Journal articles: 'SENSITIVE QAC'

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Grillitsch, B., O. Gans, N. Kreuzinger, S. Scharf, M. Uhl, and M. Fuerhacker. "Environmental risk assessment for quaternary ammonium compounds: a case study from Austria." Water Science and Technology 54, no. 11-12 (December 1, 2006): 111–18. http://dx.doi.org/10.2166/wst.2006.840.

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Quaternary ammonium compounds (QAC) are widely used as disinfectants, biocides, and detergents, among a variety of other applications. The cationic surface-activity of QAC determines their potential to act as a biocide on both target and non-target organisms. This study aims to provide a broad-based environmental risk characterization and evaluation for selected QAC with particular focus on the situation in Austrian rivers. A modular study design was employed involving environmental exposure characterization, QAC fate and effect analysis in wastewater, ecotoxicological effect characterization, and environmental risk evaluation. A wide array of Austrian surface waters and wastewater effluents were screened for the selected key compounds, benzalkonium chlorides and dialkyldimethylammonium chlorides with different C-chain lengths. Ecotoxicological effect characterization was based on both microbiotests for a set of representative aquatic organisms and a literature review. For risk evaluation, the PEC/PNEC ratio was above 1 for some rivers. Notably, small rivers with a high particulate matter were contaminated with QAC in the case of high water incidents. Hence, for the Austrian sites studied, a QAC-derived risk to sensitive aquatic non-target organisms could not be excluded.

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Antosik, Adrian Krzysztof, Karolina Mozelewska, Magdalena Zdanowicz, Konrad Gziut, and Piotr Miądlicki. "Organophilized Montmorillonites as Fillers for Silicone Pressure-Sensitive Adhesives." Materials 16, no. 3 (January 19, 2023): 950. http://dx.doi.org/10.3390/ma16030950.

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In the presented work, organophilized montmorillonites (OMMT) with selected quaternary ammonium compounds (QAC) with different chemical structure ((trioctylmethylammonium chloride—A336, dimethyloctadecyl[3-trimethoxysilyl)propyl]ammonium chloride—D, cetyltrimethylammonium bromide—CTAB, 2-methacryloxyethyltrimethylammonium chloride—MOA) were obtained and used as fillers for physically modified silicone pressure-sensitive adhesives (Si-PSA). Before OMMT addition into Si-PSA matrix, they were analyzed via TGA and XRD techniques. Type of chemical structure of QAC affected d-spacing of OMMT. New self-adhesive materials were obtained based on prepared Si-PSA compositions by adding the obtained fillers to the polymer matrix. New tapes exhibit a good level of useful properties as adhesion, cohesion, and tack—the values did not change or slightly decreased; in addition, the tapes with addition of OMMT showed high thermal resistance reaching the measuring limit of the test equipment—to 225 °C.

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Jiang, Danyang, Honghui Chen, and Fei Cai. "Exploiting Query’s Temporal Patterns for Query Autocompletion." Mathematical Problems in Engineering 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/7490879.

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Query autocompletion (QAC) is a common interactive feature of web search engines. It aims at assisting users to formulate queries and avoiding spelling mistakes by presenting them with a list of query completions as soon as they start typing in the search box. Existing QAC models mostly rank the query completions by their past popularity collected in the query logs. For some queries, their popularity exhibits relatively stable or periodic behavior while others may experience a sudden rise in their query popularity. Current time-sensitive QAC models focus on either periodicity or recency and are unable to respond swiftly to such sudden rise, resulting in a less optimal QAC performance. In this paper, we propose a hybrid QAC model that considers two temporal patterns of query’s popularity, that is, periodicity and burst trend. In detail, we first employ the Discrete Fourier Transform (DFT) to identify the periodicity of a query’s popularity, by which we forecast its future popularity. Then the burst trend of query’s popularity is detected and incorporated into the hybrid model with its cyclic behavior. Extensive experiments on a large, real-world query log dataset infer that modeling the temporal patterns of query popularity in the form of its periodicity and its burst trend can significantly improve the effectiveness of ranking query completions.

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Sidhu, Maan Singh, Even Heir, Truls Leegaard, Karianne Wiger, and Askild Holck. "Frequency of Disinfectant Resistance Genes and Genetic Linkage with β-Lactamase Transposon Tn552 among Clinical Staphylococci." Antimicrobial Agents and Chemotherapy 46, no. 9 (September 2002): 2797–803. http://dx.doi.org/10.1128/aac.46.9.2797-2803.2002.

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ABSTRACT A total of 61 strains of Staphylococcus aureus and 177 coagulase-negative staphylococcal strains were isolated from the blood of patients with bloodstream infections and from the skin of both children under cancer treatment and human immunodeficiency virus-positive patients. The MIC analyses revealed that 118 isolates (50%) were resistant to quaternary ammonium compound-based disinfectant benzalkonium chloride (BC). The frequencies of resistance to a range of antibiotics were significantly higher among BC-resistant staphylococci than among BC-sensitive staphylococci. Of 78 BC-resistant staphylococcal isolates, plasmid DNA from 65 (83%), 2 (3%), 43 (55%), and 15 (19%) isolates hybridized to qacA or -B (qacA/B), qacC, blaZ, and tetK probes, respectively. The qacA/B and blaZ probes hybridized to the same plasmid in 19 (24%) staphylococcal strains. The plasmids harboring both qacA/B and blaZ genes varied from approximately 20 to 40 kb. The Staphylococcus epidermidis Fol62 isolate, harboring multiresistance plasmid pMS62, contained qacA/B and blaZ together with tetK. Molecular and genetic studies indicated different structural arrangements of blaZ and qacA/B, including variable intergenic distances and transcriptional directions of the two genes on the same plasmid within the strains. The different organizations may be due to the presence of various genetic elements involved in cointegration, recombination, and rearrangements. These results indicate that qac resistance genes are common and that linkage between resistance to disinfectants and penicillin resistance occurs frequently in clinical isolates in Norway. Moreover, the higher frequency of antibiotic resistance among BC-resistant strains indicates that the presence of either resistance determinant selects for the other during antimicrobial therapy and disinfection in hospitals.

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He, Gui-Xin, Michael Landry, Huizhong Chen, Conner Thorpe, Dennis Walsh, Manuel F. Varela, and Hongmiao Pan. "Detection of benzalkonium chloride resistance in community environmental isolates of staphylococci." Journal of Medical Microbiology 63, no. 5 (May 1, 2014): 735–41. http://dx.doi.org/10.1099/jmm.0.073072-0.

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We isolated a total of 653 strains from 64 community environmental samples in Massachusetts, USA. Among these isolates, 9.65 % (63 strains) were benzalkonium chloride (BC)-resistant staphylococci. All BC-resistant strains were collected from surfaces upon which antibacterial wipes or antibacterial sprays containing 0.02–0.12 % BC had frequently been used in the fitness centres. However, isolates from surfaces upon which antibacterial wipes or antibacterial sprays had not been used were all sensitive to BC. All BC-resistant strains were also resistant to erythromycin, penicillin and ampicillin. In addition, 51 strains showed resistance to cetyltrimethylammonium bromide (CTAB), 15 strains showed resistance to chloramphenicol, 12 strains showed resistance to ciprofloxacin and four strains showed resistance to meticillin. Resistance gene analysis demonstrated that 41 strains contained qacA/B, 30 strains had qacC, 25 strains contained qacG, 16 strains had qacH and eight strains contained qacJ. These data indicate that application of BC is associated with environmental staphylococcal antimicrobial resistance.

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Ibrahim, Waleed A., Sherif A. Marouf, Ahmed M. Erfan, Soad A. Nasef, and Jakeen K. El Jakee. "The occurrence of disinfectant and antibiotic-resistant genes in Escherichia coli isolated from chickens in Egypt." Veterinary World 12, no. 1 (January 2019): 141–45. http://dx.doi.org/10.14202/vetworld.2019.141-145.

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Aim: This work aimed to determine the occurrence of antibiotic and disinfectant resistance genes in Escherichia coli isolated from chickens in Egypt. Materials and Methods: Organs (liver, lung, heart, yolk sac, and bone marrow) of 1500 chicken samples were collected from diseased chickens suffered from colibacillosis with PM findings as CRD, diarrhea and omphalitis from different governorates of Egypt as: Giza, EL-Bahira, Fayoum, El-Dakahlia, El-Ismalia, and El-Sharkia during 2015-2016. These samples were labeled and transported immediately on ice to the Reference laboratory for quality control on poultry production (RLQP). The samples were cultured onto MacConkey agar and Eosin Methylene Blue Agar. Isolation and identification of the E. coli were performed based on morphology, cultural, staining, and biochemical properties. Antimicrobial resistance test was carried out using disk diffusion method. The PCR employing tetA, qacED1 and qacA/B were carried out for detection of these genes in isolated E.coli. Results: The prevalence of E. coli in chicken was 34%. Predominant serotypes of E. coli which serologically identified were O128, O111, O44, O158, and O2. Antibiotic susceptibility test of E. coli revealed that 100% of isolates were resistant to ampicillin, erythromycin, and sulfamethoxazole-trimethoprim, while 73.53% and 38.23% of them were sensitive for colistin sulfate and levofloxacin, respectively. Antibiotic resistance genes as tetA gene were tested for isolated E. coli and detected by incidence rate of 91.18%. qac resistance genes resembling as qacED1 and qacA/B genes were detected in isolated E. coli 70.6% and 14.7%, respectively. Conclusion: E. coli isolated from chickens in Egypt was carried qac and antibiotic-resistant genes that affect the poultry industry.

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Biswas, Saswati, and Indranil Biswas. "Role of VltAB, an ABC Transporter Complex, in Viologen Tolerance inStreptococcus mutans." Antimicrobial Agents and Chemotherapy 55, no. 4 (January 31, 2011): 1460–69. http://dx.doi.org/10.1128/aac.01094-10.

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ABSTRACTStreptococcus mutans, a Gram-positive organism, is the primary causative agent in the formation of dental caries in humans. To persist in the oral cavity,S. mutansmust be able to tolerate rapid environmental fluctuations and exposure to various toxic chemicals. However, the mechanisms underlying the ability of this cariogenic pathogen to survive and proliferate under harsh environmental conditions remain largely unknown. Here, we wanted to understand the mechanisms by whichS. mutanswithstands exposure to methyl viologen (MV), a quaternary ammonium compound (QAC) that generates superoxide radicals in the cell. To elucidate the essential genes for MV tolerance, screening of ∼3,500 mutants generated by ISS1mutagenesis, revealed 15 MV-sensitive mutants. Among them, five and four independent insertions had occurred in SMU.905 and SMU.906 genes, respectively. These two genes are appeared to be organized in an operon and encode a putative ABC transporter complex; we designated the genes asvltAandvltB, forviologentransporter. To verify our results,vltAwas deleted by using an antibiotic resistance marker; the mutant was just as sensitive to MV as the ISS1insertion mutants. Furthermore,vltAandvltBmutants were also sensitive to other viologen compounds such as benzyl and ethyl viologens. Complementation assays were also carried out to confirm the role of VltA and VltB in viologen tolerance. Sensitivity to various drugs, including a wide range of QACs, was evaluated. It appears that a functional VltA is also required for full resistance toward acriflavin, ethidium bromide, and safranin; all are well-known QACs. These results indicate that VltA/B constitute a heterodimeric multidrug efflux pump of the ABC family. BLAST-P analysis suggests that homologs of VltA/B are widely present in streptococci, enterococci, and other important Gram-positive pathogens.

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Hanczvikkel, Adrienn, András Víg, and Ákos Tóth. "Survival capability of healthcare-associated, multidrug-resistant bacteria on untreated and on antimicrobial textiles." Journal of Industrial Textiles 48, no. 7 (January 24, 2018): 1113–35. http://dx.doi.org/10.1177/1528083718754901.

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Healthcare-associated infections are of global concern, and textiles can contribute to the transmission of pathogens. In this study, we examined quantitatively the survival capability of 60 multidrug-resistant bacterial strains from four species ( Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus and Enterococcus faecium) on untreated cotton textile in clinically relevant incubation periods. We determined the antibacterial efficiency of textiles treated either with quaternary ammonium compound (QAC)-containing Sanitized T99-19 liquid (50 m/m% Dimethyltetradecyl (3-(trimethoxysilyl)propyl) ammonium-chloride) or with silver salt-containing Sanitized T27-22 Silver liquid (2 m/m% AgCl and 8 m/m% TiO2) as well. Finally, we compared the results of the healthcare-associated, multidrug-resistant strains and antibiotic-sensitive, quality control standard strains (ATCC 25922, ATCC 11105 Escherichia coli, and ATCC 25923, ATCC 6538 Staphylococcus aureus) often used in antimicrobial efficiency tests. The results revealed that all investigated multidrug-resistant bacteria are able to survive on untreated cotton textile and pose health risk in hospitals. During one day the T27-22-Silver-treated textile was able to eliminate most of the Gram-positive pathogens, reducing the risk of cross-contamination, but none of the examined agents destroyed the multidrug-resistant, Gram-negative isolates. The antibiotic-susceptible and the multidrug-resistant Staphylococcus aureus strains had similar survival capability and biocide-tolerance, while the risk of infections caused by multidrug-resistant, Gram-negative pathogens could be extremely underestimated using only ATCC Escherichia coli standard strains. Our results also draw attention to the careful evaluation of antimicrobial efficiency tests and indicate that a significant reduction of bacterial count does not necessarily mean significant antibacterial efficiency that would be suitable to avoid infections.

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Soloski, M. J., A. Lattimore, D. Hereld, J. L. Krakow, M. G. Low, and G. Einhorn. "Further characterization of the membrane anchor found on the tissue-specific class I molecule Qa2." Journal of Immunology 140, no. 11 (June 1, 1988): 3858–66. http://dx.doi.org/10.4049/jimmunol.140.11.3858.

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Abstract Previous studies have determined that various Qa2 serologic determinants can be removed from the surface of spleen cells by treatment with a phospholipase C. Our studies have determined that the class I molecule Qa2, expressed on the surface of spleen cells and activated T cells, behaves as an integral membrane protein based on its ability to associate with detergent micelles. Studies utilizing two purified phospholipase C have revealed that although most (90 to 95%) of the Qa2 molecules expressed on the surface of resting spleen cells are released as intact 40-kDa polypeptides associated with beta 2-microglobulin, activated T cells contain a major cell subpopulation expressing lipase-resistant Qa2 molecules. Flow cytometric analysis revealed that L3T4+-activated T cells expressed lipase-sensitive Qa2 molecules, whereas Lyt-2+ cells express lipase-resistant forms of the Qa2 molecule. The relationship between the secreted form of the Qa2 molecule and the lipase-generated soluble Qa2 molecule was investigated. Based on SDS-PAGE analysis, the secreted Qa2 molecules has a Mr of 39 kDa whereas the cell surface form released from either resting spleen or activated T cells by phosphatidylinositol-specific phospholipase C has a Mr of approximately equal to 40 kDa. Furthermore, the secreted Qa2 molecule lacks an epitope, cross-reacting determinant, often present on lipase-solubilized cell surface molecules. Thus, based on serologic and biochemical criteria, the soluble Qa2 molecules generated by an exogenous phospholipase C and the secreted Qa2 molecule are structurally distinct.

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Bardasheva, Alevtina, Artem Tikunov, Yuliya Kozlova, Elena Zhirakovskaia, Valeriya Fedorets, Natalya Fomenko, Tatyana Kalymbetova, et al. "Antibiotic Resistance and Pathogenomics of Staphylococci Circulating in Novosibirsk, Russia." Microorganisms 9, no. 12 (November 30, 2021): 2487. http://dx.doi.org/10.3390/microorganisms9122487.

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A total of 394 strains of staphylococci found in humans and pets in Novosibirsk, Siberian Russia, were characterized in terms of antibiotic resistance and corresponding genes. Two coagulase-positive and 17 coagulase-negative species were identified. The majority of isolates, with the exception of S. haemolyticus and hospital S. epidermidis isolates, were sensitive to most of the tested antibiotics, and isolates from pets displayed the lowest level of resistance. Nevertheless, methicillin-resistant (MRS) and/or multidrug-resistant (MDR) isolates were found in all prevailed species, including coagulase-negative. A set of genes corresponding to the detected resistance was identified: mecA (beta-lactam resistance), aac(6′)-Ie-aph(2″)-Ia, aph(3′)-IIIa, ant(4′)-Ia (aminoglycoside-modifying enzymes), ermA/ermC, and msrA (macrolide resistance). Complete genome analysis for ten MDR S. epidermidis and five MDR S. haemolyticus isolates revealed additional antibiotic resistance genes mphC, qacA/qacB, norA, dfrC/dfrG, lnuA, BseSR, and fosB. NorA, dfrC, and fosB were present in all S. epidermidis genomes, whereas mphC and msrA were identified in all S. haemolyticus ones. All investigated MDR S. epidermidis and four of five S. haemolyticus strains were moderate or strong biofilm producers, whereas multiple genes responsible for this function and for virulence and pathogenicity were identified mostly in S. epidermidis, but were less frequently represented in S. haemolyticus.

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Crabb, Charlene. "More sensitive assay to detect drug-resistant HIV." AIDS 21, no. 18 (November 2007): N3. http://dx.doi.org/10.1097/qad.0b013e3282f20d0c.

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Molina-García, Lucía, M. Luisa Fernández-de Córdova, and Antonio Ruiz-Medina. "Sensitive Determination of Indomethacin in Pharmaceuticals and Urine by Sequential Injection Analysis and Optosensing." Journal of AOAC INTERNATIONAL 93, no. 5 (September 1, 2010): 1443–49. http://dx.doi.org/10.1093/jaoac/93.5.1443.

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Abstract A selective and sensitive method based on coupling of sequential injection analysis (SIA) and optosensing was developed and applied to the determination of indomethacin in pharmaceutical and urinary samples. After alkaline hydrolysis, the fluorescent product generated from indomethacin is inserted in the flow system, transitorily retained on an active solid support (Sephadex QAE A-25) filling the flowcell, and monitored at 283/371 nm (λex/λem). The system was calibrated for two sample volumes, 100 and 1000 µL. It showed a linear dynamic range of 0.56.5 ng/mL, with an LOD of 0.15 ng/mL and an RSD of 3.9% (n = 10) when the highest sample volume was used. The proposed fluorometric SIA optosensor was applied to the determination of indomethacin in both pharmaceuticals and urine samples, and satisfactory results were obtained.

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Sheng, Ren, and Xiaoran Zhu. "Tool Wear Assessment Approach Based on the Neighborhood Rough Set Model and Nearest Neighbor Model." Shock and Vibration 2020 (December 17, 2020): 1–15. http://dx.doi.org/10.1155/2020/8876187.

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In order to assess the degree of wear of tool for milling process quantitatively, a new assessment approach is proposed. Firstly, making full use of the neighbor information, two sensitive features are selected by using the neighborhood rough set model, and then, boundary curves are established by using the nearest neighbor model with noncounter data in two dimension spaces. Secondly, the intersection area or expanding area is used to describe the difference between two boundary models because the intersection area or expanding area can consider the effect of distance and angle simultaneously in two dimension spaces. Thirdly, after determining a baseline state, a new quantitative assessment indicator (QAI) can be calculated based on the intersection area or expanding area. The QAI can directly measure the difference between the model of baseline state and the model of unknown state and indirectly measure the degree of wear of tool. Finally, the effectiveness of the assessment approach is proven by using the Milling Dataset which was provided by the NASA Ames Research Center.

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Nash, Denis, Yussef Bennani, Chitra Ramaswamy, and Lucia Torian. "Estimates of HIV Incidence Among Persons Testing for HIV Using the Sensitive/Less Sensitive Enzyme Immunoassy, New York City, 2001." JAIDS Journal of Acquired Immune Deficiency Syndromes 39, no. 1 (May 2005): 102–11. http://dx.doi.org/10.1097/01.qai.0000144446.52141.4c.

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Williams, Emily C., Kathleen A. McGinnis, Janet P. Tate, Theresa E. Matson, Anna D. Rubinsky, Jennifer F. Bobb, Gwen T. Lapham, et al. "HIV Disease Severity Is Sensitive to Temporal Changes in Alcohol Use." JAIDS Journal of Acquired Immune Deficiency Syndromes 81, no. 4 (August 2019): 448–55. http://dx.doi.org/10.1097/qai.0000000000002049.

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Nabatiyan, Arman, Michael A. Baumann, Zaheer Parpia, and David Kelso. "A Lateral Flow-Based Ultra-Sensitive p24 HIV Assay Utilizing Fluorescent Microparticles." JAIDS Journal of Acquired Immune Deficiency Syndromes 53, no. 1 (January 2010): 55–61. http://dx.doi.org/10.1097/qai.0b013e3181c4b9d5.

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Kawamoto, Manabu, Akiko Fujiwara, Shin-ichi Kuno, and Ikuo Yasumasu. "Changes in the activities of protein phosphatase type 1 and type 2A in sea urchin embryos during early development." Zygote 8, S1 (December 1999): S68—S69. http://dx.doi.org/10.1017/s0967199400130370.

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Serine/threonine protein phosphatases expected to participate in the process of signal transduction, cell movement such as cell division and gene expression (Kinoshita et al., 1990; Healy et al., 1991; Mayer-Jaekel et al., 1993; Mumby & Walter, 1993), are classified into type 1 (PP1), type 2A (PP2A), type 2B and type 2C in mammalian cells. PP1 and PP2A are known to be strongly inhibited by okadaic acid (OA) (Tachibana et al., 1981; Bialojan Takai, 1988), a polyether fatty acid isolated from the marine sponge Halicondria okadai (Haystead et al., 1989). OA is also known to inhibit PP2A at lower concentrations than that to block PP1 in mammalian cells, but does not inhibit the activities of other phosphatase species (Ishihara et al., 1989).The p-nitrophenyl phosphate (pNPP) splitting activity in the extract obtained from eggs of the sea urchin Hemicentrotus pulcherrimus was found to be inhibited by OA and calyculin A (CLA), potent inhibitors of PP1 and PP2A. OA-sensitive phosphatases are known to catalyse pNPP splitting (Takai & Mieskes, 1991), in the same manner as other OA-insensitive phosphatases.Four peaks of the pNPP splitting activity were obtained by QAE-Toyopearl chromatography in the extract of sea urchin eggs. In two of these four peaks, pNPP splitting reactions were strongly inhibited by OA and CLA at quite low concentration. High sensitivities of the pNPP splitting reaction to OA and CLA in these two peaks suggest that pNPP splitting results from the reaction catalysed by PP2A. The molecular masses of proteins exhibiting OA-sensitive pNPP splitting activities in these two peaks were found to be about 160 kDa by Superdex 200HR, and were similar to that of mammalian PP2A trimeric holoenzyme. By immunoblot analyses with anti-human PP2A catalytic subunit antibody, an immunoreactive 36 kDa protein was found by SDS-PAGE in a peak of OA-sensitive pNPP splitting activity obtained by QAE-Toyopearl chromatography. Sea urchin eggs have at least two PP2A-like enzymes with similar molecular masses to that of mammalian PP2A, and one of them contains human-type catalytic subunit.

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Umeki, T., O. Tadanaga, M. Asobe, Y. Miyamoto, and H. Takenouchi. "First demonstration of high-order QAM signal amplification in PPLN-based phase sensitive amplifier." Optics Express 22, no. 3 (January 29, 2014): 2473. http://dx.doi.org/10.1364/oe.22.002473.

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Li, Jin-fen, Laurie Linley, Richard Kline, Rebecca Ziebell, Walid Heneine, and Jeffrey A. Johnson. "Sensitive sentinel mutation screening reveals differential underestimation of transmitted HIV drug resistance among demographic groups." AIDS 30, no. 9 (June 2016): 1439–45. http://dx.doi.org/10.1097/qad.0000000000001099.

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Kikuchi, N., and S. Sasaki. "Highly Sensitive Optical Multilevel Transmission of Arbitrary Quadrature-Amplitude Modulation (QAM) Signals With Direct Detection." Journal of Lightwave Technology 28, no. 1 (January 2010): 123–30. http://dx.doi.org/10.1109/jlt.2009.2035827.

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Allers, Kristina, Stefanie A. Knoepfel, Pia Rauch, Hauke Walter, Milos Opravil, Marek Fischer, Huldrych F. G??nthard, and Karin J. Metzner. "Persistence of Lamivudine-Sensitive HIV-1 Quasispecies in the Presence of Lamivudine In Vitro and In Vivo." JAIDS Journal of Acquired Immune Deficiency Syndromes 44, no. 4 (April 2007): 377–85. http://dx.doi.org/10.1097/qai.0b013e31803104c0.

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Mei, Joanne V., Meredith Kennedy, Laurie Linley, Debra Hanson, Jarad Schiffer, Steven Ethridge, and Bernard Branson. "Standardization and Monitoring of Laboratory Performance and Quality Assurance by Use of the Less-Sensitive HIV Incidence Assay." JAIDS Journal of Acquired Immune Deficiency Syndromes 58, no. 5 (December 2011): 482–88. http://dx.doi.org/10.1097/qai.0b013e318230dd77.

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Abbate, I., G. Rozera, C. Vlassi, B. Bartolini, A. Bruselles, E. Giombini, G. DʼOffizi, P. Narciso, and M. R. Capobianchi. "211 Virological Charactrization of HIV-1 Acute Infection by Ultra-Sensitive Next Generation Sequencing." JAIDS Journal of Acquired Immune Deficiency Syndromes 56 (April 2011): 90. http://dx.doi.org/10.1097/01.qai.0000397393.67006.42.

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Tang, Shixing, Jiangqin Zhao, James J. Storhoff, Philip J. Norris, Richard F. Little, Robert Yarchoan, Susan L. Stramer, et al. "Nanoparticle-Based Biobarcode Amplification Assay (BCA) for Sensitive and Early Detection of Human Immunodeficiency Type 1 Capsid (p24) Antigen." JAIDS Journal of Acquired Immune Deficiency Syndromes 46, no. 2 (October 2007): 231–37. http://dx.doi.org/10.1097/qai.0b013e31814a554b.

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Ellis, Giovanina M., Libby C. Page, Blaire E. Burman, Susan Buskin, and Lisa M. Frenkel. "Increased Detection of HIV-1 Drug Resistance at Time of Diagnosis by Testing Viral DNA With a Sensitive Assay." JAIDS Journal of Acquired Immune Deficiency Syndromes 51, no. 3 (July 2009): 283–89. http://dx.doi.org/10.1097/qai.0b013e3181a9972c.

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Boger, Michael S., Ayumi Shintani, Leigh Anne Redhage, Valerie Mitchell, David W. Haas, Jason D. Morrow, and Todd Hulgan. "Highly Sensitive C-Reactive Protein, Body Mass Index, and Serum Lipids in HIV-Infected Persons Receiving Antiretroviral Therapy: A Longitudinal Study." JAIDS Journal of Acquired Immune Deficiency Syndromes 52, no. 4 (December 2009): 480–87. http://dx.doi.org/10.1097/qai.0b013e3181b939e5.

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&NA;. "Highly Sensitive C-Reactive Protein, Body Mass Index, and Serum Lipids in HIV-Infected Persons Receiving Antiretroviral Therapy: A Longitudinal Study: Erratum." JAIDS Journal of Acquired Immune Deficiency Syndromes 53, no. 1 (January 2010): 157. http://dx.doi.org/10.1097/qai.0b013e3181cc804e.

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Wang, Hongxiang, Gen Li, and Yuefeng Ji. "Phase and amplitude regeneration of a rectangular 8-QAM in a phase-sensitive amplifier with low-order harmonics." Applied Optics 56, no. 3 (January 13, 2017): 506. http://dx.doi.org/10.1364/ao.56.000506.

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Sánchez, Victoria, Mar Masiá, Catalina Robledano, Sergio Padilla, Blanca Lumbreras, Eva Poveda, Carmen De Mendoza, Vicente Soriano, and Félix Gutiérrez. "A Highly Sensitive and Specific Model for Predicting HIV-1 Tropism in Treatment-Experienced Patients Combining Interpretation of V3 Loop Sequences and Clinical Parameters." JAIDS Journal of Acquired Immune Deficiency Syndromes 56, no. 1 (January 2011): 51–58. http://dx.doi.org/10.1097/qai.0b013e3181fc012b.

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Wong, Ilene Y., Nicholas V. Lawrence, Helen Struthers, James McIntyre, and Gerald H. Friedland. "Development and Assessment of an Innovative Culturally Sensitive Educational Videotape to Improve Adherence to Highly Active Antiretroviral Therapy in Soweto, South Africa." JAIDS Journal of Acquired Immune Deficiency Syndromes 43, Supplement 1 (December 2006): S142—S148. http://dx.doi.org/10.1097/01.qai.0000248345.02760.03.

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James Popham, W., David C. Berliner, Neal M. Kingston, Susan H. Fuhrman, Steven M. Ladd, Jeffrey Charbonneau, and Madhabi Chatterji. "Can today’s standardized achievement tests yield instructionally useful data?" Quality Assurance in Education 22, no. 4 (August 26, 2014): 303–18. http://dx.doi.org/10.1108/qae-07-2014-0033.

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Purpose – Against a backdrop of high-stakes assessment policies in the USA, this paper explores the challenges, promises and the “state of the art” with regard to designing standardized achievement tests and educational assessment systems that are instructionally useful. Authors deliberate on the consequences of using inappropriately designed tests, and in particular tests that are insensitive to instruction, for teacher and/or school evaluation purposes. Methodology/approach – The method used is a “moderated policy discussion”. The six invited commentaries represent voices of leading education scholars and measurement experts, juxtaposed against views of a prominent leader and nationally recognized teacher from two American education systems. The discussion is moderated with introductory and concluding remarks from the guest editor, and is excerpted from a recent blog published by Education Week. References and author biographies are presented at the end of the article. Findings – In the education assessment profession, there is a promising movement toward more research and development on standardized assessment systems that are instructionally sensitive and useful for classroom teaching. However, the distinctions among different types of tests vis-à-vis their purposes are often unclear to policymakers, educators and other test users, leading to test misuses. The authors underscore issues related to validity, ethics and consequences when inappropriately designed tests are used in high-stakes policy contexts, offering recommendations for the design of instructionally sensitive tests and more comprehensive assessment systems that can serve a broader set of educational evaluation needs. As instructionally informative tests are developed and formalized, their psychometric quality and utility in school and teacher evaluation models must also be evaluated. Originality/value – Featuring perspectives of scholars, measurement experts and educators “on the ground”, this article presents an open and balanced exchange of technical, applied and policy issues surrounding “instructionally sensitive” test design and use, along with other types of assessments needed to create comprehensive educational evaluation systems.

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Tefferi, A., BA Owen, WL Nichols, TE Witzig, and WG Owen. "Isolation of a heparin-like anticoagulant from the plasma of a patient with metastatic bladder carcinoma." Blood 74, no. 1 (July 1, 1989): 252–54. http://dx.doi.org/10.1182/blood.v74.1.252.252.

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Abstract A 73-year-old woman with metastatic transitional cell carcinoma of the bladder developed vaginal bleeding a few days after undergoing radical cystectomy. She had no other signs of mucocutaneous bleeding. Coagulation studies revealed a markedly prolonged thrombin time (greater than 600 seconds), a slightly prolonged reptilase time (20 seconds), and mildly elevated fibrinogen (4.39 g/L), and fibrin D-dimer (200 to 500 ng/mL) levels. Treatment of the patient's plasma in vitro with protamine or barium sulfate normalized the thrombin time. The anticoagulant activity corresponded to 0.15 heparin U/mL when measured by a thrombin time assay using normal plasma as substrate and standardized with porcine heparin. The anticoagulant was quantitatively bound to and subsequently eluted with 1 mol/L NaCl from quaternary aminoethyl (QAE) Sephadex, and then isolated by affinity chromatography on immobilized antithrombin III. The isolated anticoagulant was shown to be sensitive to heparinase digestion. Therefore, the inhibitor has functional and chemical properties similar to those of high-affinity heparin. Thus far, this is the only anticoagulant of this type isolated from the plasma of a patient bearing a tumor other than plasma cell myeloma.

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Tefferi, A., BA Owen, WL Nichols, TE Witzig, and WG Owen. "Isolation of a heparin-like anticoagulant from the plasma of a patient with metastatic bladder carcinoma." Blood 74, no. 1 (July 1, 1989): 252–54. http://dx.doi.org/10.1182/blood.v74.1.252.bloodjournal741252.

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A 73-year-old woman with metastatic transitional cell carcinoma of the bladder developed vaginal bleeding a few days after undergoing radical cystectomy. She had no other signs of mucocutaneous bleeding. Coagulation studies revealed a markedly prolonged thrombin time (greater than 600 seconds), a slightly prolonged reptilase time (20 seconds), and mildly elevated fibrinogen (4.39 g/L), and fibrin D-dimer (200 to 500 ng/mL) levels. Treatment of the patient's plasma in vitro with protamine or barium sulfate normalized the thrombin time. The anticoagulant activity corresponded to 0.15 heparin U/mL when measured by a thrombin time assay using normal plasma as substrate and standardized with porcine heparin. The anticoagulant was quantitatively bound to and subsequently eluted with 1 mol/L NaCl from quaternary aminoethyl (QAE) Sephadex, and then isolated by affinity chromatography on immobilized antithrombin III. The isolated anticoagulant was shown to be sensitive to heparinase digestion. Therefore, the inhibitor has functional and chemical properties similar to those of high-affinity heparin. Thus far, this is the only anticoagulant of this type isolated from the plasma of a patient bearing a tumor other than plasma cell myeloma.

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Cui, Jiabin, Guo-Wei Lu, Hongxiang Wang, and Yuefeng Ji. "On-Chip Optical Vector Quadrature De-Multiplexer Proposal for QAM De-Aggregation by Single Bi-Directional SOA-Based Phase-Sensitive Amplifier." IEEE Access 7 (2019): 763–72. http://dx.doi.org/10.1109/access.2018.2885815.

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Rajesh Kumar Chawla, Koteswara Rao G S N, Umasankar Kulandaivelu, Siva Prasad Panda, and Rajasekhar Reddy Alavala. "Development and Validation of a Headspace Gas Chromatographic (HS-GC) Method for Determination of Residual Solvents in Nitazoxanide API." International Journal of Research in Pharmaceutical Sciences 11, SPL4 (December 21, 2020): 1719–27. http://dx.doi.org/10.26452/ijrps.v11ispl4.4362.

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Controlling residual solvents in the drug substances or active pharmaceutical ingredients (API) is mandatory to the specified limits as per the International Conference on Harmonisation (ICH) Q3C guidelines. Residual solvents in pharmaceuticals are mostly determined by Gas Chromatography with Headspace. A simple and sensitive headspace gas chromatographic (HS-GC) method has been developed for the determination of Acetone, Dichloromethane and Cyclohexane in Nitazoxanide API. The separation of analytes was achieved with DB – 624 (30 m length, 0.53 mm inner diameter and 3.0 μm in film thickness) capillary column. Dimethyl formamide was used as a diluent. Nitrogen was used as carrier gas with 3.0 mL/minutes and Flame ionisation detector (FID) for detecting analytes. The oven temperature was set at 60°C for 5 minutes at initial and programmed at a rate of 20°C per minute to a final temperature of 240°C for 2 minutes. Run time was 16 minutes, and total GC cycle time was 25 minutes. The spilt ratio used as 1:20 to get optimum peak response. The developed method was validated as per the ICH guidelines for specificity, accuracy, precision, linearity, range, the limit of detection, the limit of quantification and robustness. The results of validation were indicated no interference, good recoveries, precise, linear, rugged and robust method, suitable for the determination of residual solvents in Nitazoxanide API for research and routine quality control laboratory.

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Lua, Lu, Pei Tong, Xiaowen Yub, Chungen Panc, Peng Zou, Ying-hua Chen, and Shibo Jiang. "ST103 HIV-1 variants with mutations in the gp41 pocket region are resistant to HIV fusion inhibitors with pocket-binding domain, but sensitive to T20." JAIDS Journal of Acquired Immune Deficiency Syndromes 62 (April 2013): S65. http://dx.doi.org/10.1097/01.qai.0000429264.98091.c5.

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Omekudo, Oviemuno, Emmanuel Ikpefan, and Felix Enwa. "Antimicrobial and antioxidant studies of the methanolic extract of Cnestis ferruginea DC (connaraceae) leaves." Journal of Current Biomedical Research 2, no. 6, November-December (December 31, 2022): 683–96. http://dx.doi.org/10.54117/jcbr.v2i6.9.

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Extract from Cnestis ferruginea leaves has been used worldwide due to its antimicrobial and antioxidant activities in treating related ailments. The aim of this study is to investigate the antimicrobial and antioxidant studies of the extract of Cnestis ferruginea DC (Connaraceae) leaves. The methanol extract was evaluated for the presence of phytochemicals. The methanol extract was evaluated for antimicrobial activities against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Candida albicans, and Aspergillus spp. Thereafter, antioxidant activities were also carried out with DPPH (2,2- Diphenyl-1-picryl hydrazyl) and FRAP (Ferric reducing antioxidant power) methods using ascorbic acid as standard for DPPH and FRAP. The total phenol and total flavonoid contents were determined using garlic acid and quercetin respectively. The results indicate the presence of phytochemicals such as, tannins, alkaloids, terpenoids, saponins, cardiac glycosides, anthraquinones, and flavonoids. The results also indicate that all the organisms were sensitive to the various extract concentrations used (100 – 6.25 mg/mL). The minimum inhibitory concentration demonstrated by the organisms include, E. coli (12.5mg/mL), B. subtilis (6.25mg/mL), S. aureus (12.5mg/mL), P. aeruginosa (6.25mg/mL), C. Albicans (100mg/mL), and A. spp (100mg/mL). The mean % inhibition for DPPH increases with increasing concentrations compared to that of FRAP that decreases with increasing concentrations. The total phenol and flavonoid contents of the crude extract of C. ferruginea leaves are 82.89 + 0.06 mg/GAE/g and 57.09 + 0.04 mg/QAE/g respectively. This study showed that the plant extract exhibited good antimicrobial and antioxidant activity against the test microorganisms.

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Abood Yasir OKAB, Alaa, and Manal B SALIH. "ANTIBIOTIC SUSCEPTIBILITY OF ESCHERICHIA COLI ISOLATE FROM URINARY TRACT INFECTION OF THALASSEMIC PATIENTS IN THI-QAR PROVINCE." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 28, no. 28 (June 20, 2020): 22–33. http://dx.doi.org/10.48141/sbjchem.v28.n28.2020.04_okab_pgs_22_33.pdf.

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Escherichia coli (E. coli) is the most common type of pathogen that causes Urinary tract infection disease. It can be presented as a pathogenic or non-pathogenic strain and found not only in the animal but also in the human intestine. This bacterium can cause opportunistic infection when the human host comprised of thalassemia patients or changes the healthy hemostatic flora. This study aimed to analyze the presence of bacteria in thalassemia patients with urinary tract infection. A total of 303 samples were collected during the period from August 2019 to January 2020 from thalassemia patients who suffered from urinary tract infection. The results showed that there were 6.9% of patients infected with E. coli, 2.6% of patients were infected with S. aureus, 0.7% with both Proteus and Klebsiella, while 89.1% of patients had a negative sample for bacteria. Also, the incidence of urinary tract infections in females is higher than in males. Besides, its occurrence in rural areas is higher than in city residents. Moreover, among 16 antibiotics tested to sensitize bacteria to antibiotics, Imipenem showed 100% efficacy on all isolated bacteria. In contrast, Netilmicin showed 80.1% efficacy, Gentamycin 80.1%, and Amikacin 76.2%. Ampicillin, Aztreonam, Amoxicillin-Clavulanic Acid, Tetracycline, and Ticarcillin-Clavulanic Acid, did not show any effectiveness toward the bacteria while other antibiotics showed different activities. Furthermore, the isolated microbes from thalassemia patients were the highest resistance to antibiotics in comparison with other studies, and this antibiotic-resistant may be due to the weakening of the patient's immune status and frequent blood taking and the antibodies it contains.

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Okab, Alaa Abood Yasir, and Manal Salih. "Antibiotic Susceptibility of Escherichia Coli Isolate from Urinary Tract Infection Of Thalassemic Patients in Thi-Qar Province." Southern Brazilian Journal of Chemistry 28, no. 28 (June 20, 2020): 22–33. http://dx.doi.org/10.37633/sbjc.28(28)2020.22-33.

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Escherichia coli (E. coli) is the most common type of pathogen that causes Urinary tract infection disease. It can be presented as pathogenic or non-pathogenic strain and found not only in the animal but also in the human intestine. This bacterium can cause opportunistic infection when the human host comprised of thalassemia patients or changes the healthy hemostatic flora. This study aimed to analyze the presence of bacteria in thalassemia patients with urinary tract infection. A total of 303 samples were collected during the period from August 2019 to January 2020 from thalassemia patients who suffered from urinary tract infection. The results showed that there were 6.9% of patients infected with E. coli, 2.6% of patients were infected with S. aureus, 0.7% with both Proteus and Klebsiella, while 89.1% of patients had a negative sample for bacteria. Also, the incidence of urinary tract infections in females is higher than in males. Besides, its occurrence in rural areas is higher than in city residents. Moreover, among 16 antibiotics tested to sensitize bacteria to antibiotics, Imipenem showed 100% efficacy on all isolated bacteria. In contrast, Netilmicin showed 80.1% efficacy, Gentamycin 80.1%, and Amikacin 76.2%. Ampicillin, Aztreonam, Amoxicillin-Clavulanic Acid, Tetracycline, and Ticarcillin-Clavulanic Acid, did not show any effectiveness toward the bacteria while other antibiotics showed different activities. Furthermore, the isolated microbes from thalassemia patients were the highest resistance to antibiotics in comparison with other studies, and this antibiotic-resistant may be due to the weakening of the patient's immune status and frequent blood taking and the antibodies it contains.

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PIACENZA, L., R. RADI, F. GOÑI, and C. CARMONA. "CuZn superoxide dismutase activities from Fasciola hepatica." Parasitology 117, no. 6 (December 1998): 555–62. http://dx.doi.org/10.1017/s0031182098003394.

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The levels of superoxide dismutase (SOD) were determined in detergent-soluble, somatic and excretion–secretion (E–S) preparations from adult Fasciola hepatica using the xanthine oxidase system and visualized in substrate gels. Compared to detergent-soluble and somatic extracts, E–S products showed the highest SOD activity (88 ·5 U/mg), indicating active release to the medium in which parasites were maintained. SOD specific activity was also detected at high levels in E–S products from 3-week-old and 5-week-old immature migrating flukes (25 and 143 U/mg, respectively). In all preparations except for the somatic extract, the activity was characterized as cyanide-sensitive CuZn SOD. Differences in SOD isoenzyme profiles between the extracts were observed in native polyacrylamide gel electrophoresis: the somatic and detergent-soluble extracts exhibited 1 band of activity while the E–S products from immature and adults flukes contained 2 and 3 migrating bands, respectively. SOD was purified from the detergent-soluble extract and E–S products of adult worms by a combination of ultrafiltration, gel filtration on Sephacryl S-200 HR and ion-exchange chromatography on QAE Sephadex A-50. The SOD from detergent-soluble extract showed, by SDS–PAGE analysis, 1 band of 16 kDa apparent molecular weight. The SOD from E–S products showed 2 bands of 16 and 60 kDa apparent molecular weight. N-terminal sequence analysis of the 16 kDa band from the detergent-soluble preparation showed some similarity with Schistosoma mansoni cytoplasmic SOD. These enzymes may have a potential role in the evasion of the oxidative burst killing mechanism by immune cells.

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Pismenetskaya, I. U., and T. D. Butters. "Molecular and cellular mechanisms of profile changes of charged blood plasma free oligosaccharides in myeloproliferative disorders." Visnyk of Dnipropetrovsk University. Biology, medicine 7, no. 1 (March 12, 2016): 59–64. http://dx.doi.org/10.15421/021611.

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Free oligosaccharides (FOS) are unbound to proteins or lipids structural analogs of their glycans. FOS appear as by-products of endoplasmic reticulum synthesis, cell control folding with endoplastic reticulum-associated degradation and lysosomal/endosomal breakdown of glycoconjugates. They may be either neutral or negatively charged depending on the way of their formation. Charged FOS appear during degradation of glycoconjugates in the lysosomal/endosomal system and are natural substrates for lysosomal sialidase-1. FOS are formed inside the cell but some of them can get into the extracellular space, and then into the blood and urine, where both neutral and charged structures were found. Secretion of charged FOS outside of the cell is most likely to be caused by the lysosomal exocytosis. The activity of neuraminidase-1 is known to be connected with the intensity of the lysosomal exocytosis. In our previous studies, it was found that HPLC-profiles of charged FOS were specifically changed in acute and chronic myeloproliferative blood disorders. The objective of this work was to analyze the molecular and cellular mechanisms of these changes and to test the hypothesis of their association with the activity change of lysosomal neuraminidase-1. Plasma samples of patients with acute and chronic leukaemia – polycytaemia vera, chronic idiopathic myelofibrosis, hypoplastic anaemia, myelodysplastic syndrome with transformation, acute lymphatic and acute myelomonocytic leukaemia – were collected for investigation. Plasma samples of practically healthy volunteers were obtained and used for comparison. After plasma deproteinization and FOS purification the oligosaccharides were labelled with anthranilic acid (2-AA), separated into the neutral and charged fractions with QAE Sephadex (Q25-120) chromatography and analysed using high-performance liquid chromatography (HPLC). Glucose unit values were determined following comparison with a 2-AA-labelled glucose oligomer ladder derived from a partial hydrolysate of dextran as an external standard. The data were collected and processed using Empower software. The charged FOS were digested with the sialidase from Arthrobacter ureafaciens. 2-AA – labelled free oligosaccharides from transferrin were used as an external standard for the structure decoding. In this paper, the changes in neraminidase-1 activity was first demonstrated on natural substrates, free oligosaccharides, in vivo. Chromatographic profiles of charged plasma FOS of patients with acute and chronic hematological malignancies revealed decreasing of neuraminidase-1 activity and increasing of the lysosomal exocytosis. Thus, chromatographic profiles of charged plasma FOS appeared to be a sensitive parameter of the lysosomal/endosomal status in normal or pathological states and to open up new prospects for their applications to the development of anti-cancer drugs designed to block the work of the lysosomal/endosomal system and monitoring of their action.

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Gregorchuk, Branden S. J., Shelby L. Reimer, Daniel R. Beniac, Shannon L. Hiebert, Timothy F. Booth, Michelle Wuzinski, Brielle E. Funk, et al. "Antiseptic quaternary ammonium compound tolerance by gram-negative bacteria can be rapidly detected using an impermeant fluorescent dye-based assay." Scientific Reports 10, no. 1 (November 25, 2020). http://dx.doi.org/10.1038/s41598-020-77446-8.

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AbstractBiocides such as quaternary ammonium compounds (QACs) are potentially important contributors towards bacterial antimicrobial resistance development, however, their contributions are unclear due to a lack of internationally recognized biocide testing standards. Methods to detect QAC tolerance are limited to laborious traditional antimicrobial susceptibility testing (AST) methods. Here, we developed a rapid fluorescent dye-based membrane impermeant assay (RFDMIA) to discriminate QAC susceptibility among Gram-negative Enterobacterales and Pseudomonadales species. RFDMIA uses a membrane impermeant fluorescent dye, propidium iodide, in a 30-min 96-well fluorescent microplate-based assay where cell suspensions are exposed to increasing QAC concentrations. Our results demonstrate that RFDMIA can discriminate between QAC-susceptible and QAC-adapted Escherichia coli tolerant phenotypes and predict benzalkonium and cetrimide tolerance in all species tested except for intrinsically fluorescent Pseudomonas aeruginosa. RFDMIA identified a close association to minimum inhibitory concentration values determined by broth microdilution AST and increasing fluorescent dye emission values. RFDMIA emission values and scanning electron microscopy results also suggest that CET-adapted E. coli isolates have a CET dependence, where cells require sub-inhibitory CET concentrations to maintain bacilliform cell integrity. Overall, this study generates a new, rapid, sensitive fluorescent assay capable of detecting QAC-susceptible Gram-negative bacteria phenotypes and cell membrane perturbations.

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Carneiro, L., D. Rodrigues, and D. Paiva. "Knowledge on heart disease of the person with ischemic heart disease." European Journal of Cardiovascular Nursing 22, Supplement_1 (July 28, 2023). http://dx.doi.org/10.1093/eurjcn/zvad064.133.

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Abstract Funding Acknowledgements Type of funding sources: None. Introduction Instruments that allow us to measure the users' knowledge about their health can be useful in clinical practice to allow adjusting interventions, quantifying health gains and developing cost-effective interventions. Purpose To determine knowledge about heart disease among the population with diagnosed ischemic heart disease. Methods Cross-sectional, descriptive study using a sequential sample of patients with ischemic heart disease admitted between May 2nd and July 30th, 2022 at the cardiology service of the Hospital Centre of our city. A self-administered questionnaire was developed and applied to 165 patients, encompassing several dimensions: sociodemographic characteristics, clinical history, lifestyle, number of hospitalizations due to heart disease and characterization of the current admission. An instrument was used to determine knowledge about heart disease (Questionário de Avaliação de Conhecimentos em Doença Cardíaca: QACDC - Questionnaire for the Assessment of Knowledge in Heart Disease), the Medical Term Recognition Test (METER) to assess literacy and the Hospital Anxiety and Depression Scale (HADS). Patients were assessed during their stay at the hospital unit where they had been admitted due to an acute illness or for elective procedures. Using, preferably, parametric tests, we studied the association between the average score obtained in the QAC-DC and the variables studied. Results Women, the less educated and those with inadequate literacy levels were the groups with the lowest levels of knowledge. Regarding the areas of knowledge, the least recognized cardiovascular risk factors were the family history of ischemic heart disease (recognized by 86%), diabetes mellitus (recognized by 73%) and gender (marked by 19% of respondents). The most frequently identified symptom of heart disease was chest discomfort (92%), followed by difficulty breathing or shortness of breath (84%), while jaw, neck or interscapular discomfort was only recognized by 54% of respondents. Symptoms of stroke and acute myocardial infarction were confused by 88% of the sample. Conclusions There are important gaps in some areas of knowledge about heart disease among patients with ischemic heart disease. These gaps are particularly important in certain patient subgroups. Health intervention strategies must be sensitive to these data. The QAC-DC knowledge assessment instrument proved to be reliable, valid and applicable in clinical practice.

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Habibi, Alireza, Ahmad Zainul Musthofa, Elaheh Adibi, Johan Ekström, Thomas Schmidt, and Eddwi Hesky Hasdeo. "Kerr and Faraday rotations in topological flat and dispersive band structures." New Journal of Physics, May 17, 2022. http://dx.doi.org/10.1088/1367-2630/ac706d.

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Abstract Integer quantum Hall (IQH) states and quantum anomalous Hall (QAH) states show the same static (dc) response but distinct dynamical (ac) response. In particular, the ac anomalous Hall conductivity profile σyx(ω) is sensitive to the band shape of QAH states. For example, dispersive QAH bands shows resonance profile without a sign change at the band gap while the IQH states shows the sign change resonance at the cyclotron energy. We argue by flattening the dispersive QAH bands, σyx(ω) should recover to that of flat Landau bands in IQH, thus it is necessary to know the origin of the sign change. Taking a topological lattice model with tunable bandwidth, we found that the origin of the sign change is not the band gap but the Van Hove singularity energy of the QAH bands. In the limit of small bandwidth, the flat QAH bands recovers σyx(ω) of the IQH Landau bands. Because of the Hall response, these topological bands exhibit giant polarization rotation and ellipticity in the reflected waves (Kerr effect) and rotation in the order of fine structure constant in the transmitted waves (Faraday effect) with profile resembles σyx(ω). Our results serve as a simple guide to optical characterization for topological flat bands.

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Heyde, Benjamin Justus, Stefanie P. Glaeser, Linda Bisping, Kristin Kirchberg, Rüdiger Ellinghaus, Jan Siemens, and Ines Mulder. "Smectite clay minerals reduce the acute toxicity of quaternary alkylammonium compounds towards potentially pathogenic bacterial taxa present in manure and soil." Scientific Reports 10, no. 1 (September 21, 2020). http://dx.doi.org/10.1038/s41598-020-71720-5.

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Abstract Quaternary alkylammonium compounds (QAACs) are a group of cationic surfactants which are disinfectants with numerous industrial and agricultural applications and frequently released into the environment. One recent hypothesis is that bacteria present in soil will be protected from acute toxic effects of QAACs in the presence of expandable layer silicates due to interlayer sorption. We therefore studied bacterial growth kinetics with high temporal resolution and determined minimal inhibitory concentrations (MICs) of two QAACs, benzyldimethyldodecylammonium chloride (BAC-C12) and didecyldimethylammonium chlorid (DADMAC-C10), for eight strains of different bacterial taxa (Escherichia coli, Acinetobacter, Enterococcus faecium, Enterococcus faecalis, and Pseudomonas fluorescens) in relation to QAAC sorption to smectite and kaolinite. The MICs of BAC-C12 and DADMAC-C10 were in the absence of smectite and kaolinite in the order of 10 to 30 µg mL−1 and 1.0 to 3.5 µg mL−1 for all strains except the more sensitive Acinetobacter strain. For all tested strains and both tested QAACs, the presence of smectite increased apparent MIC values while kaolinite had no effect on MICs. Sorption curves without bacteria showed that smectite sorbed larger amounts of QAACs than kaolinite. Correcting nominal QAAC concentrations employed in toxicity tests for QAAC sorption using the sorption curves explained well the observed shifts in apparent MICs. Transmission electron microscopy (TEM) demonstrated that the interlayer space of smectite expanded from 13.7 ± 1 Å to 19.9 ± 1.5 Å after addition of BAC-C12. This study provides first evidence that low charge 2:1 expandable layer silicates can play an important role for buffering QAAC toxicity in soils.

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Manzano, Alberto, Daniele Musso, and Álvaro Leitao. "Real quantum amplitude estimation." EPJ Quantum Technology 10, no. 1 (February 3, 2023). http://dx.doi.org/10.1140/epjqt/s40507-023-00159-0.

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AbstractWe introduce the Real Quantum Amplitude Estimation (RQAE) algorithm, an extension of Quantum Amplitude Estimation (QAE) which is sensitive to the sign of the amplitude. RQAE is an iterative algorithm which offers explicit control over the amplification policy through an adjustable parameter. We provide a rigorous analysis of the RQAE performance and prove that it achieves a quadratic speedup, modulo logarithmic corrections, with respect to unamplified sampling. Besides, we corroborate the theoretical analysis with a set of numerical experiments.

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Shimizu, S., T. Kobayashi, T. Kazama, T. Umeki, K. Enbutsu, R. Kasahara, and Y. Miyamoto. "Optical phase‐sensitive amplification of higher‐order QAM signal with single Mach–Zehnder amplitude modulator." Electronics Letters, December 31, 2020. http://dx.doi.org/10.1049/ell2.12002.

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"Antimicrobial Resistance Pattern and Plasmid Profile of Salmonella enterica Isolated from Diarrheal Children in Thi-Qar Province/Iraq." University of Thi-Qar Journal of Science, December 5, 2020, 49–53. http://dx.doi.org/10.32792/utq/utjsci/vol7/2/12.

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The aims of this work were to investigate the antimicrobial pattern and plasmid profile of different antibiotic resistant Salmonella species isolated from diarrheal children in Thi-Qar province and to find a possible relationship between resistance patterns and plasmid profile. Salmonella isolates were tested against 15 commonly used antimicrobial agents using the disc diffusion method to determine the resistance Patterns while plasmid DNA was extracted using alkaline lysis method and separated by agarose gel electrophoresis. all isolates were sensitive to the Amikacin and Gentamycin whereas all isolates were resistances to erythromycin; the most prevalent pattern included resistance to Nalidixic acid (50%) , Cefixim and Cefotaxim (37.5%), and to trimethoprim-sulphamethoxazole, Amoxicillin- clavulanic acid and Ampicillin (33.3%).Furthermore, many isolates were resistant to Tetracycline and Chloramphenicol (29.1%), Ciprofloxacin and Nitrofurantion (25%) and Azithromycin (20.8%), while only 12% of isolates were resistances to Norfloxacin. Plasmid analysis of clinical isolates showed several large and small plasmids were extracted from (91.7%) of the isolates and some isolates carried one or more plasmids.

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Hammady, Ahmed Alaj, and Alaa Hussein Oleiwi Al-Awadi. "Evaluation efficiency and phenotypic analysis to ITS-2gene targeting sample from patient infested with scabies. (S. scabiei Var.hominis).in Thi-Qar province/Iraq." International journal of health sciences, August 29, 2022, 8754–64. http://dx.doi.org/10.53730/ijhs.v6ns6.12274.

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The second internal transcribed spacer region of the nuclear ribosomal gene cluster (ITS2). This cluster consists of three genes (18S rDNA, 5.8S rDNA and 28S rDNA) which have transcribed into RNA. Nevertheless, not translated into protein. It is sensitive to detect S. scabiei DNA even after treatment. In addition, this gene can detect genetic variations of species that are related taxonomically. This study aimed to determine and compare the sensitivity and specificity of ITS-2, S. scabiei, genes to the microscopic examination of scabies skin scrapings. In addition, employs, The ITS2 as a powerful tool for studies of intraspecific variation and phylogenies of closely related species. The results of the PCR for the diagnosis of S. scabiei .var .hominis was,(50%) of total sample Frome .25,(50%) mite-positive and 25(50%) mite-negative ,50%,Sensitivity 50% specificity, Positive predictive value (60%),negative predictive value (40%), The sensitivity of the scabies PCR reached between (30% and 60%) globally, ITS-2 region is suitable for phylogenetic studies of astigmatic mites. as this region shows comparatively higher variation between the diverse species of mites and lower distinction within the species. These astigmatic mites are located in the phylogenetic tree based on their genetic features>

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Journal articles on the topic 'SENSITIVE QAC'

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