Use of N-Methylmorpholine N-oxide (NMMO) pretreatment to enhance the bioconversion of lignocellulosic residues to methane.

Lignocellulosic residues (LRs) are one of the most abundant wastes produced worldwide. Nevertheless, unlocking the full energy potential from LRs for biofuel production is limited by their complex structure. This study investigated the effect of N-methylmorpholine N-oxide (NMMO) pretreatment on almond shell (AS), spent coffee grounds (SCG), and hazelnut skin (HS) to improve their bioconversion to methane. The pretreatment was performed using a 73% NMMO solution heated at 120 °C for 1, 3, and 5 h. The baseline methane productions achieved from raw AS, SCG, and HS were 54.7 (± 5.3), 337.4 (± 16.5), and 265.4 (± 10.4) mL CH4/g VS, respectively. The NMMO pretreatment enhanced the methane potential of AS up to 58%, although no changes in chemical composition and external surface were observed after pretreatment. Opposite to this, pretreated SCG showed increased porosity (up to 63%) and a higher sugar percentage (up to 27%) after pretreatment despite failing to increase methane production. All pretreatment conditions were effective on HS, achieving the highest methane production of 400.4 (± 9.5) mL CH4/g VS after 5 h pretreatment. The enhanced methane production was due to the increased sugar percentage (up to 112%), lignin removal (up to 29%), and loss of inhibitory compounds during the pretreatment. An energy assessment revealed that the NMMO pretreatment is an attractive technology to be implemented on an industrial scale for energy recovery from HS residues. Supplementary Information: The online version contains supplementary material available at 10.1007/s13399-022-03173-x.

Which clinical factors delay proper treatment in panic disorder? A cross-sectional multicentric study.

AIM: The aim of the present study was to identify clinical and socio-demographic factors associated with duration of untreated illness (DUI) in patients affected by panic disorder (PD). METHODS: Data were collected from patients' medical records (N = 157) of two mental health services respectively located in Milan and in Monza (Italy). Correlation analyses and analysis of variance (ANOVAs) were run to analyse the relation between DUI and quantitative/qualitative variables respectively. Statistically significant variables in uni- variate analyses were then inserted in a linear multivariable regression model (backward procedure). RESULTS: Mean DUI was 27.33 (±50.56) months. Patients with an earlier age at onset (r = -0.270; p < .01), a longer duration of illness (r = 0.483; p < .01) and who received a lifetime psychotherapy (F = 6.86; p = .01) had a longer DUI. The final global model showed that a longer DUI was associated with pre-onset poly-substance misuse (p = .05) and a longer duration of illness (p < .01). CONCLUSION: The results of our study showed that a longer DUI was predicted by clinical factors such as the presence of a pre-onset poly-substance use disorder and that delayed proper treatment can lead to a chronicization of PD, as indicated by a longer duration of illness. Further studies are needed to in-depth investigate the role of DUI in influencing the course and outcome of anxiety disorders, including PD.

Long-term urological outcome of cloaca patients with multidisciplinary management.

PURPOSE: Urological management of Cloacal Malformation (CM) focuses on preserving renal function and continence. Study aim was to analyze urinary and intestinal outcomes in CM patients, considering the length of common channel (CC) and presence of occult spinal dysraphism (OSD). METHODS: Retrospective review of CM treated at our institution by a multidisciplinary team from 1999 to 2020. Patients with follow-up < 2.5 years were excluded. Length of CC, renal function, urinary and bowel outcomes, presence of associated anomalies (especially OSD) were evaluated. RESULTS: Twenty patients were included, median age at follow-up: 8 years (4-15). A long CC > 3 cm was described in 11 (55%). Chronic kidney disease was found in 3 patients. Urinary continence was achieved in 8/20 patients, dryness (with intermittent catheterization) in 9/20. Fecal continence was obtained in 3/20, cleanliness in 14 (under bowel regimen). OSD was present in 10 patients (higher prevalence in long-CC, 73%). Among OSD, 1 patient reached fecal continence, 7 were clean; 2 achieved urinary continence, while 6 were dry. CONCLUSIONS: Length of CC and OSD may affect urinary and fecal continence. An early counseling can improve outcome at long-term follow-up. Multidisciplinary management with patient centralization in high grade institutions is recommended to achieve better results.

Inventory of landslides triggered by an extreme rainfall event in Marche-Umbria, Italy, on 15 September 2022.

Systematic and timely documentation of triggered (i.e. event) landslides is fundamental to build extensive datasets worldwide that may help define and/or validate trends in response to climate change. More in general, preparation of landslide inventories is a crucial activity since it provides the basic data for any subsequent analysis. In this work we present an event landslide inventory map (E-LIM) that was prepared through a systematic reconnaissance field survey in about 1 month after an extreme rainfall event hit an area of about 5000 km2 in the Marche-Umbria regions (central Italy). The inventory reports evidence of 1687 triggered landslides in an area of ~550 km2. All slope failures were classified according to type of movement and involved material, and documented with field pictures, wherever possible. The database of the inventory described in this paper as well as the collection of selected field pictures associated with each feature is publicly available at figshare.

Radio-iodine refractory thyroid cancer patients: a tailored follow-up based on clinicopathological features.

OBJECTIVE: To report the experience of a single center for the selection of radioiodine-refractory (RAIR) thyroid cancer patients (RAIR-TC) who needed tyrosine kinase inhibitor (TKIs) treatment. PATIENTS AND METHODS: We evaluated all features of 279 RAIR-TC patients both at the time of diagnosis and at the RAIR diagnosis. RESULTS: Ninety-nine patients received indication to TKIs (Group A), while 180 remained under active surveillance (Group B). Group A had greater tumor size, more aggressive histotype, more frequent macroscopic extrathyroidal extension, distant metastases, advanced AJCC stage, and higher ATA risk of recurrence. After RAIR diagnosis, 93.9% of Group A had progression of disease (PD) after which TKIs' therapy was started. The remaining 6.1% of patients had a so severe disease at the time of RAIR diagnosis that TKIs' therapy was immediately started. Among Group B, 42.7% had up to 5 PD, but the majority underwent local treatments. The mean time from RAIR diagnosis to the first PD was shorter in Group A, and the evidence of PD within 25 months from RAIR diagnosis was associated with the decision to start TKIs. CONCLUSIONS: According to our results, a more tailored follow-up should be applied to RAIR-TC patients. A too strict monitoring and too many imaging evaluations might be avoided in those with less-aggressive features and low rate of progression. Conversely, RAIR-TC with an advanced stage at diagnosis and a first PD occurring within 25 months from RAIR diagnosis would require a more stringent follow-up to avoid a late start of TKIs.

Time course of ischemic and bleeding burden in consecutive patients undergoing transcatheter aortic valve replacement (FOCUS-ONE Registry).

BACKGROUND AND AIMS: Ischemic or bleeding events might occur after transcatheter aortic valve replacement (TAVR), with the potential to hamper clinical outcomes. This study aimed to characterize the average daily ischemic risks (ADIRs) and the average daily bleeding risks (ADBRs) over 1-year in all consecutive patients undergoing TAVR. METHODS: ADBR included all bleeding events according to VARC-2 definition, and ADIR included cardiovascular deaths, myocardial infarction and ischemic stroke. ADIRs and ADBRs were assessed within different timeframes post TAVR: acute (0-30 days), late (31-180 days), and very late (>181 days). Generalized estimating equations were used to test the least squares mean differences for the pairwise comparison of ADIRs and ADBRs. Our analysis was performed in the overall cohort and according to antithrombotic strategy (LT-OAC vs No LT-OAC). RESULTS: Ischemic burden was higher than bleeding burden, independently from the indication to LT-OAC, and in all timeframes examined. In the overall population, ADIRs were three-fold ADBRs (0.0467 [95% CI, 0.0431-0.0506] vs 0.0179 [95% CI, 0.0174-0.0185]; p < 0.001*). While ADIR was significantly higher in the acute phase, ADBR was relatively stable in all timeframes analysed. Of note, in LT-OAC population, OAC + SAPT group showed lower ischemic risk and higher bleeding events compared with OAC alone (ADIR: 0.0447 [95% CI: 0.0417-0.0477] vs 0.0642 [95% CI: 0.0557-0.0728]; p < 0.001*, ADBR 0.0395 [95% CI: 0.0381-0.0409] vs 0.0147 [95% CI: 0.0138-0.0156]; p < 0.001*). CONCLUSIONS: In patients undergoing TAVR Average daily risk fluctuates over time. However, ADIRs overcome ADBRs in all timeframes, especially in the acute phase and regardless of antithrombotic strategy adopted.

Low dose rate γ-irradiation protects fruit fly chromosomes from double strand breaks and telomere fusions by reducing the esi-RNA biogenesis factor Loquacious.

It is still continuously debated whether the low-dose/dose-rate (LDR) of ionizing radiation represents a hazard for humans. Model organisms, such as fruit flies, are considered valuable systems to reveal insights into this issue. We found that, in wild-type Drosophila melanogaster larval neuroblasts, the frequency of Chromosome Breaks (CBs), induced by acute γ-irradiation, is considerably reduced when flies are previously exposed to a protracted dose of 0.4 Gy delivered at a dose rate of 2.5 mGy/h. This indicates that this exposure, which is associated with an increased expression of DNA damage response proteins, induces a radioadaptive response (RAR) that protects Drosophila from extensive DNA damage. Interestingly, the same exposure reduces the frequency of telomere fusions (TFs) from Drosophila telomere capping mutants suggesting that the LDR can generally promote a protective response on chromatin sites that are recognized as DNA breaks. Deep RNA sequencing revealed that RAR is associated with a reduced expression of Loquacious D (Loqs-RD) gene that encodes a well-conserved dsRNA binding protein required for esiRNAs biogenesis. Remarkably, loss of Loqs mimics the LDR-mediated chromosome protection as it decreases the IR-induced CBs and TFs frequency. Thus, our molecular characterization of RAR identifies Loqs as a key factor in the cellular response to LDR and in the epigenetic routes involved in radioresistance.

Ultrasounds application for nut and coffee wastes valorisation via biomolecules solubilisation and methane production.

Lignocellulosic materials (LMs) are abundant feedstocks with excellent potential for biofuels and biocommodities production. In particular, nut and coffee wastes are rich in biomolecules, e.g. sugars and polyphenols, the valorisation of which still has to be fully disclosed. This study investigated the effectiveness of ultrasounds coupled with hydrothermal (i.e. ambient temperature vs 80 °C) and methanol (MeOH)-based pretreatments for polyphenols and sugar solubilisation from hazelnut skin (HS), almond shell (AS), and spent coffee grounds (SCG). The liquid fraction obtained from the pretreated HS was the most promising in terms of biomolecules solubilisation. The highest polyphenols, i.e. 123.9 (±2.3) mg/g TS, and sugar, i.e. 146.0 (±3.4) mg/g TS, solubilisation was obtained using the MeOH-based medium. However, the MeOH-based media were not suitable for direct anaerobic digestion (AD) due to the MeOH inhibition during AD. The water-based liquors obtained from pretreated AS and SCG exhibited a higher methane potential, i.e. 434.2 (±25.1) and 685.5 (±39.5) mL CH4/g glucosein, respectively, than the HS liquors despite having a lower sugar concentration. The solid residues recovered after ultrasounds pretreatment were used as substrates for AD as well. Regardless the pretreatment condition, the methane potential of the ultrasounds pretreated HS, AS, and SCG was not improved, achieving maximally 255.4 (±7.4), 42.8 (±3.3), and 366.2 (±4.2) mL CH4/g VS, respectively. Hence, the solid and liquid fractions obtained from HS, AS, and SCG showed great potential either as substrates for AD or, in perspective, for biomolecules recovery in a biorefinery context.

Mathematical modelling of an intermittent anoxic/aerobic MBBR: Estimation of nitrification rates and energy savings.

This study aimed at modelling the performance of a novel MBBR configuration, named A/O-MBBR, comprised of a pre-anoxic reactor, with an HRT of 4.5 h, coupled with an intermittent anoxic/aerobic MBBR (HRT = 6.8 h). The lab-scale system was fed with municipal wastewater with an average influent Total Ammonia Nitrogen (TAN) and total COD (TCOD) concentrations of 46 mg of TAN-N L-1 and 310 mg TCOD L-1. During the whole experimental period, TAN removal efficiency was always higher than 96%; denitrification was also very effective, achieving nitrate and nitrite concentrations in the effluent both lower than 5 mg NOx-N L-1 on average. Moreover, TCOD average removal efficiency was equal to 85%. Modelling was performed to investigate the nitrification efficacy enhancement; to this aim, a biofilm model was developed, adopting the equations for mixed-culture biofilms and the Activated Model Sludge n°1 (ASM1) for the biological processes rates. The model allowed to determine the maximum uptake rate for autotrophic growth (µA was 2.5 d-1) and the semisaturation constant (KOA was 0.2 mg O2 L-1), suggesting that the nitrification process was 3-fold faster than average and very effective at low oxygen concentrations. The model estimated that about 85% of TAN was removed by the biofilm and only the remaining part by suspended biomass in the bulk liquid. Finally, it was assessed that the A/O-MBBR configuration allowed for a 45-60% savings of the energy requirement compared to a Benchmark WWTP layout.

A cross-cultural comparison of sleep patterns between typically developing children and children with ASD living in Saudi Arabia and the United Kingdom.

BACKGROUND: Sleep is crucial for child development, especially for children with ASD. While it is known that children with ASD experience more severe sleep problems and that these problems tend to persist compared to their typically developing counterparts, these findings tend to come from only Western countries. A cross-cultural study is important to understand if the prevailing understanding of sleep in children with ASD can be extended to different cultural backgrounds. AIM: A cross-cultural study is conducted, involving typically developing children and children with ASD aged 5-12 across two countries: Saudi Arabia and the United Kingdom. METHODS AND PROCEDURES: Using a combination of questionnaires measuring ASD severity (CARS-2), sleep quality (CSHQ), sociodemographic and lifestyle variables and sleep diaries, 244 children were sampled using a mixture of snowball and convenience sampling methods. OUTCOMES AND RESULTS: Children with ASD experience more sleep problems compared to typically developing children in Saudi Arabia, and these problems similarly persist across time. Specifically, it was found that children with ASD in Saudi Arabia experience greater sleep onset latency and a greater number of night awakenings. Additionally, across the ASD groups, it was found that children from Saudi Arabia generally experienced poorer sleep than children in the United Kingdom in terms of shorter sleep duration, although children in the United Kingdom tended to report more instances of sleep anxiety and parasomnias. CONCLUSIONS AND IMPLICATIONS: Several reasons such as parental education about sleep hygiene, cultural influences and social hours were put forward as potential explanations for cross-cultural differences. Findings served to emphasise the importance of culturally-appropriate interventions and public education regarding child sleep.

Immediate versus staged revascularisation of non-culprit arteries in patients with acute coronary syndrome: a systematic review and meta-analysis.

Although there is robust evidence that revascularisation of non-culprit vessels should be pursued in patients presenting with an acute coronary syndrome (ACS) and multivessel coronary artery disease (MVD), the optimal timing of complete revascularisation remains disputed. In this systematic review and meta-analysis our results suggest that outcomes are comparable for immediate and staged complete revascularisation in patients with ACS and MVD. However, evidence from randomised controlled trials remains scarce and cautious interpretation of these results is recommended. More non-biased evidence is necessary to aid future decision making on the optimal timing of complete revascularisation.

Fed-batch anaerobic digestion of raw and pretreated hazelnut skin over long-term operation.

This study provided important insights on the anaerobic digestion (AD) of hazelnut skin (HS) by operating a fed-batch AD reactor over 240 days and focusing on several factors impacting the process in the long term. An efficient reactor configuration was proposed to increase the substrate load while reducing the solid retention time during the fed-batch AD of HS. Raw HS produced maximally 19.29 mL CH4/g VSadd/d. Polyphenols accumulated in the reactor and the use of NaOH to adjust the pH likely inhibited AD. Maceration and methanol-organosolv pretreatments were, thus, used to remove polyphenols from HS (i.e. 82 and 97%, respectively) and improve HS biodegradation. Additionally, organosolv pretreatment removed 9% of the lignin. The organosolv-pretreated HS showed an increment in methane potential of 21%, while macerated HS produced less methane than the raw substrate, probably due to the loss of non-structural sugars during maceration.

The diurnal patterns of ruminal enzymatic activity and in vitro digestibility of starch, neutral detergent fiber, and protein.

The objective of this study was to determine whether diurnal patterns in starch, neutral detergent fiber (NDF) and protein digestibilities and amylolytic, fibrolytic, and proteolytic activities exist in dairy cows. Rumen fluid was collected from 4 ruminally cannulated Holstein dairy cows before the morning feeding and subsequently every 4 h for a 24-h period. Two of the cows were restricted from feed for 8 h overnight, and the other 2 continued to receive their feed ad libitum, to isolate and quantify the effects of changes in feeding behavior at night. After 2 runs the cows were crossed over between night feeding treatments. Rumen fluid was analyzed for enzymatic activity and in vitro starch, NDF, and nitrogen digestibility. Circadian rhythm analyses of enzymatic activity and in vitro digestibility were conducted by fitting the linear form of a cosine function with a 24-h period. Patterns were observed in activity for amylase, lichenase, endoglucanase, and xylanase, with the highest activities observed at the time points subsequent to milking and feed delivery. Protease activity was unaffected by either feeding treatment or possible feeding behavior. When fitted to a cosine function, all the parameters tested followed a daily pattern that was sensitive to the overnight availability of feed, although the parameters responded differently to the feeding treatment. The patterns displayed by in vitro digestibility results of starch, NDF, and nitrogen, across the various fluid collection time points, were highly variable. The time at peak (acrophase) observed in the enzymatic analysis did not correspond to those observed in the in vitro analysis. These results suggest that different interpretations should be given to enzymatic activities and in vitro digestibility values, and the time of rumen fluid collection relative to feeding time should be considered and reported when rumen fluid is used for research or commercial purposes. Maximum digestibility appears in fact to be reached around 4 to 5 h after the main ration delivery for NDF and starch and around ration delivery for protein.

Cardiovascular mortality in patients with acute and chronic coronary syndrome: insights from the clinical evidence on ticagrelor.

OBJECTIVE: The purpose of this review is to discuss cardiovascular mortality as clinical outcome in the setting of both acute and chronic coronary syndromes (ACS and CCS) with a focus on the clinical evidence supporting the mortality benefit of ticagrelor across multiple subpopulations. MATERIALS AND METHODS: Papers considered for this review were retrieved from a PubMed search, using different combinations of keywords (e.g., mortality AND coronary syndrome AND dual antiplatelet therapy AND ticagrelor), without limitations in terms of publication date and language. RESULTS: Prevention of ischemic events and death is of outmost relevance in patients with ACS and CCS, given the high rate of recurrence of such events and fatalities. Owing to the evolving nature of patients with CCS, characterized by a broad spectrum of clinical presentations and previous medical history, as well as the advances in the therapeutic and invasive management of ACS, greater attention to the rate of hard clinical outcomes, improvement in the long-term prognosis, and reduction in the residual risk of recurrent events are increasingly reported among cardiologists. Dual antiplatelet therapy (DAPT) is the cornerstone of antithrombotic therapy aimed at lowering the rate of ischemic events and death in patients treated both conservatively and invasively after ACS, as well as improving prognosis in patients with CCS. Significant differences are emerging among oral P2Y12 inhibitors with regards to mortality benefit. CONCLUSIONS: Ticagrelor is an effective and well-tolerated option to attain a meaningful and clinically relevant reduction in cardiovascular mortality in both acute and chronic settings across a broad range of high-risk patient subpopulations with an acceptable payoff in terms of bleeding risk.

Systematic review and meta-analysis: Artificial intelligence for the diagnosis of gastric precancerous lesions and Helicobacter pylori infection.

BACKGROUND: The endoscopic diagnosis of Helicobacter-pylori(H.pylori) infection and gastric precancerous lesions(GPL), namely atrophic-gastritis and intestinal-metaplasia, still remains challenging. Artificial intelligence(AI) may represent a powerful resource for the endoscopic recognition of these conditions. AIMS: To explore the diagnostic performance(DP) of AI in the diagnosis of GPL and H.pylori infection. METHODS: A systematic-review was performed by two independent authors up to September 2021. Inclusion criteria were studies focusing on the DP of AI-system in the diagnosis of GPL and H.pylori infection. The pooled accuracy of studies included was reported. RESULTS: Overall, 128 studies were found (PubMed-Embase-Cochrane Library) and four and nine studies were finally included regarding GPL and H.pylori infection, respectively. The pooled-accuracy(random effects model) was 90.3%(95%CI 84.3-94.9) and 79.6%(95%CI 66.7-90.0) with a significant heterogeneity[I2=90.4%(95%CI 78.5-95.7);I2=97.9%(97.2-98.6)] for GPL and H.pylori infection, respectively. The Begg's-test showed a significant publication-bias(p = 0.0371) only among studies regarding H.pylori infection. The pooled-accuracy(random-effects-model) was similar considering only studies using CNN-model for the diagnosis of H.pylori infection: 74.1%[(95%CI 51.6-91.3);I2=98.9%(95%CI 98.5-99.3)], Begg's-test(p = 0.1416) did not show publication-bias. CONCLUSION: AI-system seems to be a good resource for an easier diagnosis of GPL and H.pylori infection, showing a pooled-diagnostic-accuracy of 90% and 80%, respectively. However, considering the high heterogeneity, these promising data need an external validation by randomized control trials and prospective real-time studies.

Diagnostic Accuracy of EndoFaster® and Narrow-Band Imaging Endoscopy in Patients with Impaired Gastric Acid Secretion: A Real-Time Prospective Study.

BACKGROUND: EndoFaster® analyzes gastric juice in real time during gastroscopy allowing the detection of hypo-achlorhydric conditions, like corpus atrophic gastritis. Narrow-band imaging (NBI) endoscopy allows to accurately detect and perform target biopsies in areas of intestinal metaplasia, a histological change often associated to corpus atrophic gastritis. AIMS: To compare the diagnostic accuracy of EndoFaster® with histological evaluation for corpus atrophic gastritis through high-resolution (HR) NBI targeted biopsies. METHODS: Prospective study on consecutive adult patients undergoing gastroscopy between April and November 2018. Patients in therapy with proton pump inhibitors, previous gastric surgery, and/or known gastric neoplasia were excluded. At the beginning of gastroscopy, gastric juice was aspirated and analyzed by EndoFaster® in 15 seconds. Endoscopists were blinded to the report of EndoFaster®. Evaluation of gastric mucosa in HR-white light was firstly performed, then with HR-NBI allowing to perform targeted biopsies on areas suspected for intestinal metaplasia; otherwise, biopsies were performed according to the updated Sydney System protocol and sent for histopathological evaluation. RESULTS: Overall, 124 patients were included [64% F; 56 (18-85) years]. Corpus atrophic gastritis was present in 41.9% of patients. EndoFaster® showed an accuracy for corpus atrophic gastritis diagnosis, compared to histopathological evaluation as gold standard, of 87.1% and a sensitivity, specificity, PPV, and NPV of 78.8%, 93.1%, 89.1%, and 85.9%, respectively. pH showed a positive correlation with the severity score of atrophy (r = 0.67, 95% CI: 0.73-0.81, and p < 0.0001). EndoFaster® allowed to diagnose corpus atrophic gastritis in 3.7% of patients negative to NBI (corpus atrophic gastritis without intestinal metaplasia). CONCLUSION: EndoFaster® seems a promising tool to diagnose corpus atrophic gastritis. The evaluation of hypo-achlorhydria during gastroscopy can address bioptic sampling in corpus atrophic gastritis patients without intestinal metaplasia.

Effects of Saccharomyces cerevisiae, medium and forage type and their interactions on in vitro ruminal fermentation.

The objective of this study was to investigate the effects of a live yeast, Saccharomyces cerevisiae CNCM I-1077, at four doses (0, 1×105, 1×106 and 1 × 107 cfu/mL) according to the reducing medium used [Goering-Van Soest (GV), McDougall (MD) or Kansas State (KS)] on in vitro ruminal neutral detergent fibre digestibility (NDFd), rate of digestion of NDF (kd), organic matter digestibility (OMd), dry matter digestibility (DMd), pH as well as volatile fatty acids (VFA) concentration, using two forages (oat hay and wheat straw) with differing chemical composition. The maximum in vitro NDFd, DMd, OMd as well as kd were obtained with dose 1 × 106 cfu/mL, although differences between doses were not always significant. The pH estimates were the lowest with the 1 × 107 cfu/mL dose, but the differences were not all significant; however, 1 × 107 cfu/mL corresponded to significantly lower pH estimates compared to the control and 1×105 (6.51 vs. 6.60 and 6.59, respectively). The decrease in pH was accompanied by an increase in VFA concentrations as the yeast dose increased. The KS medium resulted in the lowest digestibility estimates, pH estimates as well as kd, regardless of yeast dose. The 1 × 106 cfu/mL was the better performing yeast dose in vitro resulting in higher digestibility estimates which indicates the yeasts ability to stimulate the microorganisms within the rumen by beneficially modifying rumen environment, thus promoting microbiota activity. The MD and GV media provide better environments for fermentation than the KS medium, resulting in higher in vitro NDFd, DMd, OMd, pH estimates as well as rate of NDF digestion. The MD and GV are also the media that resulted in more consistent results when analysing the effects of the live yeast. Our data suggest that the in vitro conditions have to be carefully chosen to be able to demonstrate rumen fermentation shifts with the use of live microbial additives.

Elemental sulfur-based autotrophic denitrification in stoichiometric S0/N ratio: Calibration and validation of a kinetic model.

The inclusion of S0 hydrolysis in a kinetic model of autotrophic denitrification has been recently proposed; however the model has not been calibrated or validated yet. Thus, a new methodology was developed and applied to calibrate and validate this kinetic model for the first time. An inoculum adapted from a poultry wastewater treatment plant at stoichiometric S0/NO3- ratio was used. The model was calibrated with batch data (initial nitrate concentrations of 50 and 6.25 mg NO3--N/L) at an S0/N ratio = 2.29 mg S/mg N and validated with seven different batch data. The sensitivity analysis showed that the most sensitive parameters are related to S0 hydrolysis. The kinetic model was successfully calibrated with the new methodology and validated, with Theil inequality coefficient values lower than 0.21. Thus, the proposed model and methodology were proved to be well suited for the simulation of elemental sulfur-based autotrophic denitrification in batch systems.