Analytical description of high-aperture STED resolution with 0-2π\pi vortex phase modulation

Stimulated emission depletion (STED) can achieve optical super-resolution, with the optical diffraction limit broken by the suppression on the periphery of the fluorescent focal spot. Previously, it is generally experimentally accepted that there exists an inverse square root relationship with the STED power and the resolution, yet without strict analytical description. In this paper, we have analytically verified the relationship between the STED power and the achievable resolution from vector optical theory for the widely used 0-2$\pi$ vortex phase modulation. Electromagnetic fields of the focal region of a high numerical aperture objective are calculated and approximated into polynomials, and analytical expression of resolution as a function of the STED intensity has been derived. As a result, the resolution can be estimated directly from the measurement of the saturation power of the dye and the STED power applied.Comment: (19 pages

X-Ray Spectral and Timing Observations of Cygnus X-2

We report on a joint BeppoSAX/RXTE observation of the Z-type low-mass X-ray binary Cyg X-2. The source was in the so-called high overall intensity state and in less than 24 hr went through all three branches of the Z track. The continuum X-ray spectrum could be described by the absorbed sum of a soft thermal component, modeled as either a blackbody or a multicolor disk blackbody, and a Comptonized component. The timing power spectrum showed several components, including quasi-periodic oscillations in the range 28-50 Hz while the source was on the horizontal branch (horizontal branch oscillation; HBO). We found that the HBO frequency was well correlated with the parameters of the soft thermal component in the X-ray spectrum. We discuss implications of this correlation for models of the HBO

Discovery of Microsecond Soft Lags in the X-Ray Emission of the Atoll Source 4U1636-536

Exploiting the presence of kilohertz quasi-periodic oscillations (QPOs) in the timing power spectrum, we find that the soft x-ray emission of the neutron-star X-ray binary and atoll source 4U1636-536 modulated at the QPO frequency lags behind that of the hard x-ray emission. Emission in the 3.8-6.4 keV band is delayed by 25.0 +/- 3.3 microseconds relative to the 9.3-69 keV band. The delay increases in magnitude with increasing energy. Our results are consistent with those of Vaughan et al. (1997), when the sign is corrected (Vaughan et al. 1998), for the atoll source 4U1608-52. The soft lag could be produced by Comptonization of hard photons injected into a cooler electron cloud or by intrinsic spectral softening of the emission during each oscillation cycle.Comment: Accepted to the Astrophysical Journal Letters, 4 page

Characterizing mRNA Interactions with RNA Granules during Translation Initiation Inhibition

When cells experience environmental stresses, global translational arrest is often accompanied by the formation of stress granules (SG) and an increase in the number of p-bodies (PBs), which are thought to play a crucial role in the regulation of eukaryotic gene expression through the control of mRNA translation and degradation. SGs and PBs have been extensively studied from the perspective of their protein content and dynamics but, to date, there have not been systematic studies on how they interact with native mRNA granules. Here, we demonstrate the use of live-cell hybridization assays with multiply-labeled tetravalent RNA imaging probes (MTRIPs) combined with immunofluorescence, as a tool to characterize the polyA+ and β-actin mRNA distributions within the cytoplasm of epithelial cell lines, and the changes in their colocalization with native RNA granules including SGs, PBs and the RNA exosome during the inhibition of translational initiation. Translation initiation inhibition was achieved via the induction of oxidative stress using sodium arsenite, as well as through the use of Pateamine A, puromycin and cycloheximide. This methodology represents a valuable tool for future studies of mRNA trafficking and regulation within living cells

Examining emotion regulation in binge-eating disorder

Background Inefficient mechanisms of emotional regulation appear essential in understanding the development and maintenance of binge-eating disorder (BED). Previous research focused mainly on a very limited emotion regulation strategies in BED, such as rumination, suppression, and positive reappraisal. Therefore, the aim of the study was to assess a wider range of emotional regulation strategies (i.e. acceptance, refocusing on planning, positive refocusing, positive reappraisal, putting into perspective, self-blame, other-blame, rumination, and catastrophizing), as well as associations between those strategies and binge-eating-related beliefs (negative, positive, and permissive), and clinical variables (eating disorders symptoms, both anxiety, depressive symptoms, and alexithymia). Methods Women diagnosed with BED (n = 35) according to the DSM-5 criteria and healthy women (n = 41) aged 22–60 years were assessed using: the Eating Attitudes Test-26, the Eating Beliefs Questionnaire-18, the Hospital Anxiety and Depression Scale, the Toronto Alexithymia Scale-20, the Cognitive Emotion Regulation Questionnaire, and the Difficulties in Emotion Regulation Scale. Statistical analyses included: Student t - tests or Mann–Whitney U tests for testing group differences between BED and HC group, and Pearson’s r coefficient or Spearman’s rho for exploring associations between the emotion regulation difficulties and strategies, and clinical variables and binge-eating-related beliefs in both groups. Results The BED group presented with a significantly higher level of emotion regulation difficulties such as: nonacceptance of emotional responses, lack of emotional clarity, difficulties engaging in goal-directed behavior, impulse control difficulties, and limited access to emotion regulation strategies compared to the healthy controls. Moreover, patients with BED were significantly more likely to use maladaptive strategies (rumination and self-blame) and less likely to use adaptive strategies (positive refocusing and putting into perspective). In the clinical group, various difficulties in emotion regulation difficulties occurred to be positively correlated with the level of alexithymia, and anxiety and depressive symptoms. Regarding emotion regulation strategies, self-blame and catastrophizing were positively related to anxiety symptoms, but solely catastrophizing was related to the severity of eating disorder psychopathology. Conclusions Our results indicate an essential and still insufficiently understood role of emotional dysregulation in BED. An especially important construct in this context seems to be alexithymia, which was strongly related to the majority of emotion regulation difficulties. Therefore, it might be beneficial to pay special attention to this construct when planning therapeutic interventions, as well as to the maladaptive emotion regulation strategies self-blame and catastrophizing, which were significantly related to BED psychopathology

Valence and Motivation as Predictors of Student Time Use in Everyday Life: An Experience Sampling Study

Koudela-Hamila S, Grund A, Santangelo P, Ebner-Priemer UW. Valence and Motivation as Predictors of Student Time Use in Everyday Life: An Experience Sampling Study. FRONTIERS IN PSYCHOLOGY. 2019;10: 1430.Popular descriptions of studying frequency show remarkable discrepancies: students complain about their workload, and alumni describe freedom and pleasure. Unfortunately, empirical evidence on student time use is sparse. To investigate time use and reveal contributing psychological factors, we conducted an e-diary study. One hundred fifty-four students reported their time use and valence hourly over 7 days, both at the start of the semester and during their examination period. Motivational problems, social support and self-control were assessed once via questionnaires. Whereas the mean academic time use was in the expected range, the between-subject differences were substantial. We used multilevel modeling to separately analyze the within- and between-subject associations of valence as within factor and time use and social support, self-control, and motivation as between factors and time use. The analyses revealed the importance of affective factors on a within-subject level. Before studying, valence was already low, and it deteriorated further during studying. As expected at the between-subject level, motivational problems were related to less time studying, whereas surprisingly, self-control had no effect. The findings at the start of the semester were replicated in the examination period

Target accessibility and signal specificity in live-cell detection of BMP-4 mRNA using molecular beacons

The ability to visualize mRNA in single living cells and monitor in real-time the changes of mRNA level and localization can provide unprecedented opportunities for biological and disease studies. However, the mRNA detection specificity and sensitivity are critically dependent on the selection of target sequences and their accessibility. We carried out an extensive study of the target accessibility of BMP-4 mRNA using 10 different designs of molecular beacons (MBs), and identified the optimal beacon design. Specifically, for MB design 1 and 8 (MB1 and MB8), the fluorescent intensities from BMP-4 mRNA correlated well with the GFP signal after upregulating BMP-4 and co-expressing GFP using adenovirus, and the knockdown of BMP-4 mRNA using siRNA significantly reduced the beacon signals, demonstrating detection specificity. The beacon specificity was further confirmed using blocking RNA and in situ hybridization. We found that fluorescence signal from MBs depends critically on target sequences; the target sequences corresponding to siRNA sites may not be good sites for beacon-based mRNA detection, and vice versa. Possible beacon design rules are identified and approaches for enhancing target accessibility are discussed. This has significant implications to MB design for live cell mRNA detection

Investigating binge eating using ecological momentary assessment: The importance of an appropriate sampling frequency

With great interest, we read the recently published review on emotion regulation in binge eating disorder (BED) by Dingemans et al. [1].[...

Specificity of emotion sequences in borderline personality disorder compared to posttraumatic stress disorder, bulimia nervosa, and healthy controls: an e-diary study

Background: Patients with borderline personality disorder (BPD) exhibit dysregulated emotion sequences in daily life compared to healthy controls (HC). Empirical evidence regarding the specificity of these findings is currently lacking. Methods: To replicate dysregulated emotion sequences in patients with BPD and to investigate the specificity of the sequences, we used e-diaries of 43 female patients with BPD, 28 patients with posttraumatic stress disorder (PTSD), 20 patients with bulimia nervosa (BN), and 28 HC. To capture the rapid dynamics of emotions, we prompted participants every 15 min over a 24-h period to assess their current perceived emotions. We analyzed group differences in terms of activation, persistence, switches, and down-regulation of emotion sequences. Results: By comparing patients with BPD to HC, we replicated five of the seven previously reported dysregulated emotion sequences, as well as 111 out of 113 unaltered sequences. However, none of the previously reported dysregulated emotion sequences exhibited specificity, i.e., none revealed higher frequencies compared to the PTSD group or the BN group. Beyond these findings, we revealed a specific finding for patients with BN, as they most frequently switched from anger to disgust. Conclusions: Replicating previously found dysregulated and unaltered emotional sequences strengthens the significance of emotion sequences. However, the lack of specificity points to emotion sequences as transdiagnostic features