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Biomass gasification is a thermochemical process that produces a gaseous end product known as syngas, the main components of which are CO, CO2, and H2. Starting from syngas it is possible to upgrade this mixture into Synthetic Natural Gas (SNG) through a catalytic methanation process. In this work, a thermodynamic study was conducted to see how operative parameters such as the temperature of the methanation reactor, the quality of the syngas (related to different gasification technologies), and the presence of a conditioning stage based on water gas shift reaction, can influence the output variables as the conversion degree of the reactants, the mass yield and the low heating value of the final products.

Tissue-engineered skin substitutes are promising tools to cover large and deep skin defects. However, the lack of a synergic and fast regeneration of the vascular network, nerves, and skin appendages limits complete skin healing and impairs functional recovery. It has been highlighted that an ideal skin substitute should mimic the structure of the native tissue to enhance clinical effectiveness. Here, we produced a pre-vascularized dermis (PVD) comprised of fibroblasts embedded in their own extracellular matrix (ECM) and a capillary-like network. Upon implantation in a mouse full-thickness skin defect model, we observed a very early innervation of the graft in 2 weeks. In addition, mouse capillaries and complete epithelialization were detectable as early as 1 week after implantation and, skin appendages developed in 2 weeks. These anatomical features underlie the interaction with the skin nerves, thus providing a further cue for reinnervation guidance. Further, the graft displays mechanical properties, collagen density, and assembly features very similar to the host tissue. Taken together our data show that the pre-existing ECM components of the PVD, physiologically organized and assembled similarly to the native tissue, support a rapid regeneration of dermal tissue. Therefore, our results suggest a promising potential for PVD in skin regeneration.

Abstract Three-dimensional hydrogel-based organ-like cultures can be applied to study development, regeneration, and disease in vitro. However, the control of engineered hydrogel composition, mechanical properties and geometrical constraints tends to be restricted to the initial time of fabrication. Modulation of hydrogel characteristics over time and according to culture evolution is often not possible. Here, we overcome these limitations by developing a hydrogel-in-hydrogel live bioprinting approach that enables the dynamic fabrication of instructive hydrogel elements within pre-existing hydrogel-based organ-like cultures. This can be achieved by crosslinking photosensitive hydrogels via two-photon absorption at any time during culture. We show that instructive hydrogels guide neural axon directionality in growing organotypic spinal cords, and that hydrogel geometry and mechanical properties control differential cell migration in developing cancer organoids. Finally, we show that hydrogel constraints promote cell polarity in liver organoids, guide small intestinal organoid morphogenesis and control lung tip bifurcation according to the hydrogel composition and shape.

An innovative process layout for sludge waste management based on chemical looping combustion and flue gas methanation is analyzed in this work. The technical performance of the system was assessed by considering that the flue gas is first purified and then mixed with a pure hydrogen stream sourced from an array of electrolysis cells to produce methane. The life cycle assessment (LCA) and life cycle cost (LCC) methodologies were applied to quantify the environmental and economic performances of the proposed process, and a hotspot analysis was carried out to recognize its most critical steps. The proposed system was then compared with a reference system that includes both the conventional waste management pathways for the Italian context and methane production. Finally, to account for the variability in the future economic climate, the effects of changes in landfill storage costs on sewage end-of-life costs for both the proposed and reference systems were evaluated. With respect to 1 kg/h of sewage sludge with 10%wt of humidity, the analysis shows that the proposed system (i) reduces landfill wastes by about 68%, (ii) has an end-of-life cost of 1.75 EUR × kg−1, and (iii) is environmentally preferable to conventional sewage sludge treatment technologies with respect to several impact categories.

The extracellular microenvironment regulates cell decisions through the accurate presentation at the cell surface of a complex array of biochemical and biophysical signals that are mediated by the structure and composition of the extracellular matrix (ECM). On the one hand, the cells actively remodel the ECM, which on the other hand affects cell functions. This cell–ECM dynamic reciprocity is central in regulating and controlling morphogenetic and histogenetic processes. Misregulation within the extracellular space can cause aberrant bidirectional interactions between cells and ECM, resulting in dysfunctional tissues and pathological states. Therefore, tissue engineering approaches, aiming at reproducing organs and tissues in vitro, should realistically recapitulate the native cell–microenvironment crosstalk that is central for the correct functionality of tissue-engineered constructs. In this review, we will describe the most updated bioengineering approaches to recapitulate the native cell microenvironment and reproduce functional tissues and organs in vitro. We have highlighted the limitations of the use of exogenous scaffolds in recapitulating the regulatory/instructive and signal repository role of the native cell microenvironment. By contrast, strategies to reproduce human tissues and organs by inducing cells to synthetize their own ECM acting as a provisional scaffold to control and guide further tissue development and maturation hold the potential to allow the engineering of fully functional histologically competent three-dimensional (3D) tissues.

Abstract The production of skeletal muscle constructs useful for replacing large defects in vivo, such as in congenital diaphragmatic hernia (CDH), is still considered a challenge. The standard application of prosthetic material presents major limitations, such as hernia recurrences in a remarkable number of CDH patients. With this work, we developed a tissue engineering approach based on decellularized diaphragmatic muscle and human cells for the in vitro generation of diaphragmatic-like tissues as a proof-of-concept of a new option for the surgical treatment of large diaphragm defects. A customized bioreactor for diaphragmatic muscle was designed to control mechanical stimulation and promote radial stretching during the construct engineering. In vitro tests demonstrated that both ECM remodeling and fibroblast overgrowth were positively influenced by the bioreactor culture. Mechanically stimulated constructs also increased tissue maturation, with the formation of new oriented and aligned muscle fibers. Moreover, after in vivo orthotopic implantation in a surgical CDH mouse model, mechanically stimulated muscles maintained the presence of human cells within myofibers and hernia recurrence did not occur, suggesting the value of this approach for treating diaphragm defects.

Skeletal muscle is a dynamic tissue in which homeostasis and function are guaranteed by a very defined three-dimensional organization of myofibers in respect to other non-muscular components, including the extracellular matrix and the nervous network. In particular, communication between myofibers and the nervous system is essential for the overall correct development and function of the skeletal muscle. A wide range of chronic, acute and genetic-based human pathologies that lead to the alteration of muscle function are associated with modified preservation of the fine interaction between motor neurons and myofibers at the neuromuscular junction. Recent advancements in the development of in vitro models for human skeletal muscle have shown that three-dimensionality and integration of multiple cell types are both key parameters required to unveil pathophysiological relevant phenotypes. Here, we describe recent achievement reached in skeletal muscle modeling which used biomaterials for the generation of three-dimensional constructs of myotubes integrated with motor neurons.

Abstract Patients affected by chronic kidney disease (CKD) have an increased risk of developing cognitive impairment. The cause of mental health disorders in CKD and in chronic hemodialysis patients is multifactorial, due to the interaction of classical cardiovascular disease risk factors, kidney- and dialysis-related risk factors with depression, and multiple drugs overuse. A large number of compounds, defined as uremic toxins that normally are excreted by healthy kidneys, accumulate in the circulations, in the tissues, and in the organs of CKD patients. Among the candidate uremic toxins are several guanidino compounds, such as Guanidine. Uremic toxins may also accumulate in the brain and may have detrimental effects on cerebral resident cells (neurons, astrocytes, microglia) and microcirculation. The present study aims to analyze the effect of Guanidine on hippocampal excitatory postsynaptic field potentials (fEPSPs) and in CA1 pyramidal neurons recorded intracellularly. Moreover, we compared these effects with the alterations induced in vitro by CKD patients derived serum samples. Our results show an increased, dose-dependent, synaptic activity in the CA1 area in response to both synthetic Guanidine and patient’s serum, through a mechanism involving glutamatergic transmission. In particular, the concomitant increase of both NMDA and AMPA component of the excitatory postsynaptic currents (EPSCs) suggests a presynaptic mechanism. Interestingly, in presence of the lower dose of guanidine, we measure a significant reduction of EPSCs, in fact the compound does not inhibit GABA receptors allowing their inhibitory effect of glutamate release. These findings suggest that cognitive symptoms induced by the increase of uremic compounds in the serum of CKD patients are caused, at least in part, by an increased glutamatergic transmission in the hippocampus.

The human developmental processes during the early post-implantation stage instruct the specification and organization of the lineage progenitors into a body plan. These processes, which include patterning, cell sorting, and establishment of the three germ layers, have been classically studied in non-human model organisms and only recently, through micropatterning technology, in a human-specific context. Micropatterning technology has unveiled mechanisms during patterning and germ layer specification; however, cell sorting and their segregation in specific germ layer combinations have not been investigated yet in a human-specific in vitro system. Here, we developed an in vitro model of human ectodermal patterning, in which human pluripotent stem cells (hPSCs) self-organize to form a radially regionalized neural and non-central nervous system (CNS) ectoderm. We showed that by using micropatterning technology and by modulating BMP and WNT signals, we can regulate the appearance and spatial distribution of the different ectodermal populations. This pre-patterned ectoderm can be used to investigate the cell sorting behavior of hPSC-derived meso-endoderm cells, with an endoderm that segregates from the neural ectoderm. Thus, the combination of micro-technology with germ layer cross-mixing enables the study of cell sorting of different germ layers in a human context.

Crude bio-oil obtained from fast pyrolysis of biomass and wastes is typically characterised by the presence of high levels of oxygenated compounds, which are mainly responsible for its unfavourable characteristics (e.g., low heating value, high acidity, and poor storage stability). In order to overcome this drawback and favourably produce drop-in fuels, the fast pyrolysis of olive stone (OS), has been studied by giving particular attention to the exploration of operating conditions (i.e. pyrolysis temperature) and strategies (i.e. catalytic pyrolysis and co-pyrolysis) suitable to promote efficient de-oxygenation of bio-oils and improve the quality of the product streams. Steady state fast pyrolysis tests were performed in a bench scale fluidized bed reactor (gas residence time ~1s). Pyrolysis tests were carried out at 500 °C and 600 °C by using either inert sand or ?-alumina catalyst as bed material. Outcomes from the non-catalytic and the catalytic co-pyrolysis of low-density polyethylene (LDPE) and OS (plastic-to-biomass ratio of 20/80) at two different temperatures (500 and 600 °C) are also presented. Preliminary findings highlight that the co-processing of LDPE and OS under non-catalytic conditions stands out for the formation of long-chain aliphatic hydrocarbons in the form of both liquid paraffins and wax deposits, which are well-known to be the primary products evolved from the pyrolysis of polyolefins. The addition of ?-alumina catalyst significantly affects both the distribution and the quality of the pyrolytic products (char, bio-oils, and gas). Under catalytic co-pyrolysis conditions, a marked reduction in the yield of bio-liquid is observed, compensated by a remarkable improvement in its quality, particularly in terms of the formation of light mono-aromatics and a marked decrease in the total amount of the oxygenated compounds. On the downside, however, a significant increase in the production of polycyclic aromatic hydrocarbons (PAHs) is detected. Remarkable benefits are also detected by increasing the co-pyrolysis temperature to 600 °C, particularly in terms of content of oxygenated compounds in the bio-oils, as well as in terms of PAHs and water formation, which decreased considerably. Altogether, preliminary findings of this study suggest that further research efforts are required in order to improve the process performance, for example by optimizing the operating conditions as well as the physicochemical properties of catalysts.

A viable solution for residual biomass exploitation to reduce the cost related to biomass disposal and simultaneously create profit by electrical and thermal energy use is combined heat and power generation over the micro-scale of power (m-CHP) based on biomass gasification. The exploitation and improvement of these systems were the main objectives of the Italian project “PROMETEO – Production of electrical, thermal and cooling energy with m-CHP fueled by residual biomass”, funded by the local Ministry of Economic Development (MISE). The present work shows an extended experimental activity based on a 20kW micro-cogeneration system as powered by two types of residual lignocellulosic biomasses briquettes in a demonstrative environment site identified in a waste management and storage plant in the Municipality of Mugnano, Naples, in the south of Italy. The m-CHP plant is made of a gasifier, a syngas cleaning circuit and a spark ignition (SI) internal combustion engine (ICE) connected to an electric-generator. The electrical output was meant to power the plant machines for the operations of waste storage. For both biomasses, tests were conducted for the complete characterization of the system in low and medium load and in different spark ignition timing to assess the system sensitivity. The m-CHP performance was investigated with a complete characterization of the syngas and tar compositions, main pollutant emissions and internal combustion engine analyses, aimed at the evaluation of the energetic and environmental efficiencies. An analysis of the air quality near the site by evaluating CO, O3, NO2, C6H6 and PM10 concentration was also carried out. The ultimate purpose of the present work is the demonstration of the advantages of the employment of biomass-powered cogeneration systems in the Mediterranean regions.

Abstract Skeletal muscle decellularization allows the generation of natural scaffolds that retain the extracellular matrix (ECM) mechanical integrity, biological activity, and three‐dimensional (3D) architecture of the native tissue. Recent reports showed that in vivo implantation of decellularized muscles supports muscle regeneration in volumetric muscle loss models, including nervous system and neuromuscular junctional homing. Since the nervous system plays pivotal roles during skeletal muscle regeneration and in tissue homeostasis, support of reinnervation is a crucial aspect to be considered. However, the effect of decellularized muscles on reinnervation and on neuronal axon growth has been poorly investigated. Here, we characterized residual protein composition of decellularized muscles by mass spectrometry and we show that scaffolds preserve structural proteins of the ECM of both skeletal muscle and peripheral nervous system. To investigate whether decellularized scaffolds could per se attract neural axons, organotypic sections of spinal cord were cultured three dimensionally in vitro, in presence or in absence of decellularized muscles. We found that neural axons extended from the spinal cord are attracted by the decellularized muscles and penetrate inside the scaffolds upon 3D coculture. These results demonstrate that decellularized scaffolds possess intrinsic neurotrophic properties, supporting their potential use for the treatment of clinical cases where extensive functional regeneration of the muscle is required.

Refuse-Derived Fuels (RDFs) are segregated forms of wastes obtained by a combined mechanical–biological processing of municipal solid wastes (MSWs). The narrower characteristics, e.g., high calorific value (18–24 MJ/kg), low moisture content (3–6%) and high volatile (77–84%) and carbon (47–56%) contents, make RDFs more suitable than MSWs for thermochemical valorization purposes. As a matter of fact, EU regulations encourage the use of RDF as a source of energy in the frameworks of sustainability and the circular economy. Pyrolysis and gasification are promising thermochemical processes for RDF treatment, since, compared to incineration, they ensure an increase in energy recovery efficiency, a reduction of pollutant emissions and the production of value-added products as chemical platforms or fuels. Despite the growing interest towards RDFs as feedstock, the literature on the thermochemical treatment of RDFs under pyrolysis and gasification conditions still appears to be limited. In this work, results on pyrolysis and gasification tests on a real RDF are reported and coupled with a detailed characterization of the gaseous, condensable and solid products. Pyrolysis tests have been performed in a tubular reactor up to three different final temperatures (550, 650 and 750 °C) while an air gasification test at 850 °C has been performed in a fluidized bed reactor using sand as the bed material. The results of the two thermochemical processes are analyzed in terms of yield, characteristics and quality of the products to highlight how the two thermochemical conversion processes can be used to accomplish waste-to-materials and waste-to-energy targets. The RDF gasification process leads to the production of a syngas with a H2/CO ratio of 0.51 and a tar concentration of 3.15 g/m3.

The healing of deep skin wounds is a complex phenomenon evolving according with a fine spatiotemporal regulation of different biological events (hemostasis, inflammation, proliferation, remodeling). Due to the spontaneous evolution of damaged human dermis toward a fibrotic scar, the treatment of deep wounds still represents a clinical concern. Bioengineered full-thickness skin models may play a crucial role in this direction by providing a deep understanding of the process that leads to the formation of fibrotic scars. This will allow (i) to identify new drugs and targets/biomarkers, (ii) to test new therapeutic approaches, and (iii) to develop more accurate in silico models, with the final aim to guide the closure process toward a scar-free closure and, in a more general sense, (iv) to understand the mechanisms involved in the intrinsic and extrinsic aging of the skin. In this work, the complex dynamic of events underlaying the closure of deep skin wound is presented and the engineered models that aim at replicating such complex phenomenon are reviewed. Despite the complexity of the cellular and extracellular events occurring during the skin wound healing the gold standard assay used to replicate such a process is still represented by planar in vitro models that have been largely used to identify the key factors regulating the involved cellular processes. However, the lack of the main constituents of the extracellular matrix (ECM) makes these over-simplistic 2D models unable to predict the complexity of the closure process. Three-dimensional bioengineered models, which aim at recreating the closure dynamics of the human dermis by using exogenous biomaterials, have been developed to fill such a gap. Although interesting mechanistic effects have been figured out, the effect of the inflammatory response on the ECM remodelling is not replicated yet. We discuss how more faithful wound healing models can be obtained by creating immunocompetent 3D dermis models featuring an endogenous ECM.

Intestine-Liver-on-chip systems can be useful to predict oral drug administration and first-pass metabolism in vitro in order to partly replace the animal model. While organ-on-chip technology can count on sophisticated micro-physiological devices, the engineered organs still remain artificial surrogates of the native counterparts. Here, we used a bottom-up tissue engineering strategy to build-up physiologically functional 3D Human Intestine Model (3D-HIM) as well as 3D Liver-microtissues (HepG2-μTPs) in vitro and designed a microfluidic Intestine-Liver-On-Chip (InLiver-OC) to emulate first-pass mechanism occurring in vivo. Our results highlight the ethanol-induced 3D-HIM hyper-permeability and stromal injury, the intestinal prevention on the liver injury, as well as the synergic contribution of the two 3D tissue models on the release of metabolic enzymes after high amount of ethanol administration.

The reproduction of reliable in vitro models of human skeletal muscle is made harder by the intrinsic 3D structural complexity of this tissue. Here we coupled engineered hydrogel with 3D structural cues and specific mechanical properties to derive human 3D muscle constructs ("myobundles") at the scale of single fibers, by using primary myoblasts or myoblasts derived from embryonic stem cells. To this aim, cell culture was performed in confined, laminin-coated micrometric channels obtained inside a 3D hydrogel characterized by the optimal stiffness for skeletal muscle myogenesis. Primary myoblasts cultured in our 3D culture system were able to undergo myotube differentiation and maturation, as demonstrated by the proper expression and localization of key components of the sarcomere and sarcolemma. Such approach allowed the generation of human myobundles of ~10 mm in length and ~120 μm in diameter, showing spontaneous contraction 7 days after cell seeding. Transcriptome analyses showed higher similarity between 3D myobundles and skeletal signature, compared to that found between 2D myotubes and skeletal muscle, mainly resulting from expression in 3D myobundles of categories of genes involved in skeletal muscle maturation, including extracellular matrix organization. Moreover, imaging analyses confirmed that structured 3D culture system was conducive to differentiation/maturation also when using myoblasts derived from embryonic stem cells. In conclusion, our structured 3D model is a promising tool for modelling human skeletal muscle in healthy and diseases conditions.

Organ on chip (OOC) has emerged as a major technological breakthrough and distinct model system revolutionizing biomedical research and drug discovery by recapitulating the crucial structural and functional complexity of human organs in vitro. OOC are rapidly emerging as powerful tools for oncology research. Indeed, Cancer on chip (COC) can ideally reproduce certain key aspects of the tumor microenvironment (TME), such as biochemical gradients and niche factors, dynamic cell–cell and cell–matrix interactions, and complex tissue structures composed of tumor and stromal cells. Here, we review the state of the art in COC models with a focus on the microphysiological systems that host multicellular 3D tissue engineering models and can help elucidate the complex biology of TME and cancer growth and progression. Finally, some examples of microengineered tumor models integrated with multi-organ microdevices to study disease progression in different tissues will be presented.

Combining decellularised scaffolds with patient-derived cells holds promise for bioengineering of functional tissues. Here the authors develop a two-stage approach to engineer an oesophageal graft that retains the structural organisation of native oesophagus.

Abstract Pathological conditions affecting skeletal muscle function may lead to irreversible volumetric muscle loss (VML). Therapeutic approaches involving acellular matrices represent an emerging and promising strategy to promote regeneration of skeletal muscle following injury. Here we investigated the ability of three different decellularised skeletal muscle scaffolds to support muscle regeneration in a xenogeneic immune-competent model of VML, in which the EDL muscle was surgically resected. All implanted acellular matrices, used to replace the resected muscles, were able to generate functional artificial muscles by promoting host myogenic cell migration and differentiation, as well as nervous fibres, vascular networks, and satellite cell (SC) homing. However, acellular tissue mainly composed of extracellular matrix (ECM) allowed better myofibre three-dimensional (3D) organization and the restoration of SC pool, when compared to scaffolds which also preserved muscular cytoskeletal structures. Finally, we showed that fibroblasts are indispensable to promote efficient migration and myogenesis by muscle stem cells across the scaffolds in vitro. This data strongly support the use of xenogeneic acellular muscles as device to treat VML conditions in absence of donor cell implementation, as well as in vitro model for studying cell interplay during myogenesis.

Decellularized skeletal muscle (dSkM) constructs have received much attention in recent years due to the versatility of their applications in vitro. In search of adequate in vitro models of the skeletal muscle tissue, the dSkM offers great advantages in terms of the preservation of native-tissue complexity, including three-dimensional organization, the presence of residual signaling molecules within the construct, and their myogenic and neurotrophic abilities. Here, we attempted to develop a 3D model of neuromuscular tissue. To do so, we repopulated rat dSkM with human primary myogenic cells along with murine fibroblasts and we coupled them with organotypic rat spinal cord samples. Such culture conditions not only maintained multiple cell type viability in a long-term experimental setup, but also resulted in functionally active construct capable of contraction. In addition, we have developed a customized culture system which enabled easy access, imaging, and analysis of in vitro engineered co-cultures. This work demonstrates the ability of dSkM to support the development of a contractile 3D in vitro model of neuromuscular tissue fit for long-term experimental evaluations.

Transdermal drug delivery represents an appealing alternative to conventional drug administration systems. In fact, due to their high patient compliance, the development of dissolvable and biodegradable polymer microneedles has recently attracted great attention. Although stamp-based procedures guarantee high tip resolution and reproducibility, they have long processing times, low levels of system engineering, are a source of possible contaminants, and thermo-sensitive drugs cannot be used in conjunction with them. In this work, a novel stamp-based microneedle fabrication method is proposed. It provides a rapid room-temperature production of multi-compartmental biodegradable polymeric microneedles for controlled intradermal drug release. Solvent casting was carried out for only a few minutes and produced a short dissolvable tip made of polyvinylpyrrolidone (PVP). The rest of the stamp was then filled with degradable poly(lactide-co-glycolide) (PLGA) microparticles (μPs) quickly compacted with a vapor-assisted plasticization. The outcome was an array of microneedles with tunable release. The ability of the resulting microneedles to indent was assessed using pig cadaver skin. Controlled intradermal delivery was demonstrated by loading both the tip and the body of the microneedles with model therapeutics; POXA1b laccase from Pleurotus ostreatus is a commercial enzyme used for the whitening of skin spots. The action and indentation of the enzyme-loaded microneedle action were assessed in an in vitro skin model and this highlighted their ability to control the kinetic release of the encapsulated compound.

The intestine is a highly heterogeneous hollow organ with biological, mechanical and chemical differences between lumen and wall. A functional human intestine model able to recreate the in vivo dynamic nature as well as the native tissue morphology is demanded for disease research and ​drug discovery. Here, we present a system, which combines an engineered three-dimensional (3D) tubular-shaped intestine model (3D In-tube) with a custom-made microbioreactor to impart the key aspects of the in vivo microenvironment of the human intestine, mimicking the rhythmic peristaltic movement. We adapted a previously established bottom-up tissue engineering approach, to produce the 3D tubular-shaped lamina propria and designed a glass microbioreactor to induce the air–liquid interface ​condition and peristaltic-like motion. Our results demonstrate the production of a villi-like protrusion and a correct spatial differentiation of the intestinal epithelial cells in enterocyte-like as well as mucus-producing-like cells on the lumen side of the 3D In-tube. This dynamic platform offers a proof-of-concept model of the human intestine. Keywords: 3D engineered tubular-shaped intestine model, Air--liquid interface, Peristaltic-like motion, Extracellular matrix, Microbioreactor

La conjunción de humedales costeros y continentales en zonas semiáridas y en adyacencias urbanas, representa un valioso patrimonio socio-ambiental, sujeto a las tensiones que la expansión urbana genera, especialmente si se manifiesta con altas tasas de crecimiento. El presente artículo aborda el problema de los cambios físicos sobre humedales provocados por la expansión urbana acelerada en el contexto mencionado, identificando factores agravantes. Se estudió el caso de Río Grande, ciudad costera de la estepa de Tierra del Fuego, Argentina, cuyo crecimiento fue impulsado desde 1972 por políticas de promoción industrial. Los humedales fueron identificados, clasificados y cartografiados mediante análisis multiespectral de imágenes de satélite. La expansión urbana se delimitó según tres períodos vinculados a variantes en las políticas de promoción. El análisis espacio-temporal evidencia correspondencia entre pulsos de fluctuación de las políticas, con la dinámica de la expansión urbana y ocupación de áreas naturales. Un tercio de la expansión urbana fue a expensas de la desaparición de humedales, con saldo adicional de unidades fragmentadas. Se analizan externalidades, no siempre evidentes, resultantes de la urbanización de estos ecosistemas y se concluye en la significación de los asentamientos informales, así como la falta de planificación como factores que incrementan la pérdida de humedales.

Fatigue is still present in up to 40–50% of kidney transplant recipients (KTR), the results of studies comparing the prevalence among patients on hemodialysis (HD) and KTR led to conflicting results. Fatigue correlates include inflammation, symptoms of depression, sleep disorders and obesity. Fatigue in KTR leads to significant functional impairment, it is common among KTR poorly adherent to immunosuppressive therapy and is associated with a serious deterioration of quality of life. The following databases were searched for relevant studies up to November 2020: Medline, PubMed, Web of Science and the Cochrane Library. Several studies have compared the prevalence and severity of fatigue between KTR and hemodialysis or healthy patients. They have shown that fatigue determines a significant functional deterioration with less chance of having a paid job and a significant change in quality of life. The aim of the review is to report methods to assess fatigue and its prevalence in KTR patients, compared to HD subjects and define the effects of fatigue on health status and daily life. There is no evidence of studies on the treatment of this symptom in KTR. Efforts to identify and treat fatigue should be a priority to improve the quality of life of KTR.

Cystic fibrosis is characterized by lung dysfunction involving mucus hypersecretion, bacterial infections, and inflammatory response. Inflammation triggers pro-fibrotic signals that compromise lung structure and function. At present, several in vitro cystic fibrosis models have been developed to study epithelial dysfunction but none of these focuses on stromal alterations. Here we show a new cystic fibrosis 3D stromal lung model made up of primary fibroblasts embedded in their own extracellular matrix and investigate its morphological and transcriptomic features. Cystic fibrosis fibroblasts showed a high proliferation rate and produced an abundant and chaotic matrix with increased protein content and elastic modulus. More interesting, they had enhanced pro-fibrotic markers and genes involved in epithelial function and inflammatory response. In conclusion, our study reveals that cystic fibrosis fibroblasts maintain in vitro an activated pro-fibrotic state. This abnormality may play in vivo a role in the modulation of epithelial and inflammatory cell behavior and lung remodeling. We argue that the proposed bioengineered model may provide new insights on epithelial/stromal/inflammatory cells crosstalk in cystic fibrosis, paving the way for novel therapeutic strategies.

Mathmatical Hydrologic models simulate real world environmental processes through different strategies. Each process is calculated by means of methods that utilize physical parameters for representing the real world system. some parameters are obtained from tables, some of them are optimized and others may be calculated using environmental variables. Although the domain software provides a wide range of models, there is not a conceptual architecture that allows the maintenance of the vast knowledge about simulation strategies and parameters collected in environmental management organizations, facilitating the flexible simulation scenarios configuration. The present work shows how to face this problem by means of conceptual analysis models organized in the scope of a general architecture. It's also possible for the given architecture, to analyze and define microarchitectures for software components releated to particular problems. In the present work, conceptual microarchitectures are definesd to construct a knowlegde level for hydrologic models systems starting from a general conceptual Environmental Information Systems architecture. To get the required flexibility for the conceptual and design models, high-level components are identified and different kinds of patterns are applied.

The effect of forests on flow and flood lamination decreases as the magnitude and intensity of torrential events and the watershed surface increase, thus resulting negligible when extreme events affect large catchments. However the effect of forests is advantageous in case of major events, which occur more often, and is particularly effective in soil erosion control. As a result, forests have been extensively used for watershed management and restoration, since they regulate water and sediments cycles, preventing the degradation of catchments.

Unconverted lignin is available as residual sludge with water content in the range of 40-60% by mass from 2nd generation bio-ethanol production process. Fluidized bed combustion was studied as a possible method to valorize such a biomass material, upon mixing and homogenizing with rapeseed oil for producing a fuel slurry. Combustion tests were carried out at steady state in a pilot unit with submerged feeding of the fuel slurry. The operation with the slurry resulted reliable, after the adoption of measures for improving the slurry homogeneity and flowability. To this aim, particular care was dedicated to the production and characterization of the slurry, whose rheological properties are typical of a non-Newtonian (pseudo-plastic) fluid. The combustion tests proved that C content in the ash samples at the cyclone was very low and the combustion efficiency was higher than 99.5%. A temperature increase was registered in the freeboard with respect to the bed as consequence of volatile matter combustion, typical of biomass fuels. The normalized NO emission was compliant with the Italian regulation for biogenic fuels. The bed material was enriched in K and Na from the ashes, although no bed agglomeration phenomena occurred.

Water Resources Information Systems (WRIS) present different types of problems during the data storage and analysis phases, related with the complex nature of the environmental data spacio-temporal phenomena. There are many questions to deal with, such as geographic representation of environmental variables, large time- series management,measurements and observations related with different hydrologic phenomena recording and the integration of simulations models to information systems. Conceptual models allow us to understand and simplify problems in a specific domain. These problems can be expressed through analysis patterns, which reflect conceptual structures of an application domain speeding up the development of the abstract analysis model. This model will be able to capture the main requirements from real world problems. This type of patterns, are used in the present paper to define conceptual microarchitectures that allow the appropriate representation of environmental information in WRIS. Accordingly, the physic domain environmental objects are initially identified and an architecture style is defined, allowing this way the integration of WRIS with another interacting systems. The representation of the hydrological phenomena spatial component, is made by means of the conceptual Framework GeoFrame specialization.

The present paper reports on experiments of fluidized bed combustion of dry and wet olive husks. The olive husks are a biogenic residue of the olive oil industry, accounting for around 80 % of olive mass on wet basis. They have residual water content up to 70 % and rather high heating value (i.e. 22.3 MJ/kg on dry basis). Huge production of olive husks occurs seasonally in the Mediterranean area, posing problems for proper disposal and valorisation because of the difficulty to store this material for long times. The research demonstrated that the olive husks can be smoothly and effectively burnt in fluidized bed with high combustion efficiency and very low emissions of pollutants and solid particulate in a bed temperature range between 800 and 850 °C. The energy balance on the combustor shows that a fraction of 10-15 % of the heat input can be directly extracted from the fluidized bed, the remaining being available in the hot flue gases. The focus was also on the emissions of nitrogen oxide. The research can have practical application for small scale and local installation, e.g. at olive oil factory, as demonstrated by the experimental campaign at pilot scale.

Abstract Background Molecular characterization of collagen-VI related myopathies currently relies on standard sequencing, which yields a detection rate approximating 75-79% in Ullrich congenital muscular dystrophy (UCMD) and 60-65% in Bethlem myopathy (BM) patients as PCR-based techniques tend to miss gross genomic rearrangements as well as copy number variations (CNVs) in both the coding sequence and intronic regions. Methods We have designed a custom oligonucleotide CGH array in order to investigate the presence of CNVs in the coding and non-coding regions of COL6A1, A2, A3, A5 and A6 genes and a group of genes functionally related to collagen VI. A cohort of 12 patients with UCMD/BM negative at sequencing analysis and 2 subjects carrying a single COL6 mutation whose clinical phenotype was not explicable by inheritance were selected and the occurrence of allelic and genetic heterogeneity explored. Results A deletion within intron 1A of the COL6A2 gene, occurring in compound heterozygosity with a small deletion in exon 28, previously detected by routine sequencing, was identified in a BM patient. RNA studies showed monoallelic transcription of the COL6A2 gene, thus elucidating the functional effect of the intronic deletion. No pathogenic mutations were identified in the remaining analyzed patients, either within COL6A genes, or in genes functionally related to collagen VI. Conclusions Our custom CGH array may represent a useful complementary diagnostic tool, especially in recessive forms of the disease, when only one mutant allele is detected by standard sequencing. The intronic deletion we identified represents the first example of a pure intronic mutation in COL6A genes.