scholarly journals Pyrite Biooxidation by Acidophilic Archaea AcidiplasmaSp. MBA-1 Under Varied Conditions

2022 ◽  
Author(s):  
Aleksandr Bulaev
Keyword(s):  
Potential Role ◽  
Sulfide Mineral ◽  
High Rate ◽  
Mineral Nutrient ◽  
Acidophilic Microorganisms ◽  
Moderately Thermophilic ◽  
Operational Temperature ◽  
Low Levels ◽  
Acidophilic Archaea

The goal of this research was to study pyrite (FeS2 ) bioleaching by a strain of the genus Acidiplasma under different conditions (temperature, pH) to evaluate the potential role of Acidiplasma representatives in biooxidation of this sulfide mineral. To compare the role of Acidiplasma archaea in pyrite biooxidation with other acidophilic microorganisms, the experiments were also performed with representatives of othergroups of microorganisms predominant in biohydrometallurgical processes.Pure and mixed cultures of moderately thermophilic acidophilic microorganisms, including strains Acidithiobacillus caldus MBC-1, Sulfobacillusthermosulfidooxidans VKMV 1269T and Acidiplasmasp. MBA-1, were used. The experiments were carried out in flasks with 100 mL of mineral nutrient medium supplemented with 0.02% yeast extract and 1 g of pyrite on a rotary shaker for 20 days. Bioleaching was performed at 45, 55, and 60∘С. The results demonstrated that the representatives of the genus Acidiplasmaprovided a comparatively higher rate of pyrite bioleaching at high temperatures (55 and 60∘C) and low pH of the medium (1.0). Thus, according to the results, strains of thegenus Acidiplasma may provide a high rate of pyrite bioleaching at low levels ofpH. Therefore, the results suggest that archaea of the genus Acidiplasma may be promising microorganisms to improve bioleaching processes with an increase in the operational temperature, which is usually maintained at 40–45∘C in industrial-scale reactors. Keywords: biomining, bioleaching, acidophilic microorganisms, sulfide minerals, pyrite

Role of uncoupled and non-coupled oxidations in maintenance of safely low levels of oxygen and its one-electron reductants

1996 ◽  
Vol 29 (2) ◽  
pp. 169-202 ◽  
Author(s):  
Vladimir P. Skulachev
Keyword(s):  
Resting State ◽  
Mitochondrial Membrane ◽  
High Rate ◽  
Oxygen Species ◽  
Inner Mitochondrial Membrane ◽  
Enzymatic Formation ◽  
Male Sex ◽  
Low Levels ◽  
Cellular Components

AbstractTo proceed at a high rate, phosphorylating respiration requires ADP to be available. In the resting state, when the energy consumption is low, the ADP concentration decreases so that phosphorylating respiration ceases. This may result in an increase in the intracellular concentrations of O2as well as of one-electron O2reductants such asThese two events should dramatically enhance non-enzymatic formation of reactive oxygen species, i.e. of, and OHׁ, and, hence, the probability of oxidative damage to cellular components. In this paper, a concept is put forward proposing that non-phosphorylating (uncoupled or non-coupled) respiration takes part in maintenance of low levels of both O2and the O2reductants when phosphorylating respiration fails to do this job due to lack of ADP.In particular, it is proposed that some increase in the H+leak of mitochondrial membrane in State 4 lowers, stimulates O2consumption and decreases the level ofwhich otherwise accumulates and serves as one-electron O2reductant. In this connection, the role of natural uncouplers (thyroid hormones), recouplers (male sex hormones and progesterone), non-specific pore in the inner mitochondrial membrane, and apoptosis, as well as of non-coupled electron transfer chains in plants and bacteria will be considered.

scholarly journals Chimeric antigen receptor T cells self-neutralizing IL6 storm in patients with hematologic malignancy

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lei Xue ◽  
Yan Yi ◽  
Qianwen Xu ◽  
Li Wang ◽  
Xiaohui Yang ◽  
...  
Keyword(s):  
Chimeric Antigen Receptor ◽  
Clinical Investigation ◽  
Hematologic Malignancy ◽  
Antigen Receptor ◽  
Complete Response ◽  
High Rate ◽  
Car T ◽  
Life Threatening ◽  
Low Levels

AbstractIL6 is one of the most elevated cytokines during chimeric antigen receptor (CAR) T cell cytokine release syndrome (CRS), and IL6R blockade by Tocilizumab has successfully relieved the most life-threatening aspects of CRS in patients. In addition, latest studies demonstrated the essential role of IL1 in driving CART induced neurotoxicity in mouse models. Here we present a clinical investigation (ChiCTR2000032124; ChiCTR2000031868) of anti-CD19 and anti-BCMA CART (41BBζ) secreting an anti-IL6 scFv and IL1 receptor antagonist (IL1RA) in treating patients with hematologic malignancy. Our results revealed that IL6 and IL1B were maintained at low levels without significant elevation during CRS, rendering Tocilizumab dispensable. Moreover, treated patients did not show neurotoxicity during CRS and exhibited mild to moderate CRS. Notably, we observed high rate of complete response (CR) and significant CART expansion during treatment. In sum, we conclude that CART-secreting anti-IL6 scFv and IL1RA could self-neutralize IL6 storm and maintain low levels of IL1B during CART therapy to minimize IL6- and IL1-associated cytokine toxicity and neurotoxicity without impairing therapeutic efficacy.

Communicating User Experience

2015 ◽  
Vol 7 (2) ◽  
pp. 14-26 ◽  
Author(s):  
Hilary A. Sarat St. Peter
Keyword(s):  
Project Management ◽  
User Experience ◽  
Potential Role ◽  
High Rate ◽  
User Centered Design ◽  
Resource Constrained ◽  
Project Failure ◽  
Ux Design ◽  
User Centered

Research in the ICT4D field implicates lack of user-centered design in the high rate of ICTD project failure. The field of user experience (UX) offers potentially fruitful approaches for user-centered design. In the ICTD context, these principles and methods clash with the triple constraints of project management (time, scope and funding). This paper introduces the user persona from UX design as a powerful tool for considering the user's perspective within resource-constrained ICTD projects. Although personas appear simple, they introduce complex communicative affordances, pragmatic benefits, and risks to ICTD projects. A brief conclusion revisits the larger problem of ICTD project failure, and considers the potential role of personas in addressing this problem.

scholarly journals Potential Role of Thiobacillus caldus in Arsenopyrite Bioleaching

1999 ◽  
Vol 65 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Mark Dopson ◽  
E. Börje Lindström
Keyword(s):  
Mixed Culture ◽  
Pure Culture ◽  
Potential Role ◽  
Mixotrophic Growth ◽  
Moderately Thermophilic ◽  
Surface Active Agents ◽  
Pure Cultures ◽  
Surface Active ◽  
Leaching Efficiency

ABSTRACT We investigated the potential role of the three strains ofThiobacillus caldus (KU, BC13, and C-SH12) in arsenopyrite leaching in combination with a moderately thermophilic iron oxidizer,Sulfobacillus thermosulfidooxidans. Pure cultures ofT. caldus and S. thermosulfidooxidans were used as well as defined mixed cultures. By measuring released iron, tetrathionate, and sulfur concentrations, we found that the presence ofT. caldus KU and BC13 in the defined mixed culture lowered the concentration of sulfur, and levels of tetrathionate were comparable to or lower than those in the presence of S. thermosulfidooxidans. This suggests that T. caldusgrows on the sulfur compounds that build up during leaching, increasing the arsenopyrite-leaching efficiency. This result was similar to leaching arsenopyrite with a pure culture of S. thermosulfidooxidans in the presence of yeast extract. Therefore, three possible roles of T. caldus in the leaching environment can be hypothesized: to remove the buildup of solid sulfur that can cause an inhibitory layer on the surface of the mineral, to aid heterotrophic and mixotrophic growth by the release of organic chemicals, and to solubilize solid sulfur by the production of surface-active agents. The results showed that T. caldus KU was the most efficient at leaching arsenopyrite under the conditions tested, followed by BC13, and finally C-SH12.

scholarly journals Assesssing the role of humans in Greater Antillean land vertebrate extinctions: new insights from Cuba

2020 ◽  
Author(s):  
Johanset Orihuela ◽  
Lázaro W. Viñola ◽  
Osvaldo Jiménez Vázquez ◽  
Alexis M. Mychajliw ◽  
Odlanyer Hernández de Lara ◽  
...  
Keyword(s):  
Potential Role ◽  
Late Quaternary ◽  
Ecological Factors ◽  
High Rate ◽  
Archaeological Record ◽  
Cultural Groups ◽  
Archaeological Data ◽  
The Caribbean ◽  
Land Vertebrate

ABSTRACTThe Caribbean archipelago is a hotspot of biodiversity characterized by a high rate of extinction. Recent studies have examined these losses, but the causes of the Antillean Late Quaternary vertebrate extinctions, and especially the role of humans, are still unclear. Current results provide support for climate-related and human-induced extinctions, but often downplaying other complex bio-ecological factors that are difficult to model or to detect from the fossil and archaeological record. Here, we discuss Caribbean vertebrate extinctions and the potential role of humans derived from new and existing fossil and archaeological data from Cuba. Our results indicate that losses of Cuba’s native fauna occurred in three waves: one during the late Pleistocene and early Holocene, a second during the middle Holocene, and a third one during the last 2 ka, coinciding with the arrival of agroceramists and the early Europeans. The coexistence of now-extinct species with multiple cultural groups in Cuba for over 4 ka implies that Cuban indigenous non-ceramic cultures exerted far fewer extinction pressures to native fauna than the later agroceramists and Europeans that followed. This suggests a determinant value to increased technological sophistication and demographics as the most plausible effective extinction drivers.

Work characteristics and the emergence of a sustainable workforce: Do job design principles matter?

2006 ◽  
Vol 19 (2) ◽  
Author(s):  
Doris Fay ◽  
Alexandra Kamps
Keyword(s):  
Potential Role ◽  
Readiness To Change ◽  
Design Principles ◽  
Job Design ◽  
Work Characteristics ◽  
Work Related ◽  
Personal Initiative ◽  
Low Levels ◽  
Future Work

Work characteristics and the emergence of a sustainable workforce: Do job design principles matter? Work characteristics and the emergence of a sustainable workforce: Do job design principles matter? Doris Fay & Alexandra Kamps, Gedrag & Organisatie, Volume 19, June 2006, nr. 2, pp. 184. Today's organisations require a workforce with high levels of adaptability and flexibility, that is, a sustainable workforce. Drawing on the notion of socialization through work, this study looks at the potential role of job design for building a sustainable workforce. Drawing on data from 335 individuals from the new German countries, we tested whether levels of desirable attitudes and behaviours are associated with the application of Tayloristic design principles. Perceptions of work characteristics (job control, complexity, task completeness, prescription of one-best-way of doing the job) were used to create groups of work places that differed in degree of Taylorism. Comparison of jobs with high versus low levels of Taylorism showed that individuals with Tayloristic jobs had lower work-related self-efficacy, lower personal initiative, innovativity and readiness to change, and higher levels of control rejection and depression than individuals in less Tayloristic jobs. Implications for changing job demands and future work are discussed.

scholarly journals Phytoremediation of Cadmium-, Copper-, and Lead-contaminated Soil by Salix mucronata (Synonym Salix safsaf)

HortScience ◽  
2019 ◽  
Vol 54 (7) ◽  
pp. 1249-1257 ◽  
Author(s):  
El-Sayed Mohamed El-Mahrouk ◽  
Eman Abdel-Hakim Eisa ◽  
Mahmoud Abdelnaby Hegazi ◽  
Mohamed El-Sayed Abdel-Gayed ◽  
Yaser Hassan Dewir ◽  
...  
Keyword(s):  
Contaminated Soil ◽  
Potential Role ◽  
Negative Influence ◽  
Antioxidant Enzyme Activities ◽  
Tolerance Index ◽  
Plant Organs ◽  
Survival Percentage ◽  
Low Levels ◽  
And Control

Phytoremediation is an environmentally friendly and effective method of reducing contaminating ions to very low levels. In this study, the effects of different concentrations of cadmium (Cd), copper (Cu), and lead (Pb) on vegetative growth and the chemical and biochemical compositions of Salix mucronata as well as the potential for phytoextraction of these metals by plant organs were investigated. S. mucronata had the highest survival percentage (100%) in the presence of CdCl2, CuCl2, and Pb acetate up to 80, 200, and 850 mg·kg−1 in soil, respectively. A negative influence of these metals on vegetative and chemical parameters was observed relative to the control plants. The potential role of antioxidant enzymes in protecting plants from oxidative injury was examined by analyzing the antioxidant enzyme activities of plants grown in contaminated and control soils. Enzymatic activities and electrolyte leakage were higher in the plants grown in soil with increasing heavy metals than in the control plants. The bioconcentrating efficiency of Cd, Cu, and Pb in plant organs was estimated to be medium [bioconcentration factor (BCF) of 1–0.1]; an exception was the BCF of Cu in the roots, which was estimated to be intensive (BCF < 1). Concentrations of 60 mg·kg−1 CdCl2, 50 mg·kg−1 CuCl2, and 650 mg·kg−1 Pb acetate caused significantly higher translocation compared with other levels of each pollutant. The biomass tolerance index was less than 1. Additionally, S. mucronata accumulated Cd, Cu, and Pb in the following order: roots > stems > leaves. Therefore, the risk of contamination through leaf fall can be minimized. Therefore, S. mucronata could be a good candidate for phytoremediation of Cd-, Cu-, and Pb-contaminated soil.

scholarly journals Mapping of m6A and Its Regulatory Targets in Prostate Cancer Reveals a METTL3-low Induction of Therapy Resistance

2021 ◽  
Author(s):  
Kellie A. Cotter ◽  
John Gallon ◽  
Nadine Uebersax ◽  
Philip Rubin ◽  
Kate D. Meyer ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Potential Role ◽  
Therapy Resistance ◽  
Gene Signature ◽  
Matrix Proteins ◽  
Hepatocyte Nuclear Factor ◽  
Low Levels ◽  
Post Transcriptional Regulation ◽  
The Relationship

ABSTRACTRecent evidence has highlighted the role of N6-methyladenosine (m6A) in the regulation of mRNA expression, stability and translation, supporting a potential role for post-transcriptional regulation mediated by m6A in cancer. Here we explore prostate cancer as an exemplar and demonstrate that low levels of N6-adenosine-methyltransferase (METTL3) is associated with advanced metastatic disease. To explore this relationship, we generated the first prostate m6A maps, and further examined how METTL3 regulates expression at the level of transcription, translation, and protein. Significantly, transcripts encoding extracellular matrix proteins are consistently upregulated with METTL3 knockdown. We also examined the relationship between METTL3 and androgen signaling and discovered the upregulation of a hepatocyte nuclear factor-driven gene signature that is associated with therapy resistance in prostate cancer. Significantly, METTL3 knockdown rendered the cells resistant to androgen receptor antagonists, implicating changes in m6A as a mechanism for therapy resistance in metastatic prostate cancer.

POPDC proteins and cardiac function

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand
Keyword(s):  
Potential Role ◽  
Striated Muscle ◽  
Short Review ◽  
Effector Proteins ◽  
Muscle Disease ◽  
Disease Genes ◽  
Protein Protein Interaction ◽  
Interaction Partners ◽  
And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

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