scholarly journals Commonly available but highly effective protection against SARS-CoV-2 during gastrointestinal endoscopies

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254979
Author(s):  
Radan Keil ◽  
Štěpán Hlava ◽  
Petr Stanovský ◽  
Vladimír Ždímal ◽  
Jan Šťovíček ◽  
...  
Keyword(s):  
Health Problem ◽  
Initial Velocity ◽  
Effective Protection ◽  
Endoscopic Procedures ◽  
Protective Cover ◽  
Fluid Particles ◽  
Pass Through ◽  
Control Body ◽  
Made In ◽  
Number Of Particles

Background and aims SARS-CoV-2 is a worldwide serious health problem. The aim of this study was to demonstrate the number of potentially infectious particles present during endoscopic procedures and find effective tools to eliminate the risks of SARS-CoV-2 infection while performing them. Methods An experimental model which focused on aerosol problematics was made in a specialized laboratory. This model simulated conditions present during endoscopic procedures and monitored the formation of potentially infectious fluid particles from the patient’s body, which pass through the endoscope and are then released into the environment. For this reason, we designed and tested a prototype of a protective cover for the endoscope’s control body to prevent the release and spread of these fluid particles from its working channel. We performed measurements with and without the protective cover of the endoscope’s control body. Results It was found that liquid coming through the working channel of the endoscope with forceps or other instruments inside generates droplets with a diameter in the range of 0.1–1.1 mm and an initial velocity of up to 0.9 m/s. The average number of particles per measurement per whole measured area without a protective cover on the endoscope control body was 51.1; with this protective cover on, the measurement was 0.0, p<0.0001. Conclusions Our measurements proved that fluid particles are released from the working channel of an endoscope when forceps are inserted. A special protective cover for the endoscope control body, made out of breathable material (surgical cap) and designed by our team, was found to eliminate this release of potentially infectious fluid particles.

South Asian Developmental Crisis (Review Article)

1973 ◽  
Vol 12 (2) ◽  
pp. 181-188
Author(s):  
Rafiq Ahmad
Keyword(s):  
Second World War ◽  
World War ◽  
The Past ◽  
The Great Depression ◽  
Political Independence ◽  
Integrated Theory ◽  
Pass Through ◽  
Developed World ◽  
Second World ◽  
Made In

Like nations and civilizations, sciences also pass through period of crises when established theories are overthrown by the unpredictable behaviour of events. Economics is passing through such a crisis. The challenge thrown by the Great Depression of early 1930s took a decade before Keynes re-established the supremacy of economics. But this supremacy has again been upset by the crisis of poverty in the vast under-developed world which attained political independence after the Second World War. Poverty had always existed but never before had it been of such concern to economists as during the past twenty five years or so. Economic literature dealing with this problem has piled up but so have the agonies of poverty. No plausible and well-integrated theory of economic development or under-development has emerged so far, though brilliant advances have been made in isolated directions.

scholarly journals Changes in the charge of an α-Particle passing through matter

1923 ◽  
Vol 102 (717) ◽  
pp. 496-506 ◽  
Keyword(s):  
Initial Velocity ◽  
Rapid Decrease ◽  
Number Of Particles

It is remarkable that investigations on the velocity of α -particles have hitherto failed to detect with certainty particles of velocity less than about 8 x 10 8 cm. per second (0.4V 0 , where V 0 is the initial velocity of α -particles from RaC). Geiger believed he had found a-particles with velocities as low as 0.3V 0 . However, later work of Marsden and Taylor showed that when the velocity of an α -ray beam had fallen to about 0.45V 0 , any further increase of absorption caused a rapid decrease in the number of particles; the number fell to zero when the velocity had decreased to about 0.4V 0 . Thus the minimum observed energy was that which would be acquired by the α -particle in falling through about 600,000 volts. It is surprising that particles with such enormous energy should vanish, leaving no trace. Positive rays of much less energy have of course been detected in several ways.

scholarly journals Ciclos políticos hegemónicos: implicaciones para la gobernanza internacional

2018 ◽  
Vol 7 (3) ◽  
pp. 452-493
Author(s):  
Daniel Morales Ruvalcaba
Keyword(s):  
International Relations ◽  
International Governance ◽  
Political Cycles ◽  
National Power ◽  
Pass Through ◽  
Ideological Transition ◽  
Five Phases ◽  
Power Needs ◽  
International Behavior ◽  
Made In

El hegemón es un actor fundamental en la gobernanza internacional. No obstante, mientras que el comercio, poder y guerra han sido temas ampliamente abordados desde los estudios sobre hegemonía en las Relaciones Internacionales, se ha avanzado poco en análisis de las ideas que orientan el comportamiento del hegemón. La hipótesis aquí planteada es que las hegemonías recorren a lo largo de su existencia cinco fases (emergencia, despliegue, apogeo, declive y extinción) y, durante cada una de ellas, el Estado hegemónico asume ideologías específicas que orientan su comportamiento internacional, lo cual se traduce en la promoción de ciertas políticas internacionales, así como de alianzas y organizaciones internacionales con vocaciones específicas. Sin embargo, en la medida que evoluciona su poder nacional y el hegemón transita de una fase a otra, éste tiende a cambiar ideológicamente, abandonando ideas previas y asumiendo otras nuevas. Si bien dicha transición ideológica es pragmática -en función de las necesidades de su poder nacional- este cambio resulta discordante y criticable por otros actores del sistema. Este documento se compone de dos grandes partes: en la primera se establecen las cinco fases de un ciclo hegemónico y, luego, se exponen las ideologías que orientan el comportamiento del Estado hegemónico en ellas; la segunda parte se orienta a comprobar empíricamente las transiciones ideológicas durante las hegemonías neerlandesa, británica y estadounidense.   Abstract: The hegemon is a fundamental actor in international governance. However, while trade, power and war have been topics widely discussed from studies on hegemony in International Relations, little progress has been made in analyzing the ideas that guide the behavior of the hegemon. The hypothesis proposed here is that the hegemonies pass through five phases during their existence (emergence, deployment, apogee, decline and extinction) and, during each of them, the hegemonic State assumes specific ideologies that guide its international behavior. However, as the national power evolves, and the hegemon moves from one phase to another, it tends to change ideologically, abandoning previous ideas and assuming new ones. Although this ideological transition is pragmatic - depending on the power needs of the hegemon- this change results discordant and is criticized by other actors in the system. To demonstrate this, the following document is composed of two major parts: the first presents the five phases of a hegemonic cycle and, along with it, the ideologies that guide the behavior of the hegemonic State; the second part aims to empirically verify the ideological transitions during the hegemonies that have existed: the Dutch, the British and the American. Keywords: Hegemony, hegemonic political cycles, ideology, national power, hegemonic interregnum.     Recebido em: Agosto/2018. Aprovado em: Dezembro/2018.       

Pathogenetic mechanisms of anemic syndrome formation in patients with inflammatory bowel diseases

2021 ◽  
pp. 29-34
Author(s):  
Yu. P. Uspenskiy ◽  
Yu. A. Fominykh ◽  
K. N. Nadzhafova ◽  
O. I. Veduta
Keyword(s):  
Public Health ◽  
Ulcerative Colitis ◽  
Health Problem ◽  
Inflammatory Bowel Diseases ◽  
Public Health Problem ◽  
Significant Progress ◽  
Pathogenetic Mechanisms ◽  
Bowel Diseases ◽  
Inflammatory Bowel ◽  
Made In

Inflammatory bowel diseases are an urgent public health problem and are often complicated by the development of anemic syndrome. Significant progress has been made in the treatment of ulcerative colitis and Crohn's disease, but the correction of associated anemia in most cases remains insufficient. This article describes in detail the pathogenetic mechanisms of the formation of anemic syndrome in inflammatory bowel diseases, as well as possible ways to correct this condition.

scholarly journals CHILDREN FROM MIGRANTS’ FAMILIES IN RYAZAN’ AND KALUGA REGIONS: PROBLEMS OF INTEGRATION INTO RUSSIAN SOCIETY

2021 ◽  
pp. 142-157
Author(s):  
Elena A. Omelchenko
Keyword(s):  
Russian Federation ◽  
Psychological Adaptation ◽  
Migrant Children ◽  
Modern World ◽  
Russian Society ◽  
Interethnic Relations ◽  
Project Integration ◽  
The Russian Federation ◽  
Pass Through ◽  
Made In

The problems of adaptation and integration of ethnic migrants into the Russian society become more and more acute, due to the intensification of migration processes in the modern world and the involvement of the Russian Federation in them. Nearly 38 million children participate in the international migration, and many of them meet difficulties with the access to qualitative education, and have to pass through an enduring and tricky way of linguistic, cultural, social and psychological adaptation. The structure of conventional cultural and communicative, natural and geographical contacts, interactions of a child with his family and relatives is destroying, a child is stressed and experiences the crisis of identity, has to rethink and reinvent values and social regulations. The listed problems contribute to the increase of social disadaptation of ethnic migrants’ children; generate the situation of their potential failure in the future. Inside the society, accepting migrants, these problems complicate the structure of interethnic relations and links, and sometimes it becomes a ground for inter-ethnic tension. In the Russian Federation, the problem of adaptation of children from the families of ethnic migrants also becomes quite urgent, especially in the sphere of education. The author of the article has been researching this theme during the latest 20 years, and in 2019–2020 this research is made in the frames of the project “Integration of the children of ethnic migrants’ families via education: the methodical and consultative support of schools and kindergartens in the regions of the Russian Federation”, where 32 educational organizations in ten regions participate. The article illustrates a series of problems connected with the adaptation of migrant children, using the materials of the research made in the Ryazan’ and Kaluga regions. These children are mostly migrants of one-and-a-half or the second generation, and their families came to Russia from Kyrgyzstan, Uzbekistan, Azerbaijan and Tajikistan. Several paragraphs refer to the problems of adaptation to school of the Gypsy children. Basing on the results of the analysis, the author names main restrictions that prevent schools from the organization of intensive work aimed at linguistic, social and cultural adaptation of ethnic migrants’ children. She also defines main problems restraining the integration of the children from ethnic migrants’ families into the Russian educational environment and Russian society.

Il trattamento tradizionale dell'IPB nell'anziano: The traditional treatment of BPH in the elderly

1998 ◽  
Vol 65 (2) ◽  
pp. 222-225
Author(s):  
G. Fiaccavento ◽  
P. Scialpi ◽  
R. Zucconelli ◽  
P. Belmonte
Keyword(s):  
Life Expectancy ◽  
Elderly Patients ◽  
Retrospective Analysis ◽  
Open Surgery ◽  
Benign Prostatic Hypertrophy ◽  
The Elderly ◽  
Prostatic Hypertrophy ◽  
Traditional Treatment ◽  
Endoscopic Procedures ◽  
Made In

Longer life expectancy and the progress made in anaesthesiology have led to an increase over the last few years in the request for treatment of symptomatic benign prostatic hypertrophy (BPH) in elderly patients. A retrospective analysis on 270 patients aged 75 years who underwent surgery on the cervico-prostatic district between 1989 and 1997 showed a rate of complications (10% overall) comparable with that in patients of any age undergoing the same operation. This reinforces the conviction that both open surgery and endoscopic procedures for treating symptomatic BPH are safe and reliable even in the elderly.

Aggregation Studies: MR and MA With Poxvirus

1967 ◽  
Vol 25 ◽  
pp. 90-91
Author(s):  
D. G. Sharp ◽  
Kwang Soo Kim
Keyword(s):  
Cell Interaction ◽  
Actual State ◽  
New Host ◽  
Virus Particles ◽  
Particle Level ◽  
Dilute Suspension ◽  
The Individual ◽  
Quality Factor Q ◽  
Made In ◽  
Number Of Particles

The only instrument that gives direct information about virus-cell interaction at the individual particle level is the electron microscope. The counting of virus particles sedimented from dilute suspension for electron microscopy showed first that rather few of them produce plaques. Soon it was shown that the quality factor (Q=PFU/particles) was not a constant. It changed during the repeated passages required for adaptation of a virus to growth in a new host cell. More recently changes in Q have been observed when changes are made in the state of aggregation of the virus particles. These changes, their measurement and their meaning are the substance of this paper.Virus particles sedimented from dilute suspension fall upon a flat surface producing a pattern that shows coincidence pairs, triplets, etc., produced by chance falling together of separate particles. The number of these is small and it can be calculated. Aggregation in excess of this amount is true aggregation. It is the actual state of the virus particle population that encounters the cells of the monolayer on which plaques appear. From electron micrographs the frequency Ni of groups containing i particles is determined together with the total number of particles.

On the Particles in Fogs and Clouds

1893 ◽  
Vol 19 ◽  
pp. 260-263
Author(s):  
John Aitken
Keyword(s):  
Vapour Pressure ◽  
Dust Particles ◽  
Strong Wind ◽  
Great Care ◽  
Rapid Cooling ◽  
Particle Counter ◽  
Large Curvature ◽  
Small Water ◽  
Made In ◽  
Number Of Particles

At the beginning of the paper some observations made on the water particles in clouds on the Rigi on the 21st of May last are described. Previous observations with the fog-particle counter had shown that there is a relation between the density of a cloud and the number of water particles observed. On the occasion above referred to the number was very much greater than corresponded with the density. It is pointed out that the number of dust particles in the air which become centres of condensation depends on the rate at which the condensation is taking place, quick condensation causing a large number of particles to become active, slow condensation causing a small number; and that after the condensation has ceased a process of differentiation takes place, the larger particles, robbing the smaller ones of their water, owing to the vapour-pressure at the surface of drops of large curvature being less than at the surface of drops of smaller curvature. The particles in a cloud are by this process reduced in number, those remaining becoming larger and falling quicker, the cloud thus tending to become thinner by the reduction of the number of particles and by the falling of some of them. It is shown that the exceptional readings above referred to, obtained on the Rigi, were owing to the observations then made being taken in a new and rapidly-formed cloud, due to the strong wind blowing at the time causing a quick ascent and rapid cooling and condensation, the result being the formation of a large number of very small water particles. Though the number was very great, the particles were so small they were only just visible with great care with the magnifying power used in the instrument. Previous observations on cloud particles had been made in slowly-formed or in old clouds after the process of differentiation had been in play for some time, and after the drops had been reduced in number and increased in size.

scholarly journals XXI. On the compressibility of water

1820 ◽  
Vol 110 ◽  
pp. 324-329 ◽  
Keyword(s):  
Cast Iron ◽  
The Other ◽  
The Earth ◽  
Natural Pressure ◽  
Pass Through ◽  
Flexible Ring ◽  
Made In

Having believed for many years that water was an elas­tic fluid, I was induced to make some experiments to as­ certain the fact. This was done by constructing an instru­ment which I call a piezometer, and which is represented in Plate XXXII, Fig. 1. The cylinder, A, was three inches diameter, and eighteen inches long. The end, B, was made water tight by means of a plate which was soldered firmly to it. At the other end, C, a cap was made to screw on and off at pleasure; being also made water tight. The rod or plunger, D, which was five-sixteenths of an inch in diameter, was made to pass through a tight stuffing box, E. On the rod immedi­ately above the stuffing box, was fixed a flexible ring, a. A cannon, Fig. 2, of a sufficient size to contain the piezometer, was fixed vertically in the earth, the muzzle being left about eighteen inches above ground, and the touch-hole plugged tight. At the mouth a strong cap, A, was firmly screwed on. In the centre of this cap a small forcing pump, B, was tightly screwed, the piston of which was five-eighths of an inch in diameter. There was an aperture, C, in the cap, to introduce a valve for the purpose of ascertaining the degree of pressure. One pound pressure on this valve indicated an atmosphere. The piezometer was introduced into the cannon, and the water forced in until the cap showed signs of leakage; the valve at the same time indicating a pressure of one hundred atmospheres. The piezometer was then taken out of the cannon, and the flexible ring found to be eight inches up the rod, evidently proving the rod to have been forced into the cylinder that distance, showing also a compression of about one per cent. We have seen by re­peated experiments, that to be able to produce this degree of compression, three per cent must be pumped into the gun. This fact proves, either that the gun expands, or that the water enters the pores of the cast iron; it is probable both these circumstances contribute to produce this effect. This experiment was made in America in the year 1819, and before I had time to strengthen my apparatus for the purpose of making farther experiments, I was obliged to embark for this country. On my passage, however, I had frequent opportunities of repeating those I had already made, and of making others by a natural pressure. They were as follows. The piezometer, by the assistance of fifty-four pounds of lead attached to it, was sunk in the ocean to the depth of five hundred fathoms, which is about equal to the pressure of one hundred atmospheres. When drawn in, the gauge or ring was found removed eight inches up the rod, indi­cating, as in the before-mentioned experiment, a compression of one per cent. This experiment was several times repeated and with the same result.

THE FUNCTIONAL CAPACITY OF OVARIAN TISSUE TRANSPLANTED TO THE SPLEEN OR KIDNEY IN THE FERRET

1969 ◽  
Vol 45 (1) ◽  
pp. 91-97 ◽  
Author(s):  
B. T. DONOVAN
Keyword(s):  
Functional Capacity ◽  
Ovarian Tissue ◽  
Ovarian Hormones ◽  
Gonadal Hormones ◽  
Gonadal Steroids ◽  
Gonadotrophin Secretion ◽  
Uterine Growth ◽  
Pass Through ◽  
Made In

SUMMARY Ovarian tissue was autografted to the spleen or kidney of spayed anoestrous or oestrous ferrets to see whether inactivation of ovarian hormones occurred in the liver and to examine the feedback action of gonadal hormones on gonadotrophin secretion. Although the grafts survived in both sites as did homografts made in anoestrous females, the secretion of gonadal hormones was sufficient to cause oestrus only in a minority of animals and there was little difference in the function of grafts made to the spleen or kidney. Vulval swelling and uterine growth were caused by pellets of oestradiol inserted into the spleen so that it appears that this steroid can pass through the liver without loss of oestrogenic activity. It is concluded that little inactivation of gonadal steroids by the liver of the ferret takes place.

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