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This study examines the seasonal forecast of the North American Multi-Model Ensemble (NMME) over Central Africa (CA), which encompasses a region of the world where the economies of the countries are heavily dependent on agriculture and livestock. The forecast evaluation is done over the 4 seasons: December to February (DJF), March to May (MAM), June to August (JJA), September to November (SON) between 0 to 5 months lead time before the beginning of each season corresponding to many regional climate perspectives. Deterministic and categorical approaches focusing on the rainfall variable were used to assess NMME models over CA. The observed and predicted rainfall have been divided into three categories: below normal, normal and above normal. The results show that for 0 to 2 months lead time, the NMME Multi-model Ensemble Mean (MME) reproduces rainfall peaks (9 to 10 mm / days) at the level of Atlantic coast and in East of Democratic Republic of Congo in MAM and SON. Always between 0 to 2 months lead time, values of correlation coefficients (R) of all seasons are greater than 0.72. For 3 to 5 months lead time, low values of R are observed. It follows that probabilities of detection (POD) are greater than 50\% for all different normal seasons and less than 45\% for below and above normal seasons. On the other hand, high false alarm (FAR) values and low Critical Success Index (CSI) values are observed for both below and above normal seasons. The NMME model emerges as an interesting tool capable of providing important seasonal characteristics up to several months (5 months) before the start of the season in the CA, which will allow proper consideration of meteorological phenomena.

Background There is a high prevalence of psychoactive substance use among patients with mental health disorders. The optimal treatment of patients with mental health disorders requires an awareness of their history pertaining substance use. Several methods are used to assess the use of substance. Each of them embodies its limitations. This study aimed at assessing the diagnostic capability of a self-report psychoactive substance use among patients at the National Psychiatric University Hospital of Cotonou, Benin. Methods A cross-sectional survey was conducted from August 1, 2021 to November 24, 2021. A total of 157 consenting patients admitted to psychiatric consultations were successively enrolled in the ongoing study. They were screened for the use of psychoactive substance with Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), followed by urine test using the NarcoCheck® kit for qualitative detection of substances or its metabolites. To assess the diagnostic capability, the participants’ self-responses were compared with their urine test results. The sensitivity, specificity, positive and negative predictive values, and kappa coefficient were also calculated. Results The frequency of lifetime psychoactive substance use according to self-report was 81.5% (95% CI: 0.746–0.873), while over the past three months (recent use) was 52.2% (95% CI: 0.441–0.603) and 58.6% based on the urine test. Alcohol, tobacco and cannabis were the most prevalent psychoactive substance used. The overall concordance between self-reported psychoactive substance use and the urine test (gold standard) was moderate (sensitivity = 66%; kappa = 0.46). Self-report cocaine use compared with urine test showed the highest concordance (sensitivity = 100%; kappa = 79%), followed by tobacco (sensitivity = 58%, kappa = 41%). On an average 70% of urine test results were consistent with self-report (VPP). Participants’ were more accurate when they were reporting no psychoactive substance use as suggested by the high negative predictive value (NPV). Conclusion Diagnostic capability of self-reporting of psychoactive substance use among patients admitted to psychiatric consultations was moderate. Therefore self-reporting may not estimate the exact prevalence of psychoactive substance use. Optimal identification of psychoactive substances use in psychiatric patients requires both history and urine testing. The integration of these two approaches is an excellent method to find out the level, frequency and nature of drug used.

In this paper, the characteristics of the nonlinear dynamics of thermal convection in two nanofluids and their hybrid each confined in an infinite rectangular cavity and heated from below in the presence of vertical magnetic field are studied for volume fractions fixed between 0 and 0.04. The use of the truncated Galerkin approximation made it possible to find a low-dimensional Lorenz system in order to study numerically the transition from natural convection to chaotic behavior. The various results have shown that, for low Rayleigh numbers with or without a magnetic field, the addition of nanoparticles in a base fluid (water) makes it possible to control the chaos; that is, it is possible to suppress or improve the chaotic convection. Also, during each transition, by varying the volume fraction, we notice that the critical Rayleigh number of the base fluid containing the nanoparticle of alumina is greater than that of the fluid containing copper nanoparticle. But for certain values of this volume fraction, the critical Rayleigh number of the base fluid containing copper takes over. On the other hand, for volume fractions fixed between 0 and 0.04 and Rayleigh numbers of the base fluid greater than the critical values, the bifurcation diagrams show that the copper nanofluid makes it possible to quickly switch from chaotic to periodic regimes compared to the alumina nanofluid. The use of hybrid nanoparticles allows further control of the chaos in base fluid such as water by expanding the convective flow and reducing the chaotic flow.

In this paper, an autonomous Morse jerk oscillator which is designed by converting an autonomous two-dimensional Morse oscillator to a jerk oscillator, is analysed. The stability of its unique equilibrium point reveals the existence of Hopf bifurcation. Periodic and chaotic oscillations, antimonotonicity, chaotic bubbles and coexisting attractors are generated in the proposed jerk oscillator. Then, this proposed jerk oscillator is implemented in PSIM software and realized in a printed circuit board to verify the numerical results. The experimental/PSIM results agree well with the numerical simulations. Moreover, it is possible to control partially or totally the amplitude of its signals by introducing two additional parameters in the rate-equations describing the proposed jerk oscillator. Furthermore based on the Routh–Hurwitz conditions and using a single linear feedback controller, the proposed jerk oscillator is controlled to its unique equilibrium point. Finally, the coexistence between periodic and chaotic attractors is destroyed and controlled to a desired trajectory thank to the linear augmentation method.

Aquaculture activities are often established in the vicinity of highly populated, potentially contaminated areas. Animals cultured at such locations, namely bivalves, are frequently used as test organisms in ecotoxicological testing. In this case, a period of depuration is required to allow the normalization of physiological processes, which are likely to be altered after exposure to a multiplicity of waterborne contaminants occurring in the wild. One of the most important species in modern marine aquaculture is the oyster species Crassostrea gigas. The aim of this study was to assess if the current depuration time frame of 24 h (adopted by most aquaculture facilities), is long enough to permit oysters to revert potential toxic effects exerted by environmental contaminants, allowing their use in laboratory-based ecotoxicological studies. The selected approach involved the monitoring of biochemical (antioxidant defence, oxidative damage, phase II metabolism, and neurological homeostasis) and physiological (condition index) parameters, along a period of 42 days. The obtained results showed that a period of 24 h does not revert any of the potential toxic effects caused by environmental contaminants to which animals may have been previously subjected; even a period of 42 days was not long enough for the oysters to completely normalize the levels of their antioxidant defences, namely total GPx activity, which increased over time. Lipid peroxidation was also increased during the depuration period, and the activity of the metabolic isoenzymes GSTs was significantly decreased. Furthermore, AChE activity measured in the adductor muscle of oysters was increased over time. These assumptions suggest that a period of depuration longer than 24 h is mandatory to obtain adequate test organisms of this oyster species, to be used for ecotoxicological testing purposes. published

To develop a deep learning algorithm for automated detection and localization of intracranial aneurysms on time-of-flight MR angiography and evaluate its diagnostic performance. In a retrospective and multicenter study, MR images with aneurysms based on radiological reports were extracted. The examinations were randomly divided into two data sets: training set of 468 examinations and internal test set of 120 examinations. Additionally, 50 examinations without aneurysms were randomly selected and added to the internal test set. External test data set consisted of 56 examinations with intracranial aneurysms and 50 examinations without aneurysms, which were extracted based on radiological reports from a different institution. After manual ground truth segmentation of aneurysms, a deep learning algorithm based on 3D ResNet architecture was established with the training set. Its sensitivity, positive predictive value, and specificity were evaluated in the internal and external test sets. MR images included 551 aneurysms (mean diameter, 4.17 ± 2.49 mm) in the training, 147 aneurysms (mean diameter, 3.98 ± 2.11 mm) in the internal test, 63 aneurysms (mean diameter, 3.23 ± 1.69 mm) in the external test sets. The sensitivity, the positive predictive value, and the specificity were 87.1%, 92.8%, and 92.0% for the internal test set and 85.7%, 91.5%, and 98.0% for the external test set, respectively. A deep learning algorithm detected intracranial aneurysms with a high diagnostic performance which was validated using external data set. • A deep learning-based algorithm for the automated diagnosis of intracranial aneurysms demonstrated a high sensitivity, positive predictive value, and specificity. • The high diagnostic performance of the algorithm was validated using external test data set from a different institution with a different scanner. • The algorithm might be robust and effective for general use in real clinical settings.

Purpose: Pesticide contamination of river waters is a global problem, and therefore, authorities regularly monitor the water quality status. Especially, flood events might transport large pesticide loads downstream and impact adjacent areas such as sensible floodplain environments by deposing particle bound pesticides or by contaminating the environments by dissolved substances directly. Unfortunately, only little attempts were made to quantify the pesticide pollution of such environments, as the monitoring of soil and sediment contamination is by far more time consuming and complicated compared to the analysis of water samples., Materials and methods: In the study presented, we therefore used a holistic approach starting with the reconstruction of the inundation characteristics of a floodplain located in the upper part of the river Elbe, Germany, by using nearby gauging data, screened databases for pesticide concentrations and calculated pesticide loads, and finally, sampled the floodplain soils along an elevation (inundation) gradient., Results: As expected, the reconstructed inundation characteristics showed that the low-lying areas of the backwater inflow of the floodplain were flooded more frequently compared to the areas at higher elevation, whereby even the highest elevations sampled were at least flooded during each decade. Furthermore, pesticide concentrations of the river waters and calculated pesticide loads revealed that 13 pesticides can be found regularly, whereby atrazine, terbuthylazine, metazachlor, metolachlor, isoproturon, and chlorotoluron are the main contaminants., Conclusion: Concluding, a spatial pattern in the contamination could be detected. High residues of simazine and ethofumesate were associated with areas of less and more frequent inundations, respectively. The transformation products of atrazine and terbuthylazine (2-hydroxy-atrazine and 2-hydroxy-terbuthylazine) were detected, whereby the quantity could be well explained by the inundation characteristics and pesticide loads of the river water., Forschungszentrum Jülich GmbH (4205)

Periodic bathymetry surveys are essential to provide data to keep navigation charts updated, obtain insights into water body bottom dynamics and processes, and for hydrodynamic modelling. Frequent bathymetry monitoring has become particularly important in a time of climate variability, which may affect hydrodynamics in yet unknown ways. Bathymetric data are, however, often scarce, because surveys are generally time consuming, expensive and complicated. A methodology combining a low-cost single beam sonar with a dual-frequency differential high-precision GNSS (Global Navigation Satellite System) is presented. Sonar depth measurements and GNSS positions were integrated optimizing sonar and GNSS track overlay. As a result, no physical, electronic link between both devices is needed, and precise positions and depths can be obtained without the need to apply the approach based on tide correction, which always introduces some uncertainty. The methodology was successfully tested and validated, with data collected inside an estuary and offshore the estuarine inlet. Vertical accuracies, assessed at track crossings and on locations of known depths, showed mean squared errors of about 20 cm, suggesting that the method is reliable in providing bathymetric data that satisfy the highest standards of the IHO for hydrographic surveys. Validation results suggest that the effects of boat pitch, roll and yaw on depth measurements were negligible in our survey, which covered depths between 0.4 and 24.5 m below MSL and were carried out in quite calm waters, though larger errors occurred in the off-shore zone. The use of an inertial measurement unit (IMU), which can easily be coupled with the GNSS to extract ship motion data and correct depths accordingly, is advised for less optimal survey conditions and deeper waters. The proposed method is accurate, simple and affordable, allowing for more frequent surveys and a better coverage of dynamic shallow water systems such as rivers and estuaries.

BACKGROUND: Long-lasting insecticidal nets (LLINs) are currently the primary method of malaria control in sub-Saharan Africa and have contributed to a significant reduction in malaria burden over the past 15 years. However, this progress is threatened by the wide-scale selection of insecticide-resistant malaria vectors. It is, therefore, important to accelerate the generation of evidence for new classes of LLINs. METHODS: This protocol presents a three-arm superiority, single-blinded, cluster randomized controlled trial to evaluate the impact of 2 novel dual-active ingredient LLINs on epidemiological and entomological outcomes in Benin, a malaria-endemic area with highly pyrethroid-resistant vector populations. The study arms consist of (i) Royal Guard® LLIN, a net combining a pyrethroid (alpha-cypermethrin) plus an insect growth regulator (pyriproxyfen), which in the adult female is known to disrupt reproduction and egg fertility; (ii) Interceptor G2® LLIN, a net incorporating two adulticides (alpha-cypermethrin and chlorfenapyr) with different modes of action; and (iii) the control arm, Interceptor® LLIN, a pyrethroid (alpha-cypermethrin) only LLIN. In all arms, one net for every 2 people will be distributed to each household. Sixty clusters were identified and randomised 1:1:1 to each study arm. The primary outcome is malaria case incidence measured over 24 months through active case detection in a cohort of 25 children aged 6 months to 10 years, randomly selected from each cluster. Secondary outcomes include 1) malaria infection prevalence (all ages) and prevalence of moderate to severe anaemia in children under 5 years old, measured at 6 and 18 months post-intervention; 2) entomological indices measured every 3 months using human landing catches over 24 months. Insecticide resistance intensity will also be monitored over the study period. DISCUSSION: This study is the second cluster randomised controlled trial to evaluate the efficacy of these next-generation LLINs to control malaria transmitted by insecticide-resistant mosquitoes. The results of this study will form part of the WHO evidence-based review to support potential public health recommendations of these nets and shape malaria control strategies of sub-Saharan Africa for the next decade. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03931473 , registered on 30 April 2019.

This work concerns the modelling of the dynamics of polarisation of a centrosymmetric material subjected to an amplitude-modulated excitation (AME). The dynamic equation obtained for the polarisation is the Duffing equation with nonlinearities of orders 3 and 5. With the multiple scale method, the nonlinear resonances are studied. Periodic, multiperiodic, quasiperiodic and chaotic behaviour have been checked using the bifurcation diagram, Lyapunov exponent, phase space, Poincare section and vibrational resonance using the fourth-order Runge–Kutta integration algorithm. The effects of various parameters of polarisation are analysed and very interesting results are obtained. The results obtained by the analytical methods are validated and complemented by the numerical simulations.

In this paper, an autonomous three-dimensional Helmholtz-type oscillator is designed based on conversion of an autonomous Helmholtz two-dimensional oscillator to a jerk oscillator. For a suitable choice of the parameters, the proposed autonomous Helmholtz jerk oscillator can generate Hopf bifurcation, bistable period-2 limit cycles, two types of one-scroll chaotic attractors and coexistence between period-3 limit cycle and one-scroll chaotic attractors. Using a weak modulation of a parameter of the proposed Helmholtz jerk oscillator, it is possible to destroy the coexisting attractors found and transform the proposed Helmholtz jerk oscillator to period-3 oscillations. Moreover using experiments and OrCAD-PSpice software, circuit implementation of the proposed autonomous Helmholtz jerk oscillator is realized in order to check the one-scroll chaotic attractors and the coexisting attractors found during the numerical simulations. Numerical and experimental/OrCAD-PSpice results have a good qualitative agreement. Finally, by adding two new parameters in the proposed autonomous Helmholtz jerk oscillator, it is possible to control the amplitude of the attractor and the largest Lyapunov exponent.

The combination of photodynamic therapy (PDT) with anti-tumor agents is a complimentary strategy to treat local cancers. We developed a unique photosensitizer (PS)-conjugated paclitaxel (PTX) prodrug in which a PS is excited by near-infrared wavelength light to site-specifically release PTX while generating singlet oxygen (SO) to effectively kill cancer cells with both PTX and SO. The aim of the present study was to identify the determinants influencing the combined efficacy of this light-activatable prodrug, especially the bystander killing effects from released PTX. Using PS-conjugated PTX as a model system, we developed a quantitative mathematical model describing the intracellular trafficking. Dynamics of the prodrug and the model predictions were verified with experimental data using human cancer cells in vitro. The sensitivity analysis suggested that parameters related to extracellular concentration of released PTX, prodrug uptake, target engagement, and target abundance are critical in determining the combined killing efficacy of the prodrug. We found that released PTX cytotoxicity was most sensitive to the retention time of the drug in extracellular space. Modulating drug internalization and conjugating the agents targeted to abundant receptors may provide a new strategy for maximizing the killing capacity of the far-red light-activatable prodrug system. These results provide guidance for the design of the PDT combination study in vivo and have implications for other stimuli-responsive drug delivery systems.

To investigate the difference in amide proton transfer (APT)-weighted signals between benign and atypical meningiomas and determine the value of APT imaging for differentiating the two. Fifty-seven patients with pathologically diagnosed meningiomas (benign, 44; atypical, 13), who underwent preoperative MRI with APT imaging between December 2014 and August 2016 were included. We compared normalised magnetisation transfer ratio asymmetry (nMTR asym ) values between benign and atypical meningiomas on APT-weighted images. Conventional MRI features were qualitatively assessed. Both imaging features were evaluated by multivariable logistic regression analysis. The discriminative value of MRI with and without nMTR asym was evaluated. The nMTR asym of atypical meningiomas was significantly greater than that of benign meningiomas (2.46% vs. 1.67%; P

Tree roots penetrate the soil to several meters depth, but the role of subsoils for the supply of nutrient elements such as phosphorus (P) to the trees is poorly understood. Here, we tested the hypothesis that increased P deficiency in the topsoil results in an increased microbial recycling of P from the forest subsoil. We sampled soils from four German temperate forest sites representing a gradient in total P stocks. We analyzed the oxygen isotopic composition of HCl-extractable phosphate (δ18OP) and identified differences in P speciation with increasing soil depth using X-ray absorption near-edge structure (XANES) spectroscopy. We further determined microbial oxygen demand with and without nutrient supply at different soil depths to analyse nutrient limitation of microbial growth and used nanoscale secondary ion mass spectrometry (NanoSIMS) to visualize spatial P gradients in the rhizosphere. We found that δ18OP values in the topsoil of all sites were close to the isotopic signal imparted by biological cycling when oxygen isotopes in phosphate are exchanged by enzymatic activity. However, with increasing soil depth and increasing HCl-P concentrations, δ18Ο values continuously decreased towards values expected for primary minerals in parent material at depths below 60 cm at sites with high subsoil P stocks and below more than 2 m at sites with low subsoil P stocks, respectively. For these depths, XANES spectra also indicated the presence of apatite. NanoSIMS images showed an enrichment of P in the rhizosphere in the topsoil of a site with high P stocks, while this P enrichment was absent at a site with low P stocks and in both subsoils. Addition of C, N and P alone or in combination revealed that microbial activity in subsoils of sites with low P stocks was mostly P limited, whereas sites with high P stocks indicated N limitation or N and P co-limitation. We conclude that subsoil P resources are recycled by trees and soil microorganisms. With continued weathering of the bedrock and mobilisation of P from the weathered rocks, P cycling will proceed to greater depths, especially at sites characterised by P limitation., Biogeochemistry, 150 (3), ISSN:0168-2563, ISSN:1573-515X