An Overview of Marketing of Ghana Natural Products

The study finds strong correlations between natural products business performance and the impeding factors. The impediments include access to finance and markets, lack of herbal market information especially relating to external markets. Additionally, there is lack of processing capacity, while at the same time most if not all the natural products business operators lack technical training relating to product handling. However, there is big potential for success, the top ten traded natural products, may be exploited initially, both domestically and for export market, given range of perceived use. The constraints identified require concerted efforts from all stakeholders to recognize the importance of this sub-sector in providing opportunities to successful development.Marketing,

Double di ffential fragmentation cross sections measurements of 95 MeV/u 12C on thin targets for hadrontherapy

During therapeutic treatment with heavy ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, an accurate prediction on the fluences of these secondary fragments is necessary. Nowadays, a very limited set of double di ffential carbon fragmentation cross sections are being measured in the energy range used in hadrontherapy (40 to 400 MeV/u). Therefore, new measurements are performed to determine the double di ffential cross section of carbon on di erent thin targets. This work describes the experimental results of an experiment performed on May 2011 at GANIL. The double di ffential cross sections and the angular distributions of secondary fragments produced in the 12C fragmentation at 95 MeV/u on thin targets (C, CH2, Al, Al2O3, Ti and PMMA) have been measured. The experimental setup will be precisely described, the systematic error study will be explained and all the experimental data will be presented.Comment: Submitted to PR

Comparison of two analysis methods for nuclear reaction measurements of 12C +12C interactions at 95 MeV/u for hadrontherapy

During therapeutic treatment with heavier ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, the accuracy must be higher than ($\pm$3% and$\pm$1 mm). Therefore, measurements are performed to determine the double differential cross section for different reactions. In this paper, the analysis of data from 12C +12C reactions at 95 MeV/u are presented. The emitted particles are detected with \DeltaEthin-\DeltaEthick-E telescopes made of a stack of two silicon detectors and a CsI crystal. Two different methods are used to identify the particles. One is based on graphical cuts onto the \DeltaE-E maps, the second is based on the so-called KaliVeda method using a functional description of \DeltaE versus E. The results of the two methods will be presented in this paper as well as the comparison between both

Antioxidant, antibacterial, and anti-SARS-CoV Activity of Commercial Products of \u3cem\u3eXylopia\u3c/em\u3e (\u3cem\u3eXylopia aethiopica\u3c/em\u3e)

Xylopia aethiopica (Annonaceae) is a spice and medicinal plant that grows wild in many West African countries (from Liberia to Nigeria) and is locally known as Guinea pepper, grains of Selim, hwentia and uda. The dried fruits are used as a flavoring for soups and traditionally in decoctions as an analgesic and anti-inflammatory, as well as a treatment for infections. The medicinal properties of the fruits are associated with the presence of phenolics and essential oil constituents. We studied the total phenols, total flavonoids, and antioxidant activity in different X. aethiopica extracts using spectrophotometry. We found variation in total phenolic and flavonoids and antioxidant capacity between different samples and different extraction solvents. Antibacterial activity against Escherichia coli and Bacillus subtilis were evaluated using a spectrophotometric assay and Kirby-Bauer test. Additionally, a pseudoviral cell-based assay was used to test the antiviral activity against severe acute respiratory syndrome coronaviruses (SARS-CoV-1 and SARS-CoV-2). High total phenolic and flavonoid content was correlated with high antioxidant capacity. Results of antibacterial tests indicated that one Xylopia extract potentially has strong antibacterial activity against gram-positive bacteria B. subtilis. The pseudoviral assay showed moderate antiviral activity against SARS-CoV-1 and SARS-CoV-2

Learning to Communicate: A Machine Learning Framework for Heterogeneous Multi-Agent Robotic Systems

We present a machine learning framework for multi-agent systems to learn both the optimal policy for maximizing the rewards and the encoding of the high dimensional visual observation. The encoding is useful for sharing local visual observations with other agents under communication resource constraints. The actor-encoder encodes the raw images and chooses an action based on local observations and messages sent by the other agents. The machine learning agent generates not only an actuator command to the physical device, but also a communication message to the other agents. We formulate a reinforcement learning problem, which extends the action space to consider the communication action as well. The feasibility of the reinforcement learning framework is demonstrated using a 3D simulation environment with two collaborating agents. The environment provides realistic visual observations to be used and shared between the two agents.Comment: AIAA SciTech 201