nils-herrmann/clean_scirepeval huggingface dataset:
Heavy metals residues and trace elements in milk powder marketed in Dakahlia Governorate.

Fifty random milk powder samples were collected from different outlets in Dakahlia Governorate, Egypt and analyzed by Atomic Absorption Spectrophotometer to determine heavy metals residues and trace elements [lead (Pb), Cadmium (Cd), aluminium (Al), iron (Fe), selenium (Se) and manganese (Mn)]. The average concentration of Pb, Cd, Al, Fe, Mn and Se in examined milk powder samples were 0.791; 0.322; 1.57; 20.41; 0.497 and 0.014 ppm, respectively. All examined samples of milk powder had Pb, Cd, Fe, and Mn residues over the permissible limit. At the meanwhile, 96 and 58% of examined samples had Al and Se levels above the permissible limit, respectively. The calculated daily intake of Pb, Cd, Al, Fe, Mn and Se from consumption of 200 ml reconstituted milk powder per day were 158.5; 64.4; 313.4; 4082; 99.4 and 2.8 μg, respectively, which contributed about 31.64; 92.0; 26.12; 85.04; 1.99 and 3.5% from the Acceptable Daily intake of these elements, respectively. Public health significance and hazardous of these metals were discussed.

Field of study: Agricultural and Food sciences
Surface growth kinematics via local curve evolution

A mathematical framework is developed to model the kinematics of surface growth for objects that can be generated by evolving a curve in space, such as seashells and horns. Growth is dictated by a growth velocity vector field defined at every point on a generating curve. A local orthonormal basis is attached to each point of the generating curve and the velocity field is given in terms of the local coordinate directions, leading to a fully local and elegant mathematical structure. Several examples of increasing complexity are provided, and we demonstrate how biologically relevant structures such as logarithmic shells and horns emerge as analytical solutions of the kinematics equations with a small number of parameters that can be linked to the underlying growth process. Direct access to cell tracks and local orientation enables for connections to be made to the underlying growth process.

Field of study: Biology, Mathematics
Preparation of Au-Pt Nanostructures on Highly Oriented Pyrolytic Graphite Surfaces by Pulsed Laser Deposition and Their Characterization by XPS and AFM Methods

Au-Pt nanostructures on highly oriented pyrolytic graphite (HOPG) were prepared by irradiating bimetallic target under ultrahigh vacuum with pulsed radiation of Nd:YAG laser. The deposited nanostructures were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The measured spectra of Au (4f) and Pt (4f) photoelectrons of laser deposits were composed of two overlapping doublets. Analysis of images obtained from AFM revealed bimodal particle size distribution and presence of few large particles. In agreement with AFM images of the deposit we attributed a two doublet structure of Au (4f) and Pt (4f) spectra to bimodal nanoparticle size distribution. Carbon KLL Auger electron spectra revealed formation of defects in the superficial layers of HOPG by impinging metal ions accompanied by appearance of sp 3 hybridized carbon atoms. The dependence of Au (4f) and Pt (4f) core level binding energies on the amount of metals deposited and formation of bimetallic nanoparticles are discussed.

Field of study: Chemistry
Potential Role of microRNA-183 as a Tumor Suppressor in Hepatocellular Carcinoma

Disseminated tumors, known as metastases, are responsible for ninety-percent of mortality due to cancer. Epithelial to mesenchymal transition, a phenomenon required for morphological conversion of non-motile discoid shaped epithelial cells to highly motile spindle-shaped mesenchymal cells, is thought to be a pre-requisite for metastatic progression. Metastasis-associated 1 (MTA1) protein is a prime inducer of EMT and metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the molecular mechanisms that regulate the expression and function of MTA1 in HCC have not been elucidated.  In silico prediction algorithms were used to find microRNAs (miRNAs) that may target MTA1. We examined the relationship between the expression of MTA1 and miR-183 using quantitative real time PCR. We also determined the levels of the MTA1 protein using immunohistochemistry. Reporter assays, in the presence and absence of the miR-183 mimic, were used to confirm MTA1 as a bona fide target of miR183. The effect of miR-183 on HCC pathogenesis was determined using a combination of in vitro migration and invasion assay, together with in vivo xenograft experiments. The correlation between miR-183 and MTA1 expression was also studied in samples from HCC patients, and in The Cancer Genome Atlas dataset.  Analysis of the sequence database revealed that MTA1 is a putative target of miR-183. MTA1 protein and RNA expression showed opposite trends to miR-183 expression in breast, renal, prostate, and testicular tissue samples from cancer patients, and in the metastatic HCC cell line HepG2. An inverse correlation was also observed between MTA1 (high) and miR-183 (low) expression within samples from HHC patients and in the TCGA dataset. Reporter assays in HepG2 cells showed that miR-183 could inhibit translation of a reporter harboring the wild-type, but not the mutant miR-183 3’-untranslated region (UTR). In addition, miR-183 significantly inhibited in vitro migration and invasion in HepG2 cells, and in vivo hepatic metastasis.  Our results reveal a novel post-transcriptional regulatory mechanism for MTA1 expression via miR-183, which is suppressed during HCC pathogenesis.

Field of study: Biology, Chemistry
Staking Claims: Confronting Capetown

Confronting Cape Town Cape Town One City Festival September 22 October 6 1999 Curator: Emma Bedford Venue:The Granary, Buitenkant Street, Cape Town N ot very long ago. the world had a clear picture of South Africa as a country which in the space of a few years had miraculously mutated from the universally despised oppressive apartheid regime to a true democracy. It is a picture which has inevitably blurred and lost the sharpness of focus as time and global attention moved on. The minutiae of programmes of reconstruction and rehabilitation, the personal struggles of reassessment, the backsliding into old habits, the difficult processes of integration can never be as dramatic as the grand gesture of the official takeover by the heroes of the struggle from their former oppressors.

Field of study: Art
Differentially 4-Uniform Permutations with the Best Known Nonlinearity from Butterflies

Many block ciphers use permutations defined over the finite field F22k with low differential uniformity, high nonlinearity, and high algebraic degree to provide confusion. Due to the lack of knowledge about the existence of almost perfect nonlinear (APN) permutations over F22k, which have lowest possible differential uniformity, when k > 3, constructions of differentially 4-uniform permutations are usually considered. However, it is also very difficult to construct such permutations together with high nonlinearity; there are very few known families of such functions, which can have the best known nonlinearity and a high algebraic degree. At Crypto’16, Perrin et al. introduced a structure named butterfly, which leads to permutations over F22k with differential uniformity at most 4 and very high algebraic degree when k is odd. It is posed as an open problem in Perrin et al.’s paper and solved by Canteaut et al. that the nonlinearity is equal to 22k−1−2k. In this paper, we extend Perrin et al.’s work and study the functions constructed from butterflies with exponent e = 2i + 1. It turns out that these functions over F22k with odd k have differential uniformity at most 4 and algebraic degree k +1. Moreover, we prove that for any integer i and odd k such that gcd(i, k) = 1, the nonlinearity equality holds, which also gives another solution to the open problem proposed by Perrin et al. This greatly expands the list of differentially 4-uniform permutations with good nonlinearity and hence provides more candidates for the design of block ciphers.

Field of study: Computer science, Mathematics
The Influence of Pension Scheme Maturity on Investment Strategies of Pension Funds in Kenya

The longevity risk borne by members of defined contribution pension schemes and the funding risk borne by sponsors of defined benefit pension funds have shifted attention to the investment strategies employed by pension funds. We use secondary data from 206 occupational retirement benefits schemes in Kenya, to examine the influence of pension scheme maturity on investment strategies. We then triangulate the results using focused group discussions with industry experts. Results from the regression models indicate that scheme maturity does not influence the investment strategies of occupation schemes in Kenya contrary to life cycle theory. The Retirement Benefits Authority and trustees of retirement benefits schemes in Kenya are advised to offer members’ investment choices coupled with education to enable them make decisions to reduce their exposure to risky assets as they age.

Field of study: Business
The Changing Role of Government in Community Services: Issues of Access and Equity to Administrative Review

Governments are increasingly moving to privatise, or contract out many community services and functions previously the responsibility of the public sector. Consumers of community services stand to benefit from this trend toward contracting out. However, it is also apparent that there is a need to ensure that improved avenues of review, redress and safeguards accompany these changes in delivery and decision making.

Field of study: Political science
Monte-Carlo simulation of scattering correction for quantitative neutron imaging system

Neutron digital imaging is a low light level imaging technique.It is difficult to extract the quantitative information of samples due to the image degradation caused by scattering neutrons in the imaging process.In this situation,the principle of so-called scattering degradation of the low light level neutron imaging system is analyzed,and the degradation process in this system is characterized by point spread function(PSF) superposition.Using Monte Carlo method,the PSF is simulated and modeled as an analytical function of two parameters,the thickness of sample and the distance from sample to detector,and then the calculation method of PSF is presented.The result shows that constructing the PSF of this system and applying it to scattering correction for neutron images is an effective scattering correction method for quantitative neutron radiography,which has the theoretically guiding significance for reducing the adverse effect on imaging quality induced by scattering neutrons.

Field of study: Physics
Geomicrobiology of extremely acidic subsurface environments.

Extreme acidophiles (microorganisms with pH optima of < 3) can colonize and exploit subterranean environments, such as abandoned metal sulfide mines, that have the potential for developing widespread or isolated pockets of acidity. Although acidophiles can utilize a wide range of electron donors, inorganic materials (reduced sulfur, ferrous iron, and possibly hydrogen) are often the most abundant sources of energy for acidophiles in the subsurface. The diversity and interactions of acidophilic microbial communities in two abandoned sulfide mineral mines (in Iron Mountain, California, and the Harz mountains in Germany) and a sulfidic cave (Frasissi, Italy) are reviewed. In addition, the contrasting geomicrobiology of two abandoned sulfide mineral mines in north Wales is described. Both are extremely acidic (pH~2) and low-temperature (8-9 °C) sites, but one (Cae Coch) is essentially a dry mine with isolated pockets of water, while the other (Mynydd Parys) contains a vast underground lake that was partially drained several years ago. The microbial communities in these two mines exhibit different relative abundances and often different species of archaea and bacteria. Wooden pit props, submerged in the underground lake, act as a slow-release source of organic carbon in the subterranean Mynydd Parys lake, supporting a microbial community that is more enriched with heterotrophic microorganisms.

Field of study: Biology, Environmental science
N-terminal methionine in recombinant proteins expressed in two different Escherichia coli strains.

Two genes coding for chloramphenicol acetyltransferase and human interferon gamma, respectively, were overexpressed constitutively in two different strains of Escherichia coli (E. coli LE392 and E. coli XL1). The N-terminal amino acid analysis of the purified proteins showed that: (a) the N-terminal methionine is processed more efficiently in E. coli LE392 rather than in E. coli XL1 cells; (b) the N-terminal methionine is removed better from the heterologous human interferon gamma in comparison with the homologous chloramphenicol acetyltransferase protein: and (c) there is no strong correlation between the efficiency of N-terminal procession and the yield of recombinant protein.

Field of study: Biology, Engineering
Mediodorsal thalamic lesions impair radial maze performance in the rat.

The role of the mediodorsal thalamic nucleus (MD) in spatial memory processes was assessed. Animals were preoperatively trained on an 8-arm maze placed in a visually deprived environment. Following 50 acquisition trials, one group received bilateral electrolytic lesion of the MD thalamus, whereas the other group received sham lesions. On postoperative tests of radial maze performance, MD lesioned animals made significantly more errors, made more errors sooner, and emitted fewer correct responses before making an error than did sham controls. The lesioned subjects also exhibited considerable perseveration immediately postoperation and developed response patterning on postlesion trials. Lesions of the mediodorsal thalamus may fundamentally compromise memory systems and alter ability to respond appropriately in a minimally cued environment.

Field of study: Biology, Psychology
Microscopic Description of Unconventional Nodal Superconductivity in FeSe

Finding of unconventional superconductivity (USC) in FeSe in an electronic "normal" state with broken $C_{4v}$ rotational symmetry testifies to the diversity of pairing states in Fe-based superconductors. Moreover, such USC emerges as a direct instability of a normal state without Landau Fermi liquid quasiparticles, increasingly dubbed a `strange' metal. Here, we combine inputs from a first-principles correlated electronic structure method (LDA+DMFT) and symmetry analyses to propose a novel mechanism for unconventional nodal superconductivity as a direct instability of an incoherent bad-metal without Landau Fermi-liquid quasiparticles. We find that a ferro-quadrupolar order, with novel spin quadrupoar correlations enhances orbital-selective Mottness in FeSe, and competes with unconventional nodal superconductivity with $s_{\pm}$-pair symmetry. We support our proposal by demonstrating good accord with spectral and magnetic fluctuation data, and rationalize the strain and pressure dependence of $T_{c}$ by appealing to competition between superconductivity and electronic ferro-quadrupolar order.

Field of study: Physics
Growth of pre-B cells in cultures of bone marrow from children with acute lymphoblastic leukaemia and other diseases.

Pre-B cells from the bone marrow of children with acute lymphoblastic leukaemia (ALL) survived up to 144 hr after the completion of treatment and divided in culture with maximum cell numbers at 24 hr. There was no rise in B cell number and no evidence of differentiation from pre-B to B cells. Binucleated pre-B cells in cultures containing cytochalasin B confirmed that pre-B cell division was occurring. Cycloheximide reduced cell numbers in culture but bromodeoxyuridine did not. Pre-B cell numbers also increased in culture of morphologically normal marrows from treated and untreated patients with solid tumours, and probably in normal marrows from patients with non-malignant diseases.

Field of study: Biology, Medicine
Nitrogen stress induced changes in the marine cyanobacterium Oscillatoria willei BDU 130511.

Exclusion of combined nitrogen (NaNO3) from the growth medium caused certain changes in metabolic processes leading to cessation in growth of the non-heterocystous, non nitrogen-fixing marine cyanobacterium Oscillatoria willei BDU 130511. But antioxidative enzymes, namely superoxide dismutase and peroxidase, helped the organism to survive the nitrogen stress. Prominent effects observed during nitrogen starvation/limitation were: (i) reduction of major and accessory photosynthetic pigments, (ii) impairment of photosynthesis due to loss of one major Rubisco isoenzyme, (iii) reduced synthesis of lipids and fatty acids, (iv) modifications of protein synthesis leading to the repression of three polypeptides and synthesis of two new polypeptides, (v) enhanced glutamine synthetase and reduced nitrate reductase activities, (vi) enhanced production of hydrogen peroxide and (vii) induced appearance of four new peroxidase isoenzymes. The observed metabolic changes were reversible, and the arrested growth under prolonged nitrogen deficiency could be fully restored upon subculturing in freshly prepared ASN III medium containing nitrogen (NaNO3). The present study demonstrates the capability of a non-nitrogen-fixer to withstand nitrogen stress making it an ecologically successful organism in the marine environment. The above pleiotropic effects of nitrogen deficiency also demonstrate that nitrogen plays a crucial role in growth and metabolism of marine cyanobacteria.

Field of study: Biology, Environmental science
Social Psychology and the Study of Sexual Behavior

Past research on sexual behavior may be viewed as a progressive evolution from less taboo concerns (animal behavior, studies of primitive cultures, and abnormality) to the succession of "shocks" that attended the extension of sexual knowledge to the normal, contemporary human sphere with Freud, Kinsey, and Masters and Johnson. Social psychologists were attracted to this area by the revolutionary societal changes in attitudinal permissiveness and in actual behavior, by the research initiated by the Commission on Obscenity and Pornography, and by a pressing applied interest in solving the problems of unwanted and unneeded conception. Sex research is of special value to our field because it has built-in experimental impact, its technology includes the direct nonverbal assessment of a motivational-emotional state, and it is of obvious relevance to innumerable real- life issues. Upon examination, many of the traditional principles and research paradigms of social-personality psychologists may be perceived as being directly relevant to an understanding of sexuality. A tentative model of a social psychological approach to this research domain (the Sexual Behavior Sequence) is presented. Finally, the interdisciplinary and international aspects of sex research are noted.

Field of study: Psychology
Steady-state characteristics of a GaAs injection quantum amplifier receiving a narrow-band input signal

An investigation was made of the amplifying characteristics of a stripe homojunction laser in which positive feedback was suppressed by orienting the axis of the active region at an angle to the cleaved end faces. Radiation from a conventional cw stripe homojunction laser emitting a single mode was used as the input signal. An analysis was made of the output power and spectral characteristics of the amplifier as a function of the rate of pumping of the amplifier and of the amplitude of the input signal. It was found that the gain exceeded 103 in the linear amplification regime and that the superradiant background was almost completely suppressed when the amplification process was saturated by a sufficiently strong input signal. An optical filter with a pass band 0.1 nm wide was placed at the amplifier exit and in this configuration the amplifier sensitivity was 0.4×10−7W.

Field of study: Engineering, Physics
Effects of Heat Treatment on Properties of Iron-based Composite Materials

In order to improve the life of composite material on iron-based surface,with a high surface hardness and wear resistance,good plasticity and toughness,effects of heat treatment process on iron-based composite materials were studied.The results show that: after oil quenched at 980 ℃,180 ℃,tempered 4 h at 200 ℃,the matrix structure is strengthened,the hardness increases by 9%,and toughness increases by 11%.Heat treatment has no effects on the hardness of composite layer.

Field of study: Materials science
Game Constraints, Player Verbalizations, and Mathematics Learning

In two phases (clinical and empirical) the effects of game constraints on the quantity and quality of mathematical verbalizations during game playing and on the amount of student learning were examined. Subjects were 114 fourth- and fifth-grade students. During the clinical phase, small groups of students were videotaped while playing mathematics games. Alternating some game constraints seemed to alter both the quantity and quality of verbalizations. For selected variations of game constraints found during the clinical phase to affect verbalizations, four small pretest-posttest experiments indicated no achievement effects.

Field of study: Education
Experimental Study of Potential Heat Treatment Issues of Large Bi-2212 Coils

The route to 30 T NMR endorsed by a recent National Academy report  clearly still has many challenges to achieve a high stability and a homogeneous high-temperature superconducting (HTS) insert magnetic field. As the only HTS conductor with round wire (RW) geometry, Bi2Sr2CaCu2 O8-x (Bi-2212) RW conductor is very attractive for nuclear magnetic resonance (NMR) magnet applications. At present, an NMR quality demonstration magnet with Bi-2212 RW wound insert coils is under development at the National High Magnetic Field Laboratory. The target of this demonstration magnet is to generate a total field of 23+ T with ppm level homogeneity. Since Bi-2212 coils require wind-and-react technology, our initial major concern was that large Bi-2212 coils might deform during the typical partial melt Bi-2212 heat treatment (HT) due to their large self-weight. To experimentally mimic the HT of large Bi-2212 coil, several small test coils were heat treated under deadweight loads. After 1 bar Bi-2212 full reaction, these coils were characterized in terms of coil geometry, transport critical current (Ic) properties, oxygenation status, and insulation performance. Coil geometry and individual wire shape were in fact not distorted, nor was transport property degradation induced by mechanical loading. Uniform oxygen equilibration was achieved in these coils even though they were coated with dense oxide insulation. However, although the TiO2-based insulation coating was well preserved on the wire surface, several coils developed electrical shorts.

Field of study: Physics