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Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
Background: Traumatic brain injury (TBI) patients exhibit variable post-injury recovery trajectories. Days at Home (DAH) is a patient-centered measure that captures healthcare transitions and offers a more nuanced understanding of recovery. Here, we use DAH to characterize longterm recovery trajectories for moderate to severe TBI (msTBI) survivors. Methods: This multicenter retrospective cohort study utilized population health data from Ontario to identify adults sustaining isolated msTBI hospitalized between 2009-2021. DAH were calculated in distinct 30-day intervals from index admission to 3 years post-injury; latent class mixed modeling identified unique recovery trajectories and trajectory attributes were quantified. Results: There were 2,510 patients eligible for latent class analysis. Four DAH trajectories were identified: early recovery (69.9%), intermediate recovery (11.4%), late recovery (2.9%), and poor recovery (15.8%). Patients in the poor recovery group were older, more frail, and had lower admission GCS scores, while those in early recovery exhibited lower acute care needs. Intermediate and late recovery groups exhibited protracted transitions home, with near-complete reintegration by 24 months. A prediction model distinguished unfavorable trajectories with good accuracy (C-index=0.824). Conclusions: Despite high initial institutional care requirements, 85% of patients reintegrated into the community within three years of msTBI. These findings shed light on post-injury care requirements for brain-injured patients.
Rabbit farming is a form of low input agriculture that has potential to address food security and poverty in East Africa and beyond. For low input agriculture, farmers utilize local and affordable farm resources making it accessible across income levels. Understanding barriers and facilitators to rabbit farming could increase effectiveness of this form of low input agriculture in communities struggling with low food security and poverty, particularly for indigenous, smallholder farms. News media is an available source of data about community perceptions and practices on issues such as rabbit farming, food security, and poverty. For this qualitative study, researchers applied a priori and open coding text analysis to examine recurring themes in news media representations regarding perceptions of rabbit farming in East Africa. Results reveal that community members view rabbit farming as a community strategy that promotes better nutrition and food security while reducing poverty. Important themes included how gender and other cultural norms shaped efforts, and the role of sustainability and climate change on farming practices. Further, the easy cultivation of rabbits, funding, and protective policy and support of indigenous smallholder farms were perceived as facilitators for rabbit farming. Finally, investment in infrastructure for market, production, and knowledge-transfer of best production and business practices were considered critical to success for rabbit farmers throughout East Africa.
Globally, poor nutrition is a driver of many chronic diseases and is responsible for more deaths than any other risk factor. Accordingly, there is growing interest in the direct provision of healthy foods to patients to tackle diet-linked chronic diseases and mortality.
Aim:
To assess the effect of two healthy food interventions in conjunction with nutrition counseling and education on select chronic disease markers, food insecurity, diet quality, depression, and on self-efficacy for healthy eating, healthy weight, and chronic disease management.
Methods:
This parallel-arm quasi-randomized control trial will be conducted between January 2022 and December 2023. Seventy adult patients recruited from a single academic medical center will be randomly assigned to receive either: i) daily ready-made frozen healthy meals or ii) a weekly produce box and recipes for 15 weeks. Participants will, additionally, take part in one individual nutrition therapy session and watch videos on healthy eating, weight loss, type 2 diabetes, and hypertension. Data on weight, height, glycated hemoglobin, blood pressure, and diabetes and blood pressure medications will be collected in-person at the baseline visit and at 16 weeks from baseline and via medical chart review at six months and 12 months from enrollment. The primary outcome of the study is weight loss at 16 weeks from baseline. Pre- and post-intervention survey data will be analyzed for changes in food insecurity, diet quality, depression, as well as self-efficacy for health eating, healthy weight, and chronic disease management. Through retrospective chart review, patients who received standard of care will be matched to intervention group participants as controls based on body mass index, type 2 diabetes, and/or hypertension.
Findings:
By elucidating the healthy food intervention with better health outcomes, this study aims to offer evidence that can guide providers in their recommendations for healthy eating options to patients.
This article is a clinical guide which discusses the “state-of-the-art” usage of the classic monoamine oxidase inhibitor (MAOI) antidepressants (phenelzine, tranylcypromine, and isocarboxazid) in modern psychiatric practice. The guide is for all clinicians, including those who may not be experienced MAOI prescribers. It discusses indications, drug-drug interactions, side-effect management, and the safety of various augmentation strategies. There is a clear and broad consensus (more than 70 international expert endorsers), based on 6 decades of experience, for the recommendations herein exposited. They are based on empirical evidence and expert opinion—this guide is presented as a new specialist-consensus standard. The guide provides practical clinical advice, and is the basis for the rational use of these drugs, particularly because it improves and updates knowledge, and corrects the various misconceptions that have hitherto been prominent in the literature, partly due to insufficient knowledge of pharmacology. The guide suggests that MAOIs should always be considered in cases of treatment-resistant depression (including those melancholic in nature), and prior to electroconvulsive therapy—while taking into account of patient preference. In selected cases, they may be considered earlier in the treatment algorithm than has previously been customary, and should not be regarded as drugs of last resort; they may prove decisively effective when many other treatments have failed. The guide clarifies key points on the concomitant use of incorrectly proscribed drugs such as methylphenidate and some tricyclic antidepressants. It also illustrates the straightforward “bridging” methods that may be used to transition simply and safely from other antidepressants to MAOIs.
The Square Kilometre Array (SKA) will be the largest radio astronomy observatory ever built, providing unprecedented sensitivity over a very broad frequency band from 50 MHz to 15.3 GHz. The SKA’s low frequency component (SKA-Low), which will observe in the 50–350 MHz band, will be built at the Murchison Radio-astronomy Observatory (MRO) in Western Australia. It will consist of 512 stations each composed of 256 dual-polarised antennas, and the sensitivity of an individual station is pivotal to the performance of the entire SKA-Low telescope. The answer to the question in the title is, it depends. The sensitivity of a low frequency array, such as an SKA-Low station, depends strongly on the pointing direction of the digitally formed station beam and the local sidereal time (LST), and is different for the two orthogonal polarisations of the antennas. The accurate prediction of the SKA-Low sensitivity in an arbitrary direction in the sky is crucial for future observation planning. Here, we present a sensitivity calculator for the SKA-Low radio telescope, using a database of pre-computed sensitivity values for two realisations of an SKA-Low station architecture. One realisation uses the log-periodic antennas selected for SKA-Low. The second uses a known benchmark, in the form of the bowtie dipoles of the Murchison Widefield Array. Prototype stations of both types were deployed at the MRO in 2019, and since then have been collecting commissioning and verification data. These data were used to measure the sensitivity of the stations at several frequencies and over at least 24 h intervals, and were compared to the predictions described in this paper. The sensitivity values stored in the SQLite database were pre-computed for the X, Y, and Stokes I polarisations in 10 MHz frequency steps, $\scriptsize{1/2}$ hour LST intervals, and $5^\circ$ resolution in pointing directions. The database allows users to quickly and easily estimate the sensitivity of SKA-Low for arbitrary observing parameters (your favourite object) using interactive web-based or command line interfaces. The sensitivity can be calculated using publicly available web interface (http://sensitivity.skalow.link) or a command line python package (https://github.com/marcinsokolowski/station_beam), which can also be used to calculate the sensitivity for arbitrary pointing directions, frequencies, and times without interpolations.
Background: Obsessive compulsive disorder (OCD) and major depressive disorder (MDD) are common, often refractory, neuropsychiatric conditions for which new treatment approaches are urgently needed. Magnetic resonance guided focused ultrasound (MRgFUS) is a novel surgical technique permitting incisionless ablative neurosurgery. Methods: We examined the safety profile, clinical response, and imaging correlates of MRgFUS anterior capsulotomy (MRgFUS-AC) in patients with refractory OCD (n=7) and MDD (n = 10). Results: There were no serious adverse clinical or radiographic events. 5/7 OCD patients and 3/10 MDD patients met pre-established clinical response criteria. Neurocognitive performance improved on several measures of executive function (p<0.05). By 6 months, there were significant reductions in cerebral glucose metabolism, and reductions in the bilateral tracts connecting the thalamus with the orbitofrontal cortices, anterior cingulate cortex (p<0.05). Preoperative functional connectivity between the right ventral striatum and hippocampus was predictive of eventual clinical response (p-FDR<0.05). Conclusions: MRgFUS-AC is safe and demonstrates important evidence of efficacy in treatment resistant psychiatric disease, particularly OCD. The procedure was associated with structural and metabolic changes in brain networks implicated in affective regulation, Resting-state fMRI offers the ability to predict response, and potentially select patients most likely to improve.
El Niño cave, located on the south-eastern border of the Spanish Meseta, hosts a discontinuous sequence including Middle Palaeolithic and Neolithic levels, along with Upper Palaeolithic and Levantine style paintings. It is a key site for understanding human occupations of inland Iberia during the Palaeolithic and early prehistory. This paper summarises the main results of a multidisciplinary project aimed at defining the prehistoric human occupations at the site.
We present the first Southern-Hemisphere all-sky imager and radio-transient monitoring system implemented on two prototype stations of the low-frequency component of the Square Kilometre Array (SKA-Low). Since its deployment, the system has been used for real-time monitoring of the recorded commissioning data. Additionally, a transient searching algorithm has been executed on the resulting all-sky images. It uses a difference imaging technique to enable identification of a wide variety of transient classes, ranging from human-made radio-frequency interference to genuine astrophysical events. Observations at the frequency 159.375 MHz and higher in a single coarse channel ($\approx$0.926 MHz) were made with 2 s time resolution, and multiple nights were analysed generating thousands of images. Despite having modest sensitivity ($\sim$ few Jy beam–1), using a single coarse channel and 2-s imaging, the system was able to detect multiple bright transients from PSR B0950+08, proving that it can be used to detect bright transients of an astrophysical origin. The unusual, extreme activity of the pulsar PSR B0950+08 (maximum flux density $\sim$155 Jy beam–1) was initially detected in a ‘blind’ search in the 2020 April 10/11 data and later assigned to this specific pulsar. The limitations of our data, however, prevent us from making firm conclusions of the effect being due to a combination of refractive and diffractive scintillation or intrinsic emission mechanisms. The system can routinely collect data over many days without interruptions; the large amount of recorded data at 159.375 and 229.6875 MHz allowed us to determine a preliminary transient surface density upper limit of $1.32 \times 10^{-9} \text{deg}^{-2}$ for a timescale and limiting flux density of 2 s and 42 Jy, respectively. In the future, we plan to extend the observing bandwidth to tens of MHz and improve time resolution to tens of milliseconds in order to increase the sensitivity and enable detections of fast radio bursts below 300 MHz.
Mindfulness meditation has become a common method for reducing stress, stress-related psychopathology and some physical symptoms. As mindfulness programs become ubiquitous, concerns have been raised about their unknown potential for harm. We estimate multiple indices of harm following Mindfulness-Based Stress Reduction (MBSR) on two primary outcomes: global psychological and physical symptoms. In secondary analyses, we estimate multiple indices of harm on anxiety and depressive symptoms, discomfort in interpersonal relations, paranoid ideation and psychoticism.
Methods
Intent-to-treat analyses with multiple imputations for missing data were used on pre- and post-test data from a large, observational dataset (n = 2155) of community health clinic MBSR classes and from MBSR (n = 156) and waitlist control (n = 118) participants from three randomized controlled trials conducted contemporaneous to community classes in the same city by the same health clinic MBSR teachers. We estimate the change in symptoms, proportion of participants with increased symptoms, proportion of participants reporting greater than a 35% increase in symptoms, and for global psychological symptoms, clinically significant harm.
Results
We find no evidence that MBSR leads to higher rates of harm relative to waitlist control on any primary or secondary outcome. On many indices of harm across multiple outcomes, community MBSR was significantly preventative of harm.
Conclusions
Engagement in MBSR is not predictive of increased rates of harm relative to no treatment. Rather, MBSR may be protective against multiple indices of harm. Research characterizing the relatively small proportion of MBSR participants that experience harm remains important.
In numerical simulations of planetary dynamos there is an abrupt transition in the dynamics of both the velocity and magnetic fields at a‘local’ Rossby number of 0.1. For smaller Rossby numbers there are helical columnar structures aligned with the rotation axis, which efficiently maintain a dipolar field. However, when the thermal forcing is increased, these columns break down and the field becomes multi-polar. Similarly, in rotating turbulence experiments and simulations there is a sharp transition at a Rossby number of ${\sim}0.4$. Again, helical axial columnar structures are found for lower Rossby numbers, and there is strong evidence that these columns are created by inertial waves, at least on short time scales. We perform direct numerical simulations of the flow induced by a layer of buoyant anomalies subject to strong rotation, inspired by the equatorially biased heat flux in convective planetary dynamos. We assess the role of inertial waves in generating columnar structures. At high rotation rates (or weak forcing) we find columnar flow structures that segregate helicity either side of the buoyant layer, whose axial length scale increases linearly, as predicted by the theory of low-frequency inertial waves. As the rotation rate is weakened and the magnitude of the buoyant perturbations is increased, we identify a portion of the flow which is more strongly three-dimensional. We show that the flow in this region is turbulent, and has a Rossby number above a critical value $Ro^{crit}\sim 0.4$, consistent with previous findings in rotating turbulence. We suggest that the discrepancy between the transition value found here (and in rotating turbulence experiments), and that seen in the numerical dynamos ($Ro^{crit}\sim 0.1$), is a result of a different choice of the length scale used to define the local $Ro$. We show that when a proxy for the flow length scale perpendicular to the rotation axis is used in this definition, the numerical dynamo transition lies at $Ro^{crit}\sim 0.5$. Based on this we hypothesise that inertial waves, continually launched by buoyant anomalies, sustain the columnar structures in dynamo simulations, and that the transition documented in these simulations is due to the inability of inertial waves to propagate for $Ro>Ro^{crit}$.
In this study, monolingual (English) and bilingual (English/Spanish, English/Urdu) five- and six-year-old children completed a grammaticality judgment test in order to assess their awareness of the grammaticality of two types of syntactic constructions in English: word order and gender representation. All children were better at detecting grammatically correct and incorrect word order constructions than gender constructions, regardless of language group. In fact, bilingualism per se did not impact the results as much as receptive vocabulary range. For example, children with the highest receptive vocabulary scores were more accurate in detecting incorrect word order constructions (i.e., word order violations, semantic anomalies) and incorrect gender agreement than children in the lower receptive vocabulary ranges. However, no differences were found between the ranges for ambiguous gender constructions. These results highlight the importance of receptive vocabulary ability on syntactic awareness performance, regardless of language group.
Having discussed the basic theory and approaches to phased array receiver modeling, as well as figures of merit and system characterization, we now turn to specific details of the design and fabrication of the front end aperture itself. A wide variety of element types and configurations have been explored. Chief examples include the wideband sinuous element of the early explorations of PAFs at NRAO [1], dipole elements for PAFs [2], [3] as well as aperture arrays [4], tapered slot antennas or Vivaldi elements [5], [6], derivatives of the TSA element such as the egg-crate array, the checkerboard array [7]–[9] and other current-sheet implementations, horn elements [10], and of course the ubiquitous microstrip patch antenna [11] and the patch excited cup antenna designed by RUAG Space [12]. Many of these designs were surveyed in Chapter 1. In this chapter, we review considerations on selecting an appropriate element type, methods for design optimization, and fabrication issues. Receiver electronics is also discussed, with a specific focus on low noise amplifiers. Signal transport is also briefly addressed. The chapter concludes with an overview of downconversion and sampling, as well as the analog filters which these processes require.
Frequency and Bandwidth
Perhaps the most fundamental criteria in selecting an element type for a phased array system are the operating frequency and bandwidth. Frequency of operation might be considered the initial point in selecting an element, but because a given antenna type can be scaled, within fabrication limitations, to resonate or operate over a wide range of frequencies, bandwidth is in some ways the more critical driver. Element types can be divided most simply into narrowband, resonant antennas (dipole, patch) and wideband antennas (sinuous antenna, Vivaldi, checkerboard, and others). The division between narrowband and wideband is of course not a precise cutoff, but 10% to 20% relative bandwidth (i.e., bandwidth divided by the design center frequency), might be considered the upper limit of narrowband antenna types, and antennas with wider relative bandwidth would be considered to be wideband or ultrawideband. Bandwidth limitations are discussed further in Sec. 9.4.