PENELITIAN BAHAN PENCERAH DAN PELEMBAB KULIT DARI TANAMAN INDONESIA

The market of skin lightening product grows very fast.  This is especially true  in almost all Asian countries.  Martha Tilaar Innovation Center has found natural ingredients which function as anti oxidant and anti tyrosinase in vitro. These ingre-dients are extracted from Indonesian plants namely Lansium domesticum (LE)*) and Phyllantus niruri (PE) *). Several aspects should be considered to utilize these ingredients in cosmetic, such as, the stability of the plant materials and their safety and efficacy on human skin. The objective of this research  is to study whether these ingredients in  cosmetic preparations  have skin lightening and skin moisturizingeffects clinically. This article will describe the safety and efficacy evaluation on natu-ral ingredients extracted with ethanol from the above Indonesian plants. The safety evaluation is conducted clinically using Repeated Opened Patch Test (ROPT) and followed by Single Closed Patch Test (SCPT) in more than 50 selected healthy volun-teers. Their irritation properties on mucous membrane were evaluated using HETCAMmethod. Then, their efficacies on lightening and moisturizing were conducted in more than 26 volunteers, using Mexameter MX 16 and Corneometer CM 820. These results revealed that both extracts are safe on human skin and mucous membrane and can function as skin lightening agent.  Lansium domesticum extract also has skin moisturizing effect.Key words :  Lansium domesticum, Phyllantus niruri, lightening agent, moistur-izing agent, Asian skin, Indonesia

Spin Fluctuation Induced Dephasing in a Mesoscopic Ring

We investigate the persistent current in a hybrid Aharonov-Bohm ring - quantum dot system coupled to a reservoir which provides spin fluctuations. It is shown that the spin exchange interaction between the quantum dot and the reservoir induces dephasing in the absence of direct charge transfer. We demonstrate an anomalous nature of this spin-fluctuation induced dephasing which tends to enhance the persistent current. We explain our result in terms of the separation of the spin from the charge degree of freedom. The nature of the spin fluctuation induced dephasing is analyzed in detail.Comment: 4 pages, 4 figure

Changes in the Magnetization of a Double Quantum Dot

From accurate measurements of the energy states in a double quantum dot we deduce the change in magnetization due to single electron tunneling. As a function of magnetic field we observe crossings and anti-crossings in the energy spectrum. The change in magnetization exhibits wiggles as a function of magnetic field with maximum values of a few effective Bohr magnetons in GaAs. These wiggles are a measure of the chaotic motion of the discrete energy states versus magnetic field. Our results show good agreement with a numeric calculation but deviate significantly from semiclassical estimates.Comment: 6 pages, plus 3 figure

Lunar outpost sustaining human space exploration by utilizing in-situ resources with a focus on propellant production

Space exploration has recently witnessed a surge of renewed interest, in particular, the concept of a human mission to the Moon is increasingly being discussed by national agencies and private enterprises alike. A lunar base is commonly regarded as a good first step for humanity’s expansion beyond Earth. This paper proposes a pre-phase A study about infrastructure on the Moon surface with the capability of sustaining future human space exploration. The outpost will be relying on In-Situ Resources Utilization (ISRU) and on the support of the orbiting Deep Space Gateway (DSG), in line with the current ISECG exploration roadmap. In this context, precursor robotic missions, such as the concept proposed in the ESA-led Heracles study, and related activities on the Moon surface are considered as sources of insight and technology validation. The incremental steps necessary for setting up the Lunar outpost are discussed and analysed, both for surface and on-orbit missions. A feasibility and sustainability study is carried out for a propellant production plant, the primary purpose of which is to provide the capability of refuelling space vehicles. The design of the overall mission revolves around four main building blocks, which are analysed in detail: crew habitats, a large pressurized crew rover, ISRU facilities and a lunar spaceport. The overall mission scenario has been derived from a set of trade-off analyses that have been performed to choose the mission architecture and operations that satisfy the stakeholder expectations: the most important features of these analyses and their results are described within the paper. Regarding the timeframe, the analysed mission is expected to take place after robotic precursor expeditions, which are scheduled to launch in the 2020s. The first manned mission shall follow before 2030 with the purpose of setting up the propellant production facility, which shall be operational by 2035. The study is carried out by the 10th edition of the Specializing Master programme in SpacE Exploration and Development Systems (SEEDS) of 2017/18 at Politecnico di Torino (Italy). This work was performed in cooperation with students from ISAE-Supaero (France) and University of Leicester (UK). The project is supported by Thales Alenia Space Italy, the European Space Agency, and the Italian Space Agency