Vitamin D belongs to the group of liposoluble steroids mainly involved in bone metabolism by modulating calcium and phosphorus absorption or reabsorption at various levels, as well as parathyroid hormone production. Recent evidence has shown the extra-bone effects of vitamin D, including glucose homeostasis, cardiovascular protection, and anti-inflammatory and antiproliferative effects. This narrative review provides an overall view of vitamin D’s role in different settings, with a special focus on chronic kidney disease and kidney transplant.
Satellite data from the Climate Change Initiative (CCI) lakes project were used to examine the influence of climate on chlorophyll-a (Chl-a). Nonparametric multiplicative regression and machine learning were used to explain Chl-a concentration trend and dynamics. The main parameters of importance were seasonality, interannual variation, lake level, water temperature, the North Atlantic Oscillation, and antecedent rainfall. No evidence was found for an earlier onset of the summer phytoplankton bloom related to the earlier onset of warmer temperatures. Instead, a curvilinear relationship between Chl-a and the temperature length of season above 20°C (LOS) was found with longer periods of warmer temperature leading to blooms of shorter duration. We suggest that a longer period of warmer temperatures in the summer may result in earlier uptake of nutrients or increased calcite precipitation resulting in a shortening of the duration of phytoplankton blooms. The current scenario of increasing LOS of temperature with climate change may lead to an alteration of phytoplankton phenological cycles resulting in blooms of shorter duration in lakes where nutrients become limiting. Satellite-derived information on lake temperature and Chl-a concentration proved essential in detecting trends at appropriate resolution over time.
Perfluorinated compounds (PFCs) are a wide class of emerging pollutants. In this study, we applied the US EPA method 533 for the determination of 21 PFCs in river water samples. In particular, this method was used to investigate the presence of the target PFCs in six rivers in central Italy during a 4-month-long monitoring campaign. In 73% of the analyzed samples, at least some of the target PFCs were detected at concentrations higher than the limit of detection (LOD). The sum of the 21 target analytes (∑21PFCs) ranged from 4.3 to 68.5 ng L−1, with the highest concentrations measured in the month of June, probably due to a minor river streamflow occurring in the warmer summer months. Considering the individual congeners, PFBA and PFPeA, followed by PFHxA and PFOA, were the predominantly detected compounds. Short- and medium-chain PFCs (C4–C9) prevail over the long-chain PFCs (C10–C18), likely due to the increased industrial use and the higher solubility of short-chain PFCs compared to long-chain PFCs. The ecological risk assessment, conducted by using the risk quotient method, highlighted that the risk for aquatic environments associated with PFBA, PFPeA, PFBS, PFHxA and PFOA was low or negligible. Only for PFOA, there was a medium level of risk in two rivers in the month of June. With regard to PFOS, 54% of the river water samples were classified as “high risk” for the aquatic environment. The remaining 46% of the samples were classified as “medium risk.”
<p class="PlainText1">In compliance with the European and Italian regulations, the Environmental Protection Agency of Umbria Region (ARPA Umbria) defined specific river monitoring programs and networks based on river type definition, human pressures and risk analysis. The Umbria Region lies in Central Italy and it can be split into three hydro-ecoregions belonging to the Mediterranean area. Data on diatom community composition were collected in five different Mediterranean macrotypes (M1-M5) throughout the diatom-based river monitoring network that is composed by 52 sampling stations in 36 watercourses. The main aim of this study was to characterise and to analyse diatom diversity across the different regional river macrotypes. Specifically, we investigated if: i) there were differences in species diversity (species richness and Shannon Index) among macrotypes; ii) there was difference in three water quality indexes (ICMi, IPS, and TI) among sites; and iii) there was a relationship between the observed ICMi, IPS and TI value and the diatom diversity. Two-hundred diatom species and varieties were identified, and the number of species <em>per</em> sampling station ranged from a minimum of 10 to a maximum of 38 species. The most frequent and abundant species were <em>Amphora pediculus</em>, <em>Achnanthidium minutissimum,</em> <em>Navicula cryptotenella</em>, <em>Nitzschia dissipata</em>, and each macrotype showed some peculiar species. The ecological status evaluation based on Intercalibration Common Metric Index (ICMi) classified 69% of the water bodies in high or good class. Significant differences in diversity and ICMi value among stream macrotypes were found, with M4 (small and medium mountain) and M5 (small, lowland, temporary) typologies showing the lowest species richness, and with M5 showing the lowest Shannon Index. Conversely, M2 (small and medium lowland) and M5 showed the highest ICMi value. Lastly, significant correlations between Shannon Index and the ICMi, IPS and TI indexes were found.</p>
Perfluorinated compounds (PFCs) are a wide class of emerging pollutants still under study. In this work, we developed and validate a sensitive analytical method based on HPLC-MS/MS for the determination of 21 PFCs. This method was then used to investigate the presence of the target PFCs in six rivers in central Italy during a 4-months long monitoring campaign. 73% of the analytical determinations resulted higher than the limit of detection (LOD). The ∑21PFCs ranged from 4.3 to 68.5 ng L− 1 with the highest concentrations measured in June month, due to a minor river streamflow occurring in the warm periods. Between the individual congeners, PFBA and PFPeA, followed by PFHxA and PFOA were the predominant congeners detected. The evidence that short and medium chain PFCs (C4-C9) prevail over the long chain PFCs (C10-C18) could be attributed to the increased use and higher solubility of short chain PFCs compared to long chain PFCs. The ecological risk assessment, conducted by using risk quotient (RQ) method, highlighted that for PFBA, PFPeA, PFBS, PFHxA and PFOA the risk for aquatic environments was low or negligible. Only for PFOA there was a medium risk in 2 rivers in June month. As regard PFOS, 54% of the river water samples were classified as “high risk” for the aquatic environment. The remaining 46% of the samples were classified as “medium risk”.
<p>Lakes are integrators of environmental and climatic changes occurring within their contributing basins. Understanding the complex behavior of lakes in a changing environment is essential to effective water resource management and mitigation of climate change effects. The ESA CCI Lakes is a multi-disciplinary project (https://climate.esa.int/en/projects/lakes) combining expertise to exploit data to create the largest and longest possible consistent, global record of five lake climate variables: lake water level, extent, temperature, surface-leaving reflectance, and ice cover. The phase 1 version of the database covers 250 globally distributed lakes with temporal coverage, depending on parameter, ranging from 1992 up to 2019. The dataset is planned to expand to 2000 lakes in the second phase. The distribution of the dataset will be introduced over space and time. The potential of the dataset and in particular of data records on chlorophyll-a concentrations, is explored for Lake Trasimeno, a shallow eutrophic lake of central Italy which is a specific case study of the lakes CCI project included in the Long-Term Ecosystem Research (LTER) network. In situ measurements from LTER were used to evaluate satellite products as well as to complete the CCI data record. Meteo-climatic data were extracted to analyze the interrelationships between the trend in water parameters and climate factors. An in situ WISPstation sensor was also used to provide high frequency (every 15 minutes) information on chlorophyll-a and phycocyanin concentration for last two years.<br>We used Artificial Intelligence (AI) and Non-Parametric Multiplicative Regression (NPMR) techniques to analyze the data. Chlorophyll-a in Lake Trasimeno was dominated by a summer bloom consistently initiating in July and typically peaking in early September and was largely predicted by the time variable - accounting for 87% of feature importance. The North Atlantic Oscillation (NAO) was the next most important variable (4% feature importance) corroborated by NPMR and shown to be largely important during early to mid-September when a positive NAO, associated with high pressure and warm sunny weather, led to an increase in chlorophyll-a concentrations. Regional climatic indices as well as the more obvious nutrient drivers of algal blooms should therefore be considered in lake management. Comparing the high frequency WISPstation data (2018-2020) with the CCI dataset allows for detailed cross validation. Interestingly some of the rapid fluctuations visible from the satellite record that may have been interpreted as noise are supported by the in situ data. In addition, utilizing the phycocyanin results from the WISPstation showed, in near real time, how cyanophytes played a key role in the sudden increases and declines in chlorophyll-a in mid to late summer. Coupling climatic indices, nutrient concentrations and near real time phycocyanin concentrations could be indispensable to the management of blooms in high value recreational lakes such as Trasimeno.</p>
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