julilili42/papers huggingface dataset:
Comparative morphology of the tentorium and hypopharyngeal–premental sclerites in sporophagous and non‐sporophagous adult Aleocharinae (Coleoptera: Staphylinidae)
2012-12-10

Abstract We elucidate the configuration of the tentorium and the sclerites of the hypopharynx–prementum complex in selected spore‐ (pollen‐) and non‐spore‐feeding Aleocharinae (Staphylinidae) by presenting the first comparative 3D reconstructions of these structures for 19 staphylinoid beetle species (six outgroups, 13 Aleocharinae). General organization of the tentorium follows the groundplan previously proposed for adult Staphylinidae, although some taxa have reduced or lost the dorsal (all Aleocharinae studied, Agathidium mandibulare [Leiodidae]) or anterior ( Omalium rivulare [Omaliinae], Anotylus sculpturatus [Oxytelinae]) tentorial arms. All species investigated have premental and hypopharyngeal sclerites that are partly homologizable across taxa. We clarified that Musculus praementopalpalis externus originates from the premental sclerite, resolving its unclear origin reported in our previous publications. Eight of 13 investigated Aleocharinae species are spore/pollen feeders, six obligatorily. Three of these six ( Eumicrota , Gyrophaena fasciata , G. gentilis ) have grinding pseudomolae and a fully developed hypopharyngeal suspensorium with posterior bridge and anterior elongations; the remaining three ( Oxypoda, Pagla, Polylobus ) lack pseudomolae and suspensorial bridge, but have the suspensorium elongated anteriorly. The dorsolateral side of the hypopharyngeal sclerite interacts with the pseudomola. Obligate sporophagy/pollinivory apparently arose at least three times in Aleocharinae, not always involving the pseudomola–hypopharynx grinding mechanism.
The intra-observer reproducibility of cardiovascular magnetic resonance myocardial feature tracking strain assessment is independent of field strength
2012-12-11

CMR-FT results are similar with reasonable intra-observer reproducibility in different groups of volunteers at 1.5 T and 3T. CMR-FT is a promising novel technique and our data indicate that results might be transferable between field strengths. However there is a considerable amount of segmental variability indicating that further refinements are needed before CMR-FT can be fully established in clinical routine for quantitative assessment of wall mechanics and strain.
Atg18 function in autophagy is regulated by specific sites within its β-propeller
2012-12-11

Summary Autophagy is a conserved degradative transport pathway. It is characterized by the formation of double-membrane autophagosomes at the phagophore assembly site (PAS). Atg18 is essential for autophagy but also for vacuole homeostasis and probably endosomal functions. This protein is basically a β-propeller, formed by seven WD40 repeats, that contains a conserved FRRG motif that binds to phosphoinositides and promotes Atg18 recruitment to the PAS, endosomes and vacuoles. However, it is unknown how Atg18 association with these organelles is regulated, as the phosphoinositides bound by this protein are present on the surface of all of them. We have investigated Atg18 recruitment to the PAS and found that Atg18 binds to Atg2 through a specific stretch of amino acids in the β-propeller on the opposite surface to the FRRG motif. As in the absence of the FRRG sequence, the inability of Atg18 to interact with Atg2 impairs its association with the PAS, causing an autophagy block. Our data provide a model whereby the Atg18 β-propeller provides organelle specificity by binding to two determinants on the target membrane.
In vitro antimicrobial sperm protection by an ejaculate‐like substance
2012-12-11

Summary Ejaculate substances are hugely diverse among and within species. The functional significance of this diversity has been little studied except for a few accessory gland proteins. These studies suggest that ejaculate components evolve mainly by sexual selection, that is, sperm competition, male–female co‐evolution or by female choice for paternal investment. However, male benefits of protecting sperm from microbial harm, that is, antimicrobial ejaculate protection, has received little attention in the evolutionary literature, while it has been discussed in the human and livestock literature. Here, we examine in the common bedbug, C imex lectularius , the two basic components of the antimicrobial ejaculate protection hypothesis: 1) microbes damage sperm cells and 2) antimicrobial ejaculate substances prevent such microbe‐induced sperm damage. We found that environmental microbes, which are sexually transmitted in bedbugs, induce sperm mortality. Sperm mortality was high (increased 40% compared with controls without bacteria) and very rapid (within 10 min) in vitro . Consistent with the antimicrobial sperm protection hypothesis, a lysozyme dose equivalent to the amount of antibacterial lysozyme‐like activity that is transferred in the seminal fluid during a single mating was sufficient to reduce sperm mortality to control levels. While this result is not necessarily predicted by the paternal investment hypothesis, it is plausible that female benefits of male immune substances may evolve under the male–female co‐evolution hypothesis. We found that weekly physiological lysozyme doses equivalent to the observed lysozyme‐like activity in seminal fluid benefit females to some extent, indicating that immune‐active ejaculate substances may have a secondary gift function and may release females from a trade‐off between reproduction and immunity. Lysozyme seems to stimulate early egg‐laying above the female optimum and later cause earlier reproductive senescence, which is not consistent with the idea of an overall direct benefit but is consistent with the idea that males transfer manipulative substances to the females. Our data are consistent with antimicrobial sperm protection. They support the idea of a naturally selected origin of ejaculate components and provide a mechanistically well‐defined pathway how sexual selection can affect ejaculate composition via antimicrobial sperm protection. As sperm and microbes frequently encounter each other in many species, antimicrobial sperm protection may be a common phenomenon and has the potential to inform models of male and female co‐evolution and biological diversification.
Training in virtual environments: putting theory into practice
2012-12-11

Feeling of presence, social context, learning motivation and perspective-taking are relevant for training in virtual environments. The theory-into-practice framework presented here supports developers and trainers in implementing virtual training tools. The framework was validated with an interview study of stakeholders of a virtual training project. We identified limitations, opportunities and challenges.
Development of the mammalian axial skeleton requires signaling through the Gα i subfamily of heterotrimeric G proteins
2012-12-11

129/SvEv mice with a loss-of-function mutation in the heterotrimeric G protein α-subunit gene Gnai3 have fusions of ribs and lumbar vertebrae, indicating a requirement for Gα i (the “inhibitory” class of α-subunits) in somite derivatives. Mice with mutations of Gnai1 or Gnai2 have neither defect, but loss of both Gnai3 and one of the other two genes increases the number and severity of rib fusions without affecting the lumbar fusions. No myotome defects are observed in Gnai3 / Gnai1 double-mutant embryos, and crosses with a conditional allele of Gnai2 indicate that Gα i is specifically required in cartilage precursors. Penetrance and expressivity of the rib fusion phenotype is altered in mice with a mixed C57BL/6 × 129/SvEv genetic background. These phenotypes reveal a previously unknown role for G protein-coupled signaling pathways in development of the axial skeleton.
Targeting hyperactivation of the AKT survival pathway to overcome therapy resistance of melanoma brain metastases
2012-12-12

Abstract Brain metastases are the most common cause of death in patients with metastatic melanoma, and the RAF ‐ MEK ‐ ERK and PI3K‐ AKT signaling pathways are key players in melanoma progression and drug resistance. The BRAF inhibitor vemurafenib significantly improved overall survival. However, brain metastases still limit the effectiveness of this therapy. In a series of patients, we observed that treatment with vemurafenib resulted in substantial regression of extracerebral metastases, but brain metastases developed. This study aimed to identify factors that contribute to treatment resistance in brain metastases. Matched brain and extracerebral metastases from melanoma patients had identical ERK , p‐ ERK , and AKT immunohistochemistry staining patterns, but there was hyperactivation of AKT (p‐ AKT ) and loss of PTEN expression in the brain metastases. Mutation analysis revealed no differences in BRAF , NRAS , or KIT mutation status in matched brain and extracerebral metastases. In contrast, AKT , p‐ AKT , and PTEN expression was identical in monolayer cultures derived from melanoma brain and extracerebral metastases. Furthermore, melanoma cells stimulated by astrocyte‐conditioned medium showed higher AKT activation and invasiveness than melanoma cells stimulated by fibroblast‐conditioned medium. Inhibition of PI3K‐ AKT signaling resensitized melanoma cells isolated from a vemurafenib‐resistant brain metastasis to vemurafenib. Brain‐derived factors appear to induce hyperactivation of the AKT survival pathway and to promote the survival and drug resistance of melanoma cells in the brain. Thus, inhibition of PI3K‐ AKT signaling shows potential for enhancing and/or prolonging the antitumor effect of BRAF inhibitors or other anticancer agents in melanoma brain metastases.
Results of a double-blind, placebo-controlled pharmacotherapy trial in alcoholism conducted in Germany and comparison with the US COMBINE study
2012-12-12

The results of placebo-controlled trials (RCTs) with acamprosate or naltrexone vary substantially. Those differences have been attributed to differing patient characteristics, recruitment strategies, treatment settings and remuneration systems. We tested these assumptions by comparing a new double-blind, placebo-controlled randomized trial conducted in Germany (called PREDICT Study) with data from the US COMBINE Study. PREDICT was designed according to the protocol of the COMBINE Study. A total of 426 alcohol-dependent patients were compared to 459 COMBINE Study patients corresponding to the treatment cells in PREDICT. All patients received acamprosate, naltrexone or placebo for 3 months (PREDICT) or 4 months (COMBINE). Biweekly manualized 'medical management' to enhance compliance was delivered in both studies. Time until the first occurrence of heavy drinking was the main outcome measure. PREDICT found neither acamprosate nor naltrexone to supply any additional benefit compared with placebo, which is at variance with a positive naltrexone effect being reported in the COMBINE Study. A secondary comparison between both studies showed better overall treatment outcomes in PREDICT, although these patients had been more severely affected than their COMBINE counterparts. The divergence in results may be attributable to basic differences in the treatment environments (such as in-patient pre-treatment versus primary outpatient care). We suggest that identically designed RCTs conducted in different parts of the world may help improve the external validity of RCTs. This approach could be called 'comparative efficacy research'.
Stratification, superfluidity and magnetar QPOs
2012-12-12

The violent giant flares of magnetars excite QPOs which persist for hundreds of seconds, as seen in the X-ray tail following the initial burst. Recent studies, based on single-fluid barotropic magnetar models, have suggested that the lower-frequency QPOs correspond to magneto-elastic oscillations of the star. The higher frequencies, however, in particular the strong 625 Hz peak, have proved harder to explain, except as high mode multipoles. In this work we study the time evolutions of non-axisymmetric oscillations of two-fluid Newtonian magnetars with no crust. We consider models with superfluid neutrons and normal protons, and poloidal and toroidal background field configurations. We show that multi-fluid physics (composition-gradient stratification, entrainment) tends to increase Alfven mode frequencies significantly from their values in a single-fluid barotropic model. The higher-frequency magnetar QPOs may then be naturally interpreted as Alfven oscillations of the multi-fluid stellar core. The lower-frequency QPOs are less easily explained within our purely fluid core model, but we discuss the possibility that these are crustal modes.
Ecological change in the lower Omo Valley around 2.8 Ma
2012-12-12

Late Pliocene climate changes have long been implicated in environmental changes and mammalian evolution in Africa, but high-resolution examinations of the fossil and climatic records have been hampered by poor sampling. By using fossils from the well-dated Shungura Formation (lower Omo Valley, northern Turkana Basin, southern Ethiopia), we investigate palaeodietary changes in one bovid and in one suid lineage from 3 to 2 Ma using stable isotope analysis of tooth enamel. Results show unexpectedly large increases in C 4 dietary intake around 2.8 Ma in both the bovid and suid, and possibly in a previously reported hippopotamid species. Enamel δ 13 C values after 2.8 Ma in the bovid ( Tragelaphus nakuae ) are higher than recorded for any living tragelaphin, and are not expected given its conservative dental morphology. A shift towards increased C 4 feeding at 2.8 Ma in the suid ( Kolpochoerus limnetes ) appears similarly decoupled from a well-documented record of dental evolution indicating gradual and progressive dietary change. The fact that two, perhaps three, disparate Pliocene herbivore lineages exhibit similar, and contemporaneous changes in dietary behaviour suggests a common environmental driver. Local and regional pollen, palaeosol and faunal records indicate increased aridity but no corresponding large and rapid expansion of grasslands in the Turkana Basin at 2.8 Ma. Our results provide new evidence supporting ecological change in the eastern African record around 2.8 Ma, but raise questions about the resolution at which different ecological proxies may be comparable, the correlation of vegetation and faunal change, and the interpretation of low δ 13 C values in the African Pliocene.
Trends in Childhood Tuberculosis in Zambia: A Situation Analysis
2012-12-12

Childhood TB is an important but neglected problem in Zambia highlighted by the fact that no data exists on HIV co-infection and MDR-TB. Strengthening of the National TB Programme and diagnostics services/algorithms are required to accurately define the TB burden, HIV co-infection and MDR-TB rates in children in Zambia.
Pulsar Glitches: The Crust is not Enough
2012-12-13

Pulsar glitches are traditionally viewed as a manifestation of vortex dynamics associated with a neutron superfluid reservoir confined to the inner crust of the star. In this Letter we show that the nondissipative entrainment coupling between the neutron superfluid and the nuclear lattice leads to a less mobile crust superfluid, effectively reducing the moment of inertia associated with the angular momentum reservoir. Combining the latest observational data for prolific glitching pulsars with theoretical results for the crust entrainment, we find that the required superfluid reservoir exceeds that available in the crust. This challenges our understanding of the glitch phenomenon, and we discuss possible resolutions to the problem
Measurement of the extragalactic background light imprint on the spectra of the brightest blazars observed with H.E.S.S.
2012-12-13

The extragalactic background light (EBL) is the diffuse radiation with the second highest energy density in the Universe after the cosmic microwave background. The aim of this study is the measurement of the imprint of the EBL opacity to gamma-rays on the spectra of the brightest extragalactic sources detected with the High Energy Stereoscopic System (H.E.S.S.). The originality of the method lies in the joint fit of the EBL optical depth and of the intrinsic spectra of the sources, assuming intrinsic smoothness. Analysis of a total of [aprox]105gamma-ray events enables the detection of an EBL signature at the 8.8sigma level and constitutes the first measurement of the EBL optical depth using very-high energy (E &gt; 100 GeV) gamma-rays. The EBL flux density is constrained over almost two decades of wavelengths [0.30 mum, 17 mum] and the peak value at 1.4 mum is derived as lambdaFlambda = 15 ± 2stat ± 3sys nW m-2 sr-1. Appendix A is available in electronic form at http://www.aanda.org
Variable pulse profiles of Hercules X-1 repeating with the same irregular 35 d clock as the turn-ons
2012-12-13

\\n The accreting X-ray pulsar Her X-1 shows two types of long-term variations, both with periods of ~35 days: 1) turn-on cycles, a modulation of the flux, with a ten-day long main-on and a five-day long short-on, separated by two off-states, and 2) a systematic variation in the shape of the 1.24 s pulse profile. While there is general consensus that the flux modulation is due to variable shading of the X-ray emitting regions on the surface of the neutron star by the precessing accretion disk, the physical reason for the variation in the pulse profiles has remained controversial. Following the suggestion that free precession of the neutron star may be responsible for the variation in the pulse profiles, we developed a physical model of strong feedback interaction between the neutron star and the accretion disk in order to explain the seemingly identical values for the periods of the two types of variations, which were found to be in basic synchronization. In a deep analysis of pulse profiles observed by several different satellites over the last three decades we now find that the clock behind the pulse profile variations shows exactly the same erratic behavior as the turn-on clock, even on short time scales (a few 35 d cycles), suggesting that there may in fact be only one 35 d clock in the system. If this is true, it raises serious questions with respect to the idea of free precession of the neutron star, namely how the neutron star can change its precessional period every few years by up to 2.5% and how the feedback can be so strong, such that these changes can be transmitted to the accretion disk on rather short time scales. \\n
Phase II study of central nervous system (CNS)-directed chemotherapy including high-dose chemotherapy with autologous stem cell transplantation for CNS relapse of aggressive lymphomas
2012-12-14

The prognosis of patients with central nervous system relapse of aggressive lymphoma is very poor with no therapy established so far. In a prospective multicenter phase II study, we evaluated a potentially curative chemotherapy-only regimen in these patients. Adult immunocompetent patients 65 years of age or under received induction chemotherapy with MTX/IFO/DEP (methotrexate 4 g/m(2) intravenously (i.v.) Day 1, ifosfamide 2 g/m(2) i.v. Days 3- 5 and liposomal cytarabine 50 mg intrathecally (i.th) Day 6) and AraC/TT/DEP (cytarabine 3g/m(2) i.v. Days 1-2, thiotepa 40 mg/m(2) i.v. Day 2 and i.th. liposomal cytarabine 50 mg i.th. Day 3) followed by high-dose chemotherapy with carmustine 400 mg/m(2) i.v. Day -5, thiotepa 2×5 mg/kg i.v. Days -4 to -3 and etoposide 150 mg/m(2) i.v. Days -5 to -3, and autologous stem cell transplantation Day 0 (HD-ASCT). Thirty eligible patients (median age 58 years) were enrolled. After HD-ASCT (n=24), there was a complete remission in 15 (63%), partial remission in 2 (8%) and progressive disease in 7 (29%) patients. Myelotoxicity was the most adverse event with CTC grade 3/4 infections in 12% of MTX/IFO/DEP courses, 21% of AraC/TT/DEP courses and 46% of HD-ASCT courses. The 2-year time to treatment failure was 49%±19 for all patients and 58%±22 for patients completing HD-ASCT. The protocol assessed proved feasible and highly active with long-lasting remissions in a large proportion of patients. (ClinicalTrials.govIdentifier NCT01148173).
Pliocene-Pleistocene Climate Change At the NE Tibetan Plateau Deduced From Lithofacies Variation In the Drill Core SG-1, Western Qaidam Basin, China
2012-12-14

The Pliocene-Pleistocene sedimentologic evolution of the western Qaidam Basin at the NE Tibetan Plateau was studied on the nearly thousand-meter-deep drill core SG-1 (spanning ca. 2.8-0.1 Ma), recovered from the Chahansilatu sub-depression with an average recovery rate of 95%. Lithofacies variation records the regional climatic change in relation to Asian drying and Tibetan Plateau uplift. Sedimentary textures and structures demonstrate a continuous slight coarsening and an increase of evaporites upward. We recognized five lithofacies: (1) gray-black laminated mudstone, (2) gray massive mudstone and siltstone, (3) bedded halite, (4) loose muddy halite, and (5) brownish-yellowish saliferous siltstone and mudstone, representing (1) semi-deep fresh to semi-brackish lake, (2) shallow brackish lake, (3) perennial saline lake, (4) playa saline lake, and (5) saline mudflat conditions, respectively. Variation of the lithofacies through the core demonstrates a clear trend of lake shrinkage since the late Pliocene and the final termination of the Chahansilatu paleolake. Accelerations of lake shrinkages are observed at ca. 2.5 Ma, 2.2 Ma, 1.6 Ma, 1.2 Ma, 0.9 Ma, 0.6 Ma, and 0.1 Ma. Our results suggest that the long-term stepwise drying of the Asian inland may have been forced by the change of the global ice volume.
In Vitro Comparison of Hypericin and 5-Aminolevulinic Acid-Derived Protoporphyrin IX for Photodynamic Inactivation of Medulloblastoma Cells
2012-12-14

By its 5-fold increase in fluorescence over autofluorescence levels HYP has excellent properties for tumor visualization in medulloblastomas. The high photocytotoxicity of HYP, compared to 5-ALA-derived PpIX, is convincingly demonstrated by its 8- to 13-fold lower LD50. Therefore HYP might be a promising molecule for intraoperative visualization and photodynamic treatment of medulloblastomas.
Heavy metal pollution in farmland irrigated with river water near a steel plant—magnetic and geochemical signature
2012-12-14

The presence of heavy metals (HMs) in the environment is a major threat for humans. Magnetic proxies provide a rapid method for assessing the degree of HM pollution in environment. We have studied farmland soil irrigated with polluted river water in the vicinity of a steel plant in Loudi city (Hunan Province, China) to test the efficiency of magnetic methods for detecting the degree of HM pollution. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these farmland soils. Enhanced magnetic concentration values were found in the upper arable soil horizon (0–20 cm), which is related to the presence of spherical ∼10 to 30 μm sized magnetite particles. The spatial distribution of magnetic concentration and HM contents in the farmland soils matches with the spatial pattern of these parameters in river sediments. These findings provide evidence that HM pollution of the farmland soil is mainly caused by irrigation with wastewater. HMs Zn, Pb, Cu, Cd, Co, Ni, V are well correlate with magnetic susceptibility (χ). The pollution load index (PLI) of all nine anthropogenic HMs (including also Cr and Mo) and log10(χ) are significantly correlated. Using the resulting linear PLI−log10(χ) function, values of χ can serve as a convenient tool for semi-quantifying the degree of HM pollution in the uppermost ∼20 cm of the studied farmland soils. These findings suggest that magnetic methods can generally serve as a convenient tool for detecting and mapping HM pollution in farmland soil irrigated with wastewater from sites nearby heavy industrial activities.