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Breast cancer is one of the tumors with the highest prevalence rate among women in the world, and its BRCA1/2 gene is a common mutation site. Talazoparib, as a targeted PARP inhibitor, can effectively control the occurrence and development of breast cancer with BRCA1/2 gene mutation, and play a therapeutic role. Based on the findings from the Phase III EMBRACE trial (NCT01945775 clinical trial), our analysis reveals that the talazoparib group demonstrated a significant extension in progression-free survival, along with improved response markers and patient-reported outcomes when compared to conventional therapies. This study aims to assess the cost-effectiveness of talazoparib for treating advanced breast cancer with germline BRCA1/2 mutations and HER2 negativity, considering the perspectives of health services in China and the United States. The results obtained will serve as a valuable reference for promoting rational drug utilization and enhancing medical resource efficiency. To evaluate the cost-effectiveness of Talazoparib more scientifically and provide clinicians with chemotherapy options, this paper developed a Markov model based on the EMBRACA clinical trial (clinical Trails.gov No., NCT01945775) to simulate the survival events of breast cancer patients in the Talazoparib group and the standard treatment group. The state transition probability and clinical data of breast cancer patients during treatment were extracted from the phase III EMBRACA clinical trial. The cost data generated during the treatment process comes from local hospital pricing, other references, and expert consultation. This article uses US dollars to calculate the treatment cost and incremental cost-effectiveness ratio. Health outcomes are expressed in Quality Adjusted Life Years (QALYs). In addition, Outcomes were measured in quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio, which robustness was evaluated by deterministic and probabilistic sensitivity analyses. This article establishes a Markov model for single-item sensitivity analysis. The results show that the economic benefits of using Talazoparib as a new treatment strategy in both China and the United States are higher than other drugs, and it is cost-effective. Compared to the control group, the incremental cost incurred by the Talazoparib treatment group in China was $2484.48/QALY, with an incremental QALY of 1.5. However, Talazoparib in the United States holds a dominant position, saving costs of $10,223.43 and increasing QALYs by 1.5. The clinical treatment effect of Talazoparib group in BRCA1/2 mutant advanced breast cancer patients is better than that of the standard treatment group, and the progression free survival period is significantly prolonged. From the perspective of medical and health services in China and the United States, the Talazoparib group is more economical than the standard treatment group in treating patients with BRCA1/2 mutant advanced breast cancer. [ABSTRACT FROM AUTHOR]

Background: The efficacy of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) is poor and great heterogeneity among individuals. Chemokines are highly correlated with tumor immune response. Here, we aimed to identify an effective chemokine for predicting the efficacy of immunotherapy in HCC. Methods: Chemokine C‐C motif ligand 21 (CCL21) was screened by transcriptomic analysis in tumor tissues from HCC patients with different responses to ICIs. The least absolute shrinkage and selection operator (LASSO) regression analysis was conducted to construct a predictive nomogram. Neutrophils in vitro and HCC subcutaneous tumor model in vivo were applied to explore the role of CCL21 on the tumor microenvironment (TME) of HCC. Results: Transcriptome analysis showed that CCL21 level was much higher in HCC patients with response to immunotherapy. The predictive nomogram was constructed and validated as a classifier. CCL21 could inhibit N2 neutrophil polarization by suppressing the activation of nuclear factor kappa B (NF-κB) pathway. In addition, CCL21 enhanced the therapeutic efficacy of ICIs. Conclusion: CCL21 may serve as a predictive biomarker for immunotherapy response in HCC patients. High levels of CCL21 in TME inhibit immunosuppressive polarization of neutrophils. CCL21 in combination with ICIs may offer a novel therapeutic strategy for HCC. [ABSTRACT FROM AUTHOR]

Intratumoral immune status influences tumor therapeutic response, but it remains largely unclear how the status determines therapies for patients with intrahepatic cholangiocarcinoma. Here, we examine the single-cell transcriptional and TCR profiles of 18 tumor tissues pre- and post- therapy of gemcitabine plus oxaliplatin, in combination with lenvatinib and anti-PD1 antibody for intrahepatic cholangiocarcinoma. We find that high CD8 GZMB+ and CD8 proliferating proportions and a low Macro CD5L+ proportion predict good response to the therapy. In patients with a poor response, the CD8 GZMB+ and CD8 proliferating proportions are increased, but the CD8 GZMK+ proportion is decreased after the therapy. Transition of CD8 proliferating and CD8 GZMB+ to CD8 GZMK+ facilitates good response to the therapy, while Macro CD5L+–CD8 GZMB+ crosstalk impairs the response by increasing CTLA4 in CD8 GZMB+. Anti-CTLA4 antibody reverses resistance of the therapy in intrahepatic cholangiocarcinoma. Our data provide a resource for predicting response of the combination therapy and highlight the importance of CD8+T-cell status conversion and exhaustion induced by Macro CD5L+ in influencing the response, suggesting future avenues for cancer treatment optimization. The role of the tumor microenvironment in immunotherapy response in intrahepatic cholangiocarcinoma remains unclear. Here, single cell RNA and TCR sequencing of samples before and after immunotherapy highlights the role of CD8 T-cell status conversion and exhaustion induced by Macro CD5L+ in treatment response. [ABSTRACT FROM AUTHOR]

Purpose: Positron emission tomography/magnetic resonance imaging (PET/MRI) is a powerful tool for brain imaging, but the spatial resolution of the PET scanners currently used for brain imaging can be further improved to enhance the quantitative accuracy of brain PET imaging. The purpose of this study is to develop an MR-compatible brain PET scanner that can simultaneously achieve a uniform high spatial resolution and high sensitivity by using dual-ended readout depth encoding detectors. Methods: The MR-compatible brain PET scanner, named SIAT bPET, consists of 224 dual-ended readout detectors. Each detector contains a 26 × 26 lutetium yttrium oxyorthosilicate (LYSO) crystal array of 1.4 × 1.4 × 20 mm3 crystal size read out by two 10 × 10 silicon photomultiplier (SiPM) arrays from both ends. The scanner has a detector ring diameter of 376.8 mm and an axial field of view (FOV) of 329 mm. The performance of the scanner including spatial resolution, sensitivity, count rate, scatter fraction, and image quality was measured. Imaging studies of phantoms and the brain of a volunteer were performed. The mutual interferences of the PET insert and the uMR790 3 T MRI scanner were measured, and simultaneous PET/MRI imaging of the brain of a volunteer was performed. Results: A spatial resolution of better than 1.5 mm with an average of 1.2 mm within the whole FOV was obtained. A sensitivity of 11.0% was achieved at the center FOV for an energy window of 350–750 keV. Except for the dedicated RF coil, which caused a ~ 30% reduction of the sensitivity of the PET scanner, the MRI sequences running had a negligible effect on the performance of the PET scanner. The reduction of the SNR and homogeneity of the MRI images was less than 2% as the PET scanner was inserted to the MRI scanner and powered-on. High quality PET and MRI images of a human brain were obtained from simultaneous PET/MRI scans. Conclusion: The SIAT bPET scanner achieved a spatial resolution and sensitivity better than all MR-compatible brain PET scanners developed up to date. It can be used either as a standalone brain PET scanner or a PET insert placed inside a commercial whole-body MRI scanner to perform simultaneous PET/MRI imaging. [ABSTRACT FROM AUTHOR]

Background: Relapse of hepatocellular carcinoma (HCC) due to vascular invasion is common, but the genomic mechanisms remain unclear, and molecular determinants of high-risk relapse cases are lacking. We aimed to reveal the evolutionary trajectory of microvascular invasion (MVI) and develop a predictive signature for relapse in HCC. Methods: Whole-exome sequencing was performed on tumor and peritumor tissues, portal vein tumor thrombus (PVTT), and circulating tumor DNA (ctDNA) to compare the genomic profiles between 5 HCC patients with MVI and 5 patients without MVI. We conducted an integrated analysis of exome and transcriptome to develop and validate a prognostic signature in two public cohorts and one cohort from Zhongshan Hospital, Fudan University. Results: Shared genomic landscapes and identical clonal origins among tumor, PVTT, and ctDNA were observed in MVI (+) HCC, suggesting that genomic changes favoring metastasis occur at the primary tumor stage and are inherited in metastatic lesions and ctDNA. There was no clonal relatedness between the primary tumor and ctDNA in MVI (–) HCC. HCC had dynamic mutation alterations during MVI and exhibited genetic heterogeneity between primary and metastatic tumors, which can be comprehensively reflected by ctDNA. A relapse-related gene signature named RGSHCC was developed based on the significantly mutated genes associated with MVI and shown to be a robust classifier of HCC relapse. Conclusions: We characterized the genomic alterations during HCC vascular invasion and revealed a previously undescribed evolution pattern of ctDNA in HCC. A novel multiomics-based signature was developed to identify high-risk relapse populations. [ABSTRACT FROM AUTHOR]

This paper is on determination of the thermal conductivities of several hydrocarbon base oils by means of non-equilibrium molecular dynamics simulations using two different force fields. It aims to explore a simulation-based method for lubricant molecular design and analysis concerning heat transfer in electrical vehicle lubrication. Argon was analyzed as a reference for method evaluation, and the results reveal that the calculated conductivity strongly depends on the size of the computational domain. However, for hydrocarbon base oils, the dependence on computation domain size is less prominent as the domain size increases. The method of direct calculation in a sufficiently large computation domain and that of reciprocal extrapolation with data calculated in a much smaller domain are both applicable, and each has a certain value in oil conductivity calculation. The calculated conductivities show certain overpredictions when compared with experimentally measured results, and the overprediction factor is related to number of carbon atoms of the liquid molecules. The results reveal that the thermal conductivity of a single-chain hydrocarbon liquid is linearly proportional to the number of carbon atoms. While each additional branch increases thermal conductivity slightly, the presence of multiple branches reduces it from the ideal linear relationship. A set of equations was formulated to correlate hydrocarbon liquid thermal conductivity with molecular characteristics in terms of number of carbon atoms and number of branches. [ABSTRACT FROM AUTHOR]

Multi-polymerization in which different polymerization mechanisms are performed together serves as an essential synthetic methodology for the construction of polymers with specific architectures, constitutions, and properties. Compared to single mechanism polymerization, the scope of multi-polymerization is significantly broadened by both the available synthetic methods and the synthesized polymeric materials. In this mini-review, multi-polymerizations are categorized into three major types based on the logical relationship between different mechanisms: sequential/tandem polymerization, orthogonal/concurrent polymerization, and hybrid polymerization. Each type of multi-polymerization is briefly introduced and summarized. This mini-review also discussed the importance of mutual influence in multi-polymerization and the potential research interests in this field. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic liver resection (LLR) has now been established as a safe and minimally invasive technique that is deemed feasible for treating hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). However, the role of LLR in treating combined hepatocellular-cholangiocarcinoma (cHCC-CC) patients has been rarely reported. This study aimed to assess the efficacy of LLR when compared with open liver resection (OLR) procedure for patients with cHCC-CC. Methods: A total of 229 cHCC-CC patients who underwent hepatic resection (34 LLR and 195 OLR patients) from January 2014 to December 2018 in Zhongshan Hospital, Fudan University were enrolled and underwent a 1:2 propensity score matching (PSM) analysis between the LLR and OLR groups to compare perioperative and oncologic outcomes. Overall survival (OS) and recurrence-free survival (RFS) parameters were assessed by the log-rank test and the sensitivity analysis. Results: A total of 34 LLR and 68 OLR patients were included after PSM analysis. The LLR group displayed a shorter postoperative hospital stay (6.61 vs. 8.26 days; p value < 0.001) when compared with the OLR group. No significant differences were observed in the postoperative complications' incidence or a negative surgical margin rate between the two groups (p value = 0.409 and p value = 1.000, respectively). The aspartate aminotransferase (AST), alanine aminotransferase (ALT), and inflammatory indicators in the LLR group were significantly lower than those in the OLR group on the first and third postoperative days. Additionally, OS and RFS were comparable in both the LLR and OLR groups (p value = 0.700 and p value = 0.780, respectively), and similar results were obtained by conducting a sensitivity analysis. Conclusion: LLR can impart less liver function damage, better inflammatory response attenuation contributing to a faster recovery, and parallel oncologic outcomes when compared with OLR. Therefore, LLR can be recommended as a safe and effective therapeutic modality for treating selected cHCC-CC patients, especially for those with small tumors in favorable location. [ABSTRACT FROM AUTHOR]

A series of polypeptoids with dual photo/thermo-responsiveness were prepared by incorporating both azobenzene (Azo) group and oligo(ethylene glycol) (OEG) segment into the side chains. Firstly, the N-substituted-N-carboxyanhydride (NNCA) monomers with different Azo and OEG groups were synthesized, and then a single NNCA ring-openning polymerization was performed to afford dual-responsive polypeptoids without any post-polymerization modification. The ultra-violet/visible (UV/Vis) photo-responsive behaviors of the polypeptoids were achieved by cis-trans photoisomerization of the Azo group and confirmed by both 1H-NMR and UV/Vis spectroscopy. The thermo-responsive behaviors were realized by both OEG segment and Azo group and confirmed by UV/Vis spectroscopy and dynamic light scattering. This work demonstrated the synthetic pathway for dual responsive polypeptoids using NNCA monomers with two responsive groups and revealed the potential of polypeptoids as smart materials that could respond to different environmental stimuli. [ABSTRACT FROM AUTHOR]

Three new mononuclear lanthanide complexes [Ln(2,4,6-TMBA)3(terpy)(H2O)]·C2H5OH·H2O (Ln = Gd(1), Er(2) and [Tb(2,4,6-TMBA)3(terpy)(H2O)]·C2H5OH(3) (2,4,6-TMBA = 2,4,6-trimethylbenzoate, terpy = 2,2′:6′,2′-terpyridine) were synthesized by solution evaporation method with 2,4,6-trimethylbenzoic acid and 2,2′:6′,2′-terpyridine. These new lanthanide complexes were characterized by elemental analysis, infrared spectroscopy, single-crystal X-ray diffraction, and thermal analysis. The title complexes were found to be mononuclear units with the same coordination number of nine. The structures of the three lanthanide complexes could be divided into two types. The difference was that there were not only free ethanol molecules but also free water molecules in complexes 1–2, while there were only free ethanol molecules in complex 3. Thermogravimetry (TG), differential thermogravimetric (DTG), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR) were used to study the thermal behavior of complexes and the gas escaping from the thermal decomposition process. In addition, the fluorescence test showed that complex 3 had strong green luminescence properties, and the fluorescence lifetime of complex 3 was 0.637 ms. [ABSTRACT FROM AUTHOR]

Three dinuclear lanthanide complexes were prepared using 2,6-dimethylbenzoic acid and 1,10-phenanthroline as main ligand and auxiliary ligand, namely: [Eu(2,6-DMBA)3(phen)]2(1), [Gd(2,6-DMBA)3(phen)]2·1.5H2O(2) and [Tb(2,6-DMBA)3(phen)]2·2.5H2O(3) (2,6-DMBA = 2,6-dimethylbenzoate; phen = 1,10-phenanthroline) and characterized by Raman spectroscopy, infrared spectroscopy, single crystal X-ray diffraction, elemental analysis and thermogravimetric analysis. Single-crystal X-ray diffraction shows that the three complexes were centered on 9 coordination Ln(III) ions and form a single hat tetragonal inverse prism geometry with surrounding nitrogen and oxygen atoms. The adjacent structural units form a 1D chain structure through C–H...O hydrogen bond interaction. TG-DSC/FTIR was used to study the thermal decomposition mechanism of the complexes and the main components of gases escaping during the decomposition process. Solid-state fluorescence studies showed that complexes 1 and 3 emitted strong red and green light, respectively. [ABSTRACT FROM AUTHOR]

Background: Most current whole-body positron emission tomography (PET) scanners use detectors with high timing resolution to measure the time-of-flight of two 511 keV photons, improving the signal-to-noise ratio of PET images. However, almost all current whole-body PET scanners use detectors without depth-encoding capability; therefore, their spatial resolution can be affected by the parallax effect. Methods: In this work, four depth-encoding detectors consisting of LYSO arrays with crystals of 2.98 × 2.98 × 20 mm3, 2.98 × 2.98 × 30 mm3, 1.95 × 1.95 × 20 mm3, and 1.95 × 1.95 × 30 mm3, respectively, were read at both ends, with 6 × 6 mm2 silicon photomultiplier (SiPM) pixels in a 4 × 4 array being used. The timing signals of the detectors were processed individually using an ultrafast NINO application-specific integrated circuit (ASIC) to obtain good timing resolution. The 16 energy signals of the SiPM array were read using a row and column summing circuit to obtain four position-encoding energy signals. Results: The four PET detectors provided good flood histograms in which all crystals could be clearly resolved, the crystal energy resolutions measured being 10.2, 12.1, 11.4 and 11.7% full width at half maximum (FWHM), at an average crystal depth of interaction (DOI) resolution of 3.5, 3.9, 2.7, and 3.0 mm, respectively. The depth dependence of the timing of each SiPM was measured and corrected, the timing of the two SiPMs being used as the timing of the dual-ended readout detector. The four detectors provided coincidence time resolutions of 180, 214, 239, and 263 ps, respectively. Conclusions: The timing resolution of the dual-ended readout PET detector was approximately 20% better than that of the single-ended readout detector using the same LYSO array, SiPM array, and readout electronics. The detectors developed in this work used long crystals with small cross-sections and provided good flood histograms, DOI, energy, and timing resolutions, suggesting that they could be used to develop whole-body PET scanners with high sensitivity, uniform high spatial resolution, and high timing resolution. [ABSTRACT FROM AUTHOR]

Polymerizations with multiple mechanisms performed simultaneously are promising but very challenging. As the key limitation, the complicated mutual influence between different mechanisms can be hardly defined and measured. Herein we establish a universal framework for the assessment of mutual influence between different mechanisms using binary polymerization for demonstration. The kinetics and thermodynamics of polymerization with two mechanisms are compared with the corresponding homopolymerization and the difference is expressed by a hybrid function. The hybrid function is composed of a hybrid parameter that describes the extent of mutual influence and a function that describes necessary conditions for mutual influence to occur. The extent of mutual influence can be calculated using kinetic and thermodynamic data without details of reaction mechanisms, for the first time providing a straightforward method to assess the mutual influence between different polymerization mechanisms. We envision that the method has potential in more complex systems with multiple mechanisms/monomers with mutual influence. [ABSTRACT FROM AUTHOR]

2-fluorobenzoic acid and 5,5′-dimethy-2,2′-bipyridine were used to construct two novel isostructural lanthanide complexes [Ln(2-FBA)3(5,5′-DM-2,2′-bipy)]2 (Ln = Eu(1), Tb(2); 2-FBA = 2-fluorobenzoate; 5,5′-DM-2,2′-bipy = 5,5′-dimethy-2,2′-bipyridine) by conventional solution method. They were characterized by infrared spectroscopy (IR), elemental analysis and single-crystal X-ray diffraction. The crystal description based on single-crystal X-ray diffraction data revealed that both of the complexes gave the triclinic crystal structure, belonging to the Pī space group. The two complexes were an infinite one-dimensional (1D) chain by hydrogen bonding (C–H...F) interactions to give a 2D supermolecular structure. Additionally, thermal behavior of the complexes was investigated by TG-DSC/FTIR technology in detail. The molar heat capacities of the two complexes in the temperature range of 278.15-423.15 K were determined by a DSC instrument, and their thermodynamic functions (HT-H298.15 K) and (ST-S298.15 K) were calculated. Beyond that, the fluorescence spectra and fluorescence lifetime of the complexes 1 and 2 were also evaluated. [ABSTRACT FROM AUTHOR]

It is of critical importance for our understanding of speciation process to determine the forms of reproductive isolation and their relative importance in species divergence. Oryza nivara and O. rufipogon are direct ancestors of Asian cultivated rice and a progenitor-daughter species pair. Investigating the reproductive isolation between them provides insights into plant speciation and helps understanding of the rice domestication. Here, we quantitatively measured the major components of reproductive isolation between the two species based on common garden and crossing experiments for three pairs of sympatric populations in Nepal, Cambodia and Laos. We revealed significant differences in the flowering times between species pairs, with O. nivara flowering much earlier than O. rufipogon. A very weak reduction in seed set but no reduction in F1 viability and fertility were detected for the crosses between species relative to those within species. Moreover, we detected asymmetrical compatibility between species and found that emasculation significantly decreased pollination success in O. nivara but not in O. rufipogon. Our study demonstrates that the divergence between O. nivara and O. rufipogon is maintained almost entirely by the difference in flowering times and suggests that differential flowering times contribute to both habitat preferences and reproductive isolation between species. [ABSTRACT FROM AUTHOR]

The growing role of precision medicine in hepatocellular carcinoma (HCC) is expected to ameliorate the poor prognosis and high mortality of this highly malignant disease; however, it is faced with challenges such as the low frequency of tissue biopsy. Hence, attention is turning to the circulating tumor DNA (ctDNA), an important component of liquid biopsy. Obtaining molecular information about cancer from blood provides a good prospect in precision oncology including molecular diagnosis, molecular classification, targeted therapy, personalized decision making, and detection of drug-resistance mutations. However, inherent constraints of HCC and ctDNA (like background chronic liver diseases (CLD) and low concentration of ctDNA) along with some technical issues should be well handled and solved before the potential of ctDNA in precision medicine of HCC can be truly realized. In this review, we will focus on the prospects and challenges of ctDNA in HCC precision medicine. [ABSTRACT FROM AUTHOR]

Two novel binuclear lanthanide complexes [Tb(2,3-DMOBA)3(5,5′-DM-2,2′-bipy)]2·C2H5OH (1) and [Dy(2,3-DMOBA)3(5,5′-DM-2,2′-bipy)]2·C2H5OH (2) (2,3-DMOBA = 2,3-dimethoxybenzoate, 5,5′-DM-2,2′-bipy = 5,5′-dimety-2,2′-bipyridine) have been successfully synthesized and structurally validated by single-crystal diffraction. The results of single-crystal analyses indicate the complexes contains one free ethanol molecule, and each center Ln(III) is nine-coordinated, exhibiting a distorted monocapped square anti-prismatic coordination geometry. The two center Ln(III) are bound by four 2,3-DMOBA ligands, two of which are bridging bidentate and the other two are bridging–chelating. The adjacent binuclear complexes can form 1D supramolecular structure by a pair of alternating identical C–H···O hydrogen bonding interactions, which further form 2D sheet structures. The thermal behavior of these complexes is investigated by TG-DSC/FTIR. What is more, the heat capacities of the complexes 1–2 are measured by DSC at 259.15–346.15 K, and the result indicates that the heat capacity values of the complexes gradually increased with the increase in temperature. In addition, the thermodynamic functions values (HT − H298.15K) and (ST − S298.15K) of the complexes 1–2 are calculated according to the fitted polynomial equations and the thermodynamic equation. The luminescence property of complex 1 is studied. [ABSTRACT FROM AUTHOR]

To improve the stability and performance of the cathode materials, an ionic conductor layer was coated successfully on the surface of Li1.2Mn0.54Ni0.13Co0.13O2 (LMNC) microspheres. The structural analysis confirmed that LiV3O8 coating did not change the basic structure of LMNC, and all obtained materials are solid solutions with a good-layered structure and a good crystallinity. The microscopy measurement showed that the thickness of the coating layer for the LV-3 sample is about 2.5 nm. This appropriate layer is helpful for improving the surface stability of LMNC and the diffusion of lithium, leading to an obvious enhancement of the electrochemical performance. Our result confirmed that the average discharge specific capacities for LV-3 sample at 0.1 C, 0.2 C, 0.5 C, 1 C, and 3 C are respectively 265.9, 219.1, 188.0, 156.3, and 121.5 mAh g−1, which are much larger than the values of other samples. After 50 cycles at a 1 C rate, the capacity retentions for different samples are 60.7%, 74.0%, 87.6%, and 70.4%, indicating that LV-3 sample exhibits the best performance. Furthermore, EIS measurements showed that the diffusion coefficient for LV-3 sample is calculated to be 1.26 × 10−15 cm2 s−1, which is also the largest value among all considered samples. Our experiments identified that coating an ionic conductive layer on the cathode material surface will significantly improve their rate capacity and cycling stability. [ABSTRACT FROM AUTHOR]

The combination of 3,4-dimethylbenzoic acid (3,4-DMHBA) and 5,5′-dimethyl-2,2′-bipyridine (5,5′-DM-2,2′-bipy) with rare earth nitrate under the room-temperature conditions results in two novel complex formulated as [Ho(3,4-DMBA)3(5,5′-DM-2,2′-bipy)(H2O)] (1) and [La(3,4-DMBA)3(3,4-DMHBA)(5,5′-DM-2,2′-bipy)]2(2), respectively. The structures were confirmed by single-crystal X-ray diffraction. Two complexes are all characterized with elemental analysis and PXRD. Interestingly enough, because of the lanthanide contraction phenomena, the complex 1 is a mononuclear molecule with the coordination number of eight, but the complex 2 is a binuclear molecule with the coordination number of nine. The thermal decomposition mechanism for two complexes was discussed by TG-DTG technology. In addition, the three-dimensional infrared accumulation spectra of the evolved gas during the thermal decomposition for title complexes were investigated via the simultaneous TG/DSC-FTIR techniques. Beyond that, the heat capacities of complexes were measured by DSC. And the smoothed value of heat capacities and thermodynamic functions (HT-H298.15) and (ST-S298.15) were calculated according to the fitted polynomial and thermodynamic equations. [ABSTRACT FROM AUTHOR]

Two trivalent rare earth compounds [Ln(3-MOBA)3(terpy)(H2O)]2 (Ln = Tb (1), Eu (2); 3-MOBA = 3-methoxybenzoate, terpy = 2,2′:6′,2″-terpyridine) were obtained in solid state, and the structure of 1 was determined by X-ray diffraction. The analysis of characterization was performed by elemental analysis, IR spectra, X-ray powder diffraction, thermogravimetric and differential scanning calorimetry coupled to infrared spectrometer (TG/DSC-FTIR). Besides that the luminescent properties and antibacterial activities were discussed. The crystal structure of 1 revealed that the asymmetric units were further stitched together to form 1D chain along the x-axis direction through the offset face-to-face π···π weak stacking interactions. Luminescence investigation revealed that compounds exhibited strong green and red emissions and the fluorescence quantum yield of two compounds were measured. What's more, the Commission Internationale de L'Eclairage chromaticity diagrams were presented. The antibacterial activity studies show that two compounds had good antibacterial actions on E. coli, S. aureus and no antibacterial activities on C. albicans. [ABSTRACT FROM AUTHOR]

The novel complex [Nd(3,4,5-TEOBA)3phen]2(3,4,5-TEOBA = 3,4,5-triethoxybenzoate; phen = 1,10-phenanthroline) has been synthesized and characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction, and thermogravimetry/differential scanning calorimetry-Fourier transform infrared (TG/DSC-FTIR) technology. Single-crystal X-ray diffraction data show the complex has two center metals, and each center is coordinated by seven oxygen atoms and two nitrogen atoms to form a distorted monocapped square antiprism geometry. The binuclear molecular skeleton connects together to form a 1D chain via stacking π-π interactions. The thermal decomposition mechanism of the title complex has been studied by TG/DSC-FTIR technology. The low-temperature heat capacity of the complex has been measured using a physical property measurement system in the temperature range from 1.9 to 300 K. The heat capacity was fitted to a series of theoretical and empirical models, and the thermodynamic functions were calculated based on the curve fitting. [ABSTRACT FROM AUTHOR]

Two new complexes [Tb(2,3-DClBA)3(5,5′-dmebipy)(H2O)]2 and [Er(2,3-DClBA)3(5,5′-dmebipy)(H2O)]2 (2,3-DClBA = 2,3-dichlorobenzoate; 5,5′-dmebipy = 5,5′-dimethylbipyridine) were prepared and characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, and TG/DSC technology. Single crystal X-ray diffraction data show that the two complexes are isomorphous. The complex is a binuclear molecular. Each Ln3+ center is coordinated by six oxygen atoms and two nitrogen atoms to form a distorted square antiprism geometry. The supramolecular architecture of the complex is constructed by H bond and halogen–halogen interactions. The thermal decomposition mechanism of the two complexes has been studied by TG/DSC technology. The low-temperature heat capacities of the complexes have been measured using a physical property measurement system in the temperature range from 10 to 302 K. The heat capacities were fitted to the polynomial equations by a least square method, and the thermodynamic functions were calculated based on the curve fitting. [ABSTRACT FROM AUTHOR]

Two lanthanide complexes [La(3,4-DMBA)3]n (1) and [Tb(3,4-DMBA)3(DIPY)2]2 (2) (where 3,4-DMBA = 3,4-dimethylbenzoate, DIPY = 2,2′-bipyridine) have been synthesized and then characterized. The single crystals of complexes 1 and 2 were obtained. Complex 1 adopts a distorted monocapped square antiprismatic molecular geometry, while complex 2 forms a distorted square antiprism. Complex 1 is stitched together by edge sharing through carboxylate ligands to form 1D chains along the b axis. The structure of complex 2 consists of 1D chains along the c axis by two kinds of π···π stacking interactions. Two complexes were characterized by elemental analysis, powder X-ray diffraction and IR spectra. The complex 2 shows typical green luminescence in the solid state. Thermal decomposition mechanisms of complexes were discussed by TG–DTG techniques. In the temperature range from 257.15 to 413.15 K, the molar heat capacities of the complexes were measured by DSC. The smoothed heat capacities and thermodynamic functions of complexes were calculated on the basis of fitted polynomial and thermodynamic equations. [ABSTRACT FROM AUTHOR]

Three novel ternary lanthanide complexes [Ln(2,5-DClBA)3(terpy)(H2O)] (Ln = Eu (1), Tb (2), Ho (3), 2,5-DClBA = 2,5-dichlorobenzoate, terpy = 2,2:6′,2″-terpyridine) have been successfully synthesized and characterized by single-crystal and powder X-ray diffraction. Complexes 1–3 are isostructural, and each metal center is nine-coordinated with distorted monocapped square antiprismatic coordination geometry. The mononuclear units are assembled into 1D, 2D, 3D supramolecular structures by the π–π stacking and halogen–halogen interactions. Thermal decomposition mechanisms of the title complexes were investigated by thermogravimetric analysis and further authenticated by TG/DSC-FTIR techniques. The solid-state fluorescent properties of complexes 1–2 were studied at room temperature, and characteristic emission was observed for all complexes. Complex 1 exhibits the strong red emission, while the complex 2 is green under UV light. Moreover, the antibacterial activities of the complexes against Candida albicans, Escherichia coli and Staphylococcus aureus were also evaluated. [ABSTRACT FROM AUTHOR]

Two new lanthanide complexes [Tb(3,4,-DEOBA) 5,5′-DME-2,2′-BIPY] (1), [Dy(3,4,-DEOBA)5,5′-DME-2,2′-BIPY] (2)(3,4,-DEOBA=3,4-diethoxybenzoate,5,5′-DME-2,2′-BIPY=5,5′-dimethy-2,2′-bipyridine) have been synthesized and characterized by elemental analysis, IR spectra and powder X-ray diffraction. The single crystal of the complex 1 has been obtained. There are two kinds of coordination modes in complex, 1 and the Tb ion is eight-coordinated. The luminescence spectra of complexes 1 and 2 show the characteristic emission of Tb ion (D → F) and Dy ion (F → H,H). The results of thermal decomposition mechanism of the title complexes show that two complexes are thermally stable. And the pathway of thermal decomposition has been investigated by the coupled TG-FTIR technique. In the thermal decomposition of the title complexes, neutral ligands lose firstly, and then 3,4-DEOBA decompose into gaseous molecules of HO and CO. The kinetics of the first decomposition stage for two complexes are investigated by using the integral isoconversional nonlinear (NL-INT) method, which suggests that the first decomposition step of two complexes is complex reactions. The heat capacities of title complexes were measured by DSC in the temperature range from 258.15 to 343.15 K. The smoothed heat capacities and thermodynamic functions of the complexes are calculated based on the fitted polynomial and thermodynamic equations. The antibacterial performance study of complexes shows that two complexes have good antibacterial activity against Candida albicans, Staphylococcus aureus and no bacteriostatic activity on Escherichia coli. [ABSTRACT FROM AUTHOR]

Two novel mononuclear lanthanide complexes, [Ln(2,4-DClBA)(terpy)(HO)]·HO (Ln = Dy(1), Er(2)); 2,4-DClBA: 2,4-dichlorobenzoate; terpy: 2,2′:6′,2″-terpyridine; have been synthesized and characterized by single-crystal and powder X-ray diffraction. The results reveal that complexes 1-2 are isomorphous, and each Ln ion is nine coordinated adopting a distorted monocapped square antiprismatic molecular geometry. Mononuclear complexes 1-2 are stitched together via Cl- π and hydrogen bonding interactions to form the 1D, 2D, 3D supramolecular structures, which the 3D is rarely observed. Thermal decomposition mechanism is determined by TG/DSC-FTIR, and the 3D stacked plots for the FTIR spectra of the evolved gases were recorded. Heat capacities of complexes 1-2 were measured, and the derived thermodynamic functions ( H − H ), ( S − S ) and ( G − G ) of the complexes relative to the standard reference temperature 298.15 K were obtained. The activation energy E values of the first decomposition stage for title complexes were calculated by integral isoconversional nonlinear (NL-INT) and Starink methods. Complex 1 shows the characteristic emission of Dy with strong yellow emission. [ABSTRACT FROM AUTHOR]

With the development of technology and space exploration, studies on long-duration space flights have shown that microgravity induces damage to multiple organs, including the dorsal root ganglia (DRG). However, very little is known about the effects of long-term microgravity on DRG neurons. This study investigated the effects of microgravity on lumbar 5 (L5) DRG neurons in rats using the hindlimb unweighting (HU) model. Male (M) and female (F) Sprague-Dawley rats were randomly divided into M- and F-control (CON) groups and M- and F-HU groups, respectively (n = 10). At the end of HU treatment for 4 weeks, morphological changes were detected. Myelin basic protein (MBP) and degenerated myelin basic protein (dgen-MBP) expressions were analyzed by immunofluorescence and western blot assays. Glial cell line-derived neurotrophic factor (GDNF) protein and mRNA expressions were also analyzed by immunohistochemistry, western blot, and RT-PCR analysis, respectively. Compared with the corresponding CON groups, the HU groups exhibited slightly loose junctions between DRG neurons, some separated ganglion cells and satellite cells, and lightly stained Nissl bodies that were of smaller size and had a scattered distribution. High levels of dgen-MBP and low MBP expressions were appeared and GDNF expressions were significantly decreased in both HU groups. Changes were more pronounced in the F-HU group than in the M-HU group. In conclusion, HU treatment induced damage of L5 DRG neurons, which was correlated with decreased total MBP protein expression, increased dgen-MBP expression, and reduced GDNF protein and mRNA expression. Importantly, these changes were more severe in F-HU rats compared with M-HU rats. [ABSTRACT FROM AUTHOR]

G2 and S phase-expressed-1 (GTSE1) was recently reported to upregulate in several types of human cancer, based on negatively regulate p53 expression. However, its expression and functional roles in hepatocellular carcinoma (HCC) remain unknown. In this study, GTSE1 was observed to be highly expressed in HCC specimens and cell lines both at messenger RNA (mRNA) and protein levels. Furthermore, high GTSE1 expression was positively associated with tumor size, venous invasion, advanced tumor stage, and short overall survival. Moreover, we generated stable GTSE1 knockdown HCC cell lines to explore the effects of GTSE1 silencing on the growth and invasion of HCC in vitro. In determining the pathway through which GTSE1 regulated cell proliferation and invasion, GTSE1 silencing was found to inhibit AKT phosphorylation and downregulated cell cycle-related protein. In addition, GTSE1 downregulation decreased the growth of xenografts. In conclusion, these results indicated for the first time that overexpression of GTSE1 was involved in the progress of HCC, enhancing proliferation and promoting cell invasion in HCC cells. [ABSTRACT FROM AUTHOR]

Four new lanthanide 4-ethylbenzoic acid complexes [Ln(4-EBA)(terpy)HO] {Ln = Sm(1), Eu(2), Tb(3), Dy(4), 4-EBA = 4-ethylbenzoate, terpy = 2,2′:6′,2′′-terpyridine} have been synthesized. The complexes are characterized by means of elemental analysis, IR, UV, and XRD. The crystals [Ln(4-EBA)(terpy)HO] {Ln = Eu(2), Tb(3)} are characterized by single-crystal X-ray diffraction. These complexes feature a tridentate terpyridine ligand, 4-ethylbenzoic acid ligands exhibiting multiple binding modes, bidentate, bridging bidentata, and monodentate, and a bound water molecule. The Ln ions have a typical coordination number of nine with a distorted monocapped square antiprism. The thermal decomposition mechanism of the complexes has been investigated by TG/DSC-FTIR technology, and IR spectra of the evolved gases show complexes broken down into HO, CO, and other gaseous molecules as well as the gaseous organic fragments. Moreover, the complexes [Ln(4-EBA)(terpy)HO] exhibit characteristic luminescence, indicating that ligands can act as sensitizing chromophore in these systems. [ABSTRACT FROM AUTHOR]

The crystal structures of complexes [Tb(3-Br-4-MBA)phen]( 1), [Ho(3-Br-4-MBA)(phen)HO]( 2) and [Er(3-Br-4-MBA)(phen)HO]( 3) (3-Br-4-MBA=3-bromine-4-methylbenzoate, phen=1,10-phenanthroline) have been solved by single-crystal X-ray diffraction methods. All obtained products were examined and characterized by elemental analysis, molar conductivity, IR, UV and XRD techniques. The thermogravimetric analysis of 1 to 3 was studied, indicating that the decomposition processes of 2 and 3 are different from 1. The mass loss of the first step for 2 and 3 is attributed to the HO molecules. The three-dimensional IR accumulation spectra of gaseous of 1 to 3 were also recorded. Complex 1 emits strong and bright green fluorescence under UV light at the room temperature. The bacteriostatic activities of the three complexes against bacteria, such as Escherichia coli and Staphylococcus aureus, and fungus (Candida albicans) were tested. [ABSTRACT FROM AUTHOR]

The pressure-viscosity coefficient (the α value), which represents the variation of viscosity as a function of pressure, is an important parameter for elastohydrodynamic lubrication analyses. The properties of hydrocarbons in the C-C mass range are of fundamental importance as they are basic constituents of synthetic- and mineral-based lubricant stocks. The conventional acquisition of the α value requires preparation of lubricant samples and experimental testing by means of a high-pressure viscometer. In this paper, we present a method to obtain the α value of a typical base oil (1-Decene trimer) based solely on the molecular dynamics simulations. Non-equilibrium molecular dynamics (NEMD) simulations were performed to calculate the shear viscosity of the lubricant at various temperatures and pressures up to 1 GPa. Elevated temperatures and time-temperature superposition (TTS)-based extrapolations were applied to further extend the ability of the NEMD simulations, and the rotational relaxation time was calculated and used to determine the validity of the NEMD calculations. The α value at 100 °C was calculated and compared with experimental results. Effectiveness of the extrapolation was evaluated with a 95 % confidence interval. [ABSTRACT FROM AUTHOR]

Two lanthanide complexes with the formula [Dy(3-Cl-4-MOBA)phen] (1) and [Eu (3-Cl-4-MOBA)phen] (2) (3-Cl-4-MOBA=3-chloro-4-methoxybenzoate; phen=1,10-phenanthroline) were synthesized and characterized by elemental analysis, molar conductivity, ultraviolet spectra, infrared spectra, single crystal X-ray diffraction, and thermal analysis. The two complexes are isostructural. Two lanthanide cations are connected by four carboxylic groups through a bridging bidentate mode, resulting in distorted square-antiprism geometry. Under the excitation ultraviolet light, the two complexes exhibit characteristic emission of dysprosium or europium cation. The gaseous decomposition products of the two complexes were inferred by thermogravimetry and infrared spectrometry techniques. The heat capacity of the complexes was measured using differential scanning calorimetry technology. And the thermodynamic functions including entropy, gibbs free energy, and enthalpy relative to the reference temperature (298.15 K) were also calculated. In addition, the antifungal activities of the two complexes were also studied. [ABSTRACT FROM AUTHOR]

Five new binuclear lanthanide compounds [Ln(2,4-DClBA)phen] (Ln = Pr( 1), Eu( 2), Tb( 3), Ho( 4) and Er( 5); 2,4-DClBA = 2,4-dichlorobenzoate; phen = 1,10-phenanthroline) have been synthesized and structurally characterized by X-ray crystallography. And all of them were carefully investigated by elemental analysis, molar conductance, IR, UV and TG/DSC-FTIR technology. Single-crystal X-ray diffraction studies revealed that compounds 1- 5 were binuclear molecules with an inversion center and the Ln ions contained two kinds of coordination environment that was a distorted monocapped square-antiprism in the compounds 1- 2, and a distorted square-antiprism geometry in the compounds 3- 5. The 3D surface graphs for the FTIR spectra of gaseous products for the compounds 1- 5 were recorded using simultaneous TG/DSC-FTIR technique which is intended to further analysis of the thermal decomposition processes. Hence the gaseous products were identified by the solved single IR spectra obtained at different temperatures from the 3D surface graphs. Furthermore, the Eu(III) and Tb(III) ternary compounds exhibited intense luminescence under the radiation of UV light. And the results for antimicrobial test show that these compounds exhibit good bacteriostatic activity against Staphylococcus aureus, and better antimicrobial activity against Escherichia coli and Candida albicans. [ABSTRACT FROM AUTHOR]

A methodology is presented for the evaluation of smoke damage contours through the coupling of smoke damage functions, deposition profiles and damage thresholds. Previously developed smoke damage functions and deposition velocities are used to illustrate 'far-field' smoke damage potentials both for materials representative of semiconductor fabrication facilities as well as large warehouse storage applications. For semiconductor fabrication, smoke damage associated with leakage current (LC) is important, while smoke staining is of primary interest in warehouse storage. Smoke deposition velocities, a key component to quantifying smoke deposition profiles, were determined in a small (1.0 m) and large (1,200 m) enclosure. Both enclosures resulted in comparable values. The velocities ranged from 1.2 to 7.3 × 10 m/s. To determine smoke damage potential contours for semiconductor fabrication facilities, electronic circuit board targets were used. Smoke damage was quantified by LC (i.e., shorting). The average normalized LC values for polyvinylchloride, polycarbonate, and nylon ranged from 0.72 to 6.1 × 10 A m/g. For warehouse storage facilities, filter targets were used. Smoke damage was quantified by brightness change and odor (i.e., volatile organic compounds, VOC) measurements on the targets. Representative materials were liner board, polystyrene, and polymethyl methacrylate. The smoke damage threshold value for brightness change was 0.012 g/m and for odor was 0.025 g VOC/m. Resulting contours showed strong radial dependency with distance from the fire/smoke source. Smoke damage reached ~28 m for semiconductor fabrication facilities, while for warehouse storage facilities, it was up to 100 m. [ABSTRACT FROM AUTHOR]

A series of lanthanide complexes [Ln(4-Cl-2-MOBA)phen] (Ln=Sm ( 1), Nd ( 2), Ho ( 3), Eu ( 4), Dy ( 5), and Tb ( 6); 4-Cl-2-MOBA=4-chloro-2-methoxybenzoate, phen=1,10-phenanthroline) were synthesized and characterized. The single-crystal X-ray diffraction demonstrates that 1- 3 are isomorphous, which present dimeric structures with four 4-Cl-2-MOBA anions function as bridging ligands. Complexes 1 and 4- 6 display their characteristic luminescence emission bands of central Ln ions. The heat capacities, the thermodynamic functions and the thermogravimetry-Fourier transform infrared spectra of gaseous products of complexes 1- 6 were investigated. Their non-isothermal kinetics of the second decomposition stage was studied by the integral isoconversional non-linear method and Stark method. Furthermore, 1- 6 exhibited excellent antibacterial activity against Candida albicans, Escherichia coli and Staphylococcus aureu. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most serious health problems worldwide. As in many other diseases, environment and genetic factors are believed to be involved in the pathogenesis of HCC. Numerous epidemiologic investigations including case-control and cohort studies have suggested the association of glutathione S-transferase ( GST) genetic polymorphisms and HCC risk. However, some studies have produced conflicting results. Therefore, we performed an updated meta-analysis to clarify this inconsistency and to establish a comprehensive picture of the association of the polymorphisms of GSTM1 and GSTT1 with HCC susceptibility. We searched PubMed, Embase, ISI Web of Science, and CNKI databases to identify eligible studies meeting the inclusion criteria up to August 30, 2013. Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the strength of association. Finally, there were a total of 33 studies with 4,232 cases and 6,601 controls included in this meta-analysis. In the pooled analysis, significantly increased HCC risks were found for null genotype of GSTM1 (OR = 1.31, 95 % CI = 1.07-1.61, P = 0.010, P < 10) and GSTT1 (OR = 1.47, 95 % CI = 1.25-1.74, P < 10, P < 10). Potential sources of heterogeneity were explored by subgroup analysis based on ethnicity, sample size, and source of control. Significant results were found among East Asians and Indians when stratified by ethnicity, while no evidence of significant associations was observed among Caucasian and African populations. In the gene-gene interaction analysis, a statistically significant increased risk for HCC was detected for individuals with combined deletion mutations in both genes compared to those with wild genotypes (OR = 1.88, 95 % CI = 1.41-2.50, P < 10, P = 0.004). The present meta-analysis demonstrated that the GSTM1 and GSTT1 null genotype may be associated with an increased risk of HCC and that individuals having the combination of both defective GST genotypes may be more susceptible to developing HCC. [ABSTRACT FROM AUTHOR]

Background: Crosstalk between a tumor and the microenvironment plays a key role in tumor progression and metastasis. This study was performed to elucidate the prognostic significance of combining tumor-secreted osteopontin (OPN) with microenvironment-associated peritumoral macrophages (PTMs) in hepatocellular carcinoma (HCC), especially for those with early-stage disease. Methods: Tissue microarray-based immunohistochemistry was used to investigate OPN and PTMs expression in two independent cohorts consisting of 374 patients with HCC who underwent radical resection. The prognostic value for the two factors alone or in combination was investigated in these patients. Results: OPN combined with PTMs was an independent prognostic factor for both overall survival (OS; p < 0.0001) and time to recurrence (TTR; p = 0.003) from the learning cohort ( n = 96). Their combined value for prognosis was validated in early-stage HCCs using another independent cohort ( n = 278; OS, p < 0.001; TTR, p = 0.001). This combination remained significant in HCCs with low α-fetoprotein levels in both cohorts, and was predictive for early recurrence/death risk (<2 years) compared with a single marker. Only OPN+HCCs had a significant correlation of PTMs levels with OS ( p = 0.01) or TTR ( p = 0.011). Conclusions: Tumor OPN combined with PTMs is a promising predictor of tumor recurrence and survival in patients with HCC, especially for those with early-stage disease. The interplay of OPN and PTMs represents a new insight into tumor progression and therapeutic targets for HCC. [ABSTRACT FROM AUTHOR]

The binding energy, dissociation energy, ionization potentials, electron affinities, gap and stability of small AlPt ( n = 1-15) clusters, in comparison with pure aluminum clusters have been systematically investigated by means of density functional calculations at the B3LYP level. The growth patten for AlPt clusters is that the Pt atom substituted the surface atom of the Al clusters for n < 13. Starting from n = 13, the Pt atom completely falls into the center of the Al-frame. The Pt atom substituted the center atom of the Al clusters to form the Pt-encapsulated Aln geometries for n > 13. We also find that the impurity Pt atom causes local structural distortion due to different atomic radii and different bonding characteristics. The clusters with total atom numbers of 2, 7, and 11 exhibit high stability. [ABSTRACT FROM AUTHOR]

The weld profiles, weld width, weld positions, and mechanical property changes in the weld and heat-affected zones (HAZ) are the most important parameters that influence the potential formability of the welded tube. To investigate the effect of weld characteristics on the forming behaviors of the welded tube, finite element models which consider the geometric profile and mechanical properties of the weld and HAZ are employed. The results show that (1) the mechanical constitutive relation of the weld region determined by the microhardness empirical formula obviously decreases the tangent strain, thickness strain, and cross-sectional deformation ΔD in the weld and HAZ as compared with that determined by the improved rule of mixtures, which is contrary to the hoop strain, and the predicted results determined by the improved rule of mixtures are much closer to the experimental ones; (2) different weld and HAZ widths determined by the microhardness profile and metallographic section have a little effect on the tangent strain, thickness strain, and ΔD distribution; (3) the implementation of weld profile and material properties decreases the wall variation of the weld region as the weld line locates on the outside and inside. On the contrary, both the weld profile and weld material properties increase the maximum ΔD. The sectorial weld profile has a stronger effect on the wall variation and maximum ΔD than the hourglass profile; and (4) the same weld and HAZ volume have a stronger effect on wall thinning and Δ D. [ABSTRACT FROM AUTHOR]

To understand the reason of defects and the basic mechanics involved in the welded tube numerical control bending process, it is important to study the effects of the weld and processing parameters on the strain distributions of the tube. The grid method that combines with vision-based surface strain measurement system GMASystem is used to research the strain distributions of the bent tube experimentally. The results show that the weld has a limited effect on the strain evolution as the weld is not located in the region of locally highest strains. As the weld line locates on the outside, the maximum tangent and thickness strain decrease by 0.94 and 8.78 %, while the maximum hoop strain increases by 22.15 % as compared with that the weld line locates on the middle. As the weld line locates on the outside and inside, the thickness strain decreases obviously in the weld region. The variation of thickness strain is little with smaller mandrel extension length, and the maximum thickness strain increases by 21.38 % as the extension length changes from 6 to 10 mm. The thickness strain decreases with larger push assistant level. The maximum thickness strain increases with larger bending angle. [ABSTRACT FROM AUTHOR]

This paper describes syntheses and structure determination of four lanthanide complexes [Nd(2-Cl-4-FBA)phen] ( 1, 2-Cl-4-FBA = 2-chloro-4-fluorobenzoate, phen = 1,10-phenanthroline), [Ln(2,5-DClBA)phen] (Ln = Sm( 2) and Tb( 3), 2,5-DClBA = 2,5-dichlorobenzoate) and [Sm(2-Cl-4,5-DFBA)(phen)(HO)] ( 4, (2-Cl-4,5-DFBA = 2-chloro-4,5-difluorobenzoate). The complexes were characterized by elemental analysis, infrared and ultraviolet spectra, and X-ray single-crystal diffraction. In the molecular structures of 1-4, two Ln ions are linked by four carboxyl groups, with two of them in a bridging bidentate mode and the other two in a bridging-chelating tridentate mode, forming four binuclear molecules. In addition, each Ln ion is also chelated to one phen molecule and one carboxyl group in the complexes, except each Sm ion in 4 which is bonded to one carboxyl group by unidentate mode and one HO molecule. There are two different coordination polyhedrons for each Nd ion in the two similar molecular structures of 1 and they are a distorted monocapped square antiprismatic and a distorted tricapped triangular prism conformation, respectively. The coordination polyhedron for each Ln ion in 2-4 is a nine-coordinated distorted mono-capped square antiprismatic conformation. The complex 3 exhibits green luminescence under the radiation of UV light. The thermal decomposition behaviors of the complexes have been discussed by simultaneous TG/DSC-FTIR technique. The 3D surface graphs for the FTIR spectra of the evolved gases were recorded and the gaseous products were identified by the typical IR spectra obtained at different temperatures from the 3D surface graphs. Meanwhile, we discussed the non-isothermal kinetics of 1-4 by the integral isoconversional non-linear (NL-INT) method. [ABSTRACT FROM AUTHOR]

For a low carbon steel tube with small wall factor D/t and bending radius R, the over-thinning induced localized necking is one dominant failure in tube numerical control (NC) bending process, which strongly restricts the bendability limit of the tube. In addition, the deterioration of bendability of a tube is increased by the existence of the weak weld region. Therefore, an important issue is how to determinate and predict the welded tube bendability limit. In the present study, a finite element (FE) model with weld and subdivided heat affected zones under ABAQUS platform is employed to explore the deformation behaviors of welded tube NC bending. A localized necking criterion based on the critical thickness thinning is used to predict the critical principal strains, critical bending radius and burst location during the forming process. It is found that the failures always occur at the rigid supporting point of mandrel flexible balls near the tangent point at the outside of the bend, where the wall thickness of the tube is the lowest. The bending limit curves (BLCs) of the QSTE340 welded tube are obtained by shifting the standard shaped forming limit curve to the critical principal strains along the major strain axis. Comparison between the numerical and experimental results has shown that the BLC and critical bending radius predictions agree well with the experimental results. In addition, the effect of weld positions on BLC is discussed, the weld region shows an almost negligible effect on the forming limit at a non-critical location that is far away from the outside of the bend. However, when the weld is at the large tensile deformation region on the outside of the bend, a decrease of the forming limit strains is seen. [ABSTRACT FROM AUTHOR]

A series of lanthanide complexes with the 3,4,5-trimethoxybenzoic acid (3,4,5-tmoba) and 1,10-phenanthroline(phen), [Ln(3,4,5-tmoba)phen](Ln = Pr(1), Nd (2) and Ho(3)), have been synthesized and characterized by a series of techniques including elemental analysis, IR spectra, X-ray crystallography and TG/DSC-FTIR technology. The three complexes have two kinds of coordination modes, in which the Pr and Nd cations are nine-coordinated and the Ho cation is eight-coordinated. The three-dimensional IR accumulation spectra of gaseous products for complexes 1-3 were analyzed and the gaseous products were identified by the typical IR spectra obtained from the 3D surface graphs. Meanwhile, we obtained the activation energy E of the first steps of complexes 1-3 by the integral isoconversional non-linear (NL-INT) method and discussed the non-isothermal kinetics of complexes 1-3 using the Malek method. Finally, SB( m, n) was defined as the kinetic method of the first-step thermal decomposition. The thermodynamic parameters Δ G, Δ H and Δ S of activation at the peak temperature were also calculated. [ABSTRACT FROM AUTHOR]

Some binuclear lanthanide complexes with the general formula [Ln(2,3-DClBA)bipy] (Ln = Sm( 1), Eu( 2), Tb( 3), Dy( 4), and Ho( 5); 2,3-DClBA = 2,3-dichlorobenzoate; bipy = 2,2′-bipyridine) were synthesized and characterized by elemental analysis, molar conductance, infrared, ultraviolet, luminescent spectroscopy, thermogravimetry, and different thermogravimetry (TG-DTG) techniques. The single crystals of the complexes have been obtained except the complex 2 and their structures have been determined by single-crystal X-ray diffraction. The four complexes are isostructural and the rare earth ions are all nine coordinated. The two rare earth ions in each complex are linked by two bridging bidentate and two chelating-bridging tridentate carboxylate groups. Under ultraviolet light excitation, the europium and terbium complexes exhibited characteristic red fluorescence of Eu ion and green fluorescence of Tb ion at room temperature. The non-isothermal kinetics was investigated by using the integral isoconversional non-linear (NL-INT) and the Popescu methods. The mechanism functions of the first decomposition step of the complexes 3- 5 were determined. Meanwhile, the thermodynamic parameters (Δ G , Δ H, and Δ S) at DTG peak temperatures were also calculated. [ABSTRACT FROM AUTHOR]

Circulating microRNAs (miRNAs) were found to exist in serum/plasma in a highly stable, cell-free form, and aberrantly expressed in many human diseases. Currently, the expression levels of circulating miRNAs are estimated by quantitative real-time polymerase chain reaction. However, no study has systematically evaluated reference genes for evaluating circulating microRNA expression. This study describes the identification and characterization of an appropriate reference gene for the normalization of circulating miRNA levels in hepatitis B virus (HBV)-infected patients and healthy people. Ten miRNAs that resemble the mean expression of the TaqMan low density array together with U6, RNU6B, and miR-16 were validated with two algorithms, geNorm, and NormFinder, after ensuring their equivalent expression between the two study groups. The combination of miR-26a, miR-221, and miR-22* is recommended as the most stable set of reference genes for circulating miRNA evaluation in HBV patients and healthy people. [ABSTRACT FROM AUTHOR]

The mechanical characteristics of the weld joint were investigated by tensile test, microstructure test, and microhardness test. The welded tube NC bending tests were carried out to evaluate the weld on the formability of the QSTE340 welded tube. The results show that the wall thinning degree, cross-sectional deformation and springback angle increase significantly as the weld line is located on the outside of the bend compared with that located on the middle and inside, and the welded tubes produce nearly identical performance as the weld line is located on the middle and inside. The wall thickening degree decreases much as the weld line is located on the inside of the bend. So the welded tube can acquire good bending formability as the weld line is located in the region away from the outside of the bend. [ABSTRACT FROM AUTHOR]

A new binuclear complex [Sm( p-MOBA)3bipy]2 · 2C2H5OH ( p-MOBA = p-methoxybenzoate, bipy = 2,2′-bipyridine) has been prepared via dissolution reaction in an ethanol/water mixed solution and characterized by elemental analysis, IR, UV, XRD and molar conductance, respectively. Its single crystal was characterized by X-ray single crystal diffraction. The crystal belongs to triclinic system, space group P $$ \bar 1 $$. The crystallographic data are: a = 10.970(3) Å, b = 11.507(4) Å, c = 13.931(4) Å, α = 84.449(4)°, β = 76.403(4)°, γ = 87.284(4)°, Z = 1, D r = 1.574 Mg/m3, FW = 1612.02, F(000) = 814, R1 = 0.0275, wR 2 = 0.0646. Two Sm3+ ions are linked by four carboxylic groups with bidentate bridging and tridentate chelating-bridging coordination modes. Each center Sm3+ is nine coordinated with a distorted tri-capped triangular prism geometry. [ABSTRACT FROM AUTHOR]