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To support the conservation efforts regarding a wooden church in Domachowo, extensive research and design work was required to strengthen its weakened structure. A variety of data and analyses are necessary to make an accurate assessment, including obtaining a dimensional model, monitoring the behavior of the structure and its response to external forces, and also performing strength analyses and verifying them with measurement data. For accurate geometric evaluation, static and dynamic measurements were required. A mathematical model and a flowchart of the necessary tasks were developed, along with the selection and installation of measuring devices. For this particular structure, static measurements were made using an automatic total station, and dynamic measurements using tilt sensors. The purpose of the analysis was to correlate the inertia measurements with the absolute tachymetric observations related to reference points fixed outside the object in order to accurately assess the behavior of the object. Another important issue was to model the column element under study in such a way that its horizontal displacements could be determined from the measured inclinations. The obtained results indicated the need to strengthen the joints of the two main parts of the structure in order to minimize the impact of dynamic weather conditions. The paper describes the measurement process, the method of calculating displacements, and the correlation of both types of data. Selected results confirming the conclusions are also presented.
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In this study, composites containing polylactide and carbonate lake sediment in concentrations of 2.5, 5, 10, and 15% by weight were prepared by a 3D printing method. The material for 3D printing was obtained by directly diluting the masterbatch on an injection moulder to the desired concentrations, and after granulation, it was extruded into a filament. The material prepared thusly was used to print standardised samples for mechanical testing. To compare the mechanical properties of the composites obtained by 3D printing and injection moulding, two sets of tests were performed, i.e., mechanical tests (tensile strength, flexural strength, and impact strength) and hydrophobic-hydrophilic surface character testing. The degree of composite waste in the 3D printing was also calculated. Mechanical and surface tests were performed for both systems conditioned at room temperature and after accelerated ageing in a weathering chamber. The study showed differences in the properties of composites obtained by 3D printing. Sedimentary fillers improved the hydrophobicity of the systems compared with pure PLA, but it was not a linear relationship. The PLA/CLS sedB composite had higher strength parameters, especially after ageing in a weathering chamber. This is due to its composition, in which, in addition to calcite and silica, there are also aluminosilicates, causing a strengthening of the PLA matrix.
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In this study, the influence of carbonate lake sediments (Polylactide/Carbonate Lake Sediments-PLA/CLS) on the mechanical and structural properties of polylactide matrix composites was investigated. Two fractions of sediments originating from 3-8 and 8-12 m were analysed for differences in particle size by distribution (Dynamic Light Scattering-DLS), phase composition (X-ray Diffraction-XRD), the presence of surface functional groups (Fourier Transform-Infrared-FT-IR), and thermal stability (Thermogravimetric Analysis-TGA). Microscopic observations of the composite fractures were also performed. The effect of the precipitate fraction on the mechanical properties of the composites before and after conditioning in the weathering chamber was verified through peel strength, flexural strength, and impact strength tests. A melt flow rate study was performed to evaluate the effect of sediment on the processing properties of the PLA/CLS composite. Hydrophobic-hydrophilic properties were also investigated, and fracture analysis was performed by optical and electron microscopy. The addition of carbon lake sediments to PLA allows for the obtention of composites resistant to environmental factors such as elevated temperature or humidity. Moreover, PLA/CLS composites show a higher flow rate and higher surface hydrophobicity in comparison with unmodified PLA.
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PURPOSE: Gram-negative rods of the genus Serratia play an increasing role as etiological agents of healthcare-associated infections (HAI) in humans. These bacteria are characterized by natural and acquired resistance to several groups of antibacterial agents. The aim of the study was to characterize class 1, 2 and 3 integrons in the clinical isolates of Serratia spp. in Poland. METHODS: The study comprised 112 clinical strains of Serratia, isolated from patients hospitalized in Poland in 2010-2012. Identification of strains was confirmed using MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) system. Detection of class 1, 2 and 3 integrase DNA sequence was performed by multiplex-PCR. Amplicons obtained in the PCR reactions were purified and then sequenced bidirectionally. RESULTS: Among the analyzed strains, Serratia marcescens was a predominant species (103/112, 92.0%). All three classes of integrase DNA sequence were detected in the analyzed strains of Serratia spp. DNA sequence of class 3 integron, besides integrase gene, revealed three gene cassettes (dfrB3, bla GES-7,bla OXA/aac(6')-Ib-cr). BLAST analysis of DNA sequence revealed that class 3 integron was carried on 9448 bp plasmid which was named pPCMI3 - whole sequence of its DNA was submitted to GenBank NCBI (National Center for Biotechnology Information) - NCBI MH569711. CONCLUSION: In this study, we identified a new plasmid pPCMI3 harboring class 3 integron. This is the first report of a gene oxa/aac(6')-Ib-cr coding for a novel fusion protein, which consists of OXA ß-lactamase and acetyltransferase aac(6')-Ib-cr. In the analyzed strains, class 1 and 2 integrons were also detected. Among the strains with class 1 integron, nine contained cassette array 5'CS-aadA2-ORF-dfrA12-3'CS, and two - cassette array 5'CS-aacC1-ORF-ORF-aadA1-3'CS, which were not previously reported in Serratia spp.
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OBJECTIVES: Cervical vestibular evoked myogenic potentials (cVEMP) indirectly reveal the response of the saccule to acoustic stimuli through the inhibition of sternocleidomastoid muscle electromyographic response. VEMP inhibition depth (VEMPid) is a recently developed metric that estimates the percentage of saccular inhibition. VEMPid provides both normalization and better accuracy at low response levels than amplitude-normalized cVEMPs. Hopefully, VEMPid will aid in the clinical assessment of patients with vestibulopatholgy. To calculate VEMPid a template is needed. In the original method, a subject's own cVEMP was used as the template, but this method can be problematic in patients who do not have robust cVEMP responses. We hypothesize that a "generic" template, created by assembling cVEMPs from healthy subjects, can be used to compute VEMPid, which would facilitate the use of VEMPid in subjects with pathological conditions. DESIGN: A generic template was created by averaging cVEMP responses from 6 normal subjects. To compare VEMPid calculations using a generic versus a subject-specific template, cVEMPs were obtained in 40 healthy subjects using 500, 750, and 1000 Hz tonebursts at sound levels ranging from 98 to 123 dB peSPL. VEMPids were calculated both with the generic template and with the subject's own template. The ability of both templates to determine whether a cVEMP was present or not was compared with receiver operating characteristic curves. RESULTS: No significant differences were found between VEMPid calculations using a generic template versus using a subject-specific template for all frequencies and sound levels. Based on the receiver operating characteristic curves, the subject-specific and generic template did an equally good job at determining threshold. Within limits, the shape of the generic template did not affect these results. CONCLUSIONS: A generic template can be used instead of a subject-specific template to calculate VEMPid. Compared with cVEMP normalized by electromyographic amplitudes, VEMPid is advantageous because it averages zero when there is no sound stimulus and it allows the accumulating VEMPid value to be shown during data acquisition as a guide to deciding when enough data has been collected.
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Sáculo e Utrículo/fisiologia , Potenciais Evocados Miogênicos Vestibulares , Adulto , Análise de Variância , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Doenças Vestibulares/diagnóstico , Adulto JovemRESUMO
BACKGROUND: Electro-oxidation of methanol in acidic solution was investigated on a Pt/SnO2 based electrocatalyst obtained by the sol-gel method. Pt/SnO2 systems were prepared by one pot synthesis using a sol-gel method and tin (IV) acetate as a precursor of SnO2 and water solution of hexachloroplatinum acid as a source of metallic phase. RESULTS: The described method, thanks to its simplicity and mildprocessing temperature, offers uniform dispersion of metal phase in the bulk of the gel forming as a result of hydrolysis and condnastionon of tin precursor. It has been found that the obtained system exhibits high electrocatalytic activity just after low temperature processing. This work investigates the effect of the Pt concentration and the influence thermal treatment of Pt/SnO2 on its electrochemical activity. CONCLUSIONS: The described procedure is a simple method of producing a highly active Pt/SnO2 electrocatalyst without using thermal treatment in reducing conditions. The oxidation state of Pt is a determining factor for its activity in an electrooxidation process. Graphical AbstractOne-pot method of synthesis of Pt/SnO2 catalyst.
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A hiccup is involuntary, paroxysmal inspiratory movements of the chest wall associated with diaphragm and accessory respiratory muscle contractions, with the synchronized closure of glottis. The mechanism underlying this common primitive reflex plays an important role in protecting airways against esophageal aspiration. The hiccup reflex mechanism is based on the afferent pathway (vagus and phrenic nerve and sympathetic fibers innervating chest organs, the abdomen, the ear, the nose and the throat stimulation, and the stimulation of hiccup center in the central nervous system, mainly reflecting psychogenic or metabolic disorders) and the efferent pathway (phrenic nerves). An incidental hiccup is a common problem, usually resolves spontaneously and does not present a clinical issue. The clinical issue arises in the case of pathologic persistent hiccups or symptomatic secondary hiccups which may lead to significant fatigue, insomnia or depression. Generally, pathologic hiccups are associated with considerable discomfort concerning both the "stigmatized" person and his or her personal surroundings in which it evokes different emotions, from amusement through impatience to uneasiness and the suggestion of a medical visit as an expression of concern for a given person. The most common causes of pathologic symptomatic hiccups are nervous system diseases, either the central nervous system (proliferative, angiogenic, inflammatory disorders), or the peripheral nervous system: the irritation of the phrenic nerve (proliferative disorders, goitre) and the vagus nerve (otolaryngologic diseases, meningitis, esophageal, stomach and duodenal diseases, hepatitis, pancreatitis, enteritis). The vagus nerve irritation with subsequent hiccups may be caused by chest disorders (injury, surgery) and heart diseases (myocardial infarction). In the present paper we describe the case of a 62-year-old male with recurrent hiccups associated with exertion as a secondary symptom of myocardial ischemia.