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The Arctic climate is modulated, in part, by atmospheric aerosols that affect the distribution of radiant energy passing through the atmosphere. Aerosols affect the surface‐atmosphere radiation balance directly through interactions with solar and terrestrial radiation and indirectly through interactions with cloud particles. Better quantification of the radiative forcing by different types of aerosol is needed to improve predictions of future climate. During April 2009, the airborne campaign Pan‐Arctic Measurements and Arctic Regional Climate Model Inter‐comparison Project (PAM‐ARCMIP) was conducted. The mission was organized by Alfred Wegener Institute for Polar and Marine Research of Germany and utilized their research aircraft, Polar‐5. The goal was to obtain a snapshot of surface and atmospheric conditions over the central Arctic prior to the onset of the melt season. Characterizing aerosols was one objective of the campaign. Standard Sun photometric procedures were adopted to quantify aerosol optical depth AOD, providing a three‐dimensional view of the aerosol, which was primarily haze from anthropogenic sources. Independent, in situ measurements of particle size distribution and light extinction, derived from airborne lidar, are used to corroborate inferences made using the AOD results. During April 2009, from the European to the Alaskan Arctic, from sub‐Arctic latitudes to near the pole, the atmosphere was variably hazy with total column AOD at 500 nm ranging from ∼0.12 to >0.35, values that are anomalously high compared with previous years. The haze, transported primarily from Eurasian industrial regions, was concentrated within and just above the surface‐based temperature inversion layer. Extinction, as measured using an onboard lidar system, was also greatest at low levels, where particles tended to be slightly larger than at upper levels. Black carbon (BC) (soot) was observed at all levels sampled, but at moderate to low concentrations compared with historical records. BC was highest near the North Pole, suggesting there had been an accumulation of soot within the Arctic vortex. Few, optically thick elevated aerosol layers were observed along the flight track, although independent lidar observations reveal evidence of the passage of volcanic plumes, which may have contributed to abnormally high values of AOD above 4 km. Enhanced opacity at higher altitudes during the campaign is attributed to an accumulation of industrial pollutants in the upper troposphere in combination with volcanic aerosol resulting from the March–April 2009 eruptions of Mount Redoubt in Alaska. The presence of Arctic haze during April 2009 is estimated to have reduced the net shortwave irradiance by ∼2–5 W m−2, resulting in a slight cooling of the surface.

A novel sort of cellular titanium foam with the porosity of 86–90% and the main-pore size of 0.5–3.0 mm was successfully prepared. Such foam exhibited a compressive curve showing three regimes: the initial elasticity, the middle zigzag plateau, and the final “densification.” This “densification” presented a course that the broken pieces continually accumulated in those pores which were unbroken or not entirely broken. The fracture morphology suggested that the compressive failure was typically brittle for this titanium foam. The electromagnetic shielding performance was investigated in the radio wave frequency range (0.3–3000 MHz) for this foam, which showed an evident effectiveness with a good performance at low frequencies. On the whole, the effectiveness would be superior while the porosity of the sample was relatively small. It could be inferred that the present foam samples would perform their electromagnetic shielding mainly by the reflection loss mechanism in the low-frequency range, and give priority to the absorption loss mechanism at the upper-frequencies.

Ice fog and frost occur commonly (at least 26% of the time) in the northern latitudes and Arctic regions during winter at temperatures usually less than about −15°C. Ice fog is strongly related to frost formation—a major aviation hazard in the northern latitudes. In fact, it may be considered a more dangerous event than snow because of the stronger aircraft surface adhesion compared to snow particles. In the winter of 2010/11, the Fog Remote Sensing and Modeling–Ice Fog (FRAM-IF) project was organized near Yellowknife International Airport, Northwest Territories, Canada, with the main goals of advancing understanding of ice fog microphysical and visibility characteristics, and improving its prediction using forecast models and remotesensing retrievals. Approximately 40 different sensors were used to measure visibility, precipitation, ice particle spectra, vertical thermodynamic profiles, and ceiling height. Fog coverage and visibility parameters were estimated using both Geostationary Operational Environmental Satellites (GOES) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations. During this project, the inversion layer usually was below a height of 1.5 km. High humidity typically was close to the ground, frequently producing ice fog, frost, and light snow precipitation. At low temperatures, snow crystals can be swept away by a very low wind speed (∼1 m s−1). Ice fog during the project was not predicted by any forecast model. These preliminary results in the northern latitudes suggest that ice fog and frost studies, over the Arctic regions, can help us to better understand ice microphysical processes such as ice nucleation, visibility, and parameterizations of ice fog.

As an oncoprotein, Eps8 participates in v-Src-induced cellular transformation. To delineate the underlying mechanism, we conducted a yeast two-hybrid screening and identified IRSp53S, a protein critical in cell mobilization, as one of the Eps8-binding partners from a human brain cDNA library. The association was mediated by the multiple proline-rich regions of Eps8 and the C-terminal SH3-WWB containing domains of IRSp53S. In this study, we observed that Eps8 modulated the expression of IRSp53 in v-Src-transformed cells (IV5), raising the question of whether Eps8/IRSp53 interaction was crucial in carcinogenesis. To address this issue, we generated IV5-expressing irsp53 siRNA cells. Attenuation of IRSp53 reduced cell proliferation of IV5 in culture dish and tumor formation in mice, which could be partly rescued by ectopically expressed human IRSp53S. In addition, IRSp53 knockdown impaired activity of phosphatidylinositol 3-kinase (as reflected by Pi-Ser473 AKT) and Stat3 (as reflected by Pi-Tyr705 Stat3), and reduced cyclin D1 expression that culminated to impede G 1 -phase cell-cycle progression. Ectopically expressed human IRSp53S, but not its Eps8-binding defective mutants (that is, Δ363 and PPPDA), rescued these defects and partly restored cell proliferation. Remarkably, through activation of Src, EGF increased the formation of Eps8/IRSp53 complex and Stat3 activation in HeLa cells. With these results, we show for the first time that IRSp53, through its interaction with Eps8, not only affects cell migration but also dictates cellular growth in cancer cells.

Porous metals used as functional materials have been developed greatly and swiftly in recent years. In this paper, some preparative methods and relative applications are reviewed primarily for these materials. These methods concentratively deal with powder metallurgy (PM) and electroplating techniques, and these applications cover filtration and separation, fluid distribution and control, energy absorption, electromagnetic shielding, heat exchangers, electrode matrixes, reaction materials, biomaterials, and so on. copyright 2001 Kluwer Academic Publishers.

Summary Length–weight (LWR) and length–length (LLR) relationships were estimated for 20 species of fish from the upper Yangtze River, southwest China. Samples were collected using multiple types of gear (2–6 cm mesh trammel nets, 2 cm mesh trap nets, and baited hooks) in Jiangjin and Yibin sections from 2007 to 2009. New maximum lengths for 16 species were recorded for FishBase. LWRs were significant for all species. Standard length–total length equations for converting size measurements for these 20 species are also presented. The results provide primary data for future fish research and conservation.

Even though a growing number of studies have found that patients with ankylosing spondylitis (AS) suffer from sexual problems, only very few studies have specifically addressed the relationship between AS and ED. Using a population-based data set, this case–control study aimed to examine the association of ED with a prior diagnosis of AS in Taiwan. We selected 2213 ED patients ⩾40 years old and 17,704 matched controls. We considered the date of the first diagnosis of ED as the index date for cases. Multivariate logistic regression was performed to calculate the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between previously diagnosed AS and ED. A total of 224 out of the 19,917 sampled subjects (1.1%) had been diagnosed with AS before the index date. Prior AS was found in 42 (1.9%) cases and 182 (1.0%) controls. After adjusting for geographic location, urbanization level, hypertension, diabetes, coronary heart disease, hyperlipidemia, obesity, depressive disorder and alcohol abuse/alcohol-dependence syndrome, multivariate logistic regression revealed that cases were more likely to have been previously diagnosed with AS than controls (OR=1.58, 95% CI=1.09–2.19, P =0.019). There was an association between ED and AS. We suggest that physicians should be attentive to sexual complaints from AS patients in order to refer them to other specialists for multidisciplinary management.

As part of the BAQS-Met 2007 field campaign, Aerodyne time-of-flight aerosol mass spectrometers (ToF-AMS) were deployed at two sites in southwestern Ontario from 17 June to 11 July 2007. One instrument was located at Harrow, ON, a rural, agriculture-dominated area approximately 40 km southeast of the Detroit/Windsor/Windsor urban area and 5 km north of Lake Erie. The second instrument was located at Bear Creek, ON, a rural site approximately 70 km northeast of the Harrow site and 50 km east of Detroit/Windsor. Positive matrix factorization analysis of the combined organic mass spectral dataset yields factors related to secondary organic aerosol (SOA), direct emissions, and a factor tentatively attributed to the reactive uptake of isoprene and/or condensation of its early generation reaction products. This is the first application of PMF to simultaneous AMS measurements at different sites, an approach which allows for self-consistent, direct comparison of the datasets. Case studies are utilized to investigate processing of SOA from (1) fresh emissions from Detroit/Windsor and (2) regional aerosol during periods of inter-site flow. A strong correlation is observed between SOA/excess CO and photochemical age as represented by the NOx/NOy ratio for Detroit/Windsor outflow. Although this correlation is not evident for more aged air, measurements at the two sites during inter-site transport nevertheless show evidence of continued atmospheric processing by SOA production. However, the rate of SOA production decreases with airmass age from an initial value of ~10.1 μg m−3 ppmvCO−1 h−1 for the first ~10 h of plume processing to near-zero in an aged airmass (i.e. after several days). The initial SOA production rate is comparable to the observed rate in Mexico City over similar timescales.

Conditional distributivity of aggregation functions, which has received wide attention from the researchers, is vital for many different fields, for example, integration theory, utility theory and so on. This article is mainly devoted to dealing with the conditional distributivity of continuous t-norms over 2-uninorms. As the first step for investigating the conditional distributivity of 2-uninorms, we give the complete characterization of all pairs $(T,\\mathcal{H})$ {fulfilling} this property. Compared to the case of distributivity of continuous t-norms over 2-uniorms, which leads to the 2-uninorm must be idempotent, the results obtained in this paper demonstrate that conditional distributivity and distributivity on this topic, are not equivalent.

D-phenylalanine (D-Phe) is an important side-chain building block for semi-synthetic penicillins and cephalosporins. To synthesize D-Phe, D-amino acid aminotransferases (Dat) from Bacillus subtilis WB600, Bacillus licheniformis ATCC 14580, and Bacillus amyloliquefaciens were firstly compared. The theoretical 3 dimensional models of Dat were constructed, which showed appropriate configuration for synthesis of D-Phe in virtual screening. The comparison 3 different Dat on D-Phe formation was tested. All the heterogenous Dat showed high thermostability and pH stability, while Dat from B. subtilis demonstrated a better potential for Phe production than those from B. licheniformis and B. amyloliquefaciens. Then the dat from B. subtilis was expressed in an L-Phe producing chassis of Escherichia coli W14 (pR15ABK) to obtain D-Phe and different factors affecting D-Phe accumulation were tested. The engineered strain E. coli BCEA (pR15ABKApRdatBS) accumulated 1.72 g/L D-Phe in a 15-L jar fermenter which is the highest fermentation concentration that had been reported.