Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters acc...Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters accurately. This is a very difficult task especially if the manipulator is flexible. So a reduced model based controller has been developed, which requires only the information of space robot base velocity and link parameters. The flexible link is modeled as Euler Bernoulli beam. To simplify the analysis we have considered Jacobian of rigid manipulator. Bond graph modeling is used to model the dynamics of the system and to devise the control strategy. The scheme has been verified using simulation for two links flexible space manipulator.展开更多
Continuum manipulators(CM)are soft and flexible manipulators with large numbers of degrees of freedom and can perform complex tasks in an unstructured environment.However,their deformability and compliance can deviate...Continuum manipulators(CM)are soft and flexible manipulators with large numbers of degrees of freedom and can perform complex tasks in an unstructured environment.However,their deformability and compliance can deviate distal tip under uncertain external interactions.To address this challenge,a novel tension-based control scheme has been proposed to modulate the stiffness of a tendon-driven CM,reducing the tip position errors caused by uncertain external forces.To minimize the tip position error,a virtual spring is positioned between the deviated and the desired tip positions.The proposed algorithm corrects the manipulator deviated tip position,improving tension distribution and stiffness profile,resulting in higher stiffness and better performance.The corresponding task space stiffness and condition numbers are also computed under different cases,indicating the effectiveness of the tension control scheme in modulating the manipulator's stiffness.Experimental validation conducted on an in-house developed prototype confirms the practical feasibility of the proposed approach.展开更多
ESystems based on EHRs(Electronic health records)have been in use for many years and their amplified realizations have been felt recently.They still have been pioneering collections of massive volumes of health data.D...ESystems based on EHRs(Electronic health records)have been in use for many years and their amplified realizations have been felt recently.They still have been pioneering collections of massive volumes of health data.Duplicate detections involve discovering records referring to the same practical components,indicating tasks,which are generally dependent on several input parameters that experts yield.Record linkage specifies the issue of finding identical records across various data sources.The similarity existing between two records is characterized based on domain-based similarity functions over different features.De-duplication of one dataset or the linkage of multiple data sets has become a highly significant operation in the data processing stages of different data mining programmes.The objective is to match all the records associated with the same entity.Various measures have been in use for representing the quality and complexity about data linkage algorithms,and many other novel metrics have been introduced.An outline of the problem existing in themeasurement of data linkage and de-duplication quality and complexity is presented.This article focuses on the reprocessing of health data that is horizontally divided among data custodians,with the purpose of custodians giving similar features to sets of patients.The first step in this technique is about an automatic selection of training examples with superior quality from the compared record pairs and the second step involves training the reciprocal neuro-fuzzy inference system(RANFIS)classifier.Using the Optimal Threshold classifier,it is presumed that there is information about the original match status for all compared record pairs(i.e.,Ant Lion Optimization),and therefore an optimal threshold can be computed based on the respective RANFIS.Febrl,Clinical Decision(CD),and Cork Open Research Archive(CORA)data repository help analyze the proposed method with evaluated benchmarks with current techniques.展开更多
The Circular Restricted Three-Body Problem (CRTBP) with more massive primary as an oblate spheroid with its equatorial plane coincident with the plane of motion of the primaries is considered to generate the halo orbi...The Circular Restricted Three-Body Problem (CRTBP) with more massive primary as an oblate spheroid with its equatorial plane coincident with the plane of motion of the primaries is considered to generate the halo orbits around L1 and L2 for the seven satellites (Mimas, Enceladus, Tethys, Dione, Rhea, Titan and Iapetus) of Saturn in the frame work of CRTBP. It is found that the oblateness effect of Saturn on the halo orbits of the satellites closer to Saturn has significant effect compared to the satellites away from it. The halo orbits L1 and L2 are found to move towards Saturn with oblateness.展开更多
Highly crystalline ZSM-5 zeolites are important for para-selective alkylation of alkyl aromatics, because they carry few external acid sites for isomerization of p-dialkyl products. Such zeolites (Si/Al = 25, 50, and ...Highly crystalline ZSM-5 zeolites are important for para-selective alkylation of alkyl aromatics, because they carry few external acid sites for isomerization of p-dialkyl products. Such zeolites (Si/Al = 25, 50, and 75) were synthesized in a fluoride medium between pH 4 and 6. Their crystallinities, crystal sizes, and surface areas were higher than those of a commercial ZSM-5 zeolite. Their para selectivities in alkylation were tested for vapor-phase tert-butylation of ethylbenzene between 200 and 400 °C. As expected, all the catalysts showed more than 90% para selectivity. At 300 °C, ethylbenzene conversion decreased in the order ZSM-5(25, commercial) > ZSM-5(25) > ZSM-5(50) > ZSM-5(75). The catalysts had weak, medium, and strong acid sites, but all the acid sites of ZSM-5(75) were weaker than those of ZSM-5(25) and ZSM-5(50). The high activity of commercial ZSM-5 was caused by its strong acid sites being stronger than those of the synthesized zeolites. Although the activity of the commercial catalyst was higher than those of the present catalysts, the selectivity for 4-t-butylethylbenzene (4-t-BEB) was low. The optimum feed ratio (ethylbenzene:t-butyl alcohol) was 2:1 and the feed rate was 1.65 h?1 for high ethylbenzene conversion and 4-t-BEB selectivity. Time-on-stream studies showed slow catalyst deactivation. Highly crystalline ZSM-5 zeolites are therefore better than a commercial zeolite for para-selective alkylation of alkyl aromatics. They do not require much post-modification for high para selectivity. A fluoride medium is therefore better than an alkaline medium for obtaining highly crystalline para-selective ZSM-5 zeolites.展开更多
Testicular cancer seminoma is one of the most common types of cancer among men of reproductive age.Patients with this condition usually present reduced semen quality,even before initiating cancer therapy.However,the u...Testicular cancer seminoma is one of the most common types of cancer among men of reproductive age.Patients with this condition usually present reduced semen quality,even before initiating cancer therapy.However,the underlying mechanisms by which testicular cancer seminoma affects male fertility are largely unknown.The aim of this study was to investigate alterations in the sperm proteome of men with seminoma undergoing sperm banking before starting cancer therapy,in comparison to healthy proven fertile men(control group).A routine semen analysis was conducted before cryopreservation of the samples(n=15 per group).Men with seminoma showed a decrease in sperm motility(P=0.019),total motile count(P=0.001),concentration(P=0.003),and total sperm count(P=0.001).Quantitative proteomic analysis identified 393 differentially expressed proteins between the study groups.Ten proteins involved in spermatogenesis,sperm function,binding of sperm to the oocyte,and fertilization were selected for validation by western blot.We confirmed the underexpression of heat shock-related 70 kDa protein 2(P=0.041),ubiquinol-cytochrome C reductase core protein 2(P=0.026),and testis-specific sodium/potassium-transporting ATPase subunit alpha-4(P=0.016),as well as the overexpression of angiotensin I converting enzyme(P=0.005)in the seminoma group.The altered expression levels of these proteins are associated with spermatogenesis dysfunction,reduced sperm kinematics and motility,failure in capacitation and fertilization.The findings of this study may explain the decrease in the fertilizing ability of men with seminoma before starting cancer therapy.展开更多
In this paper, the issue of control of impact forces generated during the interaction between the hopping ro-bot toe and the ground while landing has been considered. The force thus generated can damage the robot alto...In this paper, the issue of control of impact forces generated during the interaction between the hopping ro-bot toe and the ground while landing has been considered. The force thus generated can damage the robot altogether. With the objective to control these impact forces, impedance control strategy has been applied to the hopping robot system. The dynamics pertaining to the impact between robot toe and ground has been modeled as in case of a ball bouncing on the ground. Bond Graph theory has been used for the modeling of the hopping robot system. Simulation results show that impact forces generated during the landing has been controlled to a specified limiting value. This model and the corresponding analysis can be further extended for understanding the dynamics involved in continuous hopping of robot with constant height and velocity control.展开更多
Objective:To investigate the antimicrobial activity of the selected marine green algae Ulva lactuca(U.lactuca),Cheatomorpha linoides and Helimeda macroloba against six strains of Gram-positive bacteria[Staphylococcus ...Objective:To investigate the antimicrobial activity of the selected marine green algae Ulva lactuca(U.lactuca),Cheatomorpha linoides and Helimeda macroloba against six strains of Gram-positive bacteria[Staphylococcus aureus(S.aureus),Bacillus subtilis and Lactobacillus acidophilus(L.acidophilus)]and Gram-negative bacteria[Escherichia coli,Pseudomonas aeruginosa(P.aeruginosa)and Proteus mirabilis].Methods:The selected green seaweed extracts were experimented with four different solvents(acetone,ethanol,methanol and chloroform)against the selected pathogens by using agar disc diffusion method.Results:The maximum activity(7 mm)was observed by the extract of U.lactuca against Proteus mirabilis by using methanol as a solvent and the lowest activity(2 mm)was recorded by the extract of U.lactuca against L.acidophilus by using chloroform as a solvent and ethanol extract against P.aeruginosa.The lowest activity(2 mm)was seen in the extract of Cheatomorpha linoides by using ethanol and methanol as a solvent against S.aureus.In Helimeda macroloba extract,the lowest activity was recorded against Escherichia coli by using chloroform as a solvent.The microbial strains S.aureus,P.aeruginosa,Bacillus subtilis and L.acidophilus were resistant to the chloroform and methanol of all selected seaweeds.Conclusions:Further study should be needed to identify the prime compound which is responsible for the activity against the selected pathogens especially those causing the human diseases.展开更多
This paper presents design and development of virtual objects to be used with haptic device PHANTOM Omni for motor rehabilitation by incorporating visual and haptic feedback. Developed predominantly for augmentation o...This paper presents design and development of virtual objects to be used with haptic device PHANTOM Omni for motor rehabilitation by incorporating visual and haptic feedback. Developed predominantly for augmentation of motor skill of patient, the objects could also be used for teaching and enhancing writing skill of children. The virtual objects include English alphabets, numbers, string and mazes, and games. The scheme has been evaluated on children from 11 to 14 years age. The experiment gives good results.展开更多
From the nutritional point of view, data on dietary fiber content, tannin and in vitro protein digestibility of processed millet is of importance, because millets are never eaten raw. Effects of commonly used traditio...From the nutritional point of view, data on dietary fiber content, tannin and in vitro protein digestibility of processed millet is of importance, because millets are never eaten raw. Effects of commonly used traditional methods on dietary fiber, tannin content and %IVPD of two locally available pearl millet varieties (Kalukombu and Maharashtra Rabi Bajra) were investigated. The millet was subjected to various processing methods like milling (whole flour, semi refined flour and bran rich fraction) roasting, boiling, pressure cooking & germination respectively. Processing had little effect on the total dietary fiber (TDF) content in both varieties;however the bran rich fraction showed highest TDF content of around 29%. Tannins effectively lowered upon boiling and pressure cooking respectively, but significantly increased (P ≥ 0.05) upon germination. Although the % IVPD of the millet (45.5 – 49.3 g/100g) was low, it significantly increased upon milling (bran rich fraction), roasting and germination respectively.展开更多
Objective:To purify and partially characterize the antimicrobial compounds from bacteriaBacillus sp.,isolated from fish gut.Methods:Protein and fatty acids were isolated from the bacteria and checked for the presence ...Objective:To purify and partially characterize the antimicrobial compounds from bacteriaBacillus sp.,isolated from fish gut.Methods:Protein and fatty acids were isolated from the bacteria and checked for the presence of antibacterial activity.Protein has been purified to apparent homogeneity from the supernatants of culture by means of ammonium sulphate precipitation followed by dialysis.Fourier transform infrared spectroscopy analyses were performed for proteins to identify the functional groups.Results:sulfate polyacrylamide gel electrophoresis.Fatty acids were extracted and subjected to gas chromatographic analysis.Conclusions:Protein showed an apparent molecular mass 56,47 and 39 kDa on sodium dodecyl acids and proteins which holds promise for the development of new drugs.The antimicrobial activity of the bacteria might be due to the presence of fatty acids and proteins which holds promise for the development of new drugs.展开更多
Antarctic cyanobacteria biodiversity was investigated by simultaneous sequencing of the nuclear ribosomal internal transcribed spacer (ITS flanked by partial 16S and 23S), and Chloroplast tRNALeu UAA intron (TrnL), ex...Antarctic cyanobacteria biodiversity was investigated by simultaneous sequencing of the nuclear ribosomal internal transcribed spacer (ITS flanked by partial 16S and 23S), and Chloroplast tRNALeu UAA intron (TrnL), exploring whether such morphotypes constitute distinct species and explaining their current distribution. We identified Nostocales, Chrococcales and Oscillatoriales species, collected in different habitats (soil, algal mats, lake sediments, ice-water) after their growth in cultures. By comparative sequence analyses available in Genbank, our results proved to be mostly in agreement with both TrnL and ITS, in the identification of the strains, particularly for Nostocales. Although ITS demonstrated more usefully than TrnL did in identifying Oscillatoriales and Chroococcales, due to the frequent lack of the intron in these groups, our results lead us to support an independent phylogenetic dataset of ITS and TrnL (the latter based on conserved regions) producing not only concordant clusters but also a secondary structure. Specific assignments of the secondary structure evidenced by different cyanobacteria groups, especially the D1-D1’ region of ITS and the P6b region of TrnL. For the latter region, the sequences analyzed for Nostoc species could be divided into the two classes previously identified, on the basis of different heptanucleotide repeats in P6b which were not展开更多
文摘Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters accurately. This is a very difficult task especially if the manipulator is flexible. So a reduced model based controller has been developed, which requires only the information of space robot base velocity and link parameters. The flexible link is modeled as Euler Bernoulli beam. To simplify the analysis we have considered Jacobian of rigid manipulator. Bond graph modeling is used to model the dynamics of the system and to devise the control strategy. The scheme has been verified using simulation for two links flexible space manipulator.
文摘Continuum manipulators(CM)are soft and flexible manipulators with large numbers of degrees of freedom and can perform complex tasks in an unstructured environment.However,their deformability and compliance can deviate distal tip under uncertain external interactions.To address this challenge,a novel tension-based control scheme has been proposed to modulate the stiffness of a tendon-driven CM,reducing the tip position errors caused by uncertain external forces.To minimize the tip position error,a virtual spring is positioned between the deviated and the desired tip positions.The proposed algorithm corrects the manipulator deviated tip position,improving tension distribution and stiffness profile,resulting in higher stiffness and better performance.The corresponding task space stiffness and condition numbers are also computed under different cases,indicating the effectiveness of the tension control scheme in modulating the manipulator's stiffness.Experimental validation conducted on an in-house developed prototype confirms the practical feasibility of the proposed approach.
基金This research project was funded by Princess Nourah bint Abdulrahman University Researchers Supporting Project Number(PNURSP2022R234),Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘ESystems based on EHRs(Electronic health records)have been in use for many years and their amplified realizations have been felt recently.They still have been pioneering collections of massive volumes of health data.Duplicate detections involve discovering records referring to the same practical components,indicating tasks,which are generally dependent on several input parameters that experts yield.Record linkage specifies the issue of finding identical records across various data sources.The similarity existing between two records is characterized based on domain-based similarity functions over different features.De-duplication of one dataset or the linkage of multiple data sets has become a highly significant operation in the data processing stages of different data mining programmes.The objective is to match all the records associated with the same entity.Various measures have been in use for representing the quality and complexity about data linkage algorithms,and many other novel metrics have been introduced.An outline of the problem existing in themeasurement of data linkage and de-duplication quality and complexity is presented.This article focuses on the reprocessing of health data that is horizontally divided among data custodians,with the purpose of custodians giving similar features to sets of patients.The first step in this technique is about an automatic selection of training examples with superior quality from the compared record pairs and the second step involves training the reciprocal neuro-fuzzy inference system(RANFIS)classifier.Using the Optimal Threshold classifier,it is presumed that there is information about the original match status for all compared record pairs(i.e.,Ant Lion Optimization),and therefore an optimal threshold can be computed based on the respective RANFIS.Febrl,Clinical Decision(CD),and Cork Open Research Archive(CORA)data repository help analyze the proposed method with evaluated benchmarks with current techniques.
文摘The Circular Restricted Three-Body Problem (CRTBP) with more massive primary as an oblate spheroid with its equatorial plane coincident with the plane of motion of the primaries is considered to generate the halo orbits around L1 and L2 for the seven satellites (Mimas, Enceladus, Tethys, Dione, Rhea, Titan and Iapetus) of Saturn in the frame work of CRTBP. It is found that the oblateness effect of Saturn on the halo orbits of the satellites closer to Saturn has significant effect compared to the satellites away from it. The halo orbits L1 and L2 are found to move towards Saturn with oblateness.
基金supported by grants from Korea CCSR&D Centre,funded by the Ministry of Education,Science and Technology of the Korean Government
文摘Highly crystalline ZSM-5 zeolites are important for para-selective alkylation of alkyl aromatics, because they carry few external acid sites for isomerization of p-dialkyl products. Such zeolites (Si/Al = 25, 50, and 75) were synthesized in a fluoride medium between pH 4 and 6. Their crystallinities, crystal sizes, and surface areas were higher than those of a commercial ZSM-5 zeolite. Their para selectivities in alkylation were tested for vapor-phase tert-butylation of ethylbenzene between 200 and 400 °C. As expected, all the catalysts showed more than 90% para selectivity. At 300 °C, ethylbenzene conversion decreased in the order ZSM-5(25, commercial) > ZSM-5(25) > ZSM-5(50) > ZSM-5(75). The catalysts had weak, medium, and strong acid sites, but all the acid sites of ZSM-5(75) were weaker than those of ZSM-5(25) and ZSM-5(50). The high activity of commercial ZSM-5 was caused by its strong acid sites being stronger than those of the synthesized zeolites. Although the activity of the commercial catalyst was higher than those of the present catalysts, the selectivity for 4-t-butylethylbenzene (4-t-BEB) was low. The optimum feed ratio (ethylbenzene:t-butyl alcohol) was 2:1 and the feed rate was 1.65 h?1 for high ethylbenzene conversion and 4-t-BEB selectivity. Time-on-stream studies showed slow catalyst deactivation. Highly crystalline ZSM-5 zeolites are therefore better than a commercial zeolite for para-selective alkylation of alkyl aromatics. They do not require much post-modification for high para selectivity. A fluoride medium is therefore better than an alkaline medium for obtaining highly crystalline para-selective ZSM-5 zeolites.
基金Financial support for this study was provided by the American Center for Reproductive Medicine,Cleveland Clinic,OH,USATania R Dias was supported by the Portuguese Foundation for Science and Technology(FCT,SFRH/BD/109284/2015)Fulbright Program(E0585639).
文摘Testicular cancer seminoma is one of the most common types of cancer among men of reproductive age.Patients with this condition usually present reduced semen quality,even before initiating cancer therapy.However,the underlying mechanisms by which testicular cancer seminoma affects male fertility are largely unknown.The aim of this study was to investigate alterations in the sperm proteome of men with seminoma undergoing sperm banking before starting cancer therapy,in comparison to healthy proven fertile men(control group).A routine semen analysis was conducted before cryopreservation of the samples(n=15 per group).Men with seminoma showed a decrease in sperm motility(P=0.019),total motile count(P=0.001),concentration(P=0.003),and total sperm count(P=0.001).Quantitative proteomic analysis identified 393 differentially expressed proteins between the study groups.Ten proteins involved in spermatogenesis,sperm function,binding of sperm to the oocyte,and fertilization were selected for validation by western blot.We confirmed the underexpression of heat shock-related 70 kDa protein 2(P=0.041),ubiquinol-cytochrome C reductase core protein 2(P=0.026),and testis-specific sodium/potassium-transporting ATPase subunit alpha-4(P=0.016),as well as the overexpression of angiotensin I converting enzyme(P=0.005)in the seminoma group.The altered expression levels of these proteins are associated with spermatogenesis dysfunction,reduced sperm kinematics and motility,failure in capacitation and fertilization.The findings of this study may explain the decrease in the fertilizing ability of men with seminoma before starting cancer therapy.
文摘In this paper, the issue of control of impact forces generated during the interaction between the hopping ro-bot toe and the ground while landing has been considered. The force thus generated can damage the robot altogether. With the objective to control these impact forces, impedance control strategy has been applied to the hopping robot system. The dynamics pertaining to the impact between robot toe and ground has been modeled as in case of a ball bouncing on the ground. Bond Graph theory has been used for the modeling of the hopping robot system. Simulation results show that impact forces generated during the landing has been controlled to a specified limiting value. This model and the corresponding analysis can be further extended for understanding the dynamics involved in continuous hopping of robot with constant height and velocity control.
基金Supported by University Grants Commission,Government of India under major research project[Grant No.41–120/2012(SR)].
文摘Objective:To investigate the antimicrobial activity of the selected marine green algae Ulva lactuca(U.lactuca),Cheatomorpha linoides and Helimeda macroloba against six strains of Gram-positive bacteria[Staphylococcus aureus(S.aureus),Bacillus subtilis and Lactobacillus acidophilus(L.acidophilus)]and Gram-negative bacteria[Escherichia coli,Pseudomonas aeruginosa(P.aeruginosa)and Proteus mirabilis].Methods:The selected green seaweed extracts were experimented with four different solvents(acetone,ethanol,methanol and chloroform)against the selected pathogens by using agar disc diffusion method.Results:The maximum activity(7 mm)was observed by the extract of U.lactuca against Proteus mirabilis by using methanol as a solvent and the lowest activity(2 mm)was recorded by the extract of U.lactuca against L.acidophilus by using chloroform as a solvent and ethanol extract against P.aeruginosa.The lowest activity(2 mm)was seen in the extract of Cheatomorpha linoides by using ethanol and methanol as a solvent against S.aureus.In Helimeda macroloba extract,the lowest activity was recorded against Escherichia coli by using chloroform as a solvent.The microbial strains S.aureus,P.aeruginosa,Bacillus subtilis and L.acidophilus were resistant to the chloroform and methanol of all selected seaweeds.Conclusions:Further study should be needed to identify the prime compound which is responsible for the activity against the selected pathogens especially those causing the human diseases.
文摘This paper presents design and development of virtual objects to be used with haptic device PHANTOM Omni for motor rehabilitation by incorporating visual and haptic feedback. Developed predominantly for augmentation of motor skill of patient, the objects could also be used for teaching and enhancing writing skill of children. The virtual objects include English alphabets, numbers, string and mazes, and games. The scheme has been evaluated on children from 11 to 14 years age. The experiment gives good results.
文摘From the nutritional point of view, data on dietary fiber content, tannin and in vitro protein digestibility of processed millet is of importance, because millets are never eaten raw. Effects of commonly used traditional methods on dietary fiber, tannin content and %IVPD of two locally available pearl millet varieties (Kalukombu and Maharashtra Rabi Bajra) were investigated. The millet was subjected to various processing methods like milling (whole flour, semi refined flour and bran rich fraction) roasting, boiling, pressure cooking & germination respectively. Processing had little effect on the total dietary fiber (TDF) content in both varieties;however the bran rich fraction showed highest TDF content of around 29%. Tannins effectively lowered upon boiling and pressure cooking respectively, but significantly increased (P ≥ 0.05) upon germination. Although the % IVPD of the millet (45.5 – 49.3 g/100g) was low, it significantly increased upon milling (bran rich fraction), roasting and germination respectively.
基金Supported by Department of science and technology with grant number-IF10573.
文摘Objective:To purify and partially characterize the antimicrobial compounds from bacteriaBacillus sp.,isolated from fish gut.Methods:Protein and fatty acids were isolated from the bacteria and checked for the presence of antibacterial activity.Protein has been purified to apparent homogeneity from the supernatants of culture by means of ammonium sulphate precipitation followed by dialysis.Fourier transform infrared spectroscopy analyses were performed for proteins to identify the functional groups.Results:sulfate polyacrylamide gel electrophoresis.Fatty acids were extracted and subjected to gas chromatographic analysis.Conclusions:Protein showed an apparent molecular mass 56,47 and 39 kDa on sodium dodecyl acids and proteins which holds promise for the development of new drugs.The antimicrobial activity of the bacteria might be due to the presence of fatty acids and proteins which holds promise for the development of new drugs.
文摘Antarctic cyanobacteria biodiversity was investigated by simultaneous sequencing of the nuclear ribosomal internal transcribed spacer (ITS flanked by partial 16S and 23S), and Chloroplast tRNALeu UAA intron (TrnL), exploring whether such morphotypes constitute distinct species and explaining their current distribution. We identified Nostocales, Chrococcales and Oscillatoriales species, collected in different habitats (soil, algal mats, lake sediments, ice-water) after their growth in cultures. By comparative sequence analyses available in Genbank, our results proved to be mostly in agreement with both TrnL and ITS, in the identification of the strains, particularly for Nostocales. Although ITS demonstrated more usefully than TrnL did in identifying Oscillatoriales and Chroococcales, due to the frequent lack of the intron in these groups, our results lead us to support an independent phylogenetic dataset of ITS and TrnL (the latter based on conserved regions) producing not only concordant clusters but also a secondary structure. Specific assignments of the secondary structure evidenced by different cyanobacteria groups, especially the D1-D1’ region of ITS and the P6b region of TrnL. For the latter region, the sequences analyzed for Nostoc species could be divided into the two classes previously identified, on the basis of different heptanucleotide repeats in P6b which were not
