nils-herrmann/clean_scirepeval huggingface dataset:
Inferring 222Rn soil fluxes from ambient 222Rn activity and eddy covariance measurements of CO2

We present a new methodology, which we call Single Pair of Observations Technique with Eddy Covariance (SPOT-EC), to estimate regional-scale surface fluxes of 222Rn from tower-based observations of 222Rn activity concentration, CO2 mole fractions and direct CO2 flux measurements from eddy covariance. For specific events, the regional (222Rn) surface flux is calculated from short-term changes in ambient (222Rn) activity concentration scaled by the ratio of the mean CO2 surface flux for the specific event to the change in its observed mole fraction. The resulting 222Rn surface emissions are integrated in time (between the moment of observation and the last prior background levels) and space (i.e. over the footprint of the observations). The measurement uncertainty obtained is about ±15 % for diurnal events and about ±10 % for longer-term (e.g. seasonal or annual) means. The method does not provide continuous observations, but reliable daily averages can be obtained. We applied our method to in situ observations from two sites in the Netherlands: Cabauw station (CBW) and Lutjewad station (LUT). For LUT, which is an intensive agricultural site, we estimated a mean 222Rn surface flux of (0.29 ± 0.02) atoms cm−2 s−1 with values  > 0.5 atoms cm−2 s−1 to the south and south-east. For CBW we estimated a mean 222Rn surface flux of (0.63 ± 0.04) atoms cm−2 s−1. The highest values were observed to the south-west, where the soil type is mainly river clay. For both stations good agreement was found between our results and those from measurements with soil chambers and two recently published 222Rn soil flux maps for Europe. At both sites, large spatial and temporal variability of 222Rn surface fluxes were observed which would be impractical to measure with a soil chamber. SPOT-EC, therefore, offers an important new tool for estimating regional-scale 222Rn surface fluxes. Practical applications furthermore include calibration of process-based 222Rn soil flux models, validation of atmospheric transport models and performing regional-scale inversions, e.g. of greenhouse gases via the SPOT 222Rn-tracer method.

Field of study: Environmental science
Maximal rank subgroups and strong functoriality of the additive eigencone

Let $G$ be a simple connected complex Lie group. The additive eigencone of $G$ is a polyhedral cone containing the set of solutions to the additive eigenvalue problem, a generalization of the Hermitian eigenvalue problem. The additive eigencone is functorial, and for certain subgroups satisfies a stronger functoriality property: the eigencone of the subgroup is determined by the inequalities of the larger eigencone. Belkale and Kumar first studied this property for subgroups invariant under a diagram automorphism of $G$. We study a new class of subgroups arising from centralizers of torus elements that have the strong eigencone functoriality property.

Field of study: Mathematics
Association of Maternal Serum 25-Hydroxyvitamin D Concentrations with Risk of Gestational Anemia

Vitamin D deficiency has been shown to be associated with a greater prevalence of anemia in various healthy and diseased populations by a great deal of observational studies. However, less work has been done to explore this association in pregnant women. The aim of this study was to evaluate the association between maternal serum 25-hydroxyvitamin D [25(OH)D] concentrations and risk of gestational anemia in a large, nested case-control study.  The serum 25(OH)D concentrations was measured by enzyme immunoassay in 775 pregnant women affected with anemia and 1550 controls. Logistic regression analysis was conducted to assess the association of 25(OH)D concentrations with risk of gestational anemia.  We found the 25(OH)D concentrations was significantly lower in women affected with anemia than in controls. Logistic regression analyses showed that women with 25(OH)D concentrations < 25.0 nmol/L, from 25.0 to 37.4 nmol/L and from 37.5 to 49.9 nmol/L all had increased risk of anemia when compared with women with concentrations from 50.0 to 74.9 nmol/L. And the risk of anemia was significantly increased with the decreasing concentrations of the serum 25(OH)D in a dose-dependent manner (P for trend = 0.012). For women with concentrations < 50.0 nmol/L, they had an 80% increase in anemia risk (95% CI = 1.45-2.25) after adjustment for confounders. We also observed a nonlinear relationship between the serum 25(OH)D and anemia, with a threshold for 25(OH)D of 50.0 nmol/L existed for anemia.  Maternal serum 25(OH)D < 50.0 nmol/L may be a risk factor for gestational anemia, and it should be monitored for the high-risk pregnant women.

Field of study: Biology, Chemistry
Labral Repair Versus Biceps Tenotomy/Tenodesis for the Treatment of Type II SLAP Lesions: Indications and Technique

The majority of surgeons currently favor biceps tenodesis/tenotomy in older patients and labral repair in younger athletes. The case against labral repair is that it may not relieve pain and may result in stiffness. In contrast, I have favored repairing the labrum in nearly all cases and rarely if ever cutting the biceps. Our paper explains why we believe labral repair can result in consistently good results. It is because of this viewpoint that I was anxious to give a full hearing to those who do routinely cut the biceps. Another interesting issue is whether to proceed with surgery at all in the patient with shoulder pain and a type two labral tear. In this regard, the piece by Dr. Schroeder is particularly enlightening . Her landmark paper  found that sham surgery worked as well as labral repair, biceps tenotomy or biceps tenodesis. This is a truly amazing study and at a minimum should serve as a caution for anyone considering SLAP surgery with anything but crystal clear indications. Imaging is another controversial area. Detachment of the biceps anchor, the essential lesion of the potentially operable type II SLAP lesions is particularly difficult to determine from imaging studies. The paper by Dr. Marder explains just what we can tell from advanced imaging studies . This volume also has an international perspective with distinguished surgeons from around the world presenting their views. I hope that it serves its intended purpose of stimulating thought as well as providing guidance.

Field of study: Medicine
Hydropower and the future of Amazonian biodiversity

In an effort to ensure energy independence and exploit mineral resources, the governments of Amazonian countries are embarking on a major dam building drive on the basin’s rivers, with 191 dams finished and a further 246 planned or under construction. This rush to harvest the basin’s vast renewable energy capacity has come without proper consideration of the likely negative environmental externalities on the world’s most speciose freshwater and terrestrial biotas. Here we highlight the economic drivers for hydropower development and review the literature to summarise the impacts of dam building on Amazonian biodiversity. We identify both direct and indirect impacts through the anticipated loss, fragmentation and degradation of riparian habitats. We then propose a series of measures to assess, curb and mitigate the impacts of destructive dams on Amazonian biodiversity.

Field of study: Environmental science
Argentyne bewerk minder, kry meer : fokus op weiding

As dit by die implementering van minimum bewerkingsmetodes kom, het Argentinie 'n besonder goeie rekord wat sy status as landbouland nog verder verbeter. Die vele ooreenkomste tussen Suid-Afrika en Argentinie maak dit beslis die moeite werd om 'n nadere blik te werp op die Argentynse manier van doen.

Field of study: Agricultural and Food sciences
Mode deformation due to self-focusing in injection lasers and its connection with nonlinearity of the output characteristic

The effect of the pump current on the mode configuration of an injection laser with an external selective resonator was studied. It was found that in a single-mode regime, controlled by the external resonator, a number of regularly spaced filamentary channels appear as the pump current is increased. Interference effects give rise to side lobes in the far-field radiation-pattern polar diagram, which are interpreted as being due to self-focusing of the radiation in the active medium, arising from the relationship of the refractive index of the inverted semiconductor with the electron density and the electromagnetic field intensity. The appearance of channels is accompanied by a kink in the energy characteristic of the laser.

Field of study: Engineering, Physics
Proposal for a stationary micro-SQUID

We study a superconducting loop that encloses a magnetic flux, connected to a superconducting and to a normal electrode, when a fixed electric current between the electrodes flows through the loop. The considered circuit does not contain Josephson junctions. We find that in a very broad range of parameters the current flow converges to a stationary regime. The potential difference between the electrodes depends on the magnetic flux, so that measuring this voltage would provide information on the enclosed flux. The sizes of the voltage and of the power dissipation could be appropriate for the design of a practical fluxmeter. We found narrow ranges of flux at which the voltage varies sharply with the flux.

Field of study: Physics
Respective roles of human cytochrome P-4502E1, 1A2, and 3A4 in the hepatic microsomal ethanol oxidizing system.

The microsomal ethanol oxidizing system comprises an ethanol-inducible cytochrome P-4502E1, but the involvement of other P-450s has also been suggested. In our study, human CYP2E1, CYP1A2, and CYP3A4 were heterologously expressed in HepG2 cells, and their ethanol oxidation was assessed using a corresponding selective inhibitor: all three P-450 isoenzymes metabolized ethanol. Selective inhibitors-4-methylpyrazole (CYP2E1), furafylline (CYP1A2), and troleandomycin (CYP3A4)-also decreased microsomal ethanol oxidation in the livers of 18 organ donors. The P-450-dependent ethanol oxidizing activities correlated significantly with those of the specific monooxygenases and the immunochemically determined microsomal content of the respective P-450. The mean CYP2E1-dependent ethanol oxidation in human liver microsomes [1.41+/-0.11 nmol min(-1) (mg protein)(-1)] was twice that of CYP1A2 (0.61+/-0.07) or CYP3A4 (0.73+/-0.11) (p < 0.05). Furthermore, CYP2E1 had the highest (p < 0.05) specific activity [28+/-2 nmol min(-1) (nmol CYP2E1)(-1) versus 17+/-3 nmol min(-1) (nmol CYP1A2)(-1), and 12+/-2 nmol min(-1) (CYP3A4)(-1), respectively]. Thus, in human liver microsomes, CYP2E1 plays the major role. However, CYP1A2 and CYP3A4 contribute significantly to microsomal ethanol oxidation and may, therefore, also be involved in the pathogenesis of alcoholic liver disease.

Field of study: Medicine
Research in computer science: an empirical study

In this paper, we examine the state of computer science (CS) research from the point of view of the following research questions:1.What topics do CS researchers address? 2.What research approaches do CS researchers use? 3.What research methods do CS researchers use? 4.On what reference disciplines does CS research depend? 5.At what levels of analysis do CS researchers conduct research? To answer these questions, we examined 628 papers published between 1995 and 1999 in 13 leading research journals in the CS field. Our results suggest that while CS research examines a variety of technical topics it is relatively focused in terms of the level at which research is conducted as well as the research techniques used. Further, CS research seldom relies on work outside the discipline for its theoretical foundations. We present our findings as an evaluation of the state of current research and as groundwork for future CS research efforts.

Field of study: Computer science, Engineering
Taste-potentiated odor conditioning: impairment produced by infusion of an N-methyl-D-aspartate antagonist into basolateral amygdala.

Two experiments examined the effects of infusing an N-methyl-D-aspartate (NMDA) receptor antagonist, d-2-amino-5-phosphonovalerate(d-APV), on taste-potentiated odor conditioning: a form of learning that is dependent on information processing in 2 sensory modalities. In Experiment 1, rats infused with d-APV were impaired in their acquisition of the potentiated learning to an odor cue. Expression of this learning and acquisition of a simple taste aversion remained intact following drug treatment. In Experiment 2, dose dependence and stereoselectivity were demonstrated for the antagonist compound. These results are consistent with previous studies demonstrating that either basolateral amygdala lesions, or treatment with NMDA antagonists, by other routes (systemic or intraventricular) produce selective deficits in taste-potentiated odor conditioning.

Field of study: Biology, Psychology
Stable carbon and oxygen isotopic evidence for Late Cenozoic environmental change in Northern China

Stable carbon and oxygen isotope ratios of 311 enamel samples from a diverse group of herbivorous mammals including Equidae, Rhinocerotidae, Bovidae, Rodentia and Ochotonidaewere were analyzed in order to reconstruct the Late Cenozoic history of vegetation and environmental change in the Yushe Basin in North China. The δ13C values of bulk and serial enamel samples from large mammals show a wide range of variation from − 13.3‰ to 1.4‰, with a mean of − 7.4‰ ± 3.5‰ (n = 294). This indicates that large herbivorous mammals in the area had a variety of diets since 6.5 Ma, ranging from pure C3 to mixed C3–C4 and pure C4 diets. In contrast, the δ13C values of small mammals vary from − 11.9‰ to − 7.6‰, with a mean of − 9.7 ± 1.1‰ (n = 17), indicating that rodents and ochotonids were feeding mostly on C3 plants. Variations in δ13C values within and between species reflect the variations in the habitat and the vegetation consumed by the animals. In general, horses had higher amounts of C4 grasses in their diets than other contemporary taxa such as bovids, rhinos, rodents and deer, suggesting that horses exploited more open habitats such as grasslands while deer, rhinos and rodents may have preferred more C3 vegetation, which is more indicative of forested environments. The carbon isotope data show that C4 grasses have been an important component of horses' diets and of local ecosystems since ~ 6.5 Ma, confirming that the “late Miocene C4 expansion” occurred in North China as it did in Africa, Indian subcontinent and the Americas. This supports a global factor as a main driver of the late Miocene C4 expansion. The combined carbon and oxygen isotope data reveal major shifts in climate to drier and/or warmer conditions after ~ 5.8, ~ 4.1, ~ 3.3, and ~ 2.5 Ma, and significant shifts to relatively wetter and/or cooler conditions after ~ 6.4, ~ 5, ~ 3.5 Ma. The shifts to drier and/or warmer climate after ~ 5.8 Ma and ~ 2.5 Ma coincide with two major fauna turnover events. Intra-tooth δ13C and δ18O values are negatively correlated within individual modern teeth and some fossil teeth, displaying the characteristic pattern of the summer monsoon regime and confirming a strong monsoon influence in the area since at least the early Pliocene. The data also suggest that the C4 abundance in the area has fluctuated over the past 6.5 Ma in response to changes in climate, with more C4 grasses during warmer and/or drier periods and a reduced C4 component at cooler and/or wetter times.

Field of study: Environmental science, Geography
Mechanisms of Neutrophil Transmigration Across Renal Proximal Tubular HK-2 Cells

Adhesion of intratubular leukocytes to proximal tubules in biopsies of patients with rapidly progressive glomerulonephritis and the appearance of leukocytes in the urine in interstitial nephritis suggest interactions between leukocytes and tubular epithelia in renal diseases. The aim of this study was to investigate the effect of cytokines and endotoxin on leukocyte migration through proximal tubular epithelial cells and also to determine the role of the transmembrane adhesion molecules ICAM-1 and CD47 in this process.  Experiments determined transepithelial migration (TEM) of PMN (polymorphonuclear) leukocytes through monolayers of HK-2. Expression of ICAM-1 and CD47 was assessed via confocal immunofluorescence, FACS analysis and western blotting. The effect of antibodies against ICAM-1 and CD47 on TEM was examined. Furthermore measurements of cytokine release (IL- 6 and IL-8) were performed.  Preincubation of HK-2 cells with either TNFα or LPS resulted in stimulation of PMN migration through monolayers of HK-2 cells. There was no preferred direction of transmigration. ICAM-1 was expressed by HK-2 cells and expression was increased after 4 h stimulation with TNFα or LPS. Application of ICAM-1 antibodies inhibited TEM. CD47 was expressed in both HK-2 cells and PMN. CD47 antibodies inhibited predominantly basolateral-to-apical TEM. HK-2 cells released IL-8 and IL-6 preferably into the apical compartment. Additionally, we showed that fMLP induced transmigration through monolayers of HK-2 cells was associated with significant increased CD47 expression on PMN cell surfaces.  Inflammatory mediators stimulate TEM of PMN through monolayers of HK-2 cells without a clearly discernible preference of direction. Mechanisms involved in TEM stimulated by cytokines or endotoxin appear to be mainly changes in surface receptor densities of HK-2 cells with ICAM-1 and CD47 playing an essential role.

Field of study: Biology, Chemistry
Food-avoidance in hungry pigeons, and other perplexities.

Twenty-three pigeons were subjected to a series of procedures in which the key-peck's effects ranged from immediate, differential food reinforcement, through delayed reinforcement, the production of stimulus changes with and without probable secondary reinforcement, the prevention of food presentation ("food-avoidance"), to extinction. Neither primary nor secondary food reinforcement appeared to be essential for the maintenance or acquisition of key pecking. The food-avoidance contingency failed to suppress responding in any subject. Only complete extinction, when pecking produced neither food nor stimulus changes, eliminated all pecking for most subjects. A combination of stimulus-change reinforcement and food reinforcement appeared to account for the results, but only if it could be assumed that the presence of food in a procedure enhanced the reinforcing power of stimulus change, whether or not the food was also dependent upon responding. Such an interaction between reinforcers may be involved in the phenomenon of autoshaping.

Field of study: Biology, Psychology
T and B cell responses following immunization with tetanus toxoid in IgA nephropathy

The B and T cell responses were investigated in IgA nephropathy before and after immunization with tetanus toxoid (TT). Both IgA and IgG anti‐tetanus toxoid antibodies were elicited, but the IgA ntibodies were significantly greater in patients (92·6 ± 11·7 ELISA units) than in the controls (49·2 ± 7·5 ELISA units). This was associated with a significantly greater proportion of IgA+ B cells in patients than controls before immunization. However, a significant increase in the proportion of IgA 1 binding CD4 and CD8 cells was also found. The proportion of CD3 cells with γδ T cell receptors (CD3+TCRγδ+), was significantly greater before immunization in the IgA nephropathy patients 37·0%± 2·4), compared with controls (100%± 2·3; P < 0·001). Immunization with TT further enhanced the CD3+TCRγδ5+ cells in patients to 45·8%± 7·2 compared with controls (16·3%± 4·5), with a corresponding decrease in CD3+TCRαβ+ cells in the patients (P < 0·001). CD3+TCRγδ+ cells are upregulated by common microbial antigens and clinical exacerbations of IgA nephropathy are frequently associated with mucosal infections and a rise in serum IgA concentration. The increased TCRγδ (5 expression may be responsible for the enhanced IgA antibody response in IgA nephropathy. The increase in IgA antibodies may then exert a controlling effect by binding to augmenting T cells and thereby inhibiting their function.

Field of study: Biology, Medicine
Effects under Different Liquid Culture Conditions on Morphology and Exo-polysaccharide of Acremonium implicatum

In the paper, the liquid culture of Acremonium implicatum was studied by means of different sucrose concentrations and nitrogen sources. The results showed that different nitrogen sources all had obvious effects on the morphologies of the mycelia. When peptone and soybean powder were of nitrogen sources, the diameter of mycelium was thicker and the conidia, in shape of oval, long oval or oblong, wider than that of NH_4NO_3, under which having fusiform conidia. Meanwhile, many conidia, some of them with long germ tubes, could be observed when soybean powder was used as nitrogen source. The effects of different concentrations of sucrose on the mycelial morphology was not obvious, but the exo-polysaccharides yield was significant. In addition, the effect of different nitrogen sources on the mycelial biomass was significant.

Field of study: Agricultural and Food sciences
Study of the tautomerism of 4- and 2- carbalkoxy-3-thiophanones

The equilibrium positions of 4-carbomethoxy-3-thiophanone (I), 2-carbomethoxy-4-methyl-3-thiophanone (II), 4,5-dicarbomethoxy-3-thiophanone (III), and 4-carbethoxy-5-phenyl-3-thiophanone (IV) in acetonitrile, dioxane, and alcohols was determined. The Meyer equation is satisfied for ketones I and II paired with acetylacetone and for III and IV paired with methyl cyclopentanone-2-carboxylate in alcohol solutions.

Field of study: Chemistry
Tasselia ordamensis: A biogenic structure of probable deposit-feeding and gardening maldanid polychaetes

The internal structure and growth direction of well-preserved Tasselia ordamensis specimens from the Upper Cretaceous–Cenozoic of Antarctica and Tierra del Fuego are not compatible with its current interpretation as a domichnion/equilibrichnium trace fossil. Accordingly, its functional morphology and the likely ethology of the producer are revised. Tasselia is a protrusive structure composed of a lined inner tube surrounded by vertically stacked sediment disks and ending in a basal chamber. Each disk has two domains of active burrow fills. The micritic, outer burrow fill domain consists of radial petaloid elements containing abundant radiolaria, calcispherules, diatoms and plant debris. This domain was formed by excavation due to deposit feeding; thereby non-ingested particles remained in the chamber and ingested particles passed through the gut to the sediment surface. Microfossil-rich material was collected at the sediment surface, placed in the feeding chamber, and rearranged within the petaloid elements probably after pulsed delivery of organic matter. The wineglass-shaped inner burrow fill domain is enriched in coarser particles and its petaloid elements crosscut the outer burrow fill domain. This domain probably functioned as “culturing compartment” for bacteria and its secondary reworking implies some form of ‘gardening’ and feeding on these bacterial populations at depth. The concentric striae on the organic-lined inner tube and the vertically stacked series of sediment-disks suggest maldanid polychaetes as the producers of T. ordamensis.

Field of study: Environmental science, Geography
Mood, Memory, and Vigilance: The Influence of Distraction on Recall and Impression Formation

This research investigated the influence of distraction on subjects' impressions and memory while in positive and negative moods. Subjects' incidental memory for affective traits used as a basis for forming an impression of a target person was assessed. Results indicated that subjects in negative moods were not as vulnerable to the influence of distraction on stimulus encoding as subjects in positive moods. In addition, mood effects on memory were observed but not on subjects' impressions. Results are interpreted using Schwarz and Clore's feelings as information model.

Field of study: Psychology