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Safety of infrastructures represents one of the most significant concerns for governments and service providers to preserve people's well-being. One of the main ways to keep in safe facilities (buildings, bridges, railways, etc.) involves the use of monitoring sensor systems in charge of measuring critical operating conditions. Those measurements together with periodical maintenance, contribute to minimize potential risks that the infrastructure faces. The paper aims at designing, developing, and testing a monitoring system for mechanical stresses acting on the overhead contact wire (OCW) to ensure the operational safety of the railway network. In this regard, the paper proposes two Fiber Bragg Grating (FBG) sensors-based solutions, relying on the ability of these sensors to allow real-time and continuous data acquisition. The first one consists in a polyimide-coated sensor bonded on an OCW clamp, the second one is a copper-coated sensor hanging between the two separated halves of an OCW clamp. Significant results have been obtained mechanically testing both solutions, trying to simulate the operative conditions.

Abstract The recycling of lead acid batteries (LABs) comprises relevant concerns on the suitable methodologies to recover lead. In this investigation, two electrorefining processes, by using acidic and alkaline electrolytes, have been compared to determine the most significant results of both methodologies. Acidic electrolytes used 200 g/L HBF4, 1.2 g/L H3PO4, 10 g/L H3BO3, and 100 g/L PbO, while the alkaline ones employed 120 g/L NaOH, 75 g/L PbO, 50–92 g/L glycerol, and 2 g/L gelatin. All the solutions were studied by varying temperature and current density (CD) to determine remarkable changes on current efficiency (CE), cell voltage (CV), specific energy consumption (SEC), and on the deposit quality. The results highlighted that by using the acidic electrolyte containing dextrin it is possible to obtain a compact deposit even using high CDs. Acidic solution without dextrin addition allows to obtain good quality deposits by working at 40 °C and 100 A/m2 CD. After testing the behavior of different alkaline electrolytes, it is possible to observe that the solution containing the highest glycerol concentration allows to obtain, for intermediate valued of CD, CE higher than 97% with a SEC of about 0.37 kWh/kg. By comparing the results it is evident that the acidic electrolyte is the one that allows to reach higher productivity with lower SEC. In the selected conditions, lead deposits appear pure and compact. Graphical Abstract

Lead acid batteries are processed mainly by using pyrometallurgical operations with problems related to SO2 evolution. Many efforts have been devoted to solving this concern. In this work, where only the anode preparation was a pyrometallurgical process, this problem has been overcome by limiting the process temperature. Several tests have been carried out in order to determine the starting mix composition that allows to reduce the process temperature and then SO2 emissions. Three different anode types were cast and tested. Independently on the anode type, the complex composition of the anode requires to design a special electrolytic cell composed by two different compartments. Preliminary electrorefining tests highlighted that the best results were obtainable by using the anode cast in a titanium holder that allowed to obtain high-purity lead, high anode durability, and low quantity of anodic mud. By using this anode, the specific energy consumption varied over the 0.04–0.17 kWh/kg range.

Electrowinning represents a promising methodology for recovery of strategical, scarce metals. In this study, an indium electrowinning process using a sulfate electrolyte on stainless steel, nickel, titanium, aluminum and copper (SS, Ni, Ti, Al and Cu) cathodes was investigated. Firstly, cyclic voltammetry carried out at 15 mV/s scanning rate and 25 °C temperature evaluated the suitability of electrolyte and the surface reactivity on different metal cathodes. Subsequently, indium was deposited using a current density of 25 A/m2 for 22 h at 40 °C and pH 2.3. After electrowinning process, analysis of specific energy consumption (SEC), current efficiency (CE) morphological (SEM/EDX), and crystallographic (XRD) tests on obtained deposits were performed. Cyclic voltammetry results revealed that the chemical reagents of solution stabilize the indium reduction reaction, while Ni cathode showed the highest current intensity for reduction reaction followed by SS, Ti, Cu, and Al. With a significant CE and SEC performance, Ni and SS cathodes reached around 93 % CE and 1.67 kW h/kg SEC, respectively. Referring to Ti cathode, other optimization tests should be performed to enhance obtained results. After deposition process, different surface morphologies and different crystallinity degree can be observed for each deposit, being common the presence of surface defects. The findings of this investigation allowed to determine the most suitable cathode for indium electrowinning from sulfate electrolyte.

In 2015, the Association of American Medical Colleges implemented an interinstitutional pilot of 13 core entrustable professional activities (EPAs) for entering residency, activities that entering residents should be expected to perform with indirect supervision. The pilot included a concept group on faculty development; this group previously offered a shared mental model focused on the development of faculty who devote their efforts to clinical teaching and assessment for learning and entrustment decision making. In this article, the authors draw from the literature of competency-based education to propose what is needed in overall approaches to faculty development to prepare institutions for undergraduate EPA implementation.Taking a systems-based view that defines the necessary tasks of EPA implementation, the authors move beyond the variably used term "faculty" and enumerate a comprehensive list of institutional stakeholders who can meaningfully support and/or engage in the relationships and organizational processes required for EPA learning and assessment. They consider each group's responsibilities and development needs according to five domains delineated by Steinert: teaching improvement, leadership and management, research-building capacity, academic career building, and organizational change.The authors argue that the EPA framework addresses barriers posed with the use of a competency-based framework. By facilitating the communication required for organizational change, enabling valid assessment with comprehensive yet feasible levels of faculty development, and incorporating all relevant data on student professional behavior into summative assessment decisions, EPAs may offer a clearer path toward the goal of competency-based education.

The medical education literature is beginning to address the educational effects of summative closed-response (MCQ) and open-response (short answer) exam formats. This study examines the student-reported educational effects of these types of testing. From 2013 to 2016, an open-response summative “diagnostic reasoning examination” (DxRx) has been administered in the Reproductive Systems Module. The DxRx consists of unfolding cases requiring short answers and a final explanation of pathophysiology. The module also utilizes an NBME MCQ examination. Annually, the authors have queried students on their preparation for these examinations in post-course surveys. Narrative responses were categorized using three domains from a validated framework: cognitive processing, resources, and content. The average survey response rate was 72.5% (n = 343). The percentage indicating their study strategy for the DxRx differed from the NBME exam ranged from 81.6 to 97.9%. Ninety percent of respondents provided comments. On cognitive processing, 38% reported re-organizing course content by clinical presentation (rather than studying disease in isolation), 18% described developing and/or practicing generation of differential diagnoses, 14% reported shifting to group study. Students reported using case-based material and focusing on content directly related to clinical problem-solving. Ten percent of students volunteered metacognitive insights suggesting more robust learning from DxRx preparation. The majority of students reported different approaches to studying for the DxRx that support constructing new knowledge and the cognitive skills required for clinical problem-solving. We believe these findings represent an important step in exploring the educational effect of these two types of summative testing.

Use of fiber Bragg gratings (FBGs) to monitor high temperature (HT) applications is of great interest to the research community. Standard commercial FBGs can operate up to 600 ∘ C. For applications beyond that value, specific processing of the FBGs must be adopted to allow the grating not to deteriorate. The most common technique used to process FBGs for HT applications is the regeneration procedure (RP), which typically extends their use up to 1000 ∘ C. RP involves a long-term annealing of the FBGs, to be done at a temperature ranging from 550 to 950 ∘ C. As at that temperature, the original coating of the FBGs would burn out, they shall stay uncoated, and their brittleness is a serious concern to deal with. Depositing a metal coating on the FBGs prior to process them for RP offers an effective solution to provide them with the necessary mechanical strengthening. In this paper, a procedure to provide the FBG with a bimetallic coating made by copper and nickel electrodeposition (ED) is proposed, discussing issues related to the coating morphology, adherence to the fiber, and effects on the grating spectral response. To define the processing parameters of the proposed procedure, production tests were performed on dummy samples which were used for destructive SEM&ndash, EDS analysis. As a critical step, the proposed procedure was shown to necessitate a heat treatment after the nickel ED, to remove the absorbed hydrogen. The spectral response of the FBG samples was monitored along the various steps of the proposed procedure and, as a final proof test for adherence stability of the bimetallic coating, along a heating/cooling cycle from room temperature to 1010 ∘ C. The results suggest that, given the emergence of Kirkendall voids at the copper&ndash, nickel interface, occurring at the highest temperatures (700&ndash, 1010 ∘ C), the bimetallic layer could be employed as FBG coating up to 700 ∘ C.

PROBLEM In 2014, medical students at the Florida International University Herbert Wertheim College of Medicine (FIU HWCOM) first drew attention to perceived gaps in the sexual health curriculum. The authors used Kern and colleagues' model for curriculum development to review and update the existing curriculum. APPROACH To develop longitudinal sexual health curricular objectives for undergraduate medical education (UME), the authors reviewed existing specialty- and organization-specific objectives. Then, an iterative process guided by clear criteria was used to develop feasible objectives, which were refined through stakeholder feedback. As these objectives were being finalized in 2017, UME sexual health competencies were first published; the authors mapped their objectives to these, as possible. The medical school's course activities and assessments were mapped to the authors' sexual health objectives to identify curricular gaps and unplanned redundancies. OUTCOMES This process resulted in 12 sexual health curricular objectives that are adaptable by other institutions. In mapping the FIU HWCOM curriculum to these objectives, specific gaps and assessment weaknesses emerged. With stakeholder support obtained through a strong curricular management structure, the work of modifying content to address gaps has begun. NEXT STEPS New assessments specific to these sexual health objectives are needed, especially within the clinical curriculum. Assessment of these objectives may be strengthened through the development of new sexual-health-related entrustable professional activities (EPAs) nested within the broader Core EPAs for Entering Residency being piloted. When data on learning outcomes are available, the process of targeting curricular improvement will begin.

Introduction Many patients receiving news of an unplanned pregnancy need not only a test result, but also the initiation of pregnancy options counseling. Thus, this online instructional module and objective structured clinical examination (OSCE) aim to provide foundational training for medical students in nondirective pregnancy options counseling. Methods To further the validity of a previously published OSCE, we reconsidered content, revised the checklist, and produced videos for rater training. We also developed a 30-minute preparatory module outlining a stepwise approach and providing a structured opportunity for values clarification. The 10-minute OSCE scenario involves a 24-year-old woman presenting to an urgent care center with persistent nausea who receives the diagnosis of an early, unplanned pregnancy. She responds to the news with shock and emotional silence, asking for guidance. We conducted the OSCE with 46 third-year medical students on the family medicine clerkship. Immediately after the OSCE, students completed a survey and self-assessment, followed by an individualized feedback session with a faculty member. Results In the self-assessment phase, students reflected on how successfully they utilized methods in the online module for handling emotional silence and presenting options. Student self-identified areas for improvement highlighted use of terminology and their response to difficult emotional encounters in the future. Discussion This online module and validated OSCE provide a valued opportunity for learners to practice nondirective pregnancy options counseling skills, including screening for intimate partner violence and reproductive coercion, engagement in self-assessment and receiving feedback, and engaging in personal values clarification.

Indium electrowinning process from sulfate solution on copper, titanium and aluminum cathodes (Cu, Ti and Al) were studied using the methods of cyclic voltammetry (CV) and chronoamperometry (CA). Voltammogram features indicated the irreversible behavior of indium discharge on each cathode. The heterogeneous charge transfer rate constant (k0) has been evaluated on Cu, Ti and Al cathodes and their values were 7.1·10−5 cm/s, 6.2·10−5 cm/s and 5.4·10−5 cm/s, respectively. The indium ions electro-reduction seems to be quite different on these diverse cathodic supports: a nucleation process appears on Cu and Al cathodes, while is absent on Ti cathode due to the hydrogen evolution overlapping at high cathodic overpotentials. CV and CA techniques allowed to calculate the diffusion coefficient (D0) of indium ion in sulfate solution. Furthermore, calculating the roughness coefficient (φ) by CV technique on each metal surface, it was possible to establish the real surface area of Cu, Ti and Al cathodic supports. The charge transfer coefficient values (α) calculated by Tafel curves agreed those obtained by CV results, while the k0 value and the exchange current density (i0) showed a similar trend for each cathode. By these results, the exchange current density was equal to 1.20 mA/cm2, 0.30 mA/cm2 and 0.075 mA/cm2 for Cu cathode Ti and Al cathodes, respectively. The findings of this investigation can provide an understanding of the indium electrowinning process on three different support electrodes (Cu, Ti and Al) from sulfate solution.

Objective Limitations on didactic time pose barriers to teaching non-directive pregnancy options counseling. This study set out to explore the use of an online module to support trainee performance in a pregnancy options counseling standardized-patient exercise implemented among third-year medical students, and to examine the effect of clinical experience on student performance. Study design An online module was developed. A convenience sample of forty-six student performances in a family medicine clerkship participated in a standardized patient exercise. Trained faculty rated performances. Students completed a self-assessment and provided feedback on the online module. Chi-square and Mann–Whitney-U tests were used to analyze data. Three coders qualitatively examined narrative student comments. Results Thirty-four students passed, 11 achieved a minimal pass, and one failed. The mean global rating from faculty was 2.8 (pass). Students with prior clinical experience significantly outperformed those without on the global rating scale with mean scores of 3.1 compared to 2.7, respectively (p = .044). All students agreed that the online module helped prepare them for the exercise. Qualitative analysis of students' feedback on the module revealed strengths in content and pedagogy. In their self-assessments, all but two students referred to content explicitly conveyed in the module. Conclusion All students agreed that an online module supported their performance of non-directive pregnancy options counseling skills. Prior clinical experience was associated with improved performance. This module, along with the simulated exercise, can be implemented as a blended learning exercise without additional faculty teaching effort in standardized patient resource centers. Implications Students agreed that an online module facilitates simulated performance of non-directive pregnancy options counseling skills. Future work should compare the impact of this approach to others, and explore the additional training needed to maintain and build on initial learning.

Cast iron pipelines are still utilized for water and gas transportation. Recently several dangerous events occurred. Thus the study of both endogenous and exogenous critical issues on cast-iron pipelines is again of interest. Those critical issues have been analyzed, also considering some actual cases. Experimental results, obtained from tests performed on lamellar cast iron coming from pipes broken in works, have been reported. Particularly toughness, crack growth rate and UTS have been determined by considering also the defectiveness and corrosion conditions of the studied material. A system for cast iron pipelines monitoring is proposed.

Recently, rechargeable Li S batteries, a next-generation energy storage system, are deeply studied due to their theoretical specific energy density. However, to produce batteries comparable to those already available on the market some drawbacks must be overcome, including essentially self-discharge, high internal resistance and rapid capacity fading upon cycling. In this work the use of polysulfide solutions either as additives or as active material in Li S batteries is proposed. The addition of polysulfides to the electrolytic solution improves the cell performances in terms of specific capacity and coulombic efficiency, passing from a capacity of about 150 mAh/g with a coulombic efficiency of about 0.85 to a capacity of 600 mAh/g with a coulombic efficiency of about 0.99 after 10 cycles. In batteries where polysulfide solutions are used as cathodic material, the obtained performances are even higher, reaching specific capacities of 420–450 mAh/g after about 70 cycles. Moreover, the cells tested with carbon paper as electrode support shows a greater reversibility, with a coulombic efficiency very close to 1. Finally, reducing the potential window from 3 to 1.5 V to 2.8–1.7 V, the cells show high stability and efficiency, reaching specific capacity values of about 600 mAh/g after 200 cycles.

Since indiumisconsidereda strategic material, a study for developing and optimizing a recovery process by electrowinning has been performed. The possibility of using electrolytic baths based on sulfates instead of chlorides has also been evaluated. Nowadays, chlorides are widely used because they generally present greater current efficiencies;however, the dangers of chlorine gasrequireexpensive-sealed systems to avoid human health and environmental issues. The use of sulfatesdoes not present the same problems;therefore the electrowinning process optimization can represent a definite indium recovery improvement. For this purpose, the effects of electrolyte composition, temperature, current density and pH on the quality of the deposit, specific energy consumption (SEC) and current efficiency (CE) have been assessed. The sulfate electrolytic solutionhas been then appropriately modified with organic additives, mineral salts and complexing agents to optimize the indium recovery by electrowinning. ACE of about80% and SEC equal to 2.7 kWh/kg have been obtained, operating with a pH in the range 2.2–2.3 at 40 °C and using 25 A/m2 current density with an electrolytic solution containing 60 g/l of In3+, 30 g/l of Na2SO4, 20 g/l of Al2(SO4)3 and 20 g/l of H3BO3.

Selective extraction of Zn(II) from industrial leach solutions containing Fe, Ni and Co is still a challenging task. In this paper solvent extraction of Zn(II) with D2EHPA and 5% saponified D2EHPA from sulphuric solutions has been performed. Experimental tests carried out on concentrated solutions allowed to select the operative conditions that allow to obtain both high Zn(II) extraction yield and selectivity. On the basis of the experimental results, a separation process has been proposed for the selective recovery of Zn from a solution containing 60 g/L of Zn. Zn extraction with saponified D2EHPA has been carried out in two different steps. In the first one 2 M D2EHPA has been used for extracting Fe(III) and part of Zn, while in the second one 1 M D2EHPA has been used for recovering the remaining Zn with less than two theoretical stages.

This article was migrated. The article was marked as recommended. Introduction: A graduating medical student should be competent in both teaching and communication skills. This concept is supported by the Accreditation Council for Graduate Medical Education and the Association of American Medical Colleges. Our study describes how we utilized problem-based learning as a platform for developing student teaching skills and to examine preliminary outcomes. Methods: Since 2013, third-year medical students at Florida International University Herbert Wertheim College of Medicine have participated in a mandatory problem-based learning course in parallel to their clinical rotations. During the course orientation students have been led through interactive sessions on writing learning objectives and methods for effective micro-teaching sessions. During seven subsequent sessions, trained faculty members have assessed and provided narrative comments on students' "Ability to Teach Peers" using an anchored developmental scale rubric. Data from four academic years were available for analysis. The Wilcoxon signed-rank test was used to test differences between the initial and final sessions. Results: At the initial session, 39.0% (n=147) received ratings of "mastering." By the final session, 62.6% (n=236) received ratings of "mastering." Conclusion: Our preliminary work demonstrates that a brief orientation to micro-teaching followed by repeated mandatory practice and feedback within our problem-based learning curriculum may serve to build students' teaching skills.

Fiber optics with photo-imprinted Bragg grating have been studied in order to be used as temperature sensors in cryogenic applications. The main disadvantage presented by Fiber Bragg Grating (FBG) sensors is the significant drop in sensitivity as temperature decreases, mainly due to the critical lowering of the thermo-optic coefficient of the fiber and the very low thermal expansion coefficient (CTE) of fused silica at cryogenic temperatures. Thus, especially for the latter, it is important to enhance sensitivity to temperature by depositing a metal coating presenting higher CTE. In this work the thermal sensitivity of metal-coated FBG sensors has been evaluated by considering their elongation within temperature variations in the cryogenic range, as compared to bare fiber sensors. To this purpose, a theoretical model simulating elongation of metal-coated sensors has been developed. The model has been used to evaluate the behaviour of different metals which can be used as coating ( Ni , Cu , Al , Zn , Pb and In). The optimal coating thickness has been calculated at different fixed temperature (from 5 K to 100 K) for each metal. It has been found that the metal coating effectiveness depends on thickness and operating temperature in accordance to our previous experimental work and theory suggest.

The synthesis of organic-inorganic hybrid compounds based on phenylphosphonate and their use as precursors to form LiMnxFe(1−x)PO4 composites containing carbonaceous substances with sub-micrometric morphology are presented. The experimental procedure includes the preliminary synthesis of Fe2+ and/or Mn2+ phenylphosphonates with the general formula Fe(1−x)Mnx[(C6H5PO3)(H2O)] (with 0 < x < 1), which are then mixed at different molar ratios with lithium carbonate. In this way the carbon, obtained from in situ partial oxidation of the precursor organic part, coats the LiMnxFe(1−x)PO4 particles. After a structural and morphological characterization, the electrochemical behavior of lithium iron manganese phosphates has been compared to the one of pristine LiFePO4 and LiMnPO4, in order to evaluate the doping influence on the material.

This article was migrated. The article was marked as recommended. Introduction. The medical education literature lacks descriptions of evidence-based medicine (EBM) curricula with competency-based learning outcomes. The objective of this report is to describe an approach to designing, implementing, and assessing long-term learning in an integrated second-year EBM curriculum. Methods. Two complementary approaches were used. The primary deliberate approach incorporated large-group randomized controlled trial (RCT) critical appraisal sessions into existing organ system modules. The second approach added brief applications of EBM content to small-group case-based learning sessions. To assess learning, an open response written examination mapped to EBM competencies was administered at the beginning of the third year. Results. Data were available for 241 students. Using only walking knowledge, 47% of students at the beginning of the third year discussed two major weaknesses of an RCT; an additional 39% did so for only one. The ability to formulate a clinical question, describe elements of an appropriate search strategy and determine applicability to different patients was demonstrated by 84%, 87%, and 81% of examinees, respectively. Conclusion. This early work demonstrates that durable learning of EBM skills, including critical appraisal, is achievable among second-year medical students. Further work to improve learning in the second year and extend learning into subsequent years is forthcoming.

In 2014, the Association of American Medical Colleges identified 13 Core Entrustable Professional Activities for Entering Residency (Core EPAs), which are activities that entering residents might be expected to perform without direct supervision. This work included the creation of an interinstitutional concept group focused on faculty development efforts, as the processes and tools for teaching and assessing entrustability in undergraduate medical education (UME) are still evolving. In this article, the authors describe a conceptual framework for entrustment that they developed to better prepare all educators involved in entrustment decision making in UME. This framework applies to faculty with limited or longitudinal contact with medical students and to those who contribute to entrustment development or render summative entrustment decisions.The authors describe a shared mental model for entrustment that they developed, based on a critical synthesis of the EPA literature, to serve as a guide for UME faculty development efforts. This model includes four dimensions for Core EPA faculty development: (1) observation skills in authentic settings (workplace-based assessments), (2) coaching and feedback skills, (3) self-assessment and reflection skills, and (4) peer guidance skills developed through a community of practice. These dimensions form a conceptual foundation for meaningful faculty participation in entrustment decision making.The authors also differentiate between the UME learning environment and the graduate medical education learning environment to highlight distinct challenges and opportunities for faculty development in UME settings. They conclude with recommendations and research questions for future Core EPA faculty development efforts.

Background: Headache disorders are highly prevalent, and have a substantial and negative impact on health worldwide. They are largely treatable, but differences in structure, objectives, organization and delivery affect the quality of headache care. In order to recognize and remedy deficiencies in care, the Global Campaign against Headache, in collaboration with the European Headache Federation, recently developed a set of quality indicators for headache services. These require further assessment to demonstrate fitness for purpose. This is their first implementation to evaluate quality in headache care as a multicentre national study. Methods: Between September and December 2016, we applied the quality indicators in six Italian specialist headache centres (Bologna, Firenze, Modena, Padova, Roma Campus Bio-Medico and Roma Sapienza). We used five previously developed assessment instruments, translated into Italian according to Lifting The Burden’s translation protocol for hybrid documents. We took data from 360 consecutive patients (60 per centre) by questionnaire and from their medical records, and by different questionnaires from their health-care providers (HCPs), including physicians, nurses, psychologists and nursing assistants. Results: The findings, comparable between centres, confirmed the feasibility and practicability of using the quality indicators in Italian specialist headache centres. The questionnaires were easily understood by HCPs and patients, and were not unduly time-consuming. Diagnoses were almost all (> 97%) according to ICHD criteria, and routinely (100%) reviewed during follow-up. Diagnostic diaries were regularly used by 96% of physicians. Referral pathways from primary to specialist care existed in five of the six clinics, as did urgent referral pathways. Instruments to assess disability and quality of life were not used regularly, a deficiency that needs to be addressed. Conclusion: This Italy-wide survey confirmed in six specialist centres that the headache service quality indicators are fit for purpose. By establishing majority practice, identifying commonalities and detecting deficits as a guide to quality improvement, the quality indicators may be used to set benchmarks for quality assessment. The next step is extend use and evaluation of the indicators into non-specialist care. © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

The synthesis and characterization of a Mg Ni alloy having La and Ce as catalysts, have been performed. The alloy behavior was studied at given fixed temperature and pressure during hydrogen absorption/desorption tests. The La and Ce addition was carried out starting from a commercial alloy, named “Firesteel”. The alloy synthesized has the following formula Mg 68 Ni 26 M 5 X , where X represents Si and Fe impurities and M stands for the mixture of rare earths metals. The alloy has been prepared by a melting process in an induction furnace equipped with a centrifugal casting system and then grinded, by both hydraulic press and ball milling. The alloy has been characterized by SEM, BET, XRD, DSC-TGA analysis and by a mass flow measurement apparatus. The experiments on alloy sample showed that, after activation, hydrogenation occurs at 300 °C in three stages at three different pressures: 3, 4 and 7 atm, involving respectively 0.15 wt%, 0.4 wt% and 2.2 wt% of hydrogen absorbed. Reversible hydride dehydrogenation, inside the mass flow measurement apparatus, requires a working temperature of 350 °C to obtain, with remarkable reaction rate, about 2.7%, hydrogen desorption.

In this study Ni Co W alloys have been produced by electrodeposition on Al net. Two electrolytic baths, with and without sodium citrate, having the same metal ion content (20 g/l Ni, 8 g/l Co and W in the range 2–8 g/l) and boric acid content 20 g/l, have been used. Temperature and current density operative conditions have been varied in the range 30–60 °C and 260–350 A/m2 respectively. The electrodeposition performed in the presence of sodium citrate presents always the best results in term of current efficiency and specific energy consumption, while W content in the alloy highlights different behavior: W content increasing with temperature by using citrate in solution and quite constant W content with temperature, without citrate. Morphological and structural analyses of deposits have been also performed to assess the electrolysis conditions and to obtain the best deposit. Preliminary electrochemical tests have been also carried out on Ni Co W deposits for establishing their ability to act as cathode for HER and to compare these ternary alloys with Ni Co binary alloys, thus detecting W positive influence in both hydrogen overvoltage and exchange current density. The W presence in the alloys affects, in the same way, the HER independently of the used bath for their production.

The use of Ni-Ti alloys in the practice of endodontic comes from their important properties such as shape memory and superelasticity phenomena, good corrosion resistance and high compatibility with biological tissues. In the last twenty years a great variety of nickel-titanium rotary instruments, with various sections and taper, have been developed and marketed. Although they have many advantages and despite their increasing popularity, a major concern with the use of Ni-Ti rotary instruments is the possibility of unexpected failure in use due to several reasons: novice operator handling, presence manufacturing defects, fatigue etc. Recently, the use of an aqueous gel during experimental tests showed a longer duration of the instruments. The aim of the present work is to contribute to the study of the fracture behavior of these endodontic rotary instruments particularly assessing whether the use of the aqueous lubricant gel can extend their operative life stating its reasons. A finite element model (FEM) has been developed to support the experimental results. The results were rather contradictory, also because the Perspex (Poly-methyl methacrylate, PMMA) cannot simulate completely the dentin mechanical behavior; however the results highlight some interesting points which are discussed in the paper.

Indium can be recovered from the residues of zinc and lead refineries and from electronic scrap. In the hydrometallurgical processes the main problem is separating In(III) from Fe(III) that are both present in the leaching solutions. In this work the extraction of In(III) from HCl, H2SO4, and HNO3 media using D2EHPA, LIX 984, CYANEX 272 and IONQUEST 801 solutions in kerosene is investigated. In(III) is quantitatively extracted from every considered acidic solution by means of IONQUEST 801 even at quite low pH. D2EHPA allows to obtain extraction yields very similar to those obtainable by means of IONQUEST 801 except in the extraction tests from HCl solutions. The extraction behavior of some commonly associated metal ions such as Fe(III), Cu(II) and Zn(II), has also been investigated with the aim of attaining high extraction selectivity. The results highlighted that both D2EHPA and IONQUEST 801 do not allow a complete Fe(III)–In(III) separation, while In(III) can be effectively separated from Cu(II) and Zn(II). The results highlighted that an effective Fe(III)–In(III) separation can be performed in the stripping stage.

In this study Ni–Co alloys have been activated during hydrogen electrochemical production by adding Mo ions into the alkaline electrolyte. After dissolving different amounts of sodium molybdate in the Na(OH) electrolyte, Ni–Co alloys were used as cathodes for hydrogen evolution reaction. Afterwards a comparison between hydrogen overvoltage measured on Ni–Co alloys with and without in situ activation has been made. The in situ activation clearly shows an improvement of electrocatalytic properties of Ni–Co alloys for hydrogen evolution reaction. Depending on the alloy the best conditions are reached with different amounts of sodium molybdate in the electrolyte. The values of exchange current density for Ni–Co alloys without Mo, are an average of about 4.1 10 −6 A/cm 2 , while by using in situ activation, these values are about 3.5·10 −4 A/cm 2 . Therefore, exchange current density presents a value nearly one hundred-fold higher when molybdate ions are present in solution. Moreover, two Tafel slope values have been determined for HER on Ni–Co alloys with and without Mo in situ activation. Those Tafel slope values are different, so as their range of both overvoltage and current density, probably highlighting a different kinetic mechanism.

Sulfur/lithium battery performances are strictly related to the morphology and nanostructure of sulfur particles. In this work, a comparison of the morphological characteristics and electrochemical properties of electrodes based on colloidal sulfur (CS) obtained by means of traditional chemical precipitation from aqueous solution and via spinning disk reactor (SDR) has been performed. In particular, through the SDR technique and by using different fluid dynamic conditions, it was possible to obtain monodisperse and nanometricsulfurparticles with higher electrochemical performances when used as the cathodic active material in lithium batteries. Moreover, a method to produce core&ndash, shell nanoparticles with sulfur and titanium dioxide, starting from a colloidal sulfur (S8) solution and produced by SDR, has been performed, obtaining good electrochemical results. In particular, the nanometric sulfur powder produced by the SDR technique showed a capacity higher than CS after 100 cycles, even if the capacity decreased rapidly in both cases. Instead, considering the core&ndash, shell S&ndash, TiO2 material, the nanostructured electrode allowed a wide use of active material and a reduced capacity decay during cycling. Specifically, the material showed an initial capacity of 1395 mAh/g, i.e., representing 83% of the theoretical value, which decreased during operation up to 450 mAh/g after about 30 cycles. Then, the material capacity remained unchanged and no substantial loss of capacity was recorded up to 100th cycle.

OBJECTIVE To further the validity of a tool to assess nondirective pregnancy options counseling skills. METHODS Using a cross-sectional design, we explored four sources of construct validity evidence for an objective structured clinical examination for training and assessment of nondirective pregnancy options counseling: content, response process, internal structure, and relations to other variables. Content of the previously developed tool was enhanced through input from five family medicine educators. The objective structured clinical examination was implemented in a family medicine clerkship with third-year medical students from 2014 to 2015 using trained raters. Response process was addressed after a pilot round. Three new raters evaluated videotapes of 46 performances. Cronbach's alpha, intraclass correlation coefficients, and Spearman's rho were estimated with 95% confidence intervals. RESULTS The content validity was affirmed. Cronbach's alpha was 0.71. According to Landis and Koch's criteria, all but two items unique to the clinical situation of pregnancy options counseling generated substantial to perfect agreement (0.62-1.00). Relations to other variables within the checklist were strong, ranging from 0.66 to 0.87. DISCUSSION This tool for assessing pregnancy options counseling skills has excellent content and strong internal structure. Further work to improve the Global Rating Scale may be necessary for summative use.