The uncontrolled introduction into the environment of plastic polymers have caused the dispersion of plastic fragments, known as Microplastics (MPs), that represent an important topic for public ...health. This study was the first to investigate the cause of the release of MPs in mineral waters and to estimate the concentration of MPs smaller than 10 μm both in number of particles and in mass unit. This study was carried out using a patent method regarding the extraction and analysis of MPs in more kind of matrix. Therefore, aims of this study were a) to assess the number of MPs with diameters of between 0.5 and 10 μm in mineral waters contained in plastic bottles, b) to evaluate if the physical-chemical properties of mineral waters and bottle quality could influence the release of MPs and, finally, c) to estimate the human daily exposure to MPs due to mineral water consumption.
The Mps were found in every sample. The main concentration of MPs was 656.8 μg/L ± 632.9 or 5.42E+07 p/L ± 1.95E+07. The main diameter of detected MPs was 2.44 μm ± 0.66 (where p/L, where p was the number of MPs). The Estimated Daily Intake (EDI) for adults and children were 1,531,524 p/kg/body-weight/day corresponding to 40.1 μg/kg/body-weight/day and 3,350,208 p/kg/body-weight/day corresponding to 87.8 μg/kg/body-weight/day, respectively.
The number of MPs contamination in bottled mineral waters was strongly correlated to the pH of waters and to plastic density of bottle. Otherwise, micrograms of MPs per liter and the MPs diameters were strongly affected by plastic thickness. The most mineral water brand contaminated by MPs was the one whose bottles were made from poor quality plastic.
In absence of reference values, it was no possible carried out a risk assessment for MPs exposure. It is fundamental to establish the reference method of analysis to monitoring every source of human intake.
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•New patent method of extraction and analysis of Microplastics.•Estimation of the concentration of Microplastics smaller than 10 μm both in number of particles and in mass unit.•Influence of physical-chemical properties of mineral waters and bottle quality on release of Microplastics.•Estimated Daily Intake of Microplastics for adults and children.
High quality factor whispering-gallery-mode microresonators are ideally suited for nonlinear optical interactions. We analyze, experimentally and theoretically, a variety of χ((3)) nonlinear ...interactions in silica microspheres, consisting of third harmonic generation and Raman assisted third order sum-frequency generation in the visible. A tunable, room temperature, cw multicolor emission in silica microspherical whispering-gallery-mode microresonators has been achieved by controlling the cavity mode dispersion and exciting nonequatorial modes for efficient frequency conversion.
While current recommendations on exercise type and volume have strong experimental bases, there is no clear evidence from large-sized studies indicating whether increasing training intensity provides ...additional benefits to subjects with type 2 diabetes.
To compare the effects of moderate-to-high intensity (HI) versus low-to-moderate intensity (LI) training of equal energy cost, i.e. exercise volume, on modifiable cardiovascular risk factors.
Pre-specified sub-analysis of the Italian Diabetes and Exercise Study (IDES), a randomized multicenter prospective trial comparing a supervised exercise intervention with standard care for 12 months (2005-2006).
Twenty-two outpatient diabetes clinics across Italy.
Sedentary patients with type 2 diabetes assigned to twice-a-week supervised progressive aerobic and resistance training plus exercise counseling (n = 303).
Subjects were randomized by center to LI (n = 142, 136 completed) or HI (n = 161, 152 completed) progressive aerobic and resistance training, i.e. at 55% or 70% of predicted maximal oxygen consumption and at 60% or 80% of predicted 1-Repetition Maximum, respectively, of equal volume.
Hemoglobin (Hb) A(1c) and other cardiovascular risk factors; 10-year coronary heart disease (CHD) risk scores.
Volume of physical activity, both supervised and non-supervised, was similar in LI and HI participants. Compared with LI training, HI training produced only clinically marginal, though statistically significant, improvements in HbA(1c) (mean difference -0.17% 95% confidence interval -0.44,0.10, P = 0.03), triglycerides (-0.12 mmol/l -0.34,0.10, P = 0.02) and total cholesterol (-0.24 mmol/l -0.46, -0.01, P = 0.04), but not in other risk factors and CHD risk scores. However, intensity was not an independent predictor of reduction of any of these parameters. Adverse event rate was similar in HI and LI subjects.
Data from the large IDES cohort indicate that, in low-fitness individuals such as sedentary subjects with type 2 diabetes, increasing exercise intensity is not harmful, but does not provide additional benefits on cardiovascular risk factors.
www.ISRCTN.org ISRCTN-04252749.
This study was designed to compare cadmium (Cd) and lead (Pb) bioaccumulation in three species of oniscidean isopods – Armadillidium granulatum Brandt, Armadillidium vulgare (Latreille) and Porcellio ...laevis Latreille which were exposed for three weeks to a contaminated diet, and to determine the morphological and ultrastructural changes in hepatopancreas. Metal accumulation, determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), was linearly associated with the exposed concentration and was a function of the metal and the species tested. All three species accumulated lower levels of Pb than Cd. A. vulgare accumulated the largest concentration of Pb, especially at the higher doses, whereas P. laevis showed the greatest Cd accumulation, and the highest Cd concentration was lethal for all exposed species. The highest concentrations of Pb and Cd induced significant changes both in the general morphology of tubules and in the ultrastructural organization of epithelial cells in hepatopancreas. Some Pb/Cd induced alterations include: brush border disorganization; reduction of the basal labyrinth formed by the plasma membrane; condensation of some cytoplasm areas and of chromatin; rough endoplasmic reticulum and mitochondrial alterations; increase of secondary lysosomes and of type B granules in S cells. Some of the ultrastructural changes observed overlap with those induced by prolonged starvation, whereas others can be useful biomarkers of heavy metal toxicity. This study has confirmed that in terrestrial isopods, the accumulation of the different metals occurs in a species-specific manner; therefore ecological monitoring and assessment studies should consider each species individually. The research has confirmed that in the terrestrial isopods the accumulation of the different metals occurs in a species-specific way; therefore each species should first be evaluated in view of its employ in biomonitoring programs.
•Terrestrial isopods respond to Cd and Pb contamination in a species-specific way.•Cd and Pb cause dose-dependent morphology and ultrastructure hepatopancreas changes.•Bioaccumulation capacity was higher for Cd than for Pb in all three species studied.•Porcellio laevis is particularly sensitive to Cd exposure.•The microvillous border of hepatopancreas cells is the main target of heavy metals.
Due to population growth, urbanization and economic development, demand for freshwater in urban areas is increasing throughout Europe. At the same time, climate change, eutrophication and pollution ...are affecting the availability of water supplies. Sicily, a big island in southern Italy, suffers from an increasing drought and consequently water shortage. In the last decades, in Sicilian freshwater reservoirs several Microcystis aeruginosa and more recently Planktothrix rubescens blooms were reported.
The aims of the study were: (1) identify and quantify the occurring species of cyanobacteria (CB), (2) identify which parameters, among those investigated in the waters, could favor their growth, (3) set up a model to identify reservoirs that need continuous monitoring due to the presences, current or prospected, of cyanobacterial blooms and of microcystins, relevant for environmental and, consequentially, for human health.
Fifteen artificial reservoirs among the large set of Sicilian artificial water bodies were selected and examined for physicochemical and microbiological characterization. Additional parameters were assessed, including the presence, identification and count of the cyanobacterial occurring species, the measurement of microcystins (MCs) levels and the search for the genes responsible for the toxins production. Principal Component Analysis (PCA) was used to relate environmental condition to cyanobacterial growth.
Water quality was poor for very few parameters, suggesting common anthropic pressures, and PCA highlighted clusters of reservoirs vulnerable to hydrological conditions, related to semi-arid Mediterranean climate and to the use of the reservoir. In summer, bloom was detected in only one reservoir and different species was highlighted among the Cyanobacteria community. The only toxins detected were microcystins, although always well below the WHO reference value for drinking waters (1.0 μg/L). However, molecular analysis could not show the presence of potential cyanotoxins producers since a few numbers of cells among total could be sufficient to produce these low MCs levels but not enough high to be proved by the traditional molecular method applied. A simple environmental risk-based model, which accounts for the high variability of both cyanobacteria growth and cyanotoxins producing, is proposed as a cost-effective tool to evaluate the need for monitoring activities in reservoirs aimed to guarantee supplying waters safety.
•PCA was a useful method to investigate quality of surface waters and the parameters influencing cyanobacteria growth.•Nutrients and micronutrients (Fe, Mn, Cl), pH, conductivity and turbidity seem to affect the cyanobacteria bloom.•Prediction model identified the need of continuous monitoring the basins susceptible to future blooms.•The status of Sicilian freshwater reservoirs would be improved adopting a better treatment and management of wastewaters.
Magneto-plasmonic nanostructures functionalized with cell targeting units are of great interest for nanobiotechnology applications. Photothermal treatment of cells targeted with antibody ...functionalized nanostructures and followed by magnetic isolation, allows killing selected cells and hence is one of the applications of great interest. The magneto-plasmonic nanostructures reported herein were synthesized using naked gold and magnetite nanoparticles obtained through a green approach based on laser ablation of bulk materials in water. These particles do not need purifications steps for biocompatibility and are functionalized with a SERRS (surface enhanced resonance Raman scattering) active molecule for detection and with an antibody for targeting prostate tumor cells. Quantitative results for the cell targeting and selection efficiency show an overall accuracy of 94% at picomolar concentrations. The photothermal treatment efficiently kills targeted and magneto-selected cells producing a viability below 5% after 3 min of irradiation, compared with almost 100% viability of incubated and irradiated, but non targeted cells.
The ENSO Transition Probabilities Conti, G.; Navarra, A.; Tribbia, J.
Journal of climate,
07/2017, Volume:
30, Issue:
13
Journal Article
Peer reviewed
Open access
ENSO is investigated here by considering it as a transition from different states. Transition probability matrices can be defined to describe the evolution of ENSO in this way. Sea surface ...temperature anomalies are classified into four categories, or states, and the probability to move from one state to another has been calculated for both observations and a simulation from a GCM. This could be useful for understanding and diagnosing general circulation models elucidating the mechanisms that govern ENSO in models. Furthermore, these matrices have been used to define a predictability index of ENSO based on the entropy concept introduced by Shannon. The index correctly identifies the emergence of the spring predictability barrier and the seasonal variations of the transition probabilities. The transition probability matrices could also be used to formulate a basic prediction model for ENSO that was tested here on a case study.
The uncontrolled introduction into the environment of plastic polymers have caused the dispersion of plastic debries, known as microplastics (MPs), that represent an important topic for environmental ...and human health threats. So far, the absence of effective and efficient extraction methods of MPs (especially for plastic particles with diameters inferior than 10 µm) from complex matrices (water, food, etc.) did not allow to perform the risk estimation and, the consequent assessment of the health impact associated with the exposure to these emergent contaminants.
In this paper, a new patented method for the extraction and determination of micro- and nano-plastics in organic and inorganic matrix samples is reported. The method applied in the study has been nationally and internationally protected. The code of the submitted request of international patent's extension in several country of world is PCT/IB2019/051,838 of 7 March 2019, coupled with the accepted Italian patent n. 102,018,000,003,337 of March 7 of 2018 entitled “Method for extraction and determination of microplastics in samples with organic and inorganic matrices”. The method applied to our study is based on sedimentation of the particles with density higher than 1 g/cm3. The method can be applied to organic and inorganic samples as water, food, soil, waste, air, biological sample (blood, urine, tissues, etc.).
After acid digestion of sample matrix, MPs are recovered by sedimentation in dichloromethane and then they are dispersed in metallic stub. Analysis is performed by SEM-EDX.•New method for the extraction and determination of total microplastics <10 µm.•The method is based on the sedimentation of particles with density higher than 1 g/cm3.•The method can be applied to organic (food, soil, biological sample, etc..) and inorganic samples.•Total micro- and nano-plastics quantification is performed by SEM-EDX.
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