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By exposing floating gates of EEPROM memory cells with frontside sample preparation, scanning nonlinear dielectric microscopy (SNDM) succeeded in reading back the data stored in the memory cells with a 250 nm node size. At an optimized voltage bias of AC = 3 V and DC = 1 V, a clear signal contrast between programmed and erased cells is obtained. The high resolution SNDM signal reveals the details of bowling-pin shape structure of memory cells, providing high confidence in data assignment during forensic applications. Such high resolution also makes SNDM a promising technique for newer generation devices with smaller node size. [ABSTRACT FROM AUTHOR]

A custom-built gas cluster ion source with an energy up to 20 keV is constructed. Ar, CO2, N2, and O2 are used as the working gases. The clusters are formed by metal conical nozzles with critical diameters of 65−135 um and a cone angle of 14°. To facilitate evacuation of the chambers we use the pulse mode of nozzle feeding. This allows an increase in the gas pressure in the stagnation zone (inlet pressure) up to 15 bar. The current of the clusters with an energy of 20 keV is 20 µA; the maximal current density is 3 µA/cm2. The mass spectra of the argon clusters formed at different pressures and electron ionization energy are studied by time-of-flight spectroscopy. The inlet pressure dependence of the mean cluster size is considered as a function of the condensation parameter Г*. An argon cluster beam is used to smooth the surface of the titanium coating and pressed silicon nanopowder. The roughness of the Ti coating surface decreases from 3.7 to 0.8 nm; the removal of microparticles from the surface is also observed. In the case of the surface of Si, besides the smoothing effect the formation of 100 nm craters is observed. [ABSTRACT FROM AUTHOR]

This study proposes the generality of surface air temperature ( SAT)-atmospheric circulation feedback during high-temperature weather in late July 2003 over East China by using the Advanced Research Weather Research and Forecasting model ( WRF; Version 3) simulations with a succession of 24-h integrations, i.e. on a daily scale, the SAT increase leads to a weakened ridge of the western Pacific subtropical high in the lower troposphere (i.e. negative feedback), whereas it leads to a strengthened ridge in the upper troposphere (i.e. positive feedback) and vice versa. Additionally, using the balance equation of temperature, the feedbacks are clarified from the diurnal-variation perspective. This shows many complex details, e.g. the changes in geopotential heights are more complex than those in air temperatures, and the overall daily feedback appears to be dominated by the feedback during the phase with intense daytime surface heating. All of the WRF-modified land surface conditions can lead to large changes in the maximum, minimum, and average SATs over the mean diurnal scale, with generally larger differences induced by land surface schemes than those induced by initial soil moisture, suggesting that the SAT-circulation feedback can be greatly reduced (or amplified) by different land conditions over the diurnal weather scale and that diurnal variations could substantially contribute to longer timescale climate. [ABSTRACT FROM AUTHOR]

The Sichuan-Chongqing area in China has complex basin topography and is known for its extremely hot summer weather. In this paper, the mesoscale model WRF version 3.6.1 was used to simulate a period of 1–10 days in advance of the hot weather that occurred in Sichuan-Chongqing on August 10, 2006, to investigate the effect of six different land surface schemes (LSSs) (SLAB, RUC, PX, NOAH, NOAH_MP, and CLM4) on short- and medium-range simulations of high temperatures. The simulated surface air temperatures (SATs) are sensitive to the LSSs and simulation lengths. Specifically, all of the LSSs except PX generally reproduce the observed high temperatures, with CLM4 SATs at 06 UTC (SAT06) the most consistent with measurements whereas the short-range (medium-range) results from NOAH_MP (NOAH) are the worst. Detailed explanations were given in terms of surface fluxes and physical processes. RUC soil moisture initialization appears poor and the LSS reflects too strong gravity drainage. When the LSSs with increased numbers of soil layers are used, the simulated high temperatures are found more consistent with measurements. Additionally, regional sensible heat flux (SHF) does not show high consistency with SAT. The results that differ from the previous studies are partly due to the complex geography and the LSS deficiencies. [ABSTRACT FROM AUTHOR]

We obtain an exact estimate for the first-order absolute moment of Stancu Beta operators by means of the Stirling formula and integral operations. Then we use this estimate for establishing a theorem on approximation of absolutely continuous functions by Stancu Beta operators. [ABSTRACT FROM AUTHOR]

AKT pathway has a critical role in mediating signaling transductions for cell proliferation, differentiation and survival. Previous studies have shown that AKT activation is achieved through a series of phosphorylation steps: first, AKT is phosphorylated at Thr-450 by JNK kinases to prime its activation; then, phosphoinositide-dependent kinase 1 phosphorylates AKT at Thr-308 to expose the Ser-473 residue; and finally, AKT is phosphorylated at Ser-473 by several kinases (PKD2 and others) to achieve its full activation. For its inactivation, the PH-domain containing phosphatases dephosphorylate AKT at Ser-473, and protein serine/threonine phosphatase-2A (PP-2A) dephosphorylates it at Thr-308. However, it remains unknown regarding which phosphatase dephosphorylates AKT at Thr-450 during its inactivation. In this study, we present both in vitro and in vivo evidence to show that protein serine/threonine phosphatase-1 (PP-1) is a major phosphatase that directly dephosphorylates AKT to modulate its activation. First, purified PP-1 directly dephosphorylates AKT in vitro. Second, immunoprecipitation and immunocolocalization showed that PP-1 interacts with AKT. Third, stable knock down of PP-1α or PP-1β but not PP-1γ, PP-2Aα or PP-2Aβ by shRNA leads to enhanced phosphorylation of AKT at Thr-450. Finally, overexpression of PP-1α or PP-1β but not PP-1γ, PP-2Aα or PP-2Aβ results in attenuated phosphorylation of AKT at Thr-450. Moreover, our results also show that dephosphorylation of AKT by PP-1 significantly modulates its functions in regulating the expression of downstream genes, promoting cell survival and modulating differentiation. These results show that PP-1 acts as a major phosphatase to dephosphorylate AKT at Thr-450 and thus modulate its functions. [ABSTRACT FROM AUTHOR]

Toll-like receptor 4 (TLR4) is a member of the Toll-like receptor family, which can bridge innate and adaptive immune responses. Activation of the TLR4 signalling pathway may induce the release of proinflammatory cytokines such as tumour necrosis factor (TNF)-α and interleukin (IL)-12, which was considered to play an important role in pathogenesis of immune-mediated diseases. Ankylosing spondylitis (AS) is an immune-mediated disease whose aetiology remains unknown. The aim of the study was to investigate the expression of TLR4 and serum TNF-α, IL-12 and soluble tumour necrosis factor-related apoptosis-inducing ligand (sTRAIL) level in AS patients. The results indicated that TLR4 protein and mRNA levels were significantly higher in AS patients than in healthy controls; however, there was no significant difference between human leucocyte antigen (HLA)-B27-positive and -negative AS patients, as well as serum levels of TNF-α, IL-12 and sTRAIL. In addition, in HLA-B27-positive AS patients, TLR4 level showed close associations with the cytokines and laboratory parameters of disease activity [erythrocyte sedimentation rate (ESR) and plasma C-reactive protein (CRP)], respectively. Similarly, the strong associations between the cytokines or between IL-12 and ESR or CRP were observed in HLA-B27-positive AS patients. Interestingly, in HLA-B27-positive AS patients, TNF-α correlated significantly with ESR, but did not with CRP. In contrast, sTRAIL correlated with CRP, but did not with ESR. Among HLA-B27-negative patients, no close correlation was found. In our study, it was suggested that the abnormal activation of TLR4 signalling and serum TNF-α, IL-12 and sTRAIL may play a key role in the development and progression of AS, which may be dependent on the status of HLA-B27 antigen. [ABSTRACT FROM AUTHOR]

¶In order to further understand the land–atmosphere interactions and increase the predictability of climate models, it is very important to investigate the effects of land-surface heterogeneities. In this paper, we considered roughness-length and stomatal-resistance heterogeneities in the regional climate model RegCM2 (Giorgi et al., 1993) that employs BATS (Dickinson et al., 1993) as the land surface scheme. In representing the subgrid heterogeneities, a computationally efficient method, which is a combination of the mosaic approach and the analytical type of the statistical-dynamical approach, is applied. The method is also characterized by converting the probability distribution of fundamental variables to probability distributions of derived quantities. By using the 3-month observational data of 1991 Meiyu season over China, we conducted coupled-model experiments, and found that: (i) For the whole model domain, the consideration of the two heterogeneities, in which intrapatch variability plays a very important role, greatly affects the simulations for the surface flux, wind, temperature and precipitation fields. (ii) The temperature and heat fluxes are quite sensitive to the heterogeneities, which displays the following rule: for a sub-region, the mean sensible heat flux decreases, the mean latent heat flux increases, and the mean surface temperature decreases with the increase of the heterogeneities. Furthermore, the mean latent heat flux is more sensitive to the heterogeneities than the mean sensible heat flux. (iii) It seems that the influence of stomatal-resistance heterogeneity on the latent heat flux is greater than that of roughness-length heterogeneity. Therefore, it is necessary to appropriately represent subgrid land-surface heterogeneities so as to improve regional climate modeling. [ABSTRACT FROM AUTHOR]