Arabic translation and cross-cultural adaptation of the Sport Concussion Assessment Tool 5 (SCAT5)

The aim was to create a Modern Standard Arabic SCAT5 version for different Arabic dialects. This translation and cross-cultural adaptation was performed in eight stages: initial translations, reconciliation of translations and cultural adaptation, back translation, appraisal of back translations, validation of the translation, review and adjustment by reconciliation committee, pretesting in 12 football players and document finalisation. As an alternative to the problematic Months In Reverse Order Test (MIROT) in Arabic, the Serial 3s test (32 Arabic and 30 English participants), the Days of the Week Backwards test (DWBT), and the 'Adding Serial 3s' test were tested (30 English and 30 Arabic participants) for accuracy, difficulty and time of completion. The Arabic SCAT5 was similar and comparable to the original English version (7-point Likert scales =< 2). Testing of the pre-final version of the Arabic SCAT5 took 20.4 (SD 3.4) and 17.7 (SD 3.0) minutes respectively to complete and was found acceptable in terms of clarity, understandability, grammatical correctness and coherence. The Arabic Serial 3s test (subtraction version) was unsuitable due to high completion time, low pass rate and high difficulty perception [time = 47.2 (SD 28.0) s; accuracy = 55.2%; difficulty = 3.2 (SD 1.1)]. The Arabic DWBT was too fast and undemanding for concentration testing [time = 4.6 (SD 1.5) s; accuracy = 90%; difficulty = 1.1 (SD 0.3)]. The Adding Serial 3s tests produced similar completion times [18.4 (SD 6.8) vs. 21.1 (SD 5.3), p = 0.088], accuracy (100%) and self-rated difficulty [English = 2.0 (SD 0.7) vs. Arabic-speaking participants = 2.1 (SD 0.8), p = 0.512] and was therefore adopted to replace the MIROT. This culturally adapted Arabic-SCAT5 questionnaire is the first concussion assessment tool available for Arabic-speaking healthcare providers and athletes.https://www.termedia.pl/Journal/Biology_of_Sport-78hj2021Sports Medicin

Tuning Open-Circuit Voltage in Organic Solar Cells with Molecular Orientation

The role of molecular orientation of a polar conjugated polymer in polymer–fullerene organic photovoltaic (OPV) cells is investigated. A planar heterojunction (PHJ) OPV cell composed of poly­(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) is used as a model system to isolate the effect of the interfacial orientation on the photovoltaic properties. The molecular orientation of the aggregate P3HT relative to the PCBM layer is varied from highly edge-on (conjugated ring plane perpendicular to the interface plane) to appreciably face-on (ring plane parallel to the interface). It is found that as the P3HT stacking becomes more face-on there is a positive correlation to the OPV open-circuit voltage (<i>V</i>_OC), attributed to a shift in the highest occupied molecular orbital (HOMO) energy level of P3HT. In addition, the PHJ OPV cell with a broad P3HT stacking orientation distribution has a <i>V</i>_OC comparable to an archetypal bulk heterojunction (BHJ) device. These results suggest that, in the BHJ OPV cell, the hole energy level in the charge transfer state is defined in part by the orientation distribution of the P3HT at the interface with PCBM. Finally, the photoresponses of the devices are also shown to have a dependence on P3HT stacking orientation

Anisotropic Elastic Modulus of Oriented Regioregular Poly(3-hexylthiophene) Films

Specific morphological features of polymer semiconductors are often promoted in devices to optimize optoelectronic behavior. Less studied is the role of morphology on the mechanical properties of the film, such as elastic modulus, which is an important property for the development of flexible and stretchable devices. To gain insight into the morphological origin of elasticity in polymer semiconductors and its relationship to charge transport, we study the anisotropic in-plane elastic modulus of strain-aligned regioregular poly­(3-hexylthiophene) (P3HT) films and compare the results to previously measured field effect charge mobility. The film morphology is varied through the amount of applied strain and post strain thermal annealing. Morphological characterization includes UV–vis optical spectroscopy and X-ray diffraction. The elastic modulus is measured using a buckling-based measurement technique. The elastic modulus of the film is found to decrease as the film is plastically strained. Thermally annealing the strained films results in a large in-plane elastic modulus anisotropy, where the modulus increases in the direction of backbone alignment and decreases in the transverse direction. The measured elastic modulus is compared to the film morphology, showing a dependence on both in-plane polymer chain alignment and local aggregate order. Comparing the elastic modulus to field effect mobility shows that they are not necessarily correlated, which has important implication for flexible organic electronic device design

Efficient thick-film polymer solar cells with enhanced fill factors via increased fullerene loading

Developing effective methods to make efficient bulk-heterojunction polymer solar cells at roll-to-roll relevant active layer thickness is of significant importance. We investigate the effect of fullerene content in polymer:fullerene blends on the fill factor (FF) and on the performance of thick-film solar cells for four different donor polymers PTB7-Th, PDPP-TPT, BDT-FBT-2T, and poly[5,5′-bis(2-butyloctyl)-(2,2′-bithiophene)-4,4′-dicarboxylate-alt-5,5′-2,2′-bithiophene] (PDCBT). At a few hundreds of nanometers thickness, increased FFs are observed in all cases and improved overall device performances are obtained except for PDCBT upon increasing fullerene content in blend films. This fullerene content effect was studied in more detail by electrical and morphological characterization. The results suggest enhanced electron mobility and suppressed bimolecular recombination upon increasing fullerene content in thick polymer:fullerene blend films, which are the result of larger fullerene aggregates and improved interconnectivity of the fullerene phases that provide continuous percolating pathways for electron transport in thick films. These findings are important because an effective and straightforward method that enables fabricating efficient thick-film polymer solar cells is desirable for large-scale manufacturing via roll-to-roll processing and for multijunction devices

Efficient thick-film polymer solar cells with enhanced fill factors via increased fullerene loading

\u3cp\u3eDeveloping effective methods to make efficient bulk-heterojunction polymer solar cells at roll-to-roll relevant active layer thickness is of significant importance. We investigate the effect of fullerene content in polymer:fullerene blends on the fill factor (FF) and on the performance of thick-film solar cells for four different donor polymers PTB7-Th, PDPP-TPT, BDT-FBT-2T, and poly[5,5′-bis(2-butyloctyl)-(2,2′-bithiophene)-4,4′-dicarboxylate-alt-5,5′-2,2′-bithiophene] (PDCBT). At a few hundreds of nanometers thickness, increased FFs are observed in all cases and improved overall device performances are obtained except for PDCBT upon increasing fullerene content in blend films. This fullerene content effect was studied in more detail by electrical and morphological characterization. The results suggest enhanced electron mobility and suppressed bimolecular recombination upon increasing fullerene content in thick polymer:fullerene blend films, which are the result of larger fullerene aggregates and improved interconnectivity of the fullerene phases that provide continuous percolating pathways for electron transport in thick films. These findings are important because an effective and straightforward method that enables fabricating efficient thick-film polymer solar cells is desirable for large-scale manufacturing via roll-to-roll processing and for multijunction devices.\u3c/p\u3