• 제목/요약/키워드: Respiratory protection

검색결과 137건 처리시간 0.022초

An analysis of the potential impact of various ozone regulatory standards on mortality

  • Kim, Yong-Ku
    • Journal of the Korean Data and Information Science Society
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    • 제22권1호
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    • pp.125-136
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    • 2011
  • Ground-level ozone, an air pollutant that is monitored by the Environmental Protection Agency (EPA), damages human health by irritating the respiratory system, reducing lung function, damaging lung cells, and aggravating asthma and other chronic conditions. In March 2008, the EPA strengthened ozone standards by lowering acceptable limits from 84 parts per billion to 75 parts per billion. Here epidemiologic data is used to study the effects of ozone regulation on human health and assessed how various regulatory standards for ozone may affect nonaccidental mortality, including respiratory-related deaths during ozone season. The assessment uses statistical methods based on hierarchical Bayesian models to predict the potential effects of the different regulatory standards. It also analyzes the variability of the results and ho they are impacted by different modeling assumptions. We focused on the technical an statistical approach to assessing relationship between new ozone regulations and mortality while other researches have detailed the relationship between ozone and human mortality. We shows a statistical correlation between ozone regulations and mortality, with lower limits of acceptable ozone linked to a decrease in deaths, and projects that mortality is expected to decrease by reducing ozone regulatory standards.

Extra-phase Image Generation for Its Potential Use in Dose Evaluation for a Broad Range of Respiratory Motion

  • Lee, Hyun Su;Choi, Chansoo;Kim, Chan Hyeong;Han, Min Cheol;Yeom, Yeon Soo;Nguyen, Thang Tat;Kim, Seonghoon;Choi, Sang Hyoun;Lee, Soon Sung;Kim, Jina;Hwang, JinHo;Kang, Youngnam
    • Journal of Radiation Protection and Research
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    • 제44권3호
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    • pp.103-109
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    • 2019
  • Background: Four-dimensional computed tomographic (4DCT) images are increasingly used in clinic with the growing need to account for the respiratory motion of the patient during radiation treatment. One of the reason s that makes the dose evaluation using 4DCT inaccurate is a change of the patient respiration during the treatment session, i.e., intrafractional uncertainty. Especially, when the amplitude of the patient respiration is greater than the respiration range during the 4DCT acquisition, such an organ motion from the larger respiration is difficult to be represented with the 4DCT. In this paper, the method to generate images expecting the organ motion from a respiration with extended amplitude was proposed and examined. Materials and Methods: We propose a method to generate extra-phase images from a given set of the 4DCT images using deformable image registration (DIR) and linear extrapolation. Deformation vector fields (DVF) are calculated from the given set of images, then extrapolated according to respiratory surrogate. The extra-phase images are generated by applying the extrapolated DVFs to the existing 4DCT images. The proposed method was tested with the 4DCT of a physical 4D phantom. Results and Discussion: The tumor position in the generated extra-phase image was in a good agreement with that in the gold-standard image which is separately acquired, using the same 4DCT machine, with a larger range of respiration. It was also found that we can generate the best quality extra-phase image by using the maximum inhalation phase (T0) and maximum exhalation phase (T50) images for extrapolation. Conclusion: In the present study, a method to construct extra-phase images that represent expanded respiratory motion of the patient has been proposed and tested. The movement of organs from a larger respiration amplitude can be predicted by the proposed method. We believe the method may be utilized for realistic simulation of radiation therapy.

Outer Membrane Protein H for Protective Immunity Against Pasteurella multocida

  • Lee, Jeong-Min;Kim, Young-Bong;Kwon, Moo-Sik
    • Journal of Microbiology
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    • 제45권2호
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    • pp.179-184
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    • 2007
  • Pasteurella multocida, a Gram-negative facultative anaerobic bacterium, is a causative animal pathogen in porcine atrophic rhinitis and avian fowl cholera. For the development of recombinant subunit vaccine against P. multocida, we cloned and analyzed the gene for outer membrane protein H (ompH) from a native strain of Pasteurella multocida in Korea. The OmpH had significant similarity in both primary and secondary structure with those of other serotypes. The full-length, and three short fragments of ompH were expressed in E. coli and the recombinant OmpH proteins were purified, respectively. The recombinant OmpH proteins were antigenic and detectable with antisera produced by either immunization of commercial vaccine for respiratory disease or formalin-killed cell. Antibodies raised against the full-length OmpH provided strong protection against P. multocida, however, three short fragments of recombinant OmpHs, respectively, showed slightly lower protection in mice challenge. The recombinant OmpH might be a useful vaccine candidate antigen for P. multocida.

Vaccine Strategy That Enhances the Protective Efficacy of Systemic Immunization by Establishing Lung-Resident Memory CD8 T Cells Against Influenza Infection

  • Hyun-Jung Kong;Youngwon Choi;Eun-Ah Kim;Jun Chang
    • IMMUNE NETWORK
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    • 제23권4호
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    • pp.32.1-32.15
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    • 2023
  • Most influenza vaccines currently in use target the highly variable hemagglutinin protein to induce neutralizing antibodies and therefore require yearly reformulation. T cell-based universal influenza vaccines focus on eliciting broadly cross-reactive T-cell responses, especially the tissue-resident memory T cell (TRM) population in the respiratory tract, providing superior protection to circulating memory T cells. This study demonstrated that intramuscular (i.m.) administration of the adenovirus-based vaccine expressing influenza virus nucleoprotein (rAd/NP) elicited weak CD8 TRM responses in the lungs and airways, and yielded poor protection against lethal influenza virus challenge. However, a novel "prime-and-deploy" strategy that combines i.m. vaccination of rAd/NP with subsequent intranasal administration of an empty adenovector induced strong NP-specific CD8+ TRM cells and provided complete protection against influenza virus challenge. Overall, our results demonstrate that this "prime-and-deploy" vaccination strategy is potentially applicable to the development of universal influenza vaccines.

공기중 I-131 농도 감시에 의한 갑상선 피폭 평가법의 적용성 (Assessment of Thyroid Dose Evaluation Method by Monitoring of I-131 Concentration in Air)

  • 이종일;서경원
    • Journal of Radiation Protection and Research
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    • 제19권1호
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    • pp.69-80
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    • 1994
  • 공기중방사성요드 농도로부터 체내피폭선량을 간편하게 평가할 수 있는 전산프로그램 TCMI(Three-Compartment Model for iodine)를 개발하였다. 이 프로그램은 국제방사선방어위원회 권고 54(ICRP Publ. 54)의 3격실모델 및 호흡기모델에 따라 작업시간과 작업장의 공기중 방사성요드 농도로부터 갑상선부하량, 선량당량, 예탁선량당량 및 뇨를 통한 배출율을 시간의 함수로 평가한다. TCMI 코드를 이용함으로써 급성, 만성 및 급만성 등 구체적 피폭형태에 따른 갑상선부 하량과 선량당량 그리고 뇨를 통한 배출율을 평가하여 체내피폭평가의 적용성을 검토하였다. 또한 공기중 I-131 농도와 작업시간에 따른 갑상선부하량과 피폭선량을 간편하게 평가할 수 있는 식과 표를 제시하였다.

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ICRP 호흡기 및 생체역동학적 모델을 이용한 우라늄 생물분석 결과의 해석 (Interpretation of Uranium Bioassay Results with the ICRP Respiratory Track and Biokinetic Model)

  • 김현기;이재기
    • Journal of Radiation Protection and Research
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    • 제28권1호
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    • pp.43-50
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    • 2003
  • 본 연구는 호흡을 통해 우라늄을 만성 또는 급성섭취한 경우 생물분석 결과의 해석을 통해 예탁유효선량을 평가하는 실질적인 방법을 기술하고 있다. 인체에서의 우라늄 거동의 해석을 위해 인체의 장기를 ICRP에서 권고하는 소화기 모델, 호흡기 모델 그리고 생체역동학적 모델에 따라 일련의 수학적 격실로 구성하였다. Birchall의 알고리듬을 이용하여 각 격실에서의 균형방정식의 해석적인 해를 얻었으며 우라늄의 소변 배설함수와 폐 잔류함수를 획득하였다. 소변 중 우라늄 농도와 폐 계수기로 측정된 폐 부하량에 각각 배설 및 잔류함수를 적용하여 섭취모드에 따른 초기 섭취량 또는 총 섭취량을 계산하였다. 예탁유효선량은 ICRP 78에서 제공하는 선량 환산계수를 계산된 섭취량에 적용함으로써 평가된다.

Impact of the COVID-19 vaccine booster strategy on vaccine protection: a pilot study of a military hospital in Taiwan

  • Yu-Li Wang;Shu-Tsai Cheng;Ching-Fen Shen;Shu-Wei Huang;Chao-Min Cheng
    • Clinical and Experimental Vaccine Research
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    • 제12권4호
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    • pp.337-345
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    • 2023
  • Purpose: The global fight against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has led to widespread vaccination efforts, yet the optimal dosing schedule for SARS-CoV-2 vaccines remains a subject of ongoing research. This study aims to investigate the effectiveness of administering two booster doses as the third and fourth doses at different intervals to enhance vaccine protection. Materials and Methods: This study was conducted at a military regional hospital operated by the Ministry of National Defense in Taiwan. A cohort of vaccinated individuals was selected, and their vaccine potency was assessed at various time intervals following their initial vaccine administration. The study participants received booster doses as the third and fourth doses, with differing time intervals between them. The study monitored neutralizing antibody titers and other relevant parameters to assess vaccine efficacy. Results: Our findings revealed that the potency of the SARS-CoV-2 vaccine exhibited a significant decline 80 days after the initial vaccine administration. However, a longer interval of 175 days between booster injections resulted in significantly higher neutralizing antibody titers. The individuals who received the extended interval boosters exhibited a more robust immune response, suggesting that a vaccine schedule with a 175-day interval between injections may provide superior protection against SARS-CoV-2. Conclusion: This study underscores the importance of optimizing vaccine booster dosing schedules to maximize protection against SARS-CoV-2. The results indicate that a longer interval of 175 days between the third and fourth doses of the vaccine can significantly enhance the neutralizing antibody response, potentially offering improved protection against the virus. These findings have important implications for vaccine distribution and administration strategies in the ongoing battle against the SARS-CoV-2 pandemic. Further research and largescale trials are needed to confirm and extend these findings for broader public health implications.

Preventing the Transmission of Tuberculosis in Health Care Settings: Administrative Control

  • Jo, Kyung-Wook
    • Tuberculosis and Respiratory Diseases
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    • 제80권1호
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    • pp.21-26
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    • 2017
  • It is well established that health care workers (HCWs) have a considerably higher risk of occupationally acquired tuberculosis (TB). To reduce the transmission of TB to HCWs and patients, TB infection control programs should be implemented in health care settings. The first and most important level of all protection and control programs is administrative control. Its goals are to prevent HCWs, other staff, and patients from being exposed to TB, and to reduce the transmission of infection by ensuring rapid diagnosis and treatment of affected individuals. Administrative control measures recommended by the United States Centers for Disease Control and Prevention and the World Health Organization include prompt identification of people with TB symptoms, isolation of infectious patients, control of the spread of the pathogen, and minimization of time spent in health care facilities. Another key component of measures undertaken is the baseline and serial screening for latent TB infection in HCWs who are at risk of exposure to TB. Although the interferon-gamma release assay has some advantages over the tuberculin skin test, the former has serious limitations, mostly due to its high conversion rate.

Implementation of Cough Detection System Using IoT Sensor in Respirator

  • Shin, Woochang
    • International journal of advanced smart convergence
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    • 제9권4호
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    • pp.132-138
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    • 2020
  • Worldwide, the number of corona virus disease 2019 (COVID-19) confirmed cases is rapidly increasing. Although vaccines and treatments for COVID-19 are being developed, the disease is unlikely to disappear completely. By attaching a smart sensor to the respirator worn by medical staff, Internet of Things (IoT) technology and artificial intelligence (AI) technology can be used to automatically detect the medical staff's infection symptoms. In the case of medical staff showing symptoms of the disease, appropriate medical treatment can be provided to protect the staff from the greater risk. In this study, we design and develop a system that detects cough, a typical symptom of respiratory infectious diseases, by applying IoT technology and artificial technology to respiratory protection. Because the cough sound is distorted within the respirator, it is difficult to guarantee accuracy in the AI model learned from the general cough sound. Therefore, coughing and non-coughing sounds were recorded using a sensor attached to a respirator, and AI models were trained and performance evaluated with this data. Mel-spectrogram conversion method was used to efficiently classify sound data, and the developed cough recognition system had a sensitivity of 95.12% and a specificity of 100%, and an overall accuracy of 97.94%.

Reopening of dental clinics during SARS-CoV-2 pandemic: an evidence-based review of literature for clinical interventions

  • Keyhan, Seied Omid;Fallahi, Hamid Reza;Motamedi, Amin;Khoshkam, Vahid;Mehryar, Paymon;Moghaddas, Omid;Cheshmi, Behzad;Firoozi, Parsa;Yousefi, Parisa;Houshmand, Behzad
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제42권
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    • pp.25.1-25.13
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    • 2020
  • Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes serious acute respiratory diseases including pneumonia and bronchitis with approximately 2.3% fatality occurrence. Main body: This study argues the main concepts that need to be considered for the gradual reopening of dental offices include treatment planning approaches, fundamental elements needed to prevent transmission of SARS-CoV-2 virus in dental healthcare settings, personal protection equipment (PPE) for dental health care providers, environmental measures, adjunctive measures, and rapid point of care tests in dental offices. Conclusion: This article seeks to provide an overview of existing scientific evidence to suggest a guideline for reopening dental offices.