Faint warm debris disks around nearby bright stars explored by AKARI and IRSF

Context: Debris disks are important observational clues for understanding planetary-system formation process. In particular, faint warm debris disks may be related to late planet formation near 1 AU. A systematic search of faint warm debris disks is necessary to reveal terrestrial planet formation. Aims: Faint warm debris disks show excess emission that peaks at mid-IR wavelengths. Thus we explore debris disks using the AKARI mid-IR all-sky point source catalog (PSC), a product of the second generation unbiased IR all-sky survey. Methods : We investigate IR excess emission for 678 isolated main-sequence stars for which there are 18 micron detections in the AKARI mid-IR all-sky catalog by comparing their fluxes with the predicted fluxes of the photospheres based on optical to near-IR fluxes and model spectra. The near-IR fluxes are first taken from the 2MASS PSC. However, 286 stars with Ks<4.5 in our sample have large flux errors in the 2MASS photometry due to saturation. Thus we have measured accurate J, H, and Ks band fluxes, applying neutral density (ND) filters for Simultaneous InfraRed Imager for Unbiased Survey (SIRIUS) on IRSF, the \phi 1.4 m near-IR telescope in South Africa, and improved the flux accuracy from 14% to 1.8% on average. Results: We identified 53 debris-disk candidates including eight new detections from our sample of 678 main-sequence stars. The detection rate of debris disks for this work is ~8%, which is comparable with those in previous works by Spitzer and Herschel. Conclusion: The importance of this study is the detection of faint warm debris disks around nearby field stars. At least nine objects have a large amount of dust for their ages, which cannot be explained by the conventional steady-state collisional cascade model.Comment: 17 pages, 21 figures, accepted for publication in Astronomy and Astrophysic

Sugar Scrub Effects on Skin Barrier Function and Heat Retention in Low Birth Weight Infants

Objective: This investigation sought to compare changes in body heat after using a sugar scrub to bathe lowbirth weight infants (< 2,500 g), compared with those bathed using conventional baby soap, and to evaluatethe relationship between skin barrier function and changes in body heat.Design: Non-Randomized clinical trialsSetting: A neonatal intensive care unit in a university hospital in JapanParticipants: 22 Low birth weight infants for whom bathing was permittedMethods: Sebum quantity and skin temperature were each measured before and after bathing for a control groupbathed with conventional baby soap and a group bathed with a sugar scrub skin care product. Ethical approvalfor this study was obtained from Aino university of Ethics committee review board (Approval number/27)Results: The results demonstrated that both sebum quantity and skin temperature increased significantly afterbathing in the sugar scrub group compared with the baby soap group.Conclusion: Increases in sebum quantity are thought to influence the normal barrier function of skin and to helpretain skin temperature. This study suggests that the use of this skin care product can be expected to effectivelyhelp maintain body temperature in low birth weight infants, who are prone to low body temperature

Two cases of acute‐onset cystoid macular edema and serous retinal detachment associated with combined use of encorafenib and binimetinib for advanced melanoma: A possible confounding risk for drug intolerance

Abstract While combined use of BRAF/MEK inhibitors has elicited dramatic clinical efficacy in incurable melanoma, drug‐associated retinopathy has become an emerging adverse event. We present two Japanese men with advanced melanoma who developed visual impairment due to serous retinal detachments (SRDs) with cystoid macular edema (CME) immediately after initial administration of encorafenib/binimetinib, a BRAF and MEK inhibitor. One case had drug‐intolerable retinopathy on repeat dosing. Both cases were switched to another BRAF/MEK inhibitors, dabrafenib/trametinib, with no recurrence of SRDs. Co‐existing CME may be a confounding risk for the early development of SRDs with encorafenib/binimetinib therapy, providing attention during drug administration

Potential UV-Protective Effect of Freestanding Biodegradable Nanosheet-Based Sunscreen Preparations in <i>XPA</i>-Deficient Mice

Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disorder. As patients with XP are deficient in nucleotide excision repair, they show severe photosensitivity symptoms. Although skin protection from ultraviolet (UV) radiation is essential to improve the life expectancy of such patients, the optimal protective effect is not achieved even with sunscreen application, owing to the low usability of the preparations. Nanosheets are two-dimensional nanostructures with a thickness in the nanometer range. The extremely large aspect ratios of the nanosheets result in high transparency, flexibility, and adhesiveness. Moreover, their high moisture permeability enables their application to any area of the skin for a long time. We fabricated preparations containing avobenzone (BMDBM) based on freestanding poly (L-lactic acid) (PLLA) nanosheets through a spin-coating process. Although monolayered PLLA nanosheets did not contain enough BMDBM to protect against UV radiation, the layered nanosheets, consisting of five discrete BMDBM nanosheets, showed high UV absorbance without lowering the adhesive strength against skin. Inflammatory reactions in XPA-deficient mice after UV radiation were completely suppressed by the application of BMDBM-layered nanosheets to the skin. Thus, the BMDBM layered nanosheet could serve as a potential sunscreen preparation to improve the quality of life of patients with XP