John Bauer: Painter of a Star-Spangled Fairy-Tale World

NASA Astrophysics Data System (ADS)

Sundin, M.; Roslund, C.

Several generations of Swedish children have become acquainted with the world of fairy-tales through illustrations by the painter John Bauer in the Christmas magazine Goblins and Trolls. Next to his portrayal of grotesque but humorous trolls, his paintings of the Moon and the starry sky are among those best remembered. These pictures have inspired very many Swedes to take pleasure in the beauty of the stars and the movement of the Moon.

Role of Superoxide Dismutase in the Photochemical Response of Cultured RPE Cells to Laser Exposure at 413 nm

DTIC Science & Technology

2007-11-01

TX 78228 Optical Radiation Branch 2624 Louis Bauer Dr. Brooks City-Base, TX 78235-5128 8. PERFORMING ORGANIZATION REPORT NUMBER AFRL 711...Effectiveness Directorate Directed Energy Bioeffects Division Optical Radiation Branch 2624 Louis Bauer Dr. Brooks City-Base, TX 78235-5128 711 HPW...K, Coherent) was used for its 413-nm line. Verification of laser wavelength was performed with a spectrometer (Ocean Optics ). Figure 1 provides a

Evaluation of BAUER High Pressure Breathing Air P-2 Purification System

DTIC Science & Technology

1991-08-01

and is a coalescing type separator that removes oil and water vapors suspended in the compressed air . The molecular sieve is made to adsorb oil and...filtering, moisture separation, and prevents compressed air return from the charged air storage flasks to the compressor during unit shutdown. A manual...1111111111111 1111 IE IH fil91i C NAVY EXPERIMENTAL DIVING UNIT REPORT NO. 10-91 EVALUATION OF BAUER HIGH PRESSURE BREATHING AIR P-2 PURIFICATION SYSTEM GEORGE D

Mirror Measurement Device

NASA Technical Reports Server (NTRS)

1992-01-01

A Small Business Innovation Research (SBIR) contract led to a commercially available instrument used to measure the shape profile of mirror surfaces in scientific instruments. Bauer Associates, Inc.'s Bauer Model 200 Profilometer is based upon a different measurement concept. The local curvature of the mirror's surface is measured at many points, and the collection of data is computer processed to yield the desired shape profile. (Earlier profilometers are based on the principle of interferometry.) The system is accurate and immune to problems like vibration and turbulence. Two profilometers are currently marketed, and a third will soon be commercialized.

Damage Thresholds for Cultures RPE Cells Exposed to Lasers at 532 nm and 458 nm

DTIC Science & Technology

2007-06-01

ADDRESS(ES) Air Force Research Laboratory H uman Effectiveness Directorate Directed Energy Bioeffects Division Optical Radiation Branch 2624 Louis Bauer Dr...Directed Energy Bioeffects Division Optical Radiation Branch 2624 Louis Bauer Dr. Brooks City-Base, TX 7 8235-5128 1 0. SPoNSOR/MON|TOR’S ACRONYM(S) AFRL...p t b m T a i b i fi d D o a T t i f e t A B r Journal of Biomedical Optics 123, 034030 May/June 2007 J amage thresholds for cultured retinal

Operations Tempo and Turnover Intentions: An Exploratory Study of the Air Force’s Explosive Ordnance Disposal (EOD) Career Field and Development of the Air Force Civil Engineer Retention Questionnaire

DTIC Science & Technology

2009-03-01

turnover (e.g., Barrick & Zimmerman, 2005; Maertz & Campion, 2004; Bauer, Erdogan , Liden, & Wayne, 2006), (b) a continued focus on stress- and change...M. A. (1998). Dimensions of psychological stress in peacekeeping operations. Military Medicine , 587-593. 69 Bauer, T. N., Erdogan , B., Liden...good job are seldom blocked by red tape .        8. I like doing the things I do at work.        9. I feel unappreciated by the Air Force

Dynamic thermal expansivity of liquids near the glass transition.

PubMed

Niss, Kristine; Gundermann, Ditte; Christensen, Tage; Dyre, Jeppe C

2012-04-01

Based on previous works on polymers by Bauer et al. [Phys. Rev. E 61, 1755 (2000)], this paper describes a capacitative method for measuring the dynamical expansion coefficient of a viscous liquid. Data are presented for the glass-forming liquid tetramethyl tetraphenyl trisiloxane (DC704) in the ultraviscous regime. Compared to the method of Bauer et al., the dynamical range has been extended by making time-domain experiments and by making very small and fast temperature steps. The modeling of the experiment presented in this paper includes the situation in which the capacitor is not full because the liquid contracts when cooling from room temperature down to around the glass-transition temperature, which is relevant when measuring on a molecular liquid rather than a polymer.

In Vitro Assay of Ethanolic Heat Reflux Extract of Nicotiana tabacum L. var Virginia Against Nosocomial Bacteria Pathogen

NASA Astrophysics Data System (ADS)

Pramono, Andri; Fauzantoro, Ahmad; Rizki Hidayati, Irma; Hygea, Arina; Puspita, Oktaviani Sandra; Muktamiroh, Hikmah; Simanjuntak, Kristina; Gozan, Misri

2018-03-01

Tobacco plays an important role in international trade as one of the export commodities. Indonesia is one of the good quality export contributors of tobacco leaves in the world. Nevertheless, tobacco is used only as a raw material for the cigarette industries, and the rise on anti-cigarette regulations prompted the exploration of alternative product from tobacco plants. The content of alkaloids, flavonoids, terpenoids and steroids in tobacco leaves were reported in literatures as antibacterial. Therefore, this study proposed in vitro assay of the ethanolic heat reflux extract (EHRE) of Nicotiana tabacum var. Virginia against nosocomial bacteria pathogen ((Pseudomonas aeruginosa (ATCC 27853), Eschericia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212)). Kirby-bauer diffusion method was used for this assay. The concentration of the EHRE for Kirby-bauer assay were 20; 40; 60; 80; and 100%. The presence of clear zones on Kirby-bauer test, against the growth of each nosocomial bacteria pathogen show that tobacco extract has antibacterial effect. Statistical analysis result showed that each extract concentration had significant difference value (p <0,05). This study indicated that the content (alkaloids, flavonoids, terpenoids and steroids) of tobacco leaf extracts (N. tabacum) has potential as antibacterial against nosocomial bacteria pathogen. Nevertheless, optimization of tobacco leaf extract to obtain maximum active ingredient still needs to be done. This study is important for further development of the tobacco leaf extract as antibacterial

77 FR 58354 - Foreign-Trade Zone 265-Conroe, TX; Notification of Proposed Production Activity, Bauer...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-20

..., packing crates, decals, textile straps, mirrors, insulation, articles of steel (shapes, angles, bars, rods...-conditioner components, heat exchangers, filters, fire extinguishers, hydraulic jacks/hoists, parts of boring...

Genetics Home Reference: deafness-dystonia-optic neuronopathy syndrome

MedlinePlus

... usually develop a gradual decline in thinking and reasoning abilities (dementia) in their forties. The lifespan of ... Bäzner H, Krauss JK, Hennerici MG, Bauer MF. Clinical and molecular findings in a patient with a ...

NGSANE: a lightweight production informatics framework for high-throughput data analysis.

PubMed

Buske, Fabian A; French, Hugh J; Smith, Martin A; Clark, Susan J; Bauer, Denis C

2014-05-15

The initial steps in the analysis of next-generation sequencing data can be automated by way of software 'pipelines'. However, individual components depreciate rapidly because of the evolving technology and analysis methods, often rendering entire versions of production informatics pipelines obsolete. Constructing pipelines from Linux bash commands enables the use of hot swappable modular components as opposed to the more rigid program call wrapping by higher level languages, as implemented in comparable published pipelining systems. Here we present Next Generation Sequencing ANalysis for Enterprises (NGSANE), a Linux-based, high-performance-computing-enabled framework that minimizes overhead for set up and processing of new projects, yet maintains full flexibility of custom scripting when processing raw sequence data. Ngsane is implemented in bash and publicly available under BSD (3-Clause) licence via GitHub at https://github.com/BauerLab/ngsane. Denis.Bauer@csiro.au Supplementary data are available at Bioinformatics online.

Molecular dynamics study of the structure and interparticle interactions of polyethylene glycol-conjugated PAMAM dendrimers.

PubMed

Lee, Hwankyu; Larson, Ronald G

2009-10-08

We performed molecular dynamics (MD) simulations of one or two copies of polyethylene glycol of molecular weight 550 (PEG550) and 5000 (PEG5000) daltons, conjugated to generation 3 (G3) to 5 (G5) polyamidoamine (PAMAM) dendrimers with explicit water using a coarse-grained model. We found the radii of gyration of these dendrimer-PEG molecules to be close to those measured in experiments by Hedden and Bauer (Hedden , R. C. ; Bauer , B. J. Macromolecules 2003 , 36 , 1829.). Densely grafted PEG ligands (>50% of the dendrimer surface) extend like brushes, with layer thickness in agreement with theory for starlike polymers. Two dendrimer-PEG complexes in the box drift away from each other, indicating that no aggregation is induced by either short or long PEG chains, conflicting with a recent view that the cytotoxicity of some PEGylated particles might be due to particle aggregation for long PEG lengths.

Prolotherapy: An Effective Treatment for Low Back Pain?

MedlinePlus

... pain? Is prolotherapy an effective treatment for chronic low back pain? Answers from Brent A. Bauer, M.D. Prolotherapy is ... reduced pain. Studies of prolotherapy in people with low back pain have had mixed results. A combination of prolotherapy ...

Can Glucosamine Supplements Protect My Knee Cartilage from Osteoarthritis?

MedlinePlus

... Can glucosamine supplements protect my knee cartilage from osteoarthritis? Answers from Brent A. Bauer, M.D. Study results on this question have ... build cartilage. The most common type of arthritis, osteoarthritis wears away the slick cartilage that covers the ...

Ear discharge

MedlinePlus

... swabs or other small objects into the ear Middle ear infection Other causes of ear discharge include: Eczema ... tube surgery - what to ask your doctor Images Ear anatomy Eardrum repair - series References Bauer CA, Jenkins HA. Otologic symptoms and syndromes. In: Flint PW, Haughey BH, Lund V, et ...

Teaching and Learning. IDRA Focus.

ERIC Educational Resources Information Center

IDRA Newsletter, 1997

1997-01-01

This theme issue includes four articles that focus on teaching and learning strategies to benefit all students, including limited-English-proficient, minority, economically disadvantaged, and at-risk students. "Would You Read Me a Story?: In Search of Reading Strategies That Work for the Early Childhood Classroom" (Hilaria Bauer)…

Neural Extensions to Robust Parameter Design

DTIC Science & Technology

2010-09-01

different ANNs to classify a winner in an NBA basketball game based simply on box score data. The results obtained from these authors showed remarkable......27-29, 2009. Loeffelholz, B.J., Bednar, E., & Bauer, K.W. (2009). “Predicting NBA games using neural networks,” Journal of Quantitative Analysis

Fungal spores as potential ice nuclei in fog/cloud water and snow

NASA Astrophysics Data System (ADS)

Bauer, Heidi; Goncalves, Fabio L. T.; Schueller, Elisabeth; Puxbaum, Hans

2010-05-01

INTRODUCTION: In discussions about climate change and precipitation frequency biological ice nucleation has become an issue. While bacterial ice nucleation (IN) is already well characterized and even utilized in industrial processes such as the production of artificial snow or to improve freezing processes in food industry, less is known about the IN potential of fungal spores which are also ubiquitous in the atmosphere. A recent study performed at a mountain top in the Rocky Mountains suggests that fungal spores and/or pollen might play a role in increased IN abundance during periods of cloud cover (Bowers et al. 2009). In the present work concentrations of fungal spores in fog/cloud water and snow were determined. EXPERIMENTAL: Fog samples were taken with an active fog sampler in 2008 in a traffic dominated area and in a national park in São Paulo, Brazil. The number concentrations of fungal spores were determined by microscopic by direct enumeration by epifluorescence microscopy after staining with SYBR Gold nucleic acid gel stain (Bauer et al. 2008). RESULTS: In the fog water collected in the polluted area at a junction of two highly frequented highways around 22,000 fungal spores mL-1 were counted. Fog in the national park contained 35,000 spores mL-1. These results were compared with cloud water and snow samples from Mt. Rax, situated at the eastern rim of the Austrian Alps. Clouds contained on average 5,900 fungal spores mL-1 cloud water (1,300 - 11,000) or 2,200 spores m-3 (304 - 5,000). In freshly fallen snow spore concentrations were lower than in cloud water, around 1,000 fungal spores mL-1 were counted (Bauer et al. 2002). In both sets of samples representatives of the ice nucleating genus Fusarium could be observed. REFERENCES: Bauer, H., Kasper-Giebl, A., Löflund, M., Giebl, H., Hitzenberger, R., Zibuschka, F., Puxbaum, H. (2002). The contribution of bacteria and fungal spores to the organic carbon content of cloud water, precipitation and aerosols. Atmos. Res. 64, 109-119. Bauer, H., Schueller, E., Weinke, G. Berger, A., Hitzenberger, R., Marr, I.L., Puxbaum, H. (2008). Significant contributions of fungal spores to the organic carbon and to the aerosol mass balance of the urban atmospheric aerosol. Atmos. Environ. 42, 5542-5549. Bowers, R.M., Lauber, C.L., Wiedinmyer, C., Hamady, M., Hallar, A.G., Fall, R., Knight, R., Fierer, N. (2009). Characterization of airborne microbial communities at a high-elevation site and their potential to act as atmospheric ice nuclei. Appl. Environ. Microbiol: 75, 5121-5130.

Cultured Inquiry

ERIC Educational Resources Information Center

Scheppler, Judith A.; Sethakorn, Nan; Styer, Susan

2003-01-01

The Kirby-Bauer assay, also called the disc diffusion assay, is a standard procedure used in clinical laboratories to test the susceptibility of patients' bacterial isolates to antibiotics. In the assay, the bacteria are swabbed onto an agar plate, and paper discs impregnated with antibiotics are placed on the agar. The antibiotic diffuses from…

Methods for Assessing Sleep in Children with Autism Spectrum Disorders: A Review

ERIC Educational Resources Information Center

Hodge, Danelle; Parnell, Andrea M. N.; Hoffman, Charles D.; Sweeney, Dwight P.

2012-01-01

A literature review completed by Bauer and Blunden (2008) determined that compared to objective measures, subjective assessments of sleep for typically developing children (e.g., parental reports) were of limited utility. No comparable literature review has been undertaken to determine whether subjective measures are appropriate for assessing…

Effects of Quality of Instruction on Student Vocabulary and Comprehension during Read Alouds

ERIC Educational Resources Information Center

Baker, Doris Luft; Santoro, Lana; Biancarrosa, Gina; Baker, Scott K.

2015-01-01

Reading aloud to students in preschool and the early grades is ubiquitous in American classrooms and considerable research has been conducted on read aloud practices (Karweit & Wasik, 1996; Morrow & Brittain, 2003; Van Kleeck, Stahl, & Bauer, 2003; Varelas & Pappas, 2006; Wilkinson & Silliman, 2000). Compelling evidence…

AFRC2017-0092-07

NASA Image and Video Library

2017-04-25

The Fiber Optic Sensing System team includes in the front from left Nick Finks, Ryan Warner, Patrick Chan and Paul Bean. In the back row from left are Shideh Naderi, Jeff Bauer, Allen Parker, Frank Pena and Nathan Perreau. Lance Richards, Anthony Piazza and Phil Hamory are current FOSS team members who are not pictured.

Automated Combinatorial Chemistry in the Organic Chemistry Majors Laboratory

ERIC Educational Resources Information Center

Nichols, Christopher J.; Hanne, Larry F.

2010-01-01

A multidisciplinary experiment has been developed in which students each synthesize a combinatorial library of 48 hydrazones with the aid of a liquid-handling robot. Each product is then subjected to a Kirby-Bauer disk diffusion assay to assess its antibacterial activity. Students gain experience working with automation and at the…

Health Needs of Transition-Aged Youth: Feature Issue of IMPACT.

ERIC Educational Resources Information Center

Tommet, Pat, Ed.; And Others

1994-01-01

This feature issue explores health needs of youth with disabilities as they make the transition from child to adult roles. "School Health Services: Supporting Students with Special Health Needs" (Dee K. Bauer) describes the role of the special needs nurse on multidisciplinary teams in Multnomah County (Oregon) schools. Two articles deal with…

’What’ and ’Where’ in Visual Attention: Evidence from the Neglect Syndrome

DTIC Science & Technology

1992-01-01

representations of the visual world, visual attention, and object representations. 24 Bauer, R. M., & Rubens, A. B. (1985). Agnosia . In K. M. Heilman, & E...visual information. Journal of Experimental Psychology: General, 1-1, 501-517. Farah, M. J. (1990). Visual Agnosia : Disorders of Object Recognition and

Physics of High-Temperature Air. Part. 2. Applications

DTIC Science & Technology

1990-08-01

water-soluble material such as sea salt, and biotic particles such as bacteria and fine plant debris, as well as water and ice particles. Table 7.3...150 180 1-F .41.W-32 4 o Figure 7.5. Scattering from Distributions of Water Droplets (of mean radius 4 gmo ) at Different Wavelengths. (Source: Bauer

Cortisol and Children's Adjustment: The Moderating Role of Sympathetic Nervous System Activity

ERIC Educational Resources Information Center

El-Sheikh, Mona; Erath, Stephen A.; Buckhalt, Joseph A.; Granger, Douglas A.; Mize, Jacquelyn

2008-01-01

We examined relations among cortisol, markers of sympathetic nervous system (SNS) activity (including salivary alpha-amylase and skin conductance level), and children's adjustment. We also tested the Bauer et al. ("Journal of Developmental and Behavioral Pediatrics," 23(2), 102-113, 2002) hypothesis that interactions between the SNS and cortisol…

The Midwest Research to Practice Conference in Adult and Continuing Education (East Lansing, Michigan, October 8-9, 1987).

ERIC Educational Resources Information Center

Levine, S. Joseph, Ed.; And Others

The following papers are included: "Facilitating Adult Learning in Graduate Programs" (Bauer); "Toward Synergistic Delivery of Adult Agricultural Education" (Cano, Miller); "Proposing a Needs Assessment Model for Academic Program Development" (Claus); "Preferred Learning Styles of University of Wisconsin External Degree Students and Their Impact…

Marketplace Impact | Transportation Research | NREL

Science.gov Websites

Marketplace Impact Marketplace Impact This is the December 2014 issue of the Transportation and Hydrogen Newsletter. An illustration showing the outside of an electric vehicle with some portion of the partnership with the private sector to maximize market impact. Illustration by Joshua Bauer/NREL Public

"Read the Text, as if!"The Reading Retention Strategy

ERIC Educational Resources Information Center

Divoll, Kent; Browning, Sandra

2013-01-01

Students do not always read what is expected in college courses (Berry, Cook, Hill, & Stevens, 2010; Phillips & Phillips, 2007; Sikorski et al., 2002) or they read to cram for an exam or quiz (Clump, Bauer, & Bradley, 2004). The Reading Retention Strategy (RRS) is designed to motivate students to read and assist students in…

Interrogating Meanings of Work in Children's Literature

ERIC Educational Resources Information Center

Wieland, Stacey M. B.; Bauer, Janell C.

2015-01-01

In this article, Wieland and Bauer discuss a teaching activity that helps students understand how meanings of work (MOW) are socially constructed through commonplace texts: children's books. The activity helps students consider how children's books shape future workers' understandings of what work is, what kinds of work are most…

History of emerald ash borer biological control

Treesearch

Juli R. Gould; Leah S. Bauer; Jian J. Duan; David Williams; Houping Liu

2015-01-01

The search for natural enemies of the emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in northeastern Asia, its native range, was initiated within a year of its discovery in the United States (Bauer et al., 2005, 2014). Although the official response to EAB’s invasion in both the United States and Canada...

The Vanishing Tetrad Test: Another Test of Model Misspecification

ERIC Educational Resources Information Center

Roos, J. Micah

2014-01-01

The Vanishing Tetrad Test (VTT) (Bollen, Lennox, & Dahly, 2009; Bollen & Ting, 2000; Hipp, Bauer, & Bollen, 2005) is an extension of the Confirmatory Tetrad Analysis (CTA) proposed by Bollen and Ting (Bollen & Ting, 1993). VTT is a powerful tool for detecting model misspecification and can be particularly useful in cases in which…

Web life: Faraday's Cage Is Where You Put Schrödinger's Cat

NASA Astrophysics Data System (ADS)

2012-01-01

Faraday's Cage Is Where You Put Schrödinger's Cat (FCIWYPSC) is a blog written by Cherish Bauer-Reich, who is pursuing a PhD in geophysics at the University of Minnesota while also working part-time as a research engineer at North Dakota State University (NDSU), some 250 miles away.

Can disc diffusion susceptibility tests assess the antimicrobial activity of engineered nanoparticles?

NASA Astrophysics Data System (ADS)

Kourmouli, Angeliki; Valenti, Marco; van Rijn, Erwin; Beaumont, Hubertus J. E.; Kalantzi, Olga-Ioanna; Schmidt-Ott, Andreas; Biskos, George

2018-03-01

The use of disc diffusion susceptibility tests to determine the antibacterial activity of engineered nanoparticles (ENPs) is questionable because their low diffusivity practically prevents them from penetrating through the culture media. In this study, we investigate the ability of such a test, namely the Kirby-Bauer disc diffusion test, to determine the antimicrobial activity of Au and Ag ENPs having diameters from 10 to 40 nm on Escherichia coli cultures. As anticipated, the tests did not show any antibacterial effects of Au nanoparticles (NPs) as a result of their negligible diffusivity through the culture media. Ag NPs on the other hand exhibited a strong antimicrobial activity that was independent of their size. Considering that Ag, in contrast to Au, dissolves upon oxidation and dilution in aqueous solutions, the apparent antibacterial behavior of Ag NPs is attributed to the ions they release. The Kirby-Bauer method, and other similar tests, can therefore be employed to probe the antimicrobial activity of ENPs related to their ability to release ions rather than to their unique size-dependent properties. [Figure not available: see fulltext.

Establishing Oobius agrili (Hymenoptera: Encyrtidae), the introduced egg parasitoid of emerald ash borer, in Michigan ash stands

Treesearch

Toby Petrice; F. William Ravlin; Leah S. Bauer; Therese M. Poland

2016-01-01

The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) is one of four parasitoid species from northeast Asia being released in regions of North America as part of a biological control program to manage the invasive emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) (Bauer et al...

A Classroom Demonstration of Garlic Extract and Conventional Antibiotics' Antimicrobial Activity

ERIC Educational Resources Information Center

Ekunsanmi, Toye J.

2005-01-01

The Kirby-Bauer method is regularly used to test bacterial susceptibility to antibiotics, and is often employed in the classroom for teaching this concept. In this exercise, additional materials and instructions were given to students for the preparation of garlic extract and loading on blank BBL paper discs. They were further instructed to test…

A resolution urging the Government of the Islamic Republic of Iran to immediately and unconditionally release Sarah Shourd, Joshua Fattal, and Shane Bauer on humanitarian grounds.

THOMAS, 111th Congress

Sen. Boxer, Barbara [D-CA

2010-08-02

Senate - 08/02/2010 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

Biochemical genetic variation in the Family Simuliidae: electrophoretic identification of the human biter in the isomorphic Simulium jenningsi group

Treesearch

Bernie May; Leah S. Bauer; Robert L. Vadas; Jeffrey Granett

1977-01-01

This paper describes inter- and intraspecific protein variation in the 3 closely related species of the Simulium jenningsi black fly group, S. jenningsi Malloch, S. Nyssa Stone and Snoddy, and S. n. sp. P. Snoddy and Bauer. Variation is described at single loci coding for the enzymes,...

Health Communication: A Future Direction for Instructional Communication Research. Forum: The Future of Instructional Communication

ERIC Educational Resources Information Center

Donovan, Erin; Love, Brad; Mackert, Michael; Vangelisti, Anita; Ring, David

2017-01-01

As ways that communication scholars can prepare students to meet challenges and transform society are considered, for the greater good, the authors argue that it is essential to consider the realm of health communication (Morreale, Valenzano, & Bauer, 2016). The authors focus on a growing need for rigorous research as a cornerstone of…

Do the Low Levels of Reading Course Material Continue? An Examination in a Forensic Psychology Graduate Program

ERIC Educational Resources Information Center

Clump, Michael A.; Doll, Jason

2007-01-01

Clump, Bauer, and Bradley (2004) and Burchfield and Sappington (2000) previously found extremely low levels of reading in undergraduate psychology courses. The current study investigated whether these low levels of reading are also found with graduate students, or if this value is altered by only investigating individuals who show continued…

Adaptation of the Attitude toward the Subject of Chemistry Inventory (ASCI) into Turkish

ERIC Educational Resources Information Center

Sen, Senol; Yilmaz, Ayhan; Temel, Senar

2016-01-01

Developing an attitude influential in individuals' behaviours and related with academic achievement is a concept whose development science educators consider important. This research aims to adapt the 8-item Attitude toward the Subject of Chemistry Inventory (ASCI)--which was developed by Bauer (2008) and revised by Xu and Lewis (2011)--into…

Missouri Assessment Program (MAP), Spring 2000: Intermediate Communication Arts, Released Items, Grade 7.

ERIC Educational Resources Information Center

Missouri State Dept. of Elementary and Secondary Education, Jefferson City.

This document deals with testing in intermediate communication arts for seventh graders in Missouri public schools. The document contains the following items from the Session 1 Test Booklet: "Swimming in Snow" (Diana C. Conway) (Items 1, 2, and 5); "Discovery" (Marion Dane Bauer) (Item 13); writing prompt; and a writer's…

Summary of air pollution impacts on forests in the Mexico City air basin

Treesearch

Mark E. Fenn; L.I. de Bauer; Tomás Hernández-Tejeda

2002-01-01

Oxidant air pollution symptoms were first reported in bioindicator plants in the Mexico City Air Basin (MCAB) in 1971 (de Bauer 1972). Classic injury symptoms on well-known bioindicator plants strongly supported the presumption that symptoms were caused by photochemical oxidants, of which ozone (O3) is the primary pollutant. Symptoms in indicator...

Explaining Secondary School Students' Attitudes towards Chemistry in Chile

ERIC Educational Resources Information Center

Montes, L. H.; Ferreira, R. A.; Rodríguez, C.

2018-01-01

Research into attitudes towards chemistry in Latin America and indeed towards science in general is very limited. The present study aimed to adapt and validate a shortened version of Bauer's Attitude toward the Subject of Chemistry Inventory version 2 (ASCIv2) for use in a Latin American context. It also explored attitudes towards chemistry of…

Modeling Antimicrobial Activity of Clorox(R) Using an Agar-Diffusion Test: A New Twist On an Old Experiment.

ERIC Educational Resources Information Center

Mitchell, James K.; Carter, William E.

2000-01-01

Describes using a computer statistical software package called Minitab to model the sensitivity of several microbes to the disinfectant NaOCl (Clorox') using the Kirby-Bauer technique. Each group of students collects data from one microbe, conducts regression analyses, then chooses the best-fit model based on the highest r-values obtained.…

Rail gun performance and plasma characteristics due to wall ablation

NASA Technical Reports Server (NTRS)

Ray, P. K.

1986-01-01

The experiment of Bauer, et al. (1982) is analyzed by considering wall ablation and viscous drag in the plasma. Plasma characteristics are evaluated through a simple fluid-mechanical analysis considering only wall ablation. By equating the energy dissipated in the plasma with the radiation heat loss, the average properties of the plasma are determined as a function of time.

Teachers' Degree of Instructional Technology Use and Its Effect on the Mathematics Achievement of Students in Secondary Schools

ERIC Educational Resources Information Center

Dutton, Valencia K.

2012-01-01

Integrating computer technology began as a poorly planned idea where teachers were inadequately trained in how to integrate the use of technology into the classroom (Wright & Shade, 1994 as cited in Bauer & Kenton, 2005). As the use of technology continues to advance around the world, the impact of the new technology equipment and…

Marketing Terror: Effects of Anti-Messaging on GSPC Recruitment (Strategic Insights, Volume V, Issue 8, November 2006)

DTIC Science & Technology

2006-11-01

Raymond A. Bauer, “The Initiative of the Audience,” in Journal of Advertising Research (June 1963), 2. 47. Boyd and Levy, Op. Cit., 25. 48. Ibid...Initiative of the Audience,” Journal of Advertising Research (June 1963). Boyd, Harper W. Jr., and Sidney J. Levy, Promotion: A Behavioral View (Englewood

Burlap bands as a sampling technique for green anoles (Anolis carolinensis) and other reptiles commonly found in tree boles

Treesearch

Scott Horn; James L. Hanula

2006-01-01

A variety of methods have been used to study lizard populations including rubber bands, active searching and noosing (Campbell and Christman 1982; Karns 1986; Simmons 1987), pitfall traps (Fair and Henke 1997; Moseley 2004; Sutton et al. 1999), glue boards (Bauer and Sadlier 1992; Downes and Borges 1998; Durtsche 1996; Moseley 2004;...

Definition of Research Needs to Address Airport Pavement Distress in Cold Regions

DTIC Science & Technology

1989-05-01

2318 RODNEY A. 03/04/85 ALLIANCE AIRPORT PO DRAWER D ALLIANCE NE 69301 ACE NC BAUER 308-762-5400 WOLFGANG 03/25/85 HALL COUNTY REGIONAL AIRPORT ROUTE 3...NW WINTER 206-346-7380 JEFF 03/05/85 SEA-TAC INT’L. AIRPORT SEATTLE WA 98188 ANN MW KRAUSE 206-433-5410 ART 03/05/85 GRANT COUNTY AIRPORT TERMINAL

Neuropsychological Component of Imagery Processing

DTIC Science & Technology

1991-01-25

and von Bonin, G. (1951). The Isocortex of Man. Urbana, IL: University of Illinois Press. Bauer, R. M., and Rubens, A. B. (1985). Agnosia . In K. M...Apperceptive agnosia : the specification and description of constructs. In Humphreys, G. W., and Riddoch, M. J. (1987a) (Eds.). Visual Object Processing: A...visual processing: agnosias , achromatopsia, Balint’s syndrome and related difficulties of orientation and construction. In M.-M. Mesulam (Ed

Neuropsychological Components of Object Identification

DTIC Science & Technology

1992-01-10

Man. Urbana, IL: University of Illinois Press. Bauer, R. M., and Rubens, A. B. (1985). Agnosia . In K. M. Heilman and E. Valenstein (Eds.), Clinical...J. (1987). Apperceptive agnosia : the specification and description of constructs. In Humphreys, G. W., and Riddoch, M. J. (1987a) (Eds.). Visual... agnosias , achromatopsia, Balint’s syndrome and related difficulties of orientation and construction. In M.-M. Mesulam (Ed.), Principles of Behavioral

Bridges to the Future: Building Linkages for Institutional Research. North East Association for Institutional Research Annual Conference Proceedings (27th, Pittsburgh, PA, November 4-7, 2000).

ERIC Educational Resources Information Center

North East Association for Institutional Research.

This document contains papers, summaries of panel presentations, and work share meetings from the annual conference of the North East Association for Institutional Research. The papers are: (1) "The Influence of Personality Traits, Pre-College Characteristics, and Co-Curricular Experiences on College Outcomes" (Karen W. Bauer); (2)…

Equation of State of Aluminum-Iron Oxide-Epoxy Composite

DTIC Science & Technology

2007-07-01

which case shock velocities were measured in the samples and aluminum, copper, or polymethyl methacrylate PMMA donor material, using piezoelectric pins...which piezoelectric polyvinylidene fluoride PVDF stress gauges were used to measure the input and propagated stress wave profiles in the sample and...instrumented with Bauer piezoelectric polyvinylidene fluoride PVDF stress gauges6 obtained from Ktech Corporation, Albuquerque, NM. The gauges were mounted on

Bauer ketones 23 and 24 from Echinacea paradoxa var. paradoxa inhibit lipopolysaccharide-induced nitric oxide, prostaglandin E2 and cytokines in RAW 264.7 mouse macrophages

USDA-ARS?s Scientific Manuscript database

Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In our study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were scr...

The Concreteness Effect and the Bilingual Lexicon: The Impact of Visual Stimuli Attachment on Meaning Recall of Abstract L2 Words

ERIC Educational Resources Information Center

Farley, Andrew P.; Ramonda, Kris; Liu, Xun

2012-01-01

According to the Dual-Coding Theory (Paivio & Desrochers, 1980), words that are associated with rich visual imagery are more easily learned than abstract words due to what is termed the concreteness effect (Altarriba & Bauer, 2004; de Groot, 1992, de Groot et al., 1994; ter Doest & Semin, 2005). The present study examined the effects of attaching…

75 FR 37759 - Initiation of Antidumping and Countervailing Duty Administrative Reviews and Requests for...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-30

...... 5/1/09-4/30/10 Alcatel Vacuum Technology Audi AG AVIAC Avio (formerly known as FiatAvio) Bosch... Audi AG Avio (formerly known as FiatAvio) BAUER Maschinen GmbH Bosch Rexroth AG BSH Bosch und Siemens... Bearings and Parts Thereof, A-475-201.... 5/1/09-4/30/10 Audi AG Avio, S.p.A. (formerly known as FiatAvio...

Targeted Delivery of Therapeutic Oligonucleotides for the Treatment of Prostate Cancer

DTIC Science & Technology

2004-05-01

AD Award Number: DAMD17-01-1-0090 TITLE: Targeted Delivery of Therapeutic Oligonucleotides for the Treatment of Prostate Cancer PRINCIPAL...independence and chemoresistance are the major obstacles in the treatment of patients with advanced prostate cancer (Denis & Murphy, 1993; Oh & Kantoff...independence and chemoresistance in prostate cancer (McDonnell et al., 1992; Colombel et al., 1993; Berchem et al., 1995; Raffo et al., 1995; Bauer et al

Response Sensitivity of Typical Aircraft Jet Engine Fan Blade-Like Structures to Bird Impacts.

DTIC Science & Technology

1982-05-01

AIRCRAFT ENGINE BU--ETC F/G 21/5 RESPONSE SENSITIVITY OF TYPICAL AIRCRAFT JET ENGINE FAN BLADE -L...SENSITIVITY OF TYPICAL AIRCRAFT JET ENGINE FAN BLADE -LIKE STRUCTURES TO BIRD IMPACTS David P. Bauer Robert S. Bertke University of Dayton Research...COVERED RESPONSE SENSITIVITY OF TYPICAL AIRCRAFT FINAL REPORT JET ENGINE FAN BLADE -LIKE STRUCTURES Oct. 1977 to Jan. 1979 TO BIRD IMPACTS s.

Integrating Requirements Engineering, Modeling, and Verification Technologies into Software and Systems Engineering

DTIC Science & Technology

2007-10-28

Software Engineering, FASE󈧉, volume 3442 of Lecture Notes in Computer Science, pages 175--189. Springer, 2005. Andreas Bauer, Martin Leucker, and Jonathan ...of Personnel receiving masters degrees NAME Markus Strohmeier Gerrit Hanselmann Jonathan Streit Ernst Sassen 4Total Number: Names of personnel...developed and documented mainly within the master thesis by Jonathan Streit [Str06]: • Jonathan Streit. Development of a programming language like tem

Burlap bands as a sampling technique for green anoles (Anolis carolinensis) and other reptiles commonly found on tree boles

Treesearch

Scott Horn; James L. Hanula

2006-01-01

A variety of methods have been used to study lizard populations including rubber bands, active searching and noosing (Campbell and Christman 1982; Karns 1986; Simmons 1987), pitfall traps (Fair and Henke 1997; Moseley 2004; Sutton et al. 1999), glue boards (Bauer and Sadlier 1992; Downes and Borges 1998; Durtsche 1996; Moseley 2004; Whiting 1998), extraction by hook (...

Synthesis and Mass Spectra of Butenyltin Compounds

DTIC Science & Technology

1989-03-01

activities or operations. One instance of this concern has focused on the Navy’s use of tributyltin compounds as antifoulants on ships’ hulls. Such...butene, and 1-chloro- 2-butene were obtained from Pfaltz & Bauer (Waterbury, CT). Resublimed magne- sium chips, tetrabutyltin and tributyltin bromide...preferential elimination of R minus R to form RSn ’from R3Sn + The fragmentation patterns of tributyltin bromide and tributenyltin bromides are dominated

Task Order Final Report for the Period 20 January 2003 to 19 January 2005 (Northrop Grumman)

DTIC Science & Technology

2005-04-01

34Nonlinear optical characterization of retinal molecules," Laser and Noncoherent Light Ocular Effects: Epidemiology, Prevention, and Treatment III, Bruce E...BIOEFFECTS DIVISION OPTICAL RADIATION BRANCH 2624 LOUIS BAUER DRIVE BROOKS CITY-BASE TX 78235 April2005 Approved for public release, distribution...SPONSORIMONITOR’S ACRONYM(S) Air Force Research Laboratory AFRL/HE Human Effectiveness Directorate, Directed Energy Bioeffects Division Optical Radiation

The Beginnings of Aeromedical Acceleration Research

DTIC Science & Technology

1981-09-30

matiere qui sera la limite des per- formance acrobatique de I’oiseau artificiel , mais bien la resistance physiologique de I’homme qui en est le...3. Bauer, L. H. 1926. Aviation Medizin. Publisher Williams and Wilkins, Baltimore. 4. Bleriot, L, 1922. L’oiseau artificiel . L’Aerophile 19:20, 15...Director, Defense Intelligence Agency, (Code DR), Washington, DC 20301 3 Commander, Naval Air Test Center, Patuxent River, MD 20670 2

Quantiative reliability of the Migdal-Eliashberg theory for strong coupling superconductors

NASA Astrophysics Data System (ADS)

Bauer, Johannes; Han, Jong; Gunnarsson, Olle

2012-02-01

The Migdal-Eliashberg (ME) theory for strong electron-phonon coupling and retardation effects of the Morel-Anderson type form the basis for the quantitative understanding of conventional superconductors. The validity of the ME theory for values of the electron-phonon coupling strength λ>1 has been questioned by model studies. By distinguishing bare and effective parameters, and by comparing the ME theory with the dynamical mean field theory (DMFT), we clarify the range of applicability of the ME theory. Specifically, we show that ME theory is very accurate as long as the product of effective parameters, λφph/D, where φph is an appropriate phonon scale and D an electronic scale, is small enough [1]. The effectiveness of retardation effects is usually considered based on the lowest order diagram in the perturbation theory. We analyze these effects to higher order and find modifications to the usual result for the Coulomb pseudo-potential &*circ;. Retardation effects are weakened due to a reduced effective bandwidth. Comparison with the non-perturbative DMFT corroborates our findings [2]. [4pt] [1] J Bauer, J E Han, and O Gunnarsson, Phys. Rev. B. 84, 184531 (2011).[0pt] [2] J Bauer, J E Han, and O Gunnarsson, in preparation (2011).

Characters and clues: Factors affecting children’s extension of knowledge through integration of separate episodes

PubMed Central

Bauer, Patricia J.; King, Jessica E.; Larkina, Marina; Varga, Nicole L.; White, Elizabeth A.

2012-01-01

Children build up knowledge about the world and also remember individual episodes. How individual episodes during which children learn new things become integrated with one another to form general knowledge is only beginning to be explored. Integration between separate episodes is called on in educational contexts and in everyday life as a major means of extending knowledge and organizing information. Bauer and San Souci (2010) provided an initial demonstration that 6-year-olds extend their knowledge by integrating between separate but related episodes; the episodes shared a high level of surface similarity. Experiments 1A and 1B of the current research were tests of integration under low and high levels of surface similarity, respectively. In Experiment 1A, when surface similarity of the episodes was low, 6-year-olds integrated between passages of text, yet their performance was not as robust as observed previously. In Experiment 1B, when surface similarity of the episodes was high, a replication of Bauer and San Souci’s results was observed. In Experiment 2, we tested whether a “hint” to consult the information learned in the passages improved performance even when surface level similarity was low. The hint had a strong facilitating effect. Possible mechanisms of integration between separate yet related episodes are discussed. PMID:22153911

Unmanned. Evaluation of Bauer High Pressure Breathing Air P-5 Purification System

DTIC Science & Technology

1991-08-01

suspended in the compressed air . The molecular sieve is made to adsorb oil and water vapors. The second cylinder uses cartridge No. 058825 and is a...during compressor start up. This provides for optimum filtering, moisture separation and prevents compressed air return from the charged air storage...reciprocating, air -cooled unit. The compressor is rated to deliver 20 cfm of free air compressed to 5000 psig. - .. .. . .. ’,= .• .. . .. . -. . I

Is Visual Imagery Really Visual? Overlooked Evidence from Neuropsychology.

DTIC Science & Technology

1987-08-07

the study of imagery. British Journal of Psychology, 47 101-114 Bauer,R. M.. & Rubens. A B (1985). Agnosia In K. M. Heilman & E. Valenstein (Ed Clinical...Neuropsychology. New York: Oxford University Press. 2nd edition. Beauvois. M.F . & Saillant. B (1985) Optic aphasia for colours and colour agnosia A...integrative visual agnosia . Brain, Roland. P.E. (1982). Cortical regulation of selective attention in man. Journal of Neuroohysiology, 48. 1059-1078

Expedition 41 Preflight

NASA Image and Video Library

2014-09-23

Expedition 41 Flight Engineer Barry Wilmore gets his hair cut at the Cosmonaut Hotel, on Tuesday, Sept. 23, 2014, at the Baikonur Cosmodrome in Kazakhstan. Launch of the Soyuz is scheduled for Sept. 26 and will send Barry Wilmore of NASA, Soyuz Commander Alexander Samokutyaev of the Russian Federal Space Agency (Roscosmos), and Flight Engineer Elena Serova of Roscosmos to the International Space Station for a five and a half month stay. Photo Credit: (NASA/Dr. Peter Bauer)

Enhancing Interrogation: Advancing a New Agenda

DTIC Science & Technology

2009-01-01

cloaked in righteousness, and would make the American people less safe.”16 His clear message, delivered in an earli- er Fox News interview, is that...Scalia, a fan of Fox network’s hit drama 24, has championed the show’s federal agent protagonist, Jack Bauer, who regularly saves the nation by...with one based on “submission through humiliation and cruelty .”37 Even more damaging, Soufan contended, was the exclusion of FBI agents from further

Mission Command: The Historical Roots of Mission Command in the US Army

DTIC Science & Technology

2015-05-21

Bauer, Zachary Taylor: Soldier, Planter, Statesman, of the Old Southwest (Baton Rouge, LA : Louisiana State University Press, 1985), 1. General...Battle of Buena Vista , he observed the battle from so close that his coat ended up riddled with holes from grape shot.25 General Taylor created a...1846 report to Colonel Joseph Totten he describes his observations of the battle of Palo Alto and Resaca De La Palma. Scarritt served temporarily

The Future Is Now: The Role of Institutional Research in Campus Transformation: Proceedings of the Annual Conference of the North East Association for Institutional Research (25th, Philadelphia, Pennsylvania, November 14-17, 1998).

ERIC Educational Resources Information Center

North East Association for Institutional Research.

This proceedings document is comprised of the 17 papers, panel presentations, and work shares presented at a 1998 conference on institutional research. The papers are: (1) "Description of the UDAES Project: A Study of Undergraduate Academic Experiences" (Karen W. Bauer); (2) "Transforming Your Campus: Mixed Methodology in Institutional Research"…

Enhancement of the Efficacy of Conventional Anticancer Compounds through the Repression of SNAI Proteins in Aggressive Breast Cancer Cells

DTIC Science & Technology

2012-09-01

selected a 40-bp sequence from the human vitamin D3 receptor gene promoter that has two SLUG binding E2-box (5-CACCTG-3/3-CAG- GTG -5) sequences (Fig...131, 1877–1885 39. Yang, A. D., Camp, E. R., Fan, F., Shen, L., Gray , M. J., Liu, W., Somcio, R., Bauer, T. W., Wu, Y., Hicklin, D. J., and Ellis, L

Modeling of Surface Thermodynamics and Damage Thresholds in the IR and THz Regime

DTIC Science & Technology

2007-01-01

Conference on Optical Interactions with Tissue and Cells [18th] Held in San Jose, California on January 22-24, 2007 To order the complete compilation report...United States; c Air Force Reasearch Lab, Human Effectivness Directorate Optical Branch, 2624 Louis Bauer Drive, San Antonio, TX, United States...equation (radial and axial) in a biological system construct. Tissues are represented as multi-layer structures, with optical and thermal properties

Prevalence of methicillin resistant Staphylococcus aureus [MRSA] colonization or carriage among health-care workers.

PubMed

Pathare, Nirmal A; Asogan, Harshini; Tejani, Sara; Al Mahruqi, Gaitha; Al Fakhri, Salma; Zafarulla, Roshna; Pathare, Anil V

2016-01-01

In Oman, the prevalence of health care associated methicillin resistant Staphylococcus aureus [HA-MRSA] is unknown. Therefore, to estimate the prevalence of HA-MRSA, we collected nasal swabs and swabs from cell phones on sterile polyester swabs and immediately inoculated on the mannitol salt agar containing oxacillin from medical students and hospital health care providers. Antibiotic susceptibility testing of the isolates was then performed using the Kirby Bauer's disc diffusion method. Additionally, a brief survey questionnaire was used to acquire demographic data. Amongst the 311 participants enrolled, nasal colonization with HA-MRSA was found in 47 individuals (15.1%, 95% confidence interval [CI]=11.1%, 19.1%). HA-MRSA was also isolated from the cell phone surfaces in 28 participants (9.0%, 95% CI=8.6%, 9.3%). 5 participants (1.6%) showed positive results both from their nasal swabs and from their cell phones. Antibiotic resistance to erythromycin [48%] and clindamycin [29%] was relatively high. 9.3% HA-MRSA isolates were vancomycin resistant [6.6% nasal carriage]. There was no statistically significant correlation between HA-MRSA isolates and the demographic characteristics or the risk factors namely gender, underlying co-morbidities like diabetes, hypertension, skin/soft tissue infections, skin ulcers/wounds, recent exposure to antibiotics, or hospital visits (p>0.05, Chi-square test). Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

The Linguistic Core Approach to StructuredTranslation and Analysis of Low Resource Languages

DTIC Science & Technology

2017-09-02

grammars from no training data and partial training data (as given by GFL). We are now anno - tating GFL for English, Portuguese, Chinese and...translation. In Proc. EMNLP, 2014. [20] F. Drewes, H.- J . Kreowski, and A. Habel. Hyperedge replacement graph grammars. Handbook of Graph Grammars, 1:95–162...tory, Jena, 2015. [41] B. Jones, J . Andreas, D. Bauer, K-M. Hermann, and K. Knight. Semantics- based machine translation with hyperedge replacement

Development of novel ash hybrids to introgress resistance to emerald ash borer into north American ash species

Treesearch

Jennifer L. Koch; David W. Carey; Mary E. Mason

2008-01-01

Currently, there is no evidence that any of the native North American ash species have any resistance to the emerald ash borer (EAB). This means that the entire ash resource of the eastern United States and Canada is at risk of loss due to EAB. In contrast, outbreaks of EAB in Asian ash species are rare and appear to be isolated responses to stress (Bauer et al. 2005,...

Reliability Growth and Its Applications to Dormant Reliability

DTIC Science & Technology

1981-12-01

ability to make projection about future reli- ability (Rof 9:41-42). Barlow and Scheuer Model. Richard E. Barlow and Ernest M. Sch~uvr, of the University...Reliability Growth Prediction Models," Operations Research, 18(l):S2-6S (January/February 1970). 7. Bauer, John, William Hadley, and Robert Dietz... Texarkana , Texas, May 1973. (AD 768 119). 10. Bonis, Austin J. "Reliability Growth Curves for One Shot Devices," Proceedings 1977 Annual Reliability and

Electrical and Thermal Effects of Rail Cladding in a Full-Scale Launcher

DTIC Science & Technology

1998-04-01

A. E. Zielinski , "Current and Heat Transport in the Cannon-Caliber Electromagnetic Gun Armature," Army Research Laboratory, ARL-MR-258, August...Laboratory AMSRL-CI-LP Technical Library 305 Aberdeen Prvg Grd, MD 21005-5066 Mr. Dave Bauer lAP Research, Incorporated 2763 Culver Avenue Dayton...TX 78759 Mr. Robert J. Taylor Lockheed Martin Vought Systems M/S: WT-21 P.O. Box 650003 Dallas, TX 75265-0003 Mr. Alex Zielinski U.S. Army

Tracing the history of submarine hydrothermal inputs and the significance of hydrothermal hafnium for the seawater budget - A combined Pb-Hf-Nd isotope approach

USGS Publications Warehouse

van de Flierdt, T.; Frank, M.; Halliday, A.N.; Hein, J.R.; Hattendorf, B.; Gunther, D.; Kubik, P.W.

2004-01-01

Secular variations in the Pb isotopic composition of a mixed hydrogenous-hydrothermal ferromanganese crust from the Bauer Basin in the eastern Equatorial Pacific provide clear evidence for changes in hydrothermal contributions during the past 7 Myr. The nearby Galapagos Rise spreading center provided a strong hydrothermal flux prior to 6.5 Ma. After 6.5 Ma, the Pb became stepwise more radiogenic and more similar to Equatorial Pacific seawater, reflecting the westward shift of spreading to the presently active East Pacific Rise (EPR). A second, previously unrecognized enhanced hydrothermal period occurred between 4.4 and 2.9 Ma, which reflects either off-axis hydrothermal activity in the Bauer Basin or a late-stage pulse of hydrothermal Pb from the then active, but waning Galapagos Rise spreading center. Hafnium isotope time-series of the same mixed hydrogenous-hydrothermal crust show invariant values over the past 7 Myr. Hafnium isotope ratios, as well as Nd isotope ratios obtained for this crust, are identical to that of hydrogenous Equatorial Pacific deep water crusts and clearly indicate that hydrothermal Hf, similar to Nd, does not travel far from submarine vents. Therefore, we suggest that hydrothermal Hf fluxes do not contribute significantly to the global marine Hf budget. ?? 2004 Elsevier B.V. All rights reserved.

Germination response of Hylocereus setaceus (Salm-Dyck ex DC: ) Ralf Bauer (Cactaceae) seeds to temperature and reduced water potentials.

PubMed

Simão, E; Takaki, M; Cardoso, V J M

2010-02-01

The germination response of Hylocereus setaceus seeds to isothermic incubation at different water potentials was analysed by using the thermal time and hydrotime models, aiming to describe some germination parameters of the population and to test the validity of the models to describe the response of the seeds to temperature and water potential. Hylocereus setaceus seeds germinated relatively well in a wide range of temperatures and the germination was rate limited from 11 to 20 degrees C interval and beyond 30 degrees C until 40 degrees C, in which the germination rate respectively shifts positively and negatively with temperature. The minimum or base temperature (T(b)) for the germination of H. setaceus was 7 degrees C, and the ceiling temperature varied nearly from 43.5 to 59 degrees C depending on the percent fraction, with median set on 49.8 degrees C. The number of degrees day necessary for 50% of the seeds to germinate in the infra-optimum temperature range was 39.3 degrees C day, whereas at the supra-optimum interval the value of theta = 77 was assumed to be constant throughout. Germination was sensitive to decreasing values of psi in the medium, and both the germinability and the germination rate shift negatively with the reduction of psi, but the rate of reduction changed with temperature. The values of base water potential (psi(b)) shift to zero with increasing temperatures and such variation reflects in the relatively greater effect of low psi on germination in supra optimum range of T. In general, the model described better the germination time courses at lower than at higher water potentials. The analysis also suggest that Tb may not be independent of psi and that psi(b(g)) may change as a function of temperature at the infra-otimum temperature range.

Evaluation of BAUER UTILUS 10 and TRIPLEX Purification Systems

DTIC Science & Technology

1993-08-01

of the test was to: A. Determine if the compressor and Purification System provides compressed air at the required pressures, flow rates, quality and...optimum filtering, moisture separation, third stage piston ring expansion/cylinder sealing and prevents compressed air return from the storage flasks to the...551 COMPRESSED AIR PLANTS AND SYSTEMS S9086-SY-STM-O0O PARA 551-4.2.2.1. 6. Navy Experimental Diving Unit Test Plan Number 93-01, Jan 93. 7. NAVSEAINST

Evaluation of Bauer K-20 Diesel Drive High Pressure Breathing Air Compressor

DTIC Science & Technology

1993-12-01

was to: A. Determine if the compressor and Purification System provides compressed air at the required pressures, flow rates, quality and cleanliness... compressed air return from the air storage flasks to the compressor during unit shut down. All four stages of the compressor are protected by safety...1993. 6. Naval Ships Technical Manual, S9086-SY-STM-0O0, Chapeter 551 1st Rev. I November 1987. Compressed Air Plants and Systems, para 551-4.2.21. 7

Residual Mosquito Barrier Treatments on U.S. Military Camouflage Netting in a Southern California Desert Environment

DTIC Science & Technology

2010-08-01

8 indicates the presence of natural breeding habitat tor wild Cv. tur.sali.s throughout the 28-day population sam- pling period in the desert study...the tnosquito surveillance period (Fig. 2), along with consistently high trap counts at the offsite trap, indicate that natural breeding sites for Cx...Tierarztl 2006: 119:421^. IB. Bauer B, Gitau D, Oloo FP, Karanja SM: Evaluation of a preliminary title to protect zero-grazed dairy cattle with

Long Pulse Homopolar Generator

DTIC Science & Technology

1988-08-01

AD-A205 452 AFWAL-TR-88-2045 LONG PULSE HOMOPOLAR GENERATOR Edward A. Knoth David P. Bauer lAP Research, Inc. 2763 Culver Avenue Dayton OH 45429-3723...TASK WORK UNIT ELEMENT NO. NO. NO ACCESSION NO. 61101F ILIR P3 01 11. TITLE (include Security Classiflcation) Long Pulse Homopolar Generator 12. PERSONAL...FIELD GROUP SUB-GROUP C6 6; y .- o- , -, ’, - 20 07 homopolar , high current, high power, high speed, generator, 19. ABIT!CT (Contkwe on rer if =ray and

An Experimental Investigation of Rise Times of Very Weak Shock Waves.

DTIC Science & Technology

1981-03-01

Supply, R & M No. 3659, London, Pallant , R. J. 1971. Walters, W. L. 7. Webb, D. R. B. Private Communications, March and May, 1977. 8. Rigaud, P. "Bang...Mediumn", Proc. Eleventh International Symposium on Shock Tubes and Waves, July 1977, pp. 82-90. 23. Hesselink, L. "An Experimental Investigation of...B. "Sonic Boom and Turbulence Interactions - Laboratory Measurements Compared with Theory", AIAA Paper 71-618, July 1971. 25. Bauer, A. B. "Sonic

Prevention of Trauma/Hemorrhagic Shock-Induced Mortality, Apoptosis, Inflammation and Mitochondrial Dysfunction Using IL-6 as a Resuscitation Adjuvant

DTIC Science & Technology

2011-12-01

infiltrating PMNs is not merely limited to organs that have been directly injured from trauma. Ischemia - reperfusion injury (which occurs after... injury by facilitating inflammatory cell adhesion in an animal model of myocardial ischemia - reperfusion [61,62]. Fabp2 and Fabp5 have been implicated in...Bauer A, Tweardy DJ (1998) Activation of STAT proteins following ischemia reperfusion injury demonstrates a distinct IL- 6 and G-CSF mediated profile

Sixth International Workshop on Laser Physics (LPHYS 97) Volume 8, No. 1

DTIC Science & Technology

1998-01-01

solution of the problem concerning the action of an ultrashort laser pulse on an elementary molecular sys- tem—molecular hydrogen ion H2—is of...2 summarize the dynamics of the system for a peak pulse intensity / = 1.3 x 1016 W/cm2. First, Fig. 2a shows the Coulomb explosion of a molecule. It...Ionization of He in Intense Laser Fields A. Becker and F H. M. Faisal 69 Coulomb Correction to the Volkov Solution J. Bauer 76 Photoelectron

Pseudo Bipolar Nickel-Cadmium Batteries Used as Filter Elements to Pulsed Current Loads

DTIC Science & Technology

1984-11-01

authors’ Thesis sub- I.it-ted in partiil fulfillment of the requirements for the M1aster of Science Degree at the Air Force In~stitute of Technology...capable of out- performing capacitors as power supply filters. Purpose This thesis investigated the use of nickel-cadmium batteries as filter elements...require extensive testing and diagnosis of many cells, far beyond the scope of this thesis . Further, Paul Bauer [13] asserts that accelerated testing is

Detection and Identification of Ciprofloxacin-Resistant Yersinia pestis Denaturing High-Performance Liquid Chromatography

DTIC Science & Technology

2003-07-01

analysis in hereditary breast and ovarian cancers . Hum. Mutat. 14:333– 339. 2. Bauer, A. W., W. M. Kirby, J. C. Sherris, and M. Turck. 1966. Antibiotic...Listeria monocytogenes lineage group classification by MAMA -PCR of the listeriolysin gene. Curr. Microbiol. 43:129–133. 17. Klein, B., G. Weirich...Germline and somatic mutation anal- yses in the DNA mismatch repair gene MLH3: evidence for somatic muta- tion in colorectal cancers . Hum. Mutat. 17:389–396

Surveillance of multidrug resistant uropathogenic bacteria in hospitalized patients in Indian

PubMed Central

Mishra, Monali Priyadarsini; Debata, Nagen Kumar; Padhy, Rabindra Nath

2013-01-01

Objective To record surveillance, antibiotic resistance of uropathogens of hospitalized patients over a period of 18 months. Methods Urine samples from wards and cabins were used for isolating urinary tract infection (UTI)-causing bacteria that were cultured on suitable selective media and identified by biochemical tests; and their antibiograms were ascertained by Kirby-Bauer's disc diffusion method, in each 6-month interval of the study period, using 18 antibiotics of five different classes. Results From wards and cabins, 1 245 samples were collected, from which 996 strains of bacteria belonging to 11 species were isolated, during April 2011 to September 2012. Two Gram-positive, Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), and nine Gram-negative bacteria, Acinetobacter baumannii, Citrobacter sp., Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis, Proteus vulgaris and Pseudomonas aeruginosa were isolated. Both S. aureus and E. faecalis were vancomycin resistant, and resistant-strains of all pathogens increased in each 6-month period of study. Particularly, all Gram-negatives were resistant to nitrofurantoin and co-trimoxazole, the most preferred antibiotics of empiric therapy for UTI. Conclusions Antibiograms of 11 UTI-causing bacteria recorded in this study indicated moderately higher numbers of strains resistant to each antibiotic studied, generating the fear of precipitating fervent episodes in public health particularly with bacteria, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae and S. aureus. Moreover, vancomycin resistance in strains of S. aureus and E. faecalis is a matter of concern. PMID:23620859

Molecular characterization and evaluation of the emerging antibiotic-resistant Streptococcus pyogenes from eastern India.

PubMed

Ray, Dipanwita; Saha, Somnath; Sinha, Sukanta; Pal, Nishith Kumar; Bhattacharya, Basudev

2016-12-12

Group A Streptococcus strains causing wide variety of diseases, recently became noticeable in eastern India, are not amenable to standard treatment protocol thus enhancing the possibility of disease morbidity by becoming antibiotic resistance. The association of Lancefield group A Streptococcal variation with degree of vir architectural diversity was evaluated using emm typing and restriction fragment length polymorphism analyses. The antibiotic sensitivity patterns were examined by modified Kirby-Bauer method of disk diffusion. Percentage calculations, 95% confidence interval and one-way ANOVA were used to assess differences in proportions. Our observations revealed 20 different emm types and 13 different HaeIII vir typing patterns. A 1.2 kb fragment was found in all HaeIII typing pattern. Fragments of 1.2 kb and 550 bp were conserved in majority of the isolates. HinfI digestion was found proficient in differentiating the strains of same vir typing patterns. Strong predominance of speC (85%) and speF (80%) genes have been observed encoding exotoxins production. 4 isolates were found to be erythromycin resistant and were of genotype emm49. High degree of tetracycline resistance was shown by 53.57% isolates which belonged to 12 different emm genotypes. These findings suggested that in addition to emm typing, sequential application of HaeIII and HinfI restriction enzymes in vir typing analysis is an effective tool for group A streptococcal molecular characterization associated with antibiotic resistance.

Testing all six person-oriented principles in dynamic factor analysis.

PubMed

Molenaar, Peter C M

2010-05-01

All six person-oriented principles identified by Sterba and Bauer's Keynote Article can be tested by means of dynamic factor analysis in its current form. In particular, it is shown how complex interactions and interindividual differences/intraindividual change can be tested in this way. In addition, the necessity to use single-subject methods in the analysis of developmental processes is emphasized, and attention is drawn to the possibility to optimally treat developmental psychopathology by means of new computational techniques that can be integrated with dynamic factor analysis.

August 6, 1996 Letter to Martin Bauer

EPA Pesticide Factsheets

This document may be of assistance in applying the Title V air operating permit regulations. This document is part of the Title V Policy and Guidance Database available at www2.epa.gov/title-v-operating-permits/title-v-operating-permit-policy-and-guidance-document-index. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Wind machines. [aerodynamics of sailwing vehicles

NASA Technical Reports Server (NTRS)

Lissaman, P. B. S.

1973-01-01

The basic elements of the air/water momentum exchange are described by the environment, the potential, the air and water subsystems, the total system, and the rule. Many of these topics have direct analogues in aerogenerator design. Aspects of optimal sail design and of waveless hulls are briefly outlined. A wind driven vehicle capable of moving directly downwind faster than the wind, is reported. The lecture is illustrated with slides and movie clips showing surfing catamarans, land and water versions of the Bauer vehicle, hang gliding, land sailing, and wind surfing.

Characterisation of plasma in a rail gun

NASA Technical Reports Server (NTRS)

Ray, P. K.

1986-01-01

The mechanism of plasma and projectile acceleration in a DC rail gun is described from a microscopic point of view through the establishment of the Hall field. The plasma conductivity is shown to be a tensor, indicating that there is a small component of current parallel to the direction of acceleration. The plasma characteristics are evaluated in the experiment of Bauer et. al., as a function of plasma mass through a simple fluid mechanical analysis of the plasma. By equating the energy dissipatated in the plasma with the radiation heat loss, the properties of the plasma are determined.

Evaluation of BAUER K220 High Pressure Breathing Air Compressor

DTIC Science & Technology

1990-03-01

switch , intermediate 6 Inter-cooler lstf2nd stage pressure lst/2nd stage 7 Inter-cooler 2nd/3rd stage 25 Pressure switch , intermediate 8 Inter-cooler...3rd/4th stage pressure 2nd/3rd stage 9 After-cooler 26 Pressure switch , intermediate 10 Inter-filter 2nd/3rd stage pressure 3rd/4th stage 11 Inter...filter 3rd/4th stage 27 Temperature switch 4th stage 12 Oil and water separator 28 Final pressure switch . 13 Safety valve 1st stage 29 3/2-way solenoid

Rollovers during play: Complementary perspectives.

PubMed

Smuts, Barbara; Bauer, Erika; Ward, Camille

2015-07-01

In this commentary, we compare and contrast Norman et al.s' findings on rollovers during dog play (Norman et al., 2015; the "target article") with our work on dog play fighting (Bauer and Smuts, 2007; Ward et al., 2008). We first review our major findings and then correct some errors in the target article's descriptions of our work. We then further explore the concept of "defensive" rollovers proposed in the target article. We conclude that a combination of the target article's approach and ours should inform future investigations of dog rollovers. Copyright © 2015 Elsevier B.V. All rights reserved.

Disk Susceptibility Studies with Cefazolin and Cephalothin

PubMed Central

Actor, Paul; Guarini, Joseph; Uri, Joseph; Dickson, Judith; Pauls, John F.; Weisbach, Jerry A.

1974-01-01

Cefazolin and cephalothin disk susceptibility and minimal inhibitory concentration determinations were conducted on 591 clinical isolates. Cefazolin demonstrated superior activity, as shown by lower minimal inhibitory concentrations, and a greater percentage of isolates inhibited in the disk susceptibility test. The cephalothin antibiotic class disk by the standard Bauer-Kirby method failed to detect susceptibility to cefazolin in a significant percentage of Escherchia coli, Enterobacter species, and Enterococcus isolates. A separate cefazolin disk with a susceptibility cut-off point of 18 mm is recommended. An alternative to a separate cefazolin disk would be a reinterpretation of the cephalothin susceptibility disk zone diameters so that it would more adequately predict cefazolin activity. PMID:4840450

Examination of bacteria drug resistance utilizing surface plasmon resonance

NASA Astrophysics Data System (ADS)

Chiang, Ya-Ling; Chen, How-Foo; Lin, Chi-Hung; Chen, Shean-Jen

2007-05-01

An antimicrobial testing method using surface plasmon resonance to improve the present techniques is reported in this paper. Different from conventional methods, namely Kirby-Bauer disk diffusion and variations of broth microdilution, the examination time is reduced from 18-24 hours or more to less than one hour after the treatment of antibiotics. E-coli resistant and susceptible to ampicillin are used in the test to demonstrate this innovative method. It is generally known that discovering a method to exam the bacterium resistance rapidly and correctly is very important for patients and for preventing infective disease from spreading. The method reported can benefit this requirement.

Valence-bond study of the /H2, D2/ exchange reaction mechanism.

NASA Technical Reports Server (NTRS)

Freihaut, B.; Raff, L. M.

1973-01-01

The exchange reaction of H2 with D2 to form 2 HD is important in that it is fundamentally the simplest four-body exchange reaction and should therefore represent a model system on which various theories of reactions dynamics might be tested. A number of theoretical and experimental investigations carried out on this system are reviewed. It is concluded that a Y yields T yields Y mechanism for the (H2, D2) exchange is not a low energy pathway that would make theory compatible with the shock-tube experiments of Bauer and Ossa (1966) and of Burcat and Lifshits (1967).

Foreword: Proceedings of the 15th International Winterschool on New Developments in Solid State Physics (Mauterndorf (Bad Hofgastein), 18 22 February 2008)

NASA Astrophysics Data System (ADS)

Jantsch, Wolfgang; Ferry, David; Kuchar, Friedl

2008-11-01

Günther Bauer Günther Bauer. This special issue of Journal of Physics: Condensed Matter is devoted to Günther Bauer, who celebrated his 65th birthday in September 2007. Günther has had a long career in condensed matter physics, but is known particularly for his studies of high magnetic field transport and optics in semiconductors and, more recently, for the discovery and x-ray analysis of self-organized 3D quantum dot crystals. However, his work is much broader than this, as indicated by the wide selection of topics which are represented in this special issue. Günther began his scientific career in Vienna, became associate Professor at the University of Ulm after habilitation at the Rheinisch-Westfälische Technische Hochschule Aachen, Germany, and then ascended to a full professorship at the Montanuniversität, Leoben, Austria, in 1980. He subsequently moved to the Johannes Kepler Universität, Linz, Austria, in 1990. Apart from his outstanding scientific achievements, Günther is also known for organizing the biannual winterschool on 'New Developments in Solid State Physics' beginning in 1980. Initially, he worked at this task together with Helmut Heinrich (until 2000) and Friedl Kuchar (1984 until now) and subsequently with Wolfgang Jantsch (who followed Helmut Heinrich in 2002). This winterschool was, and remains, very important in identifying new trends in solid state physics, and thus has a number of important proponents in the scientific community. It was at one of the first of these winterschools where the initial reports of the quantum Hall effect were presented, and it has been a meeting place where established experts (including three Nobel laureates) teach, and interact with students and young researchers. It is important to know that Günther's excellent international connections were necessary to maintain the high level of the winterschool over almost 30 years. After the first meeting in 1980 in Mariapfarr, these winterschools were held thirteen times in the castle of Mauterndorf, Province of Salzburg, Austria, and therefore the village name Mauterndorf became synonymous for this series within the semiconductor and nanoscience community. In 2008, the school had outgrown the available facilities in Mauterndorf, and relocated to Bad Hofgastein, not very far from Mauterndorf but providing a substantially larger venue, which allowed both facilities and accommodation for the ever growing number of attendees. In the last few winterschools, the main topic has been 'Semiconductor Nanostructures—Physics and Applications'. In 2008, we had about 240 participants from around the world and an outstanding scientific program comprising the most exciting developments of the past two years. Indeed, most papers in this special issue of Journal of Physics: Condensed Matter were presented at the 2008 Mauterndorf meeting. In addition, a number of outstanding experts on nanoscience and long term friends of the Mauterndorf winterschool volunteered to contribute to honour Günther. We thank all of them for their efforts.

Seasonal Changes in Estuarine Dissolved Organic Matter Due to Variations in Discharge, Flushing Times and Wind-driven Mixing Events

NASA Astrophysics Data System (ADS)

Dixon, Jennifer Louise

Estuaries are highly productive habitats that transport and transform organic matter (OM), experience large changes in ionic composition and act as a transition zone between terrestrial and marine environments (Paerl et al. 1998; Markager et al. 2011; Osburn et al. 2012). OM source and matrix effects (such as salinity and pH) influence the chemical structure of DOM in estuaries and therefore affect its bioavailability, photo-reactivity, and its overall fate in these systems (Jaffe et al. 2004; Boyd et al. 2010; Pace et al. 2012; Osburn et al. 2012; Cawley et al. 2013). Within estuaries, dissolved organic matter (DOM) is a heterogeneous mixture of aromatic and aliphatic compounds, and its composition in aquatic systems varies spatially and temporally with source (Bauer and Bianchi 2011). However, the main source of DOM in estuaries, rivers and other aquatic systems, originates from vascular plant detritus, soil humus, older fossil (i.e., petrogenic) organic carbon, black carbon, marine OM and in situ production (Hedges 2002; Houghton 2007; Bauer and Bianchi 2011). Chromophoric dissolved organic matter (CDOM), the light absorbing fraction of DOM, can be characterized using optical methods such as absorption and fluorescence spectroscopy (e.g. Coble, 1996; Stedmon and Markager, 2003). By analyzing the spatial and temporal variability of DOM and CDOM within estuaries, information pertaining to OM source and fate across the freshwater-marine continuum can be obtained. These methods offer an inexpensive, non-destructive means for obtaining sensitive measurements of a diverse group of organic compounds. By using this technology to analyze the spatial and temporal variability of CDOM within estuaries, information pertaining to OM source and fate across the freshwater-marine continuum can be obtained (Fellman et al. 2011; Osburn et al. 2012; Murphy et al. 2014). Chemical biomarkers are also routinely used to identify DOM sources in coastal waters. Examples are carbon stable isotopes (Bauer, 2002) and lignin (e.g., Benner and Opsahl, 2001; Harvey and Mannino, 2001). Marine DOM derived from phytoplankton typically has carbon stable isotope (delta13C) values that range from --20 to --22‰, while terrestrial DOM derived from C3 land plants typically have delta13C values that range from --26 to --28‰ (Bauer, 2002). Lignin is an important component of vascular plants, thus making it a unique geochemical biomarker, which can be used to trace the fate of terrestrial DOM in coastal seawater (e.g., Hernes and Benner, 2003; Walker et al. 2009; Osburn and Stedmon, 2011). Further, the ratios of the different phenolic compounds derived from the oxidation of lignin can be used to distinguish between plant sources (e.g. angiosperm vs. gymnosperm, or woody vs. non-woody tissue) and the extent of exposure to degradation (Hedges et al. 1988). The highly productive, eutrophic waters of the Neuse River Estuary (NRE), in eastern North Carolina, USA, serve as a transition zone for terrigenous DOM between the head of the Neuse River and Pamlico Sound. Previous studies have determined that the NRE is dominated by inputs from riverine discharge, yet very clear shifts in DOM quality are apparent as discharge varied (Paerl et al. 1998; Osburn et al. 2012). Furthermore, flushing times within the NRE will aid in determining whether DOM is primarily autochthonous or allochthonous and if it is processed internally or transported downstream to the Pamlico Sound (Paerl et al. 1998; Mari et al. 2007, Peierls et al. 2012). Therefore, the main sources of DOM and its composition can change throughout an estuary depending on the hydrodynamic conditions. For example, increases in flushing time may allow for the accumulation of autochthonous DOM because of (1) planktonic communities within the water column having more time to utilize nutrients within the system, resulting in phytoplankton blooms and (2) lower inputs of allochthonous OM from the NRE's watershed (Dixon et al. accepted). Therefore, the main sources of DOM and its composition can change throughout an estuary depending on the hydrodynamic conditions.

Solvent-free synthesis, spectral correlations and antimicrobial activities of some aryl E 2-propen-1-ones

NASA Astrophysics Data System (ADS)

Sathiyamoorthi, K.; Mala, V.; Sakthinathan, S. P.; Kamalakkannan, D.; Suresh, R.; Vanangamudi, G.; Thirunarayanan, G.

2013-08-01

Totally 38 aryl E 2-propen-1-ones including nine substituted styryl 4-iodophenyl ketones have been synthesised using solvent-free SiO2-H3PO4 catalyzed Aldol condensation between respective methyl ketones and substituted benzaldehydes under microwave irradiation. The yields of the ketones are more than 80%. The synthesised chalcones were characterized by their analytical, physical and spectroscopic data. The spectral frequencies of synthesised substituted styryl 4-iodophenyl ketones have been correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. The antimicrobial activities of 4-iodophenyl chalcones have been studied using Bauer-Kirby method.

Hexanuclear Fe(III) wheels functionalized by amino-acetonitrile derivatives

NASA Astrophysics Data System (ADS)

Kravtsov, Victor Ch.; Malaestean, Iurie; Stingach, Eugenia P.; Duca, Gheorghe G.; Macaev, Fliur Z.; van Leusen, Jan; Kögerler, Paul; Hauser, Jürg; Krämer, Karl; Decurtins, Silvio; Liu, Shi-Xia; Ghosh, Ashta C.; Garcia, Yann; Baca, Svetlana G.

2018-04-01

Three new hexanuclear Fe(III) coordination wheels [Fe6Cl6(L1)6]·5(MeCN) (1), [Na0.5Fe6Cl6(L1)6](N3)0.5·4.5(MeCN) (2), and [Fe6Cl6(L2)6]·2(MeCN) (3) have been synthesized with new prepared amino-acetonitrile derivatives 2-[bis(2-hydroxyethyl)amino]acetonitrile hydrochloride (H2L1) and 3-[bis(2-hydroxyethyl)amino]propanenitrile hydrochloride (H2L2). They were structurally characterized by single-crystal X-ray diffraction. Mößbauer spectroscopy and magnetic susceptibility measurements indicate dominant antiferromagnetic behavior between the Fe(III) centers.

VizieR Online Data Catalog: HD147379 b velocity curve (Reiners+, 2018)

NASA Astrophysics Data System (ADS)

Reiners, A.; Ribas, I.; Zechmeister, M.; Caballero, J. A.; Trifonov, T.; Dreizler, S.; Morales, J. C.; Tal-Or, L.; Lafarga, M.; Quirrenbach, A.; Amado, P. J.; Kaminski, A.; Jeffers, S. V.; Aceituno, J.; Bejar, V. J. S.; Guardia, J.; Guenther, E. W.; Hagen, H.-J.; Montes, D.; Passegger, V. M.; Seifert, W.; Schweitzer, A.; Cortes-Contreras, M.; Abril, M.; Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona, R.; Anglada-Escude, G.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Barrado, D.; Bauer, F. F.; Becerril, S.; Benitez, D.; Berdinas, Z. M.; Bergond, G.; Bluemcke, M.; Brinkmoeller, M.; Del Burgo, C.; Cano, J.; Cardenas Vazquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Czesla, S.; Diez-Alonso, E.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister, B.; Galadi-Enriquez, D.; Garcia-Piquer, A.; Garcia Vargas, M. L.; Gesa, L.; Gomez Galera, V.; Gonzalez Hernandez, J. I.; Gonzalez-Peinado, R.; Groezinger, U.; Grohnert, S.; Guijarro, A.; de Guindos, E.; Gutierrez-Soto, J.; Hatzes, A. P.; Hauschildt, P. H.; Hedrosa, R. P.; Helml!, Ing J.; H Enning, Th.; Hermelo, I.; Hernandez Arabi, R.; Hernandez Castano, L.; Hernandez Hernando, F.; Herrero, E.; Huber, A.; Huke, P.; Johnson, E. N.; de Juan, E.; Kim, M.; Klein, R.; Klueter, J.; Klutsch, A.; Kuerster, M.; Labarga, F.; Lamert, A.; Lampon, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; Launhardt, R.; Lopez Del Fresno, M.; Lopez-Gonzalez, M. J.; Lopez-Puertas, M.; Lopez Salas, J. F.; Lopez-Santiago, J.; Luque, R.; Magan Madinabeitia, H.; Mall, U.; Mancini, L.; Mandel, H.; Marfil, E.; Marin Molina, J. A.; Maroto Fernandez, D.; Martin, E. L.; Martin-Ruiz, S.; Marvin, C. J.; Mathar, R. J.; Mirabet, E.; Moreno-Raya, M. E.; Moya, A.; Mundt, R.; Nagel, E.; Naranjo, V.; Nortmann, L.; Nowak, G.; Ofir, A.; Oreiro, R.; Palle, E.; Panduro, J.; Pascual, J.; Pavlov, A.; Pedraz, S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger, M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhart, S.; Rhode, P.; Rix, H.-W.; Rodler, F.; Rodriguez, E.; Rodriguez-Lopez, C.; Rodriguez Trinidad, A.; Rohloff, R.-R.; Rosich, A.; ! Sadegi, S.; Sanchez-Blanco, E.; Sanchez Carrasco, M. A.; Sanchez-Lopez, A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schaefer, S.; Schmitt, J. H. M. M.; Schiller, J.; Schoefer, P.; Solano, E.; Stahl, O.; Strachan, J. B. P.; Stuermer, J.; Suarez, J. C.; Tabernero, H. M.; Tala, M.; Tulloch, S. M.; Ulbrich, R.-G.; Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.

2017-11-01

We analyzed data from the CARMENES VIS channel and HIRES/Keck. The CARMENES measurements were taken in the context of the CARMENES search for exoplanets around M dwarfs. The CARMENES instrument consists of two channels: the VIS channel obtains spectra at a resolution of R=94600 in the wavelength range 520-960nm, while the NIR channel yields spectra of R=80400 covering 960-1710nm. Both channels are calibrated in wavelength with hollow-cathode lamps and use temperature- and pressure-stabilized Fabry-Perot etalons to interpolate the wavelength solution and simultaneously monitor the spectrograph drift during nightly operations (Bauer et al., 2015A&A...581A.117B). (1 data file).

Powerful Nearby Supernova Caught By Web

NASA Astrophysics Data System (ADS)

2008-09-01

One of the nearest supernovas in the last 25 years has been identified over a decade after it exploded. This result was made possible by combining data from the vast online archives from many of the world's premier telescopes. The supernova was first singled out in 2001 by Franz Bauer, then at Penn State and now at Columbia University, who noticed a bright, variable object in the spiral galaxy Circinus using NASA's Chandra X-ray Observatory. Though the source displayed some exceptional properties, at the time Bauer and his Penn State colleagues could not confidently identify its nature. It was not until years later that Bauer and his team were able to confirm this object was a supernova. Clues in a spectrum from the European Southern Observatory's Very Large Telescope (VLT) led the team to search through data from 18 different telescopes, both in space and on the ground, nearly all of which was from archives. Because this object was found in a nearby galaxy, making it relatively easy to study, the public archives of these telescopes contained abundant data on this galaxy. The data show that this supernova, dubbed SN 1996cr, is among the brightest supernovas ever seen in radio and X-rays. It also bears many striking similarities to the famous supernova SN 1987A, which occurred in a galaxy only 160,000 light years from Earth. "This supernova appears to be a wild cousin of SN 1987A," said Bauer. "These two look alike in many ways, except this newer supernova is intrinsically a thousand times brighter in radio and X-rays." Optical images from the archives of the Anglo-Australian Telescope in Australia show that SN 1996cr exploded between February 28, 1995 and March 15, 1996, nearly a decade after SN 1987A. SN 1996cr may not have been noticed by astronomers at the time because it was only visible in the southern hemisphere, which is not as widely monitored as the northern. Among the five nearest supernovas of the last 25 years, it is the only one that was not seen shortly after the explosion. X-rayChandra X-ray Image SN 1996cr was not detected by other major X-ray observatories in orbit - ROSAT and ASCA - around the time of explosion. Rather, it wasn't until several years later that it was detected as an X-ray source by Chandra (launched in 1999), and has become steadily brighter ever since. Previously, SN 1987A had been the only known supernova with an X-ray output observed to increase over time. "Supernovas that are close enough to be studied in detail like this are quite rare and may only appear once a decade, so we don't want to miss such an important opportunity for discovery," said Bauer. "It's a bit of a coup to find SN 1996cr like we did, and we could never have nailed it without the serendipitous data taken by all of these telescopes. We've truly entered a new era of `Internet astronomy'." People Who Read This Also Read... Chandra Data Reveal Rapidly Whirling Black Holes Dark Energy Found Stifling Growth in Universe Ghostly Glow Reveals a Hidden Class of Long-Wavelength Radio Emitters Jet Power and Black Hole Assortment Revealed in New Chandra Image The data, combined with theoretical work, has led the team to the following model. Before it exploded, the parent star cleared out a large cavity around it, either via a fast wind or an outburst from the star late in its life. Then, the blast wave from the explosion expanded relatively unimpeded into this cavity. Once the blast wave hit the dense material surrounding SN1996cr, the impact caused the system to glow brightly in X-ray and radio emission. The X-ray and radio emission from SN 1987A is fainter because the surrounding material is probably less compact. Astronomers think that both SN 1987A and SN 1996cr show evidence for these pre-explosion clear-outs by the star doomed to explode. Having two nearby examples suggests that this type of activity could be relatively common during the death of massive stars. "Not only does our work suggest that SN 1987A isn't as unusual as previously thought, but it also teaches us more about the tremendous upheavals that massive stars can undergo during their lifetime," said co-author Vikram Dwarkadas of the University of Chicago. SN 1996cr, at a distance of about 12 million light years, will be a compelling target for future work because it is nearby and so much brighter than a typical supernova. These results will appear in an upcoming issue of The Astrophysical Journal. Other co-authors on this paper include Niel Brandt (Penn State), Stefan Immler (NASA Goddard Space Flight Center), Norbert Bartel (York University, Canada), and Michael Bietenholz (York University and Hartebeesthoek Radio Observatory, South Africa). NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.

Reconstructing the Thermo-tectonic history of the Rwenzori Mountains, D. R. Congo

NASA Astrophysics Data System (ADS)

Mansour, S.; Bauer, F.; Glasmacher, P. D. U. A. A.; Grobe, R. W.; Starz, M.

2014-12-01

The Albertine Rift forms the northern section of the western Rift of the East African Rift System (EARS). The Rwenzori Mtns evolved along the eastern rift shoulder of the Albertine Rift, rising up to form a striking feature within the rift valley with elevations reaching 5109 m a.s.l. While, the scarcity of volcanic activity in the Western Rift has raised questions about the Rwenzori Mtns origin and how this fits into the general evolution of the Albertine Rift and the EARS. Detailed thermochronologic study of Bauer et al., (2013) on the eastern side on Rwenzori Mtns, differentiated it into northern and southern blocks. The northern block cooled faster to ~120 °C in Carboniferous to Permian times. The second cooling event to ~70 °C occurred in Mesozoic time. The third cooling event to surface temperature occurred in the Neogene. While, the southern block shows an earlier onset of cooling at >400 Ma. Temperatures of about 70 °C were reached in Silurian to Devonian times. During this study, 33 samples were collected from the western side of central Rwenzori. Zircon and apatite fission track and (U/Th)-He techniques were applied on these samples. The apatite fission track data could be divided into three age groups; ~45±11, ~25±5, ~12±2 Ma. These results reveal the difference in thermo-tectonic history between the eastern and western flanks of Rwenzori Mtns and support the tilt uplift geometry hypotheses (e.g. Pickford et al., 1993). ReferencesBauer, F.U., Glasmacher, U.A., Ring, U., Karl, M., Schumann, A., Nagudi, B., 2013. Tracing the exhumation history of the Rwenzori Mountains, Albertine Rift, Uganda, using low-temperature thermochronology, Tectonophysics, 599, 8-28. http://dx.doi.org/10.1016/j.tecto.2013.03.032. Pickford, M., Senut, B., Hadoto, D., 1993. Geology and Palaeobiology of the Albertine Rift Valley Uganda-Zaire, vol. 1. Geology. CIFEG Occas, Orleans. Publication, vol. 24, pp. 1-190.

Thermo-tectonic history reconstruction of the Rwenzori Mountains, D. R. Congo

NASA Astrophysics Data System (ADS)

Mansour, Sherif; Bauer, Friederike; Glasmacher, Ulrich; Grobe, René; Starz, Matthias

2015-04-01

The Albertine Rift forms the northern section of the western Rift of the East African Rift System (EARS) which was developed during the Neogene time. The Rwenzori Mtns evolved along the eastern rift shoulder of the Albertine Rift, rising up to form a striking feature within the rift valley. The scarcity of volcanic activity in the Western Rift has raised questions about the Rwenzori Mtns origin and evolution and how this fits into the general evolution of the Albertine Rift and the EARS. The Rwenzori Mtns represent the horst block in the Albertine Rift, with elevations reaching 5109 m a.s.l. (Margherita Peak). The main lithologies of the Rwenzori Mtns are gneiss, schist and amphibolite, subordinate intrusive rocks with various metamorphic overprint, and quartzite of Precambrian age (Tanner, 1971). All these units are intensively truncated by N-S, NW-SE, NE-SW and E-W trending normal faults, locally with a significant strike-slip component (Ring, 2008). The slope Rwenzori Mtns western flank is much steeper than the eastern one. This asymmetry is most striking in the central part where the western flank rises from about 1000 m a.s.l. to more than 5000 m a.s.l. in less than 15 km while, the eastern flank plunges to 1000 m a.s.l. again along a distance of more than 30 km (Bauer et al., 2013). Detailed thermochronologic study on the eastern (Uganda) side of central Rwenzori differentiated it into northern and southern blocks (Bauer et al., 2013). Samples from the northern block cooled faster, with three cooling/exhumation events; to ~120 °C in Carboniferous to Permian times, to ~70 °C in Mesozoic times, and to surface temperature in the Neogene. While, the southern block shows an earlier onset of cooling/exhumation events (>400 Ma). On the other hand, 33 samples from the western (Congo) side of central Rwenzori were studied using fission track and (U/Th)-He techniques. The apatite fission track data gives much younger cooling ages. Which, distinguished in three cooling age groups with; Eocene, Oligo-Miocene, and Middle Miocene ages. These results reveal the difference in thermo-tectonic history between the eastern and western flanks of Rwenzori Mtns and support the tilt uplift geometry hypotheses (e.g. Pickford et al., 1993). References Bauer, F.U., Glasmacher, U.A., Ring, U., Karl, M., Schumann, A., Nagudi, B. (2013). Tracing the exhumation history of the Rwenzori Mountains, Albertine Rift, Uganda, using low-temperature thermochronology, Tectonophysics, 599, 8-28. http://dx.doi.org/10.1016/j.tecto.2013.03.032. Pickford, M., Senut, B., Hadoto, D., 1993. Geology and Palaeobiology of the Albertine Rift Valley Uganda-Zaire, vol. 1. Geology. CIFEG Occas, Orleans. Publication, vol. 24, pp. 1-190. Ring, U., 2008. Extreme uplift of the Rwenzori Mountains in the East African Rift, Uganda: structural framework and possible role of glaciations. Tectonics 27 (TC4018). http://dx.doi.org/10.1029/2007TC002176. Tanner, P.W.G., 1971. The Stanley Volcanics formation of Ruwenzori, Uganda. Fifteenth Annual Report of the Research Institute of African Geology. University of Leeds.

Proposed quality control guidelines for antimicrobial susceptibility tests using tilmicosin.

PubMed Central

Shryock, T R; White, D W; Werner, C S; Staples, J M

1995-01-01

Quality control guidelines for tilmicosin, a novel veterinary-use-only macrolide, were developed in a multi-laboratory study according to established National Committee for Clinical Laboratory Standards (NCCLS) procedures (M23-T2). Tilmicosin was incorporated into Sensititre plates for broth microdilution endpoint testing and into two lots of 15-micrograms disks for Kirby-Bauer agar disk diffusion testing. One common lot and five unique lots of Mueller-Hinton media were used. (Broth was cation adjusted, and agar was supplemented with 5% defibrinated sheep blood.) Bacteria used for reference strains included Pasteurella haemolytica 128K, Pasteurella multocida ATCC 43137, and Staphylococcus aureus ATCC 29213 (microdilution) and ATCC 25923 (disk). Replicate tests were conducted. Disk diffusion and broth microdilution quality control ranges are proposed. PMID:7714188

It pays to be Herr Kaiser: Germans with noble-sounding surnames more often work as managers than as employees.

PubMed

Silberzahn, Raphael; Uhlmann, Eric Luis

2013-12-01

In the field study reported here (N = 222,924), we found that Germans with noble-sounding surnames, such as Kaiser ("emperor"), König ("king"), and Fürst ("prince"), more frequently hold managerial positions than Germans with last names that either refer to common everyday occupations, such as Koch ("cook"), Bauer ("farmer"), and Becker/Bäcker ("baker"), or do not refer to any social role. This phenomenon occurs despite the fact that noble-sounding surnames never indicated that the person actually held a noble title. Because of basic properties of associative cognition, the status linked to a name may spill over to its bearer and influence his or her occupational outcomes.

Antimicrobial activity of honey of africanized bee (Apis mellifera) and stingless bee, tiuba (Melipona fasciculata) against strains of Escherichia coli, Pseudomona aeruginosa and Staphylococcus aureus

NASA Astrophysics Data System (ADS)

Tenório, Eleuza Gomes; Alves, Natália Furtado; Mendes, Bianca Evanita Pimenta

2017-11-01

The objective of this study was to investigate the antimicrobial activity of honey of Africanized bees (Apis mellifera) and stingless bees (Melipona fasciculata), produced under the same flowering conditions, in municipalities of Baixada Maranhese, Brazil, against strains of pathogenic bacteria, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In each municipality, the apiary and meliponario were less than 150 meters away from each other. The Kirby-Bauer method, and the diffusion technique of the agar plate through the extension of the inhibition in millimeters were used. The test results were negative for all samples, which did not demonstrate antimicrobial activity in any of the microorganisms tested.

Data on fossil fuel availability for Shared Socioeconomic Pathways.

PubMed

Bauer, Nico; Hilaire, Jérôme; Brecha, Robert J; Edmonds, Jae; Jiang, Kejun; Kriegler, Elmar; Rogner, Hans-Holger; Sferra, Fabio

2017-02-01

The data files contain the assumptions and results for the construction of cumulative availability curves for coal, oil and gas for the five Shared Socioeconomic Pathways. The files include the maximum availability (also known as cumulative extraction cost curves) and the assumptions that are applied to construct the SSPs. The data is differentiated into twenty regions. The resulting cumulative availability curves are plotted and the aggregate data as well as cumulative availability curves are compared across SSPs. The methodology, the data sources and the assumptions are documented in a related article (N. Bauer, J. Hilaire, R.J. Brecha, J. Edmonds, K. Jiang, E. Kriegler, H.-H. Rogner, F. Sferra, 2016) [1] under DOI: http://dx.doi.org/10.1016/j.energy.2016.05.088.

Influence of CuO nanoparticle on palm oil based alkyd resin preparation and its antimicrobial activity

NASA Astrophysics Data System (ADS)

Ruey Ong, Huei; Maksudur Rahman Khan, Md.; Ramli, Ridzuan; Shein Hong, Chi; Yunus, Rosli Mohd

2018-03-01

An alkyd resin has been synthesized from palm oil that reacted with glycerol and phthalic anhydride by alcoholysis-polyesterification process and co-catalyzed by CuO nanoparticle. The CuO nanoparticle was pre-prepared in the glycerol via sol gel method, which creates a new reaction condition for resin preparation. The resins were characterized by fourier transform infrared spectroscopy (FTIR), where a new ester linkage bond (C-O-C) was noticed for resin sample. The antimicrobial activity and the curing behaviour of the resin were determined by Kirby-Bauer and differential scanning calorimeter technique. It was found that, the addition of CuO speeded up the reaction rate and played antimicrobial role. Moreover, it shortens the reaction time of alcoholysis and polyesterification process.

The Influence of Solvent on the Structural Properties of trans-(NHC)PtI2Py Complex: A Platinum-Based Anticancer Drug

NASA Astrophysics Data System (ADS)

Sadigh Vishkaee, Teherh; Fazaeli, Reza

2018-06-01

Quantum chemical calculations using MPW1PW91 method were applied to analyze the solvent effect on the structural, spectral, and thermochemical parameters for a platinum-based anticancer drug trans-(NHC)PtI2Py complex. The solvent effects were examined by the self-consistent reaction field theory (SCRF) based on Polarizable Continuum Model (PCM). The linear correlations between the solvation energies, HOMO-LUMO gaps, IR-active stretching vibration of Pt-N bonds and N-H of NHC ligand with dielectric constants of solvents were studied. The wave numbers of these IR-active stretching vibrations in different solvents were correlated with the Kirkwood-Bauer-Magat equation (KBM). The thermodynamic activation parameter such free energy of solvation, enthalpy of solvation were also calculated.

[Antibiotic resistance pattern of 24, 526 strains of Vibrio cholerae O1 isolated in Mexico from 1991 to 1993].

PubMed

Giono-Cerezo, S; Zárate, A; Gutiérrez, L; Valdespino, J L

1994-01-01

Profile of antimicrobial resistance by Kirby-Bauer method was performed on 24526 Vibrio cholerae O1 strains isolated in México (1991-1993) from fecal swabs in cholera cases and from asymptomatic carriers. Minimal inhibitory concentration (MIC) tests for tetracycline (Te) and doxycycline (D) were done on selected strains. Single antibiotic discs were used at concentrations of: Te, 30 micrograms; D, 30 micrograms; erythromycin (E), 15 micrograms; chloramphenicol (CM), 30 micrograms; ampicillin (AM), 10 micrograms; trimethoprim-sulfamethoxazole (SXT) 1.25 micrograms/23.75 micrograms. Strains whose halos were of a smaller diameter than the intermediate value were considered resistant. It is important to maintain surveillance on antimicrobial susceptibility as epidemiological marker on geographical selected areas in order to detect changes of resistant patterns.

Antimicrobial activity of honey of stingless bees, tiúba (Melipona fasciculata) and jandaira (Melipona subnitida) compared to the strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa

NASA Astrophysics Data System (ADS)

Tenório, Eleuza Gomes; de Jesus, Natália Rocha; Nascimento, Adenilde Ribeiro; Teles, Amanda Mara

2015-12-01

This study aimed to investigate the antimicrobial activity of honeys of stingless bees produced in Maranhão, tiúba (Melipona fasciculata) and jandaira (Melipona subnitida), opposite the strains of pathogenic bacteria, namely, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The honey samples were collected from different regions of Maranhão. Of the 17 samples collected, twelve samples were honey M. fasciculata and five were honey M. subnitida. We used the Kirby-Bauer method, and the technique of agar disk diffusion through the extent of inhibition in milimetros. Results were negative for all samples from M. fasciculata. However, the tests for M. subnitida demonstrated bacteriostatic halos ranging from 12 to 32,6mm.

Diaquachloro-tris(ethyl-p-Aminobenzoate)copper(II) Chloride: Synthesis, Characterization and In Vitro Investigation of Antibacterial Activity

NASA Astrophysics Data System (ADS)

Rahardjo, S. B.; Lestari, W. W.; Syaima, H.

2017-07-01

The new complex of [Cu(benz)3(H2O)2Cl]Cl has been synthesized in 1:4 mole ratio of CuCl2·2H2O and ethyl-p-aminobenzoate (benz) in ethanol at room temperature. The complex was characterized by UV-Vis and infrared spectroscopy, Atomic Absorption Spectroscopy (AAS), thermal analysis, magnetic measurement and molar conductivity. Infrared spectra indicated that benz was coordinated to the metal ion through nitrogen of primary amine group. Water molecules and chloride ion were also coordinated to Cu(II). CuCl2·2H2O, benz, and Cu(II) complex were screened for investigating in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli using a modified Kirby-Bauer method.

P24 Plasma Physics Summer School 2012 Los Alamos National Laboratory Summer lecture series for students

DOE Office of Scientific and Technical Information (OSTI.GOV)

Intrator, Thomas P.; Bauer, Bruno; Fernandez, Juan C.

2012-09-07

This report covers the 2012 LANL summer lecture series for students. The lectures were: (1) Tom Intrator, P24 LANL: Kick off, Introduction - What is a plasma; (2) Bruno Bauer, Univ. Nevada-Reno: Derivation of plasma fluid equations; (3) Juan Fernandez, P24 LANL Overview of research being done in p-24; (4) Tom Intrator, P24 LANL: Intro to dynamo, reconnection, shocks; (5) Bill Daughton X-CP6 LANL: Intro to computational particle in cell methods; (6) Kirk Flippo, P24 LANL: High energy density plasmas; (7) Thom Weber, P24 LANL: Energy crisis, fission, fusion, non carbon fuel cycles; (8) Tom Awe, Sandia National Laboratory: Magnetomore » Inertial Fusion; and (9) Yongho Kim, P24 LANL: Industrial technologies.« less

Potent Inhibition of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome in Bats, by Cold-Pressed, Terpeneless, Valencia Orange Oil.

PubMed

Boire, Nicholas; Zhang, Sean; Khuvis, Joshua; Lee, Rick; Rivers, Jennifer; Crandall, Philip; Keel, M Kevin; Parrish, Nicole

2016-01-01

The causative agent of White-nose Syndrome (WNS), Pseudogymnoascus destructans, has been shown to be fatal to several species of bats in North America. To date, no compounds or chemical control measures have been developed which eliminates the growth of the fungus in the environment or in affected animals. In the current study, we evaluated the activity of cold-pressed, terpeneless orange oil (CPT) against multiple isolates of P. destructans in vitro. For all assays, a modified Kirby-Bauer disk diffusion assay was used. Standardized spore suspensions were prepared, adjusted to a specific optical density, and used to plate fungal lawns. Plates were incubated at either 15°C or 4°C for up to 6 months and checked at regular intervals for growth. Once controls had grown, zones of inhibition were measured (mm) on test plates and compared to those obtained using current antifungal drugs. All P. destructans isolates were completely inhibited by 100% CPT (10 μL) at 1 month of incubation regardless of temperature (4°C and 15°C). Complete inhibition persisted up to 6 months following a single exposure at this concentration. Of the standard antifungals, only amphotericin B demonstrated any activity, resulting in zone diameters ranging from 58 mm to 74 mm. CPT, at the highest concentration tested (100%), had no significant effect against a variety of other environmental organisms including various filamentous fungi, bacteria and aerobic actinomycetes. Given that CPT is relatively non-toxic, the possibility exists that the all-natural, mixture could be used as an environmental pre-treatment to eradicate P. destructans from bat habitats. Additional studies are needed to assess any undesirable effects of CPT on bat behavior and health and overall impacts on other members of the interconnected ecosystem(s).

Potent Inhibition of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome in Bats, by Cold-Pressed, Terpeneless, Valencia Orange Oil

PubMed Central

Boire, Nicholas; Zhang, Sean; Khuvis, Joshua; Lee, Rick; Rivers, Jennifer; Crandall, Philip; Keel, M. Kevin; Parrish, Nicole

2016-01-01

The causative agent of White-nose Syndrome (WNS), Pseudogymnoascus destructans, has been shown to be fatal to several species of bats in North America. To date, no compounds or chemical control measures have been developed which eliminates the growth of the fungus in the environment or in affected animals. In the current study, we evaluated the activity of cold-pressed, terpeneless orange oil (CPT) against multiple isolates of P. destructans in vitro. For all assays, a modified Kirby-Bauer disk diffusion assay was used. Standardized spore suspensions were prepared, adjusted to a specific optical density, and used to plate fungal lawns. Plates were incubated at either 15°C or 4°C for up to 6 months and checked at regular intervals for growth. Once controls had grown, zones of inhibition were measured (mm) on test plates and compared to those obtained using current antifungal drugs. All P. destructans isolates were completely inhibited by 100% CPT (10 μL) at 1 month of incubation regardless of temperature (4°C and 15°C). Complete inhibition persisted up to 6 months following a single exposure at this concentration. Of the standard antifungals, only amphotericin B demonstrated any activity, resulting in zone diameters ranging from 58 mm to 74 mm. CPT, at the highest concentration tested (100%), had no significant effect against a variety of other environmental organisms including various filamentous fungi, bacteria and aerobic actinomycetes. Given that CPT is relatively non-toxic, the possibility exists that the all-natural, mixture could be used as an environmental pre-treatment to eradicate P. destructans from bat habitats. Additional studies are needed to assess any undesirable effects of CPT on bat behavior and health and overall impacts on other members of the interconnected ecosystem(s). PMID:26849057

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

NASA Image and Video Library

2004-01-05

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

NASA Image and Video Library

2004-01-05

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASA’s ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASA’s Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASA’s Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

Antimicrobial and antitumor activity of platinum and palladium complexes of novel spherical aramides nanoparticles containing flexibilizing linkages: structure-property relationship.

PubMed

Elhusseiny, Amel F; Hassan, Hammed H A M

2013-02-15

Square planar Pd (II) and octahedral Pt (IV) complexes with novel spherical aramides nanoparticles containing flexible linkages ligands have been synthesized and characterized using analytical and spectral techniques. The synthesized complexes have been tested for their antimicrobial activity using Kirby-Bauer disc diffusion method. The antitumor activity has been performed using liver carcinoma (HEPG2), breast carcinoma (MCF7) and colon carcinoma (HCT 116) cell lines. Palladium complexes of polyamides containing sulfones showed the highest potency as antibacterial and antifungal agents. Platinum complexes containing sulfone and ether flexible linkages and chloro groups exhibited high potency as antitumor and antimicrobial agents. The uniform sizes of these nanomaterials could find biological uses such as immune assay and other medical purposes. Copyright © 2012 Elsevier B.V. All rights reserved.

Ring-polymer instanton theory of electron transfer in the nonadiabatic limit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richardson, Jeremy O., E-mail: jeremy.richardson@fau.de

We take the golden-rule instanton method derived in the previous paper [J. O. Richardson, R. Bauer, and M. Thoss, J. Chem. Phys. 143, 134115 (2015)] and reformulate it using a ring-polymer instanton approach. This gives equations which can be used to compute the rates of electron-transfer reactions in the nonadiabatic (golden-rule) limit numerically within a semiclassical approximation. The multidimensional ring-polymer instanton trajectories are obtained efficiently by minimization of the action. In this form, comparison with Wolynes’ quantum instanton method [P. G. Wolynes, J. Chem. Phys. 87, 6559 (1987)] is possible and we show that our semiclassical approach is the steepest-descentmore » limit of this method. We discuss advantages and disadvantages of both methods and give examples of where the new approach is more accurate.« less

Chemical-potential flow equations for graphene with Coulomb interactions

NASA Astrophysics Data System (ADS)

Fräßdorf, Christian; Mosig, Johannes E. M.

2018-06-01

We calculate the chemical potential dependence of the renormalized Fermi velocity and static dielectric function for Dirac quasiparticles in graphene nonperturbatively at finite temperature. By reinterpreting the chemical potential as a flow parameter in the spirit of the functional renormalization group (fRG) we obtain a set of flow equations, which describe the change of these functions upon varying the chemical potential. In contrast to the fRG the initial condition of the flow is nontrivial and has to be calculated separately. Our results are consistent with a charge carrier-independent Fermi velocity v (k ) for small densities n ≲k2/π , supporting the comparison of the zero-density fRG calculation of Bauer et al. [Phys. Rev. B 92, 121409 (2015), 10.1103/PhysRevB.92.121409], with the experiment of Elias et al. [Nat. Phys. 7, 701 (2011), 10.1038/nphys2049].

DOE Office of Scientific and Technical Information (OSTI.GOV)

McNamara, B.

Tandem and stellarator equilibria at high ..beta.. have proved hard to compute and the relaxation methods of Bauer et al., Chodura and Schluter, Hirshman, Strauss, and Pearlstein et al. have been slow to converge. This paper reports an extension of the low-..beta.. analytic method of Pearlstein, Kaiser, and Newcomb to arbitrary ..beta.. for tandem mirrors which converges in 10 to 20 iterations. Extensions of the method to stellarator equilibria are proposed and are very close to the analytic method of Johnson and Greene - the stellarator expansion. Most of the results of all these calculations can be adequately described bymore » low-..beta.. approximations since the MHD stability limits occur at low ..beta... The tandem mirror, having weak curvature and a long central cell, allows finite Larmor radius effects to eliminate most ballooning modes and offers the possibility of really high average ..beta... This is the interest in developing such three-dimensional numerical algorithms.« less

High Magnetic Field Properties of Ce2Rh3Ge5

NASA Astrophysics Data System (ADS)

Wartenbe, Mark

2015-03-01

The competition between localized and delocalized f electrons in heavy fermion materials produces a wide variety of interesting physical phenomena. Among these compounds is Ce2Rh3Ge5. This heavy-fermion system undergoes an antiferromagnetic transition below 4K and exhibits an angle dependent magnetic phase transition around 25 tesla. In addition, RF conductivity measurements in pulsed field (65T) have revealed quantum oscillations. Temperature dependence at fixed angle indicates relatively heavy effective masses of values ranging from around 3me on up to 10me. This indicates that the narrow f-electron density of states is partially hybridized close to the Fermi energy, but also places strict cryogenic constraints upon the measurement (3Helium temperatures are required). Fermi surface calculations have produced complex figures which lend validation to such rich behavior. Ryan Baumbach, Andrew Gallagher, Eric Bauer, Ross McDonald, Kuan-Wen Chen,David Graf.

Evaluation of anti-plaque microbial activity of Azadirachta indica (neem oil) in vitro: A pilot study.

PubMed

Elavarasu, Sugumari; Abinaya, P; Elanchezhiyan, S; Thangakumaran; Vennila, K; Naziya, K B

2012-08-01

Probably microbial plaque is the main etiology for periodontal tissue inflammation. Various chemical agents have been evaluated over the years with respect to their antimicrobial effects in the oral cavity. However, all are associated with side effects that prohibit regular long-term use. Therefore, the effectiveness of Azadirachta indica (neem) against plaque formation is considered to be vital, with lesser side effects. The aim of the present study is to evaluate and prove the antimicrobial activity of neem using plaque samples. Culture was prepared using brain heart infusion broth reagent. Dental plaque samples were used for that. Kirby-Bauer antimicrobial susceptibility test procedure was carried away with the sample. Neem oil was kept in the agar plate with culture and the diameter of inhibition zones was calculated. Results showed inhibition zones on the agar plate around neem oil. Study shows definite antiplaque activity of neem oil.

Remotely Searching for Noctiluca Miliaris in the Arabian Sea

NASA Technical Reports Server (NTRS)

Werdell, P. Jeremy; Roesler, Collin S.; Goes, Joaquim I.

2014-01-01

Reversing monsoonal winds in the Arabian Sea result in two seasons with elevated biological activity, namely the annual summer Southwest Monsoon (SWM; June to September) and winter Northeast Monsoon (NEM; November to March) [Wiggert et al., 2005]. Generally speaking, the SWM and NEM create two geographically distinct blooms [Banse and English, 2000; Levy et al., 2007]. In the summer, winds from the southwest drive offshore Ekman transport and coastal upwelling along the northwestern coast of Africa, which brings nutrient-rich water to the surface from below the permanent thermocline [Bauer et al., 1991]. In the winter, cooling of the northern Arabian Sea causes surface waters to sink, which generates convective mixing that injects nutrients throughout the upper mixed layer [Madhupratap et al., 1996]. This fertilization of otherwise nutrient-deplete surface waters produces one of the most substantial seasonal extremes of phytoplankton biomass and carbon flux anywhere in the world [Smith, 2005].

Antimicrobial-resistant Klebsiella species isolated from free-range chicken samples in an informal settlement.

PubMed

Fielding, Burtram C; Mnabisa, Amanda; Gouws, Pieter A; Morris, Thureyah

2012-02-29

Sub-therapeutic doses of antimicrobial agents are administered routinely to poultry to aid growth and to prevent disease, with prolonged exposure often resulting in bacterial resistance. Crossover of antibiotic resistant bacteria from poultry to humans poses a risk to human health. In this study, 17 chicken samples collected from a vendor operating in an informal settlement in the Cape Town Metropolitan area, South Africa were screened for antimicrobial-resistant Gram-negative bacilli using the Kirby Bauer disk diffusion assay. IN TOTAL, SIX ANTIBIOTICS WERE SCREENED: ampicillin, ciprofloxacin, gentamicin, nalidixic acid, tetracycline and trimethoprim. Surprisingly, Klebsiella ozaenae was identified in 96 and K. rhinoscleromatis in 6 (n=102) of the samples tested. Interestingly, ∼40% of the isolated Klebsiella spp. showed multiple resistance to at least three of the six antibiotics tested. Klebsiella ozaenae and K. rhinoscleromatis cause clinical chronic rhinitis and are almost exclusively associated with people living in areas of poor hygiene.

[Report of Quambalaria cyanescens associated with birch].

PubMed

Antropova, A B; Bilanenko, E N; Mokeeva, V L; Chekunova, L N; Kachalkin, A V; Shtaer, O V; Kamzolkina, O V

2014-01-01

Long-term microbiological investigation of the pollen of silver birch (Betula pendula) in the Mos- cow, and Moscow region areas revealed that: almost one-third of the analyzed samples, contained the fungus identified by morphological, cultural, and molecular genetic techniques as Quambalaria cyanescens (de Hoog & G. A. de Vries) Z.W. de Beer, Begerow & R. Bauer. This species was previously known mostly as a syrmbiont of tropical plants of the generaEucalyptus and Cortyminbia and has not been isolated in Russia. We revealed a close association between Quambalaria cyanescens and silver birch. The micromycete was regulaly detected in pollen samples, as well as on the.inside and outside of the aments, on the surface of leaves and branches. It was never isolated from other plant species in the investigated area. The data on the morphological and cultural characteristics of the fungus, its cell ultrastructure, and occurrence are presented, as well as the phylogenetic analysis of the isolated strains.

Effect of the science teaching advancement through modeling physical science professional development workshop on teachers' attitudes, beliefs and content knowledge and students' content knowledge

NASA Astrophysics Data System (ADS)

Dietz, Laura

The Science Teaching Advancement through Modeling Physical Science (STAMPS) professional development workshop was evaluated for effectiveness in improving teachers' and students' content knowledge. Previous research has shown modeling to be an effective method of instruction for improving student and teacher content knowledge, evidenced by assessment scores. Data includes teacher scores on the Force Concept Inventory (FCI; Hestenes, Wells, & Swackhamer, 1992) and the Chemistry Concept Inventory (CCI; Jenkins, Birk, Bauer, Krause, & Pavelich, 2004), as well as student scores on a physics and chemistry assessment. Quantitative data is supported by teacher responses to a post workshop survey and classroom observations. Evaluation of the data shows that the STAMPS professional development workshop was successful in improving both student and teacher content knowledge. Conclusions and suggestions for future study are also included.

Evidence for a photoprotective function for secondary carotenoids of snow algae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bidigare, R.R.; Ondrusek, M.E.; Kennicutt, M.C. II

Snow algae occupy a unique habitat in high altitude and polar environments. These algae are often subject to extremes in nutrient availability, acidity, solar irradiance, desiccation, and ambient temperature. This report documents the accumulation of secondary carotenoids by snow algae in response to the availability of nitrogenous nutrients. Unusually large accumulations of astaxanthin esters in extra-chloroplastic lipid globules produce the characteristic red pigmentation typical of some snow algae (e.g., Chlamydomonas nivalis (Bauer) Wille). Consequently, these compounds greatly reduce the amount of light available for absorption by the light-harvesting pigment-protein complexes, thus potentially limiting photoinhibition and photodamage caused by intense solarmore » radiation. The esterification of astaxanthin with fatty acids represents a possible mechanism by which this chromophore can be concentrated within cytoplasmic globules to maximize its photoprotective efficiency. 53 refs., 2 figs., 4 tabs.« less

Preliminary phytochemical screening and antimicrobial evaluation of three medicinal plants used in Nigeria.

PubMed

Baba, Haruna; Onanuga, Adebola

2011-01-01

Methanol extract of three Nigerian medicinal plants were screened for antimicrobial activity using modified Kirby-Bauer disc diffusion and agar dilution techniques to determine the diameters of zone of inhibition and minimum inhibitory concentrations (MIC) of the extracts respectively. The extract of each of the plants were tested against five clinical bacterial isolates comprising of two Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumonia) organisms. All the extracts exhibited moderate to high level of antimicrobial activities against these microorganisms. Phytochemical screening of powdered plant material revealed the presence of some secondary metabolites such as alkaloids, saponins, tannins, anthraquinones and flavonoids. These Nigerian medicinal plants could be developed into cheap, safe and culturally acceptable standardized herbal products and may serve as a source of new molecules for broad-spectrum antimicrobial agents.

Study of the solvent effects on the molecular structure and Cdbnd O stretching vibrations of flurbiprofen

NASA Astrophysics Data System (ADS)

Tekin, Nalan; Pir, Hacer; Sagdinc, Seda

2012-12-01

The effects of 15 solvents on the C=O stretching vibrational frequency of flurbiprofen (FBF) were determined to investigate solvent-solute interactions. Solvent effects on the geometry and C=O stretching vibrational frequency, ν(C=O), of FBF were studied theoretically at the DFT/B3LYP and HF level in combination with the polarizable continuum model and experimentally using attenuated total reflection infrared spectroscopy (ATR-IR). The calculated C=O stretching frequencies in the liquid phase are in agreement with experimental values. Moreover, the wavenumbers of ν(C=O) of FBF in different solvents have been obtained and correlated with the Kirkwood-Bauer-Magat equation (KBM), the solvent acceptor numbers (ANs), and the linear solvation energy relationships (LSERs). The solvent-induced stretching vibrational frequency shifts displayed a better correlation with the LSERs than with the ANs and KBM.

Antimicrobial activity of silver nanoparticles impregnated wound dressing

NASA Astrophysics Data System (ADS)

Shinde, V. V.; Jadhav, P. R.; Patil, P. S.

2013-06-01

In this work, silver nanoparticles were synthesized by simple wet chemical reduction method. The silver nitrate was reduced by Sodium borohydride used as reducing agent and Poly (vinyl pyrrolidone) (PVP) as stabilizing agent. The formation of silver nanoparticles was evaluated by UV-visible spectroscope and transmission electron microscope (TEM). Absorption spectrum consist two plasmon peaks at 410 and 668 nm revels the formation of anisotropic nanoparticles confirmed by TEM. The formation of silver nanoparticles was also evidenced by dynamic light scattering (DLS) study. DLS showed polydisperse silver nanoparticles with hydrodynamic size 32 nm. Protecting mechanism of PVP was manifested by FT-Raman study. Silver nanoparticles were impregnated into wound dressing by sonochemical method. The Kirby-Bauer disc diffusion methods were used for antimicrobial susceptibility testing. The antimicrobial activity of the samples has been tested against gram-negative bacterium Escherichia coli and gram-positive bacterium Staphylococcus aureus.

Scepticism and doubt in science and science education: the complexity of global warming as a socio-scientific issue

NASA Astrophysics Data System (ADS)

Bryce, Tom G. K.; Day, Stephen P.

2014-09-01

This article looks critically at the complexity of the debate among climate scientists; the controversies in the science of global temperature measurement; and at the role played by consensus. It highlights the conflicting perspectives figuring in the mass media concerned with climate change, arguing that science teachers should be familiar with them, particularly given the sharply contested views likely to be brought into classroom discussion and the importance of developing intellectual scepticism and robust scientific literacy in students. We distinguish between rational scepticism and the pejorative meaning of the expression associated with attitudinal opposition to global warming—similar to the way in which Bauer (2006) contrasts micro- scepticism and macro- scepticism in reasoning generally. And we look closely and critically at the approaches which teachers might adopt in practice to teach about global warming at this difficult time.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wackerbarth, David

Sandia National Laboratories has developed a computer program to review, reduce and manipulate waveform data. PlotData is designed for post-acquisition waveform data analysis. PlotData is both a post-acquisition and an advanced interactive data analysis environment. PlotData requires unidirectional waveform data with both uniform and discrete time-series measurements. PlotData operates on a National Instruments' LabVIEW™ software platform. Using PlotData, the user can capture waveform data from digitizing oscilloscopes over a GPIB, USB and Ethernet interface from Tektronix, Lecroy or Agilent scopes. PlotData can both import and export several types of binary waveform files including, but not limited to, Tektronix .wmf files,more » Lecroy.trc files and xy pair ASCIIfiles. Waveform manipulation includes numerous math functions, integration, differentiation, smoothing, truncation, and other specialized data reduction routines such as VISAR, POV, PVDF (Bauer) piezoelectric gauges, and piezoresistive gauges such as carbon manganin pressure gauges.« less

The inspiration of astronomical phenomena (INSAP). Proceedings. Conference, Rocca di Papa (Italy), 27 Jun - 2 Jul 1994.

NASA Astrophysics Data System (ADS)

The papers concern the inspiration provided by astronomy to the fields of art, philosophy, religion and various human cultures. Individual papers cover the following topics: the Qur'anic conception of astronomical phenomena on Islamic civilization, the Milky Way and society, the mythology and ritual of India, the Varanasi Sun temples, celestial bodies meanings in pre-Hispanic Mexico, the celestial basis of civilization, Mexican eclipse imagery, Chinese dynastic ideology - astrological origins, NW Europe stone rows, stars and seasons in southern Africa, the Pleiades and Hesperides, stars and philosophy, the search for extraterrestrial life, the significance of the pre-Copernican revolution, Judaeo-Christian revelation, Maria Magdalena - the Morning Star, Chaucer's Canterbury Tales, stellar poetry, John Bauer's star-spangled fairy-tale world, Polish romantic poetry, the expansion of astronomical horizons, recent comet research and ancient sky implications, civilization Spenglerian model and punctuational crises, Anaxagoras and the scientist/laity interaction.

In-feed use of heavy metal micronutrients in U.S. swine production systems and its role in persistence of multidrug-resistant salmonellae.

PubMed

Medardus, Julius J; Molla, Bayleyegn Z; Nicol, Matthew; Morrow, W Morgan; Rajala-Schultz, Paivi J; Kazwala, Rudovick; Gebreyes, Wondwossen A

2014-04-01

The study aimed to characterize the role of heavy metal micronutrients in swine feed in emergence of heavy-metal-tolerant and multidrug-resistant Salmonella organisms. We conducted a longitudinal study in 36 swine barns over a 2-year period. The feed and fecal levels of Cu(2+) and Zn(2+) were measured. Salmonella was isolated at early and late finishing. MICs of copper sulfate and zinc chloride were measured using agar dilution. Antimicrobial susceptibility was tested using the Kirby-Bauer method, and 283 isolates were serotyped. We amplified pcoA and czcD genes that encode Cu(2+) and Zn(2+) tolerance, respectively. Of the 283 isolates, 113 (48%) showed Cu(2+) tolerance at 24 mM and 164 (58%) showed Zn(2+) tolerance at 8 mM. In multivariate analysis, serotype and source of isolates were significantly associated with Cu(2+) tolerance (P < 0.001). Fecal isolates were more likely to be Cu(2+) tolerant than those of feed origin (odds ratio [OR], 27.0; 95% confidence interval [CI], 2.8 to 250; P = 0.0042) or environmental origin (OR, 5.8), implying the significance of gastrointestinal selective pressure. Salmonella enterica serotypes Typhimurium and Heidelberg, highly significant for public health, had higher odds of having >20 mM MICs of Cu(2+) than did "other" serotypes. More than 60% of Salmonella isolates with resistance type (R-type) AmStTeKm (32 of 53) carried pcoA; only 5% with R-type AmClStSuTe carried this gene. czcD gene carriage was significantly associated with a higher Zn(2+) MIC (P < 0.05). The odds of having a high Zn(2+) MIC (≥8 mM) were 14.66 times higher in isolates with R-type AmClStSuTe than in those with R-type AmStTeKm (P < 0.05). The findings demonstrate strong association between heavy metal tolerance and antimicrobial resistance, particularly among Salmonella serotypes important in public health.

In-Feed Use of Heavy Metal Micronutrients in U.S. Swine Production Systems and Its Role in Persistence of Multidrug-Resistant Salmonellae

PubMed Central

Medardus, Julius J.; Molla, Bayleyegn Z.; Nicol, Matthew; Morrow, W. Morgan; Rajala-Schultz, Paivi J.; Kazwala, Rudovick

2014-01-01

The study aimed to characterize the role of heavy metal micronutrients in swine feed in emergence of heavy-metal-tolerant and multidrug-resistant Salmonella organisms. We conducted a longitudinal study in 36 swine barns over a 2-year period. The feed and fecal levels of Cu2+ and Zn2+ were measured. Salmonella was isolated at early and late finishing. MICs of copper sulfate and zinc chloride were measured using agar dilution. Antimicrobial susceptibility was tested using the Kirby-Bauer method, and 283 isolates were serotyped. We amplified pcoA and czcD genes that encode Cu2+ and Zn2+ tolerance, respectively. Of the 283 isolates, 113 (48%) showed Cu2+ tolerance at 24 mM and 164 (58%) showed Zn2+ tolerance at 8 mM. In multivariate analysis, serotype and source of isolates were significantly associated with Cu2+ tolerance (P < 0.001). Fecal isolates were more likely to be Cu2+ tolerant than those of feed origin (odds ratio [OR], 27.0; 95% confidence interval [CI], 2.8 to 250; P = 0.0042) or environmental origin (OR, 5.8), implying the significance of gastrointestinal selective pressure. Salmonella enterica serotypes Typhimurium and Heidelberg, highly significant for public health, had higher odds of having >20 mM MICs of Cu2+ than did “other” serotypes. More than 60% of Salmonella isolates with resistance type (R-type) AmStTeKm (32 of 53) carried pcoA; only 5% with R-type AmClStSuTe carried this gene. czcD gene carriage was significantly associated with a higher Zn2+ MIC (P < 0.05). The odds of having a high Zn2+ MIC (≥8 mM) were 14.66 times higher in isolates with R-type AmClStSuTe than in those with R-type AmStTeKm (P < 0.05). The findings demonstrate strong association between heavy metal tolerance and antimicrobial resistance, particularly among Salmonella serotypes important in public health. PMID:24487542

A persistent antimicrobial resistance pattern and limited methicillin-resistance-associated genotype in a short-term Staphylococcus aureus carriage isolated from a student population.

PubMed

Mat Azis, Norhidayah; Pung, Hui P; Abdul Rachman, Abdul R; Amin Nordin, Syafinaz; Sarchio, Seri N E; Suhaili, Zarizal; Mohd Desa, Mohd N

The aim of the present study was to assess and compare the antimicrobial susceptibility pattern against a panel of antibiotics and molecular and methicillin resistance-associated genotypes of 120 carriage S. aureus isolates previously isolated from a student population at two isolation events within a one-month interval. The antibiotic susceptibility of isolates was determined using the Kirby-Bauer disc-diffusion method (cefoxitin by Etest). The MRSA was screened using polymerase chain reaction for the presence of the mecA gene. The mecA-positive isolates were subjected to staphylococcal cassette chromosome (SCC) mec typing, multilocus sequence typing (MLST) and eBURST analysis. All isolates were characterized for the presence of the Panton-Valentine leukocidin (PVL) gene, an enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) pattern and the spa type. For the two occasions where S. aureus was isolated, the highest frequency of resistance was observed for penicillin (70% and 65%, respectively), with a lower rate against erythromycin and tetracycline (<12%). All isolates were susceptible to ciprofloxacin and gentamycin. As for methicillin resistance, eight isolates had minimum inhibitory concentrations (MIC) of resistant categories, but 10 isolates (8.33%) were positive for the mecA gene. The mecA-positive isolates belonged to SCCmec types I (n=9) and V (n=1). MLST was resolved for only three MRSAs, ST508 (n=1), ST88 (n=1) and ST96 (n=1). The results of the eBURST analysis showed that the MRSA isolates analyzed in the present study were potentially related to MRSA identified in other countries. Approximately half of the persistent S. aureus carriers harbored S. aureus of a similar spa type in the respective individuals during both isolation events. A persistent antimicrobial pattern and limited distinct MRSAs were observed over the short study period. The latter frequently exhibited SCCmec type I, commonly associated with hospital-acquired (HA) characteristics, but further delineation is needed to justify the origins of these bacteria. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Observation of the Kaiser Effect Using Noble Gas Release Signals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauer, Stephen J.

The Kaiser effect was defined in the early 1950s (Kaiser 1953) and was extensively reviewed and evaluated by Lavrov (2002) with a view toward understanding stress estimations. The Kaiser effect is a stress memory phenomenon which has most often been demonstrated in rock using acoustic emissions. During cyclic loading–unloading–reloading, the acoustic emissions are near zero until the load exceeds the level of the previous load cycle. Here, we sought to explore the Kaiser effect in rock using real-time noble gas release. Laboratory studies using real-time mass spectrometry measurements during deformation have quantified, to a degree, the types of gases releasedmore » (Bauer et al. 2016a, b), their release rates and amounts during deformation, estimates of permeability created from pore structure modifications during deformation (Gardner et al. 2017) and the impact of mineral plasticity upon gas release. We found that noble gases contained in brittle crystalline rock are readily released during deformation.« less

Evaluation of anti-plaque microbial activity of Azadirachta indica (neem oil) in vitro: A pilot study

PubMed Central

Elavarasu, Sugumari; Abinaya, P.; Elanchezhiyan, S.; Thangakumaran; Vennila, K.; Naziya, K. B.

2012-01-01

Background: Probably microbial plaque is the main etiology for periodontal tissue inflammation. Various chemical agents have been evaluated over the years with respect to their antimicrobial effects in the oral cavity. However, all are associated with side effects that prohibit regular long-term use. Therefore, the effectiveness of Azadirachta indica (neem) against plaque formation is considered to be vital, with lesser side effects. The aim of the present study is to evaluate and prove the antimicrobial activity of neem using plaque samples. Materials and Methods: Culture was prepared using brain heart infusion broth reagent. Dental plaque samples were used for that. Kirby–Bauer antimicrobial susceptibility test procedure was carried away with the sample. Neem oil was kept in the agar plate with culture and the diameter of inhibition zones was calculated. Results: Results showed inhibition zones on the agar plate around neem oil. Conclusion: Study shows definite antiplaque activity of neem oil. PMID:23066297

Antibiotic resistance monitoring in Vibrio spp. isolated from rearing environment and intestines of abalone Haliotis diversicolor.

PubMed

Wang, R X; Wang, J Y; Sun, Y C; B L Yang; A L Wang

2015-12-30

546 Vibrio isolates from rearing seawater (292 strains) and intestines of abalone (254 strains) were tested to ten antibiotics using Kirby-Bauer diffusion method. Resistant rates of abalone-derived Vibrio isolates to chloramphenicol (C), enrofloxacin (ENX) and norfloxacin (NOR) were <28%, whereas those from seawater showed large fluctuations in resistance to each of the tested antibiotics. Many strains showed higher resistant rates (>40%) to kanamycin (KNA), furazolidone (F), tetracycline (TE), gentamicin (GM) and rifampin (RA). 332 isolates from seawater (n=258) and abalone (n=74) were resistant to more than three antibiotics. Peaked resistant rates of seawater-derived isolates to multiple antibiotics were overlapped in May and August. Statistical analysis showed that pH had an important effect on resistant rates of abalone-derived Vibrio isolates to RA, NOR, and ENX. Salinity and dissolved oxygen were negatively correlated with resistant rates of seawater-derived Vibrio isolates to KNA, RA, and PG. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of glyphosate herbicide on the gastrointestinal microflora of Hawaiian green turtles (Chelonia mydas) Linnaeus.

PubMed

Kittle, Ronald P; McDermid, Karla J; Muehlstein, Lisa; Balazs, George H

2018-02-01

In Hawaii, glyphosate-based herbicides frequently sprayed near shorelines may be affecting non-target marine species. Glyphosate inhibits aromatic amino acid biosynthesis (shikimate pathway), and is toxic to beneficial gut bacteria in cattle and chickens. Effects of glyphosate on gut bacteria in marine herbivorous turtles were assessed in vitro. When cultures of mixed bacterial communities from gastrointestinal tracts of freshly euthanized green turtles (Chelonia mydas), were exposed for 24h to six glyphosate concentrations (plus deionized water control), bacterial density was significantly lower at glyphosate concentrations≥2.2×10 -4 gL -1 (absorbance measured at 600nm wavelength). Using a modified Kirby-Bauer disk diffusion assay, the growth of four bacterial isolates (Pantoea, Proteus, Shigella, and Staphylococcus) was significantly inhibited by glyphosate concentrations≥1.76×10 -3 gL -1 . Reduced growth or lower survival of gut bacteria in green turtles exposed to glyphosate could have adverse effects on turtle digestion and overall health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Observation of the Kaiser Effect Using Noble Gas Release Signals

DOE PAGES

Bauer, Stephen J.

2017-10-24

The Kaiser effect was defined in the early 1950s (Kaiser 1953) and was extensively reviewed and evaluated by Lavrov (2002) with a view toward understanding stress estimations. The Kaiser effect is a stress memory phenomenon which has most often been demonstrated in rock using acoustic emissions. During cyclic loading–unloading–reloading, the acoustic emissions are near zero until the load exceeds the level of the previous load cycle. Here, we sought to explore the Kaiser effect in rock using real-time noble gas release. Laboratory studies using real-time mass spectrometry measurements during deformation have quantified, to a degree, the types of gases releasedmore » (Bauer et al. 2016a, b), their release rates and amounts during deformation, estimates of permeability created from pore structure modifications during deformation (Gardner et al. 2017) and the impact of mineral plasticity upon gas release. We found that noble gases contained in brittle crystalline rock are readily released during deformation.« less

KSC-04PD-0007

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., places samples of onion tissue in the elemental analyzer, which analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASAs ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASAs Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASAs Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

Frontiers of X-Ray Astronomy

NASA Astrophysics Data System (ADS)

Fabian, Andrew C.; Pounds, Kenneth A.; Blandford, Roger D.

2004-07-01

Preface; 1. Forty years on from Aerobee 150: a personal perspective K. Pounds; 2. X-ray spectroscopy of astrophysical plasmas S. M. Kahn, E. Behar, A. Kinkhabwala and D. W. Savin; 3. X-rays from stars M. Gudel; 4. X-ray observations of accreting white-dwarf systems M. Cropper, G. Ramsay, C. Hellier, K. Mukai, C. Mauche and D. Pandel; 5. Accretion flows in X-ray binaries C. Done; 6. Recent X-ray observations of supernova remnants C. R. Canizares; 7. Luminous X-ray sources in spiral and star-forming galaxies M. Ward; 8. Cosmological constraints from Chandra observations of galaxy clusters S. W. Allen; 9. Clusters of galaxies: a cosmological probe R. Mushotzky; 10. Obscured active galactic nuclei: the hidden side of the X-ray Universe G. Matt; 11. The Chandra Deep Field-North Survey and the cosmic X-ray background W. N. Brandt, D. M. Alexander, F. E. Bauer and A. E. Hornschemeier; 12. Hunting the first black holes G. Hasinger; 13. X-ray astronomy in the new millennium: a summary R. D. Blandford.

Bacteria profile and antibiogram of the bacteria isolated from the exposed pulp of dog canine teeth.

PubMed

Almansa Ruiz, José Carlos; Jonker, Annelize; Bosman, Anna-Mari; Steenkamp, Gerhard

2018-04-27

Twenty-seven microbiological samples were taken from root canals (RC) of the canine teeth of 20 dogs where the pulps were non-vital and exposed due to complicated crown fractures. These pulps were cultured for aerobic/anaerobic bacteria. Antimicrobial susceptibility of isolates was determined using the Kirby-Bauer diffusion test. A total of 49 cultivable isolates, belonging to 27 different microbial species and 18 different genera, were recovered from the 27 RCs sampled. Twenty (40.81 per cent) of the cultivable isolates were Gram positive while 29 (59.19 per cent) were Gram negative. Facultative anaerobes were the most common bacteria (77.56 per cent). Aerobic isolates represented 18.36 per cent, and strict anaerobes 4.08 per cent. The antimicrobials with the highest in vitro efficacy were gentamicin (100 per cent) and enrofloxacin (93.32 per cent). © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Chemical composition and antibacterial activity of the essential oil of Drimys granadensis L.f. leaves from Colombia.

PubMed

Gaviria, Mauricio; Quijano, Clara; Pino, Jorge; Madriñán, Santiago

2011-03-01

Drimys granadensis L.f., a native plant from Colombia, has been included in the Vademecum de Plantas Medicinales de Colombia by the Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, due to its widespread use in the folk medicine for the treatment of gastrointestinal ailments. The chemical composition of the essential oil of Drimys granadensis obtained by hydrodistillation of the leaves was analyzed by GC and GC/MS analyses. A total of 85 components were identified, with the major compounds germacrene D (1, 14.7%), sclarene (9.5%), a-cadinol (7.3%), longiborneol acetate (2, 6.3%), drimenol (4.2%), (Z)-β-ocimene (3, 4.2%), a-pinene (4, 3.2%), and β-elemene (5, 2.7%). The essential oil was also tested against eight bacteria using the Kirby-Bauer disk-diffusion method. Most of the Gram-positive bacteria tested were susceptible to the D. granadensis essential oil, while the Gram-negative bacteria tested were not.

NEOWISE Reactivated Mission Cometary CO+CO2: Preliminary Results from Years 1 through 3

NASA Astrophysics Data System (ADS)

Bauer, James M.; Grav, Tommy; Mainzer, Amy K.; Kramer, Emily A.; Masiero, Joseph R.; Kelley, Michael S.; Nugent, Carrie R.; Sonnett, Sarah M.; Fernandez, Yanga R.; Lisse, Casey M.; Meech, Karen Jean; Rosser, Joshua David; Walker, Russell G.; Wright, Edward L.; NEOWISE Team

2017-10-01

NEOWISE has utilized the WISE spacecraft data to provided an unpresidented number of radiometrically determined diameters and mid-infrared photometric observations of small bodies. During the WISE prime mission (January 2010 - January 2011) over 158000 solar system objects were detected by the spacecraft[1] before it was placed in hibernation in February of 2011. Of these, 164 comets were detected and characterized with respect to their dust production and particle size[2,3], CO+CO2 production[4], and diameters[5].The WISE spacecraft was reactived in 2013 and survey operations were restarted with the express purpose of searching for and characterizing solar system objects[6]. Re-named NEOWISE, the spacecraft continues to image the sky for Near-Earth objects and other small bodies at wavelengths of 3.4 and 4.6 μm, and is now into year 4 of its reactivated survey. The first 3 years of the NEOWISE reactivated mission produced detections of 11,800 objects[7,8], with a larger fraction of comets than during the cryogenic mission. Over 110 comets have been detected in the first 3 years of the reactivated survey. With NEOWISE's wavelength coverage, the survey is sensative to CO2 emission lines that are obscured by Earth's atmosphere and faint CO emission that is not easily detected from groundbased observations. We will present a preliminary analysis of this 3-year data set of comets regarding CO and CO2 production rates, tracing the behavior of these emissions at different heliocentric distances for several comets and for the ensemble of comets that show excess emission relative to dust that is indicative of CO+CO2 emission, approximately two thirds of the entire sample. We will also place these in the context of the Spitzer mission data set of targeted comet observations[9].[1] Mainzer, A. et al. 2011a, ApJ, 731, 53.[2] Kramer, E. 2014, PhD Dissertation, Univ. Central Florida.[3] Kramer, E. et al. 2017, ApJ, 838, 58.[4] Bauer, J. M. et al. 2015, ApJ, 814, 85.[5] Bauer, J. M. et al. 2017, J, 154, 53.[6] Mainzer, A. et al. 2014, ApJ, 792, 30.[7] Cutri, R. M. et al. 2017 (http://wise2.ipac.caltech.edu/docs/release/neowise/expsup)[8] Masiero, J. et al. 2017, submitted.[9] Kelley, M. S. et al. 2017, AAS DPS meeting.

Global solutions to the electrodynamic two-body problem on a straight line

NASA Astrophysics Data System (ADS)

Bauer, G.; Deckert, D.-A.; Dürr, D.; Hinrichs, G.

2017-06-01

The classical electrodynamic two-body problem has been a long standing open problem in mathematics. For motion constrained to the straight line, the interaction is similar to that of the two-body problem of classical gravitation. The additional complication is the presence of unbounded state-dependent delays in the Coulomb forces due to the finiteness of the speed of light. This circumstance renders the notion of local solutions meaningless, and therefore, straightforward ODE techniques cannot be applied. Here, we study the time-symmetric case, i.e., the Fokker-Schwarzschild-Tetrode (FST) equations, comprising both advanced and retarded delays. We extend the technique developed in Deckert and Hinrichs (J Differ Equ 260:6900-6929, 2016), where existence of FST solutions was proven on the half line, to ensure global existence—a result that had been obtained by Bauer (Ein Existenzsatz für die Wheeler-Feynman-Elektrodynamik, Herbert Utz Verlag, München, 1997). Due to the novel technique, the presented proof is shorter and more transparent but also relies on the idea to employ asymptotic data to characterize solutions.

Biogenic nano-scale silver particles by Tephrosia purpurea leaf extract and their inborn antimicrobial activity

NASA Astrophysics Data System (ADS)

Ajitha, B.; Ashok Kumar Reddy, Y.; Reddy, P. Sreedhara

2014-03-01

In this paper we report the green synthesis of silver nanoparticles (Ag NPs) using Tephrosia purpurea leaf extract. The biomolecules present in the leaf extract are responsible for the formation of Ag NPs and they found to play dual role of both reducing as well as capping agents. The high crystallinity of Ag NPs is evident from bright circular spot array of SAED pattern and diffraction peaks in XRD profile. The synthesized Ag NPs are found to be nearly spherical ones with size approximately ∼20 nm. FTIR spectrum evidences the presence of different functional groups of biomolecules participated in encapsulating Ag NPs and the possible mechanism of Ag NPs formation was also suggested. Appearance of yellow color and surface plasmon resonance (SPR) peak at 425 nm confirms the Ag NPs formation. PL spectra showed decrement in luminescence intensity at higher excitation wavelengths. Antimicrobial activity of Ag NPs showed better inhibitory activity towards Pseudomonas spp. and Penicillium spp. compared to other test pathogens using standard Kirby-Bauer disc diffusion assay.

[Antimicrobial susceptibility of animal and food isolates of Salmonella enterica].

PubMed

Junod, Tania; López-Martin, Juana; Gädicke, Paula

2013-03-01

Bacterial resistance to one or more antimicrobiak is worrisome. To determine the susceptibility to antimicrobials of Salmonella entérica isolates from animáis and food, from the Laboratory of Veterinary Microbiology at the University of Concepción. The samples were isolated according to traditional microbiological methods standardized protocols. Resistance was determined by the Kirby-Bauer method and minimal inhibitory concentration (MIC), following Clinical and Laboratory Standards Institute recommendations (2008). Nine serotypes were identified among the 68 isolates. Strains were resistant to one or more antibiotics and 11 patterns of resistance were identified. Multidrug resistance (MDR) was observed in 20.5% of the strains tested. The most common was Oxytetracycline resistance (69.1%). Infood, the predominant serotype was S. Derby (2.9%) and S. Senftenberg (2.9%), which is commonly found infood intended for animal consumption. In samples of animal origin, the predominant serotypes were S. infantis (33.8%) and S. Group E (3.9;-;-) (23.5%). The frequeney of resistance found and the impending risk that these strains could reach humans through the food chain, should prompt a follow-up study of this pathogen.

A study of bacterial pathogens and antibiotic susceptibility patterns in chronic suppurative otitis media.

PubMed

Mofatteh, M R; Shahabian Moghaddam, F; Yousefi, M; Namaei, M H

2018-01-01

To assess the frequency of bacterial agents in chronic suppurative otitis media and the antibiotic susceptibility patterns of isolates among patients. A total of 185 patients clinically diagnosed with chronic suppurative otitis media were interviewed and middle-ear effusion samples were collected using sterile swabs. All bacterial isolates were identified by conventional microbiological methods. Antibiotic susceptibility patterns of the isolates were determined by Kirby-Bauer disc diffusion. Staphylococci spp. (64.9 per cent) were the most prevalent bacteria isolated, followed by Klebsiella spp. (12.9 per cent) and Pseudomonas aeruginosa (10.3 per cent). The most effective antibiotic for treatment of bacterial chronic suppurative otitis media was ciprofloxacin. Statistical analysis showed no significant difference in bacterial infestations among chronic suppurative otitis media patients and the antimicrobial susceptibility patterns of the bacterial isolates based on gender and age (p > 0.05). Our findings highlight the importance of a continuous and periodic evaluation of the bacteriological profile and antibiotic susceptibility patterns in chronic suppurative otitis media patients for efficacious treatment of the infection.

The Structure of Plant Cell Walls

PubMed Central

Wilder, Barry M.; Albersheim, Peter

1973-01-01

The molecular structure and chemical properties of the hemicellulose present in the isolated cell walls of suspension cultures of sycamore (Acer pseudoplatanus) cells has recently been described by Bauer et al. (Plant Physiol. 51: 174-187). The hemicellulose of the sycamore primary cell wall is a xyloglucan. This polymer functions as an important cross-link in the structure of the cell wall; the xyloglucan is hydrogen-bonded to cellulose and covalently attached to the pectic polymers. The present paper describes the structure of a xyloglucan present in the walls and in the extracellular medium of suspension-cultured Red Kidney bean (Phaseolus vulgaris) cells and compares the structure of the bean xyloglucan with the structure of the sycamore xyloglucan. Although some minor differences were found, the basic structure of the xyloglucans in the cell walls of these distantly related species is the same. The structure is based on a repeating heptasaccharide unit which consists of four residues of β-1, 4-linked glucose and three residues of terminal xylose linked to the 6 position of three of the glucosyl residues. PMID:16658434

Anticipatory dynamics of biological systems: from molecular quantum states to evolution

NASA Astrophysics Data System (ADS)

Igamberdiev, Abir U.

2015-08-01

Living systems possess anticipatory behaviour that is based on the flexibility of internal models generated by the system's embedded description. The idea was suggested by Aristotle and is explicitly introduced to theoretical biology by Rosen. The possibility of holding the embedded internal model is grounded in the principle of stable non-equilibrium (Bauer). From the quantum mechanical view, this principle aims to minimize energy dissipation in expense of long relaxation times. The ideas of stable non-equilibrium were developed by Liberman who viewed living systems as subdivided into the quantum regulator and the molecular computer supporting coherence of the regulator's internal quantum state. The computational power of the cell molecular computer is based on the possibility of molecular rearrangements according to molecular addresses. In evolution, the anticipatory strategies are realized both as a precession of phylogenesis by ontogenesis (Berg) and as the anticipatory search of genetic fixation of adaptive changes that incorporates them into the internal model of genetic system. We discuss how the fundamental ideas of anticipation can be introduced into the basic foundations of theoretical biology.

KSC-04PD-0008

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- In the Space Life Sciences (SLS) Lab, Jan Bauer, with Dynamac Corp., weighs samples of onion tissue for processing in the elemental analyzer behind it. The equipment analyzes for carbon, hydrogen, nitrogen and sulfur. The 100,000 square-foot SLS houses labs for NASAs ongoing research efforts, microbiology/microbial ecology studies and analytical chemistry labs. Also calling the new lab home are facilities for space flight-experiment and flight-hardware development, new plant growth chambers, and an Orbiter Environment Simulator that will be used to conduct ground control experiments in simulated flight conditions for space flight experiments. The SLS Lab, formerly known as the Space Experiment Research and Processing Laboratory or SERPL, provides space for NASAs Life Sciences Services contractor Dynamac Corporation, Bionetics Corporation, and researchers from the University of Florida. NASAs Office of Biological and Physical Research will use the facility for processing life sciences experiments that will be conducted on the International Space Station. The SLS Lab is the magnet facility for the International Space Research Park at KSC being developed in partnership with Florida Space Authority.

Killing bacteria within biofilms by sustained release of tetracycline from triple-layered electrospun micro/nanofibre matrices of polycaprolactone and poly(ethylene-co-vinyl acetate).

PubMed

Alhusein, Nour; De Bank, Paul A; Blagbrough, Ian S; Bolhuis, Albert

2013-12-01

We report the controlled release of the antibiotic tetracycline (tet) HCl from a triple-layered electrospun matrix consisting of a central layer of poly(ethylene-co-vinyl acetate (PEVA) sandwiched between outer layers of poly-ε-caprolactone (PCL). These micro/nanofibre layers with tet successfully encapsulated (essentially quantitatively at 3 and 5 % w/w) in each layer, efficiently inhibited the growth of a panel of bacteria, including clinical isolates, as shown by a modified Kirby-Bauer disc assay. Furthermore, they demonstrated high biological activity in increasingly complex models of biofilm formation (models that are moving closer to the situation in a wound) by stopping biofilm formation, by killing preformed biofilms and killing mature, dense biofilm colonies of Staphylococcus aureus MRSA252. Tet is clinically useful with potential applications in wound healing and especially in complicated skin and skin-structure infections; electrospinning provides good encapsulation efficiency of tet within PCL/PEVA/PCL polymers in micro/nanofibre layers which display sustained antibiotic release in formulations that are anti-biofilm.

Impact of concomitant Y and Mn substitution on superconductivity in La1 -yYyFe1 -xMnxAsO0.89F0.11

NASA Astrophysics Data System (ADS)

Kappenberger, Rhea; Hammerath, Franziska; Rousse, Pierre; Afrassa, Mesfin Asfaw; Haghighi, M. Hossein; Kamusella, Sirko; Prando, Giacomo; Lamura, Gianrico; Wolter, Anja U. B.; Moroni, Matteo; Sanna, Samuele; Carretta, Pietro; Hess, Christian; Grafe, Hans-Joachim; Klauss, Hans-Henning; Wurmehl, Sabine; Büchner, Bernd

2018-02-01

We discuss the impact of concomitant substitution of Fe by Mn and La by Y in optimally F-doped LaFeAsO0.89F0.11 . Mn has a known poisoning effect on superconductivity which is particularly strong in the La1111 system, where 0.2% of Mn were reported to completely suppress superconductivity. Through isovalent substitution of La by the much smaller Y we are able to inflict chemical pressure on the structure, which we show is stabilizing the superconducting state, resulting in a drastically larger amount of Mn needed to completely quench superconductivity. Interestingly, we find that the lattice parameter c changes significantly even for small amounts of Mn substitution within a series, which is unexpected taking only the differences between ionic radii into account. We discuss our findings in the light of electron localization caused by small amounts of paramagnetic Mn impurities in La1 -yYyFe1 -xMnxAsO0.89F0.11 also indicated by resistivity and Mößbauer measurements.

An eight-year study of Shigella species in Beijing, China: serodiversity, virulence genes, and antimicrobial resistance.

PubMed

Qu, Mei; Zhang, Xin; Liu, Guirong; Huang, Ying; Jia, Lei; Liang, Weili; Li, Xitai; Wu, Xiaona; Li, Jie; Yan, Hanqiu; Kan, Biao; Wang, Quanyi

2014-07-14

This study was conducted to determine the prevalence of serotypes, virulence factors, and antimicrobial resistance patterns of Shigella spp. in Beijing, China, from 2004 to 2011. Real-time PCR assays were used to detect virulent genes, and the Kirby-Bauer disk diffusion method was used to evaluate antimicrobial resistance. Among the total of 1,652 Shigella isolates, S. sonnei (57.1%) was the predominant species, followed by S. flexneri (42.3%), S. dysenteriae (0.4%), and S. boydii (0.2%). Nineteen serotypes were discovered among S. flexneri strains. The virulence gene ipaH was the most frequent, followed by sen and set. The presence of set showed significant difference in two dominant serogroups, S. flexneri and S. sonnei. Over 90% of Shigella isolates showed resistance to at least three drugs with widened spectrum. High-level antimicrobial resistance to single and multiple antibiotics was more common among S. sonnei than S. flexneri. There was an obvious serotype change and a dramatic increase of antibiotic resistance in Shigella prevalence in Beijing.

Morphology and inhibition performance of Ag thin film as antimicrobial coating deposited by RF-PVD on 316 L stainless steel

NASA Astrophysics Data System (ADS)

Purniawan, A.; Khrisna, Y. S. A.; Rasyida, A.; Atmono, T. M.

2018-04-01

Foreign body related infection (FBRIs) is caused by forming biofilm of bacterial colony of medical equipment surfaces. In many cases, the FBRIs is still happened on the surface after medical sterilization process has been performed. In order to avoid the case, surface modification by antimicrobial coating was used. In this work, we present silver (Ag) thin film on 316 L stainless steel substrate surface was deposited using Radio Frequency Sputtering PVD (RF-PVD). The morphology of Ag thin film were characterized using SEM-EDX. Surface roughness of the thin film was measured by AFM. In addition, Kirby Bauer Test in Escherichia coli (E. coli) was conducted in order to evaluate the inhibition performance of the Ag thin film antimicrobial coating. Based on SEM and AFM results show that the particle size is increased from 523 nm to 708 nm and surface roughness from 9 to 20 nm for deposition time 10 minutes to 20 minutes, respectively. In addition, the inhibition layer of the coating is about 29 mm.

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

PubMed Central

Sathish, Kumar SR; Kokati, Venkata Bhaskara Rao

2012-01-01

Objective To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA). Methods Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology. Results Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key. Conclusions The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms. PMID:23569848

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus.

PubMed

Sathish, Kumar S R; Kokati, Venkata Bhaskara Rao

2012-10-01

To investigate the antibacterial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus (MDRSA). Fifty one actinobacterial strains were isolated from salt pans soil, costal area in Kothapattanam, Ongole, Andhra Pradesh. Primary screening was done using cross-streak method against MDRSA. The bioactive compounds are extracted from efficient actinobacteria using solvent extraction. The antimicrobial activity of crude and solvent extracts was performed using Kirby-Bauer method. MIC for ethyl acetate extract was determined by modified agar well diffusion method. The potent actinobacteria are identified using Nonomura key, Shirling and Gottlieb 1966 with Bergey's manual of determinative bacteriology. Among the fifty one isolates screened for antibacterial activity, SRB25 were found efficient against MDRSA. The ethyl acetate extracts showed high inhibition against test organism. MIC test was performed with the ethyl acetate extract against MDRSA and found to be 1 000 µg/mL. The isolated actinobacteria are identified as Streptomyces sp with the help of Nonomura key. The current investigation reveals that the marine actinobacteria from salt pan environment can be able to produce new drug molecules against drug resistant microorganisms.

Correlation Between Cometary Gas/Dust Ratios and Heliocentric Distance

NASA Astrophysics Data System (ADS)

Harrington, Olga; Womack, Maria; Lastra, Nathan

2017-10-01

We compiled CO-based gas/dust ratios for several comets out to heliocentric distances, rh, of 8 au to probe whether there is a noticeable change in comet behavior over the range that water-ice sublimation starts. Previously, gas/dust ratios were calculated for an ensemble of comets using Q(CO2)/efp values derived from infrared measurements, which showed that the gas/dust ratio follows a rh-2 within 4 AU, but is flat at greater distances (Bauer et al. 2015). Our project focuses on gas/dust ratios for which CO is assumed to be the dominant gas, in order to test whether similar breaks in slope occur for CO. The gas/dust ratios were calculated from measurements of CO production rates (mostly from millimeter-wavelength spectroscopy) and reflected sunlight of comets (mostly via reported visual magnitudes of dusty comets). We present our new CO-based gas/dust ratios at different heliocentric distances, compare them to existing CO2-based gas/dust ratios, and discuss implications for CO-driven and CO2-driven activity. We discuss O.H. acknowledges support from the Hartmann Student Travel Grant program. M.W. acknowledges support from NSF grant AST-1615917.

Resonant nature of intrinsic defect energy levels in PbTe revealed by infrared photoreflectance spectroscopy

NASA Astrophysics Data System (ADS)

Zhang, Bingpo; Cai, Chunfeng; Jin, Shuqiang; Ye, Zhenyu; Wu, Huizhen; Qi, Zhen

2014-07-01

Step-scan Fourier-transform infrared photoreflectance and modulated photoluminescence spectroscopy were used to characterize the optical transitions of the epitaxial PbTe thin film grown by molecular beam epitaxy on BaF2 (111) substrate in the vicinity of energy gap of lead telluride at 77 K. It is found that the intrinsic defect energy levels in the electronic structure are of resonant nature. The Te-vacancy energy level is located above the conduction band minimum by 29.1 meV. Another defect (VX) energy level situated below valance band maximum by 18.1 meV is also revealed. Whether it is associated with the Pb vacancy is still not clear. It might also be related to the misfit dislocations stemming from the lattice mismatch between PbTe and BaF2 substrate. The experimental results support the theory prediction (N. J. Parada and G. W. Pratt, Jr., Phys. Rev. Lett. 22, 180 (1969), N. J. Parada, Phys. Rev. B 3, 2042 (1971)) and are consistent with the reported Hall experimental results (G. Bauer, H. Burkhard, H. Heinrich, and A. Lopez-Otero, J. Appl. Phys. 47, 1721 (1976)).

Purification of heavy metal loaded wastewater from electroplating industry under synthesis of delafossite (ABO2) by "Lt-delafossite process".

PubMed

John, Melanie; Heuss-Aßbichler, Soraya; Ullrich, Aladin; Rettenwander, Daniel

2016-09-01

In this study we present a new, environmental friendly and economic method, called Lt-delafossite process to treat industrial wastewater (initial Cu(2+)-concentrations of 1-15.6 g/l) by subsequent synthesis of nano-crystalline (doped) delafossite (CuFeO2) solely by precipitation and ageing at temperatures between 50 °C and 90 °C. The reached water purification rates are exclusively ≥99.99% for both wastewater models and wastewaters from electroplating industry. We succeeded to synthesize a mixture of 3R and 2H delafossite at 50 °C after 90 h and ≥70 °C after 16 h of ageing directly from industrial wastewater without any additional phases. In all cases green rust (GR), a Fe(II-III) layered double hydroxysulphate, Cu2O (cuprite) and Fe10O14(OH)2 (ferrihydrite) precipitates first. During ageing of the residues the metastable phases transform to delafossite. The residues are characterized by XRD, FTIR, SEM, TEM, VFTB and Mößbauer measurements. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nasal carriage of Methicillin- and Mupirocin-resistant S. aureus among health care workers in a tertiary care hospital.

PubMed

Agarwal, Loveleena; Singh, Amit Kumar; Sengupta, Chandrim; Agarwal, Amitabh

2015-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) ranks top among the nosocomial pathogens. Nasal formulation of mupirocin is found to eradicate MRSA from colonized individuals, but the emergence of resistant strains is a matter of concern. Nasal swabs were collected from 200 health care workers (HCWs) who were screened for MRSA. Kirby-Bauer disc diffusion method was used to perform antibiotic susceptibility test. MRSA detection was done using a cefoxitin 30 µg disc and interpreted according to the Clinical and Laboratory Standards Institute guidelines. Determination of mupirocin resistance was performed using Epsilometer test (E-test). About 14% of HCWs showed nasal carriage of MRSA. Nursing orderlies were the predominant carriers. E-test showed four mupirocin resistant isolates. The antibiogram of the MRSA isolates revealed the higher resistance to antibiotics as compared to methicillin-sensitive Staphylococcus aureus. All the MRSA isolates were sensitive to linezolid. HCWs in our hospital showed high nasal carriage rate of MRSA, particularly the nursing orderlies which is statistically significant. It is advisable to detect mupirocin resistance among the isolates obtained from the HCWs so that in case of resistance, alternative treatment should be sought.

Applications of compact accelerator-driven neutron sources: An updated assessment from the perspective of materials research in Italy

DOE PAGES

Andreani, C.; Anderson, I. S.; Carpenter, J. M.; ...

2014-12-24

In 2005 the International Atomic Energy Agency (IAEA) in Vienna published a report [1] on ‘Development Opportunities of Small and Medium Scale Accelerator Driven Neutron Sources’ which summarized the prospect of smaller sources in supporting the large spallation neutron sources for materials characterization and instrumentation, a theme advocated by Bauer, Clausen, Mank, and Mulhauser in previous publications [2-4]. In 2010 the Union for Compact Accelerator-driven Neutron Sources (UCANS) was established [5], galvanizing cross-disciplinary collaborations on new source and neutronics development and expanded applications based on both slow-neutron scattering and other neutron-matter interactions of neutron energies ranging from 10⁻⁶ to 10²more » MeV [6]. Here, we first cover the recent development of ongoing and prospective projects of compact accelerator-driven neutron sources (CANS) but concentrate on prospective accelerators currently proposed in Italy. Two active R&D topics, irradiation effects on electronics and cultural heritage studies, are chosen to illustrate the impact of state-of-the-art CANS on these programs with respect to the characteristics and complementarity of the accelerator and neutronics systems as well as instrumentation development.« less

[Phenotypic and genotypic characterization of Vibrio cholerae O1].

PubMed

Giono-Cerezo, S; Rodríguez Angeles, M G; Gutiérrez-Cogco, L; Valdespino-Gómez, J L

1994-01-01

We made 52180 tests for isolation and identification of toxigenic V. cholerae O1 from rectal swabs and reference strains. We isolated 17.6% V. cholerae O1 strains in 1991, 43.5% in 1992 and 38.9% in 1993. The main serovar in 1991 was Inaba, whereas in 1993 a similar percentage was serovar Ogawa. The phenotype of V. cholerae strains was determined by hemolysis test, Voges-Proskauer test, polymyxin B resistance and phages 4 and 5 resistance. All of the mexican strains were El Tor. There were 2.9-0.75% hemolytic strains from 1991 to 1993, but they were negative when the test was made in tube with human erythrocytes. The resistotypes were performed in 24526 selected strains by Kirby-Bauer method and MIC tests. All of the strains were sensitive, except more than 100 strains isolated in Veracruz that were resistant to tetracycline and doxycycline. Detection of cholera toxin was made by ELISA and on culture of Vero and CHO cells. All the V. cholerae O1 strains were toxigenic. The genotype was determined by PCR and ribotyping. The PCR amplified one 564 pb fragment on V. cholerae O1. The ribotypes of mexican strains were 5 and 6a.

Anti-mycobacterial activity of marine fungus-derived 4-deoxybostrycin and nigrosporin.

PubMed

Wang, Cong; Wang, Juan; Huang, Yuhong; Chen, Hong; Li, Yan; Zhong, Lili; Chen, Yi; Chen, Shengping; Wang, Jun; Kang, Juling; Peng, Yi; Yang, Bin; Lin, Yongcheng; She, Zhigang; Lai, Xiaomin

2013-01-29

4-Deoxybostrycin is a natural anthraquinone compound isolated from the Mangrove endophytic fungus Nigrospora sp. collected from the South China Sea. Nigrosporin is the deoxy-derivative of 4-deoxybostrycin. They were tested against mycobacteria, especially Mycobacterium tuberculosis. In the Kirby-Bauer disk diffusion susceptibility test, they both had inhibition zone sizes of over 25 mm. The results of the absolute concentration susceptibility test suggested that they had inhibitory effects against mycobacteria. Moreover, 4-deoxybostrycin exhibited good inhibition which was even better than that of first line anti-tuberculosis (TB) drugs against some clinical multidrug-resistant (MDR) M. tuberculosis strains. The gene expression profile of M. tuberculosis H37Rv after treatment with 4-deoxybostrycin was compared with untreated bacteria. One hundred and nineteen out of 3,875 genes were significantly different in M. tuberculosis exposed to 4-deoxybostrycin from control. There were 46 functionally known genes which are involved in metabolism, information storage and processing and cellular processes. The differential expressions of six genes were further confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). The present study provides a useful experiment basis for exploitation of correlative new drugs against TB and for finding out new targets of anti-mycobacterial therapy.

Innovative phytosynthesized silver nanoarchitectures with enhanced antifungal and antioxidant properties

NASA Astrophysics Data System (ADS)

Ortan, Alina; Fierascu, Irina; Ungureanu, Camelia; Fierascu, Radu Claudiu; Avramescu, Sorin Marius; Dumitrescu, Ovidiu; Dinu-Pirvu, Cristina Elena

2015-12-01

While in the early era of nanotechnology, nanoparticles of noble metals were obtained through expensive methods, using toxic chemical reagents, in the last decade attempts are made to obtain the desired chemical composition, size, morphology, and other properties by eco and green synthesis, using plants. The aim of this paper is to compare two extraction methods (hydroalcoholic extraction and microwave extraction) used to phytosynthesize silver nanoparticles, in terms of nanoparticle (NP) morphology, antioxidant, and antifungal action, using an European native plant, Anthriscus cerefolium (L.) Hoffm. The extracts and the obtained NPs were characterized by modern analytical techniques (GC-MS, UV-Vis, SEM, TEM) and by phytochemical assays (total flavonoids, total terpenoids and total phenolic content). The antifungal activity (evaluated using the Kirby-Bauer method, against Aspergillus niger and Penicillium hirsutum) and the antioxidant activity (determined by the DPPH assay and a chemiluminescence assay) revealed notable differences between the samples, differences due to the extraction procedure followed. Also, preliminary studies regarding the stability and the toxicity of the nanoparticles are presented. By using the microwave-assisted extraction, not only smaller particles (less than 10 nm) were obtained, but also with better antifungal and antioxidant properties than the ones obtained by classical extraction.

Metric adjusted skew information

PubMed Central

Hansen, Frank

2008-01-01

We extend the concept of Wigner–Yanase–Dyson skew information to something we call “metric adjusted skew information” (of a state with respect to a conserved observable). This “skew information” is intended to be a non-negative quantity bounded by the variance (of an observable in a state) that vanishes for observables commuting with the state. We show that the skew information is a convex function on the manifold of states. It also satisfies other requirements, proposed by Wigner and Yanase, for an effective measure-of-information content of a state relative to a conserved observable. We establish a connection between the geometrical formulation of quantum statistics as proposed by Chentsov and Morozova and measures of quantum information as introduced by Wigner and Yanase and extended in this article. We show that the set of normalized Morozova–Chentsov functions describing the possible quantum statistics is a Bauer simplex and determine its extreme points. We determine a particularly simple skew information, the “λ-skew information,” parametrized by a λ ∈ (0, 1], and show that the convex cone this family generates coincides with the set of all metric adjusted skew informations. PMID:18635683

Green synthesis of copper nanoparticles by Citrus medica Linn. (Idilimbu) juice and its antimicrobial activity.

PubMed

Shende, Sudhir; Ingle, Avinash P; Gade, Aniket; Rai, Mahendra

2015-06-01

We report an eco-friendly method for the synthesis of copper nanoparticles (CuNPs) using Citron juice (Citrus medica Linn.), which is nontoxic and cheap. The biogenic copper nanoparticles were characterized by UV-Vis spectrophotometer showing a typical resonance (SPR) at about 631 nm which is specific for CuNPs. Nanoparticles tracking analysis by NanoSight-LM20 showed the particles in the range of 10-60 nm with the concentration of 2.18 × 10(8) particles per ml. X-ray diffraction revealed the FCC nature of nanoparticles with an average size of 20 nm. The antimicrobial activity of CuNPs was determined by Kirby-Bauer disk diffusion method against some selected species of bacteria and plant pathogenic fungi. It was reported that the synthesized CuNPs demonstrated a significant inhibitory activity against Escherichia coli followed by Klebsiella pneumoniae, Pseudomonas aeruginosa, Propionibacterium acnes and Salmonella typhi. Among the plant pathogenic fungi tested, Fusarium culmorum was found to be most sensitive followed by F. oxysporum and F. graminearum. The novelty of this work is that for the first time citron juice was used for the synthesis of CuNPs.

Evidence for Anti-Pseudogymnoascus destructans (Pd) Activity of Propolis.

PubMed

Ghosh, Soumya; McArthur, Robyn; Guo, Zhi Chao; McKerchar, Rory; Donkor, Kingsley; Xu, Jianping; Cheeptham, Naowarat

2017-12-21

White-nose syndrome (WNS) in bats, caused by Pseudogymnoascus destructans ( Pd ), is a cutaneous infection that has devastated North American bat populations since 2007. At present, there is no effective method for controlling this disease. Here, we evaluated the effect of propolis against Pd in vitro. Using Sabouraud dextrose agar (SDA) medium, approximately 1.7 × 10⁷ conidia spores of the Pd strain M3906-2/mL were spread on each plate and grown to form a consistent lawn. A Kirby-Bauer disk diffusion assay was employed using different concentrations of propolis (1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%), in plates incubated at 8 °C and 15 °C. At 8 °C and 15 °C, as the concentration of propolis increased, there was an increasing zone of inhibition (ZOI), reaching the highest degree at 10% and 25% concentrations, respectively. A germule suppression assay showed a similar effect on Pd conidia germination. A MALDI-TOF-MS analysis of propolis revealed multiple constituents with a potential anti- Pd activity, including cinnamic acid, p-coumaric acid, and dihydrochalcones, which could be further tested for their individual effects. Our study suggests that propolis or its individual constituents might be suitable products against Pd .

Characterization of culturable bacteria isolated from the cold-water coral Lophelia pertusa

USGS Publications Warehouse

Galkiewicz, Julia P.; Pratte, Zoe A.; Gray, Michael A.; Kellogg, Christina A.

2011-01-01

Microorganisms associated with corals are hypothesized to contribute to the function of the host animal by cycling nutrients, breaking down carbon sources, fixing nitrogen, and producing antibiotics. This is the first study to culture and characterize bacteria from Lophelia pertusa, a cold-water coral found in the deep sea, in an effort to understand the roles that the microorganisms play in the coral microbial community. Two sites in the northern Gulf of Mexico were sampled over 2 years. Bacteria were cultured from coral tissue, skeleton, and mucus, identified by 16S rRNA genes, and subjected to biochemical testing. Most isolates were members of the Gammaproteobacteria, although there was one isolate each from the Betaproteobacteria and Actinobacteria. Phylogenetic results showed that both sampling sites shared closely related isolates (e.g. Pseudoalteromonas spp.), indicating possible temporally and geographically stable bacterial-coral associations. The Kirby-Bauer antibiotic susceptibility test was used to separate bacteria to the strain level, with the results showing that isolates that were phylogenetically tightly grouped had varying responses to antibiotics. These results support the conclusion that phylogenetic placement cannot predict strain-level differences and further highlight the need for culture-based experiments to supplement culture-independent studies.

Ultraviolet radiation and the snow alga Chlamydomonas nivalis (Bauer) Wille.

PubMed

Gorton, Holly L; Vogelmann, Thomas C

2003-06-01

Aplanospores of Chlamydomonas nivalis are frequently found in high-altitude, persistent snowfields where they are photosynthetically active despite cold temperatures and high levels of visible and ultraviolet (UV) radiation. The goals of this work were to characterize the UV environment of the cells in the snow and to investigate the existence and localization of screening compounds that might prevent UV damage. UV irradiance decreased precipitously in snow, with UV radiation of wavelengths 280-315 nm and UV radiation of wavelengths 315-400 nm dropping to 50% of incident levels in the top 1 and 2 cm, respectively. Isolated cell walls exhibited UV absorbance, possibly by sporopollenin, but this absorbance was weak in images of broken or plasmolyzed cells observed through a UV microscope. The cells also contained UV-absorbing cytoplasmic compounds, with the extrachloroplastic carotenoid astaxanthin providing most of the screening. Additional screening compound(s) soluble in aqueous methanol with an absorption maximum at 335 nm played a minor role. Thus, cells are protected against potentially high levels of UV radiation by the snow itself when they live several centimeters beneath the surface, and they rely on cellular screening compounds, chiefly astaxanthin, when located near the surface where UV fluxes are high.

The z = 1.6748 C I Absorber Toward the QSO PKS 1756+237

NASA Astrophysics Data System (ADS)

Roth, Katherine C.; Bauer, James M.; Jim, Kevin T. C.

We have detected C I ground-state absorption at zabs = 1.6748 toward the QSO PKS 1756+237 (zem = 1.725), making this only the fourth known C I QSO absorber. The absence of excited-state fine-structure C I lines is compatible with the redshifted Cosmic Microwave Background Radiation at an expected temperature of TCMBR (1+z) = 7.291 K (Mather et al. 1994, ApJ, 354, L37). We find a 2 σ upper-limit on the C I excitation temperature of Tex <= 7.73(+0.53, -0.46) K (Roth & Bauer 1999, ApJ, submitted). Our Keck HIRES spectra (8.3 km s-1 FWHM) obtained in May 1997 also reveal the existence of Ni II and Fe II lines with a sub-solar Ni/Fe abundance ratio, presumably indicative of dust. We have obtained deep, high resolution (0.3'' FWHM) images in H+K' with the UH 2.2m Tip-Tilt system of the QSO field in order to identify the system responsible for the zabs = 1.6748 absorption. We detect two faint candidate systems within 1.5'' and 3'' (≅ 15 and 30 kpc, Hcirc = 65) of the QSO.

[Change in drug resistance of Staphylococcus aureus].

PubMed

Lin, Yan; Liu, Yan; Luo, Yan-Ping; Liu, Chang-Ting

2013-11-01

To analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines. SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P < 0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

Infrared and Raman studies of hydrogen bonded complexes involving acetone, acetophenone and benzophenone—I. Thermodynamic constants and frequency shifts of the ν OH and ν CO stretching vibrations

NASA Astrophysics Data System (ADS)

Thijs, R.; Zeegers-Huyskens, Th.

The hydrogen bonded complexes between phenol derivatives and acetone ( I), acetophenone ( II) and benzophenone ( III) have been studied in carbon tetrachloride solution by i.r. spectroscopy. The formation constants, the enthalpies of complex formation, the Δν OH and Δν CO values have been determined. For a given phenol derivative, the thermodynamic constants and Δν OH are ordered according to I > II > III and the influence of a substituent implanted on the phenolic ring can be expressed by the Hammett relationship. The ϱ coefficients of the Hammett equation are related to the complexation enthalpies. The Badger—Bauer relation is valid for the three bases. The comparison with complexes involving other carbonyl bases allows to precise the influence of the substituent implanted on the carbonyl group. The Δν OH values obey the dual substituent parameter equation using σ I and σ +R; the ϱ I/ϱ R ratio is higher than one. The Δν CO values are shown to depend on the complexation enthalpy and on the delocalization effect of the substituents.

Extended 60 μm Emission from Nearby Mira Variables

NASA Astrophysics Data System (ADS)

Bauer, W. H.; Stencel, R. E.

1993-01-01

Circumstellar dust envelopes around some optically visible late-type stars are so extensive that they are detectable as extended at an arc-minute scale by the IRAS survey observations (Stencel, Pesce and Bauer 1988, Astron. J 95, 141; Hawkins 1990, Astron. Ap. 229, L8). The width of the IRAS scan profiles at 10% of peak intensity is an indicator of source extension. Wyatt and Cahn (1983, Ap. J. 275, 225) presented a sample of 124 Mira variables in the solar neighborhood. Of this sample, 11 Miras which show silicate emission are bright enough at 60 microns for a significant determination of the width of a scan at 10% of peak flux. Individual scans and maps were examined in order to determine whether any observed extension was associated with the central star. Five stars showed significant extension apparently due to mass loss from the central star: R Leo, o Cet, U Ori, R Cas and R Hor. IRAS LRS spectra, point source fluxes and observed extensions of these sources are compared to the predictions of model dust shells which assume steady mass loss. This work was supported in part by NASA grant NAG 5-1213 to Wellesley College.

Sinkhole progression at the Weeks Island, Louisiana, Strategic Petroleum Reserve (SPR) site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neal, J.T.; Bauer, S.J.; Ehgartner, B.L.

1995-11-01

A sinkhole measuring 11 m (36 ft) across and 9 m (30 ft) deep was first observed in alluvium overlying the Weeks Island, Louisiana, salt dome in May 1992, but it was about a year old, based on initial surface appearance and subsequent reverse extrapolation of growth rates. A second and much smaller sinkhole was identified in early 1995, nearly three years later. Their position directly over the edges of the SPR oil storage chamber, a former room-and-pillar salt mine, caused apprehension. The association of sinkholes over mines is well established and this occurrence suggested that groundwater influx undoubtedly wasmore » causing salt dissolution at shallow depth, and associated collapse of soil at the surface. Leaks of groundwater into other salt mines in Louisiana and elsewhere led to flooding and eventual abandonment (Coates et al., 1981). Consequently, much attention has been and continues to be given to characterizing these sinkholes, and to mitigation. This paper summarizes current engineering geologic concepts, and briefly describes diagnostic and risk mitigation efforts being conducted by the US Department of Energy, operator of the Strategic Petroleum Reserve (Bauer et al., 1994).« less

Comments on the possibility of cavitation in liquid metal targets for pulsed spallation neutron sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carpenter J.M.

When short pulses of protons strike the volume of a liquid target, the rapid heating produces a pressurized region which relaxes as the pressure wave propagates outward. Skala and Bauer have modeled the effects of the pressure wave impinging on the container walls of a liquid mercury target under ESS conditions. They find that high pressures and high wall stresses result if the medium is uniform, nearly incompressible liquid. The pressure and the stresses are much reduced if the liquid contains bubbles of helium, due to their high compressibility. However, according to the calculation, the pressure still reaches an atmospheremore » or so at the surface, which reflects the compressive wave as a rarefaction wave of the same magnitude. Even such modest underpressures can lead to the growth of bubbles (cavitation) at or near the surface, which can collapse violently and erode the container surface. It is necessary to avoid this. Leighton provides a wide ranging discussion of pressure waves in bubbly media, which may provide insights into the nature and control of cavitation phenomena. The paper surveys some of the relevant information from that source.« less

Bacterial meningitis in children under 15 years of age in Nepal.

PubMed

Shrestha, Rajani Ghaju; Tandukar, Sarmila; Ansari, Shamshul; Subedi, Akriti; Shrestha, Anisha; Poudel, Rekha; Adhikari, Nabaraj; Basnyat, Shital Raj; Sherchand, Jeevan Bahadur

2015-08-19

Bacterial meningitis in children is a life-threatening problem resulting in severe morbidity and mortality. For the prompt initiation of antibacterial therapy, rapid and reliable diagnostic methods are of utmost importance. Therefore, this study was designed to find out the rate of bacterial pathogens of meningitis from suspected cases by performing conventional methods and latex agglutination. A descriptive type of study was carried out from May 2012 to April 2013. Cerebrospinal fluid (CSF) specimens from 252 suspected cases of meningitis were subjected for Gram staining, bacterial culture and latex agglutination test. The identification of growth of bacteria was done following standard microbiological methods recommended by American Society for Microbiology. Antibiotic sensitivity testing was done by modified Kirby-Bauer disk diffusion method. From the total 252 suspected cases, 7.2 % bacterial meningitis was revealed by Gram staining and culture methods whereas latex agglutination method detected 5.6 %. Gram-negative organisms contributed the majority of the cases (72.2 %) with Haemophilus influenzae as the leading pathogen for meningitis. Overall, 33.3 % mortality rate was found. In conclusion, a significant rate of bacterial meningitis was found in this study prompting concern for national wide surveillance.

Carriage of Vibrio species by shrimps harvested from the coastal waters of South West Cameroon.

PubMed

Ndip, R N; Akoachere, J F T K; Mokosso, D K; Ndip, L M; Anyangwe, I A N

2002-03-01

To determine the prevalence of Vibrio spp in unprocessed shrimps and their susceptibility to antibiotics. A prospective study of Vibrio spp associated with shrimps harvested from the coastal waters of South West Cameroon. A laboratory based study at the Department of Life Sciences, University of Buea. Two hundred and thirty six shrimps harvested from the coastal towns of Limbe and Tiko, Cameroon, were examined for the prevalence of Vibrio spp using standard microbiologic procedures. The antibiotic sensitivity of isolates was determined using the Kirby-Bauer disc diffusion technique. Of the 236 shrimps examined, 73 (30.9%) were contaminated with Vibrio spp. Further, a total of 125 Vibrio strains were isolated from the contaminated shrimps. Of this number, 33 (26.4%) were V. cholerae, 55 (44%) V. parahaemolyticus, 34 (27.2%) V. alginolyticus and three (2.4%) V. vulnificus. Antibiotic susceptibility generally ranged from 68.8% for polymyxin B to 99.2% for gentamycin. Multiple resistant strains were noted, especially with V. parahaemolyticus and V. alginolyticus Shrimps maintain a reservoir of potential Vibrio spp in the coastal area of South West Cameroon. This finding is of epidemiologic and clinical significance.

A Sedimentary Carbon Inventory for a Scottish Sea Loch

NASA Astrophysics Data System (ADS)

Smeaton, Craig; Austin, William; Davies, Althea; Baltzer, Agnes

2015-04-01

Coastal oceans are sites of biogeochemical cycling, as terrestrial, atmospheric, and marine carbon cycles interact. Important processes that affect the carbon cycle in the coastal ocean include upwelling, river input, air-sea gas exchange, primary production, respiration, sediment burial, export, and sea-ice dynamics. The magnitude and variability of many carbon fluxes are accordingly much higher in coastal oceans than in open ocean environments. Having high-quality observations of carbon stocks and fluxes in the coastal environment is important both for understanding coastal ocean carbon balance and for reconciling continent-scale carbon budgets. Despite the ecological, biological, and economic importance of coastal oceans, the magnitude and variability of many of the coastal carbon stocks are poorly quantified in most regions in comparison to terrestrial and deep ocean carbon stocks. The first stage in understanding the carbon dynamics in coastal waters is to quantify the existing carbon stocks. The coastal sediment potentially holds a significant volume of carbon; yet there has been no comprehensive attempt to quantitatively determine the volume of carbon held in those coastal sediments as echoed by Bauer et al., (2013) "the diverse sources and sinks of carbon and their complex interactions in these waters remain poorly understood". We set out to create the first sedimentary carbon inventory for a sea loch (fjord); through a combination of geophysics and biogeochemistry. Two key questions must be answered to achieve this goal; how much sediment is held within the loch and what percentage of that sediment carbon? The restrictive geomorphology of sea lochs (fjords) provides the perfect area to develop this methodology and answer these fundamental questions. Loch Sunart the longest of the Scottish sea lochs is our initial test site due to existing geophysical data being available for analysis. Here we discuss the development of the joint geophysics and biogeochemical methodology and how it was applied to Loch Sunart. The methodology was applied to seismic geophysics data collected in 2009 (Baltzer et al. 2010,) and data compiled through biogeochemical analysis of sediment cores collected from Loch Sunart. Through the combination of these datasets we have undertaken calculations to quantify the total sediment mass and the percentage of carbon contained in that sediment. Through this work we have created the first holistic sedimentary carbon inventory for a sea loch; which is the first step to tackling the larger questions around coastal carbon. Baltzer, A, Bates, R, Mokeddem, Z, Clet-Pellerin, M, Walter-Simonnet, A-V, Bonnot-Courtois, C and Austin, WEN 2010, Using seismic facies and pollen analyses to evaluate climatically driven change in a Scottish sea loch (fjord) over the last 20 ka, Geological Society, London, Special Publications, 344, (1), pp. 355-369. Bauer, JE, Cai, W-J, Raymond, P a, Bianchi, TS, Hopkinson, CS and Regnier, P a G 2013, The changing carbon cycle of the coastal ocean., Nature, 504, (7478), pp. 61-70.

One year study of bacterial and fungal nosocomial infections among patients in pediatric intensive care unit (PICU) in Alexandria.

PubMed

El-Nawawy, Ahmed Ahmed; Abd El-Fattah, Mohamed Mohamed; Metwally, Hala Abd El-Raouf; Barakat, Shahira Salah El Din; Hassan, Ihab Abdel Rehim

2006-06-01

A 1-year prospective and observational study included all admissions (n=216) until 48 h after discharge to Alexandria PICU between first of May 2003 and end of April 2004. Cultures for bacteria and fungi and antibiotic sensitivity tests (19 antibiotic using Bauer-Kirby disc diffusion method) were obtained (blood, stool, urine and cerebrospinal fluid, if needed) and repeated on suspicion of NIs. All cannulae, endotracheal tube (ET) aspirates and tips, nasogastric tubes and different catheters were cultured. All PICU health care workers (HCWs) were subjected to throat and under-finger nails cultures as well as inanimate objects, both on bimonthly basis. The referral place (ward or emergency), PRISM III score, length of stay (LOS) and fate were recorded. Amongst those patients whose age ranged from 1 to 23 months, 23 per cent had NIs with infection rates of 40/1000 days. Significantly high rates of mortality, LOS and PRISM III score were encountered among patients with NIs (52 per cent vs 30 per cent; 9.4+/-4.8 vs 5.4+/-2.2 days; 14.4+/-7 vs 11.8+/-6 respectively). The descending order of frequency of NIs was blood stream infection (BSI) (47 per cent), urinary tract infection (UTI) (28 per cent), ventilator-associated pneumonia (VAP) (16 per cent) and meningitis (9 per cent). Gr-ve bacilli accounted for 76.7 per cent; Gr+ve cocci 13.3 per cent (with satisfactory sensitivity to cefepime, imipenem and meropenem) and Candida albicans 10 per cent of all NIs. The rate of NIs/1000 device days were: 18.7 per cent for BSI, 10.9 per cent for VAP and 25.5 per cent for UTI. Vulnerable age groups were >6 m for VAP and <6 m for meningitis. Multiple logistic regression analysis identified LOS, PRISM III score and referral from wards a predictors of NI acquisition (odd ratio and 95 per cent confidence interval: 1.537, 1.423-1.659; 1.073, 1.041-1.105 and 0.269, 0.178-0.406 respectively). Bimonthly cultures for HCWs isolated coagulase-ve Staphylococci, while inanimate objects isolated diphtheroids and Candida albicans. NIs rate was high (23 per cent) mainly due to severity of condition on admission as shown by high PRISM III score value, the high PRISM III score, LOS and referral from wards were predictors of acquisition of NIs and there is a high incidence of Candida albicans infection (10 per cent of NIs).

Development of carboxymethyl cellulose-based hydrogel and nanosilver composite as antimicrobial agents for UTI pathogens.

PubMed

Alshehri, Saad M; Aldalbahi, Ali; Al-Hajji, Abdullah Baker; Chaudhary, Anis Ahmad; Panhuis, Marc In Het; Alhokbany, Norah; Ahamad, Tansir

2016-03-15

Silver nanoparticles (AgNPs) containing hydrogel composite were first synthesized by preparing a new hydrogel from carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), and the cross-linker ethylene glycol diglycidyl ether (EGDE), followed by the incorporation of AgNPs by microwave radiation. The resulting neat hydrogels and AgNPs-hydrogel composites were characterized using spectral, thermal, microscopic analysis and X-ray diffraction (XRD) analyses. The SEM and TEM results demonstrated that the synthesized AgNPs were spherical with diameters ranging from 8 to 14nm. In addition, the XRD analysis confirmed the nanocrystalline phase of silver with face-centered cubic (FCC) crystal structure. Energy dispersive spectroscopy (EDS) analysis of the AgNPs confirmed the presence of an elemental silver signal, and no peaks of any other impurities were detected. Additionally, the antibacterial activities of the neat hydrogel and AgNPs-hydrogel composites were measured by Kirby-Bauer method against urinary tract infection (UTI) pathogens. The rheology measurement revealed that the values of storage modulus (G') were higher than that of loss modulus (G″). The AgNPs-hydrogel composites exhibited higher antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris, Staphylococcus aureus and Proteus mirabilis compared to the corresponding neat hydrogel. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antimicrobial activity of jasmine oil against oral microorganisms

NASA Astrophysics Data System (ADS)

Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

2018-02-01

Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

Evaluation of antioxidant, antibacterial, and antidiabetic potential of two traditional medicinal plants of India: Swertia cordata and Swertia chirayita.

PubMed

Roy, Priyanka; Abdulsalam, Fatima I; Pandey, D K; Bhattacharjee, Aniruddha; Eruvaram, Naveen Reddy; Malik, Tabarak

2015-06-01

Swertia cordata and Swertia chirayita are temperate Himalayan medicinal plants used as potent herbal drugs in Indian traditional systems of medicine (Ayurvedic, Unani and Siddha). Assessment of Antioxidant, antibacterial, and antidiabetic potential of Swertia cordata and Swertia chirayita. Phytochemicals of methanolic and aqueous extracts of the two Swertia species were analyzed. The antioxidant potential of all the extracts was assessed by measuring total phenolic content, total flavonoid content and free radical scavenging potential was assessed by 1,1-diphenyl-2-picrilhydrazyl (DPPH) assay, antibacterial activity was assessed against various pathogenic and nonpathogenic bacteria in vitro by Kirby-Bauer agar well diffusion method and antidiabetic activity was assessed by α-amylase inhibition. Methanolic leaf extracts of both the species of Swertia contain significant antibacterial as well as anti-diabetic potential, whereas methanolic root extracts of both species were found to have potential antioxidant activity. However, Swertia chirayita showed better activities than Swertia cordata although both species have good reputation in traditional Indian medicine. Both the species are having high medicinal potential in terms of their antioxidant, antibacterial and antidiabetic activities. Studies are required to further elucidate antioxidant, anti-diabetic and antibacterial potentials using various in-vitro, in-vivo biochemical and molecular biology techniques.

Evaluation of antioxidant, antibacterial, and antidiabetic potential of two traditional medicinal plants of India: Swertia cordata and Swertia chirayita

PubMed Central

Roy, Priyanka; Abdulsalam, Fatima I.; Pandey, D. K.; Bhattacharjee, Aniruddha; Eruvaram, Naveen Reddy; Malik, Tabarak

2015-01-01

Background: Swertia cordata and Swertia chirayita are temperate Himalayan medicinal plants used as potent herbal drugs in Indian traditional systems of medicine (Ayurvedic, Unani and Siddha). Objective: Assessment of Antioxidant, antibacterial, and antidiabetic potential of Swertia cordata and Swertia chirayita. Materials and Methods: Phytochemicals of methanolic and aqueous extracts of the two Swertia species were analyzed. The antioxidant potential of all the extracts was assessed by measuring total phenolic content, total flavonoid content and free radical scavenging potential was assessed by 1,1-diphenyl-2-picrilhydrazyl (DPPH) assay, antibacterial activity was assessed against various pathogenic and nonpathogenic bacteria in vitro by Kirby-Bauer agar well diffusion method and antidiabetic activity was assessed by α-amylase inhibition. Results: Methanolic leaf extracts of both the species of Swertia contain significant antibacterial as well as anti-diabetic potential, whereas methanolic root extracts of both species were found to have potential antioxidant activity. However, Swertia chirayita showed better activities than Swertia cordata although both species have good reputation in traditional Indian medicine. Conclusion: Both the species are having high medicinal potential in terms of their antioxidant, antibacterial and antidiabetic activities. Studies are required to further elucidate antioxidant, anti-diabetic and antibacterial potentials using various in-vitro, in-vivo biochemical and molecular biology techniques. PMID:26109789

Bacterial Etiology and Antibiotic Resistance Profile of Community-Acquired Urinary Tract Infections in a Cameroonian City.

PubMed

Nzalie, Rolf Nyah-Tuku; Gonsu, Hortense Kamga; Koulla-Shiro, Sinata

2016-01-01

Introduction. Community-acquired urinary tract infections (CAUTIs) are usually treated empirically. Geographical variations in etiologic agents and their antibiotic sensitivity patterns are common. Knowledge of antibiotic resistance trends is important for improving evidence-based recommendations for empirical treatment of UTIs. Our aim was to determine the major bacterial etiologies of CAUTIs and their antibiotic resistance patterns in a cosmopolitan area of Cameroon for comparison with prescription practices of local physicians. Methods. We performed a cross-sectional descriptive study at two main hospitals in Yaoundé, collecting a clean-catch mid-stream urine sample from 92 patients having a clinical diagnosis of UTI. The empirical antibiotherapy was noted, and identification of bacterial species was done on CLED agar; antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Results. A total of 55 patients had samples positive for a UTI. Ciprofloxacin and amoxicillin/clavulanic acid were the most empirically prescribed antibiotics (30.9% and 23.6%, resp.); bacterial isolates showed high prevalence of resistance to both compounds. Escherichia coli (50.9%) was the most common pathogen, followed by Klebsiella pneumoniae (16.4%). Prevalence of resistance for ciprofloxacin was higher compared to newer quinolones. Conclusions. E. coli and K. pneumoniae were the predominant bacterial etiologies; the prevalence of resistance to commonly prescribed antibiotics was high.

Electrostatics of proteins in dielectric solvent continua. II. Hamiltonian reaction field dynamics

NASA Astrophysics Data System (ADS)

Bauer, Sebastian; Tavan, Paul; Mathias, Gerald

2014-03-01

In Paper I of this work [S. Bauer, G. Mathias, and P. Tavan, J. Chem. Phys. 140, 104102 (2014)] we have presented a reaction field (RF) method, which accurately solves the Poisson equation for proteins embedded in dielectric solvent continua at a computational effort comparable to that of polarizable molecular mechanics (MM) force fields. Building upon these results, here we suggest a method for linearly scaling Hamiltonian RF/MM molecular dynamics (MD) simulations, which we call "Hamiltonian dielectric solvent" (HADES). First, we derive analytical expressions for the RF forces acting on the solute atoms. These forces properly account for all those conditions, which have to be self-consistently fulfilled by RF quantities introduced in Paper I. Next we provide details on the implementation, i.e., we show how our RF approach is combined with a fast multipole method and how the self-consistency iterations are accelerated by the use of the so-called direct inversion in the iterative subspace. Finally we demonstrate that the method and its implementation enable Hamiltonian, i.e., energy and momentum conserving HADES-MD, and compare in a sample application on Ac-Ala-NHMe the HADES-MD free energy landscape at 300 K with that obtained in Paper I by scanning of configurations and with one obtained from an explicit solvent simulation.

How Kondo-holes create intense nanoscale heavy-fermion hybridization disorder

PubMed Central

Hamidian, Mohammad H.; Schmidt, Andrew R.; Firmo, Inês A.; Allan, Milan P.; Bradley, Phelim; Garrett, Jim D.; Williams, Travis J.; Luke, Graeme M.; Dubi, Yonatan; Balatsky, Alexander V.; Davis, J. C.

2011-01-01

Replacing a magnetic atom by a spinless atom in a heavy-fermion compound generates a quantum state often referred to as a “Kondo-hole”. No experimental imaging has been achieved of the atomic-scale electronic structure of a Kondo-hole, or of their destructive impact [Lawrence JM, et al. (1996) Phys Rev B 53:12559–12562] [Bauer ED, et al. (2011) Proc Natl Acad Sci. 108:6857–6861] on the hybridization process between conduction and localized electrons which generates the heavy-fermion state. Here we report visualization of the electronic structure at Kondo-holes created by substituting spinless thorium atoms for magnetic uranium atoms in the heavy-fermion system URu2Si2. At each thorium atom, an electronic bound state is observed. Moreover, surrounding each thorium atom we find the unusual modulations of hybridization strength recently predicted to occur at Kondo-holes [Figgins J, Morr DK (2011) Phys Rev Lett 107:066401]. Then, by introducing the “hybridization gapmap” technique to heavy-fermion studies, we discover intense nanoscale heterogeneity of hybridization due to a combination of the randomness of Kondo-hole sites and the long-range nature of the hybridization oscillations. These observations provide direct insight into both the microscopic processes of heavy-fermion forming hybridization and the macroscopic effects of Kondo-hole doping. PMID:22006302

Detection of resistance to linezolid in Staphylococcus aureus infecting orthopedic patients.

PubMed

Thool, Vaishali U; Bhoosreddy, Girish L; Wadher, Bharat J

2012-01-01

In today's medical scenario, the human race is battling the most intelligent enemy who has unending alternatives to combat with the potent elements they have produced against it. To study the resistance to linezolid among Staphylococcus aureus isolated from pus samples of orthopedic patients. Pus samples were collected from dirty wounds of orthopedic patients undergoing long antimicrobial treatment programs. The sampling period was from July 2010 to June 2011. The samples were collected from different orthopedic hospitals of Nagpur (central India) representing a mixed sample of patients. One hundred pus samples were screened for S. aureus, by growth on mannitol salt agar (MSA), Baird-Parker agar (BPA), deoxyribonuclease test, tube coagulase test, and HiStaph latex agglutination test. Fifty-one S. aureus isolates were obtained which were further subjected to antimicrobial susceptibility testing by Kirby-Bauer disc diffusion method (DDM). Minimal inhibitory concentrations (MICs) were determined by an automated system, the VITEK 2 system. Also, Ezy MIC strip method was carried out in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Twelve linezolid-resistant S. aureus (LRSA) isolates were recovered from 51 S. aureus cultures tested for susceptibility to linezolid using the DDM, VITEK 2 system, and Ezy MIC strip method. The emergence of resistance suggests nosocomial spread and abuse of antibiotic.

Effects of bovine milk lactoperoxidase system on some bacteria.

PubMed

Cankaya, M; Sişecioğlu, M; Bariş, O; Güllüce, M; Ozdemir, H

2010-01-01

Bovine lactoperoxidase (LPO) was purified from skimmed milk using amberlite CG-50-H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography. Lactoperoxidase was purified 20.45-fold with a yield of 28.8%. Purity of enzyme checked by sodium dodecyl sulphate-polyacrylamide gel electrophoresis method and a single band was observed. Km was 0.25 mM at 20 degrees C, Vmax value was 7.95 micromol/ml min at 20 degrees C (pH 6.0). Antibacterial study was done by disk diffusion method of Kir-by-Bauer using Mueller-Hinton agar medium with slight modification. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate-100 mM H2O2 medium for some bacteria (Brevibacillus centrosaurus, B. choshinensis, B. lyticum, Cedecea davisae, Chryseobacterium indoltheticum, Clavibacter michiganense pv. insidiosum, Kocuria erythromyxa, K. kristinae, K. rosea, K. varians, Paenibacillus validus, Pseudomonas syringae pv. populans, Ralstonia pickettii, Rhodococcus wratislaviensis, Serratia fonticola, Streptomyces violaceusniger, Vibrio cholerae-nonO1) respectively, and compared with well known antibacterial substances (levofloxacin, netilmicin). LPO system has inhibition effects on all type bacteria and concentration is really important such as LPO-100 mM thiocyanate-100 mM H2O2 system was proposed as an effective agent against many factors causing several diseases.

Synthesis, spectroscopic, anticancer, antibacterial and antifungal studies of Ni(II) and Cu(II) complexes with hydrazine carboxamide, 2-[3-methyl-2-thienyl methylene

NASA Astrophysics Data System (ADS)

Chandra, Sulekh; Vandana; Kumar, Suresh

2015-01-01

Schiff's base ligand(L) hydrazine carboxamide, 2-[3-methyl-2-thienyl methylene] and its metal complexes have been synthesized and characterized by elemental analysis, molar conductance, various spectroscopic techniques such as electronic, IR, 1H NMR, mass, EPR. Molar conductance of complexes in DMF solution corresponds to non-electrolyte. Complexes have general composition [M(L)2X2], where M = Ni(II) and Cu(II), X = Cl-, NO3-, CH3COO- and ½SO42-. On the basis of above spectral studies, an octahedral geometry has been assigned for Ni(II) complexes and tetragonal geometry for Cu(II) complexes except [Cu(L)2SO4] which possesses five coordinated trigonal bipyramidal geometry. These metal complexes were also tested for their anticancer, antibacterial and antifungal activities to assess their inhibition potential. Anticancer activity of ligand and its metal complexes were evaluated using SRB fluorometric assay and Adriamycin (ADR) was applied as positive control. Schiff's base ligand and its metal complexes were screened for their antibacterial and antifungal activity against Escherichia coli, Bacillus cereus and Aspergillus niger, Aspergillus flavus, respectively. Kirby-Bauer single disk susceptibility test was used for antibacterial activity and well diffusion method for antifungal activity of the compounds on the used fungi.

Pharmacokinetic and pharmacodynamic evaluations of a 10 mg/kg enrofloxacin intramuscular administration in bearded dragons (Pogona vitticeps): a preliminary assessment.

PubMed

Salvadori, M; Vercelli, C; De Vito, V; Dezzutto, D; Bergagna, S; Re, G; Giorgi, M

2017-01-01

Enrofloxacin (E) is commonly used in veterinary medicine. It is necessary to perform pharmacokinetic/dynamic studies to minimize the selection of resistant mutants of bacteria and extend the efficacy of antimicrobial agents. Eight healthy adult Pogona vitticeps were assigned into two groups of equal size and treated with a single intramuscular injection of E at 10 mg/kg. Blood samples were withdrawn at different scheduled times for each group, and rectal swabs were collected. E and ciprofloxacin (active metabolite) blood concentrations were quantified by an HPLC validated method, while the in vitro antimicrobial susceptibility was evaluated by the Kirby-Bauer disc diffusion susceptibility test. The pharmacokinetic profiles of E gave similar pharmacokinetic parameters irrespective of the collection time schedule. Bacteria isolation showed the presence of both E. coli, Salmonella enterica subspecies enterica and subspecies 3a, Proteus spp., and Pseudomonas spp. The majority of isolated colonies were sensitive to E, but the treatment did not reduce the number of bacteria in faeces. Results suggest that E is able to reach blood concentrations high enough to kill susceptible bacteria (MIC < 0.9 μg/mL), but at the same time does not significantly affect intestinal bacteria. © 2016 John Wiley & Sons Ltd.

The light environment and cellular optics of the snow alga Chlamydomonas nivalis (Bauer) Wille.

PubMed

Gorton, H L; Williams, W E; Vogelmann, T C

2001-06-01

The alga Chlamydomonas nivalis lives in a high-light, cold environment: persistent alpine snowfields. Since the algae in snow receive light from all angles, the photon fluence rate is the critical parameter for photosynthesis, but it is rarely measured. We measured photon irradiance and photon fluence rate in the snow that contained blooms of C. nivalis. On a cloudless day the photon fluence rate at the snow surface was nearly twice the photon irradiance, and it can be many times greater than the photon irradiance when the solar angle is low or the light is diffuse. Beneath the surface the photon fluence rate can be five times the photon irradiance. Photon irradiance and photon fluence rate declined exponentially with depth, approximating the Bouguer-Lambert relationship. We used an integrating sphere to measure the spectral characteristics of a monolayer of cells and microscopic techniques to examine the spectral characteristics of individual cells. Astaxanthin blocked blue light and unknown absorbers blocked UV radiation; the penetration of these wavelengths through whole cells was negligible. We extracted astaxanthin, measured absorbance on a per-cell basis and estimated that the layer of astaxanthin within cells would allow only a small percentage of the blue light to reach the chloroplast, potentially protecting the chloroplast from excessive light.

Efficient synthesis of PMMA@Co0.5Ni0.5Fe2O4 organic-inorganic hybrids containing hyamine 1622 - Physicochemical properties, cytotoxic assessment and antimicrobial activity.

PubMed

Zachanowicz, E; Pigłowski, J; Grzymajło, M; Poźniak, B; Tikhomirov, M; Pierunek, N; Śniadecki, Z; Idzikowski, B; Marycz, K; Marędziak, M; Kisała, J; Hęclik, K; Pązik, R

2018-09-01

The PMMA@Co 0.5 Ni 0.5 Fe 2 O 4 ferrite containing hybrid nanomaterials with hyamine were prepared using emulsion polymerization method. Structural and morphological properties were evaluated using XRD, FT-IR, SEM techniques. The TGA and DTA analysis were performed in order to study the thermal properties of hybrid materials in contrast to reference material. Magnetic properties were studied using Quantum Design PPMS (VSM option) in a constant external magnetic field equal (100 Oe and 1000 Oe) in the temperature range from 2 to 380 K. Both the pure Co 0.5 Ni 0.5 Fe 2 O 4 and the sample with 85% of PMMA exhibit superparamagnetic behavior whereas blocking temperatureT B decreases with increase of PMMA content. The cytotoxicity assessment of PMMA@Co 0.5 Ni 0.5 Fe 2 O 4 with hyamine in J774.E murine macrophages and U2OS human osteosarcoma cell lines was performed. Additionally, sensitivity of bacteria Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923 to hybrid materials (with/without hyamine) was investigated using a of Kirby-Bauer disc method. Copyright © 2018. Published by Elsevier B.V.

Climatic factors and community - associated methicillin-resistant Staphylococcus aureus skin and soft-tissue infections - a time-series analysis study.

PubMed

Sahoo, Krushna Chandra; Sahoo, Soumyakanta; Marrone, Gaetano; Pathak, Ashish; Lundborg, Cecilia Stålsby; Tamhankar, Ashok J

2014-08-29

Skin and soft tissue infections caused by Staphylococcus aureus (SA-SSTIs) including methicillin-resistant Staphylococcus aureus (MRSA) have experienced a significant surge all over the world. Changing climatic factors are affecting the global burden of dermatological infections and there is a lack of information on the association between climatic factors and MRSA infections. Therefore, association of temperature and relative humidity (RH) with occurrence of SA-SSTIs (n = 387) and also MRSA (n = 251) was monitored for 18 months in the outpatient clinic at a tertiary care hospital located in Bhubaneswar, Odisha, India. The Kirby-Bauer disk diffusion method was used for antibiotic susceptibility testing. Time-series analysis was used to investigate the potential association of climatic factors (weekly averages of maximum temperature, minimum temperature and RH) with weekly incidence of SA-SSTIs and MRSA infections. The analysis showed that a combination of weekly average maximum temperature above 33 °C coinciding with weekly average RH ranging between 55% and 78%, is most favorable for the occurrence of SA-SSTIs and MRSA and within these parameters, each unit increase in occurrence of MRSA was associated with increase in weekly average maximum temperature of 1.7 °C (p = 0.044) and weekly average RH increase of 10% (p = 0.097).

Evidence for Anti-Pseudogymnoascus destructans (Pd) Activity of Propolis

PubMed Central

Ghosh, Soumya; McArthur, Robyn; Guo, Zhi Chao; McKerchar, Rory; Donkor, Kingsley

2017-01-01

White-nose syndrome (WNS) in bats, caused by Pseudogymnoascus destructans (Pd), is a cutaneous infection that has devastated North American bat populations since 2007. At present, there is no effective method for controlling this disease. Here, we evaluated the effect of propolis against Pd in vitro. Using Sabouraud dextrose agar (SDA) medium, approximately 1.7 × 107 conidia spores of the Pd strain M3906-2/mL were spread on each plate and grown to form a consistent lawn. A Kirby–Bauer disk diffusion assay was employed using different concentrations of propolis (1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%, 25%), in plates incubated at 8 °C and 15 °C. At 8 °C and 15 °C, as the concentration of propolis increased, there was an increasing zone of inhibition (ZOI), reaching the highest degree at 10% and 25% concentrations, respectively. A germule suppression assay showed a similar effect on Pd conidia germination. A MALDI-TOF-MS analysis of propolis revealed multiple constituents with a potential anti-Pd activity, including cinnamic acid, p-coumaric acid, and dihydrochalcones, which could be further tested for their individual effects. Our study suggests that propolis or its individual constituents might be suitable products against Pd. PMID:29267199

Comparative study of volatile oil content and antimicrobial activity of pecan cultivars growing in Egypt.

PubMed

El Hawary, Seham S; Zaghloul, Soumaya S; El Halawany, Ali M; El Bishbishy, Mahitab H

2013-11-01

The volatile oils obtained from the leaves of four pecan cultivars growing in Egypt were evaluated for their chemical composition and antimicrobial activity. The selected cultivars (cv.) were Carya illinoinensis (Wangneh.) K. Koch. cv. Wichita, C. illinoinensis cv. Western Schley, C. illinoinensis cv. Cherokee, and C. illinoinensis cv. Sioux. The gas chromatography-mass spectrometry analyses revealed that the volatile oils from samples of the different cultivars differ in composition and percentage of their components. β-Curcumene was found as the major constituent of the cv. Wichita oil, whereas germacrene D was the major component of cv. Sioux, cv. Cherokee, and cv. Western Schley. The antimicrobial activity was assayed using the Kirby-Bauer Method by measuring the zone of inhibition of growth. All volatile oils displayed an antimicrobial activity against the tested bacterial strains. On the other hand, only the volatile oil of cv. Wichita showed an antifungal effect on Aspergillus flavus. This work has identified candidates of volatile oils for future in vivo studies to develop antibiotic substitutes for the diminution of human and animal pathogenic bacteria. Nevertheless, the variations of the volatile oil components and antimicrobial potencies of the different studied cultivars, necessitate identifying the cultivars used in future studies.

Ergosterol, arabitol and manitol as tracers for biological aerosols

NASA Astrophysics Data System (ADS)

Rudich, Y.; Burshtein, N.; Lang-Yona, N.

2010-12-01

Airborne fungi can cause a wide array of adverse responses in humans depending on the type and quantity present. Since dose and human response is highly individual, the sensitivity of a person exposed is also an important consideration. The abundance of bioaerosols in the ambient air and their health impacts depend on the season and on the environmental conditions. In order to quantify and identify fungi bioaerosols’ contribution to atmospheric aerosols and the impact to public health, it has been suggested to use chemicals that are typical of bioaerosols as biomarkers in chemical analysis of collected aerosols. An often used biomarker for determining the fungal biomass is ergosterol. Recently, Bauer et al. (2008) found that mannitol and arabitol concentrations are correlated with the fungal spore counts in atmospheric PM10. In this study, ergosterol, arabitol and mannitol were quantified in ambient aerosols collected in the Eastern Mediterranean region for 12 months in order to understand their annual and seasonal behavior and to test whether arabitol and mannitol are good predictors of fungi. Finally, correlations between ergosterol abundances with inorganic ions, humidity, temperature, and synoptic data in order to identify dominant sources of fungal spores were also studied. We will report on the measurements and the observed correlations between the different tracers.

The State of Higher Education for STEM LGBTQQ Faculty/Staff

NASA Astrophysics Data System (ADS)

Rankin, Susan

2012-02-01

It has long been understood---an understanding that has been well supported by research-based evidence---that institutional ``climate'' has a profound effect on any academic community's ability to carry out its tripartite mission of teaching, research, and service (Bauer, 1996; Boyer, 1990; Peterson & Spencer, 1990; Rankin, 1998; 2003; 2010; Rankin & Reason, 2008; Tierney & Dilley, 1996). With the acknowledgment that institutions differ in the level of attention and emphasis on issues campus climate, it is safe to say that a campus climate offering equitable learning opportunities for all students, academic freedom for all faculty, and fairness in employment for all staff and administrators is one of the primary responsibilities of institutions of higher education. The research also suggests that a challenging campus climate exists for LGBTQQ students, faculty and staff. Based on the literature, a challenging climate leads to decreased productivity, decreased sense of value to the community, decreased retention, and negatively influences educational outcomes (Settles, et al. 2006; Trower & Chait (2002); Pascrell & Terenzini, 2005; Whitt, Edison, Pascarella, Terenzini, & Nora, 2001). Little is available in the literature on LGBTQQ faculty in the STEM fields. This program will engage participants in a review of the results of the 2010 project with regard to the experiences of LGBTQQ faculty and staff in the STEM fields.

Resonant nature of intrinsic defect energy levels in PbTe revealed by infrared photoreflectance spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Bingpo; Cai, Chunfeng; Jin, Shuqiang

2014-07-14

Step-scan Fourier-transform infrared photoreflectance and modulated photoluminescence spectroscopy were used to characterize the optical transitions of the epitaxial PbTe thin film grown by molecular beam epitaxy on BaF{sub 2} (111) substrate in the vicinity of energy gap of lead telluride at 77 K. It is found that the intrinsic defect energy levels in the electronic structure are of resonant nature. The Te-vacancy energy level is located above the conduction band minimum by 29.1 meV. Another defect (V{sub X}) energy level situated below valance band maximum by 18.1 meV is also revealed. Whether it is associated with the Pb vacancy is still not clear.more » It might also be related to the misfit dislocations stemming from the lattice mismatch between PbTe and BaF{sub 2} substrate. The experimental results support the theory prediction (N. J. Parada and G. W. Pratt, Jr., Phys. Rev. Lett. 22, 180 (1969), N. J. Parada, Phys. Rev. B 3, 2042 (1971)) and are consistent with the reported Hall experimental results (G. Bauer, H. Burkhard, H. Heinrich, and A. Lopez-Otero, J. Appl. Phys. 47, 1721 (1976)).« less

Diarrheagenic Escherichia coli Phylogroups Are Associated with Antibiotic Resistance and Duration of Diarrheal Episode

PubMed Central

Mosquito, Susan; Pons, Maria J.; Riveros, Maribel; Ochoa, Theresa J.

2015-01-01

Conventionally, in Escherichia coli, phylogenetic groups A and B1 are associated with commensal strains while B2 and D are associated with extraintestinal strains. The aim of this study was to evaluate diarrheagenic (DEC) and commensal E. coli phylogeny and its association with antibiotic resistance and clinical characteristics of the diarrheal episode. Phylogenetic groups and antibiotic resistance of 369 E. coli strains (commensal strains and DEC from children with or without diarrhea) isolated from Peruvian children <1 year of age were determined by a Clermont triplex PCR and Kirby-Bauer method, respectively. The distribution of the 369 E. coli strains among the 4 phylogenetic groups was A (40%), D (31%), B1 (21%), and B2 (8%). DEC-control strains were more associated with group A while DEC-diarrhea strains were more associated with group D (P < 0.05). There was a tendency (P = 0.06) for higher proportion of persistent diarrhea (≥14 days) among severe groups (B2 and D) in comparison with nonsevere groups (A and B1). Strains belonging to group D presented significantly higher percentages of multidrug resistance than the rest of the groups (P > 0.01). In summary, DEC-diarrhea strains were more associated with group D than strains from healthy controls. PMID:25811044

Biosynthesis of silver nanoparticles using Alternanthera sessilis (Linn.) extract and their antimicrobial, antioxidant activities.

PubMed

Niraimathi, K L; Sudha, V; Lavanya, R; Brindha, P

2013-02-01

The present work focuses the use of the aqueous extract of Alternanthera sessilis Linn. (Amaranthaceae) in producing silver nanoparticles (AgNPs) from silver nitrate aqueous. Phytochemical analysis of the extract revealed the presence of alkaloid, tannins, ascorbic acid, carbohydrates and proteins and they serve as effective reducing and capping agents for converting silver nitrate into nanoparticles. The synthesized silver nanoparticles (AgNPs) were also tested for proteins and ascorbic acid. Its pH was also determined (5.63). The AgNPs obtained was characterized by UV-vis spectroscopy, FT-IR spectroscopy, SEM, Zeta sizer and TG-DSC. SEM images which revealed the presence of various shapes and sizes. FT-IR spectrum showed the AgNPs having a coating of proteins indicating a dual role of bio-molecules responsible for capping and efficient stabilization of the silver nanoparticles. Presence of impurities and melting point profile were screened by TG-DSC analyzer. AgNPs were synthesized from the silver nitrate through the reducing power of ascorbic acid present in A. sessilis leaves. In this study, we also investigated antimicrobial and antioxidant activity of green synthesized AgNPs. The antimicrobial activity is investigated by Bauer et al.'s method. Antioxidant activity was done by DPPH method. Copyright © 2012 Elsevier B.V. All rights reserved.

Mechanical, material, and antimicrobial properties of acrylic bone cement impregnated with silver nanoparticles.

PubMed

Slane, Josh; Vivanco, Juan; Rose, Warren; Ploeg, Heidi-Lynn; Squire, Matthew

2015-03-01

Prosthetic joint infection is one of the most serious complications that can lead to failure of a total joint replacement. Recently, the rise of multidrug resistant bacteria has substantially reduced the efficacy of antibiotics that are typically incorporated into acrylic bone cement. Silver nanoparticles (AgNPs) are an attractive alternative to traditional antibiotics resulting from their broad-spectrum antimicrobial activity and low bacterial resistance. The purpose of this study, therefore, was to incorporate metallic silver nanoparticles into acrylic bone cement and quantify the effects on the cement's mechanical, material and antimicrobial properties. AgNPs at three loading ratios (0.25, 0.5, and 1.0% wt/wt) were incorporated into a commercial bone cement using a probe sonication technique. The resulting cements demonstrated mechanical and material properties that were not substantially different from the standard cement. Testing against Staphylococcus aureus and Staphylococcus epidermidis using Kirby-Bauer and time-kill assays demonstrated no antimicrobial activity against planktonic bacteria. In contrast, cements modified with AgNPs significantly reduced biofilm formation on the surface of the cement. These results indicate that AgNP-loaded cement is of high potential for use in primary arthroplasty where prevention of bacterial surface colonization is vital. Copyright © 2014 Elsevier B.V. All rights reserved.

Antimicrobial activity of tempeh gembus hydrolyzate

NASA Astrophysics Data System (ADS)

Noviana, A.; Dieny, F. F.; Rustanti, N.; Anjani, G.; Afifah, D. N.

2018-02-01

Tropical disease can be prevented by consumming fermented foods that have antimicrobial activity. One of them is tempeh gembus that has short shelf life. It can be overcome by processing it into hydrolyzate. This study aimed to determine antimicrobial activity of tempeh gembus hydrolyzate. Tempeh gembus was made of local soybean from Grobogan. They were added 5,000 ppm, 8,000 ppm, and 10,000 ppm of bromelain enzyme (TGH BE). Antimicrobial effects of TGH BE were tested against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Steptococcus mutans. Antimicrobial test was carried out using Kirby-Bauer Disc Diffussion method. Soluble protein test used Bradford method. The largest inhibition zone against S. aureus and S. mutans were shown by TGH BE 8,000 ppm, 0.89±0.53 mm and 2.40±0.72 mm. The largest inhibition zone of B. subtilis, 7.33±2,25 mm, was shown by TGH BE 5,000 ppm. There wasn’t antimicrobial effect of TGH BE against E. coli. There weren’t significant differences of soluble protein (P=0.293) and the inhibition zones againt S. aureus (P = 0.967), E. coli (P = 1.000), B. subtilis (P = 0.645), S. mutans (P=0.817) of all treatments. There were antimicrobial activities of TGH BE against S. aureus, B. subtilis, and S. mutans.

Natural versus Urban dunes along the Emilia-Romagna coast, Northern Adriatic (Italy)

NASA Astrophysics Data System (ADS)

Corbau, Corinne; Simeoni, Umberto

2014-05-01

Beach-dune interaction models can be precious tools for land managers and policymakers. However, if the models are inaccurate, land use policies may be designed based on false pretences or assumptions leading to poor land management, long-term erosion and sustainability issues, and increased difficulties in maintaining the dynamic coastal systems. From the literature, it appears that even the most reliable beach-dunes interactions models are not applicable to all coastal systems (Short and Hesp, 1982; Psuty, 1988; Sherman and Bauer, 1993). The study aims to identify the morphological evolution of the Emilia-Romagna coastal dunes according to its natural and "human" characteristics and to classify groups of dunes with similar evolutionary patterns. The coastal area consists essentially of 130 km of low sandy coast, interrupted by vast lagoon areas, harbor jetties and numerous hard coastal defense structures that were built during the first half of the 20th century to protect the Emilia-Romagna coast against erosion. Today about 57% of the littoral is protected by hard defenses, which have modified the morphodynamic characteristics of the beach without inverting the negative coastal evolution's trend. From recent aerial photographs (2011), 62 coastal dunes have been identified and mapped. Furthermore, the dune analysis shows a variability of the "physical characteristics" of coastal-dune systems along the Emilia-Romagna coast. The dune height varies from 1 to 7 meters, the width of the beach and of the active dunes range respectively from 10 to 150 m and from 10 to 65 m. Three main factors may explain the variability of the "physical characteristics": 1- Firstly the frontal dunes may be of different states according to the classification of Hesp (2002) since they correspond to incipient foredunes, well-developed foredunes, blowouts, residual foredunes as well as reactivated relict foredunes, 2- This could also be related to a different orientation of the coastline and foredune's line to the dominant onshore winds and, 3- Human impacts may also explain this variability since most of the dune-beach systems of Emilia-Romagna are characterized by important anthropogenic features that do not adequately describe beach-foredune interactions. A factor analysis of the coastal dunes has allowed formulating hypotheses about their evolutionary trends according to the importance and interference of factors, both natural and anthropic, acting on the beach-dune system. Four groups of dunes have been identified corresponding to natural dunes, semi-anthropic dunes with major natural features, semi-anthropic dunes with major anthropic feature and "urban" dunes. Furthermore, while human activities impede the formation and development of new incipient dunes, other human activities favor the conservation and development of the human-altered foredunes. Hesp, P., 2002: Foredunes and blowouts: initiation, geomorphology and dynamics, Geomorphology, 245-268. Psuty, N. P. 1988. Sediment budget and dune/beach interaction. Journal of Coastal Research Special Issue 3: 1-4. Sherman, D. J., and B. O. Bauer. 1993. Dynamics of beach-dune systems. Progress in Physical Geography 17 (4): 413-447 Short, A. D., and P. A. Hesp. 1982. Wave, beach and dune interactions in South Eastern Australia. Marine Geology 48: 259-284.

Sustainable antimicrobial effect of silver sulfadiazine-loaded nanosheets on infection in a mouse model of partial-thickness burn injury.

PubMed

Ito, Keisuke; Saito, Akihiro; Fujie, Toshinori; Nishiwaki, Keisuke; Miyazaki, Hiromi; Kinoshita, Manabu; Saitoh, Daizoh; Ohtsubo, Shinya; Takeoka, Shinji

2015-09-01

Partial-thickness burn injury has the potential for reepithelialization and heals within 3weeks. If the wound is infected by bacteria before reepithelization, however, the depth of disruption increases and the lesion easily progresses to the full-thickness dermal layers. In the treatment of partial-thickness burn injury, it is important to prevent the wound area from bacterial infection with an antimicrobial dressing. Here, we have tested the antimicrobial properties of polymeric ultra-thin films composed of poly(lactic acid) (termed "PLA nanosheets"), which have high flexibility, adhesive strength and transparency, and silver sulfadiazine (AgSD), which exhibits antimicrobial efficacy. The AgSD-loaded nanosheet released Ag(+) for more than 3days, and exerted antimicrobial efficacy against methicillin-resistant Staphylococcus aureus (MRSA) in an in vitro Kirby-Bauer test. By contrast, a cell viability assay indicated that the dose of AgSD used in the PLA nanosheets did not show significant cytotoxicity toward fibroblasts. In vivo evaluation using a mouse model of infection in a partial-thickness burn wound demonstrated that the nanosheet significantly reduced the number of MRSA bacteria on the lesion (more than 10(5)-fold) and suppressed the inflammatory reaction, thereby preventing a protracted wound healing process. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Coagulase-negative staphylococci from non-mastitic bovine mammary gland: characterization of Staphylococcus chromogenes and Staphylococcus haemolyticus by antibiotic susceptibility testing and pulsed-field gel electrophoresis.

PubMed

Pate, Mateja; Zdovc, Irena; Avberšek, Jana; Ocepek, Matjaž; Pengov, Andrej; Podpečan, Ožbalt

2012-05-01

During routine microbiological examination of milk samples from dairy cows without clinical signs of mastitis, quarter milk samples of 231 dairy cows from 12 herds were investigated for the presence of coagulase-negative staphylococci (CNS). The isolates were identified on the basis of colony morphology, Gram staining, catalase and coagulase test and the commercial kit, API Staph. CNS was detected in 29% (67/231) of the cows. A total of seven CNS species were identified with the most prevalent being Staphylococcus (Staph.) chromogenes (30%) and Staph. haemolyticus (28·8%), followed by Staph. simulans (11·2%), Staph. xylosus (11·2%), Staph. epidermidis (7·5%), Staph. hyicus (6·3%) and Staph. sciuri (5%). The predominant species, Staph. chromogenes and Staph. haemolyticus, were further characterized by antibiotic susceptibility testing using the agar disc diffusion method (Kirby-Bauer) and by pulsed-field gel electrophoresis (PFGE). Considerable resistance to ampicillin and penicillin was observed in both species. Isolates with identical or highly similar PFGE profiles were detected at the herd level despite a marked heterogeneity seen for both species. On the basis of somatic cell count, absence of clinical signs of inflammation and heterogeneity of genotypes, we assume that CNS isolated in this study could not be considered as important causative agents of the bovine mammary gland inflammation.

Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran.

PubMed

Mortazavi, Seyed Mohammad Javad; Zarei, Samira; Taheri, Mohammad; Tajbakhsh, Saeed; Mortazavi, Seyed Alireza; Ranjbar, Sahar; Momeni, Fatemeh; Masoomi, Samaneh; Ansari, Leila; Movahedi, Mohammad Mehdi; Taeb, Shahram; Zarei, Sina; Haghani, Masood

2017-04-01

Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium ( S. typhimurium ), Staphylococcus aureus , and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

Study on Prevalence, Antibiotic Susceptibility, and tuf Gene Sequence-Based Genotyping of Species-Level of Coagulase-Negative Staphylococcus Isolated From Keratitis Caused by Using Soft Contact Lenses.

PubMed

Faghri, Jamshid; Zandi, Alireza; Peiman, Alireza; Fazeli, Hossein; Esfahani, Bahram Nasr; Safaei, Hajieh Ghasemian; Hosseini, Nafiseh Sadat; Mobasherizadeh, Sina; Sedighi, Mansour; Burbur, Samaneh; Oryan, Golfam

2016-03-01

To study on antibiotic susceptibility and identify coagulase-negative Staphylococcus (CoNS) species based on tuf gene sequencing from keratitis followed by using soft contact lenses in Isfahan, Iran, 2013. This study examined 77 keratitis cases. The samples were cultured and the isolation of CoNS was done by phenotypic tests, and in vitro sensitivity testing was done by Kirby-Bauer disk diffusion susceptibility method. Thirty-eight of isolates were conveniently identified as CoNS. In this study, 27 (71.1%), 21 (55.3%), and 16 (42.1%) were resistant to penicillin, erythromycin, and tetracycline, respectively. One hundred percent of isolates were sensitive to gentamicin, and 36 (94.7%) and 33 (86.8%) of isolates were sensitive to chloramphenicol and ciprofloxacin, respectively. Also, resistances to cefoxitin were 7 (18.4%). Analysis of tuf gene proved to be discriminative and sensitive in which all the isolates were identified with 99.0% similarity to reference strains, and Staphylococcus epidermidis had the highest prevalence among other species. Results of this study showed that CoNS are the most common agents causing contact lens-associated microbial keratitis, and the tuf gene sequencing analysis is a reliable method for distinguishing CoNS species. Also gentamycin, chloramphenicol, and ciprofloxacin are more effective than the other antibacterial agents against these types of bacteria.

Drug resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolated from contact lenses in Karachi-Pakistan

PubMed Central

2013-01-01

Background The contaminated contact lens provides Pseudomonas aeruginosa an ideal site for attachment and biofilm production. Continuous contact of the eye to the biofilm-infested lens can lead to serious ocular diseases, such as keratitis (corneal ulcers). The biofilms also prevent effective penetration of the antibiotics, which increase the chances of antibiotic resistance. Methods For this study, 22 Pseudomonas aeruginosa isolates were obtained from 36 contact lenses and 14 contact lens protective fluid samples. These isolates were tested against eight commonly used antibiotics using Kirby-Bauer disk diffusion method. The biofilm forming potential of these isolates was also evaluated using various qualitative and quantitative techniques. Finally, a relationship between biofilm formation and antibiotic resistance was also examined. Results The isolates of Pseudomonas aeruginosa tested were found resistant to most of the antibiotics tested. Qualitative and quantitative biofilm analysis revealed that most of the isolates exhibited strong biofilm production. The biofilm production was significantly higher in isolates that were multi-drug resistant (p < 0.0001). Conclusion Our study indicates that multi-drug resistant, biofilm forming Pseudomonas aeruginosa isolates are mainly involved in contact lens associated infections. This appears to be the first report from Pakistan, which analyzes both antibiotic resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolates from contact lens of the patients with contact lens associated infections. PMID:24134792

Dynamics of conical wire array Z-pinch implosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ampleford, D. J.; Lebedev, S. V.; Bland, S. N.

2007-10-15

A modification of the wire array Z pinch, the conical wire array, has applications to the understanding of wire array implosions and potentially to pulse shaping relevant to inertial confinement fusion. Results are presented from imploding conical wire array experiments performed on university scale 1 MA generators--the MAGPIE generator (1 MA, 240 ns) at Imperial College London [I. H. Mitchell et al., Rev. Sci Instrum. 67, 1533 (1996)] and the Nevada Terawatt Facility's Zebra generator (1 MA, 100 ns) at the University of Nevada, Reno [B. Bauer et al., in Dense Z-Pinches, edited by N. Pereira, J. Davis, and P.more » Pulsifer (AIP, New York, 1997), Vol. 409, p. 153]. This paper will discuss the implosion dynamics of conical wire arrays. Data indicate that mass ablation from the wires in this complex system can be reproduced with a rocket model with fixed ablation velocity. Modulations in the ablated plasma are present, the wavelength of which is invariant to a threefold variation in magnetic field strength. The axial variation in the array leads to a zippered precursor column formation. An initial implosion of a magnetic bubble near the cathode is followed by the implosion zippering upwards. Spectroscopic data demonstrating a variation of plasma parameters (e.g., electron temperature) along the Z-pinch axis is discussed, and experimental data are compared to magnetohydrodynamic simulations.« less

Frequency of Resistance and Susceptible Bacteria Isolated from Houseflies

PubMed Central

Davari, B; Kalantar, E; Zahirnia, A; Moosa-Kazemi, SH

2010-01-01

Background: In this study, we determine the vector competence of Musca domestica with reference to the transmission of susceptible and resistance bacterial strains in hospitals and slaughter house in Sanandaj City, west Iran. Methods: Totally 908 houseflies were collected to isolate bacteria from their external body based on standard procedures.Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method on Mueller Hinton agar based on recommendations of CLSI (formerly the National Committee for Clinical Laboratory Standards). Results: From collected houseflies, 366 bacteria species were isolated. The most common isolated bacterium at hospitals was Klebsiella pneumoniae 43.3% (n= 90) followed by Pseudomonas aeruginosa 37% (n= 77), while that of slaughterhouse was Proteus mirabilis. 29.1% (n= 46) followed by Citrobacter freundii 28.4% (n= 45). Among all the isolates from hospitals, cephalexin, chloramphenicol, ampicillin, and tetracycline, resistance rates were above 32.5% and gentamicin expressed the highest susceptibility among all the isolates from hospitals. It is worth to note that K. pneumoniae showed 61% and 44.5% resistance to cephalexin and chloramphenicol respectively. Similarly, all isolates from slaughterhouse were more than 28% and 30% resistant to cephalexin and chloramphenicol respectively. Surprisingly, among all the isolates, Citrobacter freundii were highly resistant to gentamicin. Conclusion: Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria. PMID:22808400

Frequency of resistance and susceptible bacteria isolated from houseflies.

PubMed

Davari, B; Kalantar, E; Zahirnia, A; Moosa-Kazemi, Sh

2010-01-01

In this study, we determine the vector competence of Musca domestica with reference to the transmission of susceptible and resistance bacterial strains in hospitals and slaughter house in Sanandaj City, west Iran. Totally 908 houseflies were collected to isolate bacteria from their external body based on standard procedures.Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method on Mueller Hinton agar based on recommendations of CLSI (formerly the National Committee for Clinical Laboratory Standards). From collected houseflies, 366 bacteria species were isolated. The most common isolated bacterium at hospitals was Klebsiella pneumoniae 43.3% (n= 90) followed by Pseudomonas aeruginosa 37% (n= 77), while that of slaughterhouse was Proteus mirabilis. 29.1% (n= 46) followed by Citrobacter freundii 28.4% (n= 45). Among all the isolates from hospitals, cephalexin, chloramphenicol, ampicillin, and tetracycline, resistance rates were above 32.5% and gentamicin expressed the highest susceptibility among all the isolates from hospitals. It is worth to note that K. pneumoniae showed 61% and 44.5% resistance to cephalexin and chloramphenicol respectively. Similarly, all isolates from slaughterhouse were more than 28% and 30% resistant to cephalexin and chloramphenicol respectively. Surprisingly, among all the isolates, Citrobacter freundii were highly resistant to gentamicin. Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria.

Climatic Factors and Community — Associated Methicillin-Resistant Staphylococcus aureus Skin and Soft-Tissue Infections — A Time-Series Analysis Study

PubMed Central

Sahoo, Krushna Chandra; Sahoo, Soumyakanta; Marrone, Gaetano; Pathak, Ashish; Lundborg, Cecilia Stålsby; Tamhankar, Ashok J.

2014-01-01

Skin and soft tissue infections caused by Staphylococcus aureus (SA-SSTIs) including methicillin-resistant Staphylococcus aureus (MRSA) have experienced a significant surge all over the world. Changing climatic factors are affecting the global burden of dermatological infections and there is a lack of information on the association between climatic factors and MRSA infections. Therefore, association of temperature and relative humidity (RH) with occurrence of SA-SSTIs (n = 387) and also MRSA (n = 251) was monitored for 18 months in the outpatient clinic at a tertiary care hospital located in Bhubaneswar, Odisha, India. The Kirby-Bauer disk diffusion method was used for antibiotic susceptibility testing. Time-series analysis was used to investigate the potential association of climatic factors (weekly averages of maximum temperature, minimum temperature and RH) with weekly incidence of SA-SSTIs and MRSA infections. The analysis showed that a combination of weekly average maximum temperature above 33 °C coinciding with weekly average RH ranging between 55% and 78%, is most favorable for the occurrence of SA-SSTIs and MRSA and within these parameters, each unit increase in occurrence of MRSA was associated with increase in weekly average maximum temperature of 1.7 °C (p = 0.044) and weekly average RH increase of 10% (p = 0.097). PMID:25177823

Gold and silver nanoparticles from Trianthema decandra: synthesis, characterization, and antimicrobial properties

PubMed Central

Geethalakshmi, R; Sarada, DVL

2012-01-01

Background There is an increasing commercial demand for nanoparticles due to their wide applicability in various markets, including medicine, catalysis, electronics, chemistry, and energy. In this report, a simple and ecofriendly chemical reaction for the synthesis of gold and silver nanoparticles from Trianthema decandra (Aizoaceae) has been developed. Methods and results On treatment of aqueous solutions containing chloroauric acid or silver nitrate with root extract of T. decandra, stable gold or silver nanoparticles were rapidly formed. The kinetics of reduction of gold and silver ions during the reaction was analyzed by ultraviolet-visible spectroscopy. Field emission-scanning electron microscopy showed formation of gold nanoparticles in various shapes, including spherical, cubical, triangular, and hexagonal, while silver nanoparticles were spherical. The size of the gold nanoparticles was 33–65 nm and that of the silver nanoparticles was 36–74 nm. Energy dispersive x-ray and Fourier transform infrared spectroscopy confirmed the presence of metallic gold and metallic silver in the respective nanoparticles. The antimicrobial properties of the synthesized nanoparticles were analyzed using the Kirby-Bauer method. The results show varied susceptibility of microorganisms to the gold and silver nanoparticles. Conclusion It is believed that phytochemicals present in T. decandra extract reduce the silver and gold ions into metallic nanoparticles. This strategy reduces the cost of production and the environmental impact. The silver and gold nanoparticles formed showed strong activity against all microorganisms tested. PMID:23091381

Characterization and susceptibility patterns of clinically important Enterococcus species in eastern Nepal.

PubMed

Acharya, A; Khanal, A; Kanungo, R; Mohapatra, T

2007-12-01

Life threatening infections caused by enterococcus species with multidrug resistance has emerged as a threat to medical care in the present era. This study was conducted to characterize enterococcus species isolated from different clinical samples and to detect the pattern of susceptibility to some of the commonly used antibiotics in B.P Koirala Institute of Health Sciences (BPKIHS), a tertiary care hospital in eastern Nepal. Clinical samples submitted to the microbiology unit of Central Laboratory Service (CLS) for culture and sensitivity during March 2002 - February 2003 was analyzed. Enterococcus species were identified by colony characteristics, gram staining and relevant biochemical tests. Antibiotic susceptibility test was done by the Kirby Bauer disc diffusion technique. Of 50 Enterococcus species isolated, E. faecalis was the predominant isolate (48.0%) followed by E. faecium (32.0%) and E. avium (20.0%). Eighty-eight percent of E. faecalis showed sensitivity to cephotaxime and 87.0% to vancomycin. Multiple drug resistance was observed most commonly in E. faecium. Seventeen percent of E. faecium were resistant to vancomycin and 63.0% to ciprofloxacin and 44.0% to ampicillin. On the contrary E. avium rarely showed resistance to the antimicrobials tested including vancomycin. Enterococcal infections are common nowadays specially in hospitalized patients. Inappropriate use of antibiotics in clinical practice and poultry should be discouraged to prevent the emergence of multidrug resistant species.

[Antagonism against Beauveria bassiana by lipopeptide metabolites produced by entophyte Bacillus amyloliquefaciens strain SWB16].

PubMed

Wang, Jingjie; Zhao, Dongyang; Liu, Yonggui; Ao, Xiang; Fan, Rui; Duan, Zhengqiao; Liu, Yanping; Chen, Qianqian; Jin, Zhixiong; Wan, Yongji

2014-07-04

We screened bacterial strains that have strong antagonism against Beauveria bassiana, an important pathogen of silkworm industry, and detected the antagonistic activity of lipopeptide metabolites. We identified bacterium SWB16 by morphological observation, physiological and biochemical experiments, 16SrRNA, and gyrA gene sequence analysis, tested antagonistic activity of strain SWB16 against Beauveria bassiana by measuring the inhibition zone diameter using filter paper diffusion method (Kirby-Bauer method), obtained lipopeptide metabolites of the strain using methanol extraction and observed the antagonism of strain SWB16 lipopeptide extracts against the conidia and hyphae of Beauveria bassiana, detected main ingredients and genes of lipopeptide metabolites by high-performance liquid chromatography-mass spectrometry and PCR amplification. SWB16 isolated from tissue of plant Dioscorea zingiberensis C. H. Wright belongs to Bacillus amyloliquefaciens and showed high antagonistic activity to Beauveria bassiana, and the lipopeptide extracts of isolate SWB16 exhibited significant inhibition to conidial germination and mycelial growth of Beauveria bassiana. The result of mass spectrometric detection indicated main component of the lipopeptide metabolites were fengcin and iturin, and genes fenB, ituA involved in the synthesis of them were amplified in the genome. Bacillus amyloliquefaciens strain SWB16 could produce lipopeptide antibiotics with strong antagonism to the entomopathogenic fungus Beauveria bassiana, and the results suggested that strain SWB16 has potential application value for controlling white muscardine of economic insects including silkworm.

Lyotropic liquid crystal preconcentrates for the treatment of periodontal disease.

PubMed

Fehér, A; Urbán, E; Eros, I; Szabó-Révész, P; Csányi, E

2008-06-24

The aim of our study was to develop water-free lyotropic liquid crystalline preconcentrates, which consist of oils and surfactants with good physiological tolerance and spontaneously form lyotropic liquid crystalline phase in aqueous environment. In this way these preconcentrates having low viscosity can be injected into the periodontal pocket, where they are transformed into highly viscous liquid crystalline phase, so that the preparation is prevented from flowing out of the pocket due to its great viscosity, while drug release is controlled by the liquid crystalline texture. In order to follow the structure alteration upon water absorption polarization microscopical and rheological examinations were performed. The water absorption mechanism of the samples was examined by the Enslin-method. Metronidazole-benzoate was used as active agent the release of which was characterized via in vitro investigations performed by means of modified Kirby-Bauer disk diffusion method. On the grounds of the results it can be stated that the 4:1 mixture of the investigated surfactants (Cremophor EL, Cremophor RH40) and oil (Miglyol 810) formed lyotopic liquid crystalline phases upon water addition. Polarization microscopic examinations showed that samples with 10-40% water content possessed anisotropic properties. On the basis of water absorption, rheological and drug release studies it can be concluded that the amount of absorbed water and stiffness of lyotropic structure influenced by the chemical entity of the surfactant exerted major effect on the drug release.

Beta-haemolytic group A streptococci emm75 carrying altered pyrogenic exotoxin A linked to scarlet fever in adults.

PubMed

Dong, Hongjun; Xu, Guozhang; Li, Shuhua; Song, Qifa; Liu, Shijian; Lin, Hui; Chai, Yibiao; Zhou, Aimin; Fang, Ting; Zhang, Hongwei; Jin, Chunguang; Lu, Wei; Cao, Guangwen

2008-04-01

To determine the etiological cause of a food-borne outbreak of scarlet fever in adults. Swabs from the throats of the patients and asymptomatic control were cultured on blood agar plates individually. Biochemical identification of all isolates was performed with a VITEX automated system. Antibiotic susceptibility was examined by using the Kirby-Bauer disc diffusion method. emm gene and extracellular pyrogenic exotoxins of each isolate were amplified by using polymerase chain reaction and subjected to DNA sequencing. Sequence differences between the isolated and the highly similar reference sequences were compared on BLAST. Bioinformatics was used to predict protein structures. Beta-haemolytic group A streptococci (GAS) emm75 were identified from 10 of 13 available patients. The isolates were susceptible to penicillin, ampicillin, vancomycin, cefatriaxone, ofloxacin, linezolid and quinupristin. All of the isolates carried pyrogenic exotoxin A (speA) and cysteine protease (speB). Isolated speA was phylogenetically different from 30 highly similar references on BLAST. Differences in the primary sequence of the deduced protein were 14.37-20.12% between the speA and each of 11 references. Secondary protein structure of the speA was different from the references at the N-terminal. GAS emm75 encoding altered speA was responsible for the food-borne outbreak of scarlet fever in adults.

Imipenem Resistant Pseudomonas aeruginosa: The fall of the final quarterback.

PubMed

Ameen, Nadya; Memon, Zahida; Shaheen, Shehla; Fatima, Ghulam; Ahmed, Farah

2015-01-01

To isolate, determine the frequency, and study the demographic trends of MBL positive Pseudomonas aeruginosa from imipenem resistant isolates collected from clinical samples in a tertiary care hospital of Pakistan. In this cross sectional study a total of 230 strains of Pseudomonas were isolated from various clinical specimens on the basis of culture and biochemical tests. Imipenem resistant isolates were selected by Kirby Bauer Diffusion technique, followed by screening for MBL production by Imipenem EDTA Combined Disk Test. Demographic details of each patient were recorded on a separate questionnaire. Chi-Square goodness-of-fit test was computed to review the isolation of MBL positive isolates (P-value ≤ 0.05) in different specimen. Out of 230 strains of P. aeruginosa 49.5% were imipenem resistant; MBL production was confirmed in 64.9% of the resistant isolates. Resistance to polymyxin B (12.5%) was notable. Majority of the MBL positive strains were isolated from patients aged between 20-39 years (45.9%) and the predominant source was pus (43.24%) which was found to be statistically significant (P-value=0.04). Outpatient departments (24.3%) and burn unit (21.6%) were the major places for resistant isolates. MBL production is one of the major causes of IRPA. Increasing resistance to polymyxin B is grave. Due to acquisition of MBL strains MDR P. aeruginosa has become endemic in tertiary setups.

Imipenem Resistant Pseudomonas aeruginosa: The fall of the final quarterback

PubMed Central

Ameen, Nadya; Memon, Zahida; Shaheen, Shehla; Fatima, Ghulam; Ahmed, Farah

2015-01-01

Objective: To isolate, determine the frequency, and study the demographic trends of MBL positive Pseudomonas aeruginosa from imipenem resistant isolates collected from clinical samples in a tertiary care hospital of Pakistan. Methods: In this cross sectional study a total of 230 strains of Pseudomonas were isolated from various clinical specimens on the basis of culture and biochemical tests. Imipenem resistant isolates were selected by Kirby Bauer Diffusion technique, followed by screening for MBL production by Imipenem EDTA Combined Disk Test. Demographic details of each patient were recorded on a separate questionnaire. Chi-Square goodness-of-fit test was computed to review the isolation of MBL positive isolates (P-value ≤ 0.05) in different specimen. Results: Out of 230 strains of P. aeruginosa 49.5% were imipenem resistant; MBL production was confirmed in 64.9% of the resistant isolates. Resistance to polymyxin B (12.5%) was notable. Majority of the MBL positive strains were isolated from patients aged between 20-39 years (45.9%) and the predominant source was pus (43.24%) which was found to be statistically significant (P-value=0.04). Outpatient departments (24.3%) and burn unit (21.6%) were the major places for resistant isolates. Conclusion: MBL production is one of the major causes of IRPA. Increasing resistance to polymyxin B is grave. Due to acquisition of MBL strains MDR P. aeruginosa has become endemic in tertiary setups. PMID:26150844

Size- and Shape-Dependent Antibacterial Studies of Silver Nanoparticles Synthesized by Wet Chemical Routes

PubMed Central

Raza, Muhammad Akram; Kanwal, Zakia; Rauf, Anum; Sabri, Anjum Nasim; Riaz, Saira; Naseem, Shahzad

2016-01-01

Silver nanoparticles (AgNPs) of different shapes and sizes were prepared by solution-based chemical reduction routes. Silver nitrate was used as a precursor, tri-sodium citrate (TSC) and sodium borohydride as reducing agents, while polyvinylpyrrolidone (PVP) was used as a stabilizing agent. The morphology, size, and structural properties of obtained nanoparticles were characterized by scanning electron microscopy (SEM), UV-visible spectroscopy (UV-VIS), and X-ray diffraction (XRD) techniques. Spherical AgNPs, as depicted by SEM, were found to have diameters in the range of 15 to 90 nm while lengths of the edges of the triangular particles were about 150 nm. The characteristic surface plasmon resonance (SPR) peaks of different spherical silver colloids occurring in the wavelength range of 397 to 504 nm, whereas triangular particles showed two peaks, first at 392 nm and second at 789 nm as measured by UV-VIS. The XRD spectra of the prepared samples indicated the face-centered cubic crystalline structure of metallic AgNPs. The in vitro antibacterial properties of all synthesized AgNPs against two types of Gram-negative bacteria, Pseudomonas aeruginosa and Escherichia coli were examined by Kirby–Bauer disk diffusion susceptibility method. It was noticed that the smallest-sized spherical AgNPs demonstrated a better antibacterial activity against both bacterial strains as compared to the triangular and larger spherical shaped AgNPs. PMID:28335201

Distribution and Antimicrobial Susceptibility Pattern of Bacterial Pathogens Causing Urinary Tract Infection in Urban Community of Meerut City, India

PubMed Central

Prakash, Devanand; Saxena, Ramchandra Sahai

2013-01-01

Urinary tract infection is one of the common infections in the Indian community. Distribution and susceptibility of UTI-causing pathogens change according to time and place. This study was conducted to determine the distribution and antimicrobial susceptibility of uropathogens in the Indian community as well as to determine the effect of gender and age on the etiology of bacterial uropathogens. Clean catch midstream urine samples were collected from 288 patients of the age ranging from 15 to ≥48 years. Antimicrobial susceptibility was performed on all isolated bacteria by Kirby Bauer's disc diffusion method. The multiple antibiotic resistance (MAR) index of each antibiotic was calculated. The UTI prevalence was 53.82% in patients; however, the prevalence was significantly higher in females than in males (females: 73.57%; males: 35.14%; P = 0.000). Females within the age group of 26–36 years and elderly males of ≥48 years showed higher prevalence of UTI. Gram negative bacteria (90.32%) were found in high prevalence than Gram positive (9.68%). Escherichia coli (42.58%) was the most prevalent gram negative isolate. Nitrofurantoin (78.71%) was found the most resistant drug among all uropathogens. Tested carbapenems were found the most susceptible drug against isolated uropathogens which showed 92.26% and 84.52% susceptibility, respectively. PMID:24288649

A liposomal hydrogel for the prevention of bacterial adhesion to catheters.

PubMed

DiTizio, V; Ferguson, G W; Mittelman, M W; Khoury, A E; Bruce, A W; DiCosmo, F

1998-10-01

The adhesion of bacteria to medical implants and the subsequent development of a biofilm frequently results in the infection of surrounding tissue and may require removal of the device. We have developed a liposomal hydrogel system that significantly reduces bacterial adhesion to silicone catheter material. The system consists of a poly (ethylene glycol)-gelatin hydrogel in which liposomes containing the antibiotic ciprofloxacin are sequestered. A poly (ethylene glycol)-gelatin-liposome mixture was applied to a silicone surface that had been pre-treated with phenylazido-modified gelatin. Hydrogel cross-linking and attachment to surface-immobilized gelatin was accomplished through the formation of urethane bonds between gelatin and nitrophenyl carbonate-activated poly (ethylene glycol). Liposomal hydrogel-coated catheters were shown to have an initial ciprofloxacin content of 185+/-16 microg cm(-2). Ciprofloxacin was released over seven days with an average release rate of 1.9+/-0.2 microg cm(-2) h(-1) for the first 94 h. In vitro assays using a clinical isolate of Pseudomonas aeruginosa established the antimicrobial efficacy of the liposomal hydrogel. A modified Kirby-Bauer assay produced growth-inhibition zone diameters of 39+/-1 mm, while bacterial adhesion was completely inhibited on catheter surfaces throughout a seven-day in vitro adhesion assay. This new antimicrobial coating shows promise as a prophylactic and/or treatment for catheter-related infection.

TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE AND FOSFOMYCIN SUSCEPTIBILITY RATES IN UNCOMPLICATED URINARY TRACT INFECTIONS: TIME TO CHANGE THE ANTIMICROBIAL PREFERENCES.

PubMed

Guneysel, Ozlem; Suman, Enes; Ozturk, Tuba Cimilli

2016-03-01

Urinary tract infections (UTIs) are among the most common bacterial infections in adult population. They are prevalent in all age groups both in women and men. Also, UTIs are the most frequent indication for empirical antibiotic treatment in emergency department. The aim of this study was to determine the antibiotic resistance rates in the treatment of uncomplicated UTIs. Adult patients admitted to emergency department with uncomplicated UTIs were included in this cross-sectional study. Mid-stream urine samples were obtained under sterile conditions and cultured quantitatively. After 24 hours, the samples showing 10(5) colony forming unit per milliliter (CFU/mL) were tested for antibiotic susceptibility. Resistance to fosfomycin-trometamol (FT), amoxicillin-clavulanic acid (AC), ciprofloxacin (CIP), trimethoprim-sulfamethoxazole (TMP-SMX) and cefpodoxime (CEF) was tested by Kirby-Bauer disc diffusion system. Escherichia (E.) coli accounted for the vast majority (93.4%) of the organisms isolated in the study. Among the E. coli positive patients, resistance to TMP-SMX was the most common antibiotic resistance. The E. coli species detected in our study group were least resistant to FT (2.4%). The resistance rates, especially to CEF, AC and CIP, were significantly higher in patients over 50 years of age. In conclusion, in the treatment of uncomplicated UTIs, TMP-SMX should be excluded from empirical treatment, while fosfomycin could be a viable option in all age groups.

Biosynthesis of silver nanoparticles from Tribulus terrestris and its antimicrobial activity: a novel biological approach.

PubMed

Gopinath, V; MubarakAli, D; Priyadarshini, S; Priyadharsshini, N Meera; Thajuddin, N; Velusamy, P

2012-08-01

In the recent decades, increased development of green synthesis of nanoparticles is inevitable because of its incredible applications in all fields of science. There were numerous work have been produced based on the plant and its extract mediated synthesis of nanoparticles, in this present study to explore that the novel approaches for the biosynthesis of silver nanoparticles using plant fruit bodies. The plant, Tribulus terrestris L. fruit bodies are used in this study, where the dried fruit body extract was mixed with silver nitrate in order to synthesis of silver nanoparticles. The active phytochemicals present in the plant were responsible for the quick reduction of silver ion (Ag(+)) to metallic silver nanoparticles (Ag(0)). The reduced silver nanoparticles were characterized by Transmission Electron Microscope (TEM), Atomic Force Microscope (AFM), XRD, FTIR, UV-vis spectroscopy. The spherical shaped silver nanoparticles were observed and it was found to be 16-28 nm range of sizes. The diffraction pattern also confirmed that the higher percentage of silver with fine particles size. The antibacterial property of synthesized nanoparticles was observed by Kirby-Bauer method with clinically isolated multi-drug resistant bacteria such as Streptococcus pyogens, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus aureus. The plant materials mediated synthesis of silver nanoparticles have comparatively rapid and less expensive and wide application to antibacterial therapy in modern medicine. Copyright © 2012 Elsevier B.V. All rights reserved.

New look at the Badger-Bauer rule: Correlations of spectroscopic IR and NMR parameters with hydrogen bond energy and geometry. FHF complexes

NASA Astrophysics Data System (ADS)

Tupikina, E. Yu.; Denisov, G. S.; Melikova, S. M.; Kucherov, S. Yu.; Tolstoy, P. M.

2018-07-01

In this work correlation dependencies between hydrogen bond energy ΔE for complexes with Fsbnd H⋯F hydrogen bond and their spectroscopic characteristics of the IR and NMR spectra are presented. We considered 26 complexes in a wide hydrogen bond energy range 0.2-47 kcal/mol. For each complex we calculated complexation energy (MP2/6-311++G(d,p)), IR spectroscopic parameters (FH stretching frequency ν, FH stretching frequency in local mode approximation νLM at MP2/6-311++G(d,p) level) and NMR parameters (chemical shift of hydrogen δH and fluorine nuclei δF, Nuclear Independent Chemical Shielding and spin-spin coupling constants 1JFH, 1hJH...F, 2hJFF at B3LYP/pcSseg-2 level). It was shown that changes of parameters upon complexation, i.e. changes of the stretching frequency in local mode approximation ΔνLM, change of the proton chemical shift ΔδH and change of the absolute value of spin-spin coupling constant 1JFH could be used for estimation of corresponding hydrogen bond strength. Furthermore, we build correlation dependencies between abovementioned spectroscopic characteristics and geometric ones, such as the asymmetry of bridging proton position q1 = 0.5·(rFH - rH…F).

Antimicrobial Effect of Lactobacillus reuteri on Cariogenic Bacteria Streptococcus gordonii, Streptococcus mutans, and Periodontal Diseases Actinomyces naeslundii and Tannerella forsythia.

PubMed

Baca-Castañón, Magda Lorena; De la Garza-Ramos, Myriam Angélica; Alcázar-Pizaña, Andrea Guadalupe; Grondin, Yohann; Coronado-Mendoza, Anahí; Sánchez-Najera, Rosa Isela; Cárdenas-Estrada, Eloy; Medina-De la Garza, Carlos Eduardo; Escamilla-García, Erandi

2015-03-01

Lactic acid bacteria (LAB) are well known for their beneficial effects on human health in the intestine and immune system; however, there are few studies on the impact they can generate in oral health. The aim of this study was to test and compare in vitro antimicrobial activity of L. reuteri on pathogenic bacteria involved in the formation of dental caries: S. mutans, S. gordonii, and periodontal disease: A. naeslundii and T. forsythia. Also, we determined the growth kinetics of each bacterium involved in this study. Before determining the antimicrobial action of L. reuteri on cariogenic bacteria and periodontal disease, the behavior and cell development time of each pathogenic bacterium were studied. Once the conditions for good cell growth of each of selected pathogens were established according to their metabolic requirements, maximum exponential growth was determined, this being the reference point for analyzing the development or inhibition by LAB using the Kirby Bauer method. Chlorhexidine 0.12% was positive control. L. reuteri was shown to have an inhibitory effect against S. mutans, followed by T. forsythia and S. gordonii, and a less significant effect against A. naeslundii. Regarding the effect shown by L. reuteri on the two major pathogens, we consider its potential use as a possible functional food in the prevention or treatment of oral diseases.

Protracted or multiple subduction of metapelites (Rhodope UHP domain, Greece)?

NASA Astrophysics Data System (ADS)

Krohe, A.; Wawrzenitz, N. H.; Mposkos, E.; Romer, R. L.

2012-12-01

The Rhodope domain formed along the suture between the European and the Apulian/Adriatic plate, which collided in the early Tertiary (closure of the Vardar/Axios ocean). Its metamorphic history includes UHP metamorphism documented by diamond inclusions in garnet (Mposkos & Kostopoulos 2001, Perraki et al. 2006, Schmidt et al. 2010), presumably of Jurassic age, and Eocene stages of MP and HP metamorphism. The age of UHPM is still a matter of debate: U-Pb SHRIMP ages extend from 184-172 Ma (monazite in metapelites) to ca. 42 Ma with clusters at 170-160, 150-140, 80-60, 50, 42 Ma, (U-Pb SHRIMP dating of zircon from amphibolitized eclogites and metapelites). These ages are interpreted to date subsequent stages of (U)HP metamorphism and decompression (Liati et al., 2005, Hoinkes et al. 2008, Bauer et al. 2006, Krenn et al 2010). However, these ages are obviously difficult to link with the metamorphic reactions. The metamorphic history has been interpreted in different ways, reflecting: (i) successive accretion of small terranes with rapid subduction and uplift histories (e.g. Liati et al. 2005); (ii) a composite of different tectonic units varying in earlier P-T histories, assembled by shear zones that reflect tectonic erosion and differential exhumation along the plate interface and that are now erased and overprinted (Krohe and Mposkos, 2002, Mposkos et al., 2010). These interpretations imply a different kinematics of the tectonic movements at depths, mechanical processes and process rates. Additionally, a protracted polymetamorphic history of larger volumes of the Rhodope UHP domain may be considered; e.g. the Kimi complex stayed in the lower crust for ca. 50-60 Ma after exhumation of the UHP rocks to this lower crustal level (Mposkos and Krohe, 2006). To constrain a precise age of the HP granulite facies and a minimum age of UHP metamorphism, we conduct an integrated structural, petrologic and geochronological study in a metapelite from the Sidronero Complex. The mineral assemblages Grt-Ky-Bt-Pl-Kfs-Qtz-Rt and Grt-Ky-Bt-Ms-Pl-Qtz-Rt, record a HP granulite facies metamorphism followed by upper amphibolite facies. The rock is particularly well suited for studying the granulite facies metamorphism, as it contains domains that are only weakly overprinted by later metamorphic episodes. ID-TIMS U-Pb ages of single monazite grains and fractions of few grains, that are only locally patchy-zoned and associated with garnet and kyanite, plot along the concordia between 64 to 60 Ma. One date of 55 Ma might represent Pb-loss during later fluid-induced dissolution-reprecipitation, probably related to biotite growth during the amphibolite facies overprint. On the base of these data, a model is discussed, in which rocks from the upper plate and HP-rocks that have been already exhumed, were dragged again into the subduction channel by subduction erosion Bauer et al. 2006, Lithos, 29, 207-228; Hoinkes et al. 2008, 3rd IGC Oslo, UHP-4; Krenn et al 2010, Tectonics, 29, TC4001; Krohe & Mposkos, 2002, Geol. Soc. Sp. Pub. 204, 151-178; Liati, A., 2005, Contrib. Mineral. Petrol., 150, 608-630; Mposkos, & Kostopoulos, 2001, EPSL, 192, 497-506; Mposkos & Krohe, 2006. Can. J. Earth Sci., 43, 1755-1776; Mposkos et al., 2010 Proc. XIX CBGA Congress, 100, 173-178; Perraki et al., 2006, EPSL, 241, 672-685; Schmidt et al., 2010, EJM, 22, 189-198.

The Protective Effect of Kevlar ® Socks Against Hockey Skate Blade Injuries: A Biomechanical Study

PubMed Central

Nauth, Aaron; Aziz, Mina; Tsuji, Matthew; Whelan, Daniel B.; Theodoropoulos, John S.; Zdero, Rad

2014-01-01

Objectives: Several recent high profile injuries to elite players in the National Hockey League (NHL) secondary to skate blade lacerations have generated significant interest in these injuries and possible methods to protect against them. These injuries are typically due to direct contact of the skate blade of another player with posterior aspect of the calf resulting in a range of potential injuries to tendons or neurovascular structures. The Achilles tendon is most commonly involved. Kevlar® reinforced socks have recently become available for hockey players to wear and are cited as providing possible protection against such injuries. However, there has been no investigation of the possible protective effects of Kevlar® reinforced socks against skate blade injuries, and it is currently unknown what protective effects, if any, that these socks provide against these injuries. The proposed study sought to address this by conducting a biomechanical investigation of the protective effects of Kevlar® reinforced socks against Achilles tendon injuries in a simulated model of skate blade injury using human cadaver limbs. This novel investigation is the first to address the possible benefits to hockey players of wearing Kevlar® reinforced socks. Methods: Seven matched pairs of human cadaver lower limbs were fitted with a Kevlar ® reinforced sock comprised of 60% Kevlar®/20% Coolmax® polyester/18 % Nylon/12% Spandex (Bauer Elite Performance Skate Sock) on one limb and a standard synthetic sock comprised of 51% polyester/47% nylon/2% spandex (Bauer Premium Performance Skate Sock) on the contralateral limb as a control. Each limb was then mounted on a Materials Testing System (MTS) with the ankle dorsiflexed to 90° and the knee held in full extension using a custom designed jig. Specimens were then impacted with a hockey skate blade directed at the posterior calf, 12 cm above the heel, at an angle of 45° and a speed of 31m/s, to a penetration depth of 4.3 cm, to simulate a typical ice hockey injury. Peak force, energy and power were calculated from the force-displacement data collected from the 7 matched pair trials. The cadavers were then dissected to identify the extent of the injury the skin and Achilles tendon from blade impact. Analysis of variance was used to test for a significant difference between the groups. Results: None (0/7) of the achilles tendons were lacerated when protected with Kevlar® reinforced socks; whereas all (7/7) achilles tendons tested using the standard synthetic sock were completely severed (Figure 1). Peak force (4030 +/- 1191 N vs. 2037 +/- 729 N), energy (81.4 +/- 38.9 J vs. 26.3 +/- 13.2 J) and power (471.2 +/- 166.7 W vs. 258.3 +/- 93.5 W) were all significantly (p<0.05) increased in the Kevlar® reinforced sock group compared to the standard synthetic sock group in our testing model (Figures 2 and 3). Conclusion: The Kevlar® reinforced socks provided significantly more cut resistance and were able to withstand a significantly larger peak force, energy and power from skate blade impact and prevent achilles tendon laceration when compared to standard synthetic hockey socks in a biomechanical testing model using human cadaver limbs. This is the first investigation to address the benefits of wearing Kevlar® reinforced hockey socks in a simulated model of hockey skate injuries and our results suggest a significant protective effect from the use of Kevlar® reinforced socks against hockey skate injuries.

PREFACE: The 16th International Symposium on Boron, Borides and Related Materials (ISBB 2008)

NASA Astrophysics Data System (ADS)

Tanaka, Takaho

2009-07-01

This volume of Journal of Physics: Conference Series contains invited and contributed peer-reviewed papers that were presented at the 16th International Symposium on Boron, Borides and Related Materials (ISBB 2008), which was held on 7-12 September 2008, at Kunibiki Messe, Matsue, Japan. This triennial symposium has a half-century long history starting from the 1st meeting in 1959 at Asbury Park, New Jersey. We were very pleased to organize ISBB 2008, which gathered chemists, physicists, materials scientists as well as diamond and high-pressure researchers. This meeting had a strong background in the boron-related Japanese research history, which includes the discovery of superconductivity in MgB2 and development of Nd-Fe-B hard magnets and of YB66 soft X-ray monochromator. The scope of ISBB 2008 spans both basic and applied interdisciplinary research that is centered on boron, borides and related materials, and the collection of articles defines the state of the art in research on these materials. The topics are centered on: 1. Preparation of new materials (single crystals, thin films, nanostructures, ceramics, etc) under normal or extreme conditions. 2. Crystal structure and chemical bonding (new crystal structures, nonstoichiometry, defects, clusters, quantum-chemical calculations). 3. Physical and chemical properties (band structure, phonon spectra, superconductivity; optical, electrical, magnetic, emissive, mechanical properties; phase diagrams, thermodynamics, catalytic activity, etc) in a wide range of temperatures and pressures. 4. Applications and prospects (thermoelectric converters, composites, ceramics, coatings, etc) There were a few discoveries of new materials, such as nanomaterials, and developments in applications. Many contributions were related to 4f heavy Fermion systems of rare-earth borides. Exotic mechanisms of magnetism and Kondo effects have been discussed, which may indicate another direction of development of boride. Two special sessions, 'Boron chemistry' and 'Superconductivity', were also held at the symposium. The session on Boron chemistry was planned to honor the scientific work in boron chemistry of Professor J Bauer on the occasion of his retirement. Many recent results were discussed in the session, and Professor Bauer himself introduced novel rare-earth-boron-carbon compounds RE10B7C10 (RE = Gd - Er) in his lecture. In the latter session, on the basis of recent discoveries of superconductivity in MgB2 and in β-boron under high pressure, the superconductivity of boron and related materials was discussed and the superconductivity of boron-doped diamond was also addressed. More than 120 participants from 16 countries attended the ISBB 2008, and active presentations (22 invited, 33 oral and 68 posters) and discussions suggest that research on boron and borides is entering a new phase of development. This volume contains 46 articles from 52 submitted manuscripts. The reviewers were invited not only from symposium participants but also from specialists worldwide, and they did a great job of evaluating and commenting on the submitted manuscripts to maintain the highest quality standard of this volume. Recent discoveries of superconductivity in boron under high pressure, synthesis of a new allotrope of boron and of various boron and boride nanostructures will lead this highly interdisciplinary field of science, which will further grow and gain attention in terms of both basic and applied research. In this context, we are very much looking forward to the next symposium, which will be held in Istanbul, Turkey, in 2011, organized by Professor Onuralp Yucel, Istanbul Technical University. Turkey currently has the world highest share of borate production and is expected to be involved more in boron-related research. Acknowledgements We gratefully acknowledge the style improvement by Dr K Iakoubovskii, and sincerely thank Shimane Prefecture and Matsue City for their financial support. The symposium was also supported by Tokyo University of Science, Suwa and foundations including, the Kajima Foundation, Foundation for Promotion of Material Science and Technology of Japan and Nippon Sheet Glass Foundation for Materials Science and Engineering, as well as companies including JFE Steel Corporation, Shincron Co, Ltd, Toyo Kohan Co, Ltd, Fukuda Metal Foil and Powder Co, Ltd, Japan New Metals Co, Ltd, H C Starck Ltd and Fritsch Japan Co, Ltd. Editors Chair Takaho Tanaka (National Institute for Materials Science, Japan) Vice chairs Koun Shirai (Osaka University, Japan) Kaoru Kimura (The University of Tokyo, Japan) Ken-ichi Takagi (Tokyo City University, Japan) Touetsu Shishido (Tohoku University, Japan) Shigeru Okada (Kokushikan University) Hideaki Itoh (Nagoya University,Japan) Katsumitsu Nakamura (Nihon University, Japan) Organizing committee of ISBB 2008 K Takagi Chairman (Tokyo City University) T Tanaka Program Committee Chairman (National Institute for Materials Science) K Kimura Secretary (The University of Tokyo) J Akimitsu (Aoyama University)K Shirai (Osaka University) H Itoh (Nagoya University)T Shishido (Tohoku University) K Nakamura (Nihon University)K Soga (Tokyo University of Science) K Nishiyama (Tokyo University of Science, Suwa)M Takeda (Nagaoka University of Technology) S Okada (Kokushikan University)Y Yamazaki (Toyo Kohan Co, Ltd) International Scientific Committee 0f ISBB (2008-2011) K Takagi Chairman (Japan) B Albert (Germany) J-F Halet (France) M Takeda (Japan) M Antadze (Georgia) H Hillebrecht (Germany) T Tanaka (Japan) J Bauer (France) W Jung (Germany) R Telle (Germany) I Boustani (Germany) K Kimura (Japan) M Trenary (USA) D Emin (USA) T Mori (Japan) O Tsagareishvili (Georgia) M Engler (Germany) P D Ownby (USA) H Werheit (Germany) N Frage (Israel) P Rogl (Austria) G Will (Germany) Yu Grin (Germany) S Shalamberidze (Georgia) O Yucel (Turkey) V N Gurin (Russia) N Shitsevalova (Ukraine) G Zhang (China)

Fiber Length Measurement In Pulp And Paper Industry

NASA Astrophysics Data System (ADS)

Piirainen, Raili A.

1986-10-01

For the pulp and paper maker, product quality and production costs are the major factors that determine profitability. Quality has to be high enough to satisfy the customer and costs low enough to maintain competitiveness. Accurate and readily available fiber length information is fast becoming one of the most important control factors to achieve these targets. Measurement of fiber length has been difficult and time consuming in the past --- appli-cation to production almost impossible due to the historical nature of the data. The Kajaani fiber length analyzer has revolutionized fiber length analysis. Even more accurate than the microscopic method and infinitely faster than mechanical classifiers, such as Bauer McNett or Clark classifiers, the Kajaani analyzer opens new horizons for the paper maker. The Kajaani method is an optical method and is based on the ability of fibers to change the direction of light polarization. With no critical sample preparation, the results are ready in a few minutes. During this time, the analyzer counts and measures over 3000 individual fibers. Results are printed out either in graphic or numerical form. Some of the typical applications of the Kajaani fiber length analyzer are to determine hardwood/softwood ratios in pulp and paper mills both in brownstock and stock preparation areas, to predict strength properties of mechanical pulp based on the fiber length information, to measure the coarseness of the fibers, to evaluate screening and refining processes and to check the quality of purchased pulp.

Synergy between antibiotics and natural agents results in increased antimicrobial activity against Staphylococcus epidermidis.

PubMed

Abidi, Syed Hani; Ahmed, Khalid; Sherwani, Sikander Khan; Kazmi, Shahana Urooj

2015-09-27

Staphylococcus epidermidis is one of the most frequent causes of biofilm-associated infections on indwelling medical devices. With the emergence of methicillin-resistant S. epidermidis (MRSE), there is an urgent need to discover novel active agents against a range of Gram-positive pathogens. We screened the clinical isolates of S. epidermidis for susceptibility/resistance against commonly prescribed antibiotics. Furthermore, we tested some natural agents alone and in combination with antibiotics to find possible synergistic antimicrobial effects. S. epidermidis clinical isolates were screened for susceptibility/resistance against vancomycin, erythromycin, tetracycline, chloramphenicol, ampicillin, ofloxacin, cephalexin, and gentamicin using the Kirby-Bauer disk diffusion method. The antimicrobial potential of Camellia sinensis, Juglans regia, and Hippophae rhamnoides alone and in combination with antibiotics were examined using the disk diffusion method, where the antimicrobial potential activity was measured in terms of formation of zones of inhibition. Most S. epidermidis isolates were found to be resistant to one or more antibiotics. Gentamycin and ofloxacin were found to be the most effective antibiotics against S. epidermidis isolates. Extracts of Hippophae rhamnoides, Juglans regia, and Camellia sinensis were found to be equally effective against S. epidermidis isolates. In combination with antibiotics, these extracts exhibited appreciable synergistic activity; the highest synergistic activity was observed with erythromycin and cephalexin. In the case of cephalexin, a reversion in resistance was observed. The plant extracts used in the study exhibited additive and synergistic antibacterial activity against S. epidermidis, hence providing an effective alternative to deal with the problem of multidrug resistance.

Antimicrobial properties of single-donor-derived, platelet-leukocyte fibrin for fistula occlusion: An in vitro study.

PubMed

Wu, Xiuwen; Ren, Jianan; Yuan, Yujie; Luan, Jianfeng; Yao, Genhong; Li, Jieshou

2013-01-01

Fibrin glue is a promising alternative for low-output enterocutaneous fistula closure. Bacterial flora colonizing inside the fistula tract, however, may limit the glue application. Single-donor-derived, platelet-rich materials were hypothesized in this study to have antimicrobial activity against Gram-negative microorganisms. Platelet-leukocyte fibrin (PLF), platelet-rich plasma (PRP), and platelet-poor plasma (PPP) were obtained from healthy volunteers. The amounts of platelet, leukocyte, and complement/antibody were determined. In vitro laboratory susceptibility to PLF and plasmas was determined by the Kirby-Bauer disc-diffusion method. Antimicrobial activity of PLF, PRP, and PPP against three Gram-negative ATCC strains was determined in a bacterial kill assay. Levels of complement and antibody did not significantly differ among PLF, PRP, and PPP (p > 0.05), while platelet and leukocyte counts in platelet-rich biomaterials were significantly higher than those in PPP (p < 0.001). The bactericidal effects produced by PLF and PRP were more pronounced than those by PPP in both qualitative and quantitative aspects. No inhibitory zones against three Gram-negative organisms were observed in the Bioseal®. In conclusion, our homemade PLF, as compared with commercial products, had remarkable antimicrobial activity against Gram-negative bacteria relevant to fistula colonization. The presence of platelets and leukocytes may play an important role in bacterial defense. This is the first study to demonstrate the antibacterial properties of single-unit PLF for fistula closure, presenting a new opportunity for glue sealing.

Statistical inference of empirical constituents in partitioned analysis from integral-effect experiments: An application in thermo-mechanical coupling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevens, Garrison N.; Atamturktur, Sez; Brown, D. Andrew

Rapid advancements in parallel computing over the last two decades have enabled simulations of complex, coupled systems through partitioning. In partitioned analysis, independently developed constituent models communicate, representing dependencies between multiple physical phenomena that occur in the full system. Figure 1 schematically demonstrates a coupled system with two constituent models, each resolving different physical behavior. In this figure, the constituent model, denoted as the “consumer,” relies upon some input parameter that is being provided by the constituent model acting as a “feeder”. The role of the feeder model is to map operating conditions (i.e. those that are stimulating the process)more » to consumer inputs, thus providing functional inputs to the consumer model*. Problems arise if the feeder model cannot be built–a challenge that is prevalent for highly complex systems in extreme operational conditions that push the limits of our understanding of underlying physical behavior. Often, these are also the situations where separate-effect experiments isolating the physical phenomena are not available; meaning that experimentally determining the unknown constituent behavior is not possible (Bauer and Holland, 1995; Unal et al., 2013), and that integral-effect experiments that reflect the behavior of the complete system tend to be the only available observations. In this paper, the authors advocate for the usefulness of integral-effect experiments in furthering a model developer’s knowledge of the physics principles governing the system behavior of interest.« less

Salmonella Weltevreden food poisoning in a tea garden of Assam: An outbreak investigation.

PubMed

Saikia, L; Sharma, A; Nath, R; Choudhury, G; Borah, A K

2015-01-01

Salmonella enterica serovar Weltevreden has been a rare cause of acute gastroenteritis occurring worldwide. Here, we report an outbreak of food poisoning in a tea garden. To determine the aetiological agent and risk factors responsible for the outbreak and to take necessary steps for prevention of future outbreaks. Affected area was visited by a team of microbiologists for collecting stool samples/rectal swabs from affected patients. Samples were processed by culture followed by confirmation of the isolates biochemically, automated bacterial identification system, conventional serotyping and molecular typing. Water samples were also processed for detection of faecal contamination. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion technique according to the Clinical Laboratory Standard Institute guidelines. The isolates were confirmed as S. enterica subspecies enterica serovar Weltevreden. They were found sensitive to ampicillin, amoxycillin-clavulanic acid, ciprofloxacin, ofloxacin, norfloxacin, cefotaxime, ceftriaxone, co-trimoxazole and doxycycline. Water samples showed high-level faecal contamination. Source of outbreak was found to be drinking water contaminated with dead livestock. House to house visit was made for early diagnosis and treatment of the cases, awareness campaigning and chlorination of drinking water. This report emphasises the geographical distribution of this organism in Assam. As S. Weltevreden is widely distributed in domestic animals, people should be made aware of immediate reporting of any unusual death among the livestock and their safe disposal which can significantly reduce the incidence of non-typhoidal salmonellosis in the country.

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens.

PubMed

Chauhan, Ritika; Abraham, Jayanthi

2013-07-01

The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

Antimicrobial profile of essential oils extracted from wild versus cultivated Origanum ehrenberjii against enteric bacteria.

PubMed

Barbour, Elie K; Dankar, Samar K; Shaib, Houssam A; Kumosani, Taha; Azhar, Esam; Masaudi, Saad; Iyer, Archana; Harakeh, Steve

2014-10-15

The role of Origanum ehrenberjii against bacteria that cause enteric diseases is well known. Salmonella and Enterococcus cause high rates of enteric infections around the world. The aim of this study was to extract essential oils from cultivated and naturally growing O. ehrenberjii, compare the chemical profiles of the extracts and estimate their antimicrobial efficacy against enteric pathogens. Sixteen compounds were recovered consistently from essential oils extracted from O. ehrenberjii of wild and cultivated origin. The chemical profiles were determined using GC-MS. Safety of the essential oils was determined by observing mortality of chicks after intramuscular administration of the oils. The antimicrobial efficacy of the oils against the enteric pathogens was determined by the Kirby-Bauer Single Disk Diffusion assay. The levels of thymol, carvacrol, para cymene and γ-terpinene were significantly different in the two oils. A significant difference in in vitro antimicrobial activity of the two oils against Salmonella enterica serovar Typhimurium was observed. Intramuscular administration of the two oils in one day-old chicks resulted in significant differences in mortality of 60% vs. 5% (p < 0.05) for wild and cultivated herbs respectively, reflecting the higher safety of the cultivated herb due to the differences in the levels of certain active ingredients. The chemical profile of essential oil of wild vs. cultivated O. ehrenberjii differ significantly at compound level, suggesting the reason for their significant difference in efficacy against Salmonella enterica serovar Typhimurium, and also significant differences in the toxicity of the two oils.

Frequency of colistin and fosfomycin resistance in carbapenem-resistant Enterobacteriaceae from a tertiary care hospital in Karachi.

PubMed

Qamar, Salima; Shaheen, Najma; Shakoor, Sadia; Farooqi, Joveria; Jabeen, Kauser; Hasan, Rumina

2017-01-01

Management of infections with carbapenem-resistant Enterobacteriaceae (CRE) is challenging. In recent times, agents such as colistin and fosfomycin have been used in combination with other antibiotics to treat such infections. In this study, we aim to seek frequency of colistin and fosfomycin resistance in CRE from Pakistan. This study was conducted at clinical laboratories, Aga Khan University Hospital. In total, 251 CRE were included in the study. Colistin minimum inhibitory concentrations (MICs) were performed using broth microdilution (BMD) method and VITEK ® 2 system, whereas fosfomycin susceptibility was performed using Kirby-Bauer method. MIC 50 and MIC 90 were calculated for colistin and agreement between VITEK and BMD was also calculated. Out of 251 strains colistin MIC of ≥4 µg/mL was seen in 40 (15.9%). Of these strains 20 (50%) were Klebsiella pneumoniae . Colistin MIC 50 and MIC 90 were found to be 0.5 and 16 µg/mL, respectively. BMD and VITEK 2 showed 100% categorical agreement. Essential agreement was 88.5% with kappa score 0.733 indicating strong agreement between VITEK and BMD. 31 out of 251 (12.3%) CREs were resistant to fosfomycin. Study shows frequency of colistin and fosfomycin resistance to be 15.9% and 12.3%, respectively. In countries where rate of CREs is high, emerging resistance against these last resort antibiotics is alarming as it leaves clinicians with almost no options to manage such multidrug resistant and extensively drug resistant infections.

Quantitative phenomenological model of the BOLD contrast mechanism

NASA Astrophysics Data System (ADS)

Dickson, John D.; Ash, Tom W. J.; Williams, Guy B.; Sukstanskii, Alexander L.; Ansorge, Richard E.; Yablonskiy, Dmitriy A.

2011-09-01

Different theoretical models of the BOLD contrast mechanism are used for many applications including BOLD quantification (qBOLD) and vessel size imaging, both in health and disease. Each model simplifies the system under consideration, making approximations about the structure of the blood vessel network and diffusion of water molecules through inhomogeneities in the magnetic field created by deoxyhemoglobin-containing blood vessels. In this study, Monte-Carlo methods are used to simulate the BOLD MR signal generated by diffusing water molecules in the presence of long, cylindrical blood vessels. Using these simulations we introduce a new, phenomenological model that is far more accurate over a range of blood oxygenation levels and blood vessel radii than existing models. This model could be used to extract physiological parameters of the blood vessel network from experimental data in BOLD-based experiments. We use our model to establish ranges of validity for the existing analytical models of Yablonskiy and Haacke, Kiselev and Posse, Sukstanskii and Yablonskiy (extended to the case of arbitrary time in the spin echo sequence) and Bauer et al. (extended to the case of randomly oriented cylinders). Although these models are shown to be accurate in the limits of diffusion under which they were derived, none of them is accurate for the whole physiological range of blood vessels radii and blood oxygenation levels. We also show the extent of systematic errors that are introduced due to the approximations of these models when used for BOLD signal quantification.

Antimicrobial susceptibility testing by Australian veterinary diagnostic laboratories.

PubMed

Hardefeldt, L Y; Marenda, M; Crabb, H; Stevenson, M A; Gilkerson, J R; Billman-Jacobe, H; Browning, G F

2018-04-01

The national strategy for tackling antimicrobial resistance highlights the need for antimicrobial stewardship in veterinary practice and for surveillance of antimicrobial susceptibility in veterinary pathogens. Diagnostic laboratories have an important role in facilitating both of these processes, but it is unclear whether data from veterinary diagnostic laboratories are similar enough to allow for compilation and if there is consistent promotion of appropriate antimicrobial use embedded in the approaches of different laboratories to susceptibility testing. A cross-sectional study of antimicrobial susceptibility testing and reporting procedures by Australian veterinary diagnostic laboratories was conducted in 2017 using an online questionnaire. All 18 veterinary diagnostic laboratories in Australia completed the questionnaire. Kirby-Bauer disc diffusion was the method predominantly used for antimicrobial susceptibility testing and was used to evaluate 86% of all isolates, although two different protocols were used across the 18 laboratories (CLSI 15/18, CDS 3/18). Minimum inhibitory concentrations were never reported by 61% of laboratories. Common isolates were consistently reported on across all species, except for gram-negative isolates in pigs, for which there was some variation in the approach to reporting. There was considerable diversity in the panels of antimicrobials used for susceptibility testing on common isolates and no consistency was apparent between laboratories for any bacterial species. We recommend that nationally agreed and consistent antimicrobial panels for routine susceptibility testing should be developed and a uniform set of guidelines should be adopted by veterinary diagnostic laboratories in Australia. © 2018 Australian Veterinary Association.

Determination of integron frequency by a polymerase chain reaction-restriction fragment length polymorphism method in multidrug-resistant Escherichia coli, which causes urinary tract infections.

PubMed

Fallah, Fatemeh; Karimi, Abdollah; Goudarzi, Mehdi; Shiva, Farideh; Navidinia, Masoumeh; Jahromi, Mana Hadipour; Sajadi Nia, Raheleh Sadat

2012-12-01

The purpose of this study was to determine the presence of integrons in Escherichia coli, which cause urinary tract infections, and to define the association between integrons and antimicrobial susceptibility. Susceptibility of 200 isolates from urine samples of patients suffering from urinary tract infections to 13 antibiotics was determined by the Kirby-Bauer disk diffusion method. The existence of class1 and 2 integrons in resistant isolates was assessed by polymerase chain reaction-restriction fragment length polymorphism and sequencing. Antibiotic resistance patterns were observed as follows: amoxicillin 78%, tetracycline 76.1%, co-trimoxazole 67.7%, cephalotin 60%, nalidixic acid 57.4%, chloramphenicol 49%, gentamicin 46.4%, ceftazidim 38.1%, ciprofloxacin 36.2%, nitrofurantoin 33.5%, amikacin 32.1%, norfloxacin 36.1%, and imipenem 27.1%. Of 200 isolates, 155 (77.5%) were multidrug resistant (MDR). The existence of integrons was confirmed in 50.3% of isolates. Three class 1 integron types, aadA2 being the most frequently found, and four class 2 integron types are described. Significant association between resistance to gentamicin, co-trimoxazole, cephalotin, ceftazidim, imipenem, chloramphenicol, and nalidixic acid with the existence of integrons was observed. Multidrug resistance suggests that the strategy for treatment of patients with E.coli infections needs to be revised. Furthermore, it was shown that integrons may be partly responsible for multidrug resistance. Imipenem and norfloxacin were the most effective antibiotics against isolates.

DOE Office of Scientific and Technical Information (OSTI.GOV)

John, Melanie, E-mail: melanie.john@min.uni-muenchen.de; Heuss-Aßbichler, Soraya; Park, So-Hyun

This study presents a new low temperature synthesis method to obtain pure delafossite (Cu{sup 1+}Fe{sup 3+}O{sub 2}) at a temperature of 70 °C within 24 h. For the first time delafossite is synthesized solely by precipitation and subsequent ageing process and without usage of any additives controlling the oxidation state of copper. The synthesized material, called LT-delafossite, consists of pure Cu{sup 1+}Fe{sup 3+}O{sub 2} exclusive of any side products. Rietveld analysis confirms the presence of both 3R (space group (SG): R-3m) and 2H (SG: P6{sub 3}/mmc) polytypes in LT-delafossite. Electron microscopy images show nanometer-sized hexagonal plates with a diameter <500more » nm and a thickness of <30 nm. Measurements of the magnetic susceptibility from 2 K to 350 K in zero-field show one peak ∼18.5 K, which is attributed to an AFM phase transition. Zero-field-cooled magnetization data between −14 T and +14 T at 2 K revealed an s-shape form around the origin having no remanent magnetization. - Highlights: • New process: low temperature synthesis of pure CuFeO{sub 2} nanoparticles. • Synthesis at 70 °C within 24 h solely by precipitation and ageing. • Nanoparticle characterization by XRD, FTIR, SEM, ICP–OES, TEM and Mößbauer. • Special magnetic properties of nano-sized CuFeO{sub 2} synthesized at low temperatures.« less

Statistical inference of empirical constituents in partitioned analysis from integral-effect experiments: An application in thermo-mechanical coupling

DOE PAGES

Stevens, Garrison N.; Atamturktur, Sez; Brown, D. Andrew; ...

2018-04-16

Rapid advancements in parallel computing over the last two decades have enabled simulations of complex, coupled systems through partitioning. In partitioned analysis, independently developed constituent models communicate, representing dependencies between multiple physical phenomena that occur in the full system. Figure 1 schematically demonstrates a coupled system with two constituent models, each resolving different physical behavior. In this figure, the constituent model, denoted as the “consumer,” relies upon some input parameter that is being provided by the constituent model acting as a “feeder”. The role of the feeder model is to map operating conditions (i.e. those that are stimulating the process)more » to consumer inputs, thus providing functional inputs to the consumer model*. Problems arise if the feeder model cannot be built–a challenge that is prevalent for highly complex systems in extreme operational conditions that push the limits of our understanding of underlying physical behavior. Often, these are also the situations where separate-effect experiments isolating the physical phenomena are not available; meaning that experimentally determining the unknown constituent behavior is not possible (Bauer and Holland, 1995; Unal et al., 2013), and that integral-effect experiments that reflect the behavior of the complete system tend to be the only available observations. In this paper, the authors advocate for the usefulness of integral-effect experiments in furthering a model developer’s knowledge of the physics principles governing the system behavior of interest.« less

Microbial contamination of mobile phones in a health care setting in Alexandria, Egypt.

PubMed

Selim, Heba Sayed; Abaza, Amani Farouk

2015-01-01

This study aimed at investigating the microbial contamination of mobile phones in a hospital setting. Swab samples were collected from 40 mobile phones of patients and health care workers at the Alexandria University Students' Hospital. They were tested for their bacterial contamination at the microbiology laboratory of the High Institute of Public Health. Quantification of bacteria was performed using both surface spread and pour plate methods. Isolated bacterial agents were identified using standard microbiological methods. Methicillin-resistant Staphylococcus aureus was identified by disk diffusion method described by Bauer and Kirby. Isolated Gram-negative bacilli were tested for being extended spectrum beta lactamase producers using the double disk diffusion method according to the Clinical and Laboratory Standards Institute recommendations. All of the tested mobile phones (100%) were contaminated with either single or mixed bacterial agents. The most prevalent bacterial contaminants were methicillin-resistant S. aureus and coagulase-negative staphylococci representing 53% and 50%, respectively. The mean bacterial count was 357 CFU/ml, while the median was 13 CFU/ml using the pour plate method. The corresponding figures were 2,192 and 1,720 organisms/phone using the surface spread method. Mobile phones usage in hospital settings poses a risk of transmission of a variety of bacterial agents including multidrug-resistant pathogens as methicillin-resistant S. aureus. The surface spread method is an easy and useful tool for detection and estimation of bacterial contamination of mobile phones.

Microbial contamination of mobile phones in a health care setting in Alexandria, Egypt

PubMed Central

Selim, Heba Sayed; Abaza, Amani Farouk

2015-01-01

Aim: This study aimed at investigating the microbial contamination of mobile phones in a hospital setting. Methods: Swab samples were collected from 40 mobile phones of patients and health care workers at the Alexandria University Students’ Hospital. They were tested for their bacterial contamination at the microbiology laboratory of the High Institute of Public Health. Quantification of bacteria was performed using both surface spread and pour plate methods. Isolated bacterial agents were identified using standard microbiological methods. Methicillin-resistant Staphylococcus aureus was identified by disk diffusion method described by Bauer and Kirby. Isolated Gram-negative bacilli were tested for being extended spectrum beta lactamase producers using the double disk diffusion method according to the Clinical and Laboratory Standards Institute recommendations. Results: All of the tested mobile phones (100%) were contaminated with either single or mixed bacterial agents. The most prevalent bacterial contaminants were methicillin-resistant S. aureus and coagulase-negative staphylococci representing 53% and 50%, respectively. The mean bacterial count was 357 CFU/ml, while the median was 13 CFU/ml using the pour plate method. The corresponding figures were 2,192 and 1,720 organisms/phone using the surface spread method. Conclusions: Mobile phones usage in hospital settings poses a risk of transmission of a variety of bacterial agents including multidrug-resistant pathogens as methicillin-resistant S. aureus. The surface spread method is an easy and useful tool for detection and estimation of bacterial contamination of mobile phones. PMID:25699226

Combined efficacy of biologically synthesized silver nanoparticles and different antibiotics against multidrug-resistant bacteria.

PubMed

Naqvi, Syed Zeeshan Haider; Kiran, Urooj; Ali, Muhammad Ishtiaq; Jamal, Asif; Hameed, Abdul; Ahmed, Safia; Ali, Naeem

2013-01-01

Biological synthesis of nanoparticles is a growing innovative approach that is relatively cheaper and more environmentally friendly than current physicochemical processes. Among various microorganisms, fungi have been found to be comparatively more efficient in the synthesis of nanomaterials. In this research work, extracellular mycosynthesis of silver nanoparticles (AgNPs) was probed by reacting the precursor salt of silver nitrate (AgNO3) with culture filtrate of Aspergillus flavus. Initially, the mycosynthesis was regularly monitored by ultraviolet-visible spectroscopy, which showed AgNP peaks of around 400-470 nm. X-ray diffraction spectra revealed peaks of different intensities with respect to angle of diffractions (2θ) corresponding to varying configurations of AgNPs. Transmission electron micrographs further confirmed the formation of AgNPs in size ranging from 5-30 nm. Combined and individual antibacterial activities of the five conventional antibiotics and AgNPs were investigated against eight different multidrug-resistant bacterial species using the Kirby-Bauer disk-diffusion method. The decreasing order of antibacterial activity (zone of inhibition in mm) of antibiotics, AgNPs, and their conjugates against bacterial group (average) was; ciprofloxacin + AgNPs (23) . imipenem + AgNPs (21) > gentamycin + AgNPs (19) > vancomycin + AgNPs (16) > AgNPs (15) . imipenem (14) > trimethoprim + AgNPs (14) > ciprofloxacin (13) > gentamycin (11) > vancomycin (4) > trimethoprim (0). Overall, the synergistic effect of antibiotics and nanoparticles resulted in a 0.2-7.0 (average, 2.8) fold-area increase in antibacterial activity, which clearly revealed that nanoparticles can be effectively used in combination with antibiotics in order to improve their efficacy against various pathogenic microbes.

High prevalence of multiple-antibiotic-resistant (MAR) Escherichia coli in river bed sediments of the Apies River, South Africa.

PubMed

Abia, Akebe Luther King; Ubomba-Jaswa, Eunice; Momba, Maggy Ndombo Benteke

2015-10-01

This study aimed at investigating the presence of antibiotic-resistant Escherichia coli in river bed sediments of the Apies River, Gauteng, South Africa, in order to better inform health management decisions designed to protect users of the river. Overall, 180 water and sediment samples were collected at 10 sites along the Apies River from January to February 2014. E. coli was enumerated using the Colilert® 18/Quanti-Tray® 2000 (IDEXX). Isolates were purified by streaking on eosin methylene blue agar followed by the indole test. Pure E. coli isolates were tested for resistance to nine antibiotics by the Kirby-Bauer disc diffusion method. Over 98% of the isolates were resistant to at least one of the antibiotics tested. The highest resistance was observed against nitrofurantoin (sediments) and ampicillin (water). Over 80% of all resistant isolates showed multiple antibiotic resistance (resistance to ≥3 antibiotics). The abundance of E. coli in the sediments not only adds to the evidence that sediments are a reservoir for bacteria and possibly other pathogens including antibiotic-resistant bacteria but also suggests that antibiotic-resistant genes could be transferred to pathogens due to the high prevalence of multiple-antibiotic-resistant (MAR) strains of E. coli observed in the sediment. Using untreated water from the Apies River following resuspension for drinking and other household purposes could pose serious health risks for users. Our results suggest that river bed sediments could serve as reservoirs for MAR bacteria including pathogens under different climatic conditions and their analysis could provide information of public health concerns.

Effect of deposition time of sputtering Ag-Cu thin film on mechanical and antimicrobial properties

NASA Astrophysics Data System (ADS)

Purniawan, A.; Hermastuti, R.; Purwaningsih, H.; Atmono, T. M.

2018-04-01

Metallic implants are important components in biomedical treatment. However, post-surgery infection often occurs after installation of implant. The infections are usually treated by antibiotics, but it still causes several secondary problems. As a prevention treatment, the surgical instruments and implants must be in a sterile condition. This action is still not optimal too because the material still can attract the bacteria. From material science point of view, it can be anticipated by developing a type of material which has antibacterial properties or called antimicrobial material. Silver (Ag) and Copper (Cu) have antimicrobial properties to prevent the infection. In this research, the influence of deposition time of Ag-Cu thin film deposition process as antimicrobial material with Physical Vapor Deposition (PVD) RF Sputtering method was analyzed. Deposition time used were for 10, 15 and 20 minutes in Argon gas pressure around 3 x 10-2 mbar in during deposition process. The morphology and surface roughness of Ag-Cu thin film were characterized using SEM and AFM. Based on the results, the deposition time influences the quality morphology that the thin films have good homogeneity and complete structure for longer deposition time. In addition, from roughness measurement results show that increase deposition time decrease the roughness of thin film. Antimicrobial performance was analyzed using Kirby Bauer Test. The results show that all of sample have good antimicrobial inhibition. Adhesion quality was evaluated using Rockwell C Indentation Test. However, the results indicate that the Ag-Cu thin film has low adhesion strength.

Identification of medically relevant Nocardia species with an abbreviated battery of tests.

PubMed

Kiska, Deanna L; Hicks, Karen; Pettit, David J

2002-04-01

Identification of Nocardia to the species level is useful for predicting antimicrobial susceptibility patterns and defining the pathogenicity and geographic distribution of these organisms. We sought to develop an identification method which was accurate, timely, and employed tests which would be readily available in most clinical laboratories. We evaluated the API 20C AUX yeast identification system as well as several biochemical tests and Kirby-Bauer susceptibility patterns for the identification of 75 isolates encompassing the 8 medically relevant Nocardia species. There were few biochemical reactions that were sufficiently unique for species identification; of note, N. nova were positive for arylsulfatase, N. farcinica were positive for opacification of Middlebrook 7H11 agar, and N. brasiliensis and N. pseudobrasiliensis were the only species capable of liquefying gelatin. API 20C sugar assimilation patterns were unique for N. transvalensis, N. asteroides IV, and N. brevicatena. There was overlap among the assimilation patterns for the other species. Species-specific patterns of susceptibility to gentamicin, tobramycin, amikacin, and erythromycin were obtained for N. nova, N. farcinica, and N. brevicatena, while there was overlap among the susceptibility patterns for the other isolates. No single method could identify all Nocardia isolates to the species level; therefore, a combination of methods was necessary. An algorithm utilizing antibiotic susceptibility patterns, citrate utilization, acetamide utilization, and assimilation of inositol and adonitol accurately identified all isolates. The algorithm was expanded to include infrequent drug susceptibility patterns which have been reported in the literature but which were not seen in this study.

[BIODIVERSITY OF ACANTHOCEPHALANS (ACANTHOCEPHALA) IN FRESHWATER FISHES OF ASIATIC SUB-ARCTIC REGION].

PubMed

Atrashkevich, G I; Mikhailova, E I; Orlovskaya, O M; Pospekhov, V V

2016-01-01

The analysis of taxonomical and ecological diversity of acanthocephalans in fishes of Asiatic sub-Arctic region freshwaters, summarizing changes in modern views on species composition, life cycles, and ecology of background groups of these parasites is given. A priority role of studies provided by O. N. Bauer and his scientific school in organization and development of these aspects of acanthocephalology is demonstrated. Special attention is paid to the assessment of acanthocephalan biodiversity of the genus Neoechinorhynchus, the background group of freshwater fish parasites of the Asiatic sub-Arctic region, and an original key for their species is given. The distribution of acanthocephalans of the genus Acanthocephalus in northeastern Asia is analyzed and prospective study of this parasite group, evolutionary associated with freshwater isopods of the genus Asellus as intermediate hosts, is outlined. The absence of documented evidences on intermediate hosts of other background parasites of freshwater fishes in the region, acanthocephalans of the genus Metechinorhynchus, is revealed. It is assumed that subsequent taxonomic revisions based both on morphological and molecular genetic studies are necessary for the reliable revealing of species composition in each genus of the background acanthocephalans from freshwater fishes of Northern Asia. Theoretical significance of the study of acanthocephalan life cycles and revealing their natural intermediate hosts for the reliable estimation of structural and functional organization of their host-parasite systems in different parts of the range is substantiated and the possibility of the distribution of taxonomic conclusions in new territories is analyzed. A brief annotated taxonomical list of freshwater acanthocephalans of the Asiatic sub-Arctic region is given.

Isolation and characterization of Listeria species from rodents in natural environments in China.

PubMed

Wang, Yan; Lu, Liang; Lan, Ruiting; Salazar, Joelle K; Liu, Jingli; Xu, Jianguo; Ye, Changyun

2017-06-07

Listeria is ubiquitous in a variety of environments and can be isolated from a wide range of animal hosts. Rodents are capable of carrying pathogenic bacteria in their intestines, such as Listeria, and can disseminate those pathogens into the natural environment and to where human activity occurs. In this study, we investigated the occurrence and antimicrobial susceptibility of Listeria spp. isolated from wild rodents found in natural environments in China. We collected 341 intestinal fecal samples of rodents from five different regions of China, all representing different rodent habitats. The antimicrobial susceptibility of the Listeria spp. isolates obtained were firstly assessed using the Kirby-Bauer disk diffusion method. Thirty-one samples were positive for Listeria spp., of which 11 were positive for Listeria monocytogenes and seven were positive for Listeria ivanovii. Other species identified include Listeria innocua, Listeria fleischmannii and Listeria floridensis. All Listeria spp. isolates were sensitive to the majority of the antimicrobials tested, but largely resistant to oxacillin (94.1%) and cefuroxime (70.6%). All L. monocytogenes isolates were further characterized by serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). L. monocytogenes strains were grouped into three serotypes, five sequence types and five pulsotypes (PTs) by serotyping, MLST and PFGE, respectively. Almost half of the isolates (five of 11) belonged to serotype 1/2b, ST87 and PT1. This study determined that Listeria is carried in the intestinal tracts of wild rodents from multiple regions at a low rate, filling an epidemiological data gap on Listeria in natural environments in China.

[Antimicrobial resistance in gram negative bacteria isolated from intensive care units of Colombian hospitals, WHONET 2003, 2004 and 2005].

PubMed

Miranda, María Consuelo; Pérez, Federico; Zuluaga, Tania; Olivera, María del Rosario; Correa, Adriana; Reyes, Sandra Lorena; Villegas, Maria Virginia

2006-09-01

Surveillance systems play a key role in the detection and control of bacterial resistance. It is necessary to constantly collect information from all institutions because the mechanisms of bacterial resistance can operate in different ways between countries, cities and even in hospitals in the same area. Therefore local information is important in order to learn about bacterial behaviour and design appropriate interventions for each institution. Between January 2003 and December 2004, the Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM) developed a surveillance project in 10 tertiary hospitals in 6 cities of Colombia. Describe the trends of antibiotic resistance among the isolates of Escherichia coli, Klebsiella pneumoniae, Pseudomona aeruginosa, Acinetobacter baumannii and Enterobacter cloacae, five of the most prevalent nosocomial Gram negative pathogens. The susceptibility tests were performed by automated methods in 9 hospitals and by Kirby Bauer in 1 hospital. Antibiotics with known activity against Gram negatives, according to the Clinical Laboratory Standards Institute guidelines, were selected. The laboratories performed internal and external quality controls. During the study period, the information was downloaded monthly from the databases of each microbiology laboratory and sent to CIDEIM where it was centralized in a database using the system WHONET 5.3. The high resistance rates reported especially for A. baumannii, evidenced the presence of multidrug resistant bacteria in both ICUs and wards at every studied institution. The creation of a national surveillance network to improve our capabilities to detect, follow up, and control the antibiotic resistance in Colombia is urgently needed.

Linearly scaling and almost Hamiltonian dielectric continuum molecular dynamics simulations through fast multipole expansions

NASA Astrophysics Data System (ADS)

Lorenzen, Konstantin; Mathias, Gerald; Tavan, Paul

2015-11-01

Hamiltonian Dielectric Solvent (HADES) is a recent method [S. Bauer et al., J. Chem. Phys. 140, 104103 (2014)] which enables atomistic Hamiltonian molecular dynamics (MD) simulations of peptides and proteins in dielectric solvent continua. Such simulations become rapidly impractical for large proteins, because the computational effort of HADES scales quadratically with the number N of atoms. If one tries to achieve linear scaling by applying a fast multipole method (FMM) to the computation of the HADES electrostatics, the Hamiltonian character (conservation of total energy, linear, and angular momenta) may get lost. Here, we show that the Hamiltonian character of HADES can be almost completely preserved, if the structure-adapted fast multipole method (SAMM) as recently redesigned by Lorenzen et al. [J. Chem. Theory Comput. 10, 3244-3259 (2014)] is suitably extended and is chosen as the FMM module. By this extension, the HADES/SAMM forces become exact gradients of the HADES/SAMM energy. Their translational and rotational invariance then guarantees (within the limits of numerical accuracy) the exact conservation of the linear and angular momenta. Also, the total energy is essentially conserved—up to residual algorithmic noise, which is caused by the periodically repeated SAMM interaction list updates. These updates entail very small temporal discontinuities of the force description, because the employed SAMM approximations represent deliberately balanced compromises between accuracy and efficiency. The energy-gradient corrected version of SAMM can also be applied, of course, to MD simulations of all-atom solvent-solute systems enclosed by periodic boundary conditions. However, as we demonstrate in passing, this choice does not offer any serious advantages.

Antibiotic sensitivity pattern of causative organisms of neonatal septicemia in an urban hospital of Bangladesh.

PubMed

Monjur, Forhad; Rizwan, Farhana; Asaduzzaman, Muhammad; Nasrin, Nishat; Ghosh, Nobo Krishna; Apu, Apurba Sarker; Haque, Fazlul

2010-06-01

The information of the sensitivity pattern of the causative organisms is very important for effective control of septicemia in neonates. To determine the proportion and profile of pathogenic bacteria in the blood cultures of the neonates with clinically suspected septicemia and their susceptibility pattern to antimicrobial agents for developing a unified antibiotic treatment protocol. A cross-sectional retrospective study was conducted over a period of 3 year and 4 months (39 months). The study included 1000 patients admitted in the selected hospital in Bangladesh. Blood samples for culture were taken aseptically before starting antibiotic therapy. Microorganisms were isolated and identified by standard microbiological processes which include colony morphology, Gram stain, and biochemical profiles. Antimicrobial sensitivity patterns were performed by Kirby-Bauer's disc diffusion method against imipenem, ciprofloxacin, ceftazidime, chloramphenicol, netilmicin, gentamicin, ceftriaxone, aztreonam, cefotaxime, cephalexin, and ampicillin. Among the patients, 633 (63.3%) were males and 367 (36.7%) were females. Blood cultures were found positive in 194 (19.4%) neonates. The organisms isolated were Pseudomonas spp. (31.4%), Klebsiella pneumoniae (23.2%), Staphylococcus aureus (12.4%), Escherichia coli (7.2%), Acinatobactor (5.7%), Gram-negative Bacilli (4.1%), Flavobacterium spp. (3.6%), Serratia spp. (5.7%), Citrobacter fruendi (3.1%), Streptococcus species (2.6%), and Enterobacter spp. (1.0%). A majority of the bacterial isolates in neonatal sepsis were found sensitive to imipenem (91.8%) and ciprofloxacin (57.2%) and resistant to commonly used antibiotics, eg. ampicillin (96.4%) and cephalexin (89.2%). The problem can be mitigated by careful selection and prudent use of available antibiotics.

Colonisation of antibiotic resistant bacteria in a cohort of HIV infected children in Ghana.

PubMed

Sampane-Donkor, Eric; Badoe, Ebenezer Vincent; Annan, Jennifer Adoley; Nii-Trebi, Nicholas

2017-01-01

Antibiotic use not only selects for resistance in pathogenic bacteria, but also in commensal flora of exposed individuals. Little is known epidemiologically about antibiotic resistance in relation to people with HIV infection in sub-Saharan Africa. This study investigated the carriage of antibiotic resistant bacteria among HIV infected children at a tertiary hospital in Ghana. One hundred and eighteen HIV positive children were recruited at the Korle-Bu Teaching Hospital in Ghana and nasopharyngeal specimens were collected from them. The specimens were cultured for bacteria, and the isolates were identified by standard microbiological methods. Antibiotic susceptibility tests were carried out on selected bacterial organisms by the Kirby Bauer method. Bacteria isolated from the study subjects included Moraxella catarrhalis (39.8%), coagulase negative staphylococci (33.1%), Streptococcus pneumoniae (30.5%), diptheroids (29.7%), viridian streptococci (27.1%), Staphylococcus aureus (22.0%), Citrobacter spp. (4.2%) and Neisseria meningitidis (0.9%). Prevalence of antibiotic resistance of S. pneumoniae ranged from 5.6% (ceftriaxone) to 58.3% (cotrimoxazole), M. catarrhalis ranged from 2.1% (gentamicin) to 80.6% (ampicillin), and S. aureus ranged from 7.7% (cefoxitin) to 100% (penicillin). The prevalence of multiple drug resistance was 16.7% for S. pneumoniae, 57.4% for M. catarrhalis and 84.6% for S. aureus. HIV infected children in the study area commonly carry multi-drug resistant isolates of several pathogenic bacteria such as S. aureus and S. pneumoniae. Infections arising in these patients that are caused by S. aureus and S. pneumoniae could be treated with ceftriaxone and cefoxitin respectively.

VizieR Online Data Catalog: NuSTAR serendipitous survey: the 40-month catalog (Lansbury+, 2017)

NASA Astrophysics Data System (ADS)

Lansbury, G. B.; Stern, D.; Aird, J.; Alexander, D. M.; Fuentes, C.; Harrison, F. A.; Treister, E.; Bauer, F. E.; Tomsick, J. A.; Balokovic, M.; Del Moro, A.; Gandhi, P.; Ajello, M.; Annuar, A.; Ballantyne, D. R.; Boggs, S. E.; Brandt, W. N.; Brightman, M.; Chen, C.-T. J.; Christensen, F. E.; Civano, F.; Comastri, A.; Craig, W. W.; Forster, K.; Grefenstette, B. W.; Hailey, C. J.; Hickox, R. C.; Jiang, B.; Jun, H. D.; Koss, M.; Marchesi, S.; Melo, A. D.; Mullaney, J. R.; Noirot, G.; Schulze, S.; Walton, D. J.; Zappacosta, L.; Zhang, W. W.

2017-09-01

Over the period from 2012 July to 2015 November, which is the focus of the current study, there are 510 individual NuSTAR exposures that have been incorporated into the serendipitous survey. These exposures were performed over 331 unique fields (i.e., 331 individual sky regions, each with contiguous coverage composed of one or more NuSTAR exposures), yielding a total sky area coverage of 13deg2. Table 1 lists the fields chronologically. The fields have a cumulative exposure time of 20.4Ms. We have undertaken a campaign of dedicated spectroscopic follow-up in the optical-IR bands, obtaining spectroscopic identifications for a large fraction (56%) of the total sample. Since NuSTAR performs science pointings across the whole sky, a successful ground-based follow-up campaign requires the use of observatories at a range of geographic latitudes, and preferably across a range of dates throughout the sidereal year. This has been achieved through observing programs with, primarily, the following telescopes over a multiyear period (2012 Oct 10 to 2016 Jul 10): the Hale Telescope at Palomar Observatory (5.1m; PIs F. A. Harrison and D. Stern); Keck I and II at the W. M. Keck Observatory (10m; PIs F. A. Harrison and D. Stern); the New Technology Telescope (NTT) at La Silla Observatory (3.6m; PI G. B. Lansbury); the Magellan I (Baade) and Magellan II (Clay) Telescopes at Las Campanas Observatory (6.5m; PIs E. Treister and F. E. Bauer); and the Gemini-South observatory (8.1m; PI E. Treister). (5 data files).

Isolation and characterization of Listeria species from rodents in natural environments in China

PubMed Central

Wang, Yan; Lu, Liang; Lan, Ruiting; Salazar, Joelle K; Liu, Jingli; Xu, Jianguo; Ye, Changyun

2017-01-01

Listeria is ubiquitous in a variety of environments and can be isolated from a wide range of animal hosts. Rodents are capable of carrying pathogenic bacteria in their intestines, such as Listeria, and can disseminate those pathogens into the natural environment and to where human activity occurs. In this study, we investigated the occurrence and antimicrobial susceptibility of Listeria spp. isolated from wild rodents found in natural environments in China. We collected 341 intestinal fecal samples of rodents from five different regions of China, all representing different rodent habitats. The antimicrobial susceptibility of the Listeria spp. isolates obtained were firstly assessed using the Kirby–Bauer disk diffusion method. Thirty-one samples were positive for Listeria spp., of which 11 were positive for Listeria monocytogenes and seven were positive for Listeria ivanovii. Other species identified include Listeria innocua, Listeria fleischmannii and Listeria floridensis. All Listeria spp. isolates were sensitive to the majority of the antimicrobials tested, but largely resistant to oxacillin (94.1%) and cefuroxime (70.6%). All L. monocytogenes isolates were further characterized by serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). L. monocytogenes strains were grouped into three serotypes, five sequence types and five pulsotypes (PTs) by serotyping, MLST and PFGE, respectively. Almost half of the isolates (five of 11) belonged to serotype 1/2b, ST87 and PT1. This study determined that Listeria is carried in the intestinal tracts of wild rodents from multiple regions at a low rate, filling an epidemiological data gap on Listeria in natural environments in China. PMID:28588285

Virulence Factors of Staphylococcus aureus Isolates in an Iranian Referral Children's Hospital.

PubMed

Sabouni, Farah; Mahmoudi, Shima; Bahador, Abbas; Pourakbari, Babak; Sadeghi, Reihaneh Hosseinpour; Ashtiani, Mohammad Taghi Haghi; Nikmanesh, Bahram; Mamishi, Setareh

2014-04-01

The clinical importance of Staphylococcus aureus (S. aureus) is attributed to notable virulence factors, surface proteins, toxins, and enzymes as well as the rapid development of drug resistance. The aim of this study was to compare the occurrence of virulence factors produced by S. aureus strains isolated from children in an Iranian referral children's hospital. The presence of genes encoding for the enterotoxins A (sea), B (seb), C (sec), D (sed), TSST-1 (tsst), exfoliative toxin A (eta), and exfoliative toxin B (etb) were detected by Multiplex polymerase chain reaction (PCR) using specific primers. In addition, the standardized Kirby-Bauer disc-diffusion method was performed on Mueller-Hinton agar. In total, 133 S. aureus isolates were obtained from different patients. Of these S. aureus isolates, 64 (48%) were methicillin-resistant S. aureus (MRSA), and all of these tested positive for the mecA gene. Regarding the classical enterotoxin genes, sea gene (40.6%) was the most prevalent followed by seb (19.6%), tsst (12.8%), eta (11.3%), etb (9%), sed (4.5%), and sec (3%). Among methicillin-susceptible S. aureus (MSSA) isolates, seb and tsst were the more prevalent toxins in comparison with MRSA isolates (p < 0.05), while the frequency of sea, sed, eta, and etb genes were higher among MRSA isolates (p > 0.05). In our study enterotoxin A was produced by 40.6% of the isolates (48% from MRSA and 33% from MSSA isolates) which was higher than in previous reports. According to our results, strict hygiene and preventative measures during food processing are highly recommended.

Tensile Properties of Hydrogels and of Snake Skin

NASA Technical Reports Server (NTRS)

Hinkley, Jeffrey A.; Savitzky, Alan H.; Rivera, Gabriel; Gehrke, Stevin H.

2002-01-01

Stimulus-responsive or 'smart' gels are of potential interest as sensors and actuators, in industrial separations, and as permeable delivery systems. In most applications, a certain degree of mechanical strength and toughness will be required, yet the large-strain behavior of gels has not been widely reported. Some exceptions include work on gelatin and other food gels, some characterization of soft gels applicable for in-vitro cell growth studies, and toughness determinations on commercial contact lens materials. In general, it can be anticipated that the gel stiffness will increase with increasing degree of crosslinking, but the tensile strength may go through a maximum. Gel properties can be tailored by varying not only the degree of crosslinking, but also the polymer concentration and the nature of the polymer backbone (e.g. its stiffness or solubility). Polypeptides provide an especially interesting case, where secondary structure affects trends in moduli and conformational transitions may accompany phase changes. A few papers on the tensile properties of responsive gels have begun to appear. The responsive hydrogel chosen for the present study, crosslinked hydroxypropylcellulose, shrinks over a rather narrow temperature range near 44 C. Some vertebrate skin is also subject to substantial strain. Among reptiles, the morphologies of the skin and scales show wide variations. Bauer et al. described the mechanical properties and histology of gecko skin; longitudinal tensile properties of snake skin were examined by Jayne with reference to locomotion. The present measurements focus on adaptations related to feeding, including the response of the skin to circumferential tension. Tensile properties will be related to interspecific and regional variation in skin structure and folding.

Relationship between drug resistance and the clustered, regularly interspaced, short, palindromic repeat-associated protein genes cas1 and cas2 in Shigella from giant panda dung.

PubMed

Ren, Lu; Deng, Lin-Hua; Zhang, Ri-Peng; Wang, Cheng-Dong; Li, De-Sheng; Xi, Li-Xin; Chen, Zhen-Rong; Yang, Rui; Huang, Jie; Zeng, Yang-Ru; Wu, Hong-Lin; Cao, San-Jie; Wu, Rui; Huang, Yong; Yan, Qi-Gui

2017-02-01

To detect drug resistance in Shigella obtained from the dung of the giant panda, explore the factors leading to drug resistance in Shigella, understand the characteristics of clustered, regularly interspaced, short, palindromic repeats (CRISPR), and assess the relationship between CRISPR and drug resistance. We collected fresh feces from 27 healthy giant pandas in the Giant Panda Conservation base (Wolong, China). We identified the strains of Shigella in the samples by using nucleotide sequence analysis. Further, the Kirby-Bauer paper method was used to determine drug sensitivity of the Shigella strains. CRISPR-associated protein genes cas1 and cas2 in Shigella were detected by polymerase chain reaction (PCR), and the PCR products were sequenced and compared. We isolated and identified 17 strains of Shigella from 27 samples, including 14 strains of Shigella flexneri, 2 strains of Shigella sonnei, and 1 strain of Shigella dysenteriae. Further, drug resistance to cefazolin, imipenem, and amoxicillin-clavulanic acid was identified as a serious problem, as multidrug-resistant strains were detected. Further, cas1 and cas2 showed different degrees of point mutations. The CRISPR system widely exists in Shigella and shares homology with that in Escherichia coli. The cas1 and cas 2 mutations contribute to the different levels of resistance. Point mutations at sites 3176455, 3176590, and 3176465 in cas1 (a); sites 3176989, 3176992, and 3176995 in cas1 (b); sites 3176156 and 3176236 in cas2 may affect the resistance of bacteria, cause emergence of multidrug resistance, and increase the types of drug resistance.

Ergosterol, arabitol and mannitol as tracers for biogenic aerosols in the Eastern Mediterranean

NASA Astrophysics Data System (ADS)

Burshtein, N.; Yona, N. Lang; Rudich, Y.

2010-11-01

Aerosols containing biological components can have a significant effect on human health by causing primarily irritation, infection and allergies. Specifically, airborne fungi can cause a wide array of adverse responses in humans depending on the type and quantity present. In this study we used chemical biomarkers for analyzing fungi-containing aerosols in the eastern Mediterranean region during the year 2009 in order to quantify annual fungal abundances. The prime marker for fungi used in this study was ergosterol, and its concentrations were compared with those of mannitol and arabitol, which were recently suggested to also correlate with fungal spores concentrations (Bauer et al., 2008a). Back trajectory analysis, inorganic ions, humidity and temperature were used in an attempt to identify sources as well as the dependence on seasonal and environmental conditions. We found that the ambient concentrations of ergosterol, arabitol and mannitol range between 0 and 2.73 ng m-3, 1.85 and 58.27 ng m-3, 5.57 and 138.03 ng m-3, respectively. The highest levels for all biomarkers were during the autumn, probably from local terrestrial sources, as deduced from the inorganic ions and back trajectory analysis. Significant correlations were observed between arabitol and mannitol during the entire year except for the winter months. Both sugars correlated with ergosterol only during the spring and autumn. We conclude that mannitol and arabitol might not be specific biomarkers for fungi and that the observed correlations during spring and autumn may be attributed to high levels of vegetation during spring blossoms and autumn decomposition.

Ergosterol, arabitol and mannitol as tracers for biogenic aerosols in the eastern Mediterranean

NASA Astrophysics Data System (ADS)

Burshtein, N.; Lang-Yona, N.; Rudich, Y.

2011-01-01

Aerosols containing biological components can have a significant effect on human health by causing primarily irritation, infection and allergies. Specifically, airborne fungi can cause a wide array of adverse responses in humans depending on the type and quantity present. In this study we used chemical biomarkers for analyzing fungi-containing aerosols in the eastern Mediterranean region during the year 2009 in order to quantify annual fungal abundances. The prime marker for fungi used in this study was ergosterol, and its concentrations were compared with those of mannitol and arabitol which were recently suggested to also correlate with fungal spores concentrations (Bauer et al., 2008a). Back trajectory analysis, inorganic ions, humidity and temperature were used in an attempt to identify sources as well as the dependence on seasonal and environmental conditions. We found that the ambient concentrations of ergosterol, arabitol and mannitol range between 0 and 2.73 ng m-3, 1.85 and 58.27 ng m-3, 5.57 and 138.03 ng m-3, respectively. The highest levels for all biomarkers were during the autumn, probably from local terrestrial sources, as deduced from the inorganic ions and back trajectory analysis. Significant correlations were observed between arabitol and mannitol during the entire year except for the winter months. Both sugars correlated with ergosterol only during the spring and autumn. We conclude that mannitol and arabitol might not be specific biomarkers for fungi and that the observed correlations during spring and autumn may be attributed to high levels of vegetation during spring blossoms and autumn decomposing.

Detection of Metallo-Beta Lactamases Among Carbapenem-Resistant Pseudomonas aeruginosa.

PubMed

Farajzadeh Sheikh, Ahmad; Rostami, Soodabeh; Jolodar, Abbas; Tabatabaiefar, Mohammad Amin; Khorvash, Farzin; Saki, Azadeh; Shoja, Saeed; Sheikhi, Raheleh

2014-11-01

Carbapenems are important drugs used for the treatment of Pseudomonas aeruginosa infections, however metallo-β-lactamases (MBL) are able to efficiently hydrolyze these classes of drugs. Immediate detection of the MBL-producing P. aeruginosa is necessary in order to accurately treat infections caused by this organism. To determine the prevalence of MBL producing P. aeruginosa in burn and non-burn patients by two phenotypic tests and polymerase chain reaction (PCR) and to compare phenotypic tests with PCR. A total of 223 non-duplicate strains of P. aeruginosa were collected from three teaching hospitals of Ahvaz, Iran. Antimicrobial susceptibility and minimum inhibitory concentrations (MICs) of carbapenems (imipenem, meropenem, doripenem and ertapenem) were determined by the Kirby-Bauer and E-test methods. Combined disk (CD) test, MBL E-test and PCR were performed for carbapenem-resistant P. aeruginosa isolates. Amongst all the P. aeruginosa isolates, 58.7% were resistant to imipenem while 31.8%, 13.5% and 74.4% were resistant to meropenem, doripenem and ertapenem, respectively. Amongst all the P. aeruginosa isolates, 44.4% were multidrug resistant and 13.45% were resistant to all of the carbapenems. The CD test with doripenem disk / 750 μg ethylene diamine tetra acetic acid (EDTA) had the highest efficiency compared to the other phenotypic tests. bla IMP and bla VIM genes were detected in 11.7% and 0.4% of isolates, respectively. bla SPM and bla NDM genes were not observed. Epidemiological and regional evaluation of MBL-producing P. aeruginosa through simple and inexpensive methods should be considered for effective treatment of carbapenem-resistant P. aeruginosa infections.

Identification and characterization of metallo-β-lactamases producing Pseudomonas aeruginosa clinical isolates in University Hospital from Zanjan Province, Iran.

PubMed

Doosti, Masoumeh; Ramazani, Ali; Garshasbi, Maryam

2013-01-01

Infectious by Pseudomonas aeruginosa has spread worldwide and metallo-beta-lactamases (MBL) are being reported with increasing frequency. The aim of this study was to investigate the antibiotic susceptibility and distribution of blaVIM and blaIMP genes in P. aeruginosa isolates from Zanjan Province of Iran. A total of 70 P. aeruginosa isolates were identified from patients admitted at intensive care units. The antimicrobial susceptibility was tested by disk diffusion (Kirby-Bauer) method and for production of MBL using double-disk synergy test (DDST). After DNA extraction, the presence of blaVIM and blaIMP genes and class 1 integron were detected by PCR. Most of the isolates were resistant to meropenem, cefotaxime and imipenem (IPM). Also, 44/70 (62.85%) IPM resistant isolates were confirmed by DDST. Of the 44 clinical isolates, 41 (93%) isolates showed MIC≥4 µg/ml for IPM. Based on the DDST results, 36 (87.8%) were confirmed to be MBL producers. PCR amplification showed that 23/41 (56%) carried blaVIM and 10/41 (24.3%) possessed blaIMP gene. Also, 31/44 (70.5%) isolates contained class 1 integron gene. Our results highlight that the genes for Verona integron-encoded metallo-β-lactamase, IPM β-lactamases and class 1 integrons were predominantly present among the IPM-resistant P. aeruginosa tested in our province and also the frequency of blaVIM type is higher than blaIMP. This is the first report of P. aeruginosa strains producing blaIMP with high frequency from Zanjan province of Iran.

Bacteriocin from Bacillus subtilis as a novel drug against diabetic foot ulcer bacterial pathogens

PubMed Central

Joseph, Baby; Dhas, Berlina; Hena, Vimalin; Raj, Justin

2013-01-01

Objective To isolate and identify Bacillus subtilis (B. subtilis) from soil and to characterize and partially purify the bacteriocin. To evaluate the antimicrobial activity against four diabetic foot ulcer bacterial pathogens. Methods Genotypic identification was done based on Bergey's manual of systemic bacteriology. Antimicrobial susceptibility test was done by Kirby-Bauer disc diffusion method. Colonies were identified by colony morphology and biochemical characterization and also compared with MTCC 121 strain. Further identification was done by 16S rRNA sequencing. Inhibitory activities of partially purified bacteriocin on all the DFU isolates were done by agar well diffusion method. The strain was identified to produce bacteriocin by stab overlay assay. Bacteriocin was extracted by organic solvent extraction using chloroform, further purified by HPLC and physical, and chemical characterization was performed. Results The four isolates showed high level of resistance to amoxyclav and sensitivity to ciprofloxacin. HPLC purification revealed that the extracts are bacteriocin. The phylogenetic tree analysis results showed that the isolate was 99% related to B. subtilis BSF01. The results reveled activity to all the four isolates and high level of activity was seen in case of Klebsiella sp. Conclusions Partially purified bacteriocin was found to have antimicrobial activity against the four diabetic foot ulcer bacterial pathogens, which can thus be applied as a better drug molecule on further studies. The strain B. subtilis are found to be safe for use and these antimicrobial peptides can be used as an antimicrobial in humans to treat DFU bacterial pathogens. PMID:24093784

Bacteriocin from Bacillus subtilis as a novel drug against diabetic foot ulcer bacterial pathogens.

PubMed

Joseph, Baby; Dhas, Berlina; Hena, Vimalin; Raj, Justin

2013-12-01

To isolate and identify Bacillus subtilis (B. subtilis) from soil and to characterize and partially purify the bacteriocin. To evaluate the antimicrobial activity against four diabetic foot ulcer bacterial pathogens. Genotypic identification was done based on Bergey's manual of systemic bacteriology. Antimicrobial susceptibility test was done by Kirby-Bauer disc diffusion method. Colonies were identified by colony morphology and biochemical characterization and also compared with MTCC 121 strain. Further identification was done by 16S rRNA sequencing. Inhibitory activities of partially purified bacteriocin on all the DFU isolates were done by agar well diffusion method. The strain was identified to produce bacteriocin by stab overlay assay. Bacteriocin was extracted by organic solvent extraction using chloroform, further purified by HPLC and physical, and chemical characterization was performed. The four isolates showed high level of resistance to amoxyclav and sensitivity to ciprofloxacin. HPLC purification revealed that the extracts are bacteriocin. The phylogenetic tree analysis results showed that the isolate was 99% related to B. subtilis BSF01. The results reveled activity to all the four isolates and high level of activity was seen in case of Klebsiella sp. Partially purified bacteriocin was found to have antimicrobial activity against the four diabetic foot ulcer bacterial pathogens, which can thus be applied as a better drug molecule on further studies. The strain B. subtilis are found to be safe for use and these antimicrobial peptides can be used as an antimicrobial in humans to treat DFU bacterial pathogens. Copyright © 2013 Asian Pacific Tropical Biomedical Magazine. Published by Elsevier B.V. All rights reserved.

The Antifungal Inhibitory Concentration Effectiveness Test From Ethanol Seed Arabica Coffee (Coffea arabica) Extract Against The Growth Of Candida albicans Patient Isolate With In Vitro Method

NASA Astrophysics Data System (ADS)

Satria Rakatama, Adam; Pramono, Andri; Yulianti, Retno

2018-03-01

Candida albicans are the most frequent cause of Vulvovaginalis Candidiasis infection. Its treatment using antifungal drugs, are oftenly caused side effects. The reduction of C.albicans growth and the reduction of antifungal drugs side effect, were our main purposed. Our study objective is determine the effectiveness of inhibitory power of arabica coffee seed ethanol extract on the growth of C.albicans patient isolates. The type of this research is experimental research. Kirby-bauer method with the Saboraud Dextrose Agar (SDA) media was used in this experiment. Inhibitory zone was observed around the disc, to determine the inhibitory power. The results showed that the inhibitory zone was formed on arabica coffee seed ethanol extract on 10%, 20%, 40%, and 80% concentration. Kruskal-Wallis test results (p<0,05) showed that there was a significant difference in mean between the concentration groups tested against the treatment group. The inhibitory zone was formed because of biochemical compound in arabica coffee seed such as caffeine, phenol, alkaloids, flavonoids, and saponins. Inhibitory zone in C.albicans patient isolates were smaller compared with C.albicans ATCC 90028 as gold standard. This showed that the virulence of C.albicans from patients isolates were higher. We concluded that arabica coffee seed ethanol extract could inhibiting the growth of C.albicans patient isolates. Optimization of coffee seed ethanol extract to obtain maximum active ingredients still needs to be done. This knowledge is expected to be used for the beginning manufacturer antifungal drug from natural product.

[Asymptomatic bacteruiria frequency in pregnant women and uropathogen in vitro antimicrobial sensitivity].

PubMed

Hernández Blas, Fernanda; López Carmona, Juan Manuel; Rodríguez Moctezuma, José Raymundo; Peralta Pedrero, María Luisa; Rodríguez Gutiérrez, Román Salvador; Ortiz Aguirre, Alma Rosa

2007-06-01

To estimate the frequency of asymptomatic bacteriuria in pregnant women attended in Family Medicine Units of the Instituto Mexicano del Seguro Social and to determine the in vitro sensitivity rate of the microorganisms to ampicillin, trimethoprim-sulfamethoxazole, nitrofurantoin and amikacin. We carried out an observational, prospective and transversal study at Family Medicine Units 62 and 64 of the Mexico State Delegation, located in the urban area of Mexico City. Women with lesser than 32 weeks of pregnancy without urinary tract symptoms were included. Urine culture of a midstream urine specimen with > or = 10(5) colony forming units/mL urine of an only germen was used as the gold standard. The in vitro antimicrobial sensitivity was established according to the Bauer Kirby technique. 874 pregnant women were included and 73 had a positive urine culture, with a frequency of 8.4%, IC 95% = 6.6 - 10.2%, of asymptomatic bacteriuria. Escherichia coil was the most frequent isolated agent (77%). In vitro sensitivity to ampicillin of the microorganisms isolated was of 27%, IC 95% = 16 - 38%; to trimethoprim-sulfamethoxazole of 40%, IC95% = 29 - 51%; to amikacin of 68%, IC 95% = 57 - 79%, and to nitrofurantoin of 79%, IC 95% = 70 - 88%. The frequency of asymptomatic bacteriuria in the studied population is similar to the reported by the literature. The in vitro sensitivity rates of E. coil to ampicillin and to trimethoprim-sulfamethoxazole are very low. The best sensitivity corresponded to the nitrofurantoin. The treatment of the asymptomatic bacteriuria must be based on the local patterns of antimicrobial sensitivity and resistance.

Analysis of Four Scoring Systems for the Prognosis of Patients with Metastasis of the Vertebral Column.

PubMed

Pollner, Péter; Horváth, Anna; Mezei, Tamás; Banczerowski, Péter; Czigléczki, Gábor

2018-04-01

Metastatic spinal diseases are common health problems and there is no consensus on the appropriate treatment of metastases in several conditions. Using clinical measures (e.g., survival time and functional status), prognosis prediction systems advise on the appropriate interventions. The aim of this article is to assess and compare 4 widely used scoring systems (revised Tokuhashi, Tomita, van der Linden, and modified Bauer scores) on a single-center cohort. A retrospective study was designed of 329 patients who were subjected to surgery because of metastatic spinal diseases. Subpopulations according to the classifications of the 4 scoring systems were identified. The overall survival was calculated with the Kaplan-Meier formula. The difference between the survival curves of subpopulations was analyzed with log-rank tests. The consistency rates for the 4 scoring systems are calculated as well. The follow-up period was 8 years. The median survival time was 222 days. The overall survival of prognostic categories in 3 scoring systems was significantly different from each other, but we found no differences between the categories of the van der Linden system. In this cohort, the revised Tokuhashi system gave the best approximation for survival, with a mean predictive capability 60.5%. The evaluation of 4 standard scoring systems showed that 3 were self-consistent, although none of systems was able to predict the survival in our cohort. Based on the predictive capability, the revised Tokuhashi system may provide the best predictions with careful examination of individual cases. Copyright © 2018 Elsevier Inc. All rights reserved.

Colonisation of antibiotic resistant bacteria in a cohort of HIV infected children in Ghana

PubMed Central

Sampane-Donkor, Eric; Badoe, Ebenezer Vincent; Annan, Jennifer Adoley; Nii-Trebi, Nicholas

2017-01-01

Antibiotic use not only selects for resistance in pathogenic bacteria, but also in commensal flora of exposed individuals. Little is known epidemiologically about antibiotic resistance in relation to people with HIV infection in sub-Saharan Africa. This study investigated the carriage of antibiotic resistant bacteria among HIV infected children at a tertiary hospital in Ghana. One hundred and eighteen HIV positive children were recruited at the Korle-Bu Teaching Hospital in Ghana and nasopharyngeal specimens were collected from them. The specimens were cultured for bacteria, and the isolates were identified by standard microbiological methods. Antibiotic susceptibility tests were carried out on selected bacterial organisms by the Kirby Bauer method. Bacteria isolated from the study subjects included Moraxella catarrhalis (39.8%), coagulase negative staphylococci (33.1%), Streptococcus pneumoniae (30.5%), diptheroids (29.7%), viridian streptococci (27.1%), Staphylococcus aureus (22.0%), Citrobacter spp. (4.2%) and Neisseria meningitidis (0.9%). Prevalence of antibiotic resistance of S. pneumoniae ranged from 5.6% (ceftriaxone) to 58.3% (cotrimoxazole), M. catarrhalis ranged from 2.1% (gentamicin) to 80.6% (ampicillin), and S. aureus ranged from 7.7% (cefoxitin) to 100% (penicillin). The prevalence of multiple drug resistance was 16.7% for S. pneumoniae, 57.4% for M. catarrhalis and 84.6% for S. aureus. HIV infected children in the study area commonly carry multi-drug resistant isolates of several pathogenic bacteria such as S. aureus and S. pneumoniae. Infections arising in these patients that are caused by S. aureus and S. pneumoniae could be treated with ceftriaxone and cefoxitin respectively. PMID:28451037

Genetic Investigation of Beta-Lactam Associated Antibiotic Resistance Among Escherichia Coli Strains Isolated from Water Sources.

PubMed

Ranjbar, Reza; Sami, Mehrdad

2017-01-01

Antimicrobial resistance is an important factor threatening human health. It is widely accepted that antibiotic resistant bacteria such as Escherichia coli ( E. coli) released from humans and animals into the water sources, can introduce their resistance genes into the natural bacterial community. The aim of this study was to investigate the prevalence of bla TEM , bla CTX , bla SHV , bla OXA and bla VEB associated-antibiotic resistance among E. coli bacteria isolated from different water resources in Iran. The study contained all E. coli strains segregated from different surface water sources. The Kirby-Bauer method and combined discs method was determined in this study for testing antimicrobial susceptibility and strains that produced Extended-Spectrum Beta Lactamases (ESBL), respectively. DNA extraction kit was applied for genomic and plasmid DNA derivation. Finally the frequency of resistant genes including bla TEM , bla CTX , bla SHV , bla OXA and bla VEB in ESBL producing isolates were studied by PCR. One hundred E. coli strains were isolated and entered in the study. The highest antibiotic resistance was observed on clindamycin (96%). Moreover, 38.5% isolates were ESBL producers. The frequency of different ESBLs genes were 37%, 27%, 27%, and 25% for bla TEM , bla CTX , bla SHV , and bla OXA , respectively. The bla VEB wasn't found in any isolates. The study revealed a high prevalence of CTX-M, TEM, SHV and OXA genes among E. coli strains in surface water resources. In conclusion, these results raised a concern regarding the presence and distribution of these threatening factors in surface water sources and its subsequent outcomes.

An iron( ii ) hydride complex of a ligand with two adjacent β-diketiminate binding sites and its reactivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gehring, Henrike; Metzinger, Ramona; Braun, Beatrice

2016-01-13

After lithiation of PYR-H2 (PYR = [(NC(Me)C(H)C(Me)NC6H3(iPr)2)2(C5H3N)]2-) – the precursor of an expanded β-diketiminato ligand system with two binding pockets – with KN(TMS)2 the reaction of the resulting potassium salt with FeBr2 led to a dinuclear iron(II) bromide complex [(PYR)Fe(μ-Br)2Fe] (1). Through treatment with KHBEt3 the bromide ligands could be replaced by hydrides to yield [PYR)Fe2(μ-H)2] (2), a distorted analogue of known β-diketiminato iron hydride complexes, as evidenced by NMR, Mößbauer and X-ray absorption spectroscopy, as well as by its reactivity: for instance, 2 reacts with the proton source lutidinium triflate via protonation of the hydride ligands to form anmore » iron(II) product [(PYR)Fe2(OTf)2] (4), while CO2 inserts into the Fe–H bonds generating the formate complex [(PYR)Fe2(μ-HCOO)2] (5); in the presence of traces of water partial hydrolysis occurs so that [(PYR)Fe2(μ-OH)(μ-HCOO)] (6) is isolated. Altogether, the iron(II) chemistry supported by the PYR2- ligand is distinctly different from the one of nickel(II), where both, the arrangement of the two binding pockets and the additional pyridyl donor led to diverging features as compared with the corresponding system based on the parent β-diketiminato ligand.« less

Isolation and identification of local bacteria endophyte and screening of its antimicrobial property against pathogenic bacteria and fungi

NASA Astrophysics Data System (ADS)

Fikri, Ahmad Syairazie Ibrahim; Rahman, Irman Abdul; Nor, Norefrina Shafinaz Md; Hamzah, Ainon

2018-04-01

Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

The draft genomes and investigation of serotype distribution, antimicrobial resistance of group B Streptococcus strains isolated from urine in Suzhou, China.

PubMed

Guo, Yong; Deng, Xiao; Liang, Yuan; Zhang, Liang; Zhao, Guo-Ping; Zhou, Yan

2018-06-26

The group B Streptococcus (GBS) is a human commensal bacterium, which is capable of causing several infectious diseases in infants, and people with chronic diseases. GBS has been the most common cause of infections in urinary tract of the elders, but relatively few studies reported the urine-isolated GBS and their antimicrobial susceptibilities. Hence, we decided to investigate GBS specially isolated from urine in Suzhou, China. 27 GBS samples were isolated from urine in Suzhou, China. The PCR and agarose gel electrophoresis were used to identify the serotype distribution. Susceptibility tests were based on MIC test and Kirby-Bauer test. Genome were sequenced via Illumina Hiseq platform and assembled by SPAdes. Genomes of five isolates were sequenced and submitted to NCBI genome database. The sequencing files in fastq format were submitted to NCBI SRA database. Five serotypes were identified. The resistant rates measured for tetracycline, erythromycin, clindamycin and fluoroquinolones were 74.1, 63.0, 44.4 and 48.1%, respectively. 18.5% of the isolates were nonsusceptible to nitrofurantoin. The resistance to tetracycline was mainly associated with the gene tetM. The erythromycin resistance was mainly associated with the genes ermB and mefE. The genes ermB and lnuB were the prevalent genes in cMLSB type. No known nitrofurantoin resistance gene was found in nitrofurantoin-nonsusceptible GBS. Five serotypes were identified in our study. High rates of GBS isolates were resistant to tetracycline, erythromycin, clindamycin and fluoroquinolones. The genes ermB and lnuB occupied high rates in cMLS B phenotype.

Escherichia coli Overexpressing a Baeyer-Villiger Monooxygenase from Acinetobacter radioresistens Becomes Resistant to Imipenem

PubMed Central

Minerdi, Daniela; Zgrablic, Ivan; Castrignanò, Silvia; Catucci, Gianluca; Medana, Claudio; Terlizzi, Maria Elena; Gribaudo, Giorgio; Gilardi, Gianfranco

2015-01-01

Antimicrobial resistance is a global issue currently resulting in the deaths of hundreds of thousands of people a year worldwide. Data present in the literature illustrate the emergence of many bacterial species that display resistance to known antibiotics; Acinetobacter spp. are a good example of this. We report here that Acinetobacter radioresistens has a Baeyer-Villiger monooxygenase (Ar-BVMO) with 100% amino acid sequence identity to the ethionamide monooxygenase of multidrug-resistant (MDR) Acinetobacter baumannii. Both enzymes are only distantly phylogenetically related to other canonical bacterial BVMO proteins. Ar-BVMO not only is capable of oxidizing two anticancer drugs metabolized by human FMO3, danusertib and tozasertib, but also can oxidize other synthetic drugs, such as imipenem. The latter is a member of the carbapenems, a clinically important antibiotic family used in the treatment of MDR bacterial infections. Susceptibility tests performed by the Kirby-Bauer disk diffusion method demonstrate that imipenem-sensitive Escherichia coli BL21 cells overexpressing Ar-BVMO become resistant to this antibiotic. An agar disk diffusion assay proved that when imipenem reacts with Ar-BVMO, it loses its antibiotic property. Moreover, an NADPH consumption assay with the purified Ar-BVMO demonstrates that this antibiotic is indeed a substrate, and its product is identified by liquid chromatography-mass spectrometry to be a Baeyer-Villiger (BV) oxidation product of the carbonyl moiety of the β-lactam ring. This is the first report of an antibiotic-inactivating BVMO enzyme that, while mediating its usual BV oxidation, also operates by an unprecedented mechanism of carbapenem resistance. PMID:26459905

Escherichia coli Overexpressing a Baeyer-Villiger Monooxygenase from Acinetobacter radioresistens Becomes Resistant to Imipenem.

PubMed

Minerdi, Daniela; Zgrablic, Ivan; Castrignanò, Silvia; Catucci, Gianluca; Medana, Claudio; Terlizzi, Maria Elena; Gribaudo, Giorgio; Gilardi, Gianfranco; Sadeghi, Sheila J

2016-01-01

Antimicrobial resistance is a global issue currently resulting in the deaths of hundreds of thousands of people a year worldwide. Data present in the literature illustrate the emergence of many bacterial species that display resistance to known antibiotics; Acinetobacter spp. are a good example of this. We report here that Acinetobacter radioresistens has a Baeyer-Villiger monooxygenase (Ar-BVMO) with 100% amino acid sequence identity to the ethionamide monooxygenase of multidrug-resistant (MDR) Acinetobacter baumannii. Both enzymes are only distantly phylogenetically related to other canonical bacterial BVMO proteins. Ar-BVMO not only is capable of oxidizing two anticancer drugs metabolized by human FMO3, danusertib and tozasertib, but also can oxidize other synthetic drugs, such as imipenem. The latter is a member of the carbapenems, a clinically important antibiotic family used in the treatment of MDR bacterial infections. Susceptibility tests performed by the Kirby-Bauer disk diffusion method demonstrate that imipenem-sensitive Escherichia coli BL21 cells overexpressing Ar-BVMO become resistant to this antibiotic. An agar disk diffusion assay proved that when imipenem reacts with Ar-BVMO, it loses its antibiotic property. Moreover, an NADPH consumption assay with the purified Ar-BVMO demonstrates that this antibiotic is indeed a substrate, and its product is identified by liquid chromatography-mass spectrometry to be a Baeyer-Villiger (BV) oxidation product of the carbonyl moiety of the β-lactam ring. This is the first report of an antibiotic-inactivating BVMO enzyme that, while mediating its usual BV oxidation, also operates by an unprecedented mechanism of carbapenem resistance. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Prevalence and Antibiotic Resistance of Gram-Negative Pathogenic Bacteria Species Isolated from Periplaneta americana and Blattella germanica in Varanasi, India

PubMed Central

Wannigama, D Leshan; Dwivedi, Rishabh; Zahraei-Ramazani, Alireza

2014-01-01

Background Cockroaches are among the medically important pests found within the human habitations that cause serious public health problems. They may harbor a number of pathogenic bacteria on the external surface with antibiotic resistance. Hence, they are regarded as major microbial vectors. This study investigates the prevalence and antibiotic resistance of Gram-negative pathogenic bacteria species isolated from Periplaneta americana and Blattella germanica in Varanasi, India. Methods: Totally, 203 adult cockroaches were collected form 44 households and 52 food-handling establishments by trapping. Bacteriological examination of external surfaces of Pe. americana and Bl. germanica were carried out using standard method and antibiotics susceptibility profiles of the isolates were determined using Kirby-Bauer disc diffusion methods. Results: Among the places, we found that 54% had cockroache infestation in households and 77% in food- handling establishments. There was no significant different between the overall bacteria load of the external surface in Pe. americana (64.04%) and Bl. germanica (35.96%). However the predominant bacteria on cockroaches were Klebsiella pneumonia, Escherichia coli, Enterobacter aerogenes, and Pseudomonas aeruginosa. However, Kl. pneumoniae and Ps. aeruginosa were the most prevalent, drug-resistant strains were isolated from the cockroaches with 100% resistance to sulfamethoxazole/trimethoprim and ampicillin. For individual strains of bacteria, Escherichia coli was found to have multi-resistance to four antibiotic tested, Citrobacter freundii four, Enterobacter aerogenes and Proteus mirabilis to three. Conclusion: Cockroaches are uniformly distributed in domestic environment, which can be a possible vector for transmission of drug-resistant bacteria and food-borne diseases. PMID:25629061

The prognostic value of the QT interval and QT interval dispersion in all-cause and cardiac mortality and morbidity in a population of Danish citizens.

PubMed

Elming, H; Holm, E; Jun, L; Torp-Pedersen, C; Køber, L; Kircshoff, M; Malik, M; Camm, J

1998-09-01

To evaluate the prognostic value of the QT interval and QT interval dispersion in total and in cardiovascular mortality, as well as in cardiac morbidity, in a general population. The QT interval was measured in all leads from a standard 12-lead ECG in a random sample of 1658 women and 1797 men aged 30-60 years. QT interval dispersion was calculated from the maximal difference between QT intervals in any two leads. All cause mortality over 13 years, and cardiovascular mortality as well as cardiac morbidity over 11 years, were the main outcome parameters. Subjects with a prolonged QT interval (430 ms or more) or prolonged QT interval dispersion (80 ms or more) were at higher risk of cardiovascular death and cardiac morbidity than subjects whose QT interval was less than 360 ms, or whose QT interval dispersion was less than 30 ms. Cardiovascular death relative risk ratios, adjusted for age, gender, myocardial infarct, angina pectoris, diabetes mellitus, arterial hypertension, smoking habits, serum cholesterol level, and heart rate were 2.9 for the QT interval (95% confidence interval 1.1-7.8) and 4.4 for QT interval dispersion (95% confidence interval 1.0-19-1). Fatal and non-fatal cardiac morbidity relative risk ratios were similar, at 2.7 (95% confidence interval 1.4-5.5) for the QT interval and 2.2 (95% confidence interval 1.1-4.0) for QT interval dispersion. Prolongation of the QT interval and QT interval dispersion independently affected the prognosis of cardiovascular mortality and cardiac fatal and non-fatal morbidity in a general population over 11 years.

Orders on Intervals Over Partially Ordered Sets: Extending Allen's Algebra and Interval Graph Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zapata, Francisco; Kreinovich, Vladik; Joslyn, Cliff A.

2013-08-01

To make a decision, we need to compare the values of quantities. In many practical situations, we know the values with interval uncertainty. In such situations, we need to compare intervals. Allen’s algebra describes all possible relations between intervals on the real line, and ordering relations between such intervals are well studied. In this paper, we extend this description to intervals in an arbitrary partially ordered set (poset). In particular, we explicitly describe ordering relations between intervals that generalize relation between points. As auxiliary results, we provide a logical interpretation of the relation between intervals, and extend the results aboutmore » interval graphs to intervals over posets.« less

Fe-Distribution and Hydrogen Generation During Serpentinization

NASA Astrophysics Data System (ADS)

Klein, F.; Bach, W.; Jöns, N.; McCollom, T.; Berquó, T.; Moskowitz, B.

2009-04-01

Serpentinization of peridotite generates large amounts of dihydrogen (H2,aq), indicated by the presence of Ni-Fe alloys and low-sulfur-fugacity sulfides, e. g. awaruite and pentlandite, in serpentinites. Hydrogen is produced when ferrous iron in olivine is oxidized by water to ferric iron in secondary magnetite and serpentine. This process is strongly dependent on bulk rock composition, water-to-rock ratio and temperature. These relations were examined in thermodynamic reaction path models (using the EQ3/6 computer code) with dunitic and harzburgitic rock compositions. The model results were compared with electron microprobe analyses, bulk magnetization measurements, and Mößbauer spectroscopy of partially to fully serpentinized dunites and harzburgites from Ocean Drilling Program Leg 209, Hole 1274A, Mid-Atlantic Ridge 15 °N. These samples have mesh rims that reveal a distinct in-to-out zoning, starting with brucite (Mg# 80) at the interface with olivine, then a zone of serpentine (Mg# 95) + brucite ± magnetite, and finally serpentine + magnetite in the outermost mesh rim. The composition of co-existing serpentine and brucite in pseudomorphic mesh rims is virtually constant in most samples from 32 to 147 meters below seafloor, suggesting similar alteration conditions of olivine downhole. Bulk magnetization measurements of microdrilled mesh rims in combination with thin section petrography revealed a positive correlation of magnetite content with extent of serpentinization. Where relic olivine is present, the magnetite content is significantly lower then in fully serpentinized rocks. In these domains with sparse magnetite, Mößbauer spectra revealed Fe3+/‘ Fe values between 0.30 and 0.48 for paramagnetic minerals in the mesh rims (i. e., secondary hydrous phases). In heavily to completely serpentinized rocks with abundant magnetite, Fe3+/‘ Fe values of the paramagnetic phases are consistently higher and range from 0.53 to 0.68. In the EQ3/6 runs, a serpentine solid solution model that includes greenalite and hisingerite (Fe2Si2O5(OH)4) was used in investigating the distribution of iron between serpentine and magnetite and its oxidation state in serpentine. Our model computations predict that above 330 °C and water activities near unity, the dissolution of olivine and coeval formation of serpentine, magnetite and dihydrogen is significantly obstructed by the dearth of silica. At these temperatures, hydrogen fugacities are too low for awaruite and pentlandite to be stable. When temperatures drop below 320-330 °C, brucite becomes stable and hydrogen generation is facilitated, because the reaction of olivine to serpentine, magnetite and brucite requires no external silica. The MgO-FeO-Fe2O3-SiO2-H2O and Fe-Ni-Co-O-S phase relations observed in the mesh rims suggest that serpentine and brucite from Hole 1274A likely formed at temperatures between 150 and 250 °C and water-to-rock ratios (w/r) between 5 and 0.1. However, formation of awaruite must have taken place during main stage serpentinization at temperatures between 200-250 °C and w/r < 1, when alteration conditions were sufficiently reducing. Likewise, the model predicts the Fe3+/‘ Fe ratios of mesh-rim serpentine/brucite observed in incompletely serpentinized rocks of serpentine (0.3 to 0.5) at low w/r ratios and T < 250 °C. The calculation results furthermore indicate that elevated Fe3+/‘ Fe ratios (0.5 to 0.7) measured in fully serpentinized rocks appear to correspond to higher w/r ratios and less reducing conditions. Our study indicates that unprecedented details about the reaction sequences during serpentinization may be obtained from merging careful petrographic, magnetic, and spectroscopic analyses with comprehensive thermodynamic modeling.

Filling the blanks in temporal intervals: the type of filling influences perceived duration and discrimination performance

PubMed Central

Horr, Ninja K.; Di Luca, Massimiliano

2015-01-01

In this work we investigate how judgments of perceived duration are influenced by the properties of the signals that define the intervals. Participants compared two auditory intervals that could be any combination of the following four types: intervals filled with continuous tones (filled intervals), intervals filled with regularly-timed short tones (isochronous intervals), intervals filled with irregularly-timed short tones (anisochronous intervals), and intervals demarcated by two short tones (empty intervals). Results indicate that the type of intervals to be compared affects discrimination performance and induces distortions in perceived duration. In particular, we find that duration judgments are most precise when comparing two isochronous and two continuous intervals, while the comparison of two anisochronous intervals leads to the worst performance. Moreover, we determined that the magnitude of the distortions in perceived duration (an effect akin to the filled duration illusion) is higher for tone sequences (no matter whether isochronous or anisochronous) than for continuous tones. Further analysis of how duration distortions depend on the type of filling suggests that distortions are not only due to the perceived duration of the two individual intervals, but they may also be due to the comparison of two different filling types. PMID:25717310

Pigeons' Choices between Fixed-Interval and Random-Interval Schedules: Utility of Variability?

ERIC Educational Resources Information Center

Andrzejewski, Matthew E.; Cardinal, Claudia D.; Field, Douglas P.; Flannery, Barbara A.; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N.

2005-01-01

Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

One-way ANOVA based on interval information

NASA Astrophysics Data System (ADS)

Hesamian, Gholamreza

2016-08-01

This paper deals with extending the one-way analysis of variance (ANOVA) to the case where the observed data are represented by closed intervals rather than real numbers. In this approach, first a notion of interval random variable is introduced. Especially, a normal distribution with interval parameters is introduced to investigate hypotheses about the equality of interval means or test the homogeneity of interval variances assumption. Moreover, the least significant difference (LSD method) for investigating multiple comparison of interval means is developed when the null hypothesis about the equality of means is rejected. Then, at a given interval significance level, an index is applied to compare the interval test statistic and the related interval critical value as a criterion to accept or reject the null interval hypothesis of interest. Finally, the method of decision-making leads to some degrees to accept or reject the interval hypotheses. An applied example will be used to show the performance of this method.

System implications of the ambulance arrival-to-patient contact interval on response interval compliance.

PubMed

Campbell, J P; Gratton, M C; Salomone, J A; Lindholm, D J; Watson, W A

1994-01-01

In some emergency medical services (EMS) system designs, response time intervals are mandated with monetary penalties for noncompliance. These times are set with the goal of providing rapid, definitive patient care. The time interval of vehicle at scene-to-patient access (VSPA) has been measured, but its effect on response time interval compliance has not been determined. To determine the effect of the VSPA interval on the mandated code 1 (< 9 min) and code 2 (< 13 min) response time interval compliance in an urban, public-utility model system. A prospective, observational study used independent third-party riders to collect the VSPA interval for emergency life-threatening (code 1) and emergency nonlife-threatening (code 2) calls. The VSPA interval was added to the 9-1-1 call-to-dispatch and vehicle dispatch-to-scene intervals to determine the total time interval from call received until paramedic access to the patient (9-1-1 call-to-patient access). Compliance with the mandated response time intervals was determined using the traditional time intervals (9-1-1 call-to-scene) plus the VSPA time intervals (9-1-1 call-to-patient access). Chi-square was used to determine statistical significance. Of the 216 observed calls, 198 were matched to the traditional time intervals. Sixty-three were code 1, and 135 were code 2. Of the code 1 calls, 90.5% were compliant using 9-1-1 call-to-scene intervals dropping to 63.5% using 9-1-1 call-to-patient access intervals (p < 0.0005). Of the code 2 calls, 94.1% were compliant using 9-1-1 call-to-scene intervals. Compliance decreased to 83.7% using 9-1-1 call-to-patient access intervals (p = 0.012). The addition of the VSPA interval to the traditional time intervals impacts system response time compliance. Using 9-1-1 call-to-scene compliance as a basis for measuring system performance underestimates the time for the delivery of definitive care. This must be considered when response time interval compliances are defined.

Melodic interval perception by normal-hearing listeners and cochlear implant users

PubMed Central

Luo, Xin; Masterson, Megan E.; Wu, Ching-Chih

2014-01-01

The perception of melodic intervals (sequential pitch differences) is essential to music perception. This study tested melodic interval perception in normal-hearing (NH) listeners and cochlear implant (CI) users. Melodic interval ranking was tested using an adaptive procedure. CI users had slightly higher interval ranking thresholds than NH listeners. Both groups' interval ranking thresholds, although not affected by root note, significantly increased with standard interval size and were higher for descending intervals than for ascending intervals. The pitch direction effect may be due to a procedural artifact or a difference in central processing. In another test, familiar melodies were played with all the intervals scaled by a single factor. Subjects rated how in tune the melodies were and adjusted the scaling factor until the melodies sounded the most in tune. CI users had lower final interval ratings and less change in interval rating as a function of scaling factor than NH listeners. For CI users, the root-mean-square error of the final scaling factors and the width of the interval rating function were significantly correlated with the average ranking threshold for ascending rather than descending intervals, suggesting that CI users may have focused on ascending intervals when rating and adjusting the melodies. PMID:25324084

On Some Nonclassical Algebraic Properties of Interval-Valued Fuzzy Soft Sets

PubMed Central

2014-01-01

Interval-valued fuzzy soft sets realize a hybrid soft computing model in a general framework. Both Molodtsov's soft sets and interval-valued fuzzy sets can be seen as special cases of interval-valued fuzzy soft sets. In this study, we first compare four different types of interval-valued fuzzy soft subsets and reveal the relations among them. Then we concentrate on investigating some nonclassical algebraic properties of interval-valued fuzzy soft sets under the soft product operations. We show that some fundamental algebraic properties including the commutative and associative laws do not hold in the conventional sense, but hold in weaker forms characterized in terms of the relation =L. We obtain a number of algebraic inequalities of interval-valued fuzzy soft sets characterized by interval-valued fuzzy soft inclusions. We also establish the weak idempotent law and the weak absorptive law of interval-valued fuzzy soft sets using interval-valued fuzzy soft J-equal relations. It is revealed that the soft product operations ∧ and ∨ of interval-valued fuzzy soft sets do not always have similar algebraic properties. Moreover, we find that only distributive inequalities described by the interval-valued fuzzy soft L-inclusions hold for interval-valued fuzzy soft sets. PMID:25143964

On some nonclassical algebraic properties of interval-valued fuzzy soft sets.

PubMed

Liu, Xiaoyan; Feng, Feng; Zhang, Hui

2014-01-01

Interval-valued fuzzy soft sets realize a hybrid soft computing model in a general framework. Both Molodtsov's soft sets and interval-valued fuzzy sets can be seen as special cases of interval-valued fuzzy soft sets. In this study, we first compare four different types of interval-valued fuzzy soft subsets and reveal the relations among them. Then we concentrate on investigating some nonclassical algebraic properties of interval-valued fuzzy soft sets under the soft product operations. We show that some fundamental algebraic properties including the commutative and associative laws do not hold in the conventional sense, but hold in weaker forms characterized in terms of the relation = L . We obtain a number of algebraic inequalities of interval-valued fuzzy soft sets characterized by interval-valued fuzzy soft inclusions. We also establish the weak idempotent law and the weak absorptive law of interval-valued fuzzy soft sets using interval-valued fuzzy soft J-equal relations. It is revealed that the soft product operations ∧ and ∨ of interval-valued fuzzy soft sets do not always have similar algebraic properties. Moreover, we find that only distributive inequalities described by the interval-valued fuzzy soft L-inclusions hold for interval-valued fuzzy soft sets.

A modified Wald interval for the area under the ROC curve (AUC) in diagnostic case-control studies

PubMed Central

2014-01-01

Background The area under the receiver operating characteristic (ROC) curve, referred to as the AUC, is an appropriate measure for describing the overall accuracy of a diagnostic test or a biomarker in early phase trials without having to choose a threshold. There are many approaches for estimating the confidence interval for the AUC. However, all are relatively complicated to implement. Furthermore, many approaches perform poorly for large AUC values or small sample sizes. Methods The AUC is actually a probability. So we propose a modified Wald interval for a single proportion, which can be calculated on a pocket calculator. We performed a simulation study to compare this modified Wald interval (without and with continuity correction) with other intervals regarding coverage probability and statistical power. Results The main result is that the proposed modified Wald intervals maintain and exploit the type I error much better than the intervals of Agresti-Coull, Wilson, and Clopper-Pearson. The interval suggested by Bamber, the Mann-Whitney interval without transformation and also the interval of the binormal AUC are very liberal. For small sample sizes the Wald interval with continuity has a comparable coverage probability as the LT interval and higher power. For large sample sizes the results of the LT interval and of the Wald interval without continuity correction are comparable. Conclusions If individual patient data is not available, but only the estimated AUC and the total sample size, the modified Wald intervals can be recommended as confidence intervals for the AUC. For small sample sizes the continuity correction should be used. PMID:24552686

A modified Wald interval for the area under the ROC curve (AUC) in diagnostic case-control studies.

PubMed

Kottas, Martina; Kuss, Oliver; Zapf, Antonia

2014-02-19

The area under the receiver operating characteristic (ROC) curve, referred to as the AUC, is an appropriate measure for describing the overall accuracy of a diagnostic test or a biomarker in early phase trials without having to choose a threshold. There are many approaches for estimating the confidence interval for the AUC. However, all are relatively complicated to implement. Furthermore, many approaches perform poorly for large AUC values or small sample sizes. The AUC is actually a probability. So we propose a modified Wald interval for a single proportion, which can be calculated on a pocket calculator. We performed a simulation study to compare this modified Wald interval (without and with continuity correction) with other intervals regarding coverage probability and statistical power. The main result is that the proposed modified Wald intervals maintain and exploit the type I error much better than the intervals of Agresti-Coull, Wilson, and Clopper-Pearson. The interval suggested by Bamber, the Mann-Whitney interval without transformation and also the interval of the binormal AUC are very liberal. For small sample sizes the Wald interval with continuity has a comparable coverage probability as the LT interval and higher power. For large sample sizes the results of the LT interval and of the Wald interval without continuity correction are comparable. If individual patient data is not available, but only the estimated AUC and the total sample size, the modified Wald intervals can be recommended as confidence intervals for the AUC. For small sample sizes the continuity correction should be used.

How Different Are Our Perceptions of Equal-Tempered and Microtonal Intervals? A Behavioural and EEG Survey.

PubMed

Bailes, Freya; Dean, Roger T; Broughton, Mary C

2015-01-01

For listeners familiar with Western twelve-tone equal-tempered (12-TET) music, a novel microtonal tuning system is expected to present additional processing challenges. We aimed to determine whether this was the case, focusing on the extent to which our perceptions can be considered bottom-up (psychoacoustic and primarily perceptual) and top-down (dependent on familiarity and cognitive processing). We elicited both overt response ratings, and covert event-related potentials (ERPs), so as to compare subjective impressions of sounds with the neurophysiological processing of the acoustic signal. We hypothesised that microtonal intervals are perceived differently from 12-TET intervals, and that the responses of musicians (n = 10) and non-musicians (n = 10) are distinct. Two-note chords were presented comprising 12-TET intervals (consonant and dissonant) or microtonal (quarter tone) intervals, and ERP, subjective roughness ratings, and liking ratings were recorded successively. Musical experience mediated the perception of differences between dissonant and microtone intervals, with non-musicians giving similar ratings for each, and musicians preferring dissonant over the less commonly used microtonal intervals, rating them as less rough. ERP response amplitude was greater for consonant intervals than other intervals. Musical experience interacted with interval type, suggesting that musical expertise facilitates the sensory and perceptual discrimination of microtonal intervals from 12-TET intervals, and an increased ability to categorize such intervals. Non-musicians appear to have perceived microtonal intervals as instances of neighbouring 12-TET intervals.

Timescale- and Sensory Modality-Dependency of the Central Tendency of Time Perception.

PubMed

Murai, Yuki; Yotsumoto, Yuko

2016-01-01

When individuals are asked to reproduce intervals of stimuli that are intermixedly presented at various times, longer intervals are often underestimated and shorter intervals overestimated. This phenomenon may be attributed to the central tendency of time perception, and suggests that our brain optimally encodes a stimulus interval based on current stimulus input and prior knowledge of the distribution of stimulus intervals. Two distinct systems are thought to be recruited in the perception of sub- and supra-second intervals. Sub-second timing is subject to local sensory processing, whereas supra-second timing depends on more centralized mechanisms. To clarify the factors that influence time perception, the present study investigated how both sensory modality and timescale affect the central tendency. In Experiment 1, participants were asked to reproduce sub- or supra-second intervals, defined by visual or auditory stimuli. In the sub-second range, the magnitude of the central tendency was significantly larger for visual intervals compared to auditory intervals, while visual and auditory intervals exhibited a correlated and comparable central tendency in the supra-second range. In Experiment 2, the ability to discriminate sub-second intervals in the reproduction task was controlled across modalities by using an interval discrimination task. Even when the ability to discriminate intervals was controlled, visual intervals exhibited a larger central tendency than auditory intervals in the sub-second range. In addition, the magnitude of the central tendency for visual and auditory sub-second intervals was significantly correlated. These results suggest that a common modality-independent mechanism is responsible for the supra-second central tendency, and that both the modality-dependent and modality-independent components of the timing system contribute to the central tendency in the sub-second range.

Interval-based reconstruction for uncertainty quantification in PET

NASA Astrophysics Data System (ADS)

Kucharczak, Florentin; Loquin, Kevin; Buvat, Irène; Strauss, Olivier; Mariano-Goulart, Denis

2018-02-01

A new directed interval-based tomographic reconstruction algorithm, called non-additive interval based expectation maximization (NIBEM) is presented. It uses non-additive modeling of the forward operator that provides intervals instead of single-valued projections. The detailed approach is an extension of the maximum likelihood—expectation maximization algorithm based on intervals. The main motivation for this extension is that the resulting intervals have appealing properties for estimating the statistical uncertainty associated with the reconstructed activity values. After reviewing previously published theoretical concepts related to interval-based projectors, this paper describes the NIBEM algorithm and gives examples that highlight the properties and advantages of this interval valued reconstruction.

Neural activity related to discrimination and vocal production of consonant and dissonant musical intervals.

PubMed

González-García, Nadia; González, Martha A; Rendón, Pablo L

2016-07-15

Relationships between musical pitches are described as either consonant, when associated with a pleasant and harmonious sensation, or dissonant, when associated with an inharmonious feeling. The accurate singing of musical intervals requires communication between auditory feedback processing and vocal motor control (i.e. audio-vocal integration) to ensure that each note is produced correctly. The objective of this study is to investigate the neural mechanisms through which trained musicians produce consonant and dissonant intervals. We utilized 4 musical intervals (specifically, an octave, a major seventh, a fifth, and a tritone) as the main stimuli for auditory discrimination testing, and we used the same interval tasks to assess vocal accuracy in a group of musicians (11 subjects, all female vocal students at conservatory level). The intervals were chosen so as to test for differences in recognition and production of consonant and dissonant intervals, as well as narrow and wide intervals. The subjects were studied using fMRI during performance of the interval tasks; the control condition consisted of passive listening. Singing dissonant intervals as opposed to singing consonant intervals led to an increase in activation in several regions, most notably the primary auditory cortex, the primary somatosensory cortex, the amygdala, the left putamen, and the right insula. Singing wide intervals as opposed to singing narrow intervals resulted in the activation of the right anterior insula. Moreover, we also observed a correlation between singing in tune and brain activity in the premotor cortex, and a positive correlation between training and activation of primary somatosensory cortex, primary motor cortex, and premotor cortex during singing. When singing dissonant intervals, a higher degree of training correlated with the right thalamus and the left putamen. Our results indicate that singing dissonant intervals requires greater involvement of neural mechanisms associated with integrating external feedback from auditory and sensorimotor systems than singing consonant intervals, and it would then seem likely that dissonant intervals are intoned by adjusting the neural mechanisms used for the production of consonant intervals. Singing wide intervals requires a greater degree of control than singing narrow intervals, as it involves neural mechanisms which again involve the integration of internal and external feedback. Copyright © 2016 Elsevier B.V. All rights reserved.

Bootstrap Prediction Intervals in Non-Parametric Regression with Applications to Anomaly Detection

NASA Technical Reports Server (NTRS)

Kumar, Sricharan; Srivistava, Ashok N.

2012-01-01

Prediction intervals provide a measure of the probable interval in which the outputs of a regression model can be expected to occur. Subsequently, these prediction intervals can be used to determine if the observed output is anomalous or not, conditioned on the input. In this paper, a procedure for determining prediction intervals for outputs of nonparametric regression models using bootstrap methods is proposed. Bootstrap methods allow for a non-parametric approach to computing prediction intervals with no specific assumptions about the sampling distribution of the noise or the data. The asymptotic fidelity of the proposed prediction intervals is theoretically proved. Subsequently, the validity of the bootstrap based prediction intervals is illustrated via simulations. Finally, the bootstrap prediction intervals are applied to the problem of anomaly detection on aviation data.

Successful extension of tocilizumab infusion intervals from 4 weeks to 6 or 5 weeks in 90% of RA patients with good response to 4-week intervals.

PubMed

Saiki, Osamu; Uda, Hiroshi

2017-01-01

A period of 4 weeks (w) has been recommended as the interval between tocilizumab (TCZ) infusions for rheumatoid arthritis (RA). However, treating the patients with TCZ (8 mg/kg), we experienced that longer intervals were also effective. We conducted the study to investigate whether the intervals of TCZ infusions could extend from 4w to 5 or 6w. This was a retrospective observational study. RA patients who had shown good response to TCZ infusions at 4w intervals were enrolled, and the intervals of TCZ infusions were extended to 5w. Next, the intervals of TCZ infusion were extended to 6w for the patients who had maintained good response with 5w intervals. The patients who had maintained good response for more than two years were estimated as responders. One hundred patients were enrolled in the present study, and 62 patients maintained good response with 6w-interval infusions, and 28 patients with 5w-interval infusions, indicating that 90% of patients who had shown good response with 4w intervals could extend the intervals from 4w to 5 or 6w. The present study provides evidence that most of RA patients who showed good response to TCZ infusions at 4w could extend the intervals to 6w or 5w. This finding should be of great interest for both financial and labour reasons.

Development of antibacterial and high light transmittance bulk materials: Incorporation and sustained release of hydrophobic or hydrophilic antibiotics.

PubMed

Wang, Bailiang; Liu, Huihua; Zhang, Binjun; Han, Yuemei; Shen, Chenghui; Lin, Quankui; Chen, Hao

2016-05-01

Infection associated with medical devices is one of the most frequent complications of modern medical biomaterials. Bacteria have a strong ability to attach on solid surfaces, forming colonies and subsequently biofilms. In this work, a novel antibacterial bulk material was prepared through combining poly(dimethyl siloxane) (PDMS) with either hydrophobic or hydrophilic antibiotics (0.1-0.2 wt%). Scanning electron microscopy, water contact angle and UV-vis spectrophotometer were used to measure the changes of surface topography, wettability and optical transmission. For both gentamicin sulfate (GS) and triclosan (TCA), the optical transmission of the PDMS-GS and PDMS-TCA blend films was higher than 90%. Drug release studies showed initial rapid release and later sustained release of GS or TCA under aqueous physiological conditions. The blend films demonstrated excellent bactericidal and sufficient biofilm inhibition functions against Gram-positive bacteria (Staphylococcus aureus, S. aureus) measured by LIVE/DEAD bacterial viability kit staining method. Kirby-Bauer method showed that there was obvious zone of inhibition (7.5-12.5mm). Cytocompatibility assessment against human lens epithelial cells (HLECs) revealed that the PDMS-GS blend films had good cytocompatibility. However, the PDMS-TCA blend films showed certain cytotoxicity against HLECs. The PDMS-0.2 wt% GS blend films were compared to native PDMS in the rabbit subcutaneous S. aureus infection model. The blend films yielded a significantly lower degree of infection than native PDMS at day 7. The achievement of the PDMS-drug bulk materials with high light transmittance, excellent bactericidal function and good cytocompatibility can potentially be widely used as bio-optical materials. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Revised Ciprofloxacin Breakpoints for Salmonella: Is it Time to Write an Obituary?

PubMed

Girish, Revathy; Kumar, Anil; Khan, Sadia; Dinesh, Kavitha R; Karim, Shamsul

2013-11-01

To determine the minimum inhibitory concentration of ciprofloxacin among 50 blood stream isolates of Salmonella enterica. A total of 50 consecutive isolates of Salmonella enterica were tested for susceptibility to antimicrobials using the Kirby Bauer disk diffusion method. Minimum inhibitory concentrations were determined using Hi-Comb strips. All results were interpreted according to the CLSI guidelines. Of the 50 isolates 70%were Salmonella Typhi, 4% Salmonella paratyphi A, 2% Salmonella paratyphi B and the remaining 10% were identified only as Salmonella species. Using the CLSI 2011 breakpoints for disc diffusion, 86% (43/50) were resistant to nalidixic acid(NA), 22% (11/50) to ciprofloxacin, 12% to azithromycin, 6% to cotrimoxazole, 4% to ampicillin and 1% to chloramphenicol. The MIC50 and MIC90 of ciprofloxacin for S.Typhi were 0.181 μg/mL and 5.06 μg/mL respectively. While the same for S. paratyphi A was 0.212μg/mL and 0.228μg/mL respectively. None of the isolates were multi drug resistant and all were susceptible to ceftriaxone. Using the CLSI 2012 revised ciprofloxacin breakpoints for disc diffusion (>31mm) & MIC (<0.06 μg/mL), 90% (45/50) of these isolates were found to be resistant. MIC's of ciprofloxacin should be reported for all salmonella isolates and should be used to guide treatment. Blindly following western guidelines for a disease which is highly endemic in the subcontinent will spell the death knell of a cheap and effective drug in our armamentarium. Therefore it will be too premature to declare that "the concept of using ciprofloxacin in typhoid fever is dead!"

[Characterization of isolates of carbapenemase-producing Pseudomonas aeruginosa from seven Colombian provinces].

PubMed

Saavedra, Sandra Yamile; Duarte, Carolina; González, María Nilse; Realpe, María Elena

2014-04-01

Pseudomonas aeruginosa is an opportunistic pathogen that causes multiple infections in hospitalized patients. This microorganism has developed resistance to several antimicrobial agents, including carbapenems, which are considered to be the last therapeutic option against these infections. Carbapenem resistance of P. aeruginosa is mediated by different mechanisms: Carbapenemases class B (MBL) and A, alterations in the OprD expression and overexpression of the Mex efflux pump. To describe the presence of carbapenemases in P. aeruginosa isolates from seven Colombian provinces. A total of 57 P. aeruginosa isolates were collected between September 2012 and March 2013 from national surveillance in Colombia and were sent to the Grupo de Microbiología at the Instituto Nacional de Salud (INS) for evaluation. Iidentification and antimicrobial susceptibility were confirmed through automated method (Vitek ® 2) and disk diffusion (Kirby-Bauer) according to the Clinical and Laboratory Standards Institute, CLSI, 2013. Phenotypic and genotypic confirmation was determined using the modified Hodge test (MHT), a synergism test using imipenem, EDTA-SMA and meropenem, and conventional PCR to detect the bla KPC, bla VIM, bla IMP and bla NDM genes. Of the 57 isolates, two showed sensitivity to carbapenems. Forty-three isolates were positive for carbapenemases with a high percentage of sensitivity to colistin (76.4%, n=42). The 43 isolates producing carbapenemases showed multiple drug resistance: 72.1% were positive in the MHT and 79.1% showed MBL synergism. PCR amplification confirmed that 33 isolates were positive for bla VIM, nine were positive for bla KPC and one isolate expressed both KPC and VIM carbapenemases. No isolates showed amplified products with bla IMP and bla NDM primers. The most frequent carbapenemase was VIM, followed by KPC in an approximate ratio of 3:1.

Screening and characterization of Staphylococcus aureus from ophthalmology clinic surfaces: a proposed surveillance tool

PubMed Central

Reem, Rachel E.; Van Balen, Joany; Hoet, Armando E.; Cebulla, Colleen M.

2014-01-01

Purpose To screen environmental surfaces of an outpatient ophthalmic clinic for methicillin-susceptible and methicillin-resistant Staphylococcus aureus (MSSA and MRSA); to identify the most commonly contaminated surfaces; and to phenotype and genotype all collected isolates Design A single institution, one-year prospective environmental study Methods Commonly touched surfaces from examination rooms and common areas were targeted and sampled on a quarterly basis for one year. Samples were collected using electrostatic cloths and swabs. S. aureus was isolated using non-selective and selective media. Morphological characteristics and standard biological testing were used to confirm staphylococcal species. S. aureus isolates were phenotypically (Kirby-Bauer method) and genotypically characterized (mecA confirmation, SCCmec typing and pulsed-field gel electrophoresis). Dendrogram analysis was used to establish genetic relatedness between the isolates. Results Of 112 total samples, 27 (24%) and 5 (4%) were MSSA- and MRSA-positive, respectively. Both community-associated (SCCmec IV, USA300) and hospital-associated (SCCmec II, USA100) MRSA isolates were found. No single surface remained consistently positive with the same isolate over time and molecular analysis demonstrated high levels of diversity among isolates. Doorknobs, slit-lamp head/chinrests, and computer keyboards were frequently contaminated. Conclusions The proposed surveillance protocol successfully allowed the detection of both MSSA and MRSA contaminating important high-touch surfaces in a representative ophthalmology clinic. Frequently contaminated surfaces must be targeted for routine cleaning and disinfection as a there is a constant introduction of clones over time. Hence, other clinics may consider implementing and adapting surveillance tools, as the one here described, to help them control these important nosocomial pathogens. PMID:24412125

Assessment of landslide hazards in Kaluanui and Maakua gulches, Oahu, Hawaii, following the 9 May 1999 Sacred Falls landslide

USGS Publications Warehouse

Jibson, R.W.; Baum, R.L.

1999-01-01

One of the injured hikers later died of injuries received in the landslide. Governor Ben Cayetano of Hawaii ordered that the park be closed due to concern about continuing landslide hazard near the falls. Subsequently, Bill Meyer, District Chief for the U.S. Geological Survey (USGS) Water Resources Division in Honolulu contacted Tim Johns, Chair of the Board of Land and Natural Resources of the Hawaii Department of Land and Natural Resources (DLNR) and offered assistance in assessing slope stability in the park. Mr. Johns accepted the offer, and two landslide specialists from the USGS Geologic Hazards Team in Golden Colorado were sent to the site. On Friday, 14 May 1999, we visited the Sacred Falls landslide site with Glenn Bauer, Ed Sakoda, and Gary Moniz of DLNR. The ground investigation involved inspecting the impact area, estimating the volume of the deposit, and gathering data to help reconstruct the event. On Monday, 17 May 1999, we conducted an aerial reconnaissance of Kaluanui Gulch (Sacred Falls State Park) and Maakua Gulch in a commercial helicopter provided by DLNR. We inspected the source and path of movement of the Sacred Falls landslide of 9 May and reconnoitered the full length of both valleys to get an overview of ongoing landslide hazards there. This report gives our observations and conclusions about the Sacred Falls landslide, broadly assesses the ongoing hazard in the Kaluanui and Maakua Gulches, and suggests methods for more detailed assessment of landslide hazards here and along other trails in state parks on Oahu. Observations and conclusions in this report are based on a very brief investigation and thus are preliminary in nature.

[A rare cause of pneumonia: Shewanella putrefaciens].

PubMed

Durdu, Bülent; Durdu, Yasemin; Güleç, Nuray; Islim, Filiz; Biçer, Mualla

2012-01-01

Shewanella putrefaciens is a gram-negative, non-fermentative, oxidase positive, motile bacillus that produces hydrogen sulphide. It is found widely in the nature especially in marine environments. Although it is accepted as saprophytic, different clinical syndromes, most commonly skin or soft tissue infections, have been associated with S.putrefaciens, mainly in immunocompromised cases and patients with underlying diseases. However, pneumonia cases due to S.putrefaciens are quite limited in the literature. In this report, a case of pneumonia caused by S.putrefaciens was presented. A 43-year-old female patient was admitted to our hospital with the complaints of fever, cough, sputum and weakness. The patient has had brochiectasis since childhood and has used periodical antibiotic therapies due to pneumoniae episodes. She was diagnosed to have pneumonia based on the clinical, radiological and laboratory findings, and empirical antibiotic treatment with ciprofloxacin and ceftazidime combination was initiated. Gram-stained smear of sputum yielded abundant leucocytes and gram-negative bacteria, and the isolate grown in the sputum culture was identified as S.putrefaciens by conventional methods and API 20 NE (BioMerieux, France) system. The isolate was found susceptible to ceftriaxone, ceftazidime, cefepime, ciprofloxacin, piperacillin-tazobactam, cephoperazon-sulbactam, imipenem, amikacin, gentamicin and trimethoprime-sulphametoxazole; whereas resistant to ampicillin, amoxycillin-clavulanate, cefazolin and cefuroxime, by Kirby-Bauer disk diffusion method. According to the antibiogram results, the therapy was changed to ceftriaxone (1 x 2 g, intravenous). The patient was discharged with complete cure after 14 days of therapy. In conclusion, S.putrefaciens should be considered in patients with predisposing factors as an unusual cause of pneumonia and the characteristics such as H2S production and sensitivity to third generation cephalosporins and penicillins should be used to differentiate it from Pseudomonas aeruginosa and prevent the unnecessary use of antipseudomonal antibiotics.

Pathogen characteristics reveal novel antibacterial approaches for interstitial lung disease.

PubMed

Lu, Hai-Wen; Ji, Xiao-Bin; Liang, Shuo; Fan, Li-Chao; Bai, Jiu-Wu; Chen, Ke-Bing; Zhou, Yin; Li, Hui-Ping; Xu, Jin-Fu

2014-12-01

Interstitial lung disease (ILD) is a clinical disorder associated with changes of lung structure. Concurrent infection is a serious complication and one of the major factors that exacerbates ILD. Pathogen screening is a critical step in early diagnosis and proper treatment of ILD with secondary infection. Here we analyzed distribution and drug susceptibility of pathogens isolated from hospitalized ILD patients from January, 2007 to December, 2008 and compared them to bacterial drug resistance data in CHINET during the same period. The main specimens were from sputum culture, lavage fluid culture, lung biopsy tissue culture, and pleural effusion culture and bacterial or fungal cultures were performed on these specimens accordingly. Drug susceptibility was tested for positive bacterial cultures using disk diffusion (Kirby-Bauer method) and E Test strips in which results were determined based on the criteria of CLSI (2007). A total of 371 pathogen strains from ILD patients, including 306 bacterial strains and 65 fungal strains were isolated and cultured. Five main bacterial strains and their distribution were as follows: Klebsiella pneumoniae (31.7%), Pseudomonas aeruginosa (20.6%), Acinetobacter (12.7%), Enterobacter cloacae (8.2%), and Staphylococcus aureus (7.8%). The results showed that ILD patients who had anti-infection treatment tended to have Gram-negative bacteria, whether they acquired an infection in the hospital or elsewhere. Drug resistance screening indicated that aminoglycosides and carbapenems had lower antibiotic resistance rates. In addition, we found that the usage of immunosuppressants was associated with the increased infection rate and number of pathogens that were isolated. In conclusion, aminoglycosides and carbapenems may be selected as a priority for secondary infection to control ILD progression. Meanwhile, the use of anti-MRSA/MRCNS drugs may be considered for Staphylococcus infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Asymptomatic bacteriuria and antimicrobial susceptibility pattern of the isolates among pregnant women attending Dessie referral hospital, Northeast Ethiopia: A hospital-based cross-sectional study.

PubMed

Ali, Ismail Ebrie; Gebrecherkos, Teklay; Gizachew, Mucheye; Menberu, Martha Alemayehu

2018-05-01

The aim of the current study was to find out the prevalence of asymptomatic bacteriuria, antimicrobial susceptibility pattern of the isolates and related risk factors among pregnant women. A hospital-based cross-sectional study was carried out from February 2017 to May 2017 among asymptomatic pregnant mothers attending Dessie Referral Hospital, Northeast Ethiopia. About 10-15 mL of freshly voided midstream urine samples were collected from each study participants, and analyzed at Dessie regional research microbiology laboratory with conventional antibiotic susceptibility, and biochemical tests. Isolates were tested against commonly used antimicrobials using Kirby Bauer disc diffusion method. Data were analyzed by SPSS version 20 software and in all cases, p-values below 0.05 was considered as statistically significant. Overall, 358 pregnant women were included in the study with a mean age of 26.5±4.6 years (range, 19-43 yrs). The overall prevalence of asymptomatic bacteriuria was 56% (15.6%). Isolated microorganisms were mainly Escherichia coli and Staphylococcus aureus (for each, n=18; 31%). Escherichia coli and Staphylococcus aureus were resistant to ampicillin (66.7%), and penicillin (94.44%). The prevalence of multidrug- resistant isolates was 72.4%. History of catheterization [AOR=2.28, 95% CI=(1.03-5.06)] and anemia [AOR=4.98, 95% CI=(2.395-10.34) were statistically significant regarding the prevalence of asymptomatic bacteriuria. The overall prevalence of asymptomatic bacteriuria among pregnant women in the study area was high. The presence of asymptomatic bacteriuria and their antibiotic susceptibility test results should be taken into consideration during the management of pregnant women who are visiting antenatal care clinic.

Personalized translational epilepsy research - Novel approaches and future perspectives: Part I: Clinical and network analysis approaches.

PubMed

Rosenow, Felix; van Alphen, Natascha; Becker, Albert; Chiocchetti, Andreas; Deichmann, Ralf; Deller, Thomas; Freiman, Thomas; Freitag, Christine M; Gehrig, Johannes; Hermsen, Anke M; Jedlicka, Peter; Kell, Christian; Klein, Karl Martin; Knake, Susanne; Kullmann, Dimitri M; Liebner, Stefan; Norwood, Braxton A; Omigie, Diana; Plate, Karlheinz; Reif, Andreas; Reif, Philipp S; Reiss, Yvonne; Roeper, Jochen; Ronellenfitsch, Michael W; Schorge, Stephanie; Schratt, Gerhard; Schwarzacher, Stephan W; Steinbach, Joachim P; Strzelczyk, Adam; Triesch, Jochen; Wagner, Marlies; Walker, Matthew C; von Wegner, Frederic; Bauer, Sebastian

2017-11-01

Despite the availability of more than 15 new "antiepileptic drugs", the proportion of patients with pharmacoresistant epilepsy has remained constant at about 20-30%. Furthermore, no disease-modifying treatments shown to prevent the development of epilepsy following an initial precipitating brain injury or to reverse established epilepsy have been identified to date. This is likely in part due to the polyetiologic nature of epilepsy, which in turn requires personalized medicine approaches. Recent advances in imaging, pathology, genetics and epigenetics have led to new pathophysiological concepts and the identification of monogenic causes of epilepsy. In the context of these advances, the First International Symposium on Personalized Translational Epilepsy Research (1st ISymPTER) was held in Frankfurt on September 8, 2016, to discuss novel approaches and future perspectives for personalized translational research. These included new developments and ideas in a range of experimental and clinical areas such as deep phenotyping, quantitative brain imaging, EEG/MEG-based analysis of network dysfunction, tissue-based translational studies, innate immunity mechanisms, microRNA as treatment targets, functional characterization of genetic variants in human cell models and rodent organotypic slice cultures, personalized treatment approaches for monogenic epilepsies, blood-brain barrier dysfunction, therapeutic focal tissue modification, computational modeling for target and biomarker identification, and cost analysis in (monogenic) disease and its treatment. This report on the meeting proceedings is aimed at stimulating much needed investments of time and resources in personalized translational epilepsy research. Part I includes the clinical phenotyping and diagnostic methods, EEG network-analysis, biomarkers, and personalized treatment approaches. In Part II, experimental and translational approaches will be discussed (Bauer et al., 2017) [1]. Copyright © 2017 Elsevier Inc. All rights reserved.

The Possible Innovative Use of Bifidobacterium longum W11 in Association With Rifaximin: A New Horizon for Combined Approach?

PubMed

Graziano, Teresa; Amoruso, Angela; Nicola, Stefania; Deidda, Francesca; Allesina, Serena; Pane, Marco; Piffanelli, Pietro; Strozzi, Francesco; Mogna, Luca; Del Piano, Mario

The aim of the study was to unequivocally demonstrate the nontransmissibility of the genes mediating the resistance of the strain Bifidobacterium longum W11 (LMG P-21586) to rifaximin. Most antibiotic treatments can induce unfavorable side effects such as antibiotic-associated diarrhea, which is largely attributable to the disruption of the intestinal microbiota. The parallel intake of probiotic bacteria might reduce these events, even if with generally very poor results. In this regard, the use of antibiotic-resistant beneficial bacteria could represent a worthy strategy. Rifaximin was tested in parallel with rifampicin, rifapentine, and rifabutin, all rifamycin derivates, using 5 different concentrations. Susceptibility tests were performed by the disc diffusion method of Kirby-Bauer, and inhibition zones were measured after incubation at 37°C. B. longum BL03 was used as comparison. The B. longum W11 genome was sequenced on Illumina MiSeq with a 250 PE reads module. After mapping the reads with the reference bacterial genome, the alignment data were processed using FreeBayes software. B. longum BL03 was inhibited by all antibiotics even at the lowest concentration. In contrast, the W11 strain was inhibited by rifampicin, rifabutin, and rifaximin only at the highest concentration (512 μg/mL). The genomic analysis showed a mutation into the chromosomal DNA. No transposable elements were found, and the genetic locus was not flanked by close mobile genetic elements. B. longum W11 could be used in combined therapy with rifaximin, thus opening new focused frontiers in the probiotic era while preserving the necessary safety of use for consumers.

Role of aqueous extract of morinda citrifolia (Indian noni) ripe fruits in inhibiting dental caries-causing streptococcus mutans and streptococcus mitis.

PubMed

Kumarasamy, Barani; Manipal, Sunayana; Duraisamy, Prabu; Ahmed, Adil; Mohanaganesh, Sp; Jeevika, C

2014-11-01

Use of alternative medicine to control oral streptococci is a new topic worthy of further investigation. This study aimed to elucidate the dose-dependent anti-bacterial activity of crude aqueous extract of ripe Morinda citrifolia L. (Family: Rubiaceae) fruits against oral streptococci i.e. Streptococcus mutans and Streptococcus mitis, that cause dental caries in humans. Fresh ripe M. citrifolia fruits (750g) were ground in an electronic blender with sterile water (500ml). The crude aqueous extract was lyophilized to yield a brown colored powder. Various concentrations (1000-100μg/ ml) of the extract were tested for its antibacterial activity (Kirby and Bauer method) against whole cells of S. mutans and S. mitis. Minimum Inhibitory Concentration (MIC) was determined by micro-dilution method, using serially diluted (2 folds) fruit extract, according to the National Committee for Clinical Laboratory Standards (NCCLS). Crude aqueous extract (1000μg/ ml) of ripe M. citrifolia fruits effectively inhibited the growth of S. mutans (19±0.5 mm) and S. mitis (18.6±0.3 mm) compared to the streptomycin control (21.6±0.3 mm). The growth inhibition was clearly evident with "nil" bacteriostasis, even after 48 hours of incubation at 37°C. The MIC of the extract for S. mutans and S. mitis was 125 μg and 62.5 μg, respectively. Our results suggest that phytochemicals naturally synthesized by M. citrifolia have an inhibitory effect on oral streptococci. Furthermore, purification and molecular characterization of the "bioactive principle" would enable us to formulate a sustainable oral hygiene product.

BACTERIAL PROFILE OF NECROTIC PULPS IN CHEETAH (ACINONYX JUBATUS) CANINE TEETH.

PubMed

Almansa Ruiz, José C; Bosman, Anna-Mari; Steenkamp, Gerhard

2016-03-01

The role of microbes and their antimicrobial susceptibilities in both acute and chronic infections of the dental pulp in humans has been well studied. Presently, no data are available on endodontic pathogens in cheetahs (Acinonyx jubatus). The aim of this study was to isolate and identify the bacteria found in the canine teeth of cheetahs, where the pulp was necrotic and exposed due to a complicated crown fracture. Thirty-six microbiologic samples were taken from root canals (RCs) of the canine teeth of 19 cheetahs: one pulp sample was taken from 10 cheetahs, four samples from 2 cheetahs, two samples from 3 cheetahs, and three samples from 4 cheetahs. Exposed pulps were cultured for aerobic and anaerobic bacteria; an additional screening with a 16S rRNA-specific polymerase chain reaction (PCR) was used for the last six samples. Antimicrobial susceptibility of isolates was determined by use of the Kirby-Bauer diffusion test. In total, 59 cultivable isolates belonging to 19 microbial species and 13 genera were recovered from the 36 RCs sampled. Only two samples yielded no cultivable bacteria. Thirty-two (54.49%) of the cultivable isolates were Gram positive and 27 (45.71%) were Gram negative. The maximum number of isolates cultivated from an individual RC was six. Facultative anaerobes (62.72%) were the most common bacteria of the RCs that yielded cultivable bacteria. Of the isolates, 28.81% were aerobic and 8.47% were strict anaerobes. The antimicrobials that showed the greatest efficacy in vitro against the different bacteria isolates were amikacin and gentamicin. The more common bacterial species isolated by PCR were anaerobes (60.8%), facultative anaerobes (30.2%), and aerobes (8.6%).

High prevalence of sequence type 131 isolates producing CTX-M-15 among ESBL-producing Escherichia coli strains in north-east Iran.

PubMed

Moghanni, Marzie; Ghazvini, Kiarash; Farsiani, Hadi; Namaei, Mohammad Hasan; Derakhshan, Mohammad; Yousefi, Masoud; Maragheh, Alimohammad; Jamehdar, Saeid Amel

2018-05-25

The recent expansion of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli (E. coli) is a worldwide problem. The purpose of this study was to investigate the molecular characteristic of ESBL-producing E. coli strains in Mashhad, located in the northeast of Iran. A total of 455 clinical isolates of E. coli were collected at three hospitals in Mashhad between April and September 2015. Antibiotic susceptibility was determined with the Kirby Bauer disk diffusion test. The Combination Disc Test (CDT) was performed for the phenotypic detection of ESBLs. PCR was used for screening isolates for ESBLs typing. Phylogenetic groups and sequence type 131 were determined by multiplex-PCR. The prevalence of ESBL-producing E. coli in the collected E. coli strains was 52% (235/455). Among the 235 ESBL producer strains, 94.4% (222/235) tested positive for the CTX-M type, while 115 (48.9%), 92 (39%) and 21 (8.9%) strains were positive for TEM, OXA and SHV, respectively. Moreover, CTX-M-15 (94.1%, 209/222) was the most common ESBL-producing E. coli. Based on multiplex-PCR, the phylogenetic group B2 was the most predominant (169 isolates, 71.9%), followed by D (32, 13.6%), A (21, 8.9%), and B1 (13, 5.5%). Of the 169 groups of B2 isolates, ST131 (151, 89.3%) was the predominant clonal group. The obtained results revealed that an urgent investigation of the source and the transmission pathways of the CTX-M15-B2ST131 E. coli clone was needed to countervail this emergent public health problem. Copyright © 2018. Published by Elsevier Ltd.

Antagonistic Activity of Nocardia brasiliensis PTCC 1422 Against Isolated Enterobacteriaceae from Urinary Tract Infections.

PubMed

Jalali, Hossnieh Kafshdar; Salamatzadeh, Abdolreza; Jalali, Arezou Kafshdar; Kashani, Hamed Haddad; Asbchin, Salman Ahmadi; Issazadeh, Khosro

2016-03-01

The main drawback of current antibiotic therapies is the emergence and rapid increase in antibiotic resistance. Nocardiae are aerobic, Gram-positive, catalase-positive, non-motile actinomycetes. Nocardia brasiliensis was reported as antibiotic producer. The purpose of the study was to determine antibacterial activity of N. brasiliensis PTCC 1422 against isolated Enterobacteriaceae from urinary tract infections (UTIs). The common bacteria from UTIs were isolated from hospital samples. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to clinical and Laboratory Standards Institute guideline. Antagonistic activity of N. brasiliensis PTCC 1422 was examined with well diffusion methods. Supernatant of N. brasiliensis PTCC 1422 by submerged culture was analyzed with gas chromatography-mass spectrometry. Isolated strains included Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis. The most common pathogen isolated was E. coli (72.5%). Bacterial isolates revealed the presence of high levels of antimicrobial resistances to ceftriaxone and low levels of resistance to cephalexin. Supernatant of N. brasiliensis PTCC 1422 showed antibacterial activity against all of the isolated microorganisms in well diffusion method. The antibiotic resistance among the uropathogens is an evolving process, so a routine surveillance to monitor the etiologic agents of UTI and the resistance pattern should be carried out timely to choose the most effective empirical treatment by the physicians. Our present investigation indicates that the substances present in the N. brasiliensis PTCC 1422 could be used to inhibit the growth of human pathogen. Antibacterial resistance among bacterial uropathogen is an evolving process. Therefore, in the field on the need of re-evaluation of empirical treatment of UTIs, our present. The study has demonstrated that N. brasiliensis PTCC 1422 has a high potential for the treatment of UTIs.

Abundance and antibiotic susceptibility of Vibrio spp. isolated from microplastics

NASA Astrophysics Data System (ADS)

Laverty, A. L.; Darr, K.; Dobbs, F. C.

2016-02-01

In recent years, there has been a growing concern for `microplastics' (particles < 5 mm) in the marine environment. Since plastics degrade very slowly, they remain in the environment on much longer timescales than most natural substrates and can thus provide a novel habitat for colonization by microbial communities (Zettler et al. 2013 Environ. Sci. Technol. 47:7137). The full spectrum of relationships between microplastics and bacteria, however, is little understood. In summer 2015, we examined microplastics collected from a tributary of the lower Chesapeake Bay and determined the presence, abundance, and antibiotic-resistance profiles of Vibrio spp. found on them. We collected 22 microplastic pieces, paired seawater samples, and from them cultured 44 putative Vibrio spp. isolates, 18 of which were PCR-confirmed as V. parahaemolyticus and 3 as V. vulnificus. There were no PCR-confirmed V. cholerae isolates. We used the Kirby-Bauer disk diffusion susceptibility test to examine the isolates' response to six antibiotics: chloramphenicol (30μg), gentamicin (10μg), ampicillin (10μg), streptomycin (10μg), tetracycline (30μg), and rifampin (5μg). Vibrio isolates were susceptible to three or more of the six antibiotics tested and all were susceptible to tetracycline and chloramphenicol. There were no apparent differences between the antibiotic susceptibilities of vibrios isolated from microplastics compared to those from the water column. In every instance tested, vibrios on microplastics were enriched by at least two orders of magnitude compared to those from paired seawater samples. This study demonstrates that microplastic particles serve as a habitat for Vibrio species, in particular V. vulnificus and V. parahaemolyticus, confirming the conjecture of Zettler et al. (2013) that plastics may serve as a vector for these and other potentially pathogenic bacteria.

Floral traits influencing plant attractiveness to three bee species: Consequences for plant reproductive success.

PubMed

Bauer, Austin A; Clayton, Murray K; Brunet, Johanne

2017-05-01

The ability to attract pollinators is crucial to plants that rely on insects for pollination. We contrasted the roles of floral display size and flower color in attracting three bee species and determined the relationships between plant attractiveness (number of pollinator visits) and seed set for each bee species. We recorded pollinator visits to plants, measured plant traits, and quantified plant reproductive success. A zero-inflated Poisson regression model indicated plant traits associated with pollinator attraction. It identified traits that increased the number of bee visits and traits that increased the probability of a plant not receiving any visits. Different components of floral display size were examined and two models of flower color contrasted. Relationships between plant attractiveness and seed set were determined using regression analyses. Plants with more racemes received more bee visits from all three bee species. Plants with few racemes were more likely not to receive any bee visits. The role of flower color varied with bee species and was influenced by the choice of the flower color model. Increasing bee visits increased seed set for all three bee species, with the steepest slope for leafcutting bees, followed by bumble bees, and finally honey bees. Floral display size influenced pollinator attraction more consistently than flower color. The same plant traits affected the probability of not being visited and the number of pollinator visits received. The impact of plant attractiveness on female reproductive success varied, together with pollinator effectiveness, by pollinator species. © 2017 Bauer et al. Published by the Botanical Society of America. This work is licensed under a Creative Commons public domain license (CC0 1.0).

Assessment of physicochemical parameters and prevalence of virulent and multiple-antibiotic-resistant Escherichia coli in treated effluent of two wastewater treatment plants and receiving aquatic milieu in Durban, South Africa.

PubMed

Pillay, Leanne; Olaniran, Ademola O

2016-05-01

The poor operational status of some wastewater treatment plants often result in the discharge of inadequately treated effluent into receiving surface waters. This is of significant public health concern as there are many informal settlement dwellers (ISDs) that rely on these surface waters for their domestic use. This study investigated the treatment efficiency of two independent wastewater treatment plants (WWTPs) in Durban, South Africa and determined the impact of treated effluent discharge on the physicochemical and microbial quality of the receiving water bodies over a 6-month period. Presumptive Escherichia coli isolates were identified using biochemical tests and detection of the mdh gene via PCR. Six major virulence genes namely eae, hly, fliC, stx1, stx2, and rfbE were also detected via PCR while antibiotic resistance profiles of the isolates were determined using Kirby-Bauer disc diffusion assay. The physicochemical parameters of the wastewater samples ranged variously between 9 and 313.33 mg/L, 1.52 and 76.43 NTUs, and 6.30 and 7.87 for COD, turbidity, and pH respectively, while the E. coli counts ranged between 0 and 31.2 × 10(3) CFU/ml. Of the 200 selected E. coli isolates, the hly gene was found in 28 %, fliC in 20 %, stx2 in 17 %, eae in 14 %, with stx1 and rfbE in only 4 % of the isolates. Notable resistance was observed toward trimethoprim (97 %), tetracycline (56 %), and ampicillin (52.5 %). These results further highlight the poor operational status of these WWTPs and outline the need for improved water quality monitoring and enforcement of stringent guidelines.

Susceptibility of Malassezia pachydermatis to aminoglycosides.

PubMed

Silva, Freddy Alejandro; Conde-Felipe, Magnolia; Rosario, Inmaculada; Ferrer, Otilia; Real, Fernando; Déniz, Soraya; Acosta, Félix; Padilla, Daniel; Acosta-Hernández, Begoña

2017-12-01

Previous studies have evaluated the action of gentamicin against Malassezia pachydermatis. The aim of this study was to evaluate in vitro susceptibility of M. pachydermatis to the aminoglycosides- gentamicin, tobramycin, netilmicin and framycetin. The minimum inhibitory concentration (MIC) of gentamicin was determined following methods M27-A3 microdilution and Etest ® . The Etest ® was used to determine the minimum inhibitory concentration (MIC) of the tobramycin and netilmicin. The Kirby-Bauer test was used to determine the antibiotic susceptibility to the framycetin. The MIC50 and MIC90 were 8.12 μg/mL and 32.5 μg/mL by microdilution method for gentamicin. The MIC50, determined by the Etest ® , was 8 μg/mL for gentamicin and netilmicin and 64 μg/mL for tobramycin. The MIC90 was 16 and 32 μg/mL for gentamicin and netilmicin respectively. The MIC90 was outside of the detectable limits for tobramycin. To framycetin, 28 strains (40%) of the 70 M. pachydermatis isolates tested showed a diameter of 22 mm, 22 strains (31.42%) showed a diameter of 20 mm, 16 strains showed a diameter of ≤ 18 mm, and only 5.71% of the isolates showed a diameter of ≥ 22 mm. This study provides evidence of high in vitro activity of the aminoglycosides-gentamicin, tobramycin, netilmicin and framycetin against M. pachydermatis. For gentamicin Etest ® showed similar values of MIC50 y MIC90 that the obtained by microdilution method. We considered Etest ® method could be a good method for these calculations with aminoglycosides. © 2017 Blackwell Verlag GmbH.

Relationship between drug resistance and the clustered, regularly interspaced, short, palindromic repeat-associated protein genes cas1 and cas2 in Shigella from giant panda dung

PubMed Central

Ren, Lu; Deng, Lin-Hua; Zhang, Ri-Peng; Wang, Cheng-Dong; Li, De-Sheng; Xi, Li-Xin; Chen, Zhen-rong; Yang, Rui; Huang, Jie; Zeng, Yang-ru; Wu, Hong-Lin; Cao, San-Jie; Wu, Rui; Huang, Yong; Yan, Qi-Gui

2017-01-01

Abstract Background: To detect drug resistance in Shigella obtained from the dung of the giant panda, explore the factors leading to drug resistance in Shigella, understand the characteristics of clustered, regularly interspaced, short, palindromic repeats (CRISPR), and assess the relationship between CRISPR and drug resistance. Methods: We collected fresh feces from 27 healthy giant pandas in the Giant Panda Conservation base (Wolong, China). We identified the strains of Shigella in the samples by using nucleotide sequence analysis. Further, the Kirby-Bauer paper method was used to determine drug sensitivity of the Shigella strains. CRISPR-associated protein genes cas1 and cas2 in Shigella were detected by polymerase chain reaction (PCR), and the PCR products were sequenced and compared. Results: We isolated and identified 17 strains of Shigella from 27 samples, including 14 strains of Shigella flexneri, 2 strains of Shigella sonnei, and 1 strain of Shigella dysenteriae. Further, drug resistance to cefazolin, imipenem, and amoxicillin–clavulanic acid was identified as a serious problem, as multidrug-resistant strains were detected. Further, cas1 and cas2 showed different degrees of point mutations. Conclusion: The CRISPR system widely exists in Shigella and shares homology with that in Escherichia coli. The cas1 and cas 2 mutations contribute to the different levels of resistance. Point mutations at sites 3176455, 3176590, and 3176465 in cas1 (a); sites 3176989, 3176992, and 3176995 in cas1 (b); sites 3176156 and 3176236 in cas2 may affect the resistance of bacteria, cause emergence of multidrug resistance, and increase the types of drug resistance. PMID:28207509

High prevalence of multidrug-resistant Escherichia coli isolates from children with and without diarrhoea and their susceptibility to the antibacterial activity of extracts/fractions of fruits native to Mexico.

PubMed

Uribe-Beltrán, Magdalena de Jesús; Ahumada-Santos, Yesmi Patricia; Díaz-Camacho, Sylvia Páz; Eslava-Campos, Carlos Alberto; Reyes-Valenzuela, Jesús Ernesto; Báez-Flores, María Elena; Osuna-Ramírez, Ignacio; Delgado-Vargas, Francisco

2017-07-01

This paper aims to evaluate the antimicrobial resistance of Esherichia coli isolates from children under 5 years old, with and without diarrhoea, who were hospital outpatients in Culiacan, Sinaloa, Mexico. It also looks at the antimicrobial activity of fruit extracts against selected multidrug-resistant (MDR) E. coli strains. A total of 205 E. coli isolates from stool samples were collected from 94 children under 5 years old who were outpatients from two hospitals in the city of Culiacan, Sinaloa, Mexico, during the autumn/winter of 2003/04; their resistance profiles to 19 commercial antimicrobials were investigated using the Kirby-Bauer method. The antibacterial activities of extracts/fractions of fruits (i.e. uvalama, Vitex mollis; ayale, Crescentia alata; and arrayan, Psidium sartorianum) were evaluated using the broth microdilution method. All E. coli isolates were susceptible to amikacin, nitrofurantoin and meropenem, and approximately 96 % were resistant to at least one antimicrobial, especially carbenicillin (93.2 %), cefuroxime sodium (53.7 %), ampicillin (40 %) and trimethoprim/sulfamethoxazole (35.1 %). Likewise, the frequency of MDR strains (44.9 %) was high, and no significant association with diarrhoea symptoms was found. Remarkably, all fruit extracts/fractions showed antibacterial activity against some, but not all, MDR isolates. The lowest minimal inhibitory concentration values were for the hexane fraction of arrayan (0.25 mg ml-1). A high number of antimicrobial-resistant E. coli (especially to β-lactams and sulfonamides) and MDR isolates were detected in children under 5 years old, irrespective of diarrhoea symptoms; this is novel information for Culiacan, Sinaloa, Mexico. Moreover, our results showed that the studied fruit extracts/fractions are potential alternative or complementary treatments for MDR E. coli strains.

Search for and limits on plume activity on Mimas, Tethys, and Dione with the Cassini Visual Infrared Mapping Spectrometer (VIMS)

USGS Publications Warehouse

Buratti, B.J.; Faulk, S.P.; Mosher, J.; Baines, K.H.; Brown, R.H.; Clark, R.N.; Nicholson, P.D.

2011-01-01

Cassini Visual Infrared Mapping Spectrometer (VIMS) observations of Mimas, Tethys, and Dione obtained during the nominal and extended missions at large solar phase angles were analyzed to search for plume activity. No forward scattered peaks in the solar phase curves of these satellites were detected. The upper limit on water vapor production for Mimas and Tethys is one order of magnitude less than the production for Enceladus. For Dione, the upper limit is two orders of magnitude less, suggesting this world is as inert as Rhea (Pitman, K.M., Buratti, B.J., Mosher, J.A., Bauer, J.M., Momary, T., Brown, R.H., Nicholson, P.D., Hedman, M.M. [2008]. Astrophys. J. Lett. 680, L65-L68). Although the plumes are best seen at ???2.0. ??m, Imaging Science Subsystem (ISS) Narrow Angle Camera images obtained at the same time as the VIMS data were also inspected for these features. None of the Cassini ISS images shows evidence for plumes. The absence of evidence for any Enceladus-like plumes on the medium-sized saturnian satellites cannot absolutely rule out current geologic activity. The activity may below our threshold of detection, or it may be occurring but not captured on the handful of observations at large solar phase angles obtained for each moon. Many VIMS and ISS images of Enceladus at large solar phase angles, for example, do not contain plumes, as the active "tiger stripes" in the south pole region are pointed away from the spacecraft at these times. The 7-year Cassini Solstice Mission is scheduled to gather additional measurements at large solar phase angles that are capable of revealing activity on the saturnian moons. ?? 2011 Elsevier Inc.

Role of Aqueous Extract of Morinda Citrifolia (Indian Noni) Ripe Fruits in Inhibiting Dental Caries-Causing Streptococcus Mutans and Streptococcus Mitis

PubMed Central

Kumarasamy, Barani; Manipal, Sunayana; Duraisamy, Prabu; Ahmed, Adil; Mohanaganesh, SP; Jeevika, C

2014-01-01

Objectives: Use of alternative medicine to control oral streptococci is a new topic worthy of further investigation. This study aimed to elucidate the dose-dependent anti-bacterial activity of crude aqueous extract of ripe Morinda citrifolia L. (Family: Rubiaceae) fruits against oral streptococci i.e. Streptococcus mutans and Streptococcus mitis, that cause dental caries in humans. Methods: Fresh ripe M. citrifolia fruits (750g) were ground in an electronic blender with sterile water (500ml). The crude aqueous extract was lyophilized to yield a brown colored powder. Various concentrations (1000-100μg/ ml) of the extract were tested for its antibacterial activity (Kirby and Bauer method) against whole cells of S. mutans and S. mitis. Minimum Inhibitory Concentration (MIC) was determined by micro-dilution method, using serially diluted (2 folds) fruit extract, according to the National Committee for Clinical Laboratory Standards (NCCLS). Results: Crude aqueous extract (1000μg/ ml) of ripe M. citrifolia fruits effectively inhibited the growth of S. mutans (19±0.5 mm) and S. mitis (18.6±0.3 mm) compared to the streptomycin control (21.6±0.3 mm). The growth inhibition was clearly evident with “nil” bacteriostasis, even after 48 hours of incubation at 37°C. The MIC of the extract for S. mutans and S. mitis was 125 μg and 62.5 μg, respectively. Conclusion: Our results suggest that phytochemicals naturally synthesized by M. citrifolia have an inhibitory effect on oral streptococci. Furthermore, purification and molecular characterization of the “bioactive principle” would enable us to formulate a sustainable oral hygiene product. PMID:25628701

Low level arsenic promotes progressive inflammatory angiogenesis and liver blood vessel remodeling in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Straub, Adam C.; Stolz, Donna B.; Vin, Harina

2007-08-01

The vascular effects of arsenic in drinking water are global health concerns contributing to human disease worldwide. Arsenic targets the endothelial cells lining blood vessels, and endothelial cell activation or dysfunction may underlie the pathogenesis of both arsenic-induced vascular diseases and arsenic-enhanced tumorigenesis. The purpose of the current studies was to demonstrate that exposing mice to drinking water containing environmentally relevant levels of arsenic promoted endothelial cell dysfunction and pathologic vascular remodeling. Increased angiogenesis, neovascularization, and inflammatory cell infiltration were observed in Matrigel plugs implanted in C57BL/6 mice following 5-week exposures to 5-500 ppb arsenic [Soucy, N.V., Mayka, D., Klei,more » L.R., Nemec, A.A., Bauer, J.A., Barchowsky, A., 2005. Neovascularization and angiogenic gene expression following chronic arsenic exposure in mice. Cardiovasc.Toxicol 5, 29-42]. Therefore, functional in vivo effects of arsenic on endothelial cell function and vessel remodeling in an endogenous vascular bed were investigated in the liver. Liver sinusoidal endothelial cells (LSEC) became progressively defenestrated and underwent capillarization to decrease vessel porosity following exposure to 250 ppb arsenic for 2 weeks. Sinusoidal expression of PECAM-1 and laminin-1 proteins, a hallmark of capillarization, was also increased by 2 weeks of exposure. LSEC caveolin-1 protein and caveolae expression were induced after 2 weeks of exposure indicating a compensatory change. Likewise, CD45/CD68-positive inflammatory cells did not accumulate in the livers until after LSEC porosity was decreased, indicating that inflammation is a consequence and not a cause of the arsenic-induced LSEC phenotype. The data demonstrate that the liver vasculature is an early target of pathogenic arsenic effects and that the mouse liver vasculature is a sensitive model for investigating vascular health effects of arsenic.« less

Comparative phenotypic and genotypic analyses of Salmonella Rissen that originated from food animals in Thailand and United States.

PubMed

Pornsukarom, S; Patchanee, P; Erdman, M; Cray, P F; Wittum, T; Lee, J; Gebreyes, W A

2015-03-01

Salmonella enterica serovar Rissen has been recognized as one of the most common serovar among humans and pork production systems in different parts of the world, especially Asia. In the United States, this serovar caused outbreaks but its epidemiologic significance remains unknown. The objectives of this study were to compare the phenotypic (antimicrobial susceptibility) and genotypic attributes of Salmonella Rissen isolated in Thailand (Thai) and the United States (US). All the Thai isolates (n = 30) were recovered from swine faecal samples. The US isolates (n = 35) were recovered from swine faecal samples (n = 29), cattle (n = 2), chicken (n = 2), dog (n = 1) and a ready-to-eat product (n = 1). The antimicrobial susceptibility of isolates was determined using the Kirby-Bauer disk diffusion method with a panel of 12 antimicrobials. Pulse-field gel electrophoresis (PFGE) was used to determine the genotypic diversity of isolates. All Thai isolates showed multidrug resistance (MDR) with the most frequent antibiotic resistance shown against ampicillin (100%), sulfisoxazole (96.7%), tetracycline (93.3%), streptomycin (90%) and chloramphenicol (30%). About half of the isolates of USA origin were pan-susceptible and roughly 30% were resistant to only tetracycline (R-type: Te). Salmonella Rissen isolated from Thailand and the USA in this study were found to be clonally unrelated. Genotypic analyses indicated that isolates were clustered primarily based on the geographic origin implying the limited clonality among the strains. Clonal relatedness among different host species within the same geography (USA) was found. We found genotypic similarity in Thai and US isolates in few instances but with no epidemiological link. Further studies to assess propensity for increased inter-regional transmission and dissemination is warranted. © 2014 Blackwell Verlag GmbH.

An Inexpensive Bismuth-Petrolatum Dressing for Treatment of Burns

PubMed Central

Chattopadhyay, Arhana; Chang, Kathleen; Nguyen, Khoa; Galvez, Michael G.; Legrand, Anais; Davis, Christopher; McGoldrick, Rory; Long, Chao; Pham, Hung

2016-01-01

Background: Xeroform remains the current standard for treating superficial partial-thickness burns but can be prohibitively expensive in developing countries with prevalent burn injuries. This study (1) describes the production of an alternative low-cost dressing and (2) compares the alternative dressing and Xeroform using the metrics of cost-effectiveness, antimicrobial activity, and biocompatibility in vitro, and wound healing in vivo. Methods: To produce the alternative dressing, 3% bismuth tribromophenate powder was combined with petroleum jelly by hand and applied to Kerlix gauze. To assess cost-effectiveness, the unit costs of Xeroform and components of the alternative dressing were compared. To assess antimicrobial properties, the dressings were placed on agar plated with Escherichia coli and the Kirby-Bauer assay performed. To assess biocompatibility, the dressings were incubated with human dermal fibroblasts and cells stained with methylene blue. To assess in vivo wound healing, dressings were applied to excisional wounds on rats and the rate of re-epithelialization calculated. Results: The alternative dressing costs 34% of the least expensive brand of Xeroform. Antimicrobial assays showed that both dressings had similar bacteriostatic effects. Biocompatibility assays showed that there was no statistical difference (P < 0.05) in the cytotoxicity of Xeroform, alternative dressing, and Kerlix gauze. Finally, the in vivo healing model showed no statistical difference (P < 0.05) in mean re-epithelialization time between Xeroform (13.0 ± 1.6 days) and alternative dressing (13.5 ± 1.0 days). Conclusions: Xeroform is biocompatible, reduces infection, and enhances healing of burn wounds by preventing desiccation and mechanical trauma. Handmade petrolatum gauze may be a low-cost replacement for Xeroform. Future studies will focus on clinical trials in burn units. PMID:27482485

Molecular detection of metallo-β-lactamase gene blaVIM-1 in imipenem-resistant Pseudomonas aeruginosa strains isolated from hospitalized patients in the hospitals of Isfahan.

PubMed

Sedighi, Mansour; Vaez, Hamid; Moghoofeie, Mohsen; Hadifar, Shima; Oryan, Golfam; Faghri, Jamshid

2015-01-01

Pseudomonas aeruginosa is an opportunistic human pathogen that causes serious problems, especially in people, who have immunodeficiency. In recent times, metallo-β-lactamase (MBLs) resistance in this bacterium has led to some difficulties in treating bacterial infections. The metallo-beta-lactamase family of genes, including blaVIM-1, is being reported with increasing frequency worldwide. The aim of this study is the detection of the metallo-β-lactamase gene blaVIM-1 in imipenem-resistant P. aeruginosa (IRPA) strains isolated from hospitalized patients. In this study, 106 P. aeruginosa samples were isolated from various nosocomial infections. The isolates were identified, tested for susceptibility to various antimicrobial agents by the Kirby-Bauer disk diffusion method, and all the imipenem-resistant isolates were screened for the presence of MBLs by using the combined disk (IMP-EDTA). The minimal inhibitory concentration (MIC) of imipenem was determined by E-test on the Mueller-Hinton agar. To detect the blaVIM-1 gene, the isolates were subjected to a polymerase chain reaction (PCR). Of all the P. aeruginosa isolates, 62 (58.5%) were found to be imipenem-resistant P. aeruginosa (MIC ≥32 μg/ml). Twenty-six (42%) of the imipenem-resistant isolates were MBL positive. None of these isolates carried the blaVIM-1 gene using the PCR assay. The results demonstrated the serious therapeutic threat of the MBL-producing P. aeruginosa populations. The rate of imipenem resistance due to MBL was increased dramatically. Early detection and infection-control practices are the best antimicrobial strategies for this organism. None of MBL-producing isolates in this study carry the blaVIM-1 gene; therefore, another gene in the MBL family should be investigated.

Biofilm and metallo beta-lactamase production among the strains of Pseudomonas aeruginosa and Acinetobacter spp. at a Tertiary Care Hospital in Kathmandu, Nepal.

PubMed

Baniya, Bandana; Pant, Narayan Dutt; Neupane, Sanjeev; Khatiwada, Saroj; Yadav, Uday Narayan; Bhandari, Nisha; Khadka, Rama; Bhatta, Sabita; Chaudhary, Raina

2017-11-02

Pseudomonas aeruginosa and Acinetobacter spp. are found to be associated with biofilm and metallo-β-lactamase production and are the common causes of serious infections mainly in hospitalized patients. So, the main aims of this study were to determine the rates of biofilm production and metallo beta-lactamase production (MBL) among the strains of Pseudomonas aeruginosa and Acinetobacter spp. isolated from hospitalized patients. A total of 85 P. aeruginosa isolates and 50 Acinetobacter spp. isolates isolated from different clinical specimens from patients admitted to Shree Birendra Hospital, Kathmandu, Nepal from July 2013 to May 2014 were included in this study. The bacterial isolates were identified with the help of biochemical tests. Modified Kirby-Bauer disc diffusion technique was used for antimicrobial susceptibility testing. Combined disc diffusion technique was used for the detection of MBL production, while Congo red agar method and tube adherence method were used for detection of biofilm production. Around 16.4% of P. aeruginosa isolates and 22% of the strains of Acinetobacter spp. were metallo β-lactamase producers. Out of 85 P. aeruginosa isolates, 23 (27.05%) were biofilm producers according to tube adherence test while, only 13 (15.29%) were biofilm producers as per Congo red agar method. Similarly, out of 50 Acinetobacter spp. 7 (14%) isolates were biofilm producers on the basis of tube adherence test, while only 5 (10%) were positive for biofilm production by Congo red agar method. Highest rates of susceptibility of P. aeruginosa as well as Acinetobacter spp. were seen toward colistin. In our study, biofilm production and metallo beta-lactamase production were observed among Pseudomonas aeruginosa and Acinetobacter spp. However, no statistically significant association could be established between biofilm production and metallo beta-lactamase production.

Isolation of Streptococcus pyogenes from children with pharyngitis and emm type analysis.

PubMed

Khosravi, Azar D; Ebrahimifard, Nasim; Shamsizadeh, Ahmad; Shoja, Saeed

2016-05-01

The group A streptococcus (GAS) M protein, encoded by the emm gene, acts as a major virulence factor. Emm-typing is the GAS gold standard molecular typing and is based on the DNA sequence of the nucleotides of the emm gene. The aim of the present study was to isolate GAS from patients and to detect the emm types of the isolates using emm typing. A total of 1000 throat samples were collected from patients with pharyngitis referred to Aboozar Children's Hospital in Ahvaz, Iran. We performed antimicrobial susceptibility testing on all isolates using the Kirby-Bauer disk diffusion method. Additionally, amplification of the emm gene was performed using polymerase chain reaction using the standard primers and described protocol. From all throat samples screened, 25 isolates (2.5%) were identified as GAS. Antibiotic susceptibility testing revealed that all the GAS isolates were susceptible to penicillin and erythromycin, but 44% showed resistance to vancomycin. Based on polymerase chain reaction for the emm gene, the obtained emm types were: emm-3, observed in 20 isolates (80%); emm-1 observed in four isolates (16%); and emm-75 observed in one isolate (4%). The result of the present study showed that penicillin and erythromycin are still the most effective antibiotics against the organism. The emm typing revealed that emm type-3 was detected in most of the isolates from patients with purulent pharyngitis. On the basis of the findings of this study, we may conclude that emm typing provides new insights on the genetic diversity of the M proteins, and is of demonstrable value for molecular studies of GAS. Copyright © 2016. Published by Elsevier Taiwan LLC.

Electrospun matrices for localised controlled drug delivery: release of tetracycline hydrochloride from layers of polycaprolactone and poly(ethylene-co-vinyl acetate).

PubMed

Alhusein, Nour; Blagbrough, Ian S; De Bank, Paul A

2012-12-01

We report the controlled release of tetracycline (Tet) HCl from a three-layered electrospun matrix for the first time. Five formulations of electrospun poly-ε-caprolactone (PCL) and poly(ethylene-co-vinyl acetate) (PEVA) have been designed, prepared as micro/nanofibre layers, and assayed for the controlled release of the clinically useful antibiotic Tet HCl with potential applications in wound healing and especially in complicated skin and skin-structure infections. Tet HCl was also chosen as a model drug possessing a good ultraviolet (UV) chromophore and capable of fluorescence together with limited stability. Tet HCl was successfully incorporated (essentially quantitatively at 3 %, w/w) and provided controlled release from multilayered electrospun matrices. The Tet HCl release test was carried out by a total immersion method on 2 × 2 cm(2) electrospun fibrous mats in Tris or phosphate-buffered saline heated to 37 °C. The formulation PCL/PEVA/PCL with Tet HCl in each layer gave a large initial (burst) release followed by a sustained release. Adding a third layer to the two-layered formulations led to release being sustained from 6 days to more than 15 days. There was no detectable loss of Tet chemical stability (as shown by UV and NMR) or bioactivity (as shown by a modified Kirby-Bauer disc assay). Using Tet HCl-sensitive bacteria, Staphylococcus aureus (ATCC 25923), the Tet HCl-loaded three-layered matrix formulations were still showing significantly higher antibacterial effects on days 4 and 5 than commercially available Antimicrobial Susceptibility Test Discs of Tet HCl. Electrospinning provides good encapsulation efficiency of Tet HCl within PCL/PEVA/PCL polymers in micro/nanofibre layers which display sustained antibiotic release.

A one-year prospective study on the antibiotic resistance of E. coli strains isolated in urinary specimens of children hospitalized at the University Pediatric Medical Center in Novi Sad, Serbia.

PubMed

Jakovljević, E; Ilić, K; Jelesić, Z; Konstantinidis, G

2013-12-01

Urinary tract infections (UTIs), the most common serious bacterial infections in children, are frequently caused by Escherichia coli. The purpose of this study was to investigate E. coli resistance/multidrug resistance to antibiotics most frequently used for UTIs. Children 0-18 years of age, hospitalized at the University Pediatric Hospital in Novi Sad, Serbia, were included in a 1-year observational prospective study. The microbiological analysis was performed using the standard Kirby-Bauer disk diffusion method. The results were analyzed using WHONET 5.4 software. E. coli was isolated from 61.7 % of positive urine specimens. In general, higher average E. coli antibiotic resistance was found in infants and toddlers compared to children and adolescents (33.4 vs. 25.0 %) (p < 0.0001). Furthermore, it was observed that the average resistance to all the tested antibiotics was higher in boys than in girls (37.0 vs. 25.1 %) (p < 0.0001). E. coli was highly susceptible to piperacillin/tazobactam (>93.1 %), amikacin (86.3 %), quinolones (>75.0 %), and penems (>96.6 %). The prevalence of multiresistant E. coli strains was significantly higher in infants and toddlers (72.3 vs. 36.8 %) (p < 0.0001). E. coli, a common cause of UTIs in children admitted to pediatric hospitals, is highly resistant/multidrug-resistant to commonly used antibiotics. Higher average resistance is found in infants and toddlers than in children and adolescents, as well as in boys compared to girls. These findings are important for the regional empiric therapy of UTIs and call for actions to decrease E. coli antibiotic resistance.

PubMed Central

NASROLAHEI, M.; VAHEDI, M.; MALEKI, I.

2013-01-01

Summary Objective. Urinary tract infections (UTIs) are amongst the most common infections and account for large proportion of antibacterial drug consumption. The aim of this study was to determine the rate and the etiologic agents of UTIs in inhabitants of rehabilitation centers of Mazandaran province in northern Iran and to evaluate the antimicrobial susceptibility patterns of the uropathogens isolated. Methods. Clean catch midstream urine sample was collected from each of 314 participants (163 males, 151 females) residing in 12 rehabilitation centers of Ramsar, Nowshahr, Chalous, Amol, Sari and Behshahr. Urine specimens were cultured and bacterial isolates were identified by conventional methods. All urines fulfilling the criteria for the presence of significant bacteriuria (≥104 cfu / ml urine) were defined as positive. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method. Results. The rate of urinary tract infection was 30.9% with the highest rate in pediatrics (p < 0.0001).The prevalence of UTIs were shown to be higher in females than in males with the rate of 46.3% in young aged females (20-29 years), 60% in middle aged group (40-49 years) and 50% in elderly (> 50 years). Bacteria most frequently isolated from urine specimens was Escherichia coli (39.2%) with the highest rate of infection in females age group < 10 years (p < 0.001). Among the antibiotics tested against the isolated organisms for susceptibility test, ceftriaxone and gentamicin maintain good activity against the majority of gram negative bacteria that cause UTIs recovered from individuals with intellectual disability. Vancomycin was effective against Staphylococcus aureus. Conclusions. This survey shows that the prevalence of UTIs among inhabitants of institutions for mentally retarded persons in Mazandaran province of Iran is much higher than normal population. PMID:24783897

Urinary tract infection among intellectual disability individuals "etiology and antibiotic resistance patterns" in rehabilitation centers of Mazandaran province, Northern Iran.

PubMed

Nasrolahei, M; Poorhagibagher, M; Vahedi, M; Maleki, I

2013-09-01

OBJECTIVE. Urinary tract infections (UTIs) are amongst the most common infections and account for large proportion of antibacterial drug consumption. The aim of this study was to determine the rate and the etiologic agents of UTIs in inhabitants of rehabilitation centers of Mazandaran province in northern Iran and to evaluate the antimicrobial susceptibility patterns of the uropathogens isolated. Clean catch midstream urine sample was collected from each of 314 participants (163 males, 151 females) residing in 12 rehabilitation centers of Ramsar, Nowshahr, Chalous, Amol, Sari and Behshahr. Urine specimens were cultured and bacterial isolates were identified by conventional methods. All urines fulfilling the criteria for the presence of significant bacteriuria (> or = 10(4) cfu/ml urine) were defined as positive. Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method. The rate of urinary tract infection was 30.9% with the highest rate in pediatrics (p < 0.0001).The prevalence of UTIs were shown to be higher in females than in males with the rate of 46.3% in young aged females (20-29 years), 60% in middle aged group (40-49 years) and 50% in elderly (> 50 years). Bacteria most frequently isolated from urine specimens was Escherichia coli (39.2%) with the highest rate of infection in females age group < 10 years (p < 0.001). Among the antibiotics tested against the isolated organisms for susceptibility test, ceftriaxone and gentamicin maintain good activity against the majority of gram negative bacteria that cause UTIs recovered from individuals with intellectual disability. Vancomycin was effective against Staphylococcus aureus. This survey shows that the prevalence of UTIs among inhabitants of institutions for mentally retarded persons in Mazandaran province of Iran is much higher than normal population.

Changing prevalence and antibiotic drug resistance pattern of pathogens seen in community-acquired pediatric urinary tract infections at a tertiary care hospital of North India.

PubMed

Patwardhan, Vrushali; Kumar, Dinesh; Goel, Varun; Singh, Sarman

2017-01-01

The aim and objective of this study was to assess the temporal changes in the microbiological profiles and antimicrobial resistance patterns of uropathogens in pediatric community-acquired UTI. This is a retrospective analysis of data collected over a Scattered period of 5 years. The baseline data collected were from January to December 2009, and the second period considered for comparison was from January to December 2014. Urine specimens from children (<17 years) suspected of UTI were cultured by a semi-quantitative method on cysteine lactose electrolyte-deficient medium. Antibiotic sensitivity was put up by Kirby-Bauer disc diffusion method as per the Clinical and Laboratory Standard Institute guidelines. In the year 2009, 340 of 2104 (16.15%) urine specimens yielded significant colony count, whereas in 2014, it was 407 of 2212 (18.39%) ( P = 0.051). Escherichia coli was the predominant pathogen and was significantly more prevalent in girls than in boys ( P < 0.0001) during both periods. There was a significant overall increase in resistance to ampicillin (from 40.29% to 58.72%), amoxyclav (from 26.17% to 40.54%), nitrofurantoin (from 28.82% to 39.06%), and norfloxacin (from 30% to 41.42%). However, the maximum increase in the resistance was noted for co-trimoxazole from 35.58% in 2009 to 63.39% in 2014 ( P = 0.0000058). The prevalence of extended-spectrum beta-lactamases (ESBLs) has also significantly increased from 21.7% to 33.16% ( P = 0.0045). Although E. coli remains the prime pathogen in pediatric UTI, the prevalence of resistance has dramatically increased over the 5-year study period. Our study highlights the emergence of community-acquired ESBL-producing uropathogens in children proclaiming treatment challenges.

Asymptomatic bacteriuria and antimicrobial susceptibility pattern of the isolates among pregnant women attending Dessie referral hospital, Northeast Ethiopia: A hospital-based cross-sectional study

PubMed Central

Ali, Ismail Ebrie; Gebrecherkos, Teklay; Gizachew, Mucheye

2018-01-01

Objective The aim of the current study was to find out the prevalence of asymptomatic bacteriuria, antimicrobial susceptibility pattern of the isolates and related risk factors among pregnant women. Material and methods A hospital-based cross-sectional study was carried out from February 2017 to May 2017 among asymptomatic pregnant mothers attending Dessie Referral Hospital, Northeast Ethiopia. About 10–15 mL of freshly voided midstream urine samples were collected from each study participants, and analyzed at Dessie regional research microbiology laboratory with conventional antibiotic susceptibility, and biochemical tests. Isolates were tested against commonly used antimicrobials using Kirby Bauer disc diffusion method. Data were analyzed by SPSS version 20 software and in all cases, p-values below 0.05 was considered as statistically significant. Results Overall, 358 pregnant women were included in the study with a mean age of 26.5±4.6 years (range, 19–43 yrs). The overall prevalence of asymptomatic bacteriuria was 56% (15.6%). Isolated microorganisms were mainly Escherichia coli and Staphylococcus aureus (for each, n=18; 31%). Escherichia coli and Staphylococcus aureus were resistant to ampicillin (66.7%), and penicillin (94.44%). The prevalence of multidrug- resistant isolates was 72.4%. History of catheterization [AOR=2.28, 95% CI=(1.03–5.06)] and anemia [AOR=4.98, 95% CI=(2.395–10.34) were statistically significant regarding the prevalence of asymptomatic bacteriuria. Conclusion The overall prevalence of asymptomatic bacteriuria among pregnant women in the study area was high. The presence of asymptomatic bacteriuria and their antibiotic susceptibility test results should be taken into consideration during the management of pregnant women who are visiting antenatal care clinic. PMID:29733799

Evaluation of synergistic antimicrobial effect of vitamins (A, B1, B2, B6, B12, C, D, E and K) with antibiotics against resistant bacterial strains.

PubMed

Shahzad, Shakeel; Ashraf, M Adnan; Sajid, M; Shahzad, Aqeel; Rafique, Azhar; Mahmood, M Shahid

2018-02-02

Multiple drug resistant super bugs of Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus (MRSA) are becoming challenge for healthcare professionals. In this study, vitamins were evaluated for synergistic activity with the antibiotics. Synergistic effect between antibiotic and stock solutions of vitamins is evaluated by using Kirby-Bauer disc diffusion assay. Distilled water and propylene glycol were used as solvent for water soluble vitamins and fat-soluble vitamins respectively. The final concentration of 10mg/ml of each water-soluble vitamin B1 (Thiamine), B2 (Riboflavin), B6 (Pyridoxine) B12 (Methylcobalamin), C (Ascorbic acid) and 0.1mg/ml of each fat soluble vitamin A (retinol), D (cholecalciferol) E (αTocopherol) K (Menadione) were used with the antibiotics. The results depicted that vitamin K and E have better synergistic activity with piperacillin-tazobactam, imipenem and doripenem antibiotics against A. baumannii. While vitamin B1, B2 and B12 showed remarkable synergistic activity with linezolid against MRSA. Vitamin B1 was further tested to have better synergism with antibiotics oxacillin, tetracycline, rifampicin and linezolid against MRSA. The fat-soluble vitamins E and K were good in synergism against Gram negative A. baumannii while water soluble vitamins as B1, B2 and B12 were effective against MRSA but not against A. baumannii. This synergistic action of vitamins with the antibiotics can be used as a tool to treat multiple drug resistant super bugs with further evaluation at molecular level. Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Proposal of a Classification System for the Assessment and Treatment of Prominent Ear Deformity.

PubMed

Lee, Youngdae; Kim, Young Seok; Lee, Won Jai; Rha, Dong Kyun; Kim, Jiye

2018-06-01

Prominent ear is the most common external ear deformity. To comprehensively treat prominent ear deformity, adequate comprehension of its pathophysiology is crucial. In this article, we analyze cases of prominent ear and suggest a simple classification system and treatment algorithm according to pathophysiology. We retrospectively reviewed a total of 205 Northeast Asian patients' clinical data who underwent an operation for prominent ear deformity. Follow-up assessments were conducted 3, 6, and 12 months after surgery. Prominent ear deformities were classified by diagnostic checkpoints. Class I (simple prominent ear) includes prominent ear that developed with the absence of the antihelix without conchal hypertrophy. Class II (mixed-type prominent ear) is defined as having not only a flat antihelix, but also conchal excess. Class III (conchal-type prominent ear) has an enlarged conchal bowl with a well-developed antihelix. Among the three types of prominent ear, class I was most frequent (162 patients, 81.6%). Class II was observed in 28 patients (13.6%) and class III in 10 patients (4.8%). We used the scaphomastoid suture method for correction of antihelical effacement, the anterior approach conchal resection for correction of conchal hypertrophy, and Bauer's squid incision for lobule prominence. The complication rate was 9.2% including early hematoma, hypersensitivity, and suture extrusion. Unfavorable results occurred in 4% including partial recurrence, overcorrection, and undercorrection. To reduce unfavorable results and avoid recurrence, we propose the use of a classification and treatment algorithm in preoperative evaluation of prominent ear. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Association of Urinary Tract Infection in Married Women Presenting with Urinary Incontinence in a Hospital based Population.

PubMed

Subramaniam, Jayakumar; Eswara, Shilpalakshmiprasad; Yesudhason, Bineshlal

2016-03-01

Urinary incontinence (UI) is increasingly recognized as a significant health problem, which remains a hygienic as well as social problem. Women have higher risk of developing incontinence in their lifetime compared with men. Urinary tract infection can increase the incidence of incontinence. Present study was undertaken to assess the association of UTI in married women who presented with UI. The present study was aimed to identify the patients (married women) with complaints of UI and determining its association with UTI; and to identify the causative organism for the UTI along with its antimicrobial susceptibility pattern. This is a cross-sectional, non-randomized study of 107 married women with UI, who attended outpatient department in our hospital. Mid-stream urine (MSU) samples were collected from these patients with positive history of incontinence. Screening of urine for significant bacteriuria and culture to identify the etiological agents were performed followed by evaluation of their antimicrobial susceptibility profiles using Kirby Bauer disc diffusion method. Overall 25.2% of patients with incontinence had a positive urine culture. History of UTI was elicited in around 38.3% of patients, among which 15% had positive urine culture and 10.3% of the patients who did not have a history had positive culture. Escherichia coli was the commonest causative organism (66.6) causing UTI, followed by Enterococcus spp. (22.3%), Klebsiella pneumoniae (7.4%) and Proteus mirabilis (3.7%). The antimicrobial susceptibility pattern for Escherichia coli showed high sensitivity to Nitrofurantoin (94.4%) and high resistance to Ampicillin (94.4%). Our study revealed one in every four incontinent patients had UTI and almost half of them suffered from previous episodes of UTI. Thus appropriate correction of the existing UTI can help in the treatment of UI.

Linearly scaling and almost Hamiltonian dielectric continuum molecular dynamics simulations through fast multipole expansions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lorenzen, Konstantin; Mathias, Gerald; Tavan, Paul, E-mail: tavan@physik.uni-muenchen.de

2015-11-14

Hamiltonian Dielectric Solvent (HADES) is a recent method [S. Bauer et al., J. Chem. Phys. 140, 104103 (2014)] which enables atomistic Hamiltonian molecular dynamics (MD) simulations of peptides and proteins in dielectric solvent continua. Such simulations become rapidly impractical for large proteins, because the computational effort of HADES scales quadratically with the number N of atoms. If one tries to achieve linear scaling by applying a fast multipole method (FMM) to the computation of the HADES electrostatics, the Hamiltonian character (conservation of total energy, linear, and angular momenta) may get lost. Here, we show that the Hamiltonian character of HADESmore » can be almost completely preserved, if the structure-adapted fast multipole method (SAMM) as recently redesigned by Lorenzen et al. [J. Chem. Theory Comput. 10, 3244-3259 (2014)] is suitably extended and is chosen as the FMM module. By this extension, the HADES/SAMM forces become exact gradients of the HADES/SAMM energy. Their translational and rotational invariance then guarantees (within the limits of numerical accuracy) the exact conservation of the linear and angular momenta. Also, the total energy is essentially conserved—up to residual algorithmic noise, which is caused by the periodically repeated SAMM interaction list updates. These updates entail very small temporal discontinuities of the force description, because the employed SAMM approximations represent deliberately balanced compromises between accuracy and efficiency. The energy-gradient corrected version of SAMM can also be applied, of course, to MD simulations of all-atom solvent-solute systems enclosed by periodic boundary conditions. However, as we demonstrate in passing, this choice does not offer any serious advantages.« less

Antibiotic resistance pattern and plasmid profiling of thermotolerant Escherichia coli isolates in drinking water.

PubMed

Subba, P; Joshi, D R; Bhatta, D R

2013-01-01

Antibiotic resistant Escherichia coli is potential source of transmission of resistance to other water borne pathogens where plasmid borne resistance is most significant. Drinking water samples were collected from different water sources: that is to say- tap, well and spring from different places of Kathmandu where E. coli and thermotolerant E. coli were isolated using membrane filtration technique. Antibiotic susceptibility was determined using a modified Kirby Bauer disc diffusion method and thermotolerant E. coli isolates from tap water were subjected for plasmid profiling. Type of water sources were not associated with the presence of coliform (P=0.155) and thermotolerant coliform (P=0.235) but the significant association was observed in thermotolerant coliform and thermotolerant E. coli for all sources tap (P=0.029), well (P=0.028), spring (P=0.05) but total coliform and E. coli association was found for well (P=0.01). All E. coli and thermotolerant E. coli isolates were susceptible to Ofloxacin, Chloramphenicol and Cotrimixazole. Resistance to Cefexime, Amikacin, Nalidixic acid, Amoxicillin, Tetracycline were 17 (54.8%), 9 (29%), 11 (35.5%), 25 (80.6%), 29 (93.5%) and 19 (57.6%), 12 (36.4%), 13 (39.4%), 31 (94%), 33 (100%) was observed in E. coli and thermotolerant E. coli respectively where 25 (75.8%) thermotolerant E. coli and 22 (70.9%) E. coli were observed with multiple drug resistance patterns. Single band of plasmid were observed in three MDRs and one non-MDR isolates and size varied from 2kb to >10kb. All Nalidixic acid resistant thermotolerant E. coli were found to harbor a plasmid. Presence of plasmid in Nalidixic acid resistant thermotolerant E. coli heightens public health issue and the need of monitoring Quinolone resistance bacteria in environment.

Genetic Diversity and Antibiotic Resistance of Escherichia coli Isolates from Different Leafy Green Production Systems.

PubMed

Jongman, Mosimanegape; Korsten, Lise

2016-11-01

Foodborne disease outbreaks linked to contaminated irrigation water and fresh produce are a public health concern. The presence of Escherichia coli isolates from irrigation water and leafy green vegetables in different food production systems (large commercial farms, small-scale farms, and homestead gardens) was investigated. The prevalence of antibiotic resistance and virulence in these isolates was further assessed, and links between water source and irrigated crops were identified using antimicrobial and genotypic analyses. Presumptive E. coli isolates were identified by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, and identities were confirmed by PCR using the uidA gene. Antimicrobial susceptibility was evaluated with the Kirby Bauer disk diffusion test; the presence of virulence genes was determined with enterobacterial repetitive intergenic consensus PCR assays. Of the 130 E. coli isolates from water (n =60) and leafy green vegetables (n =70), 19 (14.6%) were resistant to one antibiotic (tetracycline) and 92 (70.7%) were resistant to various antibiotics (including ampicillin, cefoxitin, and nalidixic acid). All E. coli isolates were susceptible to ceftriaxone and gentamicin. The virulence gene stx 2 was detected in E. coli isolates from irrigation water (8 [13.3%] of 60 isolates) and cabbages (3 [7.5%] of 40), but the virulence genes eae and stx 1 were not detected in any tested isolates from irrigation water and fresh produce samples. The prevalence of multidrug-resistant E. coli was lower in isolates from GLOBALG.A.P.-certified farms than in isolates from noncertified commercial and small-scale farms and homestead gardens. A link between the E. coli isolates from irrigation water sources and leafy green vegetables was established with phenotypic (antimicrobial) and genotypic (DNA fingerprinting) analyses. However, a link between virulence genes and the prevalence of antimicrobial resistance could not be established.

Occurrence of antibiotic resistance and characterization of resistant genes and integrons in Enterobacteriaceae isolated from integrated fish farms south China

USGS Publications Warehouse

Su, Hao-Chang; Ying, Guang-Guo; Tao, Ran; Zhang, Rui-Quan; Fogarty, Lisa R.; Kolpin, Dana W.

2011-01-01

Antibiotics are still widely applied in animal husbandry to prevent diseases and used as feed additives to promote animal growth. This could result in antibiotic resistance to bacteria and antibiotic residues in animals. In this paper, Enterobacteriaceae isolated from four integrated fish farms in Zhongshan, South China were tested for antibiotic resistance, tetracycline resistance genes, sulfonamide resistance genes, and class 1 integrons. The Kirby-Bauer disk diffusion method and polymerase chain reaction (PCR) assays were carried out to test antibiotic susceptibility and resistance genes, respectively. Relatively high antibiotic resistance frequencies were found, especially for ampicillin (80%), tetracycline (52%), and trimethoprim (50%). Out of 203 Enterobacteriaceae isolates, 98.5% were resistant to one or more antibiotics tested. Multiple antibiotic resistance (MAR) was found highest in animal manures with a MAR index of 0.56. Tetracycline resistance genes (tet(A), tet(C)) and sulfonamide resistance genes (sul2) were detected in more than 50% of the isolates. The intI1 gene was found in 170 isolates (83.7%). Both classic and non-classic class 1 integrons were found. Four genes, aadA5, aadA22, dfr2, and dfrA17, were detected. To our knowledge, this is the first report for molecular characterization of antibiotic resistance genes in Enterobacteriaceae isolated from integrated fish farms in China and the first time that gene cassette array dfrA17-aadA5 has been detected in such fish farms. Results of this study indicated that fish farms may be a reservoir of highly diverse and abundant antibiotic resistant genes and gene cassettes. Integrons may play a key role in multiple antibiotic resistances posing potential health risks to the general public and aquaculture.

The Most Cut-Resistant Neck Guard for Preventing Lacerations to the Neck

PubMed Central

Loyd, Andre M.; Berglund, Lawrence; Twardowski, Casey P.; Stuart, Michael B.; Smith, Aynsley M.; Gaz, Daniel V.; Krause, David A.; An, Kai-Nan; Stuart, Michael J.

2017-01-01

Objective To evaluate the effectiveness of a variety of neck guard brands when contacted by a sharpened hockey skate blade. Design Analytic experimental. Setting Laboratory. Participants Neck surrogate. Interventions Forty-six samples of 14 different types of neck guards were tested on a custom-made laceration machine using a neck surrogate. Closed-cell polyethylene foam was placed between the neck surrogate and the protective device. Main Outcome Measures The effectiveness of the neck guard was evaluated by observation of the foam after the simulated slicing action of the skate blade. Two sets of tests were performed on each device sample including low and high force. For low-force tests, initial compression loads of 100, 200, and 300 N were applied between the neck surrogate for each of 2 orientations of the blade at 45 and 90 degrees. For high-force tests, representing a more severe simulation, the applied load was increased to 600 N and a blade angle fixed at 45 degrees. All tests were performed at a blade speed of 5 m/s. Results Only 1 product, the Bauer N7 Nectech, failed during the 300-N compression tests. All of the neck guards failed during 600-N test condition except for the Skate Armor device and 1 of the 3 Reebok 11K devices. Conclusions A skate blade angle of 45 degrees increased the likelihood of a neck laceration compared with a skate blade angle of 90 degrees due to decreased contact area. Damage to the neck guard is not an indicator of the cut resistance of a neck guard. Neck protectors with Spectra fibers were the most cut resistant. Clinical Relevance The study provides data for the selection of neck guards and neck guard materials that can reduce lacerations to the neck. PMID:24949830

Synthesis, characterization, and biological activity of some novel Schiff bases and their Co(II) and Ni(II) complexes: A new route for Co3O4 and NiO nanoparticles for photocatalytic degradation of methylene blue dye

NASA Astrophysics Data System (ADS)

Nassar, Mostafa Y.; Aly, Hisham M.; Abdelrahman, Ehab A.; Moustafa, Moustafa E.

2017-09-01

Six novel Co(II) and Ni(II)-triazole Schiff base complexes have been successfully synthesized by refluxing the prepared triazole Schiff bases with CoCl2·6H2O or NiCl2·6H2O. The Schiff base ligands were prepared through condensation of 3-R-4-amino-5-hydrazino-1,2,4-triazole with dibenzoylmethane [Rdbnd H, CH3, and CH2CH3; namely, L1, L2, and L3, respectively]. The prepared Co(II) and Ni(II) complexes have been identified using elemental analysis, FT-IR, UV-Vis, magnetic moment, conductivity, and thermal analysis. On the basis of the conductance results, it was concluded that all the prepared complexes are nonelectrolytes. Interestingly, the prepared Co(II) and Ni(II) complexes were employed as precursors for producing of Co3O4 and NiO nanoparticles, respectively. The produced nanostructures have been identified by XRD, HR-TEM, FT-IR and UV-Vis spectra. The produced nanoparticles revealed good photocatalytic activity for the degradation of methylene blue dye under UV illumination in presence of hydrogen peroxide. The percent of degradation was estimated to be 55.71% in 420.0 min and 90.43% in 360.0 min for Co3O4 and NiO, respectively. Moreover, the synthesized complexes, nano-sized Co3O4, and NiO products have been examined, employing modified Bauer- Kirby method, for antifungal (Candida albicans and Aspergillus flavus) and antibacterial (Staphylococcus aureus and Escherichia coli) activities.

Physico-chemical Analysis, Microbial Isolation, Sensitivity Test of the Isolates and Solar Disinfection of Water Running in Community Taps and River Kandutura in Nakuru North Sub-county, Kenya

PubMed Central

Waithaka, Paul N; Maingi, John Muthini; Nyamache, Anthony Kebira

2015-01-01

Nakuru North sub-county is a peri-urban area which has both dry and wet seasons. Its residents rely mostly on untreated water sources for daily water needs due to unreliable water supply from the urban council. However, this water has not been evaluated on its quality despite residents solely depending on it. This study was aimed at determining the physico-chemical and bacteriological quality of water drawn from River Kandutura and water taps in Nakuru North sub-county. In addition, the study was aimed at carrying out sensitivity test of the isolates to antibiotics and determining effectiveness of solar disinfection in water treatment. A total of 510 water samples; river (255) and taps (255) were collected and analyzed between January and December 2013. Antimicrobial sensitivity test was carried out using Kirby Bauer disk diffusion test. Out of five hundred and ten (510) samples examined for microorganisms, 36.86 % (188/510) were positive for E. coli, Shigella and Salmonella. Water used by Nakuru North sub-county residents is highly contaminated thus posing public health risk. Solar disinfection experiment indicated a possibility of effective decontamination of water up on exposure to sun light for 3-5 h. E. coli showed the highest resistance (26.3 %) followed by Salmonella (17.4 %) while Shigella showed the least (17.1 %). However, there was no significant deference (p=0.98) in resistance among total coliforms, Total heterotrophic and Salmonella at 0.05 level of significant. There is a need to enforce laws and policies on proper waste disposal as part of water pollution control. PMID:26464611

Methicillin-Resistant Staphylococcus aureus from Brazilian Dairy Farms and Identification of Novel Sequence Types.

PubMed

Oliveira, C J B; Tiao, N; de Sousa, F G C; de Moura, J F P; Santos Filho, L; Gebreyes, W A

2016-03-01

The aim of this study was to investigate the phenotypic and genotypic diversity and anti-microbial resistance among staphylococci of dairy herds that originated from Paraiba State, north-eastern Brazil, a region where such studies are rare. Milk samples (n = 552) were collected from 15 dairy farms. Isolates were evaluated for anti-microbial susceptibility by Kirby-Bauer disc diffusion method. Confirmation of methicillin-resistant Staphylococcus aureus (MRSA) was performed using multiplex PCR targeting mecA and nuc genes in addition to phenotypic assay based on PBP-2a latex agglutination. Clonal relatedness of isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) genotyping. Staphylococci were detected in 269 (49%) of the samples. Among these, 65 (24%) were S. aureus. The remaining 204 isolates were either coagulase-negative staphylococci (n = 188; 70%) or coagulase positive other than S. aureus (n = 16; 6%). Staphylococci were cultured in seven (35%) of the 20 hand swab samples, from which five isolates were S. aureus. The isolates were most commonly resistant against penicillin (43%), ampicillin (38%) and oxacillin (27%). The gene mecA was detected in 21 S. aureus from milk and in one isolate from a milker's hand. None of the isolates were resistant to vancomycin. PFGE findings showed high clonal diversity among the isolates. Based on MLST, we identified a total of 11 different sequence types (STs 1, 5, 6, 83, 97, 126, 1583, 1622, 1623, 1624 and 1625) with four novel STs (ST1622-ST1625). The findings show that MRSA is prevalent in milk from semi-extensive dairy cows in north-eastern Brazil, and further investigation on its extent in various types of milk production systems and the farm-to-table continuum is warranted. © 2015 Blackwell Verlag GmbH.

Structure of the metal-dependent deacetylase LpxC from Yersinia enterocolitica complexed with the potent inhibitor CHIR-090 .

PubMed

Cole, Kathryn E; Gattis, Samuel G; Angell, Heather D; Fierke, Carol A; Christianson, David W

2011-01-18

The first committed step of lipid A biosynthesis is catalyzed by UDP-(3-O-((R)-3-hydroxymyristoyl))-N-acetylglucosamine deacetylase, a metal-dependent deacetylase also known as LpxC. Because lipid A is essential for bacterial viability, the inhibition of LpxC is an appealing therapeutic strategy for the treatment of Gram-negative bacterial infections. Here we report the 1.79 Å resolution X-ray crystal structure of LpxC from Yersinia enterocolitica (YeLpxC) complexed with the potent hydroxamate inhibitor CHIR-090. This enzyme is a nearly identical orthologue of LpxC from Yersinia pestis (99.7% sequence identity), the pathogen that causes bubonic plague. Similar to the inhibition of LpxC from Escherichia coli, CHIR-090 inhibits YeLpxC via a two-step slow, tight-binding mechanism with an apparent K(i) of 0.54 ± 0.14 nM followed by conversion of the E·I to E·I* species with a rate constant of 0.11 ± 0.01 min(-1). The structure of the LpxC complex with CHIR-090 shows that the inhibitor hydroxamate group chelates the active site zinc ion, and the "tail" of the inhibitor binds in the hydrophobic tunnel in the active site. This hydrophobic tunnel is framed by a βαβ subdomain that exhibits significant conformational flexibility as it accommodates inhibitor binding. CHIR-090 displays a 27 mm zone of inhibition against Y. enterocolitica in a Kirby-Bauer antibiotic assay, which is comparable to its reported activity against other Gram-negative species including E. coli and Pseudomonas aeruginosa. This study demonstrates that the inhibition of LpxC should be explored as a potential therapeutic and/or prophylatic response to infection by weaponized Yersinia species.

CIMP status of interval colon cancers: another piece to the puzzle.

PubMed

Arain, Mustafa A; Sawhney, Mandeep; Sheikh, Shehla; Anway, Ruth; Thyagarajan, Bharat; Bond, John H; Shaukat, Aasma

2010-05-01

Colon cancers diagnosed in the interval after a complete colonoscopy may occur due to limitations of colonoscopy or due to the development of new tumors, possibly reflecting molecular and environmental differences in tumorigenesis resulting in rapid tumor growth. In a previous study from our group, interval cancers (colon cancers diagnosed within 5 years of a complete colonoscopy) were almost four times more likely to demonstrate microsatellite instability (MSI) than non-interval cancers. In this study we extended our molecular analysis to compare the CpG island methylator phenotype (CIMP) status of interval and non-interval colorectal cancers and investigate the relationship between the CIMP and MSI pathways in the pathogenesis of interval cancers. We searched our institution's cancer registry for interval cancers, defined as colon cancers that developed within 5 years of a complete colonoscopy. These were frequency matched in a 1:2 ratio by age and sex to patients with non-interval cancers (defined as colon cancers diagnosed on a patient's first recorded colonoscopy). Archived cancer specimens for all subjects were retrieved and tested for CIMP gene markers. The MSI status of subjects identified between 1989 and 2004 was known from our previous study. Tissue specimens of newly identified cases and controls (between 2005 and 2006) were tested for MSI. There were 1,323 cases of colon cancer diagnosed over the 17-year study period, of which 63 were identified as having interval cancer and matched to 131 subjects with non-interval cancer. Study subjects were almost all Caucasian men. CIMP was present in 57% of interval cancers compared to 33% of non-interval cancers (P=0.004). As shown previously, interval cancers were more likely than non-interval cancers to occur in the proximal colon (63% vs. 39%; P=0.002), and have MSI 29% vs. 11%, P=0.004). In multivariable logistic regression model, proximal location (odds ratio (OR) 1.85; 95% confidence interval (CI) 1.01-3.8), MSI (OR 2.7; 95% CI 1.1-6.8) and CIMP (OR 2.41; 95% CI 1.2-4.9) were independently associated with interval cancers. CIMP was associated with interval cancers independent of MSI status. There was no difference in 5-year survival between the two groups. Interval cancers are more likely to arise in the proximal colon and demonstrate CIMP, which suggests there may be differences in biology between these and non-interval CRC. Additional studies are needed to determine whether interval cancers arise as a result of missed lesions or accelerated neoplastic progression.

Prevalence of QT interval prolongation in patients admitted to cardiac care units and frequency of subsequent administration of QT interval-prolonging drugs: a prospective, observational study in a large urban academic medical center in the US.

PubMed

Tisdale, James E; Wroblewski, Heather A; Overholser, Brian R; Kingery, Joanna R; Trujillo, Tate N; Kovacs, Richard J

2012-06-01

Cardiac arrest due to torsades de pointes (TdP) is a rare but catastrophic event in hospitals. Patients admitted to cardiac units are at higher risk of drug-induced QT interval prolongation and TdP, due to a preponderance of risk factors. Few data exist regarding the prevalence of QT interval prolongation in patients admitted to cardiac units or the frequency of administering QT interval-prolonging drugs to patients presenting with QT interval prolongation. The aim of this study was to determine the prevalence of Bazett's-corrected QT (QT(c)) interval prolongation upon admission to cardiac units and the proportion of patients presenting with QT(c) interval prolongation who are subsequently administered QT interval-prolonging drugs during hospitalization. This was a prospective, observational study conducted over a 1-year period (October 2008-October 2009) in 1159 consecutive patients admitted to two cardiac units in a large urban academic medical centre located in Indianapolis, IN, USA. Patients were enrolled into the study at the time of admission to the hospital and were followed daily during hospitalization. Exclusion criteria were age <18 years, ECG rhythm of complete ventricular pacing, and patient designation as 'outpatient' in a bed and/or duration of stay <24 hours. Data collected included demographic information, past medical history, daily progress notes, medication administration records, laboratory data, ECGs, telemetry monitoring strips and diagnostic reports. All patients underwent continuous cardiac telemetry monitoring and/or had a baseline 12-lead ECG obtained within 4 hours of admission. QT intervals were determined manually from lead II of 12-lead ECGs or from continuous lead II telemetry monitoring strips. QT(c) interval prolongation was defined as ≥470 ms for males and ≥480 ms for females. In both males and females, QT(c) interval >500 ms was considered abnormally high. A medication was classified as QT interval-prolonging if there were published data indicating that the drug causes QT interval prolongation and/or TdP. Study endpoints were (i) prevalence of QT(c) interval prolongation upon admission to the Cardiac Medical Critical Care Unit (CMCCU) or an Advanced Heart Care Unit (AHCU); (ii) proportion of patients admitted to the CMCCU/AHCU with QT(c) interval prolongation who subsequently were administered QT interval-prolonging drugs during hospitalization; (iii) the proportion of these higher-risk patients in whom TdP risk factor monitoring was performed; (iv) proportion of patients with QT(c) interval prolongation who subsequently received QT-prolonging drugs and who experienced further QT(c) interval prolongation. Of 1159 patients enrolled, 259 patients met exclusion criteria, resulting in a final sample size of 900 patients. mean (± SD) age, 65 ± 15 years; female, 47%; Caucasian, 70%. Admitting diagnoses: heart failure (22%), myocardial infarction (16%), atrial fibrillation (9%), sudden cardiac arrest (3%). QT(c) interval prolongation was present in 27.9% of patients on admission; 18.2% had QT(c) interval >500 ms. Of 251 patients admitted with QT(c) interval prolongation, 87 (34.7%) were subsequently administered QT interval-prolonging drugs. Of 166 patients admitted with QT(c) interval >500 ms, 70 (42.2%) were subsequently administered QT interval-prolonging drugs; additional QT(c) interval prolongation ≥60 ms occurred in 57.1% of these patients. QT(c) interval prolongation is common among patients admitted to cardiac units. QT interval-prolonging drugs are commonly prescribed to patients presenting with QT(c) interval prolongation.

A framework for interval-valued information system

NASA Astrophysics Data System (ADS)

Yin, Yunfei; Gong, Guanghong; Han, Liang

2012-09-01

Interval-valued information system is used to transform the conventional dataset into the interval-valued form. To conduct the interval-valued data mining, we conduct two investigations: (1) construct the interval-valued information system, and (2) conduct the interval-valued knowledge discovery. In constructing the interval-valued information system, we first make the paired attributes in the database discovered, and then, make them stored in the neighbour locations in a common database and regard them as 'one' new field. In conducting the interval-valued knowledge discovery, we utilise some related priori knowledge and regard the priori knowledge as the control objectives; and design an approximate closed-loop control mining system. On the implemented experimental platform (prototype), we conduct the corresponding experiments and compare the proposed algorithms with several typical algorithms, such as the Apriori algorithm, the FP-growth algorithm and the CLOSE+ algorithm. The experimental results show that the interval-valued information system method is more effective than the conventional algorithms in discovering interval-valued patterns.

Inconsistencies in Numerical Simulations of Dynamical Systems Using Interval Arithmetic

NASA Astrophysics Data System (ADS)

Nepomuceno, Erivelton G.; Peixoto, Márcia L. C.; Martins, Samir A. M.; Rodrigues, Heitor M.; Perc, Matjaž

Over the past few decades, interval arithmetic has been attracting widespread interest from the scientific community. With the expansion of computing power, scientific computing is encountering a noteworthy shift from floating-point arithmetic toward increased use of interval arithmetic. Notwithstanding the significant reliability of interval arithmetic, this paper presents a theoretical inconsistency in a simulation of dynamical systems using a well-known implementation of arithmetic interval. We have observed that two natural interval extensions present an empty intersection during a finite time range, which is contrary to the fundamental theorem of interval analysis. We have proposed a procedure to at least partially overcome this problem, based on the union of the two generated pseudo-orbits. This paper also shows a successful case of interval arithmetic application in the reduction of interval width size on the simulation of discrete map. The implications of our findings on the reliability of scientific computing using interval arithmetic have been properly addressed using two numerical examples.

40 CFR 1065.672 - Drift correction.

Code of Federal Regulations, 2013 CFR

2013-07-01

... interval gas analyzer response to the span gas concentration. x postspan = post-test interval gas analyzer... = post-test interval gas analyzer response to the zero gas concentration. Example: x refzero = 0 µmol/mol... occurred before one or more previous test intervals. (4) For any post-test interval concentrations, use...

40 CFR 1065.672 - Drift correction.

Code of Federal Regulations, 2010 CFR

2010-07-01

... interval gas analyzer response to the span gas concentration. x postspan = post-test interval gas analyzer... = post-test interval gas analyzer response to the zero gas concentration. Example: x refzero = 0 µmol/mol... occurred before one or more previous test intervals. (4) For any post-test interval concentrations, use...

40 CFR 1065.672 - Drift correction.

Code of Federal Regulations, 2014 CFR

2014-07-01

... interval gas analyzer response to the span gas concentration. x postspan = post-test interval gas analyzer... = post-test interval gas analyzer response to the zero gas concentration. Example: x refzero = 0 µmol/mol... occurred before one or more previous test intervals. (4) For any post-test interval concentrations, use...

40 CFR 1065.672 - Drift correction.

Code of Federal Regulations, 2012 CFR

2012-07-01

... interval gas analyzer response to the span gas concentration. x postspan = post-test interval gas analyzer... = post-test interval gas analyzer response to the zero gas concentration. Example: x refzero = 0 µmol/mol... occurred before one or more previous test intervals. (4) For any post-test interval concentrations, use...

40 CFR 1065.672 - Drift correction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... interval gas analyzer response to the span gas concentration. x postspan = post-test interval gas analyzer... = post-test interval gas analyzer response to the zero gas concentration. Example: x refzero = 0 µmol/mol... occurred before one or more previous test intervals. (4) For any post-test interval concentrations, use...

An Introduction to Confidence Intervals for Both Statistical Estimates and Effect Sizes.

ERIC Educational Resources Information Center

Capraro, Mary Margaret

This paper summarizes methods of estimating confidence intervals, including classical intervals and intervals for effect sizes. The recent American Psychological Association (APA) Task Force on Statistical Inference report suggested that confidence intervals should always be reported, and the fifth edition of the APA "Publication Manual"…

Bootstrap Confidence Intervals for Ordinary Least Squares Factor Loadings and Correlations in Exploratory Factor Analysis

ERIC Educational Resources Information Center

Zhang, Guangjian; Preacher, Kristopher J.; Luo, Shanhong

2010-01-01

This article is concerned with using the bootstrap to assign confidence intervals for rotated factor loadings and factor correlations in ordinary least squares exploratory factor analysis. Coverage performances of "SE"-based intervals, percentile intervals, bias-corrected percentile intervals, bias-corrected accelerated percentile…

An Event Restriction Interval Theory of Tense

ERIC Educational Resources Information Center

Beamer, Brandon Robert

2012-01-01

This dissertation presents a novel theory of tense and tense-like constructions. It is named after a key theoretical component of the theory, the event restriction interval. In Event Restriction Interval (ERI) Theory, sentences are semantically evaluated relative to an index which contains two key intervals, the evaluation interval and the event…

Chosen interval methods for solving linear interval systems with special type of matrix

NASA Astrophysics Data System (ADS)

Szyszka, Barbara

2013-10-01

The paper is devoted to chosen direct interval methods for solving linear interval systems with special type of matrix. This kind of matrix: band matrix with a parameter, from finite difference problem is obtained. Such linear systems occur while solving one dimensional wave equation (Partial Differential Equations of hyperbolic type) by using the central difference interval method of the second order. Interval methods are constructed so as the errors of method are enclosed in obtained results, therefore presented linear interval systems contain elements that determining the errors of difference method. The chosen direct algorithms have been applied for solving linear systems because they have no errors of method. All calculations were performed in floating-point interval arithmetic.

Extended Task Space Control for Robotic Manipulators

NASA Technical Reports Server (NTRS)

Backes, Paul G. (Inventor); Long, Mark K. (Inventor)

1996-01-01

The invention is a method of operating a robot in successive sampling intervals to perform a task, the robot having joints and joint actuators with actuator control loops, by decomposing the task into behavior forces, accelerations, velocities and positions of plural behaviors to be exhibited by the robot simultaneously, computing actuator accelerations of the joint actuators for the current sampling interval from both behavior forces, accelerations velocities and positions of the current sampling interval and actuator velocities and positions of the previous sampling interval, computing actuator velocities and positions of the joint actuators for the current sampling interval from the actuator velocities and positions of the previous sampling interval, and, finally, controlling the actuators in accordance with the actuator accelerations, velocities and positions of the current sampling interval. The actuator accelerations, velocities and positions of the current sampling interval are stored for use during the next sampling interval.

Ratio-based lengths of intervals to improve fuzzy time series forecasting.

PubMed

Huarng, Kunhuang; Yu, Tiffany Hui-Kuang

2006-04-01

The objective of this study is to explore ways of determining the useful lengths of intervals in fuzzy time series. It is suggested that ratios, instead of equal lengths of intervals, can more properly represent the intervals among observations. Ratio-based lengths of intervals are, therefore, proposed to improve fuzzy time series forecasting. Algebraic growth data, such as enrollments and the stock index, and exponential growth data, such as inventory demand, are chosen as the forecasting targets, before forecasting based on the various lengths of intervals is performed. Furthermore, sensitivity analyses are also carried out for various percentiles. The ratio-based lengths of intervals are found to outperform the effective lengths of intervals, as well as the arbitrary ones in regard to the different statistical measures. The empirical analysis suggests that the ratio-based lengths of intervals can also be used to improve fuzzy time series forecasting.

An interval model updating strategy using interval response surface models

NASA Astrophysics Data System (ADS)

Fang, Sheng-En; Zhang, Qiu-Hu; Ren, Wei-Xin

2015-08-01

Stochastic model updating provides an effective way of handling uncertainties existing in real-world structures. In general, probabilistic theories, fuzzy mathematics or interval analyses are involved in the solution of inverse problems. However in practice, probability distributions or membership functions of structural parameters are often unavailable due to insufficient information of a structure. At this moment an interval model updating procedure shows its superiority in the aspect of problem simplification since only the upper and lower bounds of parameters and responses are sought. To this end, this study develops a new concept of interval response surface models for the purpose of efficiently implementing the interval model updating procedure. The frequent interval overestimation due to the use of interval arithmetic can be maximally avoided leading to accurate estimation of parameter intervals. Meanwhile, the establishment of an interval inverse problem is highly simplified, accompanied by a saving of computational costs. By this means a relatively simple and cost-efficient interval updating process can be achieved. Lastly, the feasibility and reliability of the developed method have been verified against a numerical mass-spring system and also against a set of experimentally tested steel plates.

Statistics of return intervals between long heartbeat intervals and their usability for online prediction of disorders

NASA Astrophysics Data System (ADS)

Bogachev, Mikhail I.; Kireenkov, Igor S.; Nifontov, Eugene M.; Bunde, Armin

2009-06-01

We study the statistics of return intervals between large heartbeat intervals (above a certain threshold Q) in 24 h records obtained from healthy subjects. We find that both the linear and the nonlinear long-term memory inherent in the heartbeat intervals lead to power-laws in the probability density function PQ(r) of the return intervals. As a consequence, the probability WQ(t; Δt) that at least one large heartbeat interval will occur within the next Δt heartbeat intervals, with an increasing elapsed number of intervals t after the last large heartbeat interval, follows a power-law. Based on these results, we suggest a method of obtaining a priori information about the occurrence of the next large heartbeat interval, and thus to predict it. We show explicitly that the proposed method, which exploits long-term memory, is superior to the conventional precursory pattern recognition technique, which focuses solely on short-term memory. We believe that our results can be straightforwardly extended to obtain more reliable predictions in other physiological signals like blood pressure, as well as in other complex records exhibiting multifractal behaviour, e.g. turbulent flow, precipitation, river flows and network traffic.

Reference Intervals of Common Clinical Chemistry Analytes for Adults in Hong Kong.

PubMed

Lo, Y C; Armbruster, David A

2012-04-01

Defining reference intervals is a major challenge because of the difficulty in recruiting volunteers to participate and testing samples from a significant number of healthy reference individuals. Historical literature citation intervals are often suboptimal because they're be based on obsolete methods and/or only a small number of poorly defined reference samples. Blood donors in Hong Kong gave permission for additional blood to be collected for reference interval testing. The samples were tested for twenty-five routine analytes on the Abbott ARCHITECT clinical chemistry system. Results were analyzed using the Rhoads EP evaluator software program, which is based on the CLSI/IFCC C28-A guideline, and defines the reference interval as the 95% central range. Method specific reference intervals were established for twenty-five common clinical chemistry analytes for a Chinese ethnic population. The intervals were defined for each gender separately and for genders combined. Gender specific or combined gender intervals were adapted as appropriate for each analyte. A large number of healthy, apparently normal blood donors from a local ethnic population were tested to provide current reference intervals for a new clinical chemistry system. Intervals were determined following an accepted international guideline. Laboratories using the same or similar methodologies may adapt these intervals if deemed validated and deemed suitable for their patient population. Laboratories using different methodologies may be able to successfully adapt the intervals for their facilities using the reference interval transference technique based on a method comparison study.

Effect of the time interval between fusion and activation on epigenetic reprogramming and development of bovine somatic cell nuclear transfer embryos.

PubMed

Liu, Jun; Wang, Yongsheng; Su, Jianmin; Wang, Lijun; Li, Ruizhe; Li, Qian; Wu, Yongyan; Hua, Song; Quan, Fusheng; Guo, Zekun; Zhang, Yong

2013-04-01

Previous studies have shown that the time interval between fusion and activation (FA interval) play an important role in nuclear remodeling and in vitro development of somatic cell nuclear transfer (SCNT) embryos. However, the effects of FA interval on the epigenetic reprogramming and in vivo developmental competence of SCNT embryos remain unknown. In the present study, the effects of different FA intervals (0 h, 2 h, and 4 h) on the epigenetic reprogramming and developmental competence of bovine SCNT embryos were assessed. The results demonstrated that H3 lysine 9 (H3K9ac) levels decreased rapidly after fusion in all three groups. H3K9ac was practically undetectable 2 h after fusion in the 2-h and 4-h FA interval groups. However, H3K9ac was still evidently detectable in the 0-h FA interval group. The H3K9ac levels increased 10 h after fusion in all three groups, but were higher in the 2-h and 4-h FA interval groups than that in the 0-h FA interval group. The methylation levels of the satellite I region in day-7 blastocysts derived from the 2-h or 4-h FA interval groups was similar to that of in vitro fertilization blastocysts and is significantly lower than that of the 0-h FA interval group. SCNT embryos derived from 2-h FA interval group showed higher developmental competence than those from the 0-h and 4-h FA interval groups in terms of cleavage rate, blastocyst formation rate, apoptosis index, and pregnancy and calving rates. Hence, the FA interval is an important factor influencing the epigenetic reprogramming and developmental competence of bovine SCNT embryos.

National Survey of Adult and Pediatric Reference Intervals in Clinical Laboratories across Canada: A Report of the CSCC Working Group on Reference Interval Harmonization.

PubMed

Adeli, Khosrow; Higgins, Victoria; Seccombe, David; Collier, Christine P; Balion, Cynthia M; Cembrowski, George; Venner, Allison A; Shaw, Julie

2017-11-01

Reference intervals are widely used decision-making tools in laboratory medicine, serving as health-associated standards to interpret laboratory test results. Numerous studies have shown wide variation in reference intervals, even between laboratories using assays from the same manufacturer. Lack of consistency in either sample measurement or reference intervals across laboratories challenges the expectation of standardized patient care regardless of testing location. Here, we present data from a national survey conducted by the Canadian Society of Clinical Chemists (CSCC) Reference Interval Harmonization (hRI) Working Group that examines variation in laboratory reference sample measurements, as well as pediatric and adult reference intervals currently used in clinical practice across Canada. Data on reference intervals currently used by 37 laboratories were collected through a national survey to examine the variation in reference intervals for seven common laboratory tests. Additionally, 40 clinical laboratories participated in a baseline assessment by measuring six analytes in a reference sample. Of the seven analytes examined, alanine aminotransferase (ALT), alkaline phosphatase (ALP), and creatinine reference intervals were most variable. As expected, reference interval variation was more substantial in the pediatric population and varied between laboratories using the same instrumentation. Reference sample results differed between laboratories, particularly for ALT and free thyroxine (FT4). Reference interval variation was greater than test result variation for the majority of analytes. It is evident that there is a critical lack of harmonization in laboratory reference intervals, particularly for the pediatric population. Furthermore, the observed variation in reference intervals across instruments cannot be explained by the bias between the results obtained on instruments by different manufacturers. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Xenon does not increase heart rate-corrected cardiac QT interval in volunteers and in patients free of cardiovascular disease.

PubMed

Neukirchen, Martin; Schaefer, Maximilian S; Kern, Carolin; Brett, Sarah; Werdehausen, Robert; Rellecke, Philipp; Reyle-Hahn, Matthias; Kienbaum, Peter

2015-09-01

Impaired cardiac repolarization, indicated by prolonged QT interval, may cause critical ventricular arrhythmias. Many anesthetics increase the QT interval by blockade of rapidly acting potassium rectifier channels. Although xenon does not affect these channels in isolated cardiomyocytes, the authors hypothesized that xenon increases the QT interval by direct and/or indirect sympathomimetic effects. Thus, the authors tested the hypothesis that xenon alters the heart rate-corrected cardiac QT (QTc) interval in anesthetic concentrations. The effect of xenon on the QTc interval was evaluated in eight healthy volunteers and in 35 patients undergoing abdominal or trauma surgery. The QTc interval was recorded on subjects in awake state, after their denitrogenation, and during xenon monoanesthesia (FetXe > 0.65). In patients, the QTc interval was recorded while awake, after anesthesia induction with propofol and remifentanil, and during steady state of xenon/remifentanil anesthesia (FetXe > 0.65). The QTc interval was determined from three consecutive cardiac intervals on electrocardiogram printouts in a blinded manner and corrected with Bazett formula. In healthy volunteers, xenon did not alter the QTc interval (mean difference: +0.11 ms [95% CI, -22.4 to 22.7]). In patients, after anesthesia induction with propofol/remifentanil, no alteration of QTc interval was noted. After propofol was replaced with xenon, the QTc interval remained unaffected (417 ± 32 ms vs. awake: 414 ± 25 ms) with a mean difference of 4.4 ms (95% CI, -4.6 to 13.5). Xenon monoanesthesia in healthy volunteers and xenon/remifentanil anesthesia in patients without clinically relevant cardiovascular disease do not increase QTc interval.

Perceived empty duration between sounds of different lengths: Possible relation with repetition and rhythmic grouping.

PubMed

Kuroda, Tsuyoshi; Tomimatsu, Erika; Grondin, Simon; Miyazaki, Makoto

2016-11-01

We investigated how perceived duration of empty time intervals would be modulated by the length of sounds marking those intervals. Three sounds were successively presented in Experiment 1. Each sound was short (S) or long (L), and the temporal position of the middle sound's onset was varied. The lengthening of each sound resulted in delayed perception of the onset; thus, the middle sound's onset had to be presented earlier in the SLS than in the LSL sequence so that participants perceived the three sounds as presented at equal interonset intervals. In Experiment 2, a short sound and a long sound were alternated repeatedly, and the relative duration of the SL interval to the LS interval was varied. This repeated sequence was perceived as consisting of equal interonset intervals when the onsets of all sounds were aligned at physically equal intervals. If the same onset delay as in the preceding experiment had occurred, participants should have perceived equality between the interonset intervals in the repeated sequence when the SL interval was physically shortened relative to the LS interval. The effects of sound length seemed to be canceled out when the presentation of intervals was repeated. Finally, the perceived duration of the interonset intervals in the repeated sequence was not influenced by whether the participant's native language was French or Japanese, or by how the repeated sequence was perceptually segmented into rhythmic groups.

Sampling Theory and Confidence Intervals for Effect Sizes: Using ESCI To Illustrate "Bouncing"; Confidence Intervals.

ERIC Educational Resources Information Center

Du, Yunfei

This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…

On Some Confidence Intervals for Estimating the Mean of a Skewed Population

ERIC Educational Resources Information Center

Shi, W.; Kibria, B. M. Golam

2007-01-01

A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…

Intertrial interval duration and learning in autistic children.

PubMed Central

Koegel, R L; Dunlap, G; Dyer, K

1980-01-01

This study investigated the influence of intertrial interval duration on the performance of autistic children during teaching situations. The children were taught under the same conditions existing in their regular programs, except that the length of time between trials was systematically manipulated. With both multiple baseline and repeated reversal designs, two lengths of intertrial interval were employed; short intervals with the SD for any given trial presented approximately one second following the reinforcer for the previous trial versus long intervals with the SD presented four or more seconds following the reinforcer for the previous trial. The results showed that: (1) the short intertrial intervals always produced higher levels of correct responding than the long intervals; and (2) there were improving trends in performance and rapid acquisition with the short intertrial intervals, in contrast to minimal or no change with the long intervals. The results are discussed in terms of utilizing information about child and task characteristics in terms of selecting optimal intervals. The data suggest that manipulations made between trials have a large influence on autistic children's learning. PMID:7364701

Interval Timing Is Preserved Despite Circadian Desynchrony in Rats: Constant Light and Heavy Water Studies.

PubMed

Petersen, Christian C; Mistlberger, Ralph E

2017-08-01

The mechanisms that enable mammals to time events that recur at 24-h intervals (circadian timing) and at arbitrary intervals in the seconds-to-minutes range (interval timing) are thought to be distinct at the computational and neurobiological levels. Recent evidence that disruption of circadian rhythmicity by constant light (LL) abolishes interval timing in mice challenges this assumption and suggests a critical role for circadian clocks in short interval timing. We sought to confirm and extend this finding by examining interval timing in rats in which circadian rhythmicity was disrupted by long-term exposure to LL or by chronic intake of 25% D 2 O. Adult, male Sprague-Dawley rats were housed in a light-dark (LD) cycle or in LL until free-running circadian rhythmicity was markedly disrupted or abolished. The rats were then trained and tested on 15- and 30-sec peak-interval procedures, with water restriction used to motivate task performance. Interval timing was found to be unimpaired in LL rats, but a weak circadian activity rhythm was apparently rescued by the training procedure, possibly due to binge feeding that occurred during the 15-min water access period that followed training each day. A second group of rats in LL were therefore restricted to 6 daily meals scheduled at 4-h intervals. Despite a complete absence of circadian rhythmicity in this group, interval timing was again unaffected. To eliminate all possible temporal cues, we tested a third group of rats in LL by using a pseudo-randomized schedule. Again, interval timing remained accurate. Finally, rats tested in LD received 25% D 2 O in place of drinking water. This markedly lengthened the circadian period and caused a failure of LD entrainment but did not disrupt interval timing. These results indicate that interval timing in rats is resistant to disruption by manipulations of circadian timekeeping previously shown to impair interval timing in mice.

Change in Breast Cancer Screening Intervals Since the 2009 USPSTF Guideline.

PubMed

Wernli, Karen J; Arao, Robert F; Hubbard, Rebecca A; Sprague, Brian L; Alford-Teaster, Jennifer; Haas, Jennifer S; Henderson, Louise; Hill, Deidre; Lee, Christoph I; Tosteson, Anna N A; Onega, Tracy

2017-08-01

In 2009, the U.S. Preventive Services Task Force (USPSTF) recommended biennial mammography for women aged 50-74 years and shared decision-making for women aged 40-49 years for breast cancer screening. We evaluated changes in mammography screening interval after the 2009 recommendations. We conducted a prospective cohort study of women aged 40-74 years who received 821,052 screening mammograms between 2006 and 2012 using data from the Breast Cancer Surveillance Consortium. We compared changes in screening intervals and stratified intervals based on whether the mammogram at the end of the interval occurred before or after the 2009 recommendation. Differences in mean interval length by woman-level characteristics were compared using linear regression. The mean interval (in months) minimally decreased after the 2009 USPSTF recommendations. Among women aged 40-49 years, the mean interval decreased from 17.2 months to 17.1 months (difference -0.16%, 95% confidence interval [CI] -0.30 to -0.01). Similar small reductions were seen for most age groups. The largest change in interval length in the post-USPSTF period was declines among women with a first-degree family history of breast cancer (difference -0.68%, 95% CI -0.82 to -0.54) or a 5-year breast cancer risk ≥2.5% (difference -0.58%, 95% CI -0.73 to -0.44). The 2009 USPSTF recommendation did not lengthen the average mammography interval among women routinely participating in mammography screening. Future studies should evaluate whether breast cancer screening intervals lengthen toward biennial intervals following new national 2016 breast cancer screening recommendations, particularly among women less than 50 years of age.

Solar-geophysical activity reports for STIP (study of travelling interplanetary phenomena) Interval 15, 12-21 February 1984 ground-level event and STIP Interval 16, 20 April-4 May 1984 Forbush decrease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coffey, H.E.; Allen, J.H.

1987-07-01

Contents include: solar-geophysical activity reports for STIP Interval XV 12-21 February 1984 ground-level event and STIP interval XVI 20 April-4 May 1984 Forbush decrease; overview of solar-terrestrial physics phenomena for STIP interval XV (12-21 February 1984) and STIP interval XVI (20 April-4 May 1984) (solar optical reports, solar radio events, spacecraft observations, cosmic ray observations, ionosphere, geomagnetism).

Alternative Confidence Interval Methods Used in the Diagnostic Accuracy Studies

PubMed Central

Gülhan, Orekıcı Temel

2016-01-01

Background/Aim. It is necessary to decide whether the newly improved methods are better than the standard or reference test or not. To decide whether the new diagnostics test is better than the gold standard test/imperfect standard test, the differences of estimated sensitivity/specificity are calculated with the help of information obtained from samples. However, to generalize this value to the population, it should be given with the confidence intervals. The aim of this study is to evaluate the confidence interval methods developed for the differences between the two dependent sensitivity/specificity values on a clinical application. Materials and Methods. In this study, confidence interval methods like Asymptotic Intervals, Conditional Intervals, Unconditional Interval, Score Intervals, and Nonparametric Methods Based on Relative Effects Intervals are used. Besides, as clinical application, data used in diagnostics study by Dickel et al. (2010) has been taken as a sample. Results. The results belonging to the alternative confidence interval methods for Nickel Sulfate, Potassium Dichromate, and Lanolin Alcohol are given as a table. Conclusion. While preferring the confidence interval methods, the researchers have to consider whether the case to be compared is single ratio or dependent binary ratio differences, the correlation coefficient between the rates in two dependent ratios and the sample sizes. PMID:27478491

Alternative Confidence Interval Methods Used in the Diagnostic Accuracy Studies.

PubMed

Erdoğan, Semra; Gülhan, Orekıcı Temel

2016-01-01

Background/Aim. It is necessary to decide whether the newly improved methods are better than the standard or reference test or not. To decide whether the new diagnostics test is better than the gold standard test/imperfect standard test, the differences of estimated sensitivity/specificity are calculated with the help of information obtained from samples. However, to generalize this value to the population, it should be given with the confidence intervals. The aim of this study is to evaluate the confidence interval methods developed for the differences between the two dependent sensitivity/specificity values on a clinical application. Materials and Methods. In this study, confidence interval methods like Asymptotic Intervals, Conditional Intervals, Unconditional Interval, Score Intervals, and Nonparametric Methods Based on Relative Effects Intervals are used. Besides, as clinical application, data used in diagnostics study by Dickel et al. (2010) has been taken as a sample. Results. The results belonging to the alternative confidence interval methods for Nickel Sulfate, Potassium Dichromate, and Lanolin Alcohol are given as a table. Conclusion. While preferring the confidence interval methods, the researchers have to consider whether the case to be compared is single ratio or dependent binary ratio differences, the correlation coefficient between the rates in two dependent ratios and the sample sizes.

A scoping review of the psychological responses to interval exercise: is interval exercise a viable alternative to traditional exercise?

PubMed

Stork, Matthew J; Banfield, Laura E; Gibala, Martin J; Martin Ginis, Kathleen A

2017-12-01

While considerable evidence suggests that interval exercise confers numerous physiological adaptations linked to improved health, its psychological consequences and behavioural implications are less clear and the subject of intense debate. The purpose of this scoping review was to catalogue studies investigating the psychological responses to interval exercise in order to identify what psychological outcomes have been assessed, the research methods used, and the results. A secondary objective was to identify research issues and gaps. Forty-two published articles met the review inclusion/exclusion criteria. These studies involved 1258 participants drawn from various active/inactive and healthy/unhealthy populations, and 55 interval exercise protocols (69% high-intensity interval training [HIIT], 27% sprint interval training [SIT], and 4% body-weight interval training [BWIT]). Affect and enjoyment were the most frequently studied psychological outcomes. Post-exercise assessments indicate that overall, enjoyment of, and preferences for interval exercise are equal or greater than for continuous exercise, and participants can hold relatively positive social cognitions regarding interval exercise. Although several methodological issues (e.g., inconsistent use of terminology, measures and protocols) and gaps (e.g., data on adherence and real-world protocols) require attention, from a psychological perspective, the emerging data support the viability of interval exercise as an alternative to continuous exercise.

The temporal organization of behavior on periodic food schedules.

PubMed Central

Reid, A K; Bacha, G; Morán, C

1993-01-01

Various theories of temporal control and schedule induction imply that periodic schedules temporally modulate an organism's motivational states within interreinforcement intervals. This speculation has been fueled by frequently observed multimodal activity distributions created by averaging across interreinforcement intervals. We tested this hypothesis by manipulating the cost associated with schedule-induced activities and the availability of other activities to determine the degree to which (a) the temporal distributions of activities within the interreinforcement interval are fixed or can be temporally displaced, (b) rats can reallocate activities across different interreinforcement intervals, and (c) noninduced activities can substitute for schedule-induced activities. Obtained multimodal activity distributions created by averaging across interreinforcement intervals were not representative of the transitions occurring within individual intervals, so the averaged multimodal distributions should not be assumed to represent changes in the subject's motivational states within the interval. Rather, the multimodal distributions often result from averaging across interreinforcement intervals in which only a single activity occurs. A direct influence of the periodic schedule on the motivational states implies that drinking and running should occur at different periods within the interval, but in three experiments the starting times of drinking and running within interreinforcement intervals were equal. Thus, the sequential pattern of drinking and running on periodic schedules does not result from temporal modulation of motivational states within interreinforcement intervals. PMID:8433061

Identification of low-overpressure interval and its implication to hydrocarbon migration: Case study in the Yanan sag of the Qiongdongnan Basin, South China Sea

PubMed Central

Xu, Qinghai; Shi, Wanzhong; Xie, Yuhong; Wang, Zhenfeng; Li, Xusheng; Tong, Chuanxin

2017-01-01

The Qiongdongnan Basin is a strongly overpressured basin with the maximum pressure coefficient (the ratio of the actual pore pressure versus hydrostatic pressure at the same depth) over 2.27. However, there exists a widespread low-overpressure interval between the strong overpressure intervals in the Yanan Sag of western basin. The mechanisms of the low-overpressure interval are not well understood. Three main approaches, pore pressure test data and well-log analysis, pressure prediction based on the relationship between the deviation of the velocity and the pressure coefficients, and numerical modeling, were employed to illustrate the distribution and evolution of the low-overpressure interval. And we analyzed and explained the phenomenon of the low-overpressure interval that is both underlain and overlain by high overpressure internal. The low-overpressure interval between the strong overpressure intervals can be identified and modelled by drilling data of P-wave sonic and the mud weight, and the numerical modeling using the PetroMod software. Results show that the low-overpressure interval is mainly composed of sandstone sediments. The porosities of sandstone in the low-overpressure interval primarily range from 15%-20%, and the permeabilities range from 10–100 md. Analysis of the geochemical parameters of C1, iC4/nC4, ΔR3, and numerical modeling shows that oil and gas migrated upward into the sandstone in the low-overpressure interval, and then migrated along the sandstone of low-overpressure interval into the Yacheng uplift. The low-overpressure both underlain and overlain by overpressure resulted from the fluids migrating along the sandstones in the low-overpressure interval into the Yacheng uplift since 1.9Ma. The mudstone in the strong overpressure interval is good cap overlain the sandstone of low-overpressure interval, therefore up-dip pinchouts or isolated sandstone in the low-overpressure interval locating the migration path of oil and gas are good plays for hydrocarbon exploration. PMID:28934237

Binary Interval Search: a scalable algorithm for counting interval intersections.

PubMed

Layer, Ryan M; Skadron, Kevin; Robins, Gabriel; Hall, Ira M; Quinlan, Aaron R

2013-01-01

The comparison of diverse genomic datasets is fundamental to understand genome biology. Researchers must explore many large datasets of genome intervals (e.g. genes, sequence alignments) to place their experimental results in a broader context and to make new discoveries. Relationships between genomic datasets are typically measured by identifying intervals that intersect, that is, they overlap and thus share a common genome interval. Given the continued advances in DNA sequencing technologies, efficient methods for measuring statistically significant relationships between many sets of genomic features are crucial for future discovery. We introduce the Binary Interval Search (BITS) algorithm, a novel and scalable approach to interval set intersection. We demonstrate that BITS outperforms existing methods at counting interval intersections. Moreover, we show that BITS is intrinsically suited to parallel computing architectures, such as graphics processing units by illustrating its utility for efficient Monte Carlo simulations measuring the significance of relationships between sets of genomic intervals. https://github.com/arq5x/bits.

Robotic fish tracking method based on suboptimal interval Kalman filter

NASA Astrophysics Data System (ADS)

Tong, Xiaohong; Tang, Chao

2017-11-01

Autonomous Underwater Vehicle (AUV) research focused on tracking and positioning, precise guidance and return to dock and other fields. The robotic fish of AUV has become a hot application in intelligent education, civil and military etc. In nonlinear tracking analysis of robotic fish, which was found that the interval Kalman filter algorithm contains all possible filter results, but the range is wide, relatively conservative, and the interval data vector is uncertain before implementation. This paper proposes a ptimization algorithm of suboptimal interval Kalman filter. Suboptimal interval Kalman filter scheme used the interval inverse matrix with its worst inverse instead, is more approximate nonlinear state equation and measurement equation than the standard interval Kalman filter, increases the accuracy of the nominal dynamic system model, improves the speed and precision of tracking system. Monte-Carlo simulation results show that the optimal trajectory of sub optimal interval Kalman filter algorithm is better than that of the interval Kalman filter method and the standard method of the filter.

[Classification and characteristics of interval cancers in the Principality of Asturias's Breast Cancer Screening Program].

PubMed

Prieto García, M A; Delgado Sevillano, R; Baldó Sierra, C; González Díaz, E; López Secades, A; Llavona Amor, J A; Vidal Marín, B

2013-09-01

To review and classify the interval cancers found in the Principality of Asturias's Breast Cancer Screening Program (PDPCM). A secondary objective was to determine the histological characteristics, size, and stage of the interval cancers at the time of diagnosis. We included the interval cancers in the PDPCM in the period 2003-2007. Interval cancers were classified according to the breast cancer screening program protocol, with double reading without consensus, without blinding, with arbitration. Mammograms were interpreted by 10 radiologists in the PDPCM. A total of 33.7% of the interval cancers could not be classified; of the interval cancers that could be classified, 40.67% were labeled true interval cancers, 31.4% were labeled false negatives on screening, 23.7% had minimal signs, and 4.23% were considered occult. A total of 70% of the interval cancers were diagnosed in the year of the period between screening examinations and 71.7% were diagnosed after subsequent screening. A total of 76.9% were invasive ductal carcinomas, 61.1% were stage II when detected, and 78.7% were larger than 10mm when detected. The rate of interval cancers and the rate of false negatives in the PDPCM are higher than those recommended in the European guidelines. Interval cancers are diagnosed later than the tumors detected at screening. Studying interval cancers provides significant training for the radiologists in the PDPCM. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

Human sinus arrhythmia as an index of vagal cardiac outflow

NASA Technical Reports Server (NTRS)

Eckberg, D. L.

1983-01-01

The human central vagal mechanisms were investigated by measuring the intervals between heartbeats during controlled breathing (at breathing intervals of 2.5-10 s and nominal tidal volumes of 1000 and 1500 ml) in six young men and women. It was found that as the breathing interval increased, the longest heart periods became longer, the shortest heart periods became shorter, and the peak-valley P-P intervals increased asymptotically. Peak-valley intervals also increased in proportion to tidal volume, although this influence was small. The phase angles between heart period changes and respiration were found to vary as linear functions of breathing interval. Heart period shortening began in inspiration at short breathing intervals and in expiration at long breathing intervals, while heart period lengthening began in early expiration at all breathing intervals studied. It is concluded that a close relationship exists between variations of respiratory depth and interval and the quantity, periodicity, and timing of vagal cardiac outflow in conscious humans. The results indicate that at usual breathing rates, phasic respiration-related changes of vagal motoneuron activity begin in expiration, progress slowly, and are incompletely expressed at fast breathing ratges.

Quantitative survival impact of composite treatment delays in head and neck cancer.

PubMed

Ho, Allen S; Kim, Sungjin; Tighiouart, Mourad; Mita, Alain; Scher, Kevin S; Epstein, Joel B; Laury, Anna; Prasad, Ravi; Ali, Nabilah; Patio, Chrysanta; St-Clair, Jon Mallen; Zumsteg, Zachary S

2018-05-09

Multidisciplinary management of head and neck cancer (HNC) must reconcile increasingly sophisticated subspecialty care with timeliness of care. Prior studies examined the individual effects of delays in diagnosis-to-treatment interval, postoperative interval, and radiation interval but did not consider them collectively. The objective of the current study was to investigate the combined impact of these interwoven intervals on patients with HNC. Patients with HNC who underwent curative-intent surgery with radiation were identified in the National Cancer Database between 2004 and 2013. Multivariable models were constructed using restricted cubic splines to determine nonlinear relations with overall survival. Overall, 15,064 patients were evaluated. After adjustment for covariates, only prolonged postoperative interval (P < .001) and radiation interval (P < .001) independently predicted for worse outcomes, whereas the association of diagnosis-to-treatment interval with survival disappeared. By using multivariable restricted cubic spline functions, increasing postoperative interval did not affect mortality until 40 days after surgery, and each day of delay beyond this increased the risk of mortality until 70 days after surgery (hazard ratio, 1.14; 95% confidence interval, 1.01-1.28; P = .029). For radiation interval, mortality escalated continuously with each additional day of delay, plateauing at 55 days (hazard ratio, 1.25; 95% confidence interval, 1.11-1.41; P < .001). Delays beyond these change points were not associated with further survival decrements. Increasing delays in postoperative and radiation intervals are associated independently with an escalating risk of mortality that plateaus beyond certain thresholds. Delays in initiating therapy, conversely, are eclipsed in importance when appraised in conjunction with the entire treatment course. Such findings may redirect focus to streamlining those intervals that are most sensitive to delays when considering survival burden. Cancer 2018. © 2018 American Cancer Society. © 2018 American Cancer Society.

Empirical likelihood-based confidence intervals for mean medical cost with censored data.

PubMed

Jeyarajah, Jenny; Qin, Gengsheng

2017-11-10

In this paper, we propose empirical likelihood methods based on influence function and jackknife techniques for constructing confidence intervals for mean medical cost with censored data. We conduct a simulation study to compare the coverage probabilities and interval lengths of our proposed confidence intervals with that of the existing normal approximation-based confidence intervals and bootstrap confidence intervals. The proposed methods have better finite-sample performances than existing methods. Finally, we illustrate our proposed methods with a relevant example. Copyright © 2017 John Wiley & Sons, Ltd.

[Estimation of the atrioventricular time interval by pulse Doppler in the normal fetal heart].

PubMed

Hamela-Olkowska, Anita; Dangel, Joanna

2009-08-01

To assess normative values of the fetal atrioventricular (AV) time interval by pulse-wave Doppler methods on 5-chamber view. Fetal echocardiography exams were performed using Acuson Sequoia 512 in 140 singleton fetuses at 18 to 40 weeks of gestation with sinus rhythm and normal cardiac and extracardiac anatomy. Pulsed Doppler derived AV intervals were measured from left ventricular inflow/outflow view using transabdominal convex 3.5-6 MHz probe. The values of AV time interval ranged from 100 to 150 ms (mean 123 +/- 11.2). The AV interval was negatively correlated with the heart rhythm (p<0.001). Fetal heart rate decreased as gestation progressed (p<0.001). Thus, the AV intervals increased with the age of gestation (p=0.007). However, in the same subgroup of the fetal heart rate there was no relation between AV intervals and gestational age. Therefore, the AV intervals showed only the heart rate dependence. The 95th percentiles of AV intervals according to FHR ranged from 135 to 148 ms. 1. The AV interval duration was negatively correlated with the heart rhythm. 2. Measurement of AV time interval is easy to perform and has a good reproducibility. It may be used for the fetal heart block screening in anti-Ro and anti-La positive pregnancies. 3. Normative values established in the study may help obstetricians in assessing fetal abnormalities of the AV conduction.

Interval Training

MedlinePlus

Healthy Lifestyle Fitness Interval training can help you get the most out of your workout. By Mayo Clinic Staff Are you ready to shake ... spending more time at the gym? Consider aerobic interval training. Once the domain of elite athletes, interval training ...

A new technique to determine the correlation between the QT interval and heart-rate for control and SIDS babies

NASA Technical Reports Server (NTRS)

Sadeh, D.; Shannon, D. C.; Abboud, S.; Akselrod, S.; Cohen, R. J.

1987-01-01

The ability of the autonomic nervous system to alter the QT interval in response to heart rate changes is essential to cardiovascular control. An accurate way to determine the relation between QT intervals and their corresponding RR intervals is described. A computer algorithm measures the RR intervals using digital filtering and cross-correlating the QRS sections of consecutive waveforms. The QT intervals is calculated by choosing a section of, the ECG that includes the T wave and cross-correlating it with all the consecutive T waves. At least 4000 pairs of QT-RR intervals are computed for each subject and a best fit correlation function determines the relations between the QT and RR intervals. This technique enables to establish a precise correlation between RR and QT in order to distinguish between control and SIDS babies.

Volatility return intervals analysis of the Japanese market

NASA Astrophysics Data System (ADS)

Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

2008-03-01

We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean <τ>. We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

Increasing accuracy in the interval analysis by the improved format of interval extension based on the first order Taylor series

NASA Astrophysics Data System (ADS)

Li, Yi; Xu, Yan Long

2018-05-01

When the dependence of the function on uncertain variables is non-monotonic in interval, the interval of function obtained by the classic interval extension based on the first order Taylor series will exhibit significant errors. In order to reduce theses errors, the improved format of the interval extension with the first order Taylor series is developed here considering the monotonicity of function. Two typical mathematic examples are given to illustrate this methodology. The vibration of a beam with lumped masses is studied to demonstrate the usefulness of this method in the practical application, and the necessary input data of which are only the function value at the central point of interval, sensitivity and deviation of function. The results of above examples show that the interval of function from the method developed by this paper is more accurate than the ones obtained by the classic method.

ELECTRICAL LOAD ANTICIPATOR AND RECORDER

DOEpatents

Werme, J.E.

1961-09-01

A system is described in which an indication of the prevailing energy consumption in an electrical power metering system and a projected power demand for one demand in terval is provided at selected increments of time within the demand interval. Each watt-hour meter in the system is provided with an impulse generator that generates two impulses for each revolution of the meter disc. In each demand interval, for example, one half-hour, of the metering system, the total impulses received from all of the meters are continuously totaled for each 5-minute interval and multiplied by a number from 6 to 1 depending upon which 5- minute interval the impulses were received. This value is added to the total pulses received in the intervals preceding the current 5-minute interval within the half-hour demand interval tc thereby provide an indication of the projected power demand every 5 minutes in the demand interval.

High resolution data acquisition

DOEpatents

Thornton, G.W.; Fuller, K.R.

1993-04-06

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock, pulse train, and analog circuitry for generating a triangular wave synchronously with the pulse train (as seen in diagram on patent). The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

High resolution data acquisition

DOEpatents

Thornton, Glenn W.; Fuller, Kenneth R.

1993-01-01

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

The influence of interpregnancy interval on infant mortality.

PubMed

McKinney, David; House, Melissa; Chen, Aimin; Muglia, Louis; DeFranco, Emily

2017-03-01

In Ohio, the infant mortality rate is above the national average and the black infant mortality rate is more than twice the white infant mortality rate. Having a short interpregnancy interval has been shown to correlate with preterm birth and low birthweight, but the effect of short interpregnancy interval on infant mortality is less well established. We sought to quantify the population impact of interpregnancy interval on the risk of infant mortality. This was a statewide population-based retrospective cohort study of all births (n = 1,131,070) and infant mortalities (n = 8152) using linked Ohio birth and infant death records from January 2007 through September 2014. For this study we analyzed 5 interpregnancy interval categories: 0-<6, 6-<12, 12-<24, 24-<60, and ≥60 months. The primary outcome for this study was infant mortality. During the study period, 3701 infant mortalities were linked to a live birth certificate with an interpregnancy interval available. We calculated the frequency and relative risk of infant mortality for each interval compared to a referent interval of 12-<24 months. Stratified analyses by maternal race were also performed. Adjusted risks were estimated after accounting for statistically significant and biologically plausible confounding variables. Adjusted relative risk was utilized to calculate the attributable risk percent of short interpregnancy intervals on infant mortality. Short interpregnancy intervals were common in Ohio during the study period. Of all multiparous births, 20.5% followed an interval of <12 months. The overall infant mortality rate during this time was 7.2 per 1000 live births (6.0 for white mothers and 13.1 for black mothers). Infant mortalities occurred more frequently for births following short intervals of 0-<6 months (9.2 per 1000) and 6-<12 months (7.1 per 1000) compared to 12-<24 months (5.6 per 1000) (P < .001 and <.001). The highest risk for infant mortality followed interpregnancy intervals of 0-<6 months (adjusted relative risk, 1.32; 95% confidence interval, 1.17-1.49) followed by interpregnancy intervals of 6-<12 months (adjusted relative risk, 1.16; 95% confidence interval, 1.04-1.30). Analysis stratified by maternal race revealed similar findings. Attributable risk calculation showed that 24.2% of infant mortalities following intervals of 0-<6 months and 14.1% with intervals of 6-<12 months are attributable to the short interpregnancy interval. By avoiding short interpregnancy intervals of ≤12 months we estimate that in the state of Ohio 31 infant mortalities (20 white and 8 black) per year could have been prevented and the infant mortality rate could have been reduced from 7.2-7.0 during this time frame. An interpregnancy interval of 12-60 months (1-5 years) between birth and conception of next pregnancy is associated with lowest risk of infant mortality. Public health initiatives and provider counseling to optimize birth spacing has the potential to significantly reduce infant mortality for both white and black mothers. Copyright © 2017 Elsevier Inc. All rights reserved.

Short-Term Depression, Temporal Summation, and Onset Inhibition Shape Interval Tuning in Midbrain Neurons

PubMed Central

Baker, Christa A.

2014-01-01

A variety of synaptic mechanisms can contribute to single-neuron selectivity for temporal intervals in sensory stimuli. However, it remains unknown how these mechanisms interact to establish single-neuron sensitivity to temporal patterns of sensory stimulation in vivo. Here we address this question in a circuit that allows us to control the precise temporal patterns of synaptic input to interval-tuned neurons in behaviorally relevant ways. We obtained in vivo intracellular recordings under multiple levels of current clamp from midbrain neurons in the mormyrid weakly electric fish Brienomyrus brachyistius during stimulation with electrosensory pulse trains. To reveal the excitatory and inhibitory inputs onto interval-tuned neurons, we then estimated the synaptic conductances underlying responses. We found short-term depression in excitatory and inhibitory pathways onto all interval-tuned neurons. Short-interval selectivity was associated with excitation that depressed less than inhibition at short intervals, as well as temporally summating excitation. Long-interval selectivity was associated with long-lasting onset inhibition. We investigated tuning after separately nullifying the contributions of temporal summation and depression, and found the greatest diversity of interval selectivity among neurons when both mechanisms were at play. Furthermore, eliminating the effects of depression decreased sensitivity to directional changes in interval. These findings demonstrate that variation in depression and summation of excitation and inhibition helps to establish tuning to behaviorally relevant intervals in communication signals, and that depression contributes to neural coding of interval sequences. This work reveals for the first time how the interplay between short-term plasticity and temporal summation mediates the decoding of temporal sequences in awake, behaving animals. PMID:25339741

Factors influencing pre-hospital care time intervals in Iran: a qualitative study.

PubMed

Khorasani-Zavareh, Davoud; Mohammadi, Reza; Bohm, Katarina

2018-06-23

Pre-hospital time management provides better access to victims of road traffic crashes (RTCs) and can help minimize preventable deaths, injuries and disabilities. While most studies have been focused on measuring various time intervals in the pre-hospital phase, to our best knowledge there is no study exploring the barriers and facilitators that affects these various intervals qualitatively. The present study aimed to explore factors affecting various time intervals relating to road traffic incidents in the pre-hospital phase and provides suggestions for improvements in Iran. The study was conducted during 2013-2014 at both the national and local level in Iran. Overall, 18 face-to-face interviews with emergency medical services (EMS) personnel were used for data collection. Qualitative content analysis was employed to analyze the data. The most important barriers in relation to pre-hospital intervals were related to the manner of cooperation by members of the public with the EMS and their involvement at the crash scene, as well as to pre-hospital system factors, including the number and location of EMS facilities, type and number of ambulances and manpower. These factors usually affect how rapidly the EMS can arrive at the scene of the crash and how quickly victims can be transferred to hospital. These two categories have six main themes: notification interval; activation interval; response interval; on-scene interval; transport interval; and delivery interval. Despite more focus on physical resources, cooperation from members of the public needs to be taken in account in order to achieve better pre-hospital management of the various intervals, possibly through the use of public education campaigns.

Prolonged corrected QT interval is predictive of future stroke events even in subjects without ECG-diagnosed left ventricular hypertrophy.

PubMed

Ishikawa, Joji; Ishikawa, Shizukiyo; Kario, Kazuomi

2015-03-01

We attempted to evaluate whether subjects who exhibit prolonged corrected QT (QTc) interval (≥440 ms in men and ≥460 ms in women) on ECG, with and without ECG-diagnosed left ventricular hypertrophy (ECG-LVH; Cornell product, ≥244 mV×ms), are at increased risk of stroke. Among the 10 643 subjects, there were a total of 375 stroke events during the follow-up period (128.7±28.1 months; 114 142 person-years). The subjects with prolonged QTc interval (hazard ratio, 2.13; 95% confidence interval, 1.22-3.73) had an increased risk of stroke even after adjustment for ECG-LVH (hazard ratio, 1.71; 95% confidence interval, 1.22-2.40). When we stratified the subjects into those with neither a prolonged QTc interval nor ECG-LVH, those with a prolonged QTc interval but without ECG-LVH, and those with ECG-LVH, multivariate-adjusted Cox proportional hazards analysis demonstrated that the subjects with prolonged QTc intervals but not ECG-LVH (1.2% of all subjects; incidence, 10.7%; hazard ratio, 2.70, 95% confidence interval, 1.48-4.94) and those with ECG-LVH (incidence, 7.9%; hazard ratio, 1.83; 95% confidence interval, 1.31-2.57) had an increased risk of stroke events, compared with those with neither a prolonged QTc interval nor ECG-LVH. In conclusion, prolonged QTc interval was associated with stroke risk even among patients without ECG-LVH in the general population. © 2014 American Heart Association, Inc.

Binary Interval Search: a scalable algorithm for counting interval intersections

PubMed Central

Layer, Ryan M.; Skadron, Kevin; Robins, Gabriel; Hall, Ira M.; Quinlan, Aaron R.

2013-01-01

Motivation: The comparison of diverse genomic datasets is fundamental to understand genome biology. Researchers must explore many large datasets of genome intervals (e.g. genes, sequence alignments) to place their experimental results in a broader context and to make new discoveries. Relationships between genomic datasets are typically measured by identifying intervals that intersect, that is, they overlap and thus share a common genome interval. Given the continued advances in DNA sequencing technologies, efficient methods for measuring statistically significant relationships between many sets of genomic features are crucial for future discovery. Results: We introduce the Binary Interval Search (BITS) algorithm, a novel and scalable approach to interval set intersection. We demonstrate that BITS outperforms existing methods at counting interval intersections. Moreover, we show that BITS is intrinsically suited to parallel computing architectures, such as graphics processing units by illustrating its utility for efficient Monte Carlo simulations measuring the significance of relationships between sets of genomic intervals. Availability: https://github.com/arq5x/bits. Contact: arq5x@virginia.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23129298

An approach to solve group-decision-making problems with ordinal interval numbers.

PubMed

Fan, Zhi-Ping; Liu, Yang

2010-10-01

The ordinal interval number is a form of uncertain preference information in group decision making (GDM), while it is seldom discussed in the existing research. This paper investigates how the ranking order of alternatives is determined based on preference information of ordinal interval numbers in GDM problems. When ranking a large quantity of ordinal interval numbers, the efficiency and accuracy of the ranking process are critical. A new approach is proposed to rank alternatives using ordinal interval numbers when every ranking ordinal in an ordinal interval number is thought to be uniformly and independently distributed in its interval. First, we give the definition of possibility degree on comparing two ordinal interval numbers and the related theory analysis. Then, to rank alternatives, by comparing multiple ordinal interval numbers, a collective expectation possibility degree matrix on pairwise comparisons of alternatives is built, and an optimization model based on this matrix is constructed. Furthermore, an algorithm is also presented to rank alternatives by solving the model. Finally, two examples are used to illustrate the use of the proposed approach.

Evaluation of confidence intervals for a steady-state leaky aquifer model

USGS Publications Warehouse

Christensen, S.; Cooley, R.L.

1999-01-01

The fact that dependent variables of groundwater models are generally nonlinear functions of model parameters is shown to be a potentially significant factor in calculating accurate confidence intervals for both model parameters and functions of the parameters, such as the values of dependent variables calculated by the model. The Lagrangian method of Vecchia and Cooley [Vecchia, A.V. and Cooley, R.L., Water Resources Research, 1987, 23(7), 1237-1250] was used to calculate nonlinear Scheffe-type confidence intervals for the parameters and the simulated heads of a steady-state groundwater flow model covering 450 km2 of a leaky aquifer. The nonlinear confidence intervals are compared to corresponding linear intervals. As suggested by the significant nonlinearity of the regression model, linear confidence intervals are often not accurate. The commonly made assumption that widths of linear confidence intervals always underestimate the actual (nonlinear) widths was not correct. Results show that nonlinear effects can cause the nonlinear intervals to be asymmetric and either larger or smaller than the linear approximations. Prior information on transmissivities helps reduce the size of the confidence intervals, with the most notable effects occurring for the parameters on which there is prior information and for head values in parameter zones for which there is prior information on the parameters.The fact that dependent variables of groundwater models are generally nonlinear functions of model parameters is shown to be a potentially significant factor in calculating accurate confidence intervals for both model parameters and functions of the parameters, such as the values of dependent variables calculated by the model. The Lagrangian method of Vecchia and Cooley was used to calculate nonlinear Scheffe-type confidence intervals for the parameters and the simulated heads of a steady-state groundwater flow model covering 450 km2 of a leaky aquifer. The nonlinear confidence intervals are compared to corresponding linear intervals. As suggested by the significant nonlinearity of the regression model, linear confidence intervals are often not accurate. The commonly made assumption that widths of linear confidence intervals always underestimate the actual (nonlinear) widths was not correct. Results show that nonlinear effects can cause the nonlinear intervals to be asymmetric and either larger or smaller than the linear approximations. Prior information on transmissivities helps reduce the size of the confidence intervals, with the most notable effects occurring for the parameters on which there is prior information and for head values in parameter zones for which there is prior information on the parameters.

A Microsoft Excel® 2010 Based Tool for Calculating Interobserver Agreement

PubMed Central

Azulay, Richard L

2011-01-01

This technical report provides detailed information on the rationale for using a common computer spreadsheet program (Microsoft Excel®) to calculate various forms of interobserver agreement for both continuous and discontinuous data sets. In addition, we provide a brief tutorial on how to use an Excel spreadsheet to automatically compute traditional total count, partial agreement-within-intervals, exact agreement, trial-by-trial, interval-by-interval, scored-interval, unscored-interval, total duration, and mean duration-per-interval interobserver agreement algorithms. We conclude with a discussion of how practitioners may integrate this tool into their clinical work. PMID:22649578

A microsoft excel(®) 2010 based tool for calculating interobserver agreement.

PubMed

Reed, Derek D; Azulay, Richard L

2011-01-01

This technical report provides detailed information on the rationale for using a common computer spreadsheet program (Microsoft Excel(®)) to calculate various forms of interobserver agreement for both continuous and discontinuous data sets. In addition, we provide a brief tutorial on how to use an Excel spreadsheet to automatically compute traditional total count, partial agreement-within-intervals, exact agreement, trial-by-trial, interval-by-interval, scored-interval, unscored-interval, total duration, and mean duration-per-interval interobserver agreement algorithms. We conclude with a discussion of how practitioners may integrate this tool into their clinical work.

Limited Rationality and Its Quantification Through the Interval Number Judgments With Permutations.

PubMed

Liu, Fang; Pedrycz, Witold; Zhang, Wei-Guo

2017-12-01

The relative importance of alternatives expressed in terms of interval numbers in the fuzzy analytic hierarchy process aims to capture the uncertainty experienced by decision makers (DMs) when making a series of comparisons. Under the assumption of full rationality, the judgements of DMs in the typical analytic hierarchy process could be consistent. However, since the uncertainty in articulating the opinions of DMs is unavoidable, the interval number judgements are associated with the limited rationality. In this paper, we investigate the concept of limited rationality by introducing interval multiplicative reciprocal comparison matrices. By analyzing the consistency of interval multiplicative reciprocal comparison matrices, it is observed that the interval number judgements are inconsistent. By considering the permutations of alternatives, the concepts of approximation-consistency and acceptable approximation-consistency of interval multiplicative reciprocal comparison matrices are proposed. The exchange method is designed to generate all the permutations. A novel method of determining the interval weight vector is proposed under the consideration of randomness in comparing alternatives, and a vector of interval weights is determined. A new algorithm of solving decision making problems with interval multiplicative reciprocal preference relations is provided. Two numerical examples are carried out to illustrate the proposed approach and offer a comparison with the methods available in the literature.

The dose delivery effect of the different Beam ON interval in FFF SBRT: TrueBEAM

NASA Astrophysics Data System (ADS)

Tawonwong, T.; Suriyapee, S.; Oonsiri, S.; Sanghangthum, T.; Oonsiri, P.

2016-03-01

The purpose of this study is to determine the dose delivery effect of the different Beam ON interval in Flattening Filter Free Stereotactic Body Radiation Therapy (FFF-SBRT). The three 10MV-FFF SBRT plans (2 half rotating Rapid Arc, 9 to10 Gray/Fraction) were selected and irradiated in three different intervals (100%, 50% and 25%) using the RPM gating system. The plan verification was performed by the ArcCHECK for gamma analysis and the ionization chamber for point dose measurement. The dose delivery time of each interval were observed. For gamma analysis (2%&2mm criteria), the average percent pass of all plans for 100%, 50% and 25% intervals were 86.1±3.3%, 86.0±3.0% and 86.1±3.3%, respectively. For point dose measurement, the average ratios of each interval to the treatment planning were 1.012±0.015, 1.011±0.014 and 1.011±0.013 for 100%, 50% and 25% interval, respectively. The average dose delivery time was increasing from 74.3±5.0 second for 100% interval to 154.3±12.6 and 347.9±20.3 second for 50% and 25% interval, respectively. The same quality of the dose delivery from different Beam ON intervals in FFF-SBRT by TrueBEAM was illustrated. While the 100% interval represents the breath-hold treatment technique, the differences for the free-breathing using RPM gating system can be treated confidently.

[Association between oxytocin augmentation intervals and the risk of postpartum haemorrhage].

PubMed

Loscul, C; Chantry, A-A; Caubit, L; Deneux-Tharaux, C; Goffinet, F; Le Ray, C

2016-09-01

To study the association between the duration of oxytocin augmentation intervals and the risk of postpartum haemorrhage (PPH) among primiparous women in spontaneous labour. Retrospective cohort including primiparous women in spontaneous labour who received oxytocin during labour (n=454). Oxytocin augmentation intervals were dichotomized in intervals<20minutes and≥20minutes. Obstetrical and neonatal issues were analyzed according to the duration oxytocin augmentation intervals. The association between oxytocin augmentation intervals and PPH was analyzed using univariate and multivariate analysis. Oxytocin augmentation intervals were shorter than 20minutes for 43.8% of the study population. The rate of PPH was higher (9.1% vs 3.5%; P=0.014), and the use of sulprostone was more frequent (6.5% vs 3.5%; P=0.013) if oxytocin augmentation intervals were shorter than 20minutes in comparison with intervals≥20minutes. The association between oxytocin augmentation intervals and PPH remains significant after adjustment on other PPH risk factors (adjusted OR=3.48, 95% CI [1.45-8.34]). The rate of adverse neonatal issue, defined by arterial pH at birth≤7.10 and/or 5minutes score d'Apgar≤7, was higher if oxytocin augmentation intervals were<20minutes (12.1% vs 4.3%; P=0.002). Our study demonstrated an increased risk of PPH for primiparous women in spontaneous labour who received oxytocin with augmentation intervals shorter than 20minutes. Copyright © 2016. Published by Elsevier Masson SAS.

Statistical analysis on multifractal detrended cross-correlation coefficient for return interval by oriented percolation

NASA Astrophysics Data System (ADS)

Deng, Wei; Wang, Jun

2015-06-01

We investigate and quantify the multifractal detrended cross-correlation of return interval series for Chinese stock markets and a proposed price model, the price model is established by oriented percolation. The return interval describes the waiting time between two successive price volatilities which are above some threshold, the present work is an attempt to quantify the level of multifractal detrended cross-correlation for the return intervals. Further, the concept of MF-DCCA coefficient of return intervals is introduced, and the corresponding empirical research is performed. The empirical results show that the return intervals of SSE and SZSE are weakly positive multifractal power-law cross-correlated, and exhibit the fluctuation patterns of MF-DCCA coefficients. The similar behaviors of return intervals for the price model is also demonstrated.

Minimax confidence intervals in geomagnetism

NASA Technical Reports Server (NTRS)

Stark, Philip B.

1992-01-01

The present paper uses theory of Donoho (1989) to find lower bounds on the lengths of optimally short fixed-length confidence intervals (minimax confidence intervals) for Gauss coefficients of the field of degree 1-12 using the heat flow constraint. The bounds on optimal minimax intervals are about 40 percent shorter than Backus' intervals: no procedure for producing fixed-length confidence intervals, linear or nonlinear, can give intervals shorter than about 60 percent the length of Backus' in this problem. While both methods rigorously account for the fact that core field models are infinite-dimensional, the application of the techniques to the geomagnetic problem involves approximations and counterfactual assumptions about the data errors, and so these results are likely to be extremely optimistic estimates of the actual uncertainty in Gauss coefficients.

IBM system/360 assembly language interval arithmetic software

NASA Technical Reports Server (NTRS)

Phillips, E. J.

1972-01-01

Computer software designed to perform interval arithmetic is described. An interval is defined as the set of all real numbers between two given numbers including or excluding one or both endpoints. Interval arithmetic consists of the various elementary arithmetic operations defined on the set of all intervals, such as interval addition, subtraction, union, etc. One of the main applications of interval arithmetic is in the area of error analysis of computer calculations. For example, it has been used sucessfully to compute bounds on sounding errors in the solution of linear algebraic systems, error bounds in numerical solutions of ordinary differential equations, as well as integral equations and boundary value problems. The described software enables users to implement algorithms of the type described in references efficiently on the IBM 360 system.

Reversing the Course of Forgetting

PubMed Central

White, K. Geoffrey; Brown, Glenn S

2011-01-01

Forgetting functions were generated for pigeons in a delayed matching-to-sample task, in which accuracy decreased with increasing retention-interval duration. In baseline training with dark retention intervals, accuracy was high overall. Illumination of the experimental chamber by a houselight during the retention interval impaired performance accuracy by increasing the rate of forgetting. In novel conditions, the houselight was lit at the beginning of a retention interval and then turned off partway through the retention interval. Accuracy was low at the beginning of the retention interval and then increased later in the interval. Thus the course of forgetting was reversed. Such a dissociation of forgetting from the passage of time is consistent with an interference account in which attention or stimulus control switches between the remembering task and extraneous events. PMID:21909163

Comparing interval estimates for small sample ordinal CFA models

PubMed Central

Natesan, Prathiba

2015-01-01

Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research. PMID:26579002

QT-RR relationships and suitable QT correction formulas for halothane-anesthetized dogs.

PubMed

Tabo, Mitsuyasu; Nakamura, Mikiko; Kimura, Kazuya; Ito, Shigeo

2006-10-01

Several QT correction (QTc) formulas have been used for assessing the QT liability of drugs. However, they are known to under- and over-correct the QT interval and tend to be specific to species and experimental conditions. The purpose of this study was to determine a suitable formula for halothane-anesthetized dogs highly sensitive to drug-induced QT interval prolongation. Twenty dogs were anesthetized with 1.5% halothane and the relationship between the QT and RR intervals were obtained by changing the heart rate under atrial pacing conditions. The QT interval was corrected for the RR interval by applying 4 published formulas (Bazett, Fridericia, Van de Water, and Matsunaga); Fridericia's formula (QTcF = QT/RR(0.33)) showed the least slope and lowest R(2) value for the linear regression of QTc intervals against RR intervals, indicating that it dissociated changes in heart rate most effectively. An optimized formula (QTcX = QT/RR(0.3879)) is defined by analysis of covariance and represents a correction algorithm superior to Fridericia's formula. For both Fridericia's and the optimized formula, QT-prolonging drugs (d,l-sotalol, astemizole) showed QTc interval prolongation. A non-QT-prolonging drug (d,l-propranolol) failed to prolong the QTc interval. In addition, drug-induced changes in QTcF and QTcX intervals were highly correlated with those of the QT interval paced at a cycle length of 500 msec. These findings suggest that Fridericia's and the optimized formula, although the optimized is a little bit better, are suitable for correcting the QT interval in halothane-anesthetized dogs and help to evaluate the potential QT prolongation of drugs with high accuracy.

CLSI-based transference of CALIPER pediatric reference intervals to Beckman Coulter AU biochemical assays.

PubMed

Abou El Hassan, Mohamed; Stoianov, Alexandra; Araújo, Petra A T; Sadeghieh, Tara; Chan, Man Khun; Chen, Yunqi; Randell, Edward; Nieuwesteeg, Michelle; Adeli, Khosrow

2015-11-01

The CALIPER program has established a comprehensive database of pediatric reference intervals using largely the Abbott ARCHITECT biochemical assays. To expand clinical application of CALIPER reference standards, the present study is aimed at transferring CALIPER reference intervals from the Abbott ARCHITECT to Beckman Coulter AU assays. Transference of CALIPER reference intervals was performed based on the CLSI guidelines C28-A3 and EP9-A2. The new reference intervals were directly verified using up to 100 reference samples from the healthy CALIPER cohort. We found a strong correlation between Abbott ARCHITECT and Beckman Coulter AU biochemical assays, allowing the transference of the vast majority (94%; 30 out of 32 assays) of CALIPER reference intervals previously established using Abbott assays. Transferred reference intervals were, in general, similar to previously published CALIPER reference intervals, with some exceptions. Most of the transferred reference intervals were sex-specific and were verified using healthy reference samples from the CALIPER biobank based on CLSI criteria. It is important to note that the comparisons performed between the Abbott and Beckman Coulter assays make no assumptions as to assay accuracy or which system is more correct/accurate. The majority of CALIPER reference intervals were transferrable to Beckman Coulter AU assays, allowing the establishment of a new database of pediatric reference intervals. This further expands the utility of the CALIPER database to clinical laboratories using the AU assays; however, each laboratory should validate these intervals for their analytical platform and local population as recommended by the CLSI. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Measuring the EMS patient access time interval and the impact of responding to high-rise buildings.

PubMed

Morrison, Laurie J; Angelini, Mark P; Vermeulen, Marian J; Schwartz, Brian

2005-01-01

To measure the patient access time interval and characterize its contribution to the total emergency medical services (EMS) response time interval; to compare the patient access time intervals for patients located three or more floors above ground with those less than three floors above or below ground, and specifically in the apartment subgroup; and to identify barriers that significantly impede EMS access to patients in high-rise apartments. An observational study of all patients treated by an emergency medical technician paramedics (EMT-P) crew was conducted using a trained independent observer to collect time intervals and identify potential barriers to access. Of 118 observed calls, 25 (21%) originated from patients three or more floors above ground. The overall median and 90th percentile (95% confidence interval) patient access time intervals were 1.61 (1.27, 1.91) and 3.47 (3.08, 4.05) minutes, respectively. The median interval was 2.73 (2.22, 3.03) minutes among calls from patients located three or more stories above ground compared with 1.25 (1.07, 1.55) minutes among those at lower levels. The patient access time interval represented 23.5% of the total EMS response time interval among calls originating less than three floors above or below ground and 32.2% of those located three or more stories above ground. The most frequently encountered barriers to access included security code entry requirements, lack of directional signs, and inability to fit the stretcher into the elevator. The patient access time interval is significantly long and represents a substantial component of the total EMS response time interval, especially among ambulance calls originating three or more floors above ground. A number of barriers appear to contribute to delayed paramedic access.

Patient satisfaction with extended-interval warfarin monitoring.

PubMed

Carris, Nicholas W; Hwang, Andrew Y; Smith, Steven M; Taylor, James R; Sando, Karen; Powell, Jason; Rosenberg, Eric I; Zumberg, Marc S; Gums, John G; Dietrich, Eric A; Anderson, Katherine Vogel

2016-11-01

Extended-interval monitoring of warfarin has been proposed to reduce follow-up burden and improve patient satisfaction. We aimed to make an initial assessment of anticoagulation satisfaction before and after an extended-interval warfarin monitoring intervention. We conducted a translational prospective single-arm pilot study of extended-interval warfarin monitoring in five pharmacist-managed anticoagulation clinics. Patients meeting CHEST guideline criteria for extended-interval warfarin monitoring began progressive extended-interval follow-up (6, 8, and 12 weeks thereafter). The Duke Anticoagulation Satisfaction Scale (DASS) was administered at baseline and at end-of-study or study removal (in patients no longer appropriate for extended interval follow-up). Forty-six patients had evaluable pre- and post-intervention DASS survey data. Mean age of patients was 66.5 years, 74 % were non-Hispanic whites, and 48 % were men. Patients completed a mean ± SD of 34 ± 22 weeks of follow-up. Mean ± SD total DASS score at baseline was 45.2 ± 14.2 versus 49.1 ± 14.9 at end-of-study (mean change, +3.9 [95 % CI -0.6-8.4; p = 0.09]), indicating no benefit-and trending toward decrement-to anticoagulation satisfaction. Change in anticoagulation satisfaction varied substantially following extended-interval monitoring, with no evidence of improved satisfaction. Plausible reasons for patients not preferring extended-interval monitoring include increased anxiety and disengagement from self-management activities, both potentially related to less frequent feedback and reassurance during extended interval-monitoring. Additional research is needed to identify who is likely to benefit most from extended-interval monitoring. Anticoagulation satisfaction should be considered with clinical factors and shared-decision making when implementing extended-interval warfarin monitoring.

Musical training generalises across modalities and reveals efficient and adaptive mechanisms for reproducing temporal intervals.

PubMed

Aagten-Murphy, David; Cappagli, Giulia; Burr, David

2014-03-01

Expert musicians are able to time their actions accurately and consistently during a musical performance. We investigated how musical expertise influences the ability to reproduce auditory intervals and how this generalises across different techniques and sensory modalities. We first compared various reproduction strategies and interval length, to examine the effects in general and to optimise experimental conditions for testing the effect of music, and found that the effects were robust and consistent across different paradigms. Focussing on a 'ready-set-go' paradigm subjects reproduced time intervals drawn from distributions varying in total length (176, 352 or 704 ms) or in the number of discrete intervals within the total length (3, 5, 11 or 21 discrete intervals). Overall, Musicians performed more veridical than Non-Musicians, and all subjects reproduced auditory-defined intervals more accurately than visually-defined intervals. However, Non-Musicians, particularly with visual stimuli, consistently exhibited a substantial and systematic regression towards the mean interval. When subjects judged intervals from distributions of longer total length they tended to regress more towards the mean, while the ability to discriminate between discrete intervals within the distribution had little influence on subject error. These results are consistent with a Bayesian model that minimizes reproduction errors by incorporating a central tendency prior weighted by the subject's own temporal precision relative to the current distribution of intervals. Finally a strong correlation was observed between all durations of formal musical training and total reproduction errors in both modalities (accounting for 30% of the variance). Taken together these results demonstrate that formal musical training improves temporal reproduction, and that this improvement transfers from audition to vision. They further demonstrate the flexibility of sensorimotor mechanisms in adapting to different task conditions to minimise temporal estimation errors. © 2013.

Comparing interval estimates for small sample ordinal CFA models.

PubMed

Natesan, Prathiba

2015-01-01

Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading. Therefore, editors and policymakers should continue to emphasize the inclusion of interval estimates in research.

Application of Normative Occipital Condyle-C1 Interval Measurements to Detect Atlanto-Occipital Injury in Children.

PubMed

Corcoran, B; Linscott, L L; Leach, J L; Vadivelu, S

2016-05-01

Prior studies have found that widening or asymmetry of the occipital condyle-C1 interval on CT is a sensitive and specific marker for atlanto-occipital dislocation. Previously reported abnormal occipital condyle-C1 interval values are not age-specific, possibly leading to false-positive findings in younger children, in whom this joint space is normally larger than that in adults. This study assesses the utility of applying age-specific normative occipital condyle-C1 interval ranges to documented cases of atlanto-occipital injury compared with previously reported abnormal cutoff values. Retrospective review of CT and MR imaging of 14 subjects with atlanto-occipital injury was performed, and occipital condyle-C1 interval measurements were made for each subject. Sensitivities and specificities of proposed occipital condyle-C1 interval cutoffs of 2 and 3 SDs above the mean and previously published occipital condyle-C1 interval cutoffs for atlanto-occipital injury were then calculated on the basis of occipital condyle-C1 interval measurements for each subject. An occipital condyle-C1 interval 2 SDs above the age-specific mean has a sensitivity of 50% and specificity of 89%-100%, depending on the age group. An occipital condyle-C1 interval 3 SDs above the age-specific mean has a sensitivity of 50% and a specificity of 95%-100%. A 4.0-mm occipital condyle-C1 interval has a sensitivity of 36% and a specificity of 100% in all age groups. A 2.5-mm occipital condyle-C1 interval has a sensitivity of 93% and a specificity of 18%-100%. Occipital condyle-C1 interval widening cutoffs used to establish atlanto-occipital injury lack both sensitivity and specificity in children and young teenagers. MR imaging is necessary to establish a diagnosis of atlanto-occipital injury in children and young teenagers when the appropriate mechanism of injury is present. © 2016 by American Journal of Neuroradiology.

Effect of long interval between hyperthermochemoradiation therapy and surgery for rectal cancer on apoptosis, proliferation and tumor response.

PubMed

Kato, Toshihide; Fujii, Takaaki; Ide, Munenori; Takada, Takahiro; Sutoh, Toshinaga; Morita, Hiroki; Yajima, Reina; Yamaguchi, Satoru; Tsutsumi, Soichi; Asao, Takayuki; Oyama, Tetsunari; Kuwano, Hiroyuki

2014-06-01

Neoadjuvant chemoradiotherapy is commonly used to improve the local control and resectability of locally advanced rectal cancer, with surgery performed after an interval of a number of weeks. We have been conducting a clinical trial of preoperative chemoradiotherapy in combination with regional hyperthermia (hyperthermo-chemoradiation therapy; HCRT) for locally advanced rectal cancer. In the current study we assessed the effect of a longer (>10 weeks) interval after neoadjuvant HCRT on pathological response, oncological outcome and especially on apoptosis, proliferation and p53 expression in patients with rectal cancer. Forty-eight patients with proven rectal adenocarcinoma who underwent HCRT followed by surgery were identified for inclusion in this study. Patients were divided into two groups according to the interval between HCRT and surgery, ≤ 10 weeks (short-interval group) and >10 weeks (long-interval group). Patients in the long-interval group had a significantly higher rate of pathological complete response (pCR) (43.5% vs. 16.0%) than patients of the short-interval group. Patients of the long-interval group had a significantly higher rate of down-staging of T-stage (78.3% vs. 36.0%) and relatively higher rate of that of N-stage (52.2% vs. 36.0%) than patients of the short-interval group. Furthermore, apoptosis in the long-interval group was relatively higher compared to that of the short-interval group, without a significant difference in the Ki-67 proliferative index and expression of p53 in the primary tumor. In conclusion, we demonstrated that a longer interval after HCRT (>10 weeks) seemed to result in a better chance of a pCR, a result confirmed by the trends in tumor response markers, including apoptosis, proliferation and p53 expression. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

46 CFR 176.675 - Extension of examination intervals.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Extension of examination intervals. 176.675 Section 176... 100 GROSS TONS) INSPECTION AND CERTIFICATION Hull and Tailshaft Examinations § 176.675 Extension of examination intervals. The intervals between drydock examinations and internal structural examinations...

Reducing the width of confidence intervals for the difference between two population means by inverting adaptive tests.

PubMed

O'Gorman, Thomas W

2018-05-01

In the last decade, it has been shown that an adaptive testing method could be used, along with the Robbins-Monro search procedure, to obtain confidence intervals that are often narrower than traditional confidence intervals. However, these confidence interval limits require a great deal of computation and some familiarity with stochastic search methods. We propose a method for estimating the limits of confidence intervals that uses only a few tests of significance. We compare these limits to those obtained by a lengthy Robbins-Monro stochastic search and find that the proposed method is nearly as accurate as the Robbins-Monro search. Adaptive confidence intervals that are produced by the proposed method are often narrower than traditional confidence intervals when the distributions are long-tailed, skewed, or bimodal. Moreover, the proposed method of estimating confidence interval limits is easy to understand, because it is based solely on the p-values from a few tests of significance.

Interval stability for complex systems

NASA Astrophysics Data System (ADS)

Klinshov, Vladimir V.; Kirillov, Sergey; Kurths, Jürgen; Nekorkin, Vladimir I.

2018-04-01

Stability of dynamical systems against strong perturbations is an important problem of nonlinear dynamics relevant to many applications in various areas. Here, we develop a novel concept of interval stability, referring to the behavior of the perturbed system during a finite time interval. Based on this concept, we suggest new measures of stability, namely interval basin stability (IBS) and interval stability threshold (IST). IBS characterizes the likelihood that the perturbed system returns to the stable regime (attractor) in a given time. IST provides the minimal magnitude of the perturbation capable to disrupt the stable regime for a given interval of time. The suggested measures provide important information about the system susceptibility to external perturbations which may be useful for practical applications. Moreover, from a theoretical viewpoint the interval stability measures are shown to bridge the gap between linear and asymptotic stability. We also suggest numerical algorithms for quantification of the interval stability characteristics and demonstrate their potential for several dynamical systems of various nature, such as power grids and neural networks.

Final screening round of the NELSON lung cancer screening trial: the effect of a 2.5-year screening interval.

PubMed

Yousaf-Khan, Uraujh; van der Aalst, Carlijn; de Jong, Pim A; Heuvelmans, Marjolein; Scholten, Ernst; Lammers, Jan-Willem; van Ooijen, Peter; Nackaerts, Kristiaan; Weenink, Carla; Groen, Harry; Vliegenthart, Rozemarijn; Ten Haaf, Kevin; Oudkerk, Matthijs; de Koning, Harry

2017-01-01

In the USA annual lung cancer screening is recommended. However, the optimal screening strategy (eg, screening interval, screening rounds) is unknown. This study provides results of the fourth screening round after a 2.5-year interval in the Dutch-Belgian Lung Cancer Screening trial (NELSON). Europe's largest, sufficiently powered randomised lung cancer screening trial was designed to determine whether low-dose CT screening reduces lung cancer mortality by ≥25% compared with no screening after 10 years of follow-up. The screening arm (n=7915) received screening at baseline, after 1 year, 2 years and 2.5 years. Performance of the NELSON screening strategy in the final fourth round was evaluated. Comparisons were made between lung cancers detected in the first three rounds, in the final round and during the 2.5-year interval. In round 4, 46 cancers were screen-detected and there were 28 interval cancers between the third and fourth screenings. Compared with the second round screening (1-year interval), in round 4 a higher proportion of stage IIIb/IV cancers (17.3% vs 6.8%, p=0.02) and higher proportions of squamous-cell, bronchoalveolar and small-cell carcinomas (p=0.001) were detected. Compared with a 2-year interval, the 2.5-year interval showed a higher non-significant stage distribution (stage IIIb/IV 17.3% vs 5.2%, p=0.10). Additionally, more interval cancers manifested in the 2.5-year interval than in the intervals of previous rounds (28 vs 5 and 28 vs 19). A 2.5-year interval reduced the effect of screening: the interval cancer rate was higher compared with the 1-year and 2-year intervals, and proportion of advanced disease stage in the final round was higher compared with the previous rounds. ISRCTN63545820. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Interval sentinel lymph nodes in melanoma: a digital pathology analysis of Ki67 expression and microvascular density.

PubMed

Marinaccio, Christian; Giudice, Giuseppe; Nacchiero, Eleonora; Robusto, Fabio; Opinto, Giuseppina; Lastilla, Gaetano; Maiorano, Eugenio; Ribatti, Domenico

2016-08-01

The presence of interval sentinel lymph nodes in melanoma is documented in several studies, but controversies still exist about the management of these lymph nodes. In this study, an immunohistochemical evaluation of tumor cell proliferation and neo-angiogenesis has been performed with the aim of establishing a correlation between these two parameters between positive and negative interval sentinel lymph nodes. This retrospective study reviewed data of 23 patients diagnosed with melanoma. Bioptic specimens of interval sentinel lymph node were retrieved, and immunohistochemical reactions on tissue sections were performed using Ki67 as a marker of proliferation and CD31 as a blood vessel marker for the study of angiogenesis. The entire stained tissue sections for each case were digitized using Aperio Scanscope Cs whole-slide scanning platform and stored as high-resolution images. Image analysis was carried out on three selected fields of equal area using IHC Nuclear and Microvessel analysis algorithms to determine positive Ki67 nuclei and vessel number. Patients were divided into positive and negative interval sentinel lymph node groups, and the positive interval sentinel lymph node group was further divided into interval positive with micrometastasis and interval positive with macrometastasis subgroups. The analysis revealed a significant difference between positive and negative interval sentinel lymph nodes in the percentage of Ki67-positive nuclei and mean vessel number suggestive of an increased cellular proliferation and angiogenesis in positive interval sentinel lymph nodes. Further analysis in the interval positive lymph node group showed a significant difference between micro- and macrometastasis subgroups in the percentage of Ki67-positive nuclei and mean vessel number. Percentage of Ki67-positive nuclei was increased in the macrometastasis subgroup, while mean vessel number was increased in the micrometastasis subgroup. The results of this study suggest that the correlation between tumor cell proliferation and neo-angiogenesis in interval sentinel lymph nodes in melanoma could be used as a good predictive marker to distinguish interval positive sentinel lymph nodes with micrometastasis from interval positive lymph nodes with macrometastasis subgroups.

Association of low-moderate urine arsenic and QT interval: Cross-sectional and longitudinal evidence from the Strong Heart Study.

PubMed

Moon, Katherine A; Zhang, Yiyi; Guallar, Eliseo; Francesconi, Kevin A; Goessler, Walter; Umans, Jason G; Best, Lyle G; Howard, Barbara V; Devereux, Richard B; Okin, Peter M; Navas-Acien, Ana

2018-05-21

Epidemiologic studies suggest that chronic exposure to arsenic is related to cardiovascular disease (CVD), but the pathophysiological link remains uncertain. We evaluated the association of chronic low-moderate arsenic exposure and arsenic metabolism with baseline difference and annual change in ECG measures (QT interval, JT interval, PR interval, QRS duration, and QT dispersion) using linear mixed models in the Strong Heart Study main cohort (N = 1174, median age 55 years) and family study (N = 1695 diabetes-free, median age 36 years). At baseline, arsenic exposure was measured as the sum of inorganic and methylated species in urine (ΣAs) and arsenic metabolism was measured as the relative percentage of arsenic species. Median ΣAs and Bazett heart rate-corrected QT interval (QTc) were 8.6 μg/g creatinine and 424 ms in the main cohort and 4.3 μg/g and 414 ms in the family study, respectively. In the main cohort, a comparison of the highest to lowest ΣAs quartile (>14.4 vs. <5.2 μg/g creatinine) was associated with a 5.3 (95% CI: 1.2, 9.5) ms higher mean baseline QTc interval but no difference in annual change in QTc interval. In the family study, a comparison of the highest to lowest quartile (>7.1 vs. <2.9 μg/g creatinine) was associated with a 3.2 (95% CI: 0.6, 5.7) ms higher baseline QTc interval and a 0.6 (95% CI: 0.04, 1.2) ms larger annual increase in QTc interval. Associations with JTc interval were similar but stronger in magnitude compared to QTc interval. Arsenic exposure was largely not associated with PR interval, QRS duration or QT dispersion. Similar to arsenic exposure, a pattern of lower %MMA and higher %DMA was associated with longer baseline QTc interval in both cohorts and with a larger annual change in QTc interval in the family study. Chronic low-moderate arsenic exposure and arsenic metabolism were associated with prolonged ventricular repolarization. Copyright © 2018 Elsevier Ltd. All rights reserved.

RR-Interval variance of electrocardiogram for atrial fibrillation detection

NASA Astrophysics Data System (ADS)

Nuryani, N.; Solikhah, M.; Nugoho, A. S.; Afdala, A.; Anzihory, E.

2016-11-01

Atrial fibrillation is a serious heart problem originated from the upper chamber of the heart. The common indication of atrial fibrillation is irregularity of R peak-to-R-peak time interval, which is shortly called RR interval. The irregularity could be represented using variance or spread of RR interval. This article presents a system to detect atrial fibrillation using variances. Using clinical data of patients with atrial fibrillation attack, it is shown that the variance of electrocardiographic RR interval are higher during atrial fibrillation, compared to the normal one. Utilizing a simple detection technique and variances of RR intervals, we find a good performance of atrial fibrillation detection.

Estimating the duration of geologic intervals from a small number of age determinations: A challenge common to petrology and paleobiology

NASA Astrophysics Data System (ADS)

Glazner, Allen F.; Sadler, Peter M.

2016-12-01

The duration of a geologic interval, such as the time over which a given volume of magma accumulated to form a pluton, or the lifespan of a large igneous province, is commonly determined from a relatively small number of geochronologic determinations (e.g., 4-10) within that interval. Such sample sets can underestimate the true length of the interval by a significant amount. For example, the average interval determined from a sample of size n = 5, drawn from a uniform random distribution, will underestimate the true interval by 50%. Even for n = 10, the average sample only captures ˜80% of the interval. If the underlying distribution is known then a correction factor can be determined from theory or Monte Carlo analysis; for a uniform random distribution, this factor is n+1n-1. Systematic undersampling of interval lengths can have a large effect on calculated magma fluxes in plutonic systems. The problem is analogous to determining the duration of an extinct species from its fossil occurrences. Confidence interval statistics developed for species origination and extinction times are applicable to the onset and cessation of magmatic events.

Exponential operations and aggregation operators of interval neutrosophic sets and their decision making methods.

PubMed

Ye, Jun

2016-01-01

An interval neutrosophic set (INS) is a subclass of a neutrosophic set and a generalization of an interval-valued intuitionistic fuzzy set, and then the characteristics of INS are independently described by the interval numbers of its truth-membership, indeterminacy-membership, and falsity-membership degrees. However, the exponential parameters (weights) of all the existing exponential operational laws of INSs and the corresponding exponential aggregation operators are crisp values in interval neutrosophic decision making problems. As a supplement, this paper firstly introduces new exponential operational laws of INSs, where the bases are crisp values or interval numbers and the exponents are interval neutrosophic numbers (INNs), which are basic elements in INSs. Then, we propose an interval neutrosophic weighted exponential aggregation (INWEA) operator and a dual interval neutrosophic weighted exponential aggregation (DINWEA) operator based on these exponential operational laws and introduce comparative methods based on cosine measure functions for INNs and dual INNs. Further, we develop decision-making methods based on the INWEA and DINWEA operators. Finally, a practical example on the selecting problem of global suppliers is provided to illustrate the applicability and rationality of the proposed methods.

Determinants and consequences of short birth interval in rural Bangladesh: a cross-sectional study.

PubMed

de Jonge, Hendrik C C; Azad, Kishwar; Seward, Nadine; Kuddus, Abdul; Shaha, Sanjit; Beard, James; Costello, Anthony; Houweling, Tanja A J; Fottrell, Ed

2014-12-24

Short birth intervals are known to have negative effects on pregnancy outcomes. We analysed data from a large population surveillance system in rural Bangladesh to identify predictors of short birth interval and determine consequences of short intervals on pregnancy outcomes. The study was conducted in three districts of Bangladesh - Bogra, Moulavibazar and Faridpur (population 282,643, 54,668 women of reproductive age). We used data between January 2010 and June 2011 from a key informant surveillance system that recorded all births, deaths and stillbirths. Short birth interval was defined as an interval between consecutive births of less than 33 months. Initially, risk factors of a short birth interval were determined using a multivariate mixed effects logistic regression model. Independent risk factors were selected using a priori knowledge from literature review. An adjusted mixed effects logistic regression model was then used to determine the effect of up to 21-, 21-32-, 33-44- and 45-month and higher birth-to-birth intervals on pregnancy outcomes controlling for confounders selected through a directed acyclic graph. We analysed 5,571 second or higher order deliveries. Average birth interval was 55 months and 1368/5571 women (24.6%) had a short birth interval (<33 months). Younger women (AOR 1.11 95% CI 1.08-1.15 per year increase in age), women who started their reproductive life later (AOR 0.95, 0.92-0.98 per year) and those who achieve higher order parities were less likely to experience short birth intervals (AOR 0.28, 0.19-0.41 parity 4 compared to 1). Women who were socioeconomically disadvantaged were more likely to experience a short birth interval (AOR 1.42, 1.22-1.65) and a previous adverse outcome was an important determinant of interval (AOR 2.10, 1.83-2.40). Very short birth intervals of less than 21 months were associated with increased stillbirth rate (AOR 2.13, 95% CI 1.28-3.53) and neonatal mortality (AOR 2.28 95% CI 1.28-4.05). Birth spacing remains a reproductive health problem in Bangladesh. Disadvantaged women are more likely to experience short birth intervals and to have increased perinatal deaths. Research into causal pathways and strategies to improve spacing between pregnancies should be intensified.

RADIO ALTIMETERS

DOEpatents

Bogle, R.W.

1960-11-22

A radio ranging device is described which utilizes a superregenerative oscillator having alternate sending and receiving phases with an intervening ranging interval between said phases, means for varying said ranging interval, means responsive to an on-range noise reduction condition for stopping said means for varying the ranging interval and indicating means coupled to the ranging interval varying means and calibrated in accordance with one-half the product of the ranging interval times the velocity of light whereby the range is indicated.

Fuzzy interval Finite Element/Statistical Energy Analysis for mid-frequency analysis of built-up systems with mixed fuzzy and interval parameters

NASA Astrophysics Data System (ADS)

Yin, Hui; Yu, Dejie; Yin, Shengwen; Xia, Baizhan

2016-10-01

This paper introduces mixed fuzzy and interval parametric uncertainties into the FE components of the hybrid Finite Element/Statistical Energy Analysis (FE/SEA) model for mid-frequency analysis of built-up systems, thus an uncertain ensemble combining non-parametric with mixed fuzzy and interval parametric uncertainties comes into being. A fuzzy interval Finite Element/Statistical Energy Analysis (FIFE/SEA) framework is proposed to obtain the uncertain responses of built-up systems, which are described as intervals with fuzzy bounds, termed as fuzzy-bounded intervals (FBIs) in this paper. Based on the level-cut technique, a first-order fuzzy interval perturbation FE/SEA (FFIPFE/SEA) and a second-order fuzzy interval perturbation FE/SEA method (SFIPFE/SEA) are developed to handle the mixed parametric uncertainties efficiently. FFIPFE/SEA approximates the response functions by the first-order Taylor series, while SFIPFE/SEA improves the accuracy by considering the second-order items of Taylor series, in which all the mixed second-order items are neglected. To further improve the accuracy, a Chebyshev fuzzy interval method (CFIM) is proposed, in which the Chebyshev polynomials is used to approximate the response functions. The FBIs are eventually reconstructed by assembling the extrema solutions at all cut levels. Numerical results on two built-up systems verify the effectiveness of the proposed methods.

Confidence intervals for the population mean tailored to small sample sizes, with applications to survey sampling.

PubMed

Rosenblum, Michael A; Laan, Mark J van der

2009-01-07

The validity of standard confidence intervals constructed in survey sampling is based on the central limit theorem. For small sample sizes, the central limit theorem may give a poor approximation, resulting in confidence intervals that are misleading. We discuss this issue and propose methods for constructing confidence intervals for the population mean tailored to small sample sizes. We present a simple approach for constructing confidence intervals for the population mean based on tail bounds for the sample mean that are correct for all sample sizes. Bernstein's inequality provides one such tail bound. The resulting confidence intervals have guaranteed coverage probability under much weaker assumptions than are required for standard methods. A drawback of this approach, as we show, is that these confidence intervals are often quite wide. In response to this, we present a method for constructing much narrower confidence intervals, which are better suited for practical applications, and that are still more robust than confidence intervals based on standard methods, when dealing with small sample sizes. We show how to extend our approaches to much more general estimation problems than estimating the sample mean. We describe how these methods can be used to obtain more reliable confidence intervals in survey sampling. As a concrete example, we construct confidence intervals using our methods for the number of violent deaths between March 2003 and July 2006 in Iraq, based on data from the study "Mortality after the 2003 invasion of Iraq: A cross sectional cluster sample survey," by Burnham et al. (2006).

Effects of long memory in the order submission process on the properties of recurrence intervals of large price fluctuations

NASA Astrophysics Data System (ADS)

Meng, Hao; Ren, Fei; Gu, Gao-Feng; Xiong, Xiong; Zhang, Yong-Jie; Zhou, Wei-Xing; Zhang, Wei

2012-05-01

Understanding the statistical properties of recurrence intervals (also termed return intervals in econophysics literature) of extreme events is crucial to risk assessment and management of complex systems. The probability distributions and correlations of recurrence intervals for many systems have been extensively investigated. However, the impacts of microscopic rules of a complex system on the macroscopic properties of its recurrence intervals are less studied. In this letter, we adopt an order-driven stock model to address this issue for stock returns. We find that the distributions of the scaled recurrence intervals of simulated returns have a power-law scaling with stretched exponential cutoff and the intervals possess multifractal nature, which are consistent with empirical results. We further investigate the effects of long memory in the directions (or signs) and relative prices of the order flow on the characteristic quantities of these properties. It is found that the long memory in the order directions (Hurst index Hs) has a negligible effect on the interval distributions and the multifractal nature. In contrast, the power-law exponent of the interval distribution increases linearly with respect to the Hurst index Hx of the relative prices, and the singularity width of the multifractal nature fluctuates around a constant value when Hx<0.7 and then increases with Hx. No evident effects of Hs and Hx are found on the long memory of the recurrence intervals. Our results indicate that the nontrivial properties of the recurrence intervals of returns are mainly caused by traders' behaviors of persistently placing new orders around the best bid and ask prices.

Impact of full field digital mammography on the classification and mammographic characteristics of interval breast cancers.

PubMed

Knox, Mark; O'Brien, Angela; Szabó, Endre; Smith, Clare S; Fenlon, Helen M; McNicholas, Michelle M; Flanagan, Fidelma L

2015-06-01

Full field digital mammography (FFDM) is increasingly replacing screen film mammography (SFM) in breast screening programs. Interval breast cancers are an issue in all screening programs and the purpose of our study is to assess the impact of FFDM on the classification of interval breast cancers at independent blind review and to compare the mammographic features of interval cancers at FFDM and SFM. This study included 138 cases of interval breast cancer, 76 following an FFDM screening examination and 62 following screening with SFM. The prior screening mammogram was assessed by each of five consultant breast radiologists who were blinded to the site of subsequent cancer. Subsequent review of the diagnostic mammogram was performed and cases were classified as missed, minimal signs, occult or true interval. Mammographic features of the interval cancer at diagnosis and any abnormality identified on the prior screening mammogram were recorded. The percentages of cancers classified as missed at FFDM and SFM did not differ significantly, 10.5% (8 of 76) at FFDM and 8.1% (5 of 62) at SFM (p=.77). There were significantly less interval cancers presenting as microcalcifications (alone or in association with another abnormality) following screening with FFDM, 16% (12 of 76) than following a SFM examination, 32% (20 of 62) (p=.02). Interval breast cancers continue to pose a problem at FFDM. The switch to FFDM has changed the mammographic presentation of interval breast cancer, with less interval cancers presenting in association with microcalcifications. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Influence of Interpregnancy Interval on Infant Mortality

PubMed Central

MCKINNEY, David; HOUSE, Melissa; CHEN, Aimin; MUGLIA, Louis; DEFRANCO, Emily

2017-01-01

Background In Ohio the infant mortality rate is above the national average and the black infant mortality rate is more than twice the white infant mortality rate. Having a short interpregnancy interval has been shown to correlate with preterm birth and low birth weight, but the effect of short interpregnancy interval on infant mortality is less well established. Objective To quantify the population impact of interpregnancy interval on the risk of infant mortality. Study Design This was a statewide population-based retrospective cohort study of all births (n=1,131,070) and infant mortalities (n=8,152) using linked Ohio birth and infant death records from 1/2007 through 9/2014. For this study we analyzed 5 interpregnancy interval categories: 0 to < 6 months, 6 to < 12 months, 12 to < 24 months, 24 to < 60 months, and ≥ 60 months. The primary outcome for this study was infant mortality. During the study period, 3701 infant mortalities were linked to a live birth certificate with an interpregnancy interval available. We calculated the frequency and relative risk (RR) of infant mortality for each interval compared to a referent interval of 12 to < 24 months. Stratified analyses by maternal race were also performed. Adjusted risks were estimated after accounting for statistically significant and biologically plausible confounding variables. Adjusted relative risk was utilized to calculate the attributable risk percent of short interpregnancy intervals on infant mortality. Results Short interpregnancy intervals were common in Ohio during the study period. 20.5% of all multiparous births followed an interval of < 12 months. The overall infant mortality rate during this time was 7.2 per 1000 live births (6.0 for white mothers and 13.1 for black mothers). Infant mortalities occurred more frequently for births that occurred following short intervals of 0 to < 6 months (9.2 per 1000) and 6 to < 12 months (7.1 per 1000) compared to 12 to < 24 months (5.6 per 1000), (p= <0.001 and <0.001). The highest risk for infant mortality followed interpregnancy intervals of 0 to < 6 months, adjRR 1.32 (95% CI 1.17–1.49) followed by interpregnancy intervals of 6 to < 12 months, adjRR 1.16 (95% CI 1.04–1.30). Analysis stratified by maternal race revealed similar findings. Attributable risk calculation showed that 24.2% of infant mortalities following intervals of 0 to < 6 months and 14.1% with intervals of 6 to < 12 months are attributable to the short interpregnancy interval. By avoiding short interpregnancy intervals of 12 months or less we estimate that in the state of Ohio 31 infant mortalities (20 white and 8 black) per year could have been prevented and the infant mortality rate could have been reduced from 7.2 to 7.0 during this time frame. Conclusion An interpregnancy interval of 12–60 months (1–5 years) between birth and conception of next pregnancy is associated with lowest risk of infant mortality. Public health initiatives and provider counseling to optimize birth spacing has the potential to significantly reduce infant mortality for both white and black mothers. PMID:28034653

Constructing Confidence Intervals for Reliability Coefficients Using Central and Noncentral Distributions.

ERIC Educational Resources Information Center

Weber, Deborah A.

Greater understanding and use of confidence intervals is central to changes in statistical practice (G. Cumming and S. Finch, 2001). Reliability coefficients and confidence intervals for reliability coefficients can be computed using a variety of methods. Estimating confidence intervals includes both central and noncentral distribution approaches.…

The Effects of Interval Duration on Temporal Tracking and Alternation Learning

ERIC Educational Resources Information Center

Ludvig, Elliot A.; Staddon, John E. R.

2005-01-01

On cyclic-interval reinforcement schedules, animals typically show a postreinforcement pause that is a function of the immediately preceding time interval ("temporal tracking"). Animals, however, do not track single-alternation schedules--when two different intervals are presented in strict alternation on successive trials. In this experiment,…

Interresponse Time Structures in Variable-Ratio and Variable-Interval Schedules

ERIC Educational Resources Information Center

Bowers, Matthew T.; Hill, Jade; Palya, William L.

2008-01-01

The interresponse-time structures of pigeon key pecking were examined under variable-ratio, variable-interval, and variable-interval plus linear feedback schedules. Whereas the variable-ratio and variable-interval plus linear feedback schedules generally resulted in a distinct group of short interresponse times and a broad distribution of longer…

Can 3-dimensional power Doppler indices improve the prenatal diagnosis of a potentially morbidly adherent placenta in patients with placenta previa?

PubMed

Haidar, Ziad A; Papanna, Ramesha; Sibai, Baha M; Tatevian, Nina; Viteri, Oscar A; Vowels, Patricia C; Blackwell, Sean C; Moise, Kenneth J

2017-08-01

Traditionally, 2-dimensional ultrasound parameters have been used for the diagnosis of a suspected morbidly adherent placenta previa. More objective techniques have not been well studied yet. The objective of the study was to determine the ability of prenatal 3-dimensional power Doppler analysis of flow and vascular indices to predict the morbidly adherent placenta objectively. A prospective cohort study was performed in women between 28 and 32 gestational weeks with known placenta previa. Patients underwent a two-dimensional gray-scale ultrasound that determined management decisions. 3-Dimensional power Doppler volumes were obtained during the same examination and vascular, flow, and vascular flow indices were calculated after manual tracing of the viewed placenta in the sweep; data were blinded to obstetricians. Morbidly adherent placenta was confirmed by histology. Severe morbidly adherent placenta was defined as increta/percreta on histology, blood loss >2000 mL, and >2 units of PRBC transfused. Sensitivities, specificities, predictive values, and likelihood ratios were calculated. Student t and χ 2 tests, logistic regression, receiver-operating characteristic curves, and intra- and interrater agreements using Kappa statistics were performed. The following results were found: (1) 50 women were studied: 23 had morbidly adherent placenta, of which 12 (52.2%) were severe morbidly adherent placenta; (2) 2-dimensional parameters diagnosed morbidly adherent placenta with a sensitivity of 82.6% (95% confidence interval, 60.4-94.2), a specificity of 88.9% (95% confidence interval, 69.7-97.1), a positive predictive value of 86.3% (95% confidence interval, 64.0-96.4), a negative predictive value of 85.7% (95% confidence interval, 66.4-95.3), a positive likelihood ratio of 7.4 (95% confidence interval, 2.5-21.9), and a negative likelihood ratio of 0.2 (95% confidence interval, 0.08-0.48); (3) mean values of the vascular index (32.8 ± 7.4) and the vascular flow index (14.2 ± 3.8) were higher in morbidly adherent placenta (P < .001); (4) area under the receiver-operating characteristic curve for the vascular and vascular flow indices were 0.99 and 0.97, respectively; (5) the vascular index ≥21 predicted morbidly adherent placenta with a sensitivity and a specificity of 95% (95% confidence interval, 88.2-96.9) and 91%, respectively (95% confidence interval, 87.5-92.4), 92% positive predictive value (95% confidence interval, 85.5-94.3), 90% negative predictive value (95% confidence interval, 79.9-95.3), positive likelihood ratio of 10.55 (95% confidence interval, 7.06-12.75), and negative likelihood ratio of 0.05 (95% confidence interval, 0.03-0.13); and (6) for the severe morbidly adherent placenta, 2-dimensional ultrasound had a sensitivity of 33.3% (95% confidence interval, 11.3-64.6), a specificity of 81.8% (95% confidence interval, 47.8-96.8), a positive predictive value of 66.7% (95% confidence interval, 24.1-94.1), a negative predictive value of 52.9% (95% confidence interval, 28.5-76.1), a positive likelihood ratio of 1.83 (95% confidence interval, 0.41-8.11), and a negative likelihood ratio of 0.81 (95% confidence interval, 0.52-1.26). A vascular index ≥31 predicted the diagnosis of a severe morbidly adherent placenta with a 100% sensitivity (95% confidence interval, 72-100), a 90% specificity (95% confidence interval, 81.7-93.8), an 88% positive predictive value (95% confidence interval, 55.0-91.3), a 100% negative predictive value (95% confidence interval, 90.9-100), a positive likelihood ratio of 10.0 (95% confidence interval, 3.93-16.13), and a negative likelihood ratio of 0 (95% confidence interval, 0-0.34). Intrarater and interrater agreements were 94% (P < .001) and 93% (P < .001), respectively. The vascular index accurately predicts the morbidly adherent placenta in patients with placenta previa. In addition, 3-dimensional power Doppler vascular and vascular flow indices were more predictive of severe cases of morbidly adherent placenta compared with 2-dimensional ultrasound. This objective technique may limit the variations in diagnosing morbidly adherent placenta because of the subjectivity of 2-dimensional ultrasound interpretations. Copyright © 2017 Elsevier Inc. All rights reserved.

Programming with Intervals

NASA Astrophysics Data System (ADS)

Matsakis, Nicholas D.; Gross, Thomas R.

Intervals are a new, higher-level primitive for parallel programming with which programmers directly construct the program schedule. Programs using intervals can be statically analyzed to ensure that they do not deadlock or contain data races. In this paper, we demonstrate the flexibility of intervals by showing how to use them to emulate common parallel control-flow constructs like barriers and signals, as well as higher-level patterns such as bounded-buffer producer-consumer. We have implemented intervals as a publicly available library for Java and Scala.

High-precision optical measurement of the 2S hyperfine interval in atomic hydrogen.

PubMed

Kolachevsky, N; Fischer, M; Karshenboim, S G; Hänsch, T W

2004-01-23

We have applied an optical method to the measurement of the 2S hyperfine interval in atomic hydrogen. The interval has been measured by means of two-photon spectroscopy of the 1S-2S transition on a hydrogen atomic beam shielded from external magnetic fields. The measured value of the 2S hyperfine interval is equal to 177 556 860(16) Hz and represents the most precise measurement of this interval to date. The theoretical evaluation of the specific combination of 1S and 2S hyperfine intervals D21 is in fair agreement (within 1.4 sigma) with the value for D21 deduced from our measurement.

Modeling Relationships Between Flight Crew Demographics and Perceptions of Interval Management

NASA Technical Reports Server (NTRS)

Remy, Benjamin; Wilson, Sara R.

2016-01-01

The Interval Management Alternative Clearances (IMAC) human-in-the-loop simulation experiment was conducted to assess interval management system performance and participants' acceptability and workload while performing three interval management clearance types. Twenty-four subject pilots and eight subject controllers flew ten high-density arrival scenarios into Denver International Airport during two weeks of data collection. This analysis examined the possible relationships between subject pilot demographics on reported perceptions of interval management in IMAC. Multiple linear regression models were created with a new software tool to predict subject pilot questionnaire item responses from demographic information. General patterns were noted across models that may indicate flight crew demographics influence perceptions of interval management.

Temporal Structure of Volatility Fluctuations

NASA Astrophysics Data System (ADS)

Wang, Fengzhong; Yamasaki, Kazuko; Stanley, H. Eugene; Havlin, Shlomo

Volatility fluctuations are of great importance for the study of financial markets, and the temporal structure is an essential feature of fluctuations. To explore the temporal structure, we employ a new approach based on the return interval, which is defined as the time interval between two successive volatility values that are above a given threshold. We find that the distribution of the return intervals follows a scaling law over a wide range of thresholds, and over a broad range of sampling intervals. Moreover, this scaling law is universal for stocks of different countries, for commodities, for interest rates, and for currencies. However, further and more detailed analysis of the return intervals shows some systematic deviations from the scaling law. We also demonstrate a significant memory effect in the return intervals time organization. We find that the distribution of return intervals is strongly related to the correlations in the volatility.

[Heart rate variability study based on a novel RdR RR Intervals Scatter Plot].

PubMed

Lu, Hongwei; Lu, Xiuyun; Wang, Chunfang; Hua, Youyuan; Tian, Jiajia; Liu, Shihai

2014-08-01

On the basis of Poincare scatter plot and first order difference scatter plot, a novel heart rate variability (HRV) analysis method based on scatter plots of RR intervals and first order difference of RR intervals (namely, RdR) was proposed. The abscissa of the RdR scatter plot, the x-axis, is RR intervals and the ordinate, y-axis, is the difference between successive RR intervals. The RdR scatter plot includes the information of RR intervals and the difference between successive RR intervals, which captures more HRV information. By RdR scatter plot analysis of some records of MIT-BIH arrhythmias database, we found that the scatter plot of uncoupled premature ventricular contraction (PVC), coupled ventricular bigeminy and ventricular trigeminy PVC had specific graphic characteristics. The RdR scatter plot method has higher detecting performance than the Poincare scatter plot method, and simpler and more intuitive than the first order difference method.

Hematology and biochemistry reference intervals for Ontario commercial nursing pigs close to the time of weaning

PubMed Central

Perri, Amanda M.; O’Sullivan, Terri L.; Harding, John C.S.; Wood, R. Darren; Friendship, Robert M.

2017-01-01

The evaluation of pig hematology and biochemistry parameters is rarely done largely due to the costs associated with laboratory testing and labor, and the limited availability of reference intervals needed for interpretation. Within-herd and between-herd biological variation of these values also make it difficult to establish reference intervals. Regardless, baseline reference intervals are important to aid veterinarians in the interpretation of blood parameters for the diagnosis and treatment of diseased swine. The objective of this research was to provide reference intervals for hematology and biochemistry parameters of 3-week-old commercial nursing piglets in Ontario. A total of 1032 pigs lacking clinical signs of disease from 20 swine farms were sampled for hematology and iron panel evaluation, with biochemistry analysis performed on a subset of 189 randomly selected pigs. The 95% reference interval, mean, median, range, and 90% confidence intervals were calculated for each parameter. PMID:28373729

Computing the variations in the self-similar properties of the various gait intervals in Parkinson disease patients.

PubMed

Manjeri Keloth, Sana; Arjunan, Sridhar P; Kumar, Dinesh

2017-07-01

This study has investigated the stride, swing, stance and double support intervals of gait for Parkinson's disease (PD) patients with different levels of severity. Self-similar properties of the gait signal were analyzed to investigate the changes in the gait pattern of the healthy and PD patients. To understand the self-similar property, detrended fluctuation analysis was performed. The analysis shows that the PD patients have less defined gait when compared to healthy. The study also shows that among the stance and swing phase of stride interval, the self-similarity is less for swing interval when compared to the stance interval of gait and decreases with the severity of gait. Also, PD patients show decreased self-similar patterns in double support interval of gait. This suggest that there are less rhythmic gait intervals and a sense of urgency to remain in support phase of gait by the PD patients.

CSA-90 Promotes Bone Formation and Mitigates Methicillin-resistant Staphylococcus aureus Infection in a Rat Open Fracture Model.

PubMed

Mills, Rebecca; Cheng, Tegan L; Mikulec, Kathy; Peacock, Lauren; Isaacs, David; Genberg, Carl; Savage, Paul B; Little, David G; Schindeler, Aaron

2018-06-01

Infection of open fractures remains a significant cause of morbidity and mortality to patients worldwide. Early administration of prophylactic antibiotics is known to improve outcomes; however, increasing concern regarding antimicrobial resistance makes finding new compounds for use in such cases a pressing area for further research. CSA-90, a synthetic peptidomimetic compound, has previously demonstrated promising antimicrobial action against Staphylococcus aureus in rat open fractures. However, its efficacy against antibiotic-resistant microorganisms, its potential as a therapeutic agent in addition to its prophylactic effects, and its proosteogenic properties all require further investigation. (1) Does prophylactic treatment with CSA-90 reduce infection rates in a rat open fracture model inoculated with S aureus, methicillin-resistant S aureus (MRSA), and methicillin-resistant Staphylococcus epidermidis (MRSE) as measured by survival, radiographic union, and deep tissue swab cultures? (2) Does CSA-90 reduce infection rates when administered later in the management of an open fracture as measured by survival, radiographic union, and deep tissue swab cultures? (3) Does CSA-90 demonstrate a synergistic proosteogenic effect with bone morphogenetic protein 2 (BMP-2) in a noninfected rat ectopic bone formation assay as assessed by micro-CT bone volume measurement? (4) Can CSA-90 elute and retain its antimicrobial efficacy in vitro when delivered using clinically relevant agents measured using a Kirby-Bauer disc diffusion assay? All in vivo studies were approved by the local animal ethics committee. In the open fracture studies, 12-week-old male Wistar rats underwent open midshaft femoral fractures stabilized with a 1.1-mm Kirschner wire and 10 µg BMP-2 ± 500 µg CSA-90 was applied to the fracture site using a collagen sponge along with 1 x 10 colony-forming units of bacteria (S aureus/MRSA/MRSE; n = 10 per group). In the delayed treatment study, débridement and treatment with 500 µg CSA-90 were performed at Day 1 and Day 5 after injury and bacterial insult (S aureus). All animals were reviewed daily for signs of local infection and/or sepsis. An independent, blinded veterinarian reviewed twice-weekly radiographs, and rats showing osteolysis and/or declining overall health were culled at his instruction. The primary outcome of both fracture studies was fracture infection, incorporating survival, radiographic union, and deep tissue swab cultures. For the ectopic bone formation assay, 0 to 10 µg BMP-2 and 0 to 500 µg CSA-90 were delivered on a collagen sponge into bilateral quadriceps muscle pouches of 8-week-old rats (n = 10 per group). Micro-CT quantification of bone volume and descriptive histologic analysis were performed for all in vivo studies. Modified Kirby-Bauer disc diffusion assays were used to quantify antimicrobial activity in vitro using four different delivery methods, including bone cement. Infection was observed in none of the MRSA inoculated open fractures treated with CSA-90 with 10 of 10 deep tissue swab cultures negative at the time of cull. Median survival was 43 days (range, 11-43 days) in the treated group versus 11 days (range, 8-11 days) in the untreated MRSA inoculated group (p < 0.001). However, delayed débridement and treatment of open fractures with CSA-90 at either Day 1 or Day 5 did not prevent infection, resulting in early culls by Day 21 with positive swab cultures (10 of 10 for each time point). Maximal ectopic bone formation was achieved with 500 μg CSA-90 and 10 μg BMP-2 (mean volume, 9.58 mm; SD, 7.83), creating larger bone nodules than formed with 250 μg CSA-90 and 10 μg BMP-2 (mean volume, 1.7 mm; SD, 1.07; p < 0.001). Disc diffusion assays showed that CSA-90 could successfully elute from four potential delivery agents including calcium sulphate (mean zone of inhibition, 11.35 mm; SD, 0.957) and bone cement (mean, 4.67 mm; SD, 0.516). CSA-90 shows antimicrobial action against antibiotic-resistant Staphylococcal strains in vitro and in an in vivo model of open fracture infection. The antimicrobial properties of CSA-90 combined with further evidence of its proosteogenic potential make it a promising compound to develop further for orthopaedic applications.

Proportion of the Litter Farrowed, Litter Size, and Progesterone and Estradiol Effects on Piglet Birth Intervals and Stillbirths

USDA-ARS?s Scientific Manuscript database

Stillbirth in swine ranges from 2 to 9%, resulting in a significant loss of piglets. Previous studies clearly indicate a relationship between prolonged birth intervals and stillbirth, but factors influencing birth intervals are not fully known. To characterize birth intervals and stillbirth, farrowi...

Fixed-interval performance and self-control in children.

PubMed Central

Darcheville, J C; Rivière, V; Wearden, J H

1992-01-01

Operant responses of 16 children (mean age 6 years and 1 month) were reinforced according to different fixed-interval schedules (with interreinforcer intervals of 20, 30, or 40 s) in which the reinforcers were either 20-s or 40-s presentations of a cartoon. In another procedure, they received training on a self-control paradigm in which both reinforcer delay (0.5 s or 40 s) and reinforcer duration (20 s or 40 s of cartoons) varied, and subjects were offered a choice between various combinations of delay and duration. Individual differences in behavior under the self-control procedure were precisely mirrored by individual differences under the fixed-interval schedule. Children who chose the smaller immediate reinforcer on the self-control procedure (impulsive) produced short postreinforcement pauses and high response rates in the fixed-interval conditions, and both measures changed little with changes in fixed-interval value. Conversely, children who chose the larger delayed reinforcer in the self-control condition (the self-controlled subjects) exhibited lower response rates and long postreinforcement pauses, which changed systematically with changes in the interval, in their fixed-interval performances. PMID:1573372

Defining Incident Cases of Epilepsy in Administrative Data

PubMed Central

Bakaki, Paul M.; Koroukian, Siran M.; Jackson, Leila W.; Albert, Jeffrey M.; Kaiboriboon, Kitti

2013-01-01

Purpose To determine the minimum enrollment duration for identifying incident cases of epilepsy in administrative data. Methods We performed a retrospective dynamic cohort study using Ohio Medicaid data from 1992–2006 to identify a total of 5,037 incident epilepsy cases who had at least 1 year of follow-up prior to epilepsy diagnosis (epilepsy-free interval). The incidence for epilepsy-free intervals from 1 to 8 years, overall and stratified by pre-existing disability status, was examined. The graphical approach between the slopes of incidence estimates and the epilepsy-free intervals was used to identify the minimum epilepsy-free interval that minimized misclassification of prevalent as incident epilepsy cases. Results As the length of epilepsy-free interval increased, the incidence rates decreased. A graphical plot showed that the decline in incidence of epilepsy became nearly flat beyond the third epilepsy-free interval. Conclusion The minimum of 3-year epilepsy-free interval is needed to differentiate incident from prevalent cases in administrative data. Shorter or longer epilepsy-free intervals could result in over- or under-estimation of epilepsy incidence. PMID:23791310

Effect of aeration interval on oxygen consumption and GHG emission during pig manure composting.

PubMed

Zeng, Jianfei; Yin, Hongjie; Shen, Xiuli; Liu, Ning; Ge, Jinyi; Han, Lujia; Huang, Guangqun

2018-02-01

To verify the optimal aeration interval for oxygen supply and consumption and investigate the effect of aeration interval on GHG emission, reactor-scale composting was conducted with different aeration intervals (0, 10, 30 and 50 min). Although O 2 was sufficiently supplied during aeration period, it could be consumed to <10 vol% only when the aeration interval was 50 min, indicating that an aeration interval more than 50 min would be inadvisable. Compared to continuous aeration, reductions of the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent by 22.26-61.36%, 8.24-49.80% and 12.36-53.20%, respectively, was achieved through intermittent aeration. Specifically, both the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent were inversely proportional to the duration of aeration interval (R 2  > 0.902), suggesting that lengthening the duration of aeration interval to some extent could effectively reduce GHG emission. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel approach based on preference-based index for interval bilevel linear programming problem.

PubMed

Ren, Aihong; Wang, Yuping; Xue, Xingsi

2017-01-01

This paper proposes a new methodology for solving the interval bilevel linear programming problem in which all coefficients of both objective functions and constraints are considered as interval numbers. In order to keep as much uncertainty of the original constraint region as possible, the original problem is first converted into an interval bilevel programming problem with interval coefficients in both objective functions only through normal variation of interval number and chance-constrained programming. With the consideration of different preferences of different decision makers, the concept of the preference level that the interval objective function is preferred to a target interval is defined based on the preference-based index. Then a preference-based deterministic bilevel programming problem is constructed in terms of the preference level and the order relation [Formula: see text]. Furthermore, the concept of a preference δ -optimal solution is given. Subsequently, the constructed deterministic nonlinear bilevel problem is solved with the help of estimation of distribution algorithm. Finally, several numerical examples are provided to demonstrate the effectiveness of the proposed approach.

Modelling volatility recurrence intervals in the Chinese commodity futures market

NASA Astrophysics Data System (ADS)

Zhou, Weijie; Wang, Zhengxin; Guo, Haiming

2016-09-01

The law of extreme event occurrence attracts much research. The volatility recurrence intervals of Chinese commodity futures market prices are studied: the results show that the probability distributions of the scaled volatility recurrence intervals have a uniform scaling curve for different thresholds q. So we can deduce the probability distribution of extreme events from normal events. The tail of a scaling curve can be well fitted by a Weibull form, which is significance-tested by KS measures. Both short-term and long-term memories are present in the recurrence intervals with different thresholds q, which denotes that the recurrence intervals can be predicted. In addition, similar to volatility, volatility recurrence intervals also have clustering features. Through Monte Carlo simulation, we artificially synthesise ARMA, GARCH-class sequences similar to the original data, and find out the reason behind the clustering. The larger the parameter d of the FIGARCH model, the stronger the clustering effect is. Finally, we use the Fractionally Integrated Autoregressive Conditional Duration model (FIACD) to analyse the recurrence interval characteristics. The results indicated that the FIACD model may provide a method to analyse volatility recurrence intervals.

Exact Scheffé-type confidence intervals for output from groundwater flow models: 2. Combined use of hydrogeologic information and calibration data

USGS Publications Warehouse

Cooley, Richard L.

1993-01-01

Calibration data (observed values corresponding to model-computed values of dependent variables) are incorporated into a general method of computing exact Scheffé-type confidence intervals analogous to the confidence intervals developed in part 1 (Cooley, this issue) for a function of parameters derived from a groundwater flow model. Parameter uncertainty is specified by a distribution of parameters conditioned on the calibration data. This distribution was obtained as a posterior distribution by applying Bayes' theorem to the hydrogeologically derived prior distribution of parameters from part 1 and a distribution of differences between the calibration data and corresponding model-computed dependent variables. Tests show that the new confidence intervals can be much smaller than the intervals of part 1 because the prior parameter variance-covariance structure is altered so that combinations of parameters that give poor model fit to the data are unlikely. The confidence intervals of part 1 and the new confidence intervals can be effectively employed in a sequential method of model construction whereby new information is used to reduce confidence interval widths at each stage.

Effects of intervals between jumps or bouts on osteogenic response to loading.

PubMed

Umemura, Yoshihisa; Sogo, Naota; Honda, Akiko

2002-10-01

Prolonged loading repetitions can diminish the mechanosensitivity of bones, and increased intervals between loading might restore sensitivity. This study was designed to investigate the effects of intervals between loadings or bouts on osteogenic response. Forty female Fisher 344 rats aged 5 wk were divided into a control group and three exercise groups: 20 jumps in a single bout with a 3-s (S3) or 30-s (S30) jump interval, or 20 jumps in 2 bouts (10 x 2) separated by a 6-h interval with a 3-s jump interval (D3). After 8 wk of training, the bone masses per body weight of the femur and tibia were significantly greater in the three exercise groups than in the control group, and these values were also greater in S30 than in S3, although they were at the same level in D3 and S3. These data suggest that a longer interval (30 s) between individual loading had more effective anabolic effects on bone than a shorter interval (3 s).

Uptake of recommended common reference intervals for chemical pathology in Australia.

PubMed

Jones, Graham Rd; Koetsier, Sabrina

2017-05-01

Background Reference intervals are a vital part of reporting numerical pathology results. It is known, however, that variation in reference intervals between laboratories is common, even when analytical methods support common reference intervals. In response to this, in Australia, the Australasian Association of Clinical Biochemists together with the Royal College of Pathologists of Australasia published in 2014 a set of recommended common reference intervals for 11 common serum analytes (sodium, potassium, chloride, bicarbonate, creatinine male, creatinine female, calcium, calcium adjusted for albumin, phosphate, magnesium, lactate dehydrogenase, alkaline phosphatase and total protein). Methods Uptake of recommended common reference intervals in Australian laboratories was assessed using data from four annual cycles of the RCPAQAP reference intervals external quality assurance programme. Results Over three years, from 2013 to 2016, the use of the recommended upper and lower reference limits has increased from 40% to 83%. Nearly half of the intervals in use by enrolled laboratories in 2016 have been changed in this time period, indicating an active response to the guidelines. Conclusions These data support the activities of the Australasian Association of Clinical Biochemists and Royal College of Pathologists of Australasia in demonstrating a change in laboratory behaviour to reduce unnecessary variation in reference intervals and thus provide a consistent message to doctor and patients irrespective of the laboratory used.

Confidence intervals for distinguishing ordinal and disordinal interactions in multiple regression.

PubMed

Lee, Sunbok; Lei, Man-Kit; Brody, Gene H

2015-06-01

Distinguishing between ordinal and disordinal interaction in multiple regression is useful in testing many interesting theoretical hypotheses. Because the distinction is made based on the location of a crossover point of 2 simple regression lines, confidence intervals of the crossover point can be used to distinguish ordinal and disordinal interactions. This study examined 2 factors that need to be considered in constructing confidence intervals of the crossover point: (a) the assumption about the sampling distribution of the crossover point, and (b) the possibility of abnormally wide confidence intervals for the crossover point. A Monte Carlo simulation study was conducted to compare 6 different methods for constructing confidence intervals of the crossover point in terms of the coverage rate, the proportion of true values that fall to the left or right of the confidence intervals, and the average width of the confidence intervals. The methods include the reparameterization, delta, Fieller, basic bootstrap, percentile bootstrap, and bias-corrected accelerated bootstrap methods. The results of our Monte Carlo simulation study suggest that statistical inference using confidence intervals to distinguish ordinal and disordinal interaction requires sample sizes more than 500 to be able to provide sufficiently narrow confidence intervals to identify the location of the crossover point. (c) 2015 APA, all rights reserved).

Choice in situations of time-based diminishing returns: immediate versus delayed consequences of action.

PubMed Central

Hackenberg, T D; Hineline, P N

1992-01-01

Pigeons chose between two schedules of food presentation, a fixed-interval schedule and a progressive-interval schedule that began at 0 s and increased by 20 s with each food delivery provided by that schedule. Choosing one schedule disabled the alternate schedule and stimuli until the requirements of the chosen schedule were satisfied, at which point both schedules were again made available. Fixed-interval duration remained constant within individual sessions but varied across conditions. Under reset conditions, completing the fixed-interval schedule not only produced food but also reset the progressive interval to its minimum. Blocks of sessions under the reset procedure were interspersed with sessions under a no-reset procedure, in which the progressive schedule value increased independent of fixed-interval choices. Median points of switching from the progressive to the fixed schedule varied systematically with fixed-interval value, and were consistently lower during reset than during no-reset conditions. Under the latter, each subject's choices of the progressive-interval schedule persisted beyond the point at which its requirements equaled those of the fixed-interval schedule at all but the highest fixed-interval value. Under the reset procedure, switching occurred at or prior to that equality point. These results qualitatively confirm molar analyses of schedule preference and some versions of optimality theory, but they are more adequately characterized by a model of schedule preference based on the cumulated values of multiple reinforcers, weighted in inverse proportion to the delay between the choice and each successive reinforcer. PMID:1548449

Indirect methods for reference interval determination - review and recommendations.

PubMed

Jones, Graham R D; Haeckel, Rainer; Loh, Tze Ping; Sikaris, Ken; Streichert, Thomas; Katayev, Alex; Barth, Julian H; Ozarda, Yesim

2018-04-19

Reference intervals are a vital part of the information supplied by clinical laboratories to support interpretation of numerical pathology results such as are produced in clinical chemistry and hematology laboratories. The traditional method for establishing reference intervals, known as the direct approach, is based on collecting samples from members of a preselected reference population, making the measurements and then determining the intervals. An alternative approach is to perform analysis of results generated as part of routine pathology testing and using appropriate statistical techniques to determine reference intervals. This is known as the indirect approach. This paper from a working group of the International Federation of Clinical Chemistry (IFCC) Committee on Reference Intervals and Decision Limits (C-RIDL) aims to summarize current thinking on indirect approaches to reference intervals. The indirect approach has some major potential advantages compared with direct methods. The processes are faster, cheaper and do not involve patient inconvenience, discomfort or the risks associated with generating new patient health information. Indirect methods also use the same preanalytical and analytical techniques used for patient management and can provide very large numbers for assessment. Limitations to the indirect methods include possible effects of diseased subpopulations on the derived interval. The IFCC C-RIDL aims to encourage the use of indirect methods to establish and verify reference intervals, to promote publication of such intervals with clear explanation of the process used and also to support the development of improved statistical techniques for these studies.

The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy.

PubMed

Henselmans, Menno; Schoenfeld, Brad J

2014-12-01

Due to a scarcity of longitudinal trials directly measuring changes in muscle girth, previous recommendations for inter-set rest intervals in resistance training programs designed to stimulate muscular hypertrophy were primarily based on the post-exercise endocrinological response and other mechanisms theoretically related to muscle growth. New research regarding the effects of inter-set rest interval manipulation on resistance training-induced muscular hypertrophy is reviewed here to evaluate current practices and provide directions for future research. Of the studies measuring long-term muscle hypertrophy in groups employing different rest intervals, none have found superior muscle growth in the shorter compared with the longer rest interval group and one study has found the opposite. Rest intervals less than 1 minute can result in acute increases in serum growth hormone levels and these rest intervals also decrease the serum testosterone to cortisol ratio. Long-term adaptations may abate the post-exercise endocrinological response and the relationship between the transient change in hormonal production and chronic muscular hypertrophy is highly contentious and appears to be weak. The relationship between the rest interval-mediated effect on immune system response, muscle damage, metabolic stress, or energy production capacity and muscle hypertrophy is still ambiguous and largely theoretical. In conclusion, the literature does not support the hypothesis that training for muscle hypertrophy requires shorter rest intervals than training for strength development or that predetermined rest intervals are preferable to auto-regulated rest periods in this regard.

Breast screening: What can the interval cancer review teach us? Are we perhaps being a bit too hard on ourselves?

PubMed

Lekanidi, Katerina; Dilks, Phil; Suaris, Tamara; Kennett, Steffan; Purushothaman, Hema

2017-09-01

The aim of this study was to determine the features that make interval cancers apparent on the preceding screening mammogram and determine whether changes in the ways of performing the interval cancer review will affect the true interval cancer rate. This study was approved by the clinical governance committee. Mammograms of women diagnosed with an interval cancer were included in the study if they had been allocated to either the "suspicious signs" group or "subtle signs" group, during the historic interval cancer review. Three radiologists, individually and blinded to the site of interval cancer, reviewed the mammograms and documented the presence, site, characteristics and classification of any abnormality. Findings were compared with the appearances of the abnormality at the site of subsequent cancer development by a different breast radiologist. The chi-squared test was used in the analysis of the results, seeking associations between recall concordance and cancer mammographic or histological characteristics. 111/590 interval cancers fulfilled the study inclusion criteria. In 17% of the cases none of the readers identified the relevant abnormality on the screening mammogram. 1/3 readers identified the relevant lesion in 22% of the cases, 2/3 readers in 28% of cases and all 3 readers in 33% of cases. The commonest unanimously recalled abnormality was microcalcification and the most challenging mammographic abnormality to detect was asymmetric density. We did not find any statistically significant association between recall concordance and time to interval cancer, position of lesion in the breast, breast density or cancer grade. Even the simple step of performing an independent blinded review of interval cancers reduces the rate of interval cancers classified as missed by up to 39%. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects on milk yield of milking interval regularity and teat cup attachment failures with robotic milking systems.

PubMed

Bach, Alex; Busto, Isabel

2005-02-01

A database consisting of 35291 milking records from 83 cows was built over a period of 10 months with the objectives of studying the effect of teat cup attachment failures and milking interval regularity on milk production with an automated milking system (AMS). The database collected records of lactation number, days in milk (DIM), milk production, interval between milkings (for both the entire udder and individual quarters in case of a teat cup attachment failure) and average and peak milk flows for each milking. The weekly coefficient of variation (CV) of milking intervals was used as a measure of milking regularity. DIM, milking intervals, and CV of milking intervals were divided into four categories coinciding with the four quartiles of their respective distributions. The data were analysed by analysis of variance with cow as a random effect and lactation number, DIM, the occurrence of a milking failure, and the intervals between milkings or the weekly CV of milking intervals as fixed effects. The incidence of attachment failures was 7.6% of total milkings. Milk production by quarters affected by a milking failure following the failure was numerically greater owing to the longer interval between milkings. When accounting for the effect of milking intervals, milk production by affected quarters following a milking failure was 26% lower than with regular milkings. However, the decrease in milk production by quarters affected by milking failures was more severe as DIM increased. Average and peak milk flows by quarters affected by a milking failure were lower than when milkings occurred normally. However, milk production recovered its former level within seven milkings following a milking failure. Uneven frequency (weekly CV of milking intervals >27%) decreased daily milk yield, and affected multiparous more negatively than primiparous cows.

Comparison of automated measurements of electrocardiographic intervals and durations by computer-based algorithms of digital electrocardiographs.

PubMed

Kligfield, Paul; Badilini, Fabio; Rowlandson, Ian; Xue, Joel; Clark, Elaine; Devine, Brian; Macfarlane, Peter; de Bie, Johan; Mortara, David; Babaeizadeh, Saeed; Gregg, Richard; Helfenbein, Eric D; Green, Cynthia L

2014-02-01

Automated measurements of electrocardiographic (ECG) intervals are widely used by clinicians for individual patient diagnosis and by investigators in population studies. We examined whether clinically significant systematic differences exist in ECG intervals measured by current generation digital electrocardiographs from different manufacturers and whether differences, if present, are dependent on the degree of abnormality of the selected ECGs. Measurements of RR interval, PR interval, QRS duration, and QT interval were made blindly by 4 major manufacturers of digital electrocardiographs used in the United States from 600 XML files of ECG tracings stored in the US FDA ECG warehouse and released for the purpose of this study by the Cardiac Safety Research Consortium. Included were 3 groups based on expected QT interval and degree of repolarization abnormality, comprising 200 ECGs each from (1) placebo or baseline study period in normal subjects during thorough QT studies, (2) peak moxifloxacin effect in otherwise normal subjects during thorough QT studies, and (3) patients with genotyped variants of congenital long QT syndrome (LQTS). Differences of means between manufacturers were generally small in the normal and moxifloxacin subjects, but in the LQTS patients, differences of means ranged from 2.0 to 14.0 ms for QRS duration and from 0.8 to 18.1 ms for the QT interval. Mean absolute differences between algorithms were similar for QRS duration and QT intervals in the normal and in the moxifloxacin subjects (mean ≤6 ms) but were significantly larger in patients with LQTS. Small but statistically significant group differences in mean interval and duration measurements and means of individual absolute differences exist among automated algorithms of widely used, current generation digital electrocardiographs. Measurement differences, including QRS duration and the QT interval, are greatest for the most abnormal ECGs. © 2014.

Effect of Age and Sex on the QTc Interval in Children and Adolescents With Type 1 and 2 Long-QT Syndrome.

PubMed

Vink, Arja S; Clur, Sally-Ann B; Geskus, Ronald B; Blank, Andreas C; De Kezel, Charlotte C A; Yoshinaga, Masao; Hofman, Nynke; Wilde, Arthur A M; Blom, Nico A

2017-04-01

In congenital long-QT syndrome, age, sex, and genotype have been associated with cardiac events, but their effect on the trend in QTc interval has never been established. We, therefore, aimed to assess the effect of age and sex on the QTc interval in children and adolescents with type 1 (LQT1) and type 2 (LQT2) long-QT syndrome. QTc intervals of 12-lead resting electrocardiograms were determined, and trends over time were analyzed using a linear mixed-effects model. The study included 278 patients with a median follow-up of 4 years (interquartile range, 1-9) and a median number of 6 (interquartile range, 2-10) electrocardiograms per patient. Both LQT1 and LQT2 male patients showed QTc interval shortening after the onset of puberty. In LQT2 male patients, this was preceded by a progressive QTc interval prolongation. In LQT1, after the age of 12 years, male patients had a significantly shorter QTc interval than female patients. In LQT2, during the first years of life and from 14 to 26 years, male patients had a significantly shorter QTc interval than female patients. On the contrary, between 5 and 14 years, LQT2 male patients had significantly longer QTc interval than LQT2 female patients. There is a significant effect of age and sex on the QTc interval in long-QT syndrome, with a unique pattern per genotype. The age of 12 to 14 years is an important transitional period. In the risk stratification and management of long-QT syndrome patients, clinicians should be aware of these age-, sex-, and genotype-related trends in QTc interval and especially the important role of the onset of puberty. © 2017 American Heart Association, Inc.

Confidence intervals for the between-study variance in random-effects meta-analysis using generalised heterogeneity statistics: should we use unequal tails?

PubMed

Jackson, Dan; Bowden, Jack

2016-09-07

Confidence intervals for the between study variance are useful in random-effects meta-analyses because they quantify the uncertainty in the corresponding point estimates. Methods for calculating these confidence intervals have been developed that are based on inverting hypothesis tests using generalised heterogeneity statistics. Whilst, under the random effects model, these new methods furnish confidence intervals with the correct coverage, the resulting intervals are usually very wide, making them uninformative. We discuss a simple strategy for obtaining 95 % confidence intervals for the between-study variance with a markedly reduced width, whilst retaining the nominal coverage probability. Specifically, we consider the possibility of using methods based on generalised heterogeneity statistics with unequal tail probabilities, where the tail probability used to compute the upper bound is greater than 2.5 %. This idea is assessed using four real examples and a variety of simulation studies. Supporting analytical results are also obtained. Our results provide evidence that using unequal tail probabilities can result in shorter 95 % confidence intervals for the between-study variance. We also show some further results for a real example that illustrates how shorter confidence intervals for the between-study variance can be useful when performing sensitivity analyses for the average effect, which is usually the parameter of primary interest. We conclude that using unequal tail probabilities when computing 95 % confidence intervals for the between-study variance, when using methods based on generalised heterogeneity statistics, can result in shorter confidence intervals. We suggest that those who find the case for using unequal tail probabilities convincing should use the '1-4 % split', where greater tail probability is allocated to the upper confidence bound. The 'width-optimal' interval that we present deserves further investigation.

[Primary Study on Predicting the Termination of Paroxysmal Atrial Fibrillation Based on a Novel RdR RR Intervals Scatter Plot].

PubMed

Lu, Hongwei; Zhang, Chenxi; Sun, Ying; Hao, Zhidong; Wang, Chunfang; Tian, Jiajia

2015-08-01

Predicting the termination of paroxysmal atrial fibrillation (AF) may provide a signal to decide whether there is a need to intervene the AF timely. We proposed a novel RdR RR intervals scatter plot in our study. The abscissa of the RdR scatter plot was set to RR intervals and the ordinate was set as the difference between successive RR intervals. The RdR scatter plot includes information of RR intervals and difference between successive RR intervals, which captures more heart rate variability (HRV) information. By RdR scatter plot analysis of one minute RR intervals for 50 segments with non-terminating AF and immediately terminating AF, it was found that the points in RdR scatter plot of non-terminating AF were more decentralized than the ones of immediately terminating AF. By dividing the RdR scatter plot into uniform grids and counting the number of non-empty grids, non-terminating AF and immediately terminating AF segments were differentiated. By utilizing 49 RR intervals, for 20 segments of learning set, 17 segments were correctly detected, and for 30 segments of test set, 20 segments were detected. While utilizing 66 RR intervals, for 18 segments of learning set, 16 segments were correctly detected, and for 28 segments of test set, 20 segments were detected. The results demonstrated that during the last one minute before the termination of paroxysmal AF, the variance of the RR intervals and the difference of the neighboring two RR intervals became smaller. The termination of paroxysmal AF could be successfully predicted by utilizing the RdR scatter plot, while the predicting accuracy should be further improved.

Prevalence, Risk Factors and In-hospital Outcomes of QTc Interval Prolongation in Liver Cirrhosis.

PubMed

Zhao, Jiancheng; Qi, Xingshun; Hou, Feifei; Ning, Zheng; Zhang, Xintong; Deng, Han; Peng, Ying; Li, Jing; Wang, Xiaoxi; Li, Hongyu; Guo, Xiaozhong

2016-09-01

QTc interval prolongation is an electrocardiographic abnormality in liver cirrhosis. The objective of this study was to evaluate the prevalence, risk factors and in-hospital outcomes of QTc interval prolongation in Chinese patients with liver cirrhosis. This was a retrospective analysis of a total of 1,268 patients with liver cirrhosis who were consecutively admitted to our hospital between January 2011 and June 2014. QTc interval data were collected from the medical records. QTc interval prolongation was defined as QTc interval > 440 milliseconds. The prevalence of QTc interval prolongation was 38.2% (485 of 1268). In the entire cohort, the risk factors for QTc interval prolongation included an older age, a higher proportion of alcohol abuse and ascites, higher bilirubin, blood urea nitrogen, creatinine, prothrombin time, international normalized ratio, Child-Pugh score and model for end-stage liver diseases score, and lower red blood cell (RBC), hemoglobin (Hb), albumin (ALB), alanine aminotransferase and calcium. The in-hospital mortality was not significantly different between patients with and without QTc interval prolongation (2.1% versus 1.3%, P = 0.276). In the subgroup analyses of patients with hepatitis B virus or alcohol alone-related liver cirrhosis, the risk factors included higher bilirubin, creatinine, prothrombin time, international normalized ratio, Child-Pugh score and model for end-stage liver diseases score, and lower RBC, Hb and ALB. In the subgroups analyses of patients with acute upper gastrointestinal bleeding or ascites, the risk factors included lower RBC, Hb and ALB. QTc interval prolongation was frequent in liver cirrhosis. Although QTc interval prolongation was positively associated with alcohol-related liver cirrhosis and more severe liver dysfunction, it did not significantly influence the in-hospital mortality. Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

A risk/cost analysis of alternative screening intervals for occupational tuberculosis infection.

PubMed

Nicas, M

1998-02-01

The Centers for Disease Control and Prevention (CDC) recommends that new health care employees receive a baseline skin test for Mycobacterium tuberculosis (M. tb) infection and that testing be repeated periodically. However, CDC does not explain the quantitative basis for its suggested screening intervals. This article examines the efficacy of alternative screening intervals for workers subject to different annual rates of M. tb infection and estimates the costs. An equation is developed for the cumulative risk of tuberculosis (TB) at 12 years given a specified annual rate of infection (ARI), screening interval, and a combined proportion (p) of successful skin testing and antibiotic prophylaxis. Equations for total cost of screening and cost per disease case prevented are provided. Results assume: (a) costs of $10 per skin test and $10,000 per TB disease case; (b) p = 0.88; and (c) and acceptable cumulative TB risk of 1 per 1000. For ARIs that might be deemed low (0.2% to 0.5%) and medium (1%), CDC screening intervals of 12 months and 6-12 months, respectively, minimize the cost per disease case prevented but permit residual disease risks greater than 1 per 1000. Recommended screening intervals are (i) 6 months for low-risk employee groups and (ii) 3 months for medium- and high-risk (e.g., ARIs of > or = 5%) groups. Interval (i) limits risk to 1 per 1000 and is approximately 50% shorter than the CDC interval for a low-risk group. Interval (ii), which is 67% shorter than the CDC interval for medium-risk groups but equal to that recommended for high-risk groups, permits a risk above 1 per 1000, but is likely the shortest feasible interval.

Frequency and Determinants of a Short-Interval Follow-up Recommendation After an Abnormal Screening Mammogram.

PubMed

Pelletier, Eric; Daigle, Jean-Marc; Defay, Fannie; Major, Diane; Guertin, Marie-Hélène; Brisson, Jacques

2016-11-01

After imaging assessment of an abnormal screening mammogram, a follow-up examination 6 months later is recommended to some women. Our aim was to identify which characteristics of lesions, women, and physicians are associated to such short-interval follow-up recommendation in the Quebec Breast Cancer Screening Program. Between 1998 and 2008, 1,839,396 screening mammograms were performed and a total of 114,781 abnormal screens were assessed by imaging only. Multivariate analysis was done with multilevel Poisson regression models with robust variance and generalized linear mixed models. A short-interval follow-up was recommended in 26.7% of assessments with imaging only, representing 2.3% of all screens. Case-mix adjusted proportion of short-interval follow-up recommendations varied substantially across physicians (range: 4%-64%). Radiologists with high recall rates (≥15%) had a high proportion of short-interval follow-up recommendation (risk ratio: 1.82; 95% confidence interval: 1.35-2.45) compared to radiologists with low recall rates (<5%). The adjusted proportion of short-interval follow-up was high (22.8%) even when a previous mammogram was usually available. Short-interval follow-up recommendation at assessment is frequent in this Canadian screening program, even when a previous mammogram is available. Characteristics related to radiologists appear to be key determinants of short-interval follow-up recommendation, rather than characteristics of lesions or patient mix. Given that it can cause anxiety to women and adds pressure on the health system, it appears important to record and report short-interval follow-up and to identify ways to reduce its frequency. Short-interval follow-up recommendations should be considered when assessing the burden of mammography screening. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Effect of increasing the sampling interval to 2 seconds on the radiation dose and accuracy of CT perfusion of the head and neck.

PubMed

Tawfik, Ahmed M; Razek, Ahmed A; Elhawary, Galal; Batouty, Nihal M

2014-01-01

To evaluate the effect of increasing the sampling interval from 1 second (1 image per second) to 2 seconds (1 image every 2 seconds) on computed tomographic (CT) perfusion (CTP) of head and neck tumors. Twenty patients underwent CTP studies of head and neck tumors with images acquired in cine mode for 50 seconds using sampling interval of 1 second. Using deconvolution-based software, analysis of CTP was done with sampling interval of 1 second and then 2 seconds. Perfusion maps representing blood flow, blood volume, mean transit time, and permeability surface area product (PS) were obtained. Quantitative tumor CTP values were compared between the 2 sampling intervals. Two blinded radiologists compared the subjective quality of CTP maps using a 3-point scale between the 2 sampling intervals. Radiation dose parameters were recorded for the 2 sampling interval rates. No significant differences were observed between the means of the 4 perfusion parameters generated using both sampling intervals; all P >0.05. The 95% limits of agreement between the 2 sampling intervals were -65.9 to 48.1) mL/min per 100 g for blood flow, -3.6 to 3.1 mL/100 g for blood volume, -2.9 to 3.8 seconds for mean transit time, and -10.0 to 12.5 mL/min per 100 g for PS. There was no significant difference between the subjective quality scores of CTP maps obtained using the 2 sampling intervals; all P > 0.05. Radiation dose was halved when sampling interval increased from 1 to 2 seconds. Increasing the sampling interval rate to 1 image every 2 seconds does not compromise the image quality and has no significant effect on quantitative perfusion parameters of head and neck tumors. The radiation dose is halved.

Effect of Missing Inter-Beat Interval Data on Heart Rate Variability Analysis Using Wrist-Worn Wearables.

PubMed

Baek, Hyun Jae; Shin, JaeWook

2017-08-15

Most of the wrist-worn devices on the market provide a continuous heart rate measurement function using photoplethysmography, but have not yet provided a function to measure the continuous heart rate variability (HRV) using beat-to-beat pulse interval. The reason for such is the difficulty of measuring a continuous pulse interval during movement using a wearable device because of the nature of photoplethysmography, which is susceptible to motion noise. This study investigated the effect of missing heart beat interval data on the HRV analysis in cases where pulse interval cannot be measured because of movement noise. First, we performed simulations by randomly removing data from the RR interval of the electrocardiogram measured from 39 subjects and observed the changes of the relative and normalized errors for the HRV parameters according to the total length of the missing heart beat interval data. Second, we measured the pulse interval from 20 subjects using a wrist-worn device for 24 h and observed the error value for the missing pulse interval data caused by the movement during actual daily life. The experimental results showed that mean NN and RMSSD were the most robust for the missing heart beat interval data among all the parameters in the time and frequency domains. Most of the pulse interval data could not be obtained during daily life. In other words, the sample number was too small for spectral analysis because of the long missing duration. Therefore, the frequency domain parameters often could not be calculated, except for the sleep state with little motion. The errors of the HRV parameters were proportional to the missing data duration in the presence of missing heart beat interval data. Based on the results of this study, the maximum missing duration for acceptable errors for each parameter is recommended for use when the HRV analysis is performed on a wrist-worn device.

ECG parameters predict left ventricular conduction delay in patients with left ventricular dysfunction.

PubMed

Pastore, Gianni; Maines, Massimiliano; Marcantoni, Lina; Zanon, Francesco; Noventa, Franco; Corbucci, Giorgio; Baracca, Enrico; Aggio, Silvio; Picariello, Claudio; Lanza, Daniela; Rigatelli, Gianluca; Carraro, Mauro; Roncon, Loris; Barold, S Serge

2016-12-01

Estimating left ventricular electrical delay (Q-LV) from a 12-lead ECG may be important in evaluating cardiac resynchronization therapy (CRT). The purpose of this study was to assess the impact of Q-LV interval on ECG configuration. One hundred ninety-two consecutive patients undergoing CRT implantation were divided electrocardiographically into 3 groups: left bundle branch block (LBBB), right bundle branch block (RBBB), and nonspecific intraventricular conduction delay (IVCD). The IVCD group was further subdivided into 81 patients with left (L)-IVCD and 15 patients with right (R)-IVCD (resembling RBBB, but without S wave in leads I and aVL). The Q-LV interval in the different groups and the relationship between ECG parameters and the maximum Q-LV interval were analyzed. Patients with LBBB presented a long Q-LV interval (147.7 ± 14.6 ms, all exceeding cutoff value of 110 ms), whereas RBBB patients presented a very short Q-LV interval (75.2 ± 16.3 ms, all <110 ms). Patients with an IVCD displayed a wide range of Q-LV intervals. In L-IVCD, mid-QRS notching/slurring showed the strongest correlation with a longer Q-LV interval, followed, in decreasing order, by QRS duration >150 ms and intrinsicoid deflection >60 ms. Isolated mid-QRS notching/slurring predicted Q-LV interval >110 ms in 68% of patients. The R-IVCD group presented an unexpectedly longer Q-LV interval (127.0 ± 12.5 ms; 13/15 patients had Q-LV >110 ms). Patients with LBBB have a very prolonged Q-LV interval. Mid-QRS notching in lateral leads strongly predicts a longer Q-LV interval in L-IVCD patients. Patients with R-IVCD constitute a subgroup of patients with a long Q-LV interval. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Interval breast cancer characteristics before, during and after the transition from screen-film to full-field digital screening mammography.

PubMed

van Bommel, Rob M G; Weber, Roy; Voogd, Adri C; Nederend, Joost; Louwman, Marieke W J; Venderink, Dick; Strobbe, Luc J A; Rutten, Matthieu J C; Plaisier, Menno L; Lohle, Paul N; Hooijen, Marianne J H; Tjan-Heijnen, Vivianne C G; Duijm, Lucien E M

2017-05-05

To determine the proportion of "true" interval cancers and tumor characteristics of interval breast cancers prior to, during and after the transition from screen-film mammography screening (SFM) to full-field digital mammography screening (FFDM). We included all women with interval cancers detected between January 2006 and January 2014. Breast imaging reports, biopsy results and breast surgery reports of all women recalled at screening mammography and of all women with interval breast cancers were collected. Two experienced screening radiologists reviewed the diagnostic mammograms, on which the interval cancers were diagnosed, as well as the prior screening mammograms and determined whether or not the interval cancer had been missed on the most recent screening mammogram. If not missed, the cancer was considered an occult ("true") interval cancer. A total of 442 interval cancers had been diagnosed, of which 144 at SFM with a prior SFM (SFM-SFM), 159 at FFDM with a prior SFM (FFDM-SFM) and 139 at FFDM with a prior FFDM (FFDM-FFDM). The transition from SFM to FFDM screening resulted in the diagnosis of more occult ("true") interval cancers at FFDM-SFM than at SFM-SFM (65.4% (104/159) versus 49.3% (71/144), P < 0.01), but this increase was no longer statistically significant in women who had been screened digitally for the second time (57.6% (80/139) at FFDM-FFDM versus 49.3% (71/144) at SFM-SFM). Tumor characteristics were comparable for the three interval cancer cohorts, except of a lower porportion (75.7 and 78.0% versus 67.2% af FFDM-FFDM, P < 0.05) of invasive ductal cancers at FFDM with prior FFDM. An increase in the proportion of occult interval cancers is observed during the transition from SFM to FFDM screening mammography. However, this increase seems temporary and is no longer detectable after the second round of digital screening. Tumor characteristics and type of surgery are comparable for interval cancers detected prior to, during and after the transition from SFM to FFDM screening mammography, except of a lower proportion of invasive ductal cancers after the transition.

[The effect of esmolol on corrected-QT interval, corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients taking an angiotensin-converting enzyme inhibitor].

PubMed

Ceker, Zahit; Takmaz, Suna Akın; Baltaci, Bülent; Başar, Hülya

2015-01-01

The importance of minimizing the exaggerated sympatho-adrenergic responses and QT interval and QT interval dispersion changes that may develop due to laryngoscopy and tracheal intubation during anesthesia induction in the hypertensive patients is clear. Esmolol decreases the hemodynamic response to laryngoscopy and intubation. However, the effect of esmolol in decreasing the prolonged QT interval and QT interval dispersion as induced by laryngoscopy and intubation is controversial. We investigated the effect of esmolol on the hemodynamic, and corrected-QT interval and corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients using angiotensin converting enzyme inhibitors. 60 ASA I-II patients, with essential hypertension using angiotensin converting enzyme inhibitors were included in the study. The esmolol group received esmolol at a bolus dose of 500mcg/kg followed by a 100mcg/kg/min infusion which continued until the 4th min after intubation. The control group received 0.9% saline similar to the esmolol group. The mean blood pressure, heart rate values and the electrocardiogram records were obtained as baseline values before the anesthesia, 5min after esmolol and saline administration, 3min after the induction and 30s, 2min and 4min after intubation. The corrected-QT interval was shorter in the esmolol group (p=0.012), the corrected-QT interval dispersion interval was longer in the control group (p=0.034) and the mean heart rate was higher in the control group (p=0.022) 30s after intubation. The risk of arrhythmia frequency was higher in the control group in the 4-min period following intubation (p=0.038). Endotracheal intubation was found to prolong corrected-QT interval and corrected-QT interval dispersion, and increase the heart rate during anesthesia induction with propofol in hypertensive patients using angiotensin converting enzyme inhibitors. These effects were prevented with esmolol (500mcg/kg bolus, followed by 100mcg/kg/min infusion). During induction, the blood pressure tends to decrease with esmolol where care is needed. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Setting the Revisit Interval in Primary Care

PubMed Central

Schwartz, Lisa M; Woloshin, Steven; Wasson, John H; Renfrew, Roger A; Welch, H Gilbert

1999-01-01

OBJECTIVE Although longitudinal care constitutes the bulk of primary care, physicians receive little guidance on the fundamental question of how to time follow-up visits. We sought to identify important predictors of the revisit interval and to describe the variability in how physicians set these intervals when caring for patients with common medical conditions. DESIGN Cross-sectional survey of physicians performed at the end of office visits for consecutive patients with hypertension, angina, diabetes, or musculoskeletal pain. PARTICIPANTS/SETTING One hundred sixty-four patients under the care of 11 primary care physicians in the Dartmouth Primary Care Cooperative Research Network. MEASUREMENTS The main outcome measures were the variability in mean revisit intervals across physicians and the proportion of explained variance by potential determinants of revisit intervals. We assessed the relation between the revisit interval (dependent variable) and three groups of independent variables, patient characteristics (e.g., age, physician perception of patient health), identification of individual physician, and physician characterization of the visit (e.g., routine visit, visit requiring a change in management, or visit occurring on a “hectic” day), using multiple regression that accounted for the natural grouping of patients within physician. MAIN RESULTS Revisit intervals ranged from 1 week to over 1 year. The most common intervals were 12 and 16 weeks. Physicians’ perception of fair-poor health status and visits involving a change in management were most strongly related to shorter revisit intervals. In multivariate analyses, patient characteristics explained about 18% of the variance in revisit intervals, and adding identification of the individual provider doubled the explained variance to about 40%. Physician characterization of the visit increased explained variance to 57%. The average revisit interval adjusted for patient characteristics for each of the 11 physicians varied from 4 to 20 weeks. Although all physicians lengthened revisit intervals for routine visits and shortened them when changing management, the relative ranking of mean revisit intervals for each physician changed little for different visit characterizations—some physicians were consistently long and others were consistently short. CONCLUSION Physicians vary widely in their recommendations for office revisits. Patient factors accounted for only a small part of this variation. Although physicians responded to visits in predictable ways, each physician appeared to have a unique set point for the length of the revisits interval. PMID:10203635

Gas, water, and oil production from Wattenberg field in the Denver Basin, Colorado

USGS Publications Warehouse

Nelson, Philip H.; Santus, Stephen L.

2011-01-01

Gas, oil, and water production data were compiled from selected wells in two tight gas reservoirs-the Codell-Niobrara interval, comprised of the Codell Sandstone Member of the Carlile Shale and the Niobrara Formation; and the Dakota J interval, comprised mostly of the Muddy (J) Sandstone of the Dakota Group; both intervals are of Cretaceous age-in the Wattenberg field in the Denver Basin of Colorado. Production from each well is represented by two samples spaced five years apart, the first sample typically taken two years after production commenced, which generally was in the 1990s. For each producing interval, summary diagrams and tables of oil-versus-gas production and water-versus-gas production are shown with fluid-production rates, the change in production over five years, the water-gas and oil-gas ratios, and the fluid type. These diagrams and tables permit well-to-well and field-to-field comparisons. Fields producing water at low rates (water dissolved in gas in the reservoir) can be distinguished from fields producing water at moderate or high rates, and the water-gas ratios are quantified. The Dakota J interval produces gas on a per-well basis at roughly three times the rate of the Codell-Niobrara interval. After five years of production, gas data from the second samples show that both intervals produce gas, on average, at about one-half the rate as the first sample. Oil-gas ratios in the Codell-Niobrara interval are characteristic of a retrograde gas and are considerably higher than oil-gas ratios in the Dakota J interval, which are characteristic of a wet gas. Water production from both intervals is low, and records in many wells are discontinuous, particularly in the Codell-Niobrara interval. Water-gas ratios are broadly variable, with some of the variability possibly due to the difficulty of measuring small production rates. Most wells for which water is reported have water-gas ratios exceeding the amount that could exist dissolved in gas at reservoir pressure and temperature. The Codell-Niobrara interval is reported to be overpressured (that is, pressure greater than hydrostatic) whereas the underlying Dakota J interval is underpressured (less than hydrostatic), demonstrating a lack of hydraulic communication between the two intervals despite their proximity over a broad geographical area. The underpressuring in the Dakota J interval has been attributed by others to outcropping strata east of the basin. We agree with this interpretation and postulate that the gas accumulation also may contribute to hydraulic isolation from outcrops immediately west of the basin.