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Paludiculture (crop cultivation on wet peatlands) is an effective means to reduce carbon emissions and nutrient losses from formerly drained peatlands. However, methane (CH4) emissions and associated pathways may vary substantially between paludicultures, depending on the cultivated paludicrop. Whereas many studies have investigated diffusive CH4 emissions from paludicrops, large uncertainties exist in relation to the importance of CH4 ebullition, species-specific differences and seasonal dynamics. In this study we aimed to quantify CH4 emissions from stands of three paludicrop species, namely Typha latifolia, Typha angustifolia and Azolla filiculoides. CH4 diffusive fluxes - including plant-mediated emissions - and ebullitive fluxes were studied year-round on a rewetted former agricultural peatland in The Netherlands. Additionally, we tested the effect of irrigation strategy (water table depth) and nutrient loading on CH4 emissions from stands of both Typha species. Diffusive CH4 emissions were lowest from A. filiculoides stands (average 15.4 ± 6.6 mg m-2 d-1), followed by open water (36.4 ± 6.0 mg m-2 d-1). Substantially higher diffusive emissions were measured for both Typha species, with the highest emissions in T. latifolia (187.0 ± 29.4 mg m-2 d-1). Ebullitive fluxes were generally low (< 100 mg m-2 d-1), but the highest ebullitive fluxes occurred in the A. filiculoides stand, contributing 79 % on average to its total CH4 emissions. A water table just below the peat surface substantially reduced Typha CH4 emissions, but also led to lower biomass production, compared to a flooded (+20 cm) water table. Nutrient loading increased biomass production and did not affect diffusive CH4 emissions. Our results underline that species choice substantially affects paludiculture carbon dynamics in the first phase after establishment. Quantifying both diffusive and ebullitive fluxes is of paramount importance in adequately assessing paludiculture CH4 fluxes.

IntroductionRemyelination of demyelinated axons can occur as an endogenous repair mechanism in multiple sclerosis (MS), but its efficacy varies between both MS individuals and lesions. The molecular and cellular mechanisms that drive remyelination remain poorly understood. Here, we studied the relation between microglia activation and remyelination activity in MS.MethodsWe correlated regenerative (CD163+) and inflammatory (iNOS+) microglia with BCAS1+ oligodendrocytes, subdivided into early-stage (

Although student engagement is known to promote learning outcomes in higher education, what elements of blended learning designs impact effective student engagement and hereby learning outcomes, has not been clarified yet. Hence, it is unknown how to engage students with blended learning in an effective manner. The current study breaks down student engagement into four dimensions (academic, behavioral, cognitive, and affective), and reviews the evidence regarding blended learning that engages students effectively, whether this is academically, personally, socially, or with regard to citizenship. The studies reviewed (k = 15, N = 1,428) overall asserted that all blended learning interventions investigated had a moderate to high impact on student engagement and on learning outcomes. This review, a summary and insight into the evidence, is important for the field's understanding as well as for professionals in higher education: for lecturers and policy makers who want to introduce and monitor blended learning as a means to promote both student engagement and their learning outcomes in higher education. Further research is required to increase our knowledge of how blended learning impacts both multi-dimensional constructs: student engagement and learning outcomes.

Rewetting drained peatlands for paludiculture purposes is a way to reduce peat oxidation (and thus CO2 emissions) while at the same time it could generate an income for landowners, who need to convert their traditional farming into wetland farming. The side effect of rewetting drained peatlands is that it potentially induces high methane (CH4) emissions. Topsoil removal could reduce this emission due to the removal of easily degradable carbon and nutrients. Another way to limit CH4 emissions is the choice in paludiculture species. In this study we conducted a field experiment in the coastal area of the Netherlands, in which a former non-intensively used drained peat grassland is rewetted to complete inundation (water table ∼ +18 cm) after a topsoil removal of ∼ 20 cm. Two emergent macrophytes with high potential of internal gas transport (Typha latifolia and Typha angustifolia), and a free floating macrophyte (Azolla filiculoides), were introduced and intensive measurement campaigns were conducted to capture CO2 and CH4 fluxes as well as soil and surface water chemistry. Greenhouse gas fluxes were compared with a high-productive peat meadow as a reference site. Topsoil removal reduced the amount of phosphorus and iron in the soil to a large extent. The total amount of soil carbon per volume stayed more or less the same. The salinity of the soil was in general high, defining the system as brackish. Despite the topsoil removal and salinity, we found very high CH4 emissions for T. latifolia (84.8 g CH4 m−2 yr−1) compared with the much lower emissions from T. angustifolia (36.9 g CH4 m−2 yr−1) and Azolla (22.3 g CH4 m−2 yr−1). The high emissions can be partly explained by the large input of dissolved organic carbon into the system, but it could also be caused by plant stress factors like salinity level and herbivory. For the total CO2 flux (including C-export), the rewetting was effective, with a minor uptake of CO2 for Azolla (−0.13 kg CO2 m−2 yr−1) and a larger uptake for the Typha species (−1.14 and −1.26 kg CO2 m−2 yr−1 for T. angustifolia and T. latifolia, respectively) compared with the emission of 2.06 kg CO2 m−2 yr−1 for the reference site. T. angustifolia and Azolla, followed by T. latifolia, seem to have the highest potential for reducing greenhouse gas emissions after rewetting to flooded conditions (−1.4, 2.9, and 10.5 t CO2 eq. ha−1 yr−1, respectively) compared with reference drained peatlands (20.6 t CO2 eq. ha−1 yr−1). When considering the total greenhouse gas balance, other factors, such as biomass use and storage of topsoil after removal, should be considered. Especially the latter factor could cause substantial carbon losses if not kept in anoxic conditions. When calculating the radiative forcing over time for the different paludicrops, which includes the GHG fluxes and the carbon release from the removed topsoil, T. latifolia will start to be beneficial in reducing global warming after 93 years compared with the reference site. For both Azolla and T. angustifolia this will be after 43 years.

IntroductionDrainage for agricultural purposes is one of the main drivers of peatland degradation, leading to significant greenhouse gas (GHG) emissions, biodiversity loss, and soil eutrophication. Rewetting is a potential solution to restore peatlands, but it generally requires a land-use shift to paludiculture or nature areas.MethodsThis study explored whether three different water level management techniques (subsoil irrigation, furrow irrigation, and dynamic ditch water level regulation) could be implemented on dairy grasslands to yield increases in essential ecosystem services (vegetation diversity and soil biogeochemistry) without the need to change the current land use or intensity. We investigated vegetation diversity, soil biogeochemistry, and CO2 emission reduction in fourteen agricultural livestock pastures on drained peat soils in Friesland (Netherlands).ResultsAcross all pastures, Shannon-Wiener diversity was below 1, and the species richness was below 5. The plant-available phosphorus (P) was consistently higher than 3 mmol L−1. None of the water level management (WLM) techniques enhanced vegetation diversity or changed soil biogeochemistry despite a notable increase in water table levels. The potential for CO2 emission reduction remained small or even absent. Indicators of land-use intensity (i.e., grass harvest and fertilization intensity), however, showed a strong negative correlation with vegetation diversity. Furthermore, all sites’ total and plant-available P and nitrate exceeded the upper threshold for species-rich grassland communities.DiscussionIn conclusion, our research suggests that incomplete rewetting (i.e., higher water tables while maintaining drainage) while continuing the current land use does neither effectively mitigate GHG emissions nor benefit vegetation diversity. Therefore, we conclude that combining WLM and reducing land-use intensity is essential to limit the degradation of peat soils and restore more biodiverse vegetation.

Following the implementation of food safety limits on cadmium (Cd) in cacao products, there has been a growing demand for monitoring Cd in cacao tissues and soils. Traditional methods like acid digestion followed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are time-consuming and costly. X-ray Fluorescence is an alternative technique that offers advantages in terms of speed, cost, ease of use and less environmental impact. However, to date, relatively high detection limits have impeded its application for food safety limits. This study examines a Monochromatic Energy Dispersive X-ray Fluorescence (MEDXRF) method optimized for Cd analysis as an alternative to ICP-MS. Using a measurement time of 200 s, the average limit of quantification (LOQ) was 0.178 mg Cd kg−1 for biological samples and 0.205 mg Cd kg−1 for soil samples. A strong correlation (y = 1.013 x + 0.003, R2 = 0.984) with ICP-MS results was found for 95 bean, 16 cacao liquor, 75 leaf, and 91 soil samples. The coefficient of variation (CV) among three replicates was below the threshold value of 15 % for most samples with Cd concentrations above the reported LOQ values. Additionally, a significant difference in CV was obtained between soils sieved over 500 μm (median 8.2 %) or 2 mm (median 9.8 %). However, no significant difference in CV was observed between 500 μm unpeeled beans and cocoa liquor with particle size of 20 μm. Based on our data, the proposed procedure is to analyze three replicates for 200 s with a sample size of 500 μm. The optimized MEDXRF technique offers important advantages in terms of cost-effectiveness and efficiency of routine Cd monitoring in the cacao supply chain, large-scale screening, and scientific research, and could be extended to other crops and heavy metals that are subject to food safety regulation at low concentrations.

In this case report, we describe an extramedullary plasmacytoma (EMP) of the trachea in a 74-year-old female. She presented with a subglottic stenosis that causes 70% obstruction of the subglottis and severe dyspnea since 3 months. A flexible laryngoscopy was performed and showed a subglottis stenosis grade 3. Magnetic resonance imaging neck revealed an endoluminal mass at the level of the proximal trachea with full obliteration of the lumen. A biopsy was performed and the histopathological study identified a plasma cell neoplasm or a plasmacytoma with a kappa light chain restriction. After direct laryngoscopy with biopsy, the dyspnoea worsened, and a tracheotomy was performed. Localised radiotherapy of the trachea was started with complete remission. One month after radiation therapy, the EMP was reduced in size and the tracheostomy tube could be decannulated. Three weeks later the lumen of the tracheostomy was closed. Three months after treatment, the patient is still in good condition. Extramedullary plasmacytomas of the trachea are extremely rare tumors but should be considered as a differential diagnosis in the workup of a tracheal tumor. The treatment of choice is radiation therapy. Annual follow-up and evaluation of local recurrence or possible progression to malignant melanoma is mandatory.

Study Design: This is an observational study. Objectives: In general practice, it is noted that some people can deal more easily with a prominent belly than others. Recent use of spinopelvic parameters in the analysis of the spine might explain this observation. This study aimed to determine the correlation between pelvic incidence (PI), waist circumference (WC), and body mass index (BMI) in patients with non-specific chronic low back pain. We hypothesized that people with a low PI (non-pronounced lumbar lordosis) have significantly lower WC values than those with a high PI (pronounced lumbar lordosis). Methods: Adult patients presenting to the outpatient neurosurgery clinic with non-specific chronic low back pain who had undergone full spine radiography were included. The PI, BMI, and WC were measured in all cases. Results: We included 272 patients (male–female ratio, 1.08) with a mean age of 54 years. There was a statistically significant difference (p < 0.05) in the mean PI according to BMI group. The mean PI in our population was 57.8° (range 28.4–97.2°, SD 12.1°). A significant correlation coefficient of 0.271 (p < 0.001; 95%CI 0.157–0.377) was found between BMI and PI and 0.410 (p-value < 0.001; 95%CI 0.262–0.539). Conclusions: We found a significant correlation between PI, BMI, and WC. This finding is the first step in confirming our hypothesis that a patient with a high PI might be able to tolerate being overweight and a high WC better than patients with a low PI, possibly because of their ability to retrovert the pelvis to a greater extent. Further research is warranted to investigate whether people with a high pelvic PI can better cope with obesity, especially those with a higher waist circumference and abdominal weight.

This study presents a multiproxy palaeodemographic perspective by combining radiocarbon dates with counts of archaeological site phases in the western Scheldt basin, spanning from the beginning of the Neolithic to the Early Bronze Age. The results were assessed critically, accounting for differences in research methodology, soil conditions and changes in building traditions. The results indicate a dynamic region characterized by almost continual growth. Moreover, two distinct sub-regions of the basin could be compared, thereby elucidating the sub-regional differences. It is clear that palaeodemographic studies are only feasible when a multiproxy analysis is used on a detailed, highly scrutinized dataset.

Studying the fate of phosphorus (P) around the soil-fertilizer interface is crucial for developing efficient fertilizers. Here, a method is developed to map P dissolution from granules into flooded soil with due attention to avoid oxidation artifacts during monitoring. The method of diffusive gradient in thin films (DGT) technique was used in soil incubated under flooded conditions; the P concentration in the DGT was visualized with colorimetry. The diffusion zone around the granule was monitored by repeatedly deploying DGTs with precipitated Zr oxide-based binding gels on the soil surface for 24 h in an anaerobic chamber. The soil surface was opened at various periods after flooding (1–42 days) and after removing the water and a 1 cm upper soil layer, thereby leaving a soil layer with a fixed depth above the embedded fertilizer. The method was developed after testing the effects of DGT deployment time, the placement of DGT (below or above the granule), the fertilizer granule depth (1 cm or 0.4 cm) below the soil surface where the gel was deployed, and the mass of fertilizer granule. The final method was tested in three different P-deficient soils (acid, neutral, calcareous) incubated with granular soluble P fertilizer (triple superphosphate, TSP) under flooded conditions. In the highly P-sorbing acid soil, no diffusion zones were observed. In the other two soils with a lower P sorption capacity, the P diffusion zones in the gels were immediately observed after 1 d of incubation, highlighting the influence of soil properties on the fate of fertilizer P under flooded conditions. The technique developed here allows for a simple, non-destructive assessment of P behavior under flooded conditions and, hence, can be a valuable tool for improving P fertilizer formulations adapted to flooded soils and providing insights into the potential availability of fertilizer-P for plant uptake.

Excessive daytime sleepiness is a common symptom of sleep disorders. Despite its prevalence, it remains difficult to define, detect, and address. The difficulties surrounding sleepiness have been linked to an ambiguous conceptualization, a large variety of scales and measures, and the overlap with other constructs, such as fatigue. The present study aims to investigate patients’ descriptions of sleepiness-related daytime complaints and their phenomenology. We performed semi-directed interviews with patients diagnosed with obstructive sleep apnea (N = 15) or narcolepsy (N = 5). The interviewers took care of utilizing the participants’ terminology when describing daytime complaints related to their sleep disorder. Various aspects of the daytime complaints were investigated, such as their description and temporality. The transcribed content was thematically analyzed using an eclectic coding system, yielding five themes. The participants used different interchangeable descriptors (tired, sleepy, fatigued, exhausted) to express their daytime complaints. They enriched their description with indexes of magnitude (ranging from ‘not especially’ to ‘most gigantic, extreme’), oppositions to other states (using antipodes like energy, alertness, wakefulness, or rest), and indications of fluctuations over the day. Interestingly, the participants often used metaphors to express their experiences and their struggles. The lived experiences of the patients were found to not always align with common self-reported monitoring tools of sleepiness and to relate only in part with current conceptions. In practice, it is important to probe daytime complaints, such as daytime sleepiness, with a broader consideration, for example, by exploring antipodes, consequences, and time-of-day fluctuations.

Abstract Light exposure is an essential driver of health and well-being, and individual behaviours during rest and activity modulate physiologically relevant aspects of light exposure. Further understanding the behaviours that influence individual photic exposure patterns may provide insight into the volitional contributions to the physiological effects of light and guide behavioural points of intervention. Here, we present a novel, self-reported and psychometrically validated inventory to capture light exposure-related behaviour, the Light Exposure Behaviour Assessment (LEBA). An expert panel prepared the initial 48-item pool spanning different light exposure-related behaviours. Responses, consisting of rating the frequency of engaging in the per-item behaviour on a five-point Likert-type scale, were collected in an online survey yielding responses from a geographically unconstrained sample (690 completed responses, 74 countries, 28 time zones). The exploratory factor analysis (EFA) on an initial subsample (n = 428) rendered a five-factor solution with 25 items (wearing blue light filters, spending time outdoors, using a phone and smartwatch in bed, using light before bedtime, using light in the morning and during daytime). In a confirmatory factor analysis (CFA) performed on an independent subset of participants (n = 262), we removed two additional items to attain the best fit for the five-factor solution (CFI = 0.95, TLI = 0.95, RMSEA = 0.06). The internal consistency reliability coefficient for the total instrument yielded McDonald’s Omega = 0.68. Measurement model invariance analysis between native and non-native English speakers showed our model attained the highest level of invariance (residual invariance CFI = 0.95, TLI = 0.95, RMSEA = 0.05). Lastly, a short form of the LEBA (n = 18 items) was developed using Item Response Theory on the complete sample (n = 690). The psychometric properties of the LEBA indicate the usability for measuring light exposure-related behaviours. The instrument may offer a scalable solution to characterise behaviours that influence individual photic exposure patterns in remote samples. The LEBA inventory is available under the open-access CC-BY license. Instrument webpage: https://leba-instrument.org/ GitHub repository containing this manuscript: https://github.com/leba-instrument/leba-manuscript .