scholarly journals Microscope objectives

Photoniques ◽  
2021 ◽  
pp. 59-64
Author(s):  
Jordan Moser

Microscope objectives are key components of optical microscopes, but they also equip experimental set-ups to focus laser beams or to collect photons emitted from any physical events to analyze or to diagnose. There are properties to take into account about their specifications and their usage for selecting the right microscope objective. They are used in a wide range of applications, from life sciences to material sciences, in laboratories and in industries and each application requires a specific microscope objective.

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.


2020 ◽  
Author(s):  
Luis Anunciacao ◽  
janet squires ◽  
J. Landeira-Fernandez

One of the main activities in psychometrics is to analyze the internal structure of a test. Multivariate statistical methods, including Exploratory Factor analysis (EFA) and Principal Component Analysis (PCA) are frequently used to do this, but the growth of Network Analysis (NA) places this method as a promising candidate. The results obtained by these methods are of valuable interest, as they not only produce evidence to explore if the test is measuring its intended construct, but also to deal with the substantive theory that motivated the test development. However, these different statistical methods come up with different answers, providing the basis for different analytical and theoretical strategies when one needs to choose a solution. In this study, we took advantage of a large volume of published data (n = 22,331) obtained by the Ages and Stages Questionnaire Social-Emotional (ASQ:SE), and formed a subset of 500 children to present and discuss alternative psychometric solutions to its internal structure, and also to its subjacent theory. The analyses were based on a polychoric matrix, the number of factors to retain followed several well-known rules of thumb, and a wide range of exploratory methods was fitted to the data, including EFA, PCA, and NA. The statistical outcomes were divergent, varying from 1 to 6 domains, allowing a flexible interpretation of the results. We argue that the use of statistical methods in the absence of a well-grounded psychological theory has limited applications, despite its appeal. All data and codes are available at https://osf.io/z6gwv/.


2020 ◽  
Vol 1 (10(79)) ◽  
pp. 12-18
Author(s):  
G. Bubyreva

The existing legislation determines the education as "an integral and focused process of teaching and upbringing, which represents a socially important value and shall be implemented so as to meet the interests of the individual, the family, the society and the state". However, even in this part, the meaning of the notion ‘socially significant benefit is not specified and allows for a wide range of interpretation [2]. Yet the more inconcrete is the answer to the question – "who and how should determine the interests of the individual, the family and even the state?" The national doctrine of education in the Russian Federation, which determined the goals of teaching and upbringing, the ways to attain them by means of the state policy regulating the field of education, the target achievements of the development of the educational system for the period up to 2025, approved by the Decree of the Government of the Russian Federation of October 4, 2000 #751, was abrogated by the Decree of the Government of the Russian Federation of March 29, 2014 #245 [7]. The new doctrine has not been developed so far. The RAE Academician A.B. Khutorsky believes that the absence of the national doctrine of education presents a threat to national security and a violation of the right of citizens to quality education. Accordingly, the teacher has to solve the problem of achieving the harmony of interests of the individual, the family, the society and the government on their own, which, however, judging by the officially published results, is the task that exceeds the abilities of the participants of the educational process.  The particular concern about the results of the patriotic upbringing served as a basis for the legislative initiative of the RF President V. V. Putin, who introduced the project of an amendment to the Law of RF "About Education of the Russian Federation" to the State Duma in 2020, regarding the quality of patriotic upbringing [3]. Patriotism, considered by the President of RF V. V. Putin as the only possible idea to unite the nation is "THE FEELING OF LOVE OF THE MOTHERLAND" and the readiness for every sacrifice and heroic deed for the sake of the interests of your Motherland. However, the practicing educators experience shortfalls in efficient methodologies of patriotic upbringing, which should let them bring up citizens, loving their Motherland more than themselves. The article is dedicated to solution to this problem based on the Value-sense paradigm of upbringing educational dynasty of the Kurbatovs [15].


Author(s):  
Alison Brysk

In Chapter 7, we profile the global pattern of sexual violence. We will consider conflict rape and transitional justice response in Peru and Colombia, along with the plight of women displaced by conflict from Syria and Central America, and limited international policy response. State-sponsored sexual violence and popular resistance to reclaim public space will be chronicled in Egypt as well as Mexico. We will track intensifying public sexual assault amid social crisis in Turkey, South Africa, and India, which has been met by a wide range of public protest, legal reform, and policy change. For a contrasting experience of the privatization of sexual assault in developed democracies, we will trace campus, workplace, and military rape in the United States.


Author(s):  
Andrew Hadfield

Lying in Early Modern English Culture is a major study of ideas of truth and falsehood from the advent of the Reformation to the aftermath of the Gunpowder Plot. The period is characterized by panic and chaos when few had any idea how religious, cultural, and social life would develop after the traumatic division of Christendom. Many saw the need for a secular power to define the truth; others declared that their allegiances belonged elsewhere. Accordingly there was a constant battle between competing authorities for the right to declare what was the truth and so label opponents as liars. Issues of truth and lying were, therefore, a constant feature of everyday life, determining ideas of identity, politics, speech, sex, marriage, and social behaviour, as well as philosophy and religion. This book is a cultural history of truth and lying from the 1530s to the 1610s, showing how lying needs to be understood in practice and theory, concentrating on a series of particular events, which are read in terms of academic debates and more popular notions of lying. The book covers a wide range of material such as the trials of Anne Boleyn and Thomas More, the divorce of Frances Howard, and the murder of Anthony James by Annis and George Dell; works of literature such as Othello, The Faerie Queene, A Mirror for Magistrates, and The Unfortunate Traveller; works of popular culture such as the herring pamphlet of 1597; and major writings by Castiglione, Montaigne, Erasmus, Luther, and Tyndale.


Author(s):  
Magda Nikolaraizi ◽  
Charikleia Kanari ◽  
Marc Marschark

In recent years, museums of various kinds have broadened their mission and made systematic efforts to develop a dynamic role in learning by offering a wide range of less formal experiences for individuals with diverse characteristics, including individuals who are deaf or hard-of-hearing (DHH). Despite the worthwhile efforts, in the case of DHH individuals, museums frequently neglect to consider their unique communication, cognitive, cultural, and learning characteristics, thus limiting their access and opportunities for fully experiencing what museums have to offer. This chapter examines the potential for creating accessible museum environments and methods that reflect an understanding of the diverse communication, cognitive, cultural, and learning needs of DHH visitors, all of which enhance their access and participation in the museum activities. The role of the physical features of museum spaces for the access and behavior of DHH visitors is emphasized, together with attention to exhibition methods and the communication and cognitive challenges that need to be considered so DHH visitors can get the maximum benefit. The chapter emphasizes the right of individuals who are DHH to nonformal learning and analyzes how museums could become more accessible to DHH individuals by designing, from the beginning, participatory learning experiences that address their diverse needs.


Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 471
Author(s):  
Eleonora Tosi ◽  
Renata Marcia de Figueiredo ◽  
Jean-Marc Campagne

The crucial role played by compounds bearing amide functions, not only in biological processes but also in several fields of chemistry, life polymers and material sciences, has brought about many significant discoveries and innovative approaches for their chemical synthesis. Indeed, a plethora of strategies has been developed to reach such moieties. Amides within chiral molecules are often associated with biological activity especially in life sciences and medicinal chemistry. In most of these cases, their synthesis requires extensive rethinking methodologies. In the very last years (2019–2020), enantioselective C-H functionalization has appeared as a straightforward alternative to reach chiral amides. Therein, an overview on these transformations within this timeframe is going to be given.


2021 ◽  
Vol 11 (10) ◽  
pp. 4613
Author(s):  
Gabriela-Maria Baci ◽  
Alexandra-Antonia Cucu ◽  
Adela Ramona Moise ◽  
Daniel Severus Dezmirean

Since ancient times, honey has been considered one of the most illustrious and esteemed natural products. Honey plays two key roles; specifically, it is an appreciated nutritional product, and also exhibits a wide range of beneficial properties for human health as a therapeutic agent. Furthermore, it has been shown that honey has valuable effects on the biological and physiological features of mulberry silkworms (Bombyx mori). Bombyx mori exhibits importance not only for the economy, but it also serves as an important biotechnological bioreactor for the production of recombinant proteins that have a great impact in the medical field and beyond. It also represents an important model organism for life sciences. In view of the fact that silk fibroin serves as a natural biopolymer that displays high biocompatibility with human organisms and due to honey’s various and remarkable properties for human health, the two elements are currently used together in order to develop ideal biomaterials for a wide range of purposes. In this review, by discussing the applicability of honey on Bombyx mori and beyond, the importance of honey for life sciences and related fields is spotlighted.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 57
Author(s):  
Juan-Guillermo Muñoz ◽  
Fabiola Angulo ◽  
David Angulo-Garcia

The boost-flyback converter is a DC-DC step-up power converter with a wide range of technological applications. In this paper, we analyze the boost-flyback dynamics when controlled via a modified Zero-Average-Dynamics control technique, hereby named Zero-Average-Surface (ZAS). While using the ZAS strategy, it is possible to calculate the duty cycle at each PWM cycle that guarantees a desired stable period-1 solution, by forcing the system to evolve in such way that a function that is constructed with strategical combination of the states over the PWM period has a zero average. We show, by means of bifurcation diagrams, that the period-1 orbit coexists with a stable period-2 orbit with a saturated duty cycle. While using linear stability analysis, we demonstrate that the period-1 orbit is stable over a wide range of parameters and it loses stability at high gains and low loads via a period doubling bifurcation. Finally, we show that, under the right choice of parameters, the period-1 orbit controller with ZAS strategy satisfactorily rejects a wide range of disturbances.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Caroline O’Keeffe ◽  
Laura Rhian Pickard ◽  
Juan Cao ◽  
Giuliano Allegri ◽  
Ivana K. Partridge ◽  
...  

AbstractConventional carbon fibre laminates are known to be moderately electrically conductive in-plane, but have a poor through-thickness conductivity. This poses a problem for functionality aspects that are of increasing importance to industry, such as sensing, current collection, inductive/resistive heating, electromagnetic interference (EMI) shielding, etc. This restriction is of course more pronounced for non-conductive composite reinforcements such as glass, organic or natural fibres. Among various solutions to boost through-thickness electrical conductivity, tufting with hybrid micro-braided metal-carbon fibre yarns is one of the most promising. As a well-characterised method of through thickness reinforcement, tufting is easily implementable in a manufacturing environment. The hybridisation of materials in the braid promotes the resilience and integrity of yarns, while integrating metal wires opens up a wide range of multifunctional applications. Many configurations can be produced by varying braid patterns and the constituting yarns/wires. A predictive design tool is therefore necessary to select the right material configuration for the desired functional and structural performance. This paper suggests a fast and robust method for generating finite-element models of the braids, validates the prediction of micro-architecture and electrical conductivity, and demonstrates successful manufacturing of composites enhanced with braided tufts.


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