scholarly journals Portable HEPA Purifiers to Eliminate Airborne SARS-CoV-2: A Systematic Review

2021 ◽  
pp. 019459982110226
Author(s):  
David T. Liu ◽  
Katie M. Philips ◽  
Marlene M. Speth ◽  
Gerold Besser ◽  
Christian A. Mueller ◽  
...  

Objective Current epidemiologic predictions of COVID-19 suggest that SARS-CoV-2 mitigation strategies must be implemented long-term. In-office aerosol-generating procedures pose a risk to staff and patients while necessitating examination room shutdown to allow aerosol decontamination by indwelling ventilation. This review summarizes the current state of knowledge on portable high-efficiency particulate air (HEPA) purifiers’ effectiveness in eliminating airborne SARS-CoV-2 from indoor environments. Data Sources Medline, Embase, Cochrane Databases, and the World Health Organization’s COVID-19 Global Literature on Coronavirus Disease. Review Methods Data sources were systematically searched for original English-language published studies indexed up to January 14, 2021 per the following search strategy: (“HEPA” OR “High-efficiency” OR “High-efficiency particulate air” OR “Efficiency particulate” OR “Purifier” OR “Filter” OR “Cleaner” OR “Filtration”) AND (“COVID” OR “COVID-19” OR “SARS-CoV-2” OR “Coronavirus”). Additional relevant studies were identified by searching the reference lists of included articles. Results Eleven published studies have evaluated the effectiveness of portable HEPA purifiers in eliminating airborne SARS-CoV-2 with relevantly sized surrogate particles. Ten studies evaluated aerosols and submicron particles similar in size to SARS-CoV-2 virions. In all studies, portable HEPA purifiers were able to significantly reduce airborne SARS-CoV-2-surrogate particles. The addition of portable HEPA purifiers augmented other decontamination strategies such as ventilation. Conclusion Experimental studies provide evidence for portable HEPA purifiers’ potential to eliminate airborne SARS-CoV-2 and augment primary decontamination strategies such as ventilation. Based on filtration rates, additional air exchanges provided by portable HEPA purifiers may be calculated and room shutdown times potentially reduced after aerosol-generating procedures.

2017 ◽  
Vol 157 (6) ◽  
pp. 948-954 ◽  
Author(s):  
Jad Jabbour ◽  
Lauren M. North ◽  
David Bougie ◽  
Thomas Robey

Objectives To describe the present understanding of birth trauma–related vocal fold immobility and quantitatively compare it with idiopathic congenital vocal fold immobility to explore whether it is a discrete entity. Data Sources PubMed, Ovid, and Cochrane databases. Review Methods English-language, observational, or experimental studies involving infants with idiopathic congenital or birth trauma–related vocal fold immobility were included. Data from these studies were pooled with our institution’s vocal fold immobility database, with the resultant idiopathic congenital and birth trauma cohorts compared regarding patterns and outcomes of immobility. Results The search returned 288 articles, with 24 meeting inclusion criteria. Of studies reviewing all-cause immobility, 8 of 9 (88.9%) identified birth trauma as an etiology, although birth trauma definitions and proposed mechanisms of immobility varied. The study subjects, combined with our institution’s database, yielded 188 idiopathic congenital and 113 birth trauma cases. Compared with idiopathic congenital cases, birth trauma cases had a higher proportion of unilateral immobility (72 of 113 [63.7%] vs 52 of 188 [27.7%], P < .001) and rate of resolution (41 of 51 [80.4%] vs 91 of 159 [57.2%], P = .003). Resolution occurred in 24 of 26 (91.3%) unilateral and 17 of 25 (68.0%) bilateral birth trauma cases and in 30 of 40 (75.0%) unilateral and 59 of 109 (54.1%) bilateral idiopathic congenital cases ( P = .11 and .20, respectively). Conclusion While the definition and mechanism of birth trauma–related vocal fold immobility warrant further investigation, these findings suggest that it is distinct from idiopathic congenital vocal fold immobility, with a unique presentation and potentially more favorable outcomes. This can inform counseling and management for infants with otherwise unexplained immobility but known birth trauma.


1969 ◽  
Vol 8 (02) ◽  
pp. 53-59 ◽  
Author(s):  
John Mayne

For the past several years, experimental studies have been undertaken at the Mayo Clinic to evaluate the feasibility of utilizing electronic data processing to handle medical information, especially the medical information which makes up a medical record. We have experimented with automated techniques for collecting and storing medical-history data, specifically with techniques for computer generation and processing of health questionnaires, for computer-controlled administration of health questionnaires, and for computer-controlled entry and retrieval of medical-history data directly by physicians in ordinary English language by use of a video-screen and light-pen computer terminal.The questionnaire studies are concerned with ways of entering into computer storage medical-history data obtained from patients without physician involvement; the video-screen studies are concerned with entry into computer storage of medical-history data obtained by physicians in their interview with the patient. The paper describes our experiences in these studies.


2020 ◽  
Vol 22 (1) ◽  
pp. 32-45
Author(s):  
Emanuela Martina ◽  
Federico Diotallevi ◽  
Tommaso Bianchelli ◽  
Matteo Paolinelli ◽  
Annamaria Offidani

Background: Chronic Spontaneous Urticaria (CSU) is a disease characterized by the onset of wheals and/or angioedema over 6 weeks. The pathophysiology for CSU is very complex, involving mast cells and basophils with a multitude of inflammatory mediators. For many years the treatment of CSU has been based on the use of antihistamines, steroids and immunosuppressive agents with inconstant and frustrating results. The introduction of omalizumab, the only licensed biologic for antihistamine- refractory CSU, has changed the management of the disease. Objective: The aim of this article is to review the current state of the art of CSU, the real-life experience with omalizumab and the promising drugs that are under development. Methods:: An electronic search was performed to identify studies, case reports, guidelines and reviews focused on the new targets for the treatment of chronic spontaneous urticaria, both approved or under investigation. The search was limited to articles published in peer-reviewed journals in the English Language in the PubMed database and trials registered in Clinicaltrials.gov. Results:: Since the advent of omalizumab, the search for new therapies for chronic spontaneous urticaria has had a new impulse. Anti-IgE drugs will probably still be the cornerstone of therapy, but new targets may prove effective in syndromic urticaria or refractory cases. Conclusion:: Although omalizumab has been a breakthrough in the treatment of CSU, many patients do not completely get benefit and even require more effective treatments. Novel drugs are under investigation with promising results.


2020 ◽  
Vol 15 (5) ◽  
pp. 35-55
Author(s):  
N.P. STARYKH ◽  
◽  
A.V. EGOROVA ◽  

The purpose of the article is to analyze the current state of healthcare in Russia. Scientific novelty of the study: the authors suggest that the efficiency of the health care system depends on the state of such indicators of public health as life expectancy and healthy life expectancy. Life expectancy is an integrated demographic indicator that characterizes the number of years that a person would live on average, provided that the age-specific mortality rate of a generation would be at the level for which the indicator was calculated throughout life. The indicator ‘healthy life expectancy’ is formed by subtracting the number of years of unhealthy life (due to chronic diseases, disabilities, mental and behavioral disorders, etc.) from the life expectancy indicator. Results: the article presents an analysis of the current state of Russian healthcare based on statistical data provided by the Federal State Statistics Service, the World Health Organization, and world rankings. Attention is focused on the perceptions of Russians about the quality of medical services and Russian healthcare. Conclusions about the current state of health care in Russia are formulated by the authors, based on a secondary analysis of statistical data, as well as data from sociological research presented by leading Russian sociological centers.


Author(s):  
Jeremy Youde

While Chapter 3 focuses primarily on the evolution of global health governance, Chapter 4 pays more attention to its contemporary manifestation as a secondary institution within international society. This chapter discusses the current state of the global health governance architecture—who the important actors are, how they operate, how they have changed over the past twenty-five years, and how they illustrate the fundamental beliefs and attitudes within the global health governance system. In particular, the chapter discusses the relative balance between state-based and non-state actors, as well as public versus private actors. This chapter highlights five key players within contemporary global health governance: states; the World Health Organization; multilateral funding agencies; public–private partnerships; and non-state and private actors


2021 ◽  
Vol 63 (1) ◽  
Author(s):  
Katy Satué ◽  
Juan Carlos Gardon ◽  
Ana Muñoz

AbstractMyeloid disorders are conditions being characterized by abnormal proliferation and development of myeloid lineage including granulocytes (neutrophils, eosinophils and basophils), monocytes, erythroids, and megakaryocytes precursor cells. Myeloid leukemia, based on clinical presentation and proliferative rate of neoplastic cells, is divided into acute (AML) and myeloproliferative neoplasms (MPN). The most commonly myeloid leukemia reported in horses are AML-M4 (myelomonocytic) and AML-M5 (monocytic). Isolated cases of AML-M6B (acute erythroid leukemia), and chronic granulocytic leukemia have also been reported. Additionally, bone marrow disorders with dysplastic alterations and ineffective hematopoiesis affecting single or multiple cell lineages or myelodysplastic diseases (MDS), have also been reported in horses. MDSs have increased myeloblasts numbers in blood or bone marrow, although less than 20%, which is the minimum level required for diagnosis of AML. This review performed a detailed description of the current state of knowlegde of the myeloproliferative disorders in horses following the criteria established by the World Health Organization.


Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 574
Author(s):  
Ana Vafadar ◽  
Ferdinando Guzzomi ◽  
Kevin Hayward

Air heat exchangers (HXs) are applicable in many industrial sectors because they offer a simple, reliable, and cost-effective cooling system. Additive manufacturing (AM) systems have significant potential in the construction of high-efficiency, lightweight HXs; however, HXs still mainly rely on conventional manufacturing (CM) systems such as milling, and brazing. This is due to the fact that little is known regarding the effects of AM on the performance of AM fabricated HXs. In this research, three air HXs comprising of a single fin fabricated from stainless steel 316 L using AM and CM methods—i.e., the HXs were fabricated by both direct metal printing and milling. To evaluate the fabricated HXs, microstructure images of the HXs were investigated, and the surface roughness of the samples was measured. Furthermore, an experimental test rig was designed and manufactured to conduct the experimental studies, and the thermal performance was investigated using four characteristics: heat transfer coefficient, Nusselt number, thermal fluid dynamic performance, and friction factor. The results showed that the manufacturing method has a considerable effect on the HX thermal performance. Furthermore, the surface roughness and distribution, and quantity of internal voids, which might be created during and after the printing process, affect the performance of HXs.


Author(s):  
Parviz Enany ◽  
Oleksandr Shevchenko ◽  
Carsten Drebenstedt

AbstractThis paper presents experimental studies on the optimization of air–water flow in an airlift pump. Airlift pumps use compressed gas to verticall transport liquids and slurries. Due to the lack of theoretical equations for designing and predicting flow regimes, experimental investigations must be carried out to find the best condition to operate an airlift pump at high efficiency. We used a new air injection system and different submergence ratios to evaluate the output of a simple pump for vertical displacement of water in an underground mine. The tests were carried out in a new device with 5.64 m height and 10.2 cm circular riser pipe. Three air-jacket pipes, at different gas flows in the range of 0.002–0.09 m3/s were investigated with eight submergence ratios. It was found that with the same air flow rate, the most efficient flow of water was achieved when an air jacket with 3 mm diameter holes was used with a submergence ratio between 0.6 and 0.75. In addition, a comparison of practical results with two theoretical models proposed by other investigators showed that neither was able to accurately predict airlift performance in air–water flow mode.


Author(s):  
Grigoris Gerotziafas ◽  
Mariella Catalano ◽  
Ioannis Theodorou ◽  
Patrick van Dreden ◽  
Vincent Marechal ◽  
...  

One year after the declaration of the COVID-19 pandemic by the World Health Organization (WHO) and despite the implementation of mandatory physical barriers and social distancing, humanity remains challenged by a long-lasting and devastating public health crisis. Non-pharmacological interventions (NPI) are efficient mitigation strategies. The success of these intense NPI is dependent on the approval and commitment of the population. The launch of a mass vaccination program in many countries in late December 2020 with mRNA vaccines, adenovirus-based vaccines, and inactivated virus vaccines has generated hope for the end of the pandemic. Current issues: The continuous appearance of new pathogenic viral strains and the ability of vaccines to prevent infection and transmission raise important concerns as we try to achieve community immunity against SARS-CoV-2 and its variants. The need of a second and even third generation of vaccines and the possibility of potentially harmful side-effects of the vaccines (i.e. venous thromboembolism ) have already been acknowledged. Perspectives: There is a critical and urgent need for a balanced and integrated strategy for the management of the COVID-19 outbreaks organized on three axes: (1) Prevention of the SARS-CoV-2 infection, (2) Detection and early diagnosis of patients at risk of disease worsening, and (3) Anticipation of medical care (PDA). Conclusion: The “PDA strategy” integrated into state policy for the support and expansion of health systems and introduction of digital organization (i.e. telemedicine, artificial intelligence and machine learning technology) is of major importance for the preservation of citizens’ health and life world-wide.


Author(s):  
Anatoli A. Borissov ◽  
Alexander A. Borissov ◽  
Kenneth K. Kramer

Each year, the users in the U.S. alone spend over $100 billion on various type of engines to produce power — electrical, mechanical, and thermal. Despite technological advances, most all of these power generation systems have only been fine tuned: the engine efficiencies may have been improved slightly, but the underlying thermodynamic principles have not been modified to effect a drastic improvement. The result is that most engines in service today suffer from two major problems: low fuel efficiency and emission of high levels of polluting gases in the exhaust gases. The current state of propulsion engines or distributed generation technologies using heat engines shows an average efficiency of between 20% and 40%. These low efficiencies in a high–cost energy market indicate a great need for more efficient technologies. This paper describes a new method of achieving a very high efficiency, namely optimizing every stage of the thermodynamic process-Brayton cycle. Two modified processes, such as isothermal compression and recuperation, add about 35% efficiency to the conventional Brayton cycle, making 60% efficiency for modified Brayton cycle. By utilizing a positive displacement compressor and expander with a novel vortex combustion chamber and a vortex recuperator, high levels of efficiency with low emissions and noise are possible. The prototype engine with low RPM and high torque has been built which use continuous combustion of different fuels under a constant pressure. First results of the engine’s components testing are presented.


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