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Traditionally the accuracy assessment of a hard raster-based land use land cover (LULC) map uses a reference data set that contains one LULC class per pixel, which is the class that has the largest area in each pixel. However, when mixed pixels exist in the reference data, this is a simplification of reality that has implications for both the accuracy assessment and subsequent applications of LULC maps, such as area estimation. This paper demonstrates how the use of class proportions in the reference data set can be used easily within regular accuracy assessment procedures and how the use of class proportions can affect the final accuracy assessment. Using the CORINE land cover map (CLC) and the more detailed Urban Atlas (UA), two accuracy assessments of the raster version of CLC were undertaken using UA as the reference and considering for each pixel: (i) the class proportions retained from the UA; and (ii) the class with the majority area. The results show that for the study area and the classes considered here, all accuracy indices decrease when the class proportions are considered in the reference database, achieving a maximum difference of 16% between the two approaches. This demonstrates that if the UA is considered as representing reality, then the true accuracy of CLC is lower than the value obtained when using the reference data set that assigns only one class to each pixel. Arguments for and against using class proportions in reference data sets are then provided and discussed. [ABSTRACT FROM AUTHOR]

The aim of the study was to study the status of cognitive functions in hypertensive patients, patients with hypothyroidism, and in patients with combination of these diseases, taking into account the state of disease compensation. 67 patients (36 men and 31 women), average age - 49.84±2.83 years were examined. The control group (CG) consisted of 18 practically healthy individuals (8 men and 10 women). Patients who received appropriate nosology treatment were divided into 3 groups: Group I - 21 patients with hypertension, systolic blood pressure (SBP) - 134.26±5.23 mm Hg, diastolic blood pressure (DBP) - 84.37±4.51 mm Hg; Group II - 18 patients with hypothyroidism, thyrotropic hormone (TSH) - 3.16±0.79 mIU/L, stage of hypothyroidism compensation was diagnosed in 83.3%, subcompensation - in 16.7%; Group III - 28 patients with hypertension (SBP 145.52±5.45 mm Hg; DBP 82.41±3.86 mm Hg) with concomitant hypothyroidism (TSH - 2.92±0.78 mIU/L, stage of compensation for hypothyroidism was diagnosed in 85.7%, subcompensation - in 14.3% of cases. Information about visits to the therapist/cardiologist/family doctor and endocrinologist was used to analyze the therapeutic correction of the disease: ambulatory medical records of patients with measurement of blood pressure (BP) and TSH during the disease were processed. To assess cognitive functions, Mini Mental State Examination (MMSE) and the Addenbrooke's cognitive examination (ACE-R) were used. The relationship of average blood pressure data in patients with hypertension and TSH in patients with hypothyroidism during the disease period and the level of cognitive function was investigated. The average level of office BP (SBP/DBP) in Groups I and III compared to CG during the examination was: SBP 134.26±5.23 mm Hg (p=0.047), DBP 84.37±4.51 mm Hg (p=0.041) in Group I; SBP 145.52±5.45 mm Hg (p=0.031), DBP 82.41±3.86 mm Hg (p=0.050) in Group III. Analyzing the TSH levels it was found that at the time of the physical examination of patients in Group II the TSH was 3.16±0.79 mIU/L (p=0.009), the stage of compensation was diagnosed in 83.3%, subcompensation - in 16.7%; in Group III the TSH was 2.92±0.78 mIU/L (p=0.027), the stage of hypothyroidism compensation was diagnosed in 85.7%, subcompensation - in 14.3%. When evaluating MMSE scores, the proportion of patients in Groups I-III who had cognitive impairment (CI) was 6.9%, 10.3% and 13.8% respectively. On individual assessment of ACE-R test scores, CI in Groups I-III was in 6.4%, 9.6% and 13.8% respectively. A detailed analysis of the patterns of the ACE-R scale revealed that patients in Group I had a significantly lower score in the memory domain (22.68±0.96, p=0.037); patients in Group II had a low score in the concentration domain (15.85±1.14, p=0.045) and executive functions domain (11.62±8.63, p=0.041). Taking into account the interaction of factors (hypertension and hypothyroidism), it was found that in 40% of patients in Group III the most affected cognitive domains were memory (21.12±0.98, p=0.012) and speech (22.41±2.32, p=0.038); 60% of patients had problems with executive functions (11.90±9.17, p=0.033) as well as with visual-spatial skills (14.40±8.15, p=0.045). MMSE test showed a significantly lower score in the memory domain (1.87±0.46, p=0.008) in Group I, patients of Group II had a significantly lower score in the concentration domain (2.53±0.54, p=0.018). Basing on the interaction of factors (hypertension and hypothyroidism), it was found that in 45% of patients the most affected cognitive domain was memory (2.3±0.38, p=0.028), and 55% suffer from impaired speech, praxis (7.48±0.59, p=0.018) and perception (2.45±0.67, p=0.028). A retrospective analysis of medical records regarding the control of patients' diseases was conducted. It was found that the average level of SBP/DBP in Groups I and III was 154.38±5.11 (p=0.000) \ 96.47±3.49 (p=0.006) mm Hg; 158.26±5.64 (p=0.001) \ 98.42±4.93 (p=0.005) mmHg, respectively. The TSH level over the disease period in patients of Groups II and III was 7.14±2.37 mIU/L (p=0.002) and 8.03±3.77 mIU/L (p=0.000), respectively, which was different from the data obtained in the last study. Retrospective analysis of medical records made it possible to establish a real long-term control of blood pressure, TSH in patients with hypertension, in patients with hypothyroidism and in patients with combination of these diseases, which caused CI in 6.9% of patients with hypertension, in 10.3% of patients with hypothyroidism and in 13.8% of patients with combined pathology based on MMSE test results. The ACE-R test results show the same sequence. Individual assessment of ACER test scores revealed CI in Groups I-III: 6.4%; 9.6% and 13.8%, respectively. The MMSE scale evaluates the selective deficits of one or more cognitive domains; the ACE-R scale is a wide-ranging study tool but it should be noted that the implementation of this scale requires time outlays. [ABSTRACT FROM AUTHOR]

The aim of this paper is to perform a preliminary analysis of the compatibility and quality of the available time series of land cover data available for continental Portugal, in particular, Climate Change Initiative Land Cover maps, which are available annually from 1992 to 2015; CORINE Land Cover and the Urban Atlas for 2006 and 2012; and the Portuguese Carta de Ocupação do Solo for 2007 and 2010. Changes were first identified per product between the different data sets for consecutive dates and then a comparison was made between products. This was followed by validation of two study areas using the COS and UA as reference products. The results show that increases in urbanization are visible in all pairs of products but that the amount of change varies. Moreover, some changes are not in the same direction but may be attributable to classes with small areas and the coarser resolution of the CCI LC maps compared to the other products. The CCI LC maps also overestimate the forest/natural vegetation class by 11–13%, which is also the largest class in Portugal. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) is a global environmental pollutant with neurotoxic effects. Exposure to MeHg via consumption of seafood and fish can severely impact fetal neurobehavioral development even when MeHg levels in maternal blood are as low as about 5 μg/L, which the mother tolerates well. Persistent motor dysfunctions and cognitive deficits may result from trans-placental exposure. The present review summarizes current knowledge on the mechanisms of MeHg toxicity during the period of nervous system development. Although cerebellar Purkinje cells are MeHg targets, the actions of MeHg on thiol components in the neuronal cytoskeleton as well as on mitochondrial enzymes and induction of disturbances of glutamate signaling can impair extra-cerebellar functions, also at levels well tolerated by adult individuals. Numerous herbal substances possess neuroprotective effects, predominantly represented by natural polyphenolic molecules that might be utilized to develop natural drugs to alleviate neurotoxicity symptoms caused by MeHg or other Hg compounds., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Spatially explicit information on forest management at a global scale is critical for understanding the status of forests, for planning sustainable forest management and restoration, and conservation activities. Here, we produce the first reference data set and a prototype of a globally consistent forest management map with high spatial detail on the most prevalent forest management classes such as intact forests, managed forests with natural regeneration, planted forests, plantation forest (rotation up to 15 years), oil palm plantations, and agroforestry. We developed the reference dataset of 226 K unique locations through a series of expert and crowdsourcing campaigns using Geo-Wiki ( https://www.geo-wiki.org/ ). We then combined the reference samples with time series from PROBA-V satellite imagery to create a global wall-to-wall map of forest management at a 100 m resolution for the year 2015, with forest management class accuracies ranging from 58% to 80%. The reference data set and the map present the status of forest ecosystems and can be used for investigating the value of forests for species, ecosystems and their services., (© 2022. The Author(s).)

It is well established that nighttime radiance, measured from satellites, correlates with economic prosperity across the globe. In developing countries, areas with low levels of detected radiance generally indicate limited development - with unlit areas typically being disregarded. Here we combine satellite nighttime lights and the world settlement footprint for the year 2015 to show that 19% of the total settlement footprint of the planet had no detectable artificial radiance associated with it. The majority of unlit settlement footprints are found in Africa (39%), rising to 65% if we consider only rural settlement areas, along with numerous countries in the Middle East and Asia. Significant areas of unlit settlements are also located in some developed countries. For 49 countries spread across Africa, Asia and the Americas we are able to predict and map the wealth class obtained from ~2,400,000 geo-located households based upon the percent of unlit settlements, with an overall accuracy of 87%., (© 2022. The Author(s).)

To meet the ambitious objectives of biodiversity and climate conventions, the international community requires clarity on how these objectives can be operationalized spatially and how multiple targets can be pursued concurrently. To support goal setting and the implementation of international strategies and action plans, spatial guidance is needed to identify which land areas have the potential to generate the greatest synergies between conserving biodiversity and nature's contributions to people. Here we present results from a joint optimization that minimizes the number of threatened species, maximizes carbon retention and water quality regulation, and ranks terrestrial conservation priorities globally. We found that selecting the top-ranked 30% and 50% of terrestrial land area would conserve respectively 60.7% and 85.3% of the estimated total carbon stock and 66% and 89.8% of all clean water, in addition to meeting conservation targets for 57.9% and 79% of all species considered. Our data and prioritization further suggest that adequately conserving all species considered (vertebrates and plants) would require giving conservation attention to ~70% of the terrestrial land surface. If priority was given to biodiversity only, managing 30% of optimally located land area for conservation may be sufficient to meet conservation targets for 81.3% of the terrestrial plant and vertebrate species considered. Our results provide a global assessment of where land could be optimally managed for conservation. We discuss how such a spatial prioritization framework can support the implementation of the biodiversity and climate conventions., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Since the collapse of the Soviet Union and transition to a new forest inventory system, Russia has reported almost no change in growing stock (+ 1.8%) and biomass (+ 0.6%). Yet remote sensing products indicate increased vegetation productivity, tree cover and above-ground biomass. Here, we challenge these statistics with a combination of recent National Forest Inventory and remote sensing data to provide an alternative estimate of the growing stock of Russian forests and to assess the relative changes in post-Soviet Russia. Our estimate for the year 2014 is 111 ± 1.3 × 10 9 m 3 , or 39% higher than the value in the State Forest Register. Using the last Soviet Union report as a reference, Russian forests have accumulated 1163 × 10 6 m 3  yr -1 of growing stock between 1988-2014, which balances the net forest stock losses in tropical countries. Our estimate of the growing stock of managed forests is 94.2 × 10 9 m 3 , which corresponds to sequestration of 354 Tg C yr -1 in live biomass over 1988-2014, or 47% higher than reported in the National Greenhouse Gases Inventory.

We provide a global, spatially explicit characterization of 47 terrestrial habitat types, as defined in the International Union for Conservation of Nature (IUCN) habitat classification scheme, which is widely used in ecological analyses, including for quantifying species' Area of Habitat. We produced this novel habitat map for the year 2015 by creating a global decision tree that intersects the best currently available global data on land cover, climate and land use. We independently validated the map using occurrence data for 828 species of vertebrates (35152 point plus 8181 polygonal occurrences) and 6026 sampling sites. Across datasets and mapped classes we found on average a balanced accuracy of 0.77 ([Formula: see text]0.14 SD) at Level 1 and 0.71 ([Formula: see text]0.15 SD) at Level 2, while noting potential issues of using occurrence records for validation. The maps broaden our understanding of habitats globally, assist in constructing area of habitat refinements and are relevant for broad-scale ecological studies and future IUCN Red List assessments. Periodic updates are planned as better or more recent data becomes available.

There is an increasing evidence that smallholder farms contribute substantially to food production globally, yet spatially explicit data on agricultural field sizes are currently lacking. Automated field size delineation using remote sensing or the estimation of average farm size at subnational level using census data are two approaches that have been used. However, both have limitations, for example, automatic field size delineation using remote sensing has not yet been implemented at a global scale while the spatial resolution is very coarse when using census data. This paper demonstrates a unique approach to quantifying and mapping agricultural field size globally using crowdsourcing. A campaign was run in June 2017, where participants were asked to visually interpret very high resolution satellite imagery from Google Maps and Bing using the Geo-Wiki application. During the campaign, participants collected field size data for 130 K unique locations around the globe. Using this sample, we have produced the most accurate global field size map to date and estimated the percentage of different field sizes, ranging from very small to very large, in agricultural areas at global, continental, and national levels. The results show that smallholder farms occupy up to 40% of agricultural areas globally, which means that, potentially, there are many more smallholder farms in comparison with the two different current global estimates of 12% and 24%. The global field size map and the crowdsourced data set are openly available and can be used for integrated assessment modeling, comparative studies of agricultural dynamics across different contexts, for training and validation of remote sensing field size delineation, and potential contributions to the Sustainable Development Goal of Ending hunger, achieve food security and improved nutrition and promote sustainable agriculture., (© 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.)

Knowledge of the spatial distribution of agricultural abandonment following the collapse of the Soviet Union is highly uncertain. To help improve this situation, we have developed a new map of arable and abandoned land for 2010 at a 10 arc-second resolution. We have fused together existing land cover and land use maps at different temporal and spatial scales for the former Soviet Union (fSU) using a training data set collected from visual interpretation of very high resolution (VHR) imagery. We have also collected an independent validation data set to assess the map accuracy. The overall accuracies of the map by region and country, i.e. Caucasus, Belarus, Kazakhstan, Republic of Moldova, Russian Federation and Ukraine, are 90±2%, 84±2%, 92±1%, 78±3%, 95±1%, 83±2%, respectively. This new product can be used for numerous applications including the modelling of biogeochemical cycles, land-use modelling, the assessment of trade-offs between ecosystem services and land-use potentials (e.g., agricultural production), among others.

Bastin et al (Reports, 12 May 2017, p. 635) claim to have discovered 467 million hectares of new dryland forest. We would argue that these additional areas are not completely "new" and that some have been reported before. A second shortcoming is that not all sources of uncertainty are considered; the uncertainty could be much higher than the reported value of 3.5%., (Copyright © 2017, American Association for the Advancement of Science.)

A global reference data set on cropland was collected through a crowdsourcing campaign using the Geo-Wiki crowdsourcing tool. The campaign lasted three weeks, with over 80 participants from around the world reviewing almost 36,000 sample units, focussing on cropland identification. For quality assessment purposes, two additional data sets are provided. The first is a control set of 1,793 sample locations validated by students trained in satellite image interpretation. This data set was used to assess the quality of the crowd as the campaign progressed. The second data set contains 60 expert validations for additional evaluation of the quality of the contributions. All data sets are split into two parts: the first part shows all areas classified as cropland and the second part shows cropland average per location and user. After further processing, the data presented here might be suitable to validate and compare medium and high resolution cropland maps generated using remote sensing. These could also be used to train classification algorithms for developing new maps of land cover and cropland extent.

Global land cover is an essential climate variable and a key biophysical driver for earth system models. While remote sensing technology, particularly satellites, have played a key role in providing land cover datasets, large discrepancies have been noted among the available products. Global land use is typically more difficult to map and in many cases cannot be remotely sensed. In-situ or ground-based data and high resolution imagery are thus an important requirement for producing accurate land cover and land use datasets and this is precisely what is lacking. Here we describe the global land cover and land use reference data derived from the Geo-Wiki crowdsourcing platform via four campaigns. These global datasets provide information on human impact, land cover disagreement, wilderness and land cover and land use. Hence, they are relevant for the scientific community that requires reference data for global satellite-derived products, as well as those interested in monitoring global terrestrial ecosystems in general.