nils-herrmann/clean_scirepeval huggingface dataset:
Plant species diversity changes in abandoned chestnut (Castanea sativa) groves in southern France

Over the last few decades, marked land use changes have taken place in many Mediterranean ecosystems. For example, many chestnut groves in France are now abandoned and have turned into 'natural' coppice stands while others are now clear-cut every 10 or 15 years for wood. Species composition and life form diversity of the plant communities have changed markedly both in the abandoned groves and in the periodically clear-cut coppice stands. What are the consequences of these changes on biodiversity at local and regional scales, and what are the implications for 'new forestry' management intended to conserve biodiversity at the same time as it optimizes productivity and profitability? To answer these questions we studied plant species diversity in the understorey strata along a successional gradient including cultivated grove; abandoned grove; young (15 years old), medium (40 years), and old (>55 years) coppice stands. The results showed that species richness decreased quickly but not steadily along this gradient, but life-form spectra data highlighted that the high levels of plant species biodiversity in cultivated groves were due primarily to the large number of therophytes (annual plants). At a shorter time scale, we also studied the consequences of experimental clear-cutting on plant species biodiversity. Direct measurements over four years showed that species richness and diversity in the understorey increased in the first two years after clear-cutting, but decreased during the 3rd and 4th years. This decrease corresponded closely with a steady increase in Leaf Area Index of the forest canopy. These results have been used to suggest some possible ways to manage the biodiversity in these ecosystems.

Field of study: Environmental science
幽门螺杆菌BabA2/UreI融合基因表达质粒的构建

幽门螺杆菌(Helicobacter pylori,Hp)疫苗被认为是控制Hp感染有效的方法之一.本研究联合应用Hp BabA2和UreI基因作为构建HpDNA疫苗的目的基因,成功构建了pcDNA3.1/BabA2/UreI真核表达质粒。

Field of study: Biology
Primary attempt for simulating feedback system of low frequency

In order to improve the accumulation of the injected beam, it is necessary to restrain β oscillation caused by injected system error. This thesis systematically introduces the research of injection beam instability, the design principle and circuit of the feedback system for restraining the injected β oscillation of HLS using the turn by turn system. Meanwhile, it also provides the result of preliminary experiments. A relatively simple analog filter and phase shifter is used to counteract the β oscillation caused in kicker course. From experiment result, it is of obvious restraining effect. All of these are helpful for further development of feedback system of bunch-by-bunch and lower frequency in the future, and of the research of vertical and horizontal instability of beam.

Field of study: Physics
CD95-Dependent T-Cell Killing by Glioma Cells Expressing CD95 Ligand: More on Tumor Immune Escape, the CD95 Counterattack, and the Immune Privilege of the Brain

Apparent failure of tumor-infiltrating lymphocytes to induce significant tumor cell death has been documented in numerous malignancies including malignant gliomas. T-cell suppression in glioma patients has commonly been attributed to soluble immunosuppressive factors such as transforming growth factor-β (TGF-β). However, more recently CD95 ligand expressed on tumor cells has also been shown to induce T-cell apoptosis. Here, we report that human malignant glioma cells express CD95 ligand and kill human Jurkat T cells via CD95/ CD95 ligand interactions. T-cell apoptosis is blocked when interactions of CD95 ligand expressed on glioma cells with CD95 expressed on T cells are inhibited competitively by soluble CD95 protein. Although glioma cells coexpress CD95 ligand and CD95 and are highly sensitive to CD95 antibody or soluble CD95 ligand, they neither commit suicide nor fratricide. We conclude that (i) susceptibility to CD95-mediated apoptosis involves crucial regulatory mechanisms other than levels of CD95 and CD95 ligand expression, and (ii) multiple mechanisms including soluble factors such as TGF-β and cell-derived signals such as CD95 ligand-induced signalling mediate immune escape of malignant brain tumors.

Field of study: Biology, Chemistry
Broad line quantitative chemical shift spectroscopy.

Proton NMR spectroscopy was applied to quantitate the measurement of total body water/fat distributions in vivo. A special MR protocol was developed to excite a thick slab of tissue and display the magnitude NMR spectrum of the collected response signal. Very short echo time TE (8 ms) and long repetition time TR (4000 ms) were used to minimize relaxation damping of the signal intensities. The spectrum was then decomposed into individual lines and proton densities of different species were calculated. Proton density information was converted into weight percentage data using stoichiometrical and physiological information. The technique was validated using phantoms that contained different mixtures of water/maize oil. A high-resolution NMR spectrum of maize oil samples was used to determine the stoichiometric information. The test results showed good agreement with the known composition of the phantom within the whole range of water content (0-100%). This method is very fast since no phase encoding of data is required. Preliminary results for monkeys show promising potential in clinical applications.

Field of study: Medicine, Physics
Anatomy involved in the jugular foramen approach for jugulotympanic paraganglioma resection.

The goal in paraganglioma resection is to allow adequate exposure to remove the lesion while preserving cranial nerve function. Knowledge of the anatomy of the jugular foramen is crucial to this endeavor. In this report the authors describe a jugular foramen approach for the resection of glomus jugulare tumors in cases in which rerouting of the facial nerve can be avoided. This approach provides adequate exposure of the jugular bulb for many jugulotympanic paragangliomas without increased risk of injury to the facial nerve. In addition, special circumstances surrounding intracranial and carotid artery involvement are briefly discussed.

Field of study: Medicine
The Motivation to Teach

This article examines the relationships between important needs of faculty and the processes and contexts of teaching in institutions of higher learning that might affect need satisfaction. The theme of the paper is that the ineffability of the goals and effects of teaching, the ambiguities in the social context of teaching, and the difficulties in measuring success serve to block satisfactions of faculty and force them to turn to other pursuits which seem be be more rewarding.

Field of study: Education
Optimum exponential regression with one nonlinear term

A method is suggested for estimating regression parameters for a model E(Y = a + bX + ce^-^@?^t, where observations on Y, X and t are given. This model has been extensively used in economics for relating optimum output of a production process with the available labor and services. This method is optimum in the sense it involves minimizing the error sum of squares for the linear regression of Y on X and e^-^@?^t over the range @?>0. The limits as @? -> 0 and @? -> ~ are obtained and the computational procedure is discussed.

Field of study: Mathematics
The Causal Role of Theories of Relationships: Consequences for Satisfaction and Cognitive Strategies

Two studies demonstrated the causal role of relationship theories in influencing relationship satisfaction and the processes affecting satisfaction. In both studies, participants were induced to hold either the soulmate or work-it-out theory. Feelings that one’s partner was ideal (or not) were associated with relationship satisfaction more strongly for people induced to hold the soulmate theory than the work-it-out theory (Study 1). In Study 2, participants’ beliefs about their relationships were threatened, and strategies for responding to this threat were assessed. Inducing people to hold the soulmate theory resulted in more relationship-enhancing cognitions if participants believed they were with the right person but more relationship-detracting cognitions if participants did not believe they were with the right person. These polarizing tendencies were enhanced under threat. In contrast, inducing people to hold a work-it-out theory produced almost no biased processing, leading people to process information similarly, regardless of their feelings about their partner.

Field of study: Psychology
Wavefront reversal of focused beams (theory of stimulated Brillouin backscattering)

An analysis is made of wavefront reversal (WFR) in stimulated scattering of a pump beam with small-scale inhomogeneities, focused in a medium unbounded along the transverse coordinate. The solution is sought in the form of a pump-reversing wave with a continuously varying envelope. Allowance is also made for corrections for small-scale distortions correlated with the gradients of the pump field. An equation for the envelope derived previously by the authors is solved for the case of excitation of stimulated scattering from spontaneous noise. Hermite–Gaussian "modes" of this equation are found. The main conclusion from the solutions is that WFR in stimulated scattering of focused beams neglecting the influence of the scattered field on the pump wave not only results in narrowing of the WFR wave envelope but also in the formation of smallscale distortions which increase with distance from the beam axis. An analysis is also made of amplification of Stokes waves uncorrelated with the pump wave.

Field of study: Engineering, Physics
Carbon isotope (δ13Ccarb) stratigraphy of the Lower–Middle Ordovician (Tremadocian–Darriwilian) in the Great Basin, western United States: Implications for global correlation

New stable carbon isotope data (δ13Ccarb) from Lower–Middle Ordovician (Tremadocian to Darriwilian) carbonate mudstone and wackestone rocks of the Pogonip Group are presented from two sections in the Great Basin region (USA) — Shingle Pass (east-central Nevada) and the Ibex area (western Utah). The Pogonip Group is a succession of mixed carbonate and siliciclastic rocks that accumulated on a carbonate ramp under normal marine conditions during the Late Cambrian (Furongian) to Middle Ordovician (Darriwilian). The Shingle Pass and Ibex area sections have been previously studied for their conodont biostratigraphy and contain a North American Midcontinent conodont fauna that range from the Cordylodus intermedius Zone (uppermost Cambrian) to the Phragmodus polonicus Zone (Darriwilian). The δ13C trend has four distinct characteristics recognized in both Great Basin sections: 1) a drop in δ13C from + 1‰ at the base of the Ordovician (Tremadocian) to − 0.7‰, 2) a 1 to 2‰ positive δ13C shift in the uppermost Rossodus manitouensis Zone during the late Tremadocian, 3) a gradual δ13C increase from − 2‰ to ca. 0‰ during the end of the Early Ordovician (Floian), and 4) a steady δ13C decrease from 0‰ to − 4 to − 5‰ during Middle Ordovician (Dapingian–Darriwilian). In the Lower Ordovician, δ13C trends reported here from the Great Basin are not consistent with a causal mechanism involving sea level change and the migration of isotopically distinct water bodies. Instead, these Lower Ordovician isotope data most likely reflect primary seawater chemistry and changes in δ13C on a global scale. This interpretation is supported by the excellent correlation of δ13C in the Lower Ordovician to other δ13C trends reported from the sections in the Argentine Precordillera (La Silla and San Juan formations) and in western Newfoundland (St. George and Table Head groups). These correlations using δ13C are consistent with published biostratigraphic data and provide an integrated and high-resolution chemo-biostratigraphic framework for the Lower Ordovician sedimentary record of the Laurentian margin. The Middle Ordovician portion of the δ13C curves in the Great Basin represented by the Kanosh and Lehman formations shows significant isotopic depletion relative to the section in Argentina. Thus, although there is some indication that minima and maxima in the Middle Ordovician curves can be correlated, the Great Basin sections show clear evidence of overprinting by local variables related to both diagenesis (dolomitization) and platform restriction.

Field of study: Environmental science, Geography
Temperature dependence of the Fermi level in the two-zone hybrid model of doped semiconductors

On the basis of the two-zone hybrid model of doped semiconductors suggested earlier  (1989)) have analysed the behaviour of the Fermi level and the degree of ionisation of the impurity band over a wide temperature range. The calculation of the density of states is performed using a modified Matsubara-Toyozawa method (1960) in which the so-called multiple occupancy corrections are fully taken into account. The results obtained are compared with the corresponding ones of a simpler delta model which is a good approximation of the well known Kane and Morgan density of states relations.

Field of study: Materials science
Probing unconventional superconductivity using the field dependent magnetic penetration depth

The temperature dependence of the magnetic penetration depth $\lambda$ has been widely used to investigate the momentum space structure of the superconducting energy gap, in-particular whether it has nodes or not. Here we show that the magnetic field dependence of $\lambda$ is strongly enhanced in low-$T_c$ unconventional superconductors and that $\lambda(T,H)$ can be used to distinguish nodal pairing states from those where there is a small residual gap, which in the presence of small amounts of disorder are difficult to differentiate using $\lambda(T)$ alone. We show data for CeCoIn$_5$ and LaFePO which are consistent with a nodal gap and for KFe$_2$As$_2$ where the non-linear response is dominated by a small but finite gap.

Field of study: Physics
Establishing Virtual Circuits in Large Computer Networks

Network routing algorithms generally attempt to provide communication between two nodes by sending data messages along the best or shortest path between them. Unfortunately, in large networks it is difficult to maintain knowledge of such path due to the cost in storage, computation, and communication bandwidth. In an attempt to solve this problem the technique of clustering has been proposed. Clustering generally reduces the cost of routing of by sacrificing optimality. Kamoun has shown that this sacrifice is asymptotically negligible under certain strong assumptions. In this paper we propose a new clustering technique which permits us to obtain optimal paths. However, determining these paths requires some effort and thus the methodology is appropriate only if the paths are then used for many messages in virtual circuit fashion. An application to planar networks gives a quantitative demonstration of obtaining optimal paths with reduced path determination cost.

Field of study: Computer science
Nonparametric regression method with functional covariates and multivariate response

Nonparametric regression methods have been widely studied in functional regression analysis in the context of functional covariates and univariate response, but it is not the case for functional covariates with multivariate response. In this paper, we present two new solutions for the latter problem: the first is to directly extend the nonparametric method for univariate response to multivariate response, and in the second, the correlation among different responses is incorporated into the model. The asymptotic properties of the estimators are studied, and the effectiveness of the proposed methods is demonstrated through several simulation studies and a real data example.

Field of study: Mathematics
Solubilities of terephthalic acid in amides solvents

Experimental solubilities of terephthalic acid(TA) dissolved in N,N-dimethyl propionamide(DMP),N,N-diethyl propionamide(DEP) and N,N-diethyl acetamide(DEA) were determined in the temperature range of 303.2—363.2 K.The experimental results showed that the solubility of TA increased significantly with an increase in temperature and had different temperature sensitivities in different solvents.The solubility data were correlated by Buchowski equation,and the parameters h and λ were regressed,which gave good agreement with all experimental data.

Field of study: Chemistry, Environmental science
The links between magnetic fields and filamentary clouds – III. Field-regulated mass cumulative functions

During the past decade the dynamical importance of magnetic fields in molecular clouds has been increasingly recognized, as observational evidence has accumulated. However, how a magnetic field affect star formation is still unclear. Typical star formation models still treat a magnetic fields as an isotropic pressure, ignoring the fundamental property of dynamically important magnetic fields: their direction. This study builds on our previous work which demonstrated how the mean magnetic field orientation relative to the global cloud elongation can affect cloud fragmentation. After the linear mass distribution reported earlier, we show here that the mass cumulative function (MCF) of a cloud is also regulated by the field orientation. A cloud elongated closer to the field direction tends to have a shallower MCF, in other words, a higher portion of the gas in high density. The evidence is consistent with our understanding of bimodal star formation efficiency discovered earlier, which is also correlated with the field orientations.

Field of study: Physics
The effects of basolateral amygdala lesions on unblocking.

Prior reinforcement of a neutral stimulus often blocks subsequent conditioning of a new stimulus if a compound of the original and new cues is paired with the same reinforcer. However, if the value of the reinforcer is altered when the compound is presented, the new cue typically acquires conditioning, a result called unblocking. Blocking, unblocking, and related phenomena have been attributed to variations in processing of either the reinforcer, for example, the Rescorla-Wagner (1972) model, or cues, for example, the Pearce-Hall (1980) model. Here, we examined the effects of lesions of the basolateral amygdala on the occurrence of unblocking when the food reinforcer was increased in quantity at the time of introduction of the new cue. The lesions had no effects on unblocking in a simple design (Experiment 1), which did not distinguish between unblocking produced by variations in reward or cue processing. However, in a procedure that distinguished between unblocking due to direct conditioning by the added reinforcer, consistent with the Rescorla-Wagner (1972) model, and that due to increases in conditioning to the original reinforcer, consistent with the Pearce-Hall (1980) and other models of learning, the lesions prevented unblocking of the latter type. These results were discussed in the context of roles of the basolateral amygdala in coding and using reward prediction error information in associative learning.

Field of study: Biology, Psychology
Remarkable impact of grains boundaries on the chemical delithiation kinetics of LiFePO4

The kinetic of LiFePO 4 chemical delithiation was studied on sintered powders synthesized by precipitation method and partially oxidized using Br 2 in acetonitrile. Thorough X-ray diffraction analyses using Rietveld refinements revealed a two-phase reaction with a slight deviation of the lattice parameters. Coherency domains of the two end members were determined using the Thomson-Cox-Hasting function and they linearly increase for the lithium poor phase at the detriment of the lithium-rich phase. The HRSTEM-EELS measurements on partially delithiated samples validate the Shrinking Core mechanism with a core of LiFePO 4 surrounded by a shell of FePO 4. Thus, each particle undergoes a two-phased transformation. Furthermore, the HRSTEM-EELS reveals that the grain boundaries (resulting from the heat treatment in order to improve phase crystallinity) strongly hinder the delithiation kinetics. Chemical delithiation triggers agglomerates breaking and particle splitting at grain boundaries. This new aspect may provide information on the impact of microstructure on the electrochem-ical performances of LiFePO 4 materials.

Field of study: Materials science
Changes in the carbon cycle of Amazon ecosystems during the 2010 drought

Satellite remote sensing was combined with the NASA-CASA (Carnegie Ames Stanford Approach) carbon cycle simulation model to evaluate the impact of the 2010 drought (July through September) throughout tropical South America. Results indicated that net primary production in Amazon forest areas declined by an average of 7% in 2010 compared to 2008. This represented a loss of vegetation CO2 uptake and potential Amazon rainforest growth of nearly 0.5 Pg C in 2010. The largest overall decline in ecosystem carbon gains by land cover type was predicted for closed broadleaf forest areas of the Amazon river basin, including a large fraction of regularly flooded forest areas. Model results support the hypothesis that soil and dead wood carbon decomposition fluxes of CO2 to the atmosphere were elevated during the drought period of 2010 in periodically flooded forest areas, compared to those for forests outside the main river floodplains.

Field of study: Environmental science
Magmatic and metamorphic events during the early Paleozoic Wuyi-Yunkai orogeny, southeastern South China: New age constraints and pressure-temperature conditions

The early Paleozoic Wuyi-Yunkai orogen in South China is a major orogenic belt in East Asia that formed at a similar time as the classic Caledonian orogeny in Europe. Despite the possibility of its being one of the few examples of intraplate orogenesis in the world, details about the orogen remain poorly defined. In this study, we provide age constraints on metamorphic and magmatic events in the eastern segment of the orogen, and the protoliths of the amphibolite-facies metamorphic rocks found there. By combining previous work with our new metamorphic and petrogenetic analyses, we present the following findings: (1) the Wuyi-Yunkai orogeny occurred between mid-Ordovician (>460 Ma) and earliest Devonian (ca. 415 Ma) time; (2) amphibolite-facies metamorphism in the eastern Wuyi-Yunkai orogen occurred between ca. 460 and 445 Ma, whereas cooling below 500–300 °C occurred by ca. 420 Ma; (3) the orogen exhibits a clockwise pressure-temperature ( P - T ) path and a maximum pressure of >8 kbar, indicating crustal thickening during the orogeny; (4) protoliths of the high-grade metamorphic rocks in the eastern segment of the orogen were dominantly Neoproterozoic (840–720 Ma) volcanic and volcaniclastic rift successions and younger deposits formed in a failed rift, and Paleoproterozoic rocks account for only a small proportion of the outcrops; and (5) the analyzed granites indicate a mixed source of Paleoproterozoic basement and Neoproterozoic continental rift rocks, with elevated melt temperatures of >800 °C, which are interpreted as reflecting dehydration melting of basin sediments taken to below midcrustal levels.

Field of study: Geology