Results 41 to 50 of about 4,018,839 (226)
Tree-Ring Dating and Archaeology in the American Southwest
, 1976 The relationship between archaeology and tree-ring dating, or dendrochronology, is reviewed. Until the past decade, the applications of tree-ring dating to archaeological problems had not been thoroughly exploited.
Robinson, William J.
core +4 more sources
Semicommutative and Armendariz Matrix Rings
AxiomsIn this paper, we construct some interesting high-order upper triangular matrix rings, which have semicommutative and Armendariz properties. Also, the relatively maximality of these rings as subrings of certain matrix rings is considered.
Gang Yang
doaj +1 more source
Effects of molecule force on free vibration for a micro electromagnetic harmonic drive system
Mechanics & Industry, 2021 In this paper, a micro electromagnetic harmonic drive system is proposed. Considering Van der Waals force, dynamics equation of the flexible ring for the micro drive system is deduced and resolved.
Zhao Dan, Xu Lizhong, Fu Yuming
doaj +1 more source
Global Efforts to Reduce Paediatric Cancer Care Disparities in Radiotherapy: A Decade Change
Pediatric Blood &Cancer, EarlyView.ABSTRACT Background We present an update on the status, needs and challenges faced by paediatric imaging and radiotherapy (RT) programmes globally after a previous survey conducted by the International Atomic Energy Agency (IAEA) 10 years prior. Methods We developed and distributed a 121‐question survey to radiation oncologists, medical physicists and ...
Raymond B. Mailhot Vega +10 more
wiley +1 more source
ON NIL-SYMMETRIC RINGS AND MODULES SKEWED BY RING ENDOMORPHISM
Science Journal of University of ZakhoThe symmetric property plays an important role in non-commutative ring theory and module theory. In this paper, we study the symmetric property with one element of the ring and two nilpotent elements of skewed by ring endomorphism on rings ...
Ibrahim Mustafa, Chnar Abdulkareem Ahmed
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Long-Term Impacts of Defoliator Outbreaks on Larch Xylem Structure and Tree-Ring Biomass
Frontiers in Plant Science, 2020 Defoliator insects are a major disturbance agent in many forests worldwide. During outbreaks, they can strongly reduce photosynthetic carbon uptake and impact tree growth.
Daniele Castagneri +6 more
doaj +1 more source
INTRASTROMAL CORNEAL KERARING SEGMENTS FOR KERATOCONUS [PDF]
Zagazig University Medical Journal, 2014 AIM: To assess the outcome of intrastromal corneal ring segments (Kera ring) for keratoconus.Study design: Retrospective noncomparative interventional case series.Patients and Methods: Sixty keratoconus eyes of 48 patients that had intrastromal corneal ...
Aly Bayoumy +3 more
doaj +1 more source
Engineering Applications of Computational Fluid Mechanics, 2022 To analyze the complex spatiotemporal evolution law of the high-speed jet flow field in a liquid-ring pump ejector, both the classic and spectral proper orthogonal decomposition (SPOD) methods were introduced to decompose the transient flow field based ...
Li-Jie Jiang +3 more
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Pediatric Blood &Cancer, EarlyView.ABSTRACT Background Shwachman–Diamond syndrome (SDS) is a rare autosomal recessive ribosomopathy characterized by bone marrow failure and multisystem involvement, with emerging evidence of associated neurocognitive impairment. Methods We conducted a retrospective study of 240 individuals with biallelic Shwachman–Bodian–Diamond syndrome (SBDS) mutations
Jane Koo +11 more
wiley +1 more source
Rings Over Which Certain Modules Are YJ-Injective [PDF]
Kirkuk Journal of Science, 2009 In this paper we continue to study the concept of YJ-injectivity which was first introduced by Ming in 1985. Furthermore, we give some characterizations and properties for it.
Abdullah M. Abdul-Jabbar
doaj +1 more source