Miracle-dz/UniFAR-FTUs huggingface dataset:
On efficiency of mean–variance based portfolio selection in defined contribution pension schemes

We consider the portfolio selection problem in the accumulation phase of a defined contribution (DC) pension scheme. We solve the mean–variance portfolio selection problem using the embedding technique pioneered by Zhou and Li [Appl. Math. Optimiz. , 2000, 42, 19–33] and show that it is equivalent to a target-based optimization problem, consisting of the minimization of a quadratic loss function. We support the use of the target-based approach in DC pension funds for three reasons. Firstly, it transforms the difficult problem of selecting the individual's risk-aversion coefficient into the easier task of choosing an appropriate target. Secondly, it is intuitive, flexible and adaptable to the member's needs and preferences. Thirdly, it produces final portfolios that are efficient in the mean–variance setting. We address the issue of the comparison between an efficient portfolio and a portfolio that is optimal according to the more general criterion of maximization of the expected utility (EU). The two natural notions of Variance Inefficiency and Mean Inefficiency are introduced, which measure the distance of an optimal inefficient portfolio from an efficient one, focusing on their variance and on their expected value, respectively. We illustrate the general procedure for finding the mean–variance inefficiency for the HARA class of utility functions, and then focus on the popular classes of CARA and CRRA utility functions. In these cases we prove the intuitive but non-trivial result that the mean–variance inefficiency decreases with the risk aversion of the individual and increases with the time horizon and the Sharpe ratio of the risky asset. As a by-product we prove that the CARA and CRRA optimal portfolios are not mean–variance efficient. Numerical investigations stress the impact of the time horizon on extent of the mean–variance inefficiency of CARA and CRRA utility functions. While at the instantaneous level EU optimality and efficiency coincide (see Merton [J. Econ. Theory, 1971, 3, 373–413]), we find that, for short durations, they do not differ significantly. However, for longer durations, which are typical for pension funds, the extent of the inefficiency turns out to be remarkable and should be taken into account by pension fund investment managers seeking appropriate rules for portfolio selection. Indeed, we see this result as a fourth reason for supporting the use of the target-based approach in DC pension schemes.
Conservation Narratives in Costa Rica: Conflict and Co‐existence

This article examines narratives about nature conservation in Costa Rica, specifically those related to wildlife and biodiversity, and their evolution with the growth of tourism and bioprospecting industries. It outlines a traditional conservation narrative and two streams of an emerging counter-narrative, and discusses problems and prospects for each in contemporary Costa Rica. The use of narrative and counter-narrative follows Roe (1991, 1995), Fairhead and Leach (1995), and Leach and Mearns (1996). The article focuses particularly on the ways in which the narratives are increasingly drawing on, informing, and sometimes conflicting with one another; it is based on the author’s research undertaken in various protected areas in Costa Rica since 1994 and on research published by others.
Reduced nicotinamide adenine dinucleotide phosphate oxidase 2 plays a key role in stellate cell activation and liver fibrogenesis in vivo.

BACKGROUND & AIMS Hepatocyte apoptosis and activation of hepatic stellate cells (HSC) are critical events in fibrogenesis. We previously demonstrated that phagocytosis of apoptotic hepatocytes by HSC is profibrogenic. Based on this, as well as the observation that reduced nicotinamide adenine dinucleotide phosphate oxidase (NADPH) oxidase induction is central to fibrogenesis, our aim was to study the phagocytic NADPH oxidase NOX2. METHODS An in vivo phagocytosis model was developed by injecting wild type (wt) or NOX2(-/-) mice with lentiviral-green fluorescence protein (GFP) containing a hepatocyte-specific promoter, and adeno-tumor necrosis factor-related apoptosis-inducing ligand (ad-TRAIL). Fibrosis was evaluated in bile duct ligated (BDL) wt and NOX2(-/-) mice with or without gadolinium treatment. NOX2 expression was studied in human liver samples and in HSC isolated from fibrotic livers. The fibrogenic activity of NOX2 was assessed by collagen reporter assays. RESULTS In the phagocytosis model, engulfment of GFP-labeled apoptotic bodies was seen, and the expression of α-smooth muscle actin (α-SMA) and collagen I increased significantly in the wt but not in the NOX2(-/-) mice. Inhibiting apoptosis decreased the profibrogenic response. NOX2(-/-) animals exhibited significantly less fibrosis following BDL. Inactivating macrophages in wt BDL mice did not lower collagen production to the level observed in NOX2(-/-) mice, suggesting that NOX2-expressing HSC are important in fibrogenesis. NOX2 was up-regulated in HSC from fibrotic livers, and phagocytosis-induced NOX2 expression and activity were demonstrated. Based on reporter assays, production of NOX2-mediated reactive oxygen species directly induced collagen promoter activity in HSC. CONCLUSIONS Apoptosis and phagocytosis of hepatocytes directly induce HSC activation and initiation of fibrosis. NOX2, the phagocytic NADPH oxidase, plays a key role in this process and in liver fibrogenesis in vivo.
University of Alberta Genetic adaptation of aspen populations to spring risk environments: a novel remote sensing approach

This study investigates geographic patterns of gene tic variation in aspen spring phenology to understanding how tree population adap ts to climatically risk environments. These finding suggest rules to guide seed transfer between regions. I use a classical common garden experiment to revea l genetic differences among populations from western Canada and Minnesota, and present a novel method to seamlessly map the heatsum required for remotely se nsed green-up. Both approaches reveal two major geographic patterns: no rthern and high elevation aspen populations break bud earlier than sources fr om the boreal plains, and late budbreak is strongly associated with the driest win er and spring environments. This suggests selection pressures for late budbreak due to both frost and drought risks in early spring, and we therefore caution aga inst transfer of seed to droughtprone regions of the boreal plains. Although such transfers have been shown to increase plantation productivity in shortte m tests, non-local planting material may be susceptible to exceptional spring d roughts.
Corporate liquidity: evidence from the United Kingdom life insurance industry

This study analyses the extent and effects of macroeconomic and firm-specific factors on insurer liquidity in the context of UK life companies with panel data for the period 1985 to 2002. Ordinary least squares regressions, static and dynamic panel data models are estimated. Econometric tests indicate a preference for the random effects estimation procedure over other alternatives. The results indicate that the life office liquidity is an increasing function of equity returns, free asset ratio, termination rate, and claims ratio and a decreasing function of pension reserves-to-total reserves. Also, it is found that mutual companies tend to hold more liquid assets than do stock companies.
Towards a natural gesture interface: LDA-based gesture separability

AbstractThe goal of this paper is to analyse a method of validating a subset of gesturesto be used as elements of a HCI interface. We investigate the applicability ofLDA for gesture data dimensionality reduction. An Gesture mutual separabilityanalysis of a diverse dataset of 22 natural gestures captured with two motion-capture devices is provided. Fisher criterion is used to produce measures of classseparability and class overlap.Keywords: LDA, gestures, separability, HCI, motion-capture1. IntroductionWith a widespread use of motion-tracking devices, both traditional e.g. com-puter mouse and new Nintendo Wii Remote TM , cell phone accelerometer ar-rays, the importance of motion-based interfaces in Human-Computer Interac-tion (HCI) systems became unquestionable. The commercial success of simplemotion-capture devices led to the development of more robust and versatileacquisition systems, both mechanical e.g. Cyberglove Systems Cyberglove TM ,Measurand ShapeWrap TM , DGTech DG5VHand and optical e.g. MicrosoftKinect
Real time temporal segmentation of MPEG video

One of the main customers of video annotation applications are TV broadcasters, and one of their key requirements is on-line annotation of received digital channels in order to offer dynamic value-added content-based services. For this purpose, apart from high levels of success in video temporal segmentation - a highly resource-consuming task previous to video annotation - a faster than real-time performance is also crucial. The paper describes a video temporal segmentation module able to detect abrupt transitions and all types of gradual transitions in real time, with levels of recall and precision not previously reached for so large and varied a set of video sequences.
Impact of wedge-shaped design for building bottlenecks on evacuation time for efficiency optimization

In order to ensure people’s safety during the evacuation process in an emergency, it is important to improve evacuation efficiency, particularly to reduce the egress time. In the present study, a wedge-shaped design for building bottleneck spaces, including exits, passageways, and joints of intersection, is proposed and described. Furthermore, through numerical simulation using a social force model, the impact of the wedge design on the evacuation time of occupants is investigated. It can be found that the evacuation time is reduced with the wedge design compared to a rectangular design under the same conditions. The effects of the short-side length and angle of wedge (β) are also examined. For the different short-side lengths studied (0.8 and 1.0 m), the mean difference in the evacuation time-saving rate increases at a relatively steady rate with the increase in the long-side length. In addition, simulation results indicate the maximum evacuation time-saving rate appears when β ranges between 45° and 53.13°. It is hoped that the results will serve as basic reference to improve relevant engineering construction of building spaces and management of emergency evacuations.
China's New Assertiveness in the South China Sea

China's new assertiveness in the South China Sea has arisen from the growth of its military power, its ‘triumphalism’ in the wake of the Western financial crisis and its heightened nationalism. The other littoral states of the South China Sea have been troubled by the opacity of Chinese politics and of the process of military decision-making amid a proliferation of apparently separately controlled maritime forces. The more active role being played by the United States in the region, in part as a response to Chinese activism, has troubled Beijing. While most of the ASEAN states have welcomed America as a hedge against growing Chinese power, their economies have become increasingly dependent upon China and they don't want to be a party to any potential conflict between these two giants. The problem is that there is no apparent resolution to what the Chinese call, in effect, these ‘indisputable disputes’.
Evaluation of the angiotensin II receptor AT1B gene as a candidate gene for blood pressure

Objective To answer two specific questions concerning the possible role played by the angiotensin II receptor AT1 B (AT1 B) locus in genetic hypertension. First, do alleles at the AT1 B locus cosegregate with blood pressure in F2 populations in the rat and, if so, is this due to AT1 B or a closely linked quantitative trait locus (QTL)? Secondly, are there any significant nucleotide differences between the coding regions of the AT1B gene of the inbred Dahl salt-sensitive (SS/Jr) strain and various control strains, or between the Lyon hypertensive (LH) strain the Lyon normotensive (LN) strain? Design The first objective was achieved by studying several F2 rat populations and by analyzing DNA markers around the AT1B locus. The second objective was accomplished by amplifying the AT1B coding regions by polymerase chain reaction from the genomic DNA, and by sequencing the relevant coding regions of the AT1B genes. Results: In two F2 populations involving the SS/Jr rat, AT1 B cosegregated only weakly with systolic blood pressure. Also, nucleotide differences resulting in conservative changes in three amino acids were detected between the coding region of the SS/Jr AT1B allele and the AT1B alleles of the several control strains. No nucleotide differences were found in the coding regions of the AT1B alleles between the LH and LN strains. Conclusion: There appeared to be a QTL which had a minor effect on blood pressure, located near the AT1B locus on rat chromosome 2. However, the AT1 B gene itself is not supported as the candidate gene for causing blood pressure differences, because no nucleotide changes in the coding region that were functionally meaningful or concordant with the cosegregation analysis were detected.
Test of the Bank Lending Channel for a BRICS Country

Based on a simultaneous-equation model of loan demand and loan supply and applying the three-stage least squares method, this paper finds that loan demand is negatively affected by the lending rate and positively associated with manufacturing production and the inflation rate and that loan supply is positively influenced by the lending rate, bank deposits, and the nominal effective exchange rate and negatively affected by the government bond yield and the policy rate. The bank lending channel is confirmed for South Africa as expansionary monetary policy such as a lower policy rate or open market purchases of government bonds would reduce the cost of borrowing by banks and increase bank deposits/reserves.
Transferable Skills, Job Matching, and the Inefficiency of the 'Natural' Rate of Unemployment

The idea of the 'natural' rate of unemployment has been with us since Friedman (i 968). This can be interpreted simply as an assertion of the long-run homogeneity of the Walrasian or flexible-price IS-LM system in prices (see e.g. Sargent (I979), p. 325). Over the last ten years, however, attempts have been made to model the 'natural' rate explicitly, following the original Friedman/Phelps idea that it could be thought of as the equilibrium rate of unemployment in a search framework. Although the main focus of attention, especially on the empirical side, has been on the determinants of the equilibrium rate and changes in this rate (see Johnson and Layard, I 984) it was soon recognised that in a search environment the equilibrium rate may not be efficient. This point was made by Tobin (I972), among others, who said: 'The external effects are the familiar ones of congestion theory. A worker deciding to join a queue or stay in one considers the probabilities of getting a job, but not the effects of his decision on the probabilities that others face. external effects also occur in the decisions of employers whether to fill a vacancy with the applicant at hand or to wait for someone more qualified. ' Recent papers by Diamond and Pissarides (see Diamond, I 98 I, I 982; Pissarides, I983, I984) have attempted to model these external effects in a stochastic matching model that can be described briefly as follows. There are a number of jobs and workers, who are paired by a stochastic matching process. The number of jobs (or workers) may be fixed or determined by free-entry conditions. Once a job and worker are paired, the productivity of the match is determined by random draw, and the partners must decide whether to accept or reject it. There are potentially three margins of decision-making in this type of model; the decision to enter (or exit) the market, the choice of lowest acceptable (reservation) productivity, and the choice of search or advertising intensity. It has been shown that individual decision-making at each of these three margins may be socially inefficient. What these inefficiencies have in common, as Pissarides (i 983) makes clear, is that they are all due to external effects that work through the matching technology; that is, when individuals choose to enter a market, accept a match, or search more intensively, they ignore the impact of their decisions on the matching probabilities of other agents in the market. One important limitation of the Diamond-Pissarides model is that both firms and workers are assumed homogeneous. We show in this paper that if this
Spinal cord lesions of progressive multifocal leukoencephalopathy in an acquired immunodeficiency syndrome patient

Progressive multifocal leukoencephalopathy (PML) is a deadly demyelinating disease of the central nervous system, which occurs in immunosuppressed individuals. This disease is caused by a reactivation of the polyomavirus JC (JCV). Clinical presentation can be variable from patient to patient as lesions can occur anywhere in the CNS white matter; however, they appear to spare the optic nerves and the spinal cord. The authors present a case of PML in the setting of acquired immunodeficiency syndrome (AIDS) who developed PML lesions in the spinal cord, discovered during the postmortem examination. This finding is significant because PML has recently been diagnosed in patients with multiple sclerosis (MS) treated with the novel immunomodulatory medication natalizumab. Indeed, spinal cord lesions are frequent in MS. Therefore clinicians should be aware that in addition to the brain, PML may also affect the spinal cord white matter.
Moderating effect of firm size on the relationship between voluntary employer changes and salary attainment

This study presents a meaningful moderator, a fundamental characteristic of employers – their size, to unravel the inconsistencies regarding the relationship between the workers’ voluntary employer changes and salary attainment in previous studies. Results indicate that voluntary employer changes did not predict salary attainment in large firms, whereas a positive effect was found to be stronger in medium than in small firms. Also presented herein are several explanations for the moderating property of firm size.
Older people's participation in disability benefits: targeting, timing and financial wellbeing

This paper evaluates the effectiveness of disability benefits for the elderly. Using seventeen waves of panel data, it first analyses the extent to which receipt is responsive to changes in disability status. Second, it investigates the extent of delays in first receipt. Third, it compares later outcomes of recipients and non-recipients, accounting for selection into the program. Results indicate that entry is highly responsive to previous changes in disability, and that the program enhances persistently recipientsâ€™ financial wellbeing. However, considerable delays in receipt are also found. Besides, the evidence of characteristics unrelated to eligibility influencing the assignment mechanism raises horizontal equity concerns.
Peer reviews in the fight against terrorism: A hidden dimension of European security governance

This article analyses EU peer reviews in the fight against terrorism, which constitute a significant and previously unstudied instrument of European security governance. The first part reviews some general features of security governance and outlines two analytical perspectives to assess the effect of peer reviews in this context, namely compliance and learning. The second part surveys the historical development and substantive impact of the EU’s peer reviews on the fight against terrorism. Although the first peer review after the attacks of 9/11 was slow to unfold, it eventually came to be regarded as a highly successful exercise that improved mutual trust and the coherence of the European fight against terrorism. It was therefore followed by a second peer review on consequence management in response to terrorist attacks. From a critical perspective, the article argues that the impact of these peer reviews could be doubted from both compliance and learning perspectives, as monitoring and flanking measures have remained too weak. The conclusions raise further avenues for research on peer reviews that are a regular feature of EU security governance.
A point mutation in the human cytomegalovirus DNA polymerase gene confers resistance to ganciclovir and phosphonylmethoxyalkyl derivatives

Ganciclovir-resistant mutant 759rD100 derived from human cytomegalovirus strain AD169 contains two resistance mutations, one of which is in the UL97 gene and results in decreased ganciclovir phosphorylation in infected cells [V. Sullivan, C. L. Talarico, S. C. Stanat, M. Davis, D. M. Coen, and K. K. Biron, Nature (London) 358:162-164, 1992]. In the present study, we mapped the second mutation to a 4.1-kb DNA fragment containing the DNA polymerase gene and showed that it confers ganciclovir resistance without impairing phosphorylation. Sequence analysis of the 4.1-kb region revealed a single nucleotide change that resulted in a glycine-to-alanine substitution at position 987 within conserved region V of the DNA polymerase. Recombinant viruses constructed to contain the DNA polymerase mutation but not the phosphorylation defect displayed intermediate resistance (4- to 6-fold) to ganciclovir relative to the original mutant 759rD100 (22-fold); the recombinant viruses also displayed resistance to ganciclovir cyclic phosphate (7-fold), 1-(dihydroxy-2-propoxymethyl)-cytosine (12-fold), and the phosphonylmethoxyalkyl derivatives (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)adenine and (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine (8- to 10-fold). However, the recombinant viruses remained susceptible to certain related compounds. These results imply that the human cytomegalovirus DNA polymerase is a selective target for the antiviral activities of ganciclovir, certain of its derivatives and phosphonomethoxyalkyl derivatives; support a role for region V in substrate recognition; and suggest the possibility of clinical resistance of human cytomegalovirus to these compounds because of polymerase mutations.
Sink Metabolism in Tomato Fruit : III. Analysis of Carbohydrate Assimilation in a Wild Species.

Carbohydrate composition and key enzymes involved in carbohydrate metabolism were assayed throughout development of Lycopersicon esculentum and L. chmielewskii fruit. Translocation and assimilation of asymmetric sucrose and total soluble solids content was also determined in both species. The data showed that L. chmielewskii accumulated less starch than L. esculentum, and this was related to a lower level of ADPglucose pyrophosphorylase and a higher level of phosphorylase in L. chmielewskii. L. chmielewskii accumulated sucrose throughout fruit development rather than glucose and fructose which were accumulated by L. esculentum. A low level of invertase and nondetectable levels of sucrose synthase were associated with the high level of sucrose in L. chmielewskii. Translocation and assimilation of asymmetrically labeled sucrose indicated that sucrose accumulated in L. chmielewskii fruit was imported and stored directly in the fruit without intervening metabolism along the translocation path. In contrast, the relatively low level of radioactive sucrose found in L. esculentum fruit appeared to arise from hydrolysis and resynthesis of sucrose. The possible relationship between the level of soluble solids and differences in carbohydrate metabolism in sink tissue of the two species is discussed.