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Noise in the ICU patient room - Staff knowledge and clinical improvements

Introduction: The acoustic environment in the intensive care unit patient room, with high sound levels and unpredictable sounds, is known to be poor and stressful. Therefore, the present study had two aims: to investigate staff knowledge concerning noise in the intensive care unit and: to identify staff suggestions for improving the sound environment in the intensive care unit patient room. Method

The Being Taken Seriously Questionnaire—Development and Psychometric Evaluation of a PREM Measure for Person-Centeredness in a High-Tech Hospital Environment

There is a need for patient-reported experience measures (PREMs) in high-tech hospital environments based on the philosophy of person-centeredness. The aim of this study was to describe the development and initial psychometric evaluation of a measure of person-centeredness by means of being taking seriously. In this cross-sectional survey, the study sample (n = 79) completed two measures, the Bein

The patient experience of intensive care : A meta-synthesis of nordic studies

Background: Sedation practices in the intensive care unit have evolved from deep sedation and paralysis toward lighter sedation and better pain management. The new paradigm of sedation has enabled early mobilization and optimized mechanical ventilator weaning. Intensive care units in the Nordic countries have been particularly close to goals of lighter or no sedation and a more humane approach to

Lighting, sleep and circadian rhythm : An intervention study in the intensive care unit

Patients in an intensive care unit (ICU) may risk disruption of their circadian rhythm. In an intervention research project a cycled lighting system was set up in an ICU room to support patients' circadian rhythm. Part I aimed to compare experiences of the lighting environment in two rooms with different lighting environments by lighting experiences questionnaire. The results indicated differences

Insects and other invertebrate remains from the coffin of a 17th century bishop in Lund Minster, S Sweden

An extraordinarily diverse and well-preserved material, including the remains of 47 insect taxa and 12 taxa of other invertebrates, extracted from the 17th century burial of Bishop Peder Winstrup in Lund Minster, is presented and discussed in terms of the treatment of the body, activities connected with the burial and faunal significance. The invertebrate assemblages include species from gardens,

A Comparison of Airborne Particles Generated from Disk Brake Contacts : Induction Versus Frictional Heating

Abstract: Volatile emissions of vehicle brakes relate to the high temperature of the brake friction pair. However, as a passive parameter of braking applications, temperature is usually studied together with other parameters such as sliding speed and load. Heating tests that increase the friction pair temperature with an induction heater instead of friction are proposed in this study to imitate th

Friction, wear and airborne particle emission from Cu-free brake materials

Cu is required to be abated in brake pads due to its toxicity. There are on the market several Cu-free brake pads. These Cu-free brake pads are only evaluated regarding their friction and wear performance, whereas, their airborne particle emissions are not considered. A pin-on-disc tribometer is used to evaluate the friction, wear and airborne particle emission from two Cu-free commercial brake pa

A proposed driving cycle for brake emissions investigation for test stand

Particulate matter emission factors from vehicle brakes are difficult to assess directly from the field. Moreover, there is a lack of a standardized cycle and test stand for evaluating brake emissions. For these reasons, a test cycle was developed from real driving data collected from a car. This new test cycle was implemented on an inertia disc brake dynamometer appositely designed for brake part

A pin-on-disc tribometer study of friction at low contact pressures and sliding speeds for a disc brake material combination

Disc brake creep groan is a stick-slip phenomenon which results in a low frequency noise in road vehicles that could occur at low vehicle speeds and brake torques. Simulation approaches are used predict the stick-slip phenomena for disc brakes. These approaches depend on the friction model used. Tribometers can be used to map how the local coefficient of friction (CoF) depends on the contact press

A multi-scale simulation approach to investigate local contact temperatures for commercial Cu-full and Cu-free brake pads

Copper from vehicles disc brakes is one main contributor of the total copper found in the environment. Therefore, the U.S. Environmental Protection Agency (EPA) and the automotive industries started the Copper-Free Brake Initiative. The pad friction material is essentially composed of a binder, fillers, reinforcing fibres and frictional additives. Copper and brass fibres are the most commonly used

A test stand study on the volatile emissions of a passenger car brake assembly

Brake-related airborne particulate matter contributes to urban emissions in the transport sector. Recent research demonstrated a clear dependence of the number of ultra-fine particles on the disc brake temperature. Above the so-called transition temperature, the number of ultra-fine particles increases dramatically (several magnitudes). As for exhaust emissions, part of the emissions released duri

An FEA approach to simulate disc brake wear and airborne particle emissions

Emissions from disc brake wear adversely affect the air quality in cities. Finite Element Analysis (FEA)approaches focussing on the macroscopic wear of pads and rotors can be found in the literature, but none of these take the wear and emission dependence of the local contact pressure and sliding speed into account. The aim of the present study is to further develop an FEA approach for simulation

Simulation of contact area and pressure dependence of initial surface roughness for cermet-coated discs used in disc brakes

Friction, wear, and emission performance strongly depend on the contact pressure and area at the interface of the pad and disc. The contact situation at the pad-to-disc interface can be explained by the formation and destruction of mesoscopic sized contact plateaus on the pad surface. Experimental studies report that the initial surface roughness of cermet-coated discs strongly affects friction, w

A pin-on-disc study on the tribology of cast iron, sinter and composite railway brake blocks at low temperatures

Most freight wagons in the EU use cast iron brake blocks. Cast iron brake blocks have a stable braking capability in different environmental conditions, but wear down the wheel tread quickly. Therefore, there is a need to understand the tribology of other brake block materials. A pin-on-disc tribometer placed in a temperature-controlled chamber is used to investigate the tribology of cast iron, si

Towards a two-part train traffic emissions factor model for airborne wear particles

In 2017 a new railway tunnel containing two stations opened in Stockholm, Sweden. A series of field measurements were carried out on the platforms in this tunnel before and after it was opened for normal traffic. These measurements were used to investigate the contribution of airborne particle emissions from wear processes to total train emissions. This field data was used to develop a two-part tr

A friction, wear and emission tribometer study of non-asbestos organic pins sliding against alsic mmc discs

The friction, wear and particle emission from an AlSiC MMC brake disc/non-asbestos organic brake pad system is studied using a pin-on-disc tribometer. The results show that this unconventional AlSiC MMC brake disc system presents friction performance as good as a conventional cast iron brake disc system. During braking, brake pad materials are transferred to the brake disc surface to form a protec

Scaling effects of measuring disc brake airborne particulate matter emissions – A comparison of a pin-on-disc tribometer and an inertia dynamometer bench under dragging conditions

An important contributor to non-exhaust emissions in urban areas is airborne particulate matter originating from brake systems. A well-established way to test such systems in industry is to use inertia dynamometer benches; although they are quite expensive to run. Pin-on-disc tribometers, on the other hand, are relatively cheap to run, but simplify the real system. The literature indicates promisi

On the influence of car brake system parameters on particulate matter emissions

The influence of car brake system parameters on particulate matter emissions was investigated using a pin-on-disc tribometer. Samples from a low-steel friction material and a cast iron disc were tested for different sliding velocities, nominal contact pressures and frictional powers. Disc temperatures were also measured. Their impact on total concentration, size distribution, particle coefficient

Contact pressure and sliding velocity maps of the friction, wear and emission from a low-metallic/cast-iron disc brake contact pair

Particulate matter with an aerodynamic diameter less than 10 µm (PM10) from car disc brakes contribute up to 50% of the total non-exhaust emissions from road transport in the EU. These emissions come from the wear of the pad and rotor contact surfaces. Yet few studies have reported contact pressures and offered sliding speed maps of the friction, wear, and particle emission performance of disc bra

A concept for reducing PM10 emissions for car brakes by 50%

With regard to airborne particles with an aerodynamic diameter of less than 10 µm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had t