Syntrophic interactions and mechanisms underpinning anaerobic methane oxidation: targeted metaproteogenomics, single-cell protein detection and quantitative isotope imaging of microbial consortia

Energy Technology Data Exchange (ETDEWEB)

Orphan, Victoria Jeanne [California Inst. of Technology (CalTech), Pasadena, CA (United States). Division of Geological and Planetary Sciences

2014-11-26

Syntrophy and mutualism play a central role in carbon and nutrient cycling by microorganisms. Yet, our ability to effectively study symbionts in culture has been hindered by the inherent interdependence of syntrophic associations, their dynamic behavior, and their frequent existence at thermodynamic limits. Now solutions to these challenges are emerging in the form of new methodologies. Developing strategies that establish links between the identity of microorganisms and their metabolic potential, as well as techniques that can probe metabolic networks on a scale that captures individual molecule exchange and processing, is at the forefront of microbial ecology. Understanding the interactions between microorganisms on this level, at a resolution previously intractable, will lead to our greater understanding of carbon turnover and microbial community resilience to environmental perturbations. In this project, we studied an enigmatic syntrophic association between uncultured methane-oxidizing archaea and sulfate-reducing bacteria. This environmental archaeal-bacterial partnership represents a globally important sink for methane in anoxic environments. The specific goals of this project were organized into 3 major tasks designed to address questions relating to the ecophysiology of these syntrophic organisms under changing environmental conditions (e.g. different electron acceptors and nutrients), primarily through the development of microanalytical imaging methods which enable the visualization of the spatial distribution of the partners within aggregates, consumption and exchange of isotopically labeled substrates, and expression of targeted proteins identified via metaproteomics. The advanced tool set developed here to collect, correlate, and analyze these high resolution image and isotope-based datasets from methane-oxidizing consortia has the potential to be widely applicable for studying and modeling patterns of activity and interactions across a broad range of

Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

DEFF Research Database (Denmark)

Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

Substrates that contain high ammonia levels can cause inhibition on anaerobic digestion process and unstable biogas production. The aim of the current study was to assess the effects of different ammonia levels on pure strains of (syntrophic acetate oxidizing) SAO bacteria and hydrogenotrophic...... methanogens. Two pure strains of hydrogenotrophic methanogens (i.e: Methanoculleus bourgensis and Methanoculleus thermophiles) and two pure strains of SAO bacteria (i.e: Tepidanaerobacter acetatoxydans and Thermacetogenium phaeum) were inoculated under four different ammonia (0.26, 3, 5 and 7g NH4+-N......, the total incubation periods of hydrogenotrophic methanogens were significantly shorter compared to the SAO bacteria incubation periods. Thus, it seems that hydrogenotrophic methanogens could be equally, if not more, tolerant to high ammonia levels compared to SAO bacteria....

Syntrophic interactions drive the hydrogen production from glucose at low temperature in microbial electrolysis cells

KAUST Repository

Lu, Lu

2012-11-01

H2 can be obtained from glucose by fermentation at mesophilic temperatures, but here we demonstrate that hydrogen can also be obtained from glucose at low temperatures using microbial electrolysis cells (MECs). H2 was produced from glucose at 4°C in single-chamber MECs at a yield of about 6mol H2mol-1 glucose, and at rates of 0.25±0.03-0.37±0.04m3 H2m-3d-1. Pyrosequencing of 16S rRNA gene and electrochemical analyses showed that syntrophic interactions combining glucose fermentation with the oxidization of fermentation products by exoelectrogens was the predominant pathway for current production at a low temperature other than direct glucose oxidization by exoelectrogens. Another syntrophic interaction, methanogenesis and homoacetogenesis, which have been found in 25°C reactors, were not detected in MECs at 4°C. These results demonstrate the feasibility of H2 production from abundant biomass of carbohydrates at low temperature in MECs. © 2012 Elsevier Ltd.

Anaerobic hydrocarbon and fatty acid metabolism by syntrophic bacteria and their impact on carbon steel corrosion

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Christopher Neil Lyles

2014-04-01

Full Text Available The microbial metabolism of hydrocarbons is increasingly associated with the corrosion of carbon steel in sulfate-rich marine waters. However, how such transformations influence metal biocorrosion in the absence of an electron acceptor is not fully recognized. We grew a marine alkane-utilizing, sulfate-reducing bacterium, Desulfoglaeba alkanexedens, with either sulfate or Methanospirillum hungatei as electron acceptors, and tested the ability of the cultures to catalyze metal corrosion. Axenically, D. alkanexedens had a higher instantaneous corrosion rate and produced more pits in carbon steel coupons than when the same organism was grown in syntrophic co-culture with the methanogen. Since anaerobic hydrocarbon biodegradation pathways converge on fatty acid intermediates, the corrosive ability of a known fatty acid-oxidizing syntrophic bacterium, Syntrophus aciditrophicus was compared when grown in pure culture or in co-culture with a H2-utilizing sulfate-reducing bacterium (Desulfovibrio sp., strain G11 or a methanogen (M. hungatei. The instantaneous corrosion rates in the cultures were not substantially different, but the syntrophic, sulfate-reducing co-culture produced more pits in coupons than other combinations of microorganisms. Lactate-grown cultures of strain G11 had higher instantaneous corrosion rates and coupon pitting compared to the same organism cultured with hydrogen as an electron donor. Thus, if sulfate is available as an electron acceptor, the same microbial assemblages produce sulfide and low molecular weight organic acids that exacerbated biocorrosion. Despite these trends, a surprisingly high degree of variation was encountered with the corrosion assessments. Differences in biomass, initial substrate concentration, rates of microbial activity or the degree of end product formation did not account for the variations. We are forced to ascribe such differences to the metallurgical properties of the coupons.

Anaerobic hydrocarbon and fatty acid metabolism by syntrophic bacteria and their impact on carbon steel corrosion.

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Lyles, Christopher N; Le, Huynh M; Beasley, William Howard; McInerney, Michael J; Suflita, Joseph M

2014-01-01

The microbial metabolism of hydrocarbons is increasingly associated with the corrosion of carbon steel in sulfate-rich marine waters. However, how such transformations influence metal biocorrosion in the absence of an electron acceptor is not fully recognized. We grew a marine alkane-utilizing, sulfate-reducing bacterium, Desulfoglaeba alkanexedens, with either sulfate or Methanospirillum hungatei as electron acceptors, and tested the ability of the cultures to catalyze metal corrosion. Axenically, D. alkanexedens had a higher instantaneous corrosion rate and produced more pits in carbon steel coupons than when the same organism was grown in syntrophic co-culture with the methanogen. Since anaerobic hydrocarbon biodegradation pathways converge on fatty acid intermediates, the corrosive ability of a known fatty acid-oxidizing syntrophic bacterium, Syntrophus aciditrophicus was compared when grown in pure culture or in co-culture with a H2-utilizing sulfate-reducing bacterium (Desulfovibrio sp., strain G11) or a methanogen (M. hungatei). The instantaneous corrosion rates in the cultures were not substantially different, but the syntrophic, sulfate-reducing co-culture produced more pits in coupons than other combinations of microorganisms. Lactate-grown cultures of strain G11 had higher instantaneous corrosion rates and coupon pitting compared to the same organism cultured with hydrogen as an electron donor. Thus, if sulfate is available as an electron acceptor, the same microbial assemblages produce sulfide and low molecular weight organic acids that exacerbated biocorrosion. Despite these trends, a surprisingly high degree of variation was encountered with the corrosion assessments. Differences in biomass, initial substrate concentration, rates of microbial activity or the degree of end product formation did not account for the variations. We are forced to ascribe such differences to the metallurgical properties of the coupons.

Genome-guided analysis of physiological capacities of Tepidanaerobacter acetatoxydans provides insights into environmental adaptations and syntrophic acetate oxidation.

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Bettina Müller

Full Text Available This paper describes the genome-based analysis of Tepidanaerobacter acetatoxydans strain Re1, a syntrophic acetate-oxidising bacterium (SAOB. Principal issues such as environmental adaptations, metabolic capacities, and energy conserving systems have been investigated and the potential consequences for syntrophic acetate oxidation discussed. Briefly, in pure culture, T. acetatoxydans grows with different organic compounds and produces acetate as the main product. In a syntrophic consortium with a hydrogenotrophic methanogen, it can also reverse its metabolism and instead convert acetate to formate/H2 and CO2. It can only proceed if the product formed is continuously removed. This process generates a very small amount of energy that is scarcely enough for growth, which makes this particular syntrophy of special interest. As a crucial member of the biogas-producing community in ammonium-rich engineered AD processes, genomic features conferring ammonium resistance, bacterial defense, oxygen and temperature tolerance were found, as well as attributes related to biofilm formation and flocculation. It is likely that T. acetatoxydans can form an electrochemical gradient by putative electron-bifurcating Rnf complex and [Fe-Fe] hydrogenases, as observed in other acetogens. However, genomic deficiencies related to acetogenic metabolism and anaerobic respiration were discovered, such as the lack of formate dehydrogenase and F1F0 ATP synthase. This has potential consequences for the metabolic pathways used under SAO and non-SAO conditions. The two complete sets of bacteriophage genomes, which were found to be encoded in the genome, are also worthy of mention.

Syntrophic growth with direct interspecies electron transfer as the primary mechanism for energy exchange

DEFF Research Database (Denmark)

Shrestha, Pravin Malla; Rotaru, Amelia-Elena; Aklujkar, Muktak

2013-01-01

Direct interspecies electron transfer (DIET) through biological electrical connections is an alternative to interspecies H2 transfer as a mechanism for electron exchange in syntrophic cultures. However, it has not previously been determined whether electrons received via DIET yield energy...... dehydrogenase, the pilus-associated c-type cytochrome OmcS and pili consistent with electron transfer via DIET. These results suggest that electrons transferred via DIET can serve as the sole energy source to support anaerobic respiration....

Bioaugmentation of Syntrophic Acetate-Oxidizing Culture in Biogas Reactors Exposed to Increasing Levels of Ammonia

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Westerholm, Maria; Levén, Lotta

2012-01-01

The importance of syntrophic acetate oxidation for process stability in methanogenic systems operating at high ammonia concentrations has previously been emphasized. In this study we investigated bioaugmentation of syntrophic acetate-oxidizing (SAO) cultures as a possible method for decreasing the adaptation period of biogas reactors operating at gradually increased ammonia concentrations (1.5 to 11 g NH4+-N/liter). Whole stillage and cattle manure were codigested semicontinuously for about 460 days in four mesophilic anaerobic laboratory-scale reactors, and a fixed volume of SAO culture was added daily to two of the reactors. Reactor performance was evaluated in terms of biogas productivity, methane content, pH, alkalinity, and volatile fatty acid (VFA) content. The decomposition pathway of acetate was analyzed by isotopic tracer experiments, and population dynamics were monitored by quantitative PCR analyses. A shift in dominance from aceticlastic methanogenesis to SAO occurred simultaneously in all reactors, indicating no influence by bioaugmentation on the prevailing pathway. Higher abundances of Clostridium ultunense and Tepidanaerobacter acetatoxydans were associated with bioaugmentation, but no influence on Syntrophaceticus schinkii or the methanogenic population was distinguished. Overloading or accumulation of VFA did not cause notable dynamic effects on the population. Instead, the ammonia concentration had a substantial impact on the abundance level of the microorganisms surveyed. The addition of SAO culture did not affect process performance or stability against ammonia inhibition, and all four reactors deteriorated at high ammonia concentrations. Consequently, these findings further demonstrate the strong influence of ammonia on the methane-producing consortia and on the representative methanization pathway in mesophilic biogas reactors. PMID:22923397

Syntrophic acetate oxidation in two-phase (acid-methane) anaerobic digesters.

Science.gov (United States)

Shimada, T; Morgenroth, E; Tandukar, M; Pavlostathis, S G; Smith, A; Raskin, L; Kilian, R E

2011-01-01

The microbial processes involved in two-phase anaerobic digestion were investigated by operating a laboratory-scale acid-phase (AP) reactor and analyzing two full-scale, two-phase anaerobic digesters operated under mesophilic (35 °C) conditions. The digesters received a blend of primary sludge and waste activated sludge (WAS). Methane levels of 20% in the laboratory-scale reactor indicated the presence of methanogenic activity in the AP. A phylogenetic analysis of an archaeal 16S rRNA gene clone library of one of the full-scale AP digesters showed that 82% and 5% of the clones were affiliated with the orders Methanobacteriales and Methanosarcinales, respectively. These results indicate that substantial levels of aceticlastic methanogens (order Methanosarcinales) were not maintained at the low solids retention times and acidic conditions (pH 5.2-5.5) of the AP, and that methanogenesis was carried out by hydrogen-utilizing methanogens of the order Methanobacteriales. Approximately 43, 31, and 9% of the archaeal clones from the methanogenic phase (MP) digester were affiliated with the orders Methanosarcinales, Methanomicrobiales, and Methanobacteriales, respectively. A phylogenetic analysis of a bacterial 16S rRNA gene clone library suggested the presence of acetate-oxidizing bacteria (close relatives of Thermacetogenium phaeum, 'Syntrophaceticus schinkii,' and Clostridium ultunense). The high abundance of hydrogen consuming methanogens and the presence of known acetate-oxidizing bacteria suggest that acetate utilization by acetate oxidizing bacteria in syntrophic interaction with hydrogen-utilizing methanogens was an important pathway in the second-stage of the two-phase digestion, which was operated at high ammonium-N concentrations (1.0 and 1.4 g/L). A modified version of the IWA Anaerobic Digestion Model No. 1 (ADM1) with extensions for syntrophic acetate oxidation and weak-acid inhibition adequately described the dynamic profiles of volatile acid production

Anaerobic oxidation of fatty acids by Clostridium bryantii sp. nov. : a sporeforming, obligately syntrophic bacterium

OpenAIRE

Stieb, Marion; Schink, Bernhard

1985-01-01

From marine and freshwater mud samples strictly anaerobic, Gram-positive, sporeforming bacteria were isolated which oxidized fatty acids in obligately syntrophic association with H2-utilizing bacteria. Even-numbered fatty acids with up to 10 carbon atoms were degraded to acetate and Hz, odd-numbered fatty acids with up to 11 carbon atoms including 2-methylbutyrate were degraded to acetate, propionate and H2. Neither fumarate, sulfate, thiosulfate, sulfur, nor nitrate were reduced. A marine is...

The quantitative significance of Syntrophaceae and syntrophic partnerships in methanogenic degradation of crude oil alkanes.

Science.gov (United States)

Gray, N D; Sherry, A; Grant, R J; Rowan, A K; Hubert, C R J; Callbeck, C M; Aitken, C M; Jones, D M; Adams, J J; Larter, S R; Head, I M

2011-11-01

Libraries of 16S rRNA genes cloned from methanogenic oil degrading microcosms amended with North Sea crude oil and inoculated with estuarine sediment indicated that bacteria from the genera Smithella (Deltaproteobacteria, Syntrophaceace) and Marinobacter sp. (Gammaproteobacteria) were enriched during degradation. Growth yields and doubling times (36 days for both Smithella and Marinobacter) were determined using qPCR and quantitative data on alkanes, which were the predominant hydrocarbons degraded. The growth yield of the Smithella sp. [0.020 g(cell-C)/g(alkane-C)], assuming it utilized all alkanes removed was consistent with yields of bacteria that degrade hydrocarbons and other organic compounds in methanogenic consortia. Over 450 days of incubation predominance and exponential growth of Smithella was coincident with alkane removal and exponential accumulation of methane. This growth is consistent with Smithella's occurrence in near surface anoxic hydrocarbon degrading systems and their complete oxidation of crude oil alkanes to acetate and/or hydrogen in syntrophic partnership with methanogens in such systems. The calculated growth yield of the Marinobacter sp., assuming it grew on alkanes, was [0.0005 g(cell-C)/g(alkane-C)] suggesting that it played a minor role in alkane degradation. The dominant methanogens were hydrogenotrophs (Methanocalculus spp. from the Methanomicrobiales). Enrichment of hydrogen-oxidizing methanogens relative to acetoclastic methanogens was consistent with syntrophic acetate oxidation measured in methanogenic crude oil degrading enrichment cultures. qPCR of the Methanomicrobiales indicated growth characteristics consistent with measured rates of methane production and growth in partnership with Smithella. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Proteomic analysis reveals metabolic and regulatory systems involved the syntrophic and axenic lifestyle of Syntrophomonas wolfei.

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Jessica Rhea Sieber

2015-02-01

Full Text Available Microbial syntrophy is a vital metabolic interaction necessary for the complete oxidation of organic biomass to methane in all-anaerobic ecosystems. However, this process is thermodynamically constrained and represents an ecosystem-level metabolic bottleneck. To gain insight into the physiology of this process, a shotgun proteomic approach was used to quantify the protein landscape of the model syntrophic metabolizer, Syntrophomonas wolfei, grown axenically and syntrophically with Methanospirillum hungatei. Remarkably, the abundance of most proteins as represented by normalized spectral abundance factor (NSAF value changed very little between the pure and coculture growth conditions. Among the most abundant proteins detected were GroEL and GroES chaperonins, a small heat shock protein, and proteins involved in electron transfer, beta-oxidation, and ATP synthesis. Several putative energy conservation enzyme systems that utilize NADH and ferredoxin were present. The abundance of an EtfAB2 and the membrane-bound iron-sulfur oxidoreductase (Swol_0698 gene product delineated a potential conduit for electron transfer between acyl-CoA dehydrogenases and membrane redox carriers. Proteins detected only when S. wolfei was grown with M. hungatei included a zinc-dependent dehydrogenase with a GroES domain, whose gene is present in genomes in many organisms capable of syntrophy, and transcriptional regulators responsive to environmental stimuli or the physiological status of the cell. The proteomic analysis revealed an emphasis macromolecular stability and energy metabolism to S. wolfei and presence of regulatory mechanisms responsive to external stimuli and cellular physiological status.

Involvement of formate as an interspecies electron carrier in a syntrophic acetate-oxidizing anaerobic microorganism in coculture with methanogens.

Science.gov (United States)

Hattori, S; Luo, H; Shoun, H; Kamagata, Y

2001-01-01

To determine whether formate is involved in interspecies electron transfer between substrate-oxidizing bacteria and hydrogenotrophic microorganisms under anaerobic conditions, a syntrophic acetate-oxidizing bacterium Thermacetogenium phaeum strain PB was cocultured either with a formate /H2-utilizing methanogen strain TM (designated as PB/TM coculture), or an H2-utilizing methanogen strain deltaH (designated as PB/deltaH coculture). Acetate oxidation and subsequent methanogenesis in PB/TM coculture were found to be significantly faster than in PB/deltaH coculture. Formate dehydrogenase and hydrogenase were both detected in strains PB and TM. H2 partial pressures in the PB/TM coculture were kept lower (20 to 40 Pa) than those of the PB/deltaH coculture (40 to 60 Pa) during the exponential growth phase. Formate was also detected in both PB/TM and PB/deltaH cocultures, and the concentration of formate was maintained at a lower level in the PB/TM coculture (5 to 9 microM) than in the PB/deltaH coculture. Thermodynamic calculations revealed that the concentrations of both H2 and formate severely affect the syntrophic oxidation of acetate. These results strongly indicate that not only H2 but also formate may be involved in interspecies electron transfer.

Syntrophic Growth via Quinone-Mediated Interspecies Electron Transfer

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Jessica A Smith

2015-02-01

Full Text Available The mechanisms by which microbial species exchange electrons are of interest because interspecies electron transfer can expand the metabolic capabilities of microbial communities. Previous studies with the humic substance analog anthraquinone-2,6-disulfonate (AQDS suggested that quinone-mediated interspecies electron transfer (QUIET is feasible, but it was not determined if sufficient energy is available from QUIET to support the growth of both species. Furthermore, there have been no previous studies on the mechanisms for the oxidation of anthrahydroquinone-2,6-disulfonate (AHQDS. A co-culture of Geobacter metallireducens and Geobacter sulfurreducens metabolized ethanol with the reduction of fumarate much faster in the presence of AQDS, and there was an increase in cell protein. G. sulfurreducens was more abundant, consistent with G. sulfurreducens obtaining electrons from acetate that G. metallireducens produced from ethanol, as well as from AHQDS. Cocultures initiated with a citrate synthase-deficient strain of G. sulfurreducens that was unable to use acetate as an electron donor also metabolized ethanol with the reduction of fumarate and cell growth, but acetate accumulated over time. G. sulfurreducens and G. metallireducens were equally abundant in these co-cultures reflecting the inability of the citrate synthase-deficient strain of G. sulfurreducens to metabolize acetate. Evaluation of the mechanisms by which G. sulfurreducens accepts electrons from AHQDS demonstrated that a strain deficient in outer-surface c-type cytochromes that are required for AQDS reduction was as effective at QUIET as the wild-type strain. Deletion of additional genes previously implicated in extracellular electron transfer also had no impact on QUIET. These results demonstrate that QUIET can yield sufficient energy to support the growth of both syntrophic partners, but that the mechanisms by which electrons are derived from extracellular hydroquinones require

Anaerobic bacterium that degrades fatty acids in syntrophic association with methanogens

Energy Technology Data Exchange (ETDEWEB)

McInerney, M J [Univ. of Illinois, Urbana; Bryant, M P; Pfennig, N

1979-01-01

A new species of anaerobic bacterium that degrades the even-numbered carbon fatty acids, butyrate, caproate and caprylate, to acetate and H/sub 2/ and the odd-numbered carbon fatty acids, valerate and heptanoate, to acetate, propionate and H/sub 2/ was obtained in coculture with either an H/sub 2/-utilizing methanogen or H/sub 2/-utilizing desulfovibrio. The organism could be grown only in syntrophic association with the H/sub 2/-utilizer and no other energy sources or combination of electron donor and acceptors were utilized. It was a Gram-negative helical rod with 2 to 8 flagella, about 20 nm in diameter, inserted in a linear fashion about 130 nm or more apart along the concave side of the cell. It grew with a generation time of 84 h in co-culture with Methanospirillum hungatii and was present in numbers of at least 4.5 x 10/sup -6/ per g of anaerobic digest or sludge.

Evolution from a respiratory ancestor to fill syntrophic and fermentative niches: comparative fenomics of six Geobacteraceae species

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Lovley Derek R

2009-03-01

Full Text Available Abstract Background The anaerobic degradation of organic matter in natural environments, and the biotechnical use of anaerobes in energy production and remediation of subsurface environments, both require the cooperative activity of a diversity of microorganisms in different metabolic niches. The Geobacteraceae family contains members with three important anaerobic metabolisms: fermentation, syntrophic degradation of fermentation intermediates, and anaerobic respiration. Results In order to learn more about the evolution of anaerobic microbial communities, the genome sequences of six Geobacteraceae species were analyzed. The results indicate that the last common Geobacteraceae ancestor contained sufficient genes for anaerobic respiration, completely oxidizing organic compounds with the reduction of external electron acceptors, features that are still retained in modern Geobacter and Desulfuromonas species. Evolution of specialization for fermentative growth arose twice, via distinct lateral gene transfer events, in Pelobacter carbinolicus and Pelobacter propionicus. Furthermore, P. carbinolicus gained hydrogenase genes and genes for ferredoxin reduction that appear to permit syntrophic growth via hydrogen production. The gain of new physiological capabilities in the Pelobacter species were accompanied by the loss of several key genes necessary for the complete oxidation of organic compounds and the genes for the c-type cytochromes required for extracellular electron transfer. Conclusion The results suggest that Pelobacter species evolved parallel strategies to enhance their ability to compete in environments in which electron acceptors for anaerobic respiration were limiting. More generally, these results demonstrate how relatively few gene changes can dramatically transform metabolic capabilities and expand the range of environments in which microorganisms can compete.

Quantifying the percentage of methane formation via acetoclastic and syntrophic acetate oxidation pathways in anaerobic digesters.

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Jiang, Ying; Banks, Charles; Zhang, Yue; Heaven, Sonia; Longhurst, Philip

2018-01-01

Ammonia concentration is one of the key factors influencing the methanogenic community composition and dominant methanogenic pathway in anaerobic digesters. This study adopted a radiolabelling technique using [2- 14 C] acetate to investigate the relationship between total ammonia nitrogen (TAN) and the methanogenic pathway. The radiolabelling experiments determined the ratio of 14 CO 2 and 14 CH 4 in the biogas which was used to quantitatively determine the percentage of CH 4 derived from acetoclastic and syntrophic acetate oxidation routes, respectively. This technique was performed on a selection of mesophilic digesters representing samples of low to high TAN concentrations (0.2-11.1gkg -1 wet weight). In high TAN digesters, the ratio between 14 CO 2 and 14 CH 4 was in the range 2.1-3.0; indicating 68-75% of methane was produced via the hydrogenotrophic route; whereas in low ammonia samples the ratio was 0.1-0.3, indicating 9-23% of methane was produced by the hydrogenotrophic route. These findings have been confirmed further by phylogenetic studies. Copyright © 2017. Published by Elsevier Ltd.

Syntrophorhabdus aromaticivorans gen. nov., sp. nov., the first cultured anaerobe capable of degrading phenol to acetate in obligate syntrophic associations with a hydrogenotrophic methanogen.

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Qiu, Yan-Ling; Hanada, Satoshi; Ohashi, Akiyoshi; Harada, Hideki; Kamagata, Yoichi; Sekiguchi, Yuji

2008-04-01

Phenol degradation under methanogenic conditions has long been studied, but the anaerobes responsible for the degradation reaction are still largely unknown. An anaerobe, designated strain UI(T), was isolated in a pure syntrophic culture. This isolate is the first tangible, obligately anaerobic, syntrophic substrate-degrading organism capable of oxidizing phenol in association with an H(2)-scavenging methanogen partner. Besides phenol, it could metabolize p-cresol, 4-hydroxybenzoate, isophthalate, and benzoate. During the degradation of phenol, a small amount of 4-hydroxybenzoate (a maximum of 4 microM) and benzoate (a maximum of 11 microM) were formed as transient intermediates. When 4-hydroxybenzoate was used as the substrate, phenol (maximum, 20 microM) and benzoate (maximum, 92 microM) were detected as intermediates, which were then further degraded to acetate and methane by the coculture. No substrates were found to support the fermentative growth of strain UI(T) in pure culture, although 88 different substrates were tested for growth. 16S rRNA gene sequence analysis indicated that strain UI(T) belongs to an uncultured clone cluster (group TA) at the family (or order) level in the class Deltaproteobacteria. Syntrophorhabdus aromaticivorans gen. nov., sp. nov., is proposed for strain UI(T), and the novel family Syntrophorhabdaceae fam. nov. is described. Peripheral 16S rRNA gene sequences in the databases indicated that the proposed new family Syntrophorhabdaceae is largely represented by abundant bacteria within anaerobic ecosystems mainly decomposing aromatic compounds.

Syntrophic interactions improve power production in formic acid fed MFCs operated with set anode potentials or fixed resistances

KAUST Repository

Sun, Dan

2011-10-24

Formic acid is a highly energetic electron donor but it has previously resulted in low power densities in microbial fuel cells (MFCs). Three different set anode potentials (-0.30, -0.15, and +0.15V; vs. a standard hydrogen electrode, SHE) were used to evaluate syntrophic interactions in bacterial communities for formic acid degradation relative to a non-controlled, high resistance system (1,000Ω external resistance). No current was generated at -0.30V, suggesting a lack of direct formic acid oxidation (standard reduction potential: -0.40V). More positive potentials that allowed for acetic acid utilization all produced current, with the best performance at -0.15V. The anode community in the -0.15V reactor, based on 16S rDNA clone libraries, was 58% Geobacter sulfurreducens and 17% Acetobacterium, with lower proportions of these genera found in the other two MFCs. Acetic acid was detected in all MFCs suggesting that current generation by G. sulfurreducens was dependent on acetic acid production by Acetobacterium. When all MFCs were subsequently operated at an external resistance for maximum power production (100Ω for MFCs originally set at -0.15 and +0.15V; 150Ω for the control), they produced similar power densities and exhibited the same midpoint potential of -0.15V in first derivative cyclic voltammetry scans. All of the mixed communities converged to similar proportions of the two predominant genera (ca. 52% G. sulfurreducens and 22% Acetobacterium). These results show that syntrophic interactions can be enhanced through setting certain anode potentials, and that long-term performance produces stable and convergent communities. © 2011 Wiley Periodicals, Inc.

Syntrophic interactions improve power production in formic acid fed MFCs operated with set anode potentials or fixed resistances

KAUST Repository

Sun, Dan; Call, Douglas F.; Kiely, Patrick D.; Wang, Aijie; Logan, Bruce E.

2011-01-01

Formic acid is a highly energetic electron donor but it has previously resulted in low power densities in microbial fuel cells (MFCs). Three different set anode potentials (-0.30, -0.15, and +0.15V; vs. a standard hydrogen electrode, SHE) were used to evaluate syntrophic interactions in bacterial communities for formic acid degradation relative to a non-controlled, high resistance system (1,000Ω external resistance). No current was generated at -0.30V, suggesting a lack of direct formic acid oxidation (standard reduction potential: -0.40V). More positive potentials that allowed for acetic acid utilization all produced current, with the best performance at -0.15V. The anode community in the -0.15V reactor, based on 16S rDNA clone libraries, was 58% Geobacter sulfurreducens and 17% Acetobacterium, with lower proportions of these genera found in the other two MFCs. Acetic acid was detected in all MFCs suggesting that current generation by G. sulfurreducens was dependent on acetic acid production by Acetobacterium. When all MFCs were subsequently operated at an external resistance for maximum power production (100Ω for MFCs originally set at -0.15 and +0.15V; 150Ω for the control), they produced similar power densities and exhibited the same midpoint potential of -0.15V in first derivative cyclic voltammetry scans. All of the mixed communities converged to similar proportions of the two predominant genera (ca. 52% G. sulfurreducens and 22% Acetobacterium). These results show that syntrophic interactions can be enhanced through setting certain anode potentials, and that long-term performance produces stable and convergent communities. © 2011 Wiley Periodicals, Inc.

Metagenomic analyses reveal the involvement of syntrophic consortia in methanol/electricity conversion in microbial fuel cells.

Science.gov (United States)

Yamamuro, Ayaka; Kouzuma, Atsushi; Abe, Takashi; Watanabe, Kazuya

2014-01-01

Methanol is widely used in industrial processes, and as such, is discharged in large quantities in wastewater. Microbial fuel cells (MFCs) have the potential to recover electric energy from organic pollutants in wastewater; however, the use of MFCs to generate electricity from methanol has not been reported. In the present study, we developed single-chamber MFCs that generated electricity from methanol at the maximum power density of 220 mW m(-2) (based on the projected area of the anode). In order to reveal how microbes generate electricity from methanol, pyrosequencing of 16S rRNA-gene amplicons and Illumina shotgun sequencing of metagenome were conducted. The pyrosequencing detected in abundance Dysgonomonas, Sporomusa, and Desulfovibrio in the electrolyte and anode and cathode biofilms, while Geobacter was detected only in the anode biofilm. Based on known physiological properties of these bacteria, it is considered that Sporomusa converts methanol into acetate, which is then utilized by Geobacter to generate electricity. This speculation is supported by results of shotgun metagenomics of the anode-biofilm microbes, which reconstructed relevant catabolic pathways in these bacteria. These results suggest that methanol is anaerobically catabolized by syntrophic bacterial consortia with electrodes as electron acceptors.

Identification of syntrophic acetate-oxidizing bacteria in anaerobic digesters by combined protein-based stable isotope probing and metagenomics.

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Mosbæk, Freya; Kjeldal, Henrik; Mulat, Daniel G; Albertsen, Mads; Ward, Alastair J; Feilberg, Anders; Nielsen, Jeppe L

2016-10-01

Inhibition of anaerobic digestion through accumulation of volatile fatty acids occasionally occurs as the result of unbalanced growth between acidogenic bacteria and methanogens. A fast recovery is a prerequisite for establishing an economical production of biogas. However, very little is known about the microorganisms facilitating this recovery. In this study, we investigated the organisms involved by a novel approach of mapping protein-stable isotope probing (protein-SIP) onto a binned metagenome. Under simulation of acetate accumulation conditions, formations of (13)C-labeled CO2 and CH4 were detected immediately following incubation with [U-(13)C]acetate, indicating high turnover rate of acetate. The identified (13)C-labeled peptides were mapped onto a binned metagenome for improved identification of the organisms involved. The results revealed that Methanosarcina and Methanoculleus were actively involved in acetate turnover, as were five subspecies of Clostridia. The acetate-consuming organisms affiliating with Clostridia all contained the FTFHS gene for formyltetrahydrofolate synthetase, a key enzyme for reductive acetogenesis, indicating that these organisms are possible syntrophic acetate-oxidizing (SAO) bacteria that can facilitate acetate consumption via SAO, coupled with hydrogenotrophic methanogenesis (SAO-HM). This study represents the first study applying protein-SIP for analysis of complex biogas samples, a promising method for identifying key microorganisms utilizing specific pathways.

Identification of syntrophic acetate-oxidizing bacteria in anaerobic digesters by combined protein-based stable isotope probing and metagenomics

Science.gov (United States)

Mosbæk, Freya; Kjeldal, Henrik; Mulat, Daniel G; Albertsen, Mads; Ward, Alastair J; Feilberg, Anders; Nielsen, Jeppe L

2016-01-01

Inhibition of anaerobic digestion through accumulation of volatile fatty acids occasionally occurs as the result of unbalanced growth between acidogenic bacteria and methanogens. A fast recovery is a prerequisite for establishing an economical production of biogas. However, very little is known about the microorganisms facilitating this recovery. In this study, we investigated the organisms involved by a novel approach of mapping protein-stable isotope probing (protein-SIP) onto a binned metagenome. Under simulation of acetate accumulation conditions, formations of 13C-labeled CO2 and CH4 were detected immediately following incubation with [U-13C]acetate, indicating high turnover rate of acetate. The identified 13C-labeled peptides were mapped onto a binned metagenome for improved identification of the organisms involved. The results revealed that Methanosarcina and Methanoculleus were actively involved in acetate turnover, as were five subspecies of Clostridia. The acetate-consuming organisms affiliating with Clostridia all contained the FTFHS gene for formyltetrahydrofolate synthetase, a key enzyme for reductive acetogenesis, indicating that these organisms are possible syntrophic acetate-oxidizing (SAO) bacteria that can facilitate acetate consumption via SAO, coupled with hydrogenotrophic methanogenesis (SAO-HM). This study represents the first study applying protein-SIP for analysis of complex biogas samples, a promising method for identifying key microorganisms utilizing specific pathways. PMID:27128991

Metagenomic analyses reveal the involvement of syntrophic consortia in methanol/electricity conversion in microbial fuel cells.

Directory of Open Access Journals (Sweden)

Ayaka Yamamuro

Full Text Available Methanol is widely used in industrial processes, and as such, is discharged in large quantities in wastewater. Microbial fuel cells (MFCs have the potential to recover electric energy from organic pollutants in wastewater; however, the use of MFCs to generate electricity from methanol has not been reported. In the present study, we developed single-chamber MFCs that generated electricity from methanol at the maximum power density of 220 mW m(-2 (based on the projected area of the anode. In order to reveal how microbes generate electricity from methanol, pyrosequencing of 16S rRNA-gene amplicons and Illumina shotgun sequencing of metagenome were conducted. The pyrosequencing detected in abundance Dysgonomonas, Sporomusa, and Desulfovibrio in the electrolyte and anode and cathode biofilms, while Geobacter was detected only in the anode biofilm. Based on known physiological properties of these bacteria, it is considered that Sporomusa converts methanol into acetate, which is then utilized by Geobacter to generate electricity. This speculation is supported by results of shotgun metagenomics of the anode-biofilm microbes, which reconstructed relevant catabolic pathways in these bacteria. These results suggest that methanol is anaerobically catabolized by syntrophic bacterial consortia with electrodes as electron acceptors.

Interspecies acetate transfer influences the extent of anaerobic benzoate degradation by syntrophic consortia

Energy Technology Data Exchange (ETDEWEB)

Warikoo, V.; McInerney, M.J.; Suflita, J.M. [and others

1997-03-01

Benzoate degradation by an anaerobic, syntrophic bacterium, strain SB, in coculture with Desulfovibrio strain G-11 reached a threshold value which depended on the amount of acetate added, and ranged from about 2.5 to 29.9 {mu}M. Increasing acetate concentrations also uncompetitively inhibited benzoate degradation. The apparent V{sub max} and K{sub m} for benzoate degradation decreased with increasing acetate concentration, but the benzoate degradation capacity (V{sub max}/K{sub m}) of cell suspensions remained comparable. The addition of an acetate-using bacterium to cocultures after the threshold was reached resulted in the degradation of benzoate to below the detection limit. Mathematical simulations showed that the benzoate threshold was not predicted by the inhibitory effect of acetate on benzoate degradation kinetics. With nitrate instead of sulfate as the terminal electron acceptor, no benzoate threshold was observed in the presence of 20 mM acetate even though the degradation capacity was lower with nitrate than with sulfate. When strain SB was grown with a hydrogen-using partner that had a 5-fold lower hydrogen utilization capacity, a 5 to 9-fold lower the benzoate degradation capacity was observed compared to SB/G-11 cocultures. The Gibb`s free energy for benzoate degradation was less negative in cell suspensions with threshold compared to those without threshold. These studies showed that the threshold was not a function of the inhibition of benzoate degradation capacity by acetate, or the toxicity of the undissociated form of acetate. Rather a critical or minimal Gibb`s free energy may exist where thermodynamic constraints preclude further benzoate degradation.

Syntrophic co-culture of aerobic Bacillus and anaerobic Clostridium for bio-fuels and bio-hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Chang, Jui-Jen; Ho, Cheng-Yu.; Chen, Wei-En; Huang, Chieh-Chen [Department of Life Sciences, National Chung Hsing University, Taichung (China); Chou, Chia-Hung; Lay, Jiunn-Jyi [Department of Science and Technology, National Kaohsiung First University, Kaohsiung (China)

2008-10-15

By using brewery yeast waste and microflora from rice straw compost, an anaerobic semi-solid bio-hydrogen-producing system has been established. For the purpose of industrialization, the major players of both aerobic and anaerobic bacterial strains in the system were isolated and their combination for an effective production of bio-hydrogen and other bio-fuels was examined in this study. The phylogenetic analysis found that four anaerobic isolates (Clostridium beijerinckii L9, Clostridium diolis Z2, Clostridium roseum Z5-1, and C. roseum W8) were highly related with each other and belongs to the cluster I clostridia family, the family that many of solvent-producing strains included. On the other hand, one of the aerobic isolates, the Bacillus thermoamylovorans strain I, shown multiple extracellular enzyme activities including lipase, protease, {alpha}-amylase, pectinase and cellulase, was suggested as a good partner for creating an anaerobic environment and pre-saccharification of substrate for those co-cultured solventogenic clostridial strain. Among these clostridial strains, though C. beijerinckii L9 do not show as many extracellular enzyme activities as Bacillus, but it performs the highest hydrogen-producing ability. The original microflora can be updated to a syntrophic bacterial co-culture system contended only with B. thermoamylovorans I and C. beijerinckii L9. The combination of aerobic Bacillus and anaerobic Clostridium may play the key role for developing the industrialized bio-fuels and bio-hydrogen-producing system from biomass. (author)

Link Between Capacity for Current Production and Syntrophic Growth in Geobacter species

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Amelia-Elena eRotaru

2015-07-01

Full Text Available Electrodes are unnatural electron acceptors, and it is yet unknown how some Geobacter species evolved to use electrodes as terminal electron acceptors. Analysis of different Geobacter species revealed that they varied in their capacity for current production. G. metallireducens and G. hydrogenophilus generated high current densities (ca. 0.05 mA/cm2, comparable to G. sulfurreducens. G. bremensis, G. chapellei, G. humireducens, and G. uranireducens, produced much lower currents (ca. 0.05 mA/cm2 and G. bemidjiensis was previously found to not produce current. There was no correspondence between the effectiveness of current generation and Fe(III oxide reduction rates. Some high-current-density strains (G. metallireducens and G. hydrogenophilus reduced Fe(III-oxides as fast as some low-current-density strains (G. bremensis, G. humireducens, and G. uranireducens whereas other low-current-density strains (G. bemidjiensis and G. chapellei reduced Fe(III oxide as slowly as G. sulfurreducens, a high-current-density strain. However, there was a correspondence between the ability to produce higher currents and the ability to grow syntrophically. G. hydrogenophilius was found to grow in co-culture with Methanosarcina barkeri, which is capable of direct interspecies electron transfer (DIET, but not with Methanospirillium hungatei capable only of H2 or formate transfer. Conductive granular activated carbon (GAC stimulated metabolism of the G. hydrogenophilus - M. barkeri co-culture, consistent with electron exchange via DIET. These findings, coupled with the previous finding that G. metallireducens and G. sulfurreducens are also capable of DIET, suggest that evolution to optimize DIET has fortuitiously conferred the capability for high-density current production to some Geobacter species.

Syntrophic microbial communities on straw as biofilm carrier increase the methane yield of a biowaste-digesting biogas reactor

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Frank R. Bengelsdorf

2015-08-01

Full Text Available Biogas from biowaste can be an important source of renewable energy, but the fermentation process of low-structure waste is often unstable. The present study uses a full-scale biogas reactor to test the hypothesis that straw as an additional biofilm carrier will increase methane yield; and this effect is mirrored in a specific microbial community attached to the straw. Better reactor performance after addition of straw, at simultaneously higher organic loading rate and specific methane yield confirmed the hypothesis. The microbial communities on straw as a biofilm carrier and of the liquid reactor content were investigated using 16S rDNA amplicon sequencing by means of 454 pyrosequencing technology. The results revealed high diversity of the bacterial communities in the liquid reactor content as well as the biofilms on the straw. The most abundant archaea in all samples belonged to the genera Methanoculleus and Methanosarcina. Addition of straw resulted in a significantly different microbial community attached to the biofilm carrier. The bacterium Candidatus Cloacamonas acidaminovorans and methanogenic archaea of the genus Methanoculleus dominated the biofilm on straw. Syntrophic interactions between the hydrogenotrophic Methanoculleus sp. and members of the hydrogen-producing bacterial community within biofilms may explain the improved methane yield. Thus, straw addition can be used to improve and to stabilize the anaerobic process in substrates lacking biofilm-supporting structures.

In silico approaches to study mass and energy flows in microbial consortia: a syntrophic case study

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Mallette Natasha

2009-12-01

Full Text Available Abstract Background Three methods were developed for the application of stoichiometry-based network analysis approaches including elementary mode analysis to the study of mass and energy flows in microbial communities. Each has distinct advantages and disadvantages suitable for analyzing systems with different degrees of complexity and a priori knowledge. These approaches were tested and compared using data from the thermophilic, phototrophic mat communities from Octopus and Mushroom Springs in Yellowstone National Park (USA. The models were based on three distinct microbial guilds: oxygenic phototrophs, filamentous anoxygenic phototrophs, and sulfate-reducing bacteria. Two phases, day and night, were modeled to account for differences in the sources of mass and energy and the routes available for their exchange. Results The in silico models were used to explore fundamental questions in ecology including the prediction of and explanation for measured relative abundances of primary producers in the mat, theoretical tradeoffs between overall productivity and the generation of toxic by-products, and the relative robustness of various guild interactions. Conclusion The three modeling approaches represent a flexible toolbox for creating cellular metabolic networks to study microbial communities on scales ranging from cells to ecosystems. A comparison of the three methods highlights considerations for selecting the one most appropriate for a given microbial system. For instance, communities represented only by metagenomic data can be modeled using the pooled method which analyzes a community's total metabolic potential without attempting to partition enzymes to different organisms. Systems with extensive a priori information on microbial guilds can be represented using the compartmentalized technique, employing distinct control volumes to separate guild-appropriate enzymes and metabolites. If the complexity of a compartmentalized network creates an

Biostimulation induces syntrophic interactions that impact C, S and N cycling in a sediment microbial community

Energy Technology Data Exchange (ETDEWEB)

Handley, KM [University of California, Berkeley; Verberkmoes, Nathan C [ORNL; Steefel, Carl I [Lawrence Berkeley National Laboratory (LBNL); Sharon, I [University of California, Berkeley; Williams, Ken [Lawrence Berkeley National Laboratory (LBNL); Miller, CS [University of California, Berkeley; Frischkorn, Kyle C [University of California, Berkeley; Chourey, Karuna [ORNL; Thomas, Brian [University of California, Berkeley; Shah, Manesh B [ORNL; Long, Phil [Pacific Northwest National Laboratory (PNNL); Hettich, Robert {Bob} L [ORNL; Banfield, Jillian F. [University of California, Berkeley

2013-01-01

Stimulation of subsurface microorganisms to induce reductive immobilization of metals is a promising approach for bioremediation, yet the overall microbial community response is typically poorly understood. Here we used community proteogenomics to test the hypothesis that excess input of acetate activates syntrophic interactions among autotrophs and heterotrophs. A flow-through sediment column was incubated in a groundwater well of an acetate-amended aquifer. Genomic sequences from the community recovered during microbial sulfate reduction were used to econstruct, de novo, near-complete genomes for Desulfobacter (Deltaproteobacteria) and relatives of Sulfurovum and Sulfurimonas (Epsilonproteobacteria), and Bacteroidetes. Partial genomes were obtained for Clostridiales (Firmicutes) and Desulfuromonadales-like Deltaproteobacteria. The majority of proteins identified by mass spectrometry corresponded to Desulfobacter-like species, and demonstrate the role of this organism in sulfate reduction (Dsr and APS), nitrogen-fixation (Nif) and acetate oxidation to CO2 during amendment. Results suggest less abundant Desulfuromonadales and Bacteroidetes also actively contributed to CO2 production via the TCA cycle. Proteomic data indicate that sulfide was partially re-oxidized by Epsilonproteobacteria through nitrate-dependent sulfide oxidation (using Nap, Nir, Nos, SQR and Sox), with CO2 fixed using the reverse TCA cycle. Modeling shows that this reaction was thermodynamically possible, and kinetically favorable relative to acetate-dependent denitrification. We conclude that high-levels of carbon amendment aimed to stimulate anaerobic heterotrophy led to carbon fixation in co-dependent chemoautotrophs. These results have implications for understanding complex ecosystem behavior, and show that high levels of organic carbon supplementation can expand the range of microbial functionalities accessible for ecosystem manipulation.

Dynamic changes of carbon isotope apparent fractionation factor to describe transition to syntrophic acetate oxidation during cellulose and acetate methanization.

Science.gov (United States)

Vavilin, Vasily A; Rytov, Sergey V

2017-05-01

To identify predominant metabolic pathway for cellulose methanization new equations that take into account dynamics of 13C are added to the basic model of cellulose methanization. The correct stoichiometry of hydrolysis, acidogenesis, acetogenesis and methanogenesis steps including biomass is considered. Using experimental data by Laukenmann et al. [Identification of methanogenic pathway in anaerobic digesters using stable carbon isotopes. Eng. Life Sci. 2010;10:1-6], who reported about the importance of ace`tate oxidation during mesophilic cellulose methanization, the model confirmed that, at high biomass concentration of acetate oxidizers, the carbon isotope fractionation factor amounts to about 1.085. The same model, suggested firstly for cellulose degradation, was used to describe, secondly, changes in, and in methane and carbon dioxide during mesophylic acetate methanization measured by Grossin-Debattista [Fractionnements isotopiques (13C/12C) engendres par la methanogenese: apports pour la comprehension des processus de biodegradation lors de la digestion anaerobie [doctoral thesis]. 2011. Bordeaux: Universite Bordeaux-1;2011. Available from: http://ori-oai.u-bordeaux1.fr/pdf/2011/GROSSIN-DEBATTISTA_JULIEN_2011.pdf . French].The model showed that under various ammonium concentrations, at dominating acetoclastic methanogenesis, the value decreases over time to a low level (1.016), while at dominating syntrophic acetate oxidation, coupled with hydrogenotrophic methanogenesis, slightly increases, reaching 1.060 at the end of incubation.

Methanogenic paraffin degradation proceeds via alkane addition to fumarate by 'Smithella' spp. mediated by a syntrophic coupling with hydrogenotrophic methanogens.

Science.gov (United States)

Wawrik, Boris; Marks, Christopher R; Davidova, Irene A; McInerney, Michael J; Pruitt, Shane; Duncan, Kathleen E; Suflita, Joseph M; Callaghan, Amy V

2016-09-01

Anaerobic microbial biodegradation of recalcitrant, water-insoluble substrates, such as paraffins, presents unique metabolic challenges. To elucidate this process, a methanogenic consortium capable of mineralizing long-chain n-paraffins (C28 -C50 ) was enriched from San Diego Bay sediment. Analysis of 16S rRNA genes indicated the dominance of Syntrophobacterales (43%) and Methanomicrobiales (26%). Metagenomic sequencing allowed draft genome assembly of dominant uncultivated community members belonging to the bacterial genus Smithella and the archaeal genera Methanoculleus and Methanosaeta. Five contigs encoding homologs of the catalytic subunit of alkylsuccinate synthase (assA) were detected. Additionally, mRNA transcripts for these genes, including a homolog binned within the 'Smithella' sp. SDB genome scaffold, were detected via RT-PCR, implying that paraffins are activated via 'fumarate addition'. Metabolic reconstruction and comparison with genome scaffolds of uncultivated n-alkane degrading 'Smithella' spp. are consistent with the hypothesis that syntrophically growing 'Smithella' spp. may achieve reverse electron transfer by coupling the reoxidation of ETFred to a membrane-bound FeS oxidoreductase functioning as an ETF:menaquinone oxidoreductase. Subsequent electron transfer could proceed via a periplasmic formate dehydrogenase and/or hydrogenase, allowing energetic coupling to hydrogenotrophic methanogens such as Methanoculleus. Ultimately, these data provide fundamental insight into the energy conservation mechanisms that dictate interspecies interactions salient to methanogenic alkane mineralization. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

Hydrogen limitation and syntrophic growth among natural assemblages of thermophilic methanogens at deep-sea hydrothermal vents

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Begüm D. Topçuoğlu

2016-08-01

Full Text Available Thermophilic methanogens are common autotrophs at hydrothermal vents, but their growth constraints and dependence on H2 syntrophy in situ are poorly understood. Between 2012 and 2015, methanogens and H2-producing heterotrophs were detected by growth at 80°C and 55°C at most diffuse (7-40°C hydrothermal vent sites at Axial Seamount. Microcosm incubations of diffuse hydrothermal fluids at 80°C and 55°C demonstrated that growth of thermophilic and hyperthermophilic methanogens is primarily limited by H2 availability. Amendment of microcosms with NH4+ generally had no effect on CH4 production. However, annual variations in abundance and CH4 production were observed in relation to the eruption cycle of the seamount. Microcosm incubations of hydrothermal fluids at 80°C and 55°C supplemented with tryptone and no added H2 showed CH4 production indicating the capacity in situ for methanogenic H2 syntrophy. 16S rRNA genes were found in 80°C microcosms from H2-producing archaea and H2-consuming methanogens, but not for any bacteria. In 55°C microcosms, sequences were found from the H2-producing bacteria and H2-consuming methanogens and sulfate-reducing bacteria. A co-culture of representative organisms showed that Thermococcus paralvinellae supported the syntrophic growth of Methanocaldococcus bathoardescens at 82°C and Methanothermococcus sp. strain BW11 at 60°C. The results demonstrate that modeling of subseafloor methanogenesis should focus primarily on H2 availability and temperature, and that thermophilic H2 syntrophy can support methanogenesis within natural microbial assemblages and may be an important energy source for thermophilic autotrophs in marine geothermal environments.

More than 2500 years of oil exposure shape sediment microbiomes with the potential for syntrophic degradation of hydrocarbons linked to methanogenesis.

Science.gov (United States)

Michas, Antonios; Vestergaard, Gisle; Trautwein, Kathleen; Avramidis, Pavlos; Hatzinikolaou, Dimitris G; Vorgias, Constantinos E; Wilkes, Heinz; Rabus, Ralf; Schloter, Michael; Schöler, Anne

2017-09-11

Natural oil seeps offer the opportunity to study the adaptation of ecosystems and the associated microbiota to long-term oil exposure. In the current study, we investigated a land-to-sea transition ecosystem called "Keri Lake" in Zakynthos Island, Greece. This ecosystem is unique due to asphalt oil springs found at several sites, a phenomenon already reported 2500 years ago. Sediment microbiomes at Keri Lake were studied, and their structure and functional potential were compared to other ecosystems with oil exposure histories of various time periods. Replicate sediment cores (up to 3-m depth) were retrieved from one site exposed to oil as well as a non-exposed control site. Samples from three different depths were subjected to chemical analysis and metagenomic shotgun sequencing. At the oil-exposed site, we observed high amounts of asphalt oil compounds and a depletion of sulfate compared to the non-exposed control site. The numbers of reads assigned to genes involved in the anaerobic degradation of hydrocarbons were similar between the two sites. The numbers of denitrifiers and sulfate reducers were clearly lower in the samples from the oil-exposed site, while a higher abundance of methanogens was detected compared to the non-exposed site. Higher abundances of the genes of methanogenesis were also observed in the metagenomes from other ecosystems with a long history of oil exposure, compared to short-term exposed environments. The analysis of Keri Lake metagenomes revealed that microbiomes in the oil-exposed sediment have a higher potential for methanogenesis over denitrification/sulfate reduction, compared to those in the non-exposed site. Comparison with metagenomes from various oil-impacted environments suggests that syntrophic interactions of hydrocarbon degraders with methanogens are favored in the ecosystems with a long-term presence of oil.

Case Study: Testing with Case Studies

Science.gov (United States)

Herreid, Clyde Freeman

2015-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

CASE STUDY CRITIQUE; UPPER CLINCH CASE STUDY

Science.gov (United States)

Case study critique: Upper Clinch case study (from Research on Methods for Integrating Ecological Economics and Ecological Risk Assessment: A Trade-off Weighted Index Approach to Integrating Economics and Ecological Risk Assessment). This critique answers the questions: 1) does ...

Sustainable syntrophic growth of Dehalococcoides ethenogenes strain 195 with Desulfovibrio vulgaris Hildenborough and Methanobacterium congolense: Global transcriptomic and proteomic analyses

Energy Technology Data Exchange (ETDEWEB)

Men, Y.; Feil, H.; VerBerkmoes, N.C.; Shah, M.B.; Johnson, D.R.; Lee, P.K.H; West, K.A.; Zinder, S.H.; Andersen, G.L.; Alvarez-Cohen, L.

2011-03-01

Dehalococcoides ethenogenes strain 195 (DE195) was grown in a sustainable syntrophic association with Desulfovibrio vulgaris Hildenborough (DVH) as a co-culture, as well as with DVH and the hydrogenotrophic methanogen Methanobacterium congolense (MC) as a tri-culture using lactate as the sole energy and carbon source. In the co- and tri-cultures, maximum dechlorination rates of DE195 were enhanced by approximately three times (11.0±0.01 lmol per day for the co-culture and 10.1±0.3 lmol per day for the tri-culture) compared with DE195 grown alone (3.8±0.1 lmol per day). Cell yield of DE195 was enhanced in the co-culture (9.0±0.5 x 107 cells per lmol Cl{sup -} released, compared with 6.8±0.9x 107 cells per lmol Cl{sup -} released for the pure culture), whereas no further enhancement was observed in the tri-culture (7.3±1.8x 107 cells per lmol Cl{sup -} released). The transcriptome of DE195 grown in the co-culture was analyzed using a whole-genome microarray targeting DE195, which detected 102 significantly up- or down-regulated genes compared with DE195 grown in isolation, whereas no significant transcriptomic difference was observed between co- and tri-cultures. Proteomic analysis showed that 120 proteins were differentially expressed in the co-culture compared with DE195 grown in isolation. Physiological, transcriptomic and proteomic results indicate that the robust growth of DE195 in co- and tri-cultures is because of the advantages associated with the capabilities of DVH to ferment lactate to provide H2 and acetate for growth, along with potential benefits from proton translocation, cobalamin-salvaging and amino acid biosynthesis, whereas MC in the tri-culture provided no significant additional benefits beyond those of DVH.

Subgroup characteristics of marine methane-oxidizing ANME-2 archaea and their syntrophic partners revealed by integrated multimodal analytical microscopy.

Science.gov (United States)

McGlynn, Shawn E; Chadwick, Grayson L; O'Neill, Ariel; Mackey, Mason; Thor, Andrea; Deerinck, Thomas J; Ellisman, Mark H; Orphan, Victoria J

2018-04-06

Phylogenetically diverse environmental ANME archaea and sulfate-reducing bacteria cooperatively catalyze the anaerobic oxidation of methane oxidation (AOM) in multi-celled consortia within methane seep environments. To better understand these cells and their symbiotic associations, we applied a suite of electron microscopy approaches including correlative f luorescence i n s itu h ybridization - e lectron m icroscopy (FISH-EM), t ransmission e lectron m icroscopy (TEM), and s erial b lock face scanning e lectron m icroscopy 3D reconstructions (SBEM). FISH-EM of methane seep derived consortia revealed phylogenetic variability in terms of cell morphology, ultrastructure, and storage granules. Representatives of the ANME-2b clade, but not other ANME-2 groups, contained polyphosphate-like granules, while some bacteria associated with ANME-2a/2c contained two distinct phases of iron mineral chains resembling magnetosomes. 3D segmentation of two ANME-2 consortia types revealed cellular volumes of ANME and their symbiotic partners which were larger than previous estimates based on light microscopy. Phosphorous granule containing ANME (tentatively ANME-2b) were larger than both ANME with no granules and partner bacteria. This cell type was observed with up to 4 granules per cell and the volume of the cell was larger in proportion to the number of granules inside it, but the percent of the cell occupied by these granules did not vary with granule number. These results illuminate distinctions between ANME-2 archaeal lineages and partnering bacterial populations that are apparently unified in their capability of performing anaerobic methane oxidation. Importance Methane oxidation in anaerobic environments can be accomplished by a number of archaeal groups, some of which live in syntrophic relationships with bacteria in structured consortia. Little is known as to the distinguishing characteristics of these groups. Here we applied imaging approaches to better understand the

Case Study Research Methodology

Directory of Open Access Journals (Sweden)

Mark Widdowson

2011-01-01

Full Text Available Commenting on the lack of case studies published in modern psychotherapy publications, the author reviews the strengths of case study methodology and responds to common criticisms, before providing a summary of types of case studies including clinical, experimental and naturalistic. Suggestions are included for developing systematic case studies and brief descriptions are given of a range of research resources relating to outcome and process measures. Examples of a pragmatic case study design and a hermeneutic single-case efficacy design are given and the paper concludes with some ethical considerations and an exhortation to the TA community to engage more widely in case study research.

Project management case studies

CERN Document Server

Kerzner, Harold R

2013-01-01

A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

Anaerobic biodegradation of cellulosic material: Batch experiments and modelling based on isotopic data and focusing on aceticlastic and non-aceticlastic methanogenesis

International Nuclear Information System (INIS)

Qu, X.; Vavilin, V.A.; Mazeas, L.; Lemunier, M.; Duquennoi, C.; He, P.-J.; Bouchez, T.

2009-01-01

Utilizing stable carbon isotope data to account for aceticlastic and non-aceticlastic pathways of methane generation, a model was created to describe laboratory batch anaerobic decomposition of cellulosic materials (office paper and cardboard). The total organic and inorganic carbon concentrations, methane production volume, and methane and CO 2 partial pressure values were used for the model calibration and validation. According to the fluorescent in situ hybridization observations, three groups of methanogens including strictly hydrogenotrophic methanogens, strictly aceticlastic methanogens (Methanosaeta sp.) and Methanosarcina sp., consuming both acetate and H 2 /H 2 CO 3 as well as acetate-oxidizing syntrophs, were considered. It was shown that temporary inhibition of aceticlastic methanogens by non-ionized volatile fatty acids or acidic pH was responsible for two-step methane production from office paper at 35 o C where during the first and second steps methane was generated mostly from H 2 /H 2 CO 3 and acetate, respectively. Water saturated and unsaturated cases were tested. According to the model, at the intermediate moisture (150%), much lower methane production occurred because of full-time inhibition of aceticlastic methanogens. At the lowest moisture, methane production was very low because most likely hydrolysis was seriously inhibited. Simulations showed that during cardboard and office paper biodegradation at 55 o C, non-aceticlastic syntrophic oxidation by acetate-oxidizing syntrophs and hydrogenotrophic methanogens were the dominant methanogenic pathways.

Metabolic interactions in methanogenic and sulfate-reducing bioreactors.

Science.gov (United States)

Stams, A J M; Plugge, C M; de Bok, F A M; van Houten, B H G W; Lens, P; Dijkman, H; Weijma, J

2005-01-01

In environments where the amount of electron acceptors is insufficient for complete breakdown of organic matter, methane is formed as the major reduced end product. In such methanogenic environments organic acids are degraded by syntrophic consortia of acetogenic bacteria and methanogenic archaea. Hydrogen consumption by methanogens is essential for acetogenic bacteria to convert organic acids to acetate and hydrogen. Several syntrophic cocultures growing on propionate and butyrate have been described. These syntrophic fatty acid-degrading consortia are affected by the presence of sulfate. When sulfate is present sulfate-reducing bacteria compete with methanogenic archaea for hydrogen and acetate, and with acetogenic bacteria for propionate and butyrate. Sulfate-reducing bacteria easily outcompete methanogens for hydrogen, but the presence of acetate as carbon source may influence the outcome of the competition. By contrast, acetoclastic methanogens can compete reasonably well with acetate-degrading sulfate reducers. Sulfate-reducing bacteria grow much faster on propionate and butyrate than syntrophic consortia.

[Case and studies].

Science.gov (United States)

Schubert, András

2015-11-15

Case studies and case reports form an important and ever growing part of scientific and scholarly literature. The paper deals with the share and citation rate of these publication types on different fields of research. In general, evidence seems to support the opinion that an excessive number of such publications may negatively influence the impact factor of the journal. In the literature of scientometrics, case studies (at least the presence of the term "case study" in the titles of the papers) have a moderate share, but their citation rate is practically equal to that of other publication types.

Building theories from case study research: the progressive case study

NARCIS (Netherlands)

Steenhuis, H.J.; de Bruijn, E.J.

2006-01-01

Meredith (1998) argues for more case and field research studies in the field of operations management. Based on a literature review, we discuss several existing approaches to case studies and their characteristics. These approaches include; the Grounded Theory approach which proposes no prior

Final report on case studies

DEFF Research Database (Denmark)

Ljungberg, Daniel; McKelvey, Maureen; Lassen, Astrid Heidemann

2012-01-01

Case study as a research design means investigating a single or multiple instance(s) or setting(s) (i.e. a case) and its entire context to explain a phenomenon and its processes. This is achieved through detailed understanding, usually comprised of multiple sources of information. In this way, case...... studies attempt to provide as a complete an understanding of a (complex) phenomenon as possible. Within the AEGIS project, survey and case study research are complementary. They are complementary in the sense that the former can provide more generalizable evidence on a phenomenon in terms of cross......-sectional data, while the latter can provide more in-depth (qualitative) understanding on specific issues. In systematically examining the case studies, however, this report goes beyond a typical single case study. Here we provide a synthesis of 86 case studies. Multiple case studies, following similar focus...

[Case-non case studies: Principles, methods, bias and interpretation].

Science.gov (United States)

Faillie, Jean-Luc

2017-10-31

Case-non case studies belongs to the methods assessing drug safety by analyzing the disproportionality of notifications of adverse drug reactions in pharmacovigilance databases. Used for the first time in the 1980s, the last few decades have seen a significant increase in the use of this design. The principle of the case-non case study is to compare drug exposure in cases of a studied adverse reaction with that of cases of other reported adverse reactions and called "non cases". Results are presented in the form of a reporting odds ratio (ROR), the interpretation of which makes it possible to identify drug safety signals. This article describes the principle of the case-non case study, the method of calculating the ROR and its confidence interval, the different modalities of analysis and how to interpret its results with regard to the advantages and limitations of this design. Copyright © 2017 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.

Case-control studies in neurosurgery.

Science.gov (United States)

Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

2014-08-01

Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

Evaluation of support matrices for immobilization of anaerobic consortia for efficient carbon cycling in waste regeneration.

Science.gov (United States)

Chauhan, Ashvini; Ogram, Andrew

2005-02-18

Efficient metabolism of fatty acids during anaerobic waste digestion requires development of consortia that include "fatty acid consuming H(2) producing bacteria" and methanogenic bacteria. The objective of this research was to optimize methanogenesis from fatty acids by evaluating a variety of support matrices for use in maintaining efficient syntrophic-methanogenic consortia. Tested matrices included clays (montmorillonite and bentonite), glass beads (106 and 425-600mum), microcarriers (cytopore, cytodex, cytoline, and cultispher; conventionally employed for cultivation of mammalian cell lines), BioSep beads (powdered activated carbon), and membranes (hydrophilic; nylon, polysulfone, and hydrophobic; teflon, polypropylene). Data obtained from headspace methane (CH(4)) analyses as an indicator of anaerobic carbon cycling efficiency indicated that material surface properties were important in maintenance and functioning of the anaerobic consortia. Cytoline yielded significantly higher CH(4) than other matrices as early as in the first week of incubation. 16S rRNA gene sequence analysis from crushed cytoline matrix showed the presence of Syntrophomonas spp. (butyrate oxidizing syntrophs) and Syntrophobacter spp. (propionate oxidizing syntrophs), with Methanosaeta spp. (acetate utilizing methanogen), and Methanospirillum spp. (hydrogen utilizing methanogen) cells. It is likely that the more hydrophobic surfaces provided a suitable surface for adherence of cells of syntrophic-methanogenic consortia. Cytoline also appeared to protect entrapped consortia from air, resulting in rapid methanogenesis after aerial exposure. Our study suggests that support matrices can be used in anaerobic digestors, pre-seeded with immobilized or entrapped consortia on support matrices, and may be of value as inoculant-adsorbents to rapidly initiate or recover proper system functioning following perturbation.

Case Study: Mini-Case Studies: Small Infusions of Active Learning for Large-Lecture Courses

Science.gov (United States)

Carloye, Lisa

2017-01-01

In this article, the author introduces the usage of case studies to be an excellent method for engaging students through stories. The author notes she developed a series of mini-case studies that can be implemented, with a little advance preparation, within a 10- to 15-minute window during lecture. What makes them "mini" case studies?…

BioFleet case studies

International Nuclear Information System (INIS)

2007-01-01

These six case studies examined the use of different biodiesel blends as fuel supply sources for businesses in British Columbia (BC). In the first case study, 6 municipalities participated in a pilot program designed to compare the performance of biodiesel and diesel fuels. Each municipality operated 2 base vehicles running on conventional diesel along with 2 similar vehicles which used biodiesel. Real time emissions tests and analyses of the vehicles using biodiesel were also conducted by 2 of the participating municipalities. All municipalities participating in the study agreed to purchase significant volumes of biodiesel. The second case study described a pilot study conducted by the City of Vancouver's equipment services branch in 2004. As a result of the study, the city now has over 530 types of equipment that use biodiesel. The third case study described a program designed by TSI Terminals in Vancouver to assess the emission reduction impact of using biodiesel at its port facility. Six different pieces of equipment were used to confirm that biodiesel could be used throughout the terminal. Test results confirmed that biodiesel blends could be used to reduce emissions. Overall emissions were reduced by 30 per cent. The fourth case study described a waste renderer that used a fleet of 36 trucks to deliver raw products to its plants. The company made the decision to use only biodiesel for its entire fleet of trucks. Since July 2005, the company has logged over 1.7 million km using biodiesel blends. The fifth case study described a salmon hatchery that switched from diesel to biodiesel in order to reduce emissions. The biodiesel blends are used to fuel the hatchery's 2 diesel generators. The hatchery has reduced emissions of greenhouse gases (GHGs) by an estimated 1800 tonnes annually. The sixth case study described how the Township of Langley has started using biodiesel for its entire fleet of of approximately 250 pieces of equipment. The township has not

Thermosyntropha lipolytica gen. nov., sp. nov., a lipolytic, anaerobic, alkalitolerant, thermophilic bacterium utilizing short- and long-chain fatty acids in syntrophic coculture with a methanogenic archaeum.

Science.gov (United States)

Svetlitshnyi, V; Rainey, F; Wiegel, J

1996-10-01

Three strains of an anaerobic thermophilic organoheterotrophic lipolytic alkalitolerant bacterium, Thermosyntropha lipolytica gen. nov., sp. nov. (type strain JW/VS-265T; DSM 11003), were isolated from alkaline hot springs of Lake Bogoria (Kenya). The cells were nonmotile, non-spore forming, straight or slightly curved rods. At 60 degrees C the pH range for growth determined at 25 degrees C [pH25 degrees C] was 7.15 to 9.5, with an optimum between 8.1 and 8.9 (pH60 degrees C of 7.6 and 8.1). At a pH25 degrees C of 8.5 the temperature range for growth was from 52 to 70 degrees C, with an optimum between 60 and 66 degrees C. The shortest doubling time was around 1 h. In pure culture the bacterium grew in a mineral base medium supplemented with yeast extract, tryptone, Casamino Acids, betaine, and crotonate as carbon sources, producing acetate as a major product and constitutively a lipase. During growth in the presence of olive oil, free long-chain fatty acids were accumulated in the medium but the pure culture could not utilize olive oil, triacylglycerols, short- and long-chain fatty acids, and glycerol for growth. In syntrophic coculture (Methanobacterium strain JW/VS-M29) the lipolytic bacteria grew on triacylglycerols and linear saturated and unsaturated fatty acids with 4 to 18 carbon atoms, but glycerol was not utilized. Fatty acids with even numbers of carbon atoms were degraded to acetate and methane, while from odd-numbered fatty acids 1 mol of propionate per mol of fatty acid was additionally formed. 16S rDNA sequence analysis identified Syntrophospora and Syntrophomonas spp. as closest phylogenetic neighbors.

Describing Case Study Method and Identifying the Factors that Contribute to the Successful Conduct of Case Studies

OpenAIRE

Ahmad H. Juma'h; Mustafa Cavus

2001-01-01

This article has attempted to describe case study, the limitations and critiques on case study methodology and how the proponents have responded to these. Our special focus have been on the debate on theory building from case study research, and a framework for conducting case study research as well as the factors for a successful case study research. The overall conclusion is that the case study has been inappropriately used to generate theories.

How To Set Up Your Own Small Business. Service Company Case Study. Manufacturing Firm Case Study. Retail Store Case Study.

Science.gov (United States)

Fallek, Max

This collection of case studies is intended for use in a course in setting up a small business. The first, a case study of the process of setting up a service company, covers analyzing the pros and cons of starting one's own business, assessing the competition and local market, and selecting a site for and financing the business. The principal…

Theory Testing Using Case Studies

DEFF Research Database (Denmark)

Møller, Ann-Kristina Løkke; Dissing Sørensen, Pernille

2014-01-01

The appropriateness of case studies as a tool for theory testing is still a controversial issue, and discussions about the weaknesses of such research designs have previously taken precedence over those about its strengths. The purpose of the paper is to examine and revive the approach of theory...... testing using case studies, including the associated research goal, analysis, and generalisability. We argue that research designs for theory testing using case studies differ from theorybuilding case study research designs because different research projects serve different purposes and follow different...... research paths....

Quantitative Metaproteomics Highlight the Metabolic Contributions of Uncultured Phylotypes in a Thermophilic Anaerobic Digester.

Science.gov (United States)

Hagen, Live H; Frank, Jeremy A; Zamanzadeh, Mirzaman; Eijsink, Vincent G H; Pope, Phillip B; Horn, Svein J; Arntzen, Magnus Ø

2017-01-15

In this study, we used multiple meta-omic approaches to characterize the microbial community and the active metabolic pathways of a stable industrial biogas reactor with food waste as the dominant feedstock, operating at thermophilic temperatures (60°C) and elevated levels of free ammonia (367 mg/liter NH 3 -N). The microbial community was strongly dominated (76% of all 16S rRNA amplicon sequences) by populations closely related to the proteolytic bacterium Coprothermobacter proteolyticus. Multiple Coprothermobacter-affiliated strains were detected, introducing an additional level of complexity seldom explored in biogas studies. Genome reconstructions provided metabolic insight into the microbes that performed biomass deconstruction and fermentation, including the deeply branching phyla Dictyoglomi and Planctomycetes and the candidate phylum "Atribacteria" These biomass degraders were complemented by a synergistic network of microorganisms that convert key fermentation intermediates (fatty acids) via syntrophic interactions with hydrogenotrophic methanogens to ultimately produce methane. Interpretation of the proteomics data also suggested activity of a Methanosaeta phylotype acclimatized to high ammonia levels. In particular, we report multiple novel phylotypes proposed as syntrophic acetate oxidizers, which also exert expression of enzymes needed for both the Wood-Ljungdahl pathway and β-oxidation of fatty acids to acetyl coenzyme A. Such an arrangement differs from known syntrophic oxidizing bacteria and presents an interesting hypothesis for future studies. Collectively, these findings provide increased insight into active metabolic roles of uncultured phylotypes and presents new synergistic relationships, both of which may contribute to the stability of the biogas reactor. Biogas production through anaerobic digestion of organic waste provides an attractive source of renewable energy and a sustainable waste management strategy. A comprehensive understanding

Theory testing using case studies

DEFF Research Database (Denmark)

Dissing Sørensen, Pernille; Løkke Nielsen, Ann-Kristina

2006-01-01

on the strengths of theory-testing case studies. We specify research paths associated with theory testing in case studies and present a coherent argument for the logic of theoretical development and refinement using case studies. We emphasize different uses of rival explanations and their implications for research...... design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive......Case studies may have different research goals. One such goal is the testing of small-scale and middle-range theories. Theory testing refers to the critical examination, observation, and evaluation of the 'why' and 'how' of a specified phenomenon in a particular setting. In this paper, we focus...

Five Misunderstandings About Case-Study Research

DEFF Research Database (Denmark)

Flyvbjerg, Bent

2006-01-01

This article examines five common misunderstandings about case-study research: (a) theoretical knowledge is more valuable than practical knowledge; (b) one cannot generalize from a single case, therefore, the single-case study cannot contribute to scientific development; (c) the case study is most...... useful for generating hypotheses, whereas other methods are more suitable for hypotheses testing and theory building; (d) the case study contains a bias toward verification; and (e) it is often difficult to summarize specific case studies. This article explains and corrects these misunderstandings one...

Fuzzy-Set Case Studies

Science.gov (United States)

Mikkelsen, Kim Sass

2017-01-01

Contemporary case studies rely on verbal arguments and set theory to build or evaluate theoretical claims. While existing procedures excel in the use of qualitative information (information about kind), they ignore quantitative information (information about degree) at central points of the analysis. Effectively, contemporary case studies rely on…

Case Study: Guidelines for Producing Videos to Accompany Flipped Cases

Science.gov (United States)

Prud'homme-Généreux, Annie; Schiller, Nancy A.; Wild, John H.; Herreid, Clyde Freeman

2017-01-01

Three years ago, the "National Center for Case Study Teaching in Science" (NCCSTS) was inspired to merge the case study and flipped classroom approaches. The resulting project aimed to create the materials required to teach a flipped course in introductory biology by assigning videos as homework and case studies in the classroom. Three…

Five misunderstandings about case study research

DEFF Research Database (Denmark)

Flyvbjerg, Bent

2004-01-01

This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without exemplars is an ineffective one. Social science may be strengthened by the execution of more...

Case Study: A Picture Worth a Thousand Words? Making a Case for Video Case Studies

Science.gov (United States)

Pai, Aditi

2014-01-01

A picture, they say, is worth a thousand words. If a mere picture is worth a thousand words, how much more are "moving pictures" or videos worth? The author poses this not merely as a rhetorical question, but because she wishes to make a case for using videos in the traditional case study method. She recommends four main approaches of…

Five misunderstandings about Case-study Research

DEFF Research Database (Denmark)

Flyvbjerg, Bent

This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without  exemplars is an ineffective one. Social science may be strengthened by the execution of more...

Theoretical pluralism in psychoanalytic case studies.

Science.gov (United States)

Willemsen, Jochem; Cornelis, Shana; Geerardyn, Filip M; Desmet, Mattias; Meganck, Reitske; Inslegers, Ruth; Cauwe, Joachim M B D

2015-01-01

The aim of this study is to provide an overview of the scientific activity of different psychoanalytic schools of thought in terms of the content and production of case studies published on ISI Web of Knowledge. Between March 2013 and November 2013, we contacted all case study authors included in the online archive of psychoanalytic and psychodynamic case studies (www.singlecasearchive.com) to inquire about their psychoanalytic orientation during their work with the patient. The response rate for this study was 45%. It appears that the two oldest psychoanalytic schools, Object-relations psychoanalysis and Ego psychology or "Classical psychoanalysis" dominate the literature of published case studies. However, most authors stated that they feel attached to two or more psychoanalytic schools of thought. This confirms that the theoretical pluralism in psychoanalysis stretches to the field of single case studies. The single case studies of each psychoanalytic school are described separately in terms of methodology, patient, therapist, or treatment features. We conclude that published case studies features are fairly similar across different psychoanalytic schools. The results of this study are not representative of all psychoanalytic schools, as some do not publish their work in ISI ranked journals.

Theoretical pluralism in psychoanalytic case studies

Science.gov (United States)

Willemsen, Jochem; Cornelis, Shana; Geerardyn, Filip M.; Desmet, Mattias; Meganck, Reitske; Inslegers, Ruth; Cauwe, Joachim M. B. D.

2015-01-01

The aim of this study is to provide an overview of the scientific activity of different psychoanalytic schools of thought in terms of the content and production of case studies published on ISI Web of Knowledge. Between March 2013 and November 2013, we contacted all case study authors included in the online archive of psychoanalytic and psychodynamic case studies (www.singlecasearchive.com) to inquire about their psychoanalytic orientation during their work with the patient. The response rate for this study was 45%. It appears that the two oldest psychoanalytic schools, Object-relations psychoanalysis and Ego psychology or “Classical psychoanalysis” dominate the literature of published case studies. However, most authors stated that they feel attached to two or more psychoanalytic schools of thought. This confirms that the theoretical pluralism in psychoanalysis stretches to the field of single case studies. The single case studies of each psychoanalytic school are described separately in terms of methodology, patient, therapist, or treatment features. We conclude that published case studies features are fairly similar across different psychoanalytic schools. The results of this study are not representative of all psychoanalytic schools, as some do not publish their work in ISI ranked journals. PMID:26483725

Bioremediation case studies: Abstracts. Final report

International Nuclear Information System (INIS)

Devine, K.

1992-03-01

The report contains abstracts of 132 case studies of bioremediation technology applied to hazardous waste clean-up. It was prepared to compile bioremediation studies in a variety of locations and treating diverse contaminants, most of which were previously undocumented. All data are based on vendor-supplied information and there was no opportunity to independently confirm its accuracy. These 132 case studies, from 10 different biotechnology companies, provide users with reference information about on-going and/or completed field applications and studies. About two-thirds of the cases were at full-scale clean-up level with the remainder at pilot or laboratory scale. In 74 percent of the cases, soil was at least one of the media treated. Soil alone accounts for 46 percent of the cases. Petroleum-related wastes account for the largest contaminant with 82 cases. Thirty-one states are represented in the case studies

451 Case studies Cardiac

African Journals Online (AJOL)

Marinda

Case Studies. 29 ... A case of a 26-year-old ASA I physical status male undergoing septoplasty had an abrupt ... myocardial infarction, severe hypertensive crisis, cerebral .... or no formal management is required in an ASA I patient.8 One.

CASE STUDY

African Journals Online (AJOL)

2011-06-02

Jun 2, 2011 ... immunosuppression associated with HIV/AIDS puts them at a higher risk of developing oesophageal cancer. 47. CASE STUDY. A 49-year-old man was diagnosed as HIV infected, with a CD4 count of 60 cells/µl. He was started on an antiretroviral treatment regimen comprising zidovudine, lamivudine and ...

Casing study

Energy Technology Data Exchange (ETDEWEB)

Roche, P.

2000-12-01

An unorthodox method of casing drilling used by Tesco Corporation at a gas well in Wyoming to drill deeper using casings as drillpipe is discussed. The process involves either rotating the casing as drill string or using a downhole mud motor to rotate the bit. In this instance, the surface hole and the production hole were casing-drilled to a record 8,312 feet by rotating the casing. The 8 1/2-inch surface hole was drilled with 7-inch casing to 1,200 feet using a Tesco underreamer and a polycrystalline pilot bit; drilling and cementing was completed in 12 1/2 hours. The 6 1/4-inch production hole was drilled with 4 1/2-inch casing and the bottomhole assembly was retrieved after 191 hours rotating. This case was the first in which the entire well was casing-drilled from surface to TD. Penetration rate compared favorably with conventional methods: 12 1/2 hours for casing-drilling to 18.9 hours for conventional drilling, despite the fact that the casing-drilling technology is still in its infancy. It is suggested that casing-drilling has the potential to eliminate the need for the drillpipe entirely. If these expectations were to be realised, casing-drilling could be one of the most radical drilling changes in the history of the oil and gas industry. 1 photo.

MRI case studies

International Nuclear Information System (INIS)

Huggett, S.; Barber, J.

1989-01-01

Three case studies are presented to show the value of magnetic resonance imaging used in conjunction with other imaging techniques. In each case MRI proved a vital diagnostic tool and superior to CT in showing firstly the haematoma in a patient with aphasia and right-sided weakness, secondly the size of the disc herniation in a patient with severe leg and ankle pains and thirdly the existence of a metastatic lesion in a patient with a previous history of breast cancer. 11 figs

Qualitative Case Study Guidelines

Science.gov (United States)

2013-11-01

Introduction to Sociological Methods. 2nd ed. New York, McGraw-Hill 14. Denzin , N. K. and Lincoln , Y. S. (2011) The SAGE Handbook of Qualitative...The Art of Science. In: Denzin , N. K. and Lincoln , Y. S. (eds.) Handbook of Qualitative Research. Thousand Oaks, Sage 19. GAO (1990) Case Study...Rinehart & Winston 39. Stake, R. E. (1994) Case Studies. In: Denzin , N. K. and Lincoln , Y. S. (eds.) Handbook of Qualitative Research. Thousand Oaks, Sage

A review on the bioenergetics of anaerobic microbial metabolism close to the thermodynamic limits and its implications for digestion applications.

Science.gov (United States)

Leng, Ling; Yang, Peixian; Singh, Shubham; Zhuang, Huichuan; Xu, Linji; Chen, Wen-Hsing; Dolfing, Jan; Li, Dong; Zhang, Yan; Zeng, Huiping; Chu, Wei; Lee, Po-Heng

2018-01-01

The exploration of the energetics of anaerobic digestion systems can reveal how microorganisms cooperate efficiently for cell growth and methane production, especially under low-substrate conditions. The establishment of a thermodynamically interdependent partnership, called anaerobic syntrophy, allows unfavorable reactions to proceed. Interspecies electron transfer and the concentrations of electron carriers are crucial for maintaining this mutualistic activity. This critical review summarizes the functional microorganisms and syntroph partners, particularly in the metabolic pathways and energy conservation of syntrophs. The kinetics and thermodynamics of propionate degradation to methane, reversibility of the acetate oxidation process, and estimation of microbial growth are summarized. The various routes of interspecies electron transfer, reverse electron transfer, and Poly-β-hydroxyalkanoate formation in the syntrophic community are also reviewed. Finally, promising and critical directions of future research are proposed. Fundamental insight in the activities and interactions involved in AD systems could serve as a guidance for engineered systems optimization and upgrade. Copyright © 2017 Elsevier Ltd. All rights reserved.

Self-adaption of methane-producing communities to pH disturbance at different acetate concentrations by shifting pathways and population interaction.

Science.gov (United States)

Hao, Liping; Lü, Fan; Li, Lei; Wu, Qing; Shao, Liming; He, Pinjing

2013-07-01

To investigate the competition among acetate-utilizing microorganisms at different acetate levels, bioconversion processes of 50, 100, 150 and 200 mM acetate in the presence and absence of methanogenic inhibitor CH3F were monitored in thermophilic methanogenic system. The successive response of methane-producing community during the deteriorative and recovery phases caused by pH disturbance was analyzed. High acetate concentration (>50mM) inhibited the activity of acetoclastic methanogenesis (AM). The increasing pH (>7.5) enhanced this inhibition. The syntrophic acetate oxidizing (SAO) bacteria and hydrogenotrophic methanogens including Methanomicrobiales and Methanobacteirales were more tolerant to the stress from high acetate concentration and high pH. Resumption from alkali condition to normal pH stimulated the growth of acetate oxidizing syntrophs. The reaction rate of SAO-HM was lower than that of AM. These results point to the possibility to regenerate the deteriorated anaerobic digesters by addition of acclimatized inocula rich in acetate-oxidizing syntrophs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Case Study: The Chemistry of Cocaine

Science.gov (United States)

Dewprashad, Brahmadeo

2011-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's case study focuses on the chemistry of cocaine to teach a number of core concepts in organic chemistry. It also requires that students read and analyze an original research paper on…

The role of radionuclide studies in emergency cases

International Nuclear Information System (INIS)

Nishimura, Tsunehiko; Hayashida, Kohei; Uehara, Toshiisa

1982-01-01

Radionuclide studies have been performed popularly because of its noninvasive and simple method recently. In this study, we applied this technique for the evaluation of emergency cases in cardiovascular diseases. There were 93 cases (1.5%) out of 6163 cases, done during 1981. The subjects were 34 cases of cardiac studies (9 cases of sup(99m)Tc-PYP myocardial imaging, 12 cases of thallium myocardial imaging, 13 cases of cardioangiography), 23 cases of peripheral diseases (12 cases of peripheral angiography, 11 cases of venography), 16 cases of pulmonary imaging, 10 cases of renal studies (6 cases of renal angiography, 9 cases of renal imaging) and 5 cases of brain angiography. These studies were proven to be useful clinically for the evaluation of emergency cases and follow-up studies. In the near future, ''emergency radionuclide studies'' would be benefit for the high-risk patients noninvasively. (author)

eCompetence Case Studies

DEFF Research Database (Denmark)

Jensen, Helle Bækkelund

2006-01-01

In this paper we present some details of the processes undertaken in the European eCompetence Initiative. We present two illustrative and representative case studies. The research aims to identify and understand patterns of individual and organisational eCompetence approaches.......In this paper we present some details of the processes undertaken in the European eCompetence Initiative. We present two illustrative and representative case studies. The research aims to identify and understand patterns of individual and organisational eCompetence approaches....

Case Study Methodology and Homelessness Research

Directory of Open Access Journals (Sweden)

Jill Pable

2013-10-01

Full Text Available This paper describes the potential suitability of case study methodology for inquiry with the homeless population. It references a research study that uses case study research method to build theory. This study's topic is the lived experience of destitute individuals who reside in homeless shelters, and explores the homeless shelter built environment's potential influence on resident satisfaction and recovery. Case study methodology may be appropriate because it explores real-life contextual issues that characterize homelessness and can also accommodate the wide range of homeless person demographics that make this group difficult to study in a generalized fashion. Further, case study method accommodates the need within research in this area to understand individualized treatments as a potential solution for homelessness.

Assembling a Case Study Tool Kit: 10 Tools for Teaching with Cases

Science.gov (United States)

Prud'homme-Généreux, Annie

2017-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. The author shares the strategies and tools that teachers can use to manage a case study classroom effectively.

On misunderstandings in connection with case-studies

DEFF Research Database (Denmark)

Flyvbjerg, Bent

2005-01-01

This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...

Qualitative Case Study Research as Empirical Inquiry

Science.gov (United States)

Ellinger, Andrea D.; McWhorter, Rochell

2016-01-01

This article introduces the concept of qualitative case study research as empirical inquiry. It defines and distinguishes what a case study is, the purposes, intentions, and types of case studies. It then describes how to determine if a qualitative case study is the preferred approach for conducting research. It overviews the essential steps in…

Methodology for the case studies

NARCIS (Netherlands)

Smits, M.J.W.; Woltjer, G.B.

2017-01-01

This document is about the methodology and selection of the case studies. It is meant as a guideline for the case studies, and together with the other reports in this work package can be a source of inform ation for policy officers, interest groups and researchers evaluating or performing impact

Performable Case Studies in Ethics Education.

Science.gov (United States)

Robeson, Richard; King, Nancy M P

2017-09-12

Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry-the creation and performance of short case studies designed specifically to raise bioethics issues for discussion-represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio.

Emotion, Engagement, and Case Studies

Science.gov (United States)

Herreid, Clyde Freeman; Terry, David R.; Lemons, Paula; Armstrong, Norris; Brickman, Peggy; Ribbens, Eric

2014-01-01

Three college faculty taught large general biology classes using case studies and personal response systems (clickers). Each instructor taught the same eight cases in two different sections, except the questions within the cases differed. In one section the questions were lower order (LO) factual inquiries, and in the other they were largely…

Using Correspondence Analysis in Multiple Case Studies

NARCIS (Netherlands)

Kienstra, Natascha; van der Heijden, Peter G.M.

2015-01-01

In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

Using correspondence analysis in multiple case studies

NARCIS (Netherlands)

Kienstra, N.H.H.; van der Heijden, P.G.M.

2015-01-01

In qualitative research of multiple case studies, Miles and Huberman proposed to summarize the separate cases in a so-called meta-matrix that consists of cases by variables. Yin discusses cross-case synthesis to study this matrix. We propose correspondence analysis (CA) as a useful tool to study

Teaching Business French through Case Studies: Presentation of a Marketing Case.

Science.gov (United States)

Federico, Salvatore; Moore, Catherine

The use of case studies as a means for teaching business French is discussed. The approach is advocated because of the realism of case studies, which are based on actual occurrences. Characteristics of a good case are noted: it tells a story, focuses on interest-arousing issues, is set in the past 10 years, permits empathy with the main…

Case Study: Puttin' on the Ritz: How to Put Science into Cases

Science.gov (United States)

Herreid, Clyde Freeman

2017-01-01

There are multiple ways to put science into a case. This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses different ways of presenting science in case studies.

Case Study Observational Research: A Framework for Conducting Case Study Research Where Observation Data Are the Focus.

Science.gov (United States)

Morgan, Sonya J; Pullon, Susan R H; Macdonald, Lindsay M; McKinlay, Eileen M; Gray, Ben V

2017-06-01

Case study research is a comprehensive method that incorporates multiple sources of data to provide detailed accounts of complex research phenomena in real-life contexts. However, current models of case study research do not particularly distinguish the unique contribution observation data can make. Observation methods have the potential to reach beyond other methods that rely largely or solely on self-report. This article describes the distinctive characteristics of case study observational research, a modified form of Yin's 2014 model of case study research the authors used in a study exploring interprofessional collaboration in primary care. In this approach, observation data are positioned as the central component of the research design. Case study observational research offers a promising approach for researchers in a wide range of health care settings seeking more complete understandings of complex topics, where contextual influences are of primary concern. Future research is needed to refine and evaluate the approach.

Beyond Clinical Case Studies in Psychoanalysis: A Review of Psychoanalytic Empirical Single Case Studies Published in ISI-Ranked Journals

Science.gov (United States)

Meganck, Reitske; Inslegers, Ruth; Krivzov, Juri; Notaerts, Liza

2017-01-01

Single case studies are at the origin of both theory development and research in the field of psychoanalysis and psychotherapy. While clinical case studies are the hallmark of psychoanalytic theory and practice, their scientific value has been strongly criticized. To address problems with the subjective bias of retrospective therapist reports and uncontrollability of clinical case studies, systematic approaches to investigate psychotherapy process and outcome at the level of the single case have been developed. Such empirical case studies are also able to bridge the famous gap between academic research and clinical practice as they provide clinically relevant insights into how psychotherapy works. This study presents a review of psychoanalytic empirical case studies published in ISI-ranked journals and maps the characteristics of the study, therapist, patient en therapies that are investigated. Empirical case studies increased in quantity and quality (amount of information and systematization) over time. While future studies could pay more attention to providing contextual information on therapist characteristics and informed consent considerations, the available literature provides a basis to conduct meta-studies of single cases and as such contribute to knowledge aggregation. PMID:29046660

Kinetic and thermodynamic control of butyrate conversion in non-defined methanogenic communities.

Science.gov (United States)

Junicke, H; van Loosdrecht, M C M; Kleerebezem, R

2016-01-01

Many anaerobic conversions proceed close to thermodynamic equilibrium and the microbial groups involved need to share their low energy budget to survive at the thermodynamic boundary of life. This study aimed to investigate the kinetic and thermodynamic control mechanisms of the electron transfer during syntrophic butyrate conversion in non-defined methanogenic communities. Despite the rather low energy content of butyrate, results demonstrate unequal energy sharing between the butyrate-utilizing species (17 %), the hydrogenotrophic methanogens (9-10 %), and the acetoclastic methanogens (73-74 %). As a key finding, the energy disproportion resulted in different growth strategies of the syntrophic partners. Compared to the butyrate-utilizing partner, the hydrogenotrophic methanogens compensated their lower biomass yield per mole of electrons transferred with a 2-fold higher biomass-specific electron transfer rate. Apart from these thermodynamic control mechanisms, experiments revealed a ten times lower hydrogen inhibition constant on butyrate conversion than proposed by the Anaerobic Digestion Model No. 1, suggesting a much stronger inhibitory effect of hydrogen on anaerobic butyrate conversion. At hydrogen partial pressures exceeding 40 Pa and at bicarbonate limited conditions, a shift from methanogenesis to reduced product formation was observed which indicates an important role of the hydrogen partial pressure in redirecting electron fluxes towards reduced products such as butanol. The findings of this study demonstrate that a careful consideration of thermodynamics and kinetics is required to advance our current understanding of flux regulation in energy-limited syntrophic ecosystems.

HYDROGEOLOGIC CASE STUDIES

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Objectivist case study research

DEFF Research Database (Denmark)

Ridder, Hanne Mette Ochsner; Fachner, Jörg

2016-01-01

be achieved through the use of objectivist case study research. The strength of the case study design is that it allows for uncovering or suggesting causal relationships in real-life settings through an intensive and rich collection of data. According to Hilliard (1993), the opposite applies for extensive......In order to comprehend the impact of music therapy or music therapy processes, a researcher might look for an approach where the topic under investigation can be understood within a broader context. This calls for a rich inclusion of data and consequently a limited number of participants and may...... designs, in which a small amount of data is gathered on a large number of subjects. With the richness of data, the intensive design is ―the primary pragmatic reason for engaging in single-case or small N research‖ (p. 374) and for working from an idiographic rather than a nomothetic perspective....

Methodology Series Module 2: Case-control Studies.

Science.gov (United States)

Setia, Maninder Singh

2016-01-01

Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

Catalog of NASA-Related Case Studies

Data.gov (United States)

National Aeronautics and Space Administration — The OCKO has developed over 50 case studies to enhance learning at workshops, training, retreats and conferences. Case studies make mission knowledge attractive and...

Case Study: Let's Get Personal--Putting Personality into Your Cases

Science.gov (United States)

Herreid, Clyde Freeman

2017-01-01

In this case study, the subject for discussion is the need to use teaching notes in order to add personality to case studies. Personality, it is said, is more important than policy, than demographics, than finances, or amorous peccadillos. Personality is essential. It is the interaction of people that capture our interest, yet, the question is…

Case Study of 'moral injury' : Format Dutch Case Studies Project

NARCIS (Netherlands)

Korver, Sjaak; Walton, Martin N.; van Loenen, Guus

2017-01-01

The case study ‘Moral Injury’ traces care provided by a chaplain in a mental health institution to a former military marksman named Hans. Hans was in care at a specialized unit for military veterans with traumas. He sought contact with a chaplain “to set things right with God” and wanted the

Phenotype fingerprinting suggests the involvement of single-genotype consortia in degradation of aromatic compounds by Rhodopseudomonas palustris.

Directory of Open Access Journals (Sweden)

Tatiana V Karpinets

Full Text Available Anaerobic degradation of complex organic compounds by microorganisms is crucial for development of innovative biotechnologies for bioethanol production and for efficient degradation of environmental pollutants. In natural environments, the degradation is usually accomplished by syntrophic consortia comprised of different bacterial species. This strategy allows consortium organisms to reduce efforts required for maintenance of the redox homeostasis at each syntrophic level. Cellular mechanisms that maintain the redox homeostasis during the degradation of aromatic compounds by one organism are not fully understood. Here we present a hypothesis that the metabolically versatile phototrophic bacterium Rhodopseudomonas palustris forms its own syntrophic consortia, when it grows anaerobically on p-coumarate or benzoate as a sole carbon source. We have revealed the consortia from large-scale measurements of mRNA and protein expressions under p-coumarate, benzoate and succinate degrading conditions using a novel computational approach referred as phenotype fingerprinting. In this approach, marker genes for known R. palustris phenotypes are employed to determine the relative expression levels of genes and proteins in aromatics versus non-aromatics degrading condition. Subpopulations of the consortia are inferred from the expression of phenotypes and known metabolic modes of the R. palustris growth. We find that p-coumarate degrading conditions may lead to at least three R. palustris subpopulations utilizing p-coumarate, benzoate, and CO2 and H2. Benzoate degrading conditions may also produce at least three subpopulations utilizing benzoate, CO2 and H2, and N2 and formate. Communication among syntrophs and inter-syntrophic dynamics in each consortium are indicated by up-regulation of transporters and genes involved in the curli formation and chemotaxis. The N2-fixing subpopulation in the benzoate degrading consortium has preferential activation of the

Schematic representation of case study research designs.

Science.gov (United States)

Rosenberg, John P; Yates, Patsy M

2007-11-01

The paper is a report of a study to demonstrate how the use of schematics can provide procedural clarity and promote rigour in the conduct of case study research. Case study research is a methodologically flexible approach to research design that focuses on a particular case - whether an individual, a collective or a phenomenon of interest. It is known as the 'study of the particular' for its thorough investigation of particular, real-life situations and is gaining increased attention in nursing and social research. However, the methodological flexibility it offers can leave the novice researcher uncertain of suitable procedural steps required to ensure methodological rigour. This article provides a real example of a case study research design that utilizes schematic representation drawn from a doctoral study of the integration of health promotion principles and practices into a palliative care organization. The issues discussed are: (1) the definition and application of case study research design; (2) the application of schematics in research; (3) the procedural steps and their contribution to the maintenance of rigour; and (4) the benefits and risks of schematics in case study research. The inclusion of visual representations of design with accompanying explanatory text is recommended in reporting case study research methods.

Peace Corps Water/Sanitation Case Studies and Analyses. Appropriate Technologies for Development. Case Study CS-4.

Science.gov (United States)

Talbert, Diana E., Comp.

This document provides an overview of Peace Corps water and sanitation activities, five case studies (Thailand, Yemen, Paraguay, Sierra Leone, and Togo), programming guidelines, and training information. Each case study includes: (1) background information on the country's geography, population, and economics; (2) information on the country's…

Five case studies of multifamily weatherization programs

Energy Technology Data Exchange (ETDEWEB)

Kinney, L; Wilson, T.; Lewis, G. [Synertech Systems Corp. (United States); MacDonald, M. [Oak Ridge National Lab., TN (United States)

1997-12-31

The multifamily case studies that are the subject of this report were conducted to provide a better understanding of the approach taken by program operators in weatherizing large buildings. Because of significant variations in building construction and energy systems across the country, five states were selected based on their high level of multifamily weatherization. This report summarizes findings from case studies conducted by multifamily weatherization operations in five cities. The case studies were conducted between January and November 1994. Each of the case studies involved extensive interviews with the staff of weatherization subgrantees conducting multifamily weatherization, the inspection of 4 to 12 buildings weatherized between 1991 and 1993, and the analysis of savings and costs. The case studies focused on innovative techniques which appear to work well.

Summary of case studies for cooperation mechanisms

DEFF Research Database (Denmark)

Longa, Francesco Dalla; Klinge Jacobsen, Henrik; Hansen, Lise-Lotte Pade

2012-01-01

This document is a summary report highlighting the main aspect analyzed in the RES4LESS case studies. The document starts with an introductory chapter where the background that led to the selection of the case studies is outlined. In the following three chapters the case studies are presented, hi...

Implementing Product Platforms: A Case Study

DEFF Research Database (Denmark)

Nielsen, Ole Fiil; Mortensen, Niels Henrik

2006-01-01

The paper describes a case study dealing with the process of creating and implementing a product platform. The paper espessially deals with the fact that to obtain the benefits of platforms a permanent change in behaviour in product development must be ensured. This change in behaviour requires...... acceptance and approval from the organisation in general and the commitment from management to enforce agreed-upon decisions. The case study itself was performed in the Danish company LEGO Group. The case study had two objectives: To create a technical architecture and align this architecture...

Location of existing Case Studies on Open Education

OpenAIRE

Burke, Siobhan

2014-01-01

Members of the Open Education Special Interest Group have collected a selection of short case studies on Open Education. View all of the case studies at http://repository.alt.ac.uk/view/divisions/CaseStudies/ Location of existing Case Studies on Open Education: The following lists aims to capture and amalgamate the various different case study sources which have been created and developed within the UK around experiences of Open Educational Resources.

national Case study

African Journals Online (AJOL)

This national case study reports on the development of a national network, ... system under the new policy), tends to be limited by content on problems and ... 20 credit programme; and within two Post Graduate Certificate of Education contexts, ...... descriptive with an issues focus (empirical) towards awareness production to.

Writing case studies in information systems research

NARCIS (Netherlands)

van der Blonk, H.C.

Case study research can be reported in different ways. This paper explores the various ways in which researchers may choose to write down their case studies and then introduces a subsequent typology of writing case studies. The typology is based on a 2 x 2 matrix, resulting in four forms of writing

Elucidation of the pathways of catabolic glutamate conversion in three thermophilic anaerobic bacteria.

Science.gov (United States)

Plugge, C M; van Leeuwen, J M; Hummelen, T; Balk, M; Stams, A J

2001-07-01

The glutamate catabolism of three thermophilic syntrophic anaerobes was compared based on the combined use of [(13)C] glutamate NMR measurements and enzyme activity determinations. In some cases the uptake of intermediates from different pathways was studied. The three organisms, Caloramator coolhaasii, Thermanaerovibrio acidaminovorans and strain TGO, had a different stoichiometry of glutamate conversion and were dependent on the presence of a hydrogen scavenger (Methanobacterium thermoautotrophicum Z245) to a different degree for their growth. C. coolhaasii formed acetate, CO(2), NH(4)(+) and H(2) from glutamate. Acetate was found to be formed through the beta-methylaspartate pathway in pure culture as well as in coculture. T. acidaminovorans converted glutamate to acetate, propionate, CO(2), NH(4)(+) and H(2). Most likely, this organism uses the beta-methylaspartate pathway for acetate formation. Propionate formation occurred through a direct oxidation of glutamate via succinyl-CoA and methylmalonyl-CoA. The metabolism of T. acidaminovorans shifted in favour of propionate formation when grown in coculture with the methanogen, but this did not lead to the use of a different glutamate degradation pathway. Strain TGO, an obligate syntrophic glutamate-degrading organism, formed propionate, traces of succinate, CO(2), NH(4)(+) and H(2). Glutamate was converted to propionate oxidatively via the intermediates succinyl-CoA and methylmalonyl-CoA. A minor part of the succinyl-CoA was converted to succinate and excreted.

The Danish National Case Study Report

DEFF Research Database (Denmark)

Brodersen, Søsser; Jørgensen, Michael Søgaard

Three case studies from Danish science shops within the environmental field are analysed with respect to societal background, interaction between the involved actors and the societal impact of the co-operation. The report is one of the seven national case study reports from the EU...

Using Case Studies in Calculus-based Physics

Science.gov (United States)

Katz, Debora M.

2006-12-01

Do your students believe that the physics only works in your classroom or laboratory? Or do they see that physics underlies their everyday experience? Case studies in physics help students connect physics principles to their everyday experience. For decades, case studies have been used to teach law, medicine and biology, but they are rarely used in physics. I am working on a calculus-based physics textbook for scientists and engineers. Case studies are woven into each chapter. Stop by and get a case study to test out in your classroom. I would love to get your feedback.

Modalities of Generalization Through Single Case Studies.

Science.gov (United States)

Zittoun, Tania

2017-06-01

The value of case studies for theory building is still doubted in psychology. The paper argues for the importance of case studies and the possibility of generalizing from these for a specific sociocultural understanding of human development. The paper first clarifies the notion of abduction within case studies, drawing on pragmatists James and Peirce and expanding it with the work of Lewin, and argues that it is the core mechanism that allows generalization from case studies. The second section presents the possibility of generalizing from individual single case studies, for which not only the subjective perspective, but also the dynamics by which the social and cultural environment guide and enable the person's development, have to be accounted for. The third section elaborates the question of institutional case studies, where the challenge is to account both for institutional dynamics, and for persons' trajectories within; this is exemplified with an ongoing study on the process of obtaining citizenship in Switzerland. The paper briefly concludes by highlighting two possible implications of the paper, one concerning the process of theoretical reasoning, the other, the fact that sociocultural psychology could itself be seen as an institution in-the-making.

Implementation of case studies in undergraduate didactic nursing courses: a qualitative study.

Science.gov (United States)

Dutra, Danette K

2013-07-04

The implementation of unfolding scenario-based case studies in the didactic classroom is associated with learner-centered education. The utilization of learner-centered pedagogies, such as case studies, removes the focus from the instructor and instead places it on the student. Learner-centered pedagogies are believed to improve students' levels of cognition. The purpose of this study was to examine how nurse educators are implementing the pedagogies of case studies in their undergraduate didactic courses. The goal was to examine, document, report, and, ultimately, implement the strategies. Purposeful sampling was utilized in this qualitative, multisite-designed study. For each of the four participants, three separate site visits were completed. Observations and post-observational interviews took place at each site visit. Transcribed data from interviews, observations, and course documents were imported into the computer program Nvivo8. Repetitive comparative analysis was utilized to complete the data coding process. The guiding research question of this study sought to investigate the implementation strategies of case studies in didactic nursing courses. The implementation of case studies by the participants reflected two primary patterns: Formal Implementation (FI) and Informal Implementation (II) of case studies. The FI of case studies was further divided into two subcategories: Formal Implementation of case studies used Inside the Classroom setting (FIIC) and Formal Implementation of cases studies used Outside of the Classroom (FIOC). Results of this investigation have led to an increased understanding of implementation strategies of unfolding scenario-based case studies in undergraduate nursing didactic courses. Data collected were rich in the description of specific methodologies for utilization of case studies and may serve as a resource for faculty in development of creative strategies to enhance the didactic classroom experience.

Using Case Studies to Enrich Field Experience.

Science.gov (United States)

Florio-Ruane, Susan; Clark, Christopher M.

1990-01-01

This paper discusses the use of field experience in teacher education and how it can be augmented by phenomenological case studies. It summarizes a particular case study involving three teacher education classes, noting that reflective analysis of cases can prepare students to observe in the field. (SM)

Using Case Studies to Teach About Global Issues, Bali: A Case Study

Science.gov (United States)

Oswald, James M.

1974-01-01

The South Pacific island of Bali is used as a case study of overpopulation and food shortage. A brief description of the resources, the typical lifestyle of the Balinese farmer, and possible teaching techniques are given. (DE)

Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.

Science.gov (United States)

Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

2017-06-05

Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. Published by Elsevier Ltd.

Septic Systems Case Studies

Science.gov (United States)

A collection of septic systems case studies to help community planners, elected officials, health department staff, state officials, and interested citizens explore alternatives for managing their decentralized wastewater treatment systems.

Contextualising case studies in entrepreneurship: A tandem approach to conducting a longitudinal cross-country case study

DEFF Research Database (Denmark)

Chetty, S. K.; Partanen, J.; Rasmussen, Erik Stavnsager

2014-01-01

Using predictive and effectuation logics as a framework, this research note explains how case study research was conducted to demonstrate rigour and relevance. The study involves a longitudinal cross-country case study on small and medium-sized firm growth and networks undertaken by research teams...... in three countries (Finland, Denmark and New Zealand) involving 33 firms. This research note outlines the implications of this research and provides valuable guidance and reflections upon opportunities for future research regarding the conduct of contextual studies in entrepreneurship without compromising...

Case Study Research: Foundations and Methodological Orientations

Directory of Open Access Journals (Sweden)

Helena Harrison

2017-01-01

Full Text Available Over the last forty years, case study research has undergone substantial methodological development. This evolution has resulted in a pragmatic, flexible research approach, capable of providing comprehensive in-depth understanding of a diverse range of issues across a number of disciplines. Change and progress have stemmed from parallel influences of historical transformations in approaches to research and individual researcher's preferences, perspectives, and interpretations of this design. Researchers who have contributed to the development of case study research come from diverse disciplines with different philosophical perspectives, resulting in a variety of definitions and approaches. For the researcher new to using case study, such variety can create a confusing platform for its application. In this article, we explore the evolution of case study research, discuss methodological variations, and summarize key elements with the aim of providing guidance on the available options for researchers wanting to use case study in their work. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1701195

Case studies on age-management in organisations: report on organisational case studies

NARCIS (Netherlands)

Punte, E.; Conen, W.S.; Schippers, J.; Henkens, C.J.I.M.

2011-01-01

The acquisition of case studies was thwarted by the economic crisis and the feeling of being ‘over-researched’ by potential organisations. Although organisations in some sectors (e.g. chemical manufacturing) reported the worst part of the economic crisis was behind, many organisations indicated

Case Study: What Makes a Good Case, Revisited: The Survey Monkey Tells All

Science.gov (United States)

Herried, Clyde Freeman; Prud'homme-Genereux, Annie; Schiller, Nancy A.; Herreid, Ky F.; Wright, Carolyn

2016-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. In this month's issue the authors provide a more definitive answer to the "What Makes a Good Case?" question based on a just-completed Survey Monkey survey given to NCCSTS teachers.

Associative visual agnosia: a case study.

Science.gov (United States)

Charnallet, A; Carbonnel, S; David, D; Moreaud, O

2008-01-01

We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study, an alternative account in the framework of (non abstractive) episodic models of memory.

Case Study on Logistics Performance

Directory of Open Access Journals (Sweden)

Shahryar Sorooshian

2013-05-01

Full Text Available The paper presents research carried out at a medium‐size manufacturing organization in east Asia. The study tries to highlight the importance of supply chain management; specifically, our aim for this study is to understand logistics and performance measurement in the logistics and supply chain, and we include a theoretical discussion of online data collected and a case study of the logistic performance of a real organization. The study also examines the performance of the selected company, identifies the problems and provides recommendations for improvements. This study can be a guide for business advisers and those interested in analysing company performance, especially from a logistics viewpoint. We also suggest the methodology of this case study for those who want to have a better understanding of a business environment before starting their own business, or for benchmarking practice during strategic planning.

CASE STUDY

African Journals Online (AJOL)

HIV infection has several oral manifestations, including oral candidiasis and oral hairy leucoplakia. Occasionally unusual presentations requiring rigorous investigations are seen, and in these cases the diagnosis sometimes remains a dilemma owing to limited investigation facilities.1-3 We present the case of a patient who.

A Psychobiographical Case Study

African Journals Online (AJOL)

man, and cancer fighter. This psychobiographical case study entailed a psychosocial-historical ... does not draw more attention as a research method, as this approach has .... of the applied Levinsonian theory to the life of Jobs against the ...

Associative Visual Agnosia: A Case Study

Directory of Open Access Journals (Sweden)

A. Charnallet

2008-01-01

Full Text Available We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study [1], an alternative account in the framework of (non abstractive episodic models of memory [4].

Associative Visual Agnosia: A Case Study

OpenAIRE

Charnallet, A.; Carbonnel, S.; David, D.; Moreaud, O.

2008-01-01

We report a case of massive associative visual agnosia. In the light of current theories of identification and semantic knowledge organization, a deficit involving both levels of structural description system and visual semantics must be assumed to explain the case. We suggest, in line with a previous case study [1], an alternative account in the framework of (non abstractive) episodic models of memory [4].

Nanomaterial Case Studies: Nanoscale Titanium Dioxide ...

Science.gov (United States)

This draft document presents two case studies of nanoscale titanium dioxide (nano-TiO2) used (1) to remove arsenic from drinking water and (2) as an active ingredient in topical sunscreen. The draft case studies are organized around a comprehensive environmental assessment approach that combines a product life cycle framework with the risk assessment paradigm. The document does not draw conclusions about potential risks. Rather, the case studies are intended to help identify what needs to be known in order to conduct a comprehensive environmental assessment of the potential risks related to nano-TiO2. This draft document is part of a process that will inform the development of EPA’s research strategy to support nanomaterial risk assessments. The complex properties of various nanomaterials make evaluating them in the abstract or with generalizations difficult if not impossible. Thus, this document focuses on two specific uses of nano-TiO2, as a drinking water treatment and as topical sunscreen. These case studies do not represent completed or even preliminary assessments; rather, they present the structure for identifying and prioritizing research needed to support future assessments.

Syntrophomonas zehnderi sp. nov., an anaerobe that degrades long-chain fatty acids in co-culture with Methanobacterium formicicum.

Science.gov (United States)

Sousa, Diana Z; Smidt, Hauke; Alves, M Madalena; Stams, Alfons J M

2007-03-01

An anaerobic, mesophilic, syntrophic fatty-acid-oxidizing bacterium, designated strain OL-4(T), was isolated as a co-culture with Methanobacterium formicicum DSM 1535(NT) from an anaerobic expanded granular sludge bed reactor used to treat an oleate-based effluent. Strain OL-4(T) degraded oleate, a mono-unsaturated fatty acid, and straight-chain fatty acids C(4 : 0)-C(18 : 0) in syntrophic association with Methanobacterium formicicum DSM 1535(NT). Even-numbered fatty acids were degraded to acetate and methane whereas odd-numbered fatty acids were degraded to acetate, propionate and methane. Branched-chain fatty acids were not degraded. The bacterium could not grow axenically with any other substrate tested and therefore is considered to be obligately syntrophic. Fumarate, sulfate, thiosulfate, sulfur and nitrate could not serve as electron acceptors for strain OL-4(T) to degrade oleate or butyrate. Cells of strain OL-4(T) were curved rods, formed spores and showed a variable response to Gram staining. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain OL-4(T) was most closely related to the fatty-acid-oxidizing, syntrophic bacterium Syntrophomonas sp. TB-6 (95 % similarity), Syntrophomonas wolfei subsp. wolfei DSM 2245(T) (94 % similarity) and Syntrophomonas erecta DSM 16215(T) (93 % similarity). In addition to this moderate similarity, phenotypic and physiological characteristics, such as obligate syntrophy, spore formation and utilization of a broader substrate range, differentiated strain OL-4(T) from these Syntrophomonas species. Therefore strain OL-4(T) represents a novel species, for which the name Syntrophomonas zehnderi sp. nov. is proposed. The type strain is OL-4(T) (=DSM 17840(T)=JCM 13948(T)).

Case-control studies in diabetes. Do they really use a case-control design?

Science.gov (United States)

Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

2017-07-01

Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

Educational Potential of Case-Study Technology

OpenAIRE

Fedorinova, Zoya; Vorobeva, Victoria; Malyanova, Marina

2015-01-01

This article presents the results of phenomenological and typological analysis of case-study technology educational potential. The definition “educational potential of case-study technology” is given, the main characteristics of which are changed in communication and collaborative activity quality, appearance of educational initiatives, change of participants’ position in learning process, formation of “collective subject” in collaborative activity, increase of learning (subject) results. Dep...

Case Studies - Cervical Cancer

Centers for Disease Control (CDC) Podcasts

Dr. Alan Waxman, a professor of obstetrics and gynecology at the University of New Mexico and chair of the American College of Obstetricians and Gynecologists (ACOG) committee for the underserved, talks about several case studies for cervical cancer screening and management.

Nuclear forensics case studies

International Nuclear Information System (INIS)

Fedchenko, Vitaly

2016-01-01

The objective of this presentation is to share three case studies from the Institute of Transuranium Elements (ITU) which describe the application of nuclear forensics to events where nuclear and other radioactive material was found to be out of regulatory control

Case study - Czechoslovakia

International Nuclear Information System (INIS)

Kovar, P.

1986-01-01

In the lecture Case Study - Czechoslovakia with the sub-title 'Unified System of Personnel Preparation for Nuclear Programme in Czechoslovakia' the actual status and the current experience of NPP personnel training and preparation in Czechoslovakia are introduced. The above mentioned training system is presented and demonstrated by the story of a proxy person who is going to become shift engineer in a nuclear power plant in Czechoslovakia. (orig./HP)

A genomic view on syntrophic versus non-syntrophic lifestyle in anaerobic fatty acid degrading communities

NARCIS (Netherlands)

Worm, P.; Koehorst, J.J.; Visser, M.; Sedano Nunez, V.T.; Schaap, P.J.; Plugge, C.M.; Sousa, D.Z.; Stams, A.J.M.

2014-01-01

In sulfate-reducing and methanogenic environments complex biopolymers are hydrolyzed and degraded by fermentative micro-organisms that produce hydrogen, carbon dioxide and short chain fatty acids. Degradation of short chain fatty acids can be coupled to methanogenesis or to sulfate-reduction. Here

Using Case Studies to Teach Courtesy Strategies.

Science.gov (United States)

Moore, Patrick

1990-01-01

Explains some courtesy techniques that technical professionals can use to deal with interpersonal problems that arise in writing situations. Presents three case studies with sample responses to show how case studies can teach these courtesy strategies to technical writing students. (MM)

Patterned genital injury in cases of rape - A case-control study

DEFF Research Database (Denmark)

Astrup, Birgitte Schmidt; Ravn, Pernille; Thomsen, Jørgen Lange

2013-01-01

A pattern of genital injury that separates trauma seen in sexual assault cases from trauma seen following consensual sexual intercourse has been a matter of debate. This study aimed at clarifying the question by eliminating as many confounders as possible in a prospective, case-control setup. A t...

Mathematical modelling with case studies using Maple and Matlab

CERN Document Server

Barnes, B

2014-01-01

Introduction to Mathematical ModelingMathematical models An overview of the book Some modeling approaches Modeling for decision makingCompartmental Models Introduction Exponential decay and radioactivity Case study: detecting art forgeries Case study: Pacific rats colonize New Zealand Lake pollution models Case study: Lake Burley Griffin Drug assimilation into the blood Case study: dull, dizzy, or dead? Cascades of compartments First-order linear DEs Equilibrium points and stability Case study: money, money, money makes the world go aroundModels of Single PopulationsExponential growth Density-

Making a case for case studies in psychotherapy training

DEFF Research Database (Denmark)

Mackrill, Thomas Edward; Iwakabe, Shigeru

2013-01-01

articulated explicitly or researched systematically in spite of its cardinal importance. An analysis of the role of case studies in psychotherapy training is presented. Reading, watching, or hearing about cases can offer novice psychotherapists access to a closed world; access to psychological theory...... in action; access to whole courses of therapy; access to different approaches; access to significant moments; access to the therapeutic relationship; access to a wide range of client types; access to working in different contexts; and the opportunity of identifying with therapists and clients. Writing...

Towards More Case Study Research in Entrepreneurship

Directory of Open Access Journals (Sweden)

Tom Duxbury

2012-03-01

Full Text Available Entrepreneurship as an emerging discipline has made good strides, but according to some, has fallen short of bringing its theory and literature up to the standards of others in the management sciences. Rich with the descriptive detail needed for insightful theory building in entrepreneurship, scholars have called for more case study research, particularly those incorporating non-retrospective and longitudinal observations. At the same time however, it has become rare to find such research published in A-level journals dedicated to entrepreneurship. A survey presented here of major entrepreneurship journals over the past six years revealed a publication rate of only 3% using the case study method. This presents a major impediment for developing fresh research in this field based upon the study of real cases. The author explores how the case study method has been applied to entrepreneurship research and provides recommendations for improved publication rates.

Identification of Ambiguity in the Case Study Research Typology

DEFF Research Database (Denmark)

Grünbaum, Niels Nolsøe

2015-01-01

. Relevant to varied levels and scales of case study use, the aim of this collection is to provide readers with a comprehensive overview of where we are now with case study research, so that they may better judge their own applications of the case study. From definitions to interdisciplinary methods......The purpose of this four volume collection is to provide an accessible selection of the best writing on case study in the English language internationally. Such a collection is timely and highly relevant to students, researchers and academics in higher education, especially when the case......, this set will address the practical case study by offering a structured selection of some of the best modern and classic writing on the case study in article form, together with a synoptic editorial introduction and overview of the field of research....

Present status and problems of radionuclide studies in emergency cases

International Nuclear Information System (INIS)

Ogawa, Kiyoshi

1983-01-01

Scintigraphy is just right for diagnosing emergency cases due to its noninvasive and simple method, but emergency radionuclide studies have not become practical as a result of difficulty problems. Recently, nuclear medical devices have become easier to use in operations. It is become of this, that I have submitted this report regarding the problems of radionuclide studies in emergency cases. There were 101 cases (1.4 %) out of 7,310 cases for the year period Sept. 1981 - Aug. 1982. The studies consisted of 12 brain imaging cases, 9 plumonary imaging cases, 22 cardiac study cases (cardio-angiography cases 8, 99m-Tc-PYP myocardium imaging cases 12, 201-Tl myocardium imaging cases 2), 12 renal study cases, 11 G.I. blood loss cases, 35 peripheral angiography cases. In the near future, we will have to be ready to perform emergency radionuclide studies if the need arises. (author)

SCA12 case study

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 88; Issue 1. Utilizing linkage disequilibrium information from Indian Genome Variation Database for mapping mutations: SCA12 case study. Samira Bahl Ikhlak Ahmed The Indian Genome Variation Consortium Mitali Mukerji. Research Article Volume 88 Issue 1 April 2009 pp 55- ...

Deep Attack Weapons Mix Study (DAWMS) Case Study

National Research Council Canada - National Science Library

Bexfield, James

2001-01-01

.... This report describes the process used to conduct the Deep Attack Weapons Mix Study (DAWMS) in 1995-1997. This case study focuses on the weapons being procured by the Services and whether a joint viewpoint would result in a more effective mix...

Reverse logistics: A review of case studies

NARCIS (Netherlands)

Brito, de M.P.; Dekker, Rommert; Flapper, S.D.P.; Fleischmann, B.; Klose, A.

2004-01-01

This paper gives an overview of scientific literature that describes and discusses cases of reverse logistics activities in practice. Over sixty case studies are considered. Based on these studies we are able to indicate critical factors for the practice of reverse logistics. In addition we compare

Reverse case study: to think like a nurse.

Science.gov (United States)

Beyer, Deborah A

2011-01-01

Reverse case study is a collaborative, innovative, active learning strategy that nurse educators can use in the classroom. Groups of students develop a case study and a care plan from a list of medications and a short two- to three-sentence scenario. The students apply the nursing process to thoroughly develop a complete case study written as a concept map. The strategy builds on previous learned information and applies the information to new content, thus promoting critical thinking and problem solving. Reverse case study has been used in both associate and baccalaureate nursing degree theory courses to generate discussion and assist students in thinking like a nurse. 2011, SLACK Incorporated.

Case Study - Alpha

Directory of Open Access Journals (Sweden)

Stephen Leybourne

2016-11-01

Full Text Available This case study was developed from an actual scenario by Dr. Steve Leybourne of Boston University.  The case documents the historical evolution of an organization, and has been used successfully in courses dealing with organizational and cultural change, and the utilization of ‘soft skills’ in project-based management. This is a short case, ideal for classroom use and discussion.  The issues are easily accessible to students, and there is a single wide ranging question that allows for the inclusion of many issues surrounding strategic decision-making, and behavioural and cultural change. Alpha was one of the earlier companies in the USA to invest in large, edge-of-town superstores, with plentiful free vehicle parking, selling food and related household products. Alpha was created in the 1950s as a subsidiary of a major publicly quoted retail group.  It started business by opening a string of very large discount stores in converted industrial and warehouse premises in the south of the United States. In the early days shoppers were offered a limited range of very competitively priced products. When Alpha went public in 1981 it was the fourth largest food retailer in the US, selling an ever-widening range of food and non-food products.  Its success continued to be based on high volume, low margins and good value for money, under the slogan of ‘Alpha Price.’

The Effect of Using Case Studies in Business Statistics

Science.gov (United States)

Pariseau, Susan E.; Kezim, Boualem

2007-01-01

The authors evaluated the effect on learning of using case studies in business statistics courses. The authors divided students into 3 groups: a control group, a group that completed 1 case study, and a group that completed 3 case studies. Results evidenced that, on average, students whom the authors required to complete a case analysis received…

CAREM X INPRO case study

International Nuclear Information System (INIS)

Florido, P.C.; Brasnarof, D.; Delmastro, D.; Azpitarte, O.E.

2004-01-01

In order to assess and compare the performance of innovative nuclear energy systems INPRO has defined a set of basic principles, user requirements and criteria to be met in different areas (economics, sustainability and environment, safety, waste management and proliferation). This paper illustrates the use of INPRO methodology to a particular reactor system. Argentina is performing CAREM X Nuclear System Case Study based on CAREM nuclear reactor and Once Through Fuel Cycle, using SIGMA for enriched uranium production, and a deep geological repository for final disposal of high level waste after surface intermediate storage in horizontal natural convection silos, to verify INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) methodology. 6 aspects have been considered: 1) enrichment based on Sigma enrichment plant (gas diffusion technology), 2) conversion to UO 2 , 3) fuel manufacturing, 4) CAREM-300 based reactor technology, 5) intermediate spent fuel storage, and 6) deep geological repository of spent fuels. Projections show that developing countries could play a crucial role in the deployment of nuclear energy, in the next fifty years. This case study will be highly useful for checking INPRO methodology for this scenario. In this paper, the preliminary findings of the Case Study are presented, including proposals to improve the INPRO methodology

A Case Study of "Empathetic Teaching Artistry"

Science.gov (United States)

Risner, Doug

2014-01-01

This case study is one of twenty cases derived from Anderson and Risner's international study of teaching artists in dance, and theatre, which investigated participants' (n=172) artistic and academic preparation in dance, and theatre, initial entry into the teaching artist field, rewards, challenges, and obstacles in participants' work, artists'…

Study on Case Teaching of Financial Management

Science.gov (United States)

Che, Zhenghong; Che, Zhengmei

2011-01-01

Case teaching is an efficient teaching method of management. It plays an important role to enhance the students' ability to practice the theory. However, case teaching of financial management has not achieved the expected results. The paper aims to study the importance, characteristics and corresponding methods of case teaching method of financial…

Case studies in atomic collision physics

CERN Document Server

McDaniel, E W

1974-01-01

Case Studies in Atomic Physics III focuses on case studies on atomic and molecular physics, including atomic collisions, transport properties of electrons, ions, molecules, and photons, interaction potentials, spectroscopy, and surface phenomena. The selection first discusses detailed balancing in the time-dependent impact parameter method, as well as time-reversal in the impact parameter method and coupled state approximation. The text also examines the mechanisms of electron production in ion. Topics include measurement of doubly differential cross sections and electron spectra, direct Coul

Music in context : Four case studies

NARCIS (Netherlands)

Randwijck, R.J.C. van

2008-01-01

In his thesis entitled “Music in Context. Four Case Studies”, R.J.C. van Randwijck investigates the context in which music has been created. It is a search in Four Case Studies, approaching four pieces of music from the context in which they were written in order to understand their meaning. The

Theory Testing Using Case Studies

DEFF Research Database (Denmark)

Sørensen, Pernille Dissing; Løkke, Ann-Kristina

2006-01-01

design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive...

Rigour in qualitative case-study research.

Science.gov (United States)

Houghton, Catherine; Casey, Dympna; Shaw, David; Murphy, Kathy

2013-03-01

To provide examples of a qualitative multiple case study to illustrate the specific strategies that can be used to ensure the credibility, dependability, confirmability and transferability of a study. There is increasing recognition of the valuable contribution qualitative research can make to nursing knowledge. However, it is important that the research is conducted in a rigorous manner and that this is demonstrated in the final research report. A multiple case study that explored the role of the clinical skills laboratory in preparing students for the real world of practice. Multiple sources of evidence were collected: semi-structured interviews (n=58), non-participant observations at five sites and documentary sources. Strategies to ensure the rigour of this research were prolonged engagement and persistent observation, triangulation, peer debriefing, member checking, audit trail, reflexivity, and thick descriptions. Practical examples of how these strategies can be implemented are provided to guide researchers interested in conducting rigorous case study research. While the flexible nature of qualitative research should be embraced, strategies to ensure rigour must be in place.

Guidelines for Conducting Positivist Case Study Research in Information Systems

Directory of Open Access Journals (Sweden)

Graeme Shanks

2002-11-01

Full Text Available The case study research approach is widely used in a number of different ways within the information systems community. This paper focuses on positivist, deductive case study research in information systems. It provides clear definitions of important concepts in positivist case study research and illustrates these with an example research study. A critical analysis of the conduct and outcomes of two recently published positivist case studies is reported. One is a multiple case study that validated concepts in a framework for viewpoint development in requirements definition. The other is a single case study that examined the role of social enablers in enterprise resource planning systems implementation. A number of guidelines for successfully undertaking positivist case study research are identified including developing a clear understanding of key concepts and assumptions within the positivist paradigm; providing clear and unambiguous definitions of the units and interactions when using any theory; carefully defining the boundary of the theory used in the case study; using hypotheses rather than propositions in the empirical testing of theory; using fuzzy or probabilistic propositions in recognising that reality can never be perfectly known; selecting case studies carefully, particularly single case studies; and recognising that generalisation from positivist, single case studies is inherently different from generalisation from single experiments. When properly undertaken, positivist, deductive case study research is a valuable research approach for information systems researchers, particularly when used within pluralist research programs that use a number of different research approaches from different paradigms.

An alternative approach for socio-hydrology: case study research

Science.gov (United States)

Mostert, Erik

2018-01-01

Currently the most popular approach in socio hydrology is to develop coupled human-water models. This article proposes an alternative approach, qualitative case study research, involving a systematic review of (1) the human activities affecting the hydrology in the case, (2) the main human actors, and (3) the main factors influencing the actors and their activities. Moreover, this article presents a case study of the Dommel Basin in Belgium and the Netherlands, and compares this with a coupled model of the Kissimmee Basin in Florida. In both basins a pendulum swing from water resources development and control to protection and restoration can be observed. The Dommel case study moreover points to the importance of institutional and financial arrangements, community values, and broader social, economic, and technical developments. These factors are missing from the Kissimmee model. Generally, case studies can result in a more complete understanding of individual cases than coupled models, and if the cases are selected carefully and compared with previous studies, it is possible to generalize on the basis of them. Case studies also offer more levers for management and facilitate interdisciplinary cooperation. Coupled models, on the other hand, can be used to generate possible explanations of past developments and quantitative scenarios for future developments. The article concludes that, given the limited attention they currently get and their potential benefits, case studies deserve more attention in socio-hydrology.

A case study of a Cuban government institution

International Nuclear Information System (INIS)

Nunez, A.L.; Vazquez, A.; Cruz Cabrera, L.

2004-01-01

The aim of this contribution is to present a case study on the partial implementation of a knowledge management system in an institution. In this case the knowledge management has been directed toward the best performance of the organization. The tool used in case study can be implemented at any institution, including institutions of nuclear or radiological profiles. (author)

The Analysis of a Murder, a Case Study

Science.gov (United States)

Dinan, Frank J.; Szczepankiewicz, Steven H.; Carnaham, Melinda; Colvin, Michael T.

2007-01-01

The analysis of a Murder case study can be used in general chemistry or nonscience major chemistry courses to teach data handling and analysis in a non-laboratory context. This case study will help students to respond more enthusiastically and with more interest to a set of material placed before them related to a real case rather than…

Using Interpretive Qualitative Case Studies for Exploratory Research in Doctoral Studies: A Case of Information Systems Research in Small and Medium Enterprises

Directory of Open Access Journals (Sweden)

Shana R. Ponelis

2015-12-01

Full Text Available The use of the case study method has gained mainstream acceptance in both entrepreneurship and information systems research to develop conceptual and theoretical models that are novel, yet grounded in the literature. In spite of many texts on the case study method and the growing acceptance and use of thereof, there are relatively few examples that discuss how to apply the case study method. The purpose of this paper is to provide such an example by drawing upon the author’s research for her doctoral dissertation in the discipline of information systems and entrepreneurship research. First, the use of qualitative case studies as research method is motivated, then the importance of the research paradigm is discussed and the interpretivist research paradigm justified followed by a detailed discussion of the research design. The paper concludes with a discussion of lessons learned and recommendations based on the author’s experience with using the case study method. The practical yet theoretically founded approach of this paper may be useful to doctoral students who are considering or using the case study method. Equally, supervisors and others involved in research training may find this paper useful as an illustrative example of the case study method for their students.

Facilitating Case Studies in Massage Therapy Clinical Education

Science.gov (United States)

Baskwill, Amanda

2013-01-01

The integration of evidence into reflective health care practice has been on the rise in recent years and is a phenomenon that has affected all health care professions, including massage therapy. Clinical case studies are a research design that follows one patient or subject, making the studies ideal for use in clinical practice. They are valuable for communicating information from clinical practice to the broader community. Case studies have face validity that may be more valuable to individual practitioners than homogeneous randomized controlled trials, as the practitioner may recognize a complex patient in the case report. At Humber College, Student Massage Therapists (SMTs) create, conduct, and communicate results of a clinical case study prior to graduation. This article describes the process and experience. PMID:23730397

A Comparative Comment on the Case Studies

DEFF Research Database (Denmark)

Kjeldsen, Christian Christrup; Ley, Thomas; Jensen, Niels Rosendal

2012-01-01

Denne konklusion sammenfatter hovedtrækkene af de gennemførte case studies i WorkAble-projektet. Vigtige pointer er, at unge på tværs af de forskellige case studies har vanskeligt ved at blive hørt og taget alvorligt. I stedet spises de af med "realistisk vejledning" eller dårlige uddannelses- og...

Logistics case study based research: Towards higher quality

DEFF Research Database (Denmark)

Pedrosa, Alex; Näslund, Dag; Jasmand, Claudia

2012-01-01

analysis of 134 case study based articles published in six leading logistics and supply chain management (SCM) journals between 1998 and 2010 is used to assess and evaluate the quality of the case study based research approach as documented in these publications. Findings – This research provides...... to address to ensure high quality of the case study based research approach in published articles. Research limitations/implications – This study is limited to the analysis of published articles in six logistics and SCM journals. Further research should investigate different journals in logistics and other...

Clean Cities Case Study: Barwood Cab Fleet Study Summary

International Nuclear Information System (INIS)

Whalen, P.

1999-01-01

Barwood Cab Fleet Study Summary is the second in a new series called''Alternative Fuel Information Case Studies,'' designed to present real-world experiences with alternative fuels to fleet managers and other industry stakeholders

Enhancing Systems Engineering Education Through Case Study Writing

Science.gov (United States)

Stevens, Jennifer Stenger

2016-01-01

Developing and refining methods for teaching systems engineering is part of Systems Engineering grand challenges and agenda for research in the SE research community. Retention of systems engineering knowledge is a growing concern in the United States as the baby boom generation continues to retire and the faster pace of technology development does not allow for younger generations to gain experiential knowledge through years of practice. Government agencies, including the National Aeronautics and Space Administration (NASA), develop their own curricula and SE leadership development programs to "grow their own" systems engineers. Marshall Space Flight Center (MSFC) conducts its own Center-focused Marshall Systems Engineering Leadership Development Program (MSELDP), a competitive program consisting of coursework, a guest lecture series, and a rotational assignment into an unfamiliar organization engaged in systems engineering. Independently, MSFC developed two courses to address knowledge retention and sharing concerns: Real World Marshall Mission Success course and its Case Study Writers Workshop and Writers Experience. Teaching case study writing and leading students through a hands-on experience at writing a case study on an SE topic can enhance SE training and has the potential to accelerate the transfer of experiential knowledge. This paper is an overview of the pilot experiences with teaching case study writing, its application in case study-based learning, and identifies potential areas of research and application for case study writing in systems engineering education.

Microbial community adaptation influences long-chain fatty acid conversion during anaerobic codigestion of fats, oils, and grease with municipal sludge.

Science.gov (United States)

Ziels, Ryan M; Karlsson, Anna; Beck, David A C; Ejlertsson, Jörgen; Yekta, Sepehr Shakeri; Bjorn, Annika; Stensel, H David; Svensson, Bo H

2016-10-15

Codigesting fats, oils, and greases with municipal wastewater sludge can greatly improve biomethane recovery at wastewater treatment facilities. Process loading rates of fats, oils, and greases have been previously tested with little knowledge of the digester microbial community structure, and high transient fat loadings have led to long chain fatty acid (LCFA) accumulation and digester upsets. This study utilized recently-developed quantitative PCR assays for syntrophic LCFA-degrading bacteria along with 16S amplicon sequencing to relate changes in microbial community structure to LCFA accumulation during transient loading increases to an anaerobic codigester receiving waste restaurant oil and municipal wastewater sludge. The 16S rRNA gene concentration of the syntrophic β-oxidizing genus Syntrophomonas increased to ∼15% of the Bacteria community in the codigester, but stayed below 3% in the control digester that was fed only wastewater sludge. Methanosaeta and Methanospirillum were the dominant methanogenic genera enriched in the codigester, and together comprised over 80% of the Archaea community by the end of the experimental period. Constrained ordination showed that changes in the codigester Bacteria and Archaea community structures were related to measures of digester performance. Notably, the effluent LCFA concentration in the codigester was positively correlated to the specific loading rate of waste oil normalized to the Syntrophomonas 16S rRNA concentration. Specific loading rates of 0-1.5 × 10(-12) g VS oil/16S gene copies-day resulted in LCFA concentrations below 30 mg/g TS, whereas LCFA accumulated up to 104 mg/g TS at higher transient loading rates. Based on the community-dependent loading limitations found, enhanced biomethane production from high loadings of fats, oils and greases can be achieved by promoting a higher biomass of slow-growing syntrophic consortia, such as with longer digester solids retention times. This work also

Case-Control Studies - An Efficient Observational Study Design

NARCIS (Netherlands)

van Stralen, Karlijn J.; Dekker, Friedo W.; Zoccali, Carmine; Jager, Kitty J.

2010-01-01

Case-control studies are an efficient research method for investigating risk factors of a disease. The method involves the comparison of the odds of exposure in a patient group with that of the odds of exposure in a control group. As only a minority of the population is included in the study, less

Improvement of Students’ Ability to Analyzing Cases on Case Studies Through Journal and Learning Log

Directory of Open Access Journals (Sweden)

Riska Ahmad

2017-08-01

Full Text Available The purpose of this research is to improve the ability of students in guidance and counseling  to  analyzing the case through journals and learning logs This research is classroom action research consists of two cycles. The research phase consisted of planning, implementation, observation and reflection. The research subject are students in guidance and counseling while they are in sixth semester, totaling 20 people who were taking courses in Case Study. The research instrument is the observation guidelines, assessment rubrics and documentation of case studies in the form of journals and learning logs, and case study reports. The study was conducted collaboratively with student magister’s program guidance and counseling. The results showed that in cycle 1 students are able to identify cases, to develop ideas about the case, select and use instruments to analyze the cause of the problem. The results of the research cycle 2, showed 17 of the 20 students were able to analyze the cause of the problem, select the type of service and provide appropriate assistance in accordance with problem cases. Overall value obtained by the students in the subject of Case Studies also increased. In terms of the ability of explanation of the concept, the concept of truth and creativity, based on the ratings given by fellow students of average ability students were in either category, although there is less good, as are associated with the activity of the opinion and the quality of the opinions expressed.

Using Online Case Studies to Enhance Teacher Preparation

Science.gov (United States)

Richman, Laila

2015-01-01

The purpose of this study was to assess the impact interactive, online case studies have on learning for preservice teachers. More specifically, it evaluated whether the use of online case studies in instruction could enhance the level of knowledge the preservice teacher gained from the content material. This study utilized a nonequivalent group,…

Case studies in intelligent computing achievements and trends

CERN Document Server

Issac, Biju

2014-01-01

Although the field of intelligent systems has grown rapidly in recent years, there has been a need for a book that supplies a timely and accessible understanding of this important technology. Filling this need, Case Studies in Intelligent Computing: Achievements and Trends provides an up-to-date introduction to intelligent systems.This edited book captures the state of the art in intelligent computing research through case studies that examine recent developments, developmental tools, programming, and approaches related to artificial intelligence (AI). The case studies illustrate successful ma

Cases for the Net Generation: An Empirical Examination of Students' Attitude toward Multimedia Case Studies

Science.gov (United States)

Sheppard, Michael; Vibert, Conor

2016-01-01

Case studies have been an important tool in business, legal, and medical education for generations of students. Traditional text-based cases tend to be self-contained and structured in such a way as to teach a particular concept. The multimedia cases introduced in this study feature unscripted web-hosted video interviews with business owners and…

Acoustical case studies of three green buildings

Science.gov (United States)

Siebein, Gary; Lilkendey, Robert; Skorski, Stephen

2005-04-01

Case studies of 3 green buildings with LEED certifications that required extensive acoustical retrofit work to become satisfactory work environments for their intended user groups will be used to define areas where green building design concepts and acoustical design concepts require reconciliation. Case study 1 is an office and conference center for a city environmental education agency. Large open spaces intended to collect daylight through clerestory windows provided large, reverberant volumes with few acoustic finishes that rendered them unsuitable as open office space and a conference room/auditorium. Case Study 2 describes one of the first gold LEED buildings in the southeast whose primary design concepts were so narrowly focused on thermal and lighting issues that they often worked directly against basic acoustical requirements resulting in sound levels of NC 50-55 in classrooms and faculty offices, crosstalk between classrooms and poor room acoustics. Case study 3 is an environmental education and conference center with open public areas, very high ceilings, and all reflective surfaces made from wood and other environmentally friendly materials that result in excessive loudness when the building is used by the numbers of people which it was intended to serve.

Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

Science.gov (United States)

Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

2014-08-15

Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Cerebral gliosarcoma: clinico-pathologic study of 8 cases].

Science.gov (United States)

Ayadi, Lobna; Charfi, Slim; Khabir, Abdemajid; Kalle, Rim; Sellami, Ahmed; Makni, Saloua; Boudawara, Zaher; Sellami-Boudawara, Tahya

2010-03-01

Gliosarcomas are biphasic neoplasms composed of a glioblastoma admixed to a sarcomatous component with different lines of differentiation. Histogenesis of these tumors is still discussed. Our objective is to specify clinical and pathological characteristics of this rare neoplasm and to discuss its histogenesis. Retrospective study of eight cases of gliosarcomas diagnosed between January 1998 and December 2004. Clinical, radiological, therapeutic and follow-up data were reviewed. Histological features and immunohistochemical results were also included in this review. Five patients were male, three women with a median age of 50.7 (range 31-74 years). Symptoms were dominated by intracranial hypertension and paralysis. The most common location was parietal or temporo-parietal (5 cases: 62.5%). Pathological exam including histochemical and immunohistochemical study confirmed the diagnosis of gliosarcoma in all cases. Sarcomatous component had features of fibrosarcoma in 5 cases, osteosarcoma in 2 cases and malignant fibrous histiocytoma in 1 case. All patients were treated by surgical excision (complete in five cases and partial in three cases). Adjuvant radiotherapy was received in three cases. One patient was lost on follow-up. Two patients died from postoperative. complications and the five remaining patients died with a medium follow up of 9 months (extremes: 2-24 months). Clinical, radiological and follow-up features of gliosarcomas share great similarities with glioblastomas. Histopathological, histochemical and immunohistochemical studies are helpful in accuracy diagnosis. Recent cytogenetic and molecular data support a monoclonal origin for these tumors.

Qualitative case study methodology in nursing research: an integrative review.

Science.gov (United States)

Anthony, Susan; Jack, Susan

2009-06-01

This paper is a report of an integrative review conducted to critically analyse the contemporary use of qualitative case study methodology in nursing research. Increasing complexity in health care and increasing use of case study in nursing research support the need for current examination of this methodology. In 2007, a search for case study research (published 2005-2007) indexed in the CINAHL, MEDLINE, EMBASE, PsychINFO, Sociological Abstracts and SCOPUS databases was conducted. A sample of 42 case study research papers met the inclusion criteria. Whittemore and Knafl's integrative review method guided the analysis. Confusion exists about the name, nature and use of case study. This methodology, including terminology and concepts, is often invisible in qualitative study titles and abstracts. Case study is an exclusive methodology and an adjunct to exploring particular aspects of phenomena under investigation in larger or mixed-methods studies. A high quality of case study exists in nursing research. Judicious selection and diligent application of literature review methods promote the development of nursing science. Case study is becoming entrenched in the nursing research lexicon as a well-accepted methodology for studying phenomena in health and social care, and its growing use warrants continued appraisal to promote nursing knowledge development. Attention to all case study elements, process and publication is important in promoting authenticity, methodological quality and visibility.

Case Study Research in Software Engineering Guidelines and Examples

CERN Document Server

Runeson, Per; Rainer, Austen; Regnell, Bjorn

2012-01-01

Based on their own experiences of in-depth case studies of software projects in international corporations, in this book the authors present detailed practical guidelines on the preparation, conduct, design and reporting of case studies of software engineering.  This is the first software engineering specific book on the case study research method.

Industrial process heat case studies. [PROSYS/ECONMAT code

Energy Technology Data Exchange (ETDEWEB)

Hooker, D.W.; May, E.K.; West, R.E.

1980-05-01

Commercially available solar collectors have the potential to provide a large fraction of the energy consumed for industrial process heat (IPH). Detailed case studies of individual industrial plants are required in order to make an accurate assessment of the technical and economic feasibility of applications. This report documents the results of seven such case studies. The objectives of the case study program are to determine the near-term feasibility of solar IPH in selected industries, identify energy conservation measures, identify conditions of IPH systems that affect solar applications, test SERI's IPH analysis software (PROSYS/ECONOMAT), disseminate information to the industrial community, and provide inputs to the SERI research program. The detailed results from the case studies are presented. Although few near-term, economical solar applications were found, the conditions that would enhance the opportunities for solar IPH applications are identified.

Repurposing legacy data innovative case studies

CERN Document Server

Berman, Jules J

2015-01-01

Repurposing Legacy Data: Innovative Case Studies takes a look at how data scientists have re-purposed legacy data, whether their own, or legacy data that has been donated to the public domain. Most of the data stored worldwide is legacy data-data created some time in the past, for a particular purpose, and left in obsolete formats. As with keepsakes in an attic, we retain this information thinking it may have value in the future, though we have no current use for it. The case studies in this book, from such diverse fields as cosmology, quantum physics, high-energy physics, microbiology,

HYDROGEOLOGIC CASE STUDIES (DENVER PRESENTATION)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

HYDROGEOLOGIC CASE STUDIES (CHICAGO, IL)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Hydrogeologic Case Studies (Seattle, WA)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Methodology or method? A critical review of qualitative case study reports

Directory of Open Access Journals (Sweden)

Nerida Hyett

2014-05-01

Full Text Available Despite on-going debate about credibility, and reported limitations in comparison to other approaches, case study is an increasingly popular approach among qualitative researchers. We critically analysed the methodological descriptions of published case studies. Three high-impact qualitative methods journals were searched to locate case studies published in the past 5 years; 34 were selected for analysis. Articles were categorized as health and health services (n=12, social sciences and anthropology (n=7, or methods (n=15 case studies. The articles were reviewed using an adapted version of established criteria to determine whether adequate methodological justification was present, and if study aims, methods, and reported findings were consistent with a qualitative case study approach. Findings were grouped into five themes outlining key methodological issues: case study methodology or method, case of something particular and case selection, contextually bound case study, researcher and case interactions and triangulation, and study design inconsistent with methodology reported. Improved reporting of case studies by qualitative researchers will advance the methodology for the benefit of researchers and practitioners.

Methodology or method? A critical review of qualitative case study reports

Science.gov (United States)

Hyett, Nerida; Kenny, Amanda; Dickson-Swift, Virginia

2014-01-01

Despite on-going debate about credibility, and reported limitations in comparison to other approaches, case study is an increasingly popular approach among qualitative researchers. We critically analysed the methodological descriptions of published case studies. Three high-impact qualitative methods journals were searched to locate case studies published in the past 5 years; 34 were selected for analysis. Articles were categorized as health and health services (n=12), social sciences and anthropology (n=7), or methods (n=15) case studies. The articles were reviewed using an adapted version of established criteria to determine whether adequate methodological justification was present, and if study aims, methods, and reported findings were consistent with a qualitative case study approach. Findings were grouped into five themes outlining key methodological issues: case study methodology or method, case of something particular and case selection, contextually bound case study, researcher and case interactions and triangulation, and study design inconsistent with methodology reported. Improved reporting of case studies by qualitative researchers will advance the methodology for the benefit of researchers and practitioners. PMID:24809980

Case studies of uncommon headaches.

Science.gov (United States)

Evans, Randolph W

2006-05-01

The following interesting and uncommon headache disorders are presented through case studies: exploding head syndrome, hypnic headache, neck-tongue syndrome, "Alice in Wonderland" syndrome, nummular headache, red ear syndrome, burning mouth syndrome, spontaneous intracranial hypotension syndrome, and cardiac cephalalgia.

a case study ondo state

African Journals Online (AJOL)

user

the design of a Government Cloud (G-Cloud) network for Ondo State Government which will ... network for a developing economy; a case study of ... France is one of those countries that favour .... Arequipa city. .... Where region 0 = Akure, 1 =.

Gigantic Suprapubic Lymphedema: A Case Study

Directory of Open Access Journals (Sweden)

Roozbeh Tanhaeivash

2016-08-01

Full Text Available We present the first case study of idiopathic gigantic suprapubic lymphedema and buried penis treated with puboscrotal reconstruction in a patient with initial extreme obesity after an extensive weight reduction (120 kg. Massive localized lymphedema of the suprapubic region should be differentiated from the scrotal type. Severe lymphedema could not resolve on its own and weight reduction does not seem to be helpful in such cases.

Capturing Cultural Glossaries: Case-study II

Directory of Open Access Journals (Sweden)

Matete Madiba

2011-10-01

Full Text Available

ABSTRACT: This case-study attempts to present a brief glossary of Northern Sotho medical terms. It is a follow-up of a similar case-study (Madiba, Mphahlele and Kganyago 2003, which was an attempt to capture and present Northern Sotho cooking terms. Case-study I consists of the names for utensils, ingredients and the processes involved in the preparation of cultural dishes. With both these case-studies, the intention has been to use the opportunities availing themselves for the pres-ervation and valorisation of Northern Sotho, including the extension of its corpora to support national dictionary-making processes. The case-study methodology has been very useful for the purposes of this project and the context within which it was undertaken. It aims to provide a model for the collection and presentation of authentic Northern Sotho terminology which otherwise would hardly have been accessible.

Keywords: CULTURAL GLOSSARY, INDIGENOUS KNOWLEDGE SYSTEMS, CORPUS, OUTCOMES-BASED EDUCATION, ASSESSMENT CRITERIA, TRADITIONAL MEDICAL TERMS, COMMUNICATIVE APPROACH, STRUCTURAL APPROACH, METONYMY, HANDS-ON ACTIVITIES, TASK-BASED LEARNING

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OPSOMMING: Die totstandbrenging van kulturele woordversamelings: Ge-vallestudie II. Hierdie gevallestudie probeer om 'n beperkte woordelys van Noord-Sotho- mediese terme aan te bied. Dit is 'n voortsetting van 'n soortgelyke gevallestudie (Madiba, Mpha-hlele en Kganyago 2003 wat 'n poging was om Noord-Sothokookterme te versamel en aan te bied. Gevallestudie I bestaan uit die name van gereedskap, bestanddele, en die prosesse betrokke by die voorbereiding van kulturele geregte. Met altwee hierdie gevallestudies was die bedoeling om die geleenthede te gebruik wat hulleself aanbied vir die bewaring en bestendiging van Noord-Sotho, insluitende die uitbreiding van sy korpora om die nasionale woordeboeksamestellingsprosesse te ondersteun. Die gevallestudiemetodologie was baie nuttig vir die doeleindes van

Vitiligo: A study of 120 cases

Directory of Open Access Journals (Sweden)

Kar P

2001-11-01

Full Text Available Vitiligo is a common pignientary disorder and of major social and cosmetic concern in India. Purpose of the study was to find out age at onset and sex incidence in vitiligo, role of hereditary factors and associations with other diseases. 120 self reporting vitiligo patients attending out patient department of a service hospital were selected for the study and this data was analysed. In the present series out of 120 cases 62 (51.6% were males and 58(48.35%were females. There was practically no difference in sex incidence. The lowest age of onset was two years and the oldest was 65 years. In the majority of patients,52(43.2%, disease started before twenty years of age.8 (6.6% cases gave definite family history of vitiligo. Exposed areas of the body were commonly affected in majority (66.6% of cases. The legs were commonest site of involvement in 60(50% cases. Circunicript type of vitiligo (46.6% was heading the list. Majority of patients (56.6% had multiple lesions. Diabetes mellitus was found in 2 (2.6% patients. Cause of vitiligo is still idiopathic. Hereditary factors hardly play any role in manifestation of vitiligo

Case Studies Approach in Tourism Destination Branding Research

Directory of Open Access Journals (Sweden)

Adeyinka-Ojo S.F.

2014-01-01

Full Text Available A review of literature indicates that there are different types of qualitative research methods such as action research, content analysis, ethnography, grounded theory, historical analysis, phenomenology and case study. However, which approach is to be used depends on several factors such as the nature and objectives of the research. The aim of this paper is to focus on the research methodology aspects of applying case study as a research approach and its relevance in tourism destination branding research specifically on a single case study (SCS context. There are arguments that the SCS is a weak research strategy. Some of the potentials or shortcomings highlighted in the literature include the primitive nature of SCS, flexibility of sample technique, data collection method and data analysis. Others include lack of rigour, reliability, validity, credibility of findings and generalisation. This paper has adopted content analysis of the literature on tourism destination branding. Findings indicate that the quality of SCS can be verified using specific case study tactics for four design tests such as validity (construct, internal and external; and reliability using the case study protocol. Theoretical implication suggests that SCS is an empirical enquiry use to understand complex phenomena and favoured by practitioners.

GLAMUR case-study report: The comparison of three Dutch pork cases (Tasks 3.5)

NARCIS (Netherlands)

Oostindië, H.A.; Horlings, L.G.; Broekhuizen, van R.E.; Hees, E.

2015-01-01

This report presents the case study results of local-global pork chain performances in The Netherlands. As part of Work Package 3, this case study was carried out in cooperation with our Italian GLAMUR partner. The Dutch pork production sector came up after World War 2 and developed into a highly

Case Study: The Mystery of the Seven Deaths--A Case Study in Cellular Respiration

Science.gov (United States)

Gazdik, Michaela

2014-01-01

Cellular respiration, the central component of cellular metabolism, can be a difficult concept for many students to fully understand. In this interrupted, problem-based case study, students explore the purpose of cellular respiration as they play the role of medical examiner, analyzing autopsy evidence to determine the mysterious cause of death…

The reflexive case study method

DEFF Research Database (Denmark)

Rittenhofer, Iris

2015-01-01

This paper extends the international business research on small to medium-sized enterprises (SME) at the nexus of globalization. Based on a conceptual synthesis across disciplines and theoretical perspectives, it offers management research a reflexive method for case study research of postnational...

Persistent User Bias in Case-Crossover Studies in Pharmacoepidemiology

DEFF Research Database (Denmark)

Hallas, Jesper; Pottegård, Anton; Wang, Shirley

2016-01-01

Studying the effect of chronic medication exposure by means of a case-crossover design may result in an upward-biased odds ratio. In this study, our aim was to assess the occurrence of this bias and to evaluate whether it is remedied by including a control group (the case-time-control design...... for the retinal detachment controls were similar, leading to near-null case-time-control estimates for all 3 medication classes. For wrist fracture and stroke, the odds ratios were higher for cases than for controls, and case-time-control odds ratios were consistently above unity, thus implying significant...... residual bias. In case-crossover studies of medications, contamination by persistent users confers a moderate bias upward, which is partly remedied by using a control group. The optimal strategy for dealing with this problem is currently unknown....

[Localized scleroderma: a retrospective study about 92 cases].

Science.gov (United States)

El Fékih, Nadia; Réjaibi, Iménc; Kamoun, Hajer; Zéglaoui, Faten; Fazaa, Bécima; Kharfi, Monia; Kamoun, Mohamed Ridha

2009-09-01

Sclerodermas are rare affections which can be located or generalized. Localized form is the most frequent. The purpose of this study was to describe epidemiologic, clinics, biological, immunological, therapeutic, evolutionary characteristics of the localized scleroderma through a personal series and the data of the literature. We have performed a retrospective study on all patients followed in the department of dermatology of the Hospital Charles Nicole during 14 years period. Our study was about 92 cases of localized scleroderma (73 were females and 19 males). The mean age was 35 years (between 2 and 72 years). The majority of localised sclerodermas (66.2% of the cases) appeared before 40 years with a maximum of frequency between 10 and 30 years (41.6%). Only 11.9% of the cases were observed before 10 years. They were 51 cases (55%) of morphea, 35 cases (38%) of scleroderma in bands including 32 linear scleroderma and 3 scleroderma en coup de sabre, 5 cases (5.5%) of generalized morphea and 1 case (0.15%) of deep morphea. Average therapeutic was specified among 63 patients (87%), and the evolution could be appreciated among 45 patients. The epidemiologic data observed in our series are comparable with those reported in the literature. Therapeutic difficulties and risks of functional after-effects, particular in scleroderma in bands, remain the principal concern for all the authors.

Covert Conditioning: Case Studies in Self-Management.

Science.gov (United States)

Yager, Geoffrey G.

The self-management of thoughts and mental images was used in a series of empirical case studies to influence behavior changes. The target behaviors in the cases reported were smoking, overeating, fingernail biting, thinking self-depreciative thoughts, and responding assertively. Self-monitoring, covert positive reinforcement, covert…

A Case Study about Communication Strategies

Science.gov (United States)

Lin, Grace Hui Chin

2011-01-01

The primary purpose of this case study was to identify what were Taiwanese University English as a Foreign Language (EFL) learners' perceptions about learning communication strategies. This study collected qualitative data about students' beliefs and attitudes as they learned communication strategies. The research question guiding the study was:…

Case Studies in Modelling, Control in Food Processes.

Science.gov (United States)

Glassey, J; Barone, A; Montague, G A; Sabou, V

This chapter discusses the importance of modelling and control in increasing food process efficiency and ensuring product quality. Various approaches to both modelling and control in food processing are set in the context of the specific challenges in this industrial sector and latest developments in each area are discussed. Three industrial case studies are used to demonstrate the benefits of advanced measurement, modelling and control in food processes. The first case study illustrates the use of knowledge elicitation from expert operators in the process for the manufacture of potato chips (French fries) and the consequent improvements in process control to increase the consistency of the resulting product. The second case study highlights the economic benefits of tighter control of an important process parameter, moisture content, in potato crisp (chips) manufacture. The final case study describes the use of NIR spectroscopy in ensuring effective mixing of dry multicomponent mixtures and pastes. Practical implementation tips and infrastructure requirements are also discussed.

Class 1 devices case studies in medical devices design

CERN Document Server

Ogrodnik, Peter J

2014-01-01

The Case Studies in Medical Devices Design series consists of practical, applied case studies relating to medical device design in industry. These titles complement Ogrodnik's Medical Device Design and will assist engineers with applying the theory in practice. The case studies presented directly relate to Class I, Class IIa, Class IIb and Class III medical devices. Designers and companies who wish to extend their knowledge in a specific discipline related to their respective class of operation will find any or all of these titles a great addition to their library. Class 1 Devices is a companion text to Medical Devices Design: Innovation from Concept to Market. The intention of this book, and its sister books in the series, is to support the concepts presented in Medical Devices Design through case studies. In the context of this book the case studies consider Class I (EU) and 510(k) exempt (FDA) . This book covers classifications, the conceptual and embodiment phase, plus design from idea to PDS. These title...

Case Studies in Sports Nutrition.

Science.gov (United States)

Clark, Nancy

1988-01-01

This article presents case studies of two athletes who wanted to affect a change in their body weight in order to enhance athletic performance. Each athlete's problem and the nutrition approach used to solve it are discussed. Caloric values of fast foods are listed. (JL)

Case-Cohort Studies: Design and Applicability to Hand Surgery.

Science.gov (United States)

Vojvodic, Miliana; Shafarenko, Mark; McCabe, Steven J

2018-04-24

Observational studies are common research strategies in hand surgery. The case-cohort design offers an efficient and resource-friendly method for risk assessment and outcomes analysis. Case-cohorts remain underrepresented in upper extremity research despite several practical and economic advantages over case-control studies. This report outlines the purpose, utility, and structure of the case-cohort design and offers a sample research question to demonstrate its value to risk estimation for adverse surgical outcomes. The application of well-designed case-cohort studies is advocated in an effort to improve the quality and quantity of observational research evidence in hand and upper extremity surgery. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Television Medical Dramas as Case Studies in Biochemistry

Science.gov (United States)

Millard, Julie T.

2009-01-01

Several case studies from popular television medical dramas are described for use in an undergraduate biochemistry course. These cases, which illustrate fundamental principles of biochemistry, are used as the basis for problems that can be discussed further in small groups. Medical cases provide an interesting context for biochemistry with video…

Mining Product Data Models: A Case Study

Directory of Open Access Journals (Sweden)

Cristina-Claudia DOLEAN

2014-01-01

Full Text Available This paper presents two case studies used to prove the validity of some data-flow mining algorithms. We proposed the data-flow mining algorithms because most part of mining algorithms focuses on the control-flow perspective. First case study uses event logs generated by an ERP system (Navision after we set several trackers on the data elements needed in the process analyzed; while the second case study uses the event logs generated by YAWL system. We offered a general solution of data-flow model extraction from different data sources. In order to apply the data-flow mining algorithms the event logs must comply a certain format (using InputOutput extension. But to respect this format, a set of conversion tools is needed. We depicted the conversion tools used and how we got the data-flow models. Moreover, the data-flow model is compared to the control-flow model.

Case studies of non-formal music education

NARCIS (Netherlands)

Kors, Ninja

2005-01-01

Non-formal music education is the field of music education outside the regular school curriculum, and delivered by music teachers / music leaders other than the teacher in the classroom. The main body of this research consists of case studies in the Netherlands. In addition there is a number of case

Shea case study Burkina Faso

NARCIS (Netherlands)

S. Drost (Sarah); J.C.A.C. van Wijk (Jeroen); S.R. Vellema (Sietze)

2012-01-01

textabstractThis shea case study is part of a larger Partnerships Resource Centre (PrC) project elaborated in tandem with two Dutch non-governmental organisations (NGOs); ICCO and Oxfam Novib. The endeavour of this ‘action research’ project is to combine the expert knowledge of development

Qualitative case study data analysis: an example from practice.

Science.gov (United States)

Houghton, Catherine; Murphy, Kathy; Shaw, David; Casey, Dympna

2015-05-01

To illustrate an approach to data analysis in qualitative case study methodology. There is often little detail in case study research about how data were analysed. However, it is important that comprehensive analysis procedures are used because there are often large sets of data from multiple sources of evidence. Furthermore, the ability to describe in detail how the analysis was conducted ensures rigour in reporting qualitative research. The research example used is a multiple case study that explored the role of the clinical skills laboratory in preparing students for the real world of practice. Data analysis was conducted using a framework guided by the four stages of analysis outlined by Morse ( 1994 ): comprehending, synthesising, theorising and recontextualising. The specific strategies for analysis in these stages centred on the work of Miles and Huberman ( 1994 ), which has been successfully used in case study research. The data were managed using NVivo software. Literature examining qualitative data analysis was reviewed and strategies illustrated by the case study example provided. Discussion Each stage of the analysis framework is described with illustration from the research example for the purpose of highlighting the benefits of a systematic approach to handling large data sets from multiple sources. By providing an example of how each stage of the analysis was conducted, it is hoped that researchers will be able to consider the benefits of such an approach to their own case study analysis. This paper illustrates specific strategies that can be employed when conducting data analysis in case study research and other qualitative research designs.

Case Studies - Cervical Cancer

Centers for Disease Control (CDC) Podcasts

2010-10-15

Dr. Alan Waxman, a professor of obstetrics and gynecology at the University of New Mexico and chair of the American College of Obstetricians and Gynecologists (ACOG) committee for the underserved, talks about several case studies for cervical cancer screening and management.  Created: 10/15/2010 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), Division of Cancer Prevention and Control (DCPC).   Date Released: 6/9/2010.

Communicative Case Studies for EFL--Lessons for Interactivity.

Science.gov (United States)

Witte, Anne E.

1999-01-01

Discusses use of case studies and role play throughout the curriculum at the Ecole de Hautes Etudes Commerciales du Nord, a French graduate school associated with the Catholic University of Lille. Provides a case study that was developed to reconcile conflicting needs in the business English classroom at the graduate level. Students require…

The Woodworker's Website: A Project Management Case Study

Science.gov (United States)

Jance, Marsha

2014-01-01

A case study that focuses on building a website for a woodworking business is discussed. Project management and linear programming techniques can be used to determine the time required to complete the website project discussed in the case. This case can be assigned to students in an undergraduate or graduate decision modeling or management science…

Case Study: A Separation of Powers Lesson.

Science.gov (United States)

Jenkins, Steve

1986-01-01

Presents a case study involving students in the issue of separation of powers as applied to the 1952 Immigration and Nationality Act. Students examine the case of Jagdish Rai Chadha, an immigrant threatened with deportation whose problems resulted in 1983 U.S. Supreme Court decision declaring legislative veto provision of Immigration and…

Epidemiological follow-up study of Japanese Thorotrast cases

International Nuclear Information System (INIS)

Mori, T.; Maruyama, T.; Kato, Y.; Takahashi, S.

1979-01-01

The authors conducted a follow-up study on 243 Thorotrast-administered war-wounded ex-servicemen in 1975, after a lapse of 30 to 38 years from Thorotrast injections, and found 18 cases of malignant hepatic tumor, 15 cases of other malignant tumors, 2 cases of blood diseases, and 9 cases of liver cirrhosis in 224 cases who had been given Thorotrast intravascularly. The incidence of hepatic and other malignant tumors, blood diseases, and liver cirrhosis was significantly higher than in the controls. The total number of deaths in the Thorotrast-administered cases was also significantly higher than in the controls. In the remaining 19 cases who had been given Thorotrast by a route other than intravascularly, no fatal case related to Thorotrast administration was discovered. In the living cases, however, one sarcoma was observed to have developed at the site of the Thorotrast injection

Shuttle Transportation System Case-Study Development

Science.gov (United States)

Ransom, Khadijah

2012-01-01

A case-study collection was developed for NASA's Space Shuttle Program. Using lessons learned and documented by NASA KSC engineers, analysts, and contractors, decades of information related to processing and launching the Space Shuttle was gathered into a single database. The goal was to provide educators with an alternative means to teach real-world engineering processes and to enhance critical thinking, decision making, and problem solving skills. Suggested formats were created to assist both external educators and internal NASA employees to develop and contribute their own case-study reports to share with other educators and students. Via group project, class discussion, or open-ended research format, students will be introduced to the unique decision making process related to Shuttle missions and development. Teaching notes, images, and related documents will be made accessible to the public for presentation of Space Shuttle reports. Lessons investigated included the engine cutoff (ECO) sensor anomaly which occurred during mission STS-114. Students will be presented with general mission infom1ation as well as an explanation of ECO sensors. The project will conclude with the design of a website that allows for distribution of information to the public as well as case-study report submissions from other educators online.

An ethical analysis of a home visit case study.

Science.gov (United States)

Pibernat, Artur Dalfó; Vidal, Jessica Rosell; Pibernat, Enric Dalfó; Rodríguez, Francisco Javier Pelegrina; Colomer, Gerard; Cid, Maria Feijoo

2017-12-01

This article will explore a clinical case study of a home visit carried out by the case manager nurse. In this case, we will discuss the dilemma of finding the balance between autonomy and beneficence from the perspective of principlist ethics, virtue ethics and the 'ethics of care'. The main conflict in this case study deals with all proposals are unsuitable and it is not necessary for a nurse to pay him a home visit, whereas for the healthcare system it is considered necessary. We could conclude that, during the home visit, the case manager aspires to achieve excellence, and throughout his clinical relationship with Francesc, searches for a series of virtues, respecting certain fundamental principles. In this way, the case managers ensure that Jaume's care is more humanised. The case has been anonymised and confidentiality maintained.

Geothermal Exploration Case Studies on OpenEI (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Young, K.; Bennett, M.; Atkins, D.

2014-03-01

The U.S. Geological Survey (USGS) resource assessment (Williams et al., 2008) outlined a mean 30 GWe of undiscovered hydrothermal resource in the western United States. One goal of the U.S. Department of Energy's (DOE) Geothermal Technology Office (GTO) is to accelerate the development of this undiscovered resource. DOE has focused efforts on helping industry identify hidden geothermal resources to increase geothermal capacity in the near term. Increased exploration activity will produce more prospects, more discoveries, and more readily developable resources. Detailed exploration case studies akin to those found in oil and gas (e.g. Beaumont and Foster, 1990-1992) will give developers central location for information gives models for identifying new geothermal areas, and guide efficient exploration and development of these areas. To support this effort, the National Renewable Energy Laboratory (NREL) has been working with GTO to develop a template for geothermal case studies on the Geothermal Gateway on OpenEI. In 2012, the template was developed and tested with two case studies: Raft River Geothermal Area (http://en.openei.org/wiki/Raft_River_Geothermal_Area) and Coso Geothermal Area (http://en.openei.org/wiki/Coso_Geothermal_Area). In 2013, ten additional case studies were completed, and Semantic MediaWiki features were developed to allow for more data and the direct citations of these data. These case studies are now in the process of external peer review. In 2014, NREL is working with universities and industry partners to populate additional case studies on OpenEI. The goal is to provide a large enough data set to start conducting analyses of exploration programs to identify correlations between successful exploration plans for areas with similar geologic occurrence models.

Cryostat design case studies, principles and engineering

CERN Document Server

2016-01-01

This book enables the reader to learn the fundamental and applied aspects of practical cryostat design by examining previous design choices and resulting cryostat performance. Through a series of extended case studies the book presents an overview of existing cryostat design covering a wide range of cryostat types and applications, including the magnet cryostats that comprise the majority of the Large Hadron Collider at CERN, space-borne cryostats containing sensors operating below 1 K, and large cryogenic liquid storage vessels. It starts with an introductory section on the principles of cryostat design including practical data and equations. This section is followed by a series of case studies on existing cryostats, describing the specific requirements of the cryostat, the challenges involved and the design choices made along with the resulting performance of the cryostat. The cryostat examples used in the studies are chosen to cover a broad range of cryostat applications and the authors of each case are ...

STUDY OF 200 CASES OF PLEURAL FLUID

Directory of Open Access Journals (Sweden)

Ramakrishna R

2016-09-01

Full Text Available BACKGROUND We have studied 200 patients of pleural fluid presenting to our tertiary care centre. Presence of cases of pleural fluid is a common presentation both in pulmonary and extrapulmonary diseases. We analysed the patients having both exudates and transudates and studied the results. MATERIALS AND METHODS We selected patients above 20 years of age and classified the patients with pleural fluid as having transudates and exudates. We studied the causes of transudates and exudates. A total of 200 patients are studied in this prospective study. Diagnosis of pleural exudates is made on the basis of Light’s criteria, chest x-ray, pleural fluid analysis, CT scan in selected patients, sputum examination, bronchoscopy and bronchial washings. Moribund and non-cooperative patients and HIV positives were excluded from the study. RESULTS Among the 200 patients, 91% have exudates. 9% have transudates by Light’s criteria. Tuberculosis is the commonest cause of effusions (64.83% followed by malignancy (13.73% and sympneumonic or parapneumonic effusions (9.89%. Pleural effusions occurred predominantly in males. Prevalence of diabetes Mellitus among cases of tuberculous pleural effusions is 13.56%. Tuberculous effusions are predominantly right-sided. CONCLUSION Predominant cases of pleural fluid are exudates. Commonest cause of pleural effusion is Tuberculosis followed by malignancy both pulmonary and extrapulmonary and sym. and parapneumonic effusions. Prevalence of Diabetes among Tuberculous pleural effusion cases is more or less same as in general population. Cough, expectoration fever, chest pain and breathlessness are the common symptoms occurring in three fourths of the patients of tuberculous pleural effusion. Most of the cases of Tuberculous effusion are above 30 years of age. In the diagnosis of tuberculous pleural effusion, Pleural fluid ADA is very important. Pleural fluid cytology, pleural biopsy, bronchoscopy, bronchial washings and sputum

Hanging an Airplane: A Case Study in Static Equilibrium

Science.gov (United States)

Katz, Debora M.

2009-11-01

Our classrooms are filled with engineering majors who take a semester-long course in static equilibrium. Many students find this class too challenging and drop their engineering major. In our introductory physics class, we often breeze through static equilibrium; to physicists equilibrium is just a special case of Newton's second law. While it is difficult to find more time in the syllabus for any one topic, a hands-on case study may help students to develop their physical intuition about static equilibrium and may help them to succeed in their subsequent classes. This article describes a hands-on case study that you may wish to use in your classroom. (You may also wish to check a case study involving a boat published in this journal in the 1990s. ) The hands-on case study presented here can be easily modified to work at the high school or introductory college level. There are three major components: I) planning, II) doing, and III) calculating.

Case Studies in the Field of Marketing Education: Learner Impact, Case Performance, and Cost Efficiency

Science.gov (United States)

Spais, George S.

2005-01-01

The major objective of this study is to identify a methodology that will help educators in marketing to efficiently manage the design, impact, and cost of case studies. It is my intention is to examine the impact of case study characteristics in relation to the degree of learner involvement in the learning process. The author proposes that…

Putting Words in Their Mouth: Writing Dialogue for Case Studies

Science.gov (United States)

Herreid, Clyde Freeman

2018-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This issue discusses dialogue writing guidelines most relevant to case writing.

Dataset for case studies of hydropower unit commitment

Directory of Open Access Journals (Sweden)

Jinwen Wang

2018-06-01

Full Text Available This paper presents the data all needed for nine case studies of hydropower unit commitment, which determines the optimal operating zones and generating discharges of units after the quarter-hourly releases and water heads are derived by the operation of cascaded hydropower reservoirs. The power output function and feasible operating zones of units are provided, and optimization solvers are used to acquire the results in detail for the case studies, including the quarter-hourly generating discharges, power generations, as well as operating zones of individual units. Performance indices, including the spillage, energy production, and the low-efficiency generating rate, are summarized for all case studies and can be readily used for comparison between algorithms in future.

THE STATE OF THE COMMONS: CASE STUDIES 2010

Directory of Open Access Journals (Sweden)

Rachel Cobcroft

2010-01-01

Full Text Available Abstract: ‘What artists need to see before they can feel confident about the licenses are examples of other[s] taking the licenses; incorporating them into their practices.’ – OpenBusiness.cc, p. 8 The Creative Commons Case Studies initiative, established in 2008, offers the ‘free culture’community a qualitative resource to chronicle trends in open content licensing (OCL. Seeking feedback as to individual and organisational motivations towards OCL adoption, and through its provision of usage data, jurisdiction and disciplinary distribution, the CC Case Studies wiki complements current quantitative research projects such as CC Monitor. Containing over 200 entries in July 2010, the CC Case Studies wiki covers several genres such as publishing, moving images, music, visual arts, interactive resources including games, performance, education, and ‘government 2.0’ open data initiatives. Entries represent 25 contributing jurisdictions, with studies being written in several languages including English, Spanish, Portuguese, German, and Korean. By sharing stories of success and identifying areas of innovation and collaboration, the CC Case Studies wiki encourages creators to contribute to the Commons, whilst contributing to a broader understanding of the dynamics of ‘free culture.’

Collaborative Assessment: Middle School Case Study

Science.gov (United States)

Parkison, Paul T.

2014-01-01

Utilizing a participant observer research model, a case study of the efficacy of a collaborative assessment methodology within a middle school social studies class was conducted. A review of existing research revealed that students' perceptions of assessment, evaluation, and accountability influence their intrinsic motivation to learn. A…

Souvenirs: A Case Study for the 90s.

Science.gov (United States)

Shagam, Janet Yagoda; Decker, Janet; Stanley, Ethel

The case-based study, which presents students with a dilemma that encourages exploration, is becoming a popular method for teaching biology. This Web-based report offers one such case study that asks readers to solve problems and make decisions based on information gathered as they engage with characters or situations in the story. The basis for…

Employing Two Factor Authentication Mechanisms: A Case Study

Science.gov (United States)

Lawrence, Cameron; Fulton, Eric; Evans, Gerald; Firth, David

2014-01-01

This case study examines the life of a digital native who has her online accounts hacked, passwords reset, and is locked out of important online resources including her university email account and Facebook. Part one of the case study examines how the hack was perpetrated and the fallout of losing control of one's digital identity. Part two of the…

SARS: a comparative study on the chest radiography of the mortal cases and the cured cases

International Nuclear Information System (INIS)

Jiang Songfeng; Liu Jingxin; Chen Bihua; Zhang Lieguang; Yin Chibiao; Zhang Fuchun

2003-01-01

Objective: This study is mainly on the radiological findings of the mortal cases of SARS. Methods: The chest X-ray (CXR) findings of 11 mortal cases of SARS were retrospectively studied, and compared with those of the 249 cured cases. Results: The major CXR findings of the mortal cases were: patchy shadows in 10 cases out of 11 (90.90%), frosted glass like change of the lung fields in 9 (81.82%), diffuse lesions in 11 (100%), and involvement of the bilateral lung. There was a statistical difference between the mortal cases and the cured cases on the following 4 manifestations: large shadows, extensive consolidation, frosted glass like change of the lung fields, and diffuse lesions (P<0.01). Conclusion: Large shadows, extensive consolidation, frosted glass like change of the lung fields, diffuse lesions and the bilateral involvement of the lung are the main CXR findings of the mortal cases of SARS. And extensive consolidation and diffuse involvement are strongly indicative. In most of the mortal cases, the latest CXR demonstrated widespread frosted glass like appearance in the lung fields with air bronchogram

Prader-Willi Disease: A Case Study.

Science.gov (United States)

Forbus, William R., III

A case study focuses on the characteristics and physical management of a 15-year-old with Prader-Willi Syndrome, a birth defect associated with hypotonia, insatiable appetite, hypogonadism, central nervous system dysfunction, and abnormal growth and development . A literature review addresses studies dealing with behavior modification of obesity…

Censored Hurdle Negative Binomial Regression (Case Study: Neonatorum Tetanus Case in Indonesia)

Science.gov (United States)

Yuli Rusdiana, Riza; Zain, Ismaini; Wulan Purnami, Santi

2017-06-01

Hurdle negative binomial model regression is a method that can be used for discreate dependent variable, excess zero and under- and overdispersion. It uses two parts approach. The first part estimates zero elements from dependent variable is zero hurdle model and the second part estimates not zero elements (non-negative integer) from dependent variable is called truncated negative binomial models. The discrete dependent variable in such cases is censored for some values. The type of censor that will be studied in this research is right censored. This study aims to obtain the parameter estimator hurdle negative binomial regression for right censored dependent variable. In the assessment of parameter estimation methods used Maximum Likelihood Estimator (MLE). Hurdle negative binomial model regression for right censored dependent variable is applied on the number of neonatorum tetanus cases in Indonesia. The type data is count data which contains zero values in some observations and other variety value. This study also aims to obtain the parameter estimator and test statistic censored hurdle negative binomial model. Based on the regression results, the factors that influence neonatorum tetanus case in Indonesia is the percentage of baby health care coverage and neonatal visits.

Synthesis across social innovation case studies

DEFF Research Database (Denmark)

Jørgensen, Michael Søgaard; Avelino, Flor; Dorland, Jens

2016-01-01

Part 1 is an overview and a comparative analysis of the findings from the 20 case study reports in TRANSIT about aspects of transformative social innovation (TSI). Each of the 20 reports, which the report is based on, includes an analysis of a transnational social innovation network and at least...... two local social innovation initiatives. Part 2 consists of extended abstracts of 8 papers which either focus on empirical phenomena surfacing in different TRANSIT cases (e.g. alternative economic arrangements), take a societal or methodological issue as starting point (e.g. inclusivity or research...... relations), address propositions from TRANSIT proto-theory (institutionalization dialectics, responses to crisis), build upon thematic clusters used for case selection (e.g. spaces for/of innovation, inclusive society, new economy, transformative science) or inductively develop specific sensitizing concepts...

Thermophilic Anaerobic Degradation of Butyrate by a Butyrate-Utilizing Bacterium in Coculture and Triculture with Methanogenic Bacteria

OpenAIRE

Ahring, Birgitte K.; Westermann, Peter

1987-01-01

We studied syntrophic butyrate degradation in thermophilic mixed cultures containing a butyrate-degrading bacterium isolated in coculture with Methanobacterium thermoautotrophicum or in triculture with M. thermoautotrophicum and the TAM organism, a thermophilic acetate-utilizing methanogenic bacterium. Butyrate was β-oxidized to acetate with protons as the electron acceptors. Acetate was used concurrently with its production in the triculture. We found a higher butyrate degradation rate in th...

The Use of Case Studies in OR Teaching

Science.gov (United States)

Penn, Marion L.; Currie, Christine S. M.; Hoad, Kathryn A.; O'Brien, Frances A.

2016-01-01

This article investigates the current use of case studies in the teaching of Operational Research (OR) in the UK: how and where they are used; how they are developed; and whether there is an interest in training this area. It is aimed at lecturers teaching OR who are using or planning to use case studies in their teaching. It may also be of…

Case Studies in Library Computer Systems.

Science.gov (United States)

Palmer, Richard Phillips

Twenty descriptive case studies of computer applications in a variety of libraries are presented in this book. Computerized circulation, serial and acquisition systems in public, high school, college, university and business libraries are included. Each of the studies discusses: 1) the environment in which the system operates, 2) the objectives of…

Guidelines for Using Case Studies in the Teaching-Learning Process

Science.gov (United States)

McFarlane, Donovan A.

2015-01-01

In this paper, the author expresses concerns regarding the extensive use of case studies in the college classroom and advises college and university faculties to be more careful in their selection and use of case studies as an effective­-based method of teaching. The author communicates the important role that case studies play in teaching and…

Homocyst(e)ine and cardiovascular disease: a systematic review of the evidence with special emphasis on case-control studies and nested case-control studies.

Science.gov (United States)

Ford, Earl S; Smith, S Jay; Stroup, Donna F; Steinberg, Karen K; Mueller, Patricia W; Thacker, Stephen B

2002-02-01

Elevated concentrations of homocyst(e)ine are thought to increase the risk of vascular diseases including coronary heart disease and cerebrovascular disease. We searched MEDLINE (1966-1999), EMBASE (1974-1999), SciSearch (1974- 1999), and Dissertation Abstracts (1999) for articles and theses about homocyst(e)ine concentration and coronary heart disease and cerebrovascular disease. We included 57 publications (3 cohort studies, 12 nested case-control studies, 42 case-control studies) that reported results on 5518 people with coronary heart disease (11,068 control subjects) and 1817 people with cerebrovascular disease (4787 control subjects) in our analysis. For coronary heart disease, the summary odds ratios (OR) for a 5-micromol/l increase in homocyst(e)ine concentration were 1.06 (95% CI : 0.99-1.13) for 2 publications of cohort studies, 1.23 (95% CI : 1.07-1.41) for 10 publications of nested case-control studies, and 1.70 (95% CI : 1.50-1.93) for 26 publications of case-control studies. For cerebrovascular disease, the summary OR for a 5-micromol/l increase in homocyst(e)ine concentration were 1.10 (95% CI : 0.94-1.28) for 2 publications of cohort studies, 1.58 (95% CI : 1.35-1.85) for 5 publications of nested case-control studies, and 2.16 (95% CI : 1.65-2.82) for 17 publications of case-control studies. Prospective studies offer weaker support than case-control studies for an association between homocyst(e)ine concentration and cardiovascular disease. Although other lines of evidence support a role for homocyst(e)ine in the pathogenesis of cardiovascular disease, more information from prospective epidemiological studies or clinical trials is needed to clarify this role.

DEVELOPMENT OF CROSS-BORDER AREAS. STUDY CASES REVIEW

Directory of Open Access Journals (Sweden)

Marcela\tȘLUSARCIUC

2015-06-01

Full Text Available The paper aims to review study cases found in the scientific literature concerning the development of cross- border areas in European Union and its neighbourhood. The introductory part of the paper is drawing few considerations about the cross-border areas. Further we identified in the specific literature relevant study cases that provide lessons learned, tools and models that can contribute to the development of the cross-border areas. The last part of the paper is focusing on an inquiry about how this lessons, learned, tools and models may be adapted in case of cross-border areas along the Romanian border with the EU Eastern Neighbourhood.

A Review of Case-Based Learning Practices in an Online MBA Program: A Program-Level Case Study

Science.gov (United States)

Lee, Seung-hee; Lee, Jieun; Liu, Xiaojing; Bonk, Curt J.; Magjuka, Richard J.

2009-01-01

This study examines how a case-based learning approach was used and facilitated in online business education. Perceptions of students and instructors regarding the practices of case-based learning in online environments are explored in terms of instructional design, facilitation, and technology support. This study finds case-based learning to be a…

Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction.

Science.gov (United States)

Scheller, Silvan; Yu, Hang; Chadwick, Grayson L; McGlynn, Shawn E; Orphan, Victoria J

2016-02-12

The oxidation of methane with sulfate is an important microbial metabolism in the global carbon cycle. In marine methane seeps, this process is mediated by consortia of anaerobic methanotrophic archaea (ANME) that live in syntrophy with sulfate-reducing bacteria (SRB). The underlying interdependencies within this uncultured symbiotic partnership are poorly understood. We used a combination of rate measurements and single-cell stable isotope probing to demonstrate that ANME in deep-sea sediments can be catabolically and anabolically decoupled from their syntrophic SRB partners using soluble artificial oxidants. The ANME still sustain high rates of methane oxidation in the absence of sulfate as the terminal oxidant, lending support to the hypothesis that interspecies extracellular electron transfer is the syntrophic mechanism for the anaerobic oxidation of methane. Copyright © 2016, American Association for the Advancement of Science.

Leading and leadership: Reflections on a case study.

OpenAIRE

Joyce, Pauline

2010-01-01

Aim: The aim of this case study was to explore if observing leaders in the context of their day-to-day work can provide an insight into how they lead in particular circumstances. Background: The study was carried out in small organisation which was set up five years ago. Methods: A case study methodology was used. Data was collected by field notes of non-participant and participant observations. Follow-up interviews were transcribed and analysed to contextualise the observations. A refl...

Matched case-control studies: a review of reported statistical methodology

Directory of Open Access Journals (Sweden)

Niven DJ

2012-04-01

Full Text Available Daniel J Niven1, Luc R Berthiaume2, Gordon H Fick1, Kevin B Laupland11Department of Critical Care Medicine, Peter Lougheed Centre, Calgary, 2Department of Community Health Sciences, University of Calgary, Calgary, Alberta, CanadaBackground: Case-control studies are a common and efficient means of studying rare diseases or illnesses with long latency periods. Matching of cases and controls is frequently employed to control the effects of known potential confounding variables. The analysis of matched data requires specific statistical methods.Methods: The objective of this study was to determine the proportion of published, peer reviewed matched case-control studies that used statistical methods appropriate for matched data. Using a comprehensive set of search criteria we identified 37 matched case-control studies for detailed analysis.Results: Among these 37 articles, only 16 studies were analyzed with proper statistical techniques (43%. Studies that were properly analyzed were more likely to have included case patients with cancer and cardiovascular disease compared to those that did not use proper statistics (10/16 or 63%, versus 5/21 or 24%, P = 0.02. They were also more likely to have matched multiple controls for each case (14/16 or 88%, versus 13/21 or 62%, P = 0.08. In addition, studies with properly analyzed data were more likely to have been published in a journal with an impact factor listed in the top 100 according to the Journal Citation Reports index (12/16 or 69%, versus 1/21 or 5%, P ≤ 0.0001.Conclusion: The findings of this study raise concern that the majority of matched case-control studies report results that are derived from improper statistical analyses. This may lead to errors in estimating the relationship between a disease and exposure, as well as the incorrect adaptation of emerging medical literature.Keywords: case-control, matched, dependent data, statistics

CULTURAL CHANGE IN TELECOMMUNICATIONS COMPANIES: A CASE STUDY

Directory of Open Access Journals (Sweden)

Cristiane Alves Anacleto

2014-09-01

Full Text Available This work aims to propose a model for the conduct of cultural change in the IT department of a company in the telecommunications industry. To achieve the goal proposed exploratory, technical procedures used were the case study and literature review. The techniques of data collection in the case study were: participant observation, unstructured interview and document analysis. The proposed model consists of five steps: analysis of the company's strategic planning, cultural diagnosis of the IT department, brainstorming with the staff and managers, compared to the case studies surveyed and proposed actions for the conduct of cultural change. We conclude that a receptive environment, employees not only understand why the changes are necessary, but engage with the process and faithfully executes the steps required, favoring the strategic positioning of the company.

Case studies in organic contaminant hydrogeology

International Nuclear Information System (INIS)

Baker, J.A.

1989-01-01

The effective management of domestic solid waste and hazardous, toxic, and radioactive waste is a major problem in the area of environmental geology and water sciences throughout the world. A series of case studies is presented of organic contaminants from both solid and hazardous waste disposal facilities to provide examples of these problems. The facilities were investigated to determine risks and liabilities before acquisition, to determine the site hydrogeologic conditions for design of appropriate groundwater monitoring plans, and/or to determine the potential for groundwater contamination. The case studies are of disposal facilities located in glacial tills, carbonaceous weathered clay soils, weathered shale, limestone bedrock, dolomite bedrock, and alluvial and sedimentary deposits. The results of these studies and investigations show certain relationships in the distribution of organic pollutants to the different geologic and hydrogeologic characteristics of each facility. In each of the four case studies, all 129 priority pollutants were analyzed in private wells and/or monitoring wells. The 31 volatile organic compounds (VOCs) of the priority pollutant list were the majority of organic compounds detected. When VOCs are found in groundwater impacted by disposal facilities, they are present in groups and tend to be distributed in patterns based on their relative concentrations. It is rare to find only one or two VOCs from facilities where leakage has been detected. The ethylenes and ethanes appear to be more prevalent and mobile than aromatic VOCs. The aromatics are restricted primarily to leachates and wastes and in monitoring wells located adjacent to facilities. 2 refs., 15 figs

Case Study: Student-Produced Videos for the Flipped Classroom

Science.gov (United States)

Prud'homme-Genereux, Annie

2016-01-01

This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes a way of building a library of student-produced videos to use in the flipped classroom.

Nanomaterial Case Studies: Nanoscale Titanium Dioxide (External Review Draft)

Science.gov (United States)

This draft document presents two case studies of nanoscale titanium dioxide (nano-TiO2) used (1) to remove arsenic from drinking water and (2) as an active ingredient in topical sunscreen. The draft case studies are organized around a comprehensive environmental asses...

A Neuroanatomy Teaching Activity Using Case Studies and Collaboration.

Science.gov (United States)

Sheldon, Jane P.

2000-01-01

Describes an activity for use in an introductory psychology course in which students collaborate and apply their neuroanatomy knowledge to three case studies. Provides a table with descriptions of and possible answers for the three case studies and discusses the students' responses. (CMK)

Pilot case-control study of paediatric falls from windows.

Science.gov (United States)

Johnston, Brian D; Quistberg, D Alexander; Shandro, Jamie R; Partridge, Rebecca L; Song, Hyun Rae; Ebel, Beth E

2011-12-01

Unintentional falls from windows are an important cause of paediatric morbidity. There have been no controlled studies to identify modifiable environmental risk factors for window falls in young children. The authors have piloted a case-control study to test procedures for case identification, subject enrolment, and environmental data collection. Case windows were identified when a child 0-9 years old presented for care after a fall from that window. Control windows were identified (1) from the child's home and (2) from the home of an age- and gender-matched child seeking care for an injury diagnosis not related to a window fall. Study staff visited enrolled homes to collect window measurements and conduct window screen performance tests. The authors enrolled and collected data on 18 case windows, 18 in-home controls, and 14 matched community controls. Six potential community controls were contacted for every one enrolled. Families who completed the home visit viewed study procedures positively. Case windows were more likely than community controls to be horizontal sliders (100% vs 50%), to have deeper sills (6.28 vs 4.31 inches), to be higher above the exterior surface (183 vs 82 inches), and to have screens that failed below a threshold derived from the static pressure of a 3-year-old leaning against the mesh (60.0% vs 16.7%). Case windows varied very little from in-home controls. Case-control methodology can be used to study risk factors for paediatric falls from windows. Recruitment of community controls is challenging but essential, because in-home controls tend to be over-matched on important variables. A home visit allows direct measurement of window type, height, sill depth, and screen performance. These variables should all be investigated in subsequent, larger studies covering major housing markets.

Transformational change in healthcare: an examination of four case studies.

Science.gov (United States)

Charlesworth, Kate; Jamieson, Maggie; Davey, Rachel; Butler, Colin D

2016-04-01

Objectives Healthcare leaders around the world are calling for radical, transformational change of our health and care systems. This will be a difficult and complex task. In this article, we examine case studies in which transformational change has been achieved, and seek to learn from these experiences. Methods We used the case study method to investigate examples of transformational change in healthcare. The case studies were identified from preliminary doctoral research into the transition towards future sustainable health and social care systems. Evidence was collected from multiple sources, key features of each case study were displayed in a matrix and thematic analysis was conducted. The results are presented in narrative form. Results Four case studies were selected: two from the US, one from Australia and one from the UK. The notable features are discussed for each case study. There were many common factors: a well communicated vision, innovative redesign, extensive consultation and engagement with staff and patients, performance management, automated information management and high-quality leadership. Conclusions Although there were some notable differences between the case studies, overall the characteristics of success were similar and collectively provide a blueprint for transformational change in healthcare. What is known about the topic? Healthcare leaders around the world are calling for radical redesign of our systems in order to meet the challenges of modern society. What does this paper add? There are some remarkable examples of transformational change in healthcare. The key factors in success are similar across the case studies. What are the implications for practitioners? Collectively, these key factors can guide future attempts at transformational change in healthcare.

Supply chain strategy: empirical case study in Europe and Asia:

OpenAIRE

Sillanpää, Ilkka; Sillanpää, Sebastian

2014-01-01

The purpose of this case study research is to present a literature review of supply chain strategy approaches, develop supply chain strategy framework and to validate a framework in empirical case study. Literature review and case study research are the research methods for this research. This study presents the supply chain strategy framework which merges together business environment, corporate strategy, supply chain demand and supply chain strategy. Research argues that all the different c...

CASE STUDY

African Journals Online (AJOL)

2010-09-01

Sep 1, 2010 ... of the two diseases surgery can be successful, recovery can be similar to that .... lymphocytes predominated in 68% of cases, and that there was an .... using ferritin is the fact that it acts as an acute-phase reactant and will be ...

EL PROGRAMA CASE STUDY HOUSE: INDUSTRIA, PROPAGANDA Y VIVIENDA / Case Study House Program: industry, propaganda and housing

Directory of Open Access Journals (Sweden)

Daniel Díez Martínez

2012-05-01

Full Text Available RESUMEN En enero de 1945, John Entenza, editor de la revista californiana Arts & Architecture, puso en marcha el programa Case Study House, un ambicioso proyecto cuyo firme objetivo era investigar las posibilidades y soluciones del problema de la vivienda al que se enfrentaba los Estados Unidos de la posguerra. Para ello, Entenza diseñó una novedosa estrategia de colaboración entre algunos de los mejores arquitectos californianos del momento y la maquinaria industrial estadounidense, abierta a un proceso de reconversión de producción bélica a objetos para la población civil que tendría lugar en un tiempo récord. Así, el artículo propone el análisis de esa relación entre empresa y domesticidad, entre viabilidad económica y calidad arquitectónica, entre procesos de prefabricación y espíritu individual. Todos ellos conceptos aparentemente opuestos pero que, de la mano del programa Case Study House, lograron un entendimiento que a día de hoy sigue resultando extraordinario. SUMMARY In January 1945, John Entenza, editor of the California Arts & Architecture magazine, launched the ‘Case Study House Program’, an ambitious project whose firm objective was to investigate the possibilities and solutions for the housing problem facing the United States after the war. To do this, Entenza designed a novel strategy for collaboration between some of the best Californian architects of the time and the U.S. industrial machine, open to a process of conversion from military production to objects for the civilian population that would take place in record time. Thus, the article proposes the analysis of the relationship between business and domesticity, between economic viability and architectural quality, between prefabrication processes and individual spirit. All of these seemingly opposing concepts reached, at the hands of the ‘Case Study House Program’, an understanding that still seems extraordinary today.

Association Between Anemia and Cerebral Venous Thrombosis: Case-Control Study

NARCIS (Netherlands)

Coutinho, Jonathan M.; Zuurbier, Susanna M.; Gaartman, Aafke E.; Dikstaal, Arienne A.; Stam, Jan; Middeldorp, Saskia; Cannegieter, Suzanne C.

2015-01-01

Anemia is often considered to be a risk factor for cerebral venous thrombosis (CVT), but this assumption is mostly based on case reports. We investigated the association between anemia and CVT in a controlled study. Unmatched case-control study: cases were adult patients with CVT included in a

Using the Case Study Method in Teaching College Physics

Science.gov (United States)

Burko, Lior M.

2016-10-01

The case study teaching method has a long history (starting at least with Socrates) and wide current use in business schools, medical schools, law schools, and a variety of other disciplines. However, relatively little use is made of it in the physical sciences, specifically in physics or astronomy. The case study method should be considered by physics faculty as part of the effort to transition the teaching of college physics from the traditional frontal-lecture format to other formats that enhance active student participation. In this paper we endeavor to interest physics instructors in the case study method, and hope that it would also serve as a call for more instructors to produce cases that they use in their own classes and that can also be adopted by other instructors.

Case study on bio-remediation. Bio remediation no case study

Energy Technology Data Exchange (ETDEWEB)

Cioffi, J; Lehmicke, L

1993-08-01

This paper introduces two cases of contamination removal using microorganisms in areas contaminated by harmful substances, carried out by ECOVA Inc. in the U.S.A. One case is a removal of soils over an area of 230,000 m[sup 3] contaminated with petroleum-based substances. The removal was intended to reduce contamination at higher than 15,000 ppm down to 1,000 ppm. Discussions on pilot soils and monitoring of activities of living organisms were carried out to determine an optimal condition. It was found that microorganisms having orange color matters have decomposing capability, produce mucopolysaccharides in long-chained hydrocarbon, and make hydrocarbon soluble. The contaminant removal in this area took 19 months. The decomposition work required consideration on temperatures, moistures, aeration frequencies, and nutrient amounts as the affecting factors. The other case is an experiment on removing perchloroethylene (PCE) and trichloroethylene (TCE) from water in the Savanna River. Microorganisms that decompose only TCE were used, with existing methane as a carbon source. An interim result has been obtained that TCE:PCE changed from 0.65:1 to 0.35:1 in twelve months. There has been neither increase nor decrease in the amount of microorganisms.

Effect of methanogenic substrates on anaerobic oxidation of methane and sulfate reduction by an anaerobic methanotrophic enrichment.

KAUST Repository

Meulepas, Roel J W; Jagersma, Christian G; Khadem, Ahmad F; Stams, Alfons J M; Lens, Piet N L

2010-01-01

Anaerobic oxidation of methane (AOM) coupled to sulfate reduction (SR) is assumed to be a syntrophic process, in which methanotrophic archaea produce an interspecies electron carrier (IEC), which is subsequently utilized by sulfate-reducing bacteria

Insider Threat Case Studies at Radiological and Nuclear Facilities

Energy Technology Data Exchange (ETDEWEB)

Pope, Noah Gale [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hobbs, Christopher [Centre for Science and Security Studies, London (United Kingdom)

2015-04-13

Seven case studies are presented. The cases include thefts of various materials and sabotage. For each case there is an overview of the incident, a timeline, a profile of the perpetrator, and a discussion of the security system failures which allowed the incident to take place.

Insider Threat Case Studies at Radiological and Nuclear Facilities

International Nuclear Information System (INIS)

Pope, Noah Gale; Hobbs, Christopher

2015-01-01

Seven case studies are presented. The cases include thefts of various materials and sabotage. For each case there is an overview of the incident, a timeline, a profile of the perpetrator, and a discussion of the security system failures which allowed the incident to take place.

Clinical Study on Five Cases of Carpal tunnel syndrome

Directory of Open Access Journals (Sweden)

Kim Il Hwan

2001-12-01

Full Text Available Objections : The purpose of the study was to evaluate the effectiveness of treating the carpal tunnel syndrome by using both the Herbal Acupuncture and herbal medicine therapy on five cases. Methods : For the Herbal Acupuncture, Jungseonguhhyl No. 1 and Hwanglyunhaedoktang were used. For the herbal medicine, Dangguihwalhyul-tang was used. The patients were treated once in every two days; the result was evaluated after ten treatments. Patients' conditions were monitored through their testimony, phalen's test, nerve conduction study and electromyography. Results : In all five cases, the patients showed improvement; in four cases, the patients no longer had most of the clinical symptoms. Based on the result of the nerve conduction study, for the four cases in which the patients no longer displayed most of the clinical symptoms, their nerve conduction rate improved; for the remaining one case, the patient's nerve conduction rate deteriorated. Conclusions : The results of this study demonstrate that combining the Herbal Acupuncture and herbal medicine therapy can have noticeable effects in treating the carpal tunnel syndrome; developing more variety of the herbal acupuncture would lead to even better treatment results.

Neonatal appendicitis: a survival case study

Directory of Open Access Journals (Sweden)

Izabela Linha Secco

Full Text Available ABSTRACT Objective: To report a case of neonatal appendicitis in a children’s hospital in southern Brazil, demonstrating the impact on neonatal survival. Method: Case study with data collection from medical records, approved by the Institution and Ethics Committee for Research with Human Beings. Results: The clinical picture is initially characterized by food intolerance, evolving to hypoactivity, alteration of vital signs and septicemia due to intestinal perforation. Management is exclusively surgical, since no case described in the literature was diagnosed preoperatively and the findings usually point to acute abdomen. Conclusion: A focused clinical surveillance should be established when the infant presents peritoneal irritation. Follow-up of the evolution and the worsening of the symptoms by nurses, as part of the care team in partnership with the medical team, enables an early surgical intervention, thereby avoiding complications such as septicemia and death.

Test Automation Process Improvement A case study of BroadSoft

OpenAIRE

Gummadi, Jalendar

2016-01-01

This master thesis research is about improvement of test automation process at BroadSoft Finland as a case study. Test automation project recently started at BroadSoft but the project is not properly integrated in to existing process. Project is about converting manual test cases to automation test cases. The aim of this thesis is about studying existing BroadSoft test process and studying different test automation frameworks. In this thesis different test automation process are studied ...

Memory and Learning: A Case Study.

Science.gov (United States)

Webster, Raymond E.

1986-01-01

The usefulness of the Learning Efficency Test (LET), an approach to assessing the learning efficiency and short-term memory recall capacity in children, is described via a case study demonstrating the test's use to develop instructional strategies. (CL)

Case Study Research Methodology in Nursing Research.

Science.gov (United States)

Cope, Diane G

2015-11-01

Through data collection methods using a holistic approach that focuses on variables in a natural setting, qualitative research methods seek to understand participants' perceptions and interpretations. Common qualitative research methods include ethnography, phenomenology, grounded theory, and historic research. Another type of methodology that has a similar qualitative approach is case study research, which seeks to understand a phenomenon or case from multiple perspectives within a given real-world context.

Analysis of case studies - mining, milling and discharges

International Nuclear Information System (INIS)

McEwan, A.C.

2000-01-01

This analysis paper reviews case studies on mining and milling and on radioactive discharges. An outline is given of each of the case studies presented from the perspectives of the study background, the criteria followed in remediation, the decision making process, outcomes achieved, and an evaluation in relation to radiological criteria that are recommended internationally. Site remediation after mining and milling operations may be driven more by aesthetic and environmental concerns than radiological criteria, particularly in more populated areas. The cases illustrated that it is highly desirable that stakeholders, including the public, are involved in decision making at an early stage with agreement on remediation outcomes. In particular, the exposure pathways and dose assessment models employed should generally be agreed with or approved by the regulatory authority prior to remediation work. In the case of remediated properties at Grand Junction, Colorado, it appears the cleanup criteria employed were below or consistent with those applicable to practices, although the situation was one of intervention, and this raises a question as to the cost effectiveness of the cleanup. For some remediation projects there are long term ownership issues arising out of the need for extended public or state oversight of engineered structures or active water treatment facilities, but for these cases ownership issues did not arise for purely radiological reasons. (author)

Service-oriented enterprise modelling and analysis: a case study

NARCIS (Netherlands)

Iacob, Maria Eugenia; Jonkers, H.; Lankhorst, M.M.; Steen, M.W.A.

2007-01-01

In order to validate the concepts and techniques for service-oriented enterprise architecture modelling, developed in the ArchiMate project (Lankhorst, et al., 2005), we have conducted a number of case studies. This paper describes one of these case studies, conducted at the Dutch Tax and Customs

Case Study: Nutrition in the ICU and multi-organ failure ...

African Journals Online (AJOL)

The following case study was discussed at the recent SASPEN Congress held at Spier Estate, Stellenbosch, South Africa. The case study was adapted from the original and used with the kind permission of Fresenius Kabi, Germany. Herewith follows a summarised discussion of the case. It is a reflection of the general ...

Navigating political minefields: partnerships in organizational case study research.

Science.gov (United States)

Moll, Sandra

2012-01-01

The purpose of this paper is to examine key challenges associated with conducting politically sensitive research within a workplace setting, and to highlight strategic partnerships that can be developed to address these challenges. The author's research on employee mental health issues within a large healthcare facility serves as the foundation for identification and description of "political minefields" that investigators may encounter when conducting organizational case study research. Key methodological principles from the literature on qualitative case study research will frame discussion of how to understand and address political sensitivities in the research process. The benefits of conducting organizational case study research will be outlined, followed by discussion of methodological challenges that can emerge in negotiating entry, collecting data (gatekeepers, researcher reflexivity, participant authenticity and non-maleficence), and communicating research findings. Courage, collaboration and clear communication with stakeholders at all levels of the organization are critical to the success of workplace based case study research.

case study

African Journals Online (AJOL)

Elton

particularly in patients who commence ART with low CD4 counts and established opportunistic infections. IRIS results from a pathological inflammatory response to pre-existing infective, host or other antigens, alive or dead, causing clinical deterioration in HIV-infected patients after initiating ART.1 A case definition for IRIS ...

Russia Foreign Policy In Latin America - Case Study Of Nicaragua

Science.gov (United States)

2017-05-23

case study of Nicaragua deeper than the previous thesis. It relates a study to the larger, ongoing dialogue in the literature, filling in gaps and...RUSSIA FOREIGN POLICY IN LATIN AMERICA — CASE STUDY OF NICARAGUA A thesis presented to the Faculty of the U.S. Army Command and...countries, in which case further publication or sale of copyrighted images is not permissible. ii REPORT DOCUMENTATION PAGE Form Approved OMB No

Cultural change in telecommunications companies: a case study

OpenAIRE

Anacleto, Cristiane Alves; Irion, Crishna; Paladini, Edson Pacheco

2014-01-01

This work aims to propose a model for the conduct of cultural change in the IT department of a company in the telecommunications industry. To achieve the goal proposed exploratory, technical procedures used were the case study and literature review. The techniques of data collection in the case study were: participant observation, unstructured interview and document analysis. The proposed model consists of five steps: analysis of the company's strategic planning, cultural diagnosis of the IT ...

A Soft Systems Approach Case Study. Faustin Kamuzora Abstrac

African Journals Online (AJOL)

Kamuzora

The paper details a case study conducted in Lushoto District, Tanzania ... area's cultural and natural resources through sustainable tourism. To achieve .... As stated above, the case study used the SSM for solving the problems in ..... Constraints: time, political environment, level of education of FoUS members. ... Road sector.

A parathyroid scintigraphy case study

International Nuclear Information System (INIS)

O'Leary, Desiree

2005-01-01

Background: There has been much debate concerning the most suitable protocol for parathyroid scintigraphy; the merits of various radiopharmaceuticals versus the correct imaging protocol to visualise both ectopic and anatomically placed adenomas against the various equipment choices have been debated. Aim: To demonstrate, through the use of a case study, the necessity of changing imaging protocols for parathyroid scintigraphy where a definitive imaging diagnosis is absent in the face of strong clinical suspicion. Method: Use is made of Tc99mMIBI, full field chest scintigraphy, a clearly defined imaging protocol and SPECT imaging to locate ectopic parathyroid tissue in a female patient with significant symptoms of parathyroid hyperfunction. Results: A single hyperfunctioning adenoma is located in the pre-carinal area of the mediastinum. Using a radioguided surgical technique the hyperfunctioning tissue is excised and confirmed by histopathology. Conclusion: Whilst a dramatic reduction in patient symptoms was not seen immediately in this patient, the symptoms of the illness have been subsiding since January 2003. This case study demonstrates the necessity of changing imaging protocols for parathyroid scintigraphy where a definitive imaging diagnosis is absent in the face of strong clinical suspicion

A Case Study Application Of Time Study Model In Paint ...

African Journals Online (AJOL)

This paper presents a case study in the development and application of a time study model in a paint manufacturing company. The organization specializes in the production of different grades of paint and paint containers. The paint production activities include; weighing of raw materials, drying of raw materials, dissolving ...

Bridging the Performance Gap with Ergonomics: A Case Study

Science.gov (United States)

Rethaber, James D.

2011-01-01

Faced with increased incidences of work-related strain and sprain injuries and OSHA-recordable injuries, the organization in this case study details how it resolved these performance-related issues. This case study also demonstrates the effectiveness of Thomas Gilbert's (1978) Behavior Engineering Model as a tool for analyzing, defining, and…

Stochastic efficiency: five case studies

International Nuclear Information System (INIS)

Proesmans, Karel; Broeck, Christian Van den

2015-01-01

Stochastic efficiency is evaluated in five case studies: driven Brownian motion, effusion with a thermo-chemical and thermo-velocity gradient, a quantum dot and a model for information to work conversion. The salient features of stochastic efficiency, including the maximum of the large deviation function at the reversible efficiency, are reproduced. The approach to and extrapolation into the asymptotic time regime are documented. (paper)

Case Studies Approach in Tourism Destination Branding Research

OpenAIRE

Adeyinka-Ojo S.F.; Nair V.; Khoo-Lattimore C.

2014-01-01

A review of literature indicates that there are different types of qualitative research methods such as action research, content analysis, ethnography, grounded theory, historical analysis, phenomenology and case study. However, which approach is to be used depends on several factors such as the nature and objectives of the research. The aim of this paper is to focus on the research methodology aspects of applying case study as a research approach and its relevance in tourism destination bran...

Regression analysis for secondary response variable in a case-cohort study.

Science.gov (United States)

Pan, Yinghao; Cai, Jianwen; Kim, Sangmi; Zhou, Haibo

2017-12-29

Case-cohort study design has been widely used for its cost-effectiveness. In any real study, there are always other important outcomes of interest beside the failure time that the original case-cohort study is based on. How to utilize the available case-cohort data to study the relationship of a secondary outcome with the primary exposure obtained through the case-cohort study is not well studied. In this article, we propose a non-parametric estimated likelihood approach for analyzing a secondary outcome in a case-cohort study. The estimation is based on maximizing a semiparametric likelihood function that is built jointly on both time-to-failure outcome and the secondary outcome. The proposed estimator is shown to be consistent, efficient, and asymptotically normal. Finite sample performance is evaluated via simulation studies. Data from the Sister Study is analyzed to illustrate our method. © 2017, The International Biometric Society.

Assessment of global phase uncertainty in case-control studies

Directory of Open Access Journals (Sweden)

van Houwelingen Hans C

2009-09-01

Full Text Available Abstract Background In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The measure 1 quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: and based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. Results A new global relative efficiency measure was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Conclusion Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk.

Set anode potentials affect the electron fluxes and microbial community structure in propionate-fed microbial electrolysis cells

KAUST Repository

Rao, Hari Ananda; Katuri, Krishna; Logan, Bruce E.; Saikaly, Pascal

2016-01-01

, but their relative abundance varied among the tested SAPs. Microbial community analysis implies that complete degradation of propionate in all the tested SAPs was facilitated by syntrophic interactions between fermenters and Geobacter at the anode and ferementers

Nuclear Knowledge Management Case Studies Catalogue “NKM CSC”

International Nuclear Information System (INIS)

Atieh, T.

2016-01-01

Full text: Over the past several years, many nuclear organizations in IAEA’s Member States have accumulated considerable experiences and achievements in the development and application of nuclear knowledge management (NKM) methodology and tools to improve their organizational performance. The IAEA NKM Section has initiated a project entitled “NKM Case Studies Catalogue (NKM CSC)” to capture and document, as well as preserve NKM experience and facilitate its sharing among NKM practitioners and experts. This is done through collection and preservation of information of relevant experiential knowledge in “case study” format. The catalogue will therefore support community of practice mechanisms. An input template is currently under development and will be used to help contributors in Member States who are providing concise set of information about their respective case studies. This information will be made searchable and easily retrievable through a platform that supports collaboration among NKM practitioners and experts. It is planned to launch the Nuclear Knowledge Management Case Studies Catalogue “NKM CSC” at the occasion of the “Third International Conference on Nuclear Knowledge Management—Challenges and Approaches, 7-–11 November 2016, Vienna, Austria”, and to include the accepted case studies submitted to this Conference. (author

Clinical and laboratorial study of 19 cases of mucopolysaccharidoses

Directory of Open Access Journals (Sweden)

Albano Lilian M. J.

2000-01-01

Full Text Available The mucopolysaccharidoses (MPS are a heterogeneous group of inborn errors of lysosomal glycosaminoglycan (GAG metabolism. The importance of this group of disorders among the inborn errors of metabolism led us to report 19 cases. METHOD: We performed clinical, radiological, and biochemical evaluations of the suspected patients, which allowed us to establish a definite diagnosis in 19 cases. RESULTS: Not all patients showed increased GAG levels in urine; enzyme assays should be performed in all cases with strong clinical suspicion. The diagnosis was made on average at the age of 48 months, and the 19 MPS cases, after a full clinical, radiological, and biochemical study, were classified as follows: Hurler -- MPS I (1 case; Hunter -- MPS II (2 cases; Sanfilippo -- MPS III (2 cases; Morquio -- MPS IV (4 cases; Maroteaux-Lamy -- MPS VI (9 cases; and Sly -- MPS VII (1 case. DISCUSSION: The high relative frequency of Maroteaux-Lamy disease contrasts with most reports in the literature and could express a population variability.

Real Time Locations Systems or Outsourcing: A Case Study

Science.gov (United States)

Lawrence, Cameron; Firth, David; Khumalo, Floyd

2013-01-01

Information Technology has transformed almost all aspects of modern healthcare and is playing a vital role in the administration of hospitals around the world. This case study examines one hospital's struggle to solve crucial operational problems related to the efficient management of medical equipment inventory. This case study is the result of…

Case Study: Pancreas cancer with Whipple's operation | Blaauw ...

African Journals Online (AJOL)

The following case study was discussed at the SASPEN Workshop held during the Nutrition Congress 2014. It is a reflection of the general opinion of the audience, followed by a rationale of the latest literature on the topic. Herewith follows a summarised discussion of the case. Keywords: pancreas cancer, Whipple ...

Case Study Report about Gender Impact Assessment

DEFF Research Database (Denmark)

Faber, Stine Thidemann; Agustin, Lise Rolandsen

2013-01-01

The aim of this national case study report is to take a closer look at the use of Gender Impact Assessments in Denmark in order to describe the Danish implementation of this specific Gender Mainstreaming method. By way of analyzing two selected cases (two law proposals put forward by The Danish...... Ministry of Employment and the Danish Ministry of Transport, respectively) the aim is to assess the transformative potential of GIA as it is performed in Denmark....

Hamlet's Suicide Soliloquy: A Case Study in Suicide Ideology.

Science.gov (United States)

Jenkins, Andrew P.

This paper presents a secondary-level teaching technique that can be used in an integrated English and health education curriculum. The exercise provides students and teachers with a case study of a suicidal person for the purpose of teaching the warning signs of suicide, appropriate questioning, and referral skills. The case study uses Hamlet's…

CASE STUDIES OF USE OF DESIGN OF EXPERIMENTS IN MATERIAL RESEARCH

Directory of Open Access Journals (Sweden)

Salil Kumar Roy

2003-01-01

Full Text Available The paper describes principles of factorial and fractional factorial design of experiments. The various ways of analysing data obtained by these procedures are shown via four case studies. Yates method was followed in case 1 where the effect of anode type, carbon content of steel, temperature, and agitation on cathodic protection of steel in seawater, on current density, was studied. In case 2, a glass was formulated within 10 constituante melted, quantity water and tested for flow caracteristics, from the result the factor effect was calculated. In case 3, analysis of results is done in a very simple way. In this case, the effect of carbon content, surface condition, temperature, and agitation on the corrosion of steel in seawater was studied. In case 4, the effect of eleven constituents on acid resistance of a cast iron enamel has been studied through sixteen experimental compositions. This case gives a method to find out which of the sixteen experimental compositions is nearest to a target value.

Sudden Death Following Exercise; a Case Series Study

Directory of Open Access Journals (Sweden)

Fares Najari

2016-04-01

Full Text Available Introduction: Natural and unexpected death that happens within less than one hour of first symptom occurrence is called sudden death. Cardiovascular diseases are the main known reason of sudden death and more than 75% of sudden deaths in athletes are assigned to it. Here we reported the autopsy results of all cases with sudden death following exercise that were referred to forensic center of Tehran, Iran, from 2009 to 2014. Methods: In this cross sectional study all subjects who were registered to forensic medicine center of Tehran, Iran, from 2009 to 2014, as a case of sudden death following exercise were evaluated. Demographic data and medical history as well as autopsy and toxicology findings were retrospectively gathered using profiles of the deceased. Results were reported using descriptive analysis. Results: 14 cases were registered as sudden death following exercise in forensic medicine profiles during the study period. Exploring the files of the mentioned deceased, revealed five non-compatible cases in this regard. Finally, 9 eligible cases were enrolled (88.9% male. The mean age of the deceased was 28.66 ± 10.86 years (range: 7 – 40. Toxicological tests were available for 7 cases, one of which was positive for tramadol. Sudden death following football was reported most frequently (44.4%. Only 3 (33.3% cases had herald signs such as chest pain, syncope, or loss of consciousness. 1 case (11.11% had a positive history of sudden death in relatives. Conclusion: Although most sudden death victims are asymptomatic until the event, all those who suffer from symptoms such as chest pain, shortness of breath, dizziness, fatigue and irregular heart rate during physical activities, should be screened regarding common probable causes of sudden death.

OBSESSIONS: CASE REPORT STUDY

Directory of Open Access Journals (Sweden)

Miloš Židanik

2004-01-01

Full Text Available Background. Obsessions are one of the most refractory psychiatric disorders. The therapeutic guidelines include a psychopharmacotherapy and the use of behavioural and supportive psychotherapy.Methods. This case report study presents a patient with a homicide obsessions at the forefront and narcissistic personality disorder in background. The use of analytical oriented psychotherapy, which helped to resolve axis-1 symptoms, is described.Conclusions. In the therapy of patients it is important to have the knowledge about the national therapeutic guidelines and critical distance toward them as well. Which therapy to use should be decided by the individual patient’s needs.

Developing the DESCARTE Model: The Design of Case Study Research in Health Care.

Science.gov (United States)

Carolan, Clare M; Forbat, Liz; Smith, Annetta

2016-04-01

Case study is a long-established research tradition which predates the recent surge in mixed-methods research. Although a myriad of nuanced definitions of case study exist, seminal case study authors agree that the use of multiple data sources typify this research approach. The expansive case study literature demonstrates a lack of clarity and guidance in designing and reporting this approach to research. Informed by two reviews of the current health care literature, we posit that methodological description in case studies principally focuses on description of case study typology, which impedes the construction of methodologically clear and rigorous case studies. We draw from the case study and mixed-methods literature to develop the DESCARTE model as an innovative approach to the design, conduct, and reporting of case studies in health care. We examine how case study fits within the overall enterprise of qualitatively driven mixed-methods research, and the potential strengths of the model are considered. © The Author(s) 2015.

Employing Case Study Methodology in Special Educational Settings

Science.gov (United States)

Rouse, Angelise M.

2016-01-01

In general, case studies are a preferred strategy when "how" or "why" questions are being posed, when the investigator has little control over events, and when the focus is on a contemporary phenomenon within some real-life context (Yin, 2009). This article will examine the advantages and disadvantages of employing case study…

A clinico-pathological study of 70 cases of pemphigus

Directory of Open Access Journals (Sweden)

Arya S

1999-01-01

Full Text Available A clinicopalhological study of 70 cases of pemphigus observed over a span of four and a half years from January 1992 to June 1996 at the Sir J.J. Group of Hospitals and Grant Medical College, Mumbai is reported. Pemphigus vulgaris constituted the single largest group of 43 cases, followed by pemphigus foliaceus (25 cases and pemphigus vegetans (2 cases. Majority of the cases were seen in the age group of 21-60 years, with a slight male predominance. The youngest patient was 14 years while the eldest was aged 75 years. Mucosal involvement was seen in 31 cases of pemphigus vulgaris, as opposed to only 5 cases of pemphigus foliaceus. Flaccid bullae were present in 100% cases. Pruritus was complained of in 14 cases, though it was more common in pemphigus vegetans and vulgaris. Salient histopathological features of pemphigus vulgaris observed were (I intraepidermal suprabasal blisters (35 cases, (2 presence of acantholytic cells (40 cases, (3 "Row of tombstone appearance" (I8 cases and (4 acantholysis involving follicular sheath (20 cases. Main histopathological features of pemphigus foliaceus were (1 subcorneal blister (15 case, (2 acantholysis (24 cases and (3 bulla cavity containing inflammatory infiltrate (12 cases. Both cases of pemphigus vegetans showed hyperkeratosis, papillomatosis and irregular acanthosis with intra-epidermal eosinophilic abscesses besides suprabasal lacunae.

Population Isolation in the Philippine War: A Case Study

Science.gov (United States)

2015-05-21

Cuba. On January 1902 Bell caught negative press. Written reports were furnished to the senate committee hearings from MAJ Cornelius Gardener , who...25 Robert Ramsey, Savage Wars of Peace: Case Studies of Pacification in the Philippines,1900-1902. OP 24 (Fort Leavenworth, KS: Combat Studies...Institute Press, 2007. 44 ___. Savage Wars of Peace: Case Studies of Pacification in the Philippines,1900-1902. (OP 24) Fort Leavenworth, KS: Combat

Case studies and role play: learning strategies in nursing.

Science.gov (United States)

Cogo, Ana Luísa Petersen; Pai, Daiane Dal; Aliti, Graziella Badin; Hoefel, Heloísa Karnas; Azzolin, Karina de Oliveira; Busin, Lurdes; Unicovsky, Margarita Ana Rubin; Kruse, Maria Henriqueta Luce

2016-01-01

to report professors' experience in a public university of Southern region of Brazil using case studies and role play as learning strategies for nursing care of hospitalized adults. learning experience report from the Nursing Care of Adults I class of nursing undergraduate course. the development of case studies and role play considered health care needs from epidemiological profile of chronic noncommunicable diseases morbidity and mortality, nursing as an assisting method, and social aspects of hospitalized individuals. Role play planning was made by creating a stage in laboratory of practices and dialogues comprising students and professors interaction. case studies and role play encouraged students to active search for learning and brought theory closer to real health care situations.

Case studies: Mining and milling activities - South African facilities

International Nuclear Information System (INIS)

Metcalf, P.E.; Woude, S. van der

2000-01-01

The mining and milling of minerals is a very important industry in South Africa that employs more than 300,000 people. South Africa extracts minerals with naturally occurring radionuclides, amongst which uranium, monazite and zircon. Two case studies involving environmental restoration activities that are typically associated with mining and minerals processing are discussed. The first case study, Katdoringbos, describes the restoration of a contaminated site where scrap material originating from the mining and minerals processing facilities had been recycled. The other case study, Crown 4, deals with the restoration of a contaminated site where a mine tailings dam had been removed and the owner of the land wished to develop it for commercial exploitation. (author)

Case Studies, Ethics, Philosophy and Liberal Learning for the Management Profession

DEFF Research Database (Denmark)

Rendtorff, Jacob Dahl

2015-01-01

Case studies can be an important methodology for ethics and philosophy in humanistic management and liberal education as well as in the social sciences because they integrate a deeper, reflective, philosophical, and ethical understanding of the organization. A case study approach based...... on philosophy of management contributes to putting into practice the Carnegie Foundation report Rethinking Undergraduate Education: Liberal Learning for the Profession. This approach is both inductive and deductive and very different from a soft Socratic approach to case studies such as the one often used...... in business schools following the Harvard method, wherein students are supposed to get knowledge through the reading of a case prepared by the teacher or from a business textbook. The aim of the case study is to analyze a concrete case and get general knowledge through the integrated analysis of the different...

Using the Case Study Method in Teaching College Physics

Science.gov (United States)

Burko, Lior M.

2016-01-01

The case study teaching method has a long history (starting at least with Socrates) and wide current use in business schools, medical schools, law schools, and a variety of other disciplines. However, relatively little use is made of it in the physical sciences, specifically in physics or astronomy. The case study method should be considered by…

Using a Case-Study Article to Effectively Introduce Mitosis

Science.gov (United States)

Van Hoewyk, Doug

2007-01-01

Community college students in a nonmajors biology class are introduced to mitosis by reading a case-study article that allows them to gauge how many times various parts of their bodies have been regenerated. The case-study article allows students to develop a conceptual framework of the cell cycle prior to a lecture on mitosis. (Contains 1 figure.)

Case Study of the NENE Code Project

National Research Council Canada - National Science Library

Kendall, Richard; Post, Douglass; Mark, Andrew

2007-01-01

...) Program is sponsoring a series of case studies to identify the life cycles, workflows, and technical challenges of computational science and engineering code development that are representative...

The case study of biomaterials and biominerals

Science.gov (United States)

Del Hoyo Martínez, Carmen

2013-04-01

The teaching of biomaterials as case study by on-line platform , susceptible to develop both individually and in groups, got different objectives proposed by the European Higher Education System, among which include: participate actively in the teaching-learning process by students, interpreting situations, adapt processes and solutions. It also improves oral and written communication, analytical skills and synthesis and also the ability to think critically. Biomaterials have their origin in biominerals. These are solid inorganic compounds of defined structure, consisting of molecular control mechanisms that operate in biological systems. Its main functions are: structural support, a reservoir of essential elements, sensors, mechanical protection and storage of toxic elements. Following the demand of materials compatible with certain functional systems of our body, developed biomaterials. Always meet the condition of biocompatibility. Should be tolerated by the body and do not provoke rejection. This involves a comprehensive study of physiological conditions and the anatomy of the body where a biomaterial has to be implemented. The possibility of generating new materials from biominerals has a major impact in medicine and other fields could reach as geology, construction, crystallography, etc. While the study of these issues is in its infancy today, can be viewed as an impact on the art and future technology. Planning case study that students would prepare its report for discussion in subgroups. Occurs then the pooling of individual analysis, joint case discussion and adoption by the subgroup of a consensual solution to the problem. The teacher as facilitator and coordinator of the final case analysis, sharing leads to group-wide class and said the unanimous decision reached by the students and gives his opinion on the resolution of the case. REFERENCES D.P. Ausubel. Psicología Educativa. Un punto de vista cognoscitivo. Trillas. Ed. 1983. E.W. Eisner. Procesos

Collegiality in education: a case study

African Journals Online (AJOL)

Erna Kinsey

This case study therefore investigated the effects of a collegial management style on teaching and learning ... resources cannot solely guarantee success at matriculation level. ... vily on school principals, their management teams and the governing .... may be necessary to employ the notion of building with a new member.

Predicting Students Drop Out: A Case Study

Science.gov (United States)

Dekker, Gerben W.; Pechenizkiy, Mykola; Vleeshouwers, Jan M.

2009-01-01

The monitoring and support of university freshmen is considered very important at many educational institutions. In this paper we describe the results of the educational data mining case study aimed at predicting the Electrical Engineering (EE) students drop out after the first semester of their studies or even before they enter the study program…

The Glioma International Case-Control Study

DEFF Research Database (Denmark)

Amirian, E. Susan; Armstrong, Georgina N; Zhou, Renke

2016-01-01

Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly...... describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen...

Management & Communication: Project Management Case Study

CERN Multimedia

Nathalie Dumeaux

2004-01-01

We are pleased to announce the recent launch of a new workshop on Project Management. This is designed for People with budgetary, scheduling and/or organizational responsibilities in a project or a sub-project. The objectives through a management case study specially suited to CERN are: to become familiar with modern management techniques in use for structuring, planning, scheduling, costing and progress monitoring of a project or a sub-project. to understand in-depth issues associated with Deliverable-oriented Project Management, Earned Value Management, Advanced Project Cost Engineering and Project Risk Management. The full description of this workshop can be found here. The next session will be held on 8 October 2004. If you are interested in this workshop, please contact Nathalie Dumeaux, email or 78144. Programme of Seminars October to December 2004 Situation : 21.09.2004 Séminaires bilingues Dates Jours Places disponibles Project Management Case study 8 October 1 oui Intr...

Sacroiliac joint dysfunction: a case study.

Science.gov (United States)

Murray, William

2011-01-01

Pain is a widespread issue in the United States. Nine of 10 Americans regularly suffer from pain, and nearly every person will experience low back pain at one point in their lives. Undertreated or unrelieved pain costs more than $60 billion a year from decreased productivity, lost income, and medical expenses. The ability to diagnose and provide appropriate medical treatment is imperative. This case study examines a 23-year-old Active Duty woman who is preparing to be involuntarily released from military duty for an easily correctable medical condition. She has complained of chronic low back pain that radiates into her hip and down her leg since experiencing a work-related injury. She has been seen by numerous providers for the previous 11 months before being referred to the chronic pain clinic. Upon the first appointment to the chronic pain clinic, she has been diagnosed with sacroiliac joint dysfunction. This case study will demonstrate the importance of a quality lower back pain assessment.

Delivering Online Examinations: A Case Study

Directory of Open Access Journals (Sweden)

John MESSING

2004-07-01

Full Text Available Delivering Online Examinations: A Case Study Jason HOWARTH John MESSING Irfan ALTAS Charles Sturt University Wagga Wagga-AUSTRALIA ABSTRACT This paper represents a brief case study of delivering online examinations to a worldwide audience. These examinations are delivered in partnership with a commercial online testing company as part of the Industry Master’s degree at Charles Sturt University (CSU. The Industry Master’s degree is an academic program for students currently employed in the IT industry. Using Internet Based Testing (IBT, these students are examined in test centres throughout the world. This offers many benefits. For example, students have the freedom of sitting exams at any time during a designated interval. Computer-based testing also provides instructors with valuable feedback through test statistics and student comments. In this paper, we document CSU’s use of the IBT system, including how tests are built and delivered, and how both human and statistical feedback is used to evaluate and enhance the testing process.

STUDY ON MATERNAL MORTALITY AND NEAR MISS CASE

Directory of Open Access Journals (Sweden)

Ritanjali Behera

2017-12-01

Full Text Available BACKGROUND Maternal mortality traditionally has been the indicator of maternal health. More recently the review of cases of near miss obstetric event is found to be useful to investigate maternal mortality. Cases of near miss are those, where a woman nearly died but survived a complication that occur during pregnancy or child birth. Aim and Objective 1. To analyse near miss cases and maternal deaths. 2. To determine maternal near miss indicator and to analyse the cause and contributing factors for both of them. MATERIALS AND METHODS This prospective observational study conducted in M.K.C.G. medical college, Berhampur from 1st October 2015 to 30th September 2017. All the cases of maternal deaths and near miss cases defined by WHO criteria are taken. Information regarding demographic profile and reproductive parameters are collected and results are analysed using percentage and proportion. RESULTS Out of 17977 deliveries 201 were near miss cases and 116 were maternal deaths. MMR was 681, near miss incidence 1.18, maternal death to near miss ratio was 1:1.73. Hypertensive disorder of pregnancy (37.4% was the leading cause followed by haemorrhage (17.4%. For near miss cases 101 cases fulfilled clinical criteria, 61 laboratory criteria and 131 cases management based criteria. CONCLUSION Hypertensive disorder of pregnancy and haemorrhage are the leading cause of maternal death and for near miss cases most common organ system involved was cardiovascular system. All the near miss cases should be interpreted as opportunities to improve the health care services.

Science of the Particular: An Advocacy of Naturalistic Case Study in Health Research

NARCIS (Netherlands)

Abma, T.A.; Stake, R.E.

2014-01-01

Case studies can provide us with in-depth understanding of a single demarcated entity. Cases can be corporations and clinics, but are usually people. There are several approaches to case study. Naturalistic case study constitutes the science of the particular. The aim of naturalistic case study is

Thermodynamic and Kinetic Response of Microbial Reactions to High CO2.

Science.gov (United States)

Jin, Qusheng; Kirk, Matthew F

2016-01-01

Geological carbon sequestration captures CO 2 from industrial sources and stores the CO 2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO 2 concentration. This study uses biogeochemical modeling to explore the influence of CO 2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO 2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO 2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO 2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO 2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses.

Thermodynamic and kinetic response of microbial reactions to high CO2

Directory of Open Access Journals (Sweden)

Qusheng Jin

2016-11-01

Full Text Available Geological carbon sequestration captures CO2 from industrial sources and stores the CO2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO2 concentration. This study uses biogeochemical modeling to explore the influence of CO2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses.

A case study of Impetigo

Directory of Open Access Journals (Sweden)

Mansouri P

1993-05-01

Full Text Available This is a report of a case study on 234 patients with impetigo who referred to Razi Dermatology Hospital from April to November, 1989. Treatment was started immediately after obtaining direct smear and performing culture and antibiotic sensitivity test. The most common organism responsible for impetigo was the coagulase-positive staphylococcus (71%. In 13.7% of the cases, the coagulase-negative staphylococcus was grown on culture media, but none of the cultures showed streptococcus as the main organism. Treatment was started with oral penicillin V, oral erythromycin, benzathine penicillin G injection, oral cephalexin, and topical fuccidin. Clinical and bacteriological evaluation after 3-7 days showed that it is preferable to use oral cephalexin instead of other protocols such as oral erythromycin, which has previously been the drug of choice for impetigo. In addition, topical fuccidin with a 75% curative rate was the first drug for treatment, with the same effect as the oral cephalexin

Mathematical modelling a case studies approach

CERN Document Server

Illner, Reinhard; McCollum, Samantha; Roode, Thea van

2004-01-01

Mathematical modelling is a subject without boundaries. It is the means by which mathematics becomes useful to virtually any subject. Moreover, modelling has been and continues to be a driving force for the development of mathematics itself. This book explains the process of modelling real situations to obtain mathematical problems that can be analyzed, thus solving the original problem. The presentation is in the form of case studies, which are developed much as they would be in true applications. In many cases, an initial model is created, then modified along the way. Some cases are familiar, such as the evaluation of an annuity. Others are unique, such as the fascinating situation in which an engineer, armed only with a slide rule, had 24 hours to compute whether a valve would hold when a temporary rock plug was removed from a water tunnel. Each chapter ends with a set of exercises and some suggestions for class projects. Some projects are extensive, as with the explorations of the predator-prey model; oth...

Case-control vaccine effectiveness studies: Data collection, analysis and reporting results.

Science.gov (United States)

Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

2017-06-05

The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection

Ebstein′s anomaly--an autopsy study of 28 cases.

Directory of Open Access Journals (Sweden)

Madiwale C

1997-01-01

Full Text Available Twenty eight autopsy specimens of Ebstein′s anomaly were studied in order to evaluate the morphologic features of the abnormal tricuspid valve. All cases showed marked dilatation of the original tricuspid annulus, a normally positioned anterior leaflet and variable downward displacement of the posterior and septal leaflets. Sixteen cases showed a very large anterior leaflet. All three leaflets showed dysplastic features and a wide range of anatomic abnormalities in the valve and valve apparatus. A thin walled atrialised right ventricle was present in nine cases. Associated cardiac anomalies were seen in 21 cases, the commonest being an atrial septal defect (17 cases.

Interactive verification of Markov chains: Two distributed protocol case studies

Directory of Open Access Journals (Sweden)

Johannes Hölzl

2012-12-01

Full Text Available Probabilistic model checkers like PRISM only check probabilistic systems of a fixed size. To guarantee the desired properties for an arbitrary size, mathematical analysis is necessary. We show for two case studies how this can be done in the interactive proof assistant Isabelle/HOL. The first case study is a detailed description of how we verified properties of the ZeroConf protocol, a decentral address allocation protocol. The second case study shows the more involved verification of anonymity properties of the Crowds protocol, an anonymizing protocol.

Travel Efficiency Assessment Method: Three Case Studies

Science.gov (United States)

This slide presentation summarizes three case studies EPA conducted in partnership with Boston, Kansas City, and Tucson, to assess the potential benefits of employing travel efficiency strategies in these areas.

A Case Study on Idiopathic Orbital Pseudotumor: Surgery and ...

African Journals Online (AJOL)

This is a case study of five isolated orbital nerve inflammatory pseudotumor cases ... Optic disk edema was observed by ophthalmoscopy. ... The patients on clinical examination were found to have protrusion, reduced visual acuity of the right ...

Identification of novel potential acetate-oxidizing bacteria in an acetate-fed methanogenic chemostat based on DNA stable isotope probing.

Science.gov (United States)

Wang, Hui-Zhong; Gou, Min; Yi, Yue; Xia, Zi-Yuan; Tang, Yue-Qin

2018-05-11

Acetate is a significant intermediate of anaerobic fermentation. There are two pathways for converting acetate to CH 4 and CO 2 : acetoclastic methanogenesis by acetoclastic methanogens, and syntrophic acetate oxidation by acetate-oxidizing bacteria (AOB) and hydrogenotrophic methanogens. Detailed investigations of syntrophic acetate-oxidizing bacteria (SAOB) should contribute to the elucidation of the microbial mechanisms of methanogenesis. In this study, we investigated the major phylogenetic groups of acetate-utilizing bacteria (AUB) in a mesophilic methanogenic chemostat fed with acetate as the sole carbon source by using DNA stable isotope probing (SIP) technology. The results indicated that acetoclastic methanogenesis and acetate oxidization/hydrogenotrophic methanogenesis coexisted in the mesophilic chemostat fed with acetate, operated at a dilution rate of 0.1 d -1 . OTU Ace13(9-17) (KU869530), Ace13(9-4) (KU667241), and Ace13(9-23) (KU667236), assigned to the phyla Firmicutes and Bacteroidetes, were probably potential SAOB in the chemostat, which needs further investigation. Species in the phyla Proteobacteria, Deferribacteres, Acidobacteria, Spirochaetes and Actinobacteria were probably capable of utilizing acetate for their growth. Methanoculleus was likely to be the preferred hydrogenotrophic methanogen for syntrophy with AOB in the chemostat.

Accounting for control mislabeling in case-control biomarker studies.

Science.gov (United States)

Rantalainen, Mattias; Holmes, Chris C

2011-12-02

In biomarker discovery studies, uncertainty associated with case and control labels is often overlooked. By omitting to take into account label uncertainty, model parameters and the predictive risk can become biased, sometimes severely. The most common situation is when the control set contains an unknown number of undiagnosed, or future, cases. This has a marked impact in situations where the model needs to be well-calibrated, e.g., when the prediction performance of a biomarker panel is evaluated. Failing to account for class label uncertainty may lead to underestimation of classification performance and bias in parameter estimates. This can further impact on meta-analysis for combining evidence from multiple studies. Using a simulation study, we outline how conventional statistical models can be modified to address class label uncertainty leading to well-calibrated prediction performance estimates and reduced bias in meta-analysis. We focus on the problem of mislabeled control subjects in case-control studies, i.e., when some of the control subjects are undiagnosed cases, although the procedures we report are generic. The uncertainty in control status is a particular situation common in biomarker discovery studies in the context of genomic and molecular epidemiology, where control subjects are commonly sampled from the general population with an established expected disease incidence rate.

Predicting Protein-Protein Interactions Using BiGGER: Case Studies

Directory of Open Access Journals (Sweden)

Rui M. Almeida

2016-08-01

Full Text Available The importance of understanding interactomes makes preeminent the study of protein interactions and protein complexes. Traditionally, protein interactions have been elucidated by experimental methods or, with lower impact, by simulation with protein docking algorithms. This article describes features and applications of the BiGGER docking algorithm, which stands at the interface of these two approaches. BiGGER is a user-friendly docking algorithm that was specifically designed to incorporate experimental data at different stages of the simulation, to either guide the search for correct structures or help evaluate the results, in order to combine the reliability of hard data with the convenience of simulations. Herein, the applications of BiGGER are described by illustrative applications divided in three Case Studies: (Case Study A in which no specific contact data is available; (Case Study B when different experimental data (e.g., site-directed mutagenesis, properties of the complex, NMR chemical shift perturbation mapping, electron tunneling on one of the partners is available; and (Case Study C when experimental data are available for both interacting surfaces, which are used during the search and/or evaluation stage of the docking. This algorithm has been extensively used, evidencing its usefulness in a wide range of different biological research fields.

NOx trade. Case studies

International Nuclear Information System (INIS)

Jantzen, J.

2002-01-01

Some of the questions with respect to the trade of nitrogen oxides that businesses in the Netherlands have to deal with are dealt with: should a business buy or sell rights for NOx emission; which measures must be taken to reduce NOx emission; how much must be invested; and how to deal with uncertainties with regard to prices. Simulations were carried out with the MOSES model to find the answers to those questions. Results of some case studies are presented, focusing on the chemical sector in the Netherlands. Finally, the financial (dis)advantages of NOx trade and the related uncertainties for a single enterprise are discussed [nl

Effective communication. A Platonic case study

NARCIS (Netherlands)

Wakker, Gerry C.; Wieling, Martijn; Kroon, Martin; Van Noord, Gertjan

As a contribution to the valedictory volume for John Nerbonne I present a case study of two thematically similar passages in Plato where I will make use of an analysis based on discourse cohesion and above all on the rhetorical and manipulative use of particles to show how a single (leading)

A methodological review of qualitative case study methodology in midwifery research.

Science.gov (United States)

Atchan, Marjorie; Davis, Deborah; Foureur, Maralyn

2016-10-01

To explore the use and application of case study research in midwifery. Case study research provides rich data for the analysis of complex issues and interventions in the healthcare disciplines; however, a gap in the midwifery research literature was identified. A methodological review of midwifery case study research using recognized templates, frameworks and reporting guidelines facilitated comprehensive analysis. An electronic database search using the date range January 2005-December 2014: Maternal and Infant Care, CINAHL Plus, Academic Search Complete, Web of Knowledge, SCOPUS, Medline, Health Collection (Informit), Cochrane Library Health Source: Nursing/Academic Edition, Wiley online and ProQuest Central. Narrative evaluation was undertaken. Clearly worded questions reflected the problem and purpose. The application, strengths and limitations of case study methods were identified through a quality appraisal process. The review identified both case study research's applicability to midwifery and its low uptake, especially in clinical studies. Many papers included the necessary criteria to achieve rigour. The included measures of authenticity and methodology were varied. A high standard of authenticity was observed, suggesting authors considered these elements to be routine inclusions. Technical aspects were lacking in many papers, namely a lack of reflexivity and incomplete transparency of processes. This review raises the profile of case study research in midwifery. Midwives will be encouraged to explore if case study research is suitable for their investigation. The raised profile will demonstrate further applicability; encourage support and wider adoption in the midwifery setting. © 2016 John Wiley & Sons Ltd.

Case study of siting technology for underground nuclear power plant

International Nuclear Information System (INIS)

Hibino, Satoshi; Komada, Hiroya; Honsho, Shizumitsu; Fujiwara, Yoshikazu; Motojima, Mutsumi; Nakagawa, Kameichiro; Nosaki, Takashi

1991-01-01

Underground siting method is one of new feasible siting methods for nuclear power plants. This report presents the results on case studies on underground siting. Two sites of a steeply inclined and plateau like configurations were selected. 'Tunnel type cavern; all underground siting' method was applied for the steeply inclined configuration, and 'shaft type semi-cavern; partial underground siting' method was applied for the plateau like configuration. The following designs were carried out for these two sites as case studies; (1) conceptual designs, (2) geological surveys and rock mechanics tests, (3) stability analysis during cavern excavations, (4) seismic stability analysis of caverns during earthquake, (5) reinforcement designs for caverns, (6) drainage designs. The case studies showed that these two cases were fully feasible, and comparison between two cases revealed that the 'shaft type semi-cavern; partial underground siting' method was more suitable for Japanese islands. As a first step of underground siting, therefore, the authors recommend to construct a nuclear power plant by this method. (author)

A Mixed Methods Sampling Methodology for a Multisite Case Study

Science.gov (United States)

Sharp, Julia L.; Mobley, Catherine; Hammond, Cathy; Withington, Cairen; Drew, Sam; Stringfield, Sam; Stipanovic, Natalie

2012-01-01

The flexibility of mixed methods research strategies makes such approaches especially suitable for multisite case studies. Yet the utilization of mixed methods to select sites for these studies is rarely reported. The authors describe their pragmatic mixed methods approach to select a sample for their multisite mixed methods case study of a…

A Framework for Analysis of Case Studies of Reading Lessons

Science.gov (United States)

Carlisle, Joanne F.; Kelcey, Ben; Rosaen, Cheryl; Phelps, Geoffrey; Vereb, Anita

2013-01-01

This paper focuses on the development and study of a framework to provide direction and guidance for practicing teachers in using a web-based case studies program for professional development in early reading; the program is called Case Studies Reading Lessons (CSRL). The framework directs and guides teachers' analysis of reading instruction by…

Fertility Decline in Pakistan 1980-2006 : A Case Study

OpenAIRE

World Bank

2010-01-01

Pakistan was selected as a case study because of its estimated 40 percent decline in fertility between 1980 and 2006. Pakistan's high fertility rate began to decline gradually after the late 1980s and has continued to fall since then, though progress has been uneven and there have been signs of a slowdown in recent years. Unlike the other four case study countries (Algeria, Botswana, Iran,...

Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

DEFF Research Database (Denmark)

Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

2015-01-01

tested in the study; which is contradicting to the general belief that thermophilic methanogens are more vulnerable to high ammonia loads compared to mesophilic. This unexpected finding underlines the fact that the complete knowledge of ammonia inhibition effect on hydrogenotrophic methanogens is still...

SUDDEN NATURAL DEATHS IN MEDICOLEGAL CASES- AN AUTOPSY BASED STUDY

Directory of Open Access Journals (Sweden)

C. S. Sreedevi

2017-01-01

Full Text Available BACKGROUND Death occurring in apparently healthy individual in a case of natural death may arise suspicion of foul play. In these circumstances these cases may be subjected to medicolegal autopsy. The disease condition may be unknown to the individual and the relatives. This study was done to review the exact cause of death in sudden unexpected deaths, and enabling or assisting the legal authorities in detection of crime, to prove or disprove the foul play. Body mass index is the most frequently used indicator of body fatness. An attempt is made to find out whether there is any significant relationship between BMI and the risk for sudden cardiac death. MATERIALS AND METHODS Data of 50 cases of sudden unexpected death brought for medicolegal autopsy at govt. T.D. medical college Alappuzha in the year 2010 were studied and information were collected from the postmortem records. Data was entered in the proforma. The histopathological examination findings of relevant cases were studied. Analysis was done using MS EXCEL and Chi-square test was used as the test of significance in the comparison between two categorical variables. RESULTS In 50 cases, male predominance was observed and 88% were males in which 50% of males died of atherosclerotic occlusive coronary artery disease and among females 33% died of myocardial infarction. While considering the systemic distribution of cause of death, the cardiovascular system was found to be most commonly affected, 33 cases (66% followed by respiratory system 7 cases (14%. In 4 (8% cases gastrointestinal system was affected. In Two cases (4% central nervous system was affected and others were generalized infection, which constituted 2 cases. Out of 33 cases observed in cardiovascular system the commonest cause being the atherosclerotic occlusive coronary artery diseases involving 27 cases (81.81% in which the predominant involvement was seen in left anterior descending artery 21 cases (77.77% followed by right

Nanomaterial Case Study: Nanoscale Silver in Disinfectant Spray (Final Report)

Science.gov (United States)

EPA announced the release of the final report, Nanomaterial Case Study: Nanoscale Silver in Disinfectant Spray. This report represents a case study of engineered nanoscale silver (nano-Ag), focusing on the specific example of nano-Ag as possibly used in disinfectant spr...

Learning Machine Learning: A Case Study

Science.gov (United States)

Lavesson, N.

2010-01-01

This correspondence reports on a case study conducted in the Master's-level Machine Learning (ML) course at Blekinge Institute of Technology, Sweden. The students participated in a self-assessment test and a diagnostic test of prerequisite subjects, and their results on these tests are correlated with their achievement of the course's learning…

The Danish National Case Study Report

DEFF Research Database (Denmark)

Brodersen, Søsser; Jørgensen, Michael Søgaard

the projects so it fits into the university schedule, without leaving out the time perspective of the clients, and secure the research is applicable for the clients and based on their need for knowledge. The case studies have shown different roles of a Science Shop. All Science Shops have a role as mediator...

Teaching Business Intelligence through Case Studies

Science.gov (United States)

Pomykalski, James J.

2015-01-01

In teaching business students about the application and implementation of technology, especially involving business intelligence, it is important to discover that project success in enterprise systems development efforts often depend on the non-technological problems or issues. The focus of this paper will be on the use of multiple case studies in…

It's Not Funny: A Case Study

Science.gov (United States)

Méndez-Morse, Sylvia

2015-01-01

This case study may be used with personnel supervision, school law, and other school leadership courses. It describes the behavior and actions of one teacher toward another. Student discussions can focus on supervision, workplace mobbing, workplace bullying, as well as sexual harassment. Students should focus on a school leader's role in such…

Teaching the Holocaust through Case Study

Science.gov (United States)

Misco, Thomas

2009-01-01

This article responds to the curricular challenges teachers face with Holocaust education, including cursory treatments and a lack of focus on individual experiences. First, the author argues for a case-study approach to help students reengage concrete and complex features of the Holocaust as a point of departure for subsequent inquiry. In…

Case Studies Nested in Fuzzy-Set QCA on Sufficiency: Formalizing Case Selection and Causal Inference

Science.gov (United States)

Schneider, Carsten Q.; Rohlfing, Ingo

2016-01-01

Qualitative Comparative Analysis (QCA) is a method for cross-case analyses that works best when complemented with follow-up case studies focusing on the causal quality of the solution and its constitutive terms, the underlying causal mechanisms, and potentially omitted conditions. The anchorage of QCA in set theory demands criteria for follow-up…

Abstracts of Remediation Case Studies, Volume 9

Science.gov (United States)

This report, published by the Federal Remediation Technologies Roundtable (FRTR), is a collection of recently published abstracts summarizing 13 cost and performance case studies on the use of remediation technologies at contaminated sites.

TA Treatment of Depression - A Hermeneutic Single-Case Efficacy Design Study - ‘Linda’ - a mixed outcome case

Directory of Open Access Journals (Sweden)

Mark Widdowson

2013-07-01

Full Text Available Hermeneutic Single-Case EfficacyDesign (HSCED is a systematic case study research method involving the cross-examination of mixed method data to generate both plausible arguments that the client changed due to therapy and alternative explanations. The present study is the fourth article of a case series which has investigated the process and outcome of transactional analysis psychotherapy using Hermeneutic Single-Case Efficacy Design (Elliott 2002. The client, Linda, was a 45 yearold white British woman with mild depression who attended nine sessions of therapy. The conclusion of the judges was that this was a mixed-outcome case:whilst the client improved over the course of therapy and was positive about her experience of therapy, her changes did not last when she experienced considerable stressful events during follow-up. Linda provided a detailed and idiosyncratic description of the aspects of the therapy which were most helpful for her. A cross-case comparison with other cases in this series suggests several interesting features which are worthy of further investigation. Specifically, the use of a shared theoretical framework and an egalitarian therapeutic relationship were helpful. As with other cases in this series, the client experienced positive changes in her interpersonal relationships suggesting that this outcome of TA therapy warrants further investigation

Case Study: The Hunger Pains--Ghrelin, Weight Loss, and Maintenance

Science.gov (United States)

Diener, Lynn M.

2013-01-01

This article presents a case study regarding healthy weight loss and the role of the hormone ghrelin in maintaining a lower body weight. This study was designed specifically for use in an introductory college-level physiology course. It addresses the use of the case study in teaching digestion and metabolism, exploring the role of hormones in…

Case Study: Pancreas cancer with Whipple's operation

African Journals Online (AJOL)

Keywords: pancreas cancer, Whipple procedure, SASPEN case study ..... Grade A. Grade B. Grade C. Nasogastric tube required. 4-7 days or reinserted > postoperative day 3 .... malabsorption and vitamin and mineral deficiencies are the most.

Review of ORD Nanomaterial Case Studies Workshop

Science.gov (United States)

The following is a letter report from the Executive Committee of the BOSC concerning the review of the ORD Nanomaterial Case Studies Workshop: Developing a Comprehensive Environmental Assessment Research Strategy for Nanoscale Titanium Dioxide.

BTS Case Study: The Galloway Family Home

International Nuclear Information System (INIS)

Brandegee Group

1999-01-01

Case study of an energy-efficient Habitat for Humanity house that uses 30% less energy than conventional residential construction. The project was part of the Jimmy Carter Work Project in rural Appalachia in 1997

How informative are case studies of spider bites in the medical literature?

Science.gov (United States)

Stuber, Marielle; Nentwig, Wolfgang

2016-05-01

We analyzed the reliability and information content of 134 medical case studies on spider bites, published in 91 journal articles. Overall, we found that only 22% of these studies fulfilled the criteria for a verified spider bite. This means that the majority of such case studies cannot be attributed to a given spider species and usually not even to a spider. Their scientific value is negligible, moreover, such publications are even dangerous because they suggest incorrect conclusions. Secondly, we found that such case studies usually do not follow an obvious structure and many details on the development of symptoms, therapy and healing process are widely lacking. So even for verified spider bites, the comparability of case studies is limited. We discuss the obvious failure of a reviewing process for case studies and give recommendations how to increase the currently low information content of medical case studies on spider bites. Copyright © 2016 Elsevier Ltd. All rights reserved.

Business Registration Reform Case Studies : Malaysia

OpenAIRE

Olaisen, John

2009-01-01

This collection of case studies describes experiences and draws lessons from varied business registration reform programs in economies in vastly different stages of development: Bulgaria, Estonia, Ireland, Madagascar, and Malaysia. Over the last twenty years, a number of countries have recognized the importance of smooth and efficient business start up procedures. A functioning business re...

The Case Study as a Method for Exploring Expert Music Teaching

Directory of Open Access Journals (Sweden)

Jane Saunders

2010-05-01

Full Text Available This article explains how the case study method was used in an exploration of the career of an expert music teacher. The contextual and holistic qualities of the case study are discussed. In addition, insider research and the situated knowledge of participants in this case study are considered, leading to a brief summary of the research findings and an explication of the expert music teacher.

Software Engineering Researchers' Attitudes on Case Studies and Experiments: an Exploratory Survey

OpenAIRE

Tofan, Dan; Galster, Matthias; Avgeriou, Paris; Weyns, Danny

2011-01-01

Background: Case studies and experiments are research methods frequently applied in empirical software engineering. Experiments are well-­understood and their value as an empirical method is recognized. On the other hand, there seem to be different opinions on what constitutes a case study, and about the value of case studies as a thorough research method. Aim: We aim at exploring the attitudes of software engineering researchers on case studies and experiments. Furthermore, we investigate ho...

Marketing and clinical trials: a case study.

Science.gov (United States)

Francis, David; Roberts, Ian; Elbourne, Diana R; Shakur, Haleema; Knight, Rosemary C; Garcia, Jo; Snowdon, Claire; Entwistle, Vikki A; McDonald, Alison M; Grant, Adrian M; Campbell, Marion K

2007-11-20

Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, of 12 factors that may affect the success of the marketing and sales activities associated with clinical trials. The case study demonstrates that trials need various categories of people to buy in - hence, to be successful, trialists must embrace marketing strategies to some extent. The performance of future clinical trials could be enhanced if trialists routinely considered these factors.

Institutional total energy case studies

Energy Technology Data Exchange (ETDEWEB)

Wulfinghoff, D.

1979-07-01

Profiles of three total energy systems in institutional settings are provided in this report. The plants are those of Franciscan Hospital, a 384-bed facility in Rock Island, Illinois; Franklin Foundation Hospital, a 100-bed hospital in Franklin, Louisiana; and the North American Air Defense Command Cheyenne Mountain Complex, a military installation near Colorado Springs, Colorado. The case studies include descriptions of plant components and configurations, operation and maintenance procedures, reliability, relationships to public utilities, staffing, economic efficiency, and factors contributing to success.

Epidemiological study of road traffic accident cases in Greater Noida: Hospital Based Study

Directory of Open Access Journals (Sweden)

Rupali Roy

2014-09-01

Full Text Available Introduction: Road accidents are associated with numerous problems each of which needs to be addressed separately [1]. Accidents, therefore, can be studied in terms of agent, host and environmental factors and epidemiologically classified into time, place and person distribution [2]. Objectives: 1.To assess the prevalence of RTAs coming to hospital and 2.To know the epidemiological factors related to RTAs and associated prevalence in hospital based study. Methodology: This cross sectional study was conducted at SMSR, Gr Noida, in 2012. The study group consisted of all the RTA victims reporting to casualty in the last one year. The victims of the accidents were interviewed on a pretested semi structured performa. Results: In that one year period total number of reported accident cases was 144. The age groups of the study subjects were between 13-65 years. Out of total study subjects, only 16 were female. Again out of the total accident cases 45% were attended by police and of all injured, 45.8% were driver by occupation (7% without driving license. Among these drivers, 11% were not attentive during driving because of various reasons. Ambulance services had reached in 46.5% cases. Fracture was the most common type (60% of injury among all types of injuries. Among the applicable population only 33% wore helmet or seat belts. Conclusions: Only half of the total accident cases were attended by police and again only half of them received ambulance services. One third injuries were because of not wearing seat belt and helmets.

Epidemiological study of road traffic accident cases in Greater Noida: Hospital Based Study

Directory of Open Access Journals (Sweden)

Rupali Roy

2014-09-01

Full Text Available Introduction: Road accidents are associated with numerous problems each of which needs to be addressed separately [1]. Accidents, therefore, can be studied in terms of agent, host and environmental factors and epidemiologically classified into time, place and person distribution [2]. Objectives: 1.To assess the prevalence of RTAs coming to hospital and 2.To know the epidemiological factors related to RTAs and associated prevalence in hospital based study. Methodology: This cross sectional study was conducted at SMSR, Gr Noida, in 2012. The study group consisted of all the RTA victims reporting to casualty in the last one year. The victims of the accidents were interviewed on a pretested semi structured performa. Results: In that one year period total number of reported accident cases was 144. The age groups of the study subjects were between 13-65 years. Out of total study subjects, only 16 were female. Again out of the total accident cases 45% were attended by police and of all injured, 45.8% were driver by occupation (7% without driving license. Among these drivers, 11% were not attentive during driving because of various reasons. Ambulance services had reached in 46.5% cases. Fracture was the most common type (60% of injury among all types of injuries. Among the applicable population only 33% wore helmet or seat belts. Conclusions: Only half of the total accident cases were attended by police and again only half of them received ambulance services. One third injuries were because of not wearing seat belt and helmets.

A case-case study of mobile phone use and acoustic neuroma risk in Japan.

Science.gov (United States)

Sato, Yasuto; Akiba, Suminori; Kubo, Osami; Yamaguchi, Naohito

2011-02-01

Results of case-control studies of mobile phone use and acoustic neuroma have been inconsistent. We conducted a case-case study of mobile phone use and acoustic neuroma using a self-administered postal questionnaire. A total of 1589 cases identified in 22 hospitals throughout Japan were invited to participate, and 787 cases (51%) actually participated. Associations between laterality of mobile phone use prior to the reference dates (1 and 5 years before diagnosis) and tumor location were analyzed. The overall risk ratio was 1.08 (95% confidence interval (CI), 0.93-1.28) for regular mobile phone use until 1 year before diagnosis and 1.14 (95% CI, 0.96-1.40) for regular mobile phone use until 5 years before diagnosis. A significantly increased risk was identified for mobile phone use for >20 min/day on average, with risk ratios of 2.74 at 1 year before diagnosis, and 3.08 at 5 years before diagnosis. Cases with ipsilateral combination of tumor location and more frequently used ear were found to have tumors with smaller diameters, suggesting an effect of detection bias. Furthermore, analysis of the distribution of left and right tumors suggested an effect of tumor-side-related recall bias for recall of mobile phone use at 5 years before diagnosis. The increased risk identified for mobile phone users with average call duration >20 min/day should be interpreted with caution, taking into account the possibilities of detection and recall biases. However, we could not conclude that the increased risk was entirely explicable by these biases, leaving open the possibility that mobile phone use increased the risk of acoustic neuroma. Copyright © 2010 Wiley-Liss, Inc.

Pathomorphological study on 106 autopsy cases of Thorotrast-related hepatic malignancies with comparison to non-Thorotrast-related cases

International Nuclear Information System (INIS)

Kojiro, Masamichi; Ito, Yuji

1989-01-01

The pathomorphological features of 106 autopsy cases of Thorotrast-related malignant tumours of the liver were studied and compared to those of non-Thorotrast-related cases. Among the 106 cases, 44 (41.5%) were cholangiocarcinoma, 42 (39.6%) were angiosarcoma, 17 (16.0%) were hepatocellular carcinoma, and three (2.8%) were double cancers. In contrast, in non-Thorotrast-related cases about 90% of the cases were hepatocellular and angiosarcoma was extremely rare. (author)

Struggling doctors in specialist training: a case control study

DEFF Research Database (Denmark)

O'Neill, Lotte; Norberg, Karen; Thomsen, Maria

), or transferred (i.e. had unplanned changes in place of training/ward due to failure to thrive or due to inadequate development of competences), or dropped out (i.e. were dismissed from, had resigned from, or changed their speciality). Controls were a random sample of doctors in the source population, who were......Abstract summary The aim of this cummulative incidence case-control study was to examine: if struggling trainees in medical specialist training (cases) tended to struggle already in medical school or not compared to non-struggling controls, and which performance indicators during medical school...... seemed to predict struggling in postgraduate education if any. The study design is rooted in epidemiological methodology. Struggling doctors in specialist training: a case-control study. It has been reported in the international literature, that around 3-10% of doctors in post-garduate specialist...

Innovative Interpretive Qualitative Case Study Research Method ...

African Journals Online (AJOL)

lc2o

The combined use of case study and systems theory is rarely discussed in the ... Scott, 2002), the main benefit of doing qualitative research is the patience ..... Teaching ICT to teacher candidates ... English Language Teachers. London: Arnold.

Management in Virtual Environments. Case Studies

OpenAIRE

Mazurek, Grzegorz; Gembicki, Michał; Krzemień, Grzegorz; Przegalińska, Aleksandra K.; Starostka, Justyna; Skorulska, Karolina; Prystupa-Rządca, Kaja

2015-01-01

The following publication consists of 12 case studies, which encompass various aspects of the ICT impact on contemporary businesses, focusing – among other things – on such concepts as: crowdsourcing, the internet of things, design thinking, digital entertainment, e-commerce, online and off-line distribution or social media marketing. EEA, Norway Grants Anna Goryńska

Library Virtual Tours: A Case Study

Science.gov (United States)

Ashmore, Beth; Grogg, Jill E.

2004-01-01

Virtual tours delivered via the Web have become a common tool for both instruction and outreach. This article is a case study of the creation of a virtual tour for a university library and is intended to provide others interested in creating a virtual tour of their library the opportunity to learn from the mistakes and successes of fellow…

Using Clinical Gait Case Studies to Enhance Learning in Biomechanics

Science.gov (United States)

Chester, Victoria

2011-01-01

Clinical case studies facilitate the development of clinical reasoning strategies through knowledge and integration of the basic sciences. Case studies have been shown to be more effective in developing problem-solving abilities than the traditional lecture format. To enhance the learning experiences of students in biomechanics, clinical case…

Performance of Wild Fruit Marketing in Nigeria: A Case Study of ...

African Journals Online (AJOL)

Performance of Wild Fruit Marketing in Nigeria: A Case Study of African Star Apple ( Chrysophllum ... This study examined marketing of wild fruits in Nigeria using African Star Apple as a case study. ... EMAIL FULL TEXT EMAIL FULL TEXT

Case Study: A Step-by-Step Guide to Students Writing Case Studies (and Tools for Novice Case Authors)

Science.gov (United States)

Prud'homme-Genereux, Annie

2015-01-01

In experimenting with ways of structuring the assignment and providing guidance to students, the author developed a series of tools that may be of interest to instructors wishing to implement a case-writing assignment in their course. This assignment is more suited for instructors experienced in case writing, as their knowledge of how to design a…

Risk management strategies by Australian farmers: two case studies

OpenAIRE

Nguyen, Nam C.; Wegener, Malcolm K.; Russell, Iean W.; Cameron, Donald; Coventry, David; Cooper, Ian M.

2007-01-01

Australian farmers operate in one of the most risky farming environments in the world. They have to cope with numerous sources of risk including weather uncertainty, variable market prices, and institutional changes in their business management. This paper reports results from two case studies undertaken to examine the issues of farming risks and risk management strategies in Australia. The first case study found that unpredictable weather, financial risk, marketing risk, and personal risk we...

Metabolic interactions in methanogenic and sulfate-reducing bioreactors

NARCIS (Netherlands)

Stams, A.J.M.; Plugge, C.M.; Bok, de F.A.M.; Houten, van B.H.G.W.; Lens, P.N.L.; Dijkman, H.; Weijma, J.

2005-01-01

In environments where the amount of electron acceptors is insufficient for complete breakdown of organic matter, methane is formed as the major reduced end product. In such methanogenic environments organic acids are degraded by syntrophic consortia of acetogenic bacteria and methanogenic archaea.

Interspecies electron transfer in methanogenic propionate degrading consortia

NARCIS (Netherlands)

Bok, de F.A.M.; Plugge, C.M.; Stams, A.J.M.

2004-01-01

Propionate is a key intermediate in the conversion of complex organic matter under methanogenic conditions. Oxidation of this compound requires obligate syntrophic consortia of acetogenic proton- and bicarbonate reducing bacteria and methanogenic archaea. Although H-2 acts as an electron-carrier in

War And Reconstruction: Four Comparative Case Studies

African Journals Online (AJOL)

The four case studies are taken from four different continents, four different wars under .... and revolutionary changes in the structures and power relations in society and ..... general public accept nowadays that although states' rights were the ...

Conservation vs. renewable energy: Cases studies from Hawaii

International Nuclear Information System (INIS)

Yalcintas, Melek; Kaya, Abidin

2009-01-01

State of Hawaii generates about 90 percent of its electricity from imported fossil fuel sources. Thus, there is pressure from both public and policy makers to reduce the State dependency on foreign fossil fuel sources. To this extend, there are incentives created at State and Federal level for both residential and commercial buildings to install photovoltaic (PV) systems. Although such incentives are necessary for long-term objectives, it is shown in this study that retrofitting inefficient old building-equipment is another viable source to reduce the State of Hawaii's electricity demand. Four case studies are presented to illustrate that building-equipment retrofitting is a viable and necessary tool for increasing the energy efficiency of buildings. Each case study presents an equipment retrofit project electricity savings with its payback periods, and compares with equivalent electricity capacity and economics PV systems in Honolulu, Hawaii. The case studies show that energy savings from retrofit projects ranged from 28% to 61% for individual equipment retrofits. These results indicate that equipment retrofitting with energy-efficient alternatives is about 50% or more cost-effective than installing PV systems. This is so even when large renewable energy tax incentives provided by the Federal and State Governments are taken into account.

Singing well-becoming: Student musical therapy case studies

Directory of Open Access Journals (Sweden)

Tim Murphey

2014-01-01

Full Text Available Much research supports the everyday therapeutic and deeper socialneurophysiological influence of singing songs alone and in groups (Austin, 2008; Cozolino, 2013; Sacks, 2007. This study looks at what happens when Japanese students teach short English affirmation songlet-routines to others out of the classroom (clandestine folk music therapy. I investigate 155 student-conducted musical case studies from 7 semester-long classes (18 to 29 students per class over a 4-year period. The assignments, their in-class training, and their results are introduced, with examples directly from their case studies. Each class published their own booklet of case studies (a class publication, available to readers online for research replication and modeling. Results show that most primary participants enjoyed spreading these positive songlets as they became “well-becoming agents of change” in their own social networks. “Well-becoming” emphasizes an agentive action or activity that creates better well-being in others, an action such as the sharing or teaching of a songlet. The qualitative data reveals a number of types of well-becoming such as social and familial bonding, meaning-making, teaching-rushes, and experiencing embodied cognition. The project also stimulated wider network dissemination of these well-becoming possibilities and pedagogical insights.

Singularity analysis in nonlinear biomathematical models: Two case studies

International Nuclear Information System (INIS)

Meletlidou, E.; Leach, P.G.L.

2007-01-01

We investigate the possession of the Painleve Property for certain values of the parameters in two biological models. The first is a metapopulation model for two species (prey and predator) and the second one is a study of a sexually transmitted disease, into which 'education' is introduced. We determine the cases for which the systems possess the Painleve Property, in particular some of the cases for which the equations can be directly integrated. We draw conclusions for these cases

[A case study on duty of care in professional nursing].

Science.gov (United States)

Huang, Hui-Man; Liao, Chi-Chun

2013-08-01

Nurses are expected to discharge their duty of care effectively and professionally to prevent medical negligence. Only three articles have previously focused on medical negligence. Duty of care and medical negligence in nursing are topics that have been neglected in Taiwan. (1) Classify the duty of care of professional nurses; (2) Investigate the facts and disputes in the current case; (3) Clarify the legal issues involved with regard to duty-of-care violations in the current case; (4) Explore the causal relationships in a legal context between nurses' duty-of-care violations and patient harm / injury. Literature analysis and a case study are used to analyze Supreme Court Verdict No.5550 (2010). Duty of care for nursing professionals may be classified into seven broad categories. Each category has its distinct correlatives. In nursing practice, every nursing behavior has a corresponding duty. In this case, the case study nurse did not discharge her obstetric professional duty and failed to inform the doctor in a timely manner. Negligence resulted in prenatal death and the case study nurse was found guilty. In order to prevent committing a crime, nurses should gain a better understanding of their duty of care and adequately discharge these duties in daily practice.

Effectiveness of integrating case studies in online and face-to-face instruction of pathophysiology: a comparative study.

Science.gov (United States)

Saleh, Suha M; Asi, Yara M; Hamed, Kastro M

2013-06-01

Due to growing demand from students and facilitated by innovations in educational technology, institutions of higher learning are increasingly offering online courses. Subjects in the hard sciences, such as pathophysiology, have traditionally been taught in the face-to-face format, but growing demand for preclinical science courses has compelled educators to incorporate online components into their classes to promote comprehension. Learning tools such as case studies are being integrated into such courses to aid in student interaction, engagement, and critical thinking skills. Careful assessment of pedagogical techniques is essential; hence, this study aimed to evaluate and compare student perceptions of the use of case studies in face-to-face and fully online pathophysiology classes. A series of case studies was incorporated into the curriculum of a pathophysiology class for both class modes (online and face to face). At the end of the semester, students filled out a survey assessing the effectiveness of the case studies. Both groups offered positive responses about the incorporation of case studies in the curriculum of the pathophysiology class. This study supports the argument that with proper use of innovative teaching tools, such as case studies, online pathophysiology classes can foster a sense of community and interaction that is typically only seen with face-to-face classes, based on student responses. Students also indicated that regardless of class teaching modality, use of case studies facilitates student learning and comprehension as well as prepares them for their future careers in health fields.

Pathomorphological study on 106 autopsy cases of Thorotrast-related hepatic malignancies with comparison to non-Thorotrast-related cases

International Nuclear Information System (INIS)

Kojiro, Masamichi; Ito, Yuji

1989-01-01

The pathomorphological features of 106 autopsy case of Thorotrast (TH)-related malignant tumours of the liver were studied and compared to those of non-Thorotrast-related cases. Among the 106 cases, 44 (41.5%) were cholangiocarcinoma (CHC), 42(39.6%) were angiosarcoma (AGS), 17(16.0%) were hepatocellular carcinoma (HCC), and three (2.8%) were double cancers. In contrast, in non-Thorotrast-related cases about 90% of the cases were hepatocellular and angiosarcoma was extremely rare. (author)

The Importance of Interfaces: A HW/SW Codesign Case Study

DEFF Research Database (Denmark)

Jensen, Dan C. Raun; Madsen, Jan; Pedersen, Steen

1997-01-01

This paper presents a codesign case study in image analysis. The main objective is to stress the importance of handling HW/SW interfaces more precisely at the system level. In the presented case study, there is an intuitive and simple HW/SW interface, which is based upon the functional modules...

Incorporating Case Studies into a World Food and Population Course

Science.gov (United States)

Econopouly, Bethany F.; Byrne, Patrick F.; Johnson, Marc A.

2010-01-01

The use of case studies in college courses can increase student engagement with the subject matter and improve analytical, problem-solving, and communication skills. Case studies were introduced in a relatively large (54 students) undergraduate world food and population course at Colorado State University in the spring semester of 2008 and…

Case study of the interdisciplinary integration in an IST-E3 project

DEFF Research Database (Denmark)

Jørgensen, Ulrik

2002-01-01

Case study of a specific IST-E3 project funded by the EU commissions 5th framework program. The case study highlights the difficulties in integrating different disciplinary approaches and suggests that a more openended research strategy should be applied by the commission.......Case study of a specific IST-E3 project funded by the EU commissions 5th framework program. The case study highlights the difficulties in integrating different disciplinary approaches and suggests that a more openended research strategy should be applied by the commission....

Failures of austenitic stainless steel components during storage: Case studies

International Nuclear Information System (INIS)

Shah, B.K.; Rastogi, P.K.; Sinha, A.K.; Kulkarni, P.G.

1993-01-01

Three studies of failures of austenitic stainless steel components during storage are described. In all cases, stress corrosion cracking was the failure mode by the action of residual stress alone. However, the source of residual stress was different for each case. Case 1 was the failure of a sample tube header for a pressurized heavy water reactor (PHWR). In Case 2, a heat exchanger shell failed during a hydrotest in a fertilizer plant. Cases concerned the cracking of type 304L plates used for spent fuel pool lining of a nuclear power station

Case studies of nurseries in Malawi

DEFF Research Database (Denmark)

Namoto, M.; Likoswe, M.G.

This study of 42 case studies of nurseries was made as part of a major sample survey of 360 nurseries in 6 districts in Malawi. The purpose of the study was to let the small nurseries in the country explain in their own words how they source seed, how and for whom they produce seedlings......, and to explain about their problems and opportunities in the nursery business. The assessment was made within the framework of Improved Seed Supply for Agroforestry in African Countries (ISSAAC), a Danida supported programme implemented in cooperation between Forest & Landscape Denmark and World Agroforestry...

The role of context in case study selection: An international business perspective

OpenAIRE

Poulis, K; Poulis, E; Plakoyiannaki, ME

2013-01-01

The extant methodological literature has challenged case selection in qualitative case study research for being arbitrary or relying too much on convenience logic. This paper aims to address parts of such criticism on the rigour of case selection through the presentation of a sampling framework that promotes contextualisation and thoroughness of sampling decisions in the study of international phenomena. This framework emerged from an inductive process following an actual case study project i...

Using Significant Geologic Hazards and Disasters to Focus Geoethics Case Studies

Science.gov (United States)

Cronin, V. S.

2015-12-01

Ethics education since classical times has involved the consideration of stories, parables, myths, fables, allegories and histories. These are the ancient equivalents of case studies. Modern case studies are used in applied-ethics courses in law, engineering, business, and science. When used in a geoscience course, geoethical case studies can enrich a student's understanding of the relationships between issues of geoscience, engineering, sociology, business, public policy and law - all with an ethical dimension. Perhaps more importantly, real cases affected real people. Students develop a strong empathetic connection to the people involved, enhancing students' drive to understand the interconnected layers of the cases. Students might begin to appreciate that geoscientists can help to avoid or alleviate human suffering -- that their careers can have meaning and purpose beyond simply earning a paycheck. Geologic disasters in which losses could have been predicted, avoided or minimized are quite effective as cases. Coupling a "disaster" case with a comparable "hazard" case is particularly effective. For example, there are many places along the San Andreas Fault in California where [1] significant coseismic displacement has occurred during historical times, [2] structures that are still inhabited were built along or across active traces prior to the Alquist-Priolo Earthquake Fault Zoning Act in 1971, and [3] inhabited structures have been built legally since 1971 within a few tens of feet of active traces. The question students confront is whether society ought to allow habitable structures to be built very near to a major active fault. This topic allows students to work with issues of law, history, seismology, seismic site response, crustal deformation adjacent to active faults, building codes and, ultimately, ethics. Similar progressions can be developed for other major geologic hazards, both natural and man-made, such as floods, landslides, erosion along rivers and

In-Depth Case Studies of Superfund Reuse

Science.gov (United States)

SRI’s in-depth case studies explore Superfund reuse stories from start to finish. Their purpose is to see what redevelopment strategies worked, acknowledge reuse barriers and understand how communities overcame the barriers to create new reuse outcomes.

HYDROGEOLOGIC CASE STUDIE(PRESENTATION FOR MNA WORKSHOP)

Science.gov (United States)

Hydrogeology is the foundation of subsurface site characterization for evaluations of monitored natural attenuation (MNA). Three case studies are presented. Examples of the potentially detrimental effects of drilling additives on ground-water samples from monitoring wells are d...

Clinical study on 44 cases of femoral hernia

International Nuclear Information System (INIS)

Yamamoto, Ryo; Shinozaki, Hiroharu; Kase, Kenichi; Kobayashi, Kenji; Sasaki, Junichi

2012-01-01

Femoral hernia is a surgical disease that is frequently associated with incarceration and necessitates emergency surgery. However, there are only a few studies referred which have compared emergency and elective surgery for femoral hernias. We retrospectively reviewed the clinical characteristics of patients diagnosed as having femoral hernia between 2005 and 2009 in our institution. The clinical features of emergency repairs were compared with those of elective ones, and diagnostic values of preoperative diagnostic modalities were studied. The mean age of the patients was 73±12 years. Females comprised 68% of the cases, and right femoral hernias comprised 70% of the cases. Incarceration was associated with 66% of the cases (29 patients), and emergency surgery was performed in 52% of the patients (23 patients). Bowel resection was performed in 32% of the cases (14 patients). The mean age, body temperature, white blood cell (WBC) count, and LDH value were higher in the emergency repairs than in the elective one, and most of the hernias were repaired with McVay's procedure. CT scans had a high diagnostic value in detecting femoral hernias (44%) and incarceration (88%). It was confirmed that femoral hernias were frequently associated with incarceration and CT scan has a high diagnostic value in femoral hernias. (author)

Marketing and clinical trials: a case study

Directory of Open Access Journals (Sweden)

Entwistle Vikki A

2007-11-01

Full Text Available Abstract Background Publicly funded clinical trials require a substantial commitment of time and money. To ensure that sufficient numbers of patients are recruited it is essential that they address important questions in a rigorous manner and are managed well, adopting effective marketing strategies. Methods Using methods of analysis drawn from management studies, this paper presents a structured assessment framework or reference model, derived from a case analysis of the MRC's CRASH trial, of 12 factors that may affect the success of the marketing and sales activities associated with clinical trials. Results The case study demonstrates that trials need various categories of people to buy in – hence, to be successful, trialists must embrace marketing strategies to some extent. Conclusion The performance of future clinical trials could be enhanced if trialists routinely considered these factors.

Obstacles to action in arthritis: a community case-control study.

Science.gov (United States)

Hutton, Ingrid; Gamble, Greg; McLean, Grant; Butcher, Hugh; Gow, Peter; Dalbeth, Nicola

2009-07-01

Despite the benefits of physical activity, people with arthritis are less active than the general population. The aim of this study was to determine the motivators and obstacles to physical activity for adults with arthritis. Participants were identified from the Obstacles to Action Study, a community based study of 8163 adults, which explored barriers and motivators to physical activity. A 1:1 case-control study was designed; cases were identified as those participants who reported arthritis (n = 1106). Each case was matched with an age, sex and ethnicity-matched non-arthritis control (n = 1106). Cases were less likely to achieve recommended physical activity targets (58.8% vs. 68.1% P = 0.00001). Furthermore, fewer people with arthritis believed that physical activity would help them lead healthy lives (86.7% vs. 91.3% P = 0.006) or viewed physical activity as a priority (53.8% vs. 59.8% P = 0.005). Cases were less confident in their abilities to try a new activity (37.1% vs. 43.7% P = 0.002) or maintain a healthy weight (65.0% vs. 74.3% P = 0.00001). Cases also reported greater negative impact scores for barriers to activity, particularly arthritis, accessibility, cost and discomfort while exercising. Motivators and environmental barriers to activity were similar for cases and controls. These findings persisted after adjusting for educational level, body mass index and comorbidities. People with arthritis are less active and demonstrate different attitudes toward physical activity. Although people with arthritis identify similar environmental barriers, they have different psychosocial barriers. In order to design effective physical activity programs for people with arthritis, these barriers must be specifically addressed.

Nanomaterial Case Studies: Nanoscale Titanium Dioxide in ...

Science.gov (United States)

EPA announced the availability of the final report, Nanomaterial Case Studies: Nanoscale Titanium Dioxide in Water Treatment and in Topical Sunscreen. This report is a starting point to determine what is known and what needs to be known about selected nanomaterials as part of a process to identify and prioritize research to inform future assessments of the potential ecological and health implications of these materials. Two specific applications of nanoscale titanium dioxide (nano-TiO2) are considered: (1) as an agent for removing arsenic from drinking water; and (2) as an active ingredient in topical sunscreen. These case studies are organized around a comprehensive environmental assessment (CEA) framework that combines a product life cycle perspective with the risk assessment paradigm. They are intended to help identify what may need to be known in order to conduct a comprehensive environmental assessment of the potential risks related to nano-TiO2. These “case studies” do not represent completed or even preliminary assessments, nor are they intended to serve as a basis for risk management decisions in the near term on these specific uses of nano TiO2. Rather, the intent is to use this document in developing the scientific and technical information needed for future assessment efforts.

Risk Factors for Anemia in Pregnancy: A Case Control Study

Directory of Open Access Journals (Sweden)

Rutuja Pundkar

2017-12-01

Full Text Available Background: Aim of the study was to find the risk factors leading to Anemia in pregnancy. The main objective was to study the various sociodemographic factors leading to anemia. And to assess the knowledge about anemia among study participants. Material and methods: The present Case control study was carried out at Primary Health Centre, to determine the risk factors leading to anemia in pregnancy. A total of 308 pregnant females were registered. Among them two groups were made, group I cases and group II controls. Each group had 50 cases each. Laboratory test were done and females having hemoglobin less than 11mg/dl were considered anemic. Anemic females were considered cases and females having Hb >11mg/dl were considered controls. Data analysis was done using SPSS software. Results: The overall mean haemoglobin (Hb was 11.55g/dL in controls, whereas it was seen that among the cases it was 9.58g/dL.It would seem that diet, family size, education, social class, gravida and parity are associated with anemia in pregnancy. Conclusion: After adjusting for all the possible covariates there seems to be significant association between Hb levels and age group, education level, family size, diet, gravida and parity.

425 Case study

African Journals Online (AJOL)

Marinda

Anaesthesia management of acute aortic dissection type B in ... of a severe, constant abdominal and chest pain radiating to the ... Continuous spinal anaesthesia was induced ... these cases surgical intervention is critical.1,2 Type B of AAD is.

Case studies in atomic collision physics

CERN Document Server

McDaniel, Earl Wadsworth

1972-01-01

Case Studies in Atomic Collision Physics II focuses on studies on the role of atomic collision processes in astrophysical plasmas, including ionic recombination, electron transport, and position scattering. The book first discusses three-body recombination of positive and negative ions, as well as introduction to ionic recombination, calculation of the recombination coefficient, ions recombining in their parent gas, and three-body recombination at moderate and high gas-densities. The manuscript also takes a look at precision measurements of electron transport coefficients and differential cr

Guide to good practices for developing and conducting case studies: DOE handbook

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-01-01

Learning from experience is often very costly to a facility in terms of injured personnel, damaged equipment, and wasted time. Learning from the experience gained at the facility and from industry can prevent repeating costly mistakes. This guide contains a method for learning from experience to prevent mistakes from occurring; that method is the case study. This guide describes how to develop and present case studies. This guide provides the instructional developer insight on the best kind of case study to use and includes examples of the various types of case studies.

Operating an Advertising Programmatic Buying Platform: A Case Study

Directory of Open Access Journals (Sweden)

Juan Carlos Gonzalvez-Cabañas

2016-03-01

Full Text Available This paper analyses how new technological developments and the possibilities generated by the internet are shaping the online advertising market. More specifically it focuses on a programmatic advertising case study. The origin of the problem is how publishers resort to automated buying and selling when trying to shift unsold inventory. To carry out our case study, we will use a programmatic online advertising sales platform, which identifies the optimal way of promoting a given product. The platform executes, evaluates, manages and optimizes display advertising campaigns, all in real-time. The empirical analysis carried out in the case study reveals that the platform and its exclusion algorithms are suitable mechanisms for analysing the performance and efficiency of the various segments that might be used to promote products. Thanks to Big Data tools and artificial intelligence the platform performs automatically, providing information in a user-friendly and simple manner.

The Role of Information Systems and Technology in Case Management: a case study in health and welfare insurance

Directory of Open Access Journals (Sweden)

Helen Richardson

2003-05-01

Full Text Available This study reports the role of information system and technology (IST in supporting case management at the Accident Compensation Corporation (ACC of New Zealand. Case management is a managerial approach that seeks to gain improved business performance by enhancing both employee and customer satisfaction. Despite millions of dollars spent annually by health, social, and insurance agencies in automating case management, little research has been conducted into the role of IST in this practice. The findings of this study show that for ACC, IST’s most valuable role is enhancing the relationship between client and case manager rather than replacing it for, even after the addition of IST, the most valuable knowledge continues to accrue from the face to face interaction of client and case manager. The findings also show two distinct phases to the development of case managers as knowledge workers. The first phase focuses on control of the processes and the second on the delivery and sharing of information resources.

The Misconception of Case-Control Studies in the Plastic Surgery Literature: A Literature Audit.

Science.gov (United States)

Hatchell, Alexandra C; Farrokhyar, Forough; Choi, Matthew

2017-06-01

Case-control study designs are commonly used. However, many published case-control studies are not true case-controls and are in fact mislabeled. The purpose of this study was to identify all case-control studies published in the top three plastic surgery journals over the past 10 years, assess which were truly case-control studies, clarify the actual design of the articles, and address common misconceptions. MEDLINE, Embase, and Web of Science databases were searched for case-control studies in the three highest-impact factor plastic surgery journals (2005 to 2015). Two independent reviewers screened the resulting titles, abstracts, and methods, if applicable, to identify articles labeled as case-control studies. These articles were appraised and classified as true case-control studies or non-case-control studies. The authors found 28 articles labeled as case-control studies. However, only six of these articles (21 percent) were truly case-control designs. Of the 22 incorrectly labeled studies, one (5 percent) was a randomized controlled trial, three (14 percent) were nonrandomized trials, two (9 percent) were prospective comparative cohort designs, 14 (64 percent) were retrospective comparative cohort designs, and two (9 percent) were cross-sectional designs. The mislabeling was worse in recent years, despite increases in evidence-based medicine awareness. The majority of published case-control studies are not in fact case-control studies. This misunderstanding is worsening with time. Most of these studies are actually comparative cohort designs. However, some studies are truly clinical trials and thus a higher level of evidence than originally proposed.

case study of ramat park benin city

African Journals Online (AJOL)

user

SETTLEMENT: CASE STUDY OF RAMAT PARK BENIN CITY. E. S. Okonofua1, R. ... region on a daily basis. The movement of ... with major road networks [2]. In order to ease ... led to series of research and development of traffic noise models.

Servant Leadership through Distance Learning: A Case Study

Science.gov (United States)

Russell, Eric James

2013-01-01

This qualitative study explored the influence a distance learning servant leadership course had on the emergency service students' understanding of leadership. The research study utilized a case study design in order to tell the story of the lived experiences of the participants. The setting for the study was a state university in Utah, with the…

Iron oxides alter methanogenic pathways of acetate in production water of high-temperature petroleum reservoir.

Science.gov (United States)

Pan, Pan; Hong, Bo; Mbadinga, Serge Maurice; Wang, Li-Ying; Liu, Jin-Feng; Yang, Shi-Zhong; Gu, Ji-Dong; Mu, Bo-Zhong

2017-09-01

Acetate is a key intermediate in anaerobic crude oil biodegradation and also a precursor for methanogenesis in petroleum reservoirs. The impact of iron oxides, viz. β-FeOOH (akaganéite) and magnetite (Fe 3 O 4 ), on the methanogenic acetate metabolism in production water of a high-temperature petroleum reservoir was investigated. Methane production was observed in all the treatments amended with acetate. In the microcosms amended with acetate solely about 30% of the acetate utilized was converted to methane, whereas methane production was stimulated in the presence of magnetite (Fe 3 O 4 ) resulting in a 48.34% conversion to methane. Methane production in acetate-amended, β-FeOOH (akaganéite)-supplemented microcosms was much faster and acetate consumption was greatly improved compared to the other conditions in which the stoichiometric expected amounts of methane were not produced. Microbial community analysis showed that Thermacetogenium spp. (known syntrophic acetate oxidizers) and hydrogenotrophic methanogens closely related to Methanothermobacter spp. were enriched in acetate and acetate/magnetite (Fe 3 O 4 ) microcosms suggesting that methanogenic acetate metabolism was through hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers. The acetate/β-FeOOH (akaganéite) microcosms, however, differed by the dominance of archaea closely related to the acetoclastic Methanosaeta thermophila. These observations suggest that supplementation of β-FeOOH (akaganéite) accelerated the production of methane further, driven the alteration of the methanogenic community, and changed the pathway of acetate methanogenesis from hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers to acetoclastic.

Context Matters: Increasing Understanding with Interactive Clicker Case Studies

Science.gov (United States)

Lundeberg, Mary A.; Kang, Hosun; Wolter, Bjorn; delMas, Robert; Armstrong, Norris; Borsari, Bruno; Boury, Nancy; Brickman, Peggy; Hannam, Kristi; Heinz, Cheryl; Horvath, Thomas; Knabb, Maureen; Platt, Terry; Rice, Nancy; Rogers, Bill; Sharp, Joan; Ribbens, Eric; Maier, Kimberly S.; Deschryver, Mike; Hagley, Rodney; Goulet, Tamar; Herreid, Clyde F.

2011-01-01

Although interactive technology is presumed to increase student understanding in large classes, no previous research studies have empirically explored the effects of Clicker Cases on students' performance. A Clicker Case is a story (e.g., a problem someone is facing) that uses clickers (student response systems) to engage students in understanding…

Evaluating a Tacit Knowledge Sharing Initiative: A Case Study

Science.gov (United States)

Gubbins, Claire; Corrigan, Siobhan; Garavan, Thomas N.; O'Connor, Christy; Leahy, Damien; Long, David; Murphy, Eamonn

2012-01-01

Purpose: This paper aims to present a case study illustrating the issues involved in the tacit knowledge conversion process and to determine whether such conversion delivers value to the organisation in terms of business value and return on investment (ROI). Design/methodology/approach: A single-case multiple baseline participants experimental…

Enhanced Web-Based Otitis Study Case vs. Simple Paper-Case: Impact on Medical Student Objective Structured Clinical Exam Performance

Directory of Open Access Journals (Sweden)

Michael H. Malloy, M.D., M.S.

2002-01-01

Full Text Available Background: Distance education methods have taken on greater importance as medical student education has moved off campus into the community. What the best methods are for conveying information to students at distant sites has not been determined. Objective: To determine if students at distant community sites who received an otitis media study case by e-mail that was enhanced with a referral to a web-based otitis study case, performed better on otitis OSCE stations than students who received the same case not enhanced with visuals or referrals to a web-based otitis case. Design/Methods: Students were randomized by community site to receive either the enhanced (E or simple otitis study case (S. Students were e-mailed an otitis media study case during the 5th week of the rotation. Those randomized to the E-case received a case that started with a case scenario followed by a "Task" that instructed them to go to this web address: http://www.aap.org/otitismedia/www/vc/ear/index.cfm (American Academy of Pediatrics Otitis Web Site. They were then to select "Case 1" which was a continuation of the case scenario present on their e-mail. A list of learning objectives was also printed on the e-mail. Students receiving the S-case viewed the same case scenario and objectives, but were not instructed to go to the web page. All students rotated through two OSCE otitis stations. In the first station they interviewed a simulated patient(OSCE-SP and counseled her on the management of her 12 month old with otitis. Within that station they viewed a video of a pneumoscopic exam of two ears, one ear with otitis and the other ear normal. At the 2nd otitis station the student presented the case to a faculty and was asked a series of questions about otitis media(OSCE-PR. Scores on the two stations were compared by group. Results: There were 198 students who took the OSCE. 178 (90% responded to a survey that indicated they had opened and read the e-mailed case. There

Financial Shenanigans : A Case Study in Malaysia

OpenAIRE

Ooi, Ki Wei

2013-01-01

This study investigates the financial shenanigan cases which subject to the enforcement actions by the Malaysian Securities Commission between 2006 and 2011 for alleged financial misreporting. The scope of this study includes the attempts used, causes and consequences of the financial shenanigans and the post-financial shenanigans recovery plans devised to turnaround the companies. This study finds that the most common attempt used by the sample companies is overstating the revenue, follows b...

Financial Shenanigans : A Case Study of Nigeria

OpenAIRE

Onitilo, Nnenna Chidimma

2015-01-01

This study investigates the identified cases of financial shenanigans in between 2001 and 2009 in Nigeria. The scope of this study includes the identification of the common attempts and approaches used by companies and the motivations for financial shenanigans. A cross country comparison of the characteristics of the corporate reporting environments between Nigeria and Malaysia was also carried out. This study finds that the most common attempt used by the sample companies are majorly revenue...

Towards an Understanding of the Impacts of Localized Real Case Studies

Directory of Open Access Journals (Sweden)

Mathews Nkhoma

2014-02-01

Full Text Available This research aims to understand the mediating roles of learning engagement, learning process and learning experience in influencing students' outcomes through case study pedagogy. It gathered students' responses to localised real case studies discussed in Information Systems classes. Case knowledge and perception were used to measure students' learning outcomes in order to determine the degree to which students induced course concepts and how they felt the cases impacted their understanding of the course. Revised student engagement questionnaire was used to measure various forms of engagement such as skills, emotion, participation, and performance while revised study process questionnaire served to assess the extent to which students used deep or surface approach to learning. Additionally, seven roles of feedback were used to analyse students' learning experience. Finally, group performance and individual's positive perceptions of group learning were tested to measure students' learning outcomes. Structural equation modelling was used to test the causal model. Analysis revealed that case knowledge and case perception had positive influence on students' skill engagement and emotional engagement but only case knowledge had a positive impact on the functions of feedback.

Performance of air sparging systems -- A review of case studies

International Nuclear Information System (INIS)

Bass, D.H.; Brown, R.A.

1995-01-01

In situ air sparging is a commonly used remediation technology which volatilizes and enhances aerobic biodegradation of contamination in Groundwater and saturated zone soil. Recently, some questions have been raised regarding the effectiveness of air sparging. To address these questions the results of 21 sparging case studies have been compiled to shed light on how well air sparging achieves permanent reduction in groundwater contaminant concentrations. The case studies included both chlorinated solvents and petroleum hydrocarbon contamination, and covered a wide range of soil conditions and sparge system parameters. In each case study, groundwater concentrations were compared before sparging was initiated, just before sparging was terminated, and in the months following shutdown of the sparging system

Single case studies as a means for developing psychological theories.

Science.gov (United States)

Skvortsov, Anatoliy; Romashchuk, Alexander

2015-12-01

The Socratic function of single case studies (SCSs) is described in its relation to the problem of scientific theory development. Contrary to the traditional point of view, the single case study is not a demonstration or verification of theoretical concepts, but a method of their generation and opportunity for analysis of their interrelations. Considering the case study from the perspective of the Socratic function brings to light important conclusions about the ecological validity of theory development. The essential features of the Socratic function are illustrated using the example of the famous Romantic Essays of Alexandr Luria. © 2015 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Using Case Studies in Business Education to Promote Networked Thinking: Findings of an Intervention Study

Science.gov (United States)

Pilz, Matthias; Zenner, Lea

2018-01-01

Case studies are central to the way management is currently taught at universities. Among other benefits attributed to the case study method is that it promotes networked thinking by learners. Networked thinking takes account of interactions and repercussions, making it crucial to decision-making within the complex system of rules that shapes…

Overview of the Case Studies

DEFF Research Database (Denmark)

Cameron, Ian; Gani, Rafiqul

2011-01-01

A series of case studies are used to illustrate many of the underlying modelling principles within the book. To facilitate this, the ICAS-MoT modelling tool has been used. A wide range of application areas have been chosen to ensure that the principal concepts of effective and efficient modelling...... are exercised. Conceptual frameworks for single and multiscale problems are given and explained. The importance of the steps is also explained, through annotated schematic diagrams. The important issues around workflow and data flow are given in diagrammatic form....

Physics in Industry: A Case Study

Science.gov (United States)

Pratt-Ferguson, Ben

2007-10-01

Often ignored and sometimes even considered ``black sheep'' by the university & government-lab physicists, many industrial physicists continue making valuable scientific contributions in diverse areas, from computer science to aero and thermo-dynamics, communications, mathematics, engineering, and simulation, to name a few. This talk will focus on what industrial physicists do, what preparations are beneficial to obtaining a first industrial job, and what the business environment is like for physicists. The case study will be that of the author, starting with undergraduate and graduate studies and continuing on to jobs in industry.

An autopsy study of 74 cases of cut throat injuries

Directory of Open Access Journals (Sweden)

Dinesh Rao

2015-12-01

Full Text Available The present prospective autopsy study was carried out during the period July 2009 to May 2012 in Kingston, Jamaica. A total of 74 cases of cut throat injury were studied. All the cut throat injuries irrespective of those directly or indirectly contributing to the death were studied. Males dominated the list of victims, contributing to 71.62% (n = 53. Majority of those were in the age group 21–30 (n = 25 and 31–40 (n = 26 which contributed to 33.78% and 35.13% respectively. Majority of the cases were homicides contributing to 97.29% (n = 72 of cases, only 2.7% were suicides and accidental cut throat were never reported. Males dominated the homicides category contributing to 72.22% (n = 52 of the cases. Gang and relationship crisis (homosexual and heterosexual were the major motivating factors, each contributing to 39.19% (n = 29 and 32.43% (n = 24 of the cases, respectively. The disease suffered by individuals were the least motivating factors contributing to 1.35% of cases (n = 01. The most common cause of death was exsanguinations in 49.95% (n = 34 of cases followed closely by asphyxia due to aspiration of blood i.e. 36.49% (n = 27 of cases and air embolism was the least cause of death, contributing to 4.05% (n = 03 of cases. Cut throat injury was associated with other injuries like gunshot wound, chop wounds and stab wounds in 13.52% of (n = 10 autopsies. Chop injuries contributed to maximum number of other injuries in homicides (n = 46. The most preferred place for the crime was an open field or farm (n = 26. Majority of the cut throat wounds were situated in zone II level contributing to 66.21% (n = 49 of cases. Majority of the wounds were directed from left to right in 75.68% (n = 56 of cases and the cervical vertebra was affected in 8.11% (n = 06 of cases. Major weapon of choice was machete contributing to 83.78% (n = 62 of injuries. The low income group was the most affected group contributing to 91

Postponed variety creation: case study in consumer electronics retail

DEFF Research Database (Denmark)

Appelqvist, Patrik; Gubi, Ebbe

2004-01-01

Purpose – Postponement is known as a way to reduce risk and inventories while still providing high product variety and acceptable response times. The paper is a case study that uses simulation for quantifying these benefits for a consumer electronics company. Design/methodology/approach – Improve......Purpose – Postponement is known as a way to reduce risk and inventories while still providing high product variety and acceptable response times. The paper is a case study that uses simulation for quantifying these benefits for a consumer electronics company. Design...... is beneficial in retail. Findings – In the case company, shop inventory is necessary for high-volume and low-variety products. Postponing variety creation to shops has the potential to decrease inventories for these products by 40-80 per cent. The benefits of postponement depend on delivery speed requirement......, product value, product variety and shop size. Research limitations/implications – Many contributions on postponement have been conceptual. This study contains a quantitative test. The study considers both the spatial dimension (where) and the temporal dimension (when) of postponement. Practical...

Postponed variety creation: case study in consumer electronics retail

DEFF Research Database (Denmark)

Appelqvist, Patrik; Gubi, Ebbe

2005-01-01

Purpose – Postponement is known as a way to reduce risk and inventories while still providing high product variety and acceptable response times. The paper is a case study that uses simulation for quantifying these benefits for a consumer electronics company. Design/methodology/approach – Improve......Purpose – Postponement is known as a way to reduce risk and inventories while still providing high product variety and acceptable response times. The paper is a case study that uses simulation for quantifying these benefits for a consumer electronics company. Design...... is beneficial in retail. Findings – In the case company, shop inventory is necessary for high-volume and low-variety products. Postponing variety creation to shops has the potential to decrease inventories for these products by 40-80 per cent. The benefits of postponement depend on delivery speed requirement......, product value, product variety and shop size. Research limitations/implications – Many contributions on postponement have been conceptual. This study contains a quantitative test. The study considers both the spatial dimension (where) and the temporal dimension (when) of postponement. Practical...

Humanitarian logistics: Review and case study of Zimbabwean experiences

Directory of Open Access Journals (Sweden)

Charles Mbohwa

2010-11-01

Full Text Available This paper reviews and presents findings on mini-case studies done on the difficulties and problems faced by humanitarian organisations in running logistics systems in Zimbabwe. Document analysis was done and this was complemented by mini-case studies and semi-structured interviews and site visits. Mini-case studies of the operations of the World Food Programme, the International Red Cross Society and the Zimbabwe Red Cross Society, the World Health Organisation, the United Nations Children's Fund and the Zimbabwean Civil Protection Organisation in Zimbabwe are discussed. These clarify the difficulties and problems faced such as the lack of trained logistics personnel, lack of access to specialised humanitarian logistics courses and research information, the difficulty in using and adapting existing logistics systems in attending to humanitarian logistics and the lack of collaborative efforts that address the area specifically. This study seeks to use primary and secondary information to inform decision-making in humanitarian logistics with possible lessons for neighbouring countries, other regions in Africa and beyond. Activities on collaborative networks that are beneficial to humanitarian logistics are also suggested.

Climate wise case study compendium: Report 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-02-01

This case study compendium is one of several Climate Wise tools available to help interested companies identify cost-effective options. Climate Wise, a private-public partnership program, is a key Federal initiative to return greenhouse gas emissions to 1990 levels by 2000.

Hydrocarbon storage caverns overhaul: A case study

Energy Technology Data Exchange (ETDEWEB)

McDougall, N. [Bayer Inc., Sarnia, ON (Canada)

1998-09-01

Case studies of four hydrocarbon storage cavern overhauls by Bayer Inc., of Sarnia during the period 1993 to 1997 were reviewed and the lessons learned were discussed. Discussions included inspection requirements for each of the caverns, the logistics and planning plant production around the cavern outages, site and cavern preparation, including removal of the casing slips from the well heads. It was emphasized that cavern overhauls can be expensive operations, unless preceded by proper planning. The largest variable cost is likely to be rig time at about $ 2,000 per day. Planning for the unexpected with thoughtful contingencies can reduce costs and avoid expensive delays.

Brand Extension: a Case Study of Starbucks

OpenAIRE

Bokii, Artem

2017-01-01

The thesis investigates the topic of brand extension and its importance in the business practice of companies. The theoretical part of the research outlines the key theoretical aspects related to brand and brand extension. The practical part investigates the case study of Starbucks brand extension and compares it with other famous brand extension cases. The paper illustrates how Starbucks brand extension from coffee onto the ice cream market had been successful on the initial stage, and how i...

Transformative Learning through Music: Case Studies from Brazil

Science.gov (United States)

Qi, Nan; Veblen, Kari K.

2016-01-01

In this study we consider meaningful, emancipatory, and affirming music-making in Brazil through the lens of five case studies. Each illustrates aspects of transformative theory through music-making in music education as advanced by Mezirow, Freire, and contemporary Brazilian music educators.

Qualitative methodology in a psychoanalytic single case study

DEFF Research Database (Denmark)

Grünbaum, Liselotte

features and breaks in psychotherapy investigated. One aim of the study was to contribute to the development of a transparent and systematic methodology for the psychoanalytic case study by application of rigorous qualitative research methodology. To this end, inductive-deductive principles in line...

Best practices in intercultural health: five case studies in Latin America

Science.gov (United States)

Mignone, Javier; Bartlett, Judith; O'Neil, John; Orchard, Treena

2007-01-01

The practice of integrating western and traditional indigenous medicine is fast becoming an accepted and more widely used approach in health care systems throughout the world. However, debates about intercultural health approaches have raised significant concerns. This paper reports findings of five case studies on intercultural health in Chile, Colombia, Ecuador, Guatemala, and Suriname. It presents summary information on each case study, comparatively analyzes the initiatives following four main analytical themes, and examines the case studies against a series of the best practice criteria. PMID:17803820

Case-control study on uveal melanoma (RIFA: rational and design

Directory of Open Access Journals (Sweden)

Schmidt-Pokrzywniak Andrea

2004-08-01

Full Text Available Abstract Background Although a rare disease, uveal melanoma is the most common primary intraocular malignancy in adults, with an incidence rate of up to 1.0 per 100,000 persons per year in Europe. Only a few consistent risk factors have been identified for this disease. We present the study design of an ongoing incident case-control study on uveal melanoma (acronym: RIFA study that focuses on radiofrequency radiation as transmitted by radio sets and wireless telephones, occupational risk factors, phenotypical characteristics, and UV radiation. Methods/Design We conduct a case-control study to identify the role of different exposures in the development of uveal melanoma. The cases of uveal melanoma were identified at the Division of Ophthalmology, University of Essen, a referral centre for tumours of the eye. We recruit three control groups: population controls, controls sampled from those ophthalmologists who referred cases to the Division of Ophthalmology, University of Duisburg-Essen, and sibling controls. For each case the controls are matched on sex and age (five year groups, except for sibling controls. The data are collected from the study participants by short self-administered questionnaire and by telephone interview. During and at the end of the field phase, the data are quality-checked. To estimate the effect of exposures on uveal melanoma risk, we will use conditional logistic regression that accounts for the matching factors and allows to control for potential confounding.