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A metal-free and thiol-free organophosphorus-catalyzed method for forming thioethers was disclosed, driven by PIII/PVâO 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.
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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.
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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.
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INTRODUCTION: The objective of this meta-analysis was to systematically assess the association between periodontal disease (PD) and myocardial infarction (MI). METHODS: We searched the EMBASE, PubMed, and Cochrane Library databases for eligible cohort studies from inception to August 31st, 2020 that reported the association between PD and MI. Data extraction was conducted after screening the literature. The risk of bias of the included studies was evaluated by using the Newcastle-Ottawa Scale (NOS). The combined OR value and 95% confidence interval (CI) were calculated by using STATA 11.0 software, and the source of any heterogeneity was determined by performing subgroup analysis and sensitivity analysis. RESULTS: A total of 10 cohort studies involving 5,369,235 participants fulfilled the inclusion criteria. The meta-analysis showed an increased risk for MI in patients with PD [RR = 1.13, 95% CI (1.04, 1.21), P = 0.004], and this result was robust according to sensitivity analysis. Subgroup analyses indicated that the results were affected by sex, effect value, study quality, survey form and investigation type. DISCUSSION: This meta-analysis suggests that PD is modestly associated with MI, especially in women, which is similar to the conclusions of earlier meta-analyses of case-control or observational studies. PD may be an untraditional risk factor for cardiovascular diseases, including MI; thus, maintaining periodontal health may be an effective measure to prevent MI. More cohort studies are still needed to further explore the relationship between the incidence of MI and PD.
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Infarto do Miocárdio/etiologia , Doenças Periodontais/complicações , Estudos de Coortes , Humanos , Razão de Chances , Fatores de RiscoRESUMO
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.
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Osso Occipital , Humanos , Estudos Retrospectivos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Osso Occipital/diagnóstico por imagem , Osso Occipital/lesões , Osso Occipital/cirurgia , Adulto Jovem , Adolescente , Idoso , Tomografia Computadorizada por Raios X , Fraturas Cranianas/diagnóstico por imagem , Fraturas Cranianas/cirurgia , Escala de Coma de Glasgow , Resultado do TratamentoRESUMO
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.
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Fraturas do Tornozelo , Fios Ortopédicos , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Ligamentos , Fixação Interna de Fraturas/métodos , Fraturas do Tornozelo/complicações , Articulação do Tornozelo/cirurgia , Ligamentos Articulares/cirurgiaRESUMO
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.
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BACKGROUND: In the early stages of diabetic kidney disease (DKD), the pathogenesis involves abnormal angiogenesis in the glomerulus. Hirudin, as a natural specific inhibitor of thrombin, has been shown in previous studies to inhibit the migration of various tumor endothelial cells and abnormal angiogenesis. However, its role in DKD remains unclear. METHODS: The effects of hirudin in DKD were studied using spontaneous type 2 diabetic db/db mice (which develop kidney damage at 8 weeks). Network pharmacology was utilized to identify relevant targets. An in vitro high glucose model was established using mouse glomerular endothelial cells (MGECs) to investigate the effects of hirudin on the migration and angiogenic capacity of MGECs. RESULTS: Hirudin can ameliorate kidney damage in db/db mice. Network pharmacology suggests its potential association with the VEGFA/VEGFR2 pathway. Western blot and immunohistochemistry demonstrated elevated protein expression levels of VEGFA, VEGFR2, AQP1, and CD31 in db/db mice, while hirudin treatment reduced their expression. In the MGECs high glucose model, hirudin may reverse the enhanced migration and angiogenic capacity of MGECs in a high glucose environment by altering the expression of VEGFA, VEGFR2, AQP1, and CD31. Moreover, the drug effect gradually increases with higher concentrations of hirudin. CONCLUSIONS: This study suggests that hirudin can improve early-stage diabetic kidney disease kidney damage by inhibiting the migration and angiogenesis of glomerular endothelial cells, thereby further expanding the application scope of hirudin. Additionally, the study found increased expression of AQP1 in DKD, providing a new perspective for further research on the potential pathogenesis of DKD.
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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.
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Echinococcus granulosus, the etiologic agent of cystic echinococcosis in humans and other animal hosts, is distributed worldwide. Echinococcosis is an increasing public health and socioeconomic concern. The present work evaluated whether or not a superabsorbent polymer (SAP) could enhance the damage efficacy of high-intensity focused ultrasound (HIFU) on the viability of E. granulosus protoscolices in vitro. HIFU of 100 W acoustic power and 0.01 g superabsorbent polymer were used to treat 5,000 protoscolices in 2-ml protoscolices suspension. After different HIFU exposure time (5, 10, 20, 30, 40, 50, and 60 s, respectively), the temperature of protoscolices suspension was taken, and the treated protoscolices were stained by trypan-blue exclusion assay, and their structures were observed by light microscopy. To better understand the biological mechanisms responsible for the deaths of protoscolices, the activity of succinate dehydrogenase (SDH) of the protoscolices treated with HIFU was examined. The temperature of protoscolices suspension treated with HIFU rose slowly, and the death rate of protoscolices was 73.7 % in the group of HIFU treatment time of 40 s; however, with the same HIFU treatment time of 40 s, the temperature of protoscolices suspension in the group of HIFU combined with SAP rose quickly, and the death rate of protoscolices was 100 %. The same protoscolicidal effect (100 %) of HIFU of 100 W acoustic power combined with SAP was also observed in the groups of HIFU treatment time of 50 and 60 s, respectively. The dead protoscolices were stained to blue, shrunken and black calcareous corpuscles, and disordered and decreasing hooks though of intact membrane, as well as some protoscolices lost hooks and tore open on membrane were observed. In the group of HIFU combined with SAP, it was found that the superabsorbent polymer was surrounded by the spoiled, and the destruction of protoscolices was much stronger than in the group of HIFU. The dead protoscolices exhibited the reduction or absence of SDH staining intensity in the parenchymal cell and calcareous corpuscles after HIFU irradiation, where a large number of necrotic cells were evident. These results suggested that HIFU could induce the damage and loss of viability of protoscolices; SAP could enhance the HIFU energy focused and cause more severe destruction efficacy on protoscolices; and mitochondrial energetic function is involved in the regulation of cell-death pathways of protoscolices.
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Anti-Helmínticos/toxicidade , Echinococcus granulosus/efeitos dos fármacos , Echinococcus granulosus/fisiologia , Polímeros/toxicidade , Som , Animais , Echinococcus granulosus/anatomia & histologia , Microscopia , Succinato Desidrogenase/análise , Análise de Sobrevida , TemperaturaRESUMO
Cystic echinococcosis, caused by the metacestode stage of Echincoccus granulosus, remains endemic in many regions around the world. The present work evaluated whether or not a superabsorbent polymer (SAP) and ultrasound contrast agent (UCA) alone or in combination could enhance damage efficacy of high-intensity focused ultrasound (HIFU) on hydatid cysts in vitro. HIFU of 100 W acoustic power, with the aid of 0.1 ml UCA and 0.1 g SAP alone or in combination, was used to ablate hydatid cysts in vitro. The comparison of ultrasound image for each layer of hydatid cyst before and after HIFU ablation was made immediately, and the protoscolices of the cysts were stained by eosin exclusion assay, and the structures of protoscolices were observed by light microscopy. To understand the destructive effects of HIFU, the pathological changes in cyst walls of hydatid cyst ablated with HIFU were examined. The results demonstrated that HIFU had some lethal effect on hydatid cysts: echo enhancement of ultrasound image, increase of mortality rate of protoscolices, serious structural damage of protoscolices, and complete destruction or even disappearance of laminated layer and germinal layer was observed in the group of HIFU combined with UCA and SAP alone or in combination. It was found that the destructive effect of HIFU aided with a combination of UCA and SAP to hydatid cysts was more effective than that of HIFU just aided with UCA or SAP alone. These results suggested that UCA and SAP might be used as a HIFU enhancing agent to improve the efficacy of HIFU ablation to hydatid cysts, which could be a possible therapeutic option for cystic echinococcosis.
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Anti-Helmínticos/farmacologia , Meios de Contraste/farmacologia , Equinococose/diagnóstico por imagem , Echinococcus granulosus/efeitos dos fármacos , Sonicação/métodos , Animais , Equinococose/patologia , Echinococcus granulosus/anatomia & histologia , Ondas de Choque de Alta Energia , Microscopia , Análise de Sobrevida , UltrassonografiaRESUMO
The present study investigates the damages of high intensity focused ultrasound (HIFU) to transplanted hydatid cysts in abdominal cavities of rabbits with aids of ultrasound contrast agent (UCA) and superabsorbent polymer (SAP) alone or in combination. A rabbit model with transplanted hydatid cyst was established by implanting hydatid cyst isolated from infected sheep liver, and HIFU was used to ablate the transplanted cysts with the aid of UCA and SAP alone or in combination. The hydatid cyst with thin wall, good elasticity, approximately spherical, and a diameter of approximately 30 mm was selected for the following experiments. According to our previous studies, a mixture of 0.1 g SAP and 0.5 ml anhydrous ethanol, and the solution of 0.1 ml UCA SonoVue, or both materials were injected into different cyst before HIFU ablation, respectively. The cyst inoculated with the SAP and UCA alone or in combination was immediately implanted into the abdominal cavity of rabbit for HIFU ablation at a dosage of 100 W acoustic powers. The ablation mode was spot scanning at the speed of 3 mm/s. Every target point was scanned three times; every ablating time lasted 3 s. The distance of each ablated layer was 5 mm. The total ablation time depended on the volume of cyst. The comparison of ultrasound image for each layer of hydatid cyst was made before and after HIFU ablation. The protoscolices in ablated cysts were stained by trypan blue exclusion assay, and their structures were observed by light microscopy. To estimate ablation effects of HIFU to the walls of hydatid cysts, the ultrastructure changes of cyst walls were examined by electron microscopy. The pathological changes of rabbits' skins through which ultrasound penetrated were observed to investigate the side effects of HIFU ablation. The results demonstrated that HIFU had some lethal effects to hydatid cysts in vivo, namely, echo enhancements of ultrasound images of cysts, increases in mortality rate of protoscolices from 15.19 % (HIFU alone) to 48.66 % (HIFU + SAP), 38.67 % (HIFU + UCA), and 67.75 % (HIFU + SAP + UCA), respectively, serious structural damages of protoscolices, and destructions or even disappearance of laminated layers and germinal layers in the walls of hydatid cysts ablated by HIFU aided with UCA and SAP alone or in combination. This study demonstrated that destructive effects of HIFU to transplanted hydatid cyst could be enhanced by UCA and SAP alone, but the destruction of HIFU aided with a combination of UCA and SAP to hydatid cysts was more effective than those aided with UCA or SAP alone. The enhanced thermal and cavitation effects of HIFU induced by UCA and SAP might be involved in the enhanced destructive effects of HIFU on hydatid cysts. There were no evidences of pathological changes on rabbits' skins overlying the hydatid cysts after HIFU ablation. The results suggested that the rabbit model with transplanted hydatid cyst may serve as an optional animal model for the experiments of HIFU ablation to hydatid cyst in vivo, and the materials of UCA and SAP were proved as enhancing agents of HIFU ablation to hydatid cysts, and HIFU at a dosage of 100 W acoustic powers was a safe and feasible parameter to ablate the hydatid cysts in this special animal model. These results laid a theoretical foundation for improving HIFU therapy for cystic echinococcosis by inoculation of UCA and SAP into hydatid cysts.
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Cavidade Abdominal/diagnóstico por imagem , Anti-Helmínticos/farmacologia , Meios de Contraste/farmacologia , Equinococose/diagnóstico por imagem , Echinococcus granulosus/efeitos dos fármacos , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Polímeros/farmacologia , Cavidade Abdominal/parasitologia , Cavidade Abdominal/patologia , Animais , Anti-Helmínticos/administração & dosagem , Meios de Contraste/administração & dosagem , Modelos Animais de Doenças , Equinococose/patologia , Echinococcus granulosus/ultraestrutura , Ablação por Ultrassom Focalizado de Alta Intensidade/estatística & dados numéricos , Humanos , Polímeros/administração & dosagem , Coelhos , Resultado do Tratamento , UltrassonografiaRESUMO
This study evaluated whether or not a superabsorbent polymer (SAP) combined with ultrasound contrast agent (UCA) could enhance damage efficacy of high intensity focused ultrasound (HIFU) on Echinococcus granulosus protoscoleces in vitro. Thirty test tubes each with 6 000-7 500 protoscolices were divided into 5 groups: group A (blank control) without HIFU treatment, group B treated with HIFU (50 W) only, group C treated with 10 microl UCA and HIFU, group D treated with 0.01 g SAP and HIFU, group E treated with 10 microl UCA, 0.01 g SAP, and HIFU. In group B, echo enhancement of ultrasound image, suspension temperature (26.0 degrees C +/- 0.2 degrees C) and protoscoleces mortality (30.4%) were higher than that of group A (18.0 degrees C +/- 0.1 degrees C, 1.9%) (P < 0.01). Compared with group B, the echo enhancement of ultrasound image, suspension temperature (27.0 degrees C +/- 0.2 degrees C, 28.2 degrees C +/- 0.2 degrees C) and protoscoleces mortality (50.0%, 53.7%) of groups C and D increased significantly (P < 0.01). In group E, more protoscoleces were stained in red and their internal structures were indistinct. By chi-square test, the protoscoleces mortality of group E (69.7%) was higher than that of groups C and D (P < 0.01). There was no significant difference in suspension temperature among the 3 groups.
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Meios de Contraste/farmacologia , Echinococcus granulosus/efeitos dos fármacos , Polímeros/farmacologia , Ultrassom , AnimaisRESUMO
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.
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Inteligência Artificial , Educação a Distância , Algoritmos , Análise por Conglomerados , AprendizagemRESUMO
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.
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Fraturas do Quadril , Procedimentos de Cirurgia Plástica , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Acidentes de Trânsito , Fixação Interna de Fraturas , Cicatrização , Pessoa de Meia-IdadeRESUMO
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.
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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.
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Fixação Interna de Fraturas , Fraturas do Ombro , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Fixação Interna de Fraturas/métodos , Escápula/cirurgia , Escápula/lesões , Ombro/cirurgia , Fraturas do Ombro/cirurgia , Resultado do TratamentoRESUMO
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.
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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.
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Inteligência Artificial , Reconhecimento Automatizado de Padrão , Algoritmos , Bases de Dados Factuais , Aprendizagem , Reconhecimento Automatizado de Padrão/métodosRESUMO
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.