27 research outputs found
Effects of wasted anesthetic gases on human lymphocytes – A genetic study
AbstractInformation on potential genetic damage in humans after exposure to waste anaesthetic gases in Egyptian hospitals is scarce. To evaluate the possible genotoxic effects of waste anaesthetic gases, the chromosomal aberrations [CA] and the sister chromatid exchange [SCE] tests, were studied in peripheral blood lymphocytes in 26 operating room personnel (exposed group) currently employed at Tanta University hospitals, in comparison to a group of 13 non-exposed persons (control group), matched by age, sex and smoking habits. The results showed a statistically significant increase in chromosomal aberrations and sister chromatid exchange in the exposed persons in comparison to controls. Also it suggests that exposure to waste anaesthetic gases has the potential to cause changes in human genome
A numerical method to solve higher-order fractional differential equations
In this paper, we present a new numerical method to solve fractional differential equations.
Given a fractional derivative of arbitrary real order, we present an approximation formula for
the fractional operator that involves integer-order derivatives only. With this, we can rewrite
FDEs in terms of a classical one and then apply any known technique. With some examples,
we show the accuracy of the method
Overview of recent TJ-II stellarator results
The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented. ISSN:0029-5515 ISSN:1741-432
Parâmetros hematológicos e bioquímicos da tilápia-do-Nilo (Oreochromis niloticus L.) sob estresse por exposição ao ar
No presente trabalho avaliaram-se os parâmetros hematológicos e bioquímicos de exemplares adultos de tilápias (Oreochromis niloticus) sob a influência do fator estresse fisiológico em animais submetidos à exposição ao ar durante a engorda em sistema raceway. Foram analisados o eritrograma, teor de hemoglobina, volume globular, o volume corpuscular médio (VCM), a hemoglobina corpuscular média (HCM), a concentração de hemoglobina corpuscular média (CHCM), o leucograma, contagem diferencial de leucócitos, o plaquetograma, a glicose, a proteína total, o colesterol, o triglicerídeo e os eletrólitos (cálcio, cloretos, sódio e potássio). Os resultados revelaram que houve uma homogeneidade de distribuição para hemácias, volume globular, hemoglobina, índices hemantimétricos, proteína total, glicose, colesterol, e íons séricos, indicados pelos valores relativamente baixos do coeficiente de variação. Houve correlação positiva somente para leucócitos totais, células de defesa orgânica (neutrófilos e linfócitos), glicose, colesterol, sódio e cálcio. Quanto ao leucograma, à medida que os animais foram expostos ao ar, o número de leucócitos diminuiu gradativamente (leucopenia), ocorrendo simultaneamente neutrofilia e linfopenia. O índice glicêmico constituiu um bom indicador de estresse fisiológico, devido à hiperglicemia (82,0±20,88mg/dL) demonstrada nos tratamentos. A exposição ao ar constituiu um fator de desequilíbrio na homeostase iônica, e na síntese de colesterol endógeno. Entretanto, o tempo de recuperação não ocasionou a completa reabilitação fisiológica frente ao desafio imposto
Natural gas dehydration by desiccant materials
Water vapor in a natural gas stream can result in line plugging due to hydrate formation, reduction of line capacity due to collection of free water in the line, and increased risk of damage to the pipeline due to the corrosive effects of water. Therefore, water vapor must be removed from natural gas to prevent hydrate formation and corrosion from condensed water.
Gas dehydration is the process of removing water vapor from a gas stream to lower the temperature at which water will condense from the stream; this temperature is called the “dew point” of the gas. Molecular sieves are considered as one of the most important materials that are used as desiccant materials in industrial natural gas dehydration.
This work shows a study of natural gas dehydration using 3A molecular sieve as a type of solid desiccant materials, the scope of this work was to build up a pilot scale unit for a natural gas dehydration as simulation of actual existing plant for Egyptian Western Desert Gas Company (WDGC). The effect of different operating conditions (water vapor concentration and gas flow rate) on dehydration of natural gas was studied.
The experimental setup consists of cylinder filled with 3A molecular sieve to form a fixed bed, then pass through this bed natural gas with different water vapor concentration, The experimental setup is fitted with facilities to control bed pressure, flow rate, measure water vapor concentration and bed temperature, a gas heater was used to activate molecular sieve bed.
Increasing water vapor concentration in inlet feed gas leads to a marked decrease in dehydration efficiency. As expected, a higher inlet flow rate of natural gas decrease dehydration efficiency. Increasing feed pressure leads to higher dehydration efficiency
Overview of the 2022 WHO Classification of Neuroendocrine Neoplasms
In this review, we detail the changes and the relevant features that are applied to neuroendocrine neoplasms (NENs) in the 2022 WHO Classification of Endocrine and Neuroendocrine Tumors. Using a question-and-answer approach, we discuss the consolidation of the nomenclature that distinguishes neuronal paragangliomas from epithelial neoplasms, which are divided into well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs). The criteria for these distinctions based on differentiation are outlined. NETs are generally (but not always) graded as G1, G2, and G3 based on proliferation, whereas NECs are by definition high grade; the importance of Ki67 as a tool for classification and grading is emphasized. The clinical relevance of proper classification is explained, and the importance of hormonal function is examined, including eutopic and ectopic hormone production. The tools available to pathologists for accurate classification include the conventional biomarkers of neuroendocrine lineage and differentiation, INSM1, synaptophysin, chromogranins, and somatostatin receptors (SSTRs), but also include transcription factors that can identify the site of origin of a metastatic lesion of unknown primary site, as well as hormones, enzymes, and keratins that play a role in functional and structural correlation. The recognition of highly proliferative, well-differentiated NETs has resulted in the need for biomarkers that can distinguish these G3 NETs from NECs, including stains to determine expression of SSTRs and those that can indicate the unique molecular pathogenetic alterations that underlie the distinction, for example, global loss of RB and aberrant p53 in pancreatic NECs compared with loss of ATRX, DAXX, and menin in pancreatic NETs. Other differential diagnoses are discussed with recommendations for biomarkers that can assist in correct classification, including the distinctions between epithelial and non-epithelial NENs that have allowed reclassification of epithelial NETs in the spine, in the duodenum, and in the middle ear; the first two may be composite tumors with neuronal and glial elements, and as this feature is integral to the duodenal lesion, it is now classified as composite gangliocytoma/neuroma and neuroendocrine tumor (CoGNET). The many other aspects of differential diagnosis are detailed with recommendations for biomarkers that can distinguish NENs from non-neuroendocrine lesions that can mimic their morphology. The concepts of mixed neuroendocrine and non-neuroendocrine (MiNEN) and amphicrine tumors are clarified with information about how to approach such lesions in routine practice. Theranostic biomarkers that assist patient management are reviewed. Given the significant proportion of NENs that are associated with germline mutations that predispose to this disease, we explain the role of the pathologist in identifying precursor lesions and applying molecular immunohistochemistry to guide genetic testing