scholarly journals Lake sedimentary biogenic silica from diatoms constitutes a significant global sink for aluminium

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Dong Liu ◽  
Peng Yuan ◽  
Qian Tian ◽  
Hongchang Liu ◽  
Liangliang Deng ◽  
...  
Keyword(s):  
Biogenic Silica ◽  
Biogeochemical Cycle ◽  
Biochemical Processes ◽  
Al Content ◽  
High Al Content ◽  
Global Oceans

Abstract Diatoms play an important role in marine biogeochemical cycle of aluminum (Al), as dissolved Al is taken up by diatoms to build their siliceous frustules and is involved in the sedimentation of diatomaceous biogenic silica (BSi). The Al incorporation in BSi facilitates decreasing the dissolution of marine BSi and thus substantially influences the biochemical processes driven by diatoms, such as CO2 sequestration. However, the role of lake BSi in the terrestrial biochemical Al cycle has not been explored, though lakes represent the second-largest sink for BSi. By identifying the previously unexplored high Al/Si atomic ratios (up to 0.052) in lake BSi, here we show lake BSi is a large terrestrial Al pool due to its high Al content, and lake sedimentary BSi constitutes a significant global sink for Al, which is on the same magnitude as the Al sink in global oceans.

APPLICATION OF PIXE IN MEDICAL STUDY: ENVIRONMENTAL MINERALS AND NEURODEGENERATIVE DISORDERS

1999 ◽  
Vol 09 (03n04) ◽  
pp. 245-257 ◽  
Author(s):  
S. Yoshida
Keyword(s):  
Hippocampal Neurons ◽  
Green Fluorescence ◽  
Kii Peninsula ◽  
Al Content ◽  
Medical Study ◽  
Environmental Status ◽  
Alzheimer's Neurofibrillary Tangles ◽  
High Al Content ◽  
Lateral Sclerosis

Comparative study on amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia (PDC) in the Kii Peninsula of Japan and Guam was conducted to evaluate the participatory role of environmental minerals in the pathogenesis of the above neurodegenerative diseases, using particle-induced x-ray emission (PIXE) spectrometry and morphometric-statistical analysis. A significantly high content of Al in the hippocampus and spinal cord of Kii and Guamanian ALS/PD cases was found with a positive correlation for Fe and Cu , and a negative correlation for Zn . The numbers of hippocampal neurons in Guamanian PDC, Alzheimer's disease, and Parkinson's disease were significantly decreased with a high Al content. Al content significantly and positively correlated with the number of Alzheimer's neurofibrillary tangles (NFTs) in the hippocampus of ALS cases and controls in both foci, especially in Guamanian cases. The slope of best linear regression of Guamanian cases was markedly steeper than that of Japanese cases ( p < 0.001). Morin staining for Al showed green fluorescence on the nucleolus, cytoplasm, and NFT in the hippocampus of Kii ALS cases. These findings suggest that Guamanian and Kii people have a predisposition to develop ALS/PDC precipitated by their geological/geochemical environmental status, i.e., a prolonged low intake of Ca and Mg together with excess exposure to Al and other environmental minerals.

Microbial Biofilms and Biotechnology – Some Perceptions

2020 ◽  
Vol 09 ◽  
Author(s):  
Subba Rao Toleti
Keyword(s):  
Tissue Culture ◽  
Synthetic Biology ◽  
Industrial Effluents ◽  
Aquatic Environments ◽  
Biochemical Processes ◽  
Microbial Biofilms ◽  
Biofilm Bacteria ◽  
Prophylactic Vaccines ◽  
Design Construction

: The review is an attempt to introduce the readers in brief about biofilms and their implications as well as some new perceptions in biotechnology. Biofilms are adherent microbial communities, which are developed on submerged surfaces in aquatic environments. Biofilms play a significant role in exopolymer production, material deterioration and also cause harmful infections. Further, the role of corrosion causing biofilm bacteria in deterioration of different materials, microbial biofilms and their enzymatic processes in reducing the toxicity of pollutants in industrial effluents are elaborated, along with clean technologies for wastewater treatment. Biotechnology is defined as any technological application that uses biological systems to synthesize or modify products or processes. The applications include biochemical processes, medical care, cell and tissue culture as well as synthetic biology and others. Synthetic biology details about the design, construction of new biological components and systems for useful purposes. Finally, to overcome the limitations that are inherent to the use of cellular host’s, cell-free systems as critical platforms for synthetic biology applications. This mini-review also mentions about new diagnostic products based on enzymes, monoclonal antibodies and engineered proteins as well as novel prophylactic vaccines.

The role of plastic debris in the biogeochemical cycle of mercury in Lake Erie and San Francisco Bay

2021 ◽  
Vol 171 ◽  
pp. 112768
Author(s):  
Katlin L. Bowman ◽  
Carl H. Lamborg ◽  
Alison M. Agather ◽  
Chad R. Hammerschmidt
Keyword(s):  
San Francisco ◽  
Lake Erie ◽  
San Francisco Bay ◽  
Biogeochemical Cycle ◽  
Plastic Debris

scholarly journals Silicon cycle in the tropical South Pacific: contribution to the global Si cycle and evidence for an active pico-sized siliceous plankton

2018 ◽  
Vol 15 (18) ◽  
pp. 5595-5620 ◽  
Author(s):  
Karine Leblanc ◽  
Véronique Cornet ◽  
Peggy Rimmelin-Maury ◽  
Olivier Grosso ◽  
Sandra Hélias-Nunige ◽  
...  
Keyword(s):  
Community Structure ◽  
Chlorophyll A ◽  
Biogenic Silica ◽  
New Caledonia ◽  
Size Fraction ◽  
South Pacific ◽  
Size Class ◽  
Biogeochemical Cycle ◽  
Standing Stocks ◽  
Negligible Contribution

Abstract. This article presents data regarding the Si biogeochemical cycle during two oceanographic cruises conducted in the tropical South Pacific (BIOSOPE and OUTPACE cruises) in 2005 and 2015. It involves the first Si stock measurements in this understudied region, encompassing various oceanic systems from New Caledonia to the Chilean upwelling between 8 and 34∘ S. Some of the lowest levels of biogenic silica standing stocks ever measured were found in this area, notably in the southern Pacific gyre, where Chlorophyll a concentrations are the most depleted worldwide. Integrated biogenic silica stocks are as low as 1.08±0.95 mmol m−2 and are the lowest stocks measured in the South Pacific. Size-fractionated biogenic silica concentrations revealed a non-negligible contribution of the pico-sized fraction (<2–3 µm) to biogenic silica standing stocks, representing 26%±12% of total biogenic silica during the OUTPACE cruise and 11%±9% during the BIOSOPE cruise. These results indicate significant accumulation in this size class, which was undocumented for 2005, but has since then been related to Si uptake by Synechococcus cells. Si uptake measurements carried out during BIOSOPE confirmed biological Si uptake by this size fraction. We further present diatoms community structure associated with the stock measurements for a global overview of the Si cycle in the tropical South Pacific.

Dielectric properties of anodized Al-Ta alloy films with high Al content

1975 ◽  
Vol 27 (1) ◽  
pp. 111-121 ◽  
Author(s):  
A. Schauer ◽  
M. Roschy ◽  
W. Juergens
Keyword(s):  
Dielectric Properties ◽  
Alloy Films ◽  
Al Content ◽  
High Al Content

scholarly journals Epigenetic Approach to PTSD: In the Aspects of Rat Models

2021 ◽  
Author(s):  
Asli Aykac ◽  
Rasime Kalkan
Keyword(s):  
Risk Factors ◽  
Environmental Factors ◽  
Animal Studies ◽  
Stress Disorder ◽  
Biological Response ◽  
Traumatic Experiences ◽  
Biochemical Processes ◽  
Life Threatening ◽  
Shed Light

AbstractPosttraumatic stress disorder (PTSD) is a stress-related mental disorder and develops after exposure to life-threatening traumatic experiences. The risk factors of PTSD included genetic factors; alterations in hypothalamic–pituitary–adrenal (HPA) axis; neurotrophic, serotonergic, dopaminergic, and catecholaminergic systems; and a variety of environmental factors, such as war, accident, natural disaster, pandemic, physical, or sexual abuse, that cause stress or trauma in individuals. To be able to understand the molecular background of PTSD, rodent animal models are widely used by researchers. When looking for a solution for PTSD, it is important to consider preexisting genetic risk factors and physiological, molecular, and biochemical processes caused by trauma that may cause susceptibility to this disorder. In studies, it is reported that epigenetic mechanisms play important roles in the biological response affected by environmental factors, as well as the task of programming cell identity. In this article, we provided an overview of the role of epigenetic modifications in understanding the biology of PTSD. We also summarized the data from animal studies and their importance during the investigation of PTSD. This study shed light on the epigenetic background of stress and PTSD.

Early onset of puberty in cattle: implications for gamete quality and embryo survival

2018 ◽  
Vol 30 (1) ◽  
pp. 101 ◽  
Author(s):  
D. A. Kenny ◽  
J. Heslin ◽  
C. J. Byrne
Keyword(s):  
Sexual Maturation ◽  
Production Systems ◽  
Nutritional Management ◽  
Embryo Survival ◽  
Biochemical Processes ◽  
Overwhelming Evidence ◽  
Subsequent Fertility ◽  
Timing Of Puberty ◽  
Female Cattle

Advancing the age at which puberty and subsequent sexual maturation is attained in cattle is central to the reproductive and economic efficiency of both beef and dairy production systems worldwide. Onset of puberty in both male and female cattle is regulated by a complex network of biochemical processes and involves interaction among many key metabolic, neuroendocrine and reproductive tissues. Although our understanding of the biochemical interplay that conditions and eventually triggers the pubertal process has improved in recent years, much of the intricate mechanistic detail still eludes us. Environmental factors, such as nutritional management, as well as the genetic makeup of the animal undoubtedly affect the timing of puberty in cattle. In particular, there is now overwhelming evidence to support the importance of early life nutrition in regulating the timing of puberty in both bulls and heifers. For both genders, there is significant evidence that an improved metabolic status, early in calfhood, advances maturation of the hypothalamic–pituitary–gonadal axis, therefore facilitating earlier sexual development. Although advancing sexual maturation is a desirable goal, it is important that any strategy used does not impinge upon normal gametogenesis or postpubertal fertility potential. To this end, the aim of this review is to discuss the underlying biology of puberty in cattle with particular emphasis on the role of nutritional management during early calfhood in: (1) advancing the maturity of the hypothalamic–pituitary–gonadal axis; and (2) implications for the quality of gametes and subsequent fertility.

Biological Role of Magnesium

1958 ◽  
Vol 4 (6) ◽  
pp. 429-451 ◽  
Author(s):  
A La Pleshchitser
Keyword(s):  
Atmospheric Oxygen ◽  
Biological Significance ◽  
Biological Role ◽  
Living Matter ◽  
Antagonistic Action ◽  
Biochemical Processes ◽  
The Central Nervous System ◽  
The Stability ◽  
Labile Equilibrium

Abstract Fersman (1934) commented on the relatively unimportant role of magnesium in biochemical processes. The comparatively limited radius of its ions, the stability and relative insolubility of its compounds prevent its taking an active part in the reactions of living matter. On the other hand, we have the statement of Vernadskii that in the plankton film of the ocean, in the ordinary accumulations and more massive growths, the amount of magnesium-containing chlorophyll must reach the order of 10-4 per cent by weight, if not higher, so that a small quantity of magnesium, entering into the composition of the chlorophyll-complex of the plankton, ultimately regulates the main part of the oxygenating function of living matter, the creation of free atmospheric oxygen. The material summarized by us likewise affords evidence of the importance of the role of magnesium in biological processes. All this, however, does not justify sharp differentiation between the biological role of magnesium and its role in biochemical processes. In all probability these processes are conditional to each other, although they are not identical processes. It is important to note the established and incontestable role of magnesium in many enzymatic processes in both the plant and animal kingdoms. The antagonistic action between magnesium and calcium, resulting from artificial changes in the ratios of these elements in soil, plants, and animals, can hardly occur under natural conditions, and, conversely, it must be assumed that a labile equilibrium between these elements is always maintained. The depressing action of magnesium ions on the central nervous system acquires considerable biological significance, since this permits the assumption that these ions in the animal organism may facilitate inhibitory processes in the nerve cell and insure the normal course of catabolic and anabolic processes. The narcotic and cholinolytic effects of magnesium constitute the basis for the wide therapeutic use of magnesium salts in medical practice.

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