNA molecules, we focus on two representative structures: alternating (GC)n and stacked GnCn sequences; the latter structure is argued to support charge delocalization within G segments and, thus, an intermediate coherent–incoherent conduction. We begin our analysis with a highly simplified one-dimensional tight-binding model while introducing environmental effects through Buttiker’s probes. This minimal model allows us to gain fundamental understanding of transport mechanisms and derive analytic results for molecular resistance in different limits. We then use a more detailed ladder-model Hamiltonian to repre...

Field of study: Physics
Long-term effectiveness of a multifaceted intervention on pain management in a walk-in clinic.

Pain is a common complaint of patients attending walk-in clinics, but timely and appropriate pain management is often lacking.



To evaluate the impact of a multifaceted intervention on pain management.



Prospective interventional study.



Three cross-sectional surveys were conducted: before, 4 months after and 14 months after a multifaceted intervention at the medical walk-in clinic of a university hospital. The intervention included both educational activities and structural changes. Use of recommended pain management procedures, pain relief and overall assessments of pain treatment and health professionals' attitudes were assessed using patient questionnaires, collected by mail. History of pain, records of pain intensity and use of pain medication were extracted from medical files.



We analysed 1409 medical files and 695 questionnaires of patients presenting with pain. Documentation of pain intensity and administration of pain medication at the walk-in clinic improved significantly 14 months after the intervention (7% vs. 53% and 17% vs. 27%, respectively, p<0.001) and pain medication was more often administered by the oral route (14% vs. 23%, p<0.001). However, no change was observed for complete pain relief (40% vs. 39%, p=0.92) or patients' overall assessments of pain management.



The intervention improved adherence to recommended procedures, even in the longer term, but did not result in better patient outcomes. Continuing efforts are needed to help health professionals improve pain management in out-patient care.

Field of study: Medicine
BIGINELLI REACTION – AN EFFECTIVE METHOD FOR THE SYNTHESIS OF DIHYDROPYRIMIDINE DERIVATIVES

A brief review of the publications over the past 5 years devoted to the synthesis of 3,4-dihydropyrimidin-2(1 H )-one or -thione derivatives using Biginelli reaction is presented. The impact of reaction conditions (solvents, catalysts, energy input) on the yield is discussed. New combinations of reagents enabling the synthesis of a wide range of 3,4-dihydropyrimidin-2(1 H )-one derivatives with various functional groups are considered.

Field of study: Chemistry
Control of human vigilance by concurrent schedules.

Twenty four subjects were studied for ten 1-hr sessions to determine whether the human observer's visual monitoring of individual meters in a complex display can be differentially controlled by concurrent scheduling of signals. Subjects were divided into two main groups of 12 each. One group was given fixed-interval, variable-interval, and differential-reinforcement-of-low-rates schedules. The second group was given fixed-interval, fixed-ratio, and differential-reinforcement-of-low-rates schedules. Test subjects were instructed only to detect as many signals as possible. Results indicated that observing responses to the individual meters corresponded to the temporal patterns known to be associated with the schedules for the group given fixed-ratio instead of variable-interval as a component schedule. The group given the variable-interval schedule in the three-schedule combination tended to exhibit the same pattern of viewing across each of the three meters during any given session. However, subsequent testing was performed on two more subjects over 64 sessions, by adding initial feedback of signal detection results, and instructions concerning schedule construction. These results indicated that with knowledge of schedule construction and initial feedback of detection data, differentiated responding can be maintained efficiently over long periods of time by the combination including fixed-interval, variable-interval, and differential-reinforcement-of-low-rates schedules.

Field of study: Biology, Psychology
The Insertion of Local Wisdom into Instructional Materials of Bahasa Indonesia for 10th Grade Students in Senior High School

This current study aimed at investigating Bahasa Indonesia textbooks with regards to local wisdom issues. The preliminary study was utilized as the basis for developing instructional materials of Bahasa Indonesia that are rich of characters. Bahasa Indonesia instructional materials containing local wisdoms not only equip students with broad knowledge, but strong characters as well. Qualitative research method was employed for the purpose of this current study. After analyzing the contents of seven Bahasa Indonesia textbooks for Grade 10 Senior High School, there were some tapped local wisdoms. However, some of texts were subject to changes, replaced by various texts originating from a number of regions throughout Indonesia. Those intended texts contained more local wisdoms and contributed to students’ broadened knowledge about diversities in Indonesia.

Field of study: Education
Multiple kinds of optimal impulse control strategies on plant-pest-predator model with eco-epidemiology

Yongzhen etźal. (2010) describe a mathematical model of a scenario where a plant population is imported to a pest-predator system with an infected pest. Thus a plant-pest-predator eco-epidemiological model disturbed by an impulsive effect is proposed. First of all, the stability conditions of the susceptible pest-eradication periodic solution for eradicating the susceptible pest are investigated. Compared with the results in (Yongzhen etźal., 2010), the presence of the plant population increases the cost of natural enemies as well as the demand for insecticide. In addition, we study the effect of the death rate of the infected pest on pest control in terms of evolution of virulence and the basic reproductive number. Results show that larger mortalities of the infected pest will lead to the frustrated invasion or the instability of susceptible pest-eradication periodic solutions. Next, we focus on the four kinds of optimal impulsive control strategies, biological control, chemical control, and integrated control with fixed period or variable period, to maximize the yields of plants at the terminal time with minimum efforts. All the optimal control problems are solved via a time scaling technique and a gradient-based optimization method. Our results show that two parameters, the amount of sprayed infective pest and the kill fraction of the susceptible pest, play a key role in improving the yield of the plants. In addition, for the four kinds of control strategies, our results also show that biological control is more effective than chemical control to achieve an optimal solution, and the last two strategies can produce higher yields than the first two control strategies.

Field of study: Mathematics
Discovery of the First Low-luminosity Quasar at z > 7

We report the discovery of a quasar at z = 7.07, which was selected from the deep multi-band imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. This quasar, HSC J124353.93+010038.5, has an order of magnitude lower luminosity than do the other known quasars at z > 7. The rest-frame ultraviolet absolute magnitude is M1450 = -24.13 +/- 0.08 mag and the bolometric luminosity is Lbol = (1.4 +/- 0.1) x 10^{46} erg/s. Its spectrum in the optical to near-infrared shows strong emission lines, and shows evidence for a fast gas outflow, as the C IV line is blueshifted and there is indication of broad absorption lines. The Mg II-based black hole mass is Mbh = (3.3 +/- 2.0) x 10^8 Msun, thus indicating a moderate mass accretion rate with an Eddington ratio 0.34 +/- 0.20. It is the first z > 7 quasar with sub-Eddington accretion, besides being the third most distant quasar, known to date. The luminosity and black hole mass are comparable to, or even lower than, those measured for the majority of low-z quasars discovered by the Sloan Digital Sky Survey, and thus this quasar likely represents a z > 7 counterpart to quasars commonly observed in the low-z universe.

Field of study: Physics
Design of Phase Codes for Radar Performance Optimization With a Similarity Constraint

This paper deals with the design of coded waveforms which optimize radar performances in the presence of colored Gaussian disturbance. We focus on the class of phase coded pulse trains and determine the radar code which approximately maximizes the detection performance under a similarity constraint with a prefixed radar code. This is tantamount to forcing a similarity between the ambiguity functions of the devised waveform and of the pulse train encoded with the prefixed sequence. We consider the cases of both continuous and finite phase alphabet, and formulate the code design in terms of a nonconvex, NP-hard quadratic optimization problem. In order to approximate the optimal solutions, we propose techniques (with polynomial computational complexity) based on the method of semidefinite program (SDP) relaxation and randomization. Moreover, we also derive approximation bounds yielding a ldquomeasure of goodnessrdquo of the devised algorithms. At the analysis stage, we assess the performance of the new encoding techniques both in terms of detection performance and ambiguity function, under different choices for the similarity parameter. We also show that the new algorithms achieve an accurate approximation of the optimal solution with a modest number of randomizations.

Field of study: Engineering
Development Needs of Volunteer Pharmacy Practice Preceptors

To determine the training needs and interests of volunteer pharmacy preceptors.  Volunteer preceptors (n=576) were surveyed on various aspects of precepting and their needs related to additional training.  Two hundred thirty-six preceptors (40.9%) responded. Preceptors were less confident about enforcing attendance policies, identifying and managing unmotivated or failing students, identifying dishonesty or plagiarism, and handling conflict. While only 29.5% of respondents agreed that having an APPE student decreased their overall workload, approximately half (48.1%) indicated that student pharmacists helped them complete their daily tasks and 67.8% agreed that APPE students extended patient care. Respondents who had received training were significantly more confident than preceptors who had not received training in their abilities to clarify expectations, evaluate a student's knowledge, and foster skills related to critical thinking and problem solving.  Training programs for pharmacy preceptors are effective; however, important areas in which additional training is needed or desired were identified among both new and experienced preceptors.

Field of study: Education, Medicine
Study on ultrasonic extraction process of arecoline from betel nut

To use ultrasonic-assisted extraction process to extract arecoline from betel nut.The content of the arecoline which was used as evaluating criteria,was determined by HPLC.Based on the results of single factor experiments,the optimum extracting process of arecoline from betel nut was optimized by L9(34) orthogonal test.The optimized extraction process was as follows:the concentration of ethanol was 85%;the ratio of solid to liquid was 1:8;the extraction temperature was 65 ℃;the pH value of alkalization was 8.The extraction rate of arecoline was 0.1987%.The purity of arecoline extraction was 98.1%(W).

Field of study: Agricultural and Food sciences