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The design of immunogens that elicit broadly reactive neutralizing antibodies (bnAbs) has been a major obstacle to HIV-1 vaccine development. One approach to assess potential immunogens is to use mice expressing precursors of human bnAbs as vaccination models. The bnAbs of the VRC01-class derive from the IGHV1-2 immunoglobulin heavy chain and neutralize a wide spectrum of HIV-1 strains via targeting the CD4 binding site of the envelope glycoprotein gp120. We now describe a mouse vaccination model that allows a germline human IGHV1-2(∗)02 segment to undergo normal V(D)J recombination and, thereby, leads to the generation of peripheral B cells that express a highly diverse repertoire of VRC01-related receptors. When sequentially immunized with modified gp120 glycoproteins designed to engage VRC01 germline and intermediate antibodies, IGHV1-2(∗)02-rearranging mice, which also express a VRC01-antibody precursor light chain, can support the affinity maturation of VRC01 precursor antibodies into HIV-neutralizing antibody lineages.
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Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , VIH-1/inmunología , Inmunización , Cadenas Pesadas de Inmunoglobulina/inmunología , Células Precursoras de Linfocitos B/inmunología , Animales , Anticuerpos Monoclonales/genética , Linfocitos B/inmunología , Anticuerpos ampliamente neutralizantes , Línea Celular , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/inmunología , Anticuerpos Anti-VIH , Cadenas Pesadas de Inmunoglobulina/química , Cadenas Pesadas de Inmunoglobulina/genética , Concentración 50 Inhibidora , Ratones , Eliminación de Secuencia , Linfocitos T/inmunologíaRESUMEN
PURPOSE: PSMA/PET has been increasingly used to detect PCa, and PSMA/PET-guided biopsy has shown promising results. However, it cannot be confirmed immediately whether the tissues are the targeted area. In this study, we aimed to develop a novel probe, [123I]I-PSMA-7. First, we hope that [123I]I-PSMA-7 can provide instant confirmation for prostate biopsy. Second, we hope it will help detect PCa. METHODS: We synthesized a high-affinity probe, [123I]I-PSMA-7, and evaluated its properties. We included ten patients with suspected PCa and divided them into two groups. The injection and biopsy were approximately 24 h apart. The activity in biopsy lesions was measured as the cpm by a γ-counter. Moreover, we enrolled 3 patients to evaluate the potential of [123I]I-PSMA-7 for detecting PCa. RESULTS: Animal experiments verified the safety, targeting and effectiveness of [123I]I-PSMA-7, and the tumor-to-muscle ratio was greatest at 24 h, which confirmed the results of this study in humans. After injection of 185MBq [123I]I-PSMA-7, 18/55 cores were positive, and the cpm was significantly greater (4345 ± 3547 vs. 714 ± 547, P < 0.001), with an AUC of 0.97 and a cutoff of 1312 (sens/spec of 94.40%/91.90%). At a lower dose, 10/55 biopsy cores were cancerous, and the cpm was 2446 ± 1622 vs. 153 ± 112 (P < 0.001). The AUC was 1, with a cutoff value of 490 (sens/spec of 100%). When the radiopharmaceuticals were added to 370 MBq, we achieved better SPECT/CT imaging. CONCLUSION: With the aid of [123I]I-PSMA-7 and via cpm-based biopsy, we can reduce the number of biopsies to a minimum operation. [123I]I-PSMA-7 PSMA SPECT/CT can also provide good imaging results. TRIAL REGISTRATION: Chinese Clinical trial registry ChiCTR2300069745, Registered 24 March 2023.
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Intravenous thrombolysis (IVT) and dual antiplatelet therapy (DAPT) have been widely used in minor ischemic stroke (MIS) treatment. However, the clinical outcomes and safety of these two treatments have not been compared within the early thrombolytic time window. Here, we conducted a multicenter, ambispective cohort study involving patients with MIS presenting within 4.5 h of symptom onset at 3 affiliated hospitals of Jinan University from 2018-2022. The patients were divided into the IVT group and DAPT group. The primary outcome was a 90-day excellent outcome (mRS ≤ 1). A total of 1,026 patients were enrolled, of whom 492 were assigned to the IVT group and 534 were assigned to the DAPT group. The IVT group had better 90-day excellent outcomes (mRS ≤ 1) than the DAPT group (OR 1.69, 95% CI 1.14-2.52, P = 0.010). Among the 623 patients with nondisabling stroke, the proportion of mRS ≤ 1 in the IVT group was higher than the DAPT group (P = 0.009). In the subtypes of MIS with large vessel occlusion/stenosis and with isolated symptoms, the 90-day outcomes of the IVT group and DAPT group were not different (P > 0.05). In conclusion, compared with DAPT, IVT was associated with better 90-day clinical outcomes in patients with MIS (in particular, for those with mRS > 1), including earlier clinical improvement.IVT also benefited the early neurological improvement of patients with severe stenosis/occlusion of intracranial large vessels, nondisabling mild stroke, nondisabling mild stroke with isolated symptoms.
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BACKGROUND The evidence on use of supplementary titanium cable cerclage (TCC) in treating femoral subtrochanteric fractures (FSF) remains scarce. Therefore, this study aimed to investigate the potential therapeutic effects for FSF patients using TCC. MATERIAL AND METHODS A retrospective study of 68 FSF patients treated by a long intramedullary (IM) nailing with (Observation group, n=41) or without (Control group, n=27) TCC was conducted from January 2020 to December 2021. The primary outcome measure was time to postoperative full weight-bearing. Secondary outcome measures were operation time, intraoperative blood loss, number of blood transfusions needed, varus angle loss, excellent and good rate of fracture reduction, Harris score, and survival rate. RESULTS Patients were followed up for 13 to 36 months. The excellent and good rate of fracture reduction was 100% in the Observation group versus 92.6% in the Control group (P=0.013), and the varus angle loss and time to postoperative full weight-bearing in the Observation group were significantly less than in the Control group (P<0.05). The intraoperative blood loss in the Observation group was significantly higher than in the Control group (P<0.001). No differences were noted between groups for Harris scores and survival rates at last follow-up. CONCLUSIONS TCC fixation combined with IM nailing can improve the excellent and good rate of fracture reduction and reduce varus angle loss, as well as shorten the time to full weight-bearing and promote early functional exercise, which offers an effective treatment option for FSF patients who have failed closed reduction.
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Clavos Ortopédicos , Fijación Intramedular de Fracturas , Fracturas de Cadera , Titanio , Humanos , Femenino , Estudios Retrospectivos , Masculino , Fijación Intramedular de Fracturas/métodos , Anciano , Fracturas de Cadera/cirugía , Resultado del Tratamiento , Persona de Mediana Edad , Fracturas del Fémur/cirugía , Anciano de 80 o más Años , Soporte de PesoRESUMEN
BACKGROUND It is unclear whether preoperative thyroid-stimulating hormone (TSH) level is correlated with long-term mortality in the elderly after hip fracture surgery. We aimed to assess the association between TSH levels and 3-year mortality in these patients. MATERIAL AND METHODS We enrolled patients aged 65 and above who had hip fracture surgery and thyroid function tests upon admission from 2018 to 2019. Patients were categorized based on TSH median value, quartiles, or thyroid function status. The median follow-up time was 3.1 years. Cox proportional hazards models were used to examine the correlation between TSH levels and mortality, adjusting for covariates. RESULTS Out of 799 eligible patients, 92.7% (741/799) completed the follow-up, with 20.6% (153/741) of those having died by the end of the follow-up. No statistically significant differences in mortality risks were found when stratified by TSH median value (HR 0.88, 95% CI 0.64-1.22, P=0.448) or quartiles (HR ranging from 0.90 to 1.13, P>0.05). Similarly, when categorized based on admission thyroid function status, patients who presented with hypothyroidism, subclinical hypothyroidism, hyperthyroidism, and subclinical hyperthyroidism upon admission did not demonstrate a statistically significant difference in mortality risk compared to those who were considered euthyroid (HR 1.34, 95% CI 0.72-2.49, P=0.359; HR 0.77, 95% CI 0.38-1.60, P=0.489; HR 1.15, 95% CI 0.16-8.30, P=0.890; HR 1.07, 95% CI 0.34-3.38, P=0.913, respectively). CONCLUSIONS Admission TSH is not significantly associated with 3-year mortality in geriatric patients after hip fracture surgery.
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Fracturas de Cadera , Tirotropina , Humanos , Fracturas de Cadera/mortalidad , Fracturas de Cadera/cirugía , Fracturas de Cadera/sangre , Anciano , Masculino , Tirotropina/sangre , Femenino , Estudios Prospectivos , Anciano de 80 o más Años , Pruebas de Función de la Tiroides , Modelos de Riesgos Proporcionales , Periodo Preoperatorio , Factores de Riesgo , Hipotiroidismo/sangre , Hipotiroidismo/mortalidad , Hipertiroidismo/sangre , Hipertiroidismo/mortalidadRESUMEN
INTRODUCTION: Endovascular thrombectomy (EVT) is the standard of care for patients with large-vessel occlusion acute ischemic stroke (AIS). There may be differing recanalization effectiveness based on patients' sex, and understanding such variations can improve patient outcomes by adjusting for differences. We aimed to assess the sex differences in outcome after EVT for patients with AIS. METHODS: We retrospectively analyzed 250 consecutive AIS patients who underwent EVT from July 2019 to February 2022 across two large comprehensive tertiary care stroke centers in China. Outcomes of male patients were compared to females, where poor outcome was defined as a modified Rankin score (mRS) of 3-6 at 90 days. RESULTS: Male patients had higher rates of symptomatic intracranial hemorrhage (sICH) (12.50% vs. 4.05%, p = 0.042) and higher hospitalization costs (114,541.08 vs. 105,790.27 RMB, p = 0.024). Male patients also had a longer median onset-to-needle time (ONT) (146.00 [104.00, 202.00] versus 120.00 [99.25, 144.75], p = 0.026). However, there were no differences in hospitalization length (p = 0.251), 90-day favorable outcome (p = 0.952), and 90-day mortality (p = 0.931) between the sexes. CONCLUSION: Female patients had lower hospitalization costs and sICH rates than males after EVT for AIS. Identifying such differences and implementing measures, including adaptations to workflow optimization, would help to reduce the ONT and last known normal-to-puncture time seen in males to improve patient outcomes. Despite such variations, favorable outcomes and mortality are similar in female and male AIS patients.
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Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Trombectomía , Humanos , Masculino , Femenino , Accidente Cerebrovascular Isquémico/cirugía , Trombectomía/métodos , Procedimientos Endovasculares/métodos , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Factores Sexuales , Resultado del Tratamiento , China , Anciano de 80 o más Años , Caracteres SexualesRESUMEN
Detail preservation is a major challenge for single image super-resolution (SISR). Many deep learning-based SISR methods focus on lightweight network design, but these may fall short in real-world scenarios where performance is prioritized over network size. To address these problems, we propose a novel plug-and-play attention module, rich elastic mixed attention (REMA), for SISR. REMA comprises the rich spatial attention module (RSAM) and the rich channel attention module (RCAM), both built on Rich Structure. Based on the results of our research on the module's structure, size, performance, and compatibility, Rich Structure is proposed to enhance REMA's adaptability to varying input complexities and task requirements. RSAM learns the mutual dependencies of multiple LR-HR pairs and multi-scale features, while RCAM accentuates key features through interactive learning, effectively addressing detail loss. Extensive experiments demonstrate that REMA significantly improves performance and compatibility in SR networks compared to other attention modules. The REMA-based SR network (REMA-SRNet) outperforms comparative algorithms in both visual effects and objective evaluation quality. Additionally, we find that module compatibility correlates with cardinality and in-branch feature bandwidth, and that networks with high effective parameter counts exhibit enhanced robustness across various datasets and scale factors in SISR.
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OBJECTIVE: Medical staff, especially nurses, suffered great anxiety and stress from the COVID-19 pandemic, which negatively affected their sleep quality. In this study, we aimed to analyze the sleep quality of nursing staff after terminating the Zero-COVID-19 policy in China. METHODS: 506 participants were involved in our study. The Pittsburgh Sleep Quality Index (PSQI) was used to evaluate the sleep status of the participants. Binary regression was performed to evaluate the impact factors related to sleep difficulty. RESULTS: The majority of participants (96.44%) suffered from sleep disturbances. There were significant differences in age, education level and front-line activity between participants with good sleep quality and sleep difficulty. Younger age (16-25 years old) was independently associated with less sleep difficulty, while front-line activity was independently associated with severe sleep difficulty. CONCLUSION: Sleep disorder was very common among nurses after ending the Zero-COVID-19 policy in China. More front-line nurses suffered severe sleep difficulty in particular, which should be worthy of attention.
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Nucleophilic substitutions are fundamentally important transformations in synthetic organic chemistry. Despite the substantial advances in bimolecular nucleophilic substitutions (SN2) at saturated carbon centers, analogous SN2 reaction at the amide nitrogen atom remains extremely limited. Here we report an SN2 substitution method at the amide nitrogen atom with amine nucleophiles for nitrogen-nitrogen (N-N) bond formation that leads to a novel strategy toward biologically and medicinally important hydrazide derivatives. We found the use of sulfonate-leaving groups at the amide nitrogen atom played a pivotal role in the reaction. This new N-N coupling reaction allows the use of O-tosyl hydroxamates as electrophiles and readily available amines, including acyclic aliphatic amines and saturated N-heterocycles as nucleophiles. The reaction features mild conditions, broad substrate scope (>80 examples), excellent functional group tolerability, and scalability. The method is applicable to late-stage modification of various approved drug molecules, thus enabling complex hydrazide scaffold synthesis.
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Metal-organic frameworks (MOFs) are proved to be good precursors to derive various nanomaterials with desirable functions, but so far the controllable synthesis of ordered mesoporous derivatives from MOFs has not been achieved. Herein, this work reports, for the first time, the construction of MOF-derived ordered mesoporous (OM) derivatives by developing a facile mesopore-inherited pyrolysis-oxidation strategy. This work demonstrates a particularly elegant example of this strategy, which involves the mesopore-inherited pyrolysis of OM-CeMOF into a OM-CeO2 @C composite, followed by the oxidation removal of its residual carbon, affording the corresponding OM-CeO2 . Furthermore, the good tunability of MOFs helps to allodially introduce zirconium into OM-CeO2 to regulate its acid-base property, thus boosting its catalytic activity for CO2 fixation. Impressively, the optimized Zr-doped OM-CeO2 can achieve above 16 times higher catalytic activity than its solid CeO2 counterpart, representing the first metal oxide-based catalyst to realize the complete cycloaddition of epichlorohydrin with CO2 under ambient temperature and pressure. This study not only develops a new MOF-based platform for enriching the family of ordered mesoporous nanomaterials, but also demonstrates an ambient catalytic system for CO2 fixation.
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3D printing technology has demonstrated great potential in fabricating flexible and customizable high-performance batteries, which are highly desired in the forthcoming intelligent and ubiquitous energy era. However, a significant performance gap, especially in cycling stability, still exists between the 3D-printed and conventional electrodes, seriously limiting the practical applications of 3D-printed batteries. Here, for the first time, a series of thermoplastic polyurethane (TPU)-based 3D-printed electrodes is developed via fused deposition modeling for flexible and customizable high-performance lithium-ion batteries. The TPU-based electrode filaments in kilogram order are prepared via a facile extrusion method. As a result, the electrodes are well-printed with high dimensional accuracy, flexibility, and mechanical stability. Notably, 3D-printed TPU-LFP electrodes exhibit a capacity retention of 100% after 300 cycles at 1C, which is among the best cycling performance of all the reported 3D-printed electrodes. Such excellent performance is associated with the superb stress cushioning properties of the TPU-based electrodes that can accommodate the volume change during the cycling and thus significantly prevent the collapse of 3D-printed electrode structures. The findings not only provide a new avenue to achieve customizable and flexible batteries but also guide a promising way to erase the performance gap between 3D-printed and conventional lithium-ion batteries.
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In this paper, we present the design of a compact reconfigurable polarization beam splitter (PBS) enabled by ultralow-loss phase-changing Sb2Se3. By harnessing the phase-change-mediated mode coupling in a directional coupler (DC), guided light with different polarizations could be routed into different paths and this routing could be dynamically switched upon the phase change of Sb2Se3. With an optimized DC region, the proposed PBS demonstrates efficient polarization splitting with crosstalk less than -21.3â dB and insertion loss less than 0.16â dB at 1550â nm for both phase states of Sb2Se3, and features energy efficient property benefitting from the nonvolatile phase change of Sb2Se3, which holds great potentials for on-chip applications involving polarization control, including polarization-division multiplexing system, quantum photonics, microwave photonics, etc.
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Factors related to mortality after osteoporotic hip fracture (HF) have been investigated intensively, except for proximal femoral bone mineral density (BMD), which is also the primary cause of osteoporosis. In this study, we aimed to investigate the association of hip BMD with mortality risk after HF. Four hundred and eleven elderly patients with HF in Beijing, China, were included and prospectively followed up with a median time of 3 years. At baseline, quantitative CT technique (QCT) was used to measure areal BMD (aBMD) of the unaffected hip. Areal BMDs of the total hip (TH), femoral neck (FN), trochanter (TR), and intertrochanter were analyzed with postoperative mortality as the primary outcome. A total of 394 patients (78.59 ± 7.59 years, 75.4% female) were included in our final analysis, with 86 (82.23 ± 7.00 years, 81.4% female) dead. All hip bone densities demonstrated a significant association with mortality risks in the unadjusted model, but only TR aBMD remained significantly correlated after adjusting for all covariates. Compared to the lower TR aBMD group, the higher TR aBMD group yielded significantly lower death risks (HR 0.21 95% CI 0.05-0.9, P = 0.036). Higher survival probabilities were observed for higher TH and TR aBMD in survival analysis (P < 0.001). Hip BMD, especially TR BMD assessed by QCT, is an independent risk factor for postoperative mortality following HF. QCT may present a promising avenue for opportunistic analysis in immobilized patients, providing valuable information for early detection and personalized interventions to enhance patient outcomes.
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Fracturas de Cadera , Fracturas Osteoporóticas , Humanos , Femenino , Anciano , Masculino , Densidad Ósea , Estudios Prospectivos , Absorciometría de Fotón/métodos , Fracturas de Cadera/etiología , Cuello Femoral , Fracturas Osteoporóticas/complicacionesRESUMEN
OBJECTIVE: To evaluate the clinical effectiveness of orthogeriatric co-management care in long-lived elderly hip fracture patients (age ≥ 90). METHODS: Secondary analysis was conducted in long-lived hip fracture patients between 2018 to 2019 in 6 hospitals in Beijing, China. Patients were divided into the orthogeriatric co-management group (CM group) and traditional consultation mode group (TC group) depending on the management mode. With 30-day mortality as the primary outcome, multivariate regression analyses were performed after adjusting for potential covariates. 30-day mobility and quality of life were compared between groups. RESULTS: A total of 233 patients were included, 223 of whom completed follow-up (125 in CM group, 98 in TC group). The average age was 92.4 ± 2.5 years old (range 90-102). The 30-day mortality in CM group was significantly lower than that in TC group after adjustments for (2.4% vs. 10.2%; OR = 0.231; 95% CI 0.059 ~ 0.896; P = 0.034). The proportion of patients undergoing surgery and surgery performed within 48 h also favored the CM group (97.6% vs. 85.7%, P = 0.002; 74.4% vs. 24.5%, P < 0.001; respectively). In addition, much more patients in CM group could walk with or without aids in postoperative 30 days than in the TC group (87.7% vs. 60.2%, P < 0.05), although differences were not found after 1-year follow-up. And there was no significant difference in total cost between the two groups (P > 0.05). CONCLUSIONS: For long-lived elderly hip fracture patients, orthogeriatric co-management care lowered early mortality, improved early mobility and compared with the traditional consultation mode.
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Fracturas de Cadera , Calidad de Vida , Anciano , Humanos , Anciano de 80 o más Años , Estudios Prospectivos , Fracturas de Cadera/cirugía , China , HospitalesRESUMEN
Lewy pathologies, which mainly consist of insoluble α-synuclein (α-syn) aggregates, are the hallmarks of Parkinson's disease and many other neurodegenerative diseases termed "synucleinopathies". Detection of Lewy pathologies with optical methods is of interest for preclinical studies, while the α-syn fluorescent probe is still in great demand. By rational design, we obtained a series of D-π-A-based trisubstituted alkenes with acceptable optical properties and high binding affinities to α-syn fibrils. Among these probes, FPQXN and TQXN-2 exhibited high binding affinities (6 and 8 nM, respectively), significant fluorescence enhancements (17.2- and 26.6-fold, respectively), and satisfying quantum yields (36.5% and 10.4%, respectively), which met the need for the in vitro neuropathological staining of Lewy pathologies in the PD brain sections. In addition, TQXN-2 showed great potential in fluorescent discrimination of Lewy pathologies and Aß plaques. Our research provides flexible tools for in vitro detection of α-syn aggregates and offers new structural frameworks for the further development of α-syn fluorescent probes.
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Colorantes Fluorescentes , Enfermedad de Parkinson , Humanos , Colorantes Fluorescentes/metabolismo , Alquenos/metabolismo , alfa-Sinucleína/química , Enfermedad de Parkinson/metabolismo , Placa Amiloide/metabolismo , Encéfalo/metabolismoRESUMEN
On-chip nonvolatile photonic switches enabled by phase change materials (PCMs) are promising building blocks for power-efficient programmable photonic integrated circuits. However, large absorption loss in conventional PCMs (such as Ge2Sb2Te5) interacting with weak evanescent waves in silicon waveguides usually leads to high insertion loss and a large device footprint. In this paper, we propose a 2×2 photonic switch based on two-mode interference in a multimode slot waveguide (MSW) with ultralow loss Sb2S3 integrated inside the slot region. The MSW supports two lowest order TE modes, i.e., symmetric TE00 and antisymmetric TE01 modes, and the phase of Sb2S3 could actively tune two-mode interference behavior. Owing to the enhanced electric field in the slot, the interaction strength between modal field and Sb2S3 could be boosted, and a photonic switch containing a â¼9.4 µm-long Sb2S3-MSW hybrid section could effectively alter the light transmission between bar and cross ports upon the phase change of Sb2S3 with a cross talk (CT) less than -13.6 dB and an insertion loss (IL) less than 0.26 dB in the telecommunication C-band. Especially at 1550 nm, the CT in the amorphous (crystalline) Sb2S3 is -36.1 dB (-31.1 dB) with a corresponding IL of 0.073 dB (0.055 dB). The proposed 2×2 photonic switch is compact in size and compatible with on-chip microheaters, which may find promising applications in reconfigurable photonic devices.
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BACKGROUND: The postgraduate entrance examination can be a milestone for many medical students to advance their careers. An increasing number of students are competing for limited postgraduate offers available, and failure to enter postgraduate studies can have adverse mental health consequences. In this paper, we aim to investigate the mental health status of medical students during the postgraduate application entrance examination and to provide a targeted basis for mental health education and psychological counselling. METHODS: Using the Symptom Checklist-90 scale (SCL-90) questionnaire, the mental health status of 613 students who passed two rounds of the Postgraduate Entrance Examination in 2019 to enroll in Guangzhou Medical University in China was evaluated and followed up for retesting 6 months later. We used SPSS 20.0 statistical software for comparative analysis, including One-Sample T-Test, Independent-Samples T-Test, Paired Samples T-Test and Chi-square Test. RESULTS: Our data showed that 12.10% of students had mental health problems during the postgraduate entrance examination, and it decreased significantly to 4.40% at the 6-month follow-up after the examination period finished (P < 0.01). Somatization was the most significant symptom of the students both during and after the postgraduate entrance examination stages. All SCL-90 factors were scored significantly lower both in and after the postgraduate entrance examination stages than the 2008 national college student norm score (P < 0.01). Excluding psychiatric factors, all other SCL-90 factors in the postgraduate entrance examination stage scored higher than the graduate stage (P < 0.05), and the total score of SCL-90 in female medical students was higher compared to male students (P < 0.05). CONCLUSION: The postgraduate entrance examination event has a significant negative influence on students' mental health. The mental health of college and graduate students as an important part of their higher education experience should be systematically studied, and psychological counselling or help should be provided to them throughout their studies, specifically during the examination period. Educating applicants about mental health should be implemented during the postgraduate entrance examination curriculum.
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Estudiantes de Medicina , Humanos , Masculino , Femenino , Estudiantes de Medicina/psicología , Salud Mental , Curriculum , Encuestas y Cuestionarios , Estado de SaludRESUMEN
Reconfigurable silicon photonic devices attract much research attention, and hybrid integration with tunable phase-change materials (PCMs) exhibiting large refractive index contrast between amorphous (Am) and crystalline (Cr) states is a promising way to achieve this goal. Here, we propose and numerically investigate a Sb2Se3-Si hybrid waveguide Bragg filter operating in the telecom C-band on the silicon-on-insulator (SOI) platform. The proposed device consists of a Bragg grating (BG) with a thin top layer of ultralow-loss Sb2Se3 PCM interacting with evanescent field of the silicon waveguide mode. By harnessing the ultralow-loss and reversible index change of Sb2Se3 film, the spectral response of the hybrid BGs could be dynamically tuned. We also theoretically investigate the reversible phase transitions between Am and Cr states of Sb2Se3 film that could be attained by applying voltage pulses on the indium-tin-oxide (ITO) strip heater covered on Sb2Se3 film. Thermal simulations show that a 2 V (4.5 V) pulse with a duration of 400 ns (55 ns) applied to electric contacts would produce crystallization (or amorphization). The proposed structure may find great potential for on-chip phase tunable devices on a silicon platform.
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Augmented and virtual reality (AR, VR) are becoming promising tools in neurosurgery. AR and VR can reduce challenges associated with conventional approaches via the simulation and mimicry of specific environments of choice for surgeons. Awake craniotomy (AC) enables the resection of lesions from eloquent brain areas while monitoring higher cortical and subcortical functions. Evidence suggests that both surgeons and patients benefit from the various applications of AR and VR in AC. This paper investigates the application of AR and VR in AC and assesses its prospective utility in neurosurgery. A systematic review of the literature was performed using PubMed, Scopus, and Web of Science databases in accordance with the PRISMA guidelines. Our search results yielded 220 articles. A total of six articles consisting of 118 patients have been included in this review. VR was used in four papers, and the other two used AR. Tumour was the most common pathology in 108 patients, followed by vascular lesions in eight patients. VR was used for intraoperative mapping of language, vision, and social cognition, while AR was incorporated in preoperative training of white matter dissection and intraoperative visualisation and navigation. Overall, patients and surgeons were satisfied with the applications of AR and VR in their cases. AR and VR can be safely incorporated during AC to supplement, augment, or even replace conventional approaches in neurosurgery. Future investigations are required to assess the feasibility of AR and VR in various phases of AC.
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Realidad Aumentada , Realidad Virtual , Humanos , Vigilia , Craneotomía , Procedimientos Neuroquirúrgicos/métodosRESUMEN
INTRODUCTION: The aim of this study was to investigate for possible associations between an early increase in body temperature within 24 hours of endovascular therapy (EVT) for large vessel occlusion stroke and the presence of symptomatic intracranial hemorrhage (sICH) and other clinical outcomes. METHODS: This was a retrospective study of consecutive patients with large vessel occlusion stroke who were treated with EVT from August 2018 to June 2021. Patients were divided into two groups based on the presence of fever, as defined by a Peak Body Temperature (PBT) of ≥37.3 °C. The presence of sICH and other clinical outcomes were compared between the two groups. RESULTS: The median NIHSS admission score (IQR) was 16.0 (12.0, 21.0), with higher NIHSS scores in the PBT ≥37.3 °C group than in the PBT <37.3 °C group (18 vs 14, respectively; p = 0.002). There were no differences in clinical outcomes at 3 months between patients with PBT <37.3 °C and patients with PBT between 37.3 °C and 38 °C. However, patients with PBT ≥38 °C had an increased risk of sICH (adjusted odds ratio (OR) = 8.8, 95% confidence interval (95% CI): 1.7-46.0; p = 0.01), increased inpatient death or hospice discharge (OR = 10.5, 95% CI: 2.0-53.9; p = 0.005), poorer clinical outcome (OR = 25.6, 95% CI: 5.2-126.8; p < 0.001), and increased 3-month mortality (OR = 6.6, 95% CI: 1.8-24.6; p = 0.01). CONCLUSIONS: Elevated PBT (≥38 °C) within 24 hours of EVT was significantly associated with an increased incidence of symptomatic intracranial hemorrhage, discharge to hospice or inpatient death, poorer clinical outcome and 3-month mortality, and with less functional independence. Further large-scale, prospective and multicenter trials are needed to confirm these findings.