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Article: Structural Integrity of Steel Pipeline with Clusters of Corrosion Defects.

Witek, Maciej

2021 Volume 14, Issue 4

Abstract: The main goal of this paper is to evaluate the burst pressure and structural integrity of a steel pipeline based on in-line inspection results, in respect to the grouping criteria of closely spaced volumetric surface features. In the study, special ... ...

Abstract	The main goal of this paper is to evaluate the burst pressure and structural integrity of a steel pipeline based on in-line inspection results, in respect to the grouping criteria of closely spaced volumetric surface features. In the study, special attention is paid to evaluation of data provided from the diagnostics using an axial excitation magnetic flux leakage technology in respect to multiple defects grouping. Standardized clustering rules were applied to the corrosion pits taken from an in-line inspection of the gas transmission pipeline. Basic rules of interaction of pipe wall metal losses are expressed in terms of longitudinal and circumferential spacing of the features in the colony. The effect of interactions of the detected anomalies on the tube residual strength evaluated according to the Det Norske Veritas Recommended practice was investigated in the current study. In the presented case, groups of closely-spaced defects behaved similarly as individual flaws with regard to their influence on burst pressure and pipeline failure probability.
Language	English
Publishing date	2021-02-10
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2487261-1
ISSN	1996-1944
ISSN	1996-1944
DOI	10.3390/ma14040852
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Conference proceedings ; Online: Understanding sub-lithospheric upper mantle anisotropy beneath the oceans with seismology and geodynamics

Ferreira, A. / Kendall, E. / Manuele, F. / Chang, S. / Witek, M.

XXVIII General Assembly of the International Union of Geodesy and Geophysics (IUGG)

2023

Abstract: While the presence of anisotropy in the uppermost mantle is well established, its detailed patterns are still debated. We present SPacific-rani, a new upper mantle radially anisotropic model of the Pacific which builds on the global whole mantle radially ...

Abstract	While the presence of anisotropy in the uppermost mantle is well established, its detailed patterns are still debated. We present SPacific-rani, a new upper mantle radially anisotropic model of the Pacific which builds on the global whole mantle radially anisotropic model SGLOBE-rani by including additional data along with improved waveform modelling based on the spectral element method. SPacific-rani shows an asymmetry at the East Pacific Rise, requiring stronger radial anisotropy to the West of the East Pacific Rise than to the East, which is possibly due to lattice preferred orientation produced by shear-driven asthenospheric flow beneath the South Pacific superswell. Moreover, SPacific-rani shows a reduction in radial anisotropy with lithospheric age, possibly due to a deviation from horizontal flow as the mantle is entrained with slabs. In order to interpret existing models of upper mantle anisotropy beneath the oceans we develop 2D ridge flow models combined with mantle fabric calculations. We find that faster plates generate higher tectonics stresses and strain rates which lower the dislocation creep viscosity and lead to deeper anisotropy than beneath slower plates. By applying a tomographic filter to the geodynamical models, we retrieve a flat depth-age trend and stronger anisotropy beneath faster plates, which correlates well with existing 3D global anisotropic mantle models. Our predictions and observations suggest that as plate speed increases from 2 to 8 cm/yr, radial anisotropy increases by ∼0.01–0.025 in the upper 100–200 km of the mantle between 10 and 60 Ma.
Subject code	550
Language	English
Publishing country	de
Document type	Conference proceedings ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: The Pattern of Social Parasitism in

Witek, Magdalena / La Morgia, Valentina / Casacci, Luca Pietro / Barbero, Francesca

Insects

2023 Volume 14, Issue 2

Abstract: The parasitic relationship ... ...

Abstract	The parasitic relationship between
Language	English
Publishing date	2023-02-12
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2662247-6
ISSN	2075-4450
ISSN	2075-4450
DOI	10.3390/insects14020180
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Article ; Online: The effect of biopolymer-water interaction on relaxation phenomena in blackcurrant pectin solutions.

Pancerz, Michał / Kruk, Joanna / Witek, Magdalena / Ptaszek, Anna

Food chemistry

2022 Volume 383, Page(s) 132600

Abstract: Pectin is commonly used food additive. Depends on the source of the acquisition, its properties may vary significantly, therefore pectin obtained from different sources may be used for various purposes. Little information can be found about the ... ...

Abstract	Pectin is commonly used food additive. Depends on the source of the acquisition, its properties may vary significantly, therefore pectin obtained from different sources may be used for various purposes. Little information can be found about the properties of blackcurrant pectin. Therefore, the aim of this study was to investigate blackcurrant pectin properties, with particular emphasis on biopolymer behaviour in aqueous solutions. Applied water extraction resulted in a water-soluble fraction of pectin with M
MeSH term(s)	Pectins/chemistry ; Polysaccharides ; Ribes ; Solutions ; Viscosity ; Water/analysis
Chemical Substances	Polysaccharides ; Solutions ; Water (059QF0KO0R) ; Pectins (89NA02M4RX)
Language	English
Publishing date	2022-03-04
Publishing country	England
Document type	Journal Article
ZDB-ID	243123-3
ISSN	1873-7072 ; 0308-8146
ISSN (online)	1873-7072
ISSN	0308-8146
DOI	10.1016/j.foodchem.2022.132600
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Article ; Online: Urban abiotic stressors drive changes in the foraging activity and colony growth of the black garden ant Lasius niger.

Trigos-Peral, G / Maák, I E / Schmid, S / Chudzik, P / Czaczkes, T J / Witek, M / Casacci, L P / Sánchez-García, D / Lőrincz, Á / Kochanowski, M / Heinze, J

The Science of the total environment

2024 Volume 915, Page(s) 170157

Abstract: Changes in habitat characteristics are known to have profound effects on biotic communities and their functional traits. In the context of an urban-rural gradient, urbanisation drastically alters abiotic characteristics, e.g., by increasing environmental ...

Abstract	Changes in habitat characteristics are known to have profound effects on biotic communities and their functional traits. In the context of an urban-rural gradient, urbanisation drastically alters abiotic characteristics, e.g., by increasing environmental temperatures and through light pollution. These abiotic changes significantly impact the functional traits of organisms, particularly insects. Furthermore, changes in habitat characteristics also drive changes in the behavioural traits of animals, allowing them to adapt and thrive in new environments. In our study, we focused on the synanthropic ant species Lasius niger as a model organism. We conducted nocturnal field observations and complemented them with laboratory experiments to investigate the influence of night warming (NW) associated with Urban Heat Islands (UHI), light pollution (ALAN), and habitat type on ant foraging behaviour. In addition, we investigated the influence of elevated temperatures on brood development and worker mortality. Our findings revealed that urban populations of L. niger were generally more active during the night compared to their rural counterparts, although the magnitude of this difference varied with specific city characteristics. In laboratory settings, higher temperatures and continuous illumination were associated with increased activity level in ants, again differing between urban and rural populations. Rural ants exhibited more locomotion compared to their urban counterparts when maintained under identical conditions, which might enable them to forage more effectively in a potentially more challenging environment. High temperatures decreased the developmental time of brood from both habitat types and increased worker mortality, although rural colonies were more strongly affected. Overall, our study provides novel insights into the influence of urban environmental stressors on the foraging activity pattern and colony development of ants. Such stressors can be important for the establishment and spread of synanthropic ant species, including invasive ones, and the biotic homogenization of anthropogenic ecosystems.
MeSH term(s)	Animals ; Ecosystem ; Ants ; Cities ; Niger ; Hot Temperature
Language	English
Publishing date	2024-01-18
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	121506-1
ISSN	1879-1026 ; 0048-9697
ISSN (online)	1879-1026
ISSN	0048-9697
DOI	10.1016/j.scitotenv.2024.170157
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Article: Radial Anisotropy in East Asia From Multimode Surface Wave Tomography

Witek, M. / Chang, S.‐J. / Lim, D. Y. / Ning, S. / Ning, J.

Journal of geophysical research. 2021 July, v. 126, no. 7

2021

Abstract: We present a model of radial anisotropy in the crust and upper mantle of East Asia from a combination of new group velocity measurements and previously published surface wave dispersion data sets. Our combined data set ranges 5–375 s period and contains ... ...

Abstract	We present a model of radial anisotropy in the crust and upper mantle of East Asia from a combination of new group velocity measurements and previously published surface wave dispersion data sets. Our combined data set ranges 5–375 s period and contains dispersion data up to the fifth overtone. We directly relate the data to variations in isotropic and radially anisotropic shear wave crustal and mantle structure via surface wave ray theory applied to a prior 3‐D reference model. Our isotropic S‐velocity model shares high correlations with previous studies, including a model derived from a full waveform inversion methodology. The short period dispersion measurements in our data set allow us to resolve crustal structure without the need for crustal corrections, and as a result, our radial anisotropy model has significant differences with previous studies. We find strong positive radial anisotropy (ξ > 1) across the entire region in the middle to lower crust and uppermost mantle. We perform a cluster analysis and find high levels of radial anisotropy (ξ > 1.12) in the lithospheric mantle of the back‐arc basin and in collisional belts, while low levels of radial anisotropy (ξ ∼ 1.04) are found in the mantle wedge of NE Japan and in the mantle upwelling under Mt. Baekdu. High radial anisotropy is found in the lower crust in regions that experienced continental rifting and lithospheric thinning, while the lowest crustal radial anisotropy is found in stable cratons.
Keywords	Japan ; anisotropy ; basins ; cluster analysis ; data collection ; geophysics ; isotropy ; models ; research ; tomography
Language	English
Dates of publication	2021-07
Publishing place	John Wiley & Sons, Ltd
Document type	Article
Note	JOURNAL ARTICLE
ISSN	2169-9313
DOI	10.1029/2020JB021201
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Infection with a non-lethal fungal parasite is associated with increased immune investment in the ant Myrmica scabrinodis.

Orbán-Bakk, Kincső / Witek, Magdalena / Dubiec, Anna / Heinze, Jürgen / Markó, Bálint / Csata, Enikő

Journal of invertebrate pathology

2023 Volume 202, Page(s) 108027

Abstract: Social insects, such as ants, are preferred host organisms of pathogens and parasites because colonies are densely populated, and the number of potential hosts is high in the same place and time. Within a colony, individuals are exposed differentially to ...

Abstract	Social insects, such as ants, are preferred host organisms of pathogens and parasites because colonies are densely populated, and the number of potential hosts is high in the same place and time. Within a colony, individuals are exposed differentially to risks according to their function and age. Thus, older individuals forage and are therefore the most exposed to infection, predation, or physical stress, while young workers mostly stay inside the sheltered nest being less exposed. Immune investment is considered to be dependent on an individual's age and pathogen pressure. Long-term exposure to a parasite could affect the immune activity of individuals in an intriguing way that interferes with the age-dependent decline in immunocompetence. However, there are only few cases in which such interferences can be studied. The myrmecopathogenic fungus Rickia wasmannii, which infects entire colonies without killing the workers, is a suitable candidate for such studies. We investigated the general immunocompetence of Myrmica scabrinodis ant workers associated with non-lethal fungal infection by measuring the levels of active phenoloxidase (PO) and total PO (PPO) (reflecting the amount of both active and inactive forms of the enzyme) in two age classes. The level of PO proved to be higher in infected workers than in uninfected ones, while the level of PPO increased with age but was not affected by infection. Overall, these results indicate that a long-term infection could go hand in hand with increased immune activity of ant workers, conferring them higher level of protection.
MeSH term(s)	Animals ; Parasites ; Ants/microbiology ; Mycoses ; Predatory Behavior ; Stress, Physiological
Language	English
Publishing date	2023-11-30
Publishing country	United States
Document type	Journal Article
ZDB-ID	390885-9
ISSN	1096-0805 ; 0022-2011
ISSN (online)	1096-0805
ISSN	0022-2011
DOI	10.1016/j.jip.2023.108027
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Article ; Online: Glass Transition in Rice Pasta as Observed by Combined Neutron Scattering and Time-Domain NMR.

Witek, Magdalena / Krzystyniak, Maciej / Romanelli, Giovanni / Witczak, Teresa

Polymers

2021 Volume 13, Issue 15

Abstract: Experimental protocols aiming at the characterisation of glass transition often suffer from ambiguity. The ambition of the present study is to describe the glass transition in a complex, micro heterogeneous system, the dry rice pasta, in a most ... ...

Abstract	Experimental protocols aiming at the characterisation of glass transition often suffer from ambiguity. The ambition of the present study is to describe the glass transition in a complex, micro heterogeneous system, the dry rice pasta, in a most unambiguous manner, minimising the influence of technique-specific bias. To this end, we apply an unprecedented combination of experimental techniques. Apart from the usually used NMR and DSC, we employ, in a concurrent manner, neutron transmission, diffraction, and Compton scattering. This enables us to investigate the glass transition over a range of spatio-temporal scales that stretches over seven orders of magnitude. The results obtained by neutron diffraction and DSC reveal that dry rice pasta is almost entirely amorphous. Moreover, the glass transition is evidenced by neutron transmission and diffraction data and manifested as a significant decrease of the average sample number density in the temperature range between 40 and 60 °C. At the microscopic level, our NMR, neutron transmission and Compton scattering results provide evidence of changes in the secondary structure of the starch within the dry rice pasta accompanying the glass transition, whereby the long-range order provided by the polymer structure within the starch present in the dry rice pasta is partially lost.
Language	English
Publishing date	2021-07-23
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2527146-5
ISSN	2073-4360 ; 2073-4360
ISSN (online)	2073-4360
ISSN	2073-4360
DOI	10.3390/polym13152426
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Article: Analytical Model and Numerical Analysis of Composite Wrap System Applied to Steel Pipeline.

Djahida, Djouadi / Tewfik, Ghomari / Witek, Maciej / Abdelghani, Mechri

Materials (Basel, Switzerland)

2021 Volume 14, Issue 21

Abstract: Composite overwraps are a cost-effective repair technology, appropriate for corrosion defects, dents, and gouges for both onshore and offshore steel pipelines. The main benefit of polymer-based sleeves is safe installation without taking the pipeline out ...

Abstract	Composite overwraps are a cost-effective repair technology, appropriate for corrosion defects, dents, and gouges for both onshore and offshore steel pipelines. The main benefit of polymer-based sleeves is safe installation without taking the pipeline out of service. This paper presents a new calculation procedure proposed in the form of an algorithm for the sizing of composite repairs of corroded pipelines when the sleeve is applied at zero internal pressure. The main objective of the presented methodology is determination of the effective thickness of the composite repair without its overestimation or underestimation. The authors used a non-linear finite element method with constitutive models allowing analysis of the steel, putty, and composite structures. The validation of the results of numerical computations compared to the experimental ones showed an appropriate agreement. The numerical calculations were applied to compare the analytical results in relation to those obtained by the standards ASME PCC-2 or ISO/TS 24817. The comparison showed that the proposed solution confirmed its effectiveness in reducing the thickness of the sleeve significantly, thus, showing that the current industrial standards provide a considerably excessive composite wrap around the steel pipe corroded area, which leads to an unnecessary increase in the repair costs.
Language	English
Publishing date	2021-10-25
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2487261-1
ISSN	1996-1944
ISSN	1996-1944
DOI	10.3390/ma14216393
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Article: Factors of Stress Concentration around Spherical Cavity Embedded in Cylinder Subjected to Internal Pressure.

Abdelghani, Mechri / Tewfik, Ghomari / Witek, Maciej / Djahida, Djouadi

Materials (Basel, Switzerland)

2021 Volume 14, Issue 11

Abstract: In this paper, an accurate distribution of stress as well as corresponding factors of stress concentration determination around a spherical cavity, which is considered as embedded in a cylinder exposed to the internal pressure only, is presented. This ... ...

Abstract	In this paper, an accurate distribution of stress as well as corresponding factors of stress concentration determination around a spherical cavity, which is considered as embedded in a cylinder exposed to the internal pressure only, is presented. This approach was applied at three main meridians of the porosity by combining the Eshelby's equivalent inclusion method with Mura and Chang's methodology employing the jump condition across the interface of the cavity and matrix, respectively. The distribution of stresses around the spherical flaw and their concentration factors were formulated in the form of newly formulated analytical relations involving the geometric ratio of the cylinder, such as external radius and thickness, the angle around the cavity, depth of the porosity, as well as the material Poisson ratio. Subsequently, a comparison of the analytical results and the numerical simulation results is applied to validate obtained results. The results show that the stress concentration factors (SCFs) are not constant for an incorporated flaw and vary with both the porosity depth and the Poisson ratio, regardless of whether the cylinder geometric ratio is thin or thick.
Language	English
Publishing date	2021-06-03
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2487261-1
ISSN	1996-1944
ISSN	1996-1944
DOI	10.3390/ma14113057
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