Swords and Plowshares: Regional Trade Agreements and Political Conflict in Africa

The end of the Cold War and the apparent stability of the contemporary international system, in which the probability of a major war is at its lowest for centuries, have spurred a lively debate on the causes of peace. One of the most popular explanations is based on the classic liberal statement that economic interdependence reduces political conflict. Globalisation, narrowly defined as the increase in the quantity and quality of international economic exchanges experienced in the last few years, would then be one of the main reasons for international political stability. Even at the regional level, therefore, the increase in economic intercourse should bring, as a welcome political externality, the amelioration of international conflict. This view posits, for instance, that the emergence of a «zone of peace» within Western Europe has been brought about by the creation of a common market which has created a powerful incentive to avoid political conflict. Or that in other areas, such as Latin America, the recent increase in regional stability would rest on the launch of Mercosur and the greater interdependence that it has brought about. The hypothesis is that Regional Trade Agreements (RTAs) facilitate economic interdependence, which in turn facilitate political stability. In this paper we apply this hypothesis to the African case where a significant number of RTAs has been created in the last decades. Expectations of increased political stability have not, however, been confirmed. This does not necessarily undermine the general proposition of a positive correlation between interdependence and peace, but it does suggest that the relationship between the two elements may be more complicated than often acknowledged. On the one hand, African RTAs may simply not have produced the necessary level of trade and investment for a significant modification of political preferences. On the other hand, interdependence may be a necessary condition for peace, but it may also be insufficient, as its full impact on political preferences may require specific domestic institutions

No Relationship Between Preoperative and Early Postoperative Strength After ACL Reconstruction

Context: All rehabilitative programs before ACL reconstructive surgery, which are focused on recovery of proprioception and muscular strength, are defined as prehabilitation. While it has shown that prehabilitation positively affects the overall outcome after ACL reconstruction, it is still controversial whether enhancing preoperatively quadriceps strength has some beneficial effect on postoperative strength, mainly during the first period. Objective: To determine whether there is any relationship between pre- and early postoperative quadriceps strength. Design: Case control. Setting: University research laboratory. Participants: Fifty-nine males (18-33 y; age: 23.69 (0.71) y) who underwent ACL reconstruction with patellar-tendon autograft were examined the day before surgery, at 60 and at 90 days after surgery. Main Outcome Measures: The limb-symmetry-index (LSI) was quantified for maximal voluntary isometric contraction (MVIC) of the knee extensor muscles and of the knee flexor muscles at 90° joint angle. K-means analysis was performed on either quadriceps or hamstrings LSI before surgery to classify the patients in high and low preoperative LSI clusters. Differences in postoperative LSI were then evaluated between the high and low preoperative LSI clusters. Results: Following surgery, there were no differences in the quadriceps LSI between patients with high and low preoperative quadriceps LSI. Sixty days after surgery, the hamstrings LSI was higher in patients with high than low preoperative hamstrings LSI (84.0±13.0% vs 75.4±15.9%; P<0.05). Conclusions: Findings suggest that quadriceps strength deficit is related to the ACL injury and increases further after the reconstruction without any correlation between the pre-operative and postoperative values. Therefore, it appears that there is no need to delay surgery in order to increase the preoperative quadriceps strength before surgery

Asymmetrical lower extremity loading early after ACL reconstruction is a significant predictor of asymmetrical loading at the time of return to sport

OBJECTIVES: The aim of this study was to examine whether asymmetrical lower limb loading early after anterior cruciate ligament reconstruction (1 mo) can predict asymmetrical lower limb loading at the time of return to sport (6 mos) and whether other early predictors as knee joint range of motion or maximal isometric strength affect this relationship. DESIGN: Ground reaction forces were measured during a sit-to-stand task 1 mo after anterior cruciate ligament reconstruction and a vertical countermovement jump 6 mos after anterior cruciate ligament reconstruction in 58 athletes. Other early postoperative measurements were knee joint range of motion (2 wks, 1 mo, and 2 mos after surgery) and maximal isometric strength of the knee extensor and flexor muscles (2 mos after surgery). Linear regression models were developed using side-to-side limb symmetry index (LSI) of countermovement jump as the dependent variable. RESULTS: LSI of sit-to-stand task 1 mo after surgery was a significant independent predictor of LSI of countermovement jump 6 mos after surgery. After accounting for deficits in knee joint range of motion and LSI of maximal isometric strength (ΔR² = 0.35, P < 0.01), LSI of sit-to-stand task predicted LSI of countermovement jump (ΔR² = 0.14 P < 0.01). CONCLUSIONS: Asymmetrical lower extremity loading 1 mo after anterior cruciate ligament reconstruction is an early predictor of asymmetrical lower extremity loading 6 mos after surgery

The RNA-binding protein ESRP1 promotes human colorectal cancer progression

Epithelial splicing regulatory protein 1 (ESRP1) is an epithelial cell-specific RNA binding protein that controls several key cellular processes, like alternative splicing and translation. Previous studies have demonstrated a tumor suppressor role for this protein. Recently, however, a pro-metastatic function of ESRP1 has been reported. We thus aimed at clarifying the role of ESRP1 in Colorectal Cancer (CRC) by performing loss- and gain-of-function studies, and evaluating tumorigenesis and malignancy with in vitro and in vivo approaches. We found that ESRP1 plays a role in anchorage-independent growth of CRC cells. ESRP1-overexpressing cells grown in suspension showed enhanced fibroblast growth factor receptor (FGFR1/2) signalling, Akt activation, and Snail upregulation. Moreover, ESRP1 promoted the ability of CRC cells to generate macrometastases in mice livers. High ESRP1 expression may thus stimulate growth of cancer epithelial cells and promote colorectal cancer progression. Our findings provide mechanistic insights into a previously unreported, pro-oncogenic role for ESRP1 in CRC, and suggest that fine-tuning the level of this RNA-binding protein could be relevant in modulating tumor growth in a subset of CRC patients

A New Perspective on Using Glycols in Glutamate Biosensor Design: From Stabilizing Agents to a New Containment Net

Glutamate is a major excitatory neurotransmitter in the brain. It is involved in many normal physiological brain activities, but also neurological disorders and excitotoxicity. Hence, glutamate measurement is important both in clinical and pre-clinical studies. Pre-clinical studies often use amperometric biosensors due to their low invasiveness and the relatively small size of the devices. These devices also provide fast, real-time measurements because of their high sensitivity. In the present study, diethylene glycol (DEG), neopentyl glycol (NPG), triethylene glycol (TEG), and glycerol (GLY) were used to increase the long-term stability of glutamate biosensors. The evaluation was made by measuring variations of the main enzymatic (VMAX and KM) and analytical (Linear Region Slope (LRS)) parameters. Of the glycols tested, TEG was the most promising stabilizer, showing about twice as high VMAX maintained over a greater duration than with other stabilizers tested. It is also yielded the most stable linear region slope (LRS) values over the study duration. Moreover, we highlighted the ability of glycols to interact with enzyme molecules to form a containment network, able to maintain all the layered components of the biosensor adhering to the transducer

Rheological, mechanical, thermal and electrical properties of UHMWPE/CNC composites

In this work, composites of ultra high molecular weight polyethylene (UHMWPE) and various loadings of cellulose nanocrystals (CNCs) were prepared exploiting different methods. Besides, the microstructure, rheological, mechanical, thermal and electrical properties of the obtained materials were thoroughly investigated. As far as the mechanical behavior of the formulated systems is concerned, CNC-reinforced composites exhibited improved values of Young’s modulus and yielding strength with respect to the unfilled UHMWPE. In particular, the maximum value of ultimate tensile strength was achieved for the systems containing 0.1 wt% of CNCs, and then progressively decreased with increasing the particle loading. As assessed by XRD and DSC analyses, CNC-containing composites showed higher crystallinity degree as compared to the unfilled UHMWPE, suggesting a nucleating effect of embedded CNCs. Morphological and rheological analyses demonstrated that the preparation method involving a solution mixing step is more effective than dry method in promoting the achievement of a peculiar morphology, in which the embedded particles are preferentially located in the interfacial region between UHMWPE grains. Finally, electrical and thermal measurements documented that UHMWPE/CNC composites obtained by solution mixing showed slightly higher thermal conductivity and lower volume resistivity in comparison with the composites prepared by dry method, highlighting that the proper selection of the processing method plays a key role in determining the material final performances

Influence of different dry-mixing techniques on the mechanical, thermal, and electrical behavior of ultra-high molecular weight polyethylene/exhausted tire carbon composites

The mechanical, thermal, and electrical behavior of ultra-high molecular weight(UHMWPE) composites containing different amount of pyrolyzed exhausted tire car-bon (ETC) is investigated. Composites were obtained by dry-mixing the powders with a homogenizer and an impact mill. The results clearly indicate that, by changing the mixing method, it is possible to tune the rheological and morphological characteristics of the composites and in turn their mechanical, thermal, and electrical properties.Better performances were observed for the composites obtained with the impact mill, which showed improved Young modulus, reduced electrical and thermal resistance with respect to those of homogenized counterparts. All the composites exhibited a relevant reduction of electrical resistivity with a percolation threshold of1.51 vol%

Propylene Glycol Stabilizes the Linear Response of Glutamate Biosensor: Potential Implications for In-Vivo Neurochemical Monitoring

L-glutamate is one the most important excitatory neurotransmitter at the central nervous system level and it is implicated in several pathologies. So, it is very important to monitor its variations, in real time in animal models&#8217; brain. The present study aimed to develop and characterize a new amperometric glutamate biosensor design that exploits the selectivity of Glutamate Oxidase (GluOx) for l-glutamate, and the capability of a small molecule as propylene glycol (PG), never used before, to influence and extend the stability and the activity of enzyme. Different designs were evaluated by modifying the main components in their concentrations to find the most suitable design. Moreover, enzyme concentrations from 100 U/mL up to 200 U/mL were verified and different PG concentrations (1%, 0.1% and 0.05%) were tested. The most suitable selected design was Ptc/PPD/PEI(1%)2/GlutOx5/PG(0.1%) and it was compared to the same already described design loading PEDGE, instead of PG, in terms of over-time performances. The PG has proved to be capable of determining an over-time stability of the glutamate biosensor in particular in terms of linear region slope (LRS) up to 21 days

A New Perspective on Using Glycols in Glutamate Biosensor Design: From Stabilizing Agents to a New Containment Net

Glutamate is a major excitatory neurotransmitter in the brain. It is involved in many normal physiological brain activities, but also neurological disorders and excitotoxicity. Hence, glutamate measurement is important both in clinical and pre-clinical studies. Pre-clinical studies often use amperometric biosensors due to their low invasiveness and the relatively small size of the devices. These devices also provide fast, real-time measurements because of their high sensitivity. In the present study, diethylene glycol (DEG), neopentyl glycol (NPG), triethylene glycol (TEG), and glycerol (GLY) were used to increase the long-term stability of glutamate biosensors. The evaluation was made by measuring variations of the main enzymatic (VMAX and KM) and analytical (Linear Region Slope (LRS)) parameters. Of the glycols tested, TEG was the most promising stabilizer, showing about twice as high VMAX maintained over a greater duration than with other stabilizers tested. It is also yielded the most stable linear region slope (LRS) values over the study duration. Moreover, we highlighted the ability of glycols to interact with enzyme molecules to form a containment network, able to maintain all the layered components of the biosensor adhering to the transducer