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Hyperkalemia (HK) is common and potentially a life-threatening condition. If untreated, HK can progress to ventricular arrhythmia and cardiac arrest. Early treatment reduces mortality in HK. This study evaluates a novel protocol for identification and empiric management of presumed HK in the prehospital setting.
Methods:
This was a retrospective, observational chart review of a single, large, suburban Emergency Medical Services (EMS) system. Patients treated for presumed HK, with both a clinical concern for HK and electrocardiogram (ECG) changes consistent with HK, from February 2018 through February 2021 were eligible for inclusion. Patients were excluded if found to be in cardiac arrest on EMS arrival. Empiric treatment of HK included administration of calcium, sodium bicarbonate, and albuterol. Post-treatment, patients were placed on cardiac monitoring and adverse events recorded enroute to receiving hospital. Protocol compliance was assessed by two independent reviewers. Serum potassium (K) level was obtained from hospital medical records.
Results:
A total of 582 patients were treated for HK, of which 533 patients were excluded due to cardiac arrest prior to EMS arrival. The remaining 48 patients included in the analysis had a mean age of 56 (SD = 20) years and were 60.4% (n = 29) male with 77.1% (n = 37) Caucasian, 10.4% (n = 5) African American, and 12.5% (n = 6) Hispanic. Initial blood draw at the receiving facilities showed K >5.0mEq/L in 22 (45.8%), K of 3.5-5.0mEq/L in 23 (47.9%), and K <3.5mEq/L in three patients (6.3%). Independent review of the EMS ECG found the presence of hyperkalemic-related change in 43 (89.6%) cases, and five (10.4%) patients did not meet criteria for treatment due to lack of either appropriate ECG findings or clinical suspicion. No episodes of unstable tachyarrhythmia or cardiac arrest occurred during EMS treatment or transport.
Conclusion:
The study evaluated a novel protocol for detecting and managing HK in the prehospital setting. It is feasible for EMS crews to administer this protocol, although a larger study is needed to make the results generalizable.
Studies up to great extent have focused on investigating the possible consequences of supervisor incivility in organizations; however, surprisingly very little research has concentrated on its antecedents. Drawing on affective event theory, the aim of this study is to identify how role overload may cause the supervisor behavior uncivil toward their subordinates in the project environment by examining the mediating role of emotional exhaustion and moderating effect of time consciousness. Data were collected from both supervisors and their immediate subordinates from project-based organizations of Pakistan. After data consolidation, the final sample was 296 supervisor–subordinate dyads. The results revealed that supervisor role overload and emotional exhaustion is positively related with supervisor incivility and emotional exhaustion mediates this relationship. Time consciousness moderates the link between supervisor role overload and emotional exhaustion. The practical and theoretical implications of our findings are provided.
A compact co-planar waveguide (CPW) fed planar elliptical antenna has been designed and presented for super wideband (SWB) characteristics. The designed antenna has an overall size of 30 × 30 × 1.57 mm3, and it consists of an elliptical patch radiator fed using a modified 50 Ω CPW-fed tapered microstrip feed line. By using a semi-ring shaped structure with a tapered feed line, an impedance bandwidth of 180.66% has been observed from 1.27 to 25 GHz with a ratio bandwidth of 19.68:1. To validate simulation results, the designed antenna has been fabricated and measured, and a reasonable agreement has been observed between simulated and measured results. It has also been observed that the designed antenna offers good radiation properties over the entire operating bandwidth. The simulated average gain and radiation efficiency of the proposed SWB antenna is noted to be 4.3 dBi and 95.77%, respectively; while the measured average gain and radiation efficiency is 3.8 dBi and 94.69%, respectively.
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.
This study reported the justification and selection of acceptable γ criteria with respect to low (6 MV) and high (15 MV) photon beams for intensity-modulated radiation therapy quality assurance (IMRT QA) using the Gafchromic external beam therapy 3 (EBT3) film.
Materials and methods
Five-field step-and-shoot IMRT was used to treat 16 brain IMRT patients using the dual-energy DHX-S linear accelerator (Varian Medical System, Palo Alto, CA, USA). Dose comparisons between computed values of the treatment planning system (TPS) and Gafchromic EBT3 film were evaluated based on γ analysis using the Film QA Pro software. The dose distribution was analysed with gamma area histograms (GAHs) generated using different γ criteria (3%/2 mm, 3%/3 mm and 5%/3 mm) for the 6 and 15 MV photon beams, to optimise the best distance-to-agreement (DTA) criteria with respect to the beam energy.
Results
From the comparison between the dose distributions acquired from the TPS and EBT3 film, a DTA criterion of 3%/2 mm showed less dose differences (DDs) with passing rates up to 93% for the 6 MV photon beams, while for the 15 MV a relaxed DTA criterion of 5%/3 mm was consistent with the DD acceptability criteria with a 95% passing rate.
Conclusions
Our results suggested that high-energy photon beams required relaxed DTA criteria for the brain IMRT QA, while low-energy photon beams showed better results even with tight DTA criteria.
This work reports our study to commission a radiochromic film dosimetry system using the timely EBT3 film. We carried out dosimetric evaluations on different characteristics of photon beams (e.g., flatness, symmetry and penumbra) in radiation dose delivery.
Materials and Methods
A Varian linear accelerator producing 6 and 15 MV photon beams with 120 multi-leaf collimator was used in this study. PTW ionisation chamber was used to measure the beam characteristics such as symmetry, flatness and penumbra and these measurements were used to commission the radiochormic EBT3 film dosimetry system. The results of irradiated films were analysed using the radiochromic film QA Pro software 2016.
Results
The measured film doses were analysed at two different colour channels (green and red) using two scanning geometries (i.e., upper or lower side of film facing the scanner light source) at two dose levels (10 and 40 Gy). The difference between the ionisation chamber and film results was found insignificant and within the acceptable range as per the World Health Organisation standard.
Conclusion
Results of the comparison between the ionisation chamber and film measurements show that our radiochormic EBT3 film dosimetry system is reliable and cost-effective in the output measurement of a linear accelerator. Our measurements confirm that our EBT3 film dosimetry agreed well with the ionisation chamber, and can be used as a re-validation tool for linear accelerator quality control.
Oligodeoxynucleotides (ODNs) containing cytosine-phosphate-guanosine sequence (CpG) is considered as an immune stimulator when it is fed to animals. These synthetic molecules mount different immune responses in the animals including mice, chickens, ducks, dogs and horses. CpG ODNs induce specific antigenic immunity against co-administered vaccines and are well tolerated in healthy individuals and are capable of stimulating toll-like receptors (TLRs) such as TLR-9 to activate innate immunity. The CpG ODNs can be used as an adjuvant in different vaccines synthesised specifically for poultry diseases caused by viruses and bacteria. In chickens, CpG ODNs stimulate TLRs involved in humoral immunity. CpG ODNs have been used as mucosal vaccine adjuvants against several pathogens, including avian influenza and Newcastle disease. The CpG ODNs function to protect the chickens from Newcastle disease by producing plasma dendric cells (pDCs) which ultimately produce interferons (INFs). The inoculation of CpG ODNs along with the cationic microparticles and DNA vaccine for infectious bursal disease virus result in the influx of T cells and a reduction of antigen load. When CpG ODNs are used against avian leucosis, they result in significantly higher antibody titres. In many other vaccines e.g., infectious laryngotracheitis, infectious bronchitis, herpes, viral enteritis, Marek's disease virus, E. coli and Salmonella spp. including CpG ODNs exhibit immunostimulatory effects. In conclusion, CpG ODNs may be used as effective adjuvants in viral, bacterial and parasitic vaccines in poultry.
Traditional diagnostic capabilities (serology and culture) are not enough to monitor the poultry infections efficiently. For effective control of poultry infections, a regular program incorporating simple and cost-effective molecular diagnostics is necessary. On this rationale, it is possible to present working molecular diagnostic technology that would work equally well in field as well as in the laboratory. Recently, the loop-mediated isothermal amplification (LAMP) assay has emerged as simple and inexpensive diagnostic tool for the molecular detection of various animal pathogens. To perform LAMP, no specialised instruments (e.g. thermal cycler) are required, permitting its use in developing countries. Various reliable LAMP assays have been reported for the detection of different poultry pathogens. However, still there is a need to improve the sensitivity, specificity, reproducibility, user-friendliness, delivery to end-user and affordability of LAMP assays. This article reviews current LAMP assays available for the molecular detection of important viral, bacterial and protozoan pathogens of poultry. It focuses on the various aspects of LAMP for the diagnosis of important poultry pathogens based upon pathogen type, specimen, target genes, LAMP primer types, detection limits, fluorescent detectors and LAMP chemistry used. This paper provides updates on principle, instrumentation, basic methodology, quantification capability, reagents and kits used currently in performing LAMP.
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.
Spatial confinement effects on plasma parameters and surface morphology of laser-ablated Mg are studied by introducing a metallic blocker as well as argon (Ar) gas at different pressures. Nd: YAG laser at various fluences ranging from 7 to 28 J/cm2 was employed to generate Mg plasma. Confinement effects offered by metallic blocker are investigated by placing the blocker at different distances of 6, 8, and 10 mm from the target surface; whereas spatial confinement offered by environmental gas is explored under four different pressures of 5, 10, 20, and 50 Torr. Laser-induced breakdown spectroscopy analysis revealed that both plasma parameters, that is, excitation temperature and electron number density initially are strongly dependent upon both pressures of environmental gases and distances of blockers. The maximum electron temperature of Mg plasma is achieved at Ar gas pressure of 20 Torr, whereas maximum electron number density is achieved at 50 Torr. It is also observed that spatial confinement offered by metallic blocker is responsible for the significant enhancement of both electron temperature and electron number density of Mg plasma. Maximum values of electron temperature and electron number density without blocker are 8335 K and 2.4 × 1016 cm−3, respectively, whereas these values are enhanced to 12,200 K and 4 × 1016 cm−3 in the presence of blocker. Physical mechanisms responsible for the enhancement of Mg plasma parameters are plasma compression, confinement and pronounced collisional excitations due to reflection of shock waves. Scanning electron microscope analysis was performed to explore the surface morphology of laser-ablated Mg. It reveals the formation of ripples and channels that become more distinct in the presence of blocker due to plasma confinement. The optimum combination of blocker distance, fluence and Ar pressure can identify the suitable conditions for defining the role of plasma parameters for surface structuring.
Magneto polymer matrix composites (MPMC) is a new class of magnetic polymer materials which are being developed and under investigation as potential materials for tomorrow’s aircraft structures. It encompasses magnetic, particulate strengthening (dispersion strengthening) as well as fiber reinforcement/strengthening characteristics which are sought out to be utilized toward making efficient future aerospace composite materials. Various types of ferrites including barium, cobalt, iron, and strontium were explored for being used in making new composites. Here a comprehensive review of the synthesis, structure, properties, thermodynamics, surface chemistry, and phase transformations of individual ferrites and clusters of ferrites as fillers is presented. In particular a discussion about the rational control of the mechanical, physical, thermal, electrical, and magnetic properties of magneto polymer matrix composites through surface functionalization, modification, emulsification/compounding/blending, heat treatment (phase transformation and separation), and control of processing conditions (temperature, pressure and geometry of mold) is provided. These smart materials have a wide range of potential applications in medicine, drug delivery, bio imaging, bio marking, tissue engineering, electromagnetic interference (EMI) and electromagnetic force (EMF) shielding, and as competent materials for aerospace structural applications.
Bulk metallic glass and their composites are unique new materials which have superior mechanical and structural properties as compared to existing conventional materials. Owing to this, they are potential candidates for tomorrow’s structural applications. However, they suffer from disadvantages of poor ductility and little or no toughness which render them brittle and they manifest catastrophic failure on the application of force. Their behavior is dubious and requires extensive experimentation to draw conclusive results. In present study, an effort has been made to overcome this pitfall by simulation. A quantitative mathematical model based on KGT theory has been developed to describe nucleation and growth of second phase dendrites from melt in glassy matrix during solidification. It yields information about numerical parameters necessary to understand the behaviour of each individual element in multicomponent sluggish slurry and their effect on final microstructural evolution. Model is programmed and simulated in MATLAB®. Its validation is done by comparison with identical curves reported in literature previously for similar alloys. Results indicate that the effect of incorporating all heat transfer coefficients at macroscopic level and diffusion coefficients at microscopic level play a vital role in refining the model and bringing it closer to actual experimental observations. Two types of hypo and eutectic systems namely Zr65Cu15Al10Ni10 and Zr47.5Cu45.5Al5Co2 respectively were studied. Simulation results were found to be in good agreement with prior simulated and experimental values.
The effects of axial magnetic field on the properties of the ions ejected from Nd:YAG laser (wavelength = 1064 nm, pulse duration = 6 ns) produced expanding Cu plasma were investigated. A plane Cu target, without and with 0.23 T axial magnetic field at its surface, was irradiated in the fluence range of 2–24 J/cm2. The ions emitted along the target surface normal were analyzed with the help of ion collector and time-of-flight electrostatic ion energy analyzer. The integrated ion yield, highest ion charge state, average ion energy, and energy of individual ion charge states were found to increase by application of the magnetic field. The initial parameters of the non-equilibrium plasma such as average ion charge, equivalent potential, electron temperature, electron density, Debye length, and transient electric field were estimated from the experimental results obtained without and with application of the magnetic field. The increase of ion yield and ion charge state by application of magnetic field are most probably due to the trapping of electrons in front of the target surface, which boosts up the electron impact ionization process. The ion energy increment due to the magnetic field is discussed in the frame work of electrostatic model for ion acceleration in laser plasma.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases affecting wheat. In this study, seven gene-linked markers were used to identify the presence of stripe rust resistant genes in 51 accessions of synthetic hexaploid of wheat which were found to be resistant at seedling plant stage. Molecular marker-based gene identification showed the presence of Yr5, Yr10 and Yr15 in three accessions, Yr36 in three accessions, Yr48 in seven accessions, YrR61 in four accessions, and YrTP1 in ten accessions of resistant hexaploid of wheat. These gene-linked markers were also used for the detection of genetic diversity. A total of 68 alleles were detected by these seven gene-linked markers. The mean number of allele was 11.3 alleles per locus. Genetic diversity values ranged from 0.34 to 0.93, with highest genetic diversity value of 0.93 detected for marker Xwm477. The lowest genetic diversity value was observed for marker Xbarc167. The polymorphic information content value ranged from 0.33 to 0.92 with an average of 0.54. The highest number of alleles (n= 24) were detected for marker Xwmc477. The evidence in this study on the basis of genetic diversity and presence of Yr genes in synthetic hexaploid wheat accessions will be useful in further breeding programmes.
In this work, plasma is produced by irradiating a Ti target with 10 ns pulsed Nd:YAG (λ = 1064 nm) laser. The laser fluence at the target was varied in the range of 2–20.3 J/cm2. The ion signal from freely expanding Ti plasma in vacuum was characterized with the help of ion collector and time-of-flight electrostatic energy analyzer. The ion charge state was found to increase with the laser fluence and maximum available ion charge in this fluence range is Ti4+. A correlation between the intensities of various ion charge states was observed, which indicates that higher charge states are most probably produced through stepwise ionization mechanism. It is also observed that charge state distribution of plasma can be controlled by variation of the laser fluence. In addition, energy distribution of ion charge states Tin+ (n = 1–4) is measured by varying back plate voltage of the electrostatic energy analyzer for a fixed laser fluence of 20.3 J/cm2. Ions energy distributions were in the range of 0.36–3.0 keV and the most probable ion energy was found to increase linearly with ion charge state. The estimated equivalent potential at the laser fluence of 20.3 J/cm2 is about 310 V. These results are in good agreement with the predictions of electrostatic model of ion acceleration in laser plasma.
Newcastle Disease (ND) is regarded as one of the major diseases of poultry because of the devastating losses that the virulent form of the ND virus can impose on both commercial and domestic chickens. However, the disease can be controlled through the administration of effective vaccines. Almost all the commercially available ND vaccines require refrigeration and begin to deteriorate rapidly after 1-2 hours if left at room temperature (around 25°C). Subsequently, because maintaining an adequate supply of refrigerated facilities may be a difficult task in many countries with unreliable electrical supplies, the development and large scale production of an effective thermostable ND vaccine seems imperative to support the poultry industry. Such vaccines should be resilient to damage associated with either very cold or hot environments so there are no concerns about the viability of the vaccine in response to temperatures fluctuations that can occur in extreme environments when the difference in temperature during cold and warm seasons can vary greatly. In the following review paper, the development of such a vaccine is discussed, including molecular characterisation, organ tropism of vaccine strains, production, as well as administration methods and their efficacy. It addition, the potential payback has been calculated alongside opportunities provided by removing vaccines from cold chain storage.