Search results for "Peat"
showing 10 items of 1026 documents
Gas chromatographic determination of organochlorine pesticides in cow milk.
2004
A gas chromatographic method of use in determining the following organochlorine pesticides in cow milk has been adapted and validated: alpha-hexachlorocyclohexane (alpha-HCH), beta-HCH, lindane, delta-HCH, hexachlorobenzene, aldrin, heptachlor, heptachlor epoxide, mirex, 2,4-dichlorodiphenyltrichloroethane (2,4-DDT), 4,4-DDT, 2,4-dichlorodiphenyldichloroethane (2,4-DDD), 4,4-DDD, 2,4-dichlorodiphenylethane (2,4-DDE) and 4,4-DDE. The method studied consists of three steps: the extraction of fat by centrifugation, mixing with anhydrous sodium sulfate, and transfer to a glass column and elution with hexane; purification of the extract via concentrated sulfuric acid treatment; and determination…
Formal verification of a Cooperative Automatic Repeat reQuest MAC protocol
2012
Author's version of an article published in the journal: Computer Standards & Interfaces. Also available from the publisher at: http://dx.doi.org/10.1016/j.csi.2011.12.001 Cooperative communications, in which a relay node helps the source node to deliver its packets to the destination node, are able to obtain significant benefits in terms of transmission reliability, coverage extension and energy efficiency. A Cooperative Automatic Repeat reQuest (C-ARQ) MAC protocol has been recently proposed to exploit cooperative diversity at the MAC layer. in this paper, we validate the integrity and the validity of the C-ARQ protocol using formal methods. The protocol logic is modeled in SDL and implem…
The Gypsy Database (GyDB) of mobile genetic elements.
2007
In this article, we introduce the Gypsy Database (GyDB) of mobile genetic elements, an in-progress database devoted to the non-redundant analysis and evolutionary-based classification of mobile genetic elements. In this first version, we contemplate eukaryotic Ty3/Gypsy and Retroviridae long terminal repeats (LTR) retroelements. Phylogenetic analyses based on the gag-pro-pol internal region commonly presented by these two groups strongly support a certain number of previously described Ty3/Gypsy lineages originally reported from reverse-transcriptase (RT) analyses. Vertebrate retroviruses (Retroviridae) are also constituted in several monophyletic groups consistent with genera proposed by t…
Assessment of Osstell ISQ's reliability for implant stability measurement: a cross-sectional clinical study
2013
Resonance frequency analysis (RFA) allows assess implant stability by measuring implant oscillation frequency on the bone. RFA is an objective and non-invasive method for implant stability measurement, although scarce evidence has been provided so far on its reliability. Objectives: Assess the Osstell ISQ system's reliability (i.e., its measurement reproducibility and repeatability) by means of the intraclass correlation coefficient (ICC) as statistical method. Study Desing: Implants stability registers were completed by means of Osstell ISQ on 85 implants on 23 patients. Six measurements were completed on each implant by means of two different SmartPegs (types I and II); that is, three con…
Intra‐ and inter‐instrument reliability of the Actiwatch 4 accelerometer in a mechanical laboratory setting.
2012
Intra- and Inter-Instrument Reliability of the Actiwatch 4 Accelerometer in a Mechanical Laboratory Setting This study aimed to quantify the intra-and inter-instrument reliability of the Actiwatch 4 accelerometer (AW4) in a mechanical setting. Twenty seven AW4 were attached to an isokinetic dynamometer and subjected to angular acceleration for 30 min at 50 deg/sec representing moderate intensity (MPA condition) and 200 deg/sec representing vigorous intensity (VPA condition), with a repeat trial conducted. Reliability was assessed using coefficient of variation (CV), absolute percent error (APE), and intraclass correlation coefficients (ICC). Mean AW4 activity counts displayed acceptable rel…
Structure and evolution of the leucine plasmids carried by the endosymbiont (Buchnera aphidicola) from aphids of the family Aphididae.
1998
In all examined species of the family Aphididae, the bacterial endosymbiont Buchnera aphidicola carries a plasmid encoding the genes leuABCD (involved in leucine biosynthesis) along with repA1, repA2 and ORF1. The gene organisation of the leucine plasmids was conserved, except in Buchnera isolated from Pterocomma populeum, where ORF1 was located in a different position. An inverted repeat (LIR1) located between repA2 and leuA is found in all of the Buchnera leucine plasmids examined. The predicted secondary structure of the LIR1 transcript conforms to a long hairpin loop, suggesting an involvement in transcription termination or messenger stability. Phylogenetic reconstruction based on repA…
A region on human chromosome 4 (q35.1→qter) induces senescence in cell hybrids and is involved in cervical carcinogenesis
2005
Human papillomavirus (HPV) types 16 and 18 are known to play a major role in cervical carcinogenesis. Additional genetic alterations are required for the development and progression of cervical cancer. Previously, we showed that the introduction of an entire human chromosome 4 into HPV-immortalized cells by microcell-mediated chromosome transfer (MMCT) can induce senescence in cell hybrids. In the present study, we established eight new murine donor cell lines harboring different fragments of the human chromosome 4. These were tested for their ability to induce senescence by MMCT into HPV16-immortalized keratinocytes (HPK II) and cervical carcinoma cells (HeLa). By exclusion, we could ident…
Qualitative Longitudinal Research in Health Research: A Method Study
2022
Abstract Background Qualitative longitudinal research (QLR) comprises qualitative studies, with repeated data collection, that focus on the temporality (e.g., time and change) of a phenomenon. The use of QLR is increasing in health research since many topics within health involve change (e.g., progressive illness, rehabilitation). A method study can provide an insightful understanding of the use, trends and variations within this approach. The aim of this study was to map how QLR articles within the existing health research literature are designed to capture aspects of time and/or change. Methods This method study used an adapted scoping review design. Articles were eligible if they were wr…
Comparison of two melting range analysis methods with lactitol monohydrate
2001
Abstract In pharmacopoeia, the melting point is determined by a standard method with a melting point instrument. The melting point can also be determined with differential scanning calorimetry (DSC). In this study, the standard method and DSC method are compared for determining the melting range of lactitol monohydrate. The effect of initial temperature, grinding, and drying on the melting range of different lactitol monohydrate samples was studied by a melting point instrument. The melting point and melting enthalpy of the stable form of lactitol monohydrate was identified by DSC. The statistical analysis of the results is based on a t-test. All studied variables had a small effect on the …
Poly(alkoxyphenylene-thienylene) Langmuir-Schäfer thin-films for advanced performance transistors
2005
Solution processed Langmuir-Scha ̈fer and cast thin films of regioregular poly(2,5-dioctyloxy-1,4- phenylene-alt-2,5-thienylene) are investigated as transistor active layers. The study of their field-effect properties evidences that no transistor behavior can be seen with a cast film channel material. This was not surprising considering the twisted conformation of the polymer backbone predicted by various theoretical studies. Strikingly, the Langmuir-Scha ̈fer (LS) thin films exhibit a field-effect mobility of 5 × 10-4 cm2/V‚s, the highest attained so far with an alkoxy-substituted conjugated polymer. Extensive optical, morphological, and structural thin-film characterization supports the a…