•Microbial fuel cells fed by solid organic waste.•Harsh environmental conditions in the MFC feedstock.•Power production even at very low pH and high salinity.
Twelve single chambered, air-cathode ...Tubular Microbial Fuel Cells (TMFCs) have been filled up with fruit and vegetable residues. The anodes were realized by means of a carbon fiber brush, while the cathodes were realized through a graphite-based porous ceramic disk with Nafion membranes (117 Dupont). The performances in terms of polarization curves and power production were assessed according to different operating conditions: percentage of solid substrate water dilution, adoption of freshwater and a 35mg/L NaCl water solution and, finally, the effect of an initial potentiostatic growth.
All TMFCs operated at low pH (pH=3.0±0.5), as no pH amendment was carried out. Despite the harsh environmental conditions, our TMFCs showed a Power Density (PD) ranging from 20 to 55mW/m2kgwaste and a maximum CD of 20mA/m2kgwaste, referred to the cathodic surface.
COD removal after a 28-day period was about 45%.
The remarkably low pH values as well as the fouling of Nafion membrane very likely limited TMFC performances. However, a scale-up estimation of our reactors provides interesting values in terms of power production, compared to actual anaerobic digestion plants. These results encourage further studies to characterize the graphite-based porous ceramic cathodes and to optimize the global TMFC performances, as they may provide a valid and sustainable alternative to anaerobic digestion technologies.
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•BES-mediated biofuels production and nutrient removal/recovery are summarized.•Bioelectrochemical systems are promising for recovering ammonium nitrogen.•Integration of biological ...and BES allows the development of new waste biorefineries.•Several bottlenecks that are preventing or delaying the commercialization of BES are discussed.•Conferred future challenges to develop a research interest in BESs.
Bioelectrochemical systems (BES) have the potential to be used in a variety of applications such as waste biorefinery, pollutants removal, CO2 capture, and the electrosynthesis of clean and renewable biofuels or byproducts, among others. In contrast, many technical challenges need to be addressed before BES can be scaled up and put into real-world applications. Utilizing BES, this review article presents a state-of-the-art overall view of crucial concepts and the most recent innovative results and achievements acquired from the BES system. Special attention is placed on a hybrid approach for product recovery and wastewater treatment. There is also a comprehensive overview of waste biorefinery designs that are included. In conclusion, the significant obstacles and technical concerns found throughout the BES studies are discussed, and suggestions and future requirements for the virtual usage of the BES concept in actual waste treatment are outlined.
In this paper, we tested the combined use of a biochar-based material at the cathode and of Pseudomonas aeruginosa strain in a single chamber, air cathode microbial fuel cells (MFCs) fed with a mix ...of shredded vegetable and phosphate buffer solution (PBS) in a 30% solid/liquid ratio. As a control system, we set up and tested MFCs provided with a composite cathode made up of a nickel mesh current collector, activated carbon and a single porous poly tetra fluoro ethylene (PTFE) diffusion layer. At the end of the experiments, we compared the performance of the two systems, in the presence and absence of P. aeruginosa, in terms of electric outputs. We also explored the potential reutilization of cathodes. Unlike composite material, biochar showed a life span of up to 3 cycles of 15 days each, with a pH of the feedstock kept in a range of neutrality. In order to relate the electric performance to the amount of solid substrates used as source of carbon and energy, besides of cathode surface, we referred power density (PD) and current density (CD) to kg of biomass used. The maximum outputs obtained when using the sole microflora were, on average, respectively 0.19 Wm−2kg−1 and 2.67 Wm−2kg−1, with peaks of 0.32 Wm−2kg−1 and 4.87 Wm−2kg−1 of cathode surface and mass of treated biomass in MFCs with biochar and PTFE cathodes respectively. As to current outputs, the maximum values were 7.5 Am−2 kg−1 and 35.6 Am−2kg−1 in MFCs with biochar-based material and a composite cathode. If compared to the utilization of the sole acidogenic/acetogenic microflora in vegetable residues, we observed an increment of the power outputs of about 16.5 folds in both systems when we added P. aeruginosa to the shredded vegetables. Even though the MFCs with PTFE-cathode achieved the highest performance in terms of PD and CD, they underwent a fouling episode after about 10 days of operation, with a dramatic decrease in pH and both PD and CD. Our results confirm the potentialities of the utilization of biochar-based materials in waste treatment and bioenergy production.
Marine pollution is becoming more and more serious, especially in coastal areas. Because of the sequestration and consequent accumulation of pollutants in sediments (mainly organic compounds and ...heavy metals), marine environment restoration cannot exempt from effective remediation of sediments themselves. It has been well proven that, after entering into the seawater, these pollutants are biotransformed into their metabolites, which may be more toxic than their parent molecules. Based on their bioavailability and toxic nature, these compounds may accumulate into the living cells of marine organisms. Pollutants bioaccumulation and biomagnification along the marine food chain lead to seafood contamination and human health hazards. Nowadays, different technologies are available for sediment remediation, such as physicochemical, biological, and bioelectrochemical processes. This paper gives an overview of the most recent techniques for marine sediment remediation while presenting sediment-based microbial fuel cells (SMFCs). We discuss the issues, the progress, and future perspectives of SMFC application to the removal of hydrocarbons and metals in the marine environment with concurrent energy production. We give an insight into the possible mechanisms leading to sediment remediation, SMFC energy balance, and future exploitation.
Seawater represents a potential resource to ensure sustainable availability of water for population and irrigation purposes, especially in some areas of the world. Desalination processes allow the ...production of fresh water, but they generate also brine as waste product. Sustainable brine management should be identified to ensure proper disposal and potentially resource recovery. This experimental study showed that emerging technologies such as Microbial Desalination Cells (MDCs) may provide a valuable contribution to the sustainability of the seawater desalination sector. In this paper, we report results on lab-scale desalination brine treatments applying MDCs, which allow energy savings, resource recovery, environmental impact minimization, and reduction of the organic load in municipal wastewater. Our results showed that MDCs’ treatment allows the removal of approximately 33 g of salts (62% of the total)—including chlorides, bromides, and sulphates—from 20 mL of brine within 96 h. The MDCs, according to the source of energy and the presence of mature biofilm at the anode, spent 7.2 J, 7.9 J, and 9.6 J in the desalination process, with the higher amount of energy required by the abiotic system and the lesser by the MDCs fed with just wastewater. Our approach also showed environmental and energy reductions because of potential metal recovery instead of returning them into marine environment. We quantified the avoided life cycle of human and marine eco-toxicity impacts as well as the reduction of cumulative energy demand of recovered metals. The main benefit in terms of avoided toxicity would arise from the mercury and copper recovery, while potential economic advantages would derive from the recovered cobalt that represents a strategic resource for many products such as battery storage systems.
Microbial induced calcite precipitation (MICP) offers a host of interesting features, from both theoretical and practical standpoints. This process was firstly investigated as a geo-biological ...mechanism involved in carbonate mineral formation in both rocks and soil. The interest in its practical use has significantly increased in recent years, as MICP has been used in different fields, such as oil recovery, the improvement of soil geotechnical characteristics, and concrete healing. To the best of our knowledge, this work is the first attempt to carry out a bibliometric descriptive study of publications concerning MICP. We analyzed data from the Web of Science Core Collection (WoSCC), which provides comprehensive information for bibliometric analysis, including the Science Citation Index Expanded (SCI-E) and the Social Sciences Citation Index (SSCI). The bibliometric analysis was carried out on 1580 publications, from 2000 to August 2022, and included publication output; author; institution; country; collaborations between authors, institutes, and countries; and citation frequency. We created visualization maps, including research collaborations, using the VOSviewer program. MICP, carbonate precipitation, cementation, and soil improvement in terms of geotechnical properties are frequently used keywords. Although in the year 2000, only two papers were published on MICP, the number of publications has increased rapidly since 2014. In 2021, 333 papers were published. China leads the pack as the most productive country, followed by the USA and Australia. According to our results, the number of research papers has dramatically increased in the last 5 years. MICP use for concrete healing/cementation and soil geotechnical improvement, as well as the low environmental impact of such a technique, are becoming very popular topics among researchers. With the aging of concrete buildings, as well as with the worsening of environmental pollution and soil alterations, the research regarding MICP will play an ever increasing and crucial role in civil engineering and geotechnical fields, as well as in soil science. MICP also address Sustainable Development Goal 11, “building sustainable cities and communities.” Nevertheless, our study pointed out a concentration of the MICP studies in just a few countries. Russia and Brazil, for instance, seem to poorly contribute to MICP research. Greater cooperation among countries, along with the extension of the research network on this topic, would foster more rapid progress in MICP studies, from both practical and speculative standpoints.
The need for greener processes to satisfy the demand of platform chemicals together with the possibility of reusing CO
from human activities has recently encouraged research on the set-up, ...optimization, and development of bioelectrochemical systems (BESs) for the electrosynthesis of organic compounds from inorganic carbon (CO
, HCO
). In the present study, we tested the ability of
N1-4 (DSMZ 14923) to produce acetate and D-3-hydroxybutyrate from inorganic carbon present in a CO
:N
gas mix. At the same time, we tested the ability of a
MR1 and
PA1430/CO1 consortium to provide reducing power to sustain carbon assimilation at the cathode. We tested the performance of three different systems with the same layouts, inocula, and media, but with the application of 1.5 V external voltage, of a 1000 Ω external load, and without any connection between the electrodes or external devices (open circuit voltage, OCV). We compared both CO
assimilation rate and production of metabolites (formate, acetate 3-D-hydroxybutyrate) in our BESs with the values obtained in non-electrogenic control cultures and estimated the energy used by our BESs to assimilate 1 mol of CO
. Our results showed that
NT-1 achieved the maximum CO
assimilation (95.5%) when the microbial fuel cells (MFCs) were connected to the 1000 Ω external resistor, with the
/
consortium as the only source of electrons. Furthermore, we detected a shift in the metabolism of
NT-1 because of its prolonged activity in BESs. Our results open new perspectives for the utilization of BESs in carbon capture and electrosynthesis of platform chemicals.
Central nervous system (CNS) complications during treatment of childhood acute lymphoblastic leukemia (ALL) remain a challenging clinical problem. Outcome improvement with more intensive chemotherapy ...has significantly increased the incidence and severity of adverse events. This study analyzed the incidence of neurological complications during ALL treatment in a single pediatric institution, focusing on clinical, radiological, and electrophysiological findings. Exclusion criteria included CNS leukemic infiltration at diagnosis, therapy-related peripheral neuropathy, late-onset encephalopathy, or long-term neurocognitive defects. During a 9-year period, we retrospectively collected 27 neurological events (11%) in as many patients, from 253 children enrolled in the ALL front-line protocol. CNS complications included posterior reversible leukoencephalopathy syndrome (n = 10), stroke (n = 5), temporal lobe epilepsy (n = 2), high-dose methotrexate toxicity (n = 2), syndrome of inappropriate antidiuretic hormone secretion (n = 1), and other unclassified events (n = 7). In conclusion, CNS complications are frequent events during ALL therapy, and require rapid detection and prompt treatment to limit permanent damage.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Introduction
Tuberous sclerosis complex (TSC) is a rare autosomal dominant disorder affecting multiple systems, due to inactivating mutations of TSC1 or TSC2 mTOR pathway genes. Neurological ...manifestations are observed in about 95% cases, representing the most frequent cause of morbidity and one of the most common causes of mortality.
Background
Neuroimaging is crucial for early diagnosis, monitoring, and management of these patients. While computed tomography is generally used as first-line investigation at emergency department, magnetic resonance imaging is the reference method to define central nervous system involvement and investigate subtle pathophysiological alterations in TSC patients.
Purpose
Here, we review the state-of-the-art knowledge in TSC brain imaging, describing conventional findings and depicting the role of advanced techniques in providing new insights on the disease, also offering an overview on future perspectives of neuroimaging applications for a better understanding of disease pathophysiology.
Background
Brain parenchyma (BP) and intracranial cerebrospinal fluid (iCSF) volumes measured by fully automated segmentation of clinical brain MRI studies may be useful for the diagnosis and ...follow‐up of pediatric hydrocephalus. However, previously published segmentation techniques either rely on dedicated sequences, not routinely used in clinical practice, or on spatial normalization, which has limited accuracy when severe brain distortions, such as in hydrocephalic patients, are present.
Purpose
We developed a fully automated method to measure BP and iCSF volumes from clinical brain MRI studies of pediatric hydrocephalus patients, exploiting the complementary information contained in T2‐ and T1‐weighted images commonly used in clinical practice.
Methods
The proposed procedure, following skull‐stripping of the combined volumes, performed using a multiparametric method to obtain a reliable definition of the inner skull profile, maximizes the CSF‐to‐parenchyma contrast by dividing the T2w‐ by the T1w‐ volume after full‐scale dynamic rescaling, thus allowing separation of iCSF and BP through a simple thresholding routine.
Results
Validation against manual tracing on 23 studies (four controls and 19 hydrocephalic patients) showed excellent concordance (ICC > 0.98) and spatial overlap (Dice coefficients ranging from 77.2% for iCSF to 96.8% for intracranial volume). Accuracy was comparable to the intra‐operator reproducibility of manual segmentation, as measured in 14 studies processed twice by the same experienced neuroradiologist. Results of the application of the algorithm to a dataset of 63 controls and 57 hydrocephalic patients (19 with parenchymal damage), measuring volumes’ changes with normal development and in hydrocephalic patients, are also reported for demonstration purposes.
Conclusions
The proposed approach allows fully automated segmentation of BP and iCSF in clinical studies, also in severely distorted brains, enabling to assess age‐ and disease‐related changes in intracranial tissue volume with an accuracy comparable to expert manual segmentation.
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