Absorption Changes Research Articles

Acid content sensitive colorimetry of poly-N-phenyl-o-phenylenediamine for state of charge determination of lead-acid battery

The ex-situ colorimetric method of battery acid estimation was developed using poly-N-phenyl-o-phenylenediamine (PPOPD) to accurately determine the lead acid battery's state of charge (SoC). PPOPD was synthesized by the in-situ oxidative chemical polymerization of N-phenyl-o-phenylenediamine monomer (POPD) using ferric chloride as an oxidizing agent in ethanol solvent. The UV–visible absorption peak of PPOPD in acidic solutions at 518 nm showed a sharp positive linear slope with increased acid content. The charging or discharging mechanism of the battery produces changes in battery acid content. A fully charged lead-acid battery contains approximately 39.7 % sulphuric acid, whereas its acid content decreases by approximately 10 % on discharge. The PPOPD polymer showed a change in absorbance with a change in the lead-acid battery's acid percentage, which can be correlated with the state of charge. The absorbance of PPOPD solution was calibrated linearly with the sulphuric acid percentage (6–40 %), a similar acid range produced inside the battery during charging or discharging. The absorbance of PPOPD solution obtained in 10 % and 40 % sulphuric acid at 518 nm was set as the lower and upper limits (Amin and Amax) respectively for SoC determination. Therefore, the state of charge in any lead-acid battery under investigation can be determined by measuring the absorbance of the PPOPD solution. The state of charge obtained from the colorimetric method was compared with an open circuit voltage method using a 12 V lead-acid battery.

Observed Energetic Adjustment of the Arctic and Antarctic in a Warming World

Abstract Satellite observations reveal that decreasing surface albedo in both polar regions is increasing the absorption of solar radiation, but the disposition of this absorbed energy is fundamentally different. Fluxes of absorbed solar radiation, emitted thermal radiation, and net energy imbalances are assessed for both polar regions for the last 21 years in the Clouds and Earth’s Radiant Energy System record. Arctic absorbed solar radiation is increasing at 0.98 ± 0.69 W m−2 decade−1, consistent with the anticipated response to sea ice loss. However, Arctic thermal emission is responding at a similar rate of 0.94 ± 0.55 W m−2 decade−1. This is surprising since the radiative impact of ice loss would be expected to favor increasing solar absorption. We find however, that clouds substantially mask trends in Arctic solar absorption relative to clear sky while having only a modest impact on thermal emission trends. As a result, the Arctic net radiation imbalance has not changed over the period. Furthermore, variability of absorbed solar radiation explains two-thirds of the variability in annual thermal emission suggesting that Arctic thermal fluxes rapidly adjust to offset changes in solar absorption and re-establish equilibrium. Conversely, Antarctic thermal emission is not responding to the increasing (although not yet statistically significant) solar absorption of 0.59 ± 0.64 W m−2 decade−1 with less than a third of the annual thermal variability explained by accumulated solar absorption. The Arctic is undergoing rapid adjustment to increasing solar absorption resulting in no change to the net energy deficit, while increasing Antarctic solar absorption represents additional energy input into the Earth system. Significance Statement The polar regions of Earth are undergoing ice loss through ongoing global warming, reducing the ice cover and decreasing solar reflectivity, which would be expected to warm these regions. We use satellite observations to measure the trends in solar absorption and emitted thermal radiation over the Arctic and Antarctic for the last two decades. Arctic thermal emission is increasing at a compensating rate to solar absorption with a close relationship between these processes. Conversely, Antarctic thermal emission is not responding to solar absorption demonstrating that Antarctic surface temperatures are not significantly influenced by the region’s reflectivity. The Arctic is undergoing rapid adjustment to increasing solar absorption through warming, while increasing Antarctic solar absorption represents additional energy input into the Earth system.

Selective and Effective Sensing of Cyanide Ion with no Interference in Water by Phenothiazine-indolium Fused Optical Sensor.

The sensor with electron donor phenothiazine-2-carbaldehyde and electron acceptor indolium carboxylic acid, is developed with an intramolecular charge transfer transition between them. The synthesized molecule senses cyanide ion in water. The cyanide ion reacts with the molecule via nucleophilic addition in the indolium ring with a noticeable purple to colorless change in the solution observed. Also with the cyanide ion interaction, the sensor exhibits change in UV-visible absorption and fluorescence spectra. While the other ion does not show spectral and visual changes when interacts with the sensor molecule. Also the interference study reveals that the molecule is highly selective towards cyanide ion. Different source of water samples confirms the CN- ion sensing efficiency of the molecule. 1:1 interaction between the molecule PTI and cyanide ion is confirmed from the results of Jobs plot, 1H NMR and HRMS. Paper strips were prepared and this can act as a simple tool to sense cyanide ion in various water samples.

RENAL DYSFUNCTION IN PRETERM INFANTS WITH PERINATAL PATHOLOGY: RISK FACTORS, SENSITIVITY AND SPECIFICITY OF LABORATORY MARKERS OF DAMAGE

The main burden of neonatal morbidity in critically ill preterm infants, despite signifi cant achievements and rapid development of care technologies, is most often associated with neonatal sepsis, perinatal asphyxia and the development of multiple organ failure syndrome. As a component of this syndrome, newborns with combined perinatal pathology in the early neonatal period manifest severe renal dysfunction up to acute kidney injury, which is closely correlated with increased mortality. The incidence of acute kidney injury in critically ill preterm infants varies widely, ranging from 25 to 77 % according to diff erent neonatal data. A major problem in the fi eld of neonatal nephrology is the lack of uniform approaches for the diagnosis of moderate and severe renal dysfunction at the subclinical stage, which would allow the timely formation of risk groups and the optimization of interventional strategies.Aim of the study. To analyze the data on clinical characteristics, risk factors, and results of additional paraclinicalexaminations in preterm infants with gestational age of 34-36/6 weeks who had severe and moderate perinatal pathology during the early neonatal period.Material and methods. A comprehensive study of 91 premature infants with moderate and severe perinatal pathology wasconducted, of which group I consisted of 30 children with severe perinatal pathology at 34-36/6 weeks’ gestation, group II – 30 children with moderate perinatal pathology at 34-36/6 weeks’ gestation; group III (control) consisted of 31 conditionally healthy premature infants at 34-36/6 weeks’ gestation.The diagnosis of acute kidney injury in neonates in the comparison groups was made according to the International Criteriafor Kidney Disease: Improving Global Outcomes as modifi ed by J. G. Jetton and D. J. Askenazi (2015). The international scaleNeonatal Multiple Organ Dysfunction Score was used to assess the severity of multiorgan dysfunction in perinatal pathology.The eff ectiveness of therapeutic interventions was assessed using the international scale Neonatal Therapeutic Intervention Scoring Scale, and the severity of the patient’s condition in dynamics was assessed using the neonatal scale Score for Neonatal Acute Physiology.Methods of laboratory research. The study of the biochemical spectrum of urine in children of the observation groups,in particular, the determination of the level of markers of kidney damage – alpha-1-microglobulin, beta-2-microglobulin,microalbumin, cystatin C was carried out on the basis of the problematic research laboratory of the Bukovinian State Medical University of the Ministry of Health of Ukraine using the automatic analyzer «ACCENT-200» and «ACCENT-200 II CEN». Urine was collected on the 3rd day of life (between 48-72 hours of life), in sterile disposable containers, in the amount of at least 5 ml.At the same time, a blood sample for cystatin C determination was taken in the amount of 0.5-1.0 ml, in accordance with the rules of asepsis and antisepsis in disposable sterile tubes. A turbodimensional immunoassay was used to determine the concentration of cystatin C and urinary microalbumin. Determination of alpha-1-microglobulin was performed using an ACCENT-200 automated analyzer by measuring agglutination by change in absorbance (572 nm), with actual concentration determined by interpolation from a calibration curve constructed using calibrators of known concentration. The concentration of beta-2-microglobulin in urine was determined by the method of competitive chemiluminescence analysis.The studies were conducted in accordance with the basic provisions of GCP (1996), the Convention of the Council of Europeon Human Rights and Biomedicine (April 4, 1997), the World Medical Association Declaration of Helsinki on Ethical Principlesfor Research Involving Human Subjects (1964-2008), Order of the Ministry of Health of Ukraine No. 690 of September 23, 2009 (as amended by Order of the Ministry of Health of Ukraine No. 523 of July 12, 2012).Statistical analysis of the results was performed using Statistica 10 software (StatSoft Inc., USA, 2010), MedCalc software(version 16.1) with calculation of chi-squared, odds ratio (OR), 95 % confi dence interval (CI), statistically signifi cant diff erences between the study groups were considered at a value of p<0.005. Receiver operating characteristic (ROC) curves, area under ROC (AUROC), sensitivity (SN), and specifi city (SP) were analyzed using MedCalc software (version 16.1). The research work was carried out within the framework of research of the Department of Pediatrics, Neonatology andPerinatal Medicine of the Bukovinian State Medical University: Research project «Improvement of directions of prognostication, diagnosis and treatment of perinatal pathology in newborns and infants, optimization of schemes of catamnestic observation and rehabilitation» (State registration number 0115U002768, term of implementation 2015-2019); Research project «Chronobiological and adaptive aspects and features of vegetative regulation in pathological conditions in children of diff erent age groups» (State registration number 0122U002245, term of implementation 2020-2024).Study results. The data obtained showed statistically signifi cant associations between the risk of severe renal dysfunctionand a number of antenatal and postnatal factors that adversely aff ect the course of the early neonatal period. These included fetal distress during pregnancy and delivery, emergency cesarean section, risk of spontaneous abortion and preterm birth, and impaired fetal- placental blood fl ow. Statistically signifi cant associations with the development of moderate and severe renal dysfunction are associated with a burdened history of maternal extragenital pathology, namely cardiovascular, urinary system, and anemia (p<0.005). The structure of perinatal pathology in preterm infants is often combined and diffi cult to diagnose.A signifi cant proportion of newborns had clinical manifestations of multiple organ failure syndrome, including signs of renal dysfunction. Therefore, it is expedient to study a set of the latest potential biomarkers of renal dysfunction, such as cystatin C, alpha-1-microglobulin, beta-2-microglobulin and microalbumin, in order to create an appropriate prognostic model and timely form risk groups among this category of children.
 Conclusions. The basis for the development of moderate and severe renal dysfunction in premature infants with perinatalpathology is polyetiology against the background of morphological and functional immaturity of the body, which has a clearrelationship with gestational age and birth weight. The compensatory and adaptive properties of the «immature» kidneys at birth are limited, which, in the presence of combined pathology, plays a signifi cant role in shaping the severity of the course of the disease. Early prognosis and diagnosis of renal dysfunction in the early stages of its development makes it possible to improve the quality and eff ectiveness of medical care and improve treatment outcomes.

Enhancing coal slime processing: Investigating the efficacy of sodium dodecyl sulfonate in the adsorption on kaolinite surfaces

AbstractAddressing the issue of processing fine kaolinite and quartz particles in coal slime, this study utilized molecular simulation and Density Functional Theory (DFT) to investigate the chelate adsorption characteristics of sodium dodecyl sulfate (SDS) on kaolinite surfaces. As a major clay mineral component in coal slime, kaolinite reduces coal's calorific value but holds potential for industrial and agricultural applications. The research identified distinct interactions between SDS and the tetrahedral SiO layer and octahedral AlO layer of kaolinite, in contrast to quartz, which contains only the tetrahedral SiO layer. This difference is crucial for the effective separation of kaolinite from quartz. The study focused on analyzing SDS adsorption on the (001) and (00‐1) planes of kaolinite. The findings revealed strong adsorption of SDS on kaolinite surfaces, especially on the (001) plane, evidenced by significant charge transfer indicating efficient chelation. This effect results from the interaction of SDS's electron‐donating atoms (such as S and O) with the metal atoms on the surface of kaolinite. Adsorption strength was quantified through adsorption energy calculations, showing a stronger interaction on the (001) surface. Experimental validations, including single mineral flotation experiments and infrared spectroscopic analysis, further corroborated the simulation outcomes. These tests demonstrated improved flotation recovery of kaolinite in the presence of SDS and with reduced particle size. Infrared analysis revealed that SDS selectively and strongly adsorbs on kaolinite surfaces, as indicated by diminished hydroxyl group stretching vibrations in the FTIR spectrum and changes in absorption peaks related to inorganic vibrations and sulfonic acid groups. The study demonstrates that SDS can selectively and effectively adsorb onto kaolinite surfaces, particularly on the (001) plane, facilitating the efficient extraction of fine kaolinite from coal slime. This research holds significant potential for enhancing the utilization of resources from coal slime in the coal industry, offering both economic and environmental benefits.

Rapid visual dual-mode detection of Zr(IV) based on L-histidine functionalized gold nanoparticles.

Heavy metal pollution has always been a great threat to human health and safety. Compared with other heavy metals, although zirconium ion (Zr(IV)) is equally harmful, due to the lack of research on Zr(IV) in the biological systems and environment, its detection does not seem to have received the attention it deserves. Herein, a rapid visual dual-mode detection (colorimetric and chrominance method) of Zr(IV) based on L-histidine functionalized gold nanoparticles (HIS-AuNPs) has been reported. AuNPs and HIS-AuNPs before and after adding Zr(IV) were characterized by UV-Vis, TEM, DLS, Zeta potential, EDS and FT-IR, etc. These results showed that L-histidine was successfully modified on the surface of AuNPs by forming a stable Au-N bond, and its modification had little effect on the dispersion degree of AuNPs. After the addition of Zr(IV), interaction of this metal ion with the imidazolyl group on L-histidine can obviously cause the aggregation of HIS-AuNPs within 12min, and the dispersion state and particle size of HIS-AuNPs can be significantly changed. These two detection modes were established by means of absorbance and color change of solution, and being used in addition and recovery experiments of Zr(IV) in natural water. Under the optimal conditions, these two modes exhibited good linearity within 15-70 and 20-100μmolL-1, and limit of detection of 2.62 and 6.25μmolL-1. The proposed method was highly sensitive and selective, which provided a new convenient way to realize the detection of Zr(IV).

Femtosecond optical studies of the primary charge separation reactions in far-red photosystem II from Synechococcus sp. PCC 7335

Primary processes of light energy conversion by Photosystem II (PSII) were studied using femtosecond broadband pump-probe absorption difference spectroscopy. Transient absorption changes of core complexes isolated from the cyanobacterium Synechococcus sp. PCC 7335 grown under far-red light (FRL-PSII) were compared with the canonical Chl a containing spinach PSII core complexes upon excitation into the red edge of the Qy band. Absorption changes of FRL-PSII were monitored at 278 K in the 400–800 nm spectral range on a timescale of 0.1–500 ps upon selective excitation at 740 nm of four chlorophyll (Chl) f molecules in the light harvesting antenna, or of one Chl d molecule at the ChlD1 position in the reaction center (RC) upon pumping at 710 nm. Numerical analysis of absorption changes and assessment of the energy levels of the presumed ion-radical states made it possible to identify PD1+ChlD1− as the predominant primary charge-separated radical pair, the formation of which upon selective excitation of Chl d has an apparent time of ~1.6 ps. Electron transfer to the secondary acceptor pheophytin PheoD1 has an apparent time of ~7 ps with a variety of excitation wavelengths. The energy redistribution between Chl a and Chl f in the antenna occurs within 1 ps, whereas the energy migration from Chl f to the RC occurs mostly with lifetimes of 60 and 400 ps. Potentiometric analysis suggests that in canonical PSII, PD1+ChlD1− can be partially formed from the excited (PD1ChlD1)* state.

Hydrophobic carbon quantum dots with red fluorescence: An optical dual-mode and smartphone imaging sensor for identifying Chinese Baijiu quality

Chinese Baijiu (Liquor) is a popular alcoholic beverage, and the ethanol content in Baijiu is closely related to its quality; therefore, it is of great significance to explore a facile, sensitive, and rapid method to detect ethanol content in Baijiu. Hydrophobic carbon quantum dots (H-CQDs) with bright red fluorescence (24.14 %) were fabricated by hydrothermal method using o-phenylenediamine, p-aminobenzoic acid, manganese chloride, and hydrochloric acid as reaction precursors. After the introduction of ultrapure water into the ethanol solution dissolved with H-CQDs, the aggregated H-CQDs resulted in significant changes in fluorescence intensity and absorbance. On this basis, a sensor for detecting ethanol by optical dual-mode and smartphone imaging was constructed. More importantly, the sensor can be used for detecting ethanol content in Chinese Baijiu with satisfactory results. This sensing platform has great potential for quality identification in Chinese Baijiu, broadening the application scope of CQDs in food safety detection.

Investigating the effects of drying on the physical properties of Kombucha Bacterial Cellulose: Kinetic study and modeling approach

Kombucha bacterial cellulose (KBC), obtained as a by-product of tea fermentation, has potential applications in diverse fields. The high water content and presence of post-fermentation residues necessitate the implementation of suitable drying conditions that can significantly affect the final characteristics of this versatile biopolymer. Thus, to study the effect of different drying methods on its properties, KBC was subjected to microwave drying (180-900 W), hot air oven drying (30-70 °C), and shade drying (25 °C). Additionally, the acquired data were fitted into ten different models to study the drying kinetics of KBC. The dried sheets were then analyzed to study the changes in water absorption and holding capacity, rehydration, surface color, and other physicomechanical properties (UTM, XRD, and contact angle analysis). Hence, optimization of the drying conditions will help reduce the time and cost without compromising any of the intrinsic properties that allow it to be processed into various value-added products.

Growth and metabolic differences in the potential of phytoremediation between two hybrid bermudagrasses in roots, stems, and leaves under cadmium stress

Bermudagrass (Cynodon) species has been identified as a dominant plant species in cadmium (Cd)-contaminated soils. Objectives of current study were to evaluate Cd tolerance of two hybrid bermudagrass (Cynodon transvaalensis × Cynodon dactylon) cultivars Tifdwarf and Chuannong-3 for urban greening and slope ecological restoration and further to explore the difference in Cd tolerance associated with changes in ion absorption and distribution, antioxidant metabolism, and accumulations of phytochelatins (PCs) and metallothioneins (MTs) in roots, stems, and leaves. After exposure to equal concentration and duration of Cd stress, growth, chlorophyll content, and photochemical efficiency of both cultivars reduced significantly, but Cd-induced these inhibitory effects were more pronounced in Chuannong-3. As compared to Chuannong-3, Tifdwarf maintained significantly higher Cd concentration in roots and lower Cd concentration, bioconcentration factor, and translocation factor in aboveground parts in response to Cd stress. Each plant of Tifdwarf also accumulated more Cd in leaves, stems, and roots than each plant of Chuannong-3 due to larger biomass under Cd stress. Cd stress also significantly inhibited uptake and partitioning of iron, sodium, and potassium in two cultivars. In addition, Tifdwarf exhibited better antioxidant defense for reactive oxygen species (ROS) scavenging than Chuannong-3 under Cd stress, as reflected by higher antioxidant enzyme activities and antioxidant metabolites involved in ascorbic acid (ASA)-glutathione (GSH) cycle. Tifdwarf also accumulated more PCs in leaves, stems, and roots and more MTs in leaves and stems than Chuannong-3, which could help to chelate Cd to reduce cytotoxicity of Cd. Moreover, strong antioxidant property of MTs was beneficial for maintaining ROS homeostasis in plants. Therefore, better Cd tolerance of Tifdwarf could be mainly due to the inhibition of Cd uptake and partitioning, enhanced ASA-GSH cycle, and more accumulations of PCs and MTs. Tifdwarf showed better potential for Cd remediation or urban greening in Cd-polluted soils.

Optical properties and radiative forcing of carbonaceous aerosols in a valley city under persistent high temperature

Carbonaceous aerosols were collected in the valley city of Baoji city in Northern China in August 2022. The light absorption characteristics and influencing factors of black carbon (BC) and brown carbon (BrC) were analyzed, and their radiative forcing was estimated. The results showed that the light absorption of secondary brown carbon [AbsBrC,sec (370)] is 7.5 ± 2.4 Mm−1, which is 2.5 times that of primary brown carbon [AbsBrC,pri (370), 3.0 ± 1.2 Mm−1]. During the study period, the absorption Ångström exponent (AAE) of aerosol was 1.6, indicating that there was obvious secondary aerosol formation or carbonaceous aerosol aging in the valley city of Baoji. Except for secondary BrC (BrCsec), the light absorption coefficient (Abs) and mass absorption efficiency (MAE) of BC and BrC (BrCpri) during the persistent high temperature period (PHT) were higher than those during the normal temperature period (NT) and the precipitation period (PP), which indicated that the light absorption capacity of black carbon and primary brown carbon increased, while the light absorption of secondary brown carbon decreased under persistent high temperature period. Secondary aerosols sulfide (SO42−), nitrate (NO3−) and secondary organic carbon (SOC) are important factors for promoting BC and BrCpri light absorption enhancement and photobleaching of BrCsec during persistent high temperature period. The Principal Component Analysis-Multiple Linear Regression (PCA-MLR) model showed that traffic emissions are the most important source of pollution in Baoji City. Based on this, the secondary atmospheric reaction accelerates the aging of BC and BrC, causing changes in light absorption. During PHT, the radiative forcing of BC is enhanced, while the radiative forcing of BrCsec is weakened, but the positive radiative forcing generated by them may aggravate the high-temperature disaster.

High piezoelectric coefficients and rich phase transitions in ternary TlXY (X = S, Se; Y = Cl, Br, I) monolayers

In this work, we investigated the structural, electronic, optical, and piezoelectric properties of TlXY (X = S, Se; Y = Cl, Br, I) monolayers using the first-principles calculations. Five types of TlXY monolayers are structurally stable. The band gap, which ranges from 0.371-2.196 eV, is direct for most TlXY and indirect for TlSeBr. With adequate flexibility, the in-plane and out-of-plane piezoelectric coefficients, d11 and d31, of TlXY can approach 77.05-90.55 pm/V and 0.70-1.08 pm/V, respectively, which is larger than those of reported 2D materials. Strain can cause a direct-to-indirect band gap transition or even a topological phase transition. Furthermore, TlSeBr and TlSI can undergo structural phase transitions, resulting in dramatic changes in electronic structure and optical absorption. Our results suggest 2D TlXY as a series of promising materials for optoelectronic and piezoelectric applications.

Terahertz-triggered ultrafast nonlinear optical activities in two-dimensional centrosymmetric PtSe2.

The nonlinear mechanisms of polarization and optical fields can induce extensive responses in materials. In this study, we report on two kinds of nonlinear mechanisms in the topological semimetal PtSe2 crystal under the excitation of intense terahertz (THz) pulses, which are manipulated by the real and imaginary parts of the nonlinear susceptibility of PtSe2. Regarding the real part, the broken inversion symmetry of PtSe2 is achieved through a THz-electric-field polarization approach, which is characterized by second harmonic generation (SHG) measurements. The transient THz-laser-induced SHG signal occurs within 100 fs and recombines to the equilibrium state within 1 ps, along with a high signal-to-noise ratio (∼51 dB) and a high on/off ratio (∼102). Regarding the imaginary part, a nonlinear absorption change can be generated in the media. We reveal a THz-induced absorption enhancement in PtSe2 via nonlinear transmittance measurements, and the sheet conductivity can be modulated up to 42% by THz electric fields in our experiment. Therefore, the THz-induced ultrafast nonlinear photoresponse reveals the application potential of PtSe2 in photonic and optoelectronic devices in the THz technology.

In Vitro Study of the Surface Roughness, Hardness, and Absorption of an Injection-Molded Denture Base Polymer, Manufactured under Insufficient Mold Solidification

The current study sought to investigate the changes in surface hardness, roughness, and moisture absorption of the Vertex ThermoSens polymer (Vertex Dental, 3D Systems, The Netherlands) following immersion in artificial saliva for various periods (7, 14, and 28 days). A total of 60 rectangular specimens with dimensions of 20 mm in length, 20 mm in width, and 3 mm in thickness were made. Due to insufficient mold solidification, these specimens were made utilizing the injection molding process. A Mitutoyo Surftest 4 roughness meter (Mitutoyo, Aurora, IL, USA) was used to measure the surface roughness of the test materials. The ThermoSens polymer hardness was assessed using the Shor method and D—HSD scale, while absorption was measured with a Sartorius analytical balance. Results indicated the highest mean hardness after 28 days (M = 77.6) (Surface 1) and the lowest for the control group (M = 59) (Surface 2). The maximum surface roughness occurred in direction 2.2 pre-immersion (Ra = 2.88 μm) and 7 days post-removal (Ra = 2.95 μm). The control group exhibited the lowest absorption (Wsp = 1.524 mg/mm3), with the highest mean values over 28 days (Wsp = 1.541 mg/mm3). The elevated flask and plaster temperature slowed polymer solidification, resulting in longer macromolecules and improved mechanical properties and surface features.

Sensitivity and Selectivity Detection Studies of Fe (III) Using Cu(I) Complex of Schiff Base Material

The liver, bones, kidneys, teeth, and central nervous system sustain serious damage as a result of heavy metal ions entering the human food chain. In order to improve public health, new techniques must be developed for the rapid, easy, simple, reliable, low-cost, and reliable identification of toxic metal ions.Naked eye detection of hazardous metal ions with Cu (I) fluorescent properties of Cu(I) Complex of with 2, 2′-bipyridine and trans cinnamic acid were investigated. The structure of the fluorescent Cu (I) complex was characterized by conductivity measurement, elemental analysis, UV-Visible and FT-IR. The Cu (I) complex was soluble in dimethylsulfoxide, distilled water, methanol and insoluble in tetrahydrofuran. In the applications, firstly the color of the Cu(I) complex was compared with/without metal ions, and then the measurements were made in the UV-Vis spectrophotometer to exhibit selective and sensitive to Fe3+ ions in DMSO (dimethylsulfoxide) / H2O (water) (v/v, 1:1). Cu(I) complex exhibited absorbance band at 323 nm in dimethylsulfoxide. The absorbance intensity was decreased by Fe (III) and behaves as a turn-off sensor. The sensor showed high selectively and sensitivity toward Fe (III) over the other cations in dimethlsulfoxide solution. The equilibrium binding constant of Cu (I) complex with Fe (III) was 1.9x10 4 M -1 as calculated using stern –volmer equation. The limit of detection was also determined and calculated as 0.219 μM. Based on facts obtained from this study, the author suggests the Copper (I) complex response to Fe (III) rapidly and a large number of consecutive ions showed almost no obvious absorbance change during detection. Copper (I) complex could act as cost effective, selective, specific and sensor for detection of Fe (III) ions over other metal ions.

Tailored isatin-derived chemosensor immobilized on silica nanoparticles for targeted detection of Ni(II) ion

In this study, we have designed and synthesized a chemosensor, isatin-based triazole-linked silanes (ITS), employing the Cu(I)-catalyzed Azide-Alkyne cycloaddition reaction (CuAAC) and the synthesized silanes has been well characterized through various analytical techniques, including FT-IR, 1H NMR, 13C NMR, and ESI-MS. The developed sensor exhibited the capability to detect Ni2+ ion in a methanol/water solution (9:1, v/v) by manifesting different absorbance changes and fluorescence. In the fluorescence mode, the addition of Ni2+ ion triggers a “Turn-OFF” response in the sensor, demonstrating an ultratrace detection limit of 2.49 × 10−7 M. Successful grafting of organosilane onto silica nanoparticles has been achieved, and these new silane-coated nanoparticles demonstrate enhanced sensing abilities for Ni2+ ions, with a detection limit of 1.56 × 10−8 M. Stoichiometric data reveals a 1:1 coordination between the sensor and Ni2+ ion. Furthermore, both the synthesized alkyne and silane underwent examination for their drug-likeness profiles, providing valuable insights.

Effect of subchronic exposure to manganese on mineral metabolism in Wistar rats

Background. The presence of increased manganese concentrations in soils and water intakes areas for drinking and household purposes in a number of the Russian Federation subjects indicates the  chronic influence of this metal on all segments of the population. This situation is aggravated by violation of the optimal nutrition principles, which leads to changes in the organism absorption of micronutrients. In this regard, the study of the elemental status of an organism against the background of manganese exposure is of particular importance.The aim. To study the effects of subchronic exposure to manganese on the mineral status of Wistar rats.Materials and methods. To  conduct the study, 20  mature rats were selected, from which two groups were formed – control (n = 10) and experimental (n = 10). Animals in the control group received a general diet, animals in the experimental group received a diet with additional administration of manganese sulfate at a dose of 1433 mg/kg for 28 days. At the end of the preparatory period, blood and brain samples were taken to determine the content of chemical elements using inductively coupled plasma mass spectrometry and of metal-ligand manganese forms using high-performance liquid chromatography combined with inductively coupled plasma mass spectrometry.Results. It has been established that subchronic oral exposure to manganese leads to an increase in the content of this microelement in the blood serum and to a decrease in the levels of calcium, potassium, magnesium, iron and copper. In the cerebral cortex, the level of manganese, lead, mercury and strontium increases against the background of a decrease in iron and iodine levels. An increase in the gross content of manganese in blood serum leads to an overload of the main high-molecular carriers and initiates the formation of low-molecular forms of manganese.Conclusion. Subchronic oral exposure to manganese leads to the accumulation of this microelement in the body of animals and to the development of an imbalance of a number of macro- and microelements.

A hybrid density functional study of tensile-induced changes in phonon dispersion, electronic structure and optical absorption of bilayer BN for optoelectronic applications

The electronic, phonon dispersion and optical properties of bilayer BN have been investigated with density functional theory (DFT) calculations. Interestingly, applying the biaxial strain of 4% converts the indirect band gap of bilayer BN to a direct band gap. We show that the interaction between the BN layers results in the removal of two-fold degeneracy and separation of ZA and ZO phonon modes near the Γ point. Across the entire range of applied biaxial tensile strains, the bilayer BN exhibits a dynamically stable behavior. The phonon bandgap of bilayer BN decreases under tensile strain. The bilayer BN has strong adsorption in the UV region and the optical absorption peaks are red-shifted by applying the tensile strain. These findings are essential for the strain engineering of bilayer BN and future fabrication of flexible electronic and optoelectronic devices.

Impact of Drug-Mediated Inhibition of Intestinal Transporters on Nutrient and Endogenous Substrate Disposition…an Afterthought?

A large percentage (~60%) of prescription drugs and new molecular entities are designed for oral delivery, which requires passage through a semi-impervious membrane bilayer in the gastrointestinal wall. Passage through this bilayer can be dependent on membrane transporters that regulate the absorption of nutrients or endogenous substrates. Several investigations have provided links between nutrient, endogenous substrate, or drug absorption and the activity of certain membrane transporters. This knowledge has been key in the development of new therapeutics that can alleviate various symptoms of select diseases, such as cholestasis and diabetes. Despite this progress, recent studies revealed potential clinical dangers of unintended altered nutrient or endogenous substrate disposition due to the drug-mediated disruption of intestinal transport activity. This review outlines reports of glucose, folate, thiamine, lactate, and bile acid (re)absorption changes and consequent adverse events as examples. Finally, the need to comprehensively expand research on intestinal transporter-mediated drug interactions to avoid the unwanted disruption of homeostasis and diminish therapeutic adverse events is highlighted.

Tailoring the physicochemical properties of starch: impact of integrated ultrasonic and ethanol pretreatment on the oil uptake of infrared fried ginkgo seeds.

The structural changes of starch would have a more crucial impact on oil absorption and quality changes in starch-rich fruits and vegetables during frying process with enhanced heat transfer (such as infrared frying). In the present study, the influence of integrated ultrasonic and ethanol (US + ethanol) pretreatment on oil uptake in infrared fried (IF) ginkgo seeds was evaluated regarding modifications in the physicochemical properties of starch. The pretreatment was performed with ultrasonic (40 kHz, 300 W) and ethanol osmotic (95%, v/v) treatment individually or integrated for 40 min. The mass transfer in the pretreatment was facilitated by combined ultrasound and ethanol. The swelling power, solubility, and gelatinization degree of starch was significantly increased. Low-frequency-NMR curves and images revealed that the bound water fraction in ginkgo seeds was increased and the water distribution was homogenized. The results of Fourier transform-infrared spectrum and differential scanning calorimeter revealed that the crystalline regions of starch were reduced and the thermal enthalpy was decreased after US + ethanol pretreatment. The total, surface and structural oil content in IF ginkgo seeds with US + ethanol pretreatment was reduced by 29.10%, 34.52% and 29.73%, respectively. The US + ethanol pretreatment led to a thinner crust layer with increased porosity and smaller-sized pores in the IF ginkgo seeds as observed by stereo microscopy and scanning electron microscopy. The changes in structural and physicochemical properties of starch by combined ultrasound and ethanol affect the crust ratio and pore characteristics in fried high-starch fruits and vegetables, thereby reducing oil absorption. © 2024 Society of Chemical Industry.