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Camber morphing is an effective way to control the lift generated by any aerofoil and potentially improve the range (as measured by the lift-to-drag ratio) and endurance (as measured by
). This can be especially useful for fixed-wing Unmanned Aerial Vehicles (UAVs) undergoing different flying manoeuvres and flight phases. This work investigates the aerodynamic characteristics of the NACA0012 aerofoil morphed using a Single Corrugated Variable-Camber (SCVC) morphing approach. Structural analysis and morphed shapes are obtained based on small-deformation beam theory using chain calculations and validated using finite-element software. The aerofoil is then reconstructed from the camber line using a Radial Basis Function (RBF)-based interpolation method (J.H.S. Fincham and M.I. Friswell, “Aerodynamic optimisation of a camber morphing aerofoil,” Aerosp. Sci. Technol., 2015). The aerodynamic analysis is done by employing two different finite-volume solvers (OpenFOAM and ANSYS-Fluent) and a panel method code (XFoil). Results reveal that the aerodynamic coefficients predicted by the two finite-volume solvers using a fully turbulent flow assumption are similar but differ from those predicted by XFoil. The aerodynamic efficiency and endurance factor of morphed aerofoils indicate that morphing is beneficial at moderate to high lift requirements. Further, the optimal morphing angle increases with an increase in the required lift. Finally, it is observed for a fixed angle-of-attack that an optimum morphing angle exists for which the aerodynamic efficiency becomes maximum.
Background: Since January 1, 2016 2358 people have died from opioid poisoning in Alberta. Buprenorphine/naloxone (bup/nal) is the recommended first line treatment for opioid use disorder (OUD) and this treatment can be initiated in emergency departments and urgent care centres (EDs). Aim Statement: This project aims to spread a quality improvement intervention to all 107 adult EDs in Alberta by March 31, 2020. The intervention supports clinicians to initiate bup/nal for eligible individuals and provide rapid referrals to OUD treatment clinics. Measures & Design: Local ED teams were identified (administrators, clinical nurse educators, physicians and, where available, pharmacists and social workers). Local teams were supported by a provincial project team (project manager, consultant, and five physician leads) through a multi-faceted implementation process using provincial order sets, clinician education products, and patient-facing information. We used administrative ED and pharmacy data to track the number of visits where bup/nal was given in ED, and whether discharged patients continued to fill any opioid agonist treatment (OAT) prescription 30 days after their index ED visit. OUD clinics reported the number of referrals received from EDs and the number attending their first appointment. Patient safety event reports were tracked to identify any unintended negative impacts. Evaluation/Results: We report data from May 15, 2018 (program start) to September 31, 2019. Forty-nine EDs (46% of 107) implemented the program and 22 (45% of 49) reported evaluation data. There were 5385 opioid-related visits to reporting ED sites after program adoption. Bup/nal was given during 832 ED visits (663 unique patients): 7 visits in the 1st quarter the program operated, 55 in the 2nd, 74 in the 3rd, 143 in the 4th, 294 in the 5th, and 255 in the 6th. Among 505 unique discharged patients with 30 day follow up data available 319 (63%) continued to fill any OAT prescription after receiving bup/nal in ED. 16 (70%) of 23 community clinics provided data. EDs referred patients to these clinics 440 times, and 236 referrals (54%) attended their first follow-up appointment. Available data may under-report program impact. 5 patient safety events have been reported, with no harm or minimal harm to the patient. Discussion/Impact: Results demonstrate effective spread and uptake of a standardized provincial ED based early medical intervention program for patients who live with OUD.
Field experiments were carried out in order to investigate if brown manuring (BM) using Sesbania plants can be used to control weeds in maize, especially Cyperus rotundus (Experiment I), and further to optimize the BM technology through appropriate Sesbania seed rate (S), 2,4-D application time (T) and dose (D) (Experiment II). Each BM treatment received a pre-emergence application of pendimethalin 1.0 kg a.i./ha. Experiment I showed that the BM practice using 15 kg/ha Sesbania seed and 2,4-D 0.50 kg a.i./ha applied at 25 DAS led to better control of weeds, especially C. rotundus and higher maize grain yield. Further optimization studies (Experiment II) indicated that among the factors S, T and D, the BM combination S~25 kg/ha, D~0.50 kg a.i./ha and T~25 DAS (i.e. S25T25D0.50) resulted in lowest weed density (3.1/m2) and dry weight (3.8 g/m2) and highest weed control index (89.2%) at 60 days after sowing (DAS) which was at par with another BM practice S15T25D0.50. However, the later BM combination led to significantly higher maize productivity (5.25 t/ha) and profitability (net returns (NR) $878/ha), which were 103 and 280% higher, respectively, than the weedy check (WC). The Sesbania seed rate S~15 kg/ha gave 7% higher maize grain yield and 12% higher NR than its corresponding level S~25 kg/ha. Therefore, Sesbania BM with 15 kg seeds/ha and 2,4-D at 0.50 kg a.i/ha applied at 25 DAS can be recommended for effective and eco-friendly weed management in maize, which would provide higher maize grain yield and enhance farmers' profitability.
Background: Buprenorphine/naloxone (bup/nal) is a partial opioid agonist/antagonist and recommended first line treatment for opioid use disorder (OUD). Emergency departments (EDs) are a key point of contact with the healthcare system for patients living with OUD. Aim Statement: We implemented a multi-disciplinary quality improvement project to screen patients for OUD, initiate bup/nal for eligible individuals, and provide rapid next business day walk-in referrals to addiction clinics in the community. Measures & Design: From May to September 2018, our team worked with three ED sites and three addiction clinics to pilot the program. Implementation involved alignment with regulatory requirements, physician education, coordination with pharmacy to ensure in-ED medication access, and nurse education. The project is supported by a full-time project manager, data analyst, operations leaders, physician champions, provincial pharmacy, and the Emergency Strategic Clinical Network leadership team. For our pilot, our evaluation objective was to determine the degree to which our initiation and referral pathway was being utilized. We used administrative data to track the number of patients given bup/nal in ED, their demographics and whether they continued to fill bup/nal prescriptions 30 days after their ED visit. Addiction clinics reported both the number of patients referred to them and the number of patients attending their referral. Evaluation/Results: Administrative data shows 568 opioid-related visits to ED pilot sites during the pilot phase. Bup/nal was given to 60 unique patients in the ED during 66 unique visits. There were 32 (53%) male patients and 28 (47%) female patients. Median patient age was 34 (range: 21 to 79). ED visits where bup/nal was given had a median length of stay of 6 hours 57 minutes (IQR: 6 hours 20 minutes) and Canadian Triage Acuity Scores as follows: Level 1 – 1 (2%), Level 2 – 21 (32%), Level 3 – 32 (48%), Level 4 – 11 (17%), Level 5 – 1 (2%). 51 (77%) of these visits led to discharge. 24 (47%) discharged patients given bup/nal in ED continued to fill bup/nal prescriptions 30 days after their index ED visit. EDs also referred 37 patients with OUD to the 3 community clinics, and 16 of those individuals (43%) attended their first follow-up appointment. Discussion/Impact: Our pilot project demonstrates that with dedicated resources and broad institutional support, ED patients with OUD can be appropriately initiated on bup/nal and referred to community care.
Dust vortices with a void at the centre are reported in this paper. The role of the spatial variation of the plasma potential in the rotation of dust particles is studied in a parallel plate glow discharge plasma. Probe measurements reveal the existence of a local potential minimum in the region of formation of the dust vortex. The minimum in the potential well attracts positively charged ions, while it repels the negatively charged dust particles. Dust rotation is caused by the interplay of the two oppositely directed ion drag and Coulomb forces. The balance between these two forces is found to play a major role in the radial confinement of the dust particles above the cathode surface. Evolution of the dust vortex is studied by increasing the discharge current from 15 to 20 mA. The local minimum of the potential profile is found to coincide with the location of the dust vortex for both values of discharge currents. Additionally, it is found that the size of the dust vortex as well as the void at the centre increases with the discharge current.
Measurements of local plasma parameters in dusty plasma are crucial for understanding
the physics issues related to such systems. The Langmuir probe, a small electrode
immersed in the plasma, provides such measurements. However, designing of a Langmuir
probe system in a dusty plasma environment demands special consideration. First, the
probe has to be miniaturized enough so that its perturbation on the ambient dust
structure is minimal. At the same time, the probe dimensions must be such that a
well-defined theory exists for interpretation of its characteristics. The associated
instrumentation must also support the measurement of current collected by the probe
with high signal to noise ratio. The most important consideration, of course, comes
from the fact that the probes are prone to dust contamination, as the dust particles
tend to stick to the probe surface and alter the current collecting area in
unpredictable ways. This article describes the design and operation of a Langmuir
probe system that resolves these challenging issues in dusty plasma. In doing so,
first, different theories that are used to interpret the probe characteristics in
collisionless as well as in collisional regimes are discussed, with special emphasis
on application. The critical issues associated with the current–voltage
characteristics of Langmuir probe obtained in different operating regimes are
discussed. Then, an algorithm for processing these characteristics efficiently in
presence of ion-neutral collisions in the probe sheath is presented.
This study aimed to develop a functional model of subglottic stenosis by inducing direct airway irritation in transplanted mouse laryngotracheal complexes.
Laryngotracheal complexes from C57BL/6 mice were harvested and divided into three groups: uninjured, mechanically injured and chemically injured. Donor laryngotracheal complexes from each group were placed in dorsal subcutaneous pockets of recipient mice. Each week, the transplanted laryngotracheal complexes were harvested, and tissues were fixed, sectioned, and stained with haematoxylin and eosin. Representative slides were reviewed by a blinded pathologist, to determine the formation of granulation tissue, and graded as to the degree of granulation formation.
Direct airway irritation induced granulation tissue formation under the disrupted epithelium of airway mucosa; this was seen as early as two weeks after chemical injury.
Results indicate that granulation tissue formation in a murine model may be an efficient tool for investigating the development and treatment of subglottic stenosis.
In a quasineutral plasma, electrons undergo collective oscillations, known as plasma oscillations, when perturbed locally. The oscillations propagate due to finite temperature effects. However, the wave can lose the phase coherence between constituting oscillators in an inhomogeneous plasma (phase mixing) because of the dependence of plasma oscillation frequency on plasma density. The longitudinal electric field associated with the wave may be used to accelerate electrons to high energies by exciting large amplitude wave. However when the maximum amplitude of the wave is reached that plasma can sustain, the wave breaks. The phenomena of wave breaking and phase mixing have applications in plasma heating and particle acceleration. For detailed experimental investigation of these phenomena a new device, inverse mirror plasma experimental device (IMPED), has been designed and fabricated. The detailed considerations taken before designing the device, so that different aspects of these phenomena can be studied in a controlled manner, are described. Specifications of different components of the IMPED machine and their flexibility aspects in upgrading, if necessary, are discussed. Initial results meeting the prerequisite condition of the plasma for such study, such as a quiescent, collisionless and uniform plasma, are presented. The machine produces δnnoise/n ⩽ 1%, Luniform ~ 120 cm at argon filling pressure of ~10−4 mbar and axial magnetic field of B = 1090 G.
The north eastern region (NER) of India receives a high amount of rainfall (2450 mm) both in terms of intensity and frequency. Most of the precipitation goes waste because of improper conservation measures and inadequate rainwater harvesting. Growing a second crop during winter (rabi) season on hill slopes and uplands without moisture conservation measure is almost impossible. A simple and very low-cost technique of in situ soil moisture conservation in maize (Zea mays L.)–toria (Brassica campestris L.) system has been developed using residue of preceding rainy season maize crop and mulching with locally available weed biomass Ambrosia artemisiifolia. Six residue mulching combinations tested were viz. control, Maize stalk cover (MSC), MSC + Ambrosia sp. 5 t/ha, MSC + Ambrosia sp. 10 t/ha, MSC + farmyard manure (FYM) 10 t/ha and MSC + Ambrosia sp. 5 t/ha + poultry manure 5 t/ha under zero tillage (ZT) and conventional tillage (CT) systems. Results showed that in situ residue retention of preceding maize crop along with green biomass of Ambrosia sp., applied before sowing of toria, maintained optimum soil moisture for good growth and higher yield of toria. The soil moisture content was consistently higher under residue mulched plots than that under control. All the residue mulching measures recorded higher crop yield for maize and toria than those observed under residue removal (control). The productivity of toria was enhanced by about 99%, only due to retention of MSC as mulch. Mulching with MSC + Ambrosia sp. 5 t/ha + poultry manure 5 t/ha recorded the highest seed yield of toria (four-year average: 641 kg/ha), which was 228% and 64% higher than no mulching (control) and MSC alone. MSC + FYM 10 t/ha (568.3 t/ha) and MSC + Ambrosia sp. 10 t/ha (517.4 t/ha) were found equally effective and produced significantly higher toria yield than that of control. MSC + Ambrosia mulch 10 t/ha gave the highest net returns and B:C ratio of the maize–toria system. The overall B:C ratios were better under ZT than CT. Thus, the study indicated that the integrated management of crop residues and weed biomass (Ambrosia sp.) under ZT created favourable soil moisture to support double cropping with high yield in hill eco-system of northeastern Indian Himalayas.
The OVV blazar 3C 446 was monitored over seven months in 1997 with ground based telescopes and instruments on ESA's Infrared Space Observatory (ISO). The aim was to try to detect variations in the IR and see if these were correlated with optical variations. The object varied in the optical and near-IR during this period, but did not vary in the far-IR. Despite being a factor of ten weaker than in 1983, the optical-IR SED exhibited the same slope. The new far-IR observations from ISO allow us to determine the location of the turnover in the spectrum, caused by synchrotron self-absorption. It occurs just longwards of 100 μm.
Continuous cultivation of rice–wheat cropping system in the Indo-Gangetic plains is under threat with decline in soil organic carbon (SOC), total factor productivity and overall sustainability. Pulses, an important component of crop diversification, are known to improve soil quality through their unique ability of biological N2 fixation, leaf litter fall and deep root system. Therefore, the effect of inclusion of pulses in the puddled rice system under organic and inorganic amendments on SOC pool and its management indices were evaluated in a long-term experiment after seven cropping cycles. The results indicated that inclusion of pulses in the rice-based system improved the SOC content, being greater in surface soil (0–20 cm) and declining with soil depth. Among the four carbon fractions determined, less labile carbon fraction (Cfrac3) was the dominant fraction in the puddled rice system, particularly under organic treatments, indicating that it is possible to maintain organic carbon for longer time in this system. The rice–wheat–mung bean system resulted in 6% increase in SOC and 85% increase in soil microbial biomass carbon as compared with the conventional rice–wheat system. Application of crop residues, farm yard manure (5 t ha−1) and biofertilisers had greater amount of carbon fractions and carbon management index (CMI) over control and the recommended inorganic (NPKSZnB) treatment in the soil surface, particularly in the system where pulses are included. Interestingly, in the puddled rice system, passive carbon pool is more in surface soil than deeper layers. The relative proportion of active carbon pool in surface layer (0–20 cm) to subsurface layer (20–40 cm) was highest in rice–wheat–rice–chickpea (1.14:1) followed by rice–wheat–mung bean (1.07:1) and lowest in the rice–wheat system (0.69:1). Replacing wheat with chickpea either completely or during alternate year in the conventional rice–wheat system also had positive impact on SOC restoration and CMI. Therefore, inclusion of pulses in the rice-based cropping system and organic nutrient management practices had significant impact on maintaining SOC in an Inceptisol of the Indo-Gangetic plains of India.
Multiferroics, the study of materials which possess ferromagnetic and ferroelectric ordering in a single phase, has become an area of prominent research. Moreover, this behavior has been extensively studied in materials which possess a perovskite crystal structure such as BiFeO3 and YMnO3. Due to their weak saturation magnetic moment, many rare-earth orthoferrites are currently of extreme interest. Utilizing a solid-state reaction between Y2O3 and Fe2O3 we have developed the rare-earth orthoferrite YFeO3 and conducted a bulk material study to determine this material’s availability for thin film multiferroic research. The absence of Y2O3 and Fe2O3 impurities was confirmed using Copper-Kα XRD. Examination of the dependence of the magnetization M on the temperature T was conducted to determine the reliability of multiferroic behavior across varying temperatures in conjunction with the investigation of the dependence of M on the electric field strength H. Results clearly display ferromagnetic behavior in our bulk material, providing ample evidence that our bulk material is an excellent candidate for thin film studies. Future studies on multiferroic YFeO3 thin films grown via pulsed laser deposition on Lanthanum Aluminate substrates will be conducted. Detailed data will be provided via XRD and SQUID to confirm magnetic properties while impurities are non-existent in our thin films.
Over a 2-year period, 25 families comprising of 181 individuals of all ages were longitudinally observed for the excretion of Campylobacter species. Faecal samples were taken from all persons with diarrhoea. Specimens were also taken from apparently healthy individuals and from domestic animals living within the confines of the study families at monthly intervals.
The overall diarrhoea attack rate was 19 episodes per 100 person-years with peak incidence in the 1- to 4-year-old age group (76/100 person-years). Eight (11·5%) of the total episodes were campylobacter-associated and the overall rate of campylobacter positive diarrhoeal episodes were 2·2 per 100 person-years. Of the 1002 stool samples from healthy individuals 32 (3·2/100 samples) were positive for campylobacter. The organism was most frequently isolated from children under 1 year of age both during diarrhoeal episodes (11·5 per 100 person-years) and non-diarrhoeal (11·1 per 100 samples). Multiple infections in a family were rare. In 19·4% of the occasions one or more animals were campylobacter positive. However, only in 7·7% of these occasions was a human infection recorded within 1 month after the animal was found to be positive.
The study showed that the epidemiology of campylobacteriosis in this community was distinct compared to that observed in developed countries.
Lysozyme, an anti-bacterial enzyme, is mostly found in the body fluids, various tissues and secretions of animals and humans, and confers immunity against a wide range of bacterial species. The present study was carried out to elucidate the gene sequence of this enzyme in Indian Sahiwal × Holstein Friesian crossbred cattle and to explore the polymorphism of the gene as well as their association with milk production and somatic cell traits. The total length of lysozyme cDNA was found to be of 447 bp. The similarity with Bos taurus, human, pig, monkey, gorilla, mice, rat, chicken, dog and sheep was estimated as 99.1%, 85%, 81.0%, 85.2%, 84.3%, 77.9%, 77.9%, 41.4%, 40.5% and 24.6%, respectively. Polymorphism study of two fragments, extended exon1 including promoter, exon1 and partial intron1 (268 bp), and extended exon2 including partial intron1 and 2, and exon2 region (287 bp) of milk lysozyme gene was carried out by employing single-stranded conformation polymorphism (SSCP). In the extended exon1 fragment, three alleles namely A, B and C with frequencies of 0.59, 0.28 and 0.12 were observed while in the exon extended fragment, three different alleles – P, Q and R with respective frequencies of 0.61, 0.38 and 0.01 – were determined in Indian Sahiwal × Holstein Friesian cross. A total of eight haplotypes were found in this population where the most predominant one was h1 (0.52). Genotypes of exon1 extended fragment showed significant association with total milk yield, daily milk yield, peak yield and somatic cell score at P < 0.05 while that of exon2 extended fragment had significant correlation with only total lactational milk yield. Haplotype combinations also revealed significant association with total milk production where h1h1 homozygous showed highest yield during first lactation.
Nonlinear behaviour of azimuthally symmetric compressional hydromagnetic waves propagating along a cylindrical cold magnetized plasma-filled waveguide is investigated. A nonlinear Schrödinger equation describing the nonlinear evolution of such waves is derived. Numerical evaluation of the dispersive and nonlinear terms reveals that such waves are modulationally stable in the fundamental radial mode of propagation. Calculations are presented for the amplitude dependent frequency and wavenumber shifts.
Starting from a set of equations that lead to a linear dispersion relation coupling kinetic Alfvén waves and ion-acoustic waves, three-dimensional KdV equations are derived for these waves. These equations are then used to investigate the three-dimensional stability of solitary kinetic Alfvén waves and ion-acoustic waves by the small-k perturbation expansion method of Rowlands and Infeld. For kinetic Alfvén waves it is found that there is instability if the direction of the plane-wave perturbation lies inside a cone, and the growth rate of the instability attains a maximum when the direction of the perturbation lies in the plane containing the external magnetic field and the direction of propagation of the solitary wave.
Using reductive perturbation theory and a planar waveguide geometry, the effects of higher-order nonlinearity and finite boundaries on the propagation of electron plasma and ion-acoustic KdV solitons are investigated by taking into account finite electron and ion temperatures. For an electron plasma wave, the higher-order nonlinearity is found to increase the amplitude of the soliton and slightly decrease the width of the soliton compared with that predicted by the first-order theory. For an ion-acoustic wave the higher-order-nonlinearity and finite-boundary effects give rise to a W-shaped soliton.
The method of multiple scales is used to derive a nonlinear Schrödinger equation, which describes the nonlinear evolution of electron plasma ‘slow waves’ propagating along a hot cylindrical plasma column, surrounded by a dielectric medium and immersed in an essentially infinite axial magnetic field. The temperature is included as well as mobile ion effects for ail possible modes of propagation along the magnetic field. From this equation the condition for modulational instability for a uniform plasma wave train is determined.
Nonlinear interactions of two azimuthally symmetric compressional hydromagnetic waves propagating in a cylindrical waveguide filled with cold magnetized plasma are investigated. Two cases are considered: the nonlinear interaction of two identical oppositely propagating compressional waves and the nonlinear interaction of two compressional waves propagating with equal group velocities. In the first case the second-order perturbation fields generated through self- and mutual interactions of the waves are calculated and their effect on the otherwise-formed simple linear standing-wave pattern is studied. The possibility of observing a resonant nonlinear interaction is shown. In the second case, in order to describe the nonlinear evolution of the wave amplitudes, two coupled nonlinear Schrödinger (NLS) equations are presented. When excited individually, both the waves are seen to be modulationally stable; but when excited simultaneously, a strong nonlinear wave-wave coupling comes into play, which makes the waves modulationally unstable. The corresponding growth rate of the instability is also calculated.