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Proportional reasoning is a key topic both at school and in everyday life. However, students are often misled by their preconceptions regarding proportions. Our hypothesis is that these limitations can be mitigated by working on alternative ways of categorizing situations that enable more adequate inferences. Multiple categorization triggers flexibility, which enables reinterpreting a problem statement and adopting a more relevant point of view. The present study aims to show the improvements in proportional reasoning after an intervention focusing on such a multiple categorization. Twenty-eight 4th and 5th grade classes participated in the study during one school year. Schools were classified by the SES of their neighborhood. The experimental group received 12 math lessons focusing on flexibly envisioning a situation involving proportional reasoning from different points of view. At the end of the school year, compared to a control group, the experimental group had better results on the posttest when solving proportion word problems and proposed more diverse solving strategies. The analyses also show that the performance gap linked to the school's SES classification was reduced. This offers promising perspectives regarding multiple categorization as a path to overtake preconceptions and develop cognitive flexibility at school.

In problem solving situation, cognitive flexibility appears tobe a major skill. Fostering cognitive flexibility is therefore aspecific stake in mathematics education. This researchintroduces a learning method to develop mathematicalconcepts when solving word arithmetic problems. The studywas conducted with 8 classes (4 th -5 th Grades) from high-priority education schools in the Paris area following thisprotocol: pre-tests, 5 learning sessions for experimental andcontrol groups, post-tests. During learning sessions, studentsstudied arithmetic word problems that can be solved in twodifferent ways: an expansion strategy and a factorization one.The experimental teaching method, based on arecategorization principle, allowed experimental students toimprove more than the control students in ability to use thefactorization strategy even in contexts where it is the lessintuitive and to consider the two successful strategies.Educational entailments of our finding are discussed.

Maize tortilla is the best-recognized food product of Mexican gastronomy. Artisanal maize tortillas (AMT) are prepared with native maize varieties and a traditional process. The aims of this study were to identify sensory attributes, texture, and color in AMT that allow them to be differentiated from commercial tortillas, and to determine the chemical and mineral composition of both types of tortillas. Six landraces related to four Mexican maize races were used. Two commercial tortillas were included as references (tortillería and supermarket). Tortillas were subjected to sensory analysis by the modified Flash technique, texture and color were measured objectively and chemical and mineral analysis of all tortillas were evaluated. Lime taste and lime smell attributes were relevant to differentiate AMT from commercial tortillas; aftertaste and fracturability attributes were highly associated to supermarket tortillas. The fracturability attribute of tortillas is consider undesirable for taco preparation. Five of the six AMT were characterized by the presence of a layer, a characteristic that is associated with traditional tortilla made by Mexican consumer. Regarding chemical composition, supermarket tortillas exhibited the highest dietary fiber content (17.09%), but showed 30% more Na than AMT, with the exception of tortillas from Purepecha native variety. Besides, supermarket tortilla had 48.9% less Ca than AMT. The sensory attributes relevant to differentiate native maize tortillas from the commercial maize tortilla references were appearance, smell, and taste, while textural and color attributes played a lesser role.

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Abstract Background East and South East Asian subjects as well as Amerindians and Hispanic subjects are predominantly affected by Vogt-Koyanagi-Harada disease. In Europe, only few studies have described the clinical features and treatment of this disease, especially in France. Methods This retrospective case series was based on data collected from patients with a VKH disease diagnosed from January 2000 to March 2017, provided by three French Tertiary Centers. Results Forty-one patients (16 men and 25 women) were diagnosed: average age at diagnosis was 38.7 years. Patients were mainly from Maghreb (58%), but ethnic origins were multiple. Pleiocytosis was observed in 19 cases (63%) and 17 out of 41 patients showed audio vestibular signs (41%), and 11 showed skin signs (27%). Thirty-four were treated with corticosteroids (83%), 11 with an immunosuppressant treatment (27%) and 5 with biological therapy drugs (13%). Relapse was observed in 41% patients, even though final average visual acuity had improved. We did not find any significant clinical difference in the population from Maghreb compared to other populations, but for age and sex trends, since there was a majority of younger women. Conclusion We report here the second largest French cohort reported to date to our knowledge. The multiethnicity in our study suggests that VKH disease should be evoked whatever patients’ ethnicity.

The analysis of the vertical movements of the soil in the Po River plane of the Emilia-Romagna Region (Italy) was updated through an interferometric analysis referred to the 2011–2016 time-span. This activity is a continuation of previous studies on the state of knowledge of vertical soil movements in the same area, analyzed firstly by levelling and GNSS and more recently by SAR interferometry for the periods 1992–2000, 2002–2006, 2006–2011, on behalf of the Emilia-Romagna Region. The survey area analysed was approximately 13 300 km2, which corresponds to the territory of the regional plain. The interferometric dataset was calibrated through the use of velocity time series of several permanent GNSS stations. Among the 36 stations analysed, 22 were included in the study area: 16 were used for the calibration and 6 as check points). The velocities required for the calibration of the SAR analysis were calculated in the period following the important seismic events that struck the territory of the Emilia Romagna Region in May 2012. The interferometric analysis was carried out by TRE ALTAMIRA using the SqueeSAR™ technology. In particular, in order to update the interferometric dataset to 2016, it was necessary to perform a joint processing of the available RADARSAT-1 data and of the data acquired by the RADARSAT-2 satellite using a specific operating mode of the SqueeSAR™ algorithm known as stitching; this approach allowed the joint processing of images acquired in the same geometry by these two satellites. The study of the time series of the GNSS permanent stations used to provide the velocity datum to the interferometric analysis, is described, and the results of the SqueeSAR™ interferometric processing are reported. Statistical analyses on the spatial distribution and the type of scatterers have been performed during the screening and validation procedures of the dataset, and for the identification and removal of the outliers. Finally, the resulting map is described in order to analyse the measured soil movements with respect to the results obtained in past analyses, and the possible geological and human-induced causes, which could have produced them.

Multiple processes contributing to natural land subsidence in a shallow coastal aquifer near Ravenna (Italy) were identified by analysing the relationships among different data set time series (water table level, rainfall, land reclamation drainage, sea level, etc.) and establishing the correlations with vertical ground motion observed at a high-resolution settlement gauge. Our study highlights the presence of three deformation components related to different processes controlling land subsidence: elastic, delayed-elastic, and irreversible (plastic) components. The elastic and delayed-elastic components are closely related to water table fluctuations that change the effective stress in two portions of the coastal aquifer at a daily (in the sandy unconfined portion) and seasonal time scales (in the layered clay-rich semi-confined prodelta portion), respectively. The irreversible component represents the trend in the land subsidence time series and is due to primary consolidation (pore pressure dissipation) of the fine-grained prodelta levels above where the settlement gauge is located. The amplitudes of the elastic component can be up to 0.2–0.3 mm whereas the amplitude of the delayed-elastic component reaches 0.89 mm. The primary consolidation rate of deformation is 0.9 mm yr−1 and constrains the likely age of prodelta sediments deposition to 1300–2800 years before present. The delayed-elastic subsidence rate has similar magnitude to that due to primary consolidation and is connected to poroelastic effects in the prodelta sequence following seasonal variations in water table. Our findings are important for planning land subsidence management and monitoring strategies especially where the surface aquifer structure is heterogeneous due to different depositional settings. The natural land subsidence rate in the Holocene sediments of the shallow coastal aquifer of Ravenna (North eastern Italy) that we measured in this study accounts for 10 %–20 % of the total current land subsidence rate observed in this portion of Ravenna coastal area (10–20 mm yr−1).

Abstract Background Postoperative pulmonary complications (PPC) may result in longer duration of in-hospital stay and even mortality. Both thoracic surgery and intraoperative mechanical ventilation settings add considerably to the risk of PPC. It is unclear if one-lung ventilation (OLV) for thoracic surgery with a strategy of intraoperative high positive end-expiratory pressure (PEEP) and recruitment maneuvers (RM) reduces PPC, compared to low PEEP without RM. Methods PROTHOR is an international, multicenter, randomized, controlled, assessor-blinded, two-arm trial initiated by investigators of the PROtective VEntilation NETwork. In total, 2378 patients will be randomly assigned to one of two different intraoperative mechanical ventilation strategies. Investigators screen patients aged 18 years or older, scheduled for open thoracic or video-assisted thoracoscopic surgery under general anesthesia requiring OLV, with a maximal body mass index of 35 kg/m2, and a planned duration of surgery of more than 60 min. Further, the expected duration of OLV shall be longer than two-lung ventilation, and lung separation is planned with a double lumen tube. Patients will be randomly assigned to PEEP of 10 cmH2O with lung RM, or PEEP of 5 cmH2O without RM. During two-lung ventilation tidal volume is set at 7 mL/kg predicted body weight and, during OLV, it will be decreased to 5 mL/kg. The occurrence of PPC will be recorded as a collapsed composite of single adverse pulmonary events and represents the primary endpoint. Discussion PROTHOR is the first randomized controlled trial in patients undergoing thoracic surgery with OLV that is adequately powered to compare the effects of intraoperative high PEEP with RM versus low PEEP without RM on PPC. The results of the PROTHOR trial will support anesthesiologists in their decision to set intraoperative PEEP during protective ventilation for OLV in thoracic surgery. Trial registration The trial was registered in clinicaltrials.gov (NCT02963025) on 15 November 2016.

Copyright of Activités is the property of ARPACT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Postoperative pulmonary complications (PPCs) increase the morbidity and mortality of surgery in obese patients. High levels of positive end-expiratory pressure (PEEP) with lung recruitment maneuvers may improve intraoperative respiratory function, but they can also compromise hemodynamics, and the effects on PPCs are uncertain. We hypothesized that intraoperative mechanical ventilation using high PEEP with periodic recruitment maneuvers, as compared with low PEEP without recruitment maneuvers, prevents PPCs in obese patients. Methods/design The PRotective Ventilation with Higher versus Lower PEEP during General Anesthesia for Surgery in OBESE Patients (PROBESE) study is a multicenter, two-arm, international randomized controlled trial. In total, 2013 obese patients with body mass index ≥35 kg/m2 scheduled for at least 2 h of surgery under general anesthesia and at intermediate to high risk for PPCs will be included. Patients are ventilated intraoperatively with a low tidal volume of 7 ml/kg (predicted body weight) and randomly assigned to PEEP of 12 cmH2O with lung recruitment maneuvers (high PEEP) or PEEP of 4 cmH2O without recruitment maneuvers (low PEEP). The occurrence of PPCs will be recorded as collapsed composite of single adverse pulmonary events and represents the primary endpoint. Discussion To our knowledge, the PROBESE trial is the first multicenter, international randomized controlled trial to compare the effects of two different levels of intraoperative PEEP during protective low tidal volume ventilation on PPCs in obese patients. The results of the PROBESE trial will support anesthesiologists in their decision to choose a certain PEEP level during general anesthesia for surgery in obese patients in an attempt to prevent PPCs. Trial registration ClinicalTrials.gov identifier: NCT02148692. Registered on 23 May 2014; last updated 7 June 2016.

The aim of this study was the assessment of the physicochemical stability of d-α-tocopherol formulated in medium chain triglyceride nanoemulsions, stabilized with Tween®80 and Lipoid®S75 as surfactant and co-surfactant, respectively. d-α-tocopherol was selected as active ingredient because of its well-recognized interesting anti-oxidant properties (such as radical scavenger) for food and pharmaceutical industries. A series of nanoemulsions of mean droplet size below 90 nm (polydispersity index

Bullae formation on a cystic background is still not described thoroughly. This clinical case aims to improve this situation and describes the combination of multiple cysts with vascular malformation, giant bullae (2/3 of the left hemithorax and 1/2 of the right hemithorax) with suppuration in a 50-year-old smoker. Before surgery, treatment for chronic obstructive lung disease (COPD) was administered without a positive outcome. Bullectomy was subsequently conducted and histopathological data revealed vascular malformation causing microinfarctions in pulmonary parenchyma, cystic degeneration and tuberculosis. Although it became possible to establish a final diagnosis due to histology, the need for surgical treatment was clear from clinical and x-ray evidence.Such instances as the one presented in this case report should assist with improving our knowledge about bullae in combination with cysts in the lungs because they provide additional context in a clinical setting.

Paracetamol (PAR), phenylephrine hydrochloride (PHE) and chlorpheniramine maleate (CPM) are commonly used in clinical practice as antipyretic and analgesic drugs to ameliorate pain and fever in cold and flu conditions. The present work describes the use of thermal analysis for the characterization of the physicochemical compatibility between drugs and excipients during the development of solid dosage forms. Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) were used to study the thermal stability of the drug and of the physical mixture (drug/excipients) in solid binary mixtures (1:1). DSC thermograms demonstrated reproducible melting event of the prepared physical mixture. Starch, mannitol, lactose and magnesium stearate influence thermal parameters. Information recorded from the derivative thermogravimetric (DTG) and TGA curves demonstrated the decomposition of drugs in well-defined thermal events, translating the suitability of these techniques for the characterization of the drug/excipients interactions.

Studies on release systems produced from natural polymers such as chitosan (CS) have intensified in the pharmaceutical area. Polymeric membranes for the topical administration of drugs are being developed for the controlled release of drugs. Thus, the present study aimed to develop mucoadhesive polymer membranes for topical administration of the anesthetic, lidocaine hydrochloride (LID), for topical use. The methodology was done by a casting method using CS, propylene glycol (PPG) as the plasticizer in the concentrations of 0.2, 0.4 and 0.8% and lidocaine hydrochloride (LID). The membranes were characterized by mechanical properties, swelling index, thermal analysis and cell viability in vitro. Results showed membranes containing PPG containing the plasticizing agent was greater flexibility, better swelling profile and higher thermal resistance. In the cell viability assay with HaCat and 3T3 cells, it was possible to observe that all samples showed viability higher than 60 %. Thus, according to the results obtained in this study, it was possible to conclude that this pharmaceutical form is promising for the therapeutic use in topical administration aiming at the anesthetic action.

The aim of this study was to investigate the possible antioxidant and anticancer activities of the essential oil from the leaves of Croton argyrophyllus Kunth (EOCA). In order to evaluate the antioxidant effect, two tests were performed: 1) in vitro lipid peroxidation activity, at the concentrations of 50, 100 and 200 µg/mL, with a reduction in malondialdehyde (MDA) values of 4.26 ± 0.15, 2.92 ± 0.16 and 1.61 ± 0.27 nmol EqMDA/mL, respectively; 2) activity against DPPH, at concentrations between 50 and 150 µg/mL, with IC50 187.61 µg/mL. For the evaluation of a possible anticancer activity of EOCA, the in vitro cytotoxic activity was first determined on cultured tumor cells, showing IC50 values of 14.81 µg/mL, 21.86 µg/mL and 32.79 µg/mL against SF-295, OVCAR-8, and MDA/MB-435, respectively. For tumor cell lines HCT-8 and HL-60, the IC50 values were > 50 µg/mL for both cells. Besides those, hemolytic assay, evaluation of in vivo tumor growth and systemic toxicological evaluation were performed, but no significant statistical change was observed. In conclusion, the EOCA has antioxidant activity and anticancer activity in vitro against cancer cell lines tested without in vivo antitumor activity.

After publication of the original article [1], the authors have notified us that two of the collaborator first and last names have been inverted in the “PROTHOR Investigators” table.