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Isabel A. Cáceres Mariana Arcaya Eugene Declercq Candice M. Belanoff Vanitha Janakiraman Bruce Cohen Jeffrey Ecker Lauren A. Smith S. V. Subramanian 《PloS one》2013,8(3)
Objective
We examined the extent to which differences in hospital-level cesarean delivery rates in Massachusetts were attributable to hospital-level, rather than maternal, characteristics.Methods
Birth certificate and maternal in-patient hospital discharge records for 2004–06 in Massachusetts were linked. The study population was nulliparous, term, singleton, and vertex births (NTSV) (n = 80,371) in 49 hospitals. Covariates included mother''s age, race/ethnicity, education, infant birth weight, gestational age, labor induction (yes/no), hospital shift at time of birth, and preexisting health conditions. We estimated multilevel logistic regression models to assess the likelihood of a cesarean deliveryResults
Overall, among women with NTSV births, 26.5% births were cesarean, with a range of 14% to 38.3% across hospitals. In unadjusted models, the between-hospital variance was 0.103 (SE 0.022); adjusting for demographic, socioeconomic and preexisting medical conditions did not reduce any hospital-level variation 0.108 (SE 0.023).Conclusion
Even after adjusting for both socio-demographic and clinical factors, the chance of a cesarean delivery for NTSV pregnancies varied according to hospital, suggesting the importance of hospital practices and culture in determining a hospital''s cesarean rate. 相似文献54.
Efthalia K. Chatziefstratiou Gil Bohrer Anthony S. Bova Ravishankar Subramanian Renato P. M. Frasson Amy Scherzer Bret W. Butler Matthew B. Dickinson 《PloS one》2013,8(7)
FireStem2D, a software tool for predicting tree stem heating and injury in forest fires, is a physically-based, two-dimensional model of stem thermodynamics that results from heating at the bark surface. It builds on an earlier one-dimensional model (FireStem) and provides improved capabilities for predicting fire-induced mortality and injury before a fire occurs by resolving stem moisture loss, temperatures through the stem, degree of bark charring, and necrotic depth around the stem. We present the results of numerical parameterization and model evaluation experiments for FireStem2D that simulate laboratory stem-heating experiments of 52 tree sections from 25 trees. We also conducted a set of virtual sensitivity analysis experiments to test the effects of unevenness of heating around the stem and with aboveground height using data from two studies: a low-intensity surface fire and a more intense crown fire. The model allows for improved understanding and prediction of the effects of wildland fire on injury and mortality of trees of different species and sizes. 相似文献
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Neha S. Joshi R.B. Subramanian 《Archives Of Phytopathology And Plant Protection》2013,46(15):1773-1789
Roots of the susceptible “JG-62” and resistant “WR-315” chickpeas (Cicer arietinum L.) were inoculated with a conidial suspension of Fusarium oxysporum f. sp. ciceris. Anatomical and biochemical studies were carried out in a time-course manner to elucidate the infection process and plant defence reactions. Scanning electron microscope images revealed fungal colonisation in the root hair region. Early occurrence of fungal biofilms associated with the infected “JG-62” root epidermis was also visualised. After 96 h of inoculation, a gradual accumulation of polysaccharide positive deposits was observed in the xylem vessels of the infected “JG-62” roots. Fungal mycelium was observed in the vessel lumen of infected “JG-62” after 22 days of inoculation. Due to fungal invasion during this period, some of the vessels also appeared collapsed in “JG-62”, whereas vessels in “WR-315” remained intact. The host plant defence responses specifically linked to the susceptible interactions were the induction of ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase in roots and shoots. 相似文献
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In this work, the Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 2-aminobiphenyl (2ABP) were recorded in the solid phase. The optimised geometry, frequency and intensity of the vibrational bands of 2ABP were obtained by the density functional theory (BLYP and B3LYP) methods with complete relaxation in the potential energy surface using 6-31G(d) basis set. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FT-IR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed spectrograms. 相似文献
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R. Vijayalakshmi V. Subramanian Balachandran Unni Nair 《Journal of biomolecular structure & dynamics》2013,31(6):1063-1071
Abstract Molecular modeling and energy minimisation calculations have been used to investigate the interaction of chromium(III) complexes in different ligand environments with various sequences of B-DNA. The complexes are [Cr(salen)(H2O)2]+; salen denotes 1, 2 bis-salicylideneaminoethane, [Cr(salprn)(H2O)2]+; salprn denotes 1, 3 bis- salicylideneamino-propane, [Cr(phen)3]3+; phen denotes 1, 10 phenanthroline and [Cr(en)3]3+; en denotes eth- ylenediamine. All the chromium(III) complexes are interacted with the minor groove and major groove of d(AT)12, d(CGCGAATTCGCG)2 and d(GC)12 sequences of DNA. The binding energy and hydrogen bond parameters of DNA-Cr complex adduct in both the groove have been determined using molecular mechanics approach. The binding energy and formation of hydrogen bonds between chromium(III) complex and DNA has shown that all complexes of chromium(III) prefer minor groove interaction as the favourable binding mode. 相似文献
60.
Thankaraj Salammal Mariashibu Kondeti Subramanyam Muthukrishnan Arun Subramanian Mayavan Manoharan Rajesh Jeevaraj Theboral Markandan Manickavasagam Andy Ganapathi 《Acta Physiologiae Plantarum》2013,35(1):41-54
For the first time we have developed a reliable and efficient vacuum infiltration-assisted Agrobacterium-mediated genetic transformation (VIAAT) protocol for Indian soybean cultivars and recovered fertile transgenic soybean plants through somatic embryogenesis. Immature cotyledons were used as an explant and three Agrobacterium tumefaciens strains (EHA 101, EHA 105, and KYRT 1) harbouring the binary vector pCAMBIA1301 were experimented in the co-cultivation. The immature cotyledons were pre-cultured in liquid somatic embryo induction medium prior to vacuum infiltration with the Agrobacterium suspension and co-cultivated for 3 days on co-cultivation medium containing 50 mg l?1 citric acid, 100 µM acetosyringone, and 100 mg l?1 l-cysteine. The transformed somatic embryos were selected in liquid somatic embryo induction medium containing 10 mg l?1 hygromycin and the embryos were germinated in basal medium containing 20 mg l?1 hygromycin. The presence and integration of the hpt II and gus genes into the soybean genome were confirmed by GUS histochemical assay, polymerase chain reaction, and Southern hybridization. Among the different combinations tested, high transformation efficiency (9.45 %) was achieved when immature cotyledons of cv. Pusa 16 were pre-cultured for 18 h and vacuum infiltrated with Agrobacterium tumefaciens KYRT 1 for 2 min at 750 mm of Hg. Among six Indian soybean cultivars tested, Pusa 16 showed highest transformation efficiency of 9.45 %. The transformation efficiency of this method (VIAAT) was higher than previously reported sonication-assisted Agrobacterium-mediated transformation. These results suggest that an efficient Agrobacterium-mediated transformation protocol for stable integration of foreign genes into soybean has been developed. 相似文献