The role of moisture cycling in the weathering of a quartz chlorite schist in a tropical environment: findings of a laboratory simulation

2005 ◽  
Vol 30 (4) ◽  
pp. 413-428 ◽  
Author(s):  
Tony Wells ◽  
Philip Binning ◽  
Garry Willgoose
Keyword(s):  
Tropical Environment ◽  
Laboratory Simulation ◽  
Moisture Cycling ◽  
Chlorite Schist

Study on the Influence of Freeze-Thaw on the Carbonation Property of Fly Ash Concrete

2013 ◽  
Vol 357-360 ◽  
pp. 939-943 ◽  
Author(s):  
Jian Gang Niu ◽  
Liang Yan ◽  
Hai Tao Zhai
Keyword(s):  
Fly Ash ◽  
Laboratory Simulation ◽  
Influence Coefficient ◽  
Carbonation Depth ◽  
Freeze Thaw ◽  
Fly Ash Concrete ◽  
Concrete Carbonation ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

Based on the coupling testing program of freeze-thaw and carbonation, the laboratory simulation test is carried out. The laws of carbonation depth of the fly ash concrete suffered the freeze-thaw cycle in different test modes and the influence of fly ash dosage on concrete carbonation depth after the freeze-thaw cycle are studied. Defining the influence coefficient of the freeze-thaw cycles on carbonation depth of concrete, the mechanism of coupling of freeze-thaw and carbonation is analyzed,and the role of freeze-thaw and carbonation in the coupling process are obtained.

The Role of Pressure Solution in Diagenesis of Carbonate Deposits: Theory and Laboratory Simulation

2018 ◽  
Vol 80 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Z. N. Skvortsova ◽  
V. Yu. Traskin ◽  
E. V. Porodenko ◽  
Ya. I. Simonov
Keyword(s):  
Laboratory Simulation ◽  
Pressure Solution ◽  
Carbonate Deposits

Whither shore platforms?

2010 ◽  
Vol 35 (2) ◽  
pp. 183-209 ◽  
Author(s):  
Rajarshi Dasgupta
Keyword(s):  
Collaborative Work ◽  
Laboratory Simulation ◽  
Future Research ◽  
Limited Attention ◽  
Data Sets ◽  
Quantitative Analyses ◽  
Geological Control ◽  
Precise Role ◽  
Shore Platforms

This paper reviews the research on shore platforms since 1980. Although some quantitative work on platforms was conducted in the late 1970s, it was principally in the 1980s that there was a change in the research paradigm, from qualitative observations to quantitative analyses. Researchers are now closer than ever before on agreeing that no single process can produce shore platforms in itself. The last decade has seen remarkable proliferation of research interests in shore platforms. Consequently, there are much-improved data sets on the processes acting on them. Even so, it has not yet been possible to establish definitively the precise role of each individual process in shore platform evolution. Laboratory simulation of platform morphodynamics has received much less attention compared to field-based studies. There are also some other aspects, such as threshold determination, geological control, inheritance, application of geo-informatics and focus on low-energy and tropical coasts, that have received limited attention. These areas are avenues for future research. To enable a better understanding of platform dynamics in a particular area, fieldwork, laboratory simulation and numerical modelling should be carried out simultaneously. Shore platforms are a global feature, and their study should be undertaken in all parts of the world through increased collaborative work among researchers.

Structure and composition of a post-fire ascomycete community: role of abiotic and biotic factors

1980 ◽  
Vol 58 (17) ◽  
pp. 1915-1922 ◽  
Author(s):  
J. C. Zak ◽  
D. T. Wicklow
Keyword(s):  
Species Diversity ◽  
Steam Treatment ◽  
Laboratory Simulation ◽  
Biotic Factors ◽  
Untreated Soil ◽  
Number Of Species ◽  
Soil Temperatures ◽  
Prairie Soil ◽  
Abiotic And Biotic Factors

The role of certain abiotic and biotic factors in determining the structure of a post-fire ascomycete community was studied by the laboratory simulation of soil conditions occurring during and following a prairie fire. Aerated steam treatment of prairie soil (35, 40, 55, 70, or 85 °C for 60 s) was used to simulate the elevated soil temperatures generated during a grassland fire. Further manipulations included: (1) addition of ashed remains of prairie grasses to steamed soil surfaces, (2) the incubation of steam-treated soil samples layered over untreated prairie soil, and (3) addition of ash to steamed soil underlain with a layer of untreated soil to create a simulated burn.Across all treatments, species diversity and total number of species were significantly higher in soils steamed at 35, 55, or 70 °C than soils steamed at 40 or 85 °C. The greatest number of species per sample for steaming alone occurred in samples treated at 55 °C. The addition of ash to steamed samples or layering with untreated prairie soil significantly reduced species diversity and total number of species as compared with steamed soil alone. When ash and a subsurface layer of untreated soil were applied together, species diversity, total number of species, and mean number of species for samples steamed at 55 or 70 °C, were significantly greater than when either treatment was added separately. It was found that a simulated burn at 55 or 70 °C promoted the development of a community which most closely resembled a naturally occurring post-fire ascomycete community. This suggested that the structure of the post-fire ascomycete community was in part determined by (1) species responses to elevated soil temperatures, (2) ash deposition, and (3) biotic factors associated with the subsurface soil layers.

scholarly journals 1729. Effect of Glove Disinfection on Bacterial Contamination of Healthcare Worker Hands

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S56-S56 ◽  
Author(s):  
Gwen Robinson ◽  
Zegbeh Z Kpadeh ◽  
Haleema Alserehi ◽  
Daniel Morgan ◽  
Anthony D Harris ◽  
...  
Keyword(s):  
Healthcare Worker ◽  
Bacterial Contamination ◽  
Potential Role ◽  
Bacterial Load ◽  
Laboratory Simulation ◽  
Log Reduction ◽  
Qualitative Detection ◽  
Bacterial Transmission ◽  
Research Grant

Abstract Background Disinfection of gloves and gowns was recommended to decrease healthcare worker (HCW) self-contamination during doffing of gloves and gowns in the Ebola epidemic. To understand the potential role of this practice in preventing bacterial transmission, we examined the effect of disinfectants on bacterial contamination of HCW hands following glove removal. Methods A laboratory simulation study was conducted using methicillin-susceptible Staphylococcus aureus and antibiotic-sensitive Klebsiella pneumoniae among volunteer HCWs (n = 10 per organism). For each experiment, the volunteer donned 2 pairs of gloves with the “under glove” simulating HCW hands and “top glove” simulating actual glove use in the clinical setting. The top-glove was inoculated with 108 CFU bacteria for each step. Top gloves were sampled directly after inoculation (Arm A), and after disinfection with alcohol gel, bleach wipes, and quaternary ammonium (quat) wipes, in separate steps (Arm B). Under gloves were sampled after top glove removal without disinfection (Arm C), and top glove removal post disinfection (Arm D). Quantitative bacterial load reduction was compared for glove use (Arm C − Arm A), and for disinfectant use in addition to glove use (Arm D − Arm C). Qualitative detection of any bacterial load (present/absent) on under glove in the setting of disinfection prior to top glove removal was also assessed. Results Of 108 CFU inoculated, the median recovery was 1.2 × 104 CFU (both bacteria combined). After glove removal (no disinfection), the median recovery from the under glove was 2.7 × 102 CFU, for a reduction of 98% (1.6 log) in bacterial load. After top glove disinfection and removal, the median bacterial recovery from the under glove was 1.4 × 102, 0, and 0 CFU for alcohol, quat, and bleach (47% or 0.3 log reduction for alcohol; 99% or 2 log reduction for quat and bleach) (Figure 1). Regardless of quantity, bacteria were recovered from under gloves even after top glove disinfection in 70%, 40%, and 35% cases for alcohol, quat, and bleach, respectively (Figure 2). Conclusion Glove disinfection prior to glove removal is effective at reducing bacterial contamination of HCW hands. However, despite disinfection, some level of hand contamination occurs frequently. Disclosures J. K. Johnson, Q-Linea: Investigator, Research grant. Applied Biocode: Investigator, Research grant

Dispositional Hardiness and Women's Well-Being Relating to Gender Discrimination: the Role of Minimization

2003 ◽  
Vol 27 (3) ◽  
pp. 197-208 ◽  
Author(s):  
Mindi D. Foster ◽  
Kenneth L. Dion
Keyword(s):  
Mental Health ◽  
Negative Affect ◽  
Gender Discrimination ◽  
Well Being ◽  
Self Esteem ◽  
Laboratory Simulation ◽  
The Third ◽  
Hypothetical Scenario ◽  
Mental Health Benefits

Three studies examined whether personality-based hardiness would be associated with mental health benefits in contexts of gender discrimination. Hardy women encountering both a laboratory simulation and a hypothetical scenario of discrimination showed greater self-esteem and less negative affect than low hardy women. However, these benefits were mediated by the use of specific attributions, suggesting that well-being in hardy women may have been achieved through minimizing the pervasiveness of discrimination. The third study showed this mediation pattern occurred only for participants exposed to higher threat scenarios versus lower threat scenarios of discrimination. Thus, minimizing the pervasiveness of discrimination may have been a threat-reducing tool for high hardy women. Bandura's (1997) self-efficacy theory was used as a possible explanation for this finding.

Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽  
1966 ◽  
Vol 195 (12) ◽  
pp. 1005-1009 ◽  
Author(s):  
D. J. Fernbach
Keyword(s):  
Wilms Tumor
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