Decrease In Intensity Research Articles

Effect of Different Light Intensities on the Quality of ‘Korla’ Fragrant Pear Fruits

This study aimed to investigate the effect of different light intensities on the quality of ‘Korla’ fragrant pear fruits. The differences in fruit quality were determined by evaluating the pigment content and fluorescent characteristics of the peel. The date of fruit weight, aspect ratio, soluble sugar content, soluble solid content, reducing sugar content, and vitamin C content of fruits, were higher under 100% light intensity than in shade treatment. However, firmness of the peel and pulp, and titratable acid content were enhanced in shade-treatment. Total chlorophyll, Chl a, and Chl b contents gradually decreased with the reduction in light intensity. The anthocyanin content gradually decreased with the decrease in light intensity. The maximum photochemical efficiency (FV/FM) of PSII significantly declined at 1% light intensity. As the light intensity decreased, the actual fluorescence quantum efficiency of PSII (F′V/F′M), non-photochemical quenching (NPQ), and actual photochemical efficiency of PSII (ΦPS II) progressively decreased. The results indicate that photoinhibition occurred in the peel of fragrant pear fruits. Shade treatment reduced the intrinsic quality of ‘Korla’ fragrant pear fruits, whereas a moderate decrease in light intensity could enhance the extrinsic quality of fruits.

Development of a universal plug tray seeder for small seeds based on electrostatic adsorption

Addressing the limitations of the traditional air suction plug tray seeder regarding versatility, clogging, noise, and energy consumption, a novel plug tray seeding method suitable for a broader range of small seed sizes has been proposed. A universal plug tray seeder has also been designed based on electrostatic adsorption for small seeds. Key factors affecting seed electrostatic adsorption were analyzed through electrostatic simulation, determining the optimal manufacturing method for the suction needle and the best range for the electrostatic voltage. Leveraging the theory of granular dynamics, a seed vibration box was designed using the principle of microphone vibration to enhance seed flowability and reduce the multiple seeding rate. Furthermore, the control system achieved seed recognition based on YOLOv8n and adaptive matching of seeding parameters, enhancing the universality of the seeder. The seeder was optimized and validated through practical experiments, with a comparative analysis of energy consumption and sound intensity conducted. The results indicated that the electrostatic suction needle, made with a single copper electrode of 1 mm diameter and coated with a 1 mm thick planar epoxy resin adsorption layer, along with an electrostatic voltage of 5 ∼ 10 kV, could effectively adsorb seeds. The vibration box significantly improved the seeding effect by vibrating seeds of tomato, pepper, and muskmelon at frequencies of 10 ∼ 25 Hz, and seeds of broccoli, cabbage, and eggplant at frequencies of 30 ∼ 50 Hz. The combined action of the electrostatic suction needle and the vibrating seed box resulted in an 83.20 % reduction in energy consumption and a significant decrease in sound intensity. Although the single seeding rate for muskmelon and cabbage seeds slightly decreased due to higher rates of leakage seeding and multiple seeding, the single seeding rate for other seeds remained around 90 %. This study provides a theoretical foundation for the universal seeding method of small seeds and offers significant reference value for the design of low-energy, low-noise plug tray seeders.

The effectiveness of giving young coconut water in reducing dysmenorrhea symptoms: A case study of midwifery care

Introduction: Dysmenorrhea is a common condition in women during menstruation, characterized by severe pain that can interfere with daily activities. The administration of medical therapy is often used to treat these symptoms, but natural approaches such as giving young coconut water are also starting to be considered. Objective: This study aims to analyze the effectiveness of giving young coconut water in reducing pain intensity in dysmenorrhea patients and provide an overview of the application of natural therapy-based obstetric care in patients with menstrual complaints. Methods: This study uses a case study design with a qualitative approach. The subject of the study was an adult woman who experienced primary dysmenorrhea. Data were collected through in-depth interviews, direct observation, and assessment of pain intensity using the VAS (Visual Analog Scale) scale before and after administering young coconut water. Result: The study showed a significant decrease in the intensity of dysmenorrhea pain after administering young coconut water. Before the administration of therapy, patients reported pain intensity at level 8 (scale 0-10), and after three days of administration of young coconut water, pain intensity decreased to level 3. Patients also reported feeling more comfortable and being able to continue their daily activities better. No significant side effects were found related to the consumption of young coconut water. I am injuring kei three mestiuia such does not feel jealous, the nature of the blood of meirah can bioactivity deingan good to know the absence of the current suidah in the absence of good. Conclusion: Giving young coconut water can be effective in reducing the symptoms of dysmenorrhea in patients who experience it. This therapy can be a safe and natural alternative to help relieve menstrual pain. It can be applied in obstetrics as part of a comprehensive approach to reproductive health care. Further research with larger samples is needed to reinforce these findings and explore the mechanism of action of young coconut water in dysmenorrhea

Comparison of responders and nonresponders with knee osteoarthritis after transcranial direct current stimulation.

The study compared responders and nonresponders to transcranial direct current stimulation (tDCS) regarding clinical pain outcomes in knee osteoarthritis (OA) patients. Sixty participants received home-based active tDCS, and clinical pain outcomes were compared between responders and nonresponders. Latent class growth analyses classified 41 participants as responders and 19 as nonresponders. Responders showed significantly greater decreases in pain intensity from baseline to post intervention than nonresponders (p < .001). Participants with higher BMI (p = .02) and weight (p = .005) were more likely to respond, while no significant sociodemographic differences were found. Identifying characteristics of nonresponsive tDCS subgroups can tailor treatments for each group. www.clinicaltrials.gov identifier is NCT04016272.

Water-Vapor-Triggered Dual-Mode Optical Responses in Rare-Earth-Doped Hollow Nanospheres.

Multimode responsive optical materials are garnering ever-increasing attention due to their diverse applications. This work showcases a film assembled with rare-earth-doped CaF2 hollow nanospheres that exhibit water-vapor-triggered dual-mode optical responses. Upon exposure to flowing water vapor, the film rapidly (less than 1.5 s for a 7.7 μm thickness) transitions to a transparent state and simultaneously undergoes a sharp decrease in the photoluminescence intensity. Both of these changes fully reverse upon water evaporation, demonstrating an impressive reversibility over at least 200 cycles. The water-vapor-induced dual-mode responses are attributed to the altered incident light propagation path stemming from the similar refractive indices between CaF2 and water, coupled with the water-induced energy loss of the rare-earth ions. The fabrication of encryption patterns displaying separate signals in multiple channels, as well as the demonstration of noncontact sensing for water vapor distribution, underscore the promising application potential of this dual-mode responsive system.

Intra-articular corticosteroid injections versus platelet-rich plasma as a treatment for cervical facetogenic pain: a randomized clinical trial

ObjectiveThe study’s primary objective was to compare the effectiveness of intra-articular platelet-rich plasma injections versus corticosteroid injections for the treatment of cervical facetogenic pain. Secondary aims were to compare self-rated...

Greater smoking intensity may be linked to early smoking initiation among Filipinos: Evidence from the 2021 Global Adult Tobacco Survey Philippines.

Understanding the relationship between age at smoking initiation and later smoking intensity is crucial for assessing future health consequences of smoking early and informing strategies to prevent and reduce tobacco use. This study explores the relationship between the two smoking-related behaviors among Filipino daily smokers. Secondary data analyses from the 2021 Global Adult Tobacco Survey Philippines were performed. This study covers those who were reported to be daily smokers. The outcome of interest was smoking intensity, measured as the number of manufactured cigarettes consumed per day, while the main predictor was age at smoking initiation. Data from 2260 participants were analyzed. Negative binomial regression was used to test for the relationship between age at smoking initiation and smoking intensity while controlling for sociodemographic variables and other smoking-related behaviors. The average age at which daily smoking commenced was 20.93 (SD=6.35) years, while the average number of manufactured cigarettes consumed per day was 9.50 (SD=7.26). Age at smoking initiation was a significant predictor of smoking intensity, even after controlling for potential confounders. Each additional year in the age at which smoking was initiated was associated with a 1.55% decrease in smoking intensity in the adjusted model (β= -0.0155, p<0.0001). Other predictors of smoking intensity were current age (β=0.0072; 95% CI: 0.0050-0.0094, p<0.0001), sex (β= -0.1146; 95% CI: -0.2157 - -0.0136, p=0.0262), and smoking rules at home (β=0.1807; 95% CI: 0.1175-0.2439, p<0.0001). Greater smoking intensity may be linked to early smoking initiation among Filipino adult daily smokers. The results may support interventions that target younger ages to curb heavy tobacco use at later ages.

Spectroscopic Measurements and Models of Energy Deposition in the Substrate of Quantum Circuits by Natural Ionizing Radiation

Naturally occurring background radiation is a potential source of correlated decoherence events in superconducting qubits that will challenge error-correction schemes. In order to characterize the radiation environment in an unshielded laboratory representative of superconducting qubits’ environments, we performed broadband, spectroscopic measurements of background radiation events inside a millikelvin refrigerator. The spectrometer was designed to mimic the size and composition of a quantum circuit. Specifically, we measured the background radiation spectra in silicon substrates of two thicknesses, 500 and 1500 µm, and one area, 25 mm2. The observed spectra span energies from a few kilo-electron-volts up to nearly 10 MeV, are nearly featureless, and decrease in intensity by a factor of 40 000 between 100 keV and 3 MeV for the 500-µm substrate. We integrate the spectra to obtain the average event rates and deposited power levels. These quantities correspond to a rate of 0.023 events per second and a power of 4.9 keV s−1, when counting events that deposit at least 40 keV for the 500-µm-thick substrate. We find that the cryogenic measurements are in good agreement with predictions based on simple measurements of the terrestrial gamma-ray flux outside the refrigerator, published models of cosmic-ray fluxes, a crude model of the cryostat, and radiation-transport simulations. This model requires no free parameters to predict the background radiation spectra in the silicon substrates. The agreement between measurements and predictions demonstrates that the model we present can be used to assess the relative contributions of terrestrial and cosmic-ray sources to background radiation interactions in silicon substrates of varying thickness. These spectroscopic measurements are performed with a novel combination of superconducting microresonators located on micromachined silicon islands that define the interaction volume with background radiation. The resonators transduce deposited energy to a readily detectable electrical signal. Microresonator readout closely resembles dispersive superconducting qubit readout, so similar devices—with or without micromachined islands—are suitable for integration with superconducting quantum circuits as detectors for background radiation events. For our specific laboratory conditions, we find that gamma-ray emissions from radioisotopes are responsible for the majority of events that deposit E&lt;1MeV. We present results demonstrating that the background radiation spectrum contains relevant contributions from cosmic-ray particles other than muons, particularly a tail of multi-mega-electron-volt events due to protons and neutrons. These observations suggest several paths to reducing the impact of background radiation on quantum circuits, supported by an empirically validated model for generating reliable predictions of radiation interactions with silicon substrates. Published by the American Physical Society 2024

Differences in species composition between calcareous and siliceous herbaceous communities are primarily explained by competition in favourable climates

Difference in vegetation composition between communities from calcareous and siliceous soils might be due to high competition on siliceous soils for species from calcareous origin, and high rock‐induced drought stress on calcareous soils for species from siliceous origin. We tested the hypothesis that, with increasing climate stress, competition should decrease on siliceous rock for species of calcareous origin and drought stress increase on calcareous rock for species of siliceous origin because of decreasing community biomass with increasing cold or drought stress. This question is of high interest for predicting changes in species distribution with climate change since bedrock type and climate change are both complex factors that are likely to interact with climate. We set up a transplant removal experiment in contrasting climate conditions of the south of France, warm and wet temperate, warm and dry Mediterranean, and cold temperate in the Alps and the Pyrenees. In each climate condition, three targets (two species and one population from a third species) from each origin were transplanted with and without neighbours on the two rock types and during two years with different levels of drought stress. Variation in the effects of neighbours and rock‐induced drought stress on transplant survival with and without neighbours were analysed with linear modelling at each site, separately, and with ANCOVA in the whole design. Competition was the highest on siliceous rock in the more favourable climate conditions but for species of siliceous origin. The lower competition found for species of calcareous origin was likely due to the occurrence of allelopathic effects that decreased the negative effect of neighbours as measured with the removal method. The rock‐induced drought stress was the highest on calcareous rock, in particular for species of siliceous origin. Thus, the decrease in competition intensity on siliceous rocks with increasing climate stress was more important for species from siliceous than calcareous origin. Additionally, the importance of the rock‐induced drought stress was relatively low in the most stressful climate conditions as compared to the overwhelming importance of climate drought stress over the two years of our experiment, which likely induced a collapse of the positive effect of growing on a siliceous rock.

Analysis of natural antibodies during the development of phantom pain syndrome

We determined natural antibodies (e-Abs) to the regulators of the main systems of biochemical homeostasis: β-endorphin, serotonin, dopamine, histamine, orphanin, angiotensin, GABA, glutamate, bradykinin, vasopressin, thrombin, α-2-macroglobulin in individuals with phantom pain syndrome (FBS), resulting from amputation after injury. It has been established that each patient has an individual immunoprofile, but for all of them there is a significant increase in the level of antibodies to serotonin, histamine and angiotensin, which reflect the chronicity of the pain syndrome and do not depend on the self-assessment of the severity of FBS. Determining the role of regulators of biochemical homeostasis in the development of phantom pain showed that with high, moderate and weak severity of FBS, the biogenic amine and angiotensinergic systems are activated. A decrease in FBS intensity normalizes deviations in all immunological parameters. The level of e-Abs for the pain (β-endorphin) and analgesic (orphanin) systems are significant only at low FBS. Monitoring the individual profile of e-Abs to endogenous regulators allows us to obtain an objective picture of the pain status of the patient’s body.

Mechano-responsive fluorescent gel based on tetraphenylethylene-crosslinked dynamic covalent network.

The rapid development of mechano-responsive fluorescence has been driven by its promising applications in the fields of sensors, information encryption, and anti-counterfeiting. However, designing mechanophores that can exhibit fluorescence changes under relatively low force remains challenging. In this study, a mechano-responsive fluorescent gel was developed using a tetraphenylethylene derivative as a cross-linker, producing a dynamic covalent network that exhibits increased fluorescence under tensile stress. Based on controlled experimental studies and molecular modeling calculations, the fluorescence enhancement by external forces was attributed to the restriction of intramolecular motion in tetraphenylethylene by macromolecular chain orientation. In time-dependent experiments, due to the exchange of dynamic covalent bonds, the stress relaxation and the decrease in fluorescence intensity of the gel at fixed strain occurred simultaneously, demonstrating the potential of this fluorescence as an indication of internal stress through aggregation-induced emission (AIE) type mechanophore.

Data-Driven Analysis of Ocean Fronts’ Impact on Acoustic Propagation: Process Understanding and Machine Learning Applications, Focusing on the Kuroshio Extension Front

Ocean fronts, widespread across the global ocean, cause abrupt shifts in physical properties such as temperature, salinity, and sound speed, significantly affecting underwater acoustic communication and detection. While past research has concentrated on qualitative analysis and small-scale research on ocean front sections, a comprehensive analysis of ocean fronts’ characteristics and their impact on underwater acoustics is lacking. This study employs high-resolution reanalysis data and in situ observations to accurately identify ocean fronts, sound speed structures, and acoustic propagation features from over six hundred thousand Kuroshio Extension Front (KEF) sections. Utilizing marine big data statistics and machine learning evaluation metrics such as out-of-bag (OOB) error and Shapley values, this study quantitatively assesses the variations in sound speed structures across the KEF and their effects on acoustic propagation shifts. This study’s key findings reveal that differences in sound speed structure are significantly correlated with KEF strength, with the channel axis depth and conjugate depth increasing with front strength, while the thermocline intensity and depth excess decrease. Acoustic propagation features in the KEF environment exhibit notable seasonal variations.

Identifikasi Perubahan Iklim dan Korelasinya terhadap Produksi Tanaman Padi (Oryza sativa L.) di Kabupaten Karawang

Rice is a food crop that is widely consumed by Indonesian people. Water availability and environmental conditions greatly influence the growth of rice plants, so that climate change can affect the production and productivity of rice plants. Efforts to anticipate a decline in rice production and productivity due to climate change require a study by identifying climate variabels, analyzing the correlation between climate and rice plants, and identifying solutions to adapt to climate change. The research was conducted in Karawang Regency using quantitative-descriptive methods, with the data analyzed being climate variabels including rainfall, temperature, humidity from 1991-2022 and rice plant variabels including rice production and productivity from 1991-2022. The analysis was carried out using trend analysis, correlation, regression, auto-regressive integrated moving average methods, and farmer interviews as analyses of adaptation strategies. The results of the research show that climate change has occurred in Karawang Regency as indicated by a decrease in rainfall intensity of 41.84 mm, a decrease in humidity percentage of 4.69%, and an increase in temperature of 〖0,92 〗^o C, and the climate type according to Oldeman is type D2, or there is no change in Oldeman’s Agroclimate zone. The results of interviews for adaptations include rotating crop planting, managing planting time, using seeds that are resistant to pest attacks, paying attention to the type of fertilizer used, controlling pests using insecticides or natural predators, and pumping water for irrigation channels.

Structure and functionality of Pleurotus geesteranus protein isolate as a function of pH.

Edible mushroom proteins hold great potential for food applications, but those extracted using the alkaline extraction-acid precipitation method typically exhibit poor solubility in neutral water, with the structural changes during acid precipitation remaining unclear. In this study, Pleurotus geesteranus protein isolate (PGPI) with high water solubility was prepared with alkaline extraction, followed by dialysis and freeze-drying, and the effects of pH on the structural and functional properties of PGPI were systematically investigated. PGPI was enriched in essential and aromatic amino acids, and the molecular weight of bands in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile was mainly distributed below 45kDa. The zeta potential of PGPI changed from +16.84 to 17.58mV when the pH increased from 2 to 9, with a pI of 4.3. At pH 7, PGPI showed a size of 232.7nm. Away from pH 7, the particle size of PGPI increased. When the pH decreased from 7 to 2, PGPI exhibited a lower α-helix structure content and a higher β-sheet content and a gradual decrease in fluorescence intensity. In addition, as the pH approached 4, H0 and the content of SS group increased to a peak. These results indicated that lowering the pH induced the development of more ordered protein structure, which could be the primary reason for the poor water solubility of P. geesteranus protein obtained through alkaline extraction and acid precipitation. Additionally, these structural changes result in alterations to its functional properties, including water-holding capacity, oil-holding capacity, foaming capacity, foaming stability, emulsion activity index, and emulsion stability index.

Tetraphenylethene-Containing Nanofilm via Interfacial Confinement Self-Assembly for Fluorescent Monitoring of SOCl2 Leakage in a Li-SOCl2 Battery Electrolyte.

Lithium thionyl chloride (Li-SOCl2) batteries are widely used due to their high energy density and long shelf life. However, the corrosive nature of SOCl2 poses a safety hazard, necessitating effective leak detection methods. We report an approach for real-time fluorescent detection of SOCl2 leakage in Li-SOCl2 batteries using a tetraphenylethene-based nanofilm. The nanofilms were prepared through the interfacial confined self-assembly method and exhibit excellent flexibility, homogeneity, tunable size and thickness, and adaptability to various substrates, enabling easy integration into sensor devices. They possess high photochemical stability and a photoluminescence quantum yield exceeding 25%, demonstrating their potential as high-performance fluorescent sensing material. The nanofilms also exhibit high sensitivity, good reproducibility, and selectivity toward SOCl2 detection. Upon exposure to SOCl2 vapor, the nanofilm shows a red-shifted and fluorescence quenching response, attributed to the protonation of the acylhydrazone bond in the nanofilm by the hydrolysis product of SOCl2, which disrupts the electronic structure of the nanofilm and leads to a decrease in the fluorescence intensity and a shift in the emission wavelength. A detection limit of ∼1.31 ppt and excellent repeatability over 300 cycles are demonstrated, highlighting their high sensitivity and reliability. This work paves the way for a highly sensitive and reliable leak detection system for Li-SOCl2 batteries, enhancing their safety and reliability in various applications.

Increases in Night Lights Intensity Reveal Extreme Events: A Case of Study on the Ongoing Conflict in Ukraine

Abstract. Analyzing night lights images allows identifying and monitoring affected areas during conflicts, as an overall decrease in brightness indicates abandoned or destroyed buildings, curfews, or power shortages. While detecting decrease in lights intensity is an established technique to identify critical areas during conflicts, the causes of appearing bright lights have not been extensively studied. An increase in brightness may be related to extreme events, such as fires resulting from bombing. This paper shows several examples supporting this new use of these images, validated using high-resolution optical earth observation data and ancillary information sources in the frame of the conflict in Ukraine which has been ongoing since February 2022.

Chlorophyll films for radiation dosimetry: a feasibility study

Abstract Novel Chlorophyll-PVA composite films have been prepared and tested for the dosimetry of therapeutic radiation. The radiation response has been quantified using UV–vis spectroscopy. FTIR and XRD spectroscopies have been used to characterize the physical properties and irradiation response of the films. The films have shown response towards the therapeutic x-rays beams of 6 MV nominal energy in the tested dose range of 0.25 Gy to 32 Gy in discrete dose levels occurring in the geometric progression series of 2. The dosimeter has been found to exhibit sensitivity at a low dose of 0.25 Gy. The dose response curve of the dosimeter exhibits an exponential relationship of the absorbance and absorbed dose. A region of saturated absorbance has been observed beyond 4 Gy. The peak intensities of the FTIR spectra have been found to decrease with increasing doses as compared to the unirradiated samples, because of the changes in the bond polarities and molecular geometries. The XRD spectra indicates a change in the molecular orientation resulting in a decrease in peak intensity with increasing dose. This study indicates the feasibility of chl-PVA films in the dosimetry of therapeutic radiation. This film dosimeter can be processed locally with minimum resources and standardized against a known standard before clinical use. The chlorophyll molecules need careful handling owing to their sensitivity to light and temperature.

Assessing plasmatic transport inhibitors of thyroid hormone in mammals in the Xenopus Eleutheroembryonic Thyroid Assay (XETA).

The Xenopus Eleutheroembryonic Thyroid Assay (XETA, OECD TG 248) was established as an alternative to the Amphibian Metamorphosis Assay (AMA, OECD TG 231) for the analysis of (anti-)thyroid activity of chemicals. The XETA is a New Approach Method (NAM) since the embryonic life stages used in the assay are not yet feeding independently, which renders the assay to be considered a non-animal test under many national laws. Physiologically, the used embryos are not fully developed yet, and thus there are limitations to the XETA for detecting certain mechanisms along the hypothalamic-pituitary-thyroid (HPT) axis. However, the plasmatic transport inhibition of thyroid hormone should physiologically be detectable in the XETA but has not yet been sufficiently investigated. Here, we tested three substances that are known, amongst others, to inhibit thyroid hormone transport by competitive binding to transthyretin in mammalian studies, namely pentachlorophenol (PCP), tetrabromo bisphenol A (TBBPA), and mefenamic acid. Following the test guideline, X. laevis eleutheroembryos of Nieuwkoop-Faber stage 45 were exposed for 72h at 21°C in 6-well plates to different concentrations of the test substances. For PCP and TBBPA, the XETA showed a decrease in fluorescence intensity, which would be expected for thyroid hormone transport inhibition amongst other, similar modes of action, while for the lower potency substance mefenamic acid, a trend was visible, but no statistically significant inhibition was detected. Overall, the results indicate that in the XETA, the plasmatic transport inhibition of thyroid hormone should be detectable alongside other inhibitory modes of action on the HPT axis.

The urban effects on the planetary boundary layer wind structures of typhoon Lekima (2019)

The urban effects on the planetary boundary layer (PBL) wind structures of landfalling tropical cyclones (TCs) have rarely been explored. In this study, numerical simulations for typhoon Lekima (2019), with and without multilayer building effect parameterization (BEP) and urban surfaces, were executed to investigate the urban effects on TC PBL wind structures. Validations against observations demonstrate that the simulation incorporating BEP and urban surface more accurately replicates the track, intensity and 10-m wind field of Lekima (2019). Based on the comparison between the simulations with and without urban surface, urban effects were analyzed, and the possible mechanisms were examined from the perspective of turbulent transport. Results show that urban surfaces have a deceleration effect on TC wind fields overall. This deceleration effect is most pronounced near the surface and decreases with height under 1 km above ground level. Urban surfaces reduce tangential winds and radial inflow in the near-surface layer, leading to a slight decrease in TC intensity. This is primarily attributed to the enhanced downward transfer of tangential momentum and upward transfer of radial momentum within the PBL, which results in larger magnitudes of negative tangential wind tendencies and positive radial wind tendencies induced by the divergence of subgrid-scale (SGS) momentum fluxes. Additionally, stronger tangential winds and radial outflow above the elevated PBL height correspond well to the increased tangential and radial wind tendencies in nearby areas. The analysis illustrates that turbulent transport provides insights into how urban surfaces affect the PBL wind structures of TCs.

Validated Spectrofluorometric Assay for Folic Acid Determination in Pure and Pharmaceutical Forms via Basic Fuchsin Fluorescence Quenching.

A simple, specific, sensitive, rapid, and cost-effective spectrofluorometric method for quantifying folic acid has been developed using basic fuchsin as a fluorescence quenching agent. This method relies on the quenching effect of folic acid on the inherent fluorescence of basic fuchsin, facilitated by their interaction in Britton-Robinson buffer solution at pH 9, leading to the formation of an ion-associated complex. The decrease in fluorescence intensity of basic fuchsin was measured at 730 nm, with excitation at 365 nm. The method demonstrated a linear relationship (R2 = 0.9977) between the quenching fluorescence intensity (ΔF) and folic acid concentration over the range of 4-20 μg/mL, with a detection limit of 0.17 μg/mL. The method showed no significant interference from common excipients found in pharmaceutical tablets. The results obtained were in good agreement with those from high-performance liquid chromatography, with no significant differences in precision or accuracy. This spectrofluorimetric method was successfully applied to determine the folic acid content in various commercial pharmaceutical tablets.