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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Comparing Measures of the Concentration of Crime at Places and Times

Lee, YongJei 12 December 2017 (has links)
No description available.
262

Mätningar av koldioxid- och metankoncentrationer över skogsbestånd med mobila mätsystem - en litteratur- och surveystudie för att kartlägga dagens teknikutveckling och framtidsutsikter / Measurements of carbon dioxide and methane flows over forest stands with mobile measuring systems - a literature- and survey study to map todays technology development and future prospects

Neuman, Malin January 2021 (has links)
Mänsklig aktivitet har ökat utsläppen av växthusgaser i atmosfären så mycket att det påverkat klimatet och spås förändra det mer om inte åtgärder vidtas för att utsläppen ska minksa och helst upphöra helt. För att lindra effekterna av koldioxid, som är den växthusgas med störst påverkan, kan skogen spela en stor roll. För att veta vilka åtgärder som är lämpliga krävs förståelse för hur olika ingrepp i skogen påverkar dess upptag och utsläpp. Under några decennier har koncentrationer och flöden av växthusgaser mätts med hjälp av fasta master. De är dock för få för att kunna generalisera resultaten över hela landskap. Här undersöks hur teknikläget för mobila mätmetoder ser ut idag via en litteratur- och surveyundersökning. Samtliga respondenter är hoppfulla och tror att det bara är en tidsfråga innan tekniken finns för att kunna använda sig av små drönare för att kunna genomföra mätningar av gaser över skogsmark. Ett koncept för en pilotstudie har tagits fram där koldioxidkoncentrationer ska mätas.
263

A COMPARISON OF TWO COMMERCIAL STRIPS WITH PREDEFINED ANTIBIOTIC CONCENTRATION GRADIENTS FOR SUSCEPTIBILITY TESTING OF PERIODONTAL BACTERIAL PATHOGENS

Bui, Hanh January 2013 (has links)
Objectives: Systemic antibiotics are generally recognized as providing a beneficial impact in treatment of both aggressive and chronic periodontitis. Since strains of periodontal pathogens among periodontitis patients may vary in their antibiotic drug resistance, the American Academy of Periodontology recommends antimicrobial susceptibility testing of suspected periodontal pathogens prior to administration of systemic periodontal antibiotic therapy, to reduce the risk of a treatment failure due to pathogen antibiotic resistance. E-test and MIC Test Strip assays are two in vitro antimicrobial susceptibility testing systems employing plastic- and paper-based, respectively, carriers loaded with predefined antibiotic gradients covering 15 two-fold dilutions. To date, no performance evaluations have been carried out comparing the Etest and MIC Test Strip assays in their ability to assess the in vitro antimicrobial susceptibility of periodontal bacterial pathogens. As a result, the purpose of this study was to compare the in vitro performance of E-test and MIC Test Strip assays in assessing minimal inhibitory concentration (MIC) values of four antibiotics frequently utilized in systemic periodontal antibiotic therapy against 11 fresh clinical subgingival isolates of the putative periodontal pathogen, Prevotella intermedia/ nigrescens, and to compare the distribution of P. intermedia/ nigrescens strains identified with interpretative criteria as "susceptible" and "resistant" to each of the four antibiotics using MIC values determined by the two antimicrobial susceptibility testing methods. Methods: Standardized cell suspensions, equivalent to a 2.0 McFarland turbidity standard, were prepared with 11 fresh clinical isolates of P. intermedia/nigrescens, each recovered from the subgingival microbiota of United States chronic periodontitis subjects, and plated onto to the surfaces of culture plates containing enriched Brucella blood agar. After drying, pairs of antibiotic-impregnated, quantitative, gradient diffusion strips from two manufacturers (E-test, bioMérieux, Durham, NC, USA, and MIC Test Strip, Liofilchem s.r.l., Roseto degli Abruzzi, Italy) for amoxicillin, clindamycin, metronidazole, and doxycycline were each placed apart from each other onto the inoculated enriched Brucella blood agar surfaces, so that an antibiotic test strip from each manufacturer was employed per plate against each P. intermedia/ nigrescens clinical isolate for antibiotic susceptibility testing. After 48-72 hours anaerobic jar incubation, individual MIC values for each antibiotic test strip against P. intermedia/nigrescens were read in μg/ml at the point where the edge of the bacterial inhibition ellipse intersected with the antibiotic test strip. MIC50, MIC90, and MIC range were calculated and compared for each of the test antibiotics, with essential agreement (EA) values determined per test antibiotic for the level of outcome agreement between two antimicrobial susceptibility testing methods. In addition, the identification of antibiotic "susceptible" and "resistant" strains among the P. intermedia/nigrescens clinical isolates was determined for each test antibiotic using MIC interpretative criteria from the MIC interpretative standards developed by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) for gram-negative anaerobic bacteria for amoxicillin, clindamycin, and metronidazole findings, and from the French Society of Microbiology breakpoint values for anaerobic disk diffusion testing for doxycycline data. Results: For amoxicillin, higher MIC50 and MIC90 values against the P. intermedia/ nigrescens strains were found with the MIC Test Strip assay than with E-test strips, resulting in a relatively low EA value of 45.5% between the two susceptibility testing methods. A higher percentage of amoxicillin "resistant" P. intermedia/nigrescens strains (72.7%) were identified by MIC Test Strips as compared to E-test strips (54.5%), although both methods found the same proportion of amoxicillin "susceptible" strains (27.3%). For clindamycin, both susceptibility testing methods provided identical MIC values (EA value = 100%), and exactly the same distributions of "susceptible" and "resistant" strains of P. intermedia/nigrescens. For metronidazole, only very poor agreement (EA value = 9.1%) was found between the two susceptibility testing methods, with MIC Test Strips exhibiting markedly higher MIC50 and MIC90 values against P. intermedia/nigrescens as compared to E-test strips. However, the distribution of "susceptible" and "resistant" P. intermedia/ nigrescens were identical between the two susceptibility testing methods. For doxycycline, relatively good agreement (EA value = 72.7%) was found in MIC concentrations between the two susceptibility testing methods, although generally lower MIC values were associated with MIC Test Strips. In addition, identical distributions of "susceptible" and "resistant" P. intermedia/nigrescens were provided by both susceptibility testing methods. Conclusions: Relative to MIC values measured against periodontal strains of P. intermedia/nigrescens, MIC Test Strips gave higher MIC values with amoxicillin and metronidazole, equal MIC values with clindamycin, and lower MIC values with doxycycline, as compared to MIC values measured with the E-test assay. Relative to the identification of antibiotic "susceptible" periodontal P. intermedia/ nigrescens strains, both susceptibility testing methods provided identical findings, suggesting that both methods appear to be interchangeable for clinical decision making in regard to identification of antibiotic-sensitive strains of periodontal P. intermedia/nigrescens. However, for epidemiologic surveillance of drug susceptibility trends, where exact MIC values are important to track over time, the relatively higher proportion of non-exact MIC differences between the two susceptibility testing methods argues against using them interchangeably. Instead, one or the other method should be used consistently for such studies. Further comparative studies of the E-test and MIC Test Strip assays are indicated using other periodontopathic bacterial species besides P. intermedia/ nigrescens, and to assess the reproducibility of MIC values provided by both in vitro susceptibility testing methods over time. / Oral Biology
264

Review of Suspended Sediment Transport Mathematical Modelling Studies

Wallwork, J.T., Pu, Jaan H., Kundu, S., Hanmaiahgari, P.R., Pandey, M., Satyanaga, A., Khan, M.A., Wood, Alistair S. 23 March 2022 (has links)
Yes / This paper reviews existing studies relating to the assessment of sediment concentration profiles within various flow conditions due to their importance in representing pollutant propagation. The effects of sediment particle size, flow depth, and velocity were considered, as well as the eddy viscosity and Rouse number influence on the drag of the particle. It is also widely considered that there is a minimum threshold velocity required to increase sediment concentration within a flow above the washload. The bursting effect has also been investigated within this review, in which it presents the mechanism for sediment to be entrained within the flow at low average velocities. A review of the existing state-of-the-art literature has shown there are many variables to consider, i.e., particle density, flow velocity, and turbulence, when assessing the suspended sediment characteristics within flow; this outcome further evidences the complexity of suspended sediment transport modelling.
265

Synthesis, Characterization, Critical Micelle Concentration and Antimicrobial Activity of Two-headed Amphiphiles

Maisuria, Bhadreshkumar B. 15 September 2009 (has links)
This project is about the synthesis of homologous series of two-headed, long-chain amphiphiles (the 2CCbn series, where n = 16, 18, 20, 22, 30, 5α-cholestan-3Ã -ol). The 2CCbn series was synthesized in five steps. The first step involves a reaction of nitroethane and two equivalents of tert-butyl acrylate to form nitrodiester by successive Michael addition reaction. The second step is the reduction of nitrodiester with Raney nickel to form aminodiester. The third step involves a reaction of aminodiester with di-tert-butyl dicarbonate [(Boc)2O] to form isocyanatediester. The fourth step is addition of iscocyanatediester with aliphatic alcohol to give alkyl carbamate diester (2ECbn) series. The fifth step is the removal of the tert-butyl protecting group to give the 2CCbn series. The critical micelle concentrations (CMC) were measured by the pyrene-based fluorescent probe method. The pyrene excited at 345 nm and fluoresces with maxima at 374 nm (I1) and 385 nm (I3). The stock solution and the dilution series for each amphiphiles were made in 0.9% triethanolamine solution. The CMCs were measured at two pH ~9.2 and 7.4. The CMCs were determined by plotting I1/I3 vs. concentrations. The CMCs were decreasing with increasing chain length. The CMCs for the 2CCbn series are lower than the 3CCbn series but higher than the fatty acids. The minimal inhibitory concentrations were measured against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. These strains were grown on BHIB+S with 5% triethanolamine. The MICs of the 2CCbn series amphiphiles were measured by using microtiter plate reader and by looking turbidity. The cutoff effect was found for the 2CCbn series. The MIC decreased up to C20 chain length and started rising for C22. The 2CCb18 (MICâ 2.2 µg/mL) of the 2CCbn series was the most effective amphiphile against S. aureus and MRSA. The CMC/MIC ratio was used to determine the safety of an amphiphile as a drug use. The amphiphile 2CCb18 has given the largest safety ratio (CMC/MIC = 273) against S. aureus and MRSA. It suggests that micelle formation is not a mechanism of action for anti-Staphylococcal activity. / Master of Science
266

The friction effect in the flaw distribution determination by the hardness indentation test.

Chiu, Paul Tsan-Tin. January 1978 (has links)
Thesis: M.S., Massachusetts Institute of Technology, Department of Mechanical Engineering, 1978 / Bibliography: leaves 25-27. / M.S. / M.S. Massachusetts Institute of Technology, Department of Mechanical Engineering
267

Koncentrace v soudním řízení / Concentration in civil proceedings

Kubešová, Silvia January 2012 (has links)
1 Abstract The dissertation focused its attention on the principle of the concentration and its application in civil proceedings. The principle of the concentration and its issues represented after the amendment of Civil Procedure Code No. 99/1963 realized by Act No. 30/2000 Sb. and the by Act No. 7/2009 Sb. are highly actual topic in the civil practice and in the theory of civil procedure. The dissertation attempts to explain the positives and the negatives of the principle of the concentration in civil proceedings, seeks and finds its adequate place in the civil procedural law in order to achieve an effective and quick protection of endangered or infringed subjective private rights. The theoretical basis of the dissertation consists of definition of the essence of the principle of the concentration, its object and mainly its purpose along in the system of the principles regulating civil proceedings at all. The modern civil proceedings should be based on the principle of the concentration in order to ensure the effective protection of endangered or infringed subjective private rights provided by the courts. The individual elements and phases of applying the principle of the concentration in civil proceedings should be appropriately chosen in civil proceedings. The individual elements of the principle of...
268

Der Regensburger SS-Zahnarzt Dr. Willy Frank /

Huber, Barbara. January 1900 (has links)
Zugl.: Regensburg, Univ., Diss. / Includes bibliographical references (p. 158-164).
269

Victims of Hope: Explaining Jewish Behavior in the Treblinka, Sobibór and Birkenau Extermination Camps

Motl, Kevin C. 08 1900 (has links)
I analyze the behavior of Jews imprisoned in the Treblinka, Sobibór, and Birkenau extermination camps in order to illustrate a systematic process of deception and psychological conditioning, which the Nazis employed during World War II to preclude Jewish resistance to the Final Solution. In Chapter I, I present resistance historiography as it has developed since the end of the war. In Chapter II, I delineate my own argument on Jewish behavior during the Final Solution, limiting my definition of resistance and the applicability of my thesis to behavior in the extermination camp, or closed, environment. In Chapters III, IV, and V, I present a detailed narrative of the Treblinka, Sobibór, and Birkenau revolts using secondary sources and selected survivor testimony. Finally, in Chapter VI, I isolate select parts of the previous narratives and apply my argument to demonstrate its validity as an explanation for Jewish behavior.
270

Flood Suspended Sediment Transport: Combined Modelling from Dilute to Hyper-concentrated Flow

Pu, Jaan H., Wallwork, Joseph T., Khan, M.A., Pandey, M., Pourshahbaz, H., Satyanaga, A., Hanmaiahgari, P.R., Gough, Timothy D. 15 February 2021 (has links)
Yes / During flooding, the suspended sediment transport usually experiences a wide-range of dilute to hyper-concentrated suspended sediment transport depending on the local flow and ground con-ditions. This paper assesses the distribution of sediment for a variety of hyper-concentrated and dilute flows. Due to the differences between hyper-concentrated and dilute flows, a linear-power coupled model is proposed to integrate these considerations. A parameterised method combining the sediment size, Rouse number, mean concentration, and flow depth parameters has been used for modelling the sediment profile. The accuracy of the proposed model has been verified against the reported laboratory measurements and comparison with other published analytical methods. The proposed method has been shown to effectively compute the concentration profile for a wide range of suspended sediment conditions from hyper-concentrated to dilute flows. Detailed com-parisons reveal that the proposed model calculates the dilute profile with good correspondence to the measured data and other modelling results from literature. For the hyper-concentrated profile, a clear division of lower (bed-load) to upper layer (suspended-load) transport can be observed in the measured data. Using the proposed model, the transitional point from this lower to upper layer transport can be calculated precisely.

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