Altered white matter microstructural organization in posttraumatic stress disorder across 3047 adults: results from the PGC-ENIGMA PTSD consortium

A growing number of studies have examined alterations in white matter organization in people with posttraumatic stress disorder (PTSD) using diffusion MRI (dMRI), but the results have been mixed which may be partially due to relatively small sample sizes among studies. Altered structural connectivity may be both a neurobiological vulnerability for, and a result of, PTSD. In an effort to find reliable effects, we present a multi-cohort analysis of dMRI metrics across 3047 individuals from 28 cohorts currently participating in the PGC-ENIGMA PTSD working group (a joint partnership between the Psychiatric Genomics Consortium and the Enhancing NeuroImaging Genetics through Meta-Analysis consortium). Comparing regional white matter metrics across the full brain in 1426 individuals with PTSD and 1621 controls (2174 males/873 females) between ages 18-83, 92% of whom were trauma-exposed, we report associations between PTSD and disrupted white matter organization measured by lower fractional anisotropy (FA) in the tapetum region of the corpus callosum (Cohen's d = -0.11, p = 0.0055). The tapetum connects the left and right hippocampus, for which structure and function have been consistently implicated in PTSD. Results were consistent even after accounting for the effects of multiple potentially confounding variables: childhood trauma exposure, comorbid depression, history of traumatic brain injury, current alcohol abuse or dependence, and current use of psychotropic medications. Our results show that PTSD may be associated with alterations in the broader hippocampal network.New methods for child psychiatric diagnosis and treatment outcome evaluatio

Neuroimaging-based classification of PTSD using data-driven computational approaches: a multisite big data study from the ENIGMA-PGC PTSD consortium

Background: Recent advances in data-driven computational approaches have been helpful in devising tools to objectively diagnose psychiatric disorders. However, current machine learning studies limited to small homogeneous samples, different methodologies, and different imaging collection protocols, limit the ability to directly compare and generalize their results. Here we aimed to classify individuals with PTSD versus controls and assess the generalizability using a large heterogeneous brain datasets from the ENIGMA-PGC PTSD Working group. Methods: We analyzed brain MRI data from 3,477 structural-MRI; 2,495 resting state-fMRI; and 1,952 diffusion-MRI. First, we identified the brain features that best distinguish individuals with PTSD from controls using traditional machine learning methods. Second, we assessed the utility of the denoising variational autoencoder (DVAE) and evaluated its classification performance. Third, we assessed the generalizability and reproducibility of both models using leave-one-site-out cross-validation procedure for each modality. Results: We found lower performance in classifying PTSD vs. controls with data from over 20 sites (60 % test AUC for s-MRI, 59 % for rs-fMRI and 56 % for D-MRI), as compared to other studies run on single-site data. The performance increased when classifying PTSD from HC without trauma history in each modality (75 % AUC). The classification performance remained intact when applying the DVAE framework, which reduced the number of features. Finally, we found that the DVAE framework achieved better generalization to unseen datasets compared with the traditional machine learning frameworks, albeit performance was slightly above chance. Conclusion: These results have the potential to provide a baseline classification performance for PTSD when using large scale neuroimaging datasets. Our findings show that the control group used can heavily affect classification performance. The DVAE framework provided better generalizability for the multi-site data. This may be more significant in clinical practice since the neuroimaging-based diagnostic DVAE classification models are much less site-specific, rendering them more generalizable.Stress-related psychiatric disorders across the life spa

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

Evaluation of aflatoxin B1 in different parts of pistachio fruit and effects of processing stages

Pistachio nut as the most important agricultural export products is facing challenges trough production and conception. Toxigenic Aspergillus species are able to grow and produce dangerous mycotoxins on pistachio nut. Distribution of aflatoxin in different pistachio samples collected pre- (early splitting and healthy pistachios in orchards) and post-harvest (steps in processing plants) was evaluated. Aflatoxin B1 content of samples was quantified using ELISA.  Overall, high content of aflatoxin B1 in pre-harvest was observed in early splitting pistachios which were 5 times higher than healthy ones. The mean value of aflatoxin B1 content in early splitting and healthy pistachio was 10.2 and 1.8 ng/g, respectively. In processing plant, the content of aflatoxin B1 in stained, small, floater and open shell pistachios was 21, 4, 15 and 2 times higher than unstained, large, sinker and closed shell pistachios, respectively. The presence of aflatoxin B1 in samples taken from orchards and processing plants indicates pre-harvest contamination by aflatoxin-producing fungi, which may exacerbate by inadequate post-harvest conditions. Physical properties of contaminated pistachios may be used to reduce aflatoxin levels in pistachio bulks during or after processing. ELISA, as practical, sensitive and cheap method, may apply to determine the aflatoxin content of pistachios

Status of alfalfa witches’ broom phytoplasma disease in Iran

Alfalfa witches’ broom (AWB) is one of the most important and destructive diseases of alfalfa in Iran. Based on characteristic disease symptoms and direct and nested polymerase chain reactions, the status of AWB disease was evaluated in different growing areas of Iran. Restriction fragment length polymorphism was used to identify AWB disease associated phytoplasmas. Furthermore, infection rate, disease severity, death rate of infected plant in the summer and winter and overwintering of disease vector were assessed. Based on the results, AWB disease was reported on different alfalfa cultivars in Yazd, Fars, Sistan-Va-Baluchestan, Kerman, Hormozgan, Bushehr, Esfahan, Chaharmahal-Va-Bakthiari, South Khorasan and Khuzestan provinces of Iran. Phytoplasmas associated with AWB in these areas were identified as ‘Candidatus Phytoplasma aurantifolia’, belonging to peanut witches’ broom (16SrII) group. In Abarkooh and Ashkezar (Yazd province) and Bondarooz (Bushehr province) the recorded disease incidence was up to 100%. The highest disease severity was found in Rezvan Shahr (Ashkezar, Yazd province) in 3 years old alfalfa fields. The highest death rate of infected plants in summer and winter were recorded as 26% and 13% in Ashkezar and Abarkooh in Yazd province, respectively. Different nymph stages of the insect vector, Orosius albicinctus, were identified on tamarisk (Tamarix aphylla) and saxaul (Haloxylon persicum and H. aphyllum) in the winter. The highest population ofO. albicinctus, observed on tamarisk plants adjacent to the infected alfalfa fields in Milleshbar (Ardakan, Yazd province), suggested this as a possible source of natural spread of AWB

Calibration and equalisation of plastic scintillator detectors for antiproton annihilation identification over positron/positronium background

none53In this contribution, the system of the external plastic scintillator slabs of the AEgIS experiment is presented. These slabs, surrounding the superconducting magnet and operating at room temperature, are read out by photomultiplier tubes (PMTs) that are calibrated and equalised to be exploited as a whole detector with useful segmentation and redundancy to effectively detect single antiparticle annihilations. In particular, thanks to periodically recurring calibrations with cosmic rays and to a detailed study of the system in different operational conditions, including extensive Monte Carlo (MC) simulations, these scintillators can be used to identify antiproton annihilations over the constant background represented by cosmic rays and over the strongly time-dependent background due to positrons/positronium annihilations. By means of the sampling and digitization of the analog signal produced by each phototube and the consequent analysis of the amplitude of the recorded events, the energy released by the particle in the scintillator slab can be estimated consistently and with good accuracy. As a consequence, we are able to identify an amplitude range where positrons/positronium annihilations can be univocally excluded. This prerequisite allows us to exploit the array of external plastic scintillators for antihydrogen annihilations tagging.noneZurlo N.; Amsler C.; Antonello M.; Belov A.; Bonomi G.; Brusa R.S.; Caccia M.; Camper A.; Caravita R.; Castelli F.; Cerchiari G.; Comparat D.; Consolati G.; Demetrio A.; Di Noto L.; Doser M.; Fani M.; Ferragut R.; Gerber S.; Giammarchi M.; Gligorova A.; Gloggler L.; Guatieri F.; Haider S.; Hinterberger A.; Kellerbauer A.; Khalidova O.; Krasnicky D.; Lagomarsino V.; Malbrunot C.; Mariazzi S.; Matveev V.; Muller S.R.; Nebbia G.; Nedelec P.; Oberthaler M.; Oswald E.; Pagano D.; Penasa L.; Petracek V.; Prelz F.; Prevedelli M.; Rienaecker B.; Rohne O.M.; Rotondi A.; Sandaker H.; Santoro R.; Testera G.; Tietje I.C.; Toso V.; Wolz T.; Yzombard P.; Zimmer C.Zurlo, N.; Amsler, C.; Antonello, M.; Belov, A.; Bonomi, G.; Brusa, R. S.; Caccia, M.; Camper, A.; Caravita, R.; Castelli, F.; Cerchiari, G.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Doser, M.; Fani, M.; Ferragut, R.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Gloggler, L.; Guatieri, F.; Haider, S.; Hinterberger, A.; Kellerbauer, A.; Khalidova, O.; Krasnicky, D.; Lagomarsino, V.; Malbrunot, C.; Mariazzi, S.; Matveev, V.; Muller, S. R.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Oswald, E.; Pagano, D.; Penasa, L.; Petracek, V.; Prelz, F.; Prevedelli, M.; Rienaecker, B.; Rohne, O. M.; Rotondi, A.; Sandaker, H.; Santoro, R.; Testera, G.; Tietje, I. C.; Toso, V.; Wolz, T.; Yzombard, P.; Zimmer, C

Developments for pulsed antihydrogen production towards direct gravitational measurement on antimatter

A main scientific goal of the AEgIS \uaf experiment is the direct measurement of the Earth\u2019s local gravitational acceleration g on antihydrogen. The Weak Equivalence Principle is a foundation of General Relativity. It has been extensively tested with ordinary matter but very little is known about the gravitational interaction between matter and antimatter. Antihydrogen is produced in AEgIS \uaf via resonant charge-exchange reaction between cold Rydberg-excited positronium and cooled down antiprotons. The achievements for the development of a pulsed cold antihydrogen source are presented. Large number of antiprotons, necessary for a significant production rate of antihydrogen, are captured, accumulated, compressed and cooled over an extended period of time. Positronium (Ps) is formed through e+-Ps conversion in a silica porous target at 10 K temperature in a reflection geometry inside the main apparatus. The so-formed Ps cloud is then laser-excited to Rydberg levels, for the first time in a 1 T magnetic field. Consequently, a detailed characterization of the Ps source for antihydrogen production in magnetic field needed to be performed. Several detection techniques are extensively used to monitor antiproton and positron manipulations in the formation process of antihydrogen inside the main apparatus. Positronium detection techniques underwent extensive improvements in sensitivity during the last antiproton run. At the same time, major efforts to improve integrate and commission the detectors sensitive to antihydrogen production took place

Gravity and antimatter: the AEgIS experiment at CERN

International audienceFrom the experimental point of view, very little is known about the gravitational interaction between matter and antimatter. In particular, the Weak Equivalence Principle, which is of paramount importance for the General Relativity, has not yet been directly probed with antimatter. The main goal of the AEgIS experiment at CERN is to perform a direct measurement of the gravitational force on antimatter. The idea is to measure the vertical displacement of a beam of cold antihydrogen atoms, traveling in the gravitational field of the Earth, by the means of a moiré deflectometer. An overview of the physics goals of the experiment, of its apparatus and of the first results is presented

Gravity and antimatter: The AEgIS experiment at CERN

From the experimental point of view, very little is known about the gravitational interaction between matter and antimatter. In particular, the Weak Equivalence Principle, which is of paramount importance for the General Relativity, has not yet been directly probed with antimatter. The main goal of the AEgIS experiment at CERN is to perform a direct measurement of the gravitational force on antimatter. The idea is to measure the vertical displacement of a beam of cold antihydrogen atoms, traveling in the gravitational field of the Earth, by the means of a moir\ue9 deflectometer. An overview of the physics goals of the experiment, of its apparatus and of the first results is presented