ABSTRACT Radiation exposure to the surgeon is a concern in spinal surgery， especially with the increasing popularity of minimally invasive spinal surgery techniques. Three-dimensional (3D) image guidance used in conjunction with cone beam computed tomography (cbCT) has a theoretical advantage of decreased radiation exposure to the surgeon and operating room (OR) staff. Radiation scatter to the environment immediately surrounding a CT scanner during acquisition of a CT scan is a known entity. This in vivo study measures the radiation exposure to the surgeon when using cbCT registration in 3D image-guided spinal surgery. Two badge dosimeters were worn by the surgeon (EWN)， one on the right waistband of the surgeon's scrubs and the other located over the thyroid area during 25 consecutive spinal surgery cases in which cbCT was used in conjunction with 3D image guidance. No lead protection was worn by the surgeon. The cbCT device was used for registration of the anatomy and to confirm adequate instrumentation placement. The surgeon stood behind a clear lead shield in the same location during every spin of the cbCT device. After the 25th case， the badge dosimeters were sent to the radiology department for analysis. Overall， 63 cbCT spins were accomplished in 25 patients. A total of 228 screws were placed into spinal levels spanning from C2 to the ileum. No complications resulted from instrumentation placement or the use of image guidance.Analysis of both badge dosimeters revealed 0 millirem (mRem) exposure. Our study demonstrates that no radiation exposure to the surgeon occurs in cbCT-based， 3D image-guided spinal surgery procedures. Additionally， radiation scatter does not result in surgeon radiation exposure during patient registration if the surgeon stands behind a lead shield 10 feet from the cbCT device and not in direct line with the opening of the cbCT tube.
The migraine headache involves activation and central sensitization of the trigeminovascular pain pathway. The migraine aura is likely due to cortical spreading depression (CSD)， a propagating wave of brief neuronal depolarization followed by prolonged inhibition. The precise link between CSD and headache remains controversial. Our objectives were to study the effect of CSD on neuronal activation in the periaqueductal grey matter (PAG)， an area known to control pain and autonomic functions， and to be involved in migraine pathogenesis. Fos-immunoreactive nuclei were counted in rostral PAG and Edinger–Westphal nuclei (PAG–EWn bregma −6.5mm)， and caudal PAG (bregma −8mm) of 17 adult male Sprague–Dawley rats after KCl-induced CSD under chloral hydrate anesthesia. Being part of a pharmacological study， six animals had received， for the preceding 4 weeks daily， intraperitoneal (IP) injections of lamotrigine (15mg/kg)， six others had been treated with saline， while five sham-operated animals served as controls. We found that the number of Fos-immunoreactive nuclei in the PAG decreased after CSD provocation. There was no difference between lamotrigine- and saline-treated animals. The number of CSDs correlated negatively with Fos-immunoreactive counts. CSD-linked inhibition of neuronal activity in the PAG might play a role in central sensitization during migraine attacks and contribute to a better understanding of the link between the aura and the headache.
The article focuses on the MPEG-4 services deployed by broadcast service provider GlobeCast Australia. It starts its MPEG-4 service with channel partner Radio Television of Serbia (RTS) satellite (SAT)， the Australian arm of EURO World Network (EWN) that operates a Direct-to-Home (DTH) and Internet Protocol (IP) service using GlobeCast Australia DTH distribution on Optus D2. It also informs that RTS SAT will be available in both MPEG-2 and MPEG-4 until the end of the year.
Cynomolgus monkeys underwent unilateral panretinal scatter photocoagulation (PRP) and/or nasal and temporal horizontal retinal meridional photocoagulation (HRMP) with xenon arc or argon or krypton laser light. Shortly thereafter， in the PRP-treated eyes， accommodative responsiveness to topical eserine and electrical stimulation of the Edinger-Westphal nucleus (EWN) was diminished， accommodative responsiveness to intramuscular (i.m.) pilocarpine was enhanced， and the number of muscarinic receptors in the ciliary muscle was reduced compared to the contralateral controls. In most instances， these parameters returned to normal over 6–12 wks and the abnormalities could be induced again by another round of PRP. However， in some PRP-treated eyes， accommodative responsiveness to EWN stimulation and topical eserine remained subnormal permanently (> 1 yr). Shortly after HRMP alone， accommodative responses to i.m. pilocarpine， topical eserine， and central stimulation did not differ markedly in the treated and contro...
摘 要： “人怕孤，树怕枯。”张先生5个月来花了1800元找人聊天。其情节，犹如赵本山、宋丹丹小品《钏点工》中演绎的“陪聊”服务。
Public Disclosure AuthorizedWPS5784Policy Research Working Paper 5784Public Disclosure AuthorizedDebt Overhang in Emerging Europe?Martin BrownPhilip R. LanePublic Disclosure AuthorizedPublic Disclosure AuthorizedThe World BankEurope and Central Asia RegionOffice of the Chief EconomistAugust 2011Policy Research Working Paper 5784AbstractThis paper assesses the extent to which debt overhang At the microeconomic level， the potential for debtposes a constraint to economic activity in Emerging overhang in the corporate sector is limited to a fewEurope， as the region emerges from the recent financial countries： Latvia， Lithuania， Estonia， and Slovenia.and economic crisis. At the macroeconomic level， it Due to the low incidence of household debt， hardly anyfinds that the external imbalance problem for Emerging country， except Estonia， seems to face a threat of debtEurope has been in most cases more one of flows (high overhang in the household sector. The strong increasecurrent account deficits in the pre-crisis years) rather in non-performing loans compared with pre-crisis bankthan large stocks of external debt. A high reliance on profitability suggests that debt overhang in the bankingequity funding means that net external debt is far lower sector is a threat in Ukraine， Latvia， Lithuania， Hungary，than net external liabilities. Domestic balance sheets Georgia， and Albania. Financial integration of Emerginghave expanded quite rapidly but sector liabilities remain Europe seems to have contributed to the transmission ofrelatively low compared with advanced economies. With the crisis to the region. At the same time， this integrationthe important exception of Hungary， public debt levels is helping the region in managing the crisis by concertedalso remain relatively low in Emerging Europe. actions of the major players.This paper is a product of the Office of the Chief Economist， Europe and Central Asia Region. It is part of a larger effort bythe World Bank to provide open access to its research and make a contribution to development policy discussions aroundthe world. Policy Research Working Papers are also posted on the Web at http：//econ.worldbank.org. The authors may becontacted at (University of St. Gallen) and (IIIS， Trinity College Dublin and CEPR).The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about developmentissues. An objective of the series is to get the findings out quickly， even if the presentations are less than fully polished. The papers carry thenames of the authors and should be cited accordingly. The findings， interpretations， and conclusions expressed in this paper are entirely thoseof the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank andits affiliated organizations， or those of the Executive Directors of the World Bank or the governments they represent.Produced by the Research Support TeamDebt Overhang in Emerging Europe?byMartin Brown and Philip R. LaneJEL： D10， D14， D22， E20， F34Keywords： debt overhang， household behavior， investment， consumptionDebt Overhang in Emerging Europe?11. IntroductionThe aim of this background paper is to assess the extent to which debt overhang poses aconstraint to economic activity in Emerging Europe， as the region emerges from the recentfinancial and economic crisis. The analysis covers the new member states of the EU (Bulgaria，Czech Republic， Estonia， Hungary， Latvia， Lithuania， Poland， Romania， Slovak Republic， andSlovenia) candidate and potential candidates of the EU (Albania， Bosnia and Herzegovina，Croatia， Macedonia， Serbia and Turkey) and Eastern Partnership countries (Armenia， Georgia，Moldova， Ukraine).We take a broad view of debt overhang， analyzing both its macroeconomic andmicroeconomic dimensions. At the macroeconomic level， we examine how external anddomestic sectoral balance sheets developed prior to and during the crisis. At the microeconomiclevel， we assess the distribution of debt across firms and households at the outset and during thecrisis. We further examine the loan losses suffered by the banking sector during the crisis andhow this may impact on their future lending.In relation to our macroeconomic analysis， we find that the external imbalance problemfor Emerging Europe has been in most cases more one of flows (high current account deficits inthe pre-crisis years) rather than large stocks of external debt. A high reliance on equity fundingmeans that net external debt is far lower than net external liabilities. In any event， currentaccount deficits have narrowed quite rapidly in most countries over 2008-2010. In relation todomestic sectoral balance sheets， these have expanded quite rapidly but sectoral liabilities remainrelatively low compared to advanced economies. However， the rapid expansion in credit doessuggest that non-performing loans could be problematic， due to deterioration in loan qualityduring intense credit booms. Finally， with the important exception of Hungary， public debtlevels remain relatively low in Emerging Europe. So long as the debts of other sectors are notsocialized， the risk of sovereign debt crises in these countries seems low compared to manyadvanced economies.At the microeconomic level， we first examine whether debt overhang in the enterprisesector may constrain future activity in the region. Using data from the EBRD 2009 BusinessEnvironment and Enterprise Performance Survey (BEEPS) we identify the share and type offirms which are highly leveraged in each country and assess what this may imply for corporateinvestment going forward out of the crisis. Comparing the share of highly leveraged firms bycountry to GDP contraction during the crisis we find that debt overhang is likely to pose ageneral threat to firm activity in only a limited number of the more advanced countries： Latvia，1Brown would like to thank Ralph De Haas and Franklin Steves (both EBRD) for sharing data and KarolinKirschenmann for valuable research assistance; Lane thanks Peter McQuade for research assistance; we thank JuanZalduendo for helpful feedback on an earlier draft. This paper was prepared as background to a forthcoming WorldBank report titled “Golden Growth： Restoring the Lustre of the European Economic Model.” The views expressed inthis paper are exclusively those of the authors and do not necessarily represent the views of the World Bank and itsaffiliated organizations or the Executive Directors of the World Bank and the governments they represent. All errorsand omissions remain entirely the responsibility of the authors. The authors may be contacted by electronic email to(University of St. Gallen) and (IIIS， Trinity College Dublin and CEPR).2Lithuania， Estonia， and Slovenia. Leverage levels among export-orientated firms and thewidespread contraction of export income in the region， suggests， however， that debt overhang inthe tradable sector may be an issue for a broader set of countries： Latvia， Lithuania Estonia，Slovenia， Macedonia， Bosnia， Turkey， the Slovak Republic， Serbia， the Czech Republic andCroatia. Finally， our firm-level analysis suggests that despite sharp depreciations in manycountries during the crisis， unhedged foreign currency borrowing by firms does not seem to be asource of debt overhang. The countries with a high incidence of unhedged FX loans experiencedonly minor depreciations during the crisis.We next examine the potential for debt overhang in the household sector by countryusing data from the 2010 EBRD Life in Transition Survey (LITS). We find that mortgage debtseems to have had a significant adverse impact on household consumption and investment duringthe crisis. However， due to the low incidence of mortgage debt in the region hardly any country，except Estonia， seems to face a threat of debt overhang. The use of credit cards is much morewidespread in the region than mortgage debt. However， credit card use has had a negligibleeffect on household income and investment during the crisis. It is unlikely therefore that creditcard debt may jeopardize future economic activity in the region. Our household-level analysisfurther suggests that FX mortgages hardly pose a threat to future household consumption andinvestment. Only a minor fraction of households in the region are exposed to foreign currencymortgages. Moreover those countries in which FX mortgages are most prevalent did notexperience major exchange rate shocks during the crisis.We also assess the potential for debt overhang in the banking sector due to thesignificant loan losses incurred in many countries of the region during the crisis. The strongincrease in non-performing loans (NPL) compared to pre-crisis bank profitability suggests thatdebt overhang in the banking sector is a threat in Ukraine， Latvia， Lithuania， Hungary as well asin Georgia and Albania. In the countries that face the most severe NPL problems， the share ofprivate credit extended to firms (60%) and households (40%) is similar to the sample average.This suggests that debt overhang in the banking sector of these countries is likely to affect bothsectors， with firms slightly more affected than households. We further assess the role of foreignbanks in mitigating or exacerbating the effects of the crisis in the region. A review of the recentevidence suggests that the financial integration of Emerging Europe has contributed to thetransmission of a crisis that had emerged unrelated to the local economic conditions. At thesame time， this integration helped the region in managing the crisis by concerted actions of themajor players (Vienna Initiative， IMF and EU stabilizing programs).In the final part of the paper， we examine the policy response in emerging Europe， both interms of pre-crisis policies and also the policy response during the crisis. We review the lessonsfrom previous crises in terms of dealing with debt overhang issues and offer a brief assessmentof current policy measures in emerging Europe.We find that authorities in most countries have focused on policy measures to curb FXlending and cushion the effects of exchange rate depreciations on existing FX borrowers，especially in the household sector. Our analysis suggests that these will have little effect onaggregate investment and consumption in the private sector. While FX lending may be apressing issue for financial stability， the low levels of unhedged FX borrowing by enterprises andthe low incidence of mortgage borrowing among households suggests that this can hardly affectaggregate output.3We discuss recent measures in selected countries (e.g. Latvia and Hungary) to shift theburden of debt from households to banks. Our assessment is that these measures may becounterproductive in view of future economic growth： the marginal debt levels of households inthe region suggests that over-indebtedness will hardly constrain economic activity in thehousehold sector， while debt overhang in the banking sector seems to already pose a greaterthreat.Finally we discuss whether authorities in the region should follow the example ofindustrialized countries in the recent crisis and East Asian countries at the end of the 1990s byusing public funds to take “toxic” assets off banks’ balance sheets. Our view is that suchmeasures may not be necessary： those countries in the region that have experienced substantiallosses in the banking sector are also characterized by a dominance of foreign-owned banks.These banks have shown the ability and willingness to support their subsidiaries in EmergingEurope even in times when they were facing substantial challenges in their home markets. Also，it seems both politically and economically infeasible that authorities in Emerging Europe coulduse taxpayer funds to subsidize the activities of a predominantly foreign-owned banking sector.The structure of the rest of this paper is as follows. We provide a brief overview of thedebt overhang literature in Section 2. In Section 3， we describe the evolution of the externalbalance sheets of emerging Europe over the last decade， differentiating between external debtand external equity positions. In addition， we analyze the dynamics of public debt and private-sector debts， plus sectoral balance sheets. We turn to micro-level evidence in Section 4， in whichwe examine debt levels at the level of firms， households and banks. We conclude with ourpolicy analysis in Section 5.2. Literature ReviewThe broad scope of our analysis is inspired by the multifaceted discussion of debtoverhang in the microeconomic and macroeconomic literature. The corporate finance literatureon debt overhang reaches back to Myers (1977)， who demonstrated that the existing level of debtcan alter the investment decisions of firms. In his framework， debt overhang refers to a situationwhere the expected payoff to existing creditors is less than the face value of their claims on thefirm. In such a case， the firm must use part of the profits from new investments to pay offexisting creditors. Shareholders of limited-liability firms will not internalize this positive“external” effect of their investment activity and may pass up profitable investmentopportunities.In parallel， a narrow definition of debt overhang in the household sector refers to asituation where over-indebted households forego investments in home improvement (Melzer2010) or household supply of labor (Mulligan 2008). In a broader sense， debt overhang can alsorefer to the negative impact of household debt on consumption levels， as in Olney (1999).Debt overhang in the banking sector has been put forward as the major reason for policyinterventions to remove toxic assets from bank balance sheets and recapitalize banks during therecent crisis (Philippon and Schnabl， 2009). In analogy to corporate debt overhang， debtoverhang in the banking sector is viewed as a situation in which the scale of the debt liabilities of4the banking sector (relative to the value of bank assets) distorts the lending decisions of thebanking sector.In the context of sovereign debt， Krugman (1988) defines debt overhang as a situation inwhich “the expected present value of future country transfers is less than the current face valueof its debt”. This corresponds to the notion of a Debt Laffer Curve， by which total repaymentsdecline beyond a threshold level of debt. A Debt Laffer Curve effect exists if the outstandinglevel of debt distorts investment and labor supply decisions and/or adversely affects economicpolicies to such an extent that total repayments shrink.At a macroeconomic level， a common usage is to identify the existence of debt overhangif the outstanding level of debt is associated with a reduction in the rate of economic growth (seeManzano and Rigobon 2001， Cordella et al 2005， Budina et al 2007 and Imbs and Ranciere2008， among others).2 Much of the initial literature focused on external debt， since the servicingof external debt has clear macroeconomic implications in terms of requiring a trade surplus insteady state. Typically， this requires an economy to undergo a real exchange rate depreciation.In turn， this can aggravate the debt problem， due to the feedback between the real exchange rateand the real value of the debt burden. In addition， the external dimension is especially interesting，since it is well understood that the enforcement of cross-border debts (especially sovereigndebts) is quite problematic.A large external debt generates an array of economic distortions. The classic example isthat high debt acts like a tax on investment， since an expansion in resources will largely beabsorbed by increased payments to outstanding creditors (Krugman 1988， Sachs 1989， amongothers). In similar vein， the incentive for a government to deliver growth-friendly policies isweakened， if domestic residents enjoy only a limited gain from extra output. In addition， a highoutstanding level of debt increases fragility in funding markets (Diwan and Rodrik 1992). Forinstance， the higher level of rollover risk that is associated with a large outstanding stock of debtmeans that new lenders may be unwilling to provide funds due to the risk of market disruptions.In turn， the concept of debt overhang inspired many proposals for debt relief during thel980s (Dooley 1986， Fischer 1989， Bulow and Rogoff 1989， amongst many others). In part， therationale for policy intervention was to coordinate across individual creditors， since the “freerider” problem means that individual creditors have an incentive to hold out for maximumrepayment. In part， however， subsidies from international financial institutions were used tobridge the gap between the minimum repayments required by creditors and the maximumrepayments that could be tolerated by debtors (Sachs 1989).The debt relief literature highlights that many different financial engineering solutions，with each allocating the costs of debt relief in different ways. Accordingly， there are criticaldistributional issues in designing a debt resolution scheme， which can lead to prolonged delays inachieving agreement. In addition to reductions in the net present value of debt， an additionalmechanism is to convert debt into an equity claim and/or make the level and timing ofrepayments contingent on the economic performance of the debtor. Such risk-sharing schemesenable greater transfers to creditors if performance is good. To avoid moral hazard problems，2There is also a recent theoretical literature on debt overhang that emphasizes its role in amplifying business cycles(Aguiar et al 2007， Occhino and Pescatori 2010).5such schemes are ideally based on exogenous factors， such as world interest rates or commodityprices (see Krugman 1988， among others).In relation to net external liabilities， there has been a major shift away from debtfinancing towards equity financing for emerging market and developing economies; conversely，many advanced economies have large net foreign debt liability positions that fund positive netforeign equity positions (Lane and Milesi-Ferretti 2007a， Lane and Shambaugh 2010).In some respects， the debt overhang problem can be interpreted as a liability overhangproblem， in the sense that total expected net outward transfers (whether debt payments or equitypayments) may influence incentives. Indeed， Lane and Milesi-Ferretti (2007b) emphasize that ahigh equity component in external liabilities means that more of the upside from future economicgrowth accrues to foreign investors. Moreover， to the extent that an equity return premiumexists， the average level of outward transfers should be higher， the greater is the equity share inexternal liabilities. However， in the other direction， equity-type liabilities are less risky thandebt-type liabilities due to the contingent nature of equity returns. In this way， an adversemacroeconomic shock can amplify the external debt burden but may be hedged in the case offoreign equity liabilities. Accordingly， if tail risk is a major source of debt overhang， this isameliorated by a greater role for equity-type instruments in external liabilities. Finally， aninteresting special case relates to external debt that is intermediated via foreign-owned affiliatesin the domestic banking system. In this case， the risk of external debt is attenuated since theequity in the capital base of the foreign-owned domestic banks provides a buffer that can absorblosses in the event of a negative shock.The accumulated empirical evidence provides some support for the overhang hypothesisin relation to external debt. Cordella et al (2005) study 79 developing countries over 1970-2002and find external debt above 15%-30% is associated with lower growth performance for thosecountries with good institutions.3 Imbs and Ranciere (2008) study 87 developing countries over1969-2002 and find a negative growth effect if the face value of external debt exceeds 60 percentof GDP (or if the present value of debt exceeds 40 percent of GDP). Moreover， they identifysome mechanisms by which debt overhang operates. In particular， they show that investmentdeclines and the conduct of economic policy deteriorates in the debt overhang zone. Accordingto the authors， these results are mostly driven by countries with poor property rights andunderdeveloped financial markets， under which external monitoring of borrowers is mostdifficult.4Reinhart and Rogoff (2010) study the relation between external debt and growthperformance for a group of twenty emerging market economies over a 200-year period. Inbivariate statistical analysis， these authors find a threshold of 60 percent of GDP， with a lowergrowth rate observed for countries with higher external debt levels.However， all of these studies focus on developing country studies. One reason is thatthere are no similar， long datasets on the external debts of advanced economies (partly due to the3These authors find that is no robust relation between debt and growth for countries with weak institutions. Onepossibility is that debt rescheduling is fully expected for such countries.4Arsanalp and Henry (2004) provide related evidence using data on the impact of announcements of debt reliefschemes on asset prices.6lower incidence of default on external debt among high-income countries). Accordingly， theirrelevance to advanced economies may be limited， in view of the greater degree of financialdevelopment and other structural differences. Moreover， the phenomenon of significant foreignequity liabilities is relatively recent (only growing rapidly since the early 2000s)， such thatstudies concerning external debt do not necessarily carry over to total external liabilities.Finally， these studies consider gross external debt. While foreign debt assets for these types ofcountries might have been relatively small in earlier periods， the growth in reserve positions overthe last decade means that there is a large divergence between gross external debt liabilities andnet external debt liabilities for many countries.As noted above， the debt overhang concept can also apply at the sectoral level and at thelevel of individual banks， firms and households in addition to the external dimension. There is agrowing literature that shows that high public debts are associated with lower output growth(Checherita and Rother 2010， Kumar and Woo 2010， Reinhart and Rogoff 2010).Kumar and Woo (2010) study a panel of 38 advanced and emerging economies over 1970to 2007. These authors find that public debt ratios above 90 percent are associated with lowersubsequent output growth， with the growth penalty substantially larger for emerging marketsthan for advanced economies. In particular， these authors estimate that a 10 percentage pointincrease in the debt ratio is associated with a growth slowdown of 0.15-0.2 percent in advancedeconomies but 0.3-0.4 percent in emerging economies. Moreover， they find that reducedinvestment is a key driver of the deterioration in growth performance.In a study of euro area member countries over 1970-2009， Checherita and Rother (2010)also find a negative growth threshold of around 90-100 percent for the debt ratio. However，these authors caution that the lower-bound confidence interval of 70-80 percent calls for greaterprudential policies at lower debt levels. In terms of mechanics， these authors find that highpublic debt adversely affects growth through several channels， including reductions in privatesaving and TFP growth. In a study of forty-four countries over two hundred years， the statisticalanalysis of Reinhart and Rogoff (2010) also suggests a 90 percent threshold ratio of public debt，beyond which growth performance deteriorates.It is important to emphasize that private-sector debt problems can induce a sovereign debtcrisis. Most directly， a government may choose to take over private liabilities， either forefficiency reasons or in response to political pressures. In turn， the existence of an implicit fiscalbackstop may lead to lower repayment discipline among private-sector creditors， especially ifdebt problems are sufficiently widespread in the population to render punishment threatsincredible (Arellano and Kocherlakota 2008). A similar logic applies if banks are taken intopublic ownership and private-sector debtors believe that government-owned banks will take asofter line in enforcing repayment. Accordingly， governments face a difficult problem indesigning resolution schemes for private-sector debts， in view of such moral hazard problems.In relation to sectoral debt overhang， the literature on the output losses associated withbanking crises is extensive (see Cerra and Saxena 2008， Furceri and Mourougane 2009 andInternational Monetary Fund 2009 for recent studies). There is also some evidence thatexcessive leverage at corporate and household levels may also damage macroeconomicperformance (Laeven and Laryea 2009， Laryea 2010).7In summary， the research literature provides an array of theoretical mechanisms that cangenerate a debt overhang effect， at either aggregate or sectoral levels. Moreover， the empiricalevidence does suggest that excessively-high debt levels can weigh down on macroeconomic orsectoral economic performance. However， the potential gains to any type of debt forgivenessprogram have to be set against the possible short-term and long-term costs of writing down debtlevels. In relation to the short-term costs， debt renegotiation costs can be substantial (both interms of lost output and financial reputation)， depending on the level of cooperation betweencreditors and debtors (see Panizza et al 2009 for a recent survey). As indicated above， there isalso the moral hazard risk by which the existence of a debt forgiveness program may reducerepayment discipline even among those that would meet their commitments under a stricterregime. In relation to the longer term， the weakening of creditor rights in a debt forgivenessprogram may raise the long-term cost of capital (Shleifer 2003).Furthermore， in terms of quantitative guidance， the empirical literature offers onlyindicative evidence. In particular， the bulk of the studies relate to lower-income countries， suchthat the guidance in terms of debt thresholds for advanced or upper middle income economiesmay be quite limited. Moreover， the results are sensitive to sample selection and the choice ofconditioning variables. Accordingly， in what follows， we mainly focus on cross-country andcross-group comparisons rather than seeking to place each country on either side of a fixedthreshold.3. External and Domestic Balance Sheets3.1 External Balance SheetsIn this section， we examine the evolution of the external balance sheets of emergingEurope. A highly-negative net foreign asset position may signal sustainability problems. Inparticular， if a substantial improvement in the net foreign asset position is required to ensuresustainability， this will typically require a turnaround in the trade balance. In turn， this mayinduce substantial real exchange rate depreciation (Lane and Milesi-Ferretti 2004). In addition，import compression may be achieved through a contraction in domestic demand， such thatexternal adjustment may be associated with domestic recessionary forces. The social andeconomic costs of this dynamic may tempt a country with large net external liabilities to look todebt restructuring or international financial assistance in order to smooth out the adjustmentprocess.Table 3.1 shows the net foreign asset position for the individual emerging Europeancountries for three years： 2002， 2007 and 2009. There is a clear difference between the EU newmember states and the other countries in terms of the growth in the net external position duringthe pre-crisis period. In particular， there was a near doubling of the net external liabilities of theformer group between 2002 and 2007， whereas there was only a marginal deterioration for thelatter group. Both groups have seen further deterioration between 2007 and 2009 but the gapbetween the two groups has closed slightly.Table 3.1a shows that the net foreign liability positions of the emerging European regionsare much more negative than for emerging Asia and emerging Latin America. The comparisonwith the Euro Periphery shows an important difference： whereas the expansion in net external8liabilities between 2002 and 2007 was similar across the two areas， the net external liabilities ofthe Euro Periphery continued to grow rapidly after 2007， whereas emerging Europe has seen amuch smaller deterioration during the crisis.Table 3.1. Net Foreign Assets， Percent of GDPCountry 2002 2007 2009New Member States Bulgaria -30 -95 -117Czech Republic -18 -45 -47Estonia -60 -79 -84Hungary -74 -96 -129Latvia -44 -80 -87Lithuania -37 -60 -62Poland -38 -58 -66Romania -24 -50 -66Slovak Republic -27 -61 -73Slovenia -2 -25 -39Candidates and Potential Candidates Albania -14 -28 -50Bosnia and Herzegovina -29 -36 -57Croatia -30 -103 -86Macedonia， FYR -40 -47 -66Serbia n/a n/a n/aTurkey -37 -49 -45Eastern Partnership Countries Armenia -64 -23 -48Georgia -64 -84 -121Moldova -93 -62 -76Ukraine -29 -23 -39Source： Updated EWN dataset based on Lane and Milesi-Ferretti (2007). Note： This table reports foreign assetminus foreign liabilities.Table 3.1a. Net Foreign Assets， Percent of GDPCountry 2002 2007 2009Euro Periphery -48 -77 -102Emerging Latin America -47 -24 -24Emerging Asia -15 0 -10New Member States -35 -65 -77Candidates and Potential Candidates -30 -52 -61Eastern Partnership Countries -63 -48 -71Source： Updated EWN dataset based on Lane and Milesi-Ferretti (2007). Note： These tables report foreign assetminus foreign liabilities.It might be argued that the debt component of the external balance sheet poses moreproblems than the equity component in relation to overhang issues. Accordingly， we show thenet debt and net equity positions in Table 3.2. For the new member states， Table 3.2 showssizeable growth in net debt liabilities between 2002 and 2007， from 2 percent of GDP to 18percent of GDP. There has been further expansion during the crisis， rising to 27 percent of GDPin 2009. Table 3.2 also shows that net equity liabilities are far greater than net debt liabilities forthe new member states. Moreover， the relative stability of net equity positions between 2007 and2009 also highlights the stabilizing role played by equity-type liabilities - the value of theseliabilities naturally falls with a decline in performance in these economies.A similar message holds for the other countries. Indeed， net debt liabilities for this groupactually fell between 2002 and 2007， before increasing during the crisis period. Between 2002and 2007， these countries saw rapid growth in net equity liabilities. Figure 3.1 shows the scatterof net equity versus net debt positions for 2009 for the whole sample of countries.9Table 3.2. Net Debt and Equity IIP， Percent of GDPNet Debt Net EquityCountry 2002 2007 2009 2002 2007 2009New Member States Bulgaria -8 0 -12 -23 -95 -105Czech Republic 33 14 9 -51 -60 -56Estonia -4 -33 -37 -57 -47 -46Hungary -19 -44 -60 -56 -51 -68Latvia -14 -46 -46 -29 -34 -40Lithuania -8 -27 -33 -28 -34 -29Poland -12 -16 -26 -26 -42 -40Romania -6 -11 -21 -18 -39 -45Slovak Republic 9 -3 -15 -36 -58 -58Slovenia 11 -15 -28 -13 -10 -10Candidates and Potential Candidates Albania 9 5 -7 -22 -33 -42Bosnia and Herzegovina -17 -1 -18 -12 -35 -39Croatia -12 -29 -39 -18 -73 -47Macedonia， FYR -8 2 -9 -32 -49 -57SerbiaTurkey -30 -17 -19 -7 -31 -26Eastern Partnership Countries Armenia -36 4 -6 -29 -27 -42Georgia -38 -19 -34 -26 -65 -87Moldova -55 -20 -27 -38 -42 -49Ukraine -14 5 5 -15 -27 -45Source： Updated EWN dataset based on Lane and Milesi-Ferretti (2007). Note： This table reports net debt which isinternational debt assets plus foreign exchange reserves minus international debt liabilities， and net equity which isinternational equity assets minus international equity liabilities..Table 3.2a compares the evolution of net debt and net equity for Emerging Europe to theEuro Periphery， Emerging Latin America and Emerging Asia. There are some strikingdifferences across these regions. While emerging economies in Latin America and Asiaaccumulated positive net debt positions between 2002 and 2009， only the Eastern Partnershipbloc in Europe saw a reduction in net debt liabilities. In contrast， the growth in net debtliabilities was most rapid for the Euro Periphery and the new member states.Table 3.2a. Net Debt and Equity IIP， Percent of GDPCountry Net Debt Net Equity2002 2007 2009 2002 2007 2009Euro Periphery 29 -3 -20 -78 -73 -81Emerging Latin America -23 3 7 -24 -27 -30
Nueva propuesta de desambiguación de sentidos de palabras para nombres en un sistema de búsqueda de respuestas
Este artículo describe el impacto de un algoritmo de Desambiguación de Sentidos de Palabras (WSD) para nombres en AliQAn， el sistema de Question Answering con el cual hemos participado en el CLEF-2005. Al aplicar el WSD tradicional， el rendimiento se decrementa en un 4.7% en el Mean Reciprocal Rank (MRR). Para resolver este problema， proponemos dos aplicaciones de WSD： (1) elegir un grupo de synsets en vez de uno como hace el WSD tradicional; (2) desambiguar las palabras inexistentes en EuroWordNet (EWN). Con nuestra propuesta de WSD el MRR se incrementa en un 6.3% en relación con el baseline sin WSD. Además， nuestra propuesta de WSD incrementa el MRR en un 11% respecto al WSD tradicional. Por último， la implementación de nuestro enfoque de WSD es computacionalmente eficiente gracias a un preprocesamiento de EWN. This paper studies the influence of a Word Sense Disambiguation algorithm for nouns on AliQAn， the Question Answering with which we have participated in the CLEF-2005. Applying the traditional WSD decreases the performance in 4.7% on the Mean Reciprocal Rank (MRR). To solve this problem， we propose two different uses of WSD： (1) to choose a set of synsets instead of the traditional use of WSD， in which only one synset is chosen; (2) to disambiguate the words not present in EuroWordNet (EWN). Using our proposal of WSD the MRR increases a 6.3% with regard to the baseline without WSD. Furthermore， our proposal of WSD increases the MRR with regard to the traditional use of WSD in an 11%. Finally， the implementation of our approach of WSD is computationally efficient by means of a preprocessing of EWN.
ABSTRACT Cynomolgus monkeys underwent unilateral PRP with xenon arc or argon or krypton laser light， employing burn intensity， size， spacing， and topography analogous to standard clinical (eg， Diabetic Retinopathy Study) treatment. Shortly thereafter， accommodative responsiveness to topical eserine and electrical stimulation of the EWN was diminished， accommodative responsiveness to systemic pilocarpine was enhanced， and the number of muscarinic receptors in the ciliary muscle was reduced in the PRP-treated eyes compared to the contralateral controls. In most instances， these parameters returned to normal over 6 to 12 weeks and the abnormalities could be induced again by another round of PRP. However， in some PRP-treated eyes， accommodative responsiveness to EWN stimulation and topical eserine remained subnormal permanently (greater than 1 year). Light and electron microscopy of the ciliary muscle and choroid confirmed the early interruption and degeneration and the subsequent regeneration of the intraocular parasympathetic nerves following PRP. These findings are similar to those seen after surgical removal of the ciliary ganglion and posterior ciliary nerves， and indicate that PRP produces an intraocular parasympathetic denervation of the ciliary muscle. This phenomenon may explain the loss of voluntary accommodation which can follow PRP in prepresbyopic humans. Three cynomolgus monkeys underwent nasal and temporal HRMP in one eye with the argon laser. One to four weeks later， accommodative responses to IM pilocarpine， topical eserine， and electric stimulation of the EWN did not differ markedly in the treated and control eyes. Five weeks after HRMP， posterior PRP was performed in the same eye， sparing the previously treated areas. One to four weeks later， accommodative responses in the PRP-treated eyes were clearly subsensitive to central electrical stimulation， but supersensitive to IM pilocarpine， compared to the contralateral controls. These findings indicate that extensive parasympathetic denervation of the ciliary muscle occurs following PRP but not following HRMP. Consequently， we infer that parasympathetic motor nerve fibers to the ciliary muscle do not travel preferentially with the LPCN， but rather travel primarily if not exclusively with the more numerous SPCN. If the monkey and the human are comparable， sparing the horizontal retinal meridians during clinical PRP so as not to disturb the LPCN will probably not help to preserve ciliary muscle function and accommodation.
Auditory evoked potentials in individuals at risk developing a psychosis, in first episode patients and those with chronic schizophrenia
Abstract： In 2010 the spent fuel of the German prototype fast breeder reactor KNK was returned from France to Germany. For the return and the interim storage 4 transport and storage casks of the type CASTOR(R) KNK were designed and fabricated by GNS Gesellschaft fur Nuklear-Service mbH. The casks were transported to Germany in December 2010 and stored in the interim storage facility ZLN operated by Energiewerke Nord GmbH (EWN). Due to there dual-purpose all CASTOR(R) casks have to fulfill the requirements of both fields of operation - transport and storage. After a minimum storage period of 40 years， a last transport to the final repository has to be carried out with the same requirements as for new casks. To be sure that the cask can be transported after the storage period the authorities require the renewal of the package design approval， normally each 5 or 10 years. In case of CASTOR(R) KNK the approval expires at October 2014. EWN and GNS are planning an extension of the validity period of the package design approval to 10 years. For this purpose an aging management report is necessary considering all stress factors， which are crucial for the rate of aging： Radiation， thermal and mechanical loads and corrosion.
Effects of Electro-warmed Needle of Inner-Mongolian Medicine on Serum TNF-α,ACTH and Corticosterone Contents in Fatigue Rats
OBJECTIVE： To observe the effect of electro-warmed needle (EWN， of Inner-Mongolian medicine) on fatigue rats' behavior， hypothalamic-pituitary-adrenocortex (HPA) axis activity and immune system so as to reveal its neuro-endocrino-immune mechanism. METHODS： Male SD rats were randomized into control (n=20)， model (n=20) and EWN (n=19) groups. Fatigue model was established by forcing the rat to swim in a water pool till exhaustion， once daily， continuously for 21 days. "Dinghui" (central spot over the bregmatic bone) and "Xinxue" (the center of the depression beneath the 7th thoracic vertebra) were punctured with silver needles which were warmed electrically by using a MLY-I Electrical Needle-warming Apparatus， once every 3 days， 7 sessions altogether. On the 21st day of modeling， swim-exhaustion duration (SED)， and immobility time and struggle times in tail suspension test were measured. Twenty-four hours after the last swim， the rats' serum TNF-alpha， ACTH an corticosterone contents were detected by enzyme linked immunosorbent assay (ELISA). RESULTS： Compared with control group SED， immobility time and struggle times in tail suspension test in model group decreased， increased and lowered respectively and significantly (P 0.05). Compared with control group， serum TNF-alpha， ACTH and corticosterone contents in model group increased significantly (P < 0.01)， while in comparison with model group， the 3 indexes of EWN group were significantly lower (P < 0.01， 0.05). CONCLUSION： EWN treatment can reduce fatigue-induced increase of serum TNF-alpha， ACTH and corticosterone levels， and raise motor ability， suggesting a favorable regulation of HPA axis and immune function after EWN and improvement of fatigue in fatigue