ライフサイエンスコーパス: 3He

1 3He images were successfully and reproducibly generated

2 3He MR imaging may provide a method for evaluating progr

3 3He NMR spectroscopy has been used to study the equilibr

4 3He NMR was used to determine if the products are a mixt

5 3He/4He ratios for MORBs show both positive and negative

6 3He/4He ratios in many ocean-island basalts (OIBs) that

7 The low 238U/3He component may be in the associated depleted refracto

8 ances of the light elements and isotopes 2H, 3He, 4He and 7Li.

9 Although the primordial abundances of 2H, 3He, 4He, and 7Li inferred from current observational da

10 Dynamic hyperpolarized helium 3 (3He) magnetic resonance (MR) imaging of the human airway

11 Two-dimensional helium-3 (3He) provides a simple model for the experimental invest

12 o reservoirs of B-phase superfluid helium-3 (3He-B) were made over a wide range of temperatures.

13 Apatite 4He/3He thermochronometry tightly constrains the timing and

14 independently predicts both the dominant 4He/3He peak found in modern mid-ocean-ridge basalts, as wel

15 lts, as well as estimates of the initial 4He/3He ratio of the Earth.

16 Here I show that the spectrum of 4He/3He ratios in ocean island basalts appears to preserve t

17 This indicates that a 3He-recharged depleted mantle (HRDM) reservoir may be th

18 pact structure contain trapped helium with a 3He/4He ratio of 5.5 x 10(-4) to 5.9 x 10(-4).

19 not for healthy volunteers (P=.35), although 3He and 129Xe VDPs showed a significant correlation for

20 s-adduct, 3, from macrocyclic malonate 1 and 3He@C60 was proven by 3He NMR.

21 We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 ye

22 ography and FAB-MS, as well as IR and 1H and 3He NMR spectroscopies.

23 at 76% and 4He at 24% by mass through 2H and 3He at parts in 105 down to 7Li at parts in 1010.

24 tions of 3-methyl-2-cyclohexenone to C70 and 3He@C70 have been studied by a combination of HPLC chrom

25 y greater (P=.01) than that for FEV1/FVC and 3He VDP (r=-0.84, P<.0001).

26 Together, the D/H and 3He/4He ratios are consistent with conversion in the sun

27 Consequently the 40Ar/36Ar ratios and 3He/36Ar ratios (1.45) determined are minimum estimates

28 Ventilation defect percentages (VDPs) at 3He and 129Xe imaging were obtained by using semiautomat

29 A strong correlation between 3He/4He and 87Sr/86Sr, 143Nd/144Nd and trace element rat

30 ocyclic malonate 1 and 3He@C60 was proven by 3He NMR.

31 We obtained a relatively constant 3He flux over the past 30,000 years.

32 Solutions containing 3He@C60, 129Xe@C60, and varying amounts of 9,10-dimethyl

33 e sun of protosolar deuterium to present-day 3He.

34 e in the flux of interplanetary dust-derived 3He.

35 claim that all low-mass stars should destroy 3He.

36 most solar-mass stars do not produce enough 3He to enrich the interstellar medium significantly.

37 Excess 3He is also present on the same isopycnal between 15°

38 He/4He ratios are due to low 4He, not excess 3He, and do not imply or require a deep or primordial or

39 This finding excludes 3He as a pacemaker of late Pleistocene glacial cycles.

40 ignificant correlation was also observed for 3He and 129Xe ADC (r=0.97, P<.0001); 129Xe ADC was signi

41 t excess "primordial" 3He is responsible for 3He/4He ratios higher than the average for midocean ridg

42 ion coefficients (ADCs) were calculated from 3He (b=1.6 sec/cm2) and 129Xe (b=12 sec/cm2) diffusion-w

43 Laser-polarized gases (3He and 129Xe) are currently being used in magnetic reso

44 ence of neutrons from the reaction D + D --> 3He (820 keV) + n (2.45 MeV) within the target is confir

45 High 3He/4He gases are viewed as products of ancient gas exso

46 High 3He/4He ratios are due to low 4He, not excess 3He, and d

47 High 3He/4He ratios at many ocean islands, along with lower a

48 High 3He/4He ratios found in ocean island basalts are the mai

49 Consequently, high 3He/4He ratios in OIBs are conventionally viewed as evid

50 A depleted source for high 3He/4He ocean island basalts would resolve the apparent

51 mposed on the regional trend are local, high 3He/4He anomalies indicating hidden magmatic activity an

52 eservoir may be the principal source of high 3He/4He in mantle plumes, and may explain why the helium

53 thorium during mantle melting and that high 3He/4He ratios can be preserved in depleted residues of

54 The high 3He/4He ratio of volcanic rocks thought to be derived fr

55 The highest 3He/4He basalts from Hawaii and Iceland plot on the obse

56 rdial abundance of 3He relative to hydrogen: 3He/H = (1.1 +/- 0.2) x 10(-5).

57 VDPs at hyperpolarized 3He and 129Xe imaging were compared with a two-tailed Wi

58 lung periphery, unlike static hyperpolarized 3He MR images on which only the lung periphery is seen.

59 a related but different phenomenon occurs in 3He) may pave the way for a new class of practical rotat

60 Because IDPs are rich in 3He, seafloor sediment 3He concentrations provide a uniq

61 R can alternatively reflect high integrated 3He/(U+Th) ratios or low 4He abundances, as expected in

62 focused on generating a method to introduce 3He into the vascular system.

63 lity that destroys all of the helium isotope 3He produced during the star's lifetime.

64 re efficient at producing the helium isotope 3He, which they mix into the convective envelope on the

65 lower mantle, rich in the primordial isotope 3He.

66 ondensation, and the fermion systems (liquid 3He, the electrons in some metals), which display the re

67 A shallow and low 3He source explains the spatial variability and the temp

68 source) with low 3He concentrations and low 3He/4He ratios.

69 depleted upper mantle (MORB source) with low 3He concentrations and low 3He/4He ratios.

70 in Island, Canada, have the highest magmatic 3He/4He ratios yet recorded.

71 less soluble than xenon in these materials, 3He has been used exclusively for imaging air spaces.

72 Minimum 3He/4He ratios in surface fluids from the northern Basin

73 upper limit for the primordial abundance of 3He relative to hydrogen: 3He/H = (1.1 +/- 0.2) x 10(-5)

74 concile the low observed cosmic abundance of 3He with the predictions of both stellar and Big Bang nu

75 hat some stars produce prodigious amounts of 3He.

76 The evidence however favors depletion of 3He and excessive depletion of 4He and, therefore, favor

77 d heavy-fermion behavior in bilayer films of 3He atoms when adsorbed on the surface of graphite prepl

78 gradient-echo images (resonant frequency of 3He) were obtained to depict lung ventilation.

79 ars poses to the Big Bang nucleosynthesis of 3He.

80 Observations of 3He in planetary nebulae, however, indicate that some st

81 bears analogies with the familiar phases of 3He and 4He (the only known zero-temperature liquids), b

82 However, considering that the signal of 3He is more than 10 times greater than that of 129Xe for

83 solubility issue by producing suspensions of 3He microbubbles.

84 The technique of 3He NMR was used to confirm the selective formation of s

85 The use of 3He NMR was especially powerful in determining the regio

86 ascular images obtained with laser-polarized 3He.

87 After inhalation of the polarized 3He gas, single breath-hold, gradient-echo images (reson

88 ind these models is that excess "primordial" 3He is responsible for 3He/4He ratios higher than the av

89 The ratio 3He/4He (R) plays a central role in models of mantle evo

90 At finer scales, 3He/4He variations along mid-ocean ridges have been rela

91 ause IDPs are rich in 3He, seafloor sediment 3He concentrations provide a unique means of probing the

92 fluid-mineral equilibria, phase separation, 3He/heat ratios and fluxes of volatiles from submarine h

93 roscopic quantum systems (such as superfluid 3He and superconducting UGe2), the superconductivity (or

94 This regime has been detected in superfluid 3He, but was hitherto believed to be unobservable, owing

95 ce experiment involving a liquid: superfluid 3He.

96 was discovered in a weak link of superfluid 3He, which is characterized by a 'p-wave' order paramete

97 Rather, it supports 3He as a constant flux parameter in paleoclimatic studie

98 129Xe VDP was significantly greater than 3He VDP for patients with COPD (P<.0001) but not for hea

99 e first experimental data demonstrating that 3He gas diffusivity in the acinus of human lung is highl

100 rd theory of stellar evolution predicts that 3He is also produced by solar-type stars, so its abundan

101 Thus, we are able to remove the threat that 3He production in low-mass stars poses to the Big Bang n

102 The 3He abundance in star-forming (H II) regions agrees with

103 The 3He bilayer system can be driven toward a quantum critic

104 The 3He/4He ratio exceeds the accepted solar wind value by 2

105 The 3He/4He ratios in the Sudbury fullerenes are similar to

106 ) were allowed to reach equilibrium, and the 3He and 129Xe NMR spectra were taken at the same tempera

107 than in local interstellar hydrogen, and the 3He/4He ratio of (1.1 +/- 0.2) x 10(-4) provides a new v

108 e pattern with periodicity determined by the 3He quantum of circulation.

109 l density of all baryons determined from the 3He data is in excellent agreement with the densities ca

110 e remarkably similar event is present in the 3He record 35 Myr ago, but its origin by comet shower or

111 , with time, generate inhomogeneities in the 3He/4He ratio.

112 ontrol parameter is the total density of the 3He film.

113 Results of the 3He NMR experiments conducted on the product mixture imp

114 nd trace element ratios demonstrate that the 3He-rich end-member is present in basalts that are deriv

115 um plume is strongest near Hawaii, where the 3He/4He ratio at a depth of about 1100 meters reaches va

116 Ventilation and diffusion-weighted 3He MR images were obtained in healthy subjects: 11 smok

117 Through the use of diffusion-weighted 3He MR imaging, Fain et al in this issue of Radiology de

118 of uranium and thorium produces 4He, whereas 3He in the Earth's mantle is not produced by radioactive

119 d a similar and significant correlation with 3He VDP (r=-0.84, P<.0001) and 129Xe VDP (r=-0.89, P<.00

120 rameters at the alveolar level obtained with 3He diffusion MRI in healthy human subjects and patients

121 ing was significantly greater than that with 3He MR imaging, suggesting incomplete or delayed filling