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1

Delamination analysis in single-point incremental forming of steel/steel bi-layer sheet metal

100%

Hassan M. , Hussain G. , Ilyas M. , Ali A.

Archives of Civil and Mechanical Engineering

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2020

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tom Vol. 20, no. 2

124--137

EN

Layered metallic materials (LMMs) offer superior properties in comparison to their counterpart monolithic sheets. Single-point incremental forming (SPIF) has emerged as an economical solution to produce LMM parts. However, delamination can limit the formability of such parts. In this study, the delamination analysis during SPIF of layered sheets was performed. Steel/steel bi-layer sheets were fabricated by roll bonding. These sheets were produced at thickness reduction ratios of 47%, 58% and 70%. The bond strength and fracture toughness in mode I and mode II were determined by T-peel and tensile shear tests, respectively. When the thickness reduction ratio was increased from 47 to 70%, an increase in bond strength was observed with 572% increase in mode I and 15.6% in mode II, respectively. On the other hand, with the same percent increase in thickness reduction, the critical strain energy release showed an increase of 3992% in mode I and 20% decrease in mode II. Surface-based cohesive zone model was used to define the interface between layers during numerical simulation of SPIF for delamination analysis. To validate the numerical results, SPIF of given bi-layer sheet was performed experimentally and a good agreement between the numerical and experimental results was observed.

2

Benthic foraminifera in eastern bahrain: relationships with local pollution sources

88%

Arslan M. , Kaminski M. A. , Khalil A. , Ilyas M. , Tawabini B. S.

Polish Journal of Environmental Studies

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2017

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tom 26

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nr 3

EN

This preliminary study tracks the response of living benthic foraminifera at a polluted site in eastern Bahrain, with the aim to determine the effects of recent anthropogenic pollution on their distribution patterns and morphological deformities. The boat harbor in Askar, Bahrain is subjected to pollution by nutrients, organic matter, and hydrocarbons. Foraminiferal density is found to be higher at the polluted site compared with a nearby unpolluted site, suggesting a possible higher amount of available nutrients for the benthic foraminifera. Seven taxonomical groups were recognized in the polluted transect, including Ammonia, Glabratellina, Murrayinella, Elphidium, Brizalina, miliolids, and peneroplids. By comparing the foraminiferal assemblages with a nearby unpolluted transect, the genus Murrayinella appeared to be a dominant and pervasive taxon, as it was able to proliferate in the organically polluted environment. The results are contradictory to previously published findings on modern foraminiferal assemblages in the Arabian Gulf, as Murrayinella is rarely reported. However, the population of miliolids was drastically reduced at the polluted site due to high organic matter pollution, which might support the sensitive nature of this taxonomic group. In any case, the miliolids can be considered as a pollution proxy for future biomonitoring studies in the region.

3

The resurgence of measles infection and its associated complications in early childhood at a tertiary care hospital in Peshawar, Pakistan

88%

Ilyas M. , Afzal S. , Ahmad J. , Alghamdi S. , Khurram M.

Polish Journal of Microbiology

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2020

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tom 69

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nr 2

4

Seasonal variations, environmental parameters, and standing crop assessment of benthic foraminifera in eastern Bahrain, Arabian Gulf

75%

Arslan M. , Kaminski M. A. , Tawabini B. S. , Ilyas M. , Babalola L. O. , Frontalini F.

Geological Quarterly

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2016

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tom Vol. 60, No. 1

26--37

EN

Living benthic foraminifera in a relatively unpolluted site offshore Bahrain in the Arabian Gulf, were studied to determine the seasonal variability of their populations, as well as environmental parameters that may affect their distribution. The maximum foraminiferal density was observed during winter with the assemblages primarily dominated by rotaliids and secondarily by miliolids. The high population is attributed to an increased number of juveniles. A relationship between sediment grain size and the foraminiferal density reveals that juveniles were most abundant on coarse-grained sandy substrate and less abundant on fine-grained substrates. In spring, the foraminiferal density decreased, and the lowest values were observed during summer. The population increased again in autumn with highest juvenile/adult ratios. Moreover, results of relative abundance and species consistency show that Ammonia and Glabratellina are consistent from the shallowest to the deepest station, whereas miliolids occurred only at deeper stations. The numbers of peneroplidae and Elphidium also increased along the depth transect. Environmental characterization reveals that although the site is subject to eutrophication caused by nitrates and sulfates, pollution caused by hydrocarbons and heavy metals is not significant. The assessment of 63 heavy metals showed that none of the metals had concentrations that exceed internationally accepted norms [the devised level of Effect Range-Low], but with high concentration of strontium. The lack of a significant environmental effect of heavy metals is confirmed by the Foraminiferal Abnormality Index of <2%. Likewise, no hydrocarbon contamination was detected in the water or sediment samples. We conclude that the site in Bahrain is not yet adversely affected by human development, and therefore can provide baseline information for future comparison and assessment of foraminiferal assemblages in contaminated zones of the Arabian Gulf.

5

Characterization of D-genome diversity for tolerance to boron toxicity in synthetic hexaploid wheat and in silico analysis of candidate genes

75%

Ilyas M. , Mahmood T. , Ali A. , Babar M. , Rasshed A. , Mujeeb-Kazi A.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 02

EN

Boron toxicity is one of the most important environmental stresses prevailing globally, which limits grain production. In wheat, tolerance to boron toxicity has been manipulated around the Bo1 locus on 7BL chromosome. However, there is a need to identify new diversity in other Triticeae to broaden the germplasm base for genetic improvement and greater tolerance durability. Among these resources, Aegilops tauschii (2n = 2x = 14; DD) accessions have demonstrated significant outputs with their contribution of novel alleles for various biotic and abiotic stresses influencing traits that add valueto wheat improvement. This study demonstrates the performance of 45 D-genome synthetic hexaploids wheats (SHWs) derived from a durum cultivar ‘Decoy’ for their tolerance to boron toxicity at seedling plus adult stages and validates their diversity at the molecular level. The root and shoot growth suppression as percentage of control was taken as the selection criteria for boron toxicity tolerance. Analysis of variance (ANOVA) exhibited ample variability (at P = 0.0001) among genotypes, treatments, and their interaction. Among 45 SHWs analyzed, 11 were found tolerant at the seedling stage, while 12 were found tolerant during adult plant screening. The different tolerant accessions at seedling and adult plant revealed that the tolerant mechanism was different at both stages. Genetic diversity was investigated using SSR marker specific to chromosome 7D. A total of 38 alleles were amplified with a mean value of 3.8 alleles per marker. Analysis of molecular variance (AMOVA) further established significant genetic diversity among different clusters. The potential genomic regions underlying tolerance to boron toxicity were also highlighted by searching sequences of cereal boron tolerance genes in wheat-specific databases. The wheat genome survey sequence and the draft genome sequence of Ae. tauschii proved to be useful genomic resources that identified five different chromosomal regions highly similar to the available boron tolerant genes in cereals. Conclusively, tolerance to boron toxicity in SHWs, genetic variability among the tolerant accessions based on SSRs, and availability of orthologous copies of boron tolerance genes make SHWs as potent genetic resources for wheat improvement against boron toxicity.