Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using t...Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using the FLUENT 6.0 software. The simulation results are compared with the experimental data. The effects of the steam to biomass ratio (S/B), the equivalence ratio (ER), and the size of biomass particles on the hydrogen yield were studied. Meanwhile, the distributions of hydrogen inside the gasifier at different conditions are also described.展开更多
Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biod...Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biodegradability and rheological properties were studied. Glycerol and urea, to some extent, can both decrease the tensile strength and increase percentage elongation at break, because the former acts as a plasticizer and the latter can break down interactions among starch macromolecules. Thermoplastic starch shows thermoplasticity and its melt behaves as a pseudoplastic liquid at a low shear rate. Its biodegrading extent is slightly higher than that of native starch. The molecular weight of starch displays a decreasing tendency after thermoplastic modification.展开更多
Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25℃, 70℃ and 100℃ water for 5 min. The structur...Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25℃, 70℃ and 100℃ water for 5 min. The structural changes were observed using a light microscope and the rheological parameters (rupture strength, adhesive strength and deformation) determined using a texture meter. Microscopic photograph revealed that the structural change of heated meat was greater than that of raw meat. The rupture strength, adhesive strength and deformation of raw meat were smaller than those of the heated meat. Meanwhile, rheological parameters showed positive correlation with heating temperature. These changes are mainly caused by thermal denaturation and gelatinization of collagen during heating. These changes were also evidenced in observations using a light microscope and differential scanning calorimetry.展开更多
Silicon is a necessary nutrient for diatoms, silicon uptake in diatom reproduction decreased sea- water silicon content. This paper clarified the characteristics of silicon transferring in the sea, which plays an impo...Silicon is a necessary nutrient for diatoms, silicon uptake in diatom reproduction decreased sea- water silicon content. This paper clarified the characteristics of silicon transferring in the sea, which plays an important role in phytoplankton growth, zooplankton graze and marine ecosystem. Analysis revealed that silicate is supplied by terrestrial sources, through plankton uptake, death, and eventually deposits to the sea bottom, and cannot diffuse upward. This is a general silicon deficit process. Many global marine waters showed the same silicon transfer route: land→silicon biogeochemical process→sea bottom. River flow brings abundant silicate into marine waters, silicate concentration in the waters decreased in the distance away from the river estuaries. In discussion of silicon characteristics and its transfer route, it was considered that the main factor controlling the mechanism of diatom and non-diatom red tides occurrence is silicon, and the changes in silicon source. Human activities, such as sea-route cutting by building embankment and dam, and silicon supplement by the sea, such as sandstorm, rainstorm and storm tide, have largely impaired the earth ecosystem and hugely threatened the human existence. It is suggested in this paper that man should resume the original face of the Si input into the sea to keep natural ecosystem in sustainable pattern.展开更多
Varying-coefficient models are a useful extension of classical linear model. They are widely applied to economics, biomedicine, epidemiology, and so on. There are extensive studies on them in the latest three decade y...Varying-coefficient models are a useful extension of classical linear model. They are widely applied to economics, biomedicine, epidemiology, and so on. There are extensive studies on them in the latest three decade years. In this paper, many of models related to varying-coefficient models are gathered up. All kinds of the estimation procedures and theory of hypothesis test on the varying-coefficients model are summarized. Prom my opinion, some aspects waiting to study are proposed.展开更多
This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range,...This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range, Russia. Fieldwork was conducted in the catchment of Obruchev Glacier(13 km2) during the summer peak flow period in 2008. River discharge was dominated by snowmelt and changed from 3300 l s-1 to less than 1000 l s-1. The mean daily air temperatures of stations situated in the mountain tundra and near Obruchev Glacier from July 11 th to August 1st 2008 were 14.4°C and 10.3°C, respectively. The glacial river had low total dissolved solids varying from 4.5 to 9 mg l-1 and coefficients of correlation between Na+ and Cl-, K+ and Cl-, as well as NH4+ and Cl- were 0.94, 0.90 and 0.84, respectively. Rainfall events affected the snowmelt initiation and provided an essential part of the discharge during the intense snowmelt period, which occurred from July 11 th to July 18 th 2008. Data showed that Na+ and K+ in the surface water derived from snowmelt rather than chemical weathering of silicates. Also, it was obtained that NO3- derived from the melting snowpack, whereas ammonification occurring under the snowpacks was the primary source for NH4+.展开更多
This study was carried out during 2007-2009 in the vineyards of Ardebil province of lran to study the biology and the epidemiology of Uncinula necator--the causal agent of grape powdery mildew disease. The study conce...This study was carried out during 2007-2009 in the vineyards of Ardebil province of lran to study the biology and the epidemiology of Uncinula necator--the causal agent of grape powdery mildew disease. The study concentrated on the survival and the initiation of primary inoculum of the fungal causal agent. Results of histopathological experiments indicated that U. necator survived as mycelium in the dormant buds of the grapes during winter season. Results of study on the effect of environmental factors on fungus biology showed that the pathogenic activity of the fungus began when the temperature was between 16-19 ℃ with a relative humidity more than 50%. It was also found that optimum temperature and relative humidity for the sporulation of U.necator was 20-25 ~C and 50%-100% respectively. According to the results, fungal conidia were trapped during formation of 5-6 true leaves and first disease symptoms were observed on the clusters on late June after fruit formation. Fungal cleistothecia were observed abundantly at the end of season on the leaves, petioles and twigs but they were not able to survive during winter. Formation of ascospores on young leaves was proved but their role as the primary inoculum was not supported by the results of this study. Results of this study and the new findings on the biology and epidemiology of U.necator may be of national and international interests for the management of powdery mildew disease which is one of the most destructive diseases around the world including Iran.展开更多
The comparative analysis of the biological characterization and the genetic background study of EV71 circulating strains is commonly recognized as basic work necessary for development of an effective EV71 vaccine. In ...The comparative analysis of the biological characterization and the genetic background study of EV71 circulating strains is commonly recognized as basic work necessary for development of an effective EV71 vaccine. In this study, we sequenced five EV71 circulating strains, isolated from Fuyang, Hefei, Kunming and Shenzhen city of China and named them FY-23, FY-22, H44, K9 and S1 respectively. The sequence alignment demonstrated their genotypes be C4. The genetic distance of the VP1 gene from these isolates suggested that they were highly co-related with genetic identity similar to other previously reported EV71 strains in China. Additionally, these strains were identified to display some obvious proliferation dynamics and plaque morphology when propagated in Vero cells. However, a distinctive difference in pathogenic ability in neonatal mice was found. Some differences in cross neutralization test & immunogenic analysis were also found. All these results are related to the biological characterization of circulating EV71 strains in China and aid in the development of an EV71 vaccine in the future.展开更多
AIM: To investigate the seroprevalence and molecular characteristics of hepatitis E virus (HEV) in the illegal blood donors (IBDs) of central China in the early 1990s.
Deposition of TiO2 film from atmospheric pressure non- equilibrium Ar/O2/TiCl4 plasma was done to study the effect of discharge power during the film deposition process in this paper. TiO2 films with kinds of morpholo...Deposition of TiO2 film from atmospheric pressure non- equilibrium Ar/O2/TiCl4 plasma was done to study the effect of discharge power during the film deposition process in this paper. TiO2 films with kinds of morphologies and controlled crystallization were deposited from mixtures of TiCl4 and O2 on quartz substrate by one step process. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to analyze the morphology and crystallization of the deposited TiO2 films. It was found that the discharge power played a key role in the morphology and crystallization of the deposited TiO2 film whether the flow of TiCl4was large or small. When the flow of TiCl4 was large, the deposited TiO2 film was amorphous particles at low discharge power and was multi-crystalline at high discharge power. When the flow of TiCl4 was small, the deposited TiO2 film became more compact and the crystallization was enhanced as the discharge power increased. The dependence of the discharge current and the applied voltage with the discharge power indicated that it was a glow discharge. The gas temperature which increases with the discharge power is one of the main causes that affect the morphology and crystallization of the deposited film.展开更多
Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This mini...Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This minireview presents an expatiation of history perspectives and research developments upon basic concepts including hybrid zones, hybridization, hybrid and its the genetic cline model. Moreover, by figuring out the existing problem around the hybrids within conservative theory and practices, it suggests that the theory of hybrid zone be introduced into conservation biology and it would be provide a broader and more open theoretical background for conservative research and practices.展开更多
Coated wire sensor for potentiometric determination ofDAP (dapoxetine HCI) in pure form and in biological fluidsbased on DAP-TPB (dapoxetine-tetraphenyl borate) as the sensing element in the presence of DOP (dioc...Coated wire sensor for potentiometric determination ofDAP (dapoxetine HCI) in pure form and in biological fluidsbased on DAP-TPB (dapoxetine-tetraphenyl borate) as the sensing element in the presence of DOP (dioctylphthalate) as the plasticizing solvent mediator was prepared. The best performance was obtained with a membrane composition of 10.0% (w/w) ion-pair, 45.0% DOP (w/w) and 45.0% PVC (w/w). The electrode showed a Nemstian response (with a slope of 58.70 mV decade-1) for the concentration range of 4.2 × 10-5-1.0 ×10-2 mol/L. It illustrates a relatively fast response time in the whole concentration range (-15 s) in a pH range of 3.0-7.5. The selectivity coefficients were determined in relation to several inorganic and organic species. DAP is determined successfully in pure solutions and in biological fuids using the standard additions and petentiometric titrations methods.展开更多
All known subtypes of influenza A viruses are maintained in wild waterfowl, the natural reservoir of these viruses. Influenza A viruses are isolated from a variety of animal species with varying morbidity and mortalit...All known subtypes of influenza A viruses are maintained in wild waterfowl, the natural reservoir of these viruses. Influenza A viruses are isolated from a variety of animal species with varying morbidity and mortality rates. More importantly, influenza A viruses cause respiratory disease in humans with potentially fatal outcome. Local or global outbreaks in humans are typically characterized by excess hospitalizations and deaths. In 1997, highly pathogenic avian influenza viruses of the H5N1 subtype emerged in Hong Kong that transmitted to humans, resulting in the first documented cases of human death by avian influenza virus infection. A new outbreak started in July 2003 in poultry in Vietnam, Indonesia, and Thailand, and highly pathogenic avian H5N1 influenza viruses have since spread throughout Asia and into Europe and Africa. These viruses continue to infect humans with a high mortality rate and cause worldwide concern of a looming pandemic. Moreover, H5N1 virus outbreaks have had devastating effects on the poultry industries throughout Asia. Since H5N1 virus outbreaks appear to originate from Southern China, we here examine H5N1 influenza viruses in China, with an emphasis on their biological properties.展开更多
To optimize the design and improve the performance of wastewater treatment bioreactors,the review concerning the hydrodynamics explored by theoretical equations,process experiments,modeling of the hydrodynamics and fl...To optimize the design and improve the performance of wastewater treatment bioreactors,the review concerning the hydrodynamics explored by theoretical equations,process experiments,modeling of the hydrodynamics and flow field measurement is presented. Results of different kinds of experiments show that the hydrodynamic characteristics can affect sludge characteristics,mass transfer and reactor performance significantly. Along with the development of theoretical equations,turbulence models including large eddy simulation models and Reynolds-averaged Navier-Stokes (RANS) models are widely used at present. Standard and modified k-ε models are the most widely used eddy viscosity turbulence models for simulating flows in bioreactors. Numerical simulation of hydrodynamics is proved to be efficient for optimizing design and operation. The development of measurement techniques with high accuracy and low intrusion enables the flow filed in the bioreactors to be transparent. Integration of both numerical simulation and experimental measurement can describe the hydrodynamics very well.展开更多
Objective:To assess the influe nce of mimic cardiac rate on hydrodynamics of the different mechanical prostheti c cardiac valves.Methods:US-made CarboMedics bile aflet valve and China-made Jiuling bileafle t valve and...Objective:To assess the influe nce of mimic cardiac rate on hydrodynamics of the different mechanical prostheti c cardiac valves.Methods:US-made CarboMedics bile aflet valve and China-made Jiuling bileafle t valve and C-L tilting disc valve have been tested in a pulsatile flow simulat or in the aortic position. The testing condition was set at the mimic cardiac r ate of 55 beats/min,75 beats/min,100beats/min and a constant mimic cardiac out put of 4L/min. The mean pressure differences(ΔP),leakage volumes (LEV) and closi ng volumes(CLV) across each valve,and the effective orifice areas(EOA) have bee n analyzed.Results:Within the range of physiology, the ΔP,LEV and CLV were falling as the increasing of mimic cardiac rate,and the extent of variance was larger. The EOA was increasing with the increase of the mimic cardiac rate. It is a differe nt response as the altering of the cardiac rate for the different type of the me chanical prosthetic cardiac valves.Conclusions:The change of the mimic cardiac rate can affect the hydrodynamics of the mechanical prosthetic cardiac valves. The hydrodynamics of the bileaflet valve prosthesis is better than the tilting disc valve.展开更多
OBJECTIVE To observe the effects expression and activation on biological cancer stem cells. of blocking CD133 gene characteristic of the colon METHODS CD133+ colon cancer stem cells (CCSCs) were separated from EpCA...OBJECTIVE To observe the effects expression and activation on biological cancer stem cells. of blocking CD133 gene characteristic of the colon METHODS CD133+ colon cancer stem cells (CCSCs) were separated from EpCAMhigh CD44+ CCSCs through fluorescenceactivated cell sorting (FACS). The proliferation, the capability of spherical cell formation, neoplasia, and the expression of ABCG2 mRNA of CD133+ CCSCs were observed after the CD133+ CCSCs were infected with LV-CD133shRNA. CD133 negative cells were isolated from EpCAMhigh CD44+ CCSCs with FACS, and the CD133 proteins in CD133- cells were detected with Western blot. RESULTS CD133+ CCSCs were isolated from EpCAMhigh CD44+ CCSCs using FACS, and they accounted for 89.2% in the stem cells. In the experimental group, after the CD133+ CCSCs were knocked down by LV-CD133shRNA RNAi, the growth pattern of the cells in the stem cell culture changed into adherent growth from suspended growth, and couldn't generate spherical cells. Results of MTT assay showed that the CD133+ CCSCs infected with LV-CD133shRNA grew slowly, compared to the cells in the control groups. There was a decrease in the cloning efficiency. The infected cells were transplanted into the BALB/c nude mice. During the observation, no neoplasia was found in the CD133+ cells infected with LV-CD133shRNA. The level of ABCG2 mRNA expression was lowered greatly (P 〈 0.01). CD133- cells were obtained from the EpCAMhigh CD44+ CCSCs using FACS, in which the expression of CD133 protein was positive. CONCLUSION CD133 retains the biological characteristics of the colon cancer stem cells.展开更多
The developing world still largely depends on biomass, such as wood, animal dung and agricultural waste for domestic fuel sources that are typically burned in traditional stoves. Ethiopia has different biomass resourc...The developing world still largely depends on biomass, such as wood, animal dung and agricultural waste for domestic fuel sources that are typically burned in traditional stoves. Ethiopia has different biomass resource for biochar production, through pyrolysis cook stove co-producing biochar. Coffee husks are the major solid residues from the handling and processing of coffee in the study area. This study was to evaluate the biochar co-producing pyrolysis cook stove with respect to heat transfer through the bed and biochar yield. From allothermal type of pyrolysis cook stove, the stove design was selected for both the computational fluid dynamic (CFD) simulation and experimental measurements. ANSYS 14.5 was used for CFD simulation of the wood combustion. The production of biochar from coffee husk, corncob and sawdust at different heating times, bed and stove surface temperature were undertaken. Bulk density, pH and surface area of the biochar were measured. While good agreement between simulation and experimental result was obtained in the conduction phase during pyrolysis, deviation between the two on account of the effect of volatile gas in changing the temperature trend within the biomass bed was noticed. Within the biomass type, the maximum mean biochar yield (38.91%) was seen from coffee husk. In the case of different stove designs, the minimum mean biochar yield (27.11%) was found from normal Anila stove. The pH of biochar is found to be significantly affected by the type of biomass (9.83 mean for corncob and coffee husk, 6.43 mean for sawdust), heating time (9.19 mean for 90 min and 8.01 mean for 30 min) and stove type (9.52 mean for normal Anila and 8.01 mean for flangeless Anila continuous feeding type). In fact, the type of biomass is observed to significantly affect the bulk density and surface area ofbiochar.展开更多
Biomass plants often struggle to capture flow measurements reliably. High amounts of dry solids and fats complicate the measurement with an MID (Magnetic-Inductive) flowmeter and make it susceptible to faults. To ov...Biomass plants often struggle to capture flow measurements reliably. High amounts of dry solids and fats complicate the measurement with an MID (Magnetic-Inductive) flowmeter and make it susceptible to faults. To overcome this impediment, the waste water treatment plant in Innsbruck, Austria, relies on electromagnetic pulsed AC (Alternating Current) flowmeters. Compared to pulsed DC (Direct Current) devices, AC devices are able to build up magnetic fields that are ten times stronger. Equipped with this capability, the Sitrans Transmag 2 is able to guarantee a constant and also high measuring accuracy, zero point stability and signal strength regardless of impurities in the medium or fluctuations in the magnetic field.展开更多
The purposes of this study are to compare the proteome of Vibrio cholerae O139 strains with that of O22, O155 and El Tot biotype epidemic strains, and to identifv whether O139 strains have a close relation with the la...The purposes of this study are to compare the proteome of Vibrio cholerae O139 strains with that of O22, O155 and El Tot biotype epidemic strains, and to identifv whether O139 strains have a close relation with the latter. Proteins of two V. cholerae serogroup O139 strains, two El Tor biotype epidemic strains, one O22 strain, and one O155 strain were separated by two-dimensional gel electrophoresis (2-DE) ; the silver stained 2-DE gels were scanned with (ligital lmageScanner and analyzed with lmageMaster 2D Elite 3.10 software. Similarities of protein maps between these strains were analyzed. The two O139 strains had 86% proteins in common; the two El Tor biotype epidemie strains showed 84% proteins in common; O139 strains shared 67 % , 47 % and 45 % proteins with El Tor biotype epidemic strains, O22 and O 155 strains respectively. Although the proteome of O 139 strains have close similarity to that of El Tor biotype epidemic strains, great disparities exist. O139 strains may not originate from El Tor biotype directly, and a transition strain may exist.展开更多
文摘Fluidized bed biomass gasifiers can be employed to produce hydrogen-rich gas. A non-premixed combustion model is used for biomass air-steam gasification in the gasifier, and the simulations were carried out by using the FLUENT 6.0 software. The simulation results are compared with the experimental data. The effects of the steam to biomass ratio (S/B), the equivalence ratio (ER), and the size of biomass particles on the hydrogen yield were studied. Meanwhile, the distributions of hydrogen inside the gasifier at different conditions are also described.
文摘Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biodegradability and rheological properties were studied. Glycerol and urea, to some extent, can both decrease the tensile strength and increase percentage elongation at break, because the former acts as a plasticizer and the latter can break down interactions among starch macromolecules. Thermoplastic starch shows thermoplasticity and its melt behaves as a pseudoplastic liquid at a low shear rate. Its biodegrading extent is slightly higher than that of native starch. The molecular weight of starch displays a decreasing tendency after thermoplastic modification.
基金supported by the proiect sponsored by the Scientific Research Foundation for Returned Overseas Chinese Scholars,State Education Ministry(SRF for ROCS,SEM)the Natural Science Foundation of Shandong(No.2004BSO7003)and Qingdao(No.04-2-JZ-110)
文摘Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25℃, 70℃ and 100℃ water for 5 min. The structural changes were observed using a light microscope and the rheological parameters (rupture strength, adhesive strength and deformation) determined using a texture meter. Microscopic photograph revealed that the structural change of heated meat was greater than that of raw meat. The rupture strength, adhesive strength and deformation of raw meat were smaller than those of the heated meat. Meanwhile, rheological parameters showed positive correlation with heating temperature. These changes are mainly caused by thermal denaturation and gelatinization of collagen during heating. These changes were also evidenced in observations using a light microscope and differential scanning calorimetry.
基金This study was funded by the key subject development of Shanghai Education Council (04SC12), the Director’s Foundation of the Beihai Monitoring Center and the State Oceanic Administration and Chinese Academy of Science (KZCX 2-207).
文摘Silicon is a necessary nutrient for diatoms, silicon uptake in diatom reproduction decreased sea- water silicon content. This paper clarified the characteristics of silicon transferring in the sea, which plays an important role in phytoplankton growth, zooplankton graze and marine ecosystem. Analysis revealed that silicate is supplied by terrestrial sources, through plankton uptake, death, and eventually deposits to the sea bottom, and cannot diffuse upward. This is a general silicon deficit process. Many global marine waters showed the same silicon transfer route: land→silicon biogeochemical process→sea bottom. River flow brings abundant silicate into marine waters, silicate concentration in the waters decreased in the distance away from the river estuaries. In discussion of silicon characteristics and its transfer route, it was considered that the main factor controlling the mechanism of diatom and non-diatom red tides occurrence is silicon, and the changes in silicon source. Human activities, such as sea-route cutting by building embankment and dam, and silicon supplement by the sea, such as sandstorm, rainstorm and storm tide, have largely impaired the earth ecosystem and hugely threatened the human existence. It is suggested in this paper that man should resume the original face of the Si input into the sea to keep natural ecosystem in sustainable pattern.
基金Foundation item: Supported by the National Natural Science Foundation of China(10501053) Acknowledgement I would like to thank Henan Society of Applied Statistics for which give me a chance to declare my opinion about the varying-coefficient model.
文摘Varying-coefficient models are a useful extension of classical linear model. They are widely applied to economics, biomedicine, epidemiology, and so on. There are extensive studies on them in the latest three decade years. In this paper, many of models related to varying-coefficient models are gathered up. All kinds of the estimation procedures and theory of hypothesis test on the varying-coefficients model are summarized. Prom my opinion, some aspects waiting to study are proposed.
基金supported by the Institute of Geography and Spatial Management at Jagiellonian University
文摘This study aims to determine the relationships between local meteorological conditions,proglacial river discharge and biogeochemical processes operating in a periglacial basin located in the Polar Ural mountain range, Russia. Fieldwork was conducted in the catchment of Obruchev Glacier(13 km2) during the summer peak flow period in 2008. River discharge was dominated by snowmelt and changed from 3300 l s-1 to less than 1000 l s-1. The mean daily air temperatures of stations situated in the mountain tundra and near Obruchev Glacier from July 11 th to August 1st 2008 were 14.4°C and 10.3°C, respectively. The glacial river had low total dissolved solids varying from 4.5 to 9 mg l-1 and coefficients of correlation between Na+ and Cl-, K+ and Cl-, as well as NH4+ and Cl- were 0.94, 0.90 and 0.84, respectively. Rainfall events affected the snowmelt initiation and provided an essential part of the discharge during the intense snowmelt period, which occurred from July 11 th to July 18 th 2008. Data showed that Na+ and K+ in the surface water derived from snowmelt rather than chemical weathering of silicates. Also, it was obtained that NO3- derived from the melting snowpack, whereas ammonification occurring under the snowpacks was the primary source for NH4+.
文摘This study was carried out during 2007-2009 in the vineyards of Ardebil province of lran to study the biology and the epidemiology of Uncinula necator--the causal agent of grape powdery mildew disease. The study concentrated on the survival and the initiation of primary inoculum of the fungal causal agent. Results of histopathological experiments indicated that U. necator survived as mycelium in the dormant buds of the grapes during winter season. Results of study on the effect of environmental factors on fungus biology showed that the pathogenic activity of the fungus began when the temperature was between 16-19 ℃ with a relative humidity more than 50%. It was also found that optimum temperature and relative humidity for the sporulation of U.necator was 20-25 ~C and 50%-100% respectively. According to the results, fungal conidia were trapped during formation of 5-6 true leaves and first disease symptoms were observed on the clusters on late June after fruit formation. Fungal cleistothecia were observed abundantly at the end of season on the leaves, petioles and twigs but they were not able to survive during winter. Formation of ascospores on young leaves was proved but their role as the primary inoculum was not supported by the results of this study. Results of this study and the new findings on the biology and epidemiology of U.necator may be of national and international interests for the management of powdery mildew disease which is one of the most destructive diseases around the world including Iran.
基金National Science and Technology Major Project (2008ZX10004-014)
文摘The comparative analysis of the biological characterization and the genetic background study of EV71 circulating strains is commonly recognized as basic work necessary for development of an effective EV71 vaccine. In this study, we sequenced five EV71 circulating strains, isolated from Fuyang, Hefei, Kunming and Shenzhen city of China and named them FY-23, FY-22, H44, K9 and S1 respectively. The sequence alignment demonstrated their genotypes be C4. The genetic distance of the VP1 gene from these isolates suggested that they were highly co-related with genetic identity similar to other previously reported EV71 strains in China. Additionally, these strains were identified to display some obvious proliferation dynamics and plaque morphology when propagated in Vero cells. However, a distinctive difference in pathogenic ability in neonatal mice was found. Some differences in cross neutralization test & immunogenic analysis were also found. All these results are related to the biological characterization of circulating EV71 strains in China and aid in the development of an EV71 vaccine in the future.
基金Supported by The Natural Science Foundation of Maanshan,China (2008-40) (To Zhan SW and Zheng JX)
文摘AIM: To investigate the seroprevalence and molecular characteristics of hepatitis E virus (HEV) in the illegal blood donors (IBDs) of central China in the early 1990s.
基金National Natural Science Foundations of China (No.10835004,No.10775031)Science and Technology Commission of Shanghai Municipality,China (No.10XD1400100)
文摘Deposition of TiO2 film from atmospheric pressure non- equilibrium Ar/O2/TiCl4 plasma was done to study the effect of discharge power during the film deposition process in this paper. TiO2 films with kinds of morphologies and controlled crystallization were deposited from mixtures of TiCl4 and O2 on quartz substrate by one step process. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to analyze the morphology and crystallization of the deposited TiO2 films. It was found that the discharge power played a key role in the morphology and crystallization of the deposited TiO2 film whether the flow of TiCl4was large or small. When the flow of TiCl4 was large, the deposited TiO2 film was amorphous particles at low discharge power and was multi-crystalline at high discharge power. When the flow of TiCl4 was small, the deposited TiO2 film became more compact and the crystallization was enhanced as the discharge power increased. The dependence of the discharge current and the applied voltage with the discharge power indicated that it was a glow discharge. The gas temperature which increases with the discharge power is one of the main causes that affect the morphology and crystallization of the deposited film.
文摘Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This minireview presents an expatiation of history perspectives and research developments upon basic concepts including hybrid zones, hybridization, hybrid and its the genetic cline model. Moreover, by figuring out the existing problem around the hybrids within conservative theory and practices, it suggests that the theory of hybrid zone be introduced into conservation biology and it would be provide a broader and more open theoretical background for conservative research and practices.
文摘Coated wire sensor for potentiometric determination ofDAP (dapoxetine HCI) in pure form and in biological fluidsbased on DAP-TPB (dapoxetine-tetraphenyl borate) as the sensing element in the presence of DOP (dioctylphthalate) as the plasticizing solvent mediator was prepared. The best performance was obtained with a membrane composition of 10.0% (w/w) ion-pair, 45.0% DOP (w/w) and 45.0% PVC (w/w). The electrode showed a Nemstian response (with a slope of 58.70 mV decade-1) for the concentration range of 4.2 × 10-5-1.0 ×10-2 mol/L. It illustrates a relatively fast response time in the whole concentration range (-15 s) in a pH range of 3.0-7.5. The selectivity coefficients were determined in relation to several inorganic and organic species. DAP is determined successfully in pure solutions and in biological fuids using the standard additions and petentiometric titrations methods.
基金Acknowledgments We thank Susan Watson for editing the manuscript and those in our laboratories who contributed to the data cited in this review. We also thank Ryo Takano for the preparation of figures. Research in HC's group is supported by the Ministry of Science and Technology, China (2004BA519A-57, 2006BAD06A05). Research in GFG's group is supported by the Ministry of Science and Technology, China (MOST, 2005CB523001 and 2006BAD06A01), the National Natural Science Foundation of China (NSFC, Grant #3059934, #30525010) and the US National Institutes of Health (U19 AI051915-05S1). Research in YS's group is supported by the Ministry of Science and Technology, China (MOST, 2005CB523006 and 2006BAD06A15), and the National Natural Science Foundation of China (NSFC, Grant #30599433). Research in YK's group is supported by National Institute of Allergy and Infectious Diseases Public Health Service research grants by CREST and ERATO (Japan Science and Technology Agency), and by grants-in-aid and a contract research fund for the Program of Founding Research Centers for Emerging and Reemerging Infectious Diseases from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.
文摘All known subtypes of influenza A viruses are maintained in wild waterfowl, the natural reservoir of these viruses. Influenza A viruses are isolated from a variety of animal species with varying morbidity and mortality rates. More importantly, influenza A viruses cause respiratory disease in humans with potentially fatal outcome. Local or global outbreaks in humans are typically characterized by excess hospitalizations and deaths. In 1997, highly pathogenic avian influenza viruses of the H5N1 subtype emerged in Hong Kong that transmitted to humans, resulting in the first documented cases of human death by avian influenza virus infection. A new outbreak started in July 2003 in poultry in Vietnam, Indonesia, and Thailand, and highly pathogenic avian H5N1 influenza viruses have since spread throughout Asia and into Europe and Africa. These viruses continue to infect humans with a high mortality rate and cause worldwide concern of a looming pandemic. Moreover, H5N1 virus outbreaks have had devastating effects on the poultry industries throughout Asia. Since H5N1 virus outbreaks appear to originate from Southern China, we here examine H5N1 influenza viruses in China, with an emphasis on their biological properties.
基金Sponsored by the National Basic Research Program of China( 973 Program)(Grant No.G2000026402)
文摘To optimize the design and improve the performance of wastewater treatment bioreactors,the review concerning the hydrodynamics explored by theoretical equations,process experiments,modeling of the hydrodynamics and flow field measurement is presented. Results of different kinds of experiments show that the hydrodynamic characteristics can affect sludge characteristics,mass transfer and reactor performance significantly. Along with the development of theoretical equations,turbulence models including large eddy simulation models and Reynolds-averaged Navier-Stokes (RANS) models are widely used at present. Standard and modified k-ε models are the most widely used eddy viscosity turbulence models for simulating flows in bioreactors. Numerical simulation of hydrodynamics is proved to be efficient for optimizing design and operation. The development of measurement techniques with high accuracy and low intrusion enables the flow filed in the bioreactors to be transparent. Integration of both numerical simulation and experimental measurement can describe the hydrodynamics very well.
文摘Objective:To assess the influe nce of mimic cardiac rate on hydrodynamics of the different mechanical prostheti c cardiac valves.Methods:US-made CarboMedics bile aflet valve and China-made Jiuling bileafle t valve and C-L tilting disc valve have been tested in a pulsatile flow simulat or in the aortic position. The testing condition was set at the mimic cardiac r ate of 55 beats/min,75 beats/min,100beats/min and a constant mimic cardiac out put of 4L/min. The mean pressure differences(ΔP),leakage volumes (LEV) and closi ng volumes(CLV) across each valve,and the effective orifice areas(EOA) have bee n analyzed.Results:Within the range of physiology, the ΔP,LEV and CLV were falling as the increasing of mimic cardiac rate,and the extent of variance was larger. The EOA was increasing with the increase of the mimic cardiac rate. It is a differe nt response as the altering of the cardiac rate for the different type of the me chanical prosthetic cardiac valves.Conclusions:The change of the mimic cardiac rate can affect the hydrodynamics of the mechanical prosthetic cardiac valves. The hydrodynamics of the bileaflet valve prosthesis is better than the tilting disc valve.
基金The work was supported by a grant from the National Natural Science Foundation of China (No.30970843)
文摘OBJECTIVE To observe the effects expression and activation on biological cancer stem cells. of blocking CD133 gene characteristic of the colon METHODS CD133+ colon cancer stem cells (CCSCs) were separated from EpCAMhigh CD44+ CCSCs through fluorescenceactivated cell sorting (FACS). The proliferation, the capability of spherical cell formation, neoplasia, and the expression of ABCG2 mRNA of CD133+ CCSCs were observed after the CD133+ CCSCs were infected with LV-CD133shRNA. CD133 negative cells were isolated from EpCAMhigh CD44+ CCSCs with FACS, and the CD133 proteins in CD133- cells were detected with Western blot. RESULTS CD133+ CCSCs were isolated from EpCAMhigh CD44+ CCSCs using FACS, and they accounted for 89.2% in the stem cells. In the experimental group, after the CD133+ CCSCs were knocked down by LV-CD133shRNA RNAi, the growth pattern of the cells in the stem cell culture changed into adherent growth from suspended growth, and couldn't generate spherical cells. Results of MTT assay showed that the CD133+ CCSCs infected with LV-CD133shRNA grew slowly, compared to the cells in the control groups. There was a decrease in the cloning efficiency. The infected cells were transplanted into the BALB/c nude mice. During the observation, no neoplasia was found in the CD133+ cells infected with LV-CD133shRNA. The level of ABCG2 mRNA expression was lowered greatly (P 〈 0.01). CD133- cells were obtained from the EpCAMhigh CD44+ CCSCs using FACS, in which the expression of CD133 protein was positive. CONCLUSION CD133 retains the biological characteristics of the colon cancer stem cells.
文摘The developing world still largely depends on biomass, such as wood, animal dung and agricultural waste for domestic fuel sources that are typically burned in traditional stoves. Ethiopia has different biomass resource for biochar production, through pyrolysis cook stove co-producing biochar. Coffee husks are the major solid residues from the handling and processing of coffee in the study area. This study was to evaluate the biochar co-producing pyrolysis cook stove with respect to heat transfer through the bed and biochar yield. From allothermal type of pyrolysis cook stove, the stove design was selected for both the computational fluid dynamic (CFD) simulation and experimental measurements. ANSYS 14.5 was used for CFD simulation of the wood combustion. The production of biochar from coffee husk, corncob and sawdust at different heating times, bed and stove surface temperature were undertaken. Bulk density, pH and surface area of the biochar were measured. While good agreement between simulation and experimental result was obtained in the conduction phase during pyrolysis, deviation between the two on account of the effect of volatile gas in changing the temperature trend within the biomass bed was noticed. Within the biomass type, the maximum mean biochar yield (38.91%) was seen from coffee husk. In the case of different stove designs, the minimum mean biochar yield (27.11%) was found from normal Anila stove. The pH of biochar is found to be significantly affected by the type of biomass (9.83 mean for corncob and coffee husk, 6.43 mean for sawdust), heating time (9.19 mean for 90 min and 8.01 mean for 30 min) and stove type (9.52 mean for normal Anila and 8.01 mean for flangeless Anila continuous feeding type). In fact, the type of biomass is observed to significantly affect the bulk density and surface area ofbiochar.
文摘Biomass plants often struggle to capture flow measurements reliably. High amounts of dry solids and fats complicate the measurement with an MID (Magnetic-Inductive) flowmeter and make it susceptible to faults. To overcome this impediment, the waste water treatment plant in Innsbruck, Austria, relies on electromagnetic pulsed AC (Alternating Current) flowmeters. Compared to pulsed DC (Direct Current) devices, AC devices are able to build up magnetic fields that are ten times stronger. Equipped with this capability, the Sitrans Transmag 2 is able to guarantee a constant and also high measuring accuracy, zero point stability and signal strength regardless of impurities in the medium or fluctuations in the magnetic field.
文摘The purposes of this study are to compare the proteome of Vibrio cholerae O139 strains with that of O22, O155 and El Tot biotype epidemic strains, and to identifv whether O139 strains have a close relation with the latter. Proteins of two V. cholerae serogroup O139 strains, two El Tor biotype epidemic strains, one O22 strain, and one O155 strain were separated by two-dimensional gel electrophoresis (2-DE) ; the silver stained 2-DE gels were scanned with (ligital lmageScanner and analyzed with lmageMaster 2D Elite 3.10 software. Similarities of protein maps between these strains were analyzed. The two O139 strains had 86% proteins in common; the two El Tor biotype epidemie strains showed 84% proteins in common; O139 strains shared 67 % , 47 % and 45 % proteins with El Tor biotype epidemic strains, O22 and O 155 strains respectively. Although the proteome of O 139 strains have close similarity to that of El Tor biotype epidemic strains, great disparities exist. O139 strains may not originate from El Tor biotype directly, and a transition strain may exist.