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With one operational amplifier (op-amp) in negative feedback, the traditional zero potential circuit could access one element in the two-dimensional (2-D) resistive sensor array with the shared row-column fashion but it suffered from the crosstalk problem for the non-scanned elements' bypass currents, which were injected into array's non-scanned electrodes from zero potential. Firstly, for suppressing the crosstalk problem, we designed a novel improved zero potential circuit with one more op-amp in negative feedback to sample the total bypass current and calculate the precision resistance of the element being tested (EBT) with it. The improved setting non-scanned-electrode zero potential circuit (S-NSE-ZPC) was given as an example for analyzing and verifying the performance of the improved zero potential circuit. Secondly, in the S-NSE-ZPC and the improved S-NSE-ZPC, the effects of different parameters of the resistive sensor arrays and their readout circuits on the EBT's measurement accuracy were simulated with the NI Multisim 12. Thirdly, part features of the improved circuit were verified with the experiments of a prototype circuit. Followed, the results were discussed and the conclusions were given. The experiment results show that the improved circuit, though it requires one more op-amp, one more resistor and one more sampling channel, can access the EBT in the 2-D resistive sensor array more accurately.
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Noisy labels are often encountered in datasets, but learning with them is challenging. Although natural discrepancies between clean and mislabeled samples in a noisy category exist, most techniques in this field still gather them indiscriminately, which leads to their performances being partially robust. In this paper, we reveal both empirically and theoretically that the learning robustness can be improved by assuming deep features with the same labels follow a student distribution, resulting in a more intuitive method called student loss. By embedding the student distribution and exploiting the sharpness of its curve, our method is naturally data-selective and can offer extra strength to resist mislabeled samples. This ability makes clean samples aggregate tightly in the center, while mislabeled samples scatter, even if they share the same label. Additionally, we employ the metric learning strategy and develop a large-margin student (LT) loss for better capability. It should be noted that our approach is the first work that adopts the prior probability assumption in feature representation to decrease the contributions of mislabeled samples. This strategy can enhance various losses to join the student loss family, even if they have been robust losses. Experiments demonstrate that our approach is more effective in inaccurate supervision. Enhanced LT losses significantly outperform various state-of-the-art methods in most cases. Even huge improvements of over 50% can be obtained under some conditions.
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AIM: To evaluate the efficacy and safety of ultrasound cycloplasty (UCP) for glaucoma. METHODS: A comprehensive search of PubMed, Embase, Web of Science, and Google Scholar databases was used to select studies met the inclusion criteria. Meta-analysis was performed by Review Manager and StataCorp LLC. RESULTS: A total of 19 articles met the inclusion criteria. Overall, UCP is effective and safe in the glaucoma treatment, the risk ratio (RR) of the success rate was 2.28 (95%CI, 1.82-2.84). After UCP, patients had a significant reduction in intraocular pressure (IOP; mm Hg), the weighted mean difference (WMD) was 11.39 (95%CI, 9.88-12.90). In addition, UCP brings fewer postoperative complications with RR of 0.30 (95%CI, 0.19-0.49). Most of the complications were short-term and mild. Postoperatively, patients' use of IOP-lowering medications reduced, the standardized mean difference (SMD) was 0.78 (95%CI, 0.40-1.17). However, best corrected visual acuity (BCVA; logMAR) did not have obvious improvement after UCP, the WMD was 0.01 (95%CI, -0.06-0.09). This procedure does provide painfulness relief, with RR of 3.06 (95%CI, 1.95-4.81). CONCLUSION: UCP is effective and safe for suitable glaucoma. It can effectively decrease IOP in glaucoma patients, reduce the patients' dependence on IOP-lowering medications after surgery, relief the painfulness and has fewer long-term or severe postoperative complications, but the BCVA did not improve much.
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AIM: To evaluate the trends and changes in the number and rates of disability-adjusted life years (DALYs) and prevalence of cataract in China between 1990 and 2019, and to predict the trends of cataract burden from 2020 to 2030. METHODS: The Global Burden of Diseases (GBD) database was employed to collect the data on DALYs and the prevalence of cataract in China, which was distinguished by age and sex during the past three decades from 1990 to 2019, and then changes in the number and rates of cataract from 2020 to 2030 were predicted. All data were analyzed by the R program (version 4.2.2) and GraphPad Prism 9.0 statistics software. RESULTS: The number of DALYs of cataract increased from 449 322.84 in 1990 to 1 087 987.61 in 2019, number of cataract cases increased from 5 607 600.94 in 1990 to 18 142 568.96 in 2019. The age-standardized DALY rates (ASDR) generally increased slightly [estimated annual percentage change (EAPC=0.1; 95%CI: -0.24 to 0.45), age-standardized prevalence rates (ASPR) also increased (EAPC=0.88; 95%CI: 0.6 to 1.15). Cataract burden increased with age and female gender. Among the causes of cataract, air pollution was the most important, followed by smoking, high fasting plasma glucose, and high body mass index (BMI). The burden of cataract is predicted to grow persistently from 2020 to 2030, the number of DALYs and prevalence for cataract will rise to 2 336 431 and 43 698 620 respectively by 2030, the ASDR is predicted to be 85/100 000 and ASPR will be 1586/100 000 in 2030, females will still be at greater risk of suffering from cataract than males. CONCLUSION: The burden of cataract in China kept rising from 1990 to 2019. Increasing age and female gender are risk factors for cataract. Air pollution, smoking, high fasting plasma glucose, and high BMI are associated with cataract. The burden of cataract in China will gradually increase from 2020 to 2030, the elderly women in particular need attention. Our results may be of help for providing reference strategies to reduce cataract burden in the near future.
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AIM: To predict postoperative intraocular lens (IOL) position using the Sirius anterior segment analysis system and investigate the effect of lens position and IOL type on postoperative refraction. METHODS: A total of 97 patients (102 eyes) were enrolled in the final analysis. An anterior segment biometry measurement was performed preoperatively with Sirius and Lenstar. The results of predicted lens position (PLP) and IOL power were automatically calculated by the software used by the instruments. Effective lens position (ELP) was measured manually using Sirius 3mo postoperatively. Pearson's correlation analysis and linear regression analysis were used to determine the correlation of lens position to other parameters. RESULTS: PLP and ELP were positively correlated to axial length (AL; r=0.42, P<0.0001 and r=0.49, P<0.0001, respectively). There was a weak correlation between the peLP (ELP-PLP) and the prediction error of spherical refraction (peSR; r=0.34, P<0.0001). The peLP of Softec HD IOL differed statistically from those of both the TECNIS ZCB00 and Sensor AR40E IOLs. Multiple linear regression was used to obtain the prediction formula: ELP=0.66+0.63×[aqueous depth (AQD)+0.6LT] (r=0.61, P<0.0001), and a new variable (AQD+0.6 LT) was found to have the strongest correlation with ELP. CONCLUSION: The Sirius anterior segment analysis system is helpful to predict ELP, which reduces postoperative refraction error.
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The present article studied the interaction between intramolecular charge transfer fluorescence probe-1-keto-2-(p-dimethylaminobenzal)-tetrohydronaphthalene (KDTN) and bovine serum albumins (BSA). With the concentration of KDTN increasing, the fluorescence of BSA rapidly quenched and the fluorescence peak gradually blue-shifted. The result indicated that they were bound mainly by hydrophobic interaction. The binding sites is 0.94 (3 degrees C) and the equilibrium constant K is 3.27 x 10(4) L x mol(-1). Temperature increment is advantageous to the combination. It is a single static quenching process that the fluorescence of BSA quenches, which is induced by the combination of KDTN and BSA. Further study showed that different substances had different effects on the combination of KDTN and BSA.
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Naftalenos/análise , Soroalbumina Bovina/análise , Espectrometria de Fluorescência/métodos , Animais , Bovinos , Estrutura Molecular , Naftalenos/química , Soroalbumina Bovina/química , TemperaturaRESUMO
The fluorescence characteristics of the interaction between DNA and two halogen fluoresceins, tetrabromofluorescein (TBF) and tetrachlorotetrabromofluorescein (TTF), were studied. The result showed that for TBF, lamda ex/ lamda em were 518 nm/540 nm, and for TTF, they were 540 nm/560 nm. The intensity of fluorescence of TBF and TTF changed in the presence of DNA. The fluorescence quenching studies indicated that TBF binds to DNA in the groove and the polarization experiments showed that TBF is intercalated into the DNA base pairs. So the comprehensive interaction mode of TBF with DNA may be that TTF is intercalated into DNA base pairs and binds to DNA in the groove. Both the fluorescence quenching studies and the polarization experiments indicated that TTF is intercalated into the DNA base pairs. It was also found that ionic strength could affect the interaction of TBF/TTF and DNA. The binding constants K are 1 x 10(6) L x mol(-1) and 2 x 10(6) L x mol(-1), and the binding site numbers n are 0.62 and 0.16 for TBF and TTF, respectively.
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DNA/química , Amarelo de Eosina-(YS)/análise , Fluoresceínas/análise , Hidrocarbonetos Halogenados/análise , Animais , Bovinos , Amarelo de Eosina-(YS)/química , Fluoresceínas/química , Hidrocarbonetos Halogenados/química , Espectrometria de FluorescênciaRESUMO
OBJECTIVE: Ambroxol induces the synthesis of surfactant in lung alveolar type II cells. Some studies have shown its effectiveness for the prevention of respiratory distress syndrome (RDS) in preterm infants. This study aimed to compare the efficacy of two different ways of ambroxol administration, ie, intravenous injection and atomizing inhalation, for the prevention of RDS in preterm infants. METHODS: A total of 125 preterm infants born between 28-37 weeks of gestation were randomly assigned into three groups: Intravenous and Atomizing ambroxol treatment groups (n=40 each) or Control group (n=45). The Intravenous group was injected with 15 mg/kg of ambroxol through the umbilical vein immediately after birth and then received 30 mg/kg of ambroxol daily for 2 days by intravenous drip. The Atomizing group was administered with 30 mg/kg of ambroxol daily for 2 days by atomizing inhalation immediately after birth. The Control group received no ambroxol treatment. The incidences of RDS and complications as well as the blood gas results 6 hrs after birth were compared among the three groups. RESULTS: The incidence of RDS was 7.5%, 5.0% and 24.4% in the Intravenous, Atomizing and Control groups respectively. There were no significant differences in the incidence of RDS between the two ambroxol treatment groups. However, the incidence of RDS in the two treatment groups were noticeably lower than in the Control group (P < 0.05). The blood gas results did not show significant differences between the two ambroxol treatment groups but both groups demonstrated improved blood gas results compared with the Control group at 6 hrs after birth (P < 0.05). The incidence of complications, such as pulmonary hemorrhage, respiratory failure, intraranial hemorrhage, in the two ambroxol treatment groups was reduced compared with the Control group (P < 0.05), but there were no differences between the two ambroxol groups. CONCLUSIONS: Early administration of either intravenous or atomizing ambroxol can produce a positive efficacy for the prevention of RDS in preterm infants. The two different ways of administration seem to result in a similar efficacy in the prevention of RDS.
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Ambroxol/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Administração por Inalação , Ambroxol/efeitos adversos , Ambroxol/farmacologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Injeções Intravenosas , Masculino , Surfactantes Pulmonares/metabolismoRESUMO
The binding reaction of tetraiodofluorescein with bovine serum albumin i n aqueous solution was studied by fluorimetry.The binding constant is 2.65 x 10(5) L x mol(-1), the equilibrium constant is 5.7 x 10(4) L x mol(-1), and the binding number is 0.86. The research results of binding model indicate that the hydrophobic force was the main binding force. The presence of BSA can increase the fluorescence intensity of TIF. And the deltaF(F-F0) is linear to the concentration of BSA in a certain range, so the first analytical application was proposed. The linear dynamic range (LDR) was 8 x 10(-7) - 9 x 10(-6) mol x L(-1), the limit of detection (LOD) was 9.88 x 10(-8) mol x L(-1), and the relative standard deviation (RSD) was 3.4%.
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Fluoresceínas/química , Fluorometria , Soroalbumina Bovina/química , Algoritmos , Animais , Bovinos , Fluoresceínas/metabolismo , Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Cinética , Modelos Químicos , Ligação Proteica , Soroalbumina Bovina/metabolismoRESUMO
Paper-substrate delay fluorimetry (PS-DF) for three quinolones, i.e. Pefloxacin, Norfloxacin and Pepemidic acid, were given. Various factors affecting the PS-DF intensity of quinolones, including pH condition, drying time of sample etc., were studied in detail. The experiments showed that the PS-DF intensities of three quinolones in acidic solution were stronger than those in other conditions. The proper pH was 1.6. These quinolones have wide dynamic ranges, low limit of detection and relatively small standard deviations. The method was fast with, a small amount of sample and low cost. The recovery was 98.5%-104%. The determination results of the samples were satisfactory.
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Anti-Infecciosos/química , Norfloxacino/química , Pefloxacina/química , Ácido Pipemídico/química , Filtração , Concentração de Íons de Hidrogênio , Quinolonas/química , Espectrometria de Fluorescência/métodosRESUMO
The interaction between biliverdin and bovine serum albumin (BSA) has been studied by steady fluorescence spectroscopy, synchronous fluorescence and resonance light scanning spectra. The binding of biliverdin to BSA quenches the tryptophan residue fluorescence and the results show that both static and dynamic quenching occur together with complex formation. The binding constant and binding sites of biliverdin to BSA at pH 7.1 are calculated to be 3.33x10(8)L/mol and 1.54, respectively, according to the double logarithm regression curve. In addition, the distance between the biliverdin and BSA is estimated to be 1.25nm using Föster's equation on the basis of the fluorescence energy transfer. Furthermore the synchronous fluorescence spectra show that the microenvironment of the tryptophan residues has not obvious changes, which obeys the phase distribution model. Finally, the thermodynamic data show that biliverdin molecules enter the hydrophobic cavity of BSA via hydrophobic interaction.
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OBJECTIVE: To assess and analyze the risk and community treatment of hypertension in rural population of Changshu city, Jiangsu province. METHODS: A stratified cluster sampling technique was conducted to select a sample of 800 people, aged 35 - 74 years old, in a rural village according to the proportion of the national population in Changshu. Weight, height, blood pressure, serum lipid, blood glucose and other related factors were examined and analyzed. RESULTS: The prevalence rate of hypertension in the rural area was 32.01%, and significantly higher with the increase of age (P < 0.01). The average systolic blood pressure of hypertension in females was significantly positively correlated while, the average diastolic blood pressure of male and female hypertensives was significantly negatively correlated to age. The proportions of risk factors of cardiovascular diseases (CVD) as senility, hyperlipemia, premature familial history of CVD and overweight of hypertension were significantly high than those without hypertension (P < 0.01). The percentage of medium-low risk on hypertension was 85.72%, but of high risk was 14.28%. The ratio of using medication, exclusive non-medication, comprehensive treatment or total cure were 42.05%, 2.84%, 14.20% and 59.09%, accordingly. The rates of blood pressure control under the above approaches were 35.14%, 40.00%, 36.00% and 39.77%. CONCLUSION: Assessment on the risk of hypertension in the rural areas suggested that the priority should be given to medium-low risk groups, while the rate of medication and non-medicine intervention was at low level. It is necessary to strengthen a comprehensive intervention program for hypertension control.