scholarly journals Lightning Initiation from Fast Negative Breakdown is Led by Positive Polarity Dominated Streamers

2021 ◽  
Author(s):  
Anjing Huang ◽  
Steven Cummer ◽  
Yunjiao Pu
Keyword(s):  
Positive Polarity ◽  
Lightning Initiation

Human Event-Related Potentials to Higher-Order Acoustic Spatial Changes

2002 ◽  
Vol 16 (2) ◽  
pp. 114-118 ◽  
Author(s):  
Timo Ruusuvirta ◽  
Heikki Hämäläinen
Keyword(s):  
Working Memory ◽  
Mismatch Negativity ◽  
Spatial Information ◽  
Free Field ◽  
Event Related Potentials ◽  
Negative Polarity ◽  
Positive Polarity ◽  
Spatial Changes ◽  
Related Potentials ◽  
Human Event

Abstract Human event-related potentials (ERPs) to a tone continuously alternating between its two spatial loci of origin (middle-standards, left-standards), to repetitions of left-standards (oddball-deviants), and to the tones originally representing these repetitions presented alone (alone-deviants) were recorded in free-field conditions. During the recordings (Fz, Cz, Pz, M1, and M2 referenced to nose), the subjects watched a silent movie. Oddball-deviants elicited a spatially diffuse two-peaked deflection of positive polarity. It differed from a deflection elicited by left-standards and commenced earlier than a prominent deflection of negative polarity (N1) elicited by alone-deviants. The results are discussed in the context of the mismatch negativity (MMN) and previous findings of dissociation between spatial and non-spatial information in auditory working memory.

Commands in Wolaitta

2017 ◽  
Author(s):  
Azeb Amha
Keyword(s):  
Sentence Type ◽  
Positive Polarity ◽  
Present Contribution ◽  
Grammatical Categories ◽  
The Subject ◽  
Leave Taking ◽  
And Gender ◽  
Syntactic Properties

This chapter examines expressions of commands (imperatives) in Wolaitta and the ways in which the imperative is distinguished from statements and questions. Although each sentence type is formally distinct, imperatives and questions share a number of morpho-syntactic properties. Similar to declarative and interrogative sentences, imperatives in Wolaitta involve verbal grammatical categories such as the distinction of person, number, and gender of the subject as well as negative and positive polarity. In contrast to previous studies, the present contribution establishes the function of a set of morphemes based on -árk and -érk to be the expression of plea or appeal to an addressee rather than politeness when issuing a command. Instead, politeness in commands is expressed by using plural (pro)nominal and verbal elements. The imperative in Wolaitta is a robust construction which is also used in formulaic speeches such as leave-taking as well as in blessing, curses, and advice.

scholarly journals A distinct negative leader propagation mode

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
O. Scholten ◽  
B. M. Hare ◽  
J. Dwyer ◽  
N. Liu ◽  
C. Sterpka ◽  
...  
Keyword(s):  
Radio Telescope ◽  
Electric Discharge ◽  
Radio Astronomy ◽  
Propagation Mode ◽  
Common Phenomenon ◽  
High Charge ◽  
Initial Stage ◽  
Lightning Initiation ◽  
The Common

AbstractThe common phenomenon of lightning still harbors many secrets such as what are the conditions for lightning initiation and what is driving the discharge to propagate over several tens of kilometers through the atmosphere forming conducting ionized channels called leaders. Since lightning is an electric discharge phenomenon, there are positively and negatively charged leaders. In this work we report on measurements made with the LOFAR radio telescope, an instrument primarily build for radio-astronomy observations. It is observed that a negative leader rather suddenly changes, for a few milliseconds, into a mode where it radiates 100 times more VHF power than typical negative leaders after which it spawns a large number of more typical negative leaders. This mode occurs during the initial stage, soon after initiation, of all lightning flashes we have mapped (about 25). For some flashes this mode occurs also well after initiation and we show one case where it is triggered twice, some 100 ms apart. We postulate that this is indicative of a small (order of 5 km$$^2$$ 2 ) high charge pocket. Lightning thus appears to be initiated exclusively in the vicinity of such a small but dense charge pocket.

The complexity of coagulopathy pathogenesis in COVID-19.

2020 ◽  
Author(s):  
Е.П. Харченко
Keyword(s):  
Antiviral Effect ◽  
Surface Proteins ◽  
Structural Proteins ◽  
Atypical Pneumonia ◽  
Positive Polarity ◽  
S Protein ◽  
Immune Systems ◽  
Hemostasis System ◽  
Relationship Of

Введение. Коронавирус SARS-CoV-2 является новым вирусом, обладающим способностью осуществлять трансмиссию воздушно-капельным путем, вызывая тяжелое течение атипичной пневмонии, нередко сочетающейся с коагулопатиями. Роль структурных белков коронавируса в их патогенезе неизвестна. Цель исследования: с помощью биоинформационного анализа выявить в структурных белках коронавируса SARS-CoV-2 последовательности, гомологичные белкам системы гемостаза, и рассмотреть возможные сценарии их участия в патогенезе коагулопатий при COVID-19, а также объяснить существование вирусостатического эффекта гепарина. Материалы и методы. Для компьютерного анализа были использованы доступные в Интернете базы данных первичных структур белков коронавирусов и их рецепторов, а также поверхностных белков других вирусов, белков системы гемостаза и иммунной системы. Сравнивали аминокислотный состав белков и распределение оснόвных аминокислот (аргинина и лизина) в их первичных последовательностях. С целью выявления пептидного (иммуноэпитопного) родства структурных белков коронавирусов с белками системы гемостаза человека был выполнен поиск гомологичных последовательностей в их белках. Результаты. В структурных белках коронавируса SARS-CoV-2 выявлено множество последовательностей, гомологичных белкам системы гемостаза и иммунной системы. В отличие от коронавирусов SARS-CoV и MERS-CoV, S1-субъединица S-белка коронавируса SARS-CoV-2 имеет положительную полярность. Заключение. Множество последовательностей в структурных белках коронавируса SARS-CoV-2, гомологичных белкам системы гемостаза, потенциально способны вы- зывать различные сценарии патогенеза коагулопатий. Положительная полярность S1-субъединицы S-белка коронавируса SARS-CoV-2 позволяет объяснить неспецифическое взаимодействие ее с гепарином и его вирусостатический (неантикоагулянтный) эффект. Background. The coronavirus SARS-CoV-2 is a new virus capable of human-human transmission and inducing a severe atypical pneumonia often associated with coagulopathy. A role of SARS-CoV-2 structural proteins in coagulopathy pathogenesis is unknown. Objectives: to use a bioinformation analysis to identify SARS-CoV-2 sequences in the structural proteins that are homologous to hemostasis system proteins, regard their possible participation in coagulopathy pathogenesis and explain the antiviral effect of heparin. Materials / Methods. For computer analysis, Internet databases were used of the primary structures of coronavirus proteins and their receptors, as well as surface proteins of other viruses, proteins of hemostasis and immune systems. The amino acid composition of proteins and the distribution of basic amino acids (arginine and lysine) in their primary sequences were compared. For detection of peptide (immunoepitopic) relationship of coronaviruses structural proteins with human hemostasis proteins, a search for homologous sequences in their proteins was performed. Results. Many sequences have been identified in structural proteins of SARS-CoV-2 coronavirus that are homologous to the proteins of hemostasis and immune systems. In contrast with SARS-CoV and MERS-CoV coronaviruses, the S1-subunit of SARS-CoV-2 coronavirus S-protein has a positive polarity. Conclusions. Many sequences in SARS-CoV-2 structural proteins that homologous to hemostasis system proteins are potentially responsible for coagulopathy pathogenesis. The positive polarity of the S1-subunit of SARS-CoV-2 S-protein explains its nonspecific interaction with heparin and its virostatic (non-anticoagulant) effect.

Evidence for positive polarity of the spin moment in hcp Sm determined from a magnetic Compton-scattering experiment

1997 ◽  
Vol 56 (10) ◽  
pp. R5744-R5746 ◽  
Author(s):  
Hiromichi Adachi ◽  
Hiromitsu Ino ◽  
Akihisa Koizumi ◽  
Nobuhiko Sakai ◽  
Yoshikazu Tanaka ◽  
...  
Keyword(s):  
Compton Scattering ◽  
Spin Moment ◽  
Positive Polarity ◽  
Scattering Experiment

Electrohydrodynamic gas flow in a positive polarity wire-plate electrostatic precipitator and the related dust particle collection efficiency

2006 ◽  
Vol 64 (3-4) ◽  
pp. 259-262 ◽  
Author(s):  
Janusz Podliński ◽  
Jarosław Dekowski ◽  
Jerzy Mizeraczyk ◽  
Drazena Brocilo ◽  
Jen-Shih Chang
Keyword(s):  
Dust Particle ◽  
Gas Flow ◽  
Electrostatic Precipitator ◽  
Collection Efficiency ◽  
Positive Polarity ◽  
Particle Collection
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