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1.
Adv Mater ; 36(25): e2309172, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38391035

ABSTRACT

X-ray circular dichroism, arising from the contrast in X-ray absorption between opposite photon helicities, serves as a spectroscopic tool to measure the magnetization of ferromagnetic materials and identify the handedness of chiral crystals. Antiferromagnets with crystallographic chirality typically lack X-ray magnetic circular dichroism because of time-reversal symmetry, yet exhibit weak X-ray natural circular dichroism. Here, the observation of giant natural circular dichroism in the Ni L3-edge X-ray absorption of Ni3TeO6 is reported, a polar and chiral antiferromagnet with effective time-reversal symmetry. To unravel this intriguing phenomenon, a phenomenological model is proposed that classifies the movement of photons in a chiral crystal within the same symmetry class as that of a magnetic field. The coupling of X-ray polarization with the induced magnetization yields giant X-ray natural circular dichroism, revealing typical ferromagnetic behaviors allowed by the symmetry in an antiferromagnet, i.e., the altermagnetism of Ni3TeO6. The findings provide evidence for the interplay between magnetism and crystal chirality in natural optical activity. Additionally, the first example of a new class of magnetic materials exhibiting circular dichroism is established with time-reversal symmetry.

2.
Phys Rev Lett ; 131(11): 116002, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37774302

ABSTRACT

The extremely overdoped cuprates are generally considered to be Fermi liquid metals without exotic orders, whereas the underdoped cuprates harbor intertwined states. Contrary to this conventional wisdom, using Cu L_{3}-edge and O K-edge resonant x-ray scattering, we reveal a charge order (CO) correlation in overdoped La_{2-x}Sr_{x}CuO_{4} (0.35≤x≤0.6) beyond the superconducting dome. This CO has a periodicity of ∼6 lattice units with correlation lengths of ∼20 lattice units. It shows similar in-plane momentum and polarization dependence and dispersive excitations as the CO of underdoped cuprates, but its maximum intensity differs along the c direction and persists up to 300 K. This CO correlation cannot be explained by the Fermi surface instability and its origin remains to be understood. Our results suggest that CO is prevailing in the overdoped metallic regime and requires a reassessment of the picture of overdoped cuprates as weakly correlated Fermi liquids.

3.
Front Endocrinol (Lausanne) ; 13: 923804, 2022.
Article in English | MEDLINE | ID: mdl-35846324

ABSTRACT

Objectives: Intraoperative neuromonitoring (IONM) is a useful tool to evaluate the function of recurrent laryngeal nerve (RLN) in thyroid surgery. This study aimed to determine the necessity and value of routinely testing the proximal and distal ends of RLN. Methods: In total, 796 patients undergoing monitored thyroidectomies with standardized procedures were enrolled. All 1346 RLNs with visual integrity of anatomical continuity were routinely stimulated at the most proximal (R2p signal) and distal (R2d signal) ends after complete RLN dissection. The EMG amplitudes between R2p and R2d signals were compared. If the amplitude of R2p/R2d ratio reduction (RPDR) was over 10% or loss of signal (LOS) occurred, the exposed RLN was mapped to identify the injured point. Pre- and post-operative vocal cord (VC) mobility was routinely examined with video-laryngofiberscope. Results: Nerve injuries were detected in 108 (8%) RLNs, including 94 nerves with incomplete LOS (RPDR between 13%-93%) and 14 nerves with complete LOS. The nerve injuries were caused by traction in 80 nerves, dissecting trauma in 23 nerves and lateral heat spread of energy-based devices in 5 nerves. Symmetric VC mobility was found in 72 nerves with RPDR ≤50%. The occurrence of abnormal VC mobility (weak or fixed) was 14%, 67%, 100%, and 100% among the different RPDR stratifications of 51%-60%, 61%-70%, 71%-80%, and 81-93%, respectively. Of the 14 nerves with complete LOS, all showed fixed VC mobility. Permanent VC palsy occurred in 2 nerves with thermal injury. Conclusion: Routinely testing the proximal and distal ends of exposed RLN helps detect unrecognized partial nerve injury, elucidate the injury mechanism and determine injury severity. The procedure provides accurate information for evaluating RLN function after nerve dissection and should be included in the standard IONM procedure.


Subject(s)
Recurrent Laryngeal Nerve , Vocal Cord Paralysis , Electromyography/adverse effects , Electromyography/methods , Humans , Monitoring, Intraoperative/methods , Recurrent Laryngeal Nerve/surgery , Thyroidectomy/adverse effects , Thyroidectomy/methods , Vocal Cord Paralysis/etiology , Vocal Cord Paralysis/surgery
4.
J Phys Chem C Nanomater Interfaces ; 126(20): 8752-8759, 2022 May 26.
Article in English | MEDLINE | ID: mdl-35655938

ABSTRACT

We present the cobalt 2p3d resonant inelastic X-ray scattering (RIXS) spectra of Co3O4. Guided by multiplet simulation, the excited states at 0.5 and 1.3 eV can be identified as the 4 T 2 excited state of the tetrahedral Co2+ and the 3 T 2g excited state of the octahedral Co3+, respectively. The ground states of Co2+ and Co3+ sites are determined to be high-spin 4 A 2(T d ) and low-spin 1 A 1g (Oh ), respectively. It indicates that the high-spin Co2+ is the magnetically active site in Co3O4. Additionally, the ligand-to-metal charge transfer analysis shows strong orbital hybridization between the cobalt and oxygen ions at the Co3+ site, while the hybridization is weak at the Co2+ site.

5.
Ear Nose Throat J ; : 1455613221086032, 2022 Mar 29.
Article in English | MEDLINE | ID: mdl-35348022

ABSTRACT

Accidental swallowing of fish bone is one of the most common emergencies in the otolaryngology department. The impacted fish bones are usually found in the palatine tonsil, base of the tongue, valleculae, pyriform sinus, and esophagus, which can be successfully removed after a thorough examination. However, in some cases, the fish bone may penetrate into the neck soft tissue and migrate to extraluminal organs, causing infection, abscess formation, or rupture of vessels. In such cases, prompt recognition and immediate removal of the impacted fish bone are necessary. Herein, we report a rare case of a 60-year-old woman who had accidently swallowed a fish bone 10 days prior to visiting the outpatient department. The fiberoptic scope and head and neck computed tomography scans were obtained from the outpatient department. The fish bone was found to migrate from the upper esophagus to the left thyroid gland. First, a rigid esophageal endoscopy was performed in the operating room, but no obvious fish bone was noted over the esophagus. Finally, the fish bone was removed via exploratory cervicotomy with left-sided total lobectomy of the thyroid. The patient recovered after the operation, and there were no further complications during the 3 years of follow-up.

6.
Inorg Chem ; 61(5): 2595-2602, 2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35061382

ABSTRACT

Organic-inorganic hybrid metal halides have recently attracted attention in the global research field for their bright light emission, tunable photoluminescence wavelength, and convenient synthesis method. This study reports the detailed properties of (C10H16N)2MnBr4, which emits bright green light with a high photoluminescence quantum yield. Results of powder X-ray diffraction, photoluminescence, thermogravimetric analysis, and Raman spectra show the phase transition of (C10H16N)2MnBr4 at 430 K. This phase transition was identified as the solid to liquid state of (C10H16N)2MnBr4. Moreover, the pressure- and temperature-induced relationship between structural and optical properties in (C10H16N)2MnBr4 can be identified. This investigation provides deep insights into the luminescent properties of metal halide crystals and promotes further research.

7.
Hu Li Za Zhi ; 66(4): 71-78, 2019 Aug.
Article in Chinese | MEDLINE | ID: mdl-31342503

ABSTRACT

BACKGROUND & PROBLEMS: An investigation found that 66.7% of the neonatal hypothermia (body temperature < 36.5°C) cases diagnosed within one hour of transfer from the delivery room in our hospital were affected by a significantly increased risk of physiological abnormalities, which subsequently increased their risk for mortality. Therefore, monitoring and maintaining the normal body temperature of newborn infants are vital in infant care. PURPOSE: This project aimed to improve the current situation of neonatal hypothermia. RESOLUTION: This project was implemented from Oct. 1, 2016 to Oct. 31, 2017 and used several approaches to improve neonatal hypothermia. A neonatal hypothermia caring protocol was developed and the infant admission materials were standardized; the infant hypothermia alert card and posters were displayed in easy-to-notice locations; an in-service training course on neonatal hypothermia was provided; and an infant hypothermia care checklist was tabulated for examination and recognition. RESULTS: After the implementation of this project, the average time required to raise the body temperature of infants to normal (36.5°C) was 1.5 hours, which was 2 hours faster than the pre-project time of 3.5 hours. Moreover, the time needed to raise the body temperature to normal was one hour for newborn infants with birthweights ≥ 2,500 grams, which was one hour faster than the pre-project time of two hours, and 1.5 hours for newborn infants with birthweights < 2,500 grams, which was three hours faster than the pre-project time of 4.5 hours. The goals of this project were effectively achieved in both groups. CONCLUSIONS: Neonatal hypothermia is an important issue affecting the health status of newborn infants. This project strengthened the awareness of nurses regarding neonatal hypothermia and is worthwhile to be implemented in clinical neonatal care.


Subject(s)
Hypothermia/nursing , Neonatal Nursing , Humans , Hypothermia/epidemiology , Incidence , Infant, Newborn , Nursing Evaluation Research
8.
J Biomed Sci ; 16: 51, 2009 Jun 01.
Article in English | MEDLINE | ID: mdl-19486529

ABSTRACT

BACKGROUND: High levels of Hepatoma Up-Regulated Protein (HURP) and Tousled-Like Kinase (TLK) transcripts are found in hepatocellular carcinoma. HURP overexpression induces anchorage-independent growth of 293-T cells and enhances a rough-eye phenotype resulting from tlk overexpression in Drosophila. In addition, both HURP and Mars, a Drosophila HURP sequence homologue, promote polymerization of mitotic spindles. Thus, the genetic interaction of mars with tlk might be required for accurate chromosome segregation. METHODS: To reveal whether chromosome fidelity was decreased, the frequency of gynandromorphy, an individual with both male and female characteristics, and of non-disjunction were measured in the progeny from parents with reduced mars and/or tlk activities and analyzed by Student's t-test. To show that the genetic interaction between mars and tlk is epistatic or parallel, a cytological analysis of embryos with either reduced or increased activities of mars and/or tlk was used to reveal defects in mitotic-spindle morphology and chromosome segregation. RESULTS: A significant but small fraction of the progeny from parents with reduced mars activity showed gynandromorphy and non-disjunction. Results of cytological analysis revealed that the decrease in chromosome fidelity was a result of delayed polymerization of the mitotic spindle, which led to asynchronous chromosome segregation in embryos that had reduced mars activity. By removing one copy of tousled-like kinase (tlk) from flies with reduced mars activity, chromosome fidelity was further reduced. This was indicated by an increased in the non-disjunction rate and more severe asynchrony. However, the morphology of the mitotic spindles in the embryos at metaphase where both gene activities were reduced was similar to that in mars embryos. Furthermore, tlk overexpression did not affect the morphology of the mitotic spindles and the cellular localization of Mars protein. CONCLUSION: Chromosome fidelity in progeny from parents with reduced mars and/or tlk activity was impaired. The results from cytological studies revealed that mars and tlk function in parallel and that a balance between mars activity and tlk activity is required for cells to progress through mitosis correctly, thus ensuring chromosome fidelity.


Subject(s)
Chromosomes/ultrastructure , Drosophila Proteins/physiology , Drosophila melanogaster/metabolism , Gene Expression Regulation , Nerve Tissue Proteins/physiology , Protein Serine-Threonine Kinases/physiology , Amino Acid Sequence , Animals , Cell Cycle , Chromosome Segregation , Drosophila Proteins/biosynthesis , Drosophila melanogaster/genetics , Epistasis, Genetic , Humans , Models, Biological , Molecular Sequence Data , Nerve Tissue Proteins/biosynthesis , Protein Serine-Threonine Kinases/biosynthesis , Protein Structure, Tertiary , SAP90-PSD95 Associated Proteins , Sequence Homology, Amino Acid , Spindle Apparatus
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