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Proceedings of IEEE RCIS 2015: 9th International Conference on Challenges in Information Science
No full textAdvances in synchrotron x-ray diffraction and transmission electron microscopy techniques for the investigation of microstructure evolution in proton-and neutron-irradiated zirconium alloys
No full textABSTRACT Transmission electron microscopy (TEM) studies provide mechanistic understanding of nanoscale processes, whereas advanced synchrotron XRD (SXRD) enables precise measurements on volumes that are more representative of bulk materials. Therefore, the combined strengths of these techniques can provide new insight into irradiation-induced mechanistic processes. In the present study, their application to Zircaloy-2, proton-irradiated to 2.3, 4.7, and 7.0 dpa at 2 MeV and 350 ??C and neutron-irradiated to 9.5 and 13.1 ?? 1025 n m???2 are exemplified. The application of correlative spectral imaging and structural TEM investigations to the phase transformation of Zr(Fe,Nb)2 precipitates in Low-Sn ZIRLO???, neutron-irradiated to 8.9???9 ?? 1025 n m???2, demonstrates the possibility of a Cr core nucleation site. Anomalous broadening is observed in SXRD profiles, which is believed to be caused by defect clusters and precursors to dislocation loop nucleation. The challenges to quantitative analysis of dislocations by SXRD are highlighted with reference to the segregation of Fe and Ni to basal planes and dislocation cores, observed by spectral imaging in the TEM
Development of thymic Foxp3(+) regulatory T cells: TGF-β matters.
No full textCD4(+) regulatory T cells expressing the transcription factor Foxp3 can be generated in the thymus (tTreg cells), but the cellular and molecular pathways driving their development remain incompletely understood. TGF-β is essential for the generation of Foxp3(+) Treg cells converted from peripheral naïve CD4(+) T cells (pTreg cells), yet a role for TGF-β in tTreg-cell development was initially refuted. Nevertheless, recent studies have unmasked a requirement for TGF-β in the generation of tTreg cells. Experimental evidence reveals that TGF-β in the context of TCR stimulation induces Foxp3 gene transcription in thymic Treg precursors, CD4(+) CD8(-) CD25(-) semimature and mature single-positive thymocytes. Intriguingly, thymic apoptosis was found to be intrinsically linked to the generation of tTreg cells, as apoptosis induced expression of TGF-β intrathymically. In this short review, we will highlight key data, discuss the experimental evidence and propose a modified model of tTreg-cell development involving TGF-β. We will also outline the remaining unresolved questions concerning generation of thymic Foxp3(+) Treg cells and provide our personal perspectives on the mechanisms controlling tTreg-cell development
Efficacy and safety of nebulised amphotericin B (NAB) in severe asthma with fungal sensitisation (SAFS) and allergic bronchopulmonary aspergillosis (ABPA).
No full textBACKGROUND AND RATIONALE: Antifungal therapy for severe asthma with fungal sensitisation (SAFS) and allergic bronchopulmonary aspergillosis (ABPA) remains poorly studied. We assessed the efficacy and safety of NAB as second and third line therapy in SAFS and ABPA. METHODS: 21 adult asthmatics with SAFS (n = 11) and ABPA (n = 10) who had either failed itraconazole (n = 8), voriconazole proceeded by itraconazole (n = 5) or developed adverse events (AEs) to either agent (n = 7) were treated with 10mg of NAB (Fungizone) twice daily. We audited clinical and immunological response, using the Asthma Quality of Life Questionnaire (AQLQ-J) scores, asthma control, FEV1, healthcare utilisation and IgE. Patients were followed up for 12 months. RESULTS: Twenty-one patients were treated (SAFS, n = 11) and (ABPA, n = 10), M: F = 8:12, median age 65 years (range, 24-78). The median duration of therapy was 30 days (0-1825). Clinical benefit was observed in three (14.3 %) in which overall mean AQLQ-J score improved by + 2.9, mean FEV1 improved by 0.5 L and there was improvement in overall asthma control. Seven (33%) failed initial dose (bronchospasm). Eleven (52.4%) discontinued within 12 months of therapy due to delayed bronchospasm (n = 3, within 4 weeks), equipment problems (n = 2, within 4 weeks) and lack of clinical benefit (n = 4, within 16 weeks). CONCLUSION: Our data suggest that the overall efficacy of NAB in this group of patients is poor and associated with bronchospasm. However, the excellent response in 3 patients, suggest it may be considered when other alternatives have been exhausted. Overcoming the initial bronchospasm may improve tolerability
Brothers Grimm or Brothers Karamazov: The Myth and the Reality of How Russians and Ukrainians View the Other
No full textMulti-stage genome-wide association study identifies new susceptibility locus for testicular germ cell tumour on chromosome 3q25
No full textRecent genome-wide association studies (GWAS) and subsequent meta-analyses have identified over 25 SNPs at 18 loci, together accounting for >15% of the genetic susceptibility to testicular germ cell tumour (TGCT). To identify further common SNPs associated with TGCT, here we report a three-stage experiment, involving 4098 cases and 18 972 controls. Stage 1 comprised previously published GWAS analysis of 307 291 SNPs in 986 cases and 4946 controls. In Stage 2, we used previously published customised Illumina iSelect genotyping array (iCOGs) data across 694 SNPs in 1064 cases and 10 082 controls. Here, we report new genotyping of eight SNPs showing some evidence of association in combined analysis of Stage 1 and Stage 2 in an additional 2048 cases of TGCT and 3944 controls (Stage 3). Through fixed-effects meta-analysis across three stages, we identified a novel locus at 3q25.31 (rs1510272) demonstrating association with TGCT [per-allele odds ratio (OR) = 1.16, 95% confidence interval (CI) = 1.06-1.27; P = 1.2 x 10(-9)]
Oculo-auriculo-vertebral spectrum: clinical and molecular analysis of 51 patients.
No full textINTRODUCTION: Oculo-auriculo-vertebral spectrum (OAVS OMIM 164210) is a craniofacial developmental disorder affecting the development of the structures derived from the 1st and the 2nd branchial arches during embryogenesis, with consequential maxillary, mandibular, and ear abnormalities. The phenotype in OAVS is variable and associated clinical features can involve the cardiac, renal, skeletal, and central nervous systems. Its aetiology is still poorly understood. METHODS: We have evaluated the clinical phenotypes of 51 previously unpublished patients with OAVS and their parents, and performed comparative genomic hybridization microarray studies to identify potential causative loci. RESULTS: Of all 51 patients, 16 (31%) had a family history of OAVS. Most had no relevant pre-natal history and only 5 (10%) cases had a history of environmental exposures that have previously been described as risk factors for OAVS. In 28 (55%) cases, the malformations were unilateral. When the involvement was bilateral, it was asymmetric. Ear abnormalities were present in 47 (92%) patients (unilateral in 24; and bilateral in 23). Hearing loss was common (85%), mostly conductive, but also sensorineural, or a combination of both. Hemifacial microsomia was present in 46 (90%) patients (17 also presented facial nerve palsy). Ocular anomalies were present in 15 (29%) patients. Vertebral anomalies were confirmed in 10 (20%) cases; 50% of those had additional heart, brain and/or other organ abnormalities. Brain abnormalities were present in 5 (10%) patients; developmental delay was more common among these patients. Limb abnormalities were found in 6 (12%) patients, and urogenital anomalies in 5 (10%). Array-CGH analysis identified 22q11 dosage anomalies in 10 out of 22 index cases screened. DISCUSSION: In this study we carried out in-depth phenotyping of OAVS in a large, multicentre cohort. Clinical characteristics are in line with those reported previously, however, we observed a higher incidence of hemifacial microsomia and lower incidence of ocular anomalies. Furthermore our data suggests that OAVS patients with vertebral anomalies or congenital heart defects have a higher frequency of additional brain, limb or other malformations. We had a higher rate of familial cases in our cohort in comparison with previous reports, possibly because these cases were referred preferentially to our genetic clinic where family members underwent examination. We propose that familial OAVS cases show phenotypic variability, hence, affected relatives might have been misclassified in previous reports. Moreover, in view of its phenotypic variability, OAVS is potentially a spectrum of conditions, which overlap with other conditions, such as mandibulofacial dysostosis. Array CGH in our cohort identified recurrent dosage anomalies on 22q11, which may contribute to, or increase the risk of OAVS. We hypothesize that although the 22q11 locus may harbour gene(s) or regulatory elements that play a role in the regulation of craniofacial symmetry and 1st and 2nd branchial arch development, OAVS is a heterogeneous condition and many cases have a multifactorial aetiology or are caused by mutations in as yet unidentified gene(s)
Structure and bonding in Au(I) chloride species: a critical examination of X-ray absorption spectroscopy (XAS) data
No full textAu(I) chloride species are important reactants and intermediates in various processes across the chemical sciences and engineering. Structure and bonding in Au(I) species are often characterized by X-ray absorption spectroscopy (XAS), including measurements under reaction conditions. Previously reported XA spectra for Au(I) chloride species have varied significantly, likely as a result of radiation damage and/or partial disproportionation of [AuCl2]- ions, which are metastable under ambient conditions. By monitoring the decomposition of tetrabutylammonium dichloroaurate(I), TBA[AuCl2], in 1,2-dichlorobenzene we have obtained a reliable X-ray absorption spectrum of [AuCl2]- ions by combining the calculation of difference spectra with an extended X-ray absorption fine-structure (EXAFS) determination of the solution composition. The results show that the X-ray absorption near-edge structure (XANES) of [AuCl2]- is characterized by a weak Au 2p3/2 /5d ("€˜white line"€™) transition, which agrees well with the spectrum predicted by electronic structure calculations using the FEFF8 code. Compared to [AuCl4]-, the determined [AuCl2]- spectrum has several distinctive features of diagnostic analytical value. A more detailed densities of states (DOS) analysis of the electronic structure suggests that the weak white line arises from a hybrid Au 6s/5d DOS band that is partially occupied, up to the level of the highest occupied molecular orbital (HOMO). Correlation of Cl coordination numbers determined from the EXAFS with the intensity of the white line in the XANES indicates that the decomposition is a primarily radiation-induced oxidation to Au(III) species with an average formula of [AuCl3OH]-
