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There is variation regarding the use of surgery and interventional radiological techniques in the management of epistaxis. This review evaluates the effectiveness of surgical artery ligation compared to direct treatments (nasal packing, cautery), and that of embolisation compared to direct treatments and surgery.
A systematic review of the literature was performed using a standardised published methodology and custom database search strategy.
Thirty-seven studies were identified relating to surgery, and 34 articles relating to interventional radiology. For patients with refractory epistaxis, endoscopic sphenopalatine artery ligation had the most favourable adverse effect profile and success rate compared to other forms of surgical artery ligation. Endoscopic sphenopalatine artery ligation and embolisation had similar success rates (73–100 per cent and 75–92 per cent, respectively), although embolisation was associated with more serious adverse effects (risk of stroke, 1.1–1.5 per cent). No articles directly compared the two techniques.
Trials comparing endoscopic sphenopalatine artery ligation to embolisation are required to better evaluate the clinical and economic effects of intervention in epistaxis.
Suicidal behaviour is an under-reported and hidden cause of death in most low- and middle-income countries (LMIC) due to lack of national systematic reporting for cause-specific mortality, high levels of stigma and religious or cultural sanctions. The lack of information on non-fatal suicidal behaviour (ideation, plans and attempts) in LMIC is a major barrier to design and implementation of prevention strategies. This study aims to determine the prevalence of non-fatal suicidal behaviour within community- and health facility-based populations in LMIC.
Twelve-month prevalence of suicidal ideation, plans and attempts were established through community samples (n = 6689) and primary care attendees (n = 6470) from districts in Ethiopia, Uganda, South Africa, India and Nepal using the Composite International Diagnostic Interview suicidality module. Participants were also screened for depression and alcohol use disorder.
We found that one out of ten persons (10.3%) presenting at primary care facilities reported suicidal ideation within the past year, and 1 out of 45 (2.2%) reported attempting suicide in the same period. The range of suicidal ideation was 3.5–11.1% in community samples and 5.0–14.8% in health facility samples. A higher proportion of facility attendees reported suicidal ideation than community residents (10.3 and 8.1%, respectively). Adults in the South African facilities were most likely to endorse suicidal ideation (14.8%), planning (9.5%) and attempts (7.4%). Risk profiles associated with suicidal behaviour (i.e. being female, younger age, current mental disorders and lower educational and economic status) were highly consistent across countries.
The high prevalence of suicidal ideation in primary care points towards important opportunities to implement suicide risk reduction initiatives. Evidence-supported strategies including screening and treatment of depression in primary care can be implemented through the World Health Organization's mental health Global Action Programme suicide prevention and depression treatment guidelines. Suicidal ideation and behaviours in the community sample will require detection strategies to identify at risks persons not presenting to health facilities.
A large-scale public health emergency, such as a severe influenza pandemic, can generate large numbers of critically ill patients in a short time. We modeled the number of mechanical ventilators that could be used in addition to the number of hospital-based ventilators currently in use.
We identified key components of the health care system needed to deliver ventilation therapy, quantified the maximum number of additional ventilators that each key component could support at various capacity levels (ie, conventional, contingency, and crisis), and determined the constraining key component at each capacity level.
Our study results showed that US hospitals could absorb between 26,200 and 56,300 additional ventilators at the peak of a national influenza pandemic outbreak with robust pre-pandemic planning.
The current US health care system may have limited capacity to use additional mechanical ventilators during a large-scale public health emergency. Emergency planners need to understand their health care systems’ capability to absorb additional resources and expand care. This methodology could be adapted by emergency planners to determine stockpiling goals for critical resources or to identify alternatives to manage overwhelming critical care need. (Disaster Med Public Health Preparedness. 2015;9:634–641)
Investigation of an outbreak of Clostridium difficile infection (CDI) at a hemodialysis facility revealed evidence that limited intrafacility transmission occurred despite adherence to published infection control standards for dialysis clinics. Outpatient dialysis facilities should consider CDI prevention, including environmental disinfection for C. difficile, when formulating their infection control plans.
Infect. Control Hosp. Epidemiol. 2015;36(8):972–974
Information concerning the carcinogenicity of bracken fern (Pteridium aquilinum) in different species and organs is reviewed. Various methods used in attempts to identify the plant components responsible are described and the results evaluated. Reference is made to recent and current research in this field (University College of North Wales, Bangor) and includes mutagenic and sterility studies, and the introduction of teratogenic screening by injection of Japanese quail eggs. The many problems still challenging bracken workers are indicated, and a final section deals with the potential hazard to human health in an attempt to link experimental work with epidemiological surveys of human cancer incidence. One important result of the study of bracken carcinogenicity is that active components, previously thought to be harmless, can be found in a wide variety of regular dietary items.
Amorphous hydrogenated silicon carbide alloy films (a-SiC:H) were produced by the decomposition of methane and silane in a glow discharge deposition system. A deposition rate of 13 Å/sec was achieved for good quality films. Amorphous SiC:H films of p+ type and n+ type of a band gap of 1.86 eV and 1.8 eV and the activation energy of 0.4 eV and 0.23 eV, respectively were obtained. Results show that p+ type and n+ type a-SiC:H films can be good window layers and good diffusion barriers for indium in polyimide/metal/n-i-p(p-i-n)/ITO amorphous silicon solar cells.
Small-particle clusters of CdS, CdSe, CdTe, PbS, and PbSe have been synthesized in aqueous solution. Absorption spectra with very sharp maxima were obtained for extremely small clusters (diameters < 30 Å). However, when clusters grow the excitonic absorption bands gradually decrease and the sharp maxima are replaced by broad shoulders. Cadmium chalcogenide clusters capped with 3-mercapto-l, 2-propanediol can be collected as stable solids with the same properties as original clusters. A method for the incorporation of semiconductor clusters in transparent silicate glasses has been developed. This technique relies on the low temperature sol-gel process, and silane alkoxide as the starting material. The absorption spectra of the clusters in the glasses are identical to those of the starting aqueous solutions. Excess charge carriers on PbS and CdS clusters lead to a blue shift in the optical absorption edge of semiconductors. The appearance of this shift depends critically on the method of colloid preparation and surface chemistry.
Hydrogenated amorphous silicon films were produced from silane/hydrogen and silane/helium gas mixtures by RF glow discharge. We examined the optical and electrical properties of films produced with these gas mixtures, at various RF power levels and silane fractions. Film quality was analyzed by measuring the dark and photoconductivity, optical band gap, and activation energy. Optical emission spectroscopy was also used as a diagnostic tool for studying the plasma during glow discharge depositions. Experimental results indicate that amorphous silicon films made from silane/helium mixtures exhibit improved optoelectronic properties, higher deposition rates, and higher emission intensity ratios (ISiH/IH) as compared to films produced from silane/hydrogen mixtures. In preparing films from silane/helium mixtures, the onset of dust/powder formation occurs at considerably higher RF powers as compared to silane/hydrogen, thus making this approach an attractive commercial option for depositing films at high rates.
There is a growing interest in the deposition and processing of thin films at low temperatures to eliminate the inherent problems associated with high temperature processing. Photo enhanced processing is one of the techniques which has received considerable interest. One of the major limitations of photo processing is the lack of sufficiently intense ultra-violet (UV) sources. To date the low pressure Hg lamp has been the only available source for large area UV processing and this has limited the types and quality of films deposited.
In this paper we will outline the design of a novel, variable wavelength excimer discharge lamp which can be used for depositing thin films over large substrate areas. We shall also discuss the direct (i.e. without intermediate photosensitisation reactions) photo induced deposition of thin silicon dioxide films using SiH4 and N2O which are photo dissociated by 126nm photons generated by the excimer lamp described.
Cadmium telluride layers were grown on InSb substrates by organometallic vapor phase epitaxy and examined using secondary ion mass spectrometry (SIMS), photoluminescence (Pb) and double crystal x-ray diffraction (DCD). The substrate temperature and the nature of the surface prior to growth are shown to be the most important parameters which influence the quality of CdTe layers. Growth on diethyltelluride (DETe) stabilized InSb substrates resulted in CdTe growth with a misorientation of about 4 minutes of arc with respect to the substrates. On the other hand, the grown layers followed the orientation of the substrates when a dimethylcadmium (DMCd) stabilized InSb was used. Growth at 350°C resulted in the smallest x-ray rocking curve (DCRC) full width at half maximum (FWHM) of about 20 arc seconds.
Thin films of lead scandium tantalate (Pb(Sc½Ta½)03) (PST) have been prepared by a novel modified sol-gel process. The process involves two deposition steps. In the first, layers of amorphous ScTaO4 are deposited by spin coating a solution of metallorganic compounds of scandium and tantalum. A film of lead oxide is then deposited onto the surface using a solution of lead acetate, and the process repeated to obtain thicker films. After firing the composite film, a pale yellow transparent film of PST is obtained. The films are highly orientated and 100% perovskite.
The film's electrical properties have been measured against field and temperature, showing a strong induced pyroelectric response (peak value of 3.8 x 10−3C/m2K), peak permittivities of 4500 and low loss. The figure-ofmerit of these films (11 x 10−5Pa−½) indicates a performance equivalent to conventional bulk ceramic pyroelectric wafers prepared by slicing, lapping and polishing of ceramic blocks.
The ultimate usefulness of oxynitride glasses and fibers depends upon the minimization or elimination of metallic defects that arise during processing. Despite this, the origins and chemistry of such defects in oxynitride glasses have received scant attention in the literature. The defects reduce glass transparency and cause oxynitride glass fibers to fail at relatively low stress levels. The same types of defects undoubtedly occur in the grain boundary glass phase of sintered Si3N4with unknown effects on material properties.
Exampls are shown of Si-rich metallic defects in oxynitride glasses, and their effects on glass and fiber properties are discussed. Chemical reactions that produce the defects are considered, as are chemical analysis results supporting the proposed reaction mechanisms.
An epidemic of diarrhoea with two distinct waves affected a village of 1375 people in southern India in 1983. The first wave of the epidemic, from the last week of December 1982, had a sharp peak in January 1983 and was over by March. Echovirus type 11 was isolated from patients, who also had a serum antibody response to the virus. During the second wave of the epidemic, from May to September 1983, the clinical features were different and Shigella flexneri was isolated without significant viral isolates. Infection during the first wave did not protect from the second wave. Virus isolation was in human intestinal tumourderived differentiated epithelial cell lines; such cell lines may be useful for the isolation and identification of entcroviruses in clinical samples.
The Working Group on Mental Health and Psychosocial Support was convened as part of the 2009 Harvard Humanitarian Action Summit. The Working Group chose to focus on ethical issues in mental health and psychosocial research and programming in humanitarian settings. The Working Group built on previous work and recommendations, such as the Inter-Agency Standing Committee's Guidelines on Mental Health and Psychosocial Support in Emergency Settings.
The objective of this working group was to address one of the factors contributing to the deficiency of research and the need to develop the evidence base on mental health and psychosocial support interventions during complex emergencies by proposing ethical research guidelines. Outcomes research is vital for effective program development in emergency settings, but to date, no comprehensive ethical guidelines exist for guiding such research efforts.
Working Group members conducted literature reviews which included peer-reviewed publications, agency reports, and relevant guidelines on the following topics: general ethical principles in research, cross-cultural issues, research in resource-poor countries, and specific populations such as trauma and torture survivors, refugees, minorities, children and youth, and the mentally ill. Working Group members also shared key points regarding ethical issues encountered in their own research and fieldwork.
The group adapted a broad definition of the term “research”, which encompasses needs assessments and data gathering, as well as monitoring and evaluation. The guidelines are conceptualized as applying to formal and informal processes of assessment and evaluation in which researchers as well as most service providers engage. The group reached consensus that it would be unethical not to conduct research and evaluate outcomes of mental health and psychosocial interventions in emergency settings, given that there currently is very little good evidence base for such interventions. Overarching themes and issues generated by the group for further study and articulation included: purpose and benefits of research, issues of validity, neutrality, risk, subject selection and participation, confidentiality, consent, and dissemination of results.
The group outlined several key topics and recommendations that address ethical issues in conducting mental health and psychosocial research in humanitarian settings. The group views this set of recommendations as a living document to be further developed and refined based on input from colleagues representing different regions of the globe with an emphasis on input from colleagues from low-resource countries.