405 research outputs found
Personal exposures of children to nitrogen dioxide relative to concentrations in outdoor air
No full textObjectives: To investigate the relation between fluctuations in personal exposure to nitrogen dioxide (NO2) in school children and changes in outdoor NO2 concentrations.Methods: 114 Asthmatic school children aged 7-12 years were recruited from the Southampton area. Weekly average personal exposures to NO2 were measured over a 13 month period with passive diffusion tubes. At the same time, outdoor NO2 concentrations were monitored at a fixed site in the centre of Southampton. Correlations between weekly personal exposures and mean outdoor concentrations during the same periods were examined.Results: Mean duration of follow up was 32 weeks. Measurements of weekly mean personal NO2 exposures were generally low and ranged from 0.7 to 496 µg/m3 with a geometric mean of 17 µg/m3. Substantial variation in personal exposures occurred between children and more especially within individual children from week to week. Daily outdoor concentrations of NO2 ranged from 4.3 to 29.8 µg/m3, with a geometric mean of 12.3 µg/m3. There was no evidence of seasonal variation in outdoor concentrations. No significant correlation was found between each child's weekly mean personal exposures to NO2 and mean outdoor concentrations for the corresponding periods.Conclusion: At low outdoor NO2 concentrations, fluctuations in NO2 in outdoor air as measured at a central monitoring station do not contribute importantly to variations in personal exposure when averaged over a week
An additional record of Fejervarya manoharani Garg and Biju from the Western Ghats with a description of its complete mitochondrial genome
No full textKiran, S. Kumar, Anoop, V. S., Sivakumar, K. C., Dinesh, Raghunathan, Mano, J. P., Kaushik, Deuti, Sanil, George (2017): An additional record of Fejervarya manoharani Garg and Biju from the Western Ghats with a description of its complete mitochondrial genome. Zootaxa 4277 (4): 491-502, DOI: https://doi.org/10.11646/zootaxa.4277.4.
Fibroblast growth factor receptor-1 associated myeloproliferative neoplasm and T-lymphoblastic lymphoma
No full textMyeloid and lymphoid hematological malignancies with eosinophilia and abnormalities of fibroblast growth factor receptor-1 (FGFR1) result from the formation of abnormal fusion genes that encode constitutively activated tyrosine kinases. The WHO classification (2008) of hematolymphoid neoplasms recognizes a category of myeloid and lymphoid neoplasms with eosinophilia and abnormalities of FGFR1. Here, we present the case of a 30-year-old-woman who was diagnosed with T-lymphoblastic lymphoma from lymph node biopsy and myeloproliferative neoplasm with eosinophilia from bone marrow studies. She was treated with combination chemotherapy with cyclophosphamide, vincristine, doxorubicin, and dexamethasone (Hyper-CVAD regimen) and is on maintenance chemotherapy for the past 2 months. We present this case to create awareness among physicians about this rare condition associated with dual malignancies
The initiation and evolution of interfirm knowledge transfer in R&D relationships.
No full textKnowledge; Knowledge transfer; R&D;
Modulation of citrate metabolism alters aluminum tolerance in yeast and transgenic canola overexpressing a mitochondrial citrate synthase
No full textAluminum (Al) toxicity is a major constraint for crop production in acid soils, although crop cultivars vary in their tolerance to Al. We have investigated the potential role of citrate in mediating Al tolerance in Al-sensitive yeast (Saccharomyces cerevisiae; MMYO11) and canola (Brassica napus ev Westar). Yeast disruption mutants defective in genes encoding tricarboxylic acid cycle enzymes, both upstream (citrate synthase [CS]) and downstream (aconitase [ACO] and isocitrate dehydrogenase [IDH]) of citrate, showed altered levels of Al tolerance. A triple mutant of CS (Deltacit123) showed lower levels of citrate accumulation and reduced Al tolerance, whereas Deltaaco1- and Deltaidh12-deficient mutants showed higher accumulation of citrate and increased levels of Al tolerance. Overexpression of a mitochondrial CS (CIT1) in MMYO11 resulted in a 2- to 3-fold increase in citrate levels, and the transformants showed enhanced Al tolerance. A gene for Arabidopsis mitochondrial CS was overexpressed in canola using an Agrobacterium tumefaciens-mediated system. Increased levels of CS gene expression and enhanced CS activity were observed in transgenic lines compared with the wild type. Root growth experiments revealed that transgenic lines have enhanced levels of Al tolerance. The transgenic lines showed enhanced levels of cellular shoot citrate and a 2-fold increase in citrate exudation when exposed to 150 muM Al. Our work with yeast and transgenic canola clearly suggest that modulation of different enzymes involved in citrate synthesis and turnover (malate dehydrogenase, CS, ACO, and IDH) could be considered as potential targets of gene manipulation to understand the role of citrate metabolism in mediating Al tolerance
Design and Analysis of V-Band Electroless Plated Trough Waveguide Antenna
No full textDesign feasibility and antenna element choices make linear antenna arrays a preferred choice for applications at frequencies above 1 GHz. However, restricted bandwidth and limited scanning capabilities reduce the usefulness of these arrays in certain applications. Travelling wave antennas can overcome these problems by varying the phase velocity inside the transmission line to provide a high bandwidth scanning capability. The main beam of such a travelling wave antenna is able scan from the nearendfire to the broadside region. However, the change in the angle of the main beam from endfire to broadside introduces a high impedance mismatch which causes attenuation and reflection losses in the antenna. This research explores impedance matching techniques which could enhance the performance of beam scanning systems by solving this problem. This work covers the design, fabrication, and testing of a V-band Trough waveguide antenna (TWA) which uses tuning elements inside the guide for each perturbation. Additionally, this research covers the design and fabrication of two types of waveguide transitions. One transition connects standard rectangular waveguide to a troughguide, and another transition converts circular waveguide to a troughguide. These transitions achieve the correct orientation of modes at the input of the trough waveguide for a proper operation of the antenna. The initial TWA design uses a rectangular base which is developed into a curved base for each channel in the final design. The curved base improves the fluid flow utilized in the fabrication process of TWA. The initial design used rectangular matching posts attain matching and reduce the reflections at the interface of each perturbation. The final designs used circular/hemispherical matching elements with dimensions based on the rectangular posts allowed smooth edges. The author analyzed tuning elements of various shapes to obtain impedance matching while ensuring the dimensions are viable on the 3D printer available. The next phase of the study investigated maximizing the efficiency and radiation characteristics of the antenna by maximizing the radiated power. Finally, the author attempts reduction in sidelobes of the antenna using amplitude tapering functions such as squared cosine and triangular window for the trough waveguide antenna. The resulting antenna achieves a narrow broadside beam which can be scanned for the entire V-band frequency
Association of Fish Oil and Physical Activity on Mobility Disability in Older Adults
No full textPurpose: This study aimed to examine whether long-term fish oil (FO) supplementation is associated with a lower risk of mobility disability and enhances benefits of physical activity (PA). Methods: A total of 1635 sedentary adults age 70 to 89 yr from the Lifestyle Interventions and Independence for Elders single-blinded randomized,multicenter clinical trial, which compared a structured PA program to a health education program. Primary outcome was incident major mobility disability (MMD), defined by loss of ability to walk 400 m, measured every 6 months for an average of 2.6 yr. Secondary outcomes included persistent mobility disability, Short Physical Performance Battery, 400-m walk speed, and grip strength. Results: A third of participants reported using FO at baseline (456 (28%); mean age, 78.5 yr; 70.5% women). MMD was experienced by 131 participants (28.7%) in the FO group and 405 (34.4%) participants in the nonuser group. After adjusting for confounders, FO supplementation was associated with a lower risk (HR, 0.78; 95%confidence interval (CI), 0.64–0.96) of incident MMD. However, there was no interaction (P = 0.19) between FO supplementation and PA intervention for MMD. For the secondary outcome of persistent mobility disability, the intervention association differed by supplementation (P = 0.002) with PA intervention associations of (HR, 1.36; 95% CI, 0.83–2.23) for users and (HR, 0.61; 95% CI, 0.46–0.81) for nonusers. Changes in physical performance outcomes were not modified by baseline FO supplementation or combination with PA. Conclusions: FO supplementation was associated with a lower risk of MMD in low to moderate functioning older adults. However, supplementation did not enhance the benefit of PA on risk of mobility disability. These results are hypothesis generating and need to be confirmed in randomized trial
Radio Evolution of a Type IIb Supernova SN 2016gkg
No full textAbstract
We present extensive radio monitoring of a Type IIb supernova (SN IIb), SN 2016gkg during t ∼ 8−1429 days postexplosion at frequencies ν ∼ 0.33−25 GHz. The detailed radio light curves and spectra are broadly consistent with self-absorbed synchrotron emission due to the interaction of the SN shock with the circumstellar medium. The model underpredicts the flux densities at t ∼ 299 days postexplosion by a factor of 2, possibly indicating a density enhancement in the circumstellar medium due to a nonuniform mass loss from the progenitor. Assuming a wind velocity v
w ∼ 200 km s−1, we estimate the mass-loss rate to be
M
̇
∼
(2.2, 3.6, 3.8, 12.6, 3.7, and 5.0) ×10−6
M
⊙ yr−1 during ∼8, 15, 25, 48, 87, and 115 yr, respectively, before the explosion. The shock wave from SN 2016gkg is expanding from R ∼ 0.5 × 1016 to 7 × 1016 cm during t ∼ 24−492 days postexplosion indicating a shock deceleration index, m ∼ 0.8 (R ∝ t
m
), and mean shock velocity v ∼ 0.1c. The radio data are inconsistent with a free–free absorption model and higher shock velocities are in support of a relatively compact progenitor for SN 2016gkg.</jats:p
Identification and characterization of C<sub>N67A</sub>+M<sub>F37L</sub> revertant.
No full text(A) Micrographs showing fluorescent clusters of Vero E6 cells infected with ZIKVvenus-CN67A at passage 0 (P0) and passage 5 (P5). (B) Sanger sequencing results analyzed using FinchTV software showing the region of mutation in M protein in the P5 revertant virus. A single nucleotide T→C mutation (highlighted in blue) created an F→L amino acid mutation in the M protein resulting in a ZIKVvenus-CN67A++MF37L double mutant. (C) Virus titers of ZIKVvenus-CN67A mutant and ZIKVvenus-CN67A++MF37L revertant compared to wild-type ZIKVvenus as determined by plaque assay on Vero E6 cells. The graph represents average titers (n = 3) with error bars representing SEM. Statistical significance was calculated by Ordinary one-way ANOVA using GraphPad PRISM 7 software at a 95% confidence interval. Relative significance is indicated by asterisks (pWT and ZIKVWT-CN67A++MF37L. The graph represents average titers (n = 3) at 24-, 48-, 72-, and 96 h.p.i with error bars representing SEM. (E) Western blot of virus pellets obtained after ultracentrifugation of the cell culture supernatants probed with anti-ZIKV C antibody. Label -C on the right indicates a band corresponding to the released ZIKV C protein.</p
Dielectrophoresis: A Review of Applications for Stem Cell Research
No full textDielectrophoresis can discriminate distinct cellular identities in heterogeneous populations, and monitor cell state changes associated with activation and clonal expansion, apoptosis, and necrosis, without the need for biochemical labels. Demonstrated capabilities include the enrichment of haematopoetic stem cells from bone marrow and peripheral blood, and adult stem cells from adipose tissue. Recent research suggests that this technique can predict the ultimate fate of neural stem cells after differentiation before the appearance of specific cell-surface proteins. This review summarises the properties of cells that contribute to their dielectrophoretic behaviour, and their relevance to stem cell research and translational applications.</p
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