The aspect of safety in electronic devices has turned out to be a huge challenge for the world of science. Thus far, satisfactory power and energy densities, efficiency, and cell capacities have been ...achieved. Unfortunately, the explosiveness and thermal runaway of the cells prevents them from being used in demanding applications such as electric cars at higher temperatures. The main aim of this review is to highlight different electrolytes used in lithium-ion cells as well as the flammability aspect. In the paper, the authors present liquid inorganic electrolytes, composite polymer-ceramic electrolytes, ionic liquids (IL), polymeric ionic liquids, polymer electrolytes (solvent-free polymer electrolytes (SPEs), gel polymer electrolytes (GPEs), and composite polymer electrolytes (CPEs)), and different flame retardants used to prevent the thermal runaway and combustion of lithium-ion batteries (LIBs). Additionally, various flame tests used for electrolytes in LIBs have been adopted. Aside from a detailed description of the electrolytes consumed in LIBs. Last section in this work discusses hydrogen as a source of fuel cell operation and its practical application as a global trend that supports green chemistry.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This manuscript shows the use of natural polysaccharides such as starch and cellulose as a carbon source for fuel cells. To achieve this, two innovative methods of obtaining hydrogen have been shown: ...by adsorption and by enzyme. The carbonization path of the material results in excellent sorption properties and allows gas with high efficiency to be obtained. The enzymatic method for the degradation of the compound is more expensive because specific enzymes (such as laccase, tyrosinase) must be used, but it allows greater control of the properties of the obtained material. A scientific novelty is the use of natural raw materials, the use of which increases the biodegradability of the electrochemical system and also reduces the cost of raw materials and increases the range of their acquisition. Energy should be generated where it is used. Another goal is decentralization, and thanks to the proposed solutions, hydrogen cells represent an innovative alternative to today’s energy giants—also for independent power supply to households. The proposed harvesting paths are intended to drive rail vehicles in order to reduce emissions and secondary pollution of the environment. The goals of both methods were easy recycling, high efficiency, increased environmental friendliness, low cost and a short hydrogen production path.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The understanding of the molecular biology of pediatric neuronal and mixed neuronal-glial brain tumors is still insufficient due to low frequency and heterogeneity of those lesions which comprise ...several subtypes presenting neuronal and/or neuronal-glial differentiation. Important is that the most frequent ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) showed limited number of detectable molecular alterations. In such cases analyses of additional genomic mechanisms seem to be the most promising. The aim of the study was to evaluate microRNA (miRNA) profiles in GGs, DNETs and pilocytic asytrocytomas (PA) and test the hypothesis of plausible miRNA connection with histopathological subtypes of particular pediatric glial and mixed glioneronal tumors.
The study was designed as the two-stage analysis. Microarray testing was performed with the use of the miRCURY LNA microRNA Array technology in 51 cases. Validation set comprised 107 samples used during confirmation of the profiling results by qPCR bioinformatic analysis.
Microarray data was compared between the groups using an analysis of variance with the Benjamini-Hochberg procedure used to estimate false discovery rates. After filtration 782 miRNAs were eligible for further analysis. Based on the results of 10 × 10-fold cross-validation J48 algorithm was identified as the most resilient to overfitting. Pairwise comparison showed the DNETs to be the most divergent with the largest number of miRNAs differing from either of the two comparative groups. Validation of array analysis was performed for miRNAs used in the classification model: miR-155-5p, miR-4754, miR-4530, miR-628-3p, let-7b-3p, miR-4758-3p, miRPlus-A1086 and miR-891a-5p. Model developed on their expression measured by qPCR showed weighted AUC of 0.97 (95% CI for all classes ranging from 0.91 to 1.00). A computational analysis was used to identify mRNA targets for final set of selected miRNAs using miRWalk database. Among genomic targets of selected molecules ZBTB20, LCOR, PFKFB2, SYNJ2BP and TPD52 genes were noted.
Our data showed the existence of miRNAs which expression is specific for different histological types of tumors. miRNA expression analysis may be useful in in-depth molecular diagnostic process of the tumors and could elucidate their origins and molecular background.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The paper presents the investigations of exhaust emissions under actual operation of two rail vehicles: a track geometry vehicle and a clearance vehicle. The environmental assessment of this type of ...objects is difficult due to the necessity of adapting the measurement equipment and meeting the safety requirements during the tests (particularly regarding the distance from the overhead electrical lines). The authors have proposed and developed a unique research methodology, based on which a detailed exhaust emissions analysis (CO, HC, NOx, and PM) was carried out. The complex assessment included the unit and on-track exhaust emissions. In the analyses, the authors also included the operating conditions of the powertrains of the tested machinery. The obtained environmental indexes were referred to the homologation standards, according to which the vehicles were approved for operation. Due to the nature of operation of the tested vehicles, the authors carried out a comprehensive environmental assessment in the daily and annual approach as well as in the aspect of their operation as combined vehicles, which is a novel approach to the assessment of the environmental performance of this type of objects.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract Background Subependymal giant cell astrocytoma is a brain tumor associated with tuberous sclerosis complex. There are two treatment options for subependymal giant cell astrocytomas: surgery ...or mammalian target of rapamycin inhibitor. The analysis of outcome of subependymal giant cell astrocytoma surgery may help characterize the patients who may benefit from pharmacotherapy. Methods Sixty-four subependymal giant cell astrocytoma surgeries in 57 tuberous sclerosis complex patients with at least a 12-month follow-up were included in the study. The tumor size, age of the patients, mutation in the TSC1 or TSC2 gene, indication for the surgery, and postsurgical complications were analyzed. Results The mean age of patients at surgery was 9.7 years. Mean follow-up after surgery was 63.7 months. Thirty-seven (57.8%) tumors were symptomatic and 27 (42.2%) were asymptomatic. Patients with TSC2 mutations developed subependymal giant cell astrocytoma at a significantly younger age than individuals with TSC1 mutations. Four patients (6.2% of all surgeries) died after surgery. Surgery-related complications were reported in 0%, 46%, 83%, 81%, and 67% of patients with tumors <2 cm, between 2 and 3 cm, between 3 and 4 cm, >4 cm, and bilateral subependymal giant cell astrocytomas, respectively, and were most common in children younger than 3 years of age. The most common complications included hemiparesis, hydrocephalus, hematoma, and cognitive decline. Conclusions Our study indicates that subependymal giant cell astrocytoma surgery is associated with significant risk in individuals with bilateral subependymal giant cell astrocytomas, tumors bigger than 2 cm, and in children younger than 3 years of age. Therefore, tuberous sclerosis complex patients should be thoroughly screened for subependymal giant cell astrocytoma growth, and early treatment should be considered in selected patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Neuronal-glial tumors (ganglioglioma and dysembryoplastic neuroepithelial tumor) are a frequent cause of focal, drug-resistant and epilepsy in children and young adults, that is amenable for surgical ...treatment.
Assessment of late outcome of surgical treatment and degree of seizure control, as well as prognostic significance of selected clinical factors.
52 Pediatric patients presenting with epilepsy, lesion of mesio-basal temporal lobe and histologically verified neuronal-glial tumor treated at our facility since 2000–2011.
After the mean follow-up of 2.94 years, satisfactory treatment outcome (Engel classes I and II) was obtained in 92% of the patients (n=48). Poor outcome (Engel class III) was seen in 8% of patients (n=4). New neurological deficits appeared in 28% of the patients (n=20) but in most of them resolved over time.
In patients with drug-resistant epilepsy and a lesion of mesial-basal part of temporal lobe suggestive of a glial-neuronal tumor, surgical treatment is strongly recommended, aiming at excision of tumor and elimination of seizures. Histological verification of the lesion is a pre-requisite for optimal treatment planning. In most patients, both treatment goals may be reached. Short duration of epilepsy prior to surgery and young age are favorable prognostic factors. Histological diagnosis of GG, co-existence of cortical dysplasia and location of tumor extending beyond mesial-basal temporal structures are associated with a higher risk of postoperative complications. These may out-weight expected benefits of surgery.
Summary Focal cortical dysplasia (FCD) is a developmental brain disorder characterized by localized abnormalities of cortical layering and neuronal morphology. It is associated with pharmacologically ...intractable forms of epilepsy in both children and adults. The mechanisms that underlie FCD-associated seizures and lead to the progression of the disease are unclear. Matrix metalloproteinases (MMPs) are enzymes that are able to influence neuronal function through extracellular proteolysis in various normal and pathological conditions. The results of experiments that have used rodent models showed that extracellular MMP-9 can play an important role in epileptogenesis. However, no studies have shown that MMP-9 is involved in the pathogenesis of human epilepsy. The aim of the present study was to determine whether MMP-9 plays a role in intractable epilepsy. Using an unbiased antibody microarray approach, we found that up regulation of MMP-9 is prominent and consistent in FCD tissue derived from epilepsy surgery, regardless of the patient's age. Additionally, an up regulation of MMP-1, -2, -8, -10, and -13 was found but was either less pronounced or limited only to adult cases. In the dysplastic cortex, immunohistochemistry revealed that the highest MMP-9 immuno reactivity occurred in the cytoplasm of abnormal neurons and balloon cells. The neuronal over expression of MMP-9 also occurred in sclerotic hippocampi that were excised together with the dysplastic cortex, but sclerotic hippocampi were free of dysplastic features. In both locations, MMP-9 was also found in reactive astrocytes, albeit to a lesser extent. At the subcellular level, increased MMP-9 immunoreactivity was prominently upregulated at synapses. Thus, although upregulation of the enzyme in FCD is not causally linked to the developmental malformation, it may be a result of ongoing abnormal synaptic plasticity. The present findings support the hypothesis of the pathogenic role of MMP-9 in human epilepsy and may stimulate discussions about whether MMPs could be novel therapeutic targets for intractable epilepsy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Introduction: Every evidence-based scientific work requires precise and reliable data. In clinical medicine, this means searching for patients fulfilling specific criteria. Unfortunately, most ...hospital-operated information systems are designed to process data concerning treatment of specific patients, mainly in its medical and administrative aspects, while a crosssectional search for patients with a specific pathology at a specific location is difficult if not impossible. Therefore, most of these databases are essentially useless for scientific purposes. Material and method: Based on medical records of all patients treated at our facility, we have created a simple database enabling a quick search for patients fulfilling specific criteria. We used Microsoft® Office Access® software installed on a standard PC. Structure and the use of database are described in detail. Results: Our database contains basic information about 16,126 patients treated over 38 years and occupies 5.19 MB. To date, 48 queries have been performed, providing reliable scientific material. Conclusion: This is an effective and comprehensive tool for the search of patients or items fulfilling specific criteria. To the best of our knowledge, such a tool for the management of clinical data has not been described to-date. After introducing appropriate modifications, a similar database will be very useful in every clinical centre.
The article concerns the research on the emission of pollutants of a rail-road tractor in two stationary research tests. The purpose of the tests was to carry out control tests of pollutant emissions ...and their analysis. The object used during the works was approved in accordance with the Stage V standard, which requires measurements of emissivity both in stationary, dynamic and real conditions. Despite the requirement to test engines installed on a vehicle during their normal duty cycle with PEMS, the emission limits measured in this test have not yet been defined. Therefore, the work below focuses on the stationary test cycle. The measurements were carried out in accordance with the combustion engine operating points described in the approval test, and then compared with the modernized NRSC test. It contains modified measuring points and rotational speeds of the crankshaft, adopted on the basis of the most common operating parameters of agricultural tractor combustion engines in real operating conditions. The measurements were performed with the use of a mobile dynamometer and devices for measuring emissions of harmful exhaust gas compounds and recording on-board data. In the test, the vehicle drive system worked at fixed operating points, with defined values of crankshaft rotational speed and load. Based on the recorded data on the concentrations of pollutants in the exhaust gases, the specific emission of the object was determined. In the final stage of the work, these data were used to perform a comparative analysis with the emission limits contained in the standard.
Track works typically require the use of special-purpose rail machines, in which the main source of propulsion are high-power compression ignition engines. Reliance on these types of engines, which ...are characterized by a significant degree of wear and tear, relates to a relatively high specific fuel consumption and the exhaust emissions of toxic compounds. Using such rail machines to perform modernization and repair works has a negative impact on the natural environment. The article presents test results of toxic compounds exhaust emissions as measured from a special purpose rail machine. The tested vehicle was a machine designed for profiling the ballast cess labelled as PŁT-500. The machine was classified as NRMM (Non Road Mobile Machinery) and used for profiling and cleaning the cess. A PEMS (Portable Emissions Measurement System) type apparatus was used for the emissions measurement. This made it possible to measure the exhaust emissions as RDE (Real Driving Emissions) of toxic compounds from the machine in real operating conditions. The obtained test results include the measured exhaust emissions of gaseous compounds: CO, CO2, HC and NOx as well as the vehicle fuel consumption while performing its track works.
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