Coase theorem and exchangeable rights in non-cooperative games

In this paper, we consider the Coase theorem in a non cooperative game framework. In particular, we explore the robustness of the Coase theorem with respect to the ?nal distribution of alienable property rights which constitutes, as far as we know, a less cultivated ?eld of research. In our framework, in order to reach e¢ ciency, agents have to stipulate binding contracts. In the analysis, we distinguish between permanent and temporary contracts showing the di¤erent implication of the two kinds of contracts with respect to the ?nal attribution of individual rights. More precisely, we show that, with temporary binding contracts and under particular assumptions, the ?nal attribution if individual rights does not converge.Coase theorem, binding contracts, side payments

Extra-articular tenodesis combined with an anterior cruciate ligament reconstruction in acute anterior cruciate ligament tear in elite female football players

PURPOSE: The growing popularity of elite soccer among female participants has led to increased incidents of anterior cruciate ligament (ACL) ruptures. Many authors underline a positive glide after ACL reconstruction (ACLR), especially in women. In fact, an isolated intra-articular ACLR may be inadequate to control rotational instability after a combined injury of the ACL and the peripheral structures of the knee. Extra-articular procedures are sometimes used in primary cases displaying excessive antero-lateral rotatory instability. The purpose of this case series was to report subjective and objective outcomes after combined ACL and lateral extra-articular tenodesis (LET) with a minimum 4-year follow-up in a selected high-risk population of elite female football players. METHODS: Between January 2007 and December 2010, 16 elite Italian female football players were included in the study. All patients underwent the same surgical technique: anatomical ACLR with autogenous semitendinosus and gracilis tendons. After the intra-articular reconstruction was performed, an additional extra-articular MacIntosh modified Coker-Arnold procedure was carried out. Patients were assessed pre- and post-operatively with the subjective and objective International Knee Documentation Committee (IKDC) evaluation form, Tegner activity scale (TAS) and Lysholm score. Joint laxity was assessed with KT-1000 by measuring the side-to-side (S/S) differences in displacement at manual maximum (mm) testing. RESULTS: At a mean follow-up of 72.6 ± 8.1 months, two independent examiners reviewed all players. All of the patients had a fully recovered range of motion. Lachman test was negative in all patients (100 %). The evaluation of joint laxity and clinical evaluation showed a statistically significant improvement. No patients experienced complication or a re-rupture. DISCUSSION: The rationale of combining extra-articular procedures with ACLR is to restrict the internal rotation of the reconstructed knee, taking advantage of its long lever arm and thus providing more stability in the rotational axis and preventing the ACL graft from undergoing further excessive strain. CONCLUSIONS: The combination of an LET with ACLR in elite female football players demonstrated excellent results in terms of subjective scales, post-operative residual laxity and re-rupture rate with no complication, and a complete return to sport activity

Evaluation of the accuracy of a patient-specific instrumentation

Patient-specific instruments (PSI) has been introduced with the aim to reduce the overall costs of the implants, minimizing the size and number of instruments required, and also reducing surgery time. The aim of this study was to perform a review of the current literature, as well as to report about our personal experience, to assess reliability and accuracy of patient specific instrument system in total knee arthroplasty (TKA). A literature review was conducted of PSI system reviewing articles related to coronal alignment, clinical knee and function scores, cost, patient satisfaction and complications. Studies have reported incidences of coronal alignment ≥3° from neutral in TKAs performed with patient-specific cutting guides ranging from 6% to 31%. PSI seem not to be able to result in the same degree of accuracy as for the CAS system, while comparing well with standard manual technique with respect to component positioning and overall lower axis, in particular in the sagittal plane. In cases in which custom-made cutting jigs were used, we recommend performing an accurate control of the alignment before and after any cuts and in any further step of the procedure, in order to avoid possible outliers

Can the outside-in half-tunnel technique reduce femoral tunnel widening in anterior cruciate ligament reconstruction? A CT study

There are different techniques for drilling the femoral tunnel in the anterior cruciate ligament reconstruction (ACLR), but their influence in the bone tunnel enlargement in unknown. The purpose of this study was to compare two different surgical techniques for evaluating femoral tunnel enlargement in ACLR. The hypothesis was that tunnel placement using the outside-in technique leads to less tunnel enlargement compared to the transtibial technique. METHODS: Forty-four patients treated for ACLR between March 2013 and March 2014 were prospectively enrolled in this study. According to the surgical technique, subjects were assigned to Group A (Out-in) or Group B (Transtibial). All patients underwent CT examination in order to evaluate the femoral tunnel enlargement at four different levels. Moreover, all patients were evaluated with the Lachman test and pivot shift test, and the KT1000 arthrometer was used to measure the anterior laxity of the knee. A subjective evaluation was performed using the 2000 International Knee Documentation Committee Subjective Knee score, Lysholm knee score and Tegner activity scale. All patients were assessed after 24 months of follow-up. RESULTS: At the final follow-up, there were statistically significant differences (p 0.05). CONCLUSIONS: In ACLR with a suspension system, the outside-in technique leads to less enlargement of the femoral tunnel lower than the transtibial technique. KEYWORDS: Anterior cruciate ligament reconstruction; CT imaging; Drilling technique; Femoral tunnel enlargement PMID: 28389757 DOI: 10.1007/s00590-017-1950-8 Share on FacebookShare on TwitterShare on Google+ LinkOut - more resource

Risultati clinico-strumentali del trattamento dell'artrosi trapezio-metacarpale mediante artroplastica di interposizone

Introduzione: La rizoartrosi (artrosi trapezio-metacarpale) rappresenta il 10% delle localizzazioni artrosiche di tutto il corpo. L’ artroplastica di interposizione secondo Robinson prevede l’esecuzione di trapeziectomia ed innesto tendineo con emi Abduttore Lungo del Pollice (APL) inserito nel gap creato dalla trapeziectomia. Lo scopo dello studio è quello di valutare i risultati clinici e strumentali dell’artroplastica di interposizione ad un follow-up di medio-lungo termine valutando mediante studio RMN l’evoluzione del innesto, ed una sua eventuale associazione con gli risultati clinici. Materiali e Metodi: Da Luglio 2006 a Maggio 2012, sono stati trattati chirurgicamente 75 pazienti affetti da rizoartrosi.64 pazienti rientravano nei criteri di inclusione dello studio. La valutazione clinica è stata effettuata mediante Grind test, Kapandji test, DASH score, VAS score, valutazione della ROM in abduzione radiale, e soddisfazione soggettiva del paziente. L’esame strumentale è stato effettuato mediante RX in antero-posteriore e laterale, sono state inoltre analizzate sequenze T1-, T2-, STIR-, Spin Echo e Gradient Echo-MRI alla RMN. Risultati: 44 pazienti (68.75%) sono risultati pienamente soddisfatti, 16 pazienti (25%) hanno riportato grande beneficio e hanno ripreso tutte le attività quotidiane con limitazione minima. Solo 4 pazienti (6.25%) non sono stati soddisfatti dell’intervento. La distanza scafo-metacarpale (SMD) valutata radiograficamente nel 1 mese post operatorio ha mostrato un valore medio di 6.6±1.7SD mm. All’ultimo follow-up il valore medio (SMD) è risultato essere di 4.3±1.2SD mm, con una migrazione prossimale media di 2.3±0.9SD mm. La valutazione con RMN ha mostrato nel 100% dei pazienti la presenza di tessuto fibroso residuo nello spazio tra la base del primo metacarpo e lo scafoide. Nel 37.5% dei pazienti è stata osservata la presenza di edema osseo subcondrale. Il 50% dei pazienti mostravano sinovite reattiva alla RMN. Discussione/Conclusioni: L’artroplastica di interposizione è un trattamento sicuro e validato per il trattamento dei pazienti affetti da rizoartrosi di stadio III-IV secondo Eaton-Littler che garantisce buoni risultati clinici ed il ritorno alle normali attività di vita quotidiana. La quantità di tessuto fibroso residuo interposto dopo la trapeziectomia sembra essere correlate a migliori risultati clinico / radiografici e maggiore soddisfazione da parte dei pazienti

Segond's fracture: a biomechanical cadaveric study using navigation

Background Segond’s fracture is a well-recognised radiological sign of an anterior cruciate ligament (ACL) tear. While previous studies evaluated the role of the anterolateral ligament (ALL) and complex injuries on rotational stability of the knee, there are no studies on the biomechanical effect of Segond’s fracture in an ACL deficient knee. The aim of this study was to evaluate the effect of a Segond’s fracture on knee rotation stability as evaluated by a navigation system in an ACL deficient knee. Materials and methods Three different conditions were tested on seven knee specimens: intact knee, ACL deficient knee and ACL deficient knee with Segond’s fracture. Static and dynamic measurements of anterior tibial translation (ATT) and axial tibial rotation (ATR) were recorded by the navigation system (2.2 OrthoPilot ACL navigation system B. Braun Aesculap, Tuttlingen, Germany). Results Static measurements at 30 showed that the mean ATT at 30 of knee flexion was 5.1 ± 2.7 mm in the ACL intact condition, 14.3 ± 3.1 mm after ACL cut (P = 0.005), and 15.2 ± 3.6 mm after Segond’s fracture (P = 0.08). The mean ATR at 30 of knee flexion was 20.7 ± 4.8 in the ACL intact condition, 26.9 ± 4.1 in the ACL deficient knee (P[0.05) and 30.9 ± 3.8 after Segond’s fracture (P = 0.005). Dynamic measurements during the pivot-shift showed that the mean ATT was 7.2 ± 2.7 mm in the intact knee, 9.1 ± 3.3 mm in the ACL deficient knee(P = 0.04) and 9.7 ± 4.3 mm in the ACL deficient knee with Segond’s fracture (P = 0.07). The mean ATR was 9.6 ± 1.8 in the intact knee, 12.3 ± 2.3 in the ACL deficient knee (P[0.05) and 19.1 ± 3.1 in the ACL deficient knee with Segond’s lesion (P = 0.016). Conclusion An isolated lesion of the ACL only affects ATT during static and dynamic measurements, while the addition of Segond’s fracture has a significant effect on ATR in both static and dynamic execution of the pivot-shift test, as evaluated with the aid of navigation

The future of sovereignty in multilevel governance Europe: a constructivist reading

Multilevel governance presents a depiction of contemporary structures in EU Europe as consisting of overlapping authorities and competing competencies. By focusing on emerging non-anarchical structures in the international system, hence moving beyond the conventional hierarchy/anarchy dichotomy to distinguish domestic and international arenas, this seems a radical transformation of the familiar Westphalian system and to undermine state sovereignty. Paradoxically, however, the principle of sovereignty proves to be resilient despite its alleged empirical decline. This article argues that social constructivism can explain the paradox, by considering sovereign statehood as a process-dependent institutional fact, and by showing that multilevel governance can feed into this process

En memoria de Francisco Javier Peñas Esteban

Títulos y autores de las dedicatorias. - ¡Querido amigo! Compañero de pasiones y sueños. María José BECERRA y Diego BUFFA - Paco Peñas y el giro culturalista de la izquierda. Alicia CAMPOS SERRANO - Preservando el momento humano (en memoria de Francisco Javier Peñas). Stefano GUZZINI - Francisco Javier Peñas Esteban post mortem: el honor de pensar o una permanente mirada crítica. Mbuyi KABUNDA - Francisco Javier Peñas Esteban. Gladys LECHINI - Conversaciones entre dos hombres buenos. Irene MARTÍN - Paco, el director de tesis padre académico. Alice MARTINI - Paco Peñas, un internacionalista ejemplar. Jaime PASTOR - Erudición con causa. Un legado ético y político. Karlos PÉREZ DE ARMIÑ

What is the Other of Europe?

Peer reviewe

Analysis of the existing barriers for the market development of power to hydrogen (P2H) in Italy

New technological solutions are required to control the impact of the increasing presence of renewable energy sources connected to the electric grid that are characterized by unpredictable production (i.e., wind and solar energy). Energy storage is becoming essential to stabilize the grid when a mismatch between production and demand occurs. Among the available solutions, Power to Hydrogen (P2H) is one of the most attractive options. However, despite the potential, many barriers currently hinder P2H market development. The literature reports general barriers and strategies to overcome them, but a specific analysis is fundamental to identifying how these barriers concretely arise in national and regional frameworks, since tailored solutions are needed to foster the development of P2H local market. The paper aims to identify and to analyze the existing barriers for P2H market uptake in Italy. The paper shows how several technical, regulatory and economic issues are still unsolved, resulting in a source of uncertainty for P2H investment. The paper also suggests possible approaches and solutions to address the Italian barriers and to support politics and decision-makers in the definition and implementation of the national hydrogen strategy