scholarly journals One to only two: a short history of the centrosome and its duplication

2014 ◽  
Vol 369 (1650) ◽  
pp. 20130455 ◽  
Author(s):  
Greenfield Sluder
Keyword(s):  
Plant Cells ◽  
Spindle Assembly ◽  
Centrosome Duplication ◽  
Short History ◽  
Animal Cells ◽  
Higher Plant ◽  
Bipolar Spindle ◽  
Mother Centriole ◽  
History Of

This review discusses some of the history of the fundamental, but not fully solved problem of how the centrosome duplicates from one to only two as the cell prepares for mitosis. We start with some of the early descriptions of the centrosome and the remarkably prescient but then controversial inferences drawn concerning its function in the cell. For more than 100 years, one of the most difficult issues for the concept of the centrosome has been to integrate observations that centrosomes appear to be important for spindle assembly in animal cells yet are not evident in higher plant cells and some animal cells. This stirred debate over the existence of centrosomes and their importance. A parallel debate concerned the role of the centrioles in organizing centrosomes. The relatively recent elucidation of bipolar spindle assembly around chromatin allows a re-examination of the role of centrioles in controlling centrosome duplication in animal cells. The problem of how centrosomes precisely double in preparation for mitosis in animal cells has now moved to the mystery of how only one procentriole is assembled at each mother centriole.

Prosody in Automatic Speech Processing

2020 ◽  
pp. 632-645
Author(s):  
Anton Batliner ◽  
Bernd Möbius
Keyword(s):  
Speech Processing ◽  
High Performance ◽  
Early Years ◽  
Short History ◽  
Word Level ◽  
Dialogue Acts ◽  
Semantics And Pragmatics ◽  
Different Types ◽  
History Of

Automatic speech processing (ASP) is understood as covering word recognition, the processing of higher linguistic components (syntax, semantics, and pragmatics), and the processing of computational paralinguistics (CP), which deals with speaker states and traits. This chapter attempts to track the role of prosody in ASP from the word level up to CP. A short history of the field from 1980 to 2020 distinguishes the early years (until 2000)—when the prosodic contribution to the modelling of linguistic phenomena, such as accents, boundaries, syntax, semantics, and dialogue acts, was the focus—from the later years, when the focus shifted to paralinguistics; prosody ceased to be visible. Different types of predictor variables are addressed, among them high-performance power features as well as leverage features, which can also be employed in teaching and therapy.

scholarly journals Cell Cycle-Specific Disruption of the Preprophase Band of Microtubules in Fern Protonemata: Effects of Displacement of the Endoplasm by Centrifugation

1992 ◽  
Vol 101 (1) ◽  
pp. 93-98 ◽  
Author(s):  
TAKASHI MURATA ◽  
MASAMITSU WADA
Keyword(s):  
Cell Cycle ◽  
Cell Division ◽  
Plant Cells ◽  
Preprophase Band ◽  
Higher Plant ◽  
The Future ◽  
Prophase Nucleus ◽  
Original Region ◽  
Fern Protonemata

The preprophase band (PPB) of microtubules (MTs), which appears at the future site of cytokinesis prior to cell division in higher plant cells, disappears by metaphase. Recent studies have shown that displacement of the endoplasm from the PPB region by centrifugation delays the disappearance of the PPB. To study the role of the endoplasm in the cell cycle-specific disruption of the PPB, the filamentous protonemal cells of the fern Adiantum capilius-veneris L. were centrifuged twice so that the first centrifugation displaced the endoplasm from the site of the PPB and the second returned it to its original location. The endoplasm, including the nucleus of various stages of mitosis, could be returned by the second centrifugation to the original region of the PPB, which persists during mitosis in the centrifuged cells. When endoplasm with a prophase nucleus was returned to its original location, the PPB was not disrupted. When endoplasm with a prometa-phase telophase nucleus was similarly returned, the PPB was disrupted within 10 min of termination of centrifugation. In protonemal cells of Adiantum, a second PPB is often formed near the displaced nucleus after the first centrifugation. In cells in which the endoplasm was considered to have been returned to its original location at the prophase/prometaphase transition, the second PPB did not disappear even though the initial PPB was disrupted by the endoplasm. These results suggest that cell cycle-specific disruption of the PPB is regulated by some factor(s) in the endoplasm, which appears at prometaphase, i.e. the stage at which the PPB is disrupted in non-centrifuged cells.

Some Aspects of the Position of Aboriginal Women in Australian Society

1985 ◽  
Vol 13 (2) ◽  
pp. 32-60
Author(s):  
M.A. Vazey
Keyword(s):  
Turn Of The Century ◽  
Mutual Understanding ◽  
Short History ◽  
Australian Society ◽  
Post Colonial ◽  
Aboriginal Women ◽  
History Of ◽  
To Come

This paper includes a short history of Aboriginal women in Australia from about the turn of the century. This has been made possible by the writings of such women. Most non-Aboriginal women have been and are ignorant of this history. They need to understand this past in order to come to terms with it. Aboriginal women are also not aware of how misinformed non-Aboriginal women are of the role of Aboriginal women in their own society. An extensive dialogue is needed to develop the mutual understanding necessary for the construction of a peaceful and just post-colonial Australia.

scholarly journals Under Familiar Fire: Making Decisions during the “Kivu Crisis” 2008 in Goma, DR Congo

2010 ◽  
Vol 45 (2) ◽  
pp. 61-80 ◽  
Author(s):  
Silke Oldenburg
Keyword(s):  
Decision Making ◽  
Lived Experiences ◽  
Violent Conflict ◽  
State Of Exception ◽  
Short History ◽  
Dr Congo ◽  
The People ◽  
History Of ◽  
Decision Making Processes

This paper explores the decision-making processes used by the inhabitants of Goma during the Kivu Crisis in October 2008. The paper's aim is twofold: After providing a short history of the October 2008 events, it seeks in the empirical part to distinguish and clarify the role of rumours and narratives in the setting of violent conflict as well as to analyse their impact on decision-making processes. As the epistemological interest lies more on the people who stay rather than those who flee, in the second part the paper argues that the practice of routinization indicates a conscious tactic whose purpose is to counter the non-declared state of exception in Goma. Routinization is defined as a means of establishing order in everyday life by referring to narratives based on lived experiences.

scholarly journals Anastral meiotic spindle morphogenesis: role of the non-claret disjunctional kinesin-like protein.

1996 ◽  
Vol 134 (2) ◽  
pp. 455-464 ◽  
Author(s):  
H J Matthies ◽  
H B McDonald ◽  
L S Goldstein ◽  
W E Theurkauf
Keyword(s):  
Laser Scanning ◽  
Spindle Assembly ◽  
Time Lapse ◽  
Laser Scanning Confocal Microscopy ◽  
Meiotic Spindle ◽  
Bipolar Spindle ◽  
Scanning Confocal Microscopy ◽  
Spindle Poles ◽  
Assembly Kinetics

We have used time-lapse laser scanning confocal microscopy to directly examine microtubule reorganization during meiotic spindle assembly in living Drosophila oocytes. These studies indicate that the bipolarity of the meiosis I spindle is not the result of a duplication and separation of centrosomal microtubule organizing centers (MTOCs). Instead, microtubules first associate with a tight chromatin mass, and then bundle to form a bipolar spindle that lacks asters. Analysis of mutant oocytes indicates that the Non-Claret Disjunctional (NCD) kinesin-like protein is required for normal spindle assembly kinetics and stabilization of the spindle during metaphase arrest. Immunolocalization analyses demonstrate that NCD is associated with spindle microtubules, and that the centrosomal components gamma-tubulin, CP-190, and CP-60 are not concentrated at the meiotic spindle poles. Based on these observations, we propose that microtubule bundling by the NCD kinesin-like protein promotes assembly of a stable bipolar spindle in the absence of typical MTOCs.

scholarly journals Romanian documentary in transition : the role of documentary films in reshaping post-communist Romanian identity

2021 ◽  
Author(s):  
Petronela Serb
Keyword(s):  
Detailed Analysis ◽  
Electronic Media ◽  
Social Needs ◽  
Documentary Films ◽  
Short History ◽  
The Past ◽  
Bank Robbery ◽  
History Of

Since the fall of communism in 1989, Romanian citizens have changed dramatically, along with Romanian electronic media, which have transformed themselves from a one-party-controlled institution to a plethora of commercial broadcasters. By focusing on this era of dramatic transition, this thesis argues that documentary films have provided Romanians with the tools needed to deal with the past critically. More specifically, the intent of this thesis is to analyze how documentary films do the work of selecting, recollecting, and re-presenting narratives of the past, and to demonstrate that editorial choices resonate with wider social needs. The scope is limited to a short history of the documentary genre, focusing on a detailed analysis of two post-communist documentaries: Memorial of Pain ('Memorialul durerii', 1991), by TV producer Lucia Hossu-Longin and The Great Communist Bank Robbery ("Marele jaf comunist', 2004), by Alexandru Solomon. Ultimately, the thesis traces the ways in which trauma, shame, and amnesia also influence the shaping of both documentaries and identities.

scholarly journals Mentalizing Glasses: Multifocal Attention in Mentalization-Based Treatment and the Role of the Supervision

2021 ◽  
Vol 12 ◽  
Author(s):  
Pia Tohme ◽  
Martin Kolev
Keyword(s):  
Children And Adolescents ◽  
Crucial Role ◽  
Therapeutic Process ◽  
Short History ◽  
Therapeutic Setting ◽  
History Of

Bifocal attention has been conceptualized differently by various scholars; however, all converge in the idea that the therapeutic process includes the need for the therapist to focus his attention on more than one aspect of the therapeutic setting. We propose a novel view in the application of bifocal attention within the mentalizing framework (MBT) of working with children, adolescents, and their families. We start by providing a short history of the evolution of the construct of bifocal attention, followed by a brief description of the structure of MBT for children and adolescents, emphasizing the crucial role of bifocal and multiple attentions in the mentalizing therapist. We close by discussing the importance of continued supervision in facilitating the maintaining of mentalizing glasses in therapy.

Identification and preliminary characterization of a 65 kDa higher-plant microtubule-associated protein

1993 ◽  
Vol 105 (4) ◽  
pp. 891-901 ◽  
Author(s):  
J. Chang-Jie ◽  
S. Sonobe
Keyword(s):  
Polyclonal Antibodies ◽  
Cold Treatment ◽  
Plant Cells ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
High Concentration ◽  
Animal Cells ◽  
Higher Plant ◽  
Microtubule Protein

Microtubules in plant cells, as in animal cells, are dynamic structures. However, our lack of knowledge about the constituents of microtubules in plant cells has prevented us from understanding the mechanisms that control microtubule dynamics. To characterize some of these constituents, a cytoplasmic extract was prepared from evacuolated protoplasts (miniprotoplasts) of tobacco BY-2 cells, and microtubules were assembled in the presence of taxol and disassembled by cold treatment in the presence of Ca2+ and a high concentration of NaCl. SDS-PAGE analysis of triple-cycled microtubule protein revealed the presence of 120 kDa, 110 kDa and a group of 60–65 kDa polypeptides in addition to tubulin. Since these polypeptides had copolymerized with tubulin, through the three cycles of assembly and disassembly, and they bundle microtubules, we tentatively identified the three polypeptides as microtubule-associated proteins (MAPs). To characterize these factors further, triple-cycled microtubule protein was fractionated by Mono-Q anion-exchange chromatography and the microtubule-bundling activity of each fraction was examined. Fractions having microtubule-bundling activity contained only the 65 kDa MAP, an indication that the 65 kDa MAP is responsible for the bundling of microtubules. Purified 65 kDa MAP formed cross-bridge structures between adjacent microtubules in vitro. Polyclonal antibodies were raised in mice against the 65 kDa MAP. Immunofluorescence microscopy revealed that the 65 kDa MAP colocalized with microtubules in BY-2 cells throughout the cell cycle. Western blotting analysis of extracts from several species of plants suggested that the 65 kDa MAP and/or related peptides are widely distributed in the plant kingdom.

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