3,295 research outputs found
Solar Neutrinos: Status and Prospects
We describe the current status of solar neutrino measurements and of the
theory -- both neutrino physics and solar astrophysics -- employed in
interpreting measurements. Important recent developments include
Super-Kamiokande's determination of the neutrino-electron elastic scattering
rate for 8B neutrinos to 3%; the latest SNO global analysis in which the
inclusion of low-energy data from SNO I and II significantly narrowed the range
of allowed values for the neutrino mixing angle theta12; Borexino results for
both the 7Be and pep neutrino fluxes, the first direct measurements
constraining the rate of ppI and ppII burning in the Sun; global reanalyses of
solar neutrino data that take into account new reactor results on theta13; a
new decadal evaluation of the nuclear physics of the pp chain and CNO cycle
defining best values and uncertainties in the nuclear microphysics input to
solar models; recognition of an emerging discrepancy between two tests of solar
metallicity, helioseismological mappings of the sound speed in the solar
interior, and analyses of the metal photoabsorption lines based on our best
current description of the Sun's photosphere; a new round of standard solar
model calculations optimized to agree either with helioseismology or with the
new photospheric analysis; and, motivated by the solar abundance problem, the
development of nonstandard, accreting solar models, in order to investigate
possible consequences of the metal segregation that occurred in the proto-solar
disk. We review this progress and describe how new experiments such as SNO+
could help us further exploit neutrinos as a unique probe of stellar interiors.Comment: 82 pages, 11 figure
Nitrogen and sulphur fertiliser management to achieve grain protein quality targets of high-yielding modern winter milling wheat. AHDB Project Report No. 642
Nitrogen and sulphur fertiliser management to achieve grain protein quality targets of high-yielding modern winter milling wheat. AHDB Project Report No. 642
Ablative therapy for people with localised prostate cancer: a systematic review and economic evaluation
© Queen’s Printer and Controller of HMSO 2015.Background People diagnosed with cancer of the prostate, a sex gland in the pelvis, have a choice of treatment options depending on the severity of disease. For people whose cancer is at medium and low risk of spread, the main options are surgical removal of the prostate, radical prostatectomy (RP), use of external beam radiotherapy (EBRT) to destroy the cancer or delaying treatment until there are signs that the cancer is getting worse [active surveillance (AS)]. RP and radiotherapy are effective at curing the cancer but may also cause long-term urinary incontinence and sexual problems. AS, on the other hand, may be quite difficult for people to cope with as they know that the cancer is still present. Newer treatments aim to target the disease more precisely so that surrounding normal tissues can be preserved, reducing the risk of side effects but still effectively destroying the cancer. These more targeted ablative therapies include cryotherapy, high-intensity focused ultrasound (HIFU), brachytherapy, photodynamic therapy (PDT), radiofrequency interstitial tumour ablation (RITA) and laser therapy, among others. Aims This study aimed to develop clinical care pathways relevant to a UK NHS context review systematically the evidence of the clinical effectiveness and safety of each newer ablative therapy concerning primary and salvage treatment of localised prostate cancer• determine which therapies are most likely to be cost-effective for implementation in the UK NHS identify and prioritise future research needs. Methods Clinical effectiveness review We conducted two discrete systematic reviews: (a) primary ablative treatment of localised prostate cancer compared with AS, RP or EBRT (b) salvage ablative treatment for local prostate cancer relapse after primary EBRT compared with salvage RP. MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Bioscience Information Service (BIOSIS), Science Citation Index, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), Database of Abstracts of Reviews of Effects (DARE) and the Health Technology Assessment (HTA) databases were searched to the end of March 2013. Reference lists of all included studies were scanned and experts on our advisory panel were contacted for details of additional reports. Evidence came from randomised controlled trials (RCTs), non-randomised comparative studies (NRCSs) (if no RCT evidence was identified) and single-arm cohort studies (case series) with greater than 10 participants for the ablative procedures only. Conference abstracts or non-English-language reports were excluded. For the primary therapy systematic review, the ablative therapies considered were cryotherapy, HIFU, PDT, RITA, laser ablation and brachytherapy. The comparators were AS, RP and EBRT. For the salvage therapy systematic review, the ablative therapies considered were cryotherapy and HIFU. The comparator was RP. Outcomes were cancer related, adverse effects (functional and procedural) and quality of life. Two reviewers extracted data and carried out quality assessment. For meta-analysis, a Bayesian indirect mixed-treatment comparison was used. Cost-effectiveness The cost-effectiveness of the different treatments and their subsequent care pathways was assessed using a modified Markov individual simulation model, applied to a UK NHS setting. The perspective for the model was a health services perspective. Parameter estimates were derived from the systematic review of clinical effectiveness, a micro-costing exercise, other literature, the expert advisory group and other UK sources. The outputs of the model were costs and quality-adjusted life-years (QALYs) for each procedure, incremental costs and QALYs and incremental cost per QALY over the remaining lifetime. Both costs and QALYs were discounted at 3.5%. An elasticity analysis, together with probabilistic and deterministic sensitivity analyses, were performed to explore the uncertainty surrounding parameter estimates. Results Clinical effectiveness Cryotherapy Data from 3995 patients who received cryotherapy across 19 studies (1 RCT, 4 NRCSs and 14 case series) were included, with most studies considered to be at high risk of bias. In the short term, there was conflicting evidence relating to cancer-specific outcomes when cryotherapy was compared with either EBRT or surgery. The only finding that reached statistical significance was 1-year disease-free survival, which was worse for cryotherapy than for either EBRT or RP. However, none of the other cancer-specific outcomes, such as biochemical failure or overall survival, showed any significant differences between them. The findings in relation to cancer-specific outcomes are best regarded as inconclusive. There was evidence that the rate of urinary incontinence at 1 year was lower for people undergoing cryotherapy than for those undergoing RP [3% vs. 66%; odds ratio (OR) 0.02, 95% credible interval (CrI) < 0.01 to 0.34], but the size of the difference decreased with longer follow-up. There was a general trend for cryotherapy to have fewer procedural complications, apart from urinary retention. The only difference that reached statistical significance was for urethral stricture, which was less frequent after cryotherapy than after RP (1% vs. 8%; OR 0.24, 95% CrI 0.09 to 0.54). High-intensity focused ultrasound Data from 4000 patients who received HIFU across 21 studies (1 NRCS and 20 case series) were included, with all studies considered to be at high risk of bias. There was some evidence that biochemical failure rates were higher at 1 year when using HIFU than when using EBRT, and this was statistically significant. However, the difference was no longer statistically significant at 5 years. Similar findings were observed with regard to disease-free survival at 1 year, with worse outcomes for HIFU than for EBRT, which were statistically significant. The differences were no longer significant at 3 years. The biochemical result was in contrast to overall survival at 4 years, which was higher when using HIFU. There were insufficient data on any urinary incontinence, erectile dysfunction or bowel problems to draw any robust conclusions, although at 1 year HIFU had lower incontinence rates than RP (10% vs. 66%; OR 0.06, 95% CrI 0.01 to 0.48). The safety profile for HIFU was generally good, apart from a potential numerical increase in rates of urinary retention and dysuria. However, HIFU appeared to have a slightly higher incidence of urethral stricture than EBRT, and the difference was statistically significant (8% vs. 1%; OR 5.8, 95% CrI 1.2 to 24.5). Brachytherapy This review considered data from 26,129 patients who received brachytherapy across 40 studies (2 RCTs and 38 NRCSs), with most studies considered to be at high risk of bias. The data for brachytherapy were generally more robust than for other ablative therapies. In the short term, there was some evidence at 5-year follow-up that the rate of biochemical failure was lower for brachytherapy (7%) than for EBRT (13%; OR 0.46, 95% CrI 0.32 to 0.67) or RP (11%; OR 0.35, 95% CrI 0.21 to 0.56). There was also some evidence that disease-free survival was better for brachytherapy at 3-year follow-up. There was evidence that the rate of urinary incontinence up to 5 years after treatment was lower for people undergoing brachytherapy than for RP, but the size of the difference decreased with longer follow-up. There was also a trend towards lower erectile dysfunction rates for brachytherapy than for EBRT or RP and this reached statistical significance at 3 years after treatment (60% vs. 81% for EBRT and 88% for RP). There were insufficient data to draw any conclusions on bowel problems. The findings regarding procedural complications were mixed. Dysuria rates were higher for brachytherapy and this reached statistical significance when compared with RP. Urinary retention was also statistically significantly higher for brachytherapy than for EBRT. Stricture rates for brachytherapy were higher than those for EBRT, but lower than those for RP. The differences for stricture reached statistical significance when compared with RP. For rectal pain, there was evidence that rates were significantly lower for brachytherapy than for EBRT. Acute genitourinary toxicity, though rare, had statistically higher rates for brachytherapy than for EBRT, but acute gastrointestinal toxicity was lower for brachytherapy. Other ablative therapies Only two other ablative therapies were identified in the review: focal laser ablative therapy and PDT. Data were too scarce (a total of 35 participants for these two procedures) for any conclusions. Salvage therapy Data from 400 participants who were treated with salvage therapy following primary EBRT across nine case series were included. Six studies involved salvage RP, two involved salvage cryotherapy and one involved salvage HIFU. In six studies, data were not collected prospectively, and only short-term outcomes were reported. As such, all of the studies were considered as having a high risk of bias. There was no robust evidence that mortality or other cancer-specific outcomes differed between salvage cryotherapy and salvage RP in the short term. There were no data on cancer-specific outcomes for salvage HIFU. In regard to functional and quality of life outcomes, lack of data prevented any conclusions. In terms of adverse event outcomes, salvage cryotherapy had numerically fewer periprocedural complications (especially for bladder neck stenosis) than salvage HIFU or salvage RP, but there was a high level of uncertainty with this observation. Focal ablation Descriptive subgroup assessment within studies reporting the use of focal ablation was limited, but suggested that cancer-specific outcomes were at least comparable with those seen in full-gland therapy studies. Urinary incontinence rates may be lower following focal ablation, but the evidence is weak in light of the poor quality and quantity of the data. Active surveillance Lack of outcome data prevented comparison of the efficacy of ablative therapies with a programme of AS, apart from the rate of erectile dysfunction at 12 months, where there was no statistically significant difference. Cost-effectiveness Assuming equal recurrence in line with the lack of statistical differences from the effectiveness review, EBRT was the least costly (£19,363 per patient) and least effective (3.63 QALYs), whereas HIFU was more costly (£19,860 per patient) and more effective (3.86 QALYs). HIFU was more effective and less costly than the other newer ablative interventions. The lifetime incremental cost per QALY for HIFU compared with EBRT was £2915. There was a 75% chance that HIFU would be considered cost-effective at a £30,000-per-QALY threshold. In a plausible best-and-worst-case analysis, the probability that HIFU would be considered cost-effective varied between 60% and 70%. Strengths and limitations The main strength of the study was the systematic approach taken to review the literature and the inclusion of a relatively large quantity of studies, giving a high total number of participants. The main limitations were the low quantity and poor quality of the data available on cancer-related outcomes and long-term adverse events of urinary incontinence, sexual and bowel dysfunction, and the changing technology over the review period. Many published studies were poorly reported or lacked sufficient detail. Inconsistency in outcome definition, measurement and reporting was also a significant problem, and much of the information available was unsuitable for meta-analysis. Another major limitation resulted from the majority of comparisons being made using case series, with few head-to-head comparisons of ablative therapies against current practice. The estimates were therefore generated using indirect comparisons. Like all analyses, they require assumptions to be made that may or may not be reasonable. Accordingly, the results should be interpreted with a large degree of caution. Despite the considerable efforts to construct a model and seek the best data available, the lack of effectiveness data had implications for the economic evaluation. The limited data meant that there was insufficient evidence to assume that there was any difference between interventions for a number of parameters, a particular issue for biochemical recurrence, which was a key parameter in the evaluation. The impact of these assumptions was explored in sensitivity analyses. Conclusions Implications for health care For primary ablative therapy, neither cryotherapy nor HIFU had sufficiently robust data to enable any definitive conclusions to be made. The effectiveness data on brachytherapy were more robust and there was some evidence that cancer-specific outcomes in the short term were either better or equivalent to either EBRT or RP, with comparable adverse effect profiles apart from a possible increased risk of dysuria and urinary retention. The findings on focal ablative therapy were mostly derived from data on focal cryotherapy, which suggested that cancer-specific outcomes were at least comparable with those of full-gland cryotherapy, and there was a suggestion that the urinary incontinence outcome may be better following focal cryotherapy than whole-gland cryotherapy. The cost-effectiveness analysis confirmed the uncertainty from the clinical review and that there is no technology which appears superior, on the basis of current evidence, in terms of average cost-effectiveness. The probabilistic sensitivity analyses suggest that a number of ablative techniques are worthy of further research. For salvage ablative therapy following primary EBRT, a lack of reliable and robust data prevented any meaningful conclusions from being made, in comparison with salvage RP. The findings from the review indicate that there is insufficient evidence to help inform recommendations on the use of ablative therapies in the UK NHS. Need for further research The main gaps in the evidence base are the lack of direct comparative studies of ablative therapies; the consequent lack of robust data to inform calculations of cost-effectiveness and the role of focal ablative therapies; and the lack of longer-term data on cancer control, such as overall and cancer-specific mortality. The key research recommendations, in order of importance, are as follows: 1. HIFU and brachytherapy seem the most promising newer interventions but they lack high-quality evaluation. Such evaluation should ideally be by multicentre RCT with long-term follow-up, and would include predefined assessment of cancer-specific, dysfunction and health-related quality-of-life measures. Such studies should incorporate economic evaluations and also inform economic modelling
A preliminary study of the effect of closed incision management with negative pressure wound therapy over high-risk incisions
Background
Certain postoperative wounds are recognised to be associated with more complications than others and may be termed high-risk. Wound healing can be particularly challenging following high-energy trauma where wound necrosis and infection rates are high. Surgical incision for joint arthrodesis can also be considered high-risk as it requires extensive and invasive surgery and postoperative distal limb swelling and wound dehiscence are common. Recent human literature has investigated the use of negative pressure wound therapy (NPWT) over high-risk closed surgical incisions and beneficial effects have been noted including decreased drainage, decreased dehiscence and decreased infection rates. In a randomised, controlled study twenty cases undergoing distal limb high-energy fracture stabilisation or arthrodesis were randomised to NPWT or control groups. All cases had a modified Robert-Jones dressing applied for 72 h postoperatively and NPWT was applied for 24 h in the NPWT group. Morphometric assessment of limb circumference was performed at six sites preoperatively, 24 and 72 h postoperatively. Wound discharge was assessed at 24 and 72 h. Postoperative analgesia protocol was standardised and a Glasgow Composite Measure Pain Score (GCPS) carried out at 24, 48 and 72 h. Complications were noted and differences between groups were assessed.
Results
Percentage change in limb circumference between preoperative and 24 and 72 h postoperative measurements was significantly less at all sites for the NPWT group with exception of the joint proximal to the surgical site and the centre of the operated bone at 72 h. Median discharge score was lower in the NPWT group than the control group at 24 h. No significant differences in GCPS or complication rates were noted.
Conclusions
Digital swelling and wound discharge were reduced when NPWT was employed for closed incision management. Larger studies are required to evaluate whether this will result in reduced discomfort and complication rates postoperatively
Hsmar1 transposition is sensitive to the topology of the transposon donor and the target
Hsmar1 is a member of the Tc1-mariner superfamily of DNA transposons. These elements mobilize within the genome of their host by a cut-and-paste mechanism. We have exploited the in vitro reaction provided by Hsmar1 to investigate the effect of DNA supercoiling on transposon integration. We found that the topology of both the transposon and the target affect integration. Relaxed transposons have an integration defect that can be partially restored in the presence of elevated levels of negatively supercoiled target DNA. Negatively supercoiled DNA is a better target than nicked or positively supercoiled DNA, suggesting that underwinding of the DNA helix promotes target interactions. Like other Tc1-mariner elements, Hsmar1 integrates into 5′-TA dinucleotides. The direct vicinity of the target TA provides little sequence specificity for target interactions. However, transposition within a plasmid substrate was not random and some TA dinucleotides were targeted preferentially. The distribution of intramolecular target sites was not affected by DNA topology
Identification of Escherichia coli strains from water vending machines of Kelantan, Malaysia using 16S rRNA gene sequence analysis
Water vending machines provide an alternative source of clean and safe drinking water to the consumers. However, the quality of drinking water may alter due to contamination from lack of hygienic practices and maintenance of the machines. Hence, this study was conducted to determine the microbiological quality of water from vending machines and associated contact surfaces. Seventeen water samples and 85 swab samples (nozzles, drip trays, coin slots, buttons and doors) from 3 locations in Kelantan were collected. Polymerase chain reaction amplification and 16S ribosomal ribonucleic acid (rRNA) sequencing were carried out and sequences obtained were compared against the sequences available in the National Centre for Biotechnology Information database using the basic local alignment search tool programme. Coliform counts were observed in 94.12 % of water samples, 76.47 % of nozzles and 82.35 % of drip tray swabs. Furthermore, results of 16S rRNA sequence analysis indicated that two gram-negative isolates were identified as Escherichia coli U 5/41 (Accession no. NR_024570.1) and E. coli O157:H7 EDL933 (Accession no. CP008957.1) with similarity value of 100 %, respectively. The results from this study further improve our understanding of the potential microorganisms in drinking water. Regular maintenance and cleaning of water vending machines are important to reduce bacterial growth and the presence of waterborne pathogens
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Biomarker-based prediction of inflammatory bowel disease-related colorectal cancer: a case–control study
Regular colonoscopic surveillance for detection of dysplasia is recommended in longstanding inflammatory bowel disease (IBD), however, its sensitivity is disputed. Screening accuracy may increase by using a biomarker-based surveillance strategy.A case-control study was performed to determine the prognostic value of DNA ploidy and p53 in IBD-related neoplasia. Cases with IBD-related colorectal cancer (CRC), detected in our surveillance program between 1985-2008, were selected and matched with two controls, for age, gender, disease characteristics, interval of follow-up, PSC, and previous surgery. Biopsies were assessed for DNA ploidy, p53, grade of inflammation and neoplasia. Progression to neoplasia was analyzed with Cox regression analysis, adjusting for potentially confounding variables.Adjusting for age, we found statistically significant Hazard ratios (HR) between development of CRC, and low grade dysplasia (HR5.5; 95%CI 2.6-11.5), abnormal DNA ploidy (DNA index (DI) 1.06-1.34, HR4.7; 95%CI 2.9-7.8 and DI>1.34, HR6.6; 95%CI 3.7-11.7) and p53 immunopositivity (HR3.0; 95%CI 1.9-4.7) over time. When adjusting for all confounders, abnormal DNA ploidy (DI 1.06-1.34, HR4.7; 95%CI 2.7-7.9 and DI>1.34, HR5.0; 95%CI 2.5-10.0) and p53 immunopositivity (HR1.7; 95%CI 1.0-3.1) remained statistically significant predictive of neoplasia. In longstanding IBD, abnormal DNA ploidy and p53 immunopositivity are important risk factors of developing CRC. The yield of surveillance may potentially increase by adding these biomarkers to the routine assessment of biopsies
Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo
We use data from the second science run of the LIGO gravitational-wave
detectors to search for the gravitational waves from primordial black hole
(PBH) binary coalescence with component masses in the range 0.2--.
The analysis requires a signal to be found in the data from both LIGO
observatories, according to a set of coincidence criteria. No inspiral signals
were found. Assuming a spherical halo with core radius 5 kpc extending to 50
kpc containing non-spinning black holes with masses in the range 0.2--, we place an observational upper limit on the rate of PBH coalescence
of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.
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