Wireless Networks with Energy Harvesting and Power Transfer: Joint Power and Time Allocation

In this letter, we consider wireless powered communication networks which could operate perpetually, as the base station (BS) broadcasts energy to the multiple energy harvesting (EH) information transmitters. These employ “harvest then transmit” mechanism, as they spend all of their energy harvested during the previous BS energy broadcast to transmit the information towards the BS. Assuming time division multiple access (TDMA), we propose a novel transmission scheme for jointly optimal allocation of the BS broadcasting power and time sharing among the wireless nodes, which maximizes the overall network throughput, under the constraint of average transmit power and maximum transmit power at the BS. The proposed scheme significantly outperforms “state of the art” schemes that employ only the optimal time allocation. If a single EH transmitter is considered, we generalize the optimal solutions for the case of fixed circuit power consumption, which refers to a much more practical scenario.

A Combined Molecular Cloning and Mass Spectrometric Method to Identify, Characterize, and Design Frenatin Peptides from the Skin Secretion of Litoria infrafrenata

Amphibian skin secretions are unique sources of bioactive molecules, particularly bioactive peptides. In this study, the skin secretion of the white-lipped tree frog (Litoria infrafrenata) was obtained to identify peptides with putative therapeutic potential. By utilizing skin secretion-derived mRNA, a cDNA library was constructed, a frenatin gene was cloned and its encoded peptides were deduced and confirmed using RP-HPLC, MALDI-TOF and MS/MS. The deduced peptides were identified as frenatin 4.1 (GFLEKLKTGAKDFASAFVNSIKGT) and a post-translationally modified peptide, frenatin 4.2 (GFLEKLKTGAKDFASAFVNSIK.NH2). Antimicrobial activity of the peptides was assessed by determining their minimal inhibitory concentrations (MICs) using standard model microorganisms. Through studying structure–activity relationships, analogues of the two peptides were designed, resulting in synthesis of frenatin 4.1a (GFLEKLKKGAKDFASALVNSIKGT) and frenatin 4.2a (GFLLKLKLGAKLFASAFVNSIK.NH2). Both analogues exhibited improved antimicrobial activities, especially frenatin 4.2a, which displayed significant enhancement of broad spectrum antimicrobial efficiency. The peptide modifications applied in this study, may provide new ideas for the generation of leads for the design of antimicrobial peptides with therapeutic applications.

Economic Development and Mass Poverty in Africa: Assessment of the Nigerian Experience

The forces surrounding the emerging economies of underdeveloped world, especially Africa has practically stifled its economic progress, growth, development and sustainability. This economic condition brings to the fore the massive onslaught of rural/urban poverty which the African continent grapples with since the post-world war II era to date. The economic misfortunes and incidence of mass poverty in Africa, vis-à-vis Nigeria is used as a point of departure in this study. The paper underscores the ideological and philosophical undertone of international capital manifesting in form of colonialism and imperialism as a major character in the historical process of underdevelopment and mass poverty in peripheral states of Africa, Asia and Latin America, respectively. Of particular interest in this study is the activities of domestic bourgeoisie elite class who have vigorously displayed some degree of lack of much needed vision and abject lack of desires to draw up workable plans to redeem the battered image of African/ Nigerian economic misfortunes. This state of affairs has practically engendered economic underdevelopment, misery and disturbing levels of poverty in the nation-state system. The paper concludes with the forward towards realizing the vision 20-20-20 objectives in the 21t century and beyond.

Air Temperature Distribution and Energy-balance Modelling of a Debris-covered Glacier

Near-surface air temperature is an important determinant of the surface energy balance of glaciers and is often represented by a constant linear temperature gradients (TGs) in models. Spatiotemporal variability in 2 m air temperature was measured across the debris-covered Miage Glacier, Italy, over an 89 d period during the 2014 ablation season using a network of 19 stations. Air temperature was found to be strongly dependent upon elevation for most stations, even under varying meteorological conditions and at different times of day, and its spatial variability was well explained by a locally derived mean linear TG (MG–TG) of −0.0088°C m−1. However, local temperature depressions occurred over areas of very thin or patchy debris cover. The MG–TG, together with other air TGs, extrapolated from both on- and off-glacier sites, were applied in a distributed energy-balance model. Compared with piecewise air temperature extrapolation from all on-glacier stations, modelled ablation, using the MG–TG, increased by <1%, increasing to >4% using the environmental ‘lapse rate’. Ice melt under thick debris was relatively insensitive to air temperature, while the effects of different temperature extrapolation methods were strongest at high elevation sites of thin and patchy debris cover.

An investigation of environmental conditions experienced during the life of high-value wood components and products

Australian forest industries have a long history of export trade of a wide range of products from woodchips (for paper manufacturing), sandalwood (essential oils, carving and incense) to high value musical instruments, flooring and outdoor furniture. For the high value group, fluctuating environmental conditions brought on by changes in temperature and relative humidity, can lead to performance problems due to consequential swelling, shrinkage and/or distortion of the wood elements. A survey determined the types of value-added products exported, including species and dimensions packaging used and export markets. Data loggers were installed with shipments to monitor temperature and relative humidity conditions. These data were converted to timber equilibrium moisture content values to provide an indication of the environment that the wood elements would be acclimatising to. The results of the initial survey indicated that primary high value wood export products included guitars, flooring, decking and outdoor furniture. The destination markets were mainly located in the northern hemisphere, particularly the United States of America, China, Hong Kong, Europe (including the United Kingdom), Japan, Korea and the Middle East. Other regions importing Australian-made wooden articles were south-east Asia, New Zealand and South Africa. Different timber species have differing rates of swelling and shrinkage, so the types of timber were also recorded during the survey. Results from this work determined that the major species were ash-type eucalypts from south-eastern Australia (commonly referred to in the market as Tasmanian oak), jarrah from Western Australia, spotted gum, hoop pine, white cypress, black butt, brush box and Sydney blue gum from Queensland and New South Wales. The environmental conditions data indicated that microclimates in shipping containers can fluctuate extensively during shipping. Conditions at the time of manufacturing were usually between 10 and 12% equilibrium moisture content, however conditions during shipping could range from 5 (very dry) to 20% (very humid). The packaging systems incorporated were reported to be efficient at protecting the wooden articles from damage during transit. The research highlighted the potential risk for wood components to ‘move’ in response to periods of drier or more humid conditions than those at the time of manufacturing, and the importance of engineering a packaging system that can account for the environmental conditions experienced in shipping containers. Examples of potential dimensional changes in wooden components were calculated based on published unit shrinkage data for key species and the climatic data returned from the logging equipment. The information highlighted the importance of good design to account for possible timber movement during shipping. A timber movement calculator was developed to allow designers to input component species, dimensions, site of manufacture and destination, to see validate their product design.

Symbiotic Cities: Buenos Aires, Montevideo, and Mass Culture, 1910-1960

This dissertation examines how Buenos Aires emerged as a creative capital of mass culture and cultural industries in South America during a period when Argentine theater and cinema expanded rapidly, winning over a regional marketplace swelled by transatlantic immigration, urbanization and industrialization. I argue that mass culture across the River Plate developed from a singular dynamic of exchange and competition between Buenos Aires and neighboring Montevideo. The study focuses on the Argentine, Uruguayan, and international performers, playwrights, producers, cultural impresarios, critics, and consumers who collectively built regional cultural industries. The cultural industries in this region blossomed in the interwar period as the advent of new technologies like sound film created profitable opportunities for mass cultural production and new careers for countless theater professionals. Buenos Aires also became a global cultural capital in the wider Hispanic Atlantic world, as its commercial culture served a region composed largely of immigrants and their descendants. From the 1920s through the 1940s, Montevideo maintained a subordinate but symbiotic relationship with Buenos Aires. The two cities shared interlinked cultural marketplaces that attracted performers and directors from the Atlantic world to work in theatre and film productions, especially in times of political upheaval such as the Spanish Civil War and the Perón era in Argentina. As a result of this transnational process, Argentine mass culture became widely consumed throughout South America, competing successfully with Hollywood, European, and other Latin American cinemas and helping transform Buenos Aires into a cosmopolitan metropolis. By examining the relationship between regional and national frames of cultural production, my dissertation contributes to the fields of Latin American studies and urban history while seeking to de-center the United States and Europe from the central framing of transnational history.

An examination of Special Forces and their transfer of skillsets under crisis management settings in Singapore

The thesis focuses on military crisis management and strategy.

Elastic limit: The role of university-focused venture capital firms in extending knowledge and technology transfer

This paper has two main objectives. Firstly, to identify the role of the university-focused intermediaries, specifically UVCs, in order to explain how they interact at the early stage of USO creation, particularly regarding knowledge sharing. Secondly, to analyse whether they change their position once the USO is developed. This gives rise to two Research Questions: How does knowledge sharing occur in the dynamics of a university-based entrepreneurial ecosystem? And Do particular participants, such as UTTOs or UVCs, always occupy the same role and position within the university-based entrepreneurial ecosystem?

Interactions of pyridinium, pyrrolidinium or piperidinium based ionic liquids with water: measurements and COSMO-RS modelling

Looking for a better knowledge concerning water and ionic liquids (ILs) interactions, a systematic study of the activity coefficients of water in pyridinium, pyrrolidinium and piperidinium-based ILs at 298.2 K is here presented based on water activity measurements. Additionally, the study of the structural effects of the pyridinium-based cation is also pursued. The results show that non-aromatic ILs are interacting more with water than aromatic ones, and among the ortho, meta and para isomers of 1-butyl-methylpyridinium chloride, the ortho position confers a more hydrophilic character to that specific IL. The physicalchemistry of the solutions was interpreted based on dissociation constants, natural bond orbitals and excess enthalpies providing a sound basis for the interpretation of the experimental observations. These results show that hydrogen bonding controls the behavior of these systems, being the anion-water one of the most relevant interactions, but modulated by the anionecation interactions.

Impacts of climate change and species distribution modelling: future scenarios to endangered species in South Brazil.

Earth climate has changed significantly in the last century and the different models indicate that it will continue to change over the next decades, even if the emission of greenhouse gases stop immediately. These changes have impact on different plant populations, as well as in the actual distribution of several species. As plants, in general, have a smaller capacity of dispersion compared with the animals it is likely that they will suffer the impacts of the climate change more intensively.