Precisely Controlling Polymer Acceptors with Weak Intramolecular Charge Transfer Effect and Superior Coplanarity for Efficient Indoor All-Polymer Solar Cells with over 27% Efficiency.

Indoor photovoltaics (IPVs) are garnering increasing attention from both the academic and industrial communities due to the pressing demand of the ecosystem of Internet-of-Things. All-polymer solar cells (all-PSCs), emerging as a sub-type of organic photovoltaics, with the merits of great film-forming properties, remarkable morphological and light stability, hold great promise to simultaneously achieve high efficiency and long-term operation in IPV's application. However, the dearth of polymer acceptors with medium-bandgap has impeded the rapid development of indoor all-PSCs. Herein, a highly efficient medium-bandgap polymer acceptor (PYFO-V) is reported through the synergistic effects of side chain engineering and linkage modulation and applied for indoor all-PSCs operation. As a result, the PM6:PYFO-V-based indoor all-PSC yields the highest efficiency of 27.1% under LED light condition, marking the highest value for reported binary indoor all-PSCs to date. More importantly, the blade-coated devices using non-halogenated solvent (o-xylene) maintain an efficiency of over 23%, demonstrating the potential for industry-scale fabrication. This work not only highlights the importance of fine-tuning intramolecular charge transfer effect and intrachain coplanarity in developing high-performance medium-bandgap polymer acceptors but also provides a highly efficient strategy for indoor all-PSC application.

Data Cleansing and Sub-Unit-Based Molecular Description Enable Accurate Prediction of The Energy Levels of Non-Fullerene Acceptors Used in Organic Solar Cells.

Non-fullerene acceptors (NFAs) have recently emerged as pivotal materials for enhancing the efficiency of organic solar cells (OSCs). To further advance OSC efficiency, precise control over the energy levels of NFAs is imperative, necessitating the development of a robust computational method for accurate energy level predictions. Unfortunately, conventional computational techniques often yield relatively large errors, typically ranging from 0.2 to 0.5 electronvolts (eV), when predicting energy levels. In this study, the authors present a novel method that not only expedites energy level predictions but also significantly improves accuracy , reducing the error margin to 0.06 eV. The method comprises two essential components. The first component involves data cleansing, which systematically eliminates problematic experimental data and thereby minimizes input data errors. The second component introduces a molecular description method based on the electronic properties of the sub-units comprising NFAs. The approach simplifies the intricacies of molecular computation and demonstrates markedly enhanced prediction performance compared to the conventional density functional theory (DFT) method. Our methodology will expedite research in the field of NFAs, serving as a catalyst for the development of similar computational approaches to address challenges in other areas of material science and molecular research.

Regio-Regular Polymer Acceptors Enabled by Determined Fluorination on End Groups for All-Polymer Solar Cells with 15.2 % Efficiency.

Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance of all-polymer solar cells (all-PSCs). Different from our recent work about fluoro- and bromo- co-modified end group of IC-FBr (a mixture of IC-FBr1 and IC-FBr2), in this paper, we synthesized and purified two regiospecific fluoro- and bromo- substituted end groups (IC-FBr-o & IC-FBr-m), which were then employed to construct two regio-regular polymer acceptors named PYF-T-o and PYF-T-m, respectively. In comparison with its isomeric counterparts named PYF-T-m with different conjugated coupling sites, PYF-T-o exhibits stronger and bathochromic absorption to achieve better photon harvesting. Meanwhile, PYF-T-o adopts more ordered inter-chain packing and suitable phase separation after blending with the donor polymer PM6, which resulted in suppressed charge recombination and efficient charge transport. Strikingly, we observed a dramatic performance difference between the two isomeric polymer acceptors PYF-T-o and PYF-T-m. While devices based on PM6:PYF-T-o can yield power conversion efficiency (PCE) of 15.2 %, devices based on PM6:PYF-T-m only show poor efficiencies of 1.4 %. This work demonstrates the success of configuration-unique fluorinated end groups in designing high-performance regular polymer acceptors, which provides guidelines towards developing all-PSCs with better efficiencies.

Intravenous Propofol Versus Volatile Anesthetics For Stroke Endovascular Thrombectomy.

BACKGROUND: The choice of anesthetic technique for ischemic stroke patients undergoing endovascular thrombectomy is controversial. Intravenous propofol and volatile inhalational general anesthetic agents have differing effects on cerebral hemodynamics, which may affect ischemic brain tissue and clinical outcome. We compared outcomes in patients undergoing endovascular thrombectomy with general anesthesia who were treated with propofol or volatile agents. METHODS: Consecutive endovascular thrombectomy patients treated using general anesthesia were identified from our prospective database. Baseline patient characteristics, anesthetic agent, and clinical outcomes were recorded. Functional independence at 3 months was defined as a modified Rankin Scale of 0 to 2. RESULTS: There were 313 patients (182 [58.1%] men; mean±SD age, 64.7±15.9 y; 257 [82%] anterior circulation), of whom 254 (81%) received volatile inhalational (desflurane or sevoflurane), and 59 (19%) received intravenous propofol general anesthesia. Patients with propofol anesthesia had more ischemic heart disease, higher baseline National Institutes of Health Stroke Scale scores, more basilar artery occlusion, and were less likely to be treated with intravenous thrombolysis. Multivariable logistic regression analysis showed that propofol anesthesia was associated with improved functional independence at 3 months (odds ratio=2.65; 95% confidence interval, 1.14-6.22; P=0.03) and a nonsignificant trend toward reduced 3-month mortality (odds ratio=0.37; 95% CI, 0.12-1.10; P=0.07). CONCLUSION: In stroke patients undergoing endovascular thrombectomy treated using general anesthesia, there may be a differential effect between intravenous propofol and volatile inhalational agents. These results should be considered hypothesis-generating and be tested in future randomized controlled trials.

Random Polymerization Strategy Leads to a Family of Donor Polymers Enabling Well-Controlled Morphology and Multiple Cases of High-Performance Organic Solar Cells.

Developing high-performance donor polymers is important for nonfullerene organic solar cells (NF-OSCs), as state-of-the-art nonfullerene acceptors can only perform well if they are coupled with a matching donor with suitable energy levels. However, there are very limited choices of donor polymers for NF-OSCs, and the most commonly used ones are polymers named PM6 and PM7, which suffer from several problems. First, the performance of these polymers (particularly PM7) relies on precise control of their molecular weights. Also, their optimal morphology is extremely sensitive to any structural modification. In this work, a family of donor polymers is developed based on a random polymerization strategy. These polymers can achieve well-controlled morphology and high-performance with a variety of chemical structures and molecular weights. The polymer donors are D-A1-D-A2-type random copolymers in which the D and A1 units are monomers originating from PM6 or PM7, while the A2 unit comprises an electron-deficient core flanked by two thiophene rings with branched alkyl chains. Consequently, multiple cases of highly efficient NF-OSCs are achieved with efficiencies between 16.0% and 17.1%. As the electron-deficient cores can be changed to many other structural units, the strategy can easily expand the choices of high-performance donor polymers for NF-OSCs.

Migraine Aura: Updates in Pathophysiology and Management.

PURPOSE OF REVIEW: To provide an updated review of the pathophysiology, diagnosis, and management of migraine with aura. RECENT FINDINGS: Thalamic and other subcortical regions may play a role in the pathophysiology of migraine. There is inter-patient and intra-patient attack variability in the characteristics of typical aura especially visual aura symptoms. Migraine with brainstem aura may originate cortically. Migraine with retinal aura may be associated with structural and functional changes in the retina. Although cortical spreading depression (CSD) continues to be the predominant theory surrounding the pathophysiology of migraine with aura, the exact mechanism of action of CSD and its role in relation of all phases of migraine including features of aura are not fully understood. Novel experimental models and newer diagnostic tools including neuroimaging are currently being used to enhance of understanding of migraine with and without aura. Transient ischemia attacks, stroke, and epilepsy should be considered in your differential diagnosis of migraine with aura. There are no specific therapies for migraine with aura.

Prediction of idiopathic pulmonary fibrosis progression using early quantitative changes on CT imaging for a short term of clinical 18-24-month follow-ups.

OBJECTIVE: High-resolution computed tomography (HRCT) plays an indispensable role in the diagnosis of idiopathic pulmonary fibrosis (IPF). Due to unpredictability in progression and the short median survival of 2-5 years, it is critical to delineate the patients with rapid progression. The aim is to evaluate the predictability of IPF progression using the early quantitative changes. METHODS: Automated texture-based quantitative lung fibrosis (QLF) was calculated from the anonymized HRCT. Two datasets were collected retrospectively: (1) a pilot study of 35 subjects with three sequential scans (baseline and 6 and 12 months) to obtain a threshold, where visual assessments were stable at 6 months but worsened at 12 months; (2) 157 independent subjects to test the threshold. Landmark Cox regressions were used to compare the progression-free survival (PFS) defined by pulmonary function using the threshold from the early changes in QLF. C-indexes were reported as estimations of the concordance of prediction. RESULTS: A threshold of 4% QLF change at 6 months corresponded to the mean change that worsened on HRCT visually at 12 months from the pilot study. Using the threshold, significant differences were found in the independent dataset (hazard ratio (HZ) = 5.92, p = 0.001 by Cox model, C-index = 0.71 at the most severe lobe; and HZ = 3.22, p = 0.012, C-index = 0.68 in the whole lung). Median PFS was 11.9 months for subjects with ≥ 4% changes, whereas median PFS was greater than 18 months for subjects with < 4% changes at the most severe lobe. CONCLUSION: Early structural changes on HRCT using a quantitative score can predict progression in lung function. KEY POINTS: • Changes on HRCT using quantitative texture-based scores can play a pivotal role for providing information and an aid tool for timely management decision for patients with IPF. • Quantitative changes on HRCT of 4% or more, which matched 6-month prior changes with visual assessment of worsening, can play a pivotal role for providing prediction of clinical progression by 3-5 folds higher in the next incidence, compared with those of subjects with less than 4% changes. • Early structural changes of 4% or more in a paired HRCT scans derived by quantitative scores can predict the progression in lung function in 1-2 years in subjects with IPF, which is critical information for timely management decision for subjects with IPF where the median survival is 2 to 5 years.

Updates in the Treatment of Post-Stroke Pain.

PURPOSE OF REVIEW: To provide an overview of the current treatment strategies for common subtypes of post-stroke pain. RECENT FINDINGS: There is growing research interest in non-pharmacological treatment approaches for chronic pain, including neurostimulation as well as lifestyle and psychosocial interventions. Newer pharmacotherapy research includes cannabinoids and NMDA-receptor antagonists as well as bee venom. Persistent post-stroke headache is an increasingly appreciated entity, though the role of novel chronic migraine treatments for post-stroke headache is not known. Overall, most treatment approaches to post-stroke pain lack high-quality evidence. Stroke survivors are in need of effective treatments based on methodologically sound evidence. To address the interplay of clinical and psychosocial factors that contribute to post-stroke pain, it may be reasonable to adopt a multimodal treatment strategy incorporating both lifestyle interventions and conventional therapies.

A Narrative Review of Persistent Post-Stroke Headache - A New Entry in the International Classification of Headache Disorders, 3rd Edition.

BACKGROUND: Persistent post-stroke headache is a clinical entity that has recently entered the International Classification of Headache Disorders, 3rd edition. In contrast to acute headache attributed to stroke, the epidemiology, clinical features, potential pathophysiology, and management of persistent post-stroke headache have not been reviewed. METHODS: We summarize the literature describing persistent headache attributed to stroke. RESULTS: Persistent headache after ischemic or hemorrhagic stroke affects up to 23% of patients. These persistent headaches tend to have tension-type features and are more frequent and severe than acute stroke-related headaches. Risk factors include younger age, female sex, pre-existing headache disorder, and comorbid post-stroke fatigue or depression. Other factors including obstructive sleep apnea or musculoskeletal imbalances may contribute to headache persistence. Although more evidence is needed, it may be reasonable to treat persistent post-stroke headache according to headache semiology. CONCLUSION: Recognition of persistent post-stroke headache as a separate clinical entity from acute stroke-attributed headache is the first step toward better defining its natural history and most effective treatment strategies.

Quantitative relations between interaction parameter, miscibility and function in organic solar cells.

Although it is known that molecular interactions govern morphology formation and purity of mixed domains of conjugated polymer donors and small-molecule acceptors, and thus largely control the achievable performance of organic solar cells, quantifying interaction-function relations has remained elusive. Here, we first determine the temperature-dependent effective amorphous-amorphous interaction parameter, χaa(T), by mapping out the phase diagram of a model amorphous polymer:fullerene material system. We then establish a quantitative 'constant-kink-saturation' relation between χaa and the fill factor in organic solar cells that is verified in detail in a model system and delineated across numerous high- and low-performing materials systems, including fullerene and non-fullerene acceptors. Our experimental and computational data reveal that a high fill factor is obtained only when χaa is large enough to lead to strong phase separation. Our work outlines a basis for using various miscibility tests and future simulation methods that will significantly reduce or eliminate trial-and-error approaches to material synthesis and device fabrication of functional semiconducting blends and organic blends in general.

Reversible Parkinsonism and Rapidly Progressive Dementia Due to Dural Arteriovenous Fistula: Case Series and Literature Review.

BACKGROUND: Dural arteriovenous fistula (dAVF) rarely presents with a syndrome of reversible parkinsonism and rapidly progressive dementia, which has been described in 19 patients to date. However, its presenting features, pathophysiology, and response to treatment have not been reviewed. METHODS: We report the clinical course and treatment of two novel patients with this syndrome. RESULTS: Despite severe presentations, both patients recovered fully after fistula obliteration. CONCLUSIONS: Atypical parkinsonism with early cognitive changes and other focal neurological signs, along with features such as pulsatile tinnitus or worsening headache, should raise the possibility of dAVF. When treated, this syndrome is nearly always reversible, highlighting the importance of early diagnosis.

Donor polymer design enables efficient non-fullerene organic solar cells.

To achieve efficient organic solar cells, the design of suitable donor-acceptor couples is crucially important. State-of-the-art donor polymers used in fullerene cells may not perform well when they are combined with non-fullerene acceptors, thus new donor polymers need to be developed. Here we report non-fullerene organic solar cells with efficiencies up to 10.9%, enabled by a novel donor polymer that exhibits strong temperature-dependent aggregation but with intentionally reduced polymer crystallinity due to the introduction of a less symmetric monomer unit. Our comparative study shows that an analogue polymer with a C2 symmetric monomer unit yields highly crystalline polymer films but less efficient non-fullerene cells. Based on a monomer with a mirror symmetry, our best donor polymer exhibits reduced crystallinity, yet such a polymer matches better with small molecular acceptors. This study provides important insights to the design of donor polymers for non-fullerene organic solar cells.

Reduced Intramolecular Twisting Improves the Performance of 3D Molecular Acceptors in Non-Fullerene Organic Solar Cells.

A small-molecular acceptor, tetraphenylpyrazine-perylenediimide tetramer (TPPz-PDI4 ), which has a reduced extent of intramolecular twisting compared to two other small-molecular acceptors is designed. Benefiting from the lowest extent of intramolecular twisting, TPPz-PDI4 exhibits the highest aggregation tendency and electron mobility, and therefore achieves a highest power conversion efficiency of 7.1%.

High-Performance Non-Fullerene Polymer Solar Cells Based on a Pair of Donor-Acceptor Materials with Complementary Absorption Properties.

A 7.3% efficiency non-fullerene polymer solar cell is realized by combining a large-bandgap polymer PffT2-FTAZ-2DT with a small-bandgap acceptor IEIC. The complementary absorption of donor polymer and small-molecule acceptor is responsible for the high-performance of the solar-cell device. This work provides important guidance to improve the performance of non-fullerene polymer solar cells.

A tetraphenylethylene core-based 3D structure small molecular acceptor enabling efficient non-fullerene organic solar cells.

A tetraphenylethylene core-based small molecular acceptor with a unique 3D molecular structure is developed. Bulk-heterojunction blend films with a small feature size (≈20 nm) are obtained, which lead to non-fullerene organic solar cells (OSCs) with 5.5% power conversion efficiency. The work provides a new molecular design approach to efficient non-fullerene OSCs based on 3D-structured small-molecule acceptors.

Healthy young minds: the effects of a 1-hour classroom workshop on mental illness stigma in high school students.

This study aimed to test the effects of a 1-h classroom-based workshop, led by medical students, on mental illness stigma amongst secondary school students. Students (aged 14-17) from three public secondary schools in British Columbia participated in the workshop. A questionnaire measuring stigma (including stereotype endorsement and desire for social distance) was administered immediately before (T1), immediately after (T2), and 1-month after the workshop (T3). A total of 279 students met the study inclusion criteria. Total scores on the stigma scale decreased by 23 % between T1 and T2 (p < 0.01). This was sustained 1-month post-workshop with a 21 % stigma reduction compared to pre-intervention (p < 0.01). This effect was primarily due to improvements in scores that measured desire for social distance. There were no significant changes in scores that measured stereotype endorsement. Adolescents' stigmatizing attitudes can be effectively reduced through a 1-h easily implementable and cost-effective classroom-based workshop led by medical students.

Neuroanatomic correlates of the feature-salience hierarchy in face processing: an fMRI -adaptation study.

Previous fMRI studies suggest that faces are represented holistically in human face processing regions. On the other hand, behavioral studies have also shown that some facial features are more salient than others for face recognition: the neural basis of this feature-salience hierarchy is not known. We used fMRI-adaptation together with a behavioral discrimination task and an ideal observer analysis to ask (1) whether different face parts contribute different amounts to the neural signal in face responsive regions, and (2) whether this response correlates more with the behavioral performance of human subjects or with the physical properties of the face stimuli. Twenty-three subjects performed a same/different discrimination experiment to characterize their ability to detect changes to different face parts. The same subjects underwent an fMRI-adaptation study, in which limited portions of the faces were repeated or changed between alternating stimuli. The behavioral study showed high efficiency in identity discrimination when the whole face, top half, or eyes changed, and low efficiency when the bottom half, nose, or mouth changed. During fMRI, there was a release of adaptation in the right and left fusiform face area (FFA) with changes to the whole face, top face-half, or the eyes. Changes to the bottom half, nose or mouth did not result in a significant release of adaptation in the right FFA, although bottom-half changes resulted in a release of adaptation in the left FFA. Adaptation in the right and left FFA and the right pSTS was correlated with human perceptual efficiency but not with ideal observer measures of the physical image differences between face parts. The feature-salience hierarchy of human face perception is therefore reflected in the activity in the right and left FFA and right pSTS, further supporting the key role of these structures in our perceptual experience of faces.

An ingestible wireless capsule for treatment of obesity.

Intragastric balloon has become a popular method for treatment of obesity due to its less-invasive and non-pharmaceutical procedure. In this method, a gas (or liquid)-filled balloon is inserted into the stomach using endoscopy or surgery. The balloon stays in and partially fills the stomach for a desired period of time to induce the feeling of satiety in the patient. At the end of the treatment period, the balloon is removed from the body using endoscopy or surgery. Although proven effective in treatment of obesity, this method suffers from several drawbacks. Requiring an endoscopic procedure or surgery to insert and exert the balloon from the stomach is the most important disadvantage of this method. These procedures are usually costly and may cause the patient to feel uncomfortable. Here, we propose a non-invasive method to overcome these drawbacks. In this method, an intragastric balloon is introduced into the body using an ingestible capsule. The volume of the capsule can be adjusted wirelessly after being swallowed by the patient. Using this method, a non-invasive and patient-specific treatment is possible.