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Number of results: 10
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Abstract

The aim of the study was to evaluate the effect of repeated low doses of GnRH agonist buserelin once a day for 5 days on follicle development and ovulation in anovulatory dairy cows with follicles growth only to emergence. The study was conducted on 71 anovulatory Polish Holstein Friesian cows. Anovulation with growth of follicles to emergence was defined as small ovaries with follicles of ≤ 5 mm in diameter and without corpus luteum on two examinations in a 7-10 day interval between 50-60 days after parturition. Cows were allocated to one of two group. Cows from group 1 (n = 58) received 0.4 μg of buserelin (Receptal, MSD, Poland) i.m. once a day for 5 days. Control cows from group 2 (n = 13) received saline. Ovarian structures were monitored weekly after the end of treatment by ultrasound for 4 weeks. The diameter of ovarian follicles on the ovaries was measured and recorded. Occurrence of ovulation was determined by the presence of corpus luteum. Overall, ovulation occurred in 46.6% (27/58) of cows treated with repeated doses of GnRH, while no corpus luteum was observed in the control group during the study period. There were significantly (p<0.05) more follicles 6-9 mm in diameter and 10-20 mm in diameter in cows treated with GnRH than in control cows. In conclusion, repeated low doses of GnRH analogue buserelin once a day for 5 days stimulate the development of ovarian follicles in anovulatory dairy cows with small ovarian follicles and led to ovulation in 46.6% of cows during 4 weeks after the end of the treatment.
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Authors and Affiliations

W. Barański
1
A. Nowicki
1
S. Zduńczyk
1
D. Tobolski
1

  1. Department of Animal Reproduction with Clinic, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 14, 10-719 Olsztyn, Poland
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Abstract

The touch trigger probe plays an important role in modern metrology because of its robust and compact design with crash protection, long life and excellent repeatability. Aside from coordinate measuring machines (CMM), touch trigger probes are used for workpiece location on a machine tool and for the accuracy assessment of the machine tools. As a result, the accuracy of the measurement is a matter of interest to the users. The touch trigger probe itself as well as the measuring surface, the machine tool, measuring environment etc. contribute to measurement inaccuracies. The paper presents the effect of surface irregularities, surface wetness due to cutting fluid and probing direction on probing accuracy on a machine tool.

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Authors and Affiliations

Md. Mizanur Rahman
J.R.R. Mayer
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Abstract

The paper presents research on the capability of the residual magnetic field (RMF) measurement system to be applied to the railway inspection for the early non-destructive detection of defects. The metal magnetic memory (MMM) phenomena are analysed using normal component Hy of self-magnetic flux leakage (SMFL), and its tangential component Hx, as well as their respective gradients. The measurement apparatus is described together with possible factors that may affect the results of measurement. The Type A uncertainty estimation and repeatability tests were performed. The results demonstrate that the system may be successfully applied to detection of head check flaws.

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Authors and Affiliations

Mirosław Rucki
ORCID: ORCID
Anna Gockiewicz
Tadeusz Szumiata
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Abstract

The aim of this study was to evaluate the fertility response of dairy cows with anovulation type I on repeated low doses of GnRH agonist buserelin. The study was conducted on 83 anovulatory and 60 cyclic Polish Holstein Friesian cows. Anovulation type I was defined as small ovaries with follicles of ≤ 5 mm in diameter and without corpus luteum on two examinations in a 7-10 day interval between 50–60 days after parturition. Cows from the experimental group (n=58) received 0.4 μg of buserelin i.m. once a day for 5 consecutive days. Cows from the negative control group (n = 25) received saline. Sixty cyclic cows receiving no treatment served as positive controls. Intervals from calving to estrus and from calving to conception, pregnancy rate 30-35 days and 260 days after AI, and pregnancy loss were calculated. The anovulatory cows had a substantially prolonged calving to conception interval, decreased pregnancy rate and increased pregnancy loss and culling rate compared to cyclic herd mates. The average calving to conception interval was significantly (p<0.05) shorter in treated cows compared to non-treated anovulatory cows (153.7 days vs 209.3 days). In conclusion, repeated low doses of GnRH analogue buserelin led to a significant shortening of calving to conception interval. More clinical trials are needed to determine the practical usefulness of this method for the treatment of anovulation type I in dairy cows.
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Authors and Affiliations

W. Barański
1
A. Nowicki
1
S. Zduńczyk
1
Z. Polak
1

  1. Department of Animal Reproduction with Clinic, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 14, 10-719 Olsztyn, Poland
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Abstract

An enormous number of structures and roads are put on expansive subgrade soils and may be exposed to the swelling and shrinkage risk. To prevent the expanding weight of the subgrade layer under loaded pavement, one of the following strategies may be utilized are geogrid layer. Reinforced pavement layers have been propagated in the field of civil engineering because of their profoundly adaptable and diversified use. In this study, axisymmetric models of pavement layers have been created by 2-D Plaxis software and all of these models included geogrid layers at various positions concentrated to research the impact of geogrid on the critical pavement responses. Geogrid was placed at the bottom of asphalt layer, bottom of base layer, tope and middle of the subgrade layer. All models are loaded with incremental contact pressure between 50 and 600 kPa. Analysis processes have been made for all models and the obtained investigation results show a significant effect on pavement behavior when the a geogrid layer was used under various tire pressures. Also, there is an increase in the bearing capacity of a model that includes geogrid at the top and middle of the subgrade layer by about 35% and the resistance of the asphalt layer to deformation and cracking failure was improved.
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Authors and Affiliations

Ghadah Ghassan Masood
1
ORCID: ORCID
Hadeel Ammar Mohammed
1
ORCID: ORCID
Hanan Adnan Hassan Afaj
1
ORCID: ORCID
Mohammed Yousif Fattah
2
ORCID: ORCID

  1. Lecturer, Highway and Transportation Department, Engineering College, Mustansiriyah University, Iraq, Baghdad
  2. Civil Engineering Department, University of Technology, Iraq
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Abstract

The aim of this study was to evaluate millimeter-scale deformations in Tallinn, the capital of Estonia, by using repeated leveling data and the synthetic aperture radar (SAR) images of Sentinel-1 satellite mission. The persistent scattered interferometric SAR (PS-InSAR) analysis of images from ascending and descending orbits from June 2016 to November 2021 resulted the line-of-sight (LOS) displacement velocities in the Tallinn city center. Velocity solutions were estimated for the full period of time, but also for shorter periods to monitor deformation changes in yearly basis. The gridded LOS velocity models were used for the decomposition of east-west and vertical velocities. Additionally, the uncertainty of 2D velocity solutions was estimated by following the propagation of uncertainty. The 3D velocity of permanent GNSS station “MUS2” in Tallinn was used to unify the reference of all PS-InSAR velocity solutions. The results of the latest leveling in Tallinn city center in 2007/2008 and 2019 showed rather small subsidence rates which were in agreement with InSAR long-termsolution. However, the short-termInSAR velocity solutions revealed larger subsidence of city center with a rate about –10 mm/yr in 2016–2017, and the uplift around 5 mm/yr in 2018–2019 with relatively stable periods in 2017–2018 and 2019–2021. The inclusion of groundwater level observation data and the geological mapping information into the analysis revealed possible spatiotemporal correlation between the InSAR results and the groundwater level variations over the deep valleys buried under quaternary sediments.
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Authors and Affiliations

Tõnis Oja
1
ORCID: ORCID
Anti Gruno
1

  1. Datel AS, Tallinn, Estonia
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Abstract

An outstanding Polish biochemist, laureate of the Foundation for Polish Science Prize in 2007, member of the Polish Academy of Sciences, a head of the Department of Molecular Biomedicine at the Institute of Bioorganic Chemistry, PAS in Poznan

Professor Wlodzimierz Krzyzosiak’s research path led from the structural chemistry of nucleic acids, through molecular genetics and cancer genetics to molecular medicine. In the last years, Professor's scientific activity focused on understanding the role of RNA in the pathogenesis of human neurological diseases caused by the expansion of repetitive sequences. He also developed new methods of experimental therapy for this group of disorders using antisense oligonucleotides and RNA interference technology. He analyzed the factors influencing the microRNA biogenesis and used this knowledge to improve RNA interference technology tools in therapeutic approaches. Overall, Professor Krzyżosiak coauthored more than 130 publications, which have been cited more than 3500 times so far.

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Authors and Affiliations

Marta Olejniczak
Agnieszka Fiszer
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Abstract

In this paper, four full-scale concrete columns with high-strength spiral stirrups (HSSS) are constructed and tested under low-cycle repeated loading. The specimens consisted of two castin- place columns and two precast concrete columns encased by a partly square steel pipe and bolt bars.The structural analysis of the HSSS columns of precast concrete conducted here is novel, and past experimental data for this are not available.To assess the seismic behavior and failure mechanisms of the new connections, quasi-static tests were carried out on columns prefabricated with them and cast-in-place specimens.The responses of all columns were compared, and the results showed that the failure modes of all columns are the large eccentric damage, and the destruction of all specimens occur at the column foot. The anti-seismic property of the precast HSSS concrete columns was comparable to that of the HSSS cast-in-place columns. A comparison of such performance parameters as energy dissipation and coefficient of ductility revealed that the precast HSSS concrete columns are suitable for use in earthquake zones.
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Authors and Affiliations

Zheng Xianchao
1
ORCID: ORCID
Fan Liyun
1
ORCID: ORCID
Jun Zhao
2
ORCID: ORCID

  1. Department of Civil and Architecture Engineering in Hezhou University, Hezhou 542899, China
  2. Department of Civil and Architectural Engineering in Anyang Institute of Technology, Anyang,Henan Province, 455000, China
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Abstract

Lean mixture burning leads to a decrease in the temperature of the combustion process and it is one of the methods of limiting nitric oxide emissions. It also increases engine efficiency. An effective method to correct lean mixture combustion can be a two-stage system of stratified mixture combustion in an engine with a prechamber. This article presents the results of laboratory research on an SI engine (spark ignition) with a two-stage combustion system with a cylinder powered by gasoline and a prechamber powered by propane-butane gas LPG (liquefied petroleum gas). The results were compared to the results of research on a conventional engine with a one-stage combustion process. The test engine fuel mixture stratification method, with a two-stage combustion system in the engine with a prechamber, allowed to burn a lean mixture with an average excess air factor equal to 2.0 and thus led to lower emissions of nitrogen oxides in the exhaust of the engine. The test engine with a conventional, single-stage combustion process allowed to properly burn air-fuel mixtures of excess air factors λ not exceeding 1.5. If the value λ > 1.5, the non-repeatability factor COVLi increases, and the engine efficiency decreases, which makes it virtually impossible for the engine to operate. The engine with a two-stage combustion process, working with λ = 2.0, the Qin/Qtot = 2.5%, reduced the NOx content in the exhaust gases to a level of about 1.14 g/kWh. This value is significantly lower than the value obtained in a conventional engine, which worked at λ = 1.3 with comparable non-repeatability of successive cycles (about 3%) and a similar indicated efficiency (about 34%), was characterised by the emissions of NOx in the exhaust equal to 26.26 g/kWh.

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Authors and Affiliations

Arkadiusz Jamrozik
Wojciech Tutak

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