Barely any data exist on metal speciation in the marine surface microlayer (SML), a rather complex environment, the study of which contributes to enhancement of knowledge on metal speciation and its ...effect to the ocean. Metal speciation is significant since life requires a wide variety of trace metals that are essential for the growth of the organisms. Ligand concentrations (
L
) of copper (Cu), zinc (Zn), and cadmium (Cd) were studied by anodic stripping voltammetry (ASV) in the SML of coastal areas within the Aegean Sea in the Eastern Mediterranean. Complexing capacities in the SML in decreasing order ranged for Cu from 29 to 201 nM (median 101 nM), for Zn 24–149 nM (45 nM), and for Cd 1.0–1.5 nM (1.4 nM). Average enrichment factors (EFs) of SML samples compared to subsurface ones (SSW) were calculated equal to 0.9 ± 0.8, 1.2 ± 0.5, and 1.7 ± 1.6 for
L
Zn
,
L
Cu
, and
L
Cd
, respectively. In five out of the six total paired samples of SML and SSW, lower concentrations of
L
Zn
were measured in the SML, which is not the case for
L
Cu
and
L
Cd
. Due to elevated dissolved Zn concentrations in the SML, its complexation is incomplete, contrary to those of Cu and Cd, which are fully complexed. These trace metals are essential nutrients for biological functions, hence any differences on their concentration and chemical speciation may directly influence the distribution of phytoplankton species in the upper water column and neuston. EFs of SML relatively to subsurface water ranged in average between 1.2 and 2.4 for total organic carbon (TOC), chlorophyll
a
(Chl
a
), and plankton, being generally >2 for most of the amino acids detected, demonstrating a relative enrichment of the SML in organic matter. A significant correlation was found between Cu ligands and dinoflagellates <20 μm, confirming older findings supporting that marine dinoflagellates of
Gymnodinium
genera produce Cu ligands. New insights are provided in the study and the importance of investigating bio-essential metal ions (Cu, Zn, Cd) and their organic complexes in the SML is pointed. Data on Zn and Cd complexing capacities in the SML are the first published so far.
Citrus fruits are cultivated in more than 100 countries around the world. The main citrus fruit–producing counties are Brazil, China, and the USA although the whole Mediterranean region ranks first ...worldwide. In Greece, citrus occupy an area of about 40.000 ha, representing 43% of total fruit crops. Soil quality is affected by long-term citrus cultivation. Soil organic matter is depleted in long-term citrus cultivation, in contrast to nutrients that seemed to increase in the following descending order: P
Olsen
> Na
ecxh
> NO
3
-N > K
ecxh
> Ca
ecxh
> Mg
ecxh
due to usual management practices. To evaluate the environmental impact due to broad use of Cu fungicides in long-term citrus cultivation, Cu total fraction and DTPA-extractable in agricultural soil were determined. Soil contamination rate was evaluated via proper indices of different sensitivities on their calculations. In particular, 22% of samples in older orchards were highly polluted based on the single-factor pollution index (PI). The index geo-accumulation index (Igeo) presented hysteresis in comparison with
PI
, which was more sensitive, comprehensive, and reliable, able to describe better the pollution classification of citrus soils. The calculation of monomial potential ecological risk for Cu showed that in older citrus groves, the average value was 11.8, while the max value was 49.8 indicating moderate ecological risk suggesting the negative environmental impact of intensive citrus cultivation. These results denote the need to preserve soil fertility and prevent potential toxic element accumulation due to long-term cultivation management practices, aiming to achieve soil sustainability and food security in National or Euro-Mediterranean scale.
A reliable and comparative fungicide index (
FI
) was assessed to describe the fungicide use in the agricultural land of Europe during the first 20 years of the twenty-first century (from 2000 to ...2018).
FI
is not uniform across EU
27
. The highest mean value (1.34 kg ha
−1
) of
FI
was observed in Southern Europe compared to the other sub-regions of the EU, while this variation existed mainly due to the inorganic fungicide use. The mean value of inorganic fungicide index (
FI
inorg
) in agricultural land area (
AL
) in Southern Europe was 1.69 kg ha
−1
, about three times higher than the average value (0.63 kg ha
−1
) across the EU. The higher mean values of organic fungicide index (
FI
org
) in conventional agricultural land area (
convAL
) was observed in Western Europe (0.54 kg ha
−1
), while an upward trend was observed in the
FI
org
mainly in Central and Eastern and Northern Europe during the period 2000–2018. Linear discriminant analysis (LDA) of 19 agri-environmental indicators (
FI
,
FI
org
, FI
inorg
,
agricultural land use, crop groups, fungicide chemical families) was assessed to describe this differentiation of the four geographical sub-regions of EU. Despite the linear growth of the organic farmland area, the fungicide use in the agricultural land remained relatively stable, while the larger the farm size (ha), the greater the amounts (kg of a.s.) of fungicides which were used in the cropland of EU. The impact assessment of each variable which was examined on the
FI
could contribute to the implementation of European agricultural policy, reducing in this way the environmental impact.
Stem refilling has been studied in many forest species, but its impact on olive trees remains underexplored. This study aims to examine the effect of varying fruit loads on stem refilling rates in ...olive trees. The experiment was conducted in a commercial olive orchard over two years, characterized by a biennial bearing cycle with minimal fruit production in 2021 (“OFF” year) and maximal fruit production in 2022 (“ON” year). Sap flow sensors measured the water volume differences traversing the apex and base of main branches in two experimental trees. Tree water status was monitored using psychrometers, and soil moisture content was continuously recorded. Results suggest that alternate bearing significantly affects the stem refilling process, while soil moisture availability also plays a pivotal role. During the “ON” year, water reserve consumption increased to 63.6% compared to the “OFF” year to meet the water requirements of developing fruits. Replenishment occurred at various times throughout the 24 h period, including early morning, afternoon, and night when stomatal conductance measurements indicated stomatal closure. During the “ON” year, olive trees experienced intense nocturnal replenishment of reserves, regardless of soil moisture, water vapor pressure deficit, or fruit development stage. These findings offer novel insights into olive trees’ rehydration dynamics that can be used to optimize irrigation scheduling and improve water use efficiency.
Land-use intensification, contrary to sustainable land management, has an impact on the healthiness of the environmental agroecosystem. To assess the environmental implications in abandoned land, ...olive groves and maize crops, the most sensitive and reliable edaphic indicators were measured to estimate plant species diversity and potentially toxic elements in soil, among different types of land-use. Species diversity presents a decrease in maize crops and olive groves compared to abandoned land. The families with the greatest species diversity were Poaceae, Asteraceae and Fabaceae in each land-use. From the results of the canonical correspondence analysis among species, sampling sites and selected environmental variables, a clear separation between species and sampling sites belonging to different types of land-use was found, presenting strong correlation with specific edaphic parameters (pH, Soil Organic Matter, Silt, Electrical Conductivity, Total Nitrogen, NO3-, P, K, Zn and Cu). Species diversity was reduced in maize crops due to anthropogenic interventions such as the excessive use of nitrogen and phosphate fertilizers and herbicides. Despite the fact that the lowest richness of plant species was found in olive groves, non-removal of crop residue preserves soil organic matter. In 7.4% of soil samples in olive groves, Cutotal concentrations were over 100 mg kg−1 denoting polluted soils, while the potentially toxic concentrations of bioavailable copper fraction (CuDTPA) probably lead to a decrease of species diversity. Future researches should therefore focus on the accumulation of toxic elements in agricultural land to preserve species diversity and a healthy environment.
The aim of this study is to evaluate the role of PZC and wettability of the catalysts in heterogeneous catalytic ozonation process. For that purpose, 18 solid materials examined as potential ...catalysts for heterogeneous catalytic ozonation, regarding the degradation of small amounts (4μΜ) of p-chlorobenzoic acid (p-CBA - typical micropollutant) at pH 7. The examined catalysts belong to three main categories, i.e., metal oxides/hydroxides, minerals, and carbons. Alumina 507, SiO2, Bayoxide, zeolite, calcite and dolomite were found to be the optimum catalysts with p-CBA removal rates higher than 99.4% after the 3rd min of the process. The obtained results indicate the importance of surface charge and the wettability degree of the catalysts. It was found that the affinity between ozone and the catalyst surface and the subsequent production of hydroxyl radicals (•OH) depends on these parameters. More specifically catalysts of high wettability and neutrally to slightly positive surface charged led to enhanced p-CBA degradation. The strongly negative or positive surface charged materials that present low wettability were found to decrease the •OH production. Although, in the gas phase ozone presents better affinity with the non-polar/hydrophobic surfaces, when it is dissolved in water and participates in aqueous phase oxidation reactions, the contact with the catalysts’ surface is enhanced by the higher wettability of the solids, promoting the production of •OH. In addition to the activation of ozone on the catalysts’ surface, it was shown that their efficiency is enhanced by the initial p-CBA adsorption on the surface of applied catalysts.
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•PZC value determines the affinity of ozone with a solids’ surface.•Neutral to slight positive surface charge enhance •OH production.•Wettability improves the contact of dissolved O3 with the active centers of catalyst surface.•Dissolved O3 has better affinity with the hydrophilic surfaces than the hydrophobic O3 gas.•Micropollutant adsorption contributes to heterogeneous catalytic efficiency.
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•Automated collection of health-related data and triggering of notifications were the main reasons for using smartwatches in interventional studies.•Smartwatch interventions have ...shown positive health outcomes for patients in most studies.•Challenges include: Charging frequency, Internet connection, data quality.•The evaluation of the implementation strategy in smartwatch research studies is needed.•The methodological quality of smartwatch studies should be improved.
The use of smartwatches has attracted considerable interest in developing smart digital health interventions and improving health and well-being during the past few years. This work presents a systematic review of the literature on smartwatch interventions in healthcare. The main characteristics and individual health-related outcomes of smartwatch interventions within research studies are illustrated, in order to acquire evidence of their benefit and value in patient care.
A literature search in the bibliographic databases of PubMed and Scopus was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, in order to identify research studies incorporating smartwatch interventions. The studies were grouped according to the intervention’s target disease, main smartwatch features, study design, target age and number of participants, follow-up duration, and outcome measures.
The literature search identified 13 interventions incorporating smartwatches within research studies with people of middle and older age. The interventions targeted different conditions: cardiovascular diseases, diabetes, depression, stress and anxiety, metastatic gastrointestinal cancer and breast cancer, knee arthroplasty, chronic stroke, and allergic rhinitis. The majority of the studies (76%) were randomized controlled trials. The most used smartwatch was the Apple Watch utilized in 4 interventions (31%). Positive outcomes for smartwatch interventions concerned foot ulcer recurrence, severity of symptoms of depression, utilization of healthcare resources, lifestyle changes, functional assessment and shoulder range of motion, medication adherence, unplanned hospital readmissions, atrial fibrillation diagnosis, adherence to self-monitoring, and goal attainment for emotion regulation. Challenges in using smartwatches included frequency of charging, availability of Internet and synchronization with a mobile app, the burden of using a smartphone in addition to a patient’s regular phone, and data quality.
The results of this review indicate the potential of smartwatches to bring positive health-related outcomes for patients. Considering the low number of studies identified in this review along with their moderate quality, we implore the research community to carry out additional studies in intervention settings to show the utility of smartwatches in clinical contexts.
Hypoglycaemia is one of the most common complications in diabetes, which can be life threatening if not managed appropriately. So far, research on hypoglycaemia prediction has been scarce, focusing ...on small cohorts linked to specific geographical regions, thus limiting the generalizability of the findings. In this paper, we developed and validated different machine learning models for next-day hypoglycaemia prediction in type 2 diabetes. We used a large international cohort comprising 669 participants, who had been regular users (for over a couple of years) of a mobile app for diabetes self-management and used common portable commercial devices for measuring their blood glucose and blood pressure levels, collecting in total 96121 observations. Random Forests (RF), Support Vector Machines, Adaptive Boosting and Feed-Forward Artificial Neural Networks were employed to train predictive models based on 10-day temporal sequences with blood glucose and blood pressure measurements towards estimating next day hypoglycaemic episodes. We used a leave-one-subject-out (LOSO) approach for model validation, and found that RF achieved the best accuracy (0.814) and F1-score (0.812) with sensitivity (0.805) and specificity (0.824) for next-day hypoglycaemia prediction. The results of this study provide an expedient and reliable app-based approach to accurately predict hypoglycaemia in day-to-day life, thereby facilitating patient and care provider awareness and potentially preventing other serious complications.
•Social robots can promote healthy behaviors in child healthcare.•Social robots should be considered in the design of psychological interventions.•Rigorous studies with social robot-based ...interventions are needed.
We present a systematic review of the literature on social robot interventions for child healthcare. The primary features and outcomes of studies using social robots are illustrated, to advance our comprehension towards the development of useful and effective social robot-based health interventions for the children.
We conducted a literature search in the bibliographic databases of PubMed and Scopus in order to find studies incorporating social robot interventions targeting child healthcare. The studies were synthesized according to the intervention's target, main robot features, study design, target age of children, number of participants, follow-up duration, and primary outcomes.
Our review reveals that most studies involved only a single session of interactions with the robot, and conducted with a limited number of participants. The interventions targeted alleviation of distress in children with cancer, exercise coaching, improvement of playfulness in children with intellectual disabilities, improvement of mental health, reduction of pain and distress in pediatric inpatient or outpatient settings, e.g., during needle insertions or vaccination, improvement of nutritional knowledge, and achievement of instant therapeutic or education goals in children with physical disabilities. The majority of the studies (85%) reported significant outcomes in technology acceptance, feasibility, enjoyment, engagement, achievement of therapeutic/education goals, pain, and mental health outcomes.
Significant outcomes in the mental state of children, suggest that social robots should be considered in the design of psychological interventions for children. More rigorous research in the area of evaluation of social robot interventions for child healthcare is warranted.
A systematic study of the effect of nitrogen levels in the cultivation medium of
Chlorella vulgaris
microalgae grown in photobioreactor (PBR) on biomass productivity, biochemical and elemental ...composition, fatty acid profile, heating value (HHV), and composition of the algae-derived fast pyrolysis (bio-oil) is presented in this work. A relatively high biomass productivity and cell concentration (1.5 g of dry biomass per liter of cultivation medium and 120 × 10
6
cells/ml, respectively) were achieved after 30 h of cultivation under N-rich medium. On the other hand, the highest lipid content (ca. 36 wt.% on dry biomass) was obtained under N-depletion cultivation conditions. The medium and low N levels favored also the increased concentration of the saturated and mono-unsaturated C16:0 and C18:1(n-9) fatty acids (FA) in the lipid/oil fraction, thus providing a raw lipid feedstock that can be more efficiently converted to high-quality biodiesel or green diesel (via hydrotreatment). In terms of overall lipid productivity, taking in consideration both the biomass concentration in the medium and the content of lipids on dry biomass, the most effective system was the N-rich one. The thermal (non-catalytic) pyrolysis of
Chlorella vulgaris
microalgae produced a highly complex bio-oil composition, including fatty acids, phenolics, ethers, ketones, etc., as well as aromatics, alkanes, and nitrogen compounds (pyrroles and amides), originating from the lipid, protein, and carbohydrate fractions of the microalgae. However, the catalytic fast pyrolysis using a highly acidic ZSM-5 zeolite, afforded a bio-oil enriched in mono-aromatics (BTX), reducing at the same time significantly oxygenated compounds such as phenolics, acids, ethers, and ketones. These effects were even more pronounced in the catalytic fast pyrolysis of
Chlorella vulgaris
residual biomass (after extraction of lipids), thus showing for the first time the potential of transforming this low value by-product towards high added value platform chemicals.
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