Iron based nanoparticles have shown promise in biomedical applications by possessing diagnostic and therapeutic capabilities. Currently, superparamagnetic iron oxide nanoparticles (SPIONs) are the ...standard magnetic materials used for magnetic based imaging and hyperthermia therapeutics due to their good magnetic properties, biocompatibility, and stability. However, further improvement of iron-based nanoparticles for such applications can be achieved by creating nanoparticles that possess a pure iron core. Therefore, this study investigates a one-pot synthesis of superparamagnetic iron core–shell nanoparticles using a thermal decomposition of iron pentacarbonyl. Reaction time and surfactant quantities were modified to investigate possible size, shape, and dispersion variations. Characterizations included transmission electron microscopy, x-ray diffraction, Mössbauer spectroscopy, vibrating sample magnetometry, zeta potential, and cytotoxicity studies. From this method, core–shell, monodispersed nanoparticles averaging 14 nm in size were produced and displayed good colloidal stability and high magnetic saturation up to 130 emu/g. Iron nanoparticles were coated with 1,2- distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy- (polyethylene glycol)-2000 (ammonium salt) (DSPE-mPEG) polymer to increase biocompatibility and showed low cytotoxicity. The nanoparticles reported display high potential for magnetic imaging and magnetic hyperthermia applications.
Abstract
This article examines how the podcast Thirst Aid Kit makes Black women’s desires—often erased or distorted in media—audible. Using Critical Technocultural Discourse Analysis (CTDA) and ...feminist close reading, I make three interrelated arguments: (1) The hosts’ use of regional, Black vernaculars and cultural touchstones disrupts podcasting’s Whiteness and builds intimacy with Black women listeners; (2) The podcast’s aural expressions of thirst articulate Black women’s desires rather than shield them from broader publics; (3) The show’s expression of thirst is connected to the romance genre; however, Thirst Aid Kit, ruptures the genre’s investment in Whiteness and the happy ending. This article builds from and intervenes in podcasting research, studies of Black women and media, and popular romance studies.
Intranasal oxytocin therapy has been used to improve various aspects of autism spectrum disorder on the basis of tenuous results from small studies. In a randomized trial involving 290 participants 3 ...to 17 years of age with autism spectrum disorder, daily use of oxytocin did not improve measures of social interaction as compared with placebo over a period of 24 weeks.
Objective:Despite evidence for the validity of premenstrual dysphoric disorder (PMDD) and the inclusion of the disorder in DSM-5, variable diagnostic practices compromise the construct validity of ...the diagnosis and threaten the clarity of efforts to understand and treat its underlying pathophysiology. In an effort to hasten and streamline the translation of the DSM-5 criteria for PMDD into terms compatible with existing research practices, the authors present the development and initial validation of the Carolina Premenstrual Assessment Scoring System (C-PASS). The C-PASS (available as a worksheet, Excel macro, and SAS macro) is a standardized scoring system for making DSM-5 PMDD diagnoses using two or more months of daily symptom ratings with the Daily Record of Severity of Problems (DRSP).Method:Two hundred women recruited for retrospectively reported premenstrual emotional symptoms provided two to four months of daily symptom ratings on the DRSP. Diagnoses made by expert clinician and by the C-PASS were compared.Results:Agreement of C-PASS diagnosis with expert clinical diagnosis was excellent; overall correct classification by the C-PASS was estimated at 98%. Consistent with previous evidence, retrospective reports of premenstrual symptom increases were a poor predictor of prospective C-PASS diagnosis.Conclusions:The C-PASS is a reliable and valid companion protocol to the DRSP that standardizes and streamlines the complex, multilevel diagnosis of DSM-5 PMDD. Consistent use of this robust diagnostic method would result in more clearly defined, homogeneous samples of women with PMDD, thereby improving the clarity of studies seeking to characterize and treat the underlying pathophysiology of the disorder.
•Veterans with comorbid post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI) exhibited enhanced responses to background information or distractors.•A comorbid diagnosis of PTSD and ...TBI was associated with reduced ERPs to task-relevant targets in a simple executive attention task.•Neurophysiological indices of attention and inhibition were associated with diagnosis, but not with PTSD symptom severity.
Emotion regulation and cognitive executive control are significantly impaired in both post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI). These illnesses are increasingly common in veterans and their co-occurrence may exacerbate symptoms and recovery. The current study sought to investigate neural correlates of these impairments via event-related potentials (ERPs) and examined the association of PTSD symptom severity and impulsivity with these correlates.
Electroencephalographic data from seventy-nine veterans with PTSD and TBI and 17 control participants were recorded during a visual emotional oddball task and analyzed for the N2 and P3b ERPs.
Results revealed that veterans showed a reduced P3b ERP in response to both target images and standard images. However, for standard images that followed a negative emotional distractor, the veterans showed a heightened N2 amplitude while the controls did not. In addition, impulsivity predicted modulation of the P3b across stimulus conditions, with a greater P3b amplitude associated with an increase in impulsivity.
These findings suggest that veterans showed hyper-responsivity to background information and reduced ERPs to task-relevant information.
These findings may reflect heightened internal states that create neural noise and a reduced ability to modulate relevant responses.
The application of Mössbauer spectroscopy to luminescent materials is described. Many solids doped with europium are luminescent, i.e., when irradiated with light they emit light of a longer ...wavelength. These materials therefore have practical applications in tuning the light output of devices like light emitting diodes. The optical properties are very different for the two possible valence states Eu 2 + and Eu 3 + , the former producing ultraviolet/visible light that shifts from violet to red depending on the host and the latter red light, so it is important to have a knowledge of their behavior in a sample environment. Photoluminescence spectra cannot give a quantitative analysis of Eu 2 + and Eu 3 + ions. Mössbauer spectroscopy, however, is more powerful and gives a separate spectrum for each oxidation state enabling the relative amount present to be estimated. The oxidation state can be identified from its isomer shift which is between − 12 and − 15 mm/s for Eu 2 + compared to around 0 mm/s for Eu 3 + . Furthermore, within each oxidation state, there are changes depending on the ligands attached to the europium: the shift is more positive for increased covalency of the bonding ligand X, or Eu concentration, and decreases for increasing Eu-X bond length.
Magnetic nanoparticles (MNPs) have a wide range of applications; an area of particular interest is magnetic particle imaging (MPI). MPI is an imaging modality that utilizes superparamagnetic iron ...oxide particles (SPIONs) as tracer particles to produce highly sensitive and specific images in a broad range of applications, including cardiovascular, neuroimaging, tumor imaging, magnetic hyperthermia and cellular tracking. While there are hurdles to overcome, including accessibility of products, and an understanding of safety and toxicity profiles, MPI has the potential to revolutionize research and clinical biomedical imaging. This review will explore a brief history of MPI, MNP synthesis methods, current and future applications, and safety concerns associated with this newly emerging imaging modality.
Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and ...treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose. To extend the practical use of ionizing radiation-based medical techniques, such as magnetic resonance imaging (MRI)-guided RT, a more precise measurement of the internal radiation dose internally is required. In this work, a novel approach is presented to measure dose in liquids for potential future in vivo applications. The strategy relies on MRI contrast agents (CAs) that provide a dose-sensitive signal. The demonstrated materials are (citrate-capped) CaF2 nanoparticles (NPs) doped with Eu3+ or Fe2+/Fe3+ ions. Free electrons generated by ionizing radiation allow the reduction of Eu3+, which produces a very small contrast in MRI, to Eu2+, which induces a strong contrast. Oxidative species generated by high-energy X-rays can be measured indirectly using Fe2+ because it oxidizes to Fe3+, increasing the contrast in MRI. Notably, in the results, a strong increase in the proton relaxation rates is observed for the Eu3+-doped NPs at 40 kV. At 6 MV, a significant increase in proton relaxation rates is observed using CaF2 NPs doped with Fe2+/Fe3+ after irradiation. The presented concept shows great promise for use in the clinic to measure in vivo local ionizing radiation dose, as these CAs can be intravenously injected in a saline solution.
Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and ...treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose. To extend the practical use of ionizing radiation-based medical techniques, such as magnetic resonance imaging (MRI)-guided RT, a more precise measurement of the internal radiation dose internally is required. In this work, a novel approach is presented to measure dose in liquids for potential future
applications. The strategy relies on MRI contrast agents (CAs) that provide a dose-sensitive signal. The demonstrated materials are (citrate-capped) CaF
nanoparticles (NPs) doped with Eu
or Fe
/Fe
ions. Free electrons generated by ionizing radiation allow the reduction of Eu
, which produces a very small contrast in MRI, to Eu
, which induces a strong contrast. Oxidative species generated by high-energy X-rays can be measured indirectly using Fe
because it oxidizes to Fe
, increasing the contrast in MRI. Notably, in the results, a strong increase in the proton relaxation rates is observed for the Eu
-doped NPs at 40 kV. At 6 MV, a significant increase in proton relaxation rates is observed using CaF
NPs doped with Fe
/Fe
after irradiation. The presented concept shows great promise for use in the clinic to measure
local ionizing radiation dose, as these CAs can be intravenously injected in a saline solution.
Abstract Social cognition is impaired in people with schizophrenia and these deficits are strongly correlated with social functioning. Oxytocin is a hypothalamic peptide that contributes to maternal ...infant bonding and has diverse pro-social effects in adults. This study tested the hypothesis that 12 weeks of intranasal oxytocin will improve social cognitive function in outpatients with schizophrenia and schizoaffective disorder. Sixty-eight eligible participants were randomized to oxytocin (24 IU twice daily) or placebo. Social cognitive function was assessed using the Emotion Recognition-40, Brüne Theory of Mind, Reading the Mind in the Eyes test, Trustworthiness task and Ambiguous Intentions Hostility Questionnaire at baseline, 6 weeks and 12 weeks. In addition, social function was assessed using the Specific Levels of Functioning Scale and a role-play test, and psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). Fifty-five participants completed the 12-week trial. The study found no evidence for a differential advantage of oxytocin over placebo on social cognition. Among secondary outcomes, there was a modest advantage for oxytocin over placebo on a component of social functioning, although there was also evidence that the placebo group outperformed the oxytocin group on the role-play task. No between-group differences emerged on measures of psychopathology in pre-specified comparisons, but oxytocin showed significant within-group reduction in PANSS negative symptoms and significant between-group improvement in negative symptoms in the schizophrenia subgroup. Further testing is needed to clarify whether oxytocin has therapeutic potential for social cognitive deficits and/or negative symptoms in people with schizophrenia.
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