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We describe the clinical features and treatment outcome of a patient with combined central retinal vein occlusion and cilioretinal artery occlusion. A 52-year-old female presented to our clinic with decreased vision in the right eye for 4 days. Visual acuity and intraocular pressure were count fingers at 2&1/2M and 14 mm Hg in the right and 20/20 and 16 mm Hg in the left eye, respectively. Funduscopic exam and optical coherence tomography (OCT) of the right eye confirmed the diagnosis of concurrent cilioretinal artery occlusion and central retinal vein occlusion with segmental macular pallor in the territory of the cilioretinal artery, corresponding marked inner retina thickening on OCT and signs of vein occlusion. The patient received an intravitreal injection of bevacizumab and at 1-month follow-up, vision improved to 20/30 with corresponding anatomical improvement. It is very important to recognize combined central retinal vein occlusion and cilioretinal artery occlusion as they could be treated with intravitreal injections of anti-vascular endothelial growth factors with favorable treatment outcomes.

We report the case of a 35-year-old female with combined Chiari 1 malformation and basilar invagination, who presented with intermittent conjunctival chemosis and unilateral chorioretinal folds that were temporally correlated. She denied any flashes, floaters, eye redness, or pain. She also denied nausea or vomiting. Clinical exam and optical coherence tomography imaging revealed conjunctival chemosis and chorioretinal folds in the left eye. Subsequent magnetic resonance imaging of the brain and the orbits were consistent with combined Chiari 1 malformation and basilar invagination. The unilateral and intermittent chorioretinal folds and conjunctival chemosis presentation of combined Chiari 1 malformation and basilar invagination is unusual. To the best of our knowledge, this is the first case to be reported with this unique clinical presentation. It is most important to be aware that unilateral and intermittent chorioretinal folds associated with conjunctival chemosis may be signs of intracranial disease.

Using a flexible polarizable potential, the stable structures of H − (H 2 ) n (D 2 ) p clusters with fixed total size n + p = 32 have been investigated by means of path-integral molecular dynamics simulations as a function of composition. The most stable phase is found to be reverse core-shell, in which the heavier deuterium molecules reside outside. This result contrasts with neutral clusters, in which deuterium preferentially occupies internal sites. This purely quantum effect is interpreted to originate from the significant weakening of hydrogen covalent bonds in the vicinity of the ionic impurity and its lowering of zero-point energy that affects H 2 more than D 2 .

Supplying high voltage radio frequency (RF) is a critical part of ion trapping system due to impedance mismatching between RF source and the ion trap. A helical resonator has been constructed in order to deliver narrow bandwidth and high voltage RF to the ion trap for stable confinement of ions. The performances of the helical resonator have been studied for different capacitive load of the ion trap. Both the resonant frequency and quality factor of the resonator show strong dependence on external capacitive loads.

Summary Objectives To describe whether body mass index (BMI) is a clinically meaningful predictor of patient reported outcomes following primary total hip replacement (THR) surgery. Design Combined data from prospective cohort studies. We obtained information from four cohorts of patients receiving primary THR for osteoarthritis: Exeter Primary Outcomes Study (EPOS) ( n = 1431); EUROHIP ( n = 1327); Elective Orthopaedic Centre ( n = 2832); and St. Helier ( n = 787). The exposure of interest was pre-operative BMI. Confounding variables included: age, sex, SF-36 mental health, comorbidities, fixed flexion, analgesic use, college education, OA in other joints, expectation of less pain, radiographic K&L grade, ASA grade, years of hip pain. The primary outcome was the Oxford Hip Score (OHS). Regression models describe the association of BMI on outcome adjusting for all confounders. Results For a 5-unit increase in BMI, the attained 12-month OHS decreases by 0.78 points 95%CI (0.27–1.28), P -value 0.001. Compared to people of normal BMI (20–25), those in the obese class II (BMI 35–40) would have a 12-month OHS that is 2.34 points lower. Although statistically significant this effect is small and not clinically meaningful in contrast to the substantial change in OHS seen across all BMI groupings. In obese class II patients achieved a 22.2 point change in OHS following surgery. Conclusions Patients achieved substantial change in OHS after THR across all BMI categories, which greatly outweighs the small difference in attained post-operative score. The findings suggest BMI should not present a barrier to access THR in terms of PROMs.

Traditional literature emphasizes the role of foreign capital, especially foreign direct investment (FDI) in explaining the high growth rates that many emerging economies have enjoyed during 1990s and 2000s. The present paper accepts this conventional wisdom but argues that the FDI has also created problems of urban sprawl and congestion that would not be so intense if economic development had primarily come from domestic sources. This is because the FDI is typically concentrated in urban areas that abound in manufacturing and it neglects the rural areas where agriculture predominates. The paper suggests that a small tax on foreign capital tends to mitigate the side effects of foreign investment.

It is well known that nations with high trade deficits normally have higher interest rates than those with surplus or balanced trade. However, such has not been the case with the USA, which has seen a relentless trade deficit since 1982. Its interest rates have been lower than those prevailing in many trade-surplus nations. Furthermore, these rates fell even as the trade shortfall shot up, generating an interest-rate paradox. This paper demonstrates that, unlike for other nations, the rising trade deficit itself became the cause of lower US interest rates, and this happened because of the world's strong interest in maintaining a high value of the dollar.

We construct a general equilibrium model of trade and show that an economy can experience technological progress and declining real wages provided that it is open to trade and import demand is sufficiently inelastic in both countries. This is a puzzling outcome so far as marginal productivity paradigm is concerned. In this context we demonstrate that new technology works differently in a closed vs an open economy. In an open economy, technical improvements may generate a fall in labor real earnings, but not in a closed economy. In addition, technical progress in manufacturing must increase manufacturing–service wage gap according to marginal productivity doctrine. We show that the opposite outcome can occur theoretically in an open economy—yet another seemingly puzzling labor market outcome.

Objective Quantitative sensory testing (QST) and questionnaire-based assessments have been used to demonstrate features of neuropathic pain in subjects with musculoskeletal pain. However, their direct relationship has not been investigated in the community. The purpose of this study was to conduct an observational study to describe the characteristics of joint pain and to examine the relationship between QST measures and the PainDETECT Questionnaire (PD-Q). Methods Warm detection, heat pain, and mechanical pain thresholds as well as mechanical pain sensitivity over the sternum were determined and the PD-Q scores were calculated in a cross-sectional study of 462 participants in the Chingford Study. Comparisons were made between subjects with and those without joint pain. Logistic regression modeling was used to describe the association between neuropathic pain features, as determined by the PD-Q score, and each of the QST measures individually, adjusting for age, body mass index, and use of pain-modifying medications. Results A total of 66.2% of the subjects reported recent joint pain, with a median average pain severity of 5 of 10. There was increased sensitivity to painful stimuli in the group with pain as compared to the pain-free group, and this persisted after stratification by pain-modifying medication use. While only 6.7% of subjects had possible neuropathic pain features and 1.9% likely neuropathic pain features according to the standard PD-Q thresholds, features of neuropathic pain were common and were present in >50% of those reporting pain of at least moderate severity. Heat pain thresholds and mechanical pain sensitivity were significantly associated with features of neuropathic pain identified using the PD-Q, with an odds ratio (OR) of 0.88 (95% confidence interval [95% CI] 0.79–0.97; P = 0.011) and an OR of 1.24 (95% CI 1.04–1.48; P = 0.018), respectively. Conclusion QST measures and the PD-Q identified features of neuropathic pain in subjects in this community-based study, with significant overlap between the findings of the two techniques.

Objective:Genetic factors and abnormalities of joint morphology are important in the aetiology of hip osteoarthritis (OA). The extent to which genetic influences are manifest through joint morphology has undergone limited investigation. Using a cohort with an hereditary predisposition to end-stage hip OA and a control group with no inherited risk, we aimed to identify associations with abnormal joint morphology and clinical features.Design:One hundred and twenty-three individuals (mean age 52 years) with a family history of total hip arthroplasty (THA) (termed ‘sibkids’) were compared with 80 spouse controls. Morphology was assessed using standardised radiographs and cam, dysplasia, and pincer deformities defined. Regression modelling described the association of cohort with abnormal joint morphology, adjusting for confounders [age, gender, body mass index (BMI), OA, and osteophyte].Results:Sibkids had an odds ratio of 2.1 [95%confidence interval (CI) 1.3–3.5] for cam deformity. There were no differences in the prevalence of dysplasia or pincer deformities. In both groups, hips with cam deformities or dysplasia were more likely to have clinical features than normal hips [odds ratio (OR) 4.46 (1.8–11.3), and 4.40 (1.4–14.3) respectively]. Pincer deformity was associated with positive signs in the sibkids but not in the controls (OR 3.0; 1.1–8.2).Discussion:After adjustment for confounders that cause secondary morphological change, individuals with an hereditary predisposition to end-stage hip OA had a higher prevalence of morphological abnormalities associated with hip OA. Sibkids were more likely to demonstrate clinical features in the presence of pincer deformity, suggesting that the genes are acting not only through abnormal morphology but also through other factors that influence the prevalence of pain.

Using a Heckscher–Ohlin model, this paper re-examines Robert Mundell's famous thesis that free trade and unimpeded capital mobility are perfect substitutes. Under very general conditions which, according to many economists, have caused international convergence of factor rewards, we show that in a polluted environment free trade is inferior to free international investment. This happens even though commodity prices and factor rewards are the same with both policies. The practical side of our thesis is that the world will be better off by reducing the volume of trade while removing all barriers to foreign direct investment that at present hamper the service industries.

The purpose of this paper is to incorporate the currently mushrooming phenomenon of outsourcing into the standard two-sector, two-factor Heckscher–Ohlin model of international trade. We first show how outsourcing modifies a firm's production function, and then demonstrate that outsourcing generally raises the return to capital and lowers the real wage, although the nation's GDP rises in proportion to the value-added in the outsourcing industry. Furthermore, the output of the outsourcing sector may actually fall even though its unit cost goes down; the output of the other sector then rises. By contrast, employment in the outsourcing sector may actually rise.

Cyclic mechanical loads applied to the skeleton from habitual physical activity result in increased bone formation. These loads lead to dynamic pressure gradients and oscillatory flow of bone interstitial fluid, which, in turn, exposes cells resident in the bony matrix to oscillatory fluid shear stress. Dynamic fluid flow has previously been shown to be a potent anabolic stimulus for cultured osteoblasts. In this study, we used cDNA microarrays to examine early phase, broad-spectrum gene expression in MC3T3-E1 osteoblasts in response to physical stimulation. RNA was harvested at 30 min and 1 h post-stimulation. RNA was used for microarray hybridization as well as subsequent reverse transcription polymerase chain reaction (RT-PCR) validation of expression levels for selected genes. Microarray results were analysed by both functional and expression profile clustering. We identified a small number of genes at both the 30 min and 1 h timepoints that were either upregulated or downregulated with flow compared to no-flow control by twofold or more. From the group of genes upregulated at 30 min, we selected nine for RT-PCR confirmation. All were found to be upregulated by at least twofold. We identify a novel set of early response genes potentially involved in mediating the anabolic response of MC3T3 osteoblasts to flow, and provide functional groupings of these genes that may shed light on the relevant mechanosensory pathways involved.

Outsourcing has become an increasingly contentious subject ever since N. Gregory Mankiw remarked in 2004 that outsourcing is just another way of doing international trade, and must be beneficial to the nation, including the workers. We construct a simple two-sector specific-factor model and explore the validity of Mankiw's remarks. We find his ideas are valid when the country does not produce any outsourced factor's work at home in that both the laborers and the nation benefit. But when some outsourced factor cum intermediate good is also produced at home, the nation still benefits but the workers may suffer.

We offer a new paradigm to understand the effects of trade on factor rewards. It utilizes the classical-Keynesian model, and shows that normally a country’s trade deficit hurts labor by lowering the real wage, but benefits the owners of capital. The effects of tariffs on factor rewards and employment are opposite to those of the trade deficit, which falls with a rise in the tariff rate. Countries with trade shortfalls unambiguously benefit from their tariffs, because laborers far outnumber capitalists, who suffer from the declining interest rate. Thus, tariffs lead to a rise in social welfare in trade-deficit countries.

It is well known that cyclic mechanical loading can produce an anabolic response in bone. In vivo studies have shown that the insertion of short-term recovery periods (10–15 s) into mechanical loading profiles led to an increased osteogenic response compared to continuous cyclic loading of bone. Although this is suggestive of temporal processing at the bone cell level, there is little evidence to support such a hypothesis. Therefore, the current study investigated the cellular mechanism of bone's response to rest inserted vs. continuous mechanical loading. Cell responses to rest inserted mechanical loading were quantified by applying oscillatory fluid flow (OFF) to osteoblastic cells and quantifying real-time intracellular calcium [Ca 2+ ] i , prostaglandin E 2 (PGE 2 ) release, and osteopontin (OPN) mRNA levels. Cells were exposed to OFF (1 Hz) at shear stresses of 1 and 2 Pa with rest periods of 5, 10, and 15 s inserted every 10 loading cycles. The insertion of 10 and 15 s rest periods into the flow profile resulted in multiple [Ca 2+ ] i responses by individual cells, increased [Ca 2+ ] i response magnitudes, and increased overall percent of cells responding compared to continuously loaded control groups. We determined the source of the multiple calcium responses to be from intracellular stores. In addition, rest inserted OFF led to similar levels of PGE 2 release and increased levels of relative OPN mRNA compared to cells exposed to continuous OFF. Our study suggests that the cellular mechanism of bone adaptation to rest inserted mechanical loading may involve modulation of intracellular levels of calcium (frequency, magnitude, percent of cells responding).

Mechanical loading is an important regulator of bone formation and bone loss. Decreased osteoblast number and function are important cellular mechanisms by which mechanical disuse leads to decreased bone formation. Decreased osteoblast number may be a result of decreased osteoprogenitor proliferation, differentiation, or both. However, the effects of cellular level physical signals on osteoprogenitors are not well understood. In this study, we examined the effects of loading induced oscillatory fluid flow (OFF), a potent regulator of osteoblastic cell function, on marrow stromal cells (MSCs). MSCs subjected to OFF exhibited increased intracellular Ca2+ mobilization. In addition, MSCs exhibited increased proliferation and increased mRNA levels for osteopontin and osteocalcin genes. Collagen I and core binding factor 1 mRNA levels did not change. MSCs subjected to OFF also exhibited decreased alkaline phosphatase activity. These results suggest that MSCs are mechanosensitive and that Ca2+ may play a role in the signaling pathway.

This paper presents a framework which simplifies the task of developing, deploying, and managing complex, integrated, and standards-compliant eGovernance solutions. The framework enables development, configuration, integration, and management of solutions at a higher semantic level. It also provides commonly used services such as access to citizen and property records, access control and authentication services, public key infrastructure, and support for digital signatures. The ability to manage solutions at a higher semantic level enables administrators who are not proficient in programming to customize solutions in order to address specific needs of the different national, state, and local governments. This includes the ability to customize interfaces for multiple local languages used in government transactions and to customize workflows to conform to the organizational structure and policies to manage access to and retention of government records.

The present study was designed to elucidate the mechanisms accounting for disruption of the normal function of the testis exposed to various levels of Pb. Three different doses of Pb (10, 50, 200mg Pb/kg body weight per d) were given orally to male Portan rats (groups 2, 3, 4). Zn (1mg Zn/kg body weight per d) was also given with Pb (50mg Pb/kg body weight per d) in group 5. Treatments continued for 3 months. Plasma luteinizing hormone and follicle-stimulating hormone concentrations were found to be decreased in Pb-exposed rats. This was in turn reflected in the appreciable decline in fertility status. In cell kinetic studies, significant declines in various cell populations (preleptotene, pachytene, young (step 7) spermatids and mature (step 19) spermatids) were seen. However, in group 5 after Zn supplementation, hormone levels, cell numbers and fertility status were found to be close to normal. It is concluded that Pb might act at maturation level to cause conspicuous degenerative changes in the testis; Zn supplementation protected against these effects.

The paper explains most, if not all, observations made by the empirical literature regarding the behavior of skilled and unskilled real wages in the United States, especially those since 1980. Generalizing the Stopler–Samuelson theorem, the authors show that the nontraded sector is critical to explaining the effects of changes in the price of traded goods on relative and absolute wages. Factor-intensities play their role as in the traditional Stolper–Samuelson model, but the output of the nontraded sector matters as well. Specifically, freer trade benefits capital and hurts both the skilled and unskilled labor if the import as well as the nontraded sectors contract. This is a new result to the literature on Stolper–Samuelson issues.

This paper modifies the simple classical model by introducing capacity utilization that varies across the course of the business cycle. By making the capacity usage a choice variable that turns out to be sensitive to changes in the price level, we show that the classical model loses its fundamental feature, namely the neutrality of money. In our generalized framework, a rise in money supply improves upon all the real variables if the economy suffers from excess capacity, as in recessions and depressions. We demonstrate that our model describes the various economic cross-currents during the Great Depression extremely well. Thus, monetary policy emerges with an activist role even in a generally classical setting.

Economists universally regard tariffs to be inflationary and free trade to be deflationary, a view that this paper challenges. It is argued that while rotectionism has generally created inflation in developing economies, the experience of the United States was totally different. Tariffs in the US were never associated with rising prices, and trade liberalization with declining prices. High tariffs were always followed by sharp drops in the cost of living. A theoretical model is developed to explain the deflationary effects of tariffs in the United States. Thus tariffs produce inflation only in nonmarket or ualistic developing economies, but not in advanced economies.

In this paper we develop a simple general equilibrium model of trade to analyze the impact of tariffs and technical progress on the equilibrium rate of unemployment. We demonstrate that if a country imposes a tariff its equilibrium rate of unemployment is likely to rise, whereas the impact of technology on equilibrium unemployment depends on the labor intensity of the two sectors.

In this paper we present a model that highlights the relationship between international trade and environmental pollution. It includes a small open economy that produces a domestic composite good and imports another composite good and energy products. The pollution is created by local production, global production and transportation. Given this model we demonstrate that free trade within the current political and economic context may produce a suboptimal level of welfare. The rationale is based upon the argument that transportation is energy-intensive and that, therefore, trade itself is a source of pollution. Consequently, under certain global conditions the introduction of an energy tariff in a small open economy raises social welfare and is superior to free trade. A consumption tariff adopted by a single nation will not have similar consequences because it has no impact upon local usage. However, when a consumption tariff is globally adopted there is the opportunity for a net benefit. Finally, we argue that a global tariff that raises both the price of energy and the price of the imported composite good may generate the greatest increase in welfare by reducing both energy-intensive production and energy-intensive trade.

When the world shifted to the regime of flexible exchange rates after 1970, economists expected that large trade imbalances would soon disappear. Instead, such imbalances not only persisted but soared in the 1980s and 1990s, in spite of significant changes in important currencies such as the yen, the mark and the dollar. This paper reports that manufacturing importers tend to suffer trade deficits whereas exporters of manufacturing products tend to enjoy trade surpluses. The reason lies in the higher rates of productivity growth experienced by exporters of manufactures.

In the last ten years, a number of economists have tried to explain the observed decline or stagnation in the real wages of the US labor force in spite of slow but steady rise in labor productivity. This paper reports a similar affliction for the Japanese labor market since 1973. The explanation for stagnant wages in spite of respectable productivity gains in Japan lies in the vast appreciation of the yen versus the dollar, and ultimately in the highly regulated retail distribution.

This paper argues that not a single proposition of the modern theory of free trade is upheld by the recent experience of the United States. Freer trade is supposed to raise GNP growth and productivity growth as well as the living standard. Until 1972, when the US was practically a closed economy with a trade/GNP ratio averaging a low of 12%, GNP growth was 3.8%, productivity growth was 2%, and real wages had been rising for 150 years. Since 1972, the trade/GNP ratio has been rising steadily, US GNP growth has been only 2.5%, productivity growth is below 1%, and real wages have been falling for over three-quarters of the labor force.

This paper develops a two-sector general equilibrium model to examine the impact of technical progress, factor accumulation, labor growth, unemployment, trade policy, and the government's antipoverty programs on the rate of poverty. the results are then tested empirically using the data regarding the United States. We find that low unemployment, productivity growth, and government transfers have the expected effects of alleviating poverty; but trade liberalization has the unexpected effect of being associated with a major increase in poverty-a result contradicting traditional views.

The purpose of this paper is to explode the myth of free trade. Productivity and real wages in the United States rose sharply between 1950 and 1972, but since then real earnings have been falling in spite of a continuous rise in productivity. It turns out that America was more or less a closed economy until 1972, as its trade/GNP ratio was close to 10%; but since then it has become an open economy. the theoretical model shows how real wages may fall in an open economy, but not in a closed economy, in spite of rising productivity.

In this paper, the authors analyze the factors determining the pattern of trade between underemployed economies. They find, among other things, that a low-wage, land-abundant country exports the land-using, labor-intensive product to a high-wage, capital-abundant country. The authors also find conditions under which a high-wage, capital-rich country may export the labor-intensive product (the Leonteif paradox). Copyright 1990 by The London School of Economics and Political Science.

Objective: To determine appropriate terminology for addressing women in pregnancy. Design: 100 women (aged 15–50) were asked to fill in a questionnaire using one of the six choices provided for addressing women in pregnancy. Setting: Antenatal clinic of a teaching hospital. Results: Preferences vary according to context but simple terms like mother-to-be and pregnant women were more popular than client, consumer and maternant. Conclusion: No single terminology for addressing women in pregnancy wins all round approval but simple softer terms like Mother-to-be please a vast majority.

In this paper we provide a synthesis between the neoclassical and the Heckscher-Ohlin models of international trade by developing the properties of a two-sector, three-factor model. The neoclassical model, where one or more factors are specific to one or both industries, and the Heckscher-Ohlin model, where two (or all factors) are nonspecific, then can be analyzed as special cases of our model. The theorems by Rybczynski, Stolper and Samuelson, Jones and Chipman, among others, are reexamined in terms of our generalized model.

In this paper, we introduce diminishing returns to scale in Brecher's model of international trade with unemployment and then investigate some issues embodied in the theory of international trade. Our principal results are that tariffs need not improve a country's terms of trade and that capital accumulation also need not result in a predictable change in the terms of trade.

As Corden and Findlay (1975) have shown, the mobile capital Harris-Todaro model has certain curious properties, viz that capital accumulation unambiguously increases unemployment whereas labour force growth reduces unemployment. In this paper we show that introduction of labour turnover cost in the manufacturing sector dampens the above paradoxical results on one hand, and strengthens the interesting properties of the model on the other.

The theory of international investment is integrated to the monetary approach to balance of payments. It is shown that in the short run when the level of international investment is given a devaluation may not improve the balance of payments even if the Marshall-Lerner condition is met. If the devaluing country is a net importer of capital, then the chances for a successful devaluation are small. When the level of international investment is variable, a devaluation may not help balance of payments even if goods are gross substitutes. It is also shown that the effects of devaluation on international investment crucially depends on the movement of the terms of trade.

The purpose of this paper is to examine the implications of uncertainty for resource allocation, real income, and income distribution in terms of a simple two-sector general equilibrium model of a small country where uncertainty is introduced by assuming that production in one sector occurs in a stochastic environment. Assuming decreasing risk aversion, we show that an increase in uncertainty causes the movement of the resources away from the uncertain sector, a decline in expected real income, and a shift in the distribution of income against the factor employed intensively by the uncertain sector.

Using a model of an economy producing one non-traded good, one traded intermediate good and one traded final good, we have (1) derived plausible conditions under which the output of traded goods responds normally (or positively) to their relative prices, despite the presence of non-traded goods, which in earlier models have produced perverse results. (2) shown that the Metzler paradox continues to hold but under different sufficient conditions. Specifically, a tariff fails to be protective, provided the foreign elasticity of import demand falls short of the home marginal propensity to consume the non-traded good. (3) shown that Corden's celebrated theorem that for a small country a tariff is inferior to an equivalent production subsidy is invalid in a world where intermediate goods are traded.

This paper examines the impact of the presence of a forward exchange market on the financial and operational decisions of a multinational firm. The study concentrates especially on the effects of increased uncertainly and increased risk aversion on the part of the multinational firm. It is shown that the presence of the forward market allows the firm to respond to changes in uncertainly and risk aversion by adjusting its transactions in the forward market while leaving its production and sales decisions unchanged. The forward market, thus, promotes stability with respect to the operational as opposed to the financial variables; and its also makes it possible to adopt decentralized decision making.© 1982 JIBS. Journal of International Business Studies (1982) 13, 59–70

The various paradoxes of social choice uncovered by Arrow [1], Sen [10] and others1 have led some writers to question the basic assumption of a binary social choice function underlying most of these paradoxes. Schwartz [8], for example, proves an important theorem which may be considered to be a generalization of the famous paradox of Arrow,2 and then lays the blame for this paradox on the assumption of a binary social choice function.3 He then proceeds to define a type of choice functions which, like binary choice functions, define the best elements in sets of more than two alternatives on the basis of binary comparisons, but which, as he claims, have an advantage over binary choice functions, in so far as they always ensure the existence of best elements for sets of more than two alternatives irrespective of the results of binary comparisons.4 The purpose of this paper is to show that even a considerable weakening of the assumption of a binary social choice function does not go very far towards solving some of the paradoxes under consideration, and that if replacing the requirement of a binary social choice function by a Schwartz type social choice function solves these paradoxes, it does so only by violating the universally acceptable value judgment that in choosing from a set of alternatives, society should never choose an alternative which is Pareto inoptimal in that set (i.e., the socially best alternatives in a set should always be Pareto optimal). This argument is substantiated with the help of an extended version of Sen's [10] paradox of a Paretian liberal, and thus a by-product of our analysis is a generalization of the theorem of Sen [10]. The argument itself, however, is more general and applies also to the impossibility result proved by Schwartz [8].

Summary Objective Femoroacetabular Impingement (FAI) and Acetabular Dysplasia are common deformities, which have been implicated as a major cause of hip osteoarthritis (OA). We examined whether these subtle deformities of the hip are associated with the development of radiographic OA and total hip replacement (THR) in women. Design A population-based, longitudinal cohort of 1003 women underwent pelvis radiographs at years 2 and 20. Alpha Angle, Triangular Index Height, Lateral Centre Edge (LCE) angle and Extrusion Index were measured. An alpha angle of greater than 65° was defined as Cam-type FAI. Radiographic OA and the presence of a THR were then determined at 20 years. Results Cam-type FAI was significantly associated with the development of radiographic OA. Each degree increase in alpha angle above 65° was associated with an increase in risk of 5% (Odds Ratio (OR) 1.05 [95% confidence interval (CI) 1.01–1.09]) for radiographic OA and 4% (OR 1.04 [95% CI 1.00–1.08]) for THR. For Acetabular Dysplasia, each degree reduction in LCE angle below 28° was associated with an increase in risk of 13.0% (OR 0.87 [95% CI 0.78–0.96]) for radiographic OA and 18% (OR 0.82 [95% CI 0.75–0.89]) for THR. Conclusions This study demonstrates that Cam-type FAI and mild Acetabular Dysplasia are predictive of subsequent OA and THR in a large female population cohort. These are independent of age, BMI and joint space and significantly improve current predictive models of hip OA development.