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1.
Sci Rep ; 14(1): 13956, 2024 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886397

RESUMEN

Co-pyrolysis of chicken manure with tree bark was investigated to mitigate salinity and potentially toxic element (PTE) concentrations of chicken manure-derived biochar. The effect of tree bark addition (0, 25, 50, 75 and 100 wt%) on the biochar composition, surface functional groups, PTEs and polycyclic aromatic hydrocarbons (PAH) concentration in the biochar was evaluated. Biochar-induced toxicity was assessed using an in-house plant growth assay with Arabidopsis thaliana. This study shows that PTE concentrations can be controlled through co-pyrolysis. More than 50 wt% of tree bark must be added to chicken manure to reduce the concentrations below the European Biochar Certificate-AGRO (EBC-AGRO) threshold. However, the amount of PAH does not show a trend with tree bark addition. Furthermore, co-pyrolysis biochar promotes plant growth at different application concentrations, whereas pure application of 100 wt% tree bark or chicken manure biochar results in decreased growth compared to the reference. In addition, increased plant stress was observed for 100 wt% chicken manure biochar. These data indicate that co-pyrolysis of chicken manure and tree bark produces EBC-AGRO-compliant biochar with the potential to stimulate plant growth. Further studies need to assess the effect of these biochars in long-term growth experiments.


Asunto(s)
Arabidopsis , Carbón Orgánico , Pollos , Estiércol , Corteza de la Planta , Pirólisis , Animales , Estiércol/análisis , Corteza de la Planta/química , Arabidopsis/efectos de los fármacos , Arabidopsis/crecimiento & desarrollo , Hidrocarburos Policíclicos Aromáticos/toxicidad
2.
Bioresour Technol ; 396: 130417, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38316229

RESUMEN

Global food waste emits substantial quantities of nitrogen to the environment (6.3 Mtons annually), chicken feather (CF) waste is a major contributor to this. Pyrolysis, in particular co-pyrolysis of nitrogen-rich and lignocellulosic waste streams is a promising strategy to improve the extent of pyrolytic nitrogen retention by incorporating nitrogen in its solid biochar structure. As such, this biochar can serve as a precursor for nitrogen-enriched activated carbons for application in supercapacitors. Therefore, this study investigates the co-pyrolysis of CF with macadamia nut shells (MNS) to create nitrogen-rich activated carbons. Co-pyrolysis increased nitrogen retention during pyrolysis from 9 % to 18 % compared to CF mono-pyrolysis, while the porosity was maintained. After removing undesirable inorganic impurities by dilute acid washing, this led to a specific capacitance of 21F/g using a scan rate of 20 mV/s. Finally, cycling stability tests demonstrated good stability with 73 % capacitance retention after 10 000 cycles.


Asunto(s)
Carbón Orgánico , Macadamia , Eliminación de Residuos , Animales , Pollos , Nitrógeno/química , Plumas , Alimentos , Pirólisis , Electrodos
3.
Sci Total Environ ; 915: 170124, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38232844

RESUMEN

Research attention is growing for biochar as amendment for anaerobic digestion (AD), as it may improve both the AD process and digestate properties. In this study, two biochars (from insect frass or the woody fraction of green waste, both pyrolyzed at 450 °C) were added (5 % w/w) during semi-continuous AD of organic kitchen waste and chicken manure. Biochar was mixed either during the AD process or to the digestate post-treatment. The impact of biochar addition on the AD process, NH3 and greenhouse gas emissions, as well as C and N mineralization following soil application, was examined. Biochar did not affect the biogas yield, but did lead to a reduction in NH3 levels in the biogas and NH4+-N sorption onto the biochars, reducing the risk of AD inhibition. N sorbed as NH4+-N onto the biochar was more available for mineralization than N sorbed as NH3. N sorption on biochar-amended digestates did not result in trade-offs when these digestates were applied to soil: the sorbed N was not released as NH3 or N2O after soil application and was not released as mineral N in either the short or medium term. The C-rich biochars increased the OC content of the digestate, which enhanced its value as soil improver. Additionally, mixing biochar with digestate decreased the soil CO2 emissions up to 33 % when it was added after AD; no priming effects were observed. These findings highlight the potential benefits of incorporating biochar into AD systems and the subsequent application of biochar-amended digestate in agricultural practices.


Asunto(s)
Biocombustibles , Carbón Orgánico , Anaerobiosis , Suelo , Fertilizantes/análisis , Óxido Nitroso/análisis
4.
Waste Manag ; 168: 376-385, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37348380

RESUMEN

Fourteen biochars from seven biomass sources were investigated on their long-term Cd2+ removal. The experiments consisted of a ten-day batch Cd2+ adsorption in a pH-buffered solution (pH = 6) to minimise pH effects. Insect frass, spent peat and chicken manure-derived biochars are promising Cd2+ adsorbents. Pyrolysis temperature was crucial for optimising Cd2+ removal by insect frass and spent peat-derived biochars. For these biochars, a pyrolysis temperature of 450 °C was optimal. In contrast, the Cd2+ removal by chicken manure biochars was independent of pyrolysis temperature. The Cd2+ removal by insect-frass and spent peat-derived biochars was associated with chemisorption on surface functionalities, while using chicken manure biochars was more associated with Cd2+ precipitation. The kinetics of Cd2+ removal over the course of ten days showed that insect frass biochar (450 °C) showed a gradual increase from 36 to 75 % Cd2+ removal, while chicken manure and spent peat-derived biochar (450 °C) already showed a higher Cd2+ removal (72 - 89 %) after day 1. This evidences that a long-term Cd2+ removal effect can be expected for some biochars. This should certainly be taken into consideration in future soil-based experiments.


Asunto(s)
Cadmio , Suelo , Animales , Estiércol , Carbón Orgánico , Adsorción , Pollos , Concentración de Iones de Hidrógeno
5.
Waste Manag ; 167: 39-45, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37244007

RESUMEN

Cattle slurry storage is a major source of gaseous N emissions. The aim of this study was to evaluate the effects of biochar, clinoptilolite and elemental sulfur (S°) on (1) NH3 and greenhouse gas emissions during storage of cattle slurry and (2) after soil application of the enriched solid fractions; and (3) on the agronomic quality of the solid and liquid fractions. In the first phase, biochar was added to the slurry (10 g L-1); subsequently in the second phase, clinoptilolite (50 g L-1), S° (1 g L-1) and 40 g L-1 extra biochar were added. Gaseous emissions were monitored by a semi-continuous multi-gas analyzer and the agronomic quality of solid and liquid fractions was assessed after separation. The enriched solid fractions were applied to soil to study the effects on gaseous emissions, N and C mineralization. Amendment of biochar reduced NH3 emissions during cattle slurry storage by 12% during the first 7 days. Extra amendment of biochar, clinoptilolite and S° in combination with biochar resulted in a decrease of NH3 emissions of approximately 20%. The N sorbed from the slurry by the biochar was not released as NH3 during soil application of the solid fractions and was not released as mineral N in the short term (within 28 days). A short-term positive priming effect of biochar on the C mineralization of manure and biochar-manure mixture applied to soil was observed. The biochar-enriched solid fractions contained more C, total and organic N and water-available P with a slow release.


Asunto(s)
Suelo , Zeolitas , Bovinos , Animales , Estiércol , Nitrógeno/análisis , Gases , Carbón Orgánico
6.
Waste Manag ; 155: 230-239, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36399850

RESUMEN

Biochar amendment during biomass processing can improve those processes and products, and reduce the emissions of greenhouse gases and NH3, resulting in ecologic and economic benefits. The potential positive effects of biochar are related to NH4+-N and NH3 sorption, which in turn are depending on different biochar characteristics. By knowing the relationship between biochar characteristics and NH4+-N and NH3 sorption, biochar production can be steered towards a higher N sorption or existing biochars can be selected for targeted applications for high N sorption. Therefore, this study aims to develop fast screening tests to estimate the potential for both NH4+-N and NH3 sorption of biochar, before application in biomass processing. Further, the effects of feedstock, pyrolysis temperature, biochar characteristics and biochar treatments on N sorption are studied. The results show that NH4+-N sorption varied between 0 and 1.54 mg NH4+-N/g fresh biochar and was highest for manure-based biochars with a high nutrient content and cation exchange capacity, produced at lower temperatures (300-450 °C). For some biochars, the feedstock itself had a higher NH4+-N sorption than the biochar. Grinding and washing increased the NH4+-N sorption. In addition, a general linear model was proposed to predict the NH4+-N sorption based on three chemical characteristics· NH3 sorption varied between 0 and 100 % of the negative control and showed a linear positive relationship with the NH4+-N sorption, moisture retention factor and cation exchange capacity. Pyrolysis temperature and feedstock type did not significantly affect NH3 sorption. NH4+-N and NH3 desorption varied amongst biochar type.


Asunto(s)
Carbón Orgánico , Biomasa , Adsorción , Carbón Orgánico/química , Cationes
7.
Cell Death Differ ; 23(8): 1283-95, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26891695

RESUMEN

A-Raf belongs to the family of oncogenic Raf kinases that are involved in mitogenic signaling by activating the MEK-ERK pathway. Low kinase activity of A-Raf toward MEK suggested that A-Raf might have alternative functions. We recently identified A-Raf as a potent inhibitor of the proapoptotic mammalian sterile 20-like kinase (MST2) tumor suppressor pathway in several cancer entities including head and neck, colon, and breast. Independent of kinase activity, A-Raf binds to MST2 thereby efficiently inhibiting apoptosis. Here, we show that the interaction of A-Raf with the MST2 pathway is regulated by subcellular compartmentalization. Although in proliferating normal cells and tumor cells A-Raf localizes to the mitochondria, differentiated non-carcinogenic cells of head and neck epithelia, which express A-Raf at the plasma membrane. The constitutive or induced re-localization of A-Raf to the plasma membrane compromises its ability to efficiently sequester and inactivate MST2, thus rendering cells susceptible to apoptosis. Physiologically, A-Raf re-localizes to the plasma membrane upon epithelial differentiation in vivo. This re-distribution is regulated by the scaffold protein kinase suppressor of Ras 2 (KSR2). Downregulation of KSR2 during mammary epithelial cell differentiation or siRNA-mediated knockdown re-localizes A-Raf to the plasma membrane causing the release of MST2. By using the MCF7 cell differentiation system, we could demonstrate that overexpression of A-Raf in MCF7 cells, which induces differentiation. Our findings offer a new paradigm to understand how differential localization of Raf complexes affects diverse signaling functions in normal cells and carcinomas.


Asunto(s)
Apoptosis , Diferenciación Celular , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas A-raf/metabolismo , Caspasa 8/metabolismo , Diferenciación Celular/efectos de los fármacos , Membrana Celular/metabolismo , Células Epiteliales/citología , Células Epiteliales/metabolismo , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Microscopía Fluorescente , Mitocondrias/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neurregulina-1/farmacología , Proteínas Proto-Oncogénicas A-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas A-raf/genética , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Serina-Treonina Quinasa 3
8.
Bioresour Technol ; 163: 228-35, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24814249

RESUMEN

The feasibility of a new concept of wastewater treatment by combining a membrane bioreactor (MBR) and a microalgae membrane photobioreactor (MPBR) is assessed in this study. In this system, the organic carbon present in wastewater is expected to be fully oxidized in the MBR, while the nutrients are removed via the subsequent MPBR treatment. The effluent of a lab-scale MBR was fed into a PBR and a MPBR which served as growing medium for Chlorella vulgaris. The MPBRs demonstrated their superiority by limiting the algae wash-out, thus increasing the allowable optimum dilution rate (Dopt). At these corresponding Dopt values, 3.5 and 2 times higher biomass concentrations and volumetric productivities respectively were achieved by the MPBR. It is also possible to run the MPBR at still higher biomass concentration, thus enabling a smaller footprint and higher nutrient removal efficiency. However, reduced nutrient removal efficiencies were found to be one possible drawback.


Asunto(s)
Chlorella vulgaris/crecimiento & desarrollo , Membranas Artificiales , Microalgas/crecimiento & desarrollo , Fotobiorreactores , Purificación del Agua/instrumentación , Biomasa , Medios de Cultivo , Aguas Residuales
9.
Bioresour Technol ; 155: 410-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24559585

RESUMEN

A new and effective concept is proposed for microalgae cultivation and pre-harvesting using a membrane photobioreactor (MPBR), in which the bioreactor is coupled to membrane filtration by cultivating Chlorella vulgaris. A basic simulation was first performed to understand the behavior of the hybrid system. The effectiveness of the MPBR for cultivation and pre-harvesting was proven. The membrane completely retained the biomass, which then was partly recycled into the bioreactor to maintain a high biomass concentration, thus enhancing flexibility and robustness of the system. The MPBR can operate at both higher dilution and higher growth rates, resulting in a 9× higher biomass productivity. In addition, pre-harvesting can be achieved by applying variable concentration factors in the filtration stage. The membrane permeate was recycled to the reactor as feed medium without affecting the algae growth, which offers a substantial reduction of 77% in the water footprint.


Asunto(s)
Reactores Biológicos/microbiología , Chlorella vulgaris/metabolismo , Membranas Artificiales , Chlorella vulgaris/crecimiento & desarrollo , Simulación por Computador , Filtración , Modelos Biológicos , Fotobiología/métodos
10.
QJM ; 106(10): 891-5, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23904523

RESUMEN

Advances in genomics and other -omic fields in the last decade have resulted in unprecedented volumes of complex data now being available. These data can enable physicians to provide their patients with care that is more personalized, predictive, preventive and participatory. The expertise required to manage and understand this data is to be found in fields outside of medical science, thus multidisciplinary collaboration coupled to a systems approach is key to unlocking its potential, with concomitant new ways of working. Systems medicine can build on the successes in the field of systems biology, recognizing the human body as the multidimensional network of networks that it is. While systems medicine can provide a conceptual and theoretical framework, its practical goal is to provide physicians the tools necessary for harnessing the rapid advances in basic biomedical science into their routine clinical arsenal.


Asunto(s)
Medicina Clínica/tendencias , Genómica/métodos , Biología de Sistemas/métodos , Manejo de la Enfermedad , Humanos , Medicina de Precisión/tendencias , Medicina Preventiva , Investigación
11.
Bioresour Technol ; 138: 329-38, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23624051

RESUMEN

This study was performed to investigate the effectiveness of submerged microfiltration to harvest both a marine diatom Phaeodactylum tricornutum and a Chlorella vulgaris in a recently developed magnetically induced membrane vibrating (MMV) system. We assess the filtration performance by conducting the improved flux step method (IFM), fed-batch concentration filtrations and membrane fouling autopsy using two lab-made membranes with different porosity. The full-scale energy consumption was also estimated. Overall results suggest that the MMV offers a good fouling control and the process was proven to be economically attractive. By combining the membrane filtration (15× concentration) with centrifugation to reach a final concentration of 25% w/v, the energy consumption to harvest P. tricornutum and C. vulgaris was, respectively, as low as 0.84 and 0.77kWh/m(3), corresponding to 1.46 and 1.39 kWh/kg of the harvested biomass.


Asunto(s)
Biomasa , Metabolismo Energético , Filtración/métodos , Magnetismo/métodos , Membranas Artificiales , Microalgas/crecimiento & desarrollo , Vibración , Técnicas de Cultivo Celular por Lotes , Chlorella/crecimiento & desarrollo , Chlorella/metabolismo , Diatomeas/crecimiento & desarrollo , Diatomeas/metabolismo , Microalgas/metabolismo , Porosidad , Propiedades de Superficie
12.
Bioresour Technol ; 129: 18-25, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23238336

RESUMEN

Recent reports show strong evidence for the involvement of transparent exopolymer particles (TEPs), mainly produced by microalgae in natural environments, in membrane fouling in a wide range of membrane filtration processes. The objective of this study is to fundamentally investigate the direct role of TEPs on membrane fouling by using different Chlorella vulgaris broth solutions and different fractions of such broth (the soluble and bound fractions, the cells separated from these fractions and the cells with their bound sugars, separated from the soluble fraction) as filtration feed. The relation between the feed properties and their filterability over three membranes was determined. Scanning electron microscopy and light microscopy showed that the foulant types differed for each broth fraction and confirmed the role of TEPs in the fouling of microfiltration membranes. In addition, this study contributes to the role of TEPs in the filtration of microalgae cultivated for commercial reasons.


Asunto(s)
Reactores Biológicos/microbiología , Chlorella vulgaris/aislamiento & purificación , Chlorella vulgaris/metabolismo , Contaminación de Equipos , Membranas Artificiales , Polisacáridos Bacterianos/aislamiento & purificación , Ultrafiltración/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Polisacáridos Bacterianos/química , Refractometría
14.
Bioresour Technol ; 111: 343-52, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22391586

RESUMEN

This study was performed to investigate the applicability of submerged microfiltration as a first step of up-concentration for harvesting both a freshwater green algae species Chlorella vulgaris and a marine diatom Phaeodactylum tricornutum using three lab-made membranes with different porosity. The filtration performance was assessed by conducting the improved flux step method (IFM) and batch up-concentration filtrations. The fouling autopsy of the membranes was performed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The cost analysis was estimated based on the data of a related full-scale submerged membrane bioreactor (MBR). Overall results suggest that submerged microfiltration for algal harvesting is economically feasible. The IFM results indicate a low degree of fouling, comparable to the one obtained for a submerged MBR. By combining the submerged microfiltration with centrifugation to reach a final concentration of 22% w/v, the energy consumption to dewater C. vulgaris and P. tricornutum is 0.84 kW h/m(3) and 0.91 kW h/m(3), respectively.


Asunto(s)
Biomasa , Filtración/instrumentación , Membranas Artificiales , Microalgas/metabolismo , Espectrometría por Rayos X
15.
Vet Clin North Am Food Anim Pract ; 5(3): 557-65, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2819545

RESUMEN

The operation of an in-house laboratory in a dairy practice is rewarding for several reasons. The quality of medicine practiced by members of the clinic improves greatly with the aid of laboratory analysis. Income is generated in proportion to the extensiveness of the laboratory workload. The veterinarian derives great satisfaction from giving high-quality medical care rather than guessing at the diagnosis. In-house laboratory testing has many advantages over mail-out sampling, from the standpoint of immediate results in emergency situations, income generation, client satisfaction, and making the practice more competitive. The whole idea of an in-house laboratory is to give the client rapid and accurate information at a reasonable cost and to provide financial remuneration to the veterinarian.


Asunto(s)
Industria Lechera , Laboratorios , Medicina Veterinaria
16.
Atherosclerosis ; 32(2): 141-53, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-222303

RESUMEN

The influence of treatment with polyunsaturated lecithin (EPL) and with saturated lecithin on the lipoprotein composition and fatty acid profile was investigated in 4 male chimpanzees. The animals were successively given 3 isocaloric diets containing the same amount of fat with a degree of saturation varying from 1 in the control diet to 0.2 in the diet enriched with polyunsaturated lecithin, to 4 in the diet enrich with saturated lecithin. The VLDL, LDL and HDL3 fractions were isolated by ultracentrifugal flotation; changes in their lipid and fatty acid composition were followed and their microviscosity was measured. The treatment with polyunsaturated lecithin increases the cholesterol esters and lysolecithin content in HDL3, presumably via activation of the enzyme LCAT. These modified HDL particles have a more fluid surface and a denser core and are susceptible to act as better cholesterol carriers. A complementary effect of this treatment is a decrease of the plasma triglycerides and VLDL concentration, an increase in the unsaturation ratio of the triglycerides which might take place via activation of triglyceride lipase. The saturated lecithin treatment increases the plasma VLDL and LDL concentrations and the triglyceride levels and increases mostly the saturation ratio of the cholesterol esters. These effects are likely to enhance the progression of atherosclerosis.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Ácidos Grasos/sangre , Lipoproteínas/sangre , Fosfatidilcolinas/administración & dosificación , Triglicéridos/sangre , Administración Oral , Animales , Ésteres del Colesterol/sangre , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lipoproteínas VLDL/sangre , Masculino , Pan troglodytes , Viscosidad
17.
Clin Chim Acta ; 89(2): 231-8, 1978 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-709873

RESUMEN

Thin-layer chromatography was carried out on glass rods coated with Silica gel (chromarod) and the fractions were detected with a flame ionization detector (FID). This system was applied to the fractionation and screening of plasma lipids. As the relative response of the flame ionization detector depends on the nature of the lipids, correction factors had to be introduced. These correction factors were derived from comparison of the results of the thin-layer chromatography with flame ionization detection with those obtained by conventional chemical analysis of the same sample. The coefficients of variation of the lipid profiles were comparable for both techniques. The absolute lipid concentration for the various fractions obtained by combination of the concentration of the total lipids with the relative lipid profile, correlate very well with the values obtained by conventional chemical analysis of the various lipids.


Asunto(s)
Lípidos/sangre , Colesterol/sangre , Ésteres del Colesterol/sangre , Cromatografía en Capa Delgada/métodos , Computadores , Humanos , Fosfolípidos/sangre , Triglicéridos/sangre
19.
Arzneimittelforschung ; 27(10): 1964-7, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-411499

RESUMEN

A novel potent vasoactive agent, 1-(4-isopropyl-thiophenyl)-2-n-octylaminopropanol (suloctidil, Sulocton), lowers excess of plasma cholesterol and tends to normalize the plasma hyperbetalipoproteinemia of Rhesus monkeys fed a high-cholesterol, high-fat diet. The drug shows an inhibitory effect on the cholesterol biosynthesis in rat liver homogenates.


Asunto(s)
Metabolismo de los Lípidos , Propanolaminas/farmacología , Animales , Colesterol/biosíntesis , Colesterol/sangre , Ácidos Grasos/sangre , Haplorrinos , Técnicas In Vitro , Lipoproteínas/sangre , Hígado/metabolismo , Macaca mulatta , Masculino , Fosfolípidos/sangre , Ratas
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