75 research outputs found

    Acetal- and Aldehyde-Substituted Thiophene-Benzodithiophene Copolymers for Organic Solar Cells

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    This study introduces two wide bandgap polymers, PBDTAT and PBDTFT, designed for cost-effective organic solar cells (OSCs). PBDTAT, synthesized through Stille coupling polymerization, features a 3-acetal-substituted thiophene building block, while PBDTFT, with the 3-formyl-substituted thiophene building block, is derived through a simple postpolymerization acetal-to-formyl conversion. The acetal substituents induce significant twisting in the polymer backbone, reducing the highest occupied molecular orbital energy (EHOMO) of PBDTAT to −5.55 eV. Conversely, formyl groups have less steric impact, resulting in a more coplanar polymer backbone, and a strong electron-withdrawing effect, significantly lowering the EHOMO of PBDTFT to −5.67 eV. These lowered EHOMO levels contribute to achieving higher open-circuit voltages (VOC) of 0.77 and 0.84 V for OSC devices with active layers of PBDTAT:Y6 and PBDTFT:Y6, respectively. Surprisingly, space-charge-limited current hole mobilities of PBDTAT, in neat and blend films with Y6, demonstrate similar or higher mobilities than those of PBDTFT, challenging assumptions about the impact of a significantly twisted backbone in PBDTAT on hole transport. This suggests that introducing controlled backbone twisting could strategically broaden the bandgap and reduce the HOMO energy level without compromising charge transport. Consequently, the OSC devices based on PBDTAT:Y6 can achieve a short-circuit current density (JSC) of 24.00 mA/cm2. Furthermore, photoluminescence quenching experiments confirm highly efficient hole transfer from the PBDTFT/Y6 interface, despite the small EHOMO offset of only 0.07 eV. This leads to a high JSC of up to 24.20 mA/cm2 for the PBDTFT:Y6-based devices

    Data_Sheet_2_Risk prediction models for postoperative delirium in elderly patients with hip fracture: a systematic review.docx

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    ObjectivesTo systematically evaluate the risk prediction models for postoperative delirium in older adult hip fracture patients.MethodsRisk prediction models for postoperative delirium in older adult hip fracture patients were collected from the Cochrane Library, PubMed, Web of Science, and Ovid via the internet, covering studies from the establishment of the databases to March 15, 2023. Two researchers independently screened the literature, extracted data, and used Stata 13.0 for meta-analysis of predictive factors and the Prediction Model Risk of Bias Assessment Tool (PROBAST) to evaluate the risk prediction models for postoperative delirium in older adult hip fracture patients, evaluated the predictive performance.ResultsThis analysis included eight studies. Six studies used internal validation to assess the predictive models, while one combined both internal and external validation. The Area Under Curve (AUC) for the models ranged from 0.67 to 0.79. The most common predictors were preoperative dementia or dementia history (OR = 3.123, 95% CI 2.108–4.626, p ConclusionResearch on the risk prediction models for postoperative delirium in older adult hip fracture patients is still in the developmental stage. The predictive performance of some of the established models achieve expectation and the applicable risk of all models is low, but there are also problems such as high risk of bias and lack of external validation. Medical professionals should select existing models and validate and optimize them with large samples from multiple centers according to their actual situation. It is more recommended to carry out a large sample of prospective studies to build prediction models.Systematic review registrationThe protocol for this systematic review was published in the International Prospective Register of Systematic Reviews (PROSPERO) under the registered number CRD42022365258.</p

    Data_Sheet_1_Risk prediction models for postoperative delirium in elderly patients with hip fracture: a systematic review.docx

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    ObjectivesTo systematically evaluate the risk prediction models for postoperative delirium in older adult hip fracture patients.MethodsRisk prediction models for postoperative delirium in older adult hip fracture patients were collected from the Cochrane Library, PubMed, Web of Science, and Ovid via the internet, covering studies from the establishment of the databases to March 15, 2023. Two researchers independently screened the literature, extracted data, and used Stata 13.0 for meta-analysis of predictive factors and the Prediction Model Risk of Bias Assessment Tool (PROBAST) to evaluate the risk prediction models for postoperative delirium in older adult hip fracture patients, evaluated the predictive performance.ResultsThis analysis included eight studies. Six studies used internal validation to assess the predictive models, while one combined both internal and external validation. The Area Under Curve (AUC) for the models ranged from 0.67 to 0.79. The most common predictors were preoperative dementia or dementia history (OR = 3.123, 95% CI 2.108–4.626, p ConclusionResearch on the risk prediction models for postoperative delirium in older adult hip fracture patients is still in the developmental stage. The predictive performance of some of the established models achieve expectation and the applicable risk of all models is low, but there are also problems such as high risk of bias and lack of external validation. Medical professionals should select existing models and validate and optimize them with large samples from multiple centers according to their actual situation. It is more recommended to carry out a large sample of prospective studies to build prediction models.Systematic review registrationThe protocol for this systematic review was published in the International Prospective Register of Systematic Reviews (PROSPERO) under the registered number CRD42022365258.</p

    Table_1_Preoperative plasma visfatin may have a dual effect on the occurrence of postoperative delirium.docx

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    BackgroundVisfatin is considered to be a “novel pro-inflammatory cytokine.” Neuroinflammatory response is one of the important mechanisms of postoperative delirium (POD). The relationship between preoperative plasma visfatin and POD is unclear.ObjectiveTo investigate the relationship between preoperative plasma visfatin concentrations and POD (primary outcome) in older hip fracture patients and to explore whether it affects POD through inflammatory factors.Materials and methodsThis prospective cohort study enrolled 176 elderly patients who were scheduled for hip fracture surgery. Preoperative plasma was collected on the morning of surgery, and visfatin levels were measured. Interleukin (IL)-1 and IL-6 were measured using patients’ plasma collected on the first day after surgery. We used the 3-min diagnostic interview for Confusion Assessment Method-defined delirium (3D-CAM) twice daily within the 2 days after surgery to assess whether POD had occurred. Restricted cubic splines and piecewise regression were used to explore the relationship between preoperative plasma visfatin concentrations and POD, and further mediation analysis was used to verify whether visfatin plays a role in POD through regulating inflammatory factors.ResultsThe incidence of POD was 18.2%. A J-shaped association was observed between preoperative plasma visfatin levels and POD. The risk of POD decreased within the lower visfatin concentration range up to 37.87 ng/ml, with a hazard ratio of 0.59 per 5 ng/ml [odds ratio (OR) = 0.59, 95% confidence interval (CI) = 0.37–0.95], but the risk increased above this concentration (P for non-linearity ConclusionVisfatin is the protective factor in POD when the preoperative plasma visfatin concentration is below 37.87 ng/ml, but when it exceeds 37.87 ng/ml, the visfatin concentration is a risk factor for POD, which is mediated by postoperative plasma IL-6. The results suggest that preoperative visfatin may have a dual effect on the POD occurrence.Clinical trial registration[www.ClinicalTrials.gov], identifier [ChiCTR21 00052674].</p

    A Stable Blue Photosensitizer for Color Palette of Dye-Sensitized Solar Cells Reaching 12.6% Efficiency

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    We report a blue dye, coded as R6, which features a polycyclic aromatic hydrocarbon, 9,19-dihydro­benzo­[1â€Č,10â€Č]­phenanthro­[3â€Č,4â€Č:4,5]­thieno­[3,2-<i>b</i>]­benzo­[1,10]­phenanthro­[3,4-<i>d</i>]­thiophene, coupled with a diaryl­amine electron donor and 4-(7-ethynyl­benzo­[<i>c</i>]­[1,2,5]­thia­diazol-4-yl)­benzoic acid acceptor. Dye R6 displays a brilliant sapphire color in a sensitized TiO<sub>2</sub> mesoporous film with a Co­(II/III) tris­(bipyridyl)-based redox electrolyte. The R6 based dye-sensitized solar cell achieves an impressive power conversion efficiency of 12.6% under standard air mass 1.5 global, 100 mW cm<sup>–2</sup>, and shows a remarkable photostability

    Association of γΎ T Cell Compartment Size to Disease Activity and Response to Therapy in SLE

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    <div><p>Objective</p><p>Although γΎT cells are widely recognized as pivotal elements in immune-mediated diseases, their role in the pathogenesis of SLE and therapeutic outcome remains under explored. The current study aims to characterize the γΎT cell compartment in SLE and correlate its status to disease severity and response to therapy.</p><p>Methods</p><p>Human peripheral blood-derived γΎ T cells were isolated from 14 healthy volunteers and 22 SLE patients (before and after 4 and 12 weeks following the onset of glucocorticoids (GC), mycophenolatemofetil (MMF) orhydroxychloroquine (HCQ) treatment). The γΎ T cells were characterized using flow cytometry. In addition, serum concentration of IFN-Îł, TNF-α, IL-2, IL-4, IL-6, IL-10 and IL-17A was determined by cytometric bead array (CBA).</p><p>Results</p><p>The SLEDAI scores dropped significantly following therapy in a subset of patients (responders–R) but not in some (non- responders–NR). Peripheral blood γΎ T cells in general, and Îł9<sup>+</sup>ÎŽ T cells and TNF-α/IL-17-secreting CD4<sup>-</sup>CD8<sup>-</sup>γΎ T cell subsets in particular, were decreased in SLE compared to healthy controls. The numbers of the γΎ T cell subsets reached levels similar to those of healthy controls following therapy in R but not in NR. Serum IL-6, IL-10 and IL-17 but not IFN-Îł and TNF-α were significantly increased in SLE compared to the healthy controls and exhibited differential changes following therapy. In addition, inverse correlation was observed between SLEDAI scores and γΎ T cell compartments, especially with TNF-α<sup>+</sup>γΎT cells, TNF-α<sup>+</sup>Îł9+ÎŽT cells and IL17<sup>+</sup>CD4<sup>-</sup>CD8<sup>-</sup>γΎT cells subsets. Differential correlation patterns were also observed between serum cytokine levels and various γΎ T cell compartments.</p><p>Conclusions</p><p>A strong association exists between γΎ T cell compartments and SLE pathogenesis, disease severity and response to therapy.</p></div

    Enantioselective [4 + 1] Annulation Reactions of α‑Substituted Ammonium Ylides To Construct Spirocyclic Oxindoles

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    Ammonium ylides have a long history in organic synthesis, but their application in asymmetric catalysis is still underdeveloped in regard to both substrate scope and reaction pathways compared with phosphorus and sulfur ylides. Here a previously unreported asymmetric [4 + 1] annulation reaction of 3-bromooxindoles and electron-deficient 1-azadienes has been developed through ammonium ylide catalysis of a newly designed 2â€Č-methyl α-isocupreine (α-MeIC), efficiently delivering spirocyclic oxindole compounds incorporating a dihydropyrrole motif in excellent enantioselectivity (up to 99% ee). To the best of our knowledge, this work represents the first example of asymmetric catalysis of ammonium ylides bearing α-substitutions, and the catalytic [4 + 1] annulation pathway of ammonium ylides is also unprecedented. Moreover, <sup>1</sup>H NMR, mass spectroscopy, and computational calculation studies were conducted, and the catalytic cycle and a tentative explanation of the enantioselective mechanism have been successfully elucidated

    Enantioselective Alkynylation of Aldehydes by Mixed Aggregates of 3‑Aminopyrrolidine Lithium Amides and Lithium Acetylides

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    Lithium acetylides form, with 3-aminopyrrolidine lithium amides, noncovalent 1/1 mixed aggregates that have been characterized by 1D and 2D multinuclear NMR spectroscopy and DFT computations. The results show that the complex adopts a structure organized around a N–Li–C–Li core and that the acetylide appendage lies within the plane of this quadrilateral, midway between the two lithium cations. These complexes have been employed for the enantioselective alkynylation of a series of aromatic aldehydes and provided the expected propargylic alcohols in ee values up to 85% in THF at −78 °C

    Enantioselective [4 + 1] Annulation Reactions of α‑Substituted Ammonium Ylides To Construct Spirocyclic Oxindoles

    No full text
    Ammonium ylides have a long history in organic synthesis, but their application in asymmetric catalysis is still underdeveloped in regard to both substrate scope and reaction pathways compared with phosphorus and sulfur ylides. Here a previously unreported asymmetric [4 + 1] annulation reaction of 3-bromooxindoles and electron-deficient 1-azadienes has been developed through ammonium ylide catalysis of a newly designed 2â€Č-methyl α-isocupreine (α-MeIC), efficiently delivering spirocyclic oxindole compounds incorporating a dihydropyrrole motif in excellent enantioselectivity (up to 99% ee). To the best of our knowledge, this work represents the first example of asymmetric catalysis of ammonium ylides bearing α-substitutions, and the catalytic [4 + 1] annulation pathway of ammonium ylides is also unprecedented. Moreover, <sup>1</sup>H NMR, mass spectroscopy, and computational calculation studies were conducted, and the catalytic cycle and a tentative explanation of the enantioselective mechanism have been successfully elucidated

    Multiple-Locus Variable-Number Tandem-Repeat Analysis of <i>Mycoplasma pneumoniae</i> Clinical Specimens and Proposal for Amendment of MLVA Nomenclature

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    <div><p><i>Mycoplasma pneumoniae</i> is one of the major respiratory bacterial pathogens that cause pneumonia in humans. Multiple-locus variable-number tandem-repeat analysis (MLVA) is currently the most discriminative method for typing <i>M. pneumoniae</i> strains. To better understand the epidemic of <i>M. pneumoniae</i>-related pneumonia in pediatric patients in Beijing, China, we performed MLVA analysis on 118 specimens collected during an epidemic from 2010–2012. Eleven distinct MLVA types were identified, including four novel types. There was no obvious association of macrolide resistance with any of the genotypes. Considering the instability of VNTR locus Mpn1, we propose an amended MLVA nomenclature system based on the remaining four VNTR loci.</p></div
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