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Ensemble learning of model hyperparameters and spatiotemporal data for calibration of low-cost PM2.5 sensors.
he PM2.5 air quality index (AQI) measurements from government-built supersites are accurate but cannot provide a dense coverage of monitoring areas. Low-cost PM2.5 sensors can be used to deploy a fine-grained internet-of-things (IoT) as a complement to government facilities. Calibration of low-cost sensors by reference to high-accuracy supersites is thus essential. Moreover, the imputation for missing-value in training data may affect the calibration result, the best performance of calibration model requires hyperparameter optimization, and the affecting factors of PM2.5 concentrations such as climate, geographical landscapes and anthropogenic activities are uncertain in spatial and temporal dimensions. In this paper, an ensemble learning for imputation method selection, calibration model hyperparameterization, and spatiotemporal training data composition is proposed. Three government supersites are chosen in central Taiwan for the deployment of low-cost sensors and hourly PM2.5 measurements are collected for 60 days for conducting experiments. Three optimizers, Sobol sequence, Nelder and Meads, and particle swarm optimization (PSO), are compared for evaluating their performances with various versions of ensembles. The best calibration results are obtained by using PSO, and the improvement ratios with respect to R2, RMSE, and NME, are 4.92%, 52.96%, and 56.85%, respectively
CCN2 Enhances Resistance to Cisplatin-Mediating Cell Apoptosis in Human Osteosarcoma
Osteosarcoma (OS) is the most common form of malignant bone tumor and is an aggressive malignant neoplasm exhibiting osteoblastic differentiation. Cisplatin is one of the most efficacious antitumor drugs for osteosarcoma patients. However, treatment failures are common due to the development of chemoresistance. CCN2 (also known as CTGF), is a secreted protein that binds to integrins, modulates the invasive behavior of certain human cancer cells. However, the effect of CCN2 in cisplatin-mediated chemotherapy is still unknown. Here, we found that CCN2 was upregulated in human osteosarcoma cells after treatment with cisplatin. Moreover, overexpression of CCN2 increased the resistance to cisplatin-mediated cell apoptosis. In contrast, reduction of CCN2 by CCN2 shRNA promoted the chemotherapeutic effect of cisplatin. We also found that CCN2 provided resistance to cisplatin-induced apoptosis through upregulation of Bcl-xL and survivin. Knockdown of Bcl-xL or survivin removed the CCN2-mediated resistance to apoptosis induced by cisplatin. On the other hand, CCN2 also promoted FAK, MEK, and ERK survival signaling pathways to enhance tumor survival during cisplatin treatment. In a mouse xenograft model, overexpression of CCN2 promoted resistance to cisplatin. However, knockdown of CCN2 increased the therapeutic effect of cisplatin. Therefore, our data suggest that CCN2 might be a critical oncogene of human osteosarcoma for cisplatin-resistance and supported osteosarcoma cell growth in vivo and in vitro
Total Parenteral Nutrition Treatment in a Diabetic Pregnant Woman Complicated with Hyperemesis Gravidarum, Malnutrition, and Intrauterine Growth Restriction
SummaryObjectiveWe report a case of a pregnant woman with diabetes, complicated with hyperemesis gravidarum, malnutrition, and intrauterine growth restriction, who was treated beneficially with total parenteral nutrition.Case ReportA 26-year-old diabetic nullipara complained of severe nausea and vomiting from early in her pregnancy. Malnutrition developed at about 24 weeks of gestation. In spite of treatment with antiemetics, antihistamine, and vitamin B6, the symptoms persisted, and intrauterine growth restriction eventually developed. Total parenteral nutrition was commenced at 29 weeks of gestation. She delivered a healthy female neonate with a birth body weight of 2,120 g at 36 weeks of gestation by cesarean section. Total parenteral nutrition was gradually tapered off 1 week later, and the mother was discharged from hospital in good condition 10 days after delivery.ConclusionTotal parenteral nutrition may be used to treat diabetic patients with hyperemesis gravidarum who develop malnutrition causing intrauterine growth restriction
Overexpression of PCNA Attenuates Oxidative Stress-Caused Delay of Gap-Filling during Repair of UV-Induced DNA Damage
Enhancing the in vivo transdermal delivery of gold nanoparticles using poly(ethylene glycol) and its oleylamine conjugate
Thrombolysis in Myocardial Infarction Frame Count in Single-Vessel Disease After Angioplasty
SUMMARYBackgroundWe compared the thrombolysis in myocardial infarction (TIMI) frame count and examined the impact of angioplasty on the count between patients with normal coronary angiograms and those with single-vessel disease (SVD).MethodsIn 780 consecutive patients referred for coronary angiography, TIMI frame count was measured for 149 patients who had SVD and 32 patients with normal angiograms who underwent the procedure for electro-physiologic study or valvular heart disease survey.ResultsComparison of each of the three vessels in the normal vessel group with the corresponding non-stenotic vessels in the SVD group showed similar counts in each of the left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA). For the stenotic vessels, after successful angioplasty, the counts were all reduced (LAD, 54.5 ±28.8 vs. 34.0 ±19.3; LCX, 67.3 ±31.1 vs. 34.1 ±19.0; RCA, 33.2 ±28.1 vs. 19.3 ±7.9; all p <0.05). In addition, the count in the RCA after angioplasty was lower, compared with the RCA of the normal group (19.3 ±7.9 vs. 29.1 ±14.6, p = 0.001). Multivariate analysis showed that the use of oral calcium channel blockers was the only independent predictor for the reduction in RCA after angioplasty.ConclusionIn patients with SVD, the data of TIMI frame count in the nonstenotic vessels were similar to those without the disease, suggesting that the count in the normal artery is not affected by the adjacent stenotic artery. For the stenotic vessels, angioplasty had differential effects on each of the three arteries, indicating the existence of distinct properties, which is affected by calcium channel blockers, for individual coronary arteries in response to atherosclerosis and/or angioplasty
Smoking, Habitual Tea Drinking and Metabolic Syndrome in Elderly Men Living in Rural Community: The Tianliao Old People (TOP) Study 02
The literature shows an inconsistent relationship between lifestyle behaviors and metabolic syndrome (MetS), especially in the elderly. We designed this study to investigate the interrelationships among cigarette smoking, tea drinking and MetS, and to verify the factors associated with MetS in elderly males dwelling in rural community. In July 2010, with a whole community sampling method, 414 male subjects aged over 65 dwelling in Tianliao township were randomly sampled. The response rate was 60.8%. Each subject completed the structured questionnaires including sociodemographic characteristics, habitual behaviors (including cigarette smoking and tea drinking habits) and medical history. After an overnight fast, the laboratory and anthropometric data were obtained. MetS was confirmed according to the criteria defined by the modified NCEP ATP III for the male Chinese population. Subjects were split into either non-MetS or MetS groups for further analysis. Of the 361 subjects with complete data, 132 (36.6%) elderly men were classified as having MetS. Using binary logistic regression, body mass index, serum uric acid, high sensitivity C-reactive protein, HOMA index, current smokers (OR = 2.72, 95%CI: 1.03 ∼ 7.19), total smoking amount > = 30 (OR = 2.78, 95%CI: 1.31 ∼ 5.90) and more than 20 cigarettes daily (OR = 2.54, 95%CI: 1.24 ∼ 5.18) were positively associated with MetS. Current un- or partial fermented tea drinker (OR = 0.42, 95%CI: 0.22 ∼ 0.84), tea drinking habit for 1–9 years (OR = 0.36, 95%CI: 0.15 ∼ 0.90) and more than 240cc daily (OR = 0.35, 95%CI: 0.17 ∼ 0.72) were negatively associated with MetS. In conclusion, this study suggests that smoking habit was positively associated with MetS, but tea drinking habit was negatively associated with MetS in elderly men dwelling in rural community
Deep ocean mineral supplementation enhances the cerebral hemodynamic response during exercise and decreases inflammation postexercise in men at two age levels.
Background: Previous studies have consistently shown that oral supplementation of deep ocean minerals (DOM) improves vascular function in animals and enhances muscle power output in exercising humans. Purpose: To examine the effects of DOM supplementation on the cerebral hemodynamic response during physical exertion in young and middle-aged men. Design: Double-blind placebo-controlled crossover studies were conducted in young (N = 12, aged 21.2 ± 0.4 years) and middle-aged men (N = 9, aged 46.8 ± 1.4 years). The counter-balanced trials of DOM and Placebo were separated by a 2-week washout period. DOM and Placebo were orally supplemented in drinks before, during, and after cycling exercise. DOM comprises desalinated minerals and trace elements from seawater collected ~618 m below the earth's surface. Methods: Cerebral hemodynamic response (tissue hemoglobin) was measured during cycling at 75% VO2max using near infrared spectroscopy (NIRS). Results: Cycling time to exhaustion at 75% VO2max and the associated plasma lactate response were similar between the Placebo and DOM trials for both age groups. In contrast, DOM significantly elevated cerebral hemoglobin levels in young men and, to a greater extent, in middle-aged men compared with Placebo. An increased neutrophil to lymphocyte ratio (NLR) was observed in middle-aged men, 2 h after exhaustive cycling, but was attenuated by DOM. Conclusion: Our data suggest that minerals and trace elements from deep oceans possess great promise in developing supplements to increase the cerebral hemodynamic response against a physical challenge and during post-exercise recovery for middle-aged men.This work was supported by Pacific Deep Ocean Biotech (Taipei,Taiwan) and University of Taipei (Taipei, Taiwan). The funding sponsors had no role in the design of the study; in the of the manuscript, and in the decision to publish the results. We declare that the results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation
Nondestructive quantitative analysis of water potential of tomato leaves using online hyperspectral imaging system
Tomatoes have different water requirements in each growing period. Excessive water use or insufficient water
supply will affect the growth and yield of tomato plants. Therefore, precise irrigation control is necessary during cultivation
to increase crop productivity. Traditionally, the soil moisture content or leaf water potential has been used as an indicator
of plant water status. These methods, however, have limited accuracy and are time-consuming, making it difficult to be put
into practice in tomato production. This study developed an online hyperspectral imaging system to measure the leaf water
potential of tomato nondestructively. Linear Discriminant Analysis was utilized to automatically and quickly extract the leaf
images, with the recognition accuracy of 94.68% was achieved. The mathematical processing of Standard Normal Variate
scattering correction was used to remove the spectral variations caused by the defocused leave images. The developed leaf
water potential prediction model based on the spectral image information attained using the developed system achieved the
standard error of calibration of 0.201, coefficient of determination in calibration set of 0.814 and standard error of cross�validation of 0.230, and one minus the variance ratio of 0.755. The obtained performance indicated the feasibility of apply�ing the developed online hyperspectral imaging system as a real-time non-destructive measurement technique for the leaf
water potential of tomato plants
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