Wasteland energy-scapes: a comparative energy flow analysis of India's biofuel and biomass economies

Through a comparative energy flow analysis, this paper examines the energy security impacts of growing biofuels on wastelands in South India. India's National Policy on Biofuels claims that wastelands are well suited for biofuel production because they are empty and unused. However, in rural Tamil Nadu, a Prosopis juliflora fuelwood energy economy already exists on these lands and services a mix of rural and urban consumers at household and industrial levels. This Prosopis economy currently provides 2.5–10.3 times more useful energy than would the government's proposed Jatropha curcas biodiesel economy, depending on Jatropha by-product usage. Contrary to the government's claims, growing biofuels on wastelands can weaken, rather than improve, the country's energy security. Further, replacing Prosopis with Jatropha could engender changes in economic and property relations that could further weaken energy security. These findings are not specific to rural Tamil Nadu as Prosopis is widely used as a fuelwood throughout Asia and Africa. Calls to ‘develop’ degraded lands through biofuel promotion similarly exist in these regions. This study underscores the importance of analyzing wasteland-centered biofuel policies at local levels in order to better understand the changes in human–environment relationships resulting from this policy push

IMPACTS OF GREENHOUSE GAS AND PARTICULATE EMISSIONS FROM WOODFUEL PRODUCTION AND END-USE IN SUB-SAHARAN AFRICA

Household energy in sub-Saharan Africa is largely derived from woodfuels burned in simple stoves with poor combustion characteristics. These devices emit products of incomplete combustion [PICs] that both damage human health and negatively impact the atmospheric radiation budget. We use empirical studies and published emission factors to estimate the pollution associated with production, distribution and end-use of common household fuels and assess the impacts of these emissions on public health and the global environment. We find that each meal cooked with charcoal has 2-10 times the global warming effect of cooking the same meal with firewood and 5-16 times the effect of cooking the same meal with kerosene or LPG depending on the gases that are included in the analysis and the degree to which wood is allowed to regenerate. However, although charcoal is worse than other fuels with respect to GHG emissions, it can lead to reductions in concentrations of pollutants like particulate matter (PM). Concentrations of PM in households using charcoal were found to be 88 percent lower than households using open wood fires (charcoal: 465±387 µg/m3 ; open wood fires: 3764±714 µg/m3 (mean±95% CI)). Two years of health data collected from Kenyan families using wood and charcoal shows that charcoal users experienced 44-65 percent fewer cases of acute lower respiratory infection (ALRI) compared to wood users. Understanding the costs and benefits of household energy options is an important step in designing effective energy policies

Biocombustíveis e a economia verde inclusiva: buscando o desenvolvimento regional sustentável na Amazônia Legal Brasileira

Biofuel production has been greatly discussed in Brazil. In 2004, some debates lead the country to develop new policies and implement the National Biodiesel Use and Production Program (PNPB), with the intent to increase the share of renewable energy and foster sustainable regional development. In this context, the present study aims to assess the linkages between family farmer’s living standard and the adoption of oil seed activity in northern Brazil, in a region of transition between the Cerrado (Brazilian savanna) and the Amazon rain forest. Ranges of socio-economic indicators were collected among smallholders who cultivate soybean. A fuzzy logic set theory based on living standard criteria and a non-linear probit model was applied to assess the inclusion of poor rural families in the biodiesel chain. Preliminary results point towards a negative relation between the family degree of deprivation and adoption of oil seed activity, for the soybean production.A produção de biocombustíveis tem sido fortemente discutida no Brasil, levando o País a desenvolver políticas e implantar, no ano de 2004, o Programa Nacional de Produção e Uso de Biodiesel (PNPB), a fim de aumentar a participação de energias renováveis, bem como fomentar o desenvolvimento regional sustentável. Nesse contexto, o presente estudo busca avaliar a relação entre a condição de vida dos agricultores e a adoção do cultivo de oleaginosas no norte do Brasil, em uma região de transição entre o Cerrado e a Floresta Amazônica. Uma gama de indicadores socioeconômicos foi coletada entre os agricultores que cultivam soja na região. A teoria dos conjuntos fuzzy baseada na condição de vida dos agricultores e um modelo não linear probit foram utilizados para avaliar a inclusão de famílias rurais pobres na cadeia do biodiesel. Os resultados preliminares mostram uma relação negativa entre o nível de privação das famílias e a adoção do cultivo de soja

Wasteland energy-scapes: a comparative energy flow analysis of India's biofuel and biomass economies

Through a comparative energy flow analysis, this paper examines the energy security impacts of growing biofuels on wastelands in South India. India's National Policy on Biofuels claims that wastelands are well suited for biofuel production because they are empty and unused. However, in rural Tamil Nadu, a Prosopis juliflora fuelwood energy economy already exists on these lands and services a mix of rural and urban consumers at household and industrial levels. This Prosopis economy currently provides 2.5–10.3 times more useful energy than would the government's proposed Jatropha curcas biodiesel economy, depending on Jatropha by-product usage. Contrary to the government's claims, growing biofuels on wastelands can weaken, rather than improve, the country's energy security. Further, replacing Prosopis with Jatropha could engender changes in economic and property relations that could further weaken energy security. These findings are not specific to rural Tamil Nadu as Prosopis is widely used as a fuelwood throughout Asia and Africa. Calls to ‘develop’ degraded lands through biofuel promotion similarly exist in these regions. This study underscores the importance of analyzing wasteland-centered biofuel policies at local levels in order to better understand the changes in human–environment relationships resulting from this policy push

The charcoal trap: Miombo forests and the energy needs of people

<p>Abstract</p> <p>Background</p> <p>This study evaluates the carbon dioxide and other greenhouse gas fluxes to the atmosphere resulting from charcoal production in Zambia. It combines new biomass and flux data from a study, that was conducted in a <it>miombo </it>woodland within the Kataba Forest Reserve in the Western Province of Zambia, with data from other studies.</p> <p>Results</p> <p>The measurements at Kataba compared protected area (3 plots) with a highly disturbed plot outside the forest reserve and showed considerably reduced biomass after logging for charcoal production. The average aboveground biomass content of the reserve (Plots 2-4) was around 150 t ha^-1, while the disturbed plot only contained 24 t ha^-1. Soil carbon was not reduced significantly in the disturbed plot. Two years of eddy covariance measurements resulted in net ecosystem exchange values of -17 ± 31 g C m^-2y^-1, in the first and 90 ± 16 g C m^-2in the second year. Thus, on the basis of these two years of measurement, there is no evidence that the <it>miombo </it>woodland at Kataba represents a present-day carbon sink. At the country level, it is likely that deforestation for charcoal production currently leads to a per capita emission rate of 2 - 3 t CO₂y^-1. This is due to poor forest regeneration, although the resilience of <it>miombo </it>woodlands is high. Better post-harvest management could change this situation.</p> <p>Conclusions</p> <p>We argue that protection of <it>miombo </it>woodlands has to account for the energy demands of the population. The production at national scale that we estimated converts into 10,000 - 15,000 GWh y^-1of energy in the charcoal. The term "Charcoal Trap" we introduce, describes the fact that this energy supply has to be substituted when woodlands are protected. One possible solution, a shift in energy supply from charcoal to electricity, would reduce the pressure of forests but requires high investments into grid and power generation. Since Zambia currently cannot generate this money by itself, the country will remain locked in the charcoal trap such as many other of its African neighbours. The question arises whether and how money and technology transfer to increase regenerative electrical power generation should become part of a post-Kyoto process. Furthermore, better inventory data are urgently required to improve knowledge about the current state of the woodland usage and recovery. Net greenhouse gas emissions could be reduced substantially by improving the post-harvest management, charcoal production technology and/or providing alternative energy supply.</p

P2X7 in Cancer: From Molecular Mechanisms to Therapeutics

P2X7 is a transmembrane receptor expressed in multiple cell types including neurons, dendritic cells, macrophages, monocytes, B and T cells where it can drive a wide range of physiological responses from pain transduction to immune response. Upon activation by its main ligand, extracellular ATP, P2X7 can form a nonselective channel for cations to enter the cell. Prolonged activation of P2X7, via high levels of extracellular ATP over an extended time period can lead to the formation of a macropore, leading to depolarization of the plasma membrane and ultimately to cell death. Thus, dependent on its activation state, P2X7 can either drive cell survival and proliferation, or induce cell death. In cancer, P2X7 has been shown to have a broad range of functions, including playing key roles in the development and spread of tumor cells. It is therefore unsurprising that P2X7 has been reported to be upregulated in several malignancies. Critically, ATP is present at high extracellular concentrations in the tumor microenvironment (TME) compared to levels observed in normal tissues. These high levels of ATP should present a survival challenge for cancer cells, potentially leading to constitutive receptor activation, prolonged macropore formation and ultimately to cell death. Therefore, to deliver the proven advantages for P2X7 in driving tumor survival and metastatic potential, the P2X7 macropore must be tightly controlled while retaining other functions. Studies have shown that commonly expressed P2X7 splice variants, distinct SNPs and post-translational receptor modifications can impair the capacity of P2X7 to open the macropore. These receptor modifications and potentially others may ultimately protect cancer cells from the negative consequences associated with constitutive activation of P2X7. Significantly, the effects of both P2X7 agonists and antagonists in preclinical tumor models of cancer demonstrate the potential for agents modifying P2X7 function, to provide innovative cancer therapies. This review summarizes recent advances in understanding of the structure and functions of P2X7 and how these impact P2X7 roles in cancer progression. We also review potential therapeutic approaches directed against P2X7

A 'snip' in time: what is the best age to circumcise?

<p>Abstract</p> <p>Background</p> <p>Circumcision is a common procedure, but regional and societal attitudes differ on whether there is a need for a male to be circumcised and, if so, at what age. This is an important issue for many parents, but also pediatricians, other doctors, policy makers, public health authorities, medical bodies, and males themselves.</p> <p>Discussion</p> <p>We show here that infancy is an optimal time for clinical circumcision because an infant's low mobility facilitates the use of local anesthesia, sutures are not required, healing is quick, cosmetic outcome is usually excellent, costs are minimal, and complications are uncommon. The benefits of infant circumcision include prevention of urinary tract infections (a cause of renal scarring), reduction in risk of inflammatory foreskin conditions such as balanoposthitis, foreskin injuries, phimosis and paraphimosis. When the boy later becomes sexually active he has substantial protection against risk of HIV and other viral sexually transmitted infections such as genital herpes and oncogenic human papillomavirus, as well as penile cancer. The risk of cervical cancer in his female partner(s) is also reduced. Circumcision in adolescence or adulthood may evoke a fear of pain, penile damage or reduced sexual pleasure, even though unfounded. Time off work or school will be needed, cost is much greater, as are risks of complications, healing is slower, and stitches or tissue glue must be used.</p> <p>Summary</p> <p>Infant circumcision is safe, simple, convenient and cost-effective. The available evidence strongly supports infancy as the optimal time for circumcision.</p