Separate treatment of high-nutrient sidestream is an efficient and cost effective way to decrease the loading on the main plant, resulting in lower effluent nutrient concentration. This study investigated the use of a...Separate treatment of high-nutrient sidestream is an efficient and cost effective way to decrease the loading on the main plant, resulting in lower effluent nutrient concentration. This study investigated the use of a combined forward osmosis-membrane distillation (FO-MD) system for the removal of nitrogen present in high concentration in sidestream from anaerobic digestion process. The combined system was able to achieve almost 100% rejection of solids and acetic acid, and more than 98% rejection of NH3-N from the sidestream. The high rejection of NH3-N was mainly achieved by the FO process. The solids in the feed solution contributed to fouling problem in both FO and MD, resulting in significant decline in flux. However, 76% or higher flux recovery was achieved for FO membrane by cleaning with tap water. We observed that flux recovery was due to removal of solids from the membrane surface by the cleaning process. FO membrane also demonstrated excellent performance for continuous operation when cleaned for 15 min in every 24 h interval. Overall, the combined FO-MD system was found to be an effective solution for treatment of nutrient rich sidestream.展开更多
Objective： Hemodilution changes the physical properties of blood by reducing its hematocrit and blood viscosity. We tested whether prolonged hypervolemic hemodilution （HHD） impairs functional capillary density （FC...Objective： Hemodilution changes the physical properties of blood by reducing its hematocrit and blood viscosity. We tested whether prolonged hypervolemic hemodilution （HHD） impairs functional capillary density （FCD） of ileal mucosa in healthy mechanically-ventilated pigs and if there is any correlation between changes in FCD of ileal and sublingual mucosas during HHD. Methods： Sixteen domestic female pigs were anesthetized, mechanically-ventilated, and randomly assigned to the HHD （20 ml/（kg.h） Hartmann＇s solution for 3 h） or fluid restrictive （5 ml/（kg-h） Hartmann＇s solution for 3 h） group. Microcirculations of sublingual and ileal mucosas via ileostomy were visualized using sidestream dark-field （SDF） imaging at baseline conditions （t=0 h） and at selected time intervals of fluid therapy （t=-l, 2, and 3 h）. Results： A significant decrease of ileal FCD （285 （278-292） cm/cm^2） in the HHD group was observed after the third hour of HHD when compared to the baseline （360 （350-370） cm/cm2） （P〈0.01）. This trend was not observed in the restrictive group, where the ileal mucosa FCD was significantly higher after the third hour of fluid therapy as compared to the HHD group （P〈0.01）. No correlation between microhemodynamic parameters obtained from sublingual and ileal mucosas was found throughout the study. Conclusions： Prolonged HHD established by crystalloid solution significantly decreased ileal villus FCD when compared to restrictive fluid regimen. An inappropriate degree of HHD can be harmful during uncomplicated abdominal surgery.展开更多
Background:This study aimed to compare sublingual microcirculatory parameters between anesthetized pigs and conscious adult humans using sidestream darkfield videomicroscopy.The overarching aim of the work was to vali...Background:This study aimed to compare sublingual microcirculatory parameters between anesthetized pigs and conscious adult humans using sidestream darkfield videomicroscopy.The overarching aim of the work was to validate the pig as an experimental model of changes in microcirculatory function following traumatic haemorrhagic shock and resuscitation.Methods:Fourteen large white pigs and 14 humans were recruited for the study.Sublingual sidestream darkfield videomicroscopy clips were captured in anesthetized pigs and conscious humans.Clips underwent manual analysis in Automated Vascular Analysis 3.2 software.The total vessel density(TVD),perfused vessel density(PVD),proportion of perfused vessels(PPVs)and microvascular flow index(MFI)were quantified.An independent samples t test was used for between species comparison of microcirculatory parameters.Results and Conclusions:Conscious humans had a significantly lower TVD,PVD and MFI than anesthetized pigs.No significant difference in PPVs was observed between the species.Perfusion of the microcirculation is a critical determinant of tissue metabolic function and viability.Whilst it may not be surprising that some inter species differences in the sublingual microcirculatory anatomy were identified between pig and human subjects,it is interesting to report the insignificant difference in PPVs.This direct microcirculatory measure represents a relative change which should hold translatable value across species.We therefore conclude the pig is a suitable model for microcirculatory research and may be a suitable species to investigate changes in microcirculatory perfusion following perturbations in cardiovascular homeostasis,for example during traumatic haemorrhagic shock and resuscitation.展开更多
目的探究脓毒症及感染性休克时舌下微循环与肠系膜微循环的关系，以及舌下、肠系膜微循环与整体血流动力学的关系。方法采用12头五指山近交系小型猪，随机分为对照组（n=6）和脓毒症组（n=6）。采用自体粪便注入腹腔方法制备腹膜炎脓毒...目的探究脓毒症及感染性休克时舌下微循环与肠系膜微循环的关系，以及舌下、肠系膜微循环与整体血流动力学的关系。方法采用12头五指山近交系小型猪，随机分为对照组（n=6）和脓毒症组（n=6）。采用自体粪便注入腹腔方法制备腹膜炎脓毒症模型。对照组仅做肠扰动。两组皆连续监测动脉血压、中心静脉压及每小时尿量。实验组猪模型制备完成后，分别于0、4、8、12h采用旁流暗视野技术（sidestream dark field imaging techniques，SDF）采集舌下及肠系膜微循环图像，猪休克后[平均动脉压（MAP）≤65mmHg]分别采集0、2、4h舌下及肠系膜微循环图像，微循环采用总血管密度（TVD）、灌注血管密度（PVD）、灌注血管比例（PPV）、微血管流动指数（MFI）作为观察指标，微循环指标由AVA3．0软件进行半定量分析。同时留取动脉血监测动脉血氧分压（PaO2）、二氧化碳分压（PaCO2）及血乳酸（Lac），相同时间点监测心率（HR）、平均动脉压（MAP）、心指数（CI）。结果①脓毒症模型制备8h后实验组猪舌下微循环和肠系膜微循环PPV和MFI与基线比较明显下降（〉30％，P〈0．05），实验组猪在出现感染性休克时舌下和肠系膜微循环PPV和MFI下降更为明显（〉50％，P〈0．05）。PVD较晚出现明显差异，舌下微循环和肠系膜微循环分别在制模12h及休克后0h出现；舌下微循环和肠系膜微循环TVD在整个实验过程中变化差异无统计学意义。②实验组猪舌下微循环和肠系膜微循环变化有明显的相关性（MFI：r=0．60，P〈0．01；TVD：r=0．284，P〈0．01；PVD：r=0．492，P〈0．01；PPV：r=0．705，P〈0．01）。③实验组猪休克前，CI与舌下微循环及肠系膜微循环PPV、MFI均存在相关性。休克后CI与舌下微循环及肠系膜微循环各指标均无相关性。休克前后舌下微循环及肠系膜微循环与MAP均无相关性。在脓毒症模型制备后12h，MAP〉100mmHg，舌下微循环及肠系膜微循环PPV、MFI均在模型制备后8h出现明显下降。微循环改变发生在MAP下降之前。结论①脓毒症及感染性休克猪存在微循环改变，且在感染性休克时微循环障碍更严重；②舌下微循环与肠系膜微循环存在相关性，可以通过SDF技术监测舌下微循环间接反映脏器微循环的变化；③微循环的改变发生在MAP下降之前。展开更多
文摘Separate treatment of high-nutrient sidestream is an efficient and cost effective way to decrease the loading on the main plant, resulting in lower effluent nutrient concentration. This study investigated the use of a combined forward osmosis-membrane distillation (FO-MD) system for the removal of nitrogen present in high concentration in sidestream from anaerobic digestion process. The combined system was able to achieve almost 100% rejection of solids and acetic acid, and more than 98% rejection of NH3-N from the sidestream. The high rejection of NH3-N was mainly achieved by the FO process. The solids in the feed solution contributed to fouling problem in both FO and MD, resulting in significant decline in flux. However, 76% or higher flux recovery was achieved for FO membrane by cleaning with tap water. We observed that flux recovery was due to removal of solids from the membrane surface by the cleaning process. FO membrane also demonstrated excellent performance for continuous operation when cleaned for 15 min in every 24 h interval. Overall, the combined FO-MD system was found to be an effective solution for treatment of nutrient rich sidestream.
基金Project (No. MZO 00179906) supported by the Ministry of Health,Czech Republic
文摘Objective： Hemodilution changes the physical properties of blood by reducing its hematocrit and blood viscosity. We tested whether prolonged hypervolemic hemodilution （HHD） impairs functional capillary density （FCD） of ileal mucosa in healthy mechanically-ventilated pigs and if there is any correlation between changes in FCD of ileal and sublingual mucosas during HHD. Methods： Sixteen domestic female pigs were anesthetized, mechanically-ventilated, and randomly assigned to the HHD （20 ml/（kg.h） Hartmann＇s solution for 3 h） or fluid restrictive （5 ml/（kg-h） Hartmann＇s solution for 3 h） group. Microcirculations of sublingual and ileal mucosas via ileostomy were visualized using sidestream dark-field （SDF） imaging at baseline conditions （t=0 h） and at selected time intervals of fluid therapy （t=-l, 2, and 3 h）. Results： A significant decrease of ileal FCD （285 （278-292） cm/cm^2） in the HHD group was observed after the third hour of HHD when compared to the baseline （360 （350-370） cm/cm2） （P〈0.01）. This trend was not observed in the restrictive group, where the ileal mucosa FCD was significantly higher after the third hour of fluid therapy as compared to the HHD group （P〈0.01）. No correlation between microhemodynamic parameters obtained from sublingual and ileal mucosas was found throughout the study. Conclusions： Prolonged HHD established by crystalloid solution significantly decreased ileal villus FCD when compared to restrictive fluid regimen. An inappropriate degree of HHD can be harmful during uncomplicated abdominal surgery.
基金UQ Midwinter Group funds.RL received PhD candidature funding from the Australian Government Research Training Program.
文摘Background:This study aimed to compare sublingual microcirculatory parameters between anesthetized pigs and conscious adult humans using sidestream darkfield videomicroscopy.The overarching aim of the work was to validate the pig as an experimental model of changes in microcirculatory function following traumatic haemorrhagic shock and resuscitation.Methods:Fourteen large white pigs and 14 humans were recruited for the study.Sublingual sidestream darkfield videomicroscopy clips were captured in anesthetized pigs and conscious humans.Clips underwent manual analysis in Automated Vascular Analysis 3.2 software.The total vessel density(TVD),perfused vessel density(PVD),proportion of perfused vessels(PPVs)and microvascular flow index(MFI)were quantified.An independent samples t test was used for between species comparison of microcirculatory parameters.Results and Conclusions:Conscious humans had a significantly lower TVD,PVD and MFI than anesthetized pigs.No significant difference in PPVs was observed between the species.Perfusion of the microcirculation is a critical determinant of tissue metabolic function and viability.Whilst it may not be surprising that some inter species differences in the sublingual microcirculatory anatomy were identified between pig and human subjects,it is interesting to report the insignificant difference in PPVs.This direct microcirculatory measure represents a relative change which should hold translatable value across species.We therefore conclude the pig is a suitable model for microcirculatory research and may be a suitable species to investigate changes in microcirculatory perfusion following perturbations in cardiovascular homeostasis,for example during traumatic haemorrhagic shock and resuscitation.
文摘目的探究脓毒症及感染性休克时舌下微循环与肠系膜微循环的关系，以及舌下、肠系膜微循环与整体血流动力学的关系。方法采用12头五指山近交系小型猪，随机分为对照组（n=6）和脓毒症组（n=6）。采用自体粪便注入腹腔方法制备腹膜炎脓毒症模型。对照组仅做肠扰动。两组皆连续监测动脉血压、中心静脉压及每小时尿量。实验组猪模型制备完成后，分别于0、4、8、12h采用旁流暗视野技术（sidestream dark field imaging techniques，SDF）采集舌下及肠系膜微循环图像，猪休克后[平均动脉压（MAP）≤65mmHg]分别采集0、2、4h舌下及肠系膜微循环图像，微循环采用总血管密度（TVD）、灌注血管密度（PVD）、灌注血管比例（PPV）、微血管流动指数（MFI）作为观察指标，微循环指标由AVA3．0软件进行半定量分析。同时留取动脉血监测动脉血氧分压（PaO2）、二氧化碳分压（PaCO2）及血乳酸（Lac），相同时间点监测心率（HR）、平均动脉压（MAP）、心指数（CI）。结果①脓毒症模型制备8h后实验组猪舌下微循环和肠系膜微循环PPV和MFI与基线比较明显下降（〉30％，P〈0．05），实验组猪在出现感染性休克时舌下和肠系膜微循环PPV和MFI下降更为明显（〉50％，P〈0．05）。PVD较晚出现明显差异，舌下微循环和肠系膜微循环分别在制模12h及休克后0h出现；舌下微循环和肠系膜微循环TVD在整个实验过程中变化差异无统计学意义。②实验组猪舌下微循环和肠系膜微循环变化有明显的相关性（MFI：r=0．60，P〈0．01；TVD：r=0．284，P〈0．01；PVD：r=0．492，P〈0．01；PPV：r=0．705，P〈0．01）。③实验组猪休克前，CI与舌下微循环及肠系膜微循环PPV、MFI均存在相关性。休克后CI与舌下微循环及肠系膜微循环各指标均无相关性。休克前后舌下微循环及肠系膜微循环与MAP均无相关性。在脓毒症模型制备后12h，MAP〉100mmHg，舌下微循环及肠系膜微循环PPV、MFI均在模型制备后8h出现明显下降。微循环改变发生在MAP下降之前。结论①脓毒症及感染性休克猪存在微循环改变，且在感染性休克时微循环障碍更严重；②舌下微循环与肠系膜微循环存在相关性，可以通过SDF技术监测舌下微循环间接反映脏器微循环的变化；③微循环的改变发生在MAP下降之前。
