Introducing Twitter Daily Estimates of Residents and Non-Residents at the County Level

The study of migrations and mobility has historically been severely limited by the absence of reliable data or the temporal sparsity of available data. Using geospatial digital trace data, the study of population movements can be much more precisely and dynamically measured. Our research seeks to develop a near real-time (one-day lag) Twitter census that gives a more temporally granular picture of local and non-local population at the county level. Internal validation reveals over 80% accuracy when compared with users’ self-reported home location. External validation results suggest these stocks correlate with available statistics of residents/non-residents at the county level and can accurately reflect regular (seasonal tourism) and non-regular events such as the Great American Solar Eclipse of 2017. The findings demonstrate that Twitter holds the potential to introduce the dynamic component often lacking in population estimates. This study could potentially benefit various fields such as demography, tourism, emergency management, and public health and create new opportunities for large-scale mobility analyses.

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Population Estimates from Orbital Data of Medium Spatial Resolution: Applications for a Brazilian Municipality

Sustainability ◽

10.3390/su12093565 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3565

Author(s):

Járvis Campos ◽

José Irineu Rangel Rigotti ◽

Emerson Augusto Baptista ◽

Antônio Miguel Vieira Monteiro ◽

Ilka Afonso Reis

Keyword(s):

Population Dynamics ◽

Environmental Planning ◽

External Validation ◽

Population Estimates ◽

Internal Validation ◽

Small Areas ◽

Explanatory Variables ◽

Spectral Bands ◽

Landsat 7 ◽

Orbital Data

In recent decades, there has been an increase in the search for more detailed information on population dynamics, given the growing demand for more sustainable economic, social, and environmental planning. The dissemination of Geographic Information Systems (GIS) has contributed to the development of methodologies for the field of population estimates for small areas. To support more sustainable policies, this study aims to evaluate the capacity and contribution of the orbital images (Landsat ETM+) for the production of post-census population estimates for the municipality of Contagem, Minas Gerais, Brazil. Firstly, models were built using the average of the reflectance of the spectral bands of the Landsat 7 ETM+ for each special intra-municipal unit, called the census sector, as explanatory variables for the population density. Secondly, this study constructed models that use the reflectance and the distributed population at the level of the pixels of the images. All models were tested through internal validation procedures, external validation, and comparative analyses with post-census estimates. Internal validation presented excellent results (below 7%), while in external validation, the method at the level of the pixels presented consistent results, below 1% relative error. These results provide useful clues and can help policymakers in the development of more sustainable and effective public policies, insofar as population estimates are extremely important for the planning of any society.

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Development and validation of a new diabetes index for the risk classification of present and new-onset diabetes: multicohort study

Scientific Reports ◽

10.1038/s41598-021-95341-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shinje Moon ◽

Ji-Yong Jang ◽

Yumin Kim ◽

Chang-Myung Oh

Keyword(s):

Large Scale ◽

Cox Regression ◽

Characteristic Curve ◽

External Validation ◽

High Sensitivity ◽

Population Based ◽

Risk Classification ◽

Machine Learning Techniques ◽

Internal Validation ◽

Cox Regression Analysis

AbstractIn this study, we aimed to propose a novel diabetes index for the risk classification based on machine learning techniques with a high accuracy for diabetes mellitus. Upon analyzing their demographic and biochemical data, we classified the 2013–16 Korea National Health and Nutrition Examination Survey (KNHANES), the 2017–18 KNHANES, and the Korean Genome and Epidemiology Study (KoGES), as the derivation, internal validation, and external validation sets, respectively. We constructed a new diabetes index using logistic regression (LR) and calculated the probability of diabetes in the validation sets. We used the area under the receiver operating characteristic curve (AUROC) and Cox regression analysis to measure the performance of the internal and external validation sets, respectively. We constructed a gender-specific diabetes prediction model, having a resultant AUROC of 0.93 and 0.94 for men and women, respectively. Based on this probability, we classified participants into five groups and analyzed cumulative incidence from the KoGES dataset. Group 5 demonstrated significantly worse outcomes than those in other groups. Our novel model for predicting diabetes, based on two large-scale population-based cohort studies, showed high sensitivity and selectivity. Therefore, our diabetes index can be used to classify individuals at high risk of diabetes.

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Photographic assessment of hyperdivergent class II patients

Brazilian Dental Science ◽

10.14295/bds.2015.v18i2.1092 ◽

2015 ◽

Vol 18 (2) ◽

pp. 89

Author(s):

Liliane Rosas Gomes ◽

Karla Horta ◽

Luiz Gonzaga Gandini Júnior ◽

Marcelo Gonçalves ◽

João Roberto Gonçalves

Keyword(s):

Sleep Disturbances ◽

Large Scale ◽

Low Cost ◽

External Validation ◽

Class Ii ◽

Craniofacial Morphology ◽

Photographic Method ◽

Epidemiological Research ◽

Internal Validation ◽

Lateral Cephalograms

Temporomandibular disorders, sleep disturbances by airway obstruction and craniocervical posture changes constitute some of the problems that have been related to hyperdivergent class II patients. Although cephalometric radiographs represent the gold standard for diagnosing craniofacial morphology in clinical practice, it might not be feasible for large-scale epidemiological research. Objective: The aim of this study was to test the validity of a new photographic method in diagnosing hyperdivergent class II patients for epidemiological research purposes. Material and Methods: Lateral cephalograms and profile photographs were obtained from 123 subjects assigned into two groups. 51 patients comprised the hyperdivergent class II group and the other 72 composed a second group. Discriminant analysis described a mathematical model to better diagnose hyperdivergent class II patients through photographs. Results: A canonical discriminant function composed of two photographic variables correctly classified 85% of the hyperdivergent class II patients during internal validation (p < 0.001). The method showed 83% sensitivity and 73% specificity in external validation procedure. Conclusion: The photographic method may be a feasible and practical alternative for diagnosing the hyperdivergent class II patient, particularly if there is a need for a low-cost and noninvasive method.

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The Uncertainty Principle Derived by The Finite Transmission Speed of Light and Information

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v3i3.2059 ◽

2014 ◽

Vol 3 (3) ◽

pp. 257-266 ◽

Cited By ~ 1

Author(s):

Piero Chiarelli

Keyword(s):

Uncertainty Principle ◽

Large Scale ◽

Uncertainty Relations ◽

Speed Of Light ◽

Energy Fluctuation ◽

Hydrodynamic Analogy ◽

Non Local ◽

Minimum Uncertainty ◽

Quantum Hydrodynamic ◽

Transmission Speed

This work shows that in the frame of the stochastic generalization of the quantum hydrodynamic analogy (QHA) the uncertainty principle is fully compatible with the postulate of finite transmission speed of light and information. The theory shows that the measurement process performed in the large scale classical limit in presence of background noise, cannot have a duration smaller than the time need to the light to travel the distance up to which the quantum non-local interaction extend itself. The product of the minimum measuring time multiplied by the variance of energy fluctuation due to presence of stochastic noise shows to lead to the minimum uncertainty principle. The paper also shows that the uncertainty relations can be also derived if applied to the indetermination of position and momentum of a particle of mass m in a quantum fluctuating environment.

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QSAR Analysis for Antioxidant Activity of Dipicolinic Acid Derivatives

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180213092352 ◽

2018 ◽

Vol 21 (3) ◽

pp. 204-214 ◽

Cited By ~ 3

Author(s):

Vesna Rastija ◽

Maja Molnar ◽

Tena Siladi ◽

Vijay Hariram Masand

Keyword(s):

Antioxidant Activity ◽

Antioxidant Activities ◽

Dipicolinic Acid ◽

External Validation ◽

Qsar Model ◽

Internal Validation ◽

Qsar Analysis ◽

Dragon Descriptors ◽

Qsar Models ◽

New Compounds

Aims and Objectives: The aim of this study was to derive robust and reliable QSAR models for clarification and prediction of antioxidant activity of 43 heterocyclic and Schiff bases dipicolinic acid derivatives. According to the best obtained QSAR model, structures of new compounds with possible great activities should be proposed. Methods: Molecular descriptors were calculated by DRAGON and ADMEWORKS from optimized molecular structure and two algorithms were used for creating the training and test sets in both set of descriptors. Regression analysis and validation of models were performed using QSARINS. Results: The model with best internal validation result was obtained by DRAGON descriptors (MATS4m, EEig03d, BELm4, Mor10p), split by ranking method (R2 = 0.805; R2 ext = 0.833; F = 30.914). The model with best external validation result was obtained by ADMEWORKS descriptors (NDB, MATS5p, MDEN33, TPSA), split by random method (R2 = 0.692; R2 ext = 0.848; F = 16.818). Conclusion: Important structural requirements for great antioxidant activity are: low number of double bonds in molecules; absence of tertial nitrogen atoms; higher number of hydrogen bond donors; enhanced molecular polarity; and symmetrical moiety. Two new compounds with potentially great antioxidant activities were proposed.

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Sliding Contacts in Planetary Magnetospheres

Symmetry ◽

10.3390/sym13020283 ◽

2021 ◽

Vol 13 (2) ◽

pp. 283

Author(s):

Elena Belenkaya ◽

Igor Alexeev

Keyword(s):

Large Scale ◽

Strong Field ◽

Magnetized Plasma ◽

Sliding Contacts ◽

Radio Emissions ◽

Planetary Magnetospheres ◽

Current Task ◽

Surrounding Space ◽

Non Local ◽

A Current

In the planetary magnetospheres there are specific places connected with velocity breakdown, reconnection, and dynamo processes. Here we pay attention to sliding layers. Sliding layers are formed in the ionosphere, on separatrix surfaces, at the magnetopauses and boundaries of stellar astrospheres, and at the Alfvén radius in the equatorial magnetosphere of rapidly rotating strongly magnetized giant planets. Although sliding contacts usually occur in thin local layers, their influence on the global structure of the surrounding space is very great. Therefore, they are associated with non-local processes that play a key role on a large scale. There can be an exchange between different forms of energy, a generation of strong field-aligned currents and emissions, and an amplification of magnetic fields. Depending on the conditions in the magnetosphere of the planet/exoplanet and in the flow of magnetized plasma passing it, different numbers of sliding layers with different configurations appear. Some are associated with regions of auroras and possible radio emissions. The search for planetary radio emissions is a current task in the detection of exoplanets.

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Modification and Validation of the Phosphate Removal Model: A Multicenter Study

Kidney & Blood Pressure Research ◽

10.1159/000511375 ◽

2021 ◽

pp. 1-10

Author(s):

Weichen Zhang ◽

Qiuna Du ◽

Jing Xiao ◽

Zhaori Bi ◽

Chen Yu ◽

...

Keyword(s):

Polynomial Regression ◽

External Validation ◽

Original Model ◽

Phosphate Concentration ◽

Phosphate Removal ◽

Internal Validation ◽

Modified Model ◽

New Model ◽

Significant Difference ◽

Removal Model

Background: Our research group has previously reported a noninvasive model that estimates phosphate removal within a 4-h hemodialysis (HD) treatment. The aim of this study was to modify the original model and validate the accuracy of the new model of phosphate removal for HD and hemodiafiltration (HDF) treatment. Methods: A total of 109 HD patients from 3 HD centers were enrolled. The actual phosphate removal amount was calculated using the area under the dialysate phosphate concentration time curve. Model modification was executed using second-order multivariable polynomial regression analysis to obtain a new parameter for dialyzer phosphate clearance. Bias, precision, and accuracy were measured in the internal and external validation to determine the performance of the modified model. Results: Mean age of the enrolled patients was 63 ± 12 years, and 67 (61.5%) were male. Phosphate removal was 19.06 ± 8.12 mmol and 17.38 ± 6.75 mmol in 4-h HD and HDF treatments, respectively, with no significant difference. The modified phosphate removal model was expressed as Tpo4 = 80.3 × C45 − 0.024 × age + 0.07 × weight + β × clearance − 8.14 (β = 6.231 × 10−3 × clearance − 1.886 × 10−5 × clearance2 – 0.467), where C45 was the phosphate concentration in the spent dialysate measured at the 45th minute of HD and clearance was the phosphate clearance of the dialyzer. Internal validation indicated that the new model was superior to the original model with a significantly smaller bias and higher accuracy. External validation showed that R2, bias, and accuracy were not significantly different than those of internal validation. Conclusions: A new model was generated to quantify phosphate removal by 4-h HD and HDF with a dialyzer surface area of 1.3–1.8 m2. This modified model would contribute to the evaluation of phosphate balance and individualized therapy of hyperphosphatemia.

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How Does Administrative Data Compare with Census Data for the Measurement of Internal Migration? The Case of Northern Ireland, 2001–2011

Applied Spatial Analysis and Policy ◽

10.1007/s12061-020-09369-w ◽

2021 ◽

Author(s):

Brian Foley ◽

Tony Champion ◽

Ian Shuttleworth

Keyword(s):

Administrative Data ◽

Internal Migration ◽

Census Data ◽

Local Population ◽

Population Data ◽

Population Estimates ◽

Demographic Groups ◽

Small Areas ◽

Intercensal Period ◽

Statistical Agencies

AbstractThe paper compares and contrasts internal migration measured by healthcard-based administrative data with census figures. This is useful because the collection of population data, its processing, and its dissemination by statistical agencies is becoming more reliant on administrative data. Statistical agencies already use healthcard data to make migration estimates and are increasingly confident about local population estimates from administrative sources. This analysis goes further than this work as it assesses how far healthcard data can produce reliable data products of the kind to which academics are accustomed. It does this by examining migration events versus transitions over a full intercensal period; population flows into and out of small areas; and the extent to which it produces microdata on migration equivalent to that in the census. It is shown that for most demographic groups and places healthcard data is an adequate substitute for census-based migration counts, the exceptions being for student households and younger people. However, census-like information is still needed to provide covariates for analysis and this will still be required whatever the future of the traditional census.

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Mapping the Distribution of Water Resource Security in the Beijing-Tianjin-Hebei Region at the County Level under a Changing Context

Sustainability ◽

10.3390/su11226463 ◽

2019 ◽

Vol 11 (22) ◽

pp. 6463 ◽

Cited By ~ 1

Author(s):

Li ◽

Yin ◽

Zhang ◽

Croke ◽

Guo ◽

...

Keyword(s):

Climate Change ◽

Water Resources ◽

Water Resource ◽

Water Resource Management ◽

Large Scale ◽

Water Diversion ◽

County Level ◽

Populated Region ◽

Water Resource Security ◽

Resource Security

The Beijing-Tianjin-Hebei (Jingjinji) region is the most densely populated region in China and suffers from severe water resource shortage, with considerable water-related issues emerging under a changing context such as construction of water diversion projects (WDP), regional synergistic development, and climate change. To this end, this paper develops a framework to examine the water resource security for 200 counties in the Jingjinji region under these changes. Thus, county-level water resource security is assessed in terms of the long-term annual mean and selected typical years (i.e., dry, normal, and wet years), with and without the WDP, and under the current and projected future (i.e., regional synergistic development and climate change). The outcomes of such scenarios are assessed based on two water-crowding indicators, two use-to-availability indicators, and one composite indicator. Results indicate first that the water resources are distributed unevenly, relatively more abundant in the northeastern counties and extremely limited in the other counties. The water resources are very limited at the regional level, with the water availability per capita and per unit gross domestic product (GDP) being only 279/290 m3 and 46/18 m3 in the current and projected future scenarios, respectively, even when considering the WDP. Second, the population carrying capacity is currently the dominant influence, while economic development will be the controlling factor in the future for most middle and southern counties. This suggests that significant improvement in water-saving technologies, vigorous replacement of industries from high to low water consumption, as well as water from other supplies for large-scale applications are greatly needed. Third, the research identifies those counties most at risk to water scarcity and shows that most of them can be greatly relieved after supplementation by the planned WDP. Finally, more attention should be paid to the southern counties because their water resources are not only limited but also much more sensitive and vulnerable to climate change. This work should benefit water resource management and allocation decisions in the Jingjinji region, and the proposed assessment framework can be applied to other similar problems.

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Using Bus Ticketing Big Data to Investigate the Behaviors of the Population Flow of Chinese Suburban Residents in the Post-COVID-19 Phase

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18116066 ◽

2021 ◽

Vol 18 (11) ◽

pp. 6066

Author(s):

Yanbing Bai ◽

Lu Sun ◽

Haoyu Liu ◽

Chao Xie

Keyword(s):

Travel Behavior ◽

Large Scale ◽

Behavior Patterns ◽

Population Movements ◽

Economic Level ◽

Passenger Travel ◽

Scale Population ◽

Travel Behaviors ◽

Railway Passenger ◽

And Control

Large-scale population movements can turn local diseases into widespread epidemics. Grasping the characteristic of the population flow in the context of the COVID-19 is of great significance for providing information to epidemiology and formulating scientific and reasonable prevention and control policies. Especially in the post-COVID-19 phase, it is essential to maintain the achievement of the fight against the epidemic. Previous research focuses on flight and railway passenger travel behavior and patterns, but China also has numerous suburban residents with a not-high economic level; investigating their travel behaviors is significant for national stability. However, estimating the impacts of the COVID-19 for suburban residents’ travel behaviors remains challenging because of lacking apposite data. Here we submit bus ticketing data including approximately 26,000,000 records from April 2020–August 2020 for 2705 stations. Our results indicate that Suburban residents in Chinese Southern regions are more likely to travel by bus, and travel frequency is higher. Associated with the economic level, we find that residents in the economically developed region more likely to travel or carry out various social activities. Considering from the perspective of the traveling crowd, we find that men and young people are easier to travel by bus; however, they are exactly the main workforce. The indication of our findings is that suburban residents’ travel behavior is affected profoundly by economy and consistent with the inherent behavior patterns before the COVID-19 outbreak. We use typical regions as verification and it is indeed the case.

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