Search Results (88)

This study examines interfacial intermetallic compound (IMC) growth in Pb-free/Pb mixed assemblies comprising 450 µm SAC305 solder balls and Cu pads printed with a 0.12 mm layer of Sn63Pb37 solder paste. Samples were reflowed at peak temperatures of 200, 220, 240, and 260 °C, with the time above 217 °C fixed at 40 s. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction were used to characterize the interfacial composition, morphology, layer thickness, grain size, and kernel average misorientation (KAM). The IMC layer thickened from 1.5 µm at 200 °C to 6.0 µm at 260 °C, while KAM_ave increased from 0.36° to 0.59°. At 220 °C, the IMC thickness changed only slightly to 1.6 µm, accompanied by local Pb and Ag enrichment. At 240 °C, the IMC thickness increased sharply to 4.7 µm and KAM_ave increased to 0.55°, together with larger Cu₆Sn₅ grains and localized coarsening. At 260 °C, the IMC thickness reached 6.0 µm and KAM_ave reached 0.59°, while Pb-rich regions became more pronounced and the Ag content decreased markedly, indicating substantial interfacial solute redistribution and increasingly heterogeneous IMC growth. The results link the reflow temperature to changes in interfacial chemistry, and microstructure and can help define a suitable process window for Pb-free/Pb mixed assembly. Full article

Konjac glucomannan (KGM), a natural hydrocolloid, is often recognized as an effective texturizing and stabilizing agent in flour-based products. This study systematically investigated the effects of KGM on wheat starch molecules and the gluten protein network. The results showed that different substitution levels (0–5%) of KGM influenced the gelatinization process of starch granules through a thickening effect and competitive hydration. This was specifically manifested as an increase in the pasting viscosity and gelatinization temperature of the system, along with a decrease in gelatinization enthalpy. For textural properties, the KGM addition reduced the hardness of wheat flour gels while enhancing their adhesiveness. Within the dough system, KGM significantly enhanced the gluten network stability, supported by increased water absorption and dough stability time, and decreased degree of softening. Meanwhile, the incorporation of KGM increased the tensile resistance of the dough but decreased the maximum elongation ratio. Furthermore, the storage modulus and loss modulus of the dough showed an increasing trend with higher KGM concentrations. In conclusion, KGM significantly influenced the physicochemical properties and final processing quality of the dough by binding with starch, cross-linking gluten networks, and altering water distribution. This study offered a theoretical foundation for KGM applications in optimizing flour-based product quality. Full article

The global prevalence of lung diseases has risen markedly over the past three decades, driven by factors such as population growth, harmful environmental exposures, and increased life expectancy. Epidemiological studies have highlighted not only the growing burden of chronic respiratory disorders but also the trend toward earlier onset across age groups. Early detection and timely treatment of these conditions are essential to improving long-term clinical outcomes and reducing premature mortality. Chest radiography (X-ray) remains the most widely used and cost-effective initial diagnostic tool for respiratory diseases. However, the reliable identification of multiple thoracic abnormalities, such as cardiomegaly, emphysema, hernia, infiltration, mass, nodules, atelectasis, pneumothorax, pleural thickening, pneumonia, fibrosis, consolidation, effusion and edema, poses challenges even for experienced radiologists. Recent advances in deep learning, particularly convolutional neural networks, have improved medical image analysis and classification. In this study, we propose DualPool-DenseNet121, a modified DenseNet121 architecture combining global average and global max pooling, for multi-label classification of thoracic abnormalities on the NIH ChestX-ray14 dataset. Following removal of “No Finding” cases, our analysis used 51,759 pathological radiographs from 14,402 patients, annotated for fourteen pathological conditions, partitioned patient-wise into training, validation, and test sets with verified zero patient overlap. The pipeline incorporates standardized preprocessing, offline augmentation of under-represented classes, staged transfer learning, and per-class decision thresholds selected on the validation set. Model performance was evaluated using per-class AUC together with threshold-based clinical metrics. The proposed model achieved a macro-averaged AUC of 0.803 and a micro-averaged AUC of 0.831 on the held-out test set. Zero-shot external validation on the CheXpert validation set reached a macro-averaged AUC of 0.806 across the five overlapping pathologies with sufficient positive cases. Grad-CAM visualizations indicated that, in correctly classified cases, the model frequently attended to anatomically relevant regions. These results suggest that the proposed approach provides a reliable and reproducible retrospective benchmark for multi-label thoracic abnormality classification. External validation and expert radiological assessment are required before any clinical application can be considered. Full article

Background: Over the past two decades, with the collaboration between periodontists and orthodontists, the concept of a surgically facilitated orthodontic therapy (SFOT) approach was developed, which not only provides acceleration in tooth movement as a result of a stimulated regional acceleratory phenomenon but also increases the alveolar bone volume for orthodontic tooth movement range by bone grafting. Despite the benefits, hard and soft tissue defects can sometimes be observed in patients post SFOT, especially among groups with thin periodontal phenotypes. Methods: In the current study, we compared the traditional SFOT with allograft only and the modified SFOT with allograft and collagen matrix to explore if the addition of a collagen matrix between the bone graft and periodontal flap could achieve soft tissue augmentation and reduce the prevalence of the complications of SFOT. Six patients were initially enrolled in the current study. Four patients showed up for the 1-week and 2-week post-operation evaluations. However, only one subject of each group agreed on periodontal evaluation by bone sounding and CBCT during the 6-month follow-up appointment. Results: Six months post SFOT, the patient with the modified SFOT presented with a larger amount of soft tissue thickening compared to the patient with traditional SFOT. However, the location of bone generation was different between groups, with the modified SFOT group presenting with bone generation more apically. In addition, patients with modified SFOT reported a more severe level of discomfort than patients with traditional SFOT. Conclusions: The modified SFOT may potentially improve soft tissue phenotype; however, further modifications are needed to reduce the patient’s discomfort level and to ensure that bone particles are contained more incisally. Full article

Sparganium stoloniferum tubers (SL), known medicinally as Sparganii Rhizoma, are commonly considered superior at the winter-harvest stage, when they show the traditional quality traits of heavy weight and firm texture. However, the developmental basis of this quality phenotype remains insufficiently understood. This study aimed to determine how tissue organization, cell-wall architecture, starch deposition, and related transcriptional patterns are associated with winter-harvest quality in SL. By comparing SL at different developmental stages, we found that maturation was accompanied by reduced moisture content, increased tuber density, higher parenchyma cell density, progressive cell-wall thickening, and marked starch accumulation. Laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) observations further revealed thickened multilamellar cell walls and abundant clustered or compound-like starch bodies in mature SL. Starch isolated from mature SL displayed an A-type crystalline pattern, short-range order, and high gelatinization and pasting temperatures, indicating an ordered and thermally stable starch matrix. Cell-wall Fourier-transform infrared spectroscopy (FTIR) and solid-state nuclear magnetic resonance (NMR) analyses showed a predominantly polysaccharide-rich framework with subtle maturation-associated changes in aromatic- and methoxy-associated wall signals. Transcript-guided pathway analysis, supported by reverse transcription quantitative polymerase chain reaction (RT–qPCR)validation, suggested developmental shifts in carbohydrate metabolism, lipid-related metabolism, and gibberellin-associated transcriptional patterns. Together, these findings indicate that winter-harvest quality in SL is associated with coordinated tissue consolidation, cell-wall maturation, starch deposition, and transcriptional reprogramming, providing a structural and molecular framework for understanding the traditional firm-texture trait of S. stoloniferum. Full article

High-temperature sintered conductive silver paste serves as a critical material in the fabrication of electronic components, with its performance directly influencing device reliability and integration density. In this work, conductive silver paste was prepared via a ball milling method by dispersing silver powder (conductive filler), glass powder (binder), and ethyl cellulose (EC, thickener) in an organic carrier composed of α-terpineol, diethylene glycol butyl ether acetate (DBA), and dimethyl phthalate (DMP) at specific ratios. The effects of the formulation composition and preparation process on the rheological properties of the paste as well as the electrical and mechanical properties of the resulting films were systematically investigated. The results indicated that sintering time and temperature exerted regular effects on the resistance of the silver paste; ball milling speed and duration influenced the particle size distribution, thereby affecting the resistance behavior; thixotropy significantly impacted the resistance characteristics. Under optimal conditions, where the organic carrier consisted of α-terpineol, DBA, and DMP at a ratio of 6:3:1, with 30 wt.% silver powder, 18 wt.% glass powder, and 4 wt.% EC, combined with a sintering temperature of 500 °C for 50–60 min, a ball milling speed of 500–600 r/min, and a ball milling time of approximately 1.5 h, the obtained silver paste exhibited pronounced shear-thinning behavior and excellent thixotropy, indicating favorable processability. The corresponding silver paste film demonstrated the lowest resistivity, superior bending resistance, and good adhesion to both PET and glass substrates. This study provides valuable insights for the design and preparation of high-performance, high-temperature sintered conductive silver pastes. Full article

Low-molecular-weight gelators (LMWGs) have attracted growing attention as versatile alternatives to conventional polymeric thickeners and gelators, owing to their ability to form three-dimensional fibrillar networks through non-covalent self-assembly and to undergo reversible sol–gel transitions in response to external stimuli. Among the various stimuli that can be exploited, pH represents a particularly attractive trigger given its direct relevance to biological and physiological environments. This review focuses on three categories of pH-responsive LMWGs that have shown notable progress over the past decade yet remain relatively underexplored in the literature. First, N-oxide-type hydrogelators are discussed, with emphasis on amide amine oxide-based surfactants and pyridine-N-oxide frameworks. The pH-dependent protonation of the N-oxide moiety modulates intermolecular hydrogen bonding, thereby governing self-assembly and gel formation. The structural versatility of these gelators enables rational tuning of aggregate morphology and confers clear pH and temperature responsiveness. Second, recent advances in phenylboronic acid-based LMWGs are highlighted. Although boronic acid derivatives have long been studied as dynamic crosslinking units in polymeric hydrogels, 3-isobutoxyphenylboronic acid was recently identified as the first example of phenylboronic acid functioning as an LMWG, in which gelation is driven primarily by hydrogen bonding and pH responsiveness is exploited for stimuli-triggered gel disruption rather than gel formation. Third, pH-responsive orthogonal self-assembly systems are reviewed. Representative examples include multicomponent hybrid hydrogels combining pH-activated LMWGs with polymer gelators for controlled drug release, pH-triggered self-sorting of two LMWGs without any polymeric component, and bio-based orthogonal hydrogels composed of a glucolipid LMWG and cellulose nanocrystals. For each system, both advantages and remaining limitations are critically assessed. Collectively, this review aims to provide a timely overview of emerging trends in pH-responsive LMWG research and to offer perspectives on the rational design of next-generation stimuli-responsive soft materials. Full article

Yam starch accounts for 70–80% of its dry matter, and its physicochemical and technofunctional properties are crucial for its use in the food industry (gelling agent, thickener, and stabilizer). The objective of this study focuses on the physicochemical, pasting and thermal properties of starch extracted from the yam varieties Dioscorea cayenensis, Dioscorea alata, and Dioscorea rotundata. The proximal composition, amylose and amylopectin content, as well as their functional properties (absorption index, solubility, swelling, thermal and pasting behavior, morphology, and color) were analyzed. The results showed that the starch extraction yield varied between varieties, being highest in D. cayenensis with 14.14%. D. alata had the highest starch (82.24%) and amylose (34.69%) content, which gives it greater gel firmness and retrogradation potential, as well as the best techno-functional properties water absorption index (2.46 g/g), water solubility index (1.1%), and swelling power (2.54 g/g). D. cayenensis stands out for its high amylopectin content (69.62%) and brightness (96.89), reflecting greater starch whiteness. D. rotundata has an intermediate balance between amylose and amylopectin, which makes it versatile. The proximal composition and techno-functional properties of yam starch position it as a promising raw material for the food industry, especially in the manufacture of thickeners, gelling agents, and in bakery products, pasta and noodles. Full article

Dysphagia and age-related oral processing limitations are rising with population aging and the growing burden of neurological diseases. Texture-modified diets remain the most common non-pharmacological intervention, yet conventional pureeing and thickening often yield meals with low visual appeal, variable textures, and diluted nutrient density, which contribute to reduced intake and malnutrition risk. Extrusion-based three-dimensional food printing, especially when combined with gel-derived edible inks, offers a digital route to standardize geometry, portioning, and texture while enabling individualized nutrition and sensory design. In the past three years, the field has progressed from simple single-ingredient pastes to engineered soft-matter systems including emulsion gels, high-internal-phase emulsion gels, Pickering-stabilized gels, bigels, and multi-material constructs enabled by dual and coaxial printing. These advances are underpinned by improved rheological windowing, microstructure engineering, and post-print gelation strategies such as ionic crosslinking, thermal setting, enzymatic bridging, and pH-triggered network formation. Meanwhile, dysphagia-oriented product development has matured from “shape recovery” demonstrations toward clinically relevant texture targets, leveraging the IDDSI tests to anchor swallowability. This review synthesizes the recent literature across materials science, food engineering, and clinical nutrition to connect gel microstructure to extrusion performance, post-processing stability, and oral processing outcomes that are relevant to older adults and dysphagia patients. We propose design principles for gel network selection, phase structuring, and process control that simultaneously satisfy print fidelity and swallowing safety targets. Full article

Canna (Canna edulis Ker.) starch is an important non-conventional starch in global applications. In this study, the structural and physicochemical properties of canna starches extracted from four different geographical regions in China were investigated. The four starches (CES-DH, CES-MS, CES-YB, and CES-YX) exhibited relatively high total starch contents (82.51–93.22%). Apparent and true amylose contents varied markedly among samples, ranging from 31.44% to 43.62% and from 15.21% to 35.90%, respectively. Morphologically, the granules were oval and disc-shaped, with D₅₀ values of 20.19–48.35 μm. CES-YX showed a distinct C-type pattern, while other starches exhibited B-type crystallinity, and relatively crystallinity values among samples were between 20.53% and 25.36%. IR absorbance ratios R_1047/1022 and R_995/1022 varied from 0.56 to 0.63 and from 1.15 to 1.26, respectively. Gelatinization temperatures and enthalpy revealed distinct thermal behaviors among the starches, corresponding to substantial differences in pasting properties with wide ranges in peak, breakdown, and setback viscosities. All starch pastes exhibited shear-thinning behaviors and weak gel characteristics. Notably, CES-YB demonstrated high potential as an effective food thickener and stabilizer, as distinguished by the high final viscosity and consistency coefficient (K), whereas the high amylose and resistant starch content in CES-YX made it a promising ingredient for low-glycemic-index food formulations. These findings provided a theoretical basis and practical guidance for the targeted utilization of canna starch in the food industry. Full article

To test whether fructooligosaccharide (FOS) and inulin (INU) molecules can improve the hardness of cooked rice through forming a hydrogel network, we added FOS or INU at 0%, 3%, 5%, 7%, and 10% concentrations to two cooking japonica rice and compared the cooking and textural parameters, the pasting, thermal, and thermo-mechanical properties, and the microstructure of the cooked rice. General Linear Model Univariate (GLMU) analysis revealed that, compared with no oligofructose addition, both FOS and INU addition reduced the rice cooking time and increased the gruel solid loss. The addition of these dietary fibers (DFs) to cooking rice lowered the hardness, adhesiveness, springiness, gumminess, and chewiness of the rice, but maintained the cohesiveness and increased the resilience. Compared with no oligofructose addition, FOS and INU addition improved the smell, taste, and total sensory score of cooked rice. The addition of these DFs significantly decreased the trough, peak, final, breakdown, and setback viscosities, but increased the pasting temperature and peak time. Both FOS and INU addition decreased the enthalpy of gelatinization but increased the peak and conclusion temperature of gelatinization of rice flour paste. After the retrograded flour pastes were kept at 4 °C for 21 days, both FOS and INU significantly increased amylopectin aging compared with no oligofructose addition. The FOS-added and INU-added rice doughs had a higher dough development time and stability time, gelatinization peak torque, setback torque, and gelatinization speed, with a lower protein weakening degree, amylase activity, breakdown torque, heating speed, and enzymatic hydrolysis speed. Compared with no oligofructose addition, both FOS and INU addition reduced the amorphous region of starch and β-sheet percentage, but increased the percentages of random coils, α-helixes, and β-turns in cooked rice. Principal component analysis (PCA) further demonstrated that the gruel solid loss, cooked rice hardness, chewiness, gumminess, taste, and the peak, trough, breakdown, final, and setback viscosities were sensitive parameters for evaluating the effects of species and the amount of oligofructose addition on rice quality. The microstructure showed that FOS or INU addition induced thickening of the matrix walls and an increase in the pore size, forming a soft and evenly swollen structure. These results suggest that FOS or INU addition inhibits amylose recrystallization but maintains amylopectin recrystallization in cooked rice, with INU addition producing greater improvements in the texture and sensory scores of cooked rice compared withFOS addition. This study provides evidence of the advantages of adding DFs and probiotics such as INU and FOS to cooked rice. Full article

Balancing high fluidity and stability is a critical challenge in deep-shaft cemented paste backfill (CPB) with high-concentration tailings. This study investigates the synergistic regulation mechanism of a combined admixture system comprising hydroxypropyl methylcellulose (HPMC) thickener and polycarboxylate (PCE) or Melamine-Formaldehyde Resin (MFR) superplasticizers on CPB rheology, mechanical strength, and microstructure. Results indicate that HPMC significantly enhanced anti-segregation performance via intermolecular bridging, substantially increasing yield stress and plastic viscosity. Upon PCE introduction, the steric hindrance provided by its side chains effectively disrupted HPMC-induced flocs and released entrapped water. Consequently, yield stress and plastic viscosity were reduced by up to 22.1% and 64.3%, respectively, with PCE exhibiting markedly superior viscosity-reducing efficiency compared to MFR. Mechanical testing revealed that PCE co-addition did not compromise early-age strength but enhanced 3, 7, and 28-day unconfined compressive strength (UCS) by refining pore structures and promoting the uniform distribution of hydration products. Microstructural analysis unveiled a competitive adsorption mechanism: preferential PCE adsorption dispersed particle agglomerates, while non-adsorbed HPMC formed a viscoelastic network within the pore solution, constructing a stable “dispersion-suspension” microstructure. This work provides a theoretical basis for optimizing high-performance backfill formulations. Full article

This study compares the mechanisms of organic (Hydroxypropyl Methyl Cellulose, HPMC) and inorganic (bentonite) thickeners in regulating the bleeding behavior and surface homogeneity of cement pastes. In situ low-field nuclear magnetic resonance (LF-NMR) was employed to monitor water migration, while X-ray diffraction (XRD), scanning electron microscopy (SEM), and carbonation tests were conducted to evaluate the property disparities between the top surface and bottom layers. Results indicate fundamentally different working modes: HPMC reduces bleeding by swelling to block capillary channels, exhibiting a saturation threshold at 0.2% dosage. Beyond this point, as the primary transport channels are effectively sealed, additional HPMC merely densifies the polymer “plugs” without further suppressing the bleeding rate. XRD and SEM analyses reveal that despite the reduction in total bleeding, HPMC-modified pastes still exhibit significant stratification; the top layer retains a loose, granular morphology with higher carbonation susceptibility compared to the dense bottom layer. In contrast, bentonite mitigates bleeding through a volume-filling mechanism and thixotropic structuring, demonstrating a continuous, dosage-dependent efficacy up to 1.2%. At a 0.6% dosage, bentonite effectively eliminates microstructural disparities, yielding a top surface with a dense matrix and hydration product distribution nearly identical to the bottom layer. These findings demonstrate that the specific inorganic thickener (bentonite) utilized in this work is more effective in restoring surface homogeneity and enhancing carbonation resistance than the evaluated organic polymer (HPMC). Full article

We show that epistemic uncertainty–our iterated ignorance about our own ignorance–inevitably thickens statistical tails, even under perceived thin-tailed environments from past realizations. Any claim of precise risk carries a margin of error, and that margin itself is uncertain, in an infinite regress of doubt. This “errors-on-errors” mechanism rules out thin-tailed certainty: predictive laws must be heavier-tailed than their in-sample counterparts. The result is the Forecasting Paradox: the future is structurally more extreme than the past. This insight collapses branching scenarios into a single heavy-tailed forecast, with direct implications for risk management, scientific modeling, and AI safety. Full article

Numerous studies have been published on various rheological aspects of conventional and high-performance concrete, some of which encompass multi-scale investigations. However, there is no published article that studies the rheology of ultra-high-performance concrete (UHPC) with a multi-scale approach. In this paper, a comprehensive investigation into the rheological properties of UHPC at three cementitious material scales was undertaken: the paste scale, the high-strength mortar scale, and the fiber-reinforced composite scale. The effect of cement type, supplementary cementitious materials (SCMs), and the water-to-binder ratio (w/b) on the rheology of UHPC at various material scales was evaluated using the appropriate rheometric apparatus. The results indicated that all of the UHPC mixtures in this study exhibited shear thickening behavior, and the degree of shear thickening increased as the w/b decreased. This phenomenon was systematically quantified at the paste, high-strength mortar, and fiber-reinforced composite scales, enabling direct comparison across material levels. Notably, the incorporation of silica fume suppressed the shear thickening behavior, as evidenced by the disappearance of the second-order term in the modified Bingham model, whereas slag had no such effect. The 28-day compressive strength of the investigated UHPC mixtures ranged between 100 and 150 MPa, and the mixture prepared with a combination of cement and silica fume (90C10SF) exhibited 35% higher compressive strength compared to the mixture prepared with cement and slag (90C10SL). Additionally, the UHPC mixture prepared with 90C10SF binder combination showed a 20% higher load-carrying capacity compared to the UHPC mixture made with 90C10SL and 80C10SL10SF binder combination. Full article