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Reading Speed and Visual Acuity in Photopic and Mesopic Conditions After Bilateral Implantation of Diffractive Multifocal Intraocular Lenses
No full textPurpose
To assess functional visual performance – particularly reading speed - under photopic and mesopic conditions in patients bilaterally implanted with either the AT LISA Tri 839MP or Tecnis Synergy DFR00V diffractive multifocal intraocular lenses (IOL).
Design
Prospective randomized controlled trial.
Methods
This trial included 60 patients that underwent bilateral cataract surgery with implantation of either the AT LISA Tri or Synergy IOLs. At 3 months postoperatively, distance-corrected visual acuity (VA) and distance-corrected reading speed were measured under photopic (85 cd/m²) and mesopic (3 cd/m²) conditions. Photopic defocus curves were also analyzed and compared.
Results
Mesopic VA was significantly worse than photopic VA by ∼1 ETDRS line, without inter-IOL differences. Photopic reading speeds were 143.4 ± 40.0 and 136.4 ± 27.0 wpm for the AT LISA Tri and Synergy, respectively. Mesopic reading speeds declining significantly to 38.2 ± 34.2 and 22.4 ± 29.7 wpm under mesopic conditions, respectively. Mesopic reading speed was significantly lower than in photopic conditions for both groups.
Conclusions
Standard VA testing may underestimate functional limitations of multifocal IOLs under mesopic conditions. The substantial loss of reading speed suggests that mesopic near vision is impaired. Low luminance reading speed is a practical, patient-relevant endpoint and should be considered in IOL evaluations
Towards the understanding of Keim'sche Mineralfarben in architectural paints: Material characterization and phase quantification on selected historical pigment admixtures
Full text link‘Keim'sche Mineralfarben’ are widely recognized silicate-based paints historically employed for painting and decorating architectural surfaces, as well as in the conservation and restoration of historic buildings and monuments, particularly where high-quality architectural finishes are required. Comprehensive knowledge of the composition of historical Keim'sche Mineralfarben pigment admixtures and their evolution—particularly for dating purposes—remains limited within the field of architectural conservation. The study demonstrates the effectiveness of a multi-analytical approach in characterizing the composition and phase quantification of selected yellow-to brownish-toned historical Keimfarben pigment admixtures and suggests a methodology for the characterization of this product on site, offering new perspectives on understanding the chronology of the paint layers, thus planning future restoration interventions. A multi-analytical approach was employed, combining optical microscopy, X-ray fluorescence, in situ Raman and micro-Raman spectroscopy, ATR-FTIR, and X-ray powder diffraction with Rietveld refinement. The results show that the studied Keimfarben pigment admixtures are composed of calcite, fluorite, kaolinite, quartz, barite, rutile, and witherite, as well as different quantities of hematite, goethite, and eskolaite depending on the hue. Certain identified phases have been shown to serve as diagnostic markers, limiting the application of the examined products on architectural surfaces to the period between the 1958 and 1980s. Moreover, quantitative analysis of the components may help elucidate their function within the admixture and will be essential for advancing the investigation into their relevance in the coating's formation
Exact simulation of stochastic volatility models based on conditional Fourier-cosine method
No full textThe traditional methodology used for the exact simulation of stochastic volatility models based on the Gil–Pelaez formula presents implementation problems that are observed by many researchers and practitioners. In particular, although conventionally considered exact, such a method presents a difficult control of the error. The bias of the Monte Carlo simulation estimator can only be computed numerically and is controlled by two parameters, typically determined by running time-consuming simulations under different tuning parameter configurations until an optimal setup is found. In this paper, we propose a new exact simulation scheme based on the Fourier-cosine method, which approximates a probability density given the characteristic function as follows: the density is truncated on a finite interval, and approximated by a classical Fourier-cosine series. The method allows full error control via an effective automatic identification of the tuning parameters given a user-supplied error tolerance. The new approach offers the following advantages: improved control of the error, simplified implementation, and reduction in computing time. The error is controlled by only one parameter instead of two. This parameter has a clear interpretation: it is the maximum tolerable bias. This facilitates the implementation, since the maximum bias becomes an input of the simulation algorithm, instead of an output, and can be set a priori, before running simulations. Our analysis shows that the proposed exact simulation scheme is computationally faster than the traditional one, and presents an improved speed-accuracy profile with respect to alternative state-of-the-art fast approximated sampling schemes
Predicting pacemaker dependency after transcatheter aortic valve replacement: Analysis of ECG, clinical, and CT-imaging parameters
Full text linkObjectives
Conduction disturbances necessitating permanent pacemaker (PPM) implantation following transcatheter aortic valve replacement (TAVR) have been observed. However, limited data exist on ECG, clinical, and CT-imaging factors predicting PPM dependency after TAVR. This study aimed to identify predictors of pacemaker dependency in selected patients who required PPM implantation after TAVR with SAPIEN 3 prostheses.
Materials and Methods
This study included consecutive patients who underwent transfemoral TAVR with SAPIEN 3 prostheses at our institution between May 2012 and December 2019. Exclusion criteria were incomplete or non-diagnostic data, valve-in-valve procedures, TAVR in mitral position, previous surgical repair, and pre-implanted PPM. The primary endpoint was PPM dependency, defined as ventricular pacing percentage ≥ 1 % at the first outpatient follow-up after PPM implantation post-TAVR. Regression analysis was performed to compare a limited prediction model for PPM dependency using only selected variables to a full model with all available variables.
Results
Out of 2105 patients who received TAVR, 350 (16.6 %) required pacemaker implantation post-TAVR. After exclusions, 301 patients remained, with 168 (55.8 %) PPM-dependent and 133 (44.2 %) non-dependent patients. Multivariate analysis identified prosthesis oversizing (OR: 1.09, p < 0.001), calcification below the left coronary cusp (LCC) (OR: 1.02, p < 0.001), and right bundle branch block (RBBB) prior to TAVR (OR: 2.20, p = 0.025) as significant predictors. A limited regression model predicted PPM dependency with an AUC of 0.752, significantly outperforming the full model (AUC: 0.660, p = 0.037).
Conclusion
RBBB prior to TAVR was the strongest predictor of PPM dependency post-TAVR, followed by prosthesis oversizing and calcification below the LCC. A limited prediction model with these variables demonstrated moderate predictive accuracy
Detection of subarachnoid hemorrhage by bilateral transcranial laser doppler fluxmetry allows long-term studies in mice
Full text linkBackground
The murine middle cerebral artery (MCA) perforation model is widely used to study subarachnoid hemorrhage (SAH) but typically requires invasive intracranial pressure (ICP) monitoring to prove successful induction of hemorrhage. However, ICP probe placement causes substantial additional parenchymal damage, confounding long-term structural and functional assessments. Therefore, we investigated whether bilateral transcranial cerebral blood flow (CBF) monitoring, which does not cause any parenchymal damage, can reliably detect SAH induction in mice.
New method
SAH was induced in 25 male C57BL/6 mice with simultaneous ICP and bilateral CBF monitoring over the MCA territory. An additional 40 mice underwent SAH surgery using only bilateral CBF monitoring (without ICP monitoring). Ipsilateral and contralateral CBF and ICP curves were analyzed to identify reliable predictors of successful SAH induction.
Results
MR imaging revealed progressive parenchymal injury caused by the ICP probe. SAH was reproducibly induced without ICP monitoring when bilateral CBF dropped > 50 % from baseline within 90 s after perforation. Using this minimally invasive approach, SAH could be consistently induced by different surgeons, with severity and outcomes comparable to those with ICP monitoring.
Comparison with existing methods and conclusion
ICP probe placement introduces parenchymal damage and may therefore limit the validity of long-term outcome studies. Our findings suggest that bilateral CBF monitoring can effectively replace ICP measurement, reducing invasiveness and enabling valid long-term SAH experiments in mice
Complementing business training with access to finance: Evidence from SMEs in Kenya
No full textThis paper investigates the complementarity between business training and timely access to financial capital for small and medium enterprises (SMEs) in Kenya. All participants in the business support program we study are offered training. One-third of participants are offered loans immediately after training (Concurrent Loan group), one-third are offered loans six weeks after training (Delayed Loan group), and the remaining third are offered loans after another four weeks (Control group). While a long time lag may reduce knowledge retention and application among SMEs, concurrent access to loans and associated business spending may divert the entrepreneurs’ attention away from improving business practices. We find evidence for the latter in both intention-to-treat and treatment-on-the-treated estimates. While SMEs in both Control and Delayed Loan groups improve their business practices, SMEs in the Concurrent Loan group who take loans do not improve their practices at all. Moreover, entrepreneurs who take loans spend less time on their businesses and experience declines in their business revenue
If she watches, I will share: The impact of private and public self-focus on children’s sharing behavior and the moral self-concept
No full textStates with a focus on oneself, such as observing oneself (private self-focus) and being observed by others (public self-focus), are proposed to increase the saliency of own motives and evaluations by others and thereby to influence behavior. These processes become particularly relevant toward the end of early childhood, around the same age when children’s moral self-concept (their view of themselves as prosocial agents) consolidates. This study advances the understanding of the role of self-focus on children’s prosocial behavior by considering their moral self-concept. We investigated how private self-focus and two facets of public self-focus affect sharing behavior, the moral self-concept, and their interrelation. In a preregistered study, we assessed 5- to 8-year-olds’ (N = 161, 84 female) sharing behavior and moral self-concept across four conditions. Children shared while observing themselves (private self-focus), while being observed by another child (reputation), while being observed by another child who could reciprocate later (reciprocity), or while not being observed (control). Generally, children shared more when observed by another person compared to when they were not in the focus of anybody, whereas observing themselves did not increase sharing. Children’s moral self-concept was positively correlated with sharing, particularly when being in public self-focus, while mean values did not differ between conditions. The study provides novel evidence for the specific role of the awareness of others’ evaluation in children’s prosocial behavior. It suggests a social grounding of the moral self-concept by revealing its particular role for sharing behavior when being in the focus of social attention
Association of breastfeeding duration with longitudinal changes in vertebral bone marrow, paraspinal muscle composition, and metabolic parameters in premenopausal women over five years
Full text linkObjective
To investigate the association between breastfeeding duration and longitudinal changes in MRI-based proton-density fat fraction (PDFF) of vertebral bone marrow, paraspinal musculature (PSM), and metabolic parameters in premenopausal women.
Methods
Thirty-seven women (age 36.3 ± 3.8 years) were evaluated with the subgroups of women who breastfed ≤8 months vs. >8 months. All women underwent a 3 T MRI scan, including chemical shift encoding-based water-fat separation, postpartum (11.10 ± 2.38 months) and at 5-year follow-up. Glucose metabolism was analyzed at both visits using the updated Homeostasis Model Assessment (HOMA-2). PDFF values of lumbar and thoracic vertebrae and PSM were assessed, along with the cross-sectional area of PSM. Associations between breastfeeding duration and changes in bone marrow and muscle composition were assessed using multivariable linear regression models adjusted for age and body mass index (BMI).
Results
Women who breastfed >8 months showed a greater decrease in PDFF of the lumbar vertebrae (−9.62 ± 5.42 % vs. −4.69 ± 7.72 %; p = 0.03) and autochthonous muscles (AM) (−1.32 ± 2.52 % vs. 0.37 ± 2.48 %; p = 0.047) between baseline and 5-year follow-up compared to women who breastfed ≤8 months. Breastfeeding >8 months was significantly associated with greater reductions in both PDFFlumbar (β = − 5.34 %; p = 0.03) and PDFFAM (β = − 1.84 %; p = 0.03) independent of baseline BMI and age.
Conclusion
Longer breastfeeding duration is associated with a higher decrease of vertebral bone marrow adiposity and fat infiltration of autochthonous muscles over 5 years in premenopausal women, indicating potential benefits for maternal bone and muscle composition
Clarifying the role of somatic and depressive symptoms in suicide risk: Evidence from a cross-sectional analysis
Full text linkBackground
Somatic symptoms are common in psychiatric and primary care populations, and their relationship with depression and suicidal ideation is complex. This study investigates the association between somatic symptoms and suicidal ideation, accounting for comorbid depressive symptoms.
Methods
This cross-sectional study included 521 in- and outpatient with PHQ-9 ≥ 6 or a positive response to item 9, indicative of suicidal thoughts. Somatic and depressive symptoms were assessed using the PHQ-15 and PHQ-2 or PHQ-9, respectively. Suicidal ideation was measured using the risk subscale of the SuPr-10; the protective subscale was included as a covariate. Associations were examined using correlation matrices and regression models.
Results
The sample was 68 % female with a mean age of 41 years; 52 % screened positive for suicidal ideation. PHQ-9 (mean = 14.8, SD = 5.0) and PHQ-15 scores (mean = 12.4, SD = 5.0) were moderately elevated. In a two-part regression model, higher depressive symptoms were associated with a reduced likelihood of reporting no suicidal ideation (OR = 0.50, 95 % CI: 0.41–0.62) and increased severity of suicidal ideation (IRR = 1.17, 95 % CI: 1.09–1.27). Somatic symptoms showed no meaningful direct effects but were indirectly associated with suicidal ideation via depressive symptoms (indirect effect OR = 1.05, 95 % CI: 1.03–1.07).
Conclusions
In individuals with somatic complaints, co-occurring depressive symptoms are strongly associated with suicidal ideation. Systematic depression screening is essential in somatically presenting patients