scholarly journals Water Permeability of Pervious Concrete Is Dependent on the Applied Pressure and Testing Methods

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yinghong Qin ◽  
Haifeng Yang ◽  
Zhiheng Deng ◽  
Jiang He
Keyword(s):  
Water Permeability ◽  
Applied Pressure ◽  
Pervious Concrete ◽  
Testing Methods ◽  
Applied Water ◽  
Apparent Permeability ◽  
Testing Method ◽  
Water Head ◽  
Constant Head ◽  
Constant Head Method

Falling head method (FHM) and constant head method (CHM) are, respectively, used to test the water permeability of permeable concrete, using different water heads on the testing samples. The results indicate the apparent permeability of pervious concrete decreasing with the applied water head. The results also demonstrate the permeability measured from the FHM is lower than that from the CHM. The fundamental difference between the CHM and FHM is examined from the theory of fluid flowing through porous media. The testing results suggest that the water permeability of permeable concrete should be reported with the applied pressure and the associated testing method.

scholarly journals 9. Evaluation of Synergy Testing Methods for Clinical Labs to Determine Susceptibility of Extensively Drug-resistant Gram-negatives to Ceftazidime/ Avibactam and Aztreonam Combination Therapy

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S5-S6
Author(s):  
Ayesha Khan ◽  
Samuel G Erickson ◽  
Cedric H Pettaway ◽  
Cesar A Arias ◽  
William R Miller ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Clinical Decision Making ◽  
Research Study ◽  
Scientific Research ◽  
Major Error ◽  
Testing Methods ◽  
Research Support ◽  
Testing Method ◽  
Study Investigator ◽  
Synergy Testing

Abstract Background Carbapenem-resistant Enterobacterales (CRE) and Pseudomonas aeruginosa (CR-PA) producing Metallo-β-lactamases (MBLs) cause severe nosocomial infections with no defined treatment. Combination therapy with ceftazidime/ avibactam (CZA) and aztreonam (ATM) is a potential option, but there is no approved, feasible, synergy testing method for clinical labs to guide clinical decision making. Here, we evaluate the performance of 4 synergy testing methods using gradient-strips or disks. Methods We used 10 representative Enterobacterales strains, namely, E. coli, K. pneumoniae, and E. cloacea, and 6 PA strains harboring MBL, GES or non-MBL enzymes (Fig 1). 4 strains were successfully treated with CZA-ATM in case reports, the rest were from the CDC AR Bank. Four synergy testing methods were evaluated, i) Disk stack (DS), ii) Disk elution (DE), iii) Gradient-strip Stack (SS), iv) Gradient-strip Cross (SX) (Fig 1). All methods were run side-by-side as per CLSI guidelines with broth microdilution (BMD) as the reference. Data is the mean of 3 replicates. Synergy is defined as a strain that is resistant (R) to ATM but drops to ≤ the susceptible (S) breakpoint (Table 1) in the presence of CZA (Fig 2). Categorical agreement (CA), very major error (VME), major error (ME), minor error (MI) were calculated across methods for CZA-ATM synergy relative to BMD. Summary of synergy testing methods evaluated CLSI Breakpoints used for this study Results All CRE with NDM and PA with GES were ATM-R, CZA-R and S to the CZA-ATM combination. PA with NDM or VIM remained R to CZA-ATM likely due to other mechanisms of resistance. CA was high for DE (100%), SS (81%, MI 19%), and SX (88%, MI 13%) but low for DS (25%, ME 54%, MI 31%). Representative strains are shown (Fig 2, Table 2). Removing PA, CA for DE, SS, and SX was 100% and 20% for DS. Representative results of strains with each synergy testing method. Representative data of strains displaying synergy (green) or no synergy (red) Conclusion Overall, DE was the most reliable method for CZA-ATM synergy testing, and could be a valuable tool in low-resource labs. SS and SX were reliable but prone to technical error. DS had the worst performance. Disks and gradient-strips had identical performance across brands. We propose an algorithm for ATM-R, CZA-R, and MBL-positive CRE, where CZA-ATM synergy testing may be beneficial to guide therapy. These methods are reliable qualitative indicators of the presence or absence of synergy. Synergy testing is not recommended for CR-PA due to complex resistance profiles. Disclosures Cesar A. Arias, M.D., MSc, Ph.D., FIDSA, Entasis Therapeutics (Scientific Research Study Investigator)MeMed (Scientific Research Study Investigator)Merck (Grant/Research Support) William R. Miller, MD, Entasis Therapeutics (Scientific Research Study Investigator)Merck (Grant/Research Support)Shionogi (Advisor or Review Panel member)

scholarly journals Orthogonal Analysis of Water Permeability of Pervious Concrete

2014 ◽  
Vol 26 (6) ◽  
pp. 1811-1815 ◽  
Author(s):  
Zhongyuan Li ◽  
Jie Yang ◽  
Shaobo Li ◽  
Xinyi Xu ◽  
Hanzhi Song
Keyword(s):  
Water Permeability ◽  
Pervious Concrete ◽  
Orthogonal Analysis

scholarly journals Seed viability of common ragweed (Ambrosia artemisiifolia L.) is affected by seed origin and age, but also by testing method and laboratory

NeoBiota ◽  
2021 ◽  
Vol 70 ◽  
pp. 193-221
Author(s):  
Rea Maria Hall ◽  
Bernhard Urban ◽  
Hana Skalova ◽  
Lenka Moravcová ◽  
Ulrike Sölter ◽  
...  
Keyword(s):  
Seed Viability ◽  
Ambrosia Artemisiifolia ◽  
Testing Methods ◽  
Triphenyltetrazolium Chloride ◽  
Viability Test ◽  
Common Ragweed ◽  
Testing Procedures ◽  
Testing Method ◽  
Seed Origin ◽  
Set Up

Common ragweed (Ambrosia artemisiifolia L.) is an annual Asteraceae species native to North America which is highly invasive across Europe and has harmful impacts, especially on human health and agriculture. Besides its wide ecological range, particularly its high reproductive power by seeds is promoting its spread to various habitats and regions. To prevent further spread and to control the plant, the European Commission funded projects and COST-Actions involving scientists from all over Europe. A joint trial was set up comprising eight different laboratories from Europe to study seed viability variation in different seed samples. Three different testing methods (viability test with 2,3,5-triphenyltetrazolium chloride (TTC), a germination test combined with a subsequent TTC test and a crush test) were tested within the EU-COST-Action SMARTER network to four different seed origins. The viability test results from different laboratories were compared for variation amongst tests and laboratories. The main aim was to optimise the reliability of testing procedures, but results revealed not only significant effects of seed origin and seed age on seed viability, but also considerable differences between the output of the individual testing methods and furthermore between laboratories. Due to these significant differences in the results of the testing labs, additionally a second test was set up. Twelve Austrian ragweed populations were used for TTC testing to obtain a precise adjustment of the testing method as well as a tight guideline for interpreting the results, particularly for the TTC state “intermediate” since a proper classification of TTC-intermediate coloured seeds is still a challenge when determining viability rates.

scholarly journals Research on the Computer Software Testing Method Based on Multiple Platforms

2020 ◽  
Vol 2 (3) ◽  
Author(s):  
Yongfang Sun ◽  
Jianjun Li
Keyword(s):  
Software Development ◽  
Software Testing ◽  
Computer Software ◽  
Test Accuracy ◽  
Testing Methods ◽  
Modern Life ◽  
Testing Method ◽  
Software Companies ◽  
And Control

Informationization plays an important role in modern life and production. And various software is one of the bases for it. Before it goes into service, software needs to go through many steps, including software development, design, etc. In software development, test is the key to identify and control bugs and errors in the software. Therefore, software companies often test the software to ensure that it is qualified. In recent years, more attention has been paid to a multi-platform computer software testing method, which can make up for defects in traditional testing methods to improve test accuracy. Firstly, this paper illustrates the connotation and features of software testing. Secondly, common software testing platforms and their requirements are analyzed. Finally, this paper proposes software testing method based on multiple platforms.

scholarly journals Metamorphic Testing Integer Overflow Faults of Mission Critical Program: A Case Study

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Zhanwei Hui ◽  
Song Huang ◽  
Zhengping Ren ◽  
Yi Yao
Keyword(s):  
Collision Avoidance ◽  
Traditional Method ◽  
Property Testing ◽  
Testing Methods ◽  
Metamorphic Testing ◽  
Testing Method ◽  
Safety Property ◽  
Mission Critical ◽  
Collision Avoidance System

For mission critical programs, integer overflow is one of the most dangerous faults. Different testing methods provide several effective ways to detect the defect. However, it is hard to validate the testing outputs, because the oracle of testing is not always available or too expensive to get, unless the program throws an exception obviously. In the present study, the authors conduct a case study, where the authors apply a metamorphic testing (MT) method to detect the integer overflow defect and alleviate the oracle problem in testing critical program of Traffic Collision Avoidance System (TCAS). Experimental results show that, in revealing typical integer mutations, compared with traditional safety property testing method, MT with a novel symbolic metamorphic relation is more effective than the traditional method in some cases.

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