[Distribution of Biodegradable Dissolved Organic Matter and Its Affecting Factors in a Typical Peri-urban Watershed in Yangtze River Delta]

Dissolved organic matter (DOM) plays key roles in the carbon biogeochemical cycle, and biodegradable dissolved organic matter (BDOM) is one of the key fractions of DOM. Rapid urbanization and intensive human activities substantially influence the distribution of DOM at the watershed scale. Identifying the spatial and temporal variability in BDOM has become an important and urgent issue of water quality control in rapid urbanization areas. However, limited studies have been conducted to explore the role of human activities on the occurrence and distribution of BDOM in peri-urban watersheds. In this study, the spatial and temporal distribution of BDOM and related affecting factors were investigated in a typical peri-urban watershed (Zhangxi watershed) located at Ningbo City in Yangtze River Delta. Water samples were collected in wet and dry seasons in 2019 based on topographic features, land use, and intensity of human activities. The BDOM were characterized by fluorescence excitation-emission matrix and parallel factor analysis (EEM-PARAFAC), and land use patterns were analyzed using the Source-Sink Landscape Model. The results of this study showed that the BDOM concentrations ranged from 0.57 to 6.80 mg·L^-1. Obvious spatial and temporal heterogeneities of BDOM were found at the watershed scale, and significantly higher concentrations of BDOM were observed in the wet season than those in the dry season. Furthermore, relatively high concentrations of BDOM were found in areas with relatively higher intensive human activities. Two fluorescent components (a terrestrial humic-like substance and protein-like substance) were observed using the PARAFAC model. The results of spatial analysis showed that terrestrial humic-like fluorescent components were closely positively correlated with anthropogenic parameters (percentages of agricultural and urban land and ratio of source and sink landscapes). The results showed that the occurrence and distribution of BDOM were strongly influenced by human activities, which could provide scientific guidance for water quality control and related land management in peri-urban aquatic ecosystems.

[Relationship Between Source-Sink Landscape Pattern and Antibiotics in Surface Water in Peri-urban Watershed]

Quantitively identifying the effect of land use patterns on antibiotics in surface water has significance in maintaining water quality and protecting residents' health in urban and rural regions. In this study, a typical peri-urban watershed, located in the Yangtze River Delta, was selected as the study area. Based on surface water sampling, laboratory analysis, and source-sink landscape model (SSLM) analysis, the component and distribution characteristics of antibiotics in surface water in different sub-watersheds were analyzed. The effects of source and sink landscape patterns on antibiotic concentrations in surface water were identified. The results of this study showed substantial differences in types and concentrations of antibiotics in surface water in different sub-watersheds. The total concentrations of antibiotics in surface water ranged from 1.12 ng·L^-1 to 53.74 ng·L^-1. From upstream to downstream, the area of "source" landscape increased, and the area of "sink" landscape decreased based on landscape pattern analysis. The results of non-metric multidimensional scaling (NMDS) showed that sub-watersheds with similar "source-sink" landscape patterns were detected as having similar antibiotics types and concentrations in surface water. Land use composition, distance, elevation, and slope degree had substantial impacts on antibiotic concentrations in surface water. The results of this study also found that location-weighted landscape index (LWLI) was positive correlated with antibiotics concentrations in surface water based on correlation analysis and redundancy analysis. The sub-watersheds with high LWLI values usually had relatively higher antibiotic concentrations in surface water. This study indicated that optimization of "source" and "sink" landscapes at the watershed scale can decrease antibiotic contamination in surface water. Furthermore, SSLM is an effective tool in landscape optimization at the watershed scale.

[Fluorescence Characteristics and Influencing Factors of Dissolved Organic Matter (DOM) in Water and Sediment of Urban Watershed: A Case Study of Xiaojia River in Ningbo City]

Rapid urbanization has a significant impact on dissolved organic matter (DOM) in water and sediment; thus, it is important to explore the distribution characteristics and influencing factors of DOM in watersheds. Xiaojia River is a typical urban area in Beilun District of Ningbo City, Yangtze River Delta. The spectral characteristics of DOM in the water and sediment in this river were studied to examine their sources and characteristics. The DOM was analyzed by three-dimensional fluorescence spectroscopy (EEM) coupled with the parallel factor analysis (PARAFAC) model. The following results were noted. ① Four fluorescence DOM components were derived by EEM-PARAFAC:C1 represents terrestrial humus with a high molecular weight; C2 represents terrestrial humus with a low molecular weight, which was produced by biodegradation; C3 represents protein-like substances that were sensitive in a microenvironment; and C4 is terrestrial humus. ② Both new-born endogenous and terrestrial sources have large impacts on DOM components. The humification degree was very weak with a low concentration of humus. The DOM in the sediments was derived mainly from terrestrial or soil sources with small endogenous contribution with high humification. The concentration of humus in the sediments was significantly higher than that in water. ③ Redundancy analysis (RDA) showed that farmland and urban land use were the dominant environmental factors and had relatively high correlation with the water indicators. Construction land, farmland, and wetland land use positively correlated with the sediment components. Among them, urban land use had the greatest influence on the concentration parameter Fn(355) of humus-like substance C4 and the humus-like substance in sediments.

[Clinical analysis of 54 patients with non-syndromic enlarged vestibular aqueduct]

Objective:To further recognize the clinical characteristics of non-syndromic enlarged vestibular aqueduct through the retrospective analysis of cases, with the purpose of providing references for clinical diagnosis and treatment. Method:Collect 54 cases of non-syndromic enlarged vestibular aqueduct, and analyze their clinical characteristics after history taking, physical examination, audiometry and imaging examination. Measure the biggest width of midpoint between internal and external of vestibular aqueduct on temporal bone thin-section CT, and analyze the relationship between the pipe width and sides of ear, types of hearing loss and degree of hearing loss through t test. Result:All 54 patients with non-syndromic enlarged vestibular aqueduct had bilateral ear involvement. There were 42 cases with prelingual deafness, 12 cases with postlingual deafness, and there were 38 ears with severe deafness, 70 ears with profound deafness. Ninety-six ears of hearing loss showed sensorineural deafness, and 12 ears manifested mixed deafness. The biggest width of midpoint between internal and external of vestibular aqueduct spread over 1.60-3.90 mm, and the average was 2.60 mm. There were no significant differences in data between left and right sides, degree of hearing loss and type of hearing loss. Conclusion:Non-syndromic enlarged vestibular aqueduct mainly manifests serious sensorineural deafness, and the diagnosis depends on imaging examination. There is no difference in the degree of expanding between left and right ear, and the extent of enlargement is not related to the type and the severity of hearing loss.

Phosphorus and oxygen co-doped composite electrode with hierarchical electronic and ionic mixed conducting networks for vanadium redox flow batteries

The GF-TCN electrodes with excellent electrocatalytic activity and faster electron/ion conduction indicate outstanding rate capability and energy efficiency of VRFBs.

Shock wave propagation, plasticity, and void collapse in open-cell nanoporous Ta

We systematically investigate the wave propagation, plasticity and void collapse, as well as the effects of porosity, specific surface area and impact velocity, in a set of open-cell nanoporous Ta, during shock compression, via performing large-scale non-equilibrium molecular dynamics simulations. The shock wave propagation presents an impedance, sensitive to porosity, but not to specific surface area. Such surprising phenomena are due to the similar sensitivities in density and stress variations to porosity or specific surface area. Upon impact, shock front shapes change from ramped to steep ones, with increasing porosity, specific surface area or impact velocity, owing to the transition from the heterogeneous to homogeneous plasticity along transverse directions. This transition of plasticity arises by (i) the strong impedance on large deformation bands as porosity increases; and (ii) the transition from deformation twinning to dislocation slips, and to amorphization, as the specific surface area or impact velocity increases. Shock-induced plasticity, including their nucleation, growth and interactions, also facilitates the collapse of voids.

Surface premelting/recrystallization governing the collapse of open-cell nanoporous Cu via thermal annealing

We systematically investigate the collapse of a set of open-cell nanoporous Cu (np-Cu) materials with the same porosity and shape but different specific surface areas, during thermal annealing, by performing large-scale molecular dynamics simulations. Two mechanisms govern the collapse of np-Cu. One is direct surface premelting, facilitating the collapse of np-Cu, when the specific surface area is less than a critical value (∼2.38 nm-1). The other is recrystallization followed by surface premelting, accelerating the sloughing of ligaments and the annihilation of voids, when the critical specific surface area is exceeded. Surface premelting results from surface reconstruction by prompting localized "disordering" and "chaos" on the surface, and the melting temperature reduces linearly with the increase of the specific surface area. Recrystallization is followed by surface premelting as the melting temperature is below the supercooling point, where a liquid is unstable and instantaneously recrystallizes.

[Characteristics of Dissolved Organic Matter (DOM) and Relationship with Dissolved Heavy Metals in a Peri-urban and an Urban River]

Dissolved organic matter (DOM) is ubiquitous in the aquatic environment, playing an important role in the fate of heavy metals in aquatic systems. In this study, we characterized the DOM and heavy metals and their distribution in a peri-urban river and an urban river in Ningbo city. In addition, the relationship between DOM and dissolved heavy metals was also determined. Results showed that higher DOC, CDOM, and FDOM concentrations were found in the river with the higher urbanization level. Four fluorescence peaks were identified in the excitation-emission matrix (EEM) of DOM, including fulvic acid-like fluorescence peaks A and C and protein-like fluorescence peaks B and T. The higher fluorescence intensities of peak B and T were found in the urban river, and similar trends were also found for the degree of humification and aromaticity of DOM. Similarly, concentrations of heavy metals, such as As, Cu, and Mn, were significantly higher in the urban river. Moreover, DOM had significant positive correlations with Cu, Cr, Mn, As, Zn, and Pb in the urban river, while DOM only exhibited significant positive correlations with Mn, Pb, and Cu in the peri-urban river. In conclusion, urbanization level influenced the characteristics and concentrations of CDOM in rivers which were closely related to the distribution of heavy metals.

Biochars induced modification of dissolved organic matter (DOM) in soil and its impact on mobility and bioaccumulation of arsenic and cadmium

Biochar application has attracted great attention due to its diverse uses and benefits in the fields of environmental management and agriculture. Biochar modifies the composition of dissolved organic matter (DOM) in soil, which directly or indirectly controls the mobility of metal contaminants and their bioaccumulation. In this study, ten different hydrothermal biochars pyrolysed from mushroom waste (MSBC), soybean straw (SBBC), sewage sludge (SSBC), peanut shells (PNBC) and rice straw (RSBC) at two pyrolysis temperatures (200 °C and 350 °C) were used to investigate DOM changes in soil solution and their effects on metal availability and bioaccumulation. Biochar induced modification of soil DOM which was characterized by spectroscopic analysis of water soluble organic carbon, specific absorbance (SUVA₂₅₄), UV-vis absorption, spectral slope (S_R) and the absorption coefficient. Regarding rice plant growth, the biochar effects on biomass were greatly varied. Biochars (except for RSBC and MSBC) prepared at high temperature significantly (P ≤ 0.05) suppressed the availability of As and Cd in soil and their subsequent bioaccumulation in rice plants. The highest reduction (88%) in bioaccumulated As was observed in rice grown on soil amended with SBBC prepared at 350 °C (the highest temperature for hydrothermal technique). The addition of biochars (except RSBC and MSBC) prepared at high temperature markedly (p < 0.05) decreased AsIII (30-92%), while the effects on dimethylarsenic acid (DMA) and arsenate (AsV) concentrations were not significant except for SSBC350 (prepared at 350 °C) treatment. These results highlight the potential of biochar-DOM interactions as an important mechanism for suppressing the mobility and bioaccumulation of As and Cd in biochar-amended paddy agricultural systems.

[Fluorescent Dissolved Organic Matter and Its Correlation with Water Quality in a Urban River: A Case Study of the Lujiang River in Beilun, Ningbo]

Excitation-emission matrix fluorescence spectroscopy combined with fluorescence regional integration (FRI) analysis were adopted to analyze the water samples collected from the Lujiang River, which flows through the rapidly urbanizing areas of Beilun, Ningbo, in order to illuminate the composition and characteristics of the spatial distribution of fluorescent dissolved organic matter (FDOM), and further to explain its correlation with water quality in the urban river. The results showed that FDOM was composed of tyrosine-like, tryptophan-like, soluble microbial by-product-like, fulvic-like, and humic-like materials, and FDOM was dominated by protein-like components, accounting for 83.8% of the total fluorescence intensity, while humic-like components accounted for much less. The concentrations of the water quality parameters, such as total nitrogen, total phosphorus, and metals, were linearly correlated with the total fluorescence intensity of all components, indicating that FDOM was significantly related to the removal and transformation of nitrogen and phosphorus. The distribution of FDOM in different areas has the following characteristics:FDOM was low and not distinctly influenced by human activities in the upstream, while in the downstream, FDOM was high and showed the characteristics typical of that in urbanized rivers. Therefore, anthropogenic activities can greatly influence river water quality and the concentration and composition of FDOM.

Identification and expression analysis of terminal deoxynucleotidyl transferase in humphead snapper Lutjanus sanguineus

A tdt gene was identified successfully from humphead snapper Lutjanus sanguineus, which contained 1710 bp encoding a protein of 463 amino acids. Results of quantitative real-time polymerase chain reaction (qRT-PCR) indicated that tdt mainly expressed in thymus and head kidney and the transcripts of tdt in these tissues were up-regulated significantly at 36 and 48 h after Vibrio harveyi infection. Meanwhile Tdt-producing cells were found in thymus and head kidney.

Comparative RNA profile analysis of idiopathic dilated cardiomyopathy and ischemic cardiomyopathy

Previous research has focused on revealing the functions of each individual gene and/or pathway in idiopathic dilated cardiomyopathy (DCM) or ischemic cardiomyopathy (IC). However, the common or specific pathways of the initiation and processes of DCM and IC are still unclear. Here, we attempted to uncover the critical genes and potential molecular networks that play important roles in DCM and IC progression commonly or specifically. The transcriptional profiles from normal and DCM or IC patient samples were analyzed and compared using bioinformatic methods. Initially, the normal and DCM or IC sample data were processed and the most notable differentially expressed genes (DEGs) from DCM or IC were identified. By comparing the DEGs from DCM with those from IC, the DCM- and IC-specific DEGs were identified. The gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated the significance of multiple biological processes as well as signaling pathways that affect heart function and DCM or IC progression. Protein-protein interaction network analysis identified the relationships between different genes, and some important genes such as MYC and FN1 were found to be hubs, which master each individual module of DCM-specific and IC-specific DEGs, respectively. We discovered commonalities and differences of gene expression profiles and molecular pathways between different cardiomyopathies. The gene discovery and molecular signature analysis in this study could offer insights into disease mechanisms and also identify markers useful for diagnostic, prognostic, and therapeutic purposes.

Advances in the researches on the biological activities and inhibitors of phosphatidylinositol 3-kinase

The PI3K/AKT/mTOR pathway is an intracellular signaling pathway, being important in apoptosis hence cancer such as breast cancer and non-small-cell lung cancer. It signaling axis controls cell proliferation and survival and has achieved major importance as a target for cancer therapy. The serine/threonine kinase Akt (also known as protein kinase B or PKB), since its initial discovery as a protooncogene, has become a major focus of attention because of its critical regulatory role in diverse cellular processes, including cancer progression and insulin metabolism. The Akt cascade is activated by receptor tyrosine kinases, integrins, B and T cell receptors, cytokine receptors, G protein coupled receptors and other stimuli that induce the production of phosphatidylinositol 3,4,5 triphosphates (PtdIns(3,4,5)P3) by phosphoinositide 3-kinase (PI3K). Therefore, PI3K plays an important role in in numerous cellular functions such as cell growth, proliferation, differentiation, motility, survival and intracellular trafficking. In this review, we introduced the structure of the PI3K, and then focused on its biological activities. In addition, we reviewed the advances in the researches of PI3K as well as related inhibitors over the last couple of decades. Finally, we also discussed the prospect and developmental trend of phosphatidylinositol 3-kinase as antitumor agents.

Design, modification and 3D QSAR studies of novel naphthalin-containing pyrazoline derivatives with/without thiourea skeleton as anticancer agents

Two series of novel naphthalin-containing pyrazoline derivatives C1-C14 and D1-D14 have been synthesized and evaluated for their EGFR/HER-2 inhibitory and anti-proliferation activities. Compound D14 displayed the most potent activity against EGFR and A549 cell line (IC(50)=0.05 μM and GI(50)=0.11 μM), being comparable with the positive control Erlotinib (IC(50)=0.03 μM and GI(50)=0.03 μM) and more potent than our previous compounds C0-A (IC(50)=5.31 μM and GI(50)=33.47 μM) and C0-B (IC(50)=0.09 μM and GI(50)=0.34 μM). Meanwhile, compound C14 displayed the most potent activity against HER-2 and MCF-7 cell line (IC(50)=0.88 μM and GI(50)=0.35 μM), being a little less potent than Erlotinib (IC(50)=0.16 μM and GI(50)=0.08 μM) but far more potent than C0-A (IC(50)=6.58 μM and GI(50)=27.62 μM) and C0-B (IC(50)=2.77 μM and GI(50)=3.79 μM). The docking simulation was performed to analyze the probable binding models and the QSAR models were built for reasonable design of EGFR/HER-2 inhibitors at present and in future. The structural modification of introducing naphthalin moiety reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity. Moreover, the replacement of thiourea skeleton by using benzene ring resulted in the slight diversity of the two series towards specific targets.

Design, synthesis and biological evaluation of heterocyclic azoles derivatives containing pyrazine moiety as potential telomerase inhibitors

Three series of novel heterocyclic azoles derivatives containing pyrazine (5a-5k, 8a-8k and 11a-11k) have been designed, synthesized, structurally determined, and their biological activities were evaluated as potential telomerase inhibitors. Among the oxadiazole derivatives, compound 5c showed the most potent biological activity against SW1116 cancer cell line (IC(50)=2.46 μM against SW1116 and IC(50)=3.55 μM for telomerase). Compound 8h performed the best in the thiadiazole derivatives (IC(50)=0.78 μM against HEPG2 and IC(50)=1.24 μM for telomerase), which was comparable to the positive control. While compound 11f showed the most potent biological activity (IC(50)=4.12 μM against SW1116 and IC(50)=15.03 μM for telomerase) among the triazole derivatives. Docking simulation by positioning compounds 5c, 8h and 11f into the telomerase structure active site was performed to explore the possible binding model. The results of apoptosis demonstrated that compound 8h possessed good antitumor activity against HEPG2 cancer cell line. Therefore, compound 8h with potent inhibitory activity in tumor growth inhibition may be a potential antitumor agent against HEPG2 cancer cell. Therefore, the introduction of oxadiazole, thiadiazole and triazole structures reinforced the combination of our compounds and the receptor, resulting in progress of bioactivity.

Synthesis, biological evaluation and molecular docking studies of resveratrol derivatives possessing curcumin moiety as potent antitubulin agents

A series of resveratrol derivatives possessing curcumin moiety were synthesized and evaluated for their antiproliferative activity against three cancer cell lines including murine melanoma B16-F10, human hepatoma HepG2 and human lung carcinoma A549. Among them, compound C5 displayed the most potent in vitro antiproliferative activity against B16-F10 with IC(50) value of 0.71 μg/mL. Compound C5 also exhibited good tubulin polymerization inhibitory activity with IC(50) value of 1.45 μg/mL. Furthermore, docking simulation was carried out to position C5 into the tubulin-colchicine binding site to determine the probable binding mode.

Association of two glyoxalase I gene polymorphisms with nephropathy and retinopathy in Type 2 diabetes

BACKGROUND

Glyoxalase I (GLO1), which is the major enzyme that catalyzes the metabolism of methylglyoxal (MG), may play an important role in the pathogenesis of diabetic microvascular complications.

AIM

To investigate whether the C-7T and A419C polymorphisms of the GLO1 gene are associated with nephropathy and retinopathy in Chinese Type 2 diabetic patients.

SUBJECTS AND METHODS

A total of 364 Type 2 diabetic patients and 301 healthy controls were enroled in the study. Diabetic microvascular complications were determined by urinary albumin excretion measurements and ophthalmological examinations. Genetic analyses were performed using either Taqman PCR or direct sequencing. The effect of C-7T polymorphism on promoter activity was measured by reporter gene assays.

RESULTS

The albumin/ creatinine ratio (ACR) and prevalence of nephropathy and retinopathy were significantly higher in diabetic patients with GLO1 -7CC genotype than in patients with -7CT and -7TT genotypes (p=0.02, p=0.02, and p=0.04, respectively). The - 7CC genotype is independently associated with ACR (β=0.13, p=0.01) and the risk for retinopathy [odds ratio (OR): 2.30, 95% confidence interval (CI): 1.25-4.24, p<0.01]. The luciferase activity of the -7T promoter was higher than that of the -7C promoter (13.2±0.2 vs 11.7±0.8, p=0.04). No differences were found between ACR and the prevalence of nephropathy and retinopathy for A419C polymorphism in Type 2 diabetic patients.

CONCLUSIONS

GLO1 C-7T polymorphism alters promoter activity and confers susceptibility to nephropathy and retinopathy to Type 2 diabetic patients.

Synthesis, biological evaluation, and molecular docking studies of 1,3,4-oxadiazole derivatives possessing 1,4-benzodioxan moiety as potential anticancer agents

In present study, a series of new 1,3,4-oxadiazole derivatives containing 1,4-benzodioxan moiety (6a-6s) as potential telomerase inhibitors were synthesized. The bioassay tests demonstrated that compounds 6k, 6l, 6m, 6n and 6s exhibited broad-spectrum antitumor activity with IC(50) concentration range from 7.21 μM to 25.87 μM against the four cancer cell lines, HEPG2, HELA, SW1116 and BGC823. Moreover, all the title compounds were assayed for telomerase inhibition using the TRAP-PCR-ELISA assay. The results showed compound 6k possessed the most potent telomerase activity (IC(50)=1.27 ± 0.05 μM). Docking simulation was performed to position compound 6k into the active site of telomerase (3DU6) to determine the probable binding model.

Synthesis, biological evaluation, and molecular docking studies of resveratrol derivatives possessing chalcone moiety as potential antitubulin agents

Twenty-three resveratrol derivatives possessing chalcone moiety were synthesized and characterized, and their biological activities were also evaluated as potential antiproliferation and tubulin polymerization inhibitors. Compound C19 exhibited the most potent activity in vitro, which inhibited the growth of HepG2, B16-F10, and A549 cell lines with IC(50) values of 0.2, 0.1, and 1.4 μg/mL, respectively. Compound C19 also exhibited significant tubulin polymerization inhibitory activity (IC(50)=2.6 μg/mL). Docking simulation was performed to position compound C19 into the tubulin-colchicine binding site to determine the probable binding mode.

One hundred and one new microsatellite loci derived from ESTs (EST-SSRs) in bread wheat

Four hundred and seventy-eight microsatellite markers derived from expressed sequence tags (EST-SSRs) were screened among three mapping populations (W-7984xOpata 85, WOpop; LumaixHanxuan, LHpop; WenmaixShanhongmai, WSpop). The number of polymorphic EST-SSR primer pairs found in WOpop, LHpop and WSpop was 92, 58 and 29 respectively. A total of 101 EST-SSR loci amplified from 88 primer sets were distributed over the 20 chromosomes of the reference maps (no markers were located on chromosome 4B). These 101 mapped EST-SSR markers add to the existing 450 microsatellite loci previously mapped in bread wheat. Seventy-four of the 101 loci showed significant similarities to known genes, including 24 genes involved in metabolism, 4 in cellular structures, 9 in stress resistance, 12 in transcription, 2 in development, 2 transporters and 21 storage proteins. Besides gliadin and glutenin, most of the 53 genes with putative functions were mapped for the first time by EST-SSR markers in bread wheat. Sequence alignment of the mapped wheat EST-SSR loci allowed tentative assignment of functionality to the other members of grasses family. Colinearity combined with homology information offers an attractive approach to comparative genomics.

Low-voltage thin-film electroluminescent devices with low-resistivity stacked insulators

The characteristics and mechanism of low-voltage-driven thin-film electroluminescent (TFEL) devices with low-resistivity (10(6)-10(7)-ohms cm) SiO(2)/Ta(2)O(5) and Al(2)O(3)/Ta(2)O(5) stacked insulating films have been studied. At 50-Hz sinusoidal wave voltage excitation, the threshold voltage of devices with a ZnS:Mn emitting layer is below 40 V, and the brightness and luminous efficiency are above 1000 cd/m(2) and 4 lm/W, respectively, with 60 V voltage. The characteristics of brightness versus voltage (B-V) curves, integrated charge versus voltage (Q-V) figures, and luminous efficiency versus voltage (eta-V) characteristics are different from conventional devices. The study of a special semiconductor layer--a thin probe-doped layer located at a different part of the pure ZnS layer--has proved that the excitation efficiency is not homogeneous across the emitting layer in this kind of device, and its value decreases from the anode toward the cathode, which is opposite of that made with TFEL devices with high-resistivity insulators. By offering a model of space-charge-limited current, the mechanism of low-voltage-driven thin-film electroluminescence, its optoelectronic characteristics, and the distribution characteristics of excitation efficiency across the emitting layer can be thoroughly explained.

Estimation of optical constants of thin film by the use of artificial neural networks

A system for analyzing single-layer optical thin films has been formulated by the use of artificial neural networks. The training data sets stem from the computational results of the physical model of thin films, and they are used to train the artificial neural network, which, when done, can give values of film parameters in the millisecond time regime. The fast backpropagation algorithm is employed during training. The results of training are also given.

Infrared optical absorption loss of antireflection coatings on germanium and potassium chloride substrates at the 10-µm wavelength by the photothermal deflection technique

The photothermal deflection technique is used to study the infrared absorption of antireflection coatings on Ge and KCl substrates. The thin films deposited by the thermal resistance evaporation technique, both with and without ion-assisted deposition, are investigated. The experimental results show that Ar-ion bombardment with low energy can evidently reduce the absorption of the coatings.

[The effect of nifedipine on pulmonary hemodynamics after injection of oleic acid in rabbits]

Twelve rabbits were divided into two groups, A: control group; B: nifedipine group. Oleic acid (0.1 ml/kg) was injected into pulmonary arteries of 12 rabbits. Nifedipine (1 mg/kg) was given sublingually before oleic acid injected in B group. The results showed that the pulmonary vascular resistance (PVR), pulmonary artery pressure (PAP) were obviously increased and cardiac output (CO) heart rate (HR) decreased in two groups (P less than 0.05, P less than 0.01, P less than 0.001). The degree of increase of PVR, and the degree of decrease of CO were obviously less in B group than that of A group (P less than 0.05, P less than 0.01, P less than 0.001 in different periods). The results showed that nifedipine improved pulmonary hemodynamics of pulmonary damage by oleic acid.

Optimum design and preparation of multilayered magnetooptic recording media

A new computation of the optical performance of a magnetooptic multilayer structure has been developed, and the statistical testing method is used in the automatic design of multilayered MO recording media. With this method we have succeeded in preparing MO recording media with a bilayer structure. The prepared bilayer structures have excellent magnetic properties and their MO performance agrees well with theoretical predictions.

Properties of dielectric coatings produced by ion assisted deposition

Some metal oxides, fluorides, and ZnS films deposited by ion assisted deposition are investigated as a function of ion energy, ion variety, and ion source type. Both optical and mechanical properties, such as optical stability, absorption and scattering losses, laser damage threshold, and durability, are examined for samples deposited with the assistance of four kinds of ion source and various preparation conditions.

Characterization of thin film surfaces over an extended spatial wavelength range

The statistical properties of a thin film surface over an extended spatial wavelength have been studied by using the methods of differential scattering and digital analysis of replica micrographs. It can be concluded that, for a given film thickness, the surface features corresponding to long spatial wavelengths greater than several thousand angstroms are dominated mainly by the substrate surface, while the fine details corresponding to short spatial wavelengths are dominated by the thin film material and deposition process. Effects of ion-beam bombardment during deposition on surface roughness are also discussed.

Apparatus for wideband monitoring of optical coatings and its uses

A computer controlled rapid-scanning monochromator has been constructed for monitoring optical coatings in situ, determining the optical constants of films, and measuring the optical instability of filters. In this paper are given the main specifications of the apparatus, some results in the production of a number of broadband AR coatings, and characterization of some passband filters.

Transparent conducting indium doped ZnO films by dc reactive S-gun magnetron sputtering

Transparent conducting ZnO films have been prepared by modified S-gun reactive dc magnetron sputtering using an indium doped Zn target. Films with a resistivity of 1.08 x 10(-3) Omega cm and average transmittance of over 80% in the visible region were obtained. The influence of indium content at the surface of Zn target on the resistivity and transmittance of ZnO films was investigated. Optical properties of ZnO films in the 0.2-2.5-microm range were modeled by the Drude theory of free electrons. The reflectance of ZnO films in the 2.5-26.0-microm region was calculated.

Optical properties of extremely thin films: studies using ATR techniques

The optical constants and optical properties of extremely thin ZnS, SiO(2), Al, and Ag films are studied and compared by attenuated total reflection (ATR) techniques. The optical constants and optical absorptance as a function of film thickness are measured. The experimental results agree well with theoretical prediction. It is found that there is no discontinuity in optical constants and absorptance when an extremely thin layer changes from isolated islands to a continuous film for all the measured materials. The critical thicknesses at which they form continuous films show great differences for the various materials and deposition methods. The dependence of absorptance on thickness of extremely thin layers is studied experimentally and theoretically.

Measurement of weak absorption in optical thin films

An adiabatic laser calorimeter for measuring weak absorption in optical thin films is presented. It consists of three main parts which are used to control and measure temperature, and for calibration. The controlling temperature part is a set of automatic temperature controls mainly composed of a PID adjuster. The temperature difference between specimen and environment is always less than +/-0.006 degrees C during the measurement process. There is almost no energy exchange between specimen and environment. The specimen temperature increment is measured by a high precision thermistor set. Its measuring temperature sensitivity is 0.003 degrees C and the accuracy is +/-0.004 degrees C. The absolute electrical calibration part is used to obtain absorptance of a specimen immediately without needing to know the mass and specific heat of the specimen. Absorptance as small as 1 x10(-5) can be detected when a 1.5-W argon-ion laser is used.

New automatic design technique for optical coatings

A new automatic design method for optical thin-film systems is presented in which the effect of the errors in monitoring the optical multilayer coatings on the performance is considered. The merit function in the design involves both the optical properties and the calculated yield of finished products of the multilayer coatings. The highest yield of finished products is taken as an end optimization goal. The thin-film systems designed by this method not only satisfy the desired optical properties but also have larger manufacturing tolerances. Some examples of designs of broadband and double-band antireflection coatings are given.