Characterization of waste. Guidance on selection and application of screening methods

2013 ◽  
Keyword(s):  
2020 ◽  
Vol 9 (10) ◽  
pp. 3313 ◽  
Author(s):  
Hemant Goyal ◽  
Rupinder Mann ◽  
Zainab Gandhi ◽  
Abhilash Perisetti ◽  
Aman Ali ◽  
...  

Globally, colorectal cancer is the third most diagnosed malignancy. It causes significant mortality and morbidity, which can be reduced by early diagnosis with an effective screening test. Integrating artificial intelligence (AI) and computer-aided detection (CAD) with screening methods has shown promising colorectal cancer screening results. AI could provide a “second look” for endoscopists to decrease the rate of missed polyps during a colonoscopy. It can also improve detection and characterization of polyps by integration with colonoscopy and various advanced endoscopic modalities such as magnifying narrow-band imaging, endocytoscopy, confocal endomicroscopy, laser-induced fluorescence spectroscopy, and magnifying chromoendoscopy. This descriptive review discusses various AI and CAD applications in colorectal cancer screening, polyp detection, and characterization.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Eva Petit ◽  
Monique Berger ◽  
Laurent Camborde ◽  
Veronica Vallejo ◽  
Jean Daydé ◽  
...  

Abstract Glycosylation is a key modification that contributes to determine bioactivity and bioavailability of plant natural products, including that of terpenoids and steviol glycosides (SVglys). It is mediated by uridine-diphosphate glycosyltransferases (UGTs), that achieve their activity by transferring sugars on small molecules. Thus, the diversity of SVglys is due to the number, the position and the nature of glycosylations on the hydroxyl groups in C-13 and C-19 of steviol. Despite the intense sweetener property of SVglys and the numerous studies conducted, the SVglys biosynthetic pathway remains largely unknown. More than 60 SVglys and 68 putative UGTs have been identified in Stevia rebaudiana. This study aims to provide methods to characterize UGTs putatively involved in SVglys biosynthesis. After agroinfiltration-based transient gene expression in Nicotiana benthamiana, functionality of the recombinant UGT can be tested simply and directly in plants expressing it or from a crude extract. The combined use of binary vectors from pGWBs series to produce expression vectors containing the stevia's UGT, enables functionality testing with many substrates as well as other applications for further analysis, including subcellular localization.


1983 ◽  
Vol 15 (6-7) ◽  
pp. 1-11 ◽  
Author(s):  
Per-Edvin Persson

The significance of off-flavours in water and fisheries management is briefly discussed, as are guidelines for future research. In order to elucidate the sources and causes of off-flavours in natural waters, an integration of sensory, chemical and biological research is needed. Sensory characterization of off-flavours often involves taste and odour threshold measurements. Current techniques at water works are critically discussed. The need for a more comprehensive approach, where sensory response is related to stimulus intensity over a large range of magnitudes, is stressed. The use of consumer panels in sensory assessment of water quality is advocated. Sensory methods are useful screening methods. Chemical analyses should be related to the sensory characteristics of the compounds analyzed. Recent research on biogenic off-flavours in natural waters have indicated that they are more, complex than originally conceived. Criteria for establishing the odour production by organisms are presented. Compilations of scientifically proved taste and odour producing algae and micro-organisms may be useful, but more research is needed on the reasons for variability of their odour production. The development of relevant abatement techniques depends on a more complete understanding of the etiology of off-flavours in natural waters.


2021 ◽  
Vol 37 (2) ◽  
pp. 165-176
Author(s):  
W.C John ◽  
I.O Ogbonna ◽  
G.M Gberikon ◽  
C.C Iheukwumere

Biosurfactants synthesized by microorganisms are chemically diverse and have gained interest industrially due to their surface and interfacial tensions-reducing activities. In this study Bacillus species from contaminated soils were screened and characterized for biosurfactant production. The study was carried out at the Microbiology Laboratory, Federal University of Agriculture Makurdi, Nigeria. The Bacillus species were isolated from kerosene shops, palm oil shops, nearby restaurants, mechanic workshops and abattoir effluents- contaminated soil samples collected from Makurdi metropolis. The Bacillus spp. were screened for biosurfactants production potentials using various screening methods (oil spreading, beta haemolysis, drop collapse and emulsification index). Specific primers were used to amplify the srfAA (surfactin gene) gene in the Bacillus isolates and the nucleotide sequences were determined at Inqaba Biotec, South Africa. The screening results were statistically analysed using analysis of variance (ANOVA) at 95 % confidence level. Isolate RT7(4)B exhibited the ability to produce biosurfactant, as well as the highest emulsification index (E24) of 73.25 % while isolate PO7(3)C gave the highest oil displacement of 6.77 mm. The supernatant obtained from isolate RT7(4)B showed reduction in surface tension of up to 30.26 mN/m. The isolates gave positive results for biosurfactant production when subjected to drop collapse and Beta haemolytic tests. The Polymerase chain reaction (PCR) results revealed amplifications of srfAA gene from 7 isolates. Based on these findings, the isolates used in this study can be utilized for biosurfactant production, and can also be useful for bioremediation and industrial biotechnology applications. Keywords: Biosurfactants; emulsification index; Bacillus; surface tension; Drop collapse


2003 ◽  
Vol 80 (3) ◽  
pp. 274-280 ◽  
Author(s):  
Jesper Pram Nielsen ◽  
Dorthe Kjær Pedersen ◽  
Lars Munck

2020 ◽  
Vol 77 (21) ◽  
pp. 4209-4222
Author(s):  
Farah Kobaisi ◽  
Nour Fayyad ◽  
Eric Sulpice ◽  
Bassam Badran ◽  
Hussein Fayyad-Kazan ◽  
...  

Abstract Inherited or acquired mutations can lead to pathological outcomes. However, in a process defined as synthetic rescue, phenotypic outcome created by primary mutation is alleviated by suppressor mutations. An exhaustive characterization of these mutations in humans is extremely valuable to better comprehend why patients carrying the same detrimental mutation exhibit different pathological outcomes or different responses to treatment. Here, we first review all known suppressor mutations’ mechanisms characterized by genetic screens on model species like yeast or flies. However, human suppressor mutations are scarce, despite some being discovered based on orthologue genes. Because of recent advances in high-throughput screening, developing an inventory of human suppressor mutations for pathological processes seems achievable. In addition, we review several screening methods for suppressor mutations in cultured human cells through knock-out, knock-down or random mutagenesis screens on large scale. We provide examples of studies published over the past years that opened new therapeutic avenues, particularly in oncology.


2010 ◽  
Vol 25 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Zhebo Chen ◽  
Thomas F. Jaramillo ◽  
Todd G. Deutsch ◽  
Alan Kleiman-Shwarsctein ◽  
Arnold J. Forman ◽  
...  

Photoelectrochemical (PEC) water splitting for hydrogen production is a promising technology that uses sunlight and water to produce renewable hydrogen with oxygen as a by-product. In the expanding field of PEC hydrogen production, the use of standardized screening methods and reporting has emerged as a necessity. This article is intended to provide guidance on key practices in characterization of PEC materials and proper reporting of efficiencies. Presented here are the definitions of various efficiency values that pertain to PEC, with an emphasis on the importance of solar-to-hydrogen efficiency, as well as a flow chart with standard procedures for PEC characterization techniques for planar photoelectrode materials (i.e., not suspensions of particles) with a focus on single band gap absorbers. These guidelines serve as a foundation and prelude to a much more complete and in-depth discussion of PEC techniques and procedures presented elsewhere.


1998 ◽  
Vol 36 (4) ◽  
pp. 1020-1027 ◽  
Author(s):  
Fred C. Tenover ◽  
Michael V. Lancaster ◽  
Bertha C. Hill ◽  
Christine D. Steward ◽  
Sheila A. Stocker ◽  
...  

During the last several years a series of staphylococcal isolates that demonstrated reduced susceptibility to vancomycin or other glycopeptides have been reported. We selected 12 isolates of staphylococci for which the vancomycin MICs were ≥4 μg/ml or for which the teicoplanin MICs were ≥8 μg/ml and 24 control strains for which the vancomycin MICs were ≤2 μg/ml or for which the teicoplanin MICs were ≤4 μg/ml to determine the ability of commercial susceptibility testing procedures and vancomycin agar screening methods to detect isolates with reduced glycopeptide susceptibility. By PCR analysis, none of the isolates with decreased glycopeptide susceptibility contained known vancomycin resistance genes. Broth microdilution tests held a full 24 h were best at detecting strains with reduced glycopeptide susceptibility. Disk diffusion did not differentiate the strains inhibited by 8 μg of vancomycin per ml from more susceptible isolates. Most of the isolates with reduced glycopeptide susceptibility were recognized by MicroScan conventional panels and Etest vancomycin strips. Sensititre panels read visually were more variable, although with some of the panels MICs of 8 μg/ml were noted for these isolates. Vitek results were 4 μg/ml for all strains for which the vancomycin MICs were ≥4 μg/ml. Vancomycin MICs on Rapid MicroScan panels were not predictive, giving MICs of either ≤2 or ≥16 μg/ml for these isolates. Commercial brain heart infusion vancomycin agar screening plates containing 6 μg of vancomycin per ml consistently differentiated those strains inhibited by 8 μg/ml from more susceptible strains. Vancomycin-containing media prepared in-house showed occasional growth of susceptible strains, Staphylococcus aureus ATCC 29213, and on occasion, Enterococcus faecalis ATCC 29212. Thus, strains of staphylococci with reduced susceptibility to glycopeptides, such as vancomycin, are best detected in the laboratory by nonautomated quantitative tests incubated for a full 24 h. Furthermore, it appears that commercial vancomycin agar screening plates can be used to detect these isolates.


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