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2021 ◽  
Vol 9 (10) ◽  
pp. 1150
Author(s):  
Chipeng He ◽  
Longbin Sha ◽  
Dongbo Zhao ◽  
Lu Dai ◽  
Zheng Li ◽  
...  

A new pollen analysis and major and trace element contents were conducted on a 40 m long gravity core recovered from the Taiwan Shoal (sand ridges), south of the Taiwan Strait, beginning in the Late Pleistocene. The changes in the pollen assemblage and concentration represent the climate change around the Taiwan Shoal and the strength of the Zhe-Min Coastal Current, whereas variations in major and trace element contents can imply the source of the sediments in the Taiwan Shoal, which are correlated with the rise or fall of the sea level with increased marine dinoflagellate cysts. The interval of 40–30 m was characterized by high pollen and spore concentrations, and evergreen Quercus was dominant taxon, which indicates a warm sedimentary environment, and the surrounding area of the Taiwan Shoal were covered by a tropical and subtropical broad-leaved forest. There were no pollen and spores from 30–24 m, which indicates a strong hydrodynamic sedimentary environment, and most of the Taiwan Shoal might have been experience subaerial exposure. The interval of 24–17 m was characterized by the reappearance of pollen and spores, as well as marine dinoflagellate cysts and foraminifera, suggesting the climate was warm and wet in the study area and an apparent marine sedimentary environment with relatively high sea level. Deciduous Quercus dominated the interval of 17–12 m, which indicated that the climate was relatively cool, corresponding to the end of Marine isotope stages3 (MIS3) to the Last Glacial Maximum accompanied by weathering and denudation. Above 12 m, the low pollen concentration with increased marine dinoflagellate cysts and foraminifera abundance suggested a marine sedimentary environment in the Taiwan Shoal. The high concentrations in Pinus corresponds to Holocene high sea level.


Author(s):  
Ayşe Semra Aksoy ◽  
Murat Taşan

In this study, it was aimed to determine some element contents and some quality properties and to compare these parameters at each stage in the chemically refining process of crude corn oil. Color (lovibond tintometer), free fatty acidity, peroxide values and fatty acid compositions were determined in the samples of corn oil taken from consecutive stages of chemically refining. Also, the content of elements (Na, Mg, K, Ca, Fe, Pb, Cd, Ni, Mn, Zn, Co, Cr, P, Cu) was analyzed, by using inductively-coupled plasma-mass spectrometry (ICP-MS) and inductively-coupled plasma-optical emission spectrometry (ICP-OES) after microwave digestion. The color (Lovibond tintometer), free fatty acidity and peroxide values in the chemically refining process varied between 2.7-16, %0.09-2.12, 10.95-1.08 mEqO2/kg, respectively. Oleic, linoleic and linolenic acid contents changed between 30.486-30.580%, 54.339-54.703% and 0.972-0.993%, respectively, in the chemically refining stages. While no trans fatty acids detected in crude corn oil and after degumming-neutralization step, very low amount of trans oleic acid (0.040%) and total trans linoleic acid (0.132%) was detected in bleached corn oil. The total trans fatty acid content little more increased in the last stage of the chemically refining. However, total trans fatty acid content of refined corn oil was < 0.3%. It was clearly seen that Na, Mg, K, P, Ca, Mn, Fe, Pb, Ni, Cr, Cu element contents decreased significantly at the end of the chemically refining process. Although Cd, Co and Zn elements were determined in crude corn oil, these elements were not detected in the refined corn oil. The results obtained showed that the chemically refining process effected some of the quality properties of corn oil and especially the changes in the element contents.


Author(s):  
Phuong Truc Huynh ◽  
Binh Thanh Dinh ◽  
Linh Thi Truc Nguyen ◽  
Loan Thi Hong Truong ◽  
Hanh Van Nguyen ◽  
...  

Author(s):  
Qihang Li ◽  
Chaofeng Li ◽  
Shengyang Xiao ◽  
Heng Wang ◽  
Cheng Chen ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Natalia Kurhaluk ◽  
Halyna Tkachenko

AbstractThe aim of our study was to elucidate the effects of both development stages (parr, smolt, adult, spawner), and kelt as a survival form and sex (male, female) on the functional stability of the lysosomal complex, biomarkers of oxidative stress, and element contents in the muscle tissue of the sea trout (Salmo trutta m. trutta L.) sampled in the Pomerania region (northern Poland). We have evaluated the maximal activities of lysosomal enzymes (alanyl aminopeptidase, leucyl aminopeptidase, β-N-acetylglucosaminidase, and acid phosphatase), lipid peroxidation level, and protein carbonyl derivatives as indices of muscle tissue degradation. The relationship between lysosomal activity and oxidative stress biomarkers estimated by the lipid peroxidation level and protein carbonyl derivatives was also assessed, as well as the relationships between element levels and oxidative stress biomarkers. Trends of the main effects (i.e., the development stages and sex alone, the interaction of the sex and development stage simultaneously) on oxidative stress biomarkers, lysosomal functioning, and element contents in the muscle tissue were evaluated. The study has shown sex-related relationships between the pro- and antioxidant balance and the tissue type in the adult stage as well as modifications in the lysosomal functioning induced by long-term environmental stress associated with changing the habitats from freshwater to seawater and intense migrations. The highest level of toxic products generated in oxidative reactions and oxidative modification of proteins was noted in both the spawner stage and the kelt form. The holistic model of analysis of all parameters of antioxidant defense in all development stages and sex demonstrated the following dependencies for the level of lipid peroxidation, oxidative modification of proteins, lysosomal activities, and element contents: TBARS > OMP KD > OMP AD > TAC, AcP > NAG > LAP > AAP and Cu > Fe > Ca > Mn > Zn > Mg, respectively.


2021 ◽  
Author(s):  
Nicholas Udy ◽  
Michael Stearns

&lt;p&gt;The U-Pb system in titanite has been shown to be reset during a variety of high-temperature processes including high-temperature deformation, but post-deformation modification and recovery of crystal-lattice strain have so far made U-Pb equilibration mechanism from deformed titanites equivocal. Microstructures, including mechanical twinning and subgrain rotation recrystallization are more likely to be preserved at low-temperatures, but the systematics of chemical equilibration have not been established for these conditions. This study identifies progressive crystallographic misorientation and deformation twins in titanite porphyroclasts from the Wasatch Fault Zone, Utah, USA. The microstructures, mapped using electron backscatter diffraction (EBSD), developed at ~11 km depth during 300&amp;#8211;400 &amp;#186;C crystal-plastic deformation within the ductile fault zone. These microstructural maps were used to guide laser ablation-split stream ICP-MS analysis: U-Pb isotopes measured in tandem with major and trace element contents. Despite the low temperature, U-Pb and trace element contents in titanite equilibrated, at least partially, during deformation. Both major and trace elements in titanite also likely partitioned with a fluid and in response to the (re)crystallization of other mineral phases in the fault zone. Chemical zoning and crystal lattice recovery suggestive of fluid-aided recrystallization are absent, and the main mechanism for this resetting may instead be an enhancement of element mobility along microstructure dislocations. These processes are interpreted to record complex open-system behavior of titanite caused by crystal-plastic deformation during the initiation of the WFZ. This presentation will summarize the comparative analysis of microstructure by EBSD and titanite chemistry by LASS-ICP-MS, and how it bears on the understanding of elemental mobility in titanite during low-temperature crystal-plastic deformation.&lt;/p&gt;


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