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1.
Sci Adv ; 10(22): eadk9928, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820158

RESUMEN

The proton-electron coupling effect induces rich spectrums of electronic states in correlated oxides, opening tempting opportunities for exploring novel devices with multifunctions. Here, via modest Pt-aided hydrogen spillover at room temperature, amounts of protons are introduced into SmNiO3-based devices. In situ structural characterizations together with first-principles calculation reveal that the local Mott transition is reversibly driven by migration and redistribution of the predoped protons. The accompanying giant resistance change results in excellent memristive behaviors under ultralow electric fields. Hierarchical tree-like memory states, an instinct displayed in bio-synapses, are further realized in the devices by spatially varying the proton concentration with electric pulses, showing great promise in artificial neural networks for solving intricate problems. Our research demonstrates the direct and effective control of proton evolution using extremely low electric field, offering an alternative pathway for modifying the functionalities of correlated oxides and constructing low-power consumption intelligent devices and neural network circuits.

2.
World Neurosurg ; 185: e1086-e1092, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38490441

RESUMEN

OBJECTIVE: This study aimed to examine the mechanism of occipital condyle fractures (OCFs), their clinical symptoms, computer tomography (CT) scan findings, treatment options, and classification. METHODS: A retrospective analysis was conducted on 43 patients with OCFs who were admitted to our neurosurgery center between 2017 and 2023. RESULTS: The investigation covered their clinical symptoms, CT scan results, and treatment outcomes. It was found that 25.6% of the patients suffered from severe craniocerebral injuries with Glasgow Coma Scale (GCS) scores of 3-8 points, 9.3% had moderate injuries with GCS scores of 9-12 points, and 65.1% exhibited mild injuries with GCS scores of 13-15 points. Of these patients, 90.7% showed improvement upon discharge, 4.7% succumbed to their injuries, and another 4.7% developed paraplegia. Symptoms indicative of OCF in individuals with CCJ injuries included neck pain, swelling, cranial nerve palsy, and posterior pharyngeal wall swelling. Frequently observed complications in OCF patients included cerebral contusion, occipital bone fractures, and skull base fractures. Employing thin-layer CT scans of the CCJ area, along with sagittal and coronal CT reconstructions, is essential for identifying OCFs. The fractures were classified into 3 types based on the Anderson-Montesano classification, which, when modified, provides enhanced treatment guidance. CONCLUSIONS: OCFs are predominantly present in cases of high-energy trauma, with high-resolution thin-layer CT scans serving as the preferred diagnostic method. The application of the modified Anderson-Montesano classification, distinguishing between stable and unstable fractures, facilitates the determination of suitable treatment strategies. Stable OCFs can be managed using a rigid neck brace, while unstable OCFs may require Halo-vest frame fixation or surgical intervention.


Asunto(s)
Hueso Occipital , Humanos , Estudios Retrospectivos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Hueso Occipital/diagnóstico por imagen , Hueso Occipital/lesiones , Hueso Occipital/cirugía , Adulto Joven , Adolescente , Anciano , Tomografía Computarizada por Rayos X , Fracturas Craneales/diagnóstico por imagen , Fracturas Craneales/cirugía , Escala de Coma de Glasgow , Resultado del Tratamiento
3.
J Org Chem ; 89(2): 1083-1090, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38173188

RESUMEN

A metal-free and thiol-free organophosphorus-catalyzed method for forming thioethers was disclosed, driven by PIII/PV═O redox cycling. In this work, one-step dehydroxylative thioetherification of alcohols was fulfilled with various hypervalent organosulfur compounds. This established strategy features an excellent functional group tolerance and broad substrate scope, especially inactivated alcohols. The scale-up reaction and further transformation of the product were also successful. Additionally, this method offers a protecting-group-free and step-efficient approach for synthesizing peroxisome proliferator-activated receptor agonists which exhibited promising potential for treating osteoporosis in mammals.

4.
Mater Horiz ; 11(5): 1325-1333, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38174937

RESUMEN

Low-dimensional ferroelectric tunnel junctions are appealing for the realization of nanoscale nonvolatile memory devices due to their inherent advantages of device miniaturization. Those based on current mechanisms have limitations, including low tunneling electroresistance (TER) effects and complex heterostructures. Here, we introduce an entirely new TER mechanism to construct a nanotube ferroelectric tunnel junction with ferroelectric nanotubes as the tunneling region. When rolling a ferroelectric monolayer into a nanotube, due to the coexistence of its intrinsic ferroelectric polarization with the flexoelectric polarization induced by bending, a metal-insulator transition occurs depending on the radiative polarization states. For the pristine monolayer, its out-of-plane polarization is tunable by an in-plane electric field, and the conducting states of the ferroelectric nanotube can thus be tuned between metallic and insulating states via axial electric means. Using α-In2Se3 as an example, our first-principles density functional theory calculations and nonequilibrium Green's function formalism confirm the feasibility of the TER mechanism and indicate an ultrahigh TER ratio that exceeds 9.9 × 1010% of the proposed nanotube ferroelectric tunnel junctions. Our findings provide a promising approach based on simple homogeneous structures for high density ferroelectric microelectric devices with excellent ON/OFF performance.

5.
Orthop Surg ; 16(1): 140-148, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38086605

RESUMEN

OBJECTIVE: Ankle joint fractures are often accompanied by medial deltoid ligament rupture. There is controversy over whether or how to treat deltoid ligament rupture. This study was aimed to explore the feasibility of repairing the medial deltoid ligament using Kirschner wire internal fixation of the medial tibiotalar joint combined with external fixation. METHODS: Forty-six patients with ankle fractures involving deltoid ligament rupture, treated between October 2012 and February 2021, were retrospectively evaluated. Twenty-five patients were treated with a Kirschner wire to fix the tibiotalar joint and indirectly repair the deltoid ligament as the repaired group. Twenty-one patients underwent reduction and fixation of internal and external malleolus fractures, and the deltoid ligament was not repaired in the unrepaired group. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, visual analog scale (VAS), Medical Outcomes Short Form 36-item questionnaire score (SF-36), and Medial clear space perpendicular (preoperative, postoperative, final follow-up) were used for functional evaluations and reduction assessments. Mann-Whitney test were used to compare the differences between the groups. RESULTS: The follow-up time was 13-112 months with a mean of 59.32 months for the repaired group and 11-94 months with a mean of 53.43 months for the unrepaired group. There was no significant difference in the operative time or intraoperative blood loss between the two groups (p > 0.05). At the last follow-up, the AOFAS ankle-hindfoot and SF-36 scores of the repaired group were significantly higher than those of the non-repaired group (p < 0.05). Moreover, the VAS pain score was significantly lower and the Medial clear space perpendicular was significantly narrower in the repaired group than that in the unrepaired group. CONCLUSION: Tibiotalar joint fixation using Kirschner wires is a simple and effective technique that can indirectly reduce and repair the deltoid ligament and stabilize the ankle.


Asunto(s)
Fracturas de Tobillo , Hilos Ortopédicos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Ligamentos , Fijación Interna de Fracturas/métodos , Fracturas de Tobillo/complicaciones , Articulación del Tobillo/cirugía , Ligamentos Articulares/cirugía
6.
Medicine (Baltimore) ; 102(28): e34333, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37443507

RESUMEN

RATIONALE: To investigate the clinical efficacy of the axillary approach in the surgical treatment of Ideberg type I and II scapular glenoid fractures. PATIENT CONCERNS AND DIAGNOSIS: Retrospective analysis of 13 cases of scapular glenoid fracture treated in the affiliated Hospital of Jining Medical College, Jiaxiang County People hospital, Zoucheng City people Hospital, Yanzhou District People Hospital, and Juancheng County people Hospital from December 2020 to January 2022. Eight males (including 1 bilateral) and 5 females, with an average age of 57.5 years (range from 33 to 75 years). According to Ideberg classification, there were 10 cases of type I a, 1 case of type I a combined with type I b, and 2 cases of type II. All patients were treated with axillary approach surgery and 7 patients with combined anterior shoulder dislocation were treated by first-stage manipulation and second-stage reoperation. Seven patients were fixed with a wire anchor, 3 patients with type I a were fixed with a "T" plate, and 5 patients were complicated with rotator cuff tear and were repaired with a wire anchor. At the last follow-up, the Constant-Murley shoulder function score, visual analog score, DASH score, and Hawkins grade were used to evaluate shoulder function, pain, and stability after treatment. INTERVENTION: The intervention was to treat patients with Ideberg type I and II scaphoid fractures using an axillary approach. OUTCOMES: All 13 patients in this group were followed up thoroughly, and the follow-up time was 12 to 25 months, with an average of 18.6 months. The operation time was 65 to 135 minutes, with an average of 85.6 minutes. Intraoperative blood loss ranged from 20 to 120 mL, averaging 55.6 mL. The duration of hospitalization ranged from 7 to 22 days, with an average of 9.6 days. The surgical incisions of all patients were grade-A healing. Bone healing of glenoid fractures was observed 3 months after the operation. LESSONS: The axillary approach for Ideberg type I and II scapular glenoid fractures is a feasible surgical approach with complete access through the muscle gap, minimal surgical trauma, mild postoperative pain, and satisfactory clinical results.


Asunto(s)
Fijación Interna de Fracturas , Fracturas del Hombro , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Fijación Interna de Fracturas/métodos , Escápula/cirugía , Escápula/lesiones , Hombro/cirugía , Fracturas del Hombro/cirugía , Resultado del Tratamiento
7.
ACS Appl Energy Mater ; 6(10): 5217-5229, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37234970

RESUMEN

Monolithic perovskite/c-Si tandem solar cells have attracted enormous research attention and have achieved efficiencies above 30%. This work describes the development of monolithic tandem solar cells based on silicon heterojunction (SHJ) bottom- and perovskite top-cells and highlights light management techniques assisted by optical simulation. We first engineered (i)a-Si:H passivating layers for (100)-oriented flat c-Si surfaces and combined them with various (n)a-Si:H, (n)nc-Si:H, and (n)nc-SiOx:H interfacial layers for SHJ bottom-cells. In a symmetrical configuration, a long minority carrier lifetime of 16.9 ms was achieved when combining (i)a-Si:H bilayers with (n)nc-Si:H (extracted at the minority carrier density of 1015 cm-3). The perovskite sub-cell uses a photostable mixed-halide composition and surface passivation strategies to minimize energetic losses at charge-transport interfaces. This allows tandem efficiencies above 23% (a maximum of 24.6%) to be achieved using all three types of (n)-layers. Observations from experimentally prepared devices and optical simulations indicate that both (n)nc-SiOx:H and (n)nc-Si:H are promising for use in high-efficiency tandem solar cells. This is possible due to minimized reflection at the interfaces between the perovskite and SHJ sub-cells by optimized interference effects, demonstrating the applicability of such light management techniques to various tandem structures.

8.
Life (Basel) ; 13(5)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37240782

RESUMEN

Ascorbic acid (AA) is an indispensable nutrient required to sustain optimal poultry health and performance, which is commonly excluded from the diet of broilers. To investigate the synthesis and distribution of AA during broiler growth and clarify its possible turnover, 144 1 d old healthy Arbor Acres broilers with a body weight of approximately 41 g were randomly assigned to eight groups of 18 broilers each. The kidney, liver, ileum, and spleen of one bird from each group were collected every week until 42 d to detect the synthesis capacity, tissue distribution, and transporter gene expression of AA. The results showed that kidney L-gulonolactone oxidase (GLO) activity responded quadratically (p < 0.001), with maximum activity observed at 7 to 21 d old. Hepatic total AA and dehydroascrobate (DHA) concentration increased linearly (p < 0.001) with age, as did splenic total AA (p < 0.001). In the ileum, mRNA expression of sodium vitamin C transporter 1/2 (SVCT1/2) decreased with the growing age of the broilers (p < 0.05). The expression of SVCT1 in the kidney was not influenced by the growing age of the broilers. The progressive buildup of AA in the liver and spleen of broilers as they age implies an amplified demand for this nutrient. The waning synthesis capacity over time, however, raises concerns regarding the possible inadequacy of AA in the latter growth phase of broilers. The addition of AA to the broilers' diet might have the potential to optimize their performance. However, the effectiveness of such dietary supplementation requires further investigation.

9.
Neural Netw ; 164: 631-644, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37245477

RESUMEN

Distance metric learning has been a promising technology to improve the performance of algorithms related to distance metrics. The existing distance metric learning methods are either based on the class center or the nearest neighbor relationship. In this work, we propose a new distance metric learning method based on the class center and nearest neighbor relationship (DMLCN). Specifically, when centers of different classes overlap, DMLCN first splits each class into several clusters and uses one center to represent one cluster. Then, a distance metric is learned such that each example is close to the corresponding cluster center and the nearest neighbor relationship is kept for each receptive field. Therefore, while characterizing the local structure of data, the proposed method leads to intra-class compactness and inter-class dispersion simultaneously. Further, to better process complex data, we introduce multiple metrics into DMLCN (MMLCN) by learning a local metric for each center. Following that, a new classification decision rule is designed based on the proposed methods. Moreover, we develop an iterative algorithm to optimize the proposed methods. The convergence and complexity are analyzed theoretically. Experiments on different types of data sets including artificial data sets, benchmark data sets and noise data sets show the feasibility and effectiveness of the proposed methods.


Asunto(s)
Inteligencia Artificial , Educación a Distancia , Algoritmos , Análisis por Conglomerados , Aprendizaje
10.
J Orthop Surg Res ; 18(1): 167, 2023 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871013

RESUMEN

OBJECTIVE: To investigate the efficacy of the minimally invasive clamp reduction technique via the anterior approach in the treatment of irreducible intertrochanteric femoral fractures. METHODS: From January 2015 to January 2021, 115 patients (48 males and 67 females) with irreducible intertrochanteric femoral fractures were treated. The average age of the patients was 78.7 (45-100 years old). The types of injuries were falls (91 cases), traffic accidents (12 cases), smashing (6 cases), and high falling (6 cases). The duration between injury and surgery ranged from 1 to 14 days, with an average of 3.9 days. The distribution of AO classification was as follows: 31-A1 in 15 cases, type 31-A2 in 67 cases and 31-A3 in 33 cases. RESULTS: All patients achieved good reduction, with fracture reduction times ranging from 10 to 32 min (mean of 18 min), and were followed up for 12-27 months after surgery (mean of 17.9 months). Two patients with pronation displacement of the proximal fracture segment died of infection or hypostatic pneumonia after internal fixation failure; one patient with failed internal fixation switched to joint replacement. After internal fixation, the lateral wall of six reversed intertrochanteric femoral fractures showed repronation and abduction displacement, but all fractures achieved bony healing. The rest of the patients did not lose fracture reduction, and all fractures achieved bony healing with a healing time ranging from 3 to 9 months (mean of 5.7 months). While two patients died and one patient exhibited failed internal fixation and thus switched to joint replacement, 91 of the remaining 112 patients had an excellent Harris score of the hip joint function at the final follow-up, while 21 patients had a good Harris score. CONCLUSION: The minimally invasive clamp reduction technique via the anterior approach for the treatment of irreducible intertrochanteric femoral fractures is simple, effective and minimally invasive. In the case of irreducible intertrochanteric femoral fractures associated with lateral wall displacement, the lateral wall needs to be strengthened after clamp reduction and intramedullary nail fixation to avoid loss of reduction and failure of internal fixation.


Asunto(s)
Fracturas de Cadera , Procedimientos de Cirugía Plástica , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Accidentes de Tránsito , Fijación Interna de Fracturas , Cicatrización de Heridas , Persona de Mediana Edad
11.
Peptides ; 158: 170895, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36240981

RESUMEN

Hyperglycemia remission by metabolic surgery is implicated in the resolution of low-grade inflammation in type 2 diabetes mellitus (T2DM). However, whether this beneficial effect of metabolic surgery is related to improving monocyte inflammatory response remains undefined. This investigation is addressed to evaluate this relationship. For this purpose, T2DM rats were subjected to Roux-en-Y gastric bypass (RYGB) and/or monocyte depletion or splenic sympathetic denervation. Fasting blood glucose (FBG), plasma tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) were measured, and monocyte inflammatory response was assessed in vitro. The data showed that RYGB significantly reduced lipopolysaccharide (LPS)-induced release of TNF-α and IL-1ß from peripheral monocytes while alleviating hyperglycemia and reducing plasma TNF-α and IL-1ß levels. Hyperglycemia resulting from monocyte depletion by injection of clodronate liposomes resolved one week earlier than vehicle control after RYGB. Splenic denervation abrogated the glucose-lowering effect and decreased LPS-stimulated TNF-α and IL-1ß release from monocytes following RYGB. Overall, our results reveal that a marked reduction of monocyte inflammatory response after RYGB contributes to hyperglycemia remission in T2DM rats. The beneficial effect of RYGB is mediated through vagal-spleen axis anti-inflammatory activity.


Asunto(s)
Diabetes Mellitus Tipo 2 , Derivación Gástrica , Hiperglucemia , Ratas , Animales , Derivación Gástrica/métodos , Diabetes Mellitus Tipo 2/metabolismo , Monocitos/metabolismo , Lipopolisacáridos , Factor de Necrosis Tumoral alfa , Glucemia/metabolismo
12.
Neural Netw ; 154: 165-178, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35882084

RESUMEN

Multi-metric learning plays a significant role in improving the generalization of algorithms related to distance metrics since using a single metric is sometimes insufficient to handle complex data. Metric learning can adjust automatically the distance between samples to make the intra-class samples compact while making the inter-class distance as far as possible. To implement this intention better,in this work, we propose a novel multi-metric learning framework based on the pair constraints instead of triple constraints to reduce computational burden. To solve effectively the problem, we first propose a multi-birth metric learning model (termed MBML), where for each class sample, the global metric and a local metric are jointly trained. Both global and local structural information are adapted to better depict sample information. Then two alternating iterative algorithms are developed to optimize the MBML. The convergence of the proposed algorithm and complexity are analyzed theoretically. Moreover, a fast diagonal multi-metric learning method is proposed based on binary constraints, and problem can be reformulated a linear programming, with fast training speed, low the computational burden and the global optimal solutions. Numerical experiments are carried out on different scales and different types of datasets including an artificial data, benchmark datasets and an image database from binary class and multi-class problems. Experiment results confirm the feasibility and effectiveness of the proposed methods.


Asunto(s)
Inteligencia Artificial , Reconocimiento de Normas Patrones Automatizadas , Algoritmos , Bases de Datos Factuales , Aprendizaje , Reconocimiento de Normas Patrones Automatizadas/métodos
13.
Nano Lett ; 22(12): 4792-4799, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35639474

RESUMEN

HfO2-based films with high compatibility with Si and complementary metal-oxide semiconductors (CMOS) have been widely explored in recent years. In addition to ferroelectricity and antiferroelectricity, flexoelectricity, the coupling between polarization and a strain gradient, is rarely reported in HfO2-based films. Here, we demonstrate that the mechanically written out-of-plane domains are obtained in 10 nm Hf0.5Zr0.5O2 (HZO) ferroelectric film at room temperature by generating the stress gradient via the tip of an atomic force microscope. The results of scanning Kelvin force microscopy (SKPM) exclude the possibility of flexoelectric-like mechanisms and prove that charge injection could be avoided by mechanical writing and thus reveal the true polarization state, promoting wider flexoelectric applications and ultrahigh-density storage of HZO thin films.

14.
J Phys Condens Matter ; 34(20)2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35193130

RESUMEN

Spin-orbit coupling (SOC) plays an important role in condensed matter physics and has potential applications in spintronics devices. In this paper, we study the electronic properties of ferroelectric CuInP2S6(CIPS) monolayer through first-principles calculations. The result shows that CIPS monolayer is a potential for valleytronics material and we find that the in-plane helical and nonhelical pseudospin texture are induced by the Rashba and Dresselhaus effect, respectively. The chirality of helical pseudospin texture is coupled to the out-of-plane ferroelectric polarization. Furthermore, a large spin splitting due to the SOC effect can be found atKvalley, which can be regarded as the Zeeman effect under a valley-dependent pseudomagnetic field. The CIPS monolayer with Rashbaet aleffects provides a good platform for electrically controlled spin polarization physics.

15.
Mol Med Rep ; 25(4)2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35191523

RESUMEN

It is known that increased inflammation and extracellular matrix (ECM) degradation in chondrocytes can promote the development of osteoarthritis (OA). The FXYD domain containing ion transport regulator 5 (Fxyd5) has been found to promote chronic inflammatory responses. The present study aimed to investigate the role of Fxyd5 in OA. Murine ATDC5 chondrocytes were transfected with short hairpin RNAs specifically targeting Fxyd5 to silence its expression. Subsequently, cells were induced with lipopolysaccharide (LPS). The protein expression levels of Fxyd5, MMPs and proteins related to ECM, apoptosis and NF­κB signaling were detected using western blot analysis. In addition, cell viability was assessed using a Cell Counting Kit­8 assay, while the secretion of the proinflammatory factors and those of the oxidative stress­related markers were measured using the corresponding kits. Finally, cells were treated with the NF­κB activator, betulinic acid (BA) and the above experiments were repeated. The results demonstrated that Fxyd5 was significantly upregulated in ATDC5 cells treated with LPS. Additionally, Fxyd5 knockdown increased cell viability, enhanced the protein expression of Bcl­2, Aggrecan and collagen II, while reduced the expression of Bax, cleaved caspase­3/caspase­3, MMP3 and MMP13 in LPS­induced ATDC5 cells. The production of IL­1ß, IL­6 and IL­18 as well as reactive oxygen species and malondialdehyde, and the reduction of superoxide dismutase caused by LPS in ATDC5 cells, were also reversed by Fxyd5 silencing. Fxyd5 silencing inhibited the phosphorylation of p65 and IκBα induced by LPS. Finally, BA reversed the protective effect of Fxyd5 silencing on LPS induced chondrocytes injury. In conclusion, Fxyd5 could enhance chondrocyte inflammation and ECM degradation via activating the NF­κB signaling.


Asunto(s)
Condrocitos , Osteoartritis , Animales , Apoptosis , Condrocitos/metabolismo , Matriz Extracelular/metabolismo , Inflamación/metabolismo , Lipopolisacáridos/efectos adversos , Ratones , FN-kappa B/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo
16.
ACS Nano ; 16(1): 1308-1317, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-34978807

RESUMEN

Searching van der Waals ferroic materials that can work under ambient conditions is of critical importance for developing ferroic devices at the two-dimensional limit. Here we report the experimental discovery of electric-field-induced reversible antiferroelectric (AFE) to ferroelectric (FE) transition at room temperature in van der Waals layered α-GeSe, employing Raman spectroscopy, transmission electron microscopy, second-harmonic generation, and piezoelectric force microscopy consolidated by first-principles calculations. An orientation-dependent AFE-FE transition provides strong evidence that the in-plane (IP) polarization vector aligns along the armchair rather than zigzag direction in α-GeSe. In addition, temperature-dependent Raman spectra showed that the IP polarization could sustain up to higher than 700 K. Our findings suggest that α-GeSe, which is also a potential ferrovalley material, could be a robust building block for creating artificial 2D multiferroics at room temperature.

17.
Phys Chem Chem Phys ; 23(47): 26997-27004, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34842874

RESUMEN

Among the IV-VI compounds, GeSe has wide applications in nanoelectronics due to its unique photoelectric properties and adjustable band gap. Even though modulation of its physical characteristics, including the band gap, by an external field will be useful for designing novel devices, experimental work is still rare. Here, we report a detailed anisotropic Raman response of GeSe flakes under uniaxial tension strain. Based on theoretical analysis, the anisotropy of the phonon response is attributed to a change in anisotropic bond length and bond angle under in-plane uniaxial strain. An enhancement in anisotropy and band gap is found due to strain along the ZZ or AC directions. This study shows that strain-engineering is an effective method for controlling the GeSe lattice, and paves the way for modulating the anisotropic electric and optical properties of GeSe.

18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(9): 1086-1092, 2021 Sep 15.
Artículo en Chino | MEDLINE | ID: mdl-34523271

RESUMEN

OBJECTIVE: To formulate the classification criteria of femoral intertrochanteric fractures based on irreducibility or not in order to predict the difficulty of fracture recovery. METHODS: A clinical data of 244 patients with closed femoral intertrochanteric fractures admitted between January 2017 and March 2020 was retrospectively analyzed. There were 116 males and 128 females with an average age of 77.9 years (range, 45-100 years). The cause of injury included falling in 190 cases, traffic accident in 36 cases, smashing in 13 cases, and falling from height in 5 cases. The time from injury to operation was 1-14 days (mean, 3.6 days). According toAO/Orthopaedic Trauma Association (AO/OTA) classification, the fractures were classified as type 31-A1 in 38 cases, type 31-A2 in 160 cases, and type 31-A3 in 46 cases. According to whether the recovery difficulty occurred after intraoperative closed traction reset, the patients were divided into reducible-group and irreducible-group; combined with the literature and preoperative imaging data of two groups, the classification criteria of femoral intertrochanteric fractures was formulated based on the irreducibility or not. The 244 fractures were classified by the doctors who did not attend the operation according to the classification criteria, predicted the difficulty of fracture reduction, and compared with the actual intraoperative reduction situation. RESULTS: The 244 patients were divided into reducible-group ( n=164, 67.21%) and irreducible-group ( n=80, 32.79%) according to the intraoperative difficulty of reduction. Comparing the imaging data and characteristics of the two groups, and formulating the classification criteria of femoral intertrochanteric fractures based on irreducibility or not, the fractures were mainly divided into two categories of irreducibility and reducibility. The fractures of irreducibility category was divided into typesⅠ-Ⅴ, among which type Ⅲ was divided into subtypes 1-4; the fractures of reducibility category was divided into typesⅠand Ⅱ. Compared with the actual intraoperative evaluation results, the total accuracy rate of the doctors who did not attend the operation was 81.15% (198/244) based on the classification criteria of femoral intertrochanteric fractures. The accuracy rate of irreducibility category was 65.74% (71/108), and the reducibility category was 93.38% (127/136). All patients were followed up 13-25 months, with an average of 17.6 months. All fractures healed except 2 cases died of infection. CONCLUSION: The classification criteria of femoral intertrochanteric fractures based on irreducibility or not can accurately predict the reducible cases preoperatively, and most of the irreducible cases can be correctly predicted in a wider way. But the classification criteria still need to be further improved and supplemented.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Fracturas de Cadera , Anciano , Clavos Ortopédicos , Femenino , Fracturas del Fémur/cirugía , Fracturas de Cadera/cirugía , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
19.
Front Genet ; 12: 676917, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34108995

RESUMEN

Guangdong province is situated in the south of China with a population size of 113.46 million. Hakka is officially recognized as a branch of Han Chinese, and She is the official minority group in mainland China. There are approximately 25 million Hakka people who mainly live in the East and North regions of China, while there are only 0.7 million She people. The genetic characterization and forensic parameters of these two groups are poorly defined (She) or still need to be explored (Hakka). In this study, we have genotyped 475 unrelated Guangdong males (260 Hakka and 215 She) with Promega PowerPlex® Y23 System. A total of 176 and 155 different alleles were observed across all 23 Y-STRs for Guangdong Hakka (with a range of allele frequencies from 0.0038 to 0.7423) and Guangdong She (0.0047-0.8605), respectively. The gene diversity ranged from 0.4877 to 0.9671 (Guangdong Hakka) and 0.3277-0.9526 (Guangdong She), while the haplotype diversities were 0.9994 and 0.9939 for Guangdong Hakka and Guangdong She, with discrimination capacity values of 0.8885 and 0.5674, respectively. With reference to geographical and linguistic scales, the phylogenetic analyses showed us that Guangdong Hakka has a close relationship with Southern Han, and the genetic pool of Guangdong Hakka was influenced by surrounding Han populations. The predominant haplogroups of the Guangdong She group were O2-M122 and O2a2a1a2-M7, while Guangdong She clustered with other Tibeto-Burman language-speaking populations (Guizhou Tujia and Hunan Tujia), which shows us that the Guangdong She group is one of the branches of Tibeto-Burman populations and the Huonie dialect of She languages may be a branch of Tibeto-Burman language families.

20.
Comput Math Methods Med ; 2021: 9967592, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34055043

RESUMEN

Due to the complexity of human emotions, there are some similarities between different emotion features. The existing emotion recognition method has the problems of difficulty of character extraction and low accuracy, so the bidirectional LSTM and attention mechanism based on the expression EEG multimodal emotion recognition method are proposed. Firstly, facial expression features are extracted based on the bilinear convolution network (BCN), and EEG signals are transformed into three groups of frequency band image sequences, and BCN is used to fuse the image features to obtain the multimodal emotion features of expression EEG. Then, through the LSTM with the attention mechanism, important data is extracted in the process of timing modeling, which effectively avoids the randomness or blindness of sampling methods. Finally, a feature fusion network with a three-layer bidirectional LSTM structure is designed to fuse the expression and EEG features, which is helpful to improve the accuracy of emotion recognition. On the MAHNOB-HCI and DEAP datasets, the proposed method is tested based on the MATLAB simulation platform. Experimental results show that the attention mechanism can enhance the visual effect of the image, and compared with other methods, the proposed method can extract emotion features from expressions and EEG signals more effectively, and the accuracy of emotion recognition is higher.


Asunto(s)
Aprendizaje Profundo , Electroencefalografía/métodos , Emociones/fisiología , Inteligencia Artificial , Atención/fisiología , Biología Computacional , Simulación por Computador , Electroencefalografía/estadística & datos numéricos , Expresión Facial , Humanos
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