Effects of steam curing regimes on the capillary water absorption of concrete: Prediction using multivariable regression models

Understanding periods of the year associated with higher risk for falling and less physical activity may guide fall prevention and activity promotion for older adults. We examined the relationship between weather and seasons on falls and physical activity in a three-year cohort of older adults with glaucoma. Participants recorded falls information via monthly calendars and participated in four one-week accelerometer trials (baseline and per study year). Across 240 participants, there were 406 falls recorded over 7569 person-months, of which 163 were injurious (40%). In separate multivariable regression models incorporating generalized estimating equations, temperature, precipitation, and seasons were not significantly associated with the odds of falling, average daily steps, or average daily active minutes. However, every 10 °C increase in average daily temperature was associated with 24% higher odds of a fall being injurious, as opposed to non-injurious (p = 0.04). The odds of an injurious fall occurring outdoors, as opposed to indoors, were greater with higher average temperatures (OR per 10 °C = 1.46, p = 0.03) and with the summer season (OR = 2.69 vs. winter, p = 0.03). Falls and physical activity should be understood as year-round issues for older adults, although the likelihood of injury and the location of fall-related injuries may change with warmer season and temperatures.

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Modeling Capillary Water Absorption in Concrete with Discrete Crack Network

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0002122 ◽

2018 ◽

Vol 30 (1) ◽

pp. 04017263 ◽

Cited By ~ 11

Author(s):

Xinxin Li ◽

Shenghong Chen ◽

Qing Xu ◽

Yi Xu

Keyword(s):

Water Absorption ◽

Capillary Water ◽

Crack Network ◽

Capillary Water Absorption ◽

Discrete Crack

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Abstract 3572: Clinical Outcomes of the “Stroke100 Club”

Stroke ◽

10.1161/str.43.suppl_1.a3572 ◽

2012 ◽

Vol 43 (suppl_1) ◽

Author(s):

Amy K Guzik ◽

Rema Raman ◽

Kain Ernstrom ◽

Dawn M Meyer ◽

Ajeet Sodhi ◽

...

Keyword(s):

Regression Models ◽

Young Patients ◽

Older Age ◽

Advanced Age ◽

Stroke Severity ◽

Old Patients ◽

Multivariable Regression ◽

Independent Variable ◽

Poor Outcomes ◽

Multivariable Regression Models

Background: Patients with advanced age or high NIHSS have poorer tPA outcomes. When combined, old age (≥80yo) and elevated NIHSS (≥20) may have an even worse outcome. Patients who are also in this “Stroke100 Club” (any combination of age and NIHSS ≥100) by other means, have not been fully assessed. We evaluated discharge destination, 90-day mRS, sICH and death in treated and untreated Stroke100 Club patients. We further compared patients with age ≥ 80 and NIHSS ≥ 20 (“80/20s”), those who reached 100 without both characteristics (“non80/20s”) and ‘controls’. Methods: The UCSD SPOTRIAS prospectively collected database was analyzed for AIS patients (with and without tPA). Multivariable regression models including the Stroke100 group as an independent variable was used. Outcomes were adjusted for baseline mRS. For comparing categorical outcomes between controls, “80/20s” and “non80/20s” subgroups, a Fisher’s exact was used. Results: The IV tPA subset included 257 patients (mean age 71, 52% male, 85% white, mean NIHSS 12). 53 were in the “Stroke100 Club” (28 80/20, 25 non80/20), with more women (68% p= 0.002), higher NIHSS (22.5 p<0.0001), older age (mean age 86.4 p<0.0001), higher pre stroke mRS (34.6% mRS 3-6 vs 7.84%, p<0.0001), more HTN (p=0.045) and more afib (p= 0.008). There were 284 non tPA patients (mean age 69.52, 54% male, 85% white, mean NIHSS 5.92). 21 were in the “Stroke100 Club” (14 80/20, 7 non80/20), with higher NIHSS (23 p<0.0001), older age (mean 86.2 p<0.0001), higher pre stroke mRS (45.5% 3-6 vs 9.5%, p= 0.0001), and more afib (p= 0.0002). Stroke100 Club 90day mRS(3-6) outcomes were worse in both tPA treated patients (OR=6.77, p= 0.0001) and nontreated patients (OR 31.57, p= 0.001). sICH rates (in tPA subjects) were not different (3.8% vs 3.4%, p> 0.99). Conclusions: There is a question of treatment outcome in patients with various permutations of stroke severity and advanced age. Our data corroborates the concern of poor outcomes for Stroke100 Club patients, but notes no increased sICH with tPA. Though outcome may be poor, withholding tPA should be discouraged as worse outcomes were not due to sICH. Young patients with severe strokes or old patients with mild strokes may have outcomes similar to the standard “80/20” Stroke100 patients, however further adjusted analysis is ongoing. In addition, further analyses are being done to compare tPA to non tPA patients.

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Effects of Imposed Damage on the Capillary Water Absorption of Recycled Aggregate Concrete

Advances in Materials Science and Engineering ◽

10.1155/2018/2890931 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Qi Gao ◽

Zhiming Ma ◽

Jianzhuang Xiao ◽

Fuan Li

Keyword(s):

Absorption Coefficient ◽

Water Absorption ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Capillary Absorption ◽

Capillary Water ◽

Aggregate Concrete ◽

Capillary Water Absorption ◽

Freeze Thaw ◽

Loading Level

Capillary water absorption of concrete is closely related to its pore structure, permeability, and durability. This paper intensively investigates the effects of imposed damage, including freeze-thaw damage and loading damage, on the capillary water absorption of recycled aggregate concrete (RAC). Freeze-thaw cycle test, loading test, and the experiment of capillary water absorption were carried out, respectively. The results demonstrate that the addition of recycled coarse aggregate (RCA) results in the increase in the capillary absorption behavior of RAC without imposed damage, and there exists a linear correlation between the behaviors of capillary water absorption and chloride penetration of RAC. The imposed freeze-thaw damage or load damage of RAC boosts with the increase of RCA replacement percentages after suffering the same freeze-thaw cycles or loading level. The imposed freeze-thaw damage and load damage further lead to the increase in the capillary water absorption of RAC, and the capillary absorption coefficient of RAC increases linearly with the increased RCA replacement percentages, after suffering the same freeze-thaw cycles or loading level. Furthermore, capillary absorption coefficient increases linearly with the growth of imposed freeze-thaw damage or load damage degree, which can be used to estimate the capillary absorption behavior of RAC exposed to the extreme environment.

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Relationship Between Capillary Water Absorption Value, Capillary Water Absorption Speed, and Capillary Rise Height in Pyroclastic Rocks

Mining Metallurgy & Exploration ◽

10.1007/s42461-020-00354-y ◽

2020 ◽

Author(s):

İsmail İnce

Keyword(s):

Water Absorption ◽

Capillary Rise ◽

Capillary Water ◽

Pyroclastic Rocks ◽

Capillary Water Absorption ◽

Rise Height

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The Influence of 30 Years Outdoor Weathering on the Durability of Hydrophobic Agents Applied on Obernkirchener Sandstones

Buildings ◽

10.3390/buildings10010018 ◽

2020 ◽

Vol 10 (1) ◽

pp. 18 ◽

Cited By ~ 2

Author(s):

Jeanette Orlowsky ◽

Franziska Braun ◽

Melanie Groh

Keyword(s):

Water Absorption ◽

Water Uptake ◽

Capillary Water ◽

Capillary Water Absorption ◽

Absorption Determination ◽

Colour Changes ◽

Uptake Velocity ◽

Outdoor Weathering

The durability of eleven different water repellents applied on one sandstone type was studied after a long-term weathering at seven different locations in Germany. By measuring colour changes, it could be shown that the formation of black crusts, the deposition of particles and biogenic growth caused a gradual darkening as well as significant changes in total colour over time. Additionally, the water absorption behaviour was investigated with two different methods: applying a low pressure using the pipe method and capillary water absorption measurements from a wet underlay. Afterwards, the test results were analysed with four different evaluation methods: calculation of the protection degree from pipe method and capillary water absorption, determination of the velocity of water uptake during capillary water absorption and calculation of the damaged depth of the stone surface using single-sided NMR technique. The growing damaged depth leads to an increase of the water uptake velocity and to a decrease of the protection degree of the applied hydrophobing agents. Three protective agents based on isobutyltrimethoxysilane showed already after two years of outdoor weathering a clear loss of performance, which significantly increased after 30 years of exposure.

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Preadmission Corticosteroid Therapy and the Risk of Respiratory Failure in Adults Without HIV Presenting With Pneumocystis Pneumonia

Journal of Intensive Care Medicine ◽

10.1177/0885066619834242 ◽

2019 ◽

Vol 35 (12) ◽

pp. 1465-1470 ◽

Cited By ~ 2

Author(s):

Patrick M. Wieruszewski ◽

Erin F. Barreto ◽

Jason N. Barreto ◽

Hemang Yadav ◽

Pritish K. Tosh ◽

...

Keyword(s):

Respiratory Failure ◽

Corticosteroid Therapy ◽

Regression Models ◽

Pneumocystis Pneumonia ◽

Severe Respiratory Failure ◽

Corticosteroid Administration ◽

Multivariable Regression ◽

Multivariable Regression Models ◽

Reduced Risk ◽

Hiv Negative

Background: Corticosteroid therapy is a well-recognized risk factor for Pneumocystis pneumonia (PCP); however, it has also been proposed as an adjunct to decrease inflammation and respiratory failure. Objective: To determine the association between preadmission corticosteroid use and risk of moderate-to-severe respiratory failure at the time of PCP presentation. Methods: This retrospective cohort study evaluated HIV-negative immunosuppressed adults diagnosed with PCP at Mayo Clinic from 2006 to 2016. Multivariable regression models were used to evaluate the association between preadmission corticosteroid exposure and moderate-to-severe respiratory failure at presentation. Results: Of the 323 patients included, 174 (54%) used preadmission corticosteroids with a median daily dosage of 20 (interquartile range: 10-40) mg of prednisone or equivalent. After adjustment for baseline demographics, preadmission corticosteroid therapy did not decrease respiratory failure at the time of PCP presentation (odds ratio: 1.23, 95% confidence interval: 0.73-2.09, P = .38). Additionally, after adjusting for inpatient corticosteroid administration, preadmission corticosteroid use did not impact the need for intensive care unit admission ( P = .98), mechanical ventilation ( P = .92), or 30-day mortality ( P = .11). Conclusions: Corticosteroid exposure before PCP presentation in immunosuppressed HIV-negative adults was not associated with a reduced risk of moderate-to-severe respiratory failure.

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Analysis of the Effect of Nano-SiO2 and Waterproofing Agent on the Water Transportation Process in Mortar Using NMR

Applied Sciences ◽

10.3390/app10217867 ◽

2020 ◽

Vol 10 (21) ◽

pp. 7867

Author(s):

Tao Meng ◽

Huadong Wei ◽

Kanjun Ying ◽

Menghua Wang

Keyword(s):

Water Absorption ◽

Moisture Diffusion ◽

Test Results ◽

Capillary Water ◽

Process Data ◽

Capillary Water Absorption ◽

Nano Sio2 ◽

Water Transportation ◽

Cement Based Materials ◽

Transportation Process

Moisture diffusion in cement-based materials significantly impacts its durability. In this study, we analyzed the effect of adding a waterproofing agent and nano-SiO2 (NS) on the water transportation process in mortar using capillary water absorption tests and nuclear magnetic resonance (NMR) technology. The results indicate that the combined action of the waterproofing agent and nano-SiO2 drastically reduce the capillary water absorption coefficient and have a more significant impact than only adding the waterproofing agent. The moisture diffusion in different sections of the mortar during the water absorption process is obtained from the NMR test results and two function models. Comparative studies indicate that the NMR test results have good correlation with the capillary water absorption test results and provide accurate process data. The NMR analysis results offer a new analytical method to characterize the porosity of cement-based materials by continuously monitoring small-pitch sections.

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