Measuring preferential market access

One consequence of the proliferation of preferential trade agreements is that an increasing share of international trade is not subject to most favored nation tariffs, but rather enters markets through preferential access. The objective of this paper is to better investigate to what extent preferential market access affects bilateral trade. In doing so, the paper first provides two indices of market access conditions that take into account the complex structure of tariff preferences. One index summarizes direct market access conditions (the overall tariff faced by exports), while the other measures relative market access conditions (the overall tariff faced by exports relative to that faced by foreign competitors). Then, the paper explores the effects of preferential access on international trade by estimating a gravity model augmented by the two indices. The results indicate that both direct and relative market access conditions affect bilateral trade. Although a large majority of countries benefits from the system of preference because of improved direct market access, some countries see part of their benefits eroded, sometimes substantially, by the deterioration in their relative market access conditions

Measuring preferential market access

One consequence of the proliferation of preferential trade agreements is that an increasing share of international trade is not subject to most favored nation tariffs, but rather enters markets through preferential access. The objective of this paper is to better investigate to what extent preferential market access affects bilateral trade. In doing so, the paper first provides two indices of market access conditions that take into account the complex structure of tariff preferences. One index summarizes direct market access conditions (the overall tariff faced by exports), while the other measures relative market access conditions (the overall tariff faced by exports relative to that faced by foreign competitors). Then, the paper explores the effects of preferential access on international trade by estimating a gravity model augmented by the two indices. The results indicate that both direct and relative market access conditions affect bilateral trade. Although a large majority of countries benefits from the system of preference because of improved direct market access, some countries see part of their benefits eroded, sometimes substantially, by the deterioration in their relative market access conditions

A magnetar powering the ordinary monster GRB 130427A?

We present the analysis of the extraordinarily bright Gamma-Ray Burst (GRB) 130427A under the hypothesis that the GRB central engine is an accretion-powered magnetar. In this framework, initially proposed to explain GRBs with precursor activity, the prompt emission is produced by accretion of matter onto a newly-born magnetar, and the observed power is related to the accretion rate. The emission is eventually halted if the centrifugal forces are able to pause accretion. We show that the X-ray and optical afterglow is well explained as the forward shock emission with a jet break plus a contribution from the spin-down of the magnetar. Our modelling does not require any contribution from the reverse shock, that may still influence the afterglow light curve at radio and mm frequencies, or in the optical at early times. We derive the magnetic field ($B\sim 10^{16}$ G) and the spin period ($P\sim 20$ ms) of the magnetar and obtain an independent estimate of the minimum luminosity for accretion. This minimum luminosity results well below the prompt emission luminosity of GRB 130427A, providing a strong consistency check for the scenario where the entire prompt emission is the result of continuous accretion onto the magnetar. This is in agreement with the relatively long spin period of the magnetar. GRB 130427A was a well monitored GRB showing a very standard behavior and, thus, is a well-suited benchmark to show that an accretion-powered magnetar gives a unique view of the properties of long GRBs.Comment: 5 pages, 1 figure, accepted for publication in MNRAS Letter

Lumen-apposing metal stent through the meshes of duodenal metal stents for palliation of malignant jaundice

Background and study aims Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard procedure for malignant jaundice palliation; however, it can be challenging when a duodenal self-expandable metal stent (SEMS) is already in place. Patients and methods The primary aim of our study was to evaluate the technical feasibility of the placement of a lumen apposing metal stent (LAMS) through the mesh (TTM) of duodenal stents. The secondary aims were to evaluate clinical outcomes and adverse events (AEs) related to the procedures. Results Data from 23 patients (11 F and 12 M; mean age: 69.5 ± 11 years old) were collected. In 17 patients (73.9 %) TTM LAMS placement was performed as first intention, while in six patients (26.1 %) it was performed after a failed ERCP. Thirteen patients (56.5 %) underwent the procedure due to advanced pancreatic head neoplasia. One technical failure was experienced (4.3 %). The TTM LAMS placement led to a significant decrease in the serum levels of bilirubin, ALP, GGT, WBC and CRP. No cases of duodenal SEMS occlusion occurred and no other AEs were observed during the follow-up. Conclusions Concomitant malignant duodenal and biliary obstruction is a challenging condition. Palliation of jaundice using TTM LAMS in patients already treated with duodenal stent is associated to promising technical and clinical outcomes

Maintenance sunitinib or observation in metastatic pancreatic adenocarcinoma: a phase II randomised trial

Background: New strategies to prolong disease control warrant investigation in patients with metastatic pancreatic adenocarcinoma. This open-label, randomised, multi-centre phase II trial explored the role of maintenance sunitinib after first-line chemotherapy in this setting. Methods: Patients with pathologic diagnosis of metastatic pancreatic adenocarcinoma, performance status >50%, no progression after 6 months of chemotherapy were centrally randomised by an independent contract research organisation, which was also responsible for data collection and monitoring, to observation (arm A) or sunitinib at 37.5mg daily until progression or a maximum of 6 months (arm B). The primary outcome measure was the probability of being progression-free at 6 months (PFS-6) from randomisation. Assuming P0 = 10%; P1 = 30%, α .10; β .10, the target accrual was 26 patients per arm. Results: 28 per arm were randomised. One arm B patient had kidney cancer and was excluded. Sunitinib was given for a median of 91 days (7-186). Main grade 3-4 toxicity was thrombocytopenia, neutropenia and hand-foot syndrome (12%), diarrhoea 8%. In arm A versus B, PFS-6 was 3.6% (95% confidence interval (CI): 0-10.6%) and 22.2% (95% CI: 6.2-38.2%; P<0.01); 2 y overall survival was 7.1% (95% CI: 0-16.8%) and 22.9% (95% CI: 5.8-40.0%; P = 0.11), stable disease 21.4% and 51.9% (P = 0.02). Conclusion: This is the first randomised trial on maintenance therapy in metastatic pancreatic adenocarcinoma. The primary end-point was fulfilled and 2 y overall survival was remarkably high, suggesting that maintenance sunitinib is promising and should be further explored in this patient population

Prophylactic Clipping After Colorectal Endoscopic Resection Prevents Bleeding of Large, Proximal Polyps: Meta-Analysis of Randomized Trials

Background & Aims The benefits of prophylactic clipping to prevent bleeding after polypectomy are unclear. We conducted an updated meta-analysis of randomized trials to assess the efficacy of clipping in preventing bleeding after polypectomy, overall and according to polyp size and location. Methods We searched the Medline/PubMed, EMBASE, and Scopus databases randomized trials that compared effects of clipping vs not clipping to prevent bleeding after polypectomy. We performed a random-effects meta-analysis to generate pooled relative risks (RRs) with 95% CIs. Multilevel random-effects meta-regression analysis was used to combine data on bleeding after polypectomy and estimate associations between rates of bleeding and polyp characteristics. Results We analyzed data from 9 trials, comprising 7197 colorectal lesions (22.5% 20 mm or larger, 49.2% with proximal location). Clipping, compared with no clipping, did not significantly reduce the overall risk of post-polypectomy bleeding (2.2% with clipping vs 3.3% with no clipping; RR, 0.69; 95% CI, 0.45–1.08; P=.072). Clipping significantly reduced risk of bleeding after removal of polyps that were 20 mm or larger (4.3% had bleeding after clipping vs 7.6% had bleeding with no clipping; RR, 0.51; 95% CI, 0.33–0.78; P=.020) or that were in a proximal location (3.0% had bleeding after clipping vs 6.2% had bleeding with no clipping; RR, 0.53; 95% CI, 0.35–0.81; P<.001). In multilevel meta-regression analysis that adjusted for polyp size and location, prophylactic clipping was significantly associated with reduced risk of bleeding after removal of large proximal polyps (RR, 0.37; 95% CI, 0.22–0.61; P=.021) but not small proximal lesions (RR, 0.88; 95% CI, 0.48–1.62; P=0.581). Conclusions In a meta-analysis of randomized trials, we found that routine use of prophylactic clipping does not reduce risk of post-polypectomy bleeding, overall. However, clipping appeared to reduce bleeding after removal of large (more than 20 mm), proximal lesions

Lumen-apposing metal stents for malignant biliary obstruction: Is this the ultimate horizon of our experience?

In the last years, endoscopic ultrasonography (EUS) has evolved from a purely diagnostic technique to a more and more complex interventional procedure, with the possibility to perform several type of therapeutic interventions. Among these, EUS-guided biliary drainage (BD) is gaining popularity as a therapeutic approach after failed endoscopic retrograde cholangiopancreatography in distal malignant biliary obstruction (MBO), due to the avoidance of external drainage, a lower rate of adverse events and re-interventions, and lower costs compared to percutaneous trans-hepatic BD. Initially, devices created for luminal procedures (e.g., luminal biliary stents) have been adapted to the new trans-luminal EUS-guided interventions, with predictable shortcomings in technical success, outcome and adverse events. More recently, new metal stents specifically designed for transluminal drainage, namely lumen-apposing metal stents (LAMS), have been made available for EUS-guided procedures. An electrocautery enhanced delivery system (EC-LAMS), which allows direct access of the delivery system to the target lumen, has subsequently simplified the classic multi-step procedure of EUS-guided drainages. EUS-BD using LAMS and EC-LAMS has been demonstrated effective and safe, and currently seems one of the most performing techniques for EUS-BD. In this Review, we summarize the evolution of the EUS-BD in distal MBO, focusing on the novelty of LAMS and analyzing the unresolved questions about the possible role of EUS as the first therapeutic option to achieve BD in this setting of patients