Effects of nanobubble water on digestate soaking hydrolysis of rice straw

This study investigated the performance of combined nanobubble water (NW) and digestate in the soaking hydrolysis process. Two types of NW (CO2NW and O2NW) with digestate were used to soak rice straw for 1, 2, 3, 5, and 7 days. During soaking process, the volatile fatty acids (VFA) concentration in the treatment with O2NW and digestate for 3 days (O2NW-3 d) reached 7179.5 mg-HAc/L. Moreover, the highest specific methane yield (SMY) obtained in this treatment could reach 336.7 NmL/gVS. Although the addition of NW did not significantly increase SMY from digestate soaking, NW could accelerate the rate of methane production and reduce digestion time of T80. The enrichment of Enterobacter in the soaking process was observed when using CO2NW and O2NW as soaking solutions which played important roles in VFA production. This study provides a new insight into environment-friendly enhanced crop straw pretreatment, combining NW and digestate soaking hydrolysis.

[Clinical features and surgical treatment of right cardiac system tumors]

A total of 25 patients with right cardiac system tumors in the Department of Cardiac Surgery, Beijing Anzhen Hospital from January 2012 to October 2022 were retrospectively included in the study. The preoperative data, and information of surgical treatment and perioperative management on these patients were analyzed and summarized. One patient developed pulmonary embolism and died before surgery, and the other 24 patients (16 males and 8 females) received surgical treatment, with an average age of (44.7±10.2) years (24-74 years). Nine patients were diagnosed with malignant tumors. Among the 24 patients who received surgical treatment, two patients died during the perioperative period, in-situ tumor recurrence was seen in three patients within about 1 year after surgery (two patients died without surgery, and one patient died 3 months after surgery), two patients had distant metastasis, and 17 patients had a good prognosis. Right cardiac system tumors are rare, with a high malignant rate, and the clinical manifestations vary greatly. Active surgical intervention is found to be effective, and the prognosis is closely related to the pathological type and extent of tumor invasion.

[Advances in warfarin's anticoagulation therapy in Chinese population after mechanical valve replacement]

Warfarin is an irreplaceable oral anticoagulant for patients with mechanical heart valves, the stable pharmacogenetic-based warfarin dose prediction algorithms have improved the effectiveness and safety of warfarin anticoagulation therapy. Genetic factors are the main factors affecting the stable dose of warfarin. Single nucleotide polymorphisms such as VKORC1 and CYP2C9 affect the anticoagulation effect of warfarin through pharmacodynamic or pharmacokinetic pathways. Age, body surface area, combined use of drugs, and other nongenetic factors also affect the stable dose of warfarin. Previously published algorithms for warfarin dose prediction included mainly the white race, and most algorithms were constructed using traditional multiple linear regression. However, domestic studies have used machine learning methods to construct warfarin dose prediction algorithms based on the Chinese Han post-mechanical valve replacement population and have achieved better prediction efficiency. This article reviews the advances of warfarin anticoagulation influencing factors and the clinical application of stable dose prediction algorithms.

Modulation of the microRNA-6089/E2F transcription factor2 axis by querceting: implications for osteoblast viability, proliferation, migration, and osteogenic differentiation in fracture healing

Quercetin is widely distributed in plants as a flavonol compound with multiple biological activities. It has been found that quercetin can regulate bone homeostasis through multiple pathways and targets. This study investigated the role and specific molecular mechanisms of quercetin in regulating osteoblast viability, proliferation, migration and osteogenic differentiation. A mouse model of traumatic fracture was established and then 100 mg/kg quercetin corn oil suspension was gavaged at the same time every day for 28 days. miR-6089 and E2F transcription factor 2 (E2F2) expression levels in mice were measured. Fracture healing in mice was observed. MC3T3-E1 cells were transfected with plasmids targeting miR-6089 and E2F2, and cell viability, proliferation, migration, apoptosis, and osteogenic differentiation were determined. The targeting relationship between miR-6089 and E2F2 was verified. In vivo experiments showed that quercetin significantly increased osteocalcin (OCN) expression (P<0.05) and promoted fracture healing in traumatic fracture (TF) mice. miR-6089 expression was down-regulated (P<0.05) and E2F2 expression was up-regulated (P<0.05) in TF mice. Quercetin promoted miR-6089 expression and inhibited E2F2 expression (both P<0.05). In vitro results showed that quercetin promoted miR-6089 expression and inhibited E2F2 expression in a dose-dependent manner (both P<0.05). Quercetin dose-dependently promoted MC3T3-E1 cell viability, proliferation, migration, and osteogenic differentiation, and inhibited MC3T3-E1 cell apoptosis (all P<0.05). Up-regulating miR-6089 further promoted MC3T3-E1 cell viability, proliferation, migration and osteogenic differentiation, and inhibited MC3T3-E1 cell apoptosis (all P<0.05). miR-6089 targeted and regulated E2F2 expression. Up-regulating E2F2 attenuated the promoting effect of up-regulated miR-6089 on MC3T3-E1 cell viability, proliferation, migration, osteogenic differentiation, and inhibition of apoptosis (all P<0.05). We conclude that quercetin enhances osteoblast viability, proliferation, migration, and osteogenic differentiation by modulating the miR-6089/E2F2 axis, thereby promoting fracture healing.

Synergistic effect of hydrothermal sludge and food waste in the anaerobic co-digestion process: microbial shift and dewaterability

While thermal hydrolysis technology is commonly employed for sewage sludge treatment in extensive wastewater treatment facilities, persistent challenges remain, including issues such as ammonia-induced digestive inhibition and reduced productivity stemming from nutrient deficiency within the hydrothermal sludge. In this study, the effects of hydrothermal sludge-to-food waste mixing ratios and fermentation temperatures on anaerobic co-digestion were systematically investigated through a semi-continuous experiment lasting approximately 100 days. The results indicated that anaerobic co-digestion of hydrothermal sludge and food waste proceeded synergistically at any mixing ratio, and the synergistic effect is mainly attributed to the improvement of carbohydrate removal and digestive system stability. However, thermophilic digestion did not improve the anaerobic performance and methane yield. On the contrary, mesophilic digestion performed better in terms of organic matter removal, especially in the utilization of soluble carbohydrates, soluble proteins, and VFAs. Microbial community analysis revealed that the transition from mesophilic to thermophilic anaerobic co-digestion prompts changes in the methane-producing pathways. Specifically, the transition entails a gradual shift from pathways involving acetoclastic and hydrogenotrophic methanogenesis to a singular hydrogenotrophic methanogenesis pathway. This shift is driven by thermodynamic tendencies, as reflected in Gibbs free energy, as well as environmental factors like ammonia nitrogen and volatile fatty acids. Lastly, it is worth noting that the introduction of food waste did lead to a reduction in cake solids following dewatering. Nevertheless, it was observed that thermophilic digestion had a positive impact on dewatering performance.

Effect of reactor operation modes on mitigating antibiotic resistance genes (ARGs) and methane production from hydrothermally-pretreated pig manure

Numerous efforts have been made to enhance the performance of anaerobic digestion (AD) for accelerating renewable energy generation, however, it remains unclear whether the intensified measures could enhance the proliferation and transmissions of antibiotic resistance genes (ARGs) in the system. This study assessed the impact of an innovative pig manure AD process, which includes hydrothermal pretreatment (HTP) and a two-stage configuration with separated acidogenic and methanogenic phases, on biomethane (CH4) production and ARGs dynamics. Results showed that HTP significantly increase CH4 production from 0.65 to 0.75 L/L/d in conventional single-stage AD to 0.82 and 0.91 L/L/d in two-stage AD. This improvement correlated with a rise in the relative abundance of Methanosarcina, a key methanogenesis microorganism. In the two-stage AD, the methanogenic stage offered an ideal environment for methanogens growth, resulting in substantially faster and higher CH4 production by about 10% compared to single-stage AD. Overall, the combined use of HTP and the two-stage AD configuration enhanced CH4 production by 40% compared to traditional single-stage AD. The abundance and diversity of ARGs were significantly reduced in the acidogenic reactors after HTP. However, the ARGs levels increased by about two times in the following methanogenesis stage and reached similar or higher levels than in single stage AD. The erm(F), erm(G), ant(6)-Ia, tet(W), mef(A) and erm(B) were the six main ARGs with significant differences in relative abundances in various treatments. The two-stage AD mode could better remove sul2, but it also had a rebound which elevated the risk of ARGs to the environment and human health. Network analysis identified pH and TVFAs as critical factors driving microbial communities and ARG proliferation in the new AD process. With the results, this study offers valuable insights into the trade-offs between AD performance enhancement and ARG-related risks, pinpointing essential areas for future research and practical improvements.

Determination of effects of thermophilic and hyperthermophilic temperatures on anaerobic hydrolysis and acidogenesis of pig manure through a one-year study

Improving hydrolysis and acidogenesis through thermophilic and hyperthermophilic temperatures is critical for enhancing the anaerobic decomposition of organic waste like pig manure. However, whether higher temperatures can provide more enhanced performance has not been elucidated experimentally. This study, therefore, conducted a 375-day continuous operation experiment at 55 and 70 °C with a 5-day hydraulic retention time. The two temperature reactors entered a stable state after about 200 days and long-term microbial acclimation markedly changed their performances. In the thermophilic and hyperthermophilic reactor, the hydrolysis efficiencies were obtained at 29.7 % and 27.3 % respectively, whereas the acidogenesis efficiency was relatively low at 1.0 % and 3.1 %. Due to the occurrence of methanogenesis, the volatile fatty acid concentration in the thermophilic reactor was only 45 % of that in the hyperthermophilic reactor. The thermophilic reactor exhibited higher bacterial diversity; however, this difference between the two reactors apparently did not correlate with hydrolysis and acidogenesis performance.

Impact of Cadmium Contamination on Fertilizer Value and Associated Health Risks in Different Soil Types Following Anaerobic Digestate Application

Cadmium (Cd) contamination in the soil potentially hampers microbial biomass and adversely affects their services such as decomposition and mineralization of organic matter. It can reduce nitrogen (N) metabolism and consequently affect plant growth and physiology. Further, Cd accumulation in plants can pose health risks through vegetable consumption. Here, we investigated consequences of Cd contamination on fertilizer value and associated health risks following the application of biogas residues (BGR) to various soil types. Our results indicate that the application of BGR to all soil types significantly increased dry matter (DM) yield and N uptake. However, the Cd contamination negatively affected DM yield and N recovery from BGR in a dose-dependent manner. Organic N mineralization from BGR also decreased in Cd-contaminated soils. The highest DM yield and N recovery were recorded in sandy soil, whereas the lowest values were observed in clay soil. Cadmium was accumulated in spinach, and health risk index (HRI) associated with its dietary intake revealed that consuming spinach grown in Cd-contaminated soil, with or without BGR, is unsafe. Among the soil types, values of daily intake of metals (DIM) and HRI were lowest in clay soil and highest in sandy soil. However, the application of BGR curtailed HRI across all soil types. Notably, the application of BGR alone resulted in HRI values < 1, which are under the safe limit. We conclude that soil contamination with Cd reduces fertilizer value and entails implications for human health. However, the application of BGR to the soil can decrease Cd effects.

Optimal deployment of thermal hydrolysis and anaerobic digestion to maximize net energy output based on sewage sludge characteristics

Thermal hydrolysis (TH) is widely employed in combination with anaerobic digestion (AD) to efficiently treat primary sludge and waste-activated sludge in municipal wastewater treatment plants. In this study, four different scenarios-conventional AD (S1), TH-AD (S2), AD-TH-AD (S3), and characteristics-based AD-TH-AD (S4, primary AD only for primary sludge)-were evaluated to determine the optimal deployment of TH and AD for treating primary sludge and waste-activated sludge to maximize net energy output. The maximum net energy output of 4899 MJ/t-TSfed (per ton total solids of sludge fed) was achieved in S4 when assuming the recovered heat was only used for AD heating and surplus heat was wasted, and the net energy output of S4 was 70.8 % higher than that of S1 and 48.6 % higher than that of S2. This remarkable improvement was attributed to a reduction of > 15.2 % in refractory compounds, resulting in a 17 % increase in methane yield. Importantly, this study provides the first comparison of refractory compounds between inter-thermal hydrolysis (inter-TH) and pre-thermal hydrolysis (pre-TH) using a simulated A2O process. Overall, this study provides innovative insights and strategies for enhancing the TH and AD process performance based on the specific characteristics of sewage sludge derived from wastewater treatment plants.

Integration of in-situ and ex-situ power-to-gas (PtG) strategy for simultaneous bio-natural gas production and CO2 emission reduction

A novel system integrating an in-situ and ex-situ power-to-gas (PtG) system was developed in the current study. A continuous stirred-tank reactor (CSTR) was operated using cattle manure as substrate at mesophilic temperature (37 °C ± 2 °C). The CH4 content in the biogas was upgraded to above 95% by H2 injection, which meets the highest criteria for grid injection without requiring CO2 removal. Furthermore, the bio-nature gas production was promoted by external CO2 and H2 injection. The volumetric methane production rate (VMPR) was significantly increased by 739% from 117.4 mL L-1·d-1 to 985 mL⋅L-1⋅d-1, which is higher than in other studies. Meanwhile, the volumetric biogas production rate (VBPR) was increased by 36.9% by H2 injection, increasing the conversion efficiency (82.56%) of the chemical oxygen demand (COD) to CH4. A significant increase in the specific methanogenic activity of dissolved hydrogen (SMA(Hdissolved)) and the enrichment in hydrogenotrophic methanogens (Methanobacterium) demonstrate that the CH4 production pathway was converted from acetoclastic methanogenesis (AM) pathway to hydrogenotrophic methanogenesis (HM) pathway. It is postulated that the change in proportion of different pathways of the CH4 production was caused by the strengthening of key enzymes (coenzyme F420 hydrogenase and coenzyme-B sulfoethylthiotransferase) by H2 injection. The integrated system represents a promising approach to achieve simultaneous CO2 emission reduction and bio-natural gas production.

Generation of High Concentration Free Volatile Fatty Acids from Continuous Anaerobic Digestion of Chicken Manure by Suppressing the Decomposition of Nitrogenous Components

Free volatile fatty acids (free VFA) play a crucial role in the inactivation of pathogens during the anaerobic digestion of animal manure. However, the decomposition of nitrogenous components can release alkaline ammonium-N, which might increase the pH and reduce the concentration of free VFA. In this study, continuous anaerobic digestion of high-solid chicken manure was conducted for 150 days. The results indicated the process stabilized at a pH of approximately 6.0, with total ammonia nitrogen (TAN) of around 7.0 g/L. The resulting concentration of free VFA was only about 3.1 g/L, which might not sufficiently effective for pathogen inactivation. On the 70th day, hydrogen chloride was added into the reactor to adjust the pH to 5.5. This led to a further decrease in pH to 4.3 and TAN to 2.3 g/L. As a result, the concentration of free VFA significantly increased, reaching up to 12.6 g/L. These findings support the potential for generating high levels of free VFA even for nitrogen-rich manure by implementing an appropriate process regulation.

Chemically and biologically driven carbon transformation flow in MSW leachate treated by a high-solids anaerobic membrane bioreactor system

Carbon transformation is important for an anaerobic process but is often overlooked when using an anaerobic membrane bioreactor (AnMBR). Material flow in an AnMBR treating calcium-rich MSW leachate was thus quantitatively investigated to illustrate how chemical and biological factors affect carbon transformation. The results show that a remarkable amount of carbon in the leachate was degraded, with 50.1% of it should be converted into CH₄ and 37.7% of it into CO₂. However, a much smaller value of 40.6% and 14.2% were experimentally obtained. Chemical analysis indicated that the precipitation of calcium carbonate captured 1.23 g/day of carbon. At the same time, about 23.2 g/L HCO₃^- and 16.6 mg/L CH₄ (both as carbon) were dissolved in the liquid. Those features facilitated the high CH₄ (74%) content in biogas. A carbon transformation model was therefore established and showed carbon flow into the gas, liquid, and solid phases, respectively. Carbon existed in biogas, permeate, and discharged sludge was also obtained.

Hotspots and future trends of phosphorus recycling from livestock manure: A bibliometric review

In recent decades, the importance of managing the earth's dwindling phosphorus (P) has grown exponentially, as have efforts to develop a circular economy. Livestock manure represents a P-rich waste product, so recycling P from livestock manure has garnered the attention of scholars worldwide. Based on a global database from 1978 to 2021, this study presents the current status of recycling P from livestock manure and proposes strategies for efficient P utilization. Unlike traditional review articles, this work establishes a visual collaborative network on P recycling from livestock manure of research areas, countries, institutions, and authors through a bibliometric analysis using Citespace and VOSviewer software. The co-citation analysis of literature revealed the development of the main research content in this field, and further clustering analysis illustrated the current key research directions. Keyword co-occurrence analysis identified the hotspots and new frontiers of research in this field. According to the results, the United States was the most influential and actively contributing nation, and China was the country with the tightest international ties. The most popular research area was environmental science, and the Bioresource Technology published the largest number of papers in this area. The research priority was the technologies development of P recycling from livestock manure, of which the most used method was struvite precipitation and biochar adsorption. Subsequently, evaluation is also essential, including the economic benefits and environmental impacts of the recycling process by life cycle assessment and substance flow analysis, as well as the agronomic efficiency of the recycled products. New directions for technological innovation in recycling P from livestock manure and potential risks in the recycling process are explored. The results of this study may provide a framework for understanding the mechanisms of P utilization in livestock manure, and support the overall popularization of P recycling technology from livestock manure.

Comparison of phosphorus species in livestock manure and digestate by different detection techniques

Phosphorus (P) species characterize the effectiveness of the P fertilizer. In this study, the P species and distribution in different manures (pig manure, dairy manure and chicken manure) and their digestate were systematically investigated through combined characterization methods of Hedley fractionation (H₂OP, NaHCO₃-P, NaOH-P, HCl-P, and Residual), X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) techniques. The results from Hedley fractionation showed that >80 % of P in the digestate was inorganic and the HCl-P content in manure increased significantly during anaerobic digestion (AD). XRD manifested that insoluble hydroxyapatite and struvite belonging to HCl-P were presented during AD, which was in agreement with the result of Hedley fractionation. ³¹P NMR spectral analysis revealed that some orthophosphate monoesters were hydrolyzed during AD, meanwhile the orthophosphate diester organic phosphorus like DNA and phospholipids content has increased. After characterizing P species by combining these methods, it was found that chemical sequential extraction could be an effective way to fully understand the P in livestock manure and digestate, with other methods used as auxiliary tool depending on the purpose of studies. Meanwhile, this study provided a basic knowledge of utilizing digestate as P fertilizer and minimizing the risk of P loss from livestock manure. Overall, applying digestates can minimize the risk of P loss from directly applied livestock manure while satisfying plant demands, and is an environmentally friendly P fertilizer.

[Clinical features and management analysis of 11 cases of laryngocele]

Objective: To summarize clinical features and our experience of the diagnosis and treatment of laryngocele. Methods: Clinical data of 11 laryngocele patients in department of Otorhinolaryngology Head and Neck Surgery of the Second Affiliated Hospital of Shanxi Medical University from January 2012 to December 2021 were retrospectively reviewed, including 9 men and 2 women, aged from 12 to 75 years, with median age of 56 years. Electronic laryngoscope was performed in 10 of all patients, laryngeal CT in 10 and cervical color ultrasound in 5 before operation.All the operations were performed under general anesthesia, and the external cervical approach was used for external and combined laryngocele. The internal laryngocele was resected by low temperature plasma through transoral endoscopy. Patients were followed up regularly after operation to evaluate the effect. Clinical feature, types of lesions, imaging findings, surgical approaches and follow-up results were analyzed through descriptive statistical method. Results: Eleven laryngocele patients were divided into mixed type (n=6), internal type (n=4) and external type (n=1).Nine patients presented with hoarseness or dysphonia, 7 with cervical mass and 1 with airway obstruction. Surgical resections were done through external cervical approach (n=7)or transoral endoscopic approach (n=4). All the operations were successful and no complication occurred. All cases were followed up from 17 to 110 months. No recurrence was encountered. Conclusions: Laryngocele is a rare lesion with atypical clinical presentation. Preoperative imaging including CT scan and electronic laryngoscope is essential to evaluate the location, and extent of the lesion, and to make the surgical plan.Complete surgical excision is required. Surgical resection is the only effective method for the treatment of laryngocele.

Two-step anaerobic digestion of rice straw with nanobubble water

Lignocellulose usually requires pretreatment to improve biogas production. To enhance lignocellulose biodegradability and improve anaerobic digestion (AD) efficiency, different types (N₂, CO₂, and O₂) of nanobubble water (NW) were applied in this study as soaking agent and AD accelerant to increase the biogas yield of rice straw. The results showed that the cumulative methane yields of treating with NW in two-step AD increased by 11.0%-21.4% compared with untreated straw. The maximum cumulative methane yield was 313.9±1.7 mL/gVS in straw treated with CO₂-NW as soaking agent and AD accelerant (P_CO2-M_CO2). The application of CO₂-NW and O₂-NW as AD accelerants increased bacterial diversity and relative abundance of Methanosaeta. This study suggested that using NW could enhance soaking pretreatment and methane production of rice straw in two-step AD; however, combined treatment with inoculum and NW or microbubble water in the pretreatment needs to compare in future.

[Predictive value of the proportion of hibernating myocardium in total perfusion defect on reverse remodeling in patients with HFrEF underwent coronary artery bypass graft]

Objective: To evaluate the predictive value of the proportion of hibernating myocardium (HM) in total perfusion defect (TPD) on reverse left ventricle remodeling (RR) after coronary artery bypass graft (CABG) in patients with heart failure with reduced ejection fraction (HFrEF) by ^99mTc-methoxyisobutylisonitrile (MIBI) single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) combined with ¹⁸F-flurodeoxyglucose (FDG) gated myocardial imaging positron emission computed tomography (PET). Methods: Inpatients diagnosed with HFrEF at the Cardiac Surgery Center, Anzhen Hospital of Capital Medical University from January 2016 to January 2022 were prospectively recruited. MPI combined with ¹⁸F-FDG gated PET was performed before surgery for viability assessment and the patients received follow-up MPI and ¹⁸F-FDG gated PET at different stages (3-12 months) after surgery. Δ indicated changes (post-pre). Left ventricular end-systolic volume (ESV) reduced at least 10% was defined as RR, patients were divided into reverse remodeling (RR+) group and the non-reverse group (RR-). Binary logistic regression analysis was used to identify predictors of RR. Receiver operating characteristic (ROC) curve analysis was performed and the area under the curve (AUC) was calculated to assess the cut-off value for predicting RR. Additionally, we retrospectively enrolled inpatients with HFrEF at the Cardiac Surgery Center, Anzhen Hospital of Capital Medical University from January 2021 to January 2022 as the validation group, who underwent MPI and ¹⁸F-FDG gated PET before surgery. Echocardiography was performed before CABG and after CABG (3-12 months). In the validation group, the reliability of obtaining the cut-off value for the ROC curve was verified. Results: A total of 28 patients with HFrEF (26 males; age (56.9±8.7) years) were included in the prospective cohort. HM/TPD was significantly higher in the RR+ group than in the RR- group ((51.8%±17.9%) vs. (35.7%±13.9%), P=0.016). Binary logistic regression analysis revealed that HM/TPD was an independent predictor of RR (Odds ratio=1.073, 95% Confidence interval: 1.005-1.145, P=0.035). ROC curve analysis revealed that HM/TPD=38.3% yielded the highest sensitivity, specificity, and accuracy (all 75%) for predicting RR and the AUC was 0.786 (P=0.011). Meanwhile, a total of 100 patients with HFrEF (90 males; age (59.7±9.6) years) were included in the validation group. In the validation group, HM/TPD=38.3% predicted RR in HFrEF patients after CABG with the highest sensitivity, specificity and accuracy (82%, 60% and 73% respectively). Compared with the HFrEF patients in the HM/TPD<38.3% group (n=36), RR and cardiac function improved more significantly in the HM/TPD≥38.3% group (n=64) (all P<0.05). Conclusions: Preoperative HM/TPD ratio is an independent factor for predicting RR in patients with HFrEF after CABG, and HM/TPD≥38.3% can accurately predict RR and the improvement of cardiac function after CABG.

A large cathode surface area promotes electromethanogenesis at a proper external voltage in a single coaxial microbial electrolysis cell

Microbial electrolysis cell coupled with anaerobic digestion (MEC-AD) is currently encountering constraints on electromethanogenesis. The electrode configuration modification can be a simple yet efficient way to improve electromethanogenesis. This study evaluated two coaxial electrode configurations (large anode and small cathode: A₁₀C₁; small anode and large cathode: A₁C₁₀) using carbon felt as the electrode material. At an external voltage of 1.7 V, CH₄ content was found exclusively higher in A₁C₁₀ (11 % and 13 % higher for acetate-fed and cow manure-fed, respectively) than that of the control reactors. Consequently, CH₄ production was 13 % and 29 % higher in acetate-fed and CM-fed A₁C₁₀, respectively. The strengthened electromethanogenesis was attributed to the enrichment of interspecies hydrogen transfer microbes (i.e., Mesotoga and Bathyarchaeia). The coaxial configuration with a large cathode surface area demonstrated a viable stereotype in MEC-AD for improved waste treatment and energy recovery.

Carbon footprint of dairy manure management chains in response to nutrient recovery by aerobic pre-treatment

Aerobic pre-treatment of liquid dairy manure has previously been reported as an effective nutrient export and emissions mitigation approach. The first objective of this study was to experimentally determine the optimal intermittent aeration ratio for nutrient recovery from liquid dairy manure through an on-site pilot-scale reactor to partially reduce the required energy for the aerobic process. The second objective was to theoretically investigate the total carbon footprints of direct manure spreading on croplands and permanent manure storage in open anaerobic lagoons in response to nutrient removal by the optimal determined intermittent aerobic treatment ratio. Four scenarios (S) were included; S1 was the traditional scenario of manure spread on croplands without the aerobic pre-treatment, S2 was the modified scenario of manure spread on croplands that included the aerobic pre-treatment, S3 was the traditional scenario of manure storage in lagoons, and S4 was the modified scenario of manure storage in lagoons that included the aerobic pre-treatment. The results showed that comparable nutrient removal efficiencies could be obtained with a 5:1 intermittent aeration ratio. Total nitrogen (TN) and total phosphorus (TP) were recovered were 41.5 ± 1.3% and 37.0 ± 4.0%, respectively, in ammonium sulfate and phosphorus-rich sludge, while 55.3 ± 1.4% of the chemical oxygen demand (COD) was removed. The estimated total carbon footprint for S1, S2, S3, and S4 were 24.4, 37.9, 45.3, and 45.9 kg _CO2-eqton^-1, respectively. However, the total carbon footprint of S2' and S4', which used renewable-based energy to run the reactor instead of fossil-based energy used in S2 and S4, were estimated to 29.5 and 37.5 kg _CO2-eqton^-1, respectively. Clearly, applying the aerobic pre-treatment increased the total carbon footprint of all cases except S4', in which the total carbon footprint was mitigated by -17.2%. Accordingly, the aerobic pre-treatment is only recommended in the case of S4' from a carbon footprint point of view although it is an effective nutrient recovery technology.

Removal performance and inhibitory effects of combined tetracycline, oxytetracycline, sulfadiazine, and norfloxacin on anaerobic digestion process treating swine manure

Combined veterinary antibiotics (CVAs) belonging to different antibiotics classes could cause exacerbated impacts on the anaerobic digestion (AD) process of swine manure. Four different antibiotics "two tetracyclines: tetracycline (TC) and oxytetracycline (OTC), one fluoroquinolones: norfloxacin (Norf), and one sulfonamides: sulfadiazine (SDZ)" were combined to evaluate their removal performances and its inhibition effects on AD. Results indicated that CVAs removal decreased from 84.3 to 63.7 %, with an increase in the initial concentration from 12.5 to 50 mg L^-1, where the removal of CVAs occurring in the order OTC > TC > Norf > SDZ. An average of 9.5, 7.5, 9.5, and 32.1 % of the spiked TC, OTC, SDZ, and Norf were remained in the sludge, respectively. With 50 mg L^-1 of CVAs, a competitive adsorption phenomenon was found to have a notable impact on biodegradation microorganisms' activity leading a 73.1 % decrease in CH₄ production. CVAs caused a temporal inhibition to the acidogenic activity followed by partial inhibition to methanogenic by 66.8 %, and IC₅₀ was 38.5 mg L^-1. Moreover, CVAs resulted in acetate accumulation, while 26 % and 48 % lower in TS and COD removal, respectively, were observed. A significant reduction in the relative abundance of bacteria and archaeal genera was also mentioned. The findings of this research would provide a more in-depth understanding of AD's performance in treating swine manure contaminated with combined antibiotics.

The efforts of China to combat air pollution during the period of 2015-2018: A case study assessing the environmental, health and economic benefits in the Beijing-Tianjin-Hebei and surrounding "2 + 26" regions

During the period of 2015-2018, Chinese government had made great efforts to mitigate air pollutants, such as air quality monitoring, energy structure adjustment, and pollutant emission reduction from industry, transportation and household sectors. With the special investment of 152 billion Chinese Yuan (CNY) in the Beijing-Tianjin-Hebei (BTH) and surrounding "2 + 26" regions, the annual local concentrations of PM_2.5, PM₁₀, SO₂ and NO₂ decreased from 77, 132, 38 and 46 μg/m³ to 60, 109, 20 and 43 μg/m³. It was estimated that the improvement in air quality avoided 27,021 (95 % CIs 12,548-39,738) premature deaths attributed to air pollution exposure based on an exposure-response function, including 45 %, 17 % and 15 % of cardiopulmonary, lung cancer and respiratory morality cases. Air pollution reduction was also effective in reducing work time loss, which reduced the total working time loss by 3.8 × 10⁷ (95 % CIs 1.8 × 10⁷-5.6 × 10⁷) h, and the per capita working time loss by 0.28 (95 % CIs 0.13-0.41) h/capita by 2018. From the economic aspect, air pollution control actions in those regions saved 95.6 (95 % CIs 44.2-141) billion CNY economic loss by using the value of statistical life (VSL). The total benefit-cost ratio was 63.7 % (95 % CIs 29.4 %-93.7 %). The cost-effectiveness in Beijing and Tianjin were relatively low due to the regional contribution from other cities of the air pollution transmission channel. Despite the uncertainties, the results clearly show the significance of the environmental, health and economic benefits of actions in the BTH and surrounding "2 + 26" regions for combating air pollution.

Recent advancement in conjugated polymers based photocatalytic technology for air pollutants abatement: Cases of CO2, NOx, and VOCs

According to World Health Organization (WHO) survey, air pollution has become the major reason of several fatal diseases, which had led to the death of 7 million peoples around the globe. The 9 people out of 10 breathe air, which exceeds WHO recommendations. Several strategies are in practice to reduce the emission of pollutants into the air, and also strict industrial, scientific, and health recommendations to use sustainable green technologies to reduce the emission of contaminants into the air. Photocatalysis technology recently has been raised as a green technology to be in practice towards the removal of air pollutants. The scientific community has passed a long pathway to develop such technology from the material, and reactor points of view. Many classes of photoactive materials have been suggested to achieve such a target. In this context, the contribution of conjugated polymers (CPs), and their modification with some common inorganic semiconductors as novel photocatalysts, has never been addressed in literature till now for said application, and is critically evaluated in this review. As we know that CPs have unique characteristics compared to inorganic semiconductors, because of their conductivity, excellent light response, good sorption ability, better redox charge generation, and separation along with a delocalized π-electrons system. The advances in photocatalytic removal/reduction of three primary air-polluting compounds such as CO₂, NO_X, and VOCs using CPs based photocatalysts are discussed in detail. Furthermore, the synergetic effects, obtained in CPs after combining with inorganic semiconductors are also comprehensively summarized in this review. However, such a combined system, on to better charges generation and separation, may make the Adsorb & Shuttle process into action, wherein, CPs may play the sorbing area. And, we hope that, the critical discussion on the further enhancement of photoactivity and future recommendations will open the doors for up-to-date technology transfer in modern research.

Response of phosphorus speciation to organic loading rates and temperatures during anaerobic co-digestion of animal manures and wheat straw

The world is facing huge phosphate (P) shortage and anaerobic digestion (AD) is a recognized technology to promote nutrient (N and P) recycling. The composition of P speciation in the digestate is essential for the fertilizing effect. However, how P speciation in the digestates interacts with the AD process conditions is unknown. Therefore, interaction of P speciation in digestates with AD process conditions was investigated by using a chemical sequential extraction method (Hedley fractionation) and X-ray diffraction; specifically, the effects of organic loading rate (OLR), temperature, and substrate composition were investigated. The results showed that OLR and feedstock affected P speciation in the digestate significantly due to different ion species and ionic strengths. The H₂O-P concentration in chicken manure with straw (CMS) and dairy manure with straw (DMS) digestates decreased by 44.04-48.76% and 48.88-50.49%, respectively, as the OLR increased from 2 to 4 kg VS m^-3 d^-1. Simultaneously, HCl-P increased by 38.02-44.01% in the CMS digestates due to Ca-P and Mg-P formation, indicating that Ca-P and Mg-P formation was positively correlated with OLR, whereas P mobility decreased. Further, thermophilic temperature conditions were more conducive for the formation of insoluble P than mesophilic temperature conditions in the digestates due to the thermodynamic driving force of the reactions. The results would facilitate the understanding of P transformation in the AD process under the influence of feedstock, OLR, and temperature. From the viewpoint of nutrient management, lower OLR and temperature are more beneficial for a fast P availability, whereas higher OLR and temperature are more helpful for storage and export because of P precipitated into solid phase of digestate.

Comparative evaluation of thermal and emission performances for improved commercial coal-fired stoves in China

The extensive use of traditional cooking stoves to meet daily cooking and heating requirements has highlighted the serious problem of indoor and outdoor air pollution. This study evaluates seven improved coal-fired space-heating and cooking stoves and compares them with a widely used stove of an older design, selected as a baseline reference. The seven stoves were selected from a range of candidate improved stoves submitted by manufacturers for testing as part of the air quality improvement in the Hebei Clean Air Project, Hebei Province, China. Stove performance was evaluated when burning raw coal and coal briquettes during the high and low power stages respectively. All seven improved cooking stoves surpassed the baseline stove in combined heating and cooking thermal and emission performance. Among the improved cooking stoves, Model 2-TL was found to have the highest average thermal efficiency, 87.2 ± 0.5%, when burning coal briquettes at high and low power. The lowest emission of PM2.5 was 0.94 ± 0.5 mg MJNET -1, CO 0.55 ± 0.28 g MJNET -1, and CO/CO2 1.1 ± 0.6%, respectively. It is concluded that the use of these improved heating and cooking stoves should be promoted for daily cooking and heating requirements. This strategy will not only save fuel to the benefit of the household, but widespread adoption could contribute to significant reductions of CO and PM2.5 emissions in Hebei Province.

[Comparison of off-pump coronary artery bypass grafting alone or combined with mitral valve plasty for coronary heart disease with moderate ischemic mitral insufficiency]

Objective: To compare the efficacy of off-pump coronary artery bypass grafting (CABG) or CABG plus mitral valve plasty (MVP) in patients with coronary heart disease complicated with moderate ischemic mitral insufficiency. Methods: The clinical data of 1 050 patients with coronary heart disease complicated with moderate ischemic mitral insufficiency who underwent surgical procedures from January 2009 to December 2020 were analyzed retrospectively. There were 733 males and 317 females, aging (63.3±9.0) years (range: 31 to 83 years). Patients were divided into CABG+MVP group and CABG group according to surgical methods, and the two groups of patients were matched for 1∶4 by the propensity score matching method. There were 107 patients in the CABG+MVP group and 406 patients in the CABG group after matching. The t test, Mann-Whitney U test, χ2 test, Fisher's exact probability method and repeated measures anova were used to compare the surgical outcomes and overall survival in the two groups. Results: There were no significant differences in perioperative death and postoperative complications between the two groups (all P>0.05). Compared with CABG group, CABG+MVP group had longer operation time ((5.6±1.2) hours vs. (4.2±1.0) hours, t=11.528, P<0.01), ICU stay(M(IQR))(43.0(47.3) hours vs. 25.0(33.6) hours, Z=2.483, P=0.013), and postoperative hospital stay (8(4) days vs. 7(5) days, Z=2.143, P=0.032). The amount of erythrocyte and platelet used in CABG+MVP group was significantly increased (2.0(6.5) U vs. 0(2.0) U, Z=7.084, P<0.01; 0(0.5) U vs. 0(0) U, Z=5.210, P<0.01). A total of 463 cases (93.9%) were followed up. Median follow-up was 32(31) months (range: 3 to 105 months). There was no significant difference in overall survival and no major adverse cardic and cerebrovascular events survival between CABG group and CABG+MVP group (P=0.196,P=0.305). Echocardiography showed that there was no significant difference in ejection fraction left ventricular end-diastolic diameter between the two groups (F=0.322, P=0.571; F=0.681, P=0.410). However, CABG+MVP improved mitral regurgitation better than CABG (F=160.222, P<0.01). Conclusions: For patients with coronary heart disease with moderate ischemic mitral insufficiency, the rates of all-cause mortality and major adverse cardiac and cerebrovascular events are similar between the two surgeries. Although CABG+MVP improves mitral regurgitation better than CABG, it increases the duration of surgery, ICU stay, postoperative hospital stay, and blood transfusion requirement.

[Death-related risk factors analysis of surgical treatment of myocardial infarction combined with ventricular septal rupture]

Objective: To in vestigate the death-related risk factors of surgical treatment of myocardial infarction (MI) combined with ventricular septal rupture (VSR). Methods: The clinical data of patients (68 cases) with ventricular septal rupture after myocardial infarction (PI-VSR) from January 2008 to December 2020 in Beijing Anzhen Hospital were retrospectively selected and analyzed. We followed up the surviving patients and divided them into the survival group and the death group according to the perioperative and follow-up results. The univariate analysis was performed on various indicators, and the Cox regression analysis was used to analyze the risk factors related to postoperative death. Results: A total of 68 patients (42 were male and 26 were female, with age 44-82 (64.3±8.2) years after surgical treatment of myocardial infarction combined with ventricular septal rupture were enrolled, 9 patients died during the perioperative period, 59 surviving patients were followed up for 0.1-10.5 years(mean, 4 years), and 7 deaths during follow-up. Based on this, 52 patients were selected as the survival group while 16 patients as the death group. The results of univariate analysis showed that age, VSR to operation time less than 7 days, killip grade ≥ grade 3, cardiogenic shock, preoperative use of IABP, emergent surgery were related to postoperative death. The factors with P<0.2 factors in univariate analysis were selected into the multivariate Cox regression analysis. Age ([OR=1.110(1.012-1.217), P=0.026], platelet count [OR=0.990(0.981-0.999), P=0.031], D dimer (OR=1.002[1.001-1.003], P=0.003), cardiogenic shock (OR=6.084[1.729-21.405], P=0.005) were independent risk factors for postoperative death. All patients were followed up, the survival rate of 2-year, 4-year, 6-year, 8-year, and 10-year was 77.5%, 77.5%, 71.0%, 71.0%, and 71.0%, respectively. Conclusions: Age, platelet count, D-dimer, and cardiogenic shock are risk factors for death after surgical treatment of myocardial infarction combined with ventricular septal rupture. Surgery is an effective method for the treatment of myocardial infarction combined with ventricular septal rupture. Long-term prognosis of the surviving patients during perioperative are relatively better.

Balancing acidogenesis and methanogenesis metabolism in thermophilic anaerobic digestion of food waste under a high loading rate

Achieving a metabolic balance between volatile fatty acid (VFA) production and conversion is a standing challenge in high temperature and organic loading rate anaerobic digestion. A thermophilic anaerobic digestion reactor fed with food waste was therefore operated for 230 days to investigate metabolic performance in acidogenesis and methanogenesis. Results showed a methane yield of 310 mL/g·COD under an organic loading rate (OLR) of 10.0 kg·COD/(m³·d). The VFA concentration of 110 mg/L was low, indicating well-balanced VFA production and conversion metabolism. Highly specific acetic acid and propionic acid methanogenic activity showed satisfactory metabolic capability. Methanosarcina (95.2%) predominated in the high OLR state and increased abundance of Methanothermobactger (4.2%) was also observed. Syntrophic acetic acid oxidation bacterial was not found in different HRT conditions. It is therefore reasonable to speculate cleavage of acetic acid by mixotrophic Methanosarcina. Good acidogenesis and methanogenesis balance promote stable thermophilic AD of food waste under a high OLR.

[m7G-lncRNAs are potential biomarkers for prognosis and tumor microenvironment in patients with colon cancer]

OBJECTIVE

To assess the value of m⁷G-lncRNAs in predicting the prognosis and microenvironment of colorectal cancer (CRC).

METHODS

We screened m⁷G-lncRNAs from TCGA to construct an m⁷G-lncRNAs risk model using multivariate Cox analysis, which was validated using ROC and C-index curves. Calibration and nomogram were used to predict the prognosis of CRC patients. Point-bar charts and K-M survival curves were used to assess the correlation of risk scores with the patients' clinical staging and prognosis. CIBERSORT and ESTIMATE were used to explore the association between the tumor microenvironment and immune cell infiltration in patients in high and low risk groups and the correlation of risk scores with microsatellite instability, stem cell index and immune checkpoint expression. A protein-protein interaction network was constructed, and the key targets regulated by m⁷G-lncRNAs were identified and validated in paired samples of CRC and adjacent tissues by immunoblotting.

RESULTS

We identified a total of 1722 m⁷G-lncRNAs from TCGA database, from which 12 lncRNAs were screened to construct the risk model. The AUCs of the risk model for predicting survival outcomes at 1, 3 and 5 years were 0.727, 0.747 and 0.794, respectively. The AUC of the nomogram for predicting prognosis was 0.794, and the predicted results were consistent with actual survival outcomes of the patients. The patients in the high-risk group showed more advanced tumor stages and a greater likelihood of high microsatellite instability than those in the low-risk group (P < 0.05). The tumor stemness index was negatively correlated with the risk score (r=-0.19; P=7.3e-05). Patients in the high-risk group had higher stromal cell scores (P=0.0028) and higher total scores (P=0.007) with lowered expressions of activated mast cells (r=-0.11; P=0.045) and resting CD4+ T cells (r=-0.14; P=0.01) and increased expressions of most immune checkpoints (P < 0.05). ATXN2 (P= 0.006) and G3BP1 (P=0.007) were identified as the key targets regulated by m⁷G-lncRNAs, and their expressions were both higher in CRC than in adjacent tissues.

CONCLUSION

The risk model based on 12 m⁷G-lncRNAs has important prognostic value for CRC and can reflect the microenvironment and the efficacy of immunotherapy in the patients.

Enhancing pathogen inactivation in pig manure by introducing thermophilic and hyperthermophilic hygienization in a two-stage anaerobic digestion process

Conventional mesophilic anaerobic digestion (AD) is widely used to treat animal manure, but pathogen inactivation remains a significant challenge. Thermophilic and hyperthermophilic hydrolysis pretreatment was thus introduced as a hygienization step in a two-stage anaerobic digestion process. Results from 100-day experiments showed culturable Escherichia coli (E. coli) reduction was up to 6.9 log₁₀ through a hygienization step, but RT-qPCR tests showed much less reduction in viable E. coli. The difference between viable and culturable cells revealed the complexity in pathogen inactivation. High-throughput sequencing indicated that the second stage in the two-stage AD further reduced the relative abundance of pathogens, including Enterococcus, Streptococcus, and Acinetobacter, while Clostridium_sensu_stricto still exhibited high relative abundance. Thermophilic hygienization induced a 6.7% increment in methane production, while hyperthermophilic pretreatment showed minimal effect on methane production. Focusing on the energy recovery and environmental safety point of view, the introduction of an integrated system incorporating the thermophilic and two-stage anaerobic process is recommended.

Predicting membrane fouling in a high solid AnMBR treating OFMSW leachate through a genetic algorithm and the optimization of a BP neural network model

Anaerobic membrane bioreactors are a promising technology in the treatment of high-strength wastewater; however, unpredictable membrane fouling largely limits their scale-up application. This study, therefore, adopted a backpropagation neural network model to predict the membrane filtration performance in a submerged system, which treats leachate from the organic fraction of municipal solid waste. Duration time, water yield flow, influent COD, pH, bulk sludge concentration, and the ratio of ΔTMP to filtration time were selected as input variables to simulate membrane permeability. The membrane pressure slightly increased by 1.1 kPa within 62 days of operation. The results showed that the AnMBR membrane filtration performance was acceptable when treating OFMSW leachate under a flux of 6 L/(m²·h). The model results indicated that the sludge concentration largely determined the membrane fouling with a contribution of 33.8%. Given the local minimization problem in the BP neural network process, a genetic algorithm was introduced to optimize the simulation process, and the relative error of the results was reduced from 5.57% to 3.57%. Conclusively, the artificial neural network could be a useful tool for the prediction of an AnMBR that is so far under development.

Mitigating membrane fouling in a high solid food waste thermophilic anaerobic membrane bioreactor by incorporating fixed bed bio-carriers

Hybrid anaerobic membrane bioreactor (Hy-AnMBR) was developed by incorporating polyurethane sponge carriers to mitigate membrane fouling. The results showed that the membrane fouling was well controlled in Hy-AnMBR from the aspects of sludge property and membrane filtration performance. The solid concentration, including TS and MLSS in the Hy-AnMBR was reduced after introducing the fixed bed carrier, which was 13% and 20% lower than the control AnMBR (Con-AnMBR), and this resulted in improved filtration performance. The scanning electron microscope (SEM) photograph showed that membrane pores could still be observed on the Hy-AnMBR surface, indicating that the cake layer fouling of the Hy-AnMBR was less than the Con-AnMBR. The increase of the EPS and SMP promoted the acceleration of the membrane fouling rate. Analysis through confocal laser scanning microscopy (CLSM) and membrane cleaning revealed that adding sponge carriers mitigated 3.3%-9% pore-blocking, and the total membrane resistance in the Hy-AnMBR was reduced by 52% compared to the Con-AnMBR. Chemical cleaning was essential for pollutant removal, and membrane permeability recovery was more than 97%.

Selecting the optimal nutrients recovery application for a biogas slurry based on its characteristics and the local environmental conditions: A critical review

Digestate (effluent of biogas plants) became the main bottleneck for biogas industry expansion because it often exceeds the capacity of surrounding croplands as fertilizer. Nutrients recovery from digestate is a promising solution for closing nutrients cycles and generating high value-added byproducts. In fact, numerous nutrients recovery technologies were reported and utilized for that purpose. However, each technology has optimum working conditions, while digestates have different characteristics due to the different substrates, digestion conditions, and handling methods. On the other hand, no protocol has been reported yet for selecting the optimal nutrients recovery technology or sequenced technologies for different digestates regarding their characteristics and the surrounding environmental conditions. In this study, an interactive flowchart was suggested and discussed for selecting the most appropriate technology or sequential techniques among the different alternatives. The whole digestate utilization technologies, solid-liquid separation technologies, liquid and solid processing technologies were included.

Nano agrochemical zinc oxide influences microbial activity, carbon, and nitrogen cycling of applied manures in the soil-plant system

The widespread use of nano-enabled agrochemicals in agriculture for remediating soil and improving nutrient use efficiency of organic and chemical fertilizers is increasing continuously with limited understanding on their potential risks. Recent studies suggested that nanoparticles (NPs) are harmful to soil organisms and their stimulated nutrient cycling in agriculture. However, their toxic effects under natural input farming systems are just at its infancy. Here, we aimed to examine the harmful effects of nano-agrochemical zinc oxide (ZnONPs) to poultry (PM) and farmyard manure (FYM) C and N cycling in soil-plant systems. These manures enhanced microbial counts, CO₂ emission, N mineralization, spinach yield and N recovery than control (unfertilized). Soil applied ZnONPs increased labile Zn in microbial biomass, conferring its consumption and thereby reduced the colony-forming bacterial and fungal units. Such effects resulted in decreasing CO₂ emitted from PM and FYM by 39 and 43%, respectively. Further, mineralization of organic N was reduced from FYM by 32%, and PM by 26%. This process has considerably decreased the soil mineral N content from both manure types and thereby spinach yield and plant N recoveries. In the ZnONPs amended soil, only about 23% of the applied total N from FYM and 31% from PM was ended up in plants, whereas the respective fractions in the absence of ZnONPs were 33 and 53%. Hence, toxicity of ZnONPs should be taken into account when recommending its use in agriculture for enhancing nutrient utilization efficiency of fertilizers or soil remediation purposes.

Challenges of pathogen inactivation in animal manure through anaerobic digestion: a short review

Animal manure is the main source of bioenergy production by anaerobic digestion (AD). However, the pathogenic bacteria in manure may pose a high risk to human health by contaminating the environment if not effectively inactivated during AD. Worldwide, more than 20,000 biogas plants are running for the treatment of animal manure. AD has been playing the important role in establishing a circular economy in the agricultural sector and may contribute to the United Nations sustainable development goal (UN SDG). Nevertheless, whether AD is a reliable approach for pathogens inactivation has been challenged. A comprehensive understanding of the coping mechanisms of pathogens with adverse conditions and the challenges of establishing the AD process to inactivate effectively pathogens are yet to be analyzed. In this review, the diversity and resistance of pathogens in animal manure are summarized. The efficiencies and the difficulties of their inactivations in AD are also analyzed. In particular, three forms of pathogens i.e. sporing-forming pathogens, viable but non-culturable (VBNC) pathogens, and persistent pathogens are discussed. The factors influencing the pathogens’ inactivation and AD efficiencies are analyzed. The trade-off between energy production and pathogens inactivation in an AD system was consequently pointed out. This review concluded that the development of anaerobic processes should meet the goals of high efficient bioenergy production and deep hygienization.

Revealing the link between evolution of electron transfer capacity of humic acid and key enzyme activities during anaerobic digestion

Humic acid (HA) is an important active compound formed during anaerobic digestion process, with a complex structure and dynamic electron transfer capacity (ETC). However, the mechanisms by which these macromolecular organic compounds dynamically interact with the microbial anaerobic digestion process at different operating temperatures are still unclear. In this study, the link between the evolution of the ETC of HAs and the microbial community under mesophilic and thermophilic conditions was investigated. The results showed an increasing trend in the ETC of HAs in both mesophilic (671-1479 μmol gHA^-1) and thermophilic (774-1506 μmol gHA^-1) anaerobic digestion (AD) until day 25. The ETC was positively correlated with the bacterial community of hydrolytic and acidogenic phases, but negatively correlated with the archaeal community of the methanogenic phase. Furthermore, the relationship between ETC and key enzyme activity was explored using a co-occurrence network analysis. HAs revealed a high potential to promote key enzyme activities during hydrolysis (amylase and protease) and acidification (acetate kinase, butyrate kinase, and phosphotransacetylase) while inhibiting the key enzyme activity in the methanogenic phase during the anaerobic digestion process. Moreover, HAs formed under thermophilic conditions had a greater influence on key enzyme activities than those formed under mesophilic conditions. This study advances our understanding of the mechanisms underlying the influence of HAs on anaerobic digestion performance.

Ensiling process for efficient biogas production from lignocellulosic substrates: Methods, mechanisms, and measures

Ensiling has been developed as mainstream technologies to preserve lignocellulose biomass for biogas production. However, the lack of general evaluation methods and process mechanism research hinders the understanding of its effectiveness. In this context, we reviewed existing studies and proposed some key considerations: (1) For assessing the ensiling process, determined dry matter contents should be corrected according to the volatilization loss in oven-drying method to obtain accurate storage loss and methane yield; (2) For comprehensive assessments, the trade-off between storage loss and enhanced biomethane yield should be evaluated from the entire-chain process; (3) The mechanism to enhance methane yield is primarily attributed to increased lignocellulosic biodigestibility through acid-based hydrolysis and biological degradation during ensiling; (4) Measures including co-storage, increasing buffering capacity, adjusting carbon/nitrogen ratio, and additives can be adopted to increase biogas production. The proposed methods, mechanisms, and measures (3Ms) could help initiate the specific quality criteria of biogas-oriented silages.

Enhancing the performance of thermophilic anaerobic digestion of food waste by introducing a hybrid anaerobic membrane bioreactor

The thermophilic anaerobic digestion of food waste was a long-term challenge for maintaining process stability. A hybrid submerged anaerobic membrane bioreactor (AnMBR), integrating 27%(v/v) polyurethane sponge as fixed carriers were therefore investigated at (50 ± 2) °C. The organics removal efficiencies, COD mass balance, and membrane filtration performance were investigated in a 75-days continuously operated experiment. The results showed that methane production reached 0.31 L/(kg·COD) under an organic loading rate of 7.3 kg·COD/(m³·d). The low concentration of total volatile fatty acids of 247 ~ 274 mg/L and a high proportion of Methanosarcina (>97%) represented the high stability of the thermophilic process. Approximately 21% of biomass grew on the carriers in the hybrid AnMBR and induced a much lower suspended solids concentration and viscosity of bulk sludge. Noticeable lower trans-membrane pressure was consequently observed. The affecting factors identified by PCA analysis proved the advantages of the hybrid AnMBR for alleviating membrane fouling formation.

Determination of Tetracycline, Oxytetracycline, Sulfadiazine, Norfloxacin, and Enrofloxacin in Swine Manure Using a Coupled Method of On-Line Solid-Phase Extraction with the UHPLC-DAD

The use of various veterinary antibiotics (VAs) in animal husbandry raises serious concerns about the development of antibiotic resistance. Antibiotics such as tetracycline, oxytetracycline, sulfadiazine, norfloxacin, and enrofloxacin are the most frequently used antimicrobial compounds in animal husbandry and generate large eco-toxicological effects; however, they are still difficult to determine in a complex matrix such as swine manure. This study has developed an effective method for detecting five VAs in swine manure using Ultra-High-Performance Liquid Chromatography-Diode Array Detector (UHPLC-DAD) coupled with on-line solid-phase extraction (SPE). The results show that the mobile phase of ACN/0.01 M oxalic acid was the optimum at pH 3.0. VAs in a swine manure matrix were extracted using solid extraction buffer solution (T3) with 97.36% recovery. Sensitivity, accuracy, and precision were also evaluated. The validity study showed good linearity (R2 > 0.99). Limit of detection (LOD) was found to be from 0.1 to 0.42 µg mL-1 in the liquid fraction and from 0.032 to 0.58 µg g-1 dw in the solid fraction. The corresponding values of the limit of quantification (LOQ) ranged from 0.32 to 1.27 µg mL-1 for the liquid fraction and from 0.096 to 1.77 µg g-1 dw for the solid fraction. Therefore, the proposed method showed the potential applicability for detecting different antibiotic compounds from swine manure samples.

Quantitative characterization and effective inactivation of biological hazards in struvite recovered from digested poultry slurry

Struvite formed from digested poultry slurries can serve as an alternative to chemical fertilizers; however, the biological safety of such products is questionable. Therefore, quantification and inactivation of foodborne pathogens existing in struvite are important. Herein, the dynamics of foodborne pathogens' (Streptococcus faecalis, S. typhimurium, Clostridium perfringens, and Escherichia coli) living status, whether culturable and viable but non-culturable (VBNC) in struvite, were quantified for the first time. Meanwhile, inactivation technologies, namely high-humidity hot air impingement blanching (HHAIB), cold plasma, and hot air treatment, were evaluated and compared for their potential to inactivate/kill foodborne pathogens in struvite. An increase in precipitation pH from 9.0 to 11.0 decreased the culturable count of pathogens in the struvite from 75 to 86% to 7-20%, while the VBNC pathogen counts increased from 16 to 24% to 35-55%. Among the tested inactivation technologies, the HHAIB treatment at 130 °C for 120 s killed approximately 68-79% of foodborne pathogens in struvite precipitated at pH 9.0. VBNC pathogens increased from 16 to 24% to 57-68% after HHAIB treatment at 130 °C for 120 s. Struvite treatment with different inactivation technologies did not change its crystalline structure; however, it reduced functional group abundance. Therefore, further research on inactivation technologies is required to achieve better pathogen reduction efficiency in struvite to make it a biologically safe fertilizer for crop production.

[Interpretation of the American Association for Thoracic Surgery expert consensus document: coronary artery bypass grafting in patients with ischemic cardiomyopathy and heart failure in 2021]

An expert consensus on coronary artery bypass grafting (CABG) in patients with ischemic cardiomyopathy (ICM) was released by the American Association for Thoracic Surgery in May 2021, which contains a vast array of perioperative recommendations. During preoperative period, a comprehensive assessment on ICM including myocardial viability and valve function by a multi-disciplinary team (MDT) approach should be performed. In terms of intraoperative period, multiple arterial conduits and on-pump CABG using cold blood cardioplegia should be considered, meanwhile, other aspects involving concomitant management of mitral valve regurgitation and arrythmia, as well as active use of mechanical cardiac assist devices (e.g., intra-aortic balloon pump) should also be achieved. Finally, a range of postoperative interventions which includes standardized MDT management in intensive care unit (ICU), continuous use of cardiac assist devices, cardiac pacing, close follow-up within 90 days and drug treatment strictly guided by the guidelines after discharge from hospital should be conducted. The above-mentioned perioperative bundled care might reduce perioperative complications and operative mortality, and thus improve the prognosis of the patients with ICM.

Nutrients recovery from fresh liquid manure through an airlift reactor to mitigate the greenhouse gas emissions of open anaerobic lagoons

Open anaerobic lagoons are widely used for liquid manure storage and treatment, with excess greenhouse gas (GHG) and odor emissions. In this study, liquid manure was valorized through hybrid nitrogen and phosphorous recovery as value-added products using an airlift reactor. Also, the organic load of liquid manure was reduced before discharging into anaerobic lagoons, which simultaneously mitigated GHG emissions. The results showed that 14.5% of total nitrogen (TN) was recovered as ammonium sulfate, while 38.8% of TN and 79.3% of total phosphorus (TP) were recovered as phosphorus-rich sludge. After the pre-treatment in the reactor, the odor could be controlled effectively due to a 94.2% decrease in total VFAs. In addition, 59.0% of COD was removed, which decreased the theoretical modeled GHG emissions by 51.7% compared to the traditional direct discharging. The application is promising for upgrading anaerobic lagoons of liquid manure.

A review targeting veterinary antibiotics removal from livestock manure management systems and future outlook

Veterinary antibiotics (VAs) contamination has been considered as a worldwide environmental and health concern in recent decades. This paper reviewed the variability of contents of VAs and their release from the animal breeding industry into the surrounding environment along with the performance of the manure treatment technologies. The data collected revealed that VAs were mostly excreted in animal feces and observed in manure, soil, water, and sediment. The findings illustrate the disparity of VAs in excretion rates, consumption, and their residues in the environment with relatively high distribution for tetracyclines, fluoroquinolones, and sulfonamides. Anaerobic digestion has a capacity to remove of 73% VAs while manure composting and constructed wetlands can remove 84.7%, and 90% VAs. Due to the profound effect of antibiotics on the environment, further research and intensive management strategies for livestock manure need to be designed to improve the removal efficiency and manure management technologies.

Vibration modes of a transportable optical cavity

Many factors still need to be evaluated to fully understand the physical mechanisms determining optical cavity vibration, which are crucial for designing and constructing a transportable ultra-stable laser. Herein, a detailed dynamic analysis is used to characterize the vibration modes of a transportable optical cavity. The first five resonance modes are identified in the presence of a cavity support, and the guidelines to achieve a high first-order resonance frequency are proposed; thereby, high robustness is described using a 50 mm length optical cavity. The results demonstrate that the first-order resonance of up to 681 Hz with a gross weight of 2.51 kg can be achieved using an optimization strategy for given cavity support. The theoretical results are consistent with simulation and experiment. With the optimal group, a 1.34 Hz linewidth transportable ultra-stable laser at 1550 nm is established, and a linewidth of 1.5 Hz and frequency instability of 9.5×10^-15@1s are obtained after the test including 100 km actual road transportation and 34 min continuous vibration. The test condition is equivalent to ∼ 1000 km road transportation. Our method can be readily extended to other transportable optical cavities, providing a powerful tool for improving the robustness of vibration, particularly important for transportable environments.