Resource Limitation

In a world faced with accelerating climate change, economic instability and resource limits, it is urgent to find better indicators of progress towards sustainability. The available indicators mostly succeed at measuring unsustainable trends that can be targeted by management action, but fall short of defining or ensuring sustainability. A recent review of environmental assessment and reporting at the national level for the United Nations Environment Programme shows about half of reporting countries to be using indicators and provides some lessons learned. However indicators at the national level are not sufficient. The challenges ahead include finding indicators of change in dynamic systems, establishing sustainability targets towards which national progress can be measured, developing global level indicators of planetary sustainability, and providing individuals with indicators reflecting their own progress and providing positive incentives for further efforts. Finally, since achieving sustainability is fundamentally an ethical challenge, a new set of values-based indicators is required to measure and motivate the implementation of ethical principles necessary to guide the transition towards sustainability.

Power law cumulative frequency (P) vs. event size (l) distributions P (≥ l) ∼ l −α are frequently cited as evidence for complexity and serve as a starting point for linking theoretical models and mechanisms with observed data. Systems exhibiting this behavior present fundamental mathematical challenges in probability and statistics. The broad span of length and time scales associated with heavy tailed processes often require special sensitivity to distinctions between discrete and continuous phenomena. A discrete Highly Optimized Tolerance (HOT) model, referred to as the Probability, Loss, Resource (PLR) model, gives the exponent α = 1/d as a function of the dimension d of the underlying substrate in the sparse resource regime. This agrees well with data for wildfires, web file sizes, and electric power outages. However, another HOT model, based on a continuous (dense) distribution of resources, predicts α = 1 + 1/d. In this paper we describe and analyze a third model, the cuts model, which exhibits both behaviors but in different regimes. We use the cuts model to show all three models agree in the dense resource limit. In the sparse resource regime, the continuum model breaks down, but in this case, the cuts and PLR models are described by the same exponent.

Rhamnus alaternus L. is a dioecious, fleshy-fruited shrub, typical of Mediterranean vegetation, which has been recorded from the region since the tropical Tertiary. Reproductive biology of this species has been studied in Southern Italy over a period of 4 years with both field and laboratory experiments. In all the studied populations male plants predominate over the females, have a higher flower density and flower regularly every year while females are usually alternate-bearing. A strong negative association between fruit formation and vegetative growth has been found indicating that the presence of fruits on a branch reduces the growth of new shoots. This phenomenon, together with alternate-bearing, is evidence of a strong competition between vegetative growth and reproductive activity and indicates resource limitation. Flower morphology and quantity of pollen produced are typical of insect pollinated species, and flies of the Empididae and Muscidae were trapped bearing pollen at female plants but pollen is also dispersed by wind. Field experiments on pollination success showed that the exclusion of insects as pollen vectors produces a significant decrease in fruit development. Excess pollen provided by hand-pollination increases fruit set over open-pollination and reproductive success in the field is therefore pollen limited. The variability of sex expression, male fitness, fruit production, regrowth and pollination presented here suggests that these predispersal characteristics of R. alaternus have been subject to evolutionary change since the tropical Tertiary climate was replaced by a Mediterranean one. This points to the possibility that reproductive, as well as morphological and physiological characteristics, may be equally selected for in extreme environments such as the Mediterranean.

This research describes the formalization of statements of the form fact f is irrelevant to fact g given theory M. We motivate the need for representing and reasoning with such statements in problem-solving systems, and outline the semantics and properties of statements about ...

Purpose: This communication reports skeletal pathology in a Pleistocene endemic deer from the Mavromouri caves of Crete. Materials: 287 bones and bone fragments from Mavromouri caves are compared to 2986 bones from Liko Cave. Methods: Bones were evaluated macroscopically, and measurements were made of morphometric characteristics of limb long bones. Representative bone specimens were examined radiographically and histologically. Results: Macroscopic hallmarks were loss of bone mass and increased porosity. The long bones were brittle, some of them having thin cortices, and others reduction of medullary cavities that contain dense Haversian tissue. The flat bones were spongy and fragile. Erosions of the metaphyses and articular surfaces were noted. Histological findings included: sub-periosteal resorption; loss of lamellar bone; enlargement of vascular canals; and re-modeling of cortical bone. Two types of fibrous osteodystrophy were recognized in skeletal remains, subostotic and hyperostotic. Conclusions: The deer of Mavromouri caves were affected by severe metabolic bone disease, likely nutritional secondary hyperparathyroidism. We hypothesize a multifactorial cause, including overgrazing, flora senescence, soil mineral deficiencies, and a prolonged period of climate extremes, degrading the Cretan deer habitat. Value: This is the first evidence of a metabolic bone disease causing this level of destructive pathology in an insular fossil deer. Limitations: The lack of absolute chronometric dates for the site limits potential linking with the prevailing environmental conditions. Suggestions for further research: Investigation of similar skeletal pathologies at other islands or isolated habitats is advised.

resulting in a pass rate of 51%. Scores ranged from 34.8% to 70.5%. Overall, 80% of students considered the OSCE to be a more objective clinical assessment tool, most appreciated the time-efficiency of the process, and all respondents were in favour of adopting the OSCE as a permanent tool. Future plans in the Department of Internal Medicine include the adoption of the OSCE in Years 4 and 6. In addition, the Departments of Psychiatry and Preventive Dentistry are investigating possible uses of the OSCE model.

Trade-offs between acquisition capacities for aboveground and belowground resources were investigated by studying the phenotypic plasticity of leaf and root traits in response to different irradiance levels at low nutrient supply. Two congeneric grasses with contrasting light requirements, Dactylis glomerata and D. polygama, were used. The aim was to analyze phenotypic covariation in components of leaf area and root length in response to above-and belowground resource limitation and the consequences of this variation for resource acquisition and plant growth. At intermediate shading (30 and 20% of full sunlight) the plants were able to maintain their total root length, despite a strongly increased total leaf area and a reduced biomass allocation to roots. This was associated with an unaltered or slightly increased nutrient uptake and growth. At 5.5% relative irradiance, growth was severely reduced, especially in the shade-tolerant D. polygama. The results show that constraints on acquisition capacities for aboveground and belowground resources, caused by biomass allocation, may be alleviated by plasticity in other traits such as tissue-mass density and thickness of roots and leaves. The results also suggest different adaptive constraints for phenotypic plasticity and for genetically determined interspecific variation. Phenotypic plasticity tends to maximize resource acquisition and growth rate in the short term, whereas the higher tissue-mass density and the longer leaf life-span of shade-tolerant species indicate reduced loss rates as a more advantageous speciesspecific adaptation to shade in the long term.

Background Radiological imaging is paramount for defining the genitourinary fistulae commonly associated with anorectal malformations prior to definitive surgery. The imaging options are resource-limited in many parts of the world. Nonfluoroscopic pressure colostography after colostomy is a cheap method for the evaluation of anorectal malformations. Objective To describe our experience with nonfluoroscopic pressure colostography in the evaluation of anorectal malformations in boys. Materials and methods The study included 12 boys with anorectal malformation who had colostomy and nonfluoroscopic pressure-augmented colostography with water-soluble contrast medium between January 2006 and December 2007. Results Patient ages ranged from 2 days to 1 year. The types of genitourinary fistula were rectovesical (7.7%) and rectourethral (92.3%). Oblique radiographs were of diagnostic value in all patients. The types of anorectal malformations were high, intermediate and low in 75%, 8.3% and 16.7%, respectively. Short-segment urethral constriction was a common feature of rectourethral fistula (75%, n=9). Conclusion Our experience has shown that genitourinary fistulae associated with anorectal malformations can be demon-strated reliably by nonfluoroscopic pressure colostography with two oblique radiographs, providing an option in resource-poor settings where fluoroscopic equipment is scarce.

Although weed research in maize has broadened from an emphasis on herbicide technology to include studies of weed± maize competition, many studies only consider competition descriptively (e.g. de®ning the critical period for weed control). Furthermore, studies of the mechanisms of weed competition in maize have considered only competition for resources such as soil moisture, nutrients and light. Physiological ecologists have recently recognized the signi®cance of early detection of neighbouring plants through the far-red/red (FR/R) signal as an important mechanism affecting plant±plant interactions. In this review, we have indicated the importance of integrating the concept of the mechanism of early detection of neighbours with the resource-limiting approach in reassessing weed competition in maize during the critical time for weed control. Hypothetical integration of early detection of neighbours into the existing concepts of critical time for weed control and weed thresholds led us to view maize±weed competition as a series of complex processes, which is triggered by the FR/R signal and followed by the development of shade avoidance characteristics accompanied by a reduction in the plant's ability to absorb nutrients and water, and to photosynthesize. However, due to lack of research on effects of weeds on light quality impinging corn plants as well as corn response to an increase in FR light during critical time for weed control, our conclusions remain to be speculative. We believe that incorporation of early detection of neighbours through the FR/R ratio as a primary signal during the critical period for weed control would open a new approach for future studies on weed competition in maize. We recognize that resource limitation occurs in a maize±weed association, however, this may be more of an effect rather than a cause of competition.

Cassava or manioc (Manihot esculenta Crantz), a perennial shrub of the New World, currently is the sixth world food crop for more than 500 million people in tropical and sub-tropical Africa, Asia and Latin America. It is cultivated mainly by resource-limited small farmers for its starchy roots, which are used as human food either fresh when low in cyanogens or in many processed forms and products, mostly starch, flour, and for animal feed. Because of its inherent tolerance to stressful environments, where other food crops would fail, it is often considered a food-security source against famine, requiring minimal care. Under optimal environmental conditions, it compares favorably in production of energy with most other major staple food crops due to its high yield potential. Recent research at the Centro Internacional de Agricultura Tropical (CIAT) in Colombia has demonstrated the ability of cassava to assimilate carbon at very high rates under high levels of humidity, temperature and solar radiation, which correlates with productivity across all environments whether dry or humid. When grown on very poor soils under prolonged drought for more than 6 months, the crop reduce both its leaf canopy and transpiration water loss, but its attached leaves remain photosynthetically active, though at greatly reduced rates. The main physiological mechanism underlying such a remarkable tolerance to drought was rapid stomatal closure under both atmospheric and edaphic water stress, protecting the leaf against dehydration while the plant depletes available soil water slowly during long dry periods. This drought tolerance mechanism leads to high crop water use efficiency values. Although the cassava fine root system is sparse, compared to other crops, it can penetrate below 2 m soil, thus enabling the crop to exploit deep water if available. Leaves of cassava and wild Manihot possess elevated activities of the C4 enzyme PEP carboxylase but lack the leaf Kranz anatomy typical of C4 species, pointing to the need for further research on cultivated and wild Manihot to further improve its photosynthetic potential and yield, particularly under stressful environments. Moreover, a wide range in values of K m (CO2) for the C3 photosynthetic enzyme Rubisco was found among cassava cultivars indicating the possibility of selection for higher affinity to CO2, and consequently higher leaf photosynthesis. Several plant traits that may be of value in crop breeding and improvement have been identified, such as an extensive fine root system, long leaf life, strong root sink and high leaf photosynthesis. Selection of parental materials for tolerance to drought and infertile soils under representative field conditions have resulted in developing improved cultivars that have high yields in favorable environments while producing reasonable and stable yields under stress.

P < 0.05). Surprisingly, few micronutrient deficiencies were found, except for low serum levels of vitamin A (44% of patients). Conclusion. Acute malnutrition, superimposed on chronic malnutrition, is common in patients with Wilms tumour in Malawi. Earlier presentation needs to be encouraged. Chiponde, a peanut butter based ready-to-use-therapeutic-food, is an attractive means of nutritional support which needs further study.

Wireless Sensor Network (WSN) is an emerging technology that shows great assure for various futuristic applications both for public and military. Many researchers tried to develop further cost and energy efficient computing devices and algorithms for WSN but the most challenging is to fit the security of WSN into that strained environment. However, security is crucial to the success of applying WSN. So it becomes essential to be familiar with the security aspects of WSN before designing WSN system. When sensor networks are deployed in an aggressive terrain, security becomes extremely important, as they are prone to different types of despite attacks. The intent of this paper is to investigate security problems and various security requirements. We identify the attacks at all the layers of WSN network architecture and also tried to find their possible solution.

Introduction: Identification of yeast isolated from clinical specimens to the species level has become increasingly important. Ever-increasing numbers of immuno-suppressed patients, a widening range of recognized pathogens, and the discovery of resistance to antifungal drugs are contributing factors to this necessity. Material and methods: A total of 487 yeast strains were studied for the primary isolation and presumptive identification, directly from clinical specimen. Efficacy of CHROMagar Candida has been evaluated with conventional methods including morphology on Corn mealÁtween 80 agar and biochemical methods by using API 20 C AUX.

The extant population of Hawaiian monk seal (Monachus schauinslandi) numbers around 1,00 distributed among six island atolls in the remote Northwestern Hawaiian Islands (NWHI) and at several small, emerging colonies on the Main Hawaiian Islands. Demographic studies have identified poor juvenile survival as the ultimate primary cause of substantial declines at all colonies and of slow recent recovery at some. Variable foraging success may be a key proximate effect, but the knowledge of habitat needs of foraging monk seals has not been adequate to test that hypothesis nor to provide management with the necessary information to address resource conservation issues. We documented the geographic and vertical foraging patterns of 1 Hawaiian monk seals from all six NWHI breeding colonies from 1 through 00 to describe the marine habitats that may be key to the species' viability. We found that seals foraged extensively within barrier reefs of the atolls and on the leeward slopes of reefs and islands at all colony sites. They also ranged away from these sites along the Hawaiian Islands Archipelago submarine ridge to most nearby seamounts and submerged reefs and banks. Most dives were less than 10 m deep, though dives of some seals exceeded 0 m. Suitable foraging habitat may be a resource limiting the population of monk seals in the NWHI. Moreover, the foraging biogeography of Hawaiian monk seals may vary spatially and temporally with variation in the extent of physical substrate, prey community composition and species' abundance, and demographic composition of seal colonies. _________________________________________________

Areas permanently cultivated under DMC systems (Direct seeding mulch-based cropping systems, which are part of the family of practices known as Conservation Agriculture) have increased remarkably in Latin America over recent decades, reaching around 50% of total cropped area in Brazil, Paraguay and Argentina. These systems have been developed to counteract soil degradation and to achieve more sustainable grain production. Under tropical and subtropical conditions the efficiency of such systems increases with the introduction of multi-functional cover crops growing in rotation with the main commercial crops or whenever climatic conditions are too risky for planting a commercial crop. The introduction of cover crops leads to a better utilization of available natural resources throughout the year, more biomass production, permanent soil protection and higher organic restitutions to the soil. DMC systems also offer environmental, economic and agronomic advantages to farmers. Nevertheless they are quite complex systems and their adaptation to specific local constraints and conditions is not straightforward, especially in the case of smallholder, resource-limited agriculture. Specific approaches have been designed, based on systemic and participatory research principles, to create, adapt and disseminate these systems among farmers by working mainly under actual farming conditions. The active participation of farmers and their organizations is fundamental at all stages, as well as that of other key stakeholders of the agricultural sector. Farmers, researchers and their key partners still need to meet several challenges to further increase the success and large-scale adoptability of DMC systems. These include understanding and enhancing the underlying biological processes, creating DMC systems less dependant on chemicals or external inputs, as well as fitting these systems for conditions of close interactions between agriculture and livestock production. These last two challenges are especially true for small-scale farmers operating in marginal environments. Also, the knowledge and experience about DMC systems functioning, creation and management, and about adoption stories, needs to be better systematized and made available through the development of synthetic tools such as data bases, dynamic models and global indicators of DMC system functioning and impact, as well as through enhanced networking among the different stakeholders. Putting together these various pieces will facilitate the conception and implementation of new projects aiming to enhance DMC adaptation and adoption. Media summary Direct seeding mulch-based cropping (DMC) systems are currently adopted on large areas of Latin America to obtain a sustainable production of grain, increasing agronomic, economic and environmental efficiency.

Advances in material growth techniques have recently made large volume LaBr 3 :Ce crystals commercially available. These scintillators are currently being assessed by ESA for use as remote sensing gamma-ray spectrometers on future planetary missions. In addition to their superior scintillation properties (high light output, fast time response and good stopping power), they offer significant benefits when designing gamma-ray detection systems for resource-limited spacecraft-not only in terms of resources but also in terms of reliability and robustness. We present the results of an investigation into the gamma-ray detection properties of a 2 00 Â 2 00 LaBr 3 :Ce crystal, characterized using radioactive sources over the energy range 14-3220 keV. The response of the crystal was found to be largely linear over the upper 95% of the dynamic range, the deviations at lower energies can be attributed to the shortcomings of the PMT. Compared to smaller volume crystals, no substantial degradation in light output, or alternately, energy resolution has been observed. For example, at 662 keV, an energy resolution of 3% FWHM was measured. Experiments with monoenergetic protons show that they create approximately half the light output of gamma-rays. r

The Tanzania Food and Drugs Authority piloted the use of Minilab kits, a thin-layer-chromatographic based drug quality testing technique, in a two-tier quality assurance program. The program is intended to improve testing capacity with timely screening of the quality of medicines as they enter the market. After 1 week training of inspectors on Minilab screening techniques, they were stationed at key Ports-of-Entry (POE) to screen the quality of imported medicines. In addition, three non-Ports-of-Entry centres were established to screen samples collected during Post-Marketing-Surveillance. Standard operating procedures (SOPs) were developed to structure and standardize the implementation process. Over 1200 samples were tested using the Minilab outside the central quality control laboratory (QCL), almost doubling the previous testing capacity. The program contributed to increased regulatory reach and visibility of the Authority throughout the country, serving as a deterrent against entry of substandard medicines into market. The use of Minilab for quality screening was inexpensive and provided a high sample throughput. However, it suffers from the limitation that it can reliably detect only grossly substandard or wrong drug samples and therefore, it should not be used as an independent testing resource but in conjunction with a full-service quality control laboratory capable of auditing reported substandard results.

Maternal mortality from postpartum hemorrhage remains high globally, in large part because women give birth in rural communities where unskilled (traditional birth attendants) provide care for delivering mothers. Traditional attendants are neither trained nor equipped to recognize or manage postpartum hemorrhage as a life-threatening emergent condition. Recommended treatment includes using uterotonic agents and physical manipulation to aid uterine contraction. In resource-limited areas where Obstetric first aid may be the only care option, physical methods such as bimanual uterine compression are easily taught, highly practical and if performed correctly, highly effective. A simulator with objective performance feedback was designed to teach skilled and unskilled birth attendants to perform the technique. To evaluate the impact of simulation-based training on the ability of birth attendants to correctly perform bimanual compression in response to postpartum hemorrhage from uterine a...

The extant population of Hawaiian monk seal (Monachus schauinslandi) numbers around 1,00 distributed among six island atolls in the remote Northwestern Hawaiian Islands (NWHI) and at several small, emerging colonies on the Main Hawaiian Islands. Demographic studies have identified poor juvenile survival as the ultimate primary cause of substantial declines at all colonies and of slow recent recovery at some. Variable foraging success may be a key proximate effect, but the knowledge of habitat needs of foraging monk seals has not been adequate to test that hypothesis nor to provide management with the necessary information to address resource conservation issues. We documented the geographic and vertical foraging patterns of 1 Hawaiian monk seals from all six NWHI breeding colonies from 1 through 00 to describe the marine habitats that may be key to the species' viability. We found that seals foraged extensively within barrier reefs of the atolls and on the leeward slopes of reefs and islands at all colony sites. They also ranged away from these sites along the Hawaiian Islands Archipelago submarine ridge to most nearby seamounts and submerged reefs and banks. Most dives were less than 10 m deep, though dives of some seals exceeded 0 m. Suitable foraging habitat may be a resource limiting the population of monk seals in the NWHI. Moreover, the foraging biogeography of Hawaiian monk seals may vary spatially and temporally with variation in the extent of physical substrate, prey community composition and species' abundance, and demographic composition of seal colonies.

This review reports on why is there still rabies in the world?-an emerging microbial and global health threat. Rabies remains an important public health issue in the world. While rabies has been controlled throughout most of the developed world, it remains a significant burden in developing countries, particularly in Africa and Asia. Although industrialized countries have been able to contain recent outbreaks, many resource-limited and transitioning countries have not been able to react adequately. Although, a vaccinepreventable disease, the annual number of human deaths caused by rabies is estimated to be 35,000 per year, mostly in Africa, Asia and Latin America. Though, dogs have been identified as being primarily responsible for the transmission of rabies in human and other domestic animals, known pathogenesis and available data suggest that all or nearly all cases of human rabies attributable to bats were transmitted by bat bites that were minimized or unrecognized by the patients. One of the key for controlling rabies is to focus on the animal reservoir. The high incidence of rabies in some country led to numerous concerns attributed to a potential carrier-dog phenomenon, undocumented transmission of rabies virus from wildlife to dogs, counterfeit vaccines, vaccine mismatching and seroconversion testing in patients after their completion of postexposure prophylaxis. However, the number of reported human rabies cases, particularly in Africa, greatly underestimates the true effects of the disease. Contributing factors include failure to seek treatment at healthcare facilities, failure to make a laboratory diagnosis and failure to report the disease. The disconnection between human and dog rabies in developing world reflects a lack of awareness of the concept of one medicine, or health without regard to species, in approaches to rabies control in the public health system. Another factor contributing to the endemicity of rabies in the world could be attributed to low vaccine coverage. Although there are many factors that contribute to the epidemic or endemic nature of rabies in the world, the single most important factor is the failure to immunize domestic dogs, which transmit rabies to humans. Regional and local disease resurgence occurs, due in part to a combination of political and economic instability, environmental perturbations and shifting government priorities. Indeed rabies is a widely distributed zoonotic disease of major public-health importance and an emerging as well as re-emerging microbial and global health threat but a preventable problem. Surveillance strategies for rabies and other rabies-ralated viruses in the world, particularly Africa must be improved to better understand the epidemiology of this virus and to make informed decisions on future vaccine strategies.

Adaptive radiations are an important source of biodiversity, but resolving which ecological pressures seed these processes in natural systems remains difficult. Here the adaptive radiation among Telmatherina , a genus of freshwater fish endemic to an ancient lake in central Sulawesi, Indonesia, was examined to determine its causal root. We demonstrate that all Telmatherina in this lake can be categorized into three lineages each possessing specialized skull shapes and pharyngeal jaw bones allowing them to exploit different resources. These data demonstrate a natural example of how resource partitioning has likely initiated adaptive radiation in a resource limited environment.

This article presents the results of a survey sent to Evaluation Use Topical Interest Group (TIG) members for the purpose of ascertaining their perceptions about and experiences with evaluation use. Fifty-four percent (n = 282) of the 530 members surveyed responded. These respondents agree that the major purposes of evaluation are to facilitate organizational learning, provide information for decision making, improve programs, and determine the merit or worth of the evaluand. Performance-results oriented

This paper uses empirical field research to examine whether short-term best practice interventions (BPIs) can lead to improvements that are sustained in the long term. In addition, this research investigates the implied conflict between striving for short-term results and achieving long-term development of capabilities. It also examines the tension between the lack of resources of the typical small and medium sized enterprise (SME) users of BPIs and the time required to develop a critical mass of capability. A longitudinal case-based study of eight SME contexts examined BPI outcomes and factors leading to short-and long-term success and sustaining best practices. The research identifies factors related to the intervention context, implementation and change-agent approach. The data indicate that in resource-limited SMEs BPIs are limited in their ability to develop adequate capability for long-term change.

The security of operating systems is a main concern for all computer users and programmers. Operating system developers have addressed this concern in different ways, resulting in a number of security improvements for existing operating systems. In our paper, we report our findings from a case study of SELinux and grsecurity, two prominent Linux kernel enhancements. In implementing Mandatory Access Control (MAC), SELinux is a MAC mechanism that provides domain type enforcement and role-based access control, while grsecurity employs Access Control Lists (ACLs). We describe and quantify the differences between the two, in terms of ease of use, installation, MAC implementation, and performance. We determine that SELinux has a stronger MAC implementation, while grsecurity is simpler to use and offers other exclusive features, such as address space protection and resource limiting.

This review paper first discusses the needs for fundamental changes in the energy system for major efficiency improvements in terms of global resource limitation and sustainable development. Major improvement in energy efficiency of electric power plants and transportation vehicles is needed to enable the world to meet the energy demands at lower rate of energy consumption with corresponding reduction in pollutant and CO 2 emissions. A brief overview will then be given on principle and advantages of different types of low-temperature and high-temperature fuel cells. Fuel cells are intrinsically much more energy-efficient, and could achieve as high as 70-80% system efficiency (including heat utilization) in electric power plants using solid oxide fuel cells (SOFC, versus the current efficiency of 30-37% via combustion), and 40-50% efficiency for transportation using proton-exchange membrane fuel cells (PEMFC) or solid oxide fuel cells (versus the current efficiency of 20-35% with internal combustion (IC) engines). The technical discussions will focus on fuel processing for fuel cell applications in the 21st century. The strategies and options of fuel processors depend on the type of fuel cells and applications. Among the low-temperature fuel cells, proton-exchange membrane fuel cells require H 2 as the fuel and thus nearly CO-free and sulfur-free gas feed must be produced from fuel processor. High-temperature fuel cells such as solid oxide fuel cells can use both CO and H 2 as fuel, and thus fuel processing can be achieved in less steps. Hydrocarbon fuels and alcohol fuels can both be used as fuels for reforming on-site or on-board. Alcohol fuels have the advantages of being ultra-clean and sulfur-free and can be reformed at lower temperatures, but hydrocarbon fuels have the advantages of existing infrastructure of production and distribution and higher energy density. Further research and development on fuel processing are necessary for improved energy efficiency and reduced size of fuel processor. More effective ways for on-site or on-board deep removal of sulfur before and after fuel reforming, and more energy-efficient and stable catalysts and processes for reforming hydrocarbon fuels are necessary for both high-temperature and low-temperature fuel cells. In addition, more active and robust (non-pyrophoric) catalysts for water-gas-shift (WGS) reactions, more selective and active catalysts for preferential CO oxidation at lower temperature, more CO-tolerant anode catalysts would contribute significantly to development and implementation of low-temperature fuel cells, particularly proton-exchange membrane fuel cells. In addition, more work is required in the area of electrode catalysis * : S 0 9 2 0 -5 8 6 1 ( 0 2 ) 0 0 2 3 1 -6 mate, especially CO and sulfur species.

6 Abstract: This review reports on why is there still rabies in the world?-an emerging microbial and global health threat. Rabies remains an important public health issue in the world. While rabies has been controlled throughout most of the developed world, it remains a significant burden in developing countries, particularly in Africa and Asia. Although industrialized countries have been able

HIV/AIDS and food insecurity are two of the leading causes of morbidity and mortality in sub-Saharan Africa, with each heightening the vulnerability to, and worsening the severity of, the other. Less research has focused on the social determinants of food insecurity in resource-limited settings, including social support and HIV-related stigma. In this study, we analyzed data from a cohort of 456 persons from the Uganda AIDS Rural Treatment Outcomes study, an ongoing prospective cohort of persons living with HIV/AIDS (PLWHA) initiating HIV antiretroviral therapy in Mbarara, Uganda. Quarterly data were collected by structured interviews. The primary outcome, food insecurity, was measured with the Household Food Insecurity Access Scale. Key covariates of interest included social support, internalized HIV-related stigma, HIV-related enacted stigma, and disclosure of HIV serostatus. Severe food insecurity was highly prevalent overall (38%) and more prevalent among women than among men. Social support, HIV disclosure, and internalized HIV-related stigma were associated with food insecurity; these associations persisted after adjusting for household wealth, employment status, and other previously identified correlates of food insecurity. The adverse effects of internalized stigma persisted in a lagged specification, and the beneficial effect of social support further persisted after the inclusion of fixed effects. International organizations have increasingly advocated for addressing food insecurity as part of HIV/AIDS programming to improve morbidity and mortality. This study provides quantitative evidence on social determinants of food insecurity among PLWHA in resource-limited settings and suggests points of intervention. These findings also indicate that structural interventions to improve social support and/or decrease HIV-related stigma may also improve the food security of PLWHA.

Introduction: The WHO clinical guidelines for HIV/AIDS are widely used in resource limited settings to represent the gold standard of CD4 counts for antiviral therapy initiation. The utility of the WHO-defined stage 1 and 2 clinical factors used in WHO HIV/AIDS clinical staging in predicting low CD4 cell count has not been established in Uganda. Although the WHO staging has shown low sensitivity for predicting CD4,200cells/mm 3 , it has not been evaluated at for CD4 cut-offs of ,250cells/mm 3 or ,350 cells/mm 3 .

published by Oxford University Press in 1983, and Indonesian Marine Capture Fisheries, a 1987 ICLARM publication which he co-authored with two Indonesian colleagues. His primary research interests are in the political economy of development and the sociology of natural resources and the environment.

The Gouldian Finch (Erythrura gouldiae) has experienced significant decline in population and the extent of its range over the past 40 years, which has generally been attributed to the availability of suitable foraging habitat. Less research, however, has investigated the suitability or availability of breeding habitat of the species. Gouldian Finches are obligate cavity nesters, and a recent study has shown that they select nest-sites non-randomly based on structural characteristics of the cavity. Here we investigated the relative effects of different environmental factors on the spatial distribution of Gouldian Finch nests at two different scales. At the broader, landscape scale (over~60 km 2 ), the strongest predictor of nesting density at a site was the abundance of suitable nest-sites. At the finer scale (~1 km 2 ), no single factor explained the variation in location of nest-sites. Gouldian Finches require areas of habitat characterised by high densities of suitable nest-sites (tree-cavities). Within these patches, individuals are potentially selecting nest-sites based on the morphometry of cavities rather than landscape features such as topography, vegetation or proximity to water. Our findings should be integrated with studies of feeding and habitat requirements in the non-breeding season, with the aim of constructing holistic and predictive habitatsuitability models for this endangered species.

This study explores global energy demand, and hydrogen&#x27;s role, over the 21st century. It considers four illustrative cases: a high (1000EJ) and a low (300EJ) energy future, and for each of these conditions, a high (80%) and low (20%) fossil fuel energy share. We argue that neither high energy future is probable, because of resource limitations, and rising energy, environmental and money costs per unit of delivered energy as annual energy demand rises far beyond present levels. The low energy/low fossil case is most likely, ...

Background: As in other resource limited settings, the Ministry of Health in Zambia is challenged to make affordable and acceptable PMTCT interventions accessible and available. With a 14.3% HIV prevalence, the MOH estimates over one million people are HIV positive in Zambia. Approximately 500,000 children are born annually in Zambia and 40,000 acquire the infection vertically each year if no intervention is offered. This study sought to review uptake of prevention of mother-to-child (PMTCT) services in a resource-limited setting following the introduction of context-specific interventions. Methods: Interventions to improve PMTCT uptake were introduced into 38 sites providing PMTCT services in Zambia in July 2005. Baseline and follow up service data were collected on a monthly basis through September 2008. Data was checked for internal and external consistency using logic built into databases used for data management. Data audits were conducted to determine accuracy and reliability. Trends were analyzed pre-and post-intervention. Results: Uptake among pregnant women increased across the 13 quarters (39 months) of observation, particularly in the case of acceptance of counseling and HIV testing from 45% to 90% (p value = 0.00) in the first year and 99% by year 3 (p value = 0.00). Receipt of complete course of antiretroviral (ARV) prophylaxis increased from 29% to 66% (p = 0.00) in the first year and 97% by year 3 (p value = 0.00). There was also significant improvement in the percentage of HIV positive pregnant women referred for clinical care. Conclusions: Uptake of PMTCT services in resource-limited settings can be improved by utilizing innovative alternatives to mitigate the effects of human resource shortage such as by providing technical assistance and mentorship beyond regular training courses, integrating PMTCT services into existing maternal and child health structures, addressing information gaps, mobilizing traditional and opinion leaders and building strong relationships with the government. These health system based approaches provide a sustainable improvement in the capacity and uptake of services.

Quinine remains an important anti-malarial drug almost 400 years after its effectiveness was first documented. However, its continued use is challenged by its poor tolerability, poor compliance with complex dosing regimens, and the availability of more efficacious anti-malarial drugs. This article reviews the historical role of quinine, considers its current usage and provides insight into its appropriate future use in the treatment of malaria. In light of recent research findings intravenous artesunate should be the first-line drug for severe malaria, with quinine as an alternative. The role of rectal quinine as pre-referral treatment for severe malaria has not been fully explored, but it remains a promising intervention. In pregnancy, quinine continues to play a critical role in the management of malaria, especially in the first trimester, and it will remain a mainstay of treatment until safer alternatives become available. For uncomplicated malaria, artemisinin-based combination therapy (ACT) offers a better option than quinine though the difficulty of maintaining a steady supply of ACT in resource-limited settings renders the rapid withdrawal of quinine for uncomplicated malaria cases risky. The best approach would be to identify solutions to ACT stock-outs, maintain quinine in case of ACT stock-outs, and evaluate strategies for improving quinine treatment outcomes by combining it with antibiotics. In HIV and TB infected populations, concerns about potential interactions between quinine and antiretroviral and anti-tuberculosis drugs exist, and these will need further research and pharmacovigilance.

This paper examines the integration of computational complexity into game theoretic models. The example focused on is the Prisoner’s Dilemma, repeated for a finite length of time. We show that a minimal bound on the players’ computational ability is sufficient to enable cooperative behavior. In addition, a variant of the repeated Prisoner’s Dilemma game is suggested, in which players have the choice of opting out. This modification enriches the game and suggests dominance of cooperative strategies. Competitive analysis is suggested as a tool for investigating sub-optimal (but computationally tractable) strategies and game theoretic models in general. Using competitive analysis, it is shown that for bounded players, a sub-optimal strategy might be the optimal choice, given resource limitations.

Since the first cases of infant HIV infection were described in the early 1980s, significant progress has been made in our understanding of risk factors for mother-to-child transmission (MTCT) of HIV as well as effective interventions to prevent transmission. MTCT of the human immunodeficiency virus type-1 (HIV-1) can occur during pregnancy particularly in the third trimester, during the intrapartum period, and for infants exposed to HIV, who are breastfed, throughout the period of lactation. 1 Before the availability of antiretroviral and obstetric interventions, about 1 in 4 infants born to women infected with HIV became infected. Among these infected infants, 50% to 60% of transmission occurred around the time of labor or delivery based on newborn infants exposed to HIV having negative cord blood or newborn polymerase chain reaction (PCR) tests that subsequently became positive within the first weeks of life. 2 Among HIV-infected breastfeeding populations, about 20% to 25% of infections occurred in utero based on positive PCRs at birth; 35% to 50% intrapartum; and another 25% to 35% of infants negative at birth and in the first 6 weeks became infected later, presumably as a result of transmission through breast milk. 1

This study assessed the performance of a rapid, low-cost, colorimetric method, the resazurin microtitre assay (REMA) plate method, for the detection of resistance to isoniazid and rifampicin in 136 clinical isolates of Mycobacterium tuberculosis from two hospitals in Algiers. MICs were determined and the results were compared with those obtained with the conventional proportion method on Lowenstein-Jensen medium. Excellent results

Ultrasound has great potential as an imaging technology in resource-limited environments. We present a novel tele-ultrasound approach designed to realize that potential by connecting a remote technician to a radiologist. Our preliminary system, based on open-source software and commercial off-the-shelf hardware, uses custom software and a satellite Internet connection to create this link. We also present the results of testing this system in both laboratory and real-world environments.

The problem of optimal policy formulation for teams of resource-limited agents in stochastic environments is composed of two strongly-coupled subproblems: a resource allocation problem and a policy optimization problem. We show how to combine the two problems into a single constrained optimization problem that yields optimal resource allocations and policies that are optimal under these allocations. We model the system as a multiagent Markov decision process (MDP), with social welfare of the group as the optimization criterion. The straightforward approach of modeling both the resource allocation and the actual operation of the agents as a multiagent MDP on the joint state and action spaces of all agents is not feasible, because of the exponential increase in the size of the state space. As an alternative, we describe a technique that exploits problem structure by recognizing that agents are only loosely-coupled via the shared resource constraints. This allows us to formulate a constrained policy optimization problem that yields optimal policies among the class of realizable ones given the shared resource limitations. Although our complexity analysis shows the constrained optimization problem to be NP-complete, our results demonstrate that, by exploiting problem structure and via a reduction to a mixed integer program, we are able to solve problems orders of magnitude larger than what is possible using a traditional multiagent MDP formulation.

Browse plants play an important role in providing fodder for ruminants in most parts of the World. However, the presence of tannins and other phenolic compounds in a large number of these feed resources limits their utilization as animal feed. This paper presents the nutritive value of some browse species based on their chemical composition (nitrogen, polyphenolics and neutral detergent fibre (NDF) content), dry matter (DM) degradability in sacco and gas production in vitro including the effect of the phenolic binding compound, polyethyleneglycol-4000 (PEG 4000), on in vitro gas production. The browse species evaluated were Calluna vulgaris (heather), Sarothamnus scoparius (broom), Ulex europaeus (gorse) and Chamaecytisus palmensis (tagasaste).