scholarly journals Comparing different sampling methods in order to reconstruct plant economies at the Eneolithic lake dwelling site Stare gmajne, Slovenia

2016 ◽  
Vol 43 ◽  
pp. 413-420
Author(s):  
Tjaša Tolar ◽  
Anton Velušček
Keyword(s):  
Sampling Methods ◽  
Cultural Layer ◽  
Surface Sampling ◽  
Plant Macroremains ◽  
Plant Remains ◽  
Ljubljansko Barje

The results of plant macroremains studies of the Eneolithic (c. 3160–3100 cal BC) lakeshore settlement at Stare gmajne on the Ljubljansko barje in Slovenia are presented. Archaeobotanical material was collected in two different ways: (1) systematic surface sampling from the cultural layer, and (2) judgement sampling from an incompletely burnt large loom-weight. The preservation state and the spectra of plant macroremains were different in both types of samples. The first study primarily deals with the waterlogged plant remains of various types and taxa, while the second deals with carbonised and half-carbonised cereal macroremains, mostly chaff. Both studies confirm the cultivation of main crops: emmer, einkorn and barley.

scholarly journals Evaluation of Two Surface Sampling Methods for Detection of Erwinia herbicola on a Variety of Materials by Culture and Quantitative PCR

2007 ◽  
Vol 73 (11) ◽  
pp. 3505-3510 ◽  
Author(s):  
Mark P. Buttner ◽  
Patricia Cruz ◽  
Linda D. Stetzenbach ◽  
Tracy Cronin
Keyword(s):  
Quantitative Pcr ◽  
Sampling Methods ◽  
Collection Efficiency ◽  
Test Chamber ◽  
Surface Sampling ◽  
Laminate Glass ◽  
Erwinia Herbicola ◽  
Surface Samples ◽  
Sampling Protocols ◽  
Surface Materials

ABSTRACT This research was designed to evaluate surface sampling protocols for use with culture and quantitative PCR (QPCR) amplification assay for detection of the gram-negative bacterial biothreat simulant Erwinia herbicola on a variety of surface materials. Surfaces selected for evaluation were wood laminate, glass and computer monitor screens, metal file cabinets, plastic arena seats, nylon seat cushions, finished concrete flooring, and vinyl tile flooring. Laboratory and test chamber studies were performed to evaluate two sampling methods, a sponge and a macrofoam swab, for detection of E. herbicola on surface materials. In laboratory trials, seven materials were inoculated with a known concentration of E. herbicola cells and samples were collected from the surfaces of the materials to determine sampling efficiencies. Culture analysis was ineffective for assessing E. herbicola collection efficiency because very few culturable cells were obtained from surface samples. QPCR demonstrated that E. herbicola DNA was present in high concentrations on all of the surface samples, and sampling efficiencies ranged from 0.7 to 52.2%, depending on the sampling method and the surface material. The swab was generally more efficient than the sponge for collection of E. herbicola from surfaces. Test chamber trials were also performed in which E. herbicola was aerosolized into the chamber and allowed to settle onto test materials. Surface sampling results supported those obtained in laboratory trials. The results of this study demonstrate the capabilities of QPCR to enhance the detection and enumeration of biocontaminants on surface materials and provide information on the comparability of sampling methods.

A comparison of surface sampling methods for coarse fluvial sediments

1996 ◽  
Vol 32 (10) ◽  
pp. 3219-3226 ◽  
Author(s):  
Ellen E. Wohl ◽  
Deborah J. Anthony ◽  
Susan W. Madsen ◽  
Douglas M. Thompson
Keyword(s):  
Sampling Methods ◽  
Fluvial Sediments ◽  
Surface Sampling

scholarly journals Comparative evaluation of vacuum-based surface sampling methods for collection of Bacillus spores

2013 ◽  
Vol 95 (3) ◽  
pp. 389-396 ◽  
Author(s):  
M. Worth Calfee ◽  
Laura J. Rose ◽  
Stephen Morse ◽  
Dino Mattorano ◽  
Matt Clayton ◽  
...  
Keyword(s):  
Comparative Evaluation ◽  
Sampling Methods ◽  
Surface Sampling ◽  
Bacillus Spores

scholarly journals European survey and evaluation of sampling methods recommended by the standard EN ISO 18593 for the detection of Listeria monocytogenes and Pseudomonas fluorescens on industrial surfaces

2020 ◽  
Vol 367 (7) ◽  
Author(s):  
Thomas Brauge ◽  
Lena Barre ◽  
Guylaine Leleu ◽  
Stéphane André ◽  
Catherine Denis ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Pseudomonas Fluorescens ◽  
Sampling Methods ◽  
Bacterial Species ◽  
Surface Sampling ◽  
European Survey ◽  
Spoilage Bacteria ◽  
Significant Difference ◽  
Processing Plants ◽  
Survey And Evaluation

ABSTRACT The ready-to-eat products can be contaminated during processing by pathogen or spoilage bacteria, which persist in the industrial environment. Some bacterial species are able to form biofilms which protect them from environmental conditions. To check the bacterial contamination of the surfaces in the food industries, the professionals must regularly use surface sampling methods to detect the pathogen such as Listeria monocytogenes or the spoilage such as Pseudomonas fluorescens. In 2010, we designed and carried out a European survey to collect surface sampling information to detect or enumerate L. monocytogenes in food processing plants. A total of 137 questionnaires from 14 European Union Member States were returned. The outcome of this survey showed that the professionals preferred friction sampling methods with gauze pad, swab and sponges versus contact sampling methods. After this survey, we compared the effectiveness of these three friction sampling methods and the contact plates, as recommended in the standard EN ISO 18593 that was revised in 2018, on the recovery of L. monocytogenes and of P. fluorescens in mono-specie biofilms. This study showed no significant difference between the effectiveness of the four sampling methods to detach the viable and culturable bacterial population of theses mono-specie biofilms.

Adaptive Sampling Strategy for Free-Form Surface Based on CAD Model

2012 ◽  
Vol 542-543 ◽  
pp. 541-544 ◽  
Author(s):  
Gai Yun He ◽  
Hong Yang Jia ◽  
Long Zhen Guo ◽  
Pei Pei Liu
Keyword(s):  
Adaptive Sampling ◽  
Sampling Methods ◽  
Spline Interpolation ◽  
Sampling Strategy ◽  
Free Form ◽  
Digital Measurement ◽  
Cad Model ◽  
Surface Sampling ◽  
Curvature Measure ◽  
Free Form Surface

The digital measurement of free-form surface is the key to machining quality inspection for surface parts, and the basic requirement of digital measurement is how to realize the adaptive distribution of sampling points with the curvature feature. The traditional sampling methods were limited to the surface known mathematical model. This paper was concerned with free-form surface sampling with CAD model. Firstly, an algorithm of extracting data points from free-form surface was proposed, which transformed the free-from surface into intersection lines. Secondly, the B-spline interpolation was utilized to acquire the parameter expression of each line. Then the curvature measure function was defined on the basis of the curvature and the spline mass was determined taking the curvature measure as density. A new sampling method was presented based on dividing the spline mass equally. On this basis, the sampling process for surface was formulated, which realized the adaptive distribution for surface based on CAD model. The computer simulations show that the suggested method can approximate the curves and surfaces with higher precision comparing against other sampling methods.

scholarly journals Staraya Ladoga, SEM investigations of plant remains from palaeosols separated by deposits of the Ladoga transgression. New materials and old problems

2020 ◽  
Vol 30 ◽  
pp. 163-185
Author(s):  
Platonova N. ◽  
◽  
Levkovskaya G. ◽  
Britskiy D. ◽  
Kartseva L. ◽  
...  
Keyword(s):  
Cultural Layer ◽  
New Materials ◽  
Ladoga Region ◽  
Plant Remains ◽  
Lake Ilmen ◽  
Northwestern Region

This paper presents the results of SEM-examination of palynological complexes of two paleosols at the base of the Staraya Ladoga section. There was obtained evidence of the floodplain genesis of the paleosol directly under- lying the cultural layer of Zemlyanoye hillfort. A new palynological marker has been identified here which enables us to ground the synchronous character of the end of the Ladoga Transgression (in the southern Ladoga region) and the regression of Lake Ilmen (in the northwestern region).

scholarly journals Comparison of Surface Sampling Methods for Virus Recovery from Fomites

2011 ◽  
Vol 77 (19) ◽  
pp. 6918-6925 ◽  
Author(s):  
Timothy R. Julian ◽  
Francisco J. Tamayo ◽  
James O. Leckie ◽  
Alexandria B. Boehm
Keyword(s):  
Disease Transmission ◽  
Sampling Methods ◽  
Limit Of Detection ◽  
Plaque Assay ◽  
Surface Sampling ◽  
Sampling Studies ◽  
Reverse Transcription Pcr ◽  
Lack Of Information ◽  
Exposure Routes ◽  
Virus Recovery

ABSTRACTThe role of fomites in infectious disease transmission relative to other exposure routes is difficult to discern due, in part, to the lack of information on the level and distribution of virus contamination on surfaces. Comparisons of studies intending to fill this gap are difficult because multiple different sampling methods are employed and authors rarely report their method's lower limit of detection. In the present study, we compare a subset of sampling methods identified from a literature review to demonstrate that sampling method significantly influences study outcomes. We then compare a subset of methods identified from the review to determine the most efficient methods for recovering virus from surfaces in a laboratory trial using MS2 bacteriophage as a model virus. Recoveries of infective MS2 and MS2 RNA are determined using both a plaque assay and quantitative reverse transcription-PCR, respectively. We conclude that the method that most effectively recovers virus from nonporous fomites uses polyester-tipped swabs prewetted in either one-quarter-strength Ringer's solution or saline solution. This method recovers a median fraction for infective MS2 of 0.40 and for MS2 RNA of 0.07. Use of the proposed method for virus recovery in future fomite sampling studies would provide opportunities to compare findings across multiple studies.

Detection ofLegionella pneumophilain bioaerosols by polymerase chain reaction

2001 ◽  
Vol 47 (4) ◽  
pp. 341-347 ◽  
Author(s):  
Leonor Pascual ◽  
Sara Pérez-Luz ◽  
Antonio Amo ◽  
Carmen Moreno ◽  
David Apraiz ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Liquid Medium ◽  
Legionella Pneumophila ◽  
Sampling Methods ◽  
Linear Regression Analysis ◽  
Single Stage ◽  
Strong Positive Correlation ◽  
Surface Sampling ◽  
Chain Reaction ◽  
Polymerase Chain

Most studies focusing on detecting microorganisms in air by polymerase chain reaction (PCR) have used a liquid impinger to sample bioaerosols, mainly because a liquid sample is easy to be processed by PCR analysis. Nevertheless, the use of multiple-hole impactors for the analysis of bioaerosols by PCR has not been reported despite its great utility in culture analysis. In this study we have modified the impaction onto an agar surface sampling method to impaction onto a liquid medium using the MAS-100 air sampler (Merck) (single-stage multiple-hole impactor). To evaluate the recovery of airborne microorganisms of both sampling methods, a suspension containing Escherichia coli was artificially aerosolized and bioaerosols were collected onto Tergitol-7 agar and phosphate-buffered saline (PBS) with the MAS-100. A linear regression analysis of the results showed a strong positive correlation between both sampling methods (r = 0.99, slope 0.99, and y intercept 0.07). Afterwards, the method of impingement into a liquid medium was used to study airborne Legionella pneumophila by PCR. A total of 64 samples were taken at a wastewater treatment plant, a chemical plant, and an office building and analyzed by culture and PCR. Results showed that three samples were positive both by PCR and plate culture, and that nine samples negative by plate culture were positive by PCR, proving that L. pneumophila was present in bioaerosols from these three different environments. The results demonstrate the utility of this single-stage multiple-hole impactor for sampling bioaerosols, both by culture and by PCR.Key words: Legionella pneumophila, bioaerosols, PCR, multiple-hole impactor.

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