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• An isogeometric method for buckling analysis of composite cylindrical shells under external pressure is proposed. • Based on Reissner–Mindlin shell theory, effects of large deformation is considered in this method, and a modified arc-length method is proposed to track the equilibrium path after limit points. • Post-buckling analysis of different composite pressure shell models are computed and verified, both snap-instability behavior and bifurcation behavior are observed. • For linear buckling analysis of variable stiffness composite shell cases, the efficiency of the proposed method is confirmed for achieving same precision as FEM with fewer elements. Composite cylindrical pressure hulls are thin-walled structures widely used for autonomous underwater vehicles. Buckling failure is one of the most important failure modes for these shells under external pressure. In existing buckling studies of cylindrical pressure hulls, FEM is the most popular analysis method but not efficient enough when dealing with structures with complex material distributions such as the variable stiffness composite shells. Motivated by this, an isogeometric method for buckling prediction and post-buckling analysis of variable stiffness composite underwater pressure shell is proposed in this article. In this method, based on Reissner–Mindlin shell formulas undergoing large deformation, a buckling analysis framework in IGA forms is established. Then a modified arc-length method is proposed based on kinematics used in the shell formulas, and is used to overcome the inaccuracy caused by the 2 degrees of freedom node rotation in the prediction step of arc-length method. In addition, the influence of bifurcation is considered, which may seriously affect the precision of buckling behavior simulation when the limit point is close to a bifurcation point. The computational accuracy of this framework has been validated in a series of constant stiffness composite shell cases involving buckling load prediction and post-buckling behavior simulation. For variable stiffness composite hull cases, this framework achieves the same precision as FEM with fewer elements. Therefore, the proposed framework provides an efficient way for the buckling design of underwater variable stiffness composite pressure hulls. [ABSTRACT FROM AUTHOR]

In this paper, a semi-analytical approach is proposed to investigate the dynamic buckling behavior of functionally graded carbon nanotubes reinforced composite (FG-CNTRC) cylindrical shell under dynamic displacement load. Five types of carbon nanotubes (CNTs) distribution are considered, in which the uncertainty of CNTs distribution is also taken into account. Combining with the first-order shear deformation theory and von-Kármán strains, the nonlinear governing equations for dynamic buckling analysis of FG-CNTRC cylindrical shell considering the thermal effects are derived. Then, Galerkin method and the fourth-order Runge-Kutta method are employed to solve the governing equations. And the dynamic critical buckling condition of FG-CNTRC cylindrical shell is determined by the Budiansky-Roth criterion. Compared with the published literatures, the feasibility and accuracy of proposed analysis approach are validated. Finally, the parametric studies are systematically carried out to analyze the effects of CNTs distribution type, CNTs volume fractions, the uncertainty of CNTs distribution, the loading rate and form of dynamic displacement load, structural characteristics and temperature on the dynamic buckling behavior of FG-CNTRC cylindrical shell. [ABSTRACT FROM AUTHOR]

Abstract Thin-walled cylindrical shells subjected to axial load are prone to buckling and very sensitive to the geometric imperfections. In order to determine a rational design load for axially loaded cylindrical shells, different analytical and numerical design methods have been developed. As an extension of single perturbation load approach (SPLA), multiple perturbation load approach (MPLA) is a promising method but has not been thoroughly studied. In this paper, the buckling tests of three steel cylindrical shell specimens are conducted. Combined with experimental and numerical results, the advantages and limitations of several commonly used design methods are discussed in detail, including NASA SP-8007, the measured imperfection approach, SPLA and MPLA. The results validate that SPLA is indeed risky to be adopted as a design method for isotropic metallic cylindrical shells. Meanwhile, it indicates that MPLA can not only improve the knock-down factor but also give a more safe design load than SPLA. The comprehensive numerical investigations are performed to study the effects of each perturbation load parameter on MPLA, including the number of perturbation loads, their relative position and magnitude. It is found that the symmetry of perturbation loads plays an important role in the global buckling load of cylindrical shell. Moreover, some guidance for the future application of MPLA is provided and the four perturbation load approach (4PLA) is proposed as an improved method for the preliminary design of isotropic metallic cylindrical shells. Highlights • The applicability of MPLA in the design of steel cylindrical shell is validated by buckling tests. • Compared with SPLA, MPLA is a more rational and safe design method for isotropic metallic cylindrical shells. • The symmetry of perturbation loads plays an important role in the global buckling load. • 4PLA is proposed as an improved design method for metallic cylindrical shells. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2 ) is one of the most important solid lubricants used in titanium (Ti) to reduce the friction coefficient. The adherent capability between MoS 2 and Ti determines its application. A layer of titanium dioxide nanotube (TNT) array film had been prepared to strengthen the binding force between the solid lubricant and Ti substrate. The existence of the TNT increases the strength of the basement and provide a solid support for MoS 2 nanosheets. The tribology test reveals that the new structure of Ti/TNT/MoS 2 exhibits extremely stable performance. Dramatic improvement in combining capability (471 × ) at low friction coefficient (0.11) was realized compared with Ti/MoS 2 structure, suggesting the promising application in friction and wear field, for example, Ti fasteners used in aerospace. [ABSTRACT FROM AUTHOR]

Although deep neural networks (DNNs) are being a revolutionary power to open up the AI era, the notoriously huge hardware overhead has challenged their applications. Recently, several binary and ternary networks, in which the costly multiply-accumulate operations can be replaced by accumulations or even binary logic operations, make the on-chip training of DNNs quite promising. Therefore there is a pressing need to build an architecture that could subsume these networks under a unified framework that achieves both higher performance and less overhead. To this end, two fundamental issues are yet to be addressed. The first one is how to implement the back propagation when neuronal activations are discrete. The second one is how to remove the full-precision hidden weights in the training phase to break the bottlenecks of memory/computation consumption. To address the first issue, we present a multi-step neuronal activation discretization method and a derivative approximation technique that enable the implementing the back propagation algorithm on discrete DNNs. While for the second issue, we propose a discrete state transition (DST) methodology to constrain the weights in a discrete space without saving the hidden weights. Through this way, we build a unified framework that subsumes the binary or ternary networks as its special cases, and under which a heuristic algorithm is provided at the website https://github.com/AcrossV/Gated-XNOR . More particularly, we find that when both the weights and activations become ternary values, the DNNs can be reduced to sparse binary networks, termed as gated XNOR networks (GXNOR-Nets) since only the event of non-zero weight and non-zero activation enables the control gate to start the XNOR logic operations in the original binary networks. This promises the event-driven hardware design for efficient mobile intelligence. We achieve advanced performance compared with state-of-the-art algorithms. Furthermore, the computational sparsity and the number of states in the discrete space can be flexibly modified to make it suitable for various hardware platforms. [ABSTRACT FROM AUTHOR]

In practical engineering, cutouts in thin-walled cylindrical shells are usually welded with ringed stiffeners for the purpose of connect and seal. In this paper, experimental and numerical studies have been conducted to investigate the effects of ringed stiffener on the buckling behavior of perforated cylindrical shells under axial compression. Three test specimens with ringed stiffener and three specimens without ringed stiffener are manufactured and tested. The mid-surface imperfections of all specimens are measured and introduced into the finite element model. The finite element method using static analysis with artificial damping is used to simulate the displacement controlled compression tests. Good agreement is found between the numerical and experimental results. It is found that the global buckling loads of perforated shells are improved by ringed stiffener. The larger the cutout size is, the more obvious improvement shows. In addition, effects of ringed stiffener on axial stiffness and imperfection sensitivity of perforated shells are studied in details. The relationship between ringed stiffener thickness and global buckling load of perforated shell is also discussed. Meanwhile, a critical thickness parameter k of approximately 15% is proposed. [ABSTRACT FROM AUTHOR]

Thin-walled cylindrical shell is a fundamental engineering structure which has efficient load-carrying capacity. In practical application, this structure is more easily subjected to localized axial compression loads and is prone to buckling. However, until now there is only limited studies on the buckling problems of multi-region localized axial compression loaded cylindrical shells. To elucidate the buckling behaviors of cylindrical shell under such kind of non-uniform loading condition, experimental and numerical studies are carried out in this paper. Twenty cylindrical shell test specimens with different types of localized axial compression loads are fabricated and tested. The corresponding finite element model considering the measured initial geometric imperfections is established for buckling analysis, and good agreement between the numerical and experimental results is validated. Then the buckling failure mode and axial load-carrying capacity of cylindrical shells are investigated in details. Finally, the imperfection sensitivity of thin-walled cylindrical shell under multi-region localized axial compression is discussed. It is found that the number of loading regions and the total loading area have significant effects on buckling failure mode and axial load-carrying capacity of cylindrical shells. The results obtained from experimental and numerical studies can provide some important guidance or suggestions for the design of thin-walled cylindrical shell structures in actual engineering. • Buckling tests of 20 metallic thin-walled cylindrical shell specimens under multi-region localized axial compression loads were performed. • Finite element model for studying buckling behaviors of cylindrical shell were established. • Buckling failure mode and axial load-carrying capacity of cylindrical shell were systematically investigated for the first time. • Imperfection sensitivity of cylindrical shell under multi-region localized axial compression loads was discussed. [ABSTRACT FROM AUTHOR]

• The feasibility evaluation of Bacillus coagulans as an alternative to antibiotics. • Bacillus coagulans can improve the growth performance of weaning piglets. • Bacillus coagulans can improve the Diarrhoea of weaning piglets. • Bacillus coagulans is beneficial for the intestinal health of weaned piglets. • Bacillus coagulans can be used as an alternative microecological additive. The performance of weaned piglets suffers from severe limitations resulting from diarrhoea. Therefore, this trial was performed to investigate the effects of Bacillus coagulans as an alternative to antibiotics on piglet growth performance and intestinal health. Ninety (initial BW = 7.70 ± 0.17 kg, weaning age of 26 days) healthy weaned piglets with similar BWs were selected and randomised into three treatment groups. Pigs in the negative control (NC) group were fed a basal diet, pigs in the positive control (PC) group were fed the basal diet plus antibiotics, and pigs in the test group (BC) were fed the basal diet plus Bacillus coagulans at 600 g/t; the trial lasted for 28 days. The results showed that the ratios of feed to gain (F:G) of both the BC and PC groups from 1 to 21 days were significantly lower (P < 0.05), and the average daily weight gain (ADG) of the BC group from 22 to 28 days was significantly higher (P < 0.05) than that of the NC group in terms of growth performance. The diarrhoea index was lowest in the PC group, followed by the BC group, and highest in the NC group. The BC group had a lower diarrhoea index at the later stage. We performed 16S rRNA sequencing to measure the intestinal bacteria and found that the BC group had a higher intestinal bacteria diversity than the NC and PC groups (P < 0.05). From days 1 to 21, the main differential species were Ruminococcaceae _UCG-014 and Faecalibacterium (P < 0.05); from days 22 to 28, the main differential species were Prevotella_9, unclassified_f__ Lachnospiraceae , Anaerovibrio , and Ruminococcaceae _UCG-002 (P < 0.05). The correlation analysis between growth performance and species revealed specific gut microorganisms responsible for variation in F:G, ADG, and diarrhoea index, such as Prevotellaceae , Clostridium _sensu_stricto_1, Ruminococcaceae , Phascolarctobacterium , and Anaerovibrio. In conclusion, Bacillus coagulans changed the microbial composition in the faeces of weaned piglets, which had positive effects on growth performance and the diarrhoea index. Therefore, our study provided new insight into the future application of Bacillus coagulans as an additive. [ABSTRACT FROM AUTHOR]

• Sub-Cellular Localization results showed that ATHB-6 fusion proteins were only localized in the nucleus. • The malondialdehyde content was lower than the wild type under drought tolerance, proving that the introduction of the ATHB-6 gene can improve the drought tolerance of plants. • Follow-up analysis showed that ATHB-6 could promote root growth and activities of a series of ROS-scavenging enzymes in maize. • Moreover, overexpression of ATHB-6 in maize activated the expression of critical genes in the ROS signals pathway and ABA-dependent pathway under drought tolerance. • Our results provides a significant advancement in undestanding the functions of HD-Zip transcription factors in maize. Homeo-Leucine Zipper (HD-Zip) proteins are a class of transcription factors unique to higher plants and are involved in plant stress responses and regulation of growth and development. However, the function of maize HD-Zip genes in enhancing drought tolerance is unknown. Here, Sub-Cellular Localization results showed that ATHB-6 fusion proteins were only localized in the nucleus. The malondialdehyde content was lower than the wild type under drought tolerance, proving that the introduction of the ATHB-6 gene can improve the drought tolerance of plants. Follow-up analysis showed that ATHB-6 could promote root growth and activities of a series of ROS-scavenging enzymes in maize. Moreover, overexpression of ATHB-6 in maize activated the expression of critical genes in the ROS signals pathway and ABA-dependent pathway under drought tolerance.Our results provides a significant advancement in undestanding the functions of HD-Zip transcription factors in maize. [ABSTRACT FROM AUTHOR]

Abstract: The structural, electronic and magnetic properties of Sr1− x Na x RuO3 have been investigated using the pseudo-potential plane wave method within the generalized gradient approximation GGA+ U method by first principles. The results show that all structures of Sr1– x Na x RuO3 (x =0, 0.125, 0.25) are ferromagnetic phase. There is a more strong Jahn–Teller distortion of the RuO6 octahedra in Na doped compounds. Na doping cannot induce magnetic phase transition in SrRuO3. A Stoner mechanism for ferromagnetism in SrRuO3 is weakened by Na doping, which can lead to a reduction of effective magnetic moment. Na doping lowers the density of states at Fermi lever and decreases the number of electrons above the Fermi energy, which indicates that the pure SrRuO3 is more metallic than Sr0.875Na0.125RuO3 and Sr0.75Na0.25RuO3. However, the metal-insulator transition has not happened when Na only substitutes on the Sr site in SrRuO3. [Copyright &y& Elsevier]

Abstract: The acceleration of urbanization and global worming are making urban rain-flood disaster more ordinary and more serious recently. Summing up the characters of urban rain-floods, the mechanism of urban rain-flood disasters is analyzed. More ever, the main countermeasures to prevent urban rain-flood disasters are stated. Finally, the optimal method to utilize urban rain-flood comprehensively is put forward. [Copyright &y& Elsevier]

Abstract: The acceleration of urbanization and global worming are making urban rain-flood disaster more ordinary and more serious recently. Summing up the characters of urban rain-floods, the mechanism of urban rain-flood disasters is analyzed. More ever, the main countermeasures to prevent urban rain-flood disasters are stated. Finally, the expert system for urban rain-flood utilization is put forward. [Copyright &y& Elsevier]

In the second part of this series paper, a high-fidelity finite element model was established first to systematically study the buckling behaviors of thin-walled cylindrical shell subjected to localized axial compression load. By comparing with the experimental results, the feasibility and accuracy of the present FE model were validated. Then, the buckling mechanism, failure mode and load carrying capacity of cylindrical shell under localized axial compression load were thoroughly discussed and elucidated. Finally, some key factors that affect the buckling behaviors of cylindrical shells were carefully investigated, including material yield strength, the amplitude and topography of initial geometric imperfections, and the location of localized axial compression load along shell circumference. Results indicated that the distribution scope of localized axial compression load, shell material yield strength and the amplitude of initial geometric imperfections play a dominant role in the buckling behaviors of cylindrical shell under localized axial compression loads. The experimental and numerical investigations carried out in this research work can be regarded as a systematic attempt to study the buckling problems of thin-walled cylindrical shell structures under the more complex and practical axial load conditions. The results and conclusions obtained from this paper can also provide some guides for the design and application of thin-walled cylindrical shell in actual engineering. • Buckling tests of 21 cylindrical shells under localized axial compression loads were performed. • FEA model to study buckling behaviors of cylindrical shell under localized axial loads was established. • Buckling mechanism and load carrying capacity of cylindrical shell under localized axial load were elaborated. • Effects of some key factors on the buckling behaviors of cylindrical shell were discussed. [ABSTRACT FROM AUTHOR]

Abstract: Both the steric hindrance and the electronic effect are important factors for controlling the enantioselectivity in asymmetric catalysis. The substituent-dependent enantioselectivity in the asymmetric aziridination of chalcones catalyzed by 1,8-anthracene-linked bis-oxazoline (AnBOX) was rationalized to the π-stacking interaction between the ligand backbone and substrates and primarily confirmed by the use of bulky substrates and catalysts without aromatic backbones. The results provide important information for designing novel ligands and for understanding the influence of the electronic effect in asymmetric catalysis. [Copyright &y& Elsevier]

Abstract: A series of rigid backbone 1,8-anthracene-linked bis-oxazolines (AnBOXes) have been designed, synthesized, and evaluated in the catalytic asymmetric aziridination with [N-(p-toluenesulfonyl)imino]phenyliodinane (PhI nitrene source. The results indicate that highly enantioselective aziridination of chalcones catalyzed by an AnBOX and CuOTf complex with up to >99% ee and the opposite enantioselectivity, compared with the ligands of Evans et al., can be achieved. The enantioselectivity is substituent dependent with respect to chalcones. Chalcones with electron-donating substituents show higher enantioselectivities due to the stronger Lewis basicity of the oxygen of their carbonyl groups than those with electron-withdrawing substituents. The results also indicate that the coordination between the oxygen of the carbonyl group in chalcones and the ether group in alkenes with the copper in the catalyst is essential for high enantioselectivity, while the π–π stacking interaction between two reactants plays an importantly additional role for high enantioselectivity in asymmetric aziridination. An excellent backbone-controlled stereoselectivity was observed for the AnBOX ligands in asymmetric aziridination, as this will provide very important information for designing novel ligands. [Copyright &y& Elsevier]

Thin-walled cylindrical shell structure not only shows the highly efficient load carrying capacity but also is vulnerable to buckling instability failure. In practical application, these structures are usually subjected to localized axial compression load, which is a common but complex non-uniform loading case. Until now, the buckling behaviors of thin-walled cylindrical shells under this kind of compression loading condition are still unclear, and there are also few relevant investigations. In order to fill this research gap, in the first part of this series paper the experimental studies on the buckling behaviors of thin-walled cylindrical shells under localized axial compression loads were performed for the first time. The buckling tests of twenty-one steel cylindrical shells were carried out in this paper and some key experimental details were given. The strain curve, axial load–displacement curve, critical buckling load as well as the buckling modes of cylindrical shells under localized axial compression load were systematically discussed. Test results indicated that the localized axial compression load plays a pivotal role in the buckling behaviors of thin-walled cylindrical shell, not matter from the point of view of load carrying capacity, load–displacement curve or buckling mode. The experimental results obtained from this work can be served as a benchmark for related research in this field of buckling analysis of thin-walled cylindrical shells. • Buckling tests of 21 cylindrical shells under localized axial compression loads were performed. • FEA model to study buckling behaviors of cylindrical shell under localized axial loads was established. • Buckling mechanism and load carrying capacity of cylindrical shell under localized axial load were elaborated. • Effects of some key factors on the buckling behaviors of cylindrical shell were discussed. [ABSTRACT FROM AUTHOR]

This paper investigates the buckling behaviors of thin rectangular functionally graded carbon nanotubes reinforced composite (FG-CNTRC) plate subjected to the arbitrarily distributed partial edge compression loads. Three distribution types of carbon nanotubes (CNTs) are considered and the effective material properties of carbon nanotube reinforced composite are given according to the extended rule of mixture, in which the distribution uncertainty of CNTs is also taken into account. Based on the differential quadrature method (DQM) and work equivalent method, the pre-buckling in-plane stress distribution of thin rectangular FG-CNTRC plate are determined firstly. Then the accurate critical buckling loads and buckling modes of FG-CNTRC plate are consequently obtained. By comparing with the results in published literatures, the feasibility and accuracy of present numerical method are validated. Finally, the systematic parametric studies are carried out to elaborate the effects of distribution type, volume fraction and distribution uncertainty of CNTs as well as the distribution width, position and distribution type of partial edge compression loads on the buckling behaviors of thin rectangular FG-CNTRC plate for the first time. • A numerical method for buckling analysis of thin rectangular FG-CNTRC plate under arbitrarily distributed partial edge compression loads is developed. • The influence of CNTs distribution uncertainty in the matrix of FG-CNTRC plate is considered and discussed in details. • Effects of partial edge compression loads on the buckling behaviors of FG-CNTRC plate are studied for the first time. [ABSTRACT FROM AUTHOR]

Background & Aims Activation of WNT signaling promotes the invasive activities of several types of cancer cells, but it is not clear if it regulates the same processes in colorectal cancer (CRC) cells, or what mechanisms are involved. We studied the expression and function of OVOL2, a member of the Ovo family of conserved zinc-finger transcription factors regulated by the WNT signaling pathway, in intestinal tumors of mice and human beings. Methods We analyzed the expression of OVOL2 protein and messenger RNA in CRC cell lines and tissue arrays, as well as CRC samples from patients who underwent surgery at Xiamen University in China from 2009 to 2012; clinical information also was collected. CRC cell lines (SW620) were infected with lentivirus expressing OVOL2, analyzed in migration and invasion assays, and injected into nude mice to assess tumor growth and metastasis. Tandem affinity purification was used to purify the OVOL2-containing complex from CRC cells; the complex was analyzed by liquid chromatography, tandem mass spectrometry, and immunoprecipitation experiments. Gene promoter activities were measured in luciferase reporter assays. We analyzed mice with an intestine-specific disruption of Ovol2 ( Ovol2 flox/+ transgenic mice), as well as Apc min /+ mice; these mice were crossed and analyzed. Results Analysis of data from patients indicated that the levels of OVOL2 messenger RNA were significantly lower in colon carcinomas than adenomas, and decreased significantly as carcinomas progressed from grades 2 to 4. Immunohistochemical analysis of a tissue array of 275 CRC samples showed a negative association between tumor stage and OVOL2 level. Overexpression of OVOL2 in SW620 cells decreased their migration and invasion, reduced markers of the epithelial-to-mesenchymal transition, and suppressed their metastasis as xenograft tumors in nude mice; knockdown of OVOL2 caused LS174T cells to transition from epithelial to mesenchymal phenotypes. OVOL2 bound T-cell factor (TCF)4 and β-catenin, facilitating recruitment of histone deacetylase 1 to the TCF4–β-catenin complex; this inhibited expression of epithelial-to-mesenchymal transition–related genes regulated by WNT, such as SLUG , in CRC cell lines. OVOL2 was a downstream target of WNT signaling in LS174T and SW480 cells. The OVOL2 promoter was hypermethylated in late-stage CRC specimens from patients and in SW620 cells; hypermethylation resulted in OVOL2 down-regulation and an inability to inhibit WNT signaling. Disruption of Ovol2 in Apc min/+ mice increased WNT activity in intestinal tissues and the formation of invasive intestinal tumors. Conclusions OVOL2 is a colorectal tumor suppressor that blocks WNT signaling by facilitating the recruitment of histone deacetylase 1 to the TCF4–β-catenin complex. Strategies to increase levels of OVOL2 might be developed to reduce colorectal tumor progression and metastasis. [ABSTRACT FROM AUTHOR]

Water consumption by individual pigs can be an interesting indicator of their health. A method using machine vision is proposed to (a) recognise the presence of an individual pig within the drinking zone and (b) analyse the vision images to determine if the pig is drinking. First, isolation of an individual pig within the drinking zone is extracted from the topview of the set of video sequences for group-housed pigs. Next, the distance between the individual pig and the drink nipple is calculated and used to determine whether the individual pig is in contact with the drink nipple. If yes, the colour moments, area, perimeter and other features of the pig are extracted. Then the features are normalised. The individual pig is recognised by computing the Euclidean distance between the pig and the standard sample. The contact time between an individual pig and the drink nipple is used to determine whether the pig is drinking. The pigsty contains 7 pigs and is monitored in real-time, and 140 video clips containing images of the individual pigs while drinking are captured. The correct (drinking) recognition rate for individual pigs is 90.7%. Our method differs from traditional methods in that it avoids any disturbance to the pigs, and it can be used for the recognition of individual pigs within a stress-free environment. Our results can provide a reference point and direction for exploration of other behaviours of topview group-housed pigs. [ABSTRACT FROM AUTHOR]

Increased phospholipid transfer protein (PLTP) activity has been found to be associated with obesity, and metabolic syndrome in humans. However, whether or not PLTP has a direct effect on insulin sensitivity and obesity is largely unknown. Here we analyzed the effect by using PLTP knockout (PLTP−/−) mouse model. Although, PLTP−/− mice have normal body-weight-gain under chow diet, these mice were protected from high-fat-diet-induced obesity and insulin resistance, compared with wild type mice. In order to understand the mechanism, we evaluated insulin receptor and Akt activation and found that PLTP deficiency significantly enhanced phosphorylated insulin receptor and Akt levels in high-fat-diet fed mouse livers, adipose tissues, and muscles after insulin stimulation, while total Akt and insulin receptor levels were unchanged. Moreover, we found that the PLTP deficiency induced significantly more GLUT4 protein in the plasma membranes of adipocytes and muscle cells after insulin stimulation. Finally, we found that PLTP-deficient hepatocytes had less sphingomyelins and free cholesterols in the lipid rafts and plasma membranes than that of controls and this may provide a molecular basis for PLTP deficiency-mediated increase in insulin sensitivity. We have concluded that PLTP deficiency leads to an improvement in tissue and whole-body insulin sensitivity through modulating lipid levels in the plasma membrane, especially in the lipid rafts. • PLTP-/- mice were protected from high-fat-diet-induced obesity and insulin resistance, compared with wild type mice. • PLTP deficiency stimulates IR and Akt phosphorylation and enhances GluT4 expression in high fat diet-fed animals. • PLTP deficiency decreases the levels of sphingomyelins and free cholesterols in hepatic plasma membranes and lipid rafts. [ABSTRACT FROM AUTHOR]

• Chiral zinc amidate catalyzes additions of Et 2 Zn to aldehydes in high yields and mediocre ee. • Carboxamides bearing a phosphine oxide group work as bifunctional ligands. • Spiro[indane-1,2′-pyrrolidin]-5′-one constitutes a rigid backbone for effective chiral ligands. A series of bifunctional spiro ligands bearing "carboxamide–phosphine oxide" groups and ethylzinc carboxamidates from these ligands as catalysts for Et 2 Zn additions to aldehydes were reported. Excellent yields were obtained with moderate ee′s in Et 2 Zn additions to benzaldehyde derivatives, implying effectiveness of our newly designed catalytic structures as well as mediocre stereocontrol by these chiral ligands. Possible transition states were suggested based on the crystal structures of two ligands. [ABSTRACT FROM AUTHOR]

Buckling behavior of cylindrical shells with measured settlement under axial compression has been researched and analyzed in this paper. Using the method of Fourier series expansion, the measured settlement data is transformed into differential settlement. Applying the finite element simulation method, the differential settlement is applied to bottom of the cylindrical shell in order to simulate behavior of the cylindrical shell under differential settlement. Based on the deformed cylindrical shell caused by settlement, the finite element simulation method is applied to research buckling behavior of the cylindrical shell under axial compression considering the geometric nonlinearity and large deformation. The meridional membrane stress distribution in the circumferential direction of the cylindrical shell under differential settlement is obtained and compared with the differential settlement distribution. Effects of liquid storage on buckling behavior of the cylindrical shell are researched by applying hydrostatic pressure to the inner surface. Parametric analysis is carried out to research the effects of diameter-thickness ratio and height-diameter ratio of the cylindrical shell on the axial buckling capability. Results show that the cylindrical shell will be subjected to deformation and meridional membrane stress because of the differential settlement and the critical axial buckling load will be decreased then. Liquid storage is helpful for the cylindrical shell to remain stable. The cylindrical shell with larger height-diameter ratio and smaller diameter-thickness ratio is more capable to resist buckling under axial compression following differential settlement. [ABSTRACT FROM AUTHOR]

Autophagy modulation has been considered as a potential therapeutic strategy for lung diseases. The PI3K-Akt-mTOR pathway may be one of the main targets for regulation of autophagy. We previously reported that a PI3 K/mTOR dual inhibitor PF-04691502 suppressed hepatoma cells growth in vitro . However, it is still unclear whether PF-04691502 induces autophagy and its roles in DNA damage and cell death in human lung cancer cells. In this study, we investigate the effects of PF-04691502 on the autophagy and its correlation with cell apoptosis and DNA damage in non-small-cell lung cancer (NSCLC) cell lines. PF-04691502 efficiently inhibited the phosphorylation of Akt and showed dose-dependent cytotoxicity in A549 and H1299 cells. PF-04691502 also triggered apoptosis and the cleavage of caspase-3 and PARP. Phosphorylated histone H2AX (γ-H2AX), a hallmark of DNA damage response, was dramatically induced by PF-04691502 treatment. By exposure to PF-04691502, A549 cells acquired a senescent-like phenotype with an increase in the level of β-galactosidase. Furthermore, PF-04691502 enhanced the expression of LC3-II in a concentration-dependent manner. More interestingly, effects of PF-04691502 on toxicity and DNA damage were remarkably increased by co-treatment with an autophagy inhibitor, chloroquine (CQ), in human lung cancer cells. These data suggest that a strategy of blocking autophagy to enhance the activity of PI3 K/mTOR inhibitors warrants further attention in treatment of NSCLC cells. [ABSTRACT FROM AUTHOR]

The regioselectivity of the o -semidine, p -semidine, and diphenyline rearrangements of unsymmetrical N , N ′-diarylhydrazines was studied experimentally. The results indicate that their electron-rich nitrogen atom is first protonated and then the electron-poor non-protonated nitrogen atom undergoes an N [1,3]-sigmatropic shift to the ortho -position of the electron-rich aryl rings, generating key intermediates. The intermediates can undergo (1) a direct proton transfer to give o -semidines, (2) a second N [1,3]-shift of the electron-poor nitrogen atom and then proton transfer to furnish p -semidines, and (3) a [3,3]-sigmatropic shift and subsequent proton transfer to yield diphenylines. It is the first N [1,3]-sigmatropic shift step that plays an important role in controlling the regioselectivity in the three rearrangements, further determining the structures of o -semidines, p -semidines, and diphenylines. The current results provide new insights into the o / p -semidine and diphenyline rearrangements and useful information for controlling and predicting the structures of the rearrangement products. [ABSTRACT FROM AUTHOR]

The weak acid has been identified as an efficient basicity-mask to overcome the basicity barrier imparted by aliphatic amines in the Pd-catalyzed hydroaminocarbonylation, which enables both aromatic and aliphatic amines to be applicable in the palladium-catalyzed hydroaminocarbonylation reaction. Notably, by using this protocol, the marketed herbicide of Propanil and drug of Fentanyl could be easily obtained in a one-pot manner. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2 ) attenuates the development of atherosclerosis in mouse models. We aimed to examine the effects of H 2 on atherosclerotic plaque stability. Low-density lipoprotein receptor-knockout (LDLR −/− ) mice fed an atherogenic diet were dosed daily with H 2 and/or simvastatin. In vitro studies were carried out in an oxidized-LDL (ox-LDL)-stimulated macrophage-derived foam cell model treated with or without H 2 . H 2 or simvastatin significantly enhanced plaque stability by increasing levels of collagen, as well as reducing macrophage and lipid levels in plaques. The decreased numbers of dendritic cells and increased numbers of regulatory T cells in plaques further supported the stabilizing effect of H 2 or simvastatin. Moreover, H 2 treatment decreased serum ox-LDL level and apoptosis in plaques with concomitant inhibition of endoplasmic reticulum stress (ERS) and reduction of reactive oxygen species (ROS) accumulation in the aorta. In vitro, like the ERS inhibitor 4-phenylbutyric acid, H 2 inhibited ox-LDL- or tunicamycin (an ERS inducer)-induced ERS response and cell apoptosis. In addition, like the ROS scavenger N -acetylcysteine, H 2 inhibited ox-LDL- or Cu 2+ (an ROS inducer)-induced reduction in cell viability and increase in cellular ROS. Also, H 2 increased Nrf2 (NF-E2-related factor-2, an important factor in antioxidant signaling) activation and Nrf2 small interfering RNA abolished the protective effect of H 2 on ox-LDL-induced cellular ROS production. The inhibitory effects of H 2 on the apoptosis of macrophage-derived foam cells, which take effect by suppressing the activation of the ERS pathway and by activating the Nrf2 antioxidant pathway, might lead to an improvement in atherosclerotic plaque stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional nanoplatform (g-CPFD) based on g-C 3 N 4 quantum dots is synthesized. • The g-CPFD achieves chemo-photodynamic combination therapy in one system. • The g-CPFD exhibits folate receptor-mediated targeting ability. • The g-CPFD is traceable and exhibits pH-responsive release property. Graphitic carbon nitride quantum dots (g-CNQDs) have shown great potential in imaging, drug delivery and photodynamic therapy (PDT). However, relevant research on g-CNQDs for PDT or drug delivery has been conducted separately. Herein, we develop a g-CNQDs-based nanoplatform (g-CPFD) to achieve simultaneously imaging and chemo-photodynamic combination therapy in one system. A g-CNQDs-based nanocarrier (g-CPF) is first prepared by successively introducing carboxyamino-terminated oligomeric polyethylene glycol and folic acid onto the surface of g-CNQDs via two-step amidation. The resultant g-CPF possesses good physiological stability, strong blue fluorescence, desirable biocompatibility, and visible light-stimulated reactive oxygen species generating ability. Further non-covalently loaded doxorubicin enables the system with chemotherapy function. Compared with free doxorubicin, g-CPFD expresses more efficient chemotherapy to HeLa cells due to improved folate receptor-mediated cellular uptake and intracellular pH-triggered drug release. Furthermore, g-CPFD under visible light irradiation shows enhanced inhibition on the growth of cancer cells compared to sole chemotherapy or PDT. Thus, g-CPFD exhibits exceptional anti-tumor efficiency due to folate receptor-mediated targeting ability, intracellular pH-triggered drug release and a combined treatment effect arising from PDT and chemotherapy. Moreover, this nanoplatform benefits imaging-guided drug delivery because of inherent fluorescent properties of doxorubicin and g-CPF, hence achieving the goal of imaging-guided chemo-photodynamic combination treatments. [ABSTRACT FROM AUTHOR]

Due to high sensitivity to various imperfections, buckling loads of thin-walled cylindrical shells subjected to axial load vary dramatically. In order to predict lower-bound buckling loads for axially loaded cylindrical shells rationally, a probabilistic analysis approach named Probabilistic Random Perturbation Load Approach (PRPLA) is developed in this study. Firstly, a Back-Propagation Neural Network (BPNN) based method is established to describe measured imperfection patterns. Next, Random Single Perturbation Load Approach (RSPLA) is loaded upon BPNN-based depicted traditional imperfection patterns to construct a stochastic dimple imperfection. The aforementioned scattering traditional imperfections, as well as a variety of scattering non-traditional imperfections, are then sampled using Monte-Carlo simulation to generate cylindrical shell models differentiating from a nominal one. The probabilistic distribution of lower-bound buckling loads is obtained by finite element analysis. A nominal shell's realistic lower-bound buckling load is determined by choosing a specified reliability level lastly. The results show that describing measured imperfection patterns via BPNN is very close to real ones, and PRPLA presented is an improved method to find lower-bound buckling loads efficiently compared with NASA SP-8007 and many commonly used numerical approaches. • Probabilistic Random Perturbation Load Approach is developed to predict lower-bound axial loads for isotropic cylinders. • Back-Propagation Neural Network shows superiority when describing the surface morphology based on measured imperfections. • The yielded lower-bound buckling loads are less conservative than the ones by NASA-SP 8007 while still being robust. [ABSTRACT FROM AUTHOR]

Inconsistencies exist with regard to the influence of dehydroepiandrosterone (DHEA) supplementation on insulin-like growth factor 1 (IGF-1) levels. The inconsistencies could be attributed to several factors, such as dosage, gender, and duration of intervention, among others. To address these inconsistencies, we conducted a systematic review and meta-analysis to combine findings from randomized controlled trials (RCTs) on this topic. Electronic databases (Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar) were searched for relevant literature published up to February 2020. Twenty-four qualified trials were included in this meta-analysis. It was found that serum IGF-1 levels were significantly increased in the DHEA group compared to the control (weighted mean differences (WMD): 16.36 ng/ml, 95% CI: 8.99, 23.74; p =.000). Subgroup analysis revealed that a statistically significant increase in serum IGF-1 levels was found only in women (WMD: 23.30 ng/ml, 95% CI: 13.75, 32.87); in participants who supplemented 50 mg/d DHEA (WMD: 15.75 ng/ml, 95% CI: 7.61, 23.89); in participants undergoing DHEA intervention for >12 weeks (WMD: 17.2 ng/ml, 95% CI: 8.02, 26.22); in participants without an underlying comorbidity (WMD: 19.11 ng/ml, 95% CI: 10.69, 27.53); and in participants over the age of 60 years (WMD: 19.79 ng/ml, 95% CI: 9.86, 29.72). DHEA supplementation may increase serum IGF-I levels especially in women and older subjects. However, further studies are warranted before DHEA can be recommended for clinical use. • Supplementation with DHEA may increase serum IGF-I levels. • The effects occur especially in women and older subjects. • The findings cannot be endorsed as a substantial factor in clinical practice. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2) has antioxidant effects. The pharmacologic function of H 2 in platelets is not yet clear. Therefore, in this study we sought to investigate the inhibitory effects of H 2 on in vitro platelet activation and in vivo prevention of thrombus formation. After platelets were incubated with H 2 -rich saline (HRS), platelet adhesion in whole human blood was assessed in fibrinogen-coated perfusion chambers, while rat platelet aggregation induced by ADP, collagen and H 2 O 2 was detected through light transmission aggregometry. The level of P-selectin, thromboxane B 2 , nitric oxide (NO), malondialdehyde, reactive oxygen species (ROS), cGMP, extracellular signal-regulated kinases 1 and 2 (p-ERK1/2), and fibrinogen binding to platelets were evaluated in vitro. Besides, the in vivo effects were examined in arterio-venous shunt thrombosis, FeCl 3 -induced artery thrombus formation, and tail bleeding time in mice and rats. HRS prolonged tail bleeding time in mice and rats, decreased thrombus weight and prolonged the time to occlusion in rat and mouse thrombosis models in vivo and inhibited platelet adhesion as well as aggregation in vitro. Additionally, HRS decreased P-selectin expression, release of thromboxane B 2 , ROS, and fibrinogen binding, but enhanced NO levels in H 2 O 2 -exposed platelets. HRS also decreased malondialdehyde levels in plasma of the rat arterial thrombosis or H 2 O 2 -exposed platelet model. Moreover, HRS increased cGMP level, decreased p-ERK1/2 (diminished with KT5823) in the platelets stimulated by H 2 O 2. These results suggest that H 2 has antithrombotic effects, which may be due to its antioxidant property and subsequent inhibition of platelet activation via NO/cGMP/PKG/ERK pathway. [ABSTRACT FROM AUTHOR]