Complex Response Research Articles

Physical and Chemical Parameters in Assessment of Metabolic Profiles of Patients With B

Objective: To study catalytic properties of lactate dehydrogenase (LDH) and some physical and chemical characteristics of blood in patients with thermal injuries.Materials and methods: We examined blood samples from 24 patients with contact burns involving 10%-40% of the body surface area and studied erythrocyte LDH activity in forward and reverse reactions, kinetic characteristics of this process, and protein concentration. We used teziocrystalloscopy to evaluate crystallogenic properties of blood serum of the examined patients with thermal injuries.Results: Thermal injuries were shown to cause a 2-fold decrease in LDH activity in the reverse reaction. Analysis of crystallogenic properties of blood serum of the patients with contact burns revealed that development of a complex response to a burn injury is accompanied by a moderate decrease in the structure index and crystallizability and a signifi decrease in the clearity of the marginal protein zone. In case of burn disease, we also observed a decrease in the initiative potential of the biological fl In addition, microscope slides of the dried blood serum revealed a tendency to randomization of the sample similar to that found in crystalloscopic facies.Conclusions: The local thermal effect leading to a complex response to a burn injury was found to cause significant transformation of physical and chemical characteristics of blood. Thermal injuries cause a decrease in LDH activity in the reverse reaction leading to a disturbance of the lactate-to-pyruvate ratio in the cell and significant shifts in the blood serum composition and properties, which are manifested in a significant change in blood serum crystallogenic and initiating properties.

A computational study on the second-order nonlinear optical response of a new unsymmetrical oxovanadium complex

A new unsymmetrical N2O2 Schiff base oxovanadium (IV) complex, VOLPy, was synthesized with excellent yield and characterized using conventional methods. The crystal structure of the VOLPy complex was determined through X-ray diffraction, revealing a distorted square pyramidal coordination configuration around the central vanadium ion. The solid-state structure is stabilized by various non-covalent short contacts, generating complex 3D supramolecular network. The electrochemical properties of the VOLPy complex were investigated in different media, demonstrating diffusion-controlled reversible or quasi-reversible processes within the potential range of 200–1000 mV, involving a single electron VV/VIV reduction. The diffusion coefficients were calculated using Levich plots Ilim = f(ω1/2). Using quantum calculations at the CAM-B3LYP level with a 6-311G**/LanL2DZ basis set, we systematically assessed various structural parameters, electronic properties, linear and nonlinear optical responses at static and dynamic regimes for oxovanadium complexes, V(V)OL and V(IV)OL, in both gaseous and solvent environments. The results reveal a robust alignment between quantum calculations and experimental data, with only minor deviations. This study anticipates that these specifically designated complexes hold substantial potential as excellent candidates for second-order nonlinear optical (NLO) materials.

Hospitality Discourse on Social Media: Evaluating Online Complaints and Service Recovery for Luxury Hotels

The number of hotel visitors who post their personal experiences on online hotel review forums after their trips has increased significantly in the digital age. However, there is limited linguistic research that examines 1) how international travelers communicate online to share their negative hotel experiences and 2) how luxury hotel management resolves complaints and regains customer trust. This study examines electronic word-of mouth (eWOM) in the reviews and focuses on posted by international travelers who stayed at Hong Kong's 5-star luxury hotels and e-replies posted by hotel management groups. The data are based on authentic reviews collected from an online travel review forum. The present study employs appraisal analysis (Martin & White, 2005) and specifically the engagement system to investigate heteroglossic voice in 38 sets of complex e-complaints and responses totaling 17,344 words. The findings contribute to the advancement of professional discourse in hospitality service encounters.

Exploring on the prediction model of human skin temperature and rectal temperature under heat stress

Hot environments cast direct influence on people's well-beings and health besides working productivity during the accelerating global warming. The systematic mechanism is not entirely clear due to the complex human physiological response which also handled human heat strain protection. This study carries out mathematical derivation on the rectal temperature and skin temperature under human heat strain based on the PHS model of ISO 7933 standard. The experimental validation was conducted in a climate chamber with continuously monitoring the typical physiological parameters of 10 subjects in 9 hot working environments. Physiological parameters of subjects were analyzed on average difference (AV), coefficient of variation (CV) and skewness (SKEW) to explore their mutual linkages. Both experimental and theoretical result shows that certain relationship existed between the rectal temperature and skin temperature. The Poisson's ratio on their average value, coefficient of variation, average difference and skew were 0.957, 0.991, 0.990 and 0.941 respectively. Linear relation with coefficient of 0.73 was found between rectal temperature and skin temperature coupling with the constant of 12.09. Comparison on the dynamic changes of rectal temperature and skin temperature was carried out and verified under PHS model. The results showed that rectal temperature was adjusted earlier and more forcefully than skin temperature indicating that human core temperature was better protected under heat stress. The findings contribute to a convenient method of human heat strain prediction when taking rectal temperature as the best physiological threshold with fast human skin temperature and environment parameters monitoring in complex high temperature working environments.

EXPERIMENTAL STUDY OF THE LATERAL RESISTANCE OF CFS SHEAR WALLS

AbstractIn recent years, the attention grew toward sustainability issues. This led to the popularity of residential buildings made of cold formed steel profiles. In these systems the lateral bracing is provided by the shear walls. Their complex response calls for the design by testing approach. At the University of Trento an experimental study is in progress of the shear wall response under monotonic and cyclic loading. Five shear wall configurations differing in the steel skeleton and sheathings type are comprised in the programme. The paper presents the main features of the testing set‐up and the preliminary results related to two shear wall configurations. The key role of sheathing‐to‐steel framing connections is pointed out.

Parameterizing Raindrop Formation Using Machine Learning

Abstract Raindrop formation processes in warm clouds mainly consist of condensation and collision–coalescence of small cloud droplets. Once raindrops form, they can continue growing through collection of cloud droplets and self-collection. In this study, we develop novel emulators to represent raindrop formation as a function of various physical or background environmental conditions by using a sophisticated aerosol–cloud model containing 300 droplet size bins and machine learning methods. The emulators are then implemented in two microphysics schemes in the Weather Research and Forecasting Model and tested in two idealized cases. The simulations of shallow convection with the emulators show a clear enhancement of raindrop formation compared to the original simulations, regardless of the scheme in which they were embedded. On the other hand, the simulations of deep convection show a more complex response to the implementation of the emulators, in terms of the changes in the amount of rainfall, due to the larger number of microphysical processes involved in the cloud system (i.e., ice-phase processes). Our results suggest the potential of emulators to replace the conventional parameterizations, which may allow us to improve the representation of physical processes at an affordable computational expense. Significance Statement Formation of raindrops marks a critical stage in cloud evolution. Accurate representations of raindrop formation processes require detailed calculations of cloud droplet growth processes. These calculations are often not affordable in weather and climate models as they are computationally expensive due to their complex dependence on cloud droplet size distributions and dynamical conditions. As a result, simplified parameterizations are more frequently used. In our study we trained machine learning models to learn raindrop formation rates from detailed calculations of cloud droplet evolutions in 1000 parcel-model simulations. The implementation of the developed models or the emulators in a weather forecasting model shows a change in the total rainfall and cloud characteristics, indicating the potential improvement of cloud representations in models if these emulators replace the conventional parameterizations.

Dynamic responses of Fusarium mangiferae to ultra-violet radiation

The repair capacity of ultra-violet (UV) light DNA damage is important for adaptation of fungi to different ecological niches. We previously showed that in the soil-borne pathogen Fusarium oxysporum photo-reactivation dependent UV repair is induced at the germling stage and reduced at the filament stage. Here, we tested the developmental control of the transcription of photolyase, UV survival, UV repair capacity, and UV induced mutagenesis in the foliar pathogen Fusarium mangiferae. Unlike F. oxysporum, neither did we observe developmental control over photo-reactivation dependent repair nor the changes in gene expression of photolyase throughout the experiment. Similarly, photo-reactivation assisted reduction in UV induced mutagenesis was similar throughout the development of F. mangiferae but fluctuated during the development of F. oxysporum. To generate hypotheses regarding the recovery of F. mangiferae after UV exposure, an RNAseq analysis was performed after irradiation at different timepoints. The most striking effect of UV on F. mangiferae was developmental-dependent induction of translation related genes. We further report a complex response that changes during recovery time and involves translation, cell cycle and lipid biology related genes.

Modeling T cell temporal response to cancer immunotherapy rationalizes development of combinatorial treatment protocols.

Successful immunotherapy relies on triggering complex responses involving T cell dynamics in tumors and the periphery. Characterizing these responses remains challenging using static human single-cell atlases or mouse models. To address this, we developed a framework for in vivo tracking of tumor-specific CD8+ T cells over time and at single-cell resolution. Our tools facilitate the modeling of gene program dynamics in the tumor microenvironment (TME) and the tumor-draining lymph node (tdLN). Using this approach, we characterize two modes of anti-programmed cell death protein 1 (PD-1) activity, decoupling induced differentiation of tumor-specific activated precursor cells from conventional type 1 dendritic cell (cDC1)-dependent proliferation and recruitment to the TME. We demonstrate that combining anti-PD-1 therapy with anti-4-1BB agonist enhances the recruitment and proliferation of activated precursors, resulting in tumor control. These data suggest that effective response to anti-PD-1 therapy is dependent on sufficient influx of activated precursor CD8+ cells to the TME and highlight the importance of understanding system-level dynamics in optimizing immunotherapies.

A Review on Anthropogenic Biomass Burning: Emission of Aerosol Pollutants, Impact on Climate Change, Human Health and its Mitigation Strategies

Biomass burning is a complex process, encircling chemical and physical responses covering, transmission of mass and warmth. A large number of investigations were accumulated on the significant emissions from various kinds of anthropogenic biomass burning in the recent decade. In India, an increasing trend of biomass burning is an important cause to release a large volume of reactive gases with other impurities and intensify the level of invisible particles into the troposphere, which affects humans health and leads to the probable alteration of the weather and global climate. The present review looks at the interpretations for a diverse investigation of distinct body and monitoring interventions, pertinent to our country, relating to the significance of particulate matter emissions, sources of aerosols and their health implications. This study also discusses numerous persuaded investigations, conducted on the impact of aerosol, attributed to climate change and also points out precise matters such as spatio-temporal variability of fire occurrences detected in India. Furthermore, the present study reveals that substantial quantities of data, along with a variety of enhanced simulation models and investigational validations, are essential for the development of efficient mitigation strategies with the objective of protecting the environment of the Indian Peninsula.

A Protective Role of Canonical Wnt/β-Catenin Pathway in Pathogenic Bacteria-Induced Inflammatory Responses.

Inflammation is a complex host defensive response against various disease-associated pathogens. A baseline extent of inflammation is supposed to be tightly associated with a sequence of immune-modulated processes, resulting in the protection of the host organism against pathogen invasion; however, as a matter of fact is that an uncontrolled inflammatory cascade is the main factor responsible for the host damage, accordingly suggesting a significant and indispensable involvement of negative feedback mechanism in modulation of inflammation. Evidence accumulated so far has supported a repressive effect of the canonical Wnt/β-catenin pathway on microbial-triggered inflammation via diverse mechanisms, although that consequence is dependent on the cellular context, types of stimuli, and cytokine environment. It is of particular interest and importance to comprehend the precise way in which the Wnt/β-catenin pathway is activated, due to its essential anti-inflammatory properties. It is assumed that an inflammatory milieu is necessary for initiating and activating this signaling, implying that Wnt activity is responsible for shielding tissues from overwhelming inflammation, thus sustaining a balanced physiological condition against bacterial infection. This review gathers the recent efforts to elucidate the mechanistic details through how Wnt/β-catenin signaling modulates anti-inflammatory responses in response to bacterial infection and its interactions with other inflammatory signals, which warrants further study for the development of specific interventions for the treatment of inflammatory diseases. Further clinical trials from different disease settings are required.

Segmented multifractal detrended fluctuation analysis for assessing inefficiency in North African stock markets

This study employs segmented multifractal analysis to evaluate the efficiency of key financial markets in North Africa. The proposed method, an adapted version of Multifractal Detrended Fluctuation Analysis (MF-DFA), integrates a wavelet-based change-point detection to identify and separate the two most dynamically changing phases. Subsequent multifractal measurements are then conducted for each of these identified intervals. Focusing on three equity indices—the Egyptian Exchange Index (EGX30), Moroccan All Shares Index (MASI), and Tunisian Stock Index (Tunindex)–that collectively represent the North African financial and economic landscape, empirical results reveal significant asymmetric multifractality, especially notable in the two Maghreban indices. These findings prompt inquiries into the influence of major events on financial market efficiency. Segmented multifractal analysis introduces a novel approach to explore the dynamics and resilience of these sectors, contributing to a more profound understanding of their complex behaviors and responses to various stimuli.

Trophic cascades within and across ecosystems: The role of anti-predatory defences, predator type and detritus quality.

Species in one ecosystem can indirectly affect multiple biodiversity components and ecosystem functions of adjacent ecosystems. The magnitude of these cross-ecosystem effects depends on the attributes of the organisms involved in the interactions, including traits of the predator, prey and basal resource. However, it is unclear how predators with cross-ecosystem habitat interact with predators with single-ecosystem habitat to affect their shared ecosystem. Also, unknown is how such complex top-down effects may be mediated by the anti-predatory traits of prey and quality of the basal resource. We used the aquatic invertebrate food webs in tank bromeliads as a model system to investigate these questions. We manipulated the presence of a strictly aquatic predator (damselfly larvae) and a predator with both terrestrial and aquatic habitats (spider), and examined effects on survival of prey (detritivores grouped by anti-predator defence), detrital decomposition (of two plant species differing in litter quality), nitrogen flux and host plant growth. To evaluate the direct and indirect effects each predator type on multiple detritivore groups and ultimately on multiple ecosystem processes, we used piecewise structural equation models. For each response variable, we isolated the contribution of different detritivore groups to overall effects by comparing alternate model formulations. Alone, damselfly larvae and spiders each directly decreased survival of detritivores and caused multiple indirect negative effects on detritus decomposition, nutrient cycling and host plant growth. However, when predators co-occurred, the spider caused a negative non-consumptive effect on the damselfly larva, diminishing the net direct and indirect top-down effects on the aquatic detritivore community and ecosystem functioning. Both detritivore traits and detritus quality modulated the strength and mechanism of these trophic cascades. Predator interference was mediated by undefended or partially defended detritivores as detritivores with anti-predatory defences evaded consumption by damselfly larvae but not spiders. Predators and detritivores affected ecosystem decomposition and nutrient cycling only in the presence of high-quality detritus, as the low-quality detritus was consumed more by microbes than invertebrates. The complex responses of this system to predators from both recipient and adjacent ecosystems highlight the critical role of maintaining biodiversity components across multiple ecosystems.

Mechanism exploration and biomarker identification of glycemic deterioration in patients with diseases of the exocrine pancreas

The damage to the endocrine pancreas among patients with diseases of the exocrine pancreas (DP) leads to reduced glycemic deterioration, ultimately resulting in diabetes of the exocrine pancreas (DEP). The present research aims to investigate the mechanism responsible for glycemic deterioration in DP patients, and to identify useful biomarkers, with the ultimate goal of enhancing clinical practice awareness. Gene expression profiles of patients with DP in this study were acquired from the Gene Expression Omnibus database. The original study defines DP patients to belong in one of three categories: non-diabetic (ND), impaired glucose tolerance (IGT) and DEP, which correspond to normoglycemia, early and late glycemic deterioration, respectively. After ensuring quality control, the discovery cohort included 8 ND, 20 IGT, and 12 DEP, while the validation cohort included 27 ND, 15 IGT, and 20 DEP. Gene set enrichment analysis (GSEA) employed differentially expressed genes (DEGs), while immunocyte infiltration was determined using single sample gene set enrichment analysis (ssGSEA). Additionally, correlation analysis was conducted to establish the link between clinical characteristics and immunocyte infiltration. The least absolute shrinkage and selection operator regression and random forest combined to identify biomarkers indicating glycemic deterioration in DP patients. These biomarkers were further validated through independent cohorts and animal experiments. With glycemic deterioration, biological processes in the pancreatic islets such as nutrient metabolism and complex immune responses are disrupted in DP patients. The expression of ACOT4, B2M, and ACKR2 was upregulated, whereas the expression of CACNA1F was downregulated. Immunocyte infiltration in the islet microenvironment showed a significant positive correlation with the age, body mass index (BMI), HbA1c and glycemia at the 2-h of patients. It was a crucial factor in glycemic deterioration. Additionally, B2M demonstrated a significant positive correlation with immunocyte infiltration and clinical features. Quantitative real-time PCR (qRT-PCR) and western blotting confirmed the upregulation in B2M. Immunofluorescent staining suggested the alteration of B2M was mainly in the alpha cells and beta cells. Overall, the study showed that gradually increased immunocyte infiltration was a significant contributor to glycemic deterioration in patients with DP, and it also highlighted B2M as a biomarker.

Disentangling optical effects in 3D spiral-like, chiral plasmonic assemblies templated by a dark conglomerate liquid crystal.

Chiral thin films showing electronic and plasmonic circular dichroism (CD) are intensively explored for optoelectronic applications. The most studied chiral organic films are the composites exhibiting a helical geometry, which often causes entanglement of circular optical properties with unwanted linear optical effects (linearly polarized absorption or refraction). This entanglement limits tunability and often translates to a complex optical response. This paper describes chiral films based on dark conglomerate, sponge-like, liquid crystal films, which go beyond the usual helical type geometry, waiving the problem of linear contributions to chiroptical electronic and plasmonic properties. First, we show that purely organic films exhibit high electronic CD and circular birefringence, as studied in detail using Mueller matrix polarimetry. Analogous linear properties are two orders of magnitude lower, highlighting the benefits of using the bi-isotropic dark conglomerate liquid crystal for chiroptical purposes. Next, we show that the liquid crystal can act as a template to guide the assembly of chemically compatible gold nanoparticles into 3D spiral-like assemblies. The Mueller matrix polarimetry measurements confirm that these composites exhibit both electronic and plasmonic circular dichroisms, while nanoparticle presence is not compromising the beneficial optical properties of the matrix.

Cardiopulmonary Exercise Testing in Heart Failure.

Cardiopulmonary exercise testing (CPET) provides important information for the assessment and management of patients with heart failure. This testing measures the respiratory and cardiac responses to exercise and allows measurement of the oxygen uptake (V˙O2) max and the relationship between minute ventilation (V˙E) and carbon dioxide excretion (V˙CO2). These two parameters help classify patients into categories that help predict prognosis, and patients with a V˙O2 < 14 mL/kg/min and V˙E/V˙CO2 slope >35 have a poor prognosis. This testing has been used in drug trials to determine complex physiologic responses to medications, such as angiotensin-converting enzyme inhibitors. For example, a study with enalapril demonstrated that the peak V˙O2 was 14.6 ± 1.6 mL/kg/min on placebo and 15.8 ± 2.0 mL/kg/min on enalapril after 15 days of treatment. The V˙E/V˙CO2 slopes were 43 ± 8 on placebo and 39 ± 7 on enalapril. Chronic heart failure and reduced physical activity measured by cardiopulmonary exercise testing are associated with increases in BNP, and several studies have demonstrated that cardiac rehabilitation is associated with reductions in BNP and increases in V˙O2. Therefore, BNP measurements can help determine the benefits of cardiac rehabilitation and provide indirect estimates of changes in V˙O2. In addition, measurement of microRNAs can determine the status of skeletal muscle used during physical activity and the changes associated with rehabilitation. However, CPET requires complicated technology, and simpler methods to measure physical activity could help clinicians to manage their patients. Recent advances in technology have led to the development of portable cardiopulmonary exercise testing equipment, which can be used in various routine physical activities, such as walking upstairs, sweeping the floor, and making the bed, to provide patients and clinicians a better understanding of the patient's current symptoms. Finally, current smart watches can provide important information about the cardiorespiratory system, identify unexpected clinical problems, and help monitor the response to treatment. The organized use of these devices could contribute to the management of certain aspects of these patients' care, such as monitoring the treatment of atrial fibrillation. This review article provides a comprehensive overview of the current use of CPET in heart failure patients and discusses exercise principles, methods, clinical applications, and prognostic implications.

Investigation of Potential Effects of Ibuprofen on the Storage Cells and Anhydrobiosis Capacity of the Tardigrade Paramacrobiotus experimentalis

The surge in pharmaceutical consumption, particularly non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, has raised concerns about their presence in aquatic ecosystems. This study investigated the potential ecological impact of ibuprofen, focusing on the ultrastructure of storage cells in the tardigrade Paramacrobiotus experimentalis, renowned for its resilience to environmental stressors. Individuals were exposed to three ibuprofen concentrations (0.1 μg/L, 16.8 μg/L, and 1 mg/L) over 7 and 28 days. Storage cells were examined using light microscopy, transmission electron microscopy, and confocal microscopy. This study also explored ibuprofen’s impact on the process of anhydrobiosis. In the short-term experiment, no ultrastructural changes in tardigrade storage cells were observed across ibuprofen concentrations. However, in the long-term incubation, autophagic structures in storage cell cytoplasm were identified, indicating potential adaptive responses. Individual mitochondria exhibited degeneration, and the rough endoplasmic reticulum displayed slight swelling. No evidence of increased oxidative stress or nuclear DNA fragmentation was observed in any research group. This study elucidates the complex responses of tardigrade storage cells to ibuprofen exposure. The findings emphasize the importance of understanding pharmaceutical impacts on aquatic organisms, highlighting the resilience of tardigrades to specific environmental stressors.

Genome-Wide Analysis of Aux/IAA Gene Family in Artemisia argyi: Identification, Phylogenetic Analysis, and Determination of Response to Various Phytohormones.

Artemisia argyi is a traditional herbal medicine plant, and its folium artemisia argyi is widely in demand due to moxibustion applications globally. The Auxin/indole-3-acetic acid (Aux/IAA, or IAA) gene family has critical roles in the primary auxin-response process, with extensive involvement in plant development and stresses, controlling various essential traits of plants. However, the systematic investigation of the Aux/IAA gene family in A. argyi remains limited. In this study, a total of 61 Aux/IAA genes were comprehensively identified and characterized. Gene structural analysis indicated that 46 Aux/IAA proteins contain the four typical domains, and 15 Aux/IAA proteins belong to non-canonical IAA proteins. Collinear prediction and phylogenetic relationship analyses suggested that Aux/IAA proteins were grouped into 13 distinct categories, and most Aux/IAA genes might experience gene loss during the tandem duplication process. Promoter cis-element investigation indicated that Aux/IAA promoters contain a variety of plant hormone response and stress response cis-elements. Protein interaction prediction analysis demonstrated that AaIAA26/29/7/34 proteins are possibly core members of the Aux/IAA family interaction. Expression analysis in roots and leaves via RNA-seq data indicated that the expression of some AaIAAs exhibited tissue-specific expression patterns, and some AaIAAs were involved in the regulation of salt and saline-alkali stresses. In addition, RT-qPCR results indicated that AaIAA genes have differential responses to auxin, with complex response patterns in response to other hormones, indicating that Aux/IAA may play a role in connecting auxin and other hormone signaling pathways. Overall, these findings shed more light on AaIAA genes and offer critical foundational knowledge toward the elucidation of their function during plant growth, stress response, and hormone networking of Aux/IAA family genes in A. argyi.

Biotic pathways of reciprocal responses between antibiotic resistance genes and inorganic nitrogen cycling genes in amoxicillin-stressed compost ecosystems

This study explored the transformation of inorganic nitrogen, the expression levels of antibiotic resistance genes (ARGs), and the regulatory mechanisms of key species on ARGs and inorganic nitrogen cycling genes (INCGs) under different levels of amoxicillin (AMX) stress. High level of AMX inhibited the accumulation of NH4+-N, which increased by 531 % relative to the initial. Moreover, AMX to some extent increased the levels of nirS and nirK, which could potentially result in nitrogen loss and the accumulation of NO2–. Actinobacteria might serve as potential hosts for ARGs during sludge composting. This stress induced a complex response between INCGs and ARGs more complex due to key species. Under high-level AMX pressure, most species associated with ARGs likely derived from nitrogen cycling functional species. To conclude, high levels of AMX stress might lead to nitrogen cycling imbalance and the dissemination of antibiotic resistance genes in composting systems.

Selective fluoride detection based on modulation of red emissive carbon dots fluorescence by zirconium-alizarin complex: Application to Nile River water and human saliva samples

Fluoride is an essential ion for dental health that is optimally supplemented through drinking water, toothpastes, and other oral hygiene products. This work reports a selective, simple, and inexpensive fluorescent sesnor for fluoride quantification. The sensor exploits the red fluorescence of carbon dots coupled with the colorimetric response of a zirconium-alizarin complex. The zirconium-alizarin exhibits an absorption band at 530 nm that overlaps the carbon dot excitation peak, resulting in inner filter effect-based quenching of the 612 nm red emission. However, in the presence of fluoride, binding disrupts the zirconium complex, releasing free alizarin with an absorption blue shifted to 420 nm. This reduces spectral overlap and restores carbon dot fluorescence. The carbon dots were synthesized by a hydrothermal method and exhibited excellent fluorescence quantum yield (16.3 %). Structural and optical characterizations were performed using TEM, XRD, XPS, FTIR, UV–vis, and fluorescence techniques. Under optimized conditions, the probe provided selective turn-on fluorescence detection of fluoride with a linear response from 1.0 to 130.0 μM and limit of detection (S/N = 3) of 0.32 μM. Practical utility was demonstrated by accurate quantification of fluoride in Nile River water and human saliva samples. This dual nanoprobe strategy offers a rapid and cost-effective platform for fluoride analysis in support of healthcare and environmental monitoring applications.

Structural study of two polymer chains of poly(2-methoxyethyl glycidyl ether)-b-poly(2-ethoxyethyl glycidyl ether) thermoresponsive block copolymers using molecular dynamics simulations

Block copolymers are expected to be applied in a wide variety of fields due to the property of self-assembly. Our group has reported that poly(glycidyl ether) block copolymers exhibited complex temperature response in aqueous solution. In this study, we investigated the two chains of the block copolymer structure and configurations at different temperatures by using MD simulation. The results showed that at low temperatures, the polymer structure is linear and can form micelles, but above a certain temperature, the polymer structure changes to a U-shape and the micelle structure would be destroyed, which is responsible for the complex temperature response.