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An epitaxial NdFeAs(O,F) thin film of 90 nm thickness grown by molecular beam epitaxy on MgO single crystal with Tc = 44.2 K has been investigated regarding a possible vortex glass–liquid transition. The voltage–current characteristics show excellent scalability according to the vortex-glass model with a static critical exponent ν of around 1.35 and a temperature-dependent dynamic exponent z increasing from 7.8 to 9.0 for the investigated temperature range. The large and non-constant z values are discussed in the frame of 3D vortex glass, thermally activated flux motion, and inhomogeneity broadening.
Foodborne non-typhoidal salmonellosis causes approximately 1 million illnesses annually in the USA. In April 2015, we investigated a multistate outbreak of 65 Salmonella Paratyphi B variant L(+) tartrate(+) infections associated with frozen raw tuna imported from Indonesia, which was consumed raw in sushi. Forty-six (92%) of 50 case-patients interviewed ate sushi during the week before illness onset, and 44 (98%) of 45 who specified ate sushi containing raw tuna. Two outbreak strains were isolated from the samples of frozen raw tuna. Traceback identified a single importer as a common source of tuna consumed by case-patients; this importer issued three voluntary recalls of tuna sourced from one Indonesian processor. Four Salmonella Weltevreden infections were also linked to this outbreak. Whole-genome sequencing was useful in establishing a link between Salmonella isolated from ill people and tuna. This outbreak highlights the continuing foodborne illness risk associated with raw seafood consumption, the importance of processing seafood in a manner that minimises contamination with pathogenic microorganisms and the continuing need to ensure imported foods are safe to eat. People at higher risk for foodborne illness should not consume undercooked animal products, such as raw seafood.
Mycobacterium marinum, a bacterium found in freshwater and saltwater, can infect persons with direct exposure to fish or aquariums. During December 2013, the New York City Department of Health and Mental Hygiene learned of four suspected or confirmed M. marinum skin or soft tissue infections (SSTIs) among persons who purchased whole fish from Chinese markets. Ninety-eight case-patients with non-tuberculous mycobacteria (NTM) SSTIs were identified with onset June 2013–March 2014. Of these, 77 (79%) were female. The median age was 62 years (range 30–91). Whole genome sequencing of clinical isolates revealed two main clusters and marked genetic diversity. Environmental samples from distributors yielded NTM though not M. marinum. We compared 56 case-patients with 185 control subjects who shopped in Chinese markets, frequency-matched by age group and sex. Risk factors for infection included skin injury to the finger or hand (odds ratio [OR]: 15·5; 95% confidence interval [CI]: 6·9–37·3), hand injury while preparing fish or seafood (OR 8·3; 95% CI 3·8–19·1), and purchasing tilapia (OR 3·6; 95% CI 1·1–13·9) or whiting (OR 2·7; 95% CI 1·1–6·6). A definitive environmental outbreak source was not identified.
It has been shown that for many epidemic models, the stochastic theory leads to essentially the same results as the deterministic theory provided that one identifies mean values with the functions calculated from the deterministic differential equations (cf. ). If one considers a generalization of Bailey's simple epidemic for a fixed population of size N, represented schematically by where I refers to an infected, S refers to a susceptible, and α and β are appropriate rate constants, then it is evident that at time t = ∞, the expected number of infected individuals must be zero provided that β > 0. If x(t) denotes the number of infected at time t, then the deterministic model is summarized by
The theory of epidemics has been formulated as a deterministic theory and as a stochastic theory. There has been little work, except for a recent paper by Bailey , on the transition between the two formulations. In this paper we present an alternate formulation to that of Bailey that leads to a perturbation method more easily extendible to higher orders.
Background: Planning for neurology training necessitated a reflection on the experience of graduates. We explored practice characteristics, and training experience of recent graduates. Methods: Graduates from 2010-2014 completed a survey. Results: Response rate was 37% of 211. 56% were female. 91% were adult neurologists. 65% practiced in an outpatient setting. 63% worked in academics. 85% completed subspecialty training (median 1 year). 36% work 3 days a week or less. 82% took general call (median 1 night weekly). Role preparation was considered very good or excellent for most; however poor or fair ratings were 17% in advocacy and 8% in leadership. Training feedback was at least “good” for 87%. Burnout a few times a week or more was noted by 5% (6% during residency, particularly PGY1 and 5). 64% felt overly burdened by paperwork. Although most felt training was adequate, it was poor or fair at preparing for practice management (85%) and personal balance (55%). Most conditions were under-observed in training environment. Many noted a need for more independent practice development and community neurology. Conclusions: Although our training was found to be very good, some identified needs included advocacy training, and more training in general neurology in the longitudinal outpatient/community settings.
ET And is a binary system with a B9 Si star as the main component (Porb = 48.308d, e=0.46). Controversial claims in the literature concerning pulsation with periods ranging from few minutes to few hours and with variable amplitudes indicated a challenging target and motivated us to organize several photometric and spectroscopic observing campaigns. The problem with pulsation of ET And is that Teff and log g put this star in the cool domain of Slowly Pulsating B-type (SPB) stars, but the pulsation periods would be too short by a factor of about four, relatively to the shortest hitherto known periods for SPB stars.
Walborn (1970, 1971) observationally found that OB stars showed nitrogen and carbon abundance anomalies in their atmospheres. Schönberner et al. (1988) found that OBN stars had helium enriched atmospheres. Several different suggestions have been made so far to explain the abundance anomalies in these stars (Paczynski 1973; Walborn 1976; Bolton and Rogers 1978). Maeder (1987) and Weiss et al. (1988) call attention to some possible effects of rotation in mixing chemical elements in Wolf-Rayet stars and B-supergiant stars respectively. They suggested that rotational mixing could explain the high He/H ratios and the high N/C and N/O ratios in the progenitor of 1987A Supernova. Saio et al. (1988) in an attempt to explain the nitrogen and helium enhancement in the progenitor of SN 1987A invoked extensive mixing in their models. They pointed out that such an effective mixing may be produced by rapid rotation. Such observations and ideas were the motivation for the present study.
In the past several Wolf–Rayet stars have been investigated photometrically by different authors to search for fast pulsations. So far all results were negative. However, in 1992 Blecha, Schaller & Maeder published a 627sec period with a semi–amplitude of about 2.5mmag for the Southern Wolf–Rayet star WR40 (HD96548).
The Diffuse Infrared-Background Experiment (DIRBE) on the Cosmic Background Explorer (COBE) satellite is a 10-band absolute photometer covering the wavelengths 1–300 microns using photovoltaic, photoconductive, and bolometric detectors. The input is via a 19-cm, off-axis, highly-baffled Gregorian telescope, with the detectors located at a pupil plane so they share the same field of view (0.7 × 0.7 degrees). The whole assembly is mounted inside a 1.4 K; super-fluid, liquid-He dewar, which is shared with the Far Infrared Absolute Spectrometer (FIRAS) instrument. Each day half of the sky is surveyed, as the line-of-sight of the DIRBE is canted 30 degrees to the COBE spin axis. The whole sky is fully observed in 6 months, as the spin axis precesses at about 1 degree per day. At present each sky pixel has been observed at least once. The basic findings on the general brightness of the sky - Zodiacal light and galaxy - are provided, as well as a synopsis of the advantages and disadvantages associated with a space-borne observatory. The relationship of our experience and findings with respect to possible future missions and their scientific goals is presented.
The Cosmic Background Explorer, launched November 18, 1989, has nearly completed its first full mapping of the sky with all three of its instruments: a Far Infrared Absolute Spectrophotometer (FIRAS) covering 0.1 to 10 mm, a set of Differential Microwave Radiometers (DMR) operating at 3.3, 5.7, and 9.6 mm, and a Diffuse Infrared Background Experiment (DIRBE) spanning 1 to 300 µm in ten bands. A preliminary map of the sky derived from DIRBE data is presented. Initial cosmological implications include: a limit on the Comptonization y parameter of 10−3, on the chemical potential μ parameter of 10−2, a strong limit on the existence of a hot smooth intergalactic medium, and a confirmation that the dipole anisotropy has the spectrum expected from a Doppler shift of a blackbody. There are no significant anisotropies in the microwave sky detected, other than from our own galaxy and a cosθ dipole anisotropy whose amplitude and direction agree with previous data. At shorter wavelengths, the sky spectrum and anisotropies are dominated by emission from ‘local’ sources of emission within our Galaxy and Solar System. Preliminary comparison of IRAS and DIRBE sky brightnesses toward the ecliptic poles shows the IRAS values to be significantly higher than found by DIRBE at 100 μm. We suggest the presence of gain and zero-point errors in the IRAS total brightness data. The spacecraft, instrument designs, and data reduction methods are described.
There are striking global inequities in our knowledge of the incidence, aetiology, and outcome of psychotic disorders. For example, only around 10% of research on incidence of psychotic disorders originates in low- and middle-income countries. We established INTREPID I to develop, implement, and evaluate, in sites in India (Chengalpet), Nigeria (Ibadan), and Trinidad (Tunapuna-Piarco), methods for identifying and recruiting untreated cases of psychosis, as a basis for investigating incidence and, subsequently, risk factors, phenomenology, and outcome. In this paper, we compare case characteristics and incidence rates across the sites.
In each site, to identify untreated cases of psychoses in defined catchment areas, we established case detection systems comprising mental health services, traditional and spiritual healers, and key informants.
Rates of all untreated psychoses were 45.9 (per 1 00 000 person-years) in Chengalpet, 31.2 in Ibadan, and 36.9 in Tunapuna-Piarco. Duration of psychosis prior to detection was substantially longer in Chengalpet (median 232 weeks) than in Ibadan (median 13 weeks) and Tunapuna-Piarco (median 38 weeks). When analyses were restricted to cases with a short duration (i.e. onset within preceding 2 years) only, rates were 15.5 in Chengalpet, 29.1 in Ibadan, and 26.5 in Tunapuna-Piarco. Further, there was evidence of age and sex differences across sites, with an older average age of onset in Chengalpet and higher rates among women in Ibadan.
Our findings suggest there may be differences in rates of psychoses and in the clinical and demographic profiles of cases across economically and socially distinct settings.
A patient with no risk factors for malaria was hospitalized in New York City with Plasmodium falciparum infection. After investigating all potential sources of infection, we concluded the patient had been exposed to malaria while hospitalized less than 3 weeks earlier. Molecular genotyping implicated patient-to-patient transmission in a hospital setting.
Infect. Control Hosp. Epidemiol. 2015;37(1):113–115
In this paper we investigate the physical processes that lead to the growth and decay of magnetic flux in and near sunspots.
An initial phase of rapid growth is characterized by the emergence of magnetic flux from the deep convection zone. As the flux rope rises through the surface the magnetic field is swept to the junctions of the supergranular network where sunspots are formed. These flux concentrations follow the footpoints of the emergent flux rope as they rapidly move apart.
This prospective experimental study sought to examine the unique effects of emotion dysregulation and impulsivity on risky behaviours over time. To this end, 20 African American women enrolled in a historically Black university in the southern United States were randomly assigned to receive one of two brief empirically supported skills training modules (i.e., emotion modulation [EM] or impulsivity reduction [IR]). Participants completed measures of emotion dysregulation, impulsivity, and past-week risky behaviours before (pre-) and one week after (post-) the experimental manipulation. Participants assigned to the EM condition reported significant improvements from pre- to post-manipulation in overall emotion dysregulation (as well as all specific dimensions of emotion dysregulation other than lack of emotional awareness), as well as two dimensions of impulsivity: negative and positive urgency. Participants assigned to the IR condition reported a significant decrease in one dimension of impulsivity (lack of premeditation) from pre- to post-manipulation. Findings also revealed a significant effect of time on risky behaviours, with participants reporting significantly fewer past-week risky behaviours at the post- (vs. pre-) manipulation assessment. Finally, changes in emotion dysregulation from pre- to post-manipulation accounted for the observed reduction in risky behaviours over time (above and beyond changes in impulsivity dimensions). Results highlight the relevance of emotion dysregulation to risky behaviours and suggest that treatments targeting emotion dysregulation may be useful in reducing risky behaviours.