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1.
IEEE Trans Image Process ; 33: 4363-4376, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39074017

RESUMEN

Data-free knowledge distillation aims to learn a small student network from a large pre-trained teacher network without the aid of original training data. Recent works propose to gather alternative data from the Internet for training student network. In a more realistic scenario, the data on the Internet contains two types of label noise, namely: 1) closed-set label noise, where some examples belong to the known categories but are mislabeled; and 2) open-set label noise, where the true labels of some mislabeled examples are outside the known categories. However, the latter is largely ignored by existing works, leading to limited student network performance. Therefore, this paper proposes a novel data-free knowledge distillation paradigm by utilizing a webly-collected dataset under universal label noise, which means both closed-set and open-set label noise should be tackled. Specifically, we first split the collected noisy dataset into clean set, closed noisy set, and open noisy set based on the prediction uncertainty of various data types. For the closed-set noisy examples, their labels are refined by teacher network. Meanwhile, a noise-robust hybrid contrastive learning is performed on the clean set and refined closed noisy set to encourage student network to learn the categorical and instance knowledge inherited by teacher network. For the open-set noisy examples unexplored by previous work, we regard them as unlabeled and conduct self-supervised learning on them to enrich the supervision signal for student network. Intensive experimental results on image classification tasks demonstrate that our approach can achieve superior performance to state-of-the-art data-free knowledge distillation methods.

2.
Chinese Journal of Biotechnology ; (12): 695-712, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-970401

RESUMEN

Phytoremediation plays an important role in the treatment of heavy metal pollution in soil. In order to elucidate the mechanism of salicylic acid (SA) on copper absorption, seedlings from Xuzhou (with strong Cu-tolerance) and Weifang Helianthus tuberosus cultivars (with weak Cu-tolerance) were selected for pot culture experiments. 1 mmol/L SA was sprayed upon 300 mg/kg soil copper stress, and the photosynthesis, leaf antioxidant system, several essential mineral nutrients and the changes of root upon copper stress were analyzed to explore the mechanism of copper resistance. The results showed that Pn, Tr, Gs and Ci upon copper stress decreased significantly compared to the control group. Meanwhile, chlorophyll a, chlorophyll b and carotenoid decreased with significant increase in initial fluorescence (F0), maximum photochemical quantum yield of PSⅡ (Fv/Fm), electron transfer rate (ETR) and photochemical quenching coefficient (qP) content all decreased. The ascorbic acid (AsA) content was decreased, the glutathione (GSH) value was increased, the superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in the leaves were decreased, and the peroxidase (POD) activity was significantly increased. SA increased the Cu content in the ground and root system, and weakened the nutrient uptake capacity of K, Ca, Mg, and Zn in the root stem and leaves. Spray of exogenous SA can maintain the opening of leaf stomata, improve the adverse effect of copper on photosynthetic pigment and PSⅡ reaction center. Mediating the SOD and APX activity started the AsA-GSH cycle process, effectively regulated the antioxidant enzyme system in chrysanthemum taro, significantly reduced the copper content of all parts of the plant, and improved the ion exchange capacity in the body. External SA increased the content of the negative electric group on the root by changing the proportion of components in the root, promoted the absorption of mineral nutrient elements and the accumulation of osmoregulatory substances, strengthened the fixation effect of the root on metal copper, and avoided its massive accumulation in the H. tuberosus body, so as to alleviate the inhibitory effect of copper on plant growth. The study revealed the physiological regulation of SA upon copper stress, and provided a theoretical basis for planting H. tuberosus to repair soil copper pollution.


Asunto(s)
Antioxidantes , Cobre , Helianthus/metabolismo , Ácido Salicílico/farmacología , Clorofila A/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Clorofila/farmacología , Ácido Ascórbico , Superóxido Dismutasa/metabolismo , Fotosíntesis , Glutatión , Hojas de la Planta , Estrés Fisiológico , Plantones
3.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-22276865

RESUMEN

Background and ObjectivesCOVID-19 vaccine was first recommended for children ages 5-11 years on November 2, 2021. This report describes COVID-19 vaccination coverage and parental intent to vaccinate their child ages 5-11 years, overall, by sociodemographic characteristics, and by social and behavioral drivers of vaccination, the fourth month after recommendation. MethodsWe analyzed data from 5,438 interviews conducted in February 2022 from the National Immunization Survey-Child COVID Module (NIS-CCM), a national random-digit-dial cellular telephone survey of households with children. Results30.9% of children ages 5-11 were vaccinated with [≥]1 dose of COVID-19 vaccine, 35.2% were unvaccinated and the parent reported they probably or definitely would get the child vaccinated or were unsure, and 33.9% were unvaccinated and the parent probably or definitely would not get the child vaccinated. Vaccination coverage and parental intent differed by sociodemographic variables, including income, health insurance status, and rurality. Parental intent to vaccinate children also differed by ethnicity and race. Concern about the child getting COVID-19 and confidence in vaccine importance and safety were positively associated with vaccination receipt and intent to get the child vaccinated. ConclusionsBy the fourth month of the COVID-19 vaccination program for children ages 5-11 years, less than one-third were vaccinated, and coverage was lower for some sociodemographic subgroups. An additional one-third of children had a parent who was open to vaccinating the child. Efforts to address parental concerns regarding vaccine safety and to convey the importance of the vaccine might improve vaccination coverage.

4.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-22271847

RESUMEN

IntroductionEmployer vaccination requirements have been used to increase vaccination uptake among healthcare personnel (HCP). In summer 2021, HCP were the group most likely to have employer requirements for COVID-19 vaccinations as healthcare facilities led the implementation of such requirements. This study examined the association between employer requirements and HCPs COVID-19 vaccination status and attitudes about the vaccine. MethodsParticipants were a national representative sample of United States (US) adults who completed the National Immunization Survey Adult COVID Module (NIS-ACM) during August-September 2021. Respondents were asked about COVID-19 vaccination and intent, requirements for vaccination, place of work, attitudes surrounding vaccinations, and sociodemographic variables. This analysis focused on HCP respondents. We first calculated the weighted proportion reporting COVID-19 vaccination for HCP by sociodemographic variables. Then we computed unadjusted and adjusted prevalence ratios for vaccination coverage and key indicators on vaccine attitudes, comparing HCP based on individual self-report of vaccination requirements. ResultsOf 12,875 HCP respondents, 41.5% reported COVID-19 vaccination employer requirements. Among HCP with vaccination requirements, 90.5% had been vaccinated against COVID-19, as compared to 73.3% of HCP without vaccination requirements--a pattern consistent across sociodemographic groups. Notably, the greatest differences in uptake between HCP with and without employee requirements were seen in sociodemographic subgroups with the lowest vaccination uptake, e.g., HCP aged 18-29 years, HCP with high school or less education, HCP living below poverty, and uninsured HCP. In every sociodemographic subgroup examined, vaccine uptake was more equitable among HCP with vaccination requirements than in HCP without. Finally, HCP with vaccination requirements were also more likely to express confidence in the vaccines safety (68.3% vs. 60.1%) and importance (89.6% vs 79.6%). ConclusionIn a large national US sample, employer requirements were associated with higher and more equitable HCP vaccination uptake across all sociodemographic groups examined. Our findings suggest that employer requirements can contribute to improving COVID-19 vaccination coverage, similar to patterns seen for other vaccines.

5.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-958860

RESUMEN

Objective: To observe the effect of electroacupuncture (EA) at different time points during the perioperative period on the recovery of gastrointestinal function after gastrointestinal malignant neoplasms surgery. Methods: Sixty-three patients who needed radical surgery for gastrointestinal tumors were randomized into a control group, treatment group 1 (postoperative EA group), and treatment group 2 (intraoperative and postoperative EA group). The control group received surgery and conventional Western medicine treatment, and treatment groups 1 and 2 received additional EA treatment at different time points. The initial flatus time after the surgery, visual analog scale (VAS) score at different time points after the surgery, the proportion of using patient-controlled analgesia (PCA) after the surgery, and the times of adding analgesics were observed in the three groups. Results: The initial flatus time after the surgery was earlier in treatment groups 1 and 2 than in the control group (P<0.05); the difference between treatment groups 1 and 2 was statistically insignificant (P>0.05). The VAS score was lower in treatment group 2 than in the control group at 6, 12, 24, and 72 h after the surgery (P<0.05); the VAS score was lower in treatment group 1 than in the control group only at 72 h after the surgery (P<0.05). There were no significant differences in the rate of using PCA among the three groups (P>0.05). Regarding the times of adding analgesics, it was less in treatment group 2 than in the control group at 12 h after the surgery (P<0.05). Conclusion: Either EA during and after the surgery or only after the surgery can hasten the initial flatus and boost the recovery of gastrointestinal function in patients after radical resection of gastrointestinal neoplasms. Successive EA during and after the surgery should be superior to postoperative EA regarding the analgesic effect after the surgery.

6.
Chinese Journal of Neuromedicine ; (12): 989-995, 2021.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1035517

RESUMEN

Objective:To investigate the clinical value of free-talk language functional cortex mapping methods based on high frequency response in epileptic foci resection.Methods:Twenty patients with intractable epilepsy admitted to our hospital from January 2016 to May 2019 were chosen in our study. According to the different intraoperative mapping methods of language functional region, these patients were divided into test group ( n=10, using free-talk language function localization based on high frequency response [new method]+ electrical cortical stimulation [ECS]) and control group ( n=10, using ECS localization only). The overlap rate of the two methods in the test group were calculated and the postoperative follow-up results of patients in the two groups were analyzed. Results:In 10 patients from the test group, 33 positive loci in the Broca's area and 33 positive loci in the Wernicke's area were detected by new method; at the meantime, 16 positive loci in the Broca's area and 8 positive loci in the Wernicke's area were detected by ECS method, which had a overlap rate of 93.75% (15/16) in the Broca's area and 75.00% (6/8) in the Wernicke's area, respectively, as compared with the new method. In the 10 patients from the control group, 18 positive loci in the Broca's area and 3 positive loci in the Wernicke's area were detected by ECS method. In the test group, 7 patients achieved Engel grading I and 2 patients developed transient language function impairment after surgery; while in the control group, 5 patients achieved Engel grading I and 4 patients developed transient language function impairment after surgery.Conclusion:The new method has a high overlap rate with ECS method; the combination of the two methods can help to decrease the speech function impairment after excision of epileptogenic foci in patients with epilepsy.

7.
Acta Pharmaceutica Sinica B ; (6): 484-495, 2019.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-774961

RESUMEN

Metastasis-associated drug resistance accounts for high mortality in ovarian cancer and remains to be a major barrier for effective treatment. In this study, SKOV3/T4, a metastatic subpopulation of ovarian cancer SKOV3 cells, was enriched to explore potential interventions against metastatic-associated drug resistance. Quantitative genomic and functional analyses were performed and found that slug was significantly increased in the SKOV3/T4 subpopulation and contributed to the high resistance of SKOV3/T4. Further studies showed that slug activated c-Met in a ligand-independent manner due to elevated levels of fibronectin and provoked integrin V function, which was confirmed by the significant correlation of slug and p-Met levels in 121 ovarian cancer patient samples. Intriguingly, c-Met inhibitor(s) exhibited greatly enhanced anti-cancer effects in slug-positive ovarian cancer models both and . Additionally, IHC analyses revealed that slug levels were highly correlated with reduced survival of ovarian cancer patients. Taken together, this study not only uncovers the critical roles of slug in drug resistance in ovarian cancer but also highlights a promising therapeutic strategy by targeting the noncanonical activation of c-Met in slug-positive ovarian cancer patients with poor prognosis.

8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-707430

RESUMEN

Objective To investigate biomechanical properties of the patella tension plating system in order to provide a theoretical basis for its clinical application. Methods Thirty-six models of artificial patella were randomly divided into 3 groups ( n=12 ) . After transverse patellar fractures were created in the models, the 3 groups were subjected to fixation respectively with Kirschner wire tension band ( tension band group ) , patellar concentrator ( concentrator group ) and patellar tension plate ( tension plate group ) . Next, 6 specimens from each group were placed on a mechanical testing machine to measure the fracture displacements after 100 cycles of simulated knee flexion and extension movements. Tensile strength tests were performed on the remaining 6 specimens in each group to measure the maximum load at fixation failure. Results The fracture displacement in the tension plate group ( 0. 40 ± 0. 26 mm ) was significantly smaller than those in the tension band group ( 2. 58 ± 0. 72 mm ) and in the concentrator group ( 1. 25 ± 0. 74 mm ) ( P < 0. 05 );the maximum load at fixation failure in the tension plate group ( 1 , 709 ± 206 N ) was significantly greater than those in the tension band group ( 581 ± 122 N ) and in the concentrator group ( 1, 003 ± 211 N ) ( P <0. 05 ) . Conclusion As a new treatment for patellar fractures, the patellar tension plating system can perform better in biomechanical properties than Kirschner wire tension band and patellar concentrator.

9.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-508219

RESUMEN

BACKGROUND: There are various treatment methods for femoral neck fracture in the elderly, and they have advantages and disadvantages, especially for the elderly type of stable femoral neck fractures Garden type II of treatment options. OBJECTIVE: To summarize the current main clinical methods of senile femoral neck fractures of Garden type II, compare the advantages and disadvantages of internal fixation and joint replacement, and provide the best treatment for orthopedic surgeons. METHODS: We retrieved PubMed database. Key words were elderly femoral neck fracture, Garden type II, selection strategy and progress. Combining with the clinical cases encountered in the comparative analysis, the relevant discussion was analyzed. RESULTS AND CONCLUSION: Although the risk of surgery and the pain of non-surgical patients in early stage, the effects are not ideal. Internal fixation of Garden type II femoral neck fracture and joint replacement in elderly patients is controversial. For the elderly and Garden type II femoral neck fractures, the rate of revision after cannulated screw fixation was significantly higher than that of hip replacement. Both cement-type and biological-type implant prosthesis can improve hip function largely, and reduce non-surgical complications, and finally get a satisfactory clinical effect. The clinician should make the best treatment plan according to the patient’s age, bone condition, fracture type and physical condition.

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