scholarly journals Rapid evidence review to inform safe return to campus in the context of coronavirus disease 2019 (COVID-19)

2022 ◽  
Vol 6 ◽  
pp. 282
Author(s):  
Trisha Greenhalgh ◽  
Aris Katzourakis ◽  
Tristram D. Wyatt ◽  
Stephen Griffin
Keyword(s):  
Online Education ◽  
High Efficiency ◽  
Control Measures ◽  
Transmission Risk ◽  
Source Control ◽  
Activity Levels ◽  
Engineering Controls ◽  
Narrative Methods ◽  
Wide Range ◽  
Lateral Flow Tests

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted predominantly through the air in crowded and unventilated indoor spaces, especially among unvaccinated people. Universities and colleges are potential settings for its spread. Methods: An interdisciplinary team from public health, virology, and biology used narrative methods to summarise and synthesise evidence on key control measures, taking account of mode of transmission. Results: Evidence from a wide range of primary studies supports six measures.  Vaccinate (aim for > 90% coverage and make it easy to get a jab). Require masks indoors, especially in crowded settings. If everyone wears well-fitting cloth masks, source control will be high, but for maximum self-protection, respirator masks should be worn.  Masks should not be removed for speaking or singing. Space people out by physical distancing (but there is no “safe” distance because transmission risk varies with factors such as ventilation, activity levels and crowding), reducing class size (including offering blended learning), and cohorting (students remain in small groups with no cross-mixing). Clean indoor air using engineering controls—ventilation (while monitoring CO2 levels), inbuilt filtration systems, or portable air cleaners fitted with high efficiency particulate air [HEPA] filters). Test asymptomatic staff and students using lateral flow tests, with tracing and isolating infectious cases when incidence of coronavirus disease 2019 (COVID-19) is high. Support clinically vulnerable people to work remotely. There is no direct evidence to support hand sanitising, fomite controls or temperature-taking. There was no evidence that freestanding plastic screens, face visors and electronic air-cleaning systems are effective. Conclusions: The above evidence-based measures should be combined into a multi-faceted strategy to maximise both student safety and the continuation of in-person and online education provision. Those seeking to provide a safe working and learning environment should collect data (e.g. CO2 levels, room occupancy) to inform their efforts.

scholarly journals Rapid evidence review to inform safe return to campus in the context of coronavirus disease 2019 (COVID-19)

2021 ◽  
Vol 6 ◽  
pp. 282
Author(s):  
Trisha Greenhalgh ◽  
Aris Katzourakis ◽  
Tristram D. Wyatt ◽  
Stephen Griffin
Keyword(s):  
Online Education ◽  
High Efficiency ◽  
Control Measures ◽  
Transmission Risk ◽  
Source Control ◽  
Activity Levels ◽  
Engineering Controls ◽  
Narrative Methods ◽  
Wide Range ◽  
Lateral Flow Tests

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted predominantly through the air in crowded and unventilated indoor spaces among unvaccinated people. Universities and colleges are potential settings for its spread. Methods: An interdisciplinary team from public health, virology, and biology used narrative methods to summarise and synthesise evidence on key control measures, taking account of mode of transmission. Results: Evidence from a wide range of primary studies supports six measures. Vaccinate (aim for > 90% coverage and make it easy to get a jab). Require masks indoors, especially in crowded settings. If everyone wears well-fitting cloth masks, source control will be high, but for maximum self-protection, respirator masks should be worn.  Masks should not be removed for speaking or singing. Space people out by physical distancing (but there is no “safe” distance because transmission risk varies with factors such as ventilation, activity levels and crowding), reducing class size (including offering blended learning), and cohorting (students remain in small groups with no cross-mixing). Clean indoor air using engineering controls—ventilation (while monitoring CO2 levels), inbuilt filtration systems, or portable air cleaners fitted with high efficiency particulate air [HEPA] filters). Test asymptomatic staff and students using lateral flow tests, with tracing and isolating infectious cases when incidence of coronavirus disease 2019 (COVID-19) is high. Support clinically vulnerable people to work remotely. There is no direct evidence to support hand sanitising, fomite controls or temperature-taking. There is evidence that freestanding plastic screens, face visors and electronic air-cleaning systems are ineffective. Conclusions: The above six evidence-based measures should be combined into a multi-faceted strategy to maximise both student safety and the continuation of in-person and online education provision. Staff and students seeking to negotiate a safe working and learning environment should collect data (e.g. CO2 levels, room occupancy) to inform conversations.

scholarly journals Knowledge Economy: Model Construction and Development Trend of Online Education

2022 ◽  
Vol 6 (1) ◽  
pp. 40-46
Author(s):  
Junjie Liu ◽  
Maxim Chernyaev
Keyword(s):  
Online Education ◽  
Knowledge Economy ◽  
High Efficiency ◽  
Development Trend ◽  
Internet Technology ◽  
Model Construction ◽  
Teaching Resources ◽  
Education Services ◽  
Wide Range ◽  
The Moment

In regard to knowledge economy, the current concept in the model construction of online education, including distance education and online learning, generally refers to a kind of network-based learning behavior, similar to the concept of online training. Compared with traditional offline education methods, through the application of information technology and internet technology for content dissemination and rapid learning, online education has the characteristics of high efficiency, convenience, low threshold, and rich teaching resources. Online education covers a wide range of people, different forms of learning, and its classification methods are more diverse. Online education services are the fastest growing field of education informatization. At the moment, the most pressing problems include effectively integrating educational resources with internet technology, launching online education services and products that are highly interactive and would encourage personalized learning, increasing user stickiness, as well as avoiding trend-following and conceptualized investment.

scholarly journals An Assessment of the Robustness of the COSHH-Essentials (C-E) Target Airborne Concentration Ranges 15 Years on, and Their Usefulness for Determining Control Measures

2017 ◽  
Vol 61 (3) ◽  
pp. 270-283 ◽  
Author(s):  
Nicholas P. Vaughan ◽  
Rajadurai Rajan-Sithamparanadarajah
Keyword(s):  
Health Hazard ◽  
Good Practice ◽  
Health And Safety ◽  
Control Measures ◽  
Hazardous Substances ◽  
The European Union ◽  
Engineering Controls ◽  
Control Banding ◽  
Airborne Concentration ◽  
Wide Range

Abstract The Health and Safety Executive (HSE) in Great Britain (GB), in association with its stakeholders, developed the Control of Substances Hazardous to Health (COSHH)-Essentials (C-E) control banding tool in 1998. The objective was to provide a simple tool for employers, particularly small and medium-sized enterprises (SMEs), to help select and apply appropriate measures for the adequate control of exposure to hazardous substances. The tool used hazard classification information (R-phrases) to assign substances to one of five health hazard groups, each with its respective ‘target airborne concentration range’. The validity of the allocation of substances to a target airborne concentration range was demonstrated at the time using 111 substances that had a current health-based Occupational Exposure Limit (OEL) in GB. The C-E control banding approach remains an important tool to complement exposure assessment/monitoring and the selection and use of suitable control measures for hazardous substances. These include engineering controls and personal protective equipment (PPE). The C-E based control banding approach has been adopted around the world. This paper extends the original validation exercise, using a greater number of chemical substances, to establish whether the target airborne concentration ranges remain appropriate. This is of particular interest in light of the introduction of the Globally Harmonized System (GHS) for classification, in which R-phrases have now been replaced by hazard-statements (H-statements). The validation exercise includes substances with OELs published by nine bodies internationally; and the Derived No-Effect Levels (DNELs) assigned by registrants under the European Union—Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Regulations. When compared against 8-hour TWA OELs for 850 substances drawn from nine bodies and a limited number of DNELS, the C-E target airborne concentration ranges remain valid. This comparative work also informs a wider consideration around the practicality and the applicability of the C-E generic approach to facilitate the implementation of good practice control for a wide range of substances (more than 95%) which do not have any recognized OEL.

Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives Through a Combination of 8-Aminoquinoline Directed C–H Arylations and Transamidations

2019 ◽  
Author(s):  
Michael Oschmann ◽  
Linus Johansson Holm ◽  
Oscar Verho
Keyword(s):  
Small Molecule ◽  
High Efficiency ◽  
Synthetic Strategy ◽  
Small Molecule Screening ◽  
Physiological Properties ◽  
Wide Range ◽  
Directing Group ◽  
Synthetic Sequence

Benzofurans are everywhere in nature and they have been extensively studied by medicinal chemists over the years because of their chemotherapeutic and physiological properties. Herein, we describe a strategy that can be used to access elaborate benzo-2-carboxamide derivatives, which involves a synthetic sequence of 8-aminoquinoline directed C–H arylations followed by transamidations. For the directed C–H arylations, Pd catalysis was used to install a wide range of aryl and heteroaryl substituents at the C3 position of the benzofuran scaffold in high efficiency. Directing group cleavage and further diversification of the C3-arylated benzofuran products were then achieved in a single synthetic operation through the utilization of a two-step transamidation protocol. By bocylating the 8-aminoquinoline amide moiety of these products, it proved possible to activate them towards aminolysis with different amine nucleophiles. Interestingly, this aminolysis reaction was found to proceed efficiently without the need of any additional catalyst or additive. Given the high efficiency and modularity of this synthetic strategy, it constitute a very attractive approach for generating structurally-diverse collections of benzofuran derivatives for small molecule screening.

COVID-19 Outbreak Prediction with Machine Learning

2020 ◽  
Author(s):  
Sina Faizollahzadeh Ardabili ◽  
Amir Mosavi ◽  
Pedram Ghamisi ◽  
Filip Ferdinand ◽  
Annamaria R. Varkonyi-Koczy ◽  
...  
Keyword(s):  
Machine Learning ◽  
Prediction Models ◽  
Fuzzy Inference ◽  
Control Measures ◽  
Future Research ◽  
Complex Nature ◽  
Inference System ◽  
Wide Range ◽  
Standard Models ◽  
High Level

Several outbreak prediction models for COVID-19 are being used by officials around the world to make informed-decisions and enforce relevant control measures. Among the standard models for COVID-19 global pandemic prediction, simple epidemiological and statistical models have received more attention by authorities, and they are popular in the media. Due to a high level of uncertainty and lack of essential data, standard models have shown low accuracy for long-term prediction. Although the literature includes several attempts to address this issue, the essential generalization and robustness abilities of existing models needs to be improved. This paper presents a comparative analysis of machine learning and soft computing models to predict the COVID-19 outbreak as an alternative to SIR and SEIR models. Among a wide range of machine learning models investigated, two models showed promising results (i.e., multi-layered perceptron, MLP, and adaptive network-based fuzzy inference system, ANFIS). Based on the results reported here, and due to the highly complex nature of the COVID-19 outbreak and variation in its behavior from nation-to-nation, this study suggests machine learning as an effective tool to model the outbreak. This paper provides an initial benchmarking to demonstrate the potential of machine learning for future research. Paper further suggests that real novelty in outbreak prediction can be realized through integrating machine learning and SEIR models.

To the 70th anniversary of World Meteorological Organization. Scientific and technical cooperation of Hydrometeorological Center of the USSR/Russia in the Programs of World Meteorological Organization

2020 ◽  
pp. 117-138
Author(s):  
S.V. Borshch ◽  
◽  
R.M. Vil’fand ◽  
D.B. Kiktev ◽  
V.M. Khan ◽  
...  
Keyword(s):  
Environmental Monitoring ◽  
High Efficiency ◽  
World Meteorological Organization ◽  
70Th Anniversary ◽  
Technical Level ◽  
Technical Cooperation ◽  
Wide Range

The paper presents the summary and results of long-term and multi-faceted experience of international scientific and technical cooperation of Hydrometeorological Center of Russia in the field of hydrometeorology and environmental monitoring within the framework of WMO programs, which indicates its high efficiency in performing a wide range of works at a high scientific and technical level. Keywords: World Meteorological Organization, major WMO programs, representatives of Hydrometeorological Center of Russia in WMO

Integrated Design and Multi-Objective Optimization of a Single Stage Heat-Pump Turbocompressor

2013 ◽  
Author(s):  
J. Schiffmann
Keyword(s):  
Design Optimization ◽  
High Efficiency ◽  
Integrated Design ◽  
Heat Pumps ◽  
Small Scale ◽  
Multi Objective Optimization ◽  
Design Constraints ◽  
Multi Objective ◽  
Wide Range ◽  
Standard Design

Small scale turbomachines in domestic heat pumps reach high efficiency and provide oil-free solutions which improve heat-exchanger performance and offer major advantages in the design of advanced thermodynamic cycles. An appropriate turbocompressor for domestic air based heat pumps requires the ability to operate on a wide range of inlet pressure, pressure ratios and mass flows, confronting the designer with the necessity to compromise between range and efficiency. Further the design of small-scale direct driven turbomachines is a complex and interdisciplinary task. Textbook design procedures propose to split such systems into subcomponents and to design and optimize each element individually. This common procedure, however, tends to neglect the interactions between the different components leading to suboptimal solutions. The authors propose an approach based on the integrated philosophy for designing and optimizing gas bearing supported, direct driven turbocompressors for applications with challenging requirements with regards to operation range and efficiency. Using previously validated reduced order models for the different components an integrated model of the compressor is implemented and the optimum system found via multi-objective optimization. It is shown that compared to standard design procedure the integrated approach yields an increase of the seasonal compressor efficiency of more than 12 points. Further a design optimization based sensitivity analysis allows to investigate the influence of design constraints determined prior to optimization such as impeller surface roughness, rotor material and impeller force. A relaxation of these constrains yields additional room for improvement. Reduced impeller force improves efficiency due to a smaller thrust bearing mainly, whereas a lighter rotor material improves rotordynamic performance. A hydraulically smoother impeller surface improves the overall efficiency considerably by reducing aerodynamic losses. A combination of the relaxation of the 3 design constraints yields an additional improvement of 6 points compared to the original optimization process. The integrated design and optimization procedure implemented in the case of a complex design problem thus clearly shows its advantages compared to traditional design methods by allowing a truly exhaustive search for optimum solutions throughout the complete design space. It can be used for both design optimization and for design analysis.

scholarly journals Low Power Cusped Field Thruster Developed for the Space-Borne Gravitational Wave Detection Mission in China

2021 ◽  
Vol 11 (14) ◽  
pp. 6549
Author(s):  
Hui Liu ◽  
Ming Zeng ◽  
Xiang Niu ◽  
Hongyan Huang ◽  
Daren Yu
Keyword(s):  
Low Power ◽  
Gravitational Wave ◽  
Attitude Control ◽  
High Efficiency ◽  
Experimental Investigations ◽  
Attitude Control System ◽  
Gravitational Wave Detection ◽  
Wave Detection ◽  
Wide Range ◽  
Institute Of Technology

The microthruster is the crucial device of the drag-free attitude control system, essential for the space-borne gravitational wave detection mission. The cusped field thruster (also called the High Efficiency Multistage Plasma Thruster) becomes one of the candidate thrusters for the mission due to its low complexity and potential long life over a wide range of thrust. However, the prescribed minimum of thrust and thrust noise are considerable obstacles to downscaling works on cusped field thrusters. This article reviews the development of the low power cusped field thruster at the Harbin Institute of Technology since 2012, including the design of prototypes, experimental investigations and simulation studies. Progress has been made on the downscaling of cusped field thrusters, and a new concept of microwave discharge cusped field thruster has been introduced.

scholarly journals Fracture risk across a wide range of physical activity levels, from sedentary individuals to elite athletes

Bone ◽  
2021 ◽  
pp. 116128
Author(s):  
Karl Stattin ◽  
Jonas Höijer ◽  
Ulf Hållmarker ◽  
John A. Baron ◽  
Susanna C. Larsson ◽  
...  
Keyword(s):  
Physical Activity ◽  
Fracture Risk ◽  
Elite Athletes ◽  
Activity Levels ◽  
Wide Range ◽  
Physical Activity Levels

scholarly journals Microbial antagonists against plant pathogens in Iran: A review

2020 ◽  
Vol 5 (1) ◽  
pp. 404-440 ◽  
Author(s):  
Mehrdad Alizadeh ◽  
Yalda Vasebi ◽  
Naser Safaie
Keyword(s):  
Biological Control ◽  
Chemical Control ◽  
Plant Disease ◽  
Plant Pathogens ◽  
Plant Diseases ◽  
Agricultural Products ◽  
Control Measures ◽  
Wide Range ◽  
Plant Disease Management ◽  
Published Research

AbstractThe purpose of this article was to give a comprehensive review of the published research works on biological control of different fungal, bacterial, and nematode plant diseases in Iran from 1992 to 2018. Plant pathogens cause economical loss in many agricultural products in Iran. In an attempt to prevent these serious losses, chemical control measures have usually been applied to reduce diseases in farms, gardens, and greenhouses. In recent decades, using the biological control against plant diseases has been considered as a beneficial and alternative method to chemical control due to its potential in integrated plant disease management as well as the increasing yield in an eco-friendly manner. Based on the reported studies, various species of Trichoderma, Pseudomonas, and Bacillus were the most common biocontrol agents with the ability to control the wide range of plant pathogens in Iran from lab to the greenhouse and field conditions.

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