Groundwater-dependent ecosystems as transfer vectors of nitrogen from the aquifer to surface waters in agricultural basins: The fontanili of the Po Plain (Italy).

The most spread groundwater-dependent ecosystems in the River Po valley are semi-natural lowland springs called "fontanili". They provide specific habitats and support high biodiversity, but are often strongly impaired by agricultural pollution. In the present study we seasonally monitored the discharge and nitrogen concentration of 48 fontanili from the Adda and the Ticino river basins. We observed a wide spatial variability of both NO3-N concentrations and flows. The annual NO3-N loads ranged from <1 to 75 t y-1 and < 1 to 29 t y-1 in the Adda and Ticino basins respectively. In the springs characterized by variable discharge the N loads were exported mostly during the summer season when water table level was elevated mainly due to irrigation. Upscaling the mean NO3-N load to each river catchment based on the total number of springs, we obtained an aerial export of 33.2 ± 6.0 and 12.5 ± 3.2 kg y-1 ha-1. Such loads accounted for the 30.4 and 21.5% of the N surplus estimated for the Adda and Ticino basins respectively. Random Forest analysis was performed to identify the most important environmental variables influencing the nitrate contamination in the spring waters. A total of 22 explanatory variables related to N sources, land uses, intrinsic hydrogeologic and soil proprieties, in "situ" and remotely sensed variables were considered. The percent of soil cultivated with maize in a 500 m radius buffer area surrounding the sampling site, the N from manure and the distance of each spring from the main river were the most effective factors in controlling the NO3-N concentration in the fontanili water. The outcomes of this work open up to achievable management prospects for the protection and recovery of fontanili waters, and can be particularly useful for water managers in identifying areas and sites where restoration plans should be a priority.

Improving proprioceptive deficits after stroke through robot-assisted training of the upper limb: a pilot case report study.

The purpose of this study was to determine whether a conventional robot-assisted therapy of the upper limb was able to improve proprioception and motor recovery of an individual after stroke who exhibited proprioceptive deficits. After robotic sensorimotor training, significant changes were observed in kinematic performance variables. Two quantitative parameters evaluating position sense improved after training. Range of motion during shoulder and wrist flexion improved, but only wrist flexion remained improved at 3-month follow-up. These preliminary results suggest that intensive robot-aided rehabilitation may play an important role in the recovery of sensory function. However, further studies are required to confirm these data.

Evaluation of upper limb sense of position in healthy individuals and patients after stroke.

The aims of this study were to develop and evaluate reliability of a quantitative assessment tool for upper limb sense of position on the horizontal plane. We evaluated 15 healthy individuals (controls) and 9 stroke patients. A robotic device passively moved one arm of the blindfolded participant who had to actively move his/her opposite hand to the mirror location in the workspace. Upper-limb's position was evaluated by a digital camera. The position of the passive hand was compared with the active hand's 'mirror' position. Performance metrics were then computed to measure the mean absolute errors, error variability, spatial contraction/expansion, and systematic shifts. No significant differences were observed between dominant and non-dominant active arms of controls. All performance parameters of the post-stroke group differed significantly from those of controls. This tool can provide a quantitative measure of upper limb sense of position, therefore allowing detection of changes due to rehabilitation.

Nitrogen inputs to a river course in a heavily impacted watershed: a combined hydrochemical and isotopic evaluation (Oglio River Basin, N Italy).

This study aims at evaluating sources and processes affecting NO3(-) concentrations in the Oglio River. Five sampling campaigns considered the main watercourse, tributaries, point pollution sources, springs, and groundwater. Physico-chemical parameters, N forms, B, Sr(2+), stable isotopes (δ(2)HH2O, δ(18)OH2O, δ(15)NNO3, δ(18)ONO3, δ(11)B) and discharge were measured. Hydrological modelling was performed using mass balance and End Member Mixing Analysis equations. During the irrigation period, in the upstream reach, up to 90% of the natural river flow is diverted for irrigation and industrial purposes; excess water drained from agricultural fields is returned to river in the downstream reach. Results evidenced, in the middle reach, a large input of NO3(-)-rich groundwater which could be quantified using hydrological modelling. Groundwater inputs are responsible for the sharp, tenfold increase in NO3(-) in the river water, from 2.2-4.4 up to 33.5 mgL(-1), and are more evident in summer, when discharge is lower. Nevertheless, river water preserves its natural B isotopic composition, indicating that the two tracers do not have a common origin and are not co-migrant. In the lower plain, surface-groundwater interconnections and human disturbances in the water cycle favour the recycling of the compounds in the environment, and lead to a similarity in composition of the different water bodies (Oglio River, tributaries and groundwater). The long lasting agronomical practices have profoundly modified the surface-groundwater equilibrium and chemical characteristics, resulting in a highly buffered system. Infiltrating irrigation water leaches down NO3(-) which is subsequently denitrified; when returned to the Oglio River, groundwater modifies the river water composition by dilution, in the case of NO3(-), or by addition, for other constituents (e.g. Cl(-), B). The results of this study indicate that, in order to reduce the NO3(-) transport towards the Adriatic Sea, groundwater contamination should be addressed first, with expected long recovery times.

Robot-aided neurorehabilitation in sub-acute and chronic stroke: does spontaneous recovery have a limited impact on outcome?

BACKGROUND: Robotic neurorehabilitation, thanks to high dosage/intensity training protocols, has the potential for a greater impact on impairment. OBJECTIVE: We aimed to analyze how time since the acute event may influence the motor recovery process during robot-assisted rehabilitation of the upper limb. METHODS: A total of 41 patients after stroke were enrolled: 20 in subacute phase, i.e. ≤ 6 months elapsed since their unilateral cerebrovascular accident (CVA), and 21 at chronic stage, i.e. > 6 months since CVA. All subjects underwent 30 minutes of robot-aided rehabilitation twice a day, 5 days a week for at least three weeks of training. Patients were evaluated at the start and end of treatment using the Fugl-Meyer and Modified Ashworth clinical scales and by a set of robot measured kinematic parameters. The time interval from stroke was considered as a grouping factor to analyze its impact on time course of recovery. RESULTS: After training both groups significantly improved their impairment (F = 44.25, p < 0.001) but sub-acute patients showed a greater improvement on the Fugl-Meyer scale than chronic patients. The time course of recovery of the kinematic variables showed higher time constants of motor improvement in the sub-acute than chronic group, but they were one order lower than spontaneous recovery time constants. CONCLUSIONS: Spontaneous recovery seems to have a limited impact on the improvement of sub-acute patients, most of their changes being likely due to re-learning during rehabilitation. In addition, a longer recovery time was required to maximize outcome in sub-acute than in chronic patients.

Modeling upper limb clinical scales by robot-measured performance parameters.

The status of motor function in stroke survivors and the effect of any therapeutic intervention are generally measured by physiotherapists using clinical assessment scales that probe specific aspects of a subject's motor behavior. Although they are widely accepted, these measurement tools are limited by interrater and intrarater reliability and are time-consuming to apply. This paper analyzes the changes in movement kinematics and kinetics during robot-aided neurorehabilitation of subjects after stroke and verifies the possibility of estimating outcome measures by means of a set of robot measured parameters.

Development of a progressive task regulation algorithm for robot-aided rehabilitation.

Patient motivation is an important factor in rehabilitation. The difficulty level of the motor task, the awareness of the performance obtained, and the quantity and quality of feedbacks presented to the patient can influence patient motivation and produce different ways of acting and different performances. This study presents a Progressive Task Regulation algorithm able to evaluate the patient's performance during training and automatically change the features of the reaching movement, so as to adapt automatically the difficulty level of the motor task to the patient's ability. Use of the progressive task regulation algorithm should promote patient motivation throughout the course of treatment.

Assessing mechanisms of recovery during robot-aided neurorehabilitation of the upper limb.

OBJECTIVE: The present study aimed to qualify and quantify the different components of motor recovery in a group of stroke patients treated by robot-aided techniques. In addition, the learning model of each motor recovery component was analyzed. METHODS: Two groups of poststroke patients were treated with the use of an elbow-shoulder manipulator, respectively, within (recent) and after (chronic) the first 6 months of their cerebrovascular accident. Both groups were evaluated by means of standard clinical assessment scales and a robot-measured evaluation method. RESULTS: These findings confirm that motor training consisting of voluntary movements assisted by the robot device led to significant improvements in motor performance in terms of the kinematic and dynamic components of the arm movements. This corresponded to improvement of impairment as confirmed by the clinical scale results. CONCLUSIONS: Knowledge of the recovery components and of the associated performance acquisition model may be useful in assessing and training stroke patients and should make it possible to precisely plan and, if necessary, modify the rehabilitation strategies.