Search Results (1,640)

This study examines the interfacial and structural evolution of titanium disulfide (TiS₂) during Ca²⁺ intercalation/deintercalation in concentrated aqueous CaCl₂. Electrochemical measurements were combined with ex situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy to characterize the solvation structure, potential window, and reversibility in concentrated CaCl₂ electrolytes. Increasing the CaCl₂ concentration from 1.0 to 8.0 M was accompanied by reduced gas evolution and an expanded practical operating window. Stepwise analysis identified the potential range −1.00 to 0.10 V (vs. the saturated calomel electrode) as a practical window that minimized TiO₂/S₈ formation while preserving reversible Ca²⁺ intercalation. Ex situ XRD showed reversible (001) shifts, consistent with interlayer expansion and contraction, and peak broadening was indicative of partial amorphization and defects. XPS revealed CaS and polysulfides (S_z²⁻, 2 ≤ z ≤ 8) to be the prevalent surface species with limited Ca(OH)₂ and CaSO₄; within the detection limits, no chlorine-containing reduction products were observed after charging. The electrochemical and spectroscopic results indicate that intercalation is accompanied by partial sulfur-centered reduction and defect signatures, with associated changes in the interfacial charge-transfer characteristics and reversibility. These findings link the potential, interfacial chemistry, and lattice response, and suggest design considerations for stable aqueous multivalent-ion storage. Full article

Traditional drug delivery methods for gastrointestinal diseases, including oral and systemic administration, often suffer from degradation, inadequate mucosal absorption, and off-target toxicity. Consequently, these methods result in low bioavailability and suboptimal therapeutic outcomes for localized conditions such as inflammation and early-stage cancer. This review examines the innovative integration of advanced bioengineering platforms with therapeutic gastrointestinal endoscopy to address these delivery challenges. We concentrate on three principal bioengineered platforms: (1) nanoparticle systems (e.g., lipid, polymeric, and inorganic nanoparticles) designed for localized chemotherapy and theranostics; (2) in situ-forming hydrogels that serve as intelligent wound management materials and sustained drug depots; and (3) drug-eluting and biodegradable stents that convert passive luminal scaffolds into active, long-term drug-releasing devices. An analysis of these platforms demonstrates that their synergy with endoscopy facilitates precise, minimally invasive, and sustained local therapy, potentially transforming the treatment landscape for gastrointestinal diseases such as cancer and inflammatory bowel disease. Additionally, we investigate advanced strategies, including active targeting and stimulus-responsive release mechanisms, to enhance spatial precision. Despite promising preclinical advancements, clinical translation encounters challenges related to long-term biocompatibility, scalable manufacturing, regulatory pathways for drug-device combinations, and cost-effectiveness. Ultimately, the convergence of bioengineering and endoscopy presents significant potential to usher in a new era of precise, localized, and sustained micro-invasive treatments in gastroenterology. Full article

Porous Ti-6Al-4V foams are excellent materials due to their low density, high specific strength, and excellent biocompatibility. This study investigates the fabrication of open-cell Ti-6Al-4V foams using the replica impregnation method with polyurethane templates of varying pore sizes (20, 25, and 30 ppi) and sintering temperatures (1170 °C, 1200 °C, 1250 °C, and 1280 °C). The effects of these parameters on microstructural evolution, phase composition, and mechanical properties were examined. Microstructural analysis showed that optimum densification occurred at 1250 °C. However, at 1280 °C, excessive grain growth and pore coarsening were observed. XRD, SEM, and EDS analyses confirmed that α-Ti was the matrix phase, while titanium carbide formed in situ as a result of the carbon residues released from the decomposed polyurethane template. With the development of the TiC phase and enhanced interparticle bonding due to sintering, the compressive strength progressively increased up to 1250 °C. At 1280 °C, strength decreased due to excessive TiC growth, causing brittleness and pore coarsening, reducing structural integrity. Maximum compressive strength of 40.2 MPa and elastic modulus of 858.9 MPa were achieved at 1250 °C with balanced TiC dispersion and pore structure. Max density of 1.234 g/cm³ was obtained at 1250 °C. Gibson-Ashby analysis and the fracture surfaces confirmed the brittle behavior of the foams, which is attributed to the presence of TiC particles and microcracks in the structure. The study concludes that 1250 °C provides an ideal balance between densification and structural integrity, offering valuable insights for biomedical and structural applications. Full article

Vibrational spectroscopy is one of the most powerful techniques available for the characterization of materials for Li-ion batteries (LIBs) and one of the most useful tools when X-ray diffraction is ineffective for amorphous substances. Raman spectroscopy is essentially a probe to examine the surface of compounds that strongly absorb visible light, which is the case for all electrode materials, while infrared spectroscopy is a tool that examines the entire volume of particles. The purpose of this review is to study the lattice dynamics of cathode, anode, and electrolyte materials of advanced LIBs, especially nanomaterials for high-power-density application. Ex situ and in situ analyses are presented, which satisfy several key issues, such as structural stability over long-term cycling. Full article

Human–autonomy teams (HATs) incorporating uncrewed aerial systems (UASs) play critical roles in a variety of safety-critical systems. Increased autonomy in HATs in beyond visual line of sight (BVLOS) UAS operations introduces new mission, safety, and logistics system performance challenges, and highlights the scarcity of in situ empirical research examining UAS and operator performance and operator situation awareness in HATs with embedded autonomy, particularly in remote and infrastructure-poor settings. This work addresses this research gap and examines the challenges and contributions of HATs employing various levels of autonomy in remote humanitarian logistics delivery systems, using initial empirical data from an on-going study in a resource-constrained environment. The preliminary results suggest the importance of considering human and technology performance and perceptions in HATs together, particularly in infrastructure-poor settings such as the Arctic, where leveraging limited resources is critical and the force multiplication effects of HATs may have significant impact. Full article

Microbial colonization of heritage materials is a well-known conservation issue. When necessary, it is removed using mechanical, physical, or chemical methods, with biocide formulations being a common choice. The need to reduce dependence on conventional biocides has led to the exploration of innovative alternative methods and new formulations with biocidal properties for the conservation of heritage objects. Alternative approaches include natural compounds such as plants’ essential oils. While these natural options show promise, they present challenges—such as inconsistent effectiveness, possible toxicity, and the need for thorough compatibility testing with historic materials. Therefore, although some concerns are legitimate, the “run” to alternative substances is a growing concern as well. A comprehensive selection and examination of international research articles from the past two decades on this subject has been conducted. The detailed and critical analysis of existing data on essential oils, hydrolates, and other plant-derived extracts studied to prevent and/or eradicate the colonization of microbial communities on heritage objects focused on the effect on microorganisms in controlled environments, in situ applications on microorganisms, encapsulation in hydrogels and emulsions, toxicity and ecological impact, and alterations of heritage materials. The review also discusses the advantages, limitations, and practical implications of these strategies. Full article

Background/Objectives: Segmental non-mass enhancement (NME) is the breast MRI distribution pattern with the highest positive predictive value (PPV) for malignancy. Despite its diagnostic relevance, its imaging characteristics have rarely been examined in isolation, leaving uncertainty in clinical practice. This multicenter retrospective cohort study aimed to evaluate multiparametric MRI features—including internal enhancement pattern, dynamic contrast-enhanced (DCE) kinetics, and diffusion restriction—in segmental NME to identify malignancy predictors. Methods: This retrospective cohort review included 14,834 breast MRI reports from five institutions (September 2017–February 2024), identifying 103 women (mean age, 44.4 ± 9.9 years) with segmental NME (70 malignant, 33 benign). MRI was performed at 1.5 T or 3 T using standardized protocols. Two breast radiologists, blinded to pathology, assessed internal enhancement, DCE kinetics, diffusion restriction, and short tau inversion recovery (STIR) features according to BI-RADS. Statistical analyses included chi-square/Fisher’s tests and logistic regression. Results: Clustered ring enhancement (CRE) was significantly associated with malignancy (p = 0.004). Fast initial-phase enhancement (p < 0.001) and delayed-phase washout (p = 0.011) also correlated with malignancy. On multivariate analysis, fast initial-phase enhancement remained an independent predictor (odds ratio [OR] = 5.133, p = 0.031), whereas slow enhancement predicted benignity (OR = 0.194, p = 0.020). Histologies included ductal carcinoma in situ, invasive ductal carcinoma, granulomatous mastitis, and benign hyperplastic lesions. Conclusions: This study, focusing exclusively on segmental NME, identifies CRE, fast initial-phase enhancement, and washout kinetics as reliable imaging biomarkers. Incorporating these features into breast MRI interpretation may improve diagnostic accuracy, risk stratification, and management decisions. Full article

Background/Objectives: Diode lasers are used as adjuncts for endodontic disinfection, but their depth-resolved effects on root dentin are insufficiently described. This ex vivo study used optical coherence tomography (OCT) to qualitatively document laser-related morphological signatures on canal walls. Methods: Palatal roots from extracted maxillary first molars were standardized and hemisectioned to create specimens allocated to a conventional diode-laser protocol, a higher-power protocol, or control. A 940-nm diode laser with endodontic tips was applied per group. Swept-source OCT acquired serial B-scans along the root length. Two endodontists reviewed images for thermally induced morphological alterations (TIMAs). Reporting is descriptive. Results: OCT revealed laser-related hyper-reflective linear/radial signatures extending from the canal lumen toward the external root surface in laser-treated specimens. Qualitatively, signatures appeared more conspicuous and extended deeper with the higher-power protocol than with the conventional protocol. Findings were most evident in the coronal/middle thirds. Control specimens served to contextualize background appearances from preparation and sectioning. Representative B-scans illustrate typical patterns. The novelty of the present study results from the identification of areas of morphological alteration through the OCT examination of the walls of the root canals. Conclusions: Depth-resolved OCT can visualize dentinal alterations associated with diode-laser irradiation in an ex vivo model. These observations support careful parameter selection and motivate in situ studies with concurrent temperature monitoring and histologic correlation. Full article

The pervasive contamination of water bodies by refractory organic pollutants necessitates the development of advanced purification technologies. Plasma has emerged as a promising solution, capable of generating a broad spectrum of reactive oxygen and nitrogen species (RONS), UV photons, and electrons in situ, thereby directly degrading contaminants. However, the practical application of plasma-alone systems is often constrained by limited energy efficiency and insufficient mineralization capacity. To overcome these challenges, the integration of plasma with homogeneous advanced oxidation processes (AOPs) has been established as a highly effective strategy. By coupling plasma with catalysts such as peroxymonosulfate (PMS), peracetic acid (PAA), periodate (PI), and Fenton reagents (Fe²⁺/Fe³⁺), a remarkable synergistic effect is achieved. This synergy arises from the multi-modal activation of catalysts by plasma via energetic electrons, UV photolysis, and radical-induced reactions, while the catalysts, in turn, consume long-lived plasma products and regulate reaction pathways. The resultant ‘plasma/catalytic’ system significantly enhances the degradation rate and mineralization efficiency of pollutants, broadens the operational pH window, and improves overall energy utilization. This review systematically examines the mechanisms, performance, and influencing factors of these hybrid systems, and discusses current challenges and future prospects to guide the development of this synergistic technology for sustainable water remediation. Full article

Bimetallic alloys are widely used as heterogeneous catalysts due to their unique physico-chemical properties for improving catalytic reactions. Typically, the structures of alloy catalysts are inherently dynamic under gas environments, which plays a crucial role in their catalytic activity, stability and selectivity. One method of enhancing the catalytic performance of bimetallic nanomaterials is, therefore, to tune or control the surface structure of the nanomaterials, and tremendous progress has been made in this area in the past decade. In this review, we primarily focus on the dynamic structure evolution of binary noble metal alloy catalysts influencing their catalytic performance during the thermal catalytic reaction. First, we summarize the advantage of binary noble metal alloy catalysts and their structure correlation with catalysis. Then, we examine how the structure of precious-metal-based alloy catalysts evolves in response to varying gas environments and the resulting structures impacts on heterogeneous catalytic activity. Further, the advanced characterizing techniques, i.e., in situ scanning/transmission electron microscopy (in situ S/TEM) and near-ambient pressure scanning tunneling microscopy (NAP-STM) are outlined for visualizing these structural evolutions. Finally, we summarize the remaining challenges and outlooks for the future in this research field and offer the potential direction of rational design catalysts with high energy-efficient and sustainable catalytic processes. Full article

Immune checkpoint inhibitors (ICIs), particularly PD-1/PD-L1 antibodies, have significantly improved outcomes in a variety of solid tumors, including urothelial carcinoma. However, their use is frequently associated with immune-related adverse events (irAEs) which frequently affect the skin and mucous membranes. Among these, plasma-cell-rich infiltrates are exceptionally rare. Circumorificial plasmacytosis (COP) is a rare, predominantly reactive condition typically involving mucosal transition zones, with histologic features characterized by dense, polyclonal plasma cell infiltrates and a benign clinical course. Only two case reports have described COP in association with ICI therapy and, to date, transformation or overlap with lymphoproliferative disorders such as marginal zone lymphoma has not been documented. We report the case of an 86-year-old male with urothelial carcinoma who developed a progressive, ulcerated, bleeding lesion of the lower lip during adjuvant nivolumab therapy. Histologic examination revealed a dense subepithelial infiltrate of mature plasma cells and lymphocytes. Direct and indirect immunofluorescence studies were negative, excluding autoimmune blistering disorders. Immunohistochemistry showed a predominance of CD138-positive plasma cells with a moderate kappa light-chain shift, CD19 expression, and absence of CD56, Cyclin-D1, and CD117, arguing against a plasma cell neoplasm. Molecular analysis via multiplex PCR revealed a clonal B-cell population with distinct IgH rearrangements, and some EBV-positive cells were also identified by EBER in situ hybridization. The histopathologic and molecular findings suggested a marginal zone lymphoma-like, plasmacytic proliferation arising in the setting of COP. This case illustrates a rare and diagnostically challenging constellation at the intersection of reactive and clonal B-cell proliferations in the context of ICI therapy. Although the lesion demonstrated features of clonality, the overall low B-cell content, indolent clinical course, and lack of systemic involvement support a reactive, immunodeficiency-associated lymphoproliferation rather than overt lymphoma. This case expands the known spectrum of mucocutaneous irAEs and highlights the need for careful clinicopathologic correlation, including immunophenotyping and molecular diagnostics. Awareness of such rare presentations is essential to avoid overdiagnosis and unnecessary systemic treatment in patients with otherwise indolent lesions. Full article

Nanomaterial-based systems (NBS) have emerged as transformative elements in advanced surface engineering, offering superior corrosion resistance, mechanical strength, and tribological resilience governed by unique phenomena inherent to the nanoscale. However, bridging the knowledge gap between these enhanced physicochemical properties and the metrological tools required to quantify them remains a critical challenge. This review provides a comprehensive examination of the fundamental mechanisms, state-of-the-art experimental techniques, and computational strategies employed to probe NBS behavior. The article first elucidates the core mechanisms driving performance, including passive barrier formation, stimuli-responsive active corrosion inhibition, grain boundary strengthening, and the formation of protective tribo-films by 2D nanomaterial-based systems. Subsequently, the article evaluates the transition from conventional macroscopic testing to high-resolution in situ characterization, highlighting the capabilities of High-Speed Atomic Force Microscopy (HS-AFM), Liquid Cell Transmission Electron Microscopy (LC-TEM), and nanoindentation in visualizing dynamic defect evolution and measuring localized mechanical responses. Furthermore, the indispensable role of computational materials science—specifically Molecular Dynamics (MD) and Machine Learning (ML)—in predictive modeling and elucidating atomic-scale interactions is discussed. Finally, persistent challenges regarding substrate interference, sample heterogeneity, and instrumentation limits are addressed, concluding with a perspective on future research directions focused on standardization, operando testing, and the development of AI-driven “Digital Twins” for accelerated testing and material optimization. Full article

Culinary culture shock (CCS)—the discomfort and ambivalence travelers feel when encountering unfamiliar foods—remains underexplored from a short-horizon, trip-bounded perspective. While prior work notes both attractions and impediments of food in tourism, a process-oriented account of how ordinary travelers experience and navigate CCS during brief trips is still limited. This study examines CCS in Guangzhou, China and delineates how it shapes travelers’ evaluations of place. We adopt a qualitative design, combining 30 semi-structured interviews with in situ ethnographic observations across markets, street-food settings, restaurants, and guided food tours, supplemented by document analysis (e.g., visitor materials and menus). Using reflexive thematic analysis, we identify three recurrent coping trajectories—avoidance, gradual adaptation, and immersion—that unfold nonlinearly as travelers recalibrate expectations, manage sensory dissonance, and renegotiate comfort boundaries. We integrate expectancy–disconfirmation theory (EDT) with an embodied view of tasting to develop the Palate Adaptation Spiral Model (PASM), which explains CCS as recursive cycles of appraisal, strategy enactment, and re-appraisal within the span of a trip. Social influence (peers, guides, and service staff) operates as a cross-cutting mechanism that can accelerate adaptation or entrench avoidance depending on cue valence and credibility. The study clarifies the scope of CCS as general travel encounters (not restricted to culinary-motivated tourists) and specifies contextual conditions under which negative reactions are reversible. Theoretically, we connect EDT to short-term culinary adaptation through PASM; practically, we outline design levers—pre-trip expectation management, pictorial/transparent menus, and guide-mediated tasting sequences—to reduce anxiety and support constructive exploration. Full article

Pax6 plays a highly conserved role in the formation of the eye, development, and patterning of the nervous system across bilaterians. Nevertheless, there are no studies focusing on the role of Pax6 during asexual reproduction, a developmental trajectory that is widespread among metazoans. The present study represents the first investigation of Pax6 gene expression during agametic propagation in annelids. We identified in the asexually reproducing annelid Nais communis four homologs of Pax6 and examined their developmental patterns by in situ hybridization. To establish a morphological basis for the expression patterns, we used immunohistochemistry and confocal laser scanning microscopy to describe the nervous system architecture of the growing adults and remodeling of the original ventral nerve cord, development of the new brain, ventral ganglia, peripheral nerves, and sensory organs in asexually reproducing worms. Our results support the hypothesis of an evolutionarily conserved function of Pax6 genes in the development of the eye and other sensory organs, as well as the central nervous system, among bilaterians, regardless of developmental trajectory. On the other hand, identified Pax6 homologs show differential expression within the developing new head and tail ends. Differences in spatiotemporal expression patterns may be evidence of functional diversification of duplicated homologs. Full article

Accurate equilibrium-line altitude (ELA) estimates are a valuable proxy for evaluating glacier mass balance conditions and interpreting climate-driven change in the Canadian high Arctic, where sustained in situ observations are limited. A scalable remote-sensing framework is evaluated to extract the snow cover ratio (SCR) and snowline altitude (SLA) on White Glacier (Axel Heiberg Island, Nunavut) and to assess the agreement with in situ ELA measurements. Ten-metre Sentinel-2 imagery (2019–2024) is processed with a hybrid pipeline comprising the principal component analysis (PCA) of four bands (B2, B3, B4, and B8), unsupervised K-means for pseudo-label generation, and a Random Forest (RF) classifier for snow/ice/ground mapping. SLA is defined based on the date of seasonal minimum SCR using (i) a snowline pixel elevation histogram (SPEH; mode) and (ii) elevation binning with SCR thresholds (0.5 and 0.8). Validation against field-derived ELAs (2019–2023) is performed; formal SLA precision from DEM and binning is quantified ($\pm 4.7$ m), and associations with positive degree days (PDDs) at Eureka are examined. The RF classifier reproduces the spectral clustering structure with >99.9% fidelity. Elevation binning at $\mathrm{SCR}\ge 0.8$ yields SLAs closely matching field ELAs (Pearson $r=0.994$, $p=0.0006$; RMSE $=30$ m), whereas SPEH and lower-threshold binning are less accurate. Interannual variability is pronounced as follows: minimum SCR spans 0.46–0.76 and co-varies with SLA; correlations with PDDs are positive but modest. Results indicate that high-threshold elevation-bin filtering with machine learning provides a reliable proxy for ELA in clean-ice settings, with potential transferability to other data-sparse Arctic sites, while underscoring the importance of image timing and mixed-pixel effects in residual SLA–ELA differences. Full article