Performance evaluation of micro-aerobic hydrolysis of mixed sludge: Optimum aeration and effect on its biochemical methane potential.

This study evaluated the performance of a micro-aerobic hydrolysis of mixed sludge and its influence as a pretreatment of this waste for its subsequent anaerobic digestion. Three experimental series were carried out to evaluate the optimum micro-aeration levels in the range from 0.1 to 0.5 air volume/min.reactor volume (vvm) and operation times within the range of 24-60 h. The maximum methane yield [35 mL CH4/g volatile suspended solids (VSS) added] was obtained for an aeration level of 0.35 vvm. This methane yield value increased 114% with respect to that obtained with the non-aerated sludge. In the micro-aeration process carried out at an aeration level of 0.35 vvm, increases in soluble proteins and total sugars concentrations of 185% and 192% with respect to their initial values were found, respectively, after 48 h of aeration. At the above micro-aerobic conditions, soluble chemical oxygen demand (CODS) augmented 150%, whereas VSS content decreased until 40% of their initial respective values. Higher COD increases and VSS decreases were found at 60 h of micro-aeration, but the above parameters did not vary significantly with respect to the values found at 48 h.

Value of second-trimester uterine artery pulsatility index in pregnancies with systemic lupus erythematosus and/or antiphospholipid syndrome.

OBJECTIVE: To assess the value of the second trimester mean pulsatility index of the uterine arteries (MPI-UtA) to predict adverse perinatal outcome (APO) in women with systemic lupus erythematosus (SLE) and/or antiphospholipid syndrome (APS). METHODS: Pregnancies with either an SLE diagnosis or with primary APS controlled at our Hospital during a 10 years period were included. MPI-UtA was performed between 19-23 weeks' gestation. The MPI-UtA was defined as abnormal when it was >95th centile. APO was defined as the presence of: preeclampsia (PE), small for gestational age (SGA) newborn, preterm delivery, placental abruption and fetal or neonatal death. RESULTS: There were 39 ongoing pregnancies, 16 of them with SLE and 23 with primary APS. Nine patients had no previous pregnancy (23%). Globally, 35 live births were recorded, being the mean gestational age at delivery 38.1 ± 2.1 weeks and the mean birth weight 2835 ± 492 g. Abnormal MPI-UtA was found in 6 (15%) pregnancies, all of them (100%) had an APO: there were 4 fetal deaths and 2 further severe PE with live newborn. Normal MPI-UtA was shown in the remaining 33 (84.6%); of them, 6 (18%) had an APO: one late PE with a premature newborn, another one severe preterm baby and 4 SGA term newborns. No cases of perinatal death occurred in this group. Therefore, accuracy of MPI-UtA evaluation for APO was: sensitivity 50%, specificity 100%, PPV 100% and NPV 82%, respectively (p < .001). CONCLUSION: Abnormal second-trimester uterine artery Doppler evaluation is highly predictive for adverse perinatal outcome in pregnancies affected by SLE or APS.

Induction of labour as compared with spontaneous labour in low-risk women: A multicenter study in Catalonia.

OBJECTIVE: To compare birth and neonatal outcomes in low-risk women undergoing induced labour with those undergoing spontaneous onset. METHODS: This retrospective multicentre study included 30 public maternity hospitals in Catalonia between 2016 and 2017. The study population consisted of 5,717 women. RESULTS: Of the 5,717 births, 75.8% had spontaneous onset and 24.2% had an induction. Induced labour was more likely at week 41 of gestation and in nulliparous women. Induced labour increased the likelihood of undergoing caesarean section (adjusted OR [ORa], 2.59; 95% confidence interval [CI], 2.11-3.16), assisted vaginal birth (ORa, 1.70; 95% CI, 1.46-1.98), epidural analgesia (ORa, 2.64; CI, 2.14-3.27), postpartum haemorrhage (ORa, 1.56; 95% CI, 1.14-2.15) and episiotomy (ORa, 1.26; 95% CI, 1.08-1.47). Induced labour was also associated with not performing skin-to-skin contact with the mother (ORa, 0.47; 95% CI, 0.39-0.58) and with not performing early breastfeeding (ORa, 0.49; 95% CI, 0.39-0.61). CONCLUSIONS: The frequency of labour inductions among low-risk women exceeds the level recommended by scientific organisations in Catalonia and Spain, and is associated with adverse birth outcomes such as increased caesarean section rates, assisted vaginal births, and episiotomy rates. It is also associated with the failure to perform early skin-to-skin contact with the mother and failure to initiate early breastfeeding.

Oxytocin Administration in Low-Risk Women, a Retrospective Analysis of Birth and Neonatal Outcomes.

BACKGROUND: In recent years, higher than the recommended rate of oxytocin use has been observed among low-risk women. This study examines the relationship between oxytocin administration and birth outcomes in women and neonates. METHODS: A retrospective analysis of birth and neonatal outcomes for women who received oxytocin versus those who did not. The sample included 322 women with a low-risk pregnancy. RESULTS: Oxytocin administration was associated with cesarean section (aOR 4.81, 95% CI: 1.80-12.81), instrumental birth (aOR 3.34, 95% CI: 1.45-7.67), episiotomy (aOR 3.79, 95% CI: 2.20-6.52) and length of the second stage (aOR 00:18, 95% CI: 00:04-00:31). In neonatal outcomes, oxytocin in labor was associated with umbilical artery pH ≤ 7.20 (OR 3.29, 95% CI: 1.33-8.14). Admission to neonatal intensive care unit (OR 0.56, 95% CI: 0.22-1.42), neonatal resuscitation (OR 1.04, 95% CI: 0.22-1.42), and Apgar score <7 (OR 0.48, 95% CI: 0.17-1.33) were not associated with oxytocin administration during labor. CONCLUSIONS: Oxytocin administration during labor for low-risk women may lead to worse birth outcomes with an increased risk of instrumental birth and cesarean, episiotomy and the use of epidural analgesia for pain relief. Neonatal results may be also worse with an increased proportion of neonates displaying an umbilical arterial pH ≤ 7.20.

Middle cerebral artery Doppler pulsatility index as a predictor of intrapartum meconium release in prolonged pregnancies.

OBJECTIVES: The aim of this study was to asses the correlation of middle cerebral artery pulsatility index (MCA-PI) and perinatal outcomes in prolonged pregnancies. STUDY DESIGN: This was a prospective study of all consecutive pregnant women beyond 41 weeks' gestation attending for obstetric surveillance during a two years period. We evaluated the predictive value of MCA-PI lower than the 5th percentile (

Improvement of methane content in a hydrogenotrophic anaerobic digester via the proper operation of membrane module integrated into an external-loop.

This work assessed the feasibility of a hydrogenotrophic biogas process integrated with a membrane module in the external-loop design. The major scope was to conduct the investigation from the perspective of the membrane unit and reveal how the operating strategy influences the efficiency of biogas formation. It was observed that the fermenter worked with an improved efficacy, indicated by the higher concentration of methane in the headspace (80-90%) when the gas loading intensity, defined as the ratio of inlet gas permeation rate and the circulation rate of the liquid phase, was adjusted to lower values (3-5.3×10-3). Such results are implying that the mass transfer of H2 into the reactor is dependent on this critical parameter. Moreover, attention should be paid to the fouling of the module under longer-term experiments to keep its performance at a sufficient level.