This case study presents the verification of two surface subsidence prediction models for longwall mining at depths greater than 400 m. The surface subsidence points were surveyed and compared for both models. The first model uses empirical calculations to predict the surface subsidence. This method is reliable for predicting surface subsidence at shallower depths. At present, however, coal mining has progressed to great depths. The second model is the 2-dimensional finite element method to predict surface subsidence. In contrast to the first method, this method is based on the regional parameters and uses the rock mass properties to evaluate surface subsidence for multi-seams at any depth. Results show that the finite element method gives a better approximation of the measured surface subsidence than the Knothe method. The maximum surface subsidence, which was determined by the FEM method, was used to adjust the extraction coefficient in the Knothe's method. The predicted value differs from the measured value by 8 %. The slope of the predicted subsidence trough was within the range of 2‒8 % from the surveyed subsidence. This case study proposes a procedure for using both models to successfully predict the surface subsidence.
Performance of 24h static Precise Point Positioning (PPP) solutions based on multi-GNSS precise satellite orbit and clock products from four analysis centers and seven various constellation combinations was studied to evaluate their quality and characteristics. Data from ten European and four Chinese GNSS stations and 152 days long period from year 2020 were processed. Obtained coordinates were firstly compared with those provided by IGS final weekly combined solution. In Europe, the best agreement with this reference product was reached by solutions including Galileo signals, namely by a combination of GPS+GLONASS+Galileo systems with a mean RMS of 11 mm. This situation was different in China where inclusion of Galileo always led to worse results and the best agreement was achieved by a combination of GPS+GLONASS systems. Although product provided by German Research Center for Geosciences (GFZ) could be selected as the best performing over Europe and product by Center for Orbit Determination in Europe (CODE) over China, differences between individual precise products were mostly at a minimal level. Secondly, coordinates repeatability over the processed period was computed in order to assess the positioning stability. In this regard, the lowest values in both horizontal and vertical direction were reached by GPS+GLONASS solutions. From the perspective of precise products, the repeatability results were dependent on the selected constellation where mainly a specific behavior of product from Wuhan University (WUM) for Galileo system was observed., Weiguo Li and Michal Kačmařík., and Obsahuje bibliografii
A method for estimation of elastic wave velocity anisotropy based on ultrasonic sounding data during rock-sample loading was developed. The subject matter of the method is approximation of ultrasonic sounding data by triaxial velocity ellipsoid. The applicability of proposed method was verified on investigation of anisot ropic rock samples. Laboratory loading of migmatite samples was realized under various mutual orientations between acting force direction and rock foliation - perpendicular, parallel and under 45°. P-ve velocity of ultrasound waves was monitored by 8 sensors network. The velocity ellipsoid was computed and changes of sizes and waorientation its main axes during loading were analyzed for separate experiments with regard to loading level. It was found, that independently to mutual orientation between rock foliation and loading direction, the minimum velocity vector turns to perpendicular direction to final rupture plane and maximum velocity vector turns to the plane of final rupture., Matěj Petružálek, Jan Vilhelm, Tomáš Lokajíček and Vladimír Rudajev., and Obsahuje bibliografické odkazy
Patients suffering from Parkinson's disease must periodically undergo a series of tests, usually performed at medical facilities, to diagnose the current state of the disease. Parkinson's disease progression assessment is an important set of procedures that supports the clinical diagnosis. A common part of the diagnostic train is analysis of speech signal to identify the disease-specific communication issues. This contribution describes two types of computational models that map speech signal measurements to clinical outputs. Speech signal samples were acquired through measurements from patients suffering from Parkinson's disease. In addition to direct mapping, the developed systems must be able of generalization so that correct clinical scale values can be predicted from future, previously unseen speech signals. Computational methods considered in this paper are artificial neural networks, particularly feedforward networks with several variants of backpropagation learning algorithm, and adaptive network-based fuzzy inference system (ANFIS). In order to speed up the learning process, some of the algorithms were parallelized. Resulting diagnostic system could be implemented in an embedded form to support individual assessment of Parkinson's disease progression from patients' homes.
Ilona Hromadnikova, Lenka Dvorakova, Katerina Kotlabova, Andrea Kestlerova, Lucie Hympanova, Veronika Novotna, Jindrich Doucha, Ladislav Krofta and Literatura
Mitochondrial dysfunction is currently acknowledged as a central
pathomechanism of most common diseases of the 21st century.
Recently, the assessment of the bioenergetic profile of human
peripheral blood cells has emerged as a novel research field with
potential applications in the development of disease biomarkers.
In particular, platelets have been successfully used for
the ex vivo analysis of mitochondrial respiratory function in
several acute and chronic pathologies. An increasing number of
studies support the idea that evaluation of the bioenergetic
function in circulating platelets may represent the peripheral
signature of mitochondrial dysfunction in metabolically active
tissues (brain, heart, liver, skeletal muscle). Accordingly,
impairment of mitochondrial respiration in peripheral platelets
might have potential clinical applicability as a diagnostic and
prognostic tool as well as a biomarker in treatment monitoring.
The aim of this minireview is to summarize current information in
the field of platelet mitochondrial dysfunction in both acute and
chronic diseases.
An expedition was undertaken to French Guiana in search of amphibian parasites. Of the 23 anuran species collected and screened for polystomes, the toad Rhinella margaritifera (Laurenti) was the sole species found to be infected with a polystome, namely Wetapolystoma almae Gray, 1983. Of the two caecilian species collected, a new species of Nanopolystoma du Preez, Huyse et Wilkinson, 2008 was discovered from the urinary bladder of the aquatic caecilian Typhlonectes compressicauda (Duméril et Bibron). The small size of the mature worm, two non-diverticulated caeca of equal length that are non-confluent posteriorly, vitelline follicles in two dense lateral fields, a single follicular testis in the middle of the body, small ovary and a single operculated egg in utero, vaginae present and the caecilian host allowed the identification of the specimen as Nanopolystoma. Larger body size, hamulus length, egg diameter and occurrence in the caecilian family Typhlonectidae distinguishes the new species from the two other known polystomes in Nanopolystoma; thus, the description of Nanopolystoma tinsleyi sp. n. is provided within this paper.
In the present study physicochemical characterization of slate sample was carried out which was collected from slate mine in Lasbela District, Baluchistan. Slate was evaluated for its effectiveness as partial replacement of ordinary Portland cement (OPC) in the production of Portland Pozzolana cement (PPC). The grain size analysis of crushed slate sample using ball mill revealed that maximum fraction retained on 44 μm was about 72.8 %. Sum of the major oxides (SiO2 + Al2O3 + Fe2O3) is about 90.09 % that meet the requirement as per ASTM C 618 (minimum 70.0 %). Other oxides including SO3 (<0.05), CaO (4.04), MgO (1.66), K2O (0.10), Na2O (0.16), TiO2 (0.35), MnO (<0.02) and Cl (0.12) also meet the international standard of ASTM C 618 for PPC. OPC without and with using slate sample in a ratio of 5 % and 10 % with clinker was tested to measure compressive strength, physical tests and setting time. The results showed that after 5 % and 10 % replacement, insignificant effect was observed on the physical properties, setting time and compressive strength in 2-, 7- and 28-days curing. Hence, slate can be used as natural pozzolan for manufacturing PPC. It is cost effective for the production of cement as well as to sustain the resources of limestone for long time and reducing emission of CO2 in the environment. It can also be used in the sulfate rich environment, coastal areas especially for the construction of dams and bridges.
Cíl: Převod Testu paměti pro záměry (Memory for Intentions (Screening) Test; MIST, 2010) do české verze zahrnoval standardizaci pomůcek, převod administrace a skórování, validační studii na české populaci, aby MIST bylo možné použít na české populaci. Úvod: Konstrukt prospektivní paměti (PP), tj. schopnosti si zapamatovat a realizovat záměry, je nezbytný pro uchování soběstačnosti, vykonávání aktivit denního života. V posledních letech hraje čím dál významnější roli pro diagnostiku poruch paměti. Standardizovaná a validovaná měřítka PP však v české diagnostice chybí. Metodika: Český převod MIST jsme administrovali 30 zdravým osobám. Výsledky: Celkový skór PP v testu MIST koreloval na střední úrovni s měřítky z neuropsychologické baterie zejména s retencí v paměti, mentální flexibilitou, odolností k interferenci a premorbidní inteligenční úrovní (všechna rho = 0,37–0,42, všechna p < 0,05). Reliabilita testu MIST ve smyslu vnitřní konzistence byla u základních osmi subškál nedostatečná (α = 0,50) i ve smyslu reliability obou polovin testu (split‑half reliabilita = 0,56), avšak reliabilita šesti subškál tříděných dle typu (oddálení, vodítka a modality odpovědi) byla vysoká (α = 0,88; split‑half = 0,95). Závěr: Výsledky validační studie naznačují, že český převod MIST je srovnatelný s verzí originální. Studie zpřístupňuje standardní vyšetření PP a umožňuje měření PP na klinických populacích. Klíčová slova: Test paměti pro záměry – prospektivní paměť – deklarativní paměť – validita – reliabilita – epizodická paměť <h3>Přílohy</h3> <a href="/dokumenty/CSNN2014_3_Bezdicek_prilohy_TK.pdf"> 1. Instrukce Testu paměti pro záměry (MIST)</a> <a href="/dokumenty/CSNN2014_3_Bezdicek_prilohy_TK_2.pdf">2. Test na prospektivní paměť (MIST) a jeho administrace</a>, Aim: The goal of the present study was to validate the Czech version of the Memory for Intentions (Screening) Test (MIST, 2010). We included standardized testing material, translation of administration and scoring, and assessment of normative data for the MIST in the Czech population. Introduction: Prospective memory (PM), i.e., the ability to remember and implement intentions after a delay, is essential as a subsystem of episodic memory for the maintenance of independence and execution of activities of daily living. PM assessment thus plays an important role in the diagnosis of episodic memory disorders. However, there are currently no standardized and validated PM tools in Czech language. Methods: The Czech version of MIST was administered to 30 healthy persons. Results: The MIST Summary score correlated at a medium level with a range of neuropsychological measures including memory retention, mental flexibility, and resistance to interference (all rho = 0.37–0.42; all p < 0.05). The reliability of MIST in terms of internal consistency was insufficient when analyzing the eight individual MIST trials (α = 0.50), as was split‑half reliability (split‑half reliability = 0.56). In contrast, there was a high degree of reliability between six subscales classified by type (delay, cue and mode of response; α = 0.88, split‑half = 0.95). Conclusion: The reliability and validity of the Czech version of MIST is comparable to the original English version. The study opens access to standardized PM assessment in clinical populations in the Czech Republic., Na webových stránkách: www.csnn.eu naleznete další přílohy k tomuto článku., and O. Bezdicek, S. A. Raskin, M. Altgassen, E. Ruzicka