scholarly journals Development and Validation of a Simple Bioaerosol Collection Filter System Using a Conventional Vacuum Cleaner for Sampling

2021 ◽  
Author(s):  
Verena Unterwurzacher ◽  
Stephan Bruck ◽  
Max Biedermann ◽  
Clara Pogner ◽  
Anja Konlechner ◽  
...  
Keyword(s):  
Large Scale ◽  
Test Organism ◽  
Fungal Species ◽  
Antibiotics Resistance ◽  
Flow Measurements ◽  
Filter System ◽  
Biological Sampling ◽  
Biological Performance ◽  
Development And Validation ◽  
Occupational Settings

AbstractAlthough numerous bioaerosol samplers for counting and identifying airborne microorganisms are available, the considerably high purchase and maintenance costs for the sampler often prevent broad monitoring campaigns for occupational or environmental surveillance of bioaerosols. We present here a newly developed simple adapter and filter system (TOP filter system) designed to collect bioaerosol particles from a defined air volume using conventional vacuum cleaners as air pumps. We characterized the physical properties of the system using air flow measurements and validated the biological performance. The culture-based detection capacities for airborne fungal species were compared to a standard impaction sampler (MAS-100 NT) under controlled conditions in a bioaerosol chamber (using Trichoderma spores as the test organism) as well as in the field. In the chamber, an overall equivalent detection capacity between all tested filters was recorded, although a significant underrepresentation of the TOP filter system for Trichoderma spores were seen in comparison to the MAS-100 NT. In a comparative field study (n = 345), the system showed similar biological sampling efficiencies compared to the MAS-100 NT impactor, only the diversity of identified fungal communities was slightly lower on the filters. Thus, the system is suitable for large-scale environmental sampling operations where many samples have to be taken in parallel at a given time at distant locations. This system would allow endeavors such as antibiotics resistance monitoring or hygiene surveys in agricultural or occupational settings.

scholarly journals The Development of Fast Response Aerodynamic Probes for Flow Measurements in Turbomachinery

1994 ◽  
Author(s):  
Roger W. Ainsworth ◽  
John L. Allen ◽  
J. Julian M. Batt
Keyword(s):  
Mach Number ◽  
Large Scale ◽  
Flow Direction ◽  
Three Dimensional ◽  
Pressure Sensors ◽  
Fast Response ◽  
Rotor Blades ◽  
Small Scale ◽  
Hot Wire ◽  
Flow Measurements

The advent of a new generation of transient rotating turbine simulation facilities, where engine values of Reynolds and Mach number are matched simultaneously together with the relevant rotational parameters for dimensional similitude (Dunn et al [1988], Epstein et al [1984]. Ainsworth et al [1988]), has provided the stimulus for developing improved instrumentation for investigating the aerodynamic flows in these stages. Much useful work has been conducted in the past using hot-wire and laser anemometers. However, hot-wire anemometers are prone to breakage in the high pressure flows required for correct Reynolds numbers, Furthermore some laser techniques require a longer runtime than these transient facilites permit, and generally yield velocity information only, giving no data on loss production. Advances in semiconductor aerodynamic probes are beginning to fulfil this perceived need. This paper describes advances made in the design, construction, and testing of two and three dimensional fast response aerodynamic probes, where semiconductor pressure sensors are mounted directly on the surface of the probes, using techniques which have previously been successfully used on the surface of rotor blades (Ainsworth, Dietz and Nunn [1991]). These are to be used to measure Mach number and flow direction in compressible unsteady flow regimes. In the first section, a brief review is made of the sensor and associated technology which has been developed to permit a flexible design of fast response aerodynamic probe. Following this, an extensive programme of testing large scale aerodynamic models of candidate geometries for suitable semiconductor scale probes is described, and the results of these discussed. The conclusions of these experiments, conducted for turbine representative mean and unsteady flows, yielded new information for optimising the design of the small scale semiconductor probes, in terms of probe geometry, sensor placement, and aerodynamic performance. Details are given of a range of wedge and pyramid semiconductor probes constructed, and the procedures used in calibrating and making measurements with them. Differences in performance are discussed, allowing the experimenter to choose an appropriate probe for the particular measurement required. Finally, the application of prototype semiconductor probes in a transient rotor experiment at HP turbine representative conditions is described, and the data so obtained is compared with (PD solutions of the unsteady viscous flow-field.

Transpiration of Acacia plantation under managed tropical peatland in Riau, Sumatra

2021 ◽  
Author(s):  
Yogi Suardiwerianto ◽  
Sofyan Kurnianto ◽  
Adibtya Asyhari ◽  
Tubagus Muhamad Risky ◽  
Muhammad Fikky Hidayat ◽  
...  
Keyword(s):  
Transpiration Rate ◽  
Groundwater Level ◽  
Large Scale ◽  
Hydrological Modeling ◽  
Ground Surface ◽  
Terrestrial Ecosystems ◽  
Ratio Method ◽  
Flow Measurements ◽  
Groundwater Levels ◽  
Relative Contribution

<p>Transpiration is a key process in the terrestrial ecosystems linking water, carbon, and energy exchanges between the vegetation and the atmosphere. However, the understanding of transpiration rate, its spatiotemporal dynamics, and the controlling factors in tropical peatlands are still constrained by limited measurements. This study aims to investigate the transpiration rates at the stand level of Acacia plantation under different groundwater levels. The measurements were performed at two large-scale lysimeter plots with groundwater level of 40 and 80 cm below the ground surface. The transpiration rate was quantified based on sap flow measurements from 16 trees with different diameters at breast height using heat ratio method. The initial results indicate that the transpiration rate was closely correlated to the meteorological parameters, including atmospheric vapor pressure deficit and solar radiation. The two plots with different groundwater level regimes exhibit the same diurnal pattern of transpiration rate yet shows differences in their magnitude. The findings from this study will improve the understanding about relative contribution of transpiration to the total water balance under different groundwater levels. Further, an ongoing measurement of above and below-ground biomass growth and hydrological modeling work will advance the knowledge on plant-water interaction from this ecosystem.</p>

Diversified Microbial Community Developed in Different Fruit Juice of Wine Fermentation

2017 ◽  
Vol 866 ◽  
pp. 57-60 ◽  
Author(s):  
Duongruitai Nicomrat ◽  
Siriphatrc Chamutpong
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Agar Plate ◽  
Fungal Species ◽  
Wine Fermentation ◽  
Wine Production ◽  
Alcohol Production ◽  
Nutrient Sources ◽  
Fermented Broth ◽  
Grape Varieties

In the process of grape wine fermentation, it has been long known that different flavor, aroma and taste characteristics are usually from various microbes associated grape strains and grape varieties. In the study, we were interested in understanding diversity of microbial niches of fermented glutinous rice ball developed in variety of fruit wine fermentation. Since different raw materials, fruits together with different microbial consortium associated with fruit surface itself affected various dominant culturable bacterial and fungal species. In the study, freshly prepared juices of fruits; mangoes and apples after processing without the pasteurization at 65°C for 30 min revealed dissimilar pH profiles and reducing sugar contents as well as alcohol production. Under microbiological examination as well as serial dilution agar plate technique, diverse dominant bacterial and fungal isolates were detected in the wine sample of the fruits pasteurized. The nutrients originated in apple sample caused more populations of microbes, including dominant bacilli, detected in the fermented broth since they were found in apples than in mangoes (104-1013 and 104-106 cells/ mL, respectively). From the results, it was shown that different nutrient sources played more important roles in stimulation of variations in microbial assort and possibly more complex in fermented juice qualification. The understanding in microflora consortium involving in wine fermentation for each fruit type should be helpful in monitoring and reflecting the concurrent microbial activity present in the large scale of wine production, reducing the risks of existing spoilage species.

A fully distributed unstructured Navier-Stokes solver for large-scale aeroelasticity computations

2001 ◽  
Vol 105 (1050) ◽  
pp. 419-426 ◽  
Author(s):  
G. Barakos ◽  
M. Vahdati ◽  
A.I. Sayma ◽  
C. Bréard ◽  
M. Imregun
Keyword(s):  
Large Scale ◽  
Numerical Models ◽  
Navier Stokes ◽  
Multiple Data ◽  
Computational Mesh ◽  
Blade Row ◽  
Scale Modelling ◽  
Modelling Methodology ◽  
Speed Up ◽  
Development And Validation

Abstract This paper presents the development and validation of a parallel unsteady flow and aeroelasticity code for large-scale numerical models used in turbo machinery applications. The work is based on an existing unstructured Navier-Stokes solver developed over the past ten years by the Aeroelasticity Research Group at Imperial College Vibration University Technology Centre. The single-process multiple-data paradigm was adopted for the parallelisation of the solver and several validation cases were considered. The computational mesh was divided into several sub-sections using a domain decomposition technique. The performance and numerical accuracy of the parallel solver was validated across several computer platforms for various problem sizes. In cases where the solution could be obtained on a single CPU, the serial and parallel versions of the code were found to produce identical results. Studies on up to 32 CPUs showed varying levels of parallelisation efficiency, an almost linear speed-up being obtained in some cases. Finally, an industrial configuration, a 17 blade row turbine with a 47 million point mesh, was discussed to illustrate the potential of the proposed large-scale modelling methodology.

Heat Transfer Investigation of an Aggressive Intermediate Turbine Duct: Part 1—Experimental Investigation

2010 ◽  
Author(s):  
Carlos Arroyo Osso ◽  
T. Gunnar Johansson ◽  
Fredrik Wallin
Keyword(s):  
Heat Transfer ◽  
Large Scale ◽  
Computational Study ◽  
Convective Heat Transfer Coefficient ◽  
Low Pressure ◽  
Flow Measurements ◽  
Pressure Losses ◽  
Turbofan Engines ◽  
Intermediate Turbine Duct ◽  
Inlet Conditions

In most designs of two-spool turbofan engines, intermediate turbine duct (ITD’s) are used to connect the high-pressure turbine (HPT) with the low-pressure turbine (LPT). Demands for more efficient engines with reduced emissions require more “aggressive ducts”, ducts which provide both a higher radial offset and a larger area ratio in the shortest possible length, while maintaining low pressure losses and avoiding non-uniformities in the outlet flow that might affect the performance of the downstream LPT. The work presented in this paper is part of a more comprehensive experimental and computational study of the flowfield and the heat transfer in an aggressive ITD. The main objectives of the study were to obtain an understanding of the mechanisms governing the heat transfer in ITD’s and to obtain high quality experimental data for the improvement of the CFD-based design tools. This paper consists of two parts. The first one, this one, presents and discusses the results of the experimental study. In the second part, a comparison between the experimental results and a numerical analysis is presented. The duct studied was a state-of-the-art “aggressive” design with nine thick non-turning structural struts. It was tested in a large-scale low-speed experimental facility with a single-stage HPT. In this paper measurements of the steady convective heat transfer coefficient (HTC) distribution on both endwalls and on the strut for the duct design inlet conditions are presented. The heat transfer measurement technique used is based on infrared-thermography. Part of the results of the flow measurements is also included.

Mixing in Large Scale Tanks: Part I — Flow Modeling of Turbulent Mixing Jets

2004 ◽  
Author(s):  
Si Young Lee ◽  
Robert A. Dimenna ◽  
Richard A. Leishear ◽  
David B. Stefanko
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Liquid Level ◽  
Computational Results ◽  
Validation Data ◽  
Flow Measurements ◽  
Three Dimensional Representation ◽  
Lower Elevation ◽  
Tank Geometry

Flow evolution models were developed to evaluate the performance of the new advanced design mixer pump (ADMP) for sludge mixing and removal operations in one of the large-scale Savannah River Site (SRS) waste tanks, Tank 18. This paper is the first in a series of four that describe the computational model and its validation, the experiment facility and the flow measurements used to provide the validation data, the extension of the computational results to real tank conditions through the use of existing sludge suspension data, and finally, the sludge removal results from actual Tank 18 operations using the new ADMP. A computational fluid dynamics (CFD) approach was used to simulate the sludge removal operations. The models employed a three-dimensional representation of the tank with a two-equation turbulence model, since this approach was verified by both test and literature data. The discharge of the ADMP was modeled as oppositely directed hydraulic jets submerged at the center of the 85-ft diameter tank, with pump suction taken from below. The calculations were based on prototypic tank geometry and nominal operating conditions. In the analysis, the magnitude of the local velocity was used as a measure of slurrying and suspension capability. The computational results showed that normal operations in Tank 18 with the ADMP mixer and a 70-in liquid level would provide adequate sludge removal in most regions of the tank. The exception was the region within about 1.2 ft of the tank wall, based on an historical minimum velocity required to suspend sludge. Sensitivity results showed that a higher tank liquid level and a lower elevation of pump nozzle would result in better performance in suspending and removing the sludge. These results were consistent with experimental observations.

The Development and Validation of a Teacher Belief Survey for the Constructivist Classroom

2020 ◽  
pp. 105678792093989
Author(s):  
Monika A. von Oppell ◽  
Jill M. Aldridge
Keyword(s):  
Education Reform ◽  
Student Teachers ◽  
United Arab Emirates ◽  
Classroom Practice ◽  
Large Scale ◽  
Face Validity ◽  
Teacher Belief ◽  
Teachers Beliefs ◽  
Teacher Belief Survey ◽  
Development And Validation

The research reported in this article was part of a larger study which took place in Abu Dhabi, United Arab Emirates. The large-scale education reform, being carried out at the time of the study, required paradigm shifts in practice; from a traditional to a constructivist approach. The education reform posed on-going challenges and posed questions regarding the future impact for teachers, particularly with respect to their beliefs with respect to classroom practice. This article describes the development and validation of a survey to assess teachers’ beliefs in this new context. The survey assesses teachers’ beliefs about their role in the classroom and philosophy of teaching and learning and their classroom practice. The translation validity of the survey was supported by examining the content and face validity. Further, analysis of the data collected 182 Arab teachers was used to provide support for the reliability and validity of the newly developed Teacher Belief Survey in terms of factor structure, internal consistency reliability, discriminant and concurrent validity. This instrument has the potential to be useful for ascertaining teachers’ professional development needs and for understanding the beliefs of student teachers. In regions of cross-cultural diversity the findings may assist in creating understanding and sensitivity of the cultural differences between people, their knowledge, perspectives and practices.

scholarly journals Development and Validation of a Short-Form Internet Overuse Screening Questionnaire for Adults

2020 ◽  
Vol 26 (6) ◽  
pp. 335-345
Author(s):  
Soowon Park ◽  
Seungchan Lee ◽  
Boungho Choi ◽  
Seunghee Cho ◽  
Jin-Pyo Hong ◽  
...  
Keyword(s):  
Large Scale ◽  
Latent Class ◽  
Short Form ◽  
Cutoff Score ◽  
Screening Questionnaire ◽  
Receiver Operating Characteristic Curves ◽  
Internet Users ◽  
Large Scale Survey ◽  
Development And Validation ◽  
Selection Of

<b><i>Aims:</i></b> The aim of the current study was to develop and validate a short-form of the internet overuse screening questionnaire (IOS-Qs). <b><i>Methods:</i></b> A total of 571 adults were recruited from a representative, stratified, and multistage cluster sample. Among participants, 188 and 383 were used in the development and validation of the IOS-Qs, respectively. <b><i>Results:</i></b> Experts’ ratings and Rasch model analyses led to the selection of 8 items from the IOS-Qs; latent-class analysis using these 8 items revealed an estimated prevalence of 8.6% (33 out of 383) of problematic internet over-users. Problematic internet over-users were positively associated with a 1-year prevalence rate of any mental disorder (OR 3.08, <i>p</i> = 0.008), mood disorder (OR 7.11, <i>p</i> = 0.003), and depressive disorder (OR 5.22, <i>p</i> = 0.016). The receiver operating characteristic curves identified an optimal cutoff score of 9.5 for differentiating problematic internet over-users from unproblematic internet users with 94% sensitivity and 94% specificity. <b><i>Conclusion:</i></b> The results suggest that the IOS-Qs was valid, and items including social isolation were crucial to the brief distinction of at-risk internet users. Because of its brevity, the questionnaire can be effectively administered as a large-scale survey.

scholarly journals Genome-Wide Novel Genic Microsatellite Marker Resource Development and Validation for Genetic Diversity and Population Structure Analysis of Banana

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1479
Author(s):  
Manosh Kumar Biswas ◽  
Mita Bagchi ◽  
Dhiman Biswas ◽  
Jennifer Ann Harikrishna ◽  
Yuxuan Liu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Ssr Markers ◽  
Comparative Mapping ◽  
In Silico ◽  
Large Scale ◽  
Crop Improvement ◽  
Musa Spp ◽  
Population Structure Analysis ◽  
A Genome ◽  
Development And Validation

Trait tagging through molecular markers is an important molecular breeding tool for crop improvement. SSR markers encoded by functionally relevant parts of a genome are well suited for this task because they may be directly related to traits. However, a limited number of these markers are known for Musa spp. Here, we report 35136 novel functionally relevant SSR markers (FRSMs). Among these, 17,561, 15,373 and 16,286 FRSMs were mapped in-silico to the genomes of Musa acuminata, M. balbisiana and M. schizocarpa, respectively. A set of 273 markers was validated using eight accessions of Musa spp., from which 259 markers (95%) produced a PCR product of the expected size and 203 (74%) were polymorphic. In-silico comparative mapping of FRSMs onto Musa and related species indicated sequence-based orthology and synteny relationships among the chromosomes of Musa and other plant species. Fifteen FRSMs were used to estimate the phylogenetic relationships among 50 banana accessions, and the results revealed that all banana accessions group into two major clusters according to their genomic background. Here, we report the first large-scale development and characterization of functionally relevant Musa SSR markers. We demonstrate their utility for germplasm characterization, genetic diversity studies, and comparative mapping in Musa spp. and other monocot species. The sequences for these novel markers are freely available via a searchable web interface called Musa Marker Database.

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