Effect of lysozyme combined with hydrothermal pretreatment on excess sludge and anaerobic digestion.

Anaerobic digestion (AD) is widely employed for sludge stabilization and waste reduction. However, the slow hydrolysis process hinders methane production and leads to prolonged sludge issues. In this study, an efficient and eco-friendly lysozyme pre-treatment method was utilized to address these challenges. By optimizing lysozyme dosage, hydrolysis and cell lysis were maximized. Furthermore, lysozyme combined with hydrothermal pretreatment enhanced overall efficiency. Results indicate that: (1) When lysozyme dosage reached 90 mg/g TS after 240 min of pretreatment, SCOD, soluble polysaccharides, and protein content reached their maxima at 855.00, 44.09, and 204.86 mg/L, respectively. This represented an increase of 85.87%, 365.58%, and 259.21% compared to the untreated sludge. Three-dimensional fluorescence spectroscopy revealed the highest fluorescence intensity in the IV region (soluble microbial product), promoting microbial metabolic activity. (2) Lysozyme combined with hydrothermal pretreatment significantly increased SCOD, soluble proteins, and polysaccharide release from sludge, reducing SCOD release time. Orthogonal experiments identified Group 3 as the most effective for SCOD and soluble polysaccharide release, while Group 9 released the most soluble proteins. The significance order of factors influencing SCOD, soluble proteins, and polysaccharide release is hydrothermal temperature > hydrothermal time > enzymatic digestion time.(3) The lysozyme-assisted hydrothermal pretreatment group exhibited the fastest release and the highest SCOD concentration of 8,135.00 mg/L during anaerobic digestion. Maximum SCOD consumption and cumulative gas production increased by 95.89% and 130.58%, respectively, compared to the control group, allowing gas production to conclude 3 days earlier.

Effects of Saccharomyces cerevisiae and Bacillus subtilis on in vitro fermentation in the rumen of Hu sheep.

BACKGROUND: The demand for animal products is increasing in developing countries due to population growth. However, livestock production contributes significantly to global warming, accounting for 25%. Probiotics can help improve livestock efficiency by enhancing gut microbes and fat metabolism. They can modify rumen populations, enhance fermentation, reduce methane emissions and improve feed digestion. In this study, the goal was to determine the most effective method of reducing methane emissions in the rumen of sheep in vitro by adding different concentrations of Saccharomyces cerevisiae and Bacillus subtilis. RESULTS: Adding 8 × 106 CFU g-1 S. cerevisiae during fermentation reduced pH levels after 48 h. This also increased the concentrations of NH3-N, microbial protein and total gas production. At the same time, it decreased methane emissions. Furthermore, adding 20 × 106 CFU g-1 B. subtilis to the mixture increased total gas production (TGP) and methane production, with the highest production observed after 48 h. However, it did not affect pH levels after 48 h. CONCLUSION: It can be concluded that S. cerevisiae had significantly increased microbial protein and NH3-N concentrations after fermentation without altering pH. Additionally, the addition of S. cerevisiae enhanced TGP and reduced methane emissions. It is worth noting that TGP increased because B. subtilis was added at a concentration of 20 × 106 CFU g-1, with no significant differences between concentrations. Therefore, we recommend adding S. cerevisiae and B. subtilis to the diet at doses of 8 and 20 × 106 CFU g-1, as it resulted in higher TGP and reduced methane emissions. © 2024 Society of Chemical Industry.

Discovery of delayed gas production after implantation of a continuous-flow left ventricular assist device and a preliminary exploration of the mechanisms of its occurrence.

Objective: To characterize the gas production phenomenon in the animal model of left ventricular assist device (LVAD), and study its mechanism. Methods: An in vitro bubble precipitation experiment was conducted, and the blood samples of Parma spp. animals were divided into ordinary group and oxygen-enriched group according to whether they were oxygenated or not at the time of blood collection, and a static control group was set up respectively. Blood gases were drawn and analyzed before and after the experiment. Activate the pump, and the number of air bubbles in the loop was measured by ultrasound at different rotational speeds; CFD was applied to simulate the flow field in the blood pump, and pressure, fluid velocity vector and shear force diagrams were plotted, and a thrombus model was constructed and the flow field was simulated and plotted as a cloud diagram. Results: There was a statistical difference in the number of bubbles in the inflow and outflow tubes of the blood pump (P values of 0.04 and 0.023, respectively), and the number of bubbles in the outflow tubes of both groups was significantly higher than the number of bubbles in the inflow tubes. The number of bubbles in the tubes of both the oxygen-enriched and normal groups was significantly higher than that in the inflow group. In both the normal and oxygen-enriched groups, more gas was produced at higher speeds than at lower speeds. Blood gas analysis showed that the reduced gas composition in the blood was mainly oxygen. Flow field simulation results: the high rotation speed group had lower central pressure and greater scalar shear. The thrombus simulation group was more prone to turbulence, sudden pressure changes, and greater shear than the normal group. Conclusion: Blood gas production is associated with higher partial pressures of blood oxygen, higher rotation speed, and intrapump thrombosis, and the mechanism of pump gas production is degassing of dissolved gases rather than cavitation of water, and the gas released is most likely to have oxygen. The degassing phenomenon is an warning factor for pump thrombosis.

Dietary incorporation of magnetic bentonite nanocomposite: impacts on in vitro fermentation pattern, nutrient digestibility, and growth performance of Baluchi male lambs.

Background: Incorporation of bentonite into the diets of ruminants can be helpful to maximize their performance. Modifying the structure of bentonite to nano and nanocomposite has improved their chemical stability and physicochemical properties, enhancing adsorption, absorption, and cation exchange capacity. Aims: This study aimed to assess the effect of magnetic bentonite nanocomposite (MBNC) on in vivo and in vitro fermentation process patterns, nutrient digestibility, and growth performance of Baluchi male lambs. Methods: Effects of control (basal diet), natural bentonite (NB) (10 g/kg dry matter (DM)), processed bentonite (PB) (5 and 10 g/kg DM basal diet), and MBNC (5 and 10 g/kg DM basal diet) on gas production (GP), and the fermentation process were determined using in vitro GP technique. For the in vivo experiment, 20 Baluchi male lambs were used with 4 experimental treatments: control, NB (5 g/kg DM), PB (5 g/kg DM), and MBNC (5 g/kg DM) and 5 replications in a completely randomized design for 60 consecutive days. Results: The potential for GP and its fractional rates were significantly decreased and increased in MBNC, respectively (P<0.01). The lowest cumulative GP, and CH4 yield were observed in MBNC (P<0.05). In vitro, DM and organic matter (OM) digestibility and all fermentation parameters increased with the addition of two levels of MBNC to the culture medium (P<0.01). Except for feed conversion ratio (FCR), other growth performance parameters increased with the addition of MBNC to the diet (P<0.01). The ruminal pH, total volatile fatty acids (TVFA), acetate, and propionate significantly increased when MBNC incorporated to the diet (P<0.01). The NH3-N (P<0.001) was significantly decreased in MBNC. The bentonite supplementation decreased acetate to propionate (P=0.001) compared to the control. Conclusion: Adding MBNC at the 5 g/kg diet DM level can be used as a useful supplement to optimize rumen fermentation pattern, reduce methane production, and increase lamb performance.

Determination of nutritional value and methane production potential of styrax tree (Styrax officinalis L.) leaves.

This study aimed to determine the effect of nutritional values of the "styrax tree" (Styrax officinalis L.) on in vitro gas production, organic matter digestibility (OMD), and metabolic energy (ME) content. In this study, styrax leaf samples were collected for analysis in three different periods: May, July and September. According to the analysis results, crude ash (CA), dry matter (DM), crude fat (CF), acid detergent fiber (ADF) values, and neutral detergent fiber (NDF) increased in September compared to May and July. In September, compared to May, CA has increased by 23 %, DM by 64 %, CM by 30.5 %, ADF by 9.8 %, and NDF by 9.8 %. During the vegetation period, there was an increase in dry matter content in parallel with maturation. The dry matter content of Styrax tree leaves (STL) increased in May (30 %), July (40 %) and September (50 %). Crude protein amounts were found 19 % in May, 17 % in July, and 15 % in September. As the STL grows, decreases in CP, which plays a role in plant growth, and increases in the cell membrane were observed. The CF content in STL changed to 3.2 %, 4.4 %, and 4.3 % in May, July, and September, respectively, with the highest value determined in July and very close to the September value. CA content in styrax tree plants varied by 8.58 % in May, in July by 9.86 %, and in September by 10.56 %. As the amount of dry matter increased according to the periods, the amount of CA also increased. NDF and ADF levels increased in parallel with the vegetation period's development in STL. NDF was found to be 37.5 %, 39.0 %, and 41.5 % according to the periods. ADF amount was found 27 % in May, 28.5 % in July, and 30 % in September. Metabolic energy varied between 8.86 and 10.06 (MJ/kg KM) depending on the periods. When organic matter digestion levels were examined, it was seen that the highest OMD was in July with 58.71 %. Gas production was determined by incubations of 0, 3, 6, 12, 24, 48, 72, and 96 h, and the maximum gas measurement value was in September, July, and May, respectively. As a result of the study, STL can be a good alternative feed source for ruminants when adequate amounts of high-quality feed materials cannot be provided.

Optimizing acid microemulsions for cleaner gas production: A study on enhanced adsorption characteristics and implications in retardation.

The ultralow interfacial tension between the oil and aqueous phases and the solubilization characteristics in microemulsion systems make them useful for surface cleaning and enhanced oil recovery applications. Microemulsions can form an adsorbed barrier on rock, reducing the acid-rock reaction rate. However, as acid retardation additives, the adsorption patterns of microemulsions are not clearly defined. In this study, microemulsions composed of various electrical surfactants, oil cores, and oil core additives were obtained, and their phase behaviors were investigated. Through adsorption and reaction experiments, cleaning microemulsions that enhance adsorption effects were identified, and their adsorption patterns and adaptability under flow conditions were evaluated. The results demonstrate that incorporating negatively charged polar compounds forms an enhanced adsorption microemulsion characterized by an average droplet size of less than 30 nm after mixing with the acid. The introduction of negatively charged polar compounds resulted in a 177 % increase in adsorption and an 81 % improvement in static retardation effect. Dynamic adsorption tests indicate that the pseudo-second-order model more accurately describes the kinetics of dynamic adsorption of microemulsions on rock surfaces. Under a fixed flow rate, the dynamic retardation rate increased with the concentration of the microemulsion. In practical acidification, the adsorption of microemulsions results mainly from combined electrostatic forces and fluid scouring, characterized by a continuous process of adsorption and desorption. Scanning electron microscope also confirmed that microemulsions can form an adsorptive film on the rock, reducing the acid-rock reaction rate. This study offers practical guidelines for the selection and application of retardation additives, aiming to enhance the ecological compatibility of chemical treatments in low-permeability limestone reservoirs.

Enforcing Hopelessness: Complicity, Dependence, and Organizing in Frontline Oil and Gas Communities.

Fossil fuel companies hold enormous political, economic, and knowledge production power. Recently, industry operators have pivoted from pushing climate denialism to campaigns aimed at individualizing responsibility for climate crisis. In this paper, we focus on one related outcome of such efforts - people's experiences of complicity - here in the context of unconventional oil and gas (UOG) production. We ask: How do mobilized activists experience fossil fuel scapegoating, and what does it mean for their goals as they organize against UOG production? We show that even activists fighting UOG production feel complicit in fossil fuel production, and these feelings of complicity diminish their demands for UOG accountability. We argue that these outcomes have been especially pernicious in cultural contexts like that of the United States, where neoliberal ideologies are normalized, centering personal responsibility, individualization, and identification as consumers rather than citizens. We marshal an extensive qualitative dataset and advance a theory of complicity as a way to understand: a) how social movements intersect with neoliberalized patterns of life; b) how experiences of complicity affect activism; and c) how this may contribute to fossil fuel firms' goals of undercutting organizing. We end by examining how a sub-set of activists works to dismantle this complicity narrative.

Non-thermal technologies for broiler litter processing: Microbial safety, chemical composition, nutritional value, and fermentation parameters in vitro.

BACKGROUND: Annually, a massive amount of broiler litter (BL) is produced in the world, which causes soil and surface water pollution due to its high nitrogen content and microbial count. While ruminants can use this non-protein nitrogen (NPN) source for microbial protein synthesis. This issue becomes more critical when protein sources are unavailable or very expensive. One of the sources of NPN is BL which is produced at a considerable amount in the world yearly. OBJECTIVES: This aim of this research was to conduct a survey of non-thermal technologies such as electrocoagulation (EC), ultraviolet (UV) radiation, and ultrasound (US) waves on the microbial safety and nutritional value of BL samples as a protein source in ruminant diets. MATERIALS AND METHODS: The methodology of this study was based on the use of an EC device with 24 V for 60 min, UV-C light radiation (249 nm) for 1 and 10 min, and US waves with a frequency of 28 kHz for 5, 10 and 15 min to process BL samples compared with shade-dried samples. Chemical composition and nutritional values of processed samples were determined by gas production technique and measurement of fermentation parameters in vitro. RESULTS: Based on the results, microbial safety increased in the samples processed with the US (15 min). The EC method had the best performance in reducing the number of fungi and mould. However, none of the methods could remove total bacteria and fungi. Digestibility of BL was similar in shade-dried, EC, and US (10 min) treatments. In general, the use of EC and US15 without having adverse effects on gas production caused a decrease in the concentration of ammonia nitrogen. In contrast, it caused a decrease in neutral detergent fibre (NDF) in the investigated substrate. CONCLUSIONS: In general, it can be concluded that the use of US5 and EC methods without having a negative effect on the parameters of gas production and fermentation in vitro, while reducing NDF, causes a significant reduction in the microbial load, pathogens, yeast, and mould. Therefore, it is suggested to use these two methods to improve feed digestibility for other protein and feed sources.

Modular Synthesis of High Performance Energetic Biocidal Bicyclic Compounds Derivated from Iodopyrazoles.

Modular synthesis can combine different functional module to flexibly regulate comprehensive properties and study the diversity of compounds. This study established a modular bicyclic synthesis strategy of combining polynitro energetic module with iodine-containing biocidal module. Compounds 1-6 with high iodine content (48.72-69.56%) and high thermal stability (Td: 172-304 ˚C) were synthesized and exhaustively identified. By modular synthesis, the detonation properties and gas-production of 3-6 improved greatly expanding their biocidal efficacy and maintained the iodine atomic utilization of iodine-containing module. Notably, 4,5-diiodo-3,4',5'-trinitro-1,3'-bipyrazole (5) and 3,5-diiodo-4,4',5'-trinitro-1,3'-bipyrazole (6) exhibit high detonation velocities (D: 5903 m s-1, 5769 m s-1, respectively) and highest gas production of 212.85 L mol-1 and 217.66 L mol-1 after decomposition. This study diversifies polyiodio-nitro compounds, and also inspire the implementation of similar synthesis strategies to provide family-level synthetic solutions to energetic biocidal materials.

In vitro fermentation potential of gut endogenous protein losses of growing pigs.

Fermentation of dietary and endogenous protein in the hindgut is generally considered detrimental to the health of pigs. We investigated the in vitro fermentation potential of porcine endogenous protein in ileal digesta and colonic mucus, using a N-free buffer with an excess of fermentable carbohydrates. Urea, whey protein isolate (WPI, positive control), WPI hydrolysate (WPIH), and combinations of the latter two were used to validate the assay. A new biphasic model, including a linear end simulation, fitted to the gas production data over a 48-h period identified the time point when substrate fermentation ended. A higher degree of hydrolysis of WPI resulted in a higher maximum gas production rate (Rmax, P < 0.01). Differences in Rmax and the time required to reach Rmax were observed among ileal digesta samples, with Rmax increasing with the insoluble protein content, and the highest Rmax occurring with colonic mucus samples (P < 0.05). The endogenous proteins entering the large intestine of pigs can ferment more rapidly compared to highly soluble and digestible protein sources, with Rmax positively correlated with decreasing solubility of endogenous nitrogenous components.

Protein fermentation in the hindgut of pigs can impact their health, affecting factors like growth rates and feed efficiency. Besides dietary protein, up to 50% of the protein entering the large intestine of growing pigs may be of endogenous origin. Therefore, we explored the fermentation potential of endogenous proteins compared to a well-known protein source, whey protein isolate (WPI). In developing and validating an in vitro gas production technique, we employed urea, WPI, WPI hydrolysate, and various combinations as substrates. The study introduces a new biphasic model for in vitro gas production, offering a detailed analysis of the fermentation process over a 48-h period. Our results revealed that porcine endogenous proteins can undergo rapid fermentation because the maximum gas production rate was higher compared to WPI. This insight is crucial for understanding the dynamics of protein fermentation in pigs. Additionally, we explored the solubility and molecular size of proteins, providing a comprehensive understanding of their fermentation characteristics. We found that endogenous proteins were less soluble compared to WPI but contained more smaller peptides. Unraveling the complexities of protein fermentation in pigs contributes to improvement of feed formulation for optimal gut health.

Effect of 3-Nitropropionic Acid at Different Doses on In Vitro Rumen Fermentation, Digestibility, and Methane Emissions of Grazing Yak and Cattle.

3-nitropropionic acid (3NPA) has been proposed as an useful modifier to mitigate ruminal enteric methane emissions. However, few studies investigated the effects of 3NPA on ruminal fermentation characteristics of grazing ruminants in vitro. Rumen fluid from grazing yak and cattle were collected and incubated with additions of 0, 8, and 16 mM 3NPA. The total gas production, CH4 production, and dry matter digestibility significantly decreased with increasing 3NPA doses in both ruminant species (p < 0.05) and methane production decreased to almost 100% in cattle at 8 mM NPA but not yak, while H2 accumulation showed an opposite trend. The total fatty acid (TVFA) production, acetate concentration, and propionate concentration in cattle decreased as 3NPA doses increased at 12 and 24 h incubation. For yak, the H2 accumulation reached its apex at 8 mM NPA (p < 0.05). The TVFA in yak decreased significantly with increasing 3NPA doses at 12 and 72 h incubation. Moreover, the acetate concentration and propionate concentration in yak decreased as 3NPA doses increased at 12 and 24 h incubation. Overall, these findings demonstrated that 3NPA could be used as a strategy to mitigate methane emissions; although, it negatively affected the dry matter degradability in vitro.

Chemical Composition and Nutritive Value of Almond Hulls from Two Almond Varieties and Influence of Including Almond Hulls in the Diet on In Vitro Ruminal Fermentation and Methane Production.

Almond hulls (AH) are frequently used in dairy ruminant feeding, but information on variability of their nutritive value and their potential effects on CH4 production is still scarce. The influence of almond variety (Guara vs. Soleta) on chemical composition and energy value of AH was investigated using 10 samples per variety collected in 2 consecutive years. Guara-AH had greater (p ≤ 0.015) ash, protein, and fat content, but lower (p ≤ 0.001) fiber than Soleta-AH. The metabolizable energy content estimated from chemical composition and in vitro gas production was 8.5% greater for Guara than for Soleta samples. Harvesting year significantly affected most of the chemical fractions. The in vitro ruminal fermentation of diets for dairy ruminants including increasing amounts of dried AH (8, 16 and 24% of the total diet; fresh matter basis) indicated that AH can be included up to 16% of the diet, partially substituting corn, wheat bran and sugar beet pulp without detrimental effects on in vitro volatile fatty acid (VFA) production. In contrast, when AH replaced alfalfa hay and corn, VFA production was reduced at all levels of AH inclusion. No antimethanogenic effects of AH were detected in the in vitro incubations.

Efficacy of Salvia officinalis Shrub as a Sustainable Feed Additive for Reducing Ruminal Methane Production and Enhancing Fermentation in Ruminants.

The objective of this study was to evaluate the effects of the inclusion of dried Salvia officinalis (SO) shrub leaves on nutrient degradability, ruminal in vitro fermentation, gas production (GP), methane (CH4), and carbon dioxide (CO2) productions. Dried and ground SO shrub leaves were included at 0% (control), 0.5%, 1%, 1.5%, and 2% DM of a diet consisting of (per kg DM) 500 g concentrate feed mixture, 400 g berseem hay, and 100 g rice straw. The diet was incubated for 48 h. The asymptotic GP and the rate of GP changed linearly and quadratically (p < 0.01), with the highest GP observed at 1% inclusion of SO and then decreasing thereafter with greater inclusion (i.e., 1.5% and 2%), while CH4 production and its rate decreased linearly (p < 0.01) with all levels of SO inclusion. A linear increase in CO2 production and its rate was also found with an increasing level of SO inclusion in the diet (p < 0.05). Furthermore, the degradability of DM, NDF, and the concentration of total short-chain fatty acids and acetate changed linearly and quadratically, with the greatest being found at 1% SO inclusion and then steadily declining after (p < 0.01) with the 1.5% and 2% inclusion levels. Meanwhile, the propionate, NH3-N, and microbial crude protein levels showed similar trends, with the plateau found at 1% inclusion of SO, where there was no change in butyrate concentration. Moreover, the pH, metabolizable energy, and partitioning factor (PF24) also changed linearly and quadratically (p < 0.05), where the pH and PF24 were considerably reduced and ME increased with a 1% inclusion of SO (p < 0.05). In summary, SO at 1% inclusion in the diet showed the potential to improve gas production kinetics, nutrient degradability, and the ruminal fermentation profile, with a more significant reduction in ruminal CH4 production suggesting that SO at 1% could be included in the ruminant diet to reduce their carbon footprint and increase the production performance.

Effects of Black Soldier Fly (Hermetia illucens L., BSF) Larvae Addition on In Vitro Fermentation Parameters of Goat Diets.

The purpose of this experiment was to evaluate the effects of different levels of BSF on rumen in vitro fermentation gas production, methane (CH4) production, ammonia nitrogen (NH3-N), and volatile fatty acids (VFAs). The experiment comprised four treatments, each with five replicates. The control group contained no BSF (BSF0), and the treatment groups contained 5% (BSF5), 10% (BSF10), and 15% (BSF15) BSF, respectively. Results showed that at 3 h, 9 h, and 24 h, gas production in BSF5 and BSF10 was significantly higher than in BSF0 and BSF15 (p < 0.05). Gas production in BSF5 and BSF10 was higher than in BSF0, while gas production in BSF15 was lower than in BSF0. At 6 h and 12 h, CH4 emission in BSF15 was significantly lower than in the other three groups (p < 0.05). There were no differences in the pH of in vitro fermentation after BSF addition (p > 0.05). At 3 h, NH3-N levels in BSF10 and BSF15 were significantly higher than in BSF0 and BSF5 (p < 0.05). At 6 h, NH3-N levels in BSF5 and BSF10 were significantly higher than in BSF0 and BSF15 (p < 0.05). Acetic acid, propionic acid, butyric acid, and total VFAs in BSF0, BSF5, and BSF10 were significantly higher than in BSF15 (p < 0.05). In conclusion, gas production, CH4 emission, NH3-N, acetic acid, propionic acid, butyric acid, and VFAs were highest in BSF5 and BSF10 and lowest in BSF15.

Comparative study on the thermal runaway characteristics of Li(NixCoyMnz)O2 batteries.

Lithium-ion batteries (LIBs) generate substantial gas during the thermal runaway (TR) process, presenting serious risks to electrochemical energy storage systems in case of ignition or explosions. Previous studies were mainly focused on investigating the TR characteristics of Li(NixCoyMnz)O2 batteries with different cathode materials, but they were conducted in isolation. In this study, the thermal runaway characteristics of prismatic cells that use Li(NixCoyMnz)O2 (with x ranging from 0.33 to 0.9) cathode materials in an inert environment, which are commonly used or proposed for energy storage applications, are examined. The findings of this research show that the normalized gas generation rate remains consistent, regardless of the battery capacity or experimental chamber volume, with a value of 0.1 ± 0.03 mol∙Ah⁻1. High-capacity cells have short jetting durations, and a high nickel content leads to increased mass loss rates. The flammability limits of the gases expelled during thermal runaway, represented by the lower flammability limit (LFL), remain stable at 8 ± 1.8 % with minimal variations. However, the upper flammability limit (UFL) varies significantly, ranging from 30 % to 60 %. Increasing the battery capacity or reducing the experimental chamber volume increases the explosion index. The explosive, combustibility, and jetting duration characteristics of the emitted gases from five different battery chemical compositions provide valuable insights for risk assessment in future electrochemical energy storage systems.

Enhancing Rumen Fermentation and Bacteria Community in Sika Deer (Cervus nippon) through Varying Levels of Dragon Fruit Peel Polyphenolic Extract: An In Vitro Study.

The aim of this study is to investigate the effect of dragon fruit peel polyphenolic extract (DFPE) on gas production, rumen fermentation, and bacterial communities in sika deer using an in vitro technique. Three treatments with different DFPE levels (DFPE0, base diet; DFPE5, base diet + 5 mg/g DFPE; DFPE10, base diet + 10 mg/g DFPE, respectively; n = 6) were implemented. The phenolic composition of DFPE, gas production (GP), ammonia nitrogen (NH3-N), volatile fatty acid (VFA), and bacteria communities was evaluated after 24 h of incubation. The results showed that GP and NH3-N were reduced by DFPE supplementation. Total VFA, isovaleric acid, and valeric acid were increased (p < 0.05) by the addition of DFPE. No changes (p > 0.05) were observed in pH, acetic acid, propionic acid, isobutyric acid, butyric acid, and the ratio of acetic acid to propionic acid. Additionally, the alpha indexes, including Sobs, Shannon, and Ace, were increased by DFPE supplementation. Moreover, at the phylum level, DFPE supplementation increased (p = 0.01) Bacteroidota but reduced (p < 0.01) Firmicutes. At the genus level, compared to DFPE0, the DFPE10 had increased relative abundances of Rikenellaceae_RC9_gut_group (p < 0.01), norank_f_Muribaculaceae (p = 0.01), Lachnospiraceae_NK3A20_group (p < 0.01), Christensenellaceae_R-7_group (p < 0.01), and NK4A214_group (p < 0.01), decreased relative abundances of Streptococcus (p < 0.01), Oribacterium (p = 0.01), and Enterococcus (p < 0.01). Compared to DFPE0, DFPE5 had no change (p > 0.05) in all bacteria at the genus level except for decreased relative abundance of Enterococcus (p < 0.01). These results indicated that DFPE may be able to be used as a feed additive to enhance fermentation parameters and improve ruminal bacteria communities in Sika deer.

COVID-19 pandemic, Russia-Ukraine conflict and shale gas development: Evidence from fractional integration.

Although there are papers on the persistence of energy series including the persistence of shale gas, the impact of recent developments such as the Covid-19 pandemic and Russia-Ukraine conflict have been rarely explored in the existing literature. This paper examines the structure of shale gas production in the U.S. by looking at the degree of persistence across different areas, with the aim to determine if shocks in the series are permanent or transitory. Using fractional integration methods (which unlike the conventional methods, allow for the determination of the persistence of energy and non-energy series in a robust manner), and different subsamples that include the Covid-19 pandemic and the Russia-Ukraine war, our results indicate that there is a substantial decrease in the integration order in the total shale gas production in the U.S. as well as in four other plays-Haynesville, Permian, Utica and Eagle Ford. However, no differences are observed with respect to the Russia-Ukraine war. There is another group of four series (Marcellus, Niobrara-Codell, Woodford and Rest of US 'shale') with a very small reduction in the degree of persistence and another group of three series with almost no reduction at all in the order of integration (Barnett, Mississippian and Fayetteville). Several implications in terms of policy are reported at the end of the manuscript.

Effects of yeast culture on in vitro ruminal fermentation and microbial community of high concentrate diet in sheep.

This research aimed to investigate effects of different yeast culture (YC) levels on in vitro fermentation characteristics and bacterial and fungal community under high concentrate diet. A total of 5 groups were included in the experiment: control group without YC (CON), YC1 (0.5% YC proportion of substrate dry matter), YC2 (1%), YC3 (1.5%) and YC4 (2%). After 48 h of fermentation, the incubation fluids and residues were collected to analyze the ruminal fermentation parameters and bacterial and fungal community. Results showed that the ruminal fluid pH of YC2 and YC4 groups was higher (P < 0.05) than that of CON group. Compared with CON group, the microbial protein, propionate and butyrate concentrations and cumulative gas production at 48 h of YC2 group were significantly increased (P < 0.05), whereas an opposite trend of ammonia nitrogen and lactate was observed between two groups. Microbial analysis showed that the Chao1 and Shannon indexes of YC2 group were higher (P < 0.05) than those of CON group. Additionally, YC supplementation significantly decreased (P < 0.05) Succinivibrionaceae_UCG-001, Streptococcus bovis and Neosetophoma relative abundances. An opposite tendency of Aspergillus abundance was found between CON and YC treatments. Compared with CON group, the relative abundances of Prevotella, Succiniclasticum, Butyrivibrio and Megasphaera elsdenii were significantly increased (P < 0.05) in YC2 group, while Apiotrichum and unclassified Clostridiales relative abundances were decreased (P < 0.05). In conclusion, high concentrate substrate supplemented with appropriate YC (1%) can improve ruminal fermentation and regulate bacterial and fungal composition.

Improving water quality and mitigating CH4 and N2O production in urban landscape water simultaneously by optimizing calcium peroxide dosage.

Recent studies show that greenhouse gas (GHG) emissions from urban landscape water are significant and cannot be overlooked, underscoring the need to develop effective strategies for mitigating GHG production from global freshwater systems. Calcium peroxide (CaO2) is commonly used as an eco-friendly reagent for controlling eutrophication in water bodies, but whether CaO2 can reduce GHG emissions remains unclear. This study investigated the effects of CaO2 dosage on the production of methane (CH4) and nitrous oxide (N2O) in urban landscape water under anoxic conditions during summer. The findings reveal that CaO2 addition not only improved the physicochemical and organoleptic properties of simulated urban landscape water but also reduced N2O production by inhibiting the activity of denitrifying bacteria across various dosages. Moreover, CaO2 exhibited selective effects on methanogens. Specifically, the abundance of acetoclastic methanogen Methanosaeta and methylotrophic methanogen Candidatus_Methanofastidiosum increased whereas the abundance of the hydrogenotrophic methanogen Methanoregula decreased at low, medium, and high dosages, leading to higher CH4 production at increased CaO2 dosage. A comprehensive multi-objective evaluation indicated that an optimal dosage of 60 g CaO2/m2 achieved 41.21 % and 84.40 % reductions in CH4 and N2O production, respectively, over a 50-day period compared to the control. This paper not only introduces a novel approach for controlling the production of GHGs, such as CH4 and N2O, from urban landscape water but also suggests a methodology for optimizing CaO2 dosage, providing valuable insights for its practical application.

Temporal Variation and Persistence of Methane Emissions from Shallow Water Oil and Gas Production in the Gulf of Mexico.

Methane emissions from the oil and gas supply chain can be intermittent, posing challenges for monitoring and mitigation efforts. This study examines shallow water facilities in the US Gulf of Mexico with repeat atmospheric observations to evaluate temporal variation in site-specific methane emissions. We combine new and previous observations to develop a longitudinal study, spanning from days to months to almost five years, evaluating the emissions behavior of sites over time. We also define and determine the chance of subsequent detection (CSD): the likelihood that an emitting site will be observed emitting again. The average emitting central hub in the Gulf has a 74% CSD at any time interval. Eight facilities contribute 50% of total emissions and are over 80% persistent with a 96% CSD above 100 kg/h and 46% persistent with a 42% CSD above 1000 kg/h, indicating that large emissions are persistent at certain sites. Forward-looking infrared (FLIR) footage shows many of these sites exhibiting cold venting. This suggests that for offshore, a low sampling frequency over large spatial coverage can capture typical site emissions behavior and identify targets for mitigation. We further demonstrate the preliminary use of space-based observations to monitor offshore emissions over time.