225 research outputs found
Vitellogenesis and aspects of its pituitary regulation in teleosts with emphasis on winter flounder (Pseudopleuronectes americanus)
The ovarian uptake of the homologous serum proteins vitellogenin (VG) and very high density lipoprotein II (VHDL II) (formerly peak A protein) were studied as potential yolk precursors involved in vitellogenesis in winter flounder (Pseudopleuronectes americanus). The major yolk precursor appears to be VG based on the quantity of yolk protein that recognizes the VG and VHDL II antisera by Western blotting. The rate of uptake of VG by the ovary is about three times greater than VHDL II. Internalized VG is processed into a 280,000 relative molecular mass (Mr) yolk protein (lipovitellin) that contributes to the major fraction (82%) of ovarian protein. Accumulation of VHDL II occurs in an unprocessed form and contributes to a fraction of ovarian protein representing 12% of the total. Phosvitin and a low Mr phosphoprotein were apparent but in small amounts. -- In vitro ovarian incubations done during the prespawning to early vitellogenic phases of the reproductive cycle in winter flounder showed that pituitary extract stimulates estradiol-17ÎČ (Eâ) production only during the vitellogenic phase, while induced testosterone (T) production was greatest shortly before spawning. These observations were reflected in the seasonal pattern of serum levels of Eâ and T in female winter flounder. To investigate the effect of sockeye salmon carbohydrate-poor (Con A I) and carbohydrate- rich (Con A II) pituitary protein fractions on Eâ production,, ovarian follicles with (intact) or without the surface epithelium-thecal cell layer (defolliculated) from rainbow trout (Qncorhvnchus mykiss) were incubated in vitro. It was demonstrated that Con A I in the presence of T is capable of significantly increasing Eâ production in defolliculated ovarian follicles while under similar conditions Con A II (containing the maturational gonadotropin) was not. Purified salmonid and pleuronectid growth hormones (GHs) were tested for their ability to increase either Eâ and T production during in vitro ovarian incubations in both rainbow trout and winter flounder respectively, but were found to be inactive. -- Growth hormones were isolated from the pituitaries of sockeye salmon (Qncorhvnchus nerka) and American plaice (Hippoglossoides platessoides). A bioassay based on the increase of serum triiodothyronine in rainbow trout was developed to follow GH biological activity during pituitary fractionation. The isolation of a pituitary protein from sockeye salmon that was active in the bioassay was confirmed as monomeric GH by an amino-terminal (N-T) amino acid sequence. In plaice GH variants were isolated from two Mr regions within the pituitary, 42,000 and <33,000, that were active in the bioassay and had identical N-T amino acid sequences. The 42,000 Mr form predominates in the plaice pituitary making up 93% of the total
The effects of sublethal pentachlorophenol exposure on reproduction in rainbow trout (Salmo gairdneri)
Decoupled Programs, Payment Incidence, and Factor Markets: Evidence from Market Experiments
We use laboratory market experiments to assess the impact of asymmetric knowledge of a per-unit subsidy and the effect of a decoupled annual income subsidy on factor market outcomes. Results indicate that when the subsidy is tied to the factor as a per-unit subsidy, regardless of full or asymmetric knowledge for market participants, subsidized factor buyers distribute nearly 22 percent of the subsidy to factor sellers. When the subsidy is fully decoupled from the factor, as is the case with the annual payment, payment incidence is mitigated and prices are not statistically different from the no-policy treatment.laboratory market experiments, agricultural subsidies, subsidy incidence, land market, ex ante policy analysis, Agricultural and Food Policy, Institutional and Behavioral Economics, Q18, D03, C92,
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Impact of Tobacco-Related Health Warning Labels across Socioeconomic, Race and Ethnic Groups: Results from a Randomized Web-Based Experiment
Background: The U.S. Family Smoking Prevention and Tobacco Control Act of 2009 requires updating of the existing text-only health warning labels on tobacco packaging with nine new warning statements accompanied by pictorial images. Survey and experimental research in the U.S. and other countries supports the effectiveness of pictorial health warning labels compared with text-only warnings for informing smokers about the risks of smoking and encouraging cessation. Yet very little research has examined differences in reactions to warning labels by race/ethnicity, education or income despite evidence that population subgroups may differ in their ability to process health information. The purpose of the present study was to evaluate the potential impact of pictorial warning labels compared with text-only labels among U.S. adult smokers from diverse racial/ethnic and socioeconomic subgroups. Methods/Findings: Participants were adult smokers recruited from two online research panels (n = 3,371) into a web-based experimental study to view either the new pictorial warnings or text-only warnings. Participants viewed the labels and reported their reactions. Adjusted regression models demonstrated significantly stronger reactions for the pictorial condition for each outcome salience (b = 0.62, p<.001); perceived impact (b = 0.44, p<.001); credibility (OR = 1.41, 95% CI = 1.22â1.62), and intention to quit (OR = 1.30, 95% CI = 1.10â1.53). No significant results were found for interactions between condition and race/ethnicity, education, or income. The only exception concerned the intention to quit outcome, where the condition-by-education interaction was nearly significant (p = 0.057). Conclusions: Findings suggest that the greater impact of the pictorial warning label compared to the text-only warning is consistent across diverse racial/ethnic and socioeconomic populations. Given their great reach, pictorial health warning labels may be one of the few tobacco control policies that have the potential to reduce communication inequalities across groups. Policies that establish strong pictorial warning labels on tobacco packaging may be instrumental in reducing the toll of the tobacco epidemic, particularly within vulnerable communities
Applications of Knowledge Discovery in Massive Transportation Data: The Development of a Transportation Research Informatics Platform (TRIP).
Transportation researchers and practitioners have access to unprecedented amounts of data but lack the tools to easily store, manipulate, and analyze these data. The Transportation Research Informatics Platform (TRIP) is an informatics-based system designed to manage massive amounts of transportation data and provide researchers an efficient way to conduct analytics on big data. The objectives of TRIP include creating the ability to handle massive amounts of transportation data; utilize open-source technologies and tools to ingest, store, align, and process data; accept structured, semistructured, and unstructured datasets from any source; provide an efficient way to query data without indepth knowledge of metadata; integrate with open-source and consumer off-the-shelf analytics products; and provide visualization tools to offer greater insights into data. TRIP architecture is flexible and built on opensource state-of-the-art technology developed with big data in mind. Although predominantly developed for transportation safety research, TRIP is domain agnostic and capable of addressing issues pertaining to operations and maintenance given the ingestion of the appropriate datasets
Applications of Knowledge Discovery in Massive Transportation Data: The Development of a Transportation Research Informatics Platform (TRIP).
Transportation researchers and practitioners have access to unprecedented amounts of data but lack the tools to easily store, manipulate, and analyze these data. The Transportation Research Informatics Platform (TRIP) is an informatics-based system designed to manage massive amounts of transportation data and provide researchers an efficient way to conduct analytics on big data. The objectives of TRIP include creating the ability to handle massive amounts of transportation data; utilize open-source technologies and tools to ingest, store, align, and process data; accept structured, semistructured, and unstructured datasets from any source; provide an efficient way to query data without indepth knowledge of metadata; integrate with open-source and consumer off-the-shelf analytics products; and provide visualization tools to offer greater insights into data. TRIP architecture is flexible and built on opensource state-of-the-art technology developed with big data in mind. Although predominantly developed for transportation safety research, TRIP is domain agnostic and capable of addressing issues pertaining to operations and maintenance given the ingestion of the appropriate datasets
Finite Temperature Dynamical Structure Factor of Alternating Heisenberg Chains
We develop a low-temperature expansion for the finite temperature dynamical
structure factor of the spin half Heisenberg chain with alternating nearest
neighbour exchange in the limit of strong alternation of the exchange
constants. We determine both the broadening of the low lying triplet lines and
the contribution of the thermally activated intraband scattering.Comment: 11 pages, 4 eps-figure
Nanometer-Scale Lateral pân Junctions in Graphene/α-RuCl3 Heterostructures
[EN] The ability to create nanometer-scale lateral p-n junctions is essential for the next generation of two-dimensional (2D) devices. Using the charge-transfer heterostructure graphene/alpha-RuCl3, we realize nanoscale lateral p-n junctions in the vicinity of graphene nanobubbles. Our multipronged experimental approach incorporates scanning tunneling microscopy (STM) and spectroscopy (STS) and scattering-type scanning near-field optical microscopy (s-SNOM) to simultaneously probe the electronic and optical responses of nanobubble p-n junctions. Our STM/STS results reveal that p-n junctions with a band offset of 0.6 eV can be achieved with widths of 3 nm, giving rise to electric fields of order 108 V/m. Concurrent s-SNOM measurements validate a point-scatterer formalism for modeling the interaction of surface plasmon polaritons (SPPs) with nanobubbles. Ab initio density functional theory (DFT) calculations corroborate our experimental data and reveal the dependence of charge transfer on layer separation. Our study provides experimental and conceptual foundations for generating p-n nanojunctions in 2D materials.Research at Columbia University was supported as part of the Energy Frontier Research Center on Programmable Quantum Materials funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Award No DE-SC0019443. Plasmonic nano-imaging at Columbia University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Award No DE-SC0018426. J.Z. and A.R. were supported by the European Research Council (ERC-2015-AdG694097), the Cluster of Excellence âAdvanced Imaging of Matterâ (AIM) EXC 2056-390715994, funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under RTG 2247, Grupos Consolidados (IT1249-19), and SFB925 âLight induced dynamics and control of correlated quantum systemsâ. J.Z. and A.R. would like to acknowledge Nicolas Tancogne-Dejean and Lede Xian for fruitful discussions and also acknowledge support by the Max Planck Institute-New York City Center for Non-Equilibrium Quantum Phenomena. The Flatiron Institute is a division of the Simons Foundation. J.Z. acknowledges funding received from the European Union Horizon 2020 research and innovation programme under Marie SkĆodowska-Curie Grant Agreement 886291 (PeSD-NeSL). STM support was provided by the National Science Foundation via Grant DMR-2004691. C.R.-V. acknowledges funding from the European Union Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie Grant Agreement 844271. D.G.M. acknowledges support from the Gordon and Betty Moore Foundationâs EPiQS Initiative, Grant GBMF9069. J.Q.Y. was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. S.E.N. acknowledges support from the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Division of Scientific User Facilities. Work at University of Tennessee was supported by NSF Grant 180896
Graphene/-RuCl: An Emergent 2D Plasmonic Interface
Work function-mediated charge transfer in graphene/-RuCl
heterostructures has been proposed as a strategy for generating highly-doped 2D
interfaces. In this geometry, graphene should become sufficiently doped to host
surface and edge plasmon-polaritons (SPPs and EPPs, respectively).
Characterization of the SPP and EPP behavior as a function of frequency and
temperature can be used to simultaneously probe the magnitude of interlayer
charge transfer while extracting the optical response of the interfacial doped
-RuCl. We accomplish this using scanning near-field optical
microscopy (SNOM) in conjunction with first-principles DFT calculations. This
reveals massive interlayer charge transfer (2.7 10 cm)
and enhanced optical conductivity in -RuCl as a result of
significant electron doping. Our results provide a general strategy for
generating highly-doped plasmonic interfaces in the 2D limit in a scanning
probe-accessible geometry without need of an electrostatic gate.Comment: 22 pages, 5 figure
An instructive role for Interleukin-7 receptor α in the development of human B-cell precursor leukemia
© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the articleâs Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the articleâs Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Kinase signaling fuels growth of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Yet its role in leukemia initiation is unclear and has not been shown in primary human hematopoietic cells. We previously described activating mutations in interleukin-7 receptor alpha (IL7RA) in poor-prognosis "ph-like" BCP-ALL. Here we show that expression of activated mutant IL7RA in human CD34+ hematopoietic stem and progenitor cells induces a preleukemic state in transplanted immunodeficient NOD/LtSz-scid IL2RÎłnull mice, characterized by persistence of self-renewing Pro-B cells with non-productive V(D)J gene rearrangements. Preleukemic CD34+CD10highCD19+ cells evolve into BCP-ALL with spontaneously acquired Cyclin Dependent Kinase Inhibitor 2 A (CDKN2A) deletions, as commonly observed in primary human BCP-ALL. CRISPR mediated gene silencing of CDKN2A in primary human CD34+ cells transduced with activated IL7RA results in robust development of BCP-ALLs in-vivo. Thus, we demonstrate that constitutive activation of IL7RA can initiate preleukemia in primary human hematopoietic progenitors and cooperates with CDKN2A silencing in progression into BCP-ALL.This work was supported by the Israel Science Foundation (# 1178/12 to S.I.), Children with Cancer (UK) (S.I. and T.E.), Swiss Bridge Foundation (S.I.), WLBH Foundation (S.I.), Waxman Cancer Research Foundation (S.I.), USâIsrael Binational Science Foundation, Israeli health ministry ERA-NET program (#CANCER11-FP-127 to S.I.), Hans Neufeld Stiftung, the International Collaboration Grant from the Jacki and Bruce Barron Cancer Research Scholarsâ Program, a partnership of the Israel Cancer Research Fund and City of Hope (S.I. grants # 00161), the Nevzlin Genomic Center for Precision Medicine in Schneider Childrenâs Medical Center of Israel, The European Unionâs Horizon 2020 research and innovation programme under the Marie SkĆodowska-Curie grant agreement No 813091 (S.I.) and the Israel Childhood Cancer Foundation (S.I.). I.G. was partially supported by Israeli ministry of Immigrant Absorption.info:eu-repo/semantics/publishedVersio
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