Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (158)

Search Parameters:
Keywords = dark counts

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
26 pages, 914 KB  
Article
AI-Amplification Indicator: An Actor-Level Scoring Framework for Ransomware Operations on the Dark Web
by Mostafa Moallim, Seokhee Lee, Ibrahim Alzahrani, Faisal Abdulaziz Alfouzan and Kyounggon Kim
J. Cybersecur. Priv. 2026, 6(2), 70; https://doi.org/10.3390/jcp6020070 - 8 Apr 2026
Viewed by 88
Abstract
Ransomware operations have evolved from isolated malware incidents into organized ransomware-as-a-service (RaaS) ecosystems that employ coordinated tactics, techniques, and procedures and increasingly rely on automation and artificial intelligence to scale intrusions. However, most assessments remain artifact-centric, focusing on malware signatures or aggregate victim [...] Read more.
Ransomware operations have evolved from isolated malware incidents into organized ransomware-as-a-service (RaaS) ecosystems that employ coordinated tactics, techniques, and procedures and increasingly rely on automation and artificial intelligence to scale intrusions. However, most assessments remain artifact-centric, focusing on malware signatures or aggregate victim counts, which provide limited visibility into differences in actor-level behavior and operational capability. This study introduces the AI-Amplification Indicator (AIAI), an interpretable actor-level scoring framework that transforms publicly observable leak-site disclosures and verifiable open-source evidence into quantitative behavioral profiles. Using continuous monitoring of dark web leak portals, we construct a standardized dataset of ransomware disclosures for 2025 with temporal, geographic, and sector metadata. AIAI measures four complementary dimensions: GenAI-enabled social engineering, operational tempo and orchestration, targeting breadth and diversification, and temporal scaling dynamics. Indicators are computed for all observed actors, while comparative profiling focuses on the ten most active actors to ensure stable behavioral estimation. The analysis reveals substantial heterogeneity in posting cadence, targeting strategies, and scaling dynamics, as well as limited but measurable evidence of automated or AI-assisted deception. These differences are not captured by victim counts alone. The proposed framework provides a transparent and reproducible approach for actor-level ransomware intelligence, enabling systematic comparison of operational styles and supporting data-driven defensive prioritization. Full article
(This article belongs to the Section Security Engineering & Applications)
Show Figures

Figure 1

12 pages, 6028 KB  
Article
A Universal Deep Learning Model for Predicting Detection Performance and Single-Event Effects of SPAD Devices
by Yilei Chen, Jin Huang, Yuxiang Zeng, Yi Jiang, Shulong Wang, Shupeng Chen and Hongxia Liu
Micromachines 2026, 17(4), 452; https://doi.org/10.3390/mi17040452 - 7 Apr 2026
Viewed by 160
Abstract
Single-event effects (SEEs) present a significant challenge to the radiation reliability of integrated circuits. Conventional SEE analysis methods for single-photon avalanche diode (SPAD) devices primarily rely on Sentaurus Technology Computer-Aided Design (TCAD) numerical simulation, which is computationally intensive and time-consuming. In this study, [...] Read more.
Single-event effects (SEEs) present a significant challenge to the radiation reliability of integrated circuits. Conventional SEE analysis methods for single-photon avalanche diode (SPAD) devices primarily rely on Sentaurus Technology Computer-Aided Design (TCAD) numerical simulation, which is computationally intensive and time-consuming. In this study, we propose a generalized deep learning (DL) model, using a silicon-based SPAD device with a double-junction double-buried-layer (DJDB) structure fabricated in 180 nm CMOS process as the research subject. By incorporating key parameters that influence SEEs as model inputs, the proposed approach enables rapid prediction of critical parameter metrics, including transient current peaks and dark count rates. Experimental results show that the DL model achieves a prediction accuracy of 97.32% for transient current peaks and 99.87% for dark count rates, demonstrating extremely high prediction precision. To further validate the generalization capability of the proposed network, the model is applied to predict the detection performance of the DJDB-SPAD device. The prediction accuracies for four key performance parameters all exceed 97.5%, further confirming the accuracy and robustness of the developed model. Meanwhile, compared with the conventional Sentaurus TCAD simulation method, the proposed method achieves a 336-fold improvement in computational efficiency. Overall, this method realizes the dual advantages of high precision and high efficiency, which provides an efficient and accurate technical solution for the rapid characteristic analysis and reliability evaluation of SPAD devices under single-event effects (SEEs). Full article
Show Figures

Figure 1

16 pages, 2498 KB  
Article
Stage-Dependent Persistence of Nucleated Endosperm Cells in Seeds of Limonium Sexual and Apomictic Species with Autonomous Endosperm Formation
by Catarina Gomes-Domingues, Elvira Hörandl and Ana D. Caperta
Genes 2026, 17(3), 337; https://doi.org/10.3390/genes17030337 - 18 Mar 2026
Viewed by 264
Abstract
Limonium Mill. species present a polymorphic sexual system associated with flower polymorphisms like ancillary pollen and stigma, with sexual and/or apomictic reproduction. The aim of this study was to investigate the reproductive traits, test for autonomous apomixis, and assess seed formation in triploid [...] Read more.
Limonium Mill. species present a polymorphic sexual system associated with flower polymorphisms like ancillary pollen and stigma, with sexual and/or apomictic reproduction. The aim of this study was to investigate the reproductive traits, test for autonomous apomixis, and assess seed formation in triploid Limonium algarvense and Limonium daveaui. Pollen-stigma combinations were determined and the number of flowers and seeds counted. Single-seed flow cytometry was performed using seeds in three phenological stages: immature (stage I), early maturing (stage II) and mature seeds (stage III). The findings revealed that all triploid plants were self-sterile and produced seeds in the absence of pollination. Despite L. daveaui having a higher number of flowers than L. algarvense, a significantly higher ratio of seeds/flowers was observed in the latter species. Stage-dependent endosperm developmental patterns were observed, with nucleated cells present in stage II seeds with a light brown or pinkish coat, and an embryo peak and an endosperm peak with the double ploidy level. Stage III seeds, with a dark brown coat, presented only an embryo peak. Additionally, a single hexaploid endosperm peak was detected in stage I seeds, revealing early initiation of the endosperm with nucleated cells prior to embryo development. The single 6C endosperm peak was always associated with shrunken and wrinkled or underdeveloped stage I seeds but was never detected in stage II seeds. Overall, our results support reproduction via asexually formed seeds with pollen-independent endosperm formation and allow the identification of phenological development stages and seed coat morphological markers associated with single-seed flow cytometric screening patterns in apomictic species. Full article
(This article belongs to the Section Cytogenomics)
Show Figures

Figure 1

13 pages, 3283 KB  
Article
Comprehensive Comparison of Front- and Back-Illuminated Single-Photon Avalanche Diodes in 110 nm Standard CMOS Image Sensor Technology
by Doyoon Eom, Won-Yong Ha, Eunsung Park, Jung-Hoon Chun, Jaehyuk Choi, Woo-Young Choi and Myung-Jae Lee
Sensors 2026, 26(5), 1664; https://doi.org/10.3390/s26051664 - 6 Mar 2026
Viewed by 647
Abstract
This paper presents a process-controlled study of illumination engineering in single-photon avalanche diodes (SPADs) fabricated in a 110 nm standard CMOS image sensor (CIS) technology. Front-illuminated (FI) and back-illuminated (BI) SPADs were implemented with identical front-end-of-line (FEOL) structures, including the junction and guard-ring [...] Read more.
This paper presents a process-controlled study of illumination engineering in single-photon avalanche diodes (SPADs) fabricated in a 110 nm standard CMOS image sensor (CIS) technology. Front-illuminated (FI) and back-illuminated (BI) SPADs were implemented with identical front-end-of-line (FEOL) structures, including the junction and guard-ring configurations, enabling the isolation of the effects of illumination direction and back-end-of-line (BEOL) configuration without modifying the junction structure. Through TCAD simulations and comprehensive experimental characterizations, including current–voltage, light-emission, dark count rate (DCR), photon detection probability (PDP), and timing-jitter measurements, we systematically analyze the performance trade-offs introduced by the BI configuration. The BI SPAD exhibits enhanced near-infrared PDP and a broader spectral response due to its deeper absorption region and the incorporation of a metal reflector, while maintaining identical avalanche characteristics, as evidenced by an unchanged 72 ps full-width-at-half-maximum (FWHM) timing jitter. However, the backside illumination increases the diffusion tail, indicating a trade-off between near-infrared sensitivity and diffusion-related timing performance. These results provide design guidelines for optimizing SPAD performance through illumination-direction and BEOL engineering while preserving the FEOL design and demonstrate a useful approach for SPAD integration in standard CMOS technology. Full article
(This article belongs to the Special Issue Advances in Single Photon Detectors)
Show Figures

Figure 1

21 pages, 1233 KB  
Systematic Review
Single-Photon Detectors for Satellite and CubeSat Quantum Key Distribution: A Systematic Evidence Map
by Georgi Tsochev, Elitsa Gieva and Maria Nenova
Entropy 2026, 28(3), 295; https://doi.org/10.3390/e28030295 - 5 Mar 2026
Viewed by 483
Abstract
Advancing satellite and CubeSat quantum key distribution (QKD) requires receiver-level engineering trade studies, because secure-key feasibility in space is limited by single-photon detectors (SPDs) operating under SWaP, thermal, and radiation constraints. However, the question arises: does the literature provide sufficiently consistent evidence to [...] Read more.
Advancing satellite and CubeSat quantum key distribution (QKD) requires receiver-level engineering trade studies, because secure-key feasibility in space is limited by single-photon detectors (SPDs) operating under SWaP, thermal, and radiation constraints. However, the question arises: does the literature provide sufficiently consistent evidence to guide detector selection for space QKD? This systematic evidence map examines how recent research connects SNSPDs, Si SPAD/APD, InGaAs SPAD/APD, and NFAD variants to CubeSat QKD and space-based quantum communication links. To do so, a concept-token methodology identifies mission contexts and detector families through targeted keywords and key phrases, followed by structured extraction of detection efficiency η, dark count rate (DCR), timing jitter, receiver timing window Δt, operating mode, temperature/cooling, and radiation evidence. The results show an upward trend in publications, with many appearing in the last two years. SNSPDs and APD/SPAD families are most regularly discussed, yet key parameters—especially η, jitter, and explicit Δt—are reported unevenly, limiting cross-study comparability. CubeSat-tagged studies emphasize APD/SPAD feasibility and radiation-driven DCR evolution, while SNSPDs remain performance-leading but cryogenics-limited. Standardized reporting of η, DCR, jitter, Δt, temperature, and radiation conditions emerges as a practical avenue for accelerating deployable space-QKD receivers. Full article
(This article belongs to the Special Issue Space Quantum Communication)
Show Figures

Figure 1

21 pages, 5188 KB  
Article
A MATLAB-Based Simulation of Quantum Key Distribution Protocols at Telecom Wavelengths Under Various Realistic Conditions
by Vishal Sharma
Photonics 2026, 13(3), 234; https://doi.org/10.3390/photonics13030234 - 28 Feb 2026
Viewed by 463
Abstract
We investigate the feasibility of single and entangled photon-based quantum key distribution protocols at telecommunication wavelengths with two types of single photon detectors, namely InGaAs/InP and Silicon-APD, under various realistic conditions. The purpose of the current optical fiber-based simulation is to analyze the [...] Read more.
We investigate the feasibility of single and entangled photon-based quantum key distribution protocols at telecommunication wavelengths with two types of single photon detectors, namely InGaAs/InP and Silicon-APD, under various realistic conditions. The purpose of the current optical fiber-based simulation is to analyze the various performance parameters. In addition to these, we analyze the effect of possible attacks on the one and two weak decoy state protocols under investigation with the two deployed avalanche photodiodes. The simulation results obtained show that the one and two weak decoy states used in the entangled-based protocol at telecommunication wavelengths with considered attacks and under various industrial parameters outperforms the single photon-based quantum key distribution protocol. In addition, it is also observed that Silicon-APD (the avalanche photodiode) performs better than InGaAs/InP-APD when considering all the conditions. Full article
(This article belongs to the Special Issue Applications of Single-Photon Detector)
Show Figures

Figure 1

15 pages, 2995 KB  
Article
Thermal Drones Aid to Uncover Nocturnal Subgrouping Patterns of a Diurnal Primate
by Eduardo José Pinel-Ramos, Denise Spaan, Serge Wich and Filippo Aureli
Drones 2026, 10(2), 114; https://doi.org/10.3390/drones10020114 - 5 Feb 2026
Viewed by 751
Abstract
Spider monkeys (Ateles spp.) have traditionally been described as strictly diurnal primates, with only low levels of activity during the night. Consequently, little attention has been given to the possibility of nocturnal movements and social dynamics occurring at sleeping sites. Recent advances [...] Read more.
Spider monkeys (Ateles spp.) have traditionally been described as strictly diurnal primates, with only low levels of activity during the night. Consequently, little attention has been given to the possibility of nocturnal movements and social dynamics occurring at sleeping sites. Recent advances in technologies, such as drone-based thermal infrared imaging (TIR), provide new opportunities to explore behavioral patterns that were previously undetectable through ground-based observations. In this study, we aimed to evaluate whether Geoffroy’s spider monkeys (Ateles geoffroyi) change their subgroup size once they are at their sleeping sites by comparing the numbers of monkeys detected after sunset with those detected before sunrise using TIR drone surveys. We conducted TIR drone flights over four sleeping sites of well-habituated Geoffroy’s spider monkey groups in Los Árboles Tulum in the Yucatán Peninsula, Mexico. We carried out 18 flight pairs—18 flights at sunset when the majority of individual spider monkeys were expected to have arrived at the sleeping sites, and 18 flights the next following morning at sunrise—before the monkeys began their daily movements. Our results revealed that in 12 out of the 18 flight pairs (67%), the number of monkeys counted at sunset differed from the number counted at sunrise. In 58% of these 12 flight pairs, more monkeys were counted at sunrise than at sunset. Furthermore, when changes in subgroup size occurred, they were more frequent (67%) when the subgroups at sleeping sites were larger (>10 monkeys). These changes in subgroup size are consistent with the occurrence of fissions and fusions continuing after dark. This study provides preliminary evidence that Geoffroy’s spider monkeys are more active during the night than generally assumed. Furthermore, our results highlight the value of TIR drones as an effective tool for studying primate social dynamics under low-light conditions. Unlike traditional ground-based observations, which depend on natural light, TIR drones allow for accurate and reliable monitoring throughout the night. By providing access to behavioral information that would otherwise remain hidden, this technology opens new possibilities for understanding the full temporal range of activity of diurnal species. Full article
Show Figures

Figure 1

28 pages, 438 KB  
Article
Holographic Naturalness and Information See-Saw Mechanism for Neutrinos
by Andrea Addazi and Giuseppe Meluccio
Particles 2026, 9(1), 11; https://doi.org/10.3390/particles9010011 - 2 Feb 2026
Viewed by 608
Abstract
The microscopic origin of the de Sitter entropy remains a central puzzle in quantum gravity that is related to the cosmological constant problem. Within the paradigm of Holographic Naturalness, we propose that this entropy is carried by a vast number of [...] Read more.
The microscopic origin of the de Sitter entropy remains a central puzzle in quantum gravity that is related to the cosmological constant problem. Within the paradigm of Holographic Naturalness, we propose that this entropy is carried by a vast number of light, coherent degrees of freedom—called “hairons”—which emerge as the moduli of gravitational instantons on orbifolds. Starting from the Euclidean de Sitter instanton (S4), we construct a new class of orbifold gravitational instantons, S4/ZN, where N corresponds to the de Sitter entropy. We demonstrate that the dimension of the moduli space of these instantons scales linearly with N, and we identify these moduli with the hairon fields. A ZN symmetry, derived from Wilson loops in the instanton background, ensures the distinguishability of these modes, leading to the correct entropy count. The hairons acquire a mass of the order of the Hubble scale and exhibit negligible mutual interactions, suggesting that the de Sitter vacuum is a coherent state, or Bose–Einstein condensate, of these fundamental excitations. Then, we present a novel framework which unifies neutrino mass generation with the cosmological constant through gravitational topology and holography. The small neutrino mass scale emerges naturally from first principles, without requiring new physics beyond the Standard Model and Gravity. The gravitational Chern–Simons structure and its anomaly with neutrinos force a topological Higgs mechanism, leading to neutrino condensation via S4/ZN gravitational instantons. The number of topological degrees of freedom NMP2/Λ10120 provides both the holographic counting of the de Sitter entropy and a 1/Ninformation see-saw mechanism for neutrino masses. Our framework makes the following predictions: (i) a neutrino superfluid condensation forming Cooper pairs below meV energies, as a viable candidate for cold dark matter; (ii) a possible resolution of the strong CP problem through a QCD composite axion state; (iii) time-varying neutrino masses which track the evolution of dark energy; and (iv) several distinctive signatures in astroparticle physics, ultra-high-energy cosmic rays and high magnetic field experiments. Full article
20 pages, 8055 KB  
Article
Research on an Underwater Visual Enhancement Method Based on Adaptive Parameter Optimization in a Multi-Operator Framework
by Zhiyong Yang, Shengze Yang, Yuxuan Fu and Hao Jiang
Sensors 2026, 26(2), 668; https://doi.org/10.3390/s26020668 - 19 Jan 2026
Viewed by 342
Abstract
Underwater images often suffer from luminance attenuation, structural degradation, and color distortion due to light absorption and scattering in water. The variations in illumination and color distribution across different water bodies further increase the uncertainty of these degradations, making traditional enhancement methods that [...] Read more.
Underwater images often suffer from luminance attenuation, structural degradation, and color distortion due to light absorption and scattering in water. The variations in illumination and color distribution across different water bodies further increase the uncertainty of these degradations, making traditional enhancement methods that rely on fixed parameters, such as underwater dark channel prior (UDCP) and histogram equalization (HE), unstable in such scenarios. To address these challenges, this paper proposes a multi-operator underwater image enhancement framework with adaptive parameter optimization. To achieve luminance compensation, structural detail enhancement, and color restoration, a collaborative enhancement pipeline was constructed using contrast-limited adaptive histogram equalization (CLAHE) with highlight protection, texture-gated and threshold-constrained unsharp masking (USM), and mild saturation compensation. Building upon this pipeline, an adaptive multi-operator parameter optimization strategy was developed, where a unified scoring function jointly considers feature gains, geometric consistency of feature matches, image quality metrics, and latency constraints to dynamically adjust the CLAHE clip limit, USM gain, and Gaussian scale under varying water conditions. Subjective visual comparisons and quantitative experiments were conducted on several public underwater datasets. Compared with conventional enhancement methods, the proposed approach achieved superior structural clarity and natural color appearance on the EUVP and UIEB datasets, and obtained higher quality metrics on the RUIE dataset (Average Gradient (AG) = 0.5922, Underwater Image Quality Measure (UIQM) = 2.095). On the UVE38K dataset, the proposed adaptive optimization method improved the oriented FAST and rotated BRIEF (ORB) feature counts by 12.5%, inlier matches by 9.3%, and UIQM by 3.9% over the fixed-parameter baseline, while the adjacent-frame matching visualization and stability metrics such as inlier ratio further verified the geometric consistency and temporal stability of the enhanced features. Full article
(This article belongs to the Section Sensing and Imaging)
Show Figures

Figure 1

20 pages, 2964 KB  
Article
Correlating Scanning Electron Microscopy and Raman Microscopy to Quantify Occupational Exposure to Micro- and Nanoscale Plastics in Textile Manufacturing
by Dirk Broßell, Emilia Visileanu, Catalin Grosu, Asmus Meyer-Plath and Maike Stange
Pollutants 2026, 6(1), 6; https://doi.org/10.3390/pollutants6010006 - 13 Jan 2026
Viewed by 852
Abstract
Airborne micro- and nanoplastic particles (MNPs) are increasingly recognized as a potential occupational exposure hazard, yet substance-specific workplace data remain limited. This study quantified airborne MNP concentrations during polyester microfiber production using a correlative SEM–Raman approach that enabled chemical identification and size-resolved particle [...] Read more.
Airborne micro- and nanoplastic particles (MNPs) are increasingly recognized as a potential occupational exposure hazard, yet substance-specific workplace data remain limited. This study quantified airborne MNP concentrations during polyester microfiber production using a correlative SEM–Raman approach that enabled chemical identification and size-resolved particle characterization. The aerosol mixture at the workplace was dominated by sub-micrometer particles, with PET—handled onsite—representing the main process-related MNP type, and black tire rubber (BTR) forming a substantial background contribution. Across both sampling periods, total MNP particle number concentrations ranged between 6.2 × 105 and 1.2 × 106 particles/m3, indicating consistently high particle counts. In contrast, estimated MNP-related mass concentrations were much lower, with PM10 levels of 12–15 µg/m3 and PM2.5 levels of 1.3–1.6 µg/m3, remaining well below applicable occupational exposure limits and near or below 8 h-equivalent WHO guideline values. Comparison with earlier workplace and indoor studies suggests that previously reported concentrations were likely underestimated due to sampling strategies with low efficiency for small particles. Moreover, real-time optical measurements substantially underestimated particle number and mass in this study, reflecting their limited suitability for aerosols dominated by small or dark particles. Overall, the data show that workplace MNP exposure at the investigated site is driven primarily by very small particles present in high numbers but low mass. The findings underscore the need for substance-specific, size-resolved analytical approaches to adequately assess airborne MNP exposure and to support future development of MNP-relevant occupational health guidelines. Full article
(This article belongs to the Section Air Pollution)
Show Figures

Graphical abstract

10 pages, 501 KB  
Article
Simulation of a SiPM-Based Cherenkov Camera
by Isaac Buckland, Riccardo Munini and Valentina Scotti
Particles 2025, 8(4), 96; https://doi.org/10.3390/particles8040096 - 3 Dec 2025
Cited by 1 | Viewed by 564
Abstract
Future space detectors for Ultra High Energy neutrinos and cosmic rays will utilize Cherenkov telescopes to detect forward-beamed Cherenkov light produced by charged particles in Extensive Air Showers (EASs). A Cherenkov detector can be equipped with an array of Silicon Photo-Multiplier (SiPM) pixels, [...] Read more.
Future space detectors for Ultra High Energy neutrinos and cosmic rays will utilize Cherenkov telescopes to detect forward-beamed Cherenkov light produced by charged particles in Extensive Air Showers (EASs). A Cherenkov detector can be equipped with an array of Silicon Photo-Multiplier (SiPM) pixels, which offer several advantages over traditional Photo-Multiplier Tubes (PMTs). SiPMs are compact and lightweight and operate at lower voltages, making them well-suited for space-based experiments. The SiSMUV (SiPM-based Space Monitor for UV-light) is developing a SiPM-based Cherenkov camera for PBR (POEMMA Baloon with Radio) at INFN Napoli. To understand the response of such an instrument, a comprehensive simulation of the response of individual SiPM pixels to incident light is needed. For the accurate simulation of a threshold trigger, this simulation must reproduce the current produced by a SiPM pixel as a function of time. Since a SiPM pixel is made of many individual Avalanche Photo-Diodes (APDs), saturation and pileup in APDs must also be simulated. A Gaussian mixture fit to ADC count spectrum of a SiPM pixel exposed to low levels of laser light at INFN Napoli shows a significant amount of samples between the expected PE (Photo Electron) peaks. Thus, noise sources such as dark counts and afterpulses, which result in partially integrated APD pulses, must be accounted for. With static, reasonable values for noise rates, the simulation chain presented in this work uses the characteristics of individual APDs to produce the aggregate current produced by a SiPM pixel. When many such pulses are simulated and integrated, the ADC spectra generated by low levels of laser light at the INFN Napoli SiSMUV test setup can be accurately reproduced. Full article
Show Figures

Figure 1

24 pages, 6057 KB  
Article
The Metabolism of Streptomyces avermitilis Isolated from Agricultural Soils During the Four Seasons of the Year
by Janet Leandro Marmolejo, María Magdalena Crosby Galván, Elsa Margarita Crosby Galván, Laura Haydée Vallejo Hernández, María Teresa Sánchez-Torres Esqueda, César Cortez Romero and Ricardo Daniel Améndola Massiotti
Appl. Microbiol. 2025, 5(4), 138; https://doi.org/10.3390/applmicrobiol5040138 - 27 Nov 2025
Viewed by 1249
Abstract
Streptomyces avermitilis is a soil actinobacterium and has a complex metabolism in its natural habitat. Because of this, the environmental fluctuations present in the seasons can activate or silence the biosynthetic pathways involved in its metabolism. The objective of this research was to [...] Read more.
Streptomyces avermitilis is a soil actinobacterium and has a complex metabolism in its natural habitat. Because of this, the environmental fluctuations present in the seasons can activate or silence the biosynthetic pathways involved in its metabolism. The objective of this research was to analyze the morphological characteristics of the metabolism of Streptomyces avermitilis, isolated during the four seasons of the year and from four types of soil. Isolation was performed on oat agar ISP-3 and nystatin as an antifungal agent. The planting methods were rod drag and cross striations. The Petri dishes were incubated for 10 days at 30 °C in complete darkness. For 10 days, a colony count was performed to analyze the growth curves, as was an evaluation of the diffusible pigments in each Petri dish. The isolates presented the diffusible pigments white, yellow, orange, red and pink with a higher proportion in spring and summer compared to in autumn and winter. Under laboratory conditions, the isolates in summer presented the three phases of bacterial growth: lag (24 h), exponential (48–96 h) and stationary (120–168 h). A doubling time of 35.30–62.92 h was obtained. The morphological characteristics of the metabolism of Streptomyces avermitilis show differences according to the climatic conditions of each season of the year. Full article
(This article belongs to the Topic Microbial Cell Factories for Natural Products)
Show Figures

Figure 1

27 pages, 5439 KB  
Article
320 × 240 SPAD Direct Time-of-Flight Image Sensor and Camera Based on In-Pixel Correlation and Switched-Capacitor Averaging
by Maarten Kuijk, Ayman Morsy, Thomas Lapauw, Thomas Van den Dries, Wannes Nevens, Mohamed A. Bounouar, Hans Ingelberts and Daniel Van Nieuwenhove
Sensors 2025, 25(21), 6772; https://doi.org/10.3390/s25216772 - 5 Nov 2025
Cited by 1 | Viewed by 2273
Abstract
Correlation-Assisted Direct Time-of-Flight (CA-dToF) is demonstrated for the first time on a large 320 × 240-pixel SPAD array sensor that includes on-chip high-speed timing support circuitry. SPAD events are processed in-pixel, avoiding data communication over the array and/or storage bottlenecks. This is accomplished [...] Read more.
Correlation-Assisted Direct Time-of-Flight (CA-dToF) is demonstrated for the first time on a large 320 × 240-pixel SPAD array sensor that includes on-chip high-speed timing support circuitry. SPAD events are processed in-pixel, avoiding data communication over the array and/or storage bottlenecks. This is accomplished by sampling two orthogonal triangle waves that are synchronized with short light pulses illuminating the scene. Using small switched-capacitor circuits, exponential moving averaging (EMA) is applied to the sampled voltages, delivering two analog voltages (VQ2, VI2). These contain the phase delay, or the time of flight between the light pulse and photon’s time of arrival (ToA). Uncorrelated ambient photons and dark counts are averaged out, leaving only their associated shot noise impacting the phase precision. The QVGA camera allows for capturing depth-sense images with sub-cm precision over a 6 m range of detection, even with a small PDE of 0.7% at an 850 nm wavelength. Full article
Show Figures

Figure 1

15 pages, 279 KB  
Article
The Effect of Storage Time on the Quality of Low-Sugar Apple Jams with Steviol Glycosides
by Marlena Pielak and Ewa Czarniecka-Skubina
Foods 2025, 14(21), 3678; https://doi.org/10.3390/foods14213678 - 28 Oct 2025
Viewed by 1182
Abstract
This study investigated the effect of storage time on the quality of low-sugar apple jams partially substituted with steviol glycosides (SGs). Apple jams were prepared with 0%, 10%, 20%, 30%, and 40% sugar replacement using highly purified SGs (95.1%). The jams were evaluated [...] Read more.
This study investigated the effect of storage time on the quality of low-sugar apple jams partially substituted with steviol glycosides (SGs). Apple jams were prepared with 0%, 10%, 20%, 30%, and 40% sugar replacement using highly purified SGs (95.1%). The jams were evaluated immediately after production and after 3 and 6 months of storage at 22 °C in the dark. Physicochemical analyses included dry matter, total soluble solids, vitamin C, total ash, pH, titratable acidity, malic acid, and color parameters (L*, a*, b*). Sensory and microbiological assessments were also carried out. During storage, the dry matter content significantly decreased from 41.4% (control) to 35.6% (40% SGs), while titratable acidity increased from 10.69° to 16.73° (p < 0.05), and pH values remained stable (3.15–3.29). Vitamin C content decreased significantly (from 0.56 mg/100 g to 0.19 mg/100 g; 33–66% degradation). The color of jams became lighter with increasing SG substitution (L* increased from 17.19 to 24.73; ΔE up to 9.66) and slightly darkened after storage (ΔL ≈ −1.0). Microbiological analysis confirmed complete safety, with total colony counts < 10 CFU/g and no presence of Listeria monocytogenes or coagulase-positive Staphylococcus. Sensory evaluation by a trained panel (10 assessors, aged 34–56 years, with similar training in fruit and vegetable preserve evaluation) showed that jams with 10–30% SG substitution maintained desirable apple aroma and sweetness, whereas higher SG levels enhanced metallic odor (0.12–0.95 c.u.) and bitterness (0.2–1.9 c.u.) while slightly reducing apple flavor intensity (p < 0.05). Despite these differences, all jams remained acceptable after 6 months of storage. Overall, replacing up to 40% of sucrose with steviol glycosides provided microbiological stability, controlled color changes, and acceptable sensory quality, supporting the production of low-sugar jams in line with clean-label and sustainability trends in modern food technology. Full article
(This article belongs to the Special Issue Storage and Shelf-Life Assessment of Food Products: 2nd Edition)
19 pages, 1763 KB  
Article
Hypericin Photodynamic Therapy Induces Cytotoxicity and Modulates Cytokine Secretion in MCF-7 Breast Cancer Cells
by Magdalena Czarnecka-Czapczyńska, Zenon Czuba, David Aebisher, Wiktoria Mytych, Jakub Fiegler-Rudol, Rafał Wiench and Aleksandra Kawczyk-Krupka
J. Clin. Med. 2025, 14(21), 7514; https://doi.org/10.3390/jcm14217514 - 23 Oct 2025
Viewed by 1087
Abstract
Background/Aim: Photodynamic therapy uses a photosensitizer and light to generate reactive oxygen species that kill tumor cells and can shift inflammatory signaling. Hypericin is a potent photosensitizer, but its immunomodulatory impact in breast cancer needs clarification. We evaluated the phototoxic and cytokine-modulating [...] Read more.
Background/Aim: Photodynamic therapy uses a photosensitizer and light to generate reactive oxygen species that kill tumor cells and can shift inflammatory signaling. Hypericin is a potent photosensitizer, but its immunomodulatory impact in breast cancer needs clarification. We evaluated the phototoxic and cytokine-modulating effects of hypericin-mediated photodynamic therapy in MCF-7 human breast adenocarcinoma cells. This study examines how HYP-PDT affects MCF-7 breast cancer cells by assessing viability and cytokine secretion to guide the development of targeted, immune-enhancing PDT protocols. Methods: MCF-7 cells were incubated with hypericin at 0, 0.125, 0.25, 0.5, or 1 μM, then exposed to light doses of 0, 1, 2, or 5 J/cm2. Viability was measured 24 h later by MTT; selected conditions were also assessed by Trypan Blue. Cell supernatants collected after sublethal treatment were analyzed for IL-6, IL-8, IL-10, and TNF-α using a multiplex immunoassay. Experiments were repeated four times. Statistical analyses followed the study’s plan for group comparisons. Results: At 1 J/cm2, MTT values did not differ from matched dark controls across hypericin concentrations. At 2 and 5 J/cm2, some conditions showed increased MTT signal relative to controls, indicating higher metabolic activity; Trypan Blue performed at 0 J/cm2 showed a concentration-dependent reduction in viability with hypericin. Hypericin-PDT decreased IL-6 and IL-8 concentrations and increased TNF-α in MCF-7 supernatants. No statistically significant changes were detected for IL-10. Conclusions: Hypericin-PDT altered inflammatory readouts in MCF-7 cells, with reductions in IL-6 and IL-8 and an increase in TNF-α, consistent with a pro-inflammatory shift. Viability results suggest condition-dependent changes in metabolic activity or survival effects that warrant confirmation with matched cell counts across all light doses. These findings support further standardized dosimetry and multi-line validation of hypericin-PDT in breast cancer models. Full article
(This article belongs to the Section Oncology)
Show Figures

Figure 1

Back to TopTop