Comparison of outcome and characteristics between 6343 COVID-19 patients and 2256 other community-acquired viral pneumonia patients admitted to Dutch ICUs

Purpose: Describe the differences in characteristics and outcomes between COVID-19 and other viral pneumonia patients admitted to Dutch ICUs. Materials and methods: Data from the National-Intensive-Care-Evaluation-registry of COVID-19 patients admitted between February 15th and January 1th 2021 and other viral pneumonia patients admitted between January 1st 2017 and January 1st 2020 were used. Patients' characteristics, the unadjusted, and adjusted in-hospital mortality were compared. Results: 6343 COVID-19 and 2256 other viral pneumonia patients from 79 ICUs were included. The COVID-19 patients included more male (71.3 vs 49.8%), had a higher Body-Mass-Index (28.1 vs 25.5), less comorbidities (42.2 vs 72.7%), and a prolonged hospital length of stay (19 vs 9 days). The COVID-19 patients had a significantly higher crude in-hospital mortality rate (Odds ratio (OR) = 1.80), after adjustment for patient characteristics and ICU occupancy rate the OR was respectively 3.62 and 3.58. Conclusion: Higher mortality among COVID-19 patients could not be explained by patient characteristics and higher ICU occupancy rates, indicating that COVID-19 is more severe compared to other viral pneumonia. Our findings confirm earlier warnings of a high need of ICU capacity and high mortality rates among relatively healthy COVID-19 patients as this may lead to a higher mental workload for the staff. (c) 2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/)

Leek production in conventional and organic arable-vegetable rotations in the Netherlands

Leek production, one of the most important vegetables grown on the sandy soils in the South East of the Netherlands, is known to have a high rate of nitrogen leaching. Nitrogen leaching from leek cultivation depends not only on the cropping strategy but also on the whole farming system. The objective of this study was to evaluate nitrogen losses and crop yield of leek cultivation and the total farming system with different fertilization strategies. A farming systems experiment with two conventional and one organic farming system with arable and vegetable crops on sandy soils was evaluated. One conventional farming system (LOW) had a low organic matter input consisting of crop residues and green manure crops only. The other conventional farming system (STANDARD) had a regular organic matter input including cattle and pig slurry. The organic system had a high organic matter input because of the use of farm yard manure and cow slurry. Data of crop yield, nutrient balances and nitrate leaching for the period 2011-2016 are discussed. In the LOW system, crop production was on average 5% lower than in STANDARD. Nitrogen surplus was lower in LOW than in STANDARD. Phosphorus surplus was about equal between the systems and potassium surplus was higher in LOW than in STANDARD. Nitrate leaching was comparable in LOW and STANDARD, but both above the limit set in the EU nitrates directive of 50 mg L-1. Other indicators of nitrogen leaching as soil mineral nitrogen content and nitrogen surplus indicate that leaching risk in LOW is lower than in STANDARD. Leek yield in the organic system was low because of incidences of pests and diseases. However, in years with low disease pressure yields were only a few percent lower compared to the conventional yields. Nutrient surpluses of N, P and K were high in the organic system. Nitrogen leaching was below 50 mg L-1 in the organic system. A dilemma still exists between crop yield and nitrate leaching in the conventional systems: lower nitrate leaching is coupled with lower crop yields. The organic system gives relatively low yield however with good results regarding nitrate leaching

Leek production in conventional and organic arable-vegetable rotations in the Netherlands

Leek production, one of the most important vegetables grown on the sandy soils in the South East of the Netherlands, is known to have a high rate of nitrogen leaching. Nitrogen leaching from leek cultivation depends not only on the cropping strategy but also on the whole farming system. The objective of this study was to evaluate nitrogen losses and crop yield of leek cultivation and the total farming system with different fertilization strategies. A farming systems experiment with two conventional and one organic farming system with arable and vegetable crops on sandy soils was evaluated. One conventional farming system (LOW) had a low organic matter input consisting of crop residues and green manure crops only. The other conventional farming system (STANDARD) had a regular organic matter input including cattle and pig slurry. The organic system had a high organic matter input because of the use of farm yard manure and cow slurry. Data of crop yield, nutrient balances and nitrate leaching for the period 2011-2016 are discussed. In the LOW system, crop production was on average 5% lower than in STANDARD. Nitrogen surplus was lower in LOW than in STANDARD. Phosphorus surplus was about equal between the systems and potassium surplus was higher in LOW than in STANDARD. Nitrate leaching was comparable in LOW and STANDARD, but both above the limit set in the EU nitrates directive of 50 mg L-1. Other indicators of nitrogen leaching as soil mineral nitrogen content and nitrogen surplus indicate that leaching risk in LOW is lower than in STANDARD. Leek yield in the organic system was low because of incidences of pests and diseases. However, in years with low disease pressure yields were only a few percent lower compared to the conventional yields. Nutrient surpluses of N, P and K were high in the organic system. Nitrogen leaching was below 50 mg L-1 in the organic system. A dilemma still exists between crop yield and nitrate leaching in the conventional systems: lower nitrate leaching is coupled with lower crop yields. The organic system gives relatively low yield however with good results regarding nitrate leaching.</p

Calcium hydroxide treatment does not alter the susceptibility of Enterococcus faecalis biofilms to sodium hypochlorite

Objective: To investigate the influence of calcium hydroxide (Ca(OH)2) on susceptibility to disinfection with sodium hypochlorite (NaOCl) of biofilm bacteria. Methods: Monospecies biofilms of eight Enterococcus faecalis strains were subjected to a 2-h challenge with Ca(OH)2. After a recovery phase, the biofilms were treated with a concentration of NaOCl that was lower than the minimum inhibitory concentration. In a metabolic assay, the efficacy of NaOCl disinfection in Ca(OH)2-challenged biofilms and unchallenged biofilms was evaluated. The data were analyzed with Mann-Whitney U and Kruskall- Wallis tests. A P value of less than 0.05 was considered statistically significant. Results: There were marginal differences in susceptibility to NaOCl among the E. faecalis strains. After the Ca(OH)2 challenge, seven strains remained equally susceptible to NaOCl disinfection whereas one strain be- came more resistant to NaOCl (P= 0.03). Conclusion: After a Ca(OH)2 challenge, in general E. faecalis remained equally susceptible to disinfection with NaOCl

Cytotoxicity, interaction with dentine and efficacy on multispecies biofilms of a modified salt solution intended for endodontic disinfection in a new in vitro biofilm model

Aim To investigate the cytotoxicity of a modified salt solution (MSS) and evaluate the antimicrobial properties of MSS on in vitro biofilm models. Methodology In a metabolic assay, fibroblasts derived from periodontal ligaments (PDL) of human extracted teeth were cultured and challenged with MSS or controls. Then, in active attachment biofilm models, the efficacy of MSS in the presence of dentine powder and in eliminating mature biofilms was investigated. In the dentine assay, a biofilm of Enterococcus faecalis was employed. For the final assay, microorganisms were retrieved from infected root canals and cultured to produce biofilms. After the treatments with MSS or the controls, the biofilms were collected, serially diluted and plated. The colony-forming units were counted. One-way anova was used to analyse the differences between the groups. A P 0.05). In endodontic biofilms, the culturable bacteria were equally reduced by MSS, 2% chlorhexidine (CHX) or 2% sodium hypochlorite (NaOCl) (P > 0.05). Conclusions Modified salt solution is noncytotoxic in vitro and has good antimicrobial properties equal to CHX and NaOCl. Although the results are promising, ex vivo and in vivo studies are needed before its use as an interappointment root canal dressing can be considered

Additional disinfection with a modified salt solution in a root canal model

Objectives The aim of this study is to investigate the disinfecting properties of a modified salt solution (MSS) and calcium hydroxide (Ca(OH)2) in a non-direct-contact ex-vivo model. Methods Seventy-four single-canal roots infected with Enterococcus faecalis were treated with 1% sodium hypochlorite (NaOCl) irrigation or with NaOCl irrigation with subsequent dressing with MSS or Ca(OH)2. After removal of the dressings, the roots were filled with bacterial growth medium and incubated for seven days to enable the surviving bacteria to repopulate the root canal lumen. Growth was determined by sampling the root canals with paper points before treatment (S1), after treatment (S2) and incubation after treatment (S3). The colony forming units were counted at S1 and S2. At S3, growth was determined as no/yes regrowth. The Kruskal-Wallis, McNemar and χ2 test were used for statistical analyses. Results At S2, in the NaOCl group, growth was found in 5 of 19 root canals. After the removal of MSS or Ca(OH)2 bacteria were retrieved from one root canal in both groups. At S3, repopulation of the root canals had occurred in 14 of 19 roots after sole NaOCl irrigation, 6 of 20 roots after MSS-dressing and in 14 of 20 roots after Ca(OH)2-dressing. MSS was more effective in preventing regrowth than Ca(OH)2 (P = 0.009). Conclusions The modified salt solution prevented regrowth in roots which indicates that it can eliminate persistent bacteria. Dressing the root canals with Ca(OH)2 did not provide additional disinfection after NaOCl irrigation

Effect van organische stofbeheer op opbrengst, bodemkwaliteit en stikstofverliezen op een zuidelijke zandgrond

In het bedrijfssysteemonderzoek Bodemkwaliteit op zand op WUR-proeflocatie Vredepeel worden twee gangbare bedrijfssystemen met elkaar vergeleken gedurende de periode 2011-2016: één systeem met een gebruikelijke organische stofaanvoer met gebruik van drijfmest (STANDAARD) en één systeem met een lage organische stofaanvoer met gebruik van meststoffen zonder of met een laag gehalte organische stof (LAAG). Systeem LAAG heeft een 5% lagere totale droge stofproductie (p<0,05) en een lager risico op stikstofuitspoeling. De nitraatconcentraties in het grondwater (n.s.), de N-min voorraden in de bodem in het najaar (p<0,1), en het stikstofoverschot (n.s.) zijn in LAAG in alle gevallen lager dan STANDAARD. In beide systemen ligt de nitraatconcentratie in het grondwater boven de norm in de Europese nitraatrichtlijn (50 mg/l). Het organisch stofgehalte in LAAG is 0,4%-punt lager dan STANDAARD (p<0,01). Andere bodemparameters zijn in de loop van de tijd van de proef niet veranderd. Er kon geen duidelijk verband afgeleid worden tussen de aanvoer van organische stof en lachgasemissies. Aanvoer van extra organische stof in de vorm van compost in zowel LAAG als STANDAARD leidt tot hogere opbrengsten (n.s.), met name in systeem LAAG, maar geen verhoging van de uitspoeling. De opbrengsten in STANDAARD liggen gemiddeld 15% lager dan de praktijkopbrengsten op de proeflocatie, mogelijk veroorzaakt door de strikte bemestingsstrategie sinds de start van het bedrijfssystemenonderzoek in 1988. Met de indicaties voor lagere stikstofverliezen, hoewel nog steeds boven de nitraatnorm, bij een lagere aanvoer van organische stof, maar tegelijkertijd lagere opbrengsten geeft dit onderzoek een dilemma weer tussen een belangrijk milieuaspect en de economie van het boerenbedrijf

Lezen op school of thuis

In deze dataset en het bijbehorende rapport worden de resultaten van het biologische bedrijfssysteem op WUR-proeflocatie Vredepeel in de periode 2001-2016 gepresenteerd met focus op gewasopbrengst, bodemkwaliteit, bemesting en stikstofuitspoeling. Het biologisch systeem heeft opbrengsten die gemiddeld 6% onder het streven liggen, een goede bodemvruchtbaarheid en een nitraatconcentratie in het grondwater onder de norm van de nitraatrichtlijn. De nutriëntenoverschotten van stikstof, fosfaat en kali zijn hoger dan de streefwaarde. De opbrengsten liggen gemiddeld ruim onder die van de gangbare teelt door het optreden van ziekten en plagen. Veranderingen in opbrengst, bodemkwaliteit en uitspoeling in de periode 2000-2016 zijn niet met metingen vastgesteld behalve een stijging in organisch stofgehalte. Hierdoor kan ook niet aangetoond worden dat door biologische landbouw de bodemkwaliteit verbetert en ecosysteemdiensten verbeteren. Onduidelijk is hoe het biologisch systeem tot een lage uitspoeling komt bij een relatief hoge stikstof- en organische stofaanvoer. Nader onderzoek is hiervoor nodig