Hairy black holes in dilatonic Einstein-Gauss-Bonnet theory

We study black hole solutions in dilatonic Einstein-Gauss-Bonnet theory with a coupling constant $\alpha$ between the dilaton field and the Gauss-Bonnet term. In a previous study, we considered the black hole with the vanishing cosmological constant in this theory and constructed the hairy black hole solution with the negative $\alpha$. In this study, we present black hole solutions numerically with various physical properties in anti-de Sitter spacetime. We describe the procedure for constructing the black hole solutions in detail.Comment: 14 pages, 10 figures. This article is prepared for the Proceedings of the 17th Italian-Korean Symposium for Relativistic Astrophysic

Late-time Cosmology without Dark Sector but with Closed String Massless Sector

We propose to solve the dark energy problem by postulating the massless sector of closed strings. This sector constitutes the gravitational multiplet of string theory and, when applied to four-dimensional cosmology, predicts that the expansion of an open Universe defined in string frame is readily accelerating. We confront the prediction with the late-time cosmological data of Type Ia supernovae and quasar absorption spectrum, which probe the evolutions of the Hubble parameter and possibly the fine-structure constant. We report that the observations are in admirable agreement with the prediction without any dark sector. We estimate the Hubble constant, $H_{0}\simeq 71.2\pm 0.2\,\mathrm{km/s/Mpc}$.Comment: 8+9 pages, 5+8 figure

WIMPs in Dilatonic Einstein Gauss-Bonnet Cosmology

We use the Weakly Interacting Massive Particle (WIMP) thermal decoupling scenario to probe Cosmologies in dilatonic Einstein Gauss-Bonnet (dEGB) gravity, where the Gauss-Bonnet term is non-minimally coupled to a scalar field with vanishing potential. We put constraints on the model parameters when the ensuing modified cosmological scenario drives the WIMP annihilation cross section beyond the present bounds from DM indirect detection searches. In our analysis we assumed WIMPs that annihilate to Standard Model particles through an s-wave process. For the class of solutions that comply with WIMP indirect detection bounds, we find that dEGB typically plays a mitigating role on the scalar field dynamics at high temperature, slowing down the speed of its evolution and reducing the enhancement of the Hubble constant compared to its standard value. For such solutions, we observe that the corresponding boundary conditions at high temperature correspond asymptotically to a vanishing deceleration parameter q, so that the effect of dEGB is to add an accelerating term that exactly cancels the deceleration predicted by General Relativity. The bounds from WIMP indirect detection are nicely complementary to late-time constraints from compact binary mergers. This suggest that it could be interesting to use other Early Cosmology processes to probe the dEGB scenario.Comment: 30 pages, 8 figures, 1 tabl

Reduction of urate crystal-induced inflammation by root extracts from traditional oriental medicinal plants: elevation of prostaglandin D2 levels

Dried roots of the plants Acanthopanax senticosus, Angelica sinensis and Scutellaria baicalensis are used in traditional oriental medicine and reportedly possess anti-inflammatory properties. Using the murine air pouch model of inflammation, we investigated the efficacy and mode of action of an extract from these three plants in crystal-induced inflammation. Air pouches were raised on the backs of 8-week-old BALB/c mice. Mice were fed 100 mg/kg body weight of root extracts (A. senticosus:A. sinensis:S. baicalensis mixed in a ratio of 5:4:1 by weight) or vehicle only on days 3–6. Inflammation was elicited on day 6 by injecting 2 mg of monosodium urate (MSU) crystals into the pouch. Neutrophil density and IL-6 and TNF-α mRNA levels were determined in the pouch membrane, and the leukocyte count and IL-6, prostaglandin E2 (PGE2) and prostaglandin D2 (PGD2) levels were determined in the pouch exudate. Treatment with the root extracts led to a reduction in all inflammatory parameters: the leukocyte count in the pouch exudate decreased by 82%; the neutrophil density in the pouch membrane decreased by 68%; IL-6 and TNF-α mRNA levels in the pouch membrane decreased by 100%; the IL-6 concentration in the pouch fluid decreased by 50%; and the PGE2 concentration in the pouch fluid decreased by 69%. Remarkably, the concentration of the potentially anti-inflammatory PGD2 rose 5.2-fold in the pouch exudate (p < 0.005), which led to a normalization of the PGD2:PGE2 ratio. A 3.7-fold rise in hematopoietic PGD synthase (h-PGDS) mRNA paralleled this rise in PGD2 (p = 0.01)

COVID-19 Perception, Knowledge, and Preventive Practice: Comparison between South Korea, Ethiopia, and Democratic Republic of Congo

In Africa, the first confirmed case of COVID-19 was reported in Egypt on February 14, 2020. Since then, the number of cases has continued to&nbsp; increase with Ethiopia, the Democratic Republic of Congo (DRC), Nigeria, Sudan, Angola, Tanzania, Ghana, and Kenya identified as vulnerable&nbsp; countries. The present study aimed to: 1) identify differences in trust level of COVID-19 diagnosis, recent healthcare utilization experiences, and COVID-19-related knowledge, information, and prevention practices in South Korea, Ethiopia, and DRC; and 2) identify factors influencing trust level in healthcare facilities regarding COVID-19 diagnosis. The present study was cross-sectional. The questionnaire survey was conducted between May 1–14, 2020 using Google forms, and 748 respondents were included in the final analysis. The data collected were analyzed using ANOVA, post - hoc test, and binary logistic regression analysis. South Korea showed higher rate of practice for COVID-19 prevention such as hand washing, mask wearing, and etc. than Ethiopia and DRC. The results showed significant differences with the trust level being 3.129 times higher in respondents from DRC than those from Ethiopia (aOR=3.129, 95% CI: [1.884-5.196], p&lt;.000) and 29.137 times higher in respondents from South Korean than those from Ethiopia (aOR=29.137, 95% CI: [13.869-61.210], p&lt;.000). Gender, age, number of family members, healthcare utilization experience, information, and practice were significant variables. Health education expansion for information and practice about COVID-19 in Ethiopia and DRC is necessary. Keywords: COVID-19, Pandemic, Ethiopia, DRC, South Korea, Online Survey En Afrique, le premier cas confirmé de COVID-19 a été signalé en Égypte le 14 février 2020. Depuis, le nombre de cas n'a cessé d'augmenter avec l'Éthiopie, la République démocratique du Congo (RDC), le Nigéria, le Soudan, l'Angola, La Tanzanie, le Ghana et le Kenya ont été identifiés comme pays vulnérables. La présente étude visait à: 1) identifier les différences de niveau de confiance dans le diagnostic du COVID-19, les expériences récentes d'utilisation des soins de santé et les connaissances, informations et pratiques de prévention liées au COVID-19 en Corée du Sud, en Éthiopie et en RDC; et 2) identifier les facteurs influençant le niveau de confiance dans les établissements de santé concernant le diagnostic du COVID-19. La présente étude était transversale. L'enquête par questionnaire a été menée du 1er au 14 mai 2020 à l'aide de formulaires Google, et 748 répondants ont été inclus dans l'analyse finale. Les données collectées ont été analysées en utilisant une analyse ANOVA, un test post-hoc et une analyse de régression logistique binaire. La Corée du Sud a montré un taux de pratique plus élevé pour la prévention du COVID-19, comme le lavage des mains, le port d'un masque, etc. que l'Éthiopie et la RDC. Les résultats ont montré des différences significatives, le niveau de confiance étant 3,129 fois plus élevé chez les répondants de RDC que chez ceux d'Éthiopie (aOR = 3,129, IC à 95%: [1,884-5,196], p &lt;.000) et 29,137 fois plus élevé chez les répondants sud-coréens que ceux d'Éthiopie (aOR = 29,137, IC à 95%: [13,869-61,210], p &lt;.000). Le sexe, l'âge, le nombre de membres de la famille, l'expérience d'utilisation des soins de santé, l'information et la pratique étaient des variables importantes. L'élargissement de l'éducation sanitaire pour l'information et la pratique du COVID-19 en Éthiopie et en RDC est nécessaire. Mots-clés: COVID-19, Pandémie, Éthiopie, RDC, Corée du Sud, Enquête en lign

A Herbal Formula HT051, a Combination of Pueraria lobata

Menopause is strongly associated with an increased risk of metabolic dysfunctions due to the decline in estrogen. Here, we hypothesized that dietary HT051, containing the roots of Pueraria lobata and Rehmannia glutinosa, has beneficial effects on ovariectomized (OVX) rats by regulating lipid metabolism. Forty-eight female Sprague-Dawley rats were randomly divided into 4 groups: sham-operated (Sham), OVX, OVX with low-dose HT051 supplementation, and OVX with high-dose HT051 supplementation. The rats were fed with a modified AIN-93G diet or an HT051-containing modified AIN-93G diet for 8 weeks. Body weight, fat mass, and serum levels of total cholesterol, triglyceride, glucose, alanine transaminase, and aspartate transaminase decreased in HT051-fed OVX rats. Dietary HT051 supplementation significantly decreased the mRNA expression of lipogenesis-related genes, including sterol regulatory element-binding protein 1c and fatty acid synthase, and increased the mRNA expression of β-oxidation-related genes, including peroxisome proliferator-activated receptor and carnitine palmitoyl transferase 1 in the liver of OVX rats. Moreover, the expression of genes involved in adipogenesis and inflammation was significantly lower in the adipose tissue of OVX rats fed with HT051 than in the OVX group. These findings suggest that HT051 may be a potential natural alternative for the management of postmenopausal metabolic dysfunctions

Effects of Huang Bai (Phellodendri Cortex) and Three Other Herbs on GnRH and GH Levels in GT1–7 and GH3 Cells

The present study was to evaluate the effects of Huang Bai, Zhi Mu, Mai Ya, and Xia Ku Cao on hormone using the GT1–7 and GH3 cells. The GT1–7 and GH3 cell lines were incubated with DW; DMSO; and 30, 100, or 300 μg/mL of one of the four extract solutions in serum-free media for 24 hours. The MTT assay was performed to determine the cytotoxicity of the four herbs. The GT1–7 and GH3 cells were incubated in DW, estradiol (GT1–7 only), or noncytotoxic herb solutions in serum-free medium for 24 hours. A quantitative RT-PCR and western blot were performed to measure the GnRH expression in GT1–7 cells and GH expression in GH3 cells. Huang Bai, Zhi Mu, Xia Ku Cao, and Mai Ya inhibited the GnRH mRNA expression in GT1–7 cells, whereas Huang Bai enhanced GH mRNA expression in GH3 cells. Additionally, Xia Ku Cao inhibited GnRH protein expression in GT1–7 cells and Huang Bai promoted GH protein expression in GH3 cells. The findings suggest that Huang Bai can delay puberty by inhibiting GnRH synthesis in the hypothalamus while also accelerating growth by promoting GH synthesis and secretion in the pituitary

Microstructure and Electrochemical Behaviors of Equiatomic TiMoVCrZr and Ti-rich TiMoVCrZr High-Entropy Alloys for Metallic Biomaterials

The present study investigated various thermodynamic parameters, microstructures and electrochemical behaviors of TiMoVCrZr and Ti-rich TiMoVCrZr high-entropy alloys (HEAs) prepared by vacuum arc remelting. The microstructures of the alloys were analyzed using X-ray diffraction (XRD) analysis, field emission scanning electron microscopy (FE-SEM), and potentiodynamic polarization tests. The determined thermodynamic values of the Ω-parameter and the atomic size difference (δ) for the HEAs were determined to be in the range of Ω ≥ 1.1, and δ ≤ 6.6% with valance electron configuration (VEC) ≤ 5.0, suggesting the HEAs were effective at forming solid solutions. XRD patterns of the equiatomic Ti20 Mo20 V20 Cr20 Zr20 HEA revealed four phases consisting of the body centered cubic1 (BCC1 ), BCC2 , hexagonal close-packed (HCP), and intermetallic compound Cr2 Zr phases. Three phases were observed in the XRD patterns of Ti-rich Ti40 Mo15 V15 Cr15 Zr15 (BCC, HCP, and Cr2 Zr) and a single BCC phase was observed in Ti-rich Ti60 Mo10 V10 Cr10 Zr10 HEAs. The backscattered-electron (BSE) images on the equiatomic Ti20 Mo20 V20 Cr20 Zr20 HEA revealed BCC and HCP phases with Cr2 Zr precipitates, suggesting precipitation from the HCP solid solution during the cooling. The micro-segregation of Ti-rich Ti60 Mo10 V10 Cr10 Zr10 HEAs appeared to decrease remarkably. The alloying elements in the HEAs were locally present and no phase changes occurred even after additional HIP treatment. The lowest current density obtained in the polarization potential test of Ti-rich Ti40 Mo15 V15 Cr15 Zr15 HEA was 7.12×10-4 mA/cm2 was obtained. The studied TiMoVCrZr HEAs showed improved corrosion characteristics as compared to currently available joint replacement material such as ASTM F75 alloy