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The study aim was to establish and quantify suicide risk following acute admissions for all major physical illnesses, for confirmatory purposes, from two independent information sources from different countries.
Record linkage of inpatient and death certificate data for 11 004 389 acute admissions for physical illnesses in England and 713 496 in Wales. The main outcome measure was standardised mortality ratios (SMRs) for suicide at 1 year following discharge from hospital.
There were 1781 suicides within 1 year of discharge in England (SMR = 1.7; 95% = 1.6–1.8) and 131 in Wales (SMR = 2.0; 1.7–2.3). Of 48 major physical illnesses that were associated with at least eight suicides in either country, there was high consistent suicide mortality (significant SMR >3) in both countries for constipation (SMR = 4.1 in England, 7.5 in Wales), gastritis (4.4 and 4.9) and upper gastrointestinal bleeding (3.4 and 4.5). There was high suicide mortality in one country for alcoholic liver disease, other liver disease and chronic pancreatitis; for epilepsy and Parkinson's disease; for diabetes, hypoglycaemia and hypo-osmolality & hyponatraemia; and for pneumonia, back pain and urinary tract infections.
There is little or no increased suicide mortality following acute admissions for most physical illnesses. Much of the increased suicide mortality relates to gastrointestinal disorders that are often alcohol related or specific chronic conditions, which may be linked to side effects from certain therapeutic medications. Acute hospital admissions for physical illnesses may therefore provide an opportunity for targeted suicide prevention among people with certain conditions, particularly alcohol related disorders.
A pneumocele occurs when an aerated cranial cavity pathologically expands; a pneumatocele occurs when air extends from an aerated cavity into adjacent soft tissues forming a secondary cavity. Both pathologies are extremely rare with relation to the mastoid. This paper describes a case of a mastoid pneumocele that caused hypoglossal nerve palsy and an intracranial pneumatocele.
A 46-year-old man presented, following minor head trauma, with hypoglossal nerve palsy secondary to a fracture through the hypoglossal canal. The fracture occurred as a result of a diffuse temporal bone pneumocele involving bone on both sides of the hypoglossal canal. Further slow expansion of the mastoid pneumocele led to a secondary middle fossa pneumatocele. The patient refused treatment and so has been managed conservatively for more than five years, and he remains well.
While most patients with otogenic pneumatoceles have presented acutely in extremis secondary to tension pneumocephalus, our patient has remained largely asymptomatic. Aetiology, clinical features and management options of temporal bone pneumoceles and otogenic pneumatoceles are reviewed.
Concerns relating to increased use of psychotropic medication contrast with those of under-treatment and under-recognition of common mental disorders in children and young people (CYP) across developed countries. Little is known about the indications recorded for antidepressant prescribing in primary care in CYP.
This was an electronic cohort study of routinely collected primary-care data from a population of 1.9 million, Wales, UK. Poisson regression was undertaken to model adjusted counts of recorded depression symptoms, diagnoses and antidepressant prescriptions. Associated indications were explored.
3 58 383 registered patients aged 6–18 years between 1 January 2003 and 31 December 2013 provided a total of 19 20 338 person-years of follow-up. The adjusted incidence of antidepressant prescribing increased significantly [incidence rate ratio (IRR) for 2013 = 1.28], mainly in older adolescents. The majority of new antidepressant prescriptions were for citalopram. Recorded depression diagnoses showed a steady decline (IRR = 0.72) while depression symptoms (IRR = 2.41) increased. Just over half of new antidepressant prescriptions were associated with depression (diagnosis or symptoms). Other antidepressant prescribing, largely unlicensed, was associated with diagnoses such as anxiety and pain.
Antidepressant prescribing is increasing in CYP while recorded depression diagnoses decline. Unlicensed citalopram prescribing occurs outside current guidelines, despite its known toxicity in overdose. Unlicensed antidepressant prescribing is associated with a wide range of diagnoses, and while accepted practice, is often not supported by safety and efficacy studies. New strategies to implement current guidance for the management of depression in CYP are required.
Two cases of hospital-acquired listeriosis were linked to a commercially produced, pasteurized ice cream mix. Manufacturers should implement safety measures from the Food Safety Modernization Act to minimize the risk of Listeria contamination. Dietary guidelines for persons at high risk of listeriosis may need revision to recognize the potential risk from pasteurized products.
Attentional impairment is a core cognitive feature of major depressive disorder (MDD) and bipolar disorder (BD). However, little is known of the characteristics of response time (RT) distributions from attentional tasks. This is crucial to furthering our understanding of the profile and extent of cognitive intra-individual variability (IIV) in mood disorders.
A computerized sustained attention task was administered to 138 healthy controls and 158 patients with a mood disorder: 86 euthymic BD, 33 depressed BD and 39 medication-free MDD patients. Measures of IIV, including individual standard deviation (iSD) and coefficient of variation (CoV), were derived for each participant. Ex-Gaussian (and Vincentile) analyses were used to characterize the RT distributions into three components: mu and sigma (mean and standard deviation of the Gaussian portion of the distribution) and tau (the ‘slow tail’ of the distribution).
Compared with healthy controls, iSD was increased significantly in all patient samples. Due to minimal changes in average RT, CoV was only increased significantly in BD depressed patients. Ex-Gaussian modelling indicated a significant increase in tau in euthymic BD [Cohen's d = 0.39, 95% confidence interval (CI) 0.09–0.69, p = 0.011], and both sigma (d = 0.57, 95% CI 0.07–1.05, p = 0.025) and tau (d = 1.14, 95% CI 0.60–1.64, p < 0.0001) in depressed BD. The mu parameter did not differ from controls.
Increased cognitive variability may be a core feature of mood disorders. This is the first demonstration of differences in attentional RT distribution parameters between MDD and BD, and BD depression and euthymia. These data highlight the utility of applying measures of IIV to characterize neurocognitive variability and the great potential for future application.
To systematically summarise the peer-reviewed literature relating to the aetiology, clinical presentation, investigation and treatment of geniculate neuralgia.
Articles published in English between 1932 and 2012, identified using Medline, Embase and Cochrane databases.
The search terms ‘geniculate neuralgia’, ‘nervus intermedius neuralgia’, ‘facial pain’, ‘otalgia’ and ‘neuralgia’ were used to identify relevant papers.
Fewer than 150 reported cases were published in English between 1932 and 2012. The aetiology of the condition remains unknown, and clinical presentation varies. Non-neuralgic causes of otalgia should always be excluded by a thorough clinical examination, audiological assessment and radiological investigations before making a diagnosis of geniculate neuralgia. Conservative medical treatment is always the first-line therapy. Surgical treatment should be offered if medical treatment fails. The two commonest surgical options are transection of the nervus intermedius, and microvascular decompression of the nerve at the nerve root entry zone of the brainstem. However, extracranial intratemporal division of the cutaneous branches of the facial nerve may offer a safer and similarly effective treatment.
The response to medical treatment for this condition varies between individuals. The long-term outcomes of surgery remain unknown because of limited data.
High occupational suicide rates are often linked to easy occupational access to a method of suicide. This study aimed to compare suicide rates across all occupations in Britain, how they have changed over the past 30 years, and how they may vary by occupational socio-economic group.
We used national occupational mortality statistics, census-based occupational populations and death inquiry files (for the years 1979–1980, 1982–1983 and 2001–2005). The main outcome measures were suicide rates per 100 000 population, percentage changes over time in suicide rates, standardized mortality ratios (SMRs) and proportional mortality ratios (PMRs).
Several occupations with the highest suicide rates (per 100 000 population) during 1979–1980 and 1982–1983, including veterinarians (ranked first), pharmacists (fourth), dentists (sixth), doctors (tenth) and farmers (thirteenth), have easy occupational access to a method of suicide (pharmaceuticals or guns). By 2001–2005, there had been large significant reductions in suicide rates for each of these occupations, so that none ranked in the top 30 occupations. Occupations with significant increases over time in suicide rates were all manual occupations whereas occupations with suicide rates that decreased were mainly professional or non-manual. Variation in suicide rates that was explained by socio-economic group almost doubled over time from 11.4% in 1979–1980 and 1982–1983 to 20.7% in 2001–2005.
Socio-economic forces now seem to be a major determinant of high occupational suicide rates in Britain. As the increases in suicide rates among manual occupations occurred during a period of economic prosperity, carefully targeted suicide prevention initiatives could be beneficial.
We have integrated recent research results in the curriculum of the University of Maryland, while leaving the basics intact. This allows us to teach the fundamental laws and to show the students how these help us to answer questions that are of importance today. This can be done as part of a laboratory and as part of a class. In the laboratory classes, we emphasize what is measured (the main topic), then measure samples recently done in the literature. If available, we measure two samples and have a discussion on what are the differences. These are then related to the manner the samples have been grown. In the classes, we show the basic equation or relation, and introduce how it can answer a question that is pertinent to today's research.
Electron and ion beams can be used to deposit thin films and etch surfaces using gas phase precursors. However, the generation of undesirable gas phase products and the diffusion of the reactive species beyond the region irradiated by the electron or ion beam can limit selectivity. Tn this paper, the feasibility of processing condensed precursors such as diborane, tri-methyl aluminum, ammonia and water at 78 K with low energy (100–1000 eV) electron and ion beams (Ar+, N2+ and H2+) ranging in current density from 50 nA to several μ a per cm2 is examined. It was found that boron, boron nitride and stoichiometric aluminum oxide films could be deposited from the condensed volatile species using charged particle beams and some of the physical and chemical aspects and limitations of this new technique are discussed.
The effects of Si and Kr ion implantation on the crystallization kinetics of amorphous COSi2 have been investigated by differential scanning calorimetry and in situ sheet resistance measurement. Without ion implantation, the crystallization of coevaporated COSi2 is characterized by three dimensional growth from preexisting nuclei. When the as-deposited COSi2 is implanted with Si or Kr ions at liquid nitrogen temperature, the kinetics of the subsequent crystallization is significantly altered. A 180 keV 5×1015 cm−2Si ion implantation increases the crystallization temperature by 34°C. When the Si dose is below 1×1015 cm−2, ion implantation causes a sharp decrease in the crystallization kinetic parameter defined by the Avrami equation. The amount of decrease is shown to scale with the deposited nuclear energy. At higher doses, the kinetic parameter continues to decrease with increasing dose but at a much reduced rate.
Ni foils and samples consisting of bilayers of Ni or Fe on Al, Ti or Si were implanted at room temperature with 15N+ ions to fluences of around 1×l017 N/cm2. The concentration depth profiles of 15N were determined with nuclear reaction analysis before and after vacuum annealing. It was found that the penetrability for N atoms of the surface and the solid/solid interface plays an important role in the N redistribution during implantation or annealing. The formation of a nitride layer or nitride clusters in Ni and Fe was deduced. Parameters for N migration determined for the metals under investigation are discussed in terms of models.
We have extended our recent work [1,2] on buried suicide formation by Ni diffusion into a buried amorphous silicon layer to the case where silicide formation is at lower temperatures on silicon substrates which have been preamorphized. The reaction of metal atoms from a 12 nm Ni film evaporated on top of a 65 nm thick surface amorphous layer formed by 35 keV Si+ ion implantation has been investigated at temperature ≤400 °C. Rutherford Backscattering Spectrometry (RBS) with channeling, cross-sectional transmission electron microscopy (XTEM), X-ray diffraction and four-point-probe measurements were used to determine the structure, interfacial morphology, composition and resistivity of the silicide films. It has been found that an increased rate of silicidation occurs for amorphous silicon with respect to crystalline areas permitting a selective control of the silicon area to be contacted during silicide growth. Vacuum furnace annealing at 360 °C for 8 hours followed by an additional step at 400 °C for one hour produces a continuos NiSi2 layer with a resistivity 44 μΩ cm.
OH radicals were photochemically substituted for fluorine atoms in the teflon surface by using an ArF excimer laser light and an Al(OH)3 solution. This method is simple and can be performed in air atmosphere. In the process, the teflon film was placed on the Al(OH)3 which were dissolved in NaOH water solution; the ArF excimer laser light was irradiated the sample surface and the solution. By irradiating the laser, the surface was defluorinated by the aluminium atoms photodissociated from the Al(OH)3 solution, and the dangling bonds which were formed in the defluorinated surface combined with the OH radicals also photodissociated. The hydrophilic property of the photomodified surface was evaluated by the measurement of the contact angle with water. The defluorination and the OH radicals substitution were inspected by the XPS analysis and the ATR-FTIR measurement.
In order to understand the properties of intrinsic point defects and their interactions at high defect concentrations GaAs wafers were irradiated at 4.5 K with 3 MeV electrons up to a dose of 4.1019 e-/cm2. The irradiated samples were investigated by X-ray Diffraction and optical absorption spectrocopy. The defect production increases linearly with irradiation dose and characteristic differences are observed for the two sublattices. The Ga-Frenkel pairs are strongly correlated and are characterized by much larger lattice relaxations (Vrel=2–3 atomic volumes) as compared to the As-Frenkel pairs (Vrel ≈ 1 at.voL). The dominating annealing stage around 300 K is attributed to the mobility of the Ga interstitial atoms whereas the As-interstitial atoms can recombine with their vacancies only around 500 K. These results are compared to those for InP, ZnSe and Ge. Implications for the understanding of the damage after ion irradiation and implantation are discussed.
The ionized cluster beam (ICB) deposition was use to stabilize the metastable zinc-blende (ZB) MnTe films directly on GaAs (100) substrates at 300 °C with MnTe cluster ion beam. Influences of the ionization and the acceleration voltage on film properties were investigated by the reflection high-energy electron diffraction (RHEED), optical reflection, Raman scattering, and photoluminescence. The ZB-MnTe was stabilized by 3kV acceleration of the MnTe cluster beam. These results showed that the ICB deposition is useful to get compounds having crystalline phase different from the structures observed io equilibrium-grown bulk crystals.
The temperature dependence of amorphization dose for zircon under 1.5 MeV Kr ion irradiation has been investigated using the HVEM-Tandem Facility at Argonne National Laboratory. Three regimes were observed in the amorphization dose-temperature curve. In the first regime (15 to 300 K), the critical amorphization dose increased from 3.06 to 4.5 ions/nm2. In the second regime (300 to 473 K), there is little change in the amorphization dose. In the third regime (> 473 K), the amorphization dose increased exponentially to 8.3 ions/nm2 at 913 K. This temperature dependence of amorphization dose can be described by two processes with different activation energies (0.018 and 0.31 eV respectively) which are attributed to close pair recombination in the cascades at low temperatures and radiation-enhanced epitaxial recrystallization at higher temperatures. The upper temperature limit for amorphization of zircon is estimated to be 1100 K. The ion-mass dependence of the amorphization dose (in dpa) has also been discussed in terms of the energy to recoils based on data obtained from He, Ne, Ar, Kr, Xe irradiations and a 238Pu-doped sample.
About 2 μm thick commercial coatings of TiN on high speed steel substrates were implanted at RT with Ar ions of 95 keV energy to doses between 0.1–1.0×1017 ions/cm2. An ultramicrohardness machine was used to measure hardness, and a (sapphire) ball-on-disk machine to measure wear, friction and adhesion. Hardness enhancements up to about 50% were observed as dose increased. However, at the highest dose, hardness reduced by nearly 2 times the unimplanted value. Friction coefficient and relative wear are correlated and reduce with ion dose. Films undergo brittle fracture during sliding tests. These results are found to be very sensitive to small changes in relative humidity. All implants lead to improved wear and adhesion as compared to an unimplanted surface. These results are discussed in terms of ion damage, accumulation of Ar gas bubbles and a possible break-up of the TiN phase during ion bombardment.
The crystallization of Sn-implanted amorphous silicon was studied as a function of tin implant dose and annealing conditions by transmission electron microscopy. The films were implanted at an energy of 110 keV with a dose in the range of 5 × 1014 to 5×1016 cm−2 and were annealed at a temperature in the range of 450°C to 550°C. An enhanced rate of crystallization in amorphous Si-Sn films compared to the non-implanted amorphous silicon films during thermal annealing was observed. The crystallization process of Si films implanted with tin at a dose of 2.5×1016 cm−2 or less is very similar to unimplanted silicon films except higher nucleation rates and shorter crystallization time were observed with increasing tin dose. Films implanted with tin at a dose of 2.5×1016 cm−2 or more display extremely rapid crystallization (3 hours at 450°C) and very fine grain structure (10 nm); no substantial grain growth has been observed during lurther annealing, but some single crystal-like areas were formed. In-situ annealing of silicon implanted to 5×1016 cm−2 showed that the crystallization process is enhanced by the formation of the liquid tin phase.
A study on ion beam synthesis of buried α- and β-FeSi2 in >100< Si is presented. Phase formation has been investigated as a function of implant and anneal temperature. Layer characterization was performed by RBS, XRD, resistivity, spreading resistance and Hall effect measurements. Orientation effects in the layers have been observed depending on the implant temperature. Transport measurements show that die holes are the majority carriers in the semiconducting layers.