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Cyclopropanols and cyclopropylamines not only serve as important structural motifs in medicinal chemistry but also show diverse reactivities in organic synthesis. Owing to the high ring strain energy, the development of a general protocol from stable and readily available starting materials to afford these cyclopropyl derivatives remains a compelling challenge. Herein, we describe that a Ti-based catalyst can effectively promote the diastereoselective syntheses of cyclopropanols and cyclopropylamines from widely accessible carboxylic derivatives (acids, esters, amides) with terminal olefins. To the best of our knowledge, this method represents the first example of direct converting alkyl carboxylic acids into cyclopropanols. Distinct from conventional studies in Ti-mediated cyclopropanations with reactive alkyl Grignard reagents as nucleophiles or reductants, this protocol utilizes Mg and Me

Enabled by the newly developed ligand, Ming-Phos, the first example of palladium-catalyzed highly enantioselective coupling of racemic propargylic benzoates with organoboronic acids for chiral allenes synthesis has been developed. Excellent asymmetric induction has been achieved with a decent substrate scope. Synthetic potentials for the construction of polycyclic compounds with multiple chiral centers have been demonstrated.

A highly efficient Pd/H+-cocatalyzed kinetic resolution reaction of tertiary propargylic alcohols has been reported. The method provides an efficient approach to prepare a series of propargylic alcohols bearing a chiral quaternary stereocenter in good yields and remarkable enantioselectivities (93–>99% ee) under mild and operationally simple reaction conditions tolerating a broad range of functional groups. The practicality of this method has been demonstrated via the 4-gram-scale synthesis of chiral propargylic alcohol (S)-1a.

Chirality is one of the most important types of steric information in nature. In addition to central chirality, axial chirality has been catching more and more attention from scientists. However, although much attention has recently been paid to the creation of axial chirality and the chirality transfer of allenes, no study has been disclosed as to the memory of such an axial chirality. The reason is very obvious: the chiral information is stored over three carbon atoms. Here, the first example of the memory of chirality (MOC) of allenes has been recorded, which was realized via an optically active alkylidene-π-allyl iridium intermediate, leading to a highly stereoselective electrophilic allenylation with amines. Specifically, we have established the transition metal-mediated highly stereoselective 2,3-allenylation of amines by using optically active 2,3-allenyl carbonates under the catalysis of a nonchiral iridium(iii) complex. This method is compatible with sterically bulky and small substituents on both amines and 2,3-allenyl carbonates and furnishes the desired optically active products with a high efficiency of chirality transfer. Further mechanistic experiments reveal that the isomerization of the optically active alkylidene-π-allyl iridium intermediate is very slow., Chirality is one of the most important types of steric information in nature.

Efficient enantioselective construction of fully substituted allenes from simple starting materials is still a fundamental challenge due to the difficulty to discriminate between the four substituents at the 1- and 3-positions of the three-carbon axis of chirality. Here, we report a straightforward catalytic asymmetric synthesis of tetrasubstituted 2,3-allenoic acids from readily available racemic propargylic alcohols. Enabled by the co-catalysis of palladium and a Bronsted acid in the presence of a commercially available chiral ligand (DTBM-SEGphos) and an achiral monophosphine supporting ligand (PPh3), the kinetic resolution of propargylic alcohols proceeded efficiently in the presence of water and 1 atm CO, affording tetrasubstituted 2,3-allenoic acids in excellent enantioselectivity and atom economy with a good functional group compatibility. Performing a second kinetic resolution on the unreacted alcohol gave access to the other enantiomer of the product. These allenes are precursors to compounds with quaternary carbon centres and other chiral tetrasubstituted allene building blocks, which are of great interest. Asymmetric routes for the formation of tetrasubstituted allenes are scarce and limited in scope. Now, a catalytic asymmetric process is reported giving access to tetrasubstituted allenes from readily available propargylic alcohols, and a potential role for an achiral supporting ligand is postulated.

A palladium-catalyzed C–O bond formation reaction between phenols and allenylic carbonates to give 2,3-allenic aromatic ethers with decent to excellent yields under mild reaction conditions has been described. A variety of synthetically useful functional groups are tolerated and the synthetic utility of this method has been demonstrated through a series of transformations of the allene moiety. By applying this reaction as the key step, the total syntheses of naturally occurring allenic aromatic ethers, eucalyptene and terricollene A (first synthesis; 4.5 g gram scale), have been accomplished., A palladium-catalyzed C–O bond formation reaction between phenols and allenylic carbonates to give 2,3-allenic aromatic ethers with decent to excellent yields under mild reaction conditions has been described.

Two new coordination polymers [Co2(L)2(4,4′-bipy)(H2O)2](DMA)2 (1, 4,4′-bipy = 4,4′-bipyridine, H2L = 4-(1H-pyrazole-4-yl)benzoic acid) and [Cu2(L)2(4,4′-bipy)](DEF)3 (2, DEF = N, N-diethylformamide), have been synthesized via solvothermal reaction of M(NO3)2·6H2O (M = Co for 1 and Cu for 2) with the pyrazolate/carboxylate ligand and the 4,4′-bipy linker. Both coordination polymer architectures in nanoscale regimes have been prepared and determined via PXRD and SEM, and the cytotoxicity of them against the human cardiac myoma cells H9C2 has been evaluated via the MTT assay with the cisplatin as the reference drug, which demonstrates better anticancer activities of the both nano architectures than those of their samples in micro regimes.

Objective To investigate the treatment experience of rectal cancer patients with excessively extended surgery after neoadjuvant chemoradiotherapy. Methods Seven cases of rectal cancer patients admitted to our hospital from 2014 to 2016 with excessively extended surgical intervention (6 to 13 months) after neoadjuvant chemoradiotherapy were included in the present study. All of the patients were treated with radical surgery, and the operation effect and postoperative complications were observed. Results Three patients underwent anterior resection of the rectum (Dixon), including 2 cases of anastomotic leakage; 3 cases occurred intestinal rupture during operation, 1 of them complicated with postoperative pelvic abscess; there were 4 cases complicated with incision infection or liquefaction. No presacral venous plexus hemorrhage occurred. Conclusion Excessively extended surgery after neoadjuvant chemoradiotherapy increases the difficulty of operations and the occurrence of postoperative complications in patients with rectal cancer. DOI: 10.11855/j.issn.0577-7402.2018.01.12

The combined value of RDW and GRACE risk score for cardiovascular prognosis in ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been fully investigated. This study was designed to explore the combined value of RDW and GRACE risk score on predicting long-term major adverse cardiac event (Mace) in STEMI patients undergoing primary PCI. This study included 390 STEMI patients. The primary endpoint at the (33.5 ± 7.1) months follow-up was composed of cardiac death and nonfatal myocardial infarction. The relationship between clinical parameters and clinical outcomes was evaluated using Cox regression model and receiver operating characteristic (ROC) analysis. Mace occurred in 126 (32.3%) patients including 54 (13.8%) cardiac deaths and 72 (18.5%) nonfatal myocardial infarctions. Patients in Mace group had significantly higher RDW and GRACE score than the patients in non-Mace group. According to the Cox model, RDW and GRACE score were the most important independent predictors of Mace and cardiac death. The best cut-off value for RDW to predict the occurrence of primary events was 13.25% (AUC = 0.694, 95% CI:0.639–0.750, P < 0.001) and that for GRACE score was 119.5 (AUC = 0.721, 95% CI:0.666–0.777, P < 0.001). The combination of RDW and GRACE score were more valuable (AUC = 0.775, 95% CI: 0.727–0.824, P < 0.001). Kaplan–Meier analysis provided significant prognostic information with the highest risk for cardiac death (Log-Rank χ2 = 24.684, P < 0.001) in group with both high RDW (> 13.25%) and high GRACE score (> 119.5). The combination of RDW level and GRACE score may be valuable and simple independent predictors of Mace and cardiac death in STEMI patients undergoing primary PCI. They may be useful tools for risk stratification and may indicate long-term clinical outcomes.

A straightforward protocol for the synthesis of tetra-substituted 2,3-allenoic acids via a catalytic carboxylation of the readily available propargylic alcohols in the presence of CO using palladium and a Bronsted acid as the cocatalysts has been established. This atom-economical reaction proceeded under mild conditions to afford 2,3-allenoic acids with a broad scope tolerating useful functional groups.

A highly regio-, diastereo- and enantioselective addition of 2-acyl imidazoles or 2-acyl pyridines with allenes promoted by Rh/Lewis acid synergistically catalytic system is described. This atom economic approach leads to the formation of the branched allylic alkylated products including acyclic quaternary all-carbon stereogenic centres in good yields with good to excellent diastereo- and enantioselectivities. Kinetic studies reveal that the rate-determining step in this process is the oxidative addition of Rh(I) with C-H bond.

Herein we describe an efficient protocol for the regioselective addition of 1,3-dicarbonyl compounds to internal alkynes catalyzed by rhodium/Lewis acid catalysts. The corresponding branched/linear allylic alkylation products could be selectively obtained in good yields. Rh–H species were considered to be generated by direct C–H oxidative addition of 1,3-dicarbonyl compounds with rhodium catalyst with the assistance of Lewis acid. Moreover, a retro-allylic alkylation process was observed in this transformation.

A total of 99 full-scale field load tests at 22 sites were compiled for this study to elucidate several issues related to the load-displacement behaviour of belled piers under axial uplift loading, including (1) interpretation criteria to define various elastic, inelastic, and "failure" states for each load test from the load-displacement curve; (2) generalized correlations among these states and determinations to the predicted ultimate uplift resistances; (3) uncertainty in the resistance model factor statistics required for reliability-based ultimate limit state (ULS) design; (4) uncertainty associated with the normalized load-displacement curves and the resulting model factor statistics required for reliability-based serviceability limit state (SLS) design; and (5) variations of the combined ULS and SLS model factor statistics for reliability-based limit state designs. The approaches discussed in this study are practical and grounded realistically on the load tests of belled piers with minimal assumptions. The results on the characterization and uncertainty of uplift load.displacement behaviour of belled piers could be served as to extend the early contributions for reliability-based ULS and SLS designs.

// Wei-feng Zheng 1 , Ting-ting Ji 1 , Yong Lin 1 , Rong-zhou Li 1 1 Department of Gastroenterology, Rui’an People’s Hospital, Third Affiliated Hospital of Wenzhou Medical University, Wenzhou 325200, Zhejiang Province, China Correspondence to: Rong-zhou Li, email: drlirz@sina.com Keywords: gastric cancer, lymph node count, survival analysis, SEER Received: March 17, 2016 Accepted: May 20, 2016 Published: June 06, 2016 ABSTRACT The retrieved lymph node (LN) count has been validated as a prognostic factor in various cancers. However, the interaction between LN counts and patients’ prognosis in gastric cancer with negative-LN metastasis is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Patients operated on for gastric cancer at N0 stage between 2004 and 2012 were identified from the SEER database. The association between the LN counts and survival was assessed using the Cox proportional hazards model. Patients were stratified into 1−4, 5−13, and > 13 subgroups according to LN count cut-off values determined by X-tile program, with the 5-year cause specific survival (CSS) rate of 64.8%, 72.5%, and 79.4%, respectively. LN count was also validated as an independently prognostic factor in multivariate Cox analysis ( P < 0.001). In addition, nomograms including LN counts on CSS were established according to all significant factors, and the c-index was 0.703 (95% CI: 0.672−0.734). Further study indicated that patients with no LN metastasis had a decreased risk of death for each patient with LN examined up to approximately 14 LNs. Collectively, our study firmly demonstrated that the number of the retrieved LNs count was an independent prognostic factor for gastric cancer with no LN metastasis. The higher the LN count, the better the survival would be; the best CSS was observed on the LN count more than 14.

The clinical use of doxorubicin (DOX) is limited by its toxic effect. However, there is no specific drug that can prevent DOX-related cardiac injury. C1qTNF-related protein-6 (CTRP6) is a newly identified adiponectin paralog with many protective functions on metabolism and cardiovascular diseases. However, little is known about the effect of CTRP6 on DOX-induced cardiac injury. The present study aimed to investigate whether CTRP6 could protect against DOX-related cardiotoxicity. To induce acute cardiotoxicity, the mice were intraperitoneally injected with a single dose of DOX (15 mg/kg). Cardiomyocyte-specific CTRP6 overexpression was achieved using an adenoassociated virus system at 4 weeks before DOX injection. The data in our study demonstrated that CTRP6 messenger RNA and protein expression were decreased in DOX-treated hearts. CTRP6 attenuated cardiac atrophy induced by DOX injection and inhibited cardiac apoptosis and improved cardiac function in vivo. CTRP6 also promoted the activation of protein kinase B (AKT/PKB) signaling pathway in DOX-treated mice. CTRP6 prevented cardiomyocytes from DOX-induced apoptosis and activated the AKT pathway in vitro. CTRP6 lost its protection against DOX-induced cardiac injury in mice with AKT inhibition. In conclusion, CTRP6 protected the heart from DOX-cardiotoxicity and improves cardiac function via activation of the AKT signaling pathway.

In terms of good optical properties and high thermal stability, Mo/Si3N4/Mo/Si3N4/SiO2 coatings based on metal/dielectric multilayer structure were adapted to the solar selective coating at high operating temperatures. The coatings exhibited high solar absorptance in the range of 0.924 ~ 0.936 and low thermal emittance of 0.114 ~ 0.118. The coatings deposited on quartz substrates were thermally stable up to 625 °C in air for 2 h, while they were degraded at 650 °C from the characterization of the absorptance and emittance. The degradation of the coatings was mainly due to the oxidation of molybdenum in air, which was confirmed by Raman spectroscopy. Compared with the thermal stability in air, the coatings were much more stable in vacuum under high temperature. The remarkable thermal stability of the Mo/Si3N4/Mo/Si3N4/SiO2 coatings in air and in vacuum makes them suitable to be applied at high temperature applications.

According to the mechanics characteristics of inclined plane foundations in transmission line project, rotary theories of spatial coordinate system were used. Load conversion method on inclined plane foundation is analyzed and obtained to get normal section bearing capacity of the column. Meanwhile, the derivation steps and calculation formulas are shown.

Rock anchor foundation can be widely used for the practical transmission line engineering in mountain areas. On strong-weathered sandstone ground, ten sets of uplift static load test of single rock anchor foundation were carried out. Based on the testing results, the typical failure modes and the ultimate uplift bearing capacity of foundations were obtained. Internal force distribution and effective anchorage depth were investigated through stain measurements. Design parameters of rock anchor foundation on sandstone ground were proposed, which can provide a reference for transmission line engineering design.

A highly regio- and stereoselective Rh-catalyzed intermolecular head-to-head [2 + 2] cycloaddition of allenamides was developed. The intermolecular cycloadducts, trans-dimethylenecyclobutane-1,2-diamine derivatives, were achieved in good yields with high regioselectivity and stereoselectivity.

Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a recently identified and potentially useful plasma biomarker for cardiovascular diseases. However, its role in peripheral arterial disease (PAD) remains unclear. The objective of this study was to assess the independent association of Lp-PLA2 and other inflammatory markers with the reduced ankle-brachial blood pressure index (ABI), a marker of PAD. We performed a cross-sectional study in 982 individuals aged ≥40 years who were recruited from the First Affiliated Hospital of Zhengzhou University. PAD was defined as an ABI

Transmission line foundation engineering inevitably encounters the special geological conditions in salt lake area, such as strong corrosion of saline soil, weakness of foundation soil and high water table of groundwater. In-situ tests on bearing characteristics of the selected pad and chimney foundation were conducted. Ultimate uplift bearing capacity and ultimate compressive bearing capacity of the pad and chimney foundation in salt lake are obtained, which can verify the rationality and reliability for its engineering popularization.

Large-jointed rock mass is the main geological condition of transmission lines of Qingyuan Regions in Guangdong Province. The bolt foundations haven’t be studied and applied in this geological condition. Static load tests of 15 single-bolt foundations and 8 group-bolt foundations were carried out. Experiment study shows that the mechanical characteristics of bolt foundation are suitable for transmission lines in large-jointed rock mass. The design parameters of anchor bar in large-jointed rock mass are derived from the measured data:τa>2359kPa, τb>618kPa, τc>42kPa.

A highly regio- and stereoselective Rh-catalyzed intermolecular head-to-head [2 + 2] cycloaddition of allenamides was developed. The intermolecular cycloadducts, trans-dimethylenecyclobutane-1,2-diamine derivatives, were achieved in good yields with high regioselectivity and stereoselectivity.

Through the orthogonal test in which stainless steel 316 was milled with high speed by solid cemented carbide end cutter, the milling force was measured. By multiple linear regression method, the prediction formula of the milling forces of stainless steel 316 was found. In addition, this study validates to significant degree of the formula meeting the actual condition, which can provide a reference to better selection of cutting parameter in advance and the design of high-speed milling cutter.

This paper presents an efficient VLSI architecture of the contest-based adaptive variable length code (CAVLC) decoder with power optimized for the H.264/advanced video coding (AVC) standard. In the proposed design, according to the regularity of the codewords, the first one detector is used to solve the low efficiency and high power dissipation problem within the traditional method of table-searching. Considering the relevance of the data used in the process of runbefore’s decoding, arithmetic operation is combined with finite state machine (FSM), which achieves higher decoding efficiency. According to the CAVLC decoding flow, clock gating is employed in the module level and the register level respectively, which reduces 43% of the overall dynamic power dissipation. The proposed design can decode every syntax element in one clock cycle. When the proposed design is synthesized at the clock constraint of 100 MHz, the synthesis result shows that the design costs 11 300 gates under a 0.25 µm CMOS technology, which meets the demand of real time decoding in the H.264/AVC standard.