Different ways to success: Plant community trajectories over time and a soil moisture gradient in restored wetlands

Ecological restoration is one of the most promising strategies to combat historical wetland losses caused by land use changes. Restored areas are ideal sites to study plant succession and changes in ecosystem functions over time. However, little is known about the influence of restoration on plant succession along environmental stress gradients. Knowing the processes and mechanisms driving the succession over time in contrasting abiotic conditions might provide new insight into the ultimate success of an ecological restoration. Relying on long-term vegetation monitoring, we studied the community succession of 4 plant communities along a restored waterlogging gradient in North-East Italy (from high to low soil saturation level): (i) Cladium fens, (ii) low alkaline fens, (iii) Molina wet meadows and (iv) dry meadows. We monitored 23 permanent plots distributed along the gradient, spanning from 1 to 21 years since restoration, and 4 plots as target vegetation (natural habitats). We analysed the changes in plant communities in terms of functional traits, diversity and species composition. We found that exotic and annual species decreased in mature stages of restoration while leaf dry matter content increased over time. Nutrient indicator value and leaf area showed opposite trends at the extreme points of the gradient. Across the successional stages, species richness decreased in Cladium fens and increased in alkaline fens and meadows. Species composition moved toward target vegetation showing contrasting dynamics between different restored habitats. Synthesis and applications. During succession waterlogging stress acts as main abiotic filter, triggering contrasting trajectories of plant communities. This filter seems to be stronger at the extreme points of the gradient generating opposite but faster dynamics than at intermediate conditions. Time and waterlogging promoted a continuous selection of species consistent to target vegetation in terms of richness, functional traits and composition. The evidenced trajectories suggest the need to develop habitat-specific protocols concerning the selection of restoration site and subsequent management decisions, with particular regard to plant communities at intermediate ecological conditions

Polynomial cases of the tarification problem

We consider the problem of determining a set of optimal tariffs for an agent in a network, who owns a subset of the arcs of the network, and who wishes to maximize his revenues on this subset from a set of clients that make use of the network.The general variant of this problem is NP-hard, already with a single client. This paper introduces several new polynomially solvable special cases. An important case is the following.For multiple clients, if the number of tariff arcs is bounded from above, we can solve the problem by a polynomial number of linear programs (each of which is of polynomial size). Furthermore, we show that the parametric tarification problem and the single arc fixed charge tarification problem can be solved in polynomial time.Economics ;

Bayesian neural network modeling and hierarchical MPC for a tendon-driven surgical robot with uncertainty minimization

In order to guarantee precision and safety in robotic surgery, accurate models of the robot and proper control strategies are needed. Bayesian Neural Networks (BNN) are capable of learning complex models and provide information about the uncertainties of the learned system. Model Predictive Control (MPC) is a reliable control strategy to ensure optimality and satisfaction of safety constraints. In this work we propose the use of BNN to build the highly nonlinear kinematic and dynamic models of a tendon-driven surgical robot, and exploit the information about the epistemic uncertainties by means of a Hierarchical MPC (Hi-MPC) control strategy. Simulation and real world experiments show that the method is capable of ensuring accurate tip positioning, while satisfying imposed safety bounds on the kinematics and dynamics of the robot

Hepatic natural killer cells: Organ-specific sentinels of liver immune homeostasis and physiopathology

The liver is considered a preferential tissue for NK cells residency. In humans, almost 50% of all intrahepatic lymphocytes are NK cells that are strongly imprinted in a liver-specific manner and show a broad spectrum of cellular heterogeneity. Hepatic NK (he-NK) cells play key roles in tuning liver immune response in both physiological and pathological conditions. Therefore, there is a pressing need to comprehensively characterize human he-NK cells to better understand the related mechanisms regulating their effector-functions within the dynamic balance between immune-tolerance and immune-surveillance. This is of particular relevance in the liver that is the only solid organ whose parenchyma is constantly challenged on daily basis by millions of foreign antigens drained from the gut. Therefore, the present review summarizes our current knowledge on he-NK cells in the light of the latest discoveries in the field of NK cell biology and clinical relevance

ZMP Constraint Restriction for Robust Gait Generation in Humanoids

We present an extension of our previously proposed IS-MPC method for humanoid gait generation aimed at obtaining robust performance in the presence of disturbances. The considered disturbance signals vary in a range of known amplitude around a mid-range value that can change at each sampling time, but whose current value is assumed to be available. The method consists in modifying the stability constraint that is at the core of IS-MPC by incorporating the current mid-range disturbance, and performing an appropriate restriction of the ZMP constraint in the control horizon on the basis of the range amplitude of the disturbance. We derive explicit conditions for recursive feasibility and internal stability of the IS-MPC method with constraint modification. Finally, we illustrate its superior performance with respect to the nominal version by performing dynamic simulations on the NAO robot

Visual servoing for path reaching with nonholonomic robots

International audienceWe present two visual servoing controllers (pose-based and image-based) en- abling mobile robots with a fixed pinhole camera to reach and follow a contin- uous path drawn on the ground. The first contribution is the theoretical and experimental comparison between pose-based and image-based techniques for a nonholonomic robot task. Moreover, our controllers are appropriate not only for path following, but also for path reaching, a problem that has been rarely tackled in the past. Thirdly, in contrast with most works, which require the path geometric model, only two path features are necessary in our image-based scheme, and three in the pose-based scheme. For both controllers, a conver- gence analysis is carried out, and the performance is validated by simulations, and outdoor experiments on a car-like robot

Costimulatory Molecules and Immune Checkpoints Are Differentially Expressed on Different Subsets of Dendritic Cells

Dendritic cells (DCs) play a crucial role in initiating and shaping immune responses. The effects of DCs on adaptive immune responses depend partly on functional specialization of distinct DC subsets, and partly on the activation state of DCs, which is largely dictated by environmental signals. Fully activated immunostimulatory DCs express high levels of costimulatory molecules, produce pro-inflammatory cytokines, and stimulate T cell proliferation, whereas tolerogenic DCs express low levels of costimulatory molecules, produce immunomodulatory cytokines and impair T cell proliferation. Relevant to the increasing use of immune checkpoint blockade in cancer treatment, signals generated from inhibitory checkpoint molecules on DC surface may also contribute to the inhibitory properties of tolerogenic DCs. Yet, our knowledge on the expression of inhibitory molecules on human DC subsets is fragmentary. Therefore, in this study, we investigated the expression of three immune checkpoints on peripheral blood DC subsets, in basal conditions and upon exposure to pro-inflammatory and anti-inflammatory stimuli, by using a flow cytometric panel that allows a direct comparison of the activatory/inhibitory phenotype of DC-lineage and inflammatory DC subsets. We demonstrated that functionally distinct DC subsets are characterized by differential expression of activatory and inhibitory molecules, and that cDC1s in particular are endowed with a unique immune checkpoint repertoire characterized by high TIM-3 expression, scarce PD-L1 expression and lack of ILT2. Notably, this unique cDC1 repertoire was subverted in a group of patients with myelodysplastic syndromes included in the study. Applied to the characterization of DCs in the tumor microenvironment, this panel has the potential to provide valuable information to be used for investigating the role of DC subsets in cancer, guiding DC-targeting treatments, and possibly identifying predictive biomarkers for clinical response to cancer immunotherapy

Impact of COVID-19 pandemic lockdown on narcolepsy type 1 management

Study Objectives: Narcolepsy type 1 (NT1) is a chronic rare hypersomnia of central origin requiring a combination of behavioral and pharmacological treatments. During the coronavirus disease 2019 (COVID-19) pandemic, in Italy the population was forced into a lockdown. With this study, we aimed to describe the lockdown impact on NT1 symptom management, according to different patients' working schedule. Methods: In the period between 10 April and 15 May 2020, we performed routine follow-up visits by telephone (as recommended during the COVID-19 emergency) to 50 patients >18 years old (40% males) under stable long-term treatment. We divided patients into three groups: unchanged working schedule, forced working/studying at home, and those who lost their job (“lost occupation”). Current sleep–wake habit and symptom severity were compared with prelockdown assessment (six months before) in the three patient groups. Results: At assessment, 20, 22, and eight patients belonged to the unchanged, working/studying at home, and lost occupation groups, respectively. While in the lost occupation group, there were no significant differences compared with prepandemic assessment, the patients with unchanged schedules reported more nocturnal awakenings, and NT1 patients working/studying at home showed an extension of nocturnal sleep time, more frequent daytime napping, improvement of daytime sleepiness, and a significant increase in their body mass index. Sleep-related paralysis/hallucinations, automatic behaviors, cataplexy, and disturbed nocturnal sleep did not differ. Conclusions: Narcolepsy type 1 patients working/studying at home intensified behavioral interventions (increased nocturnal sleep time and daytime napping) and ameliorated daytime sleepiness despite presenting with a slight, but significant, increase of weight

Timing of deformation in the Sarandí del Yí Shear Zone, Uruguay: implications for the amalgamation of western Gondwana during the Neoproterozoic Brasiliano-Pan-African Orogeny

U-Pb and Hf zircon (sensitive high-resolution ion microprobe -SHRIMP- and laser ablation-inductively coupled plasma-mass spectrometry -LA-ICP-MS-), Ar/Ar hornblende and muscovite, and Rb-Sr whole rock-muscovite isochron data from the mylonites of the Sarandí del Yí Shear Zone, Uruguay, were obtained in order to assess the tectonothermal evolution of this crustal-scale structure. Integration of these results with available kinematic, structural, and microstructural data of the shear zone as well as with geochronological data from the adjacent blocks allowed to constrain the onset of deformation along the shear zone at 630-625 Ma during the collision of the Nico Pérez Terrane and the Río de la Plata Craton. The shear zone underwent dextral shearing up to 596 Ma under upper to middle amphibolite facies conditions, which was succeeded by sinistral shearing under lower amphibolite to upper greenschist facies conditions until at least 584 Ma. After emplacement of the Cerro Caperuza granite at 570 Ma, the shear zone underwent only cataclastic deformation between the late Ediacaran and the Cambrian. The Sarandí del Yí Shear Zone is thus related to the syncollisional to postcollisional evolution of the amalgamation of the Río de la Plata Craton and the Nico Pérez Terrane. Furthermore, the obtained data reveal that strain partitioning and localization with time, magmatism emplacement, and fluid circulation are key processes affecting the isotopic systems in mylonitic belts, revealing the complexity in assessing the age of deformation of long-lived shear zone

Heavy Liquid Metal Natural Circulation in a One -Dimensional Loop

ABSTRACT The ENEA Brasimone Research Centre since 1999 is strongly involved in the national and European research programmes performed in the field of heavy liquid metal technology aiming at the development of critical (LFR) and subcritical (ADS) nuclear systems. In particular, in the frame of the IP-EUROTRANS, (6th Framework Program EU), ENEA assumed the commitment to perform an integral experiment with the aim to reproduce the primary flow path of a HLM pool-type nuclear reactor, cooled by Lead Bismuth Eutectics (LBE). This new experimental activity, named ICE "Integral Circulation Experiment", will be performed by an appropriate test section designed to be installed in the CIRCE facility. In order to support the ICE activity, as well as characterise the natural and gas enhanced circulation flow regimes in a HLM loop, qualify test procedures, components nuclear relevant, a new facility was designed and built up by Brasimone Research Centre, named NACIE "NAtural CIrculation Experiment". The paper reports a detailed description of the loop and the main experimental results carried out from the natural circulation tests already performed on the NACIE loop. Numerical simulations have been performed in collaboration with the University of Pisa, adopting the RELAP5/Mod3.3 system code modified to allow for LBE as a cooling fluid. The aim of the performed post-test calculations is to compare the code response with the experimental results under the natural circulation flow regime, allowing to qualify the adopted nodalisation as well as the performance of the code when employed on HLM loop