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Showing papers by "Tohoku University published in 2006"


Journal ArticleDOI
TL;DR: Ovarian-type stroma has been proposed as a requisite to distinguish MCN from IPMN, and some other distinct features to characterize IPMN and MCN have been identified, but there remain ambiguities between the two diseases.

1,912 citations


Journal ArticleDOI
23 Feb 2006-Nature
TL;DR: The magnetic-field-induced shape recovery of a compressively deformed NiCoMnIn alloy is reported, attributing this deformation behaviour to a reverse transformation from the antiferromagnetic (or paramagnetic) martensitic to the ferromagnetic parent phase in the Ni45Co5Mn36.7In13.3 single crystal.
Abstract: Large magnetic-field-induced strains1 have been observed in Heusler alloys with a body-centred cubic ordered structure and have been explained by the rearrangement of martensite structural variants due to an external magnetic field1,2,3. These materials have attracted considerable attention as potential magnetic actuator materials. Here we report the magnetic-field-induced shape recovery of a compressively deformed NiCoMnIn alloy. Stresses of over 100 MPa are generated in the material on the application of a magnetic field of 70 kOe; such stress levels are approximately 50 times larger than that generated in a previous ferromagnetic shape-memory alloy4. We observed 3 per cent deformation and almost full recovery of the original shape of the alloy. We attribute this deformation behaviour to a reverse transformation from the antiferromagnetic (or paramagnetic) martensitic to the ferromagnetic parent phase at 298 K in the Ni45Co5Mn36.7In13.3 single crystal.

1,581 citations


Journal ArticleDOI
TL;DR: A better understanding of the ubiquitylation machinery will provide new insights into the regulatory biology of cell-cycle transitions and the development of anti-cancer drugs.
Abstract: A driving force of the cell cycle is the activation of cyclin-dependent kinases (CDKs), the activities of which are controlled by the ubiquitin-mediated proteolysis of key regulators such as cyclins and CDK inhibitors. Two ubiquitin ligases, the SKP1-CUL1-F-box-protein (SCF) complex and the anaphase-promoting complex/cyclosome (APC/C), are responsible for the specific ubiquitylation of many of these regulators. Deregulation of the proteolytic system might result in uncontrolled proliferation, genomic instability and cancer. Cumulative clinical evidence shows alterations in the ubiquitylation of cell-cycle regulators in the aetiology of many human malignancies. A better understanding of the ubiquitylation machinery will provide new insights into the regulatory biology of cell-cycle transitions and the development of anti-cancer drugs.

1,365 citations


Journal ArticleDOI
23 Mar 2006-Nature
TL;DR: An anatomical difference in the distribution in the human airway of the different binding molecules preferred by the avian and human influenza viruses is demonstrated to provide a rational explanation for why H5N1 viruses at present rarely infect and spread between humans although they can replicate efficiently in the lungs.
Abstract: Avian and human flu viruses seem to target different regions of a patient's respiratory tract.

1,312 citations


Journal ArticleDOI
TL;DR: The LPI-ARTICLE-2006-008doi:10.1002/adma.200502540View record in Web of Science Record created on 2006-05-03, modified on 2016-08-08 as discussed by the authors.
Abstract: Reference LPI-ARTICLE-2006-008doi:10.1002/adma.200502540View record in Web of Science Record created on 2006-05-03, modified on 2016-08-08

1,001 citations


Journal ArticleDOI
TL;DR: In this article, the isotopic abundances of atmospheric Ar were determined using a dynamically operated isotope ratio mass spectrometer with minor modifications and special gas handling techniques to avoid fractionation.

908 citations


Journal ArticleDOI
07 Apr 2006-Science
TL;DR: Cobalt-base superalloys showing a high-temperature strength greater than those of conventional nickel-basesuperalloys are identified and structures offering great promise as candidates for next-generation high-Temperature materials are identified.
Abstract: We have identified cobalt-base superalloys showing a high-temperature strength greater than those of conventional nickel-base superalloys. The cobalt-base alloys are strengthened by a ternary compound with the L1 2 structure, \({\gamma}^{{^\prime}}\) Co 3 (Al,W), which precipitates in the disordered γ face-centered cubic cobalt matrix with high coherency and with high melting points. We also identified a ternary compound, \({\gamma}^{{^\prime}}\) Ir 3 (Al,W), with the L1 2 structure, which suggests that the Co-Ir-Al-W–base systems with \({\gamma}+{\gamma}^{{^\prime}}\) (Co,Ir) 3 (Al,W) structures offer great promise as candidates for next-generation high-temperature materials.

867 citations


Journal ArticleDOI
TL;DR: Treatment with a low dose of pravastatin reduces the risk of coronary heart disease in Japan by much the same amount as higher doses have shown in Europe and the USA.

858 citations


Journal ArticleDOI
13 Sep 2006-JAMA
TL;DR: Green tea consumption is associated with reduced mortality due to all causes and due to cardiovascular disease but not with reduced Mortality due to cancer.
Abstract: associated with different green tea consumption frequencies were 1.00 (reference) for less than 1 cup/d, 0.93 (95% confidence interval [CI], 0.83-1.05) for 1 to 2 cups/d, 0.95 (95% CI, 0.85-1.06) for 3 to 4 cups/d, and 0.88 (95% CI, 0.79-0.98) for 5 or more cups/d, respectively (P=.03 for trend). The corresponding data for women were 1.00, 0.98 (95% CI, 0.84-1.15), 0.82 (95% CI, 0.70-0.95), and 0.77 (95% CI, 0.67-0.89), respectively (P.001 for trend). The inverse association with cardiovascular disease mortality was stronger than that with all-cause mortality. This inverse association was also stronger in women (P=.08 for interaction with sex). In women, the multivariate hazard ratios of cardiovascular disease mortality across increasing green tea consumption categories were 1.00, 0.84 (95% CI, 0.63-1.12), 0.69 (95% CI, 0.52-0.93), and 0.69 (95% CI, 0.53-0.90), respectively (P=.004 for trend). Among the types of cardiovascular disease mortality, the strongest inverse association was observed for stroke mortality. In contrast, the hazard ratios of cancer mortality were not significantly different from 1.00 in all green tea categories compared with the lowest-consumption category.

725 citations


Journal ArticleDOI
M. H. Ahn1, E. Aliu2, S. Andringa2, Shigeki Aoki3  +217 moreInstitutions (29)
TL;DR: In this article, measurements of {nu}{sub {mu}} disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment are presented.
Abstract: We present measurements of {nu}{sub {mu}} disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One-hundred and twelve beam-originated neutrino events are observed in the fiducial volume of Super-Kamiokande with an expectation of 158.1{sub -8.6}{sup +9.2} events without oscillation. A distortion of the energy spectrum is also seen in 58 single-ring muonlike events with reconstructed energies. The probability that the observations are explained by the expectation for no neutrino oscillation is 0.0015% (4.3{sigma}). In a two-flavor oscillation scenario, the allowed {delta}m{sup 2} region at sin{sup 2}2{theta}=1 is between 1.9 and 3.5x10{sup -3} eV{sup 2} at the 90% C.L. with a best-fit value of 2.8x10{sup -3} eV{sup 2}.

672 citations


Journal ArticleDOI
01 Nov 2006-Immunity
TL;DR: It is demonstrated that Tyk2 plays obligatory roles in multiple cytokine signals involved in innate and acquired immunity of humans, which differs substantially fromTyk2 function in mice.

Journal ArticleDOI
01 Jun 2006-Nature
TL;DR: It is shown that sea surface temperatures near the North Pole increased from ∼18 °C to over 23‬°C during this event, which suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms—perhaps polar stratospheric clouds or hurricane-induced ocean mixing—to amplify early Palaeogene polar temperatures.
Abstract: The Palaeocene/Eocene thermal maximum, ~55 million years ago, was a brief period of widespread, extreme climatic warming1, 2, 3, that was associated with massive atmospheric greenhouse gas input4. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition5. We show that sea surface temperatures near the North Pole increased from ~18 °C to over 23 °C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations6, but the absolute polar temperatures that we derive before, during and after the event are more than 10 °C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms—perhaps polar stratospheric clouds7 or hurricane-induced ocean mixing8—to amplify early Palaeogene polar temperatures.

Journal ArticleDOI
TL;DR: The morphology and crystallography of lath martensite in two Mn-containing interstitial free steels and a maraging steel were examined in detail by a combination of transmission electron microscopy, electron backscatter diffraction in a scanning electron microscope and optical microscopy.

Journal ArticleDOI
TL;DR: Ferroelectric transition has been detected in a ferrimagnetic spinel oxide of CoCr2O4 upon the transition to the conical spin order below 25 K, indicating the clamping of the ferromagnetic and ferroelectric domain walls.
Abstract: Ferroelectric transition has been detected in a ferrimagnetic spinel oxide of CoCr2O4 upon the transition to the conical spin order below 25 K. The direction [110] of the spontaneous polarization is normal to both the magnetization easy axis [001] and to the propagation axis [110] of the transverse spiral component, in accord with the prediction based on the spin-current model. The reversal of the spontaneous magnetization by a small magnetic field (approximately 0.1 T) induces the reversal of the spontaneous polarization, indicating the clamping of the ferromagnetic and ferroelectric domain walls.

Journal ArticleDOI
TL;DR: Dysregulation of the RAS-RAF-ERK pathway is a common molecular basis for the three related disorders of Cardio-facio-cutaneous syndrome, which phenotypically overlaps with Noonan and Costello syndrome.
Abstract: Cardio-facio-cutaneous (CFC) syndrome is characterized by a distinctive facial appearance, heart defects and mental retardation. It phenotypically overlaps with Noonan and Costello syndrome, which are caused by mutations in PTPN11 and HRAS, respectively. In 43 individuals with CFC, we identified two heterozygous KRAS mutations in three individuals and eight BRAF mutations in 16 individuals, suggesting that dysregulation of the RAS-RAF-ERK pathway is a common molecular basis for the three related disorders.

Journal ArticleDOI
TL;DR: The accumulation of many AIP cases shows that the concept of AIP has changed slightly to include extrapancreatic lesions and associated disorders, which suggests that the current diagnostic criteria are becoming inadequate.
Abstract: In 1961, Sarles et al.1 asked the following question regarding the particular cases of pancreatitis with hypergammaglobulinemia: “Chronic inflammatory sclerosis of the pancreas—an autoimmune pancreatic disease?” As similar cases were rarely observed, a relationship between such pancreatitis and autoimmunity was viewed skeptically during the following several decades. In 1992, Toki et al.2 have reported 4 cases with unusual diffuse irregular narrowing of the main pancreatic duct and diffuse enlargement of the entire pancreas due to lymphocyte infiltration. In 1995, Japanese investigators3 firstly proposed a concept of “autoimmune pancreatitis (AIP)”, in which the patients showed diffusely enlarged pancreas, narrowing pancreatogram, increased serum IgG, presence of autoantibodies, fibrotic changes with lymphocytic infiltration and steroidal efficacy. Thereafter, many AIP cases have been reported from Japan, and AIP has been accepted as a new clinical entity.4,5 The histopathological findings of AIP show massive infiltration of lymphoplasmacytes with fibrosis, which is consistent with lymphoplasmacytic sclerosing pancreatitis (LPSP).6 Many Japanese investigators have paid great attention to AIP, especially with regard to its unique pancreatic images,2 IgG4,7 disease-associated autoantibodies,8 extrapancreatic lesions,6,9–14 and steroidal efficacy.14,15 Currently in Japan, diagnosis of AIP is based on the “diagnostic criteria 2002 of autoimmune pancreatitis”16 proposed by the Japan Pancreas Society. However, the accumulation of many AIP cases shows that the concept of AIP has changed slightly to include extrapancreatic lesions and associated disorders, which suggests that the current diagnostic criteria are becoming inadequate. In 2003, the Research Committee of Intractable Diseases of the Pancreas, supported by the Japanese Ministry of Health, Labour and Welfare (Chairman, M. Otsuki), began to review the current diagnostic criteria in light of recently acquired information and knowledge. The team organized a working group (WG), consisting of the team members and researchers specializing in autoimmune pancreatitis, to develop a proposal for the revision of the current diagnostic criteria. On 7 October 2005 and 22 April 2006, the Research Committee of Intractable Diseases of the Pancreas and the Japan Pancreas Society jointly held open forums to discuss the proposed amendments. This report describes the background of the proposed amendments and the final proposal for the revised version of the clinical diagnostic criteria of AIP.

Journal ArticleDOI
TL;DR: Treatment with gefitinib alone for chemotherapy-naïve NSCLC patients with EGFR mutations could achieve a high efficacy with acceptable toxicity, and a subsequent randomized trial comparing gefITinib with standard chemotherapy is warranted.
Abstract: Purpose This study was undertaken to investigate the efficacy and the feasibility of gefitinib for chemotherapy-naive patients with advanced non–small-cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. Patients and Methods The EGFR gene status in various tumor samples obtained from chemotherapy-naive advanced NSCLC patients was examined by DNA sequencing of EGFR exons 18 to 23. Patients harboring EGFR mutations received gefitinib (250 mg/d) alone. The response rate, progression-free survival (PFS), and toxicity profile were assessed prospectively. Results Between June 2004 and October 2005, 75 patients were examined for the EGFR status, and 25 patients (33%) harbored EGFR mutations. EGFR mutations were significantly frequent in females (P < .01) and never or light smokers (P < .001). Sixteen patients with EGFR mutations were enrolled onto the study. The overall response rate in these patients was 75% (95% CI, 54% to 96%), and the disease control rate was 88% (95% CI, 71%...

Journal ArticleDOI
01 Jun 2006-Nature
TL;DR: This record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice and East Antarctic ice and supporting arguments for bipolar symmetry in climate change.
Abstract: The history of the Arctic Ocean during the Cenozoic era (0–65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from >400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a palaeoenvironmental transition from a warm ‘greenhouse’ world, during the late Palaeocene and early Eocene epochs, to a colder ‘icehouse’ world influenced by sea ice and icebergs from the middle Eocene epoch to the present. For the most recent ~14 Myr, we find sedimentation rates of 1–2 cm per thousand years, in stark contrast to the substantially lower rates proposed in earlier studies; this record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice (~3.2 Myr ago) and East Antarctic ice (~14 Myr ago). We find evidence for the first occurrence of ice-rafted debris in the middle Eocene epoch (~45 Myr ago), some 35 Myr earlier than previously thought; fresh surface waters were present at ~49 Myr ago, before the onset of ice-rafted debris. Also, the temperatures of surface waters during the Palaeocene/Eocene thermal maximum (~55 Myr ago) appear to have been substantially warmer than previously estimated. The revised timing of the earliest Arctic cooling events coincides with those from Antarctica, supporting arguments for bipolar symmetry in climate change.

Journal ArticleDOI
TL;DR: In this article, an extensive search for Lyα emitters (LAEs) at z = 6.5 in the Subaru Deep Field was conducted, which revealed an apparent deficit at the bright end of ∼ 0.75 mag fainter L*, compared with that observed at z=5.7.
Abstract: We report an extensive search for Lyα emitters (LAEs) at z = 6.5 in the Subaru Deep Field. Subsequent spectroscopy with Subaru and Keck identified eight more LAEs, giving a total of 17 spectroscopically confirmed LAEs at z = 6.5. Based on this spectroscopic sample of 17, complemented by a photometric sample of 58 LAEs, we have derived a more accurate Lyα luminosity function of LAEs at z = 6.5, which reveals an apparent deficit at the bright end of ∼0.75 mag fainter L*, compared with that observed at z = 5.7. The difference in the LAE luminosity functions between z = 5.7 and 6.5 is significant at the 3 σ level, which is reduced to 2 σ when cosmic variance is taken into account. This result may imply that the reionization of the universe has not been completed at z = 6.5. We found that the spatial distribution of LAEs at z = 6.5 was homogeneous over the field. We discuss the implications of these results for the reionization of the universe. © 2006. The American Astronomical Society. All rights reserved.

Journal ArticleDOI
TL;DR: The p16INK4a /Rb-pathway also cooperates with mitogenic signals to induce elevated intracellular levels of reactive oxygen species (ROS), thereby activating protein kinase Cδ (PKCδ) in human senescent cells, uncover an unexpected role for the p16ink4a–Rb pathway and provide a new insight into how senescent cell-cycle arrest is enforced in human cells.
Abstract: The p16(INK4a) cyclin-dependent kinase inhibitor has a key role in establishing stable G1 cell-cycle arrest through activating the retinoblastoma (Rb) tumour suppressor protein pRb in cellular senescence. Here, we show that the p16(INK4a) /Rb-pathway also cooperates with mitogenic signals to induce elevated intracellular levels of reactive oxygen species (ROS), thereby activating protein kinase Cdelta (PKCdelta) in human senescent cells. Importantly, once activated by ROS, PKCdelta promotes further generation of ROS, thus establishing a positive feedback loop to sustain ROS-PKCdelta signalling. Sustained activation of ROS-PKCdelta signalling irreversibly blocks cytokinesis, at least partly through reducing the level of WARTS (also known as LATS1), a mitotic exit network (MEN) kinase required for cytokinesis, in human senescent cells. This irreversible cytokinetic block is likely to act as a second barrier to cellular immortalization ensuring stable cell-cycle arrest in human senescent cells. These results uncover an unexpected role for the p16(INK4a)-Rb pathway and provide a new insight into how senescent cell-cycle arrest is enforced in human cells.

Journal ArticleDOI
TL;DR: In this article, the authors presented a method to detect the presence of a tumor in the human brain using the PhysRevB database, which was created on 2015-03-03, modified on 2017-05-12.
Abstract: Note: Times Cited: 251 Reference EPFL-ARTICLE-206012doi:10.1103/PhysRevB.74.045126View record in Web of Science URL: ://WOS:000239426800043 Record created on 2015-03-03, modified on 2017-05-12

Journal ArticleDOI
J. P. Cravens1, K. Abe2, T. Iida2, K. Ishihara2  +147 moreInstitutions (34)
TL;DR: The results of the second phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first phase in this paper, showing no evidence of systematic tendencies between the first and second phases.
Abstract: The results of the second phase of the Super-Kamiokande solar neutrino measurement are presented and compared to the first phase. The solar neutrino flux spectrum and time variation as well as oscillation results are statistically consistent with the first phase and do not show spectral distortion. The time-dependent flux measurement of the combined first and second phases coincides with the full period of solar cycle 23 and shows no correlation with solar activity. The measured {sup 8}B total flux is (2.38{+-}0.05(stat.){sub -0.15}{sup +0.16}(sys.))x10{sup 6} cm{sup -2} s{sup -1} and the day-night difference is found to be (-6.3{+-}4.2(stat.){+-}3.7(sys.))%. There is no evidence of systematic tendencies between the first and second phases.

Journal ArticleDOI
TL;DR: Physiological and biochemical causes for the change in these parameters are discussed and activation energy of Vc max may be the most important for the shift of optimal temperature of photosynthesis at ambient CO2 concentrations.
Abstract: Growth temperature alters temperature dependence of the photosynthetic rate (temperature acclimation). In many species, the optimal temperature that maximizes the photosynthetic rate increases with increasing growth temperature. In this minireview, mechanisms involved in changes in the photosynthesis-temperature curve are discussed. Based on the biochemical model of photosynthesis, change in the photosynthesis-temperature curve is attributable to four factors: intercellular CO2 concentration, activation energy of the maximum rate of RuBP (ribulose-1,5-bisphosphate) carboxylation (Vc max), activation energy of the rate of RuBP regeneration (Jmax), and the ratio of Jmax to Vc max. In the survey, every species increased the activation energy of Vc max with increasing growth temperature. Other factors changed with growth temperature, but their responses were different among species. Among these factors, activation energy of Vc max may be the most important for the shift of optimal temperature of photosynthesis at ambient CO2 concentrations. Physiological and biochemical causes for the change in these parameters are discussed.

Journal ArticleDOI
TL;DR: The association between stroke risk and the pattern of circadian BP variation was analyzed with a Cox proportional hazards model and there was no significant association between total strokerisk and the nocturnal decline in BP (percentage decline from diurnal level) or between total strokes and the morning pressor surge.
Abstract: There is continuing controversy over whether the pattern of circadian blood pressure (BP) variation that includes a nocturnal decline in BP and a morning pressor surge has prognostic significance for stroke risk. In this study, we followed the incidence of stroke in 1430 subjects aged > or =40 years in Ohasama, Japan, for an average of 10.4 years. The association between stroke risk and the pattern of circadian BP variation was analyzed with a Cox proportional hazards model after adjustment for possible confounding factors. There was no significant association between total stroke risk and the nocturnal decline in BP (percentage decline from diurnal level) or between total stroke risk and the morning pressor surge. The cerebral infarction risk was significantly higher in subjects with a or =10% nocturnal decline in BP (P=0.04). The morning pressor surge was not associated with a risk of cerebral infarction. On the other hand, an increased risk of cerebral hemorrhage was observed in subjects with a large morning pressor surge (> or =25 mm Hg; P=0.04). Intracerebral hemorrhage was also observed more frequently in extreme dippers (those with a > or =20% nocturnal decline in BP) than dippers (those with a 10% to 19% decline; P=0.02). A disturbed nocturnal decline in BP is associated with cerebral infarction, whereas a large morning pressor surge and a large nocturnal decline in BP, which are analogous to a large diurnal increase in BP, are both associated with cerebral hemorrhage.

Journal ArticleDOI
TL;DR: A review of the progress of Λ hypernuclear spectroscopy is described and future prospects are presented in this article, where the strengths of the spin-dependent Λ-nucleon interaction in the p -shell region were derived.

Journal ArticleDOI
TL;DR: A higher consumption of green tea is associated with a lower prevalence of cognitive impairment in humans, and the results were essentially the same at cutoffs of <28 and <24.

Journal ArticleDOI
TL;DR: In this article, the authors studied the impact of systematic errors on weak-lensing surveys and computed the requirements on their contributions so that they are not a dominant source of the cosmological parameter error budget.
Abstract: We study the impact of systematic errors on planned weak-lensing surveys and compute the requirements on their contributions so that they are not a dominant source of the cosmological parameter error budget. The generic types of error we consider are multiplicative and additive errors in measurements of shear, as well as photometric redshift errors. In general, more powerful surveys have stronger systematic requirements. For example, for a SuperNova/Acceleration Probe (SNAP)-type survey the multiplicative error in shear needs to be smaller than 1 per cent of the mean shear in any given redshift bin, while the centroids of photometric redshift bins need to be known to be better than 0.003. With about a factor of 2 degradation in cosmological parameter errors, future surveys can enter a self-calibration regime, where the mean systematic biases are self-consistently determined from the survey and only higher order moments of the systematics contribute. Interestingly, once the power-spectrum measurements are combined with the bispectrum, the self-calibration regime in the variation of the equation of state of dark energy w a is attained with only a 20‐30 per cent error degradation. Ke yw ords: cosmological parameters ‐ large-scale structure of Universe.

Journal ArticleDOI
02 Jun 2006-Science
TL;DR: Initial findings about geological features, surface condition, regolith grain size, compositional variation, and constraints on the physical properties of this site are reported by using both scientific and housekeeping data during the descent sequence of the first touchdown.
Abstract: After global observations of asteroid 25143 Itokawa by the Hayabusa spacecraft, we selected the smooth terrain of the Muses Sea for two touchdowns carried out on 19 and 25 November 2005 UTC for the first asteroid sample collection with an impact sampling mechanism. Here, we report initial findings about geological features, surface condition, regolith grain size, compositional variation, and constraints on the physical properties of this site by using both scientific and housekeeping data during the descent sequence of the first touchdown. Close-up images revealed the first touchdown site as a regolith field densely filled with size-sorted, millimeter- to centimeter-sized grains.

Journal ArticleDOI
TL;DR: In this paper, angle-resolved photoemission spectroscopy was used to show that the anisotropy of the pseudogap in k-space and the resulting arcs depend only on the ratio T/T*(x).
Abstract: The response of a material to external stimuli depends on its low-energy excitations. In conventional metals, these excitations are electrons on the Fermi surface—a contour in momentum (k) space that encloses all of the occupied states for non-interacting electrons. The pseudogap phase in the copper oxide superconductors, however, is a most unusual state of matter1. It is metallic, but part of its Fermi surface is ‘gapped out’ (refs 2, 3); low-energy electronic excitations occupy disconnected segments known as Fermi arcs4. Two main interpretations of its origin have been proposed: either the pseudogap is a precursor to superconductivity5, or it arises from another order competing with superconductivity6. Using angle-resolved photoemission spectroscopy, we show that the anisotropy of the pseudogap in k-space and the resulting arcs depend only on the ratio T/T*(x), where T*(x) is the temperature below which the pseudogap first develops at a given hole doping x. The arcs collapse linearly with T/T*(x) and extrapolate to zero extent as T→0. This suggests that the T=0 pseudogap state is a nodal liquid—a strange metallic state whose gapless excitations exist only at points in k-space, just as in a d-wave superconducting state.

Journal ArticleDOI
TL;DR: Drosophila rely entirely on an innate immune response to combat microbial infection, and full-length PGRP-LE acted as an intracellular receptor for monomeric peptidoglycan, whereas a version of PGRp-LE containing only the P GRP domain functioned extracellularly, like the mammalian CD14 molecule.
Abstract: Drosophila rely entirely on an innate immune response to combat microbial infection. Diaminopimelic acid–containing peptidoglycan, produced by Gram-negative bacteria, is recognized by two receptors, PGRP-LC and PGRP-LE, and activates a homolog of transcription factor NF-κB through the Imd signaling pathway. Here we show that full-length PGRP-LE acted as an intracellular receptor for monomeric peptidoglycan, whereas a version of PGRP-LE containing only the PGRP domain functioned extracellularly, like the mammalian CD14 molecule, to enhance PGRP-LC-mediated peptidoglycan recognition on the cell surface. Interaction with the imd signaling protein was not required for PGRP-LC signaling. Instead, PGRP-LC and PGRP-LE signaled through a receptor-interacting protein homotypic interaction motif–like motif. These data demonstrate that like mammals, drosophila use both extracellular and intracellular receptors, which have conserved signaling mechanisms, for innate immune recognition.