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1.
Sci Data ; 10(1): 408, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355660

RESUMO

This is a global ocean climatological dataset of 17 thermohaline parameters such as isothermal layer (ITL) depth (hT), mixed layer (ML) depth (hD), thermocline gradient (GT), pycnocline gradient (GD) determined from temperature (T) and salinity (S) profiles of the National Centers for Environmental Information (NCEI) world ocean atlas 2018 (WOA18) using the double gradient method along with the identity-index (i-index) showing the quality of the determination. With the identified (hT, hD) and (GT, GD), other parameters such as ITL heat content (HITL), mixed layer fresh-water content (FML), maximum thermocline gradient (GTmax), thermocline depth (hth), temperature at thermocline depth (Tth), maximum density gradient GDmax), pycnocline depth (hpyc), density at pycnocline depth (ρpyc), and (hT - hD) (barrier layer if positive or compensated layer if negative). The dataset is located at the NOAA/NCEI website ( https://doi.org/10.25921/j3v2-jy50 ). It provides useful background information for ocean mixed layer dynamics, air-sea interaction, climatological studies. This paper is the only document for the dataset.

2.
Sci Rep ; 11(1): 3235, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547333

RESUMO

Two different treatments in ocean dynamics are found between the gravity and pressure gradient force. Vertical component is 5-6 orders of magnitude larger than horizontal components for the pressure gradient force in large-scale motion, and for the gravity in any scale motion. The horizontal pressure gradient force is considered as a dominant force in oceanic motion from planetary to small scales. However, the horizontal gravity is omitted in oceanography completely. A non-dimensional C number (ratio between the horizontal gravity and the Coriolis force) is used to identify the importance of horizontal gravity in the ocean dynamics. Unexpectedly large C number with the global mean around 24 is obtained using the community datasets of the marine geoid height and ocean surface currents. New large-scale ocean dynamic equations with the real gravity are presented such as hydrostatic balance, geostrophic equilibrium, thermal wind, equipotential coordinate system, and vorticity equation.

3.
Sci Rep ; 10(1): 1445, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996755

RESUMO

Absolute geostrophic current at the ocean surface (S) contains three components: (1) absolute geostrophic current at the geoid undulation (N), (2) geostrophic shear (between S and N) due to horizontal gradient of dynamic ocean topography, and (3) geostrophic shear (between S and N) due to horizontal gradient of density. However, only the second component is used to represent the surface absolute geostrophic current in physical oceanography and satellite geodesy. Four public datasets are used to calculate each component. Evident difference between the surface absolute geostrophic current and the second component (i.e., geostrophic shear due to horizontal gradient of dynamic ocean topography) was found by the statistical characteristics with the relative root mean square difference of 0.605. It shows that the common practice in physical oceanography and satellite geodesy is not correct. The horizontal gradient of dynamic ocean topography alone cannot be claimed as the surface absolute geostrophic current.

4.
Sci Data ; 6(1): 119, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292448

RESUMO

Different from the existing global ocean climatological datasets of isothermal layer (ITL) depth (h), a global ocean synoptic dataset of h along with other parameters has been established from temperature profiles of the National Centers for Environmental Information (NCEI) world ocean database 1961-2017. The exponential leap-forward gradient method was used to identify h and thermocline gradient (G) from each temperature profile measured by expendable bathythermograph (XBT) and conductivity, temperature, depth (CTD) instruments. Due to quality and vertical resolution of the profiling data, the numbers of (G, h) pairs are 446,811 out of 964,942 CTD profiles and 755,086 out of 2,303,433 XBT profiles. With the given h, other parameters such as ITL heat content (HITL), sea surface temperature (SST), temperature below ITL (Tm), and quality measures (Q, I) indices are provided. Altogether, the dataset contains 1,201,897 temporally and horizontally varying sets of (G, h, HITL, SST, Tm, Q-index, I-index). Note that we added 200° to the longitude. This synoptic dataset is located on the NCEI website for public use.

5.
Environ Int ; 34(5): 688-97, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18258303

RESUMO

Lanzhou is one of the major industrial cities in northwest China, the capital of Gansu Province, and located at a northwest-to-southeast oriented valley basin with elevation about 1500-1600-m. Due to topographic and meteorological characteristics, Lanzhou is one of the most polluted cities in China. Meteorological conditions (low winds, stable stratification especially inversion), pollutant sources and sinks affect the air quality. Lanzhou government carried out afforestation and pollutant-source reduction (closing several heavy industrial factories) to improve the air quality for the past two decades. In this study, effect of afforestation on reducing the NO(X) concentration is investigated numerically using RAMS-HYPACT model.


Assuntos
Poluentes Atmosféricos/análise , Óxidos de Nitrogênio/análise , China , Modelos Teóricos
6.
Environ Int ; 34(5): 698-713, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18234337

RESUMO

Concentrations of total suspended particles (TSP) and PM(10) in Lanzhou China have been kept high for the past two decades. Data collected during the intensive observational period from October 1999 to April 2001 show high TSP and PM(10) concentrations. Starting from November, the PM(10) pollution intensifies, and reaches mid to high alert level of air pollution, continues until April next year, and is at low alert level in the summer. In the winter and spring, the TSP concentration is 2-10 times higher than the third-level criterion of air quality (severe pollution). Effects of intrinsic factors (sources of pollution) and remote preconditions (propagation of dust storms) for severe PM(10) and TSP pollution in Lanzhou are analyzed.


Assuntos
Poluentes Atmosféricos/análise , Tamanho da Partícula , China , Estações do Ano
7.
Sci Rep ; 12(1): 6773, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474333
8.
Sci Rep ; 11(1): 7038, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33758285
9.
J Immunol ; 174(9): 5288-97, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15843525

RESUMO

TRAC-1 (T cell RING (really interesting new gene) protein identified in activation screen) is a novel E3 ubiquitin ligase identified from a retroviral vector-based T cell surface activation marker screen. The C-terminal truncated TRAC-1 specifically inhibited anti-TCR-mediated CD69 up-regulation in Jurkat cells, a human T leukemic cell line. In this study, we show that TRAC-1 is a RING finger ubiquitin E3 ligase with highest expression in lymphoid tissues. Point mutations that disrupt the Zn(2+)-chelating ability of its amino-terminal RING finger domain abolished TRAC-1's ligase activity and the dominant inhibitory effect of C-terminal truncated TRAC-1 on TCR stimulation. The results of in vitro biochemical studies indicate that TRAC-1 can stimulate the formation of both K48- and K63-linked polyubiquitin chains and therefore could potentially activate both degradative and regulatory ubiquitin-dependent pathways. Antisense oligonucleotides to TRAC-1 specifically reduced TRAC-1 mRNA levels in Jurkat and primary T cells and inhibited their activation in response to TCR cross-linking. Collectively, these results indicate that the E3 ubiquitin ligase TRAC-1 functions as a positive regulator of T cell activation.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Ativação Linfocitária/imunologia , Proteínas Nucleares/fisiologia , Linfócitos T/enzimologia , Linfócitos T/imunologia , Ubiquitina-Proteína Ligases/fisiologia , Regulação para Cima/imunologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Sequência de Bases , Catálise , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/isolamento & purificação , Linhagem Celular , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Humanos , Células Jurkat , Ativação Linfocitária/genética , Tecido Linfoide/citologia , Tecido Linfoide/enzimologia , Tecido Linfoide/imunologia , Dados de Sequência Molecular , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Proteínas Nucleares/isolamento & purificação , Correpressor 2 de Receptor Nuclear , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Poliubiquitina/metabolismo , Receptores de Antígenos de Linfócitos T/fisiologia , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/isolamento & purificação , Regulação para Cima/genética
10.
J Immunol ; 172(12): 7324-34, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15187108

RESUMO

To identify novel components of the TCR signaling pathway, a large-scale retroviral-based functional screen was performed using CD69 expression as a marker for T cell activation. In addition to known regulators, two truncated forms of p21-activated kinase 2 (PAK2), PAK2DeltaL(1-224) and PAK2DeltaS(1-113), both lacking the kinase domain, were isolated in the T cell screen. The PAK2 truncation, PAK2DeltaL, blocked Ag receptor-induced NFAT activation and TCR-mediated calcium flux in Jurkat T cells. However, it had minimal effect on PMA/ionomycin-induced CD69 up-regulation in Jurkat cells, on anti-IgM-mediated CD69 up-regulation in B cells, or on the migratory responses of resting T cells to chemoattractants. We show that PAK2 kinase activity is increased in response to TCR stimulation. Furthermore, a full-length kinase-inactive form of PAK2 blocked both TCR-induced CD69 up-regulation and NFAT activity in Jurkat cells, demonstrating that kinase activity is required for PAK2 function downstream of the TCR. We also generated a GFP-fused PAK2 truncation lacking the Cdc42/Rac interactive binding region domain, GFP-PAK2(83-149). We show that this construct binds directly to the kinase domain of PAK2 and inhibits anti-TCR-stimulated T cell activation. Finally, we demonstrate that, in primary T cells, dominant-negative PAK2 prevented anti-CD3/CD28-induced IL-2 production, and TCR-induced CD40 ligand expression, both key functions of activated T cells. Taken together, these results suggest a novel role for PAK2 as a positive regulator of T cell activation.


Assuntos
Ativação Linfocitária , Proteínas Nucleares , Proteínas Serina-Treonina Quinases/imunologia , Linfócitos T/imunologia , Antígenos CD/análise , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/análise , Antígenos de Diferenciação de Linfócitos T/biossíntese , Linfócitos B/metabolismo , Biomarcadores/análise , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Humanos , Lectinas Tipo C , Mutação , Fatores de Transcrição NFATC , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/fisiologia , Estrutura Terciária de Proteína , Receptores de Antígenos de Linfócitos T/fisiologia , Transdução de Sinais , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo , Quinases Ativadas por p21
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