In many applications, complex biological phenomena can be reproduced via structured mathematical models, which depend on numerous biotic and abiotic input parameters, whose effect on model outputs can be of paramount importance. The calibration of model parameters is crucial to obtain the best fit between simulated and experimental data. Sensitivity analysis and uncertainty quantification constitute essential tools in the field of biological systems modeling.
View Article and Find Full Text PDFAn original mathematical model describing the photo fermentation process is proposed. The model represents the first attempt to describe the photo fermentative hydrogen production and polyhydroxybutyrate accumulation, simultaneously. The mathematical model is derived from mass balance principles and consists of a system of ordinary differential equations describing the biomass growth, the nitrogen and the substrate degradation, the hydrogen and other catabolites production, and the polyhydroxybutyrate accumulation in photo fermentation systems.
View Article and Find Full Text PDFMicrofiltration is a widely used engineering technology for fresh water production and water treatment. The major concern in many applications is the formation of a biological fouling layer leading to increased hydraulic resistance and flux decline during membrane operations. The growth of bacteria constituting such a biological layer implicates the formation of a multispecies biofilm and the consequent increase of operational costs for reactor management and cleaning procedures.
View Article and Find Full Text PDFThe use of biological processes for the treatment of asbestos cement waste (ACW) has gained interest in recent years. Nevertheless, this methodology is not yet consolidated because of the incomplete ACW conversion during the biological treatment and the consequent need for further treatments that generally require a high amount of energy and chemicals. In this study, the efficiency of both mesophilic and thermophilic dark fermentation (DF) fed with glucose in fed-batch conditions was assessed for ACW biological treatment.
View Article and Find Full Text PDFIn this work, an original mathematical model for metals leaching from electronic waste in a dark fermentation process is proposed. The kinetic model consists of a system of non-linear ordinary differential equations, accounting for the main biological, chemical, and physical processes occurring in the fermentation of soluble biodegradable substrates and in the dissolution process of metals. Ad-hoc experimental activities were carried out for model calibration purposes, and all experimental data were derived from specific lab-scale tests.
View Article and Find Full Text PDFThe paper is a preliminary study on the selection of lactic acid producing microorganisms from a mixed microbial population via bioaugmentation. The bioaugmentation technique is based on pH sudden variations occurring in sequential batch steps of a dark fermentation process applied to simple substrates. Different conditions are tested and compared.
View Article and Find Full Text PDFThe paper investigates the phenomenon of Carbon Catabolite Repression occurring during photo fermentation of ethanol-rich effluents, which usually contain ethanol as main carbon source, and glycerol as secondary one. The study was conducted using mixed phototrophic cultures, adopting, as substrate, the effluent produced by the alcoholic fermentation of sugar cane bagasse. In order to elucidate the phenomenon, experimental tests were carried out using two different ethanol to glycerol ratios.
View Article and Find Full Text PDFThis work aims at analyzing and comparing the different modeling approaches used to date to simulate, design and control photo fermentation processes for hydrogen production and/or wastewater treatment. The study is directed to researchers who approach the problem of photo fermentation mathematical modeling. It is a useful tool to address future research in this specific field in order to overcome the difficulty of modeling a complex, not totally elucidate process.
View Article and Find Full Text PDFBiohythane (hydrogen + methane) production in a two stage dark fermentation (DF) and anaerobic digestion (AD) process from food waste (FW) has been studied. This paper investigated the effect of operation temperature, i.e.
View Article and Find Full Text PDFBackground: The use of knee braces early after anterior cruciate ligament (ACL) reconstruction is a controversial issue. The study preliminarily compares the effect of a traditional brace blocked in knee extension and a new functional brace equipped with a spring resistance on walking and strength performance early after ACL reconstruction performed in the acute/subacute stage.
Methods: 14 ACL-reconstructed patients wore either a traditional (Control group: CG, 7 subjects) or a new functional brace (Experimental group: EG 7 subjects) until the 30 post-operative day.
The applicability and convenience of biohydrogen and poly-β-hydroxybutyrate production through single-stage photofermentation of winery wastewater is demonstrated in the present study. Experiments are conducted using a purple non-sulfur bacteria mixed consortium, subject to variable nutrient conditions, to analyze the effect of initial chemical oxygen demand and the available nitrogen source on the metabolic response. Results show that winery wastewater is a promising substrate for photofermentation processes, despite the presence of inhibiting compounds such as phenolics.
View Article and Find Full Text PDFThis study compared the binding of europium by soil and aquatic natural organic matter (NOM) exemplified by Pahokee Peat humic acid (PPHA) and Northern Reservoir NOM, respectively. NOM/Eu interactions were measured based on the differential absorbance approach. The experimental results show that the binding of Eu by humic acid isolated from agricultural soil results in several features of the differential spectra that are distinct from those observed for aquatic NOM.
View Article and Find Full Text PDFAn original mechanistic model able to describe the fate of trace elements (TE) in anaerobic digestion systems has been synthetized from mass balance equations. The model takes into account the main biochemical and physico-chemical processes affecting TE bioavailability and it is aimed at evaluating the effect that the combination of such processes exerts on the system performance. Five main modules have been introduced: biochemistry, physico-chemistry, sorption, complexation and precipitation.
View Article and Find Full Text PDFA mathematical model to simulate the biological processes occurring in a membrane bioreactor (MBR) is presented. The model accounts for different MBR technical features by introducing specific permeability parameters for the applied membrane system. The model considers for the heterotrophic storage process and the formation of soluble microbial products.
View Article and Find Full Text PDFIn this paper, the treatment of asbestos-cement waste (ACW) has been attempted by a dark fermentation (DF) pre-treatment followed by hydrothermal and anaerobic digestion (AD) treatments. During DF, glucose, employed as a biodegradable substrate, was mainly converted to H-rich biogas and organic acids (OAs). The latter caused the dissolution of the cement matrix and the partial structural collapse of chrysotile (white asbestos).
View Article and Find Full Text PDFThe interest in microalgae for wastewater treatment and liquid bio-fuels production (i.e. biodiesel and bioethanol) is steadily increasing due to the energy demand of the ultra-modern technological world.
View Article and Find Full Text PDFThe present work studied the start-up process of a mesophilic (37 ± 2 °C) anaerobic fluidized bed reactor (AFBR) operated at a hydraulic retention time (HRT) of 20 days using synthetic carbohydrate rich wastewater. Anox Kaldness-K1 carriers were used as biofilm carrier material. The reactor performance and biofilm formation were evaluated during the process.
View Article and Find Full Text PDFInt J Immunogenet
February 2014
In this report, we describe the identification and sequencing of a novel HLA-DPB1 allele, found in an Italian haematological patient. This allele is identical to DPB1*17:01 except for a single nucleotide substitution (GAC→GAG) at position 57, which changes the encoded amino acid from Asp to Glu.
View Article and Find Full Text PDFParoxysmal nocturnal haemoglobinuria (PNH) is a haematopoietic disorder characterized by expansion of phosphatidylinositol glycan-A-defective progenitor(s). Immune-dependent mechanisms, likely involving a deranged T cell-dependent autoimmune response, have been consistently associated with the selection/dominance of PNH precursors. Natural killer (NK) lymphocytes might participate in PNH pathogenesis, but their role is still controversial.
View Article and Find Full Text PDFInt J Immunogenet
October 2010
We describe a novel HLA-B*51 allele detected by DNA direct sequencing. The sequence of this allele has been officially named B*51:78 as a confirmatory sequence. This new allele nucleotide sequence differs from HLA-B*51:01:01 for two point mutations in exon 2 where codons 79-80 change from CGG-ATC to CGC-ACC (p.
View Article and Find Full Text PDFSummary Here, we describe the characterisation of a new allelic variant of HLA-B*57. The novel allele, HLA-B*5728N, was identified with sequence-based typing in a Caucasoid family. HLA-B*5728N, differs from HLA-B*5701 because of a nucleotide substitution at position 420 (C->G) resulting in a coding change from Tyrosine to a stop codon.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
May 2005
The plasma peptide component (PPC) from ten melanoma (Mel), breast cancer (BC) and healthy individuals was examined by a combination of RP-HPLC, surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) and tandem mass spectrometry. A three peak pattern (2023, 2039, 2053.5 m/z) was primarily observed in melanoma.
View Article and Find Full Text PDFThe current study focuses the analysis on the possible relationship between HLA allele frequency and clinical outcome of melanoma in a population of 382 Italian patients, as compared with 203 ethnically matched controls. In a 3-year follow-up study, results showed significant differences between groups of patients selected according to clinical stage, histology, and progression of the disease. A*01 seems to be correlated with a less aggressive variant of the disease, whereas DRB1*01-DQB1*0501 seems to be associated with metastatic progression of melanoma.
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