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Heating coils utilize the concept of resistive heating to convert electrical energy into thermal energy. Uniform heating of the target area is the key performance indicator for heating coil design. Highly uniform distribution of temperature can be achieved by using a dense metal distribution in the area under consideration, however, this increases the cost of production significantly. A low-cost and efficient heating coil should have excellent temperature uniformity while having minimum metal consumption. In this work, space-filling fractal curves, such as Peano curve, Hilbert curve and Moore curve of various orders, have been studied as geometries for heating coils. In order to compare them in an effective way, the area of the geometries has been held constant at 30 mm × 30 mm and a constant power of 2 W has been maintained across all the geometries. Further, the thickness of the metal coils and their widths have been kept constant for all geometries. Finite Element Analysis (FEA) results show Hilbert and Moore curves of order-4, and Peano curve of order-3 outperform the typical double-spiral heater in terms of temperature uniformity and metal coil length.
This paper considers actuator redundancy management for a redundant multirotor Unmanned Aerial Vehicle (UAV) under actuators failures. Different approaches are proposed: using robust control (passive fault tolerance), and reconfigurable control (active fault tolerance). The robust controller is designed using high-order super-twisting sliding mode techniques, and handles the failures without requiring information from a Fault Detection scheme. The Active Fault-Tolerant Control (AFTC) is achieved through redistributing the control signals among the healthy actuators using reconfigurable multiplexing and pseudo-inverse control allocation. The Fault Detection and Isolation problem is also considered by proposing model-based and model-free modules. The proposed techniques are all implemented on a coaxial octorotor UAV. Different experiments with different scenarios were conducted for the validation of the proposed strategies. Finally, advantages, disadvantages, application considerations and limitations of each method are examined through quantitative and qualitative studies.
There are several agents used for conscious sedation by various routes in children. The aim of this prospective randomised study is to compare the effectiveness of three commonly used sedatives: intranasal ketamine, intranasal midazolam, and oral chloral hydrate for children undergoing transthoracic echocardiography.
Children who were referred to paediatric cardiology due to a heart murmur for transthoracic echocardiography were prospectively randomised into three groups. Seventy-three children received intranasal midazolam (0.2 mg/kg), 72 children received intranasal ketamine (4 mg/kg), and 72 children received oral chloral hydrate (50 mg/kg) for conscious sedation. The effects of three agents were evaluated in terms of intensity, onset, and duration of sedation. Obtaining high-quality transthoracic echocardiography images (i.e. absence of artefacts) were regarded as successful sedation. Side effects due to medications were also noted.
There was no statistical difference in terms of sedation success rates between three groups (95.9, 95.9, and 94.5%, respectively). The median onset of sedation in the midazolam, ketamine, and chloral hydrate was 14 minutes (range 7–65), 34 minutes (range 12–56), and 40 minutes (range 25–57), respectively (p < 0.001 for all). However, the median duration of sedation in study groups was 68 minutes (range 20–75), 55 minutes (range 25–75), and 61 minutes (range 34–78), respectively (p = 0.023, 0.712, and 0.045). Gastrointestinal side effects such as nausea and vomiting were significantly higher in the chloral hydrate group (11.7 versus 0% for midazolam and 2.8% for ketamine, respectively, p = 0.002).
Results of our prospectively randomised study indicate that all three agents provide adequate sedation for successful transthoracic echocardiography. When compared the three sedatives, intranasal midazolam has a more rapid onset of sedation while intranasal ketamine has a shorter duration of sedation. Intranasal ketamine can be used safely with fewer side effects in children undergoing transthoracic echocardiography.
The Hkakabo Razi region located in northern Myanmar is an Important Bird Area and part of the Eastern Himalayan Biodiversity Hotspot. Within the framework of the World Heritage Convention to enlist the site under criterion (ix) and (x), we conducted a biodiversity assessment for passerine birds using DNA barcoding and other molecular markers. Of the 441 bird species recorded, we chose 16 target species for a comparative phylogeographic study. Genetic analysis was performed for a larger number of species and helped identifying misidentified species. We found phylogeographic structure in all but one of the 16 study species. In 13 species, populations from northern Myanmar were genetically distinctive and local mitochondrial lineages differed from those found in adjacent regions by 3.9–9.9% uncorrected genetic distances (cytochrome-b). Since the genetic distinctiveness of study populations will be corroborated by further differences in morphology and song as in other South-East Asian passerines, many of them will be candidates for taxonomic splits, or in case an older taxon name is not available, for the scientific description of new taxa. Considering the short time frame of our study we predict that a great part of undetected faunal diversity in the Hkakabo Razi region will be discovered.
This paper deals with the problem of fault-tolerant control (FTC) for redundant multirotor unmanned aerial vehicles (UAVs) subject to actuators failures. A fuzzy logic approach is used to solve the constrained control allocation problem by adjusting the components of the multiplexing vector once a motor failure is detected. This fuzzy logic allocation problem is tuned using the Bacterial Foraging Algorithm (BFA), a powerful bio-inspired optimisation technique. The effectiveness of this approach is illustrated through real experimental application to a hexarotor UAV, where up to two motors failures are considered.
The 2008 economic recession was associated with an increase in suicide internationally. Studies have focused on the impact in the general population with little consideration of the effect on people with a mental illness.
To investigate suicide trends related to the recession in mental health patients in England.
Using regression models, we studied suicide trends in mental health patients in England before, during and after the recession and examined the demographic and clinical characteristics of the patients. We used data from the National Confidential Inquiry into Suicide and Safety in Mental Health, a national data-set of all suicide deaths in the UK that includes detailed clinical information on those seen by services in the last 12 months before death.
Between 2000 and 2016, there were 21 224 suicide deaths by patients aged 16 or over. For male patients, following a steady fall of 0.5% per quarter before the recession (quarterly percent change (QPC) 2000–2009 –0.46%, 95% CI –0.66 to –0.27), suicide rates showed an upward trend during the recession (QPC 2009–2011 2.37%, 95% CI –0.22 to 5.04). Recession-related rises in suicide were found in men aged 45–54 years, those who were unemployed or had a diagnosis of substance dependence/misuse. Between 2012 and 2016 there was a decrease in suicide in male patients despite an increasing number of patients treated. No significant recession-related trends were found in women.
Recession-associated increases in suicide were seen in male mental health patients as well as the male general population, with those in mid-life at particular risk. Support and targeted interventions for patients with financial difficulties may help reduce the risk at times of economic hardship. Factors such as drug and alcohol misuse also need to be considered. Recent decreases in suicide may be related to an improved economic context or better mental healthcare.
Declaration of interest
N.K. is supported by Greater Manchester Mental Health NHS Foundation Trust. L.A. chairs the National Suicide Prevention Strategy Advisory Group at the Department of Health (of which N.K. is also a member) and is a non-executive Director for the Care Quality Commission. N.K. chairs the National Institute for Health and Care Excellence (NICE) depression in adults guideline and was a topic expert member for the NICE suicide prevention guideline.
Introduction: Procedural skills training varies significantly across Canadian medical schools, and there is currently no standardized assessment tool to evaluate its benefits. This project aims to develop a curriculum that teaches 2nd-year medical students to perform and evaluate procedural skills. The goals of this program include decreasing anxiety, increasing confidence, and achieving competence for students and also allowing staff to judge the appropriate level of supervision when delegating learners to perform basic procedures in the team setting. Our curriculum incorporates, near-peer teaching as well as near peer formative assessment. Methods: Each of the twelve 2nd year participants completed a State Trait Anxiety Inventory and self-reported confidence questionnaire related to procedural skills. Students participated in four sessions taught by expert physicians over a five month period. A new skill was taught at each monthly workshop and an opportunity to practice previously taught skills was provided. Skills were assessed in a skills integration simulation OSCE, and the anxiety and confidence questionnaire was repeated. Results: Students who completed this pilot program showed a significant decrease in mean anxiety state (2.48 vs 1.74, p-value <0.001), while the control group did not (p-value = 0.408). When assessing confidence, students who completed this program showed increased self-assessed knowledge and confidence in each of the program's assessed skills. An increased level of competency was achieved in each skill by each student as assessed by the expert physicians. Conclusion: There is evidence to suggest that implementation of this procedural skills training model within the Canadian medical school curriculum may improve student anxiety, confidence, and competency for success in clerkship and could be the foundation for developing milestones for EPAs.
Introduction: In order to better characterize procedural skills curricula in Canada, a national survey was conducted. The objectives of the survey were: (i) to characterize procedural skills education currently employed in pre-clerkship and clerkship curricula; (ii) to determine what skills physician-educators think medical students should know upon graduation; and (iii) to identify physician-educator perceptions regarding the development of pre-clerkship procedural curriculum. Methods: A web-based survey was distributed to 201 clinician-educators across Canada's 17 medical schools. Respondents were directed to an individualized survey based on their self-identified roles at their institution. Respondents were asked demographic questions, what procedural skills are being taught and in what setting at their institution, and their opinions on the value of a pre-clerkship procedural curriculum. Results: From the 17 school's surveyed, 12 schools responded, with 8 schools responding “yes” that they had a clerkship procedural curriculum. For a pre-clerkship procedural curriculum, only 4 schools responded “yes”. The 5 of the top 10 procedurals skills identified that medical students should know upon graduation, in order, are: IV Access, Airway Management/Ventilator Management, Local anesthesia/field block, Casting, Spontaneous Vaginal Delivery. On a Likert scale, clinician-educators strongly supported a pre-clerkship procedural curriculum (median = 4.00/5.00, mode = 5.00/5.00), and they believed it would decrease anxiety (median = 4.00/5.00), increase confidence (median = 4.00/5.00), and increase technical ability (median = 3.00/5.00) in incoming clerks. Conclusion: Across Canada, the state of undergraduate medical education procedural skills education is inconsistent. With the identification of the Top 10 procedural skills medical students should know upon graduation, the learning objectives of a formal curriculum can be developed. With overwhelming support from physician-educators, a formal pre-clerkship procedural curriculum is poised to redefine the landscape of procedural care for a whole new generation of physicians.
To investigate the expression of basic fibroblast growth factor in the matrix of human acquired cholesteatoma compared to the deep meatal skin. This topic does not appear to have been fully investigated before.
An immunochemical study was conducted. Cholesteatoma tissues from adult patients were collected during surgery (n = 19). Control specimens were taken from the deep meatal skin (n = 8) and compared.
A highly significant difference in basic fibroblast growth factor expression was identified between cholesteatoma and skin (mean ± standard error = 58.53 ± 3.6 per cent in cholesteatoma vs 40.6 ± 3.5 per cent in skin; p = 0.005). Both basal and parabasal keratinocytes were stained positive with basic fibroblast growth factor. Additionally, there was specific staining in the basal columnar middle-ear epithelium and mast cell membrane.
Basic fibroblast growth factor plays an active role in proliferative activity of cholesteatoma through its overexpression in basal and parabasal layers of cholesteatoma matrix. Moreover, its expression in the mast cell membrane supports its role in bone resorption activity.
Recent discoveries of multicomponent concentrated solid-solution alloys hold promise for enhanced properties—such as enhanced mechanical properties, radiation tolerance, high temperature strength, corrosion resistance and some novel functional properties, provide a new strategy for alloy design using extreme disorder. Yet, deep understanding of these intriguing properties is complicated by the very effects of disorder that make them interesting. All the desirable properties of these alloys ultimately originate from the disorder-induced properties of underlying electronic structure, lattice dynamics, and thermodynamics. Therefore, understanding the disorder-induced fundamental physical properties is prerequisite for the science-based design of this class of alloys for practical applications. Here, we elucidate the role of extreme (maximal) substitutional disorder plays in the fundamental physics of disordered alloys and review the recently developed theoretical methodologies in modeling the basic physical properties, particularly electronic structure, magnetism, electrical transport, and lattice vibrations in multicomponent concentrated solid-solution alloys.
Short bowel syndrome (SBS) represents a serious intestinal absorption disorder, and patients may be prone to severe malnutrition. Dietetic therapy is critically important both for immediate prognosis and successful long-term rehabilitation. To maintain energy balance, an accurate assessment of energy intake is required. Our objective was to compare energy intake (EI) assessed by 24-h dietary recalls (EIrecall), a standard clinical assessment, with the total energy expenditure measured by the doubly labelled water (TEEdlw) method in SBS patients and matched controls. A total of twenty-two participants (eleven each in the SBS and control groups (CG), six female and five male) were evaluated; CG were matched to SBS patients on the basis of age, BMI and sex. TEE was measured by DLW and compared with EI determined by four 24-h dietary recalls using the USDA Automated Multiple-Pass Method. Bland–Altman plots and paired Student’s t test were used to compare EIrecall with TEEdlw (P<0·05). Participants’ mean age was 53 (sd 8) years. TEEdlw (7·85 (SD 1·16) MJ/d, 0·14 (SD 0·02) MJ/kg per d) was significantly lower (P=0·014) compared with EIrecall (11·07 (SD 3·45) MJ/d, 0·21 (SD 0·08) MJ/kg per d) in the SBS group. On the other hand, in the CG group TEEdlw (10·02 (SD 1·86) MJ/d, 0·18 (SD 0·03) MJ/kg per d) was significantly higher (P=0·001) compared with EIrecall (7·19 (SD 1·68) MJ/d, 0·13 (SD 0·03) MJ/kg per d). In SBS patients, reported EI is higher than DLW-measured EI. Therefore, providing or prescribing energetic intake based on EIrecall without accounting for potential malabsorption-related losses can compromise the energy needs in SBS patients and affect nutritional status in the long term.
Spilonota ocellana (Denis and Schiffermüller) (Lepidoptera: Tortricidae) can be a serious pest of organic apples (Malus domestica Borkhausen (Rosaceae)) in British Columbia, Canada. Recent discovery that S. ocellana moths are attracted by a lure combining acetic acid (AA) and benzyl nitrile (BN), identified as a caterpillar-induced apple leaf volatile, provides an opportunity to develop bisexual mass-trapping or monitoring systems. Sticky white delta traps baited with benzyl nitrile (10 mg/red rubber septum) and an acetic-acid co-lure (3 mL AA/3-mm open 8-mL vial) caught significantly more moths than either component alone. Acetic-acid co-lures were weakly attractive but benzyl-nitrile-loaded septa were not attractive. Moth catches with AA+BN lures were unaffected by the size and type of rubber septum used to release benzyl nitrile, but catches increased with increasing loads of benzyl nitrile. Male and total moth catches were maximised using membrane release devices loaded with a mixture of benzyl nitrile and a second caterpillar-induced volatile, 2-phenylethanol (PET), in combination with an acetic-acid co-lure (AA+BN-PET). Female catches with AA+BN-PET and AA+BN lures were equivalent. Placing AA+BN lures in traps baited with female sex pheromone lures reduced male catches, but female catches were unchanged. When sticky liners were replaced weekly, white delta traps baited with AA+BN lures caught more moths than similarly baited white Multipher®-I bucket traps, or transparent UnitrapsTM. Multipher-I traps with a propylene glycol killing agent (250 mL) caught more moths than those with Vapona insecticide strips. In apple orchards treated with mating disruption sex pheromones, traps baited with AA+BN caught slightly more total moths than traps baited with sex pheromone. Weekly, total male+female moth catches with either AA+BN or sex pheromone lures showed similar seasonal patterns in both untreated and pheromone-disrupted orchards, respectively. Long-lasting release devices and an organic killing agent are needed to develop certified organic mass-trapping technologies for management of S. ocellana with the AA+BN kairomone.
Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) is one of several leaf-feeding caterpillar pests of commercial tree-fruit crops in British Columbia, Canada. Recent discovery that European Pandemis Hübner species are attracted by lures combining acetic acid and the caterpillar-induced apple-leaf volatiles, 2-phenylethanol, and phenylacetonitrile, prompted our examination of P. limitata response to these compounds. Trapping tests in organic apple orchards revealed that neither of these individual benzenoids, nor their binary combination, was attractive. Acetic acid alone was weakly attractive, but more importantly, catches increased significantly when an acetic-acid co-lure was combined with 2-phenylethanol or phenylacetonitrile, individually and together. Catches of male and female P. limitata with acetic acid+2-phenylethanol, or acetic acid+2-phenylethanol+phenylacetonitrile were similar, respectively, and both sexes were caught significantly less often in traps baited with acetic acid+phenylacetonitrile. When combined with acetic-acid co-lures, traps baited with membrane dispensers releasing 2-phenylethanol at ~1 mg/day caught significantly more moths than traps baited with rubber septa lures releasing 2-phenylethanol at ~0.6 mg/day. Moth catches in traps baited with 2-phenylethanol were unaffected when the emission of acetic-acid co-lures was increased from ~28 to 63 mg/day. Catches of male P. limitata in traps baited with sex pheromone were significantly greater than catches in traps baited with acetic acid+2-phenylethanol, or traps baited with a ternary blend of acetic acid+2-phenylethanol+sex pheromone. Catches of female P. limitata in traps baited with acetic acid+2-phenylethanol were significantly reduced when it was combined with sex pheromone. Use of the ternary acetic acid+2-phenylethanol+phenylacetonitrile blend provides an opportunity to develop multispecies bisexual trapping systems to improve management of sympatric tortricid pests currently causing economic losses in organic apples in British Columbia. More work on long-lasting release devices, nonsaturating traps, and organically acceptable killing agents are needed to develop organic mass-trapping systems.
Patients admitted to hospital at the weekend appear to be at increased risk of death compared with those admitted at other times. However, a ‘weekend effect’ has rarely been explored in mental health and there may also be other times of year when patients are vulnerable.
To investigate the timing of suicide in high-risk mental health patients.
We compared the incidence of suicide at the weekend v. during the week, and also in August (the month of junior doctor changeover) v. other months in in-patients, patients within 3 months of discharge and patients under the care of crisis resolution home treatment (CRHT) teams (2001–2013).
The incidence of suicide was lower at the weekends for each group (incidence rate ratio (IRR) = 0.88 (95% CI 0.79–0.99) for in-patients, IRR = 0.85 (95% CI 0.78–0.92) for post-discharge patients, IRR = 0.87 (95% CI 0.78–0.97) for CRHT patients). Patients who died by suicide were also less likely to have been admitted at weekends than during the week (IRR = 0.52 (95% CI 0.45–0.60)). The incidence of suicide in August was not significantly different from other months.
We found evidence of a weekend effect for suicide risk among high-risk mental health patients, but with a 12–15% lower incidence at weekends. Our study does not support the claim that safety is compromised at weekends, at least in mental health services.
Background: Coronary artery lesions in Kawasaki disease invasively assessed by coronary angiography. Evaluation of myocardial perfusion by single-photon emission computed tomography may identify the haemodynamic significance of coronary lesions. Objective: To evaluate diagnostic accuracy of dipyridamole stress technetium-99 m tetrofosmin, single-photon emission computed tomography as a possible alternative to invasive coronary angiography for detection and follow-up of myocardial ischaemia in patients with Kawasaki disease, and pre- and post-coronary bypass grafting. Patients and methods: Coronary angiography and single-photon emission computed tomography were performed on 21 patients who were classified into three groups – group I (stenosis), group II (giant aneurysms), and group III (small aneurysms). Of the 21 patients, 16 (groups I and II) patients with myocardial perfusion defects, who underwent coronary bypass grafting, were followed up with single-photon emission computed tomography. Result: In group I, all patients had significant coronary stenosis and 100% of them had perfusion defects in the anterior and septal walls. In group II, all patients had giant aneurysms and 83% of them had inferior and inferolateral perfusion defects. In group III, all patients had small aneurysms and 100% of them had normal perfusion. Pre-coronary bypass grafting myocardial ischaemic defects disappeared in all patients after surgery. Sensitivity, specificity, and accuracy of single-photon emission computed tomography were 94, 100, and 95%, respectively. Conclusion: Technetium-99 m tetrofosmin single-photon emission computed tomography can be applied as an accurate non-invasive diagnostic technique for detecting myocardial perfusion defects with coronary artery lesions, and to show improved or even normalised perfusion of the myocardium in patients after surgical revascularisation.
A nonlinear stability of two superposed semi-infinite Walters B′ viscoelastic dielectric fluids streaming through porous media in the presence of vertical electric fields in absence of surface charges at their interface is investigated in three dimensions. The method of multiple scales is used to obtain a Ginzburg-Landau equation with complex coefficients describing the behavior of the system. The stability of the system is discussed both analytically and numerically in linear and nonlinear cases, and the corresponding stability conditions are obtained. It is found, in the linear case, that the surface tension and medium permeability have stabilizing effects, and the fluid velocities, electric fields and kinematic viscoelastici-ties have destabilizing effects, while the porosity of porous medium and kinematic viscosities have dual role on the stability. In the nonlinear case, it is found that the fluid velocities, kinematic viscosities, kinematic viscoelasticities, surface tension and porosity of porous medium have stabilizing effects; while the electric fields and medium permeability have destabilizing effects.
In this paper, we studied the peristaltic flow and heat transfer of an incompressible, electrically conducting Bingham Non-Newtonian fluid in an eccentric uniform annulus in the presence of external uniform magnetic field with slip velocity and temperature jump at the wall conditions. The viscous and Joule dissipations are taken into account. The inner tube is rigid and moving with a constant axial velocity, while the outer tube has a sinusoidal wave traveling down its wall. Under zero Reynolds number condition with the long wavelength approximation, the axial velocity and the stream function are obtained analytically. A numerical solution for the governing partial differential equation of energy is performed in order to analyze the temperature distribution. The effects of all parameters of the problem are numerically discussed and graphically explained.