The path of a scholar

“The path of a scholar” is the introduction to Production, Distribution and Trade: Alternative Perspectives, a volume of essays in honour of Sergio Parrinello (edited by Adriano Birolo, Duncan Foley, Heinz Kurz, Bertram Schefold and Ian Steedman, published by Routledge, 2010). The author traces out the scientific career of Sergio Parrinello in context of the italian market for economists of the sixties and seventies of the twentieth century and critically discusses his most significant works, specially those have resulted as seminal contributions for the later development of the neo-Ricardian theory. This discussion inevitably evolves in a tentative appraisal of the meaning of the neo-Ricardian theory in the recent history of political economy.neo-Ricardian; capital controversy; history of political economy

Effect of Genotype, Gender, and Feed Restriction on Slaughter Results and Meat Quality of Broiler Chickens

Slaughter results and meat quality were evaluated in 768 broilers according to genotype (standard breast yield vs. high breast yield), gender, and feeding systems (ad libitum vs. feed restriction from 13 to 21 d of age). Standard-yield chickens had higher carcass weights (2358 g vs. 2319 g; P < 0.001) and hind legs proportion (31.1% vs. 30.6%; P < 0.01), and lower dressing out percentage (73.6% vs. 74.0%; P < 0.01) compared to high-yield birds, besides lower meat L* index (45.3 vs. 46.2; P < 0.05), higher final pH (5.89 vs. 5.85; P < 0.05) and thawing losses (10.5% vs. 9.43%; P < 0.05). Males showed higher carcass weight (+24%), dressing percentage (+0.7%), and hind leg yield (+4%) (P < 0.001) than females. Restricted birds had lower carcass weight (\u20132%; P < 0.001) and dressing percentage (-0.3%) (P < 0.05) than those always fed ad libitum. As what concerns meat quality, gender and feeding system aff ected only meat final pH, lower in ad libitum group than in restricted one and in females than males. In conclusions, slaughter results and carcass traits changed especially with genotype and gender, coherently with slaughter weight whereas meat quality was mostly affected by genotype

Exploitation of proteomics strategies in protein structure-function studies

Mass spectrometry plays a central role in structural proteomics, particularly in highly intensive structural genomics projects. This review paper reports some examples taken from recent work from the authors' laboratory and is aimed at showing that modem proteomics strategies are instrumental in the integration of structural genomic projects in fields such as: (i) protein-protein interactions, (ii) protein-DNA interactions, (iii) protein-ligand interactions, and (iv) protein-folding intermediates

Interpreting a Classical Geometric Proof with Interactive Realizability.

We show how to extract a monotonic learning algorithm from a classical proof of a geometric statement by interpreting the proof by means of interactive realizability, a realizability sematics for classical logic. The statement is about the existence of a convex angle including a finite collections of points in the real plane and it is related to the existence of a convex hull. We define real numbers as Cauchy sequences of rational numbers, therefore equality and ordering are not decidable. While the proof looks superficially constructive, it employs classical reasoning to handle undecidable comparisons between real numbers, making the underlying algorithm non-effective. The interactive realizability interpretation transforms the non-effective linear algorithm described by the proof into an effective one that uses backtracking to learn from its mistakes. The effective algorithm exhibits a "smart" behavior, performing comparisons only up to the precision required to prove the final statement. This behavior is not explicitly planned but arises from the interactive interpretation of comparisons between Cauchy sequences

The Italian economic research between pluralism and monism: the young economists in the last thirty-year

Taking as good the famous definition of economics attributed to Viner, “Economics is what economists do”, it is surprising to see how little the history of economics has addressed the matter of what economists actually do, above all outside the USA. The vast mass of data on research output which has recently become readily accessible and arrangeable are allowed in this contribution to put into focus (to sharpen) the Italian “representative” economist, at the first rung of the academic ladder, the “Researcher” (ricercatore), in three subsequent periods over last 30 years, 1984 – 2005. With the aim, on the one hand, to trace out the evolution of the scientific profile from the beginning of the 1980s until the end of the period; on the other hand, to verify whether the progressive internationalisation of the profession, the increasing influence of the Anglo-Saxon way of organising research with the introduction of evaluation criteria taking into account the prominence achieved by publications have effectively modified the subjects and methods of research. An extensive database of publications of three cohorts of young economists at the first step of the academic career has been construded. The publications has been classified on the basis of the research structure in economics prevailing at the edge of the 1980s, thus to outline from the inside the evolution of our research model. The outcome: that research model has lost the most part of his pluralistic peculiarities to close in significantly the monistic Anglo-Saxon model. Not a result unexpected; the novelty to emphasize is that the change appeared not step by step but all of a sudden at the transition from the 1980s to the1990s. The publications of the last cohort don’t do anything but conferm that change. Even whitin this metamorphosis, however, the research model that young researchers currently carry out, shows a specificity of the old one: the prominently role, even in the international comparison, of the History of economic analysis that, just about lone, supports the fleg of the pluralism. Other research areas that were typical of and characterized the Italian research model, also in the international research market, such as, for instance, the critical theories (Sraffian and Post-keynesian) coming from the Cambridge (Uk) tradition, have, almost completely, got out from the hunt territory crossed by the young Italian economists; because, perhaps, they are inclined to believe that an academic carrier as economist cannot be developed smoothly if based on research themes outside the nowadays mainstream.Italian research model in economics, evolution, pluralism, monism

Fungal solid state fermentation on agro-industrial wastes for acid wastewater decolourization in a continuous flow packed-bed bioreactor

This study was aimed at developing a process of solid state fermentation (SSF) with the fungi Pleurotus ostreatus and Trametes versicolor on apple processing residues for wastewater decolorization. Both fungi were able to colonize apple residues without any addition of nutrients, material support or water. P. ostreatus produced the highest levels of laccases (up to 9 U g-1 of dry matter) and xylanases (up to 80 U g-1 of dry matter). A repeated batch decolorization experiment was set up with apple residues colonized by P. ostreatus, achieving 50% decolorization and 100% detoxification after 24 h, and, adding fresh wastewater every 24 h, a constant decolorization of 50% was measured for at least 1 month. A continuous decolorization experiment was set up by a packed-bed reactor based on colonized apple residues achieving a performance of 100 mg dye L-1 day-1 at a retention time of 50

Influence of group housing, lactation system and floor type on performance and injuries in rabbit does

To evaluate the effect of group housing, lactation system, and floor type, 40 crossbred multiparous pregnant rabbit does were transferred to individual pens (0.5 m x 1.0 m); 8 does were kept individually during all the trial (I; n=8); the other 32 does were kept in 8 collective pens (2.0 m x 1.0 m, by joining 4 individual pens) in stable groups of 4 individuals (G; n=8) from 8 d until 2 d before kindling and from 2 d until 33 d after kindling. Half pens had wire net floor covered with plastic mats (W; n=8) and the other half plastic slatted floor (P; n=8). Within G does, in half pens (n=4) each doe nursed its own litter (fixed lactation, F); in the remaining half, each doe randomly nursed the litters of the group (random lactation, R). Doe performance at kindling and during lactation, litter performance from standardization until weaning (33 d), and skin injuries on G does (5, 12, 19, 26 and 34 d after kindling) were controlled. The effect of the housing system on performance was tested by PROC GLM of SAS. Within G does, the effect of the lactation system and floor type was evaluated by PROC MIXED (pen as random effect); the injury frequency was analysed by PROC FREQ according to observation day, lactation system, and floor type. Housing system did not affect doe kindling or lactation performance; litter weight at standardization was higher for G than I does (680 vs 619 g, P<0.05), but differences disappeared at weaning. The lactation system showed some residual effects when controlled lactation finished, nests were opened, and kits free of moving. In fact, from 19 to 33 d after kindling, does and litters had higher feed intake (679 g/d vs 602 g/d; P<0.05) and, at 33 d, kits were heavier (775 vs 748 g, P<0.05) in R than in F pens. Floor type (W vs P pens) affected milk production (244 vs 225 g/d; P=0.06), and kit weight at the end of controlled lactation (301 vs 290 g; P<0.05), without residual effects at weaning. The injury frequency changed after the group formation: 34% at 5 d, 47% at 12 d, 13% at 19 and 26 d, and 10% at 34 d of lactation (P<0.05). In conclusion, under our conditions, group housing did not negatively affect doe performance; lactation system and floor type had minor effects; aggressiveness among does was evident after group formation during early lactation but decreased in the late lactation. Further recordings on more reproductive cycles would be necessary to confirm the present results

Effect of stocking density of fish on water quality and growth performance of European Carp and leafy vegetables in a low-tech aquaponic system

Aquaponics (AP) is a semi-closed system of food production that combines aquaculture and hydroponics and represents a new agricultural system integrating producers and consumers. The aim of this study was to test the effect of stocking densities (APL, 2.5 kg m-3; APH, 4.6 kg m-3) on water quality, growth performance of the European Carp (Cyprinus carpio L.), and yield of leafy vegetables (catalogna, lettuce, and Swiss Chard) in a low-technology AP pilot system compared to a hydroponic cultivation. The AP daily consumption of water due to evapotranspiration was not different among treatments with an average value of 8.2 L d-1, equal to 1.37% of the total water content of the system. Dissolved oxygen was significantly (p < 0.05) different among treatments with the lowest median value recorded with the highest stocking density of fish (5.6 mg L-1) and the highest median value in the hydroponic control (8.7 mg L-1). Marketable yield of the vegetables was significantly different among treatments with the highest production in the hydroponic control for catalogna (1.2 kg m-2) and in the APL treatment for Swiss Chard (5.3 kg m-2). The yield of lettuce did not differ significantly between hydroponic control and APL system (4.0 kg m-2 on average). The lowest production of vegetables was obtained in the APH system. The final weight (515 g vs. 413 g for APL and APH, respectively), specific growth rate (0.79% d-1 vs. 0.68% d-1), and feed conversion (1.55 vs. 1.86) of European Carp decreased when stocking density increased, whereas total yield of biomass was higher in the APH system (4.45 kg m-3 vs. 6.88 kg m-3). A low mortality (3% on average) was observed in both AP treatments. Overall, the results showed that a low initial stocking density at 2.5 kg m-3 improved the production of European Carp and of leafy vegetables by maintaining a better water quality in the tested AP system