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In this paper, by using Itô's formula, we study the dynamic behaviors of a stochastic human immune deficiency virus (HIV) model, which describes Acquired Immune Deficiency Syndrome (AIDS) with the effect of treatment. First, we discuss the global positivity of the solution to such a model with positive initial value. Then, we consider the limiting behavior of the solution. Moreover, we obtain the sufficient condition to guarantee the extinction of AIDS. Meanwhile, by constructing an appropriate Lyapunov function, we prove that the solution has a unique ergodic stationary distribution under a certain assumptions. Finally, we illustrate the validity of our results by numerical simulations. [ABSTRACT FROM AUTHOR]

Simple Summary: Researchers and breeders are consistently exploring better strategies to improve milk, meat, and wool production in different sheep breeds. Conventionally, sheep are grazed on unbalanced pastures that vary in their composition, which results in lower growth performance and heavy parasitic infections. The ongoing climatic changes also have a drastic impact on grazing areas, leading to severe pasture scarcity across the world. Typically, barn-fed sheep rely on hay with a small amount of grain feeding. Right now, sheep production is pacing toward indoor rearing, which demands a highly precise feeding regimen. Therefore, determining the precise protein levels in the nutrition of indoor sheep production is more critical. The current experiment was planned to evaluate the changes in the rumen metabolite profile of lactating ewes fed different dietary protein levels. Feeding sheep at higher protein levels significantly altered the metabolite profile. These metabolic findings provide insights into potentiated biomarker changes in the metabolism influenced by dietary protein levels. Diet-associated characteristics such as dietary protein levels can modulate the gut's primary or secondary metabolites, leading to effects on the productive performance and overall health of animals. Whereas fecal metabolite changes are closely associated with gut metabolome, this study aimed to see changes in the rumen metabolite profile of lactating ewes fed different dietary protein levels. For this, eighteen lactating ewes (approximately 2 years old, averaging 38.52 ± 1.57 kg in their initial body weight) were divided into three groups (n = 6 ewes/group) by following the complete randomized design, and each group was assigned to one of three low-protein (D_I), medium-protein (D_m), and high-protein (D_h) diets containing 8.58%, 10.34%, and 13.93% crude protein contents on a dry basis, respectively. The fecal samples were subjected to untargeted metabolomics using ultra-performance liquid chromatography (UPLC). The metabolomes of the sheep fed to the high-protein-diet group were distinguished as per principal-component analysis from the medium- and low-protein diets. Fecal metabolite concentrations as well as their patterns were changed by feeding different dietary protein levels. The discriminating metabolites between groups of nursing sheep fed different protein levels were identified using partial least-squares discriminant analysis. The pathway enrichment revealed that dietary protein levels mainly influenced the metabolism-associated pathways (n = 63 and 39 in positive as well as negative ionic modes, respectively) followed by protein (n = 15 and 8 in positive as well as negative ionic modes, respectively) and amino-acid (n = 14 and 7 in positive as well as negative ionic modes, respectively) synthesis. Multivariate and univariate analyses showed comparative changes in the fecal concentrations of metabolites in both positive and negative ionic modes. Major changes were observed in protein metabolism, organic-acid biosynthesis, and fatty-acid oxidation. Pairwise analysis and PCA reveal a higher degree of aggregation within the D-h group than all other pairs. In both the PCA and PLS-DA plots, the comparative separation among the D_h/D_m, D_h/D_I, and D_m/D_I groups was superior in positive as well as negative ionic modes, which indicated that sheep fed higher protein levels had alterations in the levels of the metabolites. These metabolic findings provide insights into potentiated biomarker changes in the metabolism influenced by dietary protein levels. The target identification may further increase our knowledge of sheep gut metabolome, particularly regarding how dietary protein levels influence the molecular mechanisms of nutritional metabolism, growth performance, and milk synthesis of sheep. [ABSTRACT FROM AUTHOR]

Developing non-precious metal catalysts for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is critical for Zn–air batteries. Herein, using NaCl and ammonium oxalate as templates to prepare a hierarchical porous Fe–N–C catalyst using an inorganic salt melting strategy is proposed. The prepared Fe–N–C-x catalysts have a hierarchical porous structure that increases the specific surface area, improves the exposure of a number of active sites and enhances the chance of contacting active sites. The structure change of a leaf-shaped zeolitic imidazolate framework (ZIF-L) during high-temperature pyrolysis was used to self-catalyze the growth of carbon nanotube structures, forming a structure of carbon nanotubes including Fe nanoparticles to provide additional active sites and reduce the aggregation of metal particles. From the perspective of economy and electrochemical performance, it is found that when the addition amount of NaCl and ammonium oxalate respectively is 2 g, the electrochemical performance of the ORR, OER and Zn–air batteries is better, and the preparation cost of the catalyst is more affordable. This strategy of forming hierarchical porous Fe–N–C catalysts by self-catalytic growth of Fe, N co-doped CNTs using inorganic salts provides a new design idea for the preparation of new hierarchical porous electrocatalysts. [ABSTRACT FROM AUTHOR]

MXenes suffer from severe oxidation and progressive degradation in aqueous media due to its poor chemical stability. Herein, sodium dodecyl sulfate (SDS) is employed as an efficient protectant for long‐term storage of Ti3C2Tx‐MXene aqueous dispersion. Experimental data support SDS's capability to protect oxidation‐prone sites on Ti3C2Tx nanosheets, providing extended colloidal stability of up to 213 days. Concentration‐dependent anti‐oxidation effect articulates that 1.5 mg mL−1 is deemed as an ideal SDS dose for Ti3C2Tx to achieve optimal oxidation‐resistance in aqueous solution. Additionally, a chroma strategy is developed to instantly and precisely measure the oxidation degree of Ti3C2Tx. Adsorption‐driven anti‐oxidation efficacy of SDS is further confirmed by optimized conformations with interaction energies of SDS on termination‐free and surface‐defective Ti3C2Tx through multiscale simulations. This proposed route is a step forward in broadening the horizons of experimental and theoretical investigations of MXenes with promising implications for long‐term storage and reliable applications. [ABSTRACT FROM AUTHOR]

Cr3+ activated near‐infrared (NIR) phosphors are getting unprecedented attention to fabricate the broad band NIR light emitting diodes (NIR‐LEDs) for nondestructive detection, bio‐imaging, and night vision. However, it remains a major challenge to obtain ultrabroadband NIR emitting phosphor with excellent quantum yield (QY). Here, a broadband NIR emitting phosphor Mg7Ga2GeO12:Cr3+ (MGGO: Cr3+) ranging from 600 to 1300 nm with an outstanding QY (93%) and large full width of half maximum (FWHM = 226 nm) is developed, in which the site occupancy tendency of Cr3+ in MGGO host is discussed in detail through combining the structure optimization and the first‐principles theory calculation with luminescent properties at low temperature. After that, the emission intensity of MGGO:Cr3+ is improved through partial substitution of Mg2+ by alkaline‐earth ions Ca2+, Sr2+, or Ba2+, and the luminescence enhancement mechanism is also investigated. Furthermore, the NIR pc‐LED device is fabricated by combining 450 nm blue LED chip with the brightest phosphor MGGO:Cr3+/Ba2+, and its potential applications are evaluated in the field of nondestructive detection, night vision, and bio‐imaging. [ABSTRACT FROM AUTHOR]