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Volatile organic compounds (VOCs), with their ubiquitous presence across numerous global industries, pose multifaceted challenges, influencing air pollution and health outcomes. In response, countries such as the United States and Canada have implemented fenceline monitoring systems, enabling real-time tracking of organic solvents, including benzene. Initially, this focus was predominantly placed on the petroleum refining industry, but it has gradually been broadening. This investigation seeks to identify and analyze the specific VOCs produced in the tire manufacturing sector by utilizing both active and passive monitoring methodologies. The findings of the present study aim to recommend prioritized reduction strategies for specific VOCs. Percentage means the ratio of VOCs detected at the research site. At research target facility A, active monitoring demonstrated the presence of Methylene chloride (20.7%) and Carbon tetrachloride (15.3%), whereas passive monitoring identified Carbon tetrachloride (43.4%) and m,p-Xylene (20.8%). After converting these substances to their equivalent concentrations, we found a noteworthy correlation between the active and passive methodologies. At research target facility B, active monitoring detected n-Pentane (45.5%) and Isoprene (11.4%), while passive monitoring revealed Toluene (21.3%) and iso-Hexane (15.8%). Interestingly, even at sites like warehouses and test tracks where VOC concentrations were projected to be low, we observed VOC levels comparable to those in process areas. This underlines the fact that the dispersal of VOCs is considerably influenced by wind direction and speed. Specifically, in the tire manufacturing industry, emissions of Xylene and 3-Methylhexane, both having high photochemical ozone creation potential (POCP), contribute significantly to air pollution. However, the overall detection concentration in the tire manufacturing industry was detected at a low concentration of less than 2 μg/m3. This is less than 9 μg/m3, which is the standard for benzene, which has strong carcinogenicity regulations. This suggests that additional research is needed on synthetic rubber manufacturing rather than tire manufacturing.

Background: According to the previous studies, the work-related accident rate decreased in Korea after the introduction of occupational health and safety management system (OHSMS), but there were several disasters in Korea such as subway worker's death at Guui station in 2016 and the Taean thermal power plant accident in 2018, which escalated the social demand for safety. In 2018, OHSMS became an international standard, as ISO45001 was announced. Methods: A survey was conducted to research the implementation status of OHSMS and changes in people's perception, and the results were compared with those of a past survey. Results: Enhanced social demand and various stakeholders' (not only buyer) needs, and social responsibility are perceived as the motivation for the introduction of OHSMS rather than legal compliance or customer demand. In the questionnaire about problems with the implementation of OHSMS, the factors with higher response rate in 2018 than 2004 were “excessive cost” and “complicated documentation management.” In the questionnaire about how to promote OHSMS in organizations, most people answered “reduction of workers' compensation insurance rate” in 2004, but most people answered “exemption from health and safety supervision” in 2018. Conclusion: For the effective implementation of ISO45001, emphasis is placed on social demand, training to recognize health and safety as a part of management, and the reduction of certification and consulting costs to promote the introduction of OHSMS. Incentives such as insurance premium cuts and exemptions from health and safety supervision are needed.

The petroleum refining industry emits various volatile organic compounds (VOCs), including high-volatility benzene, which can have a significant impact on the local community. To address this issue, the US Environmental Protection Agency (EPA) has implemented a fenceline monitoring system to ensure that benzene concentrations at the fenceline do not exceed 9 μg/m3. However, there are various types of VOCs, and some with high potential atmospheric oxidation (POCP) values, that may cause secondary air pollution. This study found that both study sites exceeded the action level of benzene (9 μg/m3), and the locations where the level was exceeded were close to the crude distillation unit (CDU) (max concentration 34.07 μg/m3). Additionally, a significant amount of xylene with a high POCP was also released. The xylene emission rate of study site A was 27.71%, and the xylene emission rate of study site B was 46.75%. Therefore, it is necessary to reduce both high-volatility benzene and high-POCP xylene. In various industries that use organic solvents, it is important to prioritize VOCs for continuous measurement and analysis and to establish reduction strategies.

Metal–organic framework glasses have emerged as a new family of melt-quenched glass, but have yet to display the accessible porosity of their crystalline counterparts. Here, Bennett and colleagues report that glasses derived from ZIF-76 parent materials possess 4 – 8 Å pores and exhibit reversible gas adsorption.

Background: The study was conducted to investigate the current status of the occupational health and safety management system (OHSMS) in the construction industry and the effect of OHSMS on accident rates. Differences of awareness levels on safety issues among site general managers and occupational health and safety (OHS) managers are identified through surveys. Methods: The accident rates for the OHSMS-certified construction companies from 2006 to 2011, when the construction OHSMS became widely available, were analyzed to understand the effect of OHSMS on the work-related injury rates in the construction industry. The Korea Occupational Safety and Health Agency 18001 is the certification to these companies performing OHSMS in South Korea. The questionnaire was created to analyze the differences of OHSMS awareness between site general managers and OHS managers of construction companies. Results: The implementation of OHSMS among the top 100 construction companies in South Korea shows that the accident rate decreased by 67% and the fatal accident rate decreased by 10.3% during the period from 2006 to 2011. The survey in this study shows different OHSMS awareness levels between site general managers and OHS managers. The differences were motivation for developing OHSMS, external support needed for implementing OHSMS, problems and effectiveness of implementing OHSMS. Conclusion: Both work-related accident and fatal accident rates were found to be significantly reduced by implementing OHSMS in this study. The differences of OHSMS awareness between site general managers and OHS managers were identified through a survey. The effect of these differences on safety and other benefits warrants further research with proper data collection.

Neurotrophins render neurons highly vulnerable to certain injuries. We examined the possibility that NT-4/5 would enhance free radical neurotoxicity in vivo as well as in vitro. Striatal neurons exposed to 10 μM Fe2+ or 1 mM l-buthionine-[S, R]-sulfoximine (BSO) underwent mild degeneration within 24 h. With concurrent addition of 10–100 ng/ml NT-4/5, neuronal death following exposure to Fe2+ or BSO was significantly increased and suppressed by addition of 100 μM trolox, an antioxidant. In the adult brain, the intrastriatal injections of 20 nmol Fe2+ revealed features of neuronal necrosis such as swelling cell body and mitochondria, fenestration of plasma membrane prior to nuclear membrane, and scattering condensation of nuclear chromatin. Cotreatment with 1.8 μg NT-4/5 augmented the striatal damage 24 h following the injections of Fe2+. This study implies that free radicals produce necrotic degeneration in vivo as well as in vitro that becomes more sensitive in the presence of neurotrophins.

BACKGROUND: Approximately 15% of the United States population suffers from chronic kidney disease (CKD), often demonstrating an associated impairment in wound healing. This study outlines the development of a surgical murine model of CKD in order to investigate the mechanisms underlying this impairment. METHODS: CKD was induced in mice by partial cauterization of one kidney cortex and contralateral nephrectomy, modifying a previously published technique. After a minimum of 6-weeks, splinted, dorsal excisional wounds were created to permit assessment of wound healing parameters. Wounds were harvested on postoperative days (POD) 0, 3, 7, and 14 for histological, immunofluorescent, and quantitative PCR (qPCR). RESULTS: CKD mice exhibited deranged blood chemistry and hematology profiles, including profound uremia and anemia. Significant decreases in re-epithelialization and granulation tissue deposition rates were found in uremic mice wounds relative to controls. On immunofluorescent analysis, uremic mice demonstrated significant reductions in cellular proliferation (BrdU) and angiogenesis (CD31), with a concurrent increase in inflammation (CD45) as compared to controls. CKD mice also displayed differential expression of wound healing-related genes (VEGF, IL-1β, eNOS, iNOS) on qPCR. CONCLUSIONS: These findings represent the first reported investigation of cutaneous healing in a CKD animal model. Ongoing studies of this significantly delayed wound healing phenotype include the establishment of renal failure model in diabetic strains to study the combined effects of CKD and diabetes.

IntroductionThe recent literature suggests that chronic wound biofilms often consist of multiple bacterial species. However, without appropriate in vivo, polybacterial biofilm models, our understanding of these complex infections remains limited. We evaluate and compare the effect of single- and mixed-species biofilm infections on host wound healing dynamics using a quantitative, in vivo, rabbit ear model.MethodsSix-mm dermal punch wounds in New Zealand rabbit ears were inoculated with Staphylococcus aureus strain UAMS-1, Pseudomonas aeruginosa strain PAO1, or both, totaling 10/6 colony-forming units/wound. Bacterial proliferation and maintenance in vivo were done using procedures from our previously published model. Wounds were harvested for histological measurement of wound healing, viable bacterial counts using selective media, or inflammatory cytokine (IL-1β, TNF-α) expression via quantitative reverse-transcription PCR. Biofilm structure was studied using scanning electron microscopy (SEM). For comparison, biofilm deficient mutant UAMS-929 replaced strain UAMS-1 in some mixed-species infections.ResultsBacterial counts verified the presence of both strains UAMS-1 and PAO1 in polybacterial wounds. Over time, strain PAO1 became predominant (pConclusionsThis study reveals that mixed-species biofilms have a greater impact on wound healing dynamics than their monospecies counterparts. The increased virulence of polybacterial biofilm appears dependent on the combined pathogenicity of each species, verified using a mutant strain. These data suggest that individual bacterial species can interact synergistically within a single biofilm structure.

In some countries with high population densities including Korea, chemical plants are densely distributed, and strict regulations are imposed. According to the Chemical Control Act, one gas detector must be installed every 10 m indoors and 20 m outdoors around a facility. However, the diffusion of chemicals should be evaluated based on area rather than perimeter. In the US and EU, gas detector locations are selected through chemical accident modeling. Here, we evaluated the feasibility of gas detector installation standards in the Chemicals Control Act by comparing highly volatile and toxic chemicals with sulfuric acid (relatively low volatility). Consequently, we suggested an appropriate installation location and number of gas detectors for initial countermeasures. For nitric acid, hydrochloric acid, and hydrofluoric acid, there was a difference in the number of detectors recommended via modeling and the number of detectors legally required. For the mezzanine design, four gas detectors should be installed on each floor in a 5‐story building; however, the modeling results showed that installing one was sufficient. For sulfuric acid with low vapor pressure, it is equitable to install a leak detector rather than a gas detector. Overall, regulations should be continuously evaluated for the response and prevention of chemical accidents. [ABSTRACT FROM AUTHOR]

Abstract Individual variability exists in parkinsonian motor symptoms despite a similar degree of nigrostriatal dopamine depletion in Parkinson’s disease (PD), called motor reserve. We enrolled 397 patients newly diagnosed with PD who underwent dual-phase 18F-FP-CIT PET upon initial assessment. Individual motor reserve was estimated based on initial parkinsonian motor symptoms and striatal dopamine transporter availability using a residual model. Patients with low motor reserve (the lowest quartile group, n = 100) exhibited decreased uptake in the occipital region compared to those with high motor reserve (the highest quartile group, n = 100) on early-phase 18F-FP-CIT PET images. Patients with high motor reserve had a lower risk of conversion to dementia than the those with low motor reserve, whereas the effect of PD groups on the risk of dementia conversion was not mediated by occipital hypoperfusion. These findings suggest that cerebral hypoperfusion in the occipital region is associated with low motor reserve in patients with PD.

Abstract Objective Osteoarthritis (OA) is a degenerative joint disease caused by the breakdown of joint cartilage and adjacent bone. Joint injury, being overweight, differences in leg length, high levels of joint stress, abnormal joint or limb development, and inherited factors have been implicated in the etiology of OA. In addition to physical damage to the joint, a role for inflammatory processes has been identified as well. Small heterodimer partner-interacting leucine zipper protein (SMILE) regulates transcription and many cellular functions. Among the proteins activated by SMILE is the peroxisome proliferator-activated receptor (PPAR) γ, which mediates the activities of CD4 + T helper cells, including Th1, Th2, and Th17, as well as Treg cells. PPAR-γ binds to STAT3 to inhibit its transcription, thereby suppressing the expression of the NF-κB pathway, and in turn, the expression of the inflammatory cytokines interferon (IFN), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, which are sub-signals of STAT3 and NF-κB. Methods OA was induced in control C57BL/6 mice and in C57BL/6-derived SMILE-overexpressing transgenic (SMILE Tg) mice. The protein expression levels in the joint and spleen tissues were analyzed by immunohistochemistry and immunofluorescence images. In addition, flow cytometry was performed for detecting changes of the changes of immune cells. Results Less cartilage damage and significantly reduced levels of OA biomarkers (MMP13, TIMP3 and MCP-1) were observed in SMILE Tg mice. Immunohistochemistry performed to identify the signaling pathway involved in the link between SMILE expression and OA revealed decreased levels of IL-1β, IL-6, TNF-α, and phosphorylated AMPK in synovial tissues as well as a significant decrease in phosphorylated STAT3 in both cartilage and synovium. Changes in systemic immune cells were investigated via flow cytometry to analyze splenocytes isolated from control and SMILE Tg mice. SMILE Tg mice had elevated proportions of CD4 + IL-4 + cells (Th2) and CD4 + CD25 + Foxp3 + cells (Treg) and a notable decrease in CD4 + IL-17 + cells (Th17). Conclusion Our results show that overexpressed SMILE attenuates the symptoms of OA, by increasing AMPK signaling and decreasing STAT3, thus reducing the levels of inflammatory immune cells.

Nerve decompression is an emerging surgical treatment option for patients with occipital neuralgia. However, limited research is available on the efficacy of this treatment in South Korea. This retrospective study evaluates the efficacy of nerve decompression surgery in patients with chronic migraines, specifically focusing on occipital neuralgia, in South Korea. Between January 2019 and December 2022, six patients diagnosed with occipital neuralgia, who had not responded to conservative treatments, underwent nerve decompression surgery. This procedure, performed under local anesthesia, involved decompression of the greater and/or lesser occipital nerves. Patient data were analyzed for headache frequency and intensity (using the Numeric Rating Scale [NRS]) and the decrease in oral medications needed postsurgery. Results showed significant improvement in headache symptoms postsurgery, with the average preoperative NRS score of 7.9 dropping to 3.7 postoperatively. Additionally, the average number of medications used decreased from 3.2 to 1.3. No significant surgical complications were reported. The study highlights the potential of nerve decompression as an effective treatment for occipital neuralgia, particularly in cases resistant to traditional medical management.

Objectives: The objective is to evaluate the feasibility and safety of ArtiSential for performing minimally invasive surgeries for gynecological cancers. Materials and Methods: We conducted a prospective observational study at 10 Tertiary Institutional Hospitals in Korea between November 2021 and April 2022. Eligible patients were 18 years or older and planned to undergo minimally invasive surgery for gynecologic cancer. We collected baseline characteristics, surgical information, and postoperative outcomes. The primary endpoint was to compare the operation time required for gynecologic cancer surgery using ArtiSential with the reported operation time for surgery using conventional laparoscopic instruments or robots. The secondary endpoints were to evaluate the surgical outcomes of gynecologic cancer surgery using ArtiSential compared to conventional laparoscopic instruments or robots and collect operator feedback on equipment improvements during surgery. Results: Forty patients were enrolled in this study, including 19 with endometrial cancer, 15 with cervical cancer, and 6 with ovarian cancer. The average operation time was 187.0 ± 49.2 min, with no complications encountered during surgery. Pelvic lymph nodes were assessed in 34 patients, with the ArtiSential device utilized in 22 (64.7%) of these patients, at an average assessment time of 40.3 ± 19.4 min. Most surgeons using the ArtiSential device reported that it performed slightly better than conventional laparoscopic instruments. Conclusion: The use of the ArtiSential device in minimally invasive surgery has been demonstrated to be both feasible and safe for the treatment of early-stage gynecologic cancer.

Taste buds, the neuroepithelial organs responsible for the detection of gustatory stimuli in the oral cavity, arise from stem/progenitor cells among nearby basal keratinocytes. Using genetic lineage tracing, Lgr5 and Lgr6 were suggested as the specific markers for the stem/progenitor cells of taste buds, but recent evidence implied that taste buds may arise even in the absence of these markers. Thus, we wanted to verify the genetic lineage tracing of lingual Lgr5- and Lgr6-expressing cells. Unexpectedly, we found that antibody staining revealed more diverse Lgr5-expressing cells inside and outside the taste buds of circumvallate papillae than was previously suggested. We also found that, while tamoxifen-induced genetic recombination occurred only in cells expressing the Lgr5 reporter GFP, we did not see any increase in the number of recombined daughter cells induced by consecutive injections of tamoxifen. Similarly, we found that cells expressing Lgr6, another stem/progenitor cell marker candidate and an analog of Lgr5, also do not generate recombined clones. In contrast, Lgr5-expressing cells in fungiform papillae can transform into Lgr5-negative progeny. Together, our data indicate that lingual Lgr5- and Lgr6-expressing cells exhibit diversity in their capacity to transform into Lgr5- and Lgr6-negative cells, depending on their location. Our results complement previous findings that did not distinguish this diversity.