The Impact of Heap Self-Heating on Microbial Activity during the Bioleaching of Low-Grade Copper Sulfide Ores

2017 ◽  
Vol 262 ◽  
pp. 233-236 ◽  
Author(s):  
Denis W. Shiers ◽  
David M. Collinson ◽  
Helen R. Watling
Keyword(s):  
Biological Activity ◽  
Copper Sulfide ◽  
Temperature Increase ◽  
Low Grade ◽  
Sulfide Ores ◽  
Moderately Thermophilic ◽  
Cell Numbers ◽  
Self Heating ◽  
Rapid Temperature ◽  
The Impact

In this study, a dynamically-controlled column was used to evaluate two ores known to cause heap overheating. This enabled the simulation of heap self-heating under controlled conditions. The lixiviant was inoculated with a consortia of mesophilic and moderately thermophilic microorgaisms, and the impact of rapid temperature increases on biological activity and cell numbers was evaluated. During the leaching of ore sample A, the temperature lagged for 29 days before increasing rapidly from 26 to 88 °C. Cell numbers and solution potential increased concomitantly, before both were reduced as the temperature increased past maximum microbial tolerances. Cell numbers began increasing again within 10 days of reaching temperatures that would facilitate mesophilic growth being restored. During the leaching of ore B, the temperature lagged for 4 days before exhibiting a rapid increase in temperature, increasing from 30 to 76 °C over a six-day period. Cell numbers were reduced with the sudden temperature increase, and did not recover over the remainder of the experiment.

Effect of Bio-Leaching Process on the Pore Structure of Packed Particle Bed via 3D Imaging and Analysis

2013 ◽  
Vol 825 ◽  
pp. 344-347 ◽  
Author(s):  
Ai Xiang Wu ◽  
Bao Hua Yang ◽  
Jin Zhi Liu ◽  
Xiu Xiu Miao
Keyword(s):  
Pore Structure ◽  
Copper Sulfide ◽  
3D Imaging ◽  
Heap Leaching ◽  
Low Grade ◽  
Sulfide Ores ◽  
Ct Scanner ◽  
Packed Particle ◽  
Leaching Process ◽  
Particle Beds

Heap bio-leaching technology is extensively applied to recover metals from low-grade complex ores in the mining industry, particularly the copper sulfide ores. Understanding the effect of bio-leaching process on the pore structure of packed particle beds is important to enhance the percolation and leaching performances with respect to design and operation of heap leaching system. The porosity, pore size distribution and degree of pore connectivity are the three most important features correlated with fluid flow in heap leaching operation. In this study, a spiral X-ray CT scanner, combined with 3D imaging and analysis, was used to characterize the complex pore structure of the packed ore particle beds before and after bioleaching copper sulfide ores. The results indicate that the pore structure has temporal and spatial variations during bio-leaching process.

Bioleaching of low-grade copper sulfide ores by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans

2014 ◽  
Vol 21 (2) ◽  
pp. 728-734 ◽  
Author(s):  
Jun Wang ◽  
Shan Zhu ◽  
Yan-sheng Zhang ◽  
Hong-bo Zhao ◽  
Ming-hao Hu ◽  
...  
Keyword(s):  
Acidithiobacillus Ferrooxidans ◽  
Copper Sulfide ◽  
Low Grade ◽  
Acidithiobacillus Thiooxidans ◽  
Sulfide Ores

scholarly journals Consumption of Select Dietary Emulsifiers Exacerbates the Development of Spontaneous Intestinal Adenoma

2021 ◽  
Vol 22 (5) ◽  
pp. 2602
Author(s):  
Emilie Viennois ◽  
Benoit Chassaing
Keyword(s):  
Intestinal Inflammation ◽  
Tumor Development ◽  
Low Grade ◽  
Gastrointestinal Cancers ◽  
Cancer Initiation ◽  
And Function ◽  
The Impact ◽  
Chronic Intestinal Inflammation ◽  
Low Grade Inflammation ◽  
Intestinal Adenoma

Inflammation is a well-characterized critical driver of gastrointestinal cancers. Previous findings have shown that intestinal low-grade inflammation can be promoted by the consumption of select dietary emulsifiers, ubiquitous component of processed foods which alter the composition and function of the gut microbiota. Using a model of colitis-associated cancer, we previously reported that consumption of the dietary emulsifiers carboxymethylcellulose or polysorbate-80 exacerbated colonic tumor development. Here, we investigate the impact of dietary emulsifiers consumption on cancer initiation and progression in a genetical model of intestinal adenomas. In APCmin mice, we observed that dietary emulsifiers consumption enhanced small-intestine tumor development in a way that appeared to be independent of chronic intestinal inflammation but rather associated with emulsifiers’ impact on the proliferative status of the intestinal epithelium as well as on intestinal microbiota composition in both male and female mice. Overall, our findings further support the hypothesis that emulsifier consumption may be a new modifiable risk factor for colorectal cancer (CRC) and that alterations in host–microbiota interactions can favor gastrointestinal carcinogenesis in individuals with a genetical predisposition to such disorders.

scholarly journals QOL-36. USE OF CANNABINOIDS IN THE PEDIATRIC CENTRAL NERVOUS SYSTEM TUMOR POPULATION

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii438-iii438
Author(s):  
Kathleen Dorris ◽  
Jessica Channell ◽  
Ashley Mettetal ◽  
Molly Hemenway ◽  
Natalie Briones ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Central Nervous System ◽  
Nervous System ◽  
Cell Activity ◽  
Cns Tumors ◽  
Low Grade ◽  
Tumor Type ◽  
Central Nervous System Tumor ◽  
The Impact

Abstract BACKGROUND Cannabinoids, including cannabidiol (CBD) and tetrahydrocannabinol (THC), are a class of compounds found in marijuana. Numerous studies in adults have examined cannabinoid use in management of cancer-related symptoms such as nausea, anorexia, and pain. Less is known about the use in the pediatric oncology population. METHODS A prospective observational study has been ongoing since 2016 at Children’s Hospital Colorado to evaluate cannabinoids’ impact using PedsQL™ modules on quality of life of pediatric patients with central nervous system (CNS) tumors who are 2–18 years old. Laboratory assessments of T-cell activity and pharmacokinetics of CBD, THC and associated metabolites are in process. Diaries with exploratory information on cannabinoid use patterns are being collected. RESULTS Thirty-three patients (14:19; male:female) have been enrolled with a median age of 6.4 years (range, 2.9–17.7 years). The most common tumor type in enrolled patients is embryonal tumors (13/33; 39%). Nine (27%) patients have low-grade glial/glioneuronal tumors, and eight (24%) had high-grade/diffuse midline gliomas. The remaining patients had ependymoma or craniopharyngioma. The median time on cannabinoids is 9 months. Most (n=20) patients have used oral products with CBD and THC. One patient continues on cannabinoid therapy in follow up. Preliminary immune function analyses identified impaired neutrophil superoxide anion production and chemotaxis in patients taking cannabinoids at early time points on therapy. CONCLUSIONS Families of children with various CNS tumors are pursuing cannabinoid therapy for both antitumor and supportive care purposes. Analysis of the impact of cannabinoids on patients’ quality of life is ongoing.

scholarly journals Synthesis and Biological Activity of Brassinosteroid Analogues with a Nitrogen-Containing Side Chain

2020 ◽  
Vol 22 (1) ◽  
pp. 155
Author(s):  
Mikhail V. Diachkov ◽  
Karoll Ferrer ◽  
Jana Oklestkova ◽  
Lucie Rarova ◽  
Vaclav Bazgier ◽  
...  
Keyword(s):  
Biological Activity ◽  
Functional Groups ◽  
Side Chain ◽  
Biotic And Abiotic Stresses ◽  
Short Side ◽  
Arabidopsis Root ◽  
Physiological Processes ◽  
Growth Promoting ◽  
The Impact ◽  
Brassinosteroid Analogues

Brassinosteroids are a class of plant hormones that regulate a broad range of physiological processes such as plant growth, development and immunity, including the suppression of biotic and abiotic stresses. In this paper, we report the synthesis of new brassinosteroid analogues with a nitrogen-containing side chain and their biological activity on Arabidopis thaliana. Based on molecular docking experiments, two groups of brassinosteroid analogues were prepared with short and long side chains in order to study the impact of side chain length on plants. The derivatives with a short side chain were prepared with amide, amine and ammonium functional groups. The derivatives with a long side chain were synthesized using amide and ammonium functional groups. A total of 25 new brassinosteroid analogues were prepared. All 25 compounds were tested in an Arabidopsis root sensitivity bioassay and cytotoxicity screening. The synthesized substances showed no significant inhibitory activity compared to natural 24-epibrassinolide. In contrast, in low concentration, several compounds (8a, 8b, 8e, 16e, 22a and 22e) showed interesting growth-promoting activity. The cytotoxicity assay showed no toxicity of the prepared compounds on cancer and normal cell lines.

scholarly journals A Retrospective Experience of Helicobacter pylori Histology in a Large Sample of Subjects in Northern Italy

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 650
Author(s):  
Davide Giuseppe Ribaldone ◽  
Carlo Zurlo ◽  
Sharmila Fagoonee ◽  
Chiara Rosso ◽  
Angelo Armandi ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Large Population ◽  
Population Data ◽  
Signet Ring Cell ◽  
Current Data ◽  
Low Grade ◽  
Gastric Cardia Adenocarcinoma ◽  
Significant Difference ◽  
H Pylori ◽  
The Impact

Updated data about the prevalence of Helicobacter pylori (H. pylori) and its correlation with histological results are scarce. The aim of our study was to provide current data on the impact of H. pylori in a third-level endoscopy service. We performed a large, retrospective study analyzing the results of all histological samples of gastroscopy from the year 2019. In total, 1512 subjects were included. The prevalence of H. pylori was 16.8%. A significant difference between the prevalence in subjects born in Italy and those from eastern Europe, south America, or Africa was found (p < 0.0001, p = 0.006, and p = 0.0006, respectively). An association was found between H. pylori and active superficial gastritis (p < 0.0001). Current H. pylori and/or a previous finding of H. pylori was related to antral atrophy (p < 0.0001). Fifteen patients had low-grade dysplasia. There were no statistically significant associations with current or past H. pylori infection. One patient presented gastric cardia adenocarcinoma with regular gastric mucosa. One patient, H. pylori positive, was diagnosed with gastric signet ring cell adenocarcinoma in a setting of diffuse atrophy, without metaplasia.. Our study provides updated, solid (biopsy diagnosis and large population) data on the prevalence of H. pylori infection in a representative region of southern Europe.

scholarly journals Comparison of Osmotic Resistance, Shape and Transmembrane Potential of Erythrocytes Collected from Healthy and Fed with High Fat-Carbohydrates Diet (HF-CD) Pigs—Protective Effect of Cistus incanus L. Extracts

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1050
Author(s):  
Sylwia Cyboran-Mikołajczyk ◽  
Robert Pasławski ◽  
Urszula Pasławska ◽  
Kacper Nowak ◽  
Michał Płóciennik ◽  
...  
Keyword(s):  
Biological Activity ◽  
Physical Properties ◽  
Plasma Lipid ◽  
Membrane Lipid ◽  
Osmotic Resistance ◽  
High Fat ◽  
Atherosclerotic Lesions ◽  
Cistus Incanus ◽  
Osmotic Resistance Of Erythrocytes ◽  
The Impact

Long-term high fat-carbohydrates diet (HF-CD) contributes to the formation of irreversible changes in the organism that lead to the emergence of civilization diseases. In this study, the impact of three-month high-fat diet on the physical properties of erythrocytes (RBCs) was studied. Furthermore, the biological activity of Cistus incanus L. extracts, plant known with high pro-health potential, in relation to normal and HF-CD RBCs, was determined. Obtained results have shown that, applied HF-CD modified shape, membrane potential and osmotic resistance of erythrocytes causing changes in membrane lipid composition and the distribution of lipids. The impact of HF-CD on physical properties of RBCs along with atherosclerotic lesions of the artery was visible, despite the lack of statistically significant changes in blood morphology and plasma lipid profile. This suggests that erythrocytes may be good markers of obesity-related diseases. The studies of biological activity of Cistus incanus L. extracts have demonstrated that they may ameliorate the effect of HF-CD on erythrocytes through the membrane-modifying and antioxidant activity.

scholarly journals TissueCypher Barrett’s esophagus assay impacts clinical decisions in the management of patients with Barrett’s esophagus

2021 ◽  
Vol 09 (03) ◽  
pp. E348-E355
Author(s):  
David L. Diehl ◽  
Harshit S. Khara ◽  
Nasir Akhtar ◽  
Rebecca J. Critchley-Thorne
Keyword(s):  
High Risk ◽  
Barrett’S Esophagus ◽  
Barrett's Esophagus ◽  
Clinical Decision Making ◽  
Eradication Therapy ◽  
Low Risk ◽  
Management Approach ◽  
Low Grade ◽  
Management Decisions ◽  
The Impact

Abstract Background and study aims The TissueCypher Barrett’s Esophagus Assay is a novel tissue biomarker test, and has been validated to predict progression to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett’s esophagus (BE). The aim of this study was to evaluate the impact of TissueCypher on clinical decision-making in the management of BE. Patients and methods TissueCypher was ordered for 60 patients with non-dysplastic (ND, n = 18) BE, indefinite for dysplasia (IND, n = 25), and low-grade dysplasia (LGD, n = 17). TissueCypher reports a risk class (low, intermediate or high) for progression to HGD or EAC within 5 years. The impact of the test results on BE management decisions was assessed. Results Fifty-two of 60 patients were male, mean age 65.2 ± 11.8, and 43 of 60 had long segment BE. TissueCypher results impacted 55.0 % of management decisions. In 21.7 % of patients, the test upstaged the management approach, resulting in endoscopic eradication therapy (EET) or shorter surveillance interval. The test downstaged the management approach in 33.4 % of patients, leading to surveillance rather than EET. In the subset of patients whose management plan was changed, upstaging was associated with a high-risk TissueCypher result, and downstaging was associated with a low-risk result (P < 0.0001). Conclusions TissueCypher was used as an adjunct to support a surveillance-only approach in 33.4 % of patients. Upstaging occurred in 21.7 % of patients, leading to therapeutic intervention or increased surveillance. These results indicate that the TissueCypher test may enable physicians to target EET for TissueCypher high-risk BE patients, while reducing unnecessary procedures in TissueCypher low-risk patients.

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