Lactate as a key energy source facilitating cooperative behaviour in helper Damaraland mole-rats.

This study explores the metabolic factors that may aid in the division of labour in cooperatively breeding Damaraland mole-rat () colonies, particularly during digging activities. In these group-living mammals, both breeders and non-breeders participate in digging, among other cooperative tasks; however, non-breeding males and females (NBFs), often referred to as 'helpers', undertake this task at a higher frequency and engage in other energetically demanding activities more often than their breeding counterparts. We investigated how variation in glucose and lactate levels, two key energy substrates, relates to different levels of digging activity between breeders and non-breeders and how these metabolic patterns might underpin reproductive differences in activity and energy budgets.

Reduction of radiofrequency induced implant heating via flexible metasurface shielding at 7 T.

Passive implanted devices are commonly contraindicated at ultra-high field MRI due to the risk of radiofrequency heating. Mitigation of this risk has come in many forms, such as modifying implant materials or creating novel radiofrequency coils. These methods require substantial involvement from manufacturers and may not benefit patients with existing implants.

The road to a long lifespan in the Persian squirrel, a natural model for extended longevity: resisting free radical stress and healthy phospholipids.

Longevity is influenced by various factors, including fatty acid composition and free radical stress, which relate to the membrane pacemaker and rate of living hypotheses. While these aspects are well-documented in some long-lived species, they remain largely unexplored in tree squirrels. This study aimed to compare oxidative stress, antioxidant activity, nitrosative stress, and lipid composition between the long-lived Persian squirrel (Sciurus anomalus) and the short-lived Wistar rat across age cohorts (younger and older).

Identifying Coding Intensity in Medicare Advantage Through Switchers.

Objective: To estimate the extent of differential coding of health risk in traditional Medicare (TM) compared with Medicare Advantage (MA).

Study Setting And Design: Payments to MA plans are based on reported medical conditions, and research has shown the number and severity of diagnoses are larger when beneficiaries are enrolled in MA plans rather than TM. We compare the risk scores of Medicare beneficiaries who switch from TM into MA over the 2013-2021 period to the scores of beneficiaries who stay in TM, incorporating heterogeneous treatment effects across switching cohorts and over time.

Oxidative Stress in the Reproduction of Mammals.

Reproduction is a fundamental biological process, but it is also vulnerable to oxidative stress, which is a consequence of an imbalance between reactive oxygen species and antioxidant defences [...

In Vivo Brain B Inhomogeneity Correction and NOE Image Enhancement at 7 T via Flexible Metasurfaces.

Nuclear Overhauser effect (NOE) MRI has been used for in vivo brain imaging to assess lipid and protein composition and benefits from 7 T field strengths due to the larger chemical shift dispersion. However, a continuing challenge is signal drop off observed in regions such as the medial temporal lobes due to "standing wave" effects from shorter radiofrequency (RF) wavelengths at ultra-high fields. 2D periodic unit cell metasurfaces have been a promising approach for providing improvements in anatomical imaging but have not yet been evaluated in chemical exchange saturation transfer (CEST)-based sequences.

Diffuse nuclear Overhauser effect MRI contrast changes detected in multiple sclerosis subjects at 7T.

Multiple sclerosis is an inflammatory demyelinating condition of the central nervous system affecting approximately 1 million people in the USA. Although standard structural MRI techniques are now the main imaging modality for multiple sclerosis diagnosis and management, they are yet to provide information regarding the metabolic profile of the disease. Ultra-high field 7T MRI systems have provided gains in signal-to-noise ratio (SNR) and spatial resolution for structural MRI as well as larger chemical shifts leading to improvements in specialized imaging sequences, such as nuclear Overhauser effect (NOE) imaging, that can evaluate macromolecular metabolite composition.

Assessing multiple MRI sequences in deep learning-based synthetic CT generation for MR-only radiation therapy of head and neck cancers.

Purpose: This study investigated the effect of multiple magnetic resonance (MR) sequences on the quality of deep-learning-based synthetic computed tomography (sCT) generation in the head and neck region.

Materials And Methods: 12 MR series (T1pre-, T1post-contrast, T2 each with 4 Dixon images) were collected from 26 patients with head and neck cancers. 14 unique deep-learning models using the U-Net framework were trained using multiple MRs as inputs to generate sCTs.

Changes in coverage stability and churning for private, individual insurance under the Affordable Care Act.

The Affordable Care Act (ACA) transformed the market for individual insurance. Using the 2-year panels of the Household Component of the Medical Expenditure Panel Survey covering the 2002-2022 period and controlling for the business cycle and other factors, we find the share of nonelderly adults enrolled in individual insurance doubled under the ACA. The percentage of adults covered by individual insurance 1-23 months more than doubled, and the percentage with at least 24 months rose 80% in states that did not expand Medicaid.

Oxidative Stress in an African Ground Squirrel, a Case of Healthy Aging and Reproduction.

Oxidative stress plays a crucial role in mediating life-history processes, where it can compromise survival and reproduction through harmful alterations to DNA, lipids, and proteins. In this study, we investigated oxidative stress in Cape ground squirrels (), a longer-lived African ground squirrel species with a high reproductive skew and unique life history strategies. We measured oxidative stress as total antioxidant capacity (TAC), total oxidant status (TOS), and an oxidative stress index (OSI) in blood plasma from individuals of approximately known ages.

Newly and Previously Eligible Medicaid Enrollees Differ, but Not in Health Care Expenditures.

In 2014, the Affordable Care Act (ACA) expanded the role of Medicaid by encouraging states to increase eligibility for lower-income adults. As of 2024, 10 states had not adopted the expanded eligibility provisions of the ACA, possibly due to concerns about the state's share of spending. Using the Medical Expenditure Panel Survey (MEPS), we documented how health care utilization, expenditures, and the overall health status of newly eligible enrollees compare with enrollees who would have been eligible under their states' rules before the ACA.

Acute nicotinamide riboside supplementation increases human cerebral NAD levels in vivo.

Purpose: The purpose of this study was to determine the effect of acute nicotinamide riboside (NR) supplementation on cerebral nicotinamide adenine dinucleotide (NAD) levels in the human brain in vivo by means of downfield proton MRS (DF H MRS).

Methods: DF H MRS was performed on 10 healthy volunteers in a 7.0 T MRI scanner with spectrally selective excitation and spatially selective localization to determine cerebral NAD levels on two back-to-back days: once after an overnight fast (baseline) and once 4 h after oral ingestion of nicotinamide riboside (900 mg).

In-Home Health Risk Assessments And Chart Reviews Contribute To Coding Intensity In Medicare Advantage.

There is widespread agreement that taxpayers pay more when Medicare beneficiaries are enrolled in Medicare Advantage (MA) plans than if those beneficiaries were enrolled in traditional Medicare. MA plans are paid on the basis of submitted diagnoses and thus have a clear incentive to encourage providers to find and report as many diagnoses for their enrollees as possible. Two mechanisms that MA plans use to identify diagnoses that are not available for beneficiaries in traditional Medicare are in-home health risk assessments and chart reviews.

Personalized and muscle-specific OXPHOS measurement with integrated CrCEST MRI and proton MR spectroscopy.

Creatine chemical exchange saturation transfer (CrCEST) MRI is an emerging high resolution and noninvasive method for measuring muscle specific oxidative phosphorylation (OXPHOS). However, CrCEST measurements are sensitive to changes in muscle pH, which might confound the measurement and interpretation of creatine recovery time (τ). Even with the same prescribed exercise stimulus, the extent of acidification and hence its impact on τ is expected to vary between individuals.

Horizontal and vertical equity and public subsidies for private health insurance in the U.S.

The United States offers two markedly different subsidy structures for private health insurance. When covered through employer-based plans, employees and their dependents benefit from the exclusion from taxable income of the premiums. Individuals without access to employer coverage may obtain subsidies for Marketplace coverage.

In vivo enhancement of calf MRI at 7 T via optimized flexible metasurfaces.

Purpose: Ultrahigh field (≥7 T) MRI is at the cutting edge of medical imaging, enabling enhanced spatial and spectral resolution as well as enhanced susceptibility contrast. However, transmit ( ) field inhomogeneity due to standing wave effects caused by the shortened RF wavelengths at 7 T is still a challenge to overcome. Novel hardware methods such as dielectric pads have been shown to improve the field inhomogeneity but are currently limited in their corrective effect by the range of high-permittivity materials available and have a fixed shelf life.

The role of ambient temperature and light as cues in the control of circadian rhythms of Damaraland mole-rat.

Light is considered the primary entrainer for mammalian biological rhythms, including locomotor activity (LA). However, mammals experience different environmental and light conditions, which include those predominantly devoid of light stimuli, such as those experienced in subterranean environments. In this study, we investigated what environmental cue (light or ambient temperature (T)) is the strongest modulator of circadian rhythms, by using LA as a proxy, in mammals that experience a lifestyle devoid of light stimuli.

Application of glutamate weighted CEST in brain imaging of nicotine dependent participants in vivo at 7T.

Introduction: With nicotine dependence being a significant healthcare issue worldwide there is a growing interest in developing novel therapies and diagnostic aids to assist in treating nicotine addiction. Glutamate (Glu) plays an important role in cognitive function regulation in a wide range of conditions including traumatic brain injury, aging, and addiction. Chemical exchange saturation transfer (CEST) imaging via ultra-high field MRI can image the exchange of certain saturated labile protons with the surrounding bulk water pool, making the technique a novel tool to investigate glutamate in the context of addiction.

A review of recent developments and applications of high-permittivity dielectric shimming in magnetic resonance.

We present a review outlining the basic mechanism, background, recent technical developments, and clinical applications of aqueous dielectric padding in the field of MRI. Originally meant to be a temporary solution, it has gained traction as an effective method for correcting B inhomogeneities due to the unique properties of the calcium titanate and barium titanate perovskites used. Aqueous dielectric pads have used a variety of high-permittivity materials over the years to improve the quality of MRI acquisitions at 1.

The effect of frequency (64-498 MHz) on specific absorption rate adjacent to metallic orthopedic screws in MRI: A numerical simulation study.

Background: The imaging of patients with implanted electrically-conductive devices via magnetic resonance imaging at ultra-high fields is hampered by uncertainties relating to the potential for inducing tissue heating adjacent to the implant due to coupling of energy from the incident electromagnetic field into the implant. Existing data in the peer-reviewed literature of comparisons across field strengths of tissue heating and its surrogate, the specific absorption rate (SAR), is scarce and contradictory, leading to further doubts pertaining to the safety of imaging patients with such devices.

Purpose: The radiofrequency-induced SAR adjacent to orthopedic screws of varying length and at frequencies of 64 to 498 MHz was investigated via full-wave electromagnetic simulations, to provide an accurate comparison of SAR across MRI field strengths.

The Evolution and Ecology of Oxidative and Antioxidant Status: A Comparative Approach in African Mole-Rats.

The naked mole-rat of the family Bathyergidae has been the showpiece for ageing research as they contradict the traditional understanding of the oxidative stress theory of ageing. Some other bathyergids also possess increased lifespans, but there has been a remarkable lack of comparison between species within the family Bathyergidae. This study set out to investigate how plasma oxidative markers (total oxidant status (TOS), total antioxidant capacity (TAC), and the oxidative stress index (OSI)) differ between five species and three subspecies of bathyergids, differing in their maximum lifespan potential (MLSP), resting metabolic rate, aridity index (AI), and sociality.

Systematic Evaluation of the Impact of Lung Segmentation Methods on 4-Dimensional Computed Tomography Ventilation Imaging Using a Large Patient Database.

Purpose: A novel form of lung functional imaging applied for functional avoidance radiation therapy has been developed that uses 4-dimensional computed tomography (4DCT) data and image processing techniques to calculate lung ventilation (4DCT-ventilation). Lung segmentation is a common step to define a region of interest for 4DCT-ventilation generation. The purpose of this study was to quantitatively evaluate the sensitivity of 4DCT-ventilation imaging using different lung segmentation methods.