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The effect of duration of optotype presentation on visual acuity measures has been extensively studied under photopic conditions. However, systematic data on duration dependence of acuity values under mesopic and scotopic conditions is scarce, despite being highly relevant for many visual tasks including night driving, and for clinical diagnostic applications. The present study aims to address this void. We measured Landolt C acuity under photopic (90cd/m ), mesopic (0.7cd/m ), and scotopic (0.009cd/m ) conditions for several optotype presentation durations ranging from 0.1 to 10s using the Freiburg Acuity and Contrast Test. Two age groups were tested (young, 18-29years, and older, 61-74years). As expected, under all luminance conditions, better acuity values were found for longer presentation durations. Photopic acuity in young participants decreased by about 0.25 log units from 0.1 to 10s; mesopic vision mimicked the photopic visual behavior. Scotopic acuities depended more strongly on presentationopic vision, with considerable interindividual variability. The latter may reflect differences in aging and sub-clinical pathophysiological processes and might have consequences for visual performance during nocturnal activities such as driving at night. Acuity testing with briefly presented scotopic stimuli might increase the usefulness of acuity assessment for tracking of the health state of the visual system. Hormone receptor (HR) positive breast cancer has a high propensity for late recurrences that might be prevented with longer durations of endocrine therapy (ET). However, trials evaluating extended adjuvant ET have produced somewhat conflicting results. Additionally, ET is associated with not only day to day side effects that can impact quality of life, but more detrimental effects that can cause significant morbidity. Although patients with higher stage disease are at greater risk of late recurrences, even patients with stage 1 disease have a significant risk of recurrence after 5years. Current guidelines recommend extending therapy for patients with node-positive disease, but recommendations for patients with node-negative disease are less clear. This has led to the development of various genomic tests to aid oncologists in further individualizing their approach when it comes to deciding which subpopulation of patients with HR-positive breast cancer may benefit from extending their endocrine therapy beyondtely, genomic testing should help facilitate shared decision making between the patient and oncologist.The dental pulp, a non-mineralized connective tissue uniquely encased within the cavity of the tooth, provides a niche for diverse arrays of dental mesenchymal stem cells. Stem cells in the dental pulp, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHEDs) and stem cells from apical papilla (SCAPs), have been isolated from human tissues with an emphasis on their potential application to regenerative therapies. Recent studies utilizing mouse genetic models shed light on the identities of these mesenchymal progenitor cells derived from neural crest cells (NCCs) in their native conditions, particularly regarding how they contribute to homeostasis and repair of the dental tissue. The current concept is that at least two distinct niches for stem cells exist in the dental pulp, e.g., the perivascular niche and the perineural niche. The precise identities of these stem cells and their niches are now beginning to be unraveled thanks to sophisticated mouse genetic models, which lead to better understanding of the fundamental properties of stem cells in the dental pulp and the apical papilla in humans. The new knowledge will be highly instrumental for developing more effective stem cell-based regenerative therapies to repair teeth in the future.Mesenchymal stem cells (MSCs) hold enormous potential for the treatment of immune-related conditions and degenerative diseases, owing to their self-renewal and multilineage differentiation capabilities. Nevertheless, cellular senescence significantly impacts the quantity and quality of MSCs, limiting their clinical use. Mitochondria play essential roles in energy production by oxidative phosphorylation and metabolism of energy sources via the tricarboxylic acid cycle. Therefore, mitochondrial dysfunction is a primary cause of senescence in MSCs. Herein, we summarize the current knowledge regarding the mechanisms underlying mitochondrial dysfunction-associated cellular senescence. We also discuss potential methods to prevent or even reverse MSC senescence.A turn-on method for determining α-glucosidase activity is described using a chemical redox strategy in which the fluorescence of red fluorescent carbon dots (CDs) is modulated. FL118 The red fluorescent CDs were prepared using a solvothermal method with p-phenylenediamine and sodium citrate. The excitation and emission maxima of the CDs were 490 and 618 nm, respectively. Ce4+ ions catalyze the oxidation of the colorless substrate 3,3',5,5'-tetramethylbenzidine (TMB) to give a blue oxidized TMB product (oxTMB). Absorption by oxTMB overlaps with the red light emitted by the CDs because of the fluorescence inner filter effect; therefore the presence of oxTMB decreases the intensity of fluorescence emission by the CDs. However, hydrolysis of L-ascorbic acid-2-O-α-D-glucopyranosyl by the enzyme α-glucosidase causes formation of ascorbic acid . Ascorbic acid reduces oxTMB to TMB, so that the inner filter effect disappeared and the fluorescence recovered. The strategy allows α-glucosidase activity to be successfully determined down to 0.02 U mL-1 and gives a dynamic linear range of 0-5.5 U mL-1. The strategy is very selective for α-glucosidase activity in the presence of potentially interfering substances. The method has been successfully applied to the determination of α-glucosidase activity in spiked human serum samples and gave satisfactory results. Graphical Abstract Schematic of the method used to prepare the carbon dots and the mechanisms involved in determining α-glucosidase activity.As one critical parameter for organ perfusion, microcirculation and its monitoring are gaining increasing attention for modern intensive care medicine. The growing understanding of its importance in organ failure and the improved modes of its visualization mark microcirculation as an interesting target. Surrogate parameters for organ perfusion, like re-capillarization ("Recap") time, the "mottling score" or the measurement of serum lactate have long been established in clinical practice. A growing body of evidence is hinting towards online visualization of sublingual microcirculation using intravital video microscopy, which was shown to be of prognostic value. Furthermore, the measurement of objective and reproducible parameters hint towards use in individualized hemodynamic therapy.