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Liquid–liquid phase separation (LLPS) in organic aerosol particles can impact several properties of atmospheric particulate matter, such as cloud condensation nuclei (CCN) properties, optical properties, and gas-to-particle partitioning. Yet, our understanding of LLPS in organic aerosols is far from complete. Here, we report on the LLPS of one-component and two-component organic particles consisting of α-pinene- and β-caryophyllene-derived ozonolysis products and commercially available organic compounds of relevance to atmospheric organic particles. In the experiments involving single-component organic particles, LLPS was observed in 8 out of 11 particle types studied. LLPS almost always occurred when the oxygen-to-carbon elemental ratio (O:C) was ≤0.44 but did not occur when O:C was >0.44. The phase separation occurred by spinodal decomposition as well as the nucleation and growth mechanism, and when LLPS occurred, two liquid phases coexisted up to ∼100 % relative humidity (RH). In the experiments involving two-component organic particles, LLPS was observed in 23 out of 25 particles types studied. LLPS almost always occurred when the average was O:C ≤0.67 but never occurred when the average O:C was >0.67. The phase separation occurred by spinodal decomposition as well as the nucleation and growth mechanism. When LLPS occurred, two liquid phases coexisted up to ∼100 % RH. These results provide further evidence that LLPS is likely a frequent occurrence in organic aerosol particles in the troposphere, even in the absence of inorganic salts.

Research on the viscosity and phase state of aerosol particles is essential because of their significant influence on the particle growth rate, equilibration times, and related evolution of mass concentration as well as heterogeneous reactions. So far, most studies of viscosity and phase state have been focused on organic aerosol particles, yet data on how viscosity can vary when the organic materials are mixed with inorganic salts remain scarce. Herein, using bead-mobility and poke-and-flow techniques, we quantified viscosities at 293 ± 1 K for binary mixtures of organic material / H2O and inorganic salts / H2O, as well as ternary mixtures of organic material / inorganic salts / H2O over the atmospheric relative humidity (RH) range. Sucrose as the organic species and calcium nitrate (Ca(NO3)2) or magnesium nitrate (Mg(NO3)2) as the inorganic salts were examined. For binary sucrose / H2O particles, the viscosities gradually increased from ∼ 3 × 10−2 to ≳1 × 108 Pa s as RH decreased from ∼ 75 % to ∼ 25 %. Compared with the results for the sucrose / H2O particles, binary Ca(NO3)2/H2O and Mg(NO3)2/H2O particles showed drastic enhancements to ≳1 × 108 Pa s at low RH close to the efflorescence RH. For ternary mixtures of sucrose / Ca(NO3)2 / H2O or sucrose / Mg(NO3)2 / H2O, with organic-to-inorganic mass ratios of 1:1, the viscosities of the particles gradually increased from ∼ 3 × 10−2 to greater than ∼ 1 × 108 Pa s for RH values from ∼ 75 % to ∼ 5 %. Compared to the viscosities of the Ca(NO3)2/H2O particles, higher viscosities were observed for the ternary sucrose / Ca(NO3)2 / H2O particles, with values increased by about 1 order of magnitude at 50 % RH and about 6 orders of magnitude at 35 % RH. Moreover, we applied a thermodynamics-based group-contribution model (AIOMFAC-VISC, Aerosol Inorganic–Organic Mixtures Functional groups Activity Coefficients Viscosity) to predict aerosol viscosities for the studied systems. The model predictions and viscosity measurements show good agreement within ∼ 1 order of magnitude in viscosity. The viscosity measurements indicate that the studied mixed organic–inorganic particles range in phase state from liquid to semi-solid or even solid across the atmospheric RH range at a temperature of 293 K. These results support our understanding that organic / inorganic / H2O particles can exist in a liquid, semisolid, or even a solid state in the troposphere.

Secondary organic aerosols (SOAs), which are formed and transformed through complex physicochemical processes in the atmosphere, have attracted considerable attention over the past decades because of their impacts on both climate change and human health. Recently, 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a low volatile, highly oxidized, secondary generation product of monoterpenes, is one of the most relevant tracer compounds for biogenic SOAs. Therefore, MBTCA was selected to understand its hygroscopic properties better. In addition, interactions between the organic acid and inorganic components have been reported, which may alter their hygroscopic properties mutually. In this study, laboratory-generated, micrometer-sized, pure MBTCA, mono-/di-/tri-sodium MBTCA salts, and MBTCA-NaCl mixture aerosol particles of four mixing ratios (molar ratios = 1 : 1, 1 : 2, 1 : 3, and 2 : 1) were examined systematically to observe their hygroscopic behavior by varying the relative humidity (RH) from RH = ~95 % to ~1 % through a dehydration process, followed by a humidification process from RH = ~1 % to ~95 %, using in-situ Raman microspectrometry (RMS) assembled with a see-through impactor where the particles were deposited on a Si wafer. The hygroscopic behavior of pure MBTCA and MBTCA-NaCl mixture aerosol particles of three mixing ratios (molar ratios = 1 : 1, 1 : 2, and 1 : 3) were also examined using a levitation system mounted on in-situ RMS through a humidification process from RH = ~10 % to ~80 % after a quenching process from droplets, followed by dehydration from RH = ~80 % to ~10 %. The pure MBTCA droplets effloresced at RH = ~30–57.8 % and did not dissolve until RH > 95 %. The mono- and di-sodium MBTCA salt aerosols did not show clear efflorescence RH (ERH) and deliquescence RH (DRH). In contrast, the tri-sodium MBTCA salt exhibited ERH = ~44.4–46.8 % and DRH = ~53.1 %, during the hygroscopic experiment cycle. The mixture aerosols generated from solutions of MBTCA : NaCl = 1 : 1 and 2 : 1 showed no visible ERH and DRH in the see-through impactor because of the partial and total consumption of NaCl, respectively, through chemical reactions during the dehydration process. The mixture particles with a 1 : 1 molar ratio in the levitation system exhibited a clear DRH at ~71 % and ERH at ~50 %. This suggests less reaction between the mixtures and a larger portion of NaCl remaining in the levitation system. The other mixtures of MBTCA : NaCl = 1 : 2 and 1 : 3 displayed single-stage efflorescence and deliquescence at ERH = ~45–50 % and DRH = ~74 %, respectively, because of the considerable amount of NaCl present in the mixture aerosols in both systems. Observations and Raman analyses indicated that only monosodium MBTCA salt aerosols could be formed through a reaction between MBTCA and NaCl. The reaction occurred more rapidly with a more elevated concentration of either MBTCA or NaCl, and the controlling factor for the reactivity of the mixtures depended mostly on the availability of H+ dissociated from the MBTCA tricarboxylic acid. The lower degree of reaction of the mixture particles in the levitation system might be caused by the relatively airtight circumstance inside, i.e., the less release of HCl. In addition, the quenching process, i.e., the starting point of the hygroscopicity experiments, induced the solidification of MBTCA, and further, a slow reaction between MBTCA and NaCl. The study revealed that the interactions between the MBTCA and NaCl could modify the properties of the organic acid in the atmosphere, leading to enhanced capability of the probable heterogeneous chemistry in the aqueous aerosols.; 11 Secondary organic aerosols (SOAs), which are formed and transformed through complex 12 physicochemical processes in the atmosphere, have attracted considerable attention over the past decades 13 because of their impacts on both climate change and human health. Recently, 3-methyl-1,2,3-14 butanetricarboxylic acid (MBTCA), a low volatile, highly oxidized, secondary generation product of 15 monoterpenes, is one of the most relevant tracer compounds for biogenic SOAs. Therefore, MBTCA was 16 selected to understand its hygroscopic properties better. In addition, interactions between the organic acid 17 and inorganic components have been reported, which may alter their hygroscopic properties mutually. In 18 this study, laboratory-generated, micrometer-sized, pure MBTCA, mono-/di-/tri-sodium MBTCA salts, 19 and MBTCA-NaCl mixture aerosol particles of four mixing ratios (molar ratios = 1:1, 1:2, 1:3, and 2:1) 20 were examined systematically to observe their hygroscopic behavior by varying the relative humidity 21 (RH) from RH = ~95% to ~1% through a dehydration process, followed by a humidification process from 22 RH = ~1% to ~95%, using in-situ Raman microspectrometry (RMS) assembled with a see-through 23 impactor where the particles were deposited on a Si wafer. The hygroscopic behavior of pure MBTCA 24 and MBTCA-NaCl mixture aerosol particles of three mixing ratios (molar ratios = 1:1, 1:2, and 1:3) were 25 also examined using a levitation system mounted on in-situ RMS through a humidification process from 26 2 RH = ~10% to ~80% after a quenching process from droplets, followed by dehydration from RH = ~80% 27 to ~10%. The pure MBTCA droplets effloresced at RH = ~30-57.8% and did not dissolve until RH > 28 95%. The mono-and di-sodium MBTCA salt aerosols did not show clear efflorescence RH (ERH) and 29 deliquescence RH (DRH). In contrast, the tri-sodium MBTCA salt exhibited ERH = ~44.4-46.8% and 30 DRH = ~53.1%, during the hygroscopic experiment cycle. The mixture aerosols generated from solutions 31 of MBTCA:NaCl = 1:1 and 2:1 showed no visible ERH and DRH in the see-through impactor because of 32 the partial and total consumption of NaCl, respectively, through chemical reactions during the 33 dehydration process. The mixture particles with a 1:1 molar ratio in the levitation system exhibited a clear 34 DRH at ~71% and ERH at ~50%. This suggests less reaction between the mixtures and a larger portion 35 of NaCl remaining in the levitation system. The other mixtures of MBTCA:NaCl = 1:2 and 1:3 displayed 36 single-stage efflorescence and deliquescence at ERH = ~45-50% and DRH = ~74%, respectively, because 37 of the considerable amount of NaCl present in the mixture aerosols in both systems. Observations and 38 Raman analyses indicated that only monosodium MBTCA salt aerosols could be formed through a 39 reaction between MBTCA and NaCl. The reaction occurred more rapidly with a more elevated 40 concentration of either MBTCA or NaCl, and the controlling factor for the reactivity of the mixtures 41 depended mostly on the availability of H + dissociated from the MBTCA tricarboxylic acid. The lower 42 degree of reaction of the mixture particles in the levitation system might be caused by the relatively 43 airtight circumstance inside, i.e., the less release of HCl. In addition, the quenching process, i.e., the 44 starting point of the hygroscopicity experiments, induced the solidification of MBTCA, and further, a 45 slow reaction between MBTCA and NaCl. The study revealed that the interactions between the MBTCA 46 and NaCl could modify the properties of the organic acid in the atmosphere, leading to enhanced 47 capability of the probable heterogeneous chemistry in the aqueous aerosols. 48 49

A novel wideband and high gain dual-polarized antenna with log-periodic parasitic directors is presented in this paper. The antenna is composed of two cross printed dipole antennas vertically fixed on an aluminum plate as ground plane, which are excited by two similar micro-strip baluns. In order to further improve the gain with a broad bandwidth, the log-periodic parasitic directors are loaded on the printed dipole antennas innovatively. Measured results show that the proposed antenna achieves a –10 dB return loss with bandwidth of 1–2.1 GHz (71%), and its port isolation is higher than –20 dB within that band. Furthermore, the average gain of antenna is improved by 3 dB because of LPPDs.

Co-gasification of coal and biomass is an effective way to utilize coal of low rank to alleviate problems of energy shortage and environmental pollution. In order to investigate the product distribution resulting from the co-gasification of coal and biomass in a fluidized-bed reactor, experiments were conducted at varying biomass ratios, oxygen equivalent ratios, steam/carbon ratios, and also gasification temperatures. With an increase of biomass ratio, the amount of CO and CH4 increased while H2 and CO2 contents decreased. The amount of H2 increased obviously with an increase of gasification temperature ranging from 650 to 1000°C, whereas the CO and CO2 amount decreased. An increase of the steam/carbon ratio was beneficial to promote H2 formation and decrease CO and hydrocarbon compounds. With an increase of the gasification temperature, the steam/carbon ratio and oxygen equivalent ratio can promote the elements with low reaction activity in biomass gasification to be useful gas compositions.

The traditional phase field method adopts periodic boundary conditions and thus can only be applied to a continuous medium. In this manuscript, an extended phase field model is developed to simulate the polarization switching in a finite ferroelectric body with free surfaces. The void region outside the ferroelectric body was modeled as an elastic body having the same elastic stiffness as the ferroelectrics as well as properly distributed eigenstrain which functions to satisfy the traction-free boundary condition. Based on this scheme, periodic boundary conditions can be applied to the discrete system including a finite ferroelectric body and the voids outside. The elastically inhomogeneous system can be solved easily. This model has high calculation efficiency and can be conveniently applied to finite ferroelectric bodies with arbitrary boundaries. Finally, the domain pattern formation in a ferroelectric nano-particle is simulated. The obtained polarization pattern and stress field are illustrated.

The present study examined the durability of face-slab concrete in concrete-faced rock-filled dams. The durability of face-slab concrete can be improved by optimising the amount of fly ash in the cement mixture. Durability tests, including permeability, abrasion resistance, repeated wetting and drying and repeated freezing and thawing, were conducted for face-slab concrete using different amounts of fly ash and polypropylene fibre. When the effect of the fly ash content on the concrete durability was evaluated, the results showed that a 20% fly ash content yielded an optimum durability level for concrete-faced rock-filled dams

The softening response properties of plain concrete, which directly affect the structural capacity of the concrete containment building of nuclear power plants, were studied via direct tension tests using large-size concrete specimens with two notches. A variation of two and three levels of the concrete strength and the maximum size of coarse aggregate, respectively, was considered. Two independently controlled actuators were used to ensure a homogeneous increase of crack mouth opening displacement (CMOD) on the top and bottom notches of the specimen and to avoid secondary flexural stresses. From the tests, the complete load–CMOD responses with stable post-peak descending curves were obtained for each specimen. The fracture energy data obtained using the complete load–CMOD responses and one evaluated using a classical prediction equation were compared. The results, owing to size effect, indicated that the fracture energy obtained in the current investigation is larger on average than that obtained using a classical prediction equation. The direct tensile strength of the large-size specimens was, however, about half the splitting tensile strength of the cylindrical specimens.

Ferroelectric and ferromagnetic materials have wide engineering applications. The defects and size effects are important reliability and sensitivity issues in the application of such materials. In this paper, phase field simulations were carried out to study the effects of cracks in ferroelectrics and size effects on ferromagnetics. In the former simulation, the crack tip domain switching regions and stress fields were plotted. The results obtained showed that a negative electric field tends to open the crack, whereas a positive field tends to close it. In the latter simulation, it was found that both the hysteresis and coercivity were greatly affected by the ratio of the characteristic length to domain wall width.

Waste activated sludge was aerobically treated to demonstrate multiple uses such as cultivating an oil degrading bacterial consortium; studying the influence of a bulking agent (peat moss) and total petroleum hydrocarbon concentration on bacterial growth and producing a soil conditioner using waste activated sludge. After 30 days of incubation, the concentration of oil-degrading bacteria was 4.3 x 10(8) CFU g(-1) and 4.5 x 10(8) CFU g(-1) for 5 and 10 g of total petroleum hydrocarbon, respectively, in a mixture of waste activated sludge (1 kg) and peat moss (0.1 kg). This accounts for approximately 88.4 and 91.1%, respectively, of the total heterotrophic bacteria (total-HB). The addition of bulking agent enhanced total-HB population and total petroleum hydrocarbon-degrading bacterial population. Over 90% of total petroleum hydrocarbon degradation was achieved by the mixture of waste activated sludge, bulking agent and total petroleum hydrocarbon. The results of physico-chemical parameters of the compost (waste activated sludge with and without added peat moss compost) and a substantial reduction in E. coli showed that the use of this final product did not exhibit risk when used as soil conditioner. Finally, the present study demonstrated that cultivation of total petroleum hydrocarbon-degrading bacterial consortium and production of compost from waste activated sludge by aerobic treatment was feasible.

Aspergillus fumigatus CY018 was recognized as an endophytic fungus for the first time in the leaf of Cynodon dactylon. By bioassay-guided fractionation, the EtOAc extract of a solid-matrix steady culture of this fungus afforded two new metabolites, named asperfumoid (1) and asperfumin (2), together with six known bioactive compounds including monomethylsulochrin, fumigaclavine C, fumitremorgin C, physcion, helvolic acid and 5,8-epidioxy-ergosta-6,22-diene-3-ol as well as other four known compounds ergosta-4,22-diene-3-ol, ergosterol, cyclo(Ala-Leu) and cyclo(Ala-Ile). Through detailed spectroscopic analyses including HRESI-MS, homo- and hetero-nuclear correlation NMR experiments (HMQC, COSY, NOESY and HMBC), the structures of asperfumoid and asperfumin were established to be spiro-(3-hydroxyl-2,6-dimethoxyl-2,5-diene4-cyclohexone-(1,3 � )-5 � -methoxyl-7 � -methyl-(1 � H, 2 � H, 4 � H)-quinoline-2 � ,4 � -dione) and 5-hydroxyl-2-(6-hydroxyl-2-methoxyl4-methylbenzoyl)-3,6-dimethoxyl-benzoic methyl ester, respectively. All of the 12 isolates were subjected to in vitro bioactive assays against three human pathogenic fungi Candida albicans, Tricophyton rubrumand Aspergillus niger. As a result, asperfumoid, fumigaclavine C, fumitremorgin C, physcion and helvolic acid were shown to inhibit C. albicans with MICs of 75.0, 31.5, 62.5, 125.0 and 31.5g/mL, respectively. © 2004 Elsevier B.V. All rights reserved.

Type III secretion systems identified in bacterial pathogens of animals and plants transpose effectors and toxins directly into the cytosol of host cells or into the extracellular milieu. Proteins of the type III secretion apparatus are conserved among diverse and distantly related bacteria. Many type III apparatus proteins have homologues in the flagellar export apparatus, supporting the notion that type III secretion systems evolved from the flagellar export apparatus. No type III secretion apparatus genes have been found in the complete genomic sequence of Campylobacter jejuni NCTC11168. In this study, we report the characterization of a protein designated FlaC of C. jejuni TGH9011. FlaC is homologous to the N- and C-terminus of the C. jejuni flagellin proteins, FlaA and FlaB, but lacks the central portion of these proteins. flaC null mutants form a morphologically normal flagellum and are highly motile. In wild-type C. jejuni cultures, FlaC is found predominantly in the extracellular milieu as a secreted protein. Null mutants of the flagellar basal rod gene (flgF) and hook gene (flgE) do not secrete FlaC, suggesting that a functional flagellar export apparatus is required for FlaC secretion. During C. jejuni infection in vitro, secreted FlaC and purified recombinant FlaC bind to HEp-2 cells. Invasion of HEp-2 cells by flaC null mutants was reduced to a level of 14% compared with wild type, suggesting that FlaC plays an important role in cell invasion.

To investigate the effect of targeted antiosteosarcoma methotrexate-bisphosphonate conjugate on growth inhibition and apoptosis in human osteosarcoma MG-63 cells.MG-63 cells were treated with various concentrations of methotrexate-bisphosphonate conjugate and apoptosis was monitored via an MTT assay, cell morphology, TUNEL assay and flow cytometry analysis.The survival rate of MG-63 cells treated for 24 to 96 hours with 2000 mg/ml or more of methotrexate-bisphosphonate conjugate decreased significantly. Cells treated with conjugate showed typical apoptotic features using inverted phase contrast microscopy and fluorescence staining, and the majority of cells demonstrated a positive result in the TUNEL assay. Karyopyknosis and crescent aggregation of chromatin were observed in conjugate-treated cells by electron microscopy. Flow cytometry of MG-63 cells treated with methotrexate-bisphosphonate conjugate showed a time and dose-dependent increase in apoptosis (p0.05).A targeted antiosteosarcoma methotrexate-bisphosphonate conjugate induces apoptosis in human osteosarcoma MG-63 cells. This new conjugate is a valuable experimental tool for the therapy of osteosarcoma.

Titanium nitride (TiN) films were deposited on 304 stainless steel substrate by hollow cathode discharge (HCD) ion-plating technique. The preferred orientation and microstructure were studied by x-ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. Microhardness of the TiN film was measured and correlated to the microstructure and preferred orientation. The results of TEM study showed that the microstructure of TiN film contains grains with nanometer scale. As the film thickness increases, the grain size of TiN increases. The x-ray results show that TiN(111) is the major preferred orientation of the film. The hardness of TiN film is primarily contributed from TiN(111) preferred orientation.

In this article, the correlation between the local stress distributions and the average stresses obtained by X-ray measurement is studied through numerical modeling. The finite element method (FEM) is used to simulate the local stress distributions within a three-dimensional random aggregate of anisotropic and isotropic single crystals under uniaxial elastic tension. The local stresses are calculated for polycrystalline W, Al, or Cu slabs with the same geometry and crystallite distribution. The stress/strain values in the crystallites that satisfy the diffraction condition are then used to simulate the X-ray data that would be obtained if the diffraction peaks from such aggregates were actually measured. In particular, the 200, 222, and 420 reflections are analyzed. The correlations between the far-field stress, the local stresses, and the average stresses determined through X-ray analysis are presented.

The aim of the paper is to evaluate the efficacy of CyberKnife® for the treatment of primary or metastatic retroperitoneal tumours. Twenty-eight patients were treated. The prescription isodose line (median, 78%; range, 70-84%) covered the planning target volume at a total dose of 2000-6000 cGy (median, 4500 cGy) and a biologically effective dose of 3750-10,080 cGy (median, 7680 cGy) in 2-10 fractions (median, five fractions). The results showed that the complete response, partial response, stable disease, and progressive disease rates were 43% (12/28), 36% (10/28), 18% (5/28), and 4% (1/28) respectively. The overall response rate was 96%. The 1-, 2- and 3-year local control rates were 92%, 86%, and 86% respectively. The 1-, 2- and 3-year overall survival rates were 60%, 49%, and 49% respectively. No significant difference was found between local progression-free survival and overall survival. Moreover, if a patient only had metastases in the retroperitoneum and local control was effective, there was no significant difference between local progression-free survival and overall progression-free survival. In conclusion, CyberKnife treatment for retroperitoneal tumours resulted in high response rates with minimal side effects. All radiation-induced side effects were well tolerated.

A biotin-labeled in situ hybridization technique was used in order to physically map RFLP markers to the chromosomes of rice (Oryza sativa L.). Fourteen RFLP markers, associated with the ends of the linkage groups on rice chromosomes 7, 8, 11, 12, were physically mapped onto specific regions of the chromosomes. The average detection rate of in situ hybridization was 5.91%. The markers were located on seven different chromosome arms. Ten of the fourteen markers were distributed near the chromosome ends. This demonstrated that the RFLP linkage groups involved covered a wide physical distance and that the centromeric region was bisected by all but one linkage group. Two markers covered a short genetic distance but were physically distant, while two covering a longer genetic distance were physically closer together. This indicates that considerable variation can, and does, exist between genetic and physical maps.This paper is a contribution of the U.S. Department of Agriculture, Agricultural Research Service, and Missouri Agricultural Experiment Station, Journal Series No. 11 882All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap.

By co-ammonolysis of MeHSiCI2 and Me2SiCl2 and following thermal polymerization, polysilazanes as the precursors to Si3N4/SiC ceramic fibre were synthesized. The tendency to cross-link in thermal polymerization is suppressed as the result of the introduction of Me2SiCl2 as a starting material. The reactions occurring during thermal polymerization of ammonolysis products are discussed based on infrared (i.r.) and 1H nuclear magnetic resonance (NMR) spectra analysis. The pyroiysis process of polysilazanes is examined in nitrogen and in an NH3 atmosphere. It is shown that the formation of SiC results from the pyrolysis of Si-CH3 groups in polysilazanes by means of the formation of Si-CH2-Si intermediate bonds. The structure and properties of ceramics derived from the pyrolysis of polysilazane and polycarbosilane in N2 or NH3 atmosphere are compared and discussed. Si-N-C ceramic, which was proved to be a composite of α-Si3N4 and β-SiC, exhibits better thermal stability at temperatures higher than 1300°C.

In a previous study [1], we prepared a kind of vinylcontaining precursor by introducing cyclomethylvinylsilazane (MVCSZ) to the polycarbosilanes (PCSs). The results showed that vinyl can enhance the irradiation curing of PCSs and a vinyl content of 2.33 wt% in PCS can lower its gel dose (curing dose) from 10 MGy (15 MGy) to 0.5 MGy (5 MGy), respectively. In order to observe the mechanical properties of soobtained low-oxygen-content SiC fiber from the vinylcontaining polycarbosilanes (Vi-PCSs), this paper studied the pyrolysis of uncured, EB-cured and aircured Vi-PCS precursors. Bundles of the green Vi-PCS fibers with a vinyl content of 2.33 weight percent were irradiated in helium atmosphere in a quartz vessel under an electron accelerator with a rate close to 0.8 MGy per min. The absorbed dose was 5.0 MGy. Afterwards, the samples were annealed in helium gas flow at 130 ◦C for 1 h and irradiation cross-linked Vi-PCS fibers were finally obtained. Another batch of the same green Vi-PCS fibers was air-cured in a furnace with air flowing through, up to 190 ◦C for 2 h with a weight gain of 10 wt%. The EB-cured or air-cured fibers were then pyrolyzed under a flow of high-purity nitrogen (Q = 10−5 m3/ min, P = 100 kPa) up to 1200 ◦C for 30 min with a relatively slow heating rate (100 ◦C/h). After this treatment, the fibers that were no longer sensitive to oxidation could be handled in air. The high temperature treatment was then achieved with a pyrolysis equipment comprising a graphite crucible with a radio frequency coil. The samples were heated (30 ◦C/min) and maintained at the pyrolysis temperature Tp under a high-purity nitrogen atmosphere (100 kPa) for tp = 30 min. The fibers were characterized by the following ways. Thermogravimetric analysis (TGA) (Rigaku, Japan) was performed, up to 1200 ◦C, in platinum crucibles on about 10 mg samples under a high-purity nitrogen flow (flow rate: 4 × 10−5 m3/min) with a temperature increase rate of 10 ◦C/min. The weight loss before and after high temperature treatment was measured and calculated with an analytical balance. Elemental (Si,C,N) analyses were performed on the samples by a chemical-analysis process. Oxygen contents were determined by a nitrogen/oxygen analyzer (TC-436, LECO, America). X-ray diffraction (XRD) spectra (Cu-Ka/Siemens D500 diffractometer, Germany) were recorded from tows of fibers for Tp = 1600 ◦C. The apparent mean grain size (L) of the β-SiC crystalline phase present in the samples was calculated from the width (D) of the (111) diffraction peak at mid-height, according to the following Equation 1

On etudie la synthese de polytitanocarbosilanes (PTC) de differents rapports atomiques Ti/Si a partir de tetrabutoxyde de titane et de polycarbosilane. On examine l'influence du rapport molaire de ces deux composes sur la structure et les proprietes des PTC utilises pour la preparation de fibres ceramiques par pyrolyse

A highly sensitive sodium (Na+) transfer tissue biosensor (STTB) was designed using a frog bladder membrane to measure paralytic shellfish poisons (PSP). The STTB consists, of a Na+ electrode covered by the membrane, which was then integrated into a flow-through system for continuous measurements. In the absence of Na+ channel blocker, active transfer of Na+ occurred from inside to outside across the frog membrane. When the STTB was used to measure the Na+ -dependent dissociation of PSP, it was able to detect PSB at a level contained in a single cell. However, 5 fg or higher (100 cells or more) is needed for accurate and reproducible measurements. The toxicity obtained by the STTB was significantly correlated (r = 0.9449) to that determined by the HPLC. Therefore, the simple method of the STTB can be used not only to detect a low level PSP in toxic plankton populations, but also to monitor poisons in shellfish.

YCP, a mitogenic polysaccharide with its molecular weight (MW) of 2.4 x 10(3) kDa, was isolated from the mycelium of the marine filamentous fungus Phoma herbarum YS4108 by a combination of ion-exchange chromatography on DEAE-32 and gel permeation over Sephacryl S-400. The detailed compositional, spectroscopic and methylation analyses of the polysaccharide demonstrated that its backbone possessed most likely a linear alpha-(1 --4) bonded glucopyranoside main chain co-bearing through side alpha-(1 --6)-linkage. The alpha-(1 --4) bondage of the glucopyranoside building blocks in YCP was confirmed by the observation that it could be hydrolyzed by the alpha-amylase produced by Bacillus licheniformis. A reliable concentration monitoring experimentation highlighted that the reducing sugars released continuously from YCP during its incubation with the enzyme, and the MW of the main resulting fragment weighed 0.8 x 10(4) Da with approximately 10% of YCP converted to maltose, maltotriose and glucose after a 120-min enzymatic degradation. Finally, YCP was found to be able to increase phagocytic activity of mice in vitro and in vivo, indicating that it may be looked up as a potent immunomodulator that could activate macrophages.

Type III secretion systems identified in bacterial pathogens of animals and plants transpose effectors and toxins directly into the cytosol of host cells or into the extracellular milieu. Proteins of the type III secretion apparatus are conserved among diverse and distantly related bacteria. Many type III apparatus proteins have homologues in the flagellar export apparatus, supporting the notion that type III secretion systems evolved from the flagellar export apparatus. No type III secretion apparatus genes have been found in the complete genomic sequence of Campylobacter jejuni NCTC11168. In this study, we report the characterization of a protein designated FlaC of C. jejuni TGH9011. FlaC is homologous to the N- and C-terminus of the C. jejuni flagellin proteins, FlaA and FlaB, but lacks the central portion of these proteins. flaC null mutants form a morphologically normal flagellum and are highly motile. In wild-type C. jejuni cultures, FlaC is found predominantly in the extracellular milieu as a secreted protein. Null mutants of the flagellar basal rod gene (flgF) and hook gene (flgE) do not secrete FlaC, suggesting that a functional flagellar export apparatus is required for FlaC secretion. During C. jejuni infection in vitro, secreted FlaC and purified recombinant FlaC bind to HEp-2 cells. Invasion of HEp-2 cells by flaC null mutants was reduced to a level of 14% compared with wild type, suggesting that FlaC plays an important role in cell invasion.

As the sewerage system is incomplete, sewage in Korea lacks easily biodegradable organics for nutrient removal. In this country, about 11,400 tons of food waste of high organic materials is produced daily. Therefore, the potential of food waste as an external carbon source was examined in a pilot-scale BNR (biological nutrient removal) process for a half year. It was found that as the supply of the external carbon increased, the average removal efficiencies of T-N (total nitrogen) and T-P (total phosphorus) increased from 53% and 55% to 97% and 93%, respectively. VFAs (volatile fatty acids) concentration of the external carbon source strongly affected denitrification efficiency and EBPR (enhanced biological phosphorus removal) activity. Biological phosphorus removal was increased to 93% when T-N removal efficiency increased from 78% to 97%. In this study, several kinds of PHAs (poly-hydroxyalkanoates) in cells were observed. The observed PHAs was composed of 37% 3HB (poly-3-hydroxybutyrate), 47% 3HV (poly-3-hydroxyvalerate), 9% 3HH (poly-3-hydroxyhexanoate), 5% 3HO (poly-3-hydroxyoctanoate), and 2% 3HD (poly-3-hydroxydecanoate).

Synthesis of substantially polycrystalline silicon carbide fibre, which has excellent mechanical properties and heat resistance, has been reported. Such a silicon carbide fibre can be prepared from preceramic polymers [1, 2]. Usually, the synthesis of precursor polycarbosilane (PC) was at high temperature and under high pressure. Then, in the synthesis process, polyborodiphenylsiloxane (PBSO) was used as a reaction catalyst [3-5], which is prepared from the slow, complex reaction between boric acid and diphenyldichlorosilane. In our experiment, polycarbosilane precursor containing titanium was obtained by the reaction between titanium tetrabutoxide [Ti(OBu)4] and liquid polysilane (LPS), which was derived from destructive distillation of polysilane (PS) in nitrogen gas [6]. Therefore, a similar reaction between boron tributoxide [B(OBu)3 ] and LPS was carried out in order to prepare polycarbosilane containing boron. The experimental results show that it seems to be difficult to introduce B(OBu)3 into the molecular structure of polycarbosilane, but the increase of molecular weight of polycarbosilane is accelerated remarkably in the presence of B(OBu)3. Evidently, the troublesome preparation process of PBSO can be eliminated by replacement of PBSO with B(OBu)3 as a catalyst. In the present work, the synthesis of polycarbosilane from LPS and B(OBu)3 according to different weight ratios is reported. The effects of B(OBu)3 on the structure and properties of polycarbosilane products are discussed. B(OBu)3 and LPS derived from destructive distillation in nitrogen gas up to 420 °C were mixed in certain weight ratios in a three-necked flask equipped with a quartz reactor tube, a recycling system and a thermometer. The mixtures were heated slowly in a nitrogen gas flow to a given temperature and the reaction proceeded at this temperature for 1 h, then the products were dissolved in toluene. After filtering and distillation, PC as a yellow solid was obtained. The infrared (IR) spectra of products were measured using a Hitachi 270-30 infrared spectrophotometer. The solid samples were measured by the KBr pellet method and the samples obtained at different t e m p e ~ e s during the reaction process were measured with a fixed-thickness (0.2 ram) cell of KBr in CC14 solution. The munber average molecular weights (Mn) and molecular weight distributions were measured using a Watters-244 liquid chromatograph with Ultrastyragel as the gel permeation chromatography (GPC) column in toluene solution. The melting points (Tm) were obtained with a melting point apparatus (model HMK, Germany). LPS can be regarded as a mixture of cyclic and linear low molecular weight polysilane, and its structure is assumed to be [6]

Using fluorescence in situ hybridization (FISH) with metaphase preparations, we localized a transferred barnase-psl DNA sequence onto chromosomes in 8 rice transgenic plants. All the tested rice transgenic lines showed hybridization signals on the middle and terminal regions of chromosome arms except for those close to centromeres. In two lines, two different integration sites were identified, and the other lines showed only one integration site. With the aid of Southern analysis and expression detection, we found that the barnase tended to show a higher level expression in the lines whose integration sites near the distal regions of chromosomes, while the expression level became lower in the lines whose integration sites near the centromeres. This result suggested a possible relationship between chromosomal location of transgenes and the expression level. However it showed no obvious relationship between copy numbers and expression levels. In most cases, the results of multi-color FISH showed that barnase-ps1 always integrated at the same position on the chrmosome as the reporter genes(pHctinG).

Multi-step sequential batch two-phase anaerobic composting (MUSTAC) process was used to recover methane and composted material from food waste. The MUSTAC process consists of five leaching beds for hydrolysis, acidification and post-treatment, and an upflow anaerobic sludge blanket (UASB) reactor for methane recovery. This process involves the combined methods of sequential batch operation and two-phase anaerobic digestion for simple operation and high efficiency. Rumen microorganisms are inoculated due to their enhanced cellulolytic activity. Each leaching bed is operated in a sequential batch mode. Five leaching beds are operated in a multi-step mode with a two-day interval between degradation stages. Acidified products in the leachate from the leaching beds are converted to methane in the UASB reactor. The MUSTAC process demonstrated that it was capable of removing 84.9% of volatile solids (VS) and converting 85.6% of biochemical methane potential (BMP) into methane at 10.9 kg VS/m3 x d in 10 days. Methane gas production rate was 2.31 m3/m3 x d. The output from the post-treatment of residues in the same leaching bed without troublesome moving met the Korean regulation on compost, indicating that it could be used for soil amendment.

Proto-oncogene ras is an important gene for suppress the animal cells apoptosis. To analyze the presence of homologous sequences of ras in maize and rice, Southern blot hybridization was performed and positive signals was detected in these two species' genomes. The physical location of the ras homologous sequences was also carried out in maize chromosome by FISH. ras was hybridized onto the long arm of the chromosomes 2 and 7. The detection rates of FISH were 10.85% and 14.15%, and percentage distances from centromere to detection sites were 54.92 +/- 1.90 and 94.62 +/- 2.77 respectively. These results provided important clues of the further research of plant apoptosis.

Peroxidase plays a key role in plant disease resistance, cold stress and some developmental processes, and cold-regulated protein functions necessarily in reaction of plants on cold or heat stress. Recent studies showed that these processes in plant cells were involved in programmed cell death (PCD). Using a biotin-labelled in situ hybridization (ISH) technique, we physically mapped the genes px and cld coding peroxidase and cold-regulated protein respectively onto maize chromosomes. Both DAB and fluorescence detection systems gave the identical results, the probe uaz235 corresponding to gene px was localized onto the long arm of chromosome 2 (2L) and 7L, and csu19 corresponding to gene cld was hybridized onto 4L and 5L. The percentage distances (from the hybridization sites to centromeres) of uaz235 in 2L and 7L were 45.4 +/- 1.3 and 67.4 +/- 3.7 respectively, and those of csu19 in 4L and 5L were 68.6 +/- 2.6 and 58.2 +/- 1.6 respectively. The physical positions of px in 2L and cld in 4L coincide with those in their genetic map pattern. The results also show that both of these genes have duplicated sites in maize genome.

Cryopreserved valve homografts often fail in infants. Controversies are ongoing concerning the relative contributions of cryopreservation variables, immune responses, cellular viability, and durability of the extracellular matrix to the mode of tissue failure.Tissues to be examined for patterns of ice crystal distribution were cryopreserved. Tissue water was substituted with methanol and the tissues cryopreserved conventionally using dimethylsulfoxide, after which they were warmed and processed for light or electron microscopy. Selected specimens were vitrified to prevent ice crystal formation, cryopreserved, and subsequently warmed and processed for light and electron microscopy.Cryosubstitution of conventionally cryopreserved heart valves, while still frozen, demonstrated extensive extracellular ice formation, with smaller crystals in the ventricularis than in either the spongiosa or fibrosa. Extracellular ice formation was prevented by vitrification, a process in which the biological system is stabilized as an amorphous solid in the absence of crystalline ice.It is proposed that the extensive ice formation observed in conventionally cryopreserved heart valves may cause extracellular matrix damage that predisposes the valves to calcification. Future studies will assess the above hypothesis by comparison of conventional and ice-free (vitrification) cryopreservation methods in animal models of calcification.

A unified lossless and lossy compression algorithm is proposed using integer-based reversible wavelet transforms. The proposed algorithm is based on improved pre-quantization, integer-based wavelet transform, and bit plane coding of wavelet bands with QM coder. From simulation, reconstructed image by the proposed algorithm shows higher peak signal-to- noise ratio (PSNR) compared to those obtained by float-point- based wavelet transform (Daubechies) and the JPEG. Peak errors in the reconstructed images by the integer-based wavelet transform are also much lower than those obtained by the JPEG and the float-point-based wavelet coding. In near lossless compression, lossless encoding of the wavelet coefficients of the pre-quantized image shows higher PSNR than those with the bit rate control by the bit plane-band ordering of the wavelet coefficients of the original image without pre-quantization. Using pre-quantization, peak error can also be uniquely controlled, which may be an important feature in medical image compression.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Ten patients with long QT syndromes (LQTs) and torsade de pointes (Tdp) were evaluated. The following features were noticed: (1) Serum potassium concentration was reduced in 5 of 10 patients (50.0%, mean value 3.0 mmol/L); (2) The QT interval (mean value 0.50s) was significantly prolonged in all patients; (3) A flat and wide T wave, an abnormal increase in U wave amplitude close to the end or the peak of the T wave and these changes were accentuated by pause or a sudden deceleration in ventricular rhythm; (4) The critical beat of Tdp inevitably started after the peak of the T wave of a markedly prolonged QT interval. Cycle lengths preceding torsade de pointes were shown in a pattern of short cycle-long QT-"late premature ventricular contraction" initiating sequence changes.

This paper reports on 70 patients with tumors of the trachea, bronchus and lung treated by reconstruction of the trachea, carina and the main bronchus (21 cases) and sleeve lobectomy (49 cases). Postoperatively, 2 patients died of tracheo-innominate artery fistula and 2 developed empyema which was healed. There was no mortality in the sleeve lobectomy patients. The 3- and 5-year survival rates of the cancer patients treated by reconstruction of trachea, carina and main bronchus were 54.5%(6/11) and 33.3%(3/9), respectively. The 3- and 5-year survival rates of lung cancer patients treated by sleeve lobectomy were 46.6% (14/30) and 33.3% (7/21), respectively.