Suppressing Organic Bromine but Promoting Bromate: Is the Ultraviolet/Ozone Process a Double-Edged Sword for the Toxicity of Wastewater to Mammalian Cells?

Brominated byproducts and toxicity generation are critical issues for ozone application to wastewater containing bromide. This study demonstrated that ultraviolet/ozone (UV/O3, 100 mJ/cm2, 1 mg-O3/mg-DOC) reduced the cytotoxicity of wastewater from 14.2 mg of pentol/L produced by ozonation to 4.3 mg of pentol/L (1 mg/L bromide, pH 7.0). The genotoxicity was also reduced from 1.65 to 0.17 µg-4-NQO/L by UV/O3. Compared with that of O3 alone, adsorbable organic bromine was reduced from 25.8 to 5.3 µg/L by UV/O3, but bromate increased from 32.9 to 71.4 µg/L. The UV/O3 process enhanced the removal of pre-existing precursors (highly unsaturated and phenolic compounds and poly aromatic hydrocarbons), while new precursors were generated, yet the combined effect of UV/O3 on precursors did not result in a significant change in toxicity. Instead, UV radiation inhibited HOBr concentration through both rapid O3 decomposition to reduce HOBr production and decomposition of the formed HOBr, thus suppressing the AOBr formation. However, the hydroxyl radical-dominated pathway in UV/O3 led to a significant increase of bromate. Considering both organic bromine and bromate, the UV/O3 process effectively controlled both cytotoxicity and genotoxicity of wastewater to mammalian cells, even though an emphasis should be also placed on managing elevated bromate. Futhermore, other end points are needed to evaluate the toxicity outcomes of the UV/O3 process.

Assessing the Chemical-Free Oxidation of Trace Organic Chemicals by VUV/UV as an Alternative to Conventional UV/H2O2.

Low-pressure mercury lamps with high-purity quartz can emit both vacuum-UV (VUV, 185 nm) and UV (254 nm) and are commercially available and promising for eliminating recalcitrant organic pollutants. The feasibility of VUV/UV as a chemical-free oxidation process was verified and quantitatively assessed by the concept of H2O2 equivalence (EQH2O2), at which UV/H2O2 showed the same performance as VUV/UV for the degradation of trace organic contaminants (TOrCs). Although VUV showed superior H2O activation and oxidation performance, its performance highly varied as a function of light path length (Lp) in water, while that of UV/H2O2 proportionally decreased with decreasing H2O2 dose regardless of Lp. On increasing Lp from 1.0 to 3.0 cm, the EQH2O2 of VUV/UV decreased from 0.81 to 0.22 mM H2O2. Chloride and nitrate hardly influenced UV/H2O2, but they dramatically inhibited VUV/UV. The competitive absorbance of VUV by chloride and nitrate was verified as the main reason. The inhibitory effect was partially compensated by •OH formation from the propagation reactions of chloride or nitrate VUV photolysis, which was verified by kinetic modeling in Kintecus. In water with an Lp of 2.0 cm, the EQH2O2 of VUV/UV decreased from 0.43 to 0.17 mM (60.8% decrease) on increasing the chloride concentration from 0 to 15 mM and to 0.20 mM (53.5% decrease) at 4 mM nitrate. The results of this study provide a comprehensive understanding of VUV/UV oxidation in comparison to UV/H2O2, which underscores the suitability and efficiency of chemical-free oxidation with VUV/UV.

Applying machine learning random forest (RF) method in predicting the cement products with a co-processing of input materials: Optimizing the hyperparameters.

Co-processing recycled waste during cement production, i.e., using alternative materials such as secondary raw materials or secondary raw fuels, is widely practiced in developed countries. Alternative raw materials or fuels contain high concentrations of heavy metals and other hazardous chemicals, which might lead to the potential for dangerous heavy metals and hazardous chemicals to be transferred to clinker or cement products, resulting in exposure and emissions to people or the environment. Managing input materials and predicting which inputs affect the final concentration is essential to prevent potential hazards. We used the data of six heavy metals by input raw materials and input fuels of cement manufacturers in 2016-2017. The concentrations of Pb and Cu in cement were about 10-200 times and 4 to 200 times higher than other heavy metals (Cr, As, Cd, Hg), respectively. We profiled the influence of heavy metal concentration of each input material using the principal component analysis (PCA), which analyzed the leading causes of each heavy metal. The Random Forest (RF) ensemble model predicted cement heavy metal concentrations according to input materials. In the case of Cu, Cd, and Cr, the training performance showed R square values of 0.71, 0.71, and 0.92, respectively, as a result of predicting the cement heavy metal concentration according to the heavy metal concentration of each cement input material using the RF model, which is a machine learning model. The results of this study show that the RF model can be used to predict the amount and concentration of alternative raw materials and alternative fuels by controlling the concentration of heavy metals in cement through the concentration of heavy metals in the input materials.

Comparison of Trends in the Incidence of Traumatic Spinal Cord Injury in Daily Life, Automobile Accidents, and Industrial Accidents: A National Multi-Insurance Study in Korea.

BACKGROUND: To examine the incidence of traumatic spinal cord injury (TSCI) from all etiologies, we measured and compared the incidence of TSCI from three national or quasi-national databases in South Korea, namely, the National Health Insurance Service (NHIS), automobile insurance (AUI), and Industrial Accident Compensation Insurance (IACI). METHODS: We reviewed patients with TSCI reported in the NHIS database between 2009 and 2018, and in the AUI and IACI databases between 2014 and 2018. TSCI patients were defined as those first admitted to the hospital with a diagnosis of TSCI according to the International Classification of Diseases (10th revision) criteria. Age-adjusted incidence was calculated using direct standardization using the 2005 South Korean population or the 2000 US population as the standard population. The annual percentage changes (APC) of TSCI incidence were calculated. The Cochrane-Armitage trend test was performed according to the injured body region. RESULTS: In the NHIS database, age-adjusted TSCI incidence using the Korean standard population increased significantly from 2009 to 2018 (from 33.73 per million in 2009 to 38.14 per million in 2018, APC = 1.2%, P = 0.014). Contrarily, age-adjusted incidence in the AUI database significantly decreased from 13.88 per million in 2014 to 11.57 per million in 2018 (APC = - 5.1%, P = 0.009). In the IACI database, the age-adjusted incidence showed no significant difference, while crude incidence showed a significant increase (from 22.02 per million in 2014 to 28.92 per million in 2018, APC = 6.1%, P = 0.038). According to the age group, all the three databases showed high incidences of TSCI in those in their 60s and 70s or older. Among those in their 70s or older, the incidence of TSCI increased dramatically in the NHIS and IACI databases, while no significant trend was found in AUI database. In 2018, the number of TSCI patients was the highest among those over 70 years of age in the NHIS, whereas among those in their 50s were the highest in both AUI and IACI. The proportion of patients with cervical spinal cord injury was the most common in all these databases. CONCLUSIONS: The differences in trends in the incidence of TSCI may be due to the different etiologies and different characteristics of subjects depending on insurance type. These results imply the need for tailored medical strategies for the different injury mechanisms represented by three national insurance services in South Korea.

Satisfying medical and rehabilitation needs positively influences returning to work after a work-related injury: an analysis of national panel data from 2018 to 2019.

BACKGROUND: This study examined how meeting the medical needs of injured workers after initial treatment may affect their return to work, using data from the Panel Study of Workers' Compensation Insurance. METHODS: This study was designed as a longitudinal study, which used data from the second-year, follow-up survey conducted in the secondary cohort of the Panel Study of Workers' Compensation Insurance. The odds ratio (OR) and 95% confidence interval were estimated through binomial and multinomial logistic regression analyses to examine the effects of unmet medical needs on workers' return to original work and return to work overall (including reemployment). RESULTS: The returned to original work OR of workers whose rehabilitation needs were met was 1.35 (1.12-1.63) while the return to work OR was 1.20 (1.03-1.41). The returned to original work OR of workers whose medical needs were met was 1.64 (1.18-2.27) while the return to work OR was 1.39 (1.07-1.80). In terms of disability rating, the return to work ORs of workers with mild disabilities whose medical/rehabilitation needs were not met and those of workers without disabilities were 1.71 (1.17-2.49) and 1.97 (1.27-3.08), respectively. In the case of regular/temporary workers, the returned-to-work ORs of workers whose medical/rehabilitation needs were not met were 1.54 (1.12-2.13) and 1.27 (1.03-1.56), respectively. CONCLUSIONS: For workers who sustained work-related injuries, providing medical accessibility and meeting rehabilitation needs were found to be important predictors of return to work after initial treatment.

Application of material flow analysis for plastic waste management in the Republic of Korea.

The indiscriminate use of plastics and careless management of plastic waste have caused serious environmental challenges globally. The Republic of Korea (ROK) aims to address the issue by reducing plastic waste generation by up to 50%, and increasing recycling rate by up to 70%, by 2030. To determine the status and future directions for plastic waste management in the ROK, the present study undertook two tasks: (i) a material flow analysis of plastic waste material from industrial sectors to assess the current status of plastic waste recycling and treatment, (ii) an analysis of the material flow of plastic waste based on the "Waste Classification Code." According to the findings, 6.202 million metric tons of plastic waste were generated in 2018, out of which 69%, 25%, and 0.5% was recycled, incinerated, and landfilled, respectively. The recycling rate of synthetic resin waste, which accounts for 96% of synthetic waste polymers discharged in the industrial sector, was 69%, which is a very high rate. However, the closed-loop recycling rate was only 33%. Therefore, the system of management of synthetic resin waste discharge without classification of raw materials should be improved to increase the closed-loop recycling rate of synthetic waste polymers. Furthermore, to increase the closed-loop recycling rate, we suggest the subdivision of synthetic resin waste (51-03-01) in plastic waste classification to improve the discharge separation system, which has been mismanaged. Furthermore, we suggest the formulation of a new management strategy for plastic waste, in accordance with those of other hazardous substances, as regulated by the Waste Control Act.

Potential risk of exposure to heavy metals from co-processing of secondary wastes in the Republic of Korea.

The co-processing of secondary wastes during ordinary Portland cement (OPC) can result in high heavy metal concentrations in OPC products. However, earlier studies have not evaluated the concentrations of heavy metals (HMs) in OPC as a function of secondary input materials. Further, the health risk assessment (HRA) model has, thus far, has not been employed to assess the potential health risks associated with secondary raw materials and secondary fuels in OPC. Hence, to address these knowledge gaps, herein, monthly data for six HMs in the input materials and fuels from seven OPC manufacturers in the Republic of Korea were analyzed and modeled. Pb and Cu concentrations were found to be approximately 10-200 and 4-200 times higher than those of the other HMs, respectively. Furthermore, maximum Pb and Cu concentrations were 2-3 and 2-5 times higher than those reported in other countries, respectively. The quantity of input material had a significant influence on the observed patterns, and secondary raw materials, secondary additives, and secondary fuels were also determined to be important. Based on HRA assessment, although the risk levels were within permissible ranges, carcinogenic hazards attributable to Cr and Pb were not negligible. The results can aid in informed decision making and in implementing effective measures for managing risks associated with HMs in the OPC industry, thereby ameliorating threats to human health and environment.

Proteomic Analysis Reveals Distinct Metabolic Differences Between Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF) Grown Macrophages Derived from Murine Bone Marrow Cells.

Macrophages are crucial in controlling infectious agents and tissue homeostasis. Macrophages require a wide range of functional capabilities in order to fulfill distinct roles in our body, one being rapid and robust immune responses. To gain insight into macrophage plasticity and the key regulatory protein networks governing their specific functions, we performed quantitative analyses of the proteome and phosphoproteome of murine primary GM-CSF and M-CSF grown bone marrow derived macrophages (GM-BMMs and M-BMMs, respectively) using the latest isobaric tag based tandem mass tag (TMT) labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Strikingly, metabolic processes emerged as a major difference between these macrophages. Specifically, GM-BMMs show significant enrichment of proteins involving glycolysis, the mevalonate pathway, and nitrogen compound biosynthesis. This evidence of enhanced glycolytic capability in GM-BMMs is particularly significant regarding their pro-inflammatory responses, because increased production of cytokines upon LPS stimulation in GM-BMMs depends on their acute glycolytic capacity. In contrast, M-BMMs up-regulate proteins involved in endocytosis, which correlates with a tendency toward homeostatic functions such as scavenging cellular debris. Together, our data describes a proteomic network that underlies the pro-inflammatory actions of GM-BMMs as well as the homeostatic functions of M-BMMs.

Antibacterial efficacy and osteogenic potential of mineral trioxide aggregate-based retrograde filling material incorporated with silver nanoparticle and calcium fluoride.

Background/purpose: The retrograde filling material, particularly mineral trioxide aggregate (MTA) employed in apicoectomy, should possess high antibacterial efficacy and osteogenic potential. We evaluated the antibacterial efficacy, biocompatibility, and osteogenic potential following the addition of silver nanoparticles (AgNPs) and calcium fluoride (CaF2) in retrograde filling material of MTA. Materials and methods: MTA was mixed with four different solvents. Group 1 (G1): distilled water, Group 2 (G2): 50 ppm AgNPs, Group 3 (G3): 1 wt% CaF2, and Group 4 (G4): 50 ppm AgNPs and 1 wt% CaF2. The pH variation of each group was monitored, while the surface roughness was measured. The antibacterial efficacy against Enterococcus faecalis (E. faecalis) and the viability of murine pre-osteoblast (MC3T3) were evaluated for each group using colorimetric assays. The gene expression levels of osteogenic potential marker (OCN, ALPL, and RUNX2) in MC3T3 cells for each group were quantified using real-time-qPCR. Statistical analysis was performed at α = 0.05 level of significance. Results: When comparing the levels of antibacterial efficacy, the order of effectiveness was G4>G2>G3>G1 (P < 0.05). In the cell viability test, owing to MTA-eluted growth medium having a positive effect on MC3T3 cell proliferation, G1-4 exhibited a statistically increased cell viability compared to the control (P < 0.05). However, G2-4 did not result in a statistically significant difference when compared to G1 (P < 0.05). Moreover, G4 exhibited the highest gene expression among the four groups (P < 0.05). Conclusion: The addition of AgNPs and CaF2 to MTA could be a promising option for use as a new retrograde filling material.

Thermophysical properties and bonding with composite resin of premixed mineral trioxide aggregate for use as base material.

Dental bases require low thermal conductivity and good mechanical properties, such as bonding with composite resins. This study aims to elucidate the physicochemical properties of premixed mineral trioxide aggregate (MTA) for its suitability as a dental base and to explore the optimal adhesive strategy with composite resin. The thermal conductivity and compressive strength of this premixed MTA are 0.12 W/(m•K) and 93.76 MPa, respectively, Which are deemed adequate for its application as dental base. When bonded to composite resin, the use of 37% phosphoric acid etching before applying the Clearfil SE bond significantly reduced the bonding strength between composite resin and premixed MTA. This was because the compressive strength and Vickers hardness of premixed MTA decreased, and tricalcium silicate was dissolved from the surface during acid etching. Therefore, it is recommended to avoid using 37% phosphoric acid etching when bonding premixed MTA and composite resin as a dental base.

Mineral trioxide aggregate in membrane form as a barrier membrane in guided bone regeneration.

Background/purpose: In the field of conservative dentistry and endodontics, mineral trioxide aggregate (MTA), commonly used, possesses advantages such as biocompatibility, antimicrobial properties and osteogenic potential. This study investigated the feasibility of utilizing membrane form mineral trioxide aggregate (MTA) as a barrier membrane in guided bone regeneration (GBR) procedures. Materials and methods: Membranes were electrospun from three different formulations: 15 w/v% Polycaprolactone (PCL), 13 w/v% PCL + 2 w/v% MTA (2MTA), and 11 w/v% PCL + 4 w/v% MTA (4MTA). Physicochemical and mechanical properties of the electrospun membrane were compared, encompassing parameters such as surface morphology, fiber diameter distribution, chemical composition, phase identification, tensile stress, pH variation, and water contact angle. Moreover, the antimicrobial properties against of the electrospun membranes were assessed through direct exposure to streptococcus aureus (S. aureus) and candida albicans (C. albicans). Additionally, on the 7th day, biocompatibility and cell attachment were investigated with respect to L929 (fibroblast) and MC3T3 (pre-osteoblast) cells. Inhibition of L929 cell infiltration and the expression of osteogenic related genes including osteocalcin (OCN), alkaline phosphatase (ALP), and runt related transcription factor 2 (RUNX2) in MC3T3 cells on 7th and 14th days were also investigated. Results: PCL, 2MTA, and 4MTA exhibited no statistically differences in fiber diameter distribution and tensile stress. However, as the MTA content increased, wettability and pH also increased. Due to the elevated pH, 4MTA demonstrated the lowest viability S.aureus and C.albicans. All membranes were highly biocompatibility and promoted cell attachment, while effectively preventing L929 cell infiltration. Lastly 4MTA showed increase in OCN, ALP, and RUNX2 expression on both 7th and 14th day. Conclusion: The membrane form MTA possessed characteristics essential for a novel barrier membrane.

Suppression of photoreactivation of E. coli by excimer far-UV light (222 nm) via damage to multiple targets.

Low-pressure mercury lamps emitting at 254 nm (UV254) are used widely for disinfection. However, subsequent exposure to visible light results in photoreactivation of treated bacteria. This study employed a krypton chloride excimer lamp emitting at 222 nm (UV222) to inactivate E. coli. UV222 and UV254 treatment had similar E. coli-inactivation kinetics. Upon subsequent irradiation with visible light, E. coli inactivated by UV254 was reactivated from 2.71-log to 4.75-log, whereas E. coli inactivated by UV222 showed negligible photoreactivation. UV222 treatment irreversibly broke DNA strands in the bacterium, whereas UV254 treatment primarily formed nucleobase dimers. Additionally, UV222 treatment caused cell membrane damage, resulting in wizened, pitted cells and permeability changes. The damage to the cell membrane was mainly due to the photolysis of proteins and lipids by UV222. Furthermore, the photolysis of proteins by UV222 destroyed enzymes, which blocked photoreactivation and dark repair. The multiple damages can be further evidenced by 4.0-61.1 times higher quantum yield in the photolysis of nucleobases and amino acids for UV222 than UV254. This study demonstrates that UV222 treatment damages multiple sites in bacteria, leading to their inactivation. Employing UV222 treatment as an alternative to UV254 could be viable for inhibiting microorganism photoreactivation in water and wastewater.

Ozone, hydrogen peroxide, and peroxymonosulfate disinfection of MS2 coliphage in water.

The control of viruses in water is critical to preventing the spread of infectious viral diseases. Many oxidants can inactivate viruses, and this study aims to systematically compare the disinfection effects of ozone (O3), peroxymonosulfate (PMS), and hydrogen peroxide (H2O2) on MS2 coliphage. The effects of oxidant dose and contact time on disinfection were explored, as were the disinfection effects of three oxidizing agents in secondary effluent. The 4-log inactivation of MS2 coliphage required 0.05 mM O3, 0.5 mM PMS, or 25 mM H2O2 with a contact time of 30 min. All three oxidants achieved at least 4-log disinfection within 30 min, and O3 required only 0.5 min. In secondary effluent, all three oxidants also achieved 4-log inactivation of MS2 coliphage. Excitation-emission matrix (EEM) results indicate that all three oxidants removed dissolved organic matter synchronously and O3 oxidized dissolved organic matter more thoroughly while maintaining disinfection efficacy. Considering the criteria of oxidant dose, contact time, and disinfection efficacy in secondary effluent, O3 is the best choice for MS2 coliphage disinfection among the three oxidants.

Floating electrode-dielectric barrier discharge-based plasma promotes skin regeneration in a full-thickness skin defect mouse model.

Wound healing involves a complex and dynamic interplay among various cell types, cytokines, and growth factors. Macrophages and transforming growth factor-ß1 (TGF-ß1) play an essential role in different phases of wound healing. Cold atmospheric plasma has a wide range of applications in the treatment of chronic wounds. Hence, we aimed to investigate the safety and efficacy of a custom-made plasma device in a full-thickness skin defect mouse model. Here, we investigated the wound tissue on days 6 and 12 using histology, qPCR, and western blotting. During the inflammation phase of wound repair, macrophages play an important role in the onset and resolution of inflammation, showing decreased F4/80 on day 6 of plasma treatment and increased TGF-ß1 levels. The plasma-treated group showed better epidermal epithelialization, dermal fibrosis, collagen maturation, and reduced inflammation than the control group. Our findings revealed that floating electrode-dielectric barrier discharge (FE-DBD)-based atmospheric-pressure plasma promoted significantly faster wound healing in the plasma-treated group than that in the control group with untreated wounds. Hence, plasma treatment accelerated wound healing processes without noticeable side effects and suppressed pro-inflammatory genes, suggesting that FE-DBD-based plasma could be a potential therapeutic option for treating various wounds.

Efficient wastewater disinfection using a novel microwave discharge electrodeless ultraviolet system with ozone at an ultra-low dose.

Microwave discharge electrodeless lamp (MDEL) is a novel ultraviolet (UV) light source. Synergistic disinfection using UV light emitted by MDEL (MWUV) coupled with ozone (O3) at an ultra-low dose was investigated. Escherichia coli and Bacillus subtilis were deactivated more effectively by MWUV/O3 than by either MWUV or O3 alone. MWUV/O3 treatment using an O3 concentration of 0.4 mg/L gave an E. coli inactivation rate of 5.52 log. The photoreactivation degree and rate of E. coli were lower after inactivation by MWUV/O3 treatment than after MWUV treatment alone. The maximum photoreactivation rates after the MWUV/O3 and MWUV treatments were 2.90% and 16.08%, respectively. MWUV/O3 disinfection also inhibited dark resurrection of E. coli and gave a maximum dark resurrection rate of 0.0036%. Electron paramagnetic resonance spectroscopy indicated that more hydroxyl radicals were generated during MWUV/O3 treatment. Scanning electron microscopy and laser confocal scanning microscopy observations indicated that O3 played a key role in breaking down the cell structure. MWUV/O3 treatment gave a good disinfection effect on fecal coliform bacteria in actual domestic wastewater. The results indicated that inactivation of bacteria can be more effectively achieved by MWUV treatment with O3.

Association Between Initiation of Rehabilitation and Length of Hospital Stay for Workers with Moderate to Severe Work-Related Traumatic Brain Injury.

Background: In workers with moderate to severe work-related traumatic brain injury (wrTBI), this study aimed to investigate the effect of the timing of rehabilitation therapy initiation on the length of hospital stay and the factors that can influence this timing. Methods: We used data obtained from the Republic of Korea's nationwide Workers' Compensation Insurance. In the Republic of Korea, between the years 2010 and 2019, a total of 26,324 workers filed a claim for compensation for moderate to severe wrTBI. Multiple regression modeling was performed to compare the length of hospital stay according to the timing of rehabilitation therapy initiation following wrTBI. According to the timing of the initiation of rehabilitation therapy following TBI, the proportions of healthcare institutions that provided medical care during each admission step were compared. Results: The length of hospital stay for workers who started rehabilitation therapy within 90 days was significantly shorter than that for workers who started rehabilitationment were first admitted to tertiary hospitals. Approximately 39% of patients who received delayed rehabilitation treatment were first admitted to general hospitals, and 28.5% were first admitted to primary hospitals. Conclusions: Our findings demonstrate the importance of early rehabilitation initiation and that the type of healthcare institution that the patient is first admitted to after wrTBI may influence the timing of rehabilitation initiation. The results of this study also emphasize the need to establish a Worker's Compensation Insurance-specialized rehabilitation healthcare delivery system.

Epidemiology of Work-Related Traumatic Spinal Cord Injury: An Analysis of Workers' Compensation Claims in Korea, 2011-2019.

OBJECTIVE: We aimed to identify the incidence and burden of work-related traumatic spinal cord injury (wrTSCI) in Korea in the 10-year period from 2010 to 2019. METHODS: We used nationwide workers' compensation insurance data. The study population comprised industrially injured workers with TSCI diagnosis codes. The annual incidence of wrTSCI (number per million workers) was calculated. RESULTS: The mean annual incidence of wrTSCI was 22.8/1,000,000 (95% confidence interval, 20.5 to 25.0), and the mean total cost per claim was 231.40 million KRW. The incidence of TSCI in the cervical region was the highest (13.1/1,000,000; 95% confidence interval, 11.4 to 14.9), and most cases were in the construction industry (47.3%). CONCLUSION: These findings can help identify specific at-risk groups and facilitate the development of prevention strategies.

Frequency and Cost of Claims by Injury Type From the Korea Workers' Compensation Insurance Between 2016 and 2019.

OBJECTIVE: This study aimed to examine the frequency of worker injuries by affected body part(s) and the associated costs. Methods : We performed a secondary analysis of national workers' compensation claims data from the Korean workers' compensation insurance. The main outcome measures were frequency and cost of claims by injury type. Results : Multiple injuries were ranked as the highest injury type in the number of annual claims and percentage of the total cost/total medical cost. Hand/wrist/finger was the most common single-injury type. The frequency of injury type and the cost amount payable as a percentage of the total cost were the highest for multiple injuries, hand/wrist/finger injuries, and knee/lower leg injuries. Conclusions : Regarding frequency and costs, hand/wrist/finger injuries were highest in cost, by single-injury type. Therefore, these injuries should be recognized as intervention targets.

Proteomic discovery of prognostic protein biomarkers for persisting problems after mild traumatic brain injury.

Some individuals with mild traumatic brain injury (mTBI), also known as concussion, have neuropsychiatric and physical problems that last longer than a few months. Symptoms following mTBI are not only impacted by the kind and severity of the injury but also by the post-injury experience and the individual's responses to it, making the persistence of mTBI particularly difficult to predict. We aimed to identify prognostic blood-based protein biomarkers predicting 6-month outcomes, in light of the clinical course after the injury, in a longitudinal mTBI cohort (N = 42). Among 420 target proteins quantified by multiple-reaction monitoring-mass spectrometry assays of blood samples, 31, 43, and 15 proteins were significantly associated with the poor recovery of neuropsychological symptoms at < 72 h, 1 week, and 1 month after the injury, respectively. Sequential associations among clinical assessments (depressive symptoms and cognitive function) affecting the 6-month outcomes were evaluated. Then, candidate biomarker proteins indirectly affecting the outcome via neuropsychological symptoms were identified. Using the identified proteins, prognostic models that can predict the 6-month outcome of mTBI were developed. These protein biomarkers established in the context of the clinical course of mTBI may have potential for clinical application.

Vacuum ultraviolet irradiation for reduction of the toxicity of wastewater towards mammalian cells: Removal mechanism, changes in organic compounds, and toxicity alternatives.

Vacuum ultraviolet (VUV, 185 + 254 nm) irradiation performs well for oxidation of model pollutants. However, oxidation of pollutants does not necessarily lead to a reduction in toxicity. Currently, a comprehensive understanding of the effect of VUV irradiation on the toxicity of real wastewater is still lacking. In this study, the influence of VUV irradiation on the toxicity of secondary effluents to Chinese hamster ovary (CHO) cells was investigated. The induction units of endogenous reactive oxygen species (ROS) and 8-hydroxyguanosine (8-OHdG) in cells continuously decreased with prolonged irradiation time. After 36 min of irradiation, the cytotoxicity and the genotoxicity of the secondary effluents were reduced by 57%-63% and 56%-61%, respectively. The UV (254 nm), •OH, and other substances generated during the VUV irradiation directly drive toxicity changes of wastewater. The contribution of •OH generated during VUV irradiation to the reductions in cytotoxicity and genotoxicity of the secondary effluents reached 72%-78% and 77%-84%, respectively. Hydroxyl radicals generated during VUV irradiation played an important role in the detoxification. The relative signal intensity of dissolved organic carbon (DOC) > 500 Da was partially removed, whereas that of DOC < 500 Da was small changed. Since the content of DOC > 500 Da in the samples was much lower than that of DOC < 500 Da, the removal of total DOC was only 15.8%-20.0% after 36 min of irradiation. The UV254 values and the fluorescence intensity values for different molecular weights (MWs) were all reduced effectively by VUV irradiation. Electron-rich organic compounds of all MWs were all sensitive to VUV irradiation. There were mono-linear relationships between changes in chemical indexes and changes in cytotoxicity or genotoxicity. The total fluorescence intensity (Ex: 220-420 nm, Em: 280-560 nm) was identified as the best indicator of the reduction in toxicity.