Observation of Seven Astrophysical Tau Neutrino Candidates with IceCube

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

Vitamin A-treated natural killer cells reduce interferon-gamma production and support regulatory T-cell differentiation

Natural killer (NK) cells are innate cytotoxic lymphocytes that contribute to immune responses against stressed, transformed, or infected cells. NK cell effector functions are regulated by microenvironmental factors, including cytokines, metabolites, and nutrients. Vitamin A is an essential micronutrient that plays an indispensable role in embryogenesis and development, but was also reported to regulate immune responses. However, the role of vitamin A in regulating NK cell functions remains poorly understood. Here, we show that the most prevalent vitamin A metabolite, all-trans retinoic acid (atRA), induces transcriptional and functional changes in NK cells leading to altered metabolism and reduced IFN-γ production in response to a wide range of stimuli. atRA-exposed NK cells display a reduced ability to support dendritic cell (DC) maturation and to eliminate immature DCs. Moreover, they support the polarization and proliferation of regulatory T cells. These results imply that in vitamin A-enriched environments, NK cells can acquire functions that might promote tolerogenic immunity and/or immunosuppression.

Liver sinusoidal endothelial cells orchestrate NK cell recruitment and activation in acute inflammatory liver injury

Liver sinusoidal endothelial cells (LSECs) rapidly clear lipopolysaccharide (LPS) from the bloodstream and establish intimate contact with immune cells. However, their role in regulating liver inflammation remains poorly understood. We show that LSECs modify their chemokine expression profile driven by LPS or interferon-γ (IFN-γ), resulting in the production of the myeloid- or lymphoid-attracting chemokines CCL2 and CXCL10, respectively, which accumulate in the serum of LPS-challenged animals. Natural killer (NK) cell exposure to LSECs in vitro primes NK cells for higher production of IFN-γ in response to interleukin-12 (IL-12) and IL-18. In livers of LPS-injected mice, NK cells are the major producers of this cytokine. In turn, LSECs require exposure to IFN-γ for CXCL10 expression, and endothelial-specific Cxcl10 gene deletion curtails NK cell accumulation in the inflamed livers. Thus, LSECs respond to both LPS and immune-derived signals and fuel a positive feedback loop of immune cell attraction and activation in the inflamed liver tissue.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

Evidence for neutrino emission from the nearby active galaxy NGC 1068

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy’s active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79 − 20 + 22 neutrinos at tera–electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera–electron volt gamma rays from this source.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

First Report of Pseudomonas cichorii Causing Bacterial vein necrosis on Perilla plants [Perilla frutescens (L.) Britton.] in South Korea

Perilla (Perilla frutescens L.) is the second most important upland crop and the third largest edible oil crop in Korea (Shin and Kim 1994). During a disease survey in Busan, Korea in September 2021, symptoms of vein necrosis were observed in perilla plants, with incidences of approximately 30% and 50% in two fields. Symptoms of spots on the perilla appeared as leaf dryness and spots with water-soaked blotches largely concentrated on the mid-veins of leaves. The lesions were initiated with water-soaked spots on the leaf or stem and gradually turned black or brown. Necrosis was also observed in the stems. A bacterium was isolated on Luria-Bertani (LB) agar from diseased leaf tissues that were surface-disinfected with 70% ethyl alcohol for 3-5 min and then washed with sterile water three times. Three pieces of sterilized leaf tissue (size: 0.5 × 0.5 cm) were mixed with 500 µL sterile water for 30 min, and then the suspension was serially diluted and spread on LB agar. Subsequently, isolates were cultivated on LB agar and King's Medium B agar (KMB) (Schaad et al. 2001), and they were predominantly cream-colored and circular bacterial colonies with undulated margins. The bacterial colonies on KMB displayed fluorescence under 365 nm UV light. The isolates were analyzed with the GEN III MicroPlate (Biolog, Hayward, CA, USA), and all isolates were identified as Pseudomonas cichorii, a devastating plant bacterium that damages a wide range of host plants worldwide, including in South Korea (Hikichi et al. 2013; Ramkumar et al. 2015). To identify the species of the bacterial pathogen, genomic DNA of four isolates (BS4922, BS4167, BS4345, and BS4560) was extracted, and the 16S rRNA gene and hrcRST gene were amplified with universal primers, 27F/1492R and Hcr1/Hcr2, and sequencing was then done (Patel et al. 2019). In the BLAST analysis, the 16S rRNA sequences (GenBank OM060656, OM275434, OM275435, OM275436) showed a 100% and 99% similarity to P. cichorii strains MAFF 302698 (AB724286) and P. cichorii strain Pc-Gd-4 (KU923373), respectively. Further, hrcRST gene sequences (GenBank OM143596, OM268864, OM268865, and OM268866) showed high similarity (>99%) with P. cichorii strain P16-51 (MG518230). A pathogenicity test of the four isolates was performed on 3 - 4 weeks old perilla plants by creating wounds with a needle on the lower leaves and stems, and then the plants were inoculated by spraying inoculum (108 CFU/ml). The plants that served as the negative control were wounded and sprayed with unsterilized water. The inoculated perilla plants were placed in a greenhouse at 28 ± 2oC , 80-85% relative humidity, and a natural photoperiod. The inoculation site began to show symptoms of water-soaked brown lesions. Disease symptoms such as leaf dryness, water-soaked blotches on the mid-vein of leaves, and necrosis on plant stems were observed in the inoculated plants 7-10 days after inoculation, whereas the plants of the negative control group did not show any symptoms. The bacteria were re-isolated from the diseased tissues of the plants, and DNA sequence analysis identified them as P. cichorii. Additionally, all isolates induced hypersensitivity reactions in tobacco and tomato leaves within 24 h after inoculation. To our knowledge, this is the first report of P. cichorii infecting perilla in South Korea. The findings in this study will provide the basic information for the development of diagnostic tools and management measures against P. cichorii in perilla.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

Association of beta-blockers or inhibitors of renin-angiotensin system with clinical outcomes in patients with mid-range left ventricular ejection fraction after acute myocardial infarction

Background

In the era of the initial optimal interventional and medical therapy for acute myocardial infarction (AMI), a number of patients with mid-range left ventricular ejection fraction (EF) (>40%, <50%) becomes increasing.

Purpose

This observational study aimed to investigate the association between oral beta-blockers or inhibitors of renin-angiotensin system (RAS) and 2-year clinical outcomes in patients with mid-range EF after AMI.

Methods

Among 13,624 patients enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH), propensity-score matched patients who survived the initial attack and had mid-range EF were selected according to beta-blocker or RAS inhibitor therapy at discharge.

Results

Beta-blocker therapy at discharge was associated with lower 2-year major adverse cardiac events (MACE) of cardiac death, MI, revascularization or re-hospitalization due to heart failure (8.7 vs. 12.8/100 person-year; hazard ratio [HR] 0.68; 95% confidence interval [CI] 0.50–0.93; P=0.015), and no significant interaction between EF ≤45% and >45% was observed (P for interaction=0.354). This association was mainly driven by lower MI in patients with beta-blockers (1.6 vs. 3.1/100 person-year; HR 0.50; 95% CI 0.26–0.95; P=0.035). Inhibitors of RAS at discharge were not associated with lower 2-year MACE, but with lower re-hospitalization due to heart failure (1.8 vs. 3.5/100 person-year; HR 0.53; 95% CI 0.33–0.86; P=0.010) without significant interaction between EF ≤45% and >45% (P for interaction=0.333).

Conclusions

Beta-blockers or RAS inhibitors at discharge were associated with better 2-year clinical outcomes without significant interaction between ≤45% and >45% in patients with mid-range EF after AMI.</ef<50%)>

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Korea Centers for Disease Control and Prevention. 2-year clinical outcomes

Engineered ionizable lipid nanoparticles for targeted delivery of RNA therapeutics into different types of cells in the liver

Ionizable lipid nanoparticles (LNPs) have been widely used for in vivo delivery of RNA therapeutics into the liver. However, a main challenge remains to develop LNP formulations for selective delivery of RNA into certain types of liver cells, such as hepatocytes and liver sinusoidal endothelial cells (LSECs). Here, we report the engineered LNPs for the targeted delivery of RNA into hepatocytes and LSECs. The effects of particle size and polyethylene glycol-lipid content in the LNPs were evaluated for the hepatocyte-specific delivery of mRNA by ApoE-mediated cellular uptake through low-density lipoprotein receptors. Targeted delivery of RNA to LSECs was further investigated using active ligands. Incorporation of mannose allowed the selective delivery of RNA to LSECs, while minimizing the unwanted cellular uptake by hepatocytes. These results demonstrate that engineered LNPs have great potential for the cell type-specific delivery of RNA into the liver and other tissues.

eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1  TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

P5996HDAC inhibition improves myofibrillar relaxation and metabolism in a feline model of HFpEF

Background

Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for about 50% of all cases of HF and there are currently no effective therapies.

Purpose

To assess the effects of histone deacetylase (HDAC) inhibition on cardiac and mitochondrial function and the plasma metabolome in a large mammalian model of slow-progressive pressure overload with features of HFpEF.

Methods

Male domestic short hair cats (n=26, aged 2mo), underwent either sham (S) procedures (n=5) or aortic constriction with a customized pre-shaped band (n=21), resulting in slow progressive pressure overload during growth. 2 months post-banding, animals were treated daily with either 10mg/kg suberoylanilide hydroxamic acid (b+SAHA) (n=8), a pan-HDAC inhibitor, or vehicle (b+veh) (n=8) for 2 months. Serial in-vivo cardiopulmonary phenotyping was performed monthly, and invasive hemodynamic and gas exchange parameters were evaluated 4 months post-banding. Ex-vivo myofibril mechanical studies and blood-based metabolomic profiling were performed. Data is presented as mean±SEM.

Results

Echocardiography at 4-months post-banding revealed that b+SAHA animals had a significant reduction in left ventricular hypertrophy (LVH) and LA size vs. b+veh animals. Left ventricular end-diastolic pressure (LVEDP) and mean pulmonary arterial pressure (mPAP) were significantly lower in b+SAHA vs. b+veh. SAHA treatment also improved ex-vivo myofibril relaxation independent of LVH and this effect correlated with in-vivo improvements of LV relaxation. Furthermore, SAHA treatment preserved lung structure, and improved lung compliance and oxygenation, reflected by a decrease in alveolar-capillary wall thickness and intrapulmonary shunt. SAHA treatment also reduced perivascular fluid cuffs around extra-alveolar vessels, suggesting attenuated alveolar-capillary stress failure. Treatment with SAHA caused an increase in both oxygen consumption in-vivo and the percentage of type 1 skeletal muscle fibers (higher oxidative capacity). SAHA also increased mRNA levels of coactivators that regulate mitochondrial function and induced metabolic reprogramming towards mitochondrial oxidation preferentially utilizing fatty acids. SAHA treated HeLa cells showed a significant increase in oxidative phosphorylation and ATP production.

Effects of SAHA

Conclusion

These results show that slow-progressive pressure overload mimics critical features of HFpEF. SAHA can improve cardiac, pulmonary, and metabolic derangements caused by chronic pressure overload. Therefore, HDAC inhibition may be an interesting therapeutic strategy to treat the ever growing HFpEF population.

Acknowledgement/Funding

NIH [HL33921 to S.R.H, HL116848, HL127240 to T.A.M]; AHA [16SFRN31400013 to T.A.M.]; Medical University of Graz [M.W.], Stadt Graz [M.W.]

Constraints on Minute-Scale Transient Astrophysical Neutrino Sources

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5}  erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52}  erg. A hypothetical population of transient sources has to be more common than 10^{-5}  Mpc^{-3}  yr^{-1} (5×10^{-8}  Mpc^{-3}  yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

Search for neutrinos from decaying dark matter with IceCube: IceCube Collaboration

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino 'track' events from the Northern Hemisphere, while the second analysis uses 2 years of 'cascade' events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than10 28 s at 90% CL for dark matter masses above 10 TeV .

Note: Commercial SQUID magnetometer-compatible NMR probe and its application for studying a quantum magnet

We present a compact nuclear magnetic resonance (NMR) probe which is compatible with a magnet of a commercial superconducting quantum interference device magnetometer and demonstrate its application to the study of a quantum magnet. We employ trimmer chip capacitors to construct an NMR tank circuit for low temperature measurements. Using a magnetic insulator MoOPO₄ with S = 1/2 (Mo⁵⁺) as an example, we show that the T-dependence of the circuit is weak enough to allow the ligand-ion NMR study of magnetic systems. Our ³¹P NMR results are compatible with previous bulk susceptibility and neutron scattering experiments and furthermore reveal unconventional spin dynamics.

Lipid abnormalities in atopic skin are driven by type 2 cytokines

Lipids in the stratum corneum of atopic dermatitis (AD) patients differ substantially in composition from healthy subjects. We hypothesized that hyperactivated type 2 immune response alters AD skin lipid metabolism. We have analyzed stratum corneum lipids from nonlesional and lesional skin of AD subjects and IL-13 skin-specific Tg mice. We also directly examined the effects of IL-4/IL-13 on human keratinocytes in vitro. Mass spectrometric analysis of lesional stratum corneum from AD subjects and IL-13 Tg mice revealed an increased proportion of short-chain (N-14:0 to N-24:0) NS ceramides, sphingomyelins, and 14:0-22:0 lysophosphatidylcholines (14:0-22:0 LPC) with a simultaneous decline in the proportion of corresponding long-chain species (N-26:0 to N-32:0 sphingolipids and 24:0-30:0 LPC) when compared with healthy controls. An increase in short-chain LPC species was also observed in nonlesional AD skin. Similar changes were observed in IL-4/IL-13-driven responses in Ca2+-differentiated human keratinocytes in vitro, all being blocked by STAT6 silencing with siRNA. RNA sequencing analysis performed on stratum corneum of AD as compared with healthy subjects identified decreased expression of fatty acid elongases ELOVL3 and ELOVL6 that contributed to observed changes in atopic skin lipids. IL-4/IL-13 also inhibited ELOVL3 and ELOVL6 expression in keratinocyte cultures in a STAT6-dependent manner. Downregulation of ELOVL3/ELOVL6 expression in keratinocytes by siRNA decreased the proportion of long-chain fatty acids globally and in sphingolipids. Thus, our data strongly support the pathogenic role of type 2 immune activation in AD skin lipid metabolism.

Measurement of the ν μ energy spectrum with IceCube-79: IceCube Collaboration

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The ν μ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of a multivariate classification process based on machine learning. The subsequent unfolding was performed using the software Truee. The resulting spectrum covers an E ν -range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows an excess of more than 1.9 σ in four adjacent bins for neutrino energies E ν ≥ 177.8 TeV . The obtained spectrum is fully compatible with previous measurements of the atmospheric neutrino flux and recent IceCube measurements of a flux of high-energy astrophysical neutrinos.

Magnetic-Order Crossover in Coupled Spin Ladders

We report a novel crossover behavior in the long-range-ordered phase of a prototypical spin-1/2 Heisenberg antiferromagnetic ladder compound (C_{7}H_{10}N)_{2}CuBr_{4}. The staggered order was previously evidenced from a continuous and symmetric splitting of ^{14}N NMR spectral lines on lowering the temperature below T_{c}≃330  mK, with a saturation towards ≃150  mK. Unexpectedly, the split lines begin to further separate away below T^{*}∼100  mK, while the linewidth and the line shape remain completely invariable. This crossover behavior is further corroborated by the NMR relaxation rate T_{1}^{-1} measurements. A very strong suppression reflecting the ordering, T_{1}^{-1}∼T^{5.5}, observed above T^{*}, is replaced by T_{1}^{-1}∼T below T^{*}. These original NMR features are indicative of the unconventional nature of the crossover, which may arise from a unique arrangement of the ladders into a spatially anisotropic and frustrated coupling network.

Expression of IL-22 in the Skin Causes Th2-Biased Immunity, Epidermal Barrier Dysfunction, and Pruritus via Stimulating Epithelial Th2 Cytokines and the GRP Pathway

Increased expression of Th22 cytokine IL-22 is a characteristic finding in atopic dermatitis (AD). However, the specific role of IL-22 in the pathogenesis of AD in vivo has yet to be elucidated. Consistent with observations in human AD, IL-22 was significantly increased in the AD skin of mice after epicutaneous sensitization to house dust mite allergen. Utilizing a skin-specific inducible transgenic system, we show in the present study that expression of IL-22 in the skin of mice caused an AD-like phenotype characterized by chronic pruritic dermatitis associated with Th2-biased local and systemic immune responses, downregulation of epidermal differentiation complex genes, and enhanced dermatitis upon epicutaneous allergen exposure. IL-22 potently induced the expression of gastrin-releasing peptide (GRP), a neuropeptide pruritogen, in dermal immune cells and sensory afferents and in their skin-innervating sensory neurons. IL-22 also differentially upregulated the expression of GRP receptor (GRPR) on keratinocytes of AD skin. The number of GRP+ cells in the skin correlated with the AD severity and the intensity of pruritus. IL-22 directly upregulated the expression of epithelial-derived type 2 cytokines (thymic stromal lymphopoietin and IL-33) and GRP in primary keratinocytes. Furthermore, GRP not only strongly induced thymic stromal lymphopoietin but it also increased the expression of IL-33 and GRPR synergistically with IL-22. Importantly, we found that the expression of GRP was strikingly increased in the skin of patients with AD. These results indicate that IL-22 plays important pathogenic roles in the initiation and development of AD, in part through inducing keratinocyte production of type 2 cytokines and activation of the GRP/GRPR pathway.

Effect of introducing Fe2O3 into CeO2–ZrO2 on oxygen release properties and catalytic methane combustion over PdO/CeO2–ZrO2–Fe2O3/γ-Al2O3 catalysts

Novel PdO/CeO₂–ZrO₂–Fe₂O₃/γ-Al₂O₃ catalysts were synthesized for methane combustion.

Constraints on Ultrahigh-Energy Cosmic-Ray Sources from a Search for Neutrinos above 10 PeV with IceCube

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9}  GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5}  GeV to above 10^{11}  GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6}  GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5}  GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

Dichotomy between Attractive and Repulsive Tomonaga-Luttinger Liquids in Spin Ladders

We present a direct NMR method to determine whether the interactions in a Tomonaga-Luttinger liquid (TLL) state of a spin-1/2 Heisenberg antiferromagnetic ladder are attractive or repulsive. For the strong-leg spin ladder compound (C_{7}H_{10}N)_{2}CuBr_{4} we find that the isothermal magnetic field dependence of the NMR relaxation rate T_{1}^{-1}(H) displays a concave curve between the two critical fields bounding the TLL regime. This is in sharp contrast to the convex curve previously reported for a strong-rung ladder, (C_{5}H_{12}N)_{2}CuBr_{4}. We show that the concavity and the convexity of T_{1}^{-1}(H), which is a fingerprint of spin fluctuations, directly reflect the attractive and repulsive fermionic interactions in the TLL, respectively. The interaction sign is alternatively determined from an indirect method combining bulk magnetization and specific heat data.

Searches for Sterile Neutrinos with the IceCube Detector

The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{μ} or ν[over ¯]_{μ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3  eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.

USP8 suppresses death receptor-mediated apoptosis by enhancing FLIPL stability

FLICE-like inhibitory protein (FLIP) is a critical regulator of death receptor-mediated apoptosis. Here, we found ubiquitin-specific peptidase 8 (USP8) to be a novel deubiquitylase of the long isoform of FLIP (FLIP_L). USP8 directly deubiquitylates and stabilizes FLIP_L, but not the short isoform. USP8 depletion induces FLIP_L destabilization, promoting anti-Fas-, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)- and tumor necrosis factor alpha-induced extrinsic apoptosis by facilitating death-inducing signaling complex or TNFR1 complex II formation, which results in the activation of caspase-8 and caspase-3. USP8 mRNA levels are elevated in melanoma and cervical cancers, and the protein levels of USP8 and FLIP_L are positively correlated in these cancer cell lines. Xenograft analyses using ME-180 cervical cancer cells showed that USP8 depletion attenuated tumor growth upon TRAIL injection. Taken together, our data indicate that USP8 functions as a novel deubiquitylase of FLIP_L and inhibits extrinsic apoptosis by stabilizing FLIP_L.

Dimensional Reduction in Quantum Dipolar Antiferromagnets

We report ac susceptibility, specific heat, and neutron scattering measurements on a dipolar-coupled antiferromagnet LiYbF_{4}. For the thermal transition, the order-parameter critical exponent is found to be 0.20(1) and the specific-heat critical exponent -0.25(1). The exponents agree with the 2D XY/h_{4} universality class despite the lack of apparent two-dimensionality in the structure. The order-parameter exponent for the quantum phase transitions is found to be 0.35(1) corresponding to (2+1)D. These results are in line with those found for LiErF_{4} which has the same crystal structure, but largely different T_{N}, crystal field environment and hyperfine interactions. Our results therefore experimentally establish that the dimensional reduction is universal to quantum dipolar antiferromagnets on a distorted diamond lattice.

Aspergillus oryzae fermented germinated soybean extract alleviates perimenopausal symptoms in ovariectomised rats

BACKGROUND

Soybeans have been widely used to alleviate climacteric symptoms. In this study, we investigated the oestrogenic activities of isoflavones extracted from Aspergillus oryzae-challenged germinated soybeans (AO-GS). Eight-week-old virgin Sprague-Dawley female rats were ovariectomised (OVX). The rats were orally administered 0.1 mg kg(-1) 17α-ethinyl oestradiol or three different doses of AO-GS (0.5, 1.0 2.0 g kg(-1) day(-1)) in distilled water for 6 weeks, while control rats were administered vehicle alone. Uterine weights and levels of oestradiol and testosterone in serum were measured. In addition to serum parameters, bone parameters were also acquired by using micro-computed tomography scanning.

RESULTS

Treatments of OVX rats with AO-GS changed the secretory profile of serum oestradiol and testosterone. Serum oestradiol levels were significantly increased in OVX rats treated with and AO-GS (0.5, 1.0, 2.0 g kg(-1) day(-1)), while serum testosterone levels were not significantly increased in OVX rats treated with 1.0 g kg(-1) day(-1) of AO-GS. Furthermore, AO-GS (2.0 g kg(-1) day(-1)) significantly attenuated bone loss, increased trabecular bone volume fraction and trabecular thickness, and significantly decreased trabecular pattern factor.

CONCLUSION

AO-GS treatments caused moderate oestrogenic activity in OVX rats compared to those treated with oestradiol, suggesting the potential for the use of AO-GS in the treatment of menopausal symptoms and in osteoporosis caused by oestrogen deficiency.

Photoprotective effects of galacto-oligosaccharide and/or Bifidobacterium longum supplementation against skin damage induced by ultraviolet irradiation in hairless mice

This study aimed at examining whether oral administration of galacto-oligosaccharide (GOS) and Bifidobacterium longum, individually or in combination, could exert photoprotective effects on the skin of hairless mice. GOS and/or Bifidobacterium were administered orally to hairless mice for 12 weeks. Mice were irradiated with UV light daily for four consecutive days. GOS administration increased the water-holding capacity of the skin and prevented transepidermal water loss compared with the control. A reduction in the erythema formation of 16.8% was also observed in the GOS-treated group compared with the control, and CD44 gene expression was significantly increased. Oral administration of GOS or Bifidobacterium significantly increased TIMP-1 and Col1 mRNA expression compared with the control. Our findings support that prebiotics, including GOS, are beneficial not only to the intestine, but also to the skin, and present the possibility of new nutritional strategies for the prevention of UV-induced skin damage.

Role of proton pump inhibitors in preventing hypergastrinemia-associated carcinogenesis and in antagonizing the trophic effect of gastrin

Gastrin is the main hormone stimulating gastric acid secretion, but it exerts proliferative and anti-apoptotic actions on various cancer cell types, in addition to its well-known trophic effect on enterochromaffin-like cells. As treatment with proton pump inhibitors (PPIs) increases the biosynthesis and secretion of gastrin, it has been postulated that treatment with PPIs could increase the risk of cancer, especially in Barrett's esophagus, gastric carcinoids, and colorectal cancer (CRC). Some tumors produce gastrin of their own, which can act in an autocrine manner to promote tumor growth. In addition, gastrin is known to foster the tumor microenvironment. However, in spite of these potentially increased cancer risks due to PPI-induced hypergastrinemia, prospective, large-scale cohort studies did not show an increase in CRC prevalence. The question as to why the long-term use of PPIs was not associated with an increased cancer risk of CRC might be answered by the fact that the PPIs antagonized the trophic effects of hypergastrinemia. Furthermore, the blockade of proton pumps or potassium channels in cancer cells could limit the abnormal glycolytic energy metabolism of cancer cells. Apart from their suppressive effect on gastric acids, PPIs exert an anti-tumor effect through the selective induction of apoptosis as well as an anti-inflammatory effect, and they protect cells from developing chemo- or radiotherapeutic resistance. Moreover, the anti-carcinogenic actions of PPIs were augmented with PPI-induced hypergastrinemia. Together with their potential targeted killing of cancer stem cells, these effects demonstrate their potential anti-cancer actions.

Attractive Tomonaga-Luttinger liquid in a quantum spin ladder

We present NMR measurements of a strong-leg spin-1/2 Heisenberg antiferromagnetic ladder compound (C7H10N)2CuBr4 under magnetic fields up to 15 T in the temperature range from 1.2 K down to 50 mK. From the splitting of NMR lines, we determine the phase boundary and the order parameter of the low-temperature (three-dimensional) long-range-ordered phase. In the Tomonaga-Luttinger regime above the ordered phase, NMR relaxation reflects characteristic power-law decay of spin correlation functions as 1/T1∝T(1/2K-1), which allows us to determine the interaction parameter K as a function of field. We find that field-dependent K varies within the 1<K<2 range, which signifies attractive interaction between the spinless fermions in the Tomonaga-Luttinger liquid.

Field-induced freezing of a quantum spin liquid on the kagome lattice

We report (17)O NMR measurements in the S=1/2 (Cu(2+)) kagome antiferromagnet Herbertsmithite ZnCu(3)(OH)(6)Cl(2) down to 45 mK in magnetic fields ranging from 2 to 12 T. While Herbertsmithite displays a gapless spin-liquid behavior in zero field, we uncover an instability toward a spin-solid phase at sub-Kelvin temperature induced by an applied magnetic field. The latter phase shows largely suppressed moments ≲0.1 μ(B) and gapped excitations. The H-T phase diagram suggests the existence of a quantum critical point at the small but finite magnetic field μ(0)H(c)=1.55(25) T. We discuss this finding in light of the perturbative Dzyaloshinskii-Moriya interaction which was theoretically proposed to sustain a quantum critical regime for the quantum kagome Heisenberg antiferromagnet model.