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1.
Org Biomol Chem ; 22(10): 2003-2006, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38376800

RESUMEN

An efficient oxidative thiolation of α-amino carbonyl compounds with thiols by the catalysis of an Earth-abundant nickel salt is disclosed for the first time. A variety of alkyl thiols and (hetero)aryl thiols underwent the reaction well with α-amino ketones and an α-amino ester to produce the desired α,α-aminothiocarbonyl compounds in good to excellent yields under ligand- and base-free conditions.

2.
Adv Mater ; 35(44): e2305495, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37603794

RESUMEN

Fluorescence thermometry has been propelled to the forefront of scientific attention due to its high spatial resolution and remote non-invasive detection. However, recent generations of thermometers still suffer from limited thermal sensitivity (Sr ) below 10% change per Kelvin. Herein, this work presents an ideal temperature-responsive fluorescence material through Te4+ -doped 0D Cs2 ScCl5 ·H2 O, in which isolated polyhedrons endow highly localized electronic structures, and the strong electron-phonon coupling facilitates the formation of self-trapped excitons (STEs). With rising temperature, the dramatic asymmetric expansion of the soft lattice induces increased defects, strong exciton-phonon coupling, and low thermal activation energy, which evokes a rapid de-trapping process of STEs, enabling several orders of magnitude changes in the fluorescence lifetime over a narrow temperature range. After regulating the de-trapping process with different Te4+ doping, a record-high Sr (27.36% K-1 ) of fluorescence lifetime-based detection is achieved at 325 K. The robust stability against multiple heating/cooling cycles and long-term measurements enables a low temperature uncertainty of 0.067 K. Further, the developed thermometers are demonstrated for the remote local monitoring of operating temperature on internal electronic components. It is believed that this work constitutes a solid step towards building the next generation of ultrasensitive thermometers based on low-dimensional metal halides.

3.
Nutrition ; 106: 111864, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36473416

RESUMEN

OBJECTIVES: Anemia is one of the most important nutritional deficiency diseases among schoolchildren worldwide. More attention needs to be focused on anemia prevalence in ethnic minorities in the multiethnic country of China. This study was conducted in Mengzi City, Yunnan Province, which has the largest variety of ethnic minorities in China, to investigate the anemia prevalence among ethnic minority schoolchildren ages 6 to 15 y. METHODS: The plasma hemoglobin concentration of all participants was examined once a year from 2014 to 2020. Anemia was defined as a blood hemoglobin level below 11g/dL, 12g/dL, 13g/dL and 12g/dL for schoolchildren ages 5 to 11y, 12 to 14 y, ages 15 to 19 y males and females, respectively. RESULTS: The overall anemia prevalence (7.3%) was higher than the national level (6.1%). The prevalence among ethnic minorities (8.2%) was higher than among Han Chinese (6.8%), and the prevalence was higher among 6-year-olds (12.2%), females (8.0%), those of Hani Nationality (8.7%), and underweight students (8.5%). The overall prevalence trend of ethnic minorities rose continuously from 2014 to 2020. Ethnic minorities had a higher risk of anemia than did Han Chinese. Overweight schoolchildren (odds ratio [OR], 0.816) and those with obesity (OR, 0.710) had a lower risk of anemia than did students with normal-weight status. CONCLUSIONS: Although the prevalence of anemia among schoolchildren in Mengzi is a mild public health problem, the rate among ethnic minorities is consistently higher than among Han Chinese and keeps rising. Measures to prevent and control anemia need to be prioritized in ethnic minorities, particularly those of Hani Nationality, females, and underweight schoolchildren.


Asunto(s)
Anemia , Etnicidad , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Adulto Joven , Anemia/epidemiología , China/epidemiología , Minorías Étnicas y Raciales , Hemoglobinas , Grupos Minoritarios , Prevalencia , Delgadez
4.
Front Bioeng Biotechnol ; 11: 1335251, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38264579

RESUMEN

Markerless pose estimation based on computer vision provides a simpler and cheaper alternative to human motion capture, with great potential for clinical diagnosis and remote rehabilitation assessment. Currently, the markerless 3D pose estimation is mainly based on multi-view technology, while the more promising single-view technology has defects such as low accuracy and reliability, which seriously limits clinical application. This study proposes a high-resolution graph convolutional multilayer perception (HGcnMLP) human 3D pose estimation framework for smartphone monocular videos and estimates 15 healthy adults and 12 patients with musculoskeletal disorders (sarcopenia and osteoarthritis) gait spatiotemporal, knee angle, and center-of-mass (COM) velocity parameters, etc., and compared with the VICON gold standard system. The results show that most of the calculated parameters have excellent reliability (VICON, ICC (2, k): 0.853-0.982; Phone, ICC (2, k): 0.839-0.975) and validity (Pearson r: 0.808-0.978, p<0.05). In addition, the proposed system can better evaluate human gait balance ability, and the K-means++ clustering algorithm can successfully distinguish patients into different recovery level groups. This study verifies the potential of a single smartphone video for 3D human pose estimation for rehabilitation auxiliary diagnosis and balance level recognition, and is an effective attempt at the clinical application of emerging computer vision technology. In the future, it is hoped that the corresponding smartphone program will be developed to provide a low-cost, effective, and simple new tool for remote monitoring and rehabilitation assessment of patients.

5.
RSC Adv ; 12(37): 24232-24236, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-36128530

RESUMEN

A Cu(i)-catalyzed cross-coupling of primary amines with 2,2'-dibromo-1,1'-biphenyl for the synthesis of polysubstituted carbazole has been achieved. This protocol provides an efficient strategy for the synthesis of carbazole using cheap copper catalysts with diamine ligand, and it provides convenient access to a series of carbazole derivatives in moderate yields.

6.
Front Plant Sci ; 13: 895944, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720529

RESUMEN

An accurate and robust pest detection and recognition scheme is an important step to enable the high quality and yield of agricultural products according to integrated pest management (IPM). Due to pose-variant, serious overlap, dense distribution, and interclass similarity of agricultural pests, the precise detection of multi-classes pest faces great challenges. In this study, an end-to-end pest detection algorithm has been proposed on the basis of deep convolutional neural networks. The detection method adopts a deformable residual network to extract pest features and a global context-aware module for obtaining region-of-interests of agricultural pests. The detection results of the proposed method are compared with the detection results of other state-of-the-art methods, for example, RetinaNet, YOLO, SSD, FPN, and Cascade RCNN modules. The experimental results show that our method can achieve an average accuracy of 77.8% on 21 categories of agricultural pests. The proposed detection algorithm can achieve 20.9 frames per second, which can satisfy real-time pest detection.

7.
Front Neurorobot ; 16: 836184, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35401138

RESUMEN

Knee osteoarthritis is a degenerative disease, which greatly affects the daily life of patients. Total knee replacement (TKR) is the most common method to treat knee joint disorders and relieve knee pain. Postoperative rehabilitation exercise is the key to restore knee joint function. However, there is a lack of a portable equipment for monitoring knee joint activity and a systematic assessment scheme. We have developed a portable rehabilitation monitoring and evaluation system based on the wearable inertial unit to estimate the knee range of motion (ROM). Ten TKR patients and ten healthy adults are recruited for the experiment, then the system performance is verified by professional rehabilitation equipment Baltimore Therapeutic Equipment (BTE) Primus RS. The average absolute difference between the knee ROM and BTE Primus RS of healthy subjects and patients ranges from 0.16° to 4.94°. In addition, the knee ROM of flexion-extension and gait activity between healthy subjects and patients showed significant differences. The proposed system is reliable and effective in monitoring and evaluating the rehabilitation progress of patients. The system proposed in this work is expected to be used for long-term effective supervision of patients in clinical and dwelling environments.

8.
J Phys Condens Matter ; 34(20)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35213852

RESUMEN

The growing demand for optical anti-counterfeiting technology requires the development of new environmentally-friendly smart materials with single-component, multimodal fluorescence. Herein, Cs2ZnBr4:0.3Mn2+&0.15Cu+, as an efficient multimodal luminescent material with excitation-wavelength-dependent emission is reported. Under 365 nm and 254 nm UV light excitation, Cs2ZnBr4:Mn2+&Cu+emits mutually independent green light at 525 nm and blue light at 470 nm, which origin from the emission of Mn2+and the Cu+enhanced self-trapped excitons of Cs2ZnBr4, respectively. Furthermore, the multiexcitonic emission is applied to anti-counterfeiting applications and information encryption and decryption engineering. This codoped strategy provides a colorful step to expand the new metal halide materials in fluorescent anti-counterfeiting and information encryption and decryption.

9.
J Org Chem ; 86(14): 9563-9586, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-34181426

RESUMEN

Oxidation reactions have been extensively studied in the context of the transformations of biomass-derived furans. However, in contrast to the vast literature on utilizing the stoichiometric oxidants, such as m-CPBA and NBS, catalytic methods for the oxidative furan-recyclizations remain scarcely investigated. Given this, we report a means of manganese-catalyzed oxidations of furan with low loading, achieving the Achmatowicz rearrangement in the presence of hydrogen peroxide as an environmentally benign oxidant under mild conditions with wide functional group compatibility.


Asunto(s)
Peróxido de Hidrógeno , Oxidantes , Catálisis , Manganeso , Oxidación-Reducción
10.
PLoS One ; 14(9): e0217555, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31545806

RESUMEN

This study aims to evaluate the quality of clinical practice guidelines(CPGs) for patients with diabetic foot worldwide. A search of guidelines websites, databases and academic institutions websites was performed from January 1st, 2010, until June 30th, 2018. Four assessors independently rated the quality of each CPG using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. Twelve CPGs satisfied the inclusion criteria. The median scores for the 6 AGREE II domains (scope and purpose, stakeholder involvement, rigor of development, clarity of presentation, applicability, and editorial independence) were 92.5%, 72.5%, 71.5%, 89%, 47%, and 77%, respectively. The overall quality of the CPGs was good since the majority of the CPGs reached an overall guideline quality between 5 and 7 points. Different CPGs had widely varying scores in the same area, ranging from 25 to 94 points.


Asunto(s)
Pie Diabético/diagnóstico , Pie Diabético/terapia , Úlcera del Pie/diagnóstico , Úlcera del Pie/terapia , Humanos , Guías de Práctica Clínica como Asunto , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
11.
Artículo en Inglés | MEDLINE | ID: mdl-29713468

RESUMEN

BACKGROUND: Resveratrol, a plant phenol, affords protection against inflammation and oxidative stress. The objective of this study was to investigate the effects of dietary resveratrol supplementation during pregnancy and lactation on the antioxidant status of sows and piglets and on antioxidant gene expression and pathway in placenta. METHODS: Forty sows were allotted to 2 dietary treatments 20 d after breeding. Sows were fed a control diet and a control diet with 300 mg/kg resveratrol. Oxidative stress biomarkers and antioxidant enzymes were measured in the placenta, milk, and plasma of sows and piglets. Antioxidant gene expression and protein expression of Kelch-like ECH-associated protein 1-Nuclear factor E2-related factor 2 (Keap1-Nrf2), nuclear factor kappa B-p65 (NFκB-p65) and sirtuin1 (Sirt1) were quantified in the placenta. RESULTS: Dietary resveratrol increased the litter and piglets weaning weights. Antioxidant status in the milk, placenta and plasma of sows and piglets was partially improved by dietary resveratrol. In placenta, Nrf2 protein expression was increased and Keap1 protein expression was decreased by dietary resveratrol. The mRNA expression of antioxidant genes including catalase (CAT), glutathione peroxidase 1 (GPX1), GPX4, superoxide dismutase 1 (SOD1) and heme oxygenase 1 (HO1), and phase 2 detoxification genes, including glutamate-cysteine ligase modifier (GCLM), microsomal glutathione S-transferase 1(MGST1) and UDP glucuronosyltransferase family 1 member A1 (UGT1A1), was increased by dietary resveratrol. Dietary resveratrol also increased Sirt1 and phosphorylated NFκB-p65 protein expression in the placenta. We failed to observe any influences of dietary resveratrol on pro-inflammatory cytokine levels, including those of interleukin 1ß (IL-1ß), IL-6, IL-8 and tumor necrosis factor α (TNF-α). However, we observed that the mRNA expression of IL-8 in placenta was reduced by maternal resveratrol. In addition, dietary resveratrol showed interactive effects with day of lactation on activities of SOD and CAT and levels of malonaldehyde (MDA) and hydrogen peroxide (H2O2) in milk. CONCLUSIONS: Dietary resveratrol supplementation during pregnancy and lactation improves the antioxidant status of sows and piglets, which is beneficial to the reproductive performance of sows. Dietary resveratrol regulates placental antioxidant gene expression by the Keap1-Nrf2 pathway and Sirt1 in placenta.

12.
Chirality ; 27(10): 761-5, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26317172

RESUMEN

Four novel chiral amino alcohols were synthesized from D-(+)-camphor and utilized as ligands in a Cu(I)-catalyzed asymmetric Henry reaction. The reactions were carried out under mild conditions with excellent enantioselectivities and moderate yields without the exclusion of air or moisture. The highest enantioselectivity was observed up to 94% enantiomeric excess (ee) with ligand in toluene at room temperature.

13.
J Org Chem ; 72(22): 8600-3, 2007 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-17918899

RESUMEN

A facile and efficient synthesis of 1,3-diaryl-5-spirohexahydropyrimidines via a one-pot condensation of anilines, formaldehyde, and cyclohexanones is reported. In this one-pot, three-component reaction, six molecules of reactants are involved and six new covalent bonds are generated. Bicyclic products are obtained from the starting materials in one pot using readily available starting materials and catalysts.


Asunto(s)
Ciclohexanonas/química , Formaldehído/química , Piridinas/química , Pirimidinas/síntesis química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Pirimidinas/química , Estereoisomerismo
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