Hydrogen peroxide as an auxiliary treatment for COVID-19 in Brazil: a randomized double-blind clinical trial

Marielle Bazzo Di Domê,nico,Kauê, Collares,Renan Brandenburg dos Santos,Ulysses Lenz,Viní,cius Picoli Antunes,Vinicius Webber Godinho,Henrique Cesca,Thales Henrique Jincziwski Ponciano,Pedro Henrique 한국역학회 2021 Epidemiology and Health Vol.43 No.-

OBJECTIVES: This study evaluated the effectiveness of hydrogen peroxide (H2O2) as mouthwash and nasal spray on symptom relief in coronavirus disease 2019 (COVID-19) patients. METHODS: Patients positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), who were treated in a hos-pital or at home, and patients’ family members (not positive for SARS-CoV-2), were randomized into 2 groups: experimental (1% H2O2 for gargling, 0.5% H2O2 for nasal wash), and control. Patients gargled the solution 3 times a day, and applied the nasal spray twice a day, for a 7-day period. Family members received the same treatment as the treated COVID-19 patient. The re-searchers contacted patients every 2 days over an 8-day period. An average post-treatment interval of 8 days passed before test-ing family members. RESULTS: The most frequent symptoms on day 0 were cough, loss of taste, and hyposmia; there were no significant differences between groups, independent of the period. The symptom of dyspnea presented a significant difference between days 2 and 4 (p< 0.05). Among family members, 86.0% had no antibodies, 2.3% had antibodies, and 11.6% had active infections (4 in the ex-perimental group and 6 in the control group). The most frequent adverse effects in the H2O2 group were a burning throat and nose. CONCLUSIONS: H2O2 was not effective for the relief of COVID-19 symptoms and was associated with reports of transient adverse effects.

Effectiveness of hydrogen peroxide as auxiliary treatment for hospitalized COVID-19 patients in Brazil: preliminary results of a randomized double-blind clinical trial

Marielle Bazzo Di Domê,nico,Henrique Cesca,Thales Henrique Jincziwski Ponciano,Renan Brandenburg dos Santos,Ulysses Lenz,Viní,cius Picoli Antunes,Vinicius Webber Godinho,Kauê, Collares,Pedro Henrique 한국역학회 2021 Epidemiology and Health Vol.43 No.-

OBJECTIVES: To evaluate the effectiveness of hydrogen peroxide (H2O2) in the form of mouthwash and nasal spray as an auxiliary treatment for coronavirus disease 2019 (COVID-19). METHODS: Forty hospitalized patients who tested positive for severe acute respiratory syndrome coronavirus 2 using a reverse-transcription polymerase chain reaction test were evaluated. They were randomly divided into an experimental group (n=20; gargling with 1.0% H2O2 and nasal wash with 0.5% H2O2) or a control group (n=20). The solutions were used for 7 days and the patients were monitored every 2 days, for a total of 8 days. At check-ups, patients were asked about their symptoms and possible adverse effects of the solutions. The presence and severity (mild, moderate, or severe) of symptoms were recorded. Data were compared using the Student test and the Fisher exact test (α=0.05). RESULTS: There was no significant difference between the 2 groups in the length of hospital stay (p=0.65). The most frequent symptom on day 0 was coughing (72.0% in the experimental group and 76.5% in the control group), which abated over time. There was no significant difference between the groups in the evaluated symptoms. Most (75.0%) of the patients in the experimental group presented a reduction in dyspnea between days 0 and 2. Few patients reported adverse effects from the use of the solutions. CONCLUSIONS: H2O2 as a mouthwash and nasal spray is safe to use. There is insufficient evidence to demonstrate that H2O2 is effective as an auxiliary treatment for hospitalized COVID-19 patients.

미국의 여론과 대중공정책

마이클 Y. M. 카우(Michael Y. M. Kau),피에르 M. 페롤(Pierre M. Perrolle) 한양대학교 아태지역연구센터 1978 중소연구 Vol.3 No.2

LMI based criterion for reinforced concrete frame structures

Chen, Tim,Kau, Dar,Tai, Y.,Chen, C.Y.J. Techno-Press 2020 Advances in concrete construction Vol.9 No.4

Due to the influence of nonlinearity and time-variation, it is difficult to establish an accurate model of concrete frame structures that adopt active controllers. Fuzzy theory is a relatively appropriate method but susceptible to human subjective experience to decrease the performance. To guarantee the stability of multi-time delays complex system with multi-interconnections, a delay-dependent criterion of evolved design is proposed in this paper. Based on this criterion, the sector nonlinearity which converts the nonlinear model to multiple rule base of the linear model and a new sufficient condition to guarantee the asymptotic stability via Lyapunov function is implemented in terms of linear matrix inequalities (LMI). A numerical simulation for a three-layer reinforced concrete frame structure subjected to earthquakes is demonstrated that the proposed criterion is feasible for practical applications.

Simulation of Impact from Stratospheric Ozone on Global Tropospheric Ozone Distribution with a Chemistry Transport Model: A Case Study during the 1990-1991 Period

Kuo-Ying Wang,Wen-Shung Kau 한국기상학회 2015 Asia-Pacific Journal of Atmospheric Sciences Vol.51 No.2

In this work we examine the effect of ozone (O3) from the stratosphere on the O3 levels in the troposphere. The tropopause is defined according to the potential vorticity (PV) and potential temperature distribution. Annual simulations were performed with and without stratospheric O3 in the model to access the impact of stratospheric O3 on tropospheric O3 distribution. Our results show that surface O3 over the tropical marine boundary layer is dominated by in-situ photochemistry in the troposphere. The maintenance of the inter-hemispheric asymmetry in ozone over the extra-tropical marine boundary layer is dominated by the transport of O3 from the stratosphere. Comparisons between the model and the surface measurements show that the model without stratospheric O3 exhibits a hemispheric summer maximum, emphasizing the contributions of transport of O3 and O3 producing precursors from continental regions during the summer months, whilst no clear spring O3 maximum is found. About 50%-80% of O3 in the lower troposphere over the northern hemisphere mid-latitudes are photochemically produced during the northern hemisphere summer. About 20%-40% is due to tropospheric photochemistry in the lower troposphere during the northern hemisphere spring. We conclude that O3 transported from the stratosphere is the dominating factor for the spring O3 maximum over the extra-tropical latitudes, while the photochemical ozone production is the dominating factor for O3 over the tropical marine boundary layer environments and over the land surface emission areas.

An Improvement on Robust H<SUB>∞</SUB> Control for Uncertain Continuous-Time Descriptor Systems

Hung-Jen Lee,Shih-Wei Kau,Yung-Sheng Liu,Chun-Hsiung Fang,Jian-Liung Chen,Ming-Hung Tsai,Li Lee 대한전기학회 2006 International Journal of Control, Automation, and Vol.4 No.3

This paper proposes a new approach to solve robust H∞ control problems for uncertain continuous-time descriptor systems. Necessary and sufficient conditions for robust H∞ control analysis and design are derived and expressed in terms of a set of LMIs. In the proposed approach, the uncertainties are allowed to appear in all system matrices. Furthermore, a couple of assumptions that are required in earlier design methods are not needed anymore in the present one. The derived conditions also include several interesting results existing in the literature as special cases.

Does hyrax expansion therapy affect maxillary sinus volume? A cone-beam computed tomography report

Darsey, Drew M.,English, Jeryl D.,Kau, Chung H.,Ellis, Randy K.,Akyalcin, Sercan Korean Academy of Oral and Maxillofacial Radiology 2012 Imaging Science in Dentistry Vol.42 No.2

Purpose : The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Materials and Methods : Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Results : Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93mm(SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Conclusion : Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.

실리콘 결정면을 이용한 LCD-BLU용 도광판의 미세산란구조 형성

최가을,이준섭,송석호,오차환,김필수,lChoi Kau,Lee, Joon-Seob,Song, Seok-Ho,Oh Cha-Hwan,Kim, Pill-Soo 한국광학회 2005 한국광학회지 Vol.16 No.2

Luminous efficiency and uniformity in a LCD-BLU are mainly determined by fine scattering patterns formed on the light guide panel. We propose a novel fabrication method of 3-dimensional scattered patterns based on anisotropic etching of silicon wafers. Micro-pyramid patterns with 70.5 degree apex-angle and micro-prism patterns with 109.4 degree apex-angle can be self-constructed by the wet, anisotropic etching of (100) and (110) silicon wafers, respectively, and those patterns are easily duplicated by the PDMS replica process. Experimental results on spatial and angular distributions of irradiation from the light guide panel with the micro-pyramid patterns were very consistent with the calculation results. Surface roughness of the silicon-based micro-patterns is free from any artificial defects since the micro-patterns are inherently formed with silicon crystal surfaces. Therefore, we expect that the silicon based micro-patterning process makes it possible to fabricate perfect 3-dimensional micro-structures with crystal surface and apex angles, which may guarantee mass-reproduction of the light guide panels in LCD-BLU. LCD-BLU(liquid crystal device-back light unit)에 사용되는 도광판의 미세 산란패턴을 만드는 새로운 방법으로서, 실리콘 웨이퍼의 비등방 식각에 의해 자연적으로 형성되는 3차원 결정면 구조를 이용하는 방법을 제안하였다. 실리콘 3차원 결정면을 갖는 도광판과 프리즘 시트의 원판을 설계 및 제작하였고, casting 공정을 통해 PDMS 재질로 복제된 도광판을 제작하여 특성을 분석하였다. 측정 결과, 기존 인쇄형 도광판에 비해 실리콘피라미드 패턴의 도광판이 $10\%$ 증가된 정면 휘도 효율을 가질 수 있음을 실험적으로 검증하였다.

Does hyrax expansion therapy affect maxillary sinus volume? : A cone-beam computed tomography report

Drew M. Darsey,Jeryl D. English,Chung H. Kau,Randy K. Ellis,Sercan Akyalcin 대한구강악안면방사선학회 2012 Imaging Science in Dentistry Vol.42 No.2

Objectives: The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Materials and Methods: Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Results: Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93 mm (SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Conclusions: Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.