nils-herrmann/clean_scirepeval huggingface dataset:
SU-G-IeP1-11: Resting-State Fluctuation of BOLD Signal Amplitude for Mapping Cerebrovascular Reactivity in Presurgical Functional MRI.

Cerebrovascular reactivity (CVR) MRI with hypercapnia challenges, such as a breath-hold (BH) task, has been proposed to indicate areas with neurovascular uncoupling potentials for presurgical functional MRI (fMRI). This study aimed to explore the use of resting-state (RS) fMRI, in particular, the RS fluctuation of amplitude (RSFA) for detecting the impaired CVR and compare with BH MRI in patients with gliomas.



The BH and RS fMRI from six patients as part of their presurgical fMRI studies were analyzed. Functional images were coregistered to the 3D T1-weighted images and spatially smoothed using a 4-mm Gaussian kernel. A band-pass filter (0.01-0.08 Hz) was then applied to the RS time series. Temporal standard deviations of the BH and the filtered RS signal changes were computed for each voxel to indicate CVR and subsequently transformed to Z-scores. For quantitative comparison, a region of interest (ROI) with significant CVR in the sensorimotor cortex on the contralateral side of the tumor was determined for each patient as Z-scores greater than 50% of the local maxima. In addition, a tumor ROI was determined by referencing the T2 FLAIR and post-contrast T1-weighted images of each patient.



Significant cross-subject correlations between the BH CVR and RSFA were found in both the sensorimotor and tumor ROIs (r=0.59, p<0.05 and r=0.83, p<0.05, respectively). Within individuals, voxel-based analyses showed significant correlations between two methods in both ROIs in all patients. The spatial patterns of BH CVR and RSFA maps appeared similar across the brain with sparse local discrepancies.



The RSFA derived from RS-fMRI is a promising method for probing impaired CVR in presurgical fMRI mapping. Unlike BH, RS-fMRI is less dependent on patient performance. In addition, with its proven relation to neural activity, RSFA of certain frequency bands has potentials to better indicate the neurovascular uncoupling.

Field of study: Medicine, Physics
Use of humic acid solution to remove organic contaminants from hydrogeologic systems.

Experiments were carried out to evaluate the effectiveness of a 29 mg/L solution of humic acid to enhance the removal of six aromatic hydrocarbons (benzene, toluene, p-xylene, ethyltoluene, sec-butylbenzene, and tetramethylbenzene) from a sandy material. None of the compounds were completely removed from the material. Nonetheless, the compounds with the highest water solubility, benzene and toluene, were removed effectively; less than 1 mass % was retained with use of either the humic acid solution or water. For the less soluble organic compounds, removal was more difficult and was enhanced by the humic acid solution compared to water. Mass percent retained with humic acid was as follows: p-xylene, 1.4% (24% less than water); 3-ethyltoluene, 6.4% (40% less); sec-butylbenzene, 39% (14% less); and tetramethylbenzene, 43% (14% less). The positive effect of humic acid on the removal of these organics may arise from the aggregation of the humic acid molecules to form membranes and/or micelles, having hydrophilic exteriors and hydrophobic interiors. Partitioning of the hydrophobic organics from the bulk solution into the hydrophobic interior of these humic acid structures can account for their enhanced removal from the sandy material.

Field of study: Environmental science
Coexistence of Superconductivity and Magnetism in R2-xcexrusr2cu 2o10-? (R=Eu and Gd)

R2-xCexRuSr2Cu2O10-d(Ru-2122) is the first Cu-O based system in which superconductivity (SC) in the CuO2 planes and weak-ferromagnetism (W-FM) in the Ru sublattice coexists. The hole doping in the CuO2 planes, is controlled by appropriate variation of the Ce concentration and/or increasing the oxygen concentration. In Eu2-xCexRuSr2Cu2O10, SC occurs for Ce contents of 0.4-0.8, with the highest TC=35 K for Ce=0.6. The as-prepared non-SC EuCeRuSr2Cu2O10 sample exhibits magnetic irreversibility below Tirr=125 K and long range o anti-ferromagnetic (AFM) order at TM =165 K. The saturation moment at 5 K is Msat=0.89 mB /Ru. Annealing under oxygen pressures, does not affect these parameters, whereas depletion of oxygen shifts both Tirr and TM up to 169 and 215 K respectively. TM, Tirr and Msat decrease with x, and the Ce dependent magnetic-SC phase diagram is presented. A simple model for the SC and the long-range W-FM states is proposed. We argue that: (i) the system becomes AFM ordered at TM; (b) at Tirr < TM, W-FM is induced by the canting of the Ru moments, and (c), at lower temperatures the appropriate samples become SC at TC. The magnetic features are not affected by the SC state, and the two states coexist.

Field of study: Physics
Microclimate and fluxes of water vapour, sensible heat and carbon dioxide in structurally differing subalpine plant communities in the Central Caucasus

Effects of canopy structure on microclimate, energy budget and CO2 exchange were analysed in a pasture, two hay meadows, a tall herb community and a dwarf shrub community in the subalpine belt of the Central Caucasus. The results show that canopy structure exerts a marked influence on the distribution of photon flux density, temperature and canopy photosynthesis Ac. Three canopy types were distinguished. Type 1 (pasture) has a small LAI (leaf area index) and more than two-thirds of the phytomass is concentrated in the lowest few cm of the canopy, mainly as planophile leaves. This results in (1) a low degree of utilization of photosynthetic photon flux density (PPFD) by assimilatory plant components, (2) high leaf temperatures and a high soil heat flux during the phase of incoming radiation, and (3) a relatively low Ac/ LAI ratio. Type 2 (meadows), in spite of its erect leaves, which at high solar elevations permit light to penetrate to the lower canopy layers, is characterized by (1) marked effects of mutual shading in the lower canopy layers for most of the day, and thus (2) only slight variations in air and leaf temperatures and (3) a comparatively low Ac/LAI ratio. In canopies of type 3 (tall herb and dwarf shrub communities), there is a concentration of flat leaves in the upper layers. This results in (1) very good utilization of PPFD; (2) no strong fluctuations in canopy temperature as the flat leaves act as a buffer, reducing the amounts of incoming and outgoing radiation in lower canopy layers, and (3) high values of the Ac/LAI ratio. The energy budgets of the canopies investigated are governed not so much by their spatial structure, but rather indirectly by LAI and the degree of coupling of the canopy with the atmosphere.

Field of study: Environmental science
Phosphatidylcholine stimulates the activity of UDP-Gal beta 1-4 galactosyltransferase in normal human kidney proximal tumour cells.

Effects of various lipid components of low density lipoproteins (LDL) and serine on the regulation of UDP-Gal-beta 1-4-galactosyltransferase (GalT-2) activity have been investigated in normal proximal tubular (PT) cells. Addition of exogenous serine (0.1-0.75 mM), cholesterol (0-200 micrograms/ml medium), linoleic acid and oleic acid (0.1-0.75 mM) for 4 hr at 37 degrees C did not suppress the activity of GalT-2 in PT cells. Similarly, incubation of cells with glucosylceramide and lactosylceramide (25-50 micrograms/ml medium) did not alter GalT-2 activity in cells as compared to control. In contrast, palmitic acid (0-0.75 mM), phosphatidylethanolamine and sphingomyelin (0-200 micrograms/ml) stimulated GalT-2 activity by 20-36% as compared to control. Incubation of PT cells with D-alpha-dipalmitoyl phosphatidylcholine (0-200 micrograms/ml medium) also stimulated the activity of GalT-2, maximum stimulation (200%) occurring with 25 micrograms phosphatidylcholine/ml medium. However, at a higher concentration (200 micrograms/ml), the stimulation of the activity of GalT-2 was in the order of 27% compared to control. Dioleylphosphatidylcholine did not alter GalT-2 activity in PT cells. Thus, it is concluded that (i) various lipid components, sphingosine and serine present in LDL are not involved in the LDL-mediated suppression of GalT-2 activity in normal PT cells, and (ii) stringent structural requirements in the phosphatidylcholine molecule are necessary to exert a time and concentration dependent stimulation of GalT-2 activity.

Field of study: Biology, Chemistry, Physics
Timing of dialysis initiation: when to start? Which treatment?

During the late 1990s early initiation of dialysis was introduced on a large scale and between 1996 and 2008, the percentage of patients with an estimated glomerular filtration rate (eGFR) above 10 mL/minute starting dialysis rose from 25% to 54% in the United States. However, several subsequent studies showed no survival benefit for patients commencing dialysis earlier. One possible explanation for the negative results could be that eGFR may be a flawed index; s-creatinine is lower in patients with muscle wasting or fluid overload and these vulnerable patients with high comorbidity burden often start "early", i.e., at higher eGFR. Another explanation could be that dialysis is in fact harmful; dialysis initiation with conventional thrice weekly in-center hemodialysis clearly associates with increased initial mortality risk especially when using temporary dialysis catheters. Interestingly, patients starting on peritoneal dialysis (PD) appear to have better initial outcomes. More attention should be given to finding new objective mortality-predictive markers of uremia, reducing the use of temporary hemodialysis catheters, and increasing the use of PD as initial dialysis modality. PD may not only provide better initial dialysis outcomes but may also preserve renal function and vessels for vascular access for the benefit of better long-term outcomes.

Field of study: Medicine
Unsignalled delay of reinforcement in variable-interval schedules.

Three pigeons responded on several tandem variable-interval fixed-time schedules in which the value of the fixed-time component was varied to assess the effects of different unsignalled delays of reinforcement. Actual (obtained) delays between the last key peck in an interval and reinforcement were consistently shorter than the nominal (programmed) delay. When nominal delays were relatively short, response rates were higher during the delay condition than during the corresponding nondelay condition. At longer nominal delay intervals, response rates decreased monotonically with increasing delays. The results were consistent with those obtained from delay-of-reinforcement procedures that impose either a stimulus change (signal) or a no-response requirement during the delay interval.

Field of study: Biology, Psychology
On the dilemmas in the traditional Chinese national sports games system.

The Traditional National Games has a lot of deficiencies and defects in terms of system and mode: it adopts the organization mode used by competitive sports games,thus resulting in the occurrence of championism,the dissimilation of events and the existence of rule flaws;it adopts event classifying rules without scientific grounds,thus resulting in event development going toward two extremes–the events become artistic and competitive;it has a vague conception about event selection,thus resulting in its failure to develop in a diversified way.

Field of study: Education
Race, State, and Armed Forces in Independence-Era Brazil: Bahia, 1790s-1840s (review)

Armies not only played a critical role in the wars of independence in Latin America, but also had a great impact upon the political structure of post-independence republics. Yet, since Brazil took a different path to nationhood than did its Spanish American neighbors, there has been a lack of serious studies on the transformation of a colonial Portuguese establishment into a national institution. Hendrik Kraay's path-breaking work on the Bahian military has repaired this deficiency.

Field of study: History
A Note on “Behavioral Limits”

The purpose of this methodological note is to emphasize that an experimental psychologist is often implicitly interested in behavior in some fixed condition as the limit of behavior in a sequence of conditions and to assert that it is possible to design experiments with this as a goal. When a psychologist fits a function or develops a theoretical function to describe a set of points, any point included, and in particular the end points, can be looked upon as achieving much of their significance from the values of the sequence of points "approaching" them. Such a purpose can, however, be more explicitly incorporated. Behavior in a sequence of conditions can be expressly used to interpret the behavior in, o r isolate the variables necessary to predict the behavior in, a "limiting" condition of particular interest. In this way, behavior at a fixed value of a variable may be studied (and implicitly is studied) in much the same way mathematicians found it useful to study the behavior of a function at a point. A cause of some difficulties is thar the original source of many experimental paradigms currently used in experimental psychology is experimental agriculture. Along with statistical methods, e.g., the analysis of variance, which infiltrated psychology were some extra statistical influences which have acted essentially as restraints against explicitly interpreting the resulcs at one point in terms of the results for other values of a variable. These restraints have often resulted in an even distribution of interest over the range of variables, but in experimental psychology, there is no strong analogy to evenly divided plots of ground. Even counterbalancing methods which rely implicitly upon this analogy also impose restrainrs on concenrrating interest at a particular point. It therefore appears that as experimental psychology becomes more interested in finegrained relationships, such restraints in the design of experiments must be avoided. Some investigation of behavioral limits, which represent an extreme in concentration of interest, can be conducted within existing experimental paradigms. In an experiment by McConnell and Shelly (1960) an effort was made to obtain some insights into continuous tracking behavior through examining how behavior changed on a series of discrete tracking problems which approached the continuous case. Here it was found thar the same method ( a linear relationship on amplitude of step inputs) could be used for predicting tracking performance on two quite different continuous tasks, thus showing that they, as limits of similar sequences of conditions, had more similar properties than their apparent dissimilarity indicates. The benefits which accrue from this type of study will, however, never be fully exploited without the development of statistical methods explicitly designed to treat certain results as behavioral limits.

Field of study: Psychology
Contextually incomplete descriptions – a new counterexample to Russell?

to have assumed that an utterance will be unintelligible if it does not (or could not, in the circumstances, be expected to) convey a proposition. I have argued that this assumption is false I put forward (la) as a counterexample. I propose a related assumption in its place: that an utterance will be unintelligible if it neither expresses nor conveys a proposition. Not only is this assumption more plausible, in my view, it also underwrites my objection against RTD. I may not have shown, as Bach invites me to, that the difference in intelligibility between utterances involving CIDs and their Russellian paraphrases reflects a difference at the semantic level. In a sense, I have just assumed it! But I trust readers will find this assumption has more going for it than alternatives Russellians may resort

Field of study: Philosophy
BIFURCATION AND CHAOS IN TWO SIDES SIMPLY SUPPORTED AND TWO SIDES FIXED THIN RECTANGULAR PLATE UNDER TRANSVERSE ELECTROMAGNETIC FIELDS

The problem of bifurcation and chaos in a thin rectangular plate under the electromagnetic fields and mechanic fields were studied. Base on nonlinear electro-magneto-elastic equations of thin rectangular plate under transverse electromagnetic fields and transverse loads, the vibration equations of two sides simply supported and two sides fixed thin rectangular plate were obtained The chaotic criterion of this system was obtained by Melnikov function method, and the vibration equation of the system was solved using numerical value method. And in the specific examples, the bifurcation diagram, the exponent Lyapunov diagram, the wave diagram of displacement, phase diagram and Poincare map were derived. The influences of magnetic parameter and mechanic loads on the vibration of the system were analyzed.

Field of study: Engineering
Incidental Intracranial Aneurysms: September 2002

This month's issue of Neurosurgical Focus concentrates on the management of intracranial aneurysms. The authors of the lead article review risk factors for postprocedure morbidity after treatment of incidental intracranial aneurysms. The findings in this manuscript document that incidental intracranial aneurysms may be treated and result in less morbidity than noted in the International Study of Unruptured Intracranial Aneurysms (ISUIA) report. The current study reviews a single group's experience with the management of intracranial aneurysms, taking a comprehensive team approach to the management of these lesions. Thus, it cannot easily be correlated with the ISUIA trial. The main finding of this study suggests that surgical management may involve a morbidity rate as high as reported in the ISUIA trial. The significant findings in this paper are that aneurysms greater than 13 mm in size and those with broad and calcified necks portend a greater risk for surgical morbidity. In the past, familial predisposition toward cerebral aneurysms has always been described in patients with two or more affected family members. The second manuscript in this issue suggests that first-degree relatives of patients with aneurysms are at higher risk for harboring intracranial aneurysms. The authors analyzed 96 relatives between the ages of 20 and 70 years with three-dimensional fast–spin echo magnetic resonance imaging for the presence of intracranial aneurysms. They found that the incidence of unruptured aneurysms was greater than anticipated. Given the noninvasive means available for evaluating patients, it may be of benefit to have all relatives undergo three-dimensional magnetic resonance imaging. The focus of the final vascular paper is on a single group's experience using the subtemporal approach for the management of basilar bifurcation aneurysms. The authors describe their modifications and technical nuances. This is a superb technical note from a group with considerable experience. This issue focuses on some of the finer details of intracranial aneurysm disease. The reader should gain a greater understanding of the management of patients with unruptured intracranial aneurysms and their first-degree relatives. Moreover, the technical surgical approach for basilar bifurcation aneurysms is superbly reviewed.

Field of study: Medicine
Dietary and inhalation exposure to polycyclic aromatic hydrocarbons and urinary excretion of monohydroxy metabolites--a controlled case study in Beijing, China.

Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs.

Field of study: Environmental science
[The optimization of the late-life depression assessment scale and recommendations for its practical use].

The authors elaborated earlier the late-life depression assessment scale (version 1.0) which proved to be effective for the diagnosis and description of the structure and severity of depression in elderly patients. In this paper, they have improved this scale by adding corrections in the scale structure and dimensionality of assessment items. The retrospective analysis of primary symptoms assessed by the scale revealed that items with negative scores reflected the signs of the psychorganic syndrome and are not associated with the psychopathology of depression. The exclusion of these symptoms allow to shorten the scale and to use the same dimensionality to make it easier to use the scale in clinical and research practice. A trial of the new version (1.2) of the scale indicated its diagnostic effectiveness and the ability to measure correctly the depression's severity and changes in the status of elderly patients.

Field of study: Medicine, Psychology
Simultaneous determination of 11 organic acids in concentrated juices using SPE-reverse-phase high performance liquid chromatography

A method was developed for the determination of the tartaric acid,quinic acid,malic acid,shikimic acid,Vc,acetic acid,maleic acid,lactic acid,succinic acid,fumaric acid and citric acid in juices using reversephase high performance liquid chromatography.The sample was diluted by water and then was purified by C18 solid-phase extraction(SPE).Reverse-phase liquid chromatographic analysis was performed on the instrument of Agilent 1100 series equipped with a diodearray detector and autosampler.The column was Aichrom BondAQ C18(25 cm×4.6 mm,5 μm).The mobile phase was 0.02 mol/L NH4H2PO4(pH2.8)-Methanol(99:1,v/v) with a flow rate of 0.8 mL/min.The detection wavelength was 210 nm.The retention time for all of organic acids in the pear,apple,strawberry and pomegranate juices were less than 15 min after the samples treated by SPE.The calibration curve for the organic acids was in good linearity with a correlation coefficient of upwards 0.990.The recovery ratio of the organic acids was 85.1%~95.5% and the coefficient of variation was less 4%.The results indicate that this method is handy,fast,veracious and practical for the routine analysis of organic acids in juices.

Field of study: Agricultural and Food sciences