Search Results (35)

A stable π-expanded o-quinodimethane derivative (2) was synthesized by photochemical dearomative cycloaddition of corannulene with an isolable dialkylsilylene (1) and isolated as a dark blue solid. Compound 2 adopts a very flat bowl shape in contrast to parent corannulene. Structural and spectroscopic characteristics, redox properties, and computational study suggest that 2 has a small but significant diradical character (y₀ = 0.11). One-electron reduction of 2 provides the corresponding radical anion as an isolable salt. Full article

The task of nucleus segmentation plays an important role in medical image analysis. However, due to the challenge of detecting small targets and complex boundaries in datasets, traditional methods often fail to achieve satisfactory results. Therefore, a novel nucleus segmentation method based on the U-Net architecture is proposed to overcome this issue. Firstly, we introduce a Weighted Feature Enhancement Unit (WFEU) in the encoder decoder fusion stage of U-Net. By assigning learnable weights to different feature maps, the network can adaptively enhance key features and suppress irrelevant or secondary features, thus maintaining high-precision segmentation performance in complex backgrounds. In addition, to further improve the performance of the network under different resolution features, we designed a Double-Stage Channel Optimization Module (DSCOM) in the first two layers of the model. This DSCOM effectively preserves high-resolution information and improves the segmentation accuracy of small targets and boundary regions through multi-level convolution operations and channel optimization. Finally, we proposed an Adaptive Fusion Loss Module (AFLM) that effectively balances different lossy targets by dynamically adjusting weights, thereby further improving the model’s performance in segmentation region consistency and boundary accuracy while maintaining classification accuracy. The experimental results on 2018 Data Science Bowl demonstrate that, compared to state-of-the-art segmentation models, our method shows significant advantages in multiple key metrics. Specifically, our model achieved an IOU score of 0.8660 and a Dice score of 0.9216, with a model parameter size of only 7.81 M. These results illustrate that the method proposed in this paper not only excels in the segmentation of complex shapes and small targets but also significantly enhances overall performance at lower computational costs. This research offers new insights and references for model design in future medical image segmentation tasks. Full article

Background: The effectiveness of paclitaxel (PTX) in treating non-small-cell lung carcinoma (NSCLC) is restricted by its poor pharmacokinetic profile and side effects. This limitation stems from the lack of a suitable delivery vector to efficiently target cancer cells. Therefore, there is a critical need to develop an efficient carrier for the optimised delivery of PTX in NSCLC therapy. Methods: The present study describes the fabrication of mesoporous polydopamine (mPDA) nano-bowls via an emulsion-induced interfacial anisotropic assembly method, designed for efficient entrapment of PTX and pH-responsive release behaviour. Results: The nano-bowls depicted a typical bowl-like shape, with connecting mesoporous channels and a central hollow cavity, allowing optimal loading of PTX. The fabricated nanocarrier system, mPDA-PTX-nb, had a mean hydrodynamic bowl diameter of 200.4 ± 5.2 nm and a surface charge of −39.2 ± 1.3 mV. The entrapment efficiency of PTX within the nano-bowls was found to be 95.7%, with a corresponding release of 85.1% achieved at the acidic pH 5.9 (simulated tumour microenvironment) at 48 h. Drug release was best fitted to the Peppas–Sahlin model, indicating the involvement of both diffusion and relaxation mechanisms. Treatment with mPDA-PTX-nb significantly suppressed A549 lung cancer cell proliferation at 48 and 72 h, resulting in cell viability of 14.0% and 9.3%, respectively, at the highest concentration (100 µg/mL). Conclusions: These results highlight the potential of mPDA-PTX-nb as an effective nanocarrier for PTX, promoting enhanced anti-proliferative effects in NSCLC therapy. Full article

This paper reviews the process of research, development and production of a training station for the optical recognition of dice parts with machine vision. This approach is chosen due to the lack of mechanical features to allow for classical orientation approaches. The embossed dots are about 0.1–0.2 mm deep so it is impossible to design classical traps. The orientation occurs purely by visual comparison to a reference image, part of the current camera job. The sequence of parts is controlled by the programmable logic controller(PLC)program, which manages the camera job-changing process via I/O signals, thus ensuring the right face of the die is captured by the camera and achieving the right predefined order of the sequence. When the preset number of dice in the sequence is reached, they are released back to the vibratory bowl feeder by a pneumatic separator. This way, all dice parts circulate until they are recognized by the camera. There are jobs for each possible orientation of the dice and also a small HMI where the dice sequences could be adjusted by the operator(generally students). The main benefit for the students is the opportunity to program the PLC and to adjust the camera jobs for the detection of each possible orientation. This relies upon the fact that during the fall from the return conveyor to the bowl feeder, the parts flip and, thus, change their previous orientation to another side. Experiments are conducted regarding the probability of obtaining orientation “5” and all the other possible states in order to statistically express the probability. Full article

This paper reviews the process of research, development and production of a system for the active orientation of small screws. The parts feature two different shapes on each side, which is suitable for machine vision inspection and not for classical vibratory bowl traps. When a part enters the jig, it is rotated at an angle of 90° for inspection. Based on the orientation, it may stay in this position or be rotated at 180°. This allows for active orientation; regardless of how the screw is presented to the camera, it is always positioned in the correct orientation by a servo mechanism. The main challenges are related to the small dimensions of the part. First of all, it has a diameter of only 3 mm and a length of 7 mm. A vibratory bowl feeder is used only for feeding and there is no orientation functionality in it. Afterwards, a vibratory linear feeder is placed so the ready parts are stacked and, thus, some buffer is created. This is important because vibratory bowl feeders are known for having unequal productivity in time and this could be solved by the linear feeder. Another key difficulty is the quality of the source parts. They are produced by several suppliers and sometimes there are chips and other remnants alongside the packages with screws. This imposes the need for a cleaning system as part of the servo actuator’s mechanism. Cleaning does not occur on every cycle; it is based on a timer that is predefined. Full article

The study investigates the surface morphology of polystyrene (PS) thin films, which were crafted by drying a cast emulsion layer on a microscope glass slide. A water-in-oil (w/o) emulsion was previously formulated by dispersing a small quantity of water (or an aqueous solution) into a chloroform–PS solution containing a dissolved emulsifier (surfactant). The resultant emulsion was spin-coated onto the glass slide. Subsequently, the type and dosage of surfactant utilized played a critical role in incubating the pattern formation during solvent evaporation. Mechanistically, the surface patterns resulted from a collaborative interplay of drying-induced droplet migration/partial coagulation and surface enrichment of surfactants. Span-80 induces a collection of bowl-shaped holes with a diameter of approximately 1 µm, while AOT induces an M-shaped geometrical pattern. The holes on PS film act as a microreactor to carry out the crystallization of acrylamide, as well as the growth of Ni-P alloy dendrites by electroless plating means. Alternatively, the dispersed aqueous droplet of the emulsion was utilized to conduct in situ reduction to grow copper nanoparticles. It is also noteworthy that the patterned PS films achieved exhibit diverse glass transition behaviors, attributed to the unique interaction of surfactant and PS chains. Full article

LiDAR-based digital terrain models (DTMs) represent an advance in the investigation of small-scale geomorphological features, including dolines of karst terrains. Important issues in doline morphometry are (i) which statistical distributions best model the size distribution of doline morphometric parameters and (ii) how to characterize the volume of dolines based on high-resolution DTMs. For backward compatibility, how previous datasets obtained predominantly from topographic maps relate to doline data derived from LiDAR is also examined. Our study area includes the karst plateaus of Aggtelek Karst and Slovak Karst national parks, whose caves are part of the UNESCO World Heritage. To characterize the study area, the relationships between doline parameters and topography were studied, as well as their geological characteristics. Our analysis revealed that the LiDAR-based doline density is 25% higher than the value calculated from topographic maps. Furthermore, LiDAR-based doline delineations are slightly larger and less rounded than in the case of topographic maps. The plateaus of the study area are characterized by low (5–10 km⁻²), moderate (10–30 km⁻²), and medium (30–35 km⁻²) doline densities. In terms of topography, the slope trend is decisive since the doline density is negligible in areas where the general slope is steeper than 12°. As for the lithology, 75% of the dolines can be linked to Wetterstein Limestone. The statistical distribution of the doline area can be well modeled by the lognormal distribution. To describe the DTM-based volume of dolines, a new parameter (k) is introduced to characterize their 3D shape: it is equal to the product of the area and the depth divided by the volume. This parameter indicates whether the idealized shape of the doline is closer to a cylinder, a bowl (calotte), a cone, or a funnel shape. The results show that most sinkholes in the study area have a transitional shape between a bowl (calotte) and a cone. Full article

A decline in pollinators is a real concern for the biodiversity and pollination of insect-dependent plants in landscapes and agriculture. Turfgrass is often presumed to be an ecological desert, as it is maintained at a low height with no floral resources for pollinators. Weeds are common on low-maintenance lawns in the southeastern USA and have rarely been studied as resources for pollinators. Thus, this study aimed to determine the abundance and diversity of bees on weed-infested lawns. Bees were sampled using yellow, white, and blue bowls and by bagging bees foraging on flowering weeds during the growing season from 2021 to 2023. Over three years, 539 bees from 16 genera were collected from weed-infested turfgrass lawns. Weeds were present throughout the growing seasons, and bees were also collected from them. Bombus, Apis, and Lasioglossum bees were the dominant genera collected. Large-sized bees, such as Bombus, were mostly collected from white clover (Trifolium repens L.), whereas small-sized bees, such as Lasioglossum, were mostly collected from common dandelion (Taraxacum officinale Weber). Other bee genera collected were Agapostemon, Augochlora, Augochlorella, Calliopsis, Ceratina, Epeolus, Halictus, Melissodes, Osmia, Panurginus, Ptilothrix, Svastra, and Xylocopa. This showed that a diverse group of bees utilized lawns infested with weeds. Full article

Synovial sarcomas are rare and highly aggressive soft-tissue sarcomas, primarily affecting adolescents and young adults aged 15–40 years. These tumors typically arise in the deep soft tissues, often near the large joints of the extremities. While the radiological features of these tumors are not definitely indicative, the presence of calcification in a soft-tissue mass (occurring in 30% of cases), adjacent to a joint, strongly suggests the diagnosis. Cross-sectional imaging characteristics play a crucial role in diagnosing synovial sarcomas. They often reveal significant characteristics such as multilobulation and pronounced heterogeneity (forming the “triple sign”), in addition to features like hemorrhage and fluid–fluid levels with septa (resulting in the “bowl of grapes” appearance). Nevertheless, the existence of non-aggressive features, such as gradual growth (with an average time to diagnosis of 2–4 years) and small size (initially measuring < 5 cm) with well-defined margins, can lead to an initial misclassification as a benign lesion. Larger size, older age, and higher tumor grade have been established as adverse predictive indicators for both local disease recurrence and the occurrence of metastasis. Recently, the prognostic importance of CT and MRI characteristics for synovial sarcomas was elucidated. These include factors like the absence of calcification, the presence of cystic components, hemorrhage, the bowl of grape sign, the triple sign, and intercompartmental extension. Wide surgical excision remains the established approach for definitive treatment. Gaining insight into and identifying the diverse range of presentations of synovial sarcomas, which correlate with the prognosis, might be helpful in achieving the optimal patient management. Full article

The Drake Passage is known for its abundant mesoscale eddies, but little is known about their three-dimensional characteristics, which hinders our understanding of their impact on eddy-induced transport and deep-sea circulation. A 10-year study was conducted using GLORYS12 Mercator Ocean reanalysis data from 2009 to 2018. The study analyzed the statistical characteristics of eddies in the Drake Passage, spanning from the surface down to a depth of 2000 m in three dimensions. The findings indicate that the mean radius of the eddies is 35.5 km, with a mean lifespan of 12.3 weeks and mean vorticity of 2.2 × 10⁻⁵ s⁻¹. The eddies are most active and energetic near the three main fronts and propagate north-eastward at an average distance of 97.8 km. The eddy parameters vary with water depth, with more anticyclones detected from the surface to 400 m, displaying a larger radius and longer propagation distance. Cyclones have longer lifespans and greater vorticity. However, beyond 400 m, there is not much difference between anticyclones and cyclones. Approximately 23.3% of the eddies reach a depth of 2000 m, with larger eddies tending to penetrate deeper. The eddies come in three different shapes, bowl-shaped (52.7%), lens-shaped (27.1%) and cone-shaped (20.2%). They exhibit annual and monthly distribution patterns. Due to its high latitude location, the Drake Passage has strong rotation and weak stratification, resulting in the generation of small and deep-reaching eddies. These eddies contribute to the formation of Antarctic intermediate water and lead to modulation of turbulent dissipation. Full article

The nutraceutical supplementation of Spirulina (Arthrospira platensis) in dogs and cats has not yet been investigated. The aim of this study was to evaluate if the dietary supplementation of increasing amounts of Spirulina for 6 weeks is palatable to pets and to assess the owner’s perception of such supplementation. The owners of the 60 dogs and 30 cats that participated in this study were instructed to daily provide Spirulina tablets starting with a daily amount of 0.4 g, 0.8 g, and 1.2 g for cats as well as small dogs, medium dogs, and large dogs, respectively, and allowing a dose escalation of 2× and 3× every 2 weeks. The daily amount (g/kg BW) of Spirulina ranged from 0.08 to 0.25 for cats, from 0.06 to 0.19 for small-sized dogs, from 0.05 to 0.15 for medium-sized dogs, and from 0.04 to 0.12 for large-sized dogs. Each owner completed a questionnaire at the time of recruitment and the end of each 2-week period. No significant effect on the fecal score, defecation frequency, vomiting, scratching, lacrimation, general health status, and behavioral attitudes was detected by the owners’ reported evaluations. Most animals accepted Spirulina tablets either administrated alone or mixed with food in the bowl. Daily supplementation of Spirulina for 6 weeks in the amounts provided in this study is therefore palatable and well tolerated by dogs and cats. Full article

A new type of 3D electrode detector, named here as the Implanted-Epi Silicon 3D-Spherical Electrode Detector, is proposed in this work. Epitaxial and ion implantation processes can be used in this new detector, allowing bowl-shaped electrodes to penetrate the silicon completely. The distance between the bowl cathode and the central collection electrode is basically the same, thus the total depletion voltage of Implanted-Epi Silicon 3D-Spherical Electrode Detectors is no longer directively correlated with the thickness of the silicon wafer, but only related to the electrode spacing. In this work, we model the device physics of this new structure and use a simulation program to conduct a systematic 3D simulation of its electrical characteristics, including electric potential and electric field distributions, electron concentration profile, leakage current, and capacitance, and compare it to the traditional 3D detectors. The theoretical and simulation study found that the internal electric potential of the new detector was smooth and no potential saddle point was found. The electric field is also uniform, and there is no zero field and a low electric field area. Compared with the traditional silicon 3D electrode detectors, the full depletion voltage is greatly reduced and the charge collection efficiency is improved. As a large electrode spacing (up to 500 μm) can be realized in the Implanted-Epi Silicon 3D-Spherical Electrode Detector thanks to their advantage of a greatly reduced full depletion voltage, detectors with large pixel cells (and thus small dead volume) can be developed for applications in photon science (X-ray, among others). Full article

The combined use of non-invasive on-site portable techniques, Raman microscopy, and X-ray fluorescence spectroscopy on seven imperial bowls and two decorated dishes, attributed to the reigns of the Kangxi, Yongzheng, Qianlong, and Daoguang emperors (Qing Dynasty), allows the identification of the coloring agents/opacifiers and composition types of the glazes and painted enamels. Particular attention is paid to the analysis of the elements used in the (blue) marks and those found in the blue, yellow, red, and honey/gilded backgrounds on which, or in reserve, a floral motif is principally drawn. The honey-colored background is made with gold nanoparticles associated with a lead- and arsenic-based flux. One of the red backgrounds is also based on gold nanoparticles, the second containing copper nanoparticles, both in lead-based silicate enamels like the blue and yellow backgrounds. Tin and arsenic are observed, but cassiterite (SnO₂) is clearly observed in one of the painted decors (dish) and in A676 yellow, whereas lead (calcium/potassium) arsenate is identified in most of the enamels. Yellow color is achieved with Pb-Sn-Sb pyrochlore (Naples yellow) with various Sb contents, although green color is mainly based on lead-tin oxide mixed with blue enamel. The technical solutions appear very different from one object to another, which leads one to think that each bowl is really a unique object and not an item produced in small series. The visual examination of some marks shows that they were made in overglaze (A608, A616, A630, A672). It is obvious that different types of cobalt sources were used for the imprinting of the marks: cobalt rich in manganese for bowl A615 (Yongzheng reign), cobalt rich in arsenic for bowl A613 (but not the blue mark), cobalt with copper (A616), and cobalt rich in arsenic and copper (A672). Thus, we have a variety of cobalt sources/mixtures. The high purity of cobalt used for A677 bowl indicates a production after ~1830–1850. Full article

This paper describes the simulative approach to calibrate an already extremely highly turbocharged industrial diesel engine for higher low-speed torque. The engine, which is already operating at its cylinder-pressure maximum, is to achieve close to 30 bar effective mean pressure through suitable calibration between the compression ratio, piston-bowl shape and injection strategy. The basic idea of the study is to lower the compression ratio for even higher injection masses and boost pressures, with the resulting disadvantages in the area of emissions and fuel consumption being partially compensated for by optimizations in the areas of piston shape and injection strategy. The simulations primarily involve the use of the 3D CFD software Converge CFD for in-cylinder calibration and a fully predictive 1D full-engine model in GT Suite. The simulations are based on a two-stage turbocharged 1950 cc four-cylinder industrial diesel engine, which is used for validation of the initial simulation. With the maximum increase in fuel mass and boost pressure, the effective mean pressure could be increased up to 28 bar, while specific consumption increased only slightly. Depending on the geometry, NOx or CO and UHC emissions could be reduced. Full article

The interaction of polycyclic aromatic hydrocarbons (PAHs) with water is of paramount importance in atmospheric and astrophysical contexts. We report here a combined theoretical and experimental study of corannulene-water interactions in low temperature matrices and of the matrix’s influence on the photoreactivity of corannulene with water. The theoretical study was performed using a mixed density functional based tight binding/force field approach to describe the corannulene-water clusters trapped in an argon matrix, together with Born-Oppenheimer molecular dynamics to determine finite-temperature IR spectra. The results are discussed in the light of experimental matrix isolation FTIR spectroscopic data. We show that in the solid phase, $\pi$ isomers of (C${}_{20}$H${}_{10}$)(H${}_2$O)${}_n$, with n = 2 or 3, are energetically favored. These $\pi$ complexes are characterized by small shifts in corannulene vibrational modes and large shifts in water bands. These $\pi$ structures, particularly stable in the case of the water trimer where the water cluster is trapped “inside” the corannulene bowl, may account for the difference in photoreactivity of non-planar–compared to planar–PAHs with water. Indeed, planar PAHs such as pyrene and coronene embedded in H${}_2$O:Ar matrices form $\sigma$ isomers and react with water to form alcohols and quinones under low energy UV irradiation, whereas no photoreactivity was observed for corannulene under the same experimental conditions. Full article