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Purpose: This work proposed a convolutional neural network (CNN)-based method trained with images acquired with electron density phantoms to reduce quantum noise for coronary artery calcium (CAC) scans reconstructed with slice thickness less than 3 mm., Methods: A DenseNet model was used to estimate quantum noise for CAC scans reconstructed with slice thickness of 0.5, 1.0 and 1.5 mm. Training data was acquired using electron density phantoms in three different sizes. The label images of the CNN model were real noise maps, while the input images of the CNN model were pseudo noise maps. Image denoising was conducted by subtracting the CNN output images from thin-sliced CAC scans. The efficacy of the proposed method was verified through both phantom study and patient study., Results: By means of phantom study, the proposed method was proven effective in reducing quantum noise in CAC scans reconstructed with 1.5-mm slice thickness without causing significant texture change or variation in HU values. With regard to patient study, calcifications were more clear on the denoised CAC scans reconstructed with slice thickness of 0.5, 1.0 and 1.5 mm than on 3-mm slice images, while over-smooth changes were not observed in the denoised CAC scans reconstructed with 1.5-mm slice thickness., Conclusion: Our results demonstrated that the electron density phantoms can be used to generate training data for the proposed CNN-based denoising method to reduce quantum noise for CAC scans reconstructed with 1.5-mm slice thickness. Because anthropomorphic phantom is not a necessity, our method could make image denoising more practical in routine clinical practice., (© 2024 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

Objectives: Interscan reproducibility of coronary artery calcium (CAC) scoring can be improved by using a smaller slice thickness but at the cost of higher image noise. This study aimed to investigate the feasibility of using densely connected convolutional network (DenseNet) to reduce the image noise in CAC scans reconstructed with slice thickness < 3 mm for improving coronary calcification detection in CT., Methods: Phantom data acquired with QRM and CIRS phantoms were used for model training and testing, where the DenseNet model adopted in this work was a convolutional neural network (CNN) designed for super resolution recovery. After phantom study, the proposed method was evaluated in terms of its ability to improve calcification detection using patient data. The CNN input images (IMG input ) were CAC scans reconstructed with 0.5-, 1.0- and 1.5-mm slice thickness, while CNN label images were CAC scans reconstructed with 3-mm slice thickness (IMG 3mm ). Region of interest (ROI) analysis was carried out on IMG 3mm , IMG input and CNN output images (IMG output ). Two-sample t test was used to compare the difference in Hounsfield Unit (HU) values within ROI between IMG 3mm and IMG output ., Results: For the calcifications in QRM phantoms, no statistically significant difference was found when comparing the HU values of 400- and 800-HA calcifications identified on IMG 3mm to those on IMG output with slice thickness of 0.5, 1.0 or 1.5 mm. On the other hand, statistically significant difference was found when comparing the HU values of 200-HA calcifications identified on IMG 3mm to those on IMG output with a slice thickness of 0.5 and 1.0 mm. Meanwhile, no statistically significant difference was found when comparing the HU values of 200-HA calcifications identified on IMG 3mm to those on IMG output with a slice thickness of 1.5 mm. As for the rod inserts in CIRS phantoms simulating 9 different tissue types in human body, there was no statistically significant difference between IMG 3mm and IMG output with slice thickness of 1.5 mm, and all the p values were larger than 0.10. With regards to patient study, more calcification pixels were detected on IMG output with a slice thickness of 1.5 mm than on IMG 3mm , so calcifications were more clear on the denoised images., Conclusion: According to our results, the CNN-based denoising method could reduce statistical noise in IMG input with a slice thickness of 1.5 mm without causing significant texture change or variation in HU values. The proposed method could improve cardiovascular risk prediction by detecting small and soft calcifications that are barely identified on 3-mm slice images used in conventional CAC scans., (Copyright © 2022 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

A characteristic feature of human cognition is our ability to 'multi-task'-performing two or more tasks in parallel-particularly when one task is well learned. How the brain supports this capacity remains poorly understood. Most past studies have focussed on identifying the areas of the brain-typically the dorsolateral prefrontal cortex-that are required to navigate information-processing bottlenecks. In contrast, we take a systems neuroscience approach to test the hypothesis that the capacity to conduct effective parallel processing relies on a distributed architecture that interconnects the cerebral cortex with the cerebellum. The latter structure contains over half of the neurons in the adult human brain and is well suited to support the fast, effective, dynamic sequences required to perform tasks relatively automatically. By delegating stereotyped within-task computations to the cerebellum, the cerebral cortex can be freed up to focus on the more challenging aspects of performing the tasks in parallel. To test this hypothesis, we analysed task-based fMRI data from 50 participants who performed a task in which they either balanced an avatar on a screen (balance), performed serial-7 subtractions (calculation) or performed both in parallel (dual task). Using a set of approaches that include dimensionality reduction, structure-function coupling, and time-varying functional connectivity, we provide robust evidence in support of our hypothesis. We conclude that distributed interactions between the cerebral cortex and cerebellum are crucially involved in parallel processing in the human brain., (© 2023 Massachusetts Institute of Technology.)

Patient outcomes of non-small-cell lung cancer (NSCLC) vary because of tumor heterogeneity and treatment strategies. This study aimed to construct a deep learning model combining both radiomic and clinical features to predict the overall survival of patients with NSCLC. To improve the reliability of the proposed model, radiomic analysis complying with the Image Biomarker Standardization Initiative and the compensation approach to integrate multicenter datasets were performed on contrast-enhanced computed tomography (CECT) images. Pretreatment CECT images and the clinical data of 492 patients with NSCLC from two hospitals were collected. The deep neural network architecture, DeepSurv, with the input of radiomic and clinical features was employed. The performance of survival prediction model was assessed using the C-index and area under the curve (AUC) 8, 12, and 24 months after diagnosis. The performance of survival prediction that combined eight radiomic features and five clinical features outperformed that solely based on radiomic or clinical features. The C-index values of the combined model achieved 0.74, 0.75, and 0.75, respectively, and AUC values of 0.76, 0.74, and 0.73, respectively, 8, 12, and 24 months after diagnosis. In conclusion, combining the traits of pretreatment CECT images, lesion characteristics, and treatment strategies could effectively predict the survival of patients with NSCLC using a deep learning model.

This study aimed to facilitate pseudo-CT synthesis from MRI by normalizing MRI intensity of the same tissue type to a similar intensity level. MRI intensity normalization was conducted through dividing MRI by a shading map, which is a smoothed ratio image between MRI and a three-intensity mask. Regarding pseudo-CT synthesis from MRI, a conversion model based on a three-layer convolutional neural network was trained and validated. Before MRI intensity normalization, the mean value ± standard deviation of fat tissue in 0.35 T chest MRI was 297 ± 73 (coefficient of variation (CV) = 24.58%), which was 533 ± 91 (CV = 17.07%) in 1.5 T abdominal MRI. The corresponding results were 149 ± 32 (CV = 21.48%) and 148 ± 28 (CV = 18.92%) after intensity normalization. With regards to pseudo-CT synthesis from MRI, the differences in mean values between pseudo-CT and real CT were 3, 15, and 12 HU for soft tissue, fat, and lung/air in 0.35 T chest imaging, respectively, while the corresponding results were 3, 14, and 15 HU in 1.5 T abdominal imaging. Overall, the proposed workflow is reliable in pseudo-CT synthesis from MRI and is more practicable in clinical routine practice compared with deep learning methods, which demand a high level of resources for building a conversion model.

This study was designed to identify whether the position and size of the region of interest (ROI) influence extracellular volume fraction (ECV) measurements. Patients with localized (n = 203) or infiltrative (n = 215) cardiomyopathies and 36 normal controls were enrolled in this study. ECV measurements at 4 different regions, including the anterior, septal, posterior and lateral wall regions, were measured, and all groups were compared. Regional ECV was correlated with the corresponding regional wall thickness. The diagnostic power to differentiate the myocardial abnormalities was evaluated for each myocardial region. ECVs measured using five different ROI sizes within each myocardial region were compared. Our results showed that ECVs varied among the myocardial regions, and this variation was significantly associated with regional wall thicknesses. For the detection of myocardial abnormalities, regional ECV revealed similar results as ECV derived from the whole region except for the anterior region. No significant difference was found in the ECVs measured using the five different ROI sizes. In conclusion, CMR-derived ECVs vary with myocardial region, and this variation is significantly associated with the regional wall thickness. In contrast, the measured size of the ROI has less of an effect on the ECV.

Aqueous palladium-catalyzed direct arylation polymerization (DArP) of 2-bromothiophene derivatives 6-(2-(2-bromothiophen-3-yl)ethoxy)hexyl trimethylammonium bromide (T1) and 4-(2-(2-bromothien-3-yl)ethoxy)butylsulfonate (T2) is achieved. The supporting ligand, triphenylphosphine-3,3',3''-trisulfonic acid trisodium salt (m-TPPTs), facilitates DArP of both derivatives; however, its separation from the polymers by dialysis is difficult due to its strong aggregation in water and N,N-dimethylacetamide (DMAc). This is supported by dynamic light scattering, gel permeation chromatography (GPC), and single-crystal X-ray crystallography. Pyrimidine-Pd(OAc) 2 is utilized in the DArP of T1 to afford PT1 without ligand contamination. Density functional theory calculations to determine the coordinating capability of the carboxylate/pivalic acid/water to palladium indicate the viability of implementing DArP in water. Finally, polyelectrolyte molecular-weight overestimation by GPC in water is attributed to the polyelectrolyte effect. Aggregation of the conjugated polyelectrolytes leads to a contracted hydrodynamic volume, and the molecular weight and dispersity assessed by GPC in DMAc significantly deviate from the actual values. An objective approach to evaluate the molecular weight for conjugated polyelectrolytes requires further development., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose: This work investigated the simultaneous influence of tube voltage, tube current, body size, and HU threshold on calcium scoring reconstructed at 0.5-mm slice thickness using iterative reconstruction (IR) through multivariate analysis. Regression results were used to optimize the HU threshold to calibrate the resulting Agatston scores to be consistent with those obtained from the conventional protocol., Methods: A thorax phantom set simulating three different body sizes was used in this study. A total of 14 coronary artery calcium (CAC) protocols were studied, including 1 conventional protocol reconstructed at 3-mm slice thickness, 1 FBP protocol, and 12 statistical IR protocols (3 kVp values*4 SD values) reconstructed at 0.5-mm slice thickness. Three HU thresholds were applied for calcium identification, including 130, 150, and 170 HU. A multiple linear regression method was used to analyze the impact of kVp, SD, body size, and HU threshold on the Agatston scores of three calcification densities for IR-reconstructed CAC scans acquired with 0.5-mm slice thickness., Results: Each regression relationship has R 2 larger than 0.80, indicating a good fit to the data. Based on the regression models, the HU thresholds as a function of SD estimated to ensure the quantification accuracy of calcium scores for 120-, 100-, and 80-kVp CAC scans reconstructed at 0.5-mm slice thickness using IR for three different body sizes were proposed. Our results indicate that the HU threshold should be adjusted according to the imaging condition, whereas a 130-HU threshold is appropriate for 120-kVp CAC scans acquired with SD = 55 for body size of 24.5 cm., Conclusion: The optimized HU thresholds were proposed for CAC scans reconstructed at 0.5-mm slice thickness using IR. Our study results may provide a potential strategy to improve the reliability of calcium scoring by reducing partial volume effect while keeping radiation dose as low as reasonably achievable., (© 2019 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

Topological insulators (TIs) have emerged as some of the most efficient spin-to-charge convertors because of their correlated spin-momentum locking at helical Dirac surface states. While endeavors have been made to pursue large "charge-to-spin" conversions in novel TI materials using spin-torque-transfer geometries, the reciprocal process "spin-to-charge" conversion, characterized by the inverse Edelstein effect length (λ IEE ) in the prototypical TI material (Bi 2 Se 3 ), remains moderate. Here, we demonstrate that, by incorporating a "second" spin-splitting band, namely, a Rashba interface formed by inserting a bismuth interlayer between the ferromagnet and the Bi 2 Se 3 (i.e., ferromagnet/Bi/Bi 2 Se 3 heterostructure), λ IEE shows a pronounced increase (up to 280 pm) compared with that in pure TIs. We found that λ IEE alters as a function of bismuth interlayer thickness, suggesting a new degree of freedom to manipulate λ IEE by engineering the interplay of Rashba and Dirac surface states. Our finding launches a new route for designing TI- and Rashba-type quantum materials for next-generation spintronic applications.

With the method of combining field sampling and plot test, we took saline-alkali paddy field of Qianguo county, Jilin province as an investigation object. According to the nature of soil in the area, we monitored CH4 and N2O which released from soil during rice growth period and tested the soil pH and soil organic carbon to analyze the law and reasons of greenhouse gas emission in the paddy fields. The results showed that N2O emission from paddy fields presented three peaks with distinct seasonal patterns. Application of fertilizer provided additional reactive substrate, which affected N2O emission significantly. Under flooding conditions, the main source of N2O is a denitrification process, while after drainage, nitrification was the predominance. CH4 emission showed a single peak at rice tillering stage when rice grew vigorously. That deoxidation condition dominated in the deep water layer in the paddy fields provided suitable conditions for CH4 producing microorganisms, which result in the emergence of CH4 emission peak. The pH doesn't have an obvious influence on CH4 and N2O, while SOC content in soil and pattern of CH4 emission showed a significantly positive correlation.

A home-made chemical ionization time-of-flight mass spectrometer (TOFMS) has been developed for continuous measurements of atmospheric hydroxyl radical. Based on the atmospheric pressure chemical ionization technique, an ionization source with orthogonal dual tube structure was adopted in the instrument, which minimized the interference between the reagent gas ionization and the titration reaction. A 63Ni radioactive source was fixed inside one of the orthogonal tubes to generate reactant ion of NO(-)(3) from HNO3 vapor. Hydroxyl radical was first titrated by excess SO2 to form equivalent concentrations of H2SO4 in the other orthogonal tube, and then reacted with NO(-)(3) ions in the chemical ionization chamber, leading to HSO(-)(4) formation. The concentration of atmospheric hydroxyl radical can be directly calculated by measuring the intensities of the HSOj product ions and the NO(-)(3) reactant ions. The analytical capability of the instrument was demonstrated by measuring hydroxyl radical in laboratory air, and the concentration of the hydroxyl radical in the investigated air was calculated to be 1.6 x 106 molecules*cm ', based on 5 seconds integration. The results have shown that the instrument is competent for in situ continuous measurements of atmospheric trace radical.

Two new kelsoane-type sesquiterpenes, namely kelsoenethiol (1) and dikelsoenyl ether (2), were obtained from the Formosan soft coral Nephthea erecta. Their structures were elucidated through extensive spectroscopic analyses, ESI orbitrap mass and quantum chemical calculations (QCC). The cytotoxicity against A-459 (human lung carcinoma), P-388 (mouse lymphocytic leukemia), and HT-29 (human colon adenocarcinoma) cancer cell lines of 1 and 2 was evaluated in vitro. Compound 1 showed cytotoxicity against P-388 and HT-29 cells with ED50s of 1.3 and 1.8 μg/mL, respectively., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

With the features of a broad range of ionizable compounds, reduced fragments and simple mass spectrum, a homemade magnetic field enhanced photoelectron ionization (MEPEI) source combined with single photon ionization (SPI) for time-of-flight mass spectrometer was built and applied to analyze thermal decomposition/combustion products of polyvinyl chloride (PVC). The combined ion source can be switched very fast between SPI mode and SPI-MEPEI mode for detecting different targeted compounds, and only adjusting the voltage of the electrode in the ionization region to trigger the switch. Among the PVC thermal decomposition/combustion products, HCl and CO2, which ionization energies (12.74 eV, 13.77 eV respectively) were higher than the energy of photon (10.60 eV), were ionized by MEPEI, while alkenes, dichloroethylene, benzene and its homologs, monochlorobenzene, styrene, indane, naphthalene and its homologs were ionized by SPI and MEPEI simultaneously. Spectra of interested products as a function of temperatures indicated that products are formed via two main mechanisms: (1) dechlorination and intramolecular cyclization can lead to the formation of HCl, benzene and naphthalene at 250-370 degrees C; (2) intermolecular crosslinking leads to the formation of alkyl aromatics such as toluene and xylene/ethylbenzene at 380-510 degrees C. The experimental results show that the combined ion source of SPI/ SPI-MEPEI for TOF-MS has broad application prospects in the online analysis field.

An ion mobility spectrometer array was designed, in order to broaden the detection range of ion mobility spectrometer and improve the accuracy of compound identification. This instrument was based on the combination of ionization sources of 63Ni positive ion mode, 63Ni negative ion mode and photoionization mode with vacuum UV lamp, and it can continuously monitor the volatile organic compounds in air. With the automatic system of sampling and injection of this instrument, the positive ion of dimethyl sulfoxide and negative ion of dichloromethane were detected simultaneously. By comprehensive analysis of spectra with ion mobility spectrometer array, acrylonitrile, m-xylene and acetone were identified, which were difficult to be distinguished under the 63Ni positive ion mode. Acetone samples were determined quantitatively within four days continuously, and the results indicated that the linear range of acetone in this instrument was 2 orders of magnitude. The linear correlation coefficient R was higher than 0.995, and the relative standard deviations were controlled in the range of 4.0%-18.3%. Methacrylate leaked in simulation was monitored on-line for 24 h continuously, using the method of dynamic tracking, and the result showed the leaking time and the concentration of methacrylate directly.

A home-made membrane inlet- single photon ionization/chemical ionization- time-of-flight mass spectrometer has been described. A vacuum ultraviolet (VUV) lamp with photon energy of 10.6 eV was used as the light source for single photon ionization (SPI). Chemical ionization (CI) was achieved through ion-molecule reactions with O2- reactant ions generated by photoelectron ionization. The two ionization modes could be rapidly switched by adjusting electric field in the ionization region within 2 s. Membrane inlet system used for rapid enrichment of volatile organic compounds (VOCs) in water was constructed by using a polydimethylsiloxane (PDMS) membrane with a thickness of 50 microm. A purge gas was added to accelerate desorption of analytes from the membrane surface. The purge gas could also help to prevent the pump oil back-streaming into the ionization region from the analyzer chamber and improve the signal to noise ratio (S/N). Achieved detection limits were 2 microg x L(-1) for methyl tert-butyl ether (MTBE) in SPI mode and 1 microg x L(-1) for chloroform in SPI-CI mode within 10 s analysis time, respectively. The instrument has been successfully applied to the rapid analysis of MTBE in simulated underground water nearby petrol station and VOCs in disinfected drinking water. The results indicate that the instrument has a great application prospect for online analysis of VOCs in water.

Airlift bioreactor containing polyvinyl-alcohol-immobilized cell beads was investigated for its capability of biodegradation of dimethyl sulfoxide (DMSO) in term of sludge characteristics including the strategy of acclimation with sucrose and the protection of microorganism from poisoning of DMSO by PVA cell beads. Media condition with sucrose at 50 mg L(-1) was beneficial to the biodegradation of DMSO in the fresh PVA entrapped-sludge, but became insignificant in the acclimated one as for tolerance of DMSO toxicity. The removal efficiency of DMSO had the highest rate at 1.42-kg DMSO per kilogram of suspended solid per day after series acclimation batches in the oxygen-enriched airlift bioreactor treated with the 1187.4 mg L(-1) of DMSO. Microbial consortium was required for the complete biodegradation of DMSO without any dimethyl sulfide produced. Pseudomonas sp. W1, excreting extracellular monooxygenase identified by indole, was isolated to be one of the most effective DMSO-degrading microorganism in our airlift bioreactor., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

In this report, the effects of conductive polymer oxidation states and structures on the design and development of ionic liquid (IL)/conductive polymer (CP) composite films for gas sensing are systematically characterized. Four different polyvinyl ferrocene (PVF) films synthesized by varying the conditioning potential (0.7 vs 0.0 V) and the electrolyte are tested for their gas-sensing properties (e.g., sensitivity, selectivity, response time, linearity, and dynamic range against various gas analytes such as dichloromethane, ethanol, natural gas, methane, formaldehyde (37%), and benzene) utilizing the quartz crystal microbalance (QCM) and ATR-FT-IR. The best available film is further studied as a substrate for the immobilization of various ILs that enhanced both the sensitivity and selectivity. Finally, two arrays, each comprising four sensors with the following scheme are developed and characterized for their ability to classify the four target analytes by using linear discriminant analysis: (1) the highest sensitivity PVF film immobilized with four different ILs and (2) the highest sensitivity IL immobilized in four different PVF films. Array 2 is proven to be much better than array 1 in discriminating the analytes, which is very significant in establishing the fact that a diverse set of PVF redox states allow the rational development of a PVF/IL composite-based sensor array in order to analyze complex mixtures utilizing structural differences and the extent of intermolecular interactions., (© 2011 American Chemical Society)

Background: Human epidermal growth factor 2 (HER2) is one of the most important prediction factors, but only 25% - 30% of breast cancer patients HER2 are positive. It is unknown whether there are other molecular markers that could be used to predict prognosis and recurrence in HER2 negative patients. This study investigated correlations of cyclin A2 and HER2 levels with clinical outcomes in 281 patients with invasive breast cancer in order to identify whether cyclin A2 can serve as a prognostic factor in HER2 negative patients., Methods: Immunohistochemical staining was used to detect cyclin A2 and HER2 expression in 281 patients. Cyclin A2 and HER2 gene amplifications were analyzed using gene analysis and RT-PCR in 12 patients. Risk and survival estimates were analyzed using Log-rank, Kaplan-Meier, and Cox regression analysis; cyclin A2 and HER2 consistency with survival were analyzed using Kappa analysis., Results: Patients with higher cyclin A2 and HER2 expressions had significantly shorter disease-free survival periods (P = 0.047 and P = 0.05, respectively). Kappa analysis performed that cyclin A2 and HER2 showed a low Kappa index (kappa = 0.37), allowing us to conclude that cyclin A2 and HER2 detect different pathologies. Gene analysis and RT-PCR showed that cyclin A2 was upregulated in patients with early relapse; the average increase was 3.69 - 2.74 fold., Conclusions: Cyclin A2 and HER2 are associated with proliferation and high recurrence, particularly when combined. Cyclin A2 is easily detected by nuclear staining and might be a useful biomarker for recurrence risk in HER2 negative patients.

Objective: To assess the antitumor activity and safety of aromatase inhibitors in advanced breast cancer., Methods: Fifty-two advanced and female breast cancer patients with measurable and /or bone valuable tumor lesions were observed from June 2003 to September 2006. They were treated by aromatase inhibitors for at least 24 weeks, of whom 11 were treated less than 24 weeks because of disease progress; their age range was from 37 to 75 years (median 58); 8 patients were pre-menopausal, 6 with ovarian ablation and 2 with Goserelin to suppress ovarian function. Thirty-six patients were treated with exemestane, 13 with anastrozole and 3 with letrozole. Major items were observed including objective response rate (ORR=CR+PR), clinical benefit rate (CBR=CR+PR+SD>or=24 weeks), time to progress (TTP), time to failure (TTF), safety and toxicity., Results: CR were 6 cases (11.5%) , with 1 case going on for 152 weeks, 1 case for 96 weeks, and other 4 cases for longer than 60 weeks; PR were 19 cases (36.5%), lasting 32-96 weeks; 16 cases obtained SD>or=24 weeks(30.8%); and 11 cases PD (progress of disease)+SD<24 weeks (21.2%). ORR were 48%, CBR 78.8%, and TTP 78.87 weeks (95% CI 61.13%-96.61%); although the patients who did not achieve objective response (group B) were treated with chemotherapy, radiotherapy or another kind of aromatase inhibitor, but their survival time was significantly different from that of the patients who achieved objective response (group A) when defined by Kaplan-Meier survival estimate. The over survival was 92% in group A, and 81.5% in group B when patients follow up more than 24 weeks [Log Rank (Mantel-Cox) analysis, chi2=3.85, P=0.047]; side effects were observed such as arthralgia, sweating, hot flash, and 2 patients developed heart failure with uncertain related drug before recovery., Conclusion: The single agent effective rate of aromatase inhibitor was 48%. The patients had long term survival if they obtained CR or PR, and the side effects were well tolerated.

The iron oxide/bentonite was prepared through a reaction of a solution of OH-Fe salt with bentonite clay dispersion. BET, XRD an d HRTEM were used t o study i ts surface area, microstructure, and average particle size. The iron oxide/bentonite nano composite was developed as the heterogeneous catalyst for successful discoloration and mineralization of dye rhodamine B And the effects of solution pH, H2O2 molar concentration, catalyst loading and initial rhodamine B concentration were studied in detail by photometric method. The process of degradation was traced by UV-Visible spectrum. Besides, the comparison between the heterogeneous photo-Fenton process and homogeneous photo-Fenton process was performed. The result shows that, it has large surface area and mainly consists of high catalytic activity alpha-Fe2O3. The discoloration ratio is up to 97% and the COD(Cr), removal ratio is 71% after 4 h in the presence of pH 3.0, 2.5 x 10(-5) mol x L(-1) rhodamine B 100 mL, 0.3 g x L(-1) catalyst, 10 mmol x L(-1) H2O2 and UV. The rhodamine B degradating speed of heterogeneous photo-Fenton process is much faster than that of homogeneous photo-Fenton process. The catalyst can be reused after being treated.

Objective: To identify the FTIR spectroscopic characterization of breast cancer and explore the possibility of application of FTIR in differentiation of malignant and benign breast lesions., Methods: FTIR spectra of surgically removed fresh breast tissues were measured by spectrometer equipped with mid-infrared fiber optics and an ATR probe. Peaks in the spectra were measured and relative intensity ratios were calculated and analyzed if there are significant differences between the spectra of malignant and benign breast lesions., Results: There were significant differences (P < 0.05) between the spectra of malignant breast cancers and benign breast tissues in the relative intensity ratios of different peaks (I1640/ I1550 and I1160/I1120 for protein structures; I1640/I1460 and I1550/I1460 for relative content of protein and lipid; I1460/I1400 for lipid structures; I1310/I1240 for nucleic acid)., Conclusion: FTIR spectroscopy could be a useful tool in clinical diagnosis of breast cancer.

Objective: To study the expression of cerbB-2 and its clinical biology value in Chinese breast cancer patients by evidence based medical analysis., Methods: All the published studies about cerbB-2 and breast cancer for the last 10 years were reviewed and standard techniques of meta-analysis to combined with the results of these studies were used to produce a more precise estimate of the prognostic significance expression of cerbB-2., Results: The mean of cerbB-2 positive expression was 50% (95% confidence interval 48%-54%), cerbB-2 positive expression was related with node metastasis, recurrence after surgery and survival time; the RR values were 1.71, 2.14 and 2.32 respectively; tumor size, nuclear grade and pathology type were also the important factors that were related with the expression of cerbB-2, while the expression was not related with age; cerbB-2 was a special and sensitive prognostic factor for breast cancer., Conclusion: cerbB-2 can be used as an independent molecular marker for definitive prognosis of breast cancer, as well as a reliable marker for choice of standard and individual therapy.

A Huisgen 1,3-dipolar cycloaddition "click chemistry" was employed to immobilize azido sugars (mannose, lactose, alpha-Gal) to fabricate carbohydrate self-assembled monolayers (SAMs) on gold. This fabrication was based on preformed SAM templates incorporated with alkyne terminal groups, which could further anchor the azido sugars to form well-packed, stable, and rigid sugar SAMs. The clicked mannose, lactose, and alpha-Gal trisaccharide SAMs were used in the analysis of specific carbohydrate-protein interactions (i.e., mannose-Con A; ECL-lactose, alpha-Gal-anti-Gal). The apparent affinity constant of Con A binding to mannose was (8.7 +/- 2.8) x 10(5) and (3.9 +/- 0.2) x 10(6) M(-1) measured by QCM and SPR, respectively. The apparent affinity constants of lactose binding with ECL and alpha-Gal binding with polyclonal anti-Gal antibody were determined to be (4.6 +/- 2.4) x 10(6) and (6.7 +/- 3.3) x 10(6) M(-1), respectively by QCM. SPR, QCM, AFM, and electrochemistry studies confirmed that the carbohydrate SAM sensors maintained the specificity to their corresponding lectins and nonspecific adsorption on the clicked carbohydrate surface was negligible. This study showed that the clicked carbohydrate SAMs in concert with nonlabel QCM or SPR offered a potent platform for high-throughput characterization of carbohydrate-protein interactions. Such a combination should complement other methods such as ITC and ELISA in a favorable manner and provide insightful knowledge for the corresponding complex glycobiological processes.

A simple method was used to prepare a "switchable" electrode surface by using self-assembled monolayers of dodecanethiol on a gold electrode. The dodecane-modified electrode was electrochemically inactive until the monolayer was soaked in solutions of 1,10-phenanthroline or 2,2'-bipyridine. The electroactive form of the electrode could be reverted back to the nonelectroactive form by rinsing the electrode. Surface IR results showed that both dodecanethiol and 1,10-phenanthroline exist in the mixed monolayer.

The authors detected ten normal breast tissue samples and eight breast cancer samples by FTIR spectroscopy with an ATR probe. Nineteen variables of thirteen bands in the spectra were compared using standard statistic methods. The results demonstrated that bands of protein, lipid, carbohydrate, and nucleic acid from cancerous samples were significantly different from those from normal ones: (1) The relative intensity of N-H band increased and amide I band shifted to lower wave number significantly; (2) Symmetric and antisymmetric vibrations of -CH2 group, C=O vibration, and relative intensity of (-CH2)n decreased; (3) The intensity of 1160 cm(-1) band was much weaker than that of 1120 cm(-1); (4) The band of P=O or P-O-C shifted toward lower wave number. The authors believe that FTIR spectroscopy has a promising future in breast cancer diagnosis.

Objective: To study the efficacy of liver transplantation on end-stage hepatitis B related liver diseases, and the prevention and treatment strategies of hepatitis B recurrence after the transplantation., Methods: The efficacy of combined treatment of lamivudine and hepatitis B immune globulin (HBIG) therapy on 24 patients who had received liver transplantation was retrospectively studied., Results: All the 24 patients with end-stage hepatitis B-related liver diseases treated with lamivudine alone or combined therapy of lamivudine and HBIG showed normal liver function and 21 of them lost hepatitis B virus (HBV) markers. However, the remaining 3 patients became HBsAg positive again soon after liver transplantation., Conclusions: Liver transplantation is effective for patients with end-stage hepatitis B-related liver diseases. Combined treatment of lamivudine and HBIG may prevent the recurrence of hepatitis B after the operation.

The experiment aimed at studying long-term cryopreservation of hepatocytes and therapeutic effect of their transplantation for acute hepatic failure. Hepatocytes of wistar rats were cryopreserved in liquid nitrogen for 30, 60, 90, and 180 days. Their viabilities were respectively 71.2%, 75.7%, 69.7%, and 73.5% of fresh cells', however, there were no significant differences among all cryopreserved groups. Differences of viably intra-hepatocellular enzyme contents among all groups, such as glutamic oxaloacetic transaminase and so on, were not significant. Morphologically intact hepatocytes were observed under light microscopy and transmission electron microscopy. Survival rate of Sprague-Dawley rats with acute hepatic failure were increased from 1/8 to 5/7 because of the transplantation of syngeneic frozen hepatocytes (P = 0.035). The results showed that after 30 days of cryopreservation in liquid nitrogen, the viability of hepatocytes decreased significantly, but no longer decreased in subsequent freeze up to 180 days. The viable intact cells and their normal enzyme contents were kept. The acute hepatic failure could be treated by them.

Severe acute pancreatitis is highly controversial on its diagnostic criteria, the optimum time for surgery, the selection of surgical procedures, and the prevention and treatment of complications. We treated 40 patients with severe acute pancreatitis from July 1983 to July 1988. The comparison of clinical and laboratory data of severe acute pancreatitis and mild acute pancreatitis showed that in some patients neither Ranson's nor Bank's criteria are reliable in classifying or predicting the severity of the disease. The coexistence of acute peritonitis and bloody ascites with elevated amylase level is very helpful to identify the local conditions of pancreatic necrosis and hemorrhage. We suggest early operation (within 48 hours) be applied in severe acute pancreatitis. In our series, five types of surgical procedures were used. We consider that proper treatment of acute respiratory distress syndrome (ARDS) is most important in the management of severe pancreatitis.

In general, frontal sections of the liver in magnetic resonance imaging are used less than sections passing through other planes of space. Frontal sections of the trunk in magnetic resonance imaging involving the liver, performed in over 80 patients for various reasons, were compared with frontal sections of the trunk made in 10 cadavers. A general schema was established of the anatomy of the liver studied in the frontal plane. Frontal sections in magnetic resonance imaging make it possible to form a very good estimate of the structure and size of the liver, and to recognize individual variations. They clearly show certain inferior relations of the liver. In particular, frontal sections in magnetic resonance imaging make it possible to identify most of the main veins of the liver, the main lobar veins and branches of the portal vein, and to properly study the entire retrohepatic portion of the inferior vena cava. Some of the vascular images were found almost constantly in the sections of the various subjects. The right lobe of the liver is more accessible to such study than the left by reason of its structure and its venous arrangements. Frontal sections of the liver in magnetic resonance imaging constitute a preferential method for studying the anatomy of the liver. Together with transverse sections, they make it possible to specify the site and venous relations of a pathologic process within the liver, with a view to hepatectomy.