Wyniki wyszukiwania

Filtruj wyniki

  • Czasopisma
  • Autorzy
  • Słowa kluczowe
  • Data
  • Typ

Wyniki wyszukiwania

Wyników: 6
Wyników na stronie: 25 50 75
Sortuj wg:

Abstrakt

Progesterone (P4) is responsible for the main reproduction processes. Concentration of P4 varies widely among different determination methods, and interpretation of these values may be difficult. The objective of the current study was to assess the agreement of three different enzyme immunoassays (ELISA) in relation to radioimmunoassay (RIA) of P4 concentration assessment of beef cow serum samples. Samples were collected randomly considering high (pregnant cows) and low (non-pregnant cows) P4 concentrations. Depending on the P4 assessment method, four groups were created as follows: Group 1 – direct samples assessed by ELISA, Group 2 – extracted samples assessed by ELISA, Group 3 – samples assessed by automated ELISA, and Group 4 – samples assessed by RIA.

The mean progesterone concentration was 4.50 ng/mL, 1.24 ng/mL, 4.07 ng/mL and 4.39 ng/mL from Group 1 to Group 4, respectively. The mean difference (MD) between Group 1, Group 2 and Group 3 individually compared with Group 4 was −0.10 ± 1.24 ng/mL, 3.15 ± 3.58 ng/mL and 0.33 ± 1.42 ng/mL, and the 95% confidence interval (CI) for the differences (s) was from −0.99 to 0.78 ng/mL, from 0.59 to 5.71 ng/mL, and from −0.69 to 1.34 ng/mL, respectively. The confidence interval for the lower and upper limit of the agreement ranged from −4.12 to −1.05 ng/mL and from 0.84 to 3.91 ng/mL between Group 1 and Group 4, from −8.45 to 0.42 ng/ mL and from 5.88 to 14.75 ng/mL between Group 2 and Group 4, from −4.29 to −0.76 ng/mL, and from 1.41 to 4.94 ng/mL between Group 3 and Group 4.

Our findings show that the best agreement with RIA was observed for Group 1 and Group 3, while the agreement in the extraction method was least accurate.

Przejdź do artykułu

Autorzy i Afiliacje

A. Rekešiūtė
A. Januškauskas
A. Šiukščius
V. Riškevičienė
A. Vitkauskienė
R. Verkauskienė
R. Antanaitis
H. Žilinskas

Abstrakt

The article presents the methodology for selecting the optimal variant of the road on a regional level. The suggested methodology is based on a combination of criteria value normalization method and the variant assessment method. Based on survey studies conducted using the Delphi method, a starting list of criteria was designed and the significance of the individual groups of main criteria and sub-criteria was determined. The final assessments of the analysed variants are calculated based on the aggregation of the marks obtained for the normalization and assessment methods. The methodology can be divided into six stages: determining the variants for analysis, selecting the variant assessment criteria, creating the assessment matrix, normalizing criteria value, using the variant assessment method, variant ranking. The methodology was tested on the examples of planning a bypass of Mazury and Księżyno towns as a part of Regional Road 678 in Poland.

Przejdź do artykułu

Autorzy i Afiliacje

P. Żabicki
W. Gardziejczyk

Abstrakt

Groundwater is a vital resource for domestic, agricultural, and industrial activities, as well as for ecosystem services. Despite this, the resource is under significant threat, due to increasing contamination from anthropogenic activities. Therefore, to ensure its reliability for present and future use, effective management of groundwater is important not only in terms of quantity (i.e. abstraction) but also quality. This can be achieved by identifying areas that are more vulnerable to contamination and by implementing protective measures. To identify the risk and delineate areas that are more exposed to pollution, various groundwater vulnerability assessment techniques have been developed across the globe. This paper presents an overview of some of the commonly used groundwater vulnerability assessment models in terms of their unique features and their application. Special emphasis is placed on statistical methods and overlay-index techniques. The assessment of the literature shows that statistical methods are limited in application to the assessment of groundwater vulnerability to pollution because they rely heavily on the availability of sufficient and quality data. However, in areas where extensive monitoring data are available, these methods estimate groundwater vulnerability more realistically in quantitative terms. Many works of research indicate that index-overlay methods are used extensively and frequently in groundwater vulnerability assessments. Due to the qualitative nature of these models, however, they are still subject to modification. This study offers an overview of a selection of relevant groundwater vulnerability assessment techniques under a specificset of hydro-climatic and hydrogeological conditions.
Przejdź do artykułu

Autorzy i Afiliacje

Simeneh Shiferaw Moges
1
ORCID: ORCID
Megersa Olumana Dinka
1
ORCID: ORCID

  1. University of Johannesburg, Faculty of Engineering and the Built Environment, Department of Civil Engineering Sciences, PO Box 524, Auckland Park, 2006 Johannesburg, South Africa

Abstrakt

In accordance with the principles of sustainable construction, the results of Life Cycle Assessment (LCA) technique are useful inputs to the decision-making process when designing a building. This article presents such an analysis of a finished building product, which is a modified concrete mix. The calculations took into account the phases of the A1–A4 cycle, i.e. from the extraction of raw materials to the transport of the finished material to the construction site. Test results for concrete mixes and 28-day solid concrete are presented in tabular form. Based on all the test results obtained, it was found that the addition of waste polypropylene fibres has a positive effect on the key properties for the floor concrete. It has been found that proper processing of banding tapes or other polypropylene waste into macro-fibres can be a good example of proper waste management and can contribute to a significant reduction in residual waste. This additive is emission-free and sourced from recycling, making it an excellent alternative to commonly used dispersed reinforcement.
Przejdź do artykułu

Autorzy i Afiliacje

Anna Starczyk-Kołbyk
1
ORCID: ORCID

  1. Military University of Technology, Faculty of Civil Engineering and Geodesy, ul. gen. SylwestraKaliskiego 2, 00-908 Warsaw, Poland

Abstrakt

Stone arch bridge is an important type in the early bridge construction process because of its beautiful shape, material saving and economic rationality. However, stone material will deteriorate after long-term operation, which results in a decrease in strength and bearing capacity of stone arch bridge. The vehicle load is increasing at the same time. Therefore, accurate evaluation of bearing capacity of stone arch bridge is essential to ensure safety. In this article, a three-span open-spandrel stone arch bridge was taken as research object. Firstly, the bridge damages were investigated and analyzed in detail, and bridge service state was evaluated. Then, based on the evaluation results of disease damages and considering stone material deterioration, a refined finite element model of stone arch bridge was established to analyze bending moment, axial force, strain and deformation. Finally, static load test was carried out to test vertical deformation and stress of arch ring, horizontal displacement of pier, settlement of foundation and development of cracks. The results show that static load test is the most accurate method for evaluating bearing capacity of stone arch bridge. The evaluation accuracy of finite element model based on material correction is in the middle, and the evaluation accuracy of disease damage assessment is the worst. In practical work, bearing capacity of stone arch bridge can be evaluated by combining the three methods with high accuracy and comprehensive results.
Przejdź do artykułu

Autorzy i Afiliacje

Hongshuai Gao
1
ORCID: ORCID
Hourui Duan
1
ORCID: ORCID
Yue Sun
1
ORCID: ORCID
Jiashuo Jian
1
ORCID: ORCID
Jingyuan Zhang
2
ORCID: ORCID
Hongbo Liu
1
ORCID: ORCID

  1. School of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
  2. lnstitute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China

Abstrakt

W artykule dokonano analizy wielokryterialnych metod oceniających budynki zrównoważone i ich wpływ na jakość ekologiczną przestrzeni zbudowanej. Celem jest określenie standardów oceny w wielokryterialnych metodach oraz wykazanie, że obiekty zaprojektowane i wybudowane w zgodzie z ustalonymi standardami i procedurami zwiększają wartości ekologiczne przestrzeni zbudowanej i komfort funkcjonowania mieszkańców. Do analizy wybrano głównie metody cieszące się największym prestiżem wśród użytkowników, planistów, projektantów i inwestorów. Analiza i weryfikacja wybranych metod posłużyła do zaproponowania autorskiego modelu oceny budynków oraz jego weryfikacji w procesie projektowania na przykładzie zaprezentowanych projektów. Wykazano, że analizowane metody oceny budynków korzystnie wpływają na proces projektowania i jakość ekologiczną realizowanej przestrzeni zbudowanej. Poprawa jakości następuje poprzez: proekologiczne użytkowanie terenu, poprawę efektywności energetycznej i efektywności gospodarki wodnej, poprawę efektywności użycia materiałów i surowców, preferowanie materiałów i technologii lokalnych, preferowanie innowacyjności proekologicznej, zwiększenie komfortu użytkowników i mieszkańców oraz ich udział w procesie projektowania i oceny przestrzeni zbudowanej. Celem uzupełniającym jest propagowanie wiedzy z zakresu metodologii projektowania zrównoważonego, w wyniku czego mogą powstawać obiekty architektury proekologicznej wpływające na jakość środowiska mieszkaniowego i komfort funkcjonowania mieszkańców.
Przejdź do artykułu

Autorzy i Afiliacje

Lucjan Wacław Kamionka
1
ORCID: ORCID

  1. Kielce University of Technology Faculty of Civil Engineering and Architecture

Ta strona wykorzystuje pliki 'cookies'. Więcej informacji