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Start Over Coverage 273-277

1. An example of a positive semidefinite double sequence which is not a moment sequence

Creator:
Bisgaard, Torben Maack
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
double sequence, positive definite, and moment sequence
Language:
English
Description:
The first explicit example of a positive semidefinite double sequence which is not a moment sequence was given by Friedrich. We present an example with a simpler definition and more moderate growth as $(m, n) \rightarrow \infty $.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Diel acid fluctuations in C4 amphibious grasses

Creator:
Keeley, J. E.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
aquatic and terrestrial leaves, 14C labelling, chlorophyll, malic acid, Neostapfia colusana, Orcuttia californica and O. viscida, titratable acidity, and Tuctoria greenie
Language:
Multiple languages
Description:
Orcuttieae is a small tribe of C4 grasses endemic to seasonal pools in the southwestern U.S., comprising the basal genus Neostapfia, Tuctoria, and the most derived group, Orcuttia. Growth is initiated underwater, and when pools dry, species undergo a metamorphosis replacing aquatic foliage with terrestrial foliage. O. californica and O. viscida exhibit CAM-like diel fluctuations in acidity in the aquatic foliage. Pulse-chase studies showed that although CO2 was fixed into malic acid in the dark, an overnight chase in the dark revealed that most label was not retained in organic acids, indicating a role other than CAM. Terrestrial foliage exhibited a very different diel fluctuation; acids accumulated during the day, and diminished overnight. Malic acid predominated and was secreted on the surface of the leaf in a manner similar to another arid land species. This terrestrial daytime acid accumulation may not be related to photosynthetic pathway but may play an anti-herbivore function. No acid fluctuations were observed in either N. colusana or T. greenei.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Rhaphidotrema kiatkiongi, a new genus and species of blood fluke (Digenea: Aporocotylidae) from Arothron hispidus (Osteichthyes: Tetraodontidae) from the Great Barrier Reef, Australia

Creator:
Yong, Russell Q. Y. and Cribb, Thomas H.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Aporocotylidae, Rhaphidotrema, Arothron hispidus, Tetraodontidae, new genus, and Great Barrier Reef
Language:
English
Description:
A new genus of fish blood flukes (Aporocotylidae Odhner, 1912) is proposed for a species found on reefs surrounding Lizard Island on the northern Great Barrier Reef. Rhaphidotrema kiatkiongi gen. et sp. n. was recovered from the heart of the stars-and-stripes pufferfish, Arothron hispidus (L.) (Tetraodontidae). Rhaphidotrema kiatkiongi is notable as the first digenean reported to possess a penis stylet. It also differs from all other aporocotylid flukes in having a combination of 18-19 testes in a group at the ends of the intestinal caeca, a broad lanceolate body shape with a dextrally-directed posterior bend at the level of the male genital pore, and separate genital pores, with the female genital pore distinctly sinistral and the male genital pore slightly dextral to midline. This is the second species of aporocotylid fluke reported from this pufferfish.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. RTS šum v tranzistorech MOSFET

Creator:
Pavelka, Jan, Šikula, Josef, Tacano, Munecazu, and Toita, Masato
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
RTS noise, 1/f noise, MOSFET, traps, RTS šum, 1/f šum, and pasti
Language:
Czech
Description:
Low-frequency noise in MOSFETs is given mainly by 1/f-like noise and RTS (random telegraph signal) noise components, generated by charge carriers capture and emission by traps near channel. In this paper experimental results on RTS noise amplitude and mean capture and emission times are analysed as a function of applied bias and temperature and traps characteristics, such as activation energy and their position in channel are estimated. and Nízkofrekvenční šum v tranzistorech MOSFET je dán především složkami se spektrem typu 1/f a šumem RTS (random telegraph signal), vznikajícím v důsledku zachycování a uvolňování nosičů náboje na pastech v blízkosti kanálu. Článek podává souhrn experimentálních výsledků o závislosti amplitudy RTS šumu a střední doby zachycení a emise na aplikovaném napětí a teplotě, na jejich základě lze pak stanovit některé charakteristiky pastí, jako aktivační energii nebo polohu v kanálu.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Vírový mikroskop pro super-rozlišovací lokalizační zobrazení a dynamické sledování fluorescenčně excitovaných a slabě rozptylujících dielektrických a kovových nanočástic

Creator:
Bouchal, Petr and Bouchal, Zdeněk
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
microscopes, mikroskopy, světelné víry, nedifrakční svazky, fluorescenční zobrazení, and sledování částic
Language:
Czech
Description:
The paper describes design and realization of a flexible vortex microscope allowing three-dimensional localization and tracking of fluorescence excited and weakly scattering nanoparticles. Information about localized objects is obtained from the interference of light vortices created by optical components, which modulate both amplitude and phase of light and were prepared by electronbeam lithography. Design of the vortex microscope is based on the inverted microscope Nikon Eclipse E600 operating with additional illumination and imaging modules that enable recording and reconstruction of the sample in fluorescence, episcopic and diascopic imaging modes. The variability of the vortex microscope allows a dynamic spatial localization of nanoparticles in the axial range exceeding 23 times the depth of field of the microscope objective used, achieving an isotropic accuracy of 10-50 nm. The tracking of nanoparticles under Brownian motion was demonstrated in a volume of 14×10×16 mm3 . The practical usability of the system was tested by fluorescence imaging of LW13K2 cells and localization of cellular proteins. and V článku je popsán návrh a realizace flexibilního vírového mikroskopu, který umožňuje trojrozměrnou lokalizaci a sledování fluorescenčně excitovaných a slabě rozptylujících částic nanometrových rozměrů. Informace o lokalizovaných objektech je získána z interference světelných vírů vytvořených optickými komponentami, které současně modulují amplitudu i fázi světla a byly připraveny technikou elektronové litografie. Základem experimentálního systému je mikroskop Nikon Eclipse E600 rozšířený o zobrazovací a osvětlovací moduly, které umožňují záznam a rekonstrukci vzorku ve fluorescenčním, episkopickém a diaskopickém zobrazovacím režimu. Variabilita konstrukce vírového mikroskopu umožňuje dynamickou prostorovou lokalizaci nanometrových objektů v axiálním rozsahu převyšujícím až 23krát hloubku ostrosti použitého objektivu při izotropní přesností 10-50 nm. Sledování nanočástic při Brownově pohybu bylo demonstrováno v objemu 14×10×16 mm3 . Praktická použitelnost systému byla testována při fluorescenčním zobrazení krysích buněk LW13K2 a lokalizaci buněčných proteinů.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public