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41.
Reza Barati rashvanlou Abbas Rezaee Mahdi Farzadkia Mitra Gholami Majid Kermani 《RSC advances》2020,10(59):35718
Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. 相似文献
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Shazli Azmi Maryam Ferdousi Ioannis N. Petropoulos Georgios Ponirakis Uazman Alam Hassan Fadavi Omar Asghar Andrew Marshall Andrew J. Atkinson Wendy Jones Andrew J.M. Boulton Mitra Tavakoli Maria Jeziorska Rayaz A. Malik 《Diabetes care》2015,38(8):1502-1508
OBJECTIVEImpaired glucose tolerance (IGT) through to type 2 diabetes is thought to confer a continuum of risk for neuropathy. Identification of subjects at high risk of developing type 2 diabetes and, hence, worsening neuropathy would allow identification and risk stratification for more aggressive management.RESULTSTen subjects who developed type 2 diabetes had a significantly lower CNFD (P = 0.003), CNBD (P = 0.04), and CNFL (P = 0.04) compared with control subjects at baseline and a further reduction in CNFL (P = 0.006), intraepidermal nerve fiber density (IENFD) (P = 0.02), and mean dendritic length (MDL) (P = 0.02) over 3 years. Fifteen subjects who remained IGT and 5 subjects who returned to normal glucose tolerance had no significant baseline abnormality on CCM or IENFD but had a lower MDL (P < 0.0001) compared with control subjects. The IGT subjects showed a significant decrease in IENFD (P = 0.02) but no change in MDL or CCM over 3 years. Those who returned to NGT showed an increase in CNFD (P = 0.05), CNBD (P = 0.04), and CNFL (P = 0.05), but a decrease in IENFD (P = 0.02), over 3 years.CONCLUSIONSCCM and skin biopsy detect a small-fiber neuropathy in subjects with IGT who develop type 2 diabetes and also show a dynamic worsening or improvement in corneal and intraepidermal nerve morphology in relation to change in glucose tolerance status. 相似文献
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There are few good biomarkers of iron deficiency anemia (IDA). Since IDA patients have evidence for increased oxidative stress, we used mass spectrometry (MS) [i.e. matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization] to identify novel biomarkers. Using MALDI-MS, the following oxidative modifications of hemoglobin with the following mass-to-charge ratios were identified: 1,087.5 (α32-40), 1,545.7 (α17-31), 1,290.0 (β31-40) and 2,076.1 (β41-59). On electrospray ionization MS, the IDA patients had significantly elevated glutathionyl hemoglobin (GSHb) compared with the controls (16.9 ± 9.6 vs. 7.7 ± 3.7%; p = 0.002). GSHb levels correlated inversely with serum ferritin (Spearman rho -0.485; p = 0.003) and positively with serum transferrin receptor (0.460; p = 0.002). GSHb also demonstrated inverse correlations with hemoglobin (-0.512; p = 0.001), mean cell volume (-0.419; p = 0.026), serum iron (-0.446; p = 0.008) and transferrin saturation (-0.460; p = 0.008). For the first time, we show that GSHb is elevated in patients with IDA and has potential as a biomarker of this form of anemia. 相似文献
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Objective. To determine intrafamilial seropositivity of HBV and HCV and to compare them in families of infected persons with HBV and HCV in Hamadan clinic of hepatitis.Material and methods. In this analytic cross-sectional study, 651 family members of 200 HBV and HCV infection index cases were entered into the study and after signing an informed consent, they were referred to Blood Transfusion Center. With completion of laboratory tests, interviewers filled the questionnaires.Results. One hundred and eighteen (20.5%) and 107 (18.6%) family members were HBsAg and HBcAb positive respectively. 21 (3.6%) were isolated HBcAb positive. Only one person (1.3%) was HCVAb positive. The general rate of infection in family members of HBV infected people (atleast one case) (49.4%) was significantly higher than that of HCV infected people (3.3%), p < 0.001. Interspouses transmission was evaluated and prevalence of interspouses HBV and HCV infection were 32.3 and 8%, respectively.Conclusion. Intrafamilial and interspousal seropositivity of HBV is obviously more than those of HCV. More attention should be paid to screening and risk lowering activities particularly about HBV infected people and their families. 相似文献
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Herein we developed a rapid, cheap, and water-soluble ultra-sensitive ZnO quantum dot (QD) based metal sensor for detecting different hazardous metal ions up to the picomolar range in water. Various spectroscopic and microscopic techniques confirmed the formation of 2.15 ± 0.46 μm of ZnO QD conjugated CMC microspheres (ZCM microspheres) which contain 5.5 ± 0.5 nm fluorescent zinc oxide (ZnO) QDs. Our system, as a promising sensor, exhibited excellent photostability and affinity towards various heavy metal ions. The detection limits were calculated to be 16 pM for Cu2+ and 0.18 nM for Cr6+ ions which are better than previously reported values. The simple fluorescence ‘turn off’ property of our ZCM microsphere sensor system can serve a two-in-one purpose by not only detecting the heavy metals but also quantifying them. Nonetheless, pattern recognition for different heavy metals helped us to detect and identify multiple heavy metal ions. Finally, their practical applications on real samples also demonstrated that the ZCM sensor can be effectively utilized for detection of Cr6+, Fe3+, Cu2+ present in the real water samples. This study may inspire future research and design of target fluorescent metal oxide QDs with specific functions.Herein we developed a rapid, cheap, and water-soluble ultra-sensitive ZnO quantum dot (QD) based metal sensor for detecting different hazardous metal ions up to the picomolar range in water. 相似文献
50.
Asim Kumar Manna Aparajita Samaddar Sumit Mitra Swapan Pathak Srabani Chakrabarti Diptendra Kumar Sarkar 《The Indian journal of surgery》2013,75(3):204-209
Breast carcinoma is the most common cause of carcinoma death in women. Sometimes, difficulty arises to differentiate between premalignant lesions and carcinoma by routine histopathology. Our study was done to establish the role of morphometry and immunohistochemistry to solve this problem. In this study, total 60 cases of different breast lesions were included and 10 controls were also included to compare the results with the normal findings. They were studied by hematoxylin and eosin-stained sections for morphometry and routine histological study; as well as by proliferative markers such as proliferating cell nuclear antigen and p53. Invasiveness was studied using immunohistochemical staining with 34 βE12 monoclonal antibody. Statistically significant differences were found in morphometric parameters and in expression of proliferative markers between most of them. Morphometry and immunohistochemistry help in the proper diagnosis of different breast lesions that lie in the gray zone on routine histopathology. 相似文献