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BACKGROUND: The mainstay of mild to moderate acne treatment is topical antibiotics. A new combination of 2% erythromycin and 1% bifonazole was tested in a double-blind trial against erythromycin alone. METHODS: A total of 207 acne patients were recruited into the study and 157 (76%) completed the full trial protocol of 12 weeks of treatment. In all, 74 patients applied the combination solution (erythromycin + bifonazole) once a day and 83 patients applied erythromycin solution twice a day. Outcome parameters measured were lesion-count (open and closed comedones, papules and pustules) and acne grading using the Cook's acne scale, carried out at the initial visit, and at the 4, 8 and 12-week follow-up visits. RESULTS: Both treatment groups improved significantly over baseline and showed continuous improvement throughout the trial, with the erythromycin + bifonazole group showing better improvement than the erythromycin group. At the end of 12 weeks, open comedones, closed comedones, papules and pustules were reduced by 57%, 61%, 73% and 83% respectively in the erythromycin + bifonazole group, compared to 47%, 60%, 61% and 72% in the erythromycin group (P-values of 0.04, 0.007, 0.0017 and 0.056, respectively). Acne grading improved by 44.8% in the erythromycin + bifonazole group compared to a 34.7% improvement in the erythromycin group (P-values of 0.047). Transient local adverse effects occurred in both groups leading to five patients dropping out, four of them from the combination group. CONCLUSION: Topical treatment of acne with a combination of erythromycin 2% and bifonazole 1% once daily is a safe and effective treatment that has a modest but significant advantage over treatment with erythromycin 2% alone twice daily. (J Dermatol Treat (2000) 11: 247-251). [ABSTRACT FROM AUTHOR]

In recent years atomic oxygen (AO) has become a major challenge for the space community. AO is the most dominant species of the residual atmosphere in low Earth orbit (LEO). In addition, AO was found at the top of the Venusian and Martian atmospheres. As a result of exposure to AO, organic space-facing materials erode, leading to changes in their roughness, thermo-optical properties, and mass loss. In the past years, there has been a growing interest in very low Earth orbit missions, below an altitude of 350 km, where AO density and thus, AO flux, are extremely high. At these low altitudes, material degradation by AO erosion poses a great risk to the integrity of any space-facing material, unless well protected. As such, measuring the AO flux and the consequential material erosion by AO, in real-time while under actual space conditions, are of great interest to the space community. Thus, in this work we present real-time AO material erosion measurements that were conducted, for the first-time in LEO, using the on-orbit material degradation detector (ORMADD). The ORMADD is a low-cost and simple to operate detector, comprised of photovoltaic cells coated with semi-transparent AO sensitive coatings. Two ORMADDs were integrated on TAUSAT-1, a 3U CubeSat, deployed into LEO from the international space station. The first ORMADD was coated with a thin amorphous-carbon coating and the second was covered with a thick pyrolytic Kapton film. Using ORMADD, we were able to follow the erosion of the coatings in real-time conditions and calculate the AO flux in TAUSAT-1 orbit. The average in-orbit flux, derived from ORMADD data, was found to be comparable to the theoretical average AO flux calculated by the space environment information system (SPENVIS) software. This work demonstrates the abilities of ORMADD as a space environment detector, as well as a space material degradation research instrument. • Atomic oxygen measurements were done by the on-orbit material degradation detector. • The on-orbit material degradation detector is based on coated photovoltaic cells. • The erosion of the coating was measured and the atomic oxygen flux was derived. • Atomic oxygen flux was also simulated by the SPENVIS simulation software. • Space measured atomic oxygen flux is comparable to the flux simulated by SPENVIS. [ABSTRACT FROM AUTHOR]

The QB50 mission is a satellite constellation designed to carry out measurements at between 200–380 km altitude in the ionosphere. The multi-needle Langmuir probe (m-NLP) instrument has been mounted on board eleven QB50 satellites in order to characterize ambient plasma. The distinct feature of this instrument is its capability of measuring the plasma density at high spatial resolution without the need to know the electron temperature or the spacecraft potential. While the instrument has been deployed on many sounding rockets, the QB50 satellites offer the opportunity to demonstrate the operation of the instrument in low-earth orbit (LEO). This paper provides a brief review of the m-NLP instrument specifically designed for the QB50 mission and the case studies of the instrument's performance on board the Ex-Alta 1 and Hoopoe satellites. The system has also been functionally verified in a plasma chamber at the European Space Research and Technology Center (ESTEC). Although the QB50 mission's scientific goals have not been reached yet and some uncertainties still remain, there are some optimistic in-orbit preliminary results which could be helpful for the system improvement in future campaigns. Particularly, the electron emitter as part of the m-NLP science unit has demonstrated its capability in the plasma chamber and in orbit to mitigate spacecraft charging effects. [ABSTRACT FROM AUTHOR]