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Human norovirus (HNoV) GII.4 and Vibrio parahaemolyticus may be found in sea squirts. Antimicrobial effects of floating electrode-dielectric barrier discharge (FE-DBD) plasma (5-75 min, N2 1.5 m/s, 1.1 kV, 43 kHz) treatment were examined. HNoV GII.4 decreased by 0.11-1.29 log copy/µL with increasing duration of treatment time, and further by 0.34 log copy/µL when propidium monoazide (PMA) treatment was added to distinguish infectious viruses. The decimal reduction time (D1) of non-PMA and PMA-treated HNoV GII.4 by first-order kinetics were 61.7 (R2 = 0.97) and 58.8 (R2 = 0.92) min, respectively. V. parahaemolyticus decreased by 0.16-1.5 log CFU/g as treatment duration increased. The D1 for V. parahaemolyticus by first-order kinetics was 65.36 (R2 = 0.90) min. Volatile basic nitrogen showed no significant difference from the control until 15 min of FE-DBD plasma treatment, increasing after 30 min. The pH did not differ significantly from the control by 45-60 min, and Hunter color in "L" (lightness), "a" (redness), and "b" (yellowness) values reduced significantly as treatment duration increased. Textures appeared to be individual differences but were not changed by treatment. Therefore, this study suggests that FE-DBD plasma has the potential to serve as a new antimicrobial to foster safer consumption of raw sea squirts.

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The activity of lithium ions in electrolytes depends on their solvation structures. However, the understanding of changes in Li+ activity is still elusive in terms of interactions between lithium ions and solvent molecules. Herein, the chelating effect of lithium ion by forming [Li(15C5)]+ gives rise to a decrease in Li+ activity, leading to the negative potential shift of Li metal anode. Moreover, weakly solvating lithium ions in ionic liquids, such as [Li(TFSI)2 ]- (TFSI = bis(trifluoromethanesulfonyl)imide), increase in Li+ activity, resulting in the positive potential shift of LiFePO4 cathode. This allows the development of innovative high energy density Li metal batteries, such as 3.8 V class Li | LiFePO4 cells, along with introducing stable biphasic electrolytes. In addition, correlation between Li+ activity, cell potential shift, and Li+ solvation structure is investigated by comparing solvated Li+ ions with carbonate solvents, chelated Li+ ions with cyclic and linear ethers, and weakly solvating Li+ ions in ionic liquids. These findings elucidate a broader understanding of the complex origin of Li+ activity and provide an opportunity to achieve high energy density lithium metal batteries.

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Noroviruses (NoVs) are the most common causes of epidemic gastroenteritis, responsible for at least 50% of all gastroenteritis outbreaks worldwide and significant causes of foodborne illness. In the USA, approximately 21 million illnesses attributable to NoVs have annually occurred. Therefore, there is a great demand to develop a rapid, low-cost, and accurate detection method for NoVs. This study first reported colorimetric helicase-dependent amplification (HDA) methods based on specific primers integrated with HRPzyme for the rapid and sensitive detection of NoV GI and GII. The colorimetric HDA methods exhibited a detection limit of 10 copies mL-1 of each NoV GI and GII and were confirmed to be specific to each NoV GI and GII. The period required to complete the HDA method was 2 h, including a step of RNA extraction and cDNA synthesis without expensive instruments such as a thermal cycler and detector. The cutoff value of the method for the oyster artificially inoculated with a known amount of NoV was all 102 copies g-1 for NoV GI and GII. Therefore, the HDA method developed in this study can be useful tool for the on-site detection of NoVs in food samples.

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The present study investigated the distribution and antimicrobial susceptibility patterns of Vibrio parahaemolyticus in water samples and aquatic animals (fish and shrimp) from major aquaculture farms along the Korean coast in 2018. V. parahaemolyticus is the most common pathogen causing seafood-borne illness. The strain was detected in 34.7% of all samples tested, and was detected at higher levels during summer to autumn when the water temperature is higher. Although more than 90.0% of V. parahaemolyticus isolates were sensitive to 13 of the 15 antimicrobials tested, which is useful for treating V. parahaemolyticus infectious disease, the isolates exhibited higher resistance to two antibiotics (colistin and ampicillin), which should be excluded as treatment options for these infections. Koreans typically enjoy consuming raw seafood. To reduce the potential human health risk of raw seafood consumption, the prevalence and antimicrobial resistance of V. parahaemolyticus in aquaculture environments should be continuously valuated.

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Shellfish-growing areas in marine environments are affected by pollutants that mainly originate from land, including streams, domestic wastewater, and the effluents of wastewater treatment plants (WWTPs), which may function as reservoirs of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs). The objective of this study was to identify the occurrence and distribution of antibiotic resistance at five oyster sampling sites and 11 major inland pollution sources in the drainage basin of Kamak Bay, Republic of Korea. Culture-based methods were used to estimate the diversity and abundance of antibiotic-resistant Escherichia coli strains isolated from oysters and major inland pollution sources. The percentages of ARB and multiple antibiotic resistance index values were significantly high in discharge water from small fishing villages without WWTPs. However, the percentages of antibiotic-resistant E. coli isolates from oysters were low, as there was no impact from major inland pollutants. Fourteen ARGs were also quantified from oysters and major inland pollution sources. Although most ARGs except for quinolones were widely distributed in domestic wastewater discharge and effluent from WWTPs, macrolide resistance genes (ermB and msrA) were detected mainly from oysters in Kamak Bay. This study will aid in tracking the sources of antibiotic contamination in shellfish to determine the correlation between shellfish and inland pollution sources.

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Mild-acid Zn-MnO2 batteries have been considered a promising alternative to Li-ion batteries for large scale energy storage systems because of their high safety. There have been remarkable improvements in the electrochemical performance of Zn-MnO2 batteries, although the reaction mechanism of the MnO2 cathode is not fully understood and still remains controversial. Herein, the reversible dissolution/deposition (Mn2+/Mn4+) mechanism of the MnO2 cathode through a 2e- reaction is directly evidenced using solution-based analyses, including electron spin resonance spectroscopy and the designed electrochemical experiments. Solid MnO2 (Mn4+) is reduced into Mn2+ (aq) dissolved in the electrolyte during discharge. Mn2+ ions are then deposited on the cathode surface in the form of the mixture of the poorly crystalline Zn-containing MnO2 compounds through two-step reactions during charge. Moreover, the failure mechanism of mild-acid Zn-MnO2 batteries is elucidated in terms of the loss of electrochemically active Mn2+. In this regard, a porous carbon interlayer is introduced to entrap the dissolved Mn2+ ions. The carbon interlayer suppresses the loss of Mn2+ during cycling, resulting in the excellent electrochemical performance of pouch-type Zn-MnO2 cells, such as negligible capacity fading over 100 cycles. These findings provide fundamental insights into strategies to improve the electrochemical performance of aqueous Zn-MnO2 batteries.

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This study investigated the antiviral effects of floating electrode-dielectric barrier discharge (FE-DBD) plasma treatment (1.1 kV, 43 kHz, N2 1.5 m/s, 5-30 min) against human norovirus (HuNoV) GII.4 in Jogaejeotgal Infectivity was assessed using real-time quantitative-PCR (RT-qPCR) following treatment of samples with propidium monoazide (PMA) and sodium lauroyl sarcosinate (Sarkosyl). This study also investigated the effects of FE-DBD plasma treatment on Jogaejeotgal quality (assessed using pH value and Hunter colors). Following inoculation, the average titers of HuNoV GII.4 in Jogaejeotgal significantly (P < 0.05) decreased with increases in the FE-DBD plasma treatment time in both the non-PMA-treated and PMA + Sarkosyl-treated samples; in the non-PMA and PMA + Sarkosyl treated Jogaejeotgal, HuNoV GII.4 titers (log10 copy number/µL) were to: 3.16 and 2.95 (5 min), 2.90 and 2.48 (10 min), 2.82 and 2.40 (15 min), 2.58 and 2.26 (20 min), 2.48 and 2.06 (25 min), and 2.23 and 1.91 (30 min), respectively. The average titers of HuNoV demonstrated significant (P < 0.05) reductions of 0.35 log10 (55.3%) in PMA + Sarkosyl-treated samples compared with the non-PMA treated samples following exposure to 5-30 min of FE-DBD plasma. Reductions of >1-log for HuNoV in PMA + Sarkosyl- treated Jogaejeotgal required treatments of FE-DBD of 5-30 min. Using the first order kinetic model (R2 = 0.95), GII.4 decimal reduction time (D-value) resulting from FE-DBD plasma was 23.75 min. The pH and Hunter colors ("L", "a", and "b") were not significantly different (P > 0.05) between the untreated and FE-DBD plasma-treated Jogaejeotgal. Based on these results, the PMA + Sarkosyl/RT-qPCR method could be assessing HuNoV viability following 5-30 min treatment of FE-DBD plasma. Furthermore, may be an optimal treatment for Jogaejeotgal without altering the food quality (color and pH).

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In the title complex, [NiCl2(C5H5N)(C24H16N6)], the NiII ion is six-coordinated in a distorted octa-hedral coordination environment defined by three N atoms of the tridentate 2,3,5,6-tetra-2-pyridyl-pyrazine ligand, one N atom of the pyridine ligand and two Cl- anions, with the latter being mutually trans. The complex is disposed about a twofold rotation axis along the a axis. The complex molecules are connected in the crystal via C-H⋯Cl, C-H⋯N and π-π [closest inter-centroid separation = 3.7446 (14) Šbetween pyridyl rings].

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The title compound, [Pd(C14H10N4)2](NO3)2·CH3CN, consists of a cationic PdII complex, two anions and one lattice solvent mol-ecule, all in general positions. In the complex, the PdII cation is four-coordinated in a slightly distorted square-planar geometry defined by the four N atoms of two bidentate 2,3-di-2-pyridyl-pyrazine ligands. The complex, anions and solvent mol-ecule are linked by weak C-H⋯O inter-molecular hydrogen bonds. In the crystal, the complex mol-ecules are stacked in columns along the a axis.

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In the title compound, [Ni(C20H18Br2N2O2)], the NiII ion is four-coordinated in a slightly distorted square-planar coordination geometry defined by two N atoms and two O atoms of the tetra-dentate dianionic 4,4'-di-bromo-2,2'-[cyclo-hexane-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolato ligand. Pairs of complex mol-ecules are assembled by inter-molecular C-H⋯O hydrogen bonds with d(C⋯O) = 3.247 (4) Å.

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The title complex, [Pd(NO3)(C15H11N3)]NO3, comprises a cationic PdII complex and a nitrate anion. In the complex, the PdII cation is four-coordinated in a distorted square-planar coordination geometry defined by the three N atoms of the tridentate 2,2':6',2''-terpyridine ligand and one O atom from the NO3 - anion. In the crystal, the complex mol-ecules are stacked in columns along the a axis being connected by π-π stacking [closest inter-centroid separation between pyridyl rings = 3.878 (3) Å]. The connections between columns and anions to sustain a three-dimensional architecture are C-H⋯O hydrogen bonds.

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In the polymeric title complex, [MnBr2(C10H8N2)] n , the MnII ion, situated on a twofold axis of symmetry, is six-coordinated in a distorted octa-hedral coordination geometry defined by two N atoms from the chelating 2,2'-bi-pyridine ligand and four bridging Br- anions. The crystal reveals a one-dimensional Br-bridged chain along the c-axis direction with a zigzag topology. In the crystals, contacts between chains include π-π inter-actions between pyridyl rings [inter-centroid separation = 4.082 (1) Å].

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In the title compound, [Ni2Cl4(C18H12N6)2], the NiII ions are hexa-coordinated in a distorted octa-hedral coordination environment defined by three N atoms of the tridentate 2,4,6-tri-2-pyridyl-1,3,5-triazine ligand and three Cl- anions in a meridional geometry. The two NiII ions are bridged by two Cl anionic ligands, thereby forming a dinuclear complex. A crystallographic centre of inversion is located at the centroid of the Ni2Cl2 ring.

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This study investigates the effects of dielectric barrier discharge (DBD) plasma treatment (1.1 kV, 43 kHz, N2 1.5 L/min, 10~60 min) on human norovirus (HuNoV) GII.4 infectivity in fresh oysters. HuNoV viability in oysters was assessed by using propidium monoazide (PMA) as a nucleic acid intercalating dye before performing a real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Additionally, the impact of the DBD plasma treatment on pH and Hunter colors was assessed. When DBD plasma was treated for 60 min, the HuNoV genomic titer reduction without PMA pretreatment was negligible (<1 log copy number/µL), whereas when PMA treatment was used, HuNoV titer was reduced to >1 log copy number/µL in just 30 min. D1 and D2-value of HuNoV infectivity were calculated as 36.5 and 73.0 min of the DBD plasma treatment, respectively, using the first-order kinetics model (R2 = 0.98). The pH and Hunter colors were not significantly different (p > 0.05) between the untreated and DBD-plasma-treated oysters. The results suggest that PMA/RT-qPCR could help distinguish HuNoV infectivity without negatively affecting oyster quality following >30 min treatment with DBD plasma. Moreover, the inactivation kinetics of nonthermal DBD plasma against HuNoV in fresh oysters might provide basic information for oyster processing and distribution.

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We assessed the levels of fecal contamination and the originating species of 12 major inland pollutants in the drainage basin of Yeoja Bay. The presence of the human-specific (HF183), ruminant-specific (BacR and Rum-2-Bac), pig-specific (Pig-Bac-2 and Pig-2-Bac), avian-specific (GFD), and gull-specific (Gull2) markers in water samples (n = 34) from 12 inland pollution sources around Yeoja Bay was analyzed. HF183 was detected in 97% of the water samples, and all major inland pollution sources were contaminated with human feces. BacR and Rum-2-Bac were detected in 94% and 11%, respectively, of the water samples. Pig-2-Bac was not detected in the inland pollution sources, but site L5 might be contaminated with swine feces. Gull2 was not detected, whereas GFD was detected in 26% of the water samples. This study highlights the utility of a MST toolbox approach for characterizing the water quality of inland pollution sources and identifying the feces producing species.

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From 2011 to 2013, we conducted a full sanitary survey of pollution sources in proximity to a shellfish growing area in the Hansan-Geojeman region in Korea, which includes a designated shellfish growing area. In the sea area, 1152 seawater and 209 oyster samples were collected and examined to evaluate their bacteriological quality. There were 758 potential pollution sources in the drainage area, including 40 sources discharging water in 2013. Fecal coliform (FC) concentrations and impact radii of discharges ranged from 1.8 to 700,000 MPN/100 mL and from 3 to 600 m, respectively; however, the pollutants did not reach the designated area. This demonstrates that the dilution of waste was sufficient such that no significant impact occurred within the designated shellfish growing area. The variation in the FC levels of seawater was closely related to season and rainfall. The FC levels of seawater and oysters from the designated area met the regulation limits set by various countries. No pathogens were found in any oysters. The results of the survey indicate that the oysters produced in this area are apparently safe for raw consumption based on their bacterial quality.

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From 2009 to 2013, 80 oyster and 16 seawater samples were collected from the southern coast of Korea, including designated shellfish growing areas for export. The concentrations and bioaccumulation of heavy metals were determined, and a potential risk assessment was conducted to evaluate their hazards towards human consumption. The cadmium (Cd) concentration in oysters was the highest of three hazardous metals, including Cd, lead (Pb), and mercury (Hg), however, below the standards set by various countries. The metal bioaccumulation ratio in oysters was relatively high for zinc and Cd but low for Hg, Pb, arsenic, and chromium. The estimated dietary intakes of all heavy metals for oysters accounted for 0.02%-17.75% of provisional tolerable daily intake. The hazard index for all samples was far <1.0, which indicates that the oysters do not pose an appreciable hazard to humans for the metal pollutants of study.

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Na-ion batteries are an attractive alternative to Li-ion batteries for large-scale energy storage systems because of their low cost and the abundant Na resources. This Review provides a comprehensive overview of selected anode materials with high reversible capacities that can increase the energy density of Na-ion batteries. Moreover, we discuss the reaction and failure mechanisms of those anode materials with a view to suggesting promising strategies for improving their electrochemical performance.

RESUMEN

In the title complex, [PdBr2(C28H28P2)], the Pd(II) ion has a distorted cis-Br2P2 square-planar coordination geometry defined by two P atoms from the chelating 1,4-bis-(di-phenyl-phosphan-yl)butane ligand and two Br(-) anions. The four phenyl rings are inclined to the least-squares plane of the PdBr2P2 unit [maximum deviation = 0.1294 (7) Å], making dihedral angles of 66.3 (2), 87.2 (2), 68.8 (2) and 86.8 (2)°. The butyl-ene chain is in a gauche conformation, with a C-C-C-C torsion angle of 57.0 (8)°. Inter-molecular C-H⋯Br hydrogen bonds link the complex mol-ecules into supra-molecular layers in the ab plane. Weak π-π inter-actions, both intra- and inter-molecular [shortest inter-centroid distance = 4.598 (5) Å], are also noted in the three-dimensional architecture.

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The Pt(IV) ion in the title complex, [PtBr(4)(C(10)H(9)N(3))], is six-coordinated in a slightly distorted octa-hedral environment by two pyridine N atoms from a chelating di-2-pyridyl-amine (dpa) ligand and four Br(-) anions. The complex mol-ecule has mirror symmetry, with the Pt(IV) atom, two Br atoms and the central N atom of the dpa ligand lying on the mirror plane. The dpa ligand is not planar, showing a dihedral angle of 34.7 (2)° between the pyridine rings. The complex mol-ecules are connected by inter-molecular N-H⋯Br hydrogen bonds, forming chains along [001]. Inter-molecular C-H⋯Br hydrogen bonds and π-π inter-actions between the pyridine rings [centroid-centroid distance = 3.667 (4) Å] are also observed.