The objective of this study was to determine the effect of supplementation with a protected fat source on the productive response, metabolic environment and physiological indicators in Holstein cows under heat stress ...The objective of this study was to determine the effect of supplementation with a protected fat source on the productive response, metabolic environment and physiological indicators in Holstein cows under heat stress conditions during a 12-week experimental period. Thirty Holstein cows were distributed in 15 blocks by parity (2.0 ± 1.1), days in milk (182 ± 80) and milk production (29.4 ± 5.7 kg·day<sup>-</sup><sup>1</sup>) at the beginning of the trial and randomly assigned within each block to the following treatments (diets): SPF: supplementation with protected fat or WPF: without supplementation with protected fat. All the cows were kept in a dry-lot where they were given a partial mixed ration (PMR) ad libitum while in the milking parlor they received individual supplementation depending on the treatment. The SPF diet contained 4.0 kg·day<sup>-</sup><sup>1</sup> concentrate in pellet form + 0.6 kg·day<sup>-1</sup> ground corn grain + 0.7 kg·day<sup>-</sup><sup>1</sup> protected fat, while the WPF diet was similar to that offered in SPF, but the protected fat was isoenergetically replaced by ground corn grain. The fat supplement contained fats of animal and vegetable origin and microencapsulation was used for its preparation. Total dry matter and metabolic energy intakes were similar (p > 0.05) between treatments. Fat corrected milk (4% FCM) production was higher (p = 0.04), while energy corrected milk and fat productions tended (p = 0.06) to be higher in cows from the SPF group, without effects (p > 0.05) on the rest of the milk production and composition parameters. These results could be attributed to an improvement in the efficiency of the use of the energy consumed. Protected fat supplementation neither modified the metabolic profile, nor reduced the respiratory rate and body temperature of heat-stressed cows. Future research is needed to explain this latter result.展开更多
Background: To compare the neuropsychological consequences after carotid artery stenting (CAS) and extracranial-intracranial by-pass (EC-IC by-pass). Methods: A total of 43 patients referred to CAS, 32 patients referr...Background: To compare the neuropsychological consequences after carotid artery stenting (CAS) and extracranial-intracranial by-pass (EC-IC by-pass). Methods: A total of 43 patients referred to CAS, 32 patients referred to EC-IC by-pass and 43 control subjects were enrolled in the study. Neuropsychologic testing was performed before and three months after procedure. A paired Student t test was used to compare neuropsychologic test scores at baseline and three months after procedure in each group. Cognitive changes in a three-month follow-up were not normally distributed and compared among/between groups with Kruskal-Wallis test. Results: Three months after the treatment both the CAS and EC-IC by-pass groups showed improved cognitive performance compared to baseline, whereas the same improvement wasn’t seen in the control group. The scores from Activities of Daily Living also improved in all three groups in a three-month follow-up, and EC-IC group presented a more distinct increase in daily life abilities comparing to the other two groups. Conclusions: CAS and EC-IC by-pass in patients with a carotid or intracranial stenosis may result in cognitive improvement three months after surgery.展开更多
The transition process of the boundary layer developing over a flat plate with elevated inlet Free Stream Turbulence Intensity(FSTI)has been studied by means of Large Eddy Simulation(LES).To this purpose,four cases wi...The transition process of the boundary layer developing over a flat plate with elevated inlet Free Stream Turbulence Intensity(FSTI)has been studied by means of Large Eddy Simulation(LES).To this purpose,four cases with different inflow disturbances have been tested varying the magnitude and the length scale of turbulence.LES has been performed by using the finite-volume ANSYS Fluent code.The computational domain,which was constituted by a rectangular domain with a zero thickness plate,was based on an ERCOFTAC test case in order to provide a validation with a well-known set of data by comparing the boundary layer integral parameters and mean and fluctuating streamwise velocity profiles.The four cases were discussed within the paper by looking at classical statistical properties as well as advanced post-processing tools.It was shown that the decrease in the free stream turbulence level postpones the transition location,whereas the variation of the integral length scale has a very low influence on the distribution of the time-mean flow properties.Proper Orthogonal Decomposition(POD)has been applied to the instantaneous LES flow fields in order to provide a statistical representation of the structures responsible for transition and their response to free-stream turbulence intensity and length scale.The presence of vortical filaments parallel to the wall,typically referred as boundary layer streaks,is clearly identified;their characteristic dimensions and how they change as a function of FSTI properties were analyzed within the paper.展开更多
Objectives: The main steps for physiologic type reconstruction in 50 complicated corrosive strictures of upper alimentary tract are presented. Methods: In successive developed gastric outlet and esophageal strictures ...Objectives: The main steps for physiologic type reconstruction in 50 complicated corrosive strictures of upper alimentary tract are presented. Methods: In successive developed gastric outlet and esophageal strictures a limited Billroth I resection (in 9) or conversion a prior precolic GEA in such anastomosis (in 5) and middle or total gastrectomies (in 3) were performed. A second stage substernal by-pass with isoperistaltic transverse colon segment was done 6 - 12 weeks later. In all but one instances the graft was implanted high in the gastric stump. In extensive burned and retracted such lesion (in 3) a similar by-pass was carried out but the lower anastomosis was done with the not involved prepyloric segement. In concomittant antropyloric and esophageal strictures in 11 young, good risk patients, a limited Billroth I resction and simultaneous colonic bypass was used. In case of accompanied respiratory fistula (in 4) exclusion by-pass was useful for both lesions. The associated pyloric stricture (in 3) was solved at the same time. Side-to-end pharyngocolostomy was used in 4 high thoracocervical strictures. In 8 previously perforated strictures the by-ass was performed 2 months later. Reults: The overall mortality was 4%. The postoperative morbidity was low (8%). All cervical leaks closed spontaneously. Particular late complications required revisional surgery in 12, 5% of cases. Conclusion: In complicated corrosive strictures (esophageal, gastric, fistulas) limited Billoth I resection, isoperistaltic colon by-pass with high gastrocolic anastomosis, good gastric drainage and maintenance of the duodenum in gastrointestinal continuity are the main factors to achieve the best functional results.展开更多
<em>Objective</em>: In order to take a decision about the revascularization approach to be adopted, it is of fundamental importance to determine whether coronary artery stenoses induce ischemia or not. An ...<em>Objective</em>: In order to take a decision about the revascularization approach to be adopted, it is of fundamental importance to determine whether coronary artery stenoses induce ischemia or not. An index, named (Fractional Flow Reserve), based on pressure measurements has been proposed to this aim and is usually interpreted in terms of flows. The objective of this work is to compute simultaneously pressures and flow rates in the coronary network of patients with three-vessel disease, in order to study more precisely the relationship between these two quantities. <em>Approach</em>: 22 patients have been included in the study. Some pressure and flow rate measurements were collected during by-pass surgery. These clinical data allow determining parameters for a patient’s specific model, based on the electric/hydraulic analogy. Collateral pathways are included in the model, as well as the severity of the disease and the impact of revascularization. <em>Main Results</em>: For patients with stenoses on LAD, LCx, LMCA and occlusion of the RCA, the flow rate delivered to the right territory is of course a function of the aortic pressure, the left stenoses severity, and the pressure distal to the thrombosis. But it mainly depends on the capillary and collateral resistances, and on the proportion between them. Abnormal microvascular hemodynamics, may be present in patients with non-hemodynamic significant lesions as assessed by the pressure ratio. Complete revascularization with the 3 grafts is demonstrated to be fully justified. The direction of collateral flows may be reversed, depending on the pressure gradient. In any case, they remain low and become negligible when the 3 grafts are operating. <em>Significance</em>: Surgical decision based only on pressure measurements may miss some real hemodynamic problems due to the considered stenosis. This risk is even greater in case of serial stenoses.展开更多
Ventricular fibrillation seen just after declamping of the aorta is an undesirable condition causing myocardial injury. To return to normal rhythm, often internal shocks are applied. But defibrillation itself can also...Ventricular fibrillation seen just after declamping of the aorta is an undesirable condition causing myocardial injury. To return to normal rhythm, often internal shocks are applied. But defibrillation itself can also contribute to myocardial injury. So prevention of fibrillation is more important than treatment. 236 patients undergoing coronary artery by-pass surgery were included in this retrospective clinical study. 144 of those patients were operated using modified St. Thomas’ Hospital cardioplegic solution, for stopping the heart. In the other 92 patients, plegisol cardioplegic solution was used. We compared the two groups for the development of ventricular fibrilation after declamping of the aorta. In the modified St. Thomas’ Hospital group, ventricular fibrillation after declamping of the aorta was seen less frequently, this being statistically significant (22.2% vs. 52.2%, p = 0.026). This study shows that the modified St.Thomas’ Hospital cardioplegic solution is preferred for avoiding ventricular fibrillation occuring just after declamping of the aorta.展开更多
Cement kiln co-processing techniques have been developed in the past 20 years in China,and more than 60 factories now use fermentation,screening,and gasification pre-treatment techniques to coprocess municipal solid w...Cement kiln co-processing techniques have been developed in the past 20 years in China,and more than 60 factories now use fermentation,screening,and gasification pre-treatment techniques to coprocess municipal solid waste(MSW).There three complete MSW pre-treatment techniques,coprocessing procedures,and environmental risk assessments have been described in few publications.In this study,we assessed the effectiveness of each technique.The results suggested that the pollutant content released by each pre-treatment technology was lower than the emission standard.To reveal the mechanisms of pollutant migration and enrichment,the substances in the kiln and kiln products are investigated.The input of co-processing materials(Co-M)produced by fermentation caused formation of polychlorinated dibenzo-p-dioxins and dibenzoftiran(PCDD/Fs)in the bypass flue gas(By-gas)in excess of the regulatory standard.The Co-M input produced by the screening and gasifier technologies caused the total organic carbon(TOC)concentration to exceed the standard.In addition,the NOx,TOC,and PCDD/Fs in the By-gas exceeded the regulatory standard.Raw meal was the primary chlorine and heavy metals input stream,and clinker(CK)and cement kiln dust(CKD)accounted for>90%of the total chlorine output stream.Flue gas and CKD were the primary volatile heavy metal(Hg)output streams.Greater than 70%of the semi-volatile heavy metals(Cd,Pb,T1 and Se)distributed in hot raw meal and bypass cement kiln dust.The low-volatility heavy metals were concentrated in the CK.These results indicated that co-processing techniques used in China still require improvement.展开更多
文摘The objective of this study was to determine the effect of supplementation with a protected fat source on the productive response, metabolic environment and physiological indicators in Holstein cows under heat stress conditions during a 12-week experimental period. Thirty Holstein cows were distributed in 15 blocks by parity (2.0 ± 1.1), days in milk (182 ± 80) and milk production (29.4 ± 5.7 kg·day<sup>-</sup><sup>1</sup>) at the beginning of the trial and randomly assigned within each block to the following treatments (diets): SPF: supplementation with protected fat or WPF: without supplementation with protected fat. All the cows were kept in a dry-lot where they were given a partial mixed ration (PMR) ad libitum while in the milking parlor they received individual supplementation depending on the treatment. The SPF diet contained 4.0 kg·day<sup>-</sup><sup>1</sup> concentrate in pellet form + 0.6 kg·day<sup>-1</sup> ground corn grain + 0.7 kg·day<sup>-</sup><sup>1</sup> protected fat, while the WPF diet was similar to that offered in SPF, but the protected fat was isoenergetically replaced by ground corn grain. The fat supplement contained fats of animal and vegetable origin and microencapsulation was used for its preparation. Total dry matter and metabolic energy intakes were similar (p > 0.05) between treatments. Fat corrected milk (4% FCM) production was higher (p = 0.04), while energy corrected milk and fat productions tended (p = 0.06) to be higher in cows from the SPF group, without effects (p > 0.05) on the rest of the milk production and composition parameters. These results could be attributed to an improvement in the efficiency of the use of the energy consumed. Protected fat supplementation neither modified the metabolic profile, nor reduced the respiratory rate and body temperature of heat-stressed cows. Future research is needed to explain this latter result.
文摘Background: To compare the neuropsychological consequences after carotid artery stenting (CAS) and extracranial-intracranial by-pass (EC-IC by-pass). Methods: A total of 43 patients referred to CAS, 32 patients referred to EC-IC by-pass and 43 control subjects were enrolled in the study. Neuropsychologic testing was performed before and three months after procedure. A paired Student t test was used to compare neuropsychologic test scores at baseline and three months after procedure in each group. Cognitive changes in a three-month follow-up were not normally distributed and compared among/between groups with Kruskal-Wallis test. Results: Three months after the treatment both the CAS and EC-IC by-pass groups showed improved cognitive performance compared to baseline, whereas the same improvement wasn’t seen in the control group. The scores from Activities of Daily Living also improved in all three groups in a three-month follow-up, and EC-IC group presented a more distinct increase in daily life abilities comparing to the other two groups. Conclusions: CAS and EC-IC by-pass in patients with a carotid or intracranial stenosis may result in cognitive improvement three months after surgery.
文摘The transition process of the boundary layer developing over a flat plate with elevated inlet Free Stream Turbulence Intensity(FSTI)has been studied by means of Large Eddy Simulation(LES).To this purpose,four cases with different inflow disturbances have been tested varying the magnitude and the length scale of turbulence.LES has been performed by using the finite-volume ANSYS Fluent code.The computational domain,which was constituted by a rectangular domain with a zero thickness plate,was based on an ERCOFTAC test case in order to provide a validation with a well-known set of data by comparing the boundary layer integral parameters and mean and fluctuating streamwise velocity profiles.The four cases were discussed within the paper by looking at classical statistical properties as well as advanced post-processing tools.It was shown that the decrease in the free stream turbulence level postpones the transition location,whereas the variation of the integral length scale has a very low influence on the distribution of the time-mean flow properties.Proper Orthogonal Decomposition(POD)has been applied to the instantaneous LES flow fields in order to provide a statistical representation of the structures responsible for transition and their response to free-stream turbulence intensity and length scale.The presence of vortical filaments parallel to the wall,typically referred as boundary layer streaks,is clearly identified;their characteristic dimensions and how they change as a function of FSTI properties were analyzed within the paper.
文摘Objectives: The main steps for physiologic type reconstruction in 50 complicated corrosive strictures of upper alimentary tract are presented. Methods: In successive developed gastric outlet and esophageal strictures a limited Billroth I resection (in 9) or conversion a prior precolic GEA in such anastomosis (in 5) and middle or total gastrectomies (in 3) were performed. A second stage substernal by-pass with isoperistaltic transverse colon segment was done 6 - 12 weeks later. In all but one instances the graft was implanted high in the gastric stump. In extensive burned and retracted such lesion (in 3) a similar by-pass was carried out but the lower anastomosis was done with the not involved prepyloric segement. In concomittant antropyloric and esophageal strictures in 11 young, good risk patients, a limited Billroth I resction and simultaneous colonic bypass was used. In case of accompanied respiratory fistula (in 4) exclusion by-pass was useful for both lesions. The associated pyloric stricture (in 3) was solved at the same time. Side-to-end pharyngocolostomy was used in 4 high thoracocervical strictures. In 8 previously perforated strictures the by-ass was performed 2 months later. Reults: The overall mortality was 4%. The postoperative morbidity was low (8%). All cervical leaks closed spontaneously. Particular late complications required revisional surgery in 12, 5% of cases. Conclusion: In complicated corrosive strictures (esophageal, gastric, fistulas) limited Billoth I resection, isoperistaltic colon by-pass with high gastrocolic anastomosis, good gastric drainage and maintenance of the duodenum in gastrointestinal continuity are the main factors to achieve the best functional results.
文摘<em>Objective</em>: In order to take a decision about the revascularization approach to be adopted, it is of fundamental importance to determine whether coronary artery stenoses induce ischemia or not. An index, named (Fractional Flow Reserve), based on pressure measurements has been proposed to this aim and is usually interpreted in terms of flows. The objective of this work is to compute simultaneously pressures and flow rates in the coronary network of patients with three-vessel disease, in order to study more precisely the relationship between these two quantities. <em>Approach</em>: 22 patients have been included in the study. Some pressure and flow rate measurements were collected during by-pass surgery. These clinical data allow determining parameters for a patient’s specific model, based on the electric/hydraulic analogy. Collateral pathways are included in the model, as well as the severity of the disease and the impact of revascularization. <em>Main Results</em>: For patients with stenoses on LAD, LCx, LMCA and occlusion of the RCA, the flow rate delivered to the right territory is of course a function of the aortic pressure, the left stenoses severity, and the pressure distal to the thrombosis. But it mainly depends on the capillary and collateral resistances, and on the proportion between them. Abnormal microvascular hemodynamics, may be present in patients with non-hemodynamic significant lesions as assessed by the pressure ratio. Complete revascularization with the 3 grafts is demonstrated to be fully justified. The direction of collateral flows may be reversed, depending on the pressure gradient. In any case, they remain low and become negligible when the 3 grafts are operating. <em>Significance</em>: Surgical decision based only on pressure measurements may miss some real hemodynamic problems due to the considered stenosis. This risk is even greater in case of serial stenoses.
文摘Ventricular fibrillation seen just after declamping of the aorta is an undesirable condition causing myocardial injury. To return to normal rhythm, often internal shocks are applied. But defibrillation itself can also contribute to myocardial injury. So prevention of fibrillation is more important than treatment. 236 patients undergoing coronary artery by-pass surgery were included in this retrospective clinical study. 144 of those patients were operated using modified St. Thomas’ Hospital cardioplegic solution, for stopping the heart. In the other 92 patients, plegisol cardioplegic solution was used. We compared the two groups for the development of ventricular fibrilation after declamping of the aorta. In the modified St. Thomas’ Hospital group, ventricular fibrillation after declamping of the aorta was seen less frequently, this being statistically significant (22.2% vs. 52.2%, p = 0.026). This study shows that the modified St.Thomas’ Hospital cardioplegic solution is preferred for avoiding ventricular fibrillation occuring just after declamping of the aorta.
基金This work was financially supported by the National Basic Research Program of China(2019YFC1906900)Chinese Central Public Welfare Research Project(2019YSKY-016).
文摘Cement kiln co-processing techniques have been developed in the past 20 years in China,and more than 60 factories now use fermentation,screening,and gasification pre-treatment techniques to coprocess municipal solid waste(MSW).There three complete MSW pre-treatment techniques,coprocessing procedures,and environmental risk assessments have been described in few publications.In this study,we assessed the effectiveness of each technique.The results suggested that the pollutant content released by each pre-treatment technology was lower than the emission standard.To reveal the mechanisms of pollutant migration and enrichment,the substances in the kiln and kiln products are investigated.The input of co-processing materials(Co-M)produced by fermentation caused formation of polychlorinated dibenzo-p-dioxins and dibenzoftiran(PCDD/Fs)in the bypass flue gas(By-gas)in excess of the regulatory standard.The Co-M input produced by the screening and gasifier technologies caused the total organic carbon(TOC)concentration to exceed the standard.In addition,the NOx,TOC,and PCDD/Fs in the By-gas exceeded the regulatory standard.Raw meal was the primary chlorine and heavy metals input stream,and clinker(CK)and cement kiln dust(CKD)accounted for>90%of the total chlorine output stream.Flue gas and CKD were the primary volatile heavy metal(Hg)output streams.Greater than 70%of the semi-volatile heavy metals(Cd,Pb,T1 and Se)distributed in hot raw meal and bypass cement kiln dust.The low-volatility heavy metals were concentrated in the CK.These results indicated that co-processing techniques used in China still require improvement.