nils-herrmann/clean_scirepeval huggingface dataset:
Phenomena of Beach and Dune-sands

Beach-sands.  The following notes concerning certain phenomena of beach and dune-sands have an interest for the reason that they seem to explain some of the conditions under which the arenaceous materials of the seashore journey before they come to rest in stratified deposits. Incidentally they show some facts as to the part which the coastal sands take in protecting the shore from the action of the sea. These observations are the result of work done on the eastern coast of the United States in connection with the tasks which have fallen to me as geologist of the Atlantic Coast Division of the United States Geological Survey.  One of the most noticeable features which is exhibited by beach sands is their extraordinary endurance of the beating of the waves. On examining any pebbly beach exposed to the ocean-surges we readily perceive that the masses . . .

Field of study: Geology
Effect of Gd and Cu on the Structural, Electrical, and Dielectric Properties of MnFeO3 Nanomaterials Synthesized 
by the Sol–Gel Method

Substituted GdxMn1−xFe1−yCuyO3 (x = 0.0–1.0; y = 0.0–0.5) nanoparticles were synthesized by sol–gel auto-combustion, and the effect of Gd and Cu content on their structural, electrical, and dielectric properties was investigated. X-ray diffraction data confirmed formation of an orthorhombic single phase with crystallite size in the range 23–61 nm. Particle size was determined by scanning electron microscopy. Direct current electrical resistivity and activation energy were observed to increase from 2.14 × 107  to 7.46 × 1010 Ω cm and from 0.64 to 0.70 eV, respectively, with increasing substituent concentration, whereas drift mobility decreased from 3.27 × 10−13 to 1.19 × 10−16 cm2 V−1 S−1. Dielectric constant, dielectric loss, and dielectric loss factor decreased with increasing frequency and with increasing Gd and Cu content. These decreases in dielectric properties with increasing electrical resistivity suggest the materials could be used in microwave devices.

Field of study: Materials science
Experimental designs for estimating the correlation between two destructively tested variables

A specimen can have two or more important strength properties. These could be its bending strength and tensile strength. Assuming joint normality, we study experimental designs for estimating the correlation coefficient. The specimen is proof loaded—say, in bending. If it does not fail, it is loaded in tension to failure. Optimal proof loads are determined. Large sample properties of the maximum likelihood estimator are also given.

Field of study: Mathematics
Comment on "Perfect Andreev reflection due to the Klein paradox in a topological superconducting state (Nature \textbf{570}, 344 (2019))"

In a recent publication, Lee $et$ $al.$ discussed experimental observation of Klein tunneling into a proximity-induced topological superconducting state of SmB$_{6}$ through the measurement of Andreev reflection with low-bias conductance doubling across point-contact junctions between sharp Pt-Ir tips and SmB$_{6}$/YB$_{6}$ heterostructures. However, the interpretation of the presented point-contact data is rather ambiguous because observing a low-bias conductance enhancement by a factor of 2 is not special for Klein tunneling into topological superconductors. Such an enhanced conductance can be observed in point contacts between all types of superconductors and normal metals when the contacts are neither in the ballistic nor in the diffusive regimes of mesoscopic transport, but in a dissipative thermal regime. The thermal regime is expected for the point contacts presented in Lee $et$ $al.$ primarily because of the anticipated very short electron mean free path of SmB$_6$ -- we will discuss this in more detail here.

Field of study: Physics
On uniqueness of time-consistent Markov policies for quasi-hyperbolic consumers under uncertainty

We give a set of sufficient conditions for uniqueness of a time-consistent Markov stationary consumption policy for a quasi-hyperbolic household under uncertainty. To the best of our knowledge, this uniqueness result is the first presented in the literature for general settings, i.e. under standard assumptions on preferences, as well as some new condition on a transition probability. This paper advocates a ''generalized Bellman equation'' method to overcome some predicaments of the known methods and also extends our recent existence result. Our method also works for returns unbounded from above. We provide few natural followers of optimal policy uniqueness: convergent and accurate computational algorithm, monotone comparative statics results and generalized Euler equation.

Field of study: Economics
Ottoman De-Industrialization, 1800-1913: Assessing the Magnitude, Impact, and Response

India and Britain were much bigger players in the eighteenth-century world market for manufactures than were Egypt, the Levant, and the core of the Ottoman Empire, but these eastern Mediterranean regions did export carpets, silks, and other textiles to Europe and the east. By the middle of the nineteenth century, they had lost most of their export market and much of their domestic market to globalization forces and rapid productivity growth in European manufacturing. How different was the Ottoman experience from the rest of the poor periphery? Was de-industrialization more or less pronounced? Was the terms of trade effect bigger or smaller? How much of Ottoman de-industrialization was due to falling world trade barriers such as ocean transport revolutions and European liberal trade policy, how much due to factory-based productivity advance in Europe, how much to declining Ottoman competitiveness in manufacturing, how much to Ottoman railroads penetrating the interior, and how much to Ottoman policy? This article uses a price-dual approach to seek the answers.

Field of study: Economics, History
A computer-controlled system for studying ammonia exchange, photosynthesis and transpiration of plant canopies growing under controlled environmental conditions

A fully automatic growth chamber system was built in order to study NH3, exchange and NH3, compensation points of plant canopies growing under controlled environmental conditions in which atmospheric NH3, concentrations corresponded to those naturally occurring over terrestrial ecosystems. The system included plant cuvettes with separate root and shoot compartments constructed of coated polycarbonate. This material did not change the spectral composition of photosynthetically active light and had a low adsorption of NH3, and water vapour. Atmospheric NH3, concentrations in the inlet of the cuvettes were controlled by mass-flow controllers. Inlet and outlet NH3, concentrations were measured on-line with a modified chemiluminescent NH3, monitor. At airflow rates per unit leaf area of about 3 dm3 m−2 s−1, the system allowed accurate determinations of NH3, exchange rates down to about 0.1 nmol NH3, m−2 s−1. The NH3, compensation points at anthesis for barley cultivars Laevigatum and Golf were 4.2±2.8 and 4.6±2.9nmol mol−1 of NH3, in air (SE, n=4), respectively. NH3, absorption in both cultivars increased linearly with atmospheric NH3, concentration in the range 0–30 nmol mol−1 of NH3, in air. NH3, absorption was much higher in the light than in the dark, indicating a strong stomatal and/or metabolic control of NH3, exchange. Photosynthesis and transpiration were not affected by exposure to NH3, concentrations in the range 0–30nmol mol−1 for 7d.

Field of study: Environmental science
The role of mesolimbic dopamine in conditioned locomotion produced by amphetamine.

Daily administration of psychomotor stimulants in a distinctive environment can impart on the environment stimulantlike properties. Rats injected with amphetamine (0.75 mg/kg, sc) daily for 5 days exhibited a robust unconditioned locomotor response, measured in photocell cages, and showed a conditioned locomotor response when treated with saline on the 6th day. This conditioned locomotor response was found to be significantly attenuated by 6-hydroxydopamine (6-OHDA) lesions of the nucleus accumbens when the lesion was made either pre- or postconditioning. Similarly, although rats with 6-OHDA lesions of the nucleus accumbens exhibited a robust supersensitive unconditioned locomotor hyperactivity in response to apomorphine (0.1 mg/kg, sc), they did not show a conditioned response on the test day. These results suggest that the mesolimbic dopamine system may be responsible for both the unconditioned and conditioned locomotor responses to psychomotor stimulant drugs. Further, conditioned locomotion depends on a critical interaction between the physiological release of presynaptic dopamine and occupation of postsynaptic receptors.

Field of study: Biology, Psychology
Nuclear Saturation and Correlations

The relation between nuclear saturation and NN-correlations is examined. Nucleons bound in a nucleus have a reduced effective mass due to the mean field. This results in off-energy-shell scatterings modifying the free-space NN-interaction by a dispersion correction. This is a major contribution to the density-dependence of the effective in-medium force and to saturation. Low-momentum effective interactions have been derived by renormalisation methods whereby correlations may be reduced by effectively cutting off high momentum components of the interaction. The effect of these cut-offs on dispersive corrections and on saturation is the main focus of this paper. The role of the tensor-force, its strength and its effect on correlations is of particular interest. The importance of the definition of the mean field in determining saturation as well as compressibility is also pointed out. 
With a cut-off below $\sim 2.6 fm^{-1}$ there is no saturation but at lower density the binding energy is still well approximated suggesting that such a force may be useful in nuclear structure calculations of (small) finite nuclei if saturation is not an issue. 
A separable interaction that fits experimental phase-shifts exactly by inverse scattering methods is used. Recent experiments measure short ranged correlations (SRC's) to be 0.23 for $^{56}Fe$. Other experiments have obtained a depletion of occupation-numbers in $^{208}Pb$ to be $\sim 0.2$. For nuclear matter with the separable interaction and a continuous spectrum we obtain the related quantity $\kappa$ to be 0.175 with the Bonn-B deuteron parameters, while Machleidt's gets $\kappa= 0.125$ for the Bonn-B potential and a continuous spectrum.

Field of study: Physics
Citrus Rust Mite, Phyllocoptruta oleivora (Ashmead) (Eriophyidae: Acarina): Effect of its Damage on Fruit Quality and its Chemical Control

The mite damaged fruits were found to have less fruit weight, fruit size, juice volume and titrable acidity. The infestation caused more rind thickness, total soluble solids, sugars and ascorbic acid contents, comparatively. Mancozeb (0.5%) proved best in controlling the mite. The efficacy of other pesticides in controlling the rust mite in the descending order are: monocrotophos (0.05%), dicofol (0.1%), phosalone (0.5%), wettable sulphur (0.4%), Mitac (0.05%), triazophos (0.05%), profenophos (0.05%), neem formulation (Azadirachtir. 0.5%) and Anona (0.5%).

Field of study: Biology
Synthesis of peroxyacetyl nitrate in air by acetone photolysis

The photodecomposition of acetone in air with NO 2 admixed has been used to generate peroryacetyl nitrate (PAN) either by batch synthesis in an isolated flask or in a continuous-flow reactor. With NO 2 mixing ratios near 10 ppm, the method converts in the first case 88% of NO 2 to PAN and ∼6% to methyl nitrate within a time period of a few minutes. In the second case, the conversion is ∼90% and 10%, respectively. The reproducibility is better than 5%. The PAN mixing ratio produced by batch synthesis declines exponentially with time due to wall-catalyzed thermal decomposition

Field of study: Environmental science
Giant Prostatic Calculus Associated with Giant Urethral Calculus

We report 2 cases of giant prostatic calculi associated with giant renal calculi. Both patients were advanced in age and had a long history of urethral strictures and urinary tract infection. They were anemic and their serum creatinine levels were also raised. Diagnosis in both cases was made by rectal examination, and confirmed by plain radiography. Treatment was by suprapubic cystolithotomy preceded by retrograde manipulation of the urethral calculi after control of their urinary tract infection. Both patients made an uneventful recovery, and required regular dilatations of their urethral strictures.

Field of study: Medicine
Cisuralian and Guadalupian global paleobiogeography of fusulinids in response to tectonics, ocean circulation and climate change

During the Permian, major icehouse-greenhouse climate shifts and tectonic reconfiguration had important biogeographic implications, especially for climate-sensitive organisms such as fusulinids. Here we present multivariate methods on a global fusulinid species dataset including 1546 species from 58 localities in the Early (Asselian, Sakmarian, Artinskian and Kungurian) and Middle (Roadian, Wordian and Capitanian) Permian. Our results show that fusulinid global provincialism was high in the Asselian, Sakmarian, and Artinskian, driven by the development of multiple fusulinid bioregions in and near the Tethys Ocean. During the Asselian, Uralian sites and nearby regions of western Tethys were distinct from eastern Tethys, while stations in Arctic Russia and Norway formed a separate Boreal bioregion. Tectonic closure of the oceanic gateway in the southern Urals resulted in progressive isolation of the Uralian and Boreal bioregions during the Sakmarian and Artinskian and their ultimate disappearance by the Kungurian. Climate warming likely was the most important control on the Sakmarian formation of the distinct peri-Gondwana bioregion, because its development coincided with deglaciation following the Late Paleozoic Ice Age but preceded the separation of the Cimmerian terranes from northern margin of Gondwana. On the other hand, northward movement of the Cimmerian blocks following Artinskian-Kungurian rifting ultimately led to the merger of the peri-Gondwanan bioregion with tropical Tethyan faunas, resulting in lower provincialism in the Guadalupian and minimal faunal differentiation across Tethys. In contrast, faunal similarity between Tethys and eastern Panthalassa (the McCloud region and southwestern United States) was higher in the Asselian-Artinskian but decreased in the Kungurian and Middle Permian, perhaps as the result of sluggish ocean circulation following the warming episode of Late Paleozoic deglaciation.

Field of study: Environmental science, Geography
Black Power and the Transformation from Protest to Policies

In a retrospective examination of black power in 1977, Dianne Pinderhughes analyzed a sample of the speeches and writings of individuals and organizations that had been prominent in the development and articulation of the concept. She found that there was only a narrow area of common agreement on the elements of black power and that on close examination even in this narrow area the common elements were so vague and general "as to be meaningless as far as giving specific direction to participants at the grassroots level."' Joel Aberbach and Jack Walker found similar evidence at the grassroots level. In their study of the attitudes of a sample of Detroit residents, black and white, they found that the overwhelming majority of whites evaluated black power negatively, while opinion among blacks was divided: 42.2 percent were favorable and 49.6 percent were unfavorable. Those who evaluated it favorably saw black power as a call for black unity and an expression of a desire for a fair share of society's opportunities; those who viewed it unfavorably saw it as meaningless.2 And in the early scholarly commentaries on the meaning of black power, one finds similar disagreement.3 Thus, at the elite level, at the

Field of study: Political science
MULTI-OBJECTIVE OPTIMIZATION OF MAGNETORHEOLOGICAL FLUID DAMPERS

Based on the finite element analysis of magnetic field, taking damping force and its adjustment ratio as two objective functions, utilizing multi-objective genetic algorithm (MOGA), the optimum design of MRF damper was completed. Based on optimal solutions, the response surface and linear correlation coefficient matrix were analyzed. The results indicate that, the most highly influential factors of the damping force and its adjustable ratio are as follows: the gap between the cylinder and the piston, the ratio between the effective length of the piston and the gap, the effective area of the piston. The gap between the cylinder and the piston and the ratio between the effective length of the piston and the gap itself have the greatest influence on the damping force and the force’s adjustment ratio respectively. The results also show that the damping force and the adjustment ratio are two conflicting objectives; consequently, they can not be improved simultaneously. Moreover, with a specific restriction for the factor of the damping force, the effective length of the piston has an optimal value.

Field of study: Engineering
Late Quaternary marine stratigraphy southeast of New Zealand

Sediment cores of late Quaternary age from the continental margin and deep sea (Bounty Trough) southeast of New Zealand reveal an alternating sequence of glacial and interglacial sediments. During glacial episodes of lowered sea level, glaciation in the Southern Alps was at its peak, and east coast rivers delivered enormous volumes of terrigenous sediments to the shelf edge. At these times, sediments of the deep adjacent basins were dominated by micaceous hemipelagic deposits with a low biogenic component consisting mostly of siliceous remains (radiolaria and sponge spicules). Planktonic foraminifera, although present, were much reduced in abundance because of increased dissolution, as in deeper water subantarctic cores farther to the south. Cool-water forms dominated.

During interglacial episodes, terrigenous sediment supply to the deep basins was reduced in response to higher sea levels and as glaciers retreated and deposited much of their loads in newly formed glacial lakes and on the plains. Terrigenous sediment dilution of the biogenic portion was thus much reduced. Calcium carbonate dissolution also was reduced. These processes, in combination, led to the deposition of foraminifera-rich hemipelagic sediments. Siliceous biogenic productivity decreased.

Thus, the late Quaternary marine sediment record in the area adjacent to southeast New Zealand is dominated by paleoclimatic influences that control terrigenous input, calcium carbonate dissolution, biogenic productivity, and the migration of planktonic assemblages.

Field of study: Geology
Challenges and resilience in the lives of urban, multiracial adults: an instrument development study.

Multiracial Americans represent a rapidly growing population (Shih & Sanchez, 2009); however, very little is known about the types of challenges and resilience experienced by these individuals. To date, few psychological measures have been created specifically to investigate the experiences of multiracial people. This article describes 2 studies focused on the development and psychometric properties of the Multiracial Challenges and Resilience Scale (MCRS). The MCRS was developed using a nationwide Internet sample of urban, multiracial adults. Exploratory factor analyses revealed 4 Challenge factors (Others' Surprise and Disbelief Regarding Racial Heritage, Lack of Family Acceptance, Multiracial Discrimination, and Challenges With Racial Identity) and 2 Resilience factors (Appreciation of Human Differences and Multiracial Pride). A confirmatory factor analysis with data from a second sample provided support for the stability of this factor structure. The reliability and validity of the measure, implications of these findings, and suggestions for future research are discussed.

Field of study: Psychology
A Urinary Metabonomics Research on Total Ginsenoside Treated Diabetes Cardiomyopathy Rats Based on Rapid Resolution Liquid Chromatography/Mass Spectrometry: A Urinary Metabonomics Research on Total Ginsenoside Treated Diabetes Cardiomyopathy Rats Based on Rapid Resolution Liquid Chromatography/Mass 

A urinary metabonomics method based on rapid resolution liquid chromatography/mass spectrometry (RRLC/MS) was developed to study the effect mechanism of Total Ginsenoside (TG) on streptozotocin(STZ) induced Diabetic Cardiomyopathy (DCM) rats. Twenty-four STZ-induced diabetic rats were randomly divided into DCM group and TG group. DCM group was administrated with TG 30 mg/kg body weight once a day by gastric irrigation. TG group was administrated with water by gastric irrigation in parallel. Ten healthy rats were defined as control group and were also administrated with water by gastric irrigation in parallel. After twelve-week continuous irrigation, 24 h urine samples of rats in the three group were collected and analyzed by RRLC/MS. Principal component analysis (PCA) was carried out for pattern recognition and a clear separation between DCM rats and those treated with TG was achieved. Three potential biomarkers were found and identified. The significant changes of these biomarkers indicated the pharmacological effects of TG on the metabolism of rats. TG can regulate the metabolism of body include citrate cycle, fatty acid metabolism and oxidative stress. The results shows the metabonomics is a useful tool in effect mechanism research of natural product and this work is helpful in the effect mechanism study of Panax ginseng.

Field of study: Chemistry
Role of College Teachers in Educating the Youth in the Changing Society

We  live in a rapidly changing society. In fact , love for change and progress is inherent in human nature. It is this reason why man, since the dawn of human civilization, has been trying to make adjustment to physical and social world around  him.But in this age of globalization and information communication revolution , this change has been even more rapid and dramatic, affecting our life styles, our ways of thinking , feeling and acting . The youth, like any other section of people simply can not remain unaffected  by this change. Teachers as educators have sacred duty to educate and guide the youth to cope with this rapidly changing society. The College teachers who are considered to be highly intellectual section of the society have even a bigger role to play in this regard. An attempt has been made in this paper to throw some light on the role to be played by the teachers in general and the College teachers in particular  in educating and guiding the youth in the fast changing society.

Field of study: Education
A homotopy method for nonlinear inverse problems

We develop a homotopy method for nonlinear inverse problems, where the forward problems are governed by some forms of differential equations. A Tikhonov-style regularization approach yields an optimization problem. Ordinary iterative methods may fail to solve this problem, due to their locally convergent properties. Then the fixed-point homotopy method is introduced to solving the normal equation of the optimization problem, and a new and globally convergent algorithm is constructed, which is highly effective in the aspects of speed of computation, ability of noise suppression and wide region of convergence. As a practical application, the method is used to solve the inverse problem of 2-D acoustic wave equation. We demonstrate the merits and effectiveness of our algorithm on two realistic model problems.

Field of study: Mathematics