14C Age Measurements of Single-Year Tree Rings of Old Wood Samples 22,000 14C Years BP

Radiocarbon ages of single-year tree rings were measured for Kaminoyama wood samples using accelerator mass spectrometry (AMS) in 2 Japanese facilities, MALT and JAEA, in order to investigate the periodic variation of 14C concentrations relating to the 11-yr solar cycle near 26,000 yr BP. Eight sequential measurements of 14C ages were carried out for a set of 13 alternate single-year tree rings covering 26 yr. Averages of the 5 data sets in MALT and 3 data sets in JAEA were 22,146 ± 50 and 22,407 ± 58 14C yr BP, respectively, indicating an offset of 260 ± 77 14C yr. Multiple sequential measurements are advantageous for evaluating offsets. The standard deviation of the residuals of 14C ages from the averages in each data set was 118 14C yr, in contrast to that of 234 14C yr for the combined data sets due to an elimination effect in the offsets. The profiles of weighted mean values for the residuals of 14C ages showed similar enhancements with a width of ∼12 yr for measurements in the 2 facilities. This indicates the reproducibility of the multiple sequential measurements. In the profile for the combined 8 data sets, the 14C enhancement was 73 ± 36 14C yr from the average.

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Comparison of 14C Ages Between LSC and AMS Measurements of Choukai Jindai Cedar Tree Rings at 2600 cal BP

Radiocarbon ◽

10.1017/s0033822200045987 ◽

2010 ◽

Vol 52 (3) ◽

pp. 895-900 ◽

Cited By ~ 5

Author(s):

Yui Takahashi ◽

Hirohisa Sakurai ◽

Kayo Suzuki ◽

Taiichi Sato ◽

Shuichi Gunji ◽

...

Keyword(s):

Mass Spectrometry ◽

Tree Rings ◽

Liquid Scintillation ◽

Measurement Methods ◽

Scintillation Counting ◽

Age Difference ◽

Data Sets ◽

Data Set ◽

The Difference ◽

Good Agreement

Radiocarbon ages of Choukai Jindai cedar tree rings growing in the excess era of 14C concentrations during 2757–2437 cal BP were measured using 2 types of 14C measurement methods, i.e. liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS). The difference between the 2 methods is 3.7 ± 5.2 14C yr on average for 61 single-year tree rings, indicating good agreement between the methods. The Choukai data sets show a small sharp bump with an average 14C age of 2497.1 ± 3.0 14C yr BP during 2650–2600 cal BP. Although the profile of the Choukai LSC data set compares well with that of IntCal04, having a 14C age difference of 4.6 ± 5.3 14C yr on average, the Choukai LSC 14C ages indicate variability against the smoothed profile of IntCal04.

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Precise Comparison of 14C Ages from Choukai Jindai Cedar with IntCal04 Raw Data

Radiocarbon ◽

10.1017/s0033822200056332 ◽

2010 ◽

Vol 52 (4) ◽

pp. 1599-1609 ◽

Cited By ~ 10

Author(s):

Kayo Suzuki ◽

Hirohisa Sakurai ◽

Yui Takahashi ◽

Taiichi Sato ◽

Shuichi Gunji ◽

...

Keyword(s):

Mass Spectrometry ◽

Tree Rings ◽

Accelerator Mass Spectrometry ◽

Correlation Coefficients ◽

Data Sets ◽

Calibration Data ◽

Data Set ◽

Raw Data ◽

Temporal Profile ◽

Temporal Profiles

We measured the radiocarbon ages of 165 single-year tree rings from a Japanese Choukai Jindai cedar using accelerator mass spectrometry (AMS). By wiggle-matching the Choukai_AMS data set to the IntCal04 calibration data using OxCal v 3.10 and using the variation of the correlation coefficients between the Choukai_AMS and IntCal04 data sets, we precisely re-estimated that the 321 Choukai Jindai cedar tree rings range from 780 to 460 cal BC with an accuracy of 8 yr. The Choukai_AMS data set is older than the 3 raw data sets of European tree rings that comprise IntCal04. The Belfast and Seattle data sets are younger by −21.3 ± 5.5 and −22.7 ± 5.6 14C yr, respectively. The Choukai Jindai cedar is ∼22 14C yr older than the European tree rings, which is equivalent to an offset of −2.8‰ in 14C. In addition, the Choukai_AMS data set correlates well with the Belfast and Seattle data sets, with correlation coefficients of 0.89 and 0.68, respectively, between the temporal profiles. Hence, the temporal profile of the Choukai 14C ages shows a global variation.

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Matching Dendrochronological Dates with the Southern Hemisphere 14C Bomb Curve to Confirm Annual Tree Rings in Pseudolmedia rigida from Bolivia

Radiocarbon ◽

10.2458/azu_rc.57.18192 ◽

2015 ◽

Vol 57 (1) ◽

pp. 1-13 ◽

Cited By ~ 14

Author(s):

Laia Andreu-Hayles ◽

Guaciara M Santos ◽

David A Herrera-Ramírez ◽

Javier Martin-Fernández ◽

Daniel Ruiz-Carrascal ◽

...

Keyword(s):

Southern Hemisphere ◽

Tree Rings ◽

Geographic Location ◽

Data Sets ◽

Atmospheric Concentration ◽

Concentration Data ◽

Data Set ◽

Dendrochronological Analysis ◽

Before And After ◽

Ring Analysis

This study used high-precision radiocarbon bomb-pulse dating of selected wood rings to provide an independent validation of the tree growth periodicity of Pseudolmedia rigida (Klotzsch & H. Karst) Cuatrec. from the Moraceae family, collected in the Madidi National Park in Bolivia. 14C content was measured by accelerator mass spectrometry (AMS) in 10 samples from a single tree covering over 70 yr from 1939 to 2011. These preliminary calendar dates were determined by dendrochronological techniques and were also used to select the samples for 14C AMS. In order to validate these preliminary dates using the established Southern Hemisphere (SH) 14C atmospheric concentration data set, the targeted rings were selected to be formed during periods before and after the 14C bomb spike nuclear tests (i.e. 1950s–1960s). The excellent agreement of the dendrochronological dates and the 14C signatures in tree rings associated with the same dates provided by the bomb-pulse 14C atmospheric values for the SH (SHCal zone 1–2) confirms the annual periodicity of the observed growth layers, and thus the high potential of this species for tree-ring analysis. The lack of discrepancies between both data sets also suggests that there are no significant latitudinal differences between the 14C SHCal zone 1–2 curve and the 14C values obtained from the selected tree rings at this geographic location (14°33′S, 68°49′W) in South America. The annual resolution of P. rigida tree rings opens the possibility of broader applications of dendrochronological analysis for ecological and paleoclimatic studies in the Bolivian tropics, as well as the possibility of using wood samples from some tree species from this region to improve the quality of the bomb-pulse 14C SHCal curve at this latitude.

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Combining cross-crystal averaging and MRSAD to phase a 4354-amino-acid structure

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798315023566 ◽

2016 ◽

Vol 72 (2) ◽

pp. 182-191

Author(s):

Jason Nicholas Busby ◽

J. Shaun Lott ◽

Santosh Panjikar

Keyword(s):

Radiation Damage ◽

Model Building ◽

Data Sets ◽

Low Resolution ◽

Data Set ◽

C Protein ◽

Large Size ◽

Anomalous Signal ◽

Difference Fourier ◽

Combined Data

The B and C proteins from the ABC toxin complex ofYersinia entomophagaform a large heterodimer that cleaves and encapsulates the C-terminal toxin domain of the C protein. Determining the structure of the complex formed by B and the N-terminal region of C was challenging owing to its large size, the non-isomorphism of different crystals and their sensitivity to radiation damage. A native data set was collected to 2.5 Å resolution and a non-isomorphous Ta6Br12-derivative data set was collected that showed strong anomalous signal at low resolution. The tantalum-cluster sites could be found, but the anomalous signal did not extend to a high enough resolution to allow model building. Selenomethionine (SeMet)-derivatized protein crystals were produced, but the high number (60) of SeMet sites and the sensitivity of the crystals to radiation damage made phasing using the SAD or MAD methods difficult. Multiple SeMet data sets were combined to provide 30-fold multiplicity, and the low-resolution phase information from the Ta6Br12data set was transferred to this combined data set by cross-crystal averaging. This allowed the Se atoms to be located in an anomalous difference Fourier map; they were then used inAuto-Rickshawfor multiple rounds of autobuilding and MRSAD.

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Evolution and phylogenetic significance of cardioidean shell microstructure (Mollusca, Bivalvia)

Journal of Paleontology ◽

10.1017/s002233600003969x ◽

2001 ◽

Vol 75 (3) ◽

pp. 607-643 ◽

Cited By ~ 22

Author(s):

Jay A. Schneider ◽

Joseph G. Carter

Keyword(s):

Phylogenetic Relationships ◽

Outer Shell ◽

Data Sets ◽

Shell Layer ◽

Shell Microstructure ◽

Data Set ◽

Fracture Control ◽

Selection For ◽

Morphologic Data ◽

Combined Data

The shell microstructure of Carboniferous and Triassic permophorids; Triassic and Recent carditids; Devonian, Carboniferous, and Triassic crassatelloideans; and Jurassic through Recent cardioideans is examined in a phylogenetic context, using separate microstructural and morphologic data sets, as well as a combined data set. The microstructural and morphologic data sets are significantly incongruent, but the combined data set suggests that modiomorphoideans (modiomorphids and permophorids) are basal to crassatelloideans; crassatelloideans are basal to carditids (includingSeptocardia), and carditids are basal to cardiids. On the other hand, the possibility of direct permophorid ancestry for the carditid-cardiid clade cannot be excluded, as suggested by the retention of permophorid-like matted (transitional nacreous-porcelaneous) structure in some early carditids and cardiids. In the absence of stratigraphic data and other evidence for phylogenetic relationships, shell microstructure offers limited potential for assessing subfamily-level phylogenetic relationships within the Cardioidea. This is because of microstructural convergences reflecting biomechanical adaptations for fracture control and abrasion resistance, and possibly also selection for metabolic economy of secretion in tropical, oligotrophic habitats. General evolutionary trends in cardiid shell microstructure are nevertheless apparent: Cretaceous cardiids completely replaced an ancestral laminar, matted structure in their inner shell layer with non-laminar porcelaneous structures; evolved better defined CL structure, stronger reflection of the shell margins, and increased thickness or secondary loss of the ancestral prismatic outer shell layer; and, inProtocardia(Pachycardium)stantoni, added inductural deposition. Some Cenozoic cardiids then evolved wider first-order crossed lamellae, non-denticular composite prisms, composite fibrous prisms, ontogenetic submergence of a juvenile non-denticular composite prismatic outer shell layer into the CL middle shell layer, or ontogenetic submergence of the inner part of a juvenile fibrous prismatic outer shell layer into the CL middle shell layer.The shell microstructure ofHemidonax donaciformisis unusual for a cardioidean, and suggests closer affinities with the superfamily Tellinoidea than with the superfamily Cardioidea.Extensive inductural deposits inProtocardia(Pachycardium)stantoniraise the possibility that photosymbiosis evolved among some Mesozoic members of the Protocardiinae, thereby increasing the likelihood that this feature has evolved several times independently in the Cardiidae.Cemented, calcareous periostracal granules or spines are known to occur in modiolopsoideans, mytiloideans, modiomorphids, permophorids, trigonioids, astartids, cardiids, myoids, pholadomyoids, and septibranchoids. Consequently, the presence of these structures is not necessarily indicative of close anomalodesmatan affinities.

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Geostatistical Joint Interpretation of Gravity and Magnetotelluric Data of the US Cordillera

10.5194/egusphere-egu21-45 ◽

2021 ◽

Author(s):

Mohammad Shehata ◽

Hideki Mizunaga

Keyword(s):

Gravity Data ◽

Three Dimensional ◽

Data Sets ◽

Spatial Expansion ◽

Magnetotelluric Data ◽

Data Set ◽

Entire Area ◽

Mean Values ◽

Local Means ◽

The Us

<p>Long-period magnetotelluric and gravity data were acquired to investigate the US cordillera's crustal structure. The magnetotelluric data are being acquired across the continental USA on a quasi-regular grid of &#8764;70 km spacing as an electromagnetic component of the National Science Foundation EarthScope/USArray Program. International Gravimetreique Bureau compiled gravity Data at high spatial resolution. Due to the difference in data coverage density, the geostatistical joint integration was utilized to map the subsurface structures with adequate resolution. First, a three-dimensional inversion of each data set was applied separately.</p><p>The inversion results of both data sets show a similarity of structure for data structuralizing. The individual result of both data sets is resampled at the same locations using the kriging method by considering each inversion model to estimate the coefficient. Then, the Layer Density Correction (LDC) process's enhanced density distribution was applied to MT data's spatial expansion process. Simple Kriging with varying Local Means (SKLM) was applied to the residual analysis and integration. For this purpose, the varying local means of the resistivity were estimated using the corrected gravity data by the Non-Linear Indicator Transform (NLIT), taking into account the spatial correlation. After that, the spatial expansion analysis of MT data obtained sparsely was attempted using the estimated local mean values and SKLM method at the sections where the MT survey was carried out and for the entire area where density distributions exist. This research presents the integration results and the stand-alone inversion results of three-dimensional gravity and magnetotelluric data.</p>

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Assessing the usefulness of histone H3, U2 snRNA and 28S rDNA in analyses of polychaete relationships

Australian Journal of Zoology ◽

10.1071/zo99026 ◽

1999 ◽

Vol 47 (5) ◽

pp. 499 ◽

Cited By ~ 50

Author(s):

S. Brown ◽

G. Rouse ◽

P. Hutchings ◽

D. Colgan

Keyword(s):

Maximum Parsimony ◽

Sequence Data ◽

Histone H3 ◽

28S Rdna ◽

Maximum Parsimony Analysis ◽

Data Sets ◽

Data Set ◽

U2 Snrna ◽

Dna Sequence Data ◽

Combined Data

DNA sequence data from for histone H3 (34 species), U2 snRNA (34 species) and two segments (D1 and D9–10 expansion regions) of 28S rDNA (28 and 26 species, respectively) have been collected to investigate the relationships of polychaetes. Representatives of all of the major morphologically identified clades were used, as well as members of the Sipuncula, Echiura, Turbellaria, Clitellata and Siboglinidae (formerly the phyla Pogonophora and Vestimentifera). Maximum parsimony analyses of the separate data sets gave conflicting results and none conformed closely to previous results based on morphology. Instead each data set provided corroboration of a few of the morphological groupings, usually pairing, though inconsistently, members of the same family. Higher groupings proposed on morphological grounds were rarely recovered. Maximum parsimony analysis of the combined data, excluding areas of uncertain alignment, recovered some morphological groupings such as Cirratulidae, Terebellidae, scale worms and eunicimorphs, and did not significantly contradict others. However, some expected groupings were not recovered. Surprisingly, the fanworms (Sabellidae and Serpulidae) were not shown as sister taxa, and monophyly of Phyllodocida, a morphologically well corroborated clade, required four more steps than most parsimonious trees. Aciculata was not seen in our analyses, although it was the most strongly supported large clade in Rouse and Fauchald (1997, Cladistics and polychaetes. Zoologica Scripta 26, 138–204). Trees constrained to show Aciculata as monophyletic were 18 steps longer than the most parsimonious trees. If trees are rooted on sipunculans rather than the nematode, Aciculata is nearly recovered, being rendered paraphyletic by the inclusion of the sister-pair of Oweniidae and Chaetopteridae. As suggested by some recent morphological and molecular analyses, Siboglinidae and Clitellata may well have sister groups among polychaetes. The morphologically aberrant Sternaspidae are closest to members of Terebellida in the present analyses, supporting the placement of Rouse and Fauchald. Interesting results deserving further assessment concern the placement of Chaetopteridae, Oweniidae and Sipuncula.

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Effective inhibition of MYC-amplified Group 3 medulloblastoma through targeting translation machinery eIF4F complex

10.21203/rs.3.rs-19096/v1 ◽

2020 ◽

Author(s):

Yang Zhao ◽

Tiantian Li ◽

Shuaiwei Tian ◽

Wei Meng ◽

Jian Yang ◽

...

Keyword(s):

Mass Spectrometry ◽

Therapeutic Target ◽

Transcript Level ◽

Data Sets ◽

Data Set ◽

Eif4f Complex ◽

Inhibitory Mechanisms ◽

Promising Therapeutic Target ◽

Group 3 ◽

Highly Correlated

Abstract Background: Medulloblastoma (MB) consists of four major molecular subtypes and group 3 subtype (G3) is the most aggressive one. MYC amplification tends to happen in G3 MB and those patients exhibit the worse prognosis and need novel effective therapeutic approach most urgently. MYC has been shown to be the driver as well as crucial dependency for MYC-amplified G3-MB, thus serving as a promising therapeutic target. Methods: In this study, we tested inhibiting MYC translation in MYC-amplified G3-MB by targeting eIF4F complex. We analyzed multiple MB tumor data sets to identify potential therapeutic target of eIF4F components and utilized genetic or pharmacological approaches for validation. The relevant inhibitory mechanisms were further investigated by Western blot and whole lysate mass spectrometry assays to confirm the targeting of MYC translation. Results: Tumor data set analyses identified eIF4A1, a subunit of eIF4F complex, which was significantly upregulated in G3-MB compared to normal cerebellum and highly correlated with MYC at transcript level. Targeting eIF4A1 with CRISPR/Cas9 approach or small-molecule inhibitor Silvestrol effectively attenuated growth of multiple preclinical models through blocking proliferation and inducing apoptosis. Mechanistically, Silvestrol treatment effectively inhibited MYC expression at protein level and MYC amplification was shown to sensitize MB cells to eIF4A1 inhibition. Moreover, whole proteome mass spectrometry analyses demonstrated additional biological functions or pathways affected by eIF4A1 inhibition, which could help in better understanding its inhibitory mechanisms and revealing combinatory strategies. Conclusion: It is shown in our study that targeting MYC translation by eIF4A1 inhibition could be an effective therapeutic strategy against MYC-amplified G3-MB.

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Retrieval of ozone profiles from OMPS limb scattering observations

10.5194/amt-2017-301 ◽

2017 ◽

Cited By ~ 1

Author(s):

Carlo Arosio ◽

Alexei Rozanov ◽

Elizaveta Malinina ◽

Kai-Uwe Eichmann ◽

Thomas von Clarmann ◽

...

Keyword(s):

Visible Spectral Range ◽

Retrieval Algorithm ◽

Tropical Region ◽

Data Sets ◽

Absorption Bands ◽

Data Set ◽

Northern Latitudes ◽

The University ◽

Combined Data ◽

Good Agreement

Abstract. This study describes a retrieval algorithm developed at the University of Bremen to retrieve vertical profiles of ozone from limb observations performed by the Ozone Mapper and Profiler Suite (OMPS). This algorithm was originally developed for use with data from the SCIAMACHY instrument. As both instruments make limb measurements of the scattered solar radiation in the ultraviolet and visible spectral range, an overarching objective of the study is to facilitate the provision of consolidated and consistent ozone profiles from the two satellites and to produce a combined data set. The optimization of the retrieval algorithm for OMPS takes into account the instrument-specific spectral coverage by exploiting information from spectral windows in the Hartley, Huggins and Chappuis ozone absorption bands. Thereby, ozone concentrations in the 12–60 km altitude range can be retrieved. Observations at altitudes where the measurements are contaminated by clouds are rejected by applying a cloud filter. An independent aerosol retrieval is performed beforehand and its results are used to account for the aerosol load in the stratosphere during the ozone retrieval. Results for seven months of data (July 2016–January 2017) are compared and validated against independent data sets from both satellite-based and balloon-borne measurements, indicating a good agreement. Between 20 and 50 km, the OMPS ozone profiles typically agree with the MLS v4.2 results within 5–10 %, with the exception of high northern latitudes (> 70° N above 40 km) and the tropical lower stratosphere. The comparison of OMPS profiles with those from ozonesondes shows an agreement within ±5 % between 14 and 30 km at northern mid-latitudes. At southern mid-latitudes, an agreement within 5–10 % is achieved, although these results are less reliable because of a limited number of available coincidences. An unexpected bias of approximately 10 % is detected in the tropical region at all altitudes. The processing of the 2013 data set using the same retrieval settings and its validation against ozonesondes reveals a much smaller bias; possible reasons are under investigation.

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Reservoir-parameter identification using minimum relative entropy-based Bayesian inversion of seismic AVA and marine CSEM data

Geophysics ◽

10.1190/1.2348770 ◽

2006 ◽

Vol 71 (6) ◽

pp. O77-O88 ◽

Cited By ~ 32

Author(s):

Zhangshuan Hou ◽

Yoram Rubin ◽

G. Michael Hoversten ◽

Don Vasco ◽

Jinsong Chen

Keyword(s):

Relative Entropy ◽

Joint Inversion ◽

Parameter Estimates ◽

Data Sets ◽

Data Set ◽

Mean Values ◽

Prior Probabilities ◽

Reservoir Fluid ◽

Minimum Relative Entropy ◽

Reservoir Parameter

A stochastic joint-inversion approach for estimating reservoir-fluid saturations and porosity is proposed. The approach couples seismic amplitude variation with angle (AVA) and marine controlled-source electromagnetic (CSEM) forward models into a Bayesian framework, which allows for integration of complementary information. To obtain minimally subjective prior probabilities required for the Bayesian approach, the principle of minimum relative entropy (MRE) is employed. Instead of single-value estimates provided by deterministic methods, the approach gives a probability distribution for any unknown parameter of interest, such as reservoir-fluid saturations or porosity at various locations. The distribution means, modes, and confidence intervals can be calculated, providing a more complete understanding of the uncertainty in the parameter estimates. The approach is demonstrated using synthetic and field data sets. Results show that joint inversion using seismic and EM data gives better estimates of reservoir parameters than estimates from either geophysical data set used in isolation. Moreover, a more informative prior leads to much narrower predictive intervals of the target parameters, with mean values of the posterior distributions closer to logged values.

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