Role of geochemical barriers in forming sulfide ores in various geological environments

2021 ◽  
pp. 63-73
Author(s):  
IRINA GABLINA
Keyword(s):  
Sulfide Ores ◽  
Atlantic Region ◽  
Geochemical Barriers ◽  
Sulfide Ore ◽  
Cupriferous Sandstone ◽  
Central Atlantic ◽  
Ore Types ◽  
Long Term Studies

Based on long-term studies of cupriferous sandstone and shale deposits, as well as deepsea sulfide ores, various types of geochemical barriers where sulfides form are shown. Cupriferous sandstones and shales form as metals precipitate from redbed reservoir waters on H2S geochemical barrier. Syngenetic and epigenetic barrier types are identified. Oceanic sulfide ores from the Central Atlantic region were studied; as a result, a new hydrothermal-metasomatic sediment-hosted mineralization type was found, along with previously known sulfide ore types (massive ores on the seafloor and stockwork ores in substrate rocks). Geochemical seafloor sulfide formation environments and those in biogenic carbonate bottom sediments are examined.

The Role of Bioactive Compounds and other Metabolites from Mushrooms against Skin Disorders- A Systematic Review Assessing their Cosmeceutical and Nutricosmetic Outcomes

2020 ◽  
Vol 27 (41) ◽  
pp. 6926-6965
Author(s):  
Oludemi Taofiq ◽  
Maria Filomena Barreiro ◽  
Isabel C.F.R. Ferreira
Keyword(s):  
Systematic Review ◽  
Bioactive Compounds ◽  
Skin Diseases ◽  
Scientific Data ◽  
Inflammatory Skin Diseases ◽  
Toxicological Studies ◽  
Pros And Cons ◽  
Long Term Studies

Bioactive compounds derived from mushrooms have been shown to present promising potential as cosmeceutical or nutricosmetic ingredients. Scientific data reviewed herein showed that extracts prepared from medicinal and edible mushrooms and their individual metabolites presented antiinflammatory, antioxidant, photoprotective, antimicrobial, anti-tyrosinase, anti-elastase, and anticollagenase activities. These metabolites can be utilised as ingredients to suppress the severity of Inflammatory Skin Diseases, offer photoprotection to the skin, and correct Hyperpigmentation. However, studies regarding the molecular mechanism behind the mentioned bioactivities are still lacking. Challenges associated with the use of mushroom extracts and their associated metabolites as cosmeceutical and nutricosmetic ingredients include several steps from the fruiting bodies to the final product: extraction optimization, estimation of the efficacy and safety claims, the use of micro and nanocarriers to allow for controlled release and the pros and cons associated with the use of extracts vs individual compounds. This systematic review highlights that mushrooms contain diverse biomolecules that can be sustainably used in the development of nutricosmetic and cosmeceutical formulations. Reports regarding stability, compatibility, and safety assessment, but also toxicological studies are still needed to be considered. Furthermore, some of the constraints and limitations hindering the development of this type of ingredients still require long-term studies to achieve major breakthroughs.

How do habitat and climate variation affect phenology of the Amazonian palm, Mauritia flexuosa?

2013 ◽  
Vol 29 (3) ◽  
pp. 255-259 ◽  
Author(s):  
Roxaneh Khorsand Rosa ◽  
Reinaldo Imbrozio Barbosa ◽  
Suzanne Koptur
Keyword(s):  
Sex Ratios ◽  
Climatic Variation ◽  
Fruit Maturation ◽  
Wet Season ◽  
Short Term ◽  
Mauritia Flexuosa ◽  
Males And Females ◽  
Long Term Studies

Abstract:Although the dioecious palm, Mauritia flexuosa plays a pivotal role in Amazonian ecology and economy, little is known about its flowering and fruiting patterns. We investigated the role of habitat and inter-annual precipitation in the phenology of M. flexuosa. We calculated sex ratios and recorded phenology for 20 mo in four populations (N = 246) of savanna–forest ecotone (two sites) and forest (two sites) habitat in Roraima, Brazilian Amazonia. Sex ratios were significantly female-biased, and >98% of females set fruit. No significant relationship was found between habitat and sex. Flowering occurred at the wet/dry season interface (August–November), and fruit maturation occurred during the wet season (May–August). Males and females flowered synchronously, and neither the onset nor termination of flowering differed significantly between habitats. Flowering was negatively associated with present precipitation and positively correlated with prior precipitation (3 mo). Fruiting was positively associated with present precipitation and unrelated to prior precipitation (3 mo). We conclude that habitat has an insignificant effect, although short-term climatic variation may influence phenology of this species in northern Amazonia. These results highlight the need for long-term studies relating flowering and fruiting events, and inter-annual climatic variation.

‘Never so at home’: Charles Elton and the Woods of Wytham

2021 ◽  
Author(s):  
Georgina M. Montgomery
Keyword(s):  
Ecological Site ◽  
The People ◽  
As Species ◽  
History Of ◽  
A Site ◽  
Scientific Value ◽  
Scientific Environment ◽  
Long Term Studies

Focusing on the history of an ecological site northwest of Oxford, UK, this essay explores the people, research and values behind the development of Wytham Woods as a scientific environment. A small patch of woodland, Wytham has long been identified by ecologists as a site of great scientific value. In addition to traditional sources of scientific value, such as species diversity, this article examines the role of emotional connection and aesthetics in how scientific sites are formed and maintained over long periods of time. As such, this history of Wytham Woods sheds light on the multiple factors that nurture the relationships formed when researchers dedicate decades to long-term studies conducted in specific scientific environments.

scholarly journals Nutritional issues for older adults: addressing degenerative ageing with long-term studies

2016 ◽  
Vol 75 (2) ◽  
pp. 169-173 ◽  
Author(s):  
Lisette C. P. G. M. de Groot
Keyword(s):  
Dietary Patterns ◽  
Later Life ◽  
Ageing Process ◽  
Vitamin B ◽  
Epidemiological Evidence ◽  
Important Challenge ◽  
Different Dimensions ◽  
Long Term Studies

The ageing process is influenced by a variety of factors, including extrinsic, malleable lifestyle variables. The present paper deals with the epidemiological evidence for the role of dietary patterns and key nutritional concerns in relation to survival and ageing-related disorders that present themselves in later life. Healthful dietary patterns appear to be most relevant in old age. Specific nutritional concerns are related to vitamin D, vitamin B12 and protein malnutrition. An important challenge to further expand the knowledge base is currently addressed by the NuAge project, acknowledging the complexity of the ageing process and integrating different dimensions of research into human healthy ageing. In the meantime, reversing poor adherence to existing guidelines for a healthy diet remains a first challenge in public health nutritional practices.

Re-examining the role of benzodiazepines in the treatment of schizophrenia: A systematic review

2014 ◽  
Vol 29 (2) ◽  
pp. 212-223 ◽  
Author(s):  
Faye Sim ◽  
Isabel Sweetman ◽  
Shitij Kapur ◽  
Maxine X Patel
Keyword(s):  
Clinical Practice ◽  
First Generation ◽  
Outcome Data ◽  
Short Term ◽  
Global Improvement ◽  
Conflicting Evidence ◽  
Randomised Controlled ◽  
Long Term Studies

Background Benzodiazepine prescribing for schizophrenia occurs in clinical practice and antipsychotic trials. This review examined the clinical outcomes for benzodiazepines in schizophrenia. Method A systematic search identified randomised controlled trials that evaluated benzodiazepines in comparison with placebo or antipsychotics, and also as adjuncts to antipsychotics. Relevant clinical outcome data was extracted. Results Twenty six studies were included with some reporting multiple comparisons. Seven short-term studies compared benzodiazepines with placebo: benzodiazepine superiority was found in two out of five studies for global improvements and two out of four studies for psychiatric/behavioural outcomes. Eleven studies compared benzodiazepines with first-generation antipsychotics (FGAs): four out of nine studies (including two long-term studies) reported greater global improvements for antipsychotics; four out of five studies showed no treatment differences for psychiatric/behavioural outcomes. Fourteen studies compared benzodiazepines (as adjunct to antipsychotics) vs antipsychotics alone (mostly FGAs); benzodiazepine superiority was found for global improvement in one out of eight studies and inferiority in two out of eight short-term studies whereas superiority was found for psychiatric/behavioural outcomes in three out of 12 short-term studies and inferiority in three out of 12 studies. Conclusion Benzodiazepine superiority over placebo was found for global, psychiatric and behavioural outcomes, but inferiority to antipsychotics on longer-term global outcomes. Conflicting evidence exists regarding the addition of benzodiazepines to antipsychotics; thus the use of benzodiazepines in clinical practice and antipsychotic trials should be limited.

scholarly journals Science and Society: The Role of Long-Term Studies in Environmental Stewardship

BioScience ◽  
2012 ◽  
Vol 62 (4) ◽  
pp. 354-366 ◽  
Author(s):  
Charles T. Driscoll ◽  
Kathleen F. Lambert ◽  
F. Stuart Chapin ◽  
David J. Nowak ◽  
Thomas A. Spies ◽  
...  
Keyword(s):  
Environmental Stewardship ◽  
Science And Society ◽  
Long Term Studies
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