[1] This study is concerned with the quantitative prediction of dust storms in real time. An integrated wind erosion modeling system is used for 24-, 48-, and 72-hour forecasts of northeast Asian dust events for March and April 2002. The predictions are validated with synoptic records from the meteorological network and dust concentration measurements at 12 stations in China, Japan, and Korea. The predicted spatial patterns and temporal evolutions of dust events and the predicted near-surface dust concentrations are found to agree well with the observations. The validation confirms the capacity of the modeling system in quantitative forecasting of dust events in real time. On the basis of the predictions, dust activities in northeast Asia are examined using quantities such as dust emission, deposition, and load. During an individual dust episode, dust sources and intensities vary in space and time, but on average the Gobi Desert, the Hexi (Yellow River West) Corridor, the Chaidam Basin, the Tulufan Basin, and the fringes of the Talimu and Zhunge'er Basins are identified to be the main source regions. The Gobi Desert is the strongest dust source, where the maximum dust emission reaches 5000 mg m À2 s À1 and the net dust emission reaches 16 t km À2 d À1 in March and April 2002. Net dust deposition covers a large area, with the Loess Plateau receiving about 1.6 to 4.3 t km À2 d À1. A zone of high dust load exists along the northern boundary of the Tibet Plateau, with a maximum of around 2 t km À2 situated over the Gobi Desert. The total dust emission, total dust deposition, and total dust load for the domain of the simulation are estimated. The average (maximum) total dust emission is 11.5 Â 10 6 (65.7 Â 10 6 ) t d À1 , the average (maximum) total dust deposition is 10.8 Â 10 6 (51.4 Â 10 6 ) t d À1 , and the average (maximum) total dust load is 5.5 Â 10 6 (15.9 Â 10 6 ) t.

In this paper, the synoptic features of Northeast Asian dust events in spring are studied. Using surface meteorological records for March, April and May of 2000, 2001 and 2002, the distribution of dust-event frequencies, possible dust-source regions and the synoptic conditions responsible for dust activities are examined. Four regions of frequent dust events are found in the domain of analysis. These are the Tarim Basin, the southern Mongolia and the Inner Mongolia Autonomous Region of China, the Hexi (Yellow River West) Corridor and the northern part of the Indian Subcontinent. The Tarim Basin has the highest dust-event frequency, with most of the events being weak ones (classi ed as dust-in-suspension). Dust events occur less frequently in the Gobi Desert, but they are often severe and widespread. Dust concentrations in the Tarim and the Gobi regions are found to be of similar order of magnitude with (averaged) maximum values reaching 1 mg m 3. In different regions, dust events are generated by different synoptic systems. Over the Gobi, almost all dust events arise from the strong northwesterly winds associated with low-pressure systems. In the Tarim Basin, dust events are mostly associated with light winds. Strong northeasterly winds may affect the eastern and southeastern parts of the basin, generating dust storms. It is shown that topography plays a signi cant role in the transport of dust particles. A preferred route of dust transport is found to exist along the northeastern boundary, and another along the southern boundary, of the Tibetan Plateau. It is suggested that the mechanisms for dust emission in the Tarim Basin requires further investigation. Zusammenfassung In diesem Artikel werden die synoptischen Merkmale von nordostasiatischen Staubereignissen untersucht. Aus meteorologischen Bodenbeobachtungen der Monate März, April und Mai der Jahre 2000 bis 2002 werden die Häu gkeitsverteilung solcher Staubereignisse, mögliche Herkunftsregionen des Staubes, sowie die synoptischen Bedingungen für deren Auftreten untersucht. Man ndet vier Regionen mit häu gen Staubereignissen im Untersuchungsgebiet: das Tarim Becken, die südliche Mongolei und die Autonome Region Innere Mongolei in China, der Hexi Korridor (Westlicher Gelber Fluss) und der nördliche Teil des Indischen Subkontinents. Das Tarim Becken zeigt die höchste Zahl von Staubereignissen, wobei die meisten davon leicht sind (klassiert als Staubtrübung). In der Wüste Gobi treten Staubereignisse weniger häu g auf, sind dann aber kräftiger und groß ächiger. Die Staubkonzentrationen im Tarim Becken und in der Wüste Gobi sind von derselben Größenordnung mit (gemittelten) Maximalwerten von 1 mg m 3. In den verschiedenen Gegenden werden die Staubereignisse durch unterschiedliche synoptische Systeme erzeugt.Über der Wüste Gobi entstehen fast alle Staubereignisse durch kräftige nordwestliche Winde in Verbindung mit Tiefdrucksystemen. Im Tarim Becken treten die Ereignisse in Verbindung mit schwachen Winden auf. Starke Nordostwinde können in denöstlichen und südöstli...

The importance of gonadal hormones in the regulation of vascular function has been documented. An alternate and essential contribution of the sex chromosomes to sex differences in vascular function is poorly understood. We reported previously sex differences in microvessel permeability (P(s)) responses to adenosine that were mediated by the cAMP signaling pathway (Wang J, PhD thesis, 2005; Wang J and Huxley V, Proceedings of the VIII World Congress of Microcirculation, 2007; Wang J and Huxley VH, Am J Physiol Heart Circ Physiol 291: H3094-H3105, 2006). The two cyclic nucleotides, cAMP and cGMP, central to the regulation of vascular barrier integrity, are hydrolyzed by phosphodiesterases (PDE). We hypothesized that microvascular endothelial cells (EC) would retain intrinsic and inheritable sexually dimorphic genes with respect to the PDEs modulating EC barrier function. Primary cultured microvascular EC from skeletal muscles isolated from male and female rats, respectively, were used. SRY (a sex-determining region Y gene) mRNA expression was observed exclusively in male, not female, cells. The predominant isoform among PDE1-5, present in both XY and XX EC, was PDE4. Expression mRNA levels of PDE1A (male > female) and PDE3B (male < female) were sex dependent; PDE2A, PDE4D, and PDE5A were sex independent. Barrier function, P(s), was determined from measures of albumin flux across confluent primary cultured microvessel XY and XX EC monolayers. Consistent with intact in situ microvessels, basal monolayer P(s) did not differ between XY (1.7 +/- 0.2 x 10(-6) cm/s; n = 8) and XX (1.8 +/- 0.1 x 10(-6) cm/s; n = 10) EC. Cilostazol, a PDE3 inhibitor, reduced (11%, P < 0.05) P(s) in XX, not XY, cells. These findings demonstrate the presence and maintenance of intrinsic sex-related differences in gene expression and cellular phenotype by microvascular EC in a gonadal-hormone-free environment. Furthermore, intrinsic cell-sex likely contributes significantly to sexual dimorphism in cardiovascular function.

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In microvessels, acute inflammation is typified by an increase in leukocyte-endothelial cell interactions, culminating in leukocyte transmigration into the tissue, and increased permeability to water and solutes, resulting in tissue edema. The goal of this study was to establish a method to quantify solute permeability (P(s)) changes in microvessels in intact predominantly blood-perfused networks in which leukocyte transmigratory behavior could be precisely described using established paradigms. We used intravital confocal microscopy to measure solute (BSA) flux across microvessel walls, hence P(s). A quantitative fluorescence approach (Huxley VH, Curry FE, and Adamson RH. Am J Physiol Heart Circ Physiol 252: H188-H197, 1987) was adapted to the imaged confocal tissue slice in which the fluorescent source volume and source surface area of the microvessel were restricted to the region of vessel that was contained within the imaged confocal tissue section. P(s) measurements were made in intact cremaster muscle microvasculature of anesthetized mice and compared with measurements of P(s) made in isolated rat skeletal muscle microvessels. Mouse arteriolar P(s) was 9.9 +/- 1.1 x 10(-7) cm/s (n = 16), which was not different from 8.4 +/- 1.3 x 10(-7) cm/s (n = 6) in rat arterioles. Values in venules were significantly (P < 0.05) higher: 44.4 +/- 7.9 x 10(-7) cm/s (n = 14) in mice and 25.0 +/- 3.7 x 10(-7) cm/s in rats. Convective coupling was estimated to contribute <10% to the measured P(s) in both microvessel types and both animal models. We conclude that this approach provides an appropriate quantification of P(s) in the intact microvasculature and that arteriolar P(s), while lower than in venules, is nevertheless consistent with arterioles being a significant source of interstitial protein.

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Gender influences volume regulation via several mechanisms; whether these include microvascular exchange, especially in the heart, is not known. In response to adenosine (Ado), permeability (P s )to protein of coronary arterioles of female pigs decreases acutely. Whether Ado induces similar P s changes in arterioles from males or whether equivalent responses occur in coronary venules of either sex has not been determined. Hypotheses that 1) basal P s properties and 2) P s responses to vasoactive stimuli are sex independent were evaluated from measures of P s to two hydrophilic proteins, α-lactalbumin and porcine serum albumin (PSA), in arterioles and venules isolated from hearts of adult male and female pigs. Consistent with hypothesis 1, basal P s values of both microvessel types were independent of sex. Contrary to hypothesis 2, P s responses to Ado varied with sex, protein, and vessel type. Confirming earlier studies, Ado induced a ~20% decrease in P s to both proteins in coronary arterioles from females. In arterioles from males, Ado did not change P s for α-lactalbumin ( , 3 ± 13%) whereas P s for PSA ( ) decreased by 27 ± 8% (P < 0.005). In venules from females, Ado elevated by 44 ± 20% (P < 0.05), whereas in those from males, Ado reduced by 24 ± 5% (P < 0.05). The variety of outcomes is consistent with transvascular protein and protein-carried solute flux being regulated by multiple sex-dependent mechanisms in the heart and provides evidence of differences in exchange homeostasis of males and females in health and, likely, disease.

MicroRNA plays an important role in gastric cancer (GC) development, while the function of miR-497-5p in this disease remains unknown. In the present study, we demonstrated miR-497-5p as a tumor suppressive microRNA in GC. miR-497-5p was down-regulated in GC tissues and its expression was associated with the disease stage. Inhibition of miR-497-5p promoted GC cell proliferation and growth. By contrast, miR-497-5p ectopic expression suppressed the proliferation and growth of GC cells. In addition, miR-497-5p inhibited DNA synthesis and enhanced apoptosis in GC cells. The cell cycle progression was suppressed by miR-497-5p. Mechanistically, miR-497-5p directly targeted and suppressed the expression of pyruvate dehydrogenase kinase 3 (PDK3), which is highly expressed in GC tissues. Over-expression of PDK3 promoted the proliferation of GC cells. Our study revealed that miR-497-5p inhibited GC cell proliferation and growth via targeting PDK3.