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To meet climate targets, a global shift away from fossil fuels is essential. For sectors where electrification is impractical, it is crucial to find sustainable energy carriers. Renewable methanol is widely considered a promising fuel for powering heavy-duty applications like shipping, freight transport, agriculture, and industrial machines due to its various sustainable production methods. While current technological efforts focus mainly on dual-fuel engines in shipping, future progress hinges on single-fuel solutions using renewable methanol to achieve net-zero goals in the heavy-duty sector. This review examines the research status of technologies enabling methanol as the sole fuel for heavy-duty applications. Three main categories emerged from the literature: spark-ignition, compression-ignition, and pre-chamber systems. Each concept's operational principles and characteristics regarding efficiency, stability, and emissions were analyzed. Spark-ignition concepts are a proven and cost-effective solution with high maturity. However, they face limitations due to knock issues, restricting power output with larger bore sizes. Compression-ignition concepts inherently do not suffer from end-gas autoignition, but encounter challenges related to ignitability due to the low cetane number of methanol. Nonetheless, various methods for achieving autoignition of methanol exist. To obtain stable combustion at all load points, a combination of techniques will be required. Pre-chamber technology, despite its lower maturity, holds promise for extending the knock limit and enhancing efficiency by acting as a distributed ignition source. Furthermore, mixing-controlled pre-chamber concepts show potential for eliminating knock and the associated size and power limitations. The review concludes by comparing each technology and identifying research gaps for future work. [ABSTRACT FROM AUTHOR]

To counter the rising threat of bacterial infections in the post-antibiotic age, intensive efforts are invested in engineering new materials with antibacterial properties. The key bottleneck in this initiative is the speed of evaluation of the antibacterial potential of new materials. To overcome this, we developed an automated pipeline for the prediction of antibacterial potential based on scanning electron microscopy images of engineered surfaces. We developed polymer composites containing graphite-oriented nanoplatelets (GNPs). The key property that the algorithm needs to consider is the density of sharp exposed edges of GNPs that kill bacteria on contact. The surface area of these sharp exposed edges of GNPs, accessible to bacteria, needs to be inferior to the diameter of a typical bacterial cell. To test this assumption, we prepared several composites with variable distribution of exposed edges of GNP. For each of them, the percentage of bacterial exclusion area was predicted by our algorithm and validated experimentally by measuring the loss of viability of the opportunistic pathogen Staphylococcus epidermidis. We observed a remarkable linear correlation between predicted bacterial exclusion area and measured loss of viability (R2 = 0.95). The algorithm parameters we used are not generally applicable to any antibacterial surface. For each surface, key mechanistic parameters must be defined for successful prediction. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Microscopic colitis (MC), encompassing collagenous colitis (CC) and lymphocytic colitis (LC), is a diagnosis which relies on histopathologic criteria. This report examines the validity of having a diagnosis of MC in Swedish pathology registers. METHODS: We reviewed patient charts from 215 randomly selected individuals from 15 pathology departments in five healthcare regions in Sweden with a relevant histopathology code for MC on colon biopsies. Information on clinical symptoms and laboratory data were obtained from medical chart review. We obtained sufficient data on 211 individuals for calculating positive predictive values (PPVs) for MC. RESULTS: In total, 200/211 patients with a histopathology diagnosis of MC were confirmed as also having a clinical diagnosis of MC after chart review, yielding a PPV of 95% (95%CI =91-97%). The PPV for CC was 95% (95%CI =87-98%) and 85% for LC (95%CI =78-90%). The median age at biopsy was 67 years (range 17-90 years), and 72% (n=154) were women. The most common symptoms in patients with MC histopathology were diarrhea (96% of patients), weight loss (24%) and abdominal pain (13%). Four percent (4/111) of patients with available data on stool culture were positive for gastrointestinal pathogens (none had Clostridium difficile). In 81 patients with available celiac serology, five (6%) were positive. Twenty-six percent of all patients had at least one other autoimmune disease, the most frequent being hypothyroidism (8%) and celiac disease (6%). CONCLUSIONS: This study found a high validity for MC as recorded in Swedish pathology registers. [ABSTRACT FROM AUTHOR]

Ectomycorrhizal fungi (ECM), the symbiosis between a host plant and mycorrhizal fungi, has been shown to considerably influence the C and N flux between soil, the rhizosphere and plant in boreal forest ecosystems. However, ECM is either neglected or presented as an implicit, non-dynamic term in most ecosystem models which can potentially reduce their predictive power. In order to investigate the necessity of an explicit consideration of ECM in ecosystem models, we implemented the previous developed MYCOFON model into a detail process-based soil-plant-atmosphere model, CoupModel. MYCOFON explicitly describes the C and N fluxes between ECM and roots. This new Coup-Mycofon model approach (ECM explicit) is compared to two simpler model approaches, of which one contains ECM implicitly as an non-dynamic N uptake function (ECM implicit) and the other represents a version where plant growth has a constant N availability (nonlim). Parameter uncertainties are quantified by using Bayesian calibration where the model outputs are constrained to current forest growth and soil conditions for four forest sites along a climate and N deposition gradient in Sweden over 100 year period. Our results show that the nonlim approach could not describe both the forest growth and soil C and N conditions properly. The ECM implicit/explicit approach is able to describe current conditions with acceptable uncertainty. The ECM explicit Coup-Mycofon model provide a more detailed description of internal ecosystems fluxes and feedbacks of C and N fluxes between plant, soil and ECM. Our modelling highlights the need of incorporating ECM in current ecosystem models. We also provide a key set of posterior fungal parameters which can be further investigated and evaluated in future ECM studies. [ABSTRACT FROM AUTHOR]

The CoupModel was used to simulate a Norway spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data a "vegetation fitted" model was obtained by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the spruce forest carbon (C) uptake, 413 g Cm-2 yr-1 and the decomposition of peat soil, 399 gCm-2 yr-1. N2O emissions contribute to the GHG emissions by up to 0.7 gNm-2 yr-1, corresponding to 76 g Cm-2 yr-1. The 60-year old spruce forest has an accumulated biomass of 16.0 kg Cm-2 (corresponding to 60 kgCO2 m-2). However, over this period, 26.4 kg Cm-2 (97 kgCO2eqm-2) has been added to the atmosphere, as both CO2 and N2O originating from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere. [ABSTRACT FROM AUTHOR]

High Nitrous Oxide (N 2 O) emissions have been identified in hemiboreal forests in association with draining organic soils. However, the specific controlling factors that regulate the emissions remain unclear. To examine the importance of different factors affecting N 2 O emissions in a spruce forest on drained organic soil, a process-based model, CoupModel, was calibrated using the generalized likelihood uncertainty estimation (GLUE) method. The calibration also aims to estimate parameter density distributions, the covariance matrix of estimated parameters and the correlation between parameters and variables information, useful when applying the model on other peat soil sites and for further model improvements. The calibrated model reproduced most of the high resolution data (total net radiation, soil temperature, groundwater level, net ecosystem exchange, etc.) very well, as well as cumulative measured N 2 O emissions (simulated 8.7 ± 1.1 kg N 2 O ha −1 year −1 ( n = 97); measured 8.7 ± 2.7 kg N 2 O ha −1 year −1 ( n = 6)), but did not capture every measured peak. Parameter uncertainties were reduced after calibration, in which 16 out of 20 parameters changed from uniform distributions into normal distributions or log normal distributions. Four parameters describing bypass water flow, oxygen diffusion and soil freezing changed significantly after calibration. Inter-connections and correlations between many calibrated parameters and variables reflect the complex and interrelated nature of pedosphere, biosphere and atmosphere interactions. This also highlights the need to calibrate a number of parameters simultaneously. Model sensitivity analysis indicated that N 2 O emissions during growing seasons are controlled by competition between plants and microbes for nitrogen, while during the winter season snow melt periods are important. Our results also indicate that N 2 O is mainly produced in the capillary fringe close to the groundwater table by denitrification in the anaerobic zone. We conclude that, in afforested drained peatlands, the plants and groundwater level have important influences on soil N availability, ultimately controlling N 2 O emissions. [ABSTRACT FROM AUTHOR]