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기존 객체 검출에서 널리 사용되고 있는 YOLO 모델은 어떤 특징 벡터가 더 중요한지를 학습할 수 있는 어텐션 기능이 배제되어 있다. 따라서 본 논문에서는 기존 YOLO 모델의 객체 검출 성능을 향상할 수 있는 어텐션 YOLO 모델을 제안하고자 한다. 제안한 에텐션 모델은 입력 잎사귀 영상에서 배경 영역에는 질병에 관한 정보가 없고 오직 잎사귀 내부에만 질병을 구별할 수 있는 반점과 색상 정보가 존재한다는 것에서 착안했다. 입력 잎사귀 영상에서 배경, 잎사귀, 질병 영역을 구분할 수 있는 영상 분할 서브 네트워크를 YOLO의 특징 추출 서브 네트워크와 결합함으로써, 관심 영역에 대한 특징 구별력을 제고하고자 한다. 이를 통해, YOLO 모델에서 공간적으로 질병 관련 특징의 중요도를 강화할 수 있는 새로운 어텐션 모델을 소개하고자 한다. 그리고 실험 결과를 통해, 제안한 어텐션 YOLO 모델이 기존의 YOLO 모델 대비 평균 정밀도 평가에서 약 0.06 정도의 객체 검출 성능을 개선할 수 있음을 보이고자 한다.

Colloidal particles with a repulsive interparticle potential spontaneously form crystalline lattices, which are used as a motif for photonic materials. It is difficult to predict the crystal arrangement in spherical volume as lattices are incompatible with a spherical surface. Here, the optimum arrangement of charged colloids is experimentally investigated by encapsulating them in double-emulsion drops. Under conditions of strong interparticle repulsion, the colloidal crystal rapidly grows from the surface toward the center of the microcapsule, forming an onion-like arrangement. By contrast, for weak repulsion, crystallites slowly grow and fuse through rearrangement to form a single-crystal phase. Single-crystal structure is energetically favorable even for strong repulsion. Nevertheless, a high energy barrier to colloidal rearrangement kinetically arrests the onion-like structure formed by heterogeneous nucleation. Unlike the isotropic onion-shaped product, the anisotropic single-crystal-containing microcapsules selectively display-at certain orientations but not others-one of the distinct colors from the various crystal planes.

Colloidal crystallization is analogous to the crystallization in bulk atomic systems in various aspects, which has been explored as a model system. However, a real-time probing of the phenomenon still remains challenging. Here, a levitation system for a study of colloidal crystallization is demonstrated. Colloidal particles in a levitated droplet are gradually concentrated by isotropic evaporation of water from the surface of the droplet, resulting in crystallization. The structural change of the colloidal array during crystallization is investigated by simultaneously measuring the volume and reflectance spectra of the droplet. The crystal nucleates from the surface of the droplet at which the volume fraction exceeds the threshold and then the growth proceeds. The crystal growth behavior depends on the initial concentrations of colloidal particles and salts which determine the overall direction of crystal growth and interparticle spacing, respectively. The results show that a levitating bulk droplet has a great potential as a tool for in situ investigation of colloidal crystallization.

Technologies to monitor microenvironmental conditions and its spatial distribution are in high demand, yet remain unmet need. Herein, photonic microsensors are designed in a capsule format that can be injected, suspended, and implanted in any target volume. Colorimetric sensors are loaded in the core of microcapsules by assembling core-shell colloids into crystallites through the depletion attraction. The shells of the colloids are made of a temperature-responsive hydrogel, which enables the crystallites to rapidly and widely tune the structural color in response to a change in temperature while maintaining close-packed arrays. The spherical symmetry of the microcapsules renders them optically isotropic, i.e., displaying orientation-independent color. In addition, as a solid membrane is used to protect the delicate crystallites from external stresses, their high stability is assured. More importantly, each microcapsule reports the temperature of its microenvironment so that a suspension of capsules can provide information on the spatial distribution of the temperature.

Crystalline or glassy materials made of colloidal nanoparticles show distinctive photonic effects; the crystals exhibit sparkling colors with strong iridescence, while the glasses show noniridescent colors. Both colors are the results of constructive interference of the reflected light by the nonadsorbing nanostructures. Such colored materials have potential applications as nonfading colorants in reflective color displays, optical sensors, coatings, and cosmetics. All of these applications require granular format of the nanostructures; however, precise control of the nanostructures from amorphous to crystalline over the submillimeter length scale remains challenging. Here, we present micrometer-level control of photonic nanostructures confined in microcapsules through osmotic-pressure-mediated concentration. We encapsulate aqueous suspensions of colloidal particles using double-emulsion drops with ultrathin layers of photocurable resin. The microcapsules are then isotropically compressed by imposing a pos...

Chameleons use a non-close-packed array of guanine nanocrystals in iridophores to develop and tune skin colors in the full visible range. Inspired by the biological process uncovered in panther chameleons, we designed photonic films containing a non-close-packed face-centered-cubic array of silica particles embedded in an elastomer. The non-close-packed array is formed by interparticle repulsion exerted by solvation layers on the particle surface, which is rapidly captured in the elastomer by photocuring of the dispersion medium. The artificial skin exhibits a structural color that shifts from red to blue under stretching or compression. The separation between inelastic particles enables tuning without experiencing significant rearrangement of particles, providing elastic deformation and reversible color change, as chameleons do. The simple fabrication procedure consists of film casting and UV irradiation, potentially enabling the continuous high-throughput production. The mechanochromic property of the photonic films enables the visualization of deformation or stress with colors, which is potentially beneficial for various applications, including mechanical sensors, sound-vision transformers, and color display.

Structurally colored materials could potentially replace dyes and pigments in many applications, but it is challenging to fabricate structural colors that mimic the appearance of absorbing pigments. We demonstrate the microfluidic fabrication of "photonic pigments" consisting of microcapsules containing dense amorphous packings of core-shell colloidal particles. These microcapsules show non-iridescent structural colors that are independent of viewing angle, a critical requirement for applications such as displays or coatings. We show that the design of the microcapsules facilitates the suppression of incoherent and multiple scattering, enabling the fabrication of photonic pigments with colors spanning the visible spectrum. Our findings should provide new insights into the design and synthesis of materials with structural colors.

Lowering tree height has been a key practice for efficient management of persimmon orchards. This experiment was conducted to assess whether fertilization rates could be reduced after lowering the tree height by heavy pruning. Twelve-year-old 'Uenishiwase' persimmon trees were lowered to 2 m from over 3 m by severe dormant pruning, and then conventional fertilization rate was applied to some trees in April (N 224 g, 172 g, and 172 g per tree), June (N 112 g and 99 g per tree), and October (N 112 g and 99 g per tree). At the same time, 1/3 or 2/3 of the conventional rate and none were applied to other trees, respectively. Non-application decreased shoot length and reduced number of unnecessary secondary shoots by 39% compared with the conventional rate, not affecting yield and weight, color, firmness, and soluble solids of fruits. No significant difference was also found in the yield and the fruit characteristics among the trees fertilized with different rates. Concentrations of soluble sugars, starch, N, and K of dormant shoots in March of the following year were not significantly changed by the different treatments of the previous year. There was no significant difference of shoot growth and yield among the treatments the following year when the same fertilization rate was supplied to all the trees. Results indicated that fertilization rate could be reduced to less than 1/3 of conventional rate to save the cost and stabilize shoot vigor when tree height is lowered by severe pruning.

Recent advances in microfluidics have enabled the controlled production of multiple-emulsion drops with onion-like topology. The multiple-emulsion drops possess an intrinsic core-shell geometry, which makes them useful as templates to create microcapsules with a solid membrane. High flexibility in the selection of materials and hierarchical order, achieved by microfluidic technologies, has provided versatility in the membrane properties and microcapsule functions. The microcapsules are now designed not just for storage and release of encapsulants but for sensing microenvironments, developing structural colours, and many other uses. This article reviews the current state of the art in the microfluidic-based production of multiple-emulsion drops and functional microcapsules. The three main sections of this paper discuss distinct microfluidic techniques developed for the generation of multiple emulsions, four representative methods used for solid membrane formation, and various applications of functional microcapsules. Finally, we outline the current limitations and future perspectives of microfluidics and microcapsules.

Colloidal crystals are promising structures for photonic applications requiring dynamic control over optical properties. However, for ease of processing and reconfigurability, the crystals should be encapsulated to form 'ink' capsules rather than confined in a thin film. Here we demonstrate a class of encapsulated colloidal photonic structures whose optical properties can be controlled through osmotic pressure. The ordering and separation of the particles within the microfluidically created capsules can be tuned by changing the colloidal concentration through osmotic pressure-induced control of the size of the individual capsules, modulating photonic stop band. The rubber capsules exhibit a reversible change in the diffracted colour, depending on osmotic pressure, a property we call osmochromaticity. The high encapsulation efficiency and capsule uniformity of this microfluidic approach, combined with the highly reconfigurable shapes and the broad control over photonic properties, make this class of structures particularly suitable for photonic applications such as electronic inks and reflective displays.

Isotropic microparticles prepared from a suspension that undergoes polymerization have long been used for a variety of applications. Bulk emulsification procedures produce polydisperse emulsion droplets that are transformed into spherical microparticles through chemical or physical consolidation. Recent advances in droplet microfluidics have enabled the production of monodisperse emulsions that yield highly uniform microparticles, albeit only on a drop-by-drop basis. In addition, microfluidic devices have provided a variety of means for particle functionalization through shaping, compartmentalizing, and microstructuring. These functionalized particles have significant potential for practical applications as a new class of colloidal materials. This feature article describes the current state of the art in the microfluidic-based synthesis of monodisperse functional microparticles. The three main sections of this feature article discuss the formation of isotropic microparticles, engineered microparticles, and hybrid microparticles. The complexities of the shape, compartment, and microstructure of these microparticles increase systematically from the isotropic to the hybrid types. Each section discusses the key idea underlying the design of the particles, their functionalities, and their applications. Finally, we outline the current limitations and future perspectives on microfluidic techniques used to produce microparticles.

A 63-year-old man complained of intermittent motor weakness of his arm. The magnetic resonance image (MRI) of his brain displayed a high signal lesion in right cingulate gyrus on T2 weighted image. One year later, he showed a stuporous mental status with repeated seizures, and the follow-up brain MRI showed heterogeneously enhanced mass associated with bleeding. He was treated with surgery and radiotherapy for secondary glioblastomas in right cingulate gyrus. One year more later, a mass recurred on the left frontal base, and gliosarcoma was diagnosed. After tumor resection, ventriculoperitoneal shunt, chemotherapy, and re-radiation therapy, all brain lesions were stable. Fourteen months after the diagnosis of gliosarcoma, he complained of dyspnea and back pain. Torso positron emission tomography/computed tomography revealed multiple metastatic lesions in both lungs, pericardium, pleura, liver, lymph nodes, and bones, and metastatic gliosarcoma was diagnosed. One month later, the patient died because of the systemic metastases. We present an unusual case of secondary gliosarcoma with stable brain lesions and extensive systemic metastases.

Objective To report an observational investigation of small high attenuated foci in computed tomography (CT) scan followed by brain parenchymal catheterization. Methods From January 2011 to March 2015, we retrospectively reviewed the 381 patients who had undergone brain catheterization in our clinic and enrolled the patients who had newly developed high attenuation foci in the postoperative CT scans. The brain CT scans were reviewed about the lesion location, Hounsfield Unit (HU) and the time of appearance. Results Twenty seven of 381 patients had high attenuation foci in CT scans after the procedure. The location of high density lesions was as follows: parenchyma in 9 (33.3%) cases, ventricle in 5 (18.5%), combined in parenchyma and ventricle in 13 (48.1%). The lesions were identified in the catheter tract in parenchymal type, and catheter-lodged frontal horn or choroid plexus in ventricular type. We could not find the calcific foci before the catheter removal, and those were found after removal in all cases. The time of appearance after the removal was variable from 0 to 14 days (mean 4.2, median 3). The regular rules of HU change in CT scans were not found as times go on. Conclusion The high attenuation foci in CT scans were bone dust originated from skull during operation. Although these lesions did not make troubles, we should clean the operation field before the insertion of brain catheter and we may use another material, like Surgicel to seal up the burr hole instead of bone dust in the end of operation.

Objective Cerebral endothelial cells have unique biological features and are fascinating candidate cells for stroke therapy. Methods In order to understand the molecular mechanisms of human cerebral endothelial cell (hCMEC/D3) transplantation in a rat stroke model, we performed proteomic analysis using 2-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Protein expression was confirmed by quantitative real-time PCR and Western blot. Results Several protein spots were identified by gel electrophoresis in the sham, cerebral ischemia (CI), and CI with hCMEC/D3 treatment cerebral ischemia with cell transplantation (CT) groups, and we identified 14 differentially expressed proteins in the CT group. Proteins involved in mitochondrial dysfunction (paraplegin matrix AAA peptidase subunit, SPG7), neuroinflammation (peroxiredoxin 6, PRDX6), and neuronal death (zinc finger protein 90, ZFP90) were markedly reduced in the CT group compared with the CI group. The expression of chloride intracellular channel 4 proteins involved in post-ischemic vasculogenesis was significantly decreased in the CI group but comparable to sham in the CT group. Conclusion These results contribute to our understanding of the early phase processes that follow cerebral endothelial cell treatment in CI. Moreover, some of the identified proteins may present promising new targets for stroke therapy.