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Abstract The examination of entanglement across various degrees of freedom has been pivotal in augmenting our understanding of fundamental physics, extending to high dimensional quantum states, and promising the scalability of quantum technologies. In this paper, we demonstrate the photon number path entanglement in the frequency domain by implementing a frequency beam splitter that converts the single-photon frequency to another with 50% probability using Bragg scattering four-wave mixing. The two-photon NOON state in a single-mode fiber is generated in the frequency domain, manifesting the two-photon interference with two-fold enhanced resolution compared to that of single-photon interference, showing the outstanding stability of the interferometer. This successful translation of quantum states in the frequency domain will pave the way toward the discovery of fascinating quantum phenomena and scalable quantum information processing.

Recently, interest in cancer immunotherapy has increased over traditional anti-cancer therapies such as chemotherapy or targeted therapy. Natural killer (NK) cells are part of the immune cell family and essential to tumor immunotherapy as they detect and kill cancer cells. However, the disadvantage of NK cells is that cell culture is difficult. In this study, porous microgels have been fabricated using microfluidic channels to effectively culture NK cells. Microgel fabrication using microfluidics can be mass-produced in a short time and can be made in a uniform size. Microgels consist of photo cross-linkable polymers such as methacrylic gelatin (GelMa) and can be regulated via controlled GelMa concentrations. NK92 cell-laden three-dimensional (3D) microgels increase mRNA expression levels, NK92 cell proliferation, cytokine release, and anti-tumor efficacy, compared with two-dimensional (2D) cultures. In addition, the study confirms that 3D-cultured NK92 cells enhance anti-tumor effects compared with enhancement by 2D-cultured NK92 cells in the K562 leukemia mouse model. Microgels containing healthy NK cells are designed to completely degrade after 5 days allowing NK cells to be released to achieve cell-to-cell interaction with cancer cells. Overall, this microgel system provides a new cell culture platform for the effective culturing of NK cells and a new strategy for developing immune cell therapy.

The lithium-ion battery (LIB) is a promising energy storage system that has dominated the energy market due to its low cost, high specific capacity, and energy density, while still meeting the energy consumption requirements of current appliances. The simple design of LIBs in various formats—such as coin cells, pouch cells, cylindrical cells, etc.—along with the latest scientific findings, trends, data collection, and effective research methods, has been summarized previously. These papers addressed individual design parameters as well as provided a general overview of LIBs. They also included characterization techniques, selection of new electrodes and electrolytes, their properties, analysis of electrochemical reaction mechanisms, and reviews of recent research findings. Additionally, some articles on computer simulations and mathematical modeling have examined the design of full-cell LIBs for power grid and electric vehicle applications. To fully understand LIB operation, a simple and concise report on design parameters and modification strategies is essential. This literature aims to summarize the design parameters that are often overlooked in academic research for the development of full-cell LIBs.

Spontaneous parametric down-conversion (SPDC) has become a key method for generating entangled photon pairs. Periodically poled thin-film lithium niobate (TFLN) waveguides induce strong SPDC but require complex fabrication processes. In this work, we experimentally demonstrate efficient SPDC and second harmonic generation using modal phase matching methods. This is achieved with inverse-designed optical mode converters and low-loss optical waveguides in a single nanofabrication process. Inverse design methods provide enhanced functionalities and compact footprints for the converter. Despite the extensive achievements in inverse-designed photonic integrated circuits, the potential of inverse-designed TFLN quantum photonic devices has been seldom explored. The device shows an on-chip conversion efficiency of 3.95% W−1 cm−2 in second harmonic generation measurements and a coincidence count rate up to 21.2 kHz in SPDC experiments. This work highlights the potential of the inverse-designed TFLN photonic devices and paves the way for their applications in on-chip nonlinear or quantum optics.

Abstract The SARS‐CoV‐2 caused COVID‐19 pandemic has posed a global health hazard. While some vaccines have been developed, protection against viral infection is not perfect because of the urgent approval process and the emergence of mutant SARS‐CoV‐2 variants. Here, we employed UDCA as an FXR antagonist to regulate ACE2 expression, which is one of the key pathways activated by SARS‐CoV‐2 Delta variant infection. UDCA is a well‐known reagent of liver health supplements and the only clinically approved bile acid. In this paper, we investigated the protective efficacy of UDCA on Omicron variation, since it has previously been verified for protection against Delta variant. When co‐housing with an Omicron variant‐infected hamster group resulted in spontaneous airborne transmission, the UDCA pre‐supplied group was protected from weight loss relative to the non‐treated group at 4 days post‐infection by more than 5%–10%. Furthermore, UDCA‐treated groups had a 3‐fold decrease in ACE2 expression in nasal cavities, as well as reduced viral expressing genes in the respiratory tract. Here, the data show that the UDCA serves an alternative option for preventive drug, providing SARS‐CoV‐2 protection against not only Delta but also Omicron variant. Our results of this study will help to propose drug‐repositioning of UDCA from liver health supplement to preventive drug of SARS‐CoV‐2 infection.

Dynamic object detection is essential for ensuring safe and reliable autonomous driving. Recently, light detection and ranging (LiDAR)-based object detection has been introduced and shown excellent performance on various benchmarks. Although LiDAR sensors have excellent accuracy in estimating distance, they lack texture or color information and have a lower resolution than conventional cameras. In addition, performance degradation occurs when a LiDAR-based object detection model is applied to different driving environments or when sensors from different LiDAR manufacturers are utilized owing to the domain gap phenomenon. To address these issues, a sensor-fusion-based object detection and classification method is proposed. The proposed method operates in real time, making it suitable for integration into autonomous vehicles. It performs well on our custom dataset and on publicly available datasets, demonstrating its effectiveness in real-world road environments. In addition, we will make available a novel three-dimensional moving object detection dataset called ETRI 3D MOD.

Abstract Food waste is a growing global concern, necessitating effective treatment solutions. South Korea stands out with over 90% of its food waste being recycled, driven by robust resource circulation policies. Across Asia, anaerobic digestion processes are favored for food waste treatment due to their economic and environmental advantages. The South Korean Government aims to expand anaerobic digestion to ensure stable organic waste treatment. However, the 2019 outbreak of African swine fever (ASF) in pig farms led to the cessation of wet feed production, comprising 22% of total feed. This has increased the pressure on alternative recycling methods. The handling of food waste leachate, generating around 1080 t/d during treatment, has become a concern due to the discontinuation of wet feed production. The objective of this study is to develop a food waste policy. It begins by assessing food waste and leachate generation through field surveys of 346 treatment facilities engaged in pretreatment, feeding, composting, and biogasification. To mitigate the impact of ASF outbreaks in the short term, a proposed solution involves diverting food waste leachate to existing sewage treatment plant digesters during non-injection weekends and other off-peak times. This measure aims to completely treat the maximum discharge of approximately 2000 t/d during the peak summer ASF outbreak periods. For the long term, a strategy involving anaerobic digestion is suggested in response to the gradual reduction in wet or dry feed production, along with composting, the conventional treatment method. This transition not only curbs greenhouse gas emissions but also enhances biogas production, a renewable energy source. These efforts align with the Korean Green New Deal’s goal of achieving a 20% share of renewable energy by 2030.

Abstract Background Patients face a serious threat if a solid tumor leaves behind partial residuals or cannot be completely removed after surgical resection. Immunotherapy has attracted attention as a method to prevent this condition. However, the conventional immunotherapy method targeting solid tumors, that is, intravenous injection, has limitations in homing in on the tumor and in vivo expansion and has not shown effective clinical results. Method To overcome these limitations, NK cells (Natural killer cells) were encapsulated in micro/macropore-forming hydrogels using 3D bioprinting to target solid tumors. Sodium alginate and gelatin were used to prepare micro-macroporous hydrogels. The gelatin contained in the alginate hydrogel was removed because of the thermal sensitivity of the gelatin, which can generate interconnected micropores where the gelatin was released. Therefore, macropores can be formed through bioprinting and micropores can be formed using thermally sensitive gelatin to make macroporous hydrogels. Results It was confirmed that intentionally formed micropores could help NK cells to aggregate easily, which enhances cell viability, lysis activity, and cytokine release. Macropores can be formed using 3D bioprinting, which enables NK cells to receive the essential elements. We also characterized the functionality of NK 92 and zEGFR-CAR-NK cells in the pore-forming hydrogel. The antitumor effects on leukemia and solid tumors were investigated using an in vitro model. Conclusion We demonstrated that the hydrogel encapsulating NK cells created an appropriate micro–macro environment for clinical applications of NK cell therapy for both leukemia and solid tumors via 3D bioprinting. 3D bioprinting makes macro-scale clinical applications possible, and the automatic process shows potential for development as an off-the-shelf immunotherapy product. This immunotherapy system could provide a clinical option for preventing tumor relapse and metastasis after tumor resection. Graphical Abstract Micro/macropore-forming hydrogel with NK cells fabricated by 3D bioprinting and implanted into the tumor site.

Extrusion-based bioprinting technology is widely used for tissue regeneration and reconstruction. However, the method that uses only hydrogel as the bioink base material exhibits limited biofunctional properties and needs improvement to achieve the desired tissue regeneration. In this study, we present a three-dimensionally printed bioactive microparticle-loaded scaffold for use in bone regeneration applications. The unique structure of the microparticles provided sustained release of growth factor for > 4 weeks without the use of toxic or harmful substances. Before and after printing, the optimal particle ratio in the bioink for cell viability demonstrated a survival rate of ≥ 85% over 7 days. Notably, osteogenic differentiation and mineralization—mediated by human periosteum-derived cells in scaffolds with bioactive microparticles—increased over a 2-week interval. Here, we present an alternative bioprinting strategy that uses the sustained release of bioactive microparticles to improve biofunctional properties in a manner that is acceptable for clinical bone regeneration applications.

Graphislactone A (GPA), a secondary metabolite derived from a mycobiont found in the lichens of the genus Graphis, exhibits antioxidant properties. However, the potential biological functions and therapeutic applications of GPA at the cellular and animal levels have not yet been investigated. In the present study, we explored the therapeutic potential of GPA in mitigating non-alcoholic fatty liver disease (NAFLD) and its underlying mechanisms through a series of experiments using various cell lines and animal models. GPA demonstrated antioxidant capacity on a par with that of vitamin C in cultured hepatocytes and reduced the inflammatory response induced by lipopolysaccharide in primary macrophages. However, in animal studies using an NAFLD mouse model, GPA had a milder impact on liver inflammation while markedly attenuating hepatic steatosis. This effect was confirmed in an animal model of early fatty liver disease without inflammation. Mechanistically, GPA inhibited lipogenesis rather than fat oxidation in cultured hepatocytes. Similarly, RNA sequencing data revealed intriguing associations between GPA and the adipogenic pathways during adipocyte differentiation. GPA effectively reduced lipid accumulation and suppressed lipogenic gene expression in AML12 hepatocytes and 3T3-L1 adipocytes. In summary, our study demonstrates the potential application of GPA to protect against hepatic steatosis in vivo and suggests a novel role for GPA as an underlying mechanism in lipogenesis, paving the way for future exploration of its therapeutic potential.

The polyethylene lithium-ion battery separator is coated with a polymer by means of a roll-to-roll (R2R) gravure coating scheme to enhance the thermal stability. The polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) is gravure-coated, and the pores are fabricated based on online nonsolvent-induced phase separation (NIPS). N-methylpyrrolidone is used as a solvent, and deionized water or a methanol mixture thereof is exploited as a nonsolvent in NIPS. Scanning electron microscopy confirms that the polymer film is formed and that the pores are well developed. The thermal shrinkage decreased by 20.0% and 23.2% compared to that of the bare separator due to the coating of PVDF and PVDF-HFP, respectively. The R2R gravure coating scheme is proven to be fully functional to tailor the properties of lithium-ion battery separators.

There are fundamental difficulties in obtaining material type of an arbitrary object using traditional sensors. Existing material type recognition methods mostly focus on color based visual features and object-prior. Surface reflectance is another critical clue in the characterization of certain material type and can be observed by traditional sensors such as color camera and time-of-flight depth sensor. A material type is characterized well by relevant surface reflectance together with traditional visual appearance providing better description for material type recognition. In this work, we propose a material type recognition method based on both color and reflectance features using deep neural network. Proposed method is evaluated on both public and our own data sets showing promising material type recognition results.

Low bone mass can occur in children and adolescents with numerous chronic conditions; however, the influence of abnormal thyroid hormone and thyroid-stimulating hormone (TSH) levels on low bone mineral density (BMD) in children and adolescents remains controversial. Investigating the effects of excessive or deficient thyroid hormone and TSH levels on the risk of childhood bone fragility may provide a better understanding of the role of thyroid function on bone density in the pediatric population. The triiodothyronine (T3), thyroxine (T4), and TSH levels and BMD of 619 children diagnosed with various underlying conditions and whose treatment was completed were simultaneously assessed. The T3, free thyroxine (FT4), and TSH levels were subcategorized based on the age-matched reference range, and the lumbar spine BMD (LSBMD) data were compared. The mean LSBMD z-score was 0.49 ± 1.28, while T3, FT4, and TSH levels were 1.25 ± 0.29 ng/mL, 1.28 ± 0.19 ng/dL, and 2.76 ± 1.87 µU/mL, respectively. Both lumbar and femoral BMD z-scores were lower in children with abnormal TSH levels. TSH abnormality was the strongest risk factor for decreased LSBMD z-scores, and thus could be an early indicator of low BMD in children and adolescents with various underlying conditions.

Topological data analysis (TDA) characterizes the global structure of data based on topological invariants such as persistent homology, whereas convolutional neural networks (CNNs) are capable of characterizing local features in the global structure of the data. In contrast, a combined model of TDA and CNN, a family of multimodal networks, simultaneously takes the image and the corresponding topological features as the input to the network for classification, thereby significantly improving the performance of a single CNN. This innovative approach has been recently successful in various applications. However, there is a lack of explanation regarding how and why topological signatures, when combined with a CNN, improve discriminative power. In this paper, we use persistent homology to compute topological features and subsequently demonstrate both qualitatively and quantitatively the effects of topological signatures on a CNN model, for which the Grad-CAM analysis of multimodal networks and topological inverse image map are proposed and appropriately utilized. For experimental validation, we utilize two famous datasets: the transient versus bogus image dataset and the HAM10000 dataset. Using Grad-CAM analysis of multimodal networks, we demonstrate that topological features enforce the image network of a CNN to focus more on significant and meaningful regions across images rather than task-irrelevant artifacts such as background noise and texture.

Several electrode materials have been developed to provide high energy density and a long calendar life at a low cost for lithium-ion batteries (LIBs). Iron (III) vanadate (FeVO4), a semiconductor material that follows insertion/extraction chemistry with a redox reaction and provides high theoretical capacity, is an auspicious choice of anode material for LIBs. The correlation is investigated between calcination temperatures, morphology, particle size, physicochemical properties, and their effect on the electrochemical performance of FeVO4 under different binders. The crystallite size, particle size, and tap density increase while the specific surface area (SBET) decreases upon increasing the calcination temperature (500 °C, 600 °C, and 700 °C). The specific capacities are reduced by increasing the calcination temperature and particle size. Furthermore, FeVO4 fabricated with different binders (35 wt.% PAA and 5 wt.% PVDF) and their electrochemical performance for LIBs was explored regarding the effectiveness of the PAA binder. FV500 (PAA and PVDF) initially delivered higher discharge/charge capacities of 1046.23/771.692 mAhg−1 and 1051.21/661.849 mAhg−1 compared to FV600 and FV700 at the current densities of 100 mAg−1, respectively. The intrinsic defects and presence of oxygen vacancy along with high surface area and smaller particle sizes efficiently enhanced the ionic and electronic conductivities and delivered high discharge/charge capacities for FeVO4 as an anode for LIBs.

The roll-to-roll (R2R) continuous patterning of silver nanowire-polyvinylpyrrolidone (Ag NW-PVP) composite transparent conductive film (cTCF) is demonstrated in this work by means of slot-die coating followed by selective calendering. The Ag NWs were synthesized by the polyol method, and adequately washed to leave an appropriate amount of PVP to act as a capping agent and dispersant. The as-coated Ag NW-PVP composite film had low electronic conductivity due to the lack of percolation path, which was greatly improved by the calendering process. Moreover, the dispersion of Ag NWs was analyzed with addition of PVP in terms of density and molecular weight. The excellent dispersion led to uniform distribution of Ag NWs in a cTCF. The continuous patterning was conducted using an embossed pattern roll to perform selective calendering. To evaluate the capability of the calendering process, various line widths and spacing patterns were investigated. The minimum pattern dimensions achievable were determined to be a line width of 0.1 mm and a line spacing of 1 mm. Finally, continuous patterning using selective calendering was applied to the fabrication of a flexible heater and a resistive touch sensing panel as flexible electronic devices to demonstrate its versatility.

ObjectivesWe analyzed Korea's data privacy regime in the context of protecting and utilizing health and medical big data and tried to draw policy implications from the analyses.MethodsWe conducted comparative analyses of the legal and regulatory environments governing health and medical big data with a view to drawing policy implications for Korea. The legal and regulatory regimes considered include the following: the European Union, the United Kingdom, France, the United States, and Japan. We reviewed relevant statutory materials as well as various non-statutory materials and guidelines issued by public authorities. Where available, we also examined policy measures implemented by government agencies.ResultsIn this study, we investigated how various jurisdictions deal with legal and regulatory issues that may arise from the use of health and medical information with regard to the protection of data subjects' rights and the protection of personal information. We compared and analyzed various forms of legislation in various jurisdictions and also considered technical methods, such as de-identification. The main findings include the following: there is a need to streamline the relationship between the general data privacy regime and the regulatory regime governing health and medical big data; the regulatory and institutional structure for data governance should be more clearly delineated; and regulation should encourage the development of suitable methodologies for the de-identification of data and, in doing so, a principle-based and risk-based approach should be taken.ConclusionsFollowing our comparative legal analyses, implications were drawn. The main conclusion is that the relationship between the legal requirements imposed for purposes of personal information protection and the regulatory requirements governing the use of health and medical data is complicated and multi-faceted and, as such, their relationship should be more clearly streamlined and delineated.

This study suggested the design of type-variable electronic paper with multiple bottom electrode structures and experimentally investigated the process mechanism of the electrophoretic particle loading method (EPLM) as an electronic ink injection method. The type-variable electronic paper was achieved by constructing the multi-electrode structure that had a structure of four electrodes that can independently apply voltage to one cell. By injecting electronic ink that mixes two types of particles with opposite charges into an electrically neutral color (blue) fluid, we realized electronic paper with a single color, and we then measured the optical characteristics of the panel. We used the EPLM to prevent charged particles that have lost their charge from being injected into the e-paper by using an electric field. In order to confirm the color expression and transmittance control effect using the multi-electrode structure, we conducted reflectance measurement and transmittance measurement experiments. Our experiments confirmed that the expression of more than five colors was possible and that the transmittance was controllable to a minimum of 13.50% and a maximum of 71.18%. This study provides an attractive method to create e-paper as a new form outside the framework of existing e-paper technology.

Zinc oxide (ZnO) nanowires (NWs) are wide-bandgap semiconductors that absorb ultraviolet (UV) radiation. Various post-treatment processes have been studied to improve the optical properties of the as-grown ZnO NWs. Among them, Ag nanoparticles (NPs) effectively improved the optical properties on the surface of the ZnO NWs. In this study, ZnO NWs were synthesized via the hydrothermal synthesis method. ZnO NWs were decorated with Ag NPs on the surface of the ZnO NWs in a silver nitrate (AgNO3) aqueous solution by intense pulsed light (IPL) irradiation. Ag NPs were successfully decorated under the following conditions: aqueous AgNO3 solution of 100 nM, an energy of 1 J/cm2, and an exposure time of 8 ms. The responsivity and sensitivity of the ZnO NW UV photodetectors increased by 7.43 and 3.37 times, respectively. The IPL process makes it possible to decorate Ag NPs in a simple manner within an extremely short time.

While tomographic neuroimaging data is information rich, objective, and with high sensitivity in the study of brain diseases such as Alzheimer's disease (AD), its direct use in clinical practice and in regulated clinical trial (CT) still has many challenges. Taking CT as an example, unless the relevant policy and the perception of the primary outcome measures change, the need to construct univariate indices (out of the 3-D imaging data) to serve as CT's primary outcome measures will remain the focus of active research. More relevant to this current study, an overall global index that summarizes multiple complicated features from neuroimages should be developed in order to provide high diagnostic accuracy and sensitivity in tracking AD progression over time in clinical setting. Such index should also be practically intuitive and logically explainable to patients and their families. In this research, we propose a new visualization tool, derived from the manifold-based nonlinear dimension reduction of brain MRI features, to track AD progression over time. In specific, we investigate the locally linear embedding (LLE) method using a dataset from Alzheimer's Disease Neuroimaging Initiative (ADNI), which includes the longitudinal MRIs from 562 subjects. About 20% of them progressed to the next stage of dementia. Using only the baseline data of cognitively unimpaired (CU) and AD subjects, LLE reduces the feature dimension to two and a subject's AD progression path can be plotted in this low dimensional LLE feature space. In addition, the likelihood of being categorized to AD is indicated by color. This LLE map is a new data visualization tool that can assist in tracking AD progression over time.

Recently, a method of engineering the quantum states with a nonlinear interferometer was proposed to achieve precise state engineering for near-ideal single-mode operation and near-unity efficiency (L. Cui et al., Phys. Rev. A 102, 033718 (2020)), and the high-purity bi-photon states can be created without degrading brightness and collection efficiency. Here, we study the coarse or fine tunability of the nonlinear interference method to match constructive interference patterns into a transmission window of standard 100-GHz DWDM channels. The joint spectral intensity spectrum is measured for various conditions of the nonlinear interference effects. We show that the method has coarse- and fine-tuning ability while maintaining its high spectral purity. We expect that our results expand the usefulness of the nonlinear interference method. The photon-pair generation engineered via this method will be an excellent practical source of the quantum information process.

In this study, the microbiomes linked with the operational parameters in seven mesophilic full-scale AD plants mainly treating food waste (four plants) and sewage sludge (three plants) were analyzed. The results obtained indicated lower diversity and evenness of the microbial population in sludge digestion (SD) plants compared to food digestion (FD) plants. Candidatus Accumulibacter dominated (up to 42.1%) in SD plants due to microbial immigration from fed secondary sludge (up to 89%). Its potential activity in SD plants was correlated to H2 production, which was related to the dominance of hydrogenotrophic methanogens (Methanococcus). In FD plants, a balance between the hydrogenotrophic and methylotrophic pathways was found, while Flavobacterium and Levilinea played an important role during acidogenesis. Levilinea also expressed sensitivity to ammonia in FD plants. The substantial differences in hydraulic retention time (HRT), organic loading rate (OLR), and total ammonium nitrogen (TAN) among the studied FD plants did not influence the archaeal methane production pathway. In addition, the bacterial genera responsible for acetate production through syntrophy and homoacetogenesis (Smithella, Treponema) were present in all the plants studied.

An organic thin film back-gated transistor (OBGT) was fabricated and characterized. The gate electrode was printed on the back side of substrate, and the dielectric layer was omitted by substituting the dielectric layer with the polyimide (PI) film substrate. Roll-to-roll (R2R) gravure printing, doctor blading, and drop casting methods were used to fabricate the OBGT. The printed OBGT device shows better performance compared with an OTFT device based on dielectric layer of BaTiO3. Additionally, a calendering process enhanced the performance by a factor of 3 to 7 (mobility: 0.016 cm2/V·s, on/off ratio: 9.17×103). A bending test was conducted to confirm the flexibility and durability of the OBGT device. The results show the fabricated device endures 20000-cyclic motions. The realized OBGT device was successfully fabricated and working, which is meaningful for production engineering from the viewpoint of process development.

We report a conductometric nanoparticle biosensor array to address the significant variation of electrical property in nanomaterial biosensors due to the random network nature of nanoparticle thin-film. Indium oxide and silica nanoparticles (SNP) are assembled selectively on the multi-site channel area of the resistors using layer-by-layer self-assembly. To demonstrate enzymatic biosensing capability, glucose oxidase is immobilized on the SNP layer for glucose detection. The packaged sensor chip onto a ceramic pin grid array is tested using syringe pump driven feed and multi-channel I–V measurement system. It is successfully demonstrated that glucose is detected in many different sensing sites within a chip, leading to concentration dependent currents. The sensitivity has been found to be dependent on the channel length of the resistor, 4–12 nA/mM for channel lengths of 5–20 µm, while the apparent Michaelis-Menten constant is 20 mM. By using sensor array, analytical data could be obtained with a single step of sample solution feeding. This work sheds light on the applicability of the developed nanoparticle microsensor array to multi-analyte sensors, novel bioassay platforms, and sensing components in a lab-on-a-chip.

Tumor spheroids are considered a valuable three dimensional (3D) tissue model to study various aspects of tumor physiology for biomedical applications such as tissue engineering and drug screening as well as basic scientific endeavors, as several cell types can efficiently form spheroids by themselves in both suspension and adherent cell cultures. However, it is more desirable to utilize a 3D scaffold with tunable properties to create more physiologically relevant tumor spheroids as well as optimize their formation. In this study, bioactive spherical microgels supporting 3D cell culture are fabricated by a flow-focusing microfluidic device. Uniform-sized aqueous droplets of gel precursor solution dispersed with cells generated by the microfluidic device are photocrosslinked to fabricate cell-laden microgels. Their mechanical properties are controlled by the concentration of gel-forming polymer. Using breast adenocarcinoma cells, MCF-7, the effect of mechanical properties of microgels on their proliferation and the eventual spheroid formation was explored. Furthermore, the tumor cells are co-cultured with macrophages of fibroblasts, which are known to play a prominent role in tumor physiology, within the microgels to explore their role in spheroid formation. Taken together, the results from this study provide the design strategy for creating tumor spheroids utilizing mechanically-tunable microgels as 3D cell culture platform.

A fiber-based photon-pair source in the telecom C-band is suitable for quantum information science including quantum communications. Spontaneous four-wave mixing effects are known to create photon pairs that are slightly detuned from the pump wavelength only in the anomalous group-velocity-dispersion (GVD) regime. Here, we achieve high-quality photon-pair generation slightly detuned from the pump wavelength in the normal GVD regime through a dispersion shifted fiber, for the first time. The photon pairs in C-band exhibit strong temporal correlation with each other and excellent heralded anti-bunching property. This photon-pair generation scheme can be exploited as telecom-band quantum light sources for quantum information applications.

Subspace clustering, which detects all clusters in affine subspaces of a given high dimensional vector space, is used in various applications, including e-business. The performance and result of a subspace clustering algorithm highly depend on the parameter values the algorithm is tuned to execute. It may not be clear if the resultant clusters are indeed meaningful ones in a given dataset or if the result is just an artifact of the given parameter values. Although choosing the proper parameter values is crucial for both clustering quality and performance of the algorithm, there has been little research or discussion on this topic. In this paper, we propose a methodology for determining proper values of parameters in subspace clustering. Along with it, we validate our approach through experimental analysis, using various real-world datasets. The study can serve as a reference model for any subspace clustering experiment in which parameter setting is required to output clusters of quality.