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Multifunctional Iron–Silver (Fe–Ag) Nanocomposites for Combined Anticancer Therapies: A Pathway to Enhanced Treatment Outcomes
No full textThe advancement of cancer treatment has been significantly influenced by the exploration of nanoparticles, which promise to enhance traditional therapeutic approaches. This review focuses on iron–silver (Fe–Ag) nanocomposites, which have emerged as a versatile tool in anticancer therapy due to their unique multifunctional properties. Fe–Ag nanocomposites combine the magnetic properties of iron with the anticancer attributes of silver, allowing for precise targeting, localized treatment, and enhanced therapeutic efficacy. The magnetic properties of iron facilitate targeted drug delivery and magnetic hyperthermia, while silver contributes to anticancer effects through its well-established biological activity. This review examines the synthesis, characterization, and applications of Fe–Ag nanocomposites in cancer therapy, including their role in enhancing heating efficiency through magnetic hyperthermia and photothermal therapy. It also discusses the challenges and opportunities associated with translating these nanocomposites from laboratory research to clinical applications, highlighting the need for comprehensive preclinical studies, standardized production protocols, and regulatory approvals
Carbon cycling across ecosystem succession in a north temperate forest: Controls and management implications
No full textDespite decades of progress, much remains unknown about successional trajectories of carbon (C) cycling in north temperate forests. Drivers and mechanisms of these changes, including the role of different types of disturbances, are particularly elusive. To address this gap, we synthesized decades of data from experimental chronosequences and long-term monitoring at a well-studied, regionally representative field site in northern Michigan, USA. Our study provides a comprehensive assessment of changes in above- and belowground ecosystem components over two centuries of succession, links temporal dynamics in C pools and fluxes with underlying drivers, and offers several conceptual insights to the field of forest ecology. Our first advance shows how temporal dynamics in some ecosystem components are consistent across severe disturbances that reset succession and partial disturbances that slightly modify it: both of these disturbance types increase soil N availability, alter fungal community composition, and alter growth and competitive interactions between short-lived pioneer and longer-lived tree taxa. These changes in turn affect soil C stocks, respiratory emissions, and other belowground processes. Second, we show that some other ecosystem components have effects on C cycling that are not consistent over the course of succession. For example, canopy structure does not influence C uptake early in succession but becomes important as stands develop, and the importance of individual structural properties changes over the course of two centuries of stand development. Third, we show that in recent decades, climate change is masking or overriding the influence of community composition on C uptake, while respiratory emissions are sensitive to both climatic and compositional change. In synthesis, we emphasize that time is not a driver of C cycling; it is a dimension within which ecosystem drivers such as canopy structure, tree and microbial community composition change. Changes in those drivers, not in forest age, are what control forest C trajectories, and those changes can happen quickly or slowly, through natural processes or deliberate intervention. Stemming from this view and a whole-ecosystem perspective on forest succession, we offer management applications from this work and assess its broader relevance to understanding long-term change in other north temperate forest ecosystems
Multidecadal patterns of coastal profile change reveal low likelihood of beach recovery following a period of high Lake Michigan water level
No full textCoastal erosion is a hazard for sandy beaches along the Great Lakes of North America, especially during periods of high lake level. A barrier to managing these hazards is the lack of a process-based understanding of nearshore sediment transport and geomorphic connectivity. In this study, a multidecadal dataset of beach and nearshore profiles collected at six sandy beaches along the eastern coast of Lake Michigan and contemporaneous hydrodynamic data are utilized to quantify long-term boundaries of sediment transport during accretionary and erosive conditions. Our results indicate that at most sites longshore sediment transport is the dominant force shaping multidecadal profile evolution. Accretionary wave conditions can generally only transport sediment onshore from shallow sediment ridges of the inner nearshore and from the lower reaches of the subaerial beach in longshore drift. In contrast, erosive wave conditions can mobilize sediment from all areas of the profile and transport it offshore. Sediments stored in deeper nearshore bars can be activated by high-energy erosive wave conditions, but these features likely primarily function as multidecadal sinks for eroded beach sediment given the dominance of offshore-directed transport for these wave conditions. Furthermore, these results suggest that the likelihood of recovery following high lake level should decrease in this region as extensive coastal armoring reduces sediment availability and increases reflective wave energy in the accretionary wave-accessible portions of the nearshore. Ultimately, this study puts forth a simple method for predicting the likelihood of future beach recovery that can be used to help guide coastal management
Activation of toll-like receptor 2 promotes the expression of inflammatory mediators and cell proliferation of human polycystic kidney disease cells
Get PDFAutosomal dominant polycystic kidney disease (ADPKD) is characterized by the progressive enlargement of fluid-filled cysts, leading to a decline in renal function. Toll-like receptors (TLR)-2 and TLR4 are pattern recognition receptors and components of the innate immune response. We found that mRNA levels for TLR2 and TLR4, an adaptor protein MyD88, and the transcription factor NF-κB were elevated in the kidneys of ADPKD patients and PKD mice. There was decreased expression of IκBα, an inhibitory protein sequestering NF-κB in the cytosol, and increased NF-κB nuclear translocation in human ADPKD kidneys compared with normal human kidneys (NHK). Pam3CSK4, a synthetic TLR2 agonist, increased the phosphorylation of IκBα, decreased its total levels, and caused NF-κB nuclear translocation and upregulation of pro-inflammatory mediators in cultured human ADPKD cells. Pam3CSK4 also increased phosphorylated ERK, a mitogen-activated protein kinase, and phosphorylated S6, a downstream target of the mTOR pathway, and accelerated ADPKD cell proliferation. By contrast, Pam3CSK4 did not affect NF-κB or ERK in NHK cells, but rather induced cytotoxicity, suggesting that TLR2 activation\u27s effect was specific to ADPKD cells. Treatment with a TLR4 agonist did not affect NF-κB or ERK signaling in either ADPKD or NHK cells. Inhibition of TGF-β-activated kinase-1 (TAK1) effectively suppressed Pam3CSK4-induced NF-κB and ERK activation and the proliferation of ADPKD cells. These findings suggest that activation of TLR2 increases NF-κB-mediated-inflammatory mediators and ERK-dependent cell proliferation through TAK1 in ADPKD cells. We propose that the TLR2/TAK1 axis is a potential therapeutic target to reduce inflammation and cyst growth in ADPKD
High-order bound-preserving finite difference methods for incompressible two-phase flow in porous media
No full textIn this paper, we develop high-order bound-preserving (BP) finite difference (FD) methods for solving the incompressible and immiscible two-phase flow problem with capillary pressure in porous media. We use the implicit pressure explicit saturation (IMPES) scheme to solve for the pressure, auxiliary variables, and saturations of each phase in the coupled system. The boundedness of the saturations of the two phases, Sw and Sn, between 0 and 1 is an important physical characteristic. Applying non-physical numerical approximations may lead to significant oscillations in the numerical results and cause instability in the simulation. We apply high-order FD method and BP technique to maintain the high-order accuracy and the boundary of saturations. In the BP technique, the main idea is to choose an appropriate time step and apply positivity-preserving (PP) technique to Sw and Sn, respectively, and ensure that Sw+Sn=1. In addition, the high-order accuracy is obtained by the parameterized flux limiter. Numerical examples are presented to demonstrate the high-order accuracy of the scheme and the effectiveness of the BP technique
How electricity utility practitioners in the United States approach power system resilience
Get PDFThis study explores the understanding and practice of resilience among electrical utilities in the United States, focusing on how practitioners in the utility sector conceptualize and apply resilience in their work. As electricity becomes increasingly central to modern life, powering critical infrastructure and essential services, the resilience of power systems has gained prominence in energy policy and planning. However, there is a lack of standardized definitions and approaches to resilience in both academia and practice, particularly from an energy service perspective. The research employs a qualitative approach, utilizing semi-structured interviews with experts (practitioners) from transmission and distribution utilities in the United States to examine their definitions, understanding, and applications of resilience. By adopting a grounded approach, the study aims to identify key themes and concepts that practitioners associate with power system resilience. The findings outline that there is no clear definition of resilience amongst utility practitioners, and resilience and reliability are often used interchangeably/synonymously as there are no fixed indicators for resilience amongst practitioners. At present, unlike reliability, utilities are not including resilience as a term in their long-term resource planning, and neither are reporting resilience-based indicators to any of the government agencies. The findings contribute to the ongoing dialogue on energy resilience and offer a foundation for developing more comprehensive and context-specific approaches to building resilient energy systems that prioritize critical services and vulnerable populations
Optimizing Epoxy Nanocomposites with Oxidized Graphene Quantum Dots for Superior Mechanical Performance: A Molecular Dynamics Approach
Get PDFDue to their excellent mechanical properties, epoxy composites are widely used in low-density applications. However, the brittle epoxy matrix often serves as the principal failure point. Matrix enhancements can be achieved by optimizing polymer combinations to maximize intermolecular interactions or by introducing fillers. While nanofillers such as clay, rubber, carbon nanotubes, and nanoplatelets enhance mechanical properties, they can lead to issues like agglomeration, voids, and poor load transfer. Quantum dots, being the smallest nanofillers, offer higher dispersion and the potential to promote intermolecular interactions, enhancing stiffness, strength, and toughness simultaneously. This study employed molecular dynamics simulations to design graphene quantum dot (GQD) reinforced epoxy nanocomposites. By functionalizing GQDs with oxygen-based groups─hydroxyl, epoxide, carboxyl, and mixed chemistries─their effects on the mechanical properties of nanocomposites were systematically evaluated. Results show that hydroxyl-functionalized GQDs provide optimal performance, increasing stiffness and yield strength by 18.4 and 56.1%, respectively. Structural analysis reveals that these GQDs promote a closely packed molecular configuration, resulting in reduced free volume
Mapping Peatland Distribution and Quantifying Peatland Below-Ground Carbon Stocks in Colombia\u27s Eastern Lowlands
Get PDFThe extent and distribution of tropical peatlands, and their importance as a vulnerable carbon (C) store, remain poorly quantified. Although large peatland complexes in Peru, the Congo basin, and Southeast Asia have been mapped in detail, information on many other tropical areas is uncertain. In the Eastern Colombian lowlands, peatland area estimates range from 700 km2 to nearly 60,000 km2, leading to highly uncertain C stocks. Using new field data, high-resolution Earth observation (EO), and a random forest approach, we mapped peatlands across Colombian territory East of the Andes below 400 m elevation. We estimated peatland extent using two approaches: a conservative method focused on medium-to-high peat probability areas and a more inclusive one accounting for large low-probability areas. Multiplying these extents by below-ground carbon density yields a conservative estimate of 0.95 (0.6–1.39 Pg C, 95% confidence interval) over 9,391 km2 (7,369–11,549 km2) and up to 2.86 Pg C (1.76–4.22 Pg C) across 29,069 km2 (22,429–36,238 km2). Among four potentially peat-forming ecosystems identified, palm swamps and floodplain forests contributed most to the peat extent and C stock. We found that most peatland patches were relatively small, covering less than 100 ha. We compared our map to previously published global and pan-tropical peat maps and found low spatial overlap among them, suggesting that peat maps uninformed by local field information may not precisely specify which landscape areas within a peatland-rich region are actually peatlands. We further assessed the suitability of different EO and climate variables, highlighting the need for high-resolution data to capture local heterogeneities in the landscape
ThermalTrack Dataset- Training Images- Fused RGB LWIR- sequence 9
Get PDFWe present a wheel track detection system that leverages RGB- Thermal (RGB-T) imaging, where thermal channels reveal critical temperature differentials between compacted tracks and loose snow- tracks exhibit higher thermal inertia and lower reflectivity, emitting stronger radiation signatures even in visually homogeneous conditions. By fusing these distinctive thermal patterns with RGB spatial information, our method reliably identifies navigable tracks, enabling robust path-following in complete white-out conditions where snow textures and terrain features become indistinguishable
Linear response of driven non-Hermitian photonic systems
Get PDFThe notion of non-Hermitian engineering in optics and photonics has attracted considerable attention in the past decade. From laser devices and sensing applications to light trapping and guiding, non-Hermitian engineering provides additional degrees of freedom that allows for more control over light-matter interaction. It is thus of great importance to develop a deep insight into the linear response of non-Hermitian optical systems. We begin by studying the linear response of non-Hermitian Hamiltonian systems under general conditions and derive an expression for its Green\u27s operator in terms of its eigenvectors and its canonical Jordan vectors. Next, we investigate the quantum noise in optical amplifiers operating at non-Hermitian singularities known as exceptional points. We then examine the response of non-Hermitian systems under time-varying, non-harmonic input signals. Finally, we reveal that one of the most important tools used to analyze non-Hermitian optical systems, namely temporal coupled-mode theory, can break down under peculiar input conditions. This work provides a deeper understanding and a fresh look on the behavior and response of driven non-Hermitian photonic systems and may play an important role in designing and building next-generation non-Hermitian optical devices