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1.
J Mol Cell Cardiol ; 187: 101-117, 2024 02.
Article in English | MEDLINE | ID: mdl-38331556

ABSTRACT

AIMS: The sympathetic nervous system regulates numerous critical aspects of mitochondrial function in the heart through activation of adrenergic receptors (ARs) on cardiomyocytes. Mounting evidence suggests that α1-ARs, particularly the α1A subtype, are cardioprotective and may mitigate the deleterious effects of chronic ß-AR activation by shared ligands. The mechanisms underlying these adaptive effects remain unclear. Here, we tested the hypothesis that α1A-ARs adaptively regulate cardiomyocyte oxidative metabolism in both the uninjured and infarcted heart. METHODS: We used high resolution respirometry, fatty acid oxidation (FAO) enzyme assays, substrate-specific electron transport chain (ETC) enzyme assays, transmission electron microscopy (TEM) and proteomics to characterize mitochondrial function comprehensively in the uninjured hearts of wild type and α1A-AR knockout mice and defined the effects of chronic ß-AR activation and myocardial infarction on selected mitochondrial functions. RESULTS: We found that isolated cardiac mitochondria from α1A-KO mice had deficits in fatty acid-dependent respiration, FAO, and ETC enzyme activity. TEM revealed abnormalities of mitochondrial morphology characteristic of these functional deficits. The selective α1A-AR agonist A61603 enhanced fatty-acid dependent respiration, fatty acid oxidation, and ETC enzyme activity in isolated cardiac mitochondria. The ß-AR agonist isoproterenol enhanced oxidative stress in vitro and this adverse effect was mitigated by A61603. A61603 enhanced ETC Complex I activity and protected contractile function following myocardial infarction. CONCLUSIONS: Collectively, these novel findings position α1A-ARs as critical regulators of cardiomyocyte metabolism in the basal state and suggest that metabolic mechanisms may underlie the protective effects of α1A-AR activation in the failing heart.


Subject(s)
Myocardial Contraction , Myocardial Infarction , Animals , Mice , Fatty Acids/metabolism , Mice, Knockout , Mitochondria/metabolism , Myocardial Infarction/metabolism , Oxidative Stress , Receptors, Adrenergic, alpha-1/metabolism
2.
Nat Chem ; 15(10): 1358-1364, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37537296

ABSTRACT

Interpenetrated metal-organic frameworks (MOFs) comprise two or more lattices that are mutually entangled. Interpenetration can be used to tune the structures and pore architectures of MOFs to influence, for example, their stability or interactions with guest molecules. The interpenetrating sublattices are typically identical, but hetero-interpenetrated MOFs, which consist of sublattices that are different from one another, have also been serendipitously produced. Here we describe a strategy for the deliberate synthesis of hetero-interpenetrated MOFs. We use the cubic α-MUF-9 framework as a host sublattice to template the growth of a second sublattice within its pores. Three different secondary sublattices are grown-two of which are not known as standalone MOFs-leading to three different hetero-interpenetrated MOFs. This strategy may serve to combine different properties into one material. We produce an asymmetric catalysis by allocating separate roles to the interpenetrating sublattices in a hetero-interpenetrated MOF: an achiral secondary amine on one sublattice provides the catalytic activity, while the chiral α-MUF-10 host imparts asymmetry to aldol and Henry reactions.

3.
Angew Chem Int Ed Engl ; 62(44): e202306341, 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37344359

ABSTRACT

Metal-organic frameworks (MOFs) are constructed from metal ions or clusters and organic linkers. Typical MOFs are rather simple, comprising just one type of joint and linker. An additional degree of structural complexity can be introduced by using multiple different components that are assembled into the same framework In the early days of MOF chemistry, conventional wisdom held that attempting to prepare frameworks starting from such a broad set of components would lead to multiple different phases. However, this review highlights how this view was mistaken and frameworks comprising multiple different components can be deliberately designed and synthesized. When coupled to structural order and periodicity, the presence of multiple components leads to exceptional functional properties that can be understood at the atomic level.

5.
Sci Rep ; 13(1): 3207, 2023 Feb 24.
Article in English | MEDLINE | ID: mdl-36828881

ABSTRACT

We present overall process for developing terahertz (THz) corrugated structure and its beam-based measurement results. 0.2-THz corrugated structures were fabricated by die stamping method as the first step demonstration towards GW THz radiation source and GV/m THz wakefield accelerator. 150-[Formula: see text]m thick disks were produced from an OFHC (C10100) foil by stamping. Two types of disks were stacked alternately to form 46 mm structure with [Formula: see text] 170 corrugations. Custom assembly was designed to provide diffusion bonding with a high precision alignment of disks. The compliance of the fabricated structure have been verified through beam-based wakefield measurement at Argonne Wakefield Accelerator Facility. Both measured longitudinal and transverse wakefield showed good agreement with simulated wakefields. Measured peak gradients, 9.4 MV/m/nC for a long single bunch and 35.4 MV/m/nC for a four bunch trains, showed good agreement with the simulation.

6.
J Air Waste Manag Assoc ; 73(5): 362-373, 2023 05.
Article in English | MEDLINE | ID: mdl-36809316

ABSTRACT

The chemical industry releases various types of volatile organic compounds (VOCs) into the atmosphere, and the concentration of VOCs emitted from chimneys is regulated worldwide. However, some VOCs such as benzene are highly carcinogenic, while others such as ethylene and propylene may cause secondary air pollution, owing to their high ozone-generating ability. Accordingly, the US EPA(United State, Environment Protect Agency) introduced a fenceline monitoring system that regulates the concentration of VOCs at the boundary of a facility, away from the chimney source. This system was first introduced in the petroleum refining industry, which simultaneously emits benzene, affecting the local community because of its high carcinogenicity, and ethylene, propylene, xylene, and toluene, which have a high photochemical ozone creation potential (POCP). These emissions contribute to air pollution. In Korea, the concentration at the chimney is regulated; however, the concentration at the plant boundary is not considered. In accordance with the EPA regulations, Korea's petroleum refining industries were identified and the limitations of the Clean Air Conservation Act were studied. The average concentration of benzene at the research facility examined in this study was 8.53 µg/m3, which complied with the benzene action level of 9 µg/m3. However, this value was exceeded at some points along the fenceline, in proximity to the benzene-toluene-xylene (BTX) manufacturing process. The composition ratios of toluene and xylene were 27% and 16%, respectively, which were higher than those of ethylene or propylene. These results suggest that reduction measures in the BTX manufacturing process are necessary. This study shows that legal regulations should enforce reduction measures through continuous monitoring at the fenceline of petroleum refineries in Korea.Implications: Although volatile organic compounds(VOCs) are essential in various industrial sites, they adversely affect the health of people in the near community. Benzene is highly carcinogenic, so it is dangerous if exposed continuously. In addition, there are various types of VOCs, which combine with atmospheric ozone to generate smog. Globally, VOCs are managed as Total VOCs. However, through this study, VOCs have priority, and in the case of the petroleum refining industry, it is suggested that VOCs should be preemptively measured and analyzed to be regulated. In addition, it is necessary to minimize the impact on the local community by regulating the concentration at the fenceline beyond the chimney measurement.


Subject(s)
Air Pollutants , Ozone , Petroleum , Volatile Organic Compounds , Humans , Air Pollutants/analysis , Volatile Organic Compounds/analysis , Benzene , Xylenes/analysis , Conservation of Natural Resources , Feasibility Studies , Environmental Monitoring/methods , Toluene/analysis , Ethylenes , China
7.
Article in English | MEDLINE | ID: mdl-34831738

ABSTRACT

Chemical accidents can occur anywhere. The need for chemical management in Korea was realized following the 2012 Gumi hydrofluoric acid accident in 2012. The Chemicals Control Act was enacted in 2015. This system evaluates the risks (high, medium, low) and consequent safety management at all plants that handle hazardous chemical substances. However, the system was criticized as excessive when most plants were designated high-risk without considering their size. Thus, laboratories and hospitals handling very small quantities were subject to regulation. Accordingly, in 2021 Korea revised the system to include off-site consequence analyses and a Korean-style risk analysis. Plants handling very small quantities, such as laboratories and hospitals, were exempt from regulation. In this study, changes in risk were examined for four medium-sized plating and paint manufacturing plants. Under the previous system, all four factories were judged as high-risk groups. In particular, the paint manufacturing plant A, which has an underground storage tank, received a medium risk like the plating plant C, although the possibility of a chemical accident was lower than that of other plants. However, in the changed system, all plants were changed to the low-risk group. In the Korean-style risk analysis, it is possible to see at a glance what is lacking in the plants, such as cooperation between local residents and local governments and the construction of safety facilities according to the type of accident scenario. The revised system is a reasonable regulation for medium business plants.


Subject(s)
Chemical Hazard Release , Accident Prevention , Hazardous Substances , Manufacturing and Industrial Facilities , Paint , Republic of Korea , Risk Assessment
8.
Eur J Cancer ; 151: 190-200, 2021 07.
Article in English | MEDLINE | ID: mdl-34010788

ABSTRACT

BACKGROUND: Adding ovarian function suppression (OFS) after chemotherapy improves survival in young women with moderate- and high-risk breast cancer. Assessment of ovarian function restoration after chemotherapy becomes critical for subsequent endocrine treatment and addressing fertility issues. PATIENTS AND METHODS: In the adding OFS after chemotherapy trial, patients who resumed ovarian function up to 2 years after chemotherapy were randomised to receive either 5 years of tamoxifen or adding 2 years of OFS with tamoxifen. Ovarian function was evaluated from enrolment to randomisation, and patients who did not randomise because of amenorrhoea for 2 years received tamoxifen and were followed up for 5 years. Prospectively collected consecutive hormone levels (proportion of patients with premenopausal follicle-stimulating hormone [FSH] levels <30 mIU/mL and oestradiol [E2] levels ≥40 pg/mL) and history of menstruation were available for 1067 patients with breast cancer. RESULTS: Over 5 years of tamoxifen treatment, 69% of patients resumed menstruation and 98% and 74% of patients satisfied predefined ovarian function restoration as per serum FSH and E2 levels, respectively. Menstruation was restored in 91% of patients younger than 35 years at baseline, but in only 33% of 45-year-old patients over 5 years. Among these patients, 41% experienced menstruation restoration within 2 years after chemotherapy and 28% slowly restored menstruation after 2-5 years. Younger age (<35 years) at baseline, anthracycline without taxanes and ≤90 days of chemotherapy were predictors of menstruation restoration. CONCLUSIONS: During 5 years of tamoxifen treatment after chemotherapy, two-thirds of the patients experienced menstruation restoration, especially patients younger than 35 years. Young age, Adriamycin without taxanes and short duration of chemotherapy appeared to have a positive effect on ovarian reserves in the long term. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00912548.


Subject(s)
Antineoplastic Agents, Hormonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Menstruation/drug effects , Ovary/drug effects , Premenopause , Tamoxifen/therapeutic use , Adult , Age Factors , Antineoplastic Agents, Hormonal/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biomarkers/blood , Estradiol/blood , Female , Follicle Stimulating Hormone, Human/blood , Humans , Menstruation/blood , Middle Aged , Ovary/metabolism , Ovary/physiopathology , Recovery of Function , Republic of Korea , Risk Assessment , Risk Factors , Tamoxifen/adverse effects , Time Factors , Treatment Outcome , Young Adult
9.
Saf Health Work ; 11(4): 418-424, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33329907

ABSTRACT

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.

10.
Eur J Neurol ; 27(10): 2079-2088, 2020 10.
Article in English | MEDLINE | ID: mdl-32478888

ABSTRACT

BACKGROUND AND PURPOSE: Hidden hearing loss has been reported in patients with Charcot-Marie-Tooth (CMT) disease; however, the auditory-processing deficits have not been widely explored. We investigated the psychoacoustic and neurophysiological aspects of auditory processing in patients with CMT disease type 1A (CMT1A) and type 2A (CMT2A). METHODS: A total of 43 patients with CMT1A and 15 patients with CMT2A were prospectively enrolled. All patients with CMT disease had normal sound-detection ability by using pure-tone audiometry. Spectral-ripple discrimination, temporal modulation detection and auditory frequency-following response were compared between CMT1A, CMT2A and control groups. RESULTS: Although all participants had normal audiograms, patients with CMT disease had difficulty understanding speech in noise. The psychoacoustic auditory processing was somewhat different depending on the underlying pathophysiology of CMT disease. Patients with CMT1A had degraded auditory temporal and spectral processing. Patients with CMT2A had no reduced spectral resolution, but they showed further reduced temporal resolution than the patients with CMT1A. The amplitudes of the frequency-following response were reduced in patients with CMT1A and CMT2A, but the neural timing remained relatively intact. CONCLUSIONS: When we first assessed the neural representation to speech at the brainstem level, the grand average brainstem responses were reduced in both patients with CMT1A and CMT2A compared with healthy controls. As the psychoacoustic aspects of auditory dysfunctions in CMT1A and CMT2A were somewhat different, it is necessary to consider future auditory rehabilitation methods based on their pathophysiology.


Subject(s)
Charcot-Marie-Tooth Disease , Auditory Perception , Charcot-Marie-Tooth Disease/complications , Humans , Neurophysiology , Psychoacoustics
11.
Plast Reconstr Surg ; 146(3): 552-562, 2020 09.
Article in English | MEDLINE | ID: mdl-32459729

ABSTRACT

BACKGROUND: Traumatic muscle loss often results in poor functional restoration. Skeletal muscle injuries cannot be repaired without substantial fibrosis and loss of muscle function. Given its regenerative properties, the authors evaluated outcomes of fetal tissue-derived decellularized matrix for skeletal muscle regeneration. The authors hypothesized that fetal matrix would lead to enhanced myogenesis and suppress inflammation and fibrosis. METHODS: Composite tissue composed of dermis, subcutaneous tissue, and panniculus carnosus was harvested from the trunk of New Zealand White rabbit fetuses on gestational day 24 and from Sprague-Dawley rats on gestational day 18 and neonatal day 3, and decellularized using a sodium dodecyl sulfate-based negative-pressure protocol. Six, 10-mm-diameter, full-thickness rat latissimus dorsi wounds were created for each treatment, matrix was implanted (excluding the defect groups), and the wounds were allowed to heal for 60 days. Analyses were performed to characterize myogenesis, neovascularization, inflammation, and fibrosis at harvest. RESULTS: Significant myocyte ingrowth was visualized in both allogeneic and xenogeneic fetal matrix groups compared to neonatal and defect groups based on myosin heavy chain immunofluorescence staining. Microvascular networks were appreciated within all implanted matrices. At day 60, expression of Ccn2, Col1a1, and Ptgs2 were decreased in fetal matrix groups compared to defect. Neonatal matrix-implanted wounds failed to show decreased expression of Col1a1 or Ptgs2, and demonstrated increased expression of Tnf, but also demonstrated a significant reduction in Ccn2 expression. CONCLUSIONS: Initial studies of fetal matrices demonstrate promise for muscle regeneration in a rat latissimus dorsi model. Further research is necessary to evaluate fetal matrix for future translational use and better understand its effects.


Subject(s)
Extracellular Matrix/genetics , Gene Expression Regulation , Muscle Development/genetics , Muscle, Skeletal/injuries , Pregnancy, Animal , Tissue Engineering/methods , Tissue Scaffolds , Animals , Animals, Newborn , Blotting, Western , Extracellular Matrix/metabolism , Female , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Pregnancy , RNA/genetics , Rabbits , Rats , Rats, Sprague-Dawley
12.
Eur J Cancer ; 133: 56-65, 2020 07.
Article in English | MEDLINE | ID: mdl-32442924

ABSTRACT

BACKGROUND: This study assessed the effects of gonadotropin-releasing hormone agonists (GnRHa) on the prevention of chemotherapy-induced ovarian insufficiency among young patients with malignant ovarian germ cell tumour (MOGCT) receiving chemotherapy. METHODS: This multicentre, retrospective study was conducted at 15 sites affiliated with the Korean Gynecologic Oncology Group and enrolled 354 patients between January 1995 and September 2018. Among them, 227 patients were included in this study and divided into two groups according to the use of GnRHa during chemotherapy (GnRHa versus no GnRHa groups). The primary objective was to compare the rates of menstrual resumption between the two groups. We also assessed the clinical determinants affecting menstrual resumption among the study groups. RESULTS: There were no significant differences between the GnRHa (n = 63) and no GnRHa (n = 164) groups regarding age at diagnosis, parity, ethnicity, age at menarche, body mass index, International Federation of Gynecology and Obstetrics stage, mode of surgery and surgery type. The rate of menstrual resumption after chemotherapy was 100% (63 of 63) in the GnRHa group and 90.9% (149 of 164) in the no GnRHa group (p = 0.013). The mean periods from last chemotherapy to menstrual resumption were 7.4 and 7.3 months in the GnRHa and no GnRHa groups, respectively. GnRHa co-administration during chemotherapy reduced the likelihood of amenorrhoea after chemotherapy, although statistical significance was not confirmed in the univariate analysis (odds ratio: 0.276; 95% confidence interval, 0.004-1.317; p = 0.077). CONCLUSION: Temporary ovarian suppression with GnRHa during chemotherapy does not significantly increase the chances of menstrual resumption in young patients with MOGCT.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Fertility Agents, Female/therapeutic use , Gonadotropin-Releasing Hormone/agonists , Neoplasms, Germ Cell and Embryonal/drug therapy , Ovarian Neoplasms/drug therapy , Primary Ovarian Insufficiency/chemically induced , Primary Ovarian Insufficiency/prevention & control , Adolescent , Adult , Amenorrhea/chemically induced , Amenorrhea/epidemiology , Amenorrhea/prevention & control , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Bleomycin/administration & dosage , Bleomycin/adverse effects , Cisplatin/administration & dosage , Cisplatin/adverse effects , Etoposide/administration & dosage , Etoposide/adverse effects , Feasibility Studies , Female , Fertility Preservation/methods , Humans , Infertility, Female/chemically induced , Infertility, Female/epidemiology , Infertility, Female/prevention & control , Menopause, Premature/drug effects , Menstruation/drug effects , Neoplasms, Germ Cell and Embryonal/epidemiology , Ovarian Neoplasms/epidemiology , Ovary/drug effects , Pregnancy , Primary Ovarian Insufficiency/epidemiology , Republic of Korea/epidemiology , Retrospective Studies , Treatment Outcome , Young Adult
13.
Phys Rev Lett ; 124(4): 044802, 2020 Jan 31.
Article in English | MEDLINE | ID: mdl-32058730

ABSTRACT

Plasma wakefields can enable very high accelerating gradients for frontier high energy particle accelerators, in excess of 10 GeV/m. To overcome limits on single stage acceleration, specially shaped drive beams can be used in both linear and nonlinear plasma wakefield accelerators (PWFA), to increase the transformer ratio, implying that the drive beam deceleration is minimized relative to acceleration obtained in the wake. In this Letter, we report the results of a nonlinear PWFA, high transformer ratio experiment using high-charge, longitudinally asymmetric drive beams in a plasma cell. An emittance exchange process is used to generate variable drive current profiles, in conjunction with a long (multiple plasma wavelength) witness beam. The witness beam is energy modulated by the wakefield, yielding a response that contains detailed spectral information in a single-shot measurement. Using these methods, we generate a variety of beam profiles and characterize the wakefields, directly observing transformer ratios up to R=7.8. Furthermore, a spectrally based reconstruction technique, validated by 3D particle-in-cell simulations, is introduced to obtain the drive beam current profile from the decelerating wake data.

14.
IUBMB Life ; 72(4): 601-606, 2020 04.
Article in English | MEDLINE | ID: mdl-32027092

ABSTRACT

The sodium channel NaX (encoded by the SCN7A gene) was originally identified in the heart and skeletal muscle and is structurally similar to the other voltage-gated sodium channels but does not appear to be voltage gated. Although NaX is expressed at high levels in cardiac and skeletal muscle, little information exists on the function of NaX in these tissues. Transcriptional profiling of ion channels in the heart in a subset of patients with Brugada syndrome revealed an inverse relationship between the expression of NaX and NaV 1.5 suggesting that, in cardiac myocytes, the expression of these channels may be linked. We propose that NaX plays a role in excitation-contraction coupling based on our experimental observations. Here we show that in cardiac myocytes, NaX is expressed in a striated pattern on the sarcolemma in regions corresponding to the sarcomeric M-line. Knocking down NaX expression decreased NaV 1.5 mRNA and protein and reduced the inward sodium current (INa+ ) following cell depolarization. When the expression of NaV 1.5 was knocked down, ~85% of the INa+ was reduced consistent with the observations that NaV 1.5 is the main voltage-gated sodium channel in cardiac muscle and that NaX likely does not directly participate in mediating the INa+ following depolarization. Silencing NaV 1.5 expression led to significant upregulation of NaX mRNA. Similar to NaV 1.5, NaX protein levels were rapidly downregulated when the intracellular [Ca2+ ] was increased either by CaCl2 or caffeine. These data suggest that a relationship exists between NaX and NaV 1.5 and that NaX may play a role in excitation-contraction coupling.


Subject(s)
Myocytes, Cardiac/metabolism , Voltage-Gated Sodium Channels/metabolism , Animals , Brugada Syndrome/genetics , Calcium/metabolism , Cells, Cultured , Dogs , Gene Knockdown Techniques , Humans , Myocardial Contraction/physiology , NAV1.5 Voltage-Gated Sodium Channel/genetics , NAV1.5 Voltage-Gated Sodium Channel/metabolism , Rats , Sarcomeres/metabolism , Voltage-Gated Sodium Channels/genetics
15.
Angew Chem Int Ed Engl ; 59(15): 6090-6098, 2020 Apr 06.
Article in English | MEDLINE | ID: mdl-31984603

ABSTRACT

The resurgence of interest in the hydrogen economy could hinge on the distribution of hydrogen in a safe and efficient manner. Whilst great progress has been made with cryogenic hydrogen storage or liquefied ammonia, liquid organic hydrogen carriers (LOHCs) remain attractive due to their lack of need for cryogenic temperatures or high pressures, most commonly a cycle between methylcyclohexane and toluene. Oxidation of methylcyclohexane to release hydrogen will be more efficient if the equilibrium limitations can be removed by separating the mixture. This report describes a family of six ternary and quaternary multicomponent metal-organic frameworks (MOFs) that contain the three-dimensional cubane-1,4-dicarboxylate (cdc) ligand. Of these MOFs, the most promising is a quaternary MOF (CUB-30), comprising cdc, 4,4'-biphenyldicarboxylate (bpdc) and tritopic truxene linkers. Contrary to conventional wisdom that adsorptive interactions with larger, hydrocarbon guests are dominated by π-π interactions, here we report that contoured aliphatic pore environments can exhibit high selectivity and capacity for LOHC separations at low pressures. This is the first time, to the best of our knowledge, where selective adsorption for cyclohexane over benzene is witnessed, underlining the unique adsorptive behavior afforded by the unconventional cubane moiety.

16.
Safety and Health at Work ; : 418-424, 2020.
Article in English | WPRIM (Western Pacific) | ID: wpr-903316

ABSTRACT

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.

17.
Safety and Health at Work ; : 418-424, 2020.
Article in English | WPRIM (Western Pacific) | ID: wpr-895612

ABSTRACT

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.

18.
Article in English | MEDLINE | ID: mdl-31491886

ABSTRACT

Industrial chemicals differ in their treatment methods and types, depending on their physicochemical properties. Highly volatile chemicals are emitted despite installation of preventive facilities, such as scrubbers and adsorption towers. Some countries release a Toxic Release Inventory (TRI), which is a mandatory report on the amount of chemicals emitted annually. This report is released to the citizens to ensure their right to knowledge and life. Numerous methods have been devised to investigate the amount of chemical emissions. There are four methods to estimate TRI emissions (Emission Factor Method; Material Balance Method; Source Testing Method; Emission Model Method). Moreover, efforts have been made to increase awareness and formulate plans to reduce chemical emissions. Despite this, the TRI method tends to underestimate and overestimate, especially due to volatile compounds. If the results of the TRI emissions are underestimated, toxic chemicals can have a negative impact on citizens. Volatile compounds are commonly used in chemical manufacturing plants, such as paint plants. In this study, a suitable method for each industrial process was suggested based on conservative estimates of multiple toxic chemical inventory method, focusing on the paint manufacturing process. In the paint manufacturing plant, storage, weighing, and mixing processes should be used emission model method to estimate TRI. In the reaction process, TRI must be estimated by the source test method. In the transfer process, the emission factor method should be used to estimate TRI. In the atmosphere prevention process, the emission factor method or source testing method should be used depending on the physical and chemical properties such as vapor pressure of the chemical.


Subject(s)
Air Pollutants/toxicity , Industry/organization & administration , Manufacturing and Industrial Facilities/organization & administration , Paint , Air Pollutants/analysis
19.
Dalton Trans ; 48(41): 15515-15520, 2019 Nov 07.
Article in English | MEDLINE | ID: mdl-31304498

ABSTRACT

Two iron(iii) spin crossover complexes, [Fe(qsal-X)2]OTs·nH2O, (Br 1·H2O; I, 2·2H2O or non-solvated 1, 2) have been prepared and fully characterized. Structural studies of 1·H2O and 2·2H2O reveal the presence of 1D π-π chains linking the Fe(iii) centres and a strong XO halogen bond. In both complexes the 1D π-π chains are angled relative to each other, enforced by C-HX interactions. Magnetic studies reveal abrupt spin crossover in 1 (T1/2↓ = 258 K and T1/2↑ = 260 K) and 2 (T1/2 = 298 K) with T1/2 increasing on going from Br to I. The presence of abrupt spin crossover in both complexes shows that aromatic anions can be effective in the design of cooperative spin crossover systems.

20.
Angew Chem Int Ed Engl ; 58(34): 11811-11815, 2019 Aug 19.
Article in English | MEDLINE | ID: mdl-31233272

ABSTRACT

Molecular magnetic switches are expected to form the functional components of future nanodevices. Herein we combine detailed (photo-) crystallography and magnetic studies to reveal the unusual switching properties of an iron(III) complex, between low (LS) and high (HS) spin states. On cooling, it exhibits a partial thermal conversion associated with a reconstructive phase transition from a [HS-HS] to a [LS-HS] phase with a hysteresis of 25 K. Photoexcitation at low temperature allows access to a [LS-LS] phase, never observed at thermal equilibrium. As well as reporting the first iron(III) spin crossover complex to exhibit reverse-LIESST (light-induced excited spin state trapping), we also reveal a hidden hysteresis of 30 K between the hidden [LS-LS] and [HS-LS] phases. Moreover, we demonstrate that FeIII spin-crossover (SCO) complexes can be just as effective as FeII systems, and with the advantage of being air-stable, they are ideally suited for use in molecular electronics.

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