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1.
Methods Mol Biol ; 2597: 25-38, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36374412

RESUMO

Binding of chemokines to glycosaminoglycans (GAGs) is classically described as initiating inflammatory cell migration and creating tissue chemokine gradients that direct immune cell responses initiating local leukocyte chemotaxis into damaged or transplanted tissues. The interaction between chemokines and GAGs is an important factor affecting transplant rejection, and blocking the interactions between chemokines and GAGs can significantly reduce acute rejection after transplantation. Here, we investigated the interaction between chemokines and GAGs by establishing a mouse model of acute rejection after kidney transplantation.


Assuntos
Transplante de Rim , Camundongos , Animais , Humanos , Transplante de Rim/efeitos adversos , Quimiocinas/metabolismo , Doadores de Tecidos , Rejeição de Enxerto , Glicosaminoglicanos/metabolismo , Aloenxertos
2.
Neural Regen Res ; 18(2): 350-356, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35900429

RESUMO

Sirtuin 2 (SIRT2) inhibition or Sirt2 knockout in animal models protects against the development of neurodegenerative diseases and cerebral ischemia. However, the role of SIRT2 in traumatic brain injury (TBI) remains unclear. In this study, we found that knockout of Sirt2 in a mouse model of TBI reduced brain edema, attenuated disruption of the blood-brain barrier, decreased expression of the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome, reduced the activity of the effector caspase-1, reduced neuroinflammation and neuronal pyroptosis, and improved neurological function. Knockout of Sirt2 in a mechanical stretch injury cell model in vitro also decreased expression of the NLRP3 inflammasome and pyroptosis. Our findings suggest that knockout of Sirt2 is neuroprotective against TBI; therefore, Sirt2 could be a novel target for TBI treatment.

3.
Quant Imaging Med Surg ; 12(4): 2378-2384, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35371957

RESUMO

Background: To investigate the value of intraoperative frozen section examination (IFSE) in multiparametric magnetic resonance imaging/transrectal ultrasound (mpMRI/TRUS) fusion prostate biopsy in a major pandemic. Methods: A total of 35 patients were prospectively enrolled in our hospital from March 2020 to January 2021. The mpMRI/TRUS fusion system was used to perform a targeted biopsy, and the collected specimens were examined by IFSE (Observation Group 1). Then, a targeted biopsy was performed again for routine pathological examination (Observation Group 2). Finally, a systemic biopsy was performed, and the obtained specimens were routinely examined (Control Group). The positive rate, single core positive rate, Gleason score, and time to obtain pathological reports were compared between the groups. Results: The positive rate was 48.6% (17/35) in the control group, 48.6% (17/35) in Observation Group 1, and 51.4% (18/35) in Observation Group 2, showing no significant difference (P>0.05). The single core positive rates were 17.8%, 44.6%, and 47.1% in the Control Group, Observation Group 1, and Observation Group 2, respectively. Observation Group 1 and Observation Group 2 were significantly different from the Control Group (P<0.001). No participants in Observation Group 1 had increased or decreased Gleason scores compared with those in Observation Group 2. The time to obtain the pathological report was 0.025±0.014 days and 4.216±1.073 days for Observation Group 1 and Observation Group 2, respectively, showing a significant difference (P<0.001). Conclusions: This study showed that IFSE can not only rapidly obtain the pathological report of an mpMRI/TRUS biopsy, but can also ensure the accuracy of the pathological diagnosis. Trial Registration: CHICTR, Identifier: ChiCTR2000040789. Registered 10 December 2020 - Retrospectively registered, http://www.chictr.org.cn/edit.aspx?pid=63252&htm=4.

4.
Transl Cancer Res ; 11(10): 3724-3740, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36388031

RESUMO

Background: Colon cancer (CC) is one of the most common cancers with high morbidity globally. Ubiquitination is involved in the characterization of multiple biological processes, and some ubiquitinated enzymes are associated with the prognosis of CC. However, the prognostic model associated with ubiquitination-related genes (URGs) for CC is unavailable. Methods: Gene expression data, somatic mutations, transcriptome profiles, microsatellite instability status (MSI) status, and clinical information for CC were obtained from The Cancer Genome Atlas (TCGA) dataset. Seven URGs were used for establishing a prognostic prediction model, which was constructed and validated in GSE17538. Besides, genomic variance analysis (GSVA) was used to explore further the differences in biological pathway activation status between the high-risk and low-risk groups. Finally, the single-sample gene set enrichment analysis (ssGSEA) and ESTIMATE algorithm analysis were used to characterize the cellular infiltration in the microenvironment. Results: A seven-URG prognostic signature was established, based on which patients in the training and test groups could be divided into high-risk and low-risk groups. The results demonstrated that the model has a solid ability to predict the prognosis of CC patients. Conclusions: We established a prognostic prediction model for CC based on ubiquitination. Then we analyzed the genetic characteristics associated with ubiquitination and the tumor microenvironment (TME) cell infiltration in CC. These results are worthy of exploring new clinical treatment strategies for CC.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36401592

RESUMO

A non-aromatic expanded carbaporphyrinoid, incorporating two built-in 2,7-pyrenylene moieties was synthesized. The intrinsically labile topographic structure was demonstrated by proton-triggered conformational changes between the figure-of-eight and quasi-Möbius conformers. Upon treatment with Pd(OAc) 2 , the reaction produces two bis-Pd II complexes with distinct coordination modes. Metal coordination serves to fix the oligopyrrolic macrocyclic frame-works with the net result that both bis-Pd II complexes could be resolved by chiral high-performance liquid chromatography (HPLC). The isolated enantiomers showed considerable configurational stability and persistent chiroptical properties as evidenced by the intense response in the circular dichroism (CD) spectra from 300-850 nm and the record high absorption dissymmetry factors ( g abs of up to 0.038) seen in the near-infrared spectral region. In addition, the mutual interconversion of the enantiomers was found to be stereospecific and to favor the more stable isomers in the presence of the weakly acidic solvent deuterated chloroform.

6.
Front Med (Lausanne) ; 9: 1001801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405610

RESUMO

Background: Factors that may influence the recovery of patients with confirmed SARS-CoV-2 infection hospitalized in the Fangcang shelter were explored, and machine learning models were constructed to predict the duration of recovery during the Omicron BA. 2.2 pandemic. Methods: A retrospective study was conducted at Hongqiao National Exhibition and Convention Center Fangcang shelter (Shanghai, China) from April 9, 2022 to April 25, 2022. The demographics, clinical data, inoculation history, and recovery information of the 13,162 enrolled participants were collected. A multivariable logistic regression model was used to identify independent factors associated with 7-day recovery and 14-day recovery. Machine learning algorithms (DT, SVM, RF, DT/AdaBoost, AdaBoost, SMOTEENN/DT, SMOTEENN/SVM, SMOTEENN/RF, SMOTEENN+DT/AdaBoost, and SMOTEENN/AdaBoost) were used to build models for predicting 7-day and 14-day recovery. Results: Of the 13,162 patients in the study, the median duration of recovery was 8 days (interquartile range IQR, 6-10 d), 41.31% recovered within 7 days, and 94.83% recovered within 14 days. Univariate analysis showed that the administrative region, age, cough medicine, comorbidities, diabetes, coronary artery disease (CAD), hypertension, number of comorbidities, CT value of the ORF gene, CT value of the N gene, ratio of ORF/IC, and ratio of N/IC were associated with a duration of recovery within 7 days. Age, gender, vaccination dose, cough medicine, comorbidities, diabetes, CAD, hypertension, number of comorbidities, CT value of the ORF gene, CT value of the N gene, ratio of ORF/IC, and ratio of N/IC were related to a duration of recovery within 14 days. In the multivariable analysis, the receipt of two doses of the vaccination vs. unvaccinated (OR = 1.118, 95% CI = 1.003-1.248; p = 0.045), receipt of three doses of the vaccination vs. unvaccinated (OR = 1.114, 95% CI = 1.004-1.236; p = 0.043), diabetes (OR = 0.383, 95% CI = 0.194-0.749; p = 0.005), CAD (OR = 0.107, 95% CI = 0.016-0.421; p = 0.005), hypertension (OR = 0.371, 95% CI = 0.202-0.674; p = 0.001), and ratio of N/IC (OR = 3.686, 95% CI = 2.939-4.629; p < 0.001) were significantly and independently associated with a duration of recovery within 7 days. Gender (OR = 0.736, 95% CI = 0.63-0.861; p < 0.001), age (30-70) (OR = 0.738, 95% CI = 0.594-0.911; p < 0.001), age (>70) (OR = 0.38, 95% CI = 0292-0.494; p < 0.001), receipt of three doses of the vaccination vs. unvaccinated (OR = 1.391, 95% CI = 1.12-1.719; p = 0.0033), cough medicine (OR = 1.509, 95% CI = 1.075-2.19; p = 0.023), and symptoms (OR = 1.619, 95% CI = 1.306-2.028; p < 0.001) were significantly and independently associated with a duration of recovery within 14 days. The SMOTEEN/RF algorithm performed best, with an accuracy of 90.32%, sensitivity of 92.22%, specificity of 88.31%, F1 score of 90.71%, and AUC of 89.75% for the 7-day recovery prediction; and an accuracy of 93.81%, sensitivity of 93.40%, specificity of 93.81%, F1 score of 93.42%, and AUC of 93.53% for the 14-day recovery prediction. Conclusion: Age and vaccination dose were factors robustly associated with accelerated recovery both on day 7 and day 14 from the onset of disease during the Omicron BA. 2.2 wave. The results suggest that the SMOTEEN/RF-based model could be used to predict the probability of 7-day and 14-day recovery from the Omicron variant of SARS-CoV-2 infection for COVID-19 prevention and control policy in other regions or countries. This may also help to generate external validation for the model.

7.
Front Surg ; 9: 1002744, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406351

RESUMO

Objective: To assess the mid-long-term clinical and radiological outcomes of zero-profile (ZP) compared with stand-alone (ST) cages for two-level anterior cervical discectomy and fusion (ACDF). Methods: We included 77 patients (39 women and 38 men) who underwent two-level ACDF between May 5, 2016, and May 5, 2020, and who were followed up for at least 1 year. The subjects were divided into the ST (n = 38) and ZP (n = 39) group. For the evaluation of functional status, Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analogue Scale (VAS) scores were used. Additionally, radiological outcomes and procedure complications were observed at final follow-up. Results: Both groups had excellent clinical outcomes at the final follow-up. There were no significant intergroup (ZP vs. ST) differences in the fusion rate (91.02% vs. 90.79%, P > 0.05) and postoperative dysphagia (15.4% vs. 2.6%, P = 0.108). However, the disc height at the final follow-up in the ZP group was higher than that in the ST group (6.86 ± 0.84 vs. 6.17 ± 1.03, P = 0.002). The ZP group accomplished a lower loss of cervical lordosis (18.46 ± 4.78 vs. 16.55 ± 4.36, P = 0.071), but without reaching statistical significance. Conclusion: ACDF with either ZP or ST cages turns out to be a dependable strategy for two-level ACDF in terms of clinical results. However, compared with the ST, the ZP cage may achieve a significantly lower loss of disc height.

8.
Front Pharmacol ; 13: 1008755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408251

RESUMO

Gastric cancer is an extremely burdensome and challenging malignant tumor with a high incidence and a high mortality rate, which seriously results in a thorny prognosis for oncology patients. Surgical treatment combined with postoperative adjuvant therapy are currently the most regular methods for the treatment of locally advanced gastric cancer (LAGC), but long-term efficacy is not an ideal outcome. Therefore, herein we report a case of a pathologically confirmed complete remission of LAGC treated by the administration of neoadjuvant therapy combined with fluorescence laparoscopic surgery with more significant long-term survival. With that being mentioned, a 60-year-old man was diagnosed as moderately differentiated gastric antrum adenocarcinoma (T3N1M0). Moreover, after three cycles of SOXAP regimen (Oxaliplatin + S-1+Apatinib + Camrelizumab), and it was found out that the gastric lesion was smaller in size than before, total laparoscopic radical resection of the distal gastric cancer was performed at the time. Furthermore, no tumor cells were seen in gross specimen post operatively, achieving complete remission of the case. In addition, he also underwent three cycles of SOXAP regimen postoperatively. Interestingly and assuredly, he was in good health after an almost 2-year follow up period. These results suggest that this therapeutic regimen is a promising treatment modality for the management of locally advanced gastric cancers.

9.
Medicine (Baltimore) ; 101(45): e31744, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36397326

RESUMO

RATIONALE: Adenoid cystic carcinoma (ACC) often occurs in the major and minor salivary glands and other sites containing secretory glands, while ACC of the Bartholin's gland (BG-ACC) in the vulva is rare and easily misdiagnosed. PATIENT CONCERNS: A 58-year-old female was referred to our hospital for further valuation of a mass occurring on the left side of her vulva. In the other hospital, the beginning of the period, local ultrasound showed a vulva mass, which was suspected to be a Bartholin's gland cyst. Mixed neoplasms were considered in some biopsies. When transferred to our hospital, virtuous tumors were considered by ultrasound and magnetic resonance imaging. Pathology initially considered benign hyperplastic active tumor or borderline tumor. DIAGNOSES: Histological, immunochemical, and molecular tests confirmed a diagnosis of BG-ACC, negative surgical margin, without lymphatic metastasis. INTERVENTIONS: Extended excision of the mass at left labia majora plus left inguinal lymph node dissection was performed. OUTCOMES: The patient received surgery therapy, no recurrence was observed during a 18-month follow-up period. LESSONS: Due to its lack of specific characteristics in clinical, ultrasound and imaging, it is easy to be misdiagnosed, Due to its rarity and nonspecific clinical, radiologic and ultrasonographic manifestations, BG-ACC can be easily misdiagnosed. And its pathomorphological features overlap with other benign and malignant tumors occurring at vulva, BG-ACC can be easily misdiagnosed, and diagnosis by puncture biopsy is extremely difficult. Use of paraffin sections to identify tumor growth characteristics, combined with immunohistochemical findings, is the key to the diagnosis of ACC. In rare sites, MYB gene split are helpful in making a definite diagnosis.


Assuntos
Glândulas Vestibulares Maiores , Carcinoma Adenoide Cístico , Neoplasias Vulvares , Humanos , Feminino , Pessoa de Meia-Idade , Glândulas Vestibulares Maiores/patologia , Carcinoma Adenoide Cístico/diagnóstico , Carcinoma Adenoide Cístico/cirurgia , Carcinoma Adenoide Cístico/patologia , Neoplasias Vulvares/diagnóstico , Neoplasias Vulvares/cirurgia , Neoplasias Vulvares/patologia , Vulva/patologia , Erros de Diagnóstico
10.
Int J Biol Macromol ; 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36403774

RESUMO

Protein corona formation can lead to obstructive screening of targeting groups of nanoparticles (NPs). Also, the targeting groups are subjected to physiochemical interactions when exposed to solvents. Here, these two factors can influence NP targeting efficiency. Therefore, it is necessary to prepare a general method of preparing an anti-fouling NPs with protected targeting groups. Here, we designed α-amylase-starch double-layer coated poly (methyl methacrylate-co-acrylic acid) NPs (α-ams-SCMMA NPs), functionalized with aptamer targeting groups and doped with Tetrakis(para-hydraoxylphenyl) porphyrin (TPPOH) as a payload drug. Natural polysaccharide starch and enzyme α-amylase were applied here for thermo-sensitive activation of starch hydrolyzation in order to render the NPs' self-polishing from protein corona effects. During incubation with serum media, the protein corona was formed at the exterior shell of NPs, while the self-polishing process was activated to remove the "protein fouling" when the incubation temperature increased to 37 °C (body temperature). Mechanistically, the starch layer of α-ams-SCMMA NPs was readily hydrolysed by α-amylase, whereby the adsorbed protein corona could be efficiently eliminated and the targeting groups were then presented. With this unique self-polishing NP design, we believe our method can be applied for potential NP applications in cancer therepy due to excellent antifouling property and protected targeting groups.

11.
Plant Mol Biol ; 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414883

RESUMO

Zinc (Zn) deficiency, caused by inadequate Zn intake in the human diet, has serious health implications. Rice (Oryza sativa) is the staple food in regions with a high incidence of Zn deficiency, so raising Zn levels in rice grain could help alleviate Zn deficiency. The wild relatives of cultivated rice vary widely in grain Zn content and thus are suitable resources for improving this trait. However, few loci underlying grain Zn content have been identified in wild rice relatives. Here, we identified a major quantitative trait locus for grain Zn content, Grain Zn Content 1 (qGZnC1), from Yuanjiang common wild rice (Oryza rufipogon Griff.) using map-based cloning. Down-regulating GZnC1 expression reduced the grain Zn content, whereas the presence of GZnC1 had the opposite effect, indicating that GZnC1 is involved in grain Zn content in rice. Notably, GZnC1 is identical to a previously reported gene, EMBRYO SAC ABORTION 1 (ESA1), involved in seed setting rate. The mutation in GZnC1/ESA1 at position 1819 (T1819C) causes delayed termination of protein translation. In addition, GZnC1 is specifically expressed in developing panicles. Several genes related to Zn-transporter genes were up-regulated in the presence of GZnC1. Our results suggest that GZnC1 activates Zn transporters to promote Zn distribution in panicles. Our work thus sheds light on the genetic mechanism of Zn accumulation in rice grain and provides a new genetic resource for improving Zn content in rice.

12.
Colloids Surf B Biointerfaces ; 221: 113007, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36356401

RESUMO

Robust protein-nanomaterial surface analysis is important, but also a challenge. Thrombin plays an important role in the coagulant activity of protein corona mediated by Ca2+ ion exchanged zeolites. However, the mechanism for this modulation remains unresolved. In this study, we proposed a combined computational and experimental approach to determine the adsorbed sites and orientations of thrombin binding to Ca2+ -exchanged LTA-type (CaA) zeolite. Specifically, fourteen ensembles of simulated annealing molecular dynamics (SAMD) simulations and experimental surface residues microenvironment analysis were used to reduce the starting orientations needed for further molecular dynamics (MD) simulations. The combined MD simulations and procoagulant activity characterization also reveal the consequent corresponding deactivation of thrombin on CaA zeolite. It is mainly caused by two aspects: (1) the secondary structure of thrombin can change after its adsorption on the CaA zeolite. (2) The positively charged area of thrombin mediates the preferential interaction between thrombin and CaA zeolite. Some thrombin substrate sites are thus blocked by zeolite after its adsorption. This study not only provides a promising method for characterizing the protein-nanoparticle interaction, but also gives an insight into the design and application of zeolite with high procoagulant activity.

13.
HLA ; 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36373504

RESUMO

The impact of preformed and de novo HLA-DP antibodies after renal transplantation remains controversial and unclear. To address the clinical relevance of HLA-DP antibodies on the outcomes in renal transplantation, we performed a random effect model meta-analysis through a systematic review from inception to December 31, 2021. The outcome was graft loss or acute rejection. Finally five articles were identified as our inclusion criteria. The study which reported 1166 patients included in the final meta-analysis of de novo HLA-DP antibodies after transplantation showed an increased risk of graft loss or acute rejection (OR = 3.6, 95% CI = 1.6-8.10, P = 0.002, I2  = 52%). In the subgroup study, we established that patients with HLA-DP DSA after renal transplantation had a 8.85-fold increased risk of graft loss or acute rejection compared with patients without HLA-DP DSA (p = 0.003).While as for HLA-DP NDSA after renal transplantation, 2.73-fold increased risk of graft loss or acute rejection compared with patients without HLA-DP antibodies (p = 0.04). Besides, the studies which reported 487 patients included in the final meta-analysis of preformed HLA-DP antibodies did not show an increased risk of graft loss or acute rejection (OR = 4.55, 95% CI = 0.79-26.16, P = 0.09, I2  = 57%). The results of our meta-analysis suggested that de novo HLA-DP antibodies especially de novo HLA-DP DSA had a significant deleterious impact on the renal transplant risk of graft loss or acute rejection, while preformed HLA-DP antibodies had a no significant deleterious impact on the risk. The routine detection of HLA-DP antibodies after renal transplantation seems to be very important and may be as one of noninvasive biomarker-guided risk stratification.

14.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(11): 1207-1212, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36398545

RESUMO

OBJECTIVES: To investigate the efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection in the treatment of retinopathy of prematurity (ROP) and the risk factors for recurrence. METHODS: A retrospective analysis was performed on the medical data of 159 infants with ROP who were born in the First Affiliated Hospital of Zhengzhou University and underwent anti-VEGF treatment from January 2016 to December 2021. According to the presence or absence of recurrence within the follow-up period after initial anti-VEGF treatment, they were divided into a recurrence group with 24 infants and a non-recurrence group with 135 infants. The medical data were compared between the two groups, and a multivariate logistic regression analysis was used to investigate the risk factors for the recurrence of ROP after anti-VEGF treatment. RESULTS: After one-time anti-VEGF treatment, all 159 infants showed regression of plus disease. Recurrence was observed in 24 infants (15.1%) after anti-VEGF treatment, with a mean interval of (8.4±2.6) weeks from treatment to recurrence. The multivariate logistic regression analysis showed that preoperative fundus hemorrhage and prolonged total oxygen supply time were risk factors for the recurrence of ROP (P<0.05), while gestational hypertension was a protective factor (P<0.05). CONCLUSIONS: Intravitreal anti-VEGF injection is effective for ROP. Preoperative fundus hemorrhage and long duration of oxygen therapy may increase the risk of ROP recurrence, and further studies are needed to investigate the influence of gestational hypertension on the recurrence of ROP.


Assuntos
Hipertensão Induzida pela Gravidez , Retinopatia da Prematuridade , Lactente , Recém-Nascido , Feminino , Gravidez , Humanos , Retinopatia da Prematuridade/tratamento farmacológico , Fatores de Crescimento Endotelial/uso terapêutico , Estudos Retrospectivos , Inibidores da Angiogênese/efeitos adversos , Fator A de Crescimento do Endotélio Vascular , Fatores de Risco , Hemorragia , Oxigênio/uso terapêutico
15.
Nat Commun ; 13(1): 7091, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402759

RESUMO

Fast-charging is considered as one of the most desired features needed for lithium-ion batteries to accelerate the mainstream adoption of electric vehicles. However, current battery charging protocols mainly consist of conservative rate steps to avoid potential hazardous lithium plating and its associated parasitic reactions. A highly sensitive onboard detection method could enable battery fast-charging without reaching the lithium plating regime. Here, we demonstrate a novel differential pressure sensing method to precisely detect the lithium plating event. By measuring the real-time change of cell pressure per unit of charge (dP/dQ) and comparing it with the threshold defined by the maximum of dP/dQ during lithium-ion intercalation into the negative electrode, the onset of lithium plating before its extensive growth can be detected with high precision. In addition, we show that by integrating this differential pressure sensing into the battery management system (BMS), a dynamic self-regulated charging protocol can be realized to effectively extinguish the lithium plating triggered by low temperature (0 °C) while the conventional static charging protocol leads to catastrophic lithium plating at the same condition. We propose that differential pressure sensing could serve as an early nondestructive diagnosis method to guide the development of fast-charging battery technologies.

16.
Nanomaterials (Basel) ; 12(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36364543

RESUMO

The multilevel properties of a memristor are significant for applications in non-volatile multi-state storage and electronic synapses. However, the reproducibility and stability of the intermediate resistance states are still challenging. A stacked HfOx/ZnO bilayer embedded with copper nanoparticles was thus proposed to investigate its multilevel properties and to emulate synaptic plasticity. The proposed memristor operated at the microampere level, which was ascribed to the barrier at the HfOx/ZnO interface suppressing the operational current. Compared with the stacked HfOx/ZnO bilayer without nanoparticles, the proposed memristor had a larger ON/OFF resistance ratio (~330), smaller operational voltages (absolute value < 3.5 V) and improved cycle-to-cycle reproducibility. The proposed memristor also exhibited four reproducible non-volatile resistance states, which were stable and well retained for at least ~1 year at 85 °C (or ~10 years at 70 °C), while for the HfOx/ZnO bilayer without copper nanoparticles, the minimum retention time of its multiple resistance states was ~9 days at 85 °C (or ~67 days at 70 °C). Additionally, the proposed memristor was capable of implementing short-term and long-term synaptic plasticities.

17.
Sensors (Basel) ; 22(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36365952

RESUMO

In this paper, we propose a novel design, called MixNN, for protecting deep learning model structure and parameters since the model consists of several layers and each layer contains its own structure and parameters. The layers in a deep learning model of MixNN are fully decentralized. It hides communication address, layer parameters and operations, and forward as well as backward message flows among non-adjacent layers using the ideas from mix networks. MixNN has the following advantages: (i) an adversary cannot fully control all layers of a model, including the structure and parameters; (ii) even some layers may collude but they cannot tamper with other honest layers; (iii) model privacy is preserved in the training phase. We provide detailed descriptions for deployment. In one classification experiment, we compared a neural network deployed in a virtual machine with the same one using the MixNN design on the AWS EC2. The result shows that our MixNN retains less than 0.001 difference in terms of classification accuracy, while the whole running time of MixNN is about 7.5 times slower than the one running on a single virtual machine.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Privacidade
18.
Sensors (Basel) ; 22(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36366134

RESUMO

Detecting and locating victims in emergency scenarios comprise one of the most powerful tools to save lives. Fast actions are crucial for victims because time is running against them. Radio devices are currently omnipresent within the physical proximity of most people and allow locating buried victims in catastrophic scenarios. In this work, we present the benefits of using WiFi Fine Time Measurement (FTM), Ultra-Wide Band (UWB), and fusion technologies to locate victims under rubble. Integrating WiFi FTM and UWB in a drone may cover vast areas in a short time. Moreover, the detection capacity of WiFi and UWB for finding individuals is also compared. These findings are then used to propose a method for detecting and locating victims in disaster scenarios.


Assuntos
Desastres , Emergências , Humanos
19.
Natl Sci Rev ; 9(10): nwab226, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36380857

RESUMO

Atomic Fermi gases provide an ideal platform for studying pairing and superfluid physics, using a Feshbach resonance between closed-channel molecular states and open-channel scattering states. Of particular interest is the strongly interacting regime. We show that the closed-channel fraction [Formula: see text] provides an effective probe for important many-body interacting effects, especially through its density dependence, which is absent from two-body theoretical predictions. Here we measure [Formula: see text] as a function of interaction strength and the Fermi temperature [Formula: see text] in a trapped 6Li superfluid throughout the entire Bardeen-Cooper-Schrieffer-Bose-Einstein-condensate crossover, in quantitative agreement with theory when important thermal contributions outside the superfluid core are taken into account. Away from the deep-BEC regime, the fraction [Formula: see text] is sensitive to [Formula: see text]. In particular, our data show [Formula: see text] with [Formula: see text] at unitarity, in quantitative agreement with calculations of a two-channel pairing fluctuation theory, and [Formula: see text] increases rapidly into the BCS regime, reflecting many-body interaction effects as predicted.

20.
Nature ; 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379225

RESUMO

The open circuit voltage (VOC) deficit in perovskite solar cells (PSCs) is greater in wide bandgap (>1.7 eV) cells than in ~1.5 eV perovskites.1,2 Quasi-Fermi level splitting (QFLS) measurements reveal VOC-limiting recombination at the electron transport layer (ETL) contact.3-5 This, we find, stems from inhomogeneous surface potential and poor perovskite-ETL energetic alignment. Common monoammonium surface treatments fail to address this; instead we introduce diammonium molecules to modify the perovskite surface states and achieve a more uniform spatial distribution of surface potential. Using 1,3-propane diammonium (PDA), QFLS increases by 90 meV, enabling 1.79 eV PSCs with a certified 1.33 V VOC, and > 19% power conversion efficiency (PCE). Incorporating this layer into a monolithic all-perovskite tandem, we report a record VOC of 2.19 V (89% of the detailed balance VOC limit) and > 27% PCE (26.3% certified quasi-steady-state). These tandems retain more than 86% of their initial PCE after 500 hrs operation.

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