Three dimensional analysis of the exhalation flow in the proximity of the mouth.

The human exhalation flow is characterized in this work from the three-dimensional velocimetry results obtained by using the stereo particle image velocimetry (SPIV) measurement technique on the flow emitted from a realistic airway model. For this purpose, the transient exhalation flow through the mouth of a person performing two different breaths corresponding to two metabolic rates, standing relaxed (SR) and walking active (WA), is emulated and studied. To reproduce the flow realistically, a detailed three-dimensional model obtained from computed tomography measurements on real subjects is used.

Exhaled contaminant concentration data in a hospital room influenced by external heat gains.

A hospital room is simulated using two breathing thermal manikins representing a health worker (HW) and a patient in repose (PR). The PR exhales R134a simulating small exhaled particles (<5 μm) and the contaminant concentration around and in the inhalation of HW is measured during a period of 2 hours per experiment. The room is climatized to maintain constant air temperature values of 25 °C using two wall mounted grilles and two exhausts.

Assessment of displacement ventilation systems in airborne infection risk in hospital rooms.

Efficient ventilation in hospital airborne isolation rooms is important vis-à-vis decreasing the risk of cross infection and reducing energy consumption. This paper analyses the suitability of using a displacement ventilation strategy in airborne infection isolation rooms, focusing on health care worker exposure to pathogens exhaled by infected patients. The analysis is mainly based on numerical simulation results obtained with the support of a 3-D transient numerical model validated using experimental data.

Experimental analysis of the air velocity and contaminant dispersion of human exhalation flows.

Human exhalation flow is a potential source of pathogens that can constitute a cross-infection risk to people in indoor environments. Thus, it is important to investigate the characteristics of this flow, its development, area of influence, and the diffusion of the exhaled contaminants. This paper uses phase-averaged particle image velocimetry together with a tracer gas (CO ) to study two different exhalation flows over time: the exhalation of an average male (test M) and an average female (test F), using a life-sized thermal manikin in a supine position.

Nasomaxillary reconstruction in Binder syndrome: bone versus cartilage grafts. A long-term intercenter comparison between Sweden and Mexico.

Maxillonasal dysplasia is characterized by a concave facial profile and a flat nose. The etiology of Binder syndrome is skeletal hypoplasia around the piriform aperture and excavations-fossae prenasales, bilaterally in the nasal floor-which are pathognomonic. There is no real shortage of the soft tissues.