Catamenial dermatoses associated with autoimmune, inflammatory, and systemic diseases: A systematic review,.

Background:Sex hormones are important in female sexual physiology, growth, and homeostasis. Through skin receptors, sex hormones contribute to the dermatologic pathology known as catamenial dermatoses. Objective:This study aims to summarize the literature on catamenial dermatoses and menses-induced exacerbations of chronic dermatoses. Methods:This systematic review used the PRISMA method. PubMed was searched using the terms "menses" and "skin" in July 2018, and an assessment was conducted of the relevant literature on skin diseases related to non-pathologic menstruation, such as polycystic ovarian syndrome. Pathology associated with androgenetic acne was excluded from the study. Results:A total of 102 studies with 1269 female patients were included. The most commonly reported primary catamenial dermatoses were autoimmune progesterone dermatitis and autoimmune estrogen dermatitis. The most commonly reported chronic skin disorders exacerbated by menses were psoriasis, Behcet's disease, and eczematous dermatoses. Conclusion:Physicians should be aware of the nature of catamenial dermatoses and their presentation with normal sexual physiology. Patients with chronic dermatoses should be appropriately counseled on menstruation-related exacerbations. Further research needs to be conducted to determine the interplay between immune regulation and sex hormones in catamenial dermatoses and to elucidate effective therapies

Measurement of impulse peak insertion loss from two acoustic test fixtures and four hearing protector conditions with an acoustic shock tube

Impulse peak insertion loss (IPIL) was studied with two acoustic test fixtures and four hearing protector conditions at the E-A-RCAL Laboratory. IPIL is the difference between the maximum estimated pressure for the open-ear condition and the maximum pressure measured when a hearing protector is placed on an acoustic test fixture (ATF). Two models of an ATF manufactured by the French-German Research Institute of Saint-Louis (ISL) were evaluated with high-level acoustic impulses created by an acoustic shock tube at levels of 134 decibels (dB), 150 dB, and 168 dB. The fixtures were identical except that the E-A-RCAL ISL fixture had ear canals that were 3 mm longer than the National Institute for Occupational Safety and Health (NIOSH) ISL fixture. Four hearing protection conditions were tested: Combat Arms earplug with the valve open, ETYPlugs ® earplug, TacticalPro headset, and a dual-protector ETYPlugs earplug with TacticalPro earmuff. The IPILs measured for the E-A-RCAL fixture were 1.4 dB greater than the National Institute for Occupational Safety and Health (NIOSH) ISL ATF. For the E-A-RCAL ISL ATF, the left ear IPIL was 2.0 dB greater than the right ear IPIL. For the NIOSH ATF, the right ear IPIL was 0.3 dB greater than the left ear IPIL

Experimental Investigation of the Acoustic Attenuation by Monolithic Polyurea Aerogels

Aerogels are lightweight, porous nanostructured materials with exceptional thermal insulation properties. the most widely studied aerogel variety is based on silica; however, recent advances in all-polymer aerogels have resolved fragility issues and render them viable alternatives. in particular, polyurea aerogels can be synthesized in a single environmentally friendly step from inexpensive triisocyanates and water over a wide range of densities. Reasoning that the nanoporous characteristics of polyurea aerogels could be accompanied by high, structure-dependent acoustic attenuation, this work investigates the acoustic properties of polyurea aerogels with emphasis on their acoustic attenuation. Conventional materials with high acoustic damping capabilities typically have relatively high densities or are bulky. in applications where weight and volume are at a premium, polyurea aerogels may potentially provide a solution where traditional materials fail. Using a three-microphone impedance tube method, this work experimentally investigates the propagation coefficient of several monolithic polyurea aerogels at different densities. in contrast to traditional porous materials, polyurea aerogels demonstrate very high acoustic attenuation and therefore show promise for a wide range of applications. This paper discusses experimental results and addresses challenges in the measurement of acoustic properties with high attenuation materials

Catamenial Hyperpigmentation: A Review.

BACKGROUND: Changes in skin pigmentation patterns related to the fluctuation of estrogen receptors and progesterone receptors during menstruation, also known as catamenial hyperpigmentation, have been reported in several studies. OBJECTIVE: We sought to summarize the literature on catamenial skin hyperpigmentation and menses-induced exacerbations of skin pigmentation disorders. METHODS: We searched PubMed/MEDLINE and the Cochrane Skin database with the search terms menses and pigment, estrogen and pigment, progesterone and pigment, and hyperpigmentation and menses, then assessed the relevant literature on skin diseases related to nonpathological menstruation. RESULTS: The most commonly reported primary catamenial hyperpigmentation disorders are postinflammatory hyperpigmentation (PIH) after laser therapy and ultraviolet sensitivity (UV). The most reported chronic skin pigmentation exacerbated by menses is melasma. The literature detailing catamenial hyperpigmentation is limited to cross-sectional studies, experimental studies, surveys, review articles, case reports, and small trials, leading to a lower level of evidence. CONCLUSION: Our review of the literature revealed that the most common catamenial hyperpigmentation is melasma. We also found a reported higher risk of PIH after laser therapies and UV sensitivity. Estrogen and progesterone are two of the major factors responsible for catamenial hyperpigmentation of the skin. Generally, the changes happen in the luteal phase of the menstrual cycle when the serum levels of sex hormones are at their peak. Although the exact balance of influence is controversial, most recent studies indicate that estrogen has a more prominent role than progesterone in inducing hyperpigmentation