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Study of the Activation Process of a 2 m3 Pilot Biodigester on a Microfarm Site
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作者 Jean-Baptiste Mansaly Djicknoum Diouf +4 位作者 Bruno Pirou Elhadji Mba Bamdo Diakhaby Seynabou Lo Amadou Seidou Maïga Diène Ndiaye 《Journal of Agricultural Chemistry and Environment》 2023年第4期397-413,共17页
A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université Gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 ... A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université Gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 L of bovine rumen and 145 L of cow dung, the functional parameters of the reaction medium, i.e., temperature, pH, salinity and conductimetry, were regularly monitored at a rate of 3 tests per day until the thirtieth day, corresponding to the flame test and the start of analysis and daily loading of the biodigester. The analysis of the biogas obtained after the flame test showed us the considerable contribution of bovine hindquarters to the CH4 fraction, which reached 72.2% from the start of the production phase. As anaerobic digestion is both a complex and multiparametric process, microbiological analysis revealed the presence of several strains of bacteria in the substrate used. Among the most abundant were Escherichia coli, Klebsiella spp, non-fermentative Gram-negative bacilli and Enterococcus sp. However, the bacterial strain that interests us most in anaerobic digestion is the non-fermentative Gram-negative family. We see the identification and temporal monitoring of these families of bacteria as a major step forward in the control of anaerobic fermentation processes in the Sahelian context and in Senegal in particular. 展开更多
关键词 Pilot digester Activation Bovine Belly Conductimetry SALINITY Microbiology Analysis
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Design Considerations of a Flexible Biogas Digester System for Use in Rural Communities of Developing Countries
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作者 Jerome Ndam Mungwe Derek Ajesam Asoh Edwin Mbinkar 《Journal of Sustainable Bioenergy Systems》 2021年第4期260-271,共12页
S<span>everal challenges are associated </span></span><span style="font-family:"">with</span><span style="font-family:""> the development, adoption and... S<span>everal challenges are associated </span></span><span style="font-family:"">with</span><span style="font-family:""> the development, adoption and de</span><span style="font-family:"">ployment of biogas digesters in developing countries. Amongst these challenges is a comprehensive and systematic procedure for the design of digesters suitable for rural communities. This paper proposes the Flexible Biogas Digester System (FBDS) as a viable option for rural communities in developing countries and provide</span><span style="font-family:"">s</span><span style="font-family:""> a detailed step-by-step procedure for it</span><span style="font-family:"">s</span><span style="font-family:""> design. The biogas production process is a function of the digester operating factors which may be grouped into physical, process and performance parameters. The physical design parameters include</span><span style="font-family:""> </span><span style="font-family:"">the digester volume, the volume of the biogas storage tank, and the volume of the installation pit. The process parameters include total solid content of the slurry (TS), organic loading rate (OLR), digester operating temperatures, pH of the slurry inside the digester. The performance parameters include</span><span style="font-family:""> </span><span style="font-family:"">biogas production rate, biogas productivity and biogas quality. The Net Present Value and the Levelised Cost of Energy are presented for simple economic evaluation of the FBDS. 展开更多
关键词 Flexible Biogas digester System Design Parameters Biogas in Rural Communities Biogas in Sub-Sahara Africa digester Design Factors
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Cleaner production for continuous digester processes based on hybrid Pareto genetic algorithm
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作者 JIN Fu\|jiang, WANG Hui, LI Ping (Institute of Industrial Process Control, Zhejiang University, Hangzhou 310027, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期129-135,共7页
Pulping production process produces a large amount of wastewater and pollutant emitted, which has become one of the main pollution sources in pulp and paper industry. To solve this problem, it is necessary to implemen... Pulping production process produces a large amount of wastewater and pollutant emitted, which has become one of the main pollution sources in pulp and paper industry. To solve this problem, it is necessary to implement cleaner production by using modeling and optimization technology. This paper studies the modeling and multi\|objective genetic algorithms for continuous digester process. First, model is established, in which environmental pollution and saving energy factors are considered. Then hybrid genetic algorithm based on Pareto stratum\|niche count is designed for finding near\|Pareto or Pareto optimal solutions in the problem and a new genetic evaluation and selection mechanism is proposed. Finally using the real data from a pulp mill shows the results of computer simulation. Through comparing with the practical curve of digester,this method can reduce the pollutant effectively and increase the profit while keeping the pulp quality unchanged. 展开更多
关键词 cleaner production multi\|objective optimization genetic algorithm Pareto stratum concentration of residual alkali Kamyr continuous digester
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Small-Scale Household Biogas Digesters as a Viable Option for Energy Recovery and Global Warming Mitigation--Vietnam Case Study
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作者 Thanh Ba Ho Timothy Kilgour Roberts Steven Lucas 《Journal of Agricultural Science and Technology(A)》 2015年第6期387-395,共9页
Biogas from livestock waste is considered as clean and renewable energy in Vietnam. In the last 20 years, in rural and remote areas of Vietnam, there has been a significant increase of small-scale household biogas dig... Biogas from livestock waste is considered as clean and renewable energy in Vietnam. In the last 20 years, in rural and remote areas of Vietnam, there has been a significant increase of small-scale household biogas digesters. Biogas digesters create the benefits of replacing energy and mitigation of climate change caused by greenhouse gas (GHG) emission and deforestation for firewood and charcoal. Livestock waste produces approximately 85 million tonnes every year and continues to increase, meaning there are huge feedstocks for biogas digesters to meet the energy demands in households. However, there are also many constraints on the development programme for small-scale household biogas digester. In Vietnam, the socio-economic situation and the lack of a sustainable energy policy for biogas from livestock sector are hindering the growth of the biogas digester industry. Government subsidies are needed to encourage farmers to participate. This paper will be helpful not only for the sustainable development of household biogas in Vietnam, but also for the developing program of biogas generation in developing countries with similar agricultural economies to Vietnam. 展开更多
关键词 Small-scale household biogas renewable energy biogas digester Vietnam.
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Apparatus Prototype for Purposes of Teaching in Bio-digesters
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作者 Martin Trinidad Martinez Garcia Jose Luis Magana Ramirez Rodrigo Mauricio Rodriguez Cuellar 《Journal of Chemistry and Chemical Engineering》 2014年第8期834-840,共7页
A mathematical model is developed based on a simplified mechanism of anaerobic digestion. The main objective is to quantitatively analyze the digestion process to optimize operating conditions and maintenance of this ... A mathematical model is developed based on a simplified mechanism of anaerobic digestion. The main objective is to quantitatively analyze the digestion process to optimize operating conditions and maintenance of this equipment, which could be used to test different materials and be able to apply these results to the possible scaling to bio-digesters installed in the field. The experiments were carried out in a hybrid system bio-digester photovoltaic cells. The bio-digester is made of stainless steel with dimensions to treat an average of 10 kg of raw material and produce biogas from different organic materials. The reactor has been conditioned with temperature sensors, pressure and methane gas that allow monitoring the concentration of the gas and the conditions of operation during the time of digestion. The system has a photovoltaic array to provide the energy required to keep the temperature constant, The experiment was conducted using materials such as goat manure mixed with household waste, and various formulations of these materials were prepared. The experimental results were used to test the mathematical model. 展开更多
关键词 Biodigester anaerobic digestion methane production biomass treatment.
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Dimensioning of an Anaerobic Digester for the Treatment of Chicken Manure and for the Production of Biogas: The Case Study of a Chicken Farm in Yaokokoroko (Côte d’Ivoire)
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作者 Kouakou Adjoumani Rodrigue Ehouman Ahissan Donatien +4 位作者 Konan Affoué Tindo Sylvie Teki Adjoba Marie-Emmanuelle Kouadio Marc Cyril Adou Kouakou Eric Konan Gbangbo Remis 《Green and Sustainable Chemistry》 CAS 2022年第4期91-103,共13页
This study allowed us to highlight the level of pollution of a BAYA River water near several poultry farms and the sizing of an anaerobic digester that will be able to treat chicken manure from a poultry farm (BRIN FO... This study allowed us to highlight the level of pollution of a BAYA River water near several poultry farms and the sizing of an anaerobic digester that will be able to treat chicken manure from a poultry farm (BRIN FOUNDATION). To evaluate this pollution, the parameters such as ammonium (NH<sub>4</sub><sup>+</sup>), Phosphate (PO<sub>4</sub><sup>3-</sup>), Biochemical Oxygen Demand (DBO<sub>5</sub>) and Nitrate (NO<sub>3</sub><sup>-</sup>) were determined. For sampling point P1, the concentrations in mg/L of these parameters are (25.00 ± 4.25), (0.40 ± 0.20), (98.00 ± 6.35) and (96.00 ± 5.35), respectively. On the other hand, for sampling point P2, the concentrations in mg/L of these parameters are respectively (33.00 ± 9.05), (0.70 ± 0.12), (123 ± 7.13) and (93 ± 7.10). These values indicate a strong organic pollution of the BAYA River. The determination of the different concentrations of the organic pollution parameters allowed us to evaluate the degradation and the quality of the water of the BAYA River water, by the poultry activity. However, considering the physicochemical properties of the waste (chicken manure), which is the main source of organic pollution, we have considered an energy recovery through the production of biogas. This requires the design, sizing, and implementation of an anaerobic digester in a poultry farm. Therefore, the project would require the construction of an adapted masonry type anaerobic digester with a capacity of 10 m<sup>3</sup>. 展开更多
关键词 BIOGAS Organic Pollution Surface Water Biodigester Chicken Manure Anaerobic Digestion
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Prediction of Kappa Number in Eucalyptus Kraft Pulp Continuous Digester Using the Box &Jenkins Methodology
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作者 Flávio M. Correia José V. Hallak d’Angelo +1 位作者 Roger J. Zemp Sueli A. Mingoti 《Advances in Chemical Engineering and Science》 2014年第4期539-547,共9页
The quality of the resulting pulping continuous digesters is monitored by measuring the Kappa number, which is a reference of residual lignin. The control of the kappa number is carried out mainly in the top of the di... The quality of the resulting pulping continuous digesters is monitored by measuring the Kappa number, which is a reference of residual lignin. The control of the kappa number is carried out mainly in the top of the digester, therefore it is important to get some indication of this analysis beforehand. In this context, the aim of this work was to obtain a prediction model of the kappa number in advance to the laboratory results. This paper proposes a new approach using the Box & Jenkins methodology to develop a dynamic model for predicting the kappa number from a Kamyr continuous digester from an eucalyptus Kraft pulp mill in Brazil. With a database of 1500 observations over a period of 30 days of operation, some ARMA models were studied, leading to the choice of ARMA (1, 2) as the best forecasting model. After fitting the model, we performed validation with a new set of data from 30 days of operation, achieving a model of 2.7% mean absolute percent error. 展开更多
关键词 Continuous digester KAPPA NUMBER PREDICTION Time Series BOX & Jenkins
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Performance Improvement for Sisal Waste Anaerobic Biodegradation by Digester Redesign and Feed Size Reduction
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作者 Yusufu Risasi Rajabu Samwel Victor Manyele 《Engineering(科研)》 2015年第9期553-566,共14页
This Anaerobic Digestion of Sisal decortication residue (SDR) from sisal decorication unit at Hale biogas plant in Tanga (Tanzania) is presented. The study was done to address the challenges facing Katani limited at H... This Anaerobic Digestion of Sisal decortication residue (SDR) from sisal decorication unit at Hale biogas plant in Tanga (Tanzania) is presented. The study was done to address the challenges facing Katani limited at Hale biogas plant. This plant was built as pilot before building other biogas plants. These challenges were like high retention time of substrate which was SDR, low biogas productivity, high investment costs due to large tanks sizes and low plant availability. From the study, it was discovered that, when particle size was reduced biogas production increased, degradation of SDR also increased and no significant change in biogas composition. Increase in biogas yield of 30% and 129% were recorded for reduced SDR compared to raw size SDR digested at atmospheric condition and 40°C respectivelly. SDR degradation measured in TS and VS removal efficiency, showed increase in degradation of about 5% for the reduced particle size compared to raw size particle. The study concluded that SDR was good raw material for biogas production when 90% of the particles reduced to less than 2 mm. To maximize production, digestion must be conducted at high temperature around 40°C with constant monitoring and control of all para-meters. This will increase plant availability by increasing efficiency and life span of the pumps and stirrers. 展开更多
关键词 Anaerobic DIGESTION SISAL DECORTICATION Residue BIOGAS
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Feasibility Study to Build an Anaerobic Digester Fed with Vegetables Matrices in Central Italy
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作者 Umberto Desideri Francesco Zepparelli +3 位作者 Livia Arcioni Omella Calderini Francesco Panara Matteo Todini 《Journal of Energy and Power Engineering》 2013年第6期1082-1089,共8页
The present paper assessed a feasibility study to build a small-size anaerobic digester, where a forage legume, (Alfalfa, IVledicago sativa L.), together with other crops, such as sorghum, could be used. Alfalfa is ... The present paper assessed a feasibility study to build a small-size anaerobic digester, where a forage legume, (Alfalfa, IVledicago sativa L.), together with other crops, such as sorghum, could be used. Alfalfa is a highly sustainable crop, since it can fix nitrogen, with the benefit of avoiding underground water pollution by nitrates, its residual products are rich with nitrogen, thus improving soil structure and fertility more than popular graminaceous crops such as corn, and it needs little irrigation. All these characteristics make it one of the vegetable species with the lowest energy and water needs for growing. The aims of this feasibility study are: (1) optimization of feedstock in the bio-digester; (2) typology of bio-digester; (3) size of bio-digester in relation with land availability for growing the energy crops; (4) the utilization of bio-gas produced by bio-digester as fuel in combined heat and power systems; (5) disposal of waste-water according to regional and national laws. The final aim of this study is to verify the possibility to develop an alternative economical use of marginal soils in relatively dry areas of central Italy that could be applied in other areas with similar climatic conditions. 展开更多
关键词 Anaerobic digestion ALFALFA DIGESTATE SILAGE sorghum.
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Study of the Limit of the Technological Transition in the Field of Methanisation in Senegal (from Laboratory Scale to <i>in-Situ</i>Biodigester)
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作者 Jean Baptiste Mansaly Djicknoum Diouf +2 位作者 Bruno Piriou Diène Ndiaye Amadou Seydou Maïga 《Journal of Sustainable Bioenergy Systems》 2021年第4期215-226,共12页
The</span><span style="font-family:""><span style="font-family:Verdana;"> Anaerobic digestion in Senegal is of particular interest to the scientific com</span><span ... The</span><span style="font-family:""><span style="font-family:Verdana;"> Anaerobic digestion in Senegal is of particular interest to the scientific com</span><span style="font-family:Verdana;">munity given the availability of substrates and their distributio</span><span style="font-family:Verdana;">n throughout the country. However, from a technological point of view, the existing installations seem to be obsolete, which does not allow to reproduce the results of the laboratory tests. Thus, the present study aims to take stock of the situation in relation to the studies carried out in laboratories and those concerning the actual monitoring of the bio-digesters </span><i><span style="font-family:Verdana;">in</span></i> <i><span style="font-family:Verdana;">situ</span></i><span style="font-family:Verdana;">. In fact, most experimental bio-digesters operate under optimal implementation conditions with strict control of input and output parameters. However, this is not the case for reactors installed in the field, as these so-called bio-digesters are exposed to r</span><span style="font-family:Verdana;">eal environmental conditions with a periodic variation of the phy</span><span style="font-family:Verdana;">sic-chemical parameters in the reactors throughout the day. This leads to a differential behavior of the micro-organisms, thus affecting their performance. This results in lower yields for those digesters operating under real environmental conditions. 展开更多
关键词 Digestion Anaerobic Substrate Temperature pH Inhibitory Factors
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Hybrid Donnan dialysiseelectrodialysis for efficient ammonia recovery from anaerobic digester effluent
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作者 Zhinan Dai Cong Chen +5 位作者 Yifan Li Haoquan Zhang a Jingmei Yao Mariana Rodrigues Philipp Kuntke Le Han 《Environmental Science and Ecotechnology》 SCIE 2023年第3期128-135,共8页
Ammonia recovery from wastewater is crucial,yet technology of low carbon emission and high ammonia perm-selectivity against complex stream compositions is urgently needed.Herein,a membrane-based hybrid process of the ... Ammonia recovery from wastewater is crucial,yet technology of low carbon emission and high ammonia perm-selectivity against complex stream compositions is urgently needed.Herein,a membrane-based hybrid process of the Donnan dialysiseelectrodialysis process(DDeED)was proposed for sustainable and efficient ammonia recovery.In principle,DD removes the majority of ammonia in wastewater by exploring the concentration gradient of NH4 t and driven cation(Nat)across the cation exchange membrane,given industrial sodium salt as a driving chemical.An additional ED stage driven by solar energy realizes a further removal of ammonia,recovery of driven cation,and replenishment of OHtoward ammonia stripping.Our results demonstrated that the hybrid DDeED process achieved ammonia removal efficiency>95%,driving cation(Nat)recovery efficiency>87.1%for synthetic streams,and reduced the OH-loss by up to 78%compared to a standalone DD case.Ammonia fluxes of 98.2 gN m^(-2)d^(-1)with the real anaerobic digestion effluent were observed using only solar energy input at 3.8 kWh kgN^(-1).With verified mass transfer modeling,reasonably controlled operation,and beneficial recovery performance,the hybrid process can be a promising candidate for future nutrient recovery from wastewater in a rural,remote area. 展开更多
关键词 Ammonia recovery Donnan Dialysis ELECTRODIALYSIS Brine utilization Anaerobic digester effluent
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Inhibition mechanisms of ammonia and sulfate in high-solids anaerobic digesters for food waste treatment: Microbial community and element distributions responses
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作者 Likui Feng Weixin Zhao +5 位作者 Yu Liu Yan Chen Shufei He Jing Ding Qingliang Zhao Liangliang Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期342-348,共7页
The horizontal flow anaerobic digester indicated that high ammonia (2923 mg/L) and SO42-(3653 mg/L)would influence the performance of methane production with food waste as substrates.Therefore,bottle anaerobic digesti... The horizontal flow anaerobic digester indicated that high ammonia (2923 mg/L) and SO42-(3653 mg/L)would influence the performance of methane production with food waste as substrates.Therefore,bottle anaerobic digestion reactors were carried out to investigate the effect of ammonia/sulfate concentrations on the methane production.Experimental results manifested that the anaerobic digesters with an ammonia concentration of 3500 mg/L or sulfate of 1600 mg/L showed the best performance of methane production,with an average methane yield of 0.32 and 0.33 L (g VS)^(-1)d^(-1),respectively.Specifically,a higher ammonia (6500 mg/L) or sulfate (1600-3500 mg/L) level hindered the bioconversion of C from liquid to gas phase (2.68%or 1.73%CH_(4)-Gas,respectively),while insignificantly for the hydrolyzation of C and N from solid to liquid phase.Similar to sulfate,high ammonia nitrogen seriously inhibited the methanation process,leading to a significant carbon accumulation in the anaerobic reactor,especially for propionic acid.The predominant archaea Methanosarcina at genus level indicated that aceticlastic methanogenesis was the major methanogenic pathway.Meanwhile,high ammonia level suppressed the activity of Methanosarcina,while modest sulfate improved H_(2)-consuming methanogens activity.A large fraction of unclassified bacteria within the Firmicutes (43.78%-63.17%) and Bacteroidetes (24.20%-33.30%) phylum played an important role in substrates hydrolysis. 展开更多
关键词 Anaerobic digestion Ammonia/sulfate inhibition Element transformation Food waste Microbial community
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens 被引量:1
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen NUTRIENTS Wall disruption Phenolic compounds In vitro digestion
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Early prediction and prevention of infected pancreatic necrosis 被引量:1
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作者 Cheng Lv Zi-Xiong Zhang Lu Ke 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1005-1010,共6页
Approximately 20%-30%of patients with acute necrotizing pancreatitis develop infected pancreatic necrosis(IPN),a highly morbid and potentially lethal complication.Early identification of patients at high risk of IPN m... Approximately 20%-30%of patients with acute necrotizing pancreatitis develop infected pancreatic necrosis(IPN),a highly morbid and potentially lethal complication.Early identification of patients at high risk of IPN may facilitate appropriate preventive measures to improve clinical outcomes.In the past two decades,several markers and predictive tools have been proposed and evaluated for this purpose.Conventional biomarkers like C-reactive protein,procalcitonin,lymphocyte count,interleukin-6,and interleukin-8,and newly developed biomarkers like angiopoietin-2 all showed significant association with IPN.On the other hand,scoring systems like the Acute Physiology and Chronic Health Evaluation II and Pancreatitis Activity Scoring System have also been tested,and the results showed that they may provide better accuracy.For early prevention of IPN,several new therapies were tested,including early enteral nutrition,anti-biotics,probiotics,immune enhancement,etc.,but the results varied.Taken together,several evidence-supported predictive markers and scoring systems are readily available for predicting IPN.However,effective treatments to reduce the incidence of IPN are still lacking apart from early enteral nutrition.In this editorial,we summarize evidence concerning early prediction and prevention of IPN,providing insights into future practice and study design.A more homo-geneous patient population with reliable risk-stratification tools may help find effective treatments to reduce the risk of IPN,thereby achieving individualized treatment. 展开更多
关键词 Acute pancreatitis Infected pancreatic necrosis BIOMARKER Scoring system Nutrition therapy Selective digestive decontamination PROBIOTICS ANTIBIOTICS Immune enhancement therapy
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Capsule endoscopy and panendoscopy:A journey to the future of gastrointestinal endoscopy 被引量:1
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作者 Bruno Rosa JoséCotter 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1270-1279,共10页
In 2000,the small bowel capsule revolutionized the management of patients with small bowel disorders.Currently,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturi... In 2000,the small bowel capsule revolutionized the management of patients with small bowel disorders.Currently,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturized devices to evaluate the small bowel and colon[pan-intestinal capsule endoscopy(PCE)],makes this non-invasive procedure a disruptive concept for the management of patients with digestive disorders.This technology is expected to identify which patients will require conventional invasive endoscopic procedures(colonoscopy or balloon-assisted enteroscopy),based on the lesions detected by the capsule,i.e.,those with an indication for biopsies or endoscopic treatment.The use of PCE in patients with inflammatory bowel diseases,namely Crohn’s disease,as well as in patients with iron deficiency anaemia and/or overt gastrointestinal(GI)bleeding,after a non-diagnostic upper endoscopy(esophagogastroduodenoscopy),enables an effective,safe and comfortable way to identify patients with relevant lesions,who should undergo subsequent invasive endoscopic procedures.The recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract,is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract,from mouth-to-anus,meeting the expectations of the early developers of capsule endoscopy. 展开更多
关键词 Non-invasive endoscopy PANENDOSCOPY Magnetically controlled capsule endoscopy Crohn’s disease Digestive bleeding
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Adsorption,in vitro digestion and human gut microbiota regulation characteristics of three Poria cocos polysaccharides 被引量:1
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作者 Fangming Zhang Hui Zheng +10 位作者 Tao Zheng Pan Xu Yao Xu Yuxin Cao Fan Jia Yiqiong Zeng Yubing Fan Kai He Xinwen Dai Fengfei Hou Yong Yang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1685-1697,共13页
Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysacch... Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine. 展开更多
关键词 Poria cocos polysaccharides Alkali-soluble poria polysaccharide Carboxymethyl poria polysaccharide Adsorption characteristics In vitro simulated digestion In vitro simulated gut microbiota fermentation
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CFD analysis for mixing performance of different types of household biodigesters 被引量:1
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作者 Sagar Shrestha Sunil Prasad Lohani 《Clean Energy》 EI 2022年第2期325-334,共10页
Household biodigesters are self-mixing anaerobic digesters used mostly in rural areas of developing countries as a reliable source of clean cooking energy.For an efficient anaerobic digestion process,the mixing of slu... Household biodigesters are self-mixing anaerobic digesters used mostly in rural areas of developing countries as a reliable source of clean cooking energy.For an efficient anaerobic digestion process,the mixing of slurry inside the digester is regarded as one of the most important parameters.In this study,the mixing of slurry in three different designs of household digesters,namely the fixed-dome digester(GGC 2047 model),plug-flow digester and prefabricated plastic digester,are investigated and compared using compu-tational fluid dynamics.A 3D transient simulation is performed using a multiphase volume of fluid(VOF)model in Ansys^(■)Fluent release 16.0.The rheological properties of the feedstock are considered identical for all three digesters.The volume of the plug-flow and prefabricated plastic digesters is designed to be 1 m^(3) while the volume of the GGC 2047 digester was 6 m^(3) as the standard size of the household digester.The regions inside the digester where the velocity of slurry is<0.02 m/s are regarded as dead zones and the obtained results were analysed and compared using velocity patterns and dead-zone formation.It is found that the prefabricated plastic digester model has a relatively higher percentage of dead volume(74.6%)and the plug-flow digester has the lowest per-centage(54%)of dead volume among digesters that were compared in this study.The study will serve as the basis for designers and researchers to improve the design of household digesters for better mixing performances. 展开更多
关键词 household biodigesters dead zone CFD anaerobic digestion MIXING BIOMASS Ansys Fluent
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Pelleting and particle size reduction of corn increase net energy and digestibility of fiber,protein,and fat in corn-soybean meal diets fed to group-housed pigs
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作者 Su A Lee Diego A.Rodriguez +1 位作者 Chad B.Paulk Hans H.Stein 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1751-1760,共10页
Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy.Pelleting may also reduce particle size of grain,but it is not known if there ... Background Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy.Pelleting may also reduce particle size of grain,but it is not known if there are interactions between particle size reduction and pelleting.The objective of this experiment was to test the hypothesis that particle size reduction and pelleting,separately or in combination,increase N balance,apparent total tract digestibility(ATTD)of fiber and fat,and net energy(NE)in corn-soybean meal diets fed to group-housed pigs.Methods Six corn-soybean meal-based diets were used in a 3×2 factorial design with 3 particle sizes of corn(i.e.,700,500,or 300μm)and 2 diet forms(i.e.,meal or pelleted).Pigs were allowed ad libitum access to feed and water.Twenty-four castrated male pigs(initial weight:29.52 kg;standard diviation:1.40)were allotted to the 6 diets using a 6×6 Latin square design with 6 calorimeter chambers(i.e.,4 pigs/chamber)and 6 periods.Oxygen consumption and CO_(2)and CH_(4)productions were measured during fed and fasting states and fecal and urine samples were collected.Results Regardless of particle size of corn,the ATTD of gross energy(GE),N,and acid-hydrolyzed ether extract(AEE),and the concentration of NE were greater(P<0.05)in pelleted diets than in meal diets.Regardless of diet form,the ATTD of GE,N,and AEE,and the concentration of NE were increased(linear;P<0.05)by reducing the particle size of corn,but the increase was greater in meal diets than in pelleted diets(interaction;P<0.05).Conclusions Both pelleting and reduction of corn particle size increased nutrient digestibility and NE,but increases were greater in meal diets than in pelleted diets. 展开更多
关键词 CORN DIGESTIBILITY Feed technology Net energy Particle size PELLETING
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Amino acid and mineral digestibility,bone ash,and plasma inositol is increased by including microbial phytase in diets for growing pigs
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作者 Liz Vanessa Lagos Mike Richard Bedford Hans Henrik Stein 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期699-712,共14页
Background The effect of microbial phytase on amino acid and energy digestibility is not consistent in pigs,which may be related to the phytase dosage or the adaptation length to the diet.Therefore,an experiment was c... Background The effect of microbial phytase on amino acid and energy digestibility is not consistent in pigs,which may be related to the phytase dosage or the adaptation length to the diet.Therefore,an experiment was conducted to test the hypotheses that increasing dietary phytase after an 18-day adaptation period:1)increases nutrient and energy digestibility;2)increases plasma P,plasma inositol,and bone ash of young pigs;and 3)demonstrates that maximum phytate degradation requires more phytase than maximum P digestibility.Results Data indicated that increasing inclusion of phytase[0,250,500,1,000,2,000,and 4,000 phytase units(FTU)/kg feed]in corn-soybean meal-based diets increased apparent ileal digestibility(AID)of Trp(quadratic;P<0.05),and of Lys and Thr(linear;P<0.05),and tended to increase AID of Met(linear;P<0.10).Increasing dietary phytase also increased AID and apparent total tract digestibility(ATTD)of Ca and P(quadratic;P<0.05)and increased ATTD of K and Na(linear;P<0.05),but phytase did not influence the ATTD of Mg or gross energy.Concentrations of plasma P and bone ash increased(quadratic;P<0.05),and plasma inositol also increased(linear;P<0.05)with increasing inclusion of phytase.Reduced concentrations of inositol phosphate(IP)6 and IP5(quadratic;P<0.05),reduced IP4 and IP3(linear;P<0.05),but increased inositol concentrations(linear;P<0.05)were observed in ileal digesta as dietary phytase increased.The ATTD of P was maximized if at least 1,200 FTU/kg were used,whereas more than 4,000 FTU/kg were needed to maximize inositol release.Conclusions Increasing dietary levels of phytase after an 18-day adaptation period increased phytate and IP ester degradation and inositol release in the small intestine.Consequently,increasing dietary phytase resulted in improved digestibility of Ca,P,K,Na,and the first 4 limiting amino acids,and in increased concentrations of bone ash and plasma P and inositol.In a corn-soybean meal diet,maximum inositol release requires approximately 3,200 FTU/kg more phytase than that required for maximum P digestibility. 展开更多
关键词 Bone ash Inositol Nutrient digestibility PHYTASE Phytate degradation PIGS
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Intricate roles of estrogen and estrogen receptors in digestive system cancers:a systematic review
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作者 Xiaoning Gan Guanqi Dai +2 位作者 Yonghao Li Lin Xu Guolong Liu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第10期898-915,共18页
Gender disparities are evident across different types of digestive system cancers,which are typically characterized by a lower incidence and mortality rate in females compared to males.This finding suggests a potentia... Gender disparities are evident across different types of digestive system cancers,which are typically characterized by a lower incidence and mortality rate in females compared to males.This finding suggests a potential protective role of female steroid hormones,particularly estrogen,in the development of these cancers.Estrogen is a well-known sex hormone that not only regulates the reproductive system but also exerts diverse effects on non-reproductive organs mediated through interactions with estrogen receptors(ERs),including the classic(ERαand ERβ)and non-traditional ERs[G protein-coupled estrogen receptor(GPER)].Recent advances have contributed to our comprehension of the mechanisms underlying ERs in digestive system cancers.In this comprehensive review we summarize the current understanding of the intricate roles played by estrogen and ERs in the major types of digestive system cancers,including hepatocellular,pancreatic,esophageal,gastric,and colorectal carcinoma.Furthermore,we discuss the potential molecular mechanisms underlying ERα,ERβ,and GPER effects,and propose perspectives on innovative therapies and preventive measures targeting the pathways regulated by estrogen and ERs.The roles of estrogen and ERs in digestive system cancers are complicated and depend on the cell type and tissue involved.Additionally,deciphering the intricate roles of estrogen,ERs,and the associated signaling pathways may guide the discovery of novel and tailored therapeutic and preventive strategies for digestive system cancers,eventually improving the care and clinical outcomes for the substantial number of individuals worldwide affected by these malignancies. 展开更多
关键词 ESTROGEN estrogen receptor CANCER digestive system cancers gender disparity
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