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Various colors are implemented in solar cells without optical losses using light diffractions via grating structure. By utilizing the property of diffraction angle variations depending on the diffraction order, wavelength, grating period, and incident angle, many vivid colors are realized at different observation angles. Well-defined grating structures with periods of 770 nm and 1400 nm are uniformly fabricated on Cu(In,Ga)Se 2 thin-film solar cells by a nanotransfer lithography using ZnO nanoparticles. Color-to-angle sensitivity, color brightness, and diffraction efficiency depend on the grating period and incident angle. A wide range of colors, mainly resulting from the 1st-order diffraction are observed in the range of observation angles within 20°. The solar cell performances hardly degrade due to the negligible optical transmission loss in the nanograting structure. The grating applied solar cells show additional advantages: short-circuit current gains in oblique incident light and a self-cleaning effect due to the enhanced hydrophobicity. Through this study, the photovoltaic modules are expected to not only remain as electricity generators, but also become aesthetic structures that can provide aesthetic pleasure to people. ga1 • Colors were implemented in solar cells using a transparent nanograting structure. • A ZnO nanograting was simply imprinted on the Cu(In,Ga)Se 2 solar cells. • Many distinct colors were realized at various off-axis observation angles. • Solar cell performances hardly degraded due to negligible optical loss in the grating. • Nanograting enhanced hydrophobicity and optical gain under oblique incident light. [ABSTRACT FROM AUTHOR]

Abstract: Fabrication of imprint stamp is a key issue of nanoimprint lithography. In this study, we attempt to fabricate the nickel imprint stamp using hot embossing lithography and electroforming processes. As small as 50nm sized patterns of original silicon master were faithfully transferred to polyvinyl chloride (PVC) film. By electroforming on hot embossed PVC film, nickel stamp, which has the same patterns of original silicon master stamp, was successfully fabricated. [Copyright &y& Elsevier]

The colour printing technology based on interactions between geometric structures and light has various advantages over the pigment-based colour technology in terms of nontoxicity and ultrasmall pixel size. The asymmetric Fabry–Perot (F–P) cavity absorber is the simplest light-interacting structure, which can easily represent and control the colour by the thickness of the dielectric layer. However, for practical applications, an advanced manufacturing technique for the simultaneous generation of multiple reflective colours is required. In this study, we demonstrate F–P cavity absorbers with micropixels by overcoming the difficulties of multi-level pattern fabrication using a nanoimprinting approach. Our asymmetric F–P cavity absorber exhibited a high absorption (approximately 99%) in a wide visible light range upon the incorporation of lossy metallic materials, yielding vivid colours. A high-resolution image of eight different reflective colours was obtained by a one-step process. This demonstrates the potential of this technology for device applications such as high-resolution colour displays and colour patterns used for security functions. [ABSTRACT FROM AUTHOR]

Background: Poorly differentiated neuroendocrine carcinomas (NECs) originating from the gastrointestinal (GI) tract are rare and very highly malignant disease with a poor prognosis. Poorly differentiated NECs most commonly arise in the esophagus and the large bowel; however, they may occur within virtually any portion of the GI tract. It is known, however, that they do not typically occur in the small intestine.Case Report: A 21-year-old woman visited an emergency room with acute abdominal pain that commenced 2 days prior to her presentation. Thereafter, a computed tomography (CT) scan was notable for a small-intestine perforation, and huge masses were observed in the small intestine and the mesentery. The mass that was located at the ileum site is approximately 100 cm above the ileocecal (IC) valve, and while it is located on the anti-mesenteric border and it seems that luminal narrowing had occurred, an obstruction is absent. Also, a same-nature mass is on the mesentery. The pathologic reports confirmed a small-cell-type NEC with a mass size of 7.5 × 6.5 cm. The mitotic count is up to 24/10 high-power fields (HPFs), the results of the immunohistochemical stain are positive for CD56 and synaptophysin, and the Ki-67 level is 50%. %. After the operation, she was treated with Etoposide-Cisplatin (EP) chemotheraphy. Stable disease was seen during Etoposide-Cisplatin chemotheraphy. Liver metastasis was also confirmed after chemotheraphy. Additionally, Irinotecan and cisplatin were used for 3 cycles, but progression of disease, neutropenic fever, thrombocytopenia, general weakness persisted. Eventually, she died 1 year and 6 months after surgery.Conclusion: Ileum-located NECs are diagnosed very rarely. The most common locations for these tumors along the GI tract are the esophagus and the large intestine, but they can arise anywhere. The prognosis for NECs is poor due to the metastatic disease of most patients at the time of diagnosis. The role of adjuvant treatment requires further evaluation for the attainment of a better understanding of the overall treatment effect. [ABSTRACT FROM AUTHOR]

Abstract In this study, we developed a fabrication method of conductive and transparent Ag mesh electrodes on flexible polymer film at temperatures lower than 100 °C. Random patterned Ag mesh film was fabricated on a flexible PET substrate over 15 × 15 cm2 by a self-assembly process. It became conductive by a coupling process at low temperatures. The coupled Ag mesh film showed more than 88% transmittance in visible wavelength and less than 8.2 Ω sq−1 in sheet resistance with figure of merit (FoM) value of 350. This transparent flexible EMI shield film fabricated with a coupled Ag mesh pattern showed high EM shielding effectiveness of −23 dB at 1.5–10 GHz frequency with a high transparency of 88%. [ABSTRACT FROM AUTHOR]

Non-volatile memories (NVMs) using nanocrystals (NCs) as active materials can be applied to soft electronic devices requiring a low-temperature process because NCs do not require a heat treatment process for crystallization. In addition, memory devices can be implemented simply by using a patterning technique using a solution process. In this study, a flexible NiO ReRAM device was fabricated using a simple NC patterning method that controls the capillary force and dewetting of a NiO NC solution at low temperature. The switching behavior of a NiO NC based memory was clearly observed by conductive atomic force microscopy (c-AFM). [ABSTRACT FROM AUTHOR]

With the increasing use of building-integrated photovoltaic technology, it has become necessary for solar panels to blend in with their surroundings. Diffractive nanostructures can be used to reduce optical losses and create colorful solar cells. To make colors on Cu(In,Ga)Se 2 (CIGS) thin-film solar cells, we fabricated diffractive nanostructures by using nanoscale imprinting and transfer lithography methods. And we investigated how the material types and pattern shapes of the nanostructures influence the optical properties of solar cells, such as the short-circuit current density (J SC), coordination of color appearance, and color quality. We used two types of pillars and grating nanostructures of SiO 2 and TiO 2 layers on CIGS thin-film solar cells to produce various colors. The SiO 2 demonstrated an increase in J SC without significant loss of color quality compared to TiO 2. By utilizing a hexagonally arrayed pillar pattern, colors are observed at various angles on an axis different from the incident light, unlike colors observed only at a single angle in the grating structure. The nanoimprinting lithography process allowed us to produce high-quality nanostructures on both rigid glass and flexible stainless-steel substrates. [Display omitted] • Diffractive nanostructures abled color solar cells with minimizing efficiency loss. • Nanoscale imprinting and transfer lithography were used to make the nanostructures. • The coordinates and quality of the color were influenced by the materials and patterns of nanostructures. [ABSTRACT FROM AUTHOR]

Abstract: The InSe/GeSbTe stacked phase change materials were investigated at nano-scale for multi-level switching with a large sensing margin and fast switching. The 200nm nano-pillar devices of InSe material and InSe/GeSbTe materials were fabricated using NIL, and its electrical properties were characterized using conducting AFM system, that was connected to a pulse generator and a voltage source. In case of InSe based nano-pillar device, it was evaluated that the fast switching speed (<100ns) and large difference of resistance on–off ratio (>10,000) and exhibited only bi-level switching characteristics. In case of the InSe/GeSbTe PCMs structure exhibited three levels of resistance state with a few hundred times of difference between them with 100ns reset pulse. [Copyright &y& Elsevier]

Abstract: Phase change random access memory (PRAM) is one of the most promising non-volatile memories due to its ability to store digital data in the form of crystalline and amorphous phases of phase change materials. As a phase change material, Ge2Sb2Te5 (GST225) is usually used, due to its reversible phase transition capability with speeds of less than 100ns between the crystalline and amorphous phases. In order to fabricate highly integrated PRAM devices, sub micron- to nanometer-sized patterning of GST225 layer must be accomplished. In this study, 70nm-sized polymer patterns were fabricated using partial filling nanoimprint lithography (NIL) on a GST225 layer, which was deposited by RF sputtering. Then GST225 was etched using Ar/Cl2 plasma with an ICP etcher. Etch conditions, including Cl2 concentration, were optimized to obtain the vertical etch profile of the GST patterns. [Copyright &y& Elsevier]

Abstract: For future device applications, fabrication of the metal nano-patterns on various substrates, such as Si wafer, non-planar glass lens and flexible plastic films become important. Among various nano-patterning technologies, nano-transfer print method is one of the simplest techniques to fabricate metal nano-patterns. In nano-transfer printing process, thin Au layer is deposited on flexible PDMS mold, containing surface protrusion patterns, and the Au layer is transferred from PDMS mold to various substrates due to the difference of bonding strength of Au layer to PDMS mold and to the substrate. For effective transfer of Au layer, self-assembled monolayer, which has strong bonding to Au, is deposited on the substrate as a glue layer. In this study, complicated SAM layer coating process was replaced to simple UV/ozone treatment, which can activates the surface and form the –OH radicals. Using simple UV/ozone treatments on both Au and substrate, Au nano-pattern can be successfully transferred to as large as 6in. diameter Si wafer, without SAM coating process. High fidelity transfer of Au nano-patterns to non-planar glass lens and flexible PET film was also demonstrated. [Copyright &y& Elsevier]

Using the simple interference interactions in a three-layer thin film structure, absorbers in the near infrared with aesthetically pleasing reflective colouration were designed, fabricated, and characterised. By implementing the phase change material, vanadium dioxide (VO2), with its remarkable phase change properties, the absorbers are able to be switched between lower and higher absorption states depending on the external temperature. Conventional fabrication methods involving VO2 require an annealing process after deposition, but here, VO2 nanoparticles dispersed in a polymer mixture were employed to allow the simple and scalable spin coating process to be used, without the need for annealing. This simultaneously opens up the possibility of using flexible substrates for bendable devices. At a temperature of around 68 °C, a change in absorption of around 30% is observed between 800–1600 nm, while the vivid subtractive colours are maintained with almost no observable difference, on both silicon and flexible polymer-based substrates. The fabricated sample is robust to 2500 bending cycles, proving the possibility for scalable VO2 fabrication methods for practical applications. [ABSTRACT FROM AUTHOR]

Biomimetic inspiration from the moth-eye structure has led to many studies combining nanoimprint lithography (NIL) to realize low cost and large area anti-reflection (AR) coatings. However, the scope of application is severely limited by poor mechanical performance due to the intrinsic properties of the coating materials and the nanosized patterns. In this work, we demonstrate a moth-eye structured epoxy-siloxane molecular hybrid (ME-ESMH) fabricated using single UV-based NIL (UV-NIL) on a colorless polyimide (CPI), to be utilized as a flexible cover window (FCW) for foldable displays. Low reflection, a superhydrophobicity and good inward foldability were achieved, together with excellent thermal and chemical resistance. Furthermore, in situ uniaxial compression tests revealed that the fabricated structure can be elastically deformed and nearly restored to its original shape even after a large degree of compression. Our findings provide an easy-to-integrate solution for flexible hard coatings with superhydrophobic and AR properties, applicable to foldable optoelectronics. Image 1 • Hybrid material based moth-eye patterns are fabricated on CPI by UV-nanoimprinting. • Moth-eye patterned film shows excellent anti-reflection (AR) property with low haze. • The film exhibited mechanically resilient, flexible and self-cleaning characteristics. • The film is very promising for flexible hard AR coatings for foldable displays. [ABSTRACT FROM AUTHOR]

In this study, a nickel oxide (NiO) nanocrystal (NC) based flexible resistive memory device is demonstrated at temperature as low as 180 °C by ligand exchange process. The fabricated device for flexible application with structure Ni/NiO/Ni on PI substrate exhibits excellent switching characteristics with low set/reset voltages and stable resistance values in both ON and OFF states for over 100 switching cycles of memory operation. Also, this flexible memory device shows stable resistive switching properties under compressive stress with bending radius to 10 mm and consecutive bending cycles. The ReRAM fabricated by a low-temperature solution-process shows potential for next generation flexible electronics. • NiO Nanocrystal based flexible resistive memory device has been fabricated. • By introducing a ligand exchange method, the process temperature was lowered. • The flexible memory shows reliable resistive switching properties under compressive stress and consecutive bending cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • The active F–P MMA was composed of lossy Ag NPs and VO 2 NPs via a solution process. • The lossy Ag NP-assisted MMA exhibits high reflective spectral selectivity. • The active color shows good stability during the repeated VO 2 phase transition. • VO 2 -based MMA are very promising as an active color pixel for applications. Artificial structural color generation has attracted much attention in developing ink-free color technology for applications such as security devices, reflective displays, and functionalized color decoration. An asymmetric Fabry–Pérot (F–P) cavity-based absorber can play this role because of its advantages of an ultra-thin structure, lithographic-free manufacturing, and applicability to a large area. However, the optical response of F–P absorbers, which is determined by the structural parameters and compositions of the individual layers, is fixed at a single frequency, and only a static color can be passively implemented. In this study, we propose a new active metamaterial-based F–P absorber that exhibits dynamically tunable optical responses with temperature change. An active F–P absorber is fabricated by incorporating lossy nanoporous Ag nanoparticles (NPs) and a phase change material—vanadium dioxide (VO 2)— interlayer via a solution process. Coupled with finite-difference time-domain simulations and systematic experiments, we demonstrate that F–P absorbers generate enhanced reflective color purity due to their closely-coupled Ag NPs. The reflective colors were dynamically modulated by temperature changes owing to the variation of optical constants between the phase transition of the monoclinic VO 2. Furthermore, the demostrated tunable color image with micro-patterned absorbers opens the way for designing thermo-optical devices operating in the visible wavelength. [ABSTRACT FROM AUTHOR]

Flexible capacitive humidity sensors are promising for low-cost, wearable, and radio frequency identification sensors, but their nonlinear response is an important issue for practical applications. Herein, the linearity of humidity response was controlled by surface water wettability and operating frequency of sensor, and the mechanism was explained in detail by surface water condensation. For a sensor with a Ag interdigitated electrode (IDE) on a poly(ethylene terephthalate) substrate, the capacitance showed a small linear increase with humidity up to 70% RH but a large nonlinear increase in the higher range. The response linearity was increased by a hydrophobic surface treatment of self-assembled monolayer coating while it was decreased by an ultraviolet/ozone irradiation for hydrophilicity. It was also increased by increasing the frequency in the range of 1–100 kHz, more prominently on a more hydrophilic surface. Based on experiment and simulation, the increase in sensor capacitance was greatly dependent on the geometric pattern (e.g., size, number, and contact angle) and electrical permittivity of surface water droplets. A larger and more nonlinear humidity response resulted from a larger increase in the number of droplets with a smaller contact angle on a sensor surface with higher water wettability and also from a higher permittivity of water at a lower frequency. [ABSTRACT FROM AUTHOR]

We investigated whether textural parameters of peritumoral breast adipose tissue (AT) based on F-18 fluorodeoxyglucose (FDG) PET/CT could predict axillary lymph node metastasis in patients with breast cancer. A total of 326 breast cancer patients with preoperative FDG PET/CT were retrospectively enrolled. PET/CT images were visually assessed and the maximum FDG uptake of axillary lymph nodes (LN SUVmax) was measured. From peritumoral breast AT, 38 textural features of PET imaging were extracted. The diagnostic ability of PET based on visual analysis, LN SUVmax, and textural features of peritumoral breast AT for predicting axillary lymph node metastasis were assessed using the area under the receiver operating characteristic curve (AUC) values. Among the 38 peritumoral breast AT textural features, grey-level co-occurrence matrix (GLCM) entropy showed the highest AUC value (0.830) for predicting axillary lymph node metastasis. The value of GLCM entropy was higher than that of visual analysis (0.739; p < 0.05) and the AUC value was comparable to that of LN SUVmax (0.793; p > 0.05). In the subgroup analysis of patients with negative findings on visual analysis, GLCM entropy still showed a high diagnostic ability (AUC: 0.759) in predicting lymph node metastasis. The findings suggest a potential diagnostic role of PET/CT imaging features of peritumoral breast AT in predicting axillary lymph node metastasis in patients with breast cancer. [ABSTRACT FROM AUTHOR]

Abstract: It is known that a magnetic field changes the RI and the SPR angle of specific analytes. We have applied an external magnetic field to a surface plasmon resonance (SPR) sensor to exploit this phenomenon. A gold film is used for excitation of SPR in the sensor with a Kretschmann configuration. According to the concentration of 4-type analyte, we observed unique changes of the SPR angle due to the magnetic field, providing better classification of material type than a conventional SPR sensor. [Copyright &y& Elsevier]

Silver (Ag) metal-based structures are promising building blocks for next-generation photonics and electronics owing to their unique characteristics, such as high reflectivity, surface plasmonic resonance effects, high electrical conductivity, and tunable electron transport mechanisms. However, Ag structures exhibit poor sustainability in terms of device performance because harsh chemicals, particularly S 2- ions present in the air, can damage their structures, lowering their optical and electrical properties. Here, the surface chemistry of Ag structures with (3-mercaptopropyl)trimethoxysilane (MPTS) ligands at room temperature and under ambient conditions is engineered to prevent deterioration of their optical and electrical properties owing to S 2- exposure. Regardless of the dimensions of the Ag structures, the MPTS ligands can be applied to each dimension (0D, 1D, and 3D). Consequently, highly sustainable plasmonic effects (Δλ < 2 nm), Fabry-Perot cavity resonance structures (Δλ < 2 nm), reflectors (ΔR Reflectance < 0.5%), flexible electrodes (ΔR electrical < 0.1 Ω), and strain gauge sensors (ΔGF < 1), even in S 2- exposing conditions is achieved. This strategy is believed to significantly contribute to environmental pollution reduction by decreasing the volume of electronic waste., (© 2024 Wiley‐VCH GmbH.)

Silicon photonic waveguide resonators, such as microring resonators, photonic crystal waveguide cavities, and Fabry-Perot resonators based on the distributed Bragg reflectors, are key device components for silicon-based photonic integrated circuits (Si-PIC). For the Si-PIC with high integration density, the device footprints of the conventional photonic waveguide resonators need to be more compact. Inverse design, which is operated by the design expectation and different from the conventional design methods, has been investigated for reducing the photonic device components nowadays. In this paper, we inversely designed the silicon photonic waveguide reflectors for two target wavelengths: one is 1310 nm and the other is 1550 nm. The silicon photonic waveguide reflectors have reflectance of 0.99993 and 0.9955 for the wavelength of 1310 nm and 1550 nm each with 5-μm-long reflectors. Also, we theoretically investigated Fabry-Perot resonators based on the inversely designed photonic waveguide reflectors. Q factors of the Fabry-Perot resonators have been calculated to be 1.3 × 10 5 for the wavelength of 1310 nm and 2583 for the wavelength of 1550 nm. We have expected that the inversely designed photonic waveguide reflectors and their applications for the Fabry-Perot resonators can be utilized for compact passive/active device components such as wavelength filters, modulators, and external cavity lasers., Competing Interests: Conflict of interest: Authors state no conflicts of interest., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)

Purpose: Phyllodes tumors are similar to fibroadenomas in imaging and in pathological characteristics and are difficult to identify preoperatively. The purpose of this study was to analyze the recurrence rate after excision stratified by the surgical margin width and to propose and emphasize the "wait and watch" treatment strategy for benign phyllodes tumors., Methods: We performed a retrospective cohort study of patients diagnosed with benign phyllodes tumors by surgical excision between January 2000 and December 2022 at our institution. The medical and histopathological records were reviewed., Results: The results were obtained using the Cox proportional hazard regression and logistic regression. Resection margin status and recurrence were the independent variables. In each variable selection model, the resection margin was positive or less than 1 cm, and the recurrence rate was 3.7 and 1.04 times higher than the control group, but the difference was not statistically significant in 2 analyses., Conclusion: The surgical resection margin status of benign phyllodes tumors did not significantly affect locoregional recurrence. Therefore, follow-up imaging at short intervals without additional surgery is a feasible clinical option when the surgical resection margin is positive or less than 1 cm., Competing Interests: Conflict of Interest: No potential conflict of interest relevant to this article was reported., (Copyright © 2023, the Korean Surgical Society.)

The CRISPR-Cas system has emerged as the most efficient genome editing technique for a wide range of cells. Delivery of the Cas9-sgRNA ribonucleoprotein complex (Cas9 RNP) has gained popularity. The objective of this study was to develop a quantitative polymerase chain reaction (qPCR)-based assay to quantify the double-strand break reaction mediated by Cas9 RNP. To accomplish this, the dextransucrase gene ( dsr ) from Leuconostoc citreum was selected as the target DNA. The Cas9 protein was produced using recombinant Escherichia coli BL21, and two sgRNAs were synthesized through in vitro transcription to facilitate binding with the dsr gene. Under optimized in vitro conditions, the 2.6 kb dsr DNA was specifically cleaved into 1.1 and 1.5 kb fragments by both Cas9-sgRNA365 and Cas9-sgRNA433. By monitoring changes in dsr concentration using qPCR, the endonuclease activities of the two Cas9 RNPs were measured, and their efficiencies were compared. Specifically, the specific activities of dsr 365RNP and dsr 433RNP were 28.74 and 34.48 (unit/μg RNP), respectively. The versatility of this method was also verified using different target genes, uracil phosphoribosyl transferase ( upp ) gene, of Bifidobacterium bifidum and specific sgRNAs. The assay method was also utilized to determine the impact of high electrical field on Cas9 RNP activity during an efficient electroporation process. Overall, the results demonstrated that the qPCR-based method is an effective tool for measuring the endonuclease activity of Cas9 RNP.

The increasing advances in thermal radiation regulators have attracted growing interest, particularly in infrared sources, thermal management, and camouflage. Despite many advances in dynamic thermal emitters with great controllability, sustained external energy is required to maintain the desired emission. In this study, we present a polarization-driven thermal emission regulator based on a two-way control: i) phase change and ii) polarization tuning. Based on a conventional, non-volatile phase change material, i . e ., Ge 2 Sb 2 Te 5 (GST), we newly introduce an anisotropic medium for facile emissivity regulation without heat energy consumption. A rigorous coupled-wave analysis method provides design guidelines for finding optimal structural parameters. We utilized a simple glancing angle deposition process which induces tilted self-aligned nanocolumns with anisotropic properties. The fabricated sample shows polarization-sensitive thermal regulation through thermal imaging spectroscopic measurement. Additionally, we manufactured a multispectral visibly/thermally camouflaged patch that identifies encrypted information at a specific polarization state for a proof-of-concept demonstration., Competing Interests: The author declares no competing interests. The author does not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (© 2022 The Author(s).)

Appendiceal mucocele is a rare mucin-producing neoplasm of appendiceal origin. Due to its location and imaging findings, appendiceal mucocele is easily confused with tumors of the right adnexa. We present a rare case of a patient initially misdiagnosed with an ovarian tumor intraoperatively diagnosed as an appendiceal mucocele and successfully treated. A 66-year-old postmenopausal woman was admitted to the gynecology department for an asymptomatic pelvic mass. Preoperative pelvic imaging showed an 8-cm cystic mass. Exploratory laparoscopy for the suspected epithelial borderline tumor from the right ovary revealed a cystic mass in the right pelvic area and normal uterus, fallopian tubes, and ovaries. Intraoperative consultation with the general surgery department confirmed the appendiceal origin. Laparoscopic appendectomy was performed. Histopathological examination confirmed a low-grade mucinous neoplasm of appendiceal origin. The patient was discharged on a postoperative day 5 without complications. The outpatient follow-up performed 1 month later showed no evidence of disease progression. Despite the use of advanced diagnostic tools, appendiceal mucocele may be confused for ovarian malignancies. Because the clinical features of appendiceal mucocele are nonspecific, clinicians and radiologists know the specific imaging findings. A multidisciplinary approach including general surgery, gynecology, and radiology is required for preoperative diagnosis and treatment., Competing Interests: Jong Hyuk Yun is an editorial board member of the journal but was not involved in the peer reviewer selection, evaluation, or decision process of this article. No other potential conflicts of interest relevant to this article were reported., (Copyright © 2022 Korean Society of Surgical Oncology.)

The development of real-time and sensitive humidity sensors is in great demand from smart home automation and modern public health. We hereby proposed an ultrafast and full-color colorimetric humidity sensor that consists of chitosan hydrogel sandwiched by a disordered metal nanoparticle layer and reflecting substrate. This hydrogel-based resonator changes its resonant frequency to external humidity conditions because the chitosan hydrogels are swollen under wet state and contracted under dry state. The response time of the sensor is ~10 4 faster than that of the conventional Fabry-Pérot design. The origins of fast gas permeation are membrane pores created by gaps between the metal nanoparticles. Such instantaneous and tunable response of a new hydrogel resonator is then exploited for colorimetric sensors, anti-counterfeiting applications, and high-resolution displays.

Background: The present study aimed to investigate whether dual-phase F-18 sodium-fluoride (NaF) positron emission tomography/computed tomography (PET/CT) could improve the diagnostic accuracy of detecting bone metastasis in cancer patients with a solitary bone lesion compared to conventional F-18 NaF PET/CT., Methods: We retrospectively enrolled 113 cancer patients who underwent dual-phase F-18 NaF PET/CT for the differential diagnosis of a solitary bone lesion seen on bone scintigraphy. According to the dual-phase PET/CT protocol, an early-phase scan was acquired immediately after radiotracer injection and a conventional F-18 NaF PET/CT scan was performed. The diagnostic abilities of the visual analysis of conventional and dual-phase PET/CT scans and two quantitative parameters (lesion-to-blood pool uptake ratio on early-phase scan and lesion-to-bone uptake ratio on conventional scan) for detecting bone metastasis were compared. The final diagnosis of bone metastasis was made by histopathological confirmation or follow-up imaging studies., Results: A metastatic bone lesion was diagnosed in 28 patients (24.8%). The sensitivity, specificity, and accuracy were 100.0%, 70.6%, and 77.9%, respectively, for visual analysis of conventional F-18 NaF PET/CT, 92.9%, 42.4%, 54.9%, respectively, for lesion-to-bone uptake ratio, 96.4%, 88.2%, and 90.3%, respectively, for visual analysis of dual-phase PET/CT, and 92.9%, 81.2%, and 83.2%, respectively, for lesion-to-blood pool uptake ratio. Visual analysis of dual-phase PET/CT was shown to have the highest area under the receiver operating characteristic curve value (0.923; 95% CI, 0.858-0.965) among all parameters., Conclusions: Dual-phase F-18 NaF PET/CT showed a high diagnostic ability for detecting bone metastasis with improved specificity and accuracy compared to conventional F-18 NaF PET/CT in cancer patients. Dual-phase F-18 NaF PET/CT might help diagnose bone metastasis in patients with malignancies who were shown to have a solitary bone lesion on bone scintigraphy., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-607). The authors have no conflicts of interest to declare., (2020 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Purpose: High incidence of osteoporosis has been reported in breast cancer patients due to early menopause triggered by adjuvant treatment and temporary ovarian function suppression. In this study, we sought to determine whether long-term breast cancer survivors had an elevated risk of low bone density compared to the general population., Methods: Long-term breast cancer survivors who had been treated for more than 5 years were selected for this study. Data were obtained from medical records and using a questionnaire from the Korea National Health and Nutrition Examination Survey (KNHANES). An age-matched non-cancer control group was selected from the KNHANES records. Incidence of fracture and bone mineral density (BMD) were compared between the two groups., Results: In total, 74 long-term breast cancer survivors and 296 non-cancer controls were evaluated. The incidence of fracture did not differ between the two groups (P=0.130). No differences were detected in lumbar BMD (P=0.051) following adjustment for body mass index, while hip BMD was significantly lower in breast cancer survivors (P=0.028). Chemotherapy and endocrine treatment were not related to low BMD in breast cancer survivors. In more than half of the survivors, the 10-year risk of osteoporotic fracture was less than 1%., Conclusion: Long-term breast cancer survivors had low bone density but a comparable risk of fracture compared to non-cancer age-matched controls. Further studies on the factors related to low bone density in long-term breast cancer survivors are required., Competing Interests: CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported., (Copyright © Korean Society of Surgical Oncology.)

Recently, coloring based on nanostructure-light interaction has attracted much attention, because it has many advantages over pigment-based conventional coloring in terms of being non-toxic and highly durable in the environment, and providing high resolution. The asymmetric Fabry-Perot (FP) cavity absorber is the most manufacturable structure among coloring structures because it is simply produced and easily tunable. However, it cannot be applied practically because of the lack of a manufacturing technique that enables simultaneous fabrication of multi-color structures with different heights. Here, the fabrication of colored reflective characters based on various asymmetric FP absorbers with micrometer-scale pixel size are reported. Various cavities with different thicknesses are fabricated in a single step using UV imprint lithography and a simple deposition process. UV/visible spectroscopy is used to characterize the fabricated FP resonator. This absorber demonstrates high absorption, close to 90%, resulting in vivid colors with high resolution of 12700 DPI. It can be potentially used in reflective color displays field, functionalized color decorations, and security color patterns area. It is believed that this study would open up new possibilities for high density color printing in practical industry by introducing cost effective nanoimprint lithography technology.

Structural reflective colors based on Fabry-Perot (F-P) cavity resonances have attracted tremendous interest for diverse applications, such as color decoration and printing, display, and imaging devices. However, the asymmetric F-P cavity-based reflective colors proposed to date have low color purity and have difficulty to realize a desired vivid color because of a narrow absorption band characteristic in the visible light region. Here, a solution-processed, F-P ultra-broadband light absorber is newly proposed using a high lossy nanoporous material for vivid color generation. An asymmetric metal-insulator-metal structure consists of a high lossy nanoporous metallic film with coupled silver nanocrystals (Ag NCs) as the top layer. The absorbers not only increase the maximum absorption intensity up to ∼98% but also widen the bandwidth by 300 nm, resulting in high color purity in micrometer-scale pixels. Furthermore, the solution-based absorber shows potential to realize a high-resolution display pixel and anticounterfeiting devices having mechanical flexibility using the inkjet printing technology.

In this work, we introduce a low cost, room-temperature and atmospheric pressure based chemical method to produce highly transparent, conductive, and flexible nano-mesh structured electrodes using Ag nanocrystals (NCs). Sequential treatments of ligand exchange and reduction processes were developed to engineer the optoelectronic properties of Ag NC thin films. Combinatorial analysis indicates that the origin of the relatively low conductivity comes from the non-metallic compounds that are introduced during ligand exchange. The reduction process successfully removed these non-metallic compounds, yielding structurally uniform, optically more transparent, dispersive, and electrically more conductive thin films. We optimized the design of Ag NC thin film mesh structures, and achieved low sheet resistance (9.12 Ω □-1), high optical transmittance (94.7%), and the highest figure of merit (FOM) of 6.37 × 10-2. Solution processed flexible transparent heaters, touch pads, and wearable sensors are demonstrated, emphasizing the potential applications of Ag NC transparent electrodes in multifunctional sensors and devices.

We developed a simple and systematic method to fabricate optically tunable and thermally and chemically stable Au-Ag nanocrystal-based plasmonic metamaterials. An Ag nanocrystal-based metamaterial with desirable optical properties was fabricated via nanoimprinting and ligand-exchange process. Its optical properties were controlled by selectively substituting Ag atoms with Au atoms through a spontaneous galvanic replacement reaction. The developed Au-Ag-based metamaterials provide excellent tunable plasmonic properties required for various applications in the visible and near-infrared regions by controlling the Au-Ag composition according to the conditions of the galvanic displacement. Furthermore, their thermal and chemical stabilities significantly improved because of the protective Au thin layer on the surface. Using this developed process, chemically and thermally stable and flexible plasmonic metamaterials were successfully fabricated on a flexible polyester terephthalate substrate.

We demonstrate the fabrication of hierarchical materials by controlling the structure of highly ordered binary nanocrystal superlattices (BNSLs) on multiple length scales. Combinations of magnetic, plasmonic, semiconducting, and insulating colloidal nanocrystal (NC) building blocks are self-assembled into BNSL membranes via the liquid-interfacial assembly technique. Free-standing BNSL membranes are transferred onto topographically structured poly(dimethylsiloxane) molds via the Langmuir-Schaefer technique and then deposited in patterns onto substrates via transfer printing. BNSLs with different structural motifs are successfully patterned into various meso- and microstructures such as lines, circles, and even three-dimensional grids across large-area substrates. A combination of electron microscopy and grazing incidence small-angle X-ray scattering (GISAXS) measurements confirm the ordering of NC building blocks in meso- and micropatterned BNSLs. This technique demonstrates structural diversity in the design of hierarchical materials by assembling BNSLs from NC building blocks of different composition and size by patterning BNSLs into various size and shape superstructures of interest for a broad range of applications.

Ag and In co-doped SbTe phase change material (AgInSbTe) was used to fabricate nanopillar phase change memory. The AgInSbTe nanopillar type phase change device with 200 nm of diameter was fabricated by nanoimprint lithography and was reversibly changed between the resistances of 10(4) and 10(6) Omega by applying set/reset pulses using conducting atomic force microscopy. Due to the fast crystallization nature of AgInSbTe, the set operation of the device could be done with only 50 ns of set pulse. The fast crystallization nature of AgInSbTe is also responsible for the decrease in reset voltage of devices set with a short pulse.