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There is a scarcity of specialist trainers and supervisors for psychosocial interventions in low- and middle-income countries. A cascaded model of training and supervision was developed to sustain delivery of an evidence-based peer-delivered intervention for perinatal depression (the Thinking Healthy Programme) in rural Pakistan. The study aimed to evaluate the model.
Mixed methods were employed as part of a randomised controlled trial of the intervention. Quantitative data consisted of the peers' competencies assessed during field training and over the implementation phase of the intervention, using a specially developed checklist. Qualitative data were collected from peers and their trainers through 11 focus groups during the second and third year of intervention rollout.
Following training, 43 peers out of 45 (95%) achieved at least a ‘satisfactory’ level of competency (scores of ⩾70% on the Quality and Competency Checklist). Of the cohort of 45 peers initially recruited 34 (75%) were retained over 3 years and showed sustained or improved competencies over time. Qualitatively, the key factors contributing to peers' competency were use of interactive training and supervision techniques, the trainer–peer relationship, and their cultural similarity. The partnership with community health workers and use of primary health care facilities for training and supervision gave credibility to the peers in the community.
The study demonstrates that lay-workers such as peers can be trained and supervised to deliver a psychological intervention using a cascaded model, thus addressing the barrier of scarcity of specialist trainers and supervisors.
Introduction: The Ottawa SAH Rule was developed to identify patients at high-risk for subarachnoid hemorrhage (SAH) who require investigations and the 6-Hour CT Rule found that computed tomography (CT) was 100% sensitive for SAH 6 hours of headache onset. Together, they form the Ottawa SAH Strategy. Our objectives were to assess: 1) Safety of the Ottawa SAH Strategy and its 2) Impact on: a) CTs, b) LPs, c) ED length of stay, and d) CT angiography (CTA). Methods: We conducted a multicentre prospective before/after study at 6 tertiary-care EDs January 2010 to December 2016 (implementation July 2013). Consecutive alert, neurologically intact adults with a headache peaking within one hour were included. SAH was defined by subarachnoid blood on head CT (radiologists final report); xanthochromia in the cerebrospinal fluid (CSF); >1x106/L red blood cells in the final tube of CSF with an aneurysm on CTA. Results: We enrolled 3,669 patients, 1,743 before and 1,926 after implementation, including 185 with SAH. The investigation rate before implementation was 89.0% (range 82.9 to 95.6%) versus 88.4% (range 85.2 to 92.3%) after implementation. The proportion who had CT remained stable (88.0% versus 87.4%; p=0.60), while the proportion who had LP decreased from 38.9% to 25.9% (p<0.001), and the proportion investigated with CTA increased from 18.8% to 21.6% (p=0.036). The additional testing rate (i.e. LP or CTA) diminishedfrom 50.1% to 40.8% (p<0.001). The proportion admitted declined from 9.8% to 7.3% (p=0.008), while the mean length of ED stay was stable (6.2 +/− 4.0 to 6.4 +/− 4.1 hours; p=0.45). For the 1,201 patients with CT 6 hours, there was an absolute decrease in additional testing (i.e. LP or CTA) of 15.0% (46.6% versus 31.6%; p<0.001). The sensitivity of the Ottawa SAH Rule was 100% (95%CI: 98-100%), and the 6-Hour CT Rule was 95.3% (95%CI: 88.9-98.3) for SAH. Five patients with early CT had SAH with CT reported as normal: 2 unruptured aneuryms on CTA and presumed traumatic LP (determined by treating neurosurgeon); 1 missed by the radiologist on the initial interpretation; 1 dural vein fistula (i.e. non-aneuyrsmal); and 1 profoundly anemic (Hgb 63g/L). Conclusion: The Ottawa SAH Strategy is highly sensitive and can be used routinely when SAH is being considered in alert and neurologically intact headache patients. Its implementation was associated with a decrease in LPs and admissions to hospital.
The initial assessment of epistaxis patients commonly includes: first aid measures, observations, focused history taking, and clinical examinations and investigations. This systematic review aimed to identify evidence that informs how the initial assessment of these patients should be conducted.
A systematic review of the literature was performed using a standardised methodology and search strategy.
Seventeen articles were included. Factors identified were: co-morbidity, intrinsic patient factors, coagulation screening and ice pack use. Hypertension and anticoagulant use were demonstrated to adversely affect outcomes. Coagulation screening is useful in patients on anticoagulant medication. Four studies could not be accessed. Retrospective methodology and insufficient statistical analysis limit several studies.
Sustained ambulatory hypertension, anticoagulant therapy and posterior bleeding may be associated with recurrent epistaxis, and should be recorded. Oral ice pack use may decrease severity and can be considered as first aid. Coagulation studies are appropriate for patients with a history of anticoagulant use or bleeding diatheses.
The aim of this feasibility trial was to evaluate the feasibility and acceptability of the locally adapted Group Problem Management Plus (PM+) intervention for women in the conflict affected settings in Swat, Pakistan.
This mixed-methods study incorporated a quantitative component consisting of a two arm cluster randomised controlled feasibility trial, and qualitative evaluation of the acceptability of the Group PM+ to a range of stakeholder groups. For the quantitative component, on average from each of the 20 Lady Health Workers (LHWs) catchment area (20 clusters), six women were screened and recruited for the trial with score of >2 on the General Health Questionnaire and score of >16 on the WHO Disability Assessment Schedule. These LHW clusters were randomised on a 1 : 1 allocation ratio using a computer-based software through a simple randomisation method to the Group PM+ intervention or Enhanced Usual Care. The Group PM+ intervention consisted of five weekly sessions of 2 h duration delivered by local non-specialist females under supervision. The primary outcome was individual psychological distress, measured by levels of anxiety and depression on the Hospital Anxiety and Depression Scale at 7th week after baseline. Secondary outcomes include symptoms of depression, post-traumatic stress disorder (PTSD), general psychological profile, levels of functioning and generalised psychological distress. Intervention acceptability was explored through in-depth interviews.
The results show that lay-helpers with no prior mental health experience can be trained to achieve the desired competency to successfully deliver the intervention in community settings under supervision. There was a good intervention uptake, with Group PM+ considered useful by participants, their families and lay-helpers. The outcome evaluation, which was not based on a large enough study to identify statistically significant results, indicated statistically significant improvements in depression, anxiety, general psychological profile and functioning. The PTSD symptoms and depressive disorder scores showed a trend in favour of the intervention.
This trial showed robust acceptance in the local settings with delivery by non-specialists under supervision by local trained females. The trial paves the way for further adaptation and exploration of the outcomes through larger-scale implementation and definitive randomised controlled trials in the local settings.
Background: Predicting epilepsy following a first seizure is difficult. Network abnormalities are observed in patients with epilepsy using resting-state functional MRI (rs-fMRI), which worsen with duration of epilepsy. We use rs-fMRI to identify network abnormalities in patients after a first seizure that can be used as a biomarker to predict development of epilepsy. Methods: Patients after a single, unprovoked seizure and age/sex matched healthy controls underwent 7 Tesla structural and resting-state functional MRI. Data were analyzed using graph theory measures. Patients were followed for development of epilepsy. Results: Nine patients and nine control subjects were analyzed. There were no differences in baseline characteristics. No patients developed epilepsy (average follow-up 3 months). No differences between groups occurred on a whole-brain network level. At a 20% threshold, significant differences occurred in the default mode network (DMN). Patients demonstrated an increased local efficiency (p=0.02) and clustering coefficient (p=0.04), and decreased path length (p=0.02) and betweenness centrality (p=0.02). Conclusions: No whole-brain network changes occur after a single unprovoked seizure. No patient has developed epilepsy suggesting this group does not have network alterations after a single seizure. In the DMN, the alterations noted indicate increased segregation of network function.
In 2014, over a million people were internally displaced after the launch of a military operation in North Waziristan, a tribal region on Pakistan's side of the Durand Line. Despite security concerns and restrictions, a collaborative mental health and psychosocial support initiative was undertaken in the district of Bannu. Monthly mental health camps were conducted for a period of 6 months by a multidisciplinary mental health team. The initiative also helped to assess mental health needs and plan training for primary care staff to strengthen existing resources.
As part of this initiative, Mental Health Gap Action Programme (mhGAP) training was conducted for physicians and psychosocial staff in the affected district. This marked the first instance of implementing these guidelines in Pakistan following a humanitarian crisis. This paper describes the training process including the adaptation of the mhGAP curriculum, training of trainers, training workshops for primary care staff and an analysis of results of pre- and post-testing of their knowledge about common mental disorders using a 25-item questionnaire.
The gaps in knowledge of primary care physicians in recognizing and managing common mental disorders were clearly identified. The mean pre- and post-test scores of the participants were 15.43, 62% (p value 0.000, s.d. 4.05) and 19.48, 78% (p value 0.000, s.d. 3.13) respectively, which showed significant improvement.
Despite the challenges of a humanitarian crisis, mhGAP guidelines can be successfully implemented to train primary care physicians in in low- and middle-income countries such as Pakistan. However, the dearth of primary care resources can hinder the complete integration of mental health services into primary healthcare.
Variation of the electric current profile as a means of energy release in a solar flare is investigated. In particular, the change in magnetic energy is calculated for some simple idealized cases of the current profile. It is suggested that current profile changes may explain the smallest observed energy release structures in a flare.
The height-integrated Pedersen and Hall conductivities are calculated for the weakly ionized region of the solar atmosphere in the vicinity of a sunspot. The values obtained are much larger than previous authors have estimated. Dynamo theories for solar flares which rely on the photospheric region having a large resistance are untenable.
A simple model for solar flares is described which invokes many ion-acoustic double layers in the source region. The ability of the model to explain some of the observed characteristics of solar flares is discussed, particular attention being paid to the well-observed high-energy flare examined by de Jager et al. (1987).
Children with obstructive sleep apnoea commonly undergo adenotonsillectomy as first-line surgical treatment. This paper aimed to investigate whether this intervention was associated with weight gain after surgery in the paediatric population with obstructive sleep apnoea.
Two independent researchers systematically reviewed the literature from 1995 to 2014 for studies on patients who underwent adenotonsillectomy with weight-based measurements before and after surgery. The databases used were Ovid Medline, Embase and PubMed.
Six papers satisfied all inclusion criteria. Four of these papers showed a significant weight increase and the others did not. The only high quality, randomised, controlled trial showed a significant increase of weight gain at seven months follow up, even in patients who were already overweight before their surgery.
The current evidence points towards an association between adenotonsillectomy and weight gain in patients with obstructive sleep apnoea in the short term.
A systematic review was performed to evaluate the role and effectiveness of head bandages after routine elective middle-ear surgery.
Studies that compared the effectiveness of head bandage use after elective middle-ear surgery (e.g. myringoplasty, mastoidectomy and cochlear implantation) were identified using the following databases: Ovid Medline and Embase, the Ebsco collections, the Cochrane Library, PubMed, and Google Scholar. An initial search identified 71 articles. All titles and abstracts were reviewed. Thirteen relevant articles were inspected in more detail; of these, only five met the inclusion criteria. These included three randomised, controlled trials, one retrospective case series and one literature review.
The three randomised, controlled trials (level of evidence 1b) showed no statistically significant differences in post-operative outcomes (in terms of complications) associated with head bandage use in middle-ear surgery. This finding was supported by the retrospective case series involving patients undergoing cochlear implantation.
Current available evidence shows no advantage of head bandage use after middle-ear surgery. Head bandages may not be required after routine, uncomplicated middle-ear surgery.
Background: The use of 3D endoscopy for posterior fossa surgery gradually adopted. In this study we compare the 3D to classic 2D endoscopy in evaluating neurovascular complexes in posterior fossa. Methods: Twenty retrosigmoid craniotomies, with a maximal diameter of 2cm were performed under neuronavigation on 10 fresh cadaveric heads. The posterior fossa dura matter was opened with a C-shaped incision and the base of the dural flap was placed over the sigmoid sinus. We used 3D and 2D endoscopes, with 0 and 45 degree angulations, connected to high definition camera lenses for optimal visualization of posterior fossa structures. Results: The superior, middle and inferior neurovascular complexes of the cerebellopontine angle were better visualized with 3D comparing to 2D endoscope. A detailed view of the porus trigeminous and structures associated with the tentorial incisura was also attained with 3D endoscopy. Conclusion: The high quality and resolution obtained by 3D endoscopy makes it a potentially valuable surgical and teaching tool in the armamentarium for endoscopic posterior fossa surgery. The stereoscopic view of the critical neurovascular structures of the posterior fossa, offered by 3D images, allows for a more detailed dissection in the difficult area of the cerebellopontine angle.
Genetically modified (GM) plants expressing Bt toxin provide protection against lepidopteran pests. The only GM crop in Pakistan is Bt cotton, which was illegally imported and adopted rapidly by cotton producers. Farmers gained access to the seed of many unapproved Bt genotypes before the matter was picked up and formal approval granted by the relevant governmental agencies. The present study was conducted to evaluate the samples of Bt cotton, collected from farmers and seed dealer, for transgene integration and expression. Seeds of 52 cotton genotypes, labelled as Bt, were collected from various farmers and seed dealers. An immunoblot strip test was carried out, which showed that only 0·86 of the samples collected were synthesizing Cry1Ac toxin. According to multiplexed polymerase chain reaction (PCR) results, 0·86 of the genotypes tested were positive for the Mon531 event (an ‘event’ is a specific genetic modification in a specific species) and 0·14 were negative for any transgene. Transcript analysis of transgenes in positive genotypes by real-time Rt-PCR confirmed the synthesis of mRNA in all genotypes but with significant variation. The concentration of Bt toxin revealed by enzyme linked immunosorbent assay (ELISA) showed that only 0·02 genotypes had the reported optimum level. The real-time PCR and ELISA results further confirmed the attenuation of transgene expression at transcriptional and translational level by various internal and external factors. The same type of event was found in all genotypes, with significant variation in toxin level, revealing the impact of genetic background on transgene expression. The findings support the recommendation to improve the existing quality criteria for transgenic cotton variety approval and certification in Pakistan, with the inclusion of toxin concentration in the list of parameters to be considered.
It is common practice to use head bandages for 7–10 days following pinnaplasty. However, head bandages are often troublesome for patients and can lead to serious complications.
A systematic review was performed to evaluate the use of head bandages after pinnaplasty. A search of Medline, Embase (Ovid) and CINAHL (EBSCO collections), the Cochrane Library, Pubmed (US National Library of Medicine) and Google Scholar identified 34 related articles. Of these, 14 were deemed relevant and 2 randomised controlled trials, 1 cohort study, 3 case series and 1 literature review met the inclusion criteria.
The two randomised controlled trials show no statistically significant difference in complications when a head bandage was used for the standard 7–10 days, for 24 hours or not at all. The three case series show that using a head bandage for 24 hours or not at all are safe alternatives. The review article recommended that when head bandages are applied after pinnaplasty it should be for the shortest duration possible.
Based on the available evidence, not using a head bandage at all or using one for a maximum of 24 hours following pinnaplasty is recommended.
The group-III nitrides have become versatile semiconductors for short wavelength emitters, high temperature microwave transistors, photodetectors, and field emission tips. The processing of these materials is significant due to the unusually high bond energies that they possess. The dry and wet etching methods developed for these materials over the last few years are reviewed. High etch rates and highly anisotropic profiles obtained by inductively-coupled-plasma reactive ion etching are presented. Photoenhanced wet etching provides an alternative path to obtaining high etch rates without ion-induced damage. This method is shown to be suitable for device fabrication as well as for the estimation of dislocation densities in n-GaN. This has the potential of developing into a method for rapid evaluation of materials.
Ti/Pt/Au metallization on p-type GaN/AlxGa1−xN (x=0.10 and 0.20) superlattices (SL) were investigated as ohmic contacts. Current-voltage and specific contact resistance measurements indicate enhanced p-type doping in the superlattice structures compared to that in GaN. Ti/Pt/Au is shown to be an effective ohmic metallization scheme on p-type GaN/AlxGa1−xN superlattices. A specific contact resistance of Rc = 4.6×10−4 ω-cm2 is achieved for unalloyed Ti/Pt/Au on GaN/Al0.2Ga0.8N SL. This is reduced to 1.3×10−4 ω-cm2 after annealing for 5 minutes at 300 °C.
A study on light absorption enhancement of an InAs quantum dots embedded into InxGa1-xAs quantum well with GaAs as a barrier solar cells was carried out. Solar cell devices were fabricated from different structures, which were grown by using molecular beam epitaxy, with the In mole fraction (x) varied between 0 – 25 %. Poly-L-Lysine ligands and ZnO sol-gel was used to modify the surface of the solar cells and act as anti-reflection coatings. The anti-reflection characteristic of the ligands and the sol-gel were investigated by measuring the solar cell characteristics before and after the solar cells surface modifications. The current-voltage characteristics were measured of the fabricated solar cells before and after Poly-L-Lysine and ZnO coatings. A significant enhancement on the order of 40 % of the solar cells performance was observed. This type of enhancement was observed in the power conversion efficiency, spectral response measurements, and external quantum efficiency.