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The chiral enantiomeric transition of bis-α-alanine chelated Cu(ii) complexes (α-Ala)2-Cu(ii) was investigated for the first time using the M06 and MN15 methods combined with the SMD model approach.

Bioaerosol concentrations in residential buildings located in the Northeastern US have not been widely studied. Here, in 2011-2015, we studied the presence and seasonal variability of culturable fungi and bacteria in three multi-family apartment buildings and correlated the bioaerosol concentrations with building ventilation system types and environmental parameters. A total of 409 indoor and 86 outdoor samples were taken. Eighty-five percent of investigated apartments had indoor-outdoor (I/O) ratios of culturable fungi below 1, suggesting minimal indoor sources of fungi. In contrast, 56% of the apartments had I/O ratios for culturable bacteria above 1, indicating the prominence of indoor sources of bacteria. Culturable fungi I/O ratios in apartments serviced by central heating, ventilation, and air-conditioning (HVAC) system were lower than those in apartments with window AC. The type of ventilation system did not have a significant effect on the presence of indoor culturable bacteria. A significant positive association was determined between indoor dew point (DP) levels and indoor culturable fungi (P

Autosomal dominant polycystic kidney disease (ADPKD) is mainly caused by mutations in the PKD1 (~85%) or PKD2 (~15%) gene which, respectively, encode polycystin-1 (PC1) and polycystin-2 (PC2). How PC1 regulates cell proliferation and apoptosis has been studied for decades but the underlying mechanisms remain controversial. Protein kinase RNA-activated (PKR) is activated by interferons or double-stranded RNAs, inhibits protein translation, and induces cell apoptosis. In a previous study, we found that PC1 reduces apoptosis through suppressing the PKR/eIF2α signaling. Whether and how PKR is involved in PC1-inhibited proliferation and protein synthesis remains unknown. Here we found that knockdown of PKR abolishes PC1-inhibited proliferation and translation. Because suppressed PKR-eIF2α signaling/activity by PC1 would stimulate, rather than inhibit, the proliferation and translation, we examined the effect of dominant negative PKR mutant K296R that has no kinase activity and found that it enhances the inhibition of proliferation and translation by PC1. Thus, our study showed that inhibition of cell proliferation and protein synthesis by PC1 is mediated by the total expression but not the kinase activity of PKR, possibly through physical association.

In this work, a new process is developed to improve the functional stability of Ni-rich NiTi alloys. Repetitive temperature- and stress-induced phase transformation is first conducted to generate dislocation networks in the grain interior. Dislocations serve as nucleation sites for Ni₄Ti₃ nanoprecipitates, which are formed after subsequent low-temperature (523 K) aging. With the presence of dislocations, a homogeneous distribution of nanoprecipitates in the grains is expected, enhancing the strength of the NiTi matrix and resisting plastic deformation during the martensitic transformation. As a result, an improved functional stability of NiTi alloys is achieved. ispartof: Scripta Materialia vol:163 pages:57-61 status: published

Considering individual variability in regards to the effects of orthokeratology (ortho-k) on myopia progression and controversies regarding the precise underlying mechanism, the aim of this study was to investigate several ocular measurements associated with axial length (AL) growth in children wearing ortho-k lenses.In this retrospective chart review, medical records of 53 Chinese children who wore ortho-k lenses over the course of 12 months were reviewed. Baseline variables included age at initiation of ortho-k wear, refractive error (spherical equivalent, SE), central corneal thickness (CCT), and flat and steep keratometry of corneal principal meridians. The change of anterior chamber depth (ACD) and the change of crystalline lens thickness (CLT) between baseline and the 12-month follow-up were also analyzed. The contributions of all analyzed variables to AL change were assessed using univariate and multivariate regression analyses.Initially, the results of paired t-test showed that CLT and AL were significantly increased after 12 months of ortho-k wear compared with that at baseline (P = 0.001 and 0.001). The ACD did not change significantly after 12 months compared with that at baseline (P = 0.491). Subsequently, univariate analyses showed that a reduced rate of AL elongation was found in children who were older age at initiation of ortho-k wear (P = 0.028), had greater SE (higher degree of myopia) at baseline (p = 0.006), had thicker CCT at baseline (P = 0.04), and had greater increase of CLT (P = 0.001) in 12 months. At last, only greater SE (higher degree of myopia) and greater increase of CLT were associated with smaller increases of AL in multivariable analyses, (P = 0.003 and 0.001).Both CLT and AL were significantly increased in children with overnight ortho-k wear after 12 months of follow-up. Greater baseline SE and greater increase of CLT were associated with less increase in AL during ortho-k wear in children with myopia.

X-ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry were combined to characterize the surface oxides (native oxides and passive films) formed on Ni-based alloys containing chromium and molybdenum. Two alloys were studied, Ni-20Cr and Ni-20Cr-10Mo (in wt.%). For Ni-20Cr, both native oxide and passive films formed in acidic medium present a duplex structure comprising a Ni and Cr outer hydroxide layer and a Cr inner oxide layer. The Ni-20Cr-10Mo alloy presents a similar bilayer structure, but with Mo oxide located at the outer layer/inner layer interface. Cr enrichment is observed after passivation for both alloys. The corrosion resistance in acidic solution containing chlorides is enhanced by Mo, and by electrochemical pre-passivation in Cl free solution.

Exposure to bioaerosols has been implicated in adverse respiratory symptoms, infectious diseases, and bioterrorism. Although these particles have been measured within residential and occupational settings in multiple studies, the deposition of bioaerosol particles within the human respiratory system has been only minimally explored. This paper uses real-world environmental measurement data of total fungal spores using Air-o-Cell cassettes in 16 different apartments and residents' physiological data in those apartments to predict respiratory deposition of the spores. The airborne spore concentrations were measured during the spring, summer, and fall. The respiratory deposition of five most prevalent spore genera-Ascospores, Aspergillus, Basidiospores, Cladosporium, and Myxomycetes-was predicted using three empirical models: the Multiple Path Particle Dosimetry model, using both the Yeh and age-specific versions, and the Bioaerosol Adaptation of the International Committee on Radiological Protection's Lung deposition model. The predicted total deposited number of spores was highest for Ascospores and Cladosporium. While the majority of spores deposit were in the extrathoracic region, there is a significant deposition for both Aspergillus and Cladosporium in the alveolar region, potentially leading to the development of aspergillosis or allergic asthma. Although the dose-response relationship is unknown, the estimate of the actual spore deposition could be the first step in determining such a relationship.

We use first-principles density functional theory and ab initio molecular orbital theory to study the chiral transition process of the serine molecule and explore the roles of water, hydroxyl radical and hydroxide ion as catalysis during the interconversion process. The two most plausible chiral transition pathways of isolated serine are identified, in which α-hydrogen is transferred using the amino N atom as a bridge rather than the carbonyl O atom. These two chiral transition mechanisms involve the transformation of chiral enantiomers; in other words, they are serine enantiomerization. Two proton transfer steps with high energy barriers of ∼58.0 and 37.0 kcal mol−1 are the rate-limiting steps. The calculations show that water can effectively catalyze the chiral transition by facilitating efficient proton transport, and the highest energy barriers are ∼26.4 and 4.8 kcal mol−1. The calculations also predict that hydroxyl radical can further lower the energy barriers of the chiral transition to approximately 12.6 and 5.3 kcal mol−1 by facilitating proton transfer. In contrast, hydroxyl radical is more likely to damage serine, and the damage is difficult to repair. Finally, hydroxide ion can further reduce the barriers to chiral transition to approximately 5.5 and 4.5 kcal mol−1 by facilitating proton transfer. As far as we know, this is the first time that these important roles of water, hydroxyl radical and hydroxide ion in serine chiral transition have been demonstrated. The findings provide new insights into the mechanism of serine enantiomerization at the atomic level. Meanwhile, the results show that hydroxyl radical can damage serine, and the damage is difficult to repair.

Thermal stability of surface oxides on Ni-20Cr and Ni-20Cr-10Mo alloys, including air formed native oxides and passive films formed by electrochemical passivation, was investigated by stepwise heat treatments in ultra-high vacuum up to 300 °C. The modifications of the surface oxides were analyzed by XPS and in situ ToF-SIMS. The analytical surface characterization at the nanoscale revealed modifications of the protective surface oxides that depend on temperature and nature of the alloy. A loss of Ni(OH)2 in the outer hydroxide layer and a decrease of film thickness are observed on both alloys above 100 °C. At 200 °C, Ni hydroxide in the outer layer is no longer stable while MoO3 decreases and MoO2 increases in the oxide film. At 300 °C no native oxide film remains at the surface of Ni-20Cr alloy, whereas a thin Cr oxide film partially covering the surface remains on passivated Ni-20Cr and for both native and passivated surfaces of Ni-20Cr-10Mo alloy. It is shown that the thermal stability of the surface oxide is significantly improved by electrochemical passivation on both alloys and is further enhanced by the presence of Mo in the oxide on the Mo-containing alloy. Such findings are useful for the development of corrosion protection strategies.

V-4Cr-4Ti alloy, one of the promising candidate structural materials for fusion first wall/blanket applications, was annealed in different temperatures (800 °C and 1000 °C) followed by hydrogen and subsequent helium ions irradiation. It is designed for ion irradiations by forming different size of precipitates, intending to investigate the effect of interfacial coherency characteristic on the irradiation damage behavior at an atomic scale. The microstructure was studied by transmission electron microscopy and the effect of irradiation hardening was evaluated by nanoindentation technique. The results show that TiC precipitate with different size and density was formed during the heat treatment. The lattice matching and the resulting strain state at the interface between the precipitate and the matrix were also investigated quantitatively. The samples with large precipitate exhibited a relatively lower irradiation hardening rate than the one with smaller precipitate, which attributes to the distinct aggregation of He atoms at the interface between the larger precipitate and vanadium alloy matrix. It suggests that the strain state at the interface between the precipitate and the matrix plays a key role in determining the distribution state of irradiation defects thus affect the irradiation damage behavior significantly.

To enhance the anti-friction and anti-wear properties of the WC/TiC/Co carbide, micro-EDM was selected to fabricate textured micro-holes on the carbide surface, and graphite was embedded into the micro-holes to form self-lubricating tools. Dry machining tests on AISI 1045 hardened steel were carried out with the self-lubricating tool and conventional ones. The cutting temperature and tool wear were investigated and compared. The results showed that the self-lubricating tool embedded with graphite exhibited excellent efficiency and stability in reducing cutting temperature, and then the tool wear was reduced compared to that of the conventional one. Through the analysis of test results and cutting temperature distribution theory, the mechanisms responsible are put forward: the first one is the formation of a graphite film on the tool rake face, which is conducive to reducing the temperature of chip and tool caused by tool-chip friction and chip deformation; the other one is attributed to the reduced actual contact length at the tool-chip interface due to the micro-holes, which is propitious to lower the temperature of chip and tool caused by tool-chip friction, supply more graphite, and store chip debris.

To improve the tribological properties of the cemented carbide, Ti–MoS2/Zr composite coatings were deposited on the substrate surface by medium-frequency magnetron sputtering coupled with multi-arc ion plating. The morphology and fundamental properties of the coatings were examined. Dry machining test on AISI 1045 hardened steel was carried out with the coated tool and uncoated tool. The variation of cutting temperature was tested by a TH5104 thermo tracer. The results showed that cutting speed had a profound effect on the cutting temperature. In low-speed cutting of less than 120 m/min, the cutting temperature was decreased by 18–22% and flank wear resistance was improved by 25–30% in comparison with that of uncoated tool, while in high-speed cutting, there was not much difference in cutting performance owing to the high temperature caused by the elevated cutting speed. Through the analysis of cutting heat distribution theory, two responsible mechanisms are found: as lubricating additive between the tool and chip sliding couple, the Ti–MoS2/Zr composite coatings contribute to the decrease of average shear stress on the rake face and the thermal barrier effect in heat conduction. These may result in the decrease of the cutting temperature of tool and chip, and hence the improvement of tool wear resistance.

International audience; An approach preventing contact to ambient air during transfer from liquid environment for electrochemical treatment to UHV environment for surface analysis by X-Ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry was applied to study the mechanisms of Cr and Mo enrichments in the passive oxide film formed on 316L austenitic stainless steel. Starting from the air-formed native oxide-covered surface, exposures were conducted in aqueous sulfuric acid solution first at open circuit potential and then under anodic polarization in the passive range. At open circuit potential the thickness of the bi-layered oxide film was observed to decrease and the enrichments of both Cr(III) and Mo, mostly Mo(VI), to markedly increase as well as the film hydroxylation. This is due to preferential dissolution of the Fe(III) oxide/hydroxide, not compensated by oxide growth in the absence of an electric field established by anodic polarization. Anodic polarization in the passive domain causes the bi-layered structure of the oxide film to re-grow by oxidation of iron, chromium and molybdenum, without impacting the Cr enrichment and only slightly mitigating the Mo enrichment. De-hydroxylation of the inner layer is also promoted upon anodic polarization. These results show that the treatment of the surface oxide film in acid solution at open circuit potential enhances Cr and Mo enrichments and promotes hydroxylation. Passivation by anodic polarization allows dehydroxylation, yielding more Cr oxide, without markedly affecting the Mo enrichment, also beneficial for the corrosion resistance.

In order to meet the requirements of miniaturization and low cost of rolling missiles, the roll-isolated strapdown inertial navigation systems began to be applied to such weapon systems. This paper proposes an adaptive control approach based on LuGre friction torque model to eliminate the influence of the nonlinear characteristics of the friction torque of the roll-isolated platform at low speed. Two nonlinear state observers are used to estimate the unknown state variables in LuGre model, and the parameters of the model are adaptively estimated. The global asymptotic stability of the system is proved by Lyapunov method. The simulation results show that compared with the traditional control approaches, this approach improves the control precision and low-speed performance of the roll-isolated platform, and can meet the performance requirements of the roll-isolated strapdown inertial navigation system.

In this work, a feasible method to improve the mechanical performance of laser powder bed fusion (L–PBF) fabricated AlSi10Mg alloy has been developed by the addition of Al Ti C B master alloy powders into AlSi10Mg alloy powders. During L–PBF process, the Al Ti C B alloy powders could release numerous sub–micron and nanosized B atoms doped TiC (TiCB) particles, which will act as the in–situ nucleation sites for α–Al grains. A textureless microstructure consisting of equiaxed α–Al grains with average size of 3 μm was obtained in the L–PBF fabricated AlSi10Mg alloy decorated with 10 wt.% of Al Ti C B alloy powders (AlSi10Mg TiCB). Fine Al Si cellular structure composed of small eutectic Si particles (~30 nm) was also detected. Besides, the nano–sized Si precipitates (~10 nm) distributed uniformly inside the α–Al grains were also observed. The L–PBF fabricated AlSi10Mg TiCB alloy exhibits high ultimate tensile strength of 488 ± 6 MPa and total elongation of 10.1 ± 2.2%. The enhanced mechanical properties are supposed mainly attributing to the significant refinement of α–Al grains and Al Si eutectic cells due to the addition of TiCB inoculants, as well as the particles reinforcement effect by TiCB and Si precipitates. The method proposed in this work is promising, since it is easy to operate, which requires only mechanically mixing two Al–based powders. This work may also provide new insights for designing Al alloy powders suitable for L–PBF process, using particle–contained Al–based master alloys to decorate other commercial powders, such as 2 × × × and 7 × × × series alloys.

In this work, we proposed a process to improve the functional stability of Ni-rich NiTi alloys, which combines surface nano-crystallization by means of ultrasonic shot peening and subsequent low-temperature (523 K) aging treatment. The as-annealed coarse-grained NiTi plates were fist subjected to ultrasonic shot peening, which generates nano-grains at the surface region, and introduces dislocation networks in the interior of the NiTi sample. Both the grain boundaries and the dislocations could serve as the heterogenous nucleation sites for Ni4Ti3 nanoprecipitates during subsequent low-temperature aging treatment. Therefore, with the presence of nano-grains and dislocation networks, a homogeneous distribution of Ni4Ti3 nanoprecipitates in the sample is expected, which will strengthen largely the NiTi matrix and resist the plastic activities during the repetitive martensitic transformation. As a result, the improved stability during cyclic superelastic loading is achieved.

Sequential dual-ion irradiation is a useful technique for experimental exploration on the synergistic effects of ion accumulation and cascade damage. In this research, the helium-ion accumulation concomitant with displacement damage induced by helium and iron ions irradiation in China low active martensitic (CLAM) steel was studied by ion-irradiation, transmission electron microscopy and nano-indentation technique. The helium bubbles formed under continuous implantation of helium ions at room temperature and the helium dose forming observed bubbles resolved by TEM clearly in CLAM steel is around 0.7 × 10 17 –1.0 × 10 17 He + /cm 2 under single 100 keV He + irradiation. Significant irradiation hardening was observed in the samples with various ion- and dose-irradiations. Positive correlation between the hardening increment and the helium-ion dose has been established in single helium-ion irradiated samples. On the other hand, the subsequent Fe-ion irradiation greatly promoted the formation and growth of helium bubbles as well as dislocation loops in sequential dual-ion irradiated samples. No significant contribution of the subsequent Fe-ion irradiation on the hardness increment was found for the sequential dual-ion irradiated samples. It is suggested that the defects recombination, the combination effects of size and density of defects contribute to the degree of irradiation hardening. The calculated hardness increment based on dispersion strengthening model and the experimental microstructure analysis followed the same trend as the experimental nano-indentation data.

Accurate characterization of particulate matter (PM) exposure in young children is difficult, because personal samplers are often too heavy, bulky or impractical to be used. The Pretoddler Inhalable Particulate Environmental Robotic (PIPER) sampler was developed to help address this problem. In this study, we measured inhalable PM exposures in 2-year-olds via a lightweight personal sampler worn in a small backpack and evaluated the use of a robotic sampler with an identical sampling train for estimating PM exposure in this age group. PM mass concentrations measured by the personal sampler ranged from 100 to almost 1,200 μg/m3, with a median value of 331 μg/m3. PM concentrations measured by PIPER were considerably lower, ranging from 14 to 513 μg/m3 with a median value of 56 μg/m3. Floor cleaning habits and activity patterns of the 2-year-olds varied widely by home; vigorous play and recent floor cleaning were most associated with higher personal exposure. Our findings highlight the need for additional characterization of children’s activity patterns and their effect on personal exposures.

In this work, we show that selective laser melting (SLM), apart from producing complex structures, can also act as a metallurgical method to modify the Ni/Ti ratio of NiTi shape memory alloys, and thus providing a feasible approach to tailor the transformation temperatures and to modify the mechanical performance of NiTi alloys. NiTi samples were fabricated by SLM with a large variation of process parameters, e.g. scanning speed (v) from 400 to 1200 mm s−1, hatch spacing (h) from 40 to 110 μm, and laser power (P) from 60 to 200 W. It is found that the martensite transformation temperature changes monotonously with the respective change of v, h or P. The composition analysis suggests that the different amount of Ni-loss under various SLM process conditions is the main reason for the evolution of transformation temperatures. Most importantly, good mechanical (total elongation >10 %) and functional properties under tensile mode have been obtained despite of the large variation of SLM process parameters and the presence of extensive defects. The good tensile properties and tailorable phase transformation temperatures will provide great potential to make novel NiTi smart structures.

Autosomalplease go to the Account Update page (http://mts.hindawi.com/update/) in our Manuscript Tracking System and after you have logged in click on the ORCID link at the top of the page. This link will take you to the ORCID website where you will be able to create an account for yourself. Once you have done so, your new ORCID will be saved in our Manuscript Tracking System automatically."?> dominant polycystic kidney disease (ADPKD) is associated with a number of cellular defects such as hyperproliferation, apoptosis, and dedifferentiation. Mutations in polycystin-1 (PC1) account for ∼85% of ADPKD. Here, we showed that wild-type (WT) or mutant PC1 composed of the last five transmembrane (TM) domains and the C-terminus (termed PC1-5TMC) inhibits cell proliferation and protein translation, as well as the downstream effectors of mTOR, consistent with previous reports. Knockdown of B56α, a subunit of the protein phosphatase 2A (PP2A) complex, or application of PP2A inhibitor okadaic acid or calyculin A, abolished the inhibitory effect of PC1 and PC1-5TMC on proliferation, indicating that PP2A/B56α mediates the regulation of cell proliferation by PC1. In addition to the phosphorylated S6 and 4EBP1, B56α was also downregulated by PC1 and PC1-5TMC. Furthermore, the downregulation of B56α, which may be mediated by mTOR but not AKT, can account for the dependence of PC1-inhibited proliferation on PP2A.

Time of Flight Secondary Ion Mass Spectroscopy, X-Ray Photoelectron Spectroscopy, in situ Photo-Current Spectroscopy and electrochemical analysis were combined to characterize the physicochemical alterations induced by electrochemical passivation of the surface oxide film providing corrosion resistance to 316L stainless steel. The as-prepared surface is covered by a ~2 nm thick, mixed (Cr(III)-Fe(III)) and bi-layered hydroxylated oxide. The inner layer is highly enriched in Cr(III) and the outer layer less so. Molybdenum is concentrated, mostly as Mo(VI), in the outer layer. Nickel is only present at trace level. These inner and outer layers have band gap values of 3.0 and 2.6-2.7 eV, respectively, and the oxide film would behave as an insulator. Electrochemical passivation in sulfuric acid solution causes the preferential dissolution of Fe(III) resulting in the thickness decrease of the outer layer and its increased enrichment in Cr(III) and Mo(IV-VI). The further Cr(III) enrichment of the inner layer causes loss of photoactivity and improved corrosion protection with the anodic shift of the corrosion potential and the increase of the polarization resistance by a factor of ~4. Aging in the passive state promotes the Cr enrichment in the inner barrier layer of the passive film., Comment: 27 pages, 4 tables, 14 figures

Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in PKD1 or PKD2 which encodes polycystin-1 (PC1) and polycystin-2, respectively. PC1 was previously shown to slow cell proliferation and inhibit apoptosis but the underlying mechanisms remain elusive or controversial. Here we showed in cultured mammalian cells and Pkd1 knockout mouse kidney epithelial cells that PC1 and its truncation mutant comprising the last five transmembrane segments and the intracellular C-terminus (PC1-5TMC) down-regulate the phosphorylation of protein kinase R (PKR) and its substrate eukaryotic translation initiation factor 2 alpha (eIF2α). PKR is known to be activated by interferons and dsRNAs, inhibits protein synthesis and induces apoptosis. By co-immunoprecipitation experiments we found that PC1 truncation mutants associate with PKR, or with PKR and its activator PACT. Further experiments showed that PC1 and PC1-5TMC reduce phosphorylation of eIF2α through inhibiting PKR phosphorylation. Our TUNEL experiments using tunicamycin, an apoptosis inducer, and GADD34, an inhibitor of eIF2α phosphorylation, demonstrated that PC1-5TMC inhibits apoptosis of HEK293T cells in a PKR-eIF2α-dependent manner, with concurrent up- and down-regulation of Bcl-2 and Bax, respectively, revealed by Western blotting. Involvement of PC1-regulated eIF2α phosphorylation and a PKR-eIF2α pathway in cell apoptosis may be an important part of the mechanism underlying ADPKD pathogenesis.

With the in-depth study of the cloud, Paas platform, one of the three service of cloud computing models, is being more and more people know and attention. This paper studies the Docker lightweight containers engine technology, using the discovery, cadvisor, influxdb, sky DNS services provide basic business support of cloud computing platform, using the Core OS cluster, developed a cloud computing platform based on the Docker; Complete cloud computing platform for all services distributed configuration, deployment, monitoring; Achieved an open platform with a standard access interface specification, supports rapid installation and operation of all types of applications, provides standard application interfaces and development interface.

We computationally study the chiral transition process of the α-Ala molecule under confined different sizes of armchair SWBNNTs to explore the confinement effect. We find that the influence of a confinement environment (in armchair SWBNNTs) on the α-Ala molecule would lead to different reaction pathways. Meanwhile, the preferred reaction pathway is also different in various sizes of armchair SWBNNTs, and their energy barriers for the rate-limiting step decrease rapidly with the decreasing of the diameters of the nanotubes. It is obvious that significant decrease of the chiral transition energy barrier occurs compared with the isolated α-Ala molecule chirality conversion mechanism, by ∼15.6 kcal mol–1, highlighting the improvement in the activity the enantiomers of α-Ala molecule. We concluded that the confinement environment has a significant impact at the nanoscale on the enantiomer transformation process of the chiral molecule.

International audience; Electrochemical polarization measurements were combined with surface analysis by Time of Flight Secondary Ion Mass Spectroscopy (ToF-SIMS), X-Ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM) to study the alterations of the passive film on 316L austenitic stainless steel induced by the presence of chlorides in sulfuric acid electrolyte. The work was performed at a stage of initiation of localized corrosion preceding metastable pitting at the micrometer scale as verified by current transient analysis and AFM. The results show that Cl-ions enter the bilayer structure of the surface oxide already formed in the native oxide-covered initial surface state at concentrations below the detection limit of XPS (< 0.5 at%), mostly in the hydroxide outer layer where Fe(III) and Mo(IV,VI) species are concentrated but barely in the oxide inner layer enriched in Cr(III). Their main effect is to produce a less resistive passive state by poisoning dehydroxylation and further Cr(III) and Mo(IV,VI) enrichments obtained in the absence of chlorides. This detrimental effect can be suppressed by pre-passivation in a Cl-free electrolyte, which blocks the entry of chlorides in the passive film, including in the outer exchange layer, and enables the beneficial aging-induced variations of the composition to take place despite the presence of chlorides in the environment.

Highlights • Heart failure is increasing in prevalence associated with a huge economic burden. • ACE2 is a negative regulator of the renin–angiotensin system. • Elevated ACE2 activity is a biomarker in heart failure. • Enhancing ACE2 action may have unique therapeutic effects in patients with heart failure., Angiotensin converting enzyme 2 (ACE2), is a monocarboxypeptidase which metabolizes several peptides including the degradation of Ang II, a peptide with vasoconstrictive/proliferative/effects, to generate Ang 1–7, which acting through its receptor Mas exerts vasodilatory/anti-proliferative actions. The classical pathway of the RAS involving the ACE-Ang II-AT1 receptor axis is antagonized by the second arm constituted by the ACE2-Ang 1–7/Mas receptor axis. Loss of ACE2 enhances the adverse pathological remodeling susceptibility to pressure-overload and myocardial infarction. Human recombinant ACE2 is also a negative regulator of Ang II-induced myocardial hypertrophy, fibrosis and diastolic dysfunction and suppresses pressure-overload induced heart failure. Due to its characteristics, the ACE2-Ang 1–7/Mas axis may represent new possibilities for developing novel therapeutic strategies for the treatment of heart failure. Human recombinant ACE2 has been safely administered to healthy human volunteers intravenously resulting in sustained lowering of plasma Ang II levels. In this review, we will summarize the beneficial effects of ACE2 in heart disease and the potential use of human recombinant ACE2 as a novel therapy for heart failure.

Rationale: The classic phagocyte nicotinamide adenine dinucleotide phosphate oxidase (gp91 phox or Nox2) is expressed in the heart. Nox2 activation requires membrane translocation of the p47 phox subunit and is linked to heart failure. We hypothesized that loss of p47 phox subunit will result in decreased reactive oxygen species production and resistance to heart failure. Objective: To define the role of p47 phox in pressure overload–induced biomechanical stress. Methods and Results: Eight-week-old male p47 phox null (p47 phox knockout [KO]), Nox2 null (Nox2KO), and wild-type mice were subjected to transverse aortic constriction–induced pressure overload. Contrary to our hypothesis, p47 phox KO mice showed markedly worsened systolic dysfunction in response to pressure overload at 5 and 9 weeks after transverse aortic constriction compared with wild-type–transverse aortic constriction mice. We found that biomechanical stress upregulated N-cadherin and β-catenin in p47 phox KO hearts but disrupted the actin filament cytoskeleton and reduced phosphorylation of focal adhesion kinase. p47 phox interacts with cytosolic cortactin by coimmunoprecipitation and double immunofluorescence staining in murine and human hearts and translocated to the membrane on biomechanical stress where cortactin interacted with N-cadherin, resulting in adaptive cytoskeletal remodeling. However, p47 phox KO hearts showed impaired interaction of cortactin with N-cadherin, resulting in loss of biomechanical stress–induced actin polymerization and cytoskeletal remodeling. In contrast, Nox2 does not interact with cortactin, and Nox2-deficient hearts were protected from pressure overload–induced adverse myocardial and intracellular cytoskeletal remodeling. Conclusions: We showed a novel role of p47 phox subunit beyond and independent of nicotinamide adenine dinucleotide phosphate oxidase activity as a regulator of cortactin and adaptive cytoskeletal remodeling, leading to a paradoxically enhanced susceptibility to biomechanical stress and heart failure.

With hot construction of smart city, problem such as resources are difficult to share due to information isolated islands, repeated construction, etc. has been exposed. Based on the cloud computing and large data technology, this paper realizes the issues of accessing, processing and storage of multi-source data in urban construction as well as deep analysis and employment of data by service bus platform; also it integrates various kinds of infrastructure services to achieve one procedure from accessing to processing of multi-source data, facilitating the unified application and management, which is the trend of future development of smart city platform construction.