Light Filters Research Articles

Development of NLC- based Sunscreen Gel of Lutein and its in-vitro and ex-vivo Characterisation

Background: In humans, Carotenoids are important in scavenging singlet oxygen and peroxyl radicals. Lutein has been demonstrated in multiple studies to help protect the skin from photodamage, as well as provide a variety of other health advantages. In the recent decade, the topi-cal use of Lutein as a new ultraviolet (UV) protectant, anti-stress, and blue light filter capable of protecting skin from photodamage has piqued cosmetic and pharmacological attention. Because Lutein is insoluble, it was integrated into nanocarriers for topical administration. Objective: The objective of this study was to formulate an NLC-based sunscreen gel of Lutein. Method: Nanostructured lipid carriers (NLC) were prepared by melt emulsion ultrafiltration tech-nique and were evaluated for particle size, zeta potential, polydispersity index (PDI), drug loading (DL), encapsulation efficacy (EE), and in vitro drug release. The optimised formula was incorpo-rated into a gel base and an in-vitro sun protection factor (SPF) was determined. Ex- vivo permea-tion study was performed on rat skin using a Franz diffusion cell. Cocoa butter and rose oil were chosen as solid and liquid lipids for NLC formulation. Results: The particle size, PDI, zeta potential, entrapment efficiency, and in vitro drug release of optimised formulation (NLC5) were found to be 81.64 nm, 0.463, -14.1mV, 79.90 %, and 89.86% respectively. The SPF value of the Lutein-NLC-loaded gel was found to be 27.524. The drug flux Jss from NLC gel was measured in the range of 0.07955 g/cm2/h. Conclusion: The investigation suggested lipid nanoparticles as a suitable carrier for Lutein to be delivered as sunscreen gel.

Evaluation of the chemical, cytological and bacteriological compositions of surgical smoke and evaluation of purification of smoke by ultraviolet light and various filters in laparoscopic surgeries

Background: The present study aimed to assess the cytological, bacterial and chemical composition of laparoscopic surgical smoke and the evaluation of purification of surgical smoke by smoke purifying device containing ultraviolet (UV) light and various filters. Methods: Sixty patients undergoing laparoscopic abdominal surgery lasting >45 min were included in this randomized controlled study. The patients were divided into two groups: group A-smoke passing through smoke purifying device and group B-smoke without passing through smoke purifying device. Sample for cytological, bacteriological and chemical analysis were collected from both the groups. The primary outcome measures were to find the cytological, bacteriological and chemical composition of surgical smoke. The secondary outcome measure was evaluation of purification of surgical smoke by smoke purifying device containing ultraviolet light and various filters. Intergroup comparison of categorical and continuous variables was done using the Chi square test/Fisher’s exact test and unpaired t test respectively. Results: The present study shows the group A wherein smoke evacuating device containing various filters were used has no bacterial growth as well as no cells seen on cytological evaluation as compared to the group B wherein 21/30 (70.0%) cases had few lymphocytes and 3/30 (10.0%) cases had coagulase-negative Staphylococci wherein smoke evacuation device was not used. However, the chemical composition was comparable in both the groups. Conclusions: The smoke evacuation and filtration device, filtrates and clears the smoke of cells and bacteria as it passes through it.

Emotional responses of college students to filtered fluorescent lighting in a classroom (v3).

Classroom lighting, usually bright fluorescent light, can significantly influence the learning environment and emotions of students. To assess the emotional impact of classroom lighting on students during an academic year. This study used an ABAB withdrawal research design in the following manner: in phase A, the baseline condition, classroom lighting was provided by conventional overhead white fluorescent classroom lights; in phase B, the intervention condition, the conventional overhead white fluorescent classroom lights were covered with fabric filters (thin, translucent, creamy-colored plastic sheets) that were attached to the lighting fixture frame with magnetic discs. The filters produced softer light in the classroom than the fluorescent lights. Each phase lasted for at least 2 weeks. During each phase, students rated 18 pairs of words from the Mehrabian and Russell pleasure, arousal, and dominance semantic differential scale at least four times to assess the emotional impact of the lighting conditions. For all three emotional behaviors, the mean score of the filtered fluorescent light phase was significantly greater than the mean score of the baseline unfiltered fluorescent lighting phase, indicating more positive emotional responses. Students also noted they experienced fewer headaches and found it easier to see the whiteboard at the front of the classroom when the light filters were in place. The light filters exerted a positive impact on the students' emotions. Students preferred the filtered lighting to fluorescent lighting. This study supports the installation of filters over fluorescent lights in a college classroom.

Properties of Dyes for Painting with Spectroscopy in the Visible and Near Infrared Range

This study focuses on the properties of reflection and absorption of light in the visible and near infrared range of acrylic dyes and related materials for coloring. The research aims to understand the use of acrylic dyes in fine arts and to simulate these dyes for printing purposes. Two groups of acrylic dyes were studied using spectroscopy to determine their light absorption properties in the visible (VIS) and near infrared (NIR) regions. The measurements were performed with forensic cameras equipped with 24 light filters in the range of 400–1000 nm. The results of the digital recordings were compared with video surveillance cameras that operate and record during the day and night. The same color had at least two formulations of dyes for print reproduction to simulate what the naked eye sees and to simulate light absorption in the NIR spectrum. The study aimed to gain a deeper understanding of the properties of acrylic paints and related materials, considering how they can be used in fine arts and how to simulate them in printing.

Intraoperative Fluorescein Sodium in Pediatric Neurosurgery: A Preliminary Case Series from a Singapore Children's Hospital.

(1) Background: Fluorescein sodium (Na-Fl) has been described as a safe and useful neurosurgical adjunct in adult neurooncology. However, its use has yet to be fully established in children. We designed a study to investigate the use of intraoperative Na-Fl in pediatric brain tumor surgery. (2) Methods: This is a single-institution study for pediatric brain tumor patients managed by the Neurosurgical Service, KK Women's and Children's Hospital. Inclusion criteria consists of patients undergoing surgery for suspected brain tumors from 3 to 19 years old. A predefined intravenous dose of 2 mg/kg of 10% Na-Fl is administered per patient. Following craniotomy, surgery is performed under alternating white light and YELLOW-560 nm filter illumination. (3) Results: A total of 21 patients with suspected brain tumours were included. Median age was 12.1 years old. For three patients (14.3%), there was no significant Na-Fl fluorescence detected and their final histologies reported a cavernoma and two radiation-induced high grade gliomas. The remaining patients (85.7%) had adequate intraoperative fluorescence for their lesions. No adverse side effects were encountered with the use of Na-Fl. (4) Conclusions: Preliminary findings demonstrate the safe and efficacious use of intraoperative Na-Fl for brain tumors as a neurosurgical adjunct in our pediatric patients.

Optimization of novel exoscopic blue light filter during fluorescence-guided resection of Glioblastoma.

Operative guidelines and use optimization for new surgical exoscopes are not well described in the literature. In this study, we evaluated use of the ORBEYE (Olympus) surgical exoscope system during 5-ALA fluorescence-guided resection of GBMs to optimize workflow and exoscope settings. The ORBEYE exoscope system was fitted with a blue light filter for 5-ALA mediated fluorescence-guided surgery (FGS). Intraoperative images were obtained during 5-ALA FGS in 9 patients with primary or recurrent GBM. The exoscope was set up at constant, increasing focal distances from the target tissue, and light source intensity varied. High-resolution 4K images were captured and analyzed. Comparisons of fluorescence to background were then generated for use optimization. Light intensity did not significantly influence tumor fluorescence (P = 0.878). However, focal distance significantly impacted relative fluorescent intensity (P = 0.007). Maximum average fluorescence was seen consistently at a focal length of 220mm and a light intensity of approximately 75% maximum. Decreasing focal distance from 400mm to 220mm significantly increased visualized fluorescence (P = 0.0038). The ORBEYE surgical exoscope system with blue light filter is a powerful imaging tool for 5-ALA FGS in GBM. The ORBEYE blue filter performs optimally at shorter focal distance with moderate light intensity. Similar to microscope systems, decreasing focal distance significantly influences visualized fluorescence.

The association between altered intestinal microbiome, impaired systemic and ocular surface immunity, and impaired wound healing response after corneal alkaline-chemical injury in diabetic mice.

We aim to investigate the effect of sustained hyperglycemia on corneal epithelial wound healing, ocular surface and systemic immune response, and microbiome indices in diabetic mice compared to controls after alkaline chemical injury of the eye. Corneal alkaline injury was induced in the right eye of Ins2Akita (Akita) mice and wild-type mice. The groups were observed at baseline and subsequently days 0, 3, and 7 after injury. Corneal re-epithelialization was observed under slit lamp with fluorescein staining using a cobalt blue light filter. Enucleated cornea specimens were compared at baseline and after injury for changes in cornea thickness under hematoxylin and eosin staining. Tear cytokine and growth factor levels were measured using protein microarray assay and compared between groups and time points. Flow cytometry was conducted on peripheral blood and ocular surface samples to determine CD3+CD4+ cell count. Fecal samples were collected, and gut microbiota composition and diversity pattern were measured using shotgun sequencing. Akita mice had significantly delayed corneal wound healing compared to controls. This was associated with a reduction in tear levels of vascular endothelial growth factor A, angiopoietin 2, and insulin growth factor 1 on days 0, 3, and 7 after injury. Furthermore, there was a distinct lack of upregulation of peripheral blood and ocular surface CD3+CD4+ cell counts in response to injury in Akita mice compared to controls. This was associated with a reduction in intestinal microbiome diversity indices in Akita mice compared to controls after injury. Specifically, there was a lower abundance of Firmicutes bacterium M10-2 in Akita mice compared to controls after injury. In diabetic mice, impaired cornea wound healing was associated with an inability to mount systemic and local immune response to ocular chemical injury. Baseline and post-injury differences in intestinal microbial diversity and abundance patterns between diabetic mice and controls may potentially play a role in this altered response.

Compact Fluorescence Detection System Based on a Monolithic DBR-Integrated III-Nitride LED Chip.

Portable applications of fluorescence detection systems have gained much attention in various fields and require system components to be small and compact. In this work, we report on a compact fluorescence detection system and demonstrate its application for fluorescence sensing and imaging. The light source and filter are integrated on a single chip for the proposed system, which not only realizes the separation between excitation and fluorescent lights but also improves the light-emitting diode (LED) light extraction efficiency. Furthermore, the detection system allows for a removable sample unit. The results indicate that the performance of the distributed Bragg reflector (DBR) filter based on an amorphous dielectric film is excellent with selection ratios larger than 4600:1. The peak emission wavelength of the LED is 528 nm. The influence of green light leakage can be neglected, and the fluorescent red light is dominant when the fluorescence detection system is used for sensing and imaging. The low-cost and monolithic DBR-integrated III-nitride LED chip makes the proposed architecture a competitive candidate for portable fluorescence detection applications.

Suppressing optical crosstalk for GaN/InGaN based flip-chip micro light-emitting diodes by using an air-cavity patterned sapphire substrate as a light filter.

In this work, by using three-dimensional finite-difference time-domain (3D FDTD) method, the effect of conventional nano-patterned sapphire substrate (NPSS) on the optical crosstalk and the light extraction efficiency (LEE) for InGaN/GaN-based flip-chip micro light-emitting diodes (µ-LEDs) are systematically studied. We find that the conventional NPSS is not suitable for µ-LEDs. It is because the inclined mesa sidewall for µ-LEDs possesses a good scattering effect for µ-LEDs, but the introduced conventional NPSS causes part of the light be off escape cone between sapphire and air and become the guided light. To suppress the guided light and improve the optical crosstalk, a thick air layer between the n-GaN layer and the sapphire substrate can be used as a light filter to prevent the guided light from propagating into the sapphire. However, in reality, it is challenging to make the aforementioned air layer from point of fabrication view. Therefore, we propose the air-cavity patterned sapphire substrate (AC-PSS) as the light filter. Our results show that the crosstalk ratio can be decreased to the value even lower than 10%. The LEE can also be enhanced simultaneously due to combination effects of the filtering effect of the AC-PSS and the scattering effect of the inclined mesa sidewall.

A retinomorphic neuron for artificial vision and iris accommodation.

The iris of an eye automatically optimizes the amount of light that strikes the retina by accommodating the intensity of ambient light. Here, we describe a retinomorphic neuron using neuromorphic photoreceptors for artificial vision and iris accommodation that mimics the biological structure and processing functions of retinal neurons for light sensing and signal transduction. The system consists of a neuromorphic photoreceptor, an electrochromic device as a light filter, and a spike-generation unit. In particular, the Au nanoparticle (NP) decorated ITO fiber photoreceptor with a well-aligned array structure is able to rely on its own light-tunable synaptic plasticity and the plasmon-enhanced light absorption. Therefore, it allows real-time feedback about light intensity, emits a higher-frequency electrical stimulus to stronger light, flash, or prolonged light illumination time, and drives the electrochromic filter to work, allowing mild light to pass through. Compared with traditional artificial irises or artificial photoreceptors, our design introduces neural pathways and neuromorphic devices, which are closer to biological functions in simulation. To our knowledge, this is the first time that a retinal neuron with neuromorphic photoreceptors has been used for artificial iris vision. Furthermore, we demonstrate direct and consensual pupillary light reflexes. The design of artificial iris vision has potential applications in biomimetic engineering, smart interaction, and visual prostheses.

"Glow ELISA": sensitive immunoassay with minimal equipment and stable reagents.

Glow enzyme-linked immunosorbent assay (glow ELISA) uses inexpensive and shelf-stable glow stick reagents to chemically excite fluorescent reporters, obviating the need for excitation light sources, filters, and complex optics. It achieves excellent limits of detection while offering portability and equipment cost comparable to lateral flow immunoassays.

A brief review on biological and chemical activities of flavonoids in plants

Flavonoids are a group of plant pigments, the combination of which determines one or another color of flowers and fruits. In plants, flavonoid dyes play the role of light filters that protect tissues from negative influences. Flavonoids are widely distributed secondary metabolites with different metabolic functions in plants. Flavonoids - a group of polyphenolic compounds C6-C3-C6 -series that are synthesized exclusively in higher plants. This review considers four main functions of flavonoids in the plant body. These compounds take an active part in redox processes, in plant reproduction they play the role of bright attractants for insects and animals. An important function of flavonoids is to protect plants from external adverse abiotic and biotic factors. They are signal molecules in auxin metabolism, as well as at various stages of the plant symbiosis with mycorrhizal fungi and nitrogen-fixing bacteria.

Digital device-related eye health awareness among the engineering fraternity

ABSTRACT Purpose: The spectrum of symptoms that arise from prolonged hours of computer work has been the focus of interest since computers became the center of the modern workplace. This study focuses on engineers and aims at identifying the departments that are most susceptible to the effects of computer vision syndrome (CVS), their awareness about the entity, and identify lacunae in the existing eye health education provided to them. Materials and Methods: A cross-sectional study was conducted through an open online survey that was circulated among engineering college students belonging to colleges in Southern India and working professionals in the Information Technology (IT) and non-IT sector from the Southern States of India. Responses were collected over a period of 5 weeks spanning over 2 months and analyzed using the SPSS software version 25. Results: A total of 449 usable responses were received. The professionals in the non-IT sector logged a daily average work-related computer usage of 3.9 ± 3.1 h/day, while the IT sector professionals logged 4.3 ± 3.2 h/day of work-related computer usage. Among the participants, 57% of the study population were unaware of an entity called CVS, and 74.6% believed that blue light filters prevented damage caused by prolonged screen time. The data showed that 18% of the study population have never undergone an ophthalmic evaluation. Conclusion: It is evident that no health education is available to engineers at any stage of their professional career that helps them deal with ocular effects of prolonged screen time. We would like to recommend an ophthalmic screening and eye-heath awareness program to be conducted at the time of recruitment, with refresher courses at timely intervals.

СПЕКТРАЛЬНЫЙ АНАЛИЗ КАК ИНСТРУМЕНТ ОПРЕДЕЛЕНИЯ КАЧЕСТВА СМЕШИВАНИЯ МНОГОКОМПОНЕНТНОЙ КОРМОВОЙ СМЕСИ

In this paper, it is proposed to develop the theoretical foundations of spectral analysis of the quality of mixing feed components in various types of cooking and distribution machines. A camera equipped with a set of corrective light filters, a device containing a radiation source (excitation) and photodetectors, was developed and manufactured to conduct economic tests and test the scientific hypothesis. The number and size of objects obtained from the device on the binarized image allow us to judge the uniformity of mixing of the feed mixture. Qualitative assessment of indicators of features is reduced to the definition of clouds of points of objects (compound feed) and the calculation of their area. During the control of the mixing process of concentrated compound feed and coarse feed, the ratio of spectral characteristics increases, while the evaluation of the index Φ = f (ms, mk) allows you to build a map of the binarized image, where objects with a high content of chlorophyll (coarse feed) are highlighted in black, which absorb the radiation source, and concentrated compound feed is highlighted in white. The uniformity of distribution of the concentrated components of the feed mixture in the rough was evaluated by analyzing the binarized image map, while the maximum level of discrepancy in the analyzed samples was 5 % relative to the actual one.

ВИЗУАЛИЗАЦИЯ ГОРЕНИЯ НАНОПОРОШКОВ МЕТАЛЛОВ СПРИМЕНЕНИЕМ ИМПУЛЬСНОГО И НЕПРЕРЫВНОГО ЛАЗЕРОВ ПОДСВЕТКИ

The work is devoted to the development of the method for high-speed imaging of high-temperature combustion processes using laser illumination. The object of visualization was a sample of aluminum nanopowder, which combustion temperature reaches 2500 K and is accompanied by a bright glow that varies in a wide range during combustion. It is demonstrated that laser illumination expands the capabilities of a high-speed imaging system and allows a more detailed study of the surface of samples compared to passive imaging by installing a neutral or band-pass filter in front of the high-speed camera lens. Various options for imaging with the installation of light filters with different transmission are considered. To monitor the surface of a burning material with a high-speed video camera in a wide temperature range of an object, it is proposed to use a low-power illumination from a continuous wave solid-state laser or a pulsed laser, as well as a beam expander for uniform illumination of the surface. The results of imaging using illumination from a solid-state laser with a wavelength of 532 nm and a copper bromide vapor laser with a wavelength of 510.6 nm are compared. It is shown that the output power of a solid-state laser of 200 mW with an illumination area diameter of 20 mm is sufficient to visualize “through the flame” the surface of a burning aluminum nanopowder at a low-temperature stage of combustion up to temperatures of ~1950 K. The uniform illumination of the surface can be ensured both by using a diffuser located directly near the sample, and with the use of a telescopic beam expander. Theoretical estimates and experimental results demonstrate that the illumination average power of 200 mW, regardless of the type of laser, is not enough to visualize the surface of a burning aluminum nanopowder at the high-temperature stage. The possibility of complete suppression of illumination during combustion with a temperature above 2500 K will appear when using an illumination laser with an average power of >3,35 W. The proposed illumination technique based on a solid-state laser has advantages in terms of reliability and simplicity compared to known systems based on copper or copper bromide vapor lasers.

An Improved Method to Obtain Fish Weight Using Machine Learning and NIR Camera with Haar Cascade Classifier

The calculation of weight and mass in aquaculture systems is of great importance, since with this task, it is decided when to harvest; generally, the above is manipulating the body manually, which causes stress in the fish body. Said stress can be maintained in the fish body for several hours. To solve this problem an improved method was implemented using artificial intelligence, near-infrared spectroscopy camera, Haar classifiers, and a mathematical model. Hardware and software were designed to get a photograph of the fish in its environment in real conditions. This work aimed to obtain fish weight and fish length in real conditions to avoid the manipulation of fish with hands for the process mentioned, avoiding fish stress, and reducing the time for these tasks. With the implemented hardware and software adding an infrared light and pass band filter for the camera successfully, the fish was detected automatically, and the fish weight and length were calculated moreover the future weight was estimated.

The effect of testosterone on Сa<sup>2+</sup> release stimulated by somatotropin and theophylline from intracellular stores of <i>Sus Scrofa Domesticus</i> oocytes

Purpose. Studying the influence of testosterone on stimulated by somatotropin and theophylline liberation of Ca2+ from intracellular depot of oocytes of pigs.Materials and methods. The material for the studies was oocytes secreted from antral follicles (with a diameter of 3-6 mm) of the ovarian Sus Scrofa domesticus. Oocyte complexes were aspirated from the ovaries at the stage of follicular growth, without signs of visible pathology. The dedicated oocytes were incubated in the modified incubation environment Dulbekko without CaCl2, containing 36 mg/l of Piruvat NA and 1 g/l glucose. Caicium in the intracellular depot of oocytes of pigs was measured with the help of a chlortetracycline (CTC) fluorescent probe. Oocytes were loaded with a probe for 5 minutes at 370C in an environment containing 40 microns of CTC. Then the cells were washed three times in an incubation environment and transferred to a special quartz glass with cells of 0.05 ml. Dependent on Ca2+ fluorescence of the CTC was recorded in oocytes in the environment of Dulbekko. The intensity of the fluorescence of the CTC probe was measured on a fluorimetric installation consisting of a fluorescent microscope, equipped with the necessary light filters and a photometric nozzle of the FMEL-1A. The CTC-Ca2+complex-the membrane excited 380-400 nm light, fluorescence was recorded in the area of 530 nm. The intensity of fluorescence was measured in the conc. units. The duration of ultraviolet radiation on oocytes during measurements did not exceed 5 seconds. In all experiments, an EGT was added to the incubation environment at a concentration of 0.5 mm.Results. It was shown that in the absence of testosterone in oocytes, the addition of somatotropin (bST) or theophylline stimulated the release of Ca2+ from intracellular depot, while their joint action did not lead to an additional exit of Ca2+ from intracellular depot. Inhibition of proteinkinase and did not affect the liberation of Ca2+, stimulated separately by bST or Theophylline, as well as their joint action. Against the background of the use of testosterone, the addition of bST or theophylline separately did not lead to the release of Ca2+ from intracellular depot. With the joint action of bST and Theophylline in the presence of testosterone, the liberation of Ca2+ from intracellular depot was noted, and the value of this indicator was higher than with the joint action of bST and Theophylline in the absence of testosterone. In stimulated by the joint action of bST and theophylline, the release of Ca2+ from the intracellular depot of oocytes in the presence of testosterone is participated in proteinquinase A and microfilaments, since when exposed to proteinquine A and polymerization of cytochalazine microfilaments release of Ca2+ from intracellular depots was not recorded.

Accurate Underwater Optical Wireless Communication Model With Both Line-of-Sight and Non-Line-of-Sight Channels

Underwater optical wireless communication (UOWC) systems have been widely studied to achieve high-speed wireless communications. To investigate and design UOWC systems, a mathematical model to characterize the accurate performance of UOWC systems is important. However, the previous mathematical models of UOWC systems have limitations, which mainly focused on the line-of-sight (LOS) link, and only considered the vertical incident background light or optical filters with constant transmittance for simplicity. To overcome these limitations, we establish an accurate UOWC system model, incorporating the previously overlooked impact of signal and sun lights incident angles and including both LOS and non-line-of-sight (NLOS) channels. Our proposed accurate UOWC system model is validated by Monte Carlo (MC) simulations. Results show that our proposed model can capture the changes of received powers of both signal and background lights with various transmitter and receiver alignments and orientations in both LOS and NLOS channels, which typically affect the signal-noise-ratio (SNR) and bit-error-rate (BER) performance of UOWC systems. Furthermore, we show that the incident angles of both signal and sun lights have significant impact on the system performance, and our proposed model can be used to optimize the PD rotation angle to improve the SNR performance. Therefore, the more accurate UOWC channel model established in this paper provides a fundamental framework for future UOWC system design and optimization.

Characterization of pulsed light for microbial inactivation

Pulsed light is an emerging technology that can serve as an alternative to current antimicrobial interventions in the food industry. The first objective of this study was to define the spectrum and energy characteristics of pulsed light. The second objective was to establish the germicidal response of Escherichia coli , Salmonella enterica subsp. enterica ser. Typhimurium, Listeria monocytogenes , Bacillus cereus (vegetative cells and endospores), Aspergillus niger spores, and Penicillium roqueforti spores were evaluated following pulsed light treatments. Microorganisms were treated using three different broad-spectrum xenon gas flashlamps (Type A: 380–1100 nm, Type B: 235–1100 nm, and Type C: 190–1100 nm) for up to 15 pulses. All microorganisms experienced a significant interaction of flashlamp type × treatment duration (P < 0.0001). Additionally, E. coli was treated with pulsed light with flashlamp type B using light filters to block ultraviolet light and selectively deliver visible (VIS; 380–740 nm), near-infrared (NIR; 700–1080 nm), and VIS-NIR (400–1080 nm) radiation to the cells. The filter type × treatment duration interaction was significant (P < 0.0001). The VIS, NIR, and VIS-NIR filter treatments achieved modest reductions of 0.72, 0.19, and 0.83 Log 10 CFU/mL, respectively, after 75 consecutive pulses. To visualize physical effects on cell structures, transmission electron microscopy (TEM) images were obtained for E. coli following 15 pulse treatments of the three flashlamp types and the type B flashlamp with VIS-NIR filter placement. TEM imaging indicated that damage to cell morphology following treatment by broad-spectrum radiation was negligible. These results indicate that microbial sensitivity to pulsed light treatment differs for species and is predominantly attributed to the ultraviolet portion of the spectrum. • Pulsed light treatment susceptibility differs for Gram -, Gram +, and spores/fungi. • Microbial inactivation by pulsed light is predominantly attributed to UV light. • Visible and near-infrared radiation contribute negligibly to microbe inactivation. • Pulsed light treatment imparts negligible effects to Escherichia coli morphology.

A Comparative Analysis with Exoscope and Optical Microscope for Intraoperative Visualization and Surgical Workflow in 5-Aminolevulinic Acid–Guided Resection of High-Grade Gliomas

The exoscope has been proposed as a valid tool in 5-aminolevulinic acid-guided resection of high-grade gliomas. However, it is not clear if, beyond ergonomics, the exoscope provides a real benefit over the optical microscope (OM). The aim of this study was to compare the exoscope with the OM in terms of surgical visualization and workflow in 5-aminolevulinic acid-guided brain surgery. Surgical videos of patients diagnosed with histopathologically confirmed, Shinoda stage I, high-grade gliomas who underwent surgery in from January to April 2022 were studied. Visualization under a 5-aminolevulinic acid blue filter for vessels, parenchyma, surgical instruments, and fluorescence was categorized for both superficial and deep fields. The following data were also recorded: median number of switches between white light and blue filter, average duration per switch, and amount of work under blue filter. There were 5 surgeries performed under OM guidance and 5 performed under exoscope guidance. Under a blue filter, the exoscope was significantly better than the OM in visualizing vessels, parenchyma, and surgical instruments for both superficial and deep surgical fields. The median number of switches between blue and white light was lower compared with the OM. Both median switch duration and percentage of work under the blue filter were superior when using the exoscope. Within the limitations of a preliminary analysis, use of the exoscope in fluorescence-guided surgery for high-grade gliomas provided significant advantages in terms of visualization of the surgical field under a blue filter and linearity of surgical flow.