Search

Terahertz (THz) single-pixel imaging has received major research attention because of the lack of a suitable high-resolution array detector for THz imaging applications. Improving both imaging speed and quality has become a research hotspot for this field in recent years. In this study, a terahertz single-pixel imaging system with Hadamard spatial encoding was constructed by using optically induced semiconductor materials to perform THz wave modulation. Sparse coding was added to the system's reconstruction algorithm to enhance imaging quality. Numerous image patches were then collected from a natural image set to train an overcomplete dictionary and each patch in the measured image was reconstructed through sparse representation. To validate the effectiveness of the proposed algorithm, the reconstruction performances of different algorithms were compared under various conditions (i.e., with sampling rates varying from 5 to 100% and with noise levels within a signal-to-noise ratio range of 10–50 dB). The proposed algorithm, in combination with sparse representation of an overcomplete dictionary, showed a higher peak signal-to-noise ratio and a lower mean square error than both the inverse Hadamard transform (IHT) and TVAL3 algorithms. Finally, THz imaging experiments were performed to validate the algorithm's reconstruction performance at sub-Nyquist sampling rates. The experimental and simulation results coincided closely, thus indicating that the use of the proposed algorithm enhances the signal-to-noise ratio of the reconstructed image, reduces its mean square error, and retains greater image detail. The proposed algorithm was demonstrated to be the preferred choice for THz single-pixel imaging applications. [ABSTRACT FROM AUTHOR]

T8 treatment includes solution treatment, cold working and artificial aging treatment. T8 treatment can greatly improve the hardness and strength of 2024 aluminum alloy without reducing the corrosion resistance. The effect of 0, 1, 2, 3, and 4% cold-drawing deformation on the microstructures of the alloy was observed by transmission electron microscopy, and properties of the alloy was investigated by hardness tests, tensile tests and electrochemical corrosion tests. The results show that the mechanical properties and corrosion resistance of cold-drawing deformed 2024 aluminum alloy are better than those of non-deformed alloy. Compared with AA2024-T6, AA2024-T8 with 2% cold-drawing deformation has a higher hardness by 11.3%, and a higher tensile strength by 10.8%. The improvement of the properties of AA2024-T8 is mainly due to the interaction between dislocations and precipitates. With the increase in cold-drawing deformation, the nucleation points of precipitates in AA2024-T8 gradually increase, and precipitates are gradually coarsened under the same artificial aging treatment. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to simulating and monitoring the dynamic performance of high-speed bearings, a critical component in automated industrial production for system efficiency and safety. The newly developed theoretical framework allows for detailed analysis of dynamic responses in these bearings, especially under high-speed conditions. The Short-Time Fourier Transform (STFT) is used to capture time-frequency domain characteristics, while real-time condition monitoring is achieved through a deep learning-based Convolutional Neural Network, enhanced by a multi-head attention mechanism. This method enables managing large datasets, real-time surveillance, and accurate prediction of bearing conditions. Ultimately, this approach provides an innovative perspective for fault diagnosis and performance assessment of high-speed bearings in complex production environments. [ABSTRACT FROM AUTHOR]

We present a super sub-Nyquist Hadamard single-pixel terahertz (THz) imaging system in which the THz waves are modulated by a digital micromirror device and a laser driver. Spatial coding of the THz radiation is performed using the cake-cutting (CC)-order Hadamard basis. THz images are reconstructed from a series of coding sequences of the measurement intensity. We prove that with the use of super sub-Nyquist sampling, single-pixel THz imaging with 87% fidelity and a signal-to-noise ratio of more than 23 dB can be achieved using 10% of the CC-order Hadamard basis patterns. The total variation regularization algorithm is shown to have higher robustness to noise than the Hadamard transform and thus offers a good technical solution for single-pixel THz imaging. [ABSTRACT FROM AUTHOR]

Two new coordination polymers [Zn(L)(Bpa)·H2O]n (I) and [Zn(L)(Bip)]n (II) (H2L is 4‑hydroxyisophthalic acid, Bpa is 1,2-bis(4-pyridyl)ethane, Bip is 3,5-bis(imidazole-1-yl)pyridine) have been prepared and characterized by element analysis, powder X-ray diffraction, and single-crystal X-ray diffraction (CCDC nos. 2073592 (I), 2073594 (II)). The single crystal X-ray diffraction studies reveal that compound I is a 1D chain structure, in which zinc(II) is four-coordinated with a tetrahedral geometry. Complex II is a 2D layer structure, in which zinc(II) is four-coordinated. Complexes I and II are further extended into three-dimensional supramolecular network via hydrogen bonds and π···π interactions. The solid-state luminescent properties of compounds I and II have been investigated. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, {[Zn(3-Nbdc)(bip)]·2H2O}n (1) and {[Co(3-Nbdc)(bip)(H2O)]0.25H2O}n (2) (H23-Nbdc = 3-nitrobenzene-1,2-dicarboxylic acid, bip = 3,5-bis(1-imidazolyl)pyridine) were synthesized under the hydrothermal conditions and characterized by single crystal X-ray diffraction and elemental analysis. In 1, the Zn(II) ion forms a slightly distorted [ZnO2N2] tetrahedron by two carboxylate oxygen atoms and two nitrogen atoms. Adjacent Zn(II) neighbors are linked by 3-Nbdc dianions adopting monodentate coordination mode to form 1D Zn-carboxylate chain, which is further extended by bip molecules to produce a two-dimensional thick layer. For complex 2, two six-coordinated Co(II) ions with different coordination environments are alternately connected by 3-Nbdc dianions and bip ligands along different directions to generate a two-dimensional grid layer. Furthermore, Powder X-ray diffractions, FTIR spectra and thermogravimetric analyses are also investigated. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, {[Mn2(L)(H2O)2]·H2O}n (1) and {[Co2(L)(H2O)2]·H2O}n (2) (H4L = 2-(2,4,6-tricarboxylphenyl)-6-carbxoylbenzimi-dazole), have been synthesized under hydrothermal conditions and characterized by element analysis, powder XRD and single crystal X-ray diffraction. The results indicate complex 1 as a 2D carboxylate layer structure, which is extended by hydrogen bonds resulting in a three-dimensional supramolecular network. The structure of 2 is isomorphic to that of 1. Magnetic measurements demonstrate weak antiferromagnetic interactions between the neighbouring Mn(II) ions in 1. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the possibility of using the methylation level of PAX1/ZNF582 gene as molecular marker to differentiate the progression of cervical cancer. Methods: From January 2016 to March 2018, 150 patients, who were admitted to Cervical Disease Diagnosis and Treatment Center of Xuzhu Maternity and Child Care Hospital, were enrolled in this study. Patients were classified into chronic cervicitis (for 19 cases), low-grade squamous intraepithelial lesion (LSIL) (18 cases), high-grade squamous intraepithelial lesion (HSIL) (37 cases) and squamous cell carcinoma (SCC) (31 cases). All patients underwent several tests including Thin-prep cytology test (TCT), HPV DNA detection and detection of methylation level of PAX1/ZNF582 genes. Results: For diagnosis of HSIL, the area under curve (AUC) was 0.878 (95% CI 0.806 ~ 0.950); the threshold for PAX1 was 12.285, the sensitivity and specificity were 91.9% and 72.8%, respectively. The AUC of ZNF582 gene detection was 0.900 (95% CI 0.842 ~ 0.959), the threshold was 11.56, while the sensitivity and specificity were 97.3% and 76.7%, respectively. Among various tests we conducted, PAX gene detection methods showed the highest specificity (97.30%). PAX1/ZNF582 gene detection method demonstrated the highest accuracy. Conclusions: For patients with high-grade cervical lesion and cervical cancer, the methylation level of PAX1/ZNF582 gene could be applied as a noteworthy biomarker for diagnosis and for cervical cancer classification. [ABSTRACT FROM AUTHOR]

Lung cancer is the main cause of cancer incidence and mortality around the world. Prucalopride is an agonist for the 5-hydroxytryptamine 4 receptor, but it was unknown whether prucalopride could be used to treat lung cancer. To investigate the biological effects of prucalopride on proliferation, apoptosis, invasion, and migration of lung cancer cells, and its underlying molecular mechanism in the progression of lung cancer, we performed this study. The Cell Counting Kit 8 assay was used to measure the proliferation of A549/A427 lung cancer cells treated with prucalopride. Transwell assay was applied to evaluate cell invasion and migration. Cell apoptosis was detected by flow cytometry and Western blot analyses. The expression levels of related proteins in the PI3K/AKT/mTor signaling pathway were analyzed by Western blotting. Prucalopride inhibited the proliferation, invasion, and migration of A549/A427 human lung cancer cells. It also induced autophagy and apoptosis and decreased the expression of the phosphorylated protein kinase B (AKT) and mammalian target of rapamycin (mTor) in these cells. This study implied an inhibitory role for prucalopride in the progression of human lung cancer. [ABSTRACT FROM AUTHOR]

To clarify the electrical property of grain boundaries, the fine-grained ceramics CaCu3Ti4O12 have been treated with the hydrofluoric acid to remove the parts of grain boundaries. The dielectric response difference between the etched samples and the pristine ones indicates that the ceramic CaCu3Ti4O12 consists of insulating or semiconducting grains with conducting grain boundaries. Therefore, the giant dielectric phenomenon is supposed not to derive from the grain boundary barrier layer capacitance effect. The possible mechanism is discussed. [ABSTRACT FROM AUTHOR]

Using observations from the GPM Tropical Cyclone Overpass Dataset and Himawari-8, this study statistically analyses the tropical cyclones (above Typhoon categories) in the Northwest Pacific during the tropical cyclone (TC) frequent period (from May to October) of 2014–2018. Moreover, a case (Super Typhoon "Mangkhut") was analysed in detail. This study uses a semi-manual method to identify three life cycle stages of tropical cyclones: developing stage, mature stage, and dissipating stage. The statistical results show that the distribution of precipitation and latent heat varies with positions and the tropical cyclone has the maximum precipitation (11.62 mm/h) at the mature stage along with the maximum convection ratio (22.97%) at the developing stage. It is most obvious that the release of latent heat in the upper cloud at developing stage and in the lower cloud at mature stage. The latent heat profile of convective precipitation presents a "bottom-heavy" structural, and the stratiform precipitation has a "top-heavy" latent heat profile. The proportion of stratiform precipitation to total precipitation (74.31%) is the largest, but the average precipitation of the stratiform (4.12 mm/h) is lower than the average precipitation of convective clouds (10.55 mm/h). The average particle radius of the stratiform precipitation is 1.13 mm, while the average precipitation particle radius of the convective cloud precipitation is 1.79 mm. Based on these statistical results, this paper briefly analyses the characteristics of cloud precipitation microphysical mechanisms in three life cycle stages. Besides, the latent heating profile distribution found in this study are related to the vertical variation of precipitation rate, which are different in terms of the type of precipitation cloud. [ABSTRACT FROM AUTHOR]

In order to solve the problem of "data island" in the management of Fuzhou historical buildings. This paper analyzes historical building management needs and historical building management indicators. Then the data warehouse model of historic buildings is constructed by using dimension modeling method, and a set of data warehouse of Fuzhou historic buildings is designed and established. Finally, a historical building management platform was built on the basis of the historical building data warehouse, which realized the entry, standardization, extraction and cleaning of historical building management data. It provides data support for data mining of historic buildings in order to realize the protection, activation, utilization and standardized management of Fuzhou historic buildings. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, {[Cd(Hmph)(Itmb)] ∙ H2O}n (I) and [Zn(Hmph)(Bpt)2]n (II) (H2Hmph = homophthalic acid, Itmb = 1-(imidazo-1-yl)-4-(1,2,4-triazole-1-ylmethyl)benzene, Bpt = 3,5-bis(4-pyridyl)-1,2,4-triazole) have been prepared and then characterized by single crystal X-ray diffraction (CIF files CCDC nos. 1842595 (I), 1842591 (II)). Complex I shows a 2D layer structure containing Cd-carboxylate chains linked further by itmb coligands, and the ultimate 3D supramolecular structure is stacked through significant π–π interactions. Complex II displays a zigzag Zn-carboxylate chain structure, which is further extended to the final 3D supramolecular structure by hydrogen-bonding and π–π interactions. TGA experiments indicate that complex I and II have high thermal stabilities because they can maintain framework integrity until 275 and 315°C, respectively. And in comparison, with the free ligands, the fluorescent properties of both CPs show significant blue-shift. [ABSTRACT FROM AUTHOR]

Two pairs of primers (GHSR-3, GHSR-4) were used to amplify GHSR gene of Boer goat, Yaoshan goat and black goat. Totally two mutation sites (SNP loci), G200A and T628C were detected in amplification fragments of GHSR-3 and GHSR-4 respectively. For locus G200A, allele frequencies of G and A in Yaoshan goat, Boer goat and black goat were 0.637/ 0.595/0.827 and 0.363/0.450/0.173, respectively, which indicated that G was the dominant allele in three goat populations. G200A was synonymous mutation. For locus T628C, allele frequencies of C and T in Yaoshan goat, Boer goat and black goat were 0.466/0.449/0.458 and 0.534/0.551/0.542 respectively. Clustering analysis based on GHSR gene sequences of different species showed that Boer goat, Yaoshan goat and black goat were clustered with Capra hircus firstly, then clustered with Ovis aries and Pantholops hodgsonii, and finally clustered with cattle and whale. [ABSTRACT FROM AUTHOR]

Two new coordination polymers {[Zn(HL)(HBpp)] · H2O}n (I) and [Cd(HL)(HBpe)]n (II) (H4L = 5-(2,3-dicarboxy phenoxy) isophthalic acid, Bpp = 1,3-bis(4-pyridyl)propane, Bpe = 1,2-bis(4-pyridyl)ethylene) were prepared and characterize by element analysis, powder XRD and single crystal X-ray diffraction (CCDC nos. 1836060 (I), 1844999 (II)). The single-crystal X-ray diffractions reveal that the complex I is a 2D carboxylate layer with the HBpp suspension arms, in which the zinc(II) is four-coordinated with a tetrahedral geometry. Compound II is a 1D Cd(II)-carboxylate chains, in which the cadmium(II) is seven-coordinated with a distorted pentagonal bipyramidal geometry. Complexes I and II are further extended into three-dimensional supramolecular framework via hydrogen bonds. The solid state luminescent properties of compounds I and II have been investigated. [ABSTRACT FROM AUTHOR]

Salinization disturbs metabolic processes of plants and results in reduced growth and productivity. In our study, the Dongnong 8809 variety of triticale (×Triticosecale Wittmack) was evaluated for its physiological responses to salt stress during the seedling stage. We evaluated biomass production, relative chlorophyll content, chlorophyll fluorescence, and leaf gas-exchange parameters. Our results indicated that salt stress greatly reduced matter accumulation, SPAD value, photosynthetic capacity. However, seedlings treated with exogenous sugars showed significantly enhanced matter accumulation, SPAD value, quantum yield of PSII, electron transport rate, net photosynthetic rate, decreased stomatal limitation value, and improved photosynthetic capacity compared to seedlings treated with salt stress alone. Exogenous glucose and sucrose can alleviate the inhibitory effect of salt stress on the growth of triticale, and of the two exogenous sugars, sucrose had a stronger alleviating effect than that of glucose under salt stress. [ABSTRACT FROM AUTHOR]

Tea plant (Camellia sinensis [L.] O. Kuntze) is a woody crop of high economic importance worldwide; however, information on the molecular mechanisms underlying the regulation of flower development in this species is limited. In the present study, two GLOBOSA (GLO)-like MADS-box genes, CsGLO1 and CsGLO2, were isolated from C. sinensis 'Ziyangzhong' and were characterized to elucidate their roles in flower development. We found that CsGLO1 and CsGLO2 are nuclear-localized transcription factors without transactivation ability but with a robust interaction. They have similar patterns of expression, both mainly restricted to petals and stamens. Moreover, ectopic expression of either CsGLO1 or CsGLO2 in Arabidopsis thaliana resulted in a partial conversion of sepals to petals, suggesting full GLOBOSA functional activity. Our results indicate that CsGLO1 and CsGLO2 paralogs might redundantly contribute to petal and stamen, providing the first insight into their role in tea plant flower development. [ABSTRACT FROM AUTHOR]

We report on measurements of the dielectric permittivity of NiO-based ceramics doped with Zr (ZNO). Samples were prepared by the traditional solid-state reaction method. The concentration of Zr has an effect on the dielectric properties of ZNO ceramics. High permittivity values (∼104) were observed which remain almost constant from 200 K to 350 K at low frequencies. The high-dielectric-constant response of the ZNO ceramics is attributed mainly to a grain boundary (internal) barrier layer capacitance. [ABSTRACT FROM AUTHOR]

Background Malnutrition is a common and critical problem that influences outcome in cancer patients. Body composition reflects a patient's metabolic profile and physiologic reserves, which might be the true determinant of prognosis. In the present study, which aimed to identify valuable new prognostic indicators, we investigated the association between computed tomography--quantified body composition and short-term outcomes after gastrectomy for gastric cancer. Methods Skeletal muscle index, mean muscle attenuation, and ratio of visceral-to-subcutaneous adipose tissue area (VSR) were calculated from preoperative computed tomography images. Low skeletal muscle index, low mean muscle attenuation, and high vsr were respectively termed "sarcopenia," "myosteatosis," and "visceral obesity." The association of body composition with postoperative complications and serum markers of nutrition and inflammation after radical gastrectomy were analyzed. Results The overall complication rate was significantly higher in the sarcopenia (62.5% vs. 27.3%, p = 0.001) and myosteatosis groups (38.2% vs. 4%, p = 0.002). Patients with visceral obesity had a higher incidence of inflammatory complications (20.3% vs. 6.5%, p = 0.01). Multivariate logistic regression analysis demonstrated that sarcopenia (p = 0.013), myosteatosis (p = 0.017), and low serum retinol-binding protein (p = 0.019) were independent risk factors for overall complications. Compared with control subjects, patients with sarcopenia had lower postoperative levels of serum retinol-binding protein (p = 0.007), and patients with visceral obesity had higher levels of C-reactive protein (p = 0.026). Conclusions Sarcopenia, myosteatosis, and visceral obesity were significantly associated with increased rates of postoperative complications and affected the postoperative nutrition and inflammation status of patients with gastric cancer. [ABSTRACT FROM AUTHOR]

Two Mn(II) coordination polymers, {[Mn3 (Pfca)6(Phen)2] · 2DMF}n (I) and [Mn(Pfca)2(Phen)(H2O)]n (II) (HPfca = 4-fluorocinnamic acid, Phen = 1,10-phenanthroline), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and singlecrystal X-ray diffraction (CIF files CCDC nos. 967513 (I), 1542972 (II)). Complex I crystallizes in the triclinic crystal system, space group Pī with a = 11.0821(11), b = 12.2632(12), c = 15.0288(15) Å, α = 87.3760(10)°, β = 88.4610(10)°, γ = 81.2220(10)°, V = 2016.0(3) Å3, ρc = 1.369 g/cm3, Mr = 1662.25, Z = 1, F(000) = 853, μ = 0.543 mm-1, the final R = 0.0592 and wR = 0.1681 for 15498 observed reflections with I > 2σ(I). Complex II is of monoclinic system, space group P21/c with a = 18.0539(19), b = 8.5806(9), c = 18.758(2) Å, β = 116.5700(10)°, V = 2599.0(5) Å3, ρc = 1.491 g/cm3, Mr = 583.44, Z = 4, F(000) = 1196, μ = 0.567 mm-1, the final R = 0.0337 and wR = 0.0853 for 18139 observed reflections with I > 2σ(I). Complex I features linear Mn(II)-trinuclear units, which form 1D chain structure through F···F weak interactions, and complex II is 1D polymeric Mn(II)-chains. Antiferromagnetic coupling interactions exist within Mn(II)- carboxylate trinuclear in I (J =-0.40 cm-1) and Mn(II)-carboxylate chain in II (J =-0.45 cm-1). [ABSTRACT FROM AUTHOR]

Two new complexes {[Zn(H2L)(Bpp)] . H2O}n (I) and {[Ag(H3L)(Bpp)] . 0.25H2O}n (II) (H4L = 5-(2,3-dicarboxy phenoxy) isophthalic acid, Bpp = 1,3-bis(4-pyridyl)propane) were prepared and characterized by single crystal X-ray diffraction (XRD) (CCDC nos. 1578523 (I), 1578529 (II)), element analysis and powder XRD. Compound I showed a one-dimensional chain structure, in which the zinc(II) ion is fourcoordinated with a tetrahedral geometry. Compound II is a 1D chain structure with the H3L- suspension arms. Complexes I and II are further extended into three-dimensional supramolecular framework via hydrogen bonds and π-π interactions. The solid state luminescent properties of compounds I and II have been investigated. [ABSTRACT FROM AUTHOR]

The g factors for Cu in meta-zeunerite (Cu(UO)(AsO)·3HO), kroehnkite (NaCu(SO)·2HO), copper benzoate (Cu(PhCO)·3HO) and diaboleite (PbCu(OH)Cl) of the tetragonal phase are uniformly treated by high order perturbation formulas for 3 d ions in tetragonally elongated octahedra. The calculation results are in good agreement with the observed values and systematically analyzed in view of the local structures around Cu. The g anisotropies Δ g (= g − g ) are largely ascribed to the local tetragonal elongations of the Cu sites, characterized by the relative elongation ratios ( R − R )/ R̅ ≈ 19%, 21%, 27% and 30% for metazeunertie, kroehnkite, copper benzoate and diaboletie, respectively. The anomalous valley (minimum) of relative g anisotropy for copper benzoate is attributed to the modification of the Cu electronic states due to the phenyl ring. The ligand orbital contributions are found to be significant due to covalency, and should be taken into account. The present study would be helpful to the unified investigations of structures and properties of the copper oxygen compounds. [ABSTRACT FROM AUTHOR]

The spin Hamiltonian parameters ( g factors, hyperfine structure constants and superhyperfine parameters) and local structures for Ag centers in AgCl and KCl crystals are theoretically studied using the high-order perturbation formulas for a tetragonally elongated 4 d cluster. The impurity centers undergo relative elongations (≈0.05 Å and 0.23 Å for Ag in AgCl and KCl, respectively) along the C axis owing to the Jahn-Teller effect. All the calculated spin Hamiltonian parameters show good agreement with the experimental data, and the ligand contributions to the spin Hamiltonian parameters are important and should be taken into account. The unpaired spin densities in the superhyperfine parameters are determined from molecular orbital coefficients based on the cluster approach, instead of being taken as the adjustable parameters in the previous treatments. Increasing tetragonal elongation from AgCl to KCl is attributed to a decrease in chemical bonding (or lower force constant) with increasing Ag-Cl distance. [ABSTRACT FROM AUTHOR]

In this work, we mainly study the magnification relations of quad lens models for cusp, fold and cross configurations. By dividing and ray-tracing in different image regions, we numerically derive the positions and magnifications of the four images for a point source lying inside of the astroid caustic. Then, based on the magnifications, we calculate the signed cusp and fold relations for the singular isothermal elliptical lenses. The signed fold relation map has positive and negative regions, and the positive region is usually larger than the negative region as has been confirmed before. It can also explain that for many observed fold image pairs, the fluxes of the Fermat minimum images are apt to be larger than those of the saddle images. We define a new quantity cross relation Rcross which describes the magnification discrepancy between two minimum images and two saddle images. Distance ratio dsadd/dmini is also defined as the ratio of the distance of two saddle images to that of two minimum images. We calculate the cross relations and distance ratios for nine observed Einstein crosses. In theory, for most of the quad lens models, the cross relations decrease as the distance ratios increase. In observation, the cross relations of the nine samples do not agree with the quad lens models very well, nevertheless, the cross relations of the nine samples do not give obvious evidence for anomalous flux ratio as the cusp and fold types do. Then, we discuss several reasons for the disagreement, and expect good consistencies for more precise observations and better lens models in the future. [ABSTRACT FROM AUTHOR]

Based on the perturbation treatments for a tetragonally distorted tetrahedral 3d cluster, the g factors and local angular distortions are calculated for ZnO:Cu nanocrystals with various Cu concentrations in different systems I and II under dissimilar experimental conditions. Because of the dynamic Jahn-Teller effect, the bond angles θ between the four equivalent Cu-O bonds and the C4 axis are about 1.5 larger than that (θ0 ≈ 54.736) of an ideal tetrahedron. Consequently, the original slightly trigonally distorted oxygen tetrahedron of the host Zn2+ site is transformed into a tetragonally compressed one. The isotropy of g factors may be attributed to the appropriate angular distortions Δθ = θ - θ due to the dynamic Jahn-Teller effect. The slightly increasing (or decreasing) g factors with concentration x can be illustrated as the delicate increases (or decreases) of the angular distortions (Δθ) and the covalency factors (N) for system I (or II), respectively, under almost equivalent crystal-fi eld strengths (Dq). [ABSTRACT FROM AUTHOR]

The electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants) for Cu in [Cu(ipt)(dap)HO]• nHO (ipt is isophthalic acid, dap-1,3-diaminopropane) are theoretically investigated from the high order perturbation formulas of these parameters for a 3 d ion in a rhombically elongated octahedron. The ligand orbital and spin-orbit coupling contributions are included from the cluster approach because of strong covalency of the system. The nearly axial anisotropies of the g factors and hyperfine structure constants are correlated to the significant elongation distortion of the five-fold coordinated Cu (in a distorted square pyramidal [CuNO] group). Nevertheless, the perpendicular anisotropies arising from the nonequivalent planar ligands are largely concealed by the experimental uncertainties. The theoretical analysis of the EPR behaviours for [Cu(ipt)(dap)HO]• nHO would be helpful to understand the local structures and properties of this and relevant systems. [ABSTRACT FROM AUTHOR]

We review five often used quad lens models, each of which has analytical solutions and can produce four images at most. Each lens model has two parameters, including one that describes the intensity of non-dimensional mass density, and the other one that describes the deviation from the circular lens. In our recent work, we have found that the cusp and the fold summations are not equal to 0, when a point source infinitely approaches a cusp or a fold from inner side of the caustic. Based on the magnification invariant theory, which states that the sum of signed magnifications of the total images of a given source is a constant, we calculate the cusp summations for the five lens models. We find that the cusp summations are always larger than 0 for source on the major cusps, while can be larger or smaller than 0 for source on the minor cusps. We also find that if these lenses tend to the circular lens, the major and minor cusp summations will have infinite values, and with positive and negative signs, respectively. The cusp summations do not change significantly if the sources are slightly deviated from the cusps. In addition, through the magnification invariants, we also derive the analytical signed cusp relations on the axes for three lens models. We find that both on the major and the minor axes the larger the lenses deviated from the circular lens, the larger the signed cusp relations. The major cusp relations are usually larger than the absolute minor cusp relations, but for some lens models with very large deviation from circular lens, the minor cusp relations can be larger than the major cusp relations. [ABSTRACT FROM AUTHOR]

In this study, the complete foxl2 complementary (c)DNA sequence was isolated by simple modular-architecture research tool (SMART)er rapid amplification of cDNA ends (RACE). Two year-old female spotted scat, Scatophagus argus, were reared at different temperatures (23, 26 and 29° C) for 6 weeks, or fed with different concentrations of dietary fish oil (0, 2 or 6%) for 8 weeks. Ovarian development, serum oestradiol-17β ( E2) levels, as well as ovarian foxl2 expression were measured. At the end of experiment, ovarian foxl2 messenger (m)RNA expression in fish reared at 23 and 26° C was significantly higher than that in fish reared at 29° C, and that in 2 and 6% fish oil groups was also significantly higher than that in control group ( P < 0·05). Serum E2 levels exhibited the same trend with foxl2 mRNA expression in temperature treatment groups and fish oil fed groups. There was a significant positive correlation between stage of oocytes and foxl2 expressions. Results showed that from 23 to 29° C, the optimal temperature for ovarian development in S. argus was 23-26° C, and 6% fish oil supplementation could effectively promote ovarian development. Optimal temperature and fish oil supplement might increase ovarian foxl2 mRNA expressions to promote ovarian development in S. argus. [ABSTRACT FROM AUTHOR]

The electron paramagnetic resonance parameters (i.e., g factor, hyperfine structure constant and superhyperfine parameters) of KMgF3:Cr+ are theoretically investigated from the perturbation formulae of these parameters for an octahedral 3d5 cluster. As for the calculations of g factor and hyperfine structure constant, both the contributions from the crystal-field and charge transfer mechanisms are included based on the cluster approach. The metal to ligand charge transfer contribution to the g-shift Δg (≈ g - 2:0023) is the same (negative) in sign and much larger in magnitude as compared to the crystal-field one. The conventional argument that the charge transfer contributions to zero-field splittings are negligible for 3d5 ions in fluorides is no longer suitable for Δg analysis of KMgF3:Cr+ due to the dominant second-order charge transfer perturbation term. The charge transfer contribution to hyperfine structure constant exhibits the same sign and about 4% of the crystal-field one. The unpaired spin densities of the fluorine 2s, 2pσ and 2pπ orbitals are quantitatively acquired from the relationships with the relevant molecular orbital coefficients using the uniform model. The present treatments are superior to the previous calculations of directly fitting the experimental superhyperfine parameters. [ABSTRACT FROM AUTHOR]

Fall nutrient loading of deciduous forest nursery seedlings is of special interest because of foliage abscission and varied translocation patterns. For non-deciduous seedlings in the nursery, fall fertilization typically can reverse nutrient dilution and possibly increase nutrient reserves; however, this technique has received little attention with deciduous conifer trees that translocate nutrients before abscising foliage. We evaluated how fall nitrogen (N) fertilization affected N storage and translocation in the deciduous conifer Olga Bay larch ( Larix olgensis Henry) seedlings during the hardening period. Seedlings were supplied with 25 mg N seedling −1 for 15 weeks before hardening and fall fertilization treatments began with a three week application period of K 15NO 3 at 0, 5, 10 and 15 mg N seedling −1. During the hardening period, fall N fertilization had little effect on seedling morphology. The N concentration and content of needles decreased dramatically as needles abscised, while that of stems and roots increased. Six weeks after fall N fertilization ceased, all seedlings translocated similar net N from their needles. For the control seedlings, this accounted for 84 % of the N stored in stems and roots. For fall fertilized seedlings, however, the proportion of N stored in stems and roots translocated from needles accounted for only 41–61 % of the total because of absorption of fall fertilizer that was translocated directly to stems and roots. Six weeks after fall fertilization, the distribution pattern of N concentration and content in seedlings was found in this order: stems > fine roots > coarse roots > needles. Our results suggest that providing deciduous conifer seedlings N during hardening, in this case Olga Bay larch, is a way to promote nutrient loading during nursery production. [ABSTRACT FROM AUTHOR]

An arbitrary surface mass density of the gravitational lens can be decomposed into multipole components. We simulate the ray tracing for the multipolar mass distribution of the generalized Singular Isothermal Sphere model based on deflection angles, which are analytically calculated. The magnification patterns in the source plane are then derived from an inverse shooting technique. As has been found, the caustics of odd mode lenses are composed of two overlapping layers for some lens models. When a point source traverses this kind of overlapping caustics, the image numbers change by ±4, rather than ±2. There are two kinds of caustic images. One is the critical curve and the other is the transition locus. It is found that the image number of the fold is exactly the average value of image numbers on two sides of the fold, while the image number of the cusp is equal to the smaller one. We also focus on the magnification patterns of the quadrupole (m = 2) lenses under the perturbations of m = 3, 4, and 5 mode components and found that one, two, and three butterfly or swallowtail singularities can be produced, respectively.With the increasing intensity of the high-order perturbations, the singularities grow up to bring sixfold image regions. If these perturbations are large enough to let two or three of the butterflies or swallowtails make contact, then eightfold or tenfold image regions can be produced as well. The possible astronomical applications are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Rapid urbanization leads to degradations upon water quality via eutrophication and pollution, but there are a lack of studies on patterns of water quality change to urbanization by level or process. China has achieved the most rapid urbanization in the world within the past three decades, and its urban development is diverse at level. Nine towns and cities at various development levels along the historic Grand Canal (approximately 1500 years old) were selected to reveal direct linkages between surface water quality and extent of urbanization. Surface water quality in the urban sections of the Grand Canal was impaired by both eutrophic nitrogen and phosphorus and metals. Although metals mostly remained at concentrations permissible to the Chinese National Environmental Standard for Surface Water Quality (GB3838-2002), the concentrations of metals in most urban canal water might impose an unacceptable effect on aquatic communities according to the Criterion Continuous Concentration from the National Recommended Water Quality Criteria for Priority Toxic Pollutants (US EPA 2006). The loadings of metals in the urban canal were found relating to local industrial activities. The level of urbanization, in this study, was significantly related to water quality parameters in a descending order of electrical conductivity > nutrients > metals. This study suggests that significant mitigation strategies are required for the Grand Canal of China for a sustainable urbanization goal. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

β-1,3-Glucan with 1.0 g kg−1 was supplemented to a basal diet [control (C)] with different feeding schedules: permanently β-1,3-glucan diet (BG) and 14 days BG-14 days control diet (C + BG). Growth and immunological responses [respiratory burst (RB), superoxide dismutase (SOD), catalase (CAT), lysozyme and total protein] in haemolymph, hepatopancreas and muscle of Litopenaeus vannamei were recorded after 84-day feeding and exposure to nitrite-N (20 mg L−1) for 120 h. β-1,3-Glucan administration did not affect growth performance. However, as compared with control, elevated CAT and lysozyme activities were seen in haemolymph of both BG groups, while significantly higher activities of SOD, lysozyme and RB in hepatopancreas, and higher activities of CAT and lysozyme in muscle were only seen in C + BG group. After nitrite-N stress, significantly higher haemolymph protein, and hepatopancreas activities of lysozyme and RB were observed in both BG groups, but significantly higher activities of haemolymph SOD was only seen in C + BG group. The mortality in groups BG and C + BG was significantly lower than that in group C, but C + BG group showed a trend of higher nitrite-N resistance compared with BG group. Considering dietary cost and immunostimulatory effects, the feeding schedule with 14 days BG-14 days control diet is more recommended. [ABSTRACT FROM AUTHOR]

T helper type 17 (Th17) and regulatory T cells (Treg) play an important role in the pathogenesis of inflammation and autoimmune disorders. Recent studies have suggested that they also had an impact on tumour immunology. However, the relationship between Th17 and Treg cells in the pathogenesis of bladder carcinoma is still unclear. Flow cytometry was used to analyse the numbers, phenotype and cytokine production of Th17 cells in peripheral blood and tumour tissue from bladder carcinoma patients, in parallel with analysis of Treg cells. The suppressor capacity of Treg and the potential effects of interleukin (IL)-2 on the differentiation of Th17 and Treg cells in vitro were studied in a T cell stimulation and suppression assays. The results were as follows: Th17 cells were enriched in the tumours of patients with bladder carcinoma compared with the peripheral blood of patients and controls; patients with bladder carcinoma had a higher proportion of Treg cells in peripheral blood compared with healthy controls and nearly all patients examined showed a relative enrichment of tumour-infiltrating Treg with respect to peripheral blood; there appeared to be an inverse relationship between tumour-infiltrating Th17 and Treg cells; IL-2 could convert tumour-infiltrating Treg cells cultured in the presence of the autologous irradiated CD3– fraction into Th17 cells, down-regulate forkhead box P2 expression and suppressive capacity of Treg cells. This study is the first to define the frequency and characteristics of Th17 cells in bladder carcinoma. We suggest that the balance between Th17 and Treg cells may be involved in the development or progression of bladder carcinoma. [ABSTRACT FROM AUTHOR]

Periodic flooding of trees in tropical floodplains and reservoirs where water levels fluctuate is a common phenomenon. The effects of flooding and subsequent recovery on gas exchange, chlorophyll fluorescence and growth responses of Melaleuca alternifolia seedlings, a tall shrub species used in floodplain and reservoir forest restoration in southern China, were studied during a grow season (from March to December in 2007). M. alternifolia seedlings were flooded for 180 days, drained and left to recover for another 60 days. Survival rates of the seedlings were 100% during the 180-day flooding period. Chlorophyll (Chl) content, net photosynthetic rate (PN), stomatal conductance (gs), and transpiration rate (E) of the flooded seedlings were all significantly lower than those of the control. Significant reductions of photochemical quenching coefficient (qp) and increases of nonphotochemical quenching (NPQ) in the flooded seedlings were observed. However, there were no significant differences in the maximal quantum yield of PSII photochemistry (Fv/Fm) between treatments. All seedlings survived during the two-month recovery period after the flooded treatment was drained, and the biomass and height of the recovered seedlings approached those of the control at the end of the experiment. During the first-month recovery period, Chl content, PN, gs and E in the recovered seedlings were all obviously low, then increased gradually and rose to the levels similar to the control by the end of the experiment. Quenching analysis revealed significant reductions of qp and increments of NPQ in the recovered seedlings at the beginning of draining, and a nearly complete recovery for both parameters by the end of the experiment. However, Fv/Fm of the recovered seedlings did not differ significantly from the control during the recovery period. Our study demonstrated that M. alternifolia seedlings can survive and grow through 180 days of flooding with a subsequent 60-day recovery period in drained conditions, indicating that seedlings of this species would be suitable for afforestation in areas exposed to intermittent flooding. [ABSTRACT FROM AUTHOR]

Aims: The objective of the present study was to verify the correlation of chromosomes 1p and 19q status and expressions of O6-methylguanine DNA methyltransferase (MGMT), p53 and Ki-67 in diffuse gliomas of World Health Organization grades II and III. Methods: A series of 146 diffuse gliomas, including 45 oligodendrogliomas, 42 oligoastrocytomas and 59 astrocytomas, were analysed by denaturing high-performance liquid chromatography for 1p and 19q status and by immunohistochemistry for MGMT, p53 and Ki-67 expression patterns. The molecular alterations were then correlated with clinicopathological characteristics and with each other. Results: Loss of heterozygosity (LOH) on 1p, combined LOH on 1p and 19q, low MGMT expression and high Ki-67 expression were associated with oligodendroglial tumours, whereas high p53 expression was associated with astrocytic and mixed tumours. LOH on 1p and low MGMT expression were associated with grade II oligodendroglial tumours, whereas high expressions of p53 and Ki-67 were associated with grade III oligodendroglial tumours. In addition, high Ki-67 expression was associated with grade III astrocytomas. LOH on 1p and LOH on 19q were associated with nontemporal oligodendroglial tumours. Nonrandom associations were found between LOH on 1p and LOH on 19q, MGMT expression and p53 expression, and MGMT expression and Ki-67 expression, whereas mutual exclusions were found between LOH on 1p and 19q and p53 expression, and LOH on 1p and Ki-67 expression. Conclusions: The present study revealed significant interrelationships of the investigated molecular alterations and clinicopathological characteristics in diffuse gliomas of World Health Organization grades II and III, which support a promising role of molecular markers in the diagnostic assessment of these neoplasms. [ABSTRACT FROM AUTHOR]

To improve the absorption and the bulk of arene ligands, two naphthoxy bounded ferrocenium salts as new cationic photoinitiators, (η6-α-naphthoxybenzene) (η5-cyclopentadienyl) iron hexafluorophosphate (NOFC-1) and (η6-β-naphthoxybenzene) (η5- cyclopentadienyl) iron hexafluorophosphate (NOFC-2), were synthesized, characterized, and studied. NOFC-1 and NOFC-2 were prepared by the reaction of nucleophilic substitution (SNAr) with naphthol and chlorobenzene-cyclopentadienyliron salt. Their activity as cationic photoinitiators was studied using real-time infrared spectroscopy. The results obtained showed that NOFC-1 and NOFC-2 are capable of photoinitiating the cationic polymerization of epoxy monomer directly on irradiation with long-wavelength UV light (365 nm). Comparative studies also demonstrated that they exhibited better efficiency than cyclopentadienyl-Fe-cymene hexafluorophosphate (I-261).When NOFC-1 and NOFC-2 were used to efficiently initiate polymerization of epoxide, both rate of polymerization and final conversion increased using benzoyl peroxide (BPO) as sensitizer. DSC studies showed that NOFC-1 and NOFC-2 photoinitiators in epoxides possess good thermal stability in the absence of light. [ABSTRACT FROM AUTHOR]

We use high-resolution N-body numerical simulations to study the number of predicted large-separation multiply imaged systems produced by clusters of galaxies in the Sloan Digital Sky Survey (SDSS) photometric and spectroscopic quasar samples. We incorporate the condensation of baryons at the centre of clusters by (artificially) adding a brightest cluster galaxy (BCG) as a truncated isothermal sphere. We make predictions in two flat cosmological models: a Λ cold dark matter (ΛCDM) model with a matter density and a model favoured by the Wilkinson Microwave Anisotropy Probe ( WMAP) three-year data with and ( WMAP3). We found that the predicted multiply imaged quasars with separation >10 arcsec is about 6.2 and 2.6 for the SDSS photometric (with an effective area of 8000 deg2) and spectroscopic (with an effective area of 5000 deg2) quasar samples, respectively, in the Λ CDM0 model; the predicted numbers of large-separation lensed quasars agree well with the observations. These numbers are reduced by a factor of 7 or more in the WMAP3 model, and are consistent with the data at ≲8 per cent level. The predicted cluster lens redshift peaks around redshift 0.5, and 90 per cent are between 0.2 and 1. The ratio of systems with at least four image systems and those with is about 1/3.5 for both the Λ CDM0 and the WMAP3 models, and for both the photometric and the spectroscopic quasar samples. We find that the BCG creates a central circular region, comparable to the Einstein ring of the BCG, where the central image disappears in the usual three- and five-image configurations. If we include four image systems as an extreme case of five-image systems (with an infinitely demagnified central image), we find that 68 per cent of the central images are fainter by a factor of 100 than the brightest image and about 80 per cent are within 1.5 arcsec of the BCG. [ABSTRACT FROM AUTHOR]

We use high-resolution N-body simulations to investigate the optical depth of giant arcs with length-to-width ratios larger than 7.5 and 10 in the ‘standard’Λ cold dark matter model with and and a model based on three-year Wilkinson Microwave Anisotropy Probe ( WMAP) data. We find that, in dark-matter-only simulations, the lensing probability in the three-year WMAP model (with and decreases by a factor of ∼6 compared with that in the ‘standard’Λ cold dark matter model. The effects of baryonic cooling, star formation and feedbacks are uncertain, but we argue that baryons will only increase the the lensing cross-section by a moderate factor, ∼2. We conclude that the low central value of σ8 and preferred by the WMAP three-year data may be too low to be compatible with observations if the conventional assumptions of the background source population are correct. [ABSTRACT FROM AUTHOR]

The nuclear effects in the neutrino–nucleus charged-current inelastic scattering process is studied by analyzing the CCFR and NuTeV data. The structure functions F2(x,Q2) and xF3(x,Q2) as well as differential cross sections are calculated by using CTEQ parton distribution functions and the EKRS and HKN nuclear parton distribution functions, and these are compared with the CCFR and NuTeV data. It is found that the corrections of the nuclear effect to the differential cross section for the charged-current antineutrino scattering on the nucleus are negligible, the EMC effect exists in the neutrino structure function F2(x,Q2) in the large x region, the shadowing and anti-shadowing effect occur in the distribution functions of valence quarks in the small and medium x region, respectively. It is also found that shadowing effects on F2(x,Q2) in the small x region in the neutrino–nucleus and the charged-lepton–nucleus deep inelastic scattering processes are different. It is clear that the neutrino–nucleus deep inelastic scattering data should further be employed in restricting the nuclear parton distributions. [ABSTRACT FROM AUTHOR]

The MPEG-4/AVC/H.264 video coding standard adopts various coding schemes such as multiple reference frames and variable block sizes for motion estimation. Hence, MPEG-4/AVC/H.264 provides gains in compression efficiency of up to 50% over a wide range of bit rates and video resolutions compared to previous standards. However, these features result in a considerable increase in encoder complexity, mainly regarding to mode decision and motion estimation. The proposed algorithms use the stored motion vectors to compose the motion vector without performing the full search in each reference frame. Therefore, the proposed algorithms can obtain an average speed up ratio of four for encoding, thus benefiting from the prediction of the motion vector for the reference frames in advance and maintaining good performance. Any fast search algorithm can be utilized to further largely reduce the computational load. [ABSTRACT FROM PUBLISHER]

Iontophoresis, a method that facilitates drug transport across skin by an external electrical field, offers the possibility for long-term transdermal delivery of compounds in a well-controlled manner. In general, the literature supports the contention that iontophoresis is a safe procedure. However, there are important medical issues concerning the epidermal and dermal effects of iontophoresis that have not been extensively investigated. Specific and strictly controlled studies on the dermal effect of iontophoresis are scarce. The aim of this study was to investigate the cutaneous side-effects of transdermal iontophoresis application in healthy human volunteers. This was a single-blinded, randomized and parallel design study. In one group ( n = 12) subjects were treated nonocclusively with a surfactant formulation followed by iontophoresis (3-h application at a current density of 250 µA cm−2). In another group ( n = 12) iontophoresis alone was performed. No drug was included in these studies. The corresponding passive treatments served as controls. Noninvasive methods including sensation record, transepidermal water loss (TEWL), skin colour and the visual scoring were used to assess cutaneous effects. Tingling and itching were commonly experienced in the first 30 min of the current application. Iontophoresis in combination with the pretreatment induced significant increases in TEWL values and in skin redness, and resulted in slight to mild erythema and oedema compared with the control. Compared with the iontophoresis alone, the presence of surfactant pretreatment caused slightly more skin irritation (erythema and oedema) but did not further disturb the skin barrier function. The transdermal iontophoresis challenges the skin barrier function and induces transient mild skin irritation, but does not cause any permanent damage to the skin when applied for 3 h at a current density of 0·25 mA cm−2. [ABSTRACT FROM AUTHOR]

The energy-loss effect in nuclear matter is another nuclear effect apart from the nuclear effects on the parton distribution as in deep inelastic scattering process. The quark energy loss can be measured best by the nuclear dependence of the high energy nuclear Drell-Yan process. By means of two typical kinds of quark energy-loss parametrization and the different sets of nuclear parton distribution functions, we present an analysis of the E866 experiments on the nuclear dependence of Drell-Yan lepton pair production resulting from the bombardment of Be, Fe and W targets by 800 GeV protons at Fermilab. It is found that the quark energy loss in cold nuclei is strongly dependent on the used nuclear parton distribution functions. The further prospects of using relatively low energy protons incident on nuclear targets are presented by combining the quark energy-loss rate determined from a fit to the E866 nuclear-dependent ratios versusx1, with the nuclear parton distribution functions given from lA deep inelastic scattering (DIS) data. The experimental study of the relatively low energy nuclear Drell-Yan process can give valuable insight in the energy loss of the fast quark propagating through cold nuclei and help to pin down nuclear parton distribution functions. [ABSTRACT FROM AUTHOR]

The energy loss effect in nuclear matter, which is a nuclear effect apart from the nuclear effect on the parton distribution as in deep-inelastic scattering process, can be measured best by the nuclear dependence of the high energy nuclear Drell-Yan process. By means of the nuclear parton distribution studied only with lepton deep-inelastic scattering experimental data, the measured Drell-Yan production cross sections for 800 GeV proton incident on a variety of nuclear targets are analyzed within the Glauber framework which takes into account the energy loss of the beam proton. It is shown that the theoretical results with considering the energy loss effect are in good agreement with the FNAL E866 data. [ABSTRACT FROM AUTHOR]