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Lost and found: Geologists 'resurrect' missing tectonic plate(图)
Lost and found Geologists resurrect missing tectonic plate
2020/10/30
The existence of a tectonic plate named Resurrection has long been a topic of debate among geologists, with some arguing it was never real. Others say it subducted -- moved sideways and downward -- in...
In search of an undersea kelp forest's missing nitrogen(图)
undersea kelp forest missing nitrogen
2019/10/28
Plants need nutrients to grow. So scientists were surprised to learn that giant kelp maintains its impressive growth rates year-round, even in summer and early fall when ocean currents along the Calif...
Scientists find missing clue to how HIV hacks cells to propagate itself(图)
Scientists missing clue HIV hacks cells propagate itself
2017/11/24
Computer modeling has helped a team of scientists, including several scholars from the University of Chicago, to decode previously unknown details about the process by which HIV forces cells to spread...
Best (but oft-forgotten) practices: intention-to-treat, treatment adherence, and missing participant outcome data in the nutrition literature
clinical trials patient dropouts randomization adherence intention to treat missing outcome data per protocol
2018/12/18
Among clinical trials of adequate size, randomization balances both known and unknown prognostic factors between trial arms, thus allowing an unbiased comparison of intervention and control.
Photochemistry of a Bacterial Photosynthetic Reaction Center Missing the Initial Bacteriochlorophyll Electron Acceptor
Carbon nanotubes Composite Terahertz properties
2016/5/25
A novel chromophore composition of the bacterial photosynthetic reaction center (RC) has been discovered: RCs lacking the L-side monomeric bacteriochlorophyll chromophore result from mutation of the n...
The crucibles that bore out early building blocks of life may have been, in many cases, modest puddles.Now, researchers working with that hypothesis have achieved a significant advancement t...
Estimation in semiparametric models with missing data
Copulas imputation kernel smoothing missing at random nuisance function partially linear model
2016/1/20
This paper considers the problem of parameter estimation in a general class of semiparametric models when observations are subject to missingness at random.The semiparametric models allow for estimati...
Seven missing damaging earthquakes in Upper Valtiberina (Central Italy) in 16th-18th century: research strategies and historical sources
missing earthquakes historical seismology Italian earthquake catalogues Upper Valtiberina
2015/9/8
The Italian earthquake catalogue is considered to be fairly complete starting from the 17th century and for classes
of earthquakes of magnitude greater than 5.5. However, dedicated historical researc...
Looking for missing earthquake traces in the Ferrara-Modena plain: an update on historical seismicity
Historical seismology Surveys, measurements, and monitoring Seismic risk General or miscellaneous Seismological data
2015/8/26
According to the latest issue of the Italian seismic catalogue [Rovida et al. 2011], the area most affected by the May-June 2012 Emilia sequence [for an overview, vide Galli et al. 2012; Tertulliani e...
Imputing Missing Data for Gene Expression Arrays
Imputing Missing Data Gene Expression Arrays
2015/8/21
Here we describe three different methods for imputation.The first is based on a reduced rank SVD of the expression matrix, the second is based on K-nearest neighbor averaging, and the third is based o...
Stochastic Quantification of Missing Mechanisms in Dynamical Systems
ynamical Systems Missing Mechanisms
2015/4/3
Due to lack of knowledge:
Missing mechanisms (ignored “too small" or “too fast" or
“unimportant" processes)
Unresolved scales (not represented in models)
Model uncertainties
Simulation of soft X-ray emission lines from the missing baryons
theory diff use radiation large-scale structure of universe
2014/12/24
We study the soft X-ray emission (0.1-1 keV) from the warm-hot intergalactic medium (WHIM) in a hydrodynamic simulation of a cold dark matter universe. Our main goal is to investigate how such emissio...
Missing-iron problem and Type Ia supernova enrichment of hot gas in galactic spheroids
hot gas galactic spheroids
2014/12/22
Type Ia supernovae (Ia SNe) provide a rich source of iron for hot gas in galactic stellar spheroids. However, the expected supersolar iron abundance of the hot gas is not observed. Instead, X-ray obse...
HST Pa Survey of the Galactic Center – Searching the missing young stellar populations within the Galactic Center
star formation process
2014/12/20
We present preliminary results of our \hst Pa$\alpha$ survey of the Galactic Center (\gc), which maps the central 0.65$\times$0.25 degrees around Sgr A*. This survey provides us with a more complete i...