Testing and evaluating real driving emissions with PEMS

Testing of real driving emissions (RDE) with portable emission measuring system (PEMS) in an appropriate road circuit became an obligatory element of new type approval of passenger cars since September 2017. In several projects the Laboratory for Exhaust Emissions Control (AFHB) of the Berne University of Applied Sciences (BFH) performed comparisons on passenger cars with different PEMS’s on chassis dynamometer and on road, considering the quality and the correlations of results. Particle number measuring systems (PN PEMS) were also included in the tests. The present paper informs about influences of E85 on RDE on two flex-fuel-vehicles, discusses some aspects of different ways of evaluation with different programs, shows comparison of different types of PN PEMS and represents the effects of simulation of slope on the chassis dynamometer

Chemical priming of immunity without costs to plant growth

- β-aminobutyric acid (BABA) induces broad-spectrum disease resistance, but also represses plant growth, which has limited its exploitation in crop protection. BABA perception relies on binding to the aspartyl-tRNA synthetase (AspRS) IBI1, which primes the enzyme for secondary defense activity. This study aimed to identify structural BABA analogues that induce resistance without stunting plant growth. - Using site-directed mutagenesis, we demonstrate that the (L)-aspartic acid-binding domain of IBI1 is critical for BABA perception. Based on interaction models of this domain, we screened a small library of structural BABA analogues for growth repression and induced resistance against biotrophic Hyaloperonospora arabidopsidis (Hpa). - A range of resistance-inducing compounds were identified, of which (R)-β-homoserine (RBH) was the most effective. Surprisingly, RBH acted through different pathways than BABA. RBH-induced resistance (RBH-IR) against Hpa functioned independently salicylic acid, partially relied on camalexin, and was associated with augmented cell wall defense. RBH-IR against necrotrophic Plectosphaerella cucumerina acted via priming of ethylene and jasmonic acid defenses. RBH-IR was also effective in tomato against Botrytis cinerea. Metabolic profiling revealed that RBH, unlike BABA, does not majorly affect plant metabolism. - RBH primes distinct defense pathways against biotrophic and necrotrophic pathogens without stunting plant growth, signifying strong potential for exploitation in crop protection

Effects of metal-on-metal wear on the host immune system and infection in hip arthroplasty

Methods We reviewed the available literature on the influence of degradation products of MOM bearings in total hip arthroplasties on infection risk. Results Wear products were found to influence the risk of infection by hampering the immune system, by inhibiting or accelerating bacterial growth, and by a possible antibiotic resistance and heavy metal co-selection mechanism. Interpretation Whether or not the combined effects of MOM wear products make MOM bearings less or more prone to infection requires investigation in the near future

Pathogenic Mechanisms and Host Interactions in Staphylococcus epidermidis Device-Related Infection

Staphylococcus epidermidis is a permanent member of the normal human microbiota, commonly found on skin and mucous membranes. By adhering to tissue surface moieties of the host via specific adhesins, S. epidermidis is capable of establishing a lifelong commensal relationship with humans that begins early in life. In its role as a commensal organism, S. epidermidis is thought to provide benefits to human host, including out-competing more virulent pathogens. However, largely due to its capacity to form biofilm on implanted foreign bodies, S. epidermidis has emerged as an important opportunistic pathogen in patients receiving medical devices. S. epidermidis causes approximately 20% of all orthopedic device-related infections (ODRIs), increasing up to 50%in late-developing infections. Despite this prevalence, it remains underrepresented in the scientific literature, in particular lagging behind the study of the S. aureus. This review aims to provide an overview of the interactions of S. epidermidis with the human host, both as a commensal and as a pathogen. The mechanisms retained by S. epidermidis that enable colonization of human skin as well as invasive infection, will be described, with a particular focus upon biofilm formation. The host immune responses to these infections are also described, including how S. epidermidis seems to trigger low levels of pro-inflammatory cytokines and high levels of interleukin-10, which may contribute to the sub-acute and persistent nature often associated with these infections. The adaptive immune response to S. epidermidis remains poorly described, and represents an area which may provide significant new discoveries in the coming years

A call for action to the biomaterial community to tackle antimicrobial resistance

The global surge of antimicrobial resistance (AMR) is a major concern for public health and proving to be a key challenge in modern disease treatment, requiring action plans at all levels. Microorganisms regularly and rapidly acquire resistance to antibiotic treatments and new drugs are continuously required. However, the inherent cost and risk to develop such molecules has resulted in a drying of the pipeline with very few compounds currently in development. Over the last two decades, efforts have been made to tackle the main sources of AMR. Nevertheless, these require the involvement of large governmental bodies, further increasing the complexity of the problem. As a group with a long innovation history, the biomaterials community is perfectly situated to push forward novel antimicrobial technologies to combat AMR. Although this involvement has been felt, it is necessary to ensure that the field offers a united front with special focus in areas that will facilitate the development and implementation of such systems. This paper reviews state of the art biomaterials strategies striving to limit AMR. Promising broad-spectrum antimicrobials and device modifications are showcased through two case studies for different applications, namely topical and implantables, demonstrating the potential for a highly efficacious physical and chemical approach. Finally, a critical review on barriers and limitations of these methods has been developed to provide a list of short and long-term focus areas in order to ensure the full potential of the biomaterials community is directed to helping tackle the AMR pandemic

Real Driving Emissions in Extended Driving Conditions

The real driving emission (RDE) testing for certification of vehicles is performed in conditions that are well defined in legislation. For emissions inventories and for research, the influences of some extended driving conditions on emissions are an interesting issue. In the present work, some examples of RDE results from two common passenger cars with gasoline and diesel propulsion are given. The varying driving conditions were “winter/summer”, “mild/aggressive”, and “higher altitude/slop”. The driving conditions: “winter”, “aggressive”, and “higher slope/altitude” gen-erally require more energy, cause higher fuel consumption, and therefore, higher CO2-emissions. The condition of “winter driving”, especially in the urban type of operation, may cause some longer phases with not enough warmed-up exhaust aftertreatment and consequently some in-creased gaseous emissions. The DPF eliminates the nanoparticles (PN) independently on the driving conditions. Nevertheless, the DPF regeneration has an influence on the CO2-normality of the trip. The CO2-normality primary tolerance range can also be exceeded with aggressive driving. The elaborated results confirm the usefulness of the existing legal limits for the driving conditions of RDE homologation tests

Liquefied Methane as a Fuel in Swiss Heavy-duty Trucks

The decarbonization of vehicles in the heavy-duty sector is an important contribution to achieving the climate protection targets agreed in Paris. In an interdisciplinary project led by the Bern University of Applied Sciences for Engineering and Informion Technology and the Ostschweizer Fachhochschule, the substitution of conventional diesel fuel with liquefied methane for heavy-duty commercial vehicles is being studied holistically