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Time is an extremely important element in the field of GNSS positioning. In precise positioning with a single-centimetre accuracy, satellite clock corrections are used. In this article, the longest available data set of satellite clock corrections of four GNSS systems from 2014 to 2021 was analysed. This study covers the determination of the quality (outliers number and magnitude), availability, stability, and determination of the specificity and nature of the clock correction for each satellite system. One problem with the two newest satellite systems (Galileo and BeiDou) is the lack of availability of satellite signals in the early years of the analysis. These data were available only in the later years of the period covered by the analysis, as most of the satellites have only been in orbit since 2018-2019. Interestingly, the percentage of outlying observations was highest in Galileo and lowest in BeiDou. Phase and frequency plots showed a significant number of outlying observations. On the other hand, after eliminating outlying observations, each system showed a characteristic graph waveform. The most consistent and stable satellite clock corrections are provided by the GPS and GLONASS systems. The main problems discussed in this paper are the determination of the number and magnitude of outliers in clock products of four GNSS systems (GPS, GLONASS, Galileo, Beidou) and the study on the long-term stability of GNSS clocks analysis, which covers the years 2014-2021.
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OBJECTIVES: As part of this study, a comparative analysis of the temporal and masseter muscle electrical activity at rest and during mandible excursion positions (protrusion, laterotrusion and maximal occlusion) was performed among patients aged 21 to 68 years. METHODS: Each of three groups: opioid addicts, alcohol addicts and the control group - consisted of 30 individuals (90 individuals in total, including 37 females and 53 males). Electrodes were placed on the masseter venters and mandibular movements were executed: right/left lateral, protrusion, intercuspation, rest and MVC. Then the same routine was applied to the anterior parts of temporal muscles. RESULTS: Based on EMG data in alcohol addicts, higher electrical activity of masseters and temporal muscles was observed during the mandible excursions, compared to the control group. In comparison of opiate addicts to healthy controls, no statistical significance was observed in electrical activity of masseter and temporal muscles. CONCLUSIONS: On the basis of the conducted research, a conclusion can be drawn that alcohol addiction significantly affects the function of the largest muscles of the stomatognathic system.
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Músculo Masetero , Músculo Temporal , Atención Odontológica , Electromiografía , Femenino , Humanos , Masculino , MandíbulaRESUMEN
The issue addressed in this publication concerns new Air Traffic Management (ATM) functionality, identified in the Commission Implementing Regulation (EU) No 716/2014, known as Flexible Airspace Management and Free Route (FRA). The authors pose a question-does free route implementation influence air transport safety? What can be done to maintain the current level of safety and still implement modern solutions? To achieve the aim of this paper a developed concept of Risk Priority Number (RPN) calculation, with determination of main RPN components rating scales, in order to carry out the FMEA (Failure Mode and Effects Analysis) risk analysis of FRA implementation was done. The results allow lining up of the identified potential incompatibilities according to their criticality to the system. In effect it can be said that each modification in a management system, related to safety, influence the safety itself. Nevertheless, this influence does not always lead to negative impact.
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INTRODUCTION: For last several years popularity of substances which improve concentration or/and cause hallucinations has considerably increased. There is a conviction that most frequent addictions among teenagers are cigarettes, alcohol or drugs of abuse. A very dangerous phenomenon has been ignored, becoming more common among scholars and students - usage of medicines available without doctor's prescription (over the counter drugs - OTC). Popularity and fame of these specifics comes from side effects observed especially when overdosed. MATERIAL AND METHODS: In years 2007-2012 in Clinical Toxicology Laboratory of Medical Pomeranian University 4304 toxicological analyses was conducted with specified direction on drugs analysis (39% of all analyses made in that period). In some cases, especially of young people, a doctor ordering the analysis pointed as possible cause of intoxication "recreational usage" of OTC drugs. Those suspicions were confirmed by toxicological examinations. CONCLUSIONS: It seems that dominating character feature of people who abuse psychoactive substances is emotional immaturity. Maturation process can be impaired or completely inhibited by abusing psychoactive substances. This is processes are considered which enhance immaturity of person's personality - so called defense mechanisms.
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Conducta del Adolescente , Medicamentos sin Prescripción/aislamiento & purificación , Psicotrópicos/aislamiento & purificación , Detección de Abuso de Sustancias/estadística & datos numéricos , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Femenino , Humanos , Masculino , Personalidad , Polonia/epidemiología , Conducta Social , Estudiantes/estadística & datos numéricos , Trastornos Relacionados con Sustancias/psicologíaRESUMEN
Abstract: The stability of aqueous and non-aqueous papaverine hydrochloride solutions exposed to the UV radiation is poor. In order to enhance its photo-stability suitable light absorbers may be used. There werefour photo-protectors considered in this work: 4-aminobenzoic acid, sodium benzoate, methyl 4-hydroxybenzoate and propyl 4-hydroxybenzoate, whose UV absorption spectra characteristics match to some extent with the UV spectrum of papaverine. Approximately 20 mg/mL papaverine chloroform solutions with the above non-toxic additives in the concentrations 0.01; 0.05; 0.10% were exposed to the UV light of 254 nm. High performance capillary electrophoresis was used to determine the papaverine hydrochloride concentration loss as a function of time exposition to the light. It was found that papaverine hydrochloride photolysis proceeds according to the first-order kinetics. Methyl 4-hydroxybenzoate was found to be the best UV radiation-protective agent, and at the concentration 0.10%, the reaction rate constant decreases from 0.143 h(-1) to 0.028 h(-1). Both 4-hydroxybenzoate esters develop a more efficient UV radiation-protective activity than sodium benzoate, because the latter additive molar extinction coefficient is less significant. However, in spite of a high value of 4-aminobenzoic acid molar absorptivity coefficient, it is an unsuitable photo-protector for papaverine hydrochloride solutions, because its UV absorption spectrum does not match with that of papaverine.
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Papaverina/química , Calibración , Electrocromatografía Capilar , Cloroformo , Estabilidad de Medicamentos , Excipientes , Indicadores y Reactivos , Cinética , Oxidación-Reducción , Soluciones Farmacéuticas , Fotoquímica , Solventes , Espectrofotometría UltravioletaRESUMEN
We have obtained structure-activity relations for nanosphere drug delivery as a function of the chemical properties of a tunable family of self-assembling triblock copolymers. These block copolymers are synthesized with hydrophobic oligomers of a desaminotyrosyl tyrosine ester and diacid and hydrophilic poly(ethylene glycol). We have calculated the thermodynamic interaction parameters for the copolymers with anti-tumor drugs to provide an understanding of the drug binding by the nanospheres. We find that there is an optimum ester chain length, C8, for nanospheres in terms of their drug loading capacities. The nanospheres release the drugs under dialysis conditions, with release rates strongly influenced by solution pH. The nanospheres, which are themselves non-cytotoxic, deliver the hydrophobic drugs very effectively to tumor cells as measured by cell killing activity in vitro and thus offer the potential for effective parentarel in vivo delivery of many hydrophobic therapeutic agents.
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Sistemas de Liberación de Medicamentos , Nanotubos/química , Polímeros/química , Tirosina/química , Cromatografía Líquida de Alta Presión , Portadores de Fármacos/química , Concentración de Iones de Hidrógeno , Sustancias Macromoleculares/química , Modelos Químicos , Peso Molecular , Nanoestructuras , Paclitaxel/química , Polietilenglicoles/química , Relación Estructura-ActividadRESUMEN
HPCE methodology was modified to be used in kinetic experiments on photooxidation reactions of papaverine hydrochloride 1 and its oxidation products (papaverinol 2 and papaveraldine hydrochloride 3) chloroform solutions exposed to UV254 light in aerobic conditions. On photooxygenation of the above compounds is formed the final degradation product, a brown compound X 4, 2,3,9,10-tetramethoxy-12-oxo-12H-indolo[2,1-a]isoquinolinylim chloride. The rate of 4 formation from the above compounds can be given as 2>3>1>1 HCl. The photooxidation reactions of 1 and 2 proceed with pseudo first-order kinetics and that reaction for 3 follows zero-order kinetics. The most labile compound is 2 whose half-life time is 2.4 times shorter than that one of 1 HCL. The most stable product is 3 whose half-life time is 31-fold longer than of 2. The specific quantum yields are equal 0.28, 0.30 and 0.10 for 1 HCl, 2 and 3, respectively which confirm the above stability pattern of the compounds concerned.
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Cloroformo/química , Papaverina/química , Fotoquímica/métodos , Vasodilatadores/química , Interacciones Farmacológicas , Cinética , Oxidación-Reducción , Papaverina/análogos & derivadosRESUMEN
Although mouse development is regulative, the cleavage pattern of the embryo is not random. The first cleavage tends to relate to the site of the previous meiosis. Sperm entry might provide a second cue, but evidence for and against this is indirect and has been debated. To resolve whether sperm entry position relates to the first cleavage, we have followed development from fertilization by time-lapse imaging. This directly showed cytokinesis passes close to the site of the previous meiosis and to both the sperm entry site and trajectory of the male pronucleus in a significant majority of eggs. We detected asymmetric distribution of Par6 protein in relation to the site of meiosis, but not sperm entry. Unexpectedly, we found the egg becomes flattened upon fertilization in an actin-mediated process. The sperm entry position tends to lie at one end of the short axis along which cleavage will pass. When we manipulated eggs to change their shape, this repositioned the cleavage plane such that eggs divided along their experimentally imposed short axis. Such manipulated eggs were able to develop to term, emphasizing the regulative nature of their development.
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Fase de Segmentación del Huevo/fisiología , Ratones/embriología , Óvulo/citología , Espermatozoides/metabolismo , Animales , División Celular/fisiología , Tamaño de la Célula/fisiología , Cruzamientos Genéticos , Femenino , Regulación del Desarrollo de la Expresión Génica/fisiología , Inmunohistoquímica , Masculino , Microscopía por Video , Óvulo/metabolismo , Proteínas/metabolismoRESUMEN
The preimplantation development of the mammalian embryo encompasses a series of critical events: the transition from oocyte to embryo, the first cell divisions, the establishment of cellular contacts, the first lineage differentiation-all the first subtle steps toward a future body plan. Here, we use microarrays to explore gene activity during preimplantation development. We reveal robust and dynamic patterns of stage-specific gene activity that fall into two major phases, one up to the 2-cell stage (oocyte-to-embryo transition) and one after the 4-cell stage (cellular differentiation). The mouse oocyte and early embryo express components of multiple signaling pathways including those downstream of Wnt, BMP, and Notch, indicating that conserved regulators of cell fate and pattern formation are likely to function at the earliest embryonic stages. Overall, these data provide a detailed temporal profile of gene expression that reveals the richness of signaling processes in early mammalian development.
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Blastocisto/metabolismo , Tipificación del Cuerpo/genética , Diferenciación Celular/genética , Regulación del Desarrollo de la Expresión Génica/genética , Transducción de Señal/genética , Proteínas de Pez Cebra , Cigoto/metabolismo , Animales , Blastocisto/citología , Proteínas Morfogenéticas Óseas/genética , Linaje de la Célula/genética , Polaridad Celular/genética , Dermatoglifia del ADN , Femenino , Feto , Genoma , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Proto-Oncogénicas/genética , ARN Mensajero Almacenado/genética , Receptores Notch , Factores de Tiempo , Células Madre Totipotentes/citología , Células Madre Totipotentes/metabolismo , Proteínas Wnt , Cigoto/citologíaRESUMEN
The structure of the final degradation product formed in papaverine solutions in either water or chloroform was found to be a 2, 3, 9, 10-tetramethoxy-12-oxo-12H-indolo [2, 1-a] isoquinolinylium salt (a dibenzo [b, g] pyrrocolonium derivative). Its formation from papaverine oxidation products that is papaverinol, papaveraldine, and papaverine-N-oxide chloroform solutions under the influence of UV light, was investigated and possible reaction pathways are discussed.
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Indoles/química , Papaverina/efectos de la radiación , Fotólisis , Compuestos de Quinolinio/química , Química Farmacéutica , Estabilidad de Medicamentos , Oxidación-Reducción , Papaverina/química , SolucionesRESUMEN
The first cleavage of the fertilised mouse egg divides the zygote into two cells that have a tendency to follow distinguishable fates. One divides first and contributes its progeny predominantly to the embryonic part of the blastocyst, while the other, later dividing cell, contributes mainly to the abembryonic part. We have previously observed that both the plane of this first cleavage and the subsequent order of blastomere division tend to correlate with the position of the fertilisation cone that forms after sperm entry. But does sperm entry contribute to assigning the distinguishable fates to the first two blastomeres or is their fate an intrinsic property of the egg itself? To answer this question we examined the distribution of the progeny of early blastomeres in embryos never penetrated by sperm - parthenogenetic embryos. In contrast to fertilised eggs, we found there is no tendency for the first two parthenogenetic blastomeres to follow different fates. This outcome is independent of whether parthenogenetic eggs are haploid or diploid. Also unlike fertilised eggs, the first 2-cell blastomere to divide in parthenogenetic embryo does not necessarily contribute more cells to the blastocyst. However, even when descendants of the first dividing blastomere do predominate, they show no strong predisposition to occupy the embryonic part. Thus blastomere fate does not appear to be decided by differential cell division alone. Finally, when the cortical cytoplasm at the site of sperm entry is removed, the first cleavage plane no longer tends to divide the embryo into embryonic and abembryonic parts. Together these results indicate that in normal development fertilisation contributes to setting up embryonic patterning, alongside the role of the egg.
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Tipificación del Cuerpo , Fertilización , Óvulo/fisiología , Reproducción , Espermatozoides/fisiología , Animales , Blastocisto/metabolismo , División Celular , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Partenogénesis , Interacciones Espermatozoide-Óvulo , Factores de TiempoRESUMEN
The conservation of early cleavage patterns in organisms as diverse as echinoderms and mammals suggests that even in highly regulative embryos such as the mouse, division patterns might be important for development. Indeed, the first cleavage divides the fertilized mouse egg into two cells: one cell that contributes predominantly to the embryonic part of the blastocyst, and one that contributes to the abembryonic part. Here we show, by removing, transplanting or duplicating the animal or vegetal poles of the mouse egg, that a spatial cue at the animal pole orients the plane of this initial division. Embryos with duplicated animal, but not vegetal, poles show abnormalities in chromosome segregation that compromise their development. Our results show that localized factors in the mammalian egg orient the spindle and so define the initial cleavage plane. In increased dosage, however, these factors are detrimental to the correct execution of division.
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Polaridad Celular/fisiología , Embrión de Mamíferos/embriología , Meiosis/fisiología , Mitosis/fisiología , Huso Acromático/metabolismo , Animales , Segregación Cromosómica/fisiología , Señales (Psicología) , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Femenino , Proteínas Fluorescentes Verdes , Sustancias de Crecimiento/metabolismo , Inmunohistoquímica , Proteínas Luminiscentes , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Microscopía por Video , Microtúbulos/metabolismo , ARN Mensajero , Transducción de Señal/fisiología , Tubulina (Proteína)/genética , Cigoto/citología , Cigoto/crecimiento & desarrollo , Cigoto/metabolismoRESUMEN
In 1915 Gadamer published in this journal [1] a procedure for the synthesis of papaverinol 2 from papaverine 1 in excellent yield. However, he did not investigate the formation of a violet fluorescence produced upon crystallization of papaverinol 2 from ethanol. The compound responsible for this fluorescence was isolated and identified as the yet unknown quaternary ammonium ion 4, a 6a, 12a-diazadibenzo-[a, g]fluorenylium derivative. The isolation of 4 and its structure determination by spectroscopic methods are described. However, its formation mechanism is unknown.
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Papaverina/análogos & derivados , Papaverina/síntesis química , Colorantes Fluorescentes , Indicadores y Reactivos , Espectrometría de Masas , Compuestos de Mercurio/química , Oxidación-Reducción , Espectrometría de Fluorescencia , Espectrofotometría UltravioletaRESUMEN
The sperm entry position (SEP) of the mouse egg, labelled by placing a bead at the fertilisation cone, tends to be associated with the first cleavage plane (Piotrowska and Zernicka-Goetz: Nature 409:517-521, 2001). Nevertheless, in up to one-fourth of embryos the cleavage furrow did not pass close to the bead, and following the division the bead marked the cleavage plane in only 60% of cases. This raised the question of whether such variability arose from the labelling itself or had a biological basis. The zona pellucida was not responsible for this effect because similar results were obtained in its presence or absence. However, this variability could be attributable to the large size of the fertilisation cone relative to the SEP. Therefore, we have developed a means of fluorescently labelling sperm that can record the exact site of its penetration when the label transfers to the egg surface. This approach indicates that the SEP marks the first cleavage in the great majority (88%) of embryos. In conclusion, direct sperm labelling shows precisely the correlation between the SEP and the first cleavage, although there is natural variability in this process.
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Polaridad Celular/fisiología , Interacciones Espermatozoide-Óvulo , Cigoto/crecimiento & desarrollo , Animales , División Celular/fisiología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Espermatozoides/citología , Espermatozoides/fisiología , Cigoto/citologíaRESUMEN
Papaverine hydrochloride, papaverinol, and papaveraldine chloroform solutions were exposed to UV light of 254 nm in atmospheric, aerobic and anaerobic (helium) conditions. The same degradation products appear (TLC) in the above papaverine hydrochloride chloroform solutions. However, the rate of papaverine hydrochloride degradation processes is enhanced as a function of oxygen pressure. Papaverinol and papaveraldine photooxidation products are essentially not different from those observed in the above papaverine hydrochloride solutions. However, the amount of an unknown brown degradation product (X) is the greatest in the papaverinol chloroform solution degraded. That brown compound was previously observed in papaverine either hydrochloride or sulfate injection solutions on their storage even when protected from daylight. The preliminary X product structure development was undertaken (TLC, molecular weight, elemental analysis, UV/VIS, IR and 13C MAS NMR spectroscopy).