Search Results (178)

Formamidinium lead bromide (FAPbBr₃) quantum dots (QDs) have shown potential in light-emitting diodes (LEDs). However, their performance is constrained by surface defects and the limitations of charge transport. Zwitterionic ligands, owing to their twin functions of Lewis base coordination and electrostatic compensation, passivate surface defects of perovskite QDs. Some other zwitterionic ligands are high-cost, while amino acids, as zwitterionic ligands, are inexpensive, readily available, and have efficient passivation capabilities. Their short main chain and programmable side chain can control the volume and dipole at Å-scale range through functional group selection and feed ratio regulation, achieving interface energy level engineering. This work adopts green-emitting FAPbBr₃ QDs as the model, tuning ligand properties by modifying side-chain functional groups, thereby achieving PLQY of 87.2%. Experimental results and DFT reveal that amino acids preferentially undergo coordination and can be further fine-tuned through conjugated contacts. Without severe site competition and without affecting coordination occupation and ligand uniformity, the EQE reaches 5.6% and the luminance exceeds 9000 cd/m². This low-cost technology is easily scalable and broadly manufacturable, providing a replicable material and interface design route for green zone perovskite LEDs. Full article

Biomass of the plumose anemone Metridium senile has surged in the benthic ecosystem of the North Yellow Sea in recent years. Understanding its diet and the proportional contributions of food sources is essential for assessing the ecological consequences of this expansion. The species is often characterized as a passive suspension feeder, yet laboratory feeding trials have documented shrimp consumption. Because prior dietary information from the region is scarce, conventional stable isotope approaches are poorly constrained. We developed an integrative framework coupling trophic position estimation, isotopic niche metrics, spatial point pattern analysis, and a Bayesian mixing model to improve diet attribution under limited prior information and to test whether M. senile preys on small-bodied and juvenile teleosts and invertebrates under natural conditions. Our analyses showed that: (i) M. senile occupied a high trophic position (TP = 3.09 ± 0.25), exceeding those estimated for putative predators in our dataset, implying weak top-down control; (ii) in isotopic niche analyses, M. senile showed high posterior probabilities of occurring within the niches of cephalopods and medium-sized fishes (78.30% and 63.04%, respectively), consistent with shared prey and inconsistent with a strictly suspension-feeding strategy; (iii) mixing space diagnostics informed by spatial point pattern analysis indicated that including small-sized fishes and shrimps as sources was necessary to reconcile the elevated TP; and (iv) the Bayesian mixing model estimated that small-bodied and juvenile teleosts and invertebrates supplied most long-term nutrition (posterior mean ≈ 0.65), with the remainder from suspension-derived sources, consistent with an opportunistic generalist rather than a strict suspension feeder. Sustained predation on small-bodied and juvenile teleosts and invertebrates could suppress early fish recruitment, impose top-down control on forage species, and alter the local food web structure. Management should monitor M. senile (size structure, population density, and co-occurrence with juveniles and forage biota) and consider targeted removals and seafloor litter cleanups in priority habitats. The framework is applicable to diet studies with limited prior information; adding δ³⁴S, compound-specific amino-acid isotopes (CSIA-AA), and DNA-based dietary evidence should further sharpen source discrimination. Full article

Improving the efficiency, economic viability, and environmental sustainability of beef cattle production requires tools to identify resource-efficient animals. Validated tools to measure, monitor, and verify individual feed and water intake are needed. Here, we verify the validity of the Vytelle In-Pen Weighing Position to passively collect daily full body weights and assess the use of an integrated flow meter with a commercial waterer as a tool to measure daily water intake. This study involved 103 bulls (40 Charolais and 63 Angus) and 54 heifers (25 Charolais and 29 Angus). These animals were fed in a facility with feed intake nodes, In-Pen Weighing, and metered waterers. Body weights collected on the chute scale and total water usage measured by a residential water meter were used to evaluate body weight and water intake measured at the In-Pen Weighing Positions. We confirmed that In-Pen Weighing is highly correlated to chute weighing (Spearman’s correlation coefficient, ρ = 0.99, p < 0.0001). We observed high correlation of total water use measured at the In-Pen Weighing units with the facility’s total water use (ρ = 0.9999, p < 0.0001). This validates the accuracy of the in-pen water meters, but not the precision of applying water consumption to individual animals. The use of such passive monitoring equipment has the potential to help improve the sustainability of animal agriculture. Full article

Distribution networks are facing increasing challenges due to the growing share of renewable energy sources (RESs), particularly because of the volatile nature of the available power. In addition to targeted grid expansion measures, the concept of a dynamic grid topology offers an additional layer of flexibility in the power system. Furthermore, there are concepts to use active coupling methods in distribution grids, such as medium-voltage direct current (MVDC) systems, which enable horizontal power flows between distribution grids and thus active control. This paper investigates the potential of combining dynamic passive and active coupling between two distribution grids. Particle swarm optimization (PSO) is used to determine both an optimized operating point of two MVDC interconnections as well as the most efficient switch configuration within both networks. The goal of the optimization is to reduce both network losses and power exchange between the different voltage levels. To evaluate its potential, various use cases are simulated using a representative feed-in of photovoltaics while considering grid constraints. Individual and combined impacts of dynamic AC switching and DC coupling are compared using a modified IEEE-123 test feeder. The results show a significant optimization potential, especially with an increase in RES penetration within the grid. In the best scenarios, the power losses can be decreased by 33.73% and the power transfer can be reduced by 8.75%. Full article

Among other uses, DC-DC converters are employed in the auxiliary power modules (APMs) of electric vehicles (EVs), connecting the high-voltage traction battery to the low-voltage auxiliary system (AS). Traditionally, the APM is an isolated two-port, two-level (2L) DC-DC converter, and the auxiliary loads are fed at a fixed voltage level, e.g., 12 V in passenger cars. Dual-active-bridge (DAB) converters are commonly used for this application, as they provide galvanic isolation, high power density and efficiency, and bidirectional power flow capability. However, the auxiliary loads do not present a uniform optimum supply voltage, hindering overall efficiency. Thus, a more flexible approach, providing multiple supply voltages, would be more suitable for this application. Multiport DC-DC converters capable of feeding auxiliary loads at different voltage levels are a promising alternative. Multilevel neutral-point-clamped (NPC) DAB converters offer several advantages compared to conventional two-level (2L) ones, such as greater efficiency, reduced voltage stress, and enhanced scalability. The series connection of the NPC DC-link capacitors enables a multiport configuration without additional conversion stages. Moreover, the modular nature of the ML NPC DAB converter enables scalability while using semiconductors with the same voltage rating and without requiring additional passive components, thereby enhancing the converter’s power density and efficiency. This paper proposes a modulation strategy and decoupled closed-loop control strategy for the generalized multiport 2L-NL NPC DAB converter interfacing the EV traction battery with the AS, and its performance is validated through hardware-in-the-loop testing and simulations. The proposed modulation strategy minimizes conduction losses in the converter, and the control strategy effectively regulates the LV battery modules’ states of charge (SoC) by varying the required SoC and the power sunk by the LV loads, with the system stabilizing in less than 0.5 s in both scenarios. Full article

As many German SMEs approach the end of their photovoltaic (PV) feed-in tariff period, the challenge of maintaining economic viability for these installations intensifies. This study addresses the integration of intermittent renewable energy sources (iRES) into production processes by proposing a method to identify and exploit industrial flexibility. A detailed case study of a German carpentry factory designed as a Net-Zero Energy Factory (NZEF) illustrates the approach, combining energy monitoring with blockchain technology to enhance transparency and traceability. Flexibility is exploited through a three-layer control system involving passive operator guidance, battery storage, and electric vehicle charging. The installation of a 40 kWh battery raises self-consumption from 50 to 70%, saving approximately EUR 4270 annually. However, this alone does not offset the investment. Blockchain-based transparency adds economic value by enabling premium pricing, potentially increasing revenue by up to 10%. This dual benefit supports the financial case for NZEFs. The framework is replicable and particularly relevant for low-automation industries, offering small and medium enterprises (SMEs) a viable pathway to decarbonization. The results align with the European Clean Industrial Deal, demonstrating how digitalization and industrial flexibility can reinforce competitiveness, sustainability, and digital trust in Europe’s transition to a resilient, low-carbon economy. Full article

Most research on domestic dog (Canis familiaris) behavior has focused on pets with restricted movement. However, free-ranging dogs exist in diverse cultural contexts globally, and their interactions with humans are less understood. Tourists can facilitate unrestricted dog movement into wilderness areas, where they may negatively impact wildlife. This study investigated which stimuli—namely, voice, touch, or food—along with inherent factors (age, sex, sociability) motivate free-ranging dogs to follow a human stranger. We measured the distance (up to 600 m) of 129 free-ranging owned and stray dogs from three villages in southern Chile as they followed an experimenter who presented them one of the above stimuli or none (control). To evaluate the effect of dog sociability (i.e., positive versus stress-related or passive behaviors), we performed a 30 s socialization test (standing near the dog without interacting) before presenting a 10 s stimulus twice. We also tracked whether the dog was in the company of other dogs. Each focus dog was video-recorded and tested up to three times over five days. Generalized linear mixed-effects models revealed that the food stimulus significantly influenced dogs’ motivation to follow a stranger, as well as a high proportion of sociable behaviors directed towards humans and the company of other dogs present during the experiment. Juveniles tended to follow a stranger more than adults or seniors, but no effects were found for the dog’s sex, whether an owner was present, the repetition of trials, the location where the study was performed, or for individuals as a random variable. This research highlights that sociability as an inherent factor shapes dog–stranger interactions in free-ranging dogs when food is given. In the context of wildlife conservation, we recommend that managers promote awareness among local communities and tourists to avoid feeding dogs, especially in the context of outdoor activities close to wilderness. Full article

Millimeter-wave frequencies are crucial for meeting the high-capacity, low-latency demands of 5G communication systems, thereby driving the need for compact, high-gain antenna arrays capable of efficient beamforming. This paper presents the design, simulation, fabrication, and experimental validation of a compact, high-efficiency 1 × 6 linear series-fed microstrip patch antenna array for 5G millimeter-wave communication operating at 28 GHz. The proposed antenna is fabricated on a low-loss Rogers RO3003 substrate and incorporates an integrated symmetric two-way microstrip power divider to ensure balanced feeding and phase uniformity across elements. The antenna achieves a simulated peak gain of 11.5 dBi and a broad simulated impedance bandwidth of 30.21%, with measured results confirming strong impedance matching and a return loss better than −20 dB. The far-field radiation patterns demonstrate a narrow, highly directive beam in the E-plane, and the H-plane results reveal beam tilting behavior, validating the antenna’s capability for passive beam steering through feedline geometry and element spacing (~0.5λ). Surface current distribution analysis confirms uniform excitation and efficient radiation, further validating the design’s stability. The fabricated prototype shows excellent agreement with the simulation, with minor discrepancies attributed to fabrication tolerances. These results establish the proposed antenna as a promising candidate for applications requiring compact, high-gain, and beam-steerable solutions, such as 5G mm-wave wireless communication systems, point-to-point wireless backhaul, and automotive radar sensing. Full article

Recent advances in passive acoustic monitoring (PAM) have markedly improved the ability to study marine soundscapes by enabling long-term, non-invasive monitoring of biological sounds across large spatial and temporal scales. Among aquatic organisms, fish are primary contributors to biophony, producing sounds associated with feeding, reproduction, and social behavior. However, the majority of previous research has focused on individual vocalizations, with limited attention to collective acoustic phenomena such as fish choruses. This study quantitatively analyzes choruses produced by the small yellow croaker (Larimichthys polyactis), an ecologically and commercially important species in the Northwest Pacific Ocean. Using power spectral density (PSD) analysis, we examined long-term underwater recordings from a sea cage containing approximately 2000 adult small yellow croakers. The choruses were centered around ~600 Hz and exhibited sound pressure levels 15–20 dB higher at night than during the day. These findings highlight the ecological relevance of fish choruses and support their potential use as indicators of biological activity. This study lays the foundation for incorporating fish choruses into soundscape-based PAM frameworks to enhance biodiversity and habitat monitoring. Full article

This article proposes a nonlinear control strategy to address the voltage instability issue caused by the boost converter with an uncertain constant power load (CPL). This strategy combines a passivity-based controller (PBC) with a virtual DC motor controller (VDCM). Initially, a PBC is designed for the boost converter, which enhances the robustness of the converter with CPL perturbations in the DC bus voltage. To overcome the limitations of PBC, including steady-state errors resulting from variations in load or input voltage, the VDCM is incorporated, simulating the characteristics of a DC motor. This addition improves the system’s inertia and damping, making it more stable and significantly enhancing its dynamic performance. The efficacy and stability analysis of the proposed control strategy is validated through both simulation and experimentation. Full article

In recent years, passive acoustic monitoring (PAM) technology has significantly contributed to advancements in aquaculture techniques, system iterations, and increased production yields within intelligent feeding systems for Penaeus vannamei. However, current PAM-based intelligent feeding systems do not incorporate environmental factors into the decision process, limiting the improvement of monitoring accuracy in complex environments such as ponds. To establish a connection between environmental factors and the feeding acoustics of P. vannamei, this study utilized PAM technology combined with video analysis to investigate the effects of three key environmental factors—temperature, ammonia nitrogen, and nitrite nitrogen—on the feeding behavioral characteristics of shrimp, with a specific focus on acoustic signals “clicks”. The results demonstrated a significant correlation between the number of clicks and feed consumption in shrimp across different treatments, establishing this stable relationship as a reliable indicator for assessing shrimp feeding status. When water temperature increased from 20 °C to 32 °C, shrimp feed consumption showed an elevation from 0.46 g to 0.95 g per 30 min, with the average number of clicks increasing from 388 to 2947.58 and sound pressure levels rising accordingly. Conversely, ammonia nitrogen at 12 mg/L reduced feed consumption by 0.15 g and decreased click counts by 911.75 pulses compared to controls, while nitrite nitrogen at 40 mg/L similarly suppressed feed consumption by 0.15 g and the average number of clicks by 304.75. A rise in water temperature stimulated shrimp behaviors such as feeding, swimming, and foraging, while elevated concentrations of ammonia nitrogen and nitrite nitrogen significantly inhibited shrimp activity. Redundancy analysis revealed that temperature was the most prominent factor among the three environmental factors influencing shrimp feeding. This study is the first to quantify the specific effects of common environmental factors on the acoustic feeding signals and feeding behavior of P. vannamei using PAM technology. It confirms the feasibility of using PAM technology to assess shrimp feeding conditions under diverse environmental conditions and the necessity of integrating environmental monitoring modules into future feeding systems. This study provides behavioral evidence for the development of precise feeding technologies and the upgrade of intelligent feeding systems for P. vannamei. Full article

Neonatal calves possess an immature and naïve immune system and are reliant on the intake of maternal colostrum for the passive transfer of immunoglobulins. Maternal antibodies delivered to the calf via colostrum, are crucial to prevent calfhood diseases and death. Failure of transfer of passive immunity (FTPI) is a condition in which calves do not acquire enough maternal antibodies, mostly in the form of IgG, due to inadequate colostrum quality or delayed colostrum feeding. The diagnosis and risk factors for FTPI have been widely studied in dairy cattle; however, in beef calves, the research interest in the topic is relatively recent, and the most adequate diagnostic and preventative methods are still in development, making it difficult to define recommendations for the assessment and prevention of FTPI in cow–calf operations. The objective of this scoping review is to identify the published literature on best practices for colostrum management and transfer of passive immunity (TPI) in neonatal beef calves. The literature was searched using three electronic databases (CAB Direct, Scopus, and PubMed) for publications from 2003 to 2025. The search process was performed during the period from May to July 2023, and was repeated in January 2025. All screening processes were performed using Covidence systematic review software (Veritas Health Innovation, Melbourne, Australia). A total of 800 studies were initially identified through database searches. After removing duplicates, 346 studies were screened based on their titles and abstracts, leading to the exclusion of 260 studies. The remaining 86 studies underwent full-text screening, and 58 studies were considered eligible for data extraction. Hand-searching the references from published review papers on the subject yielded an additional five studies, bringing the total to 63 included articles. The prevalence of FTPI has been estimated to be between 5.8% and 34.5% in beef calves. Factors studied related to colostrum management include quality and quantity of colostrum intake, the timing and method of colostrum feeding, and the microbial content of the colostrum. Studies on risk factors related to the calf include the topics calf sex, twin status, calf vigor, weight, month of birth, cortisol and epinephrine concentrations, and the administration of nonsteroidal anti-inflammatory drugs to calves after difficult calving. The dam-related risk factors studied include dam body condition score and udder conformation, breed, parity, genetics, prepartum vaccinations and nutrition, calving area and difficulty, and the administration of nonsteroidal anti-inflammatory drugs at C-section. Most importantly for beef systems, calves with low vigor and a weak suckling reflex are at high risk for FTPI; therefore, these calves should be given extra attention to ensure an adequate consumption of colostrum. While serum IgG levels of < 8 g/L or < 10 g/L have been suggested as cutoffs for the diagnosis of FTPI, 16 g/L and 24 g/L have emerged as cutoffs for adequate and optimal serum IgG levels in beef calves. Several field-ready diagnostics have been compared in various studies to the reference standards for measuring indicators of TPI in beef calves, where results often differ between models or manufacturers. Therefore, care must be taken when interpreting these results. Full article

Background: Neonatal influenza is a rare condition. Young infants have immature immune defenses and are unable to receive direct vaccination; this can result in significant illness. Maternal anti-influenza immunization during pregnancy provides passive antibodies to the newborn via transplacental transfer, significantly decreasing the incidence and severity of influenza in early infancy. Nevertheless, the vaccination coverage during pregnancy remains low in many regions, leaving certain neonates without adequate protection. Methods: We present three cases of laboratory-confirmed influenza infection in neonates admitted to the “Sf. Ioan” Clinical Emergency Pediatric Hospital in Galați and conduct a literature review. The clinical presentation, co-infections, timing of antiviral therapy, laboratory findings, maternal vaccination status, and outcomes (including the hospitalization duration and recovery) were systematically analyzed for each case. Results: All three neonates were full-term and previously healthy, born to mothers who had not received influenza vaccinations during their pregnancies. They presented at ages ranging from 2 to 4 weeks with fever, respiratory symptoms including a cough, nasal congestion, and respiratory distress, as well as feeding difficulties. One case involved a co-infection with Bordetella pertussis, which manifested as a severe paroxysmal cough, cyanosis, and apnea. Laboratory findings in the cases with influenza alone indicated leukopenia accompanied by normal C-reactive protein levels. In the co-infection case, leukocytosis, lymphocytosis, and thrombocytosis were observed. All the infants received oseltamivir treatment within 48 h of the symptom onset; the case with pertussis co-infection also received azithromycin. Each infant required supplemental oxygen, but none necessitated mechanical ventilation. Clinical improvement was observed in all cases, with hospitalization ranging from 6 to 7 days and complete recovery without complications. Conclusions: Neonatal influenza may result in considerable morbidity, particularly in infants born to unvaccinated mothers. Positive outcomes, however, have been correlated with early diagnosis and antiviral treatment. Pertussis co-infection may exacerbate clinical progression, underscoring the importance of maternal immunization against both influenza and pertussis. In this case series, we aim to present three cases of laboratory-confirmed influenza in neonates born to mothers who were not immunized against influenza during pregnancy. These cases highlight the clinical presentations of neonatal influenza, underscore the risks associated with pertussis co-infection, and reinforce the importance of maternal influenza and Tdap vaccination for preventing severe outcomes in newborns. Full article

This article considers the study of the grinding and homogeneity of a feed mixture in a device that combines the processes of grinding and mixing. It was found that it is important to improve the working elements with the elimination of passive zones. In this regard, the purpose of this study is to improve the working elements of the feed preparation device with an assessment of the quality of the grinding and homogeneity of the feed mixture. For the efficiency of grinding, serrated surfaces have been developed along four planes of the hammer, which maximizes the use of the working surfaces of the hammer and eliminates passive zones. The design parameters of the serrated surfaces are the step between the tops of adjacent serrations (t, mm), the height of the serrations (h, mm), the angle of inclination (α, °) and the sharpness of the serrations (o_z, °). It was found that it is necessary to strive to reduce the step between the tops of adjacent serrations t. The results of the experiments with four-sided serrated hammers showed that a significant portion of the crushed grain waste particles was smaller than 1 mm (25.36–34.34%); the particle size was over 1 mm and less than 2 mm (35.09–44.22%); the particle size was over 2 mm and less than 3.55 mm (27.59–28.73%), and an insignificant portion of particles was larger than 3.55 mm (0.99–2.98%). The experiments yielded the following results on the homogeneity of the mixing of grain waste and the control component: 86.6% (after 2 min), 87.2% (after 4 min) and 87.6% (after 6 min). The feed preparation device with the developed four-sided serrated hammers and impact-mixing mechanisms can produce sufficiently crushed and uniformly mixed feed mass. Full article

In cattle, the transfer of passive immunity from mother to calf across the placenta is limited. Therefore, providing quality colostrum or supplementing with additives that enhance this attribute is crucial to optimise the transfer of passive immunity (TPI). The objective of the present study was to investigate the effect of capsaicin on the absorption of immunoglobulins, metabolites, and enzymes to optimise TPI in neonatal calves, and to assess its impact on selected physiological parameters. Two experimental groups were established: a control group (CON; n = 8), which received colostrum in three feedings (at 1, 12, and 20 h after calving), and a capsaicin group (CAP; n = 8) which received 40 mg of capsaicin per kilogram of body weight added to the colostrum. Birth weight (CON = 36.7 ± 1.10 kg; CAP = 36.2 ± 2.64 kg) and weight at 48 h of age (CON = 38.5 ± 1.11 kg; CAP = 38.0 ± 2.82 kg) were similar between the two experimental groups. At 48 h post-colostrum feeding, the CAP group exhibited significantly higher serum concentrations of IgG, total protein, and albumin—up to 23.4 times greater than those observed in the CON group (p < 0.001). Moreover, levels of glucose, cholesterol, and triglycerides were significantly elevated in the CAP group compared to the CON group (p < 0.05). Similarly, higher concentrations of alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase were observed in the CAP group. These findings suggest that the inclusion of 40 mg of capsaicin per kilogram of body weight in colostrum is safe and contributes positively to improving TPI in crossbred Holstein calves raised at altitudes higher than 2500 m above sea level. Full article