Does Poetry Make Nothing Happen? Campo, Rafael
JAMA : the journal of the American Medical Association,
05/2023, Letnik:
329, Številka:
20
Journal Article
Recenzirano
Campo examines whether poem makes nothing happen. The poem Fireflies opens with a counterfactual--the poem the author intended to write but did not is the poem that follows, which ends up reflecting ...the anguish following the May 2022 school shooting in Uvalde TX, where 19 children and 2 teachers were killed. He comments that "Fireflies" implicates us in survival and witness. The "nothing" (like ephemeral fireflies) that poetry makes happen is indeed something: an indelible expression of shared grief, an acknowledgement of common humanity in the face of immutable mortality, a blinking of light in the darkness. Ultimately, the senselessness made tangible here is of value if physicians and the lay public can put despair and political rhetoric aside to reduce firearm deaths and advance the public's health.
Almost all colloidal quantum dots (QDs) exhibit undesired photoluminescence (PL) blinking, which poses a significant obstacle to their use in numerous luminescence applications. An in‐depth study of ...the blinking behavior, along with the associated mechanisms, can provide critical opportunities for fabricating high‐quality QDs for diverse applications. Here the blinking of a large series of colloidal QDs is investigated with different surface ligands, particle sizes, shell thicknesses, and compositions. It is found that the blinking behavior of single alloyed CdSe/ZnS QDs with a shell thickness of up to 2 nm undergoes an irreversible conversion from Auger‐blinking to band‐edge carrier blinking (BC‐blinking). Contrastingly, single perovskite QDs with particle sizes smaller than their Bohr diameters exhibit reversible conversion between BC‐blinking and more pronounced Auger‐blinking. Changes in the effective trapping sites under different excitation conditions are found to be responsible for the blinking type conversions. Additionally, changes in shell thickness and particle size of QDs have a significant effect on the blinking type conversions due to altered wavefunction overlap between excitons and effective trapping sites. This study elucidates the discrepancies in the blinking behavior of various QD samples observed in previous reports and provides deeper understanding of the mechanisms underlying diverse types of blinking.
The photoluminescence blinking type of some alloyed CdSe/ZnS quantum dots can be irreversibly converted from Auger‐blinking to BC‐blinking, while the photoluminescence blinking type of some perovskite quantum dots can be reversibly converted from BC‐blinking to a more pronounced Auger‐blinking.
Herein, we reported a simple, fast, and quantitative theoretical descriptor ΔGC‐O that allows accurate predictions of a wide range of spontaneously blinking rhodamines. ΔGC‐O denotes the Gibbs free ...energy differences between the closed and open forms of rhodamines and has a good linear relationship with experimental pKcycl values. This correlation affords an effective guide for the quantitative designs of spontaneously blinking rhodamines and eliminates trial‐and‐error. We have validated the predictive power of ΔGC‐O via the development of two spontaneously blinking rhodamines of different colors and enhanced brightness. We also demonstrated their super‐resolution imaging utilities in dynamic live‐cell imaging. We expect that ΔGC‐O will greatly facilitate the efficient creations of spontaneously blinking fluorophores and aid the advancements of super‐resolution bioimaging techniques.
A correlation has been discovered between calculated ΔGC‐O and experimental pKcycl values. Guided by this correlation, we quantitatively designed five spontaneously blinking rhodamines and validated two of them, and further demonstrate their live‐cell dynamic super‐resolution imaging utilities.
Single‐molecule localization microscopy (SMLM) has found extensive applications in various fields of biology and chemistry. As a vital component of SMLM, fluorophores play an essential role in ...obtaining super‐resolution fluorescence images. Recent research on spontaneously blinking fluorophores has greatly simplified the experimental setups and extended the imaging duration of SMLM. To support this crucial development, this review provides a comprehensive overview of the development of spontaneously blinking rhodamines from 2014 to 2023, as well as the key mechanistic aspects of intramolecular spirocyclization reactions. We hope that by offering insightful design guidelines, this review will contribute to accelerating the advancement of super‐resolution imaging technologies.
Spontaneously blinking fluorophores have the potential to significantly simplify experimental setups and extend the imaging duration of single‐molecule localization microscopy. This review offers an overview of the development of spontaneously blinking rhodamines from 2014 to 2023, as well as an in‐depth analysis of the mechanistic aspects of spontaneous blinking.
Blinking is vital to maintain the integrity of the ocular surface and its characteristics such as blink duration and speed can vary significantly, depending on the health of the eyes. The blink is so ...rapid that special techniques are required to characterize it. In this study, a high-speed camera was used to record and characterize voluntary blinking. The blinking motion of 25 healthy volunteers was recorded at 600 frames per second. Master curves for the palpebral aperture and blinking speed were constructed using palpebral aperture versus time data taken from the high-speed camera recordings, which show that one blink can be divided into four phases; closing, closed, early opening and late opening. Analysis of data from the high-speed camera images was used to calculate the palpebral aperture, peak blinking speed, average blinking speed and duration of voluntary blinking and compare it with data generated by other methods previously used to evaluate voluntary blinking. The advantages of the high-speed camera method over the others are discussed, thereby supporting the high potential usefulness of the method in clinical research.
Blinking kinematics characterization during digital displays use Talens-Estarelles, Cristian; Esteve-Taboada, José Juan; Sanchis-Jurado, Vicent ...
Graefe's archive for clinical and experimental ophthalmology,
04/2022, Letnik:
260, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Purpose
This study aimed to assess the differences in blinking kinematics while reading on different digital displays and a control condition.
Methods
Thirty-two young healthy individuals were ...included in this prospective clinical study. The blinks of subjects were recorded for 150 s while reading on a laptop computer, tablet, e-reader, and smartphone and a control condition. Blinks were recorded using an eye-tracking device and were analyzed by means of image analysis to obtain a non-invasive detailed description of the blink movement.
Results
Blink rate decreased when reading on all displays compared to the control (
p
< 0.0005), although no differences were obtained amongst displays (
p
> 0.05). The percentage of incomplete blinks was higher with the computer compared to the control (
p
= 0.043), and lower with the smartphone compared to the rest of the conditions (
p
≤ 0.015). Blink amplitude was smaller when reading from handheld devices compared to the control (
p
< 0.0005) and the computer (
p
≤ 0.048). Closing and opening blink durations remained unvaried amongst conditions (
p
> 0.05), while opening and closing speeds were greater for the control and the computer compared to the handheld displays (
p
< 0.0005). Finally, contact and total blink durations were shorter during computer reading compared to the control (
p
= 0.004 and
p
= 0.017, respectively).
Conclusion
Blinking kinematics vary considerably amongst displays and with respect to baseline, with these differences being probably attributed to differences in the way the displays are set up and the cognitive demand of the task.
Near‐infrared (NIR) fluorophores are highly desirable for super‐resolution fluorescence microscopy; however, their optical properties are typically relatively poor, with low photo‐intensity (mean ...photon number below 1000), and unfavorably high on‐off blinking duty cycle. In this work, the synthesis and characterization of tetrabenzodinaphthopyranthren (TBDNP) derivative as a novel nanographene that exhibits NIR emission in the range of 800–1000 nm with a photoluminescence quantum yield of 14% are reported. TBDNP demonstrated excellent self‐blinking properties, in particular, mean photon number of >3000 and a low on–off‐duty cycle (≈10−4), which are superior to reported NIR dyes, and can be successfully employed for the NIR super‐resolution imaging. Moreover, TBDNP serves also as a chiral fluorophore, showing notable chiroptical activities from 300 to 850 nm with a high dissymmetry factor (gabs) of 0.032 at 574 nm.
Tetrabenzodinaphthopyranthrene (TBDNP) with a combination of zigzag and fjord edges has been synthesized. TBDNP exhibits NIR emission in the range of 800–1000 nm with a photoluminescence quantum yield of 14%, and excellent self‐blinking properties compared to reported near‐infrared dyes. Moreover, TBDNP displays notable chiroptical properties with strong chiroptical activities from 300 to 850 nm and high gabs up to 0.032 at 574 nm.
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