A comparative study on the distribution behavior of microplastics through FT-IR analysis on different land uses in agricultural soils.

Plastic materials have been variously exposed to arable land for decades through soil mulching, plastic housing, and sewage sludge composting. Their mechanical abrasion and biochemical degradation induce the proliferation of myriad microplastics that can further be broken into smaller nano-sized pieces that can be further accumulated in living organisms (including soil invertebrates, fruits, and vegetables); they can also be widely dispersed in neighboring environments. Despite the intensive use of plastics in agriculture, little is known about their origin of occurrence and environmental fate, especially with a size below 100 µm. Therefore, in this study, microplastics with a size in the range of 20-2,000 µm were investigated in soil samples obtained from three different conditions of land uses: tilled with plastic mulch, bare ground (i.e., uncultivated land), and in between the greenhouses of the farmland D located in Namyangju-si, Gyeonggi-do, Republic of Korea. They were primarily identified using Fourier transform infrared (FT-IR) spectroscopy coupled with a microscope. Prior to performing the analysis, microplastic extraction from the soil samples was validated using standardized high-density polyethylene (HDPE) microplastics of various sizes ranging from 20 to 500 µm. As a result, the number of microplastics was estimated to be (241 ± 52), (195 ± 37), and (306 ± 56) particles per kg of dry soil in tillage, bare ground, and in between greenhouses, respectively. They consist of polyethylene (PE), polypropylene (PP), and poly(ethylene terephthalate) (PET), which are the basic constituents of commonly used agricultural products. The particle size distribution depends on the type of plastic, the time elapsed since their usage, and the degree and duration of environmental exposure; the plastic particle sizes were smaller in tillage and around the greenhouses since agricultural films have been weathered for a long time, whereas those with relatively large sizes were found in the uncultivated.

Rapid surface degradation of co-axially arranged polypropylene globules by nanoporous carbonized TiO2 assisted with UV-C.

The degradation of plastics, especially polypropylene (PP), is difficult since it is the most hydrophobic polymer. Photocatalytic degradation of PP films has been reported to be one of the most efficient degradation techniques. However, it is still insignificant to employ it in field applications. In this study, TiO2 nanoparticles supported on amorphous carbon with nanoporosity (TiO2@NC) are used as a photocatalyst to degrade macro-sized co-axially oriented PP globules under the influence of UV-C irradiation. Surface characterization such as SEM, ATR-FTIR, and XPS of the PP globules was performed. The SEM images distinctly showed the surface degradation phenomenon. Interestingly, the ATR-FTIR spectra demonstrated a significant rise in the band intensity in the -OH radical region and fairly in the CO region as well, with the increase in the photocatalytic time. Surprisingly, in the XPS spectra, the intensity of C-1s spectra kept on falling, and the intensity of O-1s spectra kept on rising with the increase in the photocatalytic time. The higher surface area due to nanoporosity of TiO2@NC enhanced the photocatalytic degradation of PP globules than previously reported studies. TiO2@NC seems to be a potential catalyst for the degradation of different types of polymers.

Comparison of the bacterial viability assessments for the disinfected quarantined water along with an effect of total residual oxidants.

The water discarded from the quarantine station inspecting aquatic products can be served as an influx channel of invasive microorganisms to our own ecosystem. This study thus compared the viability of three different pathogenic bacteria (Escherichia coli, Vibrio harveyi, and Enterococcus faecalis) in either seawater or freshwater after their disinfection. For that, they were treated by ozonation (2.08 mM of ozone), ultraviolet irradiation (UVC-254), or thermal treatment (90℃) for 10 min, during which their resultant viability was monitored using colorimetric ATP assay, colony counting, and real-time quantitative RT-PCR. From this, ATP measurement and real-time quantitative RT-PCR have proved to be a much stronger correlation built in the fraction of each of their assays versus the colony counting, although they differed in the type of disinfection implemented. Especially, ATP assay was the most sensitively influenced by high levels of total residual oxidants (TRO) undesirably produced during the ozonation of V. harveyi and E. faecalis in seawater, although easily and shortly measured within 1 h, with higher accuracy. Aside from that, the real-time quantitative RT-PCR had a stronger correlation versus either that of seawater ozonation or thermal treatment. It is decided referring to measurement time and convenience in the field that ATP assay can be more reliably used in bacterial cell viability measurement in the quarantine after the ozonation in seawater to specifically allow the bacterial deactivation, not to overwhelmingly produce TRO due to the residual ozone provided.

Bone-Like Apatite Formation on the Plasma Electrolytic Oxidation-Treated Ti-6Al-4V Alloy in Solution Containing Si and Mg Ions.

The bon-like apatite formation on the plasma electrolytic oxidation (PEO)-treated Ti-6Al-4V alloy in solution containing Si and Mg ions was studied using various experimental techniques. A Ti-6Al-4V ELI disk and implant was used as a substrate for PEO. A pulsed DC power supply was used to apply a potential of 280 V in the electrolyte for 3 min. To examine the bioactivity, the PEO films formed implant specimens were immersed in a simulated body fluid (SBF) for 12 h. PEO-treated surface has large micro-pores and small micro-pores, and 5 Mg/Si and 20 Mg/Si coated surfaces showed the more small micro-pores than that of CaP coated surface. The peaks of the anatase and the hydroxyapatite phases after SBF immersion shifted to the left as compared to before SBF immersion. Numbers of cells increased, as Mg content increased on the PEO treated surface. Bone-like apatite is well formed on the Mg and Si contained surface.

Manganese Coatings on Hydroxyapatite-Deposited Ti­29Nb­xHf Alloys After Nanomesh Formation.

The purpose of this study was to investigate manganese coatings on the hydroxyapatite-deposited Ti­29Nb­xHf alloy after nanomesh formation. The Ti alloy substrates for nanomesh formation were immersed in 5 M NaOH aqueous solution at 60 °C for 12 h. Electrochemical deposition of HA was carried out using cyclic voltammetry at 80 °C in 2.5 mM Ca(NO3)2 + 1.5 mM NH4H2PO4. The manganese coating was obtained by a radio frequency magnetron sputtering technique. The microstructure, composition, and phase structure of the coated alloys were examined by optical microscopy, field emission scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The microstructures of the Ti­29Nb­xHf alloys were changed from an α″ + ß phase to a ß phase, and needle-like structure to equiaxed structure with Hf content. The bulk surfaces of Ti­29Nb alloy were partially covered with a rod-like hydroxyapatite layer and exhibited rod-like and round edge shape. In contrast, the hydroxyapatite coating after mesh formation on the Ti­29Nb­15Hf alloy showed plate-like precipitates. Manganese coatings on the Ti­29Nb­xHf alloys with mesh formation exhibited rod-like particles at the tip of plate-like precipitates by RF-sputtering. The Ca/P ratios of the coatings were 1.4 and 1.68 without and with mesh formation, respectively.

Anti-IL-6 neutralizing antibody modulates blood-brain barrier function in the ovine fetus.

Impaired blood-brain barrier function represents an important component of hypoxic-ischemic brain injury in the perinatal period. Proinflammatory cytokines could contribute to ischemia-related blood-brain barrier dysfunction. IL-6 increases vascular endothelial cell monolayer permeability in vitro. However, contributions of IL-6 to blood-brain barrier abnormalities have not been examined in the immature brain in vivo. We generated pharmacologic quantities of ovine-specific neutralizing anti-IL-6 mAbs and systemically infused mAbs into fetal sheep at 126 days of gestation after exposure to brain ischemia. Anti-IL-6 mAbs were measured by ELISA in fetal plasma, cerebral cortex, and cerebrospinal fluid, blood-brain barrier permeability was quantified using the blood-to-brain transfer constant in brain regions, and IL-6, tight junction proteins, and plasmalemma vesicle protein (PLVAP) were detected by Western immunoblot. Anti-IL-6 mAb infusions resulted in increases in mAb (P < 0.05) in plasma, brain parenchyma, and cerebrospinal fluid and decreases in brain IL-6 protein. Twenty-four hours after ischemia, anti-IL-6 mAb infusions attenuated ischemia-related increases in blood-brain barrier permeability and modulated tight junction and PLVAP protein expression in fetal brain. We conclude that inhibiting the effects of IL-6 protein with systemic infusions of neutralizing antibodies attenuates ischemia-related increases in blood-brain barrier permeability by inhibiting IL-6 and modulates tight junction proteins after ischemia.

Comparison of anaerobic digestion of starch- and petro-based bioplastic under hydrogen-rich conditions.

To identify an economically viable waste management system for bioplastics, thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate) (PBAT) were anaerobically digested under hydrogen (H2)/carbon dioxide (CO2) and nitrogen (N2) gas-purged conditions to compare methane (CH4) production and biodegradation. Regardless of the type of bioplastics, CH4 production was consistently higher with H2/CO2 than with N2. The highest amount of CH4 was produced at 307.74 mL CH4/g volatile solids when TPS digested with H2/CO2. A stepwise increased in CH4 yield was observed, with a nominal initial increment followed by accelerated methanogenesis conversion as H2 was depleted. This may be attributed to a substantial shift in the microbial structure from hydrogenotrophic methanogen (Methanobacteriales and Methanomicrobiales) to heterotrophs (Spirochaetia). In contrast, no significant change was observed with PBAT, regardless of the type of purged gas. TPS was broken down into numerous derivatives, including volatile fatty acids. TPS produced more byproducts with H2/CO2 (i.e., 430) than with N2 (i.e., 320). In contrast, differential scanning calorimetry analysis on PBAT revealed an increase in crystallinity from 10.20 % to 12.31 % and 11.36 % in the H2/CO2- and N2-purged conditions, respectively, after 65 days of testing. PBAT surface modifications were characterized via Fourier transform infrared spectroscopy and scanning electron microscopy. The results suggest that the addition of H2/CO2 can enhance the CH4 yield and increase the breakdown rate of TPS more than that of PBAT. This study provides novel insights into the CH4 production potential of two bioplastics with different biodegradabilities in H2/CO2-mediated anaerobic digestion systems.

Sex Difference on Neurological Outcomes and Post-Cardiac Arrest Care in Out-of-Hospital Cardiac Arrest Patients Treated with Targeted Temperature Management: Post-Hoc Study of a Prospective, Multicenter, Observational Cohort Study.

Conflicting results regarding sex-based differences in the outcomes of out-of-hospital cardiac arrest (OHCA) patients have been reported. We aimed to evaluate the association between sex and neurological outcome as well as various in-hospital process in OHCA patients treated with targeted temperature management. We retrospectively analyzed a prospective registry data collected between October 2015 and December 2018. To evaluate the effect of sex on patient outcomes, we created various multivariable logistic regression models. When the results were adjusted using resuscitation variables and in-hospital variables, there was no significant difference (OR = 1.22, 95% CI: 0.85-1.74; OR = 1.13, 95 CI: 0.76-1.68, respectively). Regarding the in-hospital course, the daily total SOFA score was similar in both sexes, whereas cardiovascular scores were higher in women on days 2 and 3. The adjusted effect of sex was not associated with the clinician's decision to perform early cardiac interventions, except for those men that had more extracorporeal membrane oxygenation (OR = 2.51, 95% CI: 1.11-5.66). The findings seems that men had more favorable 6-month neurological outcomes. However, after adjusting for confounders, there was no difference between the sexes. The results regarding in-hospital course were similar in men and women.

Describing the longitudinal breakfast quality index trajectories in early childhood: results from Melbourne InFANT program.

BACKGROUND: Breakfast quality in early childhood remains understudied. This study describes the changes in breakfast quality index (BQI) (i.e. trajectory) in early childhood and assesses its associations with obesity outcomes. METHODS: Data from children who participated in the Melbourne InFANT Program were used (n = 328). The Melbourne InFANT Program was a 15-month early obesity prevention intervention conducted from 2008 to 2013. Dietary intakes at ages 1.5, 3.5 and 5.0 years were assessed using three parent-proxy reported 24 h recalls. A revised nine-item BQI tool developed based on Australian dietary recommendations for young children was used to calculate BQI scores. Group-based trajectory modelling identified BQI trajectory groups. Multivariable linear and logistic regression examined the associations between identified BQI trajectory groups and obesity outcomes at age 5 years. RESULTS: Mean BQI at ages 1.5, 3.5 and 5.0 years was 4.8, 4.8, 2.7 points, respectively. Two BQI trajectory groups were identified, and both showed a decline in BQI. The mean BQI of most children (74%) decreased from 5.0 to 4.0 points from ages 1.5 to 5.0 years (referred as "High BQI" group). The remaining children (26%) had a mean BQI of 4.8 and 1.2 points at age 1.5 and 5.0 years, respectively (referred as "Low BQI" group). The "Low BQI" group appeared to show higher risk of overweight (OR:1.30, 95% CI: 0.60, 2.81, P = 0.66) at age 5 years than the "High BQI" group. No difference in body mass index (BMI) z-score was found between the two groups. CONCLUSIONS: Two BQI trajectory groups were identified. Both groups showed a decline in breakfast quality from ages 1.5 to 5.0 years. Our study highlights the need for early health promotion interventions and strategies to improve and maintain breakfast quality across early childhood.

Ni-Ion-Chelating Strategy for Mitigating the Deterioration of Li-Ion Batteries with Nickel-Rich Cathodes.

Ni-rich cathodes are the most promising candidates for realizing high-energy-density Li-ion batteries. However, the high-valence Ni4+ ions formed in highly delithiated states are prone to reduction to lower valence states, such as Ni3+ and Ni2+ , which may cause lattice oxygen loss, cation mixing, and Ni ion dissolution. Further, LiPF6 , a key salt in commercialized electrolytes, undergoes hydrolysis to produce acidic compounds, which accelerate Ni-ion dissolution and the interfacial deterioration of the Ni-rich cathode. Dissolved Ni ions migrate and deposit on the surface of the graphite anode, causing continuous electrolyte decomposition and threatening battery safety by forming Li dendrites on the anode. Herein, 1,2-bis(diphenylphosphino)ethane (DPPE) chelates Ni ions dissolved from the Ni-rich cathode using bidentate phosphine moieties and alleviates LiPF6 hydrolysis via complexation with PF5 . Further, DPPE reduces the generation of corrosive HF and HPO2 F2 substantially compared to the amounts observed using trimethyl phosphite and tris(trimethylsilyl) phosphite, which are HF-scavenging additives. Li-ion cells with Ni-rich cathodes and graphite anodes containing DPPE exhibit remarkable discharge capacity retentions of 83.4%, with high Coulombic efficiencies of >99.99% after 300 cycles at 45 °C. The results of this study will promote the development of electrolyte additives.

Artificial neural network approach for acute poisoning mortality prediction in emergency departments.

OBJECTIVE: The number of deaths due to acute poisoning (AP) is on the increase. It is crucial to predict AP patient mortality to identify those requiring intensive care for providing appropriate patient care as well as preserving medical resources. The aim of this study is to predict the risk of in-hospital mortality associated with AP using an artificial neural network (ANN) model. METHODS: In this multicenter retrospective study, ANN and logistic regression models were constructed using the clinical and laboratory data of 1,304 patients seeking emergency treatment for AP. The ANN model was first trained on 912/1,304 (70%) randomly selected patients and then tested on the remaining 392/1,304 (30%). Receiver operating characteristic curve analysis was used to evaluate the mortality prediction of the two models. RESULTS: Age, endotracheal intubation status, and intensive care unit admission were significant predictors of mortality in patients with AP in the multivariate logistic regression model. The ANN model indicated age, Glasgow Coma Scale, intensive care unit admission, and endotracheal intubation status were critical factors among the 12 independent variables related to in-hospital mortality. The area under the receiver operating characteristic curve for mortality prediction was significantly higher in the ANN model compared to the logistic regression model. CONCLUSION: This study establishes that the ANN model could be a valuable tool for predicting the risk of death following AP. Thus, it may facilitate effective patient triage and improve the outcomes.

A case study on the correlation between radon and multiple geophysicochemical properties of soils in G island, Korea, and effects on the bacterial metabolic behaviors.

This study was conducted to assess the natural radiation intensity of radon observed from 'G' islands and its effects against Bacillus pumilus, predominantly found throughout the field survey. The physicochemical properties and microbial characteristics were simultaneously investigated and compared. From these studies, it was confirmed that the areal distribution of radon concentration varied from 920 Bq/m3 to 3367 Bq/m3 depending on the soil depth, lithology, or geophysicochemical properties (including pH, moisture content, and grain size) inherently subject to each location. Particularly, the slightly acidic (pH < 6) and low-fertility soil with a higher level of radon concentration exceeding 3000 Bq/m3 had a considerably low level of bacterial density. In contrast, the fertile soil of a relatively middle level of radon radioactivity revealed a much larger bacterial community density, dominated by Bacillus spp., Pseudomonas sp., Paenarthrobacter sp., and Microbacterium sp. Furthermore, the monitored metabolic activity and growth of Bacillus pumilus against the various radon exposure conditions clearly indicated that radon could be considered as the potential ecological risk to natural environmental habitats of microbial soil biota.

Biodegradation of micro-polyethylene particles by bacterial colonization of a mixed microbial consortium isolated from a landfill site.

In this study, we investigated the decomposition of micro-sized polyethylene (PE) by mesophilic mixed bacterial culture isolates obtained from a municipal landfill sediment. Among these, Bacillus sp. and Paenibacillus sp. were more specifically enriched in the non-carbonaceous nutrient medium (i.e., Basal medium) as they were the most dominant species when they were exposed to PE microplastics. They reduced the dry weight of particles (14.7% after 60 d) and the mean particle diameter (22.8% after 60 d; obtained by field-emission scanning electron microscopy analysis). In the gas chromatography-mass spectrometer analysis of biologically aged particles, the amount and types of organic contents eluted from the PE microplastics were far lower in the early decomposition phase; however, they increased in the later phase. Thermal gravimetric analysis showed that the aged particles had higher thermal stability at temperatures greater than 570 °C compared to the control, thereby suggesting that microplastics were degraded by enzymatic chain scission, which could in turn be ascribed to the greater refractory fractions of aged particles remaining at a high combustion temperature. It was further verified that PE particles could be biologically utilized as a sole carbon source and broken down during the test period.

Development of a keratinase activity assay using recombinant chicken feather keratin substrates.

Poultry feathers consist mainly of the protein keratin, which is rich in ß-pleated sheets and consequently resistant to proteolysis. Although many keratinases have been identified, the reasons for their substrate specificity towards ß-keratin remain unclear due to difficulties in preparing a soluble feather keratin substrate for use in activity assays. In the present study, we overexpressed Gallus gallus chromosomes 2 and 27 ß-keratin-encoding genes in Escherichia coli, purified denatured recombinant proteins by Ni2+ affinity chromatography, and refolded by stepwise dialysis to yield soluble keratins. To assess the keratinolytic activity, we compared the proteolytic activity of crude extracts from the feather- degrading bacterium Fervidobacterium islandicum AW-1 with proteinase K, trypsin, and papain using purified recombinant keratin and casein as substrates. All tested proteases showed strong proteolytic activities for casein, whereas only F. islandicum AW-1 crude extracts and proteinase K exhibited pronounced keratinolytic activity for the recombinant keratin. Moreover, LC-MS/MS analysis of keratin hydrolysates allowed us to predict the P1 sites of keratinolytic enzymes in the F. islandicum AW-1 extracts, thereby qualifying and quantifying the extent of keratinolysis. The soluble keratin-based assay has clear therapeutic and industrial potential for the development of a high-throughput screening system for proteases hydrolyzing disease-related protein aggregates, as well as mechanically resilient keratin-based polymers.

Inhibition of cell cycle progression via p27Kip1 upregulation and apoptosis induction by an ethanol extract of Rhus verniciflua Stokes in AGS gastric cancer cells.

Botanical preparations are widely used by patient with cancer in Korea, Japan and China. Rhus verniciflua Stokes (RVS) has traditionally been used as a medicinal ingredient for the therapy of stomach and uterine cancer. In this study, we showed that exposure to an ethanol extract of RVS (50 microg/ml) resulted in a synergistic inhibitory effect on cell growth in AGS cells. Growth inhibition was related with the inhibition of proliferation and induction of apoptosis. The extract induces G1-cell cycle arrest through the regulation of cyclins, the induction of p27Kip1, and decrease the CDK2 kinase activity. The upregulated p27Kip1 level is caused by protein stability increment by the reduction of Skp2, a key molecule related with p27Kip1 ubiquitination and degradation, and de novo protein synthesis. RVS extract induces apoptosis through the expression of Bax, poly(ADP-ribose) polymerase (PARP) and activation of caspase-3. RVS extract induces G1-cell cycle arrest via accumulation of p27Kip1 controlled by Skp2 reduction and apoptosis passing through an intrinsic pathway in human gastric cancer cells but not in normal cells, therefore we suggest that this extract could be a candidate medicine or compound for the development of novel class of anti-cancer drugs.