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Ion adsorption and hydrogen bond (HB) network reconstruction in electric double layer (EDL) have a profound impact on the interface properties. The microstructure in the bulk phase of 1.00-21.30 wt.% Na

The behaviors and kinetics of hydrogen evolution reaction (HER) on pure aluminum with passive film in the presence and absence of chloride ion are quantitatively investigated by using the tip generation/substrate collection mode of scanning electrochemical microscopy (SECM) with dual Al/Pt ultramicroelectrode (UME) as tip electrode and Pt UME as substrate electrode. The standard rate constants k0 and transfer coefficients αH of HER in ClO4−- and Cl−-containing solution are 6.9 × 10−7 cm/s and 0.22, 7.1 × 10−6 cm/s and 0.19, respectively. Results show that the kinetic of HER is slow and the destruction of Cl− on passive film can significantly promote the HER on Al surface. Moreover, these αH far less than commonly used 0.5 in corrosion research, can explain the great difference between theoretical Tafel slopes and experimental results. Besides, the existence of current plateau in Al electrode explains the large difference in corrosion potential during parallel testing.

The surface properties of weathering steel (WS) is very important for its service performance and safety, and the localized corrosion induced by inclusions is closely related to the surface properties of WS and its application. In the current work, a common spherical (Al, Mg, Ca, Mn)-oxy-sulfide inclusion was selected to investigate the corrosion evolution of complex inclusion and its effect on localized corrosion on WS surface. The results indicate the inclusion in WS consists of (Ca, Mn) sulfides part and (Ca, Al, Mg) oxides part with complex core-shell structure. Locally preferential dissolution occurs in (Ca, Mn) sulfides part as well as metal matrix around the inclusions. Furthermore, both parts of the inclusions with poor conductivity and high-density dislocation at metal matrix around the inclusions was found, which suggests that traditional micro-galvanic corrosion cell may not be the cause of inclusion-induced localized corrosion on WS surface at initial stage of corrosion. The variation in maximum and average depth around the inclusion or selected region with immersion time indicates that localized corrosion induced by inclusions is overwhelmed by uniform corrosion of WS in the latter stage of immersion, then the rust formed on WS surface consists of two layers.

Controllable rhodium(III)-catalyzed tandem [3+2] cyclization of aromatic aldehydes with maleimides is developed for the divergent synthesis of stereoselective indane-fused pyrrolidine-2,5-dione. Switchable access to different products could be achieved by employing different additives and varying the reaction time. This atom-economic transformation proceeds efficiently via the C-H bond activation directed by weakly coordinating aldehydes and is characterized by exclusive stereoselectivity, air atmosphere, and being free of nitrogen-based transient directing groups.

Carboniferous insects from China are rare. Here we report a new fossiliferous locality at the Yexi Section, western Beijing, from where Pennsylvanian insects have been discovered. These insect fossils collected from the black shales of the Benxi Formation (middle–late Moscovian to early Kasimovian) are associated with rich plant remains. The fossils are represented mainly by dictyopteran tegmina that cannot be further identified. The discovery is helpful for our understanding of the diversity and preservation of Carboniferous insects in western Beijing and also the Benxi Formation of North China.

Asteroids, as the primitive building blocks for the formation of our solar system, could reveal its evolution mechanism, and have attracted more and more attention from the public and professional institutions in recent years. Their physical properties, such as rotational period, spin axis and overall shape, can be inverted from ground- and space-based photometric observations. Since the inversion process is very time-consuming, this paper combines the genetic algorithm with the Levenberg–Marquardt (LM) algorithm, and presents a hybrid optimization algorithm based on a Cellinoid shape model for the inversion of rotational periods, which greatly improves the inversion efficiency. The proposed hybrid algorithm is applied to the synthetic lightcurves generated for an assumed Cellinoid shape model and the inverted rotational period results are consistent with the preset ones with a reduced search time, compared with the LM algorithm. Finally, multiple numerical experiments on the periods are performed on lightcurves and sparse observations of real asteroids to confirm that the proposed method can perform well in improving computational efficiency.

BackgroundStudies in recent years have shown that the neutrophil-to-lymphocyte ratio (NLR) is associated with the survival and prognosis of patients with malignant tumors.However, the utility of the NLR in predicting outcomes in patients with adenoid cystic carcinoma (ACC) of the head and neck remains unclear. Here, we examined the prognostic value of the preoperative NLR in patients with ACC of the head and neck.MethodsThis study retrospectively analyzed 71 patients with a histopathological diagnosis of ACC from August 2005 to November 2020.The optimal cutoff value was obtained by receiver operating characteristic (ROC) analysis. The characteristics of the patients were evaluated using chi-squared tests.The value of the NLR used in predicting the outcomes of these patients was analyzed using Kaplan-Meier curves and Cox regression models.ResultsThe cutoff value of the NLR was 2.071. The chi-squared tests showed that a high NLR(>2.071)was associated with tumor stage and lymph node metastasis(LNM). Kaplan-Meier survival analysis showed that the NLR>2.071 group was correlated with a shorter Overall survival(P2.071) and high age (>54 years) were independent risk factors predicting poorer outcomes in patients with ACC.ConclusionsWe suggest that the preoperative NLR is a useful biomarker for the prognosis of patients with ACC.

The aromatic aldehyde as a traceless directing group for the regionselective C-H alkylation catalyzed by rhodium(III) under aerobic atmospheric conditions has been developed. The process involves an aldehyde assisted direct addition of C-H bond to unsaturated electrophiles of acrylates or acrylic acids, and the subsequent decarbonylation. A trace amount of water is found to favor the reaction.

Cockroaches are typically recognized as an order or a suborder in insects, sometimes rank-free. Many scientific names for cockroaches are in use, most of them are ambiguous because of frequent changes of the spelling and definition, and the discrepancy between phenetics and cladistics. Omission of the authorship of the name and of the definition further confuses readers, which include taxonomists. The underlying causes of the ambiguity are the paraphyly of cockroaches and various reproduction strategies (crucial in cockroach classification) of fossil cockroaches. This paper historically reviews the scientific names for cockroaches, and recommends the following names with phylogenetic definition (details and authorship are given in the text): 1) Blattodea are cockroaches with internal ovipositors (producing oothecae of the extant type) and all descendants including termites; 2) suborder Blattaria are Blattodea minus termites; 3) order Dictyoptera are cockroaches that produce genuine oothecae and all descendants including Blattodea, Mantodea and Alienoptera; 4) Holopandictyoptera are all insects that are recognized as cockroaches and their descendants; 5) Eoblattodea are the so-called ‘roachoids’, i.e., cockroaches bearing long external ovipositors, no genuine oothecae. Accordingly, the cockroaches in the broader sense fall into three taxa: Blattaria, basal Dictyoptera, and Eoblattodea.

We report a fossil ootheca of Dictyoptera from mid-Cretaceous Burmese (Myanmar) amber. This ootheca resembles those of extant mantises, particularly Chaeteessa, and it is provisionally identified to Mantodea. Whilst Blattodea (Blattaria and Isoptera, or ‘true’ cockroaches and termites) are ruled out as the owner of this ootheca, Alienoptera and basal Dictyoptera remain possible. This is the first fossil described of the mantis-type ootheca, and also direct evidence of Dictyoptera in Cretaceous.

Triassic insect fossils from China are very limited. Here we report on numerous insect fossils discovered in the Upper Triassic Laohugou Formation at Heishanyao, Qinhuangdao, Hebei Province. These fossils are represented mainly by forewings of cockroaches and coleopteran elytra. The insect assemblage is most similar to that from the Upper Triassic Momonoki Formation of Japan. Fossils of the Laohugou Formation have been poorly known, so our discovery of new fossil insects bear significance for understanding the biota and sedimentary environment of this formation. The Mesozoic stratigraphic division in the Liujiang Basin has been controversial, and the usage of stratigraphic units has been inconsistent. Here we refine the stratigraphic sequence, from the bottom to the top, of the Upper Triassic Laohugou Formation, the Lower-Middle Jurassic Yaopo Formation, the Upper-Middle Jurassic Longmen Formation, the Upper Jurassic Tiaojishan Formation, and the Lower Cretaceous Zhangjiakou Formation. The Laohugou Formation is scattered in various basins in western Liaoning and northern Hebei, with the lower part mostly characterized by thick layers of complex conglomerates, suggesting a regional tectonic uplift. There is a sedimentary discontinuity between the Laohugou Formation and the Yaopo/Beipiao Formation, reflecting the uplifting activities during the late Late Triassic-early Early Jurassic in eastern China. The Laohugou Formation is overlaying on various ancient strata, representing the first regional unconformity of the northeastern margin of the North China Craton.

Objective To explore the repair effects of bone marrow mesenchymal stem cells (BMSCs) over-expressing miR-21 on chemotherapeutic premature ovarian failure (POF) in rats. Methods The expression vector of lentivirus-mediated miR-21 (LV-miR-21) was constructed, and BMSCs were transfected with LV-miR-21 to construct miR-21-BMSCs. A hundred rats were divided into 5 groups (20 each): normal group, model group, miR-21 group, BMSCs group and miR-21-BMSCs group. The chemotherapeutic POF model was established by intraperitoneal injection of cyclophosphamide (CTX) in rats of the latter 4 groups. Then LV-miR-21, BMSCs and miR-21-BMSCs were injected respectively into the bilateral ovaries of the rats in the latter 3 groups, and physiological saline was injected into the rats of normal group and model group. At 15, 30, 45 and 60 days after injection, the estrus cycle, estradiol (E2) and follicle stimulating hormone (FSH) level, ovarian weight, follicle count at all levels, and apoptotic rate of granulosa cells in each group were detected. Results After injection of CTX, the estrus cycle of rats remained regular in normal group, and fell into disorder in the other four groups, of which the number of rats with recovered estrus cycle in the miR-21-BMSCs group was more than the other three groups; The ovarian weight and follicle count at all levels were significantly higher in miR-21- BMSCs group than in model group, miR-21 group and BMSCs group 30, 45 and 60 days after CTX injection (P

With the combination of two evolutionary algorithms EDA and DE, a new method of initial orbit determination for satellites based on ground-based too-short-arc is established. Compared with other algorithms, the proposed method focuses on the most densely populated region in the solution space rather than the individual with best fitness value. Both the global information and local information are well fused in the search of optimum. In the method ( a , e , M ) are treated as variables of the optimization, and the optimization procedure is carried out as a two-stage hierarchical optimization problem which has three variables for each stage. Kernel density estimation is applied to build the probability distribution model without any assumptions of the specified distribution, accompanied by handling semi-major axis and eccentricity as a pair of dependent variables in the construction of the probability for the correlation between them in the practice. Numerical experiments with real ground-based observations show that the proposed method is applicable to too-short-arc with even 3 s, and the result of bias in several kilometers can be achieved with 5 ″ error added to angular measurements.

Here we describe a new corydiid cockroach, Nodosigalea burmanica gen. et sp. nov., from the middle Cretaceous Burmese amber. The well-preserved specimens exhibit a typical habitus of Corydiidae, and are characterized by nodulous pronotum, distinct wing venation and unique tarsi, the hind ones of which have different ventral structures from the fore- and midlegs. The combination of adhesive fore- and midtarsi and propulsive hindtarsi suggests a particular life style of the new genus. The phylogenetic position of the new genus within Corydiidae, however, is uncertain.

Here we describe a new praying mantis species, Burmantis hexispinea sp. nov., from middle Cretaceous Burmese amber. The new species differs from other species of Burmantis in the forefemoral spination with six large spines, instead of five. Although not the first adult of Burmantis, the holotype provides exclusive adult morphology of this genus: the wing venation is typical of Mantodea, and male terminalia are symmetrical or nearly symmetrical, with long cerci and styli. The holotype exhibits intraspecific variation in the forefemoral spination between the leg pair, and this suggests caution when proposing new taxa based on such characters.

Objective To investigate the influence of bone marrow mesenchymal stem cell (BMMSCs) overexpressing miR-21 on the apoptosis of ovarian granulosa cells (GCs). Methods The miR-21 lentiviral vector (LV-miR-21) was constructed. BMMSCs were transfected with LV-miR-21 to obtain BMMSCs stably expressing miR-21 (miR-21-BMMSCs). GCs were isolated from Wistar rats. Five groups were set up: normal group, phosphamide nitrogen mustard (PM) group, miR-21 group, BMMSCs group, and miR-21-BMMSCs group. Cells in the normal group were not treated with PM; while in PM group were added with 30μmol/L PM to induce apoptosis; for the cells in miR-21 group, apoptosis was induced by adding PM and then transfected with LV-miR-21; the cells in BMMSCs group and miR-21-BMMSCs group were treated with PM and then transfected respectively with BMMSCs and miR-21-BMMSCs at a 1:1 proportion. The apoptosis of GCs was detected with a flow cytometer 48 hours later. The mRNA expression of miR-21, phosphatase and tensin homolog deleted on chromosome Ten (PTEN) and programmed cell death factor 4 (PDCD4) was determined using qRT-PCR; the protein expression was determined using Western blotting. Results The apoptotic rate of normal group, PM group, miR-21 group, BMMSCs group and miR-21-BMMSCs group was 10.4%±1.8%, 33.4%±4.2%, 27.0%±2.5%, 28.0%±2.0% and 19.6%±1.5%, respectively; the apoptotic rate of the 5 groups differed significantly (F=59.35, P=0.00). The apoptotic rate of miR-21-BMMSCs group was lower than that of miR-21 group and BMMSCs group, but higher than that of normal group. The miR-21 expression level of miR-21-BMMSCs group (4.0310±0.2314) was upregulated significantly (F=210.062, P=0.000), and the mRNA and protein expression levels of PTEN and PDCD4 were downregulated significantly (P

The Comstock–Needham system, the foundation of main vein homology of insects, is grounded in the comparison between wing venation and wing-pad tracheation, particularly that of Plecoptera and Blattodea. However, the trachea-based approach has come into great dispute in recent years. Meanwhile, the terminology used to describe the wing venation of cockroaches requires a revision according to homology and the practical need. These motivated us to examine the wings of cockroaches, comparing the tracheation of nymphs with the tracheation and venation of adults. We find a correspondence between the tracheation and the main vein venation; therefore the trachea-based approach is effective in cockroaches. It is supported that Neopteran insects have six homologous main veins, namely, Sc, R, M, Cu, Pcu and V. We interpret the wing morphology of cockroaches in detail, including veins, furrows, folds and apical folding. RA and RP in hindwing, ScP, CuA and CuP in tegmen and hindwing, are recognized. Hindwing R + M is the only normal venal fusion in cockroaches. In addition, we propose several descriptive terms: cmv, V[1], V[s], pseudostem and characteristic posterior branch. The venation of 41 species (representing 41 genera), and the wing-pad tracheation of four of them including Diploptera punctata, which has unique apical folding, are illustrated.

Objective To investigate the therapeutic effect of heat shock preconditioned bone marrow mesenchymal stem cells (BMSCs) on chemotherapy-induced premature ovarian failure. Methods Rat's BMSCs were isolated, cultured and identified, and then treated with 42℃ water bath for 1 hour. One hundred and twenty-five female Wistar rats were randomly divided into five groups (25 each): normal control group (A group), model group (B group), sham-operation group (C group), BMSCs group (D group) and heat shock BMSCs group (E group). Chemotherapy induced-premature ovarian failure models were established with rats in all groups but A group by intraperitoneal injection of cyclophosphamide. The first day after the model established, each side ovary of rats in D group was injected with 1×106 BMSCs, in E group was injected with 1×106 heat shock pretreated BMSCs, and in C group was injected with equal amount of saline. Five rats were killed in each group at 1, 15, 30, 45 and 60 days after transplantation. The construction of ovary, amount of follicles, estrous cycle, serum estrogen, follicle-stimulating hormone (FSH) and the apoptosis of ovarian granulosa cells in each group were observed. Results The estrus cycle of rats in A group wasn't changed, while in B and C group was persistent disorder. Normal estrus cycle began to recover in some rats of E and D group 16-30 days after cell transplantation, but no statistical significance was found between the two groups (P1-15d=1.0, P16-30d=0.358, P31-45d=0.325, P46-60d=0.5). The hormone level in A group remained stable and was consistently higher than that in the other four groups (P0.05). The apoptotic index of ovarian granulosa cell declined obviously in D group and E group on day 15, 30, 45 and 60 than on day 1 after cell transplantation (P

Plants respond to diurnal and seasonal changes in temperature by reprogramming vital developmental pathways. Understanding the molecular mechanisms that define environmental modulation of plant growth and reproduction is critical in the context of climate change that threatens crop yield worldwide. Here, we report that elevated temperature accelerates fruit dehiscence in members of the Brassicaceae family including the model plant Arabidopsis thaliana and important crop species. Arabidopsis fruit development is controlled by a network of interacting regulatory genes. Among them, the INDEHISCENT (IND) gene is a key regulator of the valve-margin tissue that mediates fruit opening, hence facilitating fruit dehiscence. We demonstrated that the valve-margin development is accelerated at higher temperature and that IND is targeted for thermosensory control. Our results reveal that IND upregulation is facilitated via temperature-induced chromatin dynamics leading to accelerated valve-margin specification and dispersal of the seed. Specifically, we show that temperature-induced changes in IND expression are associated with thermosensory H2A.Z nucleosome dynamics. These findings establish a molecular framework connecting tissue identity with thermal sensing and set out directions for the production of temperature-resilient crops., Climate change is posing a global threat to crop productivity, and understanding how temperature modulates developmental outputs at the molecular level is becoming increasingly relevant to crop improvement. This study shows that fruit dehiscence (seed dispersal) is enhanced at higher temperatures across diverse species in the Brassicaceae family and reveals the thermosensory control mechanism by which this is controlled.

Introduction Xylazine, a type of α2-adrenoceptors, is a commonly used drug in veterinary medicine. Xylazine-induced changes in the content of amino acid neurotransmitters – glycine (Gly) and aspartic acid (Asp), in different brain regions and neurons were studied. Material and Methods Wistar rats were administered 50 mg/kg or 70 mg/kg of xylazine by intraperitoneal injection. In addition, in vitro experiments were conducted, in which neurons were treated with 15 μg/mL, 25 μg/mL, 35μg/mL, and 45 μg/mL of xylazine. Test methods were based on the enzyme-linked immunosorbent assays (ELISA). Results During anaesthesia, Asp levels in each brain area were significantly lower compared to the control group. Except for the cerebrum, levels of Gly in other brain areas were significantly increased during the anaesthesia period. In vitro, xylazine-related neuron secretion of Gly increased significantly compared to the control group at 60 min and 90 min. Moreover, xylazine caused a significant decrease in the levels of Asp secreted by neurons at 20 min, but gradually returned to the level of the control group. Conclusion The data showed that during anaesthesia the overall levels of Asp decreased and overall levels of Gly increased. In addition, the inhibitory effect of xylazine on Asp and the promotion of Gly were dose-dependent. Our data showed that different effects of xylazine on excitatory and inhibitory neurotransmitters provided a theoretical basis for the mechanism of xylazine activity in clinical anaesthesia.

The behaviors and kinetics of hydrogen evolution reaction (HER) on pure titanium spontaneously passivated in air (P-Ti), activated by electrochemical method (EA-Ti) and fluoride ion (FA-Ti) were investigated by impedance and scanning electrochemical microscopy (SECM). During cathodic polarization, the passive film and proton were simultaneously reduced on P-Ti, only HER current was detected on EA-Ti, while both HER and active/passive transition behavior presented on FA-Ti. Corresponding transfer coefficients and standard rate constants of HER are 0.48/6.00 × 10−12 cm/s, 0.25/7.60 × 10−7 cm/s and 0.24/1.14 × 10−6 cm/s, respectively. These differences originate from the change in electronic structure of passive film by pretreatments.

Objective To explore the therapeutic potential of miR-21 in rat model of chemotherapy-induced premature ovarian failure (POF). Methods Lentivirus-mediated miR-21 (LV-miR-21) was constructed successfully in vitro with molecular biology methods. Rats were divided into 4 groups named control group, model group, blank vector group and miR-21 group. Rat models of chemotherapy-induced POF were established in the latter 3 groups by intraperitoneal injection of cytoxan (CTX). Bilateral ovaries of rats in miR-21 group were injected with LV-miR-21, of rats in blank vector group were injected with lentivirus vector, and rats in model group received no treatment. At 1, 15, 30, 45 and 60 days after the last injection, blood sample was collected, the rats were then sacrificed and the ovaries were removed. The estrous cycle was observed by vaginal smears. The E2 level was detected by chemiluminescent immunoassay, and the follicle stimulating hormone (FSH) level was detected by homologous double antibody radiation immunoassay. Ovary weights were measured, and the follicle count was conducted through observing paraffin section under microscope. The apoptosis of ovarian granulosa cells was analyzed by TUNEL assay. Results During 15–30 days, 30–45 days and 45–60 days after the last injection, regular estrous cycle was recovered respectively in 8, 5 and 3 rats in miR-21 group. At the 15th, 30th, 45th and 60th day after the last injection, the E2 level was higher in miR-21 group than in model group and blank vector group, but the FSH level showed the opposite trend (P=0.000). At the 45th and 60th day after the last injection, the follicle numbers at all stages increased markedly in miR-21 group than in model group and blank vector group (P=0.000). At the 30th, 45th and 60th day after the last injection, the ovary weights were higher in miR-21 group than in model group and blank vector group. At the 15th, 30th, 45th and 60th day after the last injection, the apoptosis rate of ovarian granulosa cell were significantly lower in miR-21 group than in model group and blank vector group (P=0.000). Conclusion Up-regulation of miR-21 expression may partly recover the ovarian structure and function damaged by CTX. DOI: 10.11855/j.issn.0577-7402.2017.09.02

Hepatic fibrosis is a disease of the wound-healing response following chronic liver injury, and activated hepatic stellate cells (HSCs) play a crucial role in the progression of hepatic fibrosis. β-arrestin2 functions as a multiprotein scaffold to coordinate complex signal transduction networks. Although β-arrestin2 transduces diverse signals in cells, little is known about its involvement in the regulation of liver fibrosis. Our current study utilized a porcine serum-induced liver fibrosis model and found increased expression of β-arrestin2 in hepatic tissues with the progression of hepatic fibrosis, which was positively correlated with collagen levels. Furthermore, changes in human fibrotic samples were also observed. We next used β-arrestin2−/− mice to demonstrate that β-arrestin2 deficiency ameliorates CCl4-induced liver fibrosis and decreases collagen deposition. The in vitro depletion and overexpression experiments showed that decreased β-arrestin2 inhibited HSCs collagen production and elevated TβRIII expression, thus downregulating the TGF-β1 pathway components Smad2, Smad3 and Akt. These findings suggest that β-arrestin2 deficiency ameliorates liver fibrosis in mice, and β-arrestin2 may be a potential treatment target in hepatic fibrosis.