Evaluation of an integrated variable flip angle protocol to estimate coil B for hyperpolarized MRI.

Purpose: The purpose of this work is to validate a simple and versatile integrated variable flip angle (VFA) method for mapping B in hyperpolarized MRI, which can be used to correct signal variations due to coil inhomogeneity.

Theory And Methods: Simulations were run to assess performance of the VFA B mapping method compared to the currently used constant flip angle (CFA) approach. Simulation results were used to inform the design of VFA sequences, validated in four volunteers for hyperpolarized xenon-129 imaging of the lungs and another four volunteers for hyperpolarized carbon-13 imaging of the human brain.

Regional fire-greening positive feedback loops in Alaskan Arctic tundra.

Arctic tundra has experienced rapid warming, outpacing global averages, leading to significant greening whose primary drivers include widespread shrubification. Here we confirm that a fire-greening positive feedback loop is evident across the Alaskan tundra, and evidence suggests that this feedback loop is dominated by the fire-shrub interactions. We show that tundra wildfires, especially those with higher severity, play a critical role in boosting the overall greening of the tundra, often by enhancing upright deciduous shrub growth or establishment but sometimes by inducing increases in other vascular biomass.

Warming and disturbances affect Arctic-boreal vegetation resilience across northwestern North America.

Rapid warming and increasing disturbances in high-latitude regions have caused extensive vegetation shifts and uncertainty in future carbon budgets. Better predictions of vegetation dynamics and functions require characterizing resilience, which indicates the capability of an ecosystem to recover from perturbations. Here, using temporal autocorrelation of remotely sensed greenness, we quantify time-varying vegetation resilience during 2000-2019 across northwestern North American Arctic-boreal ecosystems.

Genetic diversity of in sub-Saharan Africa: a two-marker genotyping approach for molecular epidemiological studies.

Introduction: is the most common non-falciparum species in sub-Saharan Africa. Despite this, data on its genetic diversity is scarce. Therefore, we aimed to establish a genotyping approach based on size polymorphic regions that can be easily applied in molecular epidemiological studies.

Pixel walking along the boreal forest-Arctic tundra ecotone: Large scale ground-truthing of satellite-derived greenness (NDVI).

In this Technical Advance, we describe a novel method to improve ecological interpretation of remotely sensed vegetation greenness measurements that involved sampling 24,395 Landsat pixels (30 m) across 639 km of Alaska's central Brooks Range. The method goes well beyond the spatial scale of traditional plot-based sampling and thereby more thoroughly relates ground-based observations to satellite measurements. Our example dataset illustrates that, along the boreal-Arctic boundary, vegetation with the greatest Landsat Normalized Difference Vegetation Index (NDVI) is taller than 1 m, woody, and deciduous; whereas vegetation with lower NDVI tends to be shorter, evergreen, or non-woody.

Evaluating the predictions of an interoceptive inference model of bulimia nervosa.

Objective: Bulimia nervosa (BN) is associated with loss-of-control (LOC) eating episodes that frequently occur in response to negative emotions. According to recent neurocomputational models, this link could be explained by a failure to accurately update beliefs about the body in states of high arousal. Specifically, these interoceptive inference models suggest that under-relying on signals from one's body about sensory experience ("low sensory precision") and/or over-relying on previously held beliefs ("excessively precise priors") lead to inaccurate perception and maladaptive behaviors.

Upscaling vascular aboveground biomass and topsoil moisture of subarctic fens from Unoccupied Aerial Vehicles (UAVs) to satellite level.

Arctic and subarctic ecosystems are experiencing rapid changes in vegetation composition and productivity due to global warming. Tundra wetlands are especially susceptible to these changes, which may trigger shifts in soil moisture dynamics. It is therefore essential to accurately map plant biomass and topsoil moisture.

The Arctic Plant Aboveground Biomass Synthesis Dataset.

Plant biomass is a fundamental ecosystem attribute that is sensitive to rapid climatic changes occurring in the Arctic. Nevertheless, measuring plant biomass in the Arctic is logistically challenging and resource intensive. Lack of accessible field data hinders efforts to understand the amount, composition, distribution, and changes in plant biomass in these northern ecosystems.

Distinct Topological Properties of the Reward Anticipation Network in Preadolescent Children With Binge Eating Disorder Symptoms.

Objective: Few studies have considered the neural underpinnings of binge eating disorder (BED) in children, despite clinical and subclinical symptom presentation occurring in this age group. Symptom presentation at this age is of clinical relevance, as early onset of binge eating is linked to negative health outcomes. Studies in adults have highlighted dysfunction in the frontostriatal reward system as a potential candidate for binge eating pathophysiology, although the exact nature of such dysfunction is currently unclear.

Forest composition change and biophysical climate feedbacks across boreal North America.

Deciduous tree cover is expected to increase in North American boreal forests with climate warming and wildfire. This shift in composition has the potential to generate biophysical cooling via increased land surface albedo. Here we use Landsat-derived maps of continuous tree canopy cover and deciduous fractional composition to assess albedo change over recent decades.

Effects of borderline personality disorder symptoms on dialectical behavior therapy outcomes for eating disorders.

Existing literature on the effects of borderline personality disorder (BPD) and eating disorder (ED) comorbidity in terms of clinical presentation and treatment outcome has been limited and inconclusive. The present study examined whether clients with EDs and varying levels of BPD symptoms presented with more severe ED symptoms at admission, and whether they responded to dialectical behavior therapy (DBT)-based treatment. Participants ( = 176) were adults in a DBT-based partial hospitalization program for EDs at an academic medical center.

Time-of-day and day-of-week patterns of binge eating and relevant psychological vulnerabilities in binge-eating disorder.

Objective: The present study sought to characterize the temporal patterns of binge eating and theorized maintenance factors among individuals with binge-eating disorder (BED).

Method: Ecological momentary assessment of 112 individuals and mixed-effects models were used to characterize the within- and between-day temporal patterns of eating behaviors (binge eating, loss of control only eating, and overeating only), positive and negative affect, emotion regulation difficulty, and food craving.

Results: Risk for binge eating and overeating only was highest around 5:30 p.

Whole genome analysis of two sympatric human : and sp "DEUX".

Introduction: species are filarial parasites that infect humans worldwide. Although these infections are common, knowledge of the pathology and diversity of the causative species is limited. Furthermore, the lack of sequencing data for species, shows that their research is neglected.

State-specific alterations in the neural computations underlying inhibitory control in women remitted from bulimia nervosa.

The neurocomputational processes underlying bulimia nervosa and its primary symptoms, out-of-control overeating and purging, are poorly understood. Research suggests that the brains of healthy individuals form a dynamic internal model to predict whether control is needed in each moment. This study tested the hypothesis that this computational process of inhibitory control is abnormally affected by metabolic state (being fasted or fed) in bulimia nervosa.

targeting and multimodal imaging of cerebral amyloid-β aggregates using hybrid GdF nanoparticles.

To propose a new multimodal imaging agent targeting amyloid-β (Aβ) plaques in Alzheimer's disease. A new generation of hybrid contrast agents, based on gadolinium fluoride nanoparticles grafted with a pentameric luminescent-conjugated polythiophene, was designed, extensively characterized and evaluated in animal models of Alzheimer's disease through MRI, two-photon microscopy and synchrotron x-ray phase-contrast imaging. Two different grafting densities of luminescent-conjugated polythiophene were achieved while preserving colloidal stability and fluorescent properties, and without affecting biodistribution.

Computational models of behavioral addictions: State of the art and future directions.

Non-pharmacological behavioral addictions, such as pathological gambling, videogaming, social networking, or internet use, are becoming major public health concerns. It is not yet clear how behavioral addictions could share many major neurobiological and behavioral characteristics with substance use disorders, despite the absence of direct pharmacological influences. A deeper understanding of the neurocognitive mechanisms of addictive behavior is needed, and computational modeling could be one promising approach to explain intricately entwined cognitive and neural dynamics.

Impaired belief updating and devaluation in adult women with bulimia nervosa.

Recent models of bulimia nervosa (BN) propose that binge-purge episodes ultimately become automatic in response to cues and insensitive to negative outcomes. Here, we examined whether women with BN show alterations in instrumental learning and devaluation sensitivity using traditional and computational modeling analyses of behavioral data. Adult women with BN (n = 30) and group-matched healthy controls (n = 31) completed a task in which they first learned stimulus-response-outcome associations.

Soil moisture impacts the tundra carbon balance in a changing climate.

There is growing recognition that soil moisture plays a crucial role in regulating the response of tundra carbon cycling to climate warming.

[Life-threatening complication caused by a neurostimulator].

We report on a 66-year-old neuro-urological female patient who, three years after implantation of a neurostimulator, experienced cecal necrosis due to strangulation caused by the cable of the device.

Brain Structure in Acutely Underweight and Partially Weight-Restored Individuals With Anorexia Nervosa: A Coordinated Analysis by the ENIGMA Eating Disorders Working Group.

Background: The pattern of structural brain abnormalities in anorexia nervosa (AN) is still not well understood. While several studies report substantial deficits in gray matter volume and cortical thickness in acutely underweight patients, others find no differences, or even increases in patients compared with healthy control subjects. Recent weight regain before scanning may explain some of this heterogeneity.

Response to letter to the editor on "Satellite observations document trends consistent with a boreal biome shift".

Here we response to a Letter to the Editor by Timoney (2022) and maintain our conclusion that "there have been systematic trends in vegetation greenness during recent decades that are consistent with an emerging boreal biome shift associated with ongoing climate warming."

An Interpretable and Predictive Connectivity-Based Neural Signature for Chronic Cannabis Use.

Background: Cannabis is one of the most widely used substances in the world, with usage trending upward in recent years. However, although the psychiatric burden associated with maladaptive cannabis use has been well established, reliable and interpretable biomarkers associated with chronic use remain elusive. In this study, we combine large-scale functional magnetic resonance imaging with machine learning and network analysis and develop an interpretable decoding model that offers both accurate prediction and novel insights into chronic cannabis use.