827 research outputs found
Proposed strategy for a regional exchange rate arrangement in post-crisis East Asia
After discussing major conceptual, and empirical issues relevant to the exchange rate policies of East Asian countries, the authors propose a regional exchange rate arrangement designed to promote intra-regional exchange rate stability, and regional economic growth. They argue that: 1) For developing countries, exchange rate volatility tends to significantly hurt trade and investment, making it inadvisable to adopt a system of freely floating exchange rates. 2) Given the high share of intra-regional trade, and the similarity of trade composition in East Asia, exchange rate policy should be directed toward maintaining intra-regional exchange rate stability, to promote trade, investment, and economic growth. 3) the current policy of maintaining exchange rate stability against U.S. dollar as an informal, uncoordinated mechanisms for ensuring intra-regional exchange rate stability is sub-optimal. A pragmatic policy option - conducive to a more robust framework for cooperation in monetary, and exchange rate policy - wold be a coordinated action to shift the target of nominal exchange rate stability, to a basket of tri-polar currencies (the U.S. dollar, the Japanese yen, and the Euro). This alternative would better reflect the region's diverse structure of trade, and foreign direct investment.The authors envision no rigid peg. Instead, at least initially, each country could choose its own formal exchange rate arrangement - be it currency board, a crawling peg, or a basket peg with wide margins. At times of crisis, the peg might be temporarily suspended, subject to the rule that the exchange rate would be restored to the original level as soon as practical. Only in extreme circumstances, would the level be adjusted to reflect new equilibrium conditions.Environmental Economics&Policies,Economic Stabilization,Macroeconomic Management,Fiscal&Monetary Policy,Economic Theory&Research
Japan's official development assistance : recent issues and future directions
Japan remains the world's largest national donor of aid funds. But the Japanese government, facing prolonged economic stagnation and mounting public sector debt, is under increasing public pressure to reduce aid budgets and to use official development assistance in more explicit pursuit of Japan's own economic and political interests. Internationally, Japan continues to attract criticism for its emphasis on infrastructure projects and its limited willingness to participate in multilateral partnerships. The authors argue that Japan can meet these domestic and international challenges by developing a coherent national strategy for official development assistance, broadly designed to enhance effectiveness, accountability, and transparency.Decentralization,Banks&Banking Reform,Payment Systems&Infrastructure,Gender and Development,Economic Adjustment and Lending,Banks&Banking Reform,Development Economics&Aid Effectiveness,Economic Theory&Research,Economic Adjustment and Lending,Public Sector Economics&Finance
Coupling between pore formation and phase separation in charged lipid membranes
We investigated the effect of charge on the membrane morphology of giant
unilamellar vesicles (GUVs) composed of various mixtures containing charged
lipids. We observed the membrane morphologies by fluorescent and confocal laser
microscopy in lipid mixtures consisting of a neutral unsaturated lipid
[dioleoylphosphatidylcholine (DOPC)], a neutral saturated lipid
[dipalmitoylphosphatidylcholine (DPPC)], a charged unsaturated lipid
[dioleoylphosphatidylglycerol (DOPG)], a charged saturated
lipid [dipalmitoylphosphatidylglycerol (DPPG)], and
cholesterol (Chol). In binary mixtures of neutral DOPC/DPPC and charged
DOPC/DPPG, spherical vesicles were formed. On the other
hand, pore formation was often observed with GUVs consisting of
DOPG and DPPC. In a DPPC/DPPG/Chol
ternary mixture, pore-formed vesicles were also frequently observed. The
percentage of pore-formed vesicles increased with the DPPG
concentration. Moreover, when the head group charges of charged lipids were
screened by the addition of salt, pore-formed vesicles were suppressed in both
the binary and ternary charged lipid mixtures. We discuss the mechanisms of
pore formation in charged lipid mixtures and the relationship between phase
separation and the membrane morphology. Finally, we reproduce the results seen
in experimental systems by using coarse-grained molecular dynamics simulations.Comment: 34 pages, 10 figure
Charge-induced phase separation in lipid membranes
The phase separation in lipid bilayers that include negatively charged lipids
is examined experimentally. We observed phase-separated structures and
determined the membrane miscibility temperatures in several binary and ternary
lipid mixtures of unsaturated neutral lipid, dioleoylphosphatidylcholine
(DOPC), saturated neutral lipid, dipalmitoylphosphatidylcholine (DPPC),
unsaturated charged lipid, dioleoylphosphatidylglycerol
(DOPG), saturated charged lipid,
dipalmitoylphosphatidylglycerol (DPPG), and cholesterol.
In binary mixtures of saturated and unsaturated charged lipids, the combination
of the charged head with the saturation of hydrocarbon tail is a dominant
factor for the stability of membrane phase separation.
DPPG enhances phase separation, while
DOPG suppresses it. Furthermore, the addition of
DPPG to a binary mixture of DPPC/cholesterol induces phase
separation between DPPG-rich and cholesterol-rich phases.
This indicates that cholesterol localization depends strongly on the electric
charge on the hydrophilic head group rather than on the ordering of the
hydrocarbon tails. Finally, when DPPG was added to a
neutral ternary system of DOPC/DPPC/Cholesterol (a conventional model of
membrane rafts), a three-phase coexistence was produced. We conclude by
discussing some qualitative features of the phase behaviour in charged
membranes using a free energy approach.Comment: 17 pages, 6 figure
Frequency of Actual Mosquito Attacks during the Summer Season in Central Japan: a Monitored Investigation.
Weekly records of mosquito attacks in the usual life of voluntary monitors were analyzed to evaluate the realistic frequency of mosquito attacks. Culex pipiens pallens, Cx. tritaeniorhynchus, and Aedes albopictus were equally incriminatory species. The male monitors who engaged in outdoor activities such as cleaning, repairing and gardening experienced more attacks than the others whose main outdoor activities were shopping, strolling and visiting other places. More attacks were reported from June to August than in other months, and the number of attacks per man-day was consistently around 0.3 during this period, although the predominant species shifted from Cx. pipiens pallens to Cx. tritaeniothynchus and Ae. albopictus. The attacks were most frequent at dusk. Seasonal change in the density examined by UV-light trap did not always reflect the seasonal tendency of attacks
Lubrication effects on droplet manipulation by electrowetting-on-dielectric (EWOD)
Electrowetting has a potential to realize stand-alone point-of-care (POC)
devices. Here we report droplet-migration characteristics on oil-infused
electrowetting-on-dielectric (EWOD) substrates. We prepare sparse micropillars
to retain the oil layer in order to exploit the layer as a lubricating film. A
physical model of the droplet velocity is developed, and effects of the
lubrication, the oil viscosity, the droplet volume, and the thickness of solid
and liquid dielectric layers are discussed. It is found that the droplet
velocity is scaled as square of E, which differs from a relationship of cube of
E for droplets sliding down on liquid-infused surfaces by gravity. Furthermore,
our device achieves droplet velocity of 1 mm/s at the applied voltage of 15 V.
The velocity is approximately tenfold as high as the same condition (applied
voltage and oil viscosity) on porous-structure-based liquid-infused surfaces.
The achieved high velocity is explained by a lubrication-flow effect.Comment: 16 pages, 10 figure
In vitro heat effect on heterooligomeric subunit assembly of thermostable indolepyruvate ferredoxin oxidoreductase
AbstractIndolepyruvate ferredoxin oxidoreductase (IOR) from hyperthermophilic archaeon Pyrococcus kodakaraensis KOD1 catalyzes the oxidative decarboxylation of arylpyruvates by forming a heterooligomeric complex (α2β2). The genes iorA and iorB which encode respective α and β subunits, were coexpressed heterologously in Escherichia coli cells under anaerobic conditions. IOR activity was detected from the cell extract containing both subunits and its activity was enhanced by in vitro heat treatment prior to the assay. The iorA and iorB were expressed individually and each subunit was examined for enzymatic activity with and without heat treatment. IOR activity was detected neither from the extract of α subunit nor β subunit. The α and β subunits were mixed and then IOR activity was examined. Weak IOR activity was detected without heat treatment, however, upon heat treatment its activity was enhanced. The mixture of individually heat treated α and β subunits did not possess any IOR activity even though the mixed sample was heat treated again. IOR α and β subunits were individually purified to homogeneity, mixed with or without heat treatment and subunit assembly was examined by determining molecular mass. Upon heat treatment, inactive α and β were converted to an active high molecular weight complex (195 kDa) which corresponds to the α2β2 structure. However, the active complex was not formed without heat treatment, suggesting that high temperature environments are important for the hetero-oligomerization of IOR subunits
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