CBr4 as a Mild Oxidant-Enabled Oxidation of a sp3 C-H Bond: A Facile Synthesis of the Persistent Iminium Salts of Tetrahydroisoquinolines.

Using CBr4 as a mild oxidant, the direct C-H bond oxidation of N-aryltetrahydroisoquinolines was achieved, giving a series of the corresponding iminium salts in high yields under metal- and photo-free reaction conditions. This reaction is superior in high yields and good functional group tolerance, and the late-stage derivatization showed that these iminium salts can readily be applied to the synthesis of the functionalized THIQs.

Quantitative Fluorescent Lateral Flow Strip Sensor for Myocardial Infarction Using Purity-Color Upconversion Nanoparticles.

Acute myocardial infarction is a serious cardiovascular disease and poses significant risks to human health. Its early diagnosis and real-time detection are of great importance. Herein, we design a low-cost device that has a high sensitivity of cTnT and cTnI detection. Dual-color upconversion nanoparticles (UCNPs) are prepared as probes, which not only have high-purity red upconversion luminescence (UCL) under 980 or 808 nm excitation but also achieve good temperature sensing. Temperature-dependent multicolor emission excitation is obtained, and the color turns from white to orange and red with increasing temperature. In particular, the maximum SR and SA values based on nonthermally coupled levels are 4.76% K-1 and 8.6% K-1, which are higher than those based on thermally coupled levels. With the UCNPs-based lateral flow strip (LFS), the specific detection of cTnI and cTnT antigens in samples is achieved with a detection limit of 0.001 ng/mL, which is 1 order of magnitude lower than that of their clinical cutoff. The UCNPs-LFS device has a low-cost laser diode and a simplified laser and permits a mobile-phone camera to collect the results, which has an important influence on the field of biomarker sensing.

[Clinical Efficacy of Anchor Suture Bridge Technique for Avulsion Fractures of the Posterior Cruciate Ligament Tibial Insertion Point in the Knee Joint]. / é”šé’‰ç¼çº¿æ¡¥æŠ€æœ¯å¯¹è†å ³èŠ‚åŽäº¤å‰éŸ§å¸¦èƒ«éª¨æ­¢ç‚¹æ’•è„±éª¨æŠ˜çš„ä¸´åºŠç–—æ•ˆ.

Objective: To investigate the clinical efficacy of the anchor suture bridge technique in treating avulsion fractures at the tibial insertion point of the posterior cruciate ligament (PCL) in the knee joint. Methods: In this study, we reviewed 80 patients with PCL tibial avulsion fractures treated using the anchor suture bridge technique in our department from February 2010 to December 2023. Follow-ups were conducted starting at 3 months post-surgery, then every 3 months until 12 months post-surgery. Clinical and follow-up data of each patient were analyzed. The Lysholm and Hospital for Special Surgery Knee-Rating Scale (HSS) scores of knee function before surgery and at the last follow-up were compared to assess the surgical treatment outcome. Results: The 80 patients were followed up for an average of (12.16±1.08) months post-surgery. Re-examination X-rays showed that all fractures had healed, with an average healing time of (3.66±0.51) months. All patients recovered well, with primary healing of surgical incisions and no complications such as neurovascular injury, skin necrosis, incision infection, fracture displacement, or ligament laxity. Postoperative knee Lysholm and HSS scores were significantly higher than preoperative scores. At the last follow-up, the Lysholm score increased from (46.30±6.10) preoperatively to (90.85±3.27), and the HSS score increased from (45.30±5.80) to (91.15±2.66), with statistically significant differences (P<0.025). Conclusion: The anchor suture bridge technique is effective in treating avulsion fractures of the PCL tibial insertion point in the knee joint. It has a high safety profile and leads to good postoperative knee function recovery, with no serious postoperative complications, demonstrating excellent clinical efficacy.

C-H Bond Activation Relay (CHAR) of Proline Ester Derivatives Promoted by In Situ Triarylamine Radical Cation: Selective Synthesis of 4-Bromopyrrole Derivatives.

Using the in situ generated triarylamine radical cation as an initiator, the sp3 C-H bond of proline esters was smoothly oxidized and brominated through C-H activation relay (CHAR), giving a series of 4-bromopyrroles in good yields with high regioselectivity. The mechanistic study revealed that the oxidation of the active C-H bond initiated the followed 1,5-HAT and bromination, which provides a new method to realize the functionalization of the remote C-H bond.

A comprehensive segmentation of chest X-ray improves deep learning-based WHO radiologically confirmed pneumonia diagnosis in children.

OBJECTIVES: To investigate a comprehensive segmentation of chest X-ray (CXR) in promoting deep learning-based World Health Organization's (WHO) radiologically confirmed pneumonia diagnosis in children. METHODS: A total of 4400 participants between January 2016 and June 2021were identified for a cross-sectional study and divided into primary endpoint pneumonia (PEP), other infiltrates, and normal groups according to WHO's diagnostic criteria. The CXR was divided into six segments of left lung, right lung, mediastinum, diaphragm, ext-left lung, and ext-right lung by adopting the RA-UNet. To demonstrate the benefits of lung field segmentation in pneumonia diagnosis, the segmented images and images that were not segmented, which constituted seven segmentation combinations, were fed into the CBAM-ResNet under a three-category classification comparison. The interpretability of the CBAM-ResNet for pneumonia diagnosis was also performed by adopting a Grad-CAM module. RESULTS: The RA-UNet achieved a high spatial overlap between manual and automatic segmentation (averaged DSC = 0.9639). The CBAM-ResNet when fed with the six segments achieved superior three-category diagnosis performance (accuracy = 0.8243) over other segmentation combinations and deep learning models under comparison, which was increased by around 6% in accuracy, precision, specificity, sensitivity, F1-score, and around 3% in AUC. The Grad-CAM could capture the pneumonia lesions more accurately, generating a more interpretable visualization and enhancing the superiority and reliability of our study in assisting pediatric pneumonia diagnosis. CONCLUSIONS: The comprehensive segmentation of CXR could improve deep learning-based pneumonia diagnosis in childhood with a more reasonable WHO's radiological standardized pneumonia classification instead of conventional dichotomous bacterial pneumonia and viral pneumonia. CLINICAL RELEVANCE STATEMENT: The comprehensive segmentation of chest X-ray improves deep learning-based WHO confirmed pneumonia diagnosis in children, laying a strong foundation for the potential inclusion of computer-aided pediatric CXR readings in precise classification of pneumonia and PCV vaccine trials efficacy in children. KEY POINTS: • The chest X-ray was comprehensively segmented into six anatomical structures of left lung, right lung, mediastinum, diaphragm, ext-left lung, and ext-right lung. • The comprehensive segmentation improved the three-category classification of primary endpoint pneumonia, other infiltrates, and normal with an increase by around 6% in accuracy, precision, specificity, sensitivity, F1-score, and around 3% in AUC. • The comprehensive segmentation gave rise to a more accurate and interpretable visualization results in capturing the pneumonia lesions.

Halogen Bond (XB) Promoted α-Tribromomethylation of N-Aryltetrahydroisoquinolines and Further Cyclization to 5,6-Dihydroindolo[2,1-a]isoquinolines.

Using CBr4 as a halogen bond donor and the source of tribromomethyl group, a halogen bond promoted tribromomethylation of N-aryltetrahydroisoquinolines was achieved. This reaction was also extended to the construction of the dibenzopyrrocoline alkaloid skeleton through a one-pot process. The mechanistic study confirmed the existence of the halogen bond.

Numerical and experimental performance evaluation of a laser-concentrated photovoltaic-thermoelectric generator hybrid system.

Thermal management of concentrated photovoltaic (CPV) modules is essential to avoid the decrease in conversion efficiency caused by temperature rise during their operation. This is even more important for laser-concentrated CPV hybrid systems where out-of-control temperature rise is more likely to happen. In this research, a three-dimensional simulation model for a concentrated photovoltaic-thermoelectric (CPV-TE) hybrid system was studied to optimize its parameters and improve its conversion efficiency under laser radiation. Based on the simulation results, an integrated CPV-TE device was designed, fabricated, and tested under a high-power laser. The novel integrated CPV-TE system utilizes growing electrodes to encapsulate CPV directly on the TEG. Compared to conventional CPV-TE systems that utilize silicone-filled, the integrated CPV-TE system reduces contact thermal resistance and increases output power as well as conversion efficiency. To the best of our knowledge, this is the first study to discuss and optimize a CPV-TE hybrid system for laser radiation. In addition, this research improves the efficiency of laser energy conversion, increases the reliability and stability of the system, and may facilitate the promotion of optical wireless and fiber power transmission systems in future applications.

Tris(4-bromophenyl)aminium Hexachloroantimonate as a "Waste-Utilized"-Type Initiator-Promoted C-H Chlorination via C-H Activation Relay: Synthesis of Chlorinated Pyrroles.

Using tris(4-bromophenyl)aminium hexachloroantimonate as a "waste-utilized"-type initiator, the aerobic oxidation of the sp3 C-H bond of proline esters was realized via C-H activation relay, giving a series of halogenated pyrroles in high yields. The mechanistic study revealed that the counterion, SbCl6-, was involved in the radical chlorination process, which provides a new way to understand the role of the counterions.

Protein intake and risk of inflammatory bowel disease: A meta-analysis.

BACKGROUND AND OBJECTIVES: Although the association between dietary protein intake and inflammatory bowel disease (IBD) risk has been investigated, the results are inconsistent. Therefore, we conducted a meta-analysis to reassess the relationship between dietary protein intake and IBD risk. METHODS AND STUDY DESIGN: The PubMed, Web of Knowledge, and Wanfang databases were searched for pertinent studies through January 31, 2020. Relative risks (RRs) with 95% confidence intervals (CIs) were derived using a random-effect model. Subgroup analyses according to disease type, geographic location, and sex; sensitivity analysis; and publication bias analysis were performed. RESULTS: The current report includes 8 articles consisting of 12 studies with 1069 cases and 330,676 participants. The pooled RR (95% CI) of the highest vs. the lowest categories of dietary protein intake for the IBD risk was 1.561 (0.384-6.347) in cohort studies and 1.060 (0.663-1.694) in case-control studies. Evidence of heterogeneity was found both in cohort studies (I2=86.4%, p=0.007) and in case-control studies (I2=49.0%, p=0.039). However, the association was significant among Asian populations (RR=1.675, 95% CI=1.096-2.559) but not in other populations. We did not find any relationship of dietary protein intake with the risk of either Crohn's disease or ulcerative colitis. CONCLUSIONS: Based on limited information, the highest dietary protein intakes among Asians may increase the risk of IBD, undifferentiated for ulcerative colitis or Crohn's disease. This may reflect dietary patterns for which protein is a marker rather than implicate protein itself.

Two-Dimensional All-in-One Sulfide Monolayers Driving Photocatalytic Overall Water Splitting.

For realizing scalable solar hydrogen synthesis, the development of visible-light-absorbing photocatalysts capable of overall water splitting is essential. Metal sulfides can capture visible light efficiently; however, their utilization in water splitting has long been plagued by the poor resilience against hole oxidation. Herein, we report that the ZnIn2S4 monolayers with dual defects (Ag dopants and nanoholes) accessed via cation exchange display stoichiometric H2 and O2 evolution in pure water under visible light irradiation. In-depth characterization and modeling disclose that the dual-defect structure endows the ZnIn2S4 monolayers with optimized light absorption and carrier dynamics. More significantly, the dual defects cooperatively function as active sites for water oxidation (Ag dopants) and reduction (nanoholes), thus leading to steady performance in photocatalytic overall water splitting without the assistance of cocatalysts. This work demonstrates a feasible way for fulfilling "all-in-one" photocatalyst design and manifests its great potential in addressing the stability issues associated with sulfide-based photocatalysts.

First-Principles Calculation of Photoelectric Property in Upconversion Materials through In3+ Doping.

Multicolor turning holds great promise in optical intelligent recognition and optical imaging. Here, Er3+, Yb3+, and In codoped ZnO (Er/Yb/IZO) with a uniform block strucuture is obtained. The doping of In3+ ions enhances the multicolor upconversion luminescence (UCL) intensity of Er/Yb/IZO. Particularlly, the UCL of Er/Yb/I2ZO turns from red through yellow to dominant green emission via increasing density power from 2.54 to 10.19 W/cm2, thus realizing the power sensitiviy. First-principles theory is used to design a In3+, Yb3+, and Er3+ codoped ZnO. The band structure, total density of state and optical coefficient of Er/Yb/IZO have been studied via a generalized gradient approximation within density functional theory (DFT). The potential electron density and total electron density of the O atom increase with In3+ and Er3+/Yb3+ doping, which indicate that substitution of Zn2+ by In3+ and Er3+/Yb3+ generate positive vacancies on the surface. The band gap of Er/Yb/IZO decreases compare with that of pure ZnO. Furthermore, the optical coefficient of In3+ doping is enhanced compare with that of pure ZnO via using DFT calculations.

Segmenting nailfold capillaries using an improved U-net network.

To assess the microcirculation in a patient's capillaries, clinicians often use the valuable and non-invasive diagnostic tool of nailfold capillaroscopy (NC). In particular, evaluating the images that result from NC is particularly important for diagnosing diseases in which the capillary morphology is altered. However, NC images are generally of poor quality, such that analyzing them is difficult and time consuming. Thus, the purpose of this work was to determine a way to segment the capillaries in poor-quality NC images accurately. To do this, we proposed using a deep neural network with a Res-Unet structure. The network combines the residual network (ResNet) and the U-Net to establish an encoding-decoding network and to deepen the layers in the network to preserve the features of the deep layer. The network was trained on 30 nailfold capillary images to discriminate the pixels belonging to capillaries, and it was then tested on a dataset consisting of 20 images to achieve a binarized map. The mean accuracy was 91.72% and the mean Dice score was 97.66% compared to the ground truth, which indicates that using Res-Unet to perform capillary segmentation in NC images had good performance.

Silica-Coated Ga(III)-Doped ZnO: Yb3+, Tm3+ Upconversion Nanoparticles for High-Resolution in Vivo Bioimaging using Near-Infrared to Near-Infrared Upconversion Emission.

Photon avalanche has attracted much attention due to the unique nonlinear luminescence dynamics and high-efficiency upconversion luminescence properties. In this paper, we present a simple but effective method to prepare Yb/Tm/GZO@SiO2 (GZO = gallium-doped zinc oxide). Low-threshold photon-avalanche luminescence was obtained below the milliwatts (2.5 mW) in Yb/Tm/GZO@SiO2 core/shell nanoparticles. Compared with Yb/Tm/GZO nanoparitlces, near-infrared (NIR) upconversion luminescence intensity of Yb/Tm/GZO@SiO2 was enhanced ∼12 times. Furthermore, Yb/Tm/GZO@SiO2 acted as luminescence probe, which realized the red fluorescence imaging of myocardial tissue. With injection of 6 mg/kg Yb/Tm/GZO@SiO2, the red NIR fluorescence imaging of heart tissue became brighter. The experimental results of histological assessments of representative organs indicated that there was low toxicity of Yb/Tm/GZO@SiO2 in vivo. This study proved that Yb/Tm/GZO@SiO2 posed a promising potential for bioimaging applications.

Influence of Silica Surface Coating on Operated Photodynamic Therapy Property of Yb3+-Tm3+: Ga(III)-Doped ZnO Upconversion Nanoparticles.

Photodynamic therapy (PDT) is a noninvasive therapeutic technique. Upconversion nanoparticles (UCNPs) hold promise for photodynamic therapy (PDT). UCNPs with antistokes emission can improve the tissue penetration depth of PDT. However, the low upconversion efficiency poses a strong limit on further development of PDT. The core/shell structure Yb/Tm/GZO@SiO2 UCNPs are designed, which can form multistep cascade energy transfer from sillica shell to core Ga-doped Yb/Tm/ZnO. Compared with Yb/Tm/ZnO upconversion (UC) semiconductor nanoparticles (SNCs), the multistep cascade energy transfer process provides about seven times enhanced UCL emission. For the UCL-optimized core/shell upconversion SNCs of Yb7/Tm0.5/G3ZO@mSiO2, the Yb3+ energy transfer efficiency is determined to be as high as ∼81% under 980 nm laser excitation. In addition, the Yb7/Tm0.5/G3ZO@mSiO2 core/shell UCNPs have an excellent PDT treatment for Hela cells under 980 nm laser excitation.

Ga3+ Doping Induced Simultaneous Size/Shape Control, Enhanced Red Upconversion Luminescence, and Improved X-ray Imaging of ZnO:Yb/Tm for Multifunctional Nanoprobes.

We report that the efficient Ga3+-doped ZnO:Yb/Tm (7/0.5 mol %) upconversion nanoparticles (UCNPs) can simultaneously control size/shape and enhance red upconversion luminescence (UCL) by transition-metal Ga3+ doping. The dynamic decay time reveals that the intensity of red upconversion luminescence increases with increasing Ga3+ content. Furthermore, upconversion nanoparticles are fabricated through silica layer with Stöber method. The lung of mouse with the ZnO:Ga/Yb/Tm@SiO2 injection can be readily visualized using X-ray imaging, which will influence the field of biological probe based on UCNPs@SiO2.

Effect of silica surface coating on the luminescence lifetime and upconversion temperature sensing properties of semiconductor zinc oxide doped with gallium(III) and sensitized with rare earth ions Yb(III) and Tm(III).

Optical sensing of temperature by measurement of the ratio of the intensities of the 700 nm emission and the 800 nm emission of Ga(III)-doped ZnO (GZO) nanoparticles (NPs) and of GZO NPs coated with a silica shell are demonstrated at 980 nm excitation. It is found that the relative sensitivity of SiO2@Yb/Tm/GZO is 6.2% K-1 at a temperature of 693 K. This is ~3.4 times higher than that of Yb/Tm/GZO NPs. Obviously, the SiO2 shell structure decreases the rate of the nonradiative decay. The decay time of the 800 nm emission of the Yb/Tm/GZO NPs (15 mol% Ga; 7 mol% Yb; 0.5 mol% Tm) displays a biexponential decay with a dominant decay time of 148 µs and a second decay time of ~412 µs. The lifetime of the Yb/Tm/GZO NPs at 293 K, and of the SiO2@Yb/Tm/GZO NPs are ~412 µs. Both the Yb/Tm/GZO and SiO2@Yb/Tm/GZO can be used up to 693 K. These results indicate that the SiO2 shell on the Yb/Tm/GZO is beneficial in terms of sensitivity and resolution. Graphical abstract The enhancement the decay time and thermal sensitivity in the SiO2@Yb/Tm/GZO shell@core structure have been studied compared to the Ga(III)-doped Yb/Tm-doped ZnO (Yb/Tm/GZO). The SiO2@Yb/Tm/GZO have good thermal accuracy up to 693 °C.

[Factors influencing the clinical pregnancy rate following intrauterine insemination].

OBJECTIVE: To investigate the factors that affect the clinical pregnancy rate after intrauterine insemination (IUI). METHODS: We retrospectively analyzed the clinical data of 611 IUI cycles and analyzed the relationship of the clinical pregnancy rate after IUI with the female age, infertility duration, type of infertility, cycle number, cycle protocol, thickness and type of endometrium, and semen parameters before processing. RESULTS: The clinical pregnancy rate was significantly higher in the ovulation induction than in the natural ovulation cycles (23.03% vs 11.03%, P < 0.01), but lower in the 4th cycle and above than in the 1st, 2nd, and 3rd cycles (2.04% vs 21.30%, 18.13%, and 12.67%, P < 0.01). Marked decreases were found in the clinical pregnancy rate in the females aged ≥ 40 years and the cases with pre-processing total progressively motile sperm count (TPMSC) < 10 x 10(6), progressive motile sperm < 20%, or morphologically normal sperm < 2% (all P < 0.05). Logistic regression analysis revealed the cycle protocol, cycle number, and percentage of progressively motile sperm as three predictive variables affecting the clinical pregnancy rate after IUI (P < 0.05). CONCLUSION: The cycle protocol, cycle number, percentage of progressively motile sperm, female age, TPMSC, and sperm morphology are the main factors affecting the clinical pregnancy rate following IUI, while infertility duration, type of infertility, and thickness and type of endometrium exert little influence.

The prevalence of dementia in urban and rural areas of China.

OBJECTIVE: The Chinese population has been aging rapidly and the country's economy has experienced exponential growth during the past three decades. The goal of this study was to estimate the changes in the prevalence of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) among elderly Chinese individuals and to analyze differences between urban and rural areas. METHODS: For the years 2008 to 2009, we performed a population-based cross-sectional survey with a multistage cluster sampling design. Residents aged 65 years and older were drawn from 30 urban (n = 6096) and 45 rural (n = 4180) communities across China. Participants were assessed with a series of clinical examinations and neuropsychological measures. Dementia, AD, and VaD were diagnosed according to established criteria via standard diagnostic procedures. RESULTS: The prevalence of dementia, AD, and VaD among individuals aged 65 years and older were 5.14% (95% CI, 4.71-5.57), 3.21% (95% CI, 2.87-3.55), and 1.50% (95% CI, 1.26-1.74), respectively. The prevalence of dementia was significantly higher in rural areas than in urban ones (6.05% vs. 4.40%, P < .001). The same regional difference was also seen for AD (4.25% vs. 2.44%, P < .001) but not for VaD (1.28% vs. 1.61%, P = .166). The difference in AD was not evident when the sample was stratified by educational level. Moreover, the risk factors for AD and VaD differed for urban and rural populations. CONCLUSIONS: A notably higher prevalence of dementia and AD was found in rural areas than in urban ones, and education might be an important reason for the urban-rural differences.

The prevalence of mild cognitive impairment and its etiological subtypes in elderly Chinese.

BACKGROUND: Epidemiologic studies on mild cognitive impairment (MCI) are limited in China. METHODS: Using a multistage cluster sampling design, a total of 10,276 community residents (6096 urban, 4180 rural) aged 65 years or older were evaluated and diagnosed with normal cognition, MCI, or dementia. MCI was further categorized by imaging into MCI caused by prodromal Alzheimer's disease (MCI-A), MCI resulting from cerebrovascular disease (MCI-CVD), MCI with vascular risk factors (MCI-VRF), and MCI caused by other diseases (MCI-O). RESULTS: The prevalences of overall MCI, MCI-A, MCI-CVD, MCI-VRF, and MCI-O were 20.8% (95% confidence interval [CI] = 20.0-21.6%), 6.1% (95% CI = 5.7-6.6%), 3.8% (95% CI = 3.4-4.2%), 4.9% (95% CI = 4.5-5.4%), and 5.9% (95% CI = 5.5-6.4%) respectively. The rural population had a higher prevalence of overall MCI (23.4% vs 16.8%, P < .001). CONCLUSIONS: The prevalence of MCI in elderly Chinese is higher in rural than in urban areas. Vascular-related MCI (MCI-CVD and MCI-VRF) was most common.

Advanced Biological Applications of Cerium Oxide Nanozymes in Disease Related to Oxidative Damage.

Due to their excellent catalytic activities, cerium oxide nanoparticles have promise as biological nanoenzymes. A redox reaction occurs between Ce3+ ions and Ce4+ ions during which they undergo conversion by acquiring or losing electrons as well as forming oxygen vacancies (or defects) in the lattice structure, which can act as antioxidant enzymes and simulate various enzyme activities. A number of cerium oxide nanoparticles have been engineered with multienzyme activities, including catalase, superoxide oxidase, peroxidase, and oxidase mimetic properties. Cerium oxide nanoparticles have nitric oxide radical clearing and radical scavenging properties and have been widely used in a number of fields of biology, including biomedicine, disease diagnosis, and treatment. This review provides a comprehensive introduction to the catalytic mechanisms and multiple enzyme activities of cerium oxide nanoparticles, along with their potential applications in the treatment of diseases of the brain, bones, nerves, and blood vessels.