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Physically consistent coupling conditions at the fluid–porous interface with correctly determined effective parameters are necessary for accurate modeling and simulation of various applications. To describe single-fluid-phase flows in coupled free-flow and porous-medium systems, the Stokes/Darcy equations are typically used together with the conservation of mass across the interface, the balance of normal forces and the Beavers–Joseph condition on the tangential velocity. The latter condition is suitable for flows parallel to the interface but not applicable for arbitrary flow directions. Moreover, the value of the Beavers–Joseph slip coefficient is uncertain. In the literature, it is routinely set equal to one that is not correct for many applications, even if the flow is parallel to the porous layer. In this paper, we reformulate the generalized interface condition on the tangential velocity component, recently developed for arbitrary flows in Stokes/Darcy systems, such that it has the same analytical form as the Beavers–Joseph condition. We compute the effective coefficients appearing in this modified condition using theory of homogenization with boundary layers. We demonstrate that the modified Beavers–Joseph condition is applicable for arbitrary flow directions to the fluid–porous interface. In addition, we propose an efficient two-level numerical algorithm based on simulated annealing to compute the optimal Beavers–Joseph parameter.Article Highlights A modification of the Beavers–Joseph condition is proposed based on recently developed generalized coupling conditions. The Beavers-Joseph parameter can be found only for unidirectional flows. An efficient numerical algorithm to determine the optimal Beavers-Joseph parameter is developed.

Horticultural production systems have to move forwards to an environment-friendly and sustainable plant production. Basic substances can be added to reduce the use of synthetic plant protectant in conventional plant protection strategies. Regarding the protection of ornamental plants, less is known about the usage and behaviour of these alternative strategies and components. In our study, an infection of Podosphaera pannosa and Erysiphe polygoni in two different cultivars of cutting roses and one cultivar of French hydrangea was investigated. We studied the effect of a weekly foliar treatment of the basic substance chitosan (0.05 g/m2) compared to a water control and potassium hydrogen carbonate (VitiSan, Biofa GmbH, Münsing, Germany) in both production systems. As a result, in cutting roses as well as in French hydrangea, we found a significantly decreased infected leaf area following the use of chitosan and VitiSan compared to the water control. In both treatments, we found a stronger effect in French hydrangea, compared to roses. Results also indicate that the basic substance chitosan has to be used at a low pathogen level. We present a promising approach to reduce conventional plant protectants in ornamental plant production.

Accelerated lakes eutrophication is one of the greatest challenges nowadays. To counteract its negative effects, large-scale restoration treatments are carried out worldwide. However, research in this field is mainly focused on the process effectiveness and there is a scarcity of studies concerning the impact of restoration treatments on water organisms and ecosystem homeostatsis. Our microcosm study presents the effects of a phosphorus coagulant (iron [III] chloride) on functional traits changes, oxidative stress and macro- and microelement stoichiometry disturbances in macrophyte Myriophyllum spicatum, a model species inhabiting eutrophic waters. Application of the coagulant to experimental vessels influenced the physicochemical and optical parameters of water and led to significant changes in biogeochemistry. Stoichiometric alterations were reflected by disturbances in the relative contents of macro- (C, N, P, Ca, Mg) and microelements (Fe, Zn, Cu, Co) and induced luxury consumption of available ions. Physicochemical and stoichiometric changes mutually exerted negative influence on M. spicatum functional traits. The parameters of oxidative stress remained at low levels, comparable to the untreated control whereas stoichiometric analysis revealed the activation of mechanisms responsible for minimizing low light stress. The ability of M. spicatum to maintain homeostasis of Cu and Co under simulated chemical water restoration was closely related to high concentrations of Fe and Zn ions, which simultaneously were not subjected to homeostasis control. Thus, chemical lake restoration treatments based on phosphorus coagulants are not as environmentally safe as previously considered and may have far-reaching consequences for the biogeochemical cycle and food web functioning.

To promote judicious prescribing of methicillin-resistant Staphylococcus aureus (MRSA)-active therapy for skin and soft tissue infections (SSTI), we previously developed an MRSA risk assessment tool. The objective of this study was to validate this risk assessment tool internationally.A multicenter, prospective cohort study of adults with purulent SSTI was performed at seven international sites from July 2016 to March 2018. Patient MRSA risk scores were computed as follows: MRSA infection/colonization history (2 points); previous hospitalization, previous antibiotics, chronic kidney disease, intravenous drug use, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), diabetes with obesity (1 point each). Predictive performance of MRSA surveillance percentage, MRSA risk score, and estimated MRSA probability (surveillance percentage adjusted by risk score) were quantified using the area under the receiver operating characteristic curves (aROC) and compared. Performance characteristics of different risk score thresholds across varying baseline MRSA prevalence were examined.Two hundred three patients were included. Common SSTI were wounds (28.6%), abscess (25.1%), and cellulitis with abscess (20.7%). Patients with higher risk scores were more likely to have MRSA (P 0.001). The MRSA risk score aROC (95%CI) [0.748 (0.678-0.819)] was significantly greater than MRSA surveillance percentage [0.646 (0.569-0.722)] (P = 0.016). Estimated MRSA probability aROC [0.781 (0.716-0.845)] was significantly greater than surveillance percentage (P 0.001) but not the risk score (P = 0.192). The estimated negative predictive value (NPV) of an MRSA score ≥ 1 (i.e., a score of 0) was greater than 90% when MRSA prevalence was 30% or less.The MRSA risk score and estimated MRSA probability were significantly more predictive of MRSA compared with surveillance percentage. An MRSA risk score of zero had high predictive value and could help avoid unnecessary empiric MRSA coverage in low-acuity patients. Further study, including impact of such risk assessment tools on prescribing patterns and outcomes are required before implementation.

Infections caused by multidrug-resistant (MDR), extensively drug-resistant (XDR), and difficult-to-treat (DTR) Pseudomonas aeruginosa are increasingly challenging to combat. Ceftolozane-tazobactam (C/T) is a novel β-lactam-β-lactamase inhibitor combination now commonly used to treat MDR and XDR P. aeruginosa. Lower respiratory tract infections (LRTIs) remain the most common source of infection caused by MDR/XDR P. aeruginosa. Comparative effectiveness studies to date have been limited by the type of comparator agents (i.e., aminoglycosides and polymyxins) and the inclusion of multiple infection sources (i.e., urinary tract, abdominal, skin and soft tissue, etc.).We performed a multicenter, retrospective analysis of adults with LRTI caused by MDR or XDR P. aeruginosa admitted from January 2014 to December 2019. We aimed to compare clinical outcomes between patients who received C/T (n = 118) versus best alternative therapy (n = 88). The primary outcome was clinical failure, defined as 30-day mortality and/or an adverse drug reaction on antibiotic therapy.Two hundred and six patients met inclusion criteria. The C/T group had a significantly higher proportion of XDR P. aeruginosa and ventilator-associated bacterial pneumonia (VABP). After multivariable logistic regression, C/T treatment was independently associated with a 73.3% reduction in clinical failure compared to those who received best alternative therapy (P 0.001). The number needed to harm with best alternative therapy was 3.Our results suggest that C/T is a safe and effective therapeutic regimen for patients with MDR and XDR P. aeruginosa LRTI.

Alternative strategies in plant protection are required due to political and environmental conditions. Basic substances can potentially benefit for modern plant protection in conventional and organic horticulture. In the case of plant protection in ornamentals, little is known about the effect of basic substances within the canopy to reduce foliar diseases. Podosphaera pannosa is one of the most severe diseases in the production of cut roses. In this study, different cultivars of cut roses were sprayed weekly with an extract of Equisetum arvense (4 g dried plant material/L), an aqueous solution of hydrogen peroxide (10 g/L) and a commercial plant protection product containing potassium hydrogen carbonate (VitiSan, Biofa GmbH, Münsingen, Germany) during two experimental trials. As a result, the symptoms of infected leaf area could be reduced significantly as the experiments progressed. Furthermore, no negative effects such as a reduction of plant growth or the number of marketable flowers were observed. The results indicate that the foliar application of the basic substances hydrogen peroxide and E. arvense-extract has the potential to reduce the use of synthetic plant protection products in conventional and organic horticulture.

The technique of embedding components inside printed circuit boards (PCBs) is described, using different filling masses. To investigate the possibility of placing the components inside the printed circuit board, a residual circuit breaker with an overload protection (RCBO) system was adapted. Four types of fillings (two epoxy and two silicone) were used in the tests, which were carried out showing the full functionality of the systems embedded in the PCB, regardless of the applied sealing compound. A certain disadvantage was the shrinkage of the applied masses, which was visible in some cases in the occurrence of gaps in the flooding spaces. However, it should be emphasized that the tests were preliminary and that the adjustment of the filling shrinkage will be optimized in subsequent tests.

Inappropriate antibiotic use in COVID-19 is often due to treatment of presumed bacterial coinfection. Predictive factors to distinguish COVID-19 from COVID-19 with bacterial coinfection or bloodstream infection are limited.We conducted a retrospective cohort study of 595 COVID-19 patients admitted between March 8, 2020, and April 4, 2020, to describe factors associated with a bacterial bloodstream coinfection (BSI). The primary outcome was any characteristic associated with BSI in COVID-19, with secondary outcomes including 30-day mortality and days of antibiotic therapy (DOT) by antibiotic consumption (DOT/1000 patient-days). Variables of interest were compared between true BSI (n = 25) and all other COVID-19 cases (n = 570). A secondary comparison was performed between positive blood cultures with true BSI (n = 25) and contaminants (n = 33) on antibiotic use.Fever ( 38 °C) (as a COVID-19 symptom) was not different between true BSI (n = 25) and all other COVID-19 patients (n = 570) (p = 0.93), although it was different as a reason for emergency department (ED) admission (p = 0.01). Neurological symptoms (ED reason or COVID-19 symptom) were significantly higher in the true BSI group (p 0.01, p 0.01) and were independently associated with true BSI (ED reason: OR = 3.27, p 0.01; COVID-19 symptom: OR = 2.69, p = 0.03) on multivariate logistic regression. High (15-19.9 × 10True BSI in COVID-19 was associated with neurological symptoms and nonsignificant higher WBC, and led to overall higher 30-day mortality and worse patient outcomes.

To fill the knowledge gap about the functioning of the lake–river system subjected to restoration treatments, two tributaries, a shallow, restored lake and its outflow, were examined. The quality of water inflows, lake and outflow was compared before (BR), during sustainable (SR, deep water aeration, phosphorus inactivation and biomanipulation for 3 years) and limited lake restoration (LR, only aeration for 2 years). Physico-chemical parameters were analysed monthly at five stations. The nutrient concentrations at the inflows decreased over the years due to the improvement of water and sewage management in the catchment (in Mielcuch from 18.0 to 8.0 mgN L−1 and 1.0 to 0.6 mgP L−1). The decline at the outflow was the result of a better quality of water at the tributaries and SR in the lake. During LR, decrease of phosphorus concentration still occurred (0.11 mgP L−1), but nitrogen concentration slightly increased (3.9 mgN L−1). Although the outflowing waters still transported a high content of chlorophyll a and suspended solids during SR, their amount was lower (34.5 μg L−1 and 17 mg L−1, respectively) than that during BR and LR. During restoration, it is significant to monitor the water quality not only in the lake but also at the outflow. The slow deterioration of water quality at the outflow indicated that introducing changes in the applied restoration methods must be done carefully because the previously achieved effect may be lost. Hence, restoration of the upstream lake and good quality of its tributaries are of great importance for water bodies located downstream.

We study the effects of extrusion treatment with subsequent rolling in combination with annealing, changes in the direction of rolling after each pass (original sheet), and alternating bending (AB) for 0.5; 1; 3, and 5 cycles, as well as the effect of texture on the parameter of damage D and the elastic and mechanical properties of the material in uniaxial tensile tests (ultimate strength σu, yield point σ0.2, and relative elongation Δl/l) for the ZE10 magnesium alloy with zinc, zirconium, and rare-earth metals. We determined the values of damage parameters according to the changes in the modulus of elasticity after the corresponding number of AB cycles relative to its values in different directions for the original analyzed sheet. Note that the damage parameters were computed by using the models of equivalent strains and equivalent elastic energy. It is established that the elasticity moduli, ultimate strengths, conventional yield points, and relative elongations averaged over all directions in the sheets of the alloy, decrease and, on the contrary, the corresponding values of damage parameters increase with the number of AB cycles and obey parabolic laws, as follows from the correlation and regression analyses. The anisotropy of indicated characteristics also weakens under the conditions of alternating bending. It was also shown that there exist strong correlation relations between the Kearns texture parameters, on the one hand, and the moduli of elasticity, damage parameters, ultimate strengths, yield points, and relative elongation, on the other hand. We deduce the corresponding quadratic regression equations with high values of the reliability index of approximation. It was also shown that the indicated changes in the analyzed properties are mainly caused by the variations of crystallographic textures.

In this study, wood plastic composites (WPC) made of poly(lactic acid) PLA and a bark-filler were manufactured. Two degrees of bark comminution (10–35 mesh and over 35 mesh) and varied content of bark (40, 50 and 60%) were investigated. The studied panels were compared with analogically manufactured HDPE boards. The manufacture of composites involved two stages: at first, WPC granules with the appropriate formulation were produced using the extruder (temperatures in individual extruder sections were 170–180 °C) and crushing using a hammer mill after cooling the extruded composite; secondly, the obtained granulate was used to produce boards with nominal dimensions of 300 × 300 × 2.5 mm3 by flat pressing in a mold, using a single daylight press at a temperature 200 °C. The study proved that comminuted bark can be applied as a filler in PLA composites. However, an increase in bark content decreased mechanical properties (MOR, MOE) and deteriorated humidity resistance (high TS and WA) of the panels. Along with the increase in bark content, an increase in the contact angle of the composite surfaces and a decrease in the total surface energy were noted. It was also found that PLA composites have higher strength parameters and lower moisture resistance compared to HDPE composites with the same bark content.Graphical abstract