34 research outputs found
Explaining Import Variety and Quality: The Role of the Income Distribution
We examine a generalized version of Flam and Helpman’s (1987) model of vertical differentiation that maps cross-country differences in income distributions to variations in import variety and price distributions. The theoretical predictions are examined and confirmed using micro data on income from the Luxemburg Income Study for 30 countries over 20 years. The pairs of importers whose income distributions look more similar have more export partners in common and more similar import price distributions. Similarly, the importers whose income distributions look more like the world buy from more exporters and have import price distributions that look more like the world.
Hepatitis C Virus Core Protein Inhibits Interleukin 12 and Nitric Oxide Production from Activated Macrophages
AbstractA characteristic feature of hepatitis C virus (HCV) infection is a high frequency of persistence and the progression to chronic liver diseases. Recent data suggest that prevalent T helper (Th) 2 immunity as well as weak HCV-specific T-cell response is associated with viral persistence. Here, we showed that the production of interleukin 12 (IL-12) and nitric oxide (NO) that is critical for the induction of Th1 and innate immunity, but not that of tumor necrosis factor α (TNF-α), was significantly suppressed in both HCV core-expressing macrophage cell lines and mouse peritoneal macrophages treated with recombinant core protein. In addition, IL-12 p40 promoter activity was repressed by the presence of HCV core in macrophages stimulated with lipopolysaccharride (LPS) following IFN-γ treatment, indicating that IL-12 production may be downregulated at the transcriptional level. We also found that proliferation of T cells and IFN-γ production in mixed lymphocyte reactions (MLR) with core-expressing cells were inhibited. Taken together, our results suggest that HCV core protein could play roles in suppressing the induction of Th1 immunity through inhibition of IL-12 and NO production
Determination of Thyroid Volume by Ultrasonography among Schoolchildren in Philippines
Objective. Iodine deficiency is defined by the goiter and the urinary iodine concentration. However, a lack of local thyroid volume reference data resulted in the vague definition of goiter, especially in school-aged children. The aim of this paper was to determine the thyroid volumes by ultrasonography in schoolchildren aged 6 to 12 years living in Cagayan areas in Philippine. Methods. Cross-sectional thyroid ultrasonographic data of 158 schoolchildren aged 6–12 years from Tuguegarao and Lagum in Cagayan valley, Philippine were used. Thyroid volumes were compared based on logistic issue and urban and rural area and compared with other previously reported data. Results. The mean values of thyroid volume in Tuguerago and Lagum were 2.99 ± 1.34 mL and 2.42 ± 0.92 mL. The thyroid size was significantly in association with age (P < 0.00), weight (P < 0.00), height (P < 0.00), and BSA (P < 0.00) by Pearson's correlation. The median thyroid volumes of schoolchildren investigated in this study were generally low compared to international reference data by age group but not by BSA. Conclusions. We propose for the first time local reference ultrasound values for thyroid volumes in 6–12 aged schoolchildren that should be used for monitoring iodine deficiency disorders
Two Korean Infants with Genetically Confirmed Congenital Nephrotic Syndrome of Finnish Type
Congenital nephrotic syndrome is defined as nephrotic syndrome which manifests in utero or during the first 3 months of life. The prototype of congenital nephrotic syndrome is congenital nephrotic syndrome of Finnish type (CNF, OMIM #602716), which is caused by loss-of-function mutations of the nephrin gene (NPHS1). There have been few clinical case reports of CNF in Korea, but none of which was confirmed by genetic study. Here, we report two children with congenital nephrotic syndrome. Genetic analysis of the NPHS1 gene revealed compound heterozygous frame-shifting mutations (c.2156_2163 delTGCACTGC causing p.L719DfsX4 and c.3250_3251insG causing p.V1084GfsX12) in one patient and a missense mutation (c.1381G>A causing p.R460Q) and a nonsense mutation (c.2442C>G causing p.Y814X) in the other patient. The nonsense mutation was novel. The clinical courses of the patients were typical of CNF. This is the first report of genetically confirmed CNF in Korea to date. The early genetic diagnosis of CNF is important for proper clinical management of the patients and precise genetic counseling of the families.This study was supported by a grant (06-2008-192-9) from Seoul National University Hospital
Natural Form of Noncytolytic Flexible Human Fc as a Long-Acting Carrier of Agonistic Ligand, Erythropoietin
Human IgG1 Fc has been widely used as a bioconjugate, but exhibits shortcomings, such as antibody- and complement-mediated cytotoxicity as well as decreased bioactivity, when applied to agonistic proteins. Here, we constructed a nonimmunogenic, noncytolytic and flexible hybrid Fc (hyFc) consisting of IgD and IgG4, and tested its function using erythropoietin (EPO) conjugate, EPO-hyFc. Despite low amino acid homology (20.5%) between IgD Fc and IgG4 Fc, EPO-hyFc retained “Y-shaped” structure and repeated intravenous administrations of EPO-hyFc into monkeys did not generate EPO-hyFc-specific antibody responses. Furthermore, EPO-hyFc could not bind to FcγR I and C1q in contrast to EPO-IgG1 Fc. In addition, EPO-hyFc exhibited better in vitro bioactivity and in vivo bioactivity in rats than EPO-IgG1 Fc, presumably due to the high flexibility of IgD. Moreover, the mean serum half-life of EPO-hyFc(H), a high sialic acid content form of EPO-hyFc, was approximately 2-fold longer than that of the heavily glycosylated EPO, darbepoetin alfa, in rats. More importantly, subcutaneous injection of EPO-hyFc(H) not only induced a significantly greater elevation of serum hemoglobin levels than darbepoetin alfa in both normal rats and cisplatin-induced anemic rats, but also displayed a delayed time to maximal serum level and twice final area-under-the-curve (AUClast). Taken together, hyFc might be a more attractive Fc conjugate for agonistic proteins/peptides than IgG1 Fc due to its capability to elongate their half-lives without inducing host effector functions and hindering bioactivity of fused molecules. Additionally, a head-to-head comparison demonstrated that hyFc-fusion strategy more effectively improved the in vivo bioactivity of EPO than the hyperglycosylation approach
Truly form-factor–free industrially scalable system integration for electronic textile architectures with multifunctional fiber devices
Funding Information: This work was supported by the European Commission (H2020, 1D-NEON, grant agreement ID: 685758). J.M.K. and L.G.O. acknowledge the support from the U.K. Research and Innovation (EPSRC, EP/P027628/1). We thank Y. Bernstein and J. Faulkner for helping with grammar check. Funding Information: Acknowledgments Funding:ThisworkwassupportedbytheEuropeanCommission(H2020,1D-NEON,grant agreementID:685758).J.M.K.andL.G.O.acknowledgethesupportfromtheU.K.Researchand Innovation(EPSRC,EP/P027628/1).W ethankY .BernsteinandJ.Faulknerforhelpingwith grammarcheck.Authorcontributions:S.L.andJ.M.K.conceivedtheproject.S.L.,L.G.O.,P .B., R.Martins,andJ.M.K.supervisedtheproject.S.L.andH.L.developedF-PD.S.L.,Y .-W .L., G.-H.A., D.-W .S., J.I.S.,andS.C.developedF-SC.C.L.F ., A.S.,R.I.,P .B., andR.Martinsdevelopedfiber transistor.S.L.,H.L.,andS.C.developedF-LED.ThefiberdeviceswereevaluatedbyS.L.,H.W .C., D.-W .S., H.L.,S.J.,S.D.H.,S.Y .B., S.Z.,W .H.-C., Y .-H.S., X.-B.F ., T .H.L., J.-W .J., andY .K. The developmentofweavingprocesswasconductedbyS.L.,H.W .C., F .M.M., P .J., andV .G.C. Thelaser interconnectionwasdevelopedbyS.L.,H.W .C., K.U.,M.E.,andM.S.Thetextiledemonstrations werecharacterizedbyS.L.,H.W .C., D.-W .S., J.Y ., S.S.,U.E.,S.N.,A.C.,A.M.,R.Momentè,J.G.,N.D., S.M.,C.-H.K.,M.L.,A.N.,D.J.,M.C.,andY .C. ThismanuscriptwaswrittenbyS.L.andJ.M.K.and reviewed by H.W .C., D.-W .S., M.C.,L.G.O., P .B., E.F ., and G.A.J.A. All authors discussed the results andcommentedonthemanuscript.Competinginterests:Theauthorsdeclarethattheyhave nocompetinginterests.Dataandmaterialsavailability:Alldataneededtoevaluatethe conclusionsinthepaperarepresentinthepaperand/ortheSupplementaryMaterials. Publisher Copyright: Copyright © 2023 The Authors, some rights reserved.An integrated textile electronic system is reported here, enabling a truly free form factor system via textile manufacturing integration of fiber-based electronic components. Intelligent and smart systems require freedom of form factor, unrestricted design, and unlimited scale. Initial attempts to develop conductive fibers and textile electronics failed to achieve reliable integration and performance required for industrial-scale manufacturing of technical textiles by standard weaving technologies. Here, we present a textile electronic system with functional one-dimensional devices, including fiber photodetectors (as an input device), fiber supercapacitors (as an energy storage device), fiber field-effect transistors (as an electronic driving device), and fiber quantum dot light-emitting diodes (as an output device). As a proof of concept applicable to smart homes, a textile electronic system composed of multiple functional fiber components is demonstrated, enabling luminance modulation and letter indication depending on sunlight intensity.publishersversionpublishe
Essays on product quality differentiation and international trade
Essay one examines whether a generalized version of Flam and Helpman\u27s (1987) model of vertical differentiation can reconcile three facts. One, countries import only a subset of available varieties. Two, import prices vary across exporters within narrow product categories. Three, US growth in both import variety and import price dispersion has occurred at the same time that the US income distribution has significantly widened. The generalized model maps cross-country differences in income distributions to variation in import variety and price variation. The theoretical predictions are examined and confirmed using panel data on import variety and prices, and detailed income distribution data from the Luxembourg Income Survey. Country pairs whose income distributions are growing more similar over time have growing similarity in the distribution of their import prices, and in the number of common export sources from which they buy. Essay two investigates the theoretical relationship between factor abundance and within-product specialization. To address the issue, we develop a general equilibrium model that shows the relationship between quality/quantity specialization and factor endowments. On the quality demand side, we employ a modified CES utility function to explicitly take into account the consumer\u27s preferences for quality. Quality supply side is modeled by introducing a quality differentiated intermediate goods. The model can perfectly explain the couple of recent important empirical findings (Schott 2004, Hummels and Klenow 2005). One, within-product qualities are positively correlated with capital abundance. Two, capital- (labor-) abundant countries produce higher (lower) qualities in smaller (larger) quantities within a product
Explaining Import Variety and Quality: the Role of the Income Distribution
We examine a generalized version of Flam and Helpman’s (1987) model of vertical differentiation that maps cross-country differences in income distributions to variations in import variety and price distributions. The theoretical predictions are examined and confirmed using micro data on income from the Luxemburg Income Study for 30 countries over 20 years. The pairs of importers whose income distributions look more similar have more export partners in common and more similar import price distributions. Similarly, the importers whose income distributions look more like the world buy from more exporters and have import price distributions that look more like the world
Explaining import quality: The role of the income distribution
We examine a generalized version of Flam and Helpman [Flam, H., Helpman, E., 1987. Vertical Product Differentiation and North-South Trade. American Economic Review, 77, 810-822.] in which consumption prices for quality differentiated goods are rising in household income. We provide propositions for aggregating this relationship across heterogenous households to map cross-country differences in income distributions to cross-country differences in import price distributions. The theoretical predictions are examined and confirmed using disaggregated data on prices of traded goods and micro data on household income from the Luxemburg Income Study. Country pairs with more similar income distributions have more similar import price distributions, whether similarity is measured by 1st-4th moment statistics, population and consumption shares within world income and product price quantiles, or income and price dis-similarity indices.Quality differentiation Income distribution Import price distribution Luxemburg Income Study
Explaining import quality: The role of the income distribution
We examine a generalized version of Flam and Helpman [Flam, H., Helpman, E., 1987. Vertical Product Differentiation and North-South Trade. American Economic Review, 77, 810-822.] in which consumption prices for quality differentiated goods are rising in household income. We provide propositions for aggregating this relationship across heterogenous households to map cross-country differences in income distributions to cross-country differences in import price distributions. The theoretical predictions are examined and confirmed using disaggregated data on prices of traded goods and micro data on household income from the Luxemburg Income Study. Country pairs with more similar income distributions have more similar import price distributions, whether similarity is measured by 1st-4th moment statistics, population and consumption shares within world income and product price quantiles, or income and price dis-similarity indices.Quality differentiation Income distribution Import price distribution Luxemburg Income Study