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INTRODUCTION A three-dose recombinant vaccine against hepatitis E, Hecolin, has been licensed for use in China since 2011. While not recommended for routine use due to lack of evidence on burden in the general population, in 2015 WHO recommended the vaccine be considered in outbreaks. As of early 2022 however, the vaccine had not been used in outbreak settings. A reduced-dose vaccination schedule, if effective, could make the vaccine an important outbreak response tool. In response to an increase in hepatitis E cases in a camp for internally displaced people in Bentiu, South Sudan in late 2021, MSF and South Sudan’s MoH implemented the first ever mass reactive vaccination campaign against hepatitis E virus (HEV). Three vaccination rounds took place in March, April, and October 2022, targeting 26,848 individuals aged 16-40 years, including pregnant women. We set up enhanced surveillance and conducted a case-control study to estimate two-dose vaccine effectiveness (VE). METHODS All suspected cases presenting to the MSF hospital who were eligible for vaccination and provided consent were enrolled in the study, comprising a questionnaire, laboratory examinations and a follow-up visit after 2-4 weeks. Vaccine-eligible suspect cases were matched to community controls. We estimated two dose VE against probable (anti-HEV IgM positive with elevated alanine transaminase, or a four-fold rise in IgG in paired samples) and confirmed (HEV RNA positive) hepatitis E using conditional logistic regression models. ETHICS This study was approved by the MSF and South Sudan Ethics Review Boards. RESULTS Considering the period two weeks after the second vaccination round between 11 May and 30 December 2022, 287 vaccine-eligible suspect hepatitis E cases were enrolled, including one probable and 16 confirmed cases. Among probable and confirmed cases, two (11.8%) were vaccinated with two or more doses compared to 40 (40%) of their 100 matched controls. We estimated a VE of 86.5% (95% confidence interval, CI, 36.3–97.1) for one/two doses and 83.9% (95% CI, -33.1–98.1%) for two doses. In addition to this direct protection, we observed a 5.5-fold decrease in the incidence rate of probable/confirmed cases hepatitis E cases before and after the second dose campaign (including those not eligible for vaccination). Laboratory confirmation of hepatitis E infection is ongoing, and we expect to revise VE estimates and incidence based on these results. CONCLUSION Following the first mass reactive vaccination campaign against hepatitis E, incidence has declined. Preliminary VE estimates suggest that the short-term protection provided by this reduced dose regimen may be high and potentially sufficient for outbreak response. CONFLICTS OF INTEREST None declared

Nature in Singapore, Supplement 1, 38-59

Background: Point-of-care ultrasound (PoCUS) can serve as a valuable adjunct for patient care. This study aimed to investigate the clinical integration of PoCUS of the first post-graduate year (PGY-1) residents after a PoCUS curriculum.Methods: The prospective study was conducted at the emergency department (ED) of the National Taiwan University Hospital between July 2015 and October 2017. Every PGY-1 resident had one-month ED training and a PoCUS curriculum was implemented during the first week. The post-training objective structured clinical examination global ratings were obtained, as well as the sonographic examinations the residents performed on shifts. Four groups could be identified: group 1 performed PoCUS before and after the curriculum; group 2 performed only after the curriculum; group 3 performed only before the curriculum; the last did not perform any examinations.Results: 239 residents participated. The median global rating was 4 (interquartile ranges, 4-5). After the curriculum, an increasing number of residents integrated PoCUS into patient care (64 vs. 170, p=0.037) with acceptable image quality. No differences existed in the global ratings between 4 groups, however, nearly 30% of residents did not use PoCUS during their shifts. Group 1 performed more cases with better image quality and using ≥2 US applications (8/100 vs. 82/359, p=0.0009), compared with those before the curriculum. Comparing with those in groups 1 and 2, group 1 performed more cases (pConclusions: A short focused US training had an immediate positive impact on OSCE global ratings and integration of PoCUS of PGY-1 residents in the ED. The global ratings could not predict whether to use PoCUS in the ED practice. Although the working climate was designated to be friendly for utilizing US, a substantial percentage of residents did not use PoCUS. Further longitudinal studies would be needed for the sustained effects of the curriculum.Trial registration: NCT03738033.

Allowing migration activity as an integral part of demographic transition and economic development, we establish a locational quantity-quality trade-off of children and explore its macroeconomic consequences. We construct a dynamic competitive migration equilibrium framework with rural agents heterogeneous in skills and fertility preferences. We then establish and characterize a mixed migration equilibrium where high-skilled rural agents with low fertility preferences always migrate to cities, low-skilled with high fertility preferences always stay, and only an endogenously determined fraction of high-skilled/high fertility preferences or low-skilled/low fertility preferences ends up moving. By calibrating our model to fit the data from China, we find interesting interactions between fertility and migration decisions in various counterfactual experiments with respect to changes in migration, population control and rural land entitlement policies. We conclude that overlooking the locational quantity-quality trade-off of children may lead to nonnegligible biases in assessing the implications and effectiveness of government policies.

This paper examines the instability property of balanced-budget taxation on factor income and consumption in a two-sector real business cycle model with home production. We show that the presence of home production, which is a nontaxed sector, reinforces the intratemporal and intertemporal substitution effects of balanced-budget rules. As a result, it strengthens the destabilization effect of factor income taxes and weakens the stabilization effect of consumption taxes. Moreover, our calibration shows that the number of OECD countries’ tax-rate combinations that fall into the instability region rises when home goods account for a larger share of aggregate consumption, and hence persistent cycles can easily occur following a fundamental shock or a sunspot shock.

In a real macroeconomic model, it is well established that a balanced-budget rule based on consumption tax can rule out indeterminacy. The present paper shows, both analytically and numerically, that such a balanced-budget rule induces indeterminacy and, hence, aggregate instability in a standard one-sector cash-in-advance economy. From a policy perspective, our results raise possible concerns that balanced-budget rules with endogenous consumption tax could have destabilizing effects under the current over-easy monetary environment.

While there is a renewed literature connecting internal migration to various issues related to structural transformation such as urban labor and housing markets, the relationship between internal migration and demographic transition is much under-studied despite its importance in the process of economic development. Our article fills this knowledge gap. By constructing a simple dynamic framework in which fertility and rural-urban migration decisions are both determined, we show that more-rapid urban productivity advancement can lead to a positive relationship between migration and fertility. Using cross-country data analysis, we support our theory, establishing that both migration and fertility rates are higher in less-developed countries than in advanced economies. Our results imply that policies that may help reduce the cost of urban living or enhance urban benefits would be useful for productive structural transformation.

This paper generalizes the theoretical model of Aghion et al. (2012) to re-examine the cyclicality of R&D investment with credit constraint and linear production with different innovation capabilities. In contrast to their procyclical conclusion, we show that the R&D investment can be acyclical, procyclical, or countercyclical depending on the innovation capability, the tightness of credit constraint and the level of an entrepreneur‘s wealth.

Nature in Singapore, 12, 15-36

Income disparity across countries has been large and widening over time. We develop a tractable model where factor requirements in production technology do not necessarily match a country's factor input profile. Appropriate assimilation of frontier technologies balances such multi-dimensional factor input-technology mismatch, thus mitigating the efficiency loss. This yields a new measure for endogenous TFP, entailing a novel trade-off between a country's income level and income growth that depends critically on the assimilation ability and the factor input mismatch. Our baseline model accounts for 80%-92% of the global income variation over the past 50 years. The widening of mismatch and heterogeneity in the assimilation ability account for 41% and 20% of the global growth variation, whereas physical capital accounts for about one third with human capital largely inconsequential. In particular, about 30% of the output growth in miracle Asian economies comes from narrowing the gap arisen from mismatch, and 94% of the growth stagnation in trapped African economies due to the widening mismatch. A country may fall into a middle-income trap after a factor advantage reversal that changes the pattern of mismatch.

Why have the income disparities between fast-growing economies and development laggards widened over the past five decades? How important is the role played by institutional barriers with relation to technology adoption? Using cross-country analysis, we find that more-severe institutional barriers in several representative lag-behind countries actually hinder the process of structural transformation and economic development, causing these countries to fall below a representative group of fast-growing economies despite having similar or even better initial states five decades ago. We also find that institutional barriers have played the most important role, accounting for more than half the economic growth in fast-growing and trapped economies and for more than 100 percent of the economic growth in the lag-behind countries. By conducting country studies, we identify that unnecessary protectionism, government misallocation, corruption, and financial instability have been key institutional barriers causing countries to either fall into the poverty trap or lag behind without a sustainable growth engine.

This paper examines the relation between factor substitution and (local) stability of equilibria in a one-sector real business cycle model under balanced-budget rules. We show that under non-unitary elasticity of factor substitution, the Schmitt-Grohe-Uribe indeterminacy result can be altered. Using the two-step normalization procedure, we highlight two opposing effects of factor substitution, namely, the efficiency effect and the distribution effect, on aggregate stability. With endogenous distortionary taxes and gross substitutability between capital and labor, the existing literature overlooks the distribution effect and finds that balanced-budget rules are likely to deliver indeterminacy. However, if capital stock is relatively more abundant, a higher elasticity of substitution generates a source of stability due to the distribution effect. Our calibration shows that the distribution effect is always the dominating force.

We develop an overlapping-generations framework of education-based migration that takes place prior to labor-market participation and explore its role for economic development, urbanization and workforce composition. We show that education-based and work-based migration are substitutes and the equilibrium outcome depends crucially on children’s talent distribution, college costs and selectiveness, urban job opportunities, and migration barriers. We establish conflicting partial- and general-equilibrium effects at work for comparative statics, and examine their locational as well as macroeconomic implications for assessing education and migration policies. Applying our model to fit the data from China over 1980–2007, we find that, although education-based migration only amounts to one-fifth of that of work-based migration, it contributes more to per capita output growth than work-based migration owing to its high-skilled nature. Moreover, the abolishment of education-based migration policy and the relaxation of the work-based migration are found to have limited effects on per capita output and urbanization.

To explore the interplays between trade and institutions, we construct a staged development framework with multi-period discrete choices to study the colonization of Hong Kong, which served to facilitate the trade of several agricultural and manufactured products, including opium, between Britain and China. Based on the historical data and documents that we collected from limited sources, we design our dynamic trade model to capture several key features of the colonization process and use it to characterize the endogenous transition from the pre-Opium War era, to the post-Opium War era and then to the post-opium trade era, which span the period 1773-1933. We show that while the low opium trading cost and the high warfare cost initially postponed any military action, the high valuation of the total volume of bilateral trade, the rising opium trading cost and the anticipated increase in the demand for opium eventually led the British government to declare the Opium Wars, legalizing opium trade via the colonial Hong Kong. We also show that, in response to a drastic drop in opium demand and a rising opium trading cost, it became optimal for the British government to abandon opium trade soon after the founding of the Republic of China.

In this paper, we examine the effects of constant-rate factor taxation on macroeconomic stability in the Woodford (1986) model. Our focus is on how the degree of factor substitution, as measured by the elasticity of factor substitution (EOS) in production, affects different balanced-budget tax rules. Analytically, we show that indeterminacy can occur under capital income taxation only when the EOS is very low, whereas indeterminacy under labor income taxation is not subject to the EOS restriction. This finding is robust when we tax all of the factor incomes with equal rates. Thus, in terms of macroeconomic stability, taxing capital income is preferred to taxing labor income.

This paper examines the relation between aggregate elasticity of substitution (AES) and capital accumulation (the AES-K relation) in a general multi-sector Solow growth model with all CES production technologies. There are two intermediate goods produced by capital and labor, while the final good is produced by combining the two intermediate goods. When capital is sector-specific, then it is found that a positive AES-K relation emerges ony if the elasticity of substitution (ES) between capital and labor is of the same sign as the ES between the inter-mediate goods, but with the latter having a larger magnitude as required by the restriction of capital-skill complementarity. We also introduce the concepts of "global" versus "local" AES-capital relation and highlight that the AES findings of the existing literature are local ones. The general conclusion of our analysis is that capital mobility is an important factor for the likelihood of a positive AES-K relation.

This paper provides a unified approach to characterizing the relation between factor substitution and economic growth in different one-sector growth models (namely, the Solow, Ramsey, and Diamond models). Our main finding is that if better factor substitution raises savings in the steady state, then a higher per capita income results. There are two channels by which factor substitution affects savings: the positive efficiency effect via income and the ambiguous distribution effect via factor income shares. If the efficiency effect dominates, then a higher elasticity of substitution leads to a higher level of per capita steady-state income. In transition, factor substitution affects the rate of convergence both directly and through the equilibrium profit share. The former arises from diminishing marginal productivity of capital whereas the latter reflects its relative scarcity. Depending on the interaction of these effects, the net outcomes are characterized.

Many of the genes and enzymes critical for assembly and biogenesis of yeast cell walls remain unidentified or poorly characterized. Therefore, we designed a high throughput genomic screen for defects in anchoring of GPI-cell wall proteins (GPI-CWPs), based on quantification of a secreted GFP-Sag1p fusion protein. Saccharomyces cerevisiae diploid deletion strains were transformed with a plasmid expressing the fusion protein under a GPD promoter, then GFP fluorescence was determined in culture supernatants after mid-exponential growth. Variability in the amount of fluorescent marker secreted into the medium was reduced by growth at 18 degrees C in buffered defined medium in the presence of sorbitol. Secondary screens included immunoblotting for GFP, fluorescence emission spectra, cell surface fluorescence, and cell integrity. Of 167 mutants deleted for genes affecting cell wall biogenesis or structure, eight showed consistent hyper-secretion of GFP relative to parental strain BY4743: tdh3 (glyceraldehyde-3-phosphate dehydrogenase), gda1 (guanosine diphosphatase), gpi13 and mcd4 (both ethanolamine phosphate-GPI-transferases), kre5 and kre1 (involved in synthesis of beta1,6 glucan), dcw1(implicated in GPI-CWP cross-linking to cell wall glucan), and cwp1 (a major cell wall protein). In addition, deletion of a number of genes caused decreased secretion of GFP. These results elucidate specific roles for specific genes in cell wall biogenesis, including differentiating among paralogous genes.

This paper examines the effects of illegal immigration in a neoclassical growth model with two groups of workers, skilled and unskilled. We show that although illegal immigration is a boon to a country as a whole, there are distributional effects, whose sign is in general ambiguous. This is because all sources of income of both groups are affected and some of these changes tend to move income in opposite directions. Nevertheless, calibration exercises show that the wealth distribution is likely to become more unequal as the number of illegal immigrants increases. We confirm most of our calibration results analytically in a small open economy version of the basic model. Finally, our results remain robust when we extend the model to allow for endogenous skill acquisition.

This paper introduces a new production externality via factor substitution and explores its effects on generating indeterminacy in one-sector growth models. With the elasticity of substitution depends on the average level of capital intensity, indeterminacy is possible as long as the steady-state level of capital is below the normalized level of the CES production function. Given that the elasticity of factor substitution is decreasing in capital and the marginal product of capital is decreasing in terms of the elasticity, indeterminacy can occur because efficient factor substitution from capital deepening offsets the diminishing returns of capital.

Primary issues for the fluidized-bed/transport reactor process are high attrition resistant sorbent, its high sorption capacity and regenerability, durability, and cost. The overall objective of this project is the development of a superior attrition resistant zinc oxide-based sorbent for hot gas cleanup in integrated coal gasification combined cycle (IGCC). Sorbents applicable to a fluidized-bed hot gas desulfurization process must have a high attrition resistance to withstand the fast solid circulation between a desulfurizer and a regenerator, fast kinetic reactions, and high sulfur sorption capacity. The oxidative regeneration of zinc-based sorbent usually initiated at greater than 600 C with highly exothermic nature causing deactivation of sorbent as well as complication of sulfidation process by side reaction. Focusing on solving the sorbent attrition and regenerability of zinc oxide-based sorbent, we have adapted multi-binder matrices and direct incorporation of regeneration promoter. The sorbent forming was done with a spray drying technique that is easily scalable to commercial quantity.

Dry regenerable sorbent technology is one of the emerging technologies as a cost-effective and energy-efficient technology for CO2 capture from flue gas. Six sodium-based dry regenerable sorbents were prepared by spray-drying techniques. Their physical properties and reactivities were tested to evaluate their applicability to a fluidized-bed or fast transport-bed CO2 capture process. Each sorbents contained 20−50 wt% of Na2CO3 or NaHCO3. All sorbents except for Sorb NX30 were insufficient with either attrition resistance or reactivity, or both properties. Sorb NX30 sorbent satisfied most of the physical requirements for a commercial fluidized-bed reactor process along with good chemical reactivity. Sorb NX30 sorbent had a spherical shape, an average size of 89 μm, a size distribution of 38−250 μm, and a bulk density of approximately 0.87 g/mL. The attrition index (AI) of Sorb NX30 reached below 5% compared to about 20% for commercial fluidized catalytic cracking (FCC) catalysts. CO2 sorption capacity of S...

By relaxing the restrictions commonly imposed on the magnitude of capital externalities in one-sector models with Cobb–Douglas technology, we find that indeterminacy can arise in the following two cases: (i) the felicity function is separable in consumption and leisure and there are negative capital externalities; (ii) the felicity function is non-separable and the social elasticity of production with respect to capital is greater than one. In both cases indeterminacy happens when the aggregate labor-demand curve is downward-sloping. In addition, with Cobb–Douglas technology we show that the presence of income effects on the demand for leisure is a necessary condition for indeterminacy to occur, and that therefore for certain felicity functions characterized by the presence of no income effects indeterminacy can never occur regardless of the signs and magnitudes of capital and labor externalities.

Highly reactive and attrition-resistant ZnO-based sorbents that are suitable for bubbling fluidized-bed reactors can be produced using the spray-drying method. Most of the ZnO-based sorbents prepared here (ZAC-X, X = 18N−25N) satisfy the physical and chemical criteria for bubbling fluidized-bed application [spherical shape, average particle size, 90−110 µm; size distribution, 40−230 µm; bulk density, 0.9−1.0 g/mL; attrition index (AI), 40−80%; sulfur sorption capacity, 14−17 wt %; sorbent use, 70−80%]. The performance test of the ZAC-C sorbent at Korea Institute of Energy Research (KIER) with a bubbling fluidized-bed for 70 h also demonstrated that it had good sulfidation and regeneration performance (11 wt % sorption capacity and 52% sorbent use) as well as reasonable attrition resistance (1.1% attrition loss for 70 h).

The effects of a compatibilizer on polypropylene (PP)/poly(acrylonitrile-butadiene-styrene) (ABS) blends were studied. Blends of the PP/ABS, with PP-g-SAN copolymer as a compatibilizer, were prepared using a twin screw extruder. The flexural and impact strength of the PP/ABS blends with the PP-g-SAN copolymer increased significantly with PP-rich compositions on the addition of the PP-g-SAN copolymer at 3 phr. The increase in the mechanical properties of the PP/ABS/PP-g-SAN blend may have been due to the toughening effects of the ABS in the PP-rich compositions. In the morphology study of the PP/ABS/PP-g-SAN (80/20) blend with the PP-g-SAN copolymer, the minimum droplet size, 5.1 μm, was observed with the addition of 3 phr of the PP-g-SAN copolymer. The complex viscosity of the PP/ABS/PP-g-SAN (80/20) blends increased with the addition of 3 phr of the PPg-SAN copolymer. From the above mechanical properties, morphology and complex viscosity results for the PP/ ABS blends, it is suggested that the compatibility is more increased with the PP-rich composition (PP:ABS = 80/ 20 wt%) of the PP/ABS blend on the addition of 3 phr of the PP-g-SAN copolymer.

In this paper, the first demonstration of a novel-concept for an ultra-high density and low-cost, non-solder based interconnection technology, which can be applied for miniaturized board-to-board (BTB) as well as 2nd level package-to-system board interconnections, is reported. This is an array type, dry-fit interconnection technology that is modeled, simulated, designed and fabricated. Such a technology is expected to have many applications in small consumer systems such as smart mobile and wearable electronics. This paper presents three key innovations. The first innovation is the introduction of non-solder based, dry-fit interconnection concept. The second innovation is the demonstration of the reduced interconnection height of 0.45 mm, compared to a typical 0.7∼1.0 mm mating height in most miniaturized BTB connectors in the market [1]. This thin mating height is one of the important features in portable electronics applications [2]. The third innovation is in the manufacturing processes. Unlike conventional BTB connectors, simplified and standard manufacturing processes were applied to build this innovative interconnection structure.

This paper reexamines the welfare effects of illegal immigration studied by Hazari and Sgro [The simple analytics of optimal growth with illegal migrants. Journal of Economic Dynamics and Control 28(1) 141–151]. In contrast to their negative conclusion, we obtain ambiguous welfare prediction which is due to the presence of two opposing effects at work: a positive exploitation effect and a negative intertemporal effect. With Cobb–Douglas production technology, we show that per capita domestic consumption rises in the presence of illegal migration.

This study explores the possibility of controlling the temperature coefficient of capacitance (TCC) of a nanocomposite capacitor with nano-sized BaTiO 3 of positive TCC as ceramic filler and bisbenzocyclobutene of negative TCC as polymer matrix. The nanocomposite could be tailored to modulate its TCC from positive over zero to negative values.

We analyze the gains from trade for a small cash-in-advance economy with endogenous labor supply and learning-by-doing in the accumulation of human capital. Contrary to previous findings, we show that free trade is not optimal independently of the relative amount of cash required for the purchase of each good. Furthermore, a monetary rule a la Friedman can eliminate distortions deriving from the cash-in-advance constraint only under segmented financial markets; in any case, it cannot restore the economic optimum. Finally, we identify government intervention policies, such as wage and export subsidies, that can be welfare improving.

In this paper, we explore the possibility of having money as a source of indeterminacy in endogenous growth models. We adopt the simple Ak model of endogenous growth to be the main analytical vehicle whose balanced growth paths do not display local indeterminacy. Money is introduced via either a general cash-in-advance (CIA) constraint or a pecuniary transactions costs (PTC) technology. It is shown that local indeterminacy of the dynamics is due to the presence of an intertemporal substitution effect on capital accumulation that works against and dominates the conventional inflation effect of Tobin [1965, Money and economical growth. Econometrica 33(4), Part 2, 671]. If money is growth-rate superneutral, then the intertemporal substitution effect is absent so that local indeterminacy cannot occur. Finally, the strength of the intertemporal substitution effect depends positively on the intertemporal elasticity of substitution in consumption.

By adding endogenous investment to a flexible-price, money-in-the-utility-function model, this paper studies the role that physical capital plays in stabilizing the real side of the economy when the monetary authority follows interest-rate feedback rules. We show that with inelastic labor supply equilibrium uniqueness is ensured under both active and passive monetary policies. For the case where money affects both preferences and technology, the uniqueness result remains true under active monetary policy. With endogenous labor supply, the uniqueness result holds again regardless of the stance of monetary policies for the case with separable leisure, but indeterminacy remains likely under both active and passive monetary policies when leisure is nonseparable.

The authors analyze an endogenous growth model with economy-wide increasing returns, in which a public input is essential for private production. Within such a framework, it is shown that a continuum of equilibria and global indeterminacy can arise for reasonable parameter values, simply due to the presence of endogenous public policy. This can potentially account for “leapfrogging” or retroceding growth experiences. It is demonstrated how fiscal policy can serve as a selection device among different convergent paths.

Credit rationing is a common feature of most developing economies. In response to it, the governments of these countries often operate a number of programs intended to expand the supply of credit to the private sector. Expansionary monetary policy is often seen as a way of reducing the extent of credit rationing. We examine the consequences of a common policy tool in these economies: the use of expansionary monetary policy combined with direct central bank lending to inject credit. In the context of a small open economy we show that such a policy increases long-run production if and only if the economy is in a development trap. Moreover government credit programs often lead to endogenously arising aggregate volatility. Thus the case for government intervention in credit markets relies largely on the notion that output is artificially low because the economy is in a development trap. However, it is the case that the kind of policy we consider can be used to eliminate certain indeterminacies of equilibrium created by endogenous credit market frictions. Journal of Economic Literature Classification Numbers: E44, O16, O42.

A 23-year-old man with a history of limited right ankle dorsiflexion presented to the MRI suite for a routine lumbar spine MRI. The patient denied history of prior spinal trauma or systemic symptoms. Aside from mild right ankle pain, physical and neurological examinations were unremarkable. Lumbar spine MRI revealed subdural fluid collections at T12-S1 levels (figure 1A, B). Follow-up enhanced brain MRI (not shown) and cervicothoracic spine MRI (not shown) in the same week were both unremarkable, with no evidence of intracranial hypotension or extra-arachnoid fluid collections. Two weeks later, CT myelogram (figure …

We examine the welfare effects of a customs union on a small monetary economy. The role of money is captured by a generalized cash-in-advance constraint which allows for non-uniform monetization across sectors. This generates a demand-side distortion which results in a discrepancy between the marginal domestic rate of substitution and the world price. We show that, depending on the economy’s inflation rate and the difference between the existing and the optimal tariff rate, trade creation may reduce welfare while trade diversion may improve it.

This paper develops a standard trade model of a small open monetary economy with two traded and one non-traded goods. Money is introduced through a generalized cash-in-advance constraint where the share of goods purchases that must be made using cash, varies across sectors. We find that free trade may be harmful so that alternative policy instruments may be considered to improve welfare. In addition, we study and compare the optimal tariff formula and the optimal consumption tax structure. In the presence of a monetary distortion of the non-traded good, a consumption tax may not Pareto dominate a tariff although the latter bears an additional production burden. This corroborates the theory of second best.

This paper builds a two-country intertemporal macroeconomic model similar to one developed recently by Obstfeld and Rogoff. Imperfectly competitive producer/consumers maximize an intertemporal utility function with consumption, real money balances and output as arguments. We use the framework to examine both the short-run and steady-state effects of the imposition of a tariff in one of the countries. This results in a fall in the tariff imposer's output in both the steady state and in the short run. A small tariff may make a country worse off (contrary to the usual result under perfect competition). Spillover effects are also considered.

This paper examines the welfare effects of commercial and tax/subsidy policies on a developing economy with sectoral unemployment and differential cash-in-advance constraints. The optimal tariff can be negative when the cash-in-advance requirement for buying the importable good is larger than that for the exportable good. In addition, when capital is sectorally mobile, production taxes are superior to production subsidies to the importable sector. Nevertheless, to reach the first-best optimum, a uniform wage subsidy to both sectors is required.

This paper analyzes the relationship between economic growth, industrialization, and international trade in a two-sector endogenous growth model. With learning-by-doing, the economy grows perpetually along a balanced growth path, with manufacturing’s relative price declining continuously. Under trade, its pattern of trade and growth will be affected by external growth. If it remains diversified under trade, its growth can keep in pace with the rest of the world. If the growth rate of the rest of the world is higher than a certain limit, the economy cannot catch up and will eventually produce agriculture only.

This paper constructs a two-sector overlapping-generations model of endogenous growth to study the effects of brain drain on growth, education and income distribution. It is shown that brain drain reduces the economic growth rate and generally hurts the non-emigrants through the static income-distributional effects and the dynamic damage on economic growth and human capital accumulation. If the initial rate of human capital accumulation is relatively low, brain drain could deteriorate both the sum of discounted income and lifetime discounted utility of a representative non-emigrant. The government can choose to spend more on education to lessen the detrimental growth effects of brain drain.

The rate of formation of spheroplasts of yeast can be used as an assay to study the structural integrity of cell walls. Lysis can be measured spectrophotometrically in hypotonic solution in the presence of Zymolyase, a mixture of cell wall-digesting enzymes. The optical density of the cell suspension decreases as the cells lyse. We optimized this assay with respect to enzyme concentration, temperature, pH, and growth conditions for several strains of Saccharomyces cerevisiae. The level of variability (standard deviation) was 1–5% between trials where the replications were performed on the same culture using enzyme prepared from the same lot, and 5–15% for different cultures of the same strain. This assay can quantitate differences in cell wall structure (1) between exponentially growing and stationary phase cells, (2) among different S. cerevisiae strains, (3) between S. cerevisiae and Candida albicans, (4) between parental and mutated lines, and (5) between drug- or chemically-treated cells and controls. © 1998 John Wiley & Sons, Ltd.

A 38-year-old man presented with 2 to 3 months of intermittent headaches. Aside from hypertension, the patient was in good health. Physical examination and laboratory values were unremarkable. Routine unenhanced head CT (figure 1A,B) and gadolinium enhanced brain MRI (figure 2A–D) revealed a right frontoparietal cystic mass measuring 6.0×3.9×5.0 cm with an enhancing mural nodule and minimal peritumoral oedema. Imaging findings were suggestive of a primary glial tumour. The patient underwent surgery and the mass was completely resected. Histopathology …

This study examined the field precision of National Institute for Occupational Safety and Health (NIOSH) Method 3500, also known as chromotropic acid method, in the range of exposure limit covers the Occupational Safety and Health Administration (OSHA) permissible exposure limit of 0.75 ppm and the OSHA action level of 0.5 ppm airborne formaldehyde. Using this method, 78 area samples (25 sets of replicate samples) were collected in a workplace and analyzed. The concentrations of formaldehyde ranged from 0.05 to 1.72 ppm with a mean +/- standard deviation of 0.95 +/- 0.31 ppm. The precision (coefficient of variation, CV) of 25 sets of replicated samples ranged from 0.03 to 0.24 with an overall (pooled) precision of 0.09, which is in agreement with that stated in NIOSH Method 3500. In 68% of replicate samples the precision was equal to or less than 0.09. The relative accuracy of the sampling and analytical procedure used in this study was evaluated by collecting 12 sets of side-by-side replicate samples using both NIOSH Method 3500 and OSHA Method 5.2 Method 53 was used to determine whether the concentrations of formaldehyde were within the desired range. The overall mean concentrations were 0.98 +/- 0.42 for Method 3500 and 0.78 +/- 0.28 ppm for Method 5.2. These were no statistically different. The pooled CVs were 0.114 and 0.076 for Method 3500 and Method 52, respectively.

Within the one-sector optimal growth framework with public services and labour-leisure choice, we find that the effects of temporary productive government spending on the real interest rate depend on the discrepancy between actual and optimal government sizes as well as on the length of the action lag. This paper thus sheds light on the controversy between the empirical findings and the theoretical predictions regarding the behaviour of the real interest rate within the neoclassical framework.

We examine a two-sector endogenous growth model with general constant-return-to-scale production technologies governing the evolution of human and physical capital. We prove the existence, uniqueness, and saddle-path stability of the balanced growth equilibrium. A dual approach drawing on techniques from international trade theory is used to provide complete characterization of the transitional dynamics of consumption, goods and education outputs, human and physical capital inputs, and the relative price of human capital investment. We investigate the long-run effects of changes in time preference and factor taxation, and show the emergence of instability or indeterminacy when factor taxes are too distortionary.Journal of Economic LiteratureClassification Number: D90.

This study measures industrial output, employment and air pollution effects through the use of CNG in motor vehicles by utilizing the Pollution-Related Multiregional Household-Interactive Variable Input-Output (PHVIO) model. The impact analyses are conducted with three consecutive year scenarios of different level of CNG conversion of motor fleet vehicles for the target year, 1991, 1992, and 1993. The use of CNG in bus and truck vehicles of private businesses, consumers, and state and local governments produces the ‘substitution’ effect and ‘income’ effect. The use of CNG reduces the costs of transportation, and the output, employment and air pollution effects of the reduced transportation costs are referred as the substitution effect. The use of CNG increases natural gas consumption and requires CNG duel engine installation while it decrease gasoline consumption. The output, employment and air pollution effects of this final demand change are referred to the income effect. The industrial output and employment effects are measured in Oklahoma and the Rest of the U.S. Then Oklahoma State industrial and employment effects are divided into Oklahoma SMSA, Tulsa SMSA and the Rest of Oklakoma. Finally, the stationary source air pollution due to industrial effects and mobiles source air pollution due to CNG using motor vehicles are measured in Oklahoma SMSA and Tulsa SMSA.

The authors consider fiscal policy in an imperfectly competitive macroeconomy where money is nonneutral; an assumption of nominally rigid unemployment benefit is used to generate the nonneutrality. Wages are set by maximizing trade unions. Although expansionary monetary policy does raise output and welfare in such a framework, the government expenditure multiplier is always less than unity and may be negative. Welfare may decline even if an expansion of government spending raises output and employment. Copyright 1995 by Blackwell Publishers Ltd and The Victoria University of Manchester

The pharmacokinetics and tissue distribution of M1-M4 were compared after intravenous (i.v.) administration of DA-125, 25 mg kg-1, to BDF1 mice (n = 5 at each sampling time) and subcutaneously implanted Lewis-lung-carcinoma-bearing BDF1 mice (n = 10 at each sampling time. The mean plasma concentrations of M1-M4 were not significantly different between the two groups of mice, and hence similar pharmacokinetic parameters for M1-M4 were obtained. The amount of M1 in the lung was significantly greater in the tumour-bearing mice than in the control mice, resulting in a greater AUAt in the tumour-bearing mice (18,600 against 8940 micrograms min g-1), and vice versa in the liver (962 against 3840 micrograms min g-1). However, the corresponding values for other tissues were comparable between the control and tumour-bearing mice. The amount of M1 was greatest in the lung for up to 2 h in the tumour-bearing mice. M2 was the predominant metabolite among M1-M4 excreted in 24 h urine by both groups of mice; 8.36 and 10.7% of the i.v. dose were excreted in 24 h urine as M2--expressed in terms of DA-125--by the control and tumour-bearing mice, respectively. The amount of M1 in the tumour mass reached a mean Cmax of 3.75 micrograms g-1 immediately after i.v. administration of DA-125 to the tumour-bearing mice, then declined very slowly to an amount that remained almost constant for up to 24 h. This suggested that M1 has high affinity for the subcutaneously implanted Lewis lung carcinoma. The antitumour activity, such as the increase in life span (ILS) and tumour growth inhibition (TGI) of DA-125, 6-48 mg kg-1, and adriamycin (ADM), 3-18 mg kg-1, were also compared in subcutaneously implanted Lewis-lung-carcinoma-bearing BDF1 mice after four weekly i.v. administration of the drugs on days 1,8,15, and 22 following tumour implantation. More than three out of six mice survived as tumour-free for longer than 70 d at a DA-125 dose range of 6-24 mg kg-1, but there were no tumour-free mice at any dose of ADM. Assuming ILS values higher than 30% to be effective, DA-125 doses ranging from 6 to 24 mg kg-1 were effective in increasing the life span, which ADM does only within the dose range of 6-12 mg kg-1.