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Changes in land use due to urbanization, industrialization, and agriculture will adversely affect water quality at all scales. This study examined the possible effects of future land use on the water quality of the Dez River located in Iran. The QUAL2Kw dynamic model was used to simulate the water quality of the Dez River. Data and information available in July 2019 and 2013 were used for calibration and validation. According to the comparison of the RMSE, RMSE%, and percent bias error indices for the model during the calibration and validation period, the QUAL2Kw model of Dez River had high accuracy with acceptable values of errors. The land use changes in the Dez river basin were modeled and predicted by the LCM model after simulating water quality. The images from Landsat 8/OLI were used for 2013, 2016, and 2019, respectively. Based on the accurate evaluation of classified images, Kappa coefficients for 2013, 2016, and 2019 were 88.19, 87.46, and 89.91, respectively. Modeling land use and land cover changes was conducted to predict 2030. As a result of the study, agricultural and built-up areas and water bodies will increase in 2030. The possible effects of land use changes in 2030 on river water quality were examined as a final step. Based on the results of the water quality simulation in 2030, biochemical oxygen demand, chemical oxygen demand, and NO3 parameters exceeded the maximum permissible level of drinking standard. This study recommends frequent water quality monitoring and LULC planning and management to reduce pollution in river basins.
Assuntos
Rios , Qualidade da Água , Monitoramento Ambiental/métodos , Urbanização , AgriculturaRESUMO
Cold Spray (CS) is a deposition process, part of the thermal spray family. In this method, powder particles are accelerated at supersonic speed within a nozzle; impacts against a substrate material triggers a complex process, ultimately leading to consolidation and bonding. CS, in its modern form, has been around for approximately 30 years and has undergone through exciting and unprecedented developmental steps. In this article, we have summarized the key inventions and sub-inventions which pioneered the innovation aspect to the process that is known today, and the key breakthroughs related to the processing of materials CS is currently mastering. CS has not followed a liner path since its invention, but an evolution more similar to a hype cycle: high initial growth of expectations, followed by a decrease in interest and a renewed thrust pushed by a number of demonstrated industrial applications. The process interest is expected to continue (gently) to grow, alongside with further development of equipment and feedstock materials specific for CS processing. A number of current applications have been identified the areas that the process is likely to be the most disruptive in the medium-long term future have been laid down.
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BACKGROUND: Recently, much attention has been paid to use circulating microRNAs (miRs) as a non-invasive tumor marker. The present study for the first time was designed to evaluate concurrent use of miR-21, miR-638, miR148 and miR-152 as putative diagnostic tool for detection of non-small cell lung carcinoma (NSCLC). METHODS: Forty-three patients diagnosed as primary NSCLC was included in this study. The level of selected miRs was measured in whole blood specimens of patients and controls. The corresponding values were also obtained in stages I-IV. We also assessed possible correlation between selected miRs and the clinicopathological findings of studied individuals. RESULTS: miR-21 was increased in patients compared to controls (P = 0.004). In contrast, circulating miR-638, miR-148 and miR-152 was observed to be down-regulated in NSCLC patients than controls (P = 0.001, 0.003, 0.053, respectively). Rise in miR-21-5p expression and decreased blood level of miR-148a-3p was associated with higher stage of NSCLC. The highest sensitivity (90%) was observed for miR-21 while miR-148 had the highest specificity (71%). The corresponding sensitivity and specificity for combined-miRs-panel was 96.4% and 86.67%, respectively. CONCLUSION: In summary, our data suggested the diagnostic importance of combined-miR-panel including miR-21, miR-638, miR148 and miR-152 for effective discrimination of NSCLC from non-cancerous subjects.
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Carcinoma Pulmonar de Células não Pequenas/diagnóstico , MicroRNA Circulante/sangue , Neoplasias Pulmonares/diagnóstico , Idoso , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e EspecificidadeRESUMO
The increase in patient temperature during hemodialysis is explained by hemodynamic compensation during ultrafiltration and hypovolemia that leads to peripheral vasoconstriction and reduced heat losses. We analyzed 51 stable high-efficiency hemodialysis treatments in 27 patients during isothermic dialysis in which body temperature was maintained at a constant level (+/-0.1 degrees C) using the temperature-control option of the Blood Temperature Monitor (BTM; Fresenius Medical Care, Bad Homburg, Germany). Hemodialysis was delivered using ultrapure water (limulus amebocyte lysate test < 0. 06 endotoxin units/mL) at mean blood flows of 410 +/- 40 mL/min. During treatments lasting 178 +/- 23 minutes, 4.8% +/- 1.4% of postdialysis body weight (W%) and 9.5% +/- 2.5% of postdialysis body water were removed using mean ultrafiltration rates of 1.1 +/- 0.3 L/h. Dialysate temperatures significantly decreased from 35.9 degrees C +/- 0.3 degrees C to 35.6 degrees C +/- 0.6 degrees C during hemodialysis. During these treatments, 187 +/- 69 kJ of thermal energy were removed from the patients through the extracorporeal circulation using cool dialysate. Extracorporeal heat flow was 17 +/- 6 W. Energy expenditure (H) estimated from anthropometric data was 65 +/- 12 W. Thus, 28% +/- 10% of estimated energy expenditure (H%) was removed during isothermic dialysis. A highly significant correlation was observed between H% and W% (H% = -5.6 * W%; r(2) = 0.91; P < 0.0001). This result is in support of the volume hypothesis of intradialytic heat accumulation and provides a rule of thumb to estimate extracorporeal cooling requirements for isothermic dialysis. Approximately 6% of H must be removed through the extracorporeal circulation for each percent of ultrafiltration-induced body-weight change. The importance of body temperature control during hemodialysis increases with increased ultrafiltration requirements.
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Temperatura Corporal , Diálise Renal/métodos , Temperatura , Peso Corporal , Metabolismo Energético , Feminino , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Using proper technique in different sports is an inevitable factor. In this study, available techniques for snatch weightlifting are mathematically evaluated. The optimal motion trajectory is a technique used by weightlifters, which could be determined based on minimizing specific object functions. Object functions based on total kinetic energy, total torque and total power and some new multiobjective functions are minimized using genetic algorithm and the minimax principle. Some important motion characteristics of 13 professional weightlifters were extracted and used to validate the mathematical results. The double knee bending (DKB) technique was studied as a benchmark test. Some important movement features of the technique were shown by the mathematical analysis when applying an object function, that minimized joint torques and powers of different muscles independently. An object function based on joint forces did not show these features.
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Força Muscular/fisiologia , Levantamento de Peso/fisiologia , Algoritmos , Fenômenos Biomecânicos , Exercício Físico , Humanos , Articulações/fisiologia , Articulação do Joelho/fisiologia , Modelos Teóricos , Destreza Motora/fisiologia , Movimento/fisiologia , Postura , TorqueRESUMO
RNase D was recently reported as a new enzymatic activity associated with HIV-1 reverse transcriptase (RT), cleaving RNA at two positions within the double-stranded region of the tRNA primer-viral RNA template complex (Ben-Artzi et al., Proc. Natl. Acad. Sci. USA 89 (1992) 927-931). This would make RNase D a fourth distinct activity of HIV-1 RT, in addition to RNA- and DNA-dependent DNA polymerase and RNase H. Using a specific substrate containing tRNA(Lys,3) hybridized to the primer binding site, we were able to detect the reported RNase D activity in our preparations of recombinant HIV-1 RT. This activity was also present in several active-site mutants of RT, suggesting that it is independent of the RNase H and polymerase functionalities of RT. Furthermore, we found that the cleavage specificity of RNase D is the same as that of RNase III isolated from E.coli. A likely explantation of these results--that the observed RNase D activity is attributable to traces of RNase III contamination--was further strengthened by the finding that the recombinant preparations of HIV-1 RT can specifically cleave a phage T7-derived double-stranded RNA processing signal, which has been used as a model substrate for detection of E.coli RNase III. Moreover, RT purified from an RNase III- strain of E.coli displayed no cleavage of the tRNA primer-RNA template complex.
Assuntos
Endorribonucleases/metabolismo , Proteínas de Escherichia coli , Escherichia coli/enzimologia , HIV-1/enzimologia , DNA Polimerase Dirigida por RNA/metabolismo , Bacteriófago T7/enzimologia , Sequência de Bases , Sítios de Ligação , Transcriptase Reversa do HIV , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Processamento Pós-Transcricional do RNA , RNA de Cadeia Dupla/metabolismo , RNA de Transferência de Lisina/metabolismo , Proteínas Recombinantes/metabolismo , Ribonuclease III , Especificidade por SubstratoRESUMO
Knotted DNA has potentially devastating effects on cells. By using two site-specific recombination systems, we tied all biologically significant simple DNA knots in Escherichia coli. When topoisomerase IV activity was blocked, either with a drug or in a temperature-sensitive mutant, the knotted recombination intermediates accumulated whether or not gyrase was active. In contrast to its decatenation activity, which is strongly affected by DNA supercoiling, topoisomerase IV unknotted DNA independently of supercoiling. This differential supercoiling effect held true regardless of the relative sizes of the catenanes and knots. Finally, topoisomerase IV unknotted DNA equally well when DNA replication was blocked with hydroxyurea. We conclude that topoisomerase IV, not gyrase, unknots DNA and that it is able to access DNA in the cell freely. With these results, it is now possible to assign completely the topological roles of the topoisomerases in E. coli. It is clear that the topoisomerases in the cell have distinct and nonoverlapping roles. Consequently, our results suggest limitations in assigning a physiological function to a protein based upon sequence similarity or even upon in vitro biochemical activity.
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DNA Topoisomerases Tipo II/metabolismo , DNA Topoisomerases Tipo II/fisiologia , DNA/química , Escherichia coli/enzimologia , Conformação de Ácido Nucleico , DNA/metabolismo , DNA Girase , DNA Topoisomerase IV , DNA Topoisomerases Tipo II/genética , DNA Super-Helicoidal/química , Escherichia coli/genética , Modelos Biológicos , Plasmídeos/química , Recombinação Genética , Temperatura , Fatores de TempoRESUMO
The crystal structure of the catalytic domain of rat DNA polymerase beta revealed that Asp256 is located in proximity to the previously identified active site residues Asp190 and Asp192. We have prepared and kinetically characterized the nucleotidyl transfer activity of wild type and several mutant forms of human and rat pol beta. Herein we report steady-state kinetic determinations of KmdTTP, Km(dT)16, and kcat for mutants in residue Asp256 and two neighboring residues, Arg254 and Arg258, all centrally located on strand beta 7 in the pol beta structure. Mutation of Asp256 to alanine abolished the enzymatic activity of pol beta. Conservative replacement with glutamic acid (D256E) led to a 320-fold reduction of kcat compared to wild type. Replacement of Arg254 with an alanine (R254A) resulted in a 50-fold reduction of kcat compared to wild type. The Km(dT)16 of D256E and R254A increased about 18-fold relative to wild type. Replacement of Arg254 with a lysine resulted in a 15-fold decrease in kcat, and a 5-fold increase in the Km(dT)16. These kinetic observations support a role of Asp256 and Arg254 in the positioning of divalent metal ions and substrates in precise geometrical orientation for efficient catalysis. The mutation of Arg258 to alanine (R258A) resulted in a 10-fold increase in KmdTTP and a 65-fold increase in Km(dT)16 but resulted in no change of kcat. These observations are discussed in the context of the three-dimensional structures of the catalytic domain of pol beta and the ternary complex of pol beta, ddCTP, and DNA.