Duration Of Irradiation Research Articles

In silico ecotoxicity assessment of photoinduced imidacloprid degradation using HPLC–HRMS, QSAR and ecotoxicity equivalents

BackgroundImidacloprid is among the most widely used insecticides and today is found in surface and ground water worldwide. It has been registered in the EU watchlist for monitoring. To prevent imidacloprid from entering water bodies, advanced oxidation processes (AOP) have been intensely researched. Photo-irradiation proved one of the most efficient methods to degrade and eliminate anthropogenic micropollutants from waters. The ecotoxicity assessment of photoinduced degradation and transformation products especially in the absence of reference standards is still heavily explored.ResultsIn this study, UVA and UVC irradiation in combination with titanium dioxide P25 as photocatalyst were investigated for their degrading and eliminating effects and effectiveness on imidacloprid. Humic acid was used as natural organic matter additive. High-performance liquid chromatography coupled with high-resolution mass spectrometry allowed to identify and monitor imidacloprid and its degradation intermediates yielding seven new structures and concentration–time (c–t) profiles. The correlation of structures and the application of radical scavengers and photocatalyst helped distinguish between direct photoinduced and indirect hydroxyl radical-induced degradation mechanisms. The identification of hydroxylated products and intermediates indicated the indirect degradation pathway, which could be suppressed by addition of a radical scavenger. The absence of hydroxylated intermediates and fragments pointed towards the direct absorption-induced degradation. Two degradations products were traced back to the direct mechanism, whereas all other products followed the indirect mechanism. The ecotoxicity of the identified compounds was assessed by quantitative structure–activity relationship (QSAR) analysis. Most products were predicted as less ecotoxic. Ecotoxicity equivalents (ETEs) were introduced allowing a classified ranking of the products and an assessment of the overall hazardous potential of the irradiated solution at a given moment. Generally, the number of hydroxyl substituents was inversely correlated to ecotoxicity. From the c-t curves, time-dependent ETE profiles were established.ConclusionsStructure elucidation and c-t profiles from liquid chromatography–high-resolution mass spectrometry allowed to distinguish between direct and indirect degradation mechanisms. Structure specific ecotoxicity assessment could be achieved through QSAR analysis. Ecotoxicity hazard was ranked based on ETEs. The time-dependent ETE profile proved suitable to reflect the effect of irradiation duration and allow to estimate the irradiation time required to eliminate ecotoxicity, which may be relevant for potential applications in wastewater treatment plants.

Experimental study on ultrasonic irradiation for enhancing coalbed methane recovery

The present study proposes the use of a new ultrasonic irradiation method to enhance permeability and desorption for gas recovery from low-permeability coal reservoirs. A triaxial stress ultrasonic irradiation test apparatus was developed specifically for coal, considering the properties of gas adsorption, migration, and sound intensity, and providing a simultaneous measurement of gas flux, to investigated the deformation and temperature of coal samples obtained from the Fuxin coal field by permeability and desorption experiments. With the ultrasonic irradiation duration, the permeability of coal improved gradually with unequal variation, accompanied by the Klinkenberg effect where it decreased rapidly and then increased slowly with increasing gas pressure. The ability to desorb coal was enhanced by higher sound intensity ultrasound irradiation, and the volume of gas desorption was much greater than that of the sample without mange, the temperature and strain were demonstrated as a “J shaped” curve. An X-ray computer tomography (CT) technique was used to visualise the meso- or macro-cracks in the coal sample at pre- and post- ultrasonic irradiation, consequently, fractures expanded under the irradiation of ultrasonic waves. A permeability and desorption model was developed to describe the improvement of coal seam gas production capacity under ultrasonic irradiation, which introduced effective sound pressure.

Novel closed-cycle reaction mode for totally green production of Cu1.8Se nanoparticles based on laser-generated Se colloidal solution

Non-stoichiometric copper selenide (Cu2 – x Se, x = 0.18 ∼ 0.25) nanomaterials have attracted extensive attentions due to their excellent thermoelectric, optoelectronic and photocatalytic performances. However, efficient production of Cu2 – x Se nanoparticles (NPs) through a green and convenient way is still hindered by the inevitable non-environmentally friendly operations in common chemical synthesis. Herein, we initially reveal the coexistence of seleninic acid content and elemental selenium (Se) NPs in pulsed laser-generated Se colloidal solution. Consequently, we put forward firstly a closed-cycle reaction mode for totally green production of Cu1.8Se NPs to exclude traditional requirements of high temperature and toxic precursors by using Se colloidal solution. In such closed-cycle reaction, seleninic acid works as the initiator to oxidize copper sheet to release cuprous ions which can catalyze the disproportion of Se NPs to form and Se2– ions and further produce Cu2 – x Se NPs, and the by-product ions promote subsequent formation of cuprous from the excessive Cu sheet. In experiments, the adequate copper (Cu) sheet was simply dipped into such Se colloidal solution at 70 °C, and then the stream of Cu1.8Se NPs could be produced until the exhaustion of selenium source. The conversion rate of Se element reaches to more than 75% when the size of Se NPs in weakly acidic colloidal solution is limited between 1 nm and 50 nm. The laser irradiation duration shows negative correlation with the size of Se NPs and unobvious impact to the pH of the solution which both are essential to the high yield of Cu1.8Se NPs. Before Cu sheet is exhausted, Se colloidal solution can be successively added without influences to the product quality and the Se conversion rate. Such green methodology positively showcases a brand-new and potential strategy for mass production of Cu2 – x Se nanomaterials.

Self-regulated non-reciprocal motions in single-material microstructures.

Living cilia stir, sweep and steer via swirling strokes of complex bending and twisting, paired with distinct reverse arcs1,2. Efforts to mimic such dynamics synthetically rely on multimaterial designs but face limits to programming arbitrary motions or diverse behaviours in one structure3-8. Here we show how diverse, complex, non-reciprocal, stroke-like trajectories emerge in a single-material system through self-regulation. When a micropost composed of photoresponsive liquid crystal elastomer with mesogens aligned oblique to the structure axis is exposed to a static light source, dynamic dances evolve as light initiates a travelling order-to-disorder transition front, transiently turning the structure into a complex evolving bimorph that twists and bends via multilevel opto-chemo-mechanical feedback. As captured by our theoretical model, the travelling front continuously reorients the molecular, geometric and illumination axes relative to each other, yielding pathways composed from series of twisting, bending, photophobic and phototropic motions. Guided by the model, herewe choreograph a wide range of trajectories by tailoring parameters, including illumination angle, light intensity, molecular anisotropy, microstructure geometry, temperature and irradiation intervals and duration. We further show how this opto-chemo-mechanical self-regulation serves as a foundation for creating self-organizing deformation patterns in closely spaced microstructure arrays via light-mediated interpost communication, as well as complex motions of jointed microstructures, with broad implications for autonomous multimodal actuators in areas such as soft robotics7,9,10, biomedical devices11,12 and energy transduction materials13, and for fundamental understanding of self-regulated systems14,15.

Copper Ion and Ruthenium Complex Codoped Polydopamine Nanoparticles for Magnetic Resonance/Photoacoustic Tomography Imaging-Guided Photodynamic/Photothermal Dual-Mode Therapy.

Phototherapy, such as photodynamic therapy (PDT) and photothermal therapy (PTT), refers to the therapeutic strategy using a visible or near-infrared (NIR) laser to generate free radicals or heat for noninvasive and localized tumor treatment. However, limited by the low photoconversion efficiency of therapeutic agents, a single treatment method can hardly lead to complete tumor ablation, even when enhancing the power density of the laser and/or prolonging the irradiation duration. In this work, copper ion and ruthenium complex codoped polydopamine nanoparticles (Cu(II)/LRu/PDA NPs) are designed for PDT/PTT dual-mode therapy. The doped LRu in the NPs can generate reactive oxygen species under visible laser irradiation and enable PDT. Because of the strong absorption in the NIR region, PDA can not only generate heat for PTT under irradiation but also be used for photoacoustic tomography (PAT) imaging. Meanwhile, the doping of Cu(II) in the NPs through the coordination with PDA facilitates T1-weighted magnetic resonance imaging (MRI). Thus, MR/PAT imaging-guided PDT/PTT dual-mode therapy is achieved. The in vivo experiments indicate that the Cu(II)/LRu/PDA NPs can accumulate in HeLa tumors with a retention rate up to 8.34%ID/g. MR/PAT imaging can clearly identify the location and boundary of the tumors, permitting precise guidance for phototherapy. Under the combined effect of PDT and PTT, a complete ablation of HeLa tumors is achieved. The current work provides an alternative nanoplatform for performing PDT/PTT dual-mode therapy, which can be further guided by MR/PAT imaging.

Phototherapy Using Er,Cr:YSGG Laser as a Definitive Treatment for Dentin Hypersensitivity: A Systematic Review

PurposeTo assess the efficacy of Er,Cr:YSGG lasers in reducing dentine hypersensitivity (DH).MethodsElectronic literature were searched through various databases (MEDLINE, SCOPUS, ProQuest, LILACS and EBSCO) up to March 2022 for articles addressing the following focused question: “In patients with dentine hypersensitivity, does an Er,Cr:YSGG laser provide a better outcome in terms of pain reduction than other dentine desensitizer agents?”. The literature was searched using combinations of the following medical subject heading (MeSH) terms and keywords: (laser OR phototherapy OR Er,Cr:YSGG laser) AND (dentine hypersensitivity OR dentine sensitivity OR dental sensitivity).ResultsA total of 486 studies were found, of which 7 randomized controlled trials were included in the review. The Er,Cr:YSGG laser wavelengths, power density and duration of irradiation used in the studies were 2780 nanometers, 0.25–0.5 watts and 20–60 seconds, respectively. The follow-up assessments were conducted ranging from immediately to 3 months after treatment. All studies showed that the Er,Cr:YSGG laser was effective in alleviating DH.ConclusionThis systematic review suggests that the application of an Er,Cr:YSSG laser is effective in alleviating DH and may have limited adverse effects if adequate parameters are followed.

Association of Photodynamic Therapy and Photobiomodulation As a Promising Treatment of Herpes Labialis: A Systematic Review.

Background: This systematic review aims to analyze the effectiveness of the association of photodynamic therapy (PDT) and photobiomodulation (PBM) in the treatment of recurrent herpes labialis and to analyze the very many variables of parameters applied, number of sessions, photosensitizer concentration, and the timing of the intervention to offer clinicians an indication of the most likely optimal techniques and parameters required to achieve clinical success. Methods: This study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA Checklist and registered at the International Prospective Register of Systematic Reviews (PROSPERO). We searched and identified articles of the subsequent bibliographic databases: PubMed and Cochrane. Results: Since there are no clinical trials regarding the association of PDT and PBM in the treatment of herpes labialis, we only included case reports in our review. All studies used methylene blue solution as the photosensitizer and the laser (diode laser or low-power laser) with a wavelength of 660 nm as the light source. Power output, power density, number of irradiation points, number of PBM sessions, and irradiation duration varied between the included studies. Despite the diversity in parameters between studies, all case reports showed good results regarding relieving symptoms, accelerating healing, as well as reducing the incidence of recurrence without side effects. Conclusions: The association of PDT in the vesicular phase and PBM in the crust phase can be considered a promising solution for recurrent labial herpes. Despite the many successful cases reported, establishing an effective clinical protocol for the treatment of herpes labialis using PDT followed by PBM will only be possible through double-blind placebo studies that would elucidate the exact action of this treatment modality, the appropriate irradiation parameters for both therapies, optimal timing, and number of PBM sessions following PDT. This review has been registered at the International Prospective Register of Systematic Reviews (PROSPERO) under number CRD42021290757.

Combined accelerated collagen crosslinking and sub-Bowman’s keratomileusis in high myopic eyes: a comparison between total ultraviolet energy dose

ABSTRACT Aim To compare the safety, efficacy, and predictability outcomes of combined sub-Bowman’s keratomileusis (thin flap laser in situ keratomileusis [LASIK]) and accelerated crosslinking (CXL) using two different irradiation durations. Methods A retrospective comparative study of patients with percent tissue altered ≥35%, undergoing simultaneous CXL during sub-Bowman’s keratomileusis were recruited. Following riboflavin application, they underwent ultraviolet-A (UVA) irradiation (18 mW/cm2) for either 2 min (total energy 2.16 J/cm2) or 3 min (total energy 3.24 J/cm2). Visual and refractive outcomes were compared between follow-up visits during the first year postoperatively. Demarcation line and endothelial cell count were evaluated, respectively, at 1 and 3 months postoperatively. Results The baseline characteristics were similar between the 40 eyes/patients treated using the 2-min protocol and the 33 eyes/patients treated with the 3-min protocol (p ≥ .114). Uncorrected distance visual acuity and corrected distance visual acuity were significantly better for eyes treated with the shorter irradiation protocol on Day 1 (p ≤ .030) and Month 1 (p ≤ .040) postoperatively; these differences diminished by Month 3 (p ≥ .070). Likewise, the efficacy index was higher during the first postoperative week for the 2-min protocol (p ≤ .043). At 1 year, the proportion of eye attaining within 0.5 D of target refraction was 80.0% and 84.8% for the 2-min and 3-min protocols, respectively (p = .590). The corresponding corneal stromal demarcation line depth and endothelial cell density changes were comparable between the two groups (p = .311 and 0.899, respectively). Conclusions A comparable volume of crosslinked corneal tissue can be achieved by using a shorter UVA irradiation duration. Additional duration of UVA irradiation could lead to delay in visual rehabilitation after simultaneous sub-Bowman’s keratomileusis and CXL.

Optimization of endocrine pancreas fluorescence analysis using machine methods

The study aims to establish the appropriate parameters of UV excitation intensity and permanent excitation time on the pancreatic islets photobleaching, the ratio of the intensity of the useful signal in the region of interest to the intensity of nonspecific background fluorescence. Materials and methods. The pancreas of three adult Wistar rats was fixed in Bouin solution (20 hours) and poured into paraplast after standard histological processing. The study was carried out on paraffin sections of the pancreas. The islets’ insulin and glucagon were determined by immunofluorescence method using monoclonal antibodies (Santa Cruz Biotechnology). The immunofluorescence reaction was studied using an AxioImager-M2 fluorescent microscope. AxioVision digital image analysis system was used for fluorescence imaging, and ImageJ 64-bit image analysis system was used for image quantification. 30 pancreatic islets with an area from 3000 µm2 to 5000 µm2 (8–13 % of the frame area) were analyzed. Results. Measurements carried out at constant values of hormone concentration in endocrinocytes showed a different estimate of the average fluorescence intensity for insulin and glucagon, which depended on the intensity of UV radiation. As the intensity of UV radiation increased, the average fluorescence intensity in the region of interest for insulin and glucagon increased, but when the camera exposure was corrected, it became almost the same. Regardless of this, the intensity of nonspecific background fluorescence increased monotonically. The use of the ratio of the logarithms of the background fluorescence of the drug and the fluorescence of endocrinocytes in the calculations gives a stable estimate of the relative concentration of hormones, which does not depend on the intensity of the selected UV radiation regime, as well as on the duration of UV irradiation of the drug. This makes it possible to neutralize the effect of photodynamic discoloration of the preparation caused by continuous irradiation. Methods for machine selection of the region of interest by various algorithms of the ImageJ program lead to different estimates of its area, integral, and average fluorescence values. At the same time, the result closest to the “ideal” interactive method of highlighting the area of interest for insulin and glucagon was shown by Otsu’s algorithm. Conclusions. In immunofluorescent examination of the pancreas, a moderate UV radiation mode should be selected, exposure correction of the CCD camera before taking each frame, and the total time for examining the visual field of the sample should be limited to 1–2 minutes. To highlight the area of interest for insulin and glucagon in automatic analysis, it is recommended to use the Otsu algorithm. To obtain a quantitative estimate of the average fluorescence intensity in the region of interest, it is recommended to use the ratio of the logarithms of the background fluorescence of the drug and endocrinocytes in the calculations.

Photocatalytic-triggered nanopores across multilayer graphene for high-permeation membranes

2D nanoporous graphene nanomaterials have been considered for the development of high permeability membranes, compared to dense laminate architectures. Current perforation technologies, however, have struggled to deliver a membrane for practical use due to a lack of scalability and increased related complexity/costs over commercial membranes. Herein, the perforation of ultrathin graphene membranes, with thicknesses ranging from 50 to 200 nm were performed via a triggered and site-selective photocatalytic etching process. The perforated graphene membranes exhibited a narrow distribution of in-plane nanopores with sizes ranging from 20 and up to100 nm, depending on irradiation durations. The surface pore density across porous graphene can be tuned, achieving a maximum surface density of 1011 cm−2, depending on the amounts of pore-mediators i.e. nano-catalysts loaded to multilayer graphitic assemblies. The perforated membranes exhibited a water permeation of 85 LMH/bar, 3.5 times higher compared to unperforated membrane analogues though a decrease in dye removal (∼20% for the methylene blue organic dye) was noted over the extended permeation duration (2-hour). The synergetic characteristics between inherent nanochannels between graphite planes and incorporated nanopores across such ultrathin perforated graphene membranes promise improvements in water treatment using such architectures of high permeability graphene membranes.

Inactivation of Bacillus subtilis by Curcumin-Mediated Photodynamic Technology through Inducing Oxidative Stress Response.

Photodynamic sterilization technology (PDT) is widely used in disease therapy, but its application in the food industry is still at the research stage because of the limitations of food-grade photosensitizers. Curcumin exhibits photosensitivity and is widely used as a food additive for its natural color. This study aimed to determine the effect of curcumin-mediated photodynamic technology (Cur-PDT) on Bacillus subtilis and to elucidate the anti-bacterial mechanism involved. First, the effects of curcumin concentration, duration of light irradiation, light intensity, and incubation time on the inactivation of B. subtilis were analyzed. It was found that Cur-PDT inactivated 100% planktonic cells with 50 μmol/L curcumin in 15 min (120 W). Then, the cell morphology, oxidation state and the expression of membrane structure- and DNA damage-related genes of B. subtilis vegetative cells were investigated under different treatment conditions. The membrane permeability of cells was enhanced and the cell membrane structure was damaged upon treatment with Cur-PDT, which were exacerbated with increases of treatment time and curcumin concentration. Meanwhile, the production of reactive oxygen species increased and the activities of the antioxidant enzymes SOD, GPX, and CAT decreased inside the cells. Furthermore, the Cur-PDT treatment significantly downregulated the mRNA of the membrane protein TasA and upregulated the DNA damage recognition protein UvrA and repair protein RecA of B. subtilis. These results suggested that curcumin-mediated PDT could effectively inactivate B. subtilis by inducing cell redox state imbalance, damaging DNA, and disrupting membrane structures.

Thermal Effects of CO2, KTP, and Blue Lasers with a Flexible Fiber Delivery System on Vocal Folds

To determine the differences in thermal effects on vocal folds between four fiber-routed lasers. In this experimental laboratory study the thermal effects of an AcuPulse Duo CO2 (CO2 AP), UltraPulse Duo CO2 (CO2 UP), KTP, and Blue laser were analyzed using a Schlieren technique on a human tissue mimicking gel model. Power, laser duration, laser fiber distance to tissue and mode (continuous wave [CW] vs pulsed [P] modes) were evaluated in varying combinations in order to compare the effects of the tested lasers and to explore the individual effect on thermal expansion and incision depth of each setting. The model was validated by comparing the results from the Schlieren model with histology of ex vivo fresh human vocal folds after laser irradiation using a selection of the same laser settings, and calculating the intraclass correlation coefficient (ICC). One thousand ninety-eight Schlieren experiments and 56 vocal cord experiments were conducted. In comparison with CW mode, less thermal expansion occurred in P mode in all lasers, while incisions were deeper in the CO2 and more superficial in the KTP and Blue lasers. The mean thermal expansion was found to be minimally smaller, whereas incision depth was pronouncedly smaller in the KTP and Blue compared to the CO2 lasers. Duration of laser irradiation was the most important factor of influence on thermal expansion and incision depth for all lasers in both CW and P modes. The ICC for consistency between the results of the Schlieren model and the vocal cord histology was classified from fair to excellent, except for the thermal expansion of the Blue laser, which was classified as poor. This study demonstrates important differences in thermal effects between CO2, KTP, and Blue lasers which can be explained by the different physical characteristics of the P modes and divergence of the fiber delivery system. The Schlieren imaging model is a good predictor of the relative thermal effects in vocal fold tissue. Our results can be used as a guidance for ENT surgeons using fiber-routed lasers, in order to achieve effective treatment of vocal fold lesions and prevention of functional impairment of vocal folds.

Redispersed Bi nanoparticles on graphene fiber fabric anode regulated by microwave irradiation for flexible sodium ion capacitors

• Flexible electrode of Bi nanoparticles anchored on graphene fiber fabric is fabricated. • Micro-sized Bi can be redispersed into 20 nm on GFF in 5 s by microwave. • Competitive mechanisms are proposed to dominate the redispersion. • Flexible Bi/GFF anode exhibits superior Na + storage capacity for sodium ion capacitors. Sp 2 dominated carbon supported metal nanoparticles with well-controlled structures are promising for portable electrochemical energy storage device with “triple-high” (energy, power, and cycle) feature, yet remains elusive. We report here a flexible graphene fiber fabric (GFF) with well-dispersed Bi nanoparticles by a facile and efficient microwave (MW) irradiation method. By regulating the irradiation duration and π-π conjugated structure of GFF, the pristine micro-sized Bi particles can be uniformly redispersed on GFF with an average particle size of 20 nm in 5 s. The competitive mechanisms between the MW accumulated energy and surface energy of Bi nanoparticles as well as energy conversion efficiency are proposed to dominate this redispersion and particle size changing process. The entire Bi/GFF composite exhibits good conductivity, flexibility, and superior sodium ion storage specific capacity of 113 mAh g −1 at 30 A g −1 , which are conceptionally demonstrated as an anode for flexible sodium ion capacitors (SICs). The quasi-solid-state SICs exhibit great mechanical-electrochemical stability, integration property, long-term stability, and high energy/power densities. This work offers a model material of sp 2 dominated carbon supported metal nanoparticles with well-controlled structures by an efficient and facile route, demonstrating a potential for flexible, and “triple-high” energy storage device in the future.

Rainfall Prediction in Blora Regency Using Mamdani's Fuzzy Inference System

In the case study of weather prediction, there are several tests that have been carried out by several figures using the fuzzy method, such as the Tsukamoto fuzzy, Adaptive Neuro Fuzzy Inference System (ANFIS), Time Series, and Sugeno. And each method has its own advantages and disadvantages. For example, the Tsukamoto fuzzy has a weakness, this method does not follow the rules strictly, the composition of the rules where the output is always crisp even though the input is fuzzy, ANFIS has the disadvantage of requiring a large amount of data. which is used as a reference for calculating data patterns and the number of intervals when calculating data patterns and Sugeno has the disadvantage of having less stable accuracy results even though some tests have been able to get fairly accurate results. In research on the implementation of the Mamdani fuzzy inference system method using the climatological dataset of Blora Regency to predict rainfall, it can be concluded as follows: (1) The fuzzy logic of the Mamdani method can be used to predict the level of rainfall in the city of Blora by taking into account the factors that affect the weather, including temperature, wind speed, humidity, duration of irradiation and rainfall. (2) Fuzzy logic for prediction with uncertain input values is able to produce crisp output because fuzzy logic has tolerance for inaccurate data. (3) The results of the accuracy of calculations using the Mamdani fuzzy inference system method to predict rainfall in Blora Regency are 66%.

Optimization of the Duration and Intensity of UV-A Radiation to Obtain the Highest Free Phenol Content and Antioxidant Activity in Sprouted Sorghum (Sorghum bicolor L. Moench).

Technologies such as UV-A radiation applied to sprouted sorghum can stimulate the synthesis or release of phenolic compounds. Since the optimal conditions for stimulating the formation of these compounds in sorghum sprouts are unknown, we used the response surface methodology to identify the optimal conditions of irradiation duration and intensity to obtain the highest free phenol content and antioxidant activity in sprouted sorghum. The results showed that, compared with nonirradiated sorghum sprouts, sprouts irradiated under the optimal duration of 11.7h and the optimal intensity of 5.4µW/cm2 had a significantly higher phenol content (26.3%) and antioxidant activity as measured by DPPH (28.3%) and TEAC (21.1%) assays. Our findings suggest that UV-A radiation can help develop sorghum sprouts with high biological potential that can be used to produce healthy foods for human consumption.

Depth-targeted intracortical microstroke by two-photon photothrombosis in rodent brain.

.Significance: Photothrombosis is a widely used model of ischemic stroke in rodent experiments. In the photothrombosis model, the photosensitizer rose bengal (RB) is systemically introduced into the blood stream and activated by green light to induce aggregation of platelets that eventually cause vessel occlusion. Since the activation of RB is a one-photon phenomenon and the molecules in the illuminated area (light path) are subject to excitation, targeting of thrombosis is unspecific, especially in the depth dimension. We developed a photothrombosis protocol that can target a single vessel in the cortical parenchyma by two-photon excitation.Aim: We aim to induce a thrombotic stroke in the cortical parenchyma by two-photon activation of RB to confine photothrombosis within a vessel of a target depth.Approach: FITC-dextran is injected into the blood stream to visualize the cerebral blood flow in anesthetized adult mice with a cranial window. After a target vessel is chosen by two-photon imaging (950 nm), RB is injected into the blood stream. The scanning wavelength is changed to 720 nm, and photothrombosis is induced by scanning the target vessel.Results: Two-photon depth-targeted single-vessel photothrombosis was achieved with a success rate of and an irradiation duration of . Attempts without RB (i.e., only with FITC) did not result in photothrombosis at the excitation wavelength of 720 nm.Conclusions: We described a protocol that achieves depth-targeted single-vessel photothrombosis by two-photon excitation. Simultaneous imaging of blood flow in the targeted vessel using FITC dextran enabled the confirmation of vessel occlusion and prevention of excess irradiation that possibly induces unintended photodamage.

Tuning the structure, optical, and magnetic properties of nanostructured NiMoO4 by nitrogen plasma treatment

Herein, the nitrogen plasma treatment with different time irradiation (0, 90, 120, and 150 min) is used to tune the structure, optical, and magnetic properties of nanostructured NiMoO4 NMO NPs. The XRD patterns revealed that the crystallinity of NMO samples increases with an increase in the N2 plasma exposure time. The notable reduce in this peak’ intensity for the sample at dose of 120 min may be attributed to the energy dissipated in the defect generation. Also, the crystallite size for NMO samples was found in the range (23.9–26.7) nm. Further, EPR is used to evaluate the impact of the treatment duration on the oxygen vacancy density. The total number of spins rises as plasma irradiation duration increases, revealing that the NMO NPs can be used as a dosimeter for plasma irradiation. The optical bandgap ranged from 2.92 eV to 3.24 eV as the N2 plasma treatment duration changed. The saturation magnetization was enhanced with the rise of plasma treatment time. Furthermore, the Hc increases from 16.67 G for untreated NMO NPs to 128.41 G for N2 plasma-treated NMO NPs for 150 min. The resulted optical and magnetic properties of N2 plasma-treated NMO NPs make it candidate material for photocatalysis applications.

Combination of Vortex Agitation and Ultrasonic Irradiation for Mercury Removal from Sediment by Acid Extraction.

The removal of Hg from solid waste plays a key role in environmental protection. In this study, a fast, simple, and effective method for the removal of Hg by acid extraction, using a combination of vortex agitation and ultrasonic irradiation along with hydrobromic acid (HBr), was established using Hg-containing solid wastes. The optimal durations of vortex agitation and ultrasonic irradiation with 48% v/v of HBr were 5 and 6min, respectively, and total Hg (T-Hg) extraction was achieved within 21min. The proposed method was validated using the Certified Reference Material (CRM) ERM CC580 (estuarine sediment) and CRM NMIJ 7302-a (marine sediment). Under the optimized conditions, the efficiency rates of T-Hg extraction in both CRMs were 99.5% and 94.2%, with repeatabilities of 3.21% RSD and 2.31% RSD, respectively. The proposed extraction method can also be used for the remediation of Hg in other environmental matrices.

Singlet oxygen generation in aerosol jet and on biological surfaces.

The paper presents steady-state and time-resolved experiments on photophysical processes associated with photodynamic inactivation of infections provided by nebulization of Radachlorin photosensitizer solution. As models of surfaces subjected to photodynamic inactivation we used glass, plant leaf, mushroom cap peel and superficial fascia of chicken and salmon skin flaps. The oxygen content in the photosensitizer solution was varied by blowing with atmospheric air and with pure oxygen. It was shown that singlet oxygen was generated efficiently in the aerosol jet and that its amount increased noticeably at higher oxygen concentrations. The kinetics of photosensitizer photobleaching on different surfaces were found to be significantly different with characteristic decay times varying from seconds for leaf and glass to minutes for fascial flaps. This observation was attributed to much faster oxygen depletion on rough crumbly surfaces of biological samples due to effective oxidation reactions occurred. The singlet oxygen generation and degradation times, and the relative quantum yield were determined on different surfaces by recording time-resolved phosphorescence at about 1270nm under normoxic and hyperoxic conditions and analyzed on the basis of the set of master equations. The results obtained provide reference marks for choosing optimal irradiation durations for photodynamic inactivation of pathogenic infectious agents (bacteria, mycobacteria, fungi, viruses) on mucous membranes, including the tracheobronchial tree.

Nuclear Sample Provenance and Age Determination Using Ruthenium Isotopes.

Measurements of the ruthenium isotopic composition of nuclear samples could provide information about the method of sample production, sample irradiation history, and age. To investigate the feasibility and applicability of this idea, this study focuses on measurements of the ruthenium isotope composition of a nominally single-isotope 106Ru radioactivity standard, where the complications of environmental mixing are eliminated. The measurements of the 106Ru standards reveal unusual stable ruthenium isotopic compositions consistent with fissiogenic ruthenium. Three different lots of the material have been investigated, and the isotopic composition is found to be different for lot 1 as compared to lots 2 and 3, indicating a longer irradiation duration incurred during the production of lot 1. Through measurements of 106Ru and its 106Pd daughter, radiochronometry can be used to infer the ages of the samples. Lot 1 is older than lots 2 and 3 and was produced 4.91(5) years before the reference date of 1/1/21, approximately 2.7 years before lots 2 and 3. In an effort to better understand the sample production pathway, the isotopic measurements are compared with nuclear reactor simulations, which suggest that the material was generated by irradiation of a low-enriched uranium target material in a light water reactor. These findings have significant implications for nuclear treaty monitoring, providing an example of the power of ruthenium isotope measurements to discern details of sample origin and history.