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The principal seeks a portfolio manager to manage funds. The principal uses a tracking-error constraint that restricts the portfolio’s volatility. Without the constraint, the manager may increase the portfolio return by adding high-variance assets. Tests assume that the benchmark is the value-weighted market portfolio less the risk-free rate (MKT). Tests then add the Fama and French four long–short portfolios to test if they can increase return without a large increase in the portfolio variance. SMB (Small Minus Big) is long in small stocks and short in big stocks and picks up the small-firm premium. HML (High Minus Low) is long in high book-to-market stocks and short in low book-to-market stocks and picks up the value premium. WML (Winners Minus Losers) is long in past winners and short in past losers and picks up the momentum premium. Tests find that SMB adds tracking error and small returns, HML adds tracking error and large returns, and WML adds modest tracking error and large returns. WML requires he...

The synchronization phase of a code division multiple access communication system might pose a limitation on the performance of the system, since unlike other communication systems it is required to obtain the state (i.e., sequence phase) of a linear feedback shift register (LFSR). Usually the state is obtained by using a brute force exhaustive search over all possibilities, which might be a computationally demanding task. In this paper, we suggest a new method for LFSR sequence phase acquisition. Our method is suitable for practical systems in which an unknown frequency drift may be present. Simulation results for the IS-95/CDMA-2000 standard show a dramatic reduction in the time required to acquire synchronization when using the new algorithm compared to the standard synchronization method.

OBJECTIVE: To describe a case of azathioprine hypersensitivity in a patient with ulcerative colitis. CASE SUMMARY: A 40-year-old white man with ulcerative colitis, treated with chronic mesalamine and occasional steroids, was admitted to the hospital with a 3-day history of fever, nausea, vomiting, and a rash. Fourteen days prior to admission, the patient had been started on azathioprine for ulcerative colitis. Upon admission, azathioprine therapy was temporarily withheld, resulting in resolution of his signs and symptoms. Symptoms returned when azathioprine was restarted. It was decided that these signs and symptoms were most likely caused by azathioprine hypersensitivity, and the agent was discontinued. DISCUSSION: To our knowledge, this is the first reported case of azathioprine hypersensitivity in a patient with ulcerative colitis. The time course and presenting signs and symptoms support the diagnosis of azathioprine hypersensitivity, as does the patient's response to rechallenge. The mechanism of this hypersensitivity reaction is unclear, but may involve the nitroimidazole portion of the azathioprine molecule. CONCLUSIONS: Azathioprine hypersensitivity often presents with signs and symptoms resembling a systemic infection such as fever, leukocytosis, and evidence of end organ dysfunction. The diagnosis of azathioprine hypersensitivity should be considered in patients who have recently either initiated or increased their dosage of azathioprine. OBJETIVO: Reportar un caso de hipersensitividad a azathioprine en un paciente con colitis ulcerativa. RESUMEN DEL CASO: Un hombre de 40 años con colitis ulcerativa tratado cronicamente con mesalamine y ocasionalmente esteroides, fue hospitalizado con un historial de 3 días con fiebre, naúsea, vómitos, e irritación en la piel. Catorce días previo a la admisión, el paciente había comenzado en azathioprine para su colitis ulcerativa. En la admisión, la azathioprine fue temporalmento descontinuada resultando en la resolución de los signos y síntomas. Los síntomas comenzaron cuando se utilizó nuevamente el azathioprine. Se decidió que estos signos y síntomas eran bien parecidos a una hipersensitividad a azathioprine y el medicamento fue descontinuado. DISCUSIÓN: Hasta donde se conoce es el primer caso reportado con hipersensitividad a azathioprine en un paciente con colitis ulcerativa. El tiempo del curso y presentación de los signos y síntomas apoyan el hallazgo así como la respuesta del paciente al ser tratado nuevamente. El mecanismo de esta hipersensitividad no está claro pero podría envolver la porción de nitromidazole de la mólecula de azathioprine. CONCLUSIONES: A menudo la hipersensitividad a azathioprine presenta los signos y síntomas parecidos en una infección sistémica como fiebre, leucosiotosis, y evidencia de disfunción en órganos terminales. El diagnóstico de hipersensitividad a azathioprine debe ser considerado en pacientes que recientemente comenzaron en el medicamento y en casos en que se les aumente la dosis de azathioprine. OBJECTIF: Rapporter un cas d'hypersensibilité à l'azathioprine chez un patient atteint de colite ulcéreuse. RÉSUMÉ DU CAS: Un homme de 40 ans attéint de colite ulcéreuse et traité de façon chronique avec de la mésalamine et occasionnellement avec des corticostéroïdes a été admis à l'hôpital pour fièvre, nausées, vomissements, et rash persistant depuis 3 jours. Quatorze jours avant son admission, un traitement à l'azathioprine avait été débuté pour sa colite ulcéreuse. À l'admission, l'azathioprine a été temporairement cessée, ce qui a permis la résolution des signes et symptômes. Les symptômes sont réapparus lorsque l'azathioprine a été reprise. Les signes et symptômes présentes par le patient étant compatibles avec une réaction d'hypersensibilité à l'azathioprine, il fut décidé de cesser définitivement l'azathioprine. DISCUSSION: Selon les auteurs, il s'agirait du premier cas d'hypersensibilité à l'azathioprine rapporté chez un patient atteint de colite ulcéreuse. l'évolution de la réaction dans le temps, les signes et symptômes de même que la réapparition des symptômes lors de la réadministration du médicament tendent à incriminer l'azathioprine. Le mécanisme de cette réaction d'hypersensibilité n'est pas clairement défini mais pourrait impliquer la portion nitroimidazole de la molécule d'azathioprine. CONCLUSIONS: L'hypersensibilité à l'azathioprine se manifeste fréquemment par des signes et symptômes ressemblant à une infection systémique tels que fièvre, leucocytose, et évidence de dysfonction d'un organe. Le diagnostic d'hypersensibilité à l'azathioprine devrait être considéré chez les patients qui reçoivent depuis peu de l'azathioprine ou chez qui la dose d'azathioprine a été augmentée.

This paper investigates a transform that provides diversity to words of symbols transmitted over fading channels. This diversity transform (DRT) does not alter the distance between the input words nor the bandwidth or the information rate. The transform is based on an orthonormal transform and thus increases the channel alphabet. A considerable diversity gain is achieved over Rayleigh fading channel with perfect channel state information (CSI) and interleaving. The transform performances are evaluated both analytically and by simulation, and optimal transforms are determined for specific channels. Finally, a simple nonoptimal decoding scheme is developed, which provides a powerful and practical technique to transfer information over fading channels with or without coding.

The distinct effects of cytokines on cellular growth and differentiation suggest that specific signaling pathways mediate these diverse biological activities. Fibroblast growth factors (FGFs) are well-established inhibitors of skeletal muscle differentiation and may operate via activation of specific signaling pathways distinct from recently identified mitogen signaling pathways. We examined whether platelet-derived growth factor (PDGF)-activated signaling pathways are sufficient to mediate FGF-dependent repression of myogenesis by introducing the PDGF beta receptor into a mouse skeletal muscle cell line. Addition of PDGF-BB to cells expressing the PDGF beta receptor activated the PDGF beta receptor tyrosine kinase, stimulated mitogen-activated protein (MAP) kinase, and increased the steady-state levels of junB and c-fos mRNAs. Despite the activation of these intracellular signaling molecules, PDGF beta receptor activation elicited no detectable effect on cell proliferation or differentiation. In contrast to PDGF-BB, addition of FGF-2 to myoblasts activated signaling pathways that resulted in DNA synthesis and repression of differentiation. Because of the low number of endogenous FGF receptors expressed, FGF-stimulated signaling events, including tyrosine phosphorylation and activation of MAP kinase, could be detected only in cells expressing higher levels of a transfected FGF receptor cDNA. As the PDGF beta receptor- and FGF receptor-stimulated signaling pathways yield different biological responses in these skeletal muscle cells, we hypothesize that FGF-mediated repression of skeletal muscle differentiation activates signaling pathways distinct from those activated by the PDGF beta receptor. Activation of PDGF beta receptor tyrosine kinase activity, stimulation of MAP kinase, and upregulation of immediate-early gene expression are not sufficient to repress skeletal muscle differentiation.

Instruction scheduling consists of the rearrangement of transformation of program statements, usually at the intermediate language or assembly code level, in order to reduce possible run-time delays between instructions. Such transformations must preserve data dependency and are subject to other constraints. Highly optimizing compilers employing instruction-scheduling techniques have proven to be effective in improving the performance of pipeline processors. Considerable attention has been given to scheduling code within the scope of basic blocks, i.e., straight-line sections of code. In this paper the authors present techniques for scheduling beyond basic blocks. This allows a further reduction in run-time delays such as those due, e.g., to branches and loops, enabling the exploiting of pipeline architectures which would not otherwise be possible.

The entry of human cytomegalovirus (HCMV) into biologically relevant epithelial and endothelial cells involves endocytosis followed by low-pH-dependent fusion. This entry pathway is facilitated by the HCMV UL128, UL130, and UL131 proteins, which form one or more complexes with the virion envelope glycoprotein gH/gL. gH/gL/UL128-131 complexes appear to be distinct from the gH/gL/gO complex, which likely facilitates entry into fibroblasts. In order to better understand the assembly and protein-protein interactions of gH/gL/UL128-131 complexes, we generated HCMV mutants lacking UL128-131 proteins and nonreplicating adenovirus vectors expressing gH, gL, UL128, UL130, and UL131. Our results demonstrate that UL128, UL130, and UL131 can each independently assemble onto gH/gL scaffolds. However, the binding of individual UL128-131 proteins onto gH/gL can significantly affect the binding of other proteins; for example, UL128 increased the binding of both UL130 and UL131 to gH/gL. Direct interactions between gH/UL130, UL130/UL131, gL/UL128, and UL128/UL130 were also observed. The export of gH/gL complexes from the endoplasmic reticulum (ER) to the Golgi apparatus and cell surface was dramatically increased when all of UL128, UL130, and UL131 were coexpressed with gH/gL (with or without gO expression). Incorporation of gH/gL complexes into the virion envelope requires transport beyond the ER. Thus, we concluded that UL128, UL130, and UL131 must all bind simultaneously onto gH/gL for the production of complexes that can function in entry into epithelial and endothelial cells.

Herpes simplex virus (HSV) spreads rapidly and efficiently within epithelial and neuronal tissues. The HSV glycoprotein heterodimer gE/gI plays a critical role in promoting cell-to-cell spread but does not obviously function during entry of extracellular virus into cells. Thus, gE/gI is an important molecular handle on the poorly understood process of cell-to-cell spread. There was previous evidence that the large extracellular (ET) domains of gE/gI might be important in cell-to-cell spread. First, gE/gI extensively accumulates at cell junctions, consistent with being tethered there. Second, expression of gE/gI in trans interfered with HSV spread between epithelial cells. To directly test whether the gE ET domain was necessary for gE/gI to promote virus spread, a panel of gE mutants with small insertions in the ET domain was constructed. Cell-to-cell spread was reduced when insertions were made within either of two regions, residues 256 to 291 or 348 to 380. There was a strong correlation between loss of cell-to-cell spread function and binding of immunoglobulin. gE ET domain mutants 277, 291, and 348 bound gI, produced mature forms of gE that reached the cell surface, and were incorporated into virions yet produced plaques similar to gE null mutants. Moreover, all three mutants were highly restricted in spread within the corneal epithelium, in the case of mutant 277 to only 4 to 6% of the number of cells compared with wild-type HSV. Therefore, the ET domain of gE is indispensable for efficient cell-to-cell spread. These observations are consistent with our working hypothesis that gE/gI can bind extracellular ligands, so-called gE/gI receptors that are concentrated at epithelial cell junctions. This fits with similarities in structure and function of gE/gI and gD, which is a receptor binding protein.

The generalized cut-off rate of time- and frequency-selective fading channels is used to the optimal signalling rate and code rate. Two modulation types, M-ary frequency shift keying (MFSK) and M-ary differential phase shift keying (MDPSK) with soft decoding are investigated as well as three dispersive channels. The guard time effect, employed to combat multipath, is evaluated for frequency-selective channels and the optimal combination of signalling rate, code rate and guard time is presented. Special attention is given to CCIR (International Radio Consultative Committee) HF channel models.

Many modern processors seek to boost their performance by exploiting instruction level parallelism. For these computers the compiler must generate the code that takes full advantage of machine resources. The IBM RISC System/6000 is a superscalar processor, capable of executing fixed point and floating point instructions in parallel. In addition it introduced a new pipelining concept of a separate branch unit, aiming to achieve zero-cost branches. We review a set of instruction scheduling techniques which were implemented in the IBM XL compiler to fully exploit the parallel/pipelined features of this machine. We evaluated these optimizations on the SPEC benchmarks. Performance improvements of 18% are achieved at the expense of a 19% increase in compile time. This study provides new insights into the branch unit in the RTSC System/6000, and shows interesting trade-offs between the run time performance and compile time.

The natural history of infection with hepatitis E virus (HEV) in patients with chronic liver disease (CLD) is not well described. Our study aims to document the presentation, course and outcome of HEV superinfection in patients with CLD.Over an 18-month period, ten patients with CLD were diagnosed to have HEV superinfection by detection of anti-HEV IgM antibodies in a setting of acute worsening. These patients were tested for HBsAg, IgM anti-HBc, anti-hepatitis C virus antibodies and IgM anti-hepatitis A virus antibodies, and were followed-up.The etiology of underlying CLD in the 10 patients (9 men; mean [SD] age 42.4 [10.3] years) was alcohol in five patients, hepatitis B in two, hepatitis C in one and cryptogenic in two. Seven patients presented for the first time with recent-onset liver decompensation (median duration 27 days, range 7-45). All 10 had ascites and 7 had hepatic encephalopathy. Four patients developed renal failure during the course of illness. The median (range) bilirubin, ALT and albumin levels at presentation were 18.6 (4.9-32.6) mg/dL, 105 (28-6610) IU/L and 32 (29-41) g/L, respectively. At 8 weeks, only one patient had normalization of serum bilirubin or ALT levels. Three patients (30%) died, including two of renal failure and one of massive upper GI bleed.Superinfection with HEV in patients with CLD causes severe liver decompensation, which is frequently complicated with hepatic encephalopathy and renal failure. Acute hepatitis E in these patients has a protracted course with high morbidity and mortality.

The paper presents an efficient implementation of the baseband functions for the Japan Digital Cellular (JDC) handheld (or mobile) unit. This three ICs implementation includes a digital signal processor (DSP), an application specific IC (ASIC) and an off-the-shelf voice codec. Design considerations, as well as performances are presented, for various baseband functions that include the modem and the voice coder. >

This paper studies the effect of currencydevaluation on aggregate output level in South- East Asian countries usingpanel data from Thailand, Malaysia, Indonesia and the Philippines for a periodfrom 1980 to 2010. An empirical modelthat includes monetary, fiscal and exchange rate variables is developed. Two versions of the model, one with realexchange rate and another with nominal exchange rate and foreign-to-domesticprice ratio are estimated. An errorcorrection model is developed and the time series properties of the panel dataare diagnosed before estimating the model.The estimated results suggest that currency devaluations are contractionaryin the short run and the intermediate run and this contractionary effect comesfrom the change in nominal exchange rate and not from the change in foreign-to-domesticprice ratio.

This paper examines the effect of Real Exchange Rate Volatility (RERVOL) on the Foreign Direct Investment (FDI) inflow in Bangladesh, India, Pakistan and Sri Lanka. A model that includes exchange rate volatility with other determinants of FDI is developed. Annual time series data from 1976–2009 is used for India, Pakistan and Sri Lanka. In case of Bangladesh because of the data limitation only data series from 1986–2009 is used. A panel data from these four countries for a period of 1986–2009 is also constructed. Before estimating the model the time series properties of the data are diagnosed and an error correction model is developed. The estimated results show an inconclusive relationship between the exchange rate volatility and the FDI.

Instruction scheduling algorithms are used in compilers to reduce run-time delays for the compiled code by the reordering or transformation of program statements, usually at the intermediate language or assembly code level. Considerable research has been carried out on scheduling code within the scope of basic blocks, i.e., straight line sections of code, and very effective basic block schedulers are now included in most modern compilers and especially for pipeline processors. In previous work Golumbic and Rainis: IBM J. Res. Dev., Vol. 34, pp.93–97, 1990, we presented code replication techniques for scheduling beyond the scope of basic blocks that provide reasonable improvements of running time of the compiled code, but which still leaves room for further improvement. In this article we present a new method for scheduling beyond basic blocks called SHACOOF. This new technique takes advantage of a conventional, high quality basic block scheduler by first suppressing selected subsequences of instructions and then scheduling the modified sequence of instructions using the basic block scheduler. A candidate subsequence for suppression can be found by identifying a region of a program control flow graph, called an S-region, which has a unique entry and a unique exit and meets predetermined criteria. This enables scheduling of a sequence of instructions beyond basic block boundaries, with only minimal changes to an existing compiler, by identifying beneficial opportunities to cover delays that would otherwise have been beyond its scope.

The full-length human estrogen receptor (hER) as well as two overlapping peptides of hER were overproduced in Escherichia coli JM109 cells, using the inducible pIC vector system. The N-terminal receptor peptide contains the DNA-binding domain as well as the hinge region, whereas the C-terminal peptide contains the same hinge region and the hormone-binding domain. Typically, 1-6 mg of estrogen receptor (ER) peptides can be recovered from 1 L E. coli cell cultures. The majority of the overexpressed proteins are found in inclusion bodies, which allow the isolation of ER peptides in high yields and of 50-80% purity. Induction for short time periods at 10 microM inducer yielded up to 50% of the ER peptides in soluble form with full biological activity. Both the intact receptor and the C-terminal fragment specifically bound estrogens and antiestrogens, whereas ER peptides that contained the DNA-binding domain were retained on a DNA-agarose resin.

The generalized cutoff rate of time- and frequency-selective fading channels is evaluated for M-ary frequency-shift keying (MFSK) and M-ary differential phase-shift keying (MDPSK) modulation with soft decoding. The optimal signaling rate and code rate for dispersive channels are evaluated. The guard time effect, is used in multipath spread channels, is evaluated for frequency-selective channels, and the optimal combination of signaling rate, code rate, and guard time is presented. Special attention is given to CCIR (International Radio Consultative Committee) HF channel models. >

The cut-off rate for a frequency selective fading and noise varying HF channel is evaluated. This novel result is used to evaluate the optimal signalling rates for noncoherent BFSK and differentially coherent DPSK modems. The guard time effect, usually employed in multipath spread channels, is considered and the optimal combination of signalling rate and guard time is evaluated.