Abstract
Strong electric fields can accelerate molecular dissociation reactions. The phenomenon known as the Wien effect was previously observed using high-voltage electrolysis cells that produced ...fields of about 10
7
V m
−1
, sufficient to accelerate the dissociation of weakly bound molecules (e.g., organics and weak electrolytes). The observation of the Wien effect for the common case of water dissociation (H
2
O
$$\leftrightarrows$$
⇆
H
+
+ OH
−
) has remained elusive. Here we study the dissociation of interfacial water adjacent to proton-permeable graphene electrodes and observe strong acceleration of the reaction in fields reaching above 10
8
V m
−1
. The use of graphene electrodes allows measuring the proton currents arising exclusively from the dissociation of interfacial water, while the electric field driving the reaction is monitored through the carrier density induced in graphene by the same field. The observed exponential increase in proton currents is in quantitative agreement with Onsager’s theory. Our results also demonstrate that graphene electrodes can be valuable for the investigation of various interfacial phenomena involving proton transport.
Abstract
Recent experiments demonstrated that proton transport through graphene electrodes can be accelerated by over an order of magnitude with low intensity illumination. Here we show that this ...photo-effect can be suppressed for a tuneable fraction of the infra-red spectrum by applying a voltage bias. Using photocurrent measurements and Raman spectroscopy, we show that such fraction can be selected by tuning the Fermi energy of electrons in graphene with a bias, a phenomenon controlled by Pauli blocking of photo-excited electrons. These findings demonstrate a dependence between graphene’s electronic and proton transport properties and provide fundamental insights into molecularly thin electrode-electrolyte interfaces and their interaction with light.
Mechanical behaviors of transformation induced plasticity (TRIP) steels largely depend on the amount and stability of austenite. In this investigation, a large volume fraction of austenite (>65%) was ...produced in a hot-rolled Fe-11Mn-3.8Al-0.18C TRIP steel by solution treatment in the temperature range of 750–800°C for 1h. The hot-rolled alloy exhibited an excellent combination of total elongation of 35–40% and ultimate tensile strength of 880–1100MPa and this was found to have a similar or higher level of tensile properties compared with other TRIP steels. In the meantime, less cold-rolling work or annealing time was required in the present work. The outstanding properties of the experimental steel were mainly attributed to the enhanced TRIP effect due to the large fraction of austenite. It is shown that the morphology played a more significant role than orientation in the stability of austenite.
MYC activation at modest levels has been frequently found in hepatocellular carcinoma. However, its significance in hepatocarcinogenesis has remained obscure. Here we examined the role of Myc ...activation in mouse liver tumours induced by hepatocytic expression of myristoylated AKT (AKT) and/or mutant HRAS
(HRAS) via transposon-mediated gene integration. AKT or HRAS alone required 5 months to induce liver tumours, whereas their combination generated hepatocellular carcinoma within 8 weeks. Co-introduction of AKT and HRAS induced lipid-laden preneoplastic cells that grew into nodules composed of tumour cells with or without intracytoplasmic lipid, with the latter being more proliferative and associated with spontaneous Myc expression. AKT/HRAS-induced tumorigenesis was almost completely abolished when MadMyc, a competitive Myc inhibitor, was expressed simultaneously. The Tet-On induction of MadMyc in preneoplastic cells significantly inhibited the progression of AKT/HRAS-induced tumours; its induction in transformed cells suppressed their proliferative activity with alterations in lipid metabolism and protein translation. Transposon-mediated Myc overexpression facilitated tumorigenesis by AKT or HRAS, and when it was co-introduced with AKT and HRAS, diffusely infiltrating tumours without lipid accumulation developed as early as 2 weeks. Examination of the dose-responses of Myc in the enhancement of AKT/HRAS-induced tumorigenesis revealed that a reduction to one-third retained enhancing effect but three-times greater introduction damped the process with increased apoptosis. Myc overexpression suppressed the mRNA expression of proteins involved in the synthesis of fatty acids, and when combined with HRAS introduction, it also suppressed the mRNA expression of proteins involved in their degradation. Finally, the MYC-positive human hepatocellular carcinoma was characterized by the cytoplasm devoid of lipid accumulation, prominent nucleoli and a higher proliferative activity. Our results demonstrate that in hepatocarcinogenesis induced by both activated AKT and HRAS, activation of endogenous Myc is an enhancing factor and adequate levels of Myc deregulation further facilitate the process with alterations in cellular metabolism.
Background and Aims
Phenotypic traits of grape bunches are known to be related with grapevine yield, wine flavour and sensitivity to disease. Aiming to solve a phenotypic bottleneck in current ...breeding studies as well as to improve the performance of phenotypic tools, we put forward a combination of grammar‐based reconstruction and vision‐based reconstruction, and propose an empirical reconstruction grammar restricted by an outline hull, which can model parameters of the entire bunch framework.
Methods and Results
Statistical analysis of manual measurements of bunches was undertaken to empirically build a reconstruction grammar for a specific grape cultivar. During the reconstruction procedure, the grammar takes account of the estimation of the topological architecture and the geometrical parameters of bunch elements, while the outline hull formed from the input two‐dimensional (2D) image is used to constrain the volume and the overall shape of the bunch model. The reconstruction results indicated that the average percentage error of quantity estimation for various internode types ranged from 19.1 to 41.1%, and the average percentage error for individual lengths of respective internode types ranged from −0.4 to 10.4%.
Conclusions
The proposed three‐dimensional grape bunch reconstruction method achieves the parameter modelling of bunch components by using 2D images as input, and the performance has been shown to be an improvement over existing work.
Significance of the Study
The proposed method enables a more accurate reconstruction of grape bunch framework, which facilitates the automatic extraction of phenotypic traits and the improvement of breeding programs along with vineyard management. Due to its simple sensor input requirements, it is able to be applied under field conditions.
The microstructures were observed in C-Mn steel and statistical analysis of the inclusions produced when trace amounts of rare earth were added to the steel. The results show that the content of ...intragranular acicular ferrite decreased in the order of being treated with La+Ce/La/Ce in C-Mn steel after the treatment of different kinds of rare earths. The optimum mass ratio of La and Ce for La+Ce combined treatment is 3:1.The best incubation time after Le+Ce (3:1) treatment is 5 min. The size of inclusion nuclei favouring intragranular acicular ferrite nucleation concentrates in the range of 1-4 μm. The disregistries between rare earth inclusions and α-Fe are small, which plays an important role in rare earth inclusions inducing intragranular acicular ferrite nucleation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Background: Apixaban is an oral, direct and highly selective factor Xa (FXa) inhibitor in late‐stage clinical development for the prevention and treatment of thromboembolic diseases. Objective: We ...evaluated the in vitro properties of apixaban and its in vivo activities in rabbit models of thrombosis and hemostasis. Methods: Studies were conducted in arteriovenous‐shunt thrombosis (AVST), venous thrombosis (VT), electrically mediated carotid arterial thrombosis (ECAT) and cuticle bleeding time (BT) models. Results: In vitro, apixaban is potent and selective, with a Ki of 0.08 nm for human FXa. It exhibited species difference in FXa inhibition FXa Ki (nm): 0.16, rabbit; 1.3, rat; 1.7, dog and anticoagulation EC2× (μm, concentration required to double the prothrombin time): 3.6, human; 2.3, rabbit; 7.9, rat; 6.7, dog. Apixaban at 10 μm did not alter human and rabbit platelet aggregation to ADP, γ‐thrombin, and collagen. In vivo, the values for antithrombotic ED50 (dose that reduced thrombus weight or increased blood flow by 50% of the control) in AVST, VT and ECAT and the values for BT ED3× (dose that increased BT by 3‐fold) were 0.27 ± 0.03, 0.11 ± 0.03, 0.07 ± 0.02 and > 3 mg kg−1 h−1 i.v. for apixaban, 0.05 ± 0.01, 0.05 ± 0.01, 0.27 ± 0.08 and > 3 mg kg−1 h−1 i.v. for the indirect FXa inhibitor fondaparinux, and 0.53 ± 0.04, 0.27 ± 0.01, 0.08 ± 0.01 and 0.70 ± 0.07 mg kg−1 day−1 p.o. for the oral anticoagulant warfarin, respectively. Conclusions: In summary, apixaban was effective in the prevention of experimental thrombosis at doses that preserve hemostasis in rabbits.
RNAi‐based therapy is a promising strategy for the prevention of ischemia‐reperfusion injury (IRI). However, systemic administration of small interfering RNA (siRNA) may cause globally nonspecific ...targeting of all tissues, which impedes clinical use. Here we report a hepatocyte‐specific delivery system for the treatment of liver IRI, using galactose‐conjugated liposome nanoparticles (Gal‐LipoNP). Heptocyte‐specific targeting was validated by selective in vivo delivery as observed by increased Gal‐LipoNP accumulation and gene silencing in the liver. Gal‐LipoNP TLR4 siRNA treatment resulted in a significant decrease of serum alanine transferase (ALT) and aspartate transaminase (AST) in a hepatic IRI model. Histopathology displayed an overall reduction of the injury area in the Gal‐LipoNP TLR4 siRNA treated mice. Additionally, neutrophil accumulation and lipid peroxidase‐mediated tissue injury, detected by MPO, MDA and ROS respectively, were attenuated after Gal‐LipoNP TLR4 siRNA treatment. Moreover, therapeutic effects of Gal‐LipoNP TLR4 siRNA were associated with suppression of the inflammatory cytokines IL‐1 and TNF‐α. Taken together, this study is the first demonstration of liver IRI treatment using liver‐specific siRNA delivery.
Pretreatment with Toll‐like Receptor 4 siRNA delivered by targeted liposomal nanoparticles can prevent experimental liver ischemia reperfusion injury.
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