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Hydraulic modelling of natural floodplain vegetation using leaf area index (LAI) has been applied successfully for non-submerged conditions whereas its suitability for submerged conditions requires further development. This study investigates the vegetative flow resistance at low relative submergences and extends existing LAI-based approaches building upon new flume data and prior experiences from field-scale applications. We provide advanced LAI-based formulas for modelling the flow resistance from emergent to submerged conditions, with water depth up to three times higher than the vegetation height. Such low relative submergences are highly relevant in hydraulic analyses of riverbank and floodplain flows but not adequately represented in existing formulas. The use of the deflected vegetation height as the characteristic height provided the most accurate modelling results, whereas the use of undeflected height resulted in significant errors. As a new development for submerged conditions, we proposed von Kármán scaling factor for improved model predictions. Overall, the results proved that LAI-based modelling is suitable also at low relative submergences for a wide range of vegetation densities (LAI = 1–5) and mean flow velocities (0.05–1.2 m s−1). For both emergent and slightly overtopped vegetation the JAR and VAS approaches outperformed the BAPmod-LAI approach that does not account for reconfiguration. For modellers, we provide a workflow and guidance on the use of the newly developed LAI-based formulas in 1D/2D hydrodynamic models for both emergent and submerged conditions. [ABSTRACT FROM AUTHOR]

Reach-scale experiments simulating the physical characteristics of natural woody plants are required for the improved modeling of flow resistance in channels with instream and floodplain vegetation. The first aim of this study was to investigate the flow resistance caused by patches of foliated woody vegetation at low volumetric blockage factors (4% to 10%) under emergent conditions, as most studies on the effect of patchiness are limited to submerged aquatic plants. Experiments with nature-like willow patches were performed in a reach-scale outdoor flume, where the density and layout of the patches were altered. The bulk friction factors were based on the friction slopes, calculated using the water surface slopes and velocity heads measured by a set of high-accuracy pressure sensors under several flow conditions. Compared to unvegetated conditions, the patches increased the bulk friction factor by 1.7–5.5 times, depending on the patch density and blockage factor. The second aim of this study was to evaluate the performance of four momentum-based models in estimating the bulk friction factors in flows with such flexible patches. For this process, a methodological approach suited for patchy woody vegetation at reach scale was developed to determine the input parameters required in each model. Estimation results using the newly modified and parameterized formulas compared favorably to the experimental data, demonstrating more reliable performance for models explicitly addressing the reconfiguration of vegetation. Overall, this study provides a practical methodology for estimating flow resistance caused by complex distributions of woody riverine vegetation. [ABSTRACT FROM AUTHOR]

Background Although there is a relationship between the extent of striatal dopaminergic defect and the severity of motor symptoms in Parkinson's disease (PD), studies investigating associations between dopamine and mortality in PD have been scarce. If a relationship were established, dopamine restoring neuroprotective treatments could be used to decrease mortality. The objective of this study was to determine whether the initial degree of hypodopaminergic defect, as measured by 6-[ 18 F]fluoro-L-DOPA positron emission tomography (FDOPA-PET), can predict patient survival. Methods The study population included a cohort of 88 recently diagnosed and untreated patients with PD who were clinically examined and scanned with FDOPA-PET between the years 1998 and 2000. The date of exit for the survival analysis was in April 2013 with a follow-up interval of 13-15 years. The survival model included FDOPA uptake, age, sex and symptom severity as explaining factors. Death certificates of the patients were obtained, and causes of death were analyzed. Results Mortality rate was 56.8%. Although higher age ( p < 0.001) and greater motor symptom severity ( p < 0.05) were associated with increased mortality, there was no association between survival and FDOPA uptake in any striatal subregion ( p > 0.48). Conclusion Unlike age and early motor symptom severity, dopamine synthesis capacity, as measured with PET, does not predict survival in PD. [ABSTRACT FROM AUTHOR]

Highlights: [•] New insights into the flow resistance of foliated vegetation were obtained. [•] We measured drag and alternative reference areas for natural poplars in a flume. [•] Partly and just submerged plants had similar drag and frontal area per reference area. [•] Drag and reconfiguration were controlled by the foliage–stem reference area ratio. [•] The alternative reference areas satisfactorily predicted the drag and flow resistance. [ABSTRACT FROM AUTHOR]

This paper summarizes current practices for the estimation of flow resistance caused by floodplain vegetation in emergent flow conditions. The current state-of-the-art for the parameterization of vegetative form drag and associated flow resistance was explored with a view on practical applicability. Specifically, the dissimilar resistance behaviour of simply shaped rigid elements and foliated natural vegetation was emphasized by compiling and reanalysing data published by the authors’ research teams as well as others. It was shown that describing the key hydraulic properties of plants, geometry, and flexibility, with species-specific parameters is superior to the rigid cylinder analogy commonly used in hydraulic engineering practice. The discussion on the limitations of many existing approaches for the determination of vegetative flow resistance is intended to advance the use of modern practices such as the parameterization of vegetation density with the leaf area index, a parameter that can be derived using remote sensing techniques. [ABSTRACT FROM AUTHOR]

Design of environmentally preferable agricultural drainage channels calls for an improved understanding of cohesive sediment processes. Flow and cohesive sediments were investigated in a new demonstration and test channel where a floodplain was excavated on one side of the existing channel to improve flood conveyance. In this approach, the existing, naturally recovered channel was mostly left intact to reduce environmental impacts. Continuous monitoring of discharge and suspended sediment concentration (SSC) during 1 year revealed that the construction work of the two-stage channel caused 2% of the annual suspended sediment (SS) load. Agricultural areas covering 13% of the catchment were estimated to contribute over half of the annual SS, predominantly during the rising stages. Seasonal positive hysteresis was found in SSC which was explained by different drainage efficiencies of two distinct sediment sources. The temporally varying shares of the two sources caused scatter in the rating curves between discharge and SSC or SS load. Out-of-channel processes were shown to govern the amount and timing of the SS input into the channel, indicating that environmentally preferable agricultural channel design should consider the cohesive sediment processes and sources at the catchment scale. [ABSTRACT FROM PUBLISHER]

Abstract: In the postnatal rodent hippocampus status epilepticus (SE) leads to age- and region-specific excitotoxic neuronal damage, the precise mechanisms of which are still incompletely known. Recent studies suggest that the activation of inflammatory responses together with glial cell reactivity highly contribute to excitotoxic neuronal damage. However, pharmacological tools to attenuate their activation in the postnatal brain are still poorly elucidated. In this study, we investigated the role of inflammatory mediators in kainic acid (KA)-induced neuronal damage in organotypic hippocampal slice cultures (OHCs). A specific cyclooxygenase-2 (COX-2) inhibitor N-[2-(cyclohexyloxy)-4-nitrophenyl]-methanesulfonamide (NS-398) was used to study whether or not it could ameliorate neuronal death. Our results show that KA treatment (24 h) resulted in a dose-dependent degeneration of CA3a/b pyramidal neurons. Furthermore, COX-2 immunoreactivity was pronouncedly enhanced particularly in CA3c pyramidal neurons, microglial and astrocyte morphology changed from a resting to active appearance, the expression of the microglial specific protein, Iba1, increased, and prostaglandin E2 (PGE2) production increased. These indicated the activation of inflammatory processes. However, the expression of neither proinflammatory cytokines, i.e. tumour necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β), nor the anti-inflammatory cytokine IL-10 mRNA was significantly altered by KA treatment as studied by real-time PCR. Despite activation of an array of inflammatory processes, neuronal damage could not be rescued either with the combined pre- and co-treatment with a specific COX-2 inhibitor, NS-398. Our results suggest that KA induces activation of a repertoire of inflammatory processes in immature OHCs, and that the timing of anti-inflammatory treatment to achieve neuroprotection is a challenge due to developmental properties and the complexity of inflammatory processes activated by noxious stimuli. This article is part of a Special Issue entitled ‘Trends in Neuropharmacology: In Memory of Erminio Costa’. [Copyright &y& Elsevier]

Abstract: Cross-flooding ducts are used to equalize asymmetric flooding and, thus, to decrease the heel angle of a ship in an emergency. The present design guidelines for cross-flooding arrangements involve uncertainties associated with the effect of variable structural factors. In this study, scale model experiments were carried out to determine discharge coefficients of a typical cross-duct, with a focus on the effect of structural components such as the girders, stiffeners, and web frame. Flow conditions and configuration of the components were varied in the experiments. The structural stiffeners in the cross-duct were found to notably increase the discharge coefficient whereas the effects of the web frame and the inclination of the duct at an angle of 7° were negligible. The experimentally obtained discharge coefficient values for the cross-duct were considerably lower than the corresponding values computed according to the generally used guidelines of the IMO Resolution MSC.245(83). This indicates that the geometrical properties of the girders in the cross-ducts need to be properly addressed to avoid overestimating the discharge coefficients. Overall, the experimental results formed an indispensable dataset for the validation and further development of CFD approaches. [Copyright &y& Elsevier]

Background: Status epilepticus (SE) is proposed to lead to an age-dependent acute activation of a repertoire of inflammatory processes, which may contribute to neuronal damage in the hippocampus. The extent and temporal profiles of activation of these processes are well known in the adult brain, but less so in the developing brain. We have now further elucidated to what extent inflammation is activated by SE by investigating the acute expression of several cytokines and subacute glial reactivity in the postnatal rat hippocampus. Methods: SE was induced by an intraperitoneal (i.p.) injection of kainic acid (KA) in 9- and 21-day-old (P9 and P21) rats. The mRNA expression of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), matrix metalloproteinase-9 (MMP-9), glial-derived neurotrophic factor (GDNF), interferon gamma (IFN-γ), and transforming growth factor-beta 1 (TGF-b1) were measured from 4 h up to 3 days after KA injection with real-time quantitative PCR (qPCR). IL-1β protein expression was studied with ELISA, GFAP expression with western blotting, and microglial and astrocyte morphology with immunohistochemistry 3 days after SE. Results: SE increased mRNA expression of IL-1β, TNF-α and IL-10 mRNA in hippocampus of both P9 and P21 rats, their induction being more rapid and pronounced in P21 than in P9 rats. MMP-9 expression was augmented similarly in both age groups and GDNF expression augmented only in P21 rats, whereas neither IFN-γ nor TGF-β1 expression was induced in either age group. Microglia and astrocytes exhibited activated morphology in the hippocampus of P21 rats, but not in P9 rats 3 d after SE. Microglial activation was most pronounced in the CA1 region and also detected in the basomedial amygdala. Conclusion: Our results suggest that SE provokes an age-specific cytokine expression in the acute phase, and agespecific glial cell activation in the subacute phase as verified now in the postnatal rat hippocampus. In the juvenile hippocampus, transient increases in cytokine mRNA expression after SE, in contrast to prolonged glial reactivity and region-specific microglial activity after SE, suggest that the inflammatory response is changed from a fulminant and general initial phase to a more moderate and specific subacute response. [ABSTRACT FROM AUTHOR]

• Novel flume setup combining high-accuracy pressure and force sensors. • Extension of LAI-based modelling of vegetative resistance to low and high densities. • Flow resistance contribution by the understory grasses should not be neglected. River flows are greatly influenced by floodplain vegetation with implications on hydrological and hydraulic conditions from cross-sectional to river reach scales. Flow models need to reliably reflect changes in the riverine environment, such as vegetation growth associated with altered flow regimes, increased sediment loads and eutrophication. Leaf area index (LAI) based approaches are increasingly used as tools to predict the flow resistance caused by natural vegetation. However, current LAI-based modelling involves uncertainty at low and high vegetation densities and flow velocities due to a lack of research and validation at the outer ranges. The aim of this paper is to investigate the flow resistance for a mixture of flexible floodplain vegetation consisting of woody plants and understory grasses of low to high densities (LAI = 1–5) over a wide range of mean flow velocities (0.05–1.2 m/s) at low relative submergences of 1–2. A novel flume setup was designed by using high-accuracy pressure sensors to measure flow resistance and force sensors to measure plant drag forces. Flow resistance decreased by 35–90% when the submergence H / h v increased from 1 to 2, which is a highly relevant range for floodplain flows. The results provided new evidence that LAI-based modelling of vegetative friction factors can be reliably extended from low to high LAI values for non-submerged vegetation. However, adjustments to existing LAI-based approaches are required for water stages higher than the vegetation height. Furthermore, the friction by the understory grasses cannot be neglected as often assumed in literature especially for cases of low plant densities and low relative submergences. [ABSTRACT FROM AUTHOR]

Epileptic seizures lead to age-dependent neuronal damage in the developing brain, particularly in the hippocampus, but the mechanisms involved have remained poorly elucidated. In this study, we investigated the contribution of apoptosis and inflammatory processes to neuronal damage after status epilepticus (SE) in postnatal rats. SE was induced by an intraperitoneal injection of kainic acid (KA) in 21- and 9-day-old (P21 and P9) rats. The expression of Bax, Bcl-2 and caspase-3, markers for apoptosis, and cyclooxygenase-2 (COX-2), an indicator for activation of inflammatory processes, were studied from 6 h up to 1 week after SE by Western blotting and immunocytochemistry. Neuronal damage was verified by Fluoro-Jade B staining. In P21 rats, SE resulted in neuronal damage in the CA1 neurons of the hippocampus. COX-2 expression was extensively, but transiently, increased and its immunoreactivity pronouncedly enhanced in several hippocampal subregions, amygdala, and piriform cortex by 24 h after SE. The expression of Bax and caspase-3 remained unchanged, whereas the antiapoptotic factor Bcl-2 transiently decreased by 24 h. Single caspase-3 positive neurons appeared in the CA1 region of both control and KA-treated rats. In P9 rats, no neuronal death was detected, and COX-2 expression and immunoreactivity remained at the control level. Our results suggest that SE provokes age-specific effects on COX-2 expression. This together with the activation of putative inflammatory processes may contribute to neuronal cell death in the hippocampus of postnatal rats, whereas caspase-dependent apoptosis seems not to be involved in the death process. [ABSTRACT FROM AUTHOR]

Abstract: Flume studies were carried out to investigate flow structure above flexible vegetation. A new data set of mean velocity profiles and turbulence characteristics is reported from experiments with wheat. The flow above the wheat reasonably followed the log law. Maximum values of the turbulence intensity u rms and Reynolds stress were found approximately at the level of the maximum observed deflected plant height. A recent approach for describing vertical velocity profiles above aquatic vegetation [Stephan, U., 2002. Zum Fließwiderstandsverhalten flexibler Vegetation. Wiener Mitteilungen 180. Doctoral Thesis. Institute of Hydraulics, Hydrology and Water Resources Management, Faculty of Civil Engineering, Technical University of Vienna.] was evaluated with these new data, which represent a different vegetal roughness type. The approach proved to be successful beyond the original scope. However, a new definition for the shear velocity based on the deflected plant height is suggested. The benefit of this modification is that complex turbulence measurements can be avoided, which enhances the practical applicability of the approach. [Copyright &y& Elsevier]

Flow resistance of natural grasses, sedges and willows was studied in a laboratory flume. The objective was to investigate, how type, density and placement of vegetation, flow depth and velocity influence friction losses. The plants were studied in various combinations under nonsubmerged and submerged conditions in a total of 350 test runs. The results show large variations in the friction factor, f, with depth of flow, velocity, Reynolds number, and vegetative density. The friction factor was dependent mostly on (1) the relative roughness in the case of grasses; (2) the flow velocity in the case of willows and sedges/grasses combined; and (3) the flow depth in the case of leafless willows on bare bottom soil. Leaves on willows seemed to double or even triple the friction factor compared to the leafless case despite the fact that the bottom was growing sedges in both cases. For the leafless willows, f appeared to increase with depth almost linearly and independently of velocity. Unexpectedly, different spacing of the same number of leafless willows with grasses did not have any significant effect on f. Based on the experimental work, a better understanding of flow resistance due to different combinations of natural stiff and flexible vegetation under nonsubmerged and submerged conditions was gained. [Copyright &y& Elsevier]

• Experiments on flow resistance of foliated woody vegetation patches at reach-scale. • Reach-scale flow resistance controlled by patch geometry, less by canopy density. • Quantitative relationships for predicting flow resistance using blockage factors. Woody riparian vegetation typically clusters in patch form and increases flow resistance more significantly than individual plants. In this study, we examined the patchiness effects in non-submerged (emergent) conditions on the reach-scale flow resistance in field-scale experiments involving nature-like artificial willow patches. The patchiness characteristics of woody vegetation were systematically defined and classified using the canopy density, patch geometry described by cross-sectional and planar blockage areas, cross-sectional and volumetric blockage factors of the patches, and patch location in the cross-section. We developed quantitative relationships as empirical equations for estimating the vegetative flow resistance using blockage factors, that is, the area or volume fraction of canopy occupation. The results revealed that flow resistance due to emergent willow patches under relatively densely foliated and low volumetric blockage conditions was mostly explained by the blockage parameters and to a lower degree by the canopy density. In addition, it reveals the effects of the spatial distribution of flow and velocity by the relative position of patches, i.e., the flow resistance varies with different tendencies according to hydraulic conditions as the patch shifts from the channel centerline toward the bankside. This study provides reliable and practical relationships for estimating the flow resistance induced by riparian vegetation patches under reach-scale field conditions. [ABSTRACT FROM AUTHOR]

Abstract Riparian shrubs and trees present a complex, seasonally variable morphology, with flexible stems and leaves efficiently adapting to the flow forcing (reconfiguration). The aim of this paper is to investigate how foliage and reconfiguration affect the flow and mixing in a partly vegetated channel. Specific attention was placed on the velocity statistics, onset and coherence of turbulent structures, and lateral momentum transport at the horizontal interface between vegetation and open water. The experimental flume arrangement was novel in that it allowed investigating the lateral shear layer induced by flexible riparian plants. The natural-like vegetation consisted of emergent woody plants and a grassy understory, with density, morphology and reconfiguration behavior comparable to those found in real riparian areas. Investigations were conducted under foliated and leafless conditions to determine the seasonality effects. The mean and turbulent flow structure was determined with acoustic Doppler velocimetry, and dynamic plant motions were investigated from video footage. The presence of foliage enhanced the drag discontinuity at the interface, resulting in more pronounced velocity gradients between the vegetated and open areas compared to the leafless conditions. Foliation induced stronger shear layer-scale mixing, whereas, under leafless conditions, the local mixing induced by stems was more important. The reconfiguration decreased the coherence of the two-dimensional large-scale vortices at the interface while their characteristic frequency was consistent with the canonical mixing layer theory. Our results indicated that shear layer dynamics in partly vegetated channels was influenced strongly by morphology and reconfiguration of complex plants, with more efficient lateral momentum transport at the interface in the foliated conditions than previously reported for shear layers induced by simpler vegetation. [ABSTRACT FROM AUTHOR]

This paper investigates the structural properties of four common riparian tree species and their reconfiguration under hydrodynamic loading in a towing tank in foliated and defoliated conditions. 3D tree models were generated by digitizing twenty 0.8–3.3 m tall specimens at branch level. Branch diameters and lengths were measured in order to calculate the one-sided stem area and stem volume over the plant height. The novelty of the investigations originated from the characterization of the reconfiguration which was achieved by combining the contracted width, the deflected height, and the underwater projected area in order to determine the porosity at different velocities. The results showed that the basal diameter could be used to predict the entire total one-sided stem area, although this method was not capable of reproducing the observed non-linear vertical distributions. The flow-induced width contraction contributed significantly to the reduction of the rectangular cross-sectional area occupied by the plant. The porosity of the foliated trees increased at the lower velocities, and then decreased at the higher velocities. Overall, detailed spatial–structural analyses of woody vegetation provided valuable information about plant behaviour under load, and thus are helpful for improving the determination of the physically based parameters of complex vegetative elements which is highly relevant for environmental modelling in order to fill the gap of knowledge concerning the hydrodynamic and aerodynamic flow around trees. [ABSTRACT FROM AUTHOR]

Introduction: The Unified Dyskinesia Rating Scale (UDysRS) was developed to provide a comprehensive rating tool of dyskinesia in Parkinson's disease (PD). Because dyskinesia therapy trials involve multicenter studies, having a scale that is validated in multiple non-English languages is pivotal to international efforts to treat dyskinesia. The aim of the present study was to organize and perform an independent validation of the UDysRS Finnish version. Methods: The UDysRS was translated into Finnish and then back-translated into English using 2 independent teams. Cognitive pretesting was conducted on the Finnish version and required modifications to the structure or wording of the translation. The final Finnish version was administered to 250 PD patients whose native language is Finnish. The data were analyzed to assess the confirmatory factor structure to the Spanish UDysRS (the reference standard). Secondary analyses included an exploratory factor analysis (EFA), independent of the reference standard. Results: The comparative fit index (CFI), in comparison with the reference standard factor structure, was 0.963 for Finnish. In the EFA, where variability from sample to sample is expected, isolated item differences of factor structure were found between the Finnish and Reference Standard versions of the UDysRS. These subtle differences may relate to differences in sample composition or variations in disease status. Conclusion: The overall factor structure of the Finnish version was consistent with that of the reference standard, and it can be designated as the official version of the UDysRS for Finnish speaking populations. [ABSTRACT FROM AUTHOR]

Mobile mapping systems (MMSs) are used for mapping topographic and urban features which are difficult and time consuming to measure with other instruments. The benefits of MMSs include efficient data collection and versatile usability. This paper investigates the data processing steps and quality of a boat-based mobile mapping system (BoMMS) data for generating terrain and vegetation points in a river environment. Our aim in data processing was to filter noise points, detect shorelines as well as points below water surface and conduct ground point classification. Previous studies of BoMMS have investigated elevation accuracies and usability in detection of fluvial erosion and deposition areas. The new findings concerning BoMMS data are that the improved data processing approach allows for identification of multipath reflections and shoreline delineation. We demonstrate the possibility to measure bathymetry data in shallow (0-1 m) and clear water. Furthermore, we evaluate for the first time the accuracy of the BoMMS ground points classification compared to manually classified data. We also demonstrate the spatial variations of the ground point density and assess elevation and vertical accuracies of the BoMMS data. [ABSTRACT FROM AUTHOR]