Potential

We deal with the exact solutions of Schrödinger equation characterized by positiondependent effective mass via point canonical transformations. The Morse, Pöschl-Teller and Hulthén type potentials are considered respectively. With the choice of position-dependent mass forms, exactly solvable target potentials are constructed. Their energy of the bound states and corresponding wavefunctions are determined exactly.

Latitudinal shifts in tree species distributions are a potential impact of climate change on forest ecosystems. It has been hypothesized that some tree species may become extirpated as climate change effects may exceed their migration ability. The goal of this study was to compare tree species compositions in northern urban areas to tree compositions in forestland areas in the eastern U.S. as an indicator of the potential for urban trees to facilitate future forest tree species migration. Results indicated that a number of tree species native to eastern U.S. forests of southern latitudes are currently present in northern urban forests. The biomass density (Mg/ha) of urban tree species is typically less than half of forestland densities with the majority of urban tree species found in nearby (<100 km) forestland. Urban tree propagation is often facilitated by humans, whereas the necessary pollinators and agents of tree seed dispersal in forestlands may be lacking regardless of climate change. It is suggested that urban areas may serve divergent, dual roles as both a native tree seed source and refuge for a limited number of forestland tree species, but also a facilitator of non-native tree invasion.

The potential of mesoporous silica-alumina (MSA) modified by acid leaching as alternative support for Pt catalysts was studied in hydrodesulfurization (HDS) of thiophene and benzothiophene. The supports were characterized by N 2 adsorption, XRD, 27 AL MAS NMR, electron microscopy (SEM, HRTEM) and by activities in cyclohexene isomerization and cumene cracking. The composition of the catalysts and Pt dispersion were determined by ICP and H 2 or CO sorption, respectively. Progressive leaching of the parent MSA from 50% Al 2 O 3 to 11% Al 2 O 3 content led to increase of the BET surface area and exposition of strong acidity. This positively affected the activities of the reduced Pt catalysts in thiophene HDS. Deposition of 1.5 wt.% Pt on MSA (11% Al 2 O 3) by using Pt(NH 3) 4 (OH) 2 as precursor gave the best catalyst, several times more active in thiophene HDS than the weight equivalents of sulfided CoMo/Al 2 O 3 or reduced Pt/HY zeolite. In benzothiophene reaction, its activity was slightly above that of CoMo/Al 2 O 3 and about twofold compared to Pt/HY.

We review recent developments in our group regarding the solution-phase synthesis of one-dimensional nanostructures of metals. The synthetic approaches include solution-liquid-solid growth for nanowires of low-melting-point metals such as Pb; seed-directed growth for Ag nanowires, nanobeams, and nanobelts; kinetically controlled growth for Pt nanorods, nanowires, and multipods; and galvanic replacement for nanotubes of Au, Pt, and Pd. Both characterization and mechanistic studies are presented for each nanostructure. Finally, we highlight the electrical and plasmonic properties of these metal nanostructures and discuss their potential applications in nanoscale devices. (1) Xia, Y.; Yang, P.; Sun, Y.; Wu, Y.; Mayers, B.; Gates, B.; Yin, Y.; Kim, F.; Yan, H. Alekseeva, A. V.; Bogatyrev, V. A.; Dykman, L. A.; Khlebtsov, B. N.; Trachuk, L. A.; Melnikov, A. G.; Khlebtsov, N.

Across the world, the distance mode of education is gaining momentum. It is a system in which schools, universities and other educational agencies offer instruction wholly or partly by mail. Eritrea is a newly independent country in Africa and is facing many challenges, particularly in its education sector. It does not have many educational institutions at tertiary level. Thus, distance learning is a valuable option for this country. The distance education program could promote higher education by providing access to large numbers of urban people and disadvantaged groups in rural and remote areas, including working people, fighters, women and other adults. This paper discusses various issues related to the establishment and development of distance education. It presents the distance education programs so far undertaken in the country and explores the potential for distance education in Eritrea.

A new liquefaction potential map of the peninsula of Charleston, South Carolina, is presented in this paper. Liquefaction potential is expressed in terms of the liquefaction potential index (LPI) developed by Iwasaki et al. and calculated using 44 cone penetration test profiles. The cone profiles are supplemented with information from the 1:24,000 scale geologic map by Weems and Lemon, as well as several first-hand accounts of liquefaction and ground deformation that occurred during the 1886 Charleston earthquake. Nearly all of the cases of liquefaction and ground deformation occurred in the Holocene to late Pleistocene beach deposits that flank the higher-ground sediments of the Wando Formation. To match the observed field behavior, an age correction factor of 1.8 is applied to the cyclic resistance ratios calculated for the 100,000-year-old Wando Formation. No age correction is needed for the younger deposits. The map can be a useful tool for planners, engineers, and scientists working to mitigate future earthquake damage in Charleston. 1 Principal Investigator. The original project title of this grant is "Liquefaction P otential Mapping of the Charleston Quadrangle, South Carolina." The support of the USGS is greatly appreciated. The authors also thank the many individuals who assisted with data collection, in particular, William M. Camp and Timothy J. Cleary of S&ME; Thomas J. Casey and William B. Wright of WPC;

A wide class of neutrino physics-motivated models are characterized by the spontaneous violation of a global U(1) lepton number symmetry at or below the electroweak scale by a n SU(2)U(1) singlet vacuum expectation value hi < O (1) TeV. In all these models the main Higgs decay c hannel is likely to be "invisible", e.g. h ! JJ, where J denotes the associated weakly interacting pseudoscalar Goldstone bosonthe majoron. This leads to events with large missing energy that could be observable at LEP and aect the Higgs mass bounds obtained, as well as lead to novel ways to search for Higgs bosons at high energy supercolliders such as the LHC/SSC.

Nepal, a country rich in biomass, still does not have any commercial pellet production plants and is wasting large amounts of agricultural crop residue. The current study showed that about 5.61 million tonnes (Mt) of biomass in the form of pellets are potentially available from agricultural crop residues. The brick and cement industries could use these agro-pellets. Co-firing of pellets in such industries could play an important role in reducing the import volume of coal and minimize the related environmental loadings.

If P is a differential operator with constant coefficients, an identity is derived to calculate the action of e P on the product of two functions. In many-body theory, P describes the interaction Hamiltonian and the identity yields a hierarchy of Green functions. The identity is first derived for scalar fields and the standard hierarchy is recovered. Then the case of fermions is considered and the identity is used to calculate the generating function for the Green functions of an electron system in a time-dependent external potential.

Hybrid plasma catalyst technology has great potential for indoor air purification. However, humidity is a critical parameter in plasma catalytic processes. In this work, several catalysts were tested downstream of a DC corona discharge and the effect of humidity was investigated on both ozone and toluene removal. Next, sorption measurements onto the catalysts were performed for toluene, trichloroethylene and acetone, using an equilibrium partitioning in closed system procedure to explain the obtained results in a quantitative manner.

Nigeria's electricity demand increases due to growth in industrialization and socioeconomic weight. Regrettably, power industry of the country has not been able to satisfy the need of their customers. Therefore, if the country is to meet its energy demand alternative sources of power generation are very essential. Opportunities abound in hydropower scheme development as a viable energy source of electricity which will curtail and minimize greenhouse gases and emissions into environment. Meanwhile, there are small rivers all over the country with potential sites suitable for small hydropower scheme, development of which will ensure the supply of electricity to remote communities. This can be used as a substitute for commercial fuels, which effect reduce cost of fuelling and raise the earning potential of the rural communities.

Aluminum doped zinc oxide (AZO) nanometric particles were synthesized by hydrothermal method. Aluminum nitrate hydrate, aluminum sec-butoxide and zinc nitrate hydrate were used as the starting materials, and n-propanol and 2-butanol were used as solvents. Ratio of Al2O3 in ZnO was kept at 10 wt%. Reaction was conducted in a Teflon autoclave at 175–225 °C for 5 h. Ratios of alcohol, H2O and HCl to zinc nitrate hydrate were altered and 6 different sets of parameters were investigated. Obtained products were subjected to powder-XRD, particle size measurement, TEM examination and AAS analysis. Single phase AZO particles were obtained at alcohol to zinc nitrate ratio of 35, acid to zinc nitrate ratio of 0.2, at 225 °C. Particle size was determined as 3.2 ± 0.4 nm from TEM examinations and as 1–2 nm from dynamic light scattering. Synthesized particles have amphiphilic character, thus they can be dispersed in both polar and non-polar media. It was seen from the UV-diffuse reflectance spectra that the AZO powder had low reflectance in the UV region and high reflectance in the visible region. The obtained powder has the potential to be utilized in the form of thin films for optical and electronic purposes.

This article deals with the investigation of the mechanisms for the activation of businesses in the Ukraine. It is possible through increasing the cooperation with the European Union (EU). The paper emphasizes the need for radical changes in the conduct of Ukrainian businesses in order to enhance investment and innovation. This paper proposes that today the international integration processes in the Ukraine require new approaches and technology cooperation, promotion the transfer of innovation, and the investment processes. Indicated in this paper are the current approaches and new challenges that have arisen today which require rapid reorientation of the close relationship of science and industry and the development of information and in the infrastructure sector. The authors propose the use the cluster integration processes in the region for intensification investment and innovation activity that is necessary today to strengthen cooperation with the EU. The paper is presents a met...

Every year millions of tons of agricultural wastes are generated which are either destroyed or burnt inefficiently in loose form causing air pollution. These wastes can be recycled & can provide a renewable source of energy by converting biomass waste into different form of energy sources. This recycled fuel is beneficial for the environment as it conserves natural resources. For this the biomass is the main renewable energy resource.

I offer an overview of the rapidly growing field of mindfulness-based interventions (MBIs). A working definition of mindfulness in this context includes the brahma viharas, sampajanna and appamada, and suggests a very particular mental state which is both wholesome and capable of clear and penetrating insight into the nature of reality. The practices in mindfulness-based stress reduction (MBSR) that apply mindfulness to the four foundations are outlined, along with a brief history of the program and the original intentions of the founder, Jon Kabat-Zinn. The growth and scope of these interventions are detailed with demographics provided by the Center for Mindfulness, an overview of salient research studies and a listing of the varied MBIs that have grown out of MBSR. The question of ethics is explored, and other challenges are raised including teacher qualification and clarifying the "outer limits," or minimum requirements, of what constitutes an MBI. Current trends are explored, including the increasing number of cohort-specific interventions as well as the publication of books, articles, and workbooks by a new generation of MBI teachers. Together, they form an emerging picture of MBIs as their own new "lineage," which look to MBSR as their inspiration and original source. The potential to bring benefit to new fields, such as government and the military, represent exciting opportunities for MBIs, along with the real potential to transform health care. Sufficient experience in the delivery of MBIs has been garnered to offer the greater contemplative community valuable resources such as secular language, best practices, and extensive research.

This paper describes how data from a variety of sources are merged to present new countrywide maps of the solar energy distribution over Ethiopia. The spatial coverage of stations with radiation data was found to be unsatisfactory for the purpose of a countrywide solar energy assessment exercise. Therefore, radiation had to be predicted from sunshine hours by employing empirical models. Using data from seven stations in Ethiopia, linear and quadratic correlation relationships between monthly mean daily solar radiation and sunshine hours per day have been developed. These regional models show a distinct improvement over previously employed countrywide models. To produce a national solar-energy distribution profile, a spatial extension of the radiation/sunshine relationships had to be carried out. To do this, the intercepts (a) and slopes (b) of each of the seven linear regression equations and another six from previous studies, completed in neighbouring Sudan, Kenya and Yemen, were used to interpolate the corresponding values to areas between them. Subsequent to these procedures, 142 stations providing only sunshine data were assigned their "appropriate" a and b values to estimate the amount of solar radiation received, which was then used to produce annual and monthly solar radiation distribution maps for Ethiopia. The results show that in all regions solar energy is an abundant resource.

Moving walkways have been used for people transport for more than a century. One of the latest innovations in this field is the Accelerating Moving Walkway (AMW), which provides higher transport speed. However, the application of moving walkways is still limited to short-distance travel up to 300 m. This paper summarizes and analyses the findings of a literature review on (accelerating) moving walkways, which aims to compare the characteristics of AMWs with other public transport systems, namely buses, light rails, Automated People Movers (APMs), and Personal Rapid Transits (PRTs). Based on the comparative evaluation, we conclude that AMWs can be competitive to the other transport modes. Hence, we propose the potential application of AMWs for the transport of people, i.e. pedestrians, over longer distances. Subsequently, issues related to the concept of long-distance AMWs are briefly introduced as topics for further research.

The conversion of CO 2 with H 2 to methanol (MeOH) over a commercial Cu/ZnO catalyst (Süd-Chemie, Germany) was studied under process conditions. The obtained results showed a good stability of the catalytic system and a large potential for a CO 2 emission reduction with simultaneous production of MeOH or dimethyl ether (DME) as bulk chemicals or alternative fuels. If H 2 is obtained from renewable or CO 2neutral sources (e.g. biomass, solar, wind or nuclear energy), respectively, a potentially CO 2 -neutral cycle is possible. Compared to the conventional synthesis gas based technologies like the Lurgi MegaMethanol ® process, the CO 2 -based process shows lower productivities. However, since the overall reaction is less exothermic, lower temperature peaks and lower byproduct contents are found at similar process conditions. The higher purity is beneficial for further chemical conversions, like the DME synthesis. In the Lurgi MegaDME ® technology, DME is produced efficiently in terms of costs and energy demand and can be used as alternative fuel for diesel engines. The MegaDME technology, based on the Lurgi MegaMethanol ® process, allows overall capacities of up to 1.5 Mio t a −1 DME in a single process train from syngas generation via Methanol synthesis, to DME synthesis and product purification without parallelized equipment.

In the face of seemingly intractable territorial and maritime disputes in the South China Sea, the article examines how the 1982 United Nations Convention on the Law of the Sea (LOSC), sets out what maritime claims States can make in the South China Sea and how it establishes a framework that will enable States to either negotiate maritime boundary agreements or negotiate joint development arrangements ( JDAs) in areas of overlapping maritime claims. It provides an avenue whereby the maritime claims of the claimants can be brought into line with international law, potentially allowing for meaningful discussions on cooperation and maritime joint development based on areas of overlapping maritime claims defined on the basis of the LOSC.

Common bean production in Africa suffers from different constrains. The main damage is caused by insect pest infestations in the field. The most common insects pests which attack common bean in the field are the bean stem maggot (Ophiomyia phaseoli), ootheca (Ootheca bennigseni) and aphids (Aphis fabae). Currently, few farmers in Africa are using commercial pesticides for the control of these insect pests. Due to the negative side effects of commercial pesticides to human health and the environment, there is a need for developing and recommending alternative methods such as those involving agronomic and botanical/biological measures in controlling common bean insect pests. This review aim to report the most common insects pests which attack common bean (Phaseolus vulgaris L.) in the field and explore the potential of agronomic, biological and botanical methods as a low-cost, safe and environmentally friendly means of controlling insect pests in legumes.

Please cite this article in press as: McDermott MS, While AE. Maximizing the healthcare environment: A systematic review exploring the potential of computer technology to promote self-management of chronic illness in healthcare settings. Patient Educ Couns (2013), http://dx.Please cite this article in press as: McDermott MS, While AE. Maximizing the healthcare environment: A systematic review exploring the potential of computer technology to promote self-management of chronic illness in healthcare settings. Patient Educ Couns (2013), http://dx.Please cite this article in press as: McDermott MS, While AE. Maximizing the healthcare environment: A systematic review exploring the potential of computer technology to promote self-management of chronic illness in healthcare settings. Patient Educ Couns (2013), http://dx.

Membrane contactors based on microporous hydrophobic materials already offer remarkable performances for different separation applications at industrial scale, especially for gas-liquid mass transfer operations. Impressive process intensification effects can indeed be achieved in certain cases, due to the large interfacial area provided by hollow fiber membranes. Nevertheless, depending on the membrane and fluid properties, great differences in mass transfer can be obtained; undesirable effects due to liquid contact such as gradual changes in membrane structure and/or partial wetting of the pores can dramatically affect mass transfer performances. Numerous studies have addressed these difficulties for one of the most attracting and challenging application of membrane contactors: the absorption of CO 2 in a chemical solvent in order to achieve post-combustion CO 2 capture from flue gases. For this application, given the fast chemical reaction which takes place in the liquid phase, a highly permeable membrane material is absolutely necessary. Additionally, the membrane material has to withstand long term contact with a chemically reactive solvent (typically an amine such as monoethanolamine: MEA) and has to remain non wetted. A possible solution which prevents wetting problems together with a minimal impact on the membrane mass transfer coefficient is reported in this study; the key idea is to make use of a composite membrane based on a thin dense skin, based on a highly permeable glassy polymer, coated on a microporous support. In a first step, screening tests have been performed in order to identify potential polymer candidates for the thin skin, combining a high CO 2 permeability and solvent (MEA) compatibility on long time scales. In a second step, composite hollow fibers with a thin skin (Teflon AF ® , PTMSP) coated on a porous support (PP) have been prepared and tested. The concept has been finally tested and validated at lab scale for CO 2 capture from a gas mixture into aqueous solutions of MEA with hollow fiber modules. Remarkably, the overall mass transfer performances of the composite fibers compete with the most permeable microporous membranes classically proposed for membrane contactor applications. The possible use of these novel composite fibers for other applications and the extension of the concept to different industrial situations are discussed.

In this communication biomass energy resource, potential, energy conversion and policy for promotion implemented by Government of India are discussed. The total installed capacity for electricity generation in India is 2666.64 GW as on 31st March 2013. Renewable energy is contributed 10.5% of total generation out of which 12.83% power is being generated using biomass. India has surplus agricultural and forest area which comprises about 500 million metric tons of biomass availability per year. In India total biomass power generation capacity is 17,500 MW. At present power being generated is 2665 MW which include 1666 MW by cogeneration. The various category of biomass in India is also discussed in this paper. And the research reveals that India has large potential for bio mass feed stock from different sources. Government of India deployed different policies and executed that the strategies for biomass power generation. Such approaches have included the whole biomass energy sector which incorporated the bio gas, bio diesel etc. in the policies. Government of India has focused on the deployment and development biomass energy sector with strategic policy and program which is notable portion of this review paper.

Agroecosystems have a critical role in the terrestrial carbon cycling process. Soil organic carbon (SOC) in cropland is of great importance for mitigating atmospheric carbon dioxide increases and for global food security. With an understanding of soil carbon saturation, we analyzed the datasets from 95 global long-term agricultural experiments distributed across a vast area spanning wide ranges of temperate, subtropical and tropical climates. We then developed a statistical model for estimating SOC sequestration potential in cropland. The model is driven by air temperature, precipitation, soil clay content and pH, and explains 58% of the variation in the observed soil carbon saturation (n=76). Model validation using independent data observed in China yielded a correlation coefficient R 2 of 0.74 (n=19, P<0.001). Model sensitivity analysis suggested that soils with high clay content and low pH in the cold, humid regions possess a larger carbon sequestration potential than other soils. As a case study, we estimated the SOC sequestration potential by applying the model in Henan Province. Model estimations suggested that carbon (C) density at the saturation state would reach an average of 32 t C ha −1 in the top 0-20 cm soil depth. Using SOC density in the 1990s as a reference, cropland soils in Henan Province are expected to sequester an additional 100 Tg C in the future.

A study of the dissolution of several copper concentrates under controlled potential conditions in chloride solutions has demonstrated that the rate of dissolution of chalcopyrite is strongly dependent on the potential of the solution. Linear rates were obtained for the dissolution of chalcopyrite in solutions containing 0.2 M HCl and 0.5 g L − 1 Cu(II) at 35°C. The rate is enhanced within a range of potentials of 550 to 620 mV (versus SHE) and the presence of dissolved oxygen is essential for enhanced rates within this potential window. Even though dissolved oxygen is important in order to achieve acceptable rates of dissolution, excessive oxidation can increase the potential into a region in which passivation is possible. Reduction of the potential into the optimum region results in restoration of enhanced rates of dissolution. On the other hand, dissolution at low potentials (b 540 mV) results in reduced rates of copper dissolution which increase significantly when the potential is subsequently increased to above 580 mV. Mineralogical studies have shown that chalcopyrite remains un-leached and small amounts of covellite appear to be formed on the surface of the chalcopyrite at low potentials. All concentrates appear to dissolve at roughly the same rate under the same conditions, despite differences in the composition and mineralogy of the samples.

This paper describes how data from a variety of sources are merged to present new countrywide maps of the solar energy distribution over Ethiopia. The spatial coverage of stations with radiation data was found to be unsatisfactory for the purpose of a countrywide solar energy assessment exercise. Therefore, radiation had to be predicted from sunshine hours by employing empirical models. Using data from seven stations in Ethiopia, linear and quadratic correlation relationships between monthly mean daily solar radiation and sunshine hours per day have been developed. These regional models show a distinct improvement over previously employed countrywide models. To produce a national solar-energy distribution profile, a spatial extension of the radiation/sunshine relationships had to be carried out. To do this, the intercepts (a) and slopes (b) of each of the seven linear regression equations and another six from previous studies, completed in neighbouring Sudan, Kenya and Yemen, were used to interpolate the corresponding values to areas between them. Subsequent to these procedures, 142 stations providing only sunshine data were assigned their "appropriate" a and b values to estimate the amount of solar radiation received, which was then used to produce annual and monthly solar radiation distribution maps for Ethiopia. The results show that in all regions solar energy is an abundant resource.

Separation of carbon dioxide (CO 2 ) from gaseous mixture is an important issue for the removal of CO 2 in natural gas processing and power plants. The ordered mesoporous silicas (OMS) with uniform pore structure and high density of silanol groups, have attracted the interest of researchers for separation of carbon dioxide (CO 2 ) using adsorption process. These mesoporous silicas after functionalization with amino groups have been studied for the removal of CO 2 . The potential of functionalized ordered mesoporous silica membrane for separation of CO 2 is also recognized. The present paper reviews the synthesis of mesoporous silicas and important issues related to the development of mesoporous silicas. Recent studies on the CO 2 separation using ordered mesoporous silicas (OMS) as adsorbent and membrane are highlighted. The future prospectives of mesoporous silica membrane for CO 2 adsorption and separation are also presented and discussed.

The corrosion of reinforcing steels in concrete is the main reason for the deterioration of bridge decks. An accurate method for measuring corrosion is a fundamental prerequisite for the detection of damaged areas and for planning an effective method for repairing bridge decks. A laboratory study was conducted to estimate the corrosion activity of a reinforcing steel embedded in two types of concrete, ordinary and highperformance, using different corrosion measurement methods. Results indicated that Tafel plot (TP), linear polarization resistance, half-cell potential (HCP), and chloride content methods would assess the same level of corrosion activity in only 24% of specimens. D

An overview is presented of some cosmological aspects of string theory. Recent developments are emphasised, especially the attempts to derive inflation or alternatives to inflation from the dynamics of branes in string theory. Time dependent backgrounds with potential cosmological implications, such as those provided by negative tension branes and S-branes and the rolling string tachyon are also discussed. † * Permanent address.

Apple co-founder, Woznaik states that " blockchain is the next major IT revolution that is about to happen ". Blockchain has the potential to disrupt the existing reforms of any sector in the economy. Appreciating the potential the blockchain has to cause revolutionary changes in the economy a research is conducted to study the major issues relating to the blockchain. The research is divided into three parts. The first part describes the procedure followed for development of a private blockchain step-wise; Deployment of blockchain developed to the housing sector on a simulation basis is dealt in the second part while the unique benefits of blockchain deployment with particular reference to housing sector are underscored in the third part. The second and third part of the research is presented in the current research paper.

This research investigated the potential utilization of solid waste from palm oil industry for liquid smoke production in Aceh Province, Indonesia. The liquid smoke can be applied as bio fungicides in agricultural field. Preliminary experiment on the use of liquid smoke as fungicide at Colletotrichum capsisi fungus which causes anthracnose disease on red pepper was also conducted. The survey on the existing potential/availability of palm oil mill in Aceh shows that there are 30 palm oil mills in eight districts with a total of production capacity 1020 ton/hour. Assuming that 10% of palm oil kernel shells are pyrolized into liquid smoke, Aceh province could produce about 23,868 ton of liquid smoke per year. The preliminary test result towards Colletotrichum capsisi fungus shows that the liquid smoke can be used as fungicides.

This paper examines trends, potential and challenges in online learning. We consider 6 online learning trends and the issues associated with the trends. These include a one sided emphasis on the technology; physical versus online presences; formal face-to-face versus distance/workplace education; mono-versus multilingual online learning; open source versus proprietary software; and the open standard oxymoron. The potential of online learning include 4 factors of accessibility, flexibility, interactivity, and collaboration of online learning afforded by the technology. In terms of the challenges to online learning, 6 are identified: defining online learning; proposing a new legacy of epistemology-social constructivism for all; quality assurance and standards; commitment versus innovation; copyright and intellectual property; and personal learning in social constructivism. The authors contend the necessity of developing new ways of thinking to face the challenges relating to the development of online learning.

An overview is presented of some cosmological aspects of string theory. Recent developments are emphasised, especially the attempts to derive inflation or alternatives to inflation from the dynamics of branes in string theory. Time dependent backgrounds with potential cosmological implications, such as those provided by negative tension branes and S-branes and the rolling string tachyon are also discussed. † * Permanent address.

Smallholder irrigation in Central Mozambique predominantly takes place in an informal setting. This renders these smallholders and their activities invisible for policy purposes. Identification efforts of smallholder irrigation as well as the potential for new irrigation development are often the basis for policy setting. But the potential is often approached technocratically: the technical availability of water and land with the assumption that smallholder irrigation is not happening and should be developed. Although more and more effort is done to include social economical aspects into the identification as well, it remains a GIS exercise, based on incomplete data using large pixel sizes, analyzing countries or continents as a whole. This study describes and presents the methodology and the results of an irrigation potential identification exercise carried out in two studies in Central Mozambique. Apart from describing the identification methods used, this study highlights the extent of farmer-led irrigation development, its drivers and the potential for farmer-led smallholder irrigation development. This study demonstrates the prolific nature of smallholder irrigation, arguing for the recognition that smallholder farmers are already developing irrigation and that this should lead to changing the focus of identification efforts towards the drivers behind farmer-led irrigation development. Using these context-specific drivers to define the potential for new irrigation development should result in a better response in policy to both the technical and socio-economical potential of smallholder irrigation development.