scholarly journals Selection of a suitable ligand for the supercritical extraction of gold from a low-grade refractory tailing

2021 ◽  
pp. 105415
Author(s):  
L.D. van Dyk ◽  
G. Mawire ◽  
J.H. Potgieter ◽  
M. Dworzanowski
Keyword(s):  
Supercritical Extraction ◽  
Low Grade ◽  
Selection Of

scholarly journals Selection of Optimal Magnets for Traction Motors to Prevent Demagnetization

Machines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 124
Author(s):  
Dantam Rao ◽  
Madhan Bagianathan
Keyword(s):  
Flux Density ◽  
Electric Vehicles ◽  
Parallel Line ◽  
Low Grade ◽  
Lower Grade ◽  
Worst Case ◽  
Traction Motors ◽  
Knee Point ◽  
Point Of Intersection ◽  
Selection Of

Currently, permanent-magnet-type traction motors drive most electric vehicles. However, the potential demagnetization of magnets in these motors limits the performance of an electric vehicle. It is well known that during severe duty, the magnets are demagnetized if they operate beyond a ‘knee point’ in the B(H) curve. We show herein that the classic knee point definition can degrade a magnet by up to 4 grades. To prevent consequent excessive loss in performance, this paper defines the knee point k as the point of intersection of the B(H) curve and a parallel line that limits the reduction in its residual flux density to 1%. We show that operating above such a knee point will not be demagnetizing the magnets. It will also prevent a magnet from degenerating to a lower grade. The flux density at such a knee point, termed demag flux density, characterizes the onset of demagnetization. It rightly reflects the value of a magnet, so can be used as a basis to price the magnets. Including such knee points in the purchase specifications also helps avoid the penalty of getting the performance of a low-grade magnet out of a high-grade magnet. It also facilitates an accurate demagnetization analysis of traction motors in the worst-case conditions.

scholarly journals Schistosomiasis: from established diagnostic assays to emerging micro/nanotechnology-based rapid field testing for clinical management and epidemiology

2019 ◽  
Vol 3 (1) ◽  
pp. 439-458 ◽  
Author(s):  
Maurice Mutro Nigo ◽  
Georgette Salieb-Beugelaar ◽  
Manuel Battegay ◽  
Peter Odermatt ◽  
Patrick Hunziker
Keyword(s):  
Point Of Care ◽  
Field Testing ◽  
Detection Methods ◽  
Low Grade ◽  
Analytical Strategy ◽  
Diagnostic Assays ◽  
And Control ◽  
Analytical Platforms ◽  
Selection Of

Schistosomiasis is a neglected invasive worm disease with a huge disease burden in developing countries, particularly in children, and is seen increasingly in non-endemic regions through transfer by travellers, expatriates, and refugees. Undetected and untreated infections may be responsible for the persistence of transmission. Rapid and accurate diagnosis is the key to treatment and control. So far, parasitological detection methods remain the cornerstone of Schistosoma infection diagnosis in endemic regions, but conventional tests have limited sensitivity, in particular in low-grade infection. Recent advances contribute to improved detection in clinical and field settings. The recent progress in micro- and nanotechnologies opens a road by enabling the design of new miniaturized point-of-care devices and analytical platforms, which can be used for the rapid detection of these infections. This review starts with an overview of currently available laboratory tests and their performance and then discusses emerging rapid and micro/nanotechnologies-based tools. The epidemiological and clinical setting of testing is then discussed as an important determinant for the selection of the best analytical strategy in patients suspected to suffer from Schistosoma infection. Finally, it discusses the potential role of advanced technologies in the setting near to disease eradication is examined.

scholarly journals Germline and somatic mutations of homologous recombination-associated genes in Japanese ovarian cancer patients

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kentaro Sugino ◽  
Ryo Tamura ◽  
Hirofumi Nakaoka ◽  
Nozomi Yachida ◽  
Manako Yamaguchi ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Homologous Recombination ◽  
Cancer Patients ◽  
Somatic Mutations ◽  
Clear Cell ◽  
Gene Mutations ◽  
Parp Inhibitors ◽  
Low Grade ◽  
Mmr Genes ◽  
Selection Of

AbstractWe explored the frequency of germline and somatic mutations in homologous recombination (HR)-associated genes in major histological types of ovarian cancer. We performed targeted sequencing to assess germline and somatic mutations of 16 HR-associated genes and 4 mismatch repair (MMR) genes among 207 ovarian cancer patients (50 high-grade serous carcinomas (HGSC), 99 clear cell carcinomas (CCC), 39 endometrioid carcinomas (EC), 13 mucinous carcinomas (MC), and 6 low-grade serous carcinomas (LGSC)). Germline or somatic mutations of HR-associated genes were detected in 44% of HGSC, 28% of CCC, 23% of EC, 16% of MC, and 17% of LGSC patients. The profile of HR-associated gene mutations was remarkably different among each histological type. Germline BRCA1/2 mutations were frequently detected in HGSC and were rarely observed in CCC, EC, and MC patients. ATM somatic mutation was more frequently detected in CCC (9%) and EC patients (18%) than in HGSC patients (4%). There was a positive correlation between MMR gene mutations and HR-associated gene mutations (p = 0.0072). Our findings might be useful in selection of ovarian cancer patients that should be treated with PARP inhibitors.

Higher Rates of t(11;18) in Chinese Patients with Transformed Type of MALT Lymphoma Suggest Novel Pathways for Progression of the Disease.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2621-2621
Author(s):  
Xiao-Yan Ke ◽  
Jing Wang ◽  
Ling-Zhi Zhao ◽  
Zi-Fen Gao ◽  
Fei Dong ◽  
...  
Keyword(s):  
Malt Lymphoma ◽  
B Cell Lymphoma ◽  
Chromosome Translocation ◽  
Chinese Patients ◽  
Low Grade ◽  
Fixed Tissue ◽  
Detection Rates ◽  
Nuclear Expression ◽  
H Pylori ◽  
Selection Of

Abstract Previous reports suggest that the prevalence and potential etiological factors of some types of lymphoma in China may be different from that reported in other countries. Our previous work in analyzing cell origin of 53 diffuse large B-cell lymphoma (DLBCL) patients demonstrated that Chinese patients have higher Non GC (%) DLBCL than GC(%) origin compare with the reports from Western countries (PMID: 16202261). In this study, we continued our exploration on potential differences between Chinese patients with mucosa-associated lymphoid tissue (MALT) lymphoma and patients reported from other countries. Several evidences suggest that gastric MALT lymphoma acquired as a consequence of Helicobacter pylori (H. pylori) infection and 80–90% patients with no t(11;18) chromosome translocation achieved the complete remission (CR) after receiving antibiotics therapy to eradicate H. pylori. But the patients with MALT, who have the t(11;18) and the nuclear expression of BCL-10, are barely responsive to the antibiotic therapy. Therefore, detection of the expression of t(11; 18) and BCL-10 nuclear expression in the patients with MALT lymphoma is of clinical significance in selection of H. pylori eradication regimen, predicting the clinical progression, and assessing the prognoses of the disease. In this study, we detected the t(11;18) chromosome translocation in different stages of MALT lymphoma. We established a RT-PCR with a method of short-length amplification by modifying that reported in preparation of RNAs from the paraffin-fixed tissue followed by molecular analysis of the genotype of the patients with MALT lymphoma. We examined the expression of API2-MALT1 in a large cohort of patients with lymphomas including 100 MALT lymphomas and 83 DLBCL cases, and analyzed the differences in the detection rates of API2-MALT1 fusion transcripts and BCL-10 nuclear expression among different MALT location. Our results showed the five key findings, including higher detection rates of t(11;18) (21.13%) in Chinese patients with transformed MALT lymphoma, lower detection rates of t(11;18) (15.79%) in stomach MALT lymphoma, different organ localizations of MALT lymphoma in Chinese patients, higher nuclear expression rates of Bcl-10 in low grade MALT (51.72%), and lower response rates (50% CR, and 50% PR) to anti-H. pylori therapy, suggest novel pathways for low-grade MALT lymphoma to be progressed into transformed MALT lymphoma. This study also suggests that amplification of shorter length of PCR products from the paraffin-fixed tissues increases the sensitivity, which is significant in improving selection of therapeutic regimen and assessing the prognoses of disease. Also, in Chinese patients with MALT lymphoma, Bcl-10 nuclear expression may be independent of t(11;18) translocation, and may also play primary roles in MALT pathogenesis rather than “supporting roles” for t(11;18). Future international collaboration is needed to clarify that whether this new model fits patients with other ethnic backgrounds in addition to Chinese patients.

scholarly journals Cumulative Histologic Inflammation Predicts Colorectal Neoplasia in Ulcerative Colitis: A Validation Study

2020 ◽  
Author(s):  
Olivia V Yvellez ◽  
Victoria Rai ◽  
Philip H Sossenheimer ◽  
John Hart ◽  
Jerrold R Turner ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Colorectal Neoplasia ◽  
Low Grade ◽  
Inflammatory Index ◽  
Surveillance Interval ◽  
Matched Case ◽  
The Mean ◽  
The University ◽  
Selection Of ◽  
Inflammatory Burden

Abstract Background Chronic inflammation in ulcerative colitis (UC) is associated with the development of colorectal neoplasia (CRN). A group at St. Mark’s Hospital reported a novel cumulative inflammatory index that predicted the development of CRN in UC patients that we validated with an independent, well-described, matched, case-controlled cohort from the University of Chicago. Methods Cumulative inflammatory burden (CIB) was calculated by summing each histological inflammatory activity (HIA) score and multiplying it by the length of the surveillance interval. Persistency was defined by the number of surveillance episodes (with a severity score >2) divided by the total number of surveillance procedures. T tests compared the mean and maximum HIA scores, assessing mean and maximum severity, CIB, and persistency. Results Sixty-two UC patients (26 patients with CRN, 36 control patients without CRN) were analyzed. Fifty-five percent were men, mean disease duration was 20.6 years, and mean age at CRN diagnosis was 43.9. Of the CRN patients, 6 (23%) had colorectal cancer, 16 (62%) had low-grade dysplasia, and 4 (15%) had indefinite dysplasia. Using mean HIA scores, we found CIB to be statistically greater in CRN patients (P = 0.04). Using maximum HIA scores, we found CIB (P = 0.02), mean severity (P = 0.03), and persistency (P = 0.01) to be significantly greater in CRN patients. Maximum severity was numerically greater for mean and maximum HIA scores but did not reach significance. Conclusion Cumulative histologic inflammation is significantly associated with the development of CRN in UC patients. This suggests a management strategy of controlling inflammation to reduce the risk of CRN and may influence the selection of surveillance intervals.

Supercritical Fluids and Their Applications in Power Generation

2021 ◽  
pp. 566-599
Author(s):  
Huijuan Chen ◽  
Ricardo Vasquez Padilla ◽  
Saeb Besarati
Keyword(s):  
Power Generation ◽  
Supercritical Fluids ◽  
Waste Heat ◽  
Electrical Power ◽  
Rankine Cycle ◽  
Low Grade ◽  
Heat Sources ◽  
Working Fluids ◽  
Low Grade Heat ◽  
Selection Of

Supercritical fluids have been studied and used as the working fluids in power generation system for both high- and low-grade heat conversions. Low-grade heat sources, typically defined as below 300 ºC, are abundantly available as industrial waste heat, solar thermal, and geothermal, to name a few. However, they are under-exploited for power conversion because of the low conversion efficiency. Technologies that allow the efficient conversion of low-grade heat into mechanical or electrical power are very important to develop. First part of this chapter investigates the potential of supercritical Rankine cycles in the conversion of low-grade heat to power, while the second part discusses supercritical fluids used in higher grade heat conversion system. The selection of supercritical working fluids for a supercritical Rankine cycle is of key importance. This chapter discusses supercritical fluids fundamentals, selection of supercritical working fluids for different heat sources, and the current research, development, and commercial status of supercritical power generation systems.

scholarly journals Conversion of Low-Grade Heat from Multiple Streams in Methanol to Olefin (MTO) Process Based on Organic Rankine Cycle (ORC)

2020 ◽  
Vol 10 (10) ◽  
pp. 3617 ◽  
Author(s):  
Danchen Wei ◽  
Cheng Liu ◽  
Zhongfeng Geng
Keyword(s):  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Exergy Efficiency ◽  
Working Fluid ◽  
Low Grade ◽  
Maximum Output ◽  
Methanol To Olefin ◽  
Thermodynamic Performance ◽  
Selection Of ◽  
Mto Process

The organic rankine cycle (ORC) has been widely used to convert low-grade thermal energy to electricity. The selection of the cycle configuration, working fluid, and operating parameters is crucial for the economic profitability of the ORC system. In the methanol to olefin (MTO) process, multi-stream low-temperature waste heat has not been effectively utilized. The previous study mostly focused on the optimization of a single stream system and rarely considered the comprehensive optimization of multi-stream ORC systems which have multi-temperature heat sources. This paper proposes five kinds of system design schemes, and determines the optimal output work and the highest exergy efficiency through the selection of working fluid and optimization of system parameters. In addition, the influence of mixed working fluid on the thermodynamic performance of the system was also investigated. It is found that there is an optimal evaporation temperature due to the restriction of pinch temperature. At the optimal temperature the ORC system obtains the maximum net output power of 4.95 MW. The optimization results show that the working fluid R227EA selected from seven candidate working fluids shows the optimal thermodynamic performance in all the five design schemes, and obtains the maximum output work and exergy efficiency.

scholarly journals Impact of Occupational Exposures and Genetic Polymorphisms on Recurrence and Progression of Non-Muscle-Invasive Bladder Cancer

2018 ◽  
Vol 15 (8) ◽  
pp. 1563 ◽  
Author(s):  
Angela Carta ◽  
Sofia Pavanello ◽  
Giuseppe Mastrangelo ◽  
Ugo Fedeli ◽  
Cecilia Arici ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Occupational Exposure ◽  
Genetic Polymorphisms ◽  
Occupational Exposures ◽  
Smoking History ◽  
Invasive Bladder Cancer ◽  
Low Grade ◽  
Muscle Invasive Bladder Cancer ◽  
Muscle Invasive ◽  
Selection Of

Introduction: Additional or better markers are needed to guide the clinical monitoring of patients with non-muscle-invasive bladder cancer (NMIBC). Aim: To investigate the influence of occupational exposures and genetic polymorphisms on recurrence and progression of NMIBC. Methods: The study includes 160 NMIBC patients. We collected on questionnaire information on demographic variables, lifetime smoking history, lifetime history of occupational exposure to aromatic amines and polycyclic aromatic hydrocarbons. Genetic polymorphism (glutathione S-transferase M1; T1; P1 (GSTM1; GSTT1; GSTP1); N-acetyltransferase 1; 2 (NAT1; NAT2); cytochrome P450 1B1 (CYP1B1); sulfotransferase 1A1 (SULT1A1); myeloperoxidase (MPO); catechol-O-methyltransferase (COMT); manganese superoxide dismutase (MnSOD); NAD(P)H:quinone oxidoreductase (NQO1); X-ray repair cross-complementing group 1; 3 (XRCC1; XRCC3) and xeroderma pigmentosum complementation group (XPD)) was assessed in peripheral blood lymphocytes. DNA adducts were evaluated by 32P-postlabeling. Predictors of recurrence (histological confirmation of a newly found bladder tumor) and progression (transition of tumor from low-grade to high-grade and/or increase in TNM stage) were identified by multivariate Cox proportional hazard regression with stepwise backward selection of independent variables. Hazard ratios (HR) with 95% confidence interval (95%CI) and two-tail probability of error (p-value) were estimated. Results: The risk of BC progression decreased with the homozygous genotype “ValVal” of both COMT and MnSOD (HR = 0.195; 95%CI = 0.060 to 0.623; p = 0.006). The results on BC recurrence were of borderline significance. No occupational exposure influenced recurrence or progression. Conclusion: Our results are supported by experimental evidence of a plausible mechanism between cause (ValVal genotype of both MnSOD and COMT) and effect (decreased progression of tumor in NMIBC patients). The genetic polymorphisms associated with better prognosis may be used in clinic to guide selection of treatment for patients initially diagnosed with NMIBC. However, external validation studies are required.

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