Minimally invasive vs. open segmental resection of the splenic flexure for cancer: a nationwide study of the Italian Society of Surgical Oncology-Colorectal Cancer Network (SICO-CNN)

Background Evidence on the efficacy of minimally invasive (MI) segmental resection of splenic flexure cancer (SFC) is not available, mostly due to the rarity of this tumor. This study aimed to determine the survival outcomes of MI and open treatment, and to investigate whether MI is noninferior to open procedure regarding short-term outcomes. Methods This nationwide retrospective cohort study included all consecutive SFC segmental resections performed in 30 referral centers between 2006 and 2016. The primary endpoint assessing efficacy was the overall survival (OS). The secondary endpoints included cancer-specific mortality (CSM), recurrence rate (RR), short-term clinical outcomes (a composite of Clavien-Dindo > 2 complications and 30-day mortality), and pathological outcomes (a composite of lymph nodes removed >= 12, and proximal and distal free resection margins length >= 5 cm). For these composites, a 6% noninferiority margin was chosen based on clinical relevance estimate. Results A total of 606 patients underwent either an open (208, 34.3%) or a MI (398, 65.7%) SFC segmental resection. At univariable analysis, OS and CSM were improved in the MI group (log-rank test p = 0.004 and Gray's tests p = 0.004, respectively), while recurrences were comparable (Gray's tests p = 0.434). Cox multivariable analysis did not support that OS and CSM were better in the MI group (p = 0.109 and p = 0.163, respectively). Successful pathological outcome, observed in 53.2% of open and 58.3% of MI resections, supported noninferiority (difference 5.1%; 1-sided 95%CI - 4.7% to infinity). Successful short-term clinical outcome was documented in 93.3% of Open and 93.0% of MI procedures, and supported noninferiority as well (difference - 0.3%; 1-sided 95%CI - 5.0% to infinity). Conclusions Among patients with SFC, the minimally invasive approach met the criterion for noninferiority for postoperative complications and pathological outcomes, and was found to provide results of OS, CSM, and RR comparable to those of open resection

Solid Organ Transplantation During COVID-19 Pandemic: An International Web-based Survey on Resources’ Allocation

Background. Solid organ transplants (SOTs) are life-saving interventions, recently challenged by coronavirus disease 2019 (COVID-19). SOTs require a multistep process, which can be affected by COVID-19 at several phases. Methods. SOT-specialists, COVID-19-specialists, and medical ethicists designed an international survey according to CHERRIES guidelines. Personal opinions about continuing SOTs, safe managing of donors and recipients, as well as equity of resources' allocation were investigated. The survey was sent by e-mail. Multiple approaches were used (corresponding authors from Scopus, websites of scientific societies, COVID-19 webinars). After the descriptive analysis, univariate and multivariate ordinal regression analysis was performed. Results. There were 1819 complete answers from 71 countries. The response rate was 49%. Data were stratified according to region, macrospecialty, and organ of interest. Answers were analyzed using univariate- multivariate ordinal regression analysis and thematic analysis. Overall, 20% of the responders thought SOTs should not stop (continue transplant without restriction); over 70% suggested SOTs should selectively stop, and almost 10% indicated they should completely stop. Furthermore, 82% agreed to shift resources from transplant to COVID-19 temporarily. Briefly, main reason for not stopping was that if the transplant will not proceed, the organ will be wasted. Focusing on SOT from living donors, 61% stated that activity should be restricted only to "urgent"cases. At the multivariate analysis, factors identified in favor of continuing transplant were Italy, ethicist, partially disagreeing on the equity question, a high number of COVID-19- related deaths on the day of the answer, a high IHDI country. Factors predicting to stop SOTs were Europe except-Italy, public university hospital, and strongly agreeing on the equity question. Conclusions. In conclusion, the majority of responders suggested that transplant activity should be continued through the implementation of isolation measures and the adoption of the COVID-19-free pathways. Differences between professional categories are less strong than supposed

Exploring Cosmic Origins with CORE: Cosmological Parameters

We forecast the main cosmological parameter constraints achievable with theCORE space mission which is dedicated to mapping the polarisation of the CosmicMicrowave Background (CMB). CORE was recently submitted in response to ESA'sfifth call for medium-sized mission proposals (M5). Here we report the resultsfrom our pre-submission study of the impact of various instrumental options, inparticular the telescope size and sensitivity level, and review the great,transformative potential of the mission as proposed. Specifically, we assessthe impact on a broad range of fundamental parameters of our Universe as afunction of the expected CMB characteristics, with other papers in the seriesfocusing on controlling astrophysical and instrumental residual systematics. Inthis paper, we assume that only a few central CORE frequency channels areusable for our purpose, all others being devoted to the cleaning ofastrophysical contaminants. On the theoretical side, we assume LCDM as ourgeneral framework and quantify the improvement provided by CORE over thecurrent constraints from the Planck 2015 release. We also study the jointsensitivity of CORE and of future Baryon Acoustic Oscillation and Large ScaleStructure experiments like DESI and Euclid. Specific constraints on the physicsof inflation are presented in another paper of the series. In addition to thesix parameters of the base LCDM, which describe the matter content of aspatially flat universe with adiabatic and scalar primordial fluctuations frominflation, we derive the precision achievable on parameters like thosedescribing curvature, neutrino physics, extra light relics, primordial heliumabundance, dark matter annihilation, recombination physics, variation offundamental constants, dark energy, modified gravity, reionization and cosmicbirefringence. (ABRIDGED

Laparoscopic right hemicolectomy: a SICE (Società Italiana di Chirurgia Endoscopica e Nuove tecnologie) network prospective study on the approach to right colon lymphadenectomy in Italy: is there a standard?—CoDIG 2 (ColonDx Italian Group)

Background: Colon cancer is a disease with a worldwide spread. Surgery is the best option for the treatment of advanced colon cancer, but some aspects are still debated, such as the extent of lymphadenectomy. In Japanese guidelines, the gold standard was D3 dissection to remove the central lymph nodes (203, 213, and 223), but in 2009, Hoenberger et al. introduced the concept of complete mesocolic excision, in which surgical dissection follows the embryological planes to remove the mesentery entirely to prevent leakage of cancer cells and collect more lymph nodes. Our study describes how lymphadenectomy is currently performed in major Italian centers with an unclear indication on the type of lymphadenectomy that should be performed during right hemicolectomy (RH). Methods: CoDIG 2 is an observational multicenter national study that involves 76 Italian general surgery wards highly specialized in colorectal surgery. Each center was asked not to modify their usual surgical and clinical practices. The aim of the study was to assess the preference of Italian surgeons on the type of lymphadenectomy to perform during RH and the rise of any new trends or modifications in habits compared to the findings of the CoDIG 1 study conducted 4 years ago. Results: A total of 788 patients were enrolled. The most commonly used surgical technique was laparoscopic (82.1%) with intracorporeal (73.4%), side-to-side (98.7%), or isoperistaltic (96.0%) anastomosis. The lymph nodes at the origin of the vessels were harvested in an inferior number of cases (203, 213, and 223: 42.4%, 31.1%, and 20.3%, respectively). A comparison between CoDIG 1 and CoDIG 2 showed a stable trend in surgical techniques and complications, with an increase in the robotic approach (7.7% vs. 12.3%). Conclusions: This analysis shows how lymphadenectomy is performed in Italy to achieve oncological outcomes in RH, although the technique to achieve a higher lymph node count has not yet been standardized. Trial registration (ClinicalTrials.gov) ID: NCT05943951

Simulation of PTFE sintering: thermal stresses and deformation behavior

A finite element model has been used to study the sintering process of polytetra-fluoroethylene (PTFE) cylinders in order to predict residual thermal stresses; bothsolid (rods) and hollow (billets) blocks were studied. The simulation of the processwas performed considering three separate stages: thermal, deformation, and stressanalysis. For each stage, relevant material properties were determined experimen-tally. In particular, the deformation behavior of PTFE was thoroughly investigated bymeans of thermo-mechanical analysis (TMA). It is shown that experimental resultscan be explained considering deformation recovery and orientation effects. Predic-tions of the model are compared with experimental measurements performed on realPTFE-sintered cylinders. Temperature and deformation distributions determinedwith the model agree well with experimental data. Fair agreement between predictedand experimentally measured residual stresses is obtained, and the influence of cyl-inder size and applied cooling rate on residual stresses is correctly predicted

Seismic design of CLT buildings: definition of the suitable q-factor by numerical and experimental procedures

The paper discusses the definition of the force modification factor (q-factor) in the literature and its relevance to the design of structures in seismic areas. The available methods for estimating the q-factor are based on the verification of the non-linear seismic response of entire buildings by means of experimental full scale shake table tests or numerical simulations. Such procedures are very expensive from cost and computational points of view. This paper proposes a new procedure for the q-factor evaluation based on a proper application of the pushover method to the load-displacement curve obtained through experimental quasi static tests on representative wall elements. That procedure is validated through shake table tests and numerical simulations on Cross-Laminated-Timber (CLT) building systems. An extensive application of the proposed procedure to a number of CLT shearwall systems tested in the CNR-IVALSA laboratory is presented in order to carry out a reliable estimation of appropriate q-factors. Finally the main advantages and limitations of the proposed procedure are presented and critically discussed

Determination of the fundamental period of CLT buildings via incremental elastic-non linear dynamic analyses

The evaluation of the proper period of vibration is one of the crucial issues in the analysis and seismic design of buildings and is influenced by a number of variables contributing in the definition of the global rigidity and therefore the seismic susceptibility of the structure. In the case of multi-storey X-Lam buildings connection elements play a key role since they are responsible of most of the dissipative and deformative capacity of the structure. The present work aims to investigate the influence of the connection elements typically used to avoid the rocking of the seismic-resistant walls (i.e. hold-down elements) on the fundamental period of multi-storey XLam buildings. A nonlinear numerical model capable of faithfully reproducing the rocking behavior of X-Lam wall system (i.e. accounting for the interaction between the vertical applied loads and the hold-down connection activation) is developed and validated on experimental dynamic tests. The model is used to assess the principal vibration period of a selected case study by means of incremental dynamic analyses. Results from the experimental tests and from the performed analyses demonstrate that when the X-Lam wall system is subjected to significant vertical loads (capable of avoiding the overturning of the walls) the principal vibration period is not affected by the connection stiffness. On the contrary, when negligible vertical loads are applied to the X-Lam wall the principal vibration period is controlled by the hold-down connection stiffness. Finally, the numerical model is also used to characterize the principal vibration period of the case study at different level of the top-displacement adopting seismic input with variable frequency. Results from numerical analyses confirm the strong correlation between the value of principal vibration period and the phenomenon of hold-down connection activation showing an increase of the period increasing the top building displacement

Seismic behaviour of wood-concrete frame shear-wall system and comparison with code provisions

Constructive systems adopting mixed shear walls made of a wood frame and fibrous or cementitious sheets nowadays are largely spread, particularly for prefabricated buildings. The use of gypsum boards as bracing panels is already widely proposed, but also fiber cement or reinforced concrete slabs can be used. The choice of such different materials allows to reach excellent thermal and acoustic insulation performance and for economic reason. Perhaps the demonstration of their sound structural behavior, especially towards the earthquake resistance is still to be given, and their ductility and dissipative capacities still need to be fully assessed even if some experimental tests have already been conducted. Moreover these particular constructive systems are yet not accounted in the building codes (Eurocode 5 and Eurocode 8) and no guidelines are given for their seismic design in order to assure an adequate overstrength of the bracing panels and the adequacy of the fixing system of the panels to the wooden frames. This work reports the investigation of the structural behavior of a newly developed wood-reinforced concrete constructive system. The investigated modular prefabricated system combines a typical platform frame system with an external thin reinforced concrete slab acting as a diaphragm against the horizontal actions and having also thermal ad acoustic functions. The structural design procedure of such innovative system imitates the calculations normally adopted for the platform frame system; the bracing stiffness and strength assured by a OSB panel nailed to the wooden structure are cumulated with those given by the concrete slabs which are screwed to the frame by means of large diameter connectors which assure a considerable stiffness and, in the meantime, a great capacity of energy dissipation in case of seismic events. In order to verify the real performance of this construction system under seismic actions several cyclic tests on single panel modules and on an assembled wall were carried out in accordance with the testing protocol specified in EN 12512. The results of the experimental tests are reported. It has been demonstrated that the seismic performance of the structural system fulfills the requirements given by EC8 for the structures that belong to the higher ductility class. The analytical expressions that best fit the experimental load-displacement curves are reported and the comparison of the obtained results with that calculated according to the analytical formulas given by EC5 for the used connection type are discussed. Finally a FEM nonlinear element able to reproduce the load-displacement hysteretic response of the connectors has been developed and implemented into a finite-element model to understand the mechanical behavior of the studied walls subjected by cyclic load. By the use of the this numerical model it was possible to estimate the seismic performance of the proposed wood-concrete system in terms of ductility and dissipative capacity. Several non-linear numerical analyses were performed and a sound behavior q-factor (i.e. reduction factor) for the wood-reinforced concrete walls was proposed