Estimation of Pesticide Residues on Leafy Vegetables Using a Developed Handheld Spectrometer

In this study, a rapid and non-destructive detection model for pesticide residues on leafy vegetables was presented using a developed portable spectrometer. VIS/NIR spectra of three vegetable samples, including lettuce, oriental mustard, and bok choy, were analyzed at the range of 380 – 840 nm. Stepwise multiple linear regression (SMLR) models were developed based on chemical reference measurements and the spectral information of the leaf samples after performing the pre-processing method. Furthermore, a data acquisition interface was developed by Matlab GUI. Results of SMLR procedure indicated good performance for detection of indoxacarb and chlorantraniliprole with R2 ≥ 0.90. A fairly good model (0.90 > R2 > 0.80) was obtained for carbendazim in lettuce, whereas a poor model was found for emamectin-benzoate with R2 ≤ 0.80. It was concluded that pesticide residues on leafy vegetables could be predicted using our developed handheld spectrometer. It can also be generalized for the prediction of other pesticide components in agricultural products.

Stepwise multiple linear regression applied to study the influence of pedestrian volumes according to environmental characteristics

Desde comienzos de los años 90, la evolución de los factores socioeconómicos, locales y regionales en la sociedad occidental ha hecho que el peatón se convierta en el foco de los planes de movilidad urbanos llevados a cabo hasta la actualidad. Esto se puede comprobar considerando las numerosas investigaciones realizadas en este ámbito donde se evidencia la necesidad de fundamentar la relación existente entre el planeamiento urbano y la salud de las personas. Pese a que se han propuesto numerosas metodologías para analizar estas relaciones, se observa que aquella que se da entre el volumen de peatones en una zona y las características del entorno dan mejores resultados, aunque partan de modelos multivariables difíciles de calcular. El propósito de este artículo pretende recopilar y reducir aquellas variables que afecten de manera significativa a los movimientos poblacionales en función del nivel comercial de la zona de estudio. Para ello, se utilizará entre los diferentes modelos matemáticos existentes, el de regresión lineal escalonado. Finalmente, se concluye que la conectividad y el mobiliario urbano en áreas primarias, la presencia de bares y oficinas en áreas secundarias y la conectividad, densidad residencial y zonas de uso mixto en áreas terciarias son factores clave que deberán ser consideraros en la planificación futura de las zonas estudiadas.

Global Burden of Cataract and Its Association With Socioeconomic Development Status, 1990-2019

Background: Cataract is the leading cause of blindness globally and more people will be at risk for this common cause of vision loss in the coming years.To estimate the disease burden of cataract and evaluate contributions of various risk factors to cataract-associated disability-adjusted life years (DALYs).Methods: Prevalence of visual impairment due to cataract and disability-adjusted life years of cataract were extracted from the Global Burden of Disease (GBD) study 2019 to explore time trends and annual changes. Regional and country-level socioeconomic indexes were acquired from open databases, and stepwise multiple linear regression was used to evaluate associations between age-standardized rate of DALYs of cataract and potential predictors.Results: Global Prevalence rate of visual impairment due to cataract rose by 58.45% from 791.4 per 100,000 population (95%CI: 705.2 to 890.0 per 100,000 population) to 1253.9 per 100,000 population 95%CI: 1103.3 to 1417.7 per 100,000 population) in 2019 and DALYs rate of cataract rose by 32.18% from 65.3 per 100,000 population (95%CI: 46.4 to 88.2 per 100,000 population) in 1990 to 86.3 per 100,000 population (95%CI: 61.5 to 116.4 per 100,000 population) in 2019.Stepwise multiple linear regression model showed that higher refractive error prevalence (β=0.036, 95% CI: 0.022, 0.050, P<0.001), lower number of physicians per 10,000 population (β=-0.959, 95% CI: -1.685, -0.233, P=0.010) and lower level of HDI (β=-134.93, 95% CI: -209.84, -60.02, P=0.001) were associated with higher disease burden of cataract.Conclusions: Substantial increases in the prevalence of visual impairment and DALYs of cataract were observed from 1990 to 2019. Successful global initiatives targeting improving cataract surgical rate and quality, especially in regions with lower socioeconomic status, is a prerequisite to combating this growing burden of cataract in the aging society.

Use of Low-Flow Flowmeter to Titrate the FiO2 Delivered in Neonatal Resuscitation

Introduction: The oxygen concentration used in neonatal resuscitation has been a matter of debate with higher oxygen concentrations posing many adverse outcomes. Recent guidelines recommend use of blender to titrate FiO2 delivered during resuscitation. However, blender being unaffordable and unavailable at many peripheral institutions, we tried to use a low-flow flowmeter to titrate the oxygen and measure FiO2 delivered at different flow rates. Methods: From a central oxygen supply, oxygen flow was titrated using a low-flow flowmeter which was connected to a self-inflating bag and oximeter. Three variables were taken—volume of self-inflating bag, flow rate, and number of compressions per minute. FiO2 delivered with each variable, keeping the other two constant, was recorded. Results: The data obtained was analyzed by fitting the study variables into a stepwise multiple linear regression model and a linear equation was obtained. The model R square obtained suggested strong linear relationship between flow rate and FiO2 delivered. The model showed statistically significant association between flow rate and FiO2 delivery, whereas association with other variables was statistically insignificant. Discussion: Our study suggests that 76.57% of change in FiO2 is determined by change in flow rate. The major advantage of this study would be at resource poor settings where a low-flow flowmeter which is more cost effective can be used to titrate the FiO2 delivered during neonatal resuscitation.

Using hand grip strength to detect slow walking speed in older adults: the Yilan study

Background Walking speed is an important health indicator in older adults, although its measurement can be challenging because of the functional decline due to aging and limited environment. The aim of this study was to examine whether hand grip strength can be a useful proxy for detecting slow walking speed in this population. Methods A cross-sectional study was conducted using the cohort from the Yilan Study in Taiwan. Community-dwelling older adults aged 65 years and older were included. Slow walking speed was defined as a 6-meter walking speed < 1.0 m/s, according to the 2019 Asian Working Group for Sarcopenia diagnostic criteria. Stepwise multiple linear regression was used to determine the most significant variables associated with walking speed. Receiver operating characteristic analysis was used to determine the optimal cutoff values for hand grip strength in detecting slow walking speed. Results A total of 301 participants with an average age of 73.9 ± 6.8 years were included; 55.1 % participants were women. In stepwise multiple linear regression analysis that included various variables, hand grip strength was found to be the most explainable factor associated with walking speed among all participants and among participants of each sex. The optimal cutoff values for hand grip strength in the detection of slow walking speed were 19.73 kg for all participants (sensitivity: 55 %, specificity: 83 %, area under the curve: 0.74, accuracy: 66.9 %), 35.10 kg for men (sensitivity: 92 %, specificity: 42 %, area under the curve: 0.70, accuracy: 66.4 %), and 17.93 kg for women (sensitivity: 62 %, specificity: 80 %, area under the curve: 0.76, accuracy: 67.9 %). Conclusions Hand grip strength was found to be a useful proxy for the identification of slow walking speed in older adults.

Disease Burden of Chronic Kidney Disease Due to Hypertension From 1990 to 2019: A Global Analysis

Background: Although it is widely known that hypertension is an important cause of chronic kidney disease (CKD), little detailed quantitative research exists on the burden of CKD due to hypertension.Objective: The objective of the study is to estimate the global disease burden of CKD due to hypertension and to evaluate the association between the socioeconomic factors and country-level disease burden of CKD due to hypertension.Methods: We extracted the disability-adjusted life-year (DALY) numbers, rates, and age-standardized rates of CKD due to hypertension from the Global Burden of Disease Study 2019 database to investigate the time trends of the burden of CKD due to hypertension from 1990 to 2019. Stepwise multiple linear regression analysis was performed to evaluate the correlations between the age-standardized DALY rate and socioeconomic factors and other related factors obtained from open databases.Results: Globally, from 1990 to 2019, DALY numbers caused by CKD due to hypertension increased by 125.2% [95% confidential interval (CI), 124.6 to 125.7%]. The DALY rate increased by 55.7% (55.3 to 56.0%) to 128.8 (110.9 to 149.2) per 100,000 population, while the age-standardized DALYs per 100,000 population increased by 10.9% (10.3 to 11.5%). In general, males and elderly people tended to have a higher disease burden. The distribution disparity in the burden of CKD due to hypertension varies greatly among countries. In the stepwise multiple linear regression model, inequality-adjusted human development index (IHDI) [β = −161.1 (95% CI −238.1 to −84.2), P &lt; 0.001] and number of physicians per 10,000 people [β = −2.91 (95% CI −4.02 to −1.80), P &lt; 0.001] were significantly negatively correlated with age-standardized DALY rate when adjusted for IHDI, health access and quality (HAQ), number of physicians per 10,000 people, and population with at least some secondary education.Conclusion: Improving the average achievements and equality of distribution in health, education, and income, as well as increasing the number of physicians per 10,000 people could help to reduce the burden of CKD due to hypertension. These findings may provide relevant information toward efforts to optimize health policies aimed at reducing the burden of CKD due to hypertension.

Optimized Surgical Strategy for Adult Spinal Deformity: Quantitative Lordosis Correction versus Lordosis Morphology

Background: In surgical correction of adult spinal deformity (ASD), pelvic incidence (PI)-lumbar lordosis (LL) plays a key role to restore normal sagittal alignment. Recently, it has been found that postoperative lordosis morphology act as an important factor in preventing mechanical complications. However, there have been no studies on the effect of postoperative lordosis morphology on the restoration of sagittal alignment. The primary objective of this study was to evaluate the effect of postoperative lordosis morphology on achievement of optimal sagittal alignment. The secondary objective was to find out which radiographic or morphologic parameter affects sagittal alignment in surgical correction of ASD. Methods: 228 consecutive patients with lumbar degenerative kyphosis who underwent deformity correction and long-segment fixation from T10 to S1 with sacropelvic fixation and follow-up over 2 years were enrolled. Patients were divided according to whether optimal alignment was achieved (balanced group) or not (non-balanced group) at last follow-up. We analyzed the differences of postoperative radiographic parameters and morphologic parameters between two groups. Correlation analysis and stepwise multiple linear regression analysis was performed to predict the effect of PI-LL and morphologic parameters on the sagittal vertical axis (SVA). Results: Of 228 patients, 195 (85.5%) achieved optimal alignment at last follow-up. Two groups significantly differed in postoperative and last follow-up LL (p < 0.001 and p = 0.028, respectively) and postoperative and last follow-up PI-LL (p < 0.001 and p = 0.001, respectively). Morphologic parameters did not significantly differ between the two groups except lower lordosis arc angle (=postoperative sacral slope). In correlation analysis and stepwise multiple linear regression analysis, postoperative PI-LL was the only parameter which had significant association with last follow-up SVA (R2 = 0.134, p < 0.001). Morphologic parameters did not have any association with last follow-up SVA. Conclusions: When planning spine reconstruction surgery, although considering postoperative lordosis morphology is necessary, it is still very important considering proportional lordosis correction based on individual spinopelvic alignment (PI-LL) to achieve optimal sagittal alignment.

Modeling and Spatialization of Biomass and Carbon Stock Using LiDAR Metrics in Tropical Dry Forest, Brazil

In recent years, with the growing environmental concern regarding climate change, there has been a search for efficient alternatives in indirect methods for the quantification of biomass and forest carbon stock. In this article, we seek to obtain pioneering results of biomass and carbon estimates from forest inventory data and LiDAR technology in a dry tropical forest in Brazil. We use forest inventory data in two areas together with data from the LiDAR flyby, generating estimates of local biomass and carbon levels obtained from local species. We approach three types of models for data analysis: Multiple linear regression with principal components (PCA), conventional multiple linear regression and stepwise multiple linear regression. The best fit total above ground biomass (TAGB) and total above ground carbon (TAGC) model was the stepwise multiple linear regression, concluding, then, that LiDAR data can be used to estimate biomass and total carbon in dry tropical forest, proven by an adjustment considered in the models employed, with a significant correlation between the LiDAR metrics. Our finding provides important information about the spatial distribution of TAGB and TAGC in the study area, which can be used to manage the reserve for optimal carbon sequestration.