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Methane (CH4) consumption in agricultural soil is imperative for the mitigation of climate change. However, the effect of tillage and cropping systems on CH4 consumption is less studied. Experiments were carried out in Madhya Pradesh, India with soybean-wheat (SW), maize-wheat (MW) and maize-gram (MG) cropping systems under conventional tillage (CT) and no-tillage (NT). Soybean/maize was cultivated during the kharif season (July–October) and wheat/chickpea in the rabi season (October–March) for 9 years consecutively. Soil samples were collected during vegetative growth stages of soybean and maize from different cropping systems. Methane consumption, the abundance of methanotrophs as particulate methane monooxygenase (pmoA) gene copies, soil and crop parameters were estimated. Methane consumption rate was higher in NT and upper soil layer (0–5 cm) than CT and 5–15 cm depth. Methane consumption rate k ranged from 0.35 to 0.56 μg CH4 consumed/g soil/d in the order of MW>SW>MG in 0–5 cm. The abundance of pmoA gene copies ranged from 43 × 104/g soil to 13 × 104/g soil and was highest in MW-NT and lowest in MG-CT. Available nitrogen, phosphorus and potassium were higher in 0–5 cm than in 5–15 cm depth. Soil and plant parameters and abundance of pmoA genes correlated significantly and positively with CH4 consumption rate. No-tillage stimulated CH4 consumption compared to CT irrespective of cropping system and CH4 consumption potential was highest in MW and lowest in MG. However, the magnitude of the positive effect of NT towards CH4 consumption was higher in SW and MG than MW.
The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
We have carried out an ALMA Cycle 2 survey of 15 confirmed or candidate low-mass (<0.2M⊙) members of the TW Hya Association (TWA) with the goal of detecting line emission from CO molecular gas and continuum emission from cold dust. Our targets have spectral types of M4-L0 and hence represent the extreme low end of the TWA's mass function. The survey has yielded a detection of 12CO(2–1) emission around TWA 34. This newly discovered ~10 Myr-old molecular gas disk lies just ~50pc from Earth.
Low-temperature stress is an important factor affecting the growth and development of rice in temperate and high-elevation areas. In this study, 220 germplasm lines were used for screening of tolerant genotypes, validation of molecular markers and identification of robust markers for seedling-stage chilling stress tolerance to be used in marker-assisted breeding (MAS) programme. The temperature regimes imposed in the growth chamber simulated cold-stress injuries at the seedling stages of the germplasm lines. The genotypes were classified into six classes: those having susceptible genotypes were classified into moderately and highly susceptible types, while tolerant types into moderately tolerant, tolerant, highly tolerant and very highly tolerant classes. Genotypes namely Langma, Umleng-1 and Geetanjali showed survival up to 25 d, which were better than the positive check Kalinga-III surviving up to 20 d under chilling stress. Ten simple sequence repeat (SSR) markers were tested for differentiation of genotypes. Individual use of SSR markers like RM284, RM286, RM85, RM341 and RM5746 can be applied in MAS breeding including combination use of non-pair markers like RM284, RM239 and RM85, which was even better than the combined use of RM284 and RM85. However, combined use of all ten markers can most effectively be employed for cold tolerance through MAS breeding.
Aspiration pneumonia is an important cause of death in head and neck cancer patients. This study therefore aimed to evaluate the risk factors associated with aspiration pneumonia in head and neck cancer patients.
Hospital death records from 12 years (2000–2012) were reviewed to obtain the number of deaths. Treatment details and cause of death were analysed. Statistical analysis was performed to identify the risk factors for aspiration pneumonia.
The records revealed that aspiration pneumonia was the cause of death in 51 out of 85 patients. Primary tumour site (oropharynx and hypopharynx, odds ratio 3.3; 95 per cent confidence interval 1.17–9.4, p = 0.02) and advanced tumour stage (odds ratio 4.2, 95 per cent confidence interval 1.16–15.61, p = 0.02) had significant negative impacts on aspiration pneumonia related mortality.
Advanced pharyngeal cancer patients are at an increased risk of aspiration pneumonia related death. Investigations for the early detection of this condition are recommended in these high-risk patients.
Insulin-like growth factor binding protein-5 (IGFBP-5) is a key molecule in
mammary gland development, which facilitates the removal of mammary epithelial
cells (MECs) by apoptosis that takes place during remodeling of the mammary
gland during involution. IGFBP-5 binds with IGFs for their bioavailability.
IGFBP-5 has been reported to perform pleiotropic roles such as cellular
apoptosis, proliferation and differentiation. To understand the role of IGFBP-5
during lactation and clinical mastitis, expression profiling of IGFBP-5 at the
protein level was performed in both indigenous cows (Bos
indicus) and buffaloes (Bubalus bubalis) belonging to
two different breeds – Sahiwal cows and Murrah buffaloes.
Reverse-transcriptase PCR (RT-PCR) of IGFBP-5 mRNA confirmed its expression in
milk somatic cells and MECs of Sahiwal cows. ELISA was performed for
quantitative measurement of IGFBP-5 concentrations in milk during different days
(0, 50, 100, 150, 200, 250 and 300) of lactation, during the involution period
and in animals exhibiting short lactation and clinical mastitis. The highest
concentration of IGFBP-5 in milk was observed during the involution period
followed by colostrum, late and early lactation, respectively, in both cattle
and buffaloes. No significant difference in the concentration of IGFBP-5 was
observed during the first 150 days of lactation between cows and buffaloes.
However, higher concentration of IGFBP-5 was observed in cows during late
lactation (200 to 300 days) in comparison with buffaloes. To validate the ELISA
data, quantitative real-time PCR was performed in MECs of Sahiwal cows. The
relative mRNA abundance of IGFBP-5 was found to be significantly
(P<0.05) higher on day 15 than between 50 and 150
days of lactation in case of Sahiwal cows. Highest mRNA expression of IGFBP-5
was observed around 300 days of lactation followed by 200 and 250 days
(P<0.05), respectively. Murrah buffaloes showed
low levels of IGFBP-5 protein in milk as compared with Sahiwal cows during
lactation in ELISA. Animals having history of short lactation length (short
lactating animals) showed higher levels of IGFBP-5 expression (at protein level)
in comparison with normal lactating animals. We propose that higher level
IGFBP-5 expression may have functional significance in lactation persistency. As
a pro-apoptotic molecule, higher expression of IGFBP-5 was observed to be
inversely related to lactation length and milk production.
To explore the treatment outcomes of patients treated with re-irradiation for recurrent or second primary head and neck cancer.
An analysis was performed of 79 head and neck cancer patients who underwent re-irradiation for second primaries or recurrent disease from January 1999 to December 2011.
Median time from previous radiation to re-irradiation for second primary or recurrence was 53.6 months (range, 2.7–454.7 months). Median age at diagnosis of first primary was 54 years. Median re-irradiation dose was 45 Gy (range, 45–60 Gy). Acute grade 3 or worse toxicity was seen in 30 per cent of patients. Median progression-free survival for recurrent disease was 15.0 months (95 per cent confidence interval, 8.33–21.66). The following factors had a statistically significant, positive impact on progression-free survival: patient age of less than 50 years (median progression-free survival was 29.43, vs 13.9 months for those aged 50 years or older; p = 0.004) and disease-free interval of 2 years or more (median progression-free survival was 51.66, vs 13.9 months for those with less than 2 years disease-free interval).
Re-irradiation of second primaries or recurrences of head and neck cancers with moderate radiation doses yields acceptable progression-free survival and morbidity rates.
This paper examines the trends in utilization of five indicators of reproductive and child health services, namely, childhood immunization, medical assistance at delivery, antenatal care, contraceptive use and unmet need for contraception, by wealth index of the household in India and two disparate states, Uttar Pradesh and Maharashtra. The data from three rounds of the National Family and Health Survey conducted during 1992–2005 are analysed. The wealth index is computed using principal component derived weights from a set of consumer durables, land size, housing quality and water and sanitation facilities of the household, and classified into quintiles for all three rounds. Bivariate analyses, rich–poor ratio and concentration index are used to understand the trends in utilization of, and inequality in, reproductive and child health services. The results indicate huge disparities in utilization of these services, largely to the disadvantage of the poor. Utilization of basic childhood immunization among the poorest and the poor stagnated in India, as well as in both states, during 1998–2005 compared with 1992–1998. The use of maternal care services such as medical assistance at delivery and antenatal care remained at a low level among the poor over this period. However, contraceptive use increased relatively faster among the poor, even with higher unmet need. Of all these services, the inequality in medical assistance at delivery is consistently large, while that of contraceptive use is small. The state-level differences in service coverage by wealth quintiles over time are large.
To improve case selection for near-total laryngectomy by identifying the causes of poor oncological and functional outcomes.
Analysis of prospectively accrued data for 28 consecutive cases of near-total laryngectomy undertaken between 1996 and 2005 at a tertiary care centre. We analysed the impact of tumour extent and location, patient physiological status, and surgical technique on disease-free survival and on functional outcome.
Patients' average four-year Kaplan–Meier disease-free survival was 74 per cent (95 per cent confidence intervals, 46–89 per cent). Eighty-two per cent of patients had good to excellent functional outcomes. Pre-operative tumour extension to the ipsilateral arytenoid significantly compromised disease-free survival (patients with this development had a two-year survival of 40 per cent; p = 0.001). Internal communicating fistula formation (i.e. a fistula between the neopharynx and myomucosal shunt lumens) occurred in five of 28 cases and was uniformly associated with a poor functional outcome (i.e. lack of phonation with or without aspiration). Fistula formation was significantly more likely in cases with tumour involving the ipsilateral arytenoid and the ipsilateral subglottis.
Significant disparity exists for the functional outcome of near-total laryngectomy in patients who develop post-surgical internal fistula, compared with those with uneventful healing. Tumour involvement of the ipsilateral arytenoid compromises the oncological and functional results. Tumour extension to the subglottis may compromise functional outcome. Near-total laryngectomy should be avoided in cases with ipsilateral arytenoid involvement, and undertaken with caution in cases with subglottic extension.
Head and neck cancer care was analysed in 2167 unselected patients for management compliance and outcome. Median age was 55 years, with a male to female ratio of 5.5[ratio ]1. Major sites were oropharynx (32.4 per cent), larynx (19.8 per cent), oral (16.6 per cent) and hypopharynx (12.9 per cent). Stage-wise distribution was I–II=8.9 per cent, III=20.6 per cent and IV=60.3 per cent and unstaged=10.2 per cent. Squamous cell carcinoma was the dominant histology for 90.9 per cent. Clinic-based cancer-directed treatment decisions were made for 1905 patients: curative intent in 53 per cent, palliative in 35 per cent and for the remaining 262 (12 per cent) supportive care. Overall, 1209 (56 per cent) patients complied with the prescribed treatments; 62 per cent, 54 per cent, and 35 per cent of curative, palliative and supportive care intent groups, respectively. Modalities were radiotherapy alone (64.6 per cent), combined surgery with irradiation (17.6 per cent), and chemoradiotherapy (11.2 per cent). Median follow-up periods were 17.5 and three months in curative and palliative groups respectively. Overall, 712 (33 per cent) cases received curative therapy, with three-year disease-specific survival of 49 per cent. Patient compliance was a major obstacle. The comparison of this series with the USA, Canada and Norway showed wide disparities in stage of presentation and survival.
The antibiogram pattern and seasonal distribution of Salmonella serotypes were analysed retrospectively over a 6-year period from January 1999 to December 2004. Blood cultures received in the Bacteriology Laboratory were processed by standard procedures and the Salmonella spp. isolates were identified with specific antisera and standard biochemical tests. Antimicrobial susceptibility testing was carried out by a standard disc diffusion method and the minimum inhibitory concentration (MIC) of ciprofloxacin for 332 representative Salmonella isolates was determined by E test. Salmonella Typhi (75·7%) was the predominant serotype among 830 Salmonella spp. isolated during the study period followed by S. Paratyphi A (23·8%). The maximum number of enteric fever cases occurred during April–June (dry season) followed by July–September (monsoon season). There was a decrease in multidrug-resistant (MDR) S. Typhi, but MDR S. Paratyphi A isolates increased. There was also a dramatic increase in nalidixic acid-resistant isolates. All isolates were susceptible to third-generation cephalosporins and ciprofloxacin except one S. Typhi strain which demonstrated high-level ciprofloxacin resistance with a MIC of 16 μg/ml. A knowledge of the seasonal distribution and antibiotic resistance pattern of Salmonella in a particular geographical region is helpful in the delineation of appropriate control measures required for prevention of enteric fever.
Nacre, the shiny inner layer of seashells is a model biomimetic system composed of 95% of inorganic (aragonite) phase and 5% of organic phase (mainly proteins and polysaccharides). Nacre exhibits an interlocked layered “brick and mortar” structure where the bricks are made up of aragonite and mortar is the organic phase. We have performed nanoindentation and dynamic nanoindentation tests to study the nanomechanical and dynamic nanomechanical response of nacre. The indentation experiments performed at low loads indicate an elastic modulus of about 15 GPa for the organic phase. The low load, low penetration experiments appear to be better indicators of nanomechanical behavior. Dynamic nanomechanical response of nacre was studied using dynamic nanoindentation (nano-DMA). Significant increase in the values of tan δ was observed with increase in frequency. Also the dynamic nanoindentation experiments indicate that nacre exhibits viscoelastic behavior. Further, fourier transform spectroscopy experiments of nacre in innate and undisturbed state indicate the presence of water in nacre. The nanograin structure of nacre platelets, as well as the entrapped and adsorbed water, is two important contributors to the viscoelastic response of nacre. Atomic force microscopy experiments also indicate a very high force to remove organic from the aragonite in nacre. These experiments provide important insight into nanomechanical response of nacre, its constituents and also interfaces.
The excellent biocompatibility, biofunctionality, and non-antigenic property make chitosan an ideal material for tissue regeneration. In addition to that its hydrophilic surface promotes cell adhesion, proliferation, and differentiation, and evokes a minimal foreign body reaction on implantation. In spite of these favorable properties, the inadequate mechanical strength and loosening of structural integrity under wet conditions, limit its application for bone tissue engineering. To improve the suitability of chitosan for bone tissue engineering, we have biomimetically synthesized composites of chitosan, polygalacturonic acid and hydroxyapatite. Polygalacturonic acid (PgA) is biocompatible, biodegradable and electrostatically complementary to chitosan. The strong interactions between negatively charged carboxylate groups of PgA and positively charged amino groups of chitosan lead to complex formation. This biopolymer complex provides improved mechanical strength and better structural integrity under wet condition. In this study, we have investigated the applicability of chitosan-PgA-hydroxyapatite composites for bone tissue engineering.
The motivation for this study stems from the fact that there are no uniform criteria to identify the onset of the summer monsoon at a particular location. Furthermore, proper understanding of the events that culminate in the onset of the monsoon is crucial to allow its prediction over various time scales. An attempt is made to elucidate the characteristics of the onset and retreat of the monsoon using a global data assimilation and forecast system. For this purpose, the time series of net tropospheric large-scale budgets of kinetic energy, heat and moisture are examined over the Arabian Sea, Bay of Bengal and some land locations in India. The study makes use of daily data comprising operational analysis (0000 UTC) and forecasts (day1 through day5) produced by the National Centre for Medium Range Weather Forecasting, India, for the summer season of 1994.
The sequence of events associated with the advent of the monsoon is noticeably different at various locations. The horizontal fluxes of heat and moisture produce a divergence regime prior to the evolution and change to convergence during the onset of monsoon over the Arabian Sea. Similarly, intense diabatic cooling is noticed prior to the onset of mansoon and changes to heating subsequently. On the other hand, heat and moisture fluxes remain in the convergence regime well before the arrival of the monsoon over the Bay of Bengal. In turn, diabatic heating is noticed prior to the onset here. Onset characteristics at Bombay and Nagpur are similar to those of the Arabian Sea. However, features at Calcutta are identical to those over the Bay of Bengal. Further, the budgets of kinetic energy, heat and moisture depict monotonic decrease at various land locations corresponding to the retreat. Interestingly, the signature of retreat is very similar at the various locations considered here. These changes are observed in the analysis and further corroborated by the model forecasts. Despite the systematic biases, the model captures the essential signature of the onset at various forecast ranges.
Background and objective: Venous air embolism is a constant threat during neurosurgery performed in the sitting position. No large prospective study has compared the incidence of venous air embolism and associated hypotension between adults and children.
Methods: Four hundred and thirty patients (334 adults, 96 children) scheduled to undergo planned posterior fossa surgery in the sitting position (between January 1989 to December 1994) were studied with end-tidal carbon dioxide monitoring. Intraoperatively, a sudden and sustained decrease in end-tidal carbon dioxide tension of >0.7 kPa was presumed to be due to venous air embolism. Management during the episode was on the established guidelines. Hypotension (decrease in systolic arterial pressure of 20% or more from the previous level) was treated with crystalloids and/or a vasopressor.
Results: Capnometry detected a 28% incidence rate of air embolism in adults (93/334) and a 22% incidence rate in children (21/96) (P = 0.29). In both groups, the highest incidence rate of embolism took place during muscle handling (44% of adults versus 38% of children, P = 0.8). Embolic episodes were accompanied by hypotension in 37% of adults (34/93) and in 33% of children (7/21) (P = 0.98). To restore arterial pressure to pre-embolic levels, 53% of adults (18/34) and 43% of children (3/7) were administered vasopressors (P = 0.94). There was no intraoperative mortality. The surgical procedure on one adult was abandoned because of persistent hypotension following the embolic episode.
Conclusion: The incidence of venous air embolism and consequent hypotension is similar in adults and children.
A biomimetic process involving in situ mineralization of hydroxyapatite (HAP) is used to design new composite biomaterials for bone tissue engineering. Surface and bulk properties of HAP composites have been studied for hydroxyapatite mineralized in absence (ex situ) of polyacrylic acid (PAAc) and in presence (in situ) of PAAc. XRD studies show existence of structural disorder within in situ HAP. It has been observed that PAAc increases the rate of crystallization. FTIR studies indicate calcium deficiency in structure of both in situ and ex situ HAP. PAAc provides favorable sites for nucleation of HAP. During crystallization of HAP, PAAc dissociates to form carboxylate ion, which binds to HAP. Porous and solid composites of in situ and ex situ HAP with polycaprolactone (PCL) in 50:50 ratio have been made to evaluate their applicability as bone scaffold. Mechanical tests on solid samples indicate ex situ HAP/PCL composites have higher elastic modulus (1.16 GPa) than in situ HAP/PCL composites (0.82 GPa). However, in case of porous composites, in situ HAP/PCL composites are found to have higher elastic modulus (29.5 MPa) than ex situ HAP/PCL composites (10.4 MPa). Nanoindentation tests were also performed at different loads to evaluate mechanical properties of the composites. In situ HAP mineralized using non-degradable polymers has thus been shown to improve mechanical response in porous composites.
Eu3+ doped Y2O3 and Lu2O3 nanocrystalline powders were synthesized via combustion technique using urea as a fuel and the metal nitrates as oxidants. The compacted nanopowders were vacuum sintered in order to form the translucent ceramics. A significant enhancement of emission characteristics was observed from the ceramics synthesized from the nanoparticles by controlling the vacuum-sintering conditions. Although the processed ceramics display superior emission characteristics, the nanocrystalline phosphor powders also display reasonably good emission characteristics. Highly epitaxial Y2O3:Eu3+ and Lu2O3:Eu3+ films were deposited on various substrates under different growth and optimization conditions using pulsed-laser deposition technique using high-density translucent ceramic target. Superior spectroscopic performance was obtained on films grown on sapphire substrates due to high-quality and epitaxial nature of the film.
Cataract is a multifactorial disease. Osmotic stress, together with weakened antioxidant defence mechanisms, is attributed to the changes observed in human diabetic cataract. Epidemiological studies provide evidence that nutritional antioxidants slow down the progression of cataract. The usefulness of lycopene, a dietary carotenoid, in the pathogenesis of human cataracts has not been studied so far. Since the epithelium is the metabolic unit of the lens, the effect of lycopene on galactose-induced morphological changes and antioxidant status of human lens epithelial cells (HLEC) in culture was evaluated in the present study. HLEC of fresh cadaver eyes obtained from an eye bank were cultured in medium supplemented with fetal calf serum (200 ml/l). On confluency, the cells were subcultured in medium containing either 30 m-d-galactose or 30 mM-d-galactose + lycopene (5, 10 or 20 μM) for 72 h. The cells were observed under the phase-contrast microscope and transmssion electron microscope for any morphological changes and then harvested for the estimation of various biochemical variables. Malondialdeyde, glutathione and antioxidant enzymes were significantly altered in the control as compared with the normal cultures. Vacuolization was also observed in the presence of galactose. Addition of lycopene confers significant protection against these changes in HLEC.