THEORETICAL ANALYSIS AND EXPERIMENT OF A NOVEL DEP CHIP WITH 3-D SILICON ELECTRODES

Author(s):  
LIMING YU ◽  
FRANCIS E. H. TAY ◽  
GUOLIN XU ◽  
CIPRIAN ILIESCU ◽  
MARIOARA AVRAM

This paper presents a novel dielectrophoresis (DEP) device where the DEP electrodes define the channel walls. This is achieved by fabricating microfluidic channel walls from highly doped silicon so that they can also function as DEP electrodes. Compared with planar electrodes, this device increases the exhibited dielectrophoretic force on the particle, therefore decreases the applied potential and reduces the heating of the solution. A DEP device with triangle electrodes has been designed and fabricated. Compared with the other two configurations, semi-circular and square, triangle electrode presents an increased force, which can decrease the applied voltage and reduce the Joule effect. Yeast cells have been used to for testing the performance of the device.

1989 ◽  
Vol 35 (12) ◽  
pp. 1081-1086 ◽  
Author(s):  
Byron F. Johnson ◽  
L. C. Sowden ◽  
Teena Walker ◽  
Bong Y. Yoo ◽  
Gode B. Calleja

The surfaces of flocculent and nonflocculent yeast cells have been examined by electron microscopy. Nonextractive preparative procedures for scanning electron microscopy allow comparison in which sharp or softened images of surface details (scars, etc.) are the criteria for relative abundance of flocculum material. Asexually flocculent budding-yeast cells cannot be distinguished from nonflocculent budding-yeast cells in scanning electron micrographs because the scar details of both are well resolved, being hard and sharp. On the other hand, flocculent fission-yeast cells are readily distinguished from nonflocculent cells because fission scars are mostly soft or obscured on flocculent cells, but sharp on nonflocculent cells. Sexually and asexually flocculent fission-yeast cells cannot be distinguished from one another as both are heavily clad in "mucilaginous" or "hairy" coverings. Examination of lightly extracted and heavily extracted flocculent fission-yeast cells by transmission electron microscopy provides micrographs consistent with the scanning electron micrographs.Key words: flocculation, budding yeast, fission yeast, scanning, transmission.


1994 ◽  
Vol 336 ◽  
Author(s):  
G. De Cesare ◽  
F. Irrera ◽  
F. Lemmi ◽  
F. Palma ◽  
M. Tucci

ABSTRACTWe present a novel family of photodetectors based on hydrogenated amorphous Si/SiC p-i-n-i-p heterostructures. Front p-i-n and rear n-i-p diodes work one as a detector and the other as a load impedance, depending on the polarity of the applied voltage. Due to different absorption at different wavelengths, the devices operate as bias-controlled light detectors in either the blue or the red regions. The energy gap and the thickness of the two intrinsic layers have been optimized to obtain a sharp wavelength selection (centered at 430 and 630 nm) with high rejection-ratios and good quantum efficiencies. The I-V characteristics and the device time response are investigated and simulated by SPICE.


2006 ◽  
Author(s):  
Ivan R. Perch-Nielsen ◽  
Peter John Rodrigo ◽  
Jesper Glückstad

1935 ◽  
Vol 8 (2) ◽  
pp. 151-173 ◽  
Author(s):  
W. B. Wiegand ◽  
J. W. Snyder

Abstract General Description.—The rubber pendulum is one of two devices (Wiegand, Trans. Inst. Rubber Ind., 1, 141 (1925)) which, by employing the Joule effect, constitute rubber heat engines in that they continuously convert heat into mechanical work. In Fig. 1 is shown the original pendulum. It consists of an ordinary pendulum of slow period fitted with a rubber band, one end of which is attached to the bob; the other to the upright support. This rubber band is stretched to four or five times its original length. Behind the upright is a metal shield so arranged that when the bob has reached the extremity of its swing the rubber band is clear of the shield, during the rest of the oscillation being in its shadow. Behind the pendulum and shield is an electric heating element with a copper reflector. The pendulum is started by displacement from the center towards one or other extremity. As this is done the rubber band is increased in length. At the extremity of the oscillation the stretch band is exposed to the radiant heat from the element, the Joule effect is brought into play and the band tends to shrink, thus pulling back the bob. Directly the band moves back within the shadow of the shield it cools, relaxes, and so allows the bob to swing out to the other side. Thereupon the band is once more heated up, contracts and so repeats the oscillation, which continues as long as the heat energy is supplied. When the electric current is turned off the pendulum dies down.


2012 ◽  
Vol 45 (2) ◽  
pp. 267-289 ◽  
Author(s):  
Yifat Bitton

The decision in Noar Kahalacha, an anti-segregation in education case that was recently delivered by the Israeli High Court of Justice, has been ‘naturally’ celebrated as the ‘Israeli Brown’. But is it? This article points to the differences between the monumental US Supreme Court decision of Brown and the Israeli Brown-equivalent – Noar Kahalacha. It contends that the two cases bear differences that stem from the divergent patterns of discrimination they represent, and that they reflect these differences squarely. The discrimination patterns reflected by the cases differ by virtue of traits that are traditionally overlooked in antidiscrimination theoretical analysis. Comparing the two cases, therefore, allows us an opportunity to revisit the notion of discrimination and its antidote, antidiscrimination. Drawing on the dichotomous concepts of de jure/de facto discrimination and difference/sameness discrimination, the article shows how these dual theoretical notions are determinative in shaping the distinctiveness of each of these cases. While the African American victims in Brown were easily recognised as a distinctive group suffering from de jure discrimination, the Mizrahi victims in Noar Kahalacha – who suffer from de facto discrimination within a Jewish hegemonic society – lacked such clear recognition. Accordingly, the discrimination narrative that Noar Kahalacha provides is very incomplete and carries only limited potential for effective application in future struggles to eliminate discriminatory practices against Mizrahis in Israel. Brown, on the other hand, carries a converse trait. Though criticised, Brown, nevertheless, strongly signifies the recognition by White America of its overarching discriminatory practices, and implies a genuine dedication to break from it. This understanding further illuminates the limitations embedded in the possibility of ‘importing’ highly contextual antidiscrimination jurisprudence from abroad into our system's highly contextual reality of discrimination.


1981 ◽  
Vol 1 (6) ◽  
pp. 535-543
Author(s):  
G B Kiss ◽  
A A Amin ◽  
R E Pearlman

Plasmids containing the nontranscribed central and terminal, but not the coding, regions of the extrachromosomal ribosomal deoxyribonucleic acid (rDNA) of Tetrahymena thermophila are capable of autonomous replication in Saccharomyces cerevisiae. These plasmids transform S. cerevisiae at high frequency; transformants are unstable in the absence of selection, and plasmids identical to those used for transformation were isolated from the transformed yeast cells. One plasmid contains a 1.85-kilobase Tetrahymena DNA fragment which includes the origin of bidirectional replication of the extrachromosomal rDNA. The other region of Tetrahymena rDNA allowing autonomous replication of plasmids in S. cerevisiae is a 650-base pair, adenine plus thymine-rich segment from the rDNA terminus. Neither of these Tetrahymena fragments shares obvious sequence homology with the origin of replication of the S. cerevisiae 2-microns circle plasmid or with ars1, an S. cerevisiae chromosomal replicator.


2012 ◽  
pp. 95-113
Author(s):  
Rita Biancheri

Up to now, in the traditional biomedical paradigm the terms "sex" and "gender" have either been used synonymously and the insertion of gender among the determining elements of conditions of wellbeing/disease has been difficult, and obstructed by disciplinary rigidities that retarded the acceptance of an approach which had already been largely found to be valid in other areas of research. The effected simplification demonstrated its limitations in describing the theme of health; but if, on the one hand, there has been a growing awareness of a subject which can in no way be considered "neutral", on the other hand there continues to be insufficient attention, both in theoretical analysis and in empirical research, given to female differences. The article is intended to support that the sick individual is a person, with his/her genetic heritage, his/her own cultural acquisitions and personal history, and own surrounding life context; but these and similar factors have not traditionally been taken into consideration by official medicine and welfare systems, despite a hoped-for socio-health integration.


2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Oleksandr Malykhin ◽  
Nataliia Oleksandrivna Aristova ◽  
Liudmyla Kalinina ◽  
Tetyana Opaliuk

The present paper addresses the issue of determining the best international practices for developing soft skills among students of different specialties through carrying out a theoretical review. Basing on literature on present-day theory the authors make an attempt to explain soft skills dichotomies, summarize existing approaches to classifying soft skills, consolidate and document best international practices for soft skills development among potential employees of different specialties including bachelor students, master students, doctoral and postdoctoral students. The data obtained in the theoretical analysis reveal that the possible ambiguities in the interpretation of the concept of “soft skills” are caused, on the one hand, by the dichotomic perception of their nature by present-day researchers and educators and, on the other hand, by the absence of the common language which makes it difficult to provide a more unified definition most satisfactory to all concerned. The authors are convinced that soft skills have a cross-cutting nature and regard them as personal and interpersonal meta-qualities and meta-abilities that are vital to any potential employee who is going to make positive contributions not only to his/her professional development but to the development of a company he/she is going to work for. The results of the conducted theoretical review clearly indicate that the absence of the unified understanding of the concept of “soft skills” is reflected in the existence of different approaches to classifying soft skills, let alone, the selection of didactic tools for developing soft skills among potential employees.


F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 912
Author(s):  
Andreas Martin Lisewski

Background: Knowledge about the origin of SARS-CoV-2 is necessary for both a biological and epidemiological understanding of the COVID-19 pandemic. Evidence suggests that a proximal evolutionary ancestor of SARS-CoV-2 belongs to the bat coronavirus family. However, as further evidence for a direct zoonosis remains limited, alternative modes of SARS-CoV-2 biogenesis should be also considered.    Results: Here we show that the genomes from SARS-CoV-2 and from SARS-CoV-1 are differentially enriched with short chromosomal sequences from the yeast S. cerevisiae at focal positions that are known to be critical for virus replication, host cell invasion, and host immune response. Specifically, for SARS-CoV-2, we identify two sites: one at the start of the viral replicase domain, and the other at the end of the spike gene past its critical domain junction; for SARS-CoV-1, one at the start of the RNA dependent RNA polymerase gene, and the other at the start of the spike protein’s receptor binding domain. As yeast is not a natural host for this virus family, we propose a directed passage model for viral constructs, including virus replicase, in yeast cells based on co-transformation of virus DNA plasmids carrying yeast selectable genetic markers followed by intra-chromosomal homologous recombination through gene conversion. Highly differential sequence homology data across yeast chromosomes congruent with chromosomes harboring specific auxotrophic markers further support this passage model. Model and data together allow us to infer a hypothetical tripartite genome assembly scheme for the synthetic biogenesis of SARS-CoV-2 and SARS-CoV-1.   Conclusions: These results provide evidence that the genome sequences of SARS-CoV-1, SARS-CoV-2, but not that of RaTG13, BANAL-20-52 and all other closest SARS coronavirus family members identified, are carriers of distinct homology signals that might point to large-scale genomic editing during a passage of directed replication and chromosomal integration inside genetically modified yeast cells.


2020 ◽  
pp. 36-40
Author(s):  
M. V. Ternova

The article analyzed concept of the study of art by Robin George Collingwood (1889-1943), a well-known English neo-hegelian philosopher. His significant part of the theoretical heritage is connected with the explanation of the nature of art and with the consideration of its condition during the period of the changing Oscar Wilde era to the era of Rudyard Kipling. The circle of problem such as content and form, character, image, mimesis, reflection, emotion, art and "street man" identified. All of them in Collingwood's presentation and interpretation significantly expanded the space of research not only English, but also European art criticism. The concept of study of art is "built" on the basis of an active understanding of historical and cultural traditions accented. The concept of art criticism of R.G. Collingwood – a famous English philosopher of the XIX-XX centuries, on the one hand, has self-importance, and on the other, although based on the traditions of contemporary humanities, still expands art history analysis of aesthetics through aesthetics and psychology. Recognizing the exhaustion of the English model of romanticism, R.G. Collingwood tries to outline the prospects for the development of art in the logic of the movement "romanticism – realism – avant-garde", which leads to the actualization of the problem of "mimesis – reflection". At the same time, the theorist's attention is consciously concentrated around the concept of "subject", the understanding of which is radically changing at the turn of the XIX-XX centuries. Theoretical material in the presentation of R.G. Collingwood is based on the work of Shakespeare, Reynolds, Turner, Cezanne, whose experience allows us to focus on the problem of "artist and audience". It is emphasized that Collingwood's position is ahead of its time, stimulating scientific research in the European humanities. The existence of indicative tendencies, which are distinguished in the logic of European cultural creation of the historical period, is emphasized.


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