The Argus II Retinal Prosthesis System

The field of retinal prosthetics has seen significant advances in the past 3 decades. Encouraging results from different groups have shown coarse objective functional improvement, using a range of technological and surgical approaches. The Argus II retinal prosthesis system was the first of its kind to receive regulatory approval for commercial use in Europe and the USA. The device is designed to replicate the function of photoreceptors in converting visual information into electrical neural signals in patients with profound visual loss secondary to degenerative retinal disease. Results from a phase II study of 30 patients have demonstrated improved performance in basic tests of visual function, object recognition, letter reading, prehension, orientation and mobility tasks. It is now the most widely implanted retinal prosthetic device worldwide. This chapter provides an overview of the requirements of a retinal prosthetic system, the results from the Argus II device to date, and an insight into some of the challenges and future directions of visually restorative therapies

Photovoltaic industry in Uganda : local manufacturers of PV components and imported products - efficiencies and national standards

Izael Pereira Da Silva, Edward Kyalimpa - Renewable energyEnergy is a key factor for the development of a country. In many remote areas of the third world with good insolation such as Uganda, photovoltaic is one of the most suitable ways of providing energy to rural areas. The government of Uganda is actually pushing what is called “Rural Electrification, Strategy and Plan” to foster a massive purchase and use of Solar Home Systems. Nonetheless, in order to spread photovoltaic technology, one of the main difficulties of a country is the lack of proper framework for importation of the components, maintenance, and data on technical performance of these components. This paper does a national survey on local manufacturers of deep-cycle batteries, charge controllers, lights and inverters; panels are not available as yet and it won’t be in a foreseeable future. Given the importers possibilities, it also does an economic analysis comparing products from China, India, Europe and USA, taking into account the actual governmental position in terms of taxes on photovoltaic products. Some valuable data are presented on the experiences of NGO’s and local communities; how successful have they been, problems they face, etc. The concern about quality and the idea of providing the costumer with a reliable product drove the authors also to analyse the documents of the Uganda National Bureau of Standard establishing national standards and minimal warranty for all components related with solar energy and write some few considerations. Finally, taking advantage of other countries experiences a specificEnergy is a key factor for the development of a country. In many remote areas of the third world with good insolation such as Uganda, photovoltaic is one of the most suitable ways of providing energy to rural areas. The government of Uganda is actually pushing what is called “Rural Electrification, Strategy and Plan” to foster a massive purchase and use of Solar Home Systems. Nonetheless, in order to spread photovoltaic technology, one of the main difficulties of a country is the lack of proper framework for importation of the components, maintenance, and data on technical performance of these components. This paper does a national survey on local manufacturers of deep-cycle batteries, charge controllers, lights and inverters; panels are not available as yet and it won’t be in a foreseeable future. Given the importers possibilities, it also does an economic analysis comparing products from China, India, Europe and USA, taking into account the actual governmental position in terms of taxes on photovoltaic products. Some valuable data are presented on the experiences of NGO’s and local communities; how successful have they been, problems they face, etc. The concern about quality and the idea of providing the costumer with a reliable product drove the authors also to analyse the documents of the Uganda National Bureau of Standard establishing national standards and minimal warranty for all components related with solar energy and write some few considerations. Finally, taking advantage of other countries experiences a specific solar home system is designed for Uganda users

Cryo-EM reveals the conformation of a substrate analogue in the human 20S proteasome core

The proteasome is a highly regulated protease complex fundamental for cell homeostasis and controlled cell cycle progression. It functions by removing a wide range of specifically tagged proteins, including key cellular regulators. Here we present the structure of the human 20S proteasome core bound to a substrate analogue inhibitor molecule, determined by electron cryo-microscopy (cryo-EM) and single-particle analysis at a resolution of around 3.5 Å. Our map allows the building of protein coordinates as well as defining the location and conformation of the inhibitor at the different active sites. These results open new prospects to tackle the proteasome functional mechanisms. Moreover, they also further demonstrate that cryo-EM is emerging as a realistic approach for general structural studies of protein–ligand interactions

Energy efficient building envelope designs for institutional buildings in East Africa

Izael Da Silva; Edward Baleke Ssekulima - International conference Towards sustainable energy solutions for the developing worldTo date, insufficient attention has been afforded to the design and energy performance of Institutional buildings in East Africa. As a result most Institutional buildings in the region do not incorporate the issue of energy efficiency at the design, construction and utilization stages. Institutions are amongst the major consumers of energy in any country most of which is utilized within buildings, thus a thorough critique of the building envelope is necessary to reduce energy wastage within them. The aim of this paper is to present findings of the comparative study carried out on Institutional buildings at Strathmore University-Nairobi, Kenya and Makerere University-Kampala, Uganda. The study mainly considered the effect of building envelope designs and orientation to the energy consumption of the buildings. ECOTECT, a Building energy performance analysis tool was employed to quantify the effect of both the conventional and Energy Efficient Building Envelopes to the overall energy consumption of the buildings. The research findings show that the overall energy consumption of Institutional buildings could easily be reduced by about 40% through the design of envelopes suited to the micro-climate of the particular site, proper selection of construction materials vis-a-vis their thermal performance, extensive use of day-lighting, wise utilization of water and good building waste management systems as well as utilization of Energy Efficient Appliances within the building. The study also revealed that integration of a Building Management System would significantly reduce resource utilization within the building.To date, insufficient attention has been afforded to the design and energy performance of Institutional buildings in East Africa. As a result most Institutional buildings in the region do not incorporate the issue of energy efficiency at the design, construction and utilization stages. Institutions are amongst the major consumers of energy in any country most of which is utilized within buildings, thus a thorough critique of the building envelope is necessary to reduce energy wastage within them. The aim of this paper is to present findings of the comparative study carried out on Institutional buildings at Strathmore UniversityNairobi, Kenya and Makerere University-Kampala, Uganda. The study mainly considered the effect of building envelope designs and orientation to the energy consumption of the buildings. ECOTECT, a Building energy performance analysis tool was employed to quantify the effect of both the conventional and Energy Efficient Building Envelopes to the overall energy consumption of the buildings. The research findings show that the overall energy consumption of Institutional buildings could easily be reduced by about 40% through the design of envelopes suited to the micro-climate of the particular site, proper selection of construction materials vis-avis their thermal performance, extensive use of daylighting, wise utilization of water and good building waste management systems as well as utilization of Energy Efficient Appliances within the building. The study also revealed that integration of a Building Management System would significantly reduce resource utilization within the building

Poly[[μ2-1,4-bis­(imidazol-1-ylmeth­yl)benzene]bis­(μ4-cyclo­hexane-1,4-dicarboxyl­ato)dicobalt(II)]

In the title compound, [Co2(C8H10O4)2(C14H14N4)]n, the two CoII atoms are both five-coordinated by four carboxyl­ate O atoms, derived from two different cyclo­hexane-1,4-dicarboxyl­ate (chdc) ligands, and an N atom, derived from one end of a 1,4-bis­(imidazol-1-ylmeth­yl)benzene mol­ecule (1,4-bix), in a distorted square-pyramidal environment. Each end of the chdc ligand links pairs of CoII atoms into a paddle-wheel assembly, i.e. Co2(O2CR′)4; these are connected into rows because of the bridging nature of the chdc ligands, and the rows are further connected into a two-dimensional layer through the 1,4-bix ligands. The 1,4-bix ligand, which is disposed about a centre of inversion, is disorderd. Two positions were discerned for the –CH2(C6H4)CH2– residue, with the major component having a site-occupancy factor of 0.512 (9)