Nanocomposites: Retrospecr and Prospect

1992 ◽  
Vol 286 ◽  
Author(s):  
Rustum Roy
Keyword(s):  
Major Part ◽  
Size Range ◽  
Nanocomposite Materials ◽  
One Dimension ◽  
New Materials ◽  
Infinite Class ◽  
Materials Synthesis ◽  
The World ◽  
Two Phases ◽  
Nanometer Size Range

ABSTRACTIn this paper we make clear distinctions from the terms nanophase, nanocrystalline and deal only with nanocomposites defined as an interacting mixture of two phases, one of which is in the nanometer size range in at least one dimension. The author's origins of development of the idea that nanocomposites are a virtually infinite class of new materials are described.Then we refer to the results of our extensive studies of nanocomposites derived by solution-solgel techniques to illustrate the properties of such materials in the area of chemical and thermal reactivity.Finally it is pointed out that in the last few years nanocomposite materials have become a major part of new materials synthesis all over the world for applications ranging from mechanical to optical, to magnetic to dielectric.

scholarly journals Uncovering two phases of early intercontinental COVID-19 transmission dynamics

2020 ◽  
Vol 27 (8) ◽  
Author(s):  
Jing Yang ◽  
Juan Li ◽  
Shengjie Lai ◽  
Corrine W Ruktanonchai ◽  
Weijia Xing ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
International Travel ◽  
Contact Tracing ◽  
Genetic Sequencing ◽  
Response Strategies ◽  
The World ◽  
Containment Measures ◽  
The Usa ◽  
Community Transmission ◽  
Two Phases

Abstract Background The COVID-19 pandemic has posed an ongoing global crisis, but how the virus spread across the world remains poorly understood. This is of vital importance for informing current and future pandemic response strategies. Methods We performed two independent analyses, travel network-based epidemiological modelling and Bayesian phylogeographic inference, to investigate the intercontinental spread of COVID-19. Results Both approaches revealed two distinct phases of COVID-19 spread by the end of March 2020. In the first phase, COVID-19 largely circulated in China during mid-to-late January 2020 and was interrupted by containment measures in China. In the second and predominant phase extending from late February to mid-March, unrestricted movements between countries outside of China facilitated intercontinental spread, with Europe as a major source. Phylogenetic analyses also revealed that the dominant strains circulating in the USA were introduced from Europe. However, stringent restrictions on international travel across the world since late March have substantially reduced intercontinental transmission. Conclusions Our analyses highlight that heterogeneities in international travel have shaped the spatiotemporal characteristics of the pandemic. Unrestricted travel caused a large number of COVID-19 exportations from Europe to other continents between late February and mid-March, which facilitated the COVID-19 pandemic. Targeted restrictions on international travel from countries with widespread community transmission, together with improved capacity in testing, genetic sequencing and contact tracing, can inform timely strategies for mitigating and containing ongoing and future waves of COVID-19 pandemic.

scholarly journals Assessing a Linear Nanosystem's Limiting Reliability from its Components

2008 ◽  
Vol 45 (03) ◽  
pp. 879-887 ◽  
Author(s):  
Nader Ebrahimi
Keyword(s):  
Present State ◽  
Size Range ◽  
Two Dimensions ◽  
The Other ◽  
One Dimension ◽  
Present Moment ◽  
One Dimensional ◽  
The One ◽  
Fixed Moment ◽  
Nanosized Systems

Nanosystems are devices that are in the size range of a billionth of a meter (1 x 10-9) and therefore are built necessarily from individual atoms. The one-dimensional nanosystems or linear nanosystems cover all the nanosized systems which possess one dimension that exceeds the other two dimensions, i.e. extension over one dimension is predominant over the other two dimensions. Here only two of the dimensions have to be on the nanoscale (less than 100 nanometers). In this paper we consider the structural relationship between a linear nanosystem and its atoms acting as components of the nanosystem. Using such information, we then assess the nanosystem's limiting reliability which is, of course, probabilistic in nature. We consider the linear nanosystem at a fixed moment of time, say the present moment, and we assume that the present state of the linear nanosystem depends only on the present states of its atoms.

World Opinion and Colonial Status

1954 ◽  
Vol 8 (4) ◽  
pp. 468-483
Author(s):  
Kenneth Robinson
Keyword(s):  
British Empire ◽  
Major Part ◽  
Evolutionary Process ◽  
The World ◽  
Colonial Empire ◽  
World Opinion

“The great purpose of the British Empire is the gradual spread of freedom among all His Majesty's subjects in whatever part of the world they live. That spread of freedom is a slow evolutionary process. In some countries it is more rapid than others.… It may take generations or even centuries for the peoples in some parts of the Colonial Empire to achieve self-government. But it is a major part of our policy, even among the most backward peoples of Africa, to teach them and to encourage them always to be able to stand a little more on their own two feet.”

Foreign Private Investment in India 1920–1950

1978 ◽  
Vol 12 (4) ◽  
pp. 655-677 ◽  
Author(s):  
B. R. Tomlinson
Keyword(s):  
Foreign Investment ◽  
Economic History ◽  
Major Part ◽  
Private Investment ◽  
International Economy ◽  
The World ◽  
Foreign Private Investment ◽  
World Economic ◽  
Overseas Investment ◽  
Developed Nations

Overseas investment by developed nations in the less industrialized economies of Asia, Africa and Latin America is an important part of modern international economic history. Such investment has long been recognized as a potent force in integrating the international economy. It has also been placed at the heart of most theories of the expansion of European empires in the nineteenth century and it is seen as a major part of the ‘neo-colonialism’ that is widely thought to have characterized the world economic and political structure since 1945. This article will examine private foreign investment in India in the first half of the twentieth century, spanning the gap between the ‘imperial’ and the ‘neo-colonial’ epochs.

The Neuronal Crisis: Meditate to Comprehend the Nature of Psychosomatic Epidemic

2021 ◽  
Vol 64 (2) ◽  
pp. 110-127
Author(s):  
Henri Hude
Keyword(s):  
Major Part ◽  
The Body ◽  
Human Being ◽  
The West ◽  
The Unconscious ◽  
Experimental Knowledge ◽  
The World ◽  
The Absolute ◽  
Rational Consideration ◽  
Existential Problem

This articles describes the “neuronal crisis,” the epidemic of psychosomatic illnesses observed all over the world, particularly in the West. The paper looks into the deeper real causes and seeks the most effective kind of cure for this malady. This leads to rational consideration of the metaphysical dimension of the human being and the fundamental problems (those of evil, of freedom, of God, of the soul, and of the body), where lack of sufficiency plays a major part in the etiology of these pathologies, as the desire for the Absolute is the basis of the unconscious. This approach presumes the Freudian model but denies its purely libidinal interpretation that substitutes desire for the Absolute with libido. Hence, an explanatory system applied to increasingly serious pathologies: ailments, neuroses, depressions, and psychoses. Frustration of one’s desire for the Good gives rise to a sublimation of finite goodness. The inevitable desublimation, caused by anguish because of the Evil, intense guilt, and the dramatization of evils, causes neuroses as awkward but inevitable solutions to the existential problem that is still unresolved, due to lack of functional and experimental knowledge. Psychiatry and even medicine must take into account the metaphysical layer, and, therefore, operate within an existential dynamic, aiming to progress in wisdom and to discover man, man’s brain and body, as these are structured around the axis of his desire.

scholarly journals Communication Sentiment Analyzer using Machine Learning with Naive Bayes Bernoullinb

2019 ◽  
Vol 9 (1) ◽  
pp. 5976-5979
Keyword(s):  
Machine Learning ◽  
Social Media ◽  
Major Part ◽  
Naive Bayes ◽  
Naïve Bayes ◽  
User Preferences ◽  
Social Media Data ◽  
Machine Learning Model ◽  
The World ◽  
Media Data

In this never-ending social media era it is estimated that over 5 billion people use smartphones. Out of these, there are over 1.5 billion active users in the world. In which we all are a major part and before opening our messages we all are curious about what message we have received. No doubt, we all always hope for a good message to be received. So Sentiment analysis on social media data has been seen by many as an effective tool to monitor user preferences and inclination. Finally, we propose a scalable machine learning model to analyze the polarity of a communicative text using Naive Bayes’ Bernoulli classifier. This paper works on only two polarities that is whether the sentence is positive or negative. Bernoulli classifier is used in this paper because it is best suited for binary inputs which in turn enhances the accuracy of up to 97%.

Do We Really Know the Prevalence of MIH?

2016 ◽  
Vol 40 (4) ◽  
pp. 259-263 ◽  
Author(s):  
M Hernandez ◽  
JR Boj ◽  
E Espasa
Keyword(s):  
Diagnostic Criteria ◽  
Size Range ◽  
Age Groups ◽  
Cochrane Library ◽  
Correct Identification ◽  
Selection Methods ◽  
Online Databases ◽  
Molar Incisor Hypomineralization ◽  
The World ◽  
Age Range

Aim: To analyze the existing variability on molar incisor hypomineralization prevalence in the literature; to distinguish the various molar incisor hypomineralization prevalence rates in different countries, areas, and regions of the world; and to know the valid diagnostic criteria used for the correct identification of molar incisor hypomineralization prevalence. Study design: A literature review from Medline® and Cochrane Library® online databases was performed using five terms individually or in combination. Articles not reporting diagnostic criteria employed and articles not written English were excluded. The results were analyzed by country, region, year of study, sample size, range of age, and prevalence rate. Results: A total of 37 articles in English were selected from 1987 to 2014 and from those only 14 employed the EAPD's 2003 diagnostic criteria. The reported age range varied from 5.5 to 17 years; the most frequently range used was 7 to 9 years. A wide prevalence range from 2.8% to 44% was found and 82.61% of the articles reported calibrated examiners. Conclusions: Comparison among the results of the studies is difficult due to the use of different indexes and diagnostic criteria, the analysis variability, selection methods, and different age groups. In reality, we are probably far from knowing the real MIH prevalence.

A Cultural History of Objects in the Modern Age

2021 ◽  
Keyword(s):  
Cultural History ◽  
21St Century ◽  
Global Changes ◽  
New Materials ◽  
The West ◽  
Post Colonial ◽  
Everyday Objects ◽  
Modern Age ◽  
The World ◽  
History Of

A Cultural History of Objects in the Modern Age covers the period 1900 to today, a time marked by massive global changes in production, transportation, and information-sharing in a post-colonial world. New materials and inventions – from plastics to the digital to biotechnology – have created unprecedented scales of disruption, shifting and blurring the categories and meanings of the object. If the 20th Century demonstrated that humans can be treated like things whilst things can become ever more human, where will the 21st Century take us? The 6 volume set of the Cultural History of Objects examines how objects have been created, used, interpreted and set loose in the world over the last 2500 years. Over this time, the West has developed particular attitudes to the material world, at the centre of which is the idea of the object. The themes covered in each volume are objecthood; technology; economic objects; everyday objects; art; architecture; bodily objects; object worlds.

Coin Circulation in the Balkans in Late Antiquity

2007 ◽  
Author(s):  
P. GUEST
Keyword(s):  
Late Antiquity ◽  
Careful Analysis ◽  
Historical Narrative ◽  
The Balkans ◽  
Notable Feature ◽  
Starting Point ◽  
The World ◽  
Two Phases ◽  
Archaeological Excavations ◽  
Early Byzantine

The archaeological excavations carried out on late Roman and early Byzantine sites in the Balkans has revolutionized our knowledge of this part of the world in Late Antiquity. How these sites are dated is obviously important as, without accurate and reliable dating, it is difficult to understand how they fit into the wider historical narrative. This chapter takes the coins excavated at Dichin as its starting point and, by careful analysis, proposes a general dating scheme for the two phases of occupation at the settlement. The lack of coins struck during the years 474–518 is a notable feature of the assemblage from Dichin, a pattern that is repeated at most sites in the region where coins of the emperor Zeno are particularly rare. By looking at both site finds and hoards from the region, however, these explanations need to be revised as they are based on a numismatic mirage rather than archaeological fact.

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