RESUMEN
The widespread presence of per- and polyfluoroalkyl substances (PFAS) in various environmental matrices and their adverse health effects have gained worldwide attention. Therefore, numerous studies have focused on human exposure to PFAS through different pathways, such as fish and drinking water, and little attention has been paid to milk consumption. This study aimed to explore the transfer of PFAS by investigating the occurrence of PFAS in cow feed, drinking water, and raw milk from 20 regions of China and to assess the risk of human exposure to PFAS from raw milk. In total, 13, 15, and 7 PFAS were detected in cow feed, drinking water, and raw milk with total concentrations (∑PFAS) of 5.59 ± 2.91 ng/g (mean ± standard deviation), 11.91 ± 23.12 ng/L, and 0.15 ± 0.13 ng/mL, respectively. Perfluoropentanoic acid (PFPeA) was dominant with a concentration of 2.28 ± 1.75 ng/g, approximately 40.7 % of ∑PFAS in feed. Perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA) were the dominant compounds found in drinking water at 4.80 ± 14.37 and 3.01 ± 6.06 ng/L, respectively. Additionally, PFOA (0.08 ± 0.09 ng/mL) was the most significant compound in raw milk, contributing 51.5 % of ∑PFAS. Moreover, the results of the carry-over rate (COR) were as follows: perfluorooctanesulfonic acid (PFOS, 29.58 %) > PFOA (15.78 %) > perfluorobutanesulfonic acid (PFBS, 9.45 %). According to the reference dose (RfD) established by the European Food Safety Authority (EFSA) in 2018, there is a potential toxicological hazard of PFOA exposure for preschool children through milk consumption. Notably, the health risk from PFOS for 1-year-old children in Central China exceeded that observed for humans in other regions and age groups. Our results showed that PFOS and PFOA were more likely to accumulate in cows and to be constantly transferred to milk, thus increasing the human health risk, especially in children.
Asunto(s)
Fluorocarburos , Leche , China , Animales , Leche/química , Fluorocarburos/análisis , Humanos , Medición de Riesgo , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/análisis , Monitoreo del Ambiente , Caprilatos/análisis , Agua Potable/química , Ácidos Alcanesulfónicos/análisis , Exposición Dietética/estadística & datos numéricos , Exposición Dietética/análisis , Contaminación de Alimentos/análisis , Contaminación de Alimentos/estadística & datos numéricosRESUMEN
We compared the ways of deproteinization for crude polysaccharides of Coprinus comatus, and finally selected Sevage method as the optimal method. Two main fractions of Ccp-I-A and Ccp-I-B were obtained after DEAE-52 cellulose and Sephadex G-200 chromatography, both were white-floc, soluble in water, insoluble in absolute ethyl alcohol, acetone and other organic solvents. Additionally, Fehling reagent, CTAB, Sulphuric acid-carbazole, I-KI and FeCl3 reaction were all negative. GC analysis showed Ccp-I-A was composed of mannitose, glucose and galactose in molar ratios of 2.03:9.52:1, whereas Ccp-I-B was composed of fucose and galactose with molar ratios of 1:5.21. Antioxidant activity test showed that Ccp-I-A and Ccp-I-B had good scavenging abilities on DPPH and ·OH. Compared to Ccp-I-B,the scavenging activity of Ccp-I-A was much stronger, and the scavenging rate could reach 72.1% and 55.3% respectively when the concentration was 300 µg/mL.
Asunto(s)
Coprinus/química , Depuradores de Radicales Libres/química , Polisacáridos/química , Depuradores de Radicales Libres/aislamiento & purificación , Polisacáridos/aislamiento & purificaciónRESUMEN
Matter described by quantum chromodynamics (QCD), the theory of strong interactions, may undergo phase transitions when its temperature and the chemical potentials are varied. QCD at finite temperature is studied in the laboratory by colliding heavy ions at varying beam energies. We present a test of QCD in the nonperturbative domain through a comparison of thermodynamic fluctuations predicted in lattice computations with the experimental data of baryon number distributions in high-energy heavy ion collisions. This study provides evidence for thermalization in these collisions and allows us to find the crossover temperature between normal nuclear matter and a deconfined phase called the quark gluon plasma. This value allows us to set a scale for the phase diagram of QCD.
RESUMEN
We study J/psi production at RHIC and LHC energies with both initial production at energies reached and the BNL Relativistic Heavy Ion Collider (RHIC) and CERN Large Hadron Collider (LHC) with regeneration. We solve the coupled set of transport equations for the J/psi distribution in phase space and the hydrodynamic equation for evolution of quark-gluon plasma. At RHIC, continuous regeneration is crucial for the J/psi momentum distribution while the elliptic flow is still dominated by initial production. At energies reached at the LHC energy, almost all the initially created J/psis are dissociated in the medium and regeneration dominates the J/psi properties.