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Multiwavelength studies indicate that nuclear activity and bulge properties are closely related, but the details remain unclear. To study this further, we combine $Hubble~Space~Telescope$ bulge structural and photometric properties with 1.5 GHz, $e$-MERLIN nuclear radio continuum data from the LeMMINGs survey for a large sample of 173 `active' galaxies (LINERs and Seyferts) and `inactive' galaxies (H IIs and absorption line galaxies, ALGs). Dividing our sample into active and inactive, they define distinct (radio core luminosity)$-$(bulge mass), L_R,core-M_*,bulge, relations, with a mass turnover at M_*, bulge ~ 10^(9.8 +- 0.3) M_sun (supermassive black hole mass M_BH ~ 10^(6.8 +- 0.3) M_sun), which marks the transition from AGN-dominated nuclear radio emission in more massive bulges to that mainly driven by stellar processes in low-mass bulges. None of our 10/173 bulgeless galaxies host an AGN. The AGN fraction increases with increasing M_*, bulge such that f_optical_AGN $\propto$ M_*,bulge^(0.24 +- 0.06) and f_radio_AGN $\propto$ M_*,bulge^(0.24 +- 0.05). Between M_*,bulge ~ 10^8.5 and 10^11.3 M_sun, f_optical_AGN steadily rises from 15 +- 4 to 80 +- 5 per cent. We find that at fixed bulge mass, the radio loudness, nuclear radio activity and the (optical and radio) AGN fraction exhibit no dependence on environment. Radio-loud hosts preferentially possess an early-type morphology than radio-quiet hosts, the two types are however indistinguishable in terms of bulge S\'ersic index and ellipticity, while results on the bulge inner logarithmic profile slope are inconclusive. We finally discuss the importance of bulge mass in determining the AGN triggering processes, including potential implications for the nuclear radio emission in nearby galaxies., Comment: 27 pages, 15 figures, 4 tables, accepted for publication in MNRAS

We present analysis of comprehensive radio observations of the black hole V404 Cyg during its 2015 outburst. These data represent the best ever coverage of jet production and particle acceleration from any black hole. We report for the first time a clear and near-linear flux-rms correlation in the radio flux densities. Investigation of individual flares reveals in nearly all cases the peak corresponds to the transition from optically thick to thin to synchrotron emission, but an extended phase of particle acceleration is required in contrast to simple impulsive injection models. The largest radio flare is preceded by a phase of optical oscillations and followed one day later by a smaller but optically thin flare, likely due to ejecta interacting with the interstellar medium. Comparing the radio emission to contemporaneous X-ray and optical data, we find that the X-ray and radio measurements are correlated on all timescales from seconds to one day. Correlation with the optical flux densities is weak at short timescales, but becomes significant on timescales greater than a few hours. We evaluate the physical conditions (size, magnetic field and internal energy) associated with 86 individual radio flares, which in turn allows us to place a lower limit on the kinetic feedback over the 15 days of intense activity. If this energy was deposited locally to the source, as implied by the failure to detect jets on angular scales larger than milliarcsec, then we predict that a nova-like shell could have been formed., Accepted for publication in MNRAS. Data and high-resolution figures available on request to the authors

Monthly notices of the Royal Astronomical Society 515(1), 1365 - 1379 (2022). doi:10.1093/mnras/stac1601, We report on a search for persistent radio emission from the one-off fast radio burst (FRB) 20190714A, as well as from two repeating FRBs, 20190711A and 20171019A, using the MeerKAT radio telescope. For FRB 20171019A, we also conducted simultaneous observations with the High-Energy Stereoscopic System (H.E.S.S.) in very high-energy gamma rays and searched for signals in the ultraviolet, optical, and X-ray bands. For this FRB, we obtain a UV flux upper limit of |$1.39 \times 10^{-16}~{\rm erg\, cm^{-2}\, s^{-1}}$|Å^−1, X-ray limit of |$\sim 6.6 \times 10^{-14}~{\rm erg\, cm^{-2}\, s^{-1}}$| and a limit on the very high energy gamma-ray flux |$\Phi (E\gt 120\, {\rm GeV}) \lt 1.7\times 10^{-12}\, \mathrm{erg\, cm^{-2}\, s^{-1}}$|⁠. We obtain a radio upper limit of ∼15 |$\mu$|Jy beam^−1 for persistent emission at the locations of both FRBs 20190711A and 20171019A with MeerKAT. However, we detected an almost unresolved (ratio of integrated flux to peak flux is ∼1.7 beam) radio emission, where the synthesized beam size was ∼ 8 arcsec size with a peak brightness of |$\sim 53\, \mu$|Jy beam^−1 at MeerKAT and |$\sim 86\, \mu$|Jy beam^−1 at e-MERLIN, possibly associated with FRB 20190714A at z = 0.2365. This represents the first detection of persistent continuum radio emission potentially associated with a (as-yet) non-repeating FRB. If the association is confirmed, one of the strongest remaining distinction between repeaters and non-repeaters would no longer be applicable. A parallel search for repeat bursts from these FRBs revealed no new detections down to a fluence of 0.08 Jy ms for a 1 ms duration burst., Published by Oxford Univ. Press, Oxford

We present radio coverage of the 2019 outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3658, obtained with MeerKAT. We compare these data to contemporaneous X-ray and optical measurements in order to investigate the coupling between accretion and jet formation in this system, while the optical lightcurve provides greater detail of the outburst. The reflaring activity following the main outburst peak was associated with a radio re-brightening, indicating a strengthening of the jet in this phase of the outburst. We place quasi-simultaneous radio and X-ray measurements on the global radio:X-ray plane for X-ray binaries, and show they reside in the same region of luminosity space as previous outburst measurements, but significantly refine the correlation for this source. We also present upper limits on the radio emission from the accreting millisecond X-ray pulsar MAXI J0911-655 and the transitional Z/Atoll-type transient XTE J1701-462. In the latter source we also confirm that nearby large-scale structures reported in previous radio observations of the source are persistent over a period of ~15 years, and so are almost certainly background radio galaxies and not associated with the X-ray transient., Contains 9 pages and 3 figures, accepted for publication in MNRAS

Tidal disruption events (TDEs) are transient, multi-wavelength events in which a star is ripped apart by a supermassive black hole. Observations show that in a small fraction of TDEs, a short-lived, synchrotron emitting jet is produced. We observed the newly discovered TDE AT2022cmc with a slew of radio facilities over the first 100 days after its discovery. The light curve from the AMI-LA radio interferometer shows day-timescale variability which we attribute to a high brightness temperature emitting region as opposed to scintillation. We measure a brightness temperature of 2x10^15 K, which is unphysical for synchrotron radiation. We suggest that the measured high brightness temperature is a result of relativistic beaming caused by a jet being launched at velocities close to the speed of light along our line of sight. We infer from day-timescale variability that the jet associated with AT2022cmc has a relativistic Doppler factor of at least 16, which corresponds to a bulk Lorentz factor of at least 8 if we are observing the jet directly on axis. Such an inference is the first conclusive evidence that the radio emission observed from some TDEs is from relativistic jets because it does not rely on an outflow model. We also compare the first 100 days of radio evolution of AT2022cmc with that of the previous bright relativistic TDE, Swift J1644, and find a remarkable similarity in their evolution., 7 pages, 4 figures. Accepted for publication in MNRAS

The recurrent nova and symbiotic binary RS Oph erupted again in August 2021 for its eighth known outburst. As part of a multi-epoch and frequency campaign, we observed RS Oph 34 days after the outburst at 5 GHz with the European VLBI Network (EVN). The radio image is elongated over the east-west direction for a total extension of about 90 mas (or about 240 AU at the Gaia DR3 distance d=2.68 [-0.15/+0.17] kpc), and shows a bright and compact central component coincident with the Gaia astrometric position, and two lobes east and west of it, expanding perpendicular to the orbital plane. By comparing with the evolution of emission-line profiles on optical spectra, we found the leading edge of the lobes to be expanding at 7550 km/s, and i=54 deg as the orbital inclination of the binary. The 2021 radio structure is remarkably similar to that observed following the 2006 eruption. The obscuring role of the density enhancement on the orbital plane (DEOP) is discussed in connection to the time-dependent visibility of the receding lobe in the background to the DEOP, and the origin of the triple-peaked profiles is traced to the ring structure formed by the nova ejecta impacting the DEOP., A&A Letter to the Editor, in press

We present the results of a radio observing campaign on GRB 201216C, combined with publicly available optical and X-ray data. The detection of very high energy (VHE, >100GeV) emission by MAGIC makes this the fifth VHE GRB at time of publication. Comparison between the optical and X-ray light curves show that GRB 201216C is a dark GRB, i.e. the optical emission is significantly absorbed and is fainter than expected from the X-ray detections. Our e-MERLIN data also shows evidence of diffractive interstellar scintillation. We can study the column density along the line-of-sight to the GRB in both the host galaxy, from the damped optical light curve, and the Milky Way, via scintillation studies. We find that the afterglow is best modelled using a jet-cocoon geometry within a stellar wind environment. Fitting the data with a multi-component model we estimate that the optical, X-ray and higher-frequency radio data before ~25days originates from an ultra-relativistic jet with an isotropic equivalent kinetic energy of (0.6-10)x10^52erg and an opening angle of ~1-9deg. The lower-frequency radio emission detected by MeerKAT, from day 28 onwards, is produced by the cocoon with a kinetic energy that is between two and seven orders of magnitude lower (0.02-50)x10^48erg. The energies of the two components are comparable to those derived in simulations of such scenarios., 15 pages, 8 figures. Accepted to MNRAS

We present radio [1.3 GHz MeerKAT, 4-8 GHz Karl G. Jansky Very Large Array (VLA) and 15.5 GHz Arcminute Microkelvin Imager Large Array (AMI-LA)] and X-ray (Swift and MAXI) data from the 2019 outburst of the candidate Black Hole X-ray Binary (BHXB) EXO 1846-031. We compute a Hardness-Intensity diagram, which shows the characteristic q-shaped hysteresis of BHXBs in outburst. EXO 1846-031 was monitored weekly with MeerKAT and approximately daily with AMI-LA. The VLA observations provide sub-arcsecond-resolution images at key points in the outburst, showing moving radio components. The radio and X-ray light curves broadly follow each other, showing a peak on ~MJD 58702, followed by a short decline before a second peak between ~MJD 58731-58739. We estimate the minimum energy of these radio flares from equipartition, calculating values of $E_{\rm min} \sim$ 4$\times$10$^{41}$ and 5$\times$10$^{42}$ erg, respectively. The exact date of the return to `quiescence' is missed in the X-ray and radio observations, but we suggest that it likely occurred between MJD 58887 and 58905. From the Swift X-ray flux on MJD 58905 and assuming the soft-to-hard transition happened at 0.3-3 per cent Eddington, we calculate a distance range of 2.4-7.5\,kpc. We computed the radio:X-ray plane for EXO 1846-031 in the `hard' state, showing that it is most likely a `radio-quiet' BH, preferentially at 4.5 kpc. Using this distance and a jet inclination angle of $\theta$=73$^{\circ}$, the VLA data place limits on the intrinsic jet speed of $\beta_{\rm int} = 0.29c$, indicating sub-luminal jet motion., Comment: Accepted for publication in MNRAS on 20 September 2022, 17 pages, 6 figures

We present the results of our long term radio monitoring campaign at 1.3GHz (MeerKAT) and 15.5GHz (Arcminute Microkelvin Imager - Large Array, AMI-LA) for the outburst of the recently discovered neutron star X-ray binary Swift J1858.6-0814. Throughout the outburst, we observe radio emission consistent with a quasi-persistent, self-absorbed jet. In addition, we see two flares at MJD 58427 and 58530. The second flare allows us to place constraints on the magnetic field and minimum energy of the jet at 0.2G and 5x10^37erg, respectively. We use the multi-frequency radio data in conjunction with data from Swift-BAT to place Swift J1858.6-0814 on the radio/X-ray correlation. We find that the quasi-simultaneous radio and BAT data makes Swift J1858.6-0814 appears to bridge the gap in the radio/X-ray plane between atoll and Z sources. Furthermore, AMI-LA observations made whilst Swift J1858.6-0814 was in the soft state have allowed us to show that the radio emission during the soft state is quenched by at least a factor of four., Comment: 11 pages, 6 figures. Accepted by MNRAS

V341 Ara was recently recognised as one of the closest (d ~ 150 pc) and brightest (V~ 10) nova-like cataclysmic variables. This unique system is surrounded by a bright emission nebula, likely to be the remnant of a recent nova eruption. Embedded within this nebula is a prominent bow-shock, where the system's accretion disc wind runs into its own nova shell. In order to establish its fundamental properties, we present the first comprehensive multi-wavelength study of the system. Long-term photometry reveals quasi-periodic, super-orbital variations with a characteristic time-scale of 10-16 days and typical amplitude of ~1 mag. High-cadence photometry from TESS reveals for the first time both the orbital period and a "negative superhump" period. The latter is usually interpreted as the signature of a tilted accretion disc. We propose a recently developed disc instability model as a plausible explanation for the photometric behaviour. In our spectroscopic data, we clearly detect anti-phased absorption and emission line components. Their radial velocities suggest a high mass ratio, which in turn implies an unusually low white dwarf mass. We also constrain the wind mass-loss rate of the system from the spatially resolved [O iii] emission produced in the bow-shock; this can be used to test and calibrate accretion disc wind models. We suggest a possible association between V341 Ara and a "guest star" mentioned in Chinese historical records in AD1240. If this marks the date of the system's nova eruption, V341 Ara would be the oldest recovered nova of its class and an excellent laboratory for testing nova theory., Accepted in MNRAS

Soft set theory plays a vital role in solving many complicated problems with inherited uncertainty. An n -ary algebraic systems is a generalization of algebraic structures and it is the most natural way for the further development, deeper understanding of their properties. In this paper, we apply soft set theory to an n -ary algebraic systems and introduce the notions of soft n -ary groups and soft n -ary subgroups. Further, some operations on soft sets are extended to the former. Finally, we provide the characterization of soft n -ary subgroups over an n -ary group ( G , f ) and study their related properties.

Aims To assess outcomes of women in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) cohort with gestational diabetes mellitus (GDM) managed by lifestyle modification compared with women without hyperglycaemia in pregnancy. Methods Indigenous (n = 97) and Europid (n = 113) women managed by lifestyle modification were compared to women without hyperglycaemia (n = 235). Multivariate linear and logistic regressions assessed whether GDM-lifestyle women had poorer outcomes compared to women without hyperglycaemia. Results Women with GDM-lifestyle had higher body mass index and lower gestational weight gain than women without hyperglycaemia. On univariate analysis, gestational age at delivery was lower and induction rates were higher in women with GDM-lifestyle than without hyperglycaemia. On multivariable regression, GDM-lifestyle was associated with lower gestational age at delivery (by 0.73 weeks), lower birthweight z-score (by 0.26, p = 0.007), lower likelihood of large for gestational age (LGA) [OR (95% CI): 0.55 (0.28, 1.02), p = 0.059], and greater likelihood of labour induction [2.34 (1.49, 3.66), p Conclusion Women with GDM managed by lifestyle modification had higher induction rates and their offspring had lower birthweight z-scores, with a trend to lower LGA than those without hyperglycaemia in pregnancy. Further studies are indicated to explore reasons for higher induction rates.

We introduce a notion of t-fuzzy n-ary subgroup in an n-ary group (G, f) and have studied their related properties.

The aim of this study was to assess the impact of invitation to screening for type 2 diabetes and related cardiovascular risk factors on population mortality. This was a parallel-group population-based cohort study including all men and women aged 40–65 years, free of known diabetes, registered with a single practice in Ely, UK (n = 4,936). In 1990–1992, approximately one-third (n = 1,705) were randomly selected to receive an invitation to screening for diabetes (with an OGTT) and related cardiovascular risk factors. In the remaining two-thirds of the population, 1,705 individuals were randomly selected for invitation to screening in 2000–2003 and 1,526 were not invited at any point during the follow-up period. All individuals were flagged for mortality until January 2008. There were 345 deaths between 1990 and 1999 (median 10 years follow-up). Compared with those not invited, individuals who were invited to the 1990–1992 screening round had a non-significant 21% lower all-cause mortality (HR 0.79 [95% CI 0.63–1.00], p = 0.05) after adjustment for age, sex and deprivation. There were 291 deaths between 2000 and 2008 (median 8 years follow-up), with no significant difference in mortality between invited and non-invited participants in 2000–2003. Compared with the non-invited group, participants who attended for screening at any time point had a significantly lower mortality and those who did not attend had a significantly higher mortality. Invitation to screening was associated with a non-significant reduction in mortality in the Ely cohort between 1990 and 1999, but this was not replicated in the period 2000–2008. This study contributes to the evidence concerning the potential benefits of population screening for diabetes and related cardiovascular risk factors.

Cardiovascular disease (CVD) remains one of the leading causes of morbidity and mortality in developed countries. Over the past decade there has been much focus on the role of inflammation in the pathogenesis of atherosclerosis; to this end, there is increasing research on inflammatory factors such as C-reactive protein (CRP), interleukin-6 (IL-6), and fibrinogen (Fg). There is compelling evidence that physical activity (PA) and physical fitness (PF) protect against chronic disease. More recently, research has shown that exercise reduces CRP, IL-6, and Fg concentration in adults, and that this is often independent of adiposity. Although there are some data to suggest that this is similarly true for young people, there is inconsistency in the literature. The following review aims to illustrate what is known about the effects of PA and PF on inflammatory factors in young people aged 5-18 years.

In this paper ,we fuzzify the new class of algebraic structure introduced by Kim[5].In this fuzzification(called fuzzy KS-semigroups),we introduce the notions of fuzzy sub KS-semigroups,fuzzy KS-ideal,fuzzy KS-p-ideal and investigate some of their related properties.The purpose of this study is to implement the fuzzy set theory and ideal theory in the KS-semigroups.This fuzzification leads to development of new notions over fuzzy KS-semigroups. Mathematics Subject Classification: 06F35, 03G25, 03E72

Aims: To assess the impact of continual major National Health Service reorganization on commissioning, organizational and delivery arrangements for secondary care diabetes services. To explore how consultant diabetologists and diabetes specialist nurses perceive the issues facing diabetes specialist services in 2011 and how these have changed in the preceding decade.Methods: We used a longitudinal case study approach that combined quantitative and qualitative methods. Five locations in England were purposively selected to represent the wider diabetes specialist community, and seven semi-structured interviews were conducted. Interviews were recorded, transcribed verbatim and analysed using Framework analysis. Findings were compared with and contrasted to results from national quantitative surveys of diabetes specialist services undertaken in 2000 and 2006.Results: Clinicians viewed positively the expertise and commitment of multidisciplinary teams and their ability to adapt to new situations. Negative perceptions persisted throughout the decade, relating to the continual change that threatens to dismantle relationships and services which had taken many years to establish. Lack of resources, inadequate manpower planning and poor access to psychological support for people with diabetes remained constant themes from 2000 to 2011.Conclusions: A willingness to innovate and work differently to improve services was identified; however, clinicians must be supported through organizational changes to ensure people with diabetes receive high-quality care. The disruptive nature of organizational change was a recurrent theme throughout the decade. Periods of stability must exist within commissioning to allow relationships, which are key to integration, to be maintained and permit service improvements to develop.

Aims The aim of this study was to evaluate an innovative approach to the provision of primary care-based diabetes services in Bradford, UK. The service model differs from others in comprising 19 clinics which offer a specialist service, intermediate between primary and secondary care, to all patients within the Bradford area. Methods The study included: analysis of referral, attendance and register data; questionnaires to general practitioners (GPs) and specialist clinic providers; qualitative interviews with clinic and other professional staff and patients; and an economic analysis. Results The 19 clinics adopt a range of organizational models. In the first 3½ years, 2415 patients were referred. There was a significant reduction in out-patient attendances at hospital, but also a significant increase in overall patient attendances. Specialist clinic patients differed from hospital patients in being older and having had diabetes for longer since diagnosis. Ten of the 14 clinics run by practising GPs attracted more referrals from within their practices than from outside. GPs and patients across the city believed the clinics were valuable, the main benefits being geographical accessibility, availability of specialists in a community setting, short waiting times for first appointments at most clinics, and continuity of staff. Their reservations included a lack of strategic planning in the location of clinics, long waiting times at some clinics, and poor communication at some clinics with referring GPs. The cost of the primary care clinics is similar to hospital clinics. Conclusions This model of specialist primary care services offers an opportunity to develop diabetes services that are convenient to patients, popular with practitioners, and increase capacity. However, the shortcomings as well as the advantages of the model need to be addressed if it is to be implemented elsewhere or for other patient groups.

Aim To describe diabetes service provision in primary care in the UK. Methods Postal questionnaires were sent to all UK primary care organizations (PCOs), and to a sample of general practices in England and all practices in Wales and Scotland. The data collection period ended on 30 April 2001. Results Seventy-nine per cent of the PCOs and 40% of the practices provided usable information. There is evidence that respondents were not significantly biased in relation to their interest in diabetes care. Diabetes was included as a Health Improvement Programme (or equivalent) priority by 62% of PCOs and had been identified as a clinical governance priority by 27%. Sixty-five per cent had information about the ethnic composition of their general population, 57% had an estimate of the number of people with diabetes. Sixty-nine per cent had a local diabetes register but this was said to cover the entire local population in only 64% of these. At least one audit of diabetes care had been carried out (in the previous 5 years) in 75% and, in 76%, clinical guidelines on diabetes care were made available to practices. In the practices, 80% had a designated lead person for diabetes. Seventy-three per cent had at least one general practitioner with a special interest and 87% at least one nurse. Seventy-two per cent of practices ran specific diabetes clinics and 51% had a screening policy. Eighty-six per cent considered that they had adequate systems in place for the delivery of diabetes care. However, only 6% were able to offer a dedicated diabetes telephone help or advice line and only 9% an evening out of hours clinic. Regular practice meetings were held to discuss diabetes in 35%, whereas 39% had a formal shared care protocol. Fourteen per cent held regular joint meetings with the hospital-based team and in 38% there was membership of Diabetes UK for at least one partner or the practice itself. A third (34%) of responding practices were unsure whether a Local Diabetes Services Advisory Group or equivalent existed in their area. Geographical differences in service provision were identified with, for example, practices in London having fewer components in place that were specifically related to the provision of diabetes care. Single-handed practices, wherever they were situated, had in place fewer staff and facilities specifically for diabetes care.

Aim To examine the provision of, and variations in, podiatry and other services for diabetic foot care in the UK. Method A postal survey of secondary care providers of diabetes services in the UK in 2000. Results Following two reminders a 77% response rate was achieved. The responses indicated that 97% had a state-registered podiatrist attached to the service, providing three (median) sessions each week for diabetes care, although only 44% had availability at all diabetic clinics, and only 3% had availability at paediatric diabetic services. Podiatry access at all diabetic clinics increased the likelihood of associated preventative as opposed to reactive (‘trouble shooting’) care (P

Aims To examine the provision of, and variations in, dietetic services for diabetes in secondary care in the UK. Method A postal survey of all secondary care providers of diabetes services. Results There was a 77% response rate. A dedicated dietician supported diabetes services in 73% of responses, but only 45% were able to see newly diagnosed patients within 1 month. Only 3% of responses documented that dietetic services provided the recommended minimum 22 h weekly input to diabetes care, and an annual dietetic review was said to be available in 15%. An opportunity for more frequent visits was most likely if there was poor glycaemic control (78% of responses), particularly when services were provided by a dedicated diabetes dietician. Although dieticians frequently provided input to patient education (88%), specific training for this purpose and provision for continuing education of these individuals was less common (14% and 63%, respectively). Nutritional guidelines were available in 74%, but only 31% of responses documented current guidelines on obesity management. Of bids for additional dietetic resources, only 21% had been successful. There was evidence of regional variation in service provision, and no greater provision of dietetic services in areas with a large South Asian population and an expected high prevalence of diabetes. In broad terms, dietetic services for diabetes care had not altered in comparison with a similar survey in 1997. Conclusions The level of dietetic support of secondary care diabetes services remains dramatically lower than recommended in advisory documents, and appears to have changed little over the last 3 years. This is compounded by marked regional differences, and was no better in areas with a higher than average prevalence of diabetes. The survey also highlights the need for more co-ordinated and structured education and training of dieticians as well as more consistency in nutritional guidelines.

Determining the software quality and release time of the software is an important role of software reliability. Software reliability growth models (SRGMs) are applications of software reliability. The change-point is defined as the prominent change in the software testing time, in connection with the quality of a software error occurrence or error-detection phenomenon. As a result, the software reliability growth process, based on the change-point, affects the precision of the software reliability prediction, based on the SRGMs. To find the accurate total expected delivery cost with a suitable warranty period of the software system, a new cost model for the software system with the warranty and change-point phenomenon is proposed in this paper. The entire expected delivery cost and the reliability of the software system is calculated using the change-point SRGM. The optimal release time is calculated by reducing the overall estimated delivery cost for various desired reliability levels. Based on the proposed warranty cost model and the reliability of the software system, we have derived some optimal release policies. Numerical illustrations and interconnected discussed data are itemized. From the testing outcome, we get software release policies that provide a comprehensive analysis of software based on the total expected delivery cost with a suitable warranty period, desired level of reliability, and change-point. Moreover, these policies will be helpful for project managers to decide where to stop the testing for customer release at the exact time with a suitable warranty period.

Background This qualitative study aimed to explore the views of key stakeholders regarding the role that public health professionals have or should have in the provision of effective health care within the National Health Service. Methods A national (England) questionnaire survey generated a sample for qualitative telephone interviews and two site case studies. The interviews were conducted in three stages: first, 27 interviews were based on assessed reported levels of organizational activity, including non-respondents; next, views in six areas were consolidated by extra interviews; finally, two extra areas were visited for individual and group interviews. The interviews were analysed for salient themes. Results There was a widespread view that public health had not delivered its potential. Many Trusts currently wanted public health to have influence over commissioning, provide health needs assessments and epidemiological skills, and provide a strategic focus and unbiased advice. Evaluation of actual activity varied widely; local history and congruent personalities seemed to be associated with perceived success. In some cases there was mutual suspicion between Health Authorities and Trusts. Public health was often perceived by Trusts to have been marginalized. This perception was not shared by Public Health Consultants, who highlighted lack of resources as a reason for lack of involvement. The contribution of public health professionals working in Trusts was highly regarded. Barriers included overcoming initial prejudice and combating isolation within Trusts. There were four categories of response in respect of the potential future role for public health in implementing effective health care: no role; collaborative working between Health Authority Public Health Departments and Trusts; deployment of public health workers within Trusts, and an undecided group. Overall, the skills of public health, especially strategic vision and population perspectives, were seen as valuable but as yet unrealized. Conclusions Public health skills (but not necessarily professionals) may be valuable in implementing effective health care in Trusts. However, public health professionals must refocus and market their skills to Trusts if the discipline is to play a key role in this task.

Reports on a study which explored the views of key stakeholders regarding the meaning and implementation of effective health care and clinical governance in NHS Trusts, and the role for public health professionals. The authors used a national questionnaire survey to derive a sample for qualitative telephone interviews and two area case studies. The authors found that the meaning of effective health care and the means employed for implementation varied. Mergers were seen as hindrances to gaining organisational engagement whilst others, such as the White Paper on quality and the notion of clinical governance, were seen as facilitating. A widespread aspiration was a more integrated and corporate quality culture where quality was central, not marginal. The authors conclude that there is widespread concern among Trusts to change their culture and assert effective health care as a central value. Public health skills, rather than the discipline itself, are seen as important for such culture change.

We consider the problem of a thin smectic film placed on a periodically striped solid surface, with stripe width λ, and with the upper surface free. The striped surface–smectic fluid interfacial energy induces the lamellae to align perpendicularly to the surface. We show that in many cases both the bulk liquid and the free upper surface will undulate to relieve the frustration caused by the stripes. In marked contrast to the traditional Helfrich–Hurault instability we show that this new instability occurs under both extension and compression. As a concrete example we consider a symmetric diblock copolymer thin film melt, with bulk equilibrium AB–BA bilayer spacing L2. When L2 2λ they will be diminished.

Objective To evaluate the safety of a non-chlorofluorocarbon metered dose salbutamol inhaler. Design This was a postmarketing surveillance study, conducted under formal guidelines for company sponsored safety assessment of marketed medicines (SAMM). A non-randomised, non-interventional, observational design compared patients prescribed metered doses of salbutamol delivered by inhalers using either hydrofluoroalkane or chlorofluorocarbon as the propellant. Follow up was three months. Setting 646 general practices throughout the United Kingdom. Subjects 6614 patients with obstructive airways disease (1667 patient years of exposure). Main outcome measures Proportions of patients who were: admitted to hospital for respiratory diseases, reported adverse side effects, or withdrew because of adverse affects. Results There were no significant differences between the hydrofluoroalkane (HFA 134a) and chlorofluorocarbon inhaler groups in relation to the proportions of patients admitted to hospital for respiratory diseases (odds ratio 0.75; 95% confidence interval 0.51 to 1.08) or the proportions who reported adverse events (1.01; 0.88 to 1.17). However, more patients using the hydrofluoroalkane inhaler than the chlorofluorocarbon inhaler withdrew because of adverse events (3.8% and 0.9% respectively). Conclusion The hydrofluoroalkane inhaler was as safe as the chlorofluorocarbon inhaler when judged by hospital admissions and adverse affects. The study design successfully fulfilled the recommendations of the guidelines. Differences between postmarketing surveillance studies and randomised clinical trials in assessing safety were identified. These may lead to difficulties in the design of postmarketing surveillance studies.

OBJECTIVES—To determine the prevalence of multiple sclerosis in the Leeds Health District. METHODS—Multiple sources of case ascertainment were used—namely, neurology departments, hospital episode statistics, general practitioners, the Leeds branch of the Multiple Sclerosis Society, the West Yorkshire Multiple Sclerosis Therapy Centre, community physiotherapists and occupational therapists, the Leeds Wheelchair Centre, and the Young Disabled Unit. Data collection was from retrospective analysis of hospital and primary care case records. A population based incidence register was established by prospectively registering all new patients with diagnoses of multiple sclerosis. RESULTS—On prevalence day, 30 April 1996, 712 people with multiple sclerosis were identified living in Leeds (population 732 061), giving a prevalence of 97/105. The prevalence for definite and probable multiple sclerosis was 84/105, and for suspected multiple sclerosis it was 13/105. The sex ratio of prevalent people with multiple sclerosis was 2.79 to 1 women to men. The mean age of prevalent cases was 51years, the mean age at symptom onset was 34 years, and the mean duration of disease was 16 years. Forty cases were prospectively reported as incident cases from 1 November 1995 to 1 February 1996. CONCLUSIONS—The prevalence of multiple sclerosis in Leeds was found to be similar to that in the south of the United Kingdom but lower than that in Scotland. There is no evidence of a latitudinal gradient of increasing prevalence of multiple sclerosis from the south to the north of England.

The effects of thermally induced compositional disordering on the luminescence from two-dimensional and zero-dimensional ${\mathrm{In}}_{0.5}{\mathrm{Ga}}_{0.5}\mathrm{A}\mathrm{s}/\mathrm{G}\mathrm{a}\mathrm{A}\mathrm{s}$ structures are examined. Quantum-mechanical numerical calculations modeling changes in the quantum-well (QW) confining potential with interdiffusion have been used to obtain values for diffusivities. These show transient behavior. Activation energies for interdiffusion (3.5\ifmmode\pm\else\textpm\fi{}0.3 eV) are found to be similar to values reported for low-indium-content ${\mathrm{In}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}As/$GaAs QW's. In quantum-dot structures, larger blueshifts can be obtained than in QW's under similar conditions. Interdiffusion decreased activation energies for radiative recombination, reflecting changes in confining potentials, and affecting lifetime ratios in recombination processes. The latter were observed in all intermixed heterostructures regardless of dimensionality.

This study aimed to highlight geographical differences in childhood Type 1 (insulin dependent) diabetes mellitus (IDDM) by mapping incidence at 3 different geographical scales, within the northern English county of Yorkshire. Mapping techniques are applied to incident cases from a population-based regional register of childhood IDDM. The Yorkshire Children's Diabetes Register (YCDR) comprises 1310 children (0-14 years) diagnosed with IDDM from 1978-1990. Age standardized incidence rates (cases/100000/year) are given for administrative county, standardized incidence ratios (SIRs) are mapped by local government district and electoral ward. Heterogeneity between areas was assessed by a chi 2 test. At county level, incidence is 25% higher in Humberside (16.82 per 100000 per year) compared to West Yorkshire (12.21 per 100000 per year) (p < 0.001). SIRs for the 22 districts display significant heterogeneity (p < 0.001) with deficits in the urban areas of Kirklees (70 95% CI 57-85) and Bradford (81 95% CI 68-95) and significant excesses in the rural districts of Ryedale (147 95% CI 106-198), Beverley (149 95% CI 113-193), Holderness (166 95% CI 112-237) and Boothferry (186 95% CI 134-250). At the smallest scale, variation between wards is significant (p < 0.001) and low incidence in urban areas is notable. Geographical variation in the incidence of childhood IDDM may provide strong clues to its aetiology. Within Yorkshire, geographical distribution shows significant heterogeneity at three different scales. The magnitude of the variation is not explained by ethnic or genetic differences in the population and underlines the important influence of environmental factors in disease aetiology.

The objective was to describe, by means of a retrospective study of three years' routine District information (financial years 1991/92 to 1993/94), the in- and out-patient activity for patients with diabetes, and compare this with the non-diabetic population. The clinical resource usage by patients with diabetes relative to those without was estimated by (a) their relative probability of admission by specialty, (b) attendance rates at out-patient clinics, (c) primary diagnosis, and (d) operations and procedures. The setting was a District Health Authority with a population of 408 000. All in-patient and out-patient records were reclassified as attributable to a patient with or without diabetes by cross-referral to routine records of patients with identified diabetes from separate hospital databases. The main outcome measures were: (a) relative frequency, and crude and age-specific relative probability of admission by specialty, ICD9 primary diagnosis, and OPCS4 primary operation and procedure, and (b) out-patient attendance rates by specialty. Patients with diabetes were responsible for 5.5 % of admissions and 6.4 % of out-patient attendances. However, because of increased length of stay, patients with diabetes occupy 9.4 % of bed days. The relative risk of admission for diabetes related complications was: coronary heart disease 11.8 (95 % CI = 11.4–12.3), cerebrovascular disease 11.8 (10.8–12.8), neuropathy and peripheral vascular disease 15.6 (13.6–17.9), eye complications 10.4 (9.3–11.7), and renal disease 14.7 (12.6–17.3). Recognised diabetes related vascular complications accounted for at least 23 % of admissions of patients with diabetes. The relative risk of admission for diagnoses and procedures not known to be related to diabetes were similar for non-diabetic and diabetic patients. The pattern of out-patient activity mirrored that of the relative probability of admission. It is concluded that previous estimates of the proportion of NHS resources used for the treatment of patients with diabetes had been significantly underestimated. Patients with diabetes were found to occupy 1 in 10 non-obstetric, non-psychiatric beds. Many of these admissions were for diagnoses and procedures that are known to be related to diabetes.

A layer of short, grafted, main chain liquid crystalline polymers in a nematic solvent is confined to a slit. The polymers are modeled as bendable rods. This system can undergo a number of distortional transitions induced either by applied pressure or by an electric field. As well as Frederiks-like transitions the system can also exhibit columnar transitions in which the distorted domains are separated by undistorted regions. The coupling between the rods and nematic solvent implies that the system has an effective modulus due to both contributions. A combination of pressure and electric fields allows for the lowering of the Frederiks transition voltage to arbitrarily low values.

Although plasma insulin and triglyceride concentrations are positively correlated in many studies, the relationships between insulin resistance, insulin secretion and hypertriglyceridaemia remain unclear. To study these associations, subjects between the ages of 40 and 64 were randomly selected from a general practice register and invited to attend for a standard oral glucose tolerance test for measurement of insulin, triglyceride and non-esterified fatty acid concentrations. The study comprised 1122 subjects who were not previously known to have diabetes and who completed the test. Using the World Health Organisation criteria, 51 subjects were classified to have non-insulin-dependent diabetes mellitus, 188 had impaired glucose tolerance and 883 subjects had normal glucose tolerance. Triglyceride concentrations in subjects with glucose intolerance were elevated compared to those in control subjects, even after adjustment for age, obesity and gender (p < 0.001 for subjects with diabetes and p < 0.01 for those with impaired glucose tolerance compared to normal subjects). In separate multiple regression analyses for males and females, the most important determinants of the plasma triglyceride concentration were the area under the non-esterified fatty acid suppression curve (p < 0.001 in both genders) and the waist-hip ratio (p < 0.001 for men and < 0.01 for women). The fasting insulin concentration was independently associated with triglyceride concentration in women only (p < 0.01). The most important determinant of the area under the non-esterified fatty acid suppression curve in men was the 30-min insulin increment, a measure of insulin secretion, (p < 0.001) whereas for women age (p < 0.001) and the body mass index (p < 0.01) were the most important.

Liquid crystalline polymers in nematic solvents are studied theoretically. Three different scenarios are discussed: (i) confined polymers; (ii) grafted polymers and (iii) double brushes. The competition between nematic distortion, chain elasticity, excluded volume and nematic anchoring enables these systems to exhibit a number of remarkable properties. Notably, they can undergo tilting and anchoring transitions and show a quasi-piezoelectric effect. These phenomena may have applications in the design of liquid crystal displays and in making smart electro-optic, mechano-optic and electromechanic materials.

This brief report discusses the introduction of routine Glutamic Acid Decarboxylase Antibody (GADA) testing in primary care for newly diagnosed diabetes. GADA testing is well used and the majority of people found to be positive are initiated on insulin rapidly and progress to require a basal bolus regime.

This study examines CVD risk factors trends in Welsh adolescents between 2002 and 2007.CVD risk factor data was examined from two cross-sectional studies. The first study (73 participants; aged 12.9 ± 0.3 years) was completed in 2002. The second study (90 participants; aged 12.9 ± 0.4 years) was conducted in 2007. Measurements included body mass index (BMI), waist circumference (WC), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, fibrinogen (Fg) and high-sensitivity C-reactive protein (hs-CRP).In boys, mean BMI and WC were lower in 2007, although not significantly (p ≥ 0.05). In 2007, there were improvements in mean lipid, Fg and hs-CRP concentrations in both sexes (p0.05). In 2002, 42.8% of boys and 34.2% of girls were overweight or obese; in 2007, this was 23.7% and 28.9% for boys and girls, respectively. More adolescents in 2002 exceeded the recommended levels for lipids, Fg and hs-CRP.This is the only study to examine CVD risk factor trends in Welsh adolescents. Although overweight continues to be widespread in 12-13 year olds, this study did not identify significant mean changes in overweight and obesity between 2002 and 2007. Overall, the data presented a positive trend in lipid profile and inflammatory factors.

The swelling of main chain liquid crystalline polymers (LCPs) in good nematic solvents is theoretically studied, focusing on brushes of terminally anchored, grafted LCPs. The analysis is concerned with long LCPs, of length L, with n[sub 0] >> 1 hairpin defects. The extension behavior of the major axis, R[parallel], of these ellipsoidal objects gives rise to an Ising elasticity with a free energy penalty of F[sub el](R[parallel])/kT [approx] n[sub 0] [minus] n[sub 0](1 [minus] R[parallel][sup 2]/L[sup 2])[sup 1/2]. The theory of the extension behavior enables the formulation of a Flory type theory of swelling of isolated LCPs yielding R[parallel] [approx] exp(2U[sub h]/5kT)N[sup 3/5] and R [perpendicular] [approx] exp([minus]U[sub h]/10kT)N[sup 3/5], with N the degree of polymerization and U[sub h] the hairpin energy. It also allows the generalization of the Alexander model for polymer brushes to the case of grafted LCPs. The behavior of LCP brushes depends on the alignment imposed by the grafting surface and the liquid crystalline solvent. A tilting phase transition is predicted as the grafting density is increased for a surface imposing homogeneous, parallel anchoring. A related transition is expected upon compression of a brush subject to homeotropic, perpendicular alignment. The effect of magnetic or electric fieldsmore » on these phase transitions is also studied. The critical magnetic/electric field for the Frederiks transition can be lowered to arbitrarily small values by using surfaces coated by brushes of appropriate density.« less

The confinement of liquid crystalline polymers dissolved in a nematic solvent is analysed using a mean-field theory. For homeotropic anchoring the confinement triggers a tilting phase transition. The transition is reminiscent of the Frederiks transition, however it may be either first or second order.