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In this paper, we prove that the only almost Kenmotsu (k , μ) ′ -manifold of dimension three admitting a non-Killing conformal vector field is the product space ℍ 2 (− 4) × ℝ. All conformal vector fields on this product are determined. [ABSTRACT FROM AUTHOR]

In this article, pseudoparallel submanifolds for almost Kenmotsu (κ, μ, ν) --space are investigated. The almost Kenmotsu (κ, μ, ν) --space is considered on the concircular curvature tensor. Submanifolds of these manifolds with properties such as concircular pseudoparallel, concircular 2--pseudoparallel, concircular Ricci generalized pseudoparallel, and concircular 2--Ricci generalized pseudoparallel has been characterized. Necessary and sufficient conditions are given for the invariant submanifolds of almost Kenmotsu (κ, μ, ν) --space to be total geodesic according to the behavior of the κ, μ, ν functions. [ABSTRACT FROM AUTHOR]

We have investigated 4-μm-band SO 3 absorption lines for in situSO 3 detection using a mid-infrared laser source based on difference frequency generation in a quasi-phase-matched LiNbO 3 waveguide. In the wavelength range of 4.09400-4.10600 μm, there were strong SO 3 absorption lines. The maximum absorption coefficient at a concentration of 170 ppmv was estimated to be about 3.2×10 -5   cm -1 at a gas temperature of 190°C. In coexistence with H 2 O, the reduction of the SO 3 absorption peak height was observed, which was caused by sulfuric acid formation. We discuss a method of using an SO 3 equilibrium curve to derive the total SO 3 molecule concentration.

The object of the present paper is to study the symmetric and skewsymmetric properties of a second order parallel tensor on paracontact metric (k, µ)- spaces and almost β-para-Kenmotsu (k, µ)-spaces. In this paper, we prove that if there exists a second order symmetric parallel tensor on a paracontact metric (k, µ)- space M, then either M is locally isometric to a product of a flat n + 1-dimensional manifold and an n-dimensional manifold of constant sectional curvature −4, or the second order parallel tensor is a constant multiple of the associated metric tensor g of M2n+1. If there is a second order parallel tensor on an almost β-para-Kenmotsu (k, µ)-space with k ≠ 0, then it is a constant multiple of the associated metric tensor g of M2n+1. [ABSTRACT FROM AUTHOR]

The skin is a barrier that protects the human body against environmental factors (physical, including solar radiation, chemicals, and pathogens). The integrity and, consequently, the effective metabolic activity of skin cells is ensured by the cell membrane, the important structural and metabolic elements of which are phospholipids. Phospholipids are subject to continuous transformation, including enzymatic hydrolysis (with the participation of phospholipases A, C, and D) to free polyunsaturated fatty acids (PUFAs), which under the influence of cyclooxygenases (COX1/2), lipoxygenases (LOXs), and cytochrome P450 (CYPs P450) are metabolized to various classes of oxylipins, depending on the type of PUFA being metabolized and the enzyme acting. The most frequently analyzed oxylipins, especially in skin cells, are eicosanoids, which are derivatives of arachidonic acid (AA). Their level depends on both environmental factors and endogenous metabolic disorders. However, they play an important role in homeostasis mechanisms related to the structural and functional integrity of the skin, including maintaining redox balance, as well as regulating inflammatory processes arising in response to endogenous and exogenous factors reaching skin cells. Therefore, it is believed that dysregulation of eicosanoid levels may contribute to the development of skin diseases, such as psoriasis or atopic dermatitis, which in turn suggests that targeted control of the generation of specific eicosanoids may have diagnostic significance and beneficial therapeutic effects. This review is the first systemic and very detailed approach presenting both the causes and consequences of changes in phospholipid metabolism leading to the generation of eicosanoids, changes in the level of which result in specific metabolic disorders in skin cells leading to the development of various diseases. At the same time, existing literature data indicate that further detailed research is necessary to understand a clear relationship between changes in the level of specific eicosanoids and the pathomechanisms of specific skin diseases, as well as to develop an effective diagnostic and therapeutic approach. [ABSTRACT FROM AUTHOR]

Background: Over time, the prevalence of allergic rhinitis (AR) has surged due to various risk factors, notably attributed to global urbanization, rendering heightened levels of pollutants, including traffic-related emissions and particulate matter. About 25% of the global children population and 40% of the adult population were reported with AR. Even though AR is recognized as a systemic inflammatory disease, it often results in diverse other comorbidities, such as dermatitis, sinusitis, conjunctivitis, and otitis, requiring extensive and expensive treatment. Objectives: We assessed the effectiveness of iridoid glucoside catalpol against AR in a mouse model. Catalpol is recommended in traditional Chinese medicine to treat diverse acute and chronic diseases. Materials and Methods: AR was induced in mice with an ovalbumin-sensitized AR model and treated with 10 and 20 mg of catalpol. Nasal severity scoring was performed to confirm the AR induction in mice. Allergic mediators immunoglobulin E (IgE) and histamine were quantified in the serum to assess the anti-allergic response of catalpol. In nasal lavage fluid (NALF), the inflammatory mediators IgE Ab, prostaglandin D2, leukotriene C4, eosinophil cationic protein (ECP), and pro-inflammatory cytokines were measured to analyze the anti-inflammatory potency of catalpol. The binding capacity of nuclear factor-kappa B (NF-κB) to DNA was evaluated to assess the catalpol inhibitory potency against NF-κB-mediated inflammation in AR mice. To confirm the ameliorative potency of catalpol in AR mice, a histopathological analysis of nasal mucosa was performed. Results: Catalpol treatment significantly decreased the nasal symptoms and reduced the allergic mediators in the serum of experimental animals. It effectively inhibited the synthesis of inflammatory mediators, ECP, and pro-inflammatory cytokines in the NALF, and also suppressed the NF-κB DNA-binding activity in AR mice. The decrease in ciliary loss, goblet cells, eosinophil infiltration, and vascular congestion observed with our nasal mucosa histopathological analysis confirmed the ameliorative potency of catalpol. Conclusion: Our findings have proven catalpol inhibits NF-κB-mediated inflammatory response in AR mice. With further analysis, a potent natural compound, catalpol, can be formulated as a drug to treat AR. [ABSTRACT FROM AUTHOR]

The present article deals with static perfect fluid spacetimes on f-Kenmotsu 3-manifolds. At first, we demonstrate if a 3-dimensional f-Kenmotsu manifold with constant scalar curvature as the spatial factor of a static perfect fluid spacetime, then either it is a space of constant sectional curvature or g r a d ψ is pointwise collinear with ξ and the warping function of the static perfect fluid spacetime is given by ψ = k 1 t + k 2 , k 1 ≠ 0 . As a result, we establish that if a cosymplectic manifold of dimension three with constant scalar curvature is the spatial factor of a static perfect fluid spacetime, then either it is flat or, the manifold becomes a space of constant sectional curvature. Next, we show that under certain restrictions if a 3-dimensional f-Kenmotsu manifold is the spatial factor of a static perfect fluid spacetime, then either the manifold is a space of constant sectional curvature or, the manifold is locally isometric to either the flat Euclidean space R 3 or the Riemannian product R × M 2 (c) , where M 2 (c) represents a Kahler surface with constant curvature c ≠ 0 , provided ξ ψ = 0 and ξ f ~ = 0 . Lastly, we have cited an example of an f-Kenmotsu manifold to validate our result. [ABSTRACT FROM AUTHOR]