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During the establishment of neuronal circuits, axons and dendrites grow and branch to establish specific synaptic connections. This complex process is highly regulated by positive and negative extracellular cues guiding the axons and dendrites. Our group was pioneer in describing that one of these signals are the extracellular purines. We found that extracellular ATP, through its selective ionotropic P2X7 receptor (P2X7R), negatively regulates axonal growth and branching. Here, we evaluate if other purinergic compounds, such as the diadenosine pentaphosphate (Ap5A), may module the dynamics of dendritic or axonal growth and branching in cultured hippocampal neurons. Our results show that Ap5A negatively modulates the dendrite's growth and number by inducing transient intracellular calcium increases in the dendrites' growth cone. Interestingly, phenol red, commonly used as a pH indicator in culture media, also blocks the P2X1 receptors, avoided the negative modulation of Ap5A on dendrites. Subsequent pharmacological studies using a battery of selective P2X1R antagonists confirmed the involvement of this subunit. In agreement with pharmacological studies, P2X1R overexpression caused a similar reduction in dendritic length and number as that induced by Ap5A. This effect was reverted when neurons were co-transfected with the vector expressing the interference RNA for P2X1R. Despite small hairpin RNAs reverting the reduction in the number of dendrites caused by Ap5A, it did not avoid the dendritic length decrease induced by the polyphosphate, suggesting, therefore, the involvement of a heteromeric P2X receptor. Our results are indicating that Ap5A exerts a negative influence on dendritic growth.
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Adenosina Trifosfato , Fosfatos de Dinucleósidos , Receptores Purinérgicos P2 , Adenosina Trifosfato/farmacología , Receptores Purinérgicos P2/metabolismo , Neuronas/metabolismo , Dendritas/metabolismo , Hipocampo/metabolismoRESUMEN
Elephant grass [Pennisetum purpureum Schumach. syn. Cenchrus purpureus (Schumach.) Morrone], also known as Napier grass and King grass, includes varieties Taiwán, Gigante, Merkerón, Maralfalfa, and others. The grass achieves high biomass production in tropical-subtropical, temperate, and arid areas. The high-water concentration of elephant grass suggests that ensiling could offer an alternative way to preserve the nutritional quality of the grass during storage, however, some considerations should be addressed because of the particularities of the grass. Ensiling elephant grass may produce adequate fermentation but could suffer effluent losses and subsequent losses of nutrients due to leaching. To improve fermentation and nutrient characteristics of elephant grass silages, several studies were conducted with the inclusion of additives. Lactic acid bacteria inocula have reduced pH and increased crude protein content of elephant grass silage, but aerobic stability of silages could be affected by the bacterial inoculation. There is limited information, however, on the potential of different silage inoculants to reduce growth of spoilage microorganisms during the aerobic phase of silage prepared with elephant grass. Exogenous fibrolytic enzymes also may improve elephant grass silage quality by enhancing microbial fiber-degradation with subsequent increase in lactic acid and its associated pH reduction. Another study approach to improve fermentation and nutritional quality of elephant grass silages involved the addition of different feeds at ensiling, including conventional feeds such corn, wheat, rice bran, and molasses or alternative feeds such as different dehydrated by-products obtained from the food industries of juice and jelly. In the manuscript, the presented scientific information shows the great potential of the different manipulations to improve the quality of elephant grass silages and with possible enhance of the economic profit and sustainability of livestock farming in the tropical areas.
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Fermentación , Valor Nutritivo , Ensilaje , Ensilaje/análisis , Animales , Cenchrus , PennisetumRESUMEN
PURPOSE OF REVIEW: Pathologies of the prostate in men are one of the most prevalent clinical conditions today [1]. Specifically, pelvic inflammatory disease such as prostatitis can cause symptoms and syndromes different from urological ones, such as bowel or nervous system manifestations. This has a largely negative impact on the quality of life of patients. Therefore, it is convenient to know and update the information about the therapeutic approach to prostatitis, which is a challenge that involves different medical specialties. The aim of this article is to provide summarized and focused evidence to help in the therapeutic approach of patients with prostatitis. A computer-based search of the PubMed and Cochrane Library databases was used to perform a comprehensive literature review on prostatitis, with special interest in recent findings and latest therapeutic guideline recommendations. RECENT FINDINGS: Recent discoveries about the epidemiology and clinical classifications of prostatitis seem to incur in an increasingly individualized and directed management, with the aim of covering all the confluent factors in prostatic inflammatory pathology. In addition, the role of new drugs and combination with phytotherapy open up a range of new treatment possibilities, although future randomized studies will be necessary to better understand how to use all treatment modalities. Despite all the knowledge acquired about the pathophysiology of prostate diseases, and due to their interrelation with other pelvic systems and organs, there are still gaps that make it difficult for us to provide an optimal and standardized treatment in many of our patients. Being aware of the influence of all the factors potentially involved in prostate symptoms is crucial for a correct diagnosis and establishing an effective treatment plan.
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Prostatitis , Masculino , Humanos , Enfermedad Crónica , Prostatitis/diagnóstico , Calidad de Vida , Dolor Pélvico/terapia , Fitoterapia/efectos adversosRESUMEN
BACKGROUND: Although partial onychectomy with chemical matricectomy has been described asthe treatment of choice, there is sparse evidence in the literature regarding the use of silvernitrate for matricectomy. Our aim is to describe the effectiveness of silver nitrate for matrixcauterization after partial onychectomy. METHODS: A prospective observational study was performed on patients with ingrown toenailsstage 2-3 who underwent partial onychectomy with silver nitrate chemical matricectomy during 2018-2019 in our institution. All patients were evaluated in the outpatient clinic on the 7th and 30th post-operative day and a telephone evaluation was performed every 6 months afterthe surgical procedure to date. RESULTS: One hundred and twenty-three patients, who underwent 231 partial onychectomies with silver nitrate chemical matricectomy were included, with a median follow-up of 21 months (interquartile range, 12-29). The procedure had an effectiveness of 95.3%, with only 11 recur-rences (4.7%) reported so far on follow-up. Postoperative infections were observed in 4 patients (1.7%). Adverse effects, such as pain and postoperative drainage, were irrelevant in mostpatients. CONCLUSIONS: Silver nitrate matricectomy after partial onychectomy is an effective and safealternative for the treatment of ingrown toenail in children, with scarce postoperative morbidityand low recurrence rate.
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Uñas Encarnadas , Uñas , Humanos , Niño , Uñas/cirugía , Proyectos Piloto , Nitrato de Plata/uso terapéutico , Uñas Encarnadas/cirugía , Cauterización/métodos , Colorantes , RecurrenciaRESUMEN
BACKGROUND: Although partial onychectomy with chemical matricectomy has been described as the treatment of choice, there is sparse evidence in the literature regarding the use of silver nitrate for matricectomy. Our aim is to describe the effectiveness of silver nitrate for matrix cauterization after partial onychectomy. METHODS: A prospective observational study was performed on patients with ingrown toenails stage 2-3 who underwent partial onychectomy with silver nitrate chemical matricectomy during 2018-2019 in our institution. All patients were evaluated in the outpatient clinic on the 7th and 30th post-operative day and a telephone evaluation was performed every 6 months after the surgical procedure to date. RESULTS: One hundred and twenty-three patients, who underwent 231 partial onychectomies with silver nitrate chemical matricectomy were included, with a median follow-up of 21 months (interquartile range, 12-29). The procedure had an effectiveness of 95.3%, with only 11 recurrences (4.7%) reported so far on follow-up. Postoperative infections were observed in 4 patients (1.7%). Adverse effects, such as pain and postoperative drainage, were irrelevant in most patients. CONCLUSIONS: Silver nitrate matricectomy after partial onychectomy is an effective and safe alternative for the treatment of ingrown toenail in children, with scarce postoperative morbidity and low recurrence rate.
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Uñas Encarnadas , Uñas , Humanos , Niño , Uñas/cirugía , Proyectos Piloto , Nitrato de Plata/uso terapéutico , Uñas Encarnadas/cirugía , Cauterización/métodos , RecurrenciaRESUMEN
BACKGROUND: The risk of developing Alzheimer's disease (AD) is modulated by genetic and environmental factors. Early-life stress (ELS) exposure during critical periods of brain development can impact later brain function and health, including increasing the risk of developing AD. Microglial dysfunction and neuroinflammation have been implicated as playing a role in AD pathology and may be modulated by ELS. To complicate matters further, sex-specific effects have been noted in response to ELS and in the incidence and progression of AD. METHODS: Here, we subjected male and female mice with either a wild type or 5xFAD familial AD-model background to maternal separation (MS) from postnatal day 2 to 14 to induce ELS. RESULTS: We detected hippocampal neuroinflammatory alterations already at postnatal day 15. By 4 months of age, MS mice presented increased immobility time in the forced swim test and a lower discrimination index in the novel object recognition memory test compared to controls. We found altered Bdnf and Arc expression in the hippocampus and increased microglial activation in the prefrontal cortex due to MS in a sex-dependent manner. In 5xFAD mice specifically, MS exacerbated amyloid-beta deposition, particularly in females. In the periphery, the immune cell population was altered by MS exposure. CONCLUSION: Overall, our results demonstrate that MS has both short- and long-term effects on brain regions related to memory and on the inflammatory system, both in the brain and periphery. These ELS-related effects that are detectable even in adulthood may exacerbate pathology and increase the risk of developing AD via sex-specific mechanisms.
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Enfermedad de Alzheimer , Encéfalo , Factores Sexuales , Estrés Psicológico , Animales , Femenino , Masculino , Ratones , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Encéfalo/inmunología , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Privación Materna , Ratones TransgénicosRESUMEN
Terahertz time-domain spectroscopy (THz-TDS) has shown promise in biomedical sample characterization and high characterization sensitivity is in demand due to the thin-film (TF) feature of the sample. This paper proposes an optimized multilayer structure for sensitive characterization of TF aqueous solutions in reflection THz-TDS. Theoretical simulations are conducted for structural optimization and the 75 µm window-sample-mirror structure displays the best sensitivity compared to other sandwich structures and traditional THz measurement geometries. 0-20% TF glucose solutions are then measured; and a spectral peak introduced by the proposed structure is observed to result in the high sensitivity. Our work provides a new way of customizing multilayer structure for THz thin-film characterization.
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Espectroscopía de Terahertz , Glucosa , Espectroscopía de Terahertz/métodos , AguaRESUMEN
BACKGROUND: An analysis was made of the correlation between root width, the thickness of the remaining dentinal wall as determined by endoscopy, and the outcome of periapical surgery. MATERIAL AND METHODS: A retrospective cohort study was carried out involving patients subjected to periapical surgery between 2017 and 2019 at the University of Valencia (Valencia, Spain). One year after surgery, cone-beam computed tomography (CBCT) was used to evaluate healing against the preoperative volumes. The maximum root width was measured on the postoperative CBCT scan at the apical section of the treated root. This measurement was transferred to the intraoperative endoscopic image, where the minimum root width, peripheral dentin thickness, and minimum dentin thickness were recorded. Root measurements, and the position (maxillary or mandibular) and type of tooth (roots of incisors, canines, premolars or molars) were further correlated to periapical surgery outcome. RESULTS: A total of 51 patients, comprising 52 teeth and 62 roots, were included in the study. The mean measurements were: maximum root width (4.13±0.84 mm), minimum root width (2.46±0.72 mm), peripheral dentin thickness (0.77±0.2 mm) and minimum dentin thickness (0.4±0.2 mm). The success rate was 82.2%. Premolar roots showed a greater minimum dentin thickness (0.58±0.25 mm) (p<0.003) than incisor roots. No significant association was found between the different measurements and the healing rate at one year, though the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly. The position and type of tooth did not influence healing outcome. CONCLUSIONS: The root width and thickness of the remaining dentin wall did not significantly influence healing. However, the roots that failed to heal showed smaller minimum dentin thickness values than the roots that healed correctly.
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Tomografía Computarizada de Haz Cónico , Raíz del Diente , Estudios de Cohortes , Tomografía Computarizada de Haz Cónico/métodos , Dentina , Endoscopía , Humanos , Estudios Retrospectivos , Raíz del Diente/diagnóstico por imagen , Raíz del Diente/cirugíaRESUMEN
BACKGROUND: A study is made of the findings of high-magnification rigid endoscopy at the root end surface following apicoectomy of teeth subjected to periapical surgery. MATERIAL AND METHODS: A cross-sectional study was made of patients subjected to periapical surgery at the Unit of Oral Surgery and Implantology (University of Valencia, Valencia, Spain) between 2011 and 2019. Following apicoectomy, the root end surfaces were inspected, with the evaluation of untreated canals, isthmuses, craze lines, crack lines, opaque dentin and gaps. Likewise, an analysis was made of the association between patient age and the tooth type and restoration and the presence of craze lines, cracks, opaque dentin and gaps. RESULTS: The final sample consisted of 168 patients subjected to periapical surgery, with 177 operated teeth and 206 roots. Untreated canals were observed in 14 roots (6.8%). Isthmuses were identified in 74 roots (35.9%), particularly in the mesial root of the lower first molar (94.1%). In turn, craze lines were identified in 8.3% of the roots, cracks in 3.9%, and gaps in 53.4%. The prevalence of opaque dentin was 78.3%, with a greater presence in posterior teeth (90.3% in premolars and 86.2% in molars) than in anterior teeth (50.6%) (p<0.001). Patient age and tooth restoration showed no correlation to the studied parameters. CONCLUSIONS: Craze lines and crack lines were observed in less than 10% of the roots, though opaque dentin was identified in 73% of the roots, particularly in posterior teeth, and gaps were found in over half of the canals.
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Apicectomía , Cavidad Pulpar , Estudios Transversales , Humanos , Diente Molar , Raíz del Diente/cirugíaRESUMEN
Genetic resistance is the most recommended measure to control verticillium wilt in olive (VWO), a vascular disease caused by the soil-borne fungus Verticillium dahliae, which has promoted the development of olive breeding programs aimed at obtaining new resistant and highly yielding cultivars in recent years. Screening has been commonly performed under controlled conditions in grow chamber after artificial inoculation during the early stage of breeding programs, but additional evaluation is necessary to confirm previous results as well as to test for additional agronomic traits. During this study, 20 breeding selections initially classified as resistant to the disease have been re-evaluated in artificially infested soils under natural environmental conditions. The maximum disease incidence (52.6%) was reached at 26 months after planting, and the disease intensity index reached the maximum value of 38.5% at 29 months after planting. Nine breeding selections consistently confirmed the previous results regarding resistance to V. dahliae infection; however, contradictory results, compared with those of previous evaluations under controlled conditions in grow chambers, were obtained for the rest of selections tested, thereby underlining the need for long-term experimentation under natural environmental conditions. Additional positive agronomic traits, such as early bearing, were also observed for some of the resistant selections, but plant vigor varied. Some seem highly promising for release as new cultivars when characterization of other important agronomic traits is completed in the future.
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Olea , Verticillium , Ascomicetos , Fitomejoramiento , Enfermedades de las Plantas , Raíces de Plantas , Verticillium/genéticaRESUMEN
INTRODUCTION: Implantation of penile prosthesis is constantly growing but little long-term data is available concerning the associated factors of prosthesis survival. Our aim was to describe the long-term survival of penile prostheses and to identify factors influencing long-term prosthesis survival. METHODS: This is a retrospective, monocentric cohort of patients who underwent their first implantation of a penile prosthesis, between May 2000 and March 2017, at the Reims University Hospital. Prosthesis survival was calculated by the Kaplan-Meier method. A univariate and multivariate analysis to estimate the risk of surgical removal/revision of the prosthesis was performed using a Cox model. RESULTS: 150 patients were included, and 61 patients underwent surgical removal of the prosthesis (40.7%). Mean follow-up was 76.12 months (0-176 months). Prosthesis survival was 69.7% at 5 years (95% CI, 62.2-77.3) and 58.5% at 10 years (95% CI, 50.0-66.9). In multivariate analysis, the factors influencing prosthesis survival were: type of prosthesis (other vs. Coloplast TITAN®, HR 1.89, CI 95%, 1.03-3.45) and prosthesis final length (20-29cm vs. 12-17cm, HR 0.27, 95% CI, 0.09-0.77). CONCLUSION: At 10 years, the penile prosthesis survival is close to 60%. Type of implant and final length of the prosthesis may have a significant influence in long-term prosthesis survival. Patients undergoing penile prosthesis implantation must be informed about the risk of surgical removal/revision of the prosthesis. LEVEL OF EVIDENCE: 3.
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Disfunción Eréctil/cirugía , Prótesis de Pene , Falla de Prótesis , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de TiempoRESUMEN
In this work we demonstrate the capability of two gain-switched optically injected semiconductor lasers to perform high-resolution dual-comb spectroscopy. The use of low duty cycle pulse trains to gain switch the lasers, combined with optical injection, allows us to obtain flat-topped optical frequency combs with 350 optical lines (within 10 dB) spaced by 100 MHz. These frequency combs significantly improve the spectral resolution reported so far on dual-comb spectroscopy with gain-switched laser diodes. We evaluate the performance of our system by measuring the transmission profile of an absorption line of H13CN at the C-band, analyzing the attainable signal-to-noise ratio for a range of averaging times.
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In this Letter, we report a broadband frequency/polarization demultiplexer based on parallel-plate waveguides (PPWGs) for terahertz (THz) frequencies. The fabrication and experimental validation of this polarization sensitive demultiplexer is demonstrated for the range from 0.2 to 1 THz. Upgrading the demultiplexer by adding a second demultiplexer stage, a fifty-fifty amplitude splitter is also demonstrated in the same frequency range. The multiplexer is based on a stainless-steel traveling-wave antenna, exhibiting strong mechanical robustness. This unique device exhibits three splitting mechanisms in the same device: amplitude, polarization, and frequency splitting. This is a significant improvement for the next generation of THz passive components for communication purposes.
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Self-sustaining smouldering combustion (SSS) is a technology based on the flameless oxidation of an organic substrate and limited by the rate at which oxygen is diffused to the surface of the substrate. This work aims to evaluate the SSS combustion as a treatment process for the stabilization of anaerobic digestate, determining the limits of operational conditions, (moisture content (MC), air flux) that allow for a self-sustaining process. Maximum possible MC was found at 82 wt% with Darcy air flux of 50 cm/s. The digestate destruction rate (kg/(h·m2), and the addition of sand as an inert solid, to enhance the oxygen diffusion, were also investigated. A sand/substrate mass ratio of 1 allowed for SSS at 85 wt% MC, but decreased the digestate destruction rate. The average composition of the emitted gases showed ca. 25% CO and 10% H2, whereas the analysis of the ashes showed almost complete digestate inertization.
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Gases , AnaerobiosisRESUMEN
Dalbavancin is a lipoglycopeptide with potent activity against Gram-positive microorganisms, a long half-life, a favorable safety profile, and a high concentration in bone, which makes it an interesting alternative for treatment of osteoarticular infections. We performed a multicentric retrospective study of all patients with an osteoarticular infection (septic arthritis, spondylodiscitis, osteomyelitis, or orthopedic implant-related infection) treated with at least one dose of dalbavancin between 2016 and 2017 in 30 institutions in Spain. In order to evaluate the response, patients with or without an orthopedic implant were separated. A total of 64 patients were included. Staphylococcus epidermidis and Staphylococcus aureus were the most frequent microorganisms. The reasons for switching to dalbavancin were simplification (53.1%), adverse events (25%), or failure (21.9%). There were 7 adverse events, and no patient had to discontinue dalbavancin. In 45 cases, infection was related to an orthopedic implant. The implant material was retained in 23 cases, including that in 15 (65.2%) patients that were classified as cured and 8 (34.8%) that presented improvement. In 21 cases, the implants were removed, including those in 16 (76.2%) cases that were considered successes, 4 (19%) cases were considered improved, and 1 (4.8%) case that was considered a failure. Among the 19 cases without implants, 14 (73.7%) were considered cured, 3 (15.8%) were considered improved, and 2 (10.5%) were considered failures. The results show that dalbavancin is a well-tolerated antibiotic, even when >2 doses are administered, and is associated with a high cure rate. These are preliminary data with a short follow-up; therefore, it is necessary to gain more experience and, in the future, to establish the most appropriate dose and frequency.
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Huesos/microbiología , Articulaciones/microbiología , Osteomielitis/microbiología , Teicoplanina/análogos & derivados , Anciano , Femenino , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/patogenicidad , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Osteomielitis/tratamiento farmacológico , Staphylococcus aureus , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/patogenicidad , Teicoplanina/uso terapéuticoRESUMEN
We report on the experimental generation of broad and flat optical frequency combs (OFC) in a 1550 nm laser diode using gain switching with pulsed electrical excitation together with optical injection. The combination of both techniques allows the generation of high-quality OFCs at a repetition frequency of 500 MHz, showing a low-noise optical spectrum with unprecedent features in terms of width (108 tones within 10 dB) and flatness (56 tones within 3 dB) in comparison with those previously reported for this modulation frequency. The influence of the injection conditions on the OFC quality is studied. Using these two techniques, it has been possible to reduce the separation between tones, generating high spectral performance OFCs with a repetition rateof 100 MHz.
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In this paper, we numerically and experimentally demonstrate the inverse polarization effect in three-dimensional (3-D) printed polarizers for the frequency range of 0.5 - 2.7 THz. The polarizers simply consist of 3-D printed strip lines of conductive polylactic acid (CPLA, Proto-Pasta) and do not require a substrate or any further metallic deposition. The experimental and numerical results show that the proposed structure acts as a broadband polarizer between the range of 0.3 THz to 2.7 THz, in which the inverse polarization effect is clearly seen for frequencies above 0.5 THz. In the inverse polarization effect, the transmission of the transverse electric (TE) component exceeds that of the TM component, in contrast to the behavior of a typical wire-grid polarizer. We show how the performance of the polarizers depends on the spacing and thickness of the CPLA structure; extinction ratios higher than 20 dB are achieved. This is the first report using CPLA to fabricate THz polarizers, demonstrating the potential of using conductive polymers to design THz components efficiently and robustly.
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We propose a multilayer geometry to characterize thin-film samples in reflection terahertz time domain spectroscopy. Theory indicates that this geometry has higher sensitivity compared to ordinary transmission or reflection geometries when characterizing both low- and high-absorption samples. Pure water and water-ethanol mixtures are measured to verify the characterization accuracy of the proposed geometry and its capability to measure trace liquids. Paraffin-embedded oral cancer tissue is imaged to further show how the proposed geometry enhances the sensitivity for solid low-absorptive films.
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Técnicas de Preparación Histocitológica , Neoplasias de la Boca/patología , Espectroscopía de Terahertz/métodos , Agua , Humanos , Adhesión en ParafinaRESUMEN
The sufficient presence of trace elements (TE) is essential for anaerobic digestion. Barium (Ba) is considered a non-essential trace element that can be collaterally added to digesters as part of low-cost trace element sources or because of its presence in some feedstocks, such as crude glycerol. In the present study, the impact of Ba supplementation (2-2000â¯mg/L) on each stage of the anaerobic digestion (AD) process was evaluated using pure substrates (i.e., cellulose, glucose, a mixture of volatile fatty acids, sodium acetate and hydrogen) as well as a complex substrate (i.e., dried green fodder). Hydrolytic activity was affected at dosages higher than 200â¯mg Ba/L, whereas cellulose degradation was completely inhibited at 2000â¯mg Ba/L. The negative effects of the addition of Ba to methane production were observed only in the hydrolytic activity, and no effects were detected at any barium dosage in the subsequent anaerobic steps. Because Ba does not have a reported role as a cofactor of enzymes, this response could have been due to a direct inhibitory effect, a variation in the bioavailability of other trace elements, or even the availability of CO2/SO4 through precipitation as Ba-carbonates and sulphates. The results showed that the addition of Ba modified the chemical equilibrium of the studied system by varying the soluble concentration of some TEs and therefore their bioavailability. The highest variation was detected in the soluble concentration of zinc, which increased as the amount of Ba increased. Although little research has shown that Ba has some utility in anaerobic processes, its addition must be carefully monitored to avoid an undesirable modification of the chemical equilibrium in the system.
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Reactores Biológicos , Oligoelementos , Anaerobiosis , Bario , Ácidos Grasos Volátiles , MetanoRESUMEN
The potential of using rabbit manure as inoculum for biogas production was evaluated through batch assays using bean straw as substrate. The microbial diversity in the rabbit manure included lignin-degrading bacteria (classes Bacteroidia, Bacilli and Clostridia) as well as key acetoclastic (Matheanosarcina and Methanosaeta), and hydrogenotrophic (Methanobacterium, Methanolinea, and Methanovebribacter) archaea. The effects of particle size, substrate to inoculum ratio (S/X) and pH adjustment were studied to improve the inoculum activity. The adjustment of the pH entailed the highest improvement in methane production (515%) and rate (164%). However, high S/X, (3-4), resulted in the acidification of the processes, denoting an imbalance between hydrolytic bacteria and methanogenic archaea in the rabbit manure. This confirmed that the use of rabbit manure as inoculum could sustain anaerobic digestion from agricultural residues, although a proper enrichment and adaptation is necessary to ensure an appropriate methane production.