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4.
  • Abe, O, et al. (författare)
  • Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials
  • 2005
  • Ingår i: The Lancet. - 1474-547X. ; 365:9472, s. 1687-1717
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Quinquennial overviews (1985-2000) of the randomised trials in early breast cancer have assessed the 5-year and 10-year effects of various systemic adjuvant therapies on breast cancer recurrence and survival. Here, we report the 10-year and 15-year effects. Methods Collaborative meta-analyses were undertaken of 194 unconfounded randomised trials of adjuvant chemotherapy or hormonal therapy that began by 1995. Many trials involved CMF (cyclophosphamide, methotrexate, fluorouracil), anthracycline-based combinations such as FAC (fluorouracil, doxombicin, cyclophosphamide) or FEC (fluorouracil, epirubicin, cyclophosphamide), tamoxifen, or ovarian suppression: none involved taxanes, trastuzumab, raloxifene, or modem aromatase inhibitors. Findings Allocation to about 6 months of anthracycline-based polychemotherapy (eg, with FAC or FEC) reduces the annual breast cancer death rate by about 38% (SE 5) for women younger than 50 years of age when diagnosed and by about 20% (SE 4) for those of age 50-69 years when diagnosed, largely irrespective of the use of tamoxifen and of oestrogen receptor (ER) status, nodal status, or other tumour characteristics. Such regimens are significantly (2p=0 . 0001 for recurrence, 2p<0 . 00001 for breast cancer mortality) more effective than CMF chemotherapy. Few women of age 70 years or older entered these chemotherapy trials. For ER-positive disease only, allocation to about 5 years of adjuvant tamoxifen reduces the annual breast cancer death rate by 31% (SE 3), largely irrespective of the use of chemotherapy and of age (<50, 50-69, &GE; 70 years), progesterone receptor status, or other tumour characteristics. 5 years is significantly (2p<0 . 00001 for recurrence, 2p=0 . 01 for breast cancer mortality) more effective than just 1-2 years of tamoxifen. For ER-positive tumours, the annual breast cancer mortality rates are similar during years 0-4 and 5-14, as are the proportional reductions in them by 5 years of tamoxifen, so the cumulative reduction in mortality is more than twice as big at 15 years as at 5 years after diagnosis. These results combine six meta-analyses: anthracycline-based versus no chemotherapy (8000 women); CMF-based versus no chemotherapy (14 000); anthracycline-based versus CMF-based chemotherapy (14 000); about 5 years of tamoxifen versus none (15 000); about 1-2 years of tamoxifen versus none (33 000); and about 5 years versus 1-2 years of tamoxifen (18 000). Finally, allocation to ovarian ablation or suppression (8000 women) also significantly reduces breast cancer mortality, but appears to do so only in the absence of other systemic treatments. For middle-aged women with ER-positive disease (the commonest type of breast cancer), the breast cancer mortality rate throughout the next 15 years would be approximately halved by 6 months of anthracycline-based chemotherapy (with a combination such as FAC or FEC) followed by 5 years of adjuvant tamoxifen. For, if mortality reductions of 38% (age <50 years) and 20% (age 50-69 years) from such chemotherapy were followed by a further reduction of 31% from tamoxifen in the risks that remain, the final mortality reductions would be 57% and 45%, respectively (and, the trial results could well have been somewhat stronger if there had been full compliance with the allocated treatments). Overall survival would be comparably improved, since these treatments have relatively small effects on mortality from the aggregate of all other causes. Interpretation Some of the widely practicable adjuvant drug treatments that were being tested in the 1980s, which substantially reduced 5-year recurrence rates (but had somewhat less effect on 5-year mortality rates), also substantially reduce 15-year mortality rates. Further improvements in long-term survival could well be available from newer drugs, or better use of older drugs.
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5.
  • Riley, M A, et al. (författare)
  • Beyond band termination in Er-157 and the search for wobbling excitations in strongly deformed Hf-174
  • 2005
  • Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 31:10, s. 1735-1740
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin terminating bands in heavy nuclei were first identified in nuclei around Er-158(90). While examples of special terminating states have been identified in a number of erbium isotopes, almost nothing is known about the states lying beyond band termination. In the present work the high-spin structure of Er-157 has been studied using the Gammasphere spectrometer. The subject of triaxial superdeformation and 'wobbling' modes in Lu nuclei has rightly attracted a great deal of attention. Very recently, four strongly or superdeformed (SD) sequences have been observed in Hf-174 and ultimate cranker calculations predict, such structures may have significant triaxial deformation. We have performed two experiments in an attempt to verify the possible triaxial nature of these bands. A lifetime measurement was performed to confirm the large (and similar) deformation of the bands. In addition, a high-statistics, thin-target experiment was run to search for linking transitions between the SD bands and possible wobbling modes.
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6.
  • Riley, M. A., et al. (författare)
  • Observation of states beyond band termination in Er-156,Er-157,Er-158 and strongly deformed structures in Hf-173,Hf-174,Hf-175
  • 2006
  • Ingår i: Physica Scripta. - 0031-8949. ; T125, s. 123-126
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin terminating bands in heavy nuclei were first identified in nuclei around Er-158(90). While examples of terminating states have been identified in a number of erbium isotopes, almost nothing is known about the states lying beyond band termination. In the present work, the high-spin structure of Er-156,Er-157,Er-158 has been studied using the Gammasphere spectrometer. The subject of triaxial superdeformation and 'wobbling' modes in Lu nuclei has rightly attracted a great deal of attention. Very recently four strongly or superdeformed (SD) sequences have been observed in Hf-174, and cranking calculations using the Ultimate Cranker code predict that such structures may have significant triaxial deformation. We have performed two experiments in an attempt to verify the possible triaxial nature of these bands. A lifetime measurement was performed to confirm the large (and similar) deformation of the bands. In addition, a high-statistics, thin-target experiment took place to search for linking transitions between the SD bands, possible wobbling modes, and new SD band structures.
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7.
  • Gellanki, Jnaneswari, et al. (författare)
  • Characterization of Superdeformed Bands in 62Zn
  • 2009
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Combined data from four fusion-evaporation reaction experiments were utilized to investigate deformed and superdeformed structures in Zn-62(30)32. Combination of the Gammasphere gamma-ray spectrometer and ancillary particle detection systems allowed for the connection of rotational bands to well-known, low-lying excited states in Zn-62, as well as spectroscopy of discrete high-spin states reaching excitation energies of E-x=42.5 MeV. Four well- or superdeformed bands in Zn-62 are characterized and described by means of cranked Nilsson-Strutinsky calculations.
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8.
  • Riley, M. A., et al. (författare)
  • Strongly Deformed Nuclear Shapes at Ultra-High Spin and Shape Coexistence in N\sim 90 Nuclei
  • 2009
  • Ingår i: Acta Physica Polonica B. - 0587-4254. ; 40:3, s. 513-522
  • Tidskriftsartikel (refereegranskat)abstract
    • The N similar to 90 region of the nuclear chart has featured prominently as the spectroscopy of nuclei at extreme spin has progressed. This talk will present recent discoveries from investigations of high spin behavior in the N similar to 90 Er, Tm and Yb nuclei utilizing the Gammasphere gamma-ray spectrometer. In particular it will include discussion of the beautiful shape evolution and coexistence observed in these nuclei along with the identification of a remarkable new family of band structures. The latter are very weakly populated rotational sequences with high moment of inertia that bypass the classic terminating configurations near spin 40-50 (h) over bar, marking a return to collectivity that extends discrete gamma-ray spectroscopy to well over 60 (h) over bar. Establishing the nature of the yrast states in these nuclei beyond the oblate band-termination states has been a major goal for the past two decades. Cranking calculations suggest that these new structures most likely represent stable triaxial strongly deformed bands that lie in a valley of favored shell energy in deformation and particle-number space.
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9.
  • Valiente-Dobon, JJ, et al. (författare)
  • High-spin rotational structures in Kr-76
  • 2005
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 71:3
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in Kr-76(36)40 have been populated in the Ca-40(Ca-40,4p)Kr-76 fusion-evaporation reaction at abeam energy of 165 MeV and studied using the Gammasphere and Microball multidetector arrays. The ground-state band and two signature-split negative parity bands of Kr-76 have been extended to similar to 30 (h) over bar. Lifetime measurements. using the Doppler-shift attenuation method show that the transition quadrupole moment of these three bands decrease as they approach their maximum-spin states. Two signatures of a new rotational structure with remarkably rigid rotational behavior have been identified. The high-spin properties of these rotational bands are analyzed within the framework of configuration-dependent cranked Nilsson-Strutinsky calculations.
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10.
  • Valiente-Dobon, JJ, et al. (författare)
  • Lifetimes of high-spin states in Kr-76
  • 2005
  • Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 36:4, s. 1339-1342
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in Kr-76(36)40 have been populated in the Ca-40 (Ca-40,4p) Kr-76 fusion-evaporation reaction at a beam energy of 165 MeV, and studied using the GAMMASPHERE and MICROBALL multi-detector arrays. The ground-state band and two signature-split negative-parity bands of Kr-76 have been extended to similar to 30h. Lifetime measurements using the Doppler-shift attenuation method indicate that the transition quadrupole moment of these three bands decrease as they approach their maximum-spin states.
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12.
  • Smith, J. F., et al. (författare)
  • Excited states and signature inversion in Cs-116
  • 2006
  • Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 74:3, s. 034310-
  • Tidskriftsartikel (refereegranskat)abstract
    • Excited states have been observed for the first time in the very neutron-deficient, odd-odd nucleus, Cs-116(55)61. The assignment to Cs-116 has been made by the detection of gamma rays in coincidence with evaporated charged particles and with evaporation residues. The observed states form a rotational band which has been assigned to the nu(h(11/2)) circle times pi(h(11/2)) configuration. Tentative spin assignments have been made on the basis of systematic comparisons with neighboring cesium isotopes. A low-spin signature inversion is observed in the band at a rotational frequency of about 0.23 MeV/h. The observed signature inversions in the odd-odd Cs116-126 isotopes have been compared with the results of extended total Routhian surface calculations, in which signature inversion arises as a consequence of quadrupole-pairing correlations and triaxial deformation. As previously shown for some of the odd-odd A similar or equal to 120 isotopes, the calculations reproduce the signature inversions reasonably well.
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13.
  • Valiente-Dobon, JJ, et al. (författare)
  • Evidence for nontermination of rotational bands in Kr-74
  • 2005
  • Ingår i: Physical Review Letters. - 1079-7114. ; 95:23
  • Tidskriftsartikel (refereegranskat)abstract
    • Three rotational bands in Kr-74 were studied up to (in one case one transition short of) the maximum spin I-max of their respective single-particle configurations. Their lifetimes have been determined using the Doppler-shift attenuation method. The deduced transition quadrupole moments reveal a modest decrease, but far from a complete loss of collectivity at the maximum spin I-max. This feature, together with the results of mean field calculations, indicates that the observed bands do not terminate at I=I-max.
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14.
  • Andersson, Lise-Lotte, et al. (författare)
  • Comprehensive Gamma-ray Spectroscopy of Rotational Bands in the N=Z+1 Nucleus 61Zn
  • 2009
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 79:2
  • Tidskriftsartikel (refereegranskat)abstract
    • The Zn-61(30)31 nucleus has been studied via the combined data of two fusion-evaporation reaction experiments using a Ar-36 beam and a Si-28 target foil. The experimental setups involved the Ge array GAMMASPHERE and neutron and charged particle detectors placed around the target position. The resulting level scheme comprises about 120 excited states connected via some 180 gamma-ray transitions. In total, seven rotational structures were identified up to I similar to 25 or higher and compared with predictions from cranked Nilsson-Strutinsky calculations.
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15.
  • Andersson, Lise-Lotte, et al. (författare)
  • Extensive Gamma-ray Spectroscopy of Normally and Superdeformed Structures in 61Cu
  • 2008
  • Ingår i: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 36:3, s. 251-278
  • Tidskriftsartikel (refereegranskat)abstract
    • A largely extended experimental knowledge of the Cu-61(29)32 nucleus has been obtained from three experiments. Excited states in Cu-61 were produced via the fusion-evaporation reaction Si-28(Ar-36, 3p)Cu-61. In addition to the Ge array GAMMASPHERE, neutron and charged-particle detectors placed around the target position were used for high-performance particle spectroscopy. The constructed level scheme includes more than 160 energy levels and 320 gamma-ray transitions belonging to both normally deformed as well as superdeformed rotational structures. The multipolarities have been determined for the gamma-ray transitions and as a result spin-parity assignments are given for nearly all energy levels. Experimental results in the normally deformed region are compared with predictions from large-scale shell model calculations. The collective structures are compared with results from cranked Nilsson-Strutinsky calculations. The results reveal the need to modify the standard Nilsson parameters in the mass A similar to 60 region.
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16.
  • Campbell, D. B., et al. (författare)
  • Rotational structures and their evolution with spin in Gd-152
  • 2007
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 75:6
  • Tidskriftsartikel (refereegranskat)abstract
    • The fusion-evaporation reaction involving a 175 MeV S-36 beam and a Sn-124 target was performed, and the emitted gamma rays were observed with the Gammasphere spectrometer. Significant additions to the level scheme of Gd-152 were made in spite of the relative weakness of the alpha 4n exit channel, being only similar to 2% of the total fusion cross-section. The high-spin behavior of Gd-152 was compared with that of other N=88 nuclei. A striking similarity was observed with Dy-154 and it is therefore suggested that the angular-momentum-induced shape changes that take place in Dy-154 also occur in Gd-152 in the 30-40h spin range. This is supported by Cranked Nilsson-Strutinsky calculations which were used to interpret the high-spin bands. It is found that a better agreement between calculation and experiment is obtained if the Z=64 shell gap increases with a decreasing number of valence particles outside the doubly-closed Gd-146(64)82 nucleus.
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17.
  • Chiara, C. J., et al. (författare)
  • Probing sd-fp Cross-shell Interactions via Terminating Configurations in 42Sc,43Sc
  • 2007
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 75:5
  • Tidskriftsartikel (refereegranskat)abstract
    • An experimental study of the lower fp-shell nuclei Sc-42,Sc-43 was performed via alpha pn and alpha p evaporation, respectively, from Ne-20 + Si-28 and Mg-24 + Mg-24 fusion-evaporation reactions. The experiments were conducted with the Gammasphere and Microball detector arrays. The level schemes of both nuclei have been extended considerably. Terminating states associated with the f(7/2)(n) and d(3/2)(-1)f(7/2)(n+1) configurations were identified in each nuclide and incorporated into detailed comparisons with neighboring nuclei and with shell model calculations. The energy differences between the terminating states provide a test of the sd-fp cross-shell interactions in these calculations.
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18.
  • Johansson, Emma, et al. (författare)
  • Prompt Proton Decay and Deformed Bands in 56Ni
  • 2008
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 77:6
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in the doubly magic N=Z nucleus Ni-56 have been investigated with three fusion-evaporation reaction experiments. New gamma-ray transitions are added, and a confirmation of a previously suggested prompt proton decay from a rotational band in Ni-56 into the ground state of Co-55 is presented. The rotational bands in Ni-56 are discussed within the framework of cranked Nilsson-Strutinsky calculations.
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19.
  • Johansson, Emma, et al. (författare)
  • Prompt Proton Decay in the Vicinity of 56Ni
  • 2007
  • Ingår i: Proton Emitting Nuclei and Related Topics. - : AIP. - 1551-7616 .- 0094-243X. ; 961, s. 41-46
  • Konferensbidrag (refereegranskat)abstract
    • A new decay mode, the so called prompt proton decay, was discovered in 1998. It has since proven to be an important decay mechanism for several neutron deficient nuclei in the A similar to 60 region. To measure with high accuracy the energies and angular distributions of these protons, a state-of-the-art charged particle detector - LuWuSiA - was developed. It was first utilized during a fusion-evaporation reaction experiment performed at Argonne National Laboratory, U.S.A. In this contribution, the characteristics of the prompt proton decay are discussed along with the special features of LuWuSiA as well as a revisit to the prompt proton decay in Cu-58.
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20.
  • Johansson, Emma, et al. (författare)
  • Thorough Gamma-ray and Particle Decay Investigations of 58Ni
  • 2009
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The combined data from three fusion-evaporation reaction experiments have been utilized to investigate the semi-magic nucleus Ni-58(28)30. To detect gamma rays in coincidence with evaporated particles, the Ge-detector array Gammasphere was used in conjunction with the charged-particle detectors Microball and LuWuSiA (the Lund Washington University Silicon Array), and a neutron detector array. The results yield a significantly extended level scheme of Ni-58 comprising some 340 gamma-ray transitions and include a total of at least 14 discrete particle decays into excited states of the daughter nuclei Fe-54 and Co-57. The level scheme is compared with large-scale shell-model calculations and cranked Nilsson-Strutinsky calculations.
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21.
  • Lawson, J S, et al. (författare)
  • Presence of mouse mammary tumour-like virus gene sequences may be associated with morphology of specific human breast cancer
  • 2006
  • Ingår i: Journal of Clinical Pathology. - : BMJ. - 1472-4146 .- 0021-9746. ; 59:12, s. 1287-1292
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Mouse mammary tumour virus (MMTV) has a proven role in breast carcinogenesis in wild mice and genetically susceptible in-bred mice. MMTV-like env gene sequences, which indicate the presence of a replication-competent MMTV-like virus, have been identified in some human breast cancers, but rarely in normal breast tissues. However, no evidence for a causal role of an MMTV-like virus in human breast cancer has emerged, although there are precedents for associations between specific histological characteristics of human cancers and the presence of oncogenic viruses. AIM: To investigate the possibility of an association between breast cancer and MMTV-like viruses. METHODS: Histological characteristics of invasive ductal human breast cancer specimens were compared with archival MMTV-associated mammary tumours from C3H experimental mice. The presence of MMTV-like env DNA sequences in the human breast cancer specimens was determined by polymerase chain reaction and confirmed by Southern hybridisation. RESULTS: MMTV-like env gene sequences were identified in 22 of 59 (37.3%) human breast cancer specimens. Seventeen of 43 (39.5%) invasive ductal carcinoma breast cancer specimens and 4 of 16 (25%) ductal carcinoma in situ specimens had some histological characteristics, which were similar to MMTV-associated mouse mammary tumours. However, these similarities were not associated with the presence or absence of MMTV-like gene sequences in the human breast tumour specimens. A significant (p = 0.05) correlation was found between the grade of the human breast cancer and similarity to the mouse mammary tumours. The lower the grade, the greater the similarity. CONCLUSION: Some human breast cancer specimens, in which MMTV-like env DNA sequences have been identified, were shown to have histological characteristics (morphology) similar to MMTV-associated mouse mammary tumours. These observations are compatible with, but not conclusive of, an association between the presence of MMTV-like env DNA sequences and some human breast cancers.
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22.
  • Torres, D. A., et al. (författare)
  • Deformations and Magnetic Rotations in the 60Ni Nucleus
  • 2008
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Data from three experiments using the heavy-ion fusion evaporation-reaction Ar-36+Si-28 have been combined to study high-spin states in the residual nucleus Ni-60, which is populated via the evaporation of four protons from the compound nucleus Ge-64. The GAMMASPHERE array was used for all the experiments in conjunction with a 4 pi charged-particle detector arrays (MICROBALL, LUWUSIA) and neutron detectors (NEUTRON SHELL) to allow for the detection of. rays in coincidence with the evaporated particles. An extended Ni-60 level scheme is presented, comprising more than 270 gamma-ray transitions and 110 excited states. Their spins and parities have been assigned via directional correlations of gamma rays emitted from oriented states. Spherical shell-model calculations in the fp-shell characterize some of the low-spin states, while the experimental results of the rotational bands are analyzed with configuration-dependent cranked Nilsson-Strutinsky calculations.
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23.
  • du Rietz, Rickard, et al. (författare)
  • Investigation of High-spin States in 53Fe
  • 2005
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 72:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The fusion-evaporation reactions Si-28(S-32,1 alpha 2p1n)Fe-53 at 125 MeV and Mg-24(S-32,2p1n)Fe-53 at a 95-MeV beam energy were used to investigate excited states in Fe-53. The combination of the Gammasphere Ge detector array and ancillary devices led to the construction of an extensive level scheme comprising some 90 transitions connecting 40 states. The lifetime of the yrast 25/2(-) state and upper limits for the lifetimes of a number of additional states were determined using the Cologne plunger device coupled to the GASP gamma-ray spectrometer. The experimental results are compared to large-scale shell-model calculations using different sets of two-body matrix elements. In particular, predictions on electromagnetic decay properties such as lifetimes, branching ratios, and mixing ratios are studied in detail.
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24.
  • Teal, C., et al. (författare)
  • Triaxial strongly deformed bands in Tm-160,Tm-161
  • 2008
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:1
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in Tm-160,Tm-161 were populated using the Te-128(Cl-37, 5n and 4n) reactions at a beam energy of 170 MeV. Emitted gamma rays were detected in the Gammasphere spectrometer. Two rotational bands with high moments of inertia were discovered, one assigned to Tm-160, while the other tentatively assigned to Tm-161. These sequences display features similar to bands observed in neighboring Er, Tm, Yb, and Lu nuclei which have been discussed in terms of triaxial strongly deformed structures. Cranked Nilsson Strutinsky calculations have been performed that predict well-deformed triaxial shapes at high spin in Tm-160,Tm-161.
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25.
  • Bentley, M. A., et al. (författare)
  • Isospin symmetry of odd-odd mirror nuclei: Identification of excited states in N=Z-2 Mn-48
  • 2006
  • Ingår i: Physical Review Letters. - 1079-7114. ; 97:13: 132501
  • Tidskriftsartikel (refereegranskat)abstract
    • Excited states have been observed in the N=Z-2 odd-odd nucleus Mn-48 for the first time. Through comparison with the structure of V-48, a first high-spin study of an odd-odd mirror pair has been achieved. Differences between the T=1 analogue states in this pair have been interpreted in terms of Coulomb effects, with the aid of shell-model calculations in the full pf valence space. Unlike other mirror pairs, the energy differences have been interpreted almost entirely as due to a monopole effect associated with smooth changes in radius (or deformation) as a function of angular momentum. In addition, the large energy shift between analogue negative-parity states is interpreted in terms of the electromagnetic spin-orbit interaction in nuclei.
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26.
  • Brose, Ulrich, et al. (författare)
  • Body sizes of consumers and their resources
  • 2005
  • Ingår i: Ecology. - : Ecological Society of America. - 0012-9658 .- 1939-9170. ; 86:9, s. 2545-2545
  • Tidskriftsartikel (refereegranskat)abstract
    • Trophic information—who eats whom—and species’ body sizes are two of the most basic descriptions necessary to understand community structure as well as ecological and evolutionary dynamics. Consumer–resource body size ratios between predators and their prey, and parasitoids and their hosts, have recently gained increasing attention due to their important implications for species’ interaction strengths and dynamical population stability. This data set documents body sizes of consumers and their resources. We gathered body size data for the food webs of Skipwith Pond, a parasitoid community of grass-feeding chalcid wasps in British grasslands; the pelagic community of the Benguela system, a source web based on broom in the United Kingdom; Broadstone Stream, UK; the Grand Caric¸aie marsh at Lake Neuchaˆtel, Switzerland; Tuesday Lake, USA; alpine lakes in the Sierra Nevada of California; Mill Stream, UK; and the eastern Weddell Sea Shelf, Antarctica. Further consumer–resource body size data are included for planktonic predators, predatory nematodes, parasitoids, marine fish predators, freshwater invertebrates, Australian terrestrial consumers, and aphid parasitoids. Containing 16 807 records, this is the largest data set ever compiled for body sizes of consumers and their resources. In addition to body sizes, the data set includes information on consumer and resource taxonomy, the geographic location of the study, the habitat studied, the type of the feeding interaction (e.g., predacious, parasitic) and the metabolic categories of the species (e.g., invertebrate, ectotherm vertebrate). The present data set was gathered with the intent to stimulate research on effects of consumer–resource body size patterns on food-web structure, interaction-strength distributions, population dynamics, and community stability. The use of a common data set may facilitate cross-study comparisons and understanding of the relationships between different scientific approaches and models.
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27.
  • Carpenter, D, et al. (författare)
  • Genetics of susceptibility to malaria related phenotypes
  • 2009
  • Ingår i: Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases. - : Elsevier BV. - 1567-1348. ; 9:1, s. 97-103
  • Tidskriftsartikel (refereegranskat)
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28.
  • Chapin, III F.S., et al. (författare)
  • Resilience-based stewardship : Strategies for navigating sustainable pathways in a changing world.
  • 2009
  • Ingår i: Principles of ecosystem stewardship. - New York : Springer Verlag. - 9780387730332 ; , s. 319-337
  • Bokkapitel (populärvet., debatt m.m.)abstract
    • Accelerated global changes in climate, environment, and social–ecological systems demand a transformation in human perceptions of our place in nature and patterns of resource use. The biology and culture of Homo sapiens evolved for about 95% of our species’ history in hunting-and-gathering societies before the emergence of settled agriculture. We have lived in complex societies for about 3%, and in industrial societies using fossil fuels for about 0.1% of our history. The pace of cultural evolution, including governance arrangements and resource-use patterns, appears insufficient to adjust to the rate and magnitude of technological innovations, human population increases, and environmental impacts that have occurred. Many of these changes are accelerating, causing unsustainable exploitation of ecosystems, including many boreal and tropical forests, drylands, and marine fisheries. The net effect has been serious degradation of the planet’s life-support system on which societal development ultimately depends (see Chapters 2 and 14.
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29.
  • Hartley, D. J., et al. (författare)
  • Wobbling mode in Ta-167
  • 2009
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:4
  • Tidskriftsartikel (refereegranskat)abstract
    • The collective wobbling mode, the strongest signature for the rotation of a triaxial nucleus, has previously been seen only in a few Lu isotopes in spite of extensive searches in nearby isotopes. A sequence of transitions in the N = 94 Ta-167 nucleus exhibiting features similar to those attributed to the wobbling bands in the Lu nuclei has now been found. This band feeds into the pi i(13/2) band at a relative energy similar to that seen in the established wobbling bands and its dynamic moment of inertia and alignment properties are nearly identical to the i(13/2) structure over a significant frequency range. Given these characteristics, it is likely that the wobbling mode has been observed for the first time in a nucleus other than Lu, making this collective motion a more general phenomenon.
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30.
  • Johansson, Emma, et al. (författare)
  • Gamma-ray Spectroscopy of the Doubly Magic Nucleus 56Ni
  • 2006
  • Ingår i: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001. ; 27:2, s. 157-165
  • Tidskriftsartikel (refereegranskat)abstract
    • The doubly magic N = Z nucleus Ni-56 has been investigated with two fusion-evaporation reactions; Ca-40(Si-28, 3 alpha)Ni-56 at a beam energy of 122MeV and Si-28(S-32, 2p2n)Ni-56 at 130MeV. To detect gamma-rays in coincidence with evaporated particles the Ge-detector array Gammasphere was used in conjunction with the charged-particle detector system, Microball and a 1 pi neutron detector array. Results include a significantly extended level scheme of Ni-56, which is compared to large-scale shell model calculations in the fp shell. The experimental and theoretical results agree to a large extent, with one notable exception; the theoretical model fails to predict the proper sequence of the yrast and yrare 8(+) states.
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31.
  • Ollier, J., et al. (författare)
  • Ultrahigh-spin spectroscopy of Er-159,Er-160: Observation of triaxial strongly deformed structures
  • 2009
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 80:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Three weakly populated high-spin rotational bands associated with the gamma decay of Er-159 and Er-160 were observed in fusion-evaporation reactions involving a beam of Ca-48 at an energy of 215 MeV incident on a Cd-116 target. The gamma decays were detected using the highly efficient Gammasphere spectrometer. The discovery of these bands, which extend discrete-line spectroscopy in these nuclei to ultrahigh spin of similar to 60h, is consistent with recent observations of high-spin collective structures in isotopes of Er, Yb, and Tm around N=90. Cranked Nilsson-Strutinsky calculations suggest that these bands may arise from well-deformed triaxial configurations with either positive or negative gamma deformation.
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32.
  • Rudolph, Dirk, et al. (författare)
  • 58Ni: An Unpaired Band Crossing at New Heights of Angular Momentum for Rotating Nuclei
  • 2006
  • Ingår i: Physical Review Letters. - 1079-7114. ; 96:9
  • Tidskriftsartikel (refereegranskat)abstract
    • High-spin states in Ni-58 have been investigated by means of the fusion-evaporation reaction Si-28(S-32,2p)Ni-58 at 130 MeV beam energy. Discrete-energy levels are observed in Ni-58 at record-breaking 42 MeV excitation energy and angular momenta in excess of 30h. The states form regular rotational bands with unprecedented high rotational frequencies. A comparison with configuration dependent cranked Nilsson-Strutinsky calculations reveals an exceptional two-band crossing scenario, the interaction strength of which is strongly shape dependent.
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33.
  • Tokuno, Craig D, et al. (författare)
  • Control of the triceps surae during the postural sway of quiet standing.
  • 2007
  • Ingår i: Acta Physiologica. - : Wiley. - 1748-1708 .- 1748-1716. ; 191:3, s. 229-36
  • Tidskriftsartikel (refereegranskat)abstract
    • AIM: The present study investigated how the triceps surae are controlled at the spinal level during the naturally occurring postural sway of quiet standing. METHODS: Subjects stood on a force platform as electrical stimuli were applied to the posterior tibial nerve when the center of pressure (COP) was either 1.6 standard deviations anterior (COP(ant)) or posterior (COP(post)) to the mean baseline COP signal. Peak-to-peak amplitudes of the H-reflex and M-wave from the soleus (SOL) and medial gastrocnemius (MG) muscles were recorded to assess the efficacy of the Ia pathway. RESULTS: A significant increase in the H(max) : M(max) ratio for both the SOL (12 +/- 6%) and MG (23 +/- 6%) was observed during the COP(ant) as compared to the COP(post) condition. The source of the modulation between COP conditions cannot be determined from this study. However, the observed changes in the synaptic efficacy of the Ia pathway are unlikely to be simply a result of an altered level of background electromyographic activity in the triceps surae. This was indicated by the lack of differences observed in the H(max) : M(max) ratio when subjects stood without postural sway (via the use of a tilt table) at two levels of background activity. CONCLUSIONS: It is suggested that the phase-dependent modulation of the triceps surae H-reflexes during the postural sway of quiet standing functions to maintain upright stance and may explain the results from previous studies, which, until now, had not taken the influence of postural sway on the H-reflex into consideration.
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34.
  • Tokuno, Craig D, et al. (författare)
  • Sway-dependent modulation of the triceps surae H-reflex during standing.
  • 2008
  • Ingår i: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 104:5, s. 1359-65
  • Tidskriftsartikel (refereegranskat)abstract
    • Previous research has shown that changes in spinal excitability occur during the postural sway of quiet standing. In the present study, it was of interest to examine the independent effects of sway position and sway direction on the efficacy of the triceps surae Ia pathway, as reflected by the Hoffman (H)-reflex amplitude, during standing. Eighteen participants, tested under two different experimental protocols, stood quietly on a force platform. Percutaneous electrical stimulation was applied to the posterior tibial nerve when the position and direction of anteroposterior (A-P) center of pressure (COP) signal satisfied the criteria for the various experimental conditions. It was found that, regardless of sway position, a larger amplitude of the triceps surae H-reflex (difference of 9-14%; P = 0.005) occurred when subjects were swaying in the forward compared with the backward direction. The effects of sway position, independent of the sway direction, on spinal excitability exhibited a trend (P = 0.075), with an 8.9 +/- 3.7% increase in the H-reflex amplitude occurring when subjects were in a more forward position. The observed changes to the efficacy of the Ia pathway cannot be attributed to changes in stimulus intensity, as indicated by a constant M-wave amplitude, or to the small changes in the level of background electromyographic activity. One explanation for the changes in reflex excitability with respect to the postural sway of standing is that the neural modulation may be related to the small lengthening and shortening contractions occurring in the muscles of the triceps surae.
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35.
  • Tokuno, Craig D, et al. (författare)
  • The influence of natural body sway on neuromuscular responses to an unpredictable surface translation.
  • 2006
  • Ingår i: Experimental Brain Research. - : Springer Science and Business Media LLC. - 0014-4819 .- 1432-1106. ; 174:1, s. 19-28
  • Tidskriftsartikel (refereegranskat)abstract
    • Previous research has shown that the postural configuration adopted by a subject, such as active leaning, influences the postural response to an unpredictable support surface translation. While those studies have examined large differences in postural conditions, it is of additional interest to examine the effects of naturally occurring changes in standing posture. Thus, it was hypothesized that the normal postural sway observed during quiet standing would affect the responses to an unpredictable support surface translation. Seventeen young adults stood quietly on a moveable platform and were perturbed in either the forward or backward direction when the location of the center of pressure (COP) was either 1.5 standard deviations anterior or posterior to the mean baseline COP signal. Postural responses, in the form of electromyographic (EMG) latencies and amplitudes, were recorded from lower limb and trunk muscles. When the location of the COP at the time of the translation was in the opposite, as compared to the same, direction as the upcoming translation, there was a significantly earlier onset of the antagonists (10-23%, i.e. 15-45 ms) and a greater EMG amplitude (14-39%) in four of the six recorded muscles. Stepping responses were most frequently observed during trials where the position of the COP was opposite to the direction of the translation. The results support the hypothesis that postural responses to unpredictable support surface translations are influenced by the normal movements of postural sway. The results may help to explain the large variability of postural responses found between past studies.
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36.
  • Yadav, R. B., et al. (författare)
  • Identification of triaxial strongly deformed bands in Hf-168
  • 2008
  • Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 78:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Possible decay pathways associated with three candidates for triaxial strongly deformed (TSD) bands in Hf-168 have been investigated. The spin and excitation energy of the strongest band, TSD1, were determined approximately based on gamma-ray coincidence relationships. Discrete links were established for the second band. The overall agreement between the observed properties of the bands and cranking calculations using the ULTIMATE CRANKER code provides strong support for an interpretation where band TSD1 is associated with a TSD minimum, (epsilon(2),gamma)similar to(0.43,20(degrees)), involving the pi(i(13/2))(2) and the nu(j(15/2)) high-j orbitals. This constitutes the first identification of a TSD band in Hf isotopes, which has been long-predicted by theoretical studies. The second band is understood as being associated with a near-prolate shape and a deformation enhanced with respect to the normal deformed bands. It is proposed to be built on the pi(i(13/2)h(9/2))circle times nu(i(13/2))(2) configuration.
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