julilili42/papers huggingface dataset:
Void Evolution in Soluble Rocks Beneath Dams Under Limited Flow Condition
2005-09-22

In this study, the numerical model CAVE (Carbonate Aquifer Void Evolution) was used to simulate the development of solution conduits beneath a weir that is constructed on river sediments overlying gypsum bedrock. The weir site is located at Hessigheim on the Neckar River in the State of Baden-Württemberg, Germany. After flowing through the State of Baden-Württemberg over a length of 367 km, the Neckar flows into the Rhine River near Mannheim and Heidelberg. At this site, a non-soluble layer overlying soluble rock limits the maximum leakage from the reservoir. The model was used to identify the key parameters controlling void evolution under flow conditions controlled by soluble and non-soluble rocks. In all, three scenarios were simulated. Sensitivity analyses indicate that the breakthrough time was influenced by permeability of the stratigraphic units, initial conduit diameter, conduit length and the number of nodes coupled to the gypsum layer. Leakage rates of the order of 10–7 m3 s–1 (about 9 L day –1) were observed after breakthrough for the standard scenario. Thus, under limited flow conditions, if the hydraulic conductivity of the intervening layer is sufficiently low, leakage rates may not pose a serious threat to the dam's ability to store water. However, the development of conduits having diameters of the order of tens of centimeters or more may pose a threat to the long-term physical stability of the dam.
Environmental Isotope Study on Recharge and Groundwater Residence Time in a covered Ordovician Carbonate Rock
2005-09-22

This paper applies environmental isotope techniques to interpret recharge mechanisms and estimate transit time of a covered karst aquifer in semiarid NW China. The aquifer is of major importance to the water supply of the region, in particular in meeting the increasing demand on water resources and in sustainability assessment in the future. Deuterium, oxygen-18 and tritium of 459 samples were analyzed from precipitation, surface water and groundwater during one hydrological year. Based on the isotope analysis, the Ordovician carbonate recharge to the aquifer is mainly from direct infiltration of atmospheric water in carbonate outcrops in Sandao and the Dacha valley. Stable isotopes show that karst groundwater in the Dacha valley seems to have recharged in a catchment area with a mean elevation of 1685–1854 m. The distinct independent isotope composition of water in the limestone aquifer in the Dacha valley from that in Anguo suggests no interconnection between them. However, the temporal evolution of the stable isotopes concentrations, the tritium contents and the hydrochemistry show the existence of an interconnection between Dacha and Sando Ordovician limestone aquifers. The isotope compositions also show that the groundwater in the Ordovician limestone is a mixture of old groundwater with modern recharge from local infiltration. The maximum percentage of modern water is 71%, which was usually found at the intensively fractured areas. Adopting a model with exponent and piston time distribution, the mean turnover time of groundwater in the Ordovician carbonate rocks was evaluated to be 36 years. The size of the groundwater reservoir is estimated to be 0.134 billion m3 and the mean storage coefficient is 0.0073.
Determination of Transverse Dispersion Coefficients from Reactive Plume Lengths
2005-09-23

Abstract With most existing methods, transverse dispersion coefficients are difficult to determine. We present a new, simple, and robust approach based on steady‐state transport of a reacting agent, introduced over a certain height into the porous medium of interest. The agent reacts with compounds in the ambient water. In our application, we use an alkaline solution injected into acidic ambient water. Threshold values of pH are visualized by adding standard pH indicators. Since aqueous‐phase acid‐base reactions can be considered practically instantaneous and the only process leading to mixing of the reactants is transverse dispersion, the length of the plume is controlled by the ratio of transverse dispersion to advection. We use existing closed‐form expressions for multidimensional steady‐state transport of conservative compounds in order to evaluate the concentration distributions of the reacting compounds. Based on these results, we derive an easy‐to‐use expression for the length of the reactive plume; it is proportional to the injection height squared, times the velocity, and inversely proportional to the transverse dispersion coefficient. Solving this expression for the transverse dispersion coefficient, we can estimate its value from the length of the alkaline plume. We apply the method to two experimental setups of different dimension. The computed transverse dispersion coefficients are rather small. We conclude that at slow but realistic ground water velocities, the contribution of effective molecular diffusion to transverse dispersion cannot be neglected. This results in plume lengths that increase with increasing velocity.
Cone Opsin Mislocalization inRpe65−/−Mice: A Defect That Can Be Corrected by 11-cisRetinal
2005-09-26

The results suggest that the ligand is required during cone opsin synthesis for successful opsin trafficking and that without 11-cis retinal, cones may degenerate because of opsin mislocalization. These results may have important consequences for the treatment of cone dystrophies.
Evaluation of CA125, physical and radiological findings in follow-up of ovarian cancer patients.
2005-09-26

The majority of ovarian cancer patients will suffer from intraabdominal relapse within the first five years after surgery. Today various diagnostic tools, including ultrasound or CT, are available to detect an ovarian cancer recurrence. Radiological examinations at regular time-intervals may lead to the detection of tumor relapse, however these procedures have limited sensitivity and specificity. Moreover, imaging procedures are costly. CA125 is a tumor marker with high sensitivity in ovarian cancer patients. Tumor marker determination is a simple, reproducible technique, and may therefore be useful in routine follow-up in ovarian cancer patients, supplemented with additional imaging procedures. In a retrospective analysis of 58 patients with recurrent ovarian cancer, the sensitivity of clinical examination and tumor marker analysis was compared to radiological findings. Physical interview and physical examination were performed for all patients. CA125 levels were determined in 54 out of 58 patients at the time of diagnosis of recurrence. Forty-seven out of 58 patients received a vaginal ultrasound and 42 were examined by CT scan. In 45 out of 54 (83%) patients, CA 125 was elevated at the time of recurrence. In 45 out of the 58 (78%) patients, a tumor was detected by physical examination. Forty-two out of the 58 patients had CT scans. Pathological findings were seen in 33 out of these patients (80%) Ultrasound revealed tumor recurrence in 33 out of 47 patients (70%). By a follow-up based on physical examination and CA125 determination, 53 out of 54 (98%) patients with recurrences could be identified. In patients with a pelvic recurrence, vaginal examination had the highest sensitivity in comparison to vaginal ultrasound and CT scan. Imaging techniques did not add clinically relevant information during follow-up and should therefore only be performed prior to surgical or therapeutical intervention.
Thick atomic layers of maximum density as bulk terminations of quasicrystals
2005-09-27

The clean surfaces of quasicrystals, orthogonal to the directions of the main\\nsymmetry axes, have a terrace-like appearance. We extend the Bravais' rule for\\ncrystals to quasicrystals, allowing that instead of a single atomic plane a\\nlayer of atomic planes may form a bulk termination.\\n
Functional redundancy of PIN proteins is accompanied by auxin-dependent cross-regulation of PIN expression
2005-09-28

Plant development displays an exceptional plasticity and adaptability that involves the dynamic, asymmetric distribution of the phytohormone auxin. Polar auxin flow, which requires polarly localized transport facilitators of the PIN family, largely contributes to the establishment and maintenance of the auxin gradients. Functionally overlapping action of PIN proteins mediates multiple developmental processes, including embryo formation, organ development and tropisms. Here we show that PIN proteins exhibit synergistic interactions,which involve cross-regulation of PIN gene expression in pin mutants or plants with inhibited auxin transport. Auxin itself positively feeds back on PIN gene expression in a tissue-specific manner through an AUX/IAA-dependent signalling pathway. This regulatory switch is indicative of a mechanism by which the loss of a specific PIN protein is compensated for by auxin-dependent ectopic expression of its homologues. The compensatory properties of the PIN-dependent transport network might enable the stabilization of auxin gradients and potentially contribute to the robustness of plant adaptive development.
Benign Partial Epilepsy in Childhood: Selective Cognitive Deficits Are Related to the Location of Focal Spikes Determined by Combined EEG/MEG
2005-09-28

Summary: Purpose: Benign partial epilepsy (BPE) in childhood is characterized by the occurrence of interictal stereotyped focal spikes with variable localization in the EEG. Children with BPE often exhibit neuropsychological deficits. It is unclear whether a correlation exists between these deficits and the localization of spikes, several EEG studies giving inconsistent results. Magnetoencephalography (MEG) improves the accuracy of spike localization. Therefore by using combined MEG/EEG, we investigated the topographic relation between focal spikes and neuropsychological findings in children with BPE. Methods: Twenty‐seven children diagnosed consecutively with BPE were enrolled in the study. All were examined by combined MEG/EEG and magnetic resonance imaging (MRI). Location of spikes was determined by dipole source estimation. A standardized neuropsychological assessment was conducted, including Kaufman ABC battery, language tests, and motor performance series. All children with sufficient MEG data were included in the correlation analysis (N = 20). Results: Focal spikes were located in the perisylvian region in 13 children, in the occipital region in seven, and in the frontal region in one. Five children had bilateral or multiple foci. Children with left perisylvian spikes did not differ from the others in global IQ, but performed significantly lower in language tests (p = 0.01). Children with occipital spikes performed significantly lower in simultaneous information processing (p = 0.01), especially in visual transformation tasks. Conclusions: Combined MEG/EEG investigation is a useful tool to examine interictal focal spikes. Our results show a correlation between the location of spikes and selective cognitive deficits in children with BPE. These findings indicate that focal interictal spikes may interfere with complex cognitive functions.
New mutations in protein kinase Cγ associated with spinocerebellar ataxia type 14
2005-09-28

Abstract Autosomal dominant cerebellar ataxias (ADCA) are a heterogeneous group of neurological disorders. Point mutations in the gene encoding protein kinase Cγ ( PRKCG ) are responsible for spinocerebellar ataxia 14 (SCA14). We screened for mutations in the PRKCG gene, in a large series of 284 ADCA index cases, mostly French (n=204) and German (n=48), in whom CAG repeat expansions in the known SCA genes were previously excluded. Six mutations were found that segregated with the disease and were not detected on 560 control chromosomes, including F643L (exon 18), already reported in another French kindred. Five new missense mutations were identified in exons 4 (C114Y/G123R/G123E), 10 (G360S) and 18 (V692G). All but one (V692G) were located in highly conserved regions of the regulatory or catalytic domains of the protein. All six SCA14 families were French and there was no evidence of reduced penetrance. The phenotype consisted in a very slowly progressive cerebellar ataxia with a mean age at onset of 33.5±14.2 years (range 15 to 60 years), occasionally associated with executive dysfunction, myoclonus, myorythmia, tremor or decreased vibration sense. SCA14 represented only 1.5% (7/454) of French ADCA families but none of the German families. It should, however, be considered in patients with slowly progressive ADCA, particularly when myoclonus and cognitive impairment are present. Ann Neurol 2005
Synthetic Colloids Attenuate Leukocyte-Endothelial Interactions by Inhibition of Integrin Function
2005-09-28

Background It has been suspected that synthetic colloids may interfere with leukocyte adhesion by down-regulation of endothelial cell adhesion molecules. Although inhibition of endothelial inflammation might reduce leukocyte-related tissue injury, the same mechanism may be detrimental for host defense during severe infection. Regarding the widespread use of colloids, the authors performed a laboratory investigation to determine the mechanisms by which synthetic colloids interfere with leukocyte-endothelial interactions. Methods Adhesion molecule expression on native and cytokine-activated endothelium from umbilical veins was measured after pretreatment with gelatin and various preparations of dextran or hydroxyethyl starch. Inhibition of neutrophil adhesion to activated endothelium was examined in a flow chamber by perfusion of untreated and colloid-treated neutrophils over colloid-pretreated endothelium at 2 dyn/cm. Comparisons were made between untreated controls, colloid-pretreated endothelium, and colloid-cotreated neutrophils. Results Intercellular adhesion molecule 1, vascular cell adhesion molecule 1, E-selectin, and P-selectin were not attenuated by any colloid. Accordingly, colloid pretreatment of endothelium alone did not reduce neutrophil adhesion. In contrast, when neutrophils were cotreated by addition of colloids to the perfusate immediately before perfusion, adhesion decreased by 31-51% (P &lt; 0.05) regardless of the colloid type. As indicated by the twofold increased rolling fractions, this reduction was due to an inhibition of neutrophil integrins. Conclusions This study shows that synthetic colloids inhibit neutrophil adhesion by a neutrophil-dependent mechanism rather than interfering with endothelial cell activation. This suggests that inhibition of leukocyte sequestration by volume support is a common and transient phenomenon depending on the colloid concentration in plasma.
The “Anesthetic Cascade”: Fact or Fiction?
2005-09-28

To the Editor:-We read with interest the study by Scavone et al. 1 that demonstrates the absence of efficacy of a prophylactic epidural blood patch after inadvertent dural puncture.We suggest that two factors could have influenced the negative result of this trial.First, inadvertent dural puncture could have been overdiagnosed, namely when loss of resistance to saline was used to locate epidural space.This could explain the lower incidence of post-dural puncture headache and less frequent realization of therapeutic epidural blood patch reported in this study compared with others. 2,3 Second, 20 ml may not be the adequate blood volume to test a prophylactic epidural blood patch.This volume has tended to increase over time to 20 ml or more, 23 Ϯ 5 ml in a study by Safat-Tisseront et al. 3 The optimal blood volume may be the volume at which pain in the back, buttocks, or legs occurs, which was only achieved for seven patients in the study of Scavone et al.This higher volume may lead to either a larger patch over the dural tear or a significantly higher increase in lumbar and intracranial pressure, leading to reduced cerebral vasodilation.
A Randomized Controlled Trial Assessing Infectious Disease Risks from Bathing in Fresh Recreational Waters in Relation to the Concentration of Escherichia coli , Intestinal Enterococci, Clostridium perfringens , and Somatic Coliphages
2005-09-29

We performed epidemiologic studies at public freshwater bathing sites in Germany to provide a better scientific basis for the definition of recreational water quality standards. A total of 2,196 participants were recruited from the local population and randomized into bathers and nonbathers. Bathers were exposed for 10 min and had to immerse their head at least three times. Water samples for microbiological analysis were collected at 20-min intervals. Unbiased concentration-response effects with no-observed-adverse-effect levels (NOAELs) were demonstrated for three different definitions of gastroenteritis and four fecal indicator organisms. Relative risks for bathing in waters with levels above NOAELs compared with nonbathing ranged from 1.8 (95% CI, 1.2-2.6) to 4.6 (95% CI, 2.1-10.1), depending on the definition of gastroenteritis. The effect of swallowing water provided additional evidence for true dose-response relationships. Based on the NOAELs, the following guide values for water quality are suggested: 100 Escherichia coli, 25 intestinal enterococci, 10 somatic coliphages, or 10 Clostridium perfringens per 100 mL. Recreational water quality standards are intended to protect the health of those consumers who are not already immune or resistant to pathogens that may be associated with indicator organisms. In contrast to current World Health Organization recommendations, we concluded that standards should be based on rates of compliance with NOAELs rather than on attributable risks determined above NOAELs, because these risks depend mainly on the unpredictable susceptibility of the cohorts. Although in theory there is no threshold in real concentration-response relationships, we demonstrated that a NOAEL approach would be a more robust and practical solution to the complex problem of setting standards.
Acute Effect of Rheopheresis on Peripheral Endothelial Dysfunction in Patients Suffering From Sudden Hearing Loss
2005-09-30

Abstract: Single low density lipoprotein (LDL) fibrinogen apheresis has shown beneficial effects in the treatment of patients with sudden sensorineural hearing loss (SSHL). Pathophysiologically, a microcirculatory disorder of the inner ear, probably caused by disturbed endothelial function, is discussed as a final common pathway of a variety of SSHL etiologies. Thus, we carried out a prospective pilot study on the efficacy of Rheopheresis on vascular function in these patients, embedded into an ongoing randomized controlled multicenter trial investigating the efficacy of Rheopheresis for the treatment of SSHL. Potential modulation of systemic endothelial dysfunction by Rheopheresis was examined by measuring flow‐associated vasodilatation of the brachial artery (according to the criteria of the American College of Cardiology) in a small group of patients suffering from SSHL ( N = 6, 5m/1f, mean age 56 ± 11 years) within the last 3 days. At baseline, five of the six patients with acute hearing loss showed endothelial dysfunction as evidenced by diminished flow‐mediated vasodilatation (FMD &lt; 5%). After a single Rheopheresis treatment, flow‐mediated vasodilatation improved significantly (from 3.9 ± 3.6% to 7.2 ± 2.4%, P = 0.05, mean ± SD, two‐sided paired T ‐test). This was paralleled by a reduction in fibrinogen (364 ± 216 mg/dL to 142 ± 96 mg/dL, P = 0.03), total cholesterol (228 ± 23 to 98 ± 10, P &lt; 0.0001) and LDL cholesterol levels (153 ± 8 mg/dL to 83 ± 23 mg/dL, P &lt; 0.01). Based on this case series we conclude that single Rheopheresis treatment might have an acute beneficial effect on endothelial dysfunction in patients suffering from SSHL.
Compositional Evolution of the Emplaced Fuel Source in the Vadose Zone Field Experiment at Airbase Værløse, Denmark
2005-09-30

A field experiment was performed in a sandy vadose zone, studying the fate of an emplaced fuel-NAPL source, composed of 13 hydrocarbons and a tracer. The UNIFAC model was used to testthe nonideal behavior of the source, and the numerical model MIN3P was used for assessing the effect of biodegradation on source evolution. The diffusive loss to the surrounding vadose zone and the atmosphere created temporary gradients in mole fractions of the individual compounds within the source NAPL. The evolution of the source composition corresponded in general with expectations based on Raoult's Law, with the exception thatthe mole fractions of aromatic compounds in the source NAPL decreased faster than fractions of aliphatic compounds of similar volatility. Calculation of activity coefficients (y) using the UNIFAC model implied nonideal conditions, with composition-dependent gammas different from 1. Positive deviations were calculated for the aromatic compounds. The effect of biodegradation on source depletion, evaluated by numerical modeling, was greater for the aromatic as compared to the aliphatic compounds. Hence, the faster depletion of the aromatic relative to aliphatic compounds of similar volatility is both a result of the nonideality of the mixture and a result of partitioning and biodegradation in the pore-water. Vapor concentrations of the compounds in the source were in reasonable agreement with predictions based on the modified Raoult's Law with the UNIFAC predicted gammas and the NAPL composition for the most volatile compounds. For the less volatile compounds, the measured vapor concentrations were lower than predicted with the largest deviations for the least volatile compounds. This field experiment illustrated that nonideal behavior and bioenhanced source depletion need to be considered at multicomponent NAPL spill sites.
Communal use of integumental wounds in honey bee (Apis mellifera) pupae multiply infested by the ectoparasitic mite Varroa destructor.
2005-09-30

The ectoparasitic bee mite, Varroa destructor, is highly adapted to its natural and adopted honey bee hosts, Apis cerana and Apis mellifera. Adult females perforate the integument of bee pupae in such a way that they and their progeny can feed. We examined the wounds that founder females made, and usually found one, and rarely up to three, integumental wounds on pupae of A. mellifera multiply infested by V. destructor. The punctures were mainly on the 2nd abdominal sternite of the host. These perforations are used repeatedly as feeding sites by these hemolymph-sucking mites and by their progeny. The diameter of the wounds increased during pupal development. In brood cells containing 4-5 invading female mites and their progeny, healing of the wound is delayed, normally occurring just before the imaginal moult of the bee pupa. These wounds are subject to microbial infections, and they are relevant to the evolution of behavioral traits in these parasitic mites and their relations to host bees.
T cell epitope definition by differential mass spectrometry: Identification of a novel, immunogenic HLA‐B8 ligand directly from renal cancer tissue
2005-09-30

Abstract In this study, we describe a differential mass spectrometric technique for the immuno‐proteomic analysis of the major histocompatibility complex (MHC) peptides of a renal cell carcinoma (RCC) biopsy compared with the healthy kidney tissue of the same patient after nephrectomy. Using a stable isotope labeling approach, we could directly compare and relatively quantify 43 MHC‐peptide pairs, most of which were present in similar proportions on both normal kidney and tumor. Significantly, two dominant peptides of monoisotopic masses ([M+H] + ) 973.43 u and 967.59 u, respectively, were found exclusively in the tumor sample. One of these was identified as originating from heme oxygenase‐1 (HO‐1), a protein involved in induction of apoptosis resistance, immuno‐suppression and neoangiogenesis and reported to be up‐regulated in various cancer types. Moreover, the corresponding synthetic HO‐1‐derived peptide was shown to be immunogenic in vitro by generation of CD8 + T cell lines with peptide‐specific cytolytic activity. Thus, this peptide is an example of a differentially identified T cell epitope that could be considered as a target for immunotherapy.