Results 101 to 110 of about 11,557,211 (324)

Statistical analysis of low-latitude spread F observed over Puer, China, during 2015–2016

Earth, Planets and Space, 2019
Statistical analysis of spread F (SF), recorded at Puer (PUR, 22.7° N, 101.05° E, Dip Latitude 12.9° N) during 2015–2016, was carried out to reveal its characteristics at the northern equatorial ionization anomaly.
Ting Lan, Chunhua Jiang, Guobin Yang, Yuannong Zhang, Jing Liu, Zhengyu Zhao   +5 more
doaj   +1 more source

Equatorial spread F and interplanetary magnetic field.

Journal of geomagnetism and geoelectricity, 1977
A reversal of the vertical F region drifts over the magnetic equator during the nighttime hours from the normal downward direction to upward direction is shown to cause the sudden generation of the Range type spread F configuration on the ionograms after a delay of about one hour.
openaire   +2 more sources

Observations of equatorial spread‐F from Haleakala, Hawaii

Geophysical Research Letters, 2002
Since the 1920s it has been known that the equatorial ionosphere can become highly disturbed in the post‐sunset period. We have placed a new array of instruments on top of the Haleakala Volcano in Hawaii to study these disturbances from midlatitudes. Two airglow imagers provide two‐dimensional snapshots of the development of these disturbances during ...
Michael C. Kelley, Jonathan J. Makela, Brent M. Ledvina, Paul M. Kintner   +3 more
openaire   +1 more source

VHF radio wave scattering due to range and frequency types of equatorial spread-F

, 1978
Comparing vertical incidence ionograms during spread-F conditions at the equatorial station Huancayo and modified range time interrsity records of 50 MHz scatter echoes at Jicamarca, it has been shown that the range type of spread-F is very efficient for
Rastogi, R.G., Woodman, R. F.
core   +1 more source

First reports on the relationship between the eggshell and bone mineralization in Rhinoclemmys punctularia punctularia embryos

The Anatomical Record, EarlyView.
Abstract Composed of various minerals, the eggshell provides ideal conditions for embryonic development, and understanding its composition and structure is essential for clarifying its relationship with bone formation. This study characterized the structure and mineral profile of the Rhinoclemmys punctularia punctularia eggshell in relation to ...
Igor Mathias Trindade Lemos, Deise Cardoso de Lima, Antônio Basílio Guerreiro Júnior, Brenda Stefany dos Santos Braga, Antônio Messias Costa, Ana Cássia Sarmento Ferreira, Maria Auxiliadora Ferreira, Verônica Oliveira‐Bahia, Diva Anelie de Araújo Guimarães   +8 more
wiley   +1 more source

Anatomy of plasma structures in an equatorial spread F event

Geophysical Research Letters, 2001
This paper investigates the small scale plasma structures observed by ROCSAT‐1 in the equatorial F region through the newly developed Hilbert‐Huang transform (HHT) method in the time (space) domain under the frozen‐in approximation. The new method allows us to decompose the non‐stationary, nonlinear data into a finite number of intrinsic scale modes ...
K. Y. Chen, H. C. Yeh, S. Y. Su, C. H. Liu, Norden E. Huang   +4 more
openaire   +1 more source

Association between equatorial and tropical spread-F

, 2003
83-92Comparative study of spread-F is made from the quarter-hourly ionograms at Huancayo, near the magnetic equator and Bogota, close to the anomaly crest region in the same longitude sector.
Alex, S, Chandra, H, Rastogi, R G
core  

Ionospheric coupling, especially between ionogram-recorded spread-F and sporadic-E enhancements at an equatorial-anomaly crest station, Chung-Li [PDF]

, 2002
[1] The analysis of ionograms recorded at Chung-Li, a station situated near the crest of the equatorial ionosphere anomaly, finds that there is coupling between the nighttime F and E layers at the onset of spread-F, as is the case in midlatitudes.
Bowman, G. G., Mortimer, I. K.
core   +1 more source

Redescription of †Eobrasilia coutoi (Metatheria: Polydolopimorphia), a unique sclerocarpophagous metatherian from the Palaeogene of South America: Systematic affinities, and paleoecological and evolutionary implications

The Anatomical Record, EarlyView.
Abstract The ‘Palaeogene strata’ of the Itaboraí Basin (upper Paleocene‐lower Eocene), Southeastern Brazil, has preserved 29 genera and almost 50 species of metatherians (about 65% of its mammalian diversity). Among them, Eobrasilia coutoi Simpson, 1947 is the most enigmatic due to its quite fragmentary nature.
Leonardo M. Carneiro, Hugo Bampi, Ana C. Bernardes‐Dias, Lidiane Asevedo, João P. P. Araújo, Matheus R. Arêas, Alessandra S. Machado, Ricardo T. Lopes, Rafael C. Silva, Marina B. Soares, Gustavo R. Oliveira   +10 more
wiley   +1 more source

Ocular morphology and morphometry of the great egret (Ardea alba): A comprehensive anatomical description

The Anatomical Record, EarlyView.
Abstract Ardea alba (Linnaeus, 1758) is widely distributed, yet knowledge of its ocular morphology remains limited. This study described the morphometry and morphology of the eyeball and its accessory glands in six specimens using radiography, morphometry, light and scanning electron microscopy, and 3D scanning.
Julia Vaz Feio, Max Alex Santos Ferreira, Iara Fernanda Lima do Espírito Santo, Elane Guerreiro Giese, Érika Branco, Antônio Basílio Guerreiro Junior, Ana Rita de Lima   +6 more
wiley   +1 more source