Information on wind-induced damage to civil structures in Argentina is scarce. In this paper, general trends regarding both meteorological conditions and patterns of damage when damage occurred in two regions of Argen...Information on wind-induced damage to civil structures in Argentina is scarce. In this paper, general trends regarding both meteorological conditions and patterns of damage when damage occurred in two regions of Argentina are presented. The regions under study were the north-east of Argentina （NEA） and the north-Patagonia. This research is based on a collection of data comprising field surveys conducted after the passage of destructive storms, NCEP/NCAR Reanalysis, a Global Data Assimilation System model and other secondary sources like emergency services, local press, local councils and the National Weather Service. It is shown that both regions have similar problems of vulnerability, even though they have different meteorological environments. Topics that must be addressed to reduce the vulnerability of civil structures have been identified.展开更多
Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 dis...Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 distribution in tree rings exhibits a well-defined cyclicity. Results obtained from investigations into long-term CO2 and H2O variations in tree discs performed by different methods are presented. Wavelet and spectral analyses of the relationship between CO2 and H2O variations in a Siberian stone pine disc and meteorological parameters were made. The CO2 annual distributions of seven spruce tree discs were examined by the Caterpiller-SSA method. Wood samples of Siberian stone pine and spruce trees were taken from the same site in Tomsk region （Siberia, Russia） that characterized by an optimum growth habitat. Conclusions are made regarding the response of the annual CO2 and H2O conifer disc tree ring distributions to different climatic factors.展开更多
Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green f...Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonist. The following compounds were tested singly and in various combinations: purified Trichoderma P1 enzymes (endochitinase, exochitinase, chitobiosidase, glucanase); antagonist culture filtrates (T. atroviride P1 wild-type and relative knock-out mutants, T. harzianum, T. reesei); pathogen culture filtrates (Botrytis, Pythium, Rhizoctonia); purified fungal cell walls (CWs) from Trichoderma, Botrytis, Pythium, Rhizoctonia; colloidal crab shell chitin; and plant extracts from cucumber leaves, stems or roots. Strong induction of mycoparasitism was found with the various digestion products produced by treating fungal CWs and colloidal chitin with purified enzymes or fungal culture filtrates. Filtrates from chitinase knock-out mutants, as well as CWs from Oomycetes fungi, were less active in producing the stimulus for mycoparasitism. The host CW digestion products were separated by molecular weight (MW) to determine which compounds were able to activate Trichoderma. Micromolecules of MW less than 3 kDa were found to trigger mycoparasitism gene expression before physical contact with the host pathogen. These compounds stimulated mycelial growth and spore germination of the antagonist. Purification of these host-derived compounds was conducted by HPLC and in vivo assay. The obtained inducers were able to stimulate both the production of endochitinase and exochitinase enzymes, even under repressing conditions in the presence of glucose. Inducers stimulated the biocontrol effect of P1 in the presence of host fungi. The disease symptom development on bean leaves inoculated with Botrytis and Trichoderma spores was clearly reduced by the addition of the inducers, unless these molecules were not specifically inactivated. Finally, purified inducers added to liquid cultures of T. atroviride P1 stimulated the production of low MW antibiotics and metabolites which inhibited Botrytis spore germination. Mass spectrometry analysis (ESI-MS) of the inducers indicated the presence of hexose oligomers, like cellobiose, while MS/MS analysis by selective fragmentation of peaks in the spectrum demonstrated the presence of at least three distinct compounds that were biologically active.展开更多
The research area is situated in the western part of Tarim basin,which includes Awati depression and Bachu uplifted block. It underwent three times processes of compression in a large scale and a near term extension s...The research area is situated in the western part of Tarim basin,which includes Awati depression and Bachu uplifted block. It underwent three times processes of compression in a large scale and a near term extension since Cambrian. The first compression occurred during Middle Cambrian to Devonian, which formed fault band folds in NW axial direction. They were "under-water uplift"and distributed all over the research area. The second compression occurred in Late Permian and formed fault band folds and a few fault propagation folds in NS axial direction. They are developed near Tumuxiuke fault belt and the northern research area. The western anticline is bigger than the eastern one in extent and size. The third compression occurred during Palaeogene to Quaternary and formed tumuxiuke fault belt and fault propagation folds in NW direction. They are distributed over the south part of the research area. Tumuxiuke fault belt is a big scale dextral reversed strike-slip fault belt; it transformed or destroyed the fold structure of the research area. A short-term extension occurred during Early Permian. Tarim Basin is in the rift forming stage of craton, and there exist widespread basic volcanic rocks, basic intrusive bodies and dikes.展开更多
In order to analyze the seismic brightness temperature anomalies associated with the Yutian earthquake which occurred at Yutian County, Xinjiang on February 12,2014, daily brightness temperature data was collected fro...In order to analyze the seismic brightness temperature anomalies associated with the Yutian earthquake which occurred at Yutian County, Xinjiang on February 12,2014, daily brightness temperature data was collected from the China Geostationary Meteorological Satellite FY-2E,for the period from May 1,2012 to April 30,2014 and the geographical extent of 30°- 45°N latitude and 70°- 95°E longitude. The continuous wavelet transform method was used to analyze the relative wavelet power spectrum( RWPS) of brightness temperature data for each pixel. And the RWPS time-spatial evolution within the analysis area was obtained. The results showed that the anomaly started to appear at the vicinity of epicentre since October 2013, and anomalous areas gradually enlarged and stretched towards to Altun fault zone and the eastern part of West Kunlun fault zone. Anomalies began to appear at fault zones at Middle Tianshan Mountains, Southern Tianshan Mountains and the western part of the West Kunlun Mountains area which is located at the western margin of Tarim basin,since November 2013. Then anomalous area further enlarged and gathered along fault zones,and eventually,anomalous belts were developed along fault zones around the Tarim basin. The anomaly area and amplitude reached their maximum in late December 2013 and early January 2014. With the impending earthquake,the anomaly area and amplitude dwindled. Anomalies at the vicinity of epicentre disappeared days before the occurrence of the main shock. However, the anomaly at Altun and Middle Tianshan areas still remained. After the main shock,the anomaly attenuated quickly and the whole anomaly disappeared in late February 2014.展开更多
There are many advantages of bended wood, such as good-looking shape, simple process and low cost. The product, however, is easy to get recovery, which is urgent to be dealt with. This paper concludes the features of ...There are many advantages of bended wood, such as good-looking shape, simple process and low cost. The product, however, is easy to get recovery, which is urgent to be dealt with. This paper concludes the features of deformation and recovery of bended wood and wood-based composites and summarizes four treating methods to keep dimensional stability. Compared to bended solid wood, some elementary perspectives on the research of bended wood-based composites are presented. The purpose of this paper is to suggest： 1） to investigate the optimum heating time and temperature that bended wood and wood-based composites need from the formation of deformation to the recovery and to the permanent fixation, according to its changes of dimensional stability such as curvature radius; 2） to measure the composites comprised of wood and adhesives on the changes of stress relaxation, dynamic viscoelasticity and crystallization field; 3） to quantitatively analyze changes of the major components in wood cell wall polymers as well as the composites under heat/steam treatment and untreated conditions. It will be helpful for subsequent research to clarify on the mechanisms of permanent fixation of bended wood and also contribute to that of wood-based composites.展开更多
文摘Information on wind-induced damage to civil structures in Argentina is scarce. In this paper, general trends regarding both meteorological conditions and patterns of damage when damage occurred in two regions of Argentina are presented. The regions under study were the north-east of Argentina （NEA） and the north-Patagonia. This research is based on a collection of data comprising field surveys conducted after the passage of destructive storms, NCEP/NCAR Reanalysis, a Global Data Assimilation System model and other secondary sources like emergency services, local press, local councils and the National Weather Service. It is shown that both regions have similar problems of vulnerability, even though they have different meteorological environments. Topics that must be addressed to reduce the vulnerability of civil structures have been identified.
文摘Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 distribution in tree rings exhibits a well-defined cyclicity. Results obtained from investigations into long-term CO2 and H2O variations in tree discs performed by different methods are presented. Wavelet and spectral analyses of the relationship between CO2 and H2O variations in a Siberian stone pine disc and meteorological parameters were made. The CO2 annual distributions of seven spruce tree discs were examined by the Caterpiller-SSA method. Wood samples of Siberian stone pine and spruce trees were taken from the same site in Tomsk region （Siberia, Russia） that characterized by an optimum growth habitat. Conclusions are made regarding the response of the annual CO2 and H2O conifer disc tree ring distributions to different climatic factors.
文摘Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonist. The following compounds were tested singly and in various combinations: purified Trichoderma P1 enzymes (endochitinase, exochitinase, chitobiosidase, glucanase); antagonist culture filtrates (T. atroviride P1 wild-type and relative knock-out mutants, T. harzianum, T. reesei); pathogen culture filtrates (Botrytis, Pythium, Rhizoctonia); purified fungal cell walls (CWs) from Trichoderma, Botrytis, Pythium, Rhizoctonia; colloidal crab shell chitin; and plant extracts from cucumber leaves, stems or roots. Strong induction of mycoparasitism was found with the various digestion products produced by treating fungal CWs and colloidal chitin with purified enzymes or fungal culture filtrates. Filtrates from chitinase knock-out mutants, as well as CWs from Oomycetes fungi, were less active in producing the stimulus for mycoparasitism. The host CW digestion products were separated by molecular weight (MW) to determine which compounds were able to activate Trichoderma. Micromolecules of MW less than 3 kDa were found to trigger mycoparasitism gene expression before physical contact with the host pathogen. These compounds stimulated mycelial growth and spore germination of the antagonist. Purification of these host-derived compounds was conducted by HPLC and in vivo assay. The obtained inducers were able to stimulate both the production of endochitinase and exochitinase enzymes, even under repressing conditions in the presence of glucose. Inducers stimulated the biocontrol effect of P1 in the presence of host fungi. The disease symptom development on bean leaves inoculated with Botrytis and Trichoderma spores was clearly reduced by the addition of the inducers, unless these molecules were not specifically inactivated. Finally, purified inducers added to liquid cultures of T. atroviride P1 stimulated the production of low MW antibiotics and metabolites which inhibited Botrytis spore germination. Mass spectrometry analysis (ESI-MS) of the inducers indicated the presence of hexose oligomers, like cellobiose, while MS/MS analysis by selective fragmentation of peaks in the spectrum demonstrated the presence of at least three distinct compounds that were biologically active.
文摘The research area is situated in the western part of Tarim basin,which includes Awati depression and Bachu uplifted block. It underwent three times processes of compression in a large scale and a near term extension since Cambrian. The first compression occurred during Middle Cambrian to Devonian, which formed fault band folds in NW axial direction. They were "under-water uplift"and distributed all over the research area. The second compression occurred in Late Permian and formed fault band folds and a few fault propagation folds in NS axial direction. They are developed near Tumuxiuke fault belt and the northern research area. The western anticline is bigger than the eastern one in extent and size. The third compression occurred during Palaeogene to Quaternary and formed tumuxiuke fault belt and fault propagation folds in NW direction. They are distributed over the south part of the research area. Tumuxiuke fault belt is a big scale dextral reversed strike-slip fault belt; it transformed or destroyed the fold structure of the research area. A short-term extension occurred during Early Permian. Tarim Basin is in the rift forming stage of craton, and there exist widespread basic volcanic rocks, basic intrusive bodies and dikes.
基金funded by the National Natural Science Foundation of China(41204057)Seismic Situation Tracking Project of China Earthquake Administration(20150401)
文摘In order to analyze the seismic brightness temperature anomalies associated with the Yutian earthquake which occurred at Yutian County, Xinjiang on February 12,2014, daily brightness temperature data was collected from the China Geostationary Meteorological Satellite FY-2E,for the period from May 1,2012 to April 30,2014 and the geographical extent of 30°- 45°N latitude and 70°- 95°E longitude. The continuous wavelet transform method was used to analyze the relative wavelet power spectrum( RWPS) of brightness temperature data for each pixel. And the RWPS time-spatial evolution within the analysis area was obtained. The results showed that the anomaly started to appear at the vicinity of epicentre since October 2013, and anomalous areas gradually enlarged and stretched towards to Altun fault zone and the eastern part of West Kunlun fault zone. Anomalies began to appear at fault zones at Middle Tianshan Mountains, Southern Tianshan Mountains and the western part of the West Kunlun Mountains area which is located at the western margin of Tarim basin,since November 2013. Then anomalous area further enlarged and gathered along fault zones,and eventually,anomalous belts were developed along fault zones around the Tarim basin. The anomaly area and amplitude reached their maximum in late December 2013 and early January 2014. With the impending earthquake,the anomaly area and amplitude dwindled. Anomalies at the vicinity of epicentre disappeared days before the occurrence of the main shock. However, the anomaly at Altun and Middle Tianshan areas still remained. After the main shock,the anomaly attenuated quickly and the whole anomaly disappeared in late February 2014.
文摘There are many advantages of bended wood, such as good-looking shape, simple process and low cost. The product, however, is easy to get recovery, which is urgent to be dealt with. This paper concludes the features of deformation and recovery of bended wood and wood-based composites and summarizes four treating methods to keep dimensional stability. Compared to bended solid wood, some elementary perspectives on the research of bended wood-based composites are presented. The purpose of this paper is to suggest： 1） to investigate the optimum heating time and temperature that bended wood and wood-based composites need from the formation of deformation to the recovery and to the permanent fixation, according to its changes of dimensional stability such as curvature radius; 2） to measure the composites comprised of wood and adhesives on the changes of stress relaxation, dynamic viscoelasticity and crystallization field; 3） to quantitatively analyze changes of the major components in wood cell wall polymers as well as the composites under heat/steam treatment and untreated conditions. It will be helpful for subsequent research to clarify on the mechanisms of permanent fixation of bended wood and also contribute to that of wood-based composites.
