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1.
Small Methods ; 8(1): e2300650, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37800983

ABSTRACT

In this work, a novel real-time current-voltage (J-V) absorbance spectroscopy (RTJAS) setup is introduced for directly observing halide segregation in mixed halide perovskite solar cells under broadband light illumination, simulating solar exposure. The setup incorporates a broadband light source calibrated to one sun irradiation and a CMOS camera for simultaneous capture of all diffracted wavelengths. J-V measurements are performed concurrently with absorbance spectra collection, enabling in situ analysis of light-induced degradation due to halide segregation, including bandgap shifts and cell performance data. Comparison of photoluminescence measurements with RTJAS data reveals differing rates of bandgap decrease, underscoring the advantages of real-time measurement techniques. The work highlights the importance of accounting for experimental conditions, such as humidity and voltage injection, which can accelerate halide segregation, ultimately emphasizing the need for careful consideration of experimental conditions to accurately characterize perovskite solar cell behavior under realistic conditions.

2.
Nat Commun ; 13(1): 1776, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35365667

ABSTRACT

A catalytic method for the enantioselective and C4-selective functionalization of pyridine derivatives is yet to be developed. Herein, we report an efficient method for the asymmetric ß-pyridylations of enals that involve N-heterocyclic carbene (NHC) catalysis with excellent control over enantioselectivity and pyridyl C4-selectivity. The key strategy for precise stereocontrol involves enhancing interactions between the chiral NHC-bound homoenolate and pyridinium salt in the presence of hexafluorobenzene, which effectively differentiates the two faces of the homoenolate radical. Room temperature is sufficient for this transformation, and reaction efficiency is further accelerated by photo-mediation. This methodology exhibits broad functional group tolerance and enables facile access to a diverse range of enantioenriched ß-pyridyl carbonyl compounds under mild and metal-free conditions.

3.
Diagnostics (Basel) ; 11(7)2021 Jul 07.
Article in English | MEDLINE | ID: mdl-34359308

ABSTRACT

This study aimed to validate the accuracy and prediction performance of machine learning (ML), deep learning (DL), and logistic regression methods in the treatment of medial meniscus posterior root tears (MMPRT). From July 2003 to May 2018, 640 patients diagnosed with MMPRT were included. First, the affecting factors for the surgery were evaluated using statistical analysis. Second, AI technology was introduced using X-ray and MRI. Finally, the accuracy and prediction performance were compared between ML&DL and logistic regression methods. Affecting factors of the logistic regression method corresponded well with the feature importance of the six top-ranked factors in the ML&DL method. There was no significant difference when comparing the accuracy, F1-score, and error rate between ML&DL and logistic regression methods (accuracy = 0.89 and 0.91, F1 score = 0.89 and 0.90, error rate = 0.11 and 0.09; p = 0.114, 0.422, and 0.119, respectively). The area under the curve (AUC) values showed excellent test quality for both ML&DL and logistic regression methods (AUC = 0.97 and 0.94, respectively) in the evaluation of prediction performance (p = 0.289). The affecting factors of the logistic regression method and the influence of the ML&DL method were not significantly different. The accuracy and performance of the ML&DL method in predicting the fate of MMPRT were comparable to those of the logistic regression method. Therefore, this ML&DL algorithm could potentially predict the outcome of the MMRPT in various fields and situations. Furthermore, our method could be efficiently implemented in current clinical practice.

4.
J Clin Med ; 10(15)2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34362027

ABSTRACT

BACKGROUND: The aims of this study were to evaluate the effects of correcting lower limb alignment by total knee arthroplasty (TKA) on the spinopelvic alignment and to identify patients with difference in the knee joint between clinically measured passive motion and the actual standing posture. METHODS: In this retrospective study, 101 patients who underwent TKA and whose serial whole-body EOS X-ray were available were included. The relationship of the knee and spinopelvic alignment was analyzed by evaluating the parameters of standing anterior-posterior and lateral whole-body EOS X-ray. The differences between postoperative passive motion and weight-bearing posture in the knee joint were assessed in both coronal and sagittal planes. Furthermore, the causes of such differences were analyzed. RESULTS: Significant correlations between Δpelvic obliquity and coronal ΔHip-Knee-Ankle (HKA)Rt-Lt angle between the preoperative and 3-month and 1-year postoperative data (p < 0.001 and p < 0.005, respectively) and improved with coronal lower limb alignment close to neutral resulted in decreased pelvic obliquity (p < 0.001, ß = 0.085 and p = 0.005, ß = 0.065, respectively) were observed. The correlations between Δpelvic tilt (PT) and Δsacral slope (SS) and sagittal ΔHKARt-Lt angle were statistically significant (PT: p < 0.001 and p < 0.045; SS: p = 0.002 and p < 0.001, respectively). The improved sagittal alignment close to neutral resulted in decreased PT and increased SS. The difference between postoperative passive motion and the weight-bearing posture of the knee joint was correlated with lumbar lordosis and sagittal C7 plumb line-sacrum distance (p = 0.042 and p < 0.001, respectively). CONCLUSIONS: The correction of lower limb alignment with TKA affected pelvic parameters dominantly; however, there was little effect on the spinal alignment. Additionally, patients with anterior stooping or lumbar flat back demonstrated difference in extension between passive knee motion and standing. Therefore, rather than only focusing on changes in the knee alignment correction, knee surgeons should also evaluate the spinopelvic alignment before surgery to consider the prognosis of the standing and predict the possible changes in the whole-body alignment. This preoperative assessment may improve the prognosis of TKA.

5.
J Clin Med ; 10(8)2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33921685

ABSTRACT

Weight bearing whole-leg radiograph (WLR) is essential to assess lower limb alignment such as weight bearing line (WBL) ratio. The purpose of this study was to develop a deep learning (DL) model that predicts the WBL ratio using knee standing AP alone. Total of 3997 knee AP & WLRs were used. WBL ratio was used for labeling and analysis of prediction accuracy. The WBL ratio was divided into seven categories (0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6). After training, performance of the DL model was evaluated. Final performance was evaluated using 386 subjects as a test set. Cumulative score (CS) within error range 0.1 was set with showing maximum CS in the validation set (95% CI, 0.924-0.970). In the test set, mean absolute error was 0.054 (95% CI, 0.048-0.061) and CS was 0.951 (95% CI, 0.924-0.970). Developed DL algorithm could predict the WBL ratio on knee standing AP alone with comparable accuracy as the degree primary physician can assess the alignment. It can be the basis for developing an automated lower limb alignment assessment tool that can be used easily and cost-effectively in primary clinics.

6.
Angew Chem Int Ed Engl ; 59(50): 22514-22522, 2020 12 07.
Article in English | MEDLINE | ID: mdl-32864829

ABSTRACT

Bioconjugation methods using visible-light photocatalysis have emerged as powerful synthetic tools for the selective modification of biomolecules under mild reaction conditions. However, the number of photochemical transformations that allow successful protein bioconjugation is still limited because of the need for stringent reaction conditions. Herein, we report that a newly developed water-compatible fluorescent photosensitizer QPEG can be used for visible-light-induced cysteine-specific bioconjugation for the installation of QPEG by exploiting its intrinsic photosensitizing ability to activate the S-H bond of cysteine. The slightly modified QCAT enables the effective photocatalytic cysteine-specific conjugation of biologically relevant groups. The superior reactivity and cysteine selectivity of this methodology was further corroborated by traceless bioconjugation with a series of complex peptides and proteins under biocompatible conditions.


Subject(s)
Alkenes/chemistry , Biocompatible Materials/chemistry , Cysteine/chemistry , Light , Photosensitizing Agents/chemistry , Sulfhydryl Compounds/chemistry , Click Chemistry , Molecular Structure , Photochemical Processes
7.
Org Lett ; 21(9): 3417-3421, 2019 05 03.
Article in English | MEDLINE | ID: mdl-31008610

ABSTRACT

Reported herein is the photochemical activity of quinolinone-containing substrates that directly reach an excited state upon light absorption to trigger radical-based bond-forming processes. The presented transformations allow divergent construction of valuable dihydro- or tetrahydrophenanthridin-6(5 H)-ones through the generation of S- or P-centered radicals, subsequent radical addition, cyclization, and a hydrogen atom transfer/electron transfer sequence. This strategy demonstrates the potential generality of quinolinone-tethered substrates to directly participate in the photoexcitation for the development of useful synthetic methods.

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