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1.1. Definition. Let λ ≡ λ(ω) be continuous, differentiable, and monotonic increasing in (0, ∞) and let it tend to infinity as ω → ∞. Suppose that ∑ an (we write ∑ for throughout the present paper) is a given infinite series and let
The series ∑ an is said to be summable |R, λ, r|, where r > 0, if
where A is a fixed positive number (6, Definition B). Now, for r > 0, m < ω < m + 1,
Hence, ∑ an is summable |R, λ, r|, where r > 0, if
Experiments were carried out to determine methane (CH4) consumption in different soil (vertisol) aggregates under elevated carbon dioxide (eCO2) and temperature. Soil aggregates of <0·25 mm diameter (microaggregates), 0·25–1 mm diameter (mesoaggregates) and 1–2 mm diameter (macroaggregates) were incubated under different CO2 (400, 800 and 1200 µm/m or ppm CO2) and temperature (25, 35 and 45 °C) conditions. Methane consumption was high in mesoaggregates and low in microaggregates under ambient CO2 and temperature (25 °C). However, eCO2 and temperature significantly inhibited CH4 consumption and decreased culturable microbial numbers. Methane consumption in mesoaggregates was inhibited by 21–66% at 800–1200 ppm of CO2. Principal component analysis designated soil aggregate size as the most important component of variation, followed by temperature and CO2. Ordination biplot indicated eCO2 and temperature impacted negatively on CH4 consumption and culturable methanotrophs. Results highlighted that mesoaggregates of 0·25–1·00 mm are hotspots for CH4 consumption and that rising atmospheric CO2 and temperature may inhibit CH4 consumption significantly in a tropical vertisol.
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.
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.
Large areas of rainfed lowlands of Asia annually experienced flash flooding during the rice-growing season, which is an important abiotic stress that adversely affect grain yield of rice (Oryza sativa L.) crop. Submergence stress is a common environmental challenge for agriculture sustainability in these areas because lack of high-yielding, flood-tolerant cultivars. In this study, IR64-Sub1 and IR64 were compared for their tolerance to submergence at active tillering (AT), panicle initiation (PI) and heading (H) stages with nitrogen and phosphorus application time. We evaluated the role of cultivars, stage of submergence and N and P application on phenology, leaf senescence (LS), photosynthetic (Pn) rate, yield attributes and yield. Under non-submerged conditions, no difference was observed in phenology, Pn rate and yield of both cultivars. Submergence substantially reduced biomass, Pn rate, yields attributes and yield across cultivars with more drastic reduction in IR64. Submergence at H stage proves to be most detrimental. Nitrogen application after desubmergence with basal P improved the Pn rate resulting in significantly higher yield and yield components. Nitrogen application before submergence resulted in increased LS and ethylene accumulation in shoots leading to drastic reduction in growth, Pn rate and yield. Crop establishment and productivity could therefore be enhanced in areas where untimely flooding is anticipated by avoiding N application before submergence and applying N after desubmergence with basal P (phosphorus).
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.
In this article, we present two new novel finite difference approximations of order two and four, respectively, for the three dimensional non-linear triharmonic partial differential equations on a compact stencil where the values of u, ∂2u/∂n2 and ∂4u/∂n4 are prescribed on the boundary. We introduce new ideas to handle the boundary conditions and there is no need to discretize the derivative boundary conditions. We require only 7- and 19-grid points on the compact cell for the second and fourth order approximation, respectively. The Laplacian and the biharmonic of the solution are obtained as by-product of the methods. We require only system of three equations to obtain the solution. Numerical results are provided to illustrate the usefulness of the proposed methods.
Surface and chemomechanical effects are very important in tribology, wear and friction, but are difficult to quantify due to being confined in the near-surface region. Nanoindentation techniques have been successfully used to investigate environmental effects on mechanical response. In this work, nanoindentation tests have been performed on various materials (silicon, fused silica, and gold nanofilms on a glass substrate) immersed in long-chain alcohols (i.e., 1-hexanol, 1-heptanol, 1-octanol, and 1-nonanol). The results consistently show an increase in mechanical properties for silicon and gold nanofilms immersed in the alcohols at shallow nanoindentation depths. The results for fused silica show little effect of immersion. The changes in the observed mechanical properties are attributed to the ability of the long-chain organic molecules to sustain elastic strains when they are in confined geometry. These long organic chains also distribute the normal stress of the indenter over a larger area on the sample surface thereby causing a decrease in the perceived contact area (Ac). As a result the long-chain alcohols modify both the Ac and the elastic compliance of the contact.
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.
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.
Khandesh region in Maharashtra is an extensive plain interspersed with ranges of hills. It is nearly surrounded by broad chains of mountains covered with vegetation. It was inhabited by the Bhils. They lived in hovels which often crested the tops of isolated hills where approach was immediately discovered and easily defended. They shifted to new habitats after a few weeks or months. Turbulent by disposition and skilful hunters by necessity, they obtained their supplies of roots, berries and game from the jungles. As Captain D. C. Graham put it, ‘To barter anything but what was reaped by the hand of violence was an offence against the tribe; to cultivate or engage in mechanical craft deeply degrading; and no employment was considered to be correct which in any way interfered with the cherished burden of the long-bow, and the ponderous sheaf of arrows’.
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.
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.
In this study a non-hydrostatic version of the PSU/NCAR mesoscale model is used to simulate an active western disturbance (WD) that affected the Indian region in January 1997. The role of the planetary boundary layer (PBL) and convection parameterisation schemes in the development of the WD is investigated. Analysis and predictions for some fields, including sea level pressure, geopotential height, temperature, horizontal wind and precipitation are examined. Some statistical scores are also calculated and compared. It is found that the performance of the Hong-Pan (as implemented in the NCAR MRF model) and Betts-Miller (or Grell) schemes as PBL and convection parameterisation schemes respectively are best compared to the other schemes used in this study.
The natural history of human filarial infections leading to development of disease has been a subject of intense debate. The models proposed so far have largely been based on cross-sectional data on microfilariae (Mf) and disease prevalence in filariasis endemic areas. In an attempt to study the parasitological and clinical consequences of filarial infection in Beldal (Orissa, India), an area endemic for Bancroftian filariasis, cohorts of 59 asymptomatic Mf carriers (AS) and 187 asymptomatic and amicrofilaraemic subjects or ‘endemic normals’ (‘EN’), were followed-up and a fraction (73% and 46% respectively) re-examined after 13 years to monitor (a) Mf prevalence, (b) Mf density, (c) circulating filarial antigen (CFA) and (d) chronic disease manifestations. The Mf prevalence and density were also monitored in Mf carriers after 1 and 4 years. Both Mf prevalence and density decreased progressively in the cohort of Mf carriers over a period of 13 years in Beldal. Only 37% of them continued to be microfilaraemic and the Mf density in these subjects was only 10% of the original level. However, loss of circulating Mf in this cohort did not result in loss of CFA and 95% remained CFA positive regardless of Mf status. About 23% of males in the ‘EN’ cohort developed hydrocoele while only 5·7% of male Mf carriers, who were not treated with DEC, had developed hydrocoele after 13 years. A cohort of Mf carriers in another area, Jatni, was also examined after 10 years to study the parasitological and clinical outcome. In this area, about 59% of the Mf carriers continued to be microfilaraemic after 10 years. These results reveal that in Mf carriers adult filarial worms persist for several years and that loss of circulating Mf with or without chemotherapy with DEC (single 12-day course) does not influence adult worm survival. The findings have been discussed in the context of ‘static’ and ‘dynamic’ models describing the relationship between infection and disease in human filariasis.
There is considerable controversy surrounding the optimum treatment of advanced hypopharyngeal cancers. Curative radiotherapy with surgical salvage in reserve is an accepted protocol as is also a combined treatment of surgery and radiotherapy. The present study is a retrospective analysis of the survival results of 195 cases treated in a single centre. The combined surgery and radiotherapy group comprised a greater number of pyriform fossa and post-cricoid tumours whereas, the curative radiotherapy group had a higher proportion of posterior pharyngeal wall tumours. Actuarial two-year disease-free survival rates were significantly better with combined treatment when results of stage III and IV lesions (164 patients) of all sites are taken together, as compared to those obtained with curative radiotherapy without salvage (p = 0.000) or radiotherapy with surgical salvage for residual/recurrent tumours (p = 0.0021).
A total of 110 cattle were examined in an area endemic for Bancroftian filariasis for the prevalence of infection of the bovine filarial parasite Setaria digitata. About 12.5% of cattle were found to harbour both adult worms in the peritoneum and microfilariae (mf) in circulation; 70% of the cattle were amicrofilaraemic but with an adult worm infection. A third group of cattle (16.5%) was free of detectable mf and adult worms. The presence of adult worms and/or mf did not influence the antibody levels to any of the four antigen preparations of S. digitata. However, there was a significant inverse relationship between the presence of antibodies to microfilarial sheaths and the absence of circulating mf as shown by the immunoperoxidase assay. Cattle immunoglobulin containing high titres of anti-sheath antibodies cleared circulating microfilariae very effectively in Mastomys coucha thus demonstrating the protective nature of anti-sheath antibodies in eliminating circulating microfilariae in vivo.