julilili42/papers huggingface dataset:
The multiwavelength variability of 3C 273
2008-05-22

Aims. We present an update of the 3C 273's database hosted by the ISDC, completed with data from radio to gamma-ray observations over the last 10 years. We use this large data set to study the multiwavelength properties of this quasar, especially focussing on its variability behaviour.&lt;br/&gt;Methods. We study the amplitude of the variations and the maximum variability time scales across the broad-band spectrum and correlate the light curves in different bands, specifically with the X-rays, to search for possible connections between the emission at different energies.&lt;br/&gt;Results. 3C 273 shows variability at all frequencies, with amplitudes and time scales strongly depending on the energy and being the signatures of the different emission mechanisms. The variability properties of the X-ray band imply the presence of either two separate components (possibly a Seyfert-like and a blazar-like) or at least two parameters with distinct timing properties to account for the X-ray emission below and above ~20 keV. The dominant hard X-ray emission is most probably not due to electrons accelerated by the shock waves in the jet as their variability does not correlate with the flaring millimeter emission, but seems to be associated to long-timescale variations in the optical. This optical component is consistent with being optically thin synchrotron radiation from the base of the jet and the hard X-rays would be produced through inverse Compton processes (SSC and/or EC) by the same electron population. We show evidence that this synchrotron component extends from the optical to the near-infrared domain, where it is blended by emission of heated dust that we find to be located within about 1 light-year from the ultraviolet source.
The multiwavelength variability of 3C 273
2008-05-22

Aims. We present an update of the 3C 273's database hosted by the ISDC, completed with data from radio to gamma-ray observations over the last 10 years. We use this large data set to study the multiwavelength properties of this quasar, especially focussing on its variability behaviour. Methods. We study the amplitude of the variations and the maximum variability time scales across the broad-band spectrum and correlate the light curves in different bands, specifically with the X-rays, to search for possible connections between the emission at different energies. Results. 3C 273 shows variability at all frequencies, with amplitudes and time scales strongly depending on the energy and being the signatures of the different emission mechanisms. The variability properties of the X-ray band imply the presence of either two separate components (possibly a Seyfert-like and a blazar-like) or at least two parameters with distinct timing properties to account for the X-ray emission below and above ~20 keV. The dominant hard X-ray emission is most probably not due to electrons accelerated by the shock waves in the jet as their variability does not correlate with the flaring millimeter emission, but seems to be associated to long-timescale variations in the optical. This optical component is consistent with being optically thin synchrotron radiation from the base of the jet and the hard X-rays would be produced through inverse Compton processes (SSC and/or EC) by the same electron population. We show evidence that this synchrotron component extends from the optical to the near-infrared domain, where it is blended by emission of heated dust that we find to be located within about 1 light-year from the ultraviolet source.
Age‐dependent normative values for differential luminance sensitivity in automated static perimetry using the Octopus 101
2008-05-22

Abstract. Purpose: To determine age‐dependent normative differential threshold values for the Octopus 101 instrument and to create a smooth mathematical model characterizing the age‐dependency and asymmetry of the hill of vision. Methods: Static automated perimetry within the central 30° visual field (VF) was conducted with the Octopus 101 (background luminance 10 cd/m 2 ) in 81 eyes of 81 ophthalmologically healthy subjects (11–12 per decade of age) aged 10–79 years. A 4‐2‐2 staircase strategy with three reversals was run. The test point grid consisted of 68 concentrically arranged points with test point condensation towards the VF centre, representing the approximately rotation‐symmetrical 30° hill of vision. Thresholds of differential luminance sensitivity (DLS) were estimated by the maximum likelihood method. A smooth mathematical model was fitted to the normative data. Results: The model fit was satisfactory ( r 2 = 0.74). Covariables were: age, eccentricity, angle and subject. Total random standard deviation (SD) was 1.75 dB. The residual SD exceeded 1.75 dB in the border region, was 1.5 dB within the centre and fell below 1.25 dB in a ring around the centre. Average thresholds of DLS varied with age quadratically. It is close to constant for the 10–40–year‐old age group and declines ever more steeply thereafter. The effect of age on DLS in the VF increased with eccentricity. The greatest drop was located in the peripheral superior hemifield: at 25° eccentricity the superior DLS was estimated to be 5.5 dB higher in 10‐year‐olds than in 75‐year‐olds. Conclusions: This new smooth model allows for the prediction of age‐related normal threshold values for any stimulus location within the 30° VF and thus for the calculation of global and local measures of defect such as mean defects or p‐values for any type of stimulus.
Anamorphs in the Strophariaceae (Basidiomycota, Agaricales)
2008-05-22

We describe and illustrate conidiogenesis in 21 species of Strophariaceae sensu Singer in culture, including first reports of conidiogenesis from nine species. Two modes of thallic conidiogenesis were revealed. The first mode, present in Hypholoma capnoides (Fr.) P. Kumm., Hypholoma fasciculare (Fr.) P. Kumm., Hypholoma marginatum (Pers.) J. Schröt., Hypholoma subericaeum (Fr.) Kühner, Hypholoma sublateritium (Schaeff.) Quél., Kuehneromyces mutabilis (Schaeff.) Singer &amp; A.H. Sm., Pholiota lenta (Pers.) Singer, Pholiota lucifera (Lasch) Quél., Pholiota mixta (Fr.) Kuyper &amp; Tjall.-Beuk., Pholiota spumosa (Fr.) Singer, Psilocybe cf. coprophila (Bull.) P. Kumm., Psilocybe inquilina (Fr.) Bres., Psilocybe semilanceata (Fr.) P. Kumm., Psilocybe sp., Stropharia rugosoannulata Farl. ex Murrill, and Stropharia semiglobata (Batsch) Quél., is characterized by straight or often coiled conidiogenous hyphae, not or only slightly sympodially proliferating conidiophores lacking geniculate parts, and hyaline, rod-shaped conidia. Conidiogenesis in Pholiota aurivella (Batsch) P. Kumm., Pholiota gummosa (Lasch) Singer, and Pholiota squarrosa (Batsch) P. Kumm. followed a second mode, distinguished by straight conidiogenous hyphae, sympodially proliferating geniculate conidiophores, and coloured, swollen conidia formed on older mycelia. These two modes also differed concerning the number of nuclei in the conidia. Pholiota alnicola (Fr.) Singer and Pholiota tuberculosa (Schaeff.) P. Kumm. possessed specific modes of conidiogenesis that deviated from the two prevalent modes described above. Careful analysis of anamorph descriptions compiled from literature supports these modes and allows conidia to be distinguished from nondetaching hyphal swellings that have also been designated as conidia in the past.
Tradition, History, and Our Story: Some Observations on Jacob and Esau in the Books of Obadiah and Malachi
2008-05-22

In both Genesis and early prophecy, Jacob, the father of the chosen people of Israel, is harshly criticized for the shrewd trickery that he employs to supplant his brother Esau. The role reversal of the twins thus challenges later biblical authors. It is argued in this study that, from the way this tradition is used for purposes of communication in Obadiah and Malachi, two alternative interpretations may be discerned. While Obadiah explains the role reversal as a result of Esau's misconduct, Malachi interprets it as an inscrutable act of divine election. Tracing the latter approach in Paul's letter to the Romans, both the bearing of these actualizing interpretations on the tradition itself and the way different communities used it as common story are observed.
Sex differences in a transgenic rat model of Huntington's disease: decreased 17β-estradiol levels correlate with reduced numbers of DARPP32+ neurons in males
2008-05-23

Recent clinical studies have highlighted that female sex hormones represent potential neuroprotective mediators against damage caused by acute and chronic brain diseases. This evidence has been confirmed by experimental studies documenting the protective role of female sex hormones both in vitro and in vivo, although these studies did not specifically focus on Huntington's disease (HD). We therefore investigated the onset and course of HD in female and male transgenic (tg) HD (CAG(n51)) and control rats across age and focused on three aspects: (i) behavioral and physiological alterations (energy expenditure, home-cage activity, emotional disturbance and motor dysfunction), (ii) morphological markers (numbers and characteristics of striatal DARPP32(+) medium-sized spiny neurons (MSNs) and dopamine receptor autoradiography) and (iii) peripheral sex hormone levels as well as striatal estrogen receptor expression. Independent of their sex, tgHD rats exhibited increased levels of food intake, elevated home-cage activity scores and anxiolytic-like behavior, whereas only males showed an impairment of motor function. In line with the latter finding, loss and atrophy of DARPP32(+) MSNs were apparent only in male tgHD rats. This result was associated with a decreased striatal dopamine D1 receptor density and lower plasma levels of 17beta-estradiol at the age of 14 months. As DARPP32(+) MSNs expressed both alpha- and beta-estrogen receptors and showed a correlation between cell numbers and 17beta-estradiol levels, our findings suggest sex-related differences in the HD phenotype pointing to a substantial neuroprotective effect of sex hormones and opening new perspectives on the therapy of HD.
Exact relativistic tritium β-decay endpoint spectrum in a hadron model
2008-05-23

We present the relativistic calculation of the beta-decay of tritium in a hadron model. The elementary particle treatment of the transition 3H -> 3He + e^- + nu_e is performed in analogy with the description of the beta-decay of neutron. The effects of higher order terms of hadron current and nuclear recoil are taken into account in this formalism. The relativistic Kurie function is derived and presented in a simple form suitable for the determination of neutrino masses from the shape of the endpoint spectrum. A connection with the commonly used Kurie function is established.
Homoleptic Cadmium and Mercury Compounds of Stanna-closo-dodecaborate
2008-05-23

The reaction of stanna- closo-dodecaborate [SnB 11H 11] (2-) (1) with CdBr 2 gave the tetrahedrally coordinated compound [Cd(SnB 11H 11) 4] (6-)(2). The same coordination mode can be found in [Hg(SnB 11H 11) 4] (6-) (3), which was obtained by reaction of stannaborate with Hg 2Cl2. Both compounds were characterized by single crystal X-ray analysis and heteronuclear NMR techniques.
Antipyretic effect of ibuprofen in Gabonese children with uncomplicated falciparum malaria: a randomized, double-blind, placebo-controlled trial
2008-05-26

Abstract Background Antipyretic drugs are widely used in children with fever, though there is a controversy about the benefit of reducing fever in children with malaria. In order to assess the effect of ibuprofen on fever compared to placebo in children with uncomplicated Plasmodium falciparum malaria in Gabon, a randomized double blind placebo controlled trial, was designed. Methods Fifty children between two and seven years of age with uncomplicated malaria were included in the study. For the treatment of fever, all patients "received" mechanical treatment when the temperature rose above 37.5°C. In addition to the mechanical treatment, continuous fanning and cooling blanket, patients were assigned randomly to receive ibuprofen (7 mg/kg body weight, every eight hours) or placebo. Results The fever clearance time using a fever threshold of 37.5°C was similar in children receiving ibuprofen compared to those receiving placebo. The difference was also not statistically significant using a fever threshold of 37.8°C or 38.0°C. However, the fever time and the area under the fever curve were significantly smaller in the ibuprofen group compared to the placebo group. Conclusion Ibuprofen is effective in reducing the time with fever. The effect on fever clearance is less obvious and depends on definition of the fever threshold. Trial registration The trial registration number is: NCT00167713
Building the “Phosphoindigo” Backbone by Oxidative Coupling of Phosphindolin‐3‐ones with Selenium Dioxide
2008-05-26

Abstract Oxidative coupling of racemic 1‐ethoxy‐1‐oxophosphindolin‐3‐one ( 1 ) and its 5‐CF 3 ‐derivative 6 with SeO 2 furnishes 1,1′‐diphosphaindigo derivatives 5 and 7 as bis‐phosphinic esters, i. e. as P V ‐compounds. Like indigo and thioindigo, 5 and 7 exist in the E ‐configuration; the crude products of 5 and 7 are mixtures of isomers that are trans ‐ and cis ‐configurated with respect to the relative orientation of the ester groups oat phosphorus. The structure of the centrosymmetric E ‐P( R )P′( S ) isomer [ (E)‐trans ‐isomer] of 5 was determined by X‐ray crystallography. Ester cleavage of 5 , followed by addition of triethylamine to bis‐phosphinic acid 9 (the 1,1,1′,1′‐tetroxide of “ phosphoindigo ”), furnishes the related bis‐triethylammonium salt 10 as a crystalline hydrate that exhibits an extended hydrogen bonding network.
Das 1,3‐Dimethylcyanurat‐Ion als ambidenter Ligand
2008-05-26

Abstract The 1,3‐Dimethylcyanurate Ion as an Ambident Ligand 1,3‐Dimethyl‐2,4,6‐trioxo‐1,3,5‐triazin ( 7 ), (1,3‐dimethylcyanuric acid, DMCH), obtained from the thermolysis of methyl urea, is deprotonated with lithium ethylate. In the resulting dinuclear complex [(DMCLi) 2 ·4 H 2 O] ( 8 ), the heterocyclic anions are linked to the lithium centres with oxygen atoms as its enolate form. In the corresponding silver complex [(DMCAg) 2 ·en] ( 10 ), (en = ethylendiamine), N ‐coordination of the ligand is observed. The crystal structures of 7 , 8 , and 10 reveal the presence of intermolecular hydrogen bonds.
Synthese und Kristallstruktur der Rhenium(VII)‐Nitridchloride ReNCl4 und ReNCl4·H2O
2008-05-26

Abstract Syntheses and Crystal Structures of the Rhenium(VII) Nitride Chlorides ReNCl 4 and ReNCl 4 ·H 2 O Rhenium(VII) nitride chloride, ReNCl 4 ( 1 ) is obtained in form of brown needles with metallic luster by the reaction of ReCl 5 with Cl 3 VNCl at 140 °C under vacuum in a sealed glass ampoule. It crystallizes in the tetragonal space group I4 with the lattice parameters a = 826.7(4), c = 405.1(2) pm, and Z = 2. The square pyramidal molecules are connected by asymmetric nitrido bridges to form chains along the crystallographic c axis. The shorter Re‐N distance of 163.0(5) pm corresponds to a triple bond, while the pronounced longer distance of 242.0(5) pm can be interpreted with a weak donor bond. The reaction of ReCl 5 with VN at 170 °C under vacuum in a sealed glass ampoule yields red needles of ReNCl 4 ·H 2 O ( 2 ). It crystallizes in the orthorhombic space group Pnma with a = 1075.4(2), b = 1108.5(2), c = 547.7(5) pm and Z = 4. The Re atoms exhibit a distorted octahedral coordination with the aqua ligand in trans position to the nitrido ligand. The Re‐N triple bond has a bond distance of 166.1(11) pm. The complexes are connected by hydrogen bridges O‐H···N to form chains.
DIALIGN-TX: greedy and progressive approaches for segment-based multiple sequence alignment
2008-05-27

On BALIBASE3, our new program performs significantly better than the previous program DIALIGN-T and outperforms the popular global aligner CLUSTAL W, though it is still outperformed by programs that focus on global alignment like MAFFT, MUSCLE and T-COFFEE. On the locally related test sets in IRMBASE 2 and DIRM-BASE 1, our method outperforms all other programs while MAFFT E-INSi is the only method that comes close to the performance of DIALIGN-TX.
Segmental Pulmonary Vein Ablation: Success Rates with and without Exclusion of Areas Adjacent to the Esophagus
2008-05-27

Background: Catheter ablation has become the first line of therapy in patients with symptomatic recurrent, drug‐refractory atrial fibrillation (AF). The occurrence of an atrioesophageal fistula is a rare but serious complication after AF‐ablation procedures. This risk is even present during segmental pulmonary vein (PV) ablation procedures because the esophagus does frequently have a very close anatomical relationship to the right or left PV ostia. The aim of the present study was to analyze whether the exclusion of areas adjacent to the esophagus does have a significant effect on the success rates after segmental pulmonary vein ablation procedures. Methods: Forty‐three consecutive patients with symptomatic paroxysmal AF were enrolled in this study. In all patients, a segmental PV ablation procedure was performed. The procedures were facilitated by a 3D real‐time visualization of the circumferential mapping catheter placed in the pulmonary veins using the NavXTM system (St. Jude Medical, St. Paul, MN, USA; open irrigated tip ablation catheter; 43°C; 30 W). In 21 patients, a complete ostial PV isolation was attempted regardless of the anatomical relationship between the ablation sites and the esophagus (group A). In the remaining 22 patients, the esophagus was marked by a stomach tube and areas adjacent to the esophagus were excluded from the ablation procedure (group B). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, and 6 months after the ablation procedure . Results: The segmental pulmonary vein ablation procedure could be performed as planned in all patients. In group A, all pulmonary veins could be isolated successfully in 14 out of 21 patients (67%). A mean number of 3.7 pulmonary veins (SD ± 0.5 PVs) were isolated per patient. The main reasons for an incomplete PV isolation were: small diameter of the PVs, side branches close to the ostium, or poorly accessible PV ostia. In group B, all PVs could be isolated successfully in only 12 out of 22 patients (55%; P = 0.54). A mean number of 3.2 PVs (SD ± 0.9 PVs) were isolated per patient (P = 0.05). This was mostly due to a close anatomical relationship to the esophagus. The ablation strategy had to be modified in 16/22 patients in group B because of a close anatomical relationship between the left (n = 10) or right (n = 6) PV ostia and the esophagus. After 3 months, the percentage of patients free from an AF recurrence was not significantly different between the two groups (90% vs 95%; P = 0.61). After 6 months, there was no significant difference between the success rates either (81% vs 82%; P = 1.0). There were no major complications in both groups. Conclusions: The exclusion of areas adjacent to the esophagus results in a moderately higher percentage of incompletely isolated PVs. However, it does not have a significant effect on the AF recurrence rate during short‐term and mid‐term follow‐up.
Aortic calcification on plain chest radiography predicts embolic complications during carotid artery stenting
2008-05-27

Background and purpose: Aortic arch calcification (AC) on conventional angiograms has recently been shown to be associated with embolic complications during carotid artery stenting (CAS). Because conventional angiography is not routinely carried out in patients prior to CAS, a less invasive, commonly available diagnostic modality is warranted to identify AC. Methods: We investigated the occurrence of AC on routinely acquired chest radiographs and its influence on diffusion‐weighted imaging (DWI) lesions as surrogate markers for stroke. Results: A total of 152 patients (mean age: 67.5 ± 8.9 years, 112 men) underwent CAS and completed pre‐ and post‐procedural DWI. AC larger than 1 cm in length was classified as relevant and could be detected in 63 patients (41.4%) on plain chest radiographs. In patients with AC, significantly more new DWI‐lesions were found than in patients without AC [median 2; interquartile range (IQR): 0–7 vs. median 1, IQR: 0–2; P &lt; 0.05]. After multivariate regression analysis, AC was independently associated with new post‐procedural DWI lesions. Discussion: AC is a common finding in patients with a high‐grade carotid stenosis and predicts embolic complications during CAS. Since AC can be detected on plain chest radiography, this diagnostic tool is useful to identify high‐risk patients for CAS.
Non-invasive 3D-Visualization with Sub-micron Resolution Using Synchrotron-X-ray-tomography
2008-05-27

Little is known about the internal organization of many micro-arthropods with body sizes below 1 mm. The reasons for that are the small size and the hard cuticle which makes it difficult to use protocols of classical histology. In addition, histological sectioning destroys the sample and can therefore not be used for unique material. Hence, a non-destructive method is desirable which allows to view inside small samples without the need of sectioning. We used synchrotron X-ray tomography at the European Synchrotron Radiation Facility (ESRF) in Grenoble (France) to non-invasively produce 3D tomographic datasets with a pixel-resolution of 0.7microm. Using volume rendering software, this allows us to reconstruct the internal organization in its natural state without the artefacts produced by histological sectioning. These date can be used for quantitative morphology, landmarks, or for the visualization of animated movies to understand the structure of hidden body parts and to follow complete organ systems or tissues through the samples.
Non-invasive 3D-Visualization with Sub-micron Resolution Using Synchrotron-X-ray-tomography
2008-05-27

Little is known about the internal organization of many micro-arthropods with body sizes below 1 mm. The reasons for that are the small size and the hard cuticle which makes it difficult to use protocols of classical histology. In addition, histological sectioning destroys the sample and can therefore not be used for unique material. Hence, a non-destructive method is desirable which allows to view inside small samples without the need of sectioning. We used synchrotron X-ray tomography at the European Synchrotron Radiation Facility (ESRF) in Grenoble (France) to non-invasively produce 3D tomographic datasets with a pixel-resolution of 0.7μm. Using volume rendering software, this allows us to reconstruct the internal organization in its natural state without the artefacts produced by histological sectioning. These date can be used for quantitative morphology, landmarks, or for the visualization of animated movies to understand the structure of hidden body parts and to follow complete organ systems or tissues through the samples.