Search Results (1,118)

With the rapid advancement in portable electronics, artificial intelligence, and the Internet of Things, there is an escalating demand for high-density, low-voltage non-volatile memory (NVM) technologies. Germanium (Ge) nanocrystals (NCs) have emerged as a promising candidate for NVM applications; however, traditional synthesis methodologies suffer from limitations in achieving precise control over the size and density of these nanocrystals, which exert a significant influence on device performance. This study presents an innovative Ag-catalyzed chemical vapor deposition (CVD) methodology for the synthesis of Ge NCs with precisely controllable size and density on SiO₂/Si substrates, tailored for NVM applications. Scanning electron microscopy characterization confirms the successful growth of faceted Ge NCs. Electrical characterization of the fabricated devices reveals that Ge NCs grown at temperatures ranging from 700 to 1000 °C exhibit memory windows spanning from 3.0 to 6.8 V under a ±6 V bias. Notably, the device synthesized at 900 °C demonstrates an exceptional memory window of 7.0 V under a ±8 V bias. Furthermore, the Ge NC-based NVM devices exhibit excellent charge retention characteristics. Specifically, for the device with Ge NCs grown at 700 °C, the time required to retain charge from 100% to 95% of its initial value exceeds 10 years, demonstrating long-term stable charge storage capability. These findings underscore the significant potential of this approach for the development of high-performance NVM technologies. Full article

Insects achieve millisecond sensor–motor loops with tiny sensors, compact neural circuits, and powerful actuators, embodying the principles of Edge AI. We present a comprehensive architectural blueprint translating insect neurobiology into a hardware–software stack: a latency-first control hierarchy that partitions tasks between a fast, dedicated Reflex Tier and a slower, robust Policy Tier, with explicit WCET envelopes and freedom-from-interference boundaries. This architecture is realized through a neuromorphic Reflex Island utilizing spintronic primitives, specifically MRAM synapses (for non-volatile, innate memory) and spin-torque nano-oscillator (STNO) reservoirs (for temporal processing), to enable instant-on, memory-centric reflexes. Furthermore, we formalize the biological governance mechanisms, demonstrating that, unlike conventional ICEs and miniturbines that exhibit narrow best-efficiency islands, insects utilize active thermoregulation and DGC (Discontinuous Gas Exchange) to maintain nearly constant energy efficiency across a broad operational load by actively managing their thermal set-point, which we map into thermal-debt and burst-budget controllers. We instantiate this integrated bio-inspired model in an insect-like IFEVS thruster, a solar cargo e-bike with a neuromorphic safety shell, and other safety-critical edge systems, providing concrete efficiency comparisons, latency, energy budgets, and safety-case hooks that support certification and adoption across autonomous domains. Full article

Traditional herbal prescriptions composed of multiple botanicals remain central to ethnopharmacological practice; however, their chemical basis and classification remain poorly understood. Non-volatile compound analyses of herbal medicines are well established, but comparative studies focusing on volatile organic compounds (VOCs) across multi-herbal prescriptions are scarce. To enhance the chemical understanding of traditional formulations and clarify prescription-level characteristics, this study applied headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME–GC–MS) to characterize VOC-based chemical signatures in 30 prescriptions composed of 76 herbal ingredients. Multivariate analyses such as principal component analysis, partial least squares discriminant analysis (PLS-DA), and orthogonal PLS-DA (OPLS-DA) enabled systematic differentiation of various prescriptions and identified 25 discriminant VOCs, 9 of which were common among multiple therapeutic categories. These shared compounds, such as 5-hydroxymethylfurfural (5-HMF) and 4H-pyran-4-one derivatives, reflect recurrent chemical patterns associated with broad-spectrum applications, whereas category-specific volatiles (including isopsoralen, senkyunolide, and fenipentol) delineated therapeutic boundaries, even among prescriptions with overlapping botanicals. Capturing both shared and distinct volatile signatures clarified ambiguous boundaries between categories such as cold, inflammation, or diabetes versus kidney disorder prescriptions, thereby linking chemical patterns with ethnopharmacological indications. Together, these findings highlight VOC profiling as a valuable diagnostic and interpretive tool that bridges traditional categorization systems with modern chemical analysis, offering a robust framework for future pharmacological and mechanistic investigations. Such an approach not only substantiates traditional categorization but also provides a practical basis for quality control and pharmacological evaluation of multi-herbal formulations. Full article

Background/Objectives: Coleus aromaticus (Lamiaceae), also known as Cuban oregano or Indian borage, is a semi-succulent perennial species widely used in traditional medicine for its therapeutic and nutritional properties. While its essential oils and aromatic fraction have been extensively investigated, the characterization of its non-volatile metabolites remains limited. The aim of this study was to explore the chemical composition of fresh leaves with a focus on the non-volatile fraction. Methods: Fresh leaves of C. aromaticus were cryogenically treated with liquid nitrogen, ground, and subjected to three different extraction procedures: hydroalcoholic maceration, ethyl acetate maceration, and liquid–liquid partitioning to obtain a dichloromethane organic phase and a hydroalcoholic phase. Extracts and fractions were analyzed by HPTLC and HPLC for metabolic profiling. In addition, the Bligh–Dyer method was applied to separate polar and non-polar metabolites, which were subsequently characterized using NMR spectroscopy. Results: Chromatographic analyses highlighted the occurrence and distribution of organic acids, polyphenols (notably flavonoids), and proteinogenic amino acids. Spectroscopic data confirmed the presence of diverse polar and non-polar metabolites, providing a more detailed chemical fingerprint of C. aromaticus. This integrated approach broadened the phytochemical profile of the species beyond the well-documented essential oils. Conclusions: The results contribute to a better understanding of the non-volatile metabolites of C. aromaticus, offering novel insights into its chemical diversity. These findings highlight the potential of this plant as a valuable source of bioactive compounds, supporting its future application in nutraceutical and pharmaceutical research. Full article

Cucumis metuliferus E. Mey or kiwano/African horned melon is a good source of bioactive compounds of various pharmacological and industrial importance. This study investigated metabolomic shifts in in vitro cultivated kiwano plants over ten weeks of maturity time through GC-MS and LC-HRMS-MS untargeted analysis of volatile and non-volatile metabolites. Furthermore, in silico screening of the highly abundant volatile compounds from each sample was performed against three different proteins and enzymes of Candida spp. These results obtained from GC-MS and LC-HRMS-MS analysis highlight the potential of in vitro culture for enhancing the biosynthetic potential of C. metuliferus for sustainable and controlled production of target metabolites. Furthermore, this work also highlights the potential inhibitory properties of abundant volatile compounds in each stage of maturation period of C. metuliferus, providing a platform for further exploration of the therapeutic applications of C. metuliferus metabolites against Candida spp. Full article

Alcohol level is a critical quality parameter in Chinese baijiu, significantly influencing its flavor profile, sensory characteristics, and overall quality, which in turn affect consumer preferences and the development of the liquor industry. Understanding the non-volatile compounds in strong-flavor baijiu (SFB) is essential for elucidating its taste and mouthfeel characteristics. This study aims to identify non-volatile compounds using a non-targeted metabolomics approach and investigate the differences between high- and low-alcohol SFB from the Jiangsu region. A total of 647 non-volatile compounds were quantified. The key differential metabolites were screened among different samples. In total, 110 key differential non-volatile compounds were identified and quantified, which displayed significant differences between high- and low-alcohol SFB samples and showed notable similarities in compound types. Furthermore, the variation in non-volatile profiles among samples of the same brand but different alcohol levels was investigated. The different brands and origins of SFB samples were identified using OPLS-DA. The results indicated that the key non-volatile metabolites in most of the high-alcohol samples were higher than those in low-alcohol samples. This study provides valuable insights into the impact of alcohol level on the non-volatile composition of SFB, offering a theoretical foundation for flavor characterization, quality control, and standardization in baijiu production. Full article

Geographical origin constitutes one of the key factors that exert an influence on chemical compounds of Lonicerae japonicae flos (LJF). The present research was designed to explore differences among volatile organic compounds (VOCs) and non-VOCs among LJF samples from four geographical origins. Selection of 32 LJF samples with similar genetic backgrounds was performed using simple sequence repeat markers. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) were utilized to analyze VOCs, while non-VOCs were detected via ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Multivariate statistical analyses were applied to screen differential compounds. The results indicated that HS-SPME-GC-MS and HS-GC-IMS identified 80 and 57 VOCs, respectively, with 34 key differential VOCs screened out, exhibiting significant variations among origins. For non-VOCs, 130 compounds were identified, with 19 key differential compounds showing geographical differences. This study further facilitates a comprehensive understanding of the chemical composition of LJF from different origins. Full article

Giant pandas feed preferentially on bamboo but choose different species and organs depending on factors such as the altitude and season, suggesting preferential selection according to their nutritional requirements. However, the mechanism of selection is unclear. Pandas cannot directly sense the nutritional quality of bamboo shoots but tend to sniff their food before consumption, inferring that odors inform their choice, which is then reinforced by the selection of positive and negative taste cues. To investigate the basis of selection, we observed the effects of 10 different bamboo species on feeding behavior, including food item selection, feeding frequency, portion size, food processing time per bite, and amount consumed per meal. Three of the bamboos were preferred, another four were consumed when the preferable bamboos were unavailable, and the remaining three were always rejected. We then characterized the volatile components of the bamboo leaves as well as the primary and secondary metabolites, allowing us, for the first time, to correlate feeding behavior with metabolomics. The three groups shared some volatile compounds but 21 volatiles were unique to the preferred leaves and appeared to confer sweet and fresh aromas, whereas the inedible leaves produced 20 unique volatiles that were pungent or floral, which appeared to discourage feeding. The three groups also shared many common nonvolatile metabolites, but pairwise comparisons revealed both qualitative and quantitative differences in metabolite abundance that resulted in the preferred leaves accumulating compounds associated with a sweet taste in humans (e.g., sugars), while the inedible leaves contained metabolites often associated with sour and bitter tastes (e.g., certain flavonoids and acids). Following attraction by certain volatiles, giant pandas may therefore consolidate their selection of leaves that are potentially more nutritious by consuming those with sweeter, less bitter and less sour tastes. Full article

Bee pollen is a natural nutrient substance collected by bees from plants. Its metabolites have been extensively studied, yet the characteristic metabolites of bee pollen from different floral sources have not been clearly identified. In this study, we collected four types of bee pollen (tea, rose, rapeseed, and corn pollen) from across China and analyzed their volatile and non-volatile metabolites using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) and gas chromatography-mass spectrometry (GC-MS). At the same time, the nutritional substances (Including polyphenols, organic acids, and sugars) were precisely quantified. The results showed that the total phenols (5 mg GAE/g) and total flavonoids (0.27 mg RE/g) content of corn pollen were significantly higher (p < 0.05) than those of other pollens, and the contents of polyphenols such as naringenin were relatively high, indicating strong antioxidant potential. Rose pollen was rich in protein (0.04 g/g) and flavonoid glycosides. Tea pollen was prominent in the content of polyphenol glycosides and amino acid derivatives, while rapeseed pollen performed well in phenolic acids (Ferulic acid), as well as specific sugar (Mannose). We identified the differential metabolites of these bee pollen through orthogonal partial least squares discriminant analysis (OPLS-DA) (VIP > 1). It was also stipulated that metabolites with a VIP value greater than 1.5 showed significant differences and could be used as characteristic metabolites for differentiating pollen (p < 0.05). The representative metabolites of bee pollen were as follows: rapeseed pollen—ferulic acid; tea pollen—malic acid; corn pollen—epicatechin; and rose pollen—fumaric acid. This study provides a research basis for evaluating the quality, traceability, and metabolite exploration of bee pollen. Full article

Recent advancements in nanotechnology have intensified research efforts to address security concerns like hardware trojans and intellectual property (IP) piracy, particularly by exploring novel alternatives to traditional MOSFET devices. Spin-based devices, known for their low power consumption, non-volatility, and seamless integration with silicon substrates, have emerged as promising candidates. This research proposes a novel approach to enhance the security of integrated circuits using spin-based devices known as magnetic tunnel junctions (MTJs). A Non-volatile Polymorphic Logic (NPL) is optimized and designed to perform multiple operations, effectively concealing its true functionality. The analytical studies conducted on the Cadence Virtuoso platform using TSMC 65 nm MOS technology demonstrate the feasibility and efficacy of the proposed approach. The proposed NPL circuit enables polymorphism by allowing the circuit to perform all one- and two-input Boolean logic operations, including NOT, AND/NAND, OR/NOR, and XOR/XNOR, through adjustments of applied keys. This dynamic functionality makes it challenging for attackers to determine the circuit’s true operation. The proposed design exhibits similar timing characteristics for different logic operations, which further complicates the tampering attempts. Additionally, the circuit’s layout is designed to be symmetric, ensuring the execution of all possible operations by the same physical layout. This provides post-manufacturing security from reverse engineering and finds its applications in securing custom IC designs against the evolving landscape of hardware-based threats. Full article

Aluminum scandium nitride (Al_1−xSc_xN) is a promising ferroelectric material for non-volatile random-access memory devices and electromechanical sensors. However, adverse effects on polarization from electrical leakage are a significant concern for this material. We observed that the electrical conductivity of Al_1−xSc_xN thin films grown on epitaxial TiN(111) buffered Si(111) follows an Arrhenius-type behavior versus the growth temperature, suggesting that point defect incorporation during growth influences the electronic properties of the film. Photoluminescence intensity shows an inverse correlation with growth temperature, which is consistent with increased non-radiative recombination from point defects. Further characterization using secondary ion mass spectrometry in a focused ion beam/scanning electron microscope shows a correlation between trace Ti concentrations in Al_1−xSc_xN films and the growth temperature, further suggesting that extrinsic dopants or alloying components potentially contribute to the point defect chemistry to influence electrical transport. Investigation of the enthalpy of formation of nitrogen vacancies in Al_1−xSc_xN using density functional theory yields values that are in line with electrical conductivity measurements. Additionally, the dependence of nitrogen-vacancy formation energy on proximity to Sc atoms suggests that variations in the local structure may contribute to the occurrence of point defects, which, in turn, can impact electrical leakage. Furthermore, we have demonstrated ferroelectric behavior through electrical measurements and piezoresponse force microscopy after dc bias poling of films in spite of electrical conductivity spanning several orders of magnitude. Although electrical leakage remains a challenge in Al_1−xSc_xN, the material holds potential due to tunable electrical conductivity as a semiconducting ferroelectric material. Full article

Eruca sativa Mill. (rocket; Fam. Brassicaceae) is widely appreciated for its peculiar flavour and beneficial effects on human health. Glucosinolates (GSLs) and their enzymatic hydrolysis products, isothiocyanates (ITCs), are considered to be responsible for health-promoting effects and for sensory relevance in rocket, respectively. This study aimed at evaluating and comparing the metabolite profiles of rocket leaves collected at different phenological stages, to investigate the content evolution during cultivation. To minimise metabolic variability induced by environmental factors, plants were cultivated in an innovative growing system equipped with precision lighting and ventilation. A multi-platform metabolomics approach combining liquid chromatography–high-resolution mass spectrometry (LC–HRMS) and headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC–MS) was carried out for comprehensive coverage of non-volatile and volatile organic compounds (VOCs). To integrate data from both platforms, a multivariate data fusion strategy was used. Higher GSLs content was detected in the microgreens stage. In particular, glucoraphanin, glucoiberverin, glucoerucin, DMB-GLS, and 1,4-dimethoxyglucobrassicin were identified as biological markers of rocket microgreens. ITCs levels were found to increase in mature leaves. These findings suggest a dynamic modulation of secondary metabolism during the plant life cycle, possibly in response to different adaptation needs to environmental conditions. Our findings confirm the potential of microgreens as a functional food in promoting health and preventing chronic diseases and can also tailor rocket cultivation to maximise the production of beneficial metabolites and to improve selected sensorial features. Full article

Ziziphi Spinosae semen (ZSS) is renowned for its rich nutritional composition and is traditionally consumed in China, Japan, and Korea, where it is widely incorporated into both medicinal diets and daily cuisine. To address the lack of systematic research comparing raw and fried ZSS, this study aimed to elucidate the compositional and functional changes induced by the frying process. This study systematically compared the chemical profiles and antioxidant activities of ZSS and fried ZSS using ultra-performance liquid chromatography–quadrupole–time-of-flight mass spectrometry (UPLC–Q–TOF–MS) and gas chromatography–ion mobility spectrometry (GC–IMS). A total of 92 non-volatile compounds and 43 volatile organic compounds (VOCs) were identified. Frying significantly promoted the formation of polar compounds such as flavonoids and saponins and increased the content of aldehydes and alcohols, thereby generating aromas characteristic of Maillard reactions and lipid oxidation. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) clearly distinguished the two groups in terms of their chemical composition and flavor characteristics. In addition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays demonstrated that the antioxidant capacity of fried ZSS was significantly higher than that of the raw sample (p < 0.05). These results indicate that the frying process reshapes the chemical properties and bioactivity of ZSS via multiple pathways, including glycoside hydrolysis, lipid oxidation, and Maillard reactions. Overall, this study establishes a scientific foundation for the development of functional foods derived from ZSS. Full article

Charge-trapping memory (CTM) is a viable contender to supersede the floating gate technology in high-density flash memory applications. To this end, very reliable charge storage in CTM should be secured. This requires optimization of trap density, their energy and spatial location as well as a deep understanding of their origin. In this work, we used X-ray photoelectron spectroscopy (XPS) to investigate chemical bonds in nanolaminated and doped HfO₂/Al₂O₃ stacks in an effort to gain insight into the nature of defects in the electron/hole trapping processes. The impact of Al incorporation into the HfO₂ and rapid thermal annealing (RTA) in O₂ on the composition, stoichiometry and bonding configurations was studied. Incorporation of Al into HfO₂ leads to an increased concentration of Hf-suboxides. Subsequent RTA effectively reduces suboxides, enhances the stoichiometry of the HfO₂/Al₂O₃ stacks and facilitates intermixing at the dielectric interface, resulting in the formation of Hf–Al–O bonds. The valence band spectra indicate that both Al incorporation and RTA change the dielectric/Si band alignment in a similar way, lowering the valence band offset. The observed changes were considered in relation to the electrically active defects and traps in the structures. Full article

To characterize the key odorants and elucidate the flavor profiles of compound fermented beverages after fermentation, single-compound fermented beverages (GW, AW) and a compound fermented beverage (CW) were prepared using Italian Riesling grapes and SirPrize apples as raw materials. The flavor and metabolite profiles were systematically analyzed by integrating flavoromics (comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry, GC × GC–TOF MS) and metabolomics (LC–MS/MS). The results demonstrated that CW exhibited the most favorable acid/reducing sugars (2.18), imparting a drier taste and superior stability. Compounds with relative odor activity values (rOAV) greater than 1—including 3-methyl-1-butyl acetate, ethyl hexanoate, ethyl butanoate, and ethyl octanoate—collectively contributed prominent fruity, floral, and sweet aromas to all three wine types. Ethyl decanoate provided an additional distinctive traditional fruity note specifically to AW, while 1-octen-3-ol contributed a mushroom-like aroma to both GW and CW. Moreover, 3-methylbutanal, 4-ethyl-2-methoxyphenol, and ethyl 3-methylbutanoate added additional significant aroma contributions to CW, imparting floral, clove-like, and fruity notes, respectively. Notably, ethyl hexanoate (fruity aroma) exhibited a remarkably high rOAV of 27.43 in CW, significantly surpassing its levels in the single-substrate fermentations. Lipid metabolism and the phenylpropanoid pathway were significantly activated in CW, facilitating the coordinated synthesis of esters and phenolic compounds. Sensory attribute network analysis further confirmed that CW possessed more pronounced “sweet”, “fruity”, and “floral” characteristics. Correlation analysis revealed significant relationships between volatile organic compounds (VOCs) and total soluble solids (TS), titratable acidity (TA), the TA/TS ratio, and metabolite levels, underscoring the close connections among physicochemical properties, precursor/intermediate metabolites, and flavor formation. Comprehensive analysis of non-volatile metabolites and flavor-associated VOCs revealed variety-specific characteristics and compounding effects, providing valuable insights for enhancing the quality of compound fermented beverages. Full article