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An improved understanding of diagnostic and treatment practices for patients with rare primary mitochondrial disorders can support benchmarking against guidelines and establish priorities for evaluative research. We aimed to describe physician care for patients with mitochondrial diseases in Canada, including variation in care.
We conducted a cross-sectional survey of Canadian physicians involved in the diagnosis and/or ongoing care of patients with mitochondrial diseases. We used snowball sampling to identify potentially eligible participants, who were contacted by mail up to five times and invited to complete a questionnaire by mail or internet. The questionnaire addressed: personal experience in providing care for mitochondrial disorders; diagnostic and treatment practices; challenges in accessing tests or treatments; and views regarding research priorities.
We received 58 survey responses (52% response rate). Most respondents (83%) reported spending 20% or less of their clinical practice time caring for patients with mitochondrial disorders. We identified important variation in diagnostic care, although assessments frequently reported as diagnostically helpful (e.g., brain magnetic resonance imaging, MRI/MR spectroscopy) were also recommended in published guidelines. Approximately half (49%) of participants would recommend “mitochondrial cocktails” for all or most patients, but we identified variation in responses regarding specific vitamins and cofactors. A majority of physicians recommended studies on the development of effective therapies as the top research priority.
While Canadian physicians’ views about diagnostic care and disease management are aligned with published recommendations, important variations in care reflect persistent areas of uncertainty and a need for empirical evidence to support and update standard protocols.
Mental disorders in children and adolescents have an impact on educational attainment.
To examine the temporal association between attainment in education and subsequent diagnosis of depression or self-harm in the teenage years.
General practitioner, hospital and education records of young people in Wales between 1999 and 2014 were linked and analysed using Cox regression.
Linked records were available for 652 903 young people and of these 33 498 (5.1%) developed depression and 15 946 (2.4%) self-harmed after the age of 12 but before the age of 20. Young people who developed depression over the study period were more likely to have achieved key stage 1 (age 7 years) but not key stage 2 (age 11) (hazard ratio (HR) = 0.79, 95% CI 0.74–0.84) milestones, indicating that they were declining in academic attainment during primary school. Conversely, those who self-harmed were achieving as well as those who did not self-harm in primary school, but showed a severe decline in their attainment during secondary school (HR = 0.72, 95% CI 0.68–0.78).
Long-term declining educational attainment in primary and secondary school was associated with development of depression in the teenage years. Self-harm was associated with declining educational attainment during secondary school only. Incorporating information on academic decline with other known risk factors for depression/self-harm (for example stressful life events, parental mental health problems) may improve risk profiling methods.
Militant groups, like all organizations, carefully consider the tactics and strategies that they employ. We assess why some militant organizations diversify into multiple tactics while others limit themselves to just one or a few. This is an important puzzle because militant organizations that employ multiple approaches to violence are more likely to stretch state defenses, achieve tactical success, and threaten state security. We theorize that militant organizations respond to external pressure by diversifying their tactics to ensure their survival and continued relevance, and that the primary sources of such pressure are government repression and interorganizational competition. We find consistent support for these propositions in tests of both the Global Terrorism Database (GTD) and Minorities at Risk Organizational Behavior (MAROB) data sets. We bolster these findings with an additional specification that employs ethnic fractionalization in the first stage of a multi-process recursive model. These findings are relevant not only for academic research but for policy as well. While it is difficult for countries to anticipate the character of future tactical choices, they may be able to anticipate which groups will most readily diversify and thereby complicate counterterrorism efforts.
South West London and St George's Mental Health NHS Trust developed a system of weekend new patient reviews by higher trainees to provide senior medical input 7 days a week. To evaluate the effectiveness of these reviews, the notes for all patients admitted over 3 months were examined. The mean length of stay for patients before and after the introduction of the weekend new patient reviews were compared via unpaired t-test.
A total of 88 patients were seen: 84.4% of patients were seen within 24 h of admission. Higher trainees instituted some changes in 78.9% of patients. The most frequent action was to modify medication, in 47.8%. The average length of stay after the introduction of weekend reviews was not significantly different.
Weekend reviews of newly admitted patients by higher trainees is a feasible method for providing senior input to patients admitted out of hours.
A study of polynya characteristics in East Antarctica was undertaken using ice concentrations derived from special sensor microwave/imager data for the period July 1987-August 1994. The areas of polynyas were defined as having an ice concentration ≤75%. The analysis revealed a total of 28 coastal polynyas within the study region. The spatial and temporal variability in areal extent was quantified. The timing of mean maximum areal extent varied from June to October. The bathymetry and wind regime at each polynya site was examined to gauge the relative importance of these parameters in polynya formation and maintenance. In 20 locations, shallow banks and shoals form grounding zones for icebergs and anchoring sites for fast ice, which form barriers to the predominantly westward drift of the pack ice; elsewhere north-south coastal protrusions or alignments form similar barriers. The subsequent removal of newly formed sea ice from the lee of such barriers by katabatic and synoptic winds maintains areas of reduced ice concentration and open water. Very few coastal polynyas are attributed solely to katabatic outflow. The combined influence of bathymetry, topography and winds is responsible for the characteristics of the majority of polynyas. Many were considered to be marginal, characterised by occasional periods when the ice concentration falls below 75%. An analysis of annual winter totals of areas with ice concentrations < 75% shows no trends in total polynya areal extent over the period 1987-94. Known locations of emperor penguin (Aptenodytes forsteri) rookeries were also found to be associated with the locations of coastal polynyas.
Although close binaries are believed to be of importance in the dynamical evolution of globular clusters, searches for such binaries have produced mostly negative results, aside from x-ray sources. Two dwarf novae which are possible cluster members are known (Margon and Downes 1983) and two classical nova candidates have been found. The crowded field around the nova observed in 1860 close to the center of M80 makes ground-based recovery of that star impossible with present techniques. Here we report on our attempt to recover the star which erupted in 1938 about 30″ (0.8 core radii) from the center of M14.
We present the results of a search for low-mass companions around a sample of young, solar-analog stars using the Hōkūpa'a adaptive optics instrument mounted on the Gemini North 8 m telescope. Out of 31 stars observed, one binary brown dwarf system was found as a companion to the star HD 130948 (HIP 72567), as confirmed by proper motion and near-IR spectra. Orbital motion between the two brown dwarfs was measured, but our 14 month time baseline is inadequate to accurately measure the system's dynamical mass. Upcoming spectroscopic observations of the brown dwarfs will measure their lithium absorption lines to provide a more accurate age estimate of the system. The eventual dynamical mass determination coupled with the age determination will provide a valuable check of brown dwarf evolutionary models.
We have completed a direct narrow-band/broad-band Schmidt-plate survey of large areas of the southern Milky Way for new Wolf-Rayet stars as faint as 19th b magnitude. The 31 newly detected stars in the completed survey are amongst the reddest and/or most distant known in the Galaxy. We have obtained spectra of all candidate WR stars in the 22 fields stretching from l = 282° to l = 341° in longitude, and Δb = 3.5° in latitude, covering about 180 square degrees. We also observed two isolated Milky Way fields centered at l = 0° and l = 8°. Eighteen new WR stars are reported here for the first time. Combined with the 13 new WR stars we have already reported in Carina, our list of 31 new Galactic WR stars reaches 3–4 magnitudes fainter than previous surveys. Thirteen of the 18 new WR stars reported here are of subtype WN, while five are of subtype WC. Our new WR stars clearly demonstrate an increasing WN/WC number ratio with increasing Galactocentric distance.
A week before the Reagan-Gorbachev summit in Washington, a group of American and Soviet scholars met in Moscow to explore how a new spirit of cooperation could be applied in Africa. The challenge was to find ways of transforming the well-established pattern of hostile competition between the two countries in that area of the world into one of collaboration for the mutual benefit of both countries and Africa. The results of the Moscow workshop are highly promising.
Offspring of mothers with depression are at heightened risk of psychiatric disorder. Many mothers with depression have comorbid psychopathology. How these co-occurring problems affect child outcomes has rarely been considered.
To consider whether the overall burden of co-occurring psychopathology in mothers with recurrent depression predicts new-onset psychopathology in offspring.
Mothers with recurrent depression and their adolescent offspring (9–17 years at baseline) were assessed in 2007 and on two further occasions up to 2011. Mothers completed questionnaires assessing depression severity, anxiety, alcohol problems and antisocial behaviour. Psychiatric disorder in offspring was assessed using the Child and Adolescent Psychiatric Assessment.
The number of co-occurring problems in mothers (0, 1 or 2+) predicted new-onset offspring disorder (odds ratio (OR) = 1.80, 95% CI 1.17–2.77, P = 0.007). Rates varied from 15.7 to 34.8% depending on the number of co-occurring clinical problems. This remained significant after controlling for maternal depression severity (OR = 1.73, 95% CI 1.03–2.89, P = 0.040).
The burden of co-occurring psychopathology among mothers with recurrent depression indexes increased risk of future onset of psychiatric disorder for offspring. This knowledge can be used in targeting preventive measures in children at high risk of psychiatric disorder.
To obtain patient-generated data relating to the management of their chronic obstructive pulmonary disease (COPD) in Primary Care before hospitalisation with exacerbation.
Previous audits of COPD have shown high rates of hospital admission and readmission. There is significant interest in understanding the reasons so that useful preventative strategies may be developed. As part of the 2008 UK COPD audit, which comprised 9716 cases of COPD admission across 97% of acute units, we obtained a sample of patient-generated data to assess understanding of COPD, use of healthcare resources, access to care and self-management in Primary Care prior to hospitalisation with exacerbation. We anticipated the data would provide useful insight for directing improvement strategies.
A paper-based, anonymised survey was completed by patients identified as having exacerbation by participating hospital teams. Response rate was an estimated 46%.
Understanding and awareness of COPD was very variable. Patients noticed symptoms of COPD exacerbation, particularly change in sputum, for some time prior to hospitalisation but tended not to react promptly to these changes. A minority had self-care plans, many bypassed Primary Care Services and there was variable access to a named health professional or advice. Patients using home oxygen and nebulisers were at particular risk of admission.
We conclude these sick patients use a lot of resources and the data suggest a need to support and educate them in the proactive management of exacerbation. There needs to be better ‘exacerbation planning’ so patients know how to recognise and treat flare-up but also whom to contact in the event of decline. Targetted support should be considered for the most vulnerable, particularly those using home oxygen and nebulisers, who have very high rates of hospitalisation.
Epitaxial ZnGa2O4 and Sr2CeO4 thin-film phosphors were successfully grown on (100) MgO, YSZ, and SrTiO3 single crystal substrates using pulsed laser ablation. Cathodoluminescence efficiency was remarkably enhanced by adding lithium in the ZnGa2O4 and ZnGa2O4:Mn for both blue and green light emitting thin-film phosphors. The highest efficiencies, in this experiment, were 0.35 and 0.29 lm/W at 1kV for as-deposited blue and green zinc gallate phosphor films, respectively. In case of Sr2CeO4 films, the highest luminescence was 0.14 lm/W at 1kV and 0.26 A/m2 for films annealed at 1000°C in air.
As part of an ongoing investigation to characterize the properties and structure of zinc halide-tellurium oxide glasses, we report preliminary measurements of the optical properties of several Nd- and Er-doped tellurites. Measurements include florescence lifetimes and estimates of the theoretical radiative lifetimes (as obtained by traditional Judd-Ofelt analysis of optical absorption spectra) as well as phonon sideband studies sensitive to vibrational characteristics near the rare earth ion. The response of these optical features to the substitution of alternative halides is examined.
Thin films have been deposited by rf magnetron sputtering from a stoichiometric Ta2Zn3O8 ceramic target (3ZnO + 1Ta2O5). Negative ion re-sputtering effects have been observed in the stoichiometric Ta2Zn3O8 target and have been attributed to O ion formation from primarily Ta-O bonds. Zinc deficient thin films were deposited as a result of the preferential re- sputtering of Zn versus Ta. The negative ion re-sputtering effects are exacerbated at higher powers and lower pressure. This observation is correlated to the oxygen ion transport through the dark space and the plasma, which ultimately controls the energy distribution of the oxygen particles that arrive at the substrate. To circumvent the negative ion re-sputtering, a mosaic ZnO-Ta target was sputtered, which resulted in stoichiometric and luminescent thin films.
Isotactic Polypropylene (iPP) nanocomposites with low concentrations of multiwall carbon nanotubes (CNTs) 0-1% were studied, using differential scanning calorimetry and Avrami analysis. The nanocomposites were isothermally crystallized at 135°C, in order to measure the effect of nanotubes on the kinetics of crystallization. In our study there is a great effect of the CNTs on the iPP crystallization kinetics. The Avrami analysis shows increase in the crystallization rate constant and constancy the Avrami exponent with increase of the CNTs concentration. The full width at half maximum (FWHM) of the heat flow exotherm and the peak time for crystallization (tp) change dramatically. For iPP, the carbon nanotubes serve as nucleation agents to speed up the crystallization process.
Gottlob Frege (1848–1925) was unquestionably one of the most important philosophers of all time. He trained as a mathematician, and his work in philosophy started as an attempt to provide an explanation of the truths of arithmetic, but in the course of this attempt he not only founded modern logic but also had to address fundamental questions in the philosophy of language and philosophical logic. Frege is generally seen (along with Russell and Wittgenstein) as one of the fathers of the analytic method, which dominated philosophy in English-speaking countries for most of the twentieth century. His work is studied today not just for its historical importance but also because many of his ideas are still seen as relevant to current debates in the philosophies of logic, language, mathematics and the mind. The Cambridge Companion to Frege provides a route into this lively area of research.
Frege was born in 1848 in Wismar, a small port on the Baltic coast in Mecklenberg. His father, who ran a private school for girls there, died when he was eighteen, and his mother took over the running of the school in order to be able to provide for the university education of Frege and his younger brother. Frege was encouraged in this by a young teacher at his father's school called Leo Sachse. Sachse had attended university in Jena, and Frege went there too in 1869, lodging in the same room that Sachse had rented there before him. Frege's studies in Jena consisted mainly of courses in mathematics and chemistry. The only philosophy was a course on Kant's critical philosophy given by Kuno Fischer. From Jena Frege went on to Göttingen, where he took further courses in mathematics and physics and wrote a dissertation, 'On a Geometrical Representation of Imaginary Forms in the Plane'. His only philosophy course at Göttingen was one on the philosophy of religion given by Hermann Lotze. After five semesters, Frege returned to Jena to submit a further dissertation for his venia docendi (i.e. licence to teach in the university).
From Jena Frege went on to Göttingen, where he took further courses in mathematics and physics and wrote a dissertation, ‘On a Geometrical Representation of Imaginary Forms in the Plane’. His only philosophy course at Göttingen was one on the philosophy of religion given by Hermann Lotze. After fi ve semesters, Frege returned to Jena to submit a further dissertation for his venia docendi (i.e. licence to teach in the university). The title of this second dissertation was ‘Methods of Calculation based on an Extension of the Concept of Quantity’. Neither dissertation exhibits more than a passing interest in logic or the philosophy of mathematics.