University of Hawaii at Manoa

About: University of Hawaii at Manoa is a education organization based out in Honolulu, Hawaii, United States. It is known for research contribution in the topics: Population & Sea surface temperature. The organization has 13693 authors who have published 25161 publications receiving 1023924 citations.

Effects of naturally occurring compounds on fibril formation and oxidative stress of beta-amyloid.

Abstract: Beta-amyloid (betaA)-induced oxidative toxicity on neuronal cells is a principal route in Alzheimer's disease (AD), and its toxicity occurs after fibril formation. Inhibitory or promoting effects of naturally occurring compounds on betaA fibril formation were evaluated. Among 214 tested compounds, curcuminoids, flavone type flavonoids, and naphthoquinones were shown to be potent inhibitors of betaA fibrilization. The addition of the curcuminoids, curcumin, demethoxycurcumin, and bisdemethoxycurcumin strongly inhibited betaA fibril formation. Flavonoids such as quercetin, rhamnetin, and fisetin strongly inhibited betaA fibril formation. Limonoids, cinnamic acids, and catechins enhanced fibril formation in vitro. Anthothecol possessed the most enhancing activity on fibril formation of the compounds tested. On the other hand, it was found that curcuminoids showed cytotoxicity with the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay and did not protect HT22 murine neuroblastoma cells from betaA(25-35) insult. Two flavone type flavonoids, morin and quercetin, exhibited no cytotoxicity and strongly protected HT22 murine neuroblastoma cells from betaA(25-35) oxidative attack. Conclusively, morin or quercetin could be a key molecule for the development of therapeutics for AD.

The Mars Odyssey Gamma-Ray Spectrometer Instrument Suite

Abstract: The Mars Odyssey Gamma-Ray Spectrometer is a suite of three different instruments, a gamma subsystem (GS), a neutron spectrometer, and a high-energy neutron detector, working together to collect data that will permit the mapping of elemental concentrations on the surface of Mars. The instruments are complimentary in that the neutron instruments have greater sensitivity to low amounts of hydrogen, but their signals saturate as the hydrogen content gets high. The hydrogen signal in the GS, on the other hand, does not saturate at high hydrogen contents and is sensitive to small differences in hydrogen content even when hydrogen is very abundant. The hydrogen signal in the neutron instruments and the GS have a different dependence on depth, and thus by combining both data sets we can infer not only the amount of hydrogen, but constrain its distribution with depth. In addition to hydrogen, the GS determines the abundances of several other elements. The instruments, the basis of the technique, and the data processing requirements are described as are some expected applications of the data to scientific problems.

Diurnal Precipitation Regimes in the Global Tropics

Abstract: Diurnal variations of the global tropical precipitation are documented by using two complementary Tropical Rainfall Measuring Mission (TRMM) datasets (3B42 and 3G68) for 1998–2006 in an attempt to provide a unified view of the diurnal cycle and a metric for evaluating numerical model performance. The 3B42 data have better spatial coverage; the 3G68 data offer more accurate diurnal phase information. The first and second empirical orthogonal function (EOF) modes represent the diurnal cycle and account for 89% of the total variance in 3B42. The third and fourth EOF modes, which account for 10% of the total variance, represent the semidiurnal cycle. Both datasets yield consistent spatial structures and temporal evolution, but they have different advantages: the patterns derived from 3B42 exhibit less noise, while 3G68 yields an arguably more accurate diurnal phase. The diurnal phase derived from 3G68 systematically leads 3B42 by about 3 h. Three tropical diurnal cycle regimes (oceanic, continental, ...

Emplacement of continental flood basalt lava flows

Abstract: We propose that continental flood basalt (CFB) lavas were predominantly emplaced as inflated compound pahoehoe flow fields via prolonged, episodic eruptions Our most detailed observations come from the ∼14,7 Ma Roza flow field of the Columbia River Basalt (CRB) Group The Roza flow field seems to be typical of many flood basalt lavas Individual flows show a wide range of pahoehoe surface features and a three-part internal structure in vesicularity and other textural parameters This three-fold division into an upper crust, core, and basal crust appears to be diagnostic of the inflation process and is ubiquitous in basaltic lava flows over a remarkable range of sizes The pahoehoe surface features and indications of inflation are inconsistent with rapid emplacement of these lava flows Instead, we interpret the observations to imply that the Roza, and other CFB flows, were emplaced over an extended period of time From the thickness of the upper crust, which we suggest formed while the flow was actively inflating, and an empirical expression for the rate of crust growth of Hawaiian inflated sheet flows, we estimate that individual Roza flows were emplaced over 5 to 50 months and that the Roza flow field was constructed over a period of 6 to 14 years However, even with this longer eruption duration, the average lava effusion rate of ∼4000 m 3 /s is similar to that of the highest-effusion-rate eruption in recorded history (the 1783-4 Laki eruption in Iceland) Our observations of lava characteristics in other CRB flows and in the Deccan Traps suggest that this emplacement style is typical of many, if not most, CFB flows Initial estimates of the volatile release from the Roza eruption indicate that prodigious amounts of S, Cl, and F were injected into the upper troposphere and lowermost stratosphere; thus this single flood basalt eruption could have had a significant effect on the global atmosphere If other flood basalt eruptions produced similar amounts of volatiles, volatile release might provide a link between flood basalt eruptions and mass extinctions

A common variant at the TERT-CLPTM1L locus is associated with estrogen receptor-negative breast cancer

Abstract: Estrogen receptor (ER)-negative breast cancer shows a higher incidence in women of African ancestry compared to women of European ancestry. In search of common risk alleles for ER-negative breast cancer, we combined genome-wide association study (GWAS) data from women of African ancestry (1,004 ER-negative cases and 2,745 controls) and European ancestry (1,718 ER-negative cases and 3,670 controls), with replication testing conducted in an additional 2,292 ER-negative cases and 16,901 controls of European ancestry. We identified a common risk variant for ER-negative breast cancer at the TERT-CLPTM1L locus on chromosome 5p15 (rs10069690: per-allele odds ratio (OR) = 1.18 per allele, P = 1.0 × 10(-10)). The variant was also significantly associated with triple-negative (ER-negative, progesterone receptor (PR)-negative and human epidermal growth factor-2 (HER2)-negative) breast cancer (OR = 1.25, P = 1.1 × 10(-9)), particularly in younger women (<50 years of age) (OR = 1.48, P = 1.9 × 10(-9)). Our results identify a genetic locus associated with estrogen receptor negative breast cancer subtypes in multiple populations.