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1.
BMC Palliat Care ; 23(1): 109, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671419

RESUMO

OBJECTIVES: Many associations have recently recommended early integration of oncology and palliative care for more standard cancer care and better quality of life. We aimed to create a questionnaire to assess the opinion of medical oncologists and nurses about the clinical impact of the integrated palliative care and oncology (PCO) program. METHODS: A novel semi-structured questionnaire called Impact of Early Integration of Palliative Care Oncology (IEI PCO) questionnaire was developed and tested for validity and reliability then distributed to the oncologists and nurses working in Kuwait Cancer Control Center. RESULTS: After the pilot stage, testing the final questionnaire for validity and reliability was done with satisfactory results. Finally, the complete questionnaires were 170 out of 256 (response rate 66.41%). More awareness about the available palliative care services and the new available PCO services (p-value < 0.001 for all). Most of the oncologists and nurses agreed with the currently available structure of PCO, appreciated the patients' discharge plan and continuity of care of palliative medicine, admitted less work burden, a better attitude, and higher satisfaction (p-value for all < 0.001) toward palliative care. Significant improvements in symptoms were appreciated by oncologists and nurses after the integration of palliative care (p-value for all < 0.001. Oncologists and nurses valued repeated honest communication, discussion of the goals of care, dealing more effectively with ending active treatment, and higher acceptance of patients and families of PC policy of transfer, and significant progress in the care of end-of-life symptoms (p-value for all < 0.001). CONCLUSIONS: The IEI PCO questionnaire demonstrated the psychometric criteria for content, face, and construct validity and reliability. It provides a valuable tool to assess the impact of PCO integration. The opinion of medical oncologists and nurses was significantly positive toward the early integration of PCO in Kuwait in most aspects of care. This integration led to improved symptom control, end-of-life care, communication, and planned discharge and follow-up plans. Moreover, decreases the work burden, improves attitude, higher satisfaction of the oncology staff, and continuity of care.


Assuntos
Oncologistas , Cuidados Paliativos , Humanos , Inquéritos e Questionários , Cuidados Paliativos/métodos , Cuidados Paliativos/normas , Feminino , Masculino , Kuweit , Reprodutibilidade dos Testes , Adulto , Pessoa de Meia-Idade , Oncologistas/psicologia , Oncologistas/normas , Enfermeiras e Enfermeiros/psicologia , Enfermeiras e Enfermeiros/estatística & dados numéricos , Psicometria/instrumentação , Psicometria/métodos , Oncologia/métodos , Oncologia/normas , Atitude do Pessoal de Saúde , Prestação Integrada de Cuidados de Saúde/métodos , Prestação Integrada de Cuidados de Saúde/normas
2.
Bioresour Technol ; 394: 130282, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38163488

RESUMO

The design of novel electrode deflector structures (EDSs) introduced a promising strategy for enhancing raceway ponds performance, increasing carbon fixation, and improving microalgal biomass accumulation. The computational fluid dynamics, based flow field principles, proved that the potency of arc-shaped electrode deflector structures (A-EDS) and spiral electrode deflector structures (S-EDS) were optimal. These configurations yielded superior culture effects, notably reducing dead zones by 9.1% and 11.7%, while elevating biomass increments of 14.7% and 11.5% compared to the control, respectively. In comparison to scenarios without electrostatic field application, the A-EDS group demonstrated pronounced post-stimulation growth, exhibiting an additional biomass increase of 11.2%, coupled with a remarkable 23.6% surge in CO2 fixation rate and mixing time reduction by 14.7%. A-EDS and S-EDS, combined with strategic electric field integration, provided a theoretical basis for promoting microalgal biomass production and enhancing carbon fixation in a raceway pond environment to similar production practices.


Assuntos
Microalgas , Lagoas , Biomassa , Hidrodinâmica
3.
Bioresour Technol ; 394: 130209, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38135224

RESUMO

Urban areas remarkably affect global public health due to their emissions of greenhouse gases and poor air quality. Although urban areas only cover 2% of the Earth's surface, they are responsible for 80% of greenhouse gas emissions. Dense buildings limit vegetation, leading to increased air pollution and disruption of the local and regional carbon cycle. The substitution of urban gray roofs with microalgal green roofs has the potential to improve the carbon cycle by sequestering CO2 from the atmosphere. Microalgae can fix 15-50 times more CO2 than other types of vegetation. Advanced microalgal-based green roof technology may significantly accelerate the reduction of atmospheric CO2 in a more effective way. Microalgal green roofs also enhance air quality, oxygen production, acoustic isolation, sunlight absorption, and biomass production. This endeavor yields the advantage of simultaneously generating protein, lipids, vitamins, and a spectrum of valuable bioactive compounds, including astaxanthin, carotenoids, polysaccharides, and phycocyanin, thus contributing to a green economy. The primary focus of the current work is on analyzing the ecological advantages and CO2 bio-fixation efficiency attained through microalgal cultivation on urban rooftops. This study also briefly examines the idea of green roofs, clarifies the ecological benefits associated with them, discusses the practice of growing microalgae on rooftops, identifies the difficulties involved, and the positive aspects of this novel strategy.


Assuntos
Gases de Efeito Estufa , Microalgas , Fotobiorreatores , Dióxido de Carbono/metabolismo , Microalgas/metabolismo , Microclima , Biomassa
4.
Bioresour Technol ; 394: 130241, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142911

RESUMO

Rotifer reproduction control in open microalgae cultivation systems poses a significant challenge for large-scale industries. Conventional methods, such as electric, meshing, and chemical techniques, are often expensive, ineffective, and may have adverse environmental-health impacts. This study investigated a promising control technique through light-induced phototaxis to concentrate rotifers in a specific spot, where they were electroshocked by local-limited exposure dose. The results showed that the rotifers had the most pronounced positive and negative phototropism with phototaxis rates of 66.7 % and -78.8 %, respectively, at blue-light irradiation of 30 µmol∙m-2∙s-1 and red-light irradiation of 22.5 µmol∙m-2∙s-1 for 20 min. The most effective electroshock configuration employed 1200 V/cm for 15 min with a 1-second cycle time and a 10 % duty cycle, resulting in a 75.0 % rotifer removal rate without impacting microalgae growth. The combination of the two light beams could effectively lead rotifers to designated areas where they were electrocuted successfully.


Assuntos
Microalgas , Lagoas , Fototaxia , Eletrochoque , Luz Azul , Biomassa
5.
Sci Total Environ ; 894: 165044, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37355125

RESUMO

This study focuses on microbial protein (MP) as a promising food-feed alternative source that may contribute to overcoming the increased food challenge. It analyzes the traditional and advanced MP technologies, their progress, sustainability, and environmental limitations. Traditional MP technologies are reliable for global food-feed supply chains but face higher production costs and negative environmental impacts. Advanced MP systems utilize sustainable sources like food waste, but limited availability and characteristics necessitate pretreatments. Power-to-protein technology looks promising due to its ability to capture CO2 and avoiding external organic carbon addition, although more research is still needed. Cultivating indigenous microorganisms in agricultural wastewater, such as biofloc technology, offer potential for nutrient recovery and reduced environmental impacts. Microalgal biomass is sustainable but faces challenges of low palatability, productivity, and high costs, while ongoing studies try to solve these challenges. This review concludes that the advanced MP technologies are environmentally friendly and promising, while further studies are necessary to enhance performance and commercial implementation.


Assuntos
Microalgas , Eliminação de Resíduos , Alimentos , Águas Residuárias , Meio Ambiente , Biomassa , Tecnologia , Microalgas/metabolismo
6.
J Environ Manage ; 328: 116975, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36527801

RESUMO

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.


Assuntos
Pegada de Carbono , Esterco , Dióxido de Carbono/análise , Análise da Demanda Biológica de Oxigênio , Nitrogênio , Fósforo
7.
Sci Total Environ ; 857(Pt 3): 159536, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36280067

RESUMO

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.


Assuntos
Compostos Heterocíclicos , Oxitetraciclina , Suínos , Animais , Oxitetraciclina/metabolismo , Esterco/microbiologia , Tetraciclina , Sulfadiazina , Norfloxacino , Anaerobiose , Antibacterianos/metabolismo , Tetraciclinas
8.
Eur J Haematol ; 109(5): 494-503, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35871389

RESUMO

OBJECTIVES: The benefits and risks of thromboprophylaxis usage in patients with advanced cancer at the end of their lives remain unknown, especially with the lack of randomized studies. This study aimed to describe the clinical use of thromboprophylaxis in those patients under palliative care. METHODS: A retrospective cohort study. It was performed on patients admitted to the Palliative Care Center. RESULTS: A total of 719 patients were enrolled in the study. The mean age was 62.97 (13.65) years. Venous thromboembolism (VTE) incidence was 5.4% (n = 39). At the time of admission, 31.29% (n = 225) of patients were on thromboprophylaxis. At death time, 17.5% (n = 126) of patients were on thromboprophylaxis (41.3% on primary and 58.7% on secondary thromboprophylaxis). The incidence of clinically suspected fatal VTE was 6.5% (n = 47). Surprisingly, clinically suspected VTE was higher statistically in patients with thromboprophylaxis rather than in non-thromboprophylaxis (p < .001). By using linear regression, only higher PPI scores on admission were independent negative predictors of length of stay (OR:4.429, 95% CI: 5.460-3.398, p < .001). The development of clinically suspected fatal VTE, whatever the status of thromboprophylaxis, did not affect the length of stay. CONCLUSIONS: Thromboprophylaxis does not decrease the risk of clinically suspected fatal VTE in patients with advanced disease in their terminal phase. Patients with poor performance status and a short prognosis are unlikely to benefit from thromboprophylaxis.


Assuntos
Neoplasias , Tromboembolia Venosa , Anticoagulantes/uso terapêutico , Humanos , Pacientes Internados , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Cuidados Paliativos , Estudos Retrospectivos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
9.
Sci Total Environ ; 838(Pt 1): 155921, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35577093

RESUMO

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.


Assuntos
Esterco , Fósforo , Anaerobiose , Animais , Digestão , Temperatura , Triticum
10.
Sci Total Environ ; 814: 152700, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34973327

RESUMO

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.


Assuntos
Biocombustíveis , Fertilizantes , Anaerobiose , Nutrientes
11.
Antibiotics (Basel) ; 10(11)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34827335

RESUMO

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.

13.
J Environ Manage ; 294: 112956, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34126527

RESUMO

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.


Assuntos
Gases de Efeito Estufa , Anaerobiose , Efeito Estufa , Esterco/análise , Metano , Nutrientes
14.
Bioresour Technol ; 333: 125069, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33894445

RESUMO

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.


Assuntos
Compostagem , Esterco , Animais , Antibacterianos , Gado , Tetraciclinas
16.
BMC Palliat Care ; 20(1): 25, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536013

RESUMO

BACKGROUND: Cancer-related pain is a complicated symptom that often coincides with fatigue, depression, and anxiety. Although many safe treatments are available, inadequate control of Cancer-related pain continues to lead to suffering in cancer patients. This study's aim is to describe pain control, and the pattern of change in opioid and adjuvant medication prescriptions, before and after referral to the Palliative Care Center. METHODS: We conducted a prospective cohort study in adult cancer patients the Palliative Care Center between January 1, 2016 and December 30, 2017. We measured pain intensity and other associated symptoms via the Revised Edmonton Symptom Assessment System (ESAS-r) and documented detailed analgesics and adjuvant medication history before starting any palliative care and on days 0, 3, 6, and 14. RESULTS: The analysis included 240 patients whose cancer-related pain, anxiety, and depression scores meaningfully improved by day 6. The changes in the median (interquartile ranges) of Cancer-related pain, anxiety, and depression scores from day 0 to day 6 were: 6 (4-8) to 3 (1-4); 6 (4-9) to 2 (1-4); and 3 (2-6) to 2 (1-4), respectively, with p < 0.001 for all. Morphine was the most common opioid administered; the percentage using it increased from 20.4% (n = 49) before referral to 49.6% (n = 119) on day 6 (p < 0.001). The median morphine equivalent daily dose decreased from a median (interquartile ranges) of 60(31-93) mg/day before referral to 34(22-66) mg/day on day 6 (p < 0.001). There was also a statistically significant increase in the percentage of patients taking adjuvant medications, from 38.8% before referral to 84.2% on day 6 (p < 0.001). Comparing D0 to D6, the number of patients using Gabapentinoids significantly increased from 57(23.75%) to 79(32.9%) (p < 0.001), amitriptyline dramatically increased from 14 (5.8%) to 44 (18.3%) (p < 0.001), and other antidepressant drugs increased from 15 (6.2%) to 34 (14.1%) (p < 0.001). CONCLUSION: After referral to the Palliative Care Center, patients' pain and other symptoms scores decreased significantly, even with lower median morphine equivalent daily doses, arguably through more appropriately directed opioid use. This is evidence for the effectiveness of the comprehensive program at the Palliative Care Center in Kuwait.


Assuntos
Dor do Câncer , Neoplasias , Adulto , Analgésicos Opioides/uso terapêutico , Dor do Câncer/tratamento farmacológico , Humanos , Kuweit , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Cuidados Paliativos , Prescrições , Estudos Prospectivos , Encaminhamento e Consulta
17.
Environ Sci Pollut Res Int ; 28(20): 25664-25678, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33464529

RESUMO

Though having an economic and ecological impact on Marriott Lake management in Egypt, water hyacinth (Eichhornia crassipes) is an aquatic floating macrophyte with a known phytoremediation potential. In order to assess its remediation potential, pilot floating treatment wetlands (FTWs) with E. crassipes were built in duplicates to evaluate the removal of nutrients and heavy metals from the polluted lake water. The experimental design included units with different water depths (15, 25, and 35 cm; D15, D25, and D35, respectively) and plant coverage (90, 70, 50, and 0%; P90, P70, P50, and P0, respectively). The pilot FTWs were monitored over a 7-day operation cycle to identify the optimum combination of design (plant coverage, water depth) and operation (hydraulic retention time; HRT) parameters needed for maximum BOD5, TN, NH4-N, and TP removal. NH4-N removal reached 97.4% in the D25P50 unit after 3 days, BOD5 75% in the D15P90 after 3 days, TN 82% in the D25P70 after 4 days, and TP 84.2% in the D35P70 after 4 days. The open-water evaporation rate was higher than the evapotranspiration rate in the planted units, probably due to the warm climate of the study area. Metals were also sufficiently removed through bioaccumulation in plant tissues in the order of Fe > Pb > Cu > Ni (62.5%, 88.9%, 81.7%, and 80.4% for D25P50, D25P70, D25P50, and D25P90, respectively), while most of the assimilated metal mass was translocated to the plant roots. The biochemical composition of the plant tissue was significantly different between the shoot and root parts. Overall, the FTW with 70% E. crassipes coverage, 25-cm water depth, and an HRT of 3-5 days was identified as the optimum design for effective remediation of the polluted Marriott Lake in Egypt.


Assuntos
Eichhornia , Metais Pesados , Poluentes Químicos da Água , Biodegradação Ambiental , Egito , Lagos , Metais Pesados/análise , Nutrientes , Eliminação de Resíduos Líquidos , Água , Poluentes Químicos da Água/análise , Áreas Alagadas
18.
Sci Total Environ ; 757: 143751, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33250259

RESUMO

Low contents of water-soluble carbohydrates and/or low indigenous microbial activity in wilted maize stover (WMS) usually hinder the establishment of the ensiling process, thereby resulting in a low biogas production because of high loss of dry matter (DM). To enhance the biological activity and substrate biodegradability, this study applied the synergistic regulation of sucrose (carbon source) and increasing levels of urea (nitrogen source) during the ensiling process of WMS. Compared with the application of only sucrose, a higher organic acid content (lactic acid (85 g/kg-DM) and acetic acid (14 g/kg-DM)) and higher degradation ratios for lignocellulose (hemicellulose (28%), cellulose (22%), and lignin (17%)) were observed with urea applications of 1.7% (DM) and 3.9% (DM), respectively. This was caused by the enhanced activities of the hetero-fermenter (Weissella) and cellulolytic bacteria (Cellulosimicrobium). A simultaneous addition of urea and sucrose during the ensiling of WMS increased the specific methane yield by 11.2%-21.1% in comparison to raw WMS. Moreover, an economic cost estimation revealed that this approach could be an effective storage strategy for the efficient production of methane when employing a 1.7% (DM) urea application.


Assuntos
Ureia , Zea mays , Biocombustíveis , Fermentação , Metano , Silagem/análise
19.
Sci Total Environ ; 737: 140234, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783845

RESUMO

Phosphorus (P) loss from livestock and poultry industry causes serious threat to agro-ecological environments. Anaerobic digestion (AD), through recycling of P-containing resources and biogas production, prevails as a promising solution to the resource, energy, and environment trilemma. In this study, the dynamic transformation of P in batch AD processes fed with chicken, pig and dairy manures was investigated. Results showed that the Labile-P of total phosphorus (TP) in pig, chicken and dairy manure digestates decreased from 37.35% to 23.79%, 36.79% to 17.29%, and 60.47% to 20.39%, respectively, and was associated with an increase of NaOH-P during the AD process. However, the Labile-P in raw manures ranging from 64.67% to 81.10%, indicated that AD could reduce the pollution risk caused by the overuse of high Labile-P animal manure as fertilizer. Metal ions had a significant influence on P transformation because of their ability to combine with PO43-/HPO42-. During AD, the species of phosphates increased: AlPO4, FePO4, Mg3(PO4)2, CaHPO4, Mg(NH4)PO4·6H2O and Ca10(PO4)6(OH)2 were the main phosphates qualified by X-ray diffraction (XRD). AD produced a satisfactory fertilizer for plants that were able to activate the precipitated P, which could provide readily available N and slow-release P. This study provides a meaningful theoretical guide for recycling P from animal manure resources.


Assuntos
Esterco , Fósforo , Anaerobiose , Animais , Biocombustíveis , Galinhas , Suínos
20.
Sci Total Environ ; 690: 492-501, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31301490

RESUMO

Nutrient overloading resulting from digestate (effluent of anaerobic digestion process) application has become a major bottleneck for the development of the biogas industry and raised environmental concerns in regions with intensive animal husbandry. Due to this, it is imperative to find low cost and effective alternative to export nutrient from digestate. Among the numerous applications, indigenous microflora has recently been utilized successfully as a biofloc technology in aquatic systems for controlling ammonia and subsequent reduction of feeding cost. Accordingly, performance of the indigenous microflora in undiluted liquid digestate of chicken manure was evaluated in this study to recover nutrients and produce high-value biomass under aerobic heterotrophic mode in batch shaking experiments. The results showed that 68% of phosphate was recovered and 97% of total nitrogen was removed from the liquid digestate. Additionally, >6 g L-1 of dry biomass was simultaneously produced and featured with up to 65% crude protein without pathogens, 10.9% lipids, 10.7% ash and 19.6 MJ kg-1 gross energy. Therefore, the produced biomass could be used either as an alternative sustainable source for animal or fish feeding or as a substrate for energy applications.

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