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The effects of pantothenic acid (PA) and folic acid (FA) addition on digestibility coefficient, ruminal fermentation and urinary purine derivative (PD) excretion in dairy bulls were evaluated. Eight rumen-cannulated Holstein dairy bulls were allocated to a replicated 4 × 4 Latin square design according to a 2 × 2 factorial arrangement. Diets were supplemented with two levels of FA (0 or 8.0 mg/kg dietary dry matter [DM]) and two of PA (0 or 60 mg/kg DM). The PA × FA interaction was not significant for all variables. Both supplements increased DM intake and average daily gain, but decreased a feed conversion ratio. Digestibility of DM, organic matter, crude protein and neutral detergent fibre increased, but ether extract digestibility was unchanged for both supplements. Digestibility of acid detergent fibre only increased with FA supplementation. For both supplements, ruminal pH and ammonia nitrogen (N) decreased, but total volatile fatty acid (VFA) concentration increased. Acetate proportion only increased with FA supplementation. Propionate proportion decreased for both supplements. Consequently, the acetate to propionate ratio increased. For both supplements, activity of xylanase and pectinase, population of Ruminococcus albus, R. flavefaciens, Fibrobacter succinogenes and Ruminobacter amylophilus and total PD excretion increased. Additionally, activity of carboxymethylcellulase, cellobiase, α-amylase and protease, and population of total bacteria, fungi, protozoa, methanogens, Butyrivibrio fibrisolvens and Prevotella ruminicola increased with FA addition. The results suggested that PA and FA supplementation stimulated ruminal microbial growth and enzyme activity, resulting in an increased digestibility coefficient and ruminal total VFA concentration in dairy bulls.
The strong-coupling mode, called the “quasimode”, is excited by stimulated Brillouin scattering (SBS) in high-intensity laser–plasma interactions. Also SBS of the quasimode competes with SBS of the fast mode (or slow mode) in multi-ion species plasmas, thus leading to a low-frequency burst behavior of SBS reflectivity. Competition between the quasimode and the ion-acoustic wave (IAW) is an important saturation mechanism of SBS in high-intensity laser–plasma interactions. These results give a clear explanation of the low-frequency periodic burst behavior of SBS and should be considered as a saturation mechanism of SBS in high-intensity laser–plasma interactions.
Diagnosis, treatment, and prevention of vector-borne disease (VBD) in pets is one cornerstone of companion animal practices. Veterinarians are facing new challenges associated with the emergence, reemergence, and rising incidence of VBD, including heartworm disease, Lyme disease, anaplasmosis, and ehrlichiosis. Increases in the observed prevalence of these diseases have been attributed to a multitude of factors, including diagnostic tests with improved sensitivity, expanded annual testing practices, climatologic and ecological changes enhancing vector survival and expansion, emergence or recognition of novel pathogens, and increased movement of pets as travel companions. Veterinarians have the additional responsibility of providing information about zoonotic pathogen transmission from pets, especially to vulnerable human populations: the immunocompromised, children, and the elderly. Hindering efforts to protect pets and people is the dynamic and ever-changing nature of VBD prevalence and distribution. To address this deficit in understanding, the Companion Animal Parasite Council (CAPC) began efforts to annually forecast VBD prevalence in 2011. These forecasts provide veterinarians and pet owners with expected disease prevalence in advance of potential changes. This review summarizes the fidelity of VBD forecasts and illustrates the practical use of CAPC pathogen prevalence maps and forecast data in the practice of veterinary medicine and client education.
Structure and optical properties have been successfully determined for a series of niobium- and tantalum-containing layered alkaline-earth silicate compounds, Ba3(Nb6−xTax)Si4O26 (x = 0.6, 1.8, 3.0, 4.2, 5.4). The structure of this solid solution was found to be hexagonal P-62m (No. 189), with Z = 1. With x increases from 0.6 to 5.4, the lattice parameter a increases from 8.98804(8) to 9.00565(9) Å and c decreases from 7.83721(10) to 7.75212(12) Å. As a result, the volume decreases from 548.304(11) to 544.479(14) Å3. The (Nb/Ta)O6 distorted octahedra form continuous chains along the c-axis. These (Nb/Ta)O6 chains are in turn linked with the Si2O7 groups to form distorted pentagonal channels in which Ba ions were found. These Ba2+ ions have full occupancy and a 13-fold coordination environment with neighboring oxygen sites. Another salient feature of the structure is the linear Si–O–Si chains. When x in Ba3(Nb6−xTax)Si4O26 increases, the bond valence sum (BVS) values of the Ba sites increase slightly (2.09–2.20), indicating the size of the cage becoming progressively smaller (over-bonding). While SiO cages are also slightly smaller than ideal (BVS range from 4.16 to 4.19), the (Nb/Ta)O6 octahedral cages are slightly larger than ideal (BVS range from 4.87 to 4.90), giving rise to an under-bonding situation. The bandgaps of the solid solution members were measured between 3.39 and 3.59 eV, and the x = 3.0 member was modeled by density functional theory techniques to be 3.07 eV. The bandgaps of these materials indicate that they are potential candidates for ultraviolet photocatalyst.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
With the aims of overcoming the limitations of the existing basic flow model derived from an axisymmetric generating body and extending the aerodynamic design method of the airframe/inlet integrated waverider vehicle, this study develops an upgraded basic flow model derived from an axisymmetric shock wave. It then upgrades the design method for airframe/inlet integration of an air-breathing hypersonic waverider vehicle, which is termed the ‘full-waverider vehicle’ in this study. In this paper, first, the design principle and method for the upgraded full-waverider vehicle derived from an axisymmetric basic shock wave are described in detail. Second, an upgraded basic flow model that accounts for both internal and external flows is derived from an axisymmetric basic shock wave by use of both the streamline tracing method and the method of characteristics (MOC). Third, the upgraded full-waverider vehicle is developed from the upgraded basic flow model by the streamline tracing method. Fourth, the design theories and methodologies of both the upgraded basic flow model and the upgraded full-waverider vehicle are validated by a numerical computation method. Finally, the aerodynamic performances and viscous effects of both the upgraded basic flow model and the upgraded full-waverider vehicle are analysed by numerical computation. The obtained results show that the upgraded basic flow model and aerodynamic design method are effective for the design of the airframe/inlet integration of an air-breathing hypersonic waverider vehicle.
Global inequity in access to and availability of essential mental health services is well recognized. The mental health treatment gap is approximately 50% in all countries, with up to 90% of people in the lowest-income countries lacking access to required mental health services. Increased investment in global mental health (GMH) has increased innovation in mental health service delivery in LMICs. Situational analyses in areas where mental health services and systems are poorly developed and resourced are essential when planning for research and implementation, however, little guidance is available to inform methodological approaches to conducting these types of studies. This scoping review provides an analysis of methodological approaches to situational analysis in GMH, including an assessment of the extent to which situational analyses include equity in study designs. It is intended as a resource that identifies current gaps and areas for future development in GMH. Formative research, including situational analysis, is an essential first step in conducting robust implementation research, an essential area of study in GMH that will help to promote improved availability of, access to and reach of mental health services for people living with mental illness in low- and middle-income countries (LMICs). While strong leadership in this field exists, there remain significant opportunities for enhanced research representing different LMICs and regions.
Particle-in-cell (PIC) and Vlasov simulations both solve the Vlasov equation. The Vlasov equation (cf. Chapter 2) governs the evolution of the distribution function of charged particles (electrons, ions) in the six-dimensional phase space, consisting of three velocity (or momentum) dimensions and three position dimensions, plus time. It offers an accurate description of a plasma in the collisionless limit; that is, when the particles are affected by long-range electric and magnetic fields only, and when short-range fields from their nearest neighbors can be neglected.
PIC simulations resolve the distribution function statistically with macro-particles (or super-particles) and follows the solution over trajectories along which the distribution function is constant; the characteristics are given by the equations of motion for the charged particles. This is the Lagrangian description. Many PIC codes have been developed over the years; modern PIC codes include the plasma simulation code (PSC) originally developed by Hartmut Ruhl, the implicit iPIC3D code aimed at connecting kinetic and magnetohydrodynamic time scales, the EPOCH code, partially based on PSC, the VSIM/VORPAL code, the OSIRIS code, and QuickPIC. PIC simulations are very adaptive and efficient for many problems, such as high-energy beam–plasma and laser–plasma interactions. On the other hand, they also have limitations; the numerical noise and slow convergence with increasing number of particles are some issues. There is also the need to resolve the Debye length with particles to avoid artificial numerical heating.
A different strategy is followed in Vlasov simulations using a Eulerian description. Here, the distribution function is treated as a phase fluid resolved on a fixed numerical grid. Vlasov simulations do not have the statistical noise of PIC simulations; they can also more accurately resolve the high-velocity tail of the particle distribution functions. On the other hand, Vlasov simulations in higher dimensions are very memory demanding due to the need to resolve the six-dimensional phase space on a numerical grid. In some cases, the distribution function can also become oscillatory in phase space, leading to sharp gradients and a need to introduce numerical dissipation in velocity space whilst avoiding artificial numerical heating due to the broadening of the distribution in velocity space. Hence, the choice between PIC and Eulerian Vlasov simulations strongly depends on the physical problem at hand.
The laser, with its coherent, monochromatic, and well collimated character, has been a most remarkable discovery of the twentieth century. Along with semiconductors, its multifaceted applications have broadly touched and greatly improved our lives – it has made an indelible mark in the field of sensing, printing, barcode scanning, surgery, communications, and so on. It has also become a major tool for scientific research. For example, Thomson scattering and laser induced fluorescence are important tools for plasma diagnostics. Lasers have been used successfully for cooling of atoms and heating of plasmas.
The laser peak power has increased about a 1000 fold every decade since its invention. Starting from hundred watts in the 1960s, table top terawatt Ti: sapphire lasers became available in the 1990s following the discovery of the chirped pulse amplification (CPA) by Mourou and Strickland in 1985. These lasers do not only have high power but also very short pulses of a few femtoseconds, opening a new field of ultra-short pulse lasers and their interactions with matter, such as electron dynamics in molecules. In the past few years, we have seen worldwide efforts to build high power laser infrastructures. The Extreme Light Infrastructure (ELI) has been approved to construct three petawat laser facilities in Eastern Europe. Similar efforts are being made in Korea, Japan and China.
With the rise in laser power, there has been a phenomenal growth in the field of high power laser-plasma interaction with diverse applications, ranging from laser driven fusion and laser acceleration of charged particles to laser ablation of materials. The field has revealed a rich variety of fascinating new phenomena. Parametric coupling between lasers and plasma eigenmodes and quasi-modes gives rise to stimulated Raman, Brillouin, and Compton scattering, two-plasmon decay, and four-wave processes of filamentation, modulational, and oscillating two-stream instabilities of the laser. Nonlinear refraction gives rise to selffocusing and self-guiding of lasers over long distances in plasma and air, offsetting diffraction divergence. Laser interaction with rough metallic surfaces reveals surface-enhanced Raman scattering (SERS) where Raman scattered power from adsorbed molecules rises a million times due to surface plasmon resonance. Laser mode conversion to surface plasma waves (SPWs) on metallic surfaces has been shown to enhance the ablation yield and thin film deposition rates by orders of magnitude, making pulsed laser deposition a very attractive scheme.