11,303 research outputs found

    Effects of seawater pCO2 and temperature on calcification and productivity in the coral genus Porites spp. : an exploration of potential interaction mechanisms

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    This work was supported by the UK Natural Environment Research Council (Award NE/I022973/1) to AAF and NA.Understanding how rising seawater pCO2 and temperatures impact coral aragonite accretion is essential for predicting the future of reef ecosystems. Here we report 2 long term (10-11 month) studies assessing the effects of temperature (25 and 28°C) and both high and low seawater pCO2 (180-750 μatm) on the calcification, photosynthesis and respiration of individual massive Porites spp. genotypes. Calcification rates were highly variable between genotypes but high seawater pCO2 reduced calcification significantly in 4 of 7 genotypes cultured at 25°C but in only 1 of 4 genotypes cultured at 28°C. Increasing seawater temperature enhanced calcification in almost all corals but the magnitude of this effect was seawater pCO2 dependent. The 3°C temperature increase enhanced calcification rate on average by 3% at 180 μatm, by 35% at 260 μatm and by >300% at 750 μatm. The rate increase at high seawater pCO2 exceeds that observed in inorganic aragonites. Responses of gross/net photosynthesis and respiration to temperature and seawater pCO2 varied between genotypes but rates of all these processes were reduced at the higher seawater temperature. Increases in seawater temperature, below the thermal stress threshold, may mitigate against ocean acidification in this coral genus but this moderation is not mediated by an increase in net photosynthesis. The response of coral calcification to temperature cannot be explained by symbiont productivity or by thermodynamic and kinetic influences on aragonite formation.Publisher PDFPeer reviewe

    Expression of PEG11 and PEG11AS transcripts in normal and callipyge sheep

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    BACKGROUND: The callipyge mutation is located within an imprinted gene cluster on ovine chromosome 18. The callipyge trait exhibits polar overdominant inheritance due to the fact that only heterozygotes inheriting a mutant paternal allele (paternal heterozygotes) have a phenotype of muscle hypertrophy, reduced fat and a more compact skeleton. The mutation is a single A to G transition in an intergenic region that results in the increased expression of several genes within the imprinted cluster without changing their parent-of-origin allele-specific expression. RESULTS: There was a significant effect of genotype (p < 0.0001) on the transcript abundance of DLK1, PEG11, and MEG8 in the muscles of lambs with the callipyge allele. DLK1 and PEG11 transcript levels were elevated in the hypertrophied muscles of paternal heterozygous animals relative to animals of the other three genotypes. The PEG11 locus produces a single 6.5 kb transcript and two smaller antisense strand transcripts, referred to as PEG11AS, in skeletal muscle. PEG11AS transcripts were detectable over a 5.5 kb region beginning 1.2 kb upstream of the PEG11 start codon and spanning the entire open reading frame. Analysis of PEG11 expression by quantitative PCR shows a 200-fold induction in the hypertrophied muscles of paternal heterozygous animals and a 13-fold induction in homozygous callipyge animals. PEG11 transcripts were 14-fold more abundant than PEG11AS transcripts in the gluteus medius of paternal heterozygous animals. PEG11AS transcripts were expressed at higher levels than PEG11 transcripts in the gluteus medius of animals of the other three genotypes. CONCLUSIONS: The effect of the callipyge mutation has been to alter the expression of DLK1, GTL2, PEG11 and MEG8 in the hypertrophied skeletal muscles. Transcript abundance of DLK1 and PEG11 was highest in paternal heterozygous animals and exhibited polar overdominant gene expression patterns; therefore, both genes are candidates for causing skeletal muscle hypertrophy. There was unique relationship of PEG11 and PEG11AS transcript abundance in the paternal heterozygous animals that suggests a RNA interference mechanism may have a role in PEG11 gene regulation and polar overdominance in callipyge sheep

    Complete Transcript of the 1894 Journal

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    Shape of the 8B Alpha and Neutrino Spectra

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    The beta-delayed alpha spectrum from the decay of 8B has been measured with a setup that minimized systematic uncertainties that affected previous measurements. Consequently the deduced neutrino spectrum presents much smaller uncertainties than the previous recommendation. The 8B neutrino spectrum is found to be harder than previously recommended with about (10-20)% more neutrinos at energies between 12-14 MeV. The efficiencies of the 37Cl, 71Ga, 40Ar, and SuperKamiokande detectors are respectively, 3.6%, 1.4%, 5.7% and 1.8% larger than previously thought.Comment: 4 pages, 5 figure

    The Discriminant Formula for the Determination of Sex of Adults in A Nigerian Population (Using Pelvic Radiographs)

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    Identification of sex in human skeletal remains is an important component and frequently the starting point of many forensic anthropological investigations. This study was carried out to document the determination of sex by discriminant formula using the pelvic radiographs of Nigerian adults. Measurements were carried out on the pelvis. Pelvic radiographs of 500 adult Nigerians of known sex, age range 18-75 years (comprising 250 males and 250 females) were measured in the antero-posterior position using a digital vernier calliper. The data was analysed using z-test. The results showed that the mean values for the Ischial length and Pubic length in males were 86.82±8.25mm and 76.41±8.91mm respectively while in females the Ischial length and Pubic length were 80.62±7.66mm and 84.58±8.80mm respectively. 4% males and 19% females were identified for ischial length and 15% males and 42% females were identified for pubic length. The mean value for pelvic height in males and females were 236.70±12.51mm and 223.02±12.18mm respectively, the demarking points identified 29% males and 32% females, while the mean value for midpubic width in males and females were 25.94± 4.54mm and 30.09± 3.67mm respectively, the demarking points identified 40% and 65% females. The mean values for ischiopubic and pelvic height/midpubic width were statistically significant (P&lt;0.05). The mean values of the pelvic height/midpubic index were 9.35 ± 1.38 in males and 7.49 ± 0.82 in females. The demarking points identified 72% males and 75% females. While the mean values of the ischiopubic index in males and females were 88.46±9.26 in males and 114.67±99.28 in females, the demarking points identified 56% males and 84% females. It was observed that the males had higher pelvic height and ischial length than females, while the females had longer pubic length and mid pubic width which contributed to the females having wider pelvis. The accurate determination of sex and race are important tools to forensic Scientists and physical anthropologists. Keywords: Pelvis, Radiographs, Sex determination, Nigerian population

    Mid-infrared frequency comb generation and spectroscopy with few-cycle pulses and chi((2)) nonlinear optics

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    FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPThe mid-infrared atmospheric window of 3-5.5 mu m holds valuable information regarding molecular composition and function for fundamental and applied spectroscopy. Using a robust, mode-locked fiberlaser source of < U fs pulses in the near infrared, we exp1241316FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2018/26673-5The authors acknowledge support from the National Institute of Standards and Technology, the DARPA SCOUT Program, the National Science Foundation (Grand No. 1708743), and the Air Force Office of Scientific Research (Grants No. FA9550-16-1-0016 and No. FA

    Influences of coral genotype and seawater pCO2 on skeletal Ba/Ca and Mg/Ca in cultured massive Porites spp. corals

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    This work was supported by the UK Natural Environment Research Council (award NE/I022973/1) to AAF and NA.Coral skeletal Ba/Ca is a proxy for seawater Ba/Ca, used to infer oceanic upwelling and terrigenous runoff while [Mg2+] is implicated in the control of coral biomineralisation. We cultured large individuals (>12 cm diameter) of 3 genotypes of massive adult Porites spp. corals over a range of seawater pCO2 to test how atmospheric CO2 variations affect skeletal Ba/Ca and Mg/Ca. We identified the skeleton deposited after a 5 month acclimation period and analysed the skeletal Ba/Ca and Mg/Ca by secondary ion mass spectrometry. Skeletal Mg/Ca varies significantly between some duplicate colonies of the same coral genotype hampering identification of genotype and seawater pCO2 effects. Coral aragonite:seawater Ba/Ca partition coefficients (KD Ba/Ca) do not vary significantly between duplicate colonies of the same coral genotype. We observe large variations in KD Ba/Ca between different massive Porites spp. coral genotypes irrespective of seawater pCO2. These variations do not correlate with coral calcification, photosynthesis or respiration rates or with skeletal KD Mg/Ca or KD Sr/Ca. Seawater pCO2 does not significantly affect KD Ba/Ca in 2 genotypes but KD Ba/Ca is significantly higher at 750 μatm seawater pCO2 than at 180 μatm in 1 P. lutea genotype. Genotype specific variations in KD Ba/Ca between different Porites spp. could yield large errors (~250%) in reconstructions of seawater Ba when comparing Ba/Ca between corals. Analysis of fossil coral specimens deposited at low seawater pCO2, may underestimate past seawater Ba/Ca and ocean upwelling/freshwater inputs when compared with modern specimens but the effect is small in comparison with the observed difference between coral genotypes.PostprintPeer reviewe

    Study of a Large NaI(Tl) Crystal

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    Using a narrow band positron beam, the response of a large high-resolution NaI(Tl) crystal to an incident positron beam was measured. It was found that nuclear interactions cause the appearance of additional peaks in the low energy tail of the deposited energy spectrum

    Differential Response of Bacterial Microdiversity to Simulated Global Change

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    ACKNOWLEDGMENTS UC Irvine and the LRGCE are located on the ancestral homelands of the Indigenous Kizh and Acjachemen nations. We thank Alejandra Rodriguez Verdugo, Katrine Whiteson, Kendra Walters, Cynthia Rodriguez, Kristin Barbour, Alberto Barron Sandoval, Joanna Wang, Joia Kai Capocchi, Pauline Uyen Phuong Nguyen, Khanh Thuy Huynh, and Clara Barnosky for their input on analyses and previous drafts and for laboratory help. This work was supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research grants DE-SC0016410 and DE-SC0020382.Peer reviewedPublisher PD
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