In caves and monuments, biocorrosion caused by bats occurs partly under accumulations of guano. Tests were carried out both at cave temperature and under hot conditions in the laboratory on 4 different limestones. A c...In caves and monuments, biocorrosion caused by bats occurs partly under accumulations of guano. Tests were carried out both at cave temperature and under hot conditions in the laboratory on 4 different limestones. A comparison of the results obtained using these two methods shows that the processes leading to the weathering of the limestones are the same, and that the hot laboratory tests accelerate them in a well-constrained way. The higher the porosity and capillarity of the limestone, the faster the weathering process. The presence of large calcite crystals also favors weathering. In caves, the ablation rates obtained (8 mm/ka) are sufficient to destroy engravings in a few decades. In monuments, ablation rates are even higher because of the temperature, and could theoretically reach 32 cm/ka in extreme conditions at 80˚C. The laboratory test developed here can be adapted to the temperature of each case study. It has already demonstrated the mechanisms that lead from weathering to the formation of a phosphate crust.展开更多
We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbia...We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism(PAO) and denitrifying PAO(DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days(DPAO SBR)and 250 days(PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%,whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge(3.3%) and DPAO sludge(3.2%), confirming that this organism can use both O_2 and NO_3^- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.展开更多
Objective:To investigate the hepatoprotective potential of Solonum xanthocarpum（Solanaceae） （S.xanthocarpum） in experimental rats to validate its traditional claim.Methods:50%ethanolic fruit extract of S.xanthocar...Objective:To investigate the hepatoprotective potential of Solonum xanthocarpum（Solanaceae） （S.xanthocarpum） in experimental rats to validate its traditional claim.Methods:50%ethanolic fruit extract of S.xanthocarpum（SXE,100.200 or 400 mg/kg hods weight） was administered daily for 14davs in experimental animals.Liver injury was induced chemically,by CCl<sub>4</sub> administration （1 mL/kg i.p.）.The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase（AST）,alanine aminotransferase（ALT）.Serum alkaline phosphatise （SALP） and total bilirubin.Meanwhile,in vivo antioxidant activities as lipid peroxidation（LPO）, reduced glutathione（GSH）.superoxide dismutase（SOD） and calalase（CAT） were screened along with histopathological studies.Results:Obtained results demonstrated that the treatment with SXE significantly（P【0.05- 【0.001） and dose-dcpendcntly prevented chemically induced increase in serum levels of hepatic enzymes.Furthermore.SXE significantly（up to P【0.001） reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH,SOU and catalasc towards normal levels.Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. Conclusions:The results of this study strongly indicate the protective effect of SXE against acute liver injun which may he attributed to its hepatoprotective activity,and there by scientifically support its traditional use.展开更多
The term vertebrate is generally viewed by systematists in two contexts,either as Craniata(myxinoids or hagfishes+vertebrates s.s.,i.e.basically,animals possessing a stiff backbone)or as Vertebrata(lampreys+other vert...The term vertebrate is generally viewed by systematists in two contexts,either as Craniata(myxinoids or hagfishes+vertebrates s.s.,i.e.basically,animals possessing a stiff backbone)or as Vertebrata(lampreys+other vertebrae-bearing animals,which we propose to call here Euvertebrata).Craniates are characterized by a skull;vertebrates by vertebrae(arcualia);euvertebrates are vertebrates with hard phosphatised tissues in the skeleton.The earliest known possible craniate is Myllokunmingia(syn.Haikouichthys)from the Lower Cambrian of Chengjiang,south China.Euvertebrates appear in the Ordovician.C.H.Pander is sometimes thought to have been the first to propose that conodonts are vertebrates,but he did have doubts about the fish affinities of conodonts.This proposal was revived in the 30s and especially in the 80s of the 20th century and given elevated status in 2000 through a cladistic analysis based upon interpretation of conodont mineralized tissues as homologous to those of vertebrates.This analysis resolved conodonts within the clade Vertebrata s.s.,and incorporated a‘Total Group Concept’(TGC),including conodonts in the TG Gnathostomes(=jawed vertebrates).This resulted in the unusual scenario in which“teeth”appear before jaws.We reject the TGC nomenclature as applied to early vertebrates.In addition,based on all existing evidence,we consider that conodont hard tissues and several other anatomical structures in conodonts are not homologous with those of vertebrates.Making a revised cladistic analysis,eliminating characters unknown in fossils,conodonts appear stemward(i.e.more basal)to craniates and are thus interpreted as basal chordates at best.To help resolve the phylogenetic relationships of conodonts and chordates,the analysis should be extended to include non-chordate taxa.展开更多
文摘In caves and monuments, biocorrosion caused by bats occurs partly under accumulations of guano. Tests were carried out both at cave temperature and under hot conditions in the laboratory on 4 different limestones. A comparison of the results obtained using these two methods shows that the processes leading to the weathering of the limestones are the same, and that the hot laboratory tests accelerate them in a well-constrained way. The higher the porosity and capillarity of the limestone, the faster the weathering process. The presence of large calcite crystals also favors weathering. In caves, the ablation rates obtained (8 mm/ka) are sufficient to destroy engravings in a few decades. In monuments, ablation rates are even higher because of the temperature, and could theoretically reach 32 cm/ka in extreme conditions at 80˚C. The laboratory test developed here can be adapted to the temperature of each case study. It has already demonstrated the mechanisms that lead from weathering to the formation of a phosphate crust.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (No.NRF-2015R1D1A1A01061423)
文摘We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism(PAO) and denitrifying PAO(DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days(DPAO SBR)and 250 days(PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%,whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge(3.3%) and DPAO sludge(3.2%), confirming that this organism can use both O_2 and NO_3^- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.
文摘Objective:To investigate the hepatoprotective potential of Solonum xanthocarpum（Solanaceae） （S.xanthocarpum） in experimental rats to validate its traditional claim.Methods:50%ethanolic fruit extract of S.xanthocarpum（SXE,100.200 or 400 mg/kg hods weight） was administered daily for 14davs in experimental animals.Liver injury was induced chemically,by CCl<sub>4</sub> administration （1 mL/kg i.p.）.The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase（AST）,alanine aminotransferase（ALT）.Serum alkaline phosphatise （SALP） and total bilirubin.Meanwhile,in vivo antioxidant activities as lipid peroxidation（LPO）, reduced glutathione（GSH）.superoxide dismutase（SOD） and calalase（CAT） were screened along with histopathological studies.Results:Obtained results demonstrated that the treatment with SXE significantly（P【0.05- 【0.001） and dose-dcpendcntly prevented chemically induced increase in serum levels of hepatic enzymes.Furthermore.SXE significantly（up to P【0.001） reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH,SOU and catalasc towards normal levels.Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. Conclusions:The results of this study strongly indicate the protective effect of SXE against acute liver injun which may he attributed to its hepatoprotective activity,and there by scientifically support its traditional use.
文摘The term vertebrate is generally viewed by systematists in two contexts,either as Craniata(myxinoids or hagfishes+vertebrates s.s.,i.e.basically,animals possessing a stiff backbone)or as Vertebrata(lampreys+other vertebrae-bearing animals,which we propose to call here Euvertebrata).Craniates are characterized by a skull;vertebrates by vertebrae(arcualia);euvertebrates are vertebrates with hard phosphatised tissues in the skeleton.The earliest known possible craniate is Myllokunmingia(syn.Haikouichthys)from the Lower Cambrian of Chengjiang,south China.Euvertebrates appear in the Ordovician.C.H.Pander is sometimes thought to have been the first to propose that conodonts are vertebrates,but he did have doubts about the fish affinities of conodonts.This proposal was revived in the 30s and especially in the 80s of the 20th century and given elevated status in 2000 through a cladistic analysis based upon interpretation of conodont mineralized tissues as homologous to those of vertebrates.This analysis resolved conodonts within the clade Vertebrata s.s.,and incorporated a‘Total Group Concept’(TGC),including conodonts in the TG Gnathostomes(=jawed vertebrates).This resulted in the unusual scenario in which“teeth”appear before jaws.We reject the TGC nomenclature as applied to early vertebrates.In addition,based on all existing evidence,we consider that conodont hard tissues and several other anatomical structures in conodonts are not homologous with those of vertebrates.Making a revised cladistic analysis,eliminating characters unknown in fossils,conodonts appear stemward(i.e.more basal)to craniates and are thus interpreted as basal chordates at best.To help resolve the phylogenetic relationships of conodonts and chordates,the analysis should be extended to include non-chordate taxa.
