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The Wnt pathway is essential for the initiation of lizard tail regeneration. The regenerated lizard tails exhibit obvious morphological differences compared to the original ones. The expression of Wnt1 and Wnt2b proteins in the regenerating tail of Scincella tsinlingensis was detected by immunohistochemistry and then comparatively analyzed for ultrastructural changes in the original and regenerated spinal cord. The ependymal layer of the original spinal cord was pseudostratified with multiciliated cells and primary monociliated cells, while the cells of the ependymal layer of the regenerated spinal cord were organized in a monolayer with a few biciliated cells. Immunolocalization indicated that Wnt1 and Wnt2b were mainly distributed in the dermis near the original tail stump, spinal cord, and clot-positive migratory cells during Stage I, 0-1 days post-amputation (dpa). Wnt1 and Wnt2b were predominantly detected in the epaxial and hypaxial musculature near the original tail stump, wound epithelium, and spinal cord in the original tail during Stage II, 1-7 dpa. Mesenchymal cells and wound epithelium showed immunostaining during Stage III and IV, 7-15 dpa. The ependymal tubes contained these signaling proteins during Stage V and VI, 20-30 dpa. Labeling was mainly observed in nearby regenerative blood vessels, ependymal cells, epaxial and hypaxial musculature in the apical epithelial layer (AEC) after 45-160 dpa. These findings indicated that Wnt1 and Wnt2b proteins presented primarily in regenerating epidermis and nerve tissues were a critical signal for tail regeneration in S. tsinlingensis. [ABSTRACT FROM AUTHOR]

Biomass energy is one of the most accessible and readily available carbon-neutral energy options as a RES. It is regarded as a viable alternative fuel for coal combustion, particularly for biomass co-firing with pulverized coal, with numerous applications. The CFD can provide reasonably accurate solutions to complex thermo-chemical-fluid interactions, which is useful for understanding the design or retrofit of boilers and can save time, money, and effort. In this study, a CFD simulation of a 300 MW pulverized coal boiler with biomass co-firing was performed to investigate the impact of biomass co-firing with coal, considering the biomass co-firing ratio, mixing effect, and feeding temperature. The results show that the flow field in the furnace does not change significantly under different biomass blending ratio. Biomass co-firing can reduce peak temperatures in the furnace and make the temperature distribution more uniform. The concentration of unburned carbon in the furnace decreases as the biomass blending ratio increases. Furthermore, biomass blending has a significant impact on nitrogen oxide reduction, with NOx emissions reduced by 20% and 28%, respectively, when the biomass blending ratio is 15% and 30%. The change of parameters inside the furnace caused by the reduction of biomass powder feeding temperature about 80 K is not significant. On the other hand, co-firing biomass with coal, reduces the risk of biomass spontaneous combustion while maintaining the furnace combustion stability and boiler combustion efficiency. The optimum ratio of biomass co-firing ration is deduced in this study is up to 20%. [ABSTRACT FROM AUTHOR]

Herein, we present a new method for preparing homoligand 3D coordination polymers. First, a layered metal-organic framework Zn3(BDC)3(H2O)2·4DMF 1 (BDC is terephthalate, DMF is N,N-dimethylformamide) was fabricated from a H2BDC by liquid-liquid diffusion. Second, the layered product, 1, was used as a precursor to solvothermally react with further H2BDC at 140-180 °C, resulting in two products of BDC insertion into the layered structure. These are [Zn3(p-BDC)4]·2HPIP, 2 (HPIP is partly protonated piperazine), and [Zn3(p-BDC)3(H2BDC)]·(C6H15NO)·H2O·3DMF, 3 (C6H15NO is triethylamine N-oxide). Single-crystal X-ray diffraction shows that 2 possesses a layer- pillared structure of μ2-BDC, with 1D channels, while 3 has a layer-pillared structure of μ2-BDC, with 2D channels. N2-sorption experiments show 3 has a relatively high BET surface area of 750 m²/g. It is proposed that 2 follows the crystal growth mechanism of Ostwald ripening, whereas the crystal structure of 3 might be formed by an insertion mechanism. [ABSTRACT FROM AUTHOR]

Given the central importance of protected area systems in local, regional and global conservation strategies, it is vital that there is a good understanding of their effectiveness in maintaining ecological functioning. Here, we provide, to our knowledge, the first such global analysis, focusing on plant production, a ''supporting'' ecosystem function necessary for multiple other ecosystem services. We use data on the normalized difference vegetation index (NDVI) as a measure of variation in plant production in the core, boundary and surroundings of more than 1000 large protected areas over a 25 year period. Forested protected areas were higher (or similar), and those non-forested were lower (or similar), in NDVI than their surrounding areas, and these differences have been sustained. The differences from surrounding areas have increased for evergreen broadleaf forests and barren grounds, decreased for grasslands, and remained similar for deciduous forests, woodlands, and shrublands, reflecting different pressures on those surroundings. These results are consistent with protected areas being effective both in the representation and maintenance of plant production. However, widespread overall increases in NDVI during the study period suggest that plant production within the core of non-forested protected areas has become higher than it was in the surroundings of those areas in 1982, highlighting that whilst the distinctiveness of protected areas from their surroundings has persisted the nature of that difference has changed. [ABSTRACT FROM AUTHOR]

In this paper, crystal growth of calcium carbonate CaCO3 in the presence of biomolecules of lotus root was investigated. Scanning electron microscopy, Fourier transform infrared spectroscopy and Xray powder diffractometry were used to characterize the products. The results indicate that calcite spherical particles were constructed from small rhombohedral subunits. Similar CaCO3crystals were also gained when crystal growth of CaCO3in aqueous solution containing extracts of lotus root was performed, suggesting that the soluble biomolecules of lotus root play a crucial role in directing the formation of hierarchical calcite spherical particles. The possible formation mechanism of the CaCO3crystals by using lotus root is also discussed, which can be interpreted by particleaggregation based nonclassical crystallization laws. The biomolecules of lotus root might induce and control the nucleation and growth of calcium carbonate crystals. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]

An original low-temperature solid-state route for the preparation of metal β-diketonates in their unsolvated forms has been suggested. Four new first row divalent transition metal β-diketonates, M(hfac)[sub2] (M = Mn (1), Fe (2), Co (3), and Ni (4); hfac = hexaluoroacetylacetonate), have been isolated in quantitative yield. Compounds 1-3 have been obtained by comproportionation reaction between the corresponding M(hfac)3 and metal powder. Ni(hfac)[sub2] (4) has been synthesized by oxidation of metallic nickel with Cu(hfac)[sub2]. All products have been characterized spectroscopically and by X-ray powder and single crystal diffraction techniques. The solid state structures of 1-4 feature polynuclear molecules, in which the coordinatively unsaturated metal centers fulfill an octahedral environment by Lewis acid-base interactions with the oxygen atoms of diketonate ligands acting in chelating-bridging fashion. Title transition metal diketonates have been shown to retain their polynuclear structures upon sublimation-deposition procedure as well as in solutions of non-coordinating solvents. In coordinating solvents the molecules of 1-4 quickly form the mononuclear M(hfac)[sub2]L[sub2] (L = donor solvent) complexes. [ABSTRACT FROM AUTHOR]

Objective: This study determined whether the effect of combination therapy for hepatic carcinoma (HCC) is comparable to surgical resection (SR). According to the guidelines of the American Association for the Study of Liver Disease, radiofrequency ablation (RFA) and SR are recommended for early HCC. However, patients treated with RFA had worse long‑term survival than those who received SR. Many studies utilizing the combination therapy with RFA and transarterial chemoembolization (TACE) have reported better prognosis as compared to RFA alone. Materials and Methods: A comprehensive search in databases was conducted. Six retrospective studies and one cohort were enrolled in this meta‑analysis. The overall survival (OS), disease‑free survival (DFS), and major complications were compared between RFA plus TACE and SR. The pooled hazard ratio and 95% confidence interval (CI) were calculated and analyzed. Results: After comparison, no significant difference in the OS and DFS at 1 and 3 years between the combination therapy and SR was observed (OS1: pooled relative risk [RR]: 0.82, 95% CI [0.56, 1.21]; OS3: pooled RR: 1.07, 95% CI [0.82, 1.39]; DFS1: pooled RR: 0.92, 95% CI [0.58, 1.45]; DFS3: pooled RR: 1.18, 95% CI [1.00, 1.40]). SR had better clinical outcomes than combination therapy with respect to long‑term survival and disease progression (OS5: pooled RR: 1.12, 95% CI [1.03, 1.23]; DFS5: pooled RR: 1.15, 95% CI [1.03, 1.28]). Major complications were reduced with combination therapy (pooled RR: 0.46, 95% CI [0.25, 0.85]). Conclusion: SR should remain as the first‑line therapy for early HCC. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks with tunable functional groups like solid-solution have received considerable interest. In this paper, a crs-type structure built of [Zn3(OH)(dmtrz)3] triazolate-trinuclear and [Zn2(COO)4] paddlewheel units, linked by 3,5-dimethyl-1,2,4-triazolate (dmtrz) and isophthalate (ipa) ligands (named as MAC-4-A), has been used as a prototype framework. Four types of functional groups (B: 5-hydroxyisophthalate, C: 5-aminoisophthalate, D: 5-ethoxyisophthalate, and E: 5-acetamidoisophthalate) have been integrated into the framework, giving isostructures of MAC-4-B to E, respectively. Then, by the solid-solution framework approach, four group samples are prepared, which are MAC-4-AB-x, MAC-4-AC-x, MAC-4-AD-x, and MAC-4-AE-x (x denoted as the ratio of functional ligands in the framework, x = 0.3, 0.5, 0.7), and their CO2 and N2 adsorptions have been studied. Our results revealed that the CO2 capacity is enhanced with the increase of functional groups and then decreases, showing a maximum uptake amount on MAC-4-AB-0.5, MAC-4-AC-0.5, MAC-4-AD-0.7, and MAC-4-AE-0.5 at 298 K and 1 bar, respectively. On the other hand, the calculated selectivity of CO2 over N2 gradually increases, giving the highest selectivity after the pore surface is completely functionalized. [ABSTRACT FROM AUTHOR]

Risk management is of great significance and extremely difficulty in important scientific and technological equipment development projects. The complexity and risk of important scientific and technological equipment development projects are deeply researched in this paper. On the basis of milestone event tree and a game containing profit complementary between risk elements and project subjects, a game house and its decomposed models are established. Additionally, the risk index measurement model is developed with the consideration of the mapping between the risk index and the game profit of both participants in the game. Moreover, a risk genealogy and a high-risk diagram are constructed, which is able to be employed to indentify high-risk. [ABSTRACT FROM AUTHOR]

The first fluorescent probe for mammalian thioredoxin reductase (TrxR), TRFS-green, was designed, synthesized, and fully evaluated. The probe features a 1,2-dithiolane scaffold with a quenched naphthalimide fluorophore. TRFS-green displays a green fluorescence off-on change induced by the TrxR-mediated disulfide cleavage and subsequent intramolecular cyclization to liberate the masked naphthalimide fluorophore. It was demonstrated in vitro that TRFS-green manifests high selectivity toward TrxR over other related enzymes and various small molecule thiols as well as biological reducing molecules. HPLC analyses indicated that TRFS-green was exclusively converted to naphthalimide catalyzed by TrxR. The ability in triggering on the fluorescence signal by cellular protein extracts correlates well with the endogenous TrxR activity in different cells. Furthermore, inhibition of TrxR by 2,4-dinitrochlorobenzene or depletion of TrxR by immunoprecipitation remarkably decreases the reduction of TRFS-green by cellular protein extracts. Finally, TRFS-green was successfully applied in imaging TrxR activity in living cells. The fluorescence signal of TRFS-green in living cells was inhibited by pretreating the cells with TrxR inhibitor in a dose-dependent manner, potentiating the development of living cell-based screening assay for identifying TrxR inhibitors. We expect the novel fluorescent probe TRFS-green would facilitate the discovery of TrxR-targeting small molecules for potential therapeutic agents and provide significant advances in understanding the physiological/pathophysiological functions of TrxR in vivo. [ABSTRACT FROM AUTHOR]

Seven new metal–organic frameworks (MOFs) have been synthesized using different organic amines as templates: [Cd(HBTC) 2]·2(HDETA)·4(H 2O) ( 1) (BTC = 1,3,5-benzenetricarboxylate and DETA = diethylenetriamine), [Cd 2(BTC) 2(H 2O) 2]·2(HCHA)·2(EtOH)·2(H 2O) (CHA = cyclohexylamine) ( 2), [Cd 5(BTC) 4Cl 4]·4(HTEA)·2(H 3O) (TEA = triethylamine) ( 3), [Cd 3(BTC) 3(H 2O)]·(HTEA)·2(H 3O) ( 4), [Zn(BTC)(H 2O)]·(HTPA)·(H 2O) (TPA = tri- n-propylamine) ( 5), [Cd(BTC)]·(HTPA)·(H 2O) ( 6), and [Cd 2(BTC)(HBTC)]·(HTBA)·(H 2O) (TBA = tri- n-butylamine) ( 7). Topologically, the polymer 1exhibits a two-dimensional (2D) Cd-HBTC network with (4 4) topology, which is a sql structure; the polymer 2possesses a three-dimensional (3D) porous Cd-BTC framework with (4·6 2) 2(4 2·6 10·8 3) topology, which is a contorted rutile structure; polymer 3exhibits a 3D open Cd-BTC architecture with (6 2·8 2·10 2) 2(6 2·8 4)(6 3) 4topology; polymer 4is a 3D porous Cd-BTC network with new (4·6 2) 2(4 2·6 4·8 6·10 3)(6·8 2) 2(6 2·8 4)(6 2·8 4) 2(6 2·8) 2topology; similar to 1, polymer 5is a 2D Zn-BTC framework with (4·8 2) topology; interestingly, polymer 6possesses a 3D porous Cd-BTC architecture with the same topology as 2; polymer 7shows a 3D open Cd-BTC framework with (6 3)(6 5·10) topology. In addition to the structures of polymers 1– 7, their thermal stabilities, ion exchange properties, and nonbonding interaction energies, including H-bonding and van der Waals, have also been studied. Remarkably, those organic amine cations reside in the interlayer or channel space, playing important roles such as templating, space-filling, and charge-balancing agents. These studies would facilitate the exploration of novel MOFs with charming molecular topologies and multifunctional properties. [ABSTRACT FROM AUTHOR]

Two 3D chiral multifunctional microporous MOFs, Zn3(BTC)2(DMF)3(H2O)·(DMF)(H2O) (1) and Cd4(BTC)3(DMF)2(H2O)2·6(H2O) (2) (H3BTC = 1,3,5-benzenetricarboxylic acid and DMF = N,N′-dimethylformamide), have been synthesized in the presence of organic bases tributylamine (TBA) and triethylamine (TEA), respectively. 1 (C30H38N4O18Zn3) crystallizes in the tetragonal P41212 space group (a = 13.6929(19) Å, c = 50.664(10) Å, V = 9499(3) ų, and Z = 8). 2 (C33H39N2O28Cd4) crystallizes in the tetragonal P4322 space group (a = 10.3503(4) Å, c = 52.557(3) Å, V = 5630.4(4) ų, and Z = 4). X-ray crystallography reveals that 1 consists of a 3D open framework with the (6³)4(6²·8²·10²)(6·48²)2 topology, but 2 exhibits a 3D open network with the (4²·5)2(4·45·106·87·48²) topology. The solid-state excitation-emission spectra show that the strongest excitation peaks for 1 and 2 are at 341 and 319 nm, and their emission spectra mainly show strong peaks at 410 and 405 nm, respectively. The amounts adsorbed of 1 (2) are 169 mg/g (126 mg/g) for H2O, 137 mg/g (102 mg/g) for C2H5OH, and 133 mg/g (99 mg/g) for CH3OH, which are equivalent to the adsorption of about 62 (34) H2O, 20 (11) C2H5OH, and 28 (16) CH3OH per unit cell, respectively. [ABSTRACT FROM AUTHOR]