2,131 research outputs found
Measuring Injectors Fouling in Internal Combustion Engines through Imaging
Abstract The use of liquid fuels derived from biomass in internal combustion engines, based on direct fuel injection, involves the formation of a large amount of carbon deposits on the tip of injectors which significantly influence emissions and engine performance. Currently most of the research activities are focused on the physical and chemical evaluation of deposits, using GC/MS (gas chromatography/mass spectrometry) analysis of alcoholic solutions with dissolved samples and FESEM (Field Emission Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) analysis to characterize their microstructures. There are few methodologies to quantify the temporal fouling on the injectors in order to define a correlation between fouling, fuel and engine performance. The development of a methodology to compare the different effects of fouling obtained diversifying the fuel input of a direct injection engine is the aim of this work. The methodology is based on photography and post-processing of images to obtain a pixel count linked to a fouling index. The effect of lighting and visual angle is taken into account and a preliminary qualitative evaluation of the performance of the methodology is carried out. This methodology was also carried out to determine the minimum number of photos required to quantify the deposit independently by the orientation
Integrating chemical, biological and soil fauna variables during beech leaf litter decay: A partial least squares approach for a comprehensive view of the decomposition process
Litter decomposition is an ecosystem process that is regulated by a multitude of factors and by their complex interactions. Current decomposition paradigms do not always offer a coherent view of the process because it can be hardly understood without a thorough analysis of interacting factors. Thus, there is a need to further understand the mechanics of litter decay with a comprehensive approach, especially in temperate forest ecosystems where decomposition plays a crucial role in regulating them as source or sink of CO2. Therefore, the aim of this work was to identify the interactions between chemical, biological and soil fauna variables in order to discern driving variables and the changes in their interactions during long-time (1300 days) beech leaf litter decomposition. In order to investigate patterns of variation and co-variation within and between datasets, we used Two-block Partial Least Squares, helping us to interpret the decomposition process with a systemic approach. Our key findings showed that the decomposition process of beech litter in two Mediterranean forests was driven by litter quality at the beginning and in the later stages of decomposition, while edaphic and climatic factors were implied in the central steps, with a dramatic change of scenario around 2.5 years. Simultaneous and interacting changes in chemical variables, extracellular enzyme activities, and soil fauna were shown, with a significant role of lignocellulosic components and enzymes involved in their degradation, Mn residual weight, and abundance of Collembola
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Ca2+-activated K+ channels modulate microglia affecting motor neuron survivalin hSOD1G93A mice
Recent studies described a critical role for microglia in amyotrophic lateral sclerosis (ALS), where these CNS-resident immune cells participate in the establishment of an inflammatory microenvironment that contributes to motor neuron degeneration. Understanding the mechanisms leading to microglia activation in ALS could help to identify specific molecular pathways which could be targeted to reduce or delay motor neuron degeneration and muscle paralysis in patients. The intermediate-conductance calcium-activated potassium channel KCa3.1 has been reported to modulate the "pro-inflammatory" phenotype of microglia in different pathological conditions. We here investigated the effects of blocking KCa3.1 activity in the hSOD1G93AALS mouse model, which recapitulates many features of the human disease. We report that treatment of hSOD1G93A mice with a selective KCa3.1 inhibitor, 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34), attenuates the "pro-inflammatory" phenotype of microglia in the spinal cord, reduces motor neuron death, delays onset of muscle weakness, and increases survival. Specifically, inhibition of KCa3.1 channels slowed muscle denervation, decreased the expression of the fetal acetylcholine receptor γ subunit and reduced neuromuscular junction damage. Taken together, these results demonstrate a key role for KCa3.1 in driving a pro-inflammatory microglia phenotype in ALS
Assicurazioni e sviluppo: lezioni dalla storia
Il volume raccoglie contributi e testimonianze di studiosi sul tema del rapporto tra le vicende del settore assicurativo e lo sviluppo economico e sociale del Paese. Pubblicato in occasione della ricorrenza dei 150 anni dell’Unità d’Italia, documenta non solo il rilevante ruolo sociale svolto da questa importante componente dell’industria finanziaria nel sostenere in vario modo lo sviluppo, e il modello di sviluppo nelle diverse fasi storiche della storia post-unitaria. Testimonia anche come l’andamento del settore si sia adattato e abbia concorso a caratterizzare i rapporti tra pubblico e privato nella struttura economico-industriale, la domanda di protezione e di copertura dei rischi proveniente dalle imprese e dalle famiglie, l’articolazione e il funzionamento dei servizi, delle garanzie pubbliche e delle forme di protezione offerte dallo Stato sociale, lo stato delle tecnologie, della ricerca economica e statistica e dell’efficienza della pubblica amministrazione. L’obiettivo è quello di capire e proiettare sul futuro il ruolo del settore assicurativo di fronte ai grandi cambiamenti in corso e agli scenari di rischio in evoluzione. Tra gli interventi inclusi nel volume quelli di Giuliano Amato, Pierluigi Ciocca, Elsa Fornero, Robin Pearson e Gianni Toniolo)
Internalizing symptoms in children affected by childhood absence epilepsy: A preliminary study
Introduction: Childhood absence epilepsy (CAE) is a common type of pediatric idiopathic generalized epilepsy, characterized by multiple seizures of typical absence, with typical EEG pattern consisting in bilateral synchronous and symmetrical discharges of generalized 3 Hz spike-wave (SWDs). Recently, some researchers have suggested that the underlying epileptogenic mechanism of absence seizures selectively involves the frontal cortical circuits, also supported by video-electroencephalography data(3). These data may be considered as a new window in CAE comprehension and management, particularly about symptoms different from seizure that children affected may present. In this light, aim of the present study is evaluating the presence of internalizing problems in prepubertal children affected by CAE. Material and methods: 18 patients (10 females, 8 males) ranging age from 8-11 years (mean age 9.36 ± 1.32) affected by typical CAE were recruited. Control group was composed by 43 subjects (32 females, 11 males) (mean age 8.54 ± 2.01). All subjects were screened for internalizing symptoms with SAFA-A scale and CDI test. Results: The two groups were comparable for age (p=0.117) and sex distribution (p=0.251). CAE children showed significantly higher score than controls for anxiety (p<0.001) and depressive symptoms screening tests (p<0.001) (Table 1). Conclusions: Results of present study suggest the importance of screening for anxiety and depressive signs in CAE children, in order to optimize their management beyond the exclusive idea to control and stop epileptic seizure only
Transplantation and young surgeons in italy
The relation between young surgeons and transplantation has always been a "love and hate" one. Until a few years ago this branch of surgery was seen as pioneering, with extreme and and extensive training, and was reserved to few elected members. Nowadays things are different. In this article we try to understand the true reasons that young Italian surgeons avoid transplantation surgery
An integrated metabolomics approach for the research of new cerebrospinal fluid biomarkers of multiple sclerosis
(1) Lipid profiling in MuS and OND patients. (2) Search of alterations associated with MuS. (3) Characterization of differences
Growing bone tissue-engineered niches with graded osteogenicity: an in vitro method for biomimetic construct assembly
The traditional bone tissue-engineering approach exploits mesenchymal stem cells ( MSCs) to be seeded once only on three-dimensional (3D) scaffolds, hence, differentiated for a certain period of time and resulting in a homogeneous osteoblast population at the endpoint. However, after achieving terminal osteodifferentiation, cell viability is usually markedly compromised. On the other hand, naturally occurring osteogenesis results from the coexistence of MSC progenies at distinct differentiative stages in the same microenvironment. This diversification also enables long-term viability of the mature tissue. We report an easy and tunable in vitro method to engineer simple osteogenic cell niches in a biomimetic fashion. The niches were grown via periodic reseeding of undifferentiated MSCs on MSC/scaffold constructs, the latter undergoing osteogenic commitment. Timefractioning of the seeded cell number during differentiation time of the constructs allowed graded osteogenic cell populations to be grown together on the same scaffolds (i.e., not only terminally differentiated osteoblasts). In such cell-dynamic systems, the overall differentiative stage of the constructs could also be tuned by varying the cell density seeded at each inoculation. In this way, we generated two different biomimetic niche models able to host good reservoirs of preosteoblasts and other osteoprogenitors after 21 culture days. At that time, the niche type resulting in 40.8% of immature osteogenic progenies and only 59.2% of mature osteoblasts showed a calcium content comparable to the constructs obtained with the traditional culture method (i.e., 100.03 – 29.30 vs. 78.51 – 28.50 pg/cell, respectively; p = not significant), the latter colonized only by fully differentiated osteoblasts showing exhausted viability. This assembly method for tissue-engineered constructs enabled a set of important parameters, such as viability, colonization, and osteogenic yield of the MSCs to be balanced on 3D scaffolds, thus achieving biomimetic in vitro models with graded osteogenicity, which are more complex and reliable than those currently used by tissue engineers
Primary hyperoxaluria in Italy: the past 30 years and the near future of a (not so) rare disease
R0 surgical resection of giant dedifferentiated retroperitoneal liposarcomas in the COVID era with and without nephrectomy: A case report
: Retroperitoneal sarcomas (RPSs) are rare findings that can grow into large masses without eliciting severe symptoms. At present, surgical resection is the only radical therapy, whenever it can be performed with the aim to achieve a complete removal of the tumor. The present report describes two consecutive cases of RPSs that resulted in dedifferentiated liposarcomas (DDLPSs) and these patients underwent R0 surgical resection with and without a nephron-sparing procedure. The diagnostic workup, the surgical approach, the impact of late surgical management due to the COVID pandemic and the latest literature on the topic are discussed and analyzed. The patients, who refused to undergo any medical examination during the prior 2 years due to the COVID pandemic, were admitted to Federico II University Hospital (Naples, Italy) complaining about weight loss and general abdominal discomfort. In the first case, a primitive giant abdominal right neoplasm of retroperitoneal origin enveloping and medializing the right kidney was observed. The second patient had a similar primitive retroperitoneal giant left neoplasm, which did not affect the kidney. Given the characteristics of the masses and the absence of distant metastases, after a multidisciplinary discussion, radical surgical removal was carried out for both patients. The lesions appeared well-defined from the surrounding tissues, and markedly compressed all the adjacent organs, without signs of infiltration. In the first patient, the right kidney was surrounded and undetachable from the tumor and it was removed en bloc with the mass. The second patient benefited from a nephron-sparing resection, due to the existence of a clear cleavage plane. The postoperative courses were uneventful. Both the histological examinations were oriented towards a DDLPS and both patients benefited from adjuvant chemotherapy. In conclusion, the treatment of giant RPS is still challenging and requires multidisciplinary treatment as well as, when possible, radical surgical removal. The lack of tissue infiltration and the avoidance of excision or reconstruction of major organs (including the kidney) could lead to an easier postoperative course and an improved prognosis. When possible, surgical management of recurrences or incompletely resected masses must be pursued. Since the COVID pandemic caused limited medicalization of a number of population groups and delayed diagnosis of other oncologic diseases, an increased number of DDLPSs could be expected in the near future
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