Search

While terrestrial decomposition has been extensively researched to produce reliable methods of estimating the post-mortem interval of remains, there is limited literature documenting aquatic decomposition. Consequently, the ability to reliably estimate the post-mortem submersion interval for remains in water bodies is poor, despite markedly varying insect succession between aquatic and terrestrial decomposition This study was conducted to compare decomposition on Sus domesticus carcases in terrestrial and artificial lentic environments, aiming to provide more detailed characterization of aquatic decomposition and document the role of terrestrial organisms in the accompanying insect succession. Three trials consisting of six stillborn piglets in lentic environments and three in terrestrial environments were observed daily over a period of 12 months. Decomposition stage and morphological changes between terrestrial and lentic piglets were noted. Insects were sampled from remains and reared to adulthood for identification. Lentic decomposition was prolonged relative to terrestrial decomposition, reflecting aquatic decomposition characteristics accompanied by terrestrial insect colonization. Diptera were more prevalent on terrestrial remains, and Coleoptera in the lentic environments, with few dipteran taxa common between environments. Results show the variability of decomposition stages, characteristics and insects between terrestrial and lentic remains, and are discussed with regard to implications for aquatic forensic casework. [ABSTRACT FROM AUTHOR]

Measures the effect of axial tensile stress, applied at room-temperature, on the critical current of NbTi superconducting wire. Comparison to the effect of tensile stress applied at liquid-helium temperature; Methods for determining the stress on the NbTi from the total composite load; Multifilamentary NbTi sample characteristics.

Investigates the effect of transverse stress on the critical current of two Nb[sub3]Sn superconductors, a bronze-process conductor and an internal-tin conductor. Difference in the microstructure of the two conductors; Description of the radial orientation of the bronze-process grains; Effect of the transverse stress measured on the internal-tin conductor.

The RNA helicase p68 (DDX5) is an established co-activator of the p53 tumour suppressor that itself has a pivotal role in orchestrating the cellular response to DNA damage. Although several factors influence the biological outcome of p53 activation, the mechanisms governing the choice between cell-cycle arrest and apoptosis remain to be elucidated. In the present study, we show that, while p68 is critical for p53-mediated transactivation of the cell-cycle arrest gene p21WAF1/CIP1, it is dispensable for induction of several pro-apoptotic genes in response to DNA damage. Moreover, p68 depletion results in a striking inhibition of recruitment of p53 and RNA Pol II to the p21 promoter but not to the Bax or PUMA promoters, providing an explanation for the selective effect on p21 induction. Importantly, these findings are mirrored in a novel inducible p68 knockout mouse model in which p68 depletion results in a selective inhibition of p21 induction in several tissues. Moreover, in the bone marrow, p68 depletion results in an increased sensitivity to γ-irradiation, consistent with an increased level of apoptosis. These data highlight a novel function of p68 as a modulator of the decision between p53-mediated growth arrest and apoptosis in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Public health interventions targeting drug users can focus on changing individual risk behaviors or on changing the social and environmental contexts which facilitate individual risk taking. In this article, we focus on the latter interventions, creating a framework for understanding which structural interventions might be useful in reducing risk. We apply the framework to the example of opiate maintenance therapy in the United States to supply examples of structural barriers to maintenance therapy and describe how structural interventions can be useful in reducing these barriers. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy has been used to measure the size of the delta phase, and electrical resistivity to determine lithium concentration in the matrix, during coarsening of the delta phase. Application of the Lifshitz-Slyozov-Wagner theory of particle coarsening has enabled independent calculation of the delta-alpha interface energy gamma and the effective diffusivity Deff of lithium in aluminium during delta coarsening. For an alloy containing 7.6 at.% Li, gamma is found to be 0.045 Jm-2 and Deff at a temperature T is defined by the equation Deff (m2s-1)=1.5 - 10-6 exp (-118 400 ___ RT). Increasing the lithium concentration of the alloy to 9.8 at.% had little effect on the activation energy of delta coarsening but it reduced the value of the pre-exponential factor. [ABSTRACT FROM AUTHOR]

To measure the critical current of superconductors, a high output current supply is required. In addition to high current capability, the supply should be designed to reduce ground loop problems, respond linearly to an input control signal, and minimize output noise. A current supply with these qualifications has been constructed and tested. Although the supply was originally designed for testing conventional superconductors at high current levels, it has also been successfully used in measurements on the high-critical-temperature ceramic superconductors where the maximum current output was less than 1 A. The supply can produce 1000 A output current with a noise level of approximately 0.05 A peak-to-peak. The specifics of the current supply’s design and performance are given. [ABSTRACT FROM AUTHOR]

We assessed dust coverage on the Mars Science Laboratory Mars Hand Lens Imager (MAHLI) and Alpha Particle X-Ray Spectrometer (APXS) calibration targets from 14 MAHLI images acquired at <100 μm/pixel, between Mars Science Laboratory Curiosity rover sols 34 and 2248, in order to place constraints on dust accumulation and removal on two endmember orientations (vertical and horizontal). Dust coverage was estimated by (1) determining reflectance ranges for image pixels covered by dust; (2) using the ratio of calibrated MAHLI red band data to blue band data as a proxy for the concentration of dust on the calibration target; and (3) manually counting dust-covered pixels in representative areas of the MAHLI calibration target. The results of each method are consistent within uncertainties, but the reflectance method provided the most efficient and effective way to measure dust cover on each target. Mean and median dust coverage is ~4.7% and 3.9% for the MAHLI target, 9.4% and 8.9% for the APXS target, and 51.9% and 63.4% for the REMS UV sensor. Maximum dust coverage (during the dust storm) is 49% and 42% for the MAHLI and APXS calibration targets respectively, and 80% for the REMS UV sensor. In modeling dust accumulation and removal, the best fit for the MAHLI and APXS targets is one that assumes 2–4% dust removal per sol and 20–40% efficiency in collection, while for the REMS UV sensor, it is one that assumes near 0 removal and 7% of nominal accumulation. Results indicate that the vertically-mounted MAHLI and APXS targets accumulated less dust overall during the mission than horizontally-mounted hardware such as the REMS UV sensor; this was true even during the 2018 global dust event. In addition, while the vertical orientation did not protect the targets from dust deposition during that event, dust removal following the event was more effective on these targets than on horizontally-mounted hardware. Because conditions cannot be monitored continuously, these studies cannot fully discriminate among the potential causes of this dust removal. However, the results suggest that vertical mounting is a reasonable dust mitigation strategy for hardware for which short-term dust accumulation is not a risk factor. • Three methods give accurate estimates for martian dust coverage. • Horizontal surfaces are subject to mechanisms that deposit but rarely remove dust. • Vertical surfaces are subject to processes that deposit but also remove dust. • Vertical mounting means less dust accumulation long-term. • Such a configuration does not fully protect hardware from dust. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Tension headache may be TMJD," in the 2006 issue.

Presents a letter to the editor on the importance of muscle dysfunction in chronic head, neck and facial pain.

Presents a letter the editor in response to the article "Review of Clinical Techniques," previously published in "British Dental Journal."

Presents a letter to the editor about the need for an efficient dental waste management.

Presents a letter to the editor of "British Dental Journal" responding to the article by Holbrook, Arnadottir and Kay, "Prevention of tooth wear".

Rocky shores provide a harsh environment for marine organisms and webriefly discuss natural sources of variation in community structure before considering anthropogenic impacts in detail. We review impactscaused by (a) acute disturbances: oil spills, toxic algal blooms and(b) chronic disturbances: nutrient pollution, oil, heavy metals, pesticides, antifouling paints, collecting, trampling/habitat degradation, siltation and introduced species. Community level effects are emphasised throughout and illustrative examples are drawn from field-based case studies. Particular attention is given to the lessons learned from oil spills and the effect of chronic pollution by tributyltin ondogwhelks, the impacts of which ranged from the biochemical to community levels of organisation. Impacts are placed in a global and historical perspective and the potential for the recovery of shores under appropriate management is discussed. Finally we consider the relativemerits of the multivariate and univariate approaches to studying impacted communities and suggest priorities for future research. [ABSTRACT FROM AUTHOR]

In 2014, the Australian Government implemented the Emissions Reduction Fund to offer incentives for businesses to reduce greenhouse gas (GHG) emissions by following approved methods. Beef cattle businesses in northern Australia can participate by applying the 'reducing GHG emissions by feeding nitrates to beef cattle' methodology and the 'beef cattle herd management' methods. The nitrate (NO3) method requires that each baseline area must demonstrate a history of urea use. Projects earn Australian carbon credit units (ACCU) for reducing enteric methane emissions by substituting NO3 for urea at the same amount of fed nitrogen. NO3 must be fed in the form of a lick block because most operations do not have labour or equipment to manage daily supplementation. NO3 concentrations, after a 2-week adaptation period, must not exceed 50 g NO3/adult animal equivalent per day or 7 g NO3/kg dry matter intake per day to reduce the risk of NO3 toxicity. There is also a 'beef cattle herd management' method, approved in 2015, that covers activities that improve the herd emission intensity (emissions per unit of product sold) through change in the diet or management. The present study was conducted to compare the required ACCU or supplement prices for a 2% return on capital when feeding a low or high supplement concentration to breeding stock of either (1) urea, (2) three different forms of NO3 or (3) cottonseed meal (CSM), at N concentrations equivalent to 25 or 50 g urea/animal equivalent, to fasten steer entry to a feedlot (backgrounding), in a typical breeder herd on the coastal speargrass land types in central Queensland. Monte Carlo simulations were run using the software @risk, with probability functions used for (1) urea, NO3 and CSM prices, (2) GHG mitigation, (3) livestock prices and (4) carbon price. Increasing the weight of steers at a set turnoff month by feeding CSM was found to be the most cost-effective option, with or without including the offset income. The required ACCU prices for a 2% return on capital were an order of magnitude higher than were indicative carbon prices in 2015 for the three forms of NO3. The likely costs of participating in ERF projects would reduce the return on capital for all mitigation options. [ABSTRACT FROM AUTHOR]

Neutron flux measurements are important in fusion devices for both safety requirements and physics studies. A new system has been built for the Mega-Amp Spherical Tokamak Upgrade (MAST Upgrade) that provides neutron count, DC, and Campbell mode measurements for a 1 µs period at 1 MHz. The acquisition system uses a Red Pitaya board to sample current from two fission chambers mounted on the side of the MAST-U vessel. The system-on-chip design of the Zynq-7020 on the Red Pitaya also allows a web server implementation using Flask for data retrieval and diagnostic configuration over the MAST Upgrade network. [ABSTRACT FROM AUTHOR]

The RNA helicase p68 is a potent co-activator of p53-dependent transcription in response to DNA damage. Previous independent studies have indicated that p68 and the Δ133p53 isoforms, which modulate the function of full-length p53, are aberrantly expressed in breast cancers. Here we identify a striking inverse association of p68 and Δ133p53 expression in primary breast cancers. Consistent with these findings, small interfering RNA depletion of p68 in cell lines results in a p53-dependant increase of Δ133p53 in response to DNA damage, suggesting that increased Δ133p53 expression could result from downregulation of p68 and provide a potential mechanistic explanation for our observations in breast cancer. Δ133p53α, which has been shown to negatively regulate the function of full-length p53, reciprocally inhibits the ability of p68 to stimulate p53-dependent transcription from the p21 promoter, suggesting that Δ133p53α may be competing with p68 to regulate p53 function. This hypothesis is underscored by our observations that p68 interacts with the C-terminal domain of p53, co-immunoprecipitates 133p53α from cell extracts and interacts only with p53 molecules that are able to form tetramers. These data suggest that p68, p53 and 133p53α may form part of a complex feedback mechanism to regulate the expression of Δ133p53, with consequent modification of p53-mediated transcription, and may modulate the function of p53 in breast and other cancers that harbour wild-type p53. [ABSTRACT FROM AUTHOR]

The impact of swinging boat moorings on intertidal benthic assemblages was investigated in a small estuary on the south coast of England. Mooring buoys fixed near low water mark on a muddy shore were attached to 5 m of galvanised steel chain and had not been let for 12 months. Core samples for macro-invertebrates and sediments were taken both within and outside the chain radius of each buoy. The assemblage structure, biomass and abundance of selected bird prey species were examined at a range of scales. The study revealed variation in the impact of mooring buoys relative to control areas at two different times of sampling. Prior to the removal of buoys, the assemblage structure within areas affected by the buoys was found to be significantly different from unaffected areas. The abundance of the amphipod Corophium volutator, an important bird prey species, was significantly less in the areas affected by the buoys. In the second sampling programme (15 months after removal of buoys), the impact of extant buoys remaining in commission was not detectable. Assemblage structure in areas from which buoys had been removed was distinct from control areas which had never had buoys. The removal of mooring buoys clearly affected the assemblage, yet convergence with control areas, indicative of recovery, was not complete after 15 months. It is suggested that the effect of swinging mooring chains scraping over the mud surface may modify sediments favouring the greater prominence of larger particles such as gravel and shell fragments. The ecological impact of swinging moorings on estuarine benthic assemblages in designated protected areas is discussed in the context of other spatial and temporal disturbances. [ABSTRACT FROM AUTHOR]

The high temperature fatigue performance of two dissimilar material joints made by inertia friction welding and linear friction welding is assessed in the present study. The fatigue strength of the welded joints is found to be comparable to that of the weaker parent material for the plainsided specimens. However, the fatigue crack growth resistance within the weld zone of both material systems is found to be reduced compared to that of parent material. This effect is more pronounced for high temperature Ni alloys than for the lower temperature nickel alloy. Environmental attack is confirmed to be the controlling failure mechanism for acceleration of crack growth, but the extent to which it is observed is sensitive to local microstructure, i.e. to grain size, redistribution of the main strengthening phase γ′, and to the grain boundary carbide morphology. Such local microstructural variations are the result of welding and subsequent post-weld heat treatment procedures. [ABSTRACT FROM AUTHOR]

Much of Earth's biodiversity has the capacity to engage in dormancy, a reversible state of reduced metabolic activity. By increasing resilience to unfavourable conditions, dormancy leads to the accumulation of 'seed banks'. These reservoirs of genetic and phenotypic diversity should diminish the strength of environmental filtering and increase rates of dispersal. Although prevalent among single-celled organisms, evidence that dormancy influences patterns of microbial biogeography is lacking. We constructed geographical and environmental distance-decay relationships (DDRs) for the total (DNA) and active (RNA) portions of bacterial communities in a regional-scale 16S rRNA survey of forested ponds in Indiana, USA. As predicted, total communities harboured greater diversity and exhibited weaker DDRs than active communities. These observations were robust to random resampling and different community metrics. To evaluate the processes underlying the biogeographic patterns, we developed a platform of mechanistic models that used the geographical coordinates and environmental characteristics of our study system. Based on more than 106 simulations, our models approximated the empirical DDRs when there was strong environmental filtering along with the presence of long-lived seed banks. By contrast, the inclusion of dispersal generally decreased model performance. Together, our findings support recent theoretical predictions that seed banks can influence the biogeographic patterns of microbial communities. [ABSTRACT FROM AUTHOR]

Background:Proteomics-based approaches for biomarker discovery are promising strategies used in cancer research. We present state-of-art label-free quantitative proteomics method to assess proteome of renal cell carcinoma (RCC) compared with noncancer renal tissues.Methods:Fresh frozen tissue samples from eight primary RCC lesions and autologous adjacent normal renal tissues were obtained from surgically resected tumour-bearing kidneys. Proteins were extracted by complete solubilisation of tissues using filter-aided sample preparation (FASP) method. Trypsin digested proteins were analysed using quantitative label-free proteomics approach followed by data interpretation and pathways analysis.Results:A total of 1761 proteins were identified and quantified with high confidence (MASCOT ion score threshold of 35 and P-value <0.05). Of these, 596 proteins were identified as differentially expressed between cancer and noncancer tissues. Two upregulated proteins in tumour samples (adipose differentiation-related protein and Coronin 1A) were further validated by immunohistochemistry. Pathway analysis using IPA, KOBAS 2.0, DAVID functional annotation and FLink tools showed enrichment of many cancer-related biological processes and pathways such as oxidative phosphorylation, glycolysis and amino acid synthetic pathways.Conclusions:Our study identified a number of differentially expressed proteins and pathways using label-free proteomics approach in RCC compared with normal tissue samples. Two proteins validated in this study are the focus of on-going research in a large cohort of patients. [ABSTRACT FROM AUTHOR]

Background We evaluated the efficacy and safety of ganitumab (a mAb antagonist of insulin-like growth factor 1 receptor) or conatumumab (a mAb agonist of human death receptor 5) combined with gemcitabine in a randomized phase 2 trial in patients with metastatic pancreatic cancer. Patients and methods Patients with a previously untreated metastatic pancreatic adenocarcinoma and an Eastern Cooperative Oncology Group (ECOG) performance status ≤1 were randomized 1 : 1 : 1 to i.v. gemcitabine 1000 mg/m2 (days 1, 8, and 15 of each 28-day cycle) combined with open-label ganitumab (12 mg/kg every 2 weeks [Q2W]), double-blind conatumumab (10 mg/kg Q2W), or double-blind placebo Q2W. The primary end point was 6-month survival rate. Results In total, 125 patients were randomized. The 6-month survival rates were 57% (95% CI 41–70) in the ganitumab arm, 59% (42–73) in the conatumumab arm, and 50% (33–64) in the placebo arm. The grade ≥3 adverse events in the ganitumab, conatumumab, and placebo arms, respectively, included neutropenia (18/22/13%), thrombocytopenia (15/17/8%), fatigue (13/12/5%), alanine aminotransferase increase (15/5/8%), and hyperglycemia (18/2/3%). Conclusions Ganitumab combined with gemcitabine had tolerable toxicity and showed trends toward an improved 6-month survival rate and overall survival. Additional investigation into this combination is warranted. Conatumumab combined with gemcitabine showed some evidence of activity as assessed by the 6-month survival rate. [ABSTRACT FROM AUTHOR]

Background:Observations that diabetics treated with biguanide drugs have a reduced risk of developing cancer have prompted an enthusiasm for these agents as anti-cancer therapies. We sought to determine the efficacy of the biguanide phenformin in the chemoprophylaxis and in the treatment of oestrogen receptor (ER)-positive MCF7 and receptor triple-negative MDAMB231 xenografts in immunocompromised mice. We also compared the efficacy of phenformin and metformin in the treatment of MDAMB231.Methods:Immunocompromised mice were divided into groups: (1) phenformin administered for 2 weeks prior to cell injection; (2) established tumours treated with phenformin; (3) established tumours treated with metformin (only for MDAMB231 tumours); (4) untreated controls. Post-treatment tumours, liver and spleen were harvested for further analysis.Results:Phenformin significantly inhibited both the development and growth of MCF7 and MDAMB231 tumours, and for MDAMB231 at greater efficacy than metformin without murine toxicity. The number of mitotic figures was significantly fewer in xenografts treated with phenformin compared with controls. Results suggested that the mechanism of action of phenformin in vivo is consistent with AMPK activation.Conclusion:Phenformin has clinical potential as an antineoplastic agent and should be considered for clinical trials both in ER-positive and triple-negative breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: Microstructure in the weld line (WL) zone produced by inertial friction welding has been studied for a series of RR1000–RR1000 welds using transmission electron and scanning electron microscopy. A fully recrystallised fine grain structure was found to form throughout the WL zone, characterized by straight and smooth grain boundaries, high energy status and modified grain boundary chemistry due to very fast cooling after welding. Very fine γ′ particles with unimodal size distribution were reprecipitated in the WL zone. The fine γ′ particles are spherical in shape, high in number density and characterized by an imbalanced chemistry, containing less Al, Ti, Ni, Ta γ′-forming elements but more Cr, Co, Mo γ-forming elements than all types of parent γ′ particles. As a result, a hard and strong WL zone was produced by the inertial friction welding. [Copyright &y& Elsevier]

The DEAD-box RNA helicases p68 (DDX5) and p72 (DDX17) have been shown to act as transcriptional co-activators for a diverse range of transcription factors, including oestrogen receptor-α (ERα). Here, we show that, although both proteins interact with and co-activate ERα in reporter gene assays, small interfering RNA-mediated knockdown of p72, but not p68, results in a significant inhibition of oestrogen-dependent transcription of endogenous ERα-responsive genes and oestrogen-dependent growth of MCF-7 and ZR75-1 breast cancer cells. Furthermore, immunohistochemical staining of ERα-positive primary breast cancers for p68 and p72 indicate that p72 expression is associated with an increased period of relapse-free and overall survival (P=0.006 and 0.016, respectively), as well as being inversely associated with Her2 expression (P=0.008). Conversely, p68 shows no association with relapse-free period, or overall survival, but it is associated with an increased expression of Her2 (P=0.001), AIB-1 (P<0.001) and higher tumour grade (P=0.044). Our data thus highlight a crucial role for p72 in ERα co-activation and oestrogen-dependent cell growth and provide evidence in support of distinct but important roles for both p68 and p72 in regulating ERα activity in breast cancer. [ABSTRACT FROM AUTHOR]

In this paper, the levels of residual stress in the vicinity of linear friction welds in Ti 6Al-4V (Ti-64), a conventional α-β titanium alloy, and Ti-6Al-2Sn-4Zr-2Mo (Ti-6242), a near α titanium alloy with higher temperature capability, are mapped and contrasted. The alloys have significantly different high temperature properties and the aim of this work was to investigate how this might affect their propensity to accumulate weld residual stresses and their response to post-weld heat treatment. Measurements are reported using high energy synchrotron X-ray diffraction and the results are compared to those made destructively using the contour method. The strain free lattice plane do variation across the weld has been evaluated using the biaxial sin²ψ technique with laboratory X-rays. It was found that failure to account for the do variation across the weld line would have led to large errors in the peak tensile stresses. Contour method measurements show fairly good correlation with the diffraction results, although the stresses are underestimated. Possible reasons for the discrepancy are discussed. The peak tensile residual stresses introduced by the welding process were found to be greater for Ti-6242 (~750 MPa) than for Ti-64 (~650 MPa). Consistent with the higher temperature capability of the alloy, higher temperature post-weld heat treatments have been found to be necessary to relieve the stresses in the near α titanium alloy compared to the α+β titanium alloy. [ABSTRACT FROM AUTHOR]

Abstract: Effects of crystal orientation on weldability and microstructural evolution occurring during linear friction joining of single crystal nickel-base superalloy to polycrystalline nickel-base superalloy were studied. Electron microscopy was used to characterize deformation and microstructural development. Changes in friction coefficient with changes in crystal orientation were observed and correlated to the metallurgical adhesion. These changes were explained by taking into consideration the single crystal deformation mechanisms. It was concluded that the orientation of the single crystal with reference to the principal axes of the pressure force is of utmost importance during linear friction welding (LFW) due to changes in orientation of the primary slip system in the fcc-based single crystal lattice. [Copyright &y& Elsevier]

Study design:Prospective, observational cohort study.Objectives:This paper describes the rationale and methodology for the Study of Health and Activity in People with Spinal Cord Injury (SHAPE SCI). The study aims to (1) describe physical activity levels of people with different injury levels and completeness, (2) examine the relationship between physical activity, risk and/or presence of secondary health complications and risk of chronic disease, and (3) identify determinants of physical activity in the SCI population.Setting:Ontario, Canada.Methods:Seven hundred and twenty men and women who have incurred a traumatic SCI complete self-report measures of physical activity, physical activity determinants, secondary health problems and subjective well-being during a telephone interview. A representative subsample (n=81) participate in chronic disease risk factor testing for obesity, insulin resistance and coronary heart disease. Measures are taken at baseline, 6 and 18 months.Conclusion:SHAPE SCI will provide much-needed epidemiological information on physical activity patterns, determinants and health in people with SCI. This information will provide a foundation for the establishment of evidence-based physical activity guidelines and interventions tailored to the SCI community.Spinal Cord (2008) 46, 216–221; doi:10.1038/sj.sc.3102103; published online 24 July 2007 [ABSTRACT FROM AUTHOR]

Abstract: Microstructure and microtexture development in as-welded and post weld heat treated (PWHT) lab-scale (LS) and full-scale (FS) Ti–6Al–4V linear friction welds have been characterized using scanning electron microscopy and electron back-scatter diffraction (EBSD). The full-scale specimens exhibited a plastically affected zone (PAZ) about twice the size compared to lab-scale test welds. At the weld line a region of very fine martensitically formed microstructure was observed in both the LS and FS friction welds. EBSD texture scans across the weld line revealed a sharp texture variation in the PAZ. At the weld line a strong transverse texture for the as-welded and PWHTed condition was observed in both welds. Whereas the lab-scale linear friction welds displayed a dramatic change from almost random to strong transverse texture in the PAZ, the full-scale linear friction welds exhibited transverse texture at the weld line, followed by dispersed bands of transverse and type rolling texture in the PAZ region. The observed difference in LS and FS weld region textures is attributed to a difference in the variant selections during β→α transformation. [Copyright &y& Elsevier]

Residual stresses in linear friction welded (LFW) IMI550 have been determined by means of high energy synchrotron X-ray diffraction. Specimens were studied in the as-welded, and three different post weld heat treated conditions. Mid-thickness-mid-width line scans were recorded across the weld Une in the three principal directions of the welds. For calculating the nominal residual strain the "stress-free" lattice spacing was taken from far field measurements. The separation of a chemical induced and strain induced shift of the reflection was carried out by determining the variation of the d-spacing across the weld line. This was done on thin slices cut from the centre region of a LFW sample using the biaxial sin²ψ-technique on a collimated laboratory X-ray source. Results show large tensile stresses close to the weld line for the as-welded sample and the sample post weld heat treated at the aging temperature typical of IMI550. Moderate residual stresses were observed after increasing the post weld heat treatment (PWHT) temperature by 100 or 150°C. All conditions displayed a significant hydrostatic tensile stress field component, which is generally difficult to relieve. This work demonstrates that residual strain measurements have to be carried out using a high spatial resolution in order to resolve the sharp strain gradients apparent in LFW Titanium alloys. [ABSTRACT FROM AUTHOR]

Residual stresses in linear friction welded (LFW) 1M1550 have been determined by means of high energy synchrotron X-ray diffraction. Specimens were studied in the as-welded, and three different post weld heat treated conditions. Mid-thickness-mid-width line scans were recorded across the weld line in the three principal directions of the welds. For calculating the nominal residual strain the "stress-free" lattice spacing was taken from far field measurements. The separation of a chemical induced and strain induced shift of the reflection was carried out by determining the variation of the d-spacing across the weld line. This was done on thin slices cut from the centre region of a LFW sample using the biaxial sin²ψ-technique on a collimated laboratory X-ray source. Results show large tensile stresses close to the weld line for the as-welded sample and the sample post weld heat treated at the aging temperature typical of IMI550. Moderate residual stresses were observed after increasing the post weld heat treatment (PWHT) temperature by 100 or 150°C. All conditions displayed a significant hydrostatic tensile stress field component, which is generally difficult to relieve. This work demonstrates that residual strain measurements have to be carried out using a high spatial resolution in order to resolve the sharp strain gradients apparent in LFW Titanium alloys. [ABSTRACT FROM AUTHOR]

Recovery of marine ecosystems from pollution has tended to receive less attention than the study of new or continuing impacts, but such studies are important in charting recovery from acute incidents and following legislation to deal with chronic contamination. Recovery is inevitably a long-term process, and where such studies have been made they are often too short-lived. Interest quickly wanes following an acute incident and governmental bodies rapidly switch to new legislative priorities for chronic inputs. We review three case studies: recovery of dogwhelk populations after local extinction by tributyl tin leachates from antifouling paints; recovery of rocky shore communities from oil spills; and recovery of estuarine ecosystems from industrial and urban development. We then make some generalisations about recovery processes before making a plea for long-term studies of polluted areas. [Copyright &y& Elsevier]

Ni-based superalloys IN718 and IN713LC have been joined through linear friction welding (LFW) in this study. The variation of microstructure across the weld line developed during linear friction welding and after post weld heat-treatment (PWHT) has been investigated. Their effects on microhardness have also been studied. A clean weld region which is free of micro-porosity, micro-cracking and oxides, was achieved. Dynamic recrystallisation (full and partial) occurred on both sides of the weld, which produced much finer grains in the recrystallised zone. Dissolution of 'parent' γʹ/γʹʹ, towards the weld line was observed on each side of the weld. However, reprecipitation of γ′ was only found in the as-welded IN713LC. All these were found to have a huge impact on the hardness profile. A softer heat affected zone (HAZ) was found in the IN718 side with the lowest hardness value achieved at an axial position 0.6 mm from the weld line. The increased dissolution of γ'/γ'' towards the weld line resulted in decreasing hardness towards the weld line. However, the formation of refined grains closer to the weld line increased the hardness towards the weld line from axial position 0.6 mm. In contrast, a harder HAZ was found in the IN713LC side, which resulted from the formation of finer reprecipitated γ′ and recrystallised grains. PWHT brought about reprecipitation and/or further reprecipitation of γʹ/γʹʹ in the IN718 and IN713LC HAZs, resulting in stronger HAZs. [ABSTRACT FROM AUTHOR]

Discusses issues concerning dentistry. Oral health promotion; Use of clinical gloves impregnated with herbal substance aloe vera; Professional responsibility.

Presents letters to the editor pertaining to articles published in the 'British Dental Journal.' Role of removable appliances in contemporary orthodontics; Use of gothic arch tracing approach for dental occlusion; Recognition of orthodontists as specialists.

Develops a flexible high-current lead for use at cryogenic temperatures and in high-magnetic fields using high purity aluminum. Advantages of readily available high purity aluminum over copper; Practical issues encountered in the design and fabrication of flexible leads.