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Metal-Phenolic Coordination mediated Nanoemulsions for All-in-One Drug Delivery
No full textCombination chemotherapy is a promising strategy for cancer treatment, enhancing antitumor efficacy while minimizing drug resistance and mitigating the risk of single-drug overdose toxicity. Polymeric drug delivery carriers for combination chemotherapy have been developed; however, the synthetic process of amphiphilic polymers is time-consuming and laborious. The polymer entanglement-based drug encapsulation has been limited in achieving a high multidrug encapsulation efficiency because of the intrinsic preference for encapsulation of drugs upon their polarity. Herein, inspired by dynamic bonding and supramolecular assembly of metal-phenolic coordinate bonds at the oil/water interface, nanoemulsions were fabricated via a dropwise emulsion process. The emulsion interface was formulated by the coordinate bonds and created a colloidally stable emulsion with 50-100 nm in diameter for 3 weeks. These nanoemulsions enabled the coencapsulation of anticancer drugs, hydrophilic gemcitabine, and hydrophobic paclitaxel. Moreover, the treatment of dual-drug-encapsulated nanoemulsions reduced cellular viability (57.0 ± 0.0%) compared to that of gemcitabine only encapsulated (84.0 ± 9.9%) and paclitaxel only encapsulated (83.4 ± 7.2%) nanoemulsion treatment, demonstrating the potential of multidrug delivery carriers for synergistic combination therapy. © 2025 American Chemical Society.FALSEscopu
A novel soil moisture evaluation framework incorporating brightness temperature and a high-resolution 1 km summer brightness temperature dataset
No full textAccurate estimation of soil moisture (SM) is essential for various hydrological, meteorological, agricultural, and ecological applications. However, evaluating SM on a global scale remains challenging due to the limited availability of in-situ observations and the spatial heterogeneity of SM. Coarser resolution SM products, although beneficial for broader area coverage, often struggle to capture fine-scale variations influenced by local hydrological processes, land use, vegetation cover, and microclimates. To address these challenges, this study presents two contributions: a new 1 km brightness temperature (TB) dataset for the summer season and a two-step SM evaluation method. The 1 km TB dataset, developed by integrating SMAP’s 9 km SM product with radiative transfer modeling (RTM) and Mironov model, provides enhanced spatial resolution and is focused on areas where vegetation water content (VWC) is below 3 kg/m2, allowing for a more detailed analysis of SM variations. When validated against SMAP TB data, this dataset showed a solid correlation (R2 = 0.921) and a low root mean square error (RMSE = 4.254 K), making it a useful resource for fine-scale SM monitoring. The two-step evaluation method, which combines physical modeling (RTM and additional models) with machine learning techniques such as non-linear regression and convolutional neural networks (CNN), offers improvements in both temporal and spatial coverage. By transitioning from point-based validation using ISMN to an area-based approach, this method produces SM estimates at the same scale as the evaluated data, addressing the limitations of previous point-scale validations. Comparisons with ISMN data demonstrated the method’s robustness, with key metrics showing improved performance (R2 = 0.749, RMSE = 0.0561 m3/m3) across diverse environmental conditions. Furthermore, the evaluation of the ERA5 dataset using this method revealed a general overestimation of SM, particularly in tropical regions with dense vegetation. These findings are consistent with known ERA5 biases, reinforcing the reliability of the two-step method for global-scale SM evaluations. The results suggest that this approach, which integrates both physical models and machine learning, offers a more comprehensive and reliable framework for SM product evaluation, while the 1 km TB dataset provides valuable support for applications requiring finer spatial resolution. © 2025 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.TRUEsciescopu
Degradation Analysis and Design Strategies for Ion-Exchange Membrane-Based Aqueous Flow Batteries to Enhance Cyclability in Large-Scale Energy Storage Systems
No full textAqueous flow batteries generate or store energy by the directional flow of ions through an ion exchange membrane (IEM). In particular, due to the less safety concern and low rare-metal dependence, bipolar membrane acid-base flow battery (B-ABFB) has great potential for the next-generation energy storage system. B-ABFB constructs with a cation exchange membrane (CEM), anion exchange membrane (AEM), and bipolar membrane (BPM) which is fabricated by attaching the CEM and AEM. In the BPM, discharge and charge reactions can be conducted by neutralization of acid/base (H+ + OH− → H2O, discharge) and dissociation of water (H2O → H+ + OH− , charge), respectively. Despite these advantages, previously reported B-ABFBs have poor energy efficiency and cycle durability. The reason for poor performance is undesirable ion leakage, which inevitably occurs because the ion selectivity of IEMs is not ideal. In this study, I will investigate the degradation mechanism of B-ABFB caused by ion leakage and propose strategies to address the problems. In detail, based on the degradation mechanism, strategies to decrease the leakage of co-ions and the permeation of counter-ions will be suggested by designing the electrochemical system which includes the arrangement of ion exchange membranes.MasterI. Introduction 1
II. Experimental details 4
2.1 Preparation and Analysis of Electrolytes 4
2.2 Membrane cross-section and surface characterization 4
2.3 Residual Characterization of Ion-Exchange Membranes 5
III. Results and Discussion 6
3.1 Analysis of factors contributing to system degradation 6
3.1.1 Degradation factor 1: Permanent membrane fouling 6
3.1.2 To Quantify fouling agent 10
3.1.3 Degradation factor 2: Acid-base concentration decrease 12
3.1.4 Degradation factor 3: Redox concentration decrease due to Fe permeation 13
3.2 Rational design of B-ABFB to achieve the high performance 16
3.2.1 Prevention of permanent membrane fouling 18
3.2.2 Deceleration in Acid-Base Concentration Reduction 20
3.2.3 Deceleration in Redox Concentration Reduction 22
3.2.4 Systematic Performance Comparison: CEM-ended vs. AEM-ended Systems 24
IV. Conculsion 26
V. Reference 27
VI. Acknowledgement 2
Aggregation-Induced Excimer Emission-Controlled Ratiometric Fluorescence Assay for Determining Critical Micelle Concentration of Surfactants
No full textThe critical micelle concentration (CMC) is a key physicochemical parameter that defines the onset of micelle formation in surfactant solutions. The determination of the CMC is essential for understanding surfactant behavior in various chemical, biological, and industrial applications. This study introduces a ratiometric fluorescence assay that exploits the distinct monomer–excimer emission behavior of pyrene-butyldipicolylamine (Py-DPA) to determine the CMC of various surfactants. Py-DPA forms self-assembled nanoaggregates in a buffered solution and exhibits strong aggregation-induced excimer emission. As the concentration of surfactant increases and micelle formation occurs, the dissolution of Py-DPA nanoaggregates induces a distinct fluorescence transition from excimer to monomer emission, providing a reliable indicator of micellization. The ratiometric fluorescence changes in excimer–monomer emission of Py-DPA enable the determination of the CMC for various surfactants, including cationic, anionic, nonionic, and zwitterionic types, demonstrating the versatility and applicability of the assay. Furthermore, the robustness and applicability of the assay are demonstrated under various conditions including variations in pH, ionic strength, and temperature. © 2025 The Authors. Published by American Chemical SocietyTRUEsciescopu
Determination of topological charge of the vector vortex beams using polarization speckle size
No full textThe topological charge of vector vortex beams was determined by analyzing the polarization speckle size through the two-dimensional auto-correlation function of the scattered light. A non-separable vector beam, exhibiting singularities in both orbital angular momentum (OAM) and polarization, was also generated. The degree of polarization (DOP), obtained through the Stokes parameters, was used to verify the non-separability. These vector vortex beams show great potential for applications such as free-space optical communication and high-precision angular sensing
Qualitative analysis of edible oil mixture for omega-3 content using terahertz time-domain spectroscopy
No full textThe utility of terahertz time-domain spectroscopy (THz-TDS) for the qualitative and quantitative analysis of edible oils remains underexplored. Therefore, we aimed to characterize an edible oil mixture consisting of perilla, soybean, and corn oils using THz-TDS spectroscopy and compare the findings with those from Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. THz-TDS was used to obtain complex optical constants such as power absorption and refractive index of oils in the range of 0.2-2.0 THz. Perilla oil mixtures were quantitatively analyzed using complex dielectric constants in the THz frequency region. We characterized the double bond structure of omega-3 in perilla oil using THz-TDS. Furthermore, we used reflection-mode THz-TDS imaging to demonstrate its application as a non-destructive authenticity test for bottled edible oil.TRUEsciescopu
Advancements in thermoelectric materials: Emerging trends in organic, inorganic systems, and material informatics
No full textThermoelectric (TE) materials, which convert waste heat into electricity, have garnered significant attention due to the growing demand for sustainable energy solutions. This review comprehensively examines the fundamental principles, challenges, and advancements in TE materials. It emphasizes the approaches and materials employed to enhance TE properties, including electrical conductivity, thermal conductivity, and Seebeck coefficient, for achieving superior TE efficiency (ZT). The advances in inorganic, organic, and hybrid TE systems are explored and examined in detail. Inorganic materials like tellurides, sulphides, selenides, and oxides are reviewed for their exceptional TE performance over a wide range of temperatures. Conversely, organic materials such as polyaniline (PANI), Poly (3, 4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS), and poly (3-hexylthiophene) (P3HT) are emphasized for potential use in wearable electronics. Moreover, the integration of machine learning (ML) into TE material research is accelerating the discovery and optimization of high-ZT materials by predicting optimal compositions. This review also provides valuable insights into the latest advancements and highlights the role of ML in driving the future of TE systems, including applications in wearable electronics, industrial waste heat recovery, and sustainable energy generation.FALSEsciescopu
Geochemical distribution of heavy metals and implications for human health in floodplain area along Mekong River, Lao PDR
No full textArsenic and heavy metal accumulation in the environment have significant impacts on human health. With economic development and population growth, there is an increasing discharge of pollutants into the environment, particularly in floodplain areas, which makes them more vulnerable and dangerous. Despite these risks, there is a lack of research on the geochemical characteristics and the distribution of heavy metals that pose a threat to the health of Lao citizens. Therefore, this study aims to investigate the physicochemical characteristics and distribution of heavy metal contamination associated with the geographical differences in the floodplain areas along the Mekong River, as well as to identify the hydrogeochemical facies and mechanisms controlling the distribution of dissolved ions in groundwater. In addition, the potential human health risks associated with exposure to the heavy metals contaminated in food chains through various pathways (i.e., oral ingestion and dermal contact) of residents living in the study area of Champasak (CH) and Attapeu (AT) provinces were investigated. In order to investigate the physicochemical characteristics of groundwater, along with the distribution of heavy metals in groundwater, surface water, and soil in floodplain areas along the Mekong River and its tributaries in the Lao People's Democratic Republic (Lao PDR), a total of 152 groundwater samples were obtained from Champasak (n = 60) and Attapeu (n = 92) provinces, along with 18 surface waters and 40 topsoil samples. The results showed that groundwater is under oxidizing conditions, with pH ranging from 4.03 to 8.00, while surface water varied from 6.22 to 8.08. Calcium (Ca2+) and bicarbonate (HCO3 -) were the major cations and anions, respectively. The nitrate (NO3 -) concentration was significantly high in AT groundwater. Significantly poor water quality was observed, with high electrical conductivity (EC), arsenic (As), iron (Fe), and manganese (Mn) concentrations exceeding national (Lao) and international (WHO) permissible limits, especially in the AT study area. In contrast, soil in the CH area was found to be more contaminated with As, Cr, and Cu, with hotspot areas observed in soil formed from granite bedrock, indicating geographical differences resulting in distinctions between the quality of the two regions according to pollution index assessment. This preliminary work can be applied as important information for policy and regional environmental management, especially in floodplain areas in the Lao PDR. The mechanisms controlling the enrichment and mobility of major ions, arsenic (As), and barium (Ba) in groundwater in the floodplain regions along the Mekong River in Lao PDR have not yet been fully explained. Therefore, the investigation of the occurrence and spatial distribution of these dissolved ions in the two floodplain areas is needed. Graphical techniques (i.e., Piper plot, Gibbs diagram, and ionic ratio), statistical analysis (i.e., correlation analysis and principal component analysis (PCA)), and geochemical modeling (i.e., saturation index) were employed. The results suggested that Ca-HCO3 is the dominant water type in the study areas, with water- rock interaction being the main mechanism controlling the availability of major cations and anions in the groundwater, particularly the dissolution of carbonate minerals and cation exchange. Human activities, such as the application of chemical fertilizers, domestic sewage, and manure, influence nitrate (NO3 ⁻) concentrations. In the CH aquifer, the oxidation of sulfide minerals and the dissolution of evaporite minerals contribute to the mobility of arsenic (As), while the dissolution and precipitation processes of barium-bearing minerals (i.e., barite (BaSO4) and witherite (BaCO3)) control the presence of barium (Ba) in the region. In the AT aquifer, adsorption and desorption onto the solid phase of carbonate minerals, and the dissolution of witherite, primarily control the presence of As and Ba in the groundwater, respectively. To assess the demographical characteristics and the bioaccumulation of heavy metals in food chains leading to the human health risk in the floodplain areas, field questionnaires and environmental sample collection, along with the calculation of human health risk, were conducted. Among the 155 participants, approximately 23.9% had an elementary level of education, with farming being the main occupation and earning 20,000 kip per day on average. According to the groundwater usage behavior, most of the residents used their own private tube wells for various purposes, including drinking, bathing, washing, cooking, and irrigating. About 12.9% of the residents utilized groundwater as their main drinking water source, while 77.4% consumed bottled water. The areas that did not treat the groundwater before consumption experienced higher rates of waterborne diseases. The elevated levels of heavy metal contamination in groundwater, staple foods (rice grain), and vegetables (leafy and herb) posed potential non-carcinogenic and carcinogenic risks to the residents, especially through the ingestion pathway in the descending order of vegetables > rice grains > groundwater > soil.DoctorABSTRACT i
Contents iii
List of Tables vi
List of Figures. vii
CHAPTER 1 1
INTRODUCTION 1
1.1 Research motivation 2
1.2 Objectives 3
1.3 Outline of the thesis 4
CHAPTER 2 6
LITERATURE REVIEW 6
2.1 The definition of heavy metals. 7
2.1.1 Arsenic 7
2.1.2 Barium 8
2.1.3 Chromium 8
2.1.4 Copper 9
2.1.5 Iron 9
2.1.6 Manganese 10
2.1.7 Lead 11
2.1.8 Zinc 12
2.2 Definition of floodplain and heavy metal contamination in floodplain area 12
2.3 The distribution of heavy metal concentration in Mekong River Basin 14
2.4 The toxification of heavy metal on human health 15
2.5 Human health risk assessment 21
CHAPTER 3 23
ASSESSMENT OF PHYSICOCHEMICAL CHARACTERISTIC AND HEAVY METAL
DISTRIBUTION IN FLOODPLAIN AREA ALONG MEKONG RIVIER, LAO PDR 23
3.1 Introduction 24
3.2 Material and methods 25
3.2.1 Site description 25
3.2.2 Sample collection and preparation 27
3.2.3 Sample analysis 27
3.2.4 Pollution and ecological risk assessment 28
3.2.5 Data quality control and statistical analyses. 31
3.3 Result and discussion 32
3.3.1 Physicochemical characteristic of water in floodplain area along Mekong
River, Lao PDR 32
3.3.2 The distribution of heavy metals in the floodplain area 37
3.3.3 Pollution assessment 44
3.4 Conclusion 48
CHAPTER 4 49
THE SPATIAL DISTRIBUTION AND POTENTIAL SOURCES OF HEAVY METAL
CONTAMINATION IN THE FLOODPLAIN AREA 49
4.1 Introduction 50
4.2 Material and methods 51
4.2.1 Hydrogeochemical analysis method. 51
4.2.2 Geochemical modeling 52
4.2.3 Multivariate statistical analysis 52
4.3 Result and discussion 53
4.3.1 Hydrogeochemical evolution and mechanism controlling the major ion in
groundwater 53
4.3.2 Tracing major ion sources using ionic ratios 55
4.3.3 Potential sources of arsenic and barium in groundwater 60
4.4 Conclusion 71
CHAPTER 5 72
IMPLICATIONS OF HEAVY METAL ACCUMULATION IN FOOD CHAIN FOR HUMAN
HEALTH 72
5.1 Introduction 73
5.2 Material and methods 74
5.2.1 Field sample collection, preparation, and analysis 74
5.2.2 Field data collection of demographic and health information 76
5.2.3 Human health risk assessment 77
5.2.4 Data quality control and statistical analyses. 81
5.3 Result and discussion 82
5.3.1 Heavy metal concentration in food crops 82
5.3.2 The demographic and health data 85
5.3.3 Health risk assessment 92
5.4 Conclusion 108
CHAPTER 6 109
CONCLUSIONS AND RECOMMENDATION 109
6.1 Conclusions 110
6.2 Recommendation 111
REFERENCES 112
APPENDIX 127
ACKNOWLEDGMENT 132
CURRICULUM VITAE 13
Obstacle Avoidance of a UAV Using Fast Monocular Depth Estimation for a Wide Stereo Camera
Full text linkIn this study, we designed an obstacle avoidance algorithm for a quadrotor unmanned aerial vehicle (UAV) equipped with a wide field-of-view (FOV) stereo camera, utilizing a learning-based depth estimation approach. Depth estimation using monocular cameras is gaining interest as a viable alternative to large and heavy sensors, such as light detection and ranging (LiDAR) sensors. However, deep learning-based depth estimation has low accuracy unless the depth estimation is done in an environment similar to that of the training data. Therefore, we first designed a depth estimation network for a wide-FOV stereo camera using two cameras. Then, we estimated the depth image using a convolutional neural network and improved the accuracy using stereo matching. We used the estimated depth images to develop a simple behavior-arbitration-based control algorithm that steers the quadrotor away from 3-D obstacles. We conducted simulations and experiments using a real drone in an indoor and outdoor environment to validate our proposed algorithm. An analysis of the experimental results showed that the proposed method could be employed for navigation in cluttered environments.TRUEsciescopu
