Effect of air distribution and spray liquid distribution of a cross-flow fan orchard sprayer on spray deposition in fruit trees

In a 4-year ongoing research programme in the Netherlands, we focus to maximise spray deposition in pome fruit trees and minimise spray deposition underneath the trees on the ground and minimise spray drift. For a cross-flow fan orchard sprayer we therefore measured spray deposition in the tree as an effect of different air settings and nozzle types. Nozzle types chosen were the Albuz ATR lilac (as a reference) and the Albuz TVI8001, both sprayed at 7 bar spray pressure. The orchard sprayer was a Munckhof cross-flow fan sprayer with a 2.75 m high cross-flow construction on top of the axial fan, equipped with 8 nozzles on both sides. At a forward speed of 6.5 km/h the spray volume was 200 L/ha and 290 L/ha, for respectively the Albuz lilac and Albuz TVI8001 nozzles. Air settings were: High air setting - 540 rpm PTO; and Low air setting - 540 rpm, 400 rpm, and 300 rpm PTO. Liquid distributions were measured with an AAMS-Salvarani Vertical patternator with discs, and air distribution was measured with a self-constructed measuring device equipped with ultrasonic anemometers and a handheld vane-anemometer. Liquid distribution in the apple trees (cv. Elstar) was measured in the full leaf growing stage (following ISO 22522). First results show a good correlation between air distribution and liquid distribution. Vertical liquid distribution measured on the liquid measuring device correlates also very good with the liquid distribution at different heights in the tree. However, air distribution and especially air speed of the orchard sprayer showed that decreasing air assistance increased the spray deposition in the fruit trees. Showing that air assistance is an important parameter to be taken up in the advice to fruit growers.In a 4-year ongoing research programme in the Netherlands, we focus to maximise spray deposition in pome fruit trees and minimise spray deposition underneath the trees on the ground and minimise spray drift. For a cross-flow fan orchard sprayer we therefore measured spray deposition in the tree as an effect of different air settings and nozzle types. Nozzle types chosen were the Albuz ATR lilac (as a reference) and the Albuz TVI8001, both sprayed at 7 bar spray pressure. The orchard sprayer was a Munckhof cross-flow fan sprayer with a 2.75 m high cross-flow construction on top of the axial fan, equipped with 8 nozzles on both sides. At a forward speed of 6.5 km/h the spray volume was 200 L/ha and 290 L/ha, for respectively the Albuz lilac and Albuz TVI8001 nozzles. Air settings were: High air setting - 540 rpm PTO; and Low air setting - 540 rpm, 400 rpm, and 300 rpm PTO. Liquid distributions were measured with an AAMS-Salvarani Vertical patternator with discs, and air distribution was measured with a self-constructed measuring device equipped with ultrasonic anemometers and a handheld vane-anemometer. Liquid distribution in the apple trees (cv. Elstar) was measured in the full leaf growing stage (following ISO 22522). First results show a good correlation between air distribution and liquid distribution. Vertical liquid distribution measured on the liquid measuring device correlates also very good with the liquid distribution at different heights in the tree. However, air distribution and especially air speed of the orchard sprayer showed that decreasing air assistance increased the spray deposition in the fruit trees. Showing that air assistance is an important parameter to be taken up in the advice to fruit growers

The AGE reader:a non-invasive method to assess long term tissue damage

AIMS: Advanced glycation endproducts (AGEs) are sugar modified adducts which arise during non-enzymatic glycoxidative stress. These compounds may become systemically elevated in disease states, and accumulate in tissue, especially on long-lived proteins. AGEs have been implicated in various acute, and chronic diseases, stressing the need for reliable and comprehensive measuring techniques. Measurement of AGEs in tissue such as skin requires skin biopsies, which is an invasive procedure. The AGE Reader has been developed to assess skin autofluorescence (SAF) non-invasively by the fluorescent properties of several AGEs. RESULTS/CONCLUSION: Various studies have shown that SAF is a useful marker of disease processes associated with oxidative stress. It is prospectively associated with development of cardiovascular events in patients with diabetes, renal or cardiovascular disease, and it predicts diabetes, cardiovascular disease and mortality in the general population. However, when measuring SAF in individual subjects, several factors may limit the reliability of the measurement, and hamper its use as a systemic biomarker for AGEs. These include endogenous factors present in the skin that absorb emission light such as melanin in dark-skinned subjects, but also factors that lead to temporal changes in SAF such as acute diseases and strenuous physical exercise associated with glycoxidative stress. Also, exogenous factors could potentially influence SAF levels inadvertently such as nutrition, and for example the application of skin care products. This review will give an overview of the AGE Reader functionality and the intrinsic, and exogenous factors which potentially influence the SAF assessment in individual subjects

A versatile, compartmentalised gut-on-a-chip system for pharmacological and toxicological analyses

A novel, integrated, in vitro gastrointestinal (GI) system is presented to study oral bioavailability parameters of small molecules. Three compartments were combined into one hyphenated, flow-through set-up. In the first compartment, a compound was exposed dynamically to enzymatic digestion in three consecutive microreactors, mimicking the processes of the mouth, stomach, and intestine. The resulting solution (chyme) continued to the second compartment, a flow-through barrier model of the intestinal epithelium allowing absorption of the compound and metabolites thereof. The composition of the effluents from the barrier model were analysed either offline by electrospray-ionisation-mass spectrometry (ESI-MS), or online in the final compartment using chip-based ESI-MS. Two model drugs, omeprazole and verapamil, were used to test the integrated model. Omeprazole was shown to be broken down upon treatment with gastric acid, but reached the cell barrier unharmed when introduced to the system in a manner emulating an enteric-coated formulation. In contrast, verapamil was unaffected by digestion. Finally, a reduced uptake of verapamil was observed when verapamil was introduced to the system dissolved in apple juice, a simple food matrix. It is envisaged that this integrated, compartmentalised GI system has potential for enabling future research in the fields of pharmacology, toxicology, and nutrition

Biomassa-afhankelijk doseren van gewasbeschermingsmiddelen

Recentelijk zijn enkele doorbraken gerealiseerd op het gebied van biomassa-afhankelijk doseren in open teelten. Het gaat hierbij om plaatsspecifieke dosering van bepaalde herbiciden en fungiciden op basis van de hoeveelheid bovengrondse biomassa onder de spuitdoppen. Om dit effectief te maken, zijn toegesneden sensoren, beslisregels en spuitapparatuur nodig. Plaatsspecifieke dosering van loofdodingsmiddelen in consumptieaardappelen is nu praktijkrijp middels MLHD-PHK (Minimum Lethal Herbicide Dose-Potato Haulm Killing) in combinatie met de N-sensor (stikstof-sensor), of SensiSpray. In de testfase werd een reductie van gemiddeld 50% in het gebruik van loofdodingsmiddel t.o.v. gangbare praktijk bereikt. In dit artikel wordt een overzicht gegeven van onderwerpen op het gebied van biomassa-afhankelijk doseren van gewasbeschermingsmiddelen waarbij de Plant Science Groep (PSG) van Wageningen UR trekker van de ontwikkeling is

Study protocol of IMAGINE-HD: imaging iron accumulation and neuroinflammation with 7T-MRI + CSF in Huntington's disease

IntroductionStrong evidence suggests a significant role for iron accumulation in the brain in addition to the well-documented neurodegenerative aspects of Huntington’s disease (HD). The putative mechanisms by which iron is linked to the HD pathogenesis are multiple, including oxidative stress, ferroptosis and neuroinflammation. However, no previous study in a neurodegenerative disease has linked the observed increase of brain iron accumulation as measured by MRI with well-established cerebrospinal fluid (CSF) and blood biomarkers for iron accumulation, or with associated processes such as neuroinflammation. This study is designed to link quantitative data from iron levels and neuroinflammation metabolites obtained from 7T MRI of HD patients, with specific and well-known clinical biofluid markers for iron accumulation, neurodegeneration and neuroinflammation. Biofluid markers will provide quantitative measures of overall iron accumulation, neurodegeneration and neuroinflammation, while MRI measurements on the other hand will provide quantitative spatial information on brain pathology, neuroinflammation and brain iron accumulation, which will be linked to clinical outcome measures.MethodsThis is an observational cross-sectional study, IMAGINE-HD, in HD gene expansion carriers and healthy controls. We include premanifest HD gene expansion carriers and patients with manifest HD in an early or moderate stage. The study includes a 7T MRI scan of the brain, clinical evaluation, motor, functional, and neuropsychological assessments, and sampling of CSF and blood for the detection of iron, neurodegenerative and inflammatory markers. Quantitative Susceptibility Maps will be reconstructed using T2* weighted images to quantify brain iron levels and Magnetic Resonance Spectroscopy will be used to obtain information about neuroinflammation by measuring cell-specific intracellular metabolites’ level and diffusion. Age and sex matched healthy subjects are included as a control group.DiscussionResults from this study will provide an important basis for the evaluation of brain iron levels and neuroinflammation metabolites as an imaging biomarker for disease stage in HD and their relationship with the salient pathomechanisms of the disease on the one hand, and with clinical outcome on the other.Radiolog

Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy:One-year follow-up

Objective: Follow-up of patients with treatment-resistant Raynaud's phenomenon (RP) one-year after single-port thoracoscopic sympathicotomy (SPTS). Methods: Eight patients (six males, two females, median age of 45 years) with treatment-resistant RP underwent left-sided SPTS at the third rib (R3), unilaterally. Questionnaires were taken, and number and duration of RP attacks were reported over a 2-week period. Perfusion was assessed with a cooling and recovery procedure at baseline and one year after SPTS. Furthermore, laser speckle contrast analysis, pulse wave velocity, heart rate variability and nailfold capillary microscopy were performed. Results: One year after SPTS the duration of the attacks of was reduced with 1.9 h in the left hand versus 0.3 h in the right hand. Furthermore, three aspects of the questionnaire showed a significant improvement (role limitations due to physical health (p = 0.017), pain (p = 0.027) and physical functioning (p = 0.025)). The total area under the curve of the total cooling and recovery procedure of the left hand was larger one year after surgery (101 (75–140) at baseline versus 118 (95–190) one year post-operatively, p = 0.012), implying a better perfusion in the fingers. This was mainly due to the improvement during the recovery phase (21 (1–41) at baseline versus 38 (24–43) one year post-operatively, p = 0.028). Conclusion: One year after unilateral R3 SPTS the benefit with regard to the majority of outcome variables persisted, though some effects seem to attenuate. Long-term effects and long-term follow-up results will be investigated in an on-going study. Clinical trial registration number: NCT02680509

Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy:a novel minimally invasive endoscopic technique

OBJECTIVE: To assess the minimally invasive single-port thoracoscopic sympathicotomy feasibility and efficacy in patients with treatment-resistant RP. METHODS: Single-port thoracoscopic sympathicotomy was performed unilaterally on the left side in eight patients with RP (six males, two females, with a median age of 45.2 years). Five patients had primary and three had secondary RP. Perfusion effects in the hands were assessed at baseline and after 1 month by using a cooling and recovery procedure, and by using laser speckle contrast analysis. Number and duration of RP attacks were reported over a 2-week period. RESULTS: Patient satisfaction was 100% after surgery. After surgery, a unilateral improvement in perfusion was observed in the left hand compared with the right hand, with cooling and recovery (P = 0.008) and with laser speckle contrast analysis (P = 0.023). In addition, the number and duration of the attacks in the left hand decreased compared with the right hand (both P = 0.028). No serious adverse events occurred in a follow-up period of at least 10 months. CONCLUSION: Single-port thoracoscopic sympathicotomy is feasible and can be effective in improving hand perfusion in patients with RP. However, long-term efficacy needs to be established. CLINICAL TRIAL REGISTRATION NUMBER: NCT02680509

Perceived Barriers to and Facilitators of Physical Activity in Recipients of Solid Organ Transplantation, a Qualitative Study

Background Sufficient physical activity is important for solid organ transplant recipients (heart, lung, liver, kidney). However, recipients do not meet the recommended amount or required type of physical activity. The perceived barriers to and facilitators of physical activity in this population are largely unknown. Methods Semi-structured in depth interviews were conducted with solid organ transplant recipients in order to explore experienced barriers and facilitators. Qualitative methodology with thematic line-by-line analysis was used for analysis, and derived themes were classified into personal and environmental factors. Results The most important indicated barriers were physical limitations, insufficient energy level, fear, and comorbidities. The most frequently mentioned facilitators included motivation, coping, consequences of (in) activity, routine/habit, goals/goal priority, and responsibility for the transplanted organ. Neutral factors acting as a barrier or facilitator were self-efficacy and expertise of personnel. A comparison of barriers and facilitators between transplant recipient groups yielded no overt differences. Conclusion Several personal and environmental factors were indicated that should be considered in intervention development to increase physical activity behavior in solid organ transplant recipients

Pesticide Exposure of Residents Living Close to Agricultural Fields in the Netherlands:Protocol for an Observational Study

Background: Application of pesticides in the vicinity of homes has caused concern regarding possible health effects in residents living nearby. However, the high spatiotemporal variation of pesticide levels and lack of knowledge regarding the contribution of exposure routes greatly complicates exposure assessment approaches. Objective: The objective of this paper was to describe the study protocol of a large exposure survey in the Netherlands assessing pesticide exposure of residents living close ( Methods: We performed an observational study involving residents living in the vicinity of agricultural fields and residents living more than 500 m away from any agricultural fields (control subjects). Residential exposures were measured both during a pesticide use period after a specific application and during the nonuse period for 7 and 2 days, respectively. We collected environmental samples (outdoor and indoor air, dust, and garden and field soils) and personal samples (urine and hand wipes). We also collected data on spraying applications as well as on home characteristics, participants' demographics, and food habits via questionnaires and diaries. Environmental samples were analyzed for 46 prioritized pesticides. Urine samples were analyzed for biomarkers of a subset of 5 pesticides. Alongside the field study, and by taking spray events and environmental data into account, we developed a modeling framework to estimate environmental exposure of residents to pesticides. Results: Our study was conducted between 2016 and 2019. We assessed 96 homes and 192 participants, including 7 growers and 28 control subjects. We followed 14 pesticide applications, applying 20 active ingredients. We collected 4416 samples: 1018 air, 445 dust (224 vacuumed floor, 221 doormat), 265 soil (238 garden, 27 fields), 2485 urine, 112 hand wipes, and 91 tank mixtures. Conclusions: To our knowledge, this is the first study on residents' exposure to pesticides addressing all major nondietary exposure sources and routes (air, soil, dust). Our protocol provides insights on used sampling techniques, the wealth of data collected, developed methods, modeling framework, and lessons learned. Resources and data are open for future collaborations on this important topic

Quaking promotes monocyte differentiation into pro-atherogenic macrophages by controlling pre-mRNA splicing and gene expression

A hallmark of inflammatory diseases is the excessive recruitment and influx of monocytes to sites of tissue damage and their ensuing differentiation into macrophages. Numerous stimuli are known to induce transcriptional changes associated with macrophage phenotype, but posttranscriptional control of human macrophage differentiation is less well understood. Here we show that expression levels of the RNA-binding protein Quaking (QKI) are low in monocytes and early human atherosclerotic lesions, but are abundant in macrophages of advanced plaques. Depletion of QKI protein impairs monocyte adhesion, migration, differentiation into macrophages and foam cell formation in vitro and in vivo. RNA-seq and microarray analysis of human monocyte and macrophage transcriptomes, including those of a unique QKI haploinsufficient patient, reveal striking changes in QKI-dependent messenger RNA levels and splicing of RNA transcripts. The biological importance of these transcripts and requirement for QKI during differentiation illustrates a central role for QKI in posttranscriptionally guiding macrophage identity and function.No sponso