463 research outputs found

    Geology of high- to ultrahigh-temperature granulites from central Madurai block, southern India ; with emphasis on the evolution of Grt-Opx-Crd granulite

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    The geology of Ganguvapatti area situated at the central Madurai block of southern India consisting of varous high-grade metamorphic rock types. This contribution briefly describes the geology, field occurrences and petrography of metamorphic rock from Ganguvarpatti area. Ganguvarpatti is known for its occurrence of sapphirine-bearing UHT granulites while the surrounding granulites are less studied. So in this contribution we have discussed the pressure-temperature stability and evolution of granulites surrounding UHT granulites. The pressure-temperature estimation of garnet-orthopyroxene-cordierite granulite resulted a near peak temperature condition of>950゜ C at a pressure between 9-10 kbar. These results are in good agreement with the stability field in the KFMASH petrogenetic frid

    TEMPERATURE EFFECT ON THE STRENGTH OF ADHESIVELY BONDED SINGLE LAP JOINTS

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    The purpose of this paper is to study some of the factors that affect the shear strength of Single Lap Joints (SLJ). Based in work conditions for different applications, tests were made in order to define the influence of geometry and temperature on the strength of SLJ under shear load. The adhesive used to make the joints was the epoxy adhesive ARC858 and it was tested under temperatures ranging between 21°C and 70°C and overlap length of 12.5mm and 18.75mm. Results of those tests showed that shear strength increased due to geometry with an overlap of 18.75mm and a great shear strength loss ranging from 30°C to 50°C. The failure mechanism was adhesive failure

    High-efficiency pharmacogenetic ablation of oligodendrocyte progenitor cells in the adult mouse CNS

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    Approaches to investigate adult oligodendrocyte progenitor cells (OPCs) by targeted cell ablation in the rodent CNS have limitations in the extent and duration of OPC depletion. We have developed a pharmacogenetic approach for conditional OPC ablation, eliminating >98% of OPCs throughout the brain. By combining recombinase-based transgenic and viral strategies for targeting OPCs and ventricular-subventricular zone (V-SVZ)-derived neural precursor cells (NPCs), we found that new PDGFRA-expressing cells born in the V-SVZ repopulated the OPC-deficient brain starting 12 days after OPC ablation. Our data reveal that OPC depletion induces V-SVZ-derived NPCs to generate vast numbers of PDGFRA+NG2+ cells with the capacity to proliferate and migrate extensively throughout the dorsal anterior forebrain. Further application of this approach to ablate OPCs will advance knowledge of the function of both OPCs and oligodendrogenic NPCs in health and disease

    Responses of the soil microbial community to nitrogen fertilizer regimes and historical exposure to extreme weather events : flooding or prolonged-drought

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    Extreme weather events, including flooding and prolonged-drought, may establish long-lasting effects on soil biotic and abiotic properties, thus influencing ecosystem functions including primary productivity in subsequent years. Nitrogen (N) fertilizer addition often improves soil fertility, thereby potentially alleviating legacy effects on soil function and plant productivity. The soil microbial community plays a central role in mediating soil functioning; however, little is known about the legacy impacts of extreme weather events and N fertilizer addition on soil bacterial communities and the key processes involved in carbon (C) cycling. Here, the potential legacy effects of waterlogging, prolonged-drought and N fertilizer addition (0, 100, 200 and 300 kg N/ha) on soil bacteria and microbial respiration were investigated. The abundance, diversity and composition of the bacterial community, and basal and induced-respiration rates, in a farming soil system were examined, using quantitative PCR, high-throughput DNA sequencing, and MicroResp™. Soils previously exposed to short-term waterlogging events and prolonged-drought (by air-drying for 4 months) were used in our study. Prolonged drought, but not waterlogging, had a strong legacy effect on the soil bacterial community and microbial respiration. The addition of N fertilizer up to 300 kg N/ha could not fully counteract the legacy effects of prolonged-drought on soil bacteria. However, N addition did increase bacterial abundance and diversity, and inhibited soil microbial respiration. Significant correlations between microbial respiration and bacterial community structure were observed, but N addition weakened these relationships. Our results suggest that the resilience (rate of recovery) of soil bacterial communities and functions to prolonged-drought is limited in farming systems, and therefore, may take a long time to recover completely. Subsequently, this should be explicitly considered when developing adaptation strategies to alleviate the impacts of extreme weather events

    Atypical disengagement from faces and its modulation by the control of eye fixation in children with Autism Spectrum Disorder

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    By using the gap overlap task, we investigated disengagement from faces and objects in children (9–17 years old) with and without autism spectrum disorder (ASD) and its neurophysiological correlates. In typically developing (TD) children, faces elicited larger gap effect, an index of attentional engagement, and larger saccade-related event-related potentials (ERPs), compared to objects. In children with ASD, by contrast, neither gap effect nor ERPs differ between faces and objects. Follow-up experiments demonstrated that instructed fixation on the eyes induces larger gap effect for faces in children with ASD, whereas instructed fixation on the mouth can disrupt larger gap effect in TD children. These results suggest a critical role of eye fixation on attentional engagement to faces in both groups

    Transesterification of PHA to Oligomers Covalently Bonded with (Bio)Active Compounds Containing Either Carboxyl or Hydroxyl Functionalities

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    © 2015 The Authors. Published by Public Library of Science. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0120149This manuscript presents the synthesis and structural characterisation of novel biodegradable polymeric controlled-release systems of pesticides with potentially higher resistance to weather conditions in comparison to conventional forms of pesticides. Two methods for the preparation of pesticide-oligomer conjugates using the transesterification reaction were developed. The first method of obtaining conjugates, which consist of bioactive compounds with the carboxyl group and polyhydroxyalkanoates (PHAs) oligomers, is "one-pot" transesterification. In the second method, conjugates of bioactive compounds with hydroxyl group and polyhydroxyalkanoates oligomers were obtained in two-step method, through cyclic poly(3-hydroxybutyrate) oligomers. The obtained pesticide-PHA conjugates were comprehensively characterised using GPC, 1H NMR and mass spectrometry techniques. The structural characterisation of the obtained products at the molecular level with the aid of mass spectrometry confirmed that both of the synthetic strategies employed led to the formation of conjugates in which selected pesticides were covalently bonded to PHA oligomers via a hydrolysable ester bond

    Stromal micropapillary pattern predominant lung adenocarcinoma - a report of two cases

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    Generally, adenocarcinomas with micropapillary pattern, featuring small papillary tufts lacking a central fibrovascular core, are thought to have poor prognosis. This pattern has been described in various organs. However, tumor cells with micropapillary pattern of lung adenocarcinoma are more often seen to float within alveolar spaces (aerogenous micropapillary pattern, AMP) than in fibrotic stroma like other organs (stromal micropapillary pattern, SMP) and SMP predominant lung adenocarcinoma (SMPPLA) has not been well described yet. We presented two cases of SMPPLA which were found in the last four years. Both the cases showed more than 50% of SMP in the tumor area. The majority of the stromal micropapillary clusters expressed MUC1 and epithelial membrane antigen along the outer surface of cell membrane. On the other hand, connective tissues surrounding stromal micropapillary clusters showed no reactivity for epithelial markers (thyroid transcription factor-1 and cytokeratin) or endothelial marker (D2-40 and CD34). It means clusters of SMP do not exist within air space or lymphatic or vessel lumens. The tumors with SMP often presented lymphatic permeation and vessel invasion, and intriguingly, one of the two cases showed metastasis to the mediastinal lymph node. Additionally, both the cases showed EGFR point mutations of exon 21. These results suggest that SMPPLA might be associated with poor prognosis and effective for EGFR tyrosine kinase inhibitors
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