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558 Background: Transarterial chemoembolization (TACE) is one of the standard treatments for patients with intermediate-stage hepatocellular carcinoma (HCC). The combination of immune checkpoint inhibitors (ICIs) and lenvatinib has shown to be an effective regimen in patients with unresectable HCC (uHCC). In this study, we aim to investigate the efficacy and safety of combination of Envafolimab (a novel, single-domain PD-L1 antibody) with Lenvatinib plus TACE in uHCC patients. Methods: This is a prospective, open-label, single-arm, phase 2 study. Adults with confirmed uHCC with BCLC stage B or C, Eastern Cooperative Oncology Group performance status 0 or 1, Child–Pugh scored ≤7 and no previous systemic treatment for HCC are eligible. Patients will receive Lenvatinib once daily plus Envafolimab every 3 weeks plus TACE. TACE will be conducted repeatedly every 6 weeks on demand according to investigators’ consideration, mainly based on the proportion of viable tumors. Imaging evaluation will be conducted every 6 weeks. The primary endpoint is objective response rate (ORR). Disease control rate (DCR), duration of response (DoR), progression free survival (PFS), overall survival (OS) and safety are evaluated as secondary endpoints (NCT05213221). Results: forty patients were consecutively enrolled from March, 2022 to September 2022. The median age was 54.5 years. At present, thirty-six patients were included for efficacy analysis, and forty for safety evaluation. Number of patients with BCLC stage B and C was 17(47.2%) and 19 (52.8%), respectively. 13 (36.1%) patients presented with portal vein tumor thrombus (PVTT) and 2 (5.6%) patient presented with hepatic vein tumor thrombus (HVTT). The ORR was 36.1% and 80.6%, and DCR was 77.8% and 83.3%, based on RECIST v1.1 and modified RECIST respectively. 11 patients reached the standard of conversion to resectable HCC and received radical resection. The most common TRAEs were elevated AST (75%), elevated ALT (65%) and leukopenia (42.5%). No treatment-related deaths occurred. The survival data are not mature at present. Conclusions: Envafolimab plus Lenvatinib combined with TACE is a promising and tolerable therapeutic regimen for patients with BCLC B/C unresectable HCC. Clinical trial information: NCT05213221 .

The discrete element method (DEM) often uses the angle of repose to study the microscopic parameters of particles. This paper proposes a multi-objective optimization method combining realistic modeling of particles and image analysis to calibrate gravel parameters, after obtaining the actual static angle of repose (αAoR_S) and dynamic angle of repose (βAoR_D) of the particles by physical tests. The design variables were obtained by Latin hypercube sampling (LHS), and the radial basis function (RBF) surrogate model was used to establish the relationship between the objective function and the design variables. The optimized design of the non-dominated sorting genetic algorithm II (NSGA-II) with the actual angle of repose measurements was used to optimize the design to obtain the best combination of parameters. Finally, the parameter set was validated by a hollow cylinder test, and the relative error between the validation test and the optimized simulation results was only 3.26%. The validation result indicates that the method can be reliably applied to the calibration process of the flow parameters of irregular gravel particles. The development of solid–liquid two-phase flow and the wear behavior of centrifugal pumps were investigated using the parameter set. The results show that the increase in cumulative tangential contact forces inside the volute of centrifugal pumps makes it the component most likely to develop wear behavior. The results also illustrate the significant meaning of the accurate application of the discrete element method for improving the efficient production of industrial scenarios.

Based on the concentrations of the trace elements, rare earth elements (REE), and Sr isotopic compositions in reef carbonates from the well ‘Xike-1’ reef core of the Xisha Islands, the constraints on sediment provenance and paleoenvironment were defined. Variations of the terrigenous input into the paleoseawater were traced in detail and the paleoenvironment and sediment provenance were further investigated. The results show that the HREE/LREE values in the reef carbonates are negatively associated with their Th and Al concentrations; however, their Al and Th concentrations show positive correlation. The lowest 87Sr/86Sr values in the reef carbonates generally coincide with the lowest values of Al, Th concentrations and the highest values of HREE/LREE. These data indicate that the HREE/LREE, Al concentrations, and Th concentrations of the reef carbonates are useful indexes for evaluating the influence of the terrigenous inputs on the seawater composition in the study area. From top to bottom, the changing process of the HREE/LREE values and Al, Th concentrations can be divided into 6 intervals; they are H1 (0–89.30 m, about 0–0.11 Myr), L1 (89.30–198.30 m, about 0.11–2.2Myr), H2 (198.30–374.95 m, about 2.2–5.3Myr), D (374.95–758.40 m, about 5.3–13.6 Myr), L2 (758.40–976.86m, about 13.6–15.5Myr), and H3 (976.86–1200.00m, about 15.5–21.5Myr). Moreover, the changing trend of the HREE/LREE values coincides with that of the seawater δ13C values recorded by benthonic foraminiferal skeletons from the drill core of ODP site 1148 in the South China Sea (SCS), but not with that of the seawater δ18O values. The high uplifting rates of the Qinghai-Tibet Plateau coincide with the high Th and Al concentrations and the low HREE/LREE values in the reef carbonates. These data indicate that the main factors controlling the changes of terrigenous flux in the SCS are the tectonic activities associated with Qinghai-Tibet Plateau uplifting and the variations of uplifting rates rather than paleoclimatic changes.

The reconstruction of sea surface temperature (SST) is a key issue in research on paleoceanography. The recently related studies are mainly concentrated on the Quaternary. The skeletons of a typical species of benthonic foraminifer (Amphistegina radiata) in the top 0–375.30 m interval of Well “Xike-1” reef core, Shidao Island, the Xisha Islands, are uniformly selected. The ratios of magnesium to calcium concentrations and other indicators are analyzed by an electron microprobe analysis (EMPA) with the purpose of estimating the paleo-SSTs since the Pliocene and further investigating the periodic change law of paleoclimate in the South China Sea (SCS). Meanwhile, the geologic significance of paleoclimatic events in the SCS is discussed with global perspectives. The results indicate that the paleo-SSTs reconstructed by the ratios of magnesium to calcium concentrations in the SCS show a general periodic trend of “high–low–high–low” in values changes since the Pliocene. By comparison, the fluctuations of reconstructed paleo-SSTs are much stronger in the Quaternary. Moreover, the variations of the ratios of magnesium to calcium concentrations in the A. radiata skeletons have recorded a series of major paleoclimatic events since the Pliocene, of which the Quaternary glaciation events and the Arctic ice cap forming events during the late Pliocene are more significant. Thus, using the changes of the ratios of magnesium to calcium concentrations in the A. radiata skeletons from Well “Xike-1” reef core to reflect the relative changes of paleo-SSTs is a relatively feasible and reliable way in the SCS, which is also proved by the correlation of drilling cores characteristics in this area.

Different strategies were taken to make virotherapy more effective at killing cancer cells. Among them, oncolytic virus which arms the therapeutic gene to enhance antitumor activity is a prevalent approach. In this study, a newly developed oncolytic vaccinia virus (OVV) that expresses Beclin-1 (OVV-BECN1) was tested for its in vitro and in vivo oncolytic activity in blood cancer. Results showed that the OVV exhibited higher infectivity for leukemia cells. OVV-BECN1 induced significant apoptosis-independent cell death either in wild-type leukemia and multiple myeloma (MM) cell lines or caspase-3 shRNA leukemia cell lines, and had a superior antitumor activity compared to the parent OVV. Autophagic cell death induced by OVV-BECN1 was demonstrated in vitro and in vivo experiments. Finally, upregulation of SIRT-1, a member of class III histone deacetylases, by OVV-BECN1 resulted in the deacetylation of LC3 and its distribution from the nucleus toward the cytoplasm, which might contribute to induction of autophagy. Overall, our data showed a favorable therapeutic effect of the oncolytic vaccinia virus on blood cancers through oncolytic and autophagic mechanisms, and may therefore constitute a promising and effective therapeutic strategy for treating human leukemia and MM. However, further studies are warranted for its reliable clinical translation.

Phenolic foam (PF) has recently been spotlighted because of their excellent flame resistance, low smoke emission, and low production costs. However, PF is mainly prepared from petroleum-based products, and it exhibits poor mechanical strength and high friability. In this study, larch tannin-based rigid phenolic foams (LTPFs) and cork powder was used as filler to prepare cork powder-reinforced LTPFs (CLTPFs). The chemical structure, cell morphology, compressive mechanical properties, friability, thermal properties, and flame retardancy of the foams were evaluated. The results indicated that the LTPFs showed inferior cell morphology, compressive strength and thermal properties, high friability and high flame retardancy as compared with the neat PF. LTPF10 presented the maximal limiting oxygen index (LOI) of 47.8%. As compared with the unreinforced LTPFs, CLTPFs possessed excellent cell morphology, high compressive strength, low thermal conductivity, low friability, and good thermal properties. At a cork powder dosage of 1 wt%, the compressive strength and modulus of CLTPFs increased by 14.84% and 16.18%, respectively; the pulverization ratio and thermal conductivity of CLTPFs decreased by 18.4% and 32.29%, respectively, as compared with those of the LTPF. In addition, the introduction of cork powder improved the thermal stability of LTPFs. The LOI values of the CLTPFs were slightly lower than those of LTPFs. LTPF reinforced with 1 wt% cork powder exhibited the best combination of the features.

This study presents the spatial distribution of total dissolved Cu, Zn, Co, and V during an autumn survey in the East China Sea (ECS). Dissolved Fe and its organic complexation were also investigated. The present study aimed to evaluate the relationship between Cu, Zn, Co, V, D-Fe and its organic ligands and total dissolved phosphate (TDP) in the coastal waters of the ECS. A correlation analysis shows that Cu, Zn and D-Fe were nutrient-like metals, whereas Co and V were non-nutrient-like metals. A multivariate statistical analysis showed that TDP was associated with D-Fe, Cu, Zn and Co, but was not associated with V. Furthermore, TDP was observed to be positively related with D-Fe, while negatively with Fe', which indicated that the limitation of TDP decreased the uptake of Fe'. This paper improves our understanding of the association among trace metals, TDP and phytoplankton biomass in the ECS.

In this paper, we proposed three methods to solve color recognition of Rubik's cube, which includes one offline method and two online methods. Scatter balance & extreme learning machine (SB-ELM), an offline method, is proposed to illustrate the efficiency of training based method. We also put forward a conception of color drifting which indicates offline methods are always ineffectiveness and can not work well in continuous change circumstance. By contrast, weak label hierarchic propagation is proposed for unknown all color information but only utilizes weak label of center block in color recognition. Furthermore, dynamic weight label propagation, another online method, is also proposed for labeling blocks color by known center blocks color of Rubik's cube. We finally design a Rubik's cube robot and construct a dataset to illustrate the efficiency and effectiveness of our online methods and to indicate the ineffectiveness of offline method by color drifting in our dataset.

X-ray flaw detection is a key link in the detection of internal defects in titanium alloy castings which are used for most important components in aeroengines. However, the existing manual defect detection methods from the X-ray images have common drawbacks such as unstable artificial recognition, misdetection, misjudgment, fails of quantitative analysis, huge workload, and low-quality inspection efficiency. To avoid these drawbacks, this paper proposes a new artificial intelligent (AI) method to detect and recognize the aerospace titanium casting defects from the X-ray images. It includes the target defect positioning method named as filtered selective search algorithm (FSS) and the defect classification method named as evenly distributed convolutional neural network (ED-CNN). In the target positioning step, through statistical analysis of defect characteristics, a filtered selective search algorithm is built with two filters (size and edge curvature). In this way, the FSS algorithm can position the defects with almost 100 % of accuracy, hence avoid missed detection and false detection. In the target classification step, an ED-CNN is constructed with a similar structure of the same number of layers in each feature extraction stage, and its entire architecture is evenly distributed. Compared with other three classic high-performance convolutional neural network models (AlexNet, VGG16 and VGG19), the ED-CNN model has the best performance. The ED-CNN model was tested with 324 targets from 50 original images, a classification accuracy of nearly 90 % was obtained for low density holes, porosity, linear defects, high density inclusions and casting structure. The FSS/ED-CNN method of two phases defect detection proposed in this paper can achieve accurate positioning and high accurate classification of typical defect targets, and is expected to solve the common drawbacks of "manual defect detection". The newly-proposed FSS/ED-CNN method has important research significance and engineering value.

Condensed tannins from larch bark extracts are a natural renewable and eco-friendly material and are potential substitutes for phenolic petrochemicals. However, the wide application of tannin is restricted by its low reactivity. Therefore, the goal of this study was to enhance the reactivity of larch tannin by depolymerization and determine optimal reaction conditions. The structures of larch tannin and depolymerized larch tannin were characterized by Fourier transform infrared (FT-IR) spectroscopy, solid phase 13C-NMR and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The thermal stability of larch tannin before and after depolymerization was evaluated by thermogravimetric analysis (TGA). The results indicated that the monomeric units of larch tannin were mainly composed of catechin/epicatechin, gallocatechin/epigallocatechin, catechin–gallocatechin esters, and stilbene glucosides. The presence of a catechin gallate dimer that had lost both gallic acid residues and a hydroxy group and a small amount of fisetinidin units were also observed. Additionally, a series of peaks corresponding to oligomers of larch tannin of up to 11 repeating units were observed from the MALDI-TOF MS data. Depolymerization treatment, especially using 2-mercaptoethanol as a nucleophilic reagent, was found to be beneficial to the enhancement of thermal stability. The optimization of the depolymerization reaction allowed the reaction to be completed in two hours, at 60 °C, using 2-mercaptoethanol as a nucleophile and 0.1 mol L−1 HCl. Many compounds of molecular weight less than 600 Da, mainly dimers and monomers, were obtained under these reaction conditions.

Precious wood has high performances, but has limited availability, increasingly rising cost, and requires a long growth cycle. Imitation precious wood was prepared from low-cost and fast-growing poplar wood using the method of wood polymer composites (WPCs). Poplar wood was impregnated with phenol formaldehyde (PF) resins in the presence of surfactants as osmotic agents to achieve efficient PF permeability. The effects of formaldehyde/phenol (F/P) molar ratio, surfactant type, and surfactant amount on the performances of PF resins and the modified woods were investigated in detail. The wetting process of PF resins on wood surface and its molecular weight distribution were observed by contact angle measurement and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), respectively. The physical and mechanical properties of the resultant WPCs were also evaluated. The poplar wood treated with PF-DTAB-0.8% resin (F/P = 1.6) exhibited lower viscosity (23.9 mPa s), lower molecular distribution and better permeability. The weight percent gains (WPG) of the treated material reached 104.82%, and its hardness reached 66.86 shore D. overall, this approach has the potential to make a wood product that can partially substitute for precious wood. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

In this study, a simple method for the simultaneous determination of trace metals (Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry (ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L−1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.

Provenances of pelagic sediments are a less well-known and key problem of sedimentation in the deep sea. Two sediment cores from the south and middle Shikoku Basin are selected for grain size analysis and element geochemical analysis in this paper. Grain size analysis for the studied cores shows that the grain sizes become coarser upwards gradually, especially for subsurface sediments. It probably reveals the enhancement of terrigenous clastic material. Rare elements analysis reveals that two cores are enriched in Ba and Th. However, the other elements are more or less the same as those of the North American Shales (NAS). Through the NASC-normalized REE distribution, curves are nearly aclinic, and there are no Ce and Eu anomalies. The geochemical characteristics of elements indicate that the sediments in the Shikoku Basin should mainly be regarded as hemipelagic and pelagic sediments. The comparison of samples from the Nankai Trough, Kyushu Ridge and Izu Island Arc and the analysis of DSDP and ODP cores jointly show that the sediments of the core SG1-2 have an apparent ‘affinity’ with the Nankai Trough. The core SG1-1 is influenced by the submarine volcanic activities, having a relatively complex provenance, and is possibly derived from the spreading centre of the Kyushu Ridge and the central Shikoku Basin. Copyright © 2016 John Wiley & Sons, Ltd.

In order to discuss the content distributions and fluxes of heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang (Yangtze) Estuary, the contents of heavy metals (Zn, Pb, Cd, Co and Ni) have been analyzed. During a tidal cycle, the average contents of heavy metals are in the order of Zn>Ni>Pb>Co≫Cd. The average contents in ebb tide are generally higher than that in flood tide. However, at the inshore Sta. 11, influenced by the contamination from the nearby waste treatment plant, the average contents of Zn and Ni in flood tide are higher than those in ebb tide and at the offshore Sta. 10, the content of Cd in flood tide higher than that in ebb tide due to marine-derived materials. The five heavy metals, mainly terrigenous, are transported towards east-northeast, and settle down with suspended matters in the area between Sta. 11 and Sta. 10. Influenced by marine-derived materials, the flux value of Cd does not alter significantly with obviously changing in flux direction towards northwest. The source of heavy metals, the salinity of water and the concentration of suspended matters are the main factors controlling the content distributions of heavy metals during a tidal cycle. There is a positive correlation between the contents of heavy metals (Zn, Pb, Co and Ni) and the salinity of water, while the opposite correlation between the contents and the concentrations of suspended matters. Because of marine-derived materials, the content of Cd is not correlated with the concentration of suspended matters and the salinity of water.

The distribution of total dissolved iron and organic ligands in the coastal waters of the East China Sea, especially in the Yangtze River estuary, was investigated using competitive ligand equilibration–adsorptive cathodic stripping voltammetry (CLE–ACSV) with 2,3-dihydroxynaphthalene (DHN) as the competing ligand. The seasonal variation of total dissolved iron (D-Fe) and its organic ligands (Lt) were observed in spring and autumn. The average D-Fe concentration in both surface and bottom waters in spring was higher than that in autumn. With respect to the horizontal distribution of D-Fe and Lt content, the highest values were observed in the estuary stations located in the Yangtze River Estuary and the Hangzhou Bay area and the lowest values were observed in offshore stations. The average surface D-Fe concentration of estuary stations in spring and autumn was 39.4 ± 26.6 (the standard deviation) nmol/L and 20.5 ± 11.0 nmol/L, respectively. The average bottom D-Fe concentrations of estuary stations in spring and autumn were 76.1 ± 58.6 nmol/L and 78.5 ± 39.0 nmol/L, respectively. Higher surface Lt concentrations were observed during the spring. The average surface Lt concentrations of estuary stations in spring and autumn were 40.0 ± 26.8 and 23.2 ± 7.8 nmol/L, respectively. The concentration of D-Fe and Lt in the bottom water was higher than that observed in surface water and exhibited less seasonal variability. Strong ligands were observed in spring estuary surface water. The average surface logK'FeL values in spring and autumn were 12.9 ± 0.8 and 11.7 ± 0.5, respectively. The total ligand concentration in this study was generally in excess of the dissolved iron, particularly in autumn at offshore stations. Higher excess organic ligand concentrations were also generally observed in the upper water column compared to bottom waters in autumn.

Substitution of one of the phenyl groups of triphenylphosphine with a 2-benzyloxy-, 2-benzyloxymethyl- or 2-benzyloxyethyl-phenyl moiety results in a set of simple ligands, which exhibit strikingly different behaviour in various nickel(II)-catalyzed olefin dimerization reactions. Complexes of ligands with 2-benzyloxyphenyl-, 2-benzyloxymethylphenyl-diphenylphosphine (L5 and L6 respectively) are most active for hydrovinylation (HV) of vinylarenes, with the former leading to extensive isomerization of the primary 3-aryl-1-butenes into the conjugated 2-aryl-2-butenes even at −55 °C. However, 2-benzyloxymethyl-substituted ligand L6 is slightly less active, leading up to quantitative yields of the primary products of HV at ambient temperature with no trace of isomerization, thus providing the best option for a practical synthesis of these compounds. In sharp contrast, hydrovinylation of a variety of 1,3-dienes is best catalyzed by nickel(II)-complexes of 2-benzyloxyphenyldiphenylphosphine, L5. The other two ligands, 2-benzyloxymethyl-(L6) and 2-benzyloxyethyl-diphenylphosphine (L7) are much less effective in the HV of 1,3-dienes. Nickel(II)-catalyzed cycloisomerization of 1,6-dienes into methylenecyclopentanes, a reaction mechanistically related to the other hydrovinylation reactions, is also uniquely effected by nickel(II)-complexes of L5, but not of L6 or L7. In an attempt to prepare authentic samples of the methylencyclohexane products, nickel(II)-complexes of N-heterocyclic carbene-ligands were examined. In sharp contrast to the phosphines, which give the methylenecyclopentanes, methylenecyclohexanes are the major products in the (N-heterocyclic carbene)nickel(II)-mediated reactions.

Non-tumorous liver tissue removed during surgery to resect hepatocellular carcinoma (HCC) is potentially a useful source of material from which cells, particularly liver progenitor/stem cells (LPCs), can be isolated to establish cell lines. The purpose of this study was to evaluate the applicability of the "plate-and-wait" method to derive LPCs from resections to remove HCC. Three independent non-tumorous liver samples from HCC resection and 3 samples from liver donors were used for LPC isolation. Staining for LPC markers, OV6, CK19, and EpCAM, in the above liver samples demonstrated staining in only 2 of the non-tumorous samples. We isolated 2 human liver epithelial cell lines (HLECs) from these 2 samples. These HLECs were positive for general stem cell markers CD133, EpCAM, and Oct4. They expressed the liver progenitor cell markers OV6, CK14, and M2PK but not CK19. They also expressed the hepatocellular markers albumin, CK8, CK18, HNF4-alpha, and the drug-metabolizing gene CYP3A4. These cells accumulated glycogen, indocyanine green, and synthesized urea. They produced colonies in soft agar that showed anchorage-independent growth and their tumorigenic status was confirmed when they produced tumors following transfer to athymic nude mice. In contrast, the third non-tumorous tissue and 3 normal liver samples did not produce cell lines. This study establishes a correlation between the presence of LPCs in the source liver tissue and the ability to derive cell lines from these tissues. The phenotypic similarities between the LPCs and the HLECs suggest that a precursor-product relationship may exist between the 2 cell types.

α-Alkylstyrenes undergo efficient hydrovinylation (addition of ethene) in the presence of a nickel catalyst prepared from [(ally])NiBr] 2 , Na + [BAr 4 ] ― [Ar = 3,5-bis(trifluoromethyl)phenyl], and a phosphoramidite ligand giving products in excellent yields and enantioselectivities. In many cases phosphoramidites derived from achiral 2,2'-biphenol are almost as good as ligands derived from the more expensive enantiopure 1,1'-bi(2-naphthol)s. The hydrovinylation products, which carry two versatile latent functionalities, an aryl and a vinyl group, are potentially useful for the synthesis of several important natural products containing benzylic all-carbon quaternary centers.

The grain size and element (including redox sensitive elements and terrigenous elements) concentration of surface sediments from the Changjiang Estuary hypoxia zone and its adjacent sea area were measured in this research. Based on the obtained data, the hypoxic environment’s influence on the distribution of elements in surface sediments was further studied. We believe that the “redox environment effect” greatly influences the distribution of the RSE, which reveals the “patchy enrichment pattern” offshore in the hypoxia zone, while the distribution of the terrigenous elements which shows the “stripped enrichment pattern” near shore is mainly affected by “granularity effects”. Due to the existence of the hypoxia zone of the Changjiang Estuary, the distribution of the RSE such as Mo, Cd and V in the study area exhibits the characteristics of “redox environment effects”.

The bivalve Ruditapes philippinarum is not only one of the main molluse species in the west Pacific Ocean, but also one of the main species for aquaculture in China. Knowledge of growth of the R. philippinarum shell will improve our understanding of the shell as an environmental archive. It is also useful for the aquaculture of R. philippinarum. In this research, a hanging box culture method was introduced in the culture of R. philippinarum. The bivalves were cultured for 126 days, from March 31 to August 3, 2002. The average growth rates of shell width, height, and thickness were 0.069, 0.046, and 0.032 mm/d, respectively. The mean increase of average individual wet mass was 0.028 g/d. The largest growth rates of both shell and average individual wet mass occurred in June, indicating that water temperature and bivalve reproduction were 2 important factors. The shell morphology underwent significant changes with shell growth. The ratio of height to thickness (value of B/C) shifted 1.58 in the first 60 days to 1.54 in the last 30 days, which was resulted from the change in major shell growth direction. Periodic changes in the B/C ratio led to corrugated shell form, which could be used to determine the age of the shell.

The heavy metals (Cu, Co, Ni, Zn, Cr, Pb, Cd) in surface and core sediments from the central Bohai Sea were analyzed to evaluate the temporal/spatial distribution and pollution status. Cd exhibited gradual increase vertically, while others were stable or declined slightly in core sediments. In surface sediments, metals showed higher values in 'central mud area of the Bohai Sea' and the coastal area of the Bohai Bay. Cd and Pb also had high levels in the northeastern part of Bohai Sea. Both the contamination factors (CFs) and the geo-accumulation index (Igeo) indicated that Cu, Co, Ni, and Cr were not at pollution levels, while Pb, Zn, and Cd indicated moderate contamination. Compared with sediment quality guidelines (SQGs), Cu, Zn, Cr, Pb, and Cd were likely to produce occasional adverse biological effects, while Ni showed possible ecotoxicological risks. The combined levels of the metals have a 21% probability of being toxic.

Two different types of coupling patterns for the Pd(0)-catalyzed coupling reaction of allenic/propargylic zinc reagents with organic halides or propargylic carbonates (acetate) with the corresponding organometallic reagents were observed. After studying the controlling factors on the regioselectivity of this reaction, we demonstrated that the steric hindrance of both reactants and the types of organic halides determine the regioselectivity of this coupling reaction. By subtle choosing of the substrates, the regioselectivity can be tuned. On the basis of these results, new methodologies for the highly regio- and stereoselective synthesis of 6-substituted hex-5-yn-2-enoates and 4,6-dialkylhexa-2,4,5-trienoates have been developed. Some of the products synthesized by the carbonate protocol cannot be prepared by the lithiation protocol because the regioselectivity of lithiation of dialkyl-substituted internal alkynes is an intrinsic problem.

Substitution of one of the phenyl groups of triphenylphosphine with a 2-benzyloxy-, 2-benzyloxymethyl- or 2-benzyloxyethyl-phenyl moiety results in a set of simple ligands, which exhibit strikingly different behaviour in various nickel(II)-catalyzed olefin dimerization reactions. Complexes of ligands with 2-benzyloxyphenyl-, 2-benzyloxymethylphenyl-diphenylphosphine (L5 and L6 respectively) are most active for hydrovinylation (HV) of vinylarenes, with the former leading to extensive isomerization of the primary 3-aryl-1-butenes into the conjugated 2-aryl-2-butenes even at -55 °C. However, 2-benzyloxymethyl-substituted ligand L6 is slightly less active, leading up to quantitative yields of the primary products of HV at ambient temperature with no trace of isomerization, thus providing the best option for a practical synthesis of these compounds. In sharp contrast, hydrovinylation of a variety of 1,3-dienes is best catalyzed by nickel(II)-complexes of 2-benzyloxyphenyldiphenylphosphine, L5. The other two ligands, 2-benzyloxymethyl-(L6) and 2-benzyloxyethyl-diphenylphosphine (L7) are much less effective in the HV of 1,3-dienes. Nickel(II)-catalyzed cycloisomerization of 1,6-dienes into methylenecyclopentanes, a reaction mechanistically related to the other hydrovinylation reactions, is also uniquely effected by nickel(II)-complexes of L5, but not of L6 or L7. In an attempt to prepare authentic samples of the methylencyclohexane products, nickel(II)-complexes of N-heterocyclic carbene-ligands were examined. In sharp contrast to the phosphines, which give the methylenecyclopentanes, methylenecyclohexanes are the major products in the (N-heterocyclic carbene)nickel(II)-mediated reactions.

The Pd(0)-catalyzed coupling reaction of electron-deficient alkenyl halides with the organozinc formed by the subsequent treatment of 1-phenylalk-1-yne with n-BuLi and ZnBr2 with or without a catalytic amount of HgCl2 was studied. Both the allene-formation- and the alkyne-formation-type coupling reactions were observed with high regio- and stereoselectivity: the reaction of 1-phenylprop-1-yne afforded 6-phenylhex-5-yn-2(or 3)-enoates and -enitriles, while the reaction of 1-phenylhex-1-yne formed 4-phenyl-6-substituted-hexa-2,4,5-trienoates. A plausible explanation for the regioselectivity was discussed. The double bonds in 6-phenylhex-5-yn- 2-enoates were prone to migrate to the position conjugated with the carbon-carbon triple bonds to form 6-phenylhex-5-yn-3-enoates at higher temperature. The migration did not occur in absence of an excess amount of allenic/propargylic zinc reagent or at low temperature.

The Pd(0)-catalyzed coupling reaction of electron-deficient alkenyl halides with the organozinc formed by the subsequent treatment of 1-phenylalk-1-yne with n-BuLi and ZnBr2 with or without a catalytic amount of HgCl2 was studied. Both the allene-formation- and the alkyne-formation-type coupling reactions were observed with high regio- and stereoselectivity: the reaction of 1-phenylprop-1-yne afforded 6-phenylhex-5-yn-2(or 3)-enoates and -enitriles, while the reaction of 1-phenylhex-1-yne formed 4-phenyl-6-substituted-hexa-2,4,5-trienoates. A plausible explanation for the regioselectivity was discussed. The double bonds in 6-phenylhex-5-yn-2-enoates were prone to migrate to the position conjugated with the carbon−carbon triple bonds to form 6-phenylhex-5-yn-3-enoates at higher temperature. The migration did not occur in absence of an excess amount of allenic/propargylic zinc reagent or at low temperature.

α-Alkylstyrenes undergo efficient hydrovinylation (addition of ethene) in the presence of a nickel catalyst prepared from [(ally])NiBr] 2 , Na + [BAr 4 ] ― [Ar = 3,5-bis(trifluoromethyl)phenyl], and a phosphoramidite ligand giving products in excellent yields and enantioselectivities. In many cases phosphoramidites derived from achiral 2,2'-biphenol are almost as good as ligands derived from the more expensive enantiopure 1,1'-bi(2-naphthol)s. The hydrovinylation products, which carry two versatile latent functionalities, an aryl and a vinyl group, are potentially useful for the synthesis of several important natural products containing benzylic all-carbon quaternary centers.

Cyclic and acyclic 1,3-dienes undergo efficient (substrate/catalyst = 72) heterodimerization with ethylene in the presence of a Ni catalyst prepared from [o-(PhCH2O)]C6H4PPh2, [(allyl)2NiBr]2, and Na+ BAr4- (Ar = 3,5-bis-trifluromethylphenyl), giving 1,2-addition products. Yields up to 99% can be realized for several 1-vinylcycloalkenes and 1-substituted 1,3-butadienes. Phospholanes with suitably placed hemilabile ligating groups and phosphoramidites derived from binaphthol are excellent ligands for an asymmetric variation of this reaction, the latter giving 99% yield and >95% ee's for selected substrates. An example of how an exocyclic chiral center can be used to install other stereo-centers in the ring (e. g., the carbon to which the side chain is attached) is also provided. These discoveries open an expeditious entry into several biologically relevant classes of compounds, especially those carrying tetrahydronaphthalene and related heterocyclic moieties.

[reaction; see text] Aza-enediynes (C,N-dialkynyl imines) undergo thermal aza-Bergman rearrangement to beta-alkynyl acrylonitriles through 2,5-didehydropyridine (2,5-ddp) intermediates. Certain aza-enediynes also undergo an alternative process affording enediynes and fumaronitriles. Studies employing a specifically (l3)C-labeled aza-enediyne show that the conversion to enediyne is second order in aza-enediyne, proceeds by a "head-to-tail" coupling, and affords the (Z)-enediyne.

[reaction: see text] A three-step, two-pot procedure involving asymmetric hydrovinylation followed by Suzuki-Miyaura reaction represents by far the shortest synthesis of this popular bisabolane. Other applications for the synthesis of similar compounds with chiral benzyl centers can be easily envisioned.

Benzophenone Iodine 3,5-Bis(trifluoromethyl)bromobenzene Sodium tetrafluoroborate Bis[1,2:5,6-eta-(1,5-cycloocatadiene)nickel Allyl bromide Ethylene n-Butyllithium Methyltriphenylphosphonium bromide Triphenylphsophine oxide Sodium tetrakis[(3,5-trifluoromethyl)phenyl]borate Di-(mu-bromo)bis(eta-allyl)nickel(II) 2-Phenyl-1-butene (R)-3-Methyl-3-phenylpentene Keywords: hydrovinylation; 2-phenyl-1-butene; nickel catalyst; 3-arylbutenes; 2-arylpropionic acids; lignads; asymmetric reaction; vinylarenes; waste disposal