Improved receiver noise calibration for ADMX axion search: 4.54 to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mn>5.41</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>μeV</mml:mi></mml:mrow></mml:math>

Physical review. D/Physical review. D. · 2025-05-20 · 2 citations

Axions are a well-motivated candidate for dark matter. The preeminent method to search for axion dark matter is known as the axion haloscope, which makes use of the conversion of axions to photons in a large magnetic field. Because of the weak coupling of axions to photons, however, the expected signal strength is exceptionally small. To increase signal strength, many haloscopes make use of resonant enhancement and high gain amplifiers, while also taking measures to keep receiver noise as low as possible such as the use of dilution refrigerators and ultra-low-noise electronics. In this paper, we derive the theoretical noise model based on the sources of noise found within a typical axion haloscope receiver chain, using the Axion Dark Matter eXperiment (ADMX) as a case study. We present examples of different noise calibration measurements at 1280 MHz taken during ADMX’s most recent data-taking run. These new results shed light on a previously unidentified interaction between the cavity and Josephson Parametric Amplifier as well as provide a better understanding of the systematic uncertainty on the system noise temperature used in the axion search analysis for this data-taking run. Finally, the consistency between the measurements and the detailed model provide suggestions for future improvements within ADMX and other axion haloscopes to reach a lower noise temperature.

Search for non-virialized axions with 3.3-4.2 $μ$eV mass at selected resolving powers

arXiv (Cornell University) · 2024-10-11

The Axion Dark Matter eXperiment is sensitive to narrow axion flows, given axions compose a fraction of the dark matter with a non-negligible local density. Detecting these low-velocity dispersion flows requires a high spectral resolution and careful attention to the expected signal modulation due to Earth's motion. We report an exclusion on the local axion dark matter density in narrow flows of $ρ_a \gtrsim 0.03\,\mathrm{GeV/cm^3}$ and $ρ_a \gtrsim 0.004\,\mathrm{GeV/cm^3}$ for Dine-Fischler-Srednicki-Zhitnitski and Kim-Shifman-Vainshtein-Zakharov axion-photon couplings, respectively, over the mass range $3.3-4.2\,μ\text{eV}$. Measurements were made at selected resolving powers to allow for a range of possible velocity dispersions.

Vocal and tongue exercise in early to mid-stage Parkinson disease using the Pink1-/- rat

Brain Research · 2024-04-27 · 4 citations

Nonvirialized axion search sensitive to Doppler effects in the Milky Way halo

Physical review. D/Physical review. D. · 2024-04-10 · 5 citations

The Axion Dark Matter eXperiment (ADMX) has previously excluded Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions between 680--790 MHz under the assumption that the dark matter is described by the isothermal halo model. However, the precise nature of the velocity distribution of dark matter is still unknown, and alternative models have been proposed. We report the results of a nonvirialized axion search over the mass range $2.81--3.31\text{ }\text{ }\mathrm{\ensuremath{\mu}}\mathrm{eV}$, corresponding to the frequency range 680--800 MHz. This analysis marks the most sensitive search for nonvirialized axions sensitive to Doppler effects in the Milky Way Halo to date. Accounting for frequency shifts due to the detector's motion through the Galaxy, we exclude cold flow relic axions with a velocity dispersion of $\mathcal{O}({10}^{\ensuremath{-}7})\mathrm{c}$ with 95% confidence.

Early ultrasonic vocalization deficits and related thyroarytenoid muscle pathology in the transgenic TgF344-AD rat model of Alzheimer’s disease

Frontiers in Behavioral Neuroscience · 2024-01-23 · 7 citations

Background Alzheimer’s disease (AD) is a progressive neurologic disease and the most common cause of dementia. Classic pathology in AD is characterized by inflammation, abnormal presence of tau protein, and aggregation of β-amyloid that disrupt normal neuronal function and lead to cell death. Deficits in communication also occur during disease progression and significantly reduce health, well-being, and quality of life. Because clinical diagnosis occurs in the mid-stage of the disease, characterizing the prodrome and early stages in humans is currently challenging. To overcome these challenges, we use the validated TgF344-AD (F344-Tg(Prp-APP, Prp-PS1)19/Rrrc) transgenic rat model that manifests cognitive, behavioral, and neuropathological dysfunction akin to AD in humans. Objectives The overarching goal of our work is to test the central hypothesis that pathology and related behavioral deficits such as communication dysfunction in part manifest in the peripheral nervous system and corresponding target tissues already in the early stages. The primary aims of this study are to test the hypotheses that: (1) changes in ultrasonic vocalizations (USV) occur in the prodromal stage at 6 months of age and worsen at 9 months of age, (2) inflammation as well as AD-related pathology can be found in the thyroarytenoid muscle (TA) at 12 months of age (experimental endpoint tissue harvest), and to (3) demonstrate that the TgF344-AD rat model is an appropriate model for preclinical investigations of early AD-related vocal deficits. Methods USVs were collected from male TgF344-AD ( N = 19) and wildtype (WT) Fischer-344 rats ( N = 19) at 6 months ( N = 38; WT: n = 19; TgF344-AD : n = 19) and 9 months of age ( N = 18; WT: n = 10; TgF344-AD : n = 8) and acoustically analyzed for duration, mean power, principal frequency, low frequency, high frequency, peak frequency, and call type. RT-qPCR was used to assay peripheral inflammation and AD-related pathology via gene expressions in the TA muscle of male TgF344-AD rats ( n = 6) and WT rats ( n = 6) at 12 months of age. Results This study revealed a significant reduction in mean power of ultrasonic calls from 6 to 9 months of age and increased peak frequency levels over time in TgF344-AD rats compared to WT controls. Additionally, significant downregulation of AD-related genes Uqcrc2 , Bace2 , Serpina3n , and Igf2, as well as downregulation of pro-inflammatory gene Myd88 was found in the TA muscle of TgF344-AD rats at 12 months of age. Discussion Our findings demonstrate early and progressive vocal deficits in the TgF344-AD rat model. We further provide evidence of dysregulation of AD-pathology-related genes as well as inflammatory genes in the TA muscles of TgF344-AD rats in the early stage of the disease, confirming this rat model for early-stage investigations of voice deficits and related pathology.

Effects of chemoradiation and tongue exercise on swallow biomechanics and bolus kinematics

Head & Neck · 2024-08-16 · 3 citations

BACKGROUND: Common treatments for head and neck cancer (radiation and chemotherapy) can lead to dysphagia; tongue exercise is a common intervention. This study aimed to assess swallow biomechanics and bolus kinematics using a well-established rat model of radiation or chemoradiation treatment to the tongue base, with or without tongue exercise intervention. METHODS: Pre- and post-treatment videofluoroscopy was conducted on 32 male Sprague-Dawley rats treated with radiation/chemoradiation and exercise/no exercise. Rats in the exercise groups completed a progressive resistance tongue training paradigm. Swallow biomechanics, bolus kinematics, jaw opening, and post-swallow respiration were assessed. RESULTS: Both treatments impacted outcome measures; the addition of exercise intervention showed benefit for some measures, particularly in rats treated with radiation, vs. chemoradiation. CONCLUSIONS: Radiation and chemoradiation can significantly affect aspects of deglutition; combined treatment may result in worse outcomes. Tongue exercise intervention can mitigate deficits; more intensive intervention may be warranted in proportion to combined treatment.

Altered tongue muscle contractile properties coincide with altered swallow function in the adult Ts65Dn mouse model of down syndrome

Frontiers in Neurology · 2024-03-22 · 3 citations

Purpose: Down syndrome (DS) is a developmental disability associated with difficulties in deglutition. The adult Ts65Dn mouse model of DS has been previously shown to have differences in measures of swallowing compared with euploid controls. However, the putative mechanisms of these differences in swallowing function are unclear. This study tested the hypothesis that the Ts65Dn genotype is associated with atypical measures of tongue muscle contractile properties, coinciding with atypical swallow function. Methods: = 16 female, 14 male) were evaluated through videofluoroscopy swallow studies (VFSS) to quantify measures of swallowing performance including swallow rate and inter-swallow interval (ISI). After VFSS, retrusive tongue muscle contractile properties, including measures of muscle fatigue, were determined using bilateral hypoglossal nerve stimulation. Results: The Ts65Dn group had significantly slower swallow rates, significantly greater ISI times, significantly slower rates of tongue force development, and significantly greater levels of tongue muscle fatigue, with lower retrusive tongue forces than controls in fatigue conditions. Conclusion: Tongue muscle contractile properties are altered in adult Ts65Dn and coincide with altered swallow function.

Improved Receiver Noise Calibration for ADMX Axion Search: 4.54 to 5.41 $μ$eV

arXiv (Cornell University) · 2024-11-11

Axions are a well-motivated candidate for dark matter. The preeminent method to search for axion dark matter is known as the axion haloscope, which makes use of the conversion of axions to photons in a large magnetic field. Due to the weak coupling of axions to photons however, the expected signal strength is exceptionally small. To increase signal strength, many haloscopes make use of resonant enhancement and high gain amplifiers, while also taking measures to keep receiver noise as low as possible such as the use of dilution refrigerators and ultra low-noise electronics. In this paper we derive the theoretical noise model based on the sources of noise found within a typical axion haloscope receiver chain, using the Axion Dark Matter eXperiment (ADMX) as a case study. We present examples of different noise calibration measurements at 1280~MHz using a variable temperature stage with ADMX during its most recent data taking run. The consistency between the measurements and the detailed model provide suggestions for future improvements within ADMX and other axion haloscopes to reach a lower noise temperature and to simplify the receiver chain design.

Tongue and laryngeal exercises improve tongue strength and vocal function outcomes in a Pink1-/- rat model of early Parkinson disease

Behavioural Brain Research · 2023-11-20 · 5 citations

Comprehensive management of anterior drooling: An International Pediatric Otolaryngology Group (IPOG) consensus statement

International Journal of Pediatric Otorhinolaryngology · 2023-03-09 · 13 citations