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It is shown that an electron, positron and ion plasma can be self-organized to a double Beltrami state – the superposition of two force-free states. The scale parameters which determine the nature of the self-organized structures are found to depend on the number densities of the plasma species. The loss of equilibrium in slowly evolving double Beltrmi states is investigated. The effects of density ratios, helicities, positron flows and energy on equilibrium are investigated. It is found that the double Beltrami state transforms to a single Beltrami state at the termination of equilibrium. It is also shown that much of the magnetic energy converts to the flow kinetic energy through catastrophic transformation.
Two-photon absorption (TPA) of Au-ion irradiated glasses in the femtosecond regime has been analyzed by an open-aperture Z scan technique. Three types of glasses, namely GIL49, BK7, and Glass B were irradiated by using 1700 keV Au+ ion beams. Samples were post-annealed at 600°C for 5 h. Penetration depth and distribution of Au+ ions having 1700 keV energy within glass substrates were estimated by transport of ions in matter (TRIM) simulations. Detailed calculations with full-damage cascades were performed for each sample, taking into account the chemical composition of glass substrates. TRIM results reveal that there is no significant change in ion range, straggling, and ion distribution with the change in the substrate composition. However, Z scan results showed a difference in TPA coefficients for all three glasses. Extent of crosslinking within each of irradiated sample, owing to its chemical composition, may have affected their TPA coefficients.
Radiotherapy is an option to treat high-grade laryngeal dysplasia. This study aimed to evaluate the use of intensity-modulated radiotherapy, 55 Gy in 20 daily fractions, in treating this disease.
Acute toxicity was evaluated in all 14 patients treated. In 10 patients, functional voice outcome was measured using the Voice Handicap Index, and the Grade, Roughness, Breath, Asthenia, Strain (‘GRBAS’) scale. These measurements were performed pre-treatment and three months after intensity-modulated radiotherapy.
All but one patient managed to complete radiotherapy. Acute toxicity was significant (one patient developed grade 4 and three patients developed grade 3 dysphagia). Four patients required hospital admission. In 9 out of 10 patients, radiotherapy improved voice quality.
This radiotherapy regimen using intensity-modulated radiotherapy for laryngeal dysplasia is feasible and provided excellent functional outcome, but acute toxicity was significant. Dose de-escalation can be considered in the framework of clinical trials.
To verify dose delivery and quality assurance of volumetric-modulated arc therapy (VMAT) for head and neck (H&N) cancer.
The Imaging and Radiation Oncology Core Houston (IROC-H) H&N phantom with thermoluminescent dosimeters (TLDs) and films, were imaged with computed tomography scan and the reconstructed image was transferred to pinnacle treatment planning system (TPS). On TPS, the planning target volume (PTV), secondary target volume (STV) and organ at risk (OAR) were delineated manually and a treatment plan was made. The dose constraints were determined for the concerned organs according to IROC-H prescription. The treatment plan was optimised using adoptive convolution algorithm to improve dose homogeneity and conformity. The dose calculation was performed using C.C Convolution algorithm and a Varian True Beam linear accelerator was used to deliver the treatment plan to the H&N phantom. The delivered radiation dose to the phantom was measured through TLDs and GafChromic external beam radiotherapy 2 (EBT2) films. The dosimetric performance of the VMAT delivery was studied by analysing percent dose difference, isodose line profile and gamma analysis of the TPS-computed dose and linac-delivered doses.
The percent dose difference of 3.8% was observed between the planned and measured doses of TLDs and a 1.5-mm distance to agreement (DTA) was observed by comparing isodose line profiles. Passed the gamma criteria of 3%/3 mm was with good percentages.
The dosimetric performance of VMAT delivery for a challenging H&N radiotherapy can be verified using TLDs and films embedded in an anthropomorphic H&N phantom.
This paper discusses how the processes of Continuing Airworthiness Management Organisations can be made more efficient by applying Lean principles and digital solutions, to obtain costs savings and improved compliance standards. Lean management is the process of eliminating waste by maximising value through balancing workloads and cutting out inefficient processes. Though Lean was initially applied to manufacturing production lines, an opportunity exists to apply the principles of Lean in airworthiness management. One such aspect of airworthiness management is the processing of records which is an essential part of safety and compliance. Software solutions designed with Lean philosophy and focus on airworthiness management processes can provide benefits in managing the flow of records and extracting actionable information from them for cost reduction and improving safety. Further value can be extracted by applying additional software solutions that will lay a strong foundation for machine learning and predictive analytics – taking aircraft maintenance from a reactive model towards a proactive model.
The mainstay of management of epistaxis refractory to first aid and cautery is intranasal packing. This review aimed to identify evidence surrounding nasal pack use.
A systematic review of the literature was performed using standardised methodology.
Twenty-seven eligible articles were identified relating to non-dissolvable packs and nine to dissolvable packs. Nasal packing appears to be more effective when applied by trained professionals. For non-dissolvable packs, the re-bleed rates for Rapid Rhino and Merocel were similar, but were higher with bismuth iodoform paraffin paste packing. Rapid Rhino packs were the most tolerated non-dissolvable packs. Evidence indicates that 96 per cent of re-bleeding occurs within the first 4 hours after nasal pack removal. Limited evidence suggests that dissolvable packs are effective and well tolerated by patients. There was a lack of evidence relating to: the duration of pack use, the economic effects of pack choice and the appropriate care setting for non-dissolvable packs.
Rapid Rhino packs are the best tolerated, with efficacy equivalent to nasal tampons. FloSeal is easy to use, causes less discomfort and may be superior to Merocel in anterior epistaxis cases. There is no strong evidence to support prophylactic antibiotic use.
Avian influenza virus (AIV) type A subtype H9N2 usually causes mild asymptomatic infections, and is mostly undetected and is, therefore, under-reported. This has allowed the virus to rapidly evolve via mutations and reassortments in its genome with other avian influenza subtypes especially H1N1, H5N1 and H7N3 thereby introducing new variant strains and producing severe disease. It has been reported that the AIV H9N2 donated its internal genes for the devastating 1997 Hong Kong outbreak and furthermore, it may be the cause of the next influenza pandemic. There are many factors such as its wide host range, ability to cross the species barrier, ecological diversity, antiviral resistance and zoonotic importance that make it an excellent candidate for the next influenza pandemic. These and other factors like ineffective vaccination, negative immunological pressures, lack of surveillance, which contribute to its continuous persistence and evolutionary dynamics are discussed in this paper. It is important to take the necessary measures to control and prevent its unchecked circulation to prevent the future outbreaks.
In present work, we investigate numerical simulation of steady natural convection flow in the presence of weak magnetic Prandtl number and strong magnetic field by involving algebraic decay in mainstream velocity. Before passing to the numerical simulation, we formulate the set of boundary layer equations with the inclusion of the effects of algebraic decay velocity, aligned magnetic field and buoyant body force in the momentum equation. Later, finite difference method with primitive variable formulation is employed in the physical domain to compute the numerical solutions of the flow field. Graphical results for the velocity, temperature and transverse component of magnetic field as well as surface friction, rate of heat transfer and current density are presented and discussed. It is pertinent to mention that the simulation is performed for different values of algebraic decay parameter α, Prandtl number Pr, magnetic Prandtl number Pm and magnetic force parameter S.
Cholera is an important public health problem in Bangladesh. Interventions to prevent cholera depend on their cost-effectiveness which in turn depends on cholera incidence. Hospital-based diarrhoeal disease surveillance has been ongoing in six Bangladeshi hospitals where a systematic proportion of patients admitted with diarrhoea were enrolled and tested for Vibrio cholerae. However, incidence calculation using only hospital data underestimates the real disease burden because many ill persons seek treatment elsewhere. We conducted a healthcare utilization survey in the catchment areas of surveillance hospitals to estimate the proportion of severe diarrhoeal cases that were admitted to surveillance hospitals and estimated the population-based incidence of severe diarrhoea due to V. cholerae by combining both hospital surveillance and catchment area survey data. The estimated incidence of severe diarrhoea due to cholera ranged from 0·3 to 4·9/1000 population in the catchment area of surveillance hospitals. In children aged <5 years, incidence ranged from 1·0 to 11·0/1000 children. Diarrhoeal deaths were most common in the Chhatak Hospital's catchment area (18·5/100 000 population). This study provides a credible estimate of the incidence of severe diarrhoea due to cholera in Bangladesh, which can be used to assess the cost-effectiveness of cholera prevention activities.
It is shown that there exists a strong interaction between the magnetic and kinetic aspects of a multi-ion plasma. The interaction appears as a system of simultaneous equations which show the alignment of vortices to flows and satisfy the Beltrami condition. Solving these equations lead to a non-force-free magnetic field which can be cast as a superposition of three multiscale force-free magnetic field configurations. It is the consequence of different Beltrami parameters of positive and negative ion fluids. It is also shown that self-organized paramagnetic and diamagnetic field structures could be created by varying the vorticities and flows of ion fluids.
1.1 In recent years insurance companies have begun to employ marketing techniques in search of greater success in an increasingly competitive market place. Several companies have Marketing Departments. However, those who have used marketing techniques most efficiently are not necessarily those with the largest departments.
1.2 Too often marketing is confused with promotion which is but one facet of a multi-faceted discipline. Another common mistake is to regard marketing as a subset of selling. This is understandable because most senior marketing appointments in the insurance industry have gone to people with a sales background. Levitt in his classic article Marketing Myopia in Harvard Business Review said:
“Selling focuses on the needs of the seller; marketing on the needs of the buyer. Selling is preoccupied with the seller's need to convert his product into cash; marketing with the idea of satisfying the needs of the customer by means of the product and the whole cluster of things associated with creating, delivering and finally consuming it.
The selling concept starts with the company's existing products and calls for heavy promotion and selling to achieve profitable sales. The marketing concept is a customers' needs and wants orientation backed by integrated marketing effort aimed at generating customer satisfaction as a key to satisfying customer goals.
The determination of what is to be produced should not be in the hands of the companies but in the hands of the customers. The companies produce what the consumers want and in this way maximize consumer welfare and earn their profits.”
Imprinting is a well-established technique to induce recognition features in both organic and inorganic materials for a variety of target analytes. In this study, ion imprinted polysiloxanes with varying percentage of coupling agent i.e. 3-chloro propyl trimethoxy silane (CPTM) were synthesized by sol-gel method for imprinting of Cr3+. The imprinting of Cr3+ in cross-linked siloxane network was investigated by FT-IR which indicates the metal ion is coordinated with oxygen atoms of polysiloxanes. SEM images revealed that imprinted polysiloxanes possess uniform particles of submicron size. It was experienced that by increasing the concentration of CPTM up to 10% (v/v) substantially improves the binding capacity of polysiloxanes which allows us to recognized Cr3+ down to 50µg/L. Furthermore, the selectivity of Cr3+-imprinted polysiloxanes was evaluated by treating them with other competing metal ions of same concentration i.e. Cr6+, Pb2+ and Ni2+. In this regard, polysiloxanes showed much higher binding for imprint ion i.e. Cr3+ in comparison to above mentioned metal ions. Finally, the regenerated polysiloxanes were studied in order to reuse them thus, developing cost effective biomimetic sensor coatings.
Pheasants and peafowl have been used as ornamental birds worldwide because of their beauty and use as game birds. They can be hampered by the disease mycoplasmosis in breeding pens, wildlife parks and zoos. This review paper describes the prevalence, diagnostic procedures and different combinations of treatments for mycoplasmosis in these birds. This paper also discusses the association of prevalence with management practices.
The relaxation of an electron-depleted electronegative dusty plasma with two-negative ions is investigated. When the ratio of canonical vorticities to corresponding flows of all the plasma species is the same and all inertial and non-inertial forces are present, the relaxed state appears as a double Beltrami magnetic field which is the superposition of two force-free relaxed states. The numerical results show that highly diamagnetic relaxed magnetic fields can be obtained by controlling the flow and vorticities through a single Beltrami parameter. The study is useful to investigate the creation of diamagnetic plasma configurations which are considered to be very important in the context of nuclear fusion.
A relativistically hot electron, positron and ion (e–p–i) plasma relaxes to a triple curl Beltrami (TCB) field. The TCB field being the superposition of three Beltrami fields is characterized by three scale parameters and hence there exist multiscale structures in the system. It is shown that temperatures of the plasma constituents strongly affect the scale parameters. Generally, the scale parameters associated with the TCB field may be a combination of real and complex roots. The numerical results show that for given Beltrami parameters, an increase in the thermal energy of plasma particles could transform the real eigenvalues to complex ones. It is also observed that one component is more strongly affected relative to other components on increasing temperatures of plasma species. Two different vortices become the same at higher thermal energies. This suggests that it is possible to create high β (kinetic to magnetic pressure ratio) and fully diamagnetic plasma configurations. The study has a potential relevance to space, astrophysics and laboratory plasmas.
The boundary layer flow of an Eyring-Powell fluid over a stretching surface subject to the convective boundary condition is investigated. Nonlinear problem is computed and a comparative study is presented with the existing results in viscous fluid. The constructed differential systems have been solved for homotopic solutions. Convergence of series solutions has been discussed. Special emphasis has been given to the effects of material parameters of fluid (ε), (δ), Biot number (γ) and Prandtl number (Pr) on the velocity and temperature profiles. Tabulated values of Nusselt number and skin friction for different emerging parameters are also illustrated. It is noted that the boundary layer thickness is an increasing function of (ε) and decreasing function of (δ). However the temperature and thermal boundary layer thickness decrease when the values of (ε) and (δ) are increased.
Carbon nanotube-spinel lithium titanate (CNT-Li4Ti5O12) nanoparticles have been synthesized by hydrothermal reaction and higher-temperature calcinations with LiOH·H2O and TiO2 precursors in the presence of carbon nanotubes sources. The CNT-Li4Ti5O12 nanoparticles have been characterized by X-ray diffraction (XRD), high angle annular dark field (HAADF) images, and selected area electron diffraction (SAED). The particles exhibited a spinel cubic crystal phase and homogenous size distribution, with sizes around 50-70 nm. HAADF imaging confirmed that carbon content exists on the surface of the CNT-Li4Ti5O12 nanoparticles with graphitic carbon coating of 3-5 nm thickness under 800oC in the Ar gas. The graphitic carbon phase was further confirmed with Raman spectroscopy analysis on powder samples. Electrochemical characteristics were evaluated with galvanostatic discharge/charge tests, which showed that the initial discharge capacity is 172 mA·h/g at 0.1C. The nanoscale carbon layers uniformly coated the particles, and the interconnected carbon nanotube network is responsible for the improved charge rate capability and conductivity.