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A series of semi-crystalline, wide band gap (WBG) photovoltaic polymers were synthesized with varying number and topology of fluorine substituents. To decrease intramolecular charge transfer and to modulate the resulting band gap of D-A type copolymers, electron-releasing alkoxy substituents were attached to electron-deficient benzothiadiazole (A) and electron-withdrawing fluorine atoms (0-4F) were substituted onto a 1,4-bis(thiophen-2-yl)benzene unit (D). Intra- and/or interchain noncovalent Coulombic interactions were also incorporated into the polymer backbone to promote planarity and crystalline intermolecular packing. The resulting optical band gap and the valence level were tuned to 1.93-2.15 eV and -5.37 to -5.67 eV, respectively, and strong interchain organization was observed by differential scanning calorimetry, high-resolution transmission electron microscopy and grazing incidence X-ray scattering measurements. The number of fluorine atoms and their position significantly influenced the photophysical, morphological and optoelectronic properties of bulk heterojunctions (BHJs) with these polymers. BHJ photovoltaic devices showed a high power conversion efficiency (PCE) of up to 9.8% with an open-circuit voltage of 0.94-1.03 V. To our knowledge, this PCE is one of the highest values for fullerene-based single BHJ devices with WBG polymers having a band gap of over 1.90 eV. A tandem solar cell was also demonstrated successfully to show a PCE of 10.3% by combining a diketopyrrolopyrrole-based low band gap polymer.

2D transition metal dichalcogenides (TMDs) for advanced logic transistor technologies are deposited by various modifications of the chemical vapor deposition (CVD) method using a wide variety of precursors. Being a major electrical performance limiter, the TMD crystal grain size strongly differs between the various CVD precursor chemistries from nano‐ to millimeter‐sized crystals. However, it remains unclear how the CVD precursor chemistry affects the nucleation density and resulting TMD crystal grain size. This work postulates guiding principles to design a CVD process for highly crystalline TMD deposition using a quantitative analytical model benchmarked against the literature. The TMD nucleation density reduces favorably under low supersaturation conditions where the metal precursor sorption on the starting surface is reversible and the corresponding metal precursor desorption rate exceeds the overall deposition rate. Such reversible precursor adsorption guarantees efficient long‐range gas‐phase lateral diffusion of precursor species in addition to short‐range surface diffusion, which vitally increases crystal grain size. The proposed model explains the large spread in experimentally observed TMD nucleation densities and crystal grain sizes for state‐of‐the‐art CVD chemistries. Ultimately, it empowers the reader to interpret and modulate precursor adsorption and diffusion reactions through designing CVD precursor chemistries. [ABSTRACT FROM AUTHOR]

While the power conversion efficiency (PCE) of organic photovoltaics (OPV) on small‐area lab cells has rapidly increased during the last few years, the performance on module level and the availability of OPV modules on the market is still limited, primarily due to specific constraints imposed by the industrial production process. This work deals with the upscaling process of latest‐generation OPV from small‐area lab cells to fully solution‐processed modules, which are compatible to industrial roll‐to‐roll (R2R) printing. This transfer is demonstrated step by step from material selection and process optimization for every single layer of the stack (photoactive layer, charge transporting layers, and solution‐processed top electrode)–including long‐term stability investigations (thermal and light)–to scaling up the device area by a factor of >100. Thus, a semitransparent OPV module with 10.8% PCE on 10.2 cm2 active area is achieved, which is among the highest performances for semitransparent, fully solution‐processed OPV modules. The individual developments all meet the requirements for industrial R2R printing (green solvents, processing in air, annealing ≤140 °C, etc.), which ensures that both the optimized layer stack and the fabrication process are fully scalable and easily transferable to large‐scale production. [ABSTRACT FROM AUTHOR]

Introduction: Compared to judokas (JU) and non-athletes (NA), horseback riders (HR) may develop specific changes in their sensory control of balance. Methods: Thirty-four international-level JU, twenty-seven international-level HR and twenty-one NA participated. Participants stood upright on a plateform (static condition) or on a seesaw device with an instability along the mediolateral (ML) or the anteroposterior (AP) direction (dynamic conditions). These conditions were carried out with eyes opened (EO) or closed (EC), and with (wF) or without a foam (nF). Experimental variables included conventional (linear), non-linear center-ofpressure (COP) parameters, Romberg Quotient (RQ) and Plantar Quotient (PQ). Results: Group effects. COP Surface (COPS) and standard deviation of COP along AP (SDY) were lower in HR than in JU in Static. SD Y was lower in HR than in JU in Dynamic AP. COP velocity (COPV) was lower in both HR and JU than in NA in Static and Dynamic. Sample entropy along AP and ML (SampEnY and SampEnX) were higher in HR than in JU in Static. SampEnY was higher in HR than in JU in Dynamic ML. Sensory effects. In EC, COPV was lower in JU than in NA in Dynamic AP, and lower in JU than in both HR and NA in Dynamic ML. In EO, COPV was lower in both JU and HR than in NA in Dynamic ML. RQ applied to COPS was lower in JU than in both HR and NA in Dynamic AP, and lower in JU than in HR in Dynamic ML. RQ applied to COPV was lower in JU than in both HR and NA in Static and Dynamic. PQ applied to COPS was higher in JU than in both HR and NA in Dynamic ML. Conclusion: Results showed that the effects of sport expertise on postural control could only be revealed with specific COP variables and were directionally oriented and sport-dependant. HR seem to rely more on vision than JU, thus revealing that the contribution of the sensory inputs to balance control is also sportdependent. Results open up new knowledge on the specificity of sport practice on multisensory balance information during upright posture. [ABSTRACT FROM AUTHOR]

The introduction of nonfullerene acceptors (NFAs) has pushed the power conversion efficiency and organic photovoltaics (OPV) device stability to new standards. In this aspect, removal of trace impurities from one purification stage to the next is frequently stressed throughout the synthesis of photoactive OPV materials and NFAs to obtain the highest‐purity material. However, detailed studies of the effect of purification on device performance are less reported. Herein, the role of NFA trace impurities on the optoelectronic characteristics and lifetime of resulting OPV devices is studied. The optimization of PBDB‐T:ITIC‐X devices, with various ITIC purity levels (X), has been thoroughly studied via a combination of photophysical, chemical, morphological, electrical, and optical characterization techniques, to shine light on the role of these impurities on device performance and lifetime. The findings suggest that, even in materials with larger concentrations of trace impurities, careful tuning can produce high efficiencies. Interestingly, the less‐pure materials lead to longer device lifetimes along with an enhancement in accumulative power generation by a factor 3, compared to the purest ITIC‐based devices. This demonstrates that selecting a material with the highest purity may not always be the best option for NFA OPV and that any positive effects of NFA purification must be carefully considered in light of both the device efficiency and stability. [ABSTRACT FROM AUTHOR]

During the past twenty years, an important body of research has examined the different impacts of deinstitutionalisation on the adaptation and quality of life of persons with intellectual disabilities. This empirical study was conducted with 136 persons with intellectual disabilities following the closure of the Hopital Saint-Julien (Quebec, Canada). Various questionnaires relating to adaptive and maladaptive behaviors, mental health problems, medication and to the relocation were completed. The measures were taken following the exit from institutions and subsequently after 27 months. Improvements are observed on adaptive and maladaptive behaviors, and on mental health. The relation between medication's evolution and the one noted for the maladaptive behaviors and mental health is examined. The relocation variable should be considered in future studies. (Contains 6 tables.)

Background: Anti‐K is an alloantibody stimulated in response to the KEL1 antigen and may cause hemolytic disease of the fetus and newborn (HDFN). Provision of KEL1 negative blood to females of child‐bearing potential was not our practice. We assessed the impact of our policy and assessed feasibility of a KEL1 negative transfusion policy. Study design and methods: This is a cohort study spanning Jan 1, 2007–Jun 30, 2017 in Hamilton, Canada. Data were obtained via our institution's transfusion database. Chart reviews of females age ≤45 with anti‐K were performed; data on RBC KEL1 phenotype were obtained from the blood supplier when needed to ascertain the cause of alloimmunization. Descriptive analysis of hospital KEL1 negative inventory demand and supply was performed. Results: From Jan 2007‐Jun 2017, 8.6% of all RBC units transfused were provided to females age ≤45. There were 111 females with detectable anti‐K. Median age at time of antibody detection was 34 years (interquartile range 27–40) and 28 of 111 (25.2%) patients may have been alloimmunized by transfusion. Of 49 pregnancies, seven had complications due to anti‐K. We estimated that our existing RBC inventory (with 16% units known to be KEL1 negative in 2017) is sufficient to meet demand and support a KEL1 negative transfusion policy for females age ≤45. Conclusion: Transfusion was responsible for alloimmunization in 25% of females with anti‐K over 10 years. Analysis of supply and demand can be used to inform feasibility of a KEL1 negative transfusion policy. [ABSTRACT FROM AUTHOR]

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This paper proposes a coherent risk measure to assess project cost overrun contingency reserves: the project expected cost overrun (ECO). It is shown that the traditional project cost-percentile metric does not qualify as a coherent risk measure and, therefore, that the ECO metric should be adopted. Obtained from the tail expectation of the project cost probability distribution, it measures the average value of project costs exceeding, at any significance level, the project cost baseline. A positive, unique, and exact closed-form solution to the ECO risk measure is devised under, among others, the normal probability distribution. The resulting project cost overrun contingency reserve may be interpreted as an insurance contract covering contingent risk factors and claimable by project managers from their project director once preidentified and agreed-upon contingent high-risk cost impacts are taken into account. The project ECO risk measure is extended to assess the project expected time overrun (ETO) and the project expected time overrun penalty (ETOP) risk measures, quantities that will prove indispensable for successfully tendering under any contractual form the minimum value of project time and project cost bids. They will be covering, at the very least, all relevant potential low-probability high-risk contingent risk factor impacts. [ABSTRACT FROM AUTHOR]

The present study reports the impact of process conditions and post annealing treatment on the stress and physico-chemical properties in different types of plasma enhanced atomic layer deposited (PEALD) SiNx films. More specifically, the SiNx films deposited at 500 °C were annealed subsequently at 1000 °C in N2 ambient for different times ranging between 30 and 6750 s and were subjected to thickness, mass, refractive index, chemical bonds and structure, H content, N/Si stoichiometry, morphology, roughness, and uniformity monitoring. Depending on the deposition process conditions, we confirm the possibility to form, at 500 °C with PEALD, some very compressive SiN films with reduced hydrogen content by controlling the plasma conditions along the deposition process. More interestingly, these compressive films with low hydrogen concentration exhibit high thermo-mechanical stability compared to hydrogenated PEALD and plasma enhanced chemical vapor deposition silicon nitride from this study or reported in the literature, films which typically tend to become tensile with a similar annealing sequence. These results confirm the importance of the plasma power to engineer the as-deposited silicon nitride stress but also highlight the role of hydrogen in the thermal instability of these layers, a low H concentration being needed for a better mechanical stability. [ABSTRACT FROM AUTHOR]

Background and Objectives: A high proportion of suspected weak D patients referred to Héma‐Québec were genotyped as weak D type 42 (368/2105, 17.5%). These patients are currently considered D with regard to RhD immunoprophylaxis in pregnancy and transfusion. The goal of this study was to retrospectively evaluate the risk of alloimmunization in weak D type 42 patients and to characterize their RhD surface molecule expression on red blood cells (RBCs) in comparison to other weak D types (1, 2 and 3). Materials and Methods: A retrospective analysis using the weak D type 42 patients' medical data to verify potential anti‐D alloimmunization events was conducted. Quantitative analyses using flow cytometry were also performed on RBCs to quantify the cell surface density of the D antigen. Results: Data on 215 subjects with weak D type 42 were reviewed. None developed immune allo‐anti‐D; three had definite exposure to D+ red cells and 41 had possible exposure through pregnancy. Flow cytometry analysis showed that weak D types 1, 2, 3 and 42 had relative antigen densities of 2.7%, 2.2%, 8.1% and 3.6%, respectively, with R1R2 red cells referencing 100% density. The estimated antigen density range of weak D type 42 was 819–1104 sites per RBC. Conclusion: Our retrospective alloimmunization data analysis and antigen density study establish a basis for the consideration of a weak D type 42 individual as D+. This consideration would allow for a targeted reduction of RhD immunoprophylaxis in pregnancy and the unjustified use of D– units for transfusion. [ABSTRACT FROM AUTHOR]

Cet article explique la facon dont les informations provenant de la cooperation internationale sur la prevention du terrorisme influencent le design des programmes de formation des agents de controle preembarquement a l'Administration canadienne de la surete du transport aerien (ACSTA). Il expose comment l'integration de ces informations a conduit au developpement d'une methodologie de formation qui suit les principes de la formation par competences. Cette reflexion marque le cinquieme anniversaire de la fondation de l'ACSTA et le sixieme des attentats du 11 septembre 2001. Les auteurs presentent les grands enjeux de la securite aeroportuaire, les contraintes et opportunites du contexte international, ainsi que les methodologies et strategies utilisees dans le programme de formation. This article describes how information provided by the international community influences the design of training programs for airport security officers at the Canadian Air Transport Security Authority (CATSA). It explains how the integration of this information was instrumental in selecting a training program that follows the principles of a competency-based methodology. This review coincides with the fourth anniversary of the creation of CATSA and the fifth of the tragedy of September 11th, 2001. The authors identify major airport security issues, opportunities and constraints dictated by the international context, and the main strategic and methodological alternatives., La plupart des attaques terroristes visent ou utilisent les transports. Le transport aerien en particulier est une cible privilegiee, car il permet de maximiser l'impact de l'action terroriste. Les terroristes [...]

Background: The efficacy of premedication for the prevention of nonhemolytic transfusion reactions remains controversial. This systematic review and meta-analysis assessed the effect of premedication on the rate of nonhemolytic transfusion reactions after allogeneic blood transfusion.Study Design and Methods: We searched the literature using CENTRAL, MEDLINE, EMBASE, ISI Web of Science, and clinicaltrials.gov databases from inception until October 31, 2018. We included all randomized controlled trials comparing premedication to placebo or no treatment in patients receiving any labile blood product. Outcome measures were reported as relative risks (RRs) with 95% confidence intervals (CIs). Data were combined for similar outcomes where appropriate using a random-effects model. Analyses were done at both the patient and transfusion level.Results: Three randomized trials using acetaminophen and antihistamine as premedication met the inclusion criteria. A total of 517 patients received 4444 red blood cell or platelet transfusions. Pooled patient-level estimates with premedication for all nonhemolytic, febrile nonhemolytic, and minor allergic reactions were RR, 0.92 (95% CI, 0.63-1.35); RR, 0.54 (95% CI, 0.26-1.1); and RR, 1.37 (95% CI 0.81-2.31), respectively. Transfusion-level analyses also showed no benefit with premedication. Of 517 patients randomized, only 27 (5.2%) had a history of transfusion reactions.Conclusion: Routine premedication with acetaminophen and antihistamines did not prevent nonhemolytic transfusion reactions; however, the estimate of effect was greatest for febrile reactions. The impact of premedication in patients with a prior history of transfusion reactions remains unknown and requires further evaluation in future clinical trials. [ABSTRACT FROM AUTHOR]

Silicon dioxide is used to electrically isolate CMOS devices such as fin field effect transistors by filling gaps between the devices (also known as shallow trench isolation). The gap fill oxide typically requires a high temperature anneal in excess of 1000 °C to achieve adequate electrical properties and oxide densification to make the oxide compatible with subsequent fabrication steps such as fin reveal etch. However, the transition from Si-based devices to high mobility channel materials such as SiGe and III-V semiconductors imposes more severe thermal limitations on the processes used for device fabrication, including gap fill oxide annealing. This study provides a framework to quantify and model the effect of anneal temperature and time on the densification of a flowable silicon dioxide as measured by wet etch rate. The experimental wet etch rates allowed the determination of the activation energy and anneal time dependence for oxide densification. Dopant and self-diffusion can degrade the channel material above a critical temperature. We present a model of self-diffusion of Ge and Si in SiGe materials. Together these data allowed us to map the thermal process space for acceptable oxide wet etch rate and self-diffusion. The methodology is also applicable to III-V devices, which require even lower thermal budget. The results highlight the need for nonthermal oxide densification methods such as ultraviolet (UV) and plasma treatments. We demonstrate that several plasma treatments, in place of high temperature annealing, improved the properties of flowable oxide. In addition, UV curing prior to thermal annealing enables acceptable densification with dramatically reduced anneal temperature. [ABSTRACT FROM AUTHOR]

The carbon fines (CF) carrying Klebsiella pneumoniae transfer the bacteria to heterotrophic biofilms, promoting the successful colonization of the coliform in the biofilm. Both K. pneumoniae and CF are detached and disinfected faster than the total population following chlorination. A limited population of coliforms and CFs resist chlorination and persist in the biofilm. Coliforms and other organisms that survive biological treatment act as inocula for the drinking water distribution system and attachment to CFs plays a role in the effectiveness of this process.