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Antigorite dehydration is well known as a key process at convergent boundaries for the genesis of mantle wedge partial melting and intermediate‐depth earthquakes. However, the crystallographic preferred orientations (CPOs) of prograde minerals from antigorite dehydration and their effects on the seismic anisotropy of subducting slabs remain ambiguous and controversial. Here we report antigorite dehydration experiments on a foliated serpentinized peridotite at pressures of 0.3–6 GPa and temperatures of 700–900°C. Our results show that olivine CPO evolves from a fiber‐[100] type in fine grains to a type‐C like in coarse grains. We propose that the fiber‐[100] olivine CPO is developed by topotactic growth during incipient hydrostatic dehydration, while the orthorhombic type‐C like olivine CPO is developed by anisotropic growth resulting from an anisotropic fluid flow during later dehydration. The type‐C like olivine CPO in the antigorite‐rich layers after antigorite dehydration could contribute to the trench parallel fast shear wave seismic anisotropy at convergent plate boundaries. Plain Language Summary: We study the crystallographic preferred orientations and seismic anisotropies of dehydrated antigorite samples. Our results show that the CPOs of prograde mineral, olivine, evolve from the fiber‐[100] CPO in fine grains to the type‐C like CPO in coarse grains. The type‐C like olivine CPO after antigorite dehydration could cause trench‐parallel fast shear wave seismic anisotropy observed at convergent plate boundaries. Key Points: Olivine crystallographic preferred orientations (CPO) evolves from the fiber‐[100] CPO to the type‐C like CPO with increasing grain size during hydrostatic dehydration of antigoriteThe fiber‐[100] and type‐C like olivine CPOs are developed by topotactic growth and anisotropic growth, respectivelyThe prograde olivine with type‐C like CPO could contribute to trench parallel seismic anisotropy at convergent boundaries [ABSTRACT FROM AUTHOR]

One of the main issues of space weather is the timely prediction of disturbed solar wind parameters at L1, especially caused by Coronal Mass Ejection (CME). Using the data from 170 front halo, flare‐associated CMEs, and in‐site solar wind data, an analysis of the Interplanetary Coronal Mass Ejection (ICME) peak velocity at L1 related to associated coronal parameters is performed. The statistical methods including the Generalized Additive Modeling (GAM) and Multiple Collinear (MC) have been applied to explain the underlying physical reasons and set up a new prediction model. Our results indicate that (1) X‐flare integral flux, CME linear velocity, and Acceleration observed on corona play key roles in ICME velocity, while other coronal parameters only present a weak correlation, such as the CME Mass and Angular Width, (2) the relationship between ICME velocity and CME Acceleration, as well as CME linear velocity, is nonstationary, and the ICME velocity will increase with the increasing CME Acceleration or linear velocity until saturation, and (3) MC is an effective method to improve the forecast model performance. Compared with 0.52 for only GAM, the correlation coefficient using GAM + MC reaches to 0.71. To further testify the prediction ability, the GAM + MC model results are compared with the Back‐Propagation network model and a typically empirical statistic relation proposed by Manoharan (2006, https://doi.org/10.1007/s11207-006-0100-y; their correlation coefficients and root mean squared errors are both roughly 0.6 and 100 km/s, respectively). It is found that the MC + GAM can upgrade the forecast at least over 10%. Key Points: Generalized Additive Modeling and Multiple Collinear are used to forecast ICME velocity at L1Multiple Collinear is an effective method to improve a forecast model performanceGeneralized Additive Modeling and Multiple Collinear can upgrade the forecast over 10% [ABSTRACT FROM AUTHOR]

A zirconium- and Cr(III)-containing conversion coating on Al alloy 2024-T3 was prepared in solution containing Cr2(SO4)3 and K2ZrF6. Its composition was analyzed by energy dispersive X-ray spectrometry (EDS), and its corrosion resistance was investigated using polarization curve, electrochemical impedance spectroscopy (EIS), and salt spray exposure. An artificial scratch cell was used to investigate its 'self-repairing' effect by EIS and X-ray photoelectron spectroscopy (XPS). In addition to Al, the conversion coating contained Zr, Cr, O, and F. The conversion coating provided obvious corrosion protection for the Al alloy 2024-T3. The EIS measurement and corrosion morphology observation of bare samples (i.e., uncoated samples) in the artificial scratch cell confirmed that the conversion coating possessed 'self-repairing' effect. XPS analysis showed that Cr(III) species, but not Zr species were transported from the conversion coating to the nearby bare area as in a scratch. [ABSTRACT FROM AUTHOR]

The intergranular corrosion (IGC) sensitivity of an Al-3.81Cu-1.28Li-X alloy with T6 aging for different time at 150, 175, and 200 °C was investigated. With aging, the alloy potential lowers due to precipitation, accompanied with coarsening and discontinuous distribution of grain boundary precipitates, which contributes to corrosion evolution with aging time. Corrosion mode evolution with aging stage (corresponding to hardness evolution) at aging temperature of 150 and 175 °C follows the following order: pitting and local IGC (early aging), general IGC (under-aged), local IGC with pitting (near peak-aged), and pitting (over-aged). At elevated aging temperature of 200 °C, the corrosion mode evolves much faster. IGC only appears in the intensively under-aged stage, but the later under-, peak-, and over-aged stage are featured with pitting corrosion. As IGC occurs, its depth is initially increased and then decreased with aging time. [ABSTRACT FROM AUTHOR]

The Volta potential change and corrosion behaviors of alloys Al-0.63Mg-0.28Si and Al-0.52Mg-0.63Si under MgCl2 drops with the initial concentration of 0.1-1.0 M in environments with relative humidity (RH) 33% were studied using a Kelvin probe (KP). For the alloy Al-0.63Mg-0.28Si, the Volta potential curve was mainly featured with many potential transients in the form of a sudden drop followed by an immediate recovery along the potential baseline at a higher potential value of −0.35 to −0.5 VSHE, which were associated with initiation and repassivation of metastable pits with diameter less than 3 μm. For the alloy Al-0.52Mg-0.63Si containing excess Si particles, the potential curve was featured with potential change in the form of slow increase followed by a sudden drop along the potential baseline at a lower potential value of about −0.7 VSHE. The sudden potential drop and stabilizing at the lower potential level were associated with corrosion initiation and growth, respectively. In the case of lower initial concentration and higher Si content leading to excess Si particles, the corrosion rating was higher. However, the excess Si particles showed a greater impact than the initial concentration. [ABSTRACT FROM AUTHOR]

The corrosion behavior of an Al-0.63Mg-0.28Si alloy under MgCl2 solution droplets with different initial concentration in environments of 33, 75, and 88% relative humidity (RH) was studied using a Kelvin probe. The available cathodic limiting current associated with oxygen reduction was highly dependent on the environment RH and initial concentration. In the 33% RH environment, metastable pitting was the main form of corrosion. In some cases at 75 and 88% RH, the potential baseline decreased slowly by hundreds of mV and remained at the lower value, indicating stable filiform-like corrosion grew. The initiation time of the stable corrosion was determined by the environment RH and initial concentration. With increasing initial concentration or decreasing environment RH, the available cathodic limiting current decreased, stable corrosion was difficult to occur. The stable corrosion could occur outside the drop and/or inside the drop, which was dependent on not only the cathodic limiting current but also the environment RH. [ABSTRACT FROM AUTHOR]

Ni-Si3N4 nanocomposite films with both the consecutive Ni crystallites and dispersed Si3N4 particles in the nanometer range have been fabricated using DC electroplating technique, and characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), and X-ray diffraction (XRD). The corrosion resistance of the Ni-Si3N4 nanocomposite film has been compared to that of pure Ni coating through polarization. Meanwhile, the corrosion process of Ni-Si3N4 nanocomposite film in neutral 3.5% NaCl solution has been investigated using electrochemical impedance spectroscopy (EIS). The results show that the Ni-Si3N4 nanocomposite film is more resistant to corrosion than the pure Ni coating. The corrosion of Ni-Si3N4 nanocomposite film is controlled by electrochemical step, and the whole corrosion process is divided into two sequential stages. The main corrosion type of Ni-Si3N4 nanocomposite films in neutral 3.5% NaCl solution is pitting. [ABSTRACT FROM AUTHOR]

In recent years, the role of high mobility group box-1 (HMGB1) protein and its receptors in autoimmune diseases has received increasing attention. It has been documented that HMGB1 is associated with disease activity in patients with systemic lupus erythematosus (SLE). This study was undertaken to determine the potential role of receptor for advanced glycation end products (RAGE), one receptor for HMGB1, in the pathogenesis of SLE. Plasma levels of soluble RAGE (sRAGE) from 105 patients with clinical diagnosis of SLE and 43 healthy controls were determined by ELISA. Associations between sRAGE levels and clinical, laboratory characteristics were assessed. The data showed that plasma levels of sRAGE in patients with SLE were significantly lower than those in healthy controls (HC) ( P = 0.003). Plasma sRAGE in patients receiving short-period treatment showed an immediate decrease compared with the untreated patients ( P = 0.023). In contrast, plasma sRAGE in patients receiving long-period treatment were significantly increased compared to those with short-period treatment ( P = 0.000) and comparable with those in HC ( P = 0.305). The significant decreased levels of sRAGE in patients with SLE suggest the potential association of RAGE signalling and SLE clinical pathology, whereas, long-period antilupus treatment may counteract the decreased sRAGE levels in patients with SLE. [ABSTRACT FROM AUTHOR]

In this study, the complementary DNA (cDNA) of Japanese pufferfish Takifugu rubripes tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) was cloned by reverse-transcription PCR. The open reading frame of the TRAIL consisted of 870 bases. The deduced amino-acid sequence of the TRAIL showed a high homology with the sequences of other teleosts. Recombinant soluble TRAIL was fused with a small ubiquitin-related modifier gene to enhance the soluble expression level in Escherichia coli BL21 (DE3). In vitro, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) assay indicated that the purified soluble TRAIL was able to induce apoptosis of Jurkat and HeLa cells in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Four new chiral 4-substituted 5,5-diethyl oxazolidin-2-ones ( 5a–5d) as potential effective chiral auxiliaries were synthesized from readily available amino acids via asymmetric etherification, Boc protection, Grignard reaction and cyclization reactions in four steps with overall yields of 50–60%. [ABSTRACT FROM AUTHOR]

Prolonged swimming performances of two as yet unnamed species of three-spined stickleback, Gasterosteus spp., were compared. The two fishes (not yet formally described, referred to here as benthic and limnetic) inhabit different niches within Paxton Lake, Texada Island, British Columbia, Canada, and are recent, morphologically distinct species. Limnetics had longer endurance during prolonged swimming than did benthics. The mean regression of the log10 of fatigue time ( Ft, s) on swimming speed ( U, standard length, LS s−1) for limnetics (log10 Ft = 7·03 − 0·46 U) had a similar slope, but a significantly higher intercept than that for benthics (log10 Ft = 5·55 − 0·43 U). Adult benthics were larger, heavier and deeper-bodied fish than limnetics. Limnetics, however, had a significantly greater pectoral fin edge:base ratio (mean ± s. e.: limnetics, 4·58 ± 0·43; benthics, 3·63 ± 0·27). In addition, limnetics had significantly lower drag coefficients ( CD) than benthics (limnetics, log10 CD = −0·49log10 R e + 0·66; benthics, log10 CD = −0·26log10 R e − 0·30) where R e is the Reynolds number [( LS U (ν−1), where U and ν are swimming velocity and the kinematic viscosity of the water, respectively]. Compared to their ancestral form, the anadromous three-spined stickleback Gasterosteus aculeatus L., limnetics and benthics had significantly longer and shorter endurance times, respectively. In addition, both these fishes had significantly higher fast-start velocities than their ancestral form. Selection due to differential resource use may have lead to divergence of body form, and, therefore, of steady swimming performance. Therefore predation may be the selective force for the similar high escape performance in these two fishes. [ABSTRACT FROM AUTHOR]

A two-element ultra wideband array antenna with a 5.8 GHz band-notch function is proposed. A novel Marchand balun feeding structure is chosen for its great merit of the equi-amplitude and 180° phase difference signals, making the omni-directional of radiation pattern much better. A simple u-shape slot is inserted into the radiating patch to create a frequency band-stop characteristic. The measured VSWR less than 2 is from 3.1 to 10.6 GHz, and the frequency notch band is from 5.7 to 5.9 GHz. The measured results agree well with the simulated. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1537–1539, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24384 [ABSTRACT FROM AUTHOR]