Bioenergy production and food security in Africa

Food and energy insecurities are the two greatest problems in Africa. Per capita energy consumption in Africa is less than 10% of that of United States of America while 18 out of 23 countries where starvation and malnutrition are most severe in the world are in Africa. Although various African governments have been making efforts to boast agricultural productivity, crop yields remain very low. Most governments do not even have accurate statistics on the number, location and types of crops produced by smallholder farmers that produce more than 80% of foods in Africa. This makes it very difficult to plan and implement any government support to the farmers. Sub-Saharan African countries have very high potential for production of different forms of bioenergy because the climatic conditions favour production of many energy crops. The big question has always been whether to produce bioenergy from food crops, especially in Africa with high acute food shortages. Large scale production of bioenergy may lead to competition with food crops for land, labour and other agricultural inputs. However, data from various sources indicate that Africa has abundant and underutilized arable land which can be effectively used for mass production of energy crops. Furthermore, shortage of labour cannot be a problem given the present very high rate of unemployment in most African countries. The benefits of bioenergy production in Africa outweigh the possible adverse effects on food security. Bioenergy production will create demand for, and stabilize the prices for crops, thereby increasing the earning of the farmers. This will in turn, facilitate industrialization in other sectors of economy through provision of affordable, renewable and clean energy. In order to minimize possible negative effects of bioenergy production on food security, land allocation for energy crop production can be regulated. Energy security cannot be separated from food security and the two should be seen as complimentary rather than as competitors.Key words: Bioenergy production, food security, energy

The universe out of a monopole in the laboratory?

To explore the possibility that an inflationary universe can be created out of a stable particle in the laboratory, we consider the classical and quantum dynamics of a magnetic monopole in the thin-shell approximation. Classically there are three types of solutions: stable, collapsing and inflating monopoles. We argue that the transition from a stable monopole to an inflating one could occur either by collision with a domain wall or by quantum tunneling.Comment: to appear in Phys. Rev. D with changing title into "Is it possible to create a universe out of a monopole in the laboratory?", text and figures revised, 21 pages, 6 figure

Facile Photo-Oxidation of Alcohols by a Flavin with a Metal-Chelation Site

A new flavin molecule with a metal-chelation site has been applied to photo-oxidation of alcohols: it is 2, 4, 7-trimethyl-10-benzylquino [8, 7-g] pteridine-9, 11 (7H, 10H) -dione (1) which has both an isoalloxazine structure and a phenathroline-like structure within a molecule. In contrast to conventional flavins which do not exhibit any measurable affinity toward redox-inactive transition metal ions, 1 formed stable complexes with most heavy metal ions in acetonitrile probably by means of a flavin → metal charge transfer. Photooxidation of alcohols by 1 was efficiently accelerated in the presence of Mg(II) and Zn(II), the k1 (pseudo-first-order rate constant) being greater by 5.1-7l fold than those in the absence of metal ions. Such a marked rate increase was not observed for 3-methyl-10-ethylisoalloxazine used as a reference flavin. The aerobic photo-oxidation of benzyl alcohol by the 1・Zn(II) complex served as a light-mediated recycle oxidation catalyst. These results indicate that the flavin with a metal-chelation site is not only useful synthetically as a recycle-type oxidation catalyst but also capable of mimicking the flavin-metal interactions important in metalloflavoproteins

Modulation of Emotion by Cognitive Activity

While emotions themselves are beneficial for our survival, they are also the targets to be regulated appropriately to adapt to social environments. Previous studies have demonstrated that cognitive strategies such as cognitive reappraisal and expressive suppression can effectively enhance and attenuate emotions. Such cognitive strategies of emotion regulation are based on cortical modulation of sub-cortical emotion-related brain regions. Though in the prior studies emotion regulation was conducted in parallel with or after the emotion elicitation, a series of our studies showed that prior cognitive activities can automatically and unintentionally attenuate subsequent emotional responses. In this article, after reviewing the previous findings about emotion regulation, we introduce our empirical findings showing that cognitive activities where the neural system of emotion regulation would be recruited can unintentionally and automatically dampen psychological and physiological emotional responses. Finally, we propose possible neural mechanisms underlying modulation of emotion by cognitive activity

Perturbative Analysis of a Stationary Magnetosphere in an Extreme Black Hole Spacetime : On the Meissner-like Effect of an Extreme Black Hole

It is known that the Meissner-like effect is seen in a magnetosphere without an electric current in black hole spacetime: no non-monopole component of magnetic flux penetrates the event horizon if the black hole is extreme. In this paper, in order to see how an electric current affects the Meissner-like effect, we study a force-free electromagnetic system in a static and spherically symmetric extreme black hole spacetime. By assuming that the rotational angular velocity of the magnetic field is very small, we construct a perturbative solution for the Grad-Shafranov equation, which is the basic equation to determine a stationary, axisymmetric electromagnetic field with a force-free electric current. Our perturbation analysis reveals that, if an electric current exists, higher multipole components may be superposed upon the monopole component on the event horizon, even if the black hole is extreme.Comment: 30 pages, 3 figure

A Genetic Variant in the IL-17 Promoter Is Functionally Associated with Acute Graft-Versus-Host Disease after Unrelated Bone Marrow Transplantation

Interleukin IL-17 is a proinflammatory cytokine that has been implicated in the pathogenesis of various autoimmune diseases. The single nucleotide polymorphism (SNP), rs2275913, in the promoter region of the IL-17 gene is associated with susceptibility to ulcerative colitis. When we examined the impact of rs2275913 in a cohort consisting of 438 pairs of patients and their unrelated donors transplanted through the Japan Marrow Donor Program, the donor IL-17 197A allele was found to be associated with a higher risk of acute graft-versus-host disease (GVHD; hazard ratio [HR], 1.46; 95% confidence interval [CI], 1.00 to 2.13; P = 0.05). Next, we investigated the functional relevance of the rs2275913 SNP. In vitro stimulated T cells from healthy individuals possessing the 197A allele produced significantly more IL-17 than those without the 197A allele. In a gene reporter assay, the 197A allele construct induced higher luciferase activity than the 197G allele, and the difference was higher in the presence of T cell receptor activation and was abrogated by cyclosporine treatment. Moreover, the 197A allele displayed a higher affinity for the nuclear factor activated T cells (NFAT), a critical transcription factor involved in IL-17 regulation. These findings substantiate the functional relevance of the rs2275913 polymorphism and indicate that the higher IL-17 secretion by individuals with the 197A allele likely accounts for their increased risk for acute GVHD and certain autoimmune diseases

Inhomogeneity of Spatial Curvature for Inflation

We study how the initial inhomogeneities of the spatial curvature affect the onset of inflation in the closed universe. We consider a cosmological model which contains a radiation and a cosmological constant. In order to treat the inhomogeneities in the closed universe, we improve the long wavelength approximation such that the non-small spatial curvature is tractable in the lowest order. Using the improved scheme, we show how large inhomogeneities of the spatial curvature prevent the occurrence of inflation.Comment: 17 pages, revtex, 6 figures included using eps