Interaction of Mechanical and Electrochemical Factors duringCorrosion Fatigue of Fe-26Cr-1Mo Stainless Steel in 1M H_2SO_4 Solution

The cyclic plastic straining electrode technique has been used to investigate the transient electrochemical behaviour of Fe-26Cr1Mo stainless steel in 1M H2SO4 solution at a passive potential.The influence of plastic strain amplitude and plastic strain rate on the dissolution current response was analysed. The experimental results showed that the transient current was dependent on the competitive process of the surface film rupture and repassivation of the new surface. The high plastic strain amplitude and the high plastic strain rate caused a change of electrochemical activity of specimen surface. In the condition of low strain amplitude and strain rate, the characteristics of current response was mainly relative tp the process of new surface repassivation.The competition kinetics has been analysed through the comparison of plastic strain rate and repassivating rate

Luminescent properties of thermally activated delayed fluorescence molecule with intramolecular π-π interaction between donor and acceptor

Influence of intramolecular π-π interaction on the luminescent properties of thermally activated delayed fluorescence（TADF） molecule（3, 5-bis（3,6-di-tert-butyl-9 H-carbazol-9-yl）-phenyl）（pyridin-4-yl） methanone（DTCBPY） is theoretically studied by using the density functional theory（DFT） and time-dependent density functional theory（TD-DFT）.Four conformations（named as A, B, C, and D） of the DTCBPY can be found by relax scanning, and the configuration C corresponds to the luminescent molecule detected experimentally. Besides, we calculate the proportion of each conformation by Boltzmann distribution, high configuration ratios（44% and 52%） can be found for C and D. Moreover, C and D are found to exist with an intramolecular π-π interaction between one donor and the acceptor; the intramolecular interaction brings a smaller Huang-Rhys factor and reduced reorganization energy. Our work presents a rational explanation for the experimental results and demonstrates the importance of the intramolecular π-π interaction to the photophysical properties of TADF molecules.

Update on enteroviral protease 2A:Structure,function,and host factor interaction

Enteroviruses(EVs)are human pathogens commonly observed in children aged 0–5 years and adults.EV infections usually cause the common cold and hand-foot-and-mouth disease;however,more severe infections can result in multiorgan complications,such as polio,aseptic meningitis,and myocarditis.The molecular mechanisms by which enteroviruses cause these diseases are still poorly understood,but accumulating evidence points to two enterovirus proteases,2Apro and 3Cpro,as the key players in pathogenesis.The 2Apro performs post-translational proteolytic processing of viral polyproteins and cleaves several host factors to evade antiviral immune responses and promote viral replication.It was also discovered that coxsackievirus-induced cardiomyopathy was caused by 2Apro-mediated cleavage of dystrophin in cardiomyocytes,indicating that cellular protein proteolysis may play a key role in enterovirus-associated diseases.Therefore,studies of 2Apro could reveal additional substrates that may be associated with specific diseases.Here,we discuss the genetic and structural properties of 2Apro and review how the protease antagonizes innate immune responses to promote viral replication,as well as novel substrates and mechanisms for 2Apro.We also summarize the current approaches for identifying the substrates of 2Apro to discover novel mechanisms relating to certain diseases.

THE APPROXIMATE SOLUTION OF PENNY-SHAPED CRACKS PERIODICALLY DISTRIBUTED IN INFINITE ELASTIC BODY

The penny-shaped cracks periodically distributed in infinite elastic body are studied. The prob- lem is approximately simplified to that of a single crack embedded in finite length cylinder and the stress intensity factor is obtained by solving a Fredholm integral equation. Numerical results are given and the effects of crack interaction on the stress intensity factor are discussed.

Interaction among controlling factors for landslides triggered by the 2008 Wenchuan, China Mw 7.9 earthquake

The 12 May 2008 Mw 7.9 Wenchuan, China earthquake triggered about 200,000 landslides, which were controlled by a number of factors. This study examines five factors： slope angle, slope aspect, lithology, peak ground acceleration （PGA）, and fault side （relative position on the seismogenic fault, i.e., hanging wall or footwall）, to determine how these factors control the co-seismic land- slide occurrence and whether one or more factors, acting alone or in concert, are involved in promoting or suppressing landslides. We performed a multi-factor statistical analysis using data from the 2008 Wenchuan earthquake. The results show that in the areas characterized by steep topography or where strong ground shaking occurred during the earthquake, there is a closer relation- ship between slope aspect and landslide number density （LND） than other areas. The relationship between lithology and LND values depends on PGA. In turn, the relationship between LND values and PGA is also influenced by lithology. In addition, the controlling effect of lithology on co-seismic landslides on the hanging wall of the seismogenic fault is greater than that on the footwall. Examining interactions among these factors can improve understanding of the mechanisms of co-seismic landslide occurrence.

Control of flowering and inflorescence architecture in tomato bysynergistic interactions between ALOG transcription factors

Inflorescences are flower-bearing shoots that originate from pools of stem cells in shoot apical meristems (SAM).Inflorescence architecture is determined by a process of meristem maturation,during which stem cell fate switches from a vegetative to a reproductive growth program.A major factor in plant reproductive success in nature and yield in agriculture is the number of branches and flowers on inflorescences (Kobayashi and Weigel,2007;

Panel data models with cross-sectional dependence: a selective review

In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues of cross-sectional dependence, and introduces the concepts of weak and strong cross-sectional dependence. Then, the main attention is primarily paid to spatial and factor approaches for modeling cross-sectional dependence for both linear and nonlinear （nonparametric and semiparametric） panel data models. Finally, we conclude with some speculations on future research directions.

SOME HUMORAL FACTORS AND THEIR INTERACTION ON ACUTE HYPOXIC PULMONARY PRESSOR RESPONSE

To determine the effect of humoral factors and their interaction on the developement of acute hypoxic pulmonary pressor response (HPPR), we performed studies in 16 mongrel dogs. We measured plasma levels of noradrealin (NE), angiotensin Ⅱ (AII), prostaglandin F2α (PGF2α), 6-keto-prostaglandin F1α (6KPGF1α), thromboxane B2 (TXB2), leukotriene B4 (LTB4) and 5-hydroxytryptamine (5-HT) before, during and after HPPR. Multiple regression analysis showed that the changes of pulmonary arterial systolic pressure (PASP) and pulmonary arterial diastolic pressure (PADP) correlated well with those of plasma concentration of NE, PGF2α and 6KPGF1α, respectively (r were equal to 0.633 and 0.668, respectively, P<0.01). The results of orthogonal experiment analysis with an injection of exogenous NE, PGF2α and PGIα into main pulmonary artery of dogs showed that NE and the interaction of PGF2α and PGI2α increased PASP (P<0.05) and PGI2 attenuated PASP (P<0.01). The interaction of PGF2α and PGI2 and of PGF2α and NE increased PADP(P<0.01) and PGI2 attenuated PADP (P<0.01).

Analysis on Local and Concurrent Commutation Failure of Multi-infeed HVDC Considering Inter-converter Interaction

This paper provides a comprehensive analysis of local and concurrent commutation failure(CF)of multi-infeed high-voltage direct current(HVDC)system considering multi-infeed interaction factor(MIIF).The literature indicates that the local CF is not influenced by MIIF,whereas this paper concludes that both the local CF and concurrent CF are influenced by MIIF.The ability of remote converter to work under reduced reactive power enables its feature to support local converter via inter-connection link.The MIIF measures the strength of electrical connectivity between converters.Higher MIIF gives a clearer path to remote converter to support local converter,but at the same time,it provides an easy path to local converter to disturb remote converter under local fault.The presence of nearby converter increases the local commutation failure immunity index(CFII)while reducing concurrent CFII.Higher MIIF causes reactive power support to flow from remote converter to local converter,which reduces the chances of CF.A mathematical approximation to calculate the increase in local CFII for multi-infeed HVDC configurations is also proposed.A power flow approach is used to model the relation between MIIF and reactive power support from remote end.The local and concurrent CFIIs are found to be inverse to each other over MIIF;therefore,it is recommended that there is an optimal value of MIIF for all converters in close electric proximity to maintain CFII at a certain level.The numerical results of established model are compared with PSCAD/EMTDC simulations.The simulation results show the details of the influence of MIIF on local CF and concurrent CF of multi-infeed HVDC,which validates the analysis presented.

Interacting Stress Intensity Factors of Multiple Elliptical-Holes and Cracks Under Far-Field and Arbitrary Surface Stresses

Calculating interacting stress intensity factors(SIFs)of multiple ellipticalholes and cracks is very important for safety assessment,stop-hole optimization design and resource exploitation production in underground rock engineering,e.g.,buried tunnels,deep mining,geothermal and shale oil/gas exploitation by hydraulic fracturing technology,where both geo-stresses and surface stresses are applied on buried tunnels,horizontal wells and natural cracks.However,current literatures are focused mainly on study of interacting SIFs of multiple elliptical-holes(or circularholes)and cracks only under far-field stresses without consideration of arbitrary surface stresses.Recently,our group has proposed a new integral method to calculate interacting SIFs of multiple circular-holes and cracks subjected to far-filed and surface stresses.This new method will be developed to study the problem of multiple elliptical-hole and cracks subjected to both far-field and surface stresses.In this study,based on Cauchy integral theorem,the exact fundamental stress solutions of single elliptical-hole under arbitrarily concentrated surface normal and shear forces are derived to establish new integral equation formulations for calculating interacting SIFs of multiple elliptical-holes and cracks under both far-field and arbitrary surface stresses.The new method is proved to be valid by comparing our results of interacting SIFs with those obtained by Green’s function method,displacement discontinuity method,singular integral equation method,pseudo-dislocations method and finite element method.Computational examples of one elliptical-hole and one crack in an infinite elastic body are given to analyze influence of loads and geometries on interacting SIFs.Research results show that whenσ_(xx)^(∞)≥σ^(yy′)^(∞),there appears a neutral crack orientation angle b0(without elliptical-hole’s effect).Increasing s¥xx/s¥yy and b/a(close to circularhole)usually decreases b0 of KI and benefits to the layout of stop-holes.The surface compressive stresses applied onto elliptical-hole(n)and crack(p)have significant influence on interacting SIFs but almost no on b0.Increasing n and p usually results in increase of interacting SIFs and facilitates crack propagation and fracture networks.The elliptical-hole orientation angle(a)and holed-cracked distance(t)have great influence on the interacting SIFs while have little effect on b0.The present method is not only simple(without any singular parts),high-accurate(due to exact fundamental stress solutions)and wider applicable(under far-field stresses and arbitrarily distributed surface stress)than the common methods,but also has the potential for the anisotropic problem involving multiple holes and cracks.

PCH1 and PCHL Directly Interact with PIF1,Promote Its Degradation,and Inhibit Its Transcriptional Function during Photomorphogenesis

PHOTOPERIODIC CONTROL OF HYPOCOTYL 1(PCH1)and PCH1-LIKE(PCHL)were shown to directly bind to phytochrome B(phyB)and suppress phyB thermal reversion,resulting in plants with dramatically enhanced light sensitivity.Here,we show that PCH1 and PCHL also positively regulate various light responses,including seed germination,hypocotyl gravitropism,and chlorophyll biosynthesis,by physically interacting with PHYTOCHROME INTERACTING FACTOR 1(PIF1)and CONSTITUTIVE PHOTOMORPHO-GENIC 1(COP1).PCH1 and PCHL interact with PIF1 both in the dark and light,and regulate PIF1 abundance.Moreover,PCH1 and PCHL facilitate the physical interaction between phyB and PIF1 in vivo to promote the light-induced degradation of PIF1.PCH1 and PCHL also inhibit the DNA-binding ability of PIF1 to negatively regulate the expressions of PIF1 target genes.In addition,PCH1 and PCHL interact with COP1 and undergo degradation through the 26S proteasome pathway in the dark.Consistently,pch1 suppresses cop1 phenotype in darkness.Collectively,our study reveals a novel mechanism by which PCH1 and PCHL regulate diverse light responses not only by stabilizing phyB Pfrform but also by directly interacting with PIF1 and COP1,providing a molecular understanding of the control of hypocotyl growth by these proteins.

Crystal-field analyses for trivalent lanthanide ions in LiYF_4

Based on the completely parametric crystal-field model, the energy level parameters, including free-ion parameters and crystal-field parameters, obtained by fitting the experimental energy level data sets of Ln^（3＋） in LiYF_4 were systematically analyzed. The results revealed that the regular variation trends of the major parameters at relatively low site symmetry still existed. The g factors of ground states were calculated using the parameters obtained from least-squares fitting. The results for Ce^（3＋）, Nd^（3＋）, Sm^（3＋）, Dy^（3＋） and Yb^（3＋） were in good agreement with experiment, while those of Er^（3＋） deviated from experiment dramatically. Further study showed that the g factors depended strongly on B_4~6, and a slightly different B_4~6 value of -580cm^（-1） led to g factors agreeing well with the experimental values.