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.

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.

"Weight of the World" and "I Want Them to Know": Skilled Nursing Facility Administrators' Perspectives on COVID-19 in Research Poems

COVID-19 has had a drastic, long-lasting impact on skilled nursing facilities (SNFs), forcing communities to continuously adapt to rapidly changing guidelines, restrictions, and challenges. In spring 2020, we conducted a sequential mixed-methods study with administrators of SNFs in the Midwest to understand the experience of administrators, staff, and residents during the pandemic. We collected 60 surveys with open-ended items related to the impact of the pandemic on communities as a whole, staff, and residents. Survey findings informed supplemental interviews with six administrators working in diverse regions. Due to the affective nature of the data, we present the findings in two found poems, which emphasize the lyrical, emotional, and poignant aspects of the participant voices. The first poem, Weight of the World, captures the struggle to adapt during the transition into the pandemic and its negative impacts on the lives of residents and their families. The second, I Want Them to Know, describes the resiliency with which administrators and staff responded to adversity while maintaining motivation to continue the work in the midst of unprecedented challenges. The two poems offer contrasting or balancing narratives of struggle and survival during the pandemic era.

POLICIES AND PERSPECTIVES AROUND SEXUAL ACTIVITIES AMONG RESIDENTS WITH COGNITIVE IMPAIRMENT OR DEMENTIA IN LTC

Many older adults remain sexually interested and active in later life. However, little is known about how sexual policies and practices in skilled-nursing facilities (SNF) address sexual activities of residents with cognitive impairment and dementia. This study seeks to identify the current sexual policies and staff’s perspectives related to residents with cognitive impairment or dementia in SNFs in Kansas. Online surveys and mailed surveys were distributed to administrators from all 364 SNFs in Kansas in June 2020. 60 long-term care facilities (16.5%) answered the survey. Of 60 survey respondents, 22 facilities (36.7%) have a policy addressing sexual expression and 19 of those policies (94.7%) address issues related to cognitive impairment, competency, or dementia. 77.4% had trained their staff on the impact on sexual expression for those with cognitive impairment or dementia once or more than once during the past year. 73.3% of administrators stated that their staff would respond differently to sexual expression among individuals with dementia or cognitive impairment compared to other residents, often noting issues related to consent and capacity. 55.2% reported any sexual expression among residents with dementia within the past year. Findings indicated that there is a lack of overall sexual policies, but those that exist are likely to address residents with cognitive impairment or dementia. Although there is evidence of training and attention to issues related to sexual expression in individuals with dementia or cognitive impairment, there is a need for further efforts to establish practice norms and policies around more complex or nuanced situations.

Representations of older adults in COVID-related newspaper articles: A comparison between the perspectives of older and younger adults

During the COVID-19 pandemic, media sources discussed diverse perspectives on aging and older adults, providing opportunities to examine representations of older adults during times of crisis. This study aims to explore representations of older adults during the first month of the pandemic in the U.S. by comparing the perspectives of older and younger adults in national newspapers. A systematic search identified 115 articles published in four major newspapers in the U.S. between March 11 and April 10, 2020, in which older and younger adults were quoted on topics related to the intersection of COVID-19 and aging. Quotes were inductively reviewed using content and thematic analytic strategies. A total of 265 quotes were identified from older adults (n = 104, 39%) and younger adults (n = 161, 61%). We identified three primary themes: impacts on "vulnerable" older adults, debates over the value of older adults' lives, and a counternarrative of resiliency. Older adults were represented as a vulnerable group during the pandemic, in need of protection and support, while debates over the value of their lives similarly evoke images of frailty and dependency. Such depictions frame older adults as a burden on society and reduce their agency and subjectivity. Ageist biases were not only present in quotes from public figures and professionals, but also evident in quotes from older adults themselves. However, older adults also spoke to their own resiliency, survival, and strengths, thereby positioning themselves as elders worthy of respect and able to share wisdom with younger generations. These findings highlight the importance of listening to older adults' voices in order to understand their experiences from their own perspectives through their own agentive positioning and promoting intentionally age-positive and nuanced representations of older adults in public discourse.

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.

Sexual Expression, Policies, and Practices in Skilled Nursing Settings Serving Older Adults: An Updated Assessment in the State of Kansas

Doll assessed sexual expressions, policies, and practices in Skilled Nursing Facilities (SNFs) in the state of Kansas. This study provided an updated and expanded assessment. A mixed-methods survey was distributed to administrators of all SNFs in the state of Kansas. Among 60 administrations, 84% reported any sexual expression among residents in their community within the past year and 55% reported expressions involving an individual with cognitive impairment. In response to sexual expressions, 70% of administrators believe staff would treat residents with dignity and respect and about 40% anticipated staff discomfort. About 40% of administrators reported having a policy related to sexual expression. Attitudes and responses of staff and administrators appear to be shifting in a sex-positive direction. While policies related to sexuality are more common than a decade ago, there is room for additional uptake, standardization, and infusion of person-centered language and practices.

Multiple Streams Analysis of the Long-Term Care Insurance in South Korea: Understanding Policy Changes (2008 - 2014)

The Long-Term Care Insurance (LTCI) Act in South Korea was enacted in 2008 to improve the quality of life of older adults by promoting better health and to mitigate the burden of care on family members. In 2014, the Enforcement Decree for the LTCI Act was revised to broaden criteria for eligible recipients of LTCI-related services and care. This policy analysis seeks to explore the political circumstances under which the Act was formed and how social environmental factors had evolved to revise the LTCI Act using a multiple streams policy analysis framework. A combination of factors influenced the status of LTCI policy agenda, including shifts in aged demographic structure and increasing medical expenditures. From the Korean National Dementia Plan, a pilot project of dementia care was conducting to prove the efficiency of dementia care service. While the Korean Senior Citizens Association (KSCA) was less successful gaining press attention around dementia care, the presidential election and candidates’ election pledges were key factors to suddenly open the opportunity to extend the recipients for dementia care. The process through which the LTCI Act was revised and expanded showed the importance of the political environment associated with the election. Based on the recognition of LTIC policy agenda and already testing the efficiency of dementia care services, the election leaded to revision of LTCI Act and it quickly diffused by the new administration. From the revision of LTCI, international policymakers and scholars should recognize how the political events might use the policy for older adutls.

Sexual Expression, Policy, and Practices in Skilled Nursing Facilities: An Updated Assessment in the State of Kansas

Prior studies have reported barriers to meeting the sexual needs of older adults within skilled-nursing facilities, such as a lack of privacy, lack of supportive practices and policies, and judgement or discomfort on the part of the staff (Doll, 2013; Hajjar & Kamel, 2003). In 2008, Doll and colleagues assessed the scope of sexual behaviors, staff perceptions of and responses to such behaviors, and whether facilities had a sexual policy in place in SNFs in the state of Kansas (Doll, 2013). In the present study, an online survey was distributed to the same population to provide an updated assessment of sexual behaviors, policies, and practices. Of 60 survey respondents, 62.7% reported knowledge of individual sexual acts (e.g., masturbation) within the past year and 34.5% reported interactional (between two or more residents) sexual acts. When encountering a sexual event, staff were most likely to report the incident to an administrator (76.7%) and treat residents with respect (70.0%), while 35.0% and 41.7% were expected to respond with embarrassment and discomfort, respectively. Only 40% of administrators reported having a policy related to sexual expression. Findings indicate that staff are likely to respond differently to LGBTQ residents due to discomfort and those living with cognitive impairment due to concerns related to consent. The proportion of facilities in Kansas with policies related to sexual expression has increased from 26% to 40% in the past 12 years, but there remains a need for greater specificity of sexuality-related policies and trainings.

Psychological Challenges Among Older Adults with Early Stage Dementia: A Narrative Literature Review

Subjective cognitive decline (SCD) is a self-reported decline in cognition among otherwise cognitively healthy older adults. It is believed that SCD may be a precursor to Alzheimer’s Disease (AD). Analyzing data from the Canadian Longitudinal Study on Aging (CLSA), a large national sample of participants aged 45-85 at baseline, we sought to identify prospective relationships between health-related behaviors and SCD. Exposures were measured at baseline and SCD was measured three years later, with the question: “Do you feel like your memory is becoming worse?”. A multivariable logistic regression model was used to estimate odds of SCD (analytic sample: n=35,680). Alcohol consumption was associated with increased odds of SCD, with regular drinkers (OR=1.13, 95% CI: 1.04, 1.22) and frequent drinkers (OR=1.17, 95% CI: 1.08, 1.27) more likely to report SCD than never drinkers. Compared to participants who never smoked, former smokers had increased odds of SCD (OR=1.13, 95% CI: 1.08, 1.18), whereas current smokers had reduced odds of SCD (OR=0.90, 95% CI: 0.83, 0.98). Participants who consumed five or more servings of fruits/ vegetables had reduced odds of SCD (OR=0.95, 95% CI: 0.91, 0.99), when compared to those who consumed <5 servings. Lastly, we did not observe any associations between walking and SCD. This study identifies relationships between various health-related behaviors and SCD in a large population-based sample of older Canadians. Identification of modifiable risk factors may help with early prevention and intervention of SCD.

Representation of Older Adults in COVID-Related Newspaper Coverage

Based on clinical and epidemiological evidence, COVID-19 infection can occur in people of all ages; however, the media typically focuses its attention on the vulnerability of older adults and individuals with chronic illnesses. This study aims to explore the representation of older adults during the first month of the pandemic in the U.S. by comparing the narratives of older adults and younger adults in national media sources. A systematic search identified 115 articles published in four major newspapers in the U.S. included USA Today, The New York Times, Los Angeles Times, and The Washington Post between March 11 and April 10, 2020 in which older adults and younger adults were quoted on topics related to the intersection of COVID-19 and aging. Quotes were inductively reviewed using thematic content analysis. In 115 articles, there were 265 quotes from older adults (n=104, 39%) and younger adults (n=161, 61%). When comparing patterns that were common or distinctive between older and younger individuals quoted, three key themes emerged: 1) impacts of COVID-19 on older adults and resulting vulnerability, 2) debated perspectives over the value of older adults’ lives, and 3) a counternarrative of resiliency among older adults. This study provides the opportunity to understand how the pandemic may impact representations of older adults and findings emphasize the importance of voice among older adults to combat ageist messaging and promote counternarratives to assumptions of vulnerability. Also, it suggests for policymakers and practitioners to insight into how the representation of older adults is disseminated by media.

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) (&gt;40%, &lt;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 &gt;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 &gt;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 &gt;45% in patients with mid-range EF after AMI.&lt;/ef&lt;50%)&gt;

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

Ageism in COVID-Related Newspaper Coverage: The First Month of a Pandemic

Objectives

Media sources have consistently described older adults as a medically vulnerable population during the coronavirus disease 2019 (COVID-19) pandemic, yet a lack of concern over their health and safety has resulted in dismissal and devaluation. This unprecedented situation highlights ongoing societal ageism and its manifestations in public discourse. This analysis asks how national news sources performed explicit and implicit ageism during the first month of the pandemic.

Method

Using content and critical discourse analysis methods, we analyzed 287 articles concerning older adults and COVID-19 published between March 11 and April 10, 2020, in 4 major U.S.-based newspapers.

Results

Findings indicate that while ageism was rarely discussed explicitly, ageist bias was evident in implicit reporting patterns (e.g., frequent use of the term “elderly,” portrayals of older adults as “vulnerable”). Infection and death rates and institutionalized care were among the most commonly reported topics, providing a limited portrait of aging during the pandemic. The older “survivor” narrative offers a positive alternative by suggesting exceptional examples of resilience and grit. However, the survivor narrative may also implicitly place blame on those unable to survive or thrive in later life.

Discussion

This study provides insight for policy makers, researchers, and practitioners exploring societal perceptions of older adults and how these perceptions are disseminated and maintained by the media.

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.

Ageism in COVID-19-Related Media Coverage: Examining Publications During the First Month of the Pandemic

The media has consistently described older adults as the population most vulnerable to COVID-19. Anti-ageism critics have taken issue with the oft-repeated statement that “only” older adults are at risk, a construction that dismisses and devalues the nuances within this population. The purpose of this study was to analyze instances of ageism in national media sources during the first month of the COVID-19 pandemic. A systematic search returned 287 articles concerning older adults and COVID-19 published in four major newspapers in the United States—USA Today, The New York Times, Los Angeles Times, and The Washington Post—between March 11 and April 10, 2020. Combining the strengths of content analysis and critical discourse analysis, we deductively and inductively reviewed the articles for patterns related to implicit and explicit forms of ageism. While ageism was rarely discussed explicitly, ageist bias was evident in implicit reporting patterns, such as frequent use of the phrase the elderly, which was often paired with statements describing older adults as vulnerable. Infection and death rates among older adults, as well as institutionalized care practices, were among the most commonly reported topics, providing a limited portrait of aging during the pandemic. While some authors utilized a survivor narrative by portraying older adults as having survived hardships, this construction implicitly places blame on those unable to do so. Older adults, when quoted directly, produced more complex and nuanced narratives of aging during the COVID-19 pandemic. Such narratives can combat societal ageism and promote self-determination and -definition.

"You'll See": Younger Women Interviewing Older Women in Qualitative Research

Understanding the co-construction of the interview process between older adult research participants and relatively younger interviewers requires a nuanced analysis of positioning, reflexivity, and power within interviewing dynamics, accounting for differences in historical context and lived experience. Guided by a feminist life span approach, this study examined interviewing dynamics between a younger woman interviewer and older women research participants, ages 57-93 (mean = 65.3), in two qualitative studies completed five years apart. Four themes emerged: 1) contrasting experiences drew explicit attention to discrepancies in historical context, age, and life experience between participants and the interviewer. Similarities often arose in the theme of 2) invoking expertise in which participants oriented to or invoked their own expertise in their life story and experiences and the interviewer's expertise in research, sexuality studies, and social services. Participants enacted 3) demonstrating care, by prioritizing the researcher's goals, offering advice, and expressing hopes for younger generations. Finally, 4) the participants and researcher used distinctive conversational strategies when addressing challenging or sensitive topics. This paper contributes a needed analysis of age-related dynamics in qualitative research as well as indicating potential strategies to inform reflexive cross-generational conversations in gerontological research and practice more broadly.

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.

YOU’LL SEE: YOUNGER RESEARCHERS INTERVIEWING OLDER PARTICIPANTS

In qualitative research, similarities and differences between the participant and researcher influence the research process and dynamics. Specifically, the age difference between older participants and relatively younger qualitative researchers is a common, but under-examined dynamic requiring nuanced, reflexive analysis. Using a life course conceptual framing, this study explored age-related participant-researcher dynamics in interviews from two qualitative studies of older women’s sexual experiences in later life. Participants included 25 women whose ages ranged from 55 to 93 and both studies were completed by the same researcher, a relatively younger woman (age 23 and 28 at times of data collection). A thematic analysis revealed three primary themes: 1) taking care - participants took care of the researcher by offering advice, asking about the researcher’s life, and expressing hopes for a positive future, 2) expertise – varied expertise was demonstrated by the researcher (e.g. substantive and scholarly) and participants (e.g. life experience), and 3) researcher growth - the researcher’s interviewing tactics shifted between the two studies (e.g. use of validation rather than consolation in response to aging-related concerns), indicating a shift in perceptions of aging and later life. Findings indicate that older women participants and younger women researchers are bound together through the life course, by shared gendered experiences, the fact that one will eventually become the other, and the mutual sharing of expertise and caring. Gerontology researchers must actively reflect on the impact of their own identities and aging perceptions on the interviewing process in order to enhance rigor in qualitative research.

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.

Biogenesis of Magnetite Nanoparticles Using Shewanella Species Isolated from Diverse Regions

The objective of this study was to synthesize magnetite (Fe₃O₄) nanoparticles using diverse Shewanella species isolated from different environments. Magnetite formation experiments were performed with 11 species of Shewanella using akaganeite (β-FeOOH) as an electron acceptor and lactate (C₃H₆O₃) as an electron donor under a N₂ atmosphere at room temperature. Magnetites and other products formed by the bacteria were characterized by XRD and TEM-EDS analyses. In this study, all the strains of Shewanella species produced magnetite nanoparticles with 2.5 to 20 nm in size. However, the size of the magnetite varied with the species of Shewanella, and a few species formed Fe(III) oxide as secondary minerals such as goethite and lepidocrocite. These results indicate that different species of iron-reducing bacteria belonging to the genus Shewanella exhibit different rates of Fe(III) reduction resulting in magnetite nanocrystals of varying size and formation of secondary mineral species.

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.

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.

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.