Regular Light Research Articles

Comparison of Immunochromatographic Strips Using Colloidal Gold, Quantum Dots, and Upconversion Nanoparticles for Visual Detection of Norfloxacin in Milk Samples

Colloidal gold, quantum dots (QDs), and upconversion nanoparticles (UCNPs), which were respectively labeled with monoclonal antibody against norfloxacin (NOR), were employed as signal probes to establish three types of immunochromatographic strips, and the strips were evaluated according to their ability to detect NOR in milk samples. The results showed that the visual detection limit of NOR was 2.0 μg L−1 in the standard solution and 20.0 μg L−1 in milk samples when using colloidal gold-immunochromatographic strips (ICS). When QD-based fluorescence immunochromatographic strips (FICS) were used, the visual detection limit was 2.0 μg L−1 in the standard solution and 10.0 μg L−1 in milk samples. If UCNP-based FICS strips were employed, the visual limit of detection was 0.5 μg L−1 in the standard solution and 2.5 μg L−1 in milk samples. Besides, the results from the proposed methods showed high agreement with results yielded by using commercial ELISA kits, indicating the good accuracy of these strips. Compared with colloidal gold-ICS, QDs-FICS showed similar sensitivity in the standard solution and a two-fold higher sensitivity in milk samples. Meanwhile, UCNPs-FICS yielded the highest sensitivity both in standard solution and in milk samples, and they were also more stable in normal laboratory conditions (that is, they could be exposed to regular room light). Additionally, the two fluorescence nanoparticle-based test strips could be built with less antibody and coating antigens and can be cost-effective. In conclusion, the proposed QDs-FICS and UCNPs-FICS could be employed as cost-effective alternative methods for sensitive, rapid, and on-site detection of NOR in milk samples.

СОВЕРШЕНСТВОВАНИЕ МЕТОДИКИ ВЫПОЛНЕНИЯ ВЫСОКОТОЧНОГО НИВЕЛИРОВАНИЯ ЦИФРОВЫМИ НИВЕЛИРАМИ В УСЛОВИЯХ НЕДОСТАТОЧНОЙ ОСВЕЩЕННОСТИ ШТРИХКОДОВЫХ РЕЕК

The performing of high-precision geometric leveling by short beams with the purpose of control for the process of building and exploitation of engineering structures and industrial equipment is carried out with visual reading levels or digital levels in case there are a lot of disturbance effects, the basic of which are the vibrations of some equipment in operation, rapid temperature changes, and also non-sufficient and irregular light intensity of bar-code or lined rods. The purpose of the article is the improvement of high-precision leveling method performance by digital levels in the condition of insufficient light intensity of bar-code rods. The article considers the influence of insufficient light intensity of bar-code rods on the leveling station work by digital levels. Due to irregular and insufficient light intensity of the rod the receiver of the digital level does not allow to read distinctly the bar-code and to perform its processing and output to the indication unit in metric system. That’s why for accurate measurement on the station the light intensity of the rods should be sufficient, nearly similar and regular. The article gives the results of using the rod, equipped with light-emitting diodes to provide its sufficient and regular lighting.

Assessing dental light-curing units’ output using radiometers: A narrative review

Introduction:This review aimed to describe dental radiometers and discuss their effectiveness compared to other light-testing devices.Materials and Methods:The search for light-curing units (LCUs), radiometers, and other light-measuring tools available on the market was accomplished on data found on PubMed, Wikipedia, and Google.Results:LCUs are prone to deterioration due to several reasons such as the light’s limited life span, the worsening of the LCU’s filters, light guide, and light tip end; consequently, decreased photopolymerization and insufficient resin conversion may occur. A regular light output assessment is highly recommended in dental daily practice as well as before any new LCU purchase to make sure the light features meet the factory specifications delivered by the manufacturer and they remained stable through time.Discussion:Irradiance values reported by radiometers do not match accurately with those delivered by laboratory power meters. Therefore, dental practitioners as well as dental students are advised to control regularly every LCU by using the same handheld radiometer.

Preparation and cytotoxicity evaluation of hydrogels based on poly(trimethylene carbonate) and carboxyalkyl chitosans for regenerative medicine applications

Aim of this study was to assess possible influence of eight different variants of chitosan-based gels (without cross-linker treatment and cross-linked with one of the next substances – glutaraldehyde or hexamethylene diisocyanate) and poly(trimethylene carbonate) gels onto live tissues using in vitro cell culture model with 14 days incubation and regular light microscopy and final MTT cytotoxicity assay. All gel samples were preliminary undergone radiation sterilization with 25 kGy (equal to 10-6 sterility assurance level) absorbed dose before experiment.Results showed that four of eight tested gels showed mostly biocompatible behavior – both in cell culture and in MTT assay, except for hydrogel chitosan-hexamethylene diisocyanate and carboxyethylchitosan-1, and two poly(trimethylene carbonate) gel samples. For the poly(trimethylene carbonate) such negative results could be avoided in the future via modifications for increasing of hydrophilic properties and functionality, and for two worst chitosan-based gel samples a possible solution for the adequate cytotoxicity evaluation could be a more precision flow cytometry with known fluorescent cytotoxicity assays.

Non-contact physiological monitoring of preterm infants in the Neonatal Intensive Care Unit

The implementation of video-based non-contact technologies to monitor the vital signs of preterm infants in the hospital presents several challenges, such as the detection of the presence or the absence of a patient in the video frame, robustness to changes in lighting conditions, automated identification of suitable time periods and regions of interest from which vital signs can be estimated. We carried out a clinical study to evaluate the accuracy and the proportion of time that heart rate and respiratory rate can be estimated from preterm infants using only a video camera in a clinical environment, without interfering with regular patient care. A total of 426.6 h of video and reference vital signs were recorded for 90 sessions from 30 preterm infants in the Neonatal Intensive Care Unit (NICU) of the John Radcliffe Hospital in Oxford. Each preterm infant was recorded under regular ambient light during daytime for up to four consecutive days. We developed multi-task deep learning algorithms to automatically segment skin areas and to estimate vital signs only when the infant was present in the field of view of the video camera and no clinical interventions were undertaken. We propose signal quality assessment algorithms for both heart rate and respiratory rate to discriminate between clinically acceptable and noisy signals. The mean absolute error between the reference and camera-derived heart rates was 2.3 beats/min for over 76% of the time for which the reference and camera data were valid. The mean absolute error between the reference and camera-derived respiratory rate was 3.5 breaths/min for over 82% of the time. Accurate estimates of heart rate and respiratory rate could be derived for at least 90% of the time, if gaps of up to 30 seconds with no estimates were allowed.

IEEE 802.15.7-Compliant Ultra-Low Latency Relaying VLC System for Safety-Critical ITS

The integration of Visible-Light Communications technology (VLC) in Intelligent Transportation Systems (ITS) is a very promising platform for a cost-effective implementation of revolutionary ITS and cooperative ITS protocols. In this paper, we propose an infrastructure-to-vehicle-to-vehicle (I2V2V) VLC system for ITS, implementing it through a regular LED traffic light serving as a transmitter and a digital Active Decode-and-Relay (ADR) stage for decoding and relaying the received information towards further incoming units. The proposed VLC system targets the challenging and important case of ultra-low latency ADR transmission of short packets, as this is needed for emerging applications of automatic braking, car platooning and other critical automatic and/or assisted driving applications. The experimental validation of the ADR VLC chain, as well as a thorough statistical analysis of errors distribution in the transmission, has been performed for short to medium distances, up to 50 meters. The performances of the designed system are evaluated by measuring the packet error rate (PER) and latency in the whole ADR transmission chain. Our analysis shows that our system attains ultra-low, sub-ms latencies at 99.9\% confidence level for PER as high as $5\times10^{-3}$, yet granting a latency below 10 ms even for distances of 50 m. The demonstrated system prototype is compatible with IEEE 802.15.7 standard.

Onychoscopy with red light for vascular pattern identification: a study of 33 patients.

Nail dermoscopy (onychoscopy) during physical examination assists in correct diagnosis. Often further magnifications are necessary for an effective differential diagnosis. With the addition of a red light to the dermoscope, important vascular features can be visualized. To describe common features observed at onychoscopy with a new device that combines the regular white light with the red light illumination, demonstrating that it is useful for diagnosis of nail disorders. We enrolled 33 consecutive patients referred to the Nail Diseases Dermatology Unit of the University of Modena and Reggio Emilia and to the Outpatient Consultation for Nail Disease of the Dermatology Unit of the University of Bologna. Patients were assessed with a standard hand-held dermoscope and at the red light dermoscope. Dermoscopic images were collected. The new prototype was used during daily clinical practice and allowed a more accurate visualization of some details that classic onychoscopy can miss. In particular, with the help of the red light it was possible to better visualize nail lesions that were characterized by some kind of colour change or vascular alterations. The new device of red light for vascular pattern onychoscopy can be a new investigation method to observe nail alterations, especially due to vascular pattern, even with low magnification, without the necessity to use higher resolutions.

Supplementary UV radiation on eggplants indirectly deters Bemisia tabaci settlement without altering the predatory orientation of their biological control agents Nesidiocoris tenuis and Sphaerophoria rueppellii

Ultraviolet (UV) radiation that reaches the earth surface has increased substantially in the past decades, altering insect–plant interactions by directly affecting herbivores behavior or indirectly by modifying plant chemistry and morphogenesis. We evaluated the indirect effect of supplementary UV radiation under glasshouse conditions on Bemisia tabaci settlement, eggplant (Solanum melongena L.) production and its effects on the flight activity of Nesidiocoris tenuis and Sphaerophoria rueppellii. Eggplants were daily radiated with different supplemental UV treatments, A +/B +, A −/B + or A −/B −, during 30, 60 or 90 min for 21 days. The whitefly settlement was assessed immediately after the UV treatments or after 18 extra days on plants kept under regular glasshouse conditions with no further supplemental UV radiation. The number of whitefly settled on plants was counted after 2, 6, 24 and 48 h. Supplementary UV radiation reduced whitefly settlement for all exposure times with alterations on the morphology and increased nitrogen and amino acid content of eggplants, mainly after 90 min of UV radiation exposition. When plants were allowed to recover under regular light conditions, growth traits were similar, and whiteflies showed no preference. Fruit parameters were not negatively altered by supplementary UV radiation. Natural enemy captures per sticky trap were more abundant under A −/B + and A +/B + conditions; however, indirect host preference tests indicated no differences among treatments. In conclusion, supplementary UV radiation could be used to reduce whitefly infestation in glasshouses at the early stages of plant development without detrimental effects on crop yield or beneficial orientation.

Assessing Global DNA Methylation Changes Associated with Plasticity in Seven Highly Inbred Lines of Snapdragon Plants (Antirrhinum majus).

Genetic and epigenetic variations are commonly known to underlie phenotypic plastic responses to environmental cues. However, the role of epigenetic variation in plastic responses harboring ecological significance in nature remains to be assessed. The shade avoidance response (SAR) of plants is one of the most prevalent examples of phenotypic plasticity. It is a phenotypic syndrome including stem elongation and multiple other traits. Its ecological significance is widely acknowledged, and it can be adaptive in the presence of competition for light. Underlying genes and pathways were identified, but evidence for its epigenetic basis remains scarce. We used a proven and accessible approach at the population level and compared global DNA methylation between plants exposed to regular light and three different magnitudes of shade in seven highly inbred lines of snapdragon plants (Antirrhinum majus) grown in a greenhouse. Our results brought evidence of a strong SAR syndrome for which magnitude did not vary between lines. They also brought evidence that its magnitude was not associated with the global DNA methylation percentage for five of the six traits under study. The magnitude of stem elongation was significantly associated with global DNA demethylation. We discuss the limits of this approach and why caution must be taken with such results. In-depth approaches at the DNA sequence level will be necessary to better understand the molecular basis of the SAR syndrome.

Perspectives in affective disorders: Clocks and sleep.

Mood disorders are often characterised by alterations in circadian rhythms, sleep disturbances and seasonal exacerbation. Conversely, chronobiological treatments utilise zeitgebers for circadian rhythms such as light to improve mood and stabilise sleep, and manipulations of sleep timing and duration as rapid antidepressant modalities. Although sleep deprivation ("wake therapy") can act within hours, and its mood-elevating effects be maintained by regular morning light administration/medication/earlier sleep, it has not entered the regular guidelines for treating affective disorders as a first-line treatment. The hindrances to using chronotherapeutics may lie in their lack of patentability, few sponsors to carry out large multi-centre trials, non-reimbursement by medical insurance and their perceived difficulty or exotic "alternative" nature. Future use can be promoted by new technology (single-sample phase measurements, phone apps, movement and sleep trackers) that provides ambulatory documentation over long periods and feedback to therapist and patient. Light combinations with cognitive behavioural therapy and sleep hygiene practice may speed up and also maintain response. The urgent need for new antidepressants should hopefully lead to reconsideration and implementation of these non-pharmacological methods, as well as further clinical trials. We review the putative neurochemical mechanisms underlying the antidepressant effect of sleep deprivation and light therapy, and current knowledge linking clocks and sleep with affective disorders: neurotransmitter switching, stress and cortico-limbic reactivity, clock genes, cortical neuroplasticity, connectomics and neuroinflammation. Despite the complexity of multi-system mechanisms, more insight will lead to fine tuning and better application of circadian and sleep-related treatments of depression.

Chromogenic Tissue-Based Methods for Detection of Gene Amplifications (or Rearrangements) Combined with Protein Overexpression in Clinical Samples.

Immunohistochemistry (IHC) is a well-established, tissue-based assay for the visualization of target proteins. For analysis of DNA targets, chromogenic in situ hybridization (CISH) applications have significant advantages over traditional fluorescence in situ hybridization (FISH). CISH slides can be analyzed using a regular light microscope, while FISH slides require the use of a specialized fluorescence microscope in a dark room. CISH slides allow observers to correlate the gene status (gene amplifications, gene rearrangements, and gene deletions) in the context of tissue morphology better than FISH slides. Recently, a combination of IHC and CISH assays (gene-protein assay, GPA) was developed to study the relationship between gene status and protein expression on the same tissue section. CISH and GPA applications can be optimized using an automated tissue slide processing system to generate reproducible results for a long and complex assay protocol. GPA applications are an ideal approach for tumor status and heterogeneity analyses for research and clinical investigations.

A novel gold nanocomposite membrane with enhanced permeation, rejection and self-cleaning ability

The trade-off relationship between permeability, selectivity, and antifouling capability of nanocomposite membranes is the focal point of effective membrane technology. This study introduces a new gold nanocomposite membrane with enhanced antifouling behavior and permeability, as well as improved rejection capability for water treatment. Different (0.5, 1 and 2 wt%) concentrations of citrate-stabilized (coating) gold nanoparticles (CT-GNPs) having a core size of 50 nm were embedded into the polysulfone (PSF) membranes by the phase inversion method, resulting in alterations on PSF membrane performance. The intrinsic physicochemical properties and operational ability of all gold nanocomposite membranes were evaluated with regard to the self-cleaning, flux and selectivity criteria for water purification process. The PSF/0.5% GNPs demonstrated the optimal pore structure, morphology, and electrochemical surface properties among the gold nanocomposite and pure PSF membranes. The negative surface charge and the super hydrophilic functional group of CT-GNPs enhanced the permeation (at least three times in comparison with pure PSF membranes) and rejection ability of nanocomposite membranes. In addition, CT-GNPs showed digestive behavior towards humic acid (HA), a natural foulant, that significantly enhanced the antifouling ability (FRR = 95%) of the gold nanocomposite membranes by degrading the HA formed cake layer on the membrane surface and fragmenting the large HA aggregates that blocked the pores. The degradation of HA compounds by the embedded CT-GNPs occurred during the filtration process at room temperature and under the regular visible light. The stability of embedded GNPs into the polymeric matrix of membranes was evaluated at static and dynamic conditions for several days, and no release of CT-GNPs was observed.

Optical andJ, K-photometry of the quiescent black hole X-ray nova A0620−00 in the passive and active states

Photometric observations of the low-mass X-ray binary system A0620-00=V616 Mon are performed in the optical (unfiltered light, lambda_eff~6400A) and the near-infrared J and K-bands. The mean system flux, the orbital light curve shape and the flickering amplitude dependences on wavelength are examined for two activity stages of the system remaining in quiescence. In 2015-16 A0620-00 was in passive stage (as by Cantrell et al., 2008) exhibiting the regular orbital light curves and low flickering. In less than 230 days in 2016-17 the system switched into active stage: the brightness increased by ~0.2-0.3 mag, the orbital light curve changed while the flickering amplitude increased more than twice. The object regular orbital light curves were fitted by models with "cold" spots on the optical star surface and without those. These models reproduce the observed orbital light curves both in passive and in active stages. The dependence of the mean square flickering amplitude (in fluxes, extinction corrected) on wavelength is computed in the lambda 6400-22000AA range. In active stage, the observed flickering amplitude decreases over the whole studied range and may be represented as Delta F_fl~lambda^{-2} which corresponds to the free-free emission of optically thin high-temperature plasma. In passive stage, flickering obeys Delta F_fl~lambda^{-4} law in the range 6400-12500AA that corresponds to the thermal radiation of optically thick high-temperature plasma. At longer wavelengths the flickering amplitude dependence is flat which may imply existence of a synchrotron component of the relativistic jets emission. These flickering features let us propose that the flickering mechanism includes at least two components: thermal and, apparently, synchrotron, that agrees with the recent discovery of the variable linear polarization of the IR system emission (Russell et al., 2016).

Tuning phosphors for better white light

“Incandescent bulbs are one of the most energy-inefficient products in daily use,” Joanna McKittrick says. Touch a regular old 100-W light bulb after it’s been lit for a few minutes, and you’ll see what she means. Less than 5% of the electrical energy that goes into the tungsten filament inside is converted to visible light, explains McKittrick, a luminescent materials specialist at the University of California, San Diego. The rest is wasted as heat that, should you follow our instructions, will burn your fingers. Incandescents “basically haven’t changed since Thomas Edison invented them” about 140 years ago, she says. Bulbs that contain light-emitting diodes (LEDs), on the other hand, can produce the same amount of white light but barely feel warm to the touch. That’s because LEDs are more energy efficient. A 15-to-20-W LED can produce the same brightness as a 100-W incandescent, roughly 1,500 lumens. LEDs are also less

Physical activity and mortality in patients with stable coronary heart disease.

To review recent literature on associations between habitual physical activity and mortality in general populations and patients with stable coronary heart disease. There are substantial decreases in cardiovascular and all-cause mortality between people who take little or no exercise and those who take regular light or moderate physical activity. The benefits associated with increasing high-intensity exercise are smaller, and an increase in mortality risk is possible. Meta-analyses of trials of exercise-based cardiac rehabilitation suggest a small mortality benefit from supervised exercise training, but because of a high risk of bias, the impact on cardiovascular mortality and hospitalizations is uncertain. Modest habitual physical activity is likely to lower mortality in most patients with stable coronary heart disease.

In-Use Photostability Practice and Regulatory Evaluation for Pharmaceutical Products in an Age of Light-Emitting Diode Light Sources

This article describes how the increased use of energy-efficient solid-state light sources (e.g., light-emitting diode [LED]-based illumination) in hospitals, pharmacies, and at home can help alleviate concerns of photodegradation for pharmaceuticals. LED light sources, unlike fluorescent ones, do not have spurious spectral contributions <400 nm. Because photostability is primarily evaluated in the International Council of Harmonization Q1B tests with older fluorescent bulb standards (International Organization for Standardization 10977), the amount of photodegradation observed can over-predict what happens in reality, as products are increasingly being stored and used in environments fitted with LED bulbs. Because photodegradation is premised on light absorption by a compound of interest (or a photosensitizer), one can use the overlap between the spectral distribution of a light source and the absorption spectra of a given compound to estimate if photodegradation is a possibility. Based on the absorption spectra of a sample of 150 pharmaceutical compounds in development, only 15% would meet the required overlap to be a candidate to undergo direct photodegradation in the presence of LED lights, against a baseline of 55% of compounds that would, when considering regular fluorescent lights. Biological drug products such as peptides and monoclonal antibodies are also expected to benefit from the use of more efficient solid-state lighting.

Spatial and spectral illumination design for energy-efficient circadian lighting

Daily light-dark patterns incident on human eyes play an important role in maintaining a healthy circadian rhythm. The lack of daytime light in indoor spaces could negatively impact the occupants’ health and well-being in the long term. Therefore, applying circadian lighting in certain built environments is attractive.In this work, we introduce innovative methods for circadian lighting design and investigate the potential of efficacy improvement by comparing these methods with traditional lighting design approaches. For the spatial aspect, we show that the regular lighting design approach focusing on horizontal workplane illuminance could lead to a very inefficient delivery of indirect corneal illuminance compared with the proposed method of distributing initial flux to a highly reflective room surface; for the spectral aspect, it is shown that the traditional approach of pursuing high luminous efficacy could potentially lead to the worst-case scenario for circadian efficacy based on a four-component color-mixing analysis. Two leading spectral sensitivity models for the circadian system (i.e., the CLA model and the EML model) are compared, each of which leads to different trends of spectral circadian efficacy versus color temperature but the same strategy for spectral optimization. Based on the analysis in both the spatial and spectral aspects, a framework of efficient circadian lighting solutions is proposed to guide new good lighting design with health benefits. It is shown that the proposed new approaches can potentially improve the overall circadian lighting efficacy by up to 3.6 times.

Preparation and Assessment of Heat-Treated α-Chitin Nanowhiskers Reinforced Poly(viny alcohol) Film for Packaging Application.

In this study, poly(vinyl alcohol) (PVA) composite films enhanced by α-chitin nanowhiskers (ChWs) were prepared through heat treatment. The obtained membranes were assessed by means of FTIR spectroscopy, X-ray diffraction, thermogravimetric analysis, regular light transmittance, mechanical tests, permeability and water absorption. The influence of the nano-component and heat treatment on the mechanical, thermal and water-resistant properties of the composite membrane were analyzed. From the results of the work, the produced films with excellent barrier properties and inexpensive raw processed materials have great prospects in packaging applications.

Effect of dynamic light at the coronary care unit on the length of hospital stay and development of delirium: a retrospective cohort study.

BackgroundDisturbed circadian rhythm is a potential cause of delirium and is linked to disorganisation of the circadian rhythmicity. Dynamic light (DL) could reset the circadian rhythm by activation of the suprachiasmatic nucleus to prevent delirium. Evidence regarding the effects of light therapy is predominantly focused on psychiatric disorders and circadian rhythm sleep disorders. In this study, we investigated the effect of DL on the total hospital length of stay (LOS) and occurrence of delirium in patients admitted to the Coronary Care Unit (CCU).MethodsThis was a retrospective cohort study. Patients older than 18 years, who were hospitalized longer than 12 h at the CCU and had a total hospital LOS for at least 24 h, were included. Patients were assigned to a room with DL (n = 369) or regular lighting conditions (n = 379). DL was administered at the CCU by two ceiling-mounted light panels delivering light with a colour temperature between 2700 and 6500 degrees Kelvin. Reported outcome data were: total hospital LOS, delirium incidence, consultation of a geriatrician and the amount of prescripted antipsychotics.ResultsBetween May 2015 and May 2016, data from 748 patients were collected. Baseline characteristics, including risk factors provoking delirium, were equal in both groups. Median total hospital LOS in the DL group was 100.5 (70.8–186.0) and 101.0 (73.0–176.4) h in the control group (P = 0.935). The incidence of delirium in the DL and control group was 5.4% (20/369) and 5.0% (19/379), respectively (P = 0.802). No significant differences between the DL and control group were observed in secondary endpoints. Subgroup analysis based on age and CCU LOS also showed no differences.ConclusionOur study suggests exposure to DL as an early single approach does not result in a reduction of total hospital LOS or reduced incidence of delirium. When delirium was diagnosed, it was associated with poor hospital outcome.

An optogenetic approach to control protein localization during embryogenesis of the sea urchin

Light inducible protein–protein interactions have been used to manipulate protein localization and function in the cell with utmost spatial and temporal precision. In this technical report, we use a recently developed optogenetic approach to manipulate protein localization in the developing sea urchin embryo. A photosensitive LOV domain from Avena sativa phototropin1 cages a small peptide that binds the engineered PDZ domain (ePDZ) upon blue light irradiation. Using this system, mCherry tagged proteins fused with the LOV domain were recruited to ectopic sub-cellular regions such as the membrane, microtubules, or actin by GFP tagged proteins fused with the ePDZ domain upon blue light irradiation within 1–3 min in the sea urchin embryo. The efficiency and speed of recruitment of each protein to its respective subcellular region appeared to be dependent on the power and duration of laser irradiation, as well as the respective level of affinity to the tagged location. Controlled laser irradiation allowed partial recruitment of the spindle to the membrane, and resulted in cell blebbing. Vasa, a cell cycle and germline factor that localizes on the spindle and enriches in the micromeres at 8–16 cell stage was recruited to ectopic sites, preventing normal enrichment. Continuous blue light activation with a regular blue aquarium light over two days of culture successfully induced LOV-ePDZ binding in the developing embryos, resulting in continued ectopic recruitment of Vasa and failure in gastrulation at Day 2. Although some cytotoxicity was observed with prolonged blue light irradiation, this optogenetic system provides a promising approach to test the sub-cellular activities of developmental factors, as well as to alter protein localization and development during embryogenesis.