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A flexible octadentate C-shaped bis(salamo)-based ligand (H4L) with two different coordination environments, which can react with different metal salts to form heterotrinuclear zinc(II)-lanthanide(III) bis(salamo)-based complexes [Zn2La(L)(µ2-OAc)2(η2-NO3)]·2CH2Cl2 (1) and [Zn2Ce(L)(µ2-OAc)2(η2-NO3)] (2). The detailed analysis of Hirshfeld surfaces and fingerprints compares the intermolecular interactions, which are very important for the construction of different supramolecular structures. The molecules are connected by the combination of C–H···O hydrogen bonds to form an infinite 1D supramolecular chain. [ABSTRACT FROM AUTHOR]

A homo-dinuclear Cu(II) complex [Cu2(L)2] with the stoichiometric ratio of Cu(II) : (L)2– = 2 : 2 was synthesized by the reaction of the ligand (4-methyl-6-aldehyde-6′-methoxy-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol) with Cu(OAc)2·H2O in the mixed CH2Cl2–MeOMe–EtOH solution (an unexpected ligand is the intermediate of condensation reaction of starting ligand with acetone). The Cu(II) complex was characterized by elemental analysis, IR, UV-Vis and X-ray crystallography. The Cu(II) complex crystallizes in monoclinic space group P21/n and consists of two Cu(II) atoms and two completely deprotonated ligand (L)2– units. Through the analysis of intermolecular interactions, the Cu(II) complex units can form a 2D supramolecular structure through intermolecular hydrogen bonds and C–H···π interactions, respectively, meanwhile, the molecular interactions were quantitatively studied by Hirshfeld surfaces analyses. The fluorescence properties and DFT calculations were performed. [ABSTRACT FROM AUTHOR]

The aim of this research was to develop an experimental–numerical approach to characterize the effect of constant loading coupled with elevated temperature on epoxy bulk adhesive and to predict the stress degradation of bulk adhesive specimen under 15% and 25% tensile failure loads for the automotive industry. A power-law creep model was built to simulate the effect of temperature and loading on adhesive mechanical behavior, and the related strength degradation simulation has also been implemented using a creep strain-dependent ductile damage model. Experiments were conducted on bulk adhesive specimens under constant temperature coupled with mechanical load, and the corresponding experimental results provided creep parameters for the simulation procedure as well as effective validation with the numerical results in this study. The results obtained from experiments and numerical simulations were also in good agreement. [ABSTRACT FROM AUTHOR]

The aim of this research was to develop an experimental–numerical approach to characterize the effect of salt spray environment on adhesively bonded joints and predict the degradation in joint strength. Experiments were conducted on bulk adhesive specimens and single lap joints (SLJs) under salt spray condition and the corresponding experimental results were reported. The environment degradation factor, Deg, was incorporated into a bilinear cohesive zone model (CZM) to simulate the degradation process of the joints. The degraded CZM parameters, determined from static tests on bulk adhesive, were imported into the CZM using an approximate moisture concentration gradient approach. The reduction in residual strength of SLJ under salt spray environment was successfully predicted through comparing the experimental and numerical results. [ABSTRACT FROM AUTHOR]

Process planning and scheduling are important stages in manufacturing, and good strategies can significantly improve the energy performance of manufacturing to achieve sustainability. In this paper, an innovative optimization approach has been developed to facilitate sustainable process planning and scheduling. In the approach, honey-bee mating and annealing processes are simulated to optimize multi-objectives including energy consumption, makespan and the balanced machine utilization. Experiments on practical cases show that the optimization results from this approach are promising in comparison with those from a genetic algorithm, a honey bee mating optimization algorithm, ant colony optimization and a simulated annealing algorithm, respectively. [ABSTRACT FROM AUTHOR]

Two new trinuclear Ni(II) complexes, [{Ni(L)(DMF)(μ-OAc)}2Ni] (1) and [{Ni(L)(EtOH)(μ-OAc)}2Ni]·2CH2Cl2 (2), have been successfully synthesized from a new asymmetric salamo-based hexa-dentate chelating ligand (H2L) and Ni(OAc)2·4H2O, and characterized by elemental analysis, IR and UV-Vis spectra, and X-ray crystallography. The binding ratio of H2L and Ni(II) ion has been confirmed by UV-Vis titration. All Ni(II) atoms are hexa-coordinated, and the complexes have octahedral configuration, though with difference in the solvent molecules (DMF/EtOH) involved in the coordination, composition of the hydrogen bond and chemical stability. This conclusion is confirmed by Hirshfeld surfaces analyses and Density Functional Theory (DFT). [ABSTRACT FROM AUTHOR]

We demonstrate a method to create nitrogen-vacancy (NV) centers in diamond using focused helium ion microscopy. Near-surface NV centers can be created with spatial resolution below 0.6 μm. We studied the density, creation efficiency, and spectral linewidths at optical and microwave frequencies for NV centers produced using various helium ion implantation doses. The optical linewidths are narrower than those of similar nitrogen-vacancy centers produced using nitrogen ion implantation. [ABSTRACT FROM AUTHOR]

A novel tetranuclear Ni(II) complex [Ni4(L)2(N3)4Cl(MeOH)3]·CH3COCH3 is synthesized via a symmetrical salamo-based ligand H2L, NiCl2·6H2O, and NaN3. The structure is characterized by elemental analyses, IR and UV-Vis spectroscopy, and X-ray diffraction analysis. The X-ray crystal analysis shows that Ni(II) atoms in the Ni(II) complex have distorted octahedral geometries. It is the key factor that the ligand containing 3-position methoxy groups gives rise to the formation of the tetranuclear Ni(II) complex. When anions are used to bridge two Ni2 atoms, there are two symmetrical open cubic structures. The Ni(II) complex forms a 3D supramolecular structure through intermolecular hydrogen bond interactions. Using the Hirshfeld surface to clarify interactions between the molecules, the percentages of C–H/H–C, O–H/H–O, and H–H/H–H contacts are calculated as 19.0%, 15.3%, and 54.0%, respectively. Density functional theory (DFT) studies show that the stability of the Ni(II) complex is much higher than that of H2L. The calculation of the fluorescence titration experiment can give K = 1.05·108 M–1, which further proves the stability of the Ni(II) complex. [ABSTRACT FROM AUTHOR]

Imaging fluorometry was applied to investigate the tolerance of Japanese honeysuckle ( Lonicera japonica Thunb.) of different ploidy levels to heat stress. Seedlings of L. japonica, the diploid cv. Damaohua and the tetraploid cv. Jiufengyihao, were exposed to heat stress of 42 °C for 6 h and a recovery for 10 h. Heat stress significantly decreased maximum photochemical efficiency, electron transport rate, effective quantum yield of photosystem 2, and photochemical quenching of both cultivars, but it decreased the non-photochemical quenching (NPQ) only in the tetraploid. Heat stress increased the content of total soluble sugars, proline, and malondialdehyde in both cultivars while it increased NPQ only in the diploid. Our findings suggest that the tetraploid showed to be more resistance to heat stress than the diploid of L. japonica, which was indicated by different chlorophyll fluorescence imaging techniques and metabolic changes. Moreover, the degree of recovery in the tetraploid was higher than that of the diploid. The tetraploid also possessed thicker epidermis (both upper and lower) and palisade tissue as well as denser pubescence. [ABSTRACT FROM AUTHOR]

The propagation of an initially-localized optical beam along two coupled modulated waveguides is investigated. A universal step-like structure emerges in the propagation process once $|\delta$ v/ $v_0|$ ~ 1 and T = 2 π/ $m v_0$, both for the linear and nonlinear optical waveguides. The reason is that the coupling between the two waveguides can be completely suppressed at z = m T or (2 m+1) T/2. When the nonlinearity is strong, assisted tunneling can be found for the initially-localized optical beam by slightly increasing the strength of the modulation. [ABSTRACT FROM AUTHOR]

The effects of Ganoderma lucidum polysaccharides (GL-PS) on renal complication in streptozotocin-induced diabetic mice have been investigated in the present study. C57BL/6J mice were made diabetic by injection of streptozotocin and GL-PS (125 and 250 mg kg- 1) was administered for 8 weeks. Body weight was monitored every week. Serum glucose, creatinine (Cr), blood urea nitrogen (BUN), triglyceride (TG) and urinary albumin excretion (UAE) were measured after 8 weeks of treatment. Glomerular size and mesangial matrix index were assayed by morphometric analysis. Renal expression of transforming growth factor-β1 (TGF-β1) were determined by immunochemistry. Renal malondialdehyde (MDA) level and superoxide dismutase (SOD) activities were also evaluated. GL-PS was able to reduce the serum Cr and BUN levels and UAE compared with diabetic model mice in a dose-dependent manner. Increasing serum glucose and triglyceride levels in diabetic mice could also be lowered by GL-PS. Moreover, GL-PS had the capacity to improve the renal morphometric changes and oxidative stress state of diabetic mice. In summary, GL-PS can improve the metabolic abnormalities of diabetic mice and prevent or delay the progression of diabetic renal complications. [ABSTRACT FROM AUTHOR]

Based on the moving least-squares (MLS) approach, an efficient meshless method is employed to generate the displacement functions for vibration analysis of elastic bodies. The equation of motion is established by following the standard procedure and the boundary conditions are imposed by applying penalty functions. As the displacement functions are expressed in terms of weight functions, the accuracy will depend on the parameters of the weight functions. Therefore, a parametric study is carried out to determine the best values for these parameters. To demonstrate the accuracy, modal analyses of the beams and plates with different boundaries have been carried out. In addition, the responses of these structures under dynamic excitation have been analyzed. The examples include simply supported beams subjected to sudden excitations and simply supported plates subjected to initial displacements. [Copyright &y& Elsevier]

OBJECTIVE: Following several reports of linkage of obesity related phenotypes to human chromosome 20q we sought to determine whether variations of the melanocortin 3 receptor (MC3R) gene are associated with obesity. DESIGN: We screened the MC3R gene coding region and approximately 2 kb of 5' and 3' flanking sequences for DNA variants in unrelated extremely obese women and average weight controls using polymerase chain reaction (PCR) single strand conformation polymorphism (SSCP) analysis and DNA sequencing. SUBJECTS: 124 unrelated extremely obese women (body mass index, (BMI) ≥ 40 kg/m²) and 85 average weight controls (BMI <27 kg/m²). MEASUREMENTS: Radiation hybrid (RH) mapping was performed to localize the MC3R gene. 5' and 3' flanking sequences of MC3R gene were cloned. PCR-SSCP and DNA sequencing were used to detect mutations in the MC3R gene coding region and flanking sequences. RESULTS: RH mapping localized the MC3R gene to 20q13, between markers D20S100 and D20S149. 1083 bp 5' and 653 bp 3' flanking region of the MC3R gene were cloned. A missense mutation (±241, codon 81 ATT/GTT, Ile → Val) was found in the IVIC3R coding region. Four more variants were detected in the 5' flanking sequence: -201(C → G), -239 (A → G), -762(A → T) and -769(T → C). Compared with controls, no significant allele frequency differences were found. Racial differences were found for the +241, -201, -239 and -762 polymorphisms. CONCLUSIONS: Several sequence variants were found in the MC3R gene coding region and in 5' flanking sequences. However, none of the variants were associated with obesity phenotypes. The linkage of extreme human obesity on 20q13 is likely caused by genes other than MC3R. [ABSTRACT FROM AUTHOR]

This article takes the 21 - 4N engine valve as the research object and studies the effects of die forging temperature (1 000 - 1 180 °C), die forging speed (0,15 - 200 mm / s) and friction coefficient (0,1 - 0,5) on die forging results. First, a finite element model (FEM) of the valve blank and die is established using Creo; next, the valve forging process is simulated using Deform - 3D; then, the response surface analysis method is used to analyze and discuss the results of die forging, and to optimize the process parameters with valve product damage as the optimization goal, and determine the best process parameters for 21 - 4N engine valve forging; finally, the obtained parameters are verified through experiments, and the experimental results and prediction results have a good consistency. [ABSTRACT FROM AUTHOR]

This study was conducted to explore the association between attempted suicides and body mass index (BMI, kg/m2) in a family sample of 2547 individuals. As a comparison, a national NESARC (the 2001–2002 National Epidemiologic Survey on Alcohol and Related Conditions) sample of 41 589 individuals was included to validate the observed association. Compared to average weight, extreme obesity showed significantly increased odds for attempted suicides both in family sample (odds ratio (OR)=3.37 and 95% confidence interval (CI)=1.59–7.13 for BMI=40–<50 kg/m2; OR=3.85 and 95% CI=1.71–8.66 for BMI50 kg/m2) and in NESARC sample (OR=2.11 and 95% CI=1.59–2.81 for BMI=40–<50 kg/m2; OR=2.56 and 95% CI=1.34–4.92 for BMI50 kg/m2) after adjustment for sociodemographic factors. Compared to general population, the risk for attempted suicide was 87 and 122% higher for those with BMI=40–<50 and 50 kg/m2, respectively. The pattern of results in the family and population studies indicates that extreme obesity is strongly associated with attempted suicide.International Journal of Obesity (2006) 30, 388–390. doi:10.1038/sj.ijo.0803119; published online 4 October 2005 [ABSTRACT FROM AUTHOR]

Licorice is one of the most-frequently-used Chinese herbs. Glycyrrhizic acid (GA), as the most important marker component in licorice, is biosynthesized by mevalonic acid (MVA) pathway and regulated by many key enzymes. Among them, β -amyrin synthase (β -AS) is responsible for the triterpene skeleton formation. In this paper, we tried to find out the influence of β - AS gene polymorphism on the GA biosynthesis. The contents of 18 α -glycyrrhizic acid (18 α -GA) and 18 β -glycyrrhizic acid (18 β -GA) in 60 licorice samples were assayed by HPLC. For the β-AS gene polymorphism analysis, six samples with high GA content and seven samples with low GA content were selected. Thirteen β-AS cDNA sequences were obtained and eleven haplotypes were determined. The full length of these β-AS cDNA sequences is 2289 bp, with a complete open reading frame (ORF), encoding 762 amino acid residues. Haplotype-3 was the major haplotype in the group with high GA content, while haplotype-8 was the major haplotype in the group with low GA content. The missense mutation sites between haplotype-3 and haplotype-8 were G/C at 104 bp and 106 bp, resulting in the mutations of serine/threonine at the 35th amino acid residue site and alanine/proline at the 36th amino acid residue site. The yeast expression vectors, GS115-BAS-3 and GS115-BAS-8, containing haplotype-3 or haplotype-8 were constructed, and later transformed into Pichia pastoris GS115 by electrotransformation, respectively. The catalytic efficiency of protein BAS-3 and BAS-8 expressed in the different recombinant P. pastoris GS115 strains were analyzed by GC–MS. It was showed that compared with BAS-8, BAS-3 had a higher catalytic activity. The relative expression analysis showed that there was a positive correlation between the expression level of β-AS gene and the content of GA. We hope this paper will provide a basis for functional gene studies involved in the biosynthetic pathway of GA and high-quality cultivated licorice selection in the future. • Two special β -AS haplotypes, haplotype-3 and haplotype-8 were the major haplotypes in the group with high/low content of glycyrrhizic acid, respectively. • Comparatively, haplotype-3 has a higher catalytic activity in Pichia pastoris GS115. • There was a positive correlation between the expression level of β-AS gene and the content of glycyrrhizic acid. • The β - AS gene polymorphism influenced the biosynthesis of glycyrrhizic acid. [ABSTRACT FROM AUTHOR]

We systematically study the structural, electronic, and magnetic properties of chromium sulfide YCrS by using density-functional theory. We find that antiferromagnetic order is more energetically favorable than ferromagnetic state and near the Fermi level the main occupation is from Cr 3 d states. [ABSTRACT FROM AUTHOR]

Photosynthetic rate (P) and chlorophyll (Chl) fluorescence induction of source leaves in response to a low sink demand created by girdling the branch (GB) between the root-tuber-system and the leaves were studied in Dahlia pinnata L. cv. Rigolet during the stage of rapid tuber growth in the greenhouse. GB resulted in significantly lower values of P, stomatal conductance (g), and transpiration rate (E), but in higher leaf temperature (T) compared with those of controls. With exception of maximum quantum yield of photosystem 2 (PS 2) photochemistry (F/F) and maximum ratio of quantum yields of photochemical and concurrent non-photochemical processes in PS 2 (F/F), no significant differences were observed in Chl fluorescence parameters between girdled and control leaves on days 1 and 2 after GB, indicating no apparent damage in the photosynthetic apparatus. However, longer girdling duration resulted in higher non-photochemical Chl fluorescence quenching (NPQ), but lower F/F, actual efficiency of energy conversion in PS 2 under steady-state conditions (Φ), and photochemical quenching coefficient (qP) in comparison with controls from 10:00 to 16:00 or 15:00 on days 4 and 5, respectively, indicating reversible injury in the photosynthetic apparatus. [ABSTRACT FROM AUTHOR]

A novel technology of designing interface layer using macromolecule resin element, polystyrene, to enhance the damping capacity of aluminium foam is successfully attempted. The interface layer was fabricated by coating a polystyrene film on the pore surface of the aluminium foam using a similar sol–gel technology. Results of the measurements show that the introduction of interface layer not only improves the mechanical strength, but also significantly enhances the damping capacity that can be an order increase relative to the corresponding aluminium foam matrix in the temperature range of room temperature to 80°C. The involved damping mechanisms include the intrinsic damping and interface damping of the constituents. The latter should be dominant as a result of relatively easy energy dissipation through interfacial friction. [ABSTRACT FROM AUTHOR]

A new approach to converting a design feature model (DFM) to a machining feature model (MFM) step-by-step during a design process has been proposed. In the approach, the MFM is incrementally set up and updated through performing a local machining feature recognition on certain areas of a design part’s B-rep when its design features are updated. The areas to be recognized as machining features are determined through geometric reasoning according to the statuses of the DFM and the dynamically generated MFM of the part. To facilitate the above geometric reasoning, a dynamic link list (DLL) has been developed to record the changed topological elements during the design process and the relationships between the DFM and the MFM. Based on the automatic and effective conversion process from design models to machining feature models, the proposed approach can support the establishment of a concurrent product development environment to link product design and manufacturing processes seamlessly. [ABSTRACT FROM AUTHOR]

The 3Cr23Ni8Mn3N heat-resistant steel was subjected to isothermal constant strain rate compression experiments using a Gleeble - 1 500D thermal simulator. The thermal deformation behavior in the range of deformation temperature 1 000 - 1 180 °C and strain rate 0,01 - 10 s-1 was studied. Based on experimental data, the stress-strain curves of 3Cr23Ni8Mn3N were established. And the constitutive relation of BP neural network (3 × 10 × 10 × 1) was constructed. The flow stress was predicted and compared by the ANN constitutive model. The correlation coefficient (R) is 0,999, and the average relative error (AARE) is 0,697%. The results show that the ANN constitutive model has high accuracy for predicting the thermal deformation behavior of 3Cr23Ni8Mn3N. The model can provide a good reference value for thermal processing. [ABSTRACT FROM AUTHOR]

When a Computer Aided Design (CAD) model is shared in cloud for collaboration, it is a challenge to encrypt the confidential design features of the model for effective knowledge protection. This paper presents a novel encryption approach, which is based on geometric transformation encryption mechanisms on feature-based CAD models in supporting cloud-enabled collaboration. The innovation of the approach is centered on an Enhanced Encryption Transformation Matrix (EETM), which is characterized parametric, randomized and self-adaptive for feature encryption. Controllable parameters for transforming features in terms of zoom and deformation are defined in the EETM to facilitate users to conduct encryption transformation flexibly. A random probability mechanism is embedded into the parameters of the EETM in order to guarantee the security of the encrypted model. Furthermore, the parameters in the EETM are further enhanced to be self-adaptive to ensure the geometric validity of the encrypted model. The approach has been validated via a number of complex models to demonstrate the applicability and effectiveness for industrial applications. [ABSTRACT FROM AUTHOR]

Psoralea Fructus, the dried and ripe fruit of Psoralea corylifolia L., have been used as traditional medicine. There is substantial evidence that multiple constituents are responsible for the beneficial effects of this medicine. To effectively control the quality of this herbal medicine, HPLC fingerprint analysis was performed on a SinoChrom ODS-BP column with mobile phase of a gradient prepared from H2O and CH3CN, which the conditions used for gradient elution were: 0-10 min, 5-45% CH3CN; 10-45 min, 45-70% CH3CN; 45-50 min, 70-100% CH3CN; 50-60 min, 100-100% CH3CN, and the flow rate was 1.0 ml/min. It was obtained on the basis of the chromatographic data from 28 batches of samples, which contained 26 common peaks and 13 peaks were identified by the electrospray ionization-mass spectrometry as psoralen, isopsoralen, isobavachin, neobavaisoflavone, bavachin, corylin, broussochalcone B, psoralidin, isobavachalcone, bavachinin, corylifol A, bavachalcone and backuchiol. The contents of these 13 compounds were also simultaneously examined. By using principal component analysis, 28 batches of samples collected from 6 producing locations with different collecting time were evaluated and differentiated. In summary, the data as described in this study offer valuable information for quality control and proper use of Psoralea Fructus. [ABSTRACT FROM AUTHOR]

Adhesively bonded joints are widely used in automotive industry. Adhesively bonded joints permit to have more uniform stress distributions, join complex shapes, and reduce the weight of the structures. The requirement to reduce the weight of automobiles is also increasing the application of composites. In this article, CFRP (carbon fiber-reinforced plastics) composite was used in experimental tests. In many cases, adverse environments cause non-negligible degradation in joints mechanical performance. So a combined experimental–numerical approach was developed to characterize the effect of cyclic-temperature environment on adhesively bonded joints. Experimental tests were carried out on single-lap joints with CFRP and steel adherend in a cyclic-temperature environment. A cohesive zone model was taken into consideration to predict the results observed during the experimental tests and an environmental degradation model was developed. Scanning electron microscopy was utilized to investigate the fracture surfaces. [ABSTRACT FROM PUBLISHER]

The aim of this research was to develop numerical modelling techniques for simulating the simultaneous effects of moisture, elevated temperature, and applied load on the performance of adhesively bonded joints. Associated experimental data are also reported. The degradation process of the joints was modelled using a fully-coupled approach, with the moisture concentration affecting the stress distribution and the stress state affecting the moisture diffusion analyses simultaneously. Further, the stress analysis contains a moisture-dependent creep model to accommodate viscous effects, and both swelling and thermal strains were included in the simulation. The governing parameters adopted in the modelling procedure were determined from experimental work based on the bulk adhesive. The joint response was monitored throughout the ageing process and good correlation was found between the experimental and numerical results. [ABSTRACT FROM PUBLISHER]

A novel surface treatment for 316L SS by using magnetisation was studied, and the effects on the electrochemical behaviour and semiconductor properties were measured by potentiodynamic polarisation, electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis in 3·5 wt-% NaCl solution. The results showed that the open circuit potential, corrosion potential Ecorr and charge transfer resistance Rt of the specimen markedly increased after the magnetisation treatment, while the passive current Ip decreased. Mott-Schottky analysis indicated that the donor densities of the passive films on the treated and untreated specimen are 3·83×1027 and 5·09×1027 m-3 respectively. In addition, the flat band potential of the treated specimen is more negative than that of the untreated specimen. These parameters (Nd and Efb) are closely related to the effects of magnetisation treatment on the anodic dissolution process of 316L SS. [ABSTRACT FROM AUTHOR]

We report an experimental and theoretical study of very low-energy photoelectrons in tunneling ionization process from noble gas atoms interacting with ultrashort intense infrared laser pulses. A universal peak structure with electron energy well below 1 eV in the photoelectron spectrum, corresponding to the double-hump structure in the longitudinal momentum distribution, is identified experimentally for all atomic species. Our quantum and semiclassical analysis reveal the role of long-range Coulomb potential in the production of this very low-energy peak structure. [ABSTRACT FROM AUTHOR]

The crystal structure, mechanical properties and electronic structure of ground state BeH2 are calculated employing the first-principles methods based on the density functional theory. Our calculated structural parameters at equilibrium volume are well consistent with experimental results. Elastic constants, which well obey the mechanical stability criteria, are firstly theoretically acquired. The bulk modulus B, Shear modulus G, Young's modulus E, and Poisson's ratio υ are deduced from the elastic constants. The bonding nature in BeH2 is fully interpreted by combining characteristics in band structure, density of states, and charge distribution. The ionicity in the Be-H bond is mainly featured by charge transfer from Be 2s to H 1s atomic orbitals while its covalency is dominated by the hybridization of H 1s and Be 2p states. The Bader analysis of BeH2 and MgH2 are performed to describe the ionic/covalent character quantitatively and we find that about 1.61 (1.6) electrons transfer from each Be (Mg) atom to H atoms. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of chromosome doubling on ozone tolerance, we compared the physiological responses of a diploid honeysuckle ( Lonicera japonica Thunb.) and its autotetraploid cultivar to elevated ozone (O3) exposure (70 ng g−1, 7 h d−1 for 31 d). Net photosynthetic rate ( PN) of both cultivars were drastically ( P<0.01) impaired by O3. Although there were significantly positive correlation between PN and stomatal conductance ( gs) in both cultivars under each treatment, the decreased gs in O3 might be the result rather than the cause of decreased PN as indicated by stable or increasing the ratio of intercellular to ambient CO2 concentration( Ci/ Ca). PN under saturating CO2 concentration ( PNsat) and carboxylation efficiency (CE) significantly decreased under O3 fumigation, which indicated the Calvin cycle was impaired. O3 also inhibited the maximum efficiency of photosystem II (PSII) photochemistry in the dark-adapted state (Fv/Fm), actual quantum yield of PSII photochemistry (ΦPSII), electron transport rate (ETR), photochemical quenching coefficient (qP), non-photochemical quenching (NPQ), the maximum in vivo rate of Rubisco carboxylation (Vcmax) and the maximal photosynthetic electron transport rate (Jmax) which demonstrated that the decrease in PN of the honeysuckle exposed to elevated O3 was probably not only due to impairment of Calvin cycle but also with respect to the light-harvesting and electron transport processes. Compared to the diploid, the tetraploid had higher relative loss in transpiration rate ( E), ( gs), ( PNsat), Vcmax and Jmax. This result indicated that the Calvin cycle and electron transport in tetraploid was damaged more seriously than in diploid. A barely nonsignificant ( P=0.086) interaction between O3 and cultivar on PN suggested a higher photosynthetic sensitivity of the tetraploid cultivar. [ABSTRACT FROM AUTHOR]

The well distributed open cellular porous copper was fabricated by present powder metallurgy technique based on space holder method, Depending on the volume fraction and size of the space holding particle, the porosity can be varied in the wide range of 30–85% and pore size from micron to millimetre in magnitude of order respectively. The damping behaviour and related relative dynamic modulus of the porous copper were investigated by a multifunction internal friction apparatus as a function of temperature from room temperature to 600°C. The results of investigation disclose that the porous copper can obtain a higher damping capacity than that of bulk one. In addition to this, an internal friction peak was found in the spectra of internal friction against temperature for the porous copper, it was proposed that the viscous sliding of the grain boundaries should be responsible for the appearance of the peak, and the dependence of the peak on porosity can be understood in terms of the anelastic relaxation mode of grain boundary. [ABSTRACT FROM AUTHOR]

Aims: To construct a transgenic Bacillus mucilaginosus strain to increase the secretion capability of a wild-type isolate of B. mucilaginosus D4B1 to hydrolyse phytate phosphorus, which can be used as a microbial fertilizer in field application. Methods and Results: We constructed a phytase secreting expression vector pSP43 with a mini-Tn5 transposon and a Aspergillus fumigatus phytase expression cassette. The vector pSP43 was successfully transferred into the wild-type B. mucilaginosus using the particle bombardment method, and three transgenic strains with a stable copy of phytase expression cassette integrated into the chromosome of the B. mucilaginosus by Tn5 transposition were selected. The phytase activity of the engineered strains increased 36–46-fold when compared with the wild-type strain of D4B1. Conclusions: The A. fumigatus phytase gene can be expressed under the direction of p43 promoter in B. mucilaginosus. The expression protein is secreted extracellularly and newly constructed strains showed a high phytase activity. Significance and Impact of the Study: A transgenic Bacillus strain by the particle bombardment method was constructed. [ABSTRACT FROM AUTHOR]

Aim: Thalassaemia is a good candidate disease for control by preventive genetic programmes in developing countries. Accurate population frequency data are needed for planning the control of thalassaemia in the high risk Guangdong Province of southern China. Methods: In total, 13 397 consecutive samples from five geographical areas of Guangdong Province were analysed for both hoematological and molecular parameters. Results: There was a high prevalence of carriers of α thalassaemia (8.53%), β thalassaemia (2.54%), and both α and β thalassaemia (0.26%). Overall, 11 .07% of the population in this area were heterozygous carriers of α and β thalassaemia. The mutation spectrum of α and β thalassaemia and its constitution were fully described in this area. This study reports the true prevalence of silent α thalassaemia in the southern China population for the first time. In addition, two novel mutations that give rise to α thalassaemia, one deletion resulting in β thalassaemia, and a rare deletion (- - THAI allele) previously unreported in mainland China were detected. The frequency of the most common mutation, the Southeast Asian type of deletion (- - SEA, accounting for 48.54% of all α thalassaemias) was similar to the total of two α+ tholassaemia deletions (-α3.7 and -α4.2, accounting for 47.49% of α thalassaemia). Conclusion: Both α and β thalassaemia are widely distributed in Guangdong Province of China. The knowledge gained in this study will enable the prolected number of pregnancies at risk to be estimated and a screening strategy for control of thalassaemia to be designed in this area. [ABSTRACT FROM AUTHOR]

A letter to the editor discussing a case study of JAK2 mutation in Chinese myeloproliferative disease is presented.

Background: Colorectal cancer is the third most common cancer in the world, arising mostly from pre-existing adenomatous polyps (adenomas) of the large bowel. Patients with colorectal adenomas are at increased risk of colorectal cancer because of a high recurrence rate for adenomas. We followed a cohort of 1490 patients with rectal adenomas to determine whether recurrence might be related to pathologic characteristics of the initial adenomas.Methods: The patients were identified in Haining County, China, from 1977 through 1978 by means of examination with a 15-cm rigid sigmoidoscope. They were followed by endoscopic examination at years 2, 4, 6, 11, and 16 after their initial polypectomy. New adenomas in the rectum were identified in 280 patients in these follow-up examinations.Results: Statistically significant twofold to threefold elevated risks of metachronous (recurrent) adenomas were observed for patients who had more than two initial adenomas or whose most advanced initial adenoma was more than 1.0 cm in size, was of villous/tubulovillous type, or showed moderate to severe dysplasia. Much stronger associations were observed for advanced metachronous neoplasms, which are defined as cancers or adenomas with severe dysplasia, with multivariate adjusted relative risks (95% confidence interval) of 4.2 (1.8-9.9) for a large initial adenoma (>1.0 cm), 8.1 (4.2-15.6) for villous/tubulovillous architecture, and 14.4 (5.0-41.3) for severe dysplasia. In particular, patients who had a large (>1.0 cm) adenoma with severe dysplasia at baseline had a relative risk of 37 (7.8-174.7) of developing advanced metachronous neoplasms compared with patients who had small adenoma(s) with mild dysplasia.Conclusions: The risk of metachronous adenomas is closely related to the pathology of initial adenomas, thus allowing identification of a high-risk group of adenoma patients for close surveillance after their initial polypectomy. [ABSTRACT FROM AUTHOR]