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Biomass burning emisison inventory with daily resolution: Application to aircraft observations of Asian outflow
We develop a daily-resolved global emission inventory for biomass burning using AVHRR satellite observations of fire activity corrected for data gaps and scan angle biases. We implemented this inventory in a global three-dimensional model (GEOSCHEM) to simulate aircraft CO observations during the TRACE-P mission over the NW Pacific in February-April 2001. Seasonal biomass burning in SE Asia was a major contributor to the outflow of Asian pollution observed in TRACE-P and shows large day-to-day fluctuations that vary depending on location. Three simulations were conducted with the same 3-month total (February-April) emissions but different temporal distributions: 2001 daily resolved, 2001 monthly resolved, and climatological monthly resolved. The effect of daily resolved versus monthly resolved 2001 emissions in the simulation of CO is less than 8 ppbv in Asian outflow over the NW Pacific but can exceed 100 ppbv over source regions. The relatively small effect in Asian outflow reflects spatial and temporal averaging of emissions during ageing in the continental boundary layer. Significant improvement in the simulation of TRACE-P observations (as diagnosed by the resolved variance) is found when using 2001 monthly versus climatological monthly emissions, but using 2001 daily emissions does not offer further improvement. Copyright 2003 by the American Geophysical Union
Electric-field-induced phase transition of <001> oriented Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals
oriented 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 single crystals were poled under
different electric fields, i.e. Epoling=4 kV/cm and Epoling=13 kV/cm. In
addition to the temperature-dependent dielectric constant measurement, X-ray
diffraction was also used to identify the poling-induced phase transitions.
Results showed that the phase transition significantly depends on the poling
intensity. A weaker field (Epoling=4 kV/cm) can overcome the effect of random
internal field to perform the phase transition from rhombohedral ferroelectric
state with short range ordering (microdomain) FESRO to rhombohedral
ferroelectric state with long range ordering (macrodomain) FElRO. But the
rhombohedral ferroelectric to tetragonal ferroelectric phase transition
originating from to polarization rotation can only be induced by a
stronger field (Epoling=13 kV/cm). The sample poled at Epoling=4 kV/cm showed
higher piezoelectric constant, d33>1500 pC/N, than the sample poled at
Epoling=13 kV/cm.Comment: 7 pages, 2 figure
TNFα enhances the motility and invasiveness of prostatic cancer cells by stimulating the expression of selective glycosyl- and sulfotransferase genes involved in the synthesis of selectin ligands.
Sialyl Lewis x (sLe(x)) plays an important role in cancer metastasis. But, the mechanism for its production in metastatic cancers remains unclear. The objective of current study was to examine the effects of a proinflammatory cytokine on the expression of glycosyltransferase and sulfotransferase genes involved in the synthesis of selectin ligands in a prostate cancer cell line. Androgen-independent human lymph node-derived metastatic prostate cancer cells (C-81 LNCaP), which express functional androgen receptor and mimic the castration-resistant advanced prostate cancer, were used. TNFα treatment of these cells increased their binding to P-, E- and L-selectins, anti-sLe(x) antibody, and anti-6-sulfo-sialyl Lewis x antibody by 12%, 240%, 43%, 248% and 21%, respectively. Also, the expression of C2GnT-1, B4GalT1, GlcNAc6ST3, and ST3Gal3 genes was significantly upregulated. Further treatment of TNFα-treated cells with either anti-sLe(x) antibody or E-selectin significantly suppressed their in vitro migration (81% and 52%, respectively) and invasion (45% and 56%, respectively). Our data indicate that TNFα treatment enhances the motility and invasion properties of LNCaP C-81 cells by increasing the formation of selectin ligands through stimulation of the expression of selective glycosyl- and sulfotransferase genes. These results support the hypothesis that inflammation contributes to cancer metastasis
Effect of Zinc Supplementation on Growth of Low Birth Weight Infants Aged 1â6 Mo in Ardabil, Iran
Objective To assess the effect of zinc supplementation on growth of low birth weight (LBW) infants aged 1â6 mo. Methods LBW infants were enrolled at birth and randomly assigned to receive 5 mg elemental Zn per day (n=45) or placebo (n=45) until 6 mo of age. They were followed monthly for information on compliance; anthropometric measurements were performed monthly. Results After randomization, 5 infants from zinc group and 9 from placebo group were excluded. At 6 mo of age, significantly greater weight gains were observed in the zinc than in the placebo group (4995±741g in zinc group vs. 3896±865 g in placebo group, p = 0.036). Length gain during the study period improved in zinc group (16.9±8.2 cm vs. 15.1±4.1 cm, p = 0.039); after zinc supplementation head circumference were increased (8.7±1.4 cm vs.7.4±
1.5 cm p<0.001). In male infants, total weight gain and height and head circumference gain were higher in the zinc than in the placebo group. However, only head circumference change was statistically significant. A similar trend was observed among female infants, but these differences were not statistically significant. There was no significant relation between breast-feeding status and the main outcome variables. Conclusions Infants in the present study showed improveÂŹments in growth rate, but more studies are required in this field to confirm this fact
Chemical Bonding of Transition-metal Co Clusters with Graphene
We carried out density functional calculation to study Co clusters on
graphene. We deposit several free isomers in different disposition respect to
hexagonal lattice nodes, studying even the isomer recently obtained
as the most stable one. Surprisingly, Co clusters bonded to graphene
prefer structures where the low lying isomer is much
distorted, because it is linked with more bonds than in previous works. For any
isomer the most stable position binds to graphene by the Co atoms that can lose
electrons. We find that the charge transfers between graphene and clusters are
small enough to conclude that the Co-graphene binding is not ionic-like but
chemical. Besides, the same order of stability among the different isomers on
doped graphene is well kept. These findings could also be of interest for
magnetic clusters on graphenic nanostructures such as ribbons and nanotubes.Comment: 12 pages, 6 figure
Perceived Barriers to Application of Glycaemic Index: Valid Concerns or Lost in Translation?
The term glycaemic-index (GI) originally appeared in the literature in the early 1980s. GI categorizes carbohydrate according to glycaemic effect postprandially. Since its inception, GI has obtained and maintained interest of academics and clinicians globally. Upon review of GI literature, it becomes clear that the clinical utility of GI is a source of controversy. Can and should GI be applied clinically? There are academics and clinicians on both sides of the argument. Certainly, this controversy has been a stimulus for the evolution of GI methodology and application research, but may also negatively impact cliniciansâ perception of GI if misunderstood. This article reviews two assessments of GI that are often listed as barriers to application; the GI concept is (1) too complex and (2) too difficult for clients to apply. The literature reviewed does not support the majority of purported barriers, but does indicate that there is a call from clinicians for more and improved GI education tools and clinician GI education. The literature indicates that the Registered Dietitian (RD) can play a key role in GI knowledge translation; from research to application. Research is warranted to assess GI education tool and knowledge needs of clinicians and the clients they serve
Charged particle production in the Pb+Pb system at 158 GeV/c per nucleon
Charged particle multiplicities from high multiplicity central interactions
of 158 GeV/nucleon Pb ions with Pb target nuclei have been measured in the
central and far forward projectile spectator regions using emulsion chambers.
Multiplicities are significantly lower than predicted by Monte Carlo
simulations. We examine the shape of the pseudorapidity distribution and its
dependence on centrality in detail.Comment: 17 pages text plus 12 figures in postscript 12/23/99 -- Add TeX
version of sourc
Oral Pathobiont Activates Anti-Apoptotic Pathway, Promoting both Immune Suppression and Oncogenic Cell Proliferation.
Chronic periodontitis (CP) is a microbial dysbiotic disease linked to increased risk of oral squamous cell carcinomas (OSCCs). To address the underlying mechanisms, mouse and human cell infection models and human biopsy samples were employed. We show that the \u27keystone\u27 pathogen Porphyromonas gingivalis, disrupts immune surveillance by generating myeloid-derived dendritic suppressor cells (MDDSCs) from monocytes. MDDSCs inhibit CTLs and induce FOXP3â+â
Distorted magnetic orders and electronic structures of tetragonal FeSe from first-principles
We use the state-of-the-arts density-functional-theory method to study
various magnetic orders and their effects on the electronic structures of the
FeSe. Our calculated results show that, for the spins of the single Fe layer,
the striped antiferromagnetic orders with distortion are more favorable in
total energy than the checkerboard antiferromagnetic orders with tetragonal
symmetry, which is consistent with known experimental data, and the inter-layer
magnetic interaction is very weak. We investigate the electronic structures and
magnetic property of the distorted phases. We also present our calculated spin
coupling constants and discuss the reduction of the Fe magnetic moment by
quantum many-body effects. These results are useful to understand the
structural, magnetic, and electronic properties of FeSe, and may have some
helpful implications to other FeAs-based materials
New Insights into the Organization, Recombination, Expression and Functional Mechanism of Low Molecular Weight Glutenin Subunit Genes in Bread Wheat
The bread-making quality of wheat is strongly influenced by multiple low molecular weight glutenin subunit (LMW-GS) proteins expressed in the seeds. However, the organization, recombination and expression of LMW-GS genes and their functional mechanism in bread-making are not well understood. Here we report a systematic molecular analysis of LMW-GS genes located at the orthologous Glu-3 loci (Glu-A3, B3 and D3) of bread wheat using complementary approaches (genome wide characterization of gene members, expression profiling, proteomic analysis). Fourteen unique LMW-GS genes were identified for Xiaoyan 54 (with superior bread-making quality). Molecular mapping and recombination analyses revealed that the three Glu-3 loci of Xiaoyan 54 harbored dissimilar numbers of LMW-GS genes and covered different genetic distances. The number of expressed LMW-GS in the seeds was higher in Xiaoyan 54 than in Jing 411 (with relatively poor bread-making quality). This correlated with the finding of higher numbers of active LMW-GS genes at the A3 and D3 loci in Xiaoyan 54. Association analysis using recombinant inbred lines suggested that positive interactions, conferred by genetic combinations of the Glu-3 locus alleles with more numerous active LMW-GS genes, were generally important for the recombinant progenies to attain high Zeleny sedimentation value (ZSV), an important indicator of bread-making quality. A higher number of active LMW-GS genes tended to lead to a more elevated ZSV, although this tendency was influenced by genetic background. This work provides substantial new insights into the genomic organization and expression of LMW-GS genes, and molecular genetic evidence suggesting that these genes contribute quantitatively to bread-making quality in hexaploid wheat. Our analysis also indicates that selection for high numbers of active LMW-GS genes can be used for improvement of bread-making quality in wheat breeding
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