Sub-second heat inactivation of coronavirus

2020 ◽  
Author(s):  
Yuqian Jiang ◽  
Han Zhang ◽  
Jose A. Wippold ◽  
Jyotsana Gupta ◽  
Jing Dai ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Hepatitis Virus ◽  
Heat Exposure ◽  
Simple System ◽  
Heat Inactivation ◽  
Heat Sensitivity ◽  
Viral Pathogens ◽  
The Past ◽  
Short Period ◽  
Steel Tubing

ABSTRACTHeat treatment denatures viral proteins that comprise the virion, making virus incapable of infecting a host. Coronavirus (CoV) virions contain single-stranded RNA genomes with a lipid envelope and 4 proteins, 3 of which are associated with the lipid envelope and thus are thought to be easily denatured by heat or surfactant-type chemicals. Prior studies have shown that a temperature of as low as 75 °C and treatment duration of 15 min can effectively inactivate CoV. The applicability of a CoV heat inactivation method greatly depends on the length of time of a heat treatment and the temperature needed to inactivate the virus. With the goal of finding conditions where sub-second heat exposure of CoV can sufficiently inactivate CoV, we designed and developed a simple system that can measure sub-second heat inactivation of CoV. The system is composed of capillary stainless-steel tubing immersed in a temperature-controlled oil bath followed by an ice bath, through which virus solution can be flowed at various speeds. Flowing virus solution at different speeds, along with a real-time temperature monitoring system, allows the virus to be accurately exposed to a desired temperature for various durations of time. Using mouse hepatitis virus (MHV), a beta-coronavirus, as a model system, we identified that 85.2 °C for 0.48 s exposure is sufficient to obtain > 5 Log10 reduction in viral titer (starting titer: 5 × 107 PFU/mL), and that when exposed to 83.4 °C for 0.95 s, the virus was completely inactivated (zero titer, > 6 Log10 reduction).IMPORTANCEThree coronaviruses (CoVs) have now caused global outbreaks within the past 20 years, with the COVID19 pandemic caused by SARS-CoV-2 still ongoing. Methods that can rapidly inactivate viruses, especially CoVs, can play critical roles in ensuring public safety and safeguarding personal health. Heat treatment of viruses to inactive them can be an efficient and inexpensive method, with the potential to be incorporated into various human-occupied spaces. In this work, a simple system that can heat-treat viruses for extremely short period was developed and utilized to show that sub-second exposure of CoV to heat is sufficient to inactivate CoV. This opens up the possibility of developing instruments and methods of disinfecting CoV in diverse settings, including rapid liquid disinfection and airborne virus disinfection. The developed method can also be broadly utilized to assess heat sensitivity of viruses other viral pathogens of interest and develop sub-second rapid heat inactivation approaches.

The Origin of the Moon and its Relationship to the Origin of the Solar System

1962 ◽  
Vol 14 ◽  
pp. 133-148 ◽  
Author(s):  
Harold C. Urey
Keyword(s):  
Solar System ◽  
The Moon ◽  
The Past ◽  
The Earth ◽  
Short Period ◽  
Origin Of The Moon

During the last 10 years, the writer has presented evidence indicating that the Moon was captured by the Earth and that the large collisions with its surface occurred within a surprisingly short period of time. These observations have been a continuous preoccupation during the past years and some explanation that seemed physically possible and reasonably probable has been sought.

The Diagnosis of Viral Disease by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 270-273
Author(s):  
William B. McCombs ◽  
Cameron E. McCoy
Keyword(s):  
Electron Microscopy ◽  
Hospital Stay ◽  
Viral Infections ◽  
Medical Profession ◽  
Bacterial Pathogens ◽  
Viral Disease ◽  
Viral Pathogens ◽  
Academic Interest ◽  
The Past

Recent years have brought a reversal in the attitude of the medical profession toward the diagnosis of viral infections. Identification of bacterial pathogens was formerly thought to be faster than identification of viral pathogens. Viral identification was dismissed as being of academic interest or for confirming the presence of an epidemic, because the patient would recover or die before this could be accomplished. In the past 10 years, the goal of virologists has been to present the clinician with a viral identification in a matter of hours. This fast diagnosis has the potential for shortening the patient's hospital stay and preventing the administering of toxic and/or expensive antibiotics of no benefit to the patient.

scholarly journals An Insight into Saponins from Quinoa (Chenopodium quinoa Willd): A Review

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1059 ◽  
Author(s):  
Khadija El Hazzam ◽  
Jawhar Hafsa ◽  
Mansour Sobeh ◽  
Manal Mhada ◽  
Moha Taourirte ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Bitter Taste ◽  
Biological Activities ◽  
Chenopodium Quinoa ◽  
Toxic Effects ◽  
Mechanical Abrasion ◽  
Important Group ◽  
The Past ◽  
Wide Range ◽  
Insight Into

Saponins are an important group found in Chenopodium quinoa. They represent an obstacle for the use of quinoa as food for humans and animal feeds because of their bitter taste and toxic effects, which necessitates their elimination. Several saponins elimination methods have been examined to leach the saponins from the quinoa seeds; the wet technique remains the most used at both laboratory and industrial levels. Dry methods (heat treatment, extrusion, roasting, or mechanical abrasion) and genetic methods have also been evaluated. The extraction of quinoa saponins can be carried out by several methods; conventional technologies such as maceration and Soxhlet are the most utilized methods. However, recent research has focused on technologies to improve the efficiency of extraction. At least 40 saponin structures from quinoa have been isolated in the past 30 years, the derived molecular entities essentially being phytolaccagenic, oleanolic and serjanic acids, hederagenin, 3β,23,30 trihydroxy olean-12-en-28-oic acid, 3β-hydroxy-27-oxo-olean-12en-28-oic acid, and 3β,23,30 trihydroxy olean-12-en-28-oic acid. These metabolites exhibit a wide range of biological activities, such as molluscicidal, antifungal, anti-inflammatory, hemolytic, and cytotoxic properties.

RAPIDLY GROWING DYSEMBRYOPLASTIC NEUROEPITHELIAL TUMOR

Neurosurgery ◽  
2006 ◽  
Vol 59 (6) ◽  
pp. E1337-E1338 ◽  
Author(s):  
Oltea Sampetrean ◽  
Taketoshi Maehara ◽  
Nobutaka Arai ◽  
Tetsuo Nemoto
Keyword(s):  
Complex Form ◽  
Interesting Case ◽  
Labeling Index ◽  
Pathological Examination ◽  
Dysembryoplastic Neuroepithelial Tumor ◽  
Complex Partial Seizures ◽  
Ki 67 ◽  
The Past ◽  
Short Period ◽  
Postoperative Diagnosis

Abstract OBJECTIVE During the past 15 years, the concept of dysembryoplastic neuroepithelial tumors has continued to evolve. We present an interesting case of dysembryoplastic neuroepithelial tumor that showed rapid growth during a short period of time. CLINICAL PRESENTATION A 9-year-old boy had been experiencing intractable complex partial seizures since the age of 7 years. Magnetic resonance imaging scans demonstrated a well-demarcated 3.5-cm lesion with a 1.5-cm ring-enhanced core in the left temporal lobe. One month later, the lesion had rapidly grown to occupy three times more space than on the first evaluation, with the ring-enhanced core reaching approximately five times its initial volume. INTERVENTION A combined tumor removal and epileptogenic focus resection surgery was performed immediately. In the pathological examination, the presence of the specific glioneuronal element with a Ki-67 labeling index of lower than 1%, as well as the glial component with a Ki-67 labeling index of 8%, led to a postoperative diagnosis of dysembryoplastic neuroepithelial tumor, complex form. No adjuvant therapy was performed. Five years after surgery, there is no evidence of any recurrence and the boy continues to be seizure free without antiepileptic drugs. CONCLUSION The lesion did not behave as a stable benign entity as it is generally accepted, and is, therefore, presented as an argument in favor of an early and complete resection.

First Report of the Welding Research Committee. A Preliminary Research into the Effect of Heat Treatment of Welds

1933 ◽  
Vol 124 (1) ◽  
pp. 569-599
Author(s):  
L. W. Schuster
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
High Temperature ◽  
Future Research ◽  
Considerable Variability ◽  
Research Committee ◽  
High Class ◽  
The Past ◽  
Cutting Out ◽  
Preliminary Research

With such considerations as the releasing of internal stress, the effect on corrodibility, and the practicability of carrying out high-temperature treatments, the present research does not deal. The experiments concern solely the changes in toughness brought about by heat treatment, and they represent a trial set of tests in which a particular high-class electrode was used, the results being intended as a guide for future research. In the past there has been considerable variability in the results obtained from a normalizing treatment by different experimenters, and as this was considered to be partly due to a difference in manner of cutting out the samples and a difference in the method of carrying out the treatment, the present treatments were all kept under careful control. The upper and lower “runs” were tested separately so that the effect of heat treatment on the coarse metal of the upper run and the fine metal of the lower runs might be subdivided. Throughout, microscopic examinations were made so that the change in structure might be correlated as far as possible with the change in the shock value. The particular weld metal tested gave very consistent results and the change in Izod value was found largely to follow the change in grain size.

Defect Spectroscopy on Damp-Heat Treated ZnO/CdS/Cu(In,Ga)(S,Se)2/Mo Heterojunction Solar Cells

2003 ◽  
Vol 58 (12) ◽  
pp. 691-702 ◽  
Author(s):  
C. Deibel ◽  
V. Dyakonov ◽  
J. Parisi
Keyword(s):  
Heat Treatment ◽  
Activation Energy ◽  
Solar Cells ◽  
Deep Level ◽  
Heat Exposure ◽  
Continuous Distribution ◽  
Open Circuit ◽  
Defect States ◽  
Band Bending ◽  
Test Cells

The changes of defect characteristics induced by accelerated lifetime tests on solar cells of the heterostructure ZnO/CdS/Cu(In,Ga)(S,Se)2/Mo are investigated. Encapsulated modules were shown to be stable against water vapor and oxygen under outdoor conditions, whereas the fill factor and open-circuit voltage of non-encapsulated test cells are reduced after prolonged damp heat treatment in the laboratory, leading to a reduced energy conversion efficiency. We subjected non-encapsulated test cells to extended damp heat exposure at 85 ◦C ambient temperature and 85% relative humidity for various time periods (6 h, 24 h, 144 h, 294 h, and 438 h). In order to understand the origin of the pronounced changes of the cells, we applied temperature-dependent current-voltage and capacitance voltage measurements, admittance spectroscopy, and deep-level transient spectroscopy. We observed the presence of electronic defect states which show an increasing activation energy due to damp heat exposure. The corresponding attempt-to-escape frequency and activation energy of these defect states obey the Meyer-Neldel relation. We conclude that the response originates from an energetically continuous distribution of defect states in the vicinity of the CdS/chalcopyrite interface. The increase in activation energy indicates a reduced band bending at the Cu(In,Ga)(S,Se)2 surface.We also observed changes in the bulk defect spectra due to the damp-heat treatment. - PACS: 73.20.hb, 73.61.Le

scholarly journals AT VENDE TILBAGE TIL UKENDTE STEDER - POSTHUKOMMELSE OG STED HOS JACOB DAMMAS, JACOB KOFLER OG MAJA MAGDALENA SWIDERSKA

1970 ◽  
Vol 42 (117) ◽  
pp. 113-130
Author(s):  
Anna Estera Mrozewicz
Keyword(s):  
Second Generation ◽  
Cultural Trauma ◽  
Documentary Films ◽  
The Past ◽  
Personal Stories ◽  
Short Period ◽  
Personal Approach ◽  
Personal Trauma ◽  
Related Identity ◽  
Theoretical Reflection

RETURNING TO UNFAMILIAR PLACES. PLACE AND POSTMEMORY IN THE WORKS OF JACOB DAMMAS, JACOB KOFLER, AND MAJA MAGDALENA SWI-DERSKA | The emigration of three thousand Polish-Jewish citizens to Denmark as a result of the events in March 1968 in Poland has only recently attracted attention from filmmakers and writers in Denmark. Two documentary films and a novel, created within a relatively short period of time, deal with the topic: Jacob Kofler’s Statsløs (Stateless), 2004, Jacob Dammas’ Kredens (Dresser), 2007, and Maja Magdalena Swiderska’s The Border Breaking Bunch, 2008. The authors are all children of refugees and represent second generation in relation to the cultural trauma of exile. The article examines aesthetic approaches developed by the authors as they (re)tell personal stories, which are mediated through various strategies of postmemory (Hirsch 1997). Postmemory is distinguished from memory by a non-indexical relation to the past and a generational distance, and from history by a highly personal approach. However, it is not addressed here as a psychological category. On the contrary, I argue that postmemory can be viewed as both an analytical and a narrative and aesthetic tool. Questions of place and place-related identity are relevant and inseparable from the three authors’ creative reimaginings of the cultural and personal trauma. Thus, the article focuses on the concepts of place and postmemory, and their interdependencies in the analysed works. Close readings are combined with theoretical reflection, which allows the objects and theories to illuminate each other.

scholarly journals Using naturalistic incubation temperatures to demonstrate how variation in the timing and continuity of heat wave exposure influences phenotype

2020 ◽  
Vol 287 (1932) ◽  
pp. 20200992 ◽  
Author(s):  
Anthony T. Breitenbach ◽  
Amanda W. Carter ◽  
Ryan T. Paitz ◽  
Rachel M. Bowden
Keyword(s):  
Heat Wave ◽  
Time Course ◽  
Heat Waves ◽  
Heat Exposure ◽  
Effect Of Temperature ◽  
Similar Time ◽  
Expression Of Genes ◽  
Short Period ◽  
The Face ◽  
Temperature Exposure

Most organisms are exposed to bouts of warm temperatures during development, yet we know little about how variation in the timing and continuity of heat exposure influences biological processes. If heat waves increase in frequency and duration as predicted, it is necessary to understand how these bouts could affect thermally sensitive species, including reptiles with temperature-dependent sex determination (TSD). In a multi-year study using fluctuating temperatures, we exposed Trachemys scripta embryos to cooler, male-producing temperatures interspersed with warmer, female-producing temperatures (heat waves) that varied in either timing during development or continuity and then analysed resulting sex ratios. We also quantified the expression of genes involved in testis differentiation ( Dmrt1 ) and ovary differentiation ( Cyp19A1 ) to determine how heat wave continuity affects the expression of genes involved in sexual differentiation. Heat waves applied during the middle of development produced significantly more females compared to heat waves that occurred just 7 days before or after this window, and even short gaps in the continuity of a heat wave decreased the production of females. Continuous heat exposure resulted in increased Cyp19A1 expression while discontinuous heat exposure failed to increase expression in either gene over a similar time course. We report that even small differences in the timing and continuity of heat waves can result in drastically different phenotypic outcomes. This strong effect of temperature occurred despite the fact that embryos were exposed to the same number of warm days during a short period of time, which highlights the need to study temperature effects under more ecologically relevant conditions where temperatures may be elevated for only a few days at a time. In the face of a changing climate, the finding that subtle shifts in temperature exposure result in substantial effects on embryonic development becomes even more critical.

New challenges in viral hepatitis

Gut ◽  
2012 ◽  
Vol 61 (Suppl 1) ◽  
pp. i1-i5 ◽  
Author(s):  
David Thomas ◽  
Fabien Zoulim
Keyword(s):  
Viral Hepatitis ◽  
Hepatitis Virus ◽  
Virus Infections ◽  
The Past ◽  
Treatment And Prevention ◽  
Introductory Article ◽  
Key Issues ◽  
New Challenges ◽  
Reliable Methods ◽  
Remarkable Progress

Over the past few decades there has been remarkable progress in viral hepatitis. Beginning with discovery of the viral agents, we now have reliable methods to diagnose and monitor all hepatitis virus infections, as well significant advances in treatment and prevention. Nonetheless, important challenges remain. This supplement to Gut looks forward to the next generation of challenges in the field of viral hepatitis, and this introductory article highlights several key issues.

Using relationship management to legitimate the monarchy: An analysis of the reign of King Juan Carlos I of Spain

2017 ◽  
Vol 14 (27) ◽  
Author(s):  
César García
Keyword(s):  
Public Support ◽  
Relationship Management ◽  
Mutual Benefit ◽  
Good Relationship ◽  
The Public ◽  
The Past ◽  
Short Period ◽  
Basic Relationship ◽  
High Level ◽  
New Democracy

This article explores the management of relationships by King Juan Carlos I of Spain to legitimate the monarchy as an institution and build a new democracy after Franco’s death in 1975. The high level of public support during most of his reign shows there is a correlation between good relationship management and the loyalty of the subjects. Only when some basic relationship management principles of mutual benefit, such as trust and openness with his subjects, were violated the level of support of Juan Carlos I, and the monarchy as an institution started to decline. Nonetheless, the value of relationship management has proved durable since the new monarch, Felipe VI, was able to recover in a relatively short period of time the public support that Juan Carlos I enjoyed in the past. This fact indicates that even in the case of disruptive monarchies, such as Spain, the power of relationship management has shown effectiveness to legitimate the institution. However, at the same time it also points out that in a public opinion regime monarchies have to show exemplarity and that involves not only to create mutual benefit for the citizenship through good deeds, since Juan Carlos I always behaved professionally as a business and diplomatic representative, but that there is feeling of trust between the monarch and the subjects.

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