312 research outputs found
Grasses and legumes in mixture: an energy intercropping system intended for anaerobic digestion
Batch testing of biomethanization was conducted on organic matrices from a mixture of grasses (triticale and barley) and legumes (field bean - Vicia faba L. var . minor ). These tests were performed in mesophylic conditions (35°C) on previously chopped and ensiled biomass. The three crops have been cultivated in Southern Italy (Puglia region), both as single-crops and intercropping between triticale or barley and field bean, in different mixture combinations, during the season 2009-2010. Emphasis was placed on the determination of the chemical composition of feedstock from the three single species and their different intercropping ratios, mowed at two subsequent stages (milk and dough development of grasses), also assessing their consequent biogas and methane potential yields after silage. Seven overall treatments have been compared: the three species in monoculture (triticale, barley and field bean, respectively); two mixtures between triticale and field bean (with triticale at 70 and 50%, respectively); two mixtures between barley and field bean (again with barley at 70 and 50%, respectively). Immediately after cutting and for the next 90 days, biomass samples were closed into plastic mini-silos, each having a 5-L capacity, in order to simulate the silage process. Thereafter, the batch testing was performed and biogas and methane production have been determined, with respect to the main chemical characteristics of the chopped and ensiled biomass samples, able to affect biogas and methane yield. Considering the single-crop treatments the highest biogas per hectare production has been found with respect to triticale (8737.1 nm 3 ha -1 ) and barley (8837.6 nm 3 ha -1 ), at the first and second harvesting stage, respectively. Concerning grass-legume intercropping, the highest biogas yield (8635.0 nm 3 ha -1 ) was observed with reference to the 70:30 mixing ratio, specifically on barley mowed at the milk development stage. The methane content in the biogas ranged from 61.1% (on a 50:50 mixing ratio of barley at the milk stage) to 53.7% (on a barley monoculture at the dough stage)
Role of the irrigation charges to induce the adoption of water saving innovation in semi-arid regions
The paper investigates about the effectiveness of water charges in inducing farmers to adopt the
technical innovation aimed at water saving. It is claimed that by increasing water charge, the signal of
the scarcity of the water resource is directly and effectively conveyed to farmers, who are supposed to
promptly react by adopting a water saving technology. The analysis is referred to two types of innovation:
an agronomic innovation, consisting on a crop mulching practice, and a management
innovation, based on a voluntarily water pricing scheme with tariffs differentiated according to a peak
and off-peak season. A theoretical model based on farms’ profit maximization is proposed, to evaluate
the trigger conditions for the innovation. The model is applied to a case study referred to a semi-arid
region, located in the South of Italy, according to which there is no clear evidence that a generalized
increase may induce farmers to adopt the innovatio
Irrigation pricing policy aimed at the enhancement of water saving innovation at farm level. A case study
In this study we analyze the price inducement effect of a generalized water tariff
increase in the adoption of water saving innovation at farm level. We apply a linear programming
decision making model to analyze the determinants affecting the adoption of two types of innovation:
a process innovation, consisting on a crop mulching practice, and a management innovation, based
on a voluntary water seasonal pricing scheme, differentiated according to a peak and off-peak
periods. According to our results, the mulching practice is not affected by the tariffs that are still lower
than the water marginal productivity, while they exert a negative effect when they become higher. On
the contrary, the adoption of the voluntary water seasonal pricing scheme is affected by the tariffs
increase only if the latter induce an excessive concentration of water demand during the peakDans cette étude nous présentons une recherche relative à la possibilité que
l augmentation de tarif de l eau est capable d induire l agriculteur de adopter une innovation adressée
à l épargne de l eau. Notre modèle de programmation linéaire nous a permis de analyser le procès
de décision de l agriculteur et d entendre les causes déterminantes de l adoption de deux typologies
d innovation: une innovation de procès, relative à une technique de paillis, et une innovation de
management, relative à l introduction d un plan volontaire, avec des tarifs différentes entre les
periodes de intense et de normale utilisation de l eau. Nos résultats montre que l augmentation de
tarif de l eau n est pas une mesure sufficiente pour stimuler les agriculteurs à adopter la technique de
paillis, lorsque le tarif de l eau est inférieur à sa productivité marginale. Ou contraire, quand le tarif est
plus grand que la productivité marginale de l eau, l augmentation de tarif freine l adoption de
l innovation. L introduction des tarifs différentes entre les periodes de intense ed de normale utilisation
de l eau est encouragée par l augmentation de tarif seulement quand la demande de l eau est plus
concentrée dans la la periode de intense utilisation de l ea
Strobilurin Effects on Nitrogen Use Efficiency for the Yield and Protein in Durum Wheat Grown under Rainfed Mediterranean Conditions
In wheat, the increase in nitrogen use efficiency (NUE) and optimization of the nitrogen
doses to be used are both very important aspects for improving sustainable and productive
agriculture. The aim of this study was to investigate, under rainfed Mediterranean conditions, the
influence of strobilurin treatment and N fertilization on durum wheat N use efficiency for yield
(NUEy) and protein (NUEp) and on the contribution of their components, nitrogen uptake efficiency
(UPE) and nitrogen utilization efficiency (NUtE). Two durum wheat cultivars (Saragolla and Sfinge)
were grown for two years in field conditions under five nitrogen treatments (60 kg ha−1 N60; 90 and
120 kg ha−1 given two and three times; N90, N90T3, N120 and N120T3) comparing a control without
strobilurin treatment (ST0) and one application of strobilurin (STaz). In Sfinge, STaz caused a
decrease in UPE and NUEp and an increase in NUtE and NUEy. In Saragolla, the opposite behavior
was observed. Moreover, strobilurin positively affected the contribution of UPE and negatively that
of NUtE to NUEy only in Saragolla. Furthermore, strobilurin determined higher NUEy and NUEp
values under most of the N treatments adopted in the drier year. With this study, we supported the
hypothesis that in Mediterranean conditions, the possibility of reducing N rate application from 120
to 90 kg ha−1 with a strobilurin-based treatment, even in the absence of fungal diseases, could
represent a useful agronomic strategy for durum wheat grown under drought conditions as those
predicted under the ongoing climate change
Forced Response Analysis In a Full-Scale Multistage Centrifugal Compressor: Impeller Vibration Prediction and Validation
Lectur
E-groceries and urban freight: Investigating purchasing habits, peer influence and behaviour change via a discrete choice/agent-based modelling approach
n/
Towards a decision-support procedure to foster stakeholder involvement and acceptability of urban freight transport policies
Purpose: This paper addresses the complex problem of multi-stakeholder decisions in urban freight transport policy-making from a public authority perspective, by proposing a procedure based on a modelling approach to support stakeholder involvement in the decision-making process. The paper analyses the existing methods that can be used for participatory decision-support, with the intent of contextualizing and introducing the innovative modelling approach. Methods: The modelling approach consists of a well-thought integration of discrete choice models (DCM) with agent-based models (ABM) as an effective way to account for stakeholders’ opinions in the policy-making process, while mimicking their interaction to find a shared policy package. The integrated modelling approach is able to combine the advantages of the two methods while overcoming their respective weaknesses. Since it is well grounded on sound microeconomic theory, it provides a detailed (static) stakeholders’ behavioural knowledge, but it is also capable of reproducing agents’ (dynamic) interaction during the decision-making process. The integration allows performing an ex-ante behavioural analysis, with the aim of testing the potential acceptability of the solutions proposed. The methodology is applied in a real case study to prove its feasibility and usefulness for participatory decision-making. Results: The integrated modelling approach can be used for participatory decision-support and it can be casted in the overall UFT policy-making process. The results of the behavioural analysis, in terms of ranking of potentially accepted policies, linked with the technical evaluations from transport network modelling tools, provide a sound basis for active participation and deliberation with stakeholders and policy-makers. The aim is to guide an effective participation process aimed at consensus building among stakeholders, by proposing them a subset of policies that, as a result of a preliminary analysis, are likely to be accepted while performing well in terms of technical results. Conclusions: This approach, integrating DCM and ABM, represents a promising way to tackle the complexity of multi-stakeholder involvement in UFT policy-making and to support an efficient and effective decision-making process. It produces an added value for UFT policy-making and it can be framed in the overall context of transport planning. In fact, together with technical and economic analyses, the stakeholder behavioural analysis proposed contributes to the ex-ante policy assessment needed to support decision-makers in taking well-thought decisions. Keywords: stakeholder behavioural analysis, discrete choice models, agent-based models, city logistics, participatory policy-makingpublishedVersio
2D Video Analysis System to Analyze the Performance Model of Figure Roller Skating: A Pilot Study
Figure roller skating is a discipline composed of various movements which involve jumps,
artistic figures and spins in a seamless program which has both technical and shapely difficult. A
biomechanical analysis of a double salchow was performed using a 2D video analysis of one
European and in two Italian roller skaters. On average, the high level (HL) roller skater showed a
horizontal velocity of the center of mass higher than the average, especially in the prop stage,
whereas the medium level (ML) and low level (LL) athletes reduced their velocity significantly. The
spin angular velocity of the ML and LL skaters was always higher than of the HL. This phenomenon
would seem to be a compensatory strategy for a lower jump height, with a reduced trunk-thigh
angle and less thigh lever arm (coxo-femur/knee joints) during the take-off and landing phases of
the double salchow jump
CXCL12 prolongs naive CD4 + T lymphocytes survival via activation of PKA, CREB and Bcl2 and BclXl up-regulation
Naive T lymphocytes recirculate through the body, traveling from secondary lymphoid organs through tissues and via lymphatic vessels and peripheral blood into other secondary lymphoid organs and into the bone marrow. In these tissues, lymphocytes are exposed to the chemokine CXCL12 which is abundantly produced in bone marrow and in lymph nodes by stromal cells. CXCL12 is known to drive lymphocytes chemotaxis and, in cells types such as stem cells, an antiapopototic effect has been described. Methods Here we analyzed the effect of CXCL12 exposure on naïve CD4 + T lymphocytes purified from peripheral blood by immunomagnetic negative isolation and cultured in a nutrient poor medium. We also studied, mainly by western blot analysis, the signaling pathways involved in CXCL12 action on naïve CD4 + T lymphocytes. Results We found that CXCL12-exposed cells survived longer than untreated ones and this prolonged lifespan was specific for resting naïve lymphocytes, while in vitro activated lymphoblasts died rapidly despite CXCL12 treatment. We demonstrated that the increased percentage of living cells observed upon CXCL12 administration was not due to induction of proliferation but to a prosurvival effect of this chemokine. Moreover, our data suggest that this prosurvival effect on naïve CD4 + T lymphocytes might likely be mediated by PKA-dependent CREB activation and consequent increased expression of the antiapoptotic factors Bcl2 and BclXl. Conclusions This newly reported activity of CXCL12 might contribute to the maintenance of the naïve T lymphocytes pool in vivo, which is needed to ensure a proper immune response to new antigens
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