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Shunt-related adverse events are frequent in infants after modified Blalock–Taussig despite use of acetylsalicylic acid prophylaxis. A higher incidence of acetylsalicylic acid-resistance and sub-therapeutic acetylsalicylic acid levels has been reported in infants. We evaluated whether using high-dose acetylsalicylic acid can decrease shunt-related adverse events in infants after modified Blalock–Taussig.
In this single-centre retrospective cohort study, we included infants ⩽1-year-old who underwent modified Blalock–Taussig placement and received acetylsalicylic acid in the ICU. We defined acetylsalicylic acid treatment groups as standard dose (⩽7 mg/kg/day) and high dose (⩾8 mg/kg/day) based on the initiating dose.
There were 34 infants in each group. Both groups were similar in age, gender, cardiac defect type, ICU length of stay, and time interval to second stage or definitive repair. Shunt interventions (18 versus 32%, p=0.16), shunt thrombosis (14 versus 17%, p=0.74), and mortality (9 versus 12%, p=0.65) were not significantly different between groups. On multiple logistic regression analysis, single-ventricle morphology (odds ratio 5.2, 95% confidence interval of 1.2–23, p=0.03) and post-operative red blood cells transfusion ⩾24 hours [odds ratio 15, confidence interval of (3–71), p<0.01] were associated with shunt-related adverse events. High-dose acetylsalicylic acid treatment [odds ratio 2.6, confidence interval of (0.7–10), p=0.16] was not associated with decrease in these events.
High-dose acetylsalicylic acid may not be sufficient in reducing shunt-related adverse events in infants after modified Blalock–Taussig. Post-operative red blood cells transfusion may be a modifiable risk factor for these events. A randomised trial is needed to determine appropriate acetylsalicylic acid dosing in infants with modified Blalock–Taussig.
We present here the observations of solar jets observed on April 04, 2017 from NOAA active region (AR) 12644 using high temporal and spatial resolution AIA instrument. We have observed around twelve recurring jets during the whole day. Magnetic flux emergence and cancellation have been observed at the jet location. The multi-band observations evidenced that these jets were triggered due to the magnetic reconnection at low coronal null–point.
An investigation for search of correlation between the daily observations of mean magnetic field and daily flare count number in different class is studied here. The daily observations for mean magnetic field presented here are taken by Wilcox Solar observatory and daily flare count in different X-ray class is provided by National Centers For Environmental Information.
Crab Pulsar (PSR B0531+21) is known to emit pulsed emission in all bands of the electromagnetic spectrum. It also emits giant radio pulses (GRPs) frequently, which are roughly a hundred to million times brighter than the normal pulses. We aim to study whether there is a significant X-ray enhancement correlated with the occurrence of GRPs, using simultaneous observations with the ASTROSAT, the Giant Meterwave Radio telescope (1300 MHz) and the Ooty Radio telescope (325 MHz). This required determination of fixed pipeline offsets between different instruments. We find the offset between ASTROSAT and GMRT to be −30.181 ± 0.095 ms and that between ASTROSAT and ORT to be −18.4 ± 0.2 ms. Our preliminary results with 1300 MHz data also show a break in pulse intensity distribution at ~ 33 Jy in the main pulse and ~ 28 Jy in the inter-pulse.
Plant breeding makes genetic gains over years, so growing newer varieties generally provides greater benefits than growing older ones. However, in low-altitude districts of Nepal, a few rice varieties covered 75% of the rice area and were more than 20 years old (first paper in this series). We test here if this slow rate of adoption of new varieties could be accelerated using a participatory method, Informal Research and Development (IRD), where packets of seeds of new rice varieties are widely distributed to many farmers. From 2008 to 2011, over 117 000 IRD packets were distributed in 18 districts of the Nepal Terai, including over 70 000 of three released varieties from a client-oriented breeding (COB) programme in Nepal. The IRD significantly increased the adoption of the three COB varieties. The benefits obtained by farmers in a single growing season equal the costs of IRD, if for every 75 kits distributed an additional 1 ha is grown. This assumes that the new varieties produce a 10% increase in yield (lower than that evidenced in their release proposals). On an average, fewer than three IRD kits were distributed for each hectare of a new variety grown by farmers in 2011. Furthermore, the effectiveness of IRD could be increased 1.2 to 2.7 fold (depending on the COB variety) if the IRD distribution were to be restricted to the region where the variety was most accepted. The best comparison of IRD with extension by the conventional system was their popularity compared with similar-aged varieties that had been promoted in the two systems. The adoption of three COB varieties was about twicethat of three varieties from the National Rice Research Programme (NRRP) that were closest in release date to the COB varieties. Unlike cost effectiveness assessed by hectares grown per IRD kit distributed, this comparison can only indicate efficacy because, as well as extension method, many factors influenced the adoption rates of the COB and NRRP varieties. The costs of IRD are small, both relative to the cost of breeding new varieties and to the benefits gained; so it is one of the simplest and most cost-effective interventions to increase agricultural productivity.
Farmers who continue to grow old and obsolete varieties do not gain the benefits they could get from growing newer ones. Given the potential large scale of these foregone benefits, relatively few studies have examined the age of varieties that farmers grow. In three surveys, members of over 3300 households were interviewed to find the rice varieties they grew in 2008 and 2011 in 18 districts in the Terai, the low-altitude region of Nepal. This provided the first description of detailed geographical patterns of adoption of rice varieties and their ages that were repeated over time. There were large differences between district and individual varieties that showed specific geographical patterns of adoption. Such detailed knowledge on spatial diversity of varieties is invaluable for planning extension activities and developing breeding programmes, and cheaper ways than household surveys of collecting this information are discussed. Some of the factors considered important in determining this complex pattern of adoption were seed availability, growing environments that differed from east to west and the continued popularity of varieties once they had established markets. Rice diversity was low because a small number of rice varieties occupied large areas. In 2011, nine varieties covered at least 75% of the total rice area in western districts, just four in central districts and eight in eastern districts. Of these, most were released before 1995 resulting in a high average age of the predominant varieties – they always had an average age of over 20 years no matter which region or year was considered. Even though there were some large changes in varietal composition from 2008 to 2011, the average age of the predominant varieties remained almost the same. In a second paper in this series, we examine how these very low varietal replacement rates, that reduce yields and increase risk to farmers, can be accelerated using a participatory research for development approach called Informal Research and Development (IRD) (Joshi et al., 2012).
Pulsation is ubiquitous among chemically normal A-type stars, but comparatively rare among chemically peculiar Am and Ap stars of the same temperature range. The conventional explanation for this is that diffusion produces the surface abundance anomalies in the Am and Ap stars, and also drains He from the He-II ionisation zone, thus quenching the κ-mechanism that drives δ Scuti pulsation. The pulsating Am and Ap stars exhibit dichotomous pulsation characteristics. The Am stars (and related stars) exhibit low-overtone δ Scuti pulsation, with amplitudes ranging from a few mmag to 0.1 mag. The pulsating Ap stars exhibit high-overtone pulsation with periods in the range 6-16 min and Johnson B semi-amplitudes typically ≤ 5 mmag. These stars are referred to as rapidly oscillating Ap stars, or ‘roAp’ stars (the see review by Martinez & Kurtz 1995).
A regional, multistate investigation into a June–August 2013 cyclosporiasis outbreak was conducted in Nebraska, Iowa, and neighbouring states. Cases were confirmed on the basis of laboratory and clinical findings. Of 227 cases in Iowa (n = 140) and Nebraska (n = 87) residents, 162 (71%) reported dining at chain A/B restaurants – 96% reported house salad consumption. A case-control study identified chain A/B house salad as the most likely vehicle. Traceback was conducted to ascertain production lot codes of bagged salad mix (iceberg and romaine lettuce, red cabbage, and carrots) served as house salad in implicated restaurants. A single production lot code of salad mix supplied by both a common producer and distributor was linked to the majority of confirmed cases in persons reporting regional chain A/B exposure. The salad mix linked to illnesses contained imported romaine lettuce from two separate single-grower fields-of-origin and ⩾1 additional field from another grower.
The thyroid gland is removed en bloc during laryngectomy. There are no objective criteria for deciding the extent of thyroid gland resection in primary hypopharyngeal cancer cases. The present study aimed to determine the incidence of thyroid gland involvement in hypopharyngeal cancer and identify the various predictors of this involvement.
This paper reports a retrospective analysis of 358 patients with hypopharyngeal cancer, who underwent total laryngectomy with partial or total pharyngectomy at Tata Memorial Hospital, Mumbai between 2004 and 2010.
The mean age of this population was 61 years. The pyriform sinus was the most common hypopharyngeal subsite involved (in 89 per cent of cases). Most patients underwent hemi-thyroidectomy as part of their surgery. The thyroid gland was involved in only 13 per cent of cases.
Thyroid gland involvement is not common in hypopharyngeal cancer. Cases that involved the post-cricoid area, subglottic extension, extralaryngeal spread or prior tracheostomy were associated with a higher risk of thyroid gland involvement. Ipsilateral thyroidectomy is sufficient in most patients undergoing surgery (laryngectomy with partial or total pharyngectomy) for hypopharyngeal cancers.
We report observations of a long filament that underwent recurrent partial eruptions on August 4, 6, and 8, 2012. The filament reappeared in the subsequent rotation of the Sun, and disappeared completely on August 31, 2012. We implemented an automated filament detection algorithm developed by us for estimating different attributes of these filaments few hours prior to its disappearance in Hα and studied their evolution. Based on these attributes, we determine the onset time of the disappearance of Hα filaments. We then compared these onset times with that of the associated CMEs observed by LASCO/SOHO coronagraphs. This is also useful to understand temporal relationship of EUV and X-ray flux variation associated with filament disappearances in Hα. Our results show the importance of such studies in understanding the mechanism of CME initiation, particularly the role of eruptive filaments, in this process.
Insufficiency of vitamin B12 (B12) and folate during pregnancy can result in low concentrations in the fetus and have adverse effects on brain development. We investigated the relationship between maternal B12 and folate nutrition during pregnancy and offspring motor, mental and social development at two years of age (2 y). Mothers (n = 123) and their offspring (62 girls, 61 boys) from rural and middle-class urban communities in and around Pune city were followed through pregnancy up to 2 y. Maternal B12 and folate concentrations were measured at 28 and 34 weeks of gestation. At 2 y, the Developmental Assessment Scale for Indian Infants was used to determine motor and mental developmental quotients and the Vineland Social Maturity Scale for the social developmental quotient. Overall, 62% of the mothers had low B12 levels (<150 pmol/l) and one mother was folate deficient during pregnancy. Maternal B12 at 28 and 34 weeks of gestation was associated with offspring B12 at 2 y (r = 0.29, r = 0.32, P < 0.001), but folate was not associated with offspring folate. At 2 y, motor development was associated with maternal folate at 28 and 34 weeks of gestation. Mental and social development quotients were associated positively with head circumference and negatively with birth weight. In addition, pregnancy B12 and folate were positively associated with mental and social development quotients. Maternal B12 and folate during intrauterine life may favorably influence brain development and function. Pregnancy provides a window of opportunity to enhance fetal psychomotor (motor and mental) development.
Pulsed laser direct deposit Ni2Si Ohmic contacts were successfully fabricated on n-SiC. The electrical, structural, compositional, and surface morphological properties were investigated as a function of heat treatments ranging from 700 °C to 950 °C. The as-deposited and 700 °C annealed samples were non-Ohmic. Annealing at 950 C° yielded excellent Ohmic behavior, an abrupt void free interface, and a smooth surface morphology. No residual carbon was present within the contact film or at the film-SiC interface and the contact showed no appreciable contact expansion as a result of the 950 °C annealing process. Results of this investigation demonstrate that 950 °C annealed pulse laser deposited Ni2Si-SiC contacts possess excellent electrical, interfacial, microstructural, and surface properties, which are required for reliable device operation.
Molecular materials comprised of inorganic:organic composites are of considerable interest in photonics, optoelectronics and biophotonics. We report broad band lasing and tunable filters in sol-gel processed poly (p-phenylene vinylene) PPV: Silica composites. Optical power limiting in near IR wavelength region is also reported in dye doped PPV: silica multiphasic nanocomposites. For making hybrid inorganic: organic composites the reverse micelle mediated synthesis technique has been exploited to synthesize dye encapsulated metal oxide particles, thiocresol capped CdS clusters, Cul and AgI nanoparticles. These particles were dispersed in polymeric matrix for applications in photoconductivity and photorefractive measurements.
Non-equilibrium electron distributions as well as phonon dynamics in wurtzite GaN have been measured by subpicosecond time-resolved Raman spectroscopy. Our experimental results have demonstrated that for electron densities n ≥ 5 × l017cm−3, the non-equilibrium electron distributions in wurtzite GaN can be very well described by Fermi-Dirac distribution functions with the temperature of electrons substantially higher than that of the lattice. The population relaxation time of longitudinal optical phonons was directly measured to be τ ≅ 5 ± 1 ps at T = 25 K. The experimental results on the temperature dependence of the lifetime of longitudinal optical phonons suggest that the primary decay channels for these phonons are the decay into (1) one transverse optical phonon and one high energy, longitudinal or transverse acoustical phonons; and (2) one transverse optical phonon and one E2 phonon.
This research investigates the potential of pulsed laser deposition to create reliable high current ohmic contacts of Ni2Si on single crystal 4H-SiC. Since this stoichiometry is the stable interphase in the nickel-silicon carbide diffusion couple, direct deposition eliminates the detrimental excess carbon normally formed by direct sintering Ni on SiC, the surface roughening that results from this sintering as well as the need for post-deposition high-temperature (900°C) anneals that are required in complex multi-component contacts. This study examines the processing parameters that must be used during deposition to obtain the desired microstructural characteristics for the contact. Pulsed laser deposition of nickel silicide produces smooth films with an amorphous or nanocrystalline structure interspersed with macroparticles. Macroparticle formation on the resulting films appear in the form of solidified droplets of the eutectic composition nickel silicide (3:1) that form during the long term target processing. The dependence of the number and size distributions of these droplets on laser fluence sample temperature is examined.
Sulfur nanoparticles were synthesized from hazardous H2S gas by desulfurization based on liquid redox process . The use of novel biodegradable iron chelates, in particular, FeCl3-malic acid chelate system has been extensively studied in various aqueous surfactant systems of Tween 80, SDS, CTAB for catalytic oxidation of H2S gas at ambient conditions of temperature, pressure and neutral pH. The structural features of sulfur nanoparticles have been characterized by XRD, TEM, and DLS measurements. XRD analysis indicates the presence of Metal-sulfur (JCPDS-08247). TEM analysis shows that the morphology of sulfur nanoparticles synthesized in aqueous surfactant system of Tween 80 is nearly uniform in size of 12nm average particle size, in SDS surfactant system shows 15nm average particle size, where as sulfur nanoparticles synthesized in CTAB shows average particle size of 7nm. The DLS result shows the mono-dispersity of the sulfur nanoparticles in the aqueous surfactant systems. The described process serves mainly two objectives; (a) waste utilization for preparation of commercially important nano-sulfur product and (b) reduction in environmental pollution. 1. G. Nagal, Chem. Eng. 104, 125 (1997).
Compositionally asymmetric tri-color superlattices (TCS) with a combination of BaTiO3/SrTiO3/CaTiO3 have been grown by pulsed laser deposition (PLD) on atomically-flat SrRuO3-covered (001) SrTiO3 substrates. Conducting SrRuO3 films with single-terrace steps that closely mimic those of the SrTiO3 substrate also were grown by PLD and serve as bottom electrodes. In order to achieve atomic control of each layer, we have calibrated precisely the number of laser pulses required to grow one unit-cell-thick layers (∼200 for a laser spot of 0.4 mm2). These conditions allowed recording of pronounced oscillations of the reflection high-energy electron diffraction (RHEED) specular spot intensity over the entire growth run - even for TCS layers totaling more than 1000 nm in total thickness.