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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

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

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

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

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

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

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

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

Within the policy debate, there is a fear that large incumbent firms buy small firms' inventions to ensure that they are not used in the market. We show that such "acquisitions for sleep" can occur if and only if the quality of a process invention is small; otherwise, the entry profit will be higher than the entry-deterring value. We then show that the incentive for acquiring for the purpose of pu

The rooms in Intensive Care Units are considered as high-tech environments and believed to affect recovery process and wellbeing of patients. Moreover, the design and interiors affect the interplay between the patient and the next of kin. Objective: The aim of this study was to describe and interpret the meanings of the intensive care patient room as experienced by next of kin. Design: Next of kin

The aim of this study was to illuminate the meanings of being critically ill in a sound-intensive ICU patient room, as disclosed through patients' narratives. Patient rooms in ICUs are filled with loud activity and studies have revealed sound levels comparable to those of a busy road above the patient's head. There is a risk that the sound or noise is disturbing and at worst a major problem for th

Aim. This study describes the meanings of generalist registered nurses' experiences of caring for palliative care patients on general wards in hospitals. Background. Earlier research shows that work with patients in palliative care is demanding. More research concerning palliative care is undertaken in oncological care, in hospice and in home-care settings than in general wards. It is therefore im

The importance of the gut microbiota in human health has led to an increased interest to study probiotic bacteria. Fermented food is a source of already established probiotics, but it also offers an opportunity to discover new taxa. Four strains of Weissella sp. isolated from Indian fermented food have been genome sequenced and classified into the species W. cibaria based on whole-genome phylogeny

Importance: Better understanding is needed of the degree to which individuals tolerate Alzheimer disease (AD)-like pathological tau with respect to brain structure (brain resilience) and cognition (cognitive resilience). Objective: To examine the demographic (age, sex, and educational level), genetic (APOE-ϵ4 status), and neuroimaging (white matter hyperintensities and cortical thickness) factors

Aim: To study global patterns and temporal changes in the seasonal dynamics (quantity and seasonal distribution) of terrestrial gross carbon uptake in response to global environmental change. Location: Global. Time period: 2000–2016. Major taxa studied: Terrestrial ecosystems. Methods: Following a phenology-based definition of photosynthetic seasonality, we decompose gross primary production (GPP)

Study Design: A nonblinded randomized controlled trial. Introduction: Occupation-based interventions are superior to physical exercise–based interventions in patients with activity limitations. However, only a few studies have examined the effect in patients with hand-related disorders. Patients recover heterogeneously, which could be due to personal factors, such as sense of coherence (SOC). Purp

This study had two aims: first to describe, using both descriptive statistics and quantitative content analysis, the noise environment in an ICU patient room over one day, a patient's physical status during the same day and early signs of ICU delirium; second, to describe, using qualitative content analysis, patients' recall of the noise environment in the ICU patient room. The final study group c

Background and objectives: Fetal RHD genotyping of cell-free maternal plasma DNA from RhD negative pregnant women can be used to guide targeted antenatal and postnatal anti-D prophylaxis for the prevention of RhD immunization. To assure the quality of clinical testing, we conducted an external quality assessment workshop with the participation of 31 laboratories. Materials and methods: Aliquots of

Prospective studies using video-recordings of patients during mechanical ventilator treatment (MVT) while conscious have not previously been published. The aim was to describe patients' statements, communication and facial expressions during a video-recorded interview while undergoing MVT. Content analysis and hermeneutics inspired by the philosophy of Gadamer were used. The patients experienced a

Children using mechanical ventilation for survival represent a small, but growing, vulnerable population in society. The aim of this study was to describe the existing qualitative research that examined family members' experiences when a child is dependent on ventilator at home. A metasynthesis is an interpretative integration of qualitative research findings based on a systematic literature searc