This paper investigates the co-evolution of the CAP expenditure and of the farms’ performance and choices to assess whether and to what extent CAP assessment itself meets the requisites of Causal ...Inference. In order to identify some regularities in this co-evolution, the analysis is performed on a constant group of professional farms over a long enough time period. The Italian 2008-2019 FADN balanced sample is here considered. Results points to two major empirical implications. First of all, they question whether CAP expenditure is actually accompanied by any significant farmers’ response. An exception may actually concern the support specifically focused on environmental standards. Secondly, they raises some major methodological issues about the applicability of the Treatment Effect logic to CAP assessment.
This paper investigates the occurrence of common price shocks (co-exceedance) across different commodities. IMF monthly price series of 11 commodities are considered over the 1980-2021 period. The ...analysis considers two alternative stochastic processes. The first looks for common volatility clusters using individual GARCH models to detect whether and when respective clusters overlap. Through an appropriate battery of tests, the second alternative looks for a common Bubble Generating Process (BGP) by searching for individual explosive roots and then dating them to identify the possible overlaps and first movers. Evidence emerging about these shock generating processes is linked to the analogous behaviour of the US Consumer Price Index (CPI) to assess to what extent inflation shocks can be associated to the observed commodity price spikes. Results show that the detection of temporary bubbles and volatility clusters only partially agrees on the episodes of exuberance, on the first-moving commodities and on the involvement of the CPI. This provides helpful suggestions on the development of a real-time surveillance tool supporting policy intervention in periods of commodity price turbulence.
This article analyzes long-term agricultural Total Factor Productivity (TFP) growth at regional level by testing its time-series properties and identifying factors associated with divergence as ...opposed to convergence. The empirical application concerns Italian regions over the 1951-2002 time period. TFP growth decomposition ultimately attributes the observed productivity growth performance to these contrasting (convergence vs. divergence) forces. We find that technological spillovers are the key convergence force regardless of how the spillover effects are computed. At the same time, forces favoring convergence are almost offset by divergence forces (mainly scale or learning effects). This decomposition may explain the persistence of TFP growth rate differences in Italian agriculture, and could be applicable elsewhere.
Electrically interfacing the skin for monitoring personal health condition is the basis of skin‐contact electrophysiology. In the clinical practice the use of stiff and bulky pregelled or dry ...electrodes, in contrast to the soft body tissues, imposes severe restrictions to user comfort and mobility while limiting clinical applications. Here, in this work dry, unperceivable temporary tattoo electrodes are presented. Customized single or multielectrode arrays are readily fabricated by inkjet printing of conducting polymer onto commercial decal transfer paper, which allows for easy transfer on the user's skin. Conformal adhesion to the skin is provided thanks to their ultralow thickness (<1 µm). Tattoo electrode–skin contact impedance is characterized on short‐ (1 h) and long‐term (48 h) and compared with standard pregelled and dry electrodes. The viability in electrophysiology is validated by surface electromyography and electrocardiography recordings on various locations on limbs and face. A novel concept of tattoo as perforable skin‐contact electrode, through which hairs can grow, is demonstrated, thus permitting to envision very long‐term recordings on areas with high hair density. The proposed materials and patterning strategy make this technology amenable for large‐scale production of low‐cost sensing devices.
Temporary tattoo electrodes are fabricated by inkjet printing and tested as unperceivable skin‐contact electrodes in various electrophysiology applications. Ultralow thickness (<1 µm) endows tattoos with conformable adhesion to skin and capability to be perforated by growing hairs. Custom multielectrodes arrays can be designed in view of specific applications in diagnostics, human machine interfacing, and personal health monitoring.
This paper investigates the non-monetary motivations of farmers' adoption of agri-environmental policies. Unlike the monetary (income) motivations, non-monetary drivers can not be directly observed ...but can be identified from observational data within appropriate quasi-experimental designs. A theoretical justification of farmers' choices is first formulated and a consequent natural experiment setting is derived. The latter admits heterogeneous, i.e. Individual, Treatment Effects (ITE) that, in turn, can be interpreted in terms of more targeted and tailored policy expenditure. A Causal Forest (CF) approach is adopted to estimate these ITEs for both the treated and not treated units. The approach is applied to two balanced panel samples of Italian Farm Accountancy Data Network (FADN) farms observed over the 2008–2018 period and concerns agri-environmental policies delivered through the Common Agricultural Policy (CAP). Results show how heterogeneous the farmers’ response and the associated non-monetary motivations can be, thus indicating room for a more efficient policy design.
•Existence and relevance of non-monetary motivations in environmental adoption is investigated.•A theoretical justification of farmers' choices is formulated and a consequent natural experiment setting derived.•A Causal Forest approach is adopted to estimate the Individual Treatment Effects.•The approach is applied to two balanced panel samples of Italian farms over the 2008–2018 period.•Results indicate room for a more efficient policy design in this field.
This article investigates the impact of both the Common Agricultural Policy and structural policies on European regions by estimating a conditional growth convergence model. The Common Agricultural ...Policy influences the convergence process by affecting regional aggregate productivity, eventually conflicting with the structural policies designed to promote growth in lagging regions. The conditional convergence model is specified in a dynamic panel data form and applied to 206 regions observed from 1989 to 2000. A GMM estimation is applied in order to obtain consistent estimates of both the convergence parameter β and the impact of the conditioning variables, policy measures in particular.
•tDCS was used for interfering with the central pathways governing intra-limb APAs.•SMA was stimulated in anodal, cathodal and sham configuration during finger tapping.•Anodal tDCS increased APAs in ...biceps and triceps, muscle that stabilize the elbow.•tDCS had no effect on prime mover recruitment and voluntary movement kinematics.•The postural and the voluntary commands seem already separated before entering SMA
Recent works provide evidences that anticipatory postural adjustments (APAs) are programmed with the prime mover recruitment as a shared posturo-focal command. However the ability of the CNS to adjust APAs to changes in the postural context implies that the postural and voluntary components should take different pathways before reaching the representation of single muscles in the primary motor cortex. Here we test if such bifurcation takes place at the level of the supplementary motor area (SMA).
TDCS was applied over the SMA in 14 subjects, who produced a brisk index-finger flexion. This activity is preceded by inhibitory APAs, carved in the tonic activity of Biceps Brachii and Anterior Deltoid, and by an excitatory APA in Triceps Brachii. Subjects performed a series of 30 flexions before, during and after 20min of tDCS in CATHODAL, ANODAL or SHAM configuration.
The inhibitory APA in Biceps and the excitatory APA in Triceps were both greater in ANODAL than in SHAM and CATHODAL configurations, while no difference was found among the latter two (ANODAL vs. SHAM: biceps +26.5%, triceps +66%; ANODAL vs. CATHODAL: biceps +20.5%, triceps: +63.4%; for both muscles, ANOVA p<0.02, Tukey p<0.05). Instead, the APA in anterior deltoid was unchanged in all configurations. No changes were observed in prime mover recruitment and index-finger kinematics.
Results show that the SMA is involved in modulating APAs amplitude. Moreover, the differential effect of tDCS observed on postural and voluntary commands suggests that these two components of the motor program are already separated before entering SMA.
Anticipatory Postural Adjustments (APAs) are commonly described as unconscious muscular activities aimed to counterbalance the perturbation caused by the primary movement, so as to ensure the ...whole-body balance, as well as contributing to initiate the displacement of the body center of mass when starting gait or whole-body reaching movements. These activities usually create one or more fixation chains which spread over several muscles of different limbs, and may be thus called
. However, it has been reported that APAs also precede voluntary movements involving tiny masses, like a flexion/extension of the wrist or even a brisk flexion of the index-finger. In particular, such movements are preceded by an
APA chain, that involves muscles acting on the proximal joints. Considering the small mass of the moving segments, it is unlikely that the ensuing perturbation could threaten the whole-body balance, so that it is interesting to enquire the physiological role of
APAs and their organization and control compared to
APAs. This review is focused on
APAs and highlights a strict correspondence in their behavior and temporal/spatial organization with respect to
APAs. Hence it is suggested that both are manifestations of the same phenomenon. Particular emphasis is given to
APAs preceding index-finger flexion, because their relatively simple biomechanics and the fact that muscular actions were limited to a single arm allowed peculiar investigations, leading to important conclusions. Indeed, such paradigm provided evidence that by granting a proper fixation of those body segments proximal to the moving one APAs are involved in refining movement precision, and also that APAs and prime mover activation are driven by a shared motor command.
The paper presents an evolutionary perspective on how Agricultural Knowledge and Innovation Systems (AKIS) have adapted over time to new challenges and technological paradigm and trajectories. ...Starting from a conventional science-based approach and the robust empirical evidence supporting it, the analysis highlights the emergence of some system failures and the need for new conceptualization and design of the AKIS. Particularly concentrating on developed countries’ agenda, we then discuss how, along this evolutionary pattern, bioeconomy emerges as the convergence of traditional sectors as a result of these new technological trajectories. Finally, some implications for the EU policies are drawn.
Anticipatory postural adjustments (APAs) are the coordinated muscular activities that precede the voluntary movements to counteract the associated postural perturbations. Many studies about gait ...initiation call APAs those activities that precede the heel-off of the leading foot, thus taking heel-off as the onset of voluntary movement. In particular, leg muscles drive the center of pressure (CoP) both laterally, to shift the body weight over the trailing foot and backward, to create a disequilibrium torque pushing forward the center of mass (CoM). However, since subjects want to propel their body rather than lift their foot, the onset of gait should be the CoM displacement, which starts with the backward CoP shift. If so, the leg muscles driving such a shift are the prime movers. Moreover, since the disequilibrium torque is mechanically equivalent to a forward force acting at the pelvis level, APAs should be required to link the body segments to the pelvis: distributing such concentrated force throughout the body would make all segments move homogeneously. In the aim of testing this hypothesis, we analyzed gait initiation in 15 right-footed healthy subjects, searching for activities in trunk muscles that precede the onset of the backward CoP shift. Subjects stood on a force plate for about 10 s and then started walking at their natural speed. A minimum of 10 trials were collected. A force plate measured the CoP position while wireless probes recorded the electromyographic activities. Recordings ascertained that at gait onset APAs develop in trunk muscles. On the right side, Rectus Abdominis and Obliquus Abdominis were activated in 11 and 13 subjects, respectively, starting on average 33 and 54 ms before the CoP shift; Erector Spinae (ES) at L2 and T3 levels was instead inhibited (9 and 7 subjects, 104 and 120 ms). On the contralateral side, the same muscles showed excitatory APAs (abdominals in 11 and 12 subjects, 27 and 82 ms; ES in 10 and 7 subjects, 75 and 32 ms). The results of this study provide a novel framework for distinguishing postural from voluntary actions, which may be relevant for the diagnosis and rehabilitation of gait disorders.
PDF
