Microorganism immobilization

Science.gov (United States)

Compere, Alicia L.; Griffith, William L.

1981-01-01

Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

Towards a theory of product design specifications

DEFF Research Database (Denmark)

Hansen, Claus Thorp; Andreasen, Mogens Myrup

2004-01-01

, which express the customers¿ need and perception of value. In this paper we will scrutinize this assumption. We outline the roles and tasks of the product design specification in order to identify the requirements on a theory of product design specifications and we identify existing theory elements....... In the design methodology literature we find guidelines and methods to compile a product design specification. The contributions are based on the common underlying assumption that it is meaningful and the only feasible approach to interpret the result of a need analysis into a set of technical specifications...... to build such a theory of product design specifications upon....

Verifying design patterns in Hoare Type Theory

DEFF Research Database (Denmark)

Svendsen, Kasper; Buisse, Alexandre; Birkedal, Lars

In this technical report we document our experiments formally verifying three design patterns in Hoare Type Theory.......In this technical report we document our experiments formally verifying three design patterns in Hoare Type Theory....

System for identification of microorganism and detection of infectious disorder

DEFF Research Database (Denmark)

2013-01-01

Methods for the identification of microorganisms or infectious disorders are disclosed, comprising obtaining a suitable sample from sources such as persons, animals, plants, food, water or soil. The methods also comprise providing tailored nucleic acid substrate(s) designed to react with a type 1...... topoisomerase from one or more microorganism(s) or infectious agent(s), and incubating said substrate with said sample, or extracts or preparations from the sample, so that the substrate is processed by said topoisomerase if said microorganism(s) or infectious agent(s) is present in the sample. Finally......, processed substrates are identified and potentially quantified by one or more of a range of standard molecular biology methods and read-out systems. The identification and potential quantification of microorganisms and infectious agents, including but not limited to Plasmodium falciparum and Mycobacterium...

Algorithms in combinatorial design theory

CERN Document Server

Colbourn, CJ

1985-01-01

The scope of the volume includes all algorithmic and computational aspects of research on combinatorial designs. Algorithmic aspects include generation, isomorphism and analysis techniques - both heuristic methods used in practice, and the computational complexity of these operations. The scope within design theory includes all aspects of block designs, Latin squares and their variants, pairwise balanced designs and projective planes and related geometries.

Developing theory-driven design research

DEFF Research Database (Denmark)

Cash, Philip J.

2018-01-01

Design research is increasingly weak in comparison with other fields; without action to increase scientific, theoretical, and methodological rigour there is a real possibility of the field being superseded and becoming obsolete through lack of impact. The aim of this paper is to show how design r....... I identify key learning indicating future directions for theory-driven design research. I conclude by providing some concrete recommendations for the field of design research and individual design researchers....

Information processing theory in the early design stages

DEFF Research Database (Denmark)

Cash, Philip; Kreye, Melanie

2014-01-01

suggestions for improvements and support. One theory that may be particularly applicable to the early design stages is Information Processing Theory (IPT) as it is linked to the design process with regard to the key concepts considered. IPT states that designers search for information if they perceive......, the new knowledge is shared between the design team to reduce ambiguity with regards to its meaning and to build a shared understanding – reducing perceived uncertainty. Thus, we propose that Information-Processing Theory is suitable to describe designer activity in the early design stages...... uncertainty with regard to the knowledge necessary to solve a design challenge. They then process this information and compare if the new knowledge they have gained covers the previous knowledge gap. In engineering design, uncertainty plays a key role, particularly in the early design stages which has been...

Micro-Organ Device

Science.gov (United States)

Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

2013-01-01

A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

Toward a Theory for the Design of Human Technologies

DEFF Research Database (Denmark)

Simonsen, Jesper; Hertzum, Morten; Nielsen, Jørgen Lerche

2014-01-01

Design is increasingly becoming a part of the university curriculum and research agenda. A theory about the pro-cess and practice of design might be important to estab-lish design as a main subject at universities. We believe it is in the interest of many design communities – not least...... the Participatory Design (PD) community – to engage in theorizing design, on the basis of our understanding of design and design practices. This theory could be posi-tioned as an alternative to other attempts to theorize design, for example the influential efforts of the Information Systems (IS) community. We urge...... the PD community to engage in collective theory building, and we present a framework intended to support our shared reflections on the design of human technologies....

Fate of indicator microorganisms under nutrient management plan conditions.

Science.gov (United States)

Bradford, Scott A; Segal, Eran

2009-01-01

Nutrient management plans (NMPs) for application of wastewater from concentrated animal feeding operations are designed to meet crop water and nutrient requirements, but implicitly assume that pathogenic microorganisms in the wastewater will be retained and die-off in the root zone. A NMP was implemented on a field plot to test this assumption by monitoring the fate of several fecal indicator microorganisms (Enterococcus, fecal coliforms, somatic coliphage, and total Escherichia coli). When well-water and wastewater were applied to meet measured evapotranspiration (ET), little advective transport of the indicator microorganisms occurred below the root zone and the remaining microorganisms rapidly died-off (within 1 mo). Additional experiments were conducted in the laboratory to better quantify microorganism transport and survival in the field soil. Batch survival experiments revealed much more rapid die-off rates for the bacterial indicator microorganisms in native than in sterilized soil, suggesting that biotic factors controlled survival. Saturated column experiments with packed field soil, demonstrated much greater transport potential for somatic coliphage than bacterial indicators (Enterococcus and total E. coli) and that the retention rates for the indicator microorganisms were not log-linear with depth. A worst case transport scenario of ponded infiltration on a large undistributed soil column from the field was also initiated and indicator microorganisms were not detected in the column outflow or in the soil at a depth of 65 cm. All of these observations support the hypothesis that a NMP at this site will protect groundwater supplies from microorganism contamination, especially when applied water and wastewater meet ET.

Radome electromagnetic theory and design

CERN Document Server

Shavit, Reuven

2018-01-01

Radome Electromagnetic Theory and Design explores the theoretical tools and methods required to design radomes that are fully transparent to the electromagnetic energy transmitted or received by the enclosed antenna. A radome is a weatherproof and camouflaged enclosure that protects the enclosed radar or communication antenna, and are typically used on a fixed or moving platform such as an aircraft, ship or missile.

Towards a Design Theory for Collaborative Qualitative Data Analysis

DEFF Research Database (Denmark)

Nielsen, Peter Axel

2016-01-01

This position paper addresses how to develop a design theory to support the collaborative practice of qualitative data analysis. Qualitative researchers face several challenges in making sense of their empirical data and IS-support for this practice can be found in software applications...... such as NVivo, Atlas.ti, and DeDoose. While these software tools have utility and are valuable, they are also limiting – and they are particularly limiting researchers in their collaborative efforts with their co-researchers. In this paper, we investigate a design theory to extend it to support collaboration....... We use this as a stepping stone to discuss how to use a design theory to problematize existing applications and how to extend a design theory by abduction....

Modelling and controller design for a UV disinfection plant

NARCIS (Netherlands)

van Mourik, S.; Geurts, Bernardus J.; Zwart, Heiko J.

2007-01-01

A mathematical model describing fluid flow and concentration dynamics of microorganisms inside a UV photoreactor is developed. Using physical arguments and techniques from system theory, we approximate this model by a first order linear one. For this reduced model, we design a controller. The

General Systems Theory and Instructional Design.

Science.gov (United States)

Salisbury, David F.

The use of general systems theory in the field of instructional systems design (ISD) is explored in this paper. Drawing on work by Young, the writings of 12 representative ISD writers and researchers were surveyed to determine the use of 60 general systems theory concepts by the individual authors. The average number of concepts used by these…

Towards a design theory for reducing aggression in psychiatric facilities

DEFF Research Database (Denmark)

Ulrich, Roger S; Bogren, Lennart; Lundin, Stefan

2012-01-01

The paper proposes a tentative theory for designing psychiatric environments to foster reduced aggression and violence. A basic premise underlying the design theory is that environmental and psycho-social stressors mediate and trigger aggression. The theory posits that aggression will be reduced...... buildings with design guided by the best available evidence and theory can play an important role in reducing the serious patient and staff safety problem of aggressive behavior....... if the facility has been designed with an evidence-based bundle of stress-reducing environmental characteristics that are identified and discussed. To make possible a tentative empirical evaluation of the theory, findings are described from a study that compared aggressive incidents in three Swedish psychiatric...

Making Theory Come Alive through Practice-based Design Research

DEFF Research Database (Denmark)

Markussen, Thomas; Knutz, Eva; Rind Christensen, Poul

The aim of this paper is to demonstrate how practice-based design research is able not only to challenge, but also to push toward further development of some of the basic assumpstions in emotion theories as used within design research. In so doing, we wish to increase knolwedge on a central...... epistemological question for design research, namely how practice-based design research can be a vehicle for the construction of new theory for design research....

Inquiry-Based Laboratory Activity to Investigate Physical Growth Requirements of Microorganisms

Directory of Open Access Journals (Sweden)

Michelle Furlong

2014-08-01

Full Text Available Standard "cookbook" laboratory activities that are used to teach students the optimal physical growth conditions of microorganisms should be modified so that they more effectively foster student's higher order cognitive skills and attract student interest.  This paper describes a laboratory activity that engages students in an inquiry-based approach to studying the physical growth requirements of microorganisms.  In this activity, students design and implement an experiment to obtain pure cultures of specific microorganisms, with distinct growth properties, that are provided to them in a mixed culture.

Activity theory as a challenge to systems design

DEFF Research Database (Denmark)

Bødker, Susanne

1991-01-01

This paper suggests an improvement of the theoretical foundation of information systems research of the 1990s. This foundation is found in human activity theory. The paper deals with how human activity theory can help systems design change, theoretically and practically. Applying activity theory...

Gestalt Theory and Instructional Design.

Science.gov (United States)

Moore, Patrick; Fitz, Chad

1993-01-01

Offers a brief overview of Gestalt theory. Shows how six Gestalt principles (proximity, closure, symmetry, figure-ground segregation, good continuation, and similarity) can be applied to improve a reader's comprehension of a badly designed instruction module that uses several graphics. (SR)

Role and functions of beneficial microorganisms in sustainable aquaculture.

Science.gov (United States)

Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu

2009-08-01

This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.

Nanomaterials-based biosensors for detection of microorganisms and microbial toxins.

Science.gov (United States)

Sutarlie, Laura; Ow, Sian Yang; Su, Xiaodi

2017-04-01

Detection of microorganisms and microbial toxins is important for health and safety. Due to their unique physical and chemical properties, nanomaterials have been extensively used to develop biosensors for rapid detection of microorganisms with microbial cells and toxins as target analytes. In this paper, the design principles of nanomaterials-based biosensors for four selected analyte categories (bacteria cells, toxins, mycotoxins, and protozoa cells), closely associated with the target analytes' properties is reviewed. Five signal transducing methods that are less equipment intensive (colorimetric, fluorimetric, surface enhanced Raman scattering, electrochemical, and magnetic relaxometry methods) is described and compared for their sensory performance (in term oflimit of detection, dynamic range, and response time) for all analyte categories. In the end, the suitability of these five sensing principles for on-site or field applications is discussed. With a comprehensive coverage of nanomaterials, design principles, sensing principles, and assessment on the sensory performance and suitability for on-site application, this review offers valuable insight and perspective for designing suitable nanomaterials-based microorganism biosensors for a given application. Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Theory and design methods of special space orbits

CERN Document Server

Zhang, Yasheng; Zhou, Haijun

2017-01-01

This book focuses on the theory and design of special space orbits. Offering a systematic and detailed introduction to the hovering orbit, spiral cruising orbit, multi-target rendezvous orbit, initiative approaching orbit, responsive orbit and earth pole-sitter orbit, it also discusses the concept, theory, design methods and application of special space orbits, particularly the design and control method based on kinematics and astrodynamics. In addition the book presents the latest research and its application in space missions. It is intended for researchers, engineers and postgraduates, especially those working in the fields of orbit design and control, as well as space-mission planning and research.

Computer-based teaching module design: principles derived from learning theories.

Science.gov (United States)

Lau, K H Vincent

2014-03-01

The computer-based teaching module (CBTM), which has recently gained prominence in medical education, is a teaching format in which a multimedia program serves as a single source for knowledge acquisition rather than playing an adjunctive role as it does in computer-assisted learning (CAL). Despite empirical validation in the past decade, there is limited research into the optimisation of CBTM design. This review aims to summarise research in classic and modern multimedia-specific learning theories applied to computer learning, and to collapse the findings into a set of design principles to guide the development of CBTMs. Scopus was searched for: (i) studies of classic cognitivism, constructivism and behaviourism theories (search terms: 'cognitive theory' OR 'constructivism theory' OR 'behaviourism theory' AND 'e-learning' OR 'web-based learning') and their sub-theories applied to computer learning, and (ii) recent studies of modern learning theories applied to computer learning (search terms: 'learning theory' AND 'e-learning' OR 'web-based learning') for articles published between 1990 and 2012. The first search identified 29 studies, dominated in topic by the cognitive load, elaboration and scaffolding theories. The second search identified 139 studies, with diverse topics in connectivism, discovery and technical scaffolding. Based on their relative representation in the literature, the applications of these theories were collapsed into a list of CBTM design principles. Ten principles were identified and categorised into three levels of design: the global level (managing objectives, framing, minimising technical load); the rhetoric level (optimising modality, making modality explicit, scaffolding, elaboration, spaced repeating), and the detail level (managing text, managing devices). This review examined the literature in the application of learning theories to CAL to develop a set of principles that guide CBTM design. Further research will enable educators to

The design of patient decision support interventions: addressing the theory-practice gap.

Science.gov (United States)

Elwyn, Glyn; Stiel, Mareike; Durand, Marie-Anne; Boivin, Jacky

2011-08-01

Although an increasing number of decision support interventions for patients (including decision aids) are produced, few make explicit use of theory. We argue the importance of using theory to guide design. The aim of this work was to address this theory-practice gap and to examine how a range of selected decision-making theories could inform the design and evaluation of decision support interventions. We reviewed the decision-making literature and selected relevant theories. We assessed their key principles, theoretical pathways and predictions in order to determine how they could inform the design of two core components of decision support interventions, namely, information and deliberation components and to specify theory-based outcome measures. Eight theories were selected: (1) the expected utility theory; (2) the conflict model of decision making; (3) prospect theory; (4) fuzzy-trace theory; (5) the differentiation and consolidation theory; (6) the ecological rationality theory; (7) the rational-emotional model of decision avoidance; and finally, (8) the Attend, React, Explain, Adapt model of affective forecasting. Some theories have strong relevance to the information design (e.g. prospect theory); some are more relevant to deliberation processes (conflict theory, differentiation theory and ecological validity). None of the theories in isolation was sufficient to inform the design of all the necessary components of decision support interventions. It was also clear that most work in theory-building has focused on explaining or describing how humans think rather than on how tools could be designed to help humans make good decisions. It is not surprising therefore that a large theory-practice gap exists as we consider decision support for patients. There was no relevant theory that integrated all the necessary contributions to the task of making good decisions in collaborative interactions. Initiatives such as the International Patient Decision Aids Standards

The application of powerful promoters to enhance gene expression in industrial microorganisms.

Science.gov (United States)

Zhou, Shenghu; Du, Guocheng; Kang, Zhen; Li, Jianghua; Chen, Jian; Li, Huazhong; Zhou, Jingwen

2017-02-01

Production of useful chemicals by industrial microorganisms has been attracting more and more attention. Microorganisms screened from their natural environment usually suffer from low productivity, low stress resistance, and accumulation of by-products. In order to overcome these disadvantages, rational engineering of microorganisms to achieve specific industrial goals has become routine. Rapid development of metabolic engineering and synthetic biology strategies provide novel methods to improve the performance of industrial microorganisms. Rational regulation of gene expression by specific promoters is essential to engineer industrial microorganisms for high-efficiency production of target chemicals. Identification, modification, and application of suitable promoters could provide powerful switches at the transcriptional level for fine-tuning of a single gene or a group of genes, which are essential for the reconstruction of pathways. In this review, the characteristics of promoters from eukaryotic, prokaryotic, and archaea microorganisms are briefly introduced. Identification of promoters based on both traditional biochemical and systems biology routes are summarized. Besides rational modification, de novo design of promoters to achieve gradient, dynamic, and logic gate regulation are also introduced. Furthermore, flexible application of static and dynamic promoters for the rational engineering of industrial microorganisms is highlighted. From the perspective of powerful promoters in industrial microorganisms, this review will provide an extensive description of how to regulate gene expression in industrial microorganisms to achieve more useful goals.

The Application of Layer Theory to Design: The Control Layer

Science.gov (United States)

Gibbons, Andrew S.; Langton, Matthew B.

2016-01-01

A theory of design layers proposed by Gibbons ("An Architectural Approach to Instructional Design." Routledge, New York, 2014) asserts that each layer of an instructional design is related to a body of theory closely associated with the concerns of that particular layer. This study focuses on one layer, the control layer, examining…

A Workshop on Algebraic Design Theory and Hadamard Matrices

CERN Document Server

2015-01-01

This volume develops the depth and breadth of the mathematics underlying the construction and analysis of Hadamard matrices and their use in the construction of combinatorial designs. At the same time, it pursues current research in their numerous applications in security and cryptography, quantum information, and communications. Bridges among diverse mathematical threads and extensive applications make this an invaluable source for understanding both the current state of the art and future directions. The existence of Hadamard matrices remains one of the most challenging open questions in combinatorics. Substantial progress on their existence has resulted from advances in algebraic design theory using deep connections with linear algebra, abstract algebra, finite geometry, number theory, and combinatorics. Hadamard matrices arise in a very diverse set of applications. Starting with applications in experimental design theory and the theory of error-correcting codes, they have found unexpected and important ap...

Approximate design theory for a simple block design with random block effects

OpenAIRE

Christof, Karin

1985-01-01

Approximate design theory for a simple block design with random block effects / K. Christof ; F. Pukelsheim. - In: Linear statistical inference / ed. by T. Calinski ... - Berlin u. a. : Springer, 1985. - S. 20-28. - (Lecture notes in statistics ; 35)

Implementation of static generalized perturbation theory for LWR design applications

International Nuclear Information System (INIS)

Byron, R.F.; White, J.R.

1987-01-01

A generalized perturbation theory (GPT) formulation is developed for application to light water reactor (LWR) design. The extensions made to standard generalized perturbation theory are the treatment of thermal-hydraulic and fission product poisoning feedbacks, and criticality reset. This formulation has been implemented into a standard LWR design code. The method is verified by comparing direct calculations with GPT calculations. Data are presented showing that feedback effects need to be considered when using GPT for LWR problems. Some specific potential applications of this theory to the field of LWR design are discussed

Effects of Atrazine on Soil Microorganisms

Directory of Open Access Journals (Sweden)

Ljiljana Radivojević

2006-01-01

Full Text Available Effects of the herbicide atrazine on soil microorganisms was investigated. Trials were set up in laboratory, on a clay loam soil. Atrazine was applied at 8.0, 40.0 and 80.0 mg/kg soil rates. The abundance of total microorganisms, fungi, actinomycetes, cellulolytic microorganisms and amino-heterotrophs was recorded. Soil samples were collected 1, 7, 14, 21, 30 and 60 days after atrazine treatment for microbiological analyses.The results showed that the intensity of atrazine effect on soil microorganisms depended on treatment rate, exposure time and group of microorganisms. Atrazine had an inhibiting effect on cellulolytic microorganisms and amino-heterotrophs. Initially, it inhibited fungiand actinomycetes but its effect turned into a stimulating one once a population recovered. Atrazine had a stimulating effect on total abundance of microorganisms.

An anthology of theories and models of design philosophy, approaches and empirical explorations

CERN Document Server

Blessing, Lucienne

2014-01-01

While investigations into both theories and models has remained a major strand of engineering design research, current literature sorely lacks a reference book that provides a comprehensive and up-to-date anthology of theories and models, and their philosophical and empirical underpinnings; An Anthology of Theories and Models of Design fills this gap. The text collects the expert views of an international authorship, covering: ·         significant theories in engineering design, including CK theory, domain theory, and the theory of technical systems; ·         current models of design, from a function behavior structure model to an integrated model; ·         important empirical research findings from studies into design; and ·         philosophical underpinnings of design itself. For educators and researchers in engineering design, An Anthology of Theories and Models of Design gives access to in-depth coverage of theoretical and empirical developments in this area; for pr...

Lowlands sociotechnical design theory and lean production

NARCIS (Netherlands)

Christis, Jac; Soepenberg, Erik; Mohr, Bernard J.; van Amelsvoort, Pierre

2015-01-01

Lean Production (LP) can be regarded as a design approach in search of a theoretical foundation. In this paper we show that Lowlands’ Sociotechnical Design Theory (STSL) could function as such a foundation. To reach this goal, we first describe STSL as a system theoretical reformulation of Original

Operational amplifiers theory and design

CERN Document Server

Huijsing, Johan

2017-01-01

This proven textbook guides readers to a thorough understanding of the theory and design of operational amplifiers (OpAmps). The core of the book presents systematically the design of operational amplifiers, classifying them into a periodic system of nine main overall configurations, ranging from one gain stage up to four or more stages. This division enables circuit designers to recognize quickly, understand, and choose optimal configurations. Characterization of operational amplifiers is given by macro models and error matrices, together with measurement techniques for their parameters. Definitions are given for four types of operational amplifiers depending on the grounding of their input and output ports. Many famous designs are evaluated in depth, using a carefully structured approach enhanced by numerous figures. In order to reinforce the concepts introduced and facilitate self-evaluation of design skills, the author includes problems with detailed solutions, as well as simulation exercises. Provides te...

Current trends for improving the design of membrane devices for photoautotrophic biosynthesis is light dependent microorganisms

Directory of Open Access Journals (Sweden)

A. A. Shevtsov

2016-01-01

Full Text Available Modern trends in improving the design of membrane devices for photoautotrophic biosynthesis dependent lighting microorganisms aimed at a significant increase in the productivity of valuable products from biomass of microalgae and obtaining on the basis of their individual useful substances (drugs used in various industries and medicine. In film devices effectively the processes of heat - and mass-exchange with the gas comes into contact with the culture fluid flowing as a film on a transparent film-forming surface is STI in its light intensity and autotrophic biosynthesis occurs only in the presence of a mixture of air with carbon dioxide. Thus, completely eliminated the accumulation of metabolic products due to their continuous removal from film culture liquid with the process gas, which is not typical for devices of other types. Small size membrane bioreactors may increase the degree of saturation of the liquid carbon dioxide with the possibility of changing the concentration of gas in the culture fluid and to ensure the cultivation of microorganisms with a specified biomass yield. At present up to date-developed a significant number of ways to ensure contact of the gas with the liquid (bubbling, gas-lift, mechanical stirring, jet, membrane, etc. on the basis of which an industrial bioreactor, with various "stress" effect. It is believed that for the cultivation of the most optimal are bioreactors with mechanical stirring of the liquid, which allow the greatest productivity of biomass. However, the applied model of a mechanical mixing device to create a work whose cavity of the bioreactor chaotic, disorganized mixing, which contributes to the emergence, insufficient for the sustenance of the cell cultures and microorganisms. Analysis of the interactions of the gas with the liquid film devices showed the need to create a new generation of bioreactor with intensive mass transfer without the possibility of limiting the productivity of

A Design Approach to Teaching Persuasion: Theory and Application.

Science.gov (United States)

Neal, W. Patrick; And Others

One course in persuasion reviews six theories of attitude change--five based on Otto Lerbinger's designs for persuasive communication (cognitive design, stimulus response design, motivational design, personality design, and social design), and a sixth (perceptual design) developed by the instructors. Instruction in each includes a variety of…

Theory and design of CNC systems

CERN Document Server

Suh, Suk-Hwan; Chung, Dae-Hyuk; Stroud, Ian

2008-01-01

Computer Numerical Control (CNC) controllers are high value-added products counting for over 30% of the price of machine tools. The development of CNC technology depends on the integration of technologies from many different industries, and requires strategic long-term support. a oeTheory and Design of CNC Systemsa covers the elements of control, the design of control systems, and modern open-architecture control systems. Topics covered include Numerical Control Kernel (NCK) design of CNC, Programmable Logic Control (PLC), and the Man-Machine Interface (MMI), as well as the major modules for t

Microorganisms in food technology

Energy Technology Data Exchange (ETDEWEB)

Rose, A H

1981-11-01

Man has been using microorganisms for thousands of years to make bread, cheese, beer, wine, etc. Today, microorganisms can be specially grown or genetically manipulated so as to synthesize high-quality proteins even from low-grade basic materials.

Fossil Microorganisms in Archaean

Science.gov (United States)

Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

2006-01-01

Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

Biosurfactants from marine microorganisms

Directory of Open Access Journals (Sweden)

Suppasil Maneerat

2005-11-01

Full Text Available Biosurfactants are the surface-active molecules synthesized by microorganisms. With the advantage of environmental compatibility, the demand for biosurfactants has been steadily increasing and may eventually replace their chemically synthesized counterparts. Marine biosurfactants produced by some marine microorganisms have been paid more attention, particularly for the bioremediation of the sea polluted by crude oil. This review describes screening of biosurfactant-producing microorganisms, the determination of biosurfactant activity as well as the recovery of marine surfactant. The uses of marine biosurfactants for bioremediation are also discussed.

Theory and design of broadband matching networks applied electricity and electronics

CERN Document Server

Chen, Wai-Kai

1976-01-01

Theory and Design of Broadband Matching Networks centers on the network theory and its applications to the design of broadband matching networks and amplifiers. Organized into five chapters, this book begins with a description of the foundation of network theory. Chapter 2 gives a fairly complete exposition of the scattering matrix associated with an n-port network. Chapter 3 considers the approximation problem along with a discussion of the approximating functions. Chapter 4 explains the Youla's theory of broadband matching by illustrating every phase of the theory with fully worked out examp

ARTEMIS: Reinvigorating History and Theory in Art and Design Education

Science.gov (United States)

Janet, Jeff; Miles, Melissa

2009-01-01

ARTEMIS (Art Educational Multiplayer Interactive Space) is an online multi-user virtual environment that is designed around the objects, artefacts, philosophies, personalities and critical discourses of the histories and theories of art and design. Conceived as a means of reinvigorating art history and theory education in the digital age, ARTEMIS…

Applying Semiotic Theories to Graphic Design Education: An Empirical Study on Poster Design Teaching

Science.gov (United States)

Yang, Chao-Ming; Hsu, Tzu-Fan

2015-01-01

The rationales behind design are dissimilar to those behind art. Establishing an adequate theoretical foundation for conducting design education can facilitate scientising design methods. Thus, from the perspectives of the semiotic theories proposed by Saussure and Peirce, we investigated graphic design curricula by performing teaching…

Mechanism design: theory and application to welfare-to-work programs

NARCIS (Netherlands)

Onderstal, S.

2008-01-01

In October 2007, Leonid Hurwicz , Eric Maskin, and Roger Myerson won the Nobel Prize in Economic Sciences "for having laid the foundations of mechanism design theory". My aim is to give you a flavor of what mechanism design theory is and how we can apply it in practice. More in particular, I will

Microorganisms involved in MIC

Energy Technology Data Exchange (ETDEWEB)

Sorensen, K. [Danish Technological Institute (Denmark)

2011-07-01

Microbiologically influenced corrosion (MIC) is a widespread problem that is difficult to detect and assess because of its complex mechanism. This paper presents the involvement of microorganisms in MIC. Some of the mechanisms that cause MIC include hydrogen consumption, production of acids, anode-cathode formation and electron shuttling. A classic bio-corrosive microorganism in the oil and gas industry is sulphate-reducing prokaryotes (SRP). Methanogens also increase corrosion rates in metals. Some of the phylogenetic orders detected while studying SRP and methanogens are archaeoglobales, clostridiales, methanosarcinales and methanothermococcus. There were some implications, such as growth of SRP not being correlated with growth of methanogens; methanogens were included in MIC risk assessment. A few examples are used to display how microorganisms are involved in topside corrosion and microbial community in producing wells. From the study, it can be concluded that, MIC risk assessment includes system data and empirical knowledge of the distribution and number of microorganisms in the system.

Radioresistant microorganisms and food irradiation

Energy Technology Data Exchange (ETDEWEB)

Ito, H [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment

1976-01-01

This paper deals with Micrococcus radiodurans, Arthrobacter radiotolerance, etc., which were isolated and discovered as radioresistant microorganisms. As for the explanation of the mechanism of radioresistance of these microorganisms, the consideration that these organisms have marked repair power of the damaged DNA and have many opportunity to repair the damaged DNA because of their long fission term were cited. The relationship between the radioresistance of microorganisms and food irradiation was also mentioned.

Few microorganisms associated with bacterial vaginosis may constitute the pathologic core

DEFF Research Database (Denmark)

Thorsen, Poul; Jensen, Inge Panum; Jeune, Bernard

1998-01-01

OBJECTIVE: To evaluate the association between various microorganisms isolated from the genital tract in pregnant women with bacterial vaginosis. STUDY DESIGN: A cross-sectional population-based study among pregnant women addressed at their first antenatal visit before 24 full gestational weeks......) between the microorganisms isolated from the lower genital tract in pregnant women with and without clinical diagnosis of bacterial vaginosis. RESULTS: Three thousand five hundred ninety-six (3596) pregnant women were asked to participate. Of the 3596 pregnant women 3174 (88.4%) agreed to participate...

Introduction to TIPS: a theory for creative design

NARCIS (Netherlands)

Sushkov, V.V.; Mars, Nicolaas; Wognum, P.M.

1995-01-01

A highly intriguing problem in combining artificial intelligence and engineering design is automation of the creative and innovative phases of the design process. This paper gives a brief introduction to the theory of inventive problem solving (TIPS) selected as a theoretical basis of the authors'

Interpretive Research Aiming at Theory Building: Adopting and Adapting the Case Study Design

Science.gov (United States)

Diaz Andrade, Antonio

2009-01-01

Although the advantages of case study design are widely recognised, its original positivist underlying assumptions may mislead interpretive researchers aiming at theory building. The paper discusses the limitations of the case study design for theory building and explains how grounded theory systemic process adds to the case study design. The…

Designing the Electronic Classroom: Applying Learning Theory and Ergonomic Design Principles.

Science.gov (United States)

Emmons, Mark; Wilkinson, Frances C.

2001-01-01

Applies learning theory and ergonomic principles to the design of effective learning environments for library instruction. Discusses features of electronic classroom ergonomics, including the ergonomics of physical space, environmental factors, and workstations; and includes classroom layouts. (Author/LRW)

40 CFR 725.85 - Microorganism identity.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Microorganism identity. 725.85 Section... to Information § 725.85 Microorganism identity. (a) Claims applicable to the period prior to... specific microorganism identity at the time of submission of the information. This claim will apply only to...

Some considerations about the theory of intelligent design

Directory of Open Access Journals (Sweden)

JUAN E CARREÑO

2009-01-01

Full Text Available The so-called theory of intelligent design (ID has gained a growing reputation in the Anglo-Saxon culture, becoming a subject of public debate. The approaches that constitute the core of this proposal, however, have been poorly characterized and systematized. The three most significant authors of ID are certainly Michael Behe, William Dembski and Stephen Meyer. Beyond the differences that can be distinguished in the work of each of them, the central fact in their arguments is the complexity of living organisms, which according to these authors, escapes any kind of natural explanation. In effect, according to the authors of ID, the irreducible complexity that can be detected in the natural world would allow to infer design in a scientifically valid way, even though many of them prefer to remain silent regarding the identity and attributes of the designer. We think that under this proposal, remains a deep epistemological confusion, since its very structure combines methodologies that are beyond the scope of historical and natural evolutionary theories. We also reject the claim that ID is a legitimate scientific theory, because it does not exhibit the classical characteristics that a scientific kind of knowledge must have.

Antenna theory: Analysis and design

Science.gov (United States)

Balanis, C. A.

The book's main objective is to introduce the fundamental principles of antenna theory and to apply them to the analysis, design, and measurements of antennas. In a description of antennas, the radiation mechanism is discussed along with the current distribution on a thin wire. Fundamental parameters of antennas are examined, taking into account the radiation pattern, radiation power density, radiation intensity, directivity, numerical techniques, gain, antenna efficiency, half-power beamwidth, beam efficiency, bandwidth, polarization, input impedance, and antenna temperature. Attention is given to radiation integrals and auxiliary potential functions, linear wire antennas, loop antennas, linear and circular arrays, self- and mutual impedances of linear elements and arrays, broadband dipoles and matching techniques, traveling wave and broadband antennas, frequency independent antennas and antenna miniaturization, the geometrical theory of diffraction, horns, reflectors and lens antennas, antenna synthesis and continuous sources, and antenna measurements.

Design Experiments and the Generation of Theory

DEFF Research Database (Denmark)

Nortvig, Anne-Mette

methodology (DBR) and a participatory design approach was used in a case in physiotherapy education from the beginning of the implementation of e-learning in order to create learning designs for the new teaching context and generate theory in relation to this. Ict-based learning designs were created...... in collaboration with teachers and students, and the empirical data are stemming from this work. The research question to discuss in this paper is concerned with the challenges that can arise in a DBR project when the interventions and design cycles do not evolve as planned. The paper therefore argues that it can...

Linking Symbolic Interactionism and Grounded Theory Methods in a Research Design

Directory of Open Access Journals (Sweden)

Jennifer Chamberlain-Salaun

2013-09-01

Full Text Available This article focuses on Corbin and Strauss’ evolved version of grounded theory. In the third edition of their seminal text, Basics of Qualitative Research: Techniques and Procedures for Developing Grounded Theory, the authors present 16 assumptions that underpin their conception of grounded theory methodology. The assumptions stem from a symbolic interactionism perspective of social life, including the themes of meaning, action and interaction, self and perspectives. As research design incorporates both methodology and methods, the authors aim to expose the linkages between the 16 assumptions and essential grounded theory methods, highlighting the application of the latter in light of the former. Analyzing the links between symbolic interactionism and essential grounded theory methods provides novice researchers and researchers new to grounded theory with a foundation from which to design an evolved grounded theory research study.

Heat pipes theory, design and applications

CERN Document Server

Reay, David; Kew, Peter

2013-01-01

Heat Pipes, 6th Edition, takes a highly practical approach to the design and selection of heat pipes, making it an essential guide for practicing engineers and an ideal text for postgraduate students. This new edition has been revised to include new information on the underlying theory of heat pipes and heat transfer, and features fully updated applications, new data sections, and updated chapters on design and electronics cooling. The book is a useful reference for those with experience and an accessible introduction for those approaching the topic for the first time. Contains all informat

Constructal Theory and Aeroelastic Design of Flexible Flying Wing Aircraft

Directory of Open Access Journals (Sweden)

Pezhman Mardanpour

2017-07-01

Full Text Available The aeroelastic behavior of high-aspect-ratio very flexible flying wing is highly affected by the geometric nonlinearities of the aircraft structure. This paper reviews the findings on how these nonlinearities influence the structural and flight dynamics, and it shows that the aeroelastic flight envelope could significantly be extended with proper choices of design parameters such as engine placement. Moreover, in order to investigate the physics behind the effects of design parameters, constructal theory of design is reviewed. The constructal theory advances the philosophy of design as science, it states that the better structural design emerges when stress flow strangulation is avoided. Furthermore, it shows that airplanes, through their evolution, have obeyed theoretical allometric rules that unite their designs.

Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms.

Science.gov (United States)

Soleimaninanadegani, Mohammadreza; Manshad, Soheila

2014-01-01

This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color.

Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms

Science.gov (United States)

Soleimaninanadegani, Mohammadreza

2014-01-01

This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color. PMID:27433516

Information Architecture without Internal Theory: An Inductive Design Process.

Science.gov (United States)

Haverty, Marsha

2002-01-01

Suggests that information architecture design is primarily an inductive process, partly because it lacks internal theory and partly because it is an activity that supports emergent phenomena (user experiences) from basic design components. Suggests a resemblance to Constructive Induction, a design process that locates the best representational…

Design for human factors (DfHF): a grounded theory for integrating human factors into production design processes.

Science.gov (United States)

Village, Judy; Searcy, Cory; Salustri, Filipo; Patrick Neumann, W

2015-01-01

The 'design for human factors' grounded theory explains 'how' human factors (HF) went from a reactive, after-injury programme in safety, to being proactively integrated into each step of the production design process. In this longitudinal case study collaboration with engineers and HF Specialists in a large electronics manufacturer, qualitative data (e.g. meetings, interviews, observations and reflections) were analysed using a grounded theory methodology. The central tenet in the theory is that when HF Specialists acclimated to the engineering process, language and tools, and strategically aligned HF to the design and business goals of the organisation, HF became a means to improve business performance. This led to engineers 'pulling' HF Specialists onto their team. HF targets were adopted into engineering tools to communicate HF concerns quantitatively, drive continuous improvement, visibly demonstrate change and lead to benchmarking. Senior management held engineers accountable for HF as a key performance indicator, thus integrating HF into the production design process. Practitioner Summary: Research and practice lack explanations about how HF can be integrated early in design of production systems. This three-year case study and the theory derived demonstrate how ergonomists changed their focus to align with design and business goals to integrate HF into the design process.

Reflectarray antennas theory, designs, and applications

CERN Document Server

Nayeri, Payam; Elsherbeni, Atef Z

2018-01-01

This book provides engineers with a comprehensive review of the state-of-the-art in reflectarray antenna research and development. The authors describe, in detail, design procedures for a wide range of applications, including broadband, multi-band, multi-beam, contour-beam, beam-scanning, and conformal reflectarray antennas. They provide sufficient coverage of basic reflectarray theory to fully understand reflectarray antenna design and analysis such that the readers can pursue reflectarray research on their own. Throughout the book numerous illustrative design examples including numerical and experimental results are provided. Featuring in-depth theoretical analysis along with practical design examples, Reflectarray Antennas is an excellent text/reference for engineering graduate students, researchers, and engineers in the field of antennas. It belongs on the bookshelves of university libraries, research institutes, and industrial labs and research facilities.

Engineering of microorganisms towards recovery of rare metal ions

Energy Technology Data Exchange (ETDEWEB)

Kuroda, Kouichi; Ueda, Mitsuyoshi [Kyoto Univ. (Japan). Div. of Applied Life Sciences

2010-06-15

The bioadsorption of metal ions using microorganisms is an attractive technology for the recovery of rare metal ions as well as removal of toxic heavy metal ions from aqueous solution. In initial attempts, microorganisms with the ability to accumulate metal ions were isolated from nature and intracellular accumulation was enhanced by the overproduction of metal-binding proteins in the cytoplasm. As an alternative, the cell surface design of microorganisms by cell surface engineering is an emerging strategy for bioadsorption and recovery of metal ions. Cell surface engineering was firstly applied to the construction of a bioadsorbent to adsorb heavy metal ions for bioremediation. Cell surface adsorption of metal ions is rapid and reversible. Therefore, adsorbed metal ions can be easily recovered without cell breakage, and the bioadsorbent can be reused or regenerated. These advantages are suitable for the recovery of rare metal ions. Actually, the cell surface display of a molybdate-binding protein on yeast led to the enhanced adsorption of molybdate, one of the rare metal ions. An additional advantage is that the cell surface display system allows high-throughput screening of protein/peptide libraries owing to the direct evaluation of the displayed protein/peptide without purification and concentration. Therefore, the creation of novel metal-binding protein/ peptide and engineering of microorganisms towards the recovery of rare metal ions could be simultaneously achieved. (orig.)

Bioemulsan Production by Iranian Oil Reservoirs Microorganisms

Directory of Open Access Journals (Sweden)

A Amiriyan, M Mazaheri Assadi, VA Saggadian, A Noohi

2004-10-01

Full Text Available The biosurfactants are believed to be surface active components that are shed into the surrounding medium during the growth of the microorganisms. The oil degrading microorganism Acinetobacter calcoaceticus RAG-1 produces a poly-anionic biosurfactant, hetero-polysaccharide bioemulsifier termed as emulsan which forms and stabilizes oil-water emulsions with a variety of hydrophobic substrates. In the present paper results of the possibility of biosurfactant (Emulsan production by microorganisms isolated from Iranian oil reservoirs is presented. Fourthy three gram negative and gram positive, non fermentative, rod bacilli and coccobacilli shaped baceria were isolated from the oil wells of Bibi Hakimeh, Siri, Maroon, Ilam , East Paydar and West Paydar. Out of the isolated strains, 39 bacterial strains showed beta haemolytic activity, further screening revealed the emulsifying activity and surface tension. 11 out of 43 tested emulsifiers were identified as possible biosurfactant producers and two isolates produced large surface tension reduction, indicating the high probability of biosurfactant production. Further investigation revealed that, two gram negative, oxidase negative, aerobic and coccoid rods isolates were the best producers and hence designated as IL-1, PAY-4. Whole culture broth of isolates reduced surface tension from 68 mN /m to 30 and 29.1mN/m, respectively, and were stable during exposure to high salinity (10%NaCl and elevated temperatures(120C for 15 min .

Heat pump dryers theory, design and industrial applications

CERN Document Server

Alves-Filho, Odilio

2015-01-01

Explore the Social, Technological, and Economic Impact of Heat Pump Drying Heat pump drying is a green technology that aligns with current energy, quality, and environmental concerns, and when compared to conventional drying, delivers similar quality at a lower cost. Heat Pump Dryers: Theory, Design and Industrial Applications details the progression of heat pump drying-from pioneering research and demonstration work to an applied technology-and establishes principles and theories that can aid in the successful design and application of heat pump dryers. Based on the author's personal experience, this book compares heat pump dryers and conventional dryers in terms of performance, quality, removal rate, energy utilization, and the environmental effect of both drying processes. It includes detailed descriptions and layouts of heat pump dryers, outlines the principles of operation, and explains the equations, diagrams, and procedures used to form the basis for heat pump dryer dimensioning and design. The author ...

Gestalt-A Learning Theory for Graphic Design Education

Science.gov (United States)

Jackson, Ian

2008-01-01

This article will begin by seeking to define the notion of learning "by, through" and "from" experience. A linkage will then be established between these notions of experiences and gestalt theory. This will be explored within a subject specific context of graphic design. Links will be highlighted between the inherent nature of graphic design and…

Work Design Theory: A Review and Critique with Implications for Human Resource Development

Science.gov (United States)

Torraco, Richard J.

2005-01-01

Six theoretical perspectives on work design are examined for their contributions to our understanding of how work is organized and designed in organizations: sociotechnical systems theory, process improvement, adaptive structuration theory, the job characteristics model, technostructural change models, and activity theory. A critique of these…

Identification of anaerobic microorganisms for converting kitchen waste to biogas

International Nuclear Information System (INIS)

Amirhossein Malakahmad; Shahrom Mohd Zain; Noor Ezlin Ahmad Basri; Shamsul Rahman Mohamed Kutty; Mohd Hasnain Isa

2010-01-01

Anaerobic digestion process is one of the alternative methods to convert organic waste into methane gas which is a fuel and energy source. Activities of various kinds of microorganisms are the main factor for anaerobic digestion which produces methane gas. Therefore, in this study a modified Anaerobic Baffled Reactor (ABR) with working volume of 50 liters was designed to identify the microorganisms through biogas production. The mixture of 75% kitchen waste and 25% sewage sludge was used as substrate. Observations on microorganisms in the ABR showed that there exists a small amount of protozoa (5%) and fungi (2%) in the system, but almost 93% of the microorganism population consists of bacteria. It is definitely clear that bacteria are responsible for anaerobic biodegradation of kitchen waste. Results show that in the acidification zone of the ABR (front compartments of reactor) fast growing bacteria capable of growth at high substrate levels and reduced pH was dominant. A shift to slower growing scavenging bacteria that grow better at higher pH was occurring towards the end of the reactor. Due to the ability of activity in acetate environment the percentages of Methanococcus, Methanosarcina and Methanotrix were higher than other kinds of methane former in the system. (Author)

Toward a Theory of Representation Design

Science.gov (United States)

1989-05-01

understanding. This report describes research done at the Artificial Inteligence Laboratory of the Massachusetts Institute of Technology. Support for this...AD-A210 885 Technical Report 1128 Toward a Theory of Representation Design Jeffrey Van Baale MIT Artificial Intelligence Laboratory DTIC ELECTE A... Artificial Intelligence Laboratory 545 Technology Square Cambridge, MA 02139 11. CONTROLLING OFFICE NAME AND ADDRESS 11. REPORT DATE Advanced Research

Real-time PCR detection of aldoxime dehydratase genes in nitrile-degrading microorganisms.

Science.gov (United States)

Dooley-Cullinane, Tríona Marie; O'Reilly, Catherine; Coffey, Lee

2017-02-01

Aldoxime dehydratase catalyses the conversion of aldoximes to their corresponding nitriles. Utilization of the aldoxime-nitrile metabolising enzyme pathway can facilitate the move towards a greener chemistry. In this work, a real-time PCR assay was developed for the detection of aldoxime dehydratase genes in aldoxime/nitrile metabolising microorganisms which have been purified from environmental sources. A conventional PCR assay was also designed allowing gene confirmation via sequencing. Aldoxime dehydratase genes were identified in 30 microorganisms across 11 genera including some not previously shown to harbour the gene. The assay displayed a limit of detection of 1 pg/μL DNA or 7 CFU/reaction. This real-time PCR assay should prove valuable in the high-throughput screening of micro-organisms for novel aldoxime dehydratase genes towards pharmaceutical and industrial applications.

Statistical Analysis of Designed Experiments Theory and Applications

CERN Document Server

Tamhane, Ajit C

2012-01-01

A indispensable guide to understanding and designing modern experiments The tools and techniques of Design of Experiments (DOE) allow researchers to successfully collect, analyze, and interpret data across a wide array of disciplines. Statistical Analysis of Designed Experiments provides a modern and balanced treatment of DOE methodology with thorough coverage of the underlying theory and standard designs of experiments, guiding the reader through applications to research in various fields such as engineering, medicine, business, and the social sciences. The book supplies a foundation for the

Theory and Algorithms for Global/Local Design Optimization

National Research Council Canada - National Science Library

Watson, Layne T; Guerdal, Zafer; Haftka, Raphael T

2005-01-01

The motivating application for this research is the global/local optimal design of composite aircraft structures such as wings and fuselages, but the theory and algorithms are more widely applicable...

Bioplastics from microorganisms.

Science.gov (United States)

Luengo, José M; García, Belén; Sandoval, Angel; Naharro, Germán; Olivera, Elías R

2003-06-01

The term 'biomaterials' includes chemically unrelated products that are synthesised by microorganisms (or part of them) under different environmental conditions. One important family of biomaterials is bioplastics. These are polyesters that are widely distributed in nature and accumulate intracellularly in microorganisms in the form of storage granules, with physico-chemical properties resembling petrochemical plastics. These polymers are usually built from hydroxy-acyl-CoA derivatives via different metabolic pathways. Depending on their microbial origin, bioplastics differ in their monomer composition, macromolecular structure and physical properties. Most of them are biodegradable and biocompatible, which makes them extremely interesting from the biotechnological point of view.

Concept Generation for Design Creativity A Systematized Theory and Methodology

CERN Document Server

Taura, Toshiharu

2013-01-01

The concept generation process seems like an intuitional thought: difficult to capture and perform, although everyone is capable of it. It is not an analytical process but a synthetic process which has yet to be clarified. Furthermore, new research methods for investigating the concept generation process—a very difficult task since the concept generation process is driven by inner feelings deeply etched in the mind—are necessary to establish its theory and methodology.  Concept Generation for Design Creativity—A Systematized Theory and Methodology presents the concept generation process both theoretically and methodologically. Theoretically, the concept generation process is discussed by comparing metaphor, abduction, and General Design Theory from the perspective of similarities and dissimilarities. Property mapping, concept blending, and concept integration in thematic relation have been explained methodologically. So far, these theories and methods have been discussed independently, and the relation...

Theory, analysis and design of RF interferometric sensors

CERN Document Server

Nguyen, Cam

2012-01-01

Theory, Analysis and Design of RF Interferometric Sensors presents the theory, analysis and design of RF interferometric sensors. RF interferometric sensors are attractive for various sensing applications that require every fine resolution and accuracy as well as fast speed. The book also presents two millimeter-wave interferometric sensors realized using RF integrated circuits. The developed millimeter-wave homodyne sensor shows sub-millimeter resolution in the order of 0.05 mm without correction for the non-linear phase response of the sensor's quadrature mixer. The designed millimeter-wave double-channel homodyne sensor provides a resolution of only 0.01 mm, or 1/840th of the operating wavelength, and can inherently suppress the non-linearity of the sensor's quadrature mixer. The experimental results of displacement and velocity measurement are presented as a way to demonstrate the sensing ability of the RF interferometry and to illustrate its many possible applications in sensing. The book is succinct, ye...

Microorganism identification technique using radioactive and fluorescent agent

International Nuclear Information System (INIS)

Silman, R.E.

1983-01-01

A method for identifying microorganisms is claimed. An emissive agent is added to a specimen of microorganisms to produce a mix of emissive products. These products are detected and characteristic pattern functioning as an identifier for the microorganisms is derived. The identifier is then compared with identifiers representing known microorganisms

Extraction of design rules from multi-objective design exploration (MODE) using rough set theory

International Nuclear Information System (INIS)

Obayashi, Shigeru

2011-01-01

Multi-objective design exploration (MODE) and its application for design rule extraction are presented. MODE reveals the structure of design space from the trade-off information. The self-organizing map (SOM) is incorporated into MODE as a visual data-mining tool for design space. SOM divides the design space into clusters with specific design features. The sufficient conditions for belonging to a cluster of interest are extracted using rough set theory. The resulting MODE was applied to the multidisciplinary wing design problem, which revealed a cluster of good designs, and we extracted the design rules of such designs successfully.

New Perspective on Visual Communication Design Education: An Empirical Study of Applying Narrative Theory to Graphic Design Courses

Science.gov (United States)

Yang, Chao-Ming; Hsu, Tzu-Fan

2017-01-01

Visual communication design (VCD) is a form of nonverbal communication. The application of relevant linguistic or semiotic theories to VCD education renders graphic design an innovative and scientific discipline. In this study, actual teaching activities were examined to verify the feasibility of applying narrative theory to graphic design…

Activation of inoculum microorganism from dairy cattle feces

Science.gov (United States)

Ayuningtyas, Widya D.; Ridwan, Roni; Joni, I. M.; Marlina, E. T.; Harlia, Ellin

2018-02-01

Coal produces Coal Bed Methane (CBM) which is formed both biogenically and thermogenically. Lignite is not utilized optimally because it has low heat content and productivity time limit that decreases CBM production. In order to utilize lignite waste, adding inoculum consortium microorganism from dairy cattle waste as starter for biogas process can be a solution. This study aimed to produce inoculum consortium microorganism as biogas starter from dairy cattle feces through in vitro activation process by Theoudorou modification method. The research used complete randomized design with 3 replications. The treatments were blank (R0), 100% concentrate (R1), 70% concentrate+30% grass (R2), 70% grass+30% concentrate (R3) and 100% grass (R4). All treatments were added by buffer solution and feces with ratio of 2:1 into 100 ml serum injection bottle with anaerobic conditions. The parameters observed were gas production, pH and gas kinetics (orskov's equation) for 2, 4, 6, 8, 10, 12, 24 and 48 hours. The results showed that the treatment had significant effect (P <0.05) on the observed parameters. The highest total gas production was for R2 and R3 treatments with total production of 91.17 ml and 101.17 ml, pH (6.62 and 6.57), maximum gas production (94.03 and 97.62 ml), speed of gas production (0.066 and 0.084 ml/hour). There is not a significant difference for both the treatments. The source of inoculum consortium microorganisms for biogas starter selected based on the observed parameters and potential availability of proteolytic and fibrocytic microorganisms is R2 (70% concentrate +30% grass).

A Method for Co-Designing Theory-Based Behaviour Change Systems for Health Promotion.

Science.gov (United States)

Janols, Rebecka; Lindgren, Helena

2017-01-01

A methodology was defined and developed for designing theory-based behaviour change systems for health promotion that can be tailored to the individual. Theories from two research fields were combined with a participatory action research methodology. Two case studies applying the methodology were conducted. During and between group sessions the participants created material and designs following the behaviour change strategy themes, which were discussed, analysed and transformed into a design of a behaviour change system. Theories in behavioural change and persuasive technology guided the data collection, data analyses, and the design of a behaviour change system. The methodology has strong emphasis on the target group's participation in the design process. The different aspects brought forward related to behaviour change strategies defined in literature on persuasive technology, and the dynamics of these are associated to needs and motivation defined in literature on behaviour change. It was concluded that the methodology aids the integration of theories into a participatory action research design process, and aids the analyses and motivations of design choices.

The Foundation Role for Theories of Agency in Understanding Information Systems Design

Directory of Open Access Journals (Sweden)

Robert Johnston

2002-11-01

Full Text Available In this paper we argue that theories of agency form a foundation upon which we can build a deeper understanding of information systems design. We do so by firstly recognising that information systems are part of purposeful sociotechnical systems and that consequently theories of agency may help in understanding them. We then present two alternative theories of agency (deliberative and situational, mainly drawn from the robotics and artificial intelligence disciplines, and in doing so, we note that existing information system design methods and ontological studies of those methods implicitly adhere to the deliberative theory of agency. We also note that while there are advantages in specific circumstances from utilising the situated theory of agency in designing complex systems, because of their differing ontological commitments, such systems would be difficult to analyse and evaluate using ontologies currently used in information systems. We then provide evidence that such situational information systems can indeed exist, by giving a specific example (the Kanban system, which has emerged from manufacturing practice. We conclude that information systems are likely to benefit from creating design approaches supporting the production of situational systems.

Teaching Interaction Design and Children: Understanding the Relevance of Theory for Design

Directory of Open Access Journals (Sweden)

Tilde Bekker

2014-08-01

Full Text Available In this paper we address the challenge of teaching interaction design for children’s products especially pertaining to bridging the gap between child development theories and interaction design issues. We describe our experiences from developing a one-week course on interaction design and children, that is part of a competency based Masters program in design. We conclude that key elements in this course, to support learning how to incorporate theoretical knowledge in design, are a providing design tool that covers a child developmental model of four domains (cognitive, social, emotional and physical , such as the Developmentally Situated Design cards for creating child personas and design concepts b using a design exercise c giving students the possibility to work on several iterations d giving students more than one age-group to work with in the project, and e providing the students with an evaluation protocol.

A Fair Accord: Cradle to Cradle as a Design Theory Measured against John Rawls’ Theory of Justice and Immanuel Kant’s Categorical Imperative

Directory of Open Access Journals (Sweden)

Cyrille Gijbels

2010-01-01

Full Text Available This essay explores a specific aspect of the role of attitude in design. The design of the built environment requires us constantly to make aesthetic and ethical judgments; every design decision has to be satisfactorily justified. Surprisingly perhaps, this requires a clear concept of justice against which a design can be grounded. Aesthetic concerns about quality spill into ethical concerns about the rightness of a decision and vice versa. This essay discusses a simple but crucial question: if a designer is aware of Cradle to Cradle as a theory of design but fails to act according to its principles, is it then possible to justify the resultant design? In other words, is Cradle to Cradle as a design theory that most rare of transcendental notions: a Categorical Imperative? Why might it be useful to describe it as such? Does the fact that we do not yet know how to redesign most products and processes according to its principles disqualify the theory? Does a dismissal of the Cradle to Cradle theory inevitably lead to an unfair society? These are serious questions, with interesting answers and far reaching implications for the way we think about design. First we shall explain what Cradle to Cradle means and how it distinguishes itself from other theories of sustainability. Then we shall put that explanation in the context of two ethical theories, first of all John Rawls’ Theory of Justice and second Immanuel Kant’s concept of the Categorical Imperative. After that we shall note a few problems concerning Cradle to Cradle design theory and put those into perspective. This will lead to an important attitudinal conclusion, namely that Cradle to Cradle can legitimately be described as one of those extremely rare cases which deserves universal applicability. We will offer a two-pronged strategy as to how to proceed.

General Systems Theory and Instructional Systems Design.

Science.gov (United States)

Salisbury, David F.

1990-01-01

Describes basic concepts in the field of general systems theory (GST) and identifies commonalities that exist between GST and instructional systems design (ISD). Models and diagrams that depict system elements in ISD are presented, and two matrices that show how GST has been used in ISD literature are included. (11 references) (LRW)

Deconstruction and Graphic Design: History Meets Theory.

Science.gov (United States)

Lupton, Ellen; Miller, J. Abbott

1994-01-01

Considers the reception and use of deconstruction in the recent history of graphic design. Considers the place of graphics within the theory of deconstruction in the work of philosopher Jacques Derrida. Argues that deconstruction is not a style but a mode of questioning through and about the technologies, formal devices, social institutions and…

Extracellular electron transfer mechanisms between microorganisms and minerals

Energy Technology Data Exchange (ETDEWEB)

Shi, Liang; Dong, Hailiang; Reguera, Gemma; Beyenal, Haluk; Lu, Anhuai; Liu, Juan; Yu, Han-Qing; Fredrickson, James K.

2016-08-30

Electrons can be transferred from microorganisms to multivalent metal ions that are associated with minerals and vice versa. As the microbial cell envelope is neither physically permeable to minerals nor electrically conductive, microorganisms have evolved strategies to exchange electrons with extracellular minerals. In this Review, we discuss the molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species. Microorganisms that have extracellular electron transfer capability can be used for biotechnological applications, including bioremediation, biomining and the production of biofuels and nanomaterials.

Towards Cognitive Load Theory as Guideline for Instructional Design in Science Education

Science.gov (United States)

Meissner, Barbara; Bogner, Franz X.

2013-01-01

We applied cognitive load theory in an heuristic out-of-school science lesson. The lesson comprises experiments concerning major attributes of NaCl and was designed for 5th to 8th grade students. Our interest focused on whether cognitive load theory provides sufficient guidelines for instructional design in the field of heuristic science…

General Systems Theory: Application To The Design Of Speech Communication Courses

Science.gov (United States)

Tucker, Raymond K.

1971-01-01

General systems theory can be applied to problems in the teaching of speech communication courses. The author describes general systems theory as it is applied to the designing, conducting and evaluation of speech communication courses. (Author/MS)

Improving the requirements process in Axiomatic Design Theory

DEFF Research Database (Denmark)

Thompson, Mary Kathryn

2013-01-01

This paper introduces a model to integrate the traditional requirements process into Axiomatic Design Theory and proposes a method to structure the requirements process. The method includes a requirements classification system to ensure that all requirements information can be included...... in the Axiomatic Design process, a stakeholder classification system to reduce the chances of excluding one or more key stakeholders, and a table to visualize the mapping between the stakeholders and their requirements....

THE NEW URBAN DESIGN – A SOCIAL THEORY OF ARCHITECTURE ?

Directory of Open Access Journals (Sweden)

Alexander R. Cuthbert

2014-07-01

Full Text Available Abstract Over the last ten years and 1000 pages of text, I outlined a unified field theory which I refer to as The New Urban Design. Possessing the same structure, the three books can be read in series or in parallel, and may best be described as a matrix of possibilities (Cuthbert 2003, 2006, 2011. In this paper I revisit some of the ideas in these texts that need to be more fully developed. Important among them are the undeniable effects of this new field for architecture and urban planning, and an expanded brief on the use of Marxian modes of production to support social analysis in these disciplines. From this perspective we can at least develop some truth as to the historical progress of urban form. In redefining urban design as an independent field, architecture and urban planning subsequently become different regions of thought from what they had previously entertained, namely during the period when they colonised urban design and shared the spoils between them. Extending this argument even further, it is clear that neither discipline, nor the resulting mainstream urban design (i.e. one produced by architects and planners - have had resort to a social theory of their own existence. All so called theories of architecture and urban planning, have failed with good reason. Architecture has relied almost exclusively on aesthetics and technology for its self awareness. Despite the fact that social theory began to penetrate planning theory in the 1970’s, this did not change the idea that planning can have no internally generated theory other than the trivial, since it is an epiphenomenon of the state. It is not an independent factor in urbanisation, and therefore can have no consciousness of its own that is any more than ideological in the Marxist use of the term. In conclusion, the paper suggests that if the weltanshuung of the New Urban Design is persuasive, this has wide ranging implications for education, practice and the development

Designing Opportunities to Learn Mathematics Theory-Building Practices

Science.gov (United States)

Bass, Hyman

2017-01-01

Mathematicians commonly distinguish two modes of work in the discipline: "Problem solving," and "theory building." Mathematics education offers many opportunities to learn problem solving. This paper explores the possibility, and value, of designing instructional activities that provide supported opportunities for students to…

Doppler speedometer for micro-organisms

International Nuclear Information System (INIS)

Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

1996-01-01

Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

Inactivation of Microorganisms

Science.gov (United States)

Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

Research of Applying Semiotic Theory in Interface Design of Mobile Phone

Institute of Scientific and Technical Information of China (English)

王南

2017-01-01

Mobile phone has become the most important daily device in modern society since 21st century. What's more, it will continue to play a significant role in people 's daily life in the foreseeable near future. An outstanding interface design can not only bring convenience to users, but also strengthen users'experience feelings and give customers more fun and joy. This paper is mainly about how to use semiotic theory in the application of phone interface design. By analyzing basic elements of signal trans?mission as well as"Triplet Theory"in semiotics, and practicing every single element in the design, the value of semiotics applica?tion can be clearly shown. That is, to help interface designer understand customers better and fulfill their needs more accurately and to accomplish fantastic designs in mobile interface.

Biofouling of marbles by oxygenic photosynthetic microorganisms.

Science.gov (United States)

Karaca, Zeki; Öztürk, Ayten; Çolak, Emel

2015-08-01

Phototrophic microorganisms disfigure the surfaces of different types of stone. Stone structure is damaged by the activity of photoautotrophic and other microorganisms. However, to date few, investigations have been undertaken into the relationship between microorganisms and the properties of different types of marble. In this study, biological activity of photoautotrophic microorganisms on three types of marble (Yatagan White, Giallo Anticato and Afyon White) was investigated under laboratory conditions over a short period of time. The three types of marble supported the growth of phototrophic microbial communities on their outer and inner layers, turning their original colour from white to a yellowish green colour. The porosity of the marble types facilitated filamentous microbial growth in the presence of water. Scanning electron microscope analysis revealed the accumulation of aggregates such as small spherical, fibrillar, calcified globular bodies on the inner surfaces of the marbles. This suggests that the microscopic characteristics of particular marble types may stimulate the growth of certain types of microorganisms.

Practising what we preach: using cognitive load theory for workshop design and evaluation.

Science.gov (United States)

Naismith, Laura M; Haji, Faizal A; Sibbald, Matthew; Cheung, Jeffrey J H; Tavares, Walter; Cavalcanti, Rodrigo B

2015-12-01

Theory-based instructional design is a top priority in medical education. The goal of this Show and Tell article is to present our theory-driven approach to the design of instruction for clinical educators. We adopted cognitive load theory as a framework to design and evaluate a series of professional development workshops that were delivered at local, national and international academic conferences in 2014. We used two rating scales to measure participants' cognitive load. Participants also provided narrative comments as to how the workshops could be improved. Cognitive load ratings from 59 participants suggested that the workshop design optimized learning by managing complexity for different levels of learners (intrinsic load), stimulating cognitive processing for long-term memory storage (germane load), and minimizing irrelevant distracters (extraneous load). Narrative comments could also be classified as representing intrinsic, extraneous, or germane load, which provided specific directions for ongoing quality improvement. These results demonstrate that a cognitive load theory approach to workshop design and evaluation is feasible and useful in the context of medical education.

Radiation resistance of microorganisms on unsterilized infusion sets

DEFF Research Database (Denmark)

Christensen, E. Ahrensburg; Kristensen, H.; Hoborn, J.

1991-01-01

Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor in a steriliza......Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor...

A theory-based curriculum design for remediation of residents' communication skills.

Science.gov (United States)

Leung, Fok-Han; Martin, Dawn; Batty, Helen

2009-12-01

Residents requiring remediation are often deficient in communication skills, namely clinical interviewing skills. Residents have to digest large amounts of knowledge, and then apply it in a clinical interview. The patient-centered approach, as demonstrated in the Calgary-Cambridge model and Martin's Map, can be difficult to teach. Before implementing a remediation curriculum, the theoretical educational underpinnings must be sound; curriculum evaluation is often expensive. Before establishing metrics for curriculum evaluation, a starting point is to perform a mental experiment to test theoretical adherence. This article describes an experiential remedial curriculum for communication skills. Educational theories of Kolb, Knowles, Bandura, and Bloom are used to design the curriculum into theory-based design components. Kolb's experiential cycle models the natural sequence of experiencing, teaching, and learning interviewing skills. A curriculum structured around this cycle has multiple intercalations with the above educational theories. The design is strengthened by appropriately timed use of education strategies such as learning contracts, taped interviews, simulations, structured reflection, and teacher role modeling. Importantly, it also models the form of the clinical interview format desired. Through understanding and application of contemporary educational theories, a program to remediate interviewing skills can increase its potential for success.

Engineering photosynthesis in plants and synthetic microorganisms.

Science.gov (United States)

Maurino, Veronica G; Weber, Andreas P M

2013-01-01

Photosynthetic organisms, such as cyanobacteria, algae, and plants, sustain life on earth by converting light energy, water, and CO(2) into chemical energy. However, due to global change and a growing human population, arable land is becoming scarce and resources, including water and fertilizers, are becoming exhausted. It will therefore be crucial to design innovative strategies for sustainable plant production to maintain the food and energy bases of human civilization. Several different strategies for engineering improved photosynthesis in crop plants and introducing novel photosynthetic capacity into microorganisms have been reviewed.

The design of patient decision support interventions: addressing the theory-practice gap

NARCIS (Netherlands)

Elwyn, G.; Stiel, M.; Durand, M.A.; Boivin, J.

2011-01-01

BACKGROUND: Although an increasing number of decision support interventions for patients (including decision aids) are produced, few make explicit use of theory. We argue the importance of using theory to guide design. The aim of this work was to address this theory-practice gap and to examine how a

Isolation and characterization of Arctic microorganisms decomposing bioplastics.

Science.gov (United States)

Urbanek, Aneta K; Rymowicz, Waldemar; Strzelecki, Mateusz C; Kociuba, Waldemar; Franczak, Łukasz; Mirończuk, Aleksandra M

2017-12-01

The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.

ORGANIC ACIDS PRODUCTION OF RICE STRAW FERMENTED WITH SEVERAL TYPES OF MICROORGANISM AT DIFFERENT TEMPERATURES

Directory of Open Access Journals (Sweden)

Y. Yanti

2014-10-01

Full Text Available The experiment was carried out to examine the organic acids production of rice straw fermentedwith some types of microorganisms at different temperatures. The experiment was designed as SplitPlot-Completely Randomized Design. The main plot was temperatures treatments (25, 35, 45°C and thesub plot were microorganisms (Control, Control+Mollases, Lactobacillus fermentum, Bacillus subtilis,Bacillus coagulant, Saccharomyces cerevisiae, Aspergillus niger. The highest lactic acid productionswas in B. coagulans treatment at 35°C (53.79 g/kg DM. The highest acetic acid productions was in L.fermentum at 35°C (13.20 g/kg DM, while the highest propionic acid productions were in Controltreatment at 35°C (0.37 g/kg DM.

Uncertainty quantification using evidence theory in multidisciplinary design optimization

International Nuclear Information System (INIS)

Agarwal, Harish; Renaud, John E.; Preston, Evan L.; Padmanabhan, Dhanesh

2004-01-01

Advances in computational performance have led to the development of large-scale simulation tools for design. Systems generated using such simulation tools can fail in service if the uncertainty of the simulation tool's performance predictions is not accounted for. In this research an investigation of how uncertainty can be quantified in multidisciplinary systems analysis subject to epistemic uncertainty associated with the disciplinary design tools and input parameters is undertaken. Evidence theory is used to quantify uncertainty in terms of the uncertain measures of belief and plausibility. To illustrate the methodology, multidisciplinary analysis problems are introduced as an extension to the epistemic uncertainty challenge problems identified by Sandia National Laboratories. After uncertainty has been characterized mathematically the designer seeks the optimum design under uncertainty. The measures of uncertainty provided by evidence theory are discontinuous functions. Such non-smooth functions cannot be used in traditional gradient-based optimizers because the sensitivities of the uncertain measures are not properly defined. In this research surrogate models are used to represent the uncertain measures as continuous functions. A sequential approximate optimization approach is used to drive the optimization process. The methodology is illustrated in application to multidisciplinary example problems

Feasibility of combining linear theory and impact theory methods for the analysis and design of high speed configurations

Science.gov (United States)

Brooke, D.; Vondrasek, D. V.

1978-01-01

The aerodynamic influence coefficients calculated using an existing linear theory program were used to modify the pressures calculated using impact theory. Application of the combined approach to several wing-alone configurations shows that the combined approach gives improved predictions of the local pressure and loadings over either linear theory alone or impact theory alone. The approach not only removes most of the short-comings of the individual methods, as applied in the Mach 4 to 8 range, but also provides the basis for an inverse design procedure applicable to high speed configurations.

Functional microorganisms for functional food quality.

Science.gov (United States)

Gobbetti, M; Cagno, R Di; De Angelis, M

2010-09-01

Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability for probiotic effect, two major options are currently pursued for improving it--to enhance bacterial stress response and to use alternative products for incorporating probiotics (e.g., ice cream, cheeses, cereals, fruit juices, vegetables, and soy beans). Further, it seems that quorum sensing signal molecules released by probiotics may interact with human epithelial cells from intestine thus modulating several physiological functions. Under optimal processing conditions, functional microorganisms contribute to food functionality through their enzyme portfolio and the release of metabolites. Overproduction of free amino acids and vitamins are two classical examples. Besides, bioactive compounds (e.g., peptides, γ-amino butyric acid, and conjugated linoleic acid) may be released during food processing above the physiological threshold and they may exert various in vivo health benefits. Functional microorganisms are even more used in novel strategies for decreasing phenomenon of food intolerance (e.g., gluten intolerance) and allergy. By a critical approach, this review will aim at showing the potential of functional microorganisms for the quality of functional foods.

The biochemistry and molecular biology of xenobiotic polymer degradation by microorganisms.

Science.gov (United States)

Kawai, Fusako

2010-01-01

Research on microbial degradation of xenobiotic polymers has been underway for more than 40 years. It has exploited a new field not only in applied microbiology but also in environmental microbiology, and has greatly contributed to polymer science by initiating the design of biodegradable polymers. Owing to the development of analytical tools and technology, molecular biological and biochemical advances have made it possible to prospect for degrading microorganisms in the environment and to determine the mechanisms involved in biodegradation when xenobiotic polymers are introduced into the environment and are exposed to microbial attack. In this review, the molecular biological and biochemical aspects of the microbial degradation of xenobiotic polymers are summarized, and possible applications of potent microorganisms, enzymes, and genes in environmental biotechnology are suggested.

Cybernetically sound organizational structures II: Relating de Sitter's design theory to Beer's viable system model

NARCIS (Netherlands)

Achterbergh, J.M.I.M.; Vriens, D.J.

2011-01-01

- Purpose – The purpose of this paper is to show how the viable system model (VSM) and de Sitter's design theory can complement each other in the context of the diagnosis and design of viable organizations. - Design/methodology/approach – Key concepts from Beer's model and de Sitter's design theory

[Characteristics of proteins synthesized by hydrogen-oxidizing microorganisms].

Science.gov (United States)

Volova, T G; Barashkov, V A

2010-01-01

The study was conducted to determine the biological value of proteins synthesized by hydrogen-oxidizing microorganisms--the hydrogen bacteria Alcaligenes eutrophus Z1 and Ralstonia eutropha B5786 and the CO-resistant strain of carboxydobacterium Seliberia carboxydohydrogena Z1062. Based on a number of significant parameters characterizing the biological value of a product, the proteins of hydrogen-oxidizing microorganisms have been found to occupy an intermediate position between traditional animal and plant proteins. The high total protein in biomass of these microorganisms, their complete amino acid content, and availability to proteolytic enzymes allow for us to consider these microorganisms as potential protein producers.

Mechanisms of nickel toxicity in microorganisms

Science.gov (United States)

Macomber, Lee

2014-01-01

Summary Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological concern. To date, the mechanisms of nickel toxicity in microorganisms and higher eukaryotes are poorly understood. In this review, we summarize nickel homeostasis processes used by microorganisms and highlight in vivo and in vitro effects of exposure to elevated concentrations of nickel. On the basis of this evidence we propose four mechanisms of nickel toxicity: 1) nickel replaces the essential metal of metalloproteins, 2) nickel binds to catalytic residues of non-metalloenzymes; 3) nickel binds outside the catalytic site of an enzyme to inhibit allosterically, and 4) nickel indirectly causes oxidative stress. PMID:21799955

Time-domain ultra-wideband radar, sensor and components theory, analysis and design

CERN Document Server

Nguyen, Cam

2014-01-01

This book presents the theory, analysis, and design of ultra-wideband (UWB) radar and sensor systems (in short, UWB systems) and their components. UWB systems find numerous applications in the military, security, civilian, commercial and medicine fields. This book addresses five main topics of UWB systems: System Analysis, Transmitter Design, Receiver Design, Antenna Design and System Integration and Test. The developments of a practical UWB system and its components using microwave integrated circuits, as well as various measurements, are included in detail to demonstrate the theory, analysis and design technique. Essentially, this book will enable the reader to design their own UWB systems and components. In the System Analysis chapter, the UWB principle of operation as well as the power budget analysis and range resolution analysis are presented. In the UWB Transmitter Design chapter, the design, fabrication and measurement of impulse and monocycle pulse generators are covered. The UWB Receiver Design cha...

Game Theory and Risk-Based Levee System Design

Science.gov (United States)

Hui, R.; Lund, J. R.; Madani, K.

2014-12-01

Risk-based analysis has been developed for optimal levee design for economic efficiency. Along many rivers, two levees on opposite riverbanks act as a simple levee system. Being rational and self-interested, land owners on each river bank would tend to independently optimize their levees with risk-based analysis, resulting in a Pareto-inefficient levee system design from the social planner's perspective. Game theory is applied in this study to analyze decision making process in a simple levee system in which the land owners on each river bank develop their design strategies using risk-based economic optimization. For each land owner, the annual expected total cost includes expected annual damage cost and annualized construction cost. The non-cooperative Nash equilibrium is identified and compared to the social planner's optimal distribution of flood risk and damage cost throughout the system which results in the minimum total flood cost for the system. The social planner's optimal solution is not feasible without appropriate level of compensation for the transferred flood risk to guarantee and improve conditions for all parties. Therefore, cooperative game theory is then employed to develop an economically optimal design that can be implemented in practice. By examining the game in the reversible and irreversible decision making modes, the cost of decision making myopia is calculated to underline the significance of considering the externalities and evolution path of dynamic water resource problems for optimal decision making.

Theory and design of heat exchanger : Double pipe and heat exchanger in abnormal condition

International Nuclear Information System (INIS)

Min, Ui Dong

1996-02-01

This book introduces theory and design of heat exchanger, which includes HTRI program, multiple tube heat exchanger external heating, theory of heat transfer, basis of design of heat exchanger, two-phase flow, condensation, boiling, material of heat exchanger, double pipe heat exchanger like hand calculation, heat exchanger in abnormal condition such as Jackets Vessel, and Coiled Vessel, design and summary of steam tracing.

ORGANIC ACIDS PRODUCTION OF RICE STRAW FERMENTED WITH SEVERAL TYPES OF MICROORGANISM AT DIFFERENT TEMPERATURES

Directory of Open Access Journals (Sweden)

Surahmanto

2012-09-01

Full Text Available The experiment was carried out to examine the organic acids production of rice straw fermented with some types of microorganisms at different temperatures. The experiment was designed as Split Plot-Completely Randomized Design. The main plot was temperatures treatments (25, 35, 45°C and the sub plot were microorganisms (Control, Control+Mollases, Lactobacillus fermentum, Bacillus subtilis, Bacillus coagulant, Saccharomyces cerevisiae, Aspergillus niger. The highest lactic acid productions was in B. coagulans treatment at 35°C (53.79 g/kg DM. The highest acetic acid productions was in L. fermentum at 35°C (13.20 g/kg DM, while the highest propionic acid productions were in Control treatment at 35°C (0.37 g/kg DM.

Development of microorganisms for cellulose-biofuel consolidated bioprocessings: metabolic engineers’ tricks

Directory of Open Access Journals (Sweden)

Roberto Mazzoli

2012-10-01

Full Text Available Cellulose waste biomass is the most abundant and attractive substrate for "biorefinery strategies" that are aimed to produce high-value products (e.g. solvents, fuels, building blocks by economically and environmentally sustainable fermentation processes. However, cellulose is highly recalcitrant to biodegradation and its conversion by biotechnological strategies currently requires economically inefficient multistep industrial processes. The need for dedicated cellulase production continues to be a major constraint to cost-effective processing of cellulosic biomass.Research efforts have been aimed at developing recombinant microorganisms with suitable characteristics for single step biomass fermentation (consolidated bioprocessing, CBP. Two paradigms have been applied for such, so far unsuccessful, attempts: a “native cellulolytic strategies”, aimed at conferring high-value product properties to natural cellulolytic microorganisms; b “recombinant cellulolytic strategies”, aimed to confer cellulolytic ability to microorganisms exhibiting high product yields and titers.By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

Ice Recrystallization Inhibiting Polymers Enable Glycerol-Free Cryopreservation of Micro-organisms.

Science.gov (United States)

Hasan, Muhammad; Fayter, Alice E R; Gibson, Matthew I

2018-06-22

All modern molecular biology and microbiology is underpinned not only by the tools to handle and manipulate microorganisms, but also those to store, bank and transport them. Glycerol is the current gold-standard cryoprotectant but it is intrinsically toxic to most micro-organisms: only a fraction of cells survive freezing and the presence of glycerol can impact down-stream applications and assays. Extremophile organisms survive repeated freeze/thaw cycles by producing antifreeze proteins which are potent ice recrystallization inhibitors. Here we introduce a new concept for the storage/transport of micro-organisms by using ice recrystallization inhibiting poly(vinyl alcohol) in tandem with poly(ethylene glycol). This cryopreserving formulation is shown to result in a 4-fold increase in E. coli yield post-thaw, compared to glycerol, utilizing lower concentrations, with successful cryopreservation at just 1.1 weight percent of additive. The mechanism of protection is demonstrated to be linked to inhibiting ice recrystallization (by comparison to a recombinant antifreeze protein) but also to the significantly lower toxicity of the polymers compared to glycerol. Optimized formulations are presented and shown to be broadly applicable to the cryopreservation of a panel of Gram negative, Gram positive and Mycobacteria strains. This represents a step-change in how micro-organisms will be stored by the design of new macromolecular ice growth inhibitors; it should enable a transition from traditional solvent-based to macromolecular microbiology storage methods.

Decomposition of diesel oil by various microorganisms

Energy Technology Data Exchange (ETDEWEB)

Suess, A; Netzsch-Lehner, A

1969-01-01

Previous experiments demonstrated the decomposition of diesel oil in different soils. In this experiment the decomposition of /sup 14/C-n-Hexadecane labelled diesel oil by special microorganisms was studied. The results were as follows: (1) In the experimental soils the microorganisms Mycoccus ruber, Mycobacterium luteum and Trichoderma hamatum are responsible for the diesel oil decomposition. (2) By adding microorganisms to the soil an increase of the decomposition rate was found only in the beginning of the experiments. (3) Maximum decomposition of diesel oil was reached 2-3 weeks after incubation.

Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

Science.gov (United States)

Liu, Juan; Jung, Jee H; Liu, Yonghong

2016-01-01

It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

Transformation of the insecticide teflubenzuron by microorganisms

NARCIS (Netherlands)

Finkelstein, Z.I.; Baskunov, B.P.; Rietjens, I.M.C.M.; Boersma, M.G.; Vervoort, J.; Golovleva, L.A.

2001-01-01

Transformation of teflubenzuron, the active component in the insecticide commercialized as Nomolt, by soil microorganisms was studied. It was shown that microorganisms, belonging to Bacillus, Alcaligenes, Pseudomonas and Acinetobacter genera are capable to perform the hydrolytic cleavage of the

Theory-generating practice. Proposing a principle for learning design

DEFF Research Database (Denmark)

Buhl, Mie

2016-01-01

This contribution proposes a principle for learning design – Theory-Generating Practice (TGP) – as an alternative to the way university courses are traditionally taught and structured, with a series of theoretical lectures isolated from practical experience and concluding with an exam or a project...... building, and takes tacit knowledge into account. The article introduces TGP, contextualizes it to a Danish tradition of didactics, and discusses it in relation to contemporary conceptual currents of didactic design and learning design. This is followed by a theoretical framing of TGP. Finally, three...

Integrating Health Behavior Theory and Design Elements in Serious Games.

Science.gov (United States)

Cheek, Colleen; Fleming, Theresa; Lucassen, Mathijs Fg; Bridgman, Heather; Stasiak, Karolina; Shepherd, Matthew; Orpin, Peter

2015-01-01

Internet interventions for improving health and well-being have the potential to reach many people and fill gaps in service provision. Serious gaming interfaces provide opportunities to optimize user adherence and impact. Health interventions based in theory and evidence and tailored to psychological constructs have been found to be more effective to promote behavior change. Defining the design elements which engage users and help them to meet their goals can contribute to better informed serious games. To elucidate design elements important in SPARX, a serious game for adolescents with depression, from a user-centered perspective. We proposed a model based on an established theory of health behavior change and practical features of serious game design to organize ideas and rationale. We analyzed data from 5 studies comprising a total of 22 focus groups and 66 semistructured interviews conducted with youth and families in New Zealand and Australia who had viewed or used SPARX. User perceptions of the game were applied to this framework. A coherent framework was established using the three constructs of self-determination theory (SDT), autonomy, competence, and relatedness, to organize user perceptions and design elements within four areas important in design: computer game, accessibility, working alliance, and learning in immersion. User perceptions mapped well to the framework, which may assist developers in understanding the context of user needs. By mapping these elements against the constructs of SDT, we were able to propose a sound theoretical base for the model. This study's method allowed for the articulation of design elements in a serious game from a user-centered perspective within a coherent overarching framework. The framework can be used to deliberately incorporate serious game design elements that support a user's sense of autonomy, competence, and relatedness, key constructs which have been found to mediate motivation at all stages of the change

INSTRUCTIONAL SYSTEMS DESIGN (ISD: Theory and Practice in Second Life

Directory of Open Access Journals (Sweden)

Nil GOKSEL CANBEK

2011-08-01

Full Text Available The considerable changes in distance learning related technologies and Web 2.0 tools direct new immersive platforms to serve on the concept of avatar-driven interactions. In this sense, the immersive learning platforms, like Second Life (SL, embrace innovative forms of network based settings for effective community interactions. SL, as an interactive learning milieu, conducts 3D interactions and active education within the context of Instructional Systems Design (ISD which makes learning experiences efficient for both the tutor and learners on the platform designed on social networking. The platform gives an appropriate service to its users to be part of an instructional application of virtual worlds in where learners become connected though online activities. Within the learning theories existing nowadays, instructional designers, who are working in 3D environment like SL, are using mainly cognitive theory and constructivist strategy of learning. According to cognitive learning theory, people learn in different ways that are individually contextual and new trends in Instructional Design (ID had to address these differences. There are number of already approbated instructional models, which are used widely in the process of creation learning courses for 3D environments. The most frequently used model is ADDIE (Assess–Design–Develop–Implement– Evaluate, and the model PIE (Plan-Integrate–Evaluate, that is relatively new and become increasingly popular as it allows easy integration of technology in the classroom-oriented (virtual or real teaching. Based on the above mentioned concerns, this paper will examine the instructional design models used to create immersive courses within SL. Further, the paper will collect ideas on the instructional tools and technologies used for designing SL courses as these new technologies used in this environment draws heavily on andragogy. The paper will also clarify the obstacles on virtual learning

The mathematical theory of signal processing and compression-designs

Science.gov (United States)

Feria, Erlan H.

2006-05-01

The mathematical theory of signal processing, named processor coding, will be shown to inherently arise as the computational time dual of Shannon's mathematical theory of communication which is also known as source coding. Source coding is concerned with signal source memory space compression while processor coding deals with signal processor computational time compression. Their combination is named compression-designs and referred as Conde in short. A compelling and pedagogically appealing diagram will be discussed highlighting Conde's remarkable successful application to real-world knowledge-aided (KA) airborne moving target indicator (AMTI) radar.

Role of passive body dynamics in micro-organism swimming in complex fluids

Science.gov (United States)

Thomases, Becca; Guy, Robert

2016-11-01

We investigate the role of passive body dynamics in the kinematics of swimming micro-organisms in complex fluids. Asymptotic analysis and linear theory are used to predict shape changes that result as body elasticity and fluid elasticity are varied. The analysis is compared with a computational model of a finite length swimmer in a Stokes-Oldroyd-B fluid. Simulations and theory agree quantitatively for small amplitude motions with low fluid elasticity (Deborah number). This may not be surprising as the theory is expected hold in these two regimes. What is more remarkable is that the predicted shape changes match the computational shape changes quantitatively for large amplitudes, even for large Deborah numbers. Shape changes only tell part of the story. Swimming speed depends on other effects as well. We see that shape changes can predict swimming speed well when either the amplitude is small (including large Deborah number) or when the Deborah number is small (including large amplitudes). It is only in the large De AND large amplitude regime where the theory breaks down and swimming speed can no longer be inferred from shape changes alone.

Product-oriented design theory for digital information services: A literature review.

NARCIS (Netherlands)

Wijnhoven, Alphonsus B.J.M.; Kraaijenbrink, Jeroen

2008-01-01

Purpose – The purpose of this paper is to give a structured literature review, design concepts, and research propositions related to a product-oriented design theory for information services. Information services facilitate the exchange of information goods with or without transforming these goods.

Modelling and application of the inactivation of microorganism

International Nuclear Information System (INIS)

Oğuzhan, P.; Yangılar, F.

2013-01-01

Prevention of consuming contaminated food with toxic microorganisms causing infections and consideration of food protection and new microbial inactivation methods are obligatory situations. Food microbiology is mainly related with unwanted microorganisms spoiling foods during processing and transporting stages and causing diseases. Determination of pathogen microorganisms is important for human health to define and prevent dangers and elongate shelf life. Inactivation of pathogen microorganisms can provide food security and reduce nutrient losses. Microbial inactivation which is using methods of food protection such as food safety and fresh. With this aim, various methods are used such as classical thermal processes (pasteurisation, sterilisation), pressured electrical field (PEF), ionised radiation, high pressure, ultrasonic waves and plasma sterilisation. Microbial inactivation modelling is a secure and effective method in food production. A new microbiological application can give useful results for risk assessment in food, inactivation of microorganisms and improvement of shelf life. Application and control methods should be developed and supported by scientific research and industrial applications

Artifical Microorganism Infection in Aviation Kerosene

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Dušan Vallo

2004-12-01

Full Text Available The fuel used in the aviation engineering has to be clean and dry, it may not contain mechanical impurities and water. Water inaviation kerosene may occur in soluble and insoluble form. The danger inheres in the insoluble form, which may drop out in the crystallineform and cause various failures, such as those caused by mechanical impurities. The water assists in the biological matter formation createdby various species of microorganisms (bacteria, mould fungi and yeast. The microorganisms, present in water phase occurring on thebottom of tanks or on the interface water phase – kerosene, grow and reproduce and subsequently may pollute (impair the fuel by thebiomass or by the products of their metabolism. There is a possibility to infect the fuel artificially by a selected reference microorganismstrain, which usually occur in contaminated fuel, or by microorganisms which cause a biological contamination of aviation kerosene.Out of the selected reference strains used in the experiments, the reference strains of Proteus vulgaris, Sacharamyces cerevisiae andClostridium perfringens were not cultivated in the sterile aviation kerosene and the propagating nutrient medium. The aviation kerosene actsas a biocide medium for the presented reference microorganism strains.

Behavior Space Design and Expression by the Theories and Methods of Urban Design—The Yan Dao ancient town of design practice

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Chen Wei

2015-01-01

Full Text Available In recent years, the ancient town of update and development has become a new hot spot, the study of old town renewal of concern is gradually warming. And again there are a lot of space in the middle of the old town renewal design and traditional style, space activities and use the contradiction between population, which becomes a problem urgently to be solved in design stage. The purpose of this study was to explore old town design space and behavior, traditional and modern conflict resolution methods, and to present the town development and design with a design concept. This paper’ uses three theories of urban design (The relationship between figure and ground, Contact theory and Place theory as a real-time monitoring, assessment, comparison of methods, to study Yan Dao Ancient Town, and the space for analysis. In the research, this paper based on the design theory of the three major city as a starting point, detailedly describes the different types in a certain area of difference in the behavior and the properties of space, and the ancient town of Hubei Shennongjia forest region salt path planning and design practice, the ancient town of updating the connotation of the historical context and space behavior of connection. The conclusion of this thesis put forward the method of that based on the space shape of ancient design method of its application in practice.

Generation of PHB from Spent Sulfite Liquor Using Halophilic Microorganisms.

Science.gov (United States)

Weissgram, Michaela; Gstöttner, Janina; Lorantfy, Bettina; Tenhaken, Raimund; Herwig, Christoph; Weber, Hedda K

2015-06-08

Halophilic microorganisms thrive at elevated concentrations of sodium chloride up to saturation and are capable of growing on a wide variety of carbon sources like various organic acids, hexose and also pentose sugars. Hence, the biotechnological application of these microorganisms can cover many aspects, such as the treatment of hypersaline waste streams of different origin. Due to the fact that the high osmotic pressure of hypersaline environments reduces the risk of contamination, the capacity for cost-effective non-sterile cultivation can make extreme halophilic microorganisms potentially valuable organisms for biotechnological applications. In this contribution, the stepwise use of screening approaches, employing design of experiment (DoE) on model media and subsequently using industrial waste as substrate have been implemented to investigate the applicability of halophiles to generate PHB from the industrial waste stream spent sulfite liquor (SSL). The production of PHB on model media as well as dilutions of industrial substrate in a complex medium has been screened for by fluorescence microscopy using Nile Blue staining. Screening was used to investigate the ability of halophilic microorganisms to withstand the inhibiting substances of the waste stream without negatively affecting PHB production. It could be shown that neither single inhibiting substances nor a mixture thereof inhibited growth in the investigated range, hence, leaving the question on the inhibiting mechanisms open. However, it could be demonstrated that some haloarchaea and halophilic bacteria are able to produce PHB when cultivated on 3.3% w/w dry matter spent sulfite liquor, whereas H. halophila was even able to thrive on 6.6% w/w dry matter spent sulfite liquor and still produce PHB.

Bioremediation of trinitrotolulene by a ruminal microorganism

Energy Technology Data Exchange (ETDEWEB)

Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

1995-10-01

2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

What Should Instructional Designers Know about General Systems Theory?

Science.gov (United States)

Salisbury, David F.

1989-01-01

Describes basic concepts in the field of general systems theory (GST) and explains the relationship between instructional systems design (ISD) and GST. Benefits of integrating GST into the curriculum of ISD graduate programs are discussed, and a short bibliography on GST is included. (LRW)

Plasma inactivation of food-related microorganisms in liquids

International Nuclear Information System (INIS)

Marsili, Lisa; Espie, Steven; Anderson, J.G.John G.; MacGregor, S.J.Scott J.

2002-01-01

This paper reports on a plasma process that inactivates microorganisms in liquids through the application of high-voltage pulses. These pulses result in breakdown of the gas and liquid layers, producing many active species such as UV photons, ozone, free radicals and free electrons. Several test microorganisms representing a range of problematic microorganisms were investigated. Significant reductions in microbial population were achieved, demonstrating the effectiveness of using the plasma discharge process to treat contaminated liquids

Metal-microorganism interactions

International Nuclear Information System (INIS)

Andres, Y.; Thouand, G.; Redercher, S.; Boualam, M.; Texier, A.Cl.; Hoeffer, R.

1997-01-01

The physico-chemical procedures of treating the metalliferous effluents are not always adapted to de polluting the slightly concentrated industrial wastes. An alternative idea was advanced, implying the ability of some microorganisms to fix in considerable amounts the metal ions present in aqueous solutions, possibly in a selective way. This approach has been investigated thoroughly during the last 30 years, particularly from a mechanistic point of view. The advantage of the microorganisms lies mainly in the large diversity of bacteria and in their chemical state dependent interaction with metals, as well as, in the possibilities of developing their selective and quantitative separation properties. A biomass from Mycobacterium smegmatis, an acidic alcoholic resistant bacteria, has been used to prepare a bio-sorption support allowing the preferential sorption of thorium as compared to uranium and lanthanum. These studies have been extended to biological polymers such as chitosan and to studies related to bioaccumulation mechanisms and/or to the microbial resistances towards metals

Esterase screening using whole cells of Brazilian soil microorganisms

Energy Technology Data Exchange (ETDEWEB)

Mantovani, Simone M.; Oliveira, Luciana G. de; Marsaioli, Anita J., E-mail: anita@iqm.unicamp.b [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

2010-07-01

A miniaturized enzymatic assay using fluorescent probes to reveal esterase producing microorganisms was optimized and applied to screen 64 soil bacterial strains. The best results were validated using traditional non-fluorogenic assays with acetyl and propanoyl phenylethanol to confirm the miniaturized results. The most active microorganisms belong to the genus Bacillus showing esterase activity and good enantiomeric ratios for the resolution of phenylethanol derivatives (E > 30). Part of the microorganisms are kept in our laboratory in glycerol or freezedried and the best microorganisms will be deposited in the CBMAI/CPQBA/UNICAMP culture collection. (author)

Pathogenic and opportunistic microorganisms in caves

Directory of Open Access Journals (Sweden)

Sanchez-Moral Sergio

2010-01-01

Full Text Available With today’s leisure tourism, the frequency of visits to many caves makes it necessary to know about possible potentially pathogenic microorganisms in caves, determine their reservoirs, and inform the public about the consequences of such visits. Our data reveal that caves could be a potential danger to visitors because of the presence of opportunistic microorganisms, whose existence and possible development in humans is currently unknown.

PROBIOTICS BASED ON TRANSGENIC MICROORGANISMS

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S. А. Starovoitova

2012-02-01

Full Text Available Modern tendencies of recombinant microorganisms creation for obtaining on their basis a new effective biopreparations (probiotics with wider spectrum of biological and therapeutic properties were considered. A lot of attention was focused on the main genera of perspective bacteria for creation of recombinant probiotics particularly: Lactococcus, Bifidobac terium,Bacillus, Escherichia. The main created Ukrainian and foreign gene-modified strains, that are widely used today in creation of effective recombinant biopreparations were characterized. Some fundamental directions and methods of gene-modified strains obtaining, which are used in getting effective biopreparations that used for therapy and prophylactic illness were reported, under which this group of pharmaceutical drugs were not used earlier. The safety matters of probiotics using on basis of genemodified strains were examined. Medical and veterinary biopreparations on basis of recombinant microorganisms could be used directly and effectively for therapy and prophylaxis of different illness, beginning from disbacteriosis up to cardiovascular diseases. It is related with some probiotic microorganisms ability for lowering of serum cholesterol at the host organism.

Secondary metabolites from marine microorganisms.

Science.gov (United States)

Kelecom, Alphonse

2002-03-01

After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

Secondary metabolites from marine microorganisms

Directory of Open Access Journals (Sweden)

KELECOM ALPHONSE

2002-01-01

Full Text Available After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

Microorganisms as sources of oils

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Thevenieau France

2013-11-01

Full Text Available A number of microorganism belonging to the genera of yeast, fungi, bacteria and microalgae have ability to accumulate substantial amounts of oil, sometimes up to an even in excess of 70% of their biomass weight under specific cultivation conditions. For nearly 100 years, the commercial opportunities of using microorganisms as sources of oils have been continuously examined. Although it was evident that microbial oils could never compete commercially with the major commodity plant oils, there were commercially opportunities for the production of some of the higher valued oils. Today, with the great progress of metabolic and genetic engineering, the developments are focus on the high value oils containing important polyunsaturated or specific fatty acids. Such oils have the potential to be used in different applications area as food, feed and oleochemistry. This review is covering the related researches about different oleaginous microorganisms for lipids production and microbial oils biosynthesis process. In add, the lipid metabolism, metabolic engineering strategies to increase lipid production and the economics of microbial oils production are introduced.

Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications.

Science.gov (United States)

Gudiña, Eduardo J; Teixeira, José A; Rodrigues, Lígia R

2016-02-18

Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens), and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics) constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications

Directory of Open Access Journals (Sweden)

Eduardo J. Gudiña

2016-02-01

Full Text Available Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens, and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

Microorganisms and methods for producing pyruvate, ethanol, and other compounds

Energy Technology Data Exchange (ETDEWEB)

Reed, Jennifer L.; Zhang, Xiaolin

2017-12-26

Microorganisms comprising modifications for producing pyruvate, ethanol, and other compounds. The microorganisms comprise modifications that reduce or ablate activity of one or more of pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase, phosphate acetyltransferase, acetate kinase, pyruvate oxidase, lactate dehydrogenase, cytochrome terminal oxidase, succinate dehydrogenase, 6-phosphogluconate dehydrogenase, glutamate dehydrogenase, pyruvate formate lyase, pyruvate formate lyase activating enzyme, and isocitrate lyase. The microorganisms optionally comprise modifications that enhance expression or activity of pyruvate decarboxylase and alcohol dehydrogenase. The microorganisms are optionally evolved in defined media to enhance specific production of one or more compounds. Methods of producing compounds with the microorganisms are provided.

[DIFFERENTIAL SENSITIVITY OF MICROORGANISMS TO POLYHEXAMETHYLENEGUANIDINE].

Science.gov (United States)

Lysytsya, A V; Mandygra, Y M; Bojko, O P; Romanishyna, O O; Mandygra, M S

2015-01-01

Factors identified that affect the sensitivity of microorganisms to polyhexamethyleneguanidine (PHMG). Salts of PHMG chloride, valerate, maleate, succinate was to use. Test strains of Esherichia coli, Staphylococcus aureus, Bacillus cereus, Leptospira interrogans, Paenibacillus larvae, Mycobacterium bovis, M. avium, M. fortuitum, Aspergillus niger and some strains of viruses are taken as objects of research. We have determined that the cytoplasm membrane phospholipids is main "target" for the polycation molecules of PHMG. A differential sensitivity of the microorganisms to this drug is primarily determined by relative amount of lipids in membrane and their accessibility. Such trends exist: increase the relative contents of anionic lipids and more negative surface electric potential of membrane, and reduction of the sizes fat acid remainder of lipids bring to increase of microorganism sensitivity. Types of anion salt PHMG just have a certain value. Biocide activity of PHMG chloride is more, than its salts with organic acid. Feasibility of combining PHMG with other biocides in the multicomponent disinfectants studied and analyzed. This combination does not lead to a significant increase in the sensitivity of microorganisms tested in most cases. Most species of pathogenic bacteria can be quickly neutralized by aqueous solutions of PHMG in less than 1% concentrations.

Mapping Cultural Frame Shifting in Interaction Design with Blending Theory

DEFF Research Database (Denmark)

Markussen, Thomas; Krogh, Peter Gall

2008-01-01

In this paper, we introduce Gilles Fauconnier & Mark Turner's blending theory as a new conceptual framework for explaining ‘cultural frame shifting' in interaction design. Cultural frame shifting is when people, through their explorative use of technology, are required imaginatively to reorganize...... their cultural background knowledge and expectations. In current HCI research it has occasionally been pointed out that a proper understanding of this phenomenon hinges on addressing the relationship between embodied interaction and cultural meaning construction as part of a larger interactive system. However...... the network model of mental spaces from Fauconnier & Turner's blending theory onto video material and interviews from initial qualitative use studies of a design case. In so doing we explore and argue for how meaning formation and embodied cognition coalesce in cultural frame shifting and provide a tool...

Microorganisms of Grape Berries

Directory of Open Access Journals (Sweden)

Kántor Attila

2017-12-01

Full Text Available Grape surface is an unstable habitat that changes greatly according to the stage of grape ripening. Different bacteria and yeasts can colonise the surface of grape berry and the diversity of microorganisms depends on the stage of ripening, pesticide application and health condition. The aim of this study was to study the microflora of the surface of grape berries. Altogether, 19 grape samples from Slovakia were collected. The spread plate method was applied and a 100 μL inoculum of each dilution (10−2, 10−3 was plated on TSA, MEA, and MRS agar for isolation of microorganisms from grapes. Proteins were extracted from cells by ethanol/formic acid extraction procedure. MALDI-TOF Mass Spectrometry was used for identification of microorganisms. In total, 11 genera of Gram-negative bacteria, 11 of Gram-positive bacteria and nine of yeasts were identified. Among 200 isolates, Gram-negative, Gram-positive bacteria and yeasts represented 11%, 27% and 62% of the total number of isolates studied. The most common genera of isolated yeasts were Hanseniaspora (37%, Metschnikowia (31%, and Rhodotorula (10%. The most frequently isolated among Gram-negative bacteria were Acinetobacter (22%, Pseudomonas (22% and Sphingomonas (13%. The most common genera of Gram-positive bacteria were Bacillus (20%, Lactobacillus (19%, Leuconostoc and Staphylococcus (11%, respectively.

Establishing Drug Resistance in Microorganisms by Mass Spectrometry

Science.gov (United States)

Demirev, Plamen A.; Hagan, Nathan S.; Antoine, Miquel D.; Lin, Jeffrey S.; Feldman, Andrew B.

2013-08-01

A rapid method to determine drug resistance in bacteria based on mass spectrometry is presented. In it, a mass spectrum of an intact microorganism grown in drug-containing stable isotope-labeled media is compared with a mass spectrum of the intact microorganism grown in non-labeled media without the drug present. Drug resistance is determined by predicting characteristic mass shifts of one or more microorganism biomarkers using bioinformatics algorithms. Observing such characteristic mass shifts indicates that the microorganism is viable even in the presence of the drug, thus incorporating the isotopic label into characteristic biomarker molecules. The performance of the method is illustrated on the example of intact E. coli, grown in control (unlabeled) and 13C-labeled media, and analyzed by MALDI TOF MS. Algorithms for data analysis are presented as well.

The CAL: cognitive, apperceptive and representative aspects of fashion design - Side note to neuroaesthetic theory

Science.gov (United States)

Csanák, Edit

2017-10-01

This article deals with the creative and cognitive process of the creative work from the aspect of fashion design. It is examined through the Cognitive-Apperceptive-Limn process (The CAL), analysing the stages of design work referring to prominent literature, and discussing exciting theories, such the FLOW and the AHA effects are, and the neuro aesthetic theory. Setting them into a new context, the article offers a fresh approach of a designer, rather than a scientific statement based on pragmatic findings. Since theories on artistic performance and creativity can never be enough ‘empirical’, and the process can be never understood enough well…

Role of Theories in the Design of Web-Based Person-Centered Support: A Critical Analysis

Directory of Open Access Journals (Sweden)

Agneta Ranerup

2014-01-01

Full Text Available Objective. The aim of this study was to provide a critical understanding of the role of theories and their compatibility with a person-centered approach in the design and evaluation of web-based support for the management of chronic illness. Methods. Exploration of web-based support research projects focusing on four cases: (1 preschool children aged 4–6 with bladder dysfunction and urogenital malformation; (2 young adults aged 16–25 living with mental illness; (3 women with type 1 diabetes who are pregnant or in early motherhood; and (4 women who have undergone surgery for breast cancer. Data comprised interviews with research leaders and documented plans. Analysis was performed by means of a cross-case methodology. Results. The used theories concerned design, learning, health and well-being, or transition. All web support products had been developed using a participatory design (PD. Fundamental to the technology design and evaluation of outcomes were theories focusing on learning and on health and well-being. All theories were compatible with a person-centered approach. However, a notable exception was the relatively collective character of PD and Communities of Practice. Conclusion. Our results illustrate multifaceted ways for theories to be used in the design and evaluation of web-based support.

The Modified Delphi Method to Analyze the Application of Instructional Design Theory to Online Graduate Education

Science.gov (United States)

Zeedick, Danielle Marie

2010-01-01

During the past several decades, the field of instructional design theory has experienced changes in what is mostly applied to traditional, on-ground education. While instructional design theory has been (and still is being) discussed, constructed, and deconstructed, there has been no agreement among prominent instructional design theory…

Use of the Halbach perturbation theory for the multipole design of the ALS storage ring sextupole

Energy Technology Data Exchange (ETDEWEB)

Marks, S. [Lawrence Berkeley Lab., CA (United States)

1995-02-01

The Advanced Light Source (ALS) storage ring sextupole is a unique multi-purpose magnet. It is designed to operate in the primary or sextupole mode and in three auxiliary trim modes: horizontal steering, vertical steering, and skew quadrupole. Klaus Halbach developed a perturbation theory for iron-dominated magnets which provides the basis for this design. Many magnet designers, certainly those who have been exposed to Klaus, are familiar with this theory and have used it for such things as evaluating the effect of assembly alignment errors. The ALS sextupole design process was somewhat novel in its use of the perturbation theory to design essential features of the magnet. In particular, the steering and skew quadrupole functions are produced by violating sextupole symmetry and are thus perturbations of the normal sextupole excitation. The magnet was designed such that all four modes are decoupled and can be excited independently. This paper discusses the use of Halbach`s perturbation theory to design the trim functions and to evaluate the primary asymmetry in the sextupole mode, namely, a gap in the return yoke to accommodate the vacuum chamber. Prototype testing verified all operating modes of the magnet and confirmed the expected performance from calculations based upon the Halbach perturbation theory. A total of 48 sextupole magnets of this design are now installed and operating successfully in the ALS storage ring.

Antimicrobial Effects of Garcinia Mangostana on Cariogenic Microorganisms.

Science.gov (United States)

Janardhanan, Sunitha; Mahendra, Jaideep; Girija, A S Smiline; Mahendra, Little; Priyadharsini, Vijayashree

2017-01-01

Garcinia mangostana commonly called as Mangosteen fruit has been used as an antibacterial agent since age old times. The mangosteen pericarp has proven to have antibacterial effect, but the effect of the same on cariogenic organisms has not been explored. The present study was an attempt to gain a better understanding of the antibacterial effect of mangosteen pericarp on the cariogenic bacteria, to unravel the therapeutic potential for the same. The aim of the study was to assess the antibacterial efficacy of the crude chloroform extract of mangosteen pericarp against cariogenic bacteria. The study was done under laboratory settings using an in vitro design. The microorganisms namely Streptococcus mutans, Streptococcus sanguis, Streptococcus salivarius, Streptococcus oralis and Lactobacillus acidophilus were procured from American Type Cell Culture (ATCC) and Microbial Type Culture Collection (MTCC) were revived and lawn cultured. The antibacterial effect of mangosteen pericarp was tested using agar well diffusion method on Trypticase Soy Agar-Blood Agar (TSA-BA) and de Man, Rogosa and Sharpe (MRS) agar media. The standard antiplaque agent chlorhexidine was used as the positive control. This cross-sectional, experimental study was done in Central Research laboratory, Meenakshi Ammal Dental College for period of eight weeks. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values were determined by microbroth dilution method. Statistical analysis was done by calculating the mean of the zones of inhibition on tested microorganisms. Mann-Whitney test was done to compare the zones of inhibition of mangosteen and chlorhexidine. The antibacterial bioassay showed the highest activity for Lactobacillus acidophilus (13.6 mm) and Streptococcus sanguis (13.6 mm), whereas, it showed a medium and low activity for Streptococcus oralis (11.3 mm), Streptococcus mutans (10.6 mm) and Streptococcus salivarius (3 mm) respectively. The MBC and MIC

Improved Method for Direct Detection of Environmental Microorganisms Using an Amplification of 16S rDNA Region

Science.gov (United States)

Tsujimura, M.; Akutsu, J.; Zhang, Z.; Sasaki, M.; Tajima, H.; Kawarabayasi, Y.

2004-12-01

The thermostable proteins or enzymes were expected to be capable to be utilized in many areas of industries. Many thermophilic microorganisms, which possess the thermostable proteins or enzymes, were identified from the extreme environment. However, many unidentified and uncultivable microorganisms are still remaining in the environment on the earth. It is generally said that the cultivable microorganisms are less than 1% of entire microorganisms living in the earth, remaining over 99% are still uncultivable. As an approach to the uncultivable microorganisms, the PCR amplification of 16S rDNA region using primer sets designed from the conserved region has been generally utilized for detection and community analysis of microorganism in the environment. However, the facts, that PCR amplification introduces the mutation in the amplified DNA fragment and efficiency of PCR amplification is depend on the sequences of primer sets, indicated that the improving of PCR analysis was necessary for more correct detection of microorganisms. As the result of evaluation for the quality of DNA polymerases, sequences of primers used for amplification and conditions of PCR amplification, the DNA polymerase, the primer set and the conditions for amplification, which did not amplify the DNA fragment from the DNA contaminated within the DNA polymerase itself, were successfully selected. Also the rate of mutation in the DNA fragment amplified was evaluated using this conditions and the genomic DNA from cultivable microbes as a template. The result indicated the rate of mutation introduced by PCR was approximately 0.1% to 0.125%. The improved method using these conditions and error rate calculated was applied for the analysis of microorganisms in the geothermal environment. The result indicated that four kinds of dominant microorganisms, including both of bacteria and archaea, were alive within soil in the hot spring in Tohoku Area. We would like to apply this improved method to detection

The use of network theory to model disparate ship design information

Science.gov (United States)

Rigterink, Douglas; Piks, Rebecca; Singer, David J.

2014-06-01

This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship's distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

Biodiesel production by various oleaginous microorganisms from organic wastes.

Science.gov (United States)

Cho, Hyun Uk; Park, Jong Moon

2018-05-01

Biodiesel is a biodegradable and renewable fuel. A large amount of research has considered microbial oil production using oleaginous microorganisms, but the commercialization of microbial lipids produced in this way remains uncertain due to the high cost of feedstock or low lipid yield. Microbial lipids can be typically produced by microalgae, yeasts, and bacteria; the lipid yields of these microorganisms can be improved by using sufficient concentrations of organic carbon sources. Therefore, combining low-cost organic compounds contained in organic wastes with cultivation of oleaginous microorganisms can be a promising approach to obtain commercial viability. However, to achieve effective bioconversion of low-cost substrates to microbial lipids, the characteristics of each microorganism and each substrate should be considered simultaneously. This article discusses recent approaches to developing cost-effective microbial lipid production processes that use various oleaginous microorganisms and organic wastes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Glyphosate-Degrading Microorganisms from Industrial Activated Sludge

OpenAIRE

Balthazor, Terry M.; Hallas, Laurence E.

1986-01-01

A plating medium was developed to isolate N-phosphonomethylglycine (glyphosate)-degrading microorganisms, with glyphosate as the sole phosphorus source. Two industrial biosystems treating glyphosate wastes contained elevated microbial counts on the medium. One purified isolate metabolized glyphosate to aminomethylphosphonic acid, mineralizing this accumulating intermediate during log growth. This microorganism has been identified as a Flavobacterium species.

Bioremediation of Industrial Waste Through Enzyme Producing Marine Microorganisms.

Science.gov (United States)

Sivaperumal, P; Kamala, K; Rajaram, R

Bioremediation process using microorganisms is a kind of nature-friendly and cost-effective clean green technology. Recently, biodegradation of industrial wastes using enzymes from marine microorganisms has been reported worldwide. The prospectus research activity in remediation area would contribute toward the development of advanced bioprocess technology. To minimize industrial wastes, marine enzymes could constitute a novel alternative in terms of waste treatment. Nowadays, the evidence on the mechanisms of bioremediation-related enzymes from marine microorganisms has been extensively studied. This review also will provide information about enzymes from various marine microorganisms and their complexity in the biodegradation of comprehensive range of industrial wastes. © 2017 Elsevier Inc. All rights reserved.

Application of microorganism to in-situ leaching mining

International Nuclear Information System (INIS)

Yu, Runlan; Sato, Kazuhiko; Nagara, Shuichi; Yamana, Satoshi

1998-01-01

In-situ leaching (ISL) technique has come into the spotlight recently because of its low production costs and low environmental impact. In China, development and application of economical ISL techniques are also being studied. To design a pilot scale ISL 'bioreactor' in China, applicability of microorganisms to ISL mining was evaluated at Ningyo Toge Works as a part of Scientist Exchange Program of the Science and Technology Agency. An overview of the indirect bio-ISL method with iron oxidizing bacteria, Thiobacillus ferroxidans (TF), and results from experiment to determine factors for the ISL 'bioreactor' are discussed. (author)

SELECTION OF MICROORGANISMS FOR FERMENTATION OF MEAT MATERIALS

Directory of Open Access Journals (Sweden)

Danylenko S. G.

2014-08-01

Full Text Available Principal criteria for the selection of microorganisms with a wide range of biological and technological properties for fermentation of raw meats are considered. Attention is paid to the main groups of microorganisms such as Micrococсus, Staphylococcus, Lactobacillus, Bifidobacterium and Propionibacterium which are promising for creation of bacterial preparations. To create bacterial preparations, the basic criteria of selection for microorganisms were determined as follows: the ability of microorganisms to be developed within the specific ecological niche (raw meat materials and their influence on flavor characteristics of the final product under the conditions of intensification of production technologies of meat products. Methods used for search and retrieval of technologically promising strains from different natural sources (fresh meats, minced meats, meat, dairy and sour-milk products, vegetables, fruit, brines and mixtures for salting are considered.

Application of thermotolerant microorganisms for biofertilizer preparation.

Science.gov (United States)

Chen, Kuo-Shu; Lin, Yann-Shying; Yang, Shang-Shyng

2007-12-01

Intensive agriculture is practised in Taiwan, and compost application is very popular as a means of improving the soil physical properties and supplying plant nutrition. We tested the potential of inoculation with thermotolerant microorganisms to shorten the maturity and improve the quality of biofertilizer prepared by composting. Thermotolerant microorganisms were isolated from compost and reinoculated for the preparation of biofertilizer. The physical, chemical and biological properties of the biofertilizer were determined during composting. The effects of biofertilizer application on the growth and yield of rape were also studied. Among 3823 colonies of thermotolerant microorganisms, Streptomyces thermonitrificans NTU-88, Streptococcus sp. NTU-130 and Aspergillus fumigatus NTU-132 exhibited high growth rates and cellulolytic and proteolytic activities. When a mixture of rice straw and swine manure were inoculated with these isolates and composted for 61 days, substrate temperature increased initially and then decreased gradually during composting. Substrate pH increased from 7.3 to 8.5. Microbial inoculation enhanced the rate of maturity, and increased the content of ash and total and immobilized nitrogen, improved the germination rate of alfalfa seed, and decreased the content of total organic carbon and the carbon/nitrogen ratio. Biofertilizer application increased the growth and yield of rape. Inoculation of thermotolerant and thermophilic microorganisms to agricultural waste for biofertilizer preparation enhances the rate of maturity and improves the quality of the resulting biofertilizer. Inoculation of appropriate microorganisms in biofertilizer preparation might be usefully applied to agricultural situations.

Nitrogen acquisition by plants and microorganisms in a temperate grassland.

Science.gov (United States)

Liu, Qianyuan; Qiao, Na; Xu, Xingliang; Xin, Xiaoping; Han, Jessie Yc; Tian, Yuqiang; Ouyang, Hua; Kuzyakov, Yakov

2016-03-10

Nitrogen (N) limitation is common in most terrestrial ecosystems, often leading to strong competition between microorganisms and plants. The mechanisms of niche differentiation to reduce this competition remain unclear. Short-term (15)N experiments with NH4(+), NO3(-), and glycine were conducted in July, August and September in a temperate grassland to evaluate the chemical, spatial and temporal niche differentiation by competition between plants and microorganisms for N. Microorganisms preferred NH4(+) and NO3(-), while plants preferred NO3(-). Both plants and microorganisms acquired more N in August and September than in July. The soil depth had no significant effects on microbial uptake, but significantly affected plant N uptake. Plants acquired 67% of their N from the 0-5 cm soil layer and 33% from the 5-15 cm layer. The amount of N taken up by microorganisms was at least seven times than plants. Although microorganisms efficiently compete for N with plants, the competition is alleviated through chemical partitioning mainly in deeper soil layer. In the upper soil layer, neither chemical nor temporal niche separation is realized leading to strong competition between plants and microorganisms that modifies N dynamics in grasslands.

Mechanisms of nickel toxicity in microorganisms

OpenAIRE

Macomber, Lee; Hausinger, Robert P.

2011-01-01

Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological co...

Design and control of the precise tracking bed based on complex electromechanical design theory

Science.gov (United States)

Ren, Changzhi; Liu, Zhao; Wu, Liao; Chen, Ken

2010-05-01

The precise tracking technology is wide used in astronomical instruments, satellite tracking and aeronautic test bed. However, the precise ultra low speed tracking drive system is one high integrated electromechanical system, which one complexly electromechanical design method is adopted to improve the efficiency, reliability and quality of the system during the design and manufacture circle. The precise Tracking Bed is one ultra-exact, ultra-low speed, high precision and huge inertial instrument, which some kind of mechanism and environment of the ultra low speed is different from general technology. This paper explores the design process based on complex electromechanical optimizing design theory, one non-PID with a CMAC forward feedback control method is used in the servo system of the precise tracking bed and some simulation results are discussed.

Teaching Reform of Course Group Regarding Theory and Design of Mechanisms Based on MATLAB Technology

Science.gov (United States)

Shen, Yi; Yuan, Mingxin; Wang, Mingqiang

2013-01-01

Considering that the course group regarding theory and design of mechanisms is characterized by strong engineering application background and the students generally feel very boring and tedious during the learning process, some teaching reforms for the theory and design of mechanisms are carried out to improve the teaching effectiveness in this…

Enhancement of uranium-accumulating ability of microorganisms by irradiation

Energy Technology Data Exchange (ETDEWEB)

Sakaguchi, Takashi; Nakajima, Akira; Tsuruta, Takehiko [Miyazaki Medical Coll., Kiyotake (Japan)

1998-01-01

Some microorganisms having excellent ability to accumulate uranium were isolated, from soil and water systems in and around the Ningyo-toge Station of Power Reactor and Nuclear Fuel Development Corporation. The enhancement of uranium-accumulating ability of microorganisms by electron-beam irradiation was examined, and the ability of JW-046 was increased 3-5% by the irradiation. The irradiation affect the growth of some of microorganisms tested. (author)

the economic importance of microorganism in food processing

African Journals Online (AJOL)

BSN

This paper attempts to highlight the Economic Importance of microorganisms in food processing and manufacturing; it goes further to differentiate between the desirable ... Desirable importance are those cost saving and revenue generating activities ... Microorganism (yeast) play very useful role in the Bakery industries.

Spherical perturbations of hairy black holes in designer gravity theories

International Nuclear Information System (INIS)

Battarra, Lorenzo

2012-01-01

We study the spectrum of the scalar l = 0 quasi-normal frequencies of anti-de Sitter hairy black holes in four- and five-dimensional designer gravity theories of the Einstein-scalar type, arising as consistent truncations of N= 8 gauged supergravity. In the dual field theory, such hairy black holes represent thermal states in which the operator corresponding to the bulk scalar field is condensed, due to the multi-trace deformation associated with non-standard boundary conditions. We show that, in a particular class of models, the effective potential describing the vacua of the deformed dual theory can be identified, at large values of the condensate, with the deformation plus the conformal coupling of the condensate to the curvature of the boundary geometry. In this limit, we show that the least damped quasi-normal frequency of the corresponding hairy black holes can be accurately predicted by the curvature of the effective potential describing the field theory at finite entropy. (paper)

Synthetic biology expands chemical control of microorganisms.

Science.gov (United States)

Ford, Tyler J; Silver, Pamela A

2015-10-01

The tools of synthetic biology allow researchers to change the ways engineered organisms respond to chemical stimuli. Decades of basic biology research and new efforts in computational protein and RNA design have led to the development of small molecule sensors that can be used to alter organism function. These new functions leap beyond the natural propensities of the engineered organisms. They can range from simple fluorescence or growth reporting to pathogen killing, and can involve metabolic coordination among multiple cells or organisms. Herein, we discuss how synthetic biology alters microorganisms' responses to chemical stimuli resulting in the development of microbes as toxicity sensors, disease treatments, and chemical factories. Copyright © 2015 Elsevier Ltd. All rights reserved.

Numerically-based ducted propeller design using vortex lattice lifting line theory

OpenAIRE

Stubblefield, John M.

2008-01-01

CIVINS (Civilian Institutions) Thesis document This thesis used vortex lattice lifting line theory to model an axisymmetrical-ducted propeller with no gap between the duct and the propeller. The theory required to model the duct and its interaction with the propeller were discussed and implemented in Open-source Propeller Design and Analysis Program (OpenProp). Two routines for determining the optimum circulation distribution were considered, and a method based on calculus of variation...

Practical Applications of Generalizability Theory for Designing, Evaluating, and Improving Psychological Assessments.

Science.gov (United States)

Vispoel, Walter P; Morris, Carrie A; Kilinc, Murat

2018-01-01

In this article, we illustrate how generalizability theory (G-theory) can extend traditional assessment methods for designing, improving, and evaluating results from both objectively and subjectively scored measures of individual differences. Our illustrations include quantification of multiple sources of measurement error, derivation of unique indexes of consistency for norm- and criterion-referenced interpretations of scores, estimation of score consistency when changing a measurement procedure, and disattenuation of correlation coefficients for measurement error. We also expand G-theory analyses beyond the item level to include parcels and split measures and highlight linkages among G-theory, classical test theory, and structural equation modeling. Computer code and sample data are provided in online supplements to help readers apply the demonstrated techniques to their own assessments.

The use of network theory to model disparate ship design information

Directory of Open Access Journals (Sweden)

Douglas Rigterink

2014-06-01

Full Text Available This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship's distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

The use of network theory to model disparate ship design information

Directory of Open Access Journals (Sweden)

Rigterink Douglas

2014-06-01

Full Text Available This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship’s distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

Design of Mobile Augmented Reality in Health Care Education: A Theory-Driven Framework.

Science.gov (United States)

Zhu, Egui; Lilienthal, Anneliese; Shluzas, Lauren Aquino; Masiello, Italo; Zary, Nabil

2015-09-18

Augmented reality (AR) is increasingly used across a range of subject areas in health care education as health care settings partner to bridge the gap between knowledge and practice. As the first contact with patients, general practitioners (GPs) are important in the battle against a global health threat, the spread of antibiotic resistance. AR has potential as a practical tool for GPs to combine learning and practice in the rational use of antibiotics. This paper was driven by learning theory to develop a mobile augmented reality education (MARE) design framework. The primary goal of the framework is to guide the development of AR educational apps. This study focuses on (1) identifying suitable learning theories for guiding the design of AR education apps, (2) integrating learning outcomes and learning theories to support health care education through AR, and (3) applying the design framework in the context of improving GPs' rational use of antibiotics. The design framework was first constructed with the conceptual framework analysis method. Data were collected from multidisciplinary publications and reference materials and were analyzed with directed content analysis to identify key concepts and their relationships. Then the design framework was applied to a health care educational challenge. The proposed MARE framework consists of three hierarchical layers: the foundation, function, and outcome layers. Three learning theories-situated, experiential, and transformative learning-provide foundational support based on differing views of the relationships among learning, practice, and the environment. The function layer depends upon the learners' personal paradigms and indicates how health care learning could be achieved with MARE. The outcome layer analyzes different learning abilities, from knowledge to the practice level, to clarify learning objectives and expectations and to avoid teaching pitched at the wrong level. Suggestions for learning activities and the

Influence of microorganisms on the alteration of glasses

International Nuclear Information System (INIS)

Besnainou, B.; Libert, M.F.

1997-01-01

Under specific conditions, microorganisms may enhance the alteration process of basaltic glass. However bacterial activity in the near field of a glass container would be possible only in environmental conditions provide nutrients and energetic substrates for bacterial growth. Depending of these conditions, microorganisms can: - modify the pH or the medium, - consume or produce soluble organic acids. To qualify the long term behaviour of glass, in presence of microorganisms, a qualitative and quantitative estimation of microbial activity potentialities and their consequences is needed. This must be achieved in studying the availability of the chemical species in the environment. (authors)

[Relationships between air conditioning, airborne microorganisms and health].

Science.gov (United States)

Parat, S; Perdrix, A; Baconnier, P

1999-01-01

Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

Atmospheric Sampling of Microorganisms with UAS

Science.gov (United States)

Schmale, D. G., III

2017-12-01

Many microorganisms relevant to crops, domestic animals, and humans are transported over long distances through the atmosphere. Some of these atmospheric microbes catalyze the freezing of water at higher temperatures and facilitate the onset of precipitation. A few have crossed continents. New technologies are needed to study the movement of microorganisms in the atmosphere. We have used unmanned aircraft systems (UAS) to study the transport of microorganisms tens to hundreds of meters above the ground. These UAS are equipped with unique devices for collecting microbes in the atmosphere during flight. Autonomous systems enable teams of UAS to perform complex atmospheric sampling tasks, and coordinate flight missions with one another. Data collected with UAS can be used to validate and improve disease forecasting models along highways in the sky, connecting transport scales across farms, states, and continents. Though terrestrial environments are often considered a major contributor to atmospheric microbial aerosols, little is known about aquatic sources of microbial aerosols. Droplets containing microorganisms can aerosolize from the water surface, liberating them into the atmosphere. We are using teams of unmanned surface vehicles (USVs) and UAS to study the aerosolization of microbes from aquatic environments. Controlled flume studies using highspeed video have allowed us to observe unique aerosolization phenomena that can launch microbes out of the water and into the air. Unmanned systems may be used to excite the next generation of biologists and engineers, and raise important ethical considerations about the future of human-robot interactions.

[Ants as carriers of microorganisms in hospital environments].

Science.gov (United States)

Pereira, Rogério Dos Santos; Ueno, Mariko

2008-01-01

Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

Multiorganismal insects: diversity and function of resident microorganisms.

Science.gov (United States)

Douglas, Angela E

2015-01-07

All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests.

Cultivation of shear stress sensitive microorganisms in disposable bag reactor systems.

Science.gov (United States)

Jonczyk, Patrick; Takenberg, Meike; Hartwig, Steffen; Beutel, Sascha; Berger, Ralf G; Scheper, Thomas

2013-09-20

Technical scale (≥5l) cultivations of shear stress sensitive microorganisms are often difficult to perform, as common bioreactors are usually designed to maximize the oxygen input into the culture medium. This is achieved by mechanical stirrers, causing high shear stress. Examples for shear stress sensitive microorganisms, for which no specific cultivation systems exist, are many anaerobic bacteria and fungi, such as basidiomycetes. In this work a disposable bag bioreactor developed for cultivation of mammalian cells was investigated to evaluate its potential to cultivate shear stress sensitive anaerobic Eubacterium ramulus and shear stress sensitive basidiomycetes Flammulina velutipes and Pleurotus sapidus. All cultivations were compared with conventional stainless steel stirred tank reactors (STR) cultivations. Good growth of all investigated microorganisms cultivated in the bag reactor was found. E. ramulus showed growth rates of μ=0.56 h⁻¹ (bag) and μ=0.53 h⁻¹ (STR). Differences concerning morphology, enzymatic activities and growth in fungal cultivations were observed. In the bag reactor growth in form of small, independent pellets was observed while STR cultivations showed intense aggregation. F. velutipes reached higher biomass concentrations (21.2 g l⁻¹ DCW vs. 16.8 g l⁻¹ DCW) and up to 2-fold higher peptidolytic activities in comparison to cell cultivation in stirred tank reactors. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimal design of earth-moving machine elements with cusp catastrophe theory application

Science.gov (United States)

Pitukhin, A. V.; Skobtsov, I. G.

2017-10-01

This paper deals with the optimal design problem solution for the operator of an earth-moving machine with a roll-over protective structure (ROPS) in terms of the catastrophe theory. A brief description of the catastrophe theory is presented, the cusp catastrophe is considered, control parameters are viewed as Gaussian stochastic quantities in the first part of the paper. The statement of optimal design problem is given in the second part of the paper. It includes the choice of the objective function and independent design variables, establishment of system limits. The objective function is determined as mean total cost that includes initial cost and cost of failure according to the cusp catastrophe probability. Algorithm of random search method with an interval reduction subject to side and functional constraints is given in the last part of the paper. The way of optimal design problem solution can be applied to choose rational ROPS parameters, which will increase safety and reduce production and exploitation expenses.

Variation of microorganism concentrations in urban stormwater runoff with land use and seasons.

Science.gov (United States)

Selvakumar, Ariamalar; Borst, Michael

2006-03-01

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three different land use areas based on local designation (high-density residential, low-density residential and landscaped commercial). The concentrations of microorganisms in the stormwater runoff were found to be similar in magnitude to, but less variable than, those reported in the stormwater National Pollutant Discharge Elimination System (NPDES) database. Microorganism concentrations from high-density residential areas were higher than those associated with low-density residential and landscaped commercial areas. Since the outfalls were free of sanitary wastewater cross-connections, the major sources of microorganisms to the stormwater runoff were most likely from the feces of domestic animals and wildlife. Concentrations of microorganisms were significantly affected by the season during which the samples were collected. The lowest concentrations were observed during winter except for Staphylococcus aureus. The Pearson correlation coefficients among different indicators showed weak linear relationships and the relationships were statistically significant. However, the relationships between indicators and pathogens were poorly correlated and were not statistically significant, suggesting the use of indicators as evidence of the presence of pathogens is not appropriate. Further, the correlation between the concentration of the traditionally monitored indicators (total coliforms and fecal coliforms) and the suggested substitutes (enterococci and E. coli) is weak, but statistically significant, suggesting that historical time series will be only a qualitative indicator of impaired waters under the revised criteria for recreational water quality by the US EPA.

Food fermentations: Microorganisms with technological beneficial use

DEFF Research Database (Denmark)

Bourdichon, François; Casaregola, Serge; Farrokh, Choreh

2012-01-01

Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on “the history of use”, “traditional food”, or “general recognition of safety”. Authoritative lists of microorganism......, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature....... cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables...

Lateral gene exchanges shape the genomes of amoeba-resisting microorganisms

Directory of Open Access Journals (Sweden)

Claire eBertelli

2012-08-01

Full Text Available Based on Darwin’s concept of the tree of life, vertical inheritance was thought to be dominant, and mutations, deletions and duplication were streaming the genomes of living organisms. In the current genomic era, increasing data indicated that both vertical and lateral gene inheritance interact in space and time to trigger genome evolution, particularly among microorganisms sharing a given ecological niche. As a paradigm to their diversity and their survival in a variety of cell types, intracellular microorganisms, and notably intracellular bacteria, were considered as less prone to lateral genetic exchanges. Such specialized microorganisms generally have a smaller gene repertoire because they do rely on their host’s factors for some basic regulatory and metabolic functions. Here we review events of lateral gene transfer (LGT that illustrate the genetic exchanges among intra-amoebal microorganisms or between the microorganism and its amoebal host. We tentatively investigate the functions of laterally transferred genes in the light of the interaction with their host as they should confer a selective advantage and success to the amoeba-resisting microorganisms.

Producing Biosurfactants from Purified Microorganisms Obtained from Oil-contaminated Soil

Directory of Open Access Journals (Sweden)

Nader Mokhtarian

2010-09-01

Full Text Available Contamination of soil by crude oil can pose serious problems to ecosystems. Soil washing by solutions containing biosurfactants is one of the most efficient methods for the remediation of contaminated soil by crude oil because it removes not only the crude oil but also heavy metals. In this study, five soil samples were taken from fields exposed to oil compounds over the years in order to produce biosurfactants from microorganisms that were capable of degrading oil compounds. Sixteen such microorganisms were isolated. After cultivation, their emulsification strength was examined using E24 test. From among the experimental microorganisms, a gram-negative and rod-shape microorganism called A-12 showed the greatest value of the E24 test index (36%. For each liter of the culture medium containing 365 mg of microorganisms, 3 gr of the biosurfactant compound was produced and separated as dried powder. The purified biosurfactant was used in the soil washing process. Also, the insulated microorganisms were capable of degrading crude oil floating on wastewaters.

Synergistic interface behavior of strontium adsorption using mixed microorganisms.

Science.gov (United States)

Hu, Wenyuan; Dong, Faqin; Yang, Guangmin; Peng, Xin; Huang, Xiaojun; Liu, Mingxue; Zhang, Jing

2017-08-10

The proper handling of low-level radioactive waste is crucial to promote the sustainable development of nuclear power. Research into the mechanism for interactions between bacterium and radionuclides is the starting point for achieving successful remediation of radionuclides with microorganisms. Using Sr(II) as a simulation radionuclide and the mixed microorganisms of Saccharomyces cerevisiae and Bacillus subtilis as the biological adsorbent, this study investigates behavior at the interface between Sr(II) and the microorganisms as well as the mechanisms governing that behavior. The results show that the optimal ratio of mixed microorganisms is S. cerevisiae 2.0 g L -1 to B. subtilis 0.05 g L -1 , and the optimal pH is about 6.3. Sr(II) biosorption onto the mixed microorganisms is spontaneous and endothermic in nature. The kinetics and the equilibrium isotherm data of the biosorption process can be described with pseudo-second-order equation and the Langmuir isotherm equation, respectively. The key interaction between the biological adsorbent and Sr(II) involves shared electronic pairs arising from chemical reactions via bond complexation or electronic exchange, and spectral and energy spectrum analysis show that functional groups (e.g., hydroxyl, carboxyl, amino, amide) at the interface between the radionuclide and the mixed microorganisms are the main active sites of the interface reactions.

Low-voltage CMOS operational amplifiers theory, design and implementation

CERN Document Server

Sakurai, Satoshi

1995-01-01

Low-Voltage CMOS Operational Amplifiers: Theory, Design and Implementation discusses both single and two-stage architectures. Opamps with constant-gm input stage are designed and their excellent performance over the rail-to-rail input common mode range is demonstrated. The first set of CMOS constant-gm input stages was introduced by a group from Technische Universiteit, Delft and Universiteit Twente, the Netherlands. These earlier versions of circuits are discussed, along with new circuits developed at the Ohio State University. The design, fabrication (MOSIS Tiny Chips), and characterization of the new circuits are now complete. Basic analog integrated circuit design concepts should be understood in order to fully appreciate the work presented. However, the topics are presented in a logical order and the circuits are explained in great detail, so that Low-Voltage CMOS Operational Amplifiers can be read and enjoyed by those without much experience in analog circuit design. It is an invaluable reference boo...

Microorganisms associated with the spoilage of avocado pear ...

African Journals Online (AJOL)

The microorganisms associated with the spoilage of Avocado pear, Persea americana fruits, purchased fresh from various markets in Benin City were investigated. The pour plate method was used for the isolation. A total of nine species of microorganisms were isolated and identified in this study. They comprise of seven ...

Fundamentals of information theory and coding design

CERN Document Server

Togneri, Roberto

2003-01-01

In a clear, concise, and modular format, this book introduces the fundamental concepts and mathematics of information and coding theory. The authors emphasize how a code is designed and discuss the main properties and characteristics of different coding algorithms along with strategies for selecting the appropriate codes to meet specific requirements. They provide comprehensive coverage of source and channel coding, address arithmetic, BCH, and Reed-Solomon codes and explore some more advanced topics such as PPM compression and turbo codes. Worked examples and sets of basic and advanced exercises in each chapter reinforce the text's clear explanations of all concepts and methodologies.

Method and apparatus for detecting micro-organisms

International Nuclear Information System (INIS)

Mirsky, J.

1976-01-01

A method and apparatus is described for determining the presence and quantity of microorganisms, such as bacteria, fungi and yeast, in a given sample. The apparatus includes two sealed containers, a portion of which may be penetrated by a sharp instrument, as for example, glass vials with flexible septum tops. One container includes a radioactive nutrient medium which is capable of supporting the life process of the microorganism whose presence is being tested. The second container includes a liquid scintillation solution which absorbs the product of metabolism of the organisms. The sample is introduced into the first sealed container, for example, by means of a standard syringe. Any microorganisms present will consume the radioactive nutrient and as a result produce radioactive waste. Means are then applied to penetrate the containers and allow the flow of the radioactive metabolic product from the first container to the second container while preventing any contamination from the ambient. The liquid scintillation solution will emit light in proportion to the amount of the product of metabolism collected from the first container. This light may be detected by standard liquid scintillation counters, thus providing a qualitative and quantitative measure of the microorganism in the tested sample

Pesticides in Soil: Effects on Microorganisms

Directory of Open Access Journals (Sweden)

Ljiljana Radivojević

2007-01-01

Full Text Available Since their discovery to the present day, pesticides have been an inevitable segment of agricultural production and efforts have been made to synthesize compounds that would share a required efficacy along with selectivity, sufficient persistence on the object of protection and favourable toxicological and ecotoxicological characteristics so as to minimize their effect on the environment.When a pesticide gets into soil after application, it takes part in a number of physical, chemical and biological processes that depend not only on the compound itself, but a number of other factors as well, such as: physical, chemical and biological characteristics of soil; climatic factors, equipment used, method of application, method of storage, handling and disposal of waste, site characteristics (proximity of ground and underground waters, biodiversity and sensitivity of the environment. Microorganisms play an important role in pesticide degradation as they are able to utilize the biogenic elements from those compounds, as well as energy for their physiological processes. On the other hand, pesticides are more or less toxic substances that can have adverse effect on populations of microorganisms and prevent their development, reduce their abundance, deplete their taxonomic complexity and create communities with a lower level of diversity and reduced physiological activity.The article discusses complex interactions between pesticides and microorganisms in soil immediately after application and over the ensuing period. Data on changes in the abundance of some systematic and physiological groups of microorganisms, their microbial biomass and enzymatic activity caused under pesticide activity are discussed as indicators of these processes.

Dynamic size spectrometry of airborne microorganisms: Laboratory evaluation and calibration

Science.gov (United States)

Qian, Yinge; Willeke, Klaus; Ulevicius, Vidmantas; Grinshpun, Sergey A.; Donnelly, Jean

Bioaerosol samplers need to be calibrated for the microorganisms of interest. The Aerosizer, a relatively new aerodynamic size spectrometer, is shown to be a suitable dynamic instrument for the evaluation and calibration of such samplers in the laboratory, prior to their use in the field. It provides the necessary reference count against which the microbiological response of the sampler can be compared. It measures the health-significant aerodynamic diameters of microorganisms down to 0.5 μm, thus including most of the bacteria, fungi and pollen found in outdoor and indoor air environments. Comparison tests with a laser size spectrometer indicate that the suspension of microorganisms needs to be washed several times before aerosolization to avoid coating of the airborne microorganisms with nutrients and microbial slime from the suspension, and to reduce the residue particles to sizes below the lowest size of the aerosolized microorganisms.

Risk Assessment of Genetically Modified Microorganisms

DEFF Research Database (Denmark)

Jacobsen, B. L.; Wilcks, Andrea

2001-01-01

the industry, national administration and research institutions were gathered to discuss which elements should be considered in a risk assessment of genetically modified microorganisms used as food or food ingredients. The existing EU and national regulations were presented, together with the experiences......The rapid development of recombinant DNA techniques for food organisms urges for an ongoing discussion on the risk assessment of both new as traditional use of microorganisms in food production. This report, supported by the Nordic Council of Ministers, is the result of a workshop where people from...... with risk assessment of these organisms in each Nordic country....

Integrating PCR Theory and Bioinformatics into a Research-oriented Primer Design Exercise

OpenAIRE

Robertson, Amber L.; Phillips, Allison R.

2008-01-01

Polymerase chain reaction (PCR) is a conceptually difficult technique that embodies many fundamental biological processes. Traditionally, students have struggled to analyze PCR results due to an incomplete understanding of the biological concepts (theory) of DNA replication and strand complementarity. Here we describe the design of a novel research-oriented exercise that prepares students to design DNA primers for PCR. Our exercise design includes broad and specific learning goals and assessm...

Compost supplementation with nutrients and microorganisms in composting process.

Science.gov (United States)

Sánchez, Óscar J; Ospina, Diego A; Montoya, Sandra

2017-11-01

The composting is an aerobic, microorganism-mediated, solid-state fermentation process by which different organic materials are transformed into more stable compounds. The product obtained is the compost, which contributes to the improvement of physical, chemical and microbiological properties of the soil. However, the compost usage in agriculture is constrained because of its long-time action and reduced supply of nutrients to the crops. To enhance the content of nutrients assimilable by the plants in the compost, its supplementation with nutrients and inoculation with microorganisms have been proposed. The objective of this work was to review the state of the art on compost supplementation with nutrients and the role played by the microorganisms involved (or added) in their transformation during the composting process. The phases of composting are briefly compiled and different strategies for supplementation are analyzed. The utilization of nitrogenous materials and addition of microorganisms fixing nitrogen from the atmosphere or oxidizing ammonia into more assimilable for plants nitrogenous forms are analyzed. Several strategies for nitrogen conservation during composting are presented as well. The supplementation with phosphorus and utilization of microorganisms solubilizing phosphorus and potassium are also discussed. Main groups of microorganisms relevant during the composting process are described as well as most important strategies to identify them. In general, the development of this type of nutrient-enriched bio-inputs requires research and development not only in the supplementation of compost itself, but also in the isolation and identification of microorganisms and genes allowing the degradation and conversion of nitrogenous substances and materials containing potassium and phosphorus present in the feedstocks undergoing the composting process. In this sense, most important research trends and strategies to increase nutrient content in the compost

Volatilization of Po by microorganisms at laboratory culture experiments

International Nuclear Information System (INIS)

Momoshima, N.; Ishida, A.; Yoshinaga, C.; Fukuda, A.

2005-01-01

The previous experiments proved the volatility of polonium form culture medium in which microorganisms were propagated from seed of seawater, river water or pond water, therefore we did not know what kind of species are responsible to Po volatility. To search microorganisms, which concerned with Po emission we carried out culture experiments using known microorganisms. Three microorganisms were examined; Escherichia coli K-12, Bacillus subtilis and Chromobacterium violaceum. The microorganisms were pre-cultured in LB medium at 30 degree C and a small portion of the pre-cultured was transferred to a culture bottle in which LB medium and 208 Po tracer were contained. The culture was done at 30 degree C with shaking the culture bottle and air passed through a filter was introduced. The Po volatilized was transferred into the trap vials in which scintillator for liquid scintillation counting (LSC) was contained. The Po activity was measured by LSC. All of the microorganisms examined volatilized Po but their ability was quite different each other. Highest ability was observed on Chromobacterium violaceum and then Escherichia coli K-12 followed by Bacillus subtilis, the relative magnitude of the ability was 10 2 , 10, 1, respectively. Chromobacterium violaceum and Escherichia coli K-12 showed high volatility for the first 24 h but Escherichia coli K-12 showed a decrease thereafter. However high volatility was continued on Chromobacterium violaceum during the culture. The low culture temperature suppressed Po volatility, supporting biologically mediated Po emission from the culture.

Microscale interactions between earthworms and microorganisms: a review

Directory of Open Access Journals (Sweden)

Zirbes, L.

2012-01-01

Full Text Available Microorganisms are well adapted to their soil microhabitat where they live together in consortia, interacting with other living members, including earthworms. This literature review consists of four sections that focus on microscale interactions between earthworms and microorganisms. The first part is devoted to nephridia symbiosis. Recent discoveries show that Verminephrobacter spp. is present as a symbiont in earthworm nephridia. The second section deals with earthworm food preference and focuses on the major hypotheses of foraging strategies. The third section presents evidence of gut symbionts and highlights the need for additional studies in this field. The last section of this review explains why microorganism activities are enhanced in burrows and casts of earthworms.

Microbial genome-enabled insights into plant-microorganism interactions.

Science.gov (United States)

Guttman, David S; McHardy, Alice C; Schulze-Lefert, Paul

2014-12-01

Advances in genome-based studies on plant-associated microorganisms have transformed our understanding of many plant pathogens and are beginning to greatly widen our knowledge of plant interactions with mutualistic and commensal microorganisms. Pathogenomics has revealed how pathogenic microorganisms adapt to particular hosts, subvert innate immune responses and change host range, as well as how new pathogen species emerge. Similarly, culture-independent community profiling methods, coupled with metagenomic and metatranscriptomic studies, have provided the first insights into the emerging field of research on plant-associated microbial communities. Together, these approaches have the potential to bridge the gap between plant microbial ecology and plant pathology, which have traditionally been two distinct research fields.

The environmental impact of mine wastes - roles of microorganisms and their significance in treatment of mine wastes

International Nuclear Information System (INIS)

Ledin, M.; Pedersen, K.

1996-01-01

Mine wastes constitute a potential source of contamination to the environment, as heavy metals and acid are released in large amounts. A great variety of microorganisms has been found in mine wastes and microbiological processes are usually responsible for the environmental hazard created by mine wastes. However, microorganisms can also be used to retard the adverse impact of mine wastes on the environment. Conventionally, the mine drainage as well as the waste itself can be treated with alkali to increase pH and precipitate metals. The main drawback of this method is that it has to be continuously repeated to be fully effective. There may also be negative effects on beneficial microorganisms. Several other treatment methods have been developed to stop weathering processes thereby reducing the environmental impact of mine wastes. The other main approach is to treat the drainage water. Various methods aim at using microorganisms for this in natural or engineered systems. Recently, much interest has been focused on the use of natural or artificial wetlands for treatment. In general, the activity of microorganisms is neglected in the design of mine waste treatment systems, and the treatments are created merely from a technical point of view. This can result in situations where unexpected microbial processes take over, and, in the worst scenario, the overall effect is opposite to the desired

Color-Removal by Microorganisms Isolated from Human Hands

Directory of Open Access Journals (Sweden)

Tsukasa Ito

2013-08-01

Full Text Available Microorganisms are essential for human life. Microorganisms decompose the carbon compounds in dead animals and plants and convert them into carbon dioxide. Intestinal bacteria assist in food digestion. Some vitamins are produced by bacteria that live in the intestines. Sewage and industrial wastewater are treated by activated sludge composed of microbial communities. All of these are due to the ability of microbes to produce many enzymes that can degrade chemicals. How do teachers make students understand that microorganisms are always associated with humans, and that microorganisms have the ability to degrade chemicals? The presence of microorganisms on humans can be shown by incubating agar plates after they are touched by the hands of students. The ability of microorganisms to degrade chemicals can be shown by an analytical measurement of the degradation of chemicals. When the chemicals are dyes (colorants in water, microbial activity on degradation of dyes can be demonstrated by observing a decreasing degree of color as a result of the enzymatic activity (e.g., azoreductase. Dyes are widely used in the textile, food, and cosmetic industries. They are generally resistant to conventional biological wastewater treatment systems such as the activated sludge process (4. The discharge of wastewater containing dye pollutes surface water. The ability of microorganisms to decolorize and degrade dyes has been widely investigated to use for bioremediation purposes (5. The goal of this tip is to understand the presence of bacteria on human skin and the ability of bacteria to degrade colorant chemicals (decolorization. In this tip, students first cultivate and isolate bacteria on their hands, and then examine potential decolorization activity of each bacterium by observing the degree of color of the liquid in tubes in which bacteria isolated from students’ hands were inoculated. Decolorization activity of bacterial isolates from human skin has been

A formal account of the dual extension of knowledge and concept in C-K design theory

NARCIS (Netherlands)

Hendriks, L.; Kazakci, A.O.; Marjanović, D.; Štorga, M.; Pavković, N.; Bojčetić, N.

2010-01-01

The paper presents a contribution to the formalization efforts of C-K design theory. First, we analyze the notion of "dual expansion of concepts and knowledge" in C-K design theory and we discuss how such a reasoning process can be modeled using first-order logic. Then, we present a basic formal

Cybernetic modeling of adaptive prediction of environmental changes by microorganisms.

Science.gov (United States)

Mandli, Aravinda R; Modak, Jayant M

2014-02-01

Microorganisms exhibit varied regulatory strategies such as direct regulation, symmetric anticipatory regulation, asymmetric anticipatory regulation, etc. Current mathematical modeling frameworks for the growth of microorganisms either do not incorporate regulation or assume that the microorganisms utilize the direct regulation strategy. In the present study, we extend the cybernetic modeling framework to account for asymmetric anticipatory regulation strategy. The extended model accurately captures various experimental observations. We use the developed model to explore the fitness advantage provided by the asymmetric anticipatory regulation strategy and observe that the optimal extent of asymmetric regulation depends on the selective pressure that the microorganisms experience. We also explore the importance of timing the response in anticipatory regulation and find that there is an optimal time, dependent on the extent of asymmetric regulation, at which microorganisms should respond anticipatorily to maximize their fitness. We then discuss the advantages offered by the cybernetic modeling framework over other modeling frameworks in modeling the asymmetric anticipatory regulation strategy. Copyright © 2013. Published by Elsevier Inc.

Antenna theory analysis and design

CERN Document Server

Balanis, Constantine A

2005-01-01

The discipline of antenna theory has experienced vast technological changes. In response, Constantine Balanis has updated his classic text, Antenna Theory, offering the most recent look at all the necessary topics. New material includes smart antennas and fractal antennas, along with the latest applications in wireless communications. Multimedia material on an accompanying CD presents PowerPoint viewgraphs of lecture notes, interactive review questions, Java animations and applets, and MATLAB features. Like the previous editions, Antenna Theory, Third Edition meets the needs of e

Microorganism Utilization for Synthetic Milk

Science.gov (United States)

Morford, Megan A.; Khodadad, Christina L.; Caro, Janicce I.; Spencer, LaShelle E.; Richards, Jeffery T.; Strayer, Richard F.; Birmele, Michele N.; Wheeler, Raymond M.

2014-01-01

A desired architecture for long duration spaceflight, like aboard the International Space Station or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of the Synthetic Biology project, Cow in a Column, was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel-through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) in order to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products. For future work, the production of the casein protein for milk would require the development of a genetically modified organism, which was beyond the scope of the original project. Additional trials would be needed to further refine the required

DMPD: Signaling pathways activated by microorganisms. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 17303405 Signaling pathways activated by microorganisms. Takeuchi O, Akira S. Curr ...Opin Cell Biol. 2007 Apr;19(2):185-91. Epub 2007 Feb 15. (.png) (.svg) (.html) (.csml) Show Signaling pathways activated by microorg...anisms. PubmedID 17303405 Title Signaling pathways activated by microorganisms. Auth

Mini-review: Inhibition of biofouling by marine microorganisms.

Science.gov (United States)

Dobretsov, Sergey; Abed, Raeid M M; Teplitski, Max

2013-01-01

Any natural or artificial substratum exposed to seawater is quickly fouled by marine microorganisms and later by macrofouling species. Microfouling organisms on the surface of a substratum form heterogenic biofilms, which are composed of multiple species of heterotrophic bacteria, cyanobacteria, diatoms, protozoa and fungi. Biofilms on artificial structures create serious problems for industries worldwide, with effects including an increase in drag force and metal corrosion as well as a reduction in heat transfer efficiency. Additionally, microorganisms produce chemical compounds that may induce or inhibit settlement and growth of other fouling organisms. Since the last review by the first author on inhibition of biofouling by marine microbes in 2006, significant progress has been made in the field. Several antimicrobial, antialgal and antilarval compounds have been isolated from heterotrophic marine bacteria, cyanobacteria and fungi. Some of these compounds have multiple bioactivities. Microorganisms are able to disrupt biofilms by inhibition of bacterial signalling and production of enzymes that degrade bacterial signals and polymers. Epibiotic microorganisms associated with marine algae and invertebrates have a high antifouling (AF) potential, which can be used to solve biofouling problems in industry. However, more information about the production of AF compounds by marine microorganisms in situ and their mechanisms of action needs to be obtained. This review focuses on the AF activity of marine heterotrophic bacteria, cyanobacteria and fungi and covers publications from 2006 up to the end of 2012.

Learning relationships from theory to design

Directory of Open Access Journals (Sweden)

C. J.H. Fowler

1999-12-01

Full Text Available Over the last five years we have seen a very significant increase in the use of Information Communication Technologies (ICT in schools, colleges and university. For example in 1998, there were over 195 accredited US universities offering a thousand or more distance learning courses (Philips and Yager, 1998. By no means were all of these new courses associated with educational innovation. The speed and ease of implementation of Webbased approaches, in particular, is resulting in design by imitation of current courses and methods, with a real lack of innovation or utilization of the power inherent in technologybased learning. Although matters are improving (see for example Brown, 1999, part of the reason for this failure to innovate is, we argue, because of the large gap between theory and practice.

Competition between roots and microorganisms for nitrogen: mechanisms and ecological relevance

Science.gov (United States)

Kuzyakov, Yakov; Xu, Xingliang

2014-05-01

Demand of all living organisms on the same nutrients forms the basis for interspecific competition between plants and microorganisms in soils. This competition is especially strong in the rhizosphere. To evaluate competitive and mutualistic interactions between plants and microorganisms and to analyse ecological consequences of these interactions, we analysed 424 data pairs from 41 15N-labelling studies that investigated 15N redistribution between roots and microorganisms. Calculated Michaelis-Menten kinetics based on Km (Michaelis constant) and Vmax (maximum uptake capacity) values from 77 studies on the uptake of nitrate, ammonia, and amino acids by roots and microorganisms clearly showed that, shortly after nitrogen (N) mobilization from soil organic matter and litter, microorganisms take up most N. Lower Km values of microorganisms suggest that they are especially efficient at low N concentrations, but can also acquire more N at higher N concentrations (Vmax) compared with roots. Because of the unidirectional flow of nutrients from soil to roots, plants are the winners for N acquisition in the long run. Therefore, despite strong competition between roots and microorganisms for N, a temporal niche differentiation reflecting their generation times leads to mutualistic relationships in the rhizosphere. This temporal niche differentiation is highly relevant ecologically because it: protects ecosystems from N losses by leaching during periods of slow or no root uptake; continuously provides roots with available N according to plant demand; and contributes to the evolutionary development of mutualistic interactions between roots and microorganisms.

Theory-Generating Practice: Proposing a principle for learning design

Directory of Open Access Journals (Sweden)

Mie Buhl

2016-06-01

Full Text Available This contribution proposes a principle for learning design: Theory-Generating Practice (TGP as an alternative to the way university courses often are taught and structured with a series of theoretical lectures separate from practical experience and concluding with an exam or a project. The aim is to contribute to a development of theoretical frameworks for learning designs by suggesting TGP which may lead to new practices and turn the traditional dramaturgy for teaching upside down. TGP focuses on embodied experience prior to text reading and lectures to enhance theoretical knowledge building and takes tacit knowledge into account. The article introduces TGP and contextualizes it to a Danish tradition of didactics as well as discusses it in relation to contemporary conceptual currents of didactic design and learning design. This is followed by a theoretical framing of TGP, and is discussed through three empirical examples from bachelor and master programs involving technology, and showing three ways of practicing it.

Theory-Generating Practice: Proposing a principle for learning design

Directory of Open Access Journals (Sweden)

Mie Buhl

2016-05-01

Full Text Available This contribution proposes a principle for learning design: Theory-Generating Practice (TGP as an alternative to the way university courses often are taught and structured with a series of theoretical lectures separate from practical experience and concluding with an exam or a project. The aim is to contribute to a development of theoretical frameworks for learning designs by suggesting TGP which may lead to new practices and turn the traditional dramaturgy for teaching upside down. TGP focuses on embodied experience prior to text reading and lectures to enhance theoretical knowledge building and takes tacit knowledge into account. The article introduces TGP and contextualizes it to a Danish tradition of didactics as well as discusses it in relation to contemporary conceptual currents of didactic design and learning design. This is followed by a theoretical framing of TGP, and is discussed through three empirical examples from bachelor and master programs involving technology, and showing three ways of practicing it.

Design of Mobile Augmented Reality in Health Care Education: A Theory-Driven Framework

Science.gov (United States)

Lilienthal, Anneliese; Shluzas, Lauren Aquino; Masiello, Italo; Zary, Nabil

2015-01-01

Background Augmented reality (AR) is increasingly used across a range of subject areas in health care education as health care settings partner to bridge the gap between knowledge and practice. As the first contact with patients, general practitioners (GPs) are important in the battle against a global health threat, the spread of antibiotic resistance. AR has potential as a practical tool for GPs to combine learning and practice in the rational use of antibiotics. Objective This paper was driven by learning theory to develop a mobile augmented reality education (MARE) design framework. The primary goal of the framework is to guide the development of AR educational apps. This study focuses on (1) identifying suitable learning theories for guiding the design of AR education apps, (2) integrating learning outcomes and learning theories to support health care education through AR, and (3) applying the design framework in the context of improving GPs’ rational use of antibiotics. Methods The design framework was first constructed with the conceptual framework analysis method. Data were collected from multidisciplinary publications and reference materials and were analyzed with directed content analysis to identify key concepts and their relationships. Then the design framework was applied to a health care educational challenge. Results The proposed MARE framework consists of three hierarchical layers: the foundation, function, and outcome layers. Three learning theories—situated, experiential, and transformative learning—provide foundational support based on differing views of the relationships among learning, practice, and the environment. The function layer depends upon the learners’ personal paradigms and indicates how health care learning could be achieved with MARE. The outcome layer analyzes different learning abilities, from knowledge to the practice level, to clarify learning objectives and expectations and to avoid teaching pitched at the wrong level

Effects of heat-activated persulfate oxidation on soil microorganisms

DEFF Research Database (Denmark)

Tsitonaki, Aikaterini; Smets, Barth F.; Bjerg, Poul Løgstrup

2008-01-01

/L). The results emphasize the necessity of using multiple toxicity assays and indigenous cultures in order to realistically assess the potential effects of in situ chemical oxidation on soil microorganisms. A comparison to other studies suggests that the effects of activated persulfate on soil microorganisms...

Biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.

Science.gov (United States)

Satpute, Surekha K; Banat, Ibrahim M; Dhakephalkar, Prashant K; Banpurkar, Arun G; Chopade, Balu A

2010-01-01

Marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. Among the various bioactive compounds, biosurfactant (BS)/bioemulsifiers (BE) are attracting major interest and attention due to their structural and functional diversity. The versatile properties of surface active molecules find numerous applications in various industries. Marine microorganisms such as Acinetobacter, Arthrobacter, Pseudomonas, Halomonas, Myroides, Corynebacteria, Bacillus, Alteromonas sp. have been studied for production of BS/BE and exopolysaccharides (EPS). Due to the enormity of marine biosphere, most of the marine microbial world remains unexplored. The discovery of potent BS/BE producing marine microorganism would enhance the use of environmental biodegradable surface active molecule and hopefully reduce total dependence or number of new application oriented towards the chemical synthetic surfactant industry. Our present review gives comprehensive information on BS/BE which has been reported to be produced by marine microorganisms and their possible potential future applications.

Virtual patient design: exploring what works and why. A grounded theory study.

Science.gov (United States)

Bateman, James; Allen, Maggie; Samani, Dipti; Kidd, Jane; Davies, David

2013-06-01

Virtual patients (VPs) are online representations of clinical cases used in medical education. Widely adopted, they are well placed to teach clinical reasoning skills. International technology standards mean VPs can be created, shared and repurposed between institutions. A systematic review has highlighted the lack of evidence to support which of the numerous VP designs may be effective, and why. We set out to research the influence of VP design on medical undergraduates. This is a grounded theory study into the influence of VP design on undergraduate medical students. Following a review of the literature and publicly available VP cases, we identified important design properties. We integrated them into two substantial VPs produced for this research. Using purposeful iterative sampling, 46 medical undergraduates were recruited to participate in six focus groups. Participants completed both VPs, an evaluation and a 1-hour focus group discussion. These were digitally recorded, transcribed and analysed using grounded theory, supported by computer-assisted analysis. Following open, axial and selective coding, we produced a theoretical model describing how students learn from VPs. We identified a central core phenomenon designated 'learning from the VP'. This had four categories: VP Construction; External Preconditions; Student-VP Interaction, and Consequences. From these, we constructed a three-layer model describing the interactions of students with VPs. The inner layer consists of the student's cognitive and behavioural preconditions prior to sitting a case. The middle layer considers the VP as an 'encoded object', an e-learning artefact and as a 'constructed activity', with associated pedagogic and organisational elements. The outer layer describes cognitive and behavioural change. This is the first grounded theory study to explore VP design. This original research has produced a model which enhances understanding of how and why the delivery and design of VPs

The ReflecTable: Bridging the Gap between Theory and Practice in Design Education

DEFF Research Database (Denmark)

Hook, Jonathan; Hjermitslev, Thomas; Iversen, Ole Sejer

The ReflecTable is a digital learning environment that explores how design games and video-led reflection might be combined to bridge the gap between the theoretical and practical components of design education. The concept seeks to leverage the qualities of exploratory design games and video...... to inspire design students to critically reflect upon the relationship between their evolving design practices and the theories and techniques they are taught in lectures, by allowing them to capture, review and reflect upon short videos of a design game. In this paper, we present the ReflecTable design...

78 FR 42451 - Animal Feeds Contaminated With Salmonella Microorganisms

Science.gov (United States)

2013-07-16

.... FDA-2013-N-0253] Animal Feeds Contaminated With Salmonella Microorganisms AGENCY: Food and Drug... revoking an advisory opinion on animal feeds contaminated with Salmonella microorganisms. This action is... articulated in a final compliance policy guide (CPG) on Salmonella in food for animals. DATES: This rule is...

Competition between roots and microorganisms for nitrogen: mechanisms and ecological relevance.

Science.gov (United States)

Kuzyakov, Yakov; Xu, Xingliang

2013-05-01

Demand of all living organisms on the same nutrients forms the basis for interspecific competition between plants and microorganisms in soils. This competition is especially strong in the rhizosphere. To evaluate competitive and mutualistic interactions between plants and microorganisms and to analyse ecological consequences of these interactions, we analysed 424 data pairs from 41 (15)N-labelling studies that investigated (15)N redistribution between roots and microorganisms. Calculated Michaelis-Menten kinetics based on K(m) (Michaelis constant) and V(max) (maximum uptake capacity) values from 77 studies on the uptake of nitrate, ammonia, and amino acids by roots and microorganisms clearly showed that, shortly after nitrogen (N) mobilization from soil organic matter and litter, microorganisms take up most N. Lower K(m) values of microorganisms suggest that they are especially efficient at low N concentrations, but can also acquire more N at higher N concentrations (V(max)) compared with roots. Because of the unidirectional flow of nutrients from soil to roots, plants are the winners for N acquisition in the long run. Therefore, despite strong competition between roots and microorganisms for N, a temporal niche differentiation reflecting their generation times leads to mutualistic relationships in the rhizosphere. This temporal niche differentiation is highly relevant ecologically because it: protects ecosystems from N losses by leaching during periods of slow or no root uptake; continuously provides roots with available N according to plant demand; and contributes to the evolutionary development of mutualistic interactions between roots and microorganisms. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles

Science.gov (United States)

Rozanov, A. Yu; Astafieva, M. M.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

2009-01-01

Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

Functional Properties of Microorganisms in Fermented Foods

Directory of Open Access Journals (Sweden)

Jyoti Prakash Tamang

2016-04-01

Full Text Available Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers.

Role of Microorganisms in the Removal of Radionuclides from Soil

International Nuclear Information System (INIS)

Bashandy, A.S.

2007-01-01

Resistance to radio nuclides and their accumulation by bacteria is a wide spread phenomenon that can be explored for the improvement of the environment. Metal resistant bacteria have developed very efficient and varying mechanisms for tolerating high levels of. toxic metals and thus hold potential for controlling heavy metal pollution. This property has been successfully applied for metal removal from soil. A total of 59 microorganisms were isolated from 5 locations in Sinai Desert. The microorganisms were examined for resistance to strontium, cobalt and cesium by spot technique on two kinds of media containing metals, Nutrient agar and King B agar. The resistant microorganisms were identified morphologically by Gram stain. The microorganisms were resistant to Sr and Cs at concentrations up to 200 mg/I and while Co proved to be toxic at a concentration of 100 mg/ I. The mechanisms of metal resistance to high concentrations were studied. Evidence show that the isolated microorganisms can uptake high concentrations of the studied elements. The results also, indicated that no binding proteins are released in the environment of the studied isolate

Stepped-frequency radar sensors theory, analysis and design

CERN Document Server

Nguyen, Cam

2016-01-01

This book presents the theory, analysis and design of microwave stepped-frequency radar sensors. Stepped-frequency radar sensors are attractive for various sensing applications that require fine resolution. The book consists of five chapters. The first chapter describes the fundamentals of radar sensors including applications followed by a review of ultra-wideband pulsed, frequency-modulated continuous-wave (FMCW), and stepped-frequency radar sensors. The second chapter discusses a general analysis of radar sensors including wave propagation in media and scattering on targets, as well as the radar equation. The third chapter addresses the analysis of stepped-frequency radar sensors including their principles and design parameters. Chapter 4 presents the development of two stepped-frequency radar sensors at microwave and millimeter-wave frequencies based on microwave integrated circuits (MICs), microwave monolithic integrated circuits (MMICs) and printed-circuit antennas, and discusses their signal processing....

Dialectical Inquiry as an Instructional Heuristic in Organization Theory and Design.

Science.gov (United States)

Dehler, Gordon E.; Welsh, M. Ann

1993-01-01

A strategy for teaching undergraduate organization theory and design uses dialectical inquiry (thesis-antithesis-synthesis) and involves students actively in classroom learning. Concepts are introduced through dichotomies as typically introduced in texts; discussion elaborates grey areas. Case analysis by this method conveys the often ambiguous…

Biodegradation of oil palm empty fruit bunch by composite micro-organisms

International Nuclear Information System (INIS)

Yusri Atan; Mat Rasol Awang; Mohammed Omar; Azizah Hashim; Tamikazu Kume; Shoji Hashimoto

1998-01-01

A comparison study on the comparative biodegradation ability on EFB by five groups of composite micro-organisms [Organomine, Thomas, Ohres C, Ohres II and micro-organisms from POME (palm oil mill effluent)] has been performed with the aim of producing a compost at a faster rate than that by natural biodegradation. The experiment was carried out by mixing 50 gram EFB (dry weight basis) with 3% ammonium sulphate to which was added 1% composite micro-organisms and water to produce a composting media of moisture content about 60%. Respiration of composite micro-organisms as well as from decomposition of EFB releasing CO sub 2. The choice of useful micro-organisms was based on its ability to degrade EFB as reflected by higher evolution rate of CO sub 2 released and retaining higher percentage of nitrogen in the final product

Biofuel production by recombinant microorganisms

Science.gov (United States)

Liao, James C.; Atsumi, Shota; Cann, Anthony F.

2017-07-04

Provided herein are metabolically-modified microorganisms useful for producing biofuels. More specifically, provided herein are methods of producing high alcohols including isobutanol, 1-butanol, 1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-phenylethanol from a suitable substrate.

Physiologically anaerobic microorganisms of the deep subsurface

Energy Technology Data Exchange (ETDEWEB)

Stevens, S.E. Jr.; Chung, K.T.

1991-06-01

This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

Using Diffusion of Innovation Theory to Promote Universally Designed College Instruction

Science.gov (United States)

Scott, Sally; McGuire, Joan

2017-01-01

Universal Design applied to college instruction has evolved and rapidly spread on an international scale. Diffusion of Innovation theory is described and used to identify patterns of change in this trend. Implications and strategies are discussed for promoting this inclusive approach to teaching in higher education.

Design of structurally colored surfaces based on scalar diffraction theory

DEFF Research Database (Denmark)

Johansen, Villads Egede; Andkjær, Jacob Anders; Sigmund, Ole

2014-01-01

In this paper we investigate the possibility of controlling the color and appearance of surfaces simply by modifying the height profile of the surface on a nanoscale level. The applications for such methods are numerous: new design possibilities for high-end products, color engraving on any highly...... reflective surface, paint-free text and coloration, UV-resistant coloring, etc. In this initial study, the main focus is on finding a systematic way to obtain these results. For now the simulation and optimization is based on a simple scalar diffraction theory model. From the results, several design issues...

Theory-informed design of values clarification methods: a cognitive psychological perspective on patient health-related decision making.

Science.gov (United States)

Pieterse, Arwen H; de Vries, Marieke; Kunneman, Marleen; Stiggelbout, Anne M; Feldman-Stewart, Deb

2013-01-01

Healthcare decisions, particularly those involving weighing benefits and harms that may significantly affect quality and/or length of life, should reflect patients' preferences. To support patients in making choices, patient decision aids and values clarification methods (VCM) in particular have been developed. VCM intend to help patients to determine the aspects of the choices that are important to their selection of a preferred option. Several types of VCM exist. However, they are often designed without clear reference to theory, which makes it difficult for their development to be systematic and internally coherent. Our goal was to provide theory-informed recommendations for the design of VCM. Process theories of decision making specify components of decision processes, thus, identify particular processes that VCM could aim to facilitate. We conducted a review of the MEDLINE and PsycINFO databases and of references to theories included in retrieved papers, to identify process theories of decision making. We selected a theory if (a) it fulfilled criteria for a process theory; (b) provided a coherent description of the whole process of decision making; and (c) empirical evidence supports at least some of its postulates. Four theories met our criteria: Image Theory, Differentiation and Consolidation theory, Parallel Constraint Satisfaction theory, and Fuzzy-trace Theory. Based on these, we propose that VCM should: help optimize mental representations; encourage considering all potentially appropriate options; delay selection of an initially favoured option; facilitate the retrieval of relevant values from memory; facilitate the comparison of options and their attributes; and offer time to decide. In conclusion, our theory-based design recommendations are explicit and transparent, providing an opportunity to test each in a systematic manner. Copyright © 2012 Elsevier Ltd. All rights reserved.

Magnetotaxy in microorganisms of Rio de Janeiro region: an overview

International Nuclear Information System (INIS)

Barros, H.G. de P.L. de; Esquivel, D.M.S.

1983-01-01

Some characteristics of several magnetotactic microorganisms found in sediments collected in Rio de Janeiro region are presented. The study of magnetic characteristics of these microorganisms indicate some general properties of the magnetotaxy phenomenons. (L.C.) [pt

A robust rotorcraft flight control system design methodology utilizing quantitative feedback theory

Science.gov (United States)

Gorder, Peter James

1993-01-01

Rotorcraft flight control systems present design challenges which often exceed those associated with fixed-wing aircraft. First, large variations in the response characteristics of the rotorcraft result from the wide range of airspeeds of typical operation (hover to over 100 kts). Second, the assumption of vehicle rigidity often employed in the design of fixed-wing flight control systems is rarely justified in rotorcraft where rotor degrees of freedom can have a significant impact on the system performance and stability. This research was intended to develop a methodology for the design of robust rotorcraft flight control systems. Quantitative Feedback Theory (QFT) was chosen as the basis for the investigation. Quantitative Feedback Theory is a technique which accounts for variability in the dynamic response of the controlled element in the design robust control systems. It was developed to address a Multiple-Input Single-Output (MISO) design problem, and utilizes two degrees of freedom to satisfy the design criteria. Two techniques were examined for extending the QFT MISO technique to the design of a Multiple-Input-Multiple-Output (MIMO) flight control system (FCS) for a UH-60 Black Hawk Helicopter. In the first, a set of MISO systems, mathematically equivalent to the MIMO system, was determined. QFT was applied to each member of the set simultaneously. In the second, the same set of equivalent MISO systems were analyzed sequentially, with closed loop response information from each loop utilized in subsequent MISO designs. The results of each technique were compared, and the advantages of the second, termed Sequential Loop Closure, were clearly evident.

An experiment designed to verify the general theory of relativity

International Nuclear Information System (INIS)

Surdin, Maurice

1960-01-01

The project for an experiment which uses the effect of gravitation on Maser-type clocks placed on the ground at two different heights and which is designed to verify the general theory of relativity. Reprint of a paper published in Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 299-301, sitting of 11 January 1960 [fr

An Approach for Assessing the Signature Quality of Various Chemical Assays when Predicting the Culture Media Used to Grow Microorganisms

Energy Technology Data Exchange (ETDEWEB)

Holmes, Aimee E.; Sego, Landon H.; Webb-Robertson, Bobbie-Jo M.; Kreuzer, Helen W.; Anderson, Richard M.; Unwin, Stephen D.; Weimar, Mark R.; Tardiff, Mark F.; Corley, Courtney D.

2013-02-01

We demonstrate an approach for assessing the quality of a signature system designed to predict the culture medium used to grow a microorganism. The system was comprised of four chemical assays designed to identify various ingredients that could be used to produce the culture medium. The analytical measurements resulting from any combination of these four assays can be used in a Bayesian network to predict the probabilities that the microorganism was grown using one of eleven culture media. We evaluated combinations of the signature system by removing one or more of the assays from the Bayes network. We measured and compared the quality of the various Bayes nets in terms of fidelity, cost, risk, and utility, a method we refer to as Signature Quality Metrics

Some estimates of the continuous cultivation of microorganisms

Directory of Open Access Journals (Sweden)

G. V. Alekseev

2017-01-01

Full Text Available The proteins, fats and carbohydrates received by the person traditionally from animal and vegetable sources don't cover all increasing needs of mankind any more today. At the same time proteins and fats of microorganisms with success can replace proteins and fats of a traditional origin. As protein producers microorganisms at the high content of protein in biomass and high growth rate of microorganisms have certain advantages. The present article is devoted to questions of numerical modeling of processes of cultivation of microorganisms. On the basis of the known model offered Mono in which saturation of growth rate of culture at increase in initial concentration of a substratum of S0 is considered the system of the differential equations describing the happening processes in that number before achievement of stationarity is written down. At the same time dependence of separate sizes, the systems entering the equations is insufficiently studied at change of parameters of process. The behavior of all system at violation of regulations is of interest or at unauthorized change of one of parameters. For studying of these questions numerical modeling is carried out and the basic picture of change of chemostate curves in these conditions is received

Is arsenic biotransformation a detoxification mechanism for microorganisms?

International Nuclear Information System (INIS)

Rahman, M. Azizur; Hassler, Christel

2014-01-01

Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As V , which is thermodynamically stable in oxic waters, and As III , which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As V , biotransform it to As III , then biomethylate it to methylarsenic (MetAs) forms. Although As III is more toxic than As V , As III is much more easily excreted from the cells than As V . Therefore, majority of researchers consider the reduction of As V to As III as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA V , dimethylarsonate; DMA V , and trimethylarsenic oxide; TMAO V ) and trimethylarsine (TMAO III ). However, biomethylation by microorganisms also produces monomethylarsenite (MMA III ) and dimethylarsenite (DMA III ), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data

40 CFR 725.67 - Applications to exempt new microorganisms from this part.

Science.gov (United States)

2010-07-01

...) The effects of the new microorganism on health and the environment. (ii) The magnitude of exposure of human beings and the environment to the new microorganism. (iii) The benefits of the new microorganism... economic consequences of granting or denying the exemption, including effects on the national economy...

Motion of magnetotactic microorganisms

International Nuclear Information System (INIS)

Esquivel, D.M.S.; Barros, H.G. de P.L. de.

1985-01-01

Magnetic moments for different magnetotactic microorganisms are obtained by electron microscopy analyses and studies of motion by optical microscopy. The results are analysed in terms of a model due to C.Bean. The considerations presented suggest that magnetotaxy is an efficient mechanism for orientation only if the time for reorientation is smaller than the cycles of environmental perturbations. (Author) [pt

Evolution, Metabolism and Biotechnological Usage of Methylotrophic Microorganisms

OpenAIRE

Oleg Mosin; Ignat Ignatov

2014-01-01

Methylotrophs – aerobic chemoheterotrophic microorganisms submitted by cocci and bacilli mobile forms, are inhabitants of reservoirs and soils of various type, where there are going on various processes of decomposition of organic substances with formation of the one-carbon С1-compounds and some С2-, and С3-compounds, capable to be assimilated by methylotrophs. These microorganisms assimilating carbon on ribuloso-5-monophospate and serine pathways, are allocated from soil ground, the sewage c...

Design theory of full face rock tunnel boring machine transition cutter edge angle and its application

Science.gov (United States)

Zhang, Zhaohuang; Meng, Liang; Sun, Fei

2013-05-01

At present, the inner cutters of a full face rock tunnel boring machine (TBM) and transition cutter edge angles are designed on the basis of indentation test or linear grooving test. The inner and outer edge angles of disc cutters are characterized as symmetric to each other with respect to the cutter edge plane. This design has some practical defects, such as severe eccentric wear and tipping, etc. In this paper, the current design theory of disc cutter edge angle is analyzed, and the characteristics of the rock-breaking movement of disc cutters are studied. The researching results show that the rotational motion of disc cutters with the cutter head gives rise to the difference between the interactions of inner rock and outer rock with the contact area of disc cutters, with shearing and extrusion on the inner rock and attrition on the outer rock. The wear of disc cutters at the contact area is unbalanced, among which the wear in the largest normal stress area is most apparent. Therefore, a three-dimensional model theory of rock breaking and an edge angle design theory of transition disc cutter are proposed to overcome the flaws of the currently used TBM cutter heads, such as short life span, camber wearing, tipping. And a corresponding equation is established. With reference to a specific construction case, the edge angle of the transition disc cutter has been designed based on the theory. The application of TBM in some practical project proves that the theory has obvious advantages in enhancing disc cutter life, decreasing replacement frequency, and making economic benefits. The proposed research provides a theoretical basis for the design of TBM three-dimensional disc cutters whose rock-breaking operation time can be effectively increased.

Screening of microorganisms for microbial enhanced oil recovery processes

Energy Technology Data Exchange (ETDEWEB)

Yonebayashi, H. [Japan National Oil Corp., Tokyo (Japan); Yoshida, S. [Japan Food Research Laboratiories, Tokyo (Japan). Div. of Microbiology; Ono, K. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

2000-01-01

The objective of this study is to screen effective microorganisms for the Microbial Enhanced Oil Recovery process (or simply as MEOR). Samples of drilling cuttings, formation water, and soil were collected from domestic drilling sites and oil fields. Moreover, samples of activated-sludge and compost were collected from domestic sewage treatment facility and food treatment facility. At first, microorganisms in samples were investigated by incubation with different media; then they were isolated. By two stage-screening based on metabolizing ability, 4 strains (Bacillus licheniformis TRC-18-2-a, Enterobacter cloacae TRC-322, Bacillus subtilis TRC-4118, and Bacillus subtilis TRC-4126) were isolated as effective microorganisms for oil recovery. B. licheniformis TRC-18-2-a is a multifunctional microorganism possessing excellent surfactant productivity, and in addition it has gas, acid and polymer productivities. E. cloacae TRC-332 has gas and acid producing abilities. B. subtilis TRC-4118 and TRC-4126 are effective biosurfactant producers, and they reduce the interfacial tension to 0.04 and 0.12 dyne/cm, respectively. (author)

Theory and simulation of DNA-coated colloids: a guide for rational design.

Science.gov (United States)

Angioletti-Uberti, Stefano; Mognetti, Bortolo M; Frenkel, Daan

2016-03-07

By exploiting the exquisite selectivity of DNA hybridization, DNA-coated colloids (DNACCs) can be made to self-assemble in a wide variety of structures. The beauty of this system stems largely from its exceptional versatility and from the fact that a proper choice of the grafted DNA sequences yields fine control over the colloidal interactions. Theory and simulations have an important role to play in the optimal design of self assembling DNACCs. At present, the powerful model-based design tools are not widely used, because the theoretical literature is fragmented and the connection between different theories is often not evident. In this Perspective, we aim to discuss the similarities and differences between the different models that have been described in the literature, their underlying assumptions, their strengths and their weaknesses. Using the tools described in the present Review, it should be possible to move towards a more rational design of novel self-assembling structures of DNACCs and, more generally, of systems where ligand-receptor are used to control interactions.

Theory Interpretation of Control System and Design Practice

International Nuclear Information System (INIS)

Jung, Heon Sul

2003-11-01

This book tells of theory interpretation of control system and design practice using automatic balancing weighing machine , including what control is, basic use of CEM Tool such as summary, work environment of CEM Tool, Symbol of CEM Tool, instruction of CEM Tool, drawing graph, and practice of making of CEM Tool, basic use of SIM Tool, driving test of sensor measurement motor such as LED, Pulse pick-up, answer test of RC circuit, structure of balancing weighing machine and wheel mathematical model, analysis of time response and frequency response of balancing weighing machine, and mathematical model and material property of balancing weighing machine.

The Effect of High Hydrostatic Pressure on Microorganisms in Food Preservation

OpenAIRE

M. Arici

2006-01-01

High hydrostatic pressure is a new food preservation technology known for its capacity to inactivate spoilage and pathogenic microorganisms. High-pressure treatments are receiving a great deal of attention for the inactivation of microorganisms in food processing, pressure instead of temperature is used as stabilizing factor. High hydrostatic pressure treatment is the most studied alternative process, many works reported successful results in inactivating a wide range of microorganisms under ...

Root Canal Microorganism Profiles on Upper Anterior Teeth of Apical Periodontitis

OpenAIRE

Riuwpassa, E. Irene

2013-01-01

Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance.this study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and chronic apical abscess. Samples we...

Root Canal Microorganisms Profiles of Upper Anterior Teeth with Periapical Lesion

OpenAIRE

Maria Tanumiharja; Irene E. Riewpassa; Mansjur Nasir; Burhanuddin D. Pasiga

2014-01-01

Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance. Objective: This study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and chronic apical abscess...

Computer Game Theories for Designing Motivating Educational Software: A Survey Study

Science.gov (United States)

Ang, Chee Siang; Rao, G. S. V. Radha Krishna

2008-01-01

The purpose of this study is to evaluate computer game theories for educational software. We propose a framework for designing engaging educational games based on contemporary game studies which includes ludology and narratology. Ludology focuses on the study of computer games as play and game activities, while narratology revolves around the…

Differentiation and detection of microorganisms using Fourier transform infrared photoacoustic spectroscopy

Science.gov (United States)

Irudayaraj, Joseph; Yang, Hong; Sakhamuri, Sivakesava

2002-03-01

Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) was used to differentiate and identify microorganisms on a food (apple) surface. Microorganisms considered include bacteria (Lactobacillus casei, Bacillus cereus, and Escherichia coli), yeast (Saccharomyces cerevisiae), and fungi (Aspergillus niger and Fusarium verticilliodes). Discriminant analysis was used to differentiate apples contaminated with the different microorganisms from uncontaminated apple. Mahalanobis distances were calculated to quantify the differences. The higher the value of the Mahalanobis distance metric between different microorganisms, the greater is their difference. Additionally, pathogenic (O157:H7) E. coli was successfully differentiated from non-pathogenic strains. Results demonstrate that FTIR-PAS spectroscopy has the potential to become a non-destructive analysis tool in food safety related research.

Progress in decontamination by halophilic microorganisms in saline wastewater and soil

International Nuclear Information System (INIS)

Zhuang Xuliang; Han Zhen; Bai Zhihui; Zhuang Guoqiang; Shim Hojae

2010-01-01

Environments with high-salt concentrations are often populated by dense microbial communities. Halophilic microorganisms can be isolated from different saline environments and different strains even belonging to the same genus have various applications. Wastewater and soil rich in both organic matter and salt are difficult to treat using conventional microorganisms typically found in wastewater treatment and soil bioremediation facilities. Studies on decontaminative capabilities and decontamination pathways of organic contaminants (i.e., aromatic compounds benzoate, cinnamate, 3-phenylpropionate, 4-hydroxybenzoic acid), heavy metals (i.e., tellurium, vanadium), and nutrients in the biological treatment of saline wastewater and soil by halophilic microorganisms are discussed in this review. - Review on the decontaminative capabilities of halophilic microorganisms in saline wastewater and soil.

Progress in decontamination by halophilic microorganisms in saline wastewater and soil

Energy Technology Data Exchange (ETDEWEB)

Zhuang Xuliang, E-mail: xlzhuang@rcees.ac.c [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Bureau of Science and Technology for Resources and Environment, Chinese Academy of Sciences, Beijing 100864 (China); Han Zhen [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Bai Zhihui; Zhuang Guoqiang [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Shim Hojae [Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau (China)

2010-05-15

Environments with high-salt concentrations are often populated by dense microbial communities. Halophilic microorganisms can be isolated from different saline environments and different strains even belonging to the same genus have various applications. Wastewater and soil rich in both organic matter and salt are difficult to treat using conventional microorganisms typically found in wastewater treatment and soil bioremediation facilities. Studies on decontaminative capabilities and decontamination pathways of organic contaminants (i.e., aromatic compounds benzoate, cinnamate, 3-phenylpropionate, 4-hydroxybenzoic acid), heavy metals (i.e., tellurium, vanadium), and nutrients in the biological treatment of saline wastewater and soil by halophilic microorganisms are discussed in this review. - Review on the decontaminative capabilities of halophilic microorganisms in saline wastewater and soil.

Calculation of the radiative properties of photosynthetic microorganisms

International Nuclear Information System (INIS)

Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

2015-01-01

A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers–Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

Calculation of the radiative properties of photosynthetic microorganisms

Science.gov (United States)

Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

2015-08-01

A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers-Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

Energy Technology Data Exchange (ETDEWEB)

Cai, Jun, E-mail: jun_cai@buaa.edu.cn [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Lan, Mingming; Zhang, Deyuan; Zhang, Wenqiang [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

2012-09-01

Highlights: Black-Right-Pointing-Pointer We use the microorganism cells as forming templates to fabricate the bio-based conductive particles. Black-Right-Pointing-Pointer The microorganism cells selected as forming templates are Spirulina platens, which are of natural helical shape and high aspect ratio. Black-Right-Pointing-Pointer The sliver-coated Spirulina cells are a kind of lightweight conductive particles. Black-Right-Pointing-Pointer The composites containing sliver-coated Spirulina cells exhibit a lower percolation value. - Abstract: In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of {phi}{sub c} and t were obtained.

Advancing the literature on designing audit and feedback interventions: identifying theory-informed hypotheses.

Science.gov (United States)

Colquhoun, Heather L; Carroll, Kelly; Eva, Kevin W; Grimshaw, Jeremy M; Ivers, Noah; Michie, Susan; Sales, Anne; Brehaut, Jamie C

2017-09-29

Audit and feedback (A&F) is a common strategy for helping health providers to implement evidence into practice. Despite being extensively studied, health care A&F interventions remain variably effective, with overall effect sizes that have not improved since 2003. Contributing to this stagnation is the fact that most health care A&F interventions have largely been designed without being informed by theoretical understanding from the behavioral and social sciences. To determine if the trend can be improved, the objective of this study was to develop a list of testable, theory-informed hypotheses about how to design more effective A&F interventions. Using purposive sampling, semi-structured 60-90-min telephone interviews were conducted with experts in theories related to A&F from a range of fields (e.g., cognitive, health and organizational psychology, medical decision-making, economics). Guided by detailed descriptions of A&F interventions from the health care literature, interviewees described how they would approach the problem of designing improved A&F interventions. Specific, theory-informed hypotheses about the conditions for effective design and delivery of A&F interventions were elicited from the interviews. The resulting hypotheses were assigned by three coders working independently into themes, and categories of themes, in an iterative process. We conducted 28 interviews and identified 313 theory-informed hypotheses, which were placed into 30 themes. The 30 themes included hypotheses related to the following five categories: A&F recipient (seven themes), content of the A&F (ten themes), process of delivery of the A&F (six themes), behavior that was the focus of the A&F (three themes), and other (four themes). We have identified a set of testable, theory-informed hypotheses from a broad range of behavioral and social science that suggest conditions for more effective A&F interventions. This work demonstrates the breadth of perspectives about A&F from non

Microorganisms having enhanced tolerance to inhibitors and stress

Energy Technology Data Exchange (ETDEWEB)

Brown, Steven D.; Yang, Shihui

2014-07-29

The present invention provides genetically modified strains of microorganisms that display enhanced tolerance to stress and/or inhibitors such as sodium acetate and vanillin. The enhanced tolerance can be achieved by increasing the expression of a protein of the Sm-like superfamily such as a bacterial Hfq protein and a fungal Sm or Lsm protein. Further, the present invention provides methods of producing alcohol from biomass materials by using the genetically modified microorganisms of the present invention.

Genomics-Based Identifcation of Microorganisms in Human Ocular Body Fluid

DEFF Research Database (Denmark)

Kirstahler, Philipp; Solborg Bjerrum, Søren; Friis-Møller, Alice

2018-01-01

genomes and (iii) the environment. Our metagenomic read classification revealed in nearly all cases the same microorganism that was determined in cultivation- and mass spectrometry-based analyses. For some patients, we identified the sequence type of the microorganism and antibiotic resistance genes...

Organotins and microorganisms. Yuki suzu kagobutsu to biseibutsu

Energy Technology Data Exchange (ETDEWEB)

Shinoda, S.; Onogi, H. (Okayama Univ., Okayama (Japan). Faculty of Pharmaceutical Sciences)

1992-08-10

Tributyltin (TBT) and triphenyltin have higher toxicity than other organotin compounds and are used as biocides, but in recent years the pollution of water and aquatic organisms has become a social problem. This paper describes the interaction between organotin compounds and microorganisms, centering on the decomposition of TBT. Part of microalgae whose activity is promoted by light or nutritive salts within an aquatic environment play an important role in TBT decomposition. Diatoms, and dinoflagellataes are mentioned as the examples. Moreover, an example in which microorganisms promote the transformation of inorganotin compounds to dimethyltin or trimethyltin is given. However, it is pointed out in this paper that the action of microorganisms relates greatly to the continuance of existence of organotins in environments, but the degradation efficiency is considered to be very low and prevention against pollution is of primary importance. 32 refs., 2 figs., 3 tabs.

Design-based research – issues in connecting theory, research and practice

DEFF Research Database (Denmark)

Kolmos, Anette

2015-01-01

the gap. But is this as easy as it sounds? The purpose of the article is to identify and discuss issues involved in applying DBR. The article is based on methodology chapters and essays from three PhD studies applying the DBR framework to implement problem and project based learning (PBL). The findings......During the last 20 years, design-based research (DBR) has become a popular methodology for connecting educational theory, research and practice. The missing link between educational theory, research and educational practice is an ongoing issue and DBR is seen as an integrated methodology to bridge...... indicate several key issues at both the scientific and personal level. Scientifically, the main issues are contribution to theory and the role of the researcher. At the personal level, it is an investment beyond normal research procedures to involve yourself as a researcher in curriculum change....

Rough Set Theory Based Fuzzy TOPSIS on Serious Game Design Evaluation Framework

Directory of Open Access Journals (Sweden)

Chung-Ho Su

2013-01-01

Full Text Available This study presents a hybrid methodology for solving the serious game design evaluation in which evaluation criteria are based on meaningful learning, ARCS motivation, cognitive load, and flow theory (MACF by rough set theory (RST and experts’ selection. The purpose of this study tends to develop an evaluation model with RST based fuzzy Delphi-AHP-TOPSIS for MACF characteristics. Fuzzy Delphi method is utilized for selecting the evaluation criteria, Fuzzy AHP is used for analyzing the criteria structure and determining the evaluation weight of criteria, and Fuzzy TOPSIS is applied to determine the sequence of the evaluations. A real case is also used for evaluating the selection of MACF criteria design for four serious games, and both the practice and evaluation of the case could be explained. The results show that the playfulness (C24, skills (C22, attention (C11, and personalized (C35 are determined as the four most important criteria in the MACF selection process. And evaluation results of case study point out that Game 1 has the best score overall (Game 1 > Game 3 > Game 2 > Game 4. Finally, proposed evaluation framework tends to evaluate the effectiveness and the feasibility of the evaluation model and provide design criteria for relevant multimedia game design educators.

Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

Science.gov (United States)

Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

2016-03-01

Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

A stochastic model simulating the capture of pathogenic micro-organisms by superparamagnetic particles in an isodynamic magnetic field

International Nuclear Information System (INIS)

Rotariu, O; Strachan, N J C; Badescu, V

2004-01-01

The method of immunomagnetic separation (IMS) has become an established technique to concentrate and separate animal cells, biologically active compounds and pathogenic micro-organisms from clinical, food and environmental matrices. One drawback of this technique is that the analysis is only possible for small sample volumes. We have developed a stochastic model that involves numerical simulations to optimize the process of concentration of pathogenic micro-organisms onto superparamagnetic carrier particles (SCPs) in a gradient magnetic field. Within the range of the system parameters varied in the simulations, optimal conditions favour larger particles with higher magnetite concentrations. The dependence on magnetic field intensity and gradient together with concentration of particles and micro-organisms was found to be less important for larger SCPs but these parameters can influence the values of the collision time for small particles. These results will be useful in aiding the design of apparatus for immunomagnetic separation from large volume samples

Gut Microorganisms Found Necessary for Successful Cancer Therapy | Poster

Science.gov (United States)

By Nancy Parrish, Staff Writer Humans play host to trillions of microorganisms that help our bodies perform basic functions, like digestion, growth, and fighting disease. In fact, bacterial cells outnumber the human cells in our bodies by 10 to 1.1 The tens of trillions of microorganisms thriving in our intestines are known as gut microbiota, and those that are not harmful to

Is arsenic biotransformation a detoxification mechanism for microorganisms?

Energy Technology Data Exchange (ETDEWEB)

Rahman, M. Azizur, E-mail: Mohammad.Rahman@uts.edu.au [Centre for Environmental Sustainability, School of the Environment, Faculty of Science, University of Technology, P.O. Box 123, Broadway, Sydney, NSW 2007 (Australia); Hassler, Christel [Marine and Lake Biogeochemistry, Institute F. A. Forel, University of Geneva, 10 rte de Suisse, Versoix, 1290 Switzerland (Switzerland)

2014-01-15

Arsenic (As) is extremely toxic to living organisms at high concentration. In aquatic systems, As exists in different chemical forms. The two major inorganic As (iAs) species are As{sup V}, which is thermodynamically stable in oxic waters, and As{sup III}, which is predominant in anoxic conditions. Photosynthetic microorganisms (e.g., phytoplankton and cyanobacteria) take up As{sup V}, biotransform it to As{sup III}, then biomethylate it to methylarsenic (MetAs) forms. Although As{sup III} is more toxic than As{sup V}, As{sup III} is much more easily excreted from the cells than As{sup V}. Therefore, majority of researchers consider the reduction of As{sup V} to As{sup III} as a detoxification process. The biomethylation process results in the conversion of toxic iAs to the less toxic pentavalent MetAs forms (monomethylarsonate; MMA{sup V}, dimethylarsonate; DMA{sup V}, and trimethylarsenic oxide; TMAO{sup V}) and trimethylarsine (TMAO{sup III}). However, biomethylation by microorganisms also produces monomethylarsenite (MMA{sup III}) and dimethylarsenite (DMA{sup III}), which are more toxic than iAs, as a result of biomethylation by the microorganisms, demonstrates the need to reconsider to what extent As biomethylation contributes to a detoxification process. In this review, we focused on the discussion of whether the biotransformation of As species in microorganisms is really a detoxification process with recent data.

Brain-grounded theory of temporal and spatial design in architecture and the environment

CERN Document Server

Ando, Yoichi

2016-01-01

In this book, brain-grounded theory of temporal and spatial design in architecture and the environment is discussed. The author believes that it is a key to solving such global problems as environmental disorders and severe climate change as well as conflicts that are caused by the ill-conceived notion of “time is money”. There are three phases or aspects of a person’s life: the physical life, the spiritual or mental life, and the third stage of life, when a person moves from middle age into old age and can choose what he or she wishes to do instead of simply what must be done. This book describes the temporal design of the environment based on the theory of subjective preference, which could make it possible for an individual to realize a healthy life in all three phases. In his previously published work, the present author wrote that the theory of subjective preference has been established for the sound and visual fields based on neural evidence, and that subjective preference is an overall response o...

A Formal Approach to User Interface Design using Hybrid System Theory, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Optimal Synthesis Inc.(OSI) proposes to develop an aiding tool for user interface design that is based on mathematical formalism of hybrid system theory. The...

On the use of contraction theory for the design of nonlinear observers for ocean vehicles

DEFF Research Database (Denmark)

Jouffroy, Jerome; Lottin, Jacques

and practice. This paper addresses the question of the applicability of contraction theory to the design of UGES observers for ocean vehicles. A relation between the concept of exponential convergence of a contracting system and uniform global exponential stability (UGES) is rst given. Then two contraction......Guaranteeing that traditional concepts of stability like uniform global exponential or asymptotic stability (UGES or UGAS) are veri ed when using design tools based on new concepts of stability may be of signicant importance. It is especially so when attempting to bridge the gap between theory...

Nested Reconfigurable Robots: Theory, Design, and Realization

Directory of Open Access Journals (Sweden)

Ning Tan

2015-07-01

Full Text Available Rather than the conventional classification method, we propose to divide modular and reconfigurable robots into intra-, inter-, and nested reconfigurations. We suggest designing the robot with nested reconfigurability, which utilizes individual robots with intra-reconfigurability capable of combining with other homogeneous/heterogeneous robots (inter-reconfigurability. The objective of this approach is to generate more complex morphologies for performing specific tasks that are far from the capabilities of a single module or to respond to programmable assembly requirements. In this paper, we discuss the theory, concept, and initial mechanical design of Hinged-Tetro, a self-reconfigurable module conceived for the study of nested reconfiguration. Hinged-Tetro is a mobile robot that uses the principle of hinged dissection of polyominoes to transform itself into any of the seven one-sided tetrominoes in a straightforward way. The robot can also combine with other modules for shaping complex structures or giving rise to a robot with new capabilities. Finally, the validation experiments verify the nested reconfigurability of Hinged-Tetro. Extensive tests and analyses of intra-reconfiguration are provided in terms of energy and time consumptions. Experiments using two robots validate the inter-reconfigur ability of the proposed module.

Marine microorganisms as potential biofactories for synthesis of metallic nanoparticles.

Science.gov (United States)

Manivasagan, Panchanathan; Nam, Seung Yun; Oh, Junghwan

2016-11-01

The use of marine microorganisms as potential biofactories for green synthesis of metallic nanoparticles is a relatively new field of research with considerable prospects. This method is eco-friendly, time saving, and inexpensive and can be easily scaled up for large-scale synthesis. The increasing need to develop simple, nontoxic, clean, and environmentally safe production methods for nanoparticles and to decrease environmental impact, minimize waste, and increase energy productivity has become important in this field. Marine microorganisms are tiny organisms that live in marine ecosystems and account for >98% of biomass of the world's ocean. Marine microorganisms synthesize metallic nanoparticles either intracellularly or extracellularly. Marine microbially-produced metallic nanoparticles have received considerable attention in recent years because of their expected impact on various applications such as medicine, energy, electronic, and space industries. The present review discusses marine microorganisms as potential biofactories for the green synthesis of metallic nanoparticles and their potential applications.

Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

International Nuclear Information System (INIS)

Fuska, J.; Fuskova, A.

1982-01-01

Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10 -4 to 10 -5 g.l -1 , that of Rn in the atmosphere was from 0.04 to 40 Bq.l -1 . Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin. (author)

Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

Energy Technology Data Exchange (ETDEWEB)

Fuska, J.; Fuskova, A. (Slovenska Vysoka Skola Technicka, Bratislava (Czechoslovakia). Chemickotechnologicka Fakulta); Jilek, R. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

1982-01-01

Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10/sup -4/ to 10/sup -5/ g.l/sup -1/, that of Rn in the atmosphere was from 0.04 to 40 Bq.l/sup -1/. Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin.

Use of Probiotic Microorganisms for Bio-Protective Aims

Directory of Open Access Journals (Sweden)

Filiz YANGILAR

2015-03-01

Full Text Available It was known that some diseases can be treated as the result of the use of antibiotics in certain periods and at certain dosages while inactivating and deteriorating normal microorganisms performing useful activities in human metabolism (in especially intestinal flora. It was occured that after the use of antibiotics, some defects can be seen resulting from antibiotics (such as allergy, diarrhea, gas formation etc. With this aim, nutraceutics and functional food have gained importance over the last years and consumers began to be interested in probiotics, natural antioxidants, dietary fibres, products with low calorie and cholesterol contents, especially the products containing probioticbacteria. Bacteriocins produced by probiotic bacteria can play important roles as food protective and safeguarding since they can compete with unwanted or pathogen microorganisms survive in the media and colonize in intestines. In this review, is aimed to emphasis bioprotective compounds, advantages and disadvantages of biopreservation method and the importance of the mechanisms of probiotic microorganisms.

Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

Directory of Open Access Journals (Sweden)

Agnieszka Joanna Brodowska

2017-10-01

Full Text Available The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum on a heterogeneous matrix (juniper berries, cardamom seeds initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively. Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min and contact time (up to 20 min. The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process.

Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

Science.gov (United States)

Brodowska, Agnieszka Joanna; Nowak, Agnieszka; Kondratiuk-Janyska, Alina; Piątkowski, Marcin; Śmigielski, Krzysztof

2017-01-01

The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum) on a heterogeneous matrix (juniper berries, cardamom seeds) initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively). Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min) and contact time (up to 20 min). The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process. PMID:28991199

Microorganisms' mediated reduction of β-ketoesters

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... Whole cells usually express a multitude of enzymatic activities; therefore an ... Each microorganism was cultivated for the biomass development on specific medium ..... Ketoester reductase for conversion of keto acid esters to ...

Threshold Dynamics of a Stochastic Chemostat Model with Two Nutrients and One Microorganism

Directory of Open Access Journals (Sweden)

Jian Zhang

2017-01-01

Full Text Available A new stochastic chemostat model with two substitutable nutrients and one microorganism is proposed and investigated. Firstly, for the corresponding deterministic model, the threshold for extinction and permanence of the microorganism is obtained by analyzing the stability of the equilibria. Then, for the stochastic model, the threshold of the stochastic chemostat for extinction and permanence of the microorganism is explored. Difference of the threshold of the deterministic model and the stochastic model shows that a large stochastic disturbance can affect the persistence of the microorganism and is harmful to the cultivation of the microorganism. To illustrate this phenomenon, we give some computer simulations with different intensity of stochastic noise disturbance.

Effects of phosphate-solubilizing bacteria, native microorganisms, and rock dust on Jatropha curcas L. growth.

Science.gov (United States)

Santana, E B; Marques, E L S; Dias, J C T

2016-10-05

Microorganisms with the ability to release nutrients to the soil from insoluble sources may be useful for plant cultivation. We evaluated the growth-promoting effect on Jatropha curcas L. of phosphate-solubilizing bacteria (PSB) and the native microbiota in soil with or without rock dust. J. curcas L. is important for biodiesel production. The experiments were performed in a greenhouse under a random-statistical design with 14 replicates. The soil received increasing dosages of rock dust. The presence of resident microorganisms and PSB inoculum was correlated with plant height, biomass production, and phosphorus content in plants for 120 days. Native soil microorganisms were detected and identified using denaturing gradient gel electrophoresis and DNA sequence analysis. Several bacterial populations belonged to the genus Bacillus. Populations associated with the phyla Chytridiomycota and Ascomycota were detected among the fungi. The best results for the variable plant height were correlated with the presence of resident microbiota and rock dust until the end of the experiment. The largest biomass production and the highest content of phosphorus occurred in the presence of soil-resident microbiota only up to 120 days. No significant effects were observed for biomass production with the use of PSB combined with rock dust. J. curcas L. under the influence of only resident microbiota showed the best plant growth results. Future research will focus on the specificity of resident microbiota activity in plant growth promotion and the isolation of these microorganisms to produce a new inoculum to be tested in various plants.

Five roles for using theory and evidence in the design and testing of behavior change interventions.

Science.gov (United States)

Bartholomew, L Kay; Mullen, Patricia Dolan

2011-01-01

The prevailing wisdom in the field of health-related behavior change is that well-designed and effective interventions are guided by theory. Using the framework of intervention mapping, we describe and provide examples of how investigators can effectively select and use theory to design, test, and report interventions. We propose five roles for theory and evidence about theories: a) identification of behavior and determinants of behavior related to a specified health problem (i.e., the logic model of the problem); b) explication of a causal model that includes theoretical constructs for producing change in the behavior of interest (i.e., the logic model of change); c) selection of intervention methods and delivery of practical applications to achieve changes in health behavior; d) evaluation of the resulting intervention including theoretical mediating variables; and e) reporting of the active ingredients of the intervention together with the evaluation results. In problem-driven applied behavioral or social science, researchers use one or multiple theories, empiric evidence, and new research, both to assess a problem and to solve or prevent a problem. Furthermore, the theories for description of the problem may differ from the theories for its solution. In an applied approach, the main focus is on solving problems regarding health behavior change and improvement of health outcomes, and the criteria for success are formulated in terms of the problem rather than the theory. Resulting contributions to theory development may be quite useful, but they are peripheral to the problem-solving process.

Selection of Suitable Microorganism for Biocatalytic Oxidation Reaction of Racemic Propranolol

Directory of Open Access Journals (Sweden)

Rahime SONGÜR

2017-12-01

Full Text Available Propranolol is one of the β-blockers which are pharmaceutically important, especially used for treatment of cardiovasculer disease. In this study, the production of enantiomerically pure propranolol was aimed via biocatalytic deracemization including tandem oxidation-reduction reactions of racemic propranolol. Within this content, firstly suitable microorganism for the oxidation of racemic propranolol was investigated. Alcohol dehydrogenase (ADH enzyme for oxidation of propranolol and NADH oxidase enzyme for cofactor regeneration were necessary for the oxidation reactions. For this reason, ADH and NADH oxidase enzymes activities of different microorganisms were measured to select the microorganism for using as enzyme source. These microorganisms are Lactobacillus kefir NRRL B-1839, Rhodotorula glutunis DSM 70398, Rhizopus oryzae CBS 111718, Rhizopus arhizus. The highest ADH and NADH oxidase activities were obtained for L. kefir.

Gestalt Theory in Visual Screen Design — A New Look at an old subject

OpenAIRE

Chang, D.; Dooley, L.; Tuovinen, J. E

2002-01-01

Although often presented as a single basis for educational visual screen design, Gestalt theory is not a single small set of visual principles uniformly applied by all designers. In fact, it appears that instructional visual design literature often deals with only a small set of Gestalt laws. In this project Gestalt literature was consulted to distil the most relevant Gestalt laws for educational visual screen design. Eleven laws were identified. They deal with balance/symmetry, continuation,...

Microorganisms present on peripheral intravenous needleless connectors in the clinical environment.

Science.gov (United States)

Slater, Karen; Cooke, Marie; Whitby, Michael; Fullerton, Fiona; Douglas, Joel; Hay, Jennine; Rickard, Claire

2017-08-01

The aim of this study was to quantify culturable microorganisms on needleless connectors (NCs) attached to peripheral intravenous catheters in hospitalized adult medical patients. Half (50%) of 40 NCs were contaminated with microorganisms commonly found on the skin or mouth. Staphylococcus capitis and Staphylococcus epidermidis were most commonly isolated. Emergency department insertion and higher patient dependency were statistically associated with positive NC microorganism growth. These results reaffirm the need for NC decontamination prior to access. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Identification and Characterization of Extremophile Microorganisms with Significance to Astrobiology

Science.gov (United States)

Bej, Asim K.

2003-01-01

It is now well recognized that microorganisms thrive in extreme ecological conditions such as geothermal vents, polar region, acid and alkaline lakes, and the cold pressurized depth of the ocean floor of this planet. Morphological, physiological, biochemical and genetic adaptations to extreme environments by these extremophile microorganisms have generated immense interest amongst astrobiologists who increasingly believe in the existence of extraterrestrial life. The evidence collected by NASA's space probe Galileo suggested the presence of liquid water and volcanic activity on Mars and Jupiter's satellite Europa. Volcanic activity provides some of the heat necessary to keep the water on Europa from freezing that could provide important dissolved chemicals needed by living organisms. The possibility of the existence of hypersaline alkaline lakes and evaporites confined within closed volcanic basins and impact craters on Mars, and a layer of liquid water under the ice on Europa provide sufficient 'raison d'etre' to study microorganisms in similar extreme environments on Earth, which could provide us with a model that would help establish the existence of extraterrestrial life on other planetary bodies. The objectives of the summer research project were as follows: (1) application of molecular approaches to help establish new species of extremophile microorganisms isolated from a hypersaline alkaline lake; and (2) identification of a major cold-shock gene (cspA) homolog from a psychrotolerant microorganism, PmagG1.

Uric acid in plants and microorganisms: Biological applications and genetics - A review.

Science.gov (United States)

Hafez, Rehab M; Abdel-Rahman, Tahany M; Naguib, Rasha M

2017-09-01

Uric acid increased accumulation and/or reduced excretion in human bodies is closely related to pathogenesis of gout and hyperuricemia. It is highly affected by the high intake of food rich in purine. Uric acid is present in both higher plants and microorganisms with species dependent concentration. Urate-degrading enzymes are found both in plants and microorganisms but the mechanisms by which plant degrade uric acid was found to be different among them. Higher plants produce various metabolites which could inhibit xanthine oxidase and xanthine oxidoreductase, so prohibit the oxidation of hypoxanthine to xanthine then to uric acid in the purine metabolism. However, microorganisms produce group of degrading enzymes uricase, allantoinase, allantoicase and urease, which catalyze the degradation of uric acid to the ammonia. In humans, researchers found that several mutations caused a pseudogenization (silencing) of the uricase gene in ancestral apes which exist as an insoluble crystalloid in peroxisomes. This is in contrast to microorganisms in which uricases are soluble and exist either in cytoplasm or peroxisomes. Moreover, many recombinant uricases with higher activity than the wild type uricases could be induced successfully in many microorganisms. The present review deals with the occurrence of uric acid in plants and other organisms specially microorganisms in addition to the mechanisms by which plant extracts, metabolites and enzymes could reduce uric acid in blood. The genetic and genes encoding for uric acid in plants and microorganisms are also presented.

Uric acid in plants and microorganisms: Biological applications and genetics - A review

Directory of Open Access Journals (Sweden)

Rehab M. Hafez

2017-09-01

Full Text Available Uric acid increased accumulation and/or reduced excretion in human bodies is closely related to pathogenesis of gout and hyperuricemia. It is highly affected by the high intake of food rich in purine. Uric acid is present in both higher plants and microorganisms with species dependent concentration. Urate-degrading enzymes are found both in plants and microorganisms but the mechanisms by which plant degrade uric acid was found to be different among them. Higher plants produce various metabolites which could inhibit xanthine oxidase and xanthine oxidoreductase, so prohibit the oxidation of hypoxanthine to xanthine then to uric acid in the purine metabolism. However, microorganisms produce group of degrading enzymes uricase, allantoinase, allantoicase and urease, which catalyze the degradation of uric acid to the ammonia. In humans, researchers found that several mutations caused a pseudogenization (silencing of the uricase gene in ancestral apes which exist as an insoluble crystalloid in peroxisomes. This is in contrast to microorganisms in which uricases are soluble and exist either in cytoplasm or peroxisomes. Moreover, many recombinant uricases with higher activity than the wild type uricases could be induced successfully in many microorganisms. The present review deals with the occurrence of uric acid in plants and other organisms specially microorganisms in addition to the mechanisms by which plant extracts, metabolites and enzymes could reduce uric acid in blood. The genetic and genes encoding for uric acid in plants and microorganisms are also presented.

The useful micro-organism

International Nuclear Information System (INIS)

1970-01-01

Can man survive civilization? Academician Ivan Malek, Director of the Institute of Microbiology in Prague, a member of the Agency's Scientific Advisory Committee and for many years an adviser to the Food and Agriculture Organization, the World Health Organization and UNESCO, believes he can, But he also considers that if man is to survive he must study and use all the resources at his disposal - including the micro-organisms of the planet earth. (author)

Stethoscopes as potential intrahospital carriers of pathogenic microorganisms.

Science.gov (United States)

Campos-Murguía, Alejandro; León-Lara, Ximena; Muñoz, Juan M; Macías, Alejandro E; Alvarez, José A

2014-01-01

Stethoscopes can take part in the transmission of health care-associated infections. We cultured 112 stethoscopes by direct imprint on blood agar to estimate the prevalence of potentially pathogenic microorganisms. Forty-eight (47%) produced 50 potentially pathogenic microorganisms; from these, 43 (86%) were Staphylococcus aureus, of which 18 (42%) were methicillin-resistant S. aureus. We concluded that stethoscopes should be considered as potential fomites and must be disinfected routinely before and after each patient contact. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes

Directory of Open Access Journals (Sweden)

Andrade Carolina M.M.C.

1999-01-01

Full Text Available Thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. Several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. The purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oC to 100°C and to indicate potential opportunities for useful applications derived from these features.

DEVELOPMENT OF MICROORGANISMS FOR CELLULOSE-BIOFUEL CONSOLIDATED BIOPROCESSINGS: METABOLIC ENGINEERS' TRICKS

Directory of Open Access Journals (Sweden)

Roberto Mazzoli

2012-10-01

By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

ROOT CANAL MICROORGANISMS PROFILES O F UPPER ANTERIOR TEETH WITH APICAL PERIODONTITIS

OpenAIRE

Tanumihardja, Maria; Riewpassa, Irene E; Mansjurnasir; Burhanuddin, DP

2013-01-01

Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance. This study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and ch ronic api...

Marine microorganisms. Umi no biseibutsu

Energy Technology Data Exchange (ETDEWEB)

Shimizu, U. (Hiroshima University, Hiroshima (Japan). Faculty of Applied Biological Science)

1992-11-10

This paper explains properties, interactions, and activities of marine microorganisms. Marine bacteria include bacteria of vibrio family of arteromonas genus, luminous bacteria, and aerobic photosynthetic bacteria. Majority of marine bacteria is halophilic, and many proliferate at 5[degree]C or lower. Some of them can proliferate at 20[degree]C to 30[degree]C, or as high temperature as 80[degree]C and higher. Spongiaria and tumicata have many symbiotic microorganisms, and genes equivalent to luminous bacteria genes were discovered in DNA of light emitting organs in luminous fishes. It was verified that animal groups in upwelling zones are supported by bacteria that assimilate inorganics supplied from ocean bottoms. Marine bacteria decompose almost all of organics brought in from land to sea, and those produced in sea. Marine bacteria engage in complex interrelations with other organisms for competition, antagonism, parasitism, and symbiosis. The bacteria make antibacterial substances, anti-algae bacteria, enzyme inhibitors, toxins, pharmacologically active substances, and such physiologically active substances as deposition promoting substances to undersea structures including shells and barnacles, and deposition blocking substances. 53 refs., 3 figs.

Assessing the transport and fate of bioengineered microorganisms in the environment

International Nuclear Information System (INIS)

Barnthouse, L.W.; Palumbo, A.V.

1985-01-01

We review the methods currently available for quantifying the transport and fate of microbes in atmospheric and aqueous media and assess their adequacy for purposes of risk assessment. We review the literature on transport and fate of microorganisms, including studies of: (1) pathways of migration, (2) the survival of microorganisms during transport and fate. In addition, we review the transport and fate models that have been used in environmental risk assessments for radionuclides and toxic chemicals and evaluate their applicability to the problem of assessing environmental risks of bioengineered microorganisms

The Interaction between Multimedia Data Analysis and Theory Development in Design Research

Science.gov (United States)

van Nes, Fenna; Doorman, Michiel

2010-01-01

Mathematics education researchers conducting instruction experiments using a design research methodology are challenged with the analysis of often complex and large amounts of qualitative data. In this paper, we present two case studies that show how multimedia analysis software can greatly support video data analysis and theory development in…

In vivo investigations of genetically modified microorganisms using germ-free rats

DEFF Research Database (Denmark)

Lund jacobsen, Bodil

Risk evaluation of genetically modified microorganism (GMMO) in relation to human health effects brings into consideration the ability of the microorganism to survive and colonise the gastrointestinal tract and the potential gene transfer to the resident microbiota. Different biological containment...

Monitoring of psychrotrophic microorganisms in raw milk

Directory of Open Access Journals (Sweden)

Radka Burdychová

2008-01-01

Full Text Available The group of psychrotrophic microorganisms belongs to the microorganisms representing a risk for human health as well as a risk of milk and milk products spoilage. Some genus are considered to be significant producers of proteolytic and lipolytic enzymes. In this work, we analysed raw milk samples (n = 109 originated from 26 different suppliers from the area of North and Middle Moravia. The screening was performed from March 2007 to February 2008. The total bacterial counts (TBC ranged between 3.2 × 103 to 8.3 × 106 CFU/ml. The psychrotrophic bacterial counts (PBC ranged between 1.0 × 103 to 8.2 × 106 CFU/ml. Total of 48.62 % and 48.62 % of samples exceeded the hygienic limit in raw milk for TBC and PBC, respectively. The correlation between TBC and PBC was highly significant (r = 0.87.Significantly higher (P < 0.05 numbers of psychrotrophic microorganisms were detected in summer months. The identification of isolates was carried out and all strains were sreened for ability to produce proteolytic and lipolytic enzymes. The most commonly identified genus in raw milk was of the genus Pseudomonas. The ability to produce proteases or lipases was found at 76 % identified bacterial strains.

Selection of mesophilic microorganisms with biodesulfuration capacity

International Nuclear Information System (INIS)

Madero, A; Mogollon, L. I; Mora, A.L; Osorio, L.F

1998-01-01

The development of bio desulfurization (BDS) processes for hydrocarbons requires fast and reliable methods for the screening of microorganisms. This work shows the results of the screening process for indigenous Colombian strains with a BDS potential capacity. The main criteria for the screening were the qualitative and quantitative determination of 2-hydroxybiphenyl (2-HBP) as the typical metabolite of the 4S specific pathway. Microorganisms were cultured by two methodologies, A and B, using DBT as the model compound. The quantitative determination of metabolites was made by HPLC. Thirteen strains were evaluated, including the strain Rhodococcus rhodocrous IGTS8, by methods A and B. In method A, the inoculum was exposed to DBT since the beginning of the culture. Method B, employed two stages: (i) Growth period under limiting sulfur conditions, (ii) Transforming period, in which the pre-grown inoculum was exposed to the organic sulfur substrate. The culture of mesophilic microorganisms isolated by method B, served to find a mechanism for the organic sulfur metabolism, and the evaluation of the sulfur removal capability of five indigenous strains. In the cultures of these strains, 2- hydroxybiphenyl (2-HBP) was detected as a byproduct of DBT metabolism, both qualitatively and quantitatively

[Succession of chitinolytic microorganisms in chernozem soil].

Science.gov (United States)

Manucharova, N A; Belova, E V; Vorob'ev, A V; Polianskaia, L M; Stepanov, A L

2005-01-01

The chitinolytic prokaryotic and eukaryotic microbial complex of chernozem soil has been investigated in the course of a succession initiated by the introduction of chitin and humidification. The dynamics of the cell numbers of chitinolytic microorganisms and of their biomass was assessed by fluorescent microscopy and by inoculation of selective media. Emission of carbon dioxide and nitrous oxide, as well as dinitrogen fixation, was assessed by gas chromatography. It was found that, when the succession was initiated by the introduction of both chitin and humidification, it resulted in greater cell numbers and biomass of chitinolytic microorganisms and higher levels of CO2 and N2O emission and of nitrogen fixation than when the succession was initiated by humidification alone. As compared to the control samples, a significant (twofold) increase in the prokaryote cell number and biomass was found on the fourth day of the succession initiated by humidification and introduction of chitin. One week after the initiation of succession, the fungal biomass and length of mycelium were twice as high as those in the control samples. These results led to the conclusion that chitin utilization in chernozem soil starts during the initial stages of succession and is performed by both prokaryotic and eukaryotic microorganisms.

Design of analog networks in the control theory formulation. Part 2: Numerical results

OpenAIRE

Zemliak, A. M.

2005-01-01

The paper presents numerical results of design of nonlinear electronic networks based on the problem formulation in terms of the control theory. Several examples illustrate the prospects of the approach suggested in the first part of the work.

On the application of motivation theory to human factors/ergonomics: motivational design principles for human-technology interaction.

Science.gov (United States)

Szalma, James L

2014-12-01

Motivation is a driving force in human-technology interaction. This paper represents an effort to (a) describe a theoretical model of motivation in human technology interaction, (b) provide design principles and guidelines based on this theory, and (c) describe a sequence of steps for the. evaluation of motivational factors in human-technology interaction. Motivation theory has been relatively neglected in human factors/ergonomics (HF/E). In both research and practice, the (implicit) assumption has been that the operator is already motivated or that motivation is an organizational concern and beyond the purview of HF/E. However, technology can induce task-related boredom (e.g., automation) that can be stressful and also increase system vulnerability to performance failures. A theoretical model of motivation in human-technology interaction is proposed, based on extension of the self-determination theory of motivation to HF/E. This model provides the basis for both future research and for development of practical recommendations for design. General principles and guidelines for motivational design are described as well as a sequence of steps for the design process. Human motivation is an important concern for HF/E research and practice. Procedures in the design of both simple and complex technologies can, and should, include the evaluation of motivational characteristics of the task, interface, or system. In addition, researchers should investigate these factors in specific human-technology domains. The theory, principles, and guidelines described here can be incorporated into existing techniques for task analysis and for interface and system design.

Preparation of microorganism free carrier for biofertilizer product

International Nuclear Information System (INIS)

Latiffah Norddin; Maizatul Akmam Mhd Nasir; Phua Choo Kwai Hoe

2007-01-01

Biofertilizer has been identified as an alternative or complementary to chemical fertilizer to increase soil fertility and crop production in sustainable farming. Biofertilizers are products containing living cells of different types of known microorganisms that may increase crop productivity through N2 fixation, phosphate solubilization or stimulation of plant growth by synthesising phytohormones. A good biofertilizer product needs a good carrier or substrate. A good carrier is free from microbial contamination and can optimise the growth of the biofertilizer microorganisms. Compost is commonly used as carrier or substrate for biofertilizer microorganisms. In the present study, compost produced by Nuclear Malaysia using the Natural Farming was used as a carrier for the biofertilizer products. Gamma irradiation has been used to produce a ?clean? or sterile carrier. The sterilization effect of the carrier was checked by using serial dilution technique. Carriers that were irradiated at 50 kGy of gamma irradiation were found to be sterile. The shelf life of the sterile carriers was also determined. After six months the compost carriers were still free from microbial contamination. (Author)

Selection of potential microorganism for sago starch fermentation

Directory of Open Access Journals (Sweden)

RUTH MELLIAWATI

2006-02-01

Full Text Available Fermentation process of sago starch for the production of bioproduct requires potential microorganism that have ability to hydrolyze sago starch. The purpose of this research was to get the potential of amylolytic microorganisms for their capability of amyloglucosidase activity and to know the sugar strains of the fermentation result. Eleven amylolytic microorganisms (9 strains of mold and 2 strains of yeast were obtained from the collection Research Centre for Biotechnology – Indonesian Institute of Sciences (LIPI, Cibinong-Bogor were used. The selection step was carried out based on their capability of starch hydrolysis to reducing sugar. The best result indicates that the production of reducing sugar reached the highest 18.485 ppm and amyloglucosidase activities was 3.583 units by KTU-1 strain. The highest total acid obtained was 5.85 mg/mL by Rhizopus IFO.R5442. The cell biomass was obtained between 0.5 to 1.74 g dry weight/100 mL and pH of the final fermentation (72 h were 3.57 to 8.38.

Lignite microorganisms

Energy Technology Data Exchange (ETDEWEB)

Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

2007-03-15

The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia.

Science.gov (United States)

Avellaneda-Torres, Lizeth Manuela; Pulido, Claudia Patricia Guevara; Rojas, Esperanza Torres

2014-01-01

A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS) of ribosomal DNA for fungi. Multivariate statistical analysis (MVA) was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

Directory of Open Access Journals (Sweden)

Lizeth Manuela Avellaneda-Torres

2014-12-01

Full Text Available A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP, Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS of ribosomal DNA for fungi. Multivariate statistical analysis (MVA was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

IgG antibodies against microorganisms and atopic disease in Danish adults

DEFF Research Database (Denmark)

Linneberg, Allan; Ostergaard, Christian; Tvede, Michael

2003-01-01

BACKGROUND: Seropositivity to food-borne and orofecal microorganisms (hepatitis A virus, Helicobacter pylori, and Toxoplasma gondii ), which are considered to be markers of poor hygiene, has been reported to be associated with a lower prevalence of atopy. In contrast, colonization of the gut...... with Clostridium difficile, a potential intestinal bacterial pathogen, in early childhood may be associated with a higher prevalence of atopy. OBJECTIVE: The objective of this study was to investigate the association between atopy and exposure to 2 groups of food-borne and orofecal microorganisms: (1) markers...... to microorganisms was assessed as IgG seropositivity to microorganisms. RESULTS: Seropositivity to 2 or 3 markers of poor hygiene (hepatitis A virus, H pylori, and T gondii ) was associated with a lower prevalence of atopy (adjusted odds ratio, 0.5; 95% CI, 0.3 to 0.8). In contrast, seropositivity to 2 or 3...

Using natural biomass microorganisms for drinking water denitrification.

Science.gov (United States)

Costa, Darleila Damasceno; Gomes, Anderson Albino; Fernandes, Mylena; Lopes da Costa Bortoluzzi, Roseli; Magalhães, Maria de Lourdes Borba; Skoronski, Everton

2018-07-01

Among the methods that are studied to eliminate nitrate from drinking water, biological denitrification is an attractive strategy. Although several studies report the use of denitrifying bacteria for nitrate removal, they usually involve the use of sewage sludge as biomass to obtain the microbiota. In the present study, denitrifying bacteria was isolated from bamboo, and variable parameters were controlled focusing on optimal bacterial performance followed by physicochemical analysis of water adequacy. In this way, bamboo was used as a source of denitrifying microorganisms, using either Immobilized Microorganisms (IM) or Suspended Microorganisms (SM) for nitrate removal. Denitrification parameters optimization was carried out by analysis of denitrification at different pH values, temperature, nitrate concentrations, carbon sources as well as different C/N ratios. In addition, operational stability and denitrification kinetics were evaluated. Microorganisms present in the biomass responsible for denitrification were identified as Proteus mirabilis. The denitrified water was submitted to physicochemical treatment such as coagulation and flocculation to adjust to the parameters of color and turbidity to drinking water standards. Denitrification using IM occurred with 73% efficiency in the absence of an external carbon source. The use of SM provided superior denitrification efficiency using ethanol (96.46%), glucose (98.58%) or glycerol (98.5%) as carbon source. The evaluation of the operational stability allowed 12 cycles of biomass reuse using the IM and 9 cycles using the SM. After physical-chemical treatment, only SM denitrified water remained within drinking water standards parameters of color and turbidity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Theory of the optimal design of straight-axis minimum-B mirror confinement configurations

International Nuclear Information System (INIS)

Hall, L.S.

1982-01-01

The design of modern straight-axis linked-mirror plasma-confinement configurations involves a balance between many competing requirements. The dipole and quadrupole components of magnetic induction required in one confinement region often do not match onto the fields of an adjacent region without complications that seriously affect particle drifts or confinement stability. Here, the relevant factors are set down together with the techniques for analytical optimization of the design of a general configuration. A general sufficient condition for the stability of an arbitrary guiding-center MHD equilibrium is derived. This condition makes explicit the stabilizing qualities of good normal curvature and diamagnetic axial current. The instability drive depends on two terms: one carries the sign of normal curvature and the other relates to the relative signs of geodeics curvature and geodesic torsion. The theory is applied to low-beta, large-aspect-ratio equilibria for which analytic expressions for the confining magnetic fields are known. Two optimizations are required to specify the arbitrary features of the quadrupole and dipole fields. One optimization is nonlinear and can be performed by the ordinary calculus of variations; the second optimization is linear and subject to the rules of game theory. Appropriate quality factors are obtained, thus giving the designer quantitative measures with which to balance design trade-offs

Isolation of microorganisms for biological control the moniliophthora roreri

OpenAIRE

suarez contreras, liliana yanet; Rangel Riaño, Alba Luz

2014-01-01

Moniliophlhora roreri is the causal agent of cocoa Moniliasis, which produces losses of up to 60% of the crop, as it affects only its commercial product, the cob. Biological control appears as an alternative management, using endophytic microorganisms. The reason because of this research came up was that it was aimed to isolate microorganisms with antagonist potential for biological control towards the phytopathogen M. roreri in Norte de Santander. This is done through isolation and identifica...

2.3. Global-scale atmospheric dispersion of microorganisms

Science.gov (United States)

Griffin, Dale W.; Gonzalez-Martin, Cristina; Hoose, C.; Smith, D.J.; Delort, Anne-Marie; Amato, Pierre

2018-01-01

This chapter addresses long-range dispersion and the survival of microorganisms across a wide range of altitudes in Earth's atmosphere. Topics include mechanisms of dispersion, survivability of microorganisms known to be associated with long-range transport, natural and artificial sources of bioaerosols, residence time estimation through the use of proxy aerosols, transport and emission models, and monitoring assays (both culture and molecular based). We conclude with a discussion of the known limits for Earth's biosphere boundary, relating aerobiology studies to planetary exploration given the large degree of overlapping requirements for in situ studies (including low biomass life detection and contamination control).

Screening of biosurfactants from cloud microorganisms

Science.gov (United States)

Sancelme, Martine; Canet, Isabelle; Traikia, Mounir; Uhliarikova, Yveta; Capek, Peter; Matulova, Maria; Delort, Anne-Marie; Amato, Pierre

2015-04-01

The formation of cloud droplets from aerosol particles in the atmosphere is still not well understood and a main source of uncertainties in the climate budget today. One of the principal parameters in these processes is the surface tension of atmospheric particles, which can be strongly affected by trace compounds called surfactants. Within a project devoted to bring information on atmospheric surfactants and their effects on cloud droplet formation, we focused on surfactants produced by microorganisms present in atmospheric waters. From our unique collection of microorganisms, isolated from cloud water collected at the Puy-de-Dôme (France),1 we undertook a screening of this bank for biosurfactant producers. After extraction of the supernatants of the pure cultures, surface tension of crude extracts was determined by the hanging drop technique. Results showed that a wide variety of microorganisms are able to produce biosurfactants, some of them exhibiting strong surfactant properties as the resulting tension surface decreases to values less then 35 mN.m-1. Preliminary analytical characterization of biosurfactants, obtained after isolation from overproducing cultures of Rhodococcus sp. and Pseudomonas sp., allowed us to identify them as belonging to two main classes, namely glycolipids and glycopeptides. 1. Vaïtilingom, M.; Attard, E.; Gaiani, N.; Sancelme, M.; Deguillaume, L.; Flossmann, A. I.; Amato, P.; Delort, A. M. Long-term features of cloud microbiology at the puy de Dôme (France). Atmos. Environ. 2012, 56, 88-100. Acknowledgements: This work is supported by the French-USA ANR SONATA program and the French-Slovakia programs Stefanik and CNRS exchange.

Evaluation of the effect of efficient microorganisms and Trichoderma harzianum application on the production of onion plantlets (Allium cepa L.

Directory of Open Access Journals (Sweden)

Ramón Liriano González

2015-02-01

Full Text Available The research was done in the intensive-farming areas of the Cooperative of Credits and Services “Ramón Ruiz del Sol”, in Los Arabos, Matanzas. The objective was to evaluate the application effects of effective microorganism (EM and Trichoderma harzianum on the main growth indexes of onion seedlings (Allium cepa L. during nursery stage. Six treatments were studied ( control, organic matter at 24 kg.m-2, T. harzianum at 30 g.m-2, Effective Microorganisms at 15 mL.m-2 at the moment of sowing and 15 and 30 days after the germination of the seeds, organic matter at 24 kg.m-2 + T. harzianum 30 g.m-2 + Efficient Microorganisms at 15 mL.m-2 at 15 and 30 days after germination of the seeds, and T. harzianum 30 g.m-2 + Efficient Microorganisms at 15 mL.m-2 at 15 and 30 days after the germination of the seeds. The experiment was arranged in a randomized block design. 55 days after seed germination, the height of the seedlings, number of leaves per seedlings, diameter of the false stem, root length, as well as the fresh and dry weight of the radical system and the foliate area were evaluated. The results proved that the Effective Microorganisms (EM and T. harzianum application improved the production of quality onion seedlings. The treatment 5 (organic matter 24 kg.m-2 + T. harzianum 30 g.m-2 + Efficient Microorganisms at 15 mL.m-2 at 15 and 30 days after germination had better results in the evaluated variables.

Diversity and adaptations of deep-sea microorganisms

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.

-tolerant enzymes, natural products of potential use in human health management and environmental bioremediation using solvent-tolerant microorganisms are some of the potential biotechnological applications of these deep-sea microbes....

DENTINE CARIES: ACID-TOLERANT MICROORGANISMS AND ASPECTS ON COLLAGEN DEGRADATION.

Science.gov (United States)

Lager, Anders Hedenbjörk

2014-01-01

Dental caries is a common disease all over the world, despite the fact that it can be both effectively prevented and treated. It is driven by acids produced by oral microorganisms as a consequence of their metabolism of dietary carbohydrates. Given enough acid challenge, eventually the tooth enamel barrier will be broken down, and the carious lesion will extend into underlying hard tissue, forming a macroscopic cavity in the dentine. In comparison to biofilm on enamel, a dentine carious lesion provides a vastly different environment for the residing microorganisms. The environment influences the types and numbers of microorganisms that can colonize the dentine caries lesion. The overall aims for this thesis are to enumerate and further study microorganisms found in established dentine caries lesions and also to illuminate how host-derived proteolytic enzymes might contribute to this degradation, not only to better understand the caries process in dentine but also to find incitements for new methods to influence the natural progression of caries lesions. In Paper I, the numbers of remaining viable microorganisms after completed excavation using two excavation methods were investigated. Samples of carious dentine tissue were collected before and after excavation and cultivated on different agar media in different atmospheres. Analysis was performed by counting the number of colony-forming units (CFUs). Key findings: The number of remaining microorganisms after excavation was low for both methods, but some microorganisms always remained in the cavity floors even when the cavities were judged as caries free using normal clinical criteria. In Paper II, the acid tolerant microbiota in established dentine caries lesions was investigated. Samples were taken as in Paper I, but on three levels (superficial, center of lesion, floor of lesion after completed excavation). The samples were cultivated in anaerobic conditions on solid pH-selective agar media of different acidity

Modelling the morphology of filamentous microorganisms

DEFF Research Database (Denmark)

Nielsen, Jens Bredal

1996-01-01

The rapid development in image analysis techniques has made it possible to study the growth kinetics of filamentous microorganisms in more detail than previously, However, owing to the many different processes that influence the morphology it is important to apply mathematical models to extract...

Tapping uncultured microorganisms through metagenomics for drug ...

African Journals Online (AJOL)

African Journal of Biotechnology ... Microorganisms are major source of bioactive natural products, and several ... This review highlights the recent methodologies, limitations, and applications of metagenomics for the discovery of new drugs.

Theory and design of an Annual Cycle Energy System (ACES) for residences

Energy Technology Data Exchange (ETDEWEB)

Nephew, E.A.; Abbatiello, L.A.; Ballou, M.L.

1980-05-01

The basic concept of the Annual Cycle Energy System (ACES) - an integrated system for supplying space heating, hot water, and air conditioning to a building - and the theory underlying its design and operation are described. Practical procedures for designing an ACES for a single-family residence, together with recommended guidelines for the construction and installation of system components, are presented. Methods are discussed for estimating the life-cycle cost, component sizes, and annual energy consumption of the system for residential applications in different climatic regions of the US.

A New Approach on Sampling Microorganisms from the Lower Stratosphere

Science.gov (United States)

Gunawan, B.; Lehnen, J. N.; Prince, J.; Bering, E., III; Rodrigues, D.

2017-12-01

University of Houston's Undergraduate Student Instrumentation Project (USIP) astrobiology group will attempt to provide a cross-sectional analysis of microorganisms in the lower stratosphere by collecting living microbial samples using a sterile and lightweight balloon-borne payload. Refer to poster by Dr. Edgar Bering in session ED032. The purpose of this research is two-fold: first, to design a new system that is capable of greater mass air intake, unlike the previous iterations where heavy and power-intensive pumps are used; and second, to provide proof of concept that live samples are accumulated in the upper atmosphere and are viable for extensive studies and consequent examination for their potential weather-altering characteristics. Multiple balloon deployments will be conducted to increase accuracy and to provide larger set of data. This paper will also discuss visual presentation of the payload along with analyzed information of the captured samples. Design details will be presented to NASA investigators for professional studies

Analog Electronic Filters Theory, Design and Synthesis

CERN Document Server

Dimopoulos, Hercules G

2012-01-01

Filters are essential subsystems in a huge variety of electronic systems. Filter applications are innumerable; they are used for noise reduction, demodulation, signal detection, multiplexing, sampling, sound and speech processing, transmission line equalization and image processing, to name just a few. In practice, no electronic system can exist without filters. They can be found in everything from power supplies to mobile phones and hard disk drives and from loudspeakers and MP3 players to home cinema systems and broadband Internet connections. This textbook introduces basic concepts and methods and the associated mathematical and computational tools employed in electronic filter theory, synthesis and design.  This book can be used as an integral part of undergraduate courses on analog electronic filters. Includes numerous, solved examples, applied examples and exercises for each chapter. Includes detailed coverage of active and passive filters in an independent but correlated manner. Emphasizes real filter...

Detection of extracellular enzymatic activity in microorganisms ...

African Journals Online (AJOL)

Detection of extracellular enzymatic activity in microorganisms isolated from waste vegetable oil contaminated soil using plate methodologies. Eugenia G. Ortiz Lechuga, Isela Quintero Zapata, Katiushka Arévalo Niño ...

Detection of extracellular enzymatic activity in microorganisms ...

African Journals Online (AJOL)

sunny t

2015-09-18

Sep 18, 2015 ... microorganisms with all three enzymatic activities, thereby establishing these techniques as ... supplemented at 1% with vegetable oils, including olive (OLI) ..... cepacia lipase for biodiesel fuel production from soybean oil.

Cognitive Load Theory, Educational Research, and Instructional Design: Some Food for Thought

Science.gov (United States)

de Jong, Ton

2010-01-01

Cognitive load is a theoretical notion with an increasingly central role in the educational research literature. The basic idea of cognitive load theory is that cognitive capacity in working memory is limited, so that if a learning task requires too much capacity, learning will be hampered. The recommended remedy is to design instructional systems…

New detection systems of bacteria using highly selective media designed by SMART: selective medium-design algorithm restricted by two constraints.

Directory of Open Access Journals (Sweden)

Takeshi Kawanishi

Full Text Available Culturing is an indispensable technique in microbiological research, and culturing with selective media has played a crucial role in the detection of pathogenic microorganisms and the isolation of commercially useful microorganisms from environmental samples. Although numerous selective media have been developed in empirical studies, unintended microorganisms often grow on such media probably due to the enormous numbers of microorganisms in the environment. Here, we present a novel strategy for designing highly selective media based on two selective agents, a carbon source and antimicrobials. We named our strategy SMART for highly Selective Medium-design Algorithm Restricted by Two constraints. To test whether the SMART method is applicable to a wide range of microorganisms, we developed selective media for Burkholderia glumae, Acidovorax avenae, Pectobacterium carotovorum, Ralstonia solanacearum, and Xanthomonas campestris. The series of media developed by SMART specifically allowed growth of the targeted bacteria. Because these selective media exhibited high specificity for growth of the target bacteria compared to established selective media, we applied three notable detection technologies: paper-based, flow cytometry-based, and color change-based detection systems for target bacteria species. SMART facilitates not only the development of novel techniques for detecting specific bacteria, but also our understanding of the ecology and epidemiology of the targeted bacteria.

Ultra-violet radiation for the inactivation of microorganisms in hydroponics

International Nuclear Information System (INIS)

Buyanosvsky, G.; Gale, J.; Degani, N.

1981-01-01

The growth of microorganisms in the nutrient solution of a circulating hydroponic system was suppressed by ultra-violet radiation. Applied for three hours daily (572 Jm -2 h -1 ) throughout experiments in which tomato and corn were grown, it was effective in reducing the population of microorganisms from between 500-800 x 10 3 to 10-50 x 10 3 cells per ml. (orig.)

Ultra-violet radiation for the inactivation of microorganisms in hydroponics

Energy Technology Data Exchange (ETDEWEB)

Buyanosvsky, G; Gale, J [Ben-Gurion Univ. of the Negev, Beersheva (Israel). Jacob Blaustein Inst. for Desert Research; Degani, N [Israel Atomic Energy Commission, Beersheba. Nuclear Research Center-Negev

1981-01-01

The growth of microorganisms in the nutrient solution of a circulating hydroponic system was suppressed by ultra-violet radiation. Applied for three hours daily (572 Jm/sup -2/h/sup -1/) throughout experiments in which tomato and corn were grown, it was effective in reducing the population of microorganisms from between 500-800 x 10/sup 3/ to 10-50 x 10/sup 3/ cells per ml.

Coal Enrichment Methods by Using Microorganisms and Their Metabolites

Directory of Open Access Journals (Sweden)

Małgorzata Deska

2018-03-01

Full Text Available The aim of this study is to review the literature on the methods of low-rank coal enrichment by using microorganisms and their metabolites. Effective bio-beneficiation technologies for low-rank coals in the future are also suggested throughout this paper. An extensive literature review highlights recent advances in bio-beneficiation technologies for low rank coals. This paper presents the state of the art in the field of the bio-beneficiation technology - carbon leaching with the aid of microorganisms, especially fungi. The knowledge of the low-rank coals leaching is an important step to meet the carbon eco-requirements and improve the economics of mining companies. There are several reasons to investigate microbial activities towards coal. This paper presents the current state of knowledge concerning bioleaching of coal. Thus, in view of the increasing importance of hard coal as a raw material and energy source, it seems hopeful to study the potential of microorganisms to modify the low-rank coal structure.

Genetic fingerprint of microorganisms associated with the ...

Indian Academy of Sciences (India)

inviting range of elements which microorganisms use in their ... ization and degradation of organic binders leading to struc- tural damage (Herrera et al. 2004). Microbial solubilization of materials involves the produc- ... architectural cement.

Crowd-Designed Motivation: Motivational Messages for Exercise Adherence Based on Behavior Change Theory

NARCIS (Netherlands)

de Vries, R.A.J.; Truong, Khiet Phuong; Kwint, Sigrid; Drossaert, Constance H.C.; Evers, Vanessa

2016-01-01

Developing motivational technology to support long-term behavior change is a challenge. A solution is to incorporate insights from behavior change theory and design technology to tailor to individual users. We carried out two studies to investigate whether the processes of change, from the

Antimicrobial activity of different disinfectants against cariogenic microorganisms

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Esra UZER CELIK

Full Text Available Abstract The aim of this study was to assess the in vitro antimicrobial effects of chlorhexidine digluconate (CHX, polyhexamethylene biguanide (PHBM, and octenidine dihydrochloride (OCT on cariogenic microorganisms by using their minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC. CHX, PHBM, and OCT were diluted in distilled water to the final test concentrations. Using the in-tube dilution method, Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces viscosus were cultivated on blood agar and Mueller–Hinton broth (MHB at 37°C for 48 h. They were read using a spectrophotometer to detect MIC. To determine MBC, samples in the range of the turbidity threshold after 24 h were transferred onto blood agar and evaluated for growth after 24 h. Different MICs and MBCs were observed in all disinfectants against each microorganism. The lowest MIC and MBC against S. mutans (60 mg/L were obtained from PHBM. The lowest values against L. rhamnosus (15 mg/L, 30 mg/L, A. viscosus (30 mg/L, and L. acidophilus (15 mg/L, 30 mg/L were determined by OCT. PHBM and OCT have the potential to be replaced with CHX because they were effective against cariogenic microorganisms.

Photocatalytic treatment of bioaerosols: impact of the reactor design.

Science.gov (United States)

Josset, Sébastien; Taranto, Jérôme; Keller, Nicolas; Keller, Valérie; Lett, Marie-Claire

2010-04-01

Comparing the UV-A photocatalytic treatment of bioaerosols contaminated with different airborne microorganisms such as L. pneumophila bacteria, T2 bacteriophage viruses and B. atrophaeus bacterial spores, pointed out a decontamination sensitivity following the bacteria > virus > bacterial spore ranking order, differing from that obtained for liquid-phase or surface UV-A photocatalytic disinfection. First-principles CFD investigation applied to a model annular photoreactor evidenced that larger the microorganism size, higher the hit probability with the photocatalytic surfaces. Applied to a commercial photocatalytic purifier case-study, the CFD calculations showed that the performances of the studied purifier could strongly benefit from rational reactor design engineering. The results obtained highlighted the required necessity to specifically investigate the removal of airborne microorganisms in terms of reactor design, and not to simply transpose the results obtained from studies performed toward chemical pollutants, especially for a successful commercial implementation of air decontamination photoreactors. This illustrated the importance of the aerodynamics in air decontamination, directly resulting from the microorganism morphology.

Designing “Theory of Machines and Mechanisms” course on Project Based Learning approach

DEFF Research Database (Denmark)

Shinde, Vikas

2013-01-01

by the industry and the learning outcomes specified by the National Board of Accreditation (NBA), India; this course is restructured on Project Based Learning approach. A mini project is designed to suit course objectives. An objective of this paper is to discuss the rationale of this course design......Theory of Machines and Mechanisms course is one of the essential courses of Mechanical Engineering undergraduate curriculum practiced at Indian Institute. Previously, this course was taught by traditional instruction based pedagogy. In order to achieve profession specific skills demanded...... and the process followed to design a project which meets diverse objectives....

Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

International Nuclear Information System (INIS)

Gonzalez-Barreiro, O.; Rioboo, C.; Herrero, C.; Cid, A.

2006-01-01

The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides

Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Barreiro, O. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Rioboo, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Herrero, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Cid, A. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain)]. E-mail: cid@udc.es

2006-11-15

The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides.

Integrating psychological theory into the design of an online intervention for sexual health: the sexunzipped website.

Science.gov (United States)

Carswell, Kenneth; McCarthy, Ona; Murray, Elizabeth; Bailey, Julia V

2012-11-19

The Internet can provide a confidential and convenient medium for sexual health promotion for young people. This paper describes the development of an interactive, theory-based website (Sexunzipped) aimed at increasing safe sexual behavior of young people, as well as an outline of the evaluation protocol. The website focuses on safer sex, relationships, and sexual pleasure. An overview of the site is provided, including a description of the theoretical constructs which form the basis of the site development. An integrated behavioral model was chosen as the guiding theory for the Sexunzipped intervention. A randomized trial design will be used to evaluate the site quantitatively. The content of the site is described in detail with examples of the main content types: information pages, quizzes, and decision-making activities. We describe the protocol for quantitative evaluation of the website using a randomized trial design and discuss the principal challenges involved in developing the site, including the challenge of balancing the requirements of theory with young people's views on website content and design. Considerations for future interventions are discussed. Developing an online behavior-change intervention is costly and time consuming. Given the large public health potential, the cost involved in developing online interventions, and the need for attractive design, future interventions may benefit from collaborating with established sites that already have a user base, a brand, and a strong Internet presence. It is vital to involve users in decisions about intervention content, design, and features, paying attention to aspects that will attract and retain users' interest. A central challenge in developing effective Internet-based interventions for young people is to find effective ways to operationalize theory in ways that address the views and perspectives of young people.

Collective Motion of Micro-organisms from Field Theoretical Viewpoint

OpenAIRE

Nojiri, Shin'ichi; Kawamura, Masako; Sugamoto, Akio

1995-01-01

We analyze the collective motion of micro-organisms in the fluid and consider the problem of the red tide. The red tide is produced by the condensation of the micro-organisms, which might be a similar phenomenon to the condensation of the strings. We propose a model of the generation of the red tide. By considering the interaction between the micro- organisms mediated by the velocity fields in the fluid, we derive the Van der Waals type equation of state, where the generation of the red tide ...

THE ASPECTS OF INVESTIGATION OF MICROORGANISM ANTIBIOTIC RESISTANCE AT THE PRESENT STAGE

Directory of Open Access Journals (Sweden)

Andreeva I.A.

2015-05-01

Full Text Available Introduction. At the present stage for ensuring epidemic safety and prevention of nosocomial infections the complex of analytical study and managerial procedure to improve the epidemiological supervision over nosocomial infections through the introduction of infection control in health care practice are using. The microbiological monitoring is part of the infectious control and allows supervising circulation of microorganisms and their antimicrobial resistance by dynamic observation over structure and level of resistance to antibiotics that are used in the given particular hospital. Materials and methods. For the dynamic observation of the structure and the level of resistance of microorganisms to antimicrobial agents the computer software WHONET recommended by WHO has been used. With using WHONET in Dnepropetrovsk Children's Hospital № 3 the computer database has been created. In this database the information about each patient, hospital department, samples under test and the date of its excretion, the data about the detected microorganism and its sensitivity/resistance to antimicrobial agents have been stored. The examination and analysis of antibiotic resistance of microorganisms has been provided for 2010- 2014 years, in total the data on 6168 isolates from 3876 patients have been analyzed. Results and discussion. By the total data the isolates belong to a wide spectrum of microorganisms (more than 40 different types. By means of the analysis of isolating of clinically significant microorganisms it has been established that one of the most frequent isolated were Escherichia coli (1-20 %, Klebsiella pneumoniae (4-18 %, Staphylococcus epidermidis (1-12 %, S. aureus (1-10 %, Enterobacter cloacae (2-9 %, Pseudomonas aeruginosa (1-8 %. Detection of other microorganisms was irregular and its frequency is varied from 0 % to 10 %. As a result of examining the sensitivity of microorganisms it has been shown that tested strains of bacteria were

Studies on the radiation sensitivity of food microorganism by high dose irradiation

International Nuclear Information System (INIS)

Hwang, Han Joon; Lee, Eun Jung; Yu, Hyun Hee; Lee, Jae Ho

2010-04-01

We investigated the radio resistance of pathogenic microorganisms (Bacillus cereus, Staphylococcus aureus, Methicillin resistant Staphylococcus aureus(MRSA) and Escherichia coli O157) in irradiating environments. Their radiation conditions of pathogenic microorganisms varied with pH(3-10), salt concentration(1-15%), temperature(-20, 4 and 25 .deg. C) and atmospheric condition. In addition, the effect of γ-irradiation on the inactivation of pathogenic microorganisms inoculated into food (saengsik, sliced ham, chopped beef) was investigated. The radiation dose ranged from 0 to 3 kGy. The γ--irradiated B.cereus(γ--BC) St.aureus(γ--SA), MRSA(γ--MRSA) and E.coli O157(γ--EC) were then cultured and the viable cell count on plate count agar and D10-values(dose required to inactivate 90% of a microbial population) were calculated. The number of pathogenic microorganisms at pH(3-10) and salt concentration(1-15%), temperature(-20, 4 and 25 .deg. C) and atmospheric condition decreased by 1 log CFU/ml after irradiation. The D 10 -value of γ--SA in the optimum condition was 0.152 kGy, and these of γ--MRSA and γ--EC were 0.346 and 0.240 kGy, respectively. The initial cell counts of pathogenic microorganisms in culture broth were slightly decreased as the decrease of pH and the increase of salt concentration. However, radiation resistance of pathogenic microorganisms was increased at frozen state. Moreover, D 10 -values of these is test strains in saengsik, sliced ham and chopped beef were 0.597, 0.226 , 0.398 and 0.416 kGy, respectively. These results provide the basic information for the in activation of pathogenic microorganisms in foods by irradiation

Studies on the radiation sensitivity of food microorganism by high dose irradiation

Energy Technology Data Exchange (ETDEWEB)

Hwang, Han Joon; Lee, Eun Jung; Yu, Hyun Hee; Lee, Jae Ho [Korea University, Seoul (Korea, Republic of)

2010-04-15

We investigated the radio resistance of pathogenic microorganisms (Bacillus cereus, Staphylococcus aureus, Methicillin resistant Staphylococcus aureus(MRSA) and Escherichia coli O157) in irradiating environments. Their radiation conditions of pathogenic microorganisms varied with pH(3-10), salt concentration(1-15%), temperature(-20, 4 and 25 .deg. C) and atmospheric condition. In addition, the effect of {gamma}-irradiation on the inactivation of pathogenic microorganisms inoculated into food (saengsik, sliced ham, chopped beef) was investigated. The radiation dose ranged from 0 to 3 kGy. The {gamma}--irradiated B.cereus({gamma}--BC) St.aureus({gamma}--SA), MRSA({gamma}--MRSA) and E.coli O157({gamma}--EC) were then cultured and the viable cell count on plate count agar and D10-values(dose required to inactivate 90% of a microbial population) were calculated. The number of pathogenic microorganisms at pH(3-10) and salt concentration(1-15%), temperature(-20, 4 and 25 .deg. C) and atmospheric condition decreased by 1 log CFU/ml after irradiation. The D{sub 10}-value of {gamma}--SA in the optimum condition was 0.152 kGy, and these of {gamma}--MRSA and {gamma}--EC were 0.346 and 0.240 kGy, respectively. The initial cell counts of pathogenic microorganisms in culture broth were slightly decreased as the decrease of pH and the increase of salt concentration. However, radiation resistance of pathogenic microorganisms was increased at frozen state. Moreover, D{sub 10}-values of these is test strains in saengsik, sliced ham and chopped beef were 0.597, 0.226 , 0.398 and 0.416 kGy, respectively. These results provide the basic information for the in activation of pathogenic microorganisms in foods by irradiation

Profiling micro-organic contaminants in groundwater using multi-level piezometers

OpenAIRE

White, Debbie; Lapworth, Dan; Stuart, Marianne; Williams, Peter

2015-01-01

The presence of micro-organic pollutants, including ‘emerging contaminants’ within groundwater is of increasing interest. Robust protocols are required to minimise the introduction of contamination during the sampling process. Below we discuss the sampling protocols used to reduce inputs of plasticisers during the sampling process, as well as the techniques used to characterise the distribution of micro-organic pollutants in the subsurface. In this study multi-level piezometers...

Method for treating wastewater using microorganisms and vascular aquatic plants

Science.gov (United States)

Wolverton, B. C. (Inventor)

1983-01-01

A method for treating wastewater compresses subjecting the wastewater to an anaerobic setting step for at least 6 hours and passing the liquid effluent from the anaerobic settling step through a filter cell in an upflow manner. There the effluent is subjected first to the action of anaerobic and facultative microorganisms, and then to the action of aerobic microorganisms and the roots of at least one vascular aquatic plant.

Ecology and metagenomics of soil microorganisms

Czech Academy of Sciences Publication Activity Database

Baldrian, Petr; Head, I. M.; Prosser, J. I.; Schloter, M.; Smalla, K.; Tebbe, C. C.

2011-01-01

Roč. 78, č. 1 (2011), s. 1-2 ISSN 0168-6496 R&D Projects: GA MŠk LC06066; GA MŠk(CZ) LA10001 Institutional research plan: CEZ:AV0Z50200510 Keywords : microorganism * bioremediation * biogenesis of soil Subject RIV: EE - Microbiology, Virology Impact factor: 3.408, year: 2011

Novel genome alteration system for microorganisms

NARCIS (Netherlands)

Daran, J.G.; Geertman, J.M.; Bolat, I.

2015-01-01

The invention relates to a set of targeting constructs, comprising a first construct comprising a recognition site for an endonuclease, a first region of homology with a target gene of a microorganism, and a first part of a selection marker, and a second construct comprising a second part of the

An empirical test of new developments in coalition theory for the design of international environmental agreements

NARCIS (Netherlands)

Finus, M.; Sáiz Pérez, M.E.; Hendrix, E.M.T.

2009-01-01

We consider new developments in coalition theory for the design of international environmental agreements (IEAs). Applying an empirical model on climate change that comprises benefit and cost estimates from abatement for 12 world regions, we analyze how the design of an agreement affects the success

Potentially pathogenic amoeba-associated microorganisms in cooling towers and their control.

Science.gov (United States)

Pagnier, Isabelle; Merchat, Michèle; La Scola, Bernard

2009-06-01

Cooling towers provide a favorable environment for the proliferation of microorganisms. Cooling towers generate a biofilm and often aerosolize contaminated water, thereby increasing the risk of microorganism dissemination by human inhalation. This pathogen dissemination was first revealed by the epidemics of Legionnaires' disease that were directly related to the presence of cooling towers, and since then, the ecology of Legionella pneumophila has been well studied. Each country has specific standards regarding the acceptable amount of microorganisms in cooling tower systems. However, those standards typically only concern L. pneumophila, even though many other microorganisms can also be isolated from cooling towers, including protozoa, bacteria and viruses. Microbiological control of the cooling tower system can be principally achieved by chemical treatments and also by improving the system's construction. Several new treatments are being studied to improve the efficiency of disinfection. However, as most of these treatments continue to focus solely on L. pneumophila, reports of other types of pathogens continue to increase. Therefore, how their dissemination affects the human populous health should be addressed now.

Root Canal Microorganisms Profiles of Upper Anterior Teeth with Periapical Lesion

Directory of Open Access Journals (Sweden)

Maria Tanumiharja

2014-12-01

Full Text Available Microorganisms are the main causative agents on the development of apical periodontitis. Microorganisms infecting the root canal system are colonized in communities as biofilm. These bacterial communities show distinct pattern related to the different forms of apical periodontitis which are determined by species richness and abundance. Objective: This study is aimed to examine the root canal microorganisms on upper anterior teeth of asymptomatic apical periodontitis and chronic apical abscess. Methods: Samples were collected from patients referring to Endodontic Department of Hasanuddin University Dental Hospital from July 2013 to September 2013. Twenty two samples, aged 17-40 were collected from 16 patients with asymptomatic apical periodontitis, and 36 samples, aged 18-50 were collected from 36 patients with chronic apical abscess. Microorganisms were evaluated using cultural technique. Results: The results showed predominant bacteria in asymptomatic apical periodontitis is Porhyromonas spp while in chronic apical abscess both Streptococcus spp and Porhyromonas spp showed similar frequencies. Conclusion: This study shows Porhyromonas spp play dominant role in apical periodontitis either in asymptomatic apical periodontitis or chronic apical abscess.

Halophilic microorganisms in deteriorated historic buildings: insights into their characteristics.

Science.gov (United States)

Adamiak, Justyna; Otlewska, Anna; Gutarowska, Beata; Pietrzak, Anna

2016-01-01

Historic buildings are constantly being exposed to numerous climatic changes such as damp and rainwater. Water migration into and out of the material's pores can lead to salt precipitation and the so-called efflorescence. The structure of the material may be seriously threatened by salt crystallization. A huge pressure is produced when salt hydrates occupy larger spaces, which leads at the end to cracking, detachment and material loss. Halophilic microorganisms have the ability to adapt to high salinity because of the mechanisms of inorganic salt (KCl or NaCl) accumulation in their cells at concentrations isotonic to the environment, or compatible solutes uptake or synthesis. In this study, we focused our attention on the determination of optimal growth conditions of halophilic microorganisms isolated from historical buildings in terms of salinity, pH and temperature ranges, as well as biochemical properties and antagonistic abilities. Halophilic microorganisms studied in this paper could be categorized as a halotolerant group, as they grow in the absence of NaCl, as well as tolerate higher salt concentrations (Staphylococcus succinus, Virgibacillus halodenitrificans). Halophilic microorganisms have been also observed (Halobacillus styriensis, H. hunanensis, H. naozhouensis, H. litoralis, Marinococcus halophilus and yeast Sterigmatomyces halophilus). With respect to their physiological characteristics, cultivation at a temperature of 25-30°C, pH 6-7, NaCl concentration for halotolerant and halophilic microorganisms, 0-10% and 15-30%, respectively, provides the most convenient conditions. Halophiles described in this study displayed lipolytic, glycolytic and proteolytic activities. Staphylococcus succinus and Marinococcus halophilus showed strong antagonistic potential towards bacteria from the Bacillus genus, while Halobacillus litoralis displayed an inhibiting ability against other halophiles.

Interactions Between Beneficial and Harmful Microorganisms: From the Composting Process to Compost Application

OpenAIRE

Fuchs, Jacques G.

2010-01-01

Numerous microorganisms are involved in the composting process, but their precise roles are often unknown. Compost microorganisms are influenced by the composition of the substrate and by the temperature in the compost pile. In addition, different microorganisms also influence each other, e.g. through competition. In the first phase of composting, microbial activity increase drastically, leading to a rise in temperature. The initial bacterial dominance is replaced by a fungal one during compo...

Production of gaba (γ - aminobutyric acid by microorganisms: a review

Directory of Open Access Journals (Sweden)

Radhika Dhakal

2012-12-01

Full Text Available GABA (γ-aminobutyric acid is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB, which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

Production of gaba (γ - Aminobutyric acid) by microorganisms: a review.

Science.gov (United States)

Dhakal, Radhika; Bajpai, Vivek K; Baek, Kwang-Hyun

2012-10-01

GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB), which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods.

How to develop a theory-driven evaluation design? Lessons learned from an adolescent sexual and reproductive health programme in West Africa.

Science.gov (United States)

Van Belle, Sara B; Marchal, Bruno; Dubourg, Dominique; Kegels, Guy

2010-11-30

This paper presents the development of a study design built on the principles of theory-driven evaluation. The theory-driven evaluation approach was used to evaluate an adolescent sexual and reproductive health intervention in Mali, Burkina Faso and Cameroon to improve continuity of care through the creation of networks of social and health care providers. Based on our experience and the existing literature, we developed a six-step framework for the design of theory-driven evaluations, which we applied in the ex-post evaluation of the networking component of the intervention. The protocol was drafted with the input of the intervention designer. The programme theory, the central element of theory-driven evaluation, was constructed on the basis of semi-structured interviews with designers, implementers and beneficiaries and an analysis of the intervention's logical framework. The six-step framework proved useful as it allowed for a systematic development of the protocol. We describe the challenges at each step. We found that there is little practical guidance in the existing literature, and also a mix up of terminology of theory-driven evaluation approaches. There is a need for empirical methodological development in order to refine the tools to be used in theory driven evaluation. We conclude that ex-post evaluations of programmes can be based on such an approach if the required information on context and mechanisms is collected during the programme.

Design, Implementation, and Lessons Learned from a Digital Storytelling Project in an Undergraduate Health Promotion Theory Course

Science.gov (United States)

Rimando, Marylen; Smalley, K. Bryant; Warren, Jacob C.

2015-01-01

This article describes the design, implementation and lessons learned from a digital storytelling project in a health promotion theory course. From 2011-2012, 195 health promotion majors completed a digital storytelling project at a Midwestern university. The instructor observed students' understanding of theories and models. This article adds to…

Oxybiotest project: microorganisms under pressure. Hyperbaric oxygen (HBO and simple pressure interaction on selected bacteria

Directory of Open Access Journals (Sweden)

Zanon Vincenzo

2012-09-01

Full Text Available Abstract Background HyperBaric Oxygen (HBO therapy involves exposure to pure oxygen in a pressurized room, and it is an already well-established treatment for various conditions, including those originated by serious infections. Starting from the observation of an increased number of patients who were accessing our HBO units for diseases supported from concomitant multidrug-resistant microorganisms, as well as considering the evident clinical benefit and laboratory final outcome of those patients at the end of the treatment, aim of our study was to measure, or better define at least, if there was any interaction between a hyperbaric environment and some selected microorganisms and if those positive results were due to the increased oxygen partial pressure (pO2 value or just to the increased pressure, regardless of the fraction of inspired oxygen (FiO2 applied (21÷100%. Design and methods We applied various increased pO2 values in a hyperbaric environment. Our study design was tailored in four steps to answer four specific questions, ordered in a progressive process: OxyBioTest (OBT-1,2,3, and 4. Specifically, we chose to investigate possible changes in the Minimum Inhibitory Concentration (MIC and in the Minimum Bactericidal Concentration (MBC of multi-resistant microorganisms after a single session of hyperbaric therapy. Results OBT-1 and OBT-2 provide a semi-quantitative confirmation of the bacterio-cidal and cytostatic effects of HBO. HBO is cidal only if the total exposure pressure is elevated, and cidal or cytostatic effect are not always dependent on the pO2 applied. OBT-4 has shown the adjuvant effect of HBO and antimicrobial drug against some selected bacteria. Discussion We seem allowed to hypothesize that only in case of a good approach to a lesion, permitting smaller bacterial loads thanks to surgical debridement and/or eventual antibiotic therapy for example, You can observe the clear effectiveness of the HyperBaric Oxygen (HBO

Aligning Theory and Design: The Development of an Online Learning Intervention to Teach Evidence-based Practice for Maximal Reach.

Science.gov (United States)

Delagran, Louise; Vihstadt, Corrie; Evans, Roni

2015-09-01

Online educational interventions to teach evidence-based practice (EBP) are a promising mechanism for overcoming some of the barriers to incorporating research into practice. However, attention must be paid to aligning strategies with adult learning theories to achieve optimal outcomes. We describe the development of a series of short self-study modules, each covering a small set of learning objectives. Our approach, informed by design-based research (DBR), involved 6 phases: analysis, design, design evaluation, redesign, development/implementation, and evaluation. Participants were faculty and students in 3 health programs at a complementary and integrative educational institution. We chose a reusable learning object approach that allowed us to apply 4 main learning theories: events of instruction, cognitive load, dual processing, and ARCS (attention, relevance, confidence, satisfaction). A formative design evaluation suggested that the identified theories and instructional approaches were likely to facilitate learning and motivation. Summative evaluation was based on a student survey (N=116) that addressed how these theories supported learning. Results suggest that, overall, the selected theories helped students learn. The DBR approach allowed us to evaluate the specific intervention and theories for general applicability. This process also helped us define and document the intervention at a level of detail that covers almost all the proposed Guideline for Reporting Evidence-based practice Educational intervention and Teaching (GREET) items. This thorough description will facilitate the interpretation of future research and implementation of the intervention. Our approach can also serve as a model for others considering online EBP intervention development.

A Compliant Bistable Mechanism Design Incorporating Elastica Buckling Beam Theory and Pseudo-Rigid-Body Model

DEFF Research Database (Denmark)

Sönmez, Ümit; Tutum, Cem Celal

2008-01-01

In this work, a new compliant bistable mechanism design is introduced. The combined use of pseudo-rigid-body model (PRBM) and the Elastica buckling theory is presented for the first time to analyze the new design. This mechanism consists of the large deflecting straight beams, buckling beams...... and the buckling Elastica solution for an original compliant mechanism kinematic analysis. New compliant mechanism designs are presented to highlight where such combined kinematic analysis is required....

Teaching Theory X and Theory Y in Organizational Communication

Science.gov (United States)

Noland, Carey

2014-01-01

The purpose of the activity described here is to integrate McGregor's Theory X and Theory Y into a group application: design a syllabus that embodies either Theory X or Theory Y tenets. Students should be able to differentiate between Theory X and Theory Y, create a syllabus based on Theory X or Theory Y tenets, evaluate the different syllabi…

Electrode Cultivation and Interfacial Electron Transport in Subsurface Microorganisms

Science.gov (United States)

Karbelkar, A. A.; Jangir, Y.; Reese, B. K.; Wanger, G.; Anderson, C.; El-Naggar, M.; Amend, J.

2016-12-01

Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Microbes can use extracellular electron transfer (EET) as a metabolic strategy to interact with redox active surfaces. This process can be mimicked on electrode surfaces and hence can lead to enrichment and quantification of subsurface microorganisms A primary bioelectrochemical enrichment with different oxidizing and reducing potentials set up in a single bioreactor was applied in situ to subsurface microorganisms residing in iron oxide rich deposits in the Sanford Underground Research Facility. Secondary enrichment revealed a plethora of classified and unclassified subsurface microbiota on both oxidizing and reducing potentials. From this enrichment, we have isolated a Gram-positive Bacillus along with Gram-negative Cupriavidus and Anaerospora strains (as electrode reducers) and Comamonas (as an electrode oxidizer). The Bacillus and Comamonas isolates were subjected to a detailed electrochemical characterization in half-reactors at anodic and cathodic potentials, respectively. An increase in cathodic current upon inoculation and cyclic voltammetry measurements confirm the hypothesis that Comamonas is capable of electron uptake from electrodes. In addition, measurements of Bacillus on anodes hint towards novel mechanisms that allow EET from Gram-positive bacteria. This study suggests that electrochemical approaches are well positioned to dissect such extracellular interactions that may be prevalent in the subsurface, while using physical electrodes to emulate the microhabitats, redox and geochemical gradients, and the spatially dependent interspecies interactions encountered in the subsurface. Electrochemical

Applications of first order matricial theory to the calculation of storage ring designed for producing synchrotron radiation

International Nuclear Information System (INIS)

Machado, J.M.

1984-01-01

A review of first order matrix theory (linear approximation) used for calculating component elements of a particle accelerator employing the synchrotron principle of alternated gradient, is presented. Based on this theory, criteria for dimensioning synchrotron designed, exclusively for producing electromagnetic radiation, are established. The problem to find out optimum disposition of elements (straight line sections, quadrupolar magnetic lens, etc.) which take advantages of deflector magnets of the DCI synchrotron (Orsay Linear Accelerator Laboratory, French) aiming to construct a synchrotron designed to operate as electromagnetic radiation source, is solved. (M.C.K.) [pt

Classification of root canal microorganisms using electronic-nose and discriminant analysis

Directory of Open Access Journals (Sweden)

Özbilge Hatice

2010-11-01

Full Text Available Abstract Background Root canal treatment is a debridement process which disrupts and removes entire microorganisms from the root canal system. Identification of microorganisms may help clinicians decide on treatment alternatives such as using different irrigants, intracanal medicaments and antibiotics. However, the difficulty in cultivation and the complexity in isolation of predominant anaerobic microorganisms make clinicians resort to empirical medical treatments. For this reason, identification of microorganisms is not a routinely used procedure in root canal treatment. In this study, we aimed at classifying 7 different standard microorganism strains which are frequently seen in root canal infections, using odor data collected using an electronic nose instrument. Method Our microorganism odor data set consisted of 5 repeated samples from 7 different classes at 4 concentration levels. For each concentration, 35 samples were classified using 3 different discriminant analysis methods. In order to determine an optimal setting for using electronic-nose in such an application, we have tried 3 different approaches in evaluating sensor responses. Moreover, we have used 3 different sensor baseline values in normalizing sensor responses. Since the number of sensors is relatively large compared to sample size, we have also investigated the influence of two different dimension reduction methods on classification performance. Results We have found that quadratic type dicriminant analysis outperforms other varieties of this method. We have also observed that classification performance decreases as the concentration decreases. Among different baseline values used for pre-processing the sensor responses, the model where the minimum values of sensor readings in the sample were accepted as the baseline yields better classification performance. Corresponding to this optimal choice of baseline value, we have noted that among different sensor response model and

Microorganisms -indicators of the level of soil pollution with lead

OpenAIRE

Stavreva Veselinovska, Snezana

2011-01-01

Environmental pollution with heavy metals present a real threat to wildlife because the metals cannot be naturally decomposed as is the case with organic pollutants, and as such they can survive in the environment while accumulating the heavy metals in different parts. Pollution with metals can affect different organisms in the environment, such as microorganisms, plants and animals, but the degree of toxicity depends on the species. Microorganisms have different mechanisms of coping with...

Three-dimensional motion measurements of free-swimming microorganisms using digital holographic microscopy

International Nuclear Information System (INIS)

Lee, Sang Joon; Seo, Kyung Won; Choi, Yong Seok; Sohn, Myong Hwan

2011-01-01

A digital holographic microscope is employed to measure the 3D motion of free-swimming microorganisms. The focus function used to quantify image sharpness provides a better depth-directional accuracy with a smaller depth-of-focus compared with the intensity method in determining the depth-directional position of spherical particles of various diameters. The focus function is then applied to measure the 3D positions of free-swimming microorganisms, namely dinoflagellates C. polykrikoides and P. minimum. Both automatic segmentation and proper selection of a focus function for a selected segment are important processes in measuring the positional information of two free-swimming microorganisms of different shapes with various width-to-length ratios. The digital holographic microscopy technique improved in this work is useful for measuring 3D swimming trajectories, velocities and attitudes of hundreds of microorganisms simultaneously. It also exhibits exceptional depth-directional accuracy

Defensive properties of pyrrolizidine alkaloids against microorganisms

NARCIS (Netherlands)

Joosten, L.; Van Veen, J.A.

2011-01-01

The understanding of the selection factors that drive chemical diversification of secondary metabolites of constitutive defence systems in plants, such as pyrrolizidine alkaloids (PAs), is still incomplete. Historically, plants always have been confronted with microorganisms. Long before herbivores

A Malthusian curb on spatial structure in microorganism populations.

Science.gov (United States)

Martin, A P

2004-10-07

That all organisms are born in the company of a parent but die alone is a fundamental biological asymmetry. It has been suggested that this provides a deep-rooted source of spatial pattern formation for microorganisms even at the scale of the population. Such a theory, however, neglects the strong influence in nature of the limited and spatially variable availability of food. The tendency, first recognized by Thomas Malthus in the 18th century, of a population to out-strip its food resources will eventually lead, through local starvation, to the suppression of a heterogeneity growing within a population. Using a generic model it is demonstrated that including local food limitation of breeding strongly dampens spatial structure otherwise resulting from birth and death. The extent of this damping is shown to be a function of the strength of the coupling between organisms and their food and of the total abundance of organic material. Moreover, this work provides an example of a density-dependent process acting to diminish spatial structure rather than to create it and highlights the rich variety of behaviour that is missed by continuum models which fail to represent such local dynamics.

UV inactivation of pathogenic and indicator microorganisms

International Nuclear Information System (INIS)

Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

1985-01-01

Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts

UV inactivation of pathogenic and indicator microorganisms

Energy Technology Data Exchange (ETDEWEB)

Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

1985-06-01

Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts.

PROPOSAL FOR A MOOC INSTRUCTIONAL DESIGN BASED ON THE THEORY DEVELOPMENT AND MASTERY LEARNIG

Directory of Open Access Journals (Sweden)

José Emilio Sánchez-García

2016-07-01

Full Text Available The first massive open online courses cMOOC lacked an instructional design and have now shifted to models that have an instructional design called xMOOC. This document makes a proposal instructional design for MOOC using the simplified adaptive method SAM inspired by the theory development and strategy of Mastery Learning as part of the research method based on the design of the qualitative paradigm. The results explain and justify the procedure used for the preparation of instructional design. The conclusion that has been reached is that both SAM and strategy Mastery Learning has allowed the instructional design for MOOC easily with emphasis in practice but supported with theoretical, personalized basis by tracking post and considering the learning strategy for the domain.

Environment purification using microorganisms. Biseibutsu ni yoru kankyo joka

Energy Technology Data Exchange (ETDEWEB)

Tanaka, H [Asahi Glass Co. Ltd., Tokyo (Japan); Harada, S

1993-12-01

Technologies to purify polluted soils vary with kinds of pollutants, spread of pollution, and shapes of water veins. A method is used often that several wells are drilled in a polluted area, and water is circulated between upstream wells and downstream wells, where activities of microorganisms living in that particular environment are utilized to biodegrade the pollutants. This technology is called bioremediation. This paper deals with soil pollution by chemical substances, and describes development of a technology to remove pollution caused by PCB and petroleum which is thought difficult to apply the bioremediation technology among environment purifying technologies using microorganisms. The bioremediation of petroleum pollution assumes petroleum pollution on seashores. Discussions have been given on separation from sea water of petroleum decomposing microorganisms to be used in the bioremediation, and the number of petroleum decomposing bacteria in seas near Japan. As a result, it was made clear that a few kinds of bacteria will suffice for decomposition of main components in a mixture as complex as petroleum. 5 refs., 4 figs.

Investigations of subterranean microorganisms. Their importance for performance assessment of radioactive waste disposal

International Nuclear Information System (INIS)

Pedersen, K.

1995-06-01

This report presents a broad and thorough description of how microorganisms may influence safety of repositories for radioactive waste. First, an overview of the Swedish concepts for disposal is given, including a discussion of the geological, chemical and hydrological conditions in repositories. Then the limiting and stimulating factors for life of microorganisms are reviewed, such as relations to oxygen, temperature, pH, radiation, pressure, water and nutrients availability. Bacteria in the cycles of carbon, nitrogen, sulfur, iron, manganese and hydrogen are also discussed. A literature review of subterranean bacteria is given in chapter 4. Chapter 5 treats investigations of microorganisms in repository-like environments, and microbial corrosion and redox processes relevant for materials in the repository and for the mobility of radionuclides. Possibilities to predict the activity and presence of microorganisms through mathematical models are discussed in chapter 6. Chapter 7 summarizes the conclusion drawn in the report, how microorganisms may influence performance safety assessment of radioactive waste disposal, and also identifies research needs. 293 refs, 43 figs, 36 tabs

Investigations of subterranean microorganisms. Their importance for performance assessment of radioactive waste disposal

Energy Technology Data Exchange (ETDEWEB)

Pedersen, K [Goeteborg Univ. (Sweden). General and Marine Microbiology; Karlsson, Fred [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

1995-06-01

This report presents a broad and thorough description of how microorganisms may influence safety of repositories for radioactive waste. First, an overview of the Swedish concepts for disposal is given, including a discussion of the geological, chemical and hydrological conditions in repositories. Then the limiting and stimulating factors for life of microorganisms are reviewed, such as relations to oxygen, temperature, pH, radiation, pressure, water and nutrients availability. Bacteria in the cycles of carbon, nitrogen, sulfur, iron, manganese and hydrogen are also discussed. A literature review of subterranean bacteria is given in chapter 4. Chapter 5 treats investigations of microorganisms in repository-like environments, and microbial corrosion and redox processes relevant for materials in the repository and for the mobility of radionuclides. Possibilities to predict the activity and presence of microorganisms through mathematical models are discussed in chapter 6. Chapter 7 summarizes the conclusion drawn in the report, how microorganisms may influence performance safety assessment of radioactive waste disposal, and also identifies research needs. 293 refs, 43 figs, 36 tabs.

The use of the neutron radiography in the diagnosis of microorganisms contamination

International Nuclear Information System (INIS)

Wacha, Reinaldo; Crispim, Verginia R.; Lage, Claudia

2000-01-01

This work aims to present a new method of microorganism detection in several culture medium, such as potable water and corporal fluids. After the steps of processes of growth in culture medium, separation and resuspension in a boron based lid solution, the microorganisms are deposited in lines detectors and at last submitted to a thermal neutrons beam (≡ 2,2 x 10 5 n/cm 2 .s). The latent tracks registered by the alpha particles coming from the B(n,α)Li reaction are analyzed by an optical microscope, allowing the detection of microorganisms existence. (author)

The functional role of microorganisms in soil biocenoses in Ignalina NPP region

International Nuclear Information System (INIS)

Bagdanavichiene, Z.; Budavichiene, I.; Ramanauskiene, Z.

1995-01-01

Studies on group structure of soil microorganisms as well as regularities of changes in cellulotic activity in marsh biotopes of pine and birch forests in the littoral district of lake Drukshiai were carried out. The activity and directness of microorganisms, as well as dissociation rate of cellulose in soil depending on the changes of climatic conditions were evaluated. The effect of climate factors and thermal pollution on the activity of microorganisms and rate of cellulose degradation in soil was revealed in the standard area (Shashkai) near the disposal canal of Ignalina NPP. (author). 11 refs., 2 tabs., 3 figs

Designing technology for young children: what we can learn from theories of cognitive development

CSIR Research Space (South Africa)

Gelderblom, H

2008-10-01

Full Text Available on child development provides an ample starting point for setting up a useful framework of such guidelines. This paper demonstrates how the knowledge contained in psychological theories of child development can be translated into guidelines for the design...

Designing theoretically-informed implementation interventions: Fine in theory, but evidence of effectiveness in practice is needed

Directory of Open Access Journals (Sweden)

Reeves Scott

2006-02-01

Full Text Available Abstract The Improved Clinical Effectiveness through Behavioural Research Group (ICEBeRG authors assert that a key weakness in implementation research is the unknown applicability of a given intervention outside its original site and problem, and suggest that use of explicit theory offers an effective solution. This assertion is problematic for three primary reasons. First, the presence of an underlying theory does not necessarily ease the task of judging the applicability of a piece of empirical evidence. Second, it is not clear how to translate theory reliably into intervention design, which undoubtedly involves the diluting effect of "common sense." Thirdly, there are many theories, formal and informal, and it is not clear why any one should be given primacy. To determine whether explicitly theory-based interventions are, on average, more effective than those based on implicit theories, pragmatic trials are needed. Until empirical evidence is available showing the superiority of theory-based interventions, the use of theory should not be used as a basis for assessing the value of implementation studies by research funders, ethics committees, editors or policy decision makers.

Aerodynamic characteristics of wings designed with a combined-theory method to cruise at a Mach number of 4.5

Science.gov (United States)

Mack, Robert J.

1988-01-01

A wind-tunnel study was conducted to determine the capability of a method combining linear theory and shock-expansion theory to design optimum camber surfaces for wings that will fly at high-supersonic/low-hypersonic speeds. Three force models (a flat-plate reference wing and two cambered and twisted wings) were used to obtain aerodynamic lift, drag, and pitching-moment data. A fourth pressure-orifice model was used to obtain surface-pressure data. All four wing models had the same planform, airfoil section, and centerbody area distribution. The design Mach number was 4.5, but data were also obtained at Mach numbers of 3.5 and 4.0. Results of these tests indicated that the use of airfoil thickness as a theoretical optimum, camber-surface design constraint did not improve the aerodynamic efficiency or performance of a wing as compared with a wing that was designed with a zero-thickness airfoil (linear-theory) constraint.

Host Defense against Opportunist Microorganisms Following Trauma.

Science.gov (United States)

1979-06-01

Guide for Laboratory Animal, Resources, National Academy of Sciences - National Research Council. I ii t ___ ii A- KNOWLEDMENT The investigators express...and Candida albicans are the microorganisms which are most frequently associated with septic complica- tions in thermally injured patients. Management

How energetic and environmental constraints of microorganisms determine the carbon turnover in soils

Science.gov (United States)

Don, A.; Rödenbeck, C.; Gleixner, G.

2012-04-01

Microorganisms are the main catalysts driving carbon fluxes from soils. Traditional concepts of soil carbon stabilization failed to account for environmental and energy constraints of microorganisms. The distribution and density of organic carbon in the soil profile maybe a key factor determining the carbon stability and carbon flux. Decomposition is a two-step process following the Michaelis Menten kinetics: In a first step enzyme and substrate form a joint complex and then the decomposition reaction is catalyzed. Thus, biological decomposition relies on the encounter of substrate and the degradation catalyst, the microorganisms. Lower substrate concentration decreases the likelihood of an enzyme to hit a substrate molecule, to form an enzyme-substrate complex, and thus to catalyze the reaction. However, it was unproofen if this concept can be appliued to soils also. A long-term lab experiment revealed that the soil carbon turnover decreased with increasing carbon dilution due to mixture with soil minerals. The ability of microorganisms to move towards substrate in soils seems to be limited. To elucidate the effect of concentration-controlled carbon turnover, we devised the simple simulation model SCAMP based on the two-step kinetic with microorganism and carbon particles been simulated explicitly. The SCAMP model was able to simulate soil carbon profiles and age profiles in a realistic manner. The only carbon stabilization mechanism implemented in the model is the distribution of microorganisms and carbon particles in the soil and thus the availability of carbon for microorganism, which is especially important for subsoil carbon dynamics. The experiments and the model help to explain why large fractions of soil carbon have been stabilized for millennia and decoupled from the global carbon cycle.

The microorganisms as a renewable source of ecological clean fuel

International Nuclear Information System (INIS)

Shalygo, N.V.; Mel'nikov, S.S.; Manankina, E.E.; Budakova, E.A.; Kolyago, V.M.

2006-01-01

Five families of microorganisms (Bacillaceae, Rhodospirillaceae, Cyanophyceae, Chlorophyceae and Euglenophyceae) as hydrogen producers were tested and the conditions that are necessary for hydrogen photoproduction were investigated. It was shown, that the most effective producers of hydrogen were Rhodobacter spheroides, Clostridium sp.; Euglena gracilis var. bacillaris and Chlamydomonas reinhardtii. Addition of glucose, iron and vanadium salts resulted in the increase of hydrogen production. Polycultures consisted of two or three microorganisms were more effective hydrogen producers compared to separate monocultures. (authors)

Electrokinetic transport of aerobic microorganisms under low-strength electric fields.

Science.gov (United States)

Maillacheruvu, Krishnanand Y; Chinchoud, Preethi R

2011-01-01

To investigate the feasibility of utilizing low strength electric fields to transport commonly available mixed cultures such as those from an activated sludge process, bench scale batch reactor studies were conducted in sand and sandy loam soils. A readily biodegradable substrate, dextrose, was used to test the activity of the transported microorganisms. Electric field strengths of 7V, 10.5V, and 14V were used. Results from this investigation showed that an electric field strength of 0.46 Volts per cm was sufficient to transport activated sludge microorganisms across a sandy loam soil across a distance of about 8 cm in 72 h. More importantly, the electrokinetically transported microbial culture remained active and viable after the transport process and was biodegrade 44% of the dextrose in the soil medium. Electrokinetic treatment without microorganisms resulted in removal of 37% and the absence of any treatment yielded a removal of about 15%.

Potential applications of plant probiotic microorganisms in agriculture and forestry

Directory of Open Access Journals (Sweden)

Luciana Porto de Souza Vandenberghe

2017-07-01

Full Text Available Agriculture producers, pushed by the need for high productivity, have stimulated the intensive use of pesticides and fertilizers. Unfortunately, negative effects on water, soil, and human and animal health have appeared as a consequence of this indiscriminate practice. Plant probiotic microorganisms (PPM, also known as bioprotectants, biocontrollers, biofertilizers, or biostimulants, are beneficial microorganisms that offer a promising alternative and reduce health and environmental problems. These microorganisms are involved in either a symbiotic or free-living association with plants and act in different ways, sometimes with specific functions, to achieve satisfactory plant development. This review deals with PPM presentation and their description and function in different applications. PPM includes the plant growth promoters (PGP group, which contain bacteria and fungi that stimulate plant growth through different mechanisms. Soil microflora mediate many biogeochemical processes. The use of plant probiotics as an alternative soil fertilization source has been the focus of several studies; their use in agriculture improves nutrient supply and conserves field management and causes no adverse effects. The species related to organic matter and pollutant biodegradation in soil and abiotic stress tolerance are then presented. As an important way to understand not only the ecological role of PPM and their interaction with plants but also the biotechnological application of these cultures to crop management, two main approaches are elucidated: the culture-dependent approach where the microorganisms contained in the plant material are isolated by culturing and are identified by a combination of phenotypic and molecular methods; and the culture-independent approach where microorganisms are detected without cultivating them, based on extraction and analyses of DNA. These methods combine to give a thorough knowledge of the microbiology of the studied

What learning theories can teach us in designing neurofeedback treatments

Directory of Open Access Journals (Sweden)

Ute eStrehl

2014-11-01

Full Text Available Popular definitions of neurofeedback point out that neurofeedback is a process of operant conditioning which leads to self-regulation of brain activity. Self-regulation of brain activity is considered to be a skill. The aim of this paper is to clarify that not only operant conditioning plays a role in the acquisition of this skill. In order to design the learning process additional references have to be derived from classical conditioning, two-process-theory and in particular from skill learning and research into motivational aspects. The impact of learning by trial and error, cueing of behavior, feedback, reinforcement, and knowledge of results as well as transfer of self-regulation skills into everyday life will be analyzed in this paper. In addition to these learning theory basics this paper tries to summarize the knowledge about acquisition of self-regulation from neurofeedback studies with a main emphasis on clinical populations. As a conclusion it is hypothesized that learning to self-regulate has to be offered in a psychotherapeutic, i.e. behavior therapy framework.

What learning theories can teach us in designing neurofeedback treatments.

Science.gov (United States)

Strehl, Ute

2014-01-01

Popular definitions of neurofeedback point out that neurofeedback is a process of operant conditioning which leads to self-regulation of brain activity. Self-regulation of brain activity is considered to be a skill. The aim of this paper is to clarify that not only operant conditioning plays a role in the acquisition of this skill. In order to design the learning process additional references have to be derived from classical conditioning, two-process-theory and in particular from skill learning and research into motivational aspects. The impact of learning by trial and error, cueing of behavior, feedback, reinforcement, and knowledge of results as well as transfer of self-regulation skills into everyday life will be analyzed in this paper. In addition to these learning theory basics this paper tries to summarize the knowledge about acquisition of self-regulation from neurofeedback studies with a main emphasis on clinical populations. As a conclusion it is hypothesized that learning to self-regulate has to be offered in a psychotherapeutic, i.e., behavior therapy framework.

Periodontal Microorganisms and Cardiovascular Risk Markers in Youth With Type 1 Diabetes and Without Diabetes.

Science.gov (United States)

Merchant, Anwar T; Nahhas, Georges J; Wadwa, R Paul; Zhang, Jiajia; Tang, Yifan; Johnson, Lonnie R; Maahs, David M; Bishop, Franziska; Teles, Ricardo; Morrato, Elaine H

2016-04-01

A subset of periodontal microorganisms has been associated with cardiovascular disease (CVD), which is the leading complication of type 1 diabetes (t1DM). The authors therefore evaluated the association between periodontal microorganism groups and early markers of CVD in youth with t1DM. A cross-sectional analysis was conducted among youth aged 12 to 19 years at enrollment; 105 had t1DM for ≥5 years and were seeking care at the Barbara Davis Center, University of Colorado, from 2009 to 2011, and 71 did not have diabetes. Subgingival plaque samples were assessed for counts of 41 periodontal microorganisms using DNA-DNA hybridization. Microorganisms were classified using cluster analysis into four groups named red-orange, orange-green, blue/other, and yellow/other, modified from Socransky's color scheme for periodontal microorganisms. Subsamples (54 with t1DM and 48 without diabetes) also received a periodontal examination at the University of Colorado School of Dental Medicine. Participants were ≈15 years old on average, and 74% were white. Mean periodontal probing depth was 2 mm (SE 0.02), and 17% had bleeding on probing. In multivariable analyses, glycated hemoglobin (HbA1c) was inversely associated with the yellow/other cluster (microorganisms that are not associated with periodontal disease) among youth with t1DM. Blood pressure, triglycerides, low-density lipoprotein, high-density lipoprotein, and total cholesterol were not associated with microorganism clusters in this group. HbA1c was not associated with periodontal microorganism clusters among youth without diabetes. Among youth with t1DM who had good oral health, periodontal microorganisms were not associated with CVD risk factors.

Constructal Theory Of Design In Engineering And Nature

Directory of Open Access Journals (Sweden)

Adrian Bejan

2005-02-01

Full Text Available This is a brief introduction to an engineering theory on the origin and generation of geometric form in all flow systems: the animate, the inanimate and the engineered. The theory is named constructal, and is based on the thought that it is natural for currents to construct for themselves in time paths of greater flow access. It is shown that this process of flow path optimization can be reasoned on the basis of principle: the maximization of global performance subject to finite-size constraints. One example is the generation of tree-shaped flow patterns, as paths of least resistance between one point (source, sink and an infinity of points (area, volume, as in the circulatory, respiratory and nervous systems. An other is the generation of regular spacings in heat generating volumes, such as swarms of honeybees. The optimized tree-flow geometries account for allometric laws, e. g., the relationship between the total tube contact area and the body size, the proportionality between metabolic rate and body size raised to the power 3/4, the proportionality between breathing and heartbeating times and body size raised to the power 1/4, and the proportionality between the cruising speed of flying bodies (insects, birds, airplanes and body mass raised to the power 1/6. The optimized flow structures constitute robust designs, and robustness improves as the complexity of the system increases. Flow architectures that are more efficient look more natural.

Negotiating Tensions Between Theory and Design in the Development of Mailings for People Recovering From Acute Coronary Syndrome.

Science.gov (United States)

Witteman, Holly O; Presseau, Justin; Nicholas Angl, Emily; Jokhio, Iffat; Schwalm, J D; Grimshaw, Jeremy M; Bosiak, Beth; Natarajan, Madhu K; Ivers, Noah M

2017-03-01

Taking all recommended secondary prevention cardiac medications and fully participating in a formal cardiac rehabilitation program significantly reduces mortality and morbidity in the year following a heart attack. However, many people who have had a heart attack stop taking some or all of their recommended medications prematurely and many do not complete a formal cardiac rehabilitation program. The objective of our study was to develop a user-centered, theory-based, scalable intervention of printed educational materials to encourage and support people who have had a heart attack to use recommended secondary prevention cardiac treatments. Prior to the design process, we conducted theory-based interviews and surveys with patients who had had a heart attack to identify key determinants of secondary prevention behaviors. Our interdisciplinary research team then partnered with a patient advisor and design firm to undertake an iterative, theory-informed, user-centered design process to operationalize techniques to address these determinants. User-centered design requires considering users' needs, goals, strengths, limitations, context, and intuitive processes; designing prototypes adapted to users accordingly; observing how potential users respond to the prototype; and using those data to refine the design. To accomplish these tasks, we conducted user research to develop personas (archetypes of potential users), developed a preliminary prototype using behavior change theory to map behavior change techniques to identified determinants of medication adherence, and conducted 2 design cycles, testing materials via think-aloud and semistructured interviews with a total of 11 users (10 patients who had experienced a heart attack and 1 caregiver). We recruited participants at a single cardiac clinic using purposive sampling informed by our personas. We recorded sessions with users and extracted key themes from transcripts. We held interdisciplinary team discussions to

New micro-organism

Energy Technology Data Exchange (ETDEWEB)

Takakuwa, Masayoshi; Hashimoto, Gotaro

1987-09-12

Invention relates with a new organism for the coal liquefying desulfurization. This micro-organism conducts a good sporulation on a culture medium which contains a coal as an only carbon source. It belongs to Penicillium and named Penicillium MT-6001 registered at Fermentation Research Institute No. 8463. Coal powder is thrown into a reaction vessel which accommodated a culture solution of this bacteria, and the surface of the solution is covered with liquid paraffin; coal powder is treated of liquefaction for about 5 hours while maintaining the anaerobic condition and slowly agitating to form a transparent solution layer on the surface of the reactor together with liquid paraffin. Liquefied product shows an analysis pattern similar to naphthenic petroleum containing a lipid with polar radical. (2 figs)

[Sorption of microorganisms by fiber materials].

Science.gov (United States)

Nikovskaia, G N; Gordienko, A S; Globa, L I

1986-01-01

Candida guilliermondii and Escherichia coli cells were adsorbed on glass and basalt fibres with a similar specific surface, but with a different charge. The quantity of adsorbed microorganisms did not depend on the type and charge of a fibre surface. However, cells were adsorbed faster and more firmly on positively charged and uncharged fibres than on negatively charged fibres.

Thermophilic microorganisms in biomining.

Science.gov (United States)

Donati, Edgardo Rubén; Castro, Camila; Urbieta, María Sofía

2016-11-01

Biomining is an applied biotechnology for mineral processing and metal extraction from ores and concentrates. This alternative technology for recovering metals involves the hydrometallurgical processes known as bioleaching and biooxidation where the metal is directly solubilized or released from the matrix for further solubilization, respectively. Several commercial applications of biomining can be found around the world to recover mainly copper and gold but also other metals; most of them are operating at temperatures below 40-50 °C using mesophilic and moderate thermophilic microorganisms. Although biomining offers an economically viable and cleaner option, its share of the world´s production of metals has not grown as much as it was expected, mainly considering that due to environmental restrictions in many countries smelting and roasting technologies are being eliminated. The slow rate of biomining processes is for sure the main reason of their poor implementation. In this scenario the use of thermophiles could be advantageous because higher operational temperature would increase the rate of the process and in addition it would eliminate the energy input for cooling the system (bioleaching reactions are exothermic causing a serious temperature increase in bioreactors and inside heaps that adversely affects most of the mesophilic microorganisms) and it would decrease the passivation of mineral surfaces. In the last few years many thermophilic bacteria and archaea have been isolated, characterized, and even used for extracting metals. This paper reviews the current status of biomining using thermophiles, describes the main characteristics of thermophilic biominers and discusses the future for this biotechnology.

Turbulence from a microorganism's perspective: Does the open ocean feel different than a coral reef?

Science.gov (United States)

Pepper, Rachel; Variano, Evan; Koehl, M. A. R.

2012-11-01

Microorganisms in the ocean live in turbulent flows. Swimming microorganisms navigate through the water (e.g. larvae land on suitable substrata, predators find patches of prey), but the mechanisms by which they do so in turbulent flow are poorly understood as are the roles of passive transport versus active behaviors. Because microorganisms are smaller than the Kolmagorov length (the smallest scale of eddies in turbulent flow), they experience turbulence as a series of linear gradients in the velocity that vary in time. While the average strength of these gradients and a timescale can be computed from some typical characteristics of the flow, such as the turbulent kinetic energy or the dissipation rate, there are indications that organisms are disproportionally affected by rare, extreme events. Understanding the frequency of such events in different environments will be critical to understanding how microorganisms respond to and navigate in turbulence. To understand the hydrodynamic cues that microorganisms experience in the ocean we must measure velocity gradients in realistic turbulent flow on the spatial and temporal scales encountered by microorganisms. We have been exploring the effect of the spatial resolution of PIV and DNS of turbulent flow on the presence of velocity gradients of different magnitudes at the scale of microorganisms. Here we present some results of PIV taken at different resolutions in turbulent flow over rough biological substrata to illustrate the challenges of quantifying the fluctuations in velocity gradients encountered by aquatic microorganisms.

The effect of implementing cognitive load theory-based design principles in virtual reality simulation training of surgical skills: a randomized controlled trial

DEFF Research Database (Denmark)

Andersen, Steven Arild Wuyts; Mikkelsen, Peter Trier; Konge, Lars

2016-01-01

Cognitive overload can inhibit learning, and cognitive load theory-based instructional design principles can be used to optimize learning situations. This study aims to investigate the effect of implementing cognitive load theory-based design principles in virtual reality simulation training...

Building bridges between theory and practice in medical education using a design-based research approach: AMEE Guide No. 60.

Science.gov (United States)

Dolmans, Diana H J M; Tigelaar, D

2012-01-01

Medical education research has grown enormously over the past 20 years, but it does not sufficiently make use of theories, according to influential leaders and researchers in this field. In this AMEE Guide, it is argued that design-based research (DBR) studies should be conducted much more in medical education design research because these studies both advance the testing and refinement of theories and advance educational practice. In this Guide, the essential characteristics of DBR as well as how DBR differs from other approach such as formative evaluation are explained. It is also explained what the pitfalls and challenges of DBR are. The main challenges deal with how to insure that DBR studies reveal findings that are of a broader relevance than the local situation and how to insure that DBR contributes toward theory testing and refinement. An example of a series of DBR studies on the design of a teaching portfolio in higher education that is aimed at stimulating a teacher's professional development is described, to illustrate how DBR studies actually work in practice. Finally, it is argued that DBR-studies could play an important role in the advancement of theory and practice in the two broad domains of designing or redesigning work-based learning environments and assessment programs.

Identification of Microorganisms by Modern Analytical Techniques.

Science.gov (United States)

Buszewski, Bogusław; Rogowska, Agnieszka; Pomastowski, Paweł; Złoch, Michał; Railean-Plugaru, Viorica

2017-11-01

Rapid detection and identification of microorganisms is a challenging and important aspect in a wide range of fields, from medical to industrial, affecting human lives. Unfortunately, classical methods of microorganism identification are based on time-consuming and labor-intensive approaches. Screening techniques require the rapid and cheap grouping of bacterial isolates; however, modern bioanalytics demand comprehensive bacterial studies at a molecular level. Modern approaches for the rapid identification of bacteria use molecular techniques, such as 16S ribosomal RNA gene sequencing based on polymerase chain reaction or electromigration, especially capillary zone electrophoresis and capillary isoelectric focusing. However, there are still several challenges with the analysis of microbial complexes using electromigration technology, such as uncontrolled aggregation and/or adhesion to the capillary surface. Thus, an approach using capillary electrophoresis of microbial aggregates with UV and matrix-assisted laser desorption ionization time-of-flight MS detection is presented.

Optimal design of a beam-based dynamic vibration absorber using fixed-points theory

Science.gov (United States)

Hua, Yingyu; Wong, Waion; Cheng, Li

2018-05-01

The addition of a dynamic vibration absorber (DVA) to a vibrating structure could provide an economic solution for vibration suppressions if the absorber is properly designed and located onto the structure. A common design of the DVA is a sprung mass because of its simple structure and low cost. However, the vibration suppression performance of this kind of DVA is limited by the ratio between the absorber mass and the mass of the primary structure. In this paper, a beam-based DVA (beam DVA) is proposed and optimized for minimizing the resonant vibration of a general structure. The vibration suppression performance of the proposed beam DVA depends on the mass ratio, the flexural rigidity and length of the beam. In comparison with the traditional sprung mass DVA, the proposed beam DVA shows more flexibility in vibration control design because it has more design parameters. With proper design, the beam DVA's vibration suppression capability can outperform that of the traditional DVA under the same mass constraint. The general approach is illustrated using a benchmark cantilever beam as an example. The receptance theory is introduced to model the compound system consisting of the host beam and the attached beam-based DVA. The model is validated through comparisons with the results from Abaqus as well as the Transfer Matrix method (TMM) method. Fixed-points theory is then employed to derive the analytical expressions for the optimum tuning ratio and damping ratio of the proposed beam absorber. A design guideline is then presented to choose the parameters of the beam absorber. Comparisons are finally presented between the beam absorber and the traditional DVA in terms of the vibration suppression effect. It is shown that the proposed beam absorber can outperform the traditional DVA by following this proposed guideline.

Robert M. Gagne and M. David Merrill: In Conversation. No. 3: An Overview of M. David Merrill's New Component Design Theory.

Science.gov (United States)

Twitchell, David, Ed.

1990-01-01

This third in a series of edited transcripts based on a conference at Utah State University describes Merrill's Component Design Theory (CDT) and compares it to his earlier Component Display Theory. Topics discussed include concept structures, knowledge acquisition, components of an instructional design system, and a new CDT matrix. (10…

Ecological aspects of microorganisms inhabiting uranium mill tailings

Science.gov (United States)

Miller, C.L.; Landa, E.R.; Updegraff, D.M.

1987-01-01

Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

Changes in Gram Negative Microorganisms' Resistance Pattern During 4 Years Period in a Referral Teaching Hospital; a Surveillance Study

Directory of Open Access Journals (Sweden)

Hossein Khalili

2012-09-01

Full Text Available Background and purpose Surveillance studies evaluating antimicrobial susceptibilities are of great value in preventing the spread of resistant pathogens by elucidating the trend of resistance in commonly used antibiotics and as a consequence providing information for prescribing the most appropriate agent. This study is a longitudinal antimicrobial resistance surveillance study designed to evaluate the trend in antimicrobial resistance to gram negative microorganisms from 2007 to 2010. Method:During a four-year period (2007-2010 isolates derived from all patients admitted to infectious diseases ward of Imam Khomeini Hospital, the major referral center for infectious disease in Iran with the highest admission rates, were evaluated. Based on disk diffusion method and zone of inhibition size, the microorganism was regarded as to be sensitive, resistant or has intermediate susceptibility to the antimicrobial agents. Results:The widest spread Gram-negative microorganism in all of isolates taken together in our study was E.coli (30% followed by Stenotrophomonas maltophilia in 28.6% and Enterobacter spp. in 11.9%, respectively. The susceptibility to amikacin, imipenem, piperacillin/tazobactam, and nitrofurantoin was equal or above 50% for all microorganisms over four years. However, the susceptibility to ampicillin, ampicillin/sulbactam, cefotaxim, and ceftriaxone was less than 50% in derived isolates during the study period.Conclusion:In conclusion, the finding of the present study revealed that resistance rate to common antimicrobial agents in Iran is growing and isolates were susceptible mostly to broadspectrum antibiotics including imipenem and piperacillin/tazobactam

Generalized perturbation theory for LWR depletion analysis and core design applications

International Nuclear Information System (INIS)

White, J.R.; Frank, B.R.

1986-01-01

A comprehensive time-dependent perturbation theory formulation that includes macroscopic depletion, thermal-hydraulic and poison feedback effects, and a criticality reset mechanism is developed. The methodology is compatible with most current LWR design codes. This new development allows GTP/DTP methods to be used quantitatively in a variety of realistic LWR physics applications that were not possible prior to this work. A GTP-based optimization technique for incore fuel management analyses is addressed as a promising application of the new formulation

Learning Theory Expertise in the Design of Learning Spaces: Who Needs a Seat at the Table?

Science.gov (United States)

Rook, Michael M.; Choi, Koun; McDonald, Scott P.

2015-01-01

This study highlights the impact of including stakeholders with expertise in learning theory in a learning space design process. We present the decision-making process during the design of the Krause Innovation Studio on the campus of the Pennsylvania State University to draw a distinction between the architect and faculty member's decision-making…

Growth response of microorganisms to different molecular fractions of lignite

Energy Technology Data Exchange (ETDEWEB)

Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

1990-01-01

Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

Design methods and design theory for architectural design management

NARCIS (Netherlands)

Achten, H.H.; Otter, den A.F.H.J.; Achten, H.H.; Pels, H.J.

2008-01-01

Most parties that an architectural design manager meets in daily practice are engaged to some degree with design. What these parties are actually doing in a project is contingent with the concrete design project. Additionally, each party has some stake, and may employ different strategies to solve

Determining the relationship between atherosclerosis and periodontopathogenic microorganisms in chronic periodontitis patients.

Science.gov (United States)

Bozoglan, Alihan; Ertugrul, Abdullah Seckin; Taspınar, Mehmet; Yuzbasioglu, Betul

2017-05-01

The aim of this study is to determine the relationship between atherosclerosis and periodontopathogenic microorganisms in chronic periodontitis patients following periodontal treatment. A total of 40 patients were included in the study. 20 of these patients diagnosed with atherosclerosis and chronic periodontitis formed the test group. The remaining 20 patients were systemically healthy patients diagnosed with chronic periodontitis and formed the control group. All patients had nonsurgical periodontal treatment. The periodontopathogenic microorganism levels were determined at baseline and at 6 months in microbial dental plaque samples and WBC, LDL, HDL, PLT, fibrinogen, creatinine and hs-CRP levels were determined by blood samples. Statistically significant reduction has been achieved in clinical periodontal parameters following non-surgical periodontal treatment in test and control groups. Following periodontal treatment, WBC, LDL, PLT, fibrinogen, creatinine and hs-CRP levels significantly decreased and HDL levels significantly increased in both test and control groups. Similarly, the periodontopathogenic microorganism levels significantly decreased following periodontal treatment in the test and control groups. A statistically significant positive correlation has been determined between the periodontopathogenic microorganism levels and WBC, LDL, PLT, fibrinogen, creatinine, and hs-CRP levels in the test group. The association between hs-CRP, WBC, LDL, PLT, fibrinogen, creatinine, and the amount of periodontopathogenic microorganisms indicates the possibility that periodontal treatment could decrease the risk atherosclerosis. More studies must be conducted in order for these results to be supported.

THE EXTREMELY HALOPHILIC MICROORGANISMS, A POSSIBLE MODEL FOR LIFE ON OTHER PLANETS

Directory of Open Access Journals (Sweden)

Sergiu Fendrihan

2017-12-01

Full Text Available Abstract The group of halophilic Archaea was discovered in the beginning of XX th century. They are able to live in more than 2-3 M of sodium chloride concentration that can be found in hypersaline natural lakes, in alkaline saline lakes, in man-made hypersaline mats, in rock salt, in very salted foods, on salted fish, on salted hides, in stromatolites, in saline soils. Their adaptations consist in resistance to high ionic contents with internal accumulation of K ions in order to face high Na ion content from the near environment. They belong to the Halobacteriaceae family. Their adaptation and their resistance to UV radiation and their resistance in oligotrophic conditions in rock salt, apparently over geological times, increase the possibility to find similar microorganisms in the Martian subsurface and in meteorites, and to support the panspermia theory. Some of the research of a working group in this field of activity and their possible uses are shortly reviewed here.

Biobased production of alkanes and alkenes through metabolic engineering of microorganisms

DEFF Research Database (Denmark)

Kang, Min Kyoung; Nielsen, Jens

2017-01-01

Advancement in metabolic engineering of microorganisms has enabled bio-based production of a range of chemicals, and such engineered microorganism can be used for sustainable production leading to reduced carbon dioxide emission there. One area that has attained much interest is microbial...... hydrocarbon biosynthesis, and in particular, alkanes and alkenes are important high-value chemicals as they can be utilized for a broad range of industrial purposes as well as ‘drop-in’ biofuels. Some microorganisms have the ability to biosynthesize alkanes and alkenes naturally, but their production level...... is extremely low. Therefore, there have been various attempts to recruit other microbial cell factories for production of alkanes and alkenes by applying metabolic engineering strategies. Here we review different pathways and involved enzymes for alkane and alkene production and discuss bottlenecks...

The influence of selected nanomaterials on microorganisms

Czech Academy of Sciences Publication Activity Database

Brandeburová, P.; Birošová, L.; Vojs, M.; Kromka, Alexander; Gál, M.; Tichý, J.; Híveš, J.; Mackul´ak, T.

2017-01-01

Roč. 148, č. 3 (2017), s. 525-530 ISSN 0026-9247 R&D Projects: GA ČR GA15-01687S Institutional support: RVO:68378271 Keywords : nanomaterials * nanotechnologies * microorganisms * toxicity Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.282, year: 2016

An experiment designed to verify the general theory of relativity; Une experience destinee a verifier la theorie de la relativite generalisee

Energy Technology Data Exchange (ETDEWEB)

Surdin, Maurice [Commissariat a l' energie atomique et aux energies alternatives - CEA (France)

1960-07-01

The project for an experiment which uses the effect of gravitation on Maser-type clocks placed on the ground at two different heights and which is designed to verify the general theory of relativity. Reprint of a paper published in Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 299-301, sitting of 11 January 1960 [French] Projet d'une experience, utilisant l'effet de gravitation sur des horloges du type Maser placees sur la terre a deux altitudes differentes, et destinee a verifier la theorie de la relativite generalisee. Reproduction d'un article publie dans les Comptes rendus des seances de l'Academie des Sciences, t. 250, p. 299-301, seance du 11 janvier 1960.

Games and Diabetes: A Review Investigating Theoretical Frameworks, Evaluation Methodologies, and Opportunities for Design Grounded in Learning Theories.

Science.gov (United States)

Lazem, Shaimaa; Webster, Mary; Holmes, Wayne; Wolf, Motje

2015-09-02

Here we review 18 articles that describe the design and evaluation of 1 or more games for diabetes from technical, methodological, and theoretical perspectives. We undertook searches covering the period 2010 to May 2015 in the ACM, IEEE, Journal of Medical Internet Research, Studies in Health Technology and Informatics, and Google Scholar online databases using the keywords "children," "computer games," "diabetes," "games," "type 1," and "type 2" in various Boolean combinations. The review sets out to establish, for future research, an understanding of the current landscape of digital games designed for children with diabetes. We briefly explored the use and impact of well-established learning theories in such games. The most frequently mentioned theoretical frameworks were social cognitive theory and social constructivism. Due to the limitations of the reported evaluation methodologies, little evidence was found to support the strong promise of games for diabetes. Furthermore, we could not establish a relation between design features and the game outcomes. We argue that an in-depth discussion about the extent to which learning theories could and should be manifested in the design decisions is required. © 2015 Diabetes Technology Society.

Characteristics of airborne micro-organisms in a neurological intensive care unit: Results from China.

Science.gov (United States)

Yu, Yao; Yin, Sufeng; Kuan, Yi; Xu, Yingjun; Gao, Xuguang

2015-06-01

To describe the characteristics of airborne micro-organisms in the environment in a Chinese neurological intensive care unit (NICU). This prospective study monitored the air environment in two wards (large and small) of an NICU in a tertiary hospital in China for 12 months, using an LWC-1 centrifugal air sampler. Airborne micro-organisms were identified using standard microbiology techniques. The mean ± SD number of airborne bacteria was significantly higher in the large ward than in the small ward (200 ± 51 colony-forming units [CFU]/m(3) versus 110 ± 40 CFU/m(3), respectively). In the large ward only, the mean number of airborne bacteria in the autumn was significantly higher than in any of the other three seasons. A total of 279 airborne micro-organisms were identified (large ward: 195; small ward: 84). There was no significant difference in the type and distribution of airborne micro-organisms between the large and small wards. The majority of airborne micro-organisms were Gram-positive cocci in both wards. These findings suggest that the number of airborne micro-organisms was related to the number of patients on the NICU ward. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Antimicrobial activity of jasmine oil against oral microorganisms

Science.gov (United States)

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.

Detection of extracellular proteases from microorganisms on agar plates

Directory of Open Access Journals (Sweden)

Alane Beatriz Vermelho

1996-12-01

Full Text Available We present herein an improved assay for detecting the presence of extracellular proteases from microorganisms on agar plates. Using different substrates (gelatin, BSA, hemoglobin incorporated into the agar and varying the culture medium composition, we were able to detect proteolytic activities from Pseudomonas aeruginosa, Micrococcus luteus and Serratia marcescens as well as the influence that these components displayed in the expression of these enzymes. For all microorganisms tested we found that in agar-BHI or yeast extract medium containing gelatin the sensitivity of proteinase detection was considerably greater than in BSA-agar or hemoglobin-agar. However, when BSA or hemoglobin were added to the culture medium, there was an increase in growth along with a marked reduction in the amount of proteinase production. In the case of M. luteus the incorporation of glycerol in BHI or yeast extract gelatin-agar induced protease liberation. Our results indicate that the technique described here is of value for detecting extracellular proteases directly in the culture medium, by means of a qualitative assay, simple, inexpensive, straight forward method to assess the presence of the proteolytic activity of a given microorganism colony with great freedom in substrate selection.

An overview of means-end theory: potential application in consumer-oriented food product design

NARCIS (Netherlands)

Costa, A.I.A.; Dekker, M.; Jongen, W.M.F.

2004-01-01

This paper presents an overview of the means-end chain theory and associated techniques, and discusses the virtues and shortcomings of its potential application in consumer-oriented food product design. This overview, based on literature in the food area, presents also the process of conducting a

Applying Theory of Mind Concepts When Designing Interventions Targeting Social Cognition among Youth Offenders

Science.gov (United States)

Noel, Kristine K.; Westby, Carol

2014-01-01

This study employed a multiple baseline, across-participants, single-subject design to investigate the feasibility of an individual, narrative-based, social problem-solving intervention on the social problem-solving, narrative, and theory of mind (ToM) abilities of 3 incarcerated adolescent youth offenders identified as having emotional…

Stimulation of soil microorganisms in pesticide-contaminated soil using organic materials

OpenAIRE

Ima Yudha Perwira; Kiwako S. Araki; Motoki Kubo; Dinesh Adhikari

2016-01-01

Agrochemicals such as pesticides have contributed to significant increases in crop yields; however, they can also be linked to adverse effects on human health and soil microorganisms. For efficient bioremediation of pesticides accumulated in agricultural fields, stimulation of microorganisms is necessary. In this study, we investigated the relationships between bacterial biomass and total carbon (TC) and total nitrogen (TN) in 427 agricultural soils. The soil bacterial biomass was generally p...

Undersized description on motile gyrotactic micro-organisms individualities in MHD stratified water-based Newtonian nanofluid

Science.gov (United States)

Rehman, Khalil Ur; Malik, Aneeqa Ashfaq; Tahir, M.; Malik, M. Y.

2018-03-01

The current pagination summarized the influence of bio-convection Schmidt number, bio-convection Peclet number and micro-organisms concentration difference parameter on the density of motile gyrotactic micro-organisms when they have interaction with the thermally stratified magneto-nanofluid flow past a vertical stretching surface. It is observed that the density of motile microorganisms is the decreasing function of the bio-convection Schmidt and Peclet numbers. It is trusted that the outcomes of present analysis will serve as a helping source for the upcoming developments regarding individualities of motile gyrotactic micro-organisms subject to boundary layer flows induced by stretching surfaces.

Biotransformation of Spanish coals by microorganisms; Biotransformacion de Carbones Espanoles por Microorganismos

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

some newly isolated microorganisms could solubilized different kinds of Spanish coals (hard coal, subbituminous coal and lignite). Certain fungi and bacteria could solubilized lignite when growing in a mineral medium. However, to solubilized higher rank coals (hard coal and subbituminous coal) microorganisms require a complete medium. Microorganisms, which showed higher capacity to solubilized coal, were incubated in the presence of coal (hard coal, subbituminous coal and lignite) at the optimal conditions to get coal liquefaction/solubilization. The resultant products were analysed by IR and UV/visible spectrometry. No major differences among the original coal, solubilized/liquefied coal and residual coal were detected. However, an increase in metallic carboxylate and a decrease in OH'- carboxylic groups were observed in the liquefied lignite. Humic acids derived from original lignite residual lignite and liquefied/solubilized lignite by microorganisms were analysed. Several differences were observed in the humic acids extracted from the liquefied lignite, such as an increase in the total acidity and in the proportion of the phenolic groups. Differences on the humic acid molecular weight were observed too. Several fungal and bacterial strains were able to grow using humic acids as sole carbon source. Microorganisms growing in humic acid were observed by Scanning Electron Microscopy. Besides, the coal solubilization capacity of several fungal strains (M2, m$ and AGI) growing in different culture media was assayed. In order to get some insight into the mechanisms of the liquefaction/solubilization of Spanish coals (hard coal, subbituminous coal and lignite) by these microorganisms, some features in the culture supernatants were studied: pH values; extracellular specific proteins; enzyme activities possibly related with coal solubilization and the presence of oxalate. M2 and M4 fungal strains grown in the presence of coal produced some specific extracellular proteins

Biotransformation of Spanish coals by microorganisms; Biotransformacion de Carbones Espanoles por Microorganismos

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

some newly isolated microorganisms could solubilized different kinds of Spanish coals (hard coal, subbituminous coal and lignite). Certain fungi and bacteria could solubilized lignite when growing in a mineral medium. However, to solubilized higher rank coals (hard coal and subbituminous coal) microorganisms require a complete medium. Microorganisms, which showed higher capacity to solubilized coal, were incubated in the presence of coal (hard coal, subbituminous coal and lignite) at the optimal conditions to get coal liquefaction/solubilization. The resultant products were analysed by IR and UV/visible spectrometry. No major differences among the original coal, solubilized/liquefied coal and residual coal were detected. However, an increase in metallic carboxylate and a decrease in OH'- carboxylic groups were observed in the liquefied lignite. Humic acids derived from original lignite residual lignite and liquefied/solubilized lignite by microorganisms were analysed. Several differences were observed in the humic acids extracted from the liquefied lignite, such as an increase in the total acidity and in the proportion of the phenolic groups. Differences on the humic acid molecular weight were observed too. Several fungal and bacterial strains were able to grow using humic acids as sole carbon source. Microorganisms growing in humic acid were observed by Scanning Electron Microscopy. Besides, the coal solubilization capacity of several fungal strains (M2, m$ and AGI) growing in different culture media was assayed. In order to get some insight into the mechanisms of the liquefaction/solubilization of Spanish coals (hard coal, subbituminous coal and lignite) by these microorganisms, some features in the culture supernatants were studied: pH values; extracellular specific proteins; enzyme activities possibly related with coal solubilization and the presence of oxalate. M2 and M4 fungal strains grown in the presence of coal produced some specific extracellular

Effect of enhanced UV-B radiation on motile microorganisms

International Nuclear Information System (INIS)

Haeder, D.P.

1985-02-01

The effect of slightly increased UV-B radiation was studied in four taxonomically very different microorganisms: the gliding prokaryotic cyanobacterium, Phormidium, the unicellular green alga Cosmarium, the flagellate Euglena and the cellular slime mold Dictyostelium. UV-B doses which can be expected as a result of a slight decrease of the protective ozone layer in the stratosphere, do not kill or damage the microorganisms visibly. However, such UV-B doses impair the development, motility and photoorientation of these organisms. Due to the inhibition of these physiological important parameters the organisms cannot respond adequately to the changing factors in their environment, which prevents the survival of the populations. (orig.) [de

False identification of other microorganisms as Staphylococcus ...

African Journals Online (AJOL)

Methods: 507 microorganisms which have been previously identified as S. aureus in 8 States in Southern Nigeria through characteristic morphology on blood agar, Gram staining, growth and fermentation on Mannitol Salt Agar and coagulase formation were collected. All the isolates were identified in this study through ...

Ecophysiology of microorganisms in microbial elctrolysis cells

NARCIS (Netherlands)

Croese, E.

2012-01-01

One of the main challenges for improvement of the microbial electrolysis cell (MEC) has been the reduction of the cost of the cathode catalyst. As catalyst at the cathode, microorganisms offer great possibilities. Previous research has shown the principle possibilities for the biocathode for H2

Microorganisms as bioindicators of pollutants in soil

Directory of Open Access Journals (Sweden)

Milošević Nada

2010-01-01

Full Text Available Microorganisms are the predominant portion of the soil's biological phase and they are indicators of soil health and quality. Soil microorganisms a take part in degradation of organic and inorganic compounds, b their activity, number and diversity may serve as bioindicators of toxic effects on soil biological activity, c some microbial species may be used for soil bioremediation and d some sensitive microbes are used in eco-toxicity tests. The primary microbial population starts to decompose herbicides several days after their arrival into the soil. The secondary population produces induced enzymes and decomposes herbicides after a period of adaptation. Certain microbial groups are indifferent to the applied herbicides. Effect of heavy metals on soil microbial activity depends on the element, their concentration, microbial species, as well as physical and chemical soil properties. Toxic level of individual pollutants depends on their origin and composition. However, combined application of chemicals makes room for the occurrence of synergistic toxic effects detrimental for the ecosystem and human health. .

Raft-like membrane domains in pathogenic microorganisms.

Science.gov (United States)

Farnoud, Amir M; Toledo, Alvaro M; Konopka, James B; Del Poeta, Maurizio; London, Erwin

2015-01-01

The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Assessment of microorganisms from Indonesian Oil Fields

Energy Technology Data Exchange (ETDEWEB)

Kadarwati, S.; Udiharto, M.; Rahman, M.; Jasjfi, E.; Legowo, E.H. [Research and Development Centre for Oil and Gas Technology LEMIGAS, Jakarta Selatan (Indonesia)

1995-12-31

Petroleum resources have been the mainstay of the national development in Indonesia. However, resources are being depleted after over a century of exploitation, while the demand continues to grow with the rapid economic development of the country. In facing the problem, EOR has been applied in Indonesia, such as the steamflooding project in Duri field, but a more energy efficient technology would be preferable. Therefore, MEOR has been recommended as a promising solution. Our study, aimed at finding indigenous microorganisms which can be developed for application in MEOR, has isolated microbes from some oil fields of Indonesia. These microorganisms have been identified, their activities studied, and the effects of their metabolisms examined. This paper describes the research carried out by LEMIGAS in this respect, giving details on the methods of sampling, incubation, identification, and activation of the microbes as well as tests on the effects of their metabolites, with particular attention to those with potential for application in MEOR.

Genome-Based Studies of Marine Microorganisms to Maximize the Diversity of Natural Products Discovery for Medical Treatments

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Xin-Qing Zhao

2011-01-01

Full Text Available Marine microorganisms are rich source for natural products which play important roles in pharmaceutical industry. Over the past decade, genome-based studies of marine microorganisms have unveiled the tremendous diversity of the producers of natural products and also contributed to the efficiency of harness the strain diversity and chemical diversity, as well as the genetic diversity of marine microorganisms for the rapid discovery and generation of new natural products. In the meantime, genomic information retrieved from marine symbiotic microorganisms can also be employed for the discovery of new medical molecules from yet-unculturable microorganisms. In this paper, the recent progress in the genomic research of marine microorganisms is reviewed; new tools of genome mining as well as the advance in the activation of orphan pathways and metagenomic studies are summarized. Genome-based research of marine microorganisms will maximize the biodiscovery process and solve the problems of supply and sustainability of drug molecules for medical treatments.

Development of genetic methods for detection of pathogenic microorganisms in irradiated food

International Nuclear Information System (INIS)

2010-01-01

The existence of injured microorganisms in food and their recovery during culturing procedures is critical. Injured microorganisms present a potential threat in food safety since they may repair themselves under suitable conditions. This study provides development of recovery methods for detection of injured foodborne microorganisms, after irradiation treatment at different doses. For this purpose, iniatially the methods of recovery were compared at different irradiation doses. At the second step, antibiotic resistance of foodborne pathogens was determined. After determination of antibiotic resistance, recovery methods were modified for reversibly injured foodborne pathogens at different doses after irradiation treatment . Finally, damages of DNA were detected by a spectrophotometric method after 1.0 kGy irradiation treatment

Isolation of Electrogenic Microorganisms with Potential to Reduce Hexavalent Chromium

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Alexander Mora Collazos

2017-01-01

Full Text Available Isolation of cultivable microorganisms was made from the biofilm formed on the anode of a microbial fuel cell put into operation for 30 days; isolated microorganisms were evaluated for their ability to produce energy and reduce the hexavalent chromium Cr (VI. Five microorganisms were isolated, which were characterized by analysis of 16S rRNA gene, placing them in four bacterial genera: Exiguobacterium (CrMFC1, Acinetobacter (CrMFC2, Aeromonas (CrMFC3 and CrMFC5 and Serratia (CrMFC4. All isolates showed electrogenic activity and ability to reduce hexavalent chromium; the Acinetobacter CrMFC1 strain showed the best electrochemical performance registering a maximum power density of 18.61 mW/m2; the other strains showed values of maximum power density between 4.6 mW/m2and 7.1 mW/m2. Strains Aeromonas CrMFC5 and Exiguobacterium CrMFC1 showed the best rates of chromium reduction being able to reduce 100 % of the Cr (VI in less than 24 hours, the Aeromonas CrMFC5 strain was the most efficient, reducing 100 % of Cr (VI in 10 hours; the other strains reduced 100% of the contaminant after 28 to 30 hours. The microorganisms isolated in this study are hardly known for their electrogenic capacity and for reducing Cr (VI; however, show promise for their use in combined systems involving energy production system coupled to bioremediation of chromium contaminated water.

Optimization of shell-and-tube heat exchangers conforming to TEMA standards with designs motivated by constructal theory

International Nuclear Information System (INIS)

Yang, Jie; Fan, Aiwu; Liu, Wei; Jacobi, Anthony M.

2014-01-01

Highlights: • A design method of heat exchangers motivated by constructal theory is proposed. • A genetic algorithm is applied and the TEMA standards are rigorously followed. • Three cases are studied to illustrate the advantage of the proposed design method. • The design method will reduce the total cost compared to two other methods. - Abstract: A modified optimization design approach motivated by constructal theory is proposed for shell-and-tube heat exchangers in the present paper. In this method, a shell-and-tube heat exchanger is divided into several in-series heat exchangers. The Tubular Exchanger Manufacturers Association (TEMA) standards are rigorously followed for all design parameters. The total cost of the whole shell-and-tube heat exchanger is set as the objective function, including the investment cost for initial manufacture and the operational cost involving the power consumption to overcome the frictional pressure loss. A genetic algorithm is applied to minimize the cost function by adjusting parameters such as the tube and shell diameters, tube length and tube arrangement. Three cases are studied which indicate that the modified design approach can significantly reduce the total cost compared to the original design method and traditional genetic algorithm design method

[Effects of copper on biodegradation mechanism of trichloroethylene by mixed microorganisms].

Science.gov (United States)

Gao, Yanhui; Zhao, Tiantao; Xing, Zhilin; He, Zhi; Zhang, Lijie; Peng, Xuya

2016-05-25

We isolated and enriched mixed microorganisms SWA1 from landfill cover soils supplemented with trichloroethylene (TCE). The microbial mixture could degrade TCE effectively under aerobic conditions. Then, we investigated the effect of copper ion (0 to 15 μmol/L) on TCE biodegradation. Results show that the maximum TCE degradation speed was 29.60 nmol/min with 95.75% degradation when copper ion was at 0.03 μmol/L. In addition, genes encoding key enzymes during biodegradation were analyzed by Real-time quantitative reverse transcription PCR (RT-qPCR). The relative expression abundance of pmoA gene (4.22E-03) and mmoX gene (9.30E-06) was the highest when copper ion was at 0.03 μmol/L. Finally, we also used MiSeq pyrosequencing to investigate the diversity of microbial community. Methylocystaceae that can co-metabolic degrade TCE were the dominant microorganisms; other microorganisms with the function of direct oxidation of TCE were also included in SWA1 and the microbial diversity decreased significantly along with increasing of copper ion concentration. Based on the above results, variation of copper ion concentration affected the composition of SWA1 and degradation mechanism of TCE. The degradation mechanism of TCE included co-metabolism degradation of methanotrophs and oxidation metabolism directly at copper ion of 0.03 μmol/L. When copper ion at 5 μmol/L (biodegradation was 84.75%), the degradation mechanism of TCE included direct-degradation and co-metabolism degradation of methanotrophs and microorganisms containing phenol hydroxylase. Therefore, biodegradation of TCE by microorganisms was a complicated process, the degradation mechanism included co-metabolism degradation of methanotrophs and bio-oxidation of non-methanotrophs.

Experimental studies of biodegradation of asphalt by microorganisms

International Nuclear Information System (INIS)

Mine, Tatsuya; Mihara, Morihiro; Ooi, Takao; Lin, Kong-hua; Kawakami, Yasushi

2000-04-01

On the geological disposal system of the radioactive wastes, the activities of the microorganisms that could degrade the asphalt might be significant for the assessment of the system performance. As the main effects of the biodegradation of the asphalt, the fluctuation of leaching behavior of the nuclides included in asphalt waste has been indicated. In this study, the asphalt biodegradation test was carried out. The microorganism of which asphalt degradation ability was comparatively higher under aerobic condition and anaerobic condition was used. The asphalt biodegradation rate was calculated and it was evaluated whether the asphalt biodegradation in this system could occur. The results show that the asphalt biodegradation rate under anaerobic and high alkali condition will be 300 times lower than under aerobic and neutral pH. (author)

Production of gaba (γ – Aminobutyric acid) by microorganisms: a review

Science.gov (United States)

Dhakal, Radhika; Bajpai, Vivek K.; Baek, Kwang-Hyun

2012-01-01

GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has the possibility of providing new health-benefited products enriched with GABA. Synthesis of GABA is catalyzed by glutamate decarboxylase, therefore, the optimal fermentation condition is mainly based on the biochemical properties of the enzyme. Major GABA producing microorganisms are lactic acid bacteria (LAB), which make food spoilage pathogens unable to grow and act as probiotics in the gastrointestinal tract. The major factors affecting the production of GABA by microbial fermentation are temperature, pH, fermentation time and different media additives, therefore, these factors are summarized to provide the most up-dated information for effective GABA synthesis. There has been a huge accumulation of knowledge on GABA application for human health accompanying with a demand on natural GABA supply. Only the GABA production by microorganisms can fulfill the demand with GABA-enriched health beneficial foods. PMID:24031948

Addition of waste and introduction of microorganisms after 45 years of soil degradation

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Adriana Avelino Santos

Full Text Available ABSTRACT The construction of hydroelectric power plants (HPP may result in environmental problems, such as extensive areas of exposed subsoil and conditions of extreme degradation. These areas require alternative that minimize impact and allow partial recovery of their ecosystem functions and vegetation. This study aimed to evaluate the effects of residue addition (organic/macrophytes - OR and inorganic/ash - AR, hydrogel, and inoculation of microorganisms in degraded soil, cultivated with Jatropha curcas, through fertility and microbial activity. A conserved Cerrado ("savannah" soil was the source of microorganisms - mainly mycorrhizal fungi. The experiment was conducted for 12 months (during 2010/2011 at the farm of UNESP-School of Engineering/Campus of Ilha Solteira, Selvíria-MS, Brazil, installed in an area where the soil was degraded during the HPP construction, in the 1960s. The experimental design was complete randomized blocks, using a 2×2×4 factorial scheme, i.e., two inoculation treatments (with and without, two hydrogel treatments (with and without, and four residue treatments to introduce the J. curcas (OR, AR, OR + AR, and control without residues, with four replicates and five plants evaluated per replicate. The soil fertility analyses, quantification of microbial biomass carbon (MBC, and released C as CO2 (CO2-C, microbial quotient (qMic, and metabolic quotient (qCO2 were carried out 12 months after planting. The fertility positively responded to the addition of OR and OR + AR, with an increase in pH and SB and reduction in Al and H + Al. The inoculation of soil microorganisms associated with OR and OR + AR residue treatments raised the released CO2-C, MBC, and qMic. The addition of hydrogel combined with OR treatment contributed to the increase in the values of MBC and qMic.

Theories and Applications of Massive Online Open Courses (MOOCs): The Case for Hybrid Design

Science.gov (United States)

Anders, Abram

2015-01-01

Initial studies of learning in massive open online courses (MOOCs) primarily focused on participation patterns and participant experiences. More recently, research has addressed learning theories and offered case studies of different pedagogical designs for MOOCs. Based on a meta-analysis and synthesis of the research literature, this study…

Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

Science.gov (United States)

Kowalska, Katarzyna; Felis, Ewa

2015-01-01

Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively.

Pore-level flow, transport, agglomeration, and reaction kinetics of microorganisms

International Nuclear Information System (INIS)

Fauci, L.; Gaver, D.; Moore, P.; Papadopoulos, K.; Sharma, B.

1993-01-01

The overall goal of this research project is to improve the characterization and assessment techniques currently being used to evaluate bioremediation alternatives. This will be accomplished by investigating the phenomena and processes that affect the fate and transport of pollutants and microorganisms at the microscopic level. The specific research objectives are: Quantify the physical constants relevant to the interfacial adsorption of bacteria; Examine the bacteriological properties associated with the bioremediation of a toxin using a microscopic viewpoint; and Determine the detailed pore-level behavior of contaminants and microorganisms in a system with adsorbed contamination

Biobased production of alkanes and alkenes through metabolic engineering of microorganisms

OpenAIRE

Kang, Min Kyoung; Nielsen, Jens

2017-01-01

Advancement in metabolic engineering of microorganisms has enabled bio-based production of a range of chemicals, and such engineered microorganism can be used for sustainable production leading to reduced carbon dioxide emission there. One area that has attained much interest is microbial hydrocarbon biosynthesis, and in particular, alkanes and alkenes are important high-value chemicals as they can be utilized for a broad range of industrial purposes as well as ?drop-in? biofuels. Some microo...

Effects of a vinasse-microorganism blend application on a Vertisol with sugarcane

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Gallego Blanco Jose Miller

2012-04-01

Full Text Available

The effect of a second dose of vinasse on some physical and chemical properties of a Vertisol was evaluated with cut sugarcane in Valle del Cauca, Colombia. We analyzed the expression of any possible toxicity in foliar tissue samples at the end of the cycle. Vinasse treatments added with two different mixtures of microorganisms were established in a randomized complete block with five replicates: soil without vinasse and no microorganisms; soils with a dose of vinasse, soils with two doses of vinasse; soils with a single dose of vinasse separately evaluated with two different mixtures of microorganisms and soils with two doses of vinasse separately evaluated with two different mixtures of microorganisms. The chemical properties evaluated were pH, soil organic matter content, C, N, P, Ca, Mg, Na, and K content, cation exchange capacity CEC and electrical conductivity EC. The physical properties determined were bulk density, particle density and porosity. There were no significant differences in the physical and chemical properties of the soil for the evaluated cultivation cycle with the application of one or two doses of vinasse with and without microorganisms. Leaf tissue analysis did not show a nutritional imbalance due to the second application.

Surfactant producing TNT-degrading microorganisms for bioremediation

Energy Technology Data Exchange (ETDEWEB)

Vorobyov, A.; Marchenko, A.; Rudneva, O.; Borovick, R. [Research Center for Toxicology and Hygienic Regulation of Biopreparations, Serpukhov, Moscow region (Russian Federation); Radosevich, M. [Univ. of Delaware, Newark (United States). Dept. of Plant and Soil Sciences

2003-07-01

In general the biodegradation of nitroaromatic hydrocarbons is influenced by their bioavailability. 2,4,6-trinitrotoluene is very poorly soluble in water. TNT is easily adsorbed to clay or humus fractions in the soil, and pass very slowly to the aqueous phase, where microorganisms metabolize it. Biosurfactants that increase TNT solubility and improve its bioavailability can thereby accelerate degradation. Pure cultures of microorganisms-TNT degraders were isolated by the method of enrichment cultures from samples of different-type soil contaminated by TNT (soddy-podzol, black earth, and gray forest ones). From 28 soil samples 35 isolates of microorganisms degrading TNT were taken. The isolated soil samples had been tested for availability of microbial activity towards TNT. By10 g of air-dried soil, 10 ml of distilled water, and 2 mg of TNT were placed into 750 ml shaken flasks. The flasks were incubated at 150 rev/min and 24 C. Glucose, sodium succinate or sodium acetate had been used as co-substrates. The ability of the strains to produce surfactants was studied by drop collapsing test and direct measuring of surface tension of cultural liquid after cultivation with TNT. Cells of the strains were cultivated on solid and liquid nutrient media. For drop collapsing test the cells were cultivated on solid nutrient media; the separated colonies were suspended in distilled water. Drop sustainability test ws conducted on a standard 96-well plates coated with a thin layer of vaseline oil. Surface tension of cultural liquid ws measured after cultivation of strains in the presence of TNT with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. (orig.)

Extremely Thermophilic Microorganisms as Metabolic Engineering Platforms for Production of Fuels and Industrial Chemicals

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Benjamin M Zeldes

2015-11-01

Full Text Available Enzymes from extremely thermophilic microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely thermophilic metabolic engineering platforms are considered with an eye towards potential technological

Extremely thermophilic microorganisms as metabolic engineering platforms for production of fuels and industrial chemicals

Science.gov (United States)

Zeldes, Benjamin M.; Keller, Matthew W.; Loder, Andrew J.; Straub, Christopher T.; Adams, Michael W. W.; Kelly, Robert M.

2015-01-01

Enzymes from extremely thermophilic microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus, and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely thermophilic metabolic engineering platforms are considered with an eye toward potential technological advantages for high

Nutrition quality test of fermented waste vegetables by bioactivator local microorganisms (MOL) and effective microorganism (EM4)

Science.gov (United States)

Mirwandono, E.; Sitepu, M.; Wahyuni, T. H.; Hasnudi; Ginting, N.; Siregar, G. AW; Sembiring, I.

2018-02-01

Livestock feed mostly used waste which has low nutrition content and one way to improve feed content by fermentation. The objective of this study was to evaluate the effect of bioactifator types on fermented vegetables waste for animal feed.The research was conducted in Nutrition and Animal Feed Laboratory, Universitas Sumatera Utara from May until July 2016. The research was factorial completely randomized design of 3 x 3 with 3 replications. Factor I were bioactivator types which were control, local bioactivator and EM4 (Effective Microorganisms 4). Factor II were time of incubation 3, 5 and 7 days. Parameters were moisture content, ash, Nitrogen Free Extract (NFE) and Total Digestible Nutrient (TDN). The results showed that bioactivator types either local activator or EM4 has highly significantly different effect (P<0,01) on water content, NFE and TDN on vegetables waste while there was no different between local bioactifator with EM4 on all parameters. Time of incubation 7 days has highly significantly different effect (P<0,01) on NFE, TDN and significant different (P<0,05) on water content and ash. In conclusion local bioactifators could improve animal feed by fermenting vegetables waste and it is more available for livestockers.

The Experimental Research on E-Learning Instructional Design Model Based on Cognitive Flexibility Theory

Science.gov (United States)

Cao, Xianzhong; Wang, Feng; Zheng, Zhongmei

The paper reports an educational experiment on the e-Learning instructional design model based on Cognitive Flexibility Theory, the experiment were made to explore the feasibility and effectiveness of the model in promoting the learning quality in ill-structured domain. The study performed the experiment on two groups of students: one group learned through the system designed by the model and the other learned by the traditional method. The results of the experiment indicate that the e-Learning designed through the model is helpful to promote the intrinsic motivation, learning quality in ill-structured domains, ability to resolve ill-structured problem and creative thinking ability of the students.

Effect of the enriched filter pie with natural phosphate and microorganisms on soil and plant in a Vermelho-Distrófico Latossolo

Directory of Open Access Journals (Sweden)

Leónides Castellanos González

2016-03-01

Full Text Available The objective of the research was to evaluate the use of filter pie and phosphate rock enriched with biofertilizer microorganisms on the population of microorganisms and phosphorus tenor in the soil and on plants. The experiment was conducted in a vegetation house with corn plants with Latossolo Red-Distrófico, containing seven treatments disposed in an entirely randomized design, where the treatments were: soil samples and filter pie with additions of phosphate of Araxá rock enriched with microorganisms coming from Biopack (1, Embrafos (2 and Azotofos (3, and without enrichment with microorganisms (4, and three controls, soil just with filter pie (5, soil just with phosphate rock (6 and only soil (7, with three repetitions. Height, stem diameter and number of leaves for plants were evaluated at 14, 28 and 42 days. At the 45 days the dry matters of leafs and roots were evaluated, as the same as populations of the microorganisms and phosphorus tenor in the soil and in the aerial part of the plant. The tenor of soluble phosphorus in the soil and accumulated phosphorous in the aerial part of corn plan were increased by the treatments with filter pie but not higher with filter pie enriched with biofertilizers, so its use isn’t justified. The pie treatments increase the fungus, total and solubilizers bacterial populations in the soil, provoking an increase of the height, diameter, number of leaves and dry matter of corn plants in a Red-Distrófico Latossolo.

Conspiracy Theory

DEFF Research Database (Denmark)

Bjerg, Ole; Presskorn-Thygesen, Thomas

2017-01-01

The paper is a contribution to current debates about conspiracy theories within philosophy and cultural studies. Wittgenstein’s understanding of language is invoked to analyse the epistemological effects of designating particular questions and explanations as a ‘conspiracy theory......’. It is demonstrated how such a designation relegates these questions and explanations beyond the realm of meaningful discourse. In addition, Agamben’s concept of sovereignty is applied to explore the political effects of using the concept of conspiracy theory. The exceptional epistemological status assigned...... to alleged conspiracy theories within our prevalent paradigms of knowledge and truth is compared to the exceptional legal status assigned to individuals accused of terrorism under the War on Terror. The paper concludes by discussing the relation between conspiracy theory and ‘the paranoid style...

Strengthening the Link between Theory and Practice in Teaching Design Engineering: An Empirical Study on a New Approach

Science.gov (United States)

Tempelman, E.; Pilot, A.

2011-01-01

In 2007, the Faculty of Industrial Design Engineering of the Delft University of Technology introduced a new bachelor program. Based on theories of learning and instruction three design principles were used to develop an approach that aims to make it easier for students to bridge the gap between theoretical design engineering courses and practical…

Food Microbiology--Design and Testing of a Virtual Laboratory Exercise

Science.gov (United States)

Flint, Steve; Stewart, Terry

2010-01-01

A web-based virtual laboratory exercise in identifying an unknown microorganism was designed for use with a cohort of 3rd-year university food-technology students. They were presented with a food-contamination case, and then walked through a number of diagnostic steps to identify the microorganism. At each step, the students were asked to select 1…

Earthworm-microorganism interactions: a strategy to stabilize domestic wastewater sludge.

Science.gov (United States)

Zhao, Limin; Wang, Yayi; Yang, Jian; Xing, Meiyan; Li, Xiaowei; Yi, Danghao; Deng, Dehan

2010-04-01

The performance of a conventional biofilter (BF) and a vermifilter containing the earthworm, Eisenia foetida, (VF) for the treatment of domestic wastewater sludge were compared with the earthworm-microorganism interaction mechanisms involved in sludge stabilization. The results revealed that the presence of earthworms in the VF led to significant stabilization of the sludge by enhancing the reduction in volatile suspended solids (VSS) by 25.1%. Digestion by earthworms and the earthworm-microorganism interactions were responsible for 54% and 46% of this increase, respectively. Specifically, earthworms in the VF were capable of transforming insoluble organic materials to a soluble form and then selectively digesting the sludge particles of 10-200 microm to finer particles of 0-2 microm, which led to the further degradation of organic materials by the microorganisms in the reactor. Additionally, denaturing gradient gel electrophoresis (DGGE) profiles showed that there was an intensified bacterial diversity in the vermifilter due to the presence of earthworms, especially in response to the nutrients in their casts. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Systems Biology of Industrial Microorganisms

Science.gov (United States)

Papini, Marta; Salazar, Margarita; Nielsen, Jens

The field of industrial biotechnology is expanding rapidly as the chemical industry is looking towards more sustainable production of chemicals that can be used as fuels or building blocks for production of solvents and materials. In connection with the development of sustainable bioprocesses, it is a major challenge to design and develop efficient cell factories that can ensure cost efficient conversion of the raw material into the chemical of interest. This is achieved through metabolic engineering, where the metabolism of the cell factory is engineered such that there is an efficient conversion of sugars, the typical raw materials in the fermentation industry, into the desired product. However, engineering of cellular metabolism is often challenging due to the complex regulation that has evolved in connection with adaptation of the different microorganisms to their ecological niches. In order to map these regulatory structures and further de-regulate them, as well as identify ingenious metabolic engineering strategies that full-fill mass balance constraints, tools from systems biology can be applied. This involves both high-throughput analysis tools like transcriptome, proteome and metabolome analysis, as well as the use of mathematical modeling to simulate the phenotypes resulting from the different metabolic engineering strategies. It is in fact expected that systems biology may substantially improve the process of cell factory development, and we therefore propose the term Industrial Systems Biology for how systems biology will enhance the development of industrial biotechnology for sustainable chemical production.

Designing molecular complexes using free-energy derivatives from liquid-state integral equation theory

International Nuclear Information System (INIS)

Mrugalla, Florian; Kast, Stefan M

2016-01-01

Complex formation between molecules in solution is the key process by which molecular interactions are translated into functional systems. These processes are governed by the binding or free energy of association which depends on both direct molecular interactions and the solvation contribution. A design goal frequently addressed in pharmaceutical sciences is the optimization of chemical properties of the complex partners in the sense of minimizing their binding free energy with respect to a change in chemical structure. Here, we demonstrate that liquid-state theory in the form of the solute–solute equation of the reference interaction site model provides all necessary information for such a task with high efficiency. In particular, computing derivatives of the potential of mean force (PMF), which defines the free-energy surface of complex formation, with respect to potential parameters can be viewed as a means to define a direction in chemical space toward better binders. We illustrate the methodology in the benchmark case of alkali ion binding to the crown ether 18-crown-6 in aqueous solution. In order to examine the validity of the underlying solute–solute theory, we first compare PMFs computed by different approaches, including explicit free-energy molecular dynamics simulations as a reference. Predictions of an optimally binding ion radius based on free-energy derivatives are then shown to yield consistent results for different ion parameter sets and to compare well with earlier, orders-of-magnitude more costly explicit simulation results. This proof-of-principle study, therefore, demonstrates the potential of liquid-state theory for molecular design problems. (paper)

isolation and identification of the microorganisms most prevalent

African Journals Online (AJOL)

problems presenting in eye clinics on a daily basis. With one or two ... microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of sterile .... through personal contacts. Consequently, the.

Isolation of radioresistant microorganisms from a Co/sup 60/ irradiation plant

International Nuclear Information System (INIS)

Lezcano, Graciela

1982-01-01

The continuos exposition to low doses of gamma irradiation can produce changes in the microflora's radioresistance. In order to obtain information about these possible modifications, the water from the pool used as shielding of the source, as well as the air and the dust in the irradiation chamber of the semi-industrial irradiation plant existing at the Ezeiza Atomic Center were analyzed. The number of microorganisms was determined by filtration techniques and by dilutions. Radioresistance studies of the contaminating microflora were performed. The value of the D/sub 10/ dose was determined in the conditions of highest resistance. A pronounced decrease in the number of microorganisms was observed as a radiation effect in the samples of water and dust, but not in the air samples, this as a consequence of the extractors' action that continually renews the air and the flora in the chamber, thus preventing high-dose exposure. In the air samples no increase of the microorganisms' radioresistance was observed. In the pool water flora, the development of a great radioresistance was observed. A microorganism whose inactivation curve shows a shoulder of 3.2 Mrad was isolated. This high radioresistance could be the result of the continous exposure to low doses during six years. Contrarily, the microorganims of the irradiation chamber's dust did not increase their radioresistance wiht regard to the common contaminants. In the flora of the dust used as a target, two microorganims whose D/sub 10/ were in excess of 400 krad were found; these could be ocassional contaminants. The radioresistant microorganims were isolated and characterized according to Cowan's scheme, the water microorganisms being identified as belonging to the genus Corynebacterium and the earth ones to the genera Micrococcus and Corynebacterium. (author) [es

[Update views on the theory of phagocytosis].

Science.gov (United States)

Freĭdlin, I S

2008-01-01

Developer of the phagocytosis theory I.I Mechnikov forecasted the most fruitful directions of its development. Macrophages express on the plasma membranes broad spectrum of receptors, which mediate their interaction with altered organism's own components as well as with exogenous agents, including various microorganisms. Recognition leads to changes of expression of surface molecules, enhancement of phagocytic activity as well as production and secretion of cytokines, presentation functions, signaling and genes expression. This reflected on maintenance of homeostasis, as well as on host defense effectiveness, including mechanisms of innate and adaptive immunity.

The hydrodynamics of swimming microorganisms

International Nuclear Information System (INIS)

Lauga, Eric; Powers, Thomas R

2009-01-01

Cell motility in viscous fluids is ubiquitous and affects many biological processes, including reproduction, infection and the marine life ecosystem. Here we review the biophysical and mechanical principles of locomotion at the small scales relevant to cell swimming, tens of micrometers and below. At this scale, inertia is unimportant and the Reynolds number is small. Our emphasis is on the simple physical picture and fundamental flow physics phenomena in this regime. We first give a brief overview of the mechanisms for swimming motility, and of the basic properties of flows at low Reynolds number, paying special attention to aspects most relevant for swimming such as resistance matrices for solid bodies, flow singularities and kinematic requirements for net translation. Then we review classical theoretical work on cell motility, in particular early calculations of swimming kinematics with prescribed stroke and the application of resistive force theory and slender-body theory to flagellar locomotion. After examining the physical means by which flagella are actuated, we outline areas of active research, including hydrodynamic interactions, biological locomotion in complex fluids, the design of small-scale artificial swimmers and the optimization of locomotion strategies.

Ionic liquid-tolerant microorganisms and microbial communities for lignocellulose conversion to bioproducts.

Science.gov (United States)

Yu, Chaowei; Simmons, Blake A; Singer, Steven W; Thelen, Michael P; VanderGheynst, Jean S

2016-12-01

Chemical and physical pretreatment of biomass is a critical step in the conversion of lignocellulose to biofuels and bioproducts. Ionic liquid (IL) pretreatment has attracted significant attention due to the unique ability of certain ILs to solubilize some or all components of the plant cell wall. However, these ILs inhibit not only the enzyme activities but also the growth and productivity of microorganisms used in downstream hydrolysis and fermentation processes. While pretreated biomass can be washed to remove residual IL and reduce inhibition, extensive washing is costly and not feasible in large-scale processes. IL-tolerant microorganisms and microbial communities have been discovered from environmental samples and studies begun to elucidate mechanisms of IL tolerance. The discovery of IL tolerance in environmental microbial communities and individual microbes has lead to the proposal of molecular mechanisms of resistance. In this article, we review recent progress on discovering IL-tolerant microorganisms, identifying metabolic pathways and mechanisms of tolerance, and engineering microorganisms for IL tolerance. Research in these areas will yield new approaches to overcome inhibition in lignocellulosic biomass bioconversion processes and increase opportunities for the use of ILs in biomass pretreatment.

Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

African Journals Online (AJOL)

Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

Novel Industrial Enzymes from Uncultured Arctic Microorganisms

DEFF Research Database (Denmark)

Vester, Jan Kjølhede

, and reduce the risk of contaminations. Cold- and alkaline-active enzymes can be found in microorganisms adapted to living in natural environments with these conditions, which are extremely rare but found in the unique ikaite columns from SW Greenland (4-6 °C, pH >10). It is estimated that less than 1...

MICROORGANISMS ANTIBIOTIC SENSITIVITY DETERMINATION IN URINARY TRACT INFECTIONS

Directory of Open Access Journals (Sweden)

Shapovalova O.V.

2016-06-01

Full Text Available Introduction. Nowadays Urinary tract infections (UTI are considered to be the most common bacterial infections. Escherichia coli is the most frequently uropathogen. Other microorganisms of the genera Enterococcus, Klebsiella, Enterobacter, Proteus, Morganella, Citrobacter, Serratia, Pseudomonas, Streptococcus, Staphylococcus, Candida are also isolated with variable frequency. In recent years there has been a decreasing tendency of the causative agents of UTI sensitivity to various antibiotics, which causes growth of an inefficiency treatment risk. In connection with the above the investigations were carried out with the purpose to identify the actual causative agents of bacteriuria and their sensitivity to antibiotics and antifungal drugs. Materials and methods. Bacteriological examination of urine was performed at 42 patients of SI "Sytenko Institute of Spine and Joint Pathology, AMS of Ukraine" clinic. The bacteriological method for determining the number of bacteria in the test material, cultural and bacterioscopic methods for identifying microorganisms and disk-diffusion method for sensitivity of microorganisms to antibiotics determining were used. The clinical material for the study was an average portion of the morning urine or urine collected by catheter. The biological material collection and bacteriological examination was carried by quantitative method, the isolated microorganisms identification and their sensitivity to antibiotics determining was performed by standard methods in accordance with current guidelines. We used the following antibiotics group to determine the microorganisms sensitivity: penicillin, cephalosporin, karbapenems, tetracyclines, aminoglycoside, fluoroquinolones, oxazolidinones, macrolides, lincosamides, glycopeptides, antifungal antibiotics. Results and discussion. During the biological material study 55 isolates of bacterial and fungal pathogens were obtained. The microorganisms’ concentration in urine was in

[Evolution of pathogenic micro-organisms as a challenge for medicine].

Science.gov (United States)

Vaara, Martti

2009-01-01

Successful parasitic micro-organisms are able to adapt to the circumstances of the host's organ system, and it is usually not expedient for them to kill their host. Under selection pressure, the evolution of micro-organisms is vastly quicker that that of man. The selection pressure brought about by rapid ecological changes and alterations associated with human action provides for the development of new, dangerous pathogens and transformation of familiar pathogens to become more dangerous. Progress in molecular biology has thus far not yielded as many new tools for the treatment of infectious diseases as the hopes were in the early 2000's.

Transfer Rates of Enteric Microorganisms in Recycled Water during Machine Clothes Washing▿

Science.gov (United States)

O'Toole, Joanne; Sinclair, Martha; Leder, Karin

2009-01-01

Approximately 15% of overall Australian household water usage is in the laundry; hence, a significant reduction in household drinking water demand could be achieved if potable-quality water used for clothes washing is replaced with recycled water. To investigate the microbiological safety of using recycled water in washing machines, bacteriophages MS-2 and PRD-1, Escherichia coli, and Cryptosporidium parvum oocysts were used in a series of experiments to investigate the transfer efficiency of enteric microorganisms from washing machine water to objects including hands, environmental surfaces, air, and fabric swatches. By determining the transference efficiency, it is possible to estimate the numbers of microorganisms that the user will be exposed to if recycled water with various levels of residual microorganisms is used in washing machines. Results, expressed as transfer rates to a given surface area per object, showed that the mean transfer efficiency of E. coli, bacteriophages MS-2 and PRD-1, and C. parvum oocysts from seeded water to fabric swatches ranged from 0.001% to 0.090%. Greatest exposure to microorganisms occurred through direct contact of hands with seeded water and via hand contact with contaminated fabric swatches. No microorganisms were detected in the air samples during the washing machine spin cycle, and transfer rates of bacteriophages from water to environmental surfaces were 100-fold less than from water directly to hands. Findings from this study provide relevant information that can be used to refine regulations governing recycled water and to allay public concerns about the use of recycled water. PMID:19124592

Machine learning in the rational design of antimicrobial peptides.

Science.gov (United States)

Rondón-Villarreal, Paola; Sierra, Daniel A; Torres, Rodrigo

2014-01-01

One of the most important public health issues is the microbial and bacterial resistance to conventional antibiotics by pathogen microorganisms. In recent years, many researches have been focused on the development of new antibiotics. Among these, antimicrobial peptides (AMPs) have raised as a promising alternative to combat antibioticresistant microorganisms. For this reason, many theoretical efforts have been done in the development of new computational tools for the rational design of both better and effective AMPs. In this review, we present an overview of the rational design of AMPs using machine learning techniques and new research fields.

Activity-Based Design as a Way to Bridge Artifacts, Professions, and Theories

DEFF Research Database (Denmark)

Brynskov, Martin

2007-01-01

This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe the conditi......, informational, and pragmatic – together with the ability to describe their relations are a useful platform for practitioners and theorists who are forced to span a heterogeneous mash-up of technologies, theories, and professions.......This paper will focus on the challenges in designing pervasive computing technology for children’s play, taking into account current trends in popular culture. In search of theoretical support for this work I have been exploring an activity-based approach called ‘habitats’ to describe...

A Comparative Evaluation of Adherence of Microorganism to Different Types of Brackets: A Scanning Electron Microscopic Study.

Science.gov (United States)

Shashidhar, E P; Sahitya, M; Sunil, T; Murthy, Anup R; Rani, M S

2015-09-01

The purpose of this study was to evaluate and compare the adherence of microorganism to different types of brackets using the scanning electron microscope (SEM). A double-blinded study was undertaken to evaluate and adherence of microorganisms to different types of brackets using SEM. At random, 12 patients reporting for treatment to the department of Orthodontics VS Dental College and Hospital were selected. Four types of brackets were included in the present study stainless steel, titanium, composite, and ceramic. Brackets were bonded to teeth of the patient on all the four quadrants. The teeth included for bonding were lateral incisor, canine, first premolar, and second premolar. The brackets were left for 72 h. After 72 h brackets were debonded, and they were evaluated by SEM for adherence of microorganism in the slot and tie wings surface. The SEM images were graded, and the adherence of microorganism to the brackets in the surfaces and the four different quadrants were recorded. There is a significant difference in adherence of microorganisms to the various types of brackets (P 0.05) included in the study. The interaction of bracket/surface, bracket/quadrant, surface/quadrants was analyzed, there was no significance of comparison of bracket/surfaces/quadrant but the interaction of bracket/quadrant was found to be significant (bracket/surfaces/quadrant was also found to be significant (bracket material and the least adherence of microorganisms was observed with the titanium bracket material. The adherence of microorganisms is relatively more in the slot area, when compare to the tie wings surface maximum adherence of microorganism is observed in the upper left quadrant and least adherence of microorganism is observed in the lower right quadrant. There is a significant difference in adherence of microorganisms to various types of brackets and the surfaces included in the study. There is no significant difference in the adherence of microorganism to the bracket

Distribution of microorganisms in herb medicines and their decontamination by gamma-irradiation

International Nuclear Information System (INIS)

Ito, Hitoshi

1999-01-01

Herb medicines are traditional medicine in Japan and have been used for medical treatment. These herb medicines are contaminating frequently by microorganisms which has possibility to cause opportunistic diseases. Recently, hygienic standard of herb medicines become more strict than before, and it needs to decontaminate microorganisms by some treatments. However, chemical treatments such as by ethylene oxide fumigation leave toxic residues in the herbs while steam sterilization decease medicinal components. From study on the distribution of microorganisms in 31 samples of selected herb medicines, colony forming units of total aerobic bacteria were determined to be l.9 x 10 2 to l.4 x 10 8 per gram in 30 samples. Coliforms were also determined to be 6.9 x 10 2 to 4.3 x 10 6 per gram in 16 samples. The main aerobic bacteria were identified as Bacillus pumilus, B. circulans, B. megaterium, Erwinia, Enterobacter and Acinetobacter, whereas consisted mainly of Enterobacter in coliform counts. Molds were determined to be 6.3 x 10 1 to 1.9 x 10 5 per gram which consisted mainly Aspergillus glaucus group, A. restrictus group, A. flavus group, A. ostianus, A. phoenicis, Penicillium, Tricoderma, Rhizopus and Alternaria in 25 samples. A study on the inactivation of microorganisms at sample No. S18 showed that a gamma-irradiation dose of 20 kGy was required to reduce the total aerobic bacteria and the coliforms below a detectable level, while radiation-resistant bacteria were survived at high doses more than 10 kGy consisted with Acinetobacter and Enterobacter. Molds were inactivated below 8 kGy except Alternaria. However, a dose of 10 kGy should be effective for the sample No. S18 to reduce the spore-forming bacteria, the fecal coliforms and the molds below a detectable level per gram. On the study of inactivation of microorganisms in many samples except the No. 18, all kinds of microorganism were inactivated below a detectable level at 10 kGy irradiation. (author)

Distribution of microorganisms in herb medicines and their decontamination by gamma-irradiation

Energy Technology Data Exchange (ETDEWEB)

Ito, Hitoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Kamakura, Hiroyuki; Sekita, Setuko [National Institute of Health Sciences, Kamiyoga, Tokyo (Japan)