Experimental and Numerical Analysis of the Relationship Between Indoor and Outdoor Airborne Particles in an Operating Room

Air pollution is a well-known problem for human health, especially for children living in highly polluted urban areas. This study aimed to assess the relationship between airborne pollutants concentration and biomarkers of DNA damage in the buccal mucosa cells of pre-school children. DNA damage was investigated with comet test in saliva leukocytes taken from sputum of 3- to 6-year-old children living in Brescia, Northern Italy, collected during two consecutive winter seasons (2012–2013). The daily levels of PM10, PM2.5, NO2, CO, SO2, benzene and O3 in urban air were collected for the whole period. A questionnaire filled in by the children’s parents was used to evaluate indoor and outdoor exposure. DNA damage in saliva leukocytes was evaluated in 152 children and the means of tail intensity and visual score as DNA damage were 6.2 ± 4.3 and 182.1 ± 30.9, respectively. No demographic and indoor or outdoor exposure variable was associated with the two measures of DNA damage. No significant association between air pollution and DNA damage in children’s buccal leukocytes was found. In this study, the comet assay does not appear to be a valuable biomarker to detect DNA damage in children exposed to high levels of air pollutants, such as PM10, PM2.5 and NO2.

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The relationship between indoor and outdoor Snellen visual acuity in cataract patients

Journal of Cataract & Refractive Surgery ◽

10.1016/s0886-3350(88)80061-0 ◽

1988 ◽

Vol 14 (1) ◽

pp. 35-39 ◽

Cited By ~ 11

Author(s):

Albert C. Neumann ◽

George R. McCarty ◽

Thomas O. Steedle ◽

Donald R. Sanders ◽

Marsha G. Raanan

Keyword(s):

Visual Acuity ◽

Snellen Visual Acuity ◽

The Relationship ◽

Cataract Patients ◽

Indoor And Outdoor

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Wound Ventilation With Ultraclean Air for Prevention of Direct Airborne Contamination During Surgery

Infection Control and Hospital Epidemiology ◽

10.1086/502395 ◽

2004 ◽

Vol 25 (4) ◽

pp. 297-301 ◽

Cited By ~ 12

Author(s):

Mikael Persson ◽

Jan van der Linden

Keyword(s):

Operating Room ◽

Median Number ◽

Airborne Particles ◽

University Hospital ◽

Surgical Wound ◽

Wound Model ◽

Wound Contamination ◽

Room Ventilation ◽

Airborne Contamination ◽

Number Of Particles

AbstractBackground and Objective:Despite the novelties in operating room ventilation, airborne bacteria remain an important source of surgical wound contamination. An ultraclean airflow from the ceiling downward may convey airborne particles from the surgical team into the wound, thus increasing the risk of infection. Therefore, similar ventilation from the wound upward should be considered. We investigated the effect of wound ventilation on the concentration of airborne particles in a wound model during simulated surgery.Design:Randomized experimental study simulating surgery with a wound cavity model.Setting:An operating room of a university hospital ventilated with ultraclean air directed downward.Interventions:Particles 5 um and larger were counted with and without a 5-cm deep cavity and with and with-out the insufflation of ultraclean air.Results:With the surgeon standing upright, no airborne particles could be detected in the wound model. In contrast, during simulated operations, the median number of particles per 0.1 cu ft reached 18 (25th and 75th percentiles, 12 and 22.25) in the model with a cavity and 15.5 (25th and 75th percentiles, 14 and 21.5) without. With a cavity, wound ventilation markedly reduced the median number of particles to 1 (range, 0 to 1.25;P< .001).Conclusions:To protect a surgical wound against direct airborne contamination, air should be directed away from the wound rather than toward it. This study provides supportive evidence to earlier studies that operating room ventilation with ultraclean air is imperfect during surgical activity and that wound ventilation may be a simple complement. Further clinical trials are needed.

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The relationship between the retinal image quality and the refractive index of defects arising in IOL: numerical analysis

Applications of Digital Image Processing XL ◽

10.1117/12.2274337 ◽

2017 ◽

Author(s):

Malwina Geniusz

Keyword(s):

Refractive Index ◽

Numerical Analysis ◽

Image Quality ◽

Retinal Image ◽

The Relationship

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Numerical Analysis of Dynamic Compaction based on Large Deformation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.168-170.330 ◽

2010 ◽

Vol 168-170 ◽

pp. 330-333

Author(s):

Neng Gang Xie ◽

Yun Chen ◽

Ye Ye ◽

Lu Wang

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Numerical Analysis ◽

Large Deformation ◽

Governing Equation ◽

Dynamic Compaction ◽

Iterative Calculation ◽

Non Linear ◽

The Relationship ◽

Element Method

In the numerical analysis of foundation consolidation by using dynamic compaction, many kinds of non-linear conditions exist. This paper adopts large deformation on the relationship between strain and displacement. Non-linear governing equation of soil, based on finite element method, is established. Iterative calculation form is raised. Finally, non-linear numerical analysis is done to a calculation example.

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A Simulation Research for Railroad Freight Car-to-Car End Impact Based on Numerical Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.1020 ◽

2015 ◽

Vol 764-765 ◽

pp. 1020-1025 ◽

Cited By ~ 1

Author(s):

Meng Qi Ma ◽

Fang Ping Lei ◽

Yu Qiao Ren ◽

Bai Song Mu

Keyword(s):

Numerical Analysis ◽

Kinematic Model ◽

Kutta Method ◽

Simulation Research ◽

Runge Kutta Method ◽

Freight Car ◽

Runge Kutta ◽

Relationship Of ◽

The Relationship ◽

Railroad Freight

A method of establishing a kinematic model for simulated railroad freight car impact based on the Runge-Kutta method is introduced in this paper. The model is solved based on numerical analysis to obtain the relationship of variables, furthermore providing a basis for determining the loading support and loading securement method.

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Taxonomy of the Carex straminea complex (Cyperaceae)

Canadian Journal of Botany ◽

10.1139/b97-929 ◽

1997 ◽

Vol 75 (12) ◽

pp. 2177-2195 ◽

Cited By ~ 5

Author(s):

P. E. Rothrock ◽

A. A. Reznicek ◽

L. R. Ganion

Keyword(s):

Numerical Analysis ◽

North America ◽

Key Words ◽

Endemic Species ◽

Atlantic Coast ◽

Interspecific Variation ◽

Eastern North America ◽

Upper Midwest ◽

The Relationship ◽

Sem Investigation

The Carex straminea complex (section Ovales) consists of five species limited to hydric communities of eastern North America. Based upon gross morphology and perigynium structure, these species are closely aligned with the Carex albolutescens complex but not the western species Carex feta. An SEM investigation of the micromorphology of achene and style epidermis from 15 species of Carex section Ovales demonstrated much interspecific variation. As a result, these data could not confirm the relationship between the C. straminea complex and the C. albolutescens complex but did support the delimitation of section Ovales. Numerical analysis showed that characters of the inflorescence and perigynium are satisfactory for separating C. straminea from Carex hormathodes, a species limited to the Atlantic coast. Likewise, characters of inflorescence, pistillate scale, and perigynium could clearly separate the geographically widespread Carex alata from the Florida endemic species Carex vexans. A fifth and relatively distinctive species, Carex suberecta, was found to have a narrow ecological preference for fens and a distribution limited to the upper Midwest, with outlying populations in western Virginia. Putative natural hybrids are documented between Carex scoparia and Carex longii and some species in the C. straminea complex. Key words: Carex, Cyperaceae, section Ovales, taxonomy, SEM, biogeography, hybrid.

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