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792. A Mediterranean population of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) exhibits wing morph-related differences in adipokinetic response
- Creator:
- Kodrík, Dalibor and Socha, Radomír
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, ploštice, Pyrrhocoridae, Pyrrhocoris apterus, křídla, dimorfismus křídel, neurohormony, adipokinetické hormony, funkce, 595.2/.7, and 591.1
- Language:
- English
- Description:
- Short-winged (brachypterous) and long-winged (macropterous) adult females of Pyrrhocoris apterus (L.) originating from a Mediterranean population (Israel) were analyzed for their adipokinetic responses. The adipokinetic response, expressed as an increase of haemolymph lipids after injection of adipokinetic hormone from Locusta migratoria (Lom-AKH-I), was assessed in relation to age and dose of the hormone. We demonstrate in this study that the adipokinetic responses induced by bug's corpora cardiaca extract and Lom-AKH-I were dose-dependent for both brachypterous and macropterous females. Significant differences between the morphs were recorded for doses >= 0.25 corpora cardiaca equivalent (P < 0.01) and doses >= 0.25 pmol Lom-AKH-I (P < 0.05). The haemolymph lipid elevations induced in both morphs by 2 pmols Lom-AKH-I are comparable with that induced by crude extract of one pair of the bug's own corpora cardiaca. The age-dependent test showed much higher adipokinetic responses (P < 0.01) in macropterous females (>= 5 days old) than in the brachypterous females of the same age, when treated with 2 pmols Lom-AKH-I. Starting from day 7, the concentration of haemolymph lipids was also considerably higher (2.5-5 times) in macropterous females than in the brachypterous ones. The obtained data indicate that difference in mobilization of lipids between brachypterous and macropterous females is a geographically independent feature and represents a true wing morph characteristic of P. apterus., Dalibor Kodrík, Radomír Socha, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
793. A mesomechanical analysis of creep under different time-independent loadings
- Creator:
- Kafka, Vratislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- creep, mesomechanics, and tensorial internal variables
- Language:
- English
- Description:
- The general author‘s mesomechanical model with tensorial internal variables is applied to creep of steel 0,5Cr0,5Mo0,3V under different loading levels. It is shown that the creep process can be described by the mesomechanical model in its whole course up to rupture. However, the model parameters can be influenced at the very beginning by the application of the applied load if it is high enough to cause changes in the internal structure. This problem is specific for creep at high temperatures and significant differences in the loading levels (contrary to the small-strain plasticity studied usually at low temperatures, where the model parameters can be considered the same for different loadings). and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
794. A method for determination of one hundred endogenous steroids in human serum by gas chromatography-tandem mass spectrometry
- Creator:
- Hill, M. , Hána, V. , Velíková, M., Pařízek, A., Kolátorová, L. , Vítků, J., Škodová, T., Šimková, M. , Šimják, P. , Kancheva, R., Koucký, M. , Kokrdová, Z., Adamcová, K. , Černý, A. , Hájek, Z., Dušková, M., Bulant, J., and Stárka, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Steroid metabolome, Human blood, Gas chromatographytandem mass spectrometry, Backdoor pathway, Pregnancy, and Mixed umbilical cord blood
- Language:
- English
- Description:
- Steroid profiling helps various pathologies to be rapidly diagnosed. Results from analyses investigating steroidogenic pathways may be used as a tool for uncovering pathology causations and proposals of new therapeutic approaches. The purpose of this study was to address still underutilized application of the advanced GC-MS/MS platform for the multicomponent quantification of endogenous steroids. We developed and validated a GC-MS/MS method for the quantification of 58 unconjugated steroids and 42 polar conjugates of steroids (after hydrolysis) in human blood. The present method was validated not only for blood of men and non-pregnant women but also for blood of pregnant women and for mixed umbilical cord blood. The spectrum of analytes includes common hormones operating via nuclear receptors as well as other bioactive substances like immunomodulatory and neuroactive steroids. Our present results are comparable with those from our previously published GC-MS method as well as the results of others. The present method was extended for corticoids and 17α-hydroxylated 5α/β-reduced pregnanes, which are useful for the investigation of alternative “backdoor” pathway. When comparing the analytical characteristics of the present and previous method, the first exhibit by far higher selectivity, and generally higher sensitivity and better precision particularly for 17α-hydroxysteroids.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
795. A method for measuring coalbed methane content in coal strata without the loss of the gas
- Creator:
- Nazimko , Victor
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- coal strata, coalbed methane, exploration, gas content, measurement, lost gas, and coal mine safety
- Language:
- English
- Description:
- This paper describes an invented method for direct measurement of coalbed methane content in situ. In contrast to known procedures, this method does not need to place a rock or drilling cuts into an airtight canister, and does not involve sealing of the hole. Moreover, the new method is monitoring methane content in situ continuously and synchronously during drilling the hole not losing any portion of the gas. These positive features are a sequel of new approach based on injection of known portion of neutral gas into the hole. Methane content was determined from concentration of the mixture ‘methane-neutral gas´ at the hole´s mouth. New method is applicable for commercial recovery application of coalbed methane and forecast of dangerous gas and coal bursts. FLAC3D computer simulation helped to investigate dynamics of methane outflow from the hole to account for the effect of drilling speed on the rate of gas emanation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
796. A method of fine-grained short text sentiment analysis based on machine learning
- Creator:
- Chang, Guoqin and Huo, Hua
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fine-grained sentiment analysis, sentiment information classification, feature extraction, and weight calculation
- Language:
- English
- Description:
- Text sentiment analysis plays an important role in social network information mining. It is also the theoretical foundation and basis of personalized recommendation, circle of interest classification and public opinion analysis. In view of the existing algorithms for feature extraction and weight calculation, we find that they fail to fully take into account the in fluence of sentiment words. Therefore, this paper proposed a fine-grained short text sentiment analysis method based on machine learning. To improve the calculation method of feature selection and weighting and proposed a more suitable sentiment analysis algorithm for features extraction named N-CHI and weight calculation named W-TF-IDF, increasing the proportion and weight of sentiment words in the feature words Through experimental analysis and comparison, the classification accuracy of this method is obviously improved compared with other methods.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
797. A Method of forecasting earthquake by optical astronomic time-latitude residuals
- Creator:
- Su, Youjin, Gao, Yuping, and Hu, Hui
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geomechanika, geofyzika, geologie, zemětřesení, geodynamics, geomechanics, geophysics, geology, earthquake, optical astronomic time-latitude residuals, change of the plumb line, motion of the groundmass, 7, and 551
- Language:
- English
- Description:
- This article reports a method for forecasting an earthquake by synchronous anomalies of optical astronomic time-latitude residuals. The so-called optical astronomic time-latitude residuals for a certain astrometric instrument are the rest after deducting the effects of Earth whole motion from the astronomical time and latitude observations determined by the instrument. Forecasting practice for four earthquakes around the Yunnan Observatory occurring after 2010 shows that it does not generate false forecasts, and also does not miss forecasts of major earthquakes. This forecasting practice proves that the synchronous anomalies of astronomical time-latitude residuals can provide effective warning sign for earthquake occurrence around observatory station, thus deserves attention and further study. and Su Youjin, Gao Yuping, Hu Hui.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
798. A method of resolution improvement by the measurement of cell membrane capacitance
- Creator:
- Rech, F., Rohlíček, V., and Schmid, A.
- Type:
- article, model:article, and TEXT
- Subject:
- patch-clamp technique, membrane capacitance, membrane, conductance, series resistance, exocytosis, and dual-frequency method
- Language:
- English
- Description:
- When measuring cell membrane electrical capacitance in whole cell configuration using alternating currents, the resolution decreases with increasing membrane conductance and pipette resistance. Improved resolution was attained by the dual-frequency method which was modified as to control the voltage amplitude of one of the measuring frequencies. A model circuit was developed for the verification of the method. This circuit allows measurement of calibrated capacitance changes even in the range of 5 to 20 fF. Moreover, the method was applied to capacitance measurements on pancreatic exocrine acinar cells. The results of measurements on the model as well as on pancreatic acinar cells are presented. The principle can also be applied to other hardware and software methods for measuring electrical cell membrane parameters.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
799. A method with enhanced sensitivity for temperature measurement in living tissues
- Creator:
- Rech, F., Dittert, I., and Rohlíček, V.
- Type:
- article, model:article, and TEXT
- Subject:
- microsensor, temperature measurement, and electrical admittance measurement
- Language:
- English
- Description:
- A system for the evaluation of temperature changes in living tissue at a dimensional level of a single cell is described. A glass micropipette the tip of which is filled with semiconducting glass (Rech et al. 1992), is used as a microsensor. The changes of conductivity of the sensor due to variations of temperature are evaluated by electronic circuitry based on the measurement of an AC current of sinusoidal waveform flowing through the sensor. Temperature changes in the range of 0.01 K can be detected in this way.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
800. A microsporidian parasite of the genus Spraguea in the nervous tissues of the Japanese anglerfish Lophius litulon
- Creator:
- Freeman, Mark A., Yokoyama, Hiroshi, and Ogawa, Kazuo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Spraguea, microsporidia, Lophius, and nervous tissue
- Language:
- English
- Description:
- In the present study, a high percentage of Japanese anglerfish, Lophius litulon (Jordan, 1902), contained a microsporidian infection of the nervous tissues. Xenomas were removed and prepared for standard wax histology and transmission electron microscopy (TEM). DNA extractions were performed on parasite spores and used in PCR and sequencing reactions. Fresh spores measured 3.4 × 1.8 µm and were uniform in size with no dimorphism observed. TEM confirmed that only a single developmental cycle and a single spore form were present. Small subunit (SSU) rDNA sequences were >99.5% similar to those of Spraguea lophii (Doflein, 1898) and Glugea americanus (Takvorian et Cali, 1986) from the European and American Lophius spp. respectively. The microsporidian from the nervous tissue of L. litulon undoubtedly belongs in the genus Spraguea Sprague et Vávra, 1976 and the authors suggest a revision to the generic description of Spraguea to include monomorphic forms and the transfer of Glugea americanus to Spraguea americana comb. n. Since no major differences in ultrastructure or SSU rDNA sequence data exist between Spraguea americana and the microsporidian from the Japanese anglerfish, they evidently belong to the same species. This report of Spraguea americana is the first report of a Spraguea species from L. litulon and indeed from the Pacific water mass.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public