410 research outputs found

    Structural adjustment, economic performance, and aid dependency in Tanzania

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    Tanzania embarked on a structural adjustment program in 1986 after a decade of protracted economic decline. Its program was supported by the International Monetary Fund and the World Bank and was accompanied by a substantial increase in foreign assistance. After seven years of adjustment the environment for higher economic growth has improved, but the results are only partially encouraging: economic growth has only slightly exceeded population growth, and officially measured domestic savings have deteriorated. Meanwhile, Tanzania's dependency on foreign assistance has increased, reflected in a deterioration of the current account of the balance of payments. This has led to an increasingly heated debate about whether real adjustment is in fact taking place in Tanzania, or whether foreign aid has served to postpone adjustment instead of supporting it. The authors shed light on the relationship between adjustment and aid dependency on the basis of Tanzania's experience. Tanzania's weak database is adjusted in several respects to correct for the most glaring deficiencies in it. After adjustment of the database, Tanzania's performance is compared in the period 1981-85, prior to when reforms were launched, with that in the period 1986-90, which followed the launch of the Economic Recovery Program in 1986. To put the Tanzanian experience in context, its performance is also compared with that of four sub-Saharan African countries - Ghana, Kenya, Malawi, and Uganda - which embarked on similar reform programs during the 1980s. The adjustment of the macroeconomic data shows that, contrary to traditional interpretation, Tanzania's increased dependency of foreign assistance did not lead to a deterioration in domestic savings performance. Most of the foreign assistance was used for investment rather than for consumption. But the principal difference between Tanzania and the four sub-Saharan African countries sampled was the efficiency with which the foreign assistance was used. Using a measure of macroeconomic return on investment, the comparison shows that Tanzania is getting very little return on domestic investment even after the introduction of structural reforms. There are several reasons for this, including the dominance of the Tanzania economy by a large and highly inefficient parastatal sector. If Tanzania is to generate the accelerated growth that it so urgently needs, one of the key areas of policy reform needs to be the increase in productivity of domestic investment.ICT Policy and Strategies,Economic Theory&Research,Achieving Shared Growth,Environmental Economics&Policies,Economic Stabilization

    New Nonthermal Filaments at the Galactic Center: Are They Tracing a Globally Ordered Magnetic Field?

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    New high-resolution, wide-field 90 cm VLA observations of the Galactic center (GC) region by Nord and coworkers have revealed 20 nonthermal filament (NTF) candidates. We report 6 cm polarization observations of six of these. All of the candidates have the expected NTF morphology, and two show extended polarization, confirming their identification as NTFs. One of the new NTFs appears to be part of a system of NTFs located in the Sgr B region, 64 pc in projection north of Sgr A. These filaments cross the Galactic plane with an orientation similar to the filaments in the Galactic center radio arc. They extend the scale over which the NTF phenomena is known to occur to almost 300 pc along the Galactic plane. Another NTF was found in the Galactic plane south of the Sgr C filament but with an orientation of 45° to the Galactic plane. This is only the second of 12 confirmed NTFs that is not oriented perpendicular to the Galactic plane. An additional candidate in the Sgr C region was resolved into multiple filamentary structures. Polarization was detected only at the brightness peak of one of the filaments. Several of these filaments run parallel to the Galactic plane and can be considered additional evidence for nonpoloidal magnetic fields at the GC. Together the 90 and 6 cm observations indicate that the GC magnetic field may be more complex than a simple globally ordered dipolar field

    The social value of a QALY : raising the bar or barring the raise?

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    Background: Since the inception of the National Institute for Health and Clinical Excellence (NICE) in England, there have been questions about the empirical basis for the cost-per-QALY threshold used by NICE and whether QALYs gained by different beneficiaries of health care should be weighted equally. The Social Value of a QALY (SVQ) project, reported in this paper, was commissioned to address these two questions. The results of SVQ were released during a time of considerable debate about the NICE threshold, and authors with differing perspectives have drawn on the SVQ results to support their cases. As these discussions continue, and given the selective use of results by those involved, it is important, therefore, not only to present a summary overview of SVQ, but also for those who conducted the research to contribute to the debate as to its implications for NICE. Discussion: The issue of the threshold was addressed in two ways: first, by combining, via a set of models, the current UK Value of a Prevented Fatality (used in transport policy) with data on fatality age, life expectancy and age-related quality of life; and, second, via a survey designed to test the feasibility of combining respondents’ answers to willingness to pay and health state utility questions to arrive at values of a QALY. Modelling resulted in values of £10,000-£70,000 per QALY. Via survey research, most methods of aggregating the data resulted in values of a QALY of £18,000-£40,000, although others resulted in implausibly high values. An additional survey, addressing the issue of weighting QALYs, used two methods, one indicating that QALYs should not be weighted and the other that greater weight could be given to QALYs gained by some groups. Summary: Although we conducted only a feasibility study and a modelling exercise, neither present compelling evidence for moving the NICE threshold up or down. Some preliminary evidence would indicate it could be moved up for some types of QALY and down for others. While many members of the public appear to be open to the possibility of using somewhat different QALY weights for different groups of beneficiaries, we do not yet have any secure evidence base for introducing such a system

    The Galactic Center Nonthermal Filaments: Recent Observations and Theory

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    The large-scale topology and strength of the Galactic Center magnetic field have been inferred from radio imaging of the nonthermal filaments (NTFs). These objects, which seem to be unique to the Galactic center, are defined by extreme aspect ratios and a high degree of polarization. Recent high resolution, wide-field VLA imaging of the GC at 90 cm has revealed new candidate NTFs with a wide range of orientations relative to the Galactic plane. We present follow up 6 cm polarization observations of 6 of these candidates and confirm 4 as new NTFs. Together the new 90 and 6 cm results complicate the previous picture of largely perpendicular filaments that trace a globally ordered magnetic field. NTF observations in general do not rule out any particular models for the origin of the NTFs. Hence we explore the idea that the NTFs are local, individual structures: magnetic wakes generated through the interaction of molecular clouds with a Galactic Center wind. Numerical simulations of the evolution of a magnetized wake will be discussed and compared with NTF observations

    Evidence of a Weak Galactic Center Magnetic Field from Diffuse Low-Frequency Nonthermal Radio Emission

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    New low-frequency 74 and 330 MHz observations of the Galactic center (GC) region reveal the presence of a large-scale (6° × 2°) diffuse source of nonthermal synchrotron emission. A minimum-energy analysis of this emission yields a total energy of ~(phi4/7f3/7) × 1052 ergs and a magnetic field strength of ~6(phi/f)2/7 μG (where phi is the proton to electron energy ratio and f is the filling factor of the synchrotron emitting gas). The equipartition particle energy density is 1.2(phi/f)2/7 eV cm-3, a value consistent with cosmic-ray data. However, the derived magnetic field is several orders of magnitude below the 1 mG field commonly invoked for the GC. With this field the source can be maintained with the supernova rate inferred from the GC star formation. Furthermore, a strong magnetic field implies an abnormally low GC cosmic-ray energy density. We conclude that the mean magnetic field in the GC region must be weak, of order 10 μG (at least on size scales gtrsim125\u27\u27)
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