julilili42/papers huggingface dataset:
New challenges for tafoni research. A new approach to understand processes and weathering rates
2010-12-09

Abstract Cavernous tafoni‐type weathering is a common and conspicuous global feature, creating artistic sculptures, which may be relevant for geochemical budgets. Weathering processes and rates are still a matter of discussion. Field evidence in the type locality Corsica revealed no trend of size variability from the coast to subalpine elevations and the aspect of tafoni seems to be governed primarily by the directions of local fault systems and cleavage, and only subordinately by wind directions or the aspect of insulation. REM analysis of fresh tafone chips confirmed mechanical weathering by the crystallization of salts, as conchoidal fracturing of quartz is observed. The salts are only subordinately provided by sea spray, as calcium and sodium sulfates rather than halite dominate even close to the coast. Characteristic element ratios compare well with aerosols from mixed African and European air masses. Sulfates are largely derived from Sahara dust, indicated by their sulfur isotopic composition. Salt crystals form by capillary rise within the rock and subsequent crystallization in micro‐cracks and at grain boundaries inside rain‐protected overhangs. Siderophile bacteria identified by raster electron microscopy (REM) analysis of tafone debris contribute to accelerated weathering of biotite and tiny sulfide ore minerals. By applying 10 Be‐exposure dating, weathering rates of large mature tafone structures were found to be about an order of magnitude higher than those on the exposed top of the affected granite blocks. Copyright © 2010 John Wiley &amp; Sons, Ltd.
Finding a 24-day orbital period for the X-ray binary 1A 1118-616
2010-12-09

We report the first determination of the binary period and orbital ephemeris of the Be X-ray binary containing the pulsar 1A 1118-616 (35 years after the discovery of the source). The orbital period is found to be Porb = 24.0 ± 0.4days. The source was observed by RXTE during its last large X-ray outburst in January 2009, which peaked at MJD 54845.4, by taking short observations every few days, covering an elapsed time comparable to the orbital period. Using the phase connection technique, pulse arrival time delays could be measured and an orbital solution determined. The data are consistent with a circular orbit and the time of 90 degrees longitude was found to be Tπ/2 = MJD 54845.37(10), which is coincident with that of the peak X-ray flux.
A key role for cyclic nucleotide gated (CNG) channels in cGMP-related retinitis pigmentosa
2010-12-10

The rd1 natural mutant is one of the first and probably the most commonly studied mouse model for retinitis pigmentosa (RP), a severe and frequently blinding human retinal degeneration. In several decades of research, the link between the increase in photoreceptor cGMP levels and the extremely rapid cell death gave rise to a number of hypotheses. Here, we provide clear evidence that the presence of cyclic nucleotide gated (CNG) channels in the outer segment membrane is the key to rod photoreceptor loss. In Cngb1(-/-) × rd1 double mutants devoid of regular CNG channels, cGMP levels are still pathologically high, but rod photoreceptor viability and outer segment morphology are greatly improved. Importantly, cone photoreceptors, the basis for high-resolution daylight and colour vision, survived and remained functional for extended periods of time. These findings strongly support the hypothesis of deleterious calcium (Ca(2+))-influx as the cause of rapid rod cell death and highlight the importance of CNG channels in this process. Furthermore, our findings suggest that targeting rod CNG channels, rather than general Ca(2+)-channel blockade, is a most promising symptomatic approach to treat otherwise incurable forms of cGMP-related RP.
Vax2 regulates retinoic acid distribution and cone opsin expression in the vertebrate eye
2010-12-10

Vax2 is an eye-specific homeobox gene, the inactivation of which in mouse leads to alterations in the establishment of a proper dorsoventral eye axis during embryonic development. To dissect the molecular pathways in which Vax2 is involved, we performed a transcriptome analysis of Vax2–/– mice throughout the main stages of eye development. We found that some of the enzymes involved in retinoic acid (RA) metabolism in the eye show significant variations of their expression levels in mutant mice. In particular, we detected an expansion of the expression domains of the RA-catabolizing enzymes Cyp26a1 and Cyp26c1, and a downregulation of the RA-synthesizing enzyme Raldh3. These changes determine a significant expansion of the RA-free zone towards the ventral part of the eye. At postnatal stages of eye development, Vax2 inactivation led to alterations of the regional expression of the cone photoreceptor genes Opn1sw (S-Opsin) and Opn1mw (M-Opsin), which were significantly rescued after RA administration. We confirmed the above described alterations of gene expression in the Oryzias latipes (medaka fish) model system using both Vax2 gain- and loss-of-function assays. Finally, a detailed morphological and functional analysis of the adult retina in mutant mice revealed that Vax2 is necessary for intraretinal pathfinding of retinal ganglion cells in mammals. These data demonstrate for the first time that Vax2 is both necessary and sufficient for the control of intraretinal RA metabolism, which in turn contributes to the appropriate expression of cone opsins in the vertebrate eye.
Prenatal Diagnosis of a Fetus with Terminal Deletion of Chromosome 1 (q43) in First-Trimester Screening: Is There a Characteristic Antenatal 1q Deletion Phenotype? A Case Report and Review of the Literature
2010-12-11

The terminal deletion of chromosome 1q is a disease of rare incidence. It might be hereditary or caused by spontaneous changes within the chromosome. Phenotypic characteristics including typical facial appearance, microcephaly, psychomotor retardation and variable other anomalies are suggested to be based on the loss of macrochromosomal materials within the long arm of chromosome 1. The number of symptoms is related to the loss of genetic material. To date, only very few cases of terminal 1q deletion syndrome have been diagnosed in utero, mainly after 20 weeks of gestation. Here, we present a case of del(1q)syndrome in a first-trimester fetus. Besides other structural anomalies of the fetus, prenatal ultrasound at 13 weeks’ gestation demonstrated severe microgenia and suspicion of cardiac defect. Chorionic villous sampling was performed, and cytogenetic analysis showed a de novo terminal chromosome 1 long arm deletion. We discuss the structural features of antenatally diagnosed fetuses with terminal deletion of chromosome 1 and try to give an answer to the question whether there is a characteristic antenatal 1q deletion phenotype.
The anatomy underlying acute versus chronic spatial neglect: a longitudinal study
2010-12-13

Our aim was to examine how brain imaging in the initial phase of a stroke could predict both acute/subacute as well as chronic spatial neglect. We present the first voxel-wise longitudinal lesion-behaviour mapping study, examining acute/subacute as well as chronic performance in the same individuals. Acute brain imaging (acquired on average 6.2 days post-injury) was used to evaluate neglect symptoms at the initial (mean 12.4 days post-stroke) and the chronic (mean 491 days) phase of the stroke. Chronic neglect was found in about one-third of the patients with acute neglect. Analysis suggests that lesion of the superior and middle temporal gyri predict both acute/subacute as well as chronic neglect. At the subcortical level, the basal ganglia as well as the inferior occipitofrontal fasciculus/extreme capsule appear to play a significant role for both acute/subacute as well as chronic neglect. Beyond, the uncinate fasciculus was critically related to the emergence of chronic spatial neglect. We infer that individuals who experience spatial neglect in the initial phase of the stroke yet do not have injury to these cortical and subcortical structures are likely to recover, and thus have a favourable prognosis.
Influence of Natural Organic Matter on As Transport and Retention
2010-12-13

Natural organic matter (NOM) can affect the behavior of arsenic within surface and subsurface environments. We used batch and column experiments to determine the effect of peat humic acids (PHA), groundwater fulvic acids (GFA), and a soil organic matter (SOM) extract on As sorption/transport in ferrihydrite-coated sand columns. A reactive transport model was used to quantitatively interpret the transport of As in flow-through column (breakthrough) experiments. We found that As(III) breakthrough was faster than As(V) by up to 18% (with OM) and 14% (without OM). The most rapid breakthrough occurred in systems containing SOM and GFA. Dialysis and ultrafiltration of samples from breakthrough experiments showed that in OM-containing systems, As was transported mostly as free (noncomplexed) dissolved As but also as ternary As-Fe-OM colloids and dissolved complexes. In OM-free systems, As was transported in colloidal form or as a free ion. During desorption, more As(III) desorbed (23-37%) than As(V) (10-16%), and SOM resulted in the highest and OM-free systems the lowest amount of desorption. Overall, our experiments reveal that (i) NOM can enhance transport/mobilization of As, (ii) different fractions of NOM are capable of As mobilization, and (iii) freshly extracted SOM (from a forest soil) had greater impact on As transport than purified GFA/PHA.
Light and heavy mesons in soft-wall holographic approach
2010-12-13

We study the spectrum and decay constants of light and heavy mesons in a soft-wall holographic approach, using the correspondence of string theory in Anti-de Sitter space and conformal field theory in physical space-time.
Prevention, Diagnosis, Therapy, and Follow-up of Lung Cancer
2010-12-14

This abridged version is based on an interdisciplinary guideline which corresponds to development stage 3 (S3) of guidelines according to the classification of the Association of the Scientific Medical Societies in Germany (AWMF). The guideline development process is characterized by the combination of formal evidence-search, formal consensus, logic (algorithms), decision and outcome analysis, and interdisciplinary development with the cooperation of 15 German and Austrian medical societies. [Table 1] shows the relationship between levels of evidence, consensus, and resulting recommendation grades of the recommendations of this guideline. The recommendation grades A – D are added to the recommendations in the abridged version. For the evidence levels, see the full version [1].
Cutting Edge: NKp80 Uses an Atypical Hemi-ITAM To Trigger NK Cytotoxicity
2010-12-14

Abstract The human NK cell receptor NKp80 stimulates cytotoxicity upon engagement of its genetically linked ligand AICL. However, the mechanisms underlying NKp80-mediated signaling are unknown. In this study, we dissected NKp80 signaling using the NK cell line NK92MI. We demonstrated that NKp80, but not NKp80 mutated at tyrosine 7 (NKp80/Y7F), is tyrosine phosphorylated. Accordingly, NKp80/Y7F, but not NKp80/Y30F or NKp80/Y37F, failed to induce cytotoxicity. NKp80 phosphopeptides comprising the hemi-ITAM–like sequence surrounding tyrosine 7 bound Lck- and Syk-family kinases; accordingly, cross-linking of NKp80, but not NKp80/Y7F, induced Syk phosphorylation. Moreover, inhibition of Syk kinase, but not ZAP-70 kinase, impaired cytotoxic responses through NKp80. Atypical residues in the hemi-ITAM–like motif of NKp80 cause an altered stoichiometry of phosphorylation but did not substantially affect NK cytotoxicity. Altogether, these results show that NKp80 uses an atypical hemi-ITAM and Syk kinase to trigger cellular cytotoxicity.
False-Positive Methadone Drug Screens During Quetiapine Treatment
2010-12-14

False-Positive Methadone Drug Screens During Quetiapine TreatmentTo the Editor: Quetiapine is a widely used antipsychotic and mood stabilizing compound.So far, false-positive methadone urine drug screens during quetiapine therapy have been described for 3 adults 1 and 12 adolescents. 2Here, we report a case series of 10 inpatients, 4 men and 6 women from 22 to 48 years old, suffering from mood or psychotic disorders who tested positive for methadone.Since such false-positive methadone screenings may seriously affect the therapeutic relationship, this potential interaction is highly relevant for clinicians.
Resistively shunted YBa2Cu3O7grain boundary junctions and low-noise SQUIDs patterned by a focused ion beam down to 80 nm linewidth
2010-12-15

YBa2Cu3O7 24° (30°) bicrystal grain boundary junctions (GBJs), shunted with 60 nm (20 nm) thick Au, were fabricated by focused ion beam milling with widths 80 nm ≤ w ≤ 7.8 μm. At 4.2 K we find critical current densities jc in the 105 A cm − 2 range (without a clear dependence on w) and an increase in resistance times junction area ρn with an approximate scaling . For the narrowest GBJs jcρn = IcRn≈100 μV (with critical current Ic and junction resistance Rn), which is promising for the realization of sensitive nanoSQUIDs for the detection of small spin systems. We demonstrate that our fabrication process allows the realization of sensitive nanoscale dc SQUIDs; for a SQUID with w≈100 nm wide GBJs we find an rms magnetic flux noise spectral density of SΦ1/2≈4 μΦ0 Hz − 1/2 in the white noise limit. We also derive an expression for the spin sensitivity Sμ1/2, which depends on SΦ1/2, on the location and orientation of the magnetic moment of a magnetic particle to be detected by the SQUID, and on the SQUID geometry. For the unoptimized SQUIDs presented here, we estimate Sμ1/2 = 390 μB Hz − 1/2, which could be further improved by at least an order of magnitude.
RULES FOR SUBATOMIC DERIVATION
2010-12-15

In proof-theoretic semantics the meaning of an atomic sentence is usually determined by a set of derivations in an atomic system which contain that sentence as a conclusion (see, in particular, Prawitz, 1971, 1973). The paper critically discusses this standard approach and suggests an alternative account which proceeds in terms of subatomic introduction and elimination rules for atomic sentences. A simple subatomic normal form theorem by which this account of the semantics of atomic sentences and the terms from which they are composed is underpinned, shows moreover that the proof-theoretic analysis of first-order logic can be pursued also beneath the atomic level.
Homoleptic Coinage Metal Compounds of Group(IV)heteroborates
2010-12-15

This article describes the synthesis and characterization of the first silver complex with the germylene [GeB11H11](2-) and coinage metal complexes with the stannylene ligand [SnB11H11](2-). Starting materials like CuCl, AuCl(Me2S), and AgNO3 were used to give mononuclear (3 and 4), dinuclear (5), hexanuclear (6), and heptanuclear (7) coordination compounds: [Et4N]5[Cu(CH3CN)(SnB11H11)3] (3), [Et4N]5[Ag(SnB11H11)3] (4), [Et4N]6[{Au(SnB11H11)2}2] (5), [Et4N]6[{Ag(GeB11H11)}6] (6), and [Et4N]9[Ag7(SnB11H11)8] (7). In case of the oligonuclear compounds 5-7 silver and gold aggregation was observed under formation of metal-metal bonds. Furthermore, the germa-closo-dodecaborate is found in a hitherto unknown μ3-bridging coordination mode connecting three silver atoms. The new compounds were characterized by single crystal X-ray diffraction and in the case of 3-6 also by NMR spectroscopy and elemental analysis.
Book reviews
2010-12-15

Click to increase image sizeClick to decrease image size Notes 1. P. Hall and C. Ward, Sociable Cities. The Legacy of Ebenezer Howard (Chichester: Wiley, 1988). 2. See Gibson‐Graham's 2003 discussion of ‘alternative economic spaces’; J.K. Gibson‐Graham, The End of Capitalism (As We Knew It) (Minneapolis, MN: University of Minnesota Press, 2006). 3. R. Hopkins, The Transition Handbook: From Oil Dependency to Local Resilience (Totnes: Green Books, 2008). 1. H. Ballon and K. Jackson, Robert Moses and the Modern City: The Transformation of New York (New York: W.W. Norton, 2007). 2. J. Jacobs, The Death and Life of Great American Cities (New York: Random House, 1961), here quoted from the edition Vintage Books Edition 1992. 3. The quote is included on the sleeve of later editions, e.g. the 1992 edition. 4. T. Mennel, J. Steffens, and Chr. Klemek, Block by Block, Jane Jacobs and the Future of New York (New York: Municipal Art Society of New York, Princeton Architectural Press, 2007). 5. B. Wellman, Jane Jacobs, the Torontonian, Centre for Urban Community Studies, Research Bulletin, 30 July 2006, 2. 6. A. Sparberg Alexiou, Jane Jacobs, Urban Visionary (Toronto: Harper Collins, 2007). 7. M. Allen, Ideas that Matter (Ontario: Ginger Press, 1997). 8. Ibid., xi. 9. R.A. Caro, The Power Broker. Robert Moses and the Fall of New York (New York: Vintage Books, 1975). 10. D. Schubert, ‘50 Jahre Jane Jacobs “Tod und Leben großer amerikanischer Städte” – Paradigmenwechsel in der Stadtplanung auf dem Weg zur erhaltenden Stadterneuerung’, in Die alte Stadt, ed. Arbeitsgemeinschaft Die alte Stadt, Vol. 37 (Weinstadt: BAG‐Publisher, 2011). 1. D.H. Meadows, The Limits to Growth: A Report for the Club of Rome's Project on the Predicament of Mankind (London: Earth Island, 1972). 2. N. Stern, The Economics of Climate Change. The Stern Review (Cambridge: CUP, 2006).
Soft-Gluon Resummation and the Valence Parton Distribution Function of the Pion
2010-12-16

We determine the valence parton distribution function of the pion by performing a new analysis of data for the Drell-Yan process π- N → μ+ μ- X. Compared to previous analyses, we include next-to-leading-logarithmic threshold resummation effects in the calculation of the Drell-Yan cross section. As a result of these, we find a considerably softer valence distribution at high momentum fractions x than obtained in previous next-to-leading-order analyses, in line with expectations based on perturbative-QCD counting rules or Dyson-Schwinger equations.
Use of 5-ALA fluorescence guided endoscopic biopsy of a deep-seated primary malignant brain tumor
2010-12-17

The introduction of fluorescence-guided resection of primary malignant brain tumors was a milestone in neurosurgery. Deep-seated malignant brain tumors are often not approachable for microsurgical resection. For diagnosis and therapy, new strategies are recommended. The combination of endoscopy and 5-aminolevulinic acid–induced protoporphyrin IX (5-ALA-induced Pp IX) fluorescence–guided procedures supported by neuronavigation seems an interesting option. Here the authors report on a combined approach for 5-ALA fluorescence–guided biopsy in which they use an endoscopy system based on an Xe lamp (excitation approximately λ = 407 nm; dichroic filter system λ = 380–430 nm) to treat a malignant tumor of the thalamus and perform a ventriculostomy and septostomy. The excitation filter and emission filter are adapted to ensure that the remaining visible blue remission is sufficient to superimpose on or suppress the excited red fluorescence of the endogenous fluorochromes. The authors report that the lesion was easily detectable in the fluorescence mode and that biopsy led to histological diagnosis.
Pyruvate Formate Lyase Acts as a Formate Supplier for Metabolic Processes during Anaerobiosis in Staphylococcus aureus
2010-12-18

ABSTRACT Previous studies demonstrated an upregulation of pyruvate formate lyase (Pfl) and NAD-dependent formate dehydrogenase (Fdh) in Staphylococcus aureus biofilms. To investigate their physiological role, we constructed fdh and pfl deletion mutants (Δ fdh and Δ pfl ). Although formate dehydrogenase activity in the fdh mutant was lost, it showed little phenotypic alterations under oxygen-limited conditions. In contrast, the pfl mutant displayed pleiotropic effects and revealed the importance of formate production for anabolic metabolism. In the pfl mutant, no formate was produced, glucose consumption was delayed, and ethanol production was decreased, whereas acetate and lactate production were unaffected. All metabolic alterations could be restored by addition of formate or complementation of the Δ pfl mutant. In compensation reactions, serine and threonine were consumed better by the Δ pfl mutant than by the wild type, suggesting that their catabolism contributes to the refilling of formyl-tetrahydrofolate, which acts as a donor of formyl groups in, e.g., purine and protein biosynthesis. This notion was supported by reduced production of formylated peptides by the Δ pfl mutant compared to that of the parental strain, as demonstrated by weaker formyl-peptide receptor 1 (FPR1)-mediated activation of leukocytes with the mutant. FPR1 stimulation could also be restored either by addition of formate or by complementation of the mutation. Furthermore, arginine consumption and arc operon transcription were increased in the Δ pfl mutant. Unlike what occurred with the investigated anaerobic conditions, a biofilm is distinguished by nutrient, oxygen, and pH gradients, and we thus assume that Pfl plays a significant role in the anaerobic layer of a biofilm. Fdh might be critical in (micro)aerobic layers, as formate oxidation is correlated with the generation of NADH/H + , whose regeneration requires respiration.
Equivalent Neurogenic Potential of Wild-Type and GFP-Labeled Fetal-Derived Neural Progenitor Cells Before and After Transplantation Into the Rodent Hippocampus
2010-12-18

GFP-transgenic cells represent an important tool in transplantation studies. Herein, we demonstrate their ability to generate functional neurons both in vitro and in vivo conditions. Neurons derived from fetal NPCs were able to integrate into the normal hippocampal circuitry. The high yield of mature neurons generated render these cells important candidates for restorative approaches based on cell therapy.
Functional Detrusor Myoplasty for Bladder Acontractility: Long-Term Results
2010-12-19

The results of this multicenter analysis demonstrate that latissimus dorsi detrusor myoplasty is an effective alternative to clean intermittent catheterization in a select group of patients with neurogenic bladder acontractility.
Adolescence As Risk Factor for Adverse Pregnancy Outcome in Central Africa – A Cross-Sectional Study
2010-12-20

Our data demonstrate the importance of adolescent age as risk factor for adverse pregnancy outcome. Antenatal care programs specifically tailored for the needs of adolescents may be necessary to improve the frequency of antenatal care visits and pregnancy outcomes in this risk group in Central Africa.