scholarly journals Study of Filtration in Polyethylene Fibers used in Masks for Protection Against SARS-CoV-2 via Luminescent Aerosolized Silicon Nanoparticles

2021 ◽  
Author(s):  
Ayman Rezk ◽  
Juveiriah Ashraf ◽  
Wafa Alnaqbi ◽  
Sabina Abdul Hadi ◽  
Ghada Dushaq ◽  
...  
Keyword(s):  
Silicon Nanoparticles ◽  
Optical Microscope ◽  
The Novel ◽  
Filtration Process ◽  
Fiber Network ◽  
Spider Web ◽  
Si Nanoparticle ◽  
Si Nanoparticles ◽  
Novel Coronavirus ◽  
Polyethylene Fibers

Abstract Commercial polyethylene (PE) fiber-based masks are currently used as personal filters for protection against various microorganisms. Due to the coronavirus (SARS-CoV-2) pandemic of 2020, the use of masks has become the critical mechanism in reducing the spread. The PE mask filter uses a sieve (geometry) in a spider web fashion to filter out microorganisms using Van der Waals atomic forces. However, the non-geometrical part of the filtration process is not fully understood. In this work, we utilized luminescent ultra-small silicon nanoparticles, which are Si-H or/and Si-OH terminated to examine how the filter operates at a chemical level. The particles were sprayed onto the fiber network by an atomizer and we used scanning electron microscopy (SEM), optical microscope and fluorescence spectroscopy under UV radiation. The images and measurements clearly showed that the Si nanoparticles bonded to the PE fiber network. The results were analyzed in terms of chemical bonding between Si nanoparticle and fiber. Our findings suggest that the PE fibers could act as a chemical filter via hydrogen or hydrolysis–based bonding or via Si-C bonding, which is complementary to their physical filtration ability via the geometric sieve process. Moreover, the results indicate that the filter would be effective against the novel coronavirus, not only by the geometrical sieve but can be additionally enhanced as a chemical filter by allowing the amine, carboxyl and hydroxyl function groups of the virus to attach to fibers via C-N and C-O bonds.

Tomographic Study of Silicon Nanoparticles in Nanocrystalline Non-Volatile Flash Memory Devices by EFTEM

2012 ◽  
Author(s):  
YongKai Zhou ◽  
Jie Zhu ◽  
AnYan Du ◽  
YouNan Hua ◽  
ZhiQiang Mo ◽  
...  
Keyword(s):  
Flash Memory ◽  
Silicon Nanoparticles ◽  
Tomographic Reconstruction ◽  
Memory Devices ◽  
Plan View ◽  
Si Nanoparticle ◽  
Thin Film Layer ◽  
Si Nanoparticles ◽  
Key Factor ◽  
Film Layer

Abstract The distribution of Si nanoparticles, both dimensional and spatial, is a key factor affecting the performance of non-volatile flash memory devices. A new FIB method has been developed to prepare ultra-thin plan view specimens, containing only the Si nanoparticle matrix thin film layer, from fully processed nanocrystalline flash memory devices. The morphology and distribution of Si nanoparticles were then studied by EFTEM 3D tomographic reconstruction.

scholarly journals Optical Properties of Silicon Nanoparticles Prepared by Laser Ablation Method in Various Media

2014 ◽  
Vol 24 (3S1) ◽  
pp. 143-148
Author(s):  
Chu Anh Tuan ◽  
Nguyen Thi Thu Trang ◽  
Le Anh Tu ◽  
Duong Thi Giang ◽  
Pham Hong Duong ◽  
...  
Keyword(s):  
Optical Properties ◽  
Silicon Nanoparticles ◽  
Peak Position ◽  
Quenching Effect ◽  
Laser Ablation Method ◽  
Silicon Target ◽  
Si Nanoparticle ◽  
Si Nanoparticles ◽  
532 Nm ◽  
Si Wafer

Bright photoluminescent silicon nanoparticles were successfully fabricated from porous silicon target in air and n-hexane using 532 nm line of YAG:Nd pulsed laser. The whole procedure was carried out at room temperature, in atmosphere. The morphology and composition of as-synthesized nanoparticles were characterized by SEM and EDS measurements. Their optical properties were investigated. The PL peak position of the as-synthesized Si nanoparticle ablated in air is slightly blue-shifted in comparison with those ablated in n-hexane, while it was almost no change of peak position of Si nanoparticles fabricated from p-Si in hexane and original p-Si wafer target. In contrast to PL intensity quenching of original p-Si sample and particles produced in air, those produced in n-hexane solvent exhibited an enhancement. The presence of dangling bonds or energy transfer from excited Si particles to oxygen molecules on the surface can be the cause of the quenching effect.

Comparative docking of SARS-CoV-2 receptors antagonists from repurposing drugs

2020 ◽  
Author(s):  
Micael Davi Lima de Oliveira ◽  
Kelson Mota Teixeira de Oliveira
Keyword(s):  
World Health Organisation ◽  
World Health ◽  
Lung Cells ◽  
The Novel ◽  
High Modulation ◽  
Main Protease ◽  
The World ◽  
Novel Coronavirus ◽  
Viral Receptors ◽  
Theoretical Results

According to the World Health Organisation, until 16 June, 2020, the number of confirmed and notified cases of COVID-19 has already exceeded 7.9 million with approximately 434 thousand deaths worldwide. This research aimed to find repurposing antagonists, that may inhibit the activity of the main protease (Mpro) of the SARS-CoV-2 virus, as well as partially modulate the ACE2 receptors largely found in lung cells, and reduce viral replication by inhibiting Nsp12 RNA polymerase. Docking molecular simulations were performed among a total of 60 structures, most of all, published in the literature against the novel coronavirus. The theoretical results indicated that, in comparative terms, paritaprevir, ivermectin, ledipasvir, and simeprevir, are among the most theoretical promising drugs in remission of symptoms from the disease. Furthermore, also corroborate indinavir to the high modulation in viral receptors. The second group of promising drugs includes remdesivir and azithromycin. The repurposing drugs HCQ and chloroquine were not effective in comparative terms to other drugs, as monotherapies, against SARS-CoV-2 infection.

SARS-COV2 virus and Coronavirus disease (COVID-19)

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 977-982
Author(s):  
Mohamed J. Saadh ◽  
Bashar Haj Rashid M ◽  
Roa’a Matar ◽  
Sajeda Riyad Aldibs ◽  
Hala Sbaih ◽  
...  
Keyword(s):  
Close Contact ◽  
Antiviral Agents ◽  
Health Concern ◽  
The Novel ◽  
Global Public Health ◽  
Fatal Disease ◽  
Mild Disease ◽  
Life Threatening ◽  
Novel Coronavirus

SARS-COV2 virus causes Coronavirus disease (COVID-19) and represents the causative agent of a potentially fatal disease that is of great global public health concern. The novel coronavirus (2019) was discovered in 2019 in Wuhan, the market of the wet animal, China with viral pneumonia cases and is life-threatening. Today, WHO announces COVID-19 outbreak as a pandemic. COVID-19 is likely to be zoonotic. It is transmitted from bats as intermediary animals to human. Also, the virus is transmitted from human to human who is in close contact with others. The computerized tomographic chest scan is usually abnormal even in those with no symptoms or mild disease. Treatment is nearly supportive; the role of antiviral agents is yet to be established. The SARS-COV2 virus spreads faster than its two ancestors, the SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), but has lower fatality. In this article, we aimed to summarize the transmission, symptoms, pathogenesis, diagnosis, treatment, and vaccine to control the spread of this fatal disease.

Coronavirus: Towards controlling of the pandemic - Indian scenario

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 462-468
Author(s):  
Latika kothari ◽  
Sanskruti Wadatkar ◽  
Roshni Taori ◽  
Pavan Bajaj ◽  
Diksha Agrawal
Keyword(s):  
Control Measures ◽  
The Novel ◽  
Medical Treatments ◽  
Health Crisis ◽  
The Public ◽  
Infection Control Measures ◽  
The Social ◽  
Asking Questions ◽  
The Government ◽  
Novel Coronavirus

Coronavirus disease 2019 (COVID-19) is a communicable infection caused by the novel coronavirus resulting in severe acute respiratory syndrome coronavirus 2 (SARS-CoV). It was recognized to be a health crisis for the general population of international concern on 30th January 2020 and conceded as a pandemic on 11th March 2020. India is taking various measures to fight this invisible enemy by adopting different strategies and policies. To stop the COVID-19 from spreading, the Home Affairs Ministry and the health ministry, of India, has issued the nCoV 19 guidelines on travel. Screening for COVID-19 by asking questions about any symptoms, recent travel history, and exposure. India has been trying to get testing kits available. The government of India has enforced various laws like the social distancing, Janata curfew, strict lockdowns, screening door to door to control the spread of novel coronavirus. In this pandemic, innovative medical treatments are being explored, and a proper vaccine is being hunted to deal with the situation. Infection control measures are necessary to prevent the virus from further spreading and to help control the current situation. Thus, this review illustrates and explains the criteria provided by the government of India to the awareness of the public to prevent the spread of COVID-19.

Association and treatment of diabetes in patients affected by Covid-19

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 1198-1201
Author(s):  
Syed Yasir Afaque
Keyword(s):  
Diabetes Mellitus ◽  
Prognostic Value ◽  
Heart Diseases ◽  
The Novel ◽  
The World ◽  
Treatment Of Diabetes ◽  
Coronavirus Infection ◽  
Composite Outcomes ◽  
Novel Coronavirus ◽  
The Impact

In December 2019, a unique coronavirus infection, SARS-CoV-2, was first identified in the province of Wuhan in China. Since then, it spread rapidly all over the world and has been responsible for a large number of morbidity and mortality among humans. According to a latest study, Diabetes mellitus, heart diseases, Hypertension etc. are being considered important risk factors for the development of this infection and is also associated with unfavorable outcomes in these patients. There is little evidence concerning the trail back of these patients possibly because of a small number of participants and people who experienced primary composite outcomes (such as admission in the ICU, usage of machine-driven ventilation or even fatality of these patients). Until now, there are no academic findings that have proven independent prognostic value of diabetes on death in the novel Coronavirus patients. However, there are several conjectures linking Diabetes with the impact as well as progression of COVID-19 in these patients. The aim of this review is to acknowledge about the association amongst Diabetes and the novel Coronavirus and the result of the infection in such patients.

The role and relationship of mindreading and social attunement in HRI – position statements of interdisciplinary researchers. Workshop HRI'20

2020 ◽  
Author(s):  
Agnieszka Wykowska ◽  
Jairo Pérez-Osorio ◽  
Stefan Kopp
Keyword(s):  
Mental States ◽  
Human Robot Interaction ◽  
Human Interaction ◽  
Artificial Agents ◽  
The Novel ◽  
Robot Interaction ◽  
Novel Coronavirus ◽  
Relationship Of ◽  
The Relationship

This booklet is a collection of the position statements accepted for the HRI’20 conference workshop “Social Cognition for HRI: Exploring the relationship between mindreading and social attunement in human-robot interaction” (Wykowska, Perez-Osorio & Kopp, 2020). Unfortunately, due to the rapid unfolding of the novel coronavirus at the beginning of the present year, the conference and consequently our workshop, were canceled. On the light of these events, we decided to put together the positions statements accepted for the workshop. The contributions collected in these pages highlight the role of attribution of mental states to artificial agents in human-robot interaction, and precisely the quality and presence of social attunement mechanisms that are known to make human interaction smooth, efficient, and robust. These papers also accentuate the importance of the multidisciplinary approach to advance the understanding of the factors and the consequences of social interactions with artificial agents.

The Political Impact of Affective Polarization: How Partisan Animus Shapes COVID-19 Attitudes

2020 ◽  
Author(s):  
James Druckman ◽  
Samara Klar ◽  
Yanna Krupnikov ◽  
Matthew Levendusky ◽  
John B. Ryan
Keyword(s):  
21St Century ◽  
American Politics ◽  
The Other ◽  
Policy Discourse ◽  
The Political ◽  
The Novel ◽  
Political Impact ◽  
Novel Coronavirus ◽  
Citizens Attitudes

Affective polarization is a defining feature of 21st century American politics—partisans harbor considerable dislike and distrust of those from the other party. Does this animus have consequences for citizens’ opinions? Such effects would highlight not only the consequences of polarization, but also shed new light onto how citizens form preferences more generally. Normally, this question is intractable, but the outbreak of the novel coronavirus allows us to answer it. We find that affective polarization powerfully shapes citizens’ attitudes about the pandemic, as well as the actions they have taken in response to it. However, these effects are conditional on the local severity of the outbreak, as the effects decline in areas with high caseloads—threat vitiates partisan reasoning. Our results clarify that closing the divide on important issues requires not just policy discourse but also attempts to reduce inter-partisan hostility.

Curve Estimation Modeling for Predictions of the Novel Coronavirus (Covid-19) Epidemic in Nigeria

2020 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Christian Ebere Enyoh ◽  
Andrew Wirnkor Verla ◽  
Chidi Edbert Duru ◽  
Emmanuel Chinedu Enyoh ◽  
Budi Setiawan
Keyword(s):  
State Governments ◽  
The Novel ◽  
Curve Estimation ◽  
Exponential Models ◽  
Inverse Models ◽  
Forward Prediction ◽  
S Curve ◽  
Novel Coronavirus ◽  
Best Fit ◽  
Official Data

Based on the official Nigeria Centre for Disease Control (NCDC) data, the current research paper modeled the confirmed cases of the novel coronavirus disease 2019 (COVID-19) in Nigeria. Ten different curve regression models including linear, logarithmic, inverse, quadratic, cubic, compound, power, S-curve, growth, and exponential were used to fit the obtained official data. The cubic (R2 = 0.999) model gave the best fit for the entire country. However, the growth and exponential had the lowest standard error of estimate (0.958) and thus may best be used. The equations for these models were e0.78897+0.0944x and 2.2011e0.0944x respectively. In terms of confirmed cases in individual State, quadratic, cubic, compound, growth, power and exponential models generally best describe the official data for many states except for the state of Kogi which is best fitted with S-curve and inverse models.  The error between the model and the official data curve is quite small especially for compound, power, growth and exponential models. The computed models will help to realized forward prediction and backward inference of the epidemic situation in Nigeria, and the relevant analysis help Federal and State governments to make vital decisions on how to manage the lockdown in the country.

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