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AbstractWe study the modeling and forecasting of high-dimensional functional time series (HDFTS), which can be cross-sectionally correlated and temporally dependent. We introduce a decomposition of the HDFTS into two distinct components: a deterministic component and a residual component that varies over time. The decomposition is derived through the estimation of two-way functional analysis of variance. A functional time series forecasting method, based on functional principal component analysis, is implemented to produce forecasts for the residual component. By combining the forecasts of the residual component with the deterministic component, we obtain forecast curves for multiple populations. We apply the model to age- and sex-specific mortality rates in the United States, France, and Japan, in which there are 51 states, 95 departments, and 47 prefectures, respectively. The proposed method is capable of delivering more accurate point and interval forecasts in forecasting multi-population mortality than several benchmark methods considered. [ABSTRACT FROM AUTHOR]

In Colombia the agricultural sector has difficulties in the integration of technologies, due to the difficulties of the topography, very characteristic in the area of Colombian mountain ranges that pass through the main agricultural departments of the country and the limitations of human capacity; the citrus harvesting process has traditionally been done by hand, employing thousands of people who do not achieve significant yields;, thus causing an increase in production costs with an impact on harvest indicators, measured in terms of quality and productivity. This study aims to determine the impact of field slope conditions on quality indicators and indicators of effectiveness, efficiency, and loss indictors, used to evaluate the productivity of the orange harvesting process in a case study in the Department of Caldas-Colombia in order to identify opportunities for process improvement. Field information was made on orangeproducing farms with different land slopes classified into four categories. Statistically significant partnerships were identified between the efficiency, efficiency and loss indicators and the field slope conditions. In addition, some of these indicators showed inverse relationships to the slope gradient. On the contrary, the quality of the fruit is not affected by the slope conditions of the land. [ABSTRACT FROM AUTHOR]

Background Antibody (Ab) tests for SARS-CoV-2 virus allows for the estimation of incidence, level of exposure and duration of immunity acquired by a previous infection. In health workers, the hospital setting might convey a greater risk of infection. Aims To describe the frequency of immunoglobulin G (IgG) Abs (IgG-Abs) to the SARS-CoV-2 virus among workers at a third-level university hospital in Colombia. Methods In this cross-sectional study, we included medical and non-medical personnel with at least one real-time polymerase chain reaction (RT–PCR)/antigen test between March 2020 and March 2021. In April 2021, an IgG-Ab test against SARS-CoV-2 was conducted for all participants and replicated 2 weeks later in a random sample (10%). The frequency of IgG-Abs is presented based on status (positive/negative) and time elapsed since RT–PCR/antigen test (<3 months, 3–6 months, >6 months). Results We included 1021 workers (80% women, median age 34 years (interquartile range 28–42), 73% medical personnel, 23% with previous positive RT–PCR/antigen). The overall seroprevalence was 35% (95% CI 31.6–37.4, 35% in medical and 33% in non-medical personnel). For those with a previous positive RT–PCR/antigen test, the seroprevalence was 90% (<3 months), 82% (3–6 months) and 48% (>6 months). In participants with a previous negative RT–PCR/antigen test, the seroprevalence was 17% (<3 months), 21% (3–6 months) and 29% (>6 months). Conclusions High IgG-Ab positivity was found in hospital personnel, regardless of work activities. The prevalence of detectable Abs differed by previous RT–PCR/antigen status and time elapsed since the diagnostic test. [ABSTRACT FROM AUTHOR]