Observation of inverse Compton emission from a long γ-ray burst.

Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission1,2. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands1-6. The afterglow emission is generally well explained as synchrotron radiation emitted by electrons accelerated by the external shock7-9. Recently, intense long-lasting emission between 0.2 and 1 teraelectronvolts was observed from GRB 190114C10,11. Here we report multi-frequency observations of GRB 190114C, and study the evolution in time of the GRB emission across 17 orders of magnitude in energy, from 5 × 10-6 to 1012 electronvolts. We find that the broadband spectral energy distribution is double-peaked, with the teraelectronvolt emission constituting a distinct spectral component with power comparable to the synchrotron component. This component is associated with the afterglow and is satisfactorily explained by inverse Compton up-scattering of synchrotron photons by high-energy electrons. We find that the conditions required to account for the observed teraelectronvolt component are typical for GRBs, supporting the possibility that inverse Compton emission is commonly produced in GRBs.

Investigating the appropriateness of physician-ordered diagnostic computed tomography for patient management in a rural hospital in New South Wales, Australia.

AIM: To examine the performance of "appropriate" versus "inappropriate" computed tomography (CT) and to examine whether physicians who practise in a rural hospital in NSW Australia, achieved imaging appropriateness in their ordering of diagnostic CT examinations. MATERIALS AND METHODS: An audit of the electronic medical records of medical ward inpatients (during the 2016/2017 financial year) was carried out. De-identified data were extracted for all patients who had undergone diagnostic CT while on admission. Using the SPSS analytical software, chi-square tests for independence were conducted to check for difference between appropriate and inappropriate CT imaging. RESULTS: Of all the CT procedures, 92% were found to be appropriate. Appropriate CT confirmed the provisional diagnosis in more instances than inappropriate CT (132 versus three). This observed difference was significant with a small size effect (chi-squared [1, n=362]=8.58, p=0.003, φ=0.16). Similarly, appropriate CT significantly facilitated a change in the proposed direction of care (140 versus 40) (chi-squared [1, n=362]=7.75, p=0.005, φ=0.16). In addition, appropriate CT which confirmed diagnosis, resulted in a change in the proposed direction of care as opposed to inappropriate CT (115 versus one; chi-squared [1, n=362]=8.11, p=0.004, Cramer's V=0.24). CONCLUSION: Specialist physicians who practise in a rural hospital setting achieved CT appropriateness. Appropriate CT is beneficial to patient care. Adhering to recommended imaging guidelines is essential for achieving imaging appropriateness.

Who contributes to the occupational health evidence base?

BACKGROUND: Whilst there has been recognition of the need to strengthen the evidence base for occupational health in the UK, it is not clear how much different groups contribute to the emerging research. AIMS: To establish the research contribution from different types of organization and how this has changed. METHODS: All original research papers published in Occupational Medicine in the 5-year periods July 1996 to June 2001 and July 2006 to June 2011 were reviewed. The lead authors' affiliations were classified in the most relevant sector. RESULTS: The number of research papers published by authors affiliated to UK organizations was greater in the past 5 years than in a similar period a decade ago. The increase is wholly explained by a large increase in papers from universities. About one-fifth of all papers published in Occupational Medicine from UK sources had a principal affiliation with the National Health Service (NHS). The number of papers affiliated to large private sector companies reduced from 14 to 2. No papers arose from the work of established specialists employed by the large commercial providers of occupational health services. CONCLUSIONS: Services provided in the NHS and other public sector organizations are important contributors of new evidence in occupational health. Commissioners of public sector services should take account of the importance of this to the research and innovation in occupational health.

Measuring implementation of evidence-based guidance on promoting workers' health.

BACKGROUND: The National Health Service (NHS) employs 1.4 million people in England. In health care, improved workforce health has been associated with improved outcomes for patients. The UK's National Institute for Health and Clinical Excellence (NICE) has produced evidence-based guidance on improving workers' health. However, the extent of implementation of evidence-based guidance has not previously been measured. AIMS: To measure progress with implementation of NICE guidance on workplace health and identify opportunities to improve this. METHODS: All NHS organizations in England were invited to participate in an audit of implementation of NICE guidance. A web-based tool was developed to collect information on the extent to which each organization had implemented NICE guidance addressing health promotion in the workplace. RESULTS: The number of organizations that participated was 282. These employed a total of 868 979 workers. Organizations were more likely to involve staff in planning and designing an organizational approach to each topic where health and well-being was a regular board agenda item. Those with an overarching strategy were more likely to have staff health and well-being as a regular board agenda item (P < 0.05) and more likely to have specific policies for obesity, physical activity and promoting mental well-being (all P <0.01). CONCLUSIONS: Implementation of NICE guidance on health at work is incomplete across the NHS in England. Implementation was more complete where boards were leading health and well-being plans and the workforce were actively involved. There is scope to improve the implementation of evidence-based guidance to improve workers' health.

Complete Genome Sequence of Paraclostridium bifermentans DSM 14991.

The complete genome sequence of Paraclostridium bifermentans was obtained by assembly of Illumina and Oxford Nanopore (ONT) reads. The sequence will enable study into the organism's ability to biohydrogenate unsaturated acyl chains in the transformation of C20 polyunsaturated fatty acids (PUFAs) into the corresponding bioactive non-methylene-interrupted fatty acids (NMIFAs).

A gamma-ray burst with a high-energy spectral component inconsistent with the synchrotron shock model.

Gamma-ray bursts are among the most powerful events in nature. These events release most of their energy as photons with energies in the range from 30 keV to a few MeV, with a smaller fraction of the energy radiated in radio, optical, and soft X-ray afterglows. The data are in general agreement with a relativistic shock model, where the prompt and afterglow emissions correspond to synchrotron radiation from shock-accelerated electrons. Here we report an observation of a high-energy (multi-MeV) spectral component in the burst of 17 October 1994 that is distinct from the previously observed lower-energy gamma-ray component. The flux of the high-energy component decays more slowly and its fluence is greater than the lower-energy component; it is described by a power law of differential photon number index approximately -1 up to about 200 MeV. This observation is difficult to explain with the standard synchrotron shock model, suggesting the presence of new phenomena such as a different non-thermal electron process, or the interaction of relativistic protons with photons at the source.

Amino acid geochronology of the type Cromerian of West Runton, Norfolk, UK.

Aminostratigraphic studies of continental deposits in the UK have hitherto relied almost exclusively on data from the aragonitic shells of non-marine molluscs for dating Pleistocene sequences. This is usually based on the d/l value of a single amino acid, d-alloisoleucine/l-isoleucine (A/I), in the total shell proteins. Two genera of freshwater gastropods (Valvata and Bithynia) are used to explore the value of using multiple amino acids from the intra-crystalline fraction, which should be more protected from the effects of diagenesis than the inter-crystalline component. Results are compared from both the aragonitic shells and opercula composed of calcite, a more stable form of calcium carbonate. In order to put the amino acid data from the West Runton Freshwater Bed into perspective, statistical analyses are used to compare them with results from the Hoxnian (MIS 11) site at Clacton-on-Sea, Essex. Twelve protein decomposition indicators revealed that the results from the shells were not as clear-cut as those from the opercula. Five indicators from the Valvata shell suggest that West Runton is older than Clacton (at a 95% significance level), but two actually suggested a younger age. Seven indicators show that the Bithynia shells from West Runton are older than congeneric shells from Clacton. In marked contrast, all 12 indicators isolated from the opercula demonstrate that West Runton is significantly older than Clacton. The data are also compared with results from Waverley Wood, an important archaeological site in the English Midlands falling within the 'Cromerian Complex'. Contrary to earlier interpretations, the new amino acid data from Bithynia opercula indicate that West Runton is older than Waverley Wood, a relationship now consistent with the available biostratigraphy.

Systematic review and narrative synthesis of surgeons' perception of postoperative outcomes and risk.

BACKGROUND: The accuracy with which surgeons can predict outcomes following surgery has not been explored in a systematic way. The aim of this review was to determine how accurately a surgeon's 'gut feeling' or perception of risk correlates with patient outcomes and available risk scoring systems. METHODS: A systematic review was undertaken in accordance with PRISMA guidelines. A narrative synthesis was performed in accordance with the Guidance on the Conduct of Narrative Synthesis In Systematic Reviews. Studies comparing surgeons' preoperative or postoperative assessment of patient outcomes were included. Studies that made comparisons with risk scoring tools were also included. Outcomes evaluated were postoperative mortality, general and operation-specific morbidity and long-term outcomes. RESULTS: Twenty-seven studies comprising 20 898 patients undergoing general, gastrointestinal, cardiothoracic, orthopaedic, vascular, urology, endocrine and neurosurgical operations were included. Surgeons consistently overpredicted mortality rates and were outperformed by existing risk scoring tools in six of seven studies comparing area under receiver operating characteristic (ROC) curves (AUC). Surgeons' prediction of general morbidity was good, and was equivalent to, or better than, pre-existing risk prediction models. Long-term outcomes were poorly predicted by surgeons, with AUC values ranging from 0·51 to 0·75. Four of five studies found postoperative risk estimates to be more accurate than those made before surgery. CONCLUSION: Surgeons consistently overestimate mortality risk and are outperformed by pre-existing tools; prediction of longer-term outcomes is also poor. Surgeons should consider the use of risk prediction tools when available to inform clinical decision-making.

ANTECEDENTES: La precisión con la cual los cirujanos pueden predecir los resultados de la cirugía no se ha estudiado de forma sistemática. El objetivo de esta revisión fue determinar con qué precisión la intuición de un cirujano o su percepción del riesgo se correlacionaba con los resultados del paciente y con los sistemas de puntuación del riesgo disponibles. MÉTODOS: Se efectuó una revisión sistemática siguiendo las directrices PRISMA. Se realizó una síntesis narrativa de acuerdo con la guía para la realización de síntesis narrativas en revisiones sistemáticas. Se incluyeron los estudios que comparaban las evaluaciones preoperatorias o postoperatorias de los cirujanos respecto a los resultados de los pacientes. También se incluyeron aquellos estudios en los que se hacían comparaciones con herramientas de puntuación de riesgo. Se evaluaron la mortalidad postoperatoria, la morbilidad global y la morbilidad específica de las intervenciones, y los resultados a largo plazo. RESULTADOS: Se incluyeron 27 estudios con 20.898 pacientes en los que se realizaron procedimientos de cirugía general, digestiva, cardiotorácica, ortopédica, vascular, urológica, endocrina y neurocirugía. Los cirujanos predijeron consistentemente mayores tasas de mortalidad, siendo superados en precisión por los sistemas de estimación del riesgo existentes en seis de los siete estudios que utilizaron el área bajo la curva (area under curve, AUC) operativa del receptor. La predicción de la morbilidad general por parte de los cirujanos fue buena y era equivalente, incluso mejor, que los modelos de predicción de riesgos preexistentes. La capacidad de los cirujanos para predecir los resultados a largo plazo fue pobre, con una AUC que oscilaba entre 0,51 y 0,75. Cuatro de cinco estudios encontraron que las estimaciones de riesgo postoperatorias fueron más precisas que las realizadas preoperatoriamente. CONCLUSIÓN: Los cirujanos sobrestiman consistentemente el riesgo de mortalidad, siendo superados en precisión por las herramientas preexistentes. La predicción de resultados a largo plazo también es muy pobre. Los cirujanos deberían considerar el uso de herramientas de predicción de riesgo cuando estén disponibles para informar en el proceso de decisión clínica.

Limits on the spin-dependent WIMP-nucleon cross sections from the first science run of the ZEPLIN-III experiment.

We present new experimental constraints on the WIMP-nucleon spin-dependent elastic cross sections using data from the first science run of ZEPLIN-III, a two-phase xenon experiment searching for galactic dark matter weakly interacting massive particles based at the Boulby mine. Analysis of approximately 450 kg x days fiducial exposure allow us to place a 90%-confidence upper limit on the pure WIMP-neutron cross section of sigma(n)=1.9x10(-2) pb at 55 GeV/c(2) WIMP mass. Recent calculations of the nuclear spin structure based on the Bonn charge-dependent nucleon-nucleon potential were used for the odd-neutron isotopes 129Xe and 131Xe. These indicate that the sensitivity of xenon targets to the spin-dependent WIMP-proton interaction could be much lower than implied by previous calculations, whereas the WIMP-neutron sensitivity is impaired only by a factor of approximately 2.

Testing the aminostratigraphy of fluvial archives: the evidence from intra-crystalline proteins within freshwater shells.

Until recently few studies of amino acid racemization of fossil bivalves and gastropods collected from river terrace deposits in Europe were based on the analysis of the intra-crystalline fraction. Instead they were based on the epimerization (racemization) of a single amino acid, isoleucine, and its inter-conversion to alloisoleucine. This paper presents data from the analysis of the intra-crystalline fraction of the shells, using a preparation technique of sample bleaching to remove the leachable matrix, thus leaving a component that exhibits closed-system behaviour. Reverse-phase HPLC separation with fluorescence detection allows the interpretation of four amino acids in detail: aspartic acid, glutamic acid, alanine and valine. The intra-crystalline fraction offers greater potential for improved resolution, especially when combined with the analysis of multiple amino acid d/l values, which racemize at different rates. This is explored using three species of freshwater gastropods (Bithynia tentaculata and troschelii, Valvata piscinalis) and the bivalve Corbicula. Sites of different ages within the Lower Thames river terrace sequence are used as a stratigraphical framework, with samples from other southern UK sites providing supplementary evidence. The results indicate better resolution using the intra-crystalline fraction over that obtained using unbleached shells, with differentiation possible at sites of up to MIS 7 age. However, for older sites, although values are always higher, the separation is less successful. A species effect has been identified between the gastropod shells. Despite the analysis of intra-crystalline protein, amino acid data from Corbicula remain problematical. Preliminary data on the opercula from Bithynia indicate that better resolution is possible, particularly at older sites.

New and future diabetes therapies: are they safe during pregnancy?

Diabetes in pregnancy, whether the woman had diabetes prior to becoming pregnant or developed gestational diabetes, is associated with many complications and risks. In the first trimester, organogenesis can be disrupted by complications due to poor control of the mother's diabetes, leading to fetal malformations or perinatal mortality. Problems with glucose control in the remainder of the pregnancy can also have consequences for the child. These include macrosomia, shoulder dystocia, pre-eclampsia, hypoglycemia and an increased risk for obesity and diabetes in the future. Therefore, aggressive and prompt treatment of the high blood sugar levels, which cause these complications, is necessary. This review looks at the current treatments for pregnancies complicated by diabetes and evaluates the place of new and possible future treatments including diet, exercise, insulin, insulin analogs and oral and inhaled agents.

The first pulse of the extremely bright GRB 130427A: a test lab for synchrotron shocks.

Gamma-ray burst (GRB) 130427A is one of the most energetic GRBs ever observed. The initial pulse up to 2.5 seconds is possibly the brightest well-isolated pulse observed to date. A fine time resolution spectral analysis shows power-law decays of the peak energy from the onset of the pulse, consistent with models of internal synchrotron shock pulses. However, a strongly correlated power-law behavior is observed between the luminosity and the spectral peak energy that is inconsistent with curvature effects arising in the relativistic outflow. It is difficult for any of the existing models to account for all of the observed spectral and temporal behaviors simultaneously.

Prevention of laboratory animal allergy.

BACKGROUND: Laboratory animal allergy (or LAA) is an important threat to the occupational health of those who work with rats, mice and other species. AIM: This review examines the risk factors for LAA and the effectiveness of control measures. METHODS: A literature review was performed. RESULTS: An extensive literature was identified regarding LAA and the use of control measures. The contribution that these measures can make to the overall effectiveness of an occupational health and safety programme is discussed in the context of the literature currently available. CONCLUSION: The incidence of this disease can be reduced by effective, integrated health risk management, with the conscientious use of engineering, procedural and personal control measures.

Twelve generations of marginal protein deficiency.

1. Colonies of rats have been maintained for twleve generations on diets adequate (dietary protein energy: total metabolizable energy (NDp: E) 0-1) or marginally deficient in protein (NDp: E 0-068). 2. In the malnourished colony, the proportion of "small-for-gestational-age" offspring was ten times as high as amongst the well-nourished colony, growth was slow, sexual maturation delayed, especially in the females, and, when adult, both sexes were significantly lighter and shorter than adults of the well-nourished colony. Organs, other than the eye, weighed less than those of well-nourished "age" controls, but when expressed relative to body-weight, the brain, pituitary, thyroid, adrenals, testes, thymus and eyes were larger, the pancreas unchanged and the kidneys smaller than those of the well-nourished "age" controls. The relative weight of the liver showed little change, being slightly increased in the males and, like the ovaries, slightly reduced in the females. On a body-weight basis, the brains were about 50 percent heavier than normal, but in absolute terms were 5-5-5 percent lighter than those of the well-nourished animals, the cerebellum (10-5 percent lighter in males and 12-9 percent lighter in females) being more severely affected than the cerebrum (4 percent lighter). 3. The young malnourished rats showed increased exploratory activity, transient head tremors and an increased sensitivity to noises, the latter being long-lasting if not permanent. When adult, they showed marked differences in behaviour and learning patterns and it was difficult to attract and hold their attention. In situations demanding a choice the animals were very excited, emitted loud squeals and tried to escape from what was clearly a stressful situation. However, a casual examination of the malnourished adults revealed a rather small, badly groomed, excitable rat without gross abnormalities. 4. The findings are discussed in relation to changes found in malnourished human communities.

The effect of rehabilitation at different stages of development of rats marginally malnourished for ten to twelve generations.

1. Rats which have been maintained for ten to twelve generations on diets of low protein value were rehabilitated in utero (group P), from birth (group F) and from 4 weeks of age (group W). 2. Group W showed little change in physique, behaviour or learning, indicating that for recovery to be effective refeeding must begin earlier. 3. Group F just failed to attain full physical recovery (90%) whereas group P overgrew by 18.6% in weight and 8.5% in length. 4. In a test designed to evaluate learning ability rehabilitated rats of groups P and F were significantly less successful than normal rats, but more successful than rats of group W or rats of the original undernourished colony. 5. Rehabilitation for a further two generations in groups F and P corrected any residual physical and behavioural defects but produced no further improvement on the Lashley (1938) jumping platform.

Plasma FSH, LH, the positive feedback of oestrogen, ovulation and luteal function in the ewe given bromocriptine to suppress prolactin during seasonal anoestrus.

The effects of pharmacological reduction of the high plasma prolactin concentration typical of seasonal anoestrus in sheep were assessed with respect to positive feedback of oestrogen on LH release, ovulation, and progesterone secretion. Treatment of 16 Scottish Blackface ewes with 1 mg bromocriptine, i.m. twice daily for 12 days, reduced prolactin concentrations in peripheral plasma from 64 +/- 10 ng/ml before treatment to < 4 ng/ml. This treatment had no effect on the proportion of ewes discharging LH and FSH in response to 12.5 microgram oestradiol benzoate (3/8 before compared with 5/16 during treatment) or the proportion of ewes ovulating in response to oestrogen treatment. Plasma progesterone concentrations remained low even in ovulating ewes. It is concluded that treatment with bromocriptine alone is unlikely to restore oestrous cycles to ewes in seasonal anoestrus.

Control of gonadotrophin release in Scottish Blackface and Finnish Landrace ewes during seasonal anoestrus.

The patterns of LH and FSH secretion were measured in 4 experimental groups of Finnish Landrace and Scottish Blackface ewes: long-term (18 months) ovariectomized ewes (Group 1), long-term ovariectomized ewes with an oestradiol implant, which has been shown to produce peripheral levels of approximately 5 pg/ml (Group 2), long-term ovariectomized ewes with an oestradiol implant for 18 months which was subsequently removed (surgery on Day 0) (Group 3) and short-term ovariectomized ewes (surgery on Day 0) (Group 4). LH and FSH concentrations were monitored in all groups at approximately weekly intervals, before and after Day 0. Finnish Landrace ewes in Groups 1, 2 and 3 had significantly higher mean FSH concentrations than did Scottish Blackface ewes (P less than 0.01). FSH and LH concentrations increased significantly in Groups 3 and 4, but values in Group 4 were significantly lower (P less than 0.01) than those in Group 1 ewes even up to 30 days after ovariectomy. In Group 3, LH concentrations increased to levels similar to those in Group 1. The pattern of LH release was, however, significantly different, with a lower LH pulse frequency (P less than 0.05), but higher pulse amplitude (P less than 0.05). This difference was maintained at least until 28 days after implant removal. We suggest that removal of negative feedback by ovariectomy demonstrates an underlying breed difference in the pattern of FSH secretion and that ovarian factors other than oestradiol are also involved in the negative-feedback control of hypothalamic/pituitary gland function. Furthermore, negative-feedback effects can be maintained for long periods, at least 28 days, after ovariectomy or oestradiol implant removal.

5,000 year-old spermatozoa in quaternary Ostracoda (Crustacea).

Fossil spermatozoa are recorded for the first time in freshwater ostracods (small bivalved crustaceans) from Holocene sediments at sites in the United Kingdom and Germany. Exceptional conditions at these sites have resulted in the preservation of chitinous "soft parts", including limbs, the remains of Zenker's Organs (sperm pumps that are part of the male reproductive apparatus in cypridoidean ostracods) and spermatozoa from eight different species. Comparisons are made with spermatozoa from living ostracods and the implications of these discoveries for evolutionary studies of reproductive modes are discussed.