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To measure and compare the skin doses received by treated left breast and contralateral breast (CB) during whole breast radiotherapy using five treatment techniques in an indigenously prepared wax breast phantom.
Materials and methods:
Computed tomography (CT) images of the breast phantom were used for treatment planning and comparison of skin dose calculated from treatment planning system (TPS) with measured dose. Planning target volume (PTV) and the CB were drawn arbitrarily on the CT images acquired for the breast phantom with 10 numbers of calibrated optically stimulated luminescent dosimeters (OSLDs) fixed on the surface of both breasts. The TPS calculated surface doses of PTV breast and CB for five treatment planning techniques, viz., conventional wedge (CW), irregular surface compensator-based (ISC), field-in-field (FiF), intensity-modulated radiotherapy (IMRT) and rapid arc (RA) techniques were obtained for comparison. The plans were executed in Clinac iX Linear Accelerator with the OSLDs fixed at the same locations on the phantom as in simulation. The TPS calculated mean dose at the surface of the treated left breast and CB was noted for the 10 OSLDs from dose-volume histogram (DVH) and compared with the measured dose. Also, the mean chamber dose at the centre of the left breast was noted from the DVH for comparing with ion chamber measured dose.
With reference to the results, it is seen that the dose to the CB is lowest in ISC technique and FiF technique and greatest in IMRT technique. The CW technique also delivered a dose comparable to IMRT to the CB of the phantom. The dose to the surface of PTV breast was highest and comparable in CW plans and FiF plans (68% and 67%) and lowest in IMRT and RA plans (50% each).
Analysis of the results shows that the FiF and ISC techniques are preferred while planning breast radiotherapy due to the reduced dose to the CB.
The eastern Arabian Sea is influenced by both the advection of upwelled water from the western Arabian Sea and winter convective mixing. Therefore, sediments collected from the eastern Arabian Sea can help to understand the long-term seasonal hydrographic changes. We used the planktonic foraminifera census and stable isotopic ratio (δ18O) from sediments drilled during the International Ocean Discovery Program Expedition 355 to reconstruct surface hydrographic changes in the eastern Arabian Sea during the last 350 kyr. The increased abundance of Globigerina bulloides suggests enhanced advection of upwelled water during the latter half of MIS7 and the beginning of MIS6, as a result of a strengthened summer monsoon. A large drop in upwelling and/or advection of upwelled water from the western Arabian Sea is inferred during the subsequent interval of MIS6, based on the rare presence of G. bulloides. The comparable relative abundance of Neogloboquadrina dutertrei, G. bulloides and Globigerinoides ruber suggests that during the early part of MIS5, hydrographic conditions were similar to today. The upwelling decreased and winter convection increased with the progress of the glacial interval. A good coherence between planktonic foraminiferal assemblage-based monsoon stacks from both the eastern and western Arabian Sea suggests a coeval response of the entire northern Arabian Sea to the glacial–interglacial changes. The glacial–interglacial difference in δ18Osw-ivc was at a maximum with 4–5 psu change in salinity during Termination 2 and 3, and a minimum during Termination 4. The significantly reduced regional contribution to the glacial–interglacial change in δ18Osw-ivc during Termination 4 suggests a lesser change in the monsoon.
A total of 45 strains of Vibrio cholerae O1 isolated from 10 different places in India where they were associated with cases of cholera between the years 2007 and 2008 were examined by molecular methods. With the help of phenotypic and genotypic tests the strains were confirmed to be O1 El Tor biotype strains with classical ctxB gene. Polymerase chain reaction (PCR) analysis by double – mismatch amplification mutation assay PCR showed 16 of these strains carried the ctxB-7 allele reported in Haitian strains. Sequencing of the ctxB gene in all the 45 strains revealed that in 16 strains the histidine at the 20th amino acid position had been replaced by asparagine and this single nucleotide polymorphism did not affect cholera toxin production as revealed by beads enzyme-linked immunosorbent assay. This study shows that the new ctxB gene sequence was circulating in different places in India. Seven representatives of these 45 strains analysed by pulsed – field gel electrophoresis showed four distinct Not I digested profiles showing that multiple clones were causing cholera in 2007 and 2008.
No existing models of alcohol prevention concurrently adopt universal and selective approaches. This study aims to evaluate the first combined universal and selective approach to alcohol prevention.
A total of 26 Australian schools with 2190 students (mean age: 13.3 years) were randomized to receive: universal prevention (Climate Schools); selective prevention (Preventure); combined prevention (Climate Schools and Preventure; CAP); or health education as usual (control). Primary outcomes were alcohol use, binge drinking and alcohol-related harms at 6, 12 and 24 months.
Climate, Preventure and CAP students demonstrated significantly lower growth in their likelihood to drink and binge drink, relative to controls over 24 months. Preventure students displayed significantly lower growth in their likelihood to experience alcohol harms, relative to controls. While adolescents in both the CAP and Climate groups demonstrated slower growth in drinking compared with adolescents in the control group over the 2-year study period, CAP adolescents demonstrated faster growth in drinking compared with Climate adolescents.
Findings support universal, selective and combined approaches to alcohol prevention. Particularly novel are the findings of no advantage of the combined approach over universal or selective prevention alone.
Most empirical studies into the covariance structure of psychopathology have been confined to adults. This work is not developmentally informed as the meaning, age-of-onset, persistence and expression of disorders differ across the lifespan. This study investigates the underlying structure of adolescent psychopathology and associations between the psychopathological dimensions and sex and personality risk profiles for substance misuse and mental health problems.
This study analyzed data from 2175 adolescents aged 13.3 years. Five dimensional models were tested using confirmatory factor analysis and the external validity was examined using a multiple-indicators multiple-causes model.
A modified bifactor model, with three correlated specific factors (internalizing, externalizing, thought disorder) and one general psychopathology factor, provided the best fit to the data. Females reported higher mean levels of internalizing, and males reported higher mean levels of externalizing. No significant sex differences emerged in liability to thought disorder or general psychopathology. Liability to internalizing, externalizing, thought disorder and general psychopathology was characterized by a number of differences in personality profiles.
This study is the first to identify a bifactor model including a specific thought disorder factor. The findings highlight the utility of transdiagnostic treatment approaches and the importance of restructuring psychopathology in an empirically based manner.
To report the International Nosocomial Infection Control Consortium surveillance data from 40 hospitals (20 cities) in India 2004–2013.
Surveillance using US National Healthcare Safety Network’s criteria and definitions, and International Nosocomial Infection Control Consortium methodology.
We collected data from 236,700 ICU patients for 970,713 bed-days
Pooled device-associated healthcare-associated infection rates for adult and pediatric ICUs were 5.1 central line–associated bloodstream infections (CLABSIs)/1,000 central line–days, 9.4 cases of ventilator-associated pneumonia (VAPs)/1,000 mechanical ventilator–days, and 2.1 catheter-associated urinary tract infections/1,000 urinary catheter–days
In neonatal ICUs (NICUs) pooled rates were 36.2 CLABSIs/1,000 central line–days and 1.9 VAPs/1,000 mechanical ventilator–days
Extra length of stay in adult and pediatric ICUs was 9.5 for CLABSI, 9.1 for VAP, and 10.0 for catheter-associated urinary tract infections. Extra length of stay in NICUs was 14.7 for CLABSI and 38.7 for VAP
Crude extra mortality was 16.3% for CLABSI, 22.7% for VAP, and 6.6% for catheter-associated urinary tract infections in adult and pediatric ICUs, and 1.2% for CLABSI and 8.3% for VAP in NICUs
Pooled device use ratios were 0.21 for mechanical ventilator, 0.39 for central line, and 0.53 for urinary catheter in adult and pediatric ICUs; and 0.07 for mechanical ventilator and 0.06 for central line in NICUs.
Despite a lower device use ratio in our ICUs, our device-associated healthcare-associated infection rates are higher than National Healthcare Safety Network, but lower than International Nosocomial Infection Control Consortium Report.
Infect. Control Hosp. Epidemiol. 2016;37(2):172–181
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.
Chemically deposited thin film stack of SnSe-ZnSe-Cu2-xSe was heated in nitrogen with Se vapor at 350-400 oC to produce Cu2ZnSnSe4 (CZTSe) thin films. For this, a thin film of SnSe with 180 nm thickness was deposited at 26 °C from a chemical bath containing tin(II) chloride, triethanolamine, sodium hydroxide, sodium selenosulfate, and a small quantity of polyvinylpyrrolidone. Thin films of ZnSe and Cu2-xSe were subsequently deposited on this SnSe film, also from chemical bath. The CZTSe thin film produced this way shows X-ray diffraction pattern matching that of Cu2ZnSnSe4 (kesterite/stannite) and have a Zn-rich composition. The film has an optical band gap of 0.9-1.0 eV and p-type electrical conductivity, 0.2-0.06 Ω-1 cm-1.
To develop a psychometrically valid questionnaire for testing knowledge on micronutrients and to assess the relationship between knowledge and biomarkers of micronutrient status among adolescents.
Cross-sectional, institution-based, validity and reliability study.
Seven higher secondary schools were covered in the limits of Greater Hyderabad Municipal Corporation, Hyderabad, India.
Students aged 15–19 years, n 92 for the pre-test, n 108 for test–retest and n 109 for studying the relationship between knowledge and biomarkers of Fe, retinol, ascorbic acid, α-tocopherol, folic acid and vitamin B12 status.
From an item pool of 106, thirty-one items were selected based on content validity. Statistical tools to obtain a valid and reliable questionnaire among adolescent boys and girls resulted in eighteen items with a difficulty index of 0·11–0·86, discrimination index of 0·20–0·72 and validity index (point bi-serial correlation) of 0·10–0·62. Reliability as measured by Cronbach's α was 0·71 and the intra-class correlation coefficient was 0·80. A Bland–Altman plot showed good agreement between test and retest scores. The mean response score to the eighteen-item questionnaire was 5·2 (sd 2·68). The mean values of serum retinol were significantly different (P = 0·022) between groups below (24·8 (sd 6·64) μg/dl) and above (28·0 (sd 7·67) μg/dl) the 50th percentile of knowledge score. The relationship persisted after controlling for economic status as a covariate using analysis of covariance (P = 0·018). Other micronutrients did not show any significant relationship.
A valid and reliable eighteen-item knowledge questionnaire was constructed and found to have a significant positive relationship with plasma retinol status alone.
New variants of Vibrio cholerae O1 have appeared in different time-frames in various endemic regions, especially in Asia and Africa. Sixty-nine strains of V. cholerae O1 isolated in Zambia between 1996 and 2004 were investigated by various genotypic techniques to determine the lineage of virulence signatures and clonality. All strains were positive for Vibrio seventh pandemic Islands (VSP)-I and VSP-II and repeat toxin (RTX) gene clusters attesting their El Tor lineage. Interestingly, strains isolated in recent times (2003–2004) were identified as an altered variant (El Tor biotype that harbours El Tor type rstR but produce classical ctxB) that replaced completely the progenitor El Tor strains prevalent in 1996–1997. Recent altered variant strains differed from prototype El Tor strains isolated earlier in that these strains lacked two ORFs, VC0493 and VC0498, in the VSP-II region. PFGE analysis revealed two major clonal lineages in the strains; cluster A represented the strains isolated before 2003 and cluster B the altered strains isolated in 2003–2004. Cluster A was closely related to prototype El Tor reference strain isolated in Bangladesh in 1971. Cluster B was found to be matched with Bangladeshi altered strains but was different from the hybrid strains isolated from Mozambique and Bangladesh. This report provides important information on the genesis of altered strains of V. cholerae O1 isolated in Zambia and emphasizes the need for further studies to follow the trends of evolutionary changes.
The paper discusses the results of a study on the formation of indium oxide
nanoclusters in silica samples implanted with high energy indium ions. Trace
quantities of indium oxide were found on as-implanted samples. On annealing
in vacuum/oxygen atmosphere significant increase in the quantity of indium
oxide phase was observed. A mechanism is proposed for the formation of
indium oxide and is mainly attributed to the reaction of metallic indium
with the oxygen released from the silica matrix by ballistic process. During
annealing in oxygen atmosphere the oxygen diffusing into the silica also
plays a role in the oxidation of indium NCs.
Over a 2-year period, 25 families comprising of 181 individuals of all ages were longitudinally observed for the excretion of Campylobacter species. Faecal samples were taken from all persons with diarrhoea. Specimens were also taken from apparently healthy individuals and from domestic animals living within the confines of the study families at monthly intervals.
The overall diarrhoea attack rate was 19 episodes per 100 person-years with peak incidence in the 1- to 4-year-old age group (76/100 person-years). Eight (11·5%) of the total episodes were campylobacter-associated and the overall rate of campylobacter positive diarrhoeal episodes were 2·2 per 100 person-years. Of the 1002 stool samples from healthy individuals 32 (3·2/100 samples) were positive for campylobacter. The organism was most frequently isolated from children under 1 year of age both during diarrhoeal episodes (11·5 per 100 person-years) and non-diarrhoeal (11·1 per 100 samples). Multiple infections in a family were rare. In 19·4% of the occasions one or more animals were campylobacter positive. However, only in 7·7% of these occasions was a human infection recorded within 1 month after the animal was found to be positive.
The study showed that the epidemiology of campylobacteriosis in this community was distinct compared to that observed in developed countries.
The distribution and virulence of Vibrio cholerae serogroups other than O1 and O139 in India before, during and after the advent of O139 serogroup was investigated. A total of 68 strains belonging to 31 different ‘O’ serogroups were identified during the study period. With the exception of O53, there was no spatial or temporal clustering of any particular non-O1 non-O139 serogroup at any given place. Two of the 68 strains examined produced cholera toxin (CT) which could only be partially absorbed with anti-CT immunoglobulin G. Tissue culture assay revealed that some of the non-O1 non-O139 strains produced factors which evoked either a cell rounding or cell elongation response depending upon the medium used. This study indicates that serogroups other than O1 and O139 should also be continuously monitored.
Fourteen strains of S. Typhi (n=13) and S. Paratyphi A (n=1) resistant to ciprofloxacin were compared with 30 ciprofloxacin decreased-susceptibility strains on the basis of qnr plasmid analysis, and nucleotide substitutions at gyrA, gyrB, parC and parE. In ciprofloxacin-resistant strains, five S. Typhi and a single S. Paratyphi A showed triple mutations in gyrA (Ser83→Phe, Asp87→Asn, Glu133→Gly) and a novel mutation outside the quinolone resistance determining region (QRDR) (Met52→Leu). Novel mutations were also discovered in an isolate (minimum inhibitory concentration 8 μg/ml) in gyrA gene Asp76→Asn and outside the QRDR Leu44→Ile. Out of 30 isolates with reduced susceptibility, single mutation was found in 12 strains only. Genes encoding qnr plasmid (qnr A, qnr B, AAC1-F) were not detected in ciprofloxacin-resistant or decreased-susceptibility strains. Antimicrobial surveillance coupled with molecular analysis of fluoroquinolone resistance is warranted for reconfirming novel and established molecular patterns of resistance, which is quintessential for reappraisal of enteric fever therapeutics.
We report photovoltaic cell structures on SnO2:F (TCO) coated glass substrates. Thin films of CdS, SnS, and CuS or PbS were deposited sequentially from chemical baths to produce the solar cell structures: SnO2:F-CdS- SnS (A)-CuS-Ag; SnO2:F-CdS- SnS (A)-PbS-Ag; and SnO2:F-CdS- SnS (B)-PbS-Ag. Heating SnS-CuS films results in the formation of Cu2SnS3, and sequential depositions of SnS and PbS to obtain solar cells produce stratified layers as required for solar cells. The photovoltaic characteristics, Voc 340 mV and Jsc 6 mA/cm2 in these structures suggest that absorber thin films based on tin sulfide are worth investigating as a relatively abundant and non-toxic material for solar cells.
CdS and PbS are well known semiconductor materials. Starting in 1969 and into 1970's CdS-PbS cells were reported with open circuit voltage (Voc) up to 450 mV and short circuit current density (Jsc) < 1 mA/cm2. However, further reports are scarce. These two materials are also the most investigated by chemical deposition technique. In this work we revisit this type of photovoltaic junctions and present the photovoltaic behavior of distinct type of cell structures prepared by chemical deposition: glass/CdS/PbS/Ag, SnO2:F/CdS/PbS/Ag, and SnO2:F/CdS/(Bi2S3 or/and CdSe)/PbS/Ag. Depending on the cell type, Voc of > 500 mV or Jsc of > 3 mA/cm2 could be obtained under illumination of 1-3 kW/m2. This work opens up possibilities for developing simple solar cell structures by sequential chemical deposition of semiconductors.
Solar cell structures with Sb2SxSe3-x and PbS as absorber layers were fabricated by chemical deposition on commercial transparent conductive oxide coated glass. The solid solution here was prepared by heating at 250°C a Sb2S3 thin film in contact with a chemically deposited Se-thin film. It has a graded band gap of 1-1.8 eV. A PbS thin film deposited on this layer basically fulfils the role of a p+ layer; its role as an absorber is yet to be studied. Open circuit voltage of 560 mV and short circuit current density ¡Ö 1mA/cm2under 1-3 kW/m2 tungsten halogen radiation are characteristics of these cells. Optimization of the film thicknesses and heating may offer prospects for these materials toward alternate thin film solar cell technology.