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68762. The use of morphometric characters to discriminate specimens of laboratory-reared and wild populations of Gyrodactylus salaris and G. thymalli (Monogenea)
- Creator:
- Shinn, Andrew P., Hansen, Haakon, Olstad, Kjetil, Bachmann, Lutz, and Bakke, Tor A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gyrodactylus salaris, parasite, salmyonids, taxonomy, and morphology
- Language:
- English
- Description:
- Gyrodactylus thymalli Žitňan, 1960 and G. salaris Malmberg, 1957 have an indistinguishable ribosomal internal transcribed spacer (ITS) DNA sequence, but exhibit surprisingly high levels of intra- and interspecific sequence variation of the mitochondrial cytochrome oxidase I (CO1) gene. To test whether different populations of these reportedly very similar species could be discriminated using morphometric methods, we examined the morphometry of four different populations representing different mitochondrial clades. Twenty five point-to-point measurements, including five new characters of the attachment hooks, were recorded from three Norwegian laboratory populations (G. salaris from the Rivers Lierelva and Rauma, and G. thymalli from the River Rena), and from one wild population of G. thymalli from the River Test, UK. The Norwegian populations were kept under identical environmental conditions to control for the influence of temperature on the haptoral attachment hooks. Data were subsequently subjected to univariate and linear stepwise discriminant analyses. The model generated by the linear stepwise discriminant analysis used 18 of the 25 original variables, the first two roots accounting for 96.6% of the total variation between specimens. The hamulus shaft length accounts for 66.7% of the overall correct classification efficiency. Based on morphometry, all specimens were assigned to the correct species. Apart from three specimens of G. salaris from the River Lierelva population which were misclassified as belonging to the G. salaris Rauma population, all specimens were assigned to the correct population. Thus, populations of Gyrodactylus identified by mtDNA can also be discriminated using morphometric landmark distances.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68763. The use of optoelectronic techniques in studies of relative displacements of rock mass
- Creator:
- Ćmielewski, Kazimierz, Kuchmister, Janusz, Gołuch, Piotr, and Kowalski, Krzysztof
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, optoelektronika, optoelectronics, optoelectronic techniques, studies of relative displacements, 7, and 551
- Language:
- English
- Description:
- This paper describes a prototype of the authors own design used to measure the relative inclinations of engineering objects and inanimate nature phenomena. A set of measurements can be used to determine ground surface deformation caused by mining activities or due to influences of hydro-geological, geotechnical or construction. The instrument was built with elements of the optoelectronic technique. Fiber optic, CCD camera and semiconductor laser are the basic building blocks of the device. The elaborated device runs on a Central Registration and Data Processing (CRP D) System. The deflection of freely suspended fiber are recorded by a CCD camera and next are transmitted to an external recorder (eg. notebook). Natural light or laser light was introduced into the fiber. The length of the fiber and the optical construction affects the measuring range of the device. The accuracy of instruments depends on: method of fiber suspension, method of fiber attenuation fluctuations, resolution CCD camera and identification method of the image laser spot recorded. Experiments have shown that the built prototype device is able to obtain a submillimetre accuracy., Kazimierz Ćmielewski, Janusz Kuchmister, Piotr Gołuch and Krzysztof Kowalski., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68764. The use of permanent and epoch GPS coordinate time series in geodynamic investigations of Sudetes area: proposal of a new approach
- Creator:
- Kontny, Bernard, Bosy, Jarosław, and Borkowski, Andrzej
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, GPS sítě, GPS netwoks, Krkonošsko-jesenická soustava (pohoří), Sudety mountains, recent tectonic movements, GPS time series, semipermament GPS stations, 7, and 551
- Language:
- English
- Description:
- The future of the global and local geodynamic researches belongs to permanent monitoring. The conception of the semipermanent GPS observations’ application in geodynamic research in Sudetes area is presented in this paper. The conception is based on spatial modeling of the disturbing phenomena in the coordinate time series of (semi) permanent stations. The local interplate movements and their correlation with major European tectonic structures are determined on the strength of coordinate time series of these stations. The problem of epoch integration with semipermanent and permanent (EPN/IGS) observations for local geodynamic monitoring is also investigated., Bernard Kontny, Jarosław Bosy and Andrzej Borkowski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68765. The use of poly R-478 as a marker to determine gastric emptying and intestinal propulsive motility in suckling rats
- Creator:
- Shinohara, H., Williams, C., and Koldovský, O.
- Type:
- article, model:article, and TEXT
- Subject:
- gastric emptying, intestinal propulsive motility, suckling rats, gastrointestinal motility, and new method
- Language:
- English
- Description:
- During our studies on gastrointest-inal motility in suckling rats using 51Cr or 51Cr-EDTA as markers, we noticed that these markers - in contrast to studies in adult rats "adhered" to the gastrointestinal wall of sucklings. We therefore decided to test the use of another non-absorbable marker Poly R-478 (an acetylated anthrapyridone chromophore linked to an polyamino-ethylene-sodium ethylene sulfonate copolymer backbone developed by the Dynapol Corporation (Palo Alto, CA). This new method has appeared to be useful.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68766. The use of RAPD markers to detect genetic patterns in Aleurodicus dispersus (Hemiptera: Aleyrodidae) populations from the Canary Islands
- Creator:
- Callejas, Carmen, Beitia, Fracisco J., Gobbi, Antonio, Velasco, Ana, and Ochando, Dolores M.
- Type:
- article, model:article, and TEXT
- Subject:
- Aleurodicus dispersus, spiralling whitefly, RAPD-PCR, genetic variability, and colonization
- Language:
- English
- Description:
- Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae), a highly polyphagous species, has since the 90's been an important pest of ornamentals and tropical crops in the Canary Islands. In this study the RAPD-PCR technique was used to study the genetic structure of this whitefly in this archipelago. A total of 68 different bands were scored in seven populations using six primers for amplification. No differences in RAPD patterns were found among populations from different islands of the Canaries. These findings indicate a very high genetic similarity among populations and low level of genetic variability and support a single colonization event by few A. dispersus whiteflies and recent dispersion throughout the archipelago.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68767. The use of sar interferometry for the study of landslips in the Polish Flysch Carpathians
- Creator:
- Mirek, Katarzyna
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, satellite remote sensing, InSAR, landslips, 7, and 551
- Language:
- English
- Description:
- The article discusses techniques for interpreting satellite images, which are capable of detecting and monitoring landslip zones, and presents a research plan for the study of landslips with the use of satellite interferometry. The exceptionally longlasting and heavy rainfall that occurred in 1997 initiated more than 20,000 landslips within the Polish Carpathians. These landslips continue to pose a threat. Some of them move almost imperceptibly - slowly but continually - yet long-lasting periods of heavy rainfall can lead to catastrophe. The price can be human lives, as well as losses into the millions connected with the devastation of technical infrastructures and entire housing estates. The sheer number of landslips that occur in the Polish Carpathians makes the traditional ways of researching them insufficient. Satellite remote sensing allows capturing a large area of interest on a single photo. Many various satellites photograph the surface of the Earth using different techniques, allowing for the selection of the best-suited image type for a given application. Synthetic Aperture Radar (SAR) images are utilized in landslip studies. The images may be interpreted using the InSAR and/or PSInSAR techniques. Both methods are capable of detecting landslip zones and monitoring them in order to assess the risk of a sudden landslide. Information of this type is significant to local authorities when planning the activities necessary to protect the safety of inhabitants and the local technical infrastructure., Katarzyna Mirek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68768. The use of self-organizing feature map networks for the prediction of the critical factor of safety of an artificial slope
- Creator:
- Erzin , Y., Nikoo, M., and Cetin , T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- critical factor of safety, earthquake forces, pseudo-statistic approach, Self Organization Feature Map, and simplified Bishop method
- Language:
- English
- Description:
- In this study, the performance of three different self organization feature map (SOFM) network models denoted as SOFM1, SOFM2, and SOFM3 having neighborhood shapes, namely, SquareKohonenful, LineKohonenful, and Diamond-Kohenenful, respectively, to predict the critical factor of safety (Fs) of a widely-used artificial slope subjected to earthquake forces was investigated and compared. For this purpose, the reported data sets by Erzin and Cetin (2012) [7], including the minimum (critical) Fs values of the artificial slope calculated by using the simplified Bishop method, were utilized in the development of the SOFM models. The results obtained from the SOFM models were compared with those obtained from the calculations. It is found that the SOFM1 model exhibits more reliable predictions than SOFM2 and SOFM3 models. Moreover, the performance indices such as the determination coefficient, variance account for, mean absolute error, root mean square error, and the scaled percent error were computed to evaluate the prediction capacity of the SOFM models developed. The study demonstrates that the SOFM1 model is able to predict the Fs value of the artificial slope, quite efficiently, and is superior to the SOFM2 and SOFM3.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
68769. The use of sodium polytungstate as an X-ray contrast agent to reduce the beam hardening artifact in hydrological laboratory experiments
- Creator:
- Nakashima, Yoshito
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- beam hardening artifact, contrast agent, Darcy flow, porous media, sodium polytungstate (SPT), and X-ray CT
- Language:
- Slovak
- Description:
- Iodine is conventionally used as a contrast agent in hydrological laboratory experiments using polychromatic X-ray computed tomography (CT) to monitor two-phase Darcy flow in porous geological media. Undesirable beam hardening artifacts, however, render the quantitative analysis of the obtained CT images difficult. CT imaging of porous sand/bead packs saturated with iodine and tungsten-bearing aqueous solutions, respectively, was performed using a medical CT scanner. We found that sodium polytungstate (Na6H2W12O40) significantly reduced the beam hardening compared with potassium iodide (KI). This result is attributable to the location of the K absorption edge of tungsten, which is nearer to the peak of the polychromatic X-ray source spectrum than that of iodine. As sodium polytungstate is chemically stable and less toxic than other heavy element bearing compounds, we recommend it as a promising contrast agent for hydrological CT experiments.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
68770. The usefulness of chromosomes of parasitic wasps of the subfamily Eupelminae (Hymenoptera: Chalcidoidea: Eupelmidae) for subfamily systematics
- Creator:
- Fusu, Lucian
- Type:
- article, model:article, and TEXT
- Subject:
- Karyotype, karyosystematics, parasitic wasps, Chalcidoidea, and Eupelmidae
- Language:
- English
- Description:
- Karyotypes of 16 Eupelminae species were analyzed. The haploid chromosome number was found to be much more diverse than the n = 5 previously recorded for three studied species. All species investigated of Eupelmus (Eupelmus), Eupelmus (Macroneura), Merostenus excavatus and three species of Anastatus have a karyotype of n = 5; n = 7 in Eupelmus (Episolindelia) linearis, n = 8 in Arachnophaga picardi, and n = 10 in Anastatus ruficaudus. The modal chromosome number is n = 5 and this is considered to be the plesiomorphic character state for the subfamily; karyotypes with higher chromosome numbers are hypothesized to be derived independently from the ancestral state by centric fission. This cytogenetical data provides important information on the subfamily systematics, especially the subgeneric classification of Eupelmus and generic placement of Eupelmus rostratus.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public