Relationships between extractable Ni, Co, and other metals and some microbiological characteristics of different ultramafic soils from New Caledonia

Soil Research ◽  
2003 ◽  
Vol 41 (2) ◽  
pp. 215 ◽  
Author(s):  
Hamid Amir ◽  
René Pineau
Keyword(s):  
Microbial Activity ◽  
New Caledonia ◽  
Ultramafic Soils ◽  
Ultramafic Soil ◽  
High Metal Content ◽  
Microbial Density ◽  
Microbiological Characteristics ◽  
Physico Chemical ◽  
Highly Correlated

New Caledonian ultramafic soils have relatively high metal content, which normally induces toxicity in plants and microflora. The relationships between extractable metal concentrations, especially Ni and Co, and different microbiological factors were analysed by statistical methods. For this purpose, some physico-chemical and microbiological characteristics of 40 ultramafic soil samples were estimated: organic carbon, pH, extractable metals (Ni, Co, Fe, Mn and Mg), microbial density, total microbial activity and percentage of microorganisms tolerant to Ni. Total, partial, and multiple correlation analyses are reported. The release of metals (measured by their extractablity) into these soils appeared to be related to microbial activity; the link with pH was not clear. A laboratory experiment confirmed the role of the microflora in the release of Ni and Co, which were not previously known to be released by microbial processes in soil. The percentage of microorganisms tolerant to Ni was highly correlated to the extractable concentration of this metal in the soils.

Release of Ni and Co by microbial activity in New Caledonian ultramafic soils

2003 ◽  
Vol 49 (4) ◽  
pp. 288-293 ◽  
Author(s):  
Hamid Amir ◽  
René Pineau
Keyword(s):  
Microbial Activity ◽  
New Caledonia ◽  
Ultramafic Soils ◽  
Metal Release ◽  
Release Process ◽  
High Positive Correlation ◽  
Ultramafic Soil ◽  
Heat Treated ◽  
Native Microflora ◽  
Amended Soil

A high positive correlation was found between extractable Ni and Co contents and microbial activity of 40 ultramafic soil samples from New Caledonia, suggesting a possible role of microorganisms in the release of these two metals. A saprolite (ultramafic subsoil) and a hypermagnesian brown soil were incubated 9 months in different conditions. Ni and Co release, measured by their extractability, occurred without reduction of soil pH but did not occur when the native microflora was eliminated by heat treatment. However, when autoclaved soil was re-inoculated with a pinch of the same nonheated soil, the release of metals was recorded. The concentrations of extractable Ni and Co were much higher in soils amended with organic compounds in which microbial activity was enhanced, but only if the soil was not heat treated. The presence of Grevillea exul, a metal-tolerant plant, stimulated the metal release process, but the stimulation was less effective than it was in the compost-amended soil without plant. The influence of the plant in extractable Ni and Co contents in this amended soil was not significant. The release of the two metals therefore seemed to be induced by the activity of specialized organotrophic microorganisms.Key words: Co, Ni, metal release, microbial activity, ultramafic soils.

Revision of Pichonia (Sapotaceae) in New Caledonia

2012 ◽  
Vol 25 (1) ◽  
pp. 31 ◽  
Author(s):  
Ulf Swenson ◽  
Jérôme Munzinger
Keyword(s):  
New Caledonia ◽  
Iucn Red List ◽  
Red List ◽  
Ultramafic Soils ◽  
Humid Forest ◽  
Ultramafic Soil ◽  
Canopy Tree ◽  
The North ◽  
One New Species ◽  
Small Genus

Pichonia Pierre (Sapotaceae, Chrysophylloideae) is a small genus of 10 species in Australasia, of which seven are endemic to New Caledonia. We revise the genus for New Caledonia and describe one new species (P. grandiflora), resurrect another (P. dubia) and make two new combinations because of nomenclatural priority (P. balansae, P. deplanchei). P. balansae has been known for decades as P. calomeris, a name that in fact has never been validly published. The members are mainly found in Grande Terre, the main island of New Caledonia, but two species extend to Belep Islands in the north and to Isle of Pines in the south of the archipelago. Most grow in maquis vegetation at low altitudes, on ultramafic soils, preferably serpentinite. The exceptions are P. balansana, confined to limestone areas, and P. dubia that is a large canopy tree of the humid forest on ultramafic soil. Pichonia is distinguished by a character combination of an areolate higher venation, staminodes, a single-seeded fruit, plano-convex cotyledons and absence of endosperm. Because of being restricted to ultramafic soils, they are subsequently sensitive to present and future mining activities in New Caledonia. Hence, preliminary IUCN Red List assessments for all members are provided. P. balansana, P. daenikeri and P. lecomtei are all naturally uncommon, do not occur in any protected area and are proposed the IUCN status of Vulnerable. The herein described species P. grandiflora is rare in nature, known only from the Boulinda–Paéoua–Kopéto Mountains, and is in urgent need of protection. It is therefore assigned a preliminary status of Endangered.

scholarly journals Natural starter culture on artisanal cheese

2020 ◽  
Vol 9 (10) ◽  
pp. e3039108604
Author(s):  
Marcus Welbert Lempk ◽  
Afonso de Liguori Oliveira ◽  
Roberto Gonçalves Junqueira ◽  
Eliara Acipreste Hudson ◽  
Ana Clarissa dos Santos Pires ◽  
...  
Keyword(s):  
Dry Matter ◽  
Scientific Literature ◽  
Starter Culture ◽  
New Horizons ◽  
Microbiological Characteristics ◽  
Physico Chemical ◽  
The Government ◽  
Government Legislation ◽  
And Staphylococcus Aureus

The use of natural starter culture in the manufacture of artisanal Minas cheeses is required by the government legislation in Brazil. However, there are no scientific support on role of the natural starter culture in these cheeses. The aim of this work was to compare artisanal Minas cheeses produced with and without natural starter culture to verify the influence on the physico-chemical and microbiological characteristics during the ripening process. The use of natural starter culture did not have a significant effect on the physico-chemical (dry matter, humidity, fat, pH, chlorides, water activity, ash, total protein, depth and extent of proteolysis) and microbiological (Escherichia coli, coliforms and Staphylococcus aureus) properties of the cheeses. The significant changes that occurred in the cheeses were mainly because of the ripening time. According to obtained results, natural starter has shown to be innocuous to traditional Minas Serro cheese. The present study is pioneering in the scientific literature and opens new horizons for the understanding of the requirement to use natural starter culture.

Activation of cytochrome c to a peroxidase compound I-type intermediate by H2O2: relevance to redox signalling in apoptosis

2004 ◽  
Vol 71 ◽  
pp. 97-106 ◽  
Author(s):  
Mark Burkitt ◽  
Clare Jones ◽  
Andrew Lawrence ◽  
Peter Wardman
Keyword(s):  
Cytochrome C ◽  
Hydroxyl Radical ◽  
Redox Regulation ◽  
Chemotherapeutic Agents ◽  
Tyrosyl Radical ◽  
Compound I ◽  
Definitive Evidence ◽  
Enhanced Production ◽  
Physico Chemical

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

THYROID STIMULATORS AND THYROID STIMULATION

1971 ◽  
Vol 66 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Gerald Burke
Keyword(s):  
Regulatory System ◽  
Control Site ◽  
Thyroid Cell ◽  
Primary Control ◽  
Physico Chemical ◽  
Site Of Action ◽  
Long Acting

ABSTRACT A long-acting thyroid stimulator (LATS), distinct from pituitary thyrotrophin (TSH), is found in the serum of some patients with Graves' disease. Despite the marked physico-chemical and immunologic differences between the two stimulators, both in vivo and in vitro studies indicate that LATS and TSH act on the same thyroidal site(s) and that such stimulation does not require penetration of the thyroid cell. Although resorption of colloid and secretion of thyroid hormone are early responses to both TSH and LATS, available evidence reveals no basic metabolic pathway which must be activated by these hormones in order for iodination reactions to occur. Cyclic 3′, 5′-AMP appears to mediate TSH and LATS effects on iodination reactions but the role of this compound in activating thyroidal intermediary metabolism is less clear. Based on the evidence reviewed herein, it is suggested that the primary site of action of thyroid stimulators is at the cell membrane and that beyond the(se) primary control site(s), there exists a multifaceted regulatory system for thyroid hormonogenesis and cell growth.

The Influence of Benthic Biota on Copper Speciation and Distribution in Freshwater-Sediment Systems

1981 ◽  
Vol 16 (1) ◽  
pp. 45-58 ◽  
Author(s):  
G. Krantzberg ◽  
P.M. Stokes
Keyword(s):  
Freshwater Sediment ◽  
Benthic Macroinvertebrate ◽  
Macroinvertebrate Communities ◽  
Copper Species ◽  
Copper Speciation ◽  
Physico Chemical ◽  
Macro Benthos

Abstract An investigation was made of the effects exerted by benthic macroinvertebrate communities on copper speciation in sediments from a lake which is becoming acidified. In laboratory microcosms, benthic macroinvertebrate communities stimulated the flux of copper from sediment to water. The presence of the macro-benthos resulted in a redistribution of physico-chemical copper species within the sediment with a transfer from more strongly complexed forms (HC1 extractable) to adsorbed and cation exchangeable forms (MgCl2 extractable). The role of bio-turbation in copper transformations is discussed.

Methyl mercury in the dutch rhine delta

1994 ◽  
Vol 30 (10) ◽  
pp. 213-219 ◽  
Author(s):  
Hendrik Pieters ◽  
Victor Geuke
Keyword(s):  
Suspended Matter ◽  
Methyl Mercury ◽  
Mercury Contamination ◽  
Benthic Organisms ◽  
Considerable Decrease ◽  
Continuous Sedimentation ◽  
Highly Correlated ◽  
High Level ◽  
Almost All

Samples of yellow eel from various locations in the Dutch Rhine area have been analyzed for trend monitoring of mercury since 1977. In the western Rhine delta mercury levels in eels have hardly changed since the seventies, whereas in the eastern part of the Dutch Rhine area a considerable decrease of mercury concentrations in eel has occurred. Because of continuous sedimentation of contaminated suspended matter transported from upstream regions, accumulation rates and concentrations of mercury in eel in the western Rhine delta remained at a relatively high level. Analyses of methyl mercury in biota have been performed to elucidate the role of methyl mercury in the mercury contamination of the Dutch Rhine ecosystem. Low percentages of methyl mercury were observed in zooplankton (3 to 35%). In benthic organisms (mussels) percentages of methyl mercury ranged from 30 to 57%, while in fish species and liver of aquatic top predator birds almost all the mercury was present in the form of methyl mercury (> 80%). During the period 1970-1990 mercury concentrations of suspended matter in the eastern Rhine delta have drastically decreased. These concentrations seemed to be highly correlated with mercury concentrations of eel (R = 0.84). The consequences of this relation are discussed.

scholarly journals PPM1G promotes the progression of hepatocellular carcinoma via phosphorylation regulation of alternative splicing protein SRSF3

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Dawei Chen ◽  
Zhenguo Zhao ◽  
Lu Chen ◽  
Qinghua Li ◽  
Jixue Zou ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Alternative Splicing ◽  
Protein Function ◽  
Vital Role ◽  
Normal Tissues ◽  
Mechanistic Analysis ◽  
Highly Correlated ◽  
Splicing Patterns

AbstractEmerging evidence has demonstrated that alternative splicing has a vital role in regulating protein function, but how alternative splicing factors can be regulated remains unclear. We showed that the PPM1G, a protein phosphatase, regulated the phosphorylation of SRSF3 in hepatocellular carcinoma (HCC) and contributed to the proliferation, invasion, and metastasis of HCC. PPM1G was highly expressed in HCC tissues compared to adjacent normal tissues, and higher levels of PPM1G were observed in adverse staged HCCs. The higher levels of PPM1G were highly correlated with poor prognosis, which was further validated in the TCGA cohort. The knockdown of PPM1G inhibited the cell growth and invasion of HCC cell lines. Further studies showed that the knockdown of PPM1G inhibited tumor growth in vivo. The mechanistic analysis showed that the PPM1G interacted with proteins related to alternative splicing, including SRSF3. Overexpression of PPM1G promoted the dephosphorylation of SRSF3 and changed the alternative splicing patterns of genes related to the cell cycle, the transcriptional regulation in HCC cells. In addition, we also demonstrated that the promoter of PPM1G was activated by multiple transcription factors and co-activators, including MYC/MAX and EP300, MED1, and ELF1. Our study highlighted the essential role of PPM1G in HCC and shed new light on unveiling the regulation of alternative splicing in malignant transformation.

Characteristics of educators’ talk about decontextualised events

2020 ◽  
Vol 45 (4) ◽  
pp. 362-376
Author(s):  
Rebecca Andrews ◽  
Penny Van Bergen
Keyword(s):  
Communication Skills ◽  
Future Event ◽  
Time Points ◽  
Long Day ◽  
Future Events ◽  
Day Care Centres ◽  
Highly Correlated ◽  
Children’S Thinking ◽  
Sydney Australia

This study investigated the characteristics of educators’ talk about decontextualised events with young children in seven early childhood long day care centres in Sydney, Australia. Educators were partnered with up to six children aged between 27 and 60 months. Across two time points, 85 educator–child dyads discussed past and future events. Educators’ use of questions, contextual statements, evaluations and prompts and children’s use of questions, open-ended responses, yes-no responses and spontaneous information statements were examined. Educators’ evaluative statements were highly correlated and educators’ questions were moderately correlated with children’s open-ended responses in past event conversations. Educators’ evaluative statements were highly correlated with children’s open-ended responses in future event conversations and were the only significant predictor for children’s talk. Given the important role of educators in scaffolding children’s thinking and communication skills, the recommended strategies for educators’ talk in decontextualised conversations include: sharing the conversational load, making frequent contextual statements and following the child’s lead/interests.

scholarly journals Occurrence of drug target residues within decantation tank sediments: a good clue to assess their historical excretion?

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Thomas Thiebault ◽  
Laëtitia Fougère ◽  
Anaëlle Simonneau ◽  
Emilie Destandau ◽  
Claude Le Milbeau ◽  
...  
Keyword(s):  
Drug Target ◽  
Chemical Properties ◽  
Deposition Process ◽  
Drug Consumption ◽  
Organic Layers ◽  
Sewer Systems ◽  
Physico Chemical ◽  
Deep Underground ◽  
Deposition Processes

AbstractThis study investigated the potential of sediments accumulated in sewer systems to record human activities through the occurrence of drug target residues (DTR). The installation studied is 17 m deep underground decantation tank that traps the coarse fractions of a unitary sewer system (northern part of Orléans, France), collecting both stormwater and wastewater. The sediments deposited in this tank could constitute a nonesuch opportunity to study the historical evolution of illicit and licit drug consumption in the catchment, however, the deposition processes and the record of DTRs remain largely unknown at present. Five cores were acquired from 2015 to 2017. One hundred fifty-two sediment samples were extracted using a mixture of ultra-pure water:methanol (1:1) prior to analysis of the extracts by high-pressure liquid chromatography coupled to tandem mass spectrometry. Several classical sedimentological analyses such as total organic carbon, facies description and granulometry were also performed on these samples, in order to understand the most important factors (e.g., physico-chemical properties of the DTRs, solid type, assumed load in wastewater) impacting their deposition.The key role of the speciation of DTRs was highlighted by the higher contents in neutral and anionic DTRs in organic layers, whereas only cationic DTRs were found in mineral layers. The considerable modifications in the sediments’ properties, generated by distinct origins (i.e., stormwater or wastewater), are therefore the most important drivers that must be taken into account when back-calculating the historical patterns of drug consumption from their DTR concentrations in decantation tank sediments. Further research remains necessary to fully understand the deposition process, but this study provides new clues explaining these temporal evolutions.

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