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—The results of geomagnetic studies in the Tashkent and Fergana geodynamic test sites, Uzbekistan, are presented. Detail analysis of anomalous geomagnetic variations caused by the processes occurring at different depths in the Earth’s crust and upper mantle is conducted. By their linear size, variations are divided into regional (100 km and larger) and local (1 to 5 km and larger). Regional anomalous variations manifest themselves by sinusoidal, bay-like, and trend forms and last one to seven years. In the trend-type variations, the gradient is 0.5–2.0 nT/yr. Local anomalous variations typically have sinusoidal and bay-like shape. Bay anomalies have both positive and negative sign, and the change is reversible. The intensity of the anomalies ranges from 2 to 25 nT and the duration is from 10–15 days to three years or even longer. The local anomalous variations are neither precursory nor technogenic. Numerous anomalies of this type were for the first time revealed at the geodynamic test sites in Uzbekistan. The analysis of the data for the past 40–50 years has shown the absence of information on this type of anomalous variations. They can neither be explained by conventional mechanisms responsible for secular behavior of the geomagnetic field, nor by lithologic composition of the rocks, tectonics fetures, hydrogeological conditions, and geophysical fields of the studied territories. One of the peculiarities of local anomalous variations of this type is that they can change in time, in shape, in size of the area, in intensity, and in sign. The published data relevant to the anomalies in the secular variation of the geomagnetic field have been analyzed. However, unfortunately, these data provide almost no information on the origin of local anomalous variations discussed in our work.

Objective:Our objective is to forecast the number of coronavirus disease 2019 (COVID-19) cases in the state of Maryland, United States, using transfer function time series (TS) models based on a Social Distancing Index (SDI) and determine how their parameters relate to the pandemic mechanics.Methods:A moving window of 2 mo was used to train the transfer function TS model that was then tested on the next week data. After accounting for a secular trend and weekly cycle of the SDI, a high correlation was documented between it and the daily caseload 9 days later. Similar patterns were also observed on the daily COVID-19 cases and incorporated in our models.Results:In most cases, the proposed models provide a reasonable performance that was, on average, moderately better than that delivered by TS models based only on previous observations. The model coefficients associated with the SDI were statistically significant for most of the training/test sets.Conclusions:Our proposed models that incorporate SDI can forecast the number of COVID-19 cases in a region. Their parameters have real-life interpretations and, hence, can help understand the inner workings of the epidemic. The methods detailed here can help local health governments and other agencies adjust their response to the epidemic.

Low physical fitness has been found to be associated with many chronic diseases and medical conditions. Knowledge of secular trends in physical fitness is important to initiate countermeasures for addressing negative trends. The aim of this study was to analyze secular trends in health-related muscular fitness in Slovenian children and adolescents between 1983 and 2014. Data were collected as part of "The Analysis of Children's Development in Slovenia (ACDSi)" study in 1983, 1993/94, 2003/04, and 2013/14. Anthropometry (body weight, height, BMI, and triceps skinfold) and muscular fitness (standing long jump, bent-arm hang, and sit-ups 60 s test) of 18730 (9168 female) students from primary and secondary schools were recorded. The secular trend was analyzed considering anthropometry. The results showed that anthropometric measures had an increasing trend and overall muscular fitness had a decreasing trend. Leg muscle power decreased over the decades in all age groups (relative difference between -1.5% and -2.6%), being more pronounced in boys. Arm muscle strength decreased in two younger age groups (range -21.1% to -42.7%, 6-10, and 11-14 years), but not in the oldest group (15-19 years), where the increase occurred in both genders (0.4% to 9.3%). In terms of decades, the largest negative changes (-30.1%) occurred from 1993/94 to 2003/04 and the smallest changes (-4.2%) from 2003/04 to 2013/14. The overall trend in repetitive core strength surprisingly increased (1.1% to 18.3%). There is a need to promote healthy lifestyles, raise parental awareness and use all government resources to redirect the negative trend in physical fitness.

Introduction: Health of the residents of the territories adjacent to the space launches have been shown to be inferior to the national average. However, the data from the Altai region are scarce. Aim: To assess health status of the residents of the territories of the Altai region adjacent to the areas of falling of separating parts of launch vehicles Methods: All residents of the affected territories were examined by medical teams in 1999 (n = 1 929), 2005 (n = 1 213), 2010 (n = 1 016) and 2015 (n = 843). Overall prevalence rates class-specific rates per 1000 population were calculated. Secular trends were analyzed and comparisons with the reference population were performed. Results: The overall prevalence decreased from 4 400,5 - 4 406,5 % in 1999 to 3 932,7 - 3 941,5 % in 2015 (p < 0.001) with no clear trend. In 1999, the main contributors to the overall burden of diseases were diseases of the endocrine system (1 072,2 - 1 075,0 %), diseases of the circulatory system (526,9 - 572,1 %), diseases of the eye and its appendages (390,8 - 435,6 %), and diseases of the respiratory system - 318,0 - 361,2 %. In 2015, the most prevalent illnesses were diseases of the circulatory system (743,4 - 801,0 %), diseases of the respiratory system (668,3 - 731,5 %), diseases of the endocrine system (636,6 - 701,4 %), and diseases of the eye and its appendages (452,0 - 520,8 %). Residents of the study group had greater overall prevalence of diseases (3 932,7 - 3,941,5 %) than the reference (2 539,3 - 2,539,5 %), p < 0.001. The same was observed for the most classes of diseases. Conclusions: The overall prevalence of diseases among the residents of the territories adjacent to the areas of falling of separating parts of launch vehicles significantly decreased from 2015 to 1999 with no obvious linear trend. Women had poorer health than men. The overall prevalence of diseases and the prevalence of the most classes of diseases in the study group is significantly higher than in the reference population.

Introduction: Monitoring the consumption profile of medicines has become one of the important tools for assessing the rationality as it depends on the various indigenous factors. ICMR-NIN monitors drug consumption at retail pharmacy outlets with an objective to document the precepts and practices exist between prescription and consumption of medicine. This facilitates to translate in developing interventions and policy strategies for promotion of rational use of drugs.

The purpose of the present study was to analyze the secular trends in anthropometric characteristics and health-related physical fitness (i.e., flexibility, muscular strength and speed/agility) in Macedonian children between 2012 and 2019. Materials and methods. We analyzed the secular trends in anthropometric characteristics and health-related physical fitness in Macedonian children between 2012 and 2019. Two representative population studies were conducted 7 years apart in children (6-10 years) from Skopje (Mаcedonia). Both studies used the same anthropometric measures and tests to assess physical fitness: height, weight, body mass index, body fat percentage, muscle mass percentage, sit and reach, handgrip strength, standing long jump, 30 sec sit ups, and 4 × 10 m shuttle run. Result. The boys and girls measured in 2019 had significantly better performance in the sit and reach (Cohen’s d ~0.4 and ~0.5, respectively), 30 sec sit ups (Cohen’s d ~0.3 and ~0.2, respectively), and 4 × 10 m shuttle run (Cohen’s d ~0.7 and ~0.8, respectively) tests compared to those measured in 2012–2013. Levels of the standing long jump were significantly lower in 2019 in boys and girls (Cohen’s d ~0.6 for both). Conclusions. Based on the results of the study, it can be concluded that Macedonian children measured in 2019 have higher levels of flexibility, abdominal muscle strength and coordination, speed and agility, but lower levels of explosive force of the lower limbs than their counterparts measured. 7 years ago, no statistically significant differences were found in anthropometric measures and measures of body weight.

Aims To investigate secular trends in severe periodontitis incidence, prevalence and disability-adjusted life year (DALY) rates in China, India, Japan, South Korea and Thailand from 1990 to 2017. Materials and methods Data were obtained from the "Global Burden of Disease Study" 2017. The annual percentage change and average annual percentage change were calculated using Joinpoint regression analysis. The independent age, period and cohort effects were estimated by age-period-cohort analysis. Results From 1990 to 2017, the overall age-standardized incidence, prevalence and DALY rates increased in China, Japan and India, while decreasing in South Korea and Thailand. The highest incidence, prevalence and DALY rates were in India. By APC analysis, the age effect presented increase in 20-59 years in China, Japan and South Korea, 20-54 years in India and 20-64 years in Thailand; the period effect showed progressive increases in five countries, with the most significant increase shown in China; the cohort effect showed monotonic decreases with birth cohort in five countries. Conclusions Severe periodontitis poses a serious burden in Asian countries, especially China and India. We suggest raising people's awareness of periodontal health and providing professional interventions in these countries, especially for high-risk groups, such as younger people aged ≤65 years.

Summary In this study, we found that regional disparity in incidence of hip fractures has converged. Also, annual hip fracture risk ratios between genders have systematically diminished over time. Introduction Several studies have reported secular trends in hip fracture incidence, but knowledge about the possible causes is limited. We studied potential explanations by examining spatio-temporal epidemiology of the fractures and estimating relative risks between genders. Methods This observational study was based on all inpatient hospital discharges in 1972–2018 in Finland. We divided the data by gender, 5-year age groups and Finnish sub-regions and estimated gender and age standardized spatio-temporal rates of hip fractures by using a Bayesian age-period-cohort model. Results In 1972, women’s hip fracture incidence was 1.2–1.3 times higher in western and coastal Finland compared to eastern and inland areas. Also, women had approximately 1.7 times higher average risk to get a hip fracture compared to men. Today, the hip fracture differences between the areas have converged to insignificant and the relative risk between genders has diminished to 1.2. Age-specific relative risks indicate greater hip fracture risk for younger men and older women, and the women’s risk increases beyond the risk of men at age 65 which is ten years later than in the beginning of the study period. Conclusion Incidence of hip fracture has converged significantly between regions and genders. Especially factors related with socioeconomic development and increased frailty and longevity seem to be important. The hip fracture incidence rate ratio between women and men has systematically decreased in time, and more attention should be paid to hip fracture risk in men in the future. Supplementary Information The online version contains supplementary material available at 10.1007/s00198-021-05906-6.

Since the early 1980s, the composition of US public firms has progressively shifted toward less profitable firms with high growth potential (Fama and French, 2004). We estimate a dynamic corporate finance model to quantify the role of this selection mechanism for the secular trend in cash holdings among US public firms. We find that an increase in the precautionary savings motive—primarily driven by the decline in initial profitability among R&D-intensive new lists—explains about 50% of the upward trend in cash holdings. This selection mechanism also explains part of the upward trend in sales growth volatility.

Pubertal BMI change is an independent risk marker of cardiovascular mortality/morbidity. Previous studies demonstrated a secular trend of increased childhood BMI but it is unknown if there is a concomitant secular trend regarding pubertal BMI change. The aim of this study was to describe the trend in pubertal BMI change. We collected heights and weights before and after puberty from school health records and military conscript records for boys born every five years during 1946–1991 (n = 3650, total cohort) and calculated pubertal BMI change (young adult BMI at 20 years of age minus childhood BMI at 8 years of age) for all study participants. A secular trend of increasing pubertal BMI change during the study period was observed. The increase in pubertal BMI change (0.27 kg/m2 per decade [0.22; 0.32]) explained 54% of the secular trend of increasing young adult BMI (0.50 kg/m2 per decade [0.43; 0.57]). We made the novel observation that there is a secular trend of increasing pubertal BMI change. We propose that the secular trend of increasing pubertal BMI change might contribute more than the secular trend of increasing childhood BMI to the adverse cardiovascular health consequences associated with the ongoing obesity epidemic.

Objectives: This study analyzed secular trends in sex ratio at birth in Korea by birth order using birth records from Statistics Korea between 1981 and 2017. Methods: A total of 21,685,402 birth records were used and the sex ratio was measured as the number of males per 100 females. Sex order was categorized into the first, second, and third and higher. Births of unclassified sex order (n=47,445) were excluded from the analysis. We conducted logistic regression analyses to test if there are significant changes in sex ratio at birth for all other periods, using the period 1981-1984 as the reference group, and to test if there are significant changes for the higher order births, using the first order births as the reference group. Odds ratio and 95% confidence interval were calculated for each period. Results: Since having peaked at 116.5 in 1990, the ratio for total births gradually declined to reach the lowest point of 105.0 in 2016. The sex ratio increased with rising birth order. A baby born for the second and the third and higher birth order was 1.07 (95% confidence interval, 95% CI: 1.06-1.08) and 1.86 (95% CI: 1.85-1.88), respectively, times more likely to be male than a first-born baby for period 1990-1994. Conclusions: Having peaked at 209.7 in 1993, the sex ratio for the third and higher order births reverted to the naturally occurring level of 105.5 in 2015. Despite the return, the abnormally high sex ratio for the third and higher order births persisted until the early 2010s.

The International Geomagnetic Reference Field (IGRF) is a set of parameters representing the large-scale internal part of Earth’s magnetic field. The 13th generation IGRF requested candidate models for a definitive main field for 2015.0, a provisional main field for 2020.0, and a predictive secular variation covering the period 2020.0–2025.0. The University of Colorado (CU) and the National Centers for Environmental Information (NCEI), part of the National Oceanic and Atmospheric Administration (NOAA), have produced these three candidate models for consideration in IGRF-13. In this paper, we present the methodology used to derive our candidate models. Our candidates were built primarily from Swarm satellite data, and also relied on geomagnetic indices derived from the ground observatory network. The ground observatories played a crucial role as independent data in validating our candidates. This paper also provides a retrospective assessment of the CU/NCEI candidate model to the previous IGRF (IGRF-12) and discusses the impact of differences between candidate and final IGRF models on global model errors.

We present geomagnetic main field and secular variation time series, at 300 equal-area distributed locations and at 490 km altitude, derived from magnetic field measurements collected by the three Swarm satellites. These Geomagnetic Virtual Observatory (GVO) series provide a convenient means to globally monitor and analyze long-term variations of the geomagnetic field from low-Earth orbit. The series are obtained by robust fits of local Cartesian potential field models to along-track and East–West sums and differences of Swarm satellite data collected within a radius of 700 km of the GVO locations during either 1-monthly or 4-monthly time windows. We describe two GVO data products: (1) ‘Observed Field’ GVO time series, where all observed sources contribute to the estimated values, without any data selection or correction, and (2) ‘Core Field’ GVO time series, where additional data selection is carried out, then de-noising schemes and epoch-by-epoch spherical harmonic analysis are applied to reduce contamination by magnetospheric and ionospheric signals. Secular variation series are provided as annual differences of the Core Field GVOs. We present examples of the resulting Swarm GVO series, assessing their quality through comparisons with ground observatories and geomagnetic field models. In benchmark comparisons with six high-quality mid-to-low latitude ground observatories we find the secular variation of the Core Field GVO field intensities, calculated using annual differences, agrees to an rms of 1.8 nT/yr and 1.2 nT/yr for the 1-monthly and 4-monthly versions, respectively. Regular sampling in space and time, and the availability of data error estimates, makes the GVO series well suited for users wishing to perform data assimilation studies of core dynamics, or to study long-period magnetospheric and ionospheric signals and their induced counterparts. The Swarm GVO time series will be regularly updated, approximately every four months, allowing ready access to the latest secular variation data from the Swarm satellites.

The three candidate models submitted by the British Geological Survey for the 13th generation International Geomagnetic Reference Field are described. These DGRF and IGRF models are derived from vector and scalar magnetic field data from the European Space Agency Swarm satellites and ground observatories, covering the period 2013.9 to 2019.7. The internal field model has time dependence for degrees 1 to 15, represented by order 6 B-splines with knots at six monthly intervals. We also solve for a degree 1 external field time dependence describing annual and semi-annual signals with additional dependence on a bespoke Vector Magnetic Disturbance index. Satellite data are weighted by spatial density, along-track standard deviations, and a larger-scale noise estimator defined in terms of a measure of Local Area Vector Activity at the geographically closest magnetic observatories to the sampled datum. Forecasting of the magnetic field secular variation for 2020–2025 is by advection of the main field using steady core surface flows with steady acceleration applied. We also investigate the performance of the previous generation of candidate secular variation models, for IGRF-12, analysing the agreement of the candidates between 2015 and 2020 with the retrospective IGRF-13. We find that there is no clear distinction between the performance of mathematically and physically extrapolated forecasts in the period 2015–2020. We confirm that the methodology for the BGS IGRF-12 predictions performed well, despite observed secular accelerations that are highlighted by our analysis, and thus justify the methodology used for our IGRF-13 SV candidate.

Background Smoking, obesity and alcohol abuse greatly affect mortality and exhibit a distinct time dynamic, with their prevalence and associated mortality rates increasing and (eventually) declining over time. Their combined impact on secular trends in life expectancy is unknown but is relevant for understanding these trends. We therefore estimate the combined impact of smoking, obesity and alcohol on life-expectancy trends in Europe. Methods We used estimated national age-specific smoking-, obesity- and alcohol-attributable mortality fractions for 30 European countries by sex, 1990–2014, which we aggregated multiplicatively to obtain lifestyle-attributable mortality. We estimated potential gains in life expectancy by eliminating lifestyle-attributable mortality and compared past trends in life expectancy at birth (e0) with and without lifestyle-attributable mortality. We examined all countries combined, by region and individually. Results Among men, the combined impact of smoking, obesity and alcohol on e0 declined from 6.6 years in 1990 to 5.8 years in 2014, mainly due to declining smoking-attributable mortality. Among women, the combined impact increased from 1.9 to 2.3 years due to mortality increases in all three lifestyle-related factors. The observed increase in e0 over the 1990–2014 period was 5.0 years for men and 4.0 years for women. After excluding lifestyle-attributable mortality, this increase would have been 4.2–4.3 years for both men and women. Conclusion Without the combined impact of smoking, obesity and alcohol, the increase over time in life expectancy at birth would have been smaller among men but larger among women, resulting in a stable increase in e0, parallel for men and women.

The atmospheric water holding capacity will increase with temperature according to Clausius-Clapeyron scaling and affects precipitation. The rates of change in future precipitation extremes are quantified with changes in surface air temperature. Precipitation extremes in China are determined for the 21st century in six simulations using a regional climate model, RegCM4, and 17 global climate models that participated in CMIP5. First, we assess the performance of the CMIP5 models and RCM runs in their simulation of extreme precipitation for the current period (RF: 1982–2001). The CMIP5 models and RCM results can capture the spatial variations of precipitation extremes, as well as those based on observations: OBS and XPP. Precipitation extremes over four subregions in China are predicted to increase in the mid-future (MF: 2039–58) and far-future (FF: 2079–98) relative to those for the RF period based on both the CMIP5 ensemble mean and RCM ensemble mean. The secular trends in the extremes of the CMIP5 models are predicted to increase from 2008 to 2058, and the RCM results show higher interannual variability relative to that of the CMIP5 models. Then, we quantify the increasing rates of change in precipitation extremes in the MF and FF periods in the subregions of China with the changes in surface air temperature. Finally, based on the water vapor equation, changes in precipitation extremes in China for the MF and FF periods are found to correlate positively with changes in the atmospheric vertical wind multiplied by changes in surface specific humidity (significant at the p < 0.1 level).

Responses of atmospheric carbon dioxide (CO2) density to geomagnetic secular variation are investigated using the Whole Atmosphere Community Climate Model-eXtended (WACCM-X). Our ensemble simulations show that CO2 volume mixing ratios (VMRs) increase at high latitudes and decrease at mid and low latitudes by several ppmv in response to a 50% weakening of the geomagnetic field. Statistically significant changes in CO2 are mainly found above ~90 km altitude and primarily redetermine the energy budget at ~100–110 km. Our analysis of transformed Eulerian mean (TEM) circulation found that CO2 change is caused by enhanced upwelling at high latitudes and downwelling at mid and low latitudes as a result of increased Joule heating. We further analyzed the atmospheric CO2 response to realistic geomagnetic weakening between 1978 and 2013, and found increasing (decreasing) CO2 VMRs at high latitudes (mid and low latitudes) accordingly. For the first time, our simulation results demonstrate that the impact of geomagnetic variation on atmospheric CO2 distribution is noticeable on a time scale of decades.

Introduction: Despite changes in prenatal diagnostic methods and perceptions regarding the prognosis of and treatment options for patients with trisomy 18 syndrome, data on the secular changes in patient survival are limited. This study aimed to investigate the survival pattern for such patients. Methods: To investigate the general patient survival patterns, we used data from the vital statistics database of deaths in Japan from 1975 to 2016. We described demographic factors, such as sex, gestational age at delivery, and surgical history, for patients whose primary cause of death was trisomy 18 syndrome. Results: The proportions of deaths within 24 h of birth (4.0% in 1975–1980 to 21.9% in 2011–2016) and at age ≥1 year (8.9% in 1975–1980 to 17.7% in 2011–2016) increased. The median survival time was higher for females, infants born after 37 weeks of gestation, and those who received surgical intervention. The median survival time tripled among patients who received surgical intervention (61.5 days in 1995–2005 to 182.5 days in 2006–2016), and the proportion of such patients increased (from 3.8% in 1995 to 24.1% of the entire affected population in 2016). Discussion/Conclusion: In Japan, the median survival time of infants with trisomy 18 increased over time, and the proportion of death within 24 h and at ≥1 year increased. Greater acknowledgement of the possible benefits of surgical intervention likely led to the increased provision of interventions and contributed to the increased survival time.

Introduction: Secular changes in hip fracture incidence have been reported in the last few decades in Japan, but whether long-term bone mineral density (BMD) is also changing is unclear. This study aimed to determine whether BMD of Japanese women has changed over time. Methods: Subjects were 10,649 adult women who underwent BMD measurement in a health check-up population in Niigata, Japan, between 1995 and 2013. BMD of the distal, non-dominant forearm was measured by dual-energy X-ray absorptiometry. Demographic information and BMI were also obtained. Secular trends were determined by linear regression analysis. Results: BMD of subjects in their 40’s decreased significantly in the age-adjusted model (P for trend=0.0162), but not in the age- and BMI-adjusted model (P for trend=0.2171). BMD of subjects in their 50’s decreased marginally in the age-adjusted model (P for trend=0.0535), but not in the age- and BMI-adjusted model (P for trend=0.6601). BMDs of subjects in their 30’s and 60’s did not significantly change, while BMIs of subjects in their 40’s-60’s decreased significantly. Conclusions: A secular decrease in BMD, partly attributed to decreases in BMI, was observed in middle-aged Japanese women from 1995 to 2013. Measures to help maintain suitable BMI will be necessary to prevent a decrease in BMD among women.

Background: Various studies have indicated that the prognosis of leukemia has been improved in recent years, but the secular trends of incidence and long-term survival of all leukemia have not been thoroughly examined. Methods: We estimated the leukemia incidence and 5-year survival rate along with the temporal trends by sex, race, age, and subtype in the United States over the past four decades using Surveillance, Epidemiology, and End Results (SEER) database. Results: The overall incidence of leukemia steadily increased from 12.39/100 000 in 1975 to 14.65/100 000 in 2011, and then began to decline in recent years (13.73/100 000 in 2017), with average annual percent changes (APC) of 0.350 (P

Background Life expectancy in Japan has increased dramatically and is one of the longest in the world. However, the changes in lifespan in Japanese individuals with congenital diseases remain unknown. We investigated secular changes in the lifespan of people with Down syndrome over the last 20 years. Methods We observed secular trends in the number of stillbirths, deaths and the mortality rates at ages 20, 40, and 60 among all deaths registered with Down syndrome as the cause of death (ICD10 code: Q90) in the Japan national death registry database between 1995 and 2016. Changes in the median age at death between 1995-2005 and 2006-2016 were investigated based on sex and history of surgery. Results We identified 240 stillbirths and 1,099 deaths in this period. The annual number of stillbirths and deaths above the age of 1 year increased, whereas the number of deaths below 1 year did not change. The proportional mortality indicator at ages 20, 40, and 60 increased from 21.7%, 11.7%, and 1.7% in 1995 to 69.9%, 66.7%, and 36.6% in 2016, respectively. The median age at death was higher in females, individuals without a surgical history, and deaths occurring in 2006-2016. The median age at death increased over the period in those without a surgical history. Conclusions The age at death among people with Down syndrome has increased over the last 20 years, with currently 1 in 3 persons living over 60 years, necessitating adequate social welfare services in this aging population.

The high level of noise is a special feature of the geomagnetic field on the territory of Slovenia. The tension of the Adriatic tectonic microplate, on which Slovenia entirely lies, was recognized as one of its sources. The interior of the Earth is also the source of geomagnetic jerks. They are impulses in the secular variation calculated on the basis of monthly or annual mean values of variation of the geomagnetic field. The paper presents an analysis of accelerations in a local magnetic field calculated on the bases of daily mean values of the magnetic field measured at PIA geomagnetic Observatory (Piran, Slovenia) in 2020. These accelerations indicate geomagnetic impulses at the regional level over days or weeks. Then these results are compared with the registered seismic activity in the West Balkans.

Objectives The prevalence of general overweight and obesity defined by body mass index criteria has greatly increased in Chinese children and adolescents in recent decades. However, few studies have considered the trend in abdominal obesity in Chinese children and adolescents. This study aimed to examine the secular trends in waist circumference (WC), waist-to-height ratio (WHtR) and the prevalence of abdominal obesity among Chinese children and adolescents aged 6–17 years from 1993 to 2015. Methods A total of 11,985 children and adolescents aged 6–17 years participated in the China Health and Nutrition Survey, a continuous cross-sectional survey, conducted from 1993 to 2015. Abdominal obesity was defined as WC≥age- and sex-specific 90th percentile based on the reference from Chinese children and adolescents or WHtR≥0.50. Results After adjustment for age, sex and region, mean WC increased from 60.27 cm in 1993 to 64.31 cm in 2015 (p for trend Conclusions The prevalence of abdominal obesity among Chinese children and adolescents aged 6–17 years has increased between 1993 and 2015.

Aim: We aimed to examine the distribution and secular changes of conscript body height in the geographic network of Norway since 1878 and to study its association with the degree of urbanization, and population density. Material and methods: Data on body height of Norwegian military conscripts were provided by the Statistics Norway Department (SSB). The sample comprised eight cohorts with the following measurement years: 1st 1877, 1878 and 1880, 2nd 1895-1897, 3rd 1915-1917, 4th 1935-1937, 5th 1955-1957, 6th 1975-1977, 7th 1995-1997, and 8th 2009-2011. For determining neighborhood correlations, a network was created consisting of neighboring counties, sharing a common border. Results: Average body height of Norwegian men increased by 10.9 cm between 1878 and 2010, but this trend was heterogeneous. Some counties increased by more than 1 cm per decade (Finmark) others by only 7 mm per decade (Sor-Trondelag). Urban counties and counties with higher population density showed stronger height trends than rural counties. The largest spread in body height between the various counties was observed in 1936 when for the first time people living in the more urban counties got taller than rural people. The height advantage of urban counties however, disappeared after 1996. At this time, also the secular trend in height had come to a halt. The secular trend in height had become obvious after the dissolution of the union between Norway and Sweden in 1905 and World War I, and was strongest between 1936 and 1956. During this period maximum between-county heterogeneity in height existed with body height differences of more than 6 cm between the tallest and the shortest county. The end of this period was characterized by social democratic reforms that flattened the income distribution, eliminated poverty, and ensured social services after World War II. Conclusion: The temporal coincidence between the trends in height, the degree of urbanization and the onset of the political transition of Norway from a Swedish province into an independent democratic wealthy modern European state after World War I and particularly after World War II, and the abatement of this trend after this period of transition had stabilized, suggest social and political components interfering with the regulation of physical growth in humans.