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This paper aims to review the role of Panicum miliaceumcultivation in the Late Bronze Age within present-day Denmark. An archaeobotanical analysis of a recently discovered assemblage of charred remains, including a larger proportion of millet, functions as an onset for the investigation. A contextual approach at the site level is used to discuss the importance and presence of P. miliaceumwithin the social environment of this period. Furthermore, radiocarbon dates of P. miliaceumgrains from Arnbjerg N reveal insight into the absolute chronology of P. miliaceumwithin the region.

Pure low density polyethylene pyrolysis was investigated using a lab-scale two-stage fixed-bed pyrolyzer with different catalytic materials in the second reactor for upgrading the vapors. The yields of gas and char were determined, and the condensed product was thoroughly examined by gas chromatography–mass spectrometry and thermogravimetric analysis. The use of different catalytic materials such as HZSM-5, cement raw meal, calcined cement raw meal, and silicon carbide was investigated. A wax-rich condensed product (intermediate molecular weight hydrocarbons) was observed in the following types of experiments: no catalyst, silicon carbide, and cement raw meal in the second reactor. The wax was mainly composed of alkanes and alkenes. The use of an HZSM-5 catalyst and applying temperatures from 350 to 500 °C in the second reactor highly decreased the chain length of hydrocarbons in the condensed product and converted the wax into a liquid. When the second reactor temperature was higher than 400 °C, the main product components were aromatics and naphthalene. Using calcined raw meal in the second reactor at a temperature of 600 °C also led to the conversion of the wax to a liquid product with a large fraction of cyclic aliphatics.

Background: Currently, bariatric surgery is the most effective long-term treatment of obesity. Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) are the primary types of bariatric surgery performed worldwide. To minimize the risks of surgical complications and optimize cost-effectiveness, it is essential to develop fast-track protocols and patient logistics. At Aleris Hospitals in Denmark, a fast-track methodology in bariatric surgery has been implemented and continuously optimized over the last 15 years. The main objective was to demonstrate timelines recorded during one consecutive year in a fast-track, high-volume bariatric surgery setting after logistic optimization. Methods: This study included 949 consecutive patients who had undergone primary bariatric surgery in 2021. The primary outcomes were length of hospital stay and perioperative timeline recordings that were prospectively collected. The secondary outcomes were mortality, complication rates, and weight loss data. Results: The vast majority of our patients (99.1%) were discharged from the hospital within the day after surgery. The median total surgery time was 30 min, after 12 min of patient preparation and with a turnover time between patients of seven min. The median knife-to-knife time in one operating room was 56 min. Mortality was zero, 30-day reoperation rate was 1.2%, and 30-day readmission rate was 0.8%. SG and RYGB patients had an excess weight loss after four months of 45.6% and 57.9%, respectively. Conclusion: Implementation of fast-track principles in the clinical practice of bariatric surgery allows for an optimized, cost-effective surgical organization supporting the quality of procedures and patient safety. Graphical abstract:

This study investigates the influence of wood pellet properties on the grindability of pellets in a lab-scale disc mill. The pellet properties investigated included wood type, moisture content, internal pellet particle size distribution, particle density, and durability. Two pellet qualities for industrial use (designated I1 and I2 as per ISO 17225-2:2014) and two types of semi-industrial pellets (beech and pine) were used and grinding was performed on as-received and oven-dried pellets. The grinding performance was assessed by measuring the grinding energy and analyzing the changes in particle morphology (size and shape) with respect to the internal pellet particle morphology. Von Rittinger’s comminution law was used to characterize the pellet grindability. Drying pellets increased their brittleness and improved their grindability, resulting in both grinding energy savings and a higher milled product fineness, and the impact of drying was larger for industrial pellets. Beech pellets had a better grindability (kWh mm t-1dry wood) than pine pellets (kWh mm t-1dry wood). The moisture content of pellets did not influence the shape of the milled particles in terms of circularity and elongation ratio. The study also showed that the proposed disc mill has the potential to quickly determine the relative grindability characteristics of various pellet qualities.

The value proposition (VP) is the core element that makes any business model viable. This also applies to circular business models that promote slower consumption cycles and longer active product longevity. However, specific guidelines, strategies and recommendations for designing VPs that can prolong the product lifetime are lacking. Moreover, there is a need for strategies that have proven to work in practice, as research shows several examples of products with new circular VPs that are rejected by the customer when they are implemented. This study explores how 17 best practice companies approached the longevity challenge to create long-term VPs, based on framing and reframing theory from innovation literature. The study results in seven reframing strategies that suggest alternative ways to approach the design of VPs that promote product longevity. Hence, the study contributes with some much-needed input regarding practical and applicable strategies to create superior or unique customer experience that prolong product lifetimes.

Graphical Abstract:

Barnyard grass [Echinochloa crus‐galli(L.) Beauv] is a competitive C4weed species that is widely distributed throughout the world. Although it originated in warm climatic conditions, currently, it is found in Europe as far north as Norway. This study aimed to compare the phenological development of plants from different climatic conditions in varying environmental conditions. To represent the contrasting climatic conditions within Europe, seeds were collected in Norway and Italy, and distributed to the study participants, to be sown at 10 different sites as two common populations. In addition to that, seeds of two to three local populations were collected near each of the sites. The development of the plants was monitored in a pot experiment set up under field conditions. The time to reach heading in the first year of the experiment was 77.6% faster (ranging from 45.9 to 98.3% on average) in the Norwegian than in the Italian population. However, in the leaf development stage, the difference between the common populations was smaller by, 23.5% on average (0–46.7%) and was mostly not significant. Our results indicate that different E. crus‐galliecotypes, characterized by differences in their phenological development, evolved within the distribution area of this species in Europe. However, the early development of the plants progressed with negligible differences between populations. The findings reported here can be used to adapt existing models from one region to regions with different climatic conditions for use in decision support systems and for research into plant population dynamics. Different ecotypes of barnyard grass have developed in southern and northern populations.In northern populations heading occurs earlier than in southern populations.Vegetative development is similar in different populations.

•Charred plant remains show an increase in food resources in Iron Age Denmark.•Stable isotopes show consistent soil enrichment in fields of barley.•Agriculture seems resilient to climatic fluctuations during the Iron Age.

BackgroundA basic paradigm of human infection is that acute bacterial disease is caused by fast growing planktonic bacteria while chronic infections are caused by slow-growing, aggregated bacteria, a phenomenon known as a biofilm. For lung infections, this paradigm has been thought to be supported by observations of how bacteria proliferate in well-established growth media in the laboratory—the gold standard of microbiology.ObjectiveTo investigate the bacterial architecture in sputum from patients with acute and chronic lung infections.MethodsAdvanced imaging technology was used for quantification and direct comparison of infection types on fresh sputum samples, thereby directly testing the acute versus chronic paradigm.ResultsIn this study, we compared the bacterial lifestyle (planktonic or biofilm), growth rate and inflammatory response of bacteria in freshly collected sputum (n=43) from patient groups presenting with acute or chronic lung infections. We found that both acute and chronic lung infections are dominated by biofilms (aggregates of bacteria within an extracellular matrix), although planktonic cells were observed in both sample types. Bacteria grew faster in sputum from acute infections, but these fast-growing bacteria were enriched in biofilms similar to the architecture thought to be reserved for chronic infections. Cellular inflammation in the lungs was also similar across patient groups, but systemic inflammatory markers were only elevated in acute infections.ConclusionsOur findings indicate that the current paradigm of equating planktonic with acute and biofilm with chronic infection needs to be revisited as the difference lies primarily in metabolic rates, not bacterial architecture.

Chronic infections caused by microbial biofilms represent an important clinical challenge. The recalcitrance of microbial biofilms to antimicrobials and to the immune system is a major cause of persistence and clinical recurrence of these infections. In this Review, we present the extent of the clinical problem, and the mechanisms underlying the tolerance of biofilms to antibiotics and to host responses. We also explore the role of biofilms in the development of antimicrobial resistance mechanisms.

By use of coal fly ash as an additive in pulverized biomass fuel boilers, harmful alkali species can be bound in alkali alumina silicates that are less harmful. In this study, potassium scavenging by coal fly ash (CFA) at conditions of pulverized-fuel (PF) boilers was modeled. Under the investigated conditions, evaporated potassium salts were captured with suspended CFA particles. Two modeling approaches were investigated, shrinking core model (SCM) and uniform conversion model (UCM). Both approaches simulated the impacts of chemical kinetics, diffusion of gaseous salts around the additive particles, and thermodynamic equilibrium on potassium conversion. Moreover, the SCM included the diffusion resistance in a product layer around the particle. The models have been evaluated against entrained flow-reactor (EFR) measurements from the literature for capturing KOH, KCl, K2CO3, and K2SO4by CFA. Chemical kinetic rate coefficients for the reaction between the potassium salts and CFA have been derived from the EFR data measured at relatively lower temperatures of 800–900 °C. The porosity properties of the reacted CFA were also estimated in the present work. The effects of temperature, salt concentration, and CFA particle size on the model prediction have been examined and evaluated against the experimental data. The results indicated that in most conditions, the SCM prediction is more reliable, probably due to the inclusion of diffusion resistance of a product layer around the particle. Comparing the SCM with experimental data shows that the model can reasonably predict the reaction of CFA with potassium salts at conditions investigated here: 800–1450 °C, salt to additive ratios of 0.05–0.96, and for CFA particles of 6–34 μm.

Necrotizing soft-tissue infection (NSTI) is a rare, severe, and fast-progressing bacterial infection associated with a high risk of developing sepsis or septic shock. Increasing evidence indicates that oxidative stress is crucial in the development and progression of sepsis, but its role in NSTI specifically has not been investigated. Some patients with NSTI receive hyperbaric oxygen (HBO2) treatment as the restoration of oxidative stress balance is considered an important mechanism of action, which HBO2facilitates. However, a gap in knowledge exists regarding the effect of HBO2treatment on oxidative stress in patients with NSTI. In the present observational study, we aimed to investigate HBO2treatment effects on known markers of oxidative stress in patients with NSTI. We measured plasma myeloperoxidase (MPO), superoxide dismutase (SOD), heme oxygenase-1 (HO-1) and nitrite+nitrate in 80 patients with NSTI immediately before and after their first HBO2treatment, and on the following day. We found that HBO2treatment was associated with a significant increase in MPO and SOD by a median of 3.4 and 8.8 ng/mL, respectively. Moreover, we observed an HBO2treatment-associated increase in HO-1 in patients presenting with septic shock (n=39) by a median of 301.3 pg/mL. All markers were significantly higher in patients presenting with septic shock compared to patients without shock, and all markers correlated with disease severity. High baseline SOD was associated with 90-day mortality. In conclusion, HBO2treatment was associated with an increase in MPO and SOD in patients with NSTI, and oxidative stress was more pronounced in patients with septic shock.

Ash deposition on boiler surfaces is a major problem encountered in biomass combustion. Timely removal of ash deposits is essential for optimal boiler operation. In order to improve the understanding of deposit shedding in boilers, this study investigates the adhesion strength of biomass ash from full-scale boilers, as well as model fly ash deposits containing KCl, K2SO4, CaO, CaSO4, SiO2, K2CO3, Fe2O3, K2Si4O9, and KOH. Artificial biomass ash deposits were prepared on superheater tubes and sintered in an oven with temperatures ranging from 500 to 1000 °C. Subsequently, the deposits were sheared off by an electrically controlled arm, and the corresponding adhesion strength was measured. The effect of sintering temperature, sintering time, deposit composition, thermal shocks on the deposit, and steel type was investigated. The results reveal that the adhesion strength of ash deposits is dependent on two factors: ash melt fraction, and corrosion occurring at the deposit–tube interface. Adhesion strength increases with increasing sintering temperature, sharply increasing at the ash deformation temperature. However, sintering time, as well as the type of steel used, does not have a significant effect under the investigated conditions. Addition of compounds which increase the melt fraction of the ash deposit, typically by forming a eutectic system, increases the adhesion strength, whereas addition of inert compounds with a high melting point decreases the adhesion strength. Furthermore, the study indicated that sulfation of ash deposits leads to an increase in adhesion strength, while cooling down the deposits after sintering decreases the adhesion strength. Finally, it was observed that adhesion strength data follow a log-normal distribution.

The objective of this work was to generate comprehensive data on the formation of residual fly ash during the initial stages of suspension firing of biomass. Combustion experiments were carried out with pulverized biomass fuels (two straw fuels and two wood fuels), in an entrained flow reactor at 1200–1400 °C, simulating full-scale suspension firing of biomass. By the use of a movable, cooled, and quenched gas/particle sampling probe, samples were collected at different positions along the vertical axis in the reactor, corresponding to gas residence times ranging from 0.25 to 2.0 s. The collected particles were subjected to various analyses, including char burnout level, particle size distribution, elemental composition, and particle morphology and composition. Furthermore, the transient release, i.e., the vaporization of the flame-volatilized inorganic elements K, Cl, and S, from the burning fuel particles to the gas phase, has been quantified using two different calculation methods. The ash formation mechanisms were found to be quite similar for straw and wood. The degree of conversion (char burnout level) was generally good at residence times of ≥1 s. The size distribution of the residual fly ash particles evolved with the residence time. For all ashes at long residence times, a peak of residual ash particles in the range of 20–100 μm was observed. The residual ash particles were rich in Si, K, and Ca. Further, at long residence times, sub-micrometer particles consisting primarily of KCl (condensed aerosols) became abundant in the ashes from straw combustion. Release of K to the gas phase was nearly 100% for the two wood fuels and one of the straw fuels. A straw sample (straw 2) with a high Si/K molar ratio and relative shortage of Ca showed a limited release of K in the range of 65%; this suggests larger retention of K in Si-rich, Ca-lean fuels as a result of incorporation of K into silicate structures. All S and Cl were nearly completely released to the gas phase for all studied samples.

Nisin is commonly used as a biopreservative in foods. For industrial production, nisin-producing Lactococcus lactisstrains are usually grown to high cell densities to achieve the highest possible nisin titer. However, accumulation of lactic acid eventually halts production, even in pH-controlled fermentations. Here, we describe a nisin-producing L. lactisstrain Ge001, which was obtained after transferring the nisin gene cluster from L. lactisATCC 11454, by conjugation, into the natural mutant L. lactisRD1M5, with low lactate dehydrogenase activity. The ability of Ge001 to produce nisin was tested using dairy waste as the fermentation substrate. To accommodate redox cofactor regeneration, respiration conditions were used, and to alleviate oxidative stress and to reduce adsorption of nisin onto the producing cells, we found it to be beneficial to add 1 mM Mn2+and 100 mM Ca2+, respectively. A high titer of 12 084 IU/mL nisin could be reached, which is comparable to the highest titers reported using expensive, rich media. Summing up, we here present a 100% natural, robust, and sustainable approach for producing food-grade nisin and acetoin from readily available dairy waste.

Necrotizing soft-tissue infection (NSTI) is a rare, severe, and fast-progressing bacterial infection associated with a high risk of developing sepsis or septic shock. Increasing evidence indicates that oxidative stress is crucial in the development and progression of sepsis, but its role in NSTI specifically has not been investigated. Some patients with NSTI receive hyperbaric oxygen (HBO2) treatment as the restoration of oxidative stress balance is considered an important mechanism of action, which HBO2facilitates. However, a gap in knowledge exists regarding the effect of HBO2treatment on oxidative stress in patients with NSTI. In the present observational study, we aimed to investigate HBO2treatment effects on known markers of oxidative stress in patients with NSTI. We measured plasma myeloperoxidase (MPO), superoxide dismutase (SOD), heme oxygenase-1 (HO-1) and nitrite+nitrate in 80 patients with NSTI immediately before and after their first HBO2treatment, and on the following day. We found that HBO2treatment was associated with a significant increase in MPO and SOD by a median of 3.4 and 8.8 ng/mL, respectively. Moreover, we observed an HBO2treatment-associated increase in HO-1 in patients presenting with septic shock (n=39) by a median of 301.3 pg/mL. All markers were significantly higher in patients presenting with septic shock compared to patients without shock, and all markers correlated with disease severity. High baseline SOD was associated with 90-day mortality. In conclusion, HBO2treatment was associated with an increase in MPO and SOD in patients with NSTI, and oxidative stress was more pronounced in patients with septic shock.

Supplemental Digital Content is available in the text.

Lactococcus lactissubsp. lactisbiovar diacetylactis is widely used in dairy fermentations as it can form the butter aroma compounds acetoin and diacetyl from citrate in milk. Here, we explore the possibility of producing acetoin from the more abundant lactose. Starting from a dairy isolate of L. lactisbiovar diacetylactis, we obtained a series of mutants with low lactate dehydrogenase (ldh) activity. One isolate, RD1M5, only had a single insertion mutation in the ldhgene compared to its parental strain as revealed by whole genome resequencing. We tested the ability of RD1M5 to produce acetoin in milk. With aeration, all the lactose could be consumed, and the only product was acetoin. In a simulated cheese fermentation, a 50% increase in acetoin concentration could be achieved. RD1M5 turned out to be an excellent cell factory for acetoin and was able to convert lactose in dairy waste into acetoin with high titer (41 g/L) and high yield (above 90% of the theoretical yield). Summing up, RD1M5 was found to be highly robust and to grow excellently in milk or dairy waste. Being natural in origin opens up for applications within dairies as well as for safe production of food-grade acetoin from low-cost substrates.

Char and soot characterization was performed on samples obtained from pilot-scale entrained flow gasification of coal bio-oil slurry (CBS) and coal/water slurry (CWS) at different operating conditions. The compositions and gasification reactivity of char and soot have been investigated to reveal the difference of CBS and CWS slurries. The results show that both char and soot obtained from CBS gasification contain alkali and alkaline earth metals which come from the bio-oil. These CBS char and soot alkali-containing samples exhibit higher gasification reactivity than those from CWS gasification. For CBS gasification, soot has higher gasification reactivity compared with char. The gasification reactivity may be caused by the catalytic effect of KCl and K2SO4existing in char and soot. The reactivity of char and soot is also influenced by the gasification conditions (such as H2O/C ratio), and high CO2gasification reactivity is observed for chars exposed to high H2O/C ratios in the entrained flow reactor.

Mannitol can be obtained as a by-product of certain heterolactic lactic acid bacteria, when grown on substrates containing fructose. Lactococcus lactis, a homolactic lactic acid bacterium, normally does not form mannitol but can be persuaded into doing so by expressing certain foreign enzyme activities. In this study, we find that L. lactishas an inherent capacity to form mannitol from glucose. By adaptively evolving L. lactisor derivatives blocked in NAD+regenerating pathways, we manage to accelerate growth on mannitol. When cells of the adapted strains are resuspended in buffer containing glucose, 4–58% of the glucose metabolized is converted into mannitol, in contrast to nonadapted strains. The highest conversion was obtained for a strain lacking all major NAD+regenerating pathways. Mannitol had an inhibitory effect on the conversion, which we speculated was due to the mannitol uptake system. After its inactivation, 60% of the glucose was converted into mannitol by cells suspended in glucose buffer. Using a two-stage setup, where biomass first was accumulated by aerated culturing, followed by a nonaerated phase (static conditions), it was possible to obtain 6.1 g/L mannitol, where 60% of the glucose had been converted into mannitol, which is the highest yield reported for L. lactis.

Up to 40% of adults over 65 years are full-time users of absorbent incontinence pads due to urinary incontinence. Simultaneously, urinary tract infection is amongst the most common hospital-acquired infection in older patients.

Pulverized biomass may self-heat and spontaneously ignite when stored or processed at intermediate or even low temperatures. In this work, reaction kinetic parameters for biomass oxidation and pyrolysis were determined for the temperature range 423–523 K. Thermogravimetric analysis was used to determine mass loss kinetics in a stepwise-isothermal heating program. Two wood species (pine and beech), two agricultural residues (wheat straw and sunflower husks), and two commercial wood pellet samples were investigated. Atmospheres with 0, 20, and 80% oxygen were used in the experiments. A pyrolysis model of four parallel reactions for extractives, hemicellulose, cellulose, and lignin fit the experimental data for 0% O2well. Oxidation kinetics could be modeled by additional reactions in parallel to the pyrolysis mechanism. Two mechanisms were tested: (1) considering oxidation of a lumped “volatilizable” component plus oxidation of char; and (2) separate oxidation reactions for volatilizable extractives, hemicellulose, cellulose, and lignin, plus char. The more complex mechanism did not give a clear advantage over the simpler mechanism. It was further found that pyrolysis and oxidation reactions for the components could be modeled with the same activation energy, regardless of which biomass they appear in. For the lumped component oxidation model, an apparent activation energy of 130 kJ/mol was found. The observed reaction order in oxygen was in the range 0.4–0.5. The models also compared favorably to additional experimental data between 373 and 773 K for a heating rate of 5 K/min. The kinetic models presented here are intended mainly to describe low-temperature reactions, such as self-heating of biomass and the onset of smoldering combustion.

HZSM-5 extrudates, its two constituents (HZSM-5 zeolite and alumina binder), and SiC for reference were tested after steam treatment for the upgrading of wheat straw fast pyrolysis (FP) vapors from an ablative bench scale system. In addition, mesoporosity was added to the HZSM-5 crystals of the zeolite/Al2O3extrudates by desilication, which decreased the microporous volume and led to enhanced weak acidity and less strong acidity compared to the parent extrudates. For increasing biomass-to-catalyst ratios (w/w, B:C), oils were collected and analyzed for elemental composition, total acid number (TAN), moisture, molecular weight, evaporation characteristics, and chemical composition by gas chromatography–mass spectrometry with flame ionization detection (GC-MS/FID), 1H nuclear magnetic resonance (NMR), 13C NMR, and two-dimensional heteronuclear single-quantum correlation (2D HSQC) NMR. Compared to Al2O3, catalysts containing HZSM-5 promoted aromatization and limited the coke formation due to its shape selective micropores. Nevertheless, Al2O3was effective in deoxygenation. At B:C ∼7, 23 wt % carbon/25% energy recovery in the oil fraction was obtained while reducing the oxygen content by 45% relative to a thermal reference oil fraction obtained over a SiC bed. As such, Al2O3offers certain benefits compared to HZSM-5-based catalysts due to its lower cost and better hydrothermal stability with respect to acidity. At a catalyst temperature of 500 °C, the introduction of mesopores to HZSM-5 extrudates led to higher energy recovery as oil compared to the parent HZSM-5 extrudates. At B:C = 6.3, 24 wt % carbon/26% energy recovery in the oil phase was achieved while removing 45% of the oxygen functionalities relative to the thermal reference bio-oil. Compared to deep deoxygenation for direct hydrocarbon production, mild deoxygenation improved the energy recoveries of the oil fractions and appears viable for pretreating pyrolysis vapors before co-processing bio-oils with fossil oil in refineries.

Lactose, the sugar contained in milk, has a low sweetness. We have constructed an efficient whole-cell catalyst (WCC) that can be grown on dairy waste and that is able to convert lactose into a mixture of sugars as sweet as sucrose. The WCC is based on Corynebacterium glutamicumATCC13032, which has been engineered to metabolize lactose, to express xylose and arabinose isomerase, and to eliminate byproduct formation. When introduced in concentrated cheese whey permeate, its content of 98 g/L lactose was completely hydrolyzed and the liberated sugars partially isomerized into 23.5 g/L fructose and 20.4 g/L tagatose, which corresponds to a 49% conversion of the glucose and a 44% conversion of galactose. The latter is similar to what can be obtained using purified enzymes. The new technology enables better resource utilization and allows for dairy waste to be converted into a valuable food sweetener with many potential uses.