Inference for Low-rank Models without Estimating the Rank

This paper studies the inference about linear functionals of high-dimensional low-rank matrices. While most existing inference methods would require consistent estimation of the true rank, our procedure is robust to rank misspecification, making it a promising approach in applications where rank estimation can be unreliable. We estimate the low-rank spaces using pre-specified weighting matrices, known as diversified projections. A novel statistical insight is that, unlike the usual statistical wisdom that overfitting mainly introduces additional variances, the over-estimated low-rank space also gives rise to a non-negligible bias due to an implicit ridge-type regularization. We develop a new inference procedure and show that the central limit theorem holds as long as the pre-specified rank is no smaller than the true rank. Empirically, we apply our method to the U.S. federal grants allocation data and test the existence of pork-barrel politics

Inference for Low-rank Completion without Sample Splitting with Application to Treatment Effect Estimation

This paper studies the inferential theory for estimating low-rank matrices. It also provides an inference method for the average treatment effect as an application. We show that the least square estimation of eigenvectors following the nuclear norm penalization attains the asymptotic normality. The key contribution of our method is that it does not require sample splitting. In addition, this paper allows dependent observation patterns and heterogeneous observation probabilities. Empirically, we apply the proposed procedure to estimating the impact of the presidential vote on allocating the U.S. federal budget to the states

A Case Study on Intelligent Service Design in Ubiquitous Computing

In this study we designed the killer services for the scene of labor learning in ubiquitous computing. To achieve this study, we have explored the unmet needs of teachers in the scene of labor learning and examined whether the unmet needs could be served by the resources and capabilities of ubiquitous computing. Then, we have crafted a detail killer services for the scene of labor learning proposed to serve educational users with the service architecture. The result of this study will be applied to develop new business model in ubiquitous computing as the basic research

Treatment of Axillary Osmidrosis Using a Subcutaneous Pulsed Nd-YAG Laser

BackgroundAxillary osmidrosis is characterized by an unpleasant odor, profuse sweating, and in some instances, staining of clothes that may socially and psychologically impair affected individuals. Various types of surgical procedures have been developed for the treatment of axillary osmidrosis. This study was undertaken to evaluate the effectiveness of subcutaneous pulsed neodymium: yttrium-aluminum-garnet (Nd-YAG) laser treatment for the treatment of axillary osmidrosis.MethodsTwenty-nine patients with axillary osmidrosis were included in this study. Patients were categorized according to the results of an axillary malodor grading system, and a subcutaneous pulsed Nd-YAG laser was applied to all patients. The treatment area for the appropriate distribution of laser energy was determined using the iodine starch test (Minor's test) against a grid pattern composed of 2×2 cm squares. The endpoint of exposure was 300 to 500 J for each grid, depending on the preoperative evaluation results. The results were evaluated by measurement of axillary malodor both pre- and postoperatively using the grading system and iodine starch test.ResultsThe average follow-up period was 12.8 months. Nineteen patients had a fair-to-good result and ten patients had poor results. The postoperative Minor's test demonstrated that there were remarkable improvements for patients with mild to moderate symptoms. Complications including superficial second degree burns (n=3) were treated in a conservative manner. A deep second degree burn (n=1) was treated by a surgical procedure.ConclusionsSubcutaneous pulsed Nd-YAG laser has many advantages and is an effective noninvasive treatment for mild to moderate axillary osmidrosis

Site Selective Laser Processing for Flexible and Wearable Electronics with 2D Materials and 2D-like Random Networks

Flexible and wearable electronics are envisioned as a future platform of electronics integrated into a variety of emerging technologies from sensing and monitoring to human-inspired applications. Among many fascinated flexible applications, displays are aggressively developing field of research and they are widely connected with transistor platform. Currently, the needs of people are being particular about for mobile phones, portable devices, and even televisions; they require new and more advanced displays. Therefore, the future displays should have high performances, such as low power consumption, ultra-high resolution, high frame rate and robust flexible platform. High-mobility thin film transistors will be a key enabling technology for achieving such performance by reducing the transistor size in the display’s active area. Also, they helps to increase aperture ratio, brightness, and frame rates and to decrease bus-line load power consumption.In this regard, 2D transition metal dichalcogenides have attracted much interest owing to their finite band gap values, rich excitonic dynamics, and even valley polarization (valleytronics) associated with the broken inversion symmetry. Among these 2D materials, molybdenum disulfide (MoS2) has been considered a channel material for high speed and/or flexible devices and a component material to improve the performance of conventional silicon devices. Furthermore, these layered semiconductors are emerging alternatives to silicon-based electronics. Despite their potentials in electronics and optoelectronics, reliable and stable processing methods are needed for successful transition to practical applications, especially for the flexible/wearable electronics used flexible materials with a low thermal budget (< 200 °C). Typically, used flexible materials cannot be applied conventional high thermal processes, which affect the entire panel including unwanted areas where the high thermal process should be excluded.For the process having the critical limitations of the flexible/wearable applications, the many features of laser are exactly appropriate; the laser is spatially local selective, air-stable, and widely tunable by varying the duration and intensity of laser irradiation. Moreover, laser process can be digitally controlled by the computer with programmable software. In this dissertation, the proposed approaches (laser annealing, direct laser writing, laser welding, and interference lithography) represent a powerful means to realize high performance flexible devices based 2D materials, especially for MoS2.First, I demonstrate that mechanically flexible and optically transparent (more than 81% transmittance in visible wavelength) multilayered MoS2 thin-film transistors (TFTs) in which the source/drain electrodes are selectively annealed using picosecond laser achieve the enhancement of device performance without plastic deformation, such as boosted mobility, increased output resistance, and decreased subthreshold swing. Numerical thermal simulation for the temperature distribution, transmission electron microscopy (TEM) analysis, current-voltage measurements, and contact-free mobility extracted from the Y-function method (YFM) enable understanding of the compatibility and the effects of pulsed laser annealing process; the enhanced performance originated not only from a decrease in the Schottky barrier effect at the contact, but also an improvement of the channel interface.Second, through laser direct writing (LDW) method, arbitrary fine patterns are produced for the electrodes as well as defining the channel of TFTs. Also, LDW with ink-jet printing shows the possibility and the potential for the future of flexible/wearable electronics as more versatile process. In addition, interference lithography using phase shift mask allows making periodic nano-scale features, readily.Furthermore, laser process is also applied to the welding for fabricating mechanically robust and electrically attractive 2D-like random networks. The laser welding is compatible with cost-effective solution process and good for the flexible applications. After the laser welding, the sheet resistance of 2D-like networks created by silver nanowires is significantly improved. Note that the best improvement is around 55 times without any degradation of the electrical performance during cycling bending test.These various outcomes from the experiments indicate that the site selective laser process can open up opportunities to fabrication of the electrical devices on flexible platforms

Site Selective Laser Processing for Flexible and Wearable Electronics with 2D Materials and 2D-like Random Networks

Flexible and wearable electronics are envisioned as a future platform of electronics integrated into a variety of emerging technologies from sensing and monitoring to human-inspired applications. Among many fascinated flexible applications, displays are aggressively developing field of research and they are widely connected with transistor platform. Currently, the needs of people are being particular about for mobile phones, portable devices, and even televisions; they require new and more advanced displays. Therefore, the future displays should have high performances, such as low power consumption, ultra-high resolution, high frame rate and robust flexible platform. High-mobility thin film transistors will be a key enabling technology for achieving such performance by reducing the transistor size in the display’s active area. Also, they helps to increase aperture ratio, brightness, and frame rates and to decrease bus-line load power consumption.In this regard, 2D transition metal dichalcogenides have attracted much interest owing to their finite band gap values, rich excitonic dynamics, and even valley polarization (valleytronics) associated with the broken inversion symmetry. Among these 2D materials, molybdenum disulfide (MoS2) has been considered a channel material for high speed and/or flexible devices and a component material to improve the performance of conventional silicon devices. Furthermore, these layered semiconductors are emerging alternatives to silicon-based electronics. Despite their potentials in electronics and optoelectronics, reliable and stable processing methods are needed for successful transition to practical applications, especially for the flexible/wearable electronics used flexible materials with a low thermal budget (< 200 °C). Typically, used flexible materials cannot be applied conventional high thermal processes, which affect the entire panel including unwanted areas where the high thermal process should be excluded.For the process having the critical limitations of the flexible/wearable applications, the many features of laser are exactly appropriate; the laser is spatially local selective, air-stable, and widely tunable by varying the duration and intensity of laser irradiation. Moreover, laser process can be digitally controlled by the computer with programmable software. In this dissertation, the proposed approaches (laser annealing, direct laser writing, laser welding, and interference lithography) represent a powerful means to realize high performance flexible devices based 2D materials, especially for MoS2.First, I demonstrate that mechanically flexible and optically transparent (more than 81% transmittance in visible wavelength) multilayered MoS2 thin-film transistors (TFTs) in which the source/drain electrodes are selectively annealed using picosecond laser achieve the enhancement of device performance without plastic deformation, such as boosted mobility, increased output resistance, and decreased subthreshold swing. Numerical thermal simulation for the temperature distribution, transmission electron microscopy (TEM) analysis, current-voltage measurements, and contact-free mobility extracted from the Y-function method (YFM) enable understanding of the compatibility and the effects of pulsed laser annealing process; the enhanced performance originated not only from a decrease in the Schottky barrier effect at the contact, but also an improvement of the channel interface.Second, through laser direct writing (LDW) method, arbitrary fine patterns are produced for the electrodes as well as defining the channel of TFTs. Also, LDW with ink-jet printing shows the possibility and the potential for the future of flexible/wearable electronics as more versatile process. In addition, interference lithography using phase shift mask allows making periodic nano-scale features, readily.Furthermore, laser process is also applied to the welding for fabricating mechanically robust and electrically attractive 2D-like random networks. The laser welding is compatible with cost-effective solution process and good for the flexible applications. After the laser welding, the sheet resistance of 2D-like networks created by silver nanowires is significantly improved. Note that the best improvement is around 55 times without any degradation of the electrical performance during cycling bending test.These various outcomes from the experiments indicate that the site selective laser process can open up opportunities to fabrication of the electrical devices on flexible platforms

Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

Axons in central nervous system (CNS) do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif) ligand 2 (CCL2) seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs). Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries

The Relationship Between Healthcare Information System And Cost In Hospital

This study was purposed to study the relationship between healthcare information system (HIS) and cost in hospital. It also analyzed which organizational factors affect the adoption of information system in hospitals. The study included 577 hospitals in the statistical analysis. The HIS was measured by three indicators, which is based on the number of application systems in three core hospital functions (administration, management, and clinical). American Hospital Association and Dorenfest IHDS were merged to create sample data. Structural equation modeling was applied to estimate the parameters of the model. HIS is negatively associated with the total expense. However, it was not statistically significant. The internal variables of hospitals such as location, size, and system hospital variables were significantly related to the extent of HIS adoption. © Springer-Verlag London Limited 2012

Morphological Analysis of PSMA/PEI Core–Shell Nanoparticles Synthesized by Soap-Free Emulsion Polymerization

Emulsion polymerization presents the disadvantage that the physical properties of polymer particles are altered by surfactant adsorption. Therefore, in the soap-free emulsion polymerization method, a hydrophilic initiator is utilized while inducing repulsion among particles on the polymer particle surface, resulting in stable polymer particle production. In this study, we developed a methodology wherein spherical and uniform poly(styrene-co-maleic anhydride) (PSMA)/polyethyleneimine (PEI) core–shell nanoparticles were prepared. Further, their morphology was analyzed. During PSMA polymerization, the addition of up to 30% maleic anhydride (MA) resulted in stable polymerization. In PSMA/PEI nanoparticle fabrication, the number of reactants increased with increased initial monomer feed amounts; consequently, the particle size increased, and as the complete monomer consumption time increased, the particle distribution widened. The styrene (St) copolymer acted as a stabilizer, reducing particle size and narrowing particle distribution. Furthermore, the monomers were more rapidly consumed at high initiator concentrations, irrespective of the initiator used, resulting in increased particle stability and narrowed particle distribution. The shell thickness and particle size were PEI feed ratio dependent, with 0.08 being the optimal PEI-to-MA ratio. The fabricated nanoparticles possess immense potential for application in environmental science and in chemical and health care industries

Construction of SARS-CoV-2 virus-like particles in plant

The pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused a public health emergency, and research on the development of various types of vaccines is rapidly progressing at an unprecedented development speed internationally. Some vaccines have already been approved for emergency use and are being supplied to people around the world, but there are still many ongoing efforts to create new vaccines. Virus-like particles (VLPs) enable the construction of promising platforms in the field of vaccine development. Here, we demonstrate that non-infectious SARS-CoV-2 VLPs can be successfully assembled by co-expressing three important viral proteins membrane (M), envelop (E) and nucleocapsid (N) in plants. Plant-derived VLPs were purified by sedimentation through a sucrose cushion. The shape and size of plant-derived VLPs are similar to native SARS-CoV-2 VLPs without spike. Although the assembled VLPs do not have S protein spikes, they could be developed as formulations that can improve the immunogenicity of vaccines including S antigens, and further could be used as platforms that can carry S antigens of concern for various mutations