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1.
Nat Nanotechnol ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956320

ABSTRACT

Neuromodulation technologies are crucial for investigating neuronal connectivity and brain function. Magnetic neuromodulation offers wireless and remote deep brain stimulations that are lacking in optogenetic- and wired-electrode-based tools. However, due to the limited understanding of working principles and poorly designed magnetic operating systems, earlier magnetic approaches have yet to be utilized. Furthermore, despite its importance in neuroscience research, cell-type-specific magnetic neuromodulation has remained elusive. Here we present a nanomaterials-based magnetogenetic toolbox, in conjunction with Cre-loxP technology, to selectively activate genetically encoded Piezo1 ion channels in targeted neuronal populations via torque generated by the nanomagnetic actuators in vitro and in vivo. We demonstrate this cell-type-targeting magnetic approach for remote and spatiotemporal precise control of deep brain neural activity in multiple behavioural models, such as bidirectional feeding control, long-term neuromodulation for weight control in obese mice and wireless modulation of social behaviours in multiple mice in the same physical space. Our study demonstrates the potential of cell-type-specific magnetogenetics as an effective and reliable research tool for life sciences, especially in wireless, long-term and freely behaving animals.

2.
Adv Sci (Weinh) ; : e2402934, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38859618

ABSTRACT

Thermoelectric devices have received significant attention because of their potential for sustainable energy recovery. In these devices, a thermal design that optimizes heat transfer and dissipation is crucial for maximizing the power output. Heat dissipation generally requires external active or passive cooling devices, which often suffer from inevitable heat loss and heavy systems. Herein, the design of heat-sink integrated thermoelectric legs is proposed to enhance heat dissipation without external cooling devices, realized by finite element model simulation and 3D printing of ternary silver chalcogenide-based thermoelectric materials. Owing to the self-induced surface charges of the synthesized AgBiSe2 (n-type) and AgSbTe2 (p-type) particles, these particle-based colloidal inks exhibited high viscoelasticity, which enables the creation of complex heat-dissipation architectures via 3D printing. Power generators made from 3D-printed heat-dissipating legs exhibit higher temperature differences and output power than traditional cuboids, offering a new strategy for enhancing thermoelectric power generation.

3.
Plants (Basel) ; 13(11)2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38891384

ABSTRACT

Rapeseed (Brassica napus L.) holds significant commercial value as one of the leading oil crops, with its agronomic features and oil quality being crucial determinants. In this investigation, 73,226 single nucleotide polymorphisms (SNPs) across 95 rapeseed mutant lines induced by gamma rays, alongside the original cultivar ('Tamra'), using genotyping-by-sequencing (GBS) analysis were examined. This study encompassed gene ontology (GO) analysis and a genomewide association study (GWAS), thereby concentrating on agronomic traits (e.g., plant height, ear length, thousand-seed weight, and seed yield) and oil traits (including fatty acid composition and crude fat content). The GO analysis unveiled a multitude of genes with SNP variations associated with cellular processes, intracellular anatomical structures, and organic cyclic compound binding. Through GWAS, we detected 320 significant SNPs linked to both agronomic (104 SNPs) and oil traits (216 SNPs). Notably, two novel candidate genes, Bna.A05p02350D (SFGH) and Bna.C02p22490D (MDN1), are implicated in thousand-seed weight regulation. Additionally, Bna.C03p14350D (EXO70) and Bna.A09p05630D (PI4Kα1) emerged as novel candidate genes associated with erucic acid and crude fat content, respectively. These findings carry implications for identifying superior genotypes for the development of new cultivars. Association studies offer a cost-effective means of screening mutants and selecting elite rapeseed breeding lines, thereby enhancing the commercial viability of this pivotal oil crop.

4.
Diagnostics (Basel) ; 14(12)2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38928640

ABSTRACT

INTRODUCTION: In 2019, mild vestibular function deficiency in elder populations was defined as presbyvestibulopathy (PVP) by the Classification Committee of the Bárány Society. The diagnostic criteria include tests for low-, mid-, and high-frequency vestibular function, represented by caloric testing, rotary chair testing, and head impulse testing, respectively. However, there is still a lack of large-scale reports supporting the relationship between vestibular function tests (VFTs) and aging. In this study, we evaluated whether each test is correlated with aging in the elderly population aged over 50. METHODS: This study retrospectively enrolled 1043 subjects from a single university hospital database after excluding those with unilateral and bilateral vestibulopathy, central dizziness, and acute dizziness. Enrolled subjects had caloric canal paresis <20%, vHIT lateral canal gain >0.6, vHIT interaural difference <0.3, and age >50 years old. RESULTS: Significant negative correlations with age were identified in the vHIT (p < 0.001) and rotary chair test (RCT) 1.0 Hz gain (p = 0.030). However, the caloric test (p = 0.739 and 0.745 on the left and right sides, respectively) and RCT 0.12 Hz gain (p = 0.298) did not show a significant correlation with age. A total of 4.83% of subjects aged 70 years or older showed sub-normal vHIT gain that met the criteria of PVP, whereas only 0.50% of subjects aged 60 to 69 did. The prevalence of sub-normal caloric test results, however, was not significantly different between the two age groups (21.55% in the 60-69 age group and 26.59% in the >70 age group). CONCLUSIONS: The high-frequency range vestibular function seems vulnerable to aging, and this is more discernible at age >70 years. The weak correlation between age and low-frequency vestibular function tests, such as the caloric test and low-frequency rotary chair testing, suggests the need to revisit the diagnostic criteria for PVP.

5.
ACS Appl Mater Interfaces ; 16(20): 26580-26589, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38733565

ABSTRACT

Cellulose nanocrystals (CNCs) are currently of great interest for many applications, such as energy storage and nanocomposites, because of their natural abundance. A number of carbonization studies have reported abnormal graphitization behavior of CNCs, although cellulose is generally known as a precursor for hard carbon (nongraphitizable carbon). Herein, we report a spray-freeze-drying (SFD) method for CNCs and a subsequent carbonization study to ascertain the difference in the structural development between the amorphous and crystalline phases. The morphological observation by high-resolution transmission electron microscopy of the carbonized SFD-CNC clearly shows that the amorphous and crystalline phases of CNC are attributed to the formation of hard and soft carbon, respectively. The results of a reactive molecular dynamics (RMD) study also show that the amorphous cellulose phase leads to the formation of fewer carbon ring structures, indicative of hard carbon. In contrast, the pristine crystalline cellulose phase has a higher density and thermal stability, resulting in limited molecular relaxation and the formation of a highly crystalline graphitic structure (soft carbon).

6.
Immunology ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778445

ABSTRACT

Cytokines of the common-γ receptor chain (γc) family are crucial for T-cell differentiation and dysregulation of γc cytokine pathways is involved in the pathogenesis of autoimmune diseases. There is increasing evidence that the availability of the γc receptor (CD132) for the associated receptor chains has implications for T-cell functions. Here we studied the influence of differential γc expression on the expression of the IL-2Rα (CD25), the IL-7Rα (CD127) and the differentiation of activated naïve T cells. We fine-tuned the regulation of γc expression in human primary naïve T cells by lentiviral transduction using small hairpin (sh)RNAs and γc cDNA. Differential γc levels were then analysed for effects on T-cell phenotype and function after activation. Differential γc expression markedly affected IL-2Rα and IL-7Rα expression on activated naïve T cells. High γc expression (γc-high) induced significantly higher expression of IL-2Rα and re-expression of IL-7Rα after activation. Inhibition of γc caused lower IL-2Rα/IL-7Rα expression and impaired proliferation of activated naïve T cells. In contrast, γc-high T cells secreted significantly higher concentrations of effector cytokines (i.e., IFN-γ, IL-6) and showed higher cytokine-receptor induced STAT5 phosphorylation during initial stages as well as persistently higher pSTAT1 and pSTAT3 levels after activation. Finally, accelerated transition towards a CD45RO expressing effector/memory phenotype was seen especially for CD4+ γc-high naïve T cells. These results suggested that high expression of γc promotes expression of IL-2Rα and IL-7Rα on activated naïve T cells with significant effects on differentiation and effector cytokine expression.

7.
Mol Med Rep ; 30(1)2024 07.
Article in English | MEDLINE | ID: mdl-38785149

ABSTRACT

Promotion of myoblast differentiation by activating mitochondrial biogenesis and protein synthesis signaling pathways provides a potential alternative strategy to balance energy and overcome muscle loss and muscle disorders. Saururus chinensis (Lour.) Baill. extract (SCE) has been used extensively as a traditional herbal medicine and has several physiological activities, including anti­asthmatic, anti­oxidant, anti­inflammatory, anti­atopic, anticancer and hepatoprotective properties. However, the effects and mechanisms of action of SCE on muscle differentiation have not yet been clarified. In the present study, it was investigated whether SCE affects skeletal muscle cell differentiation through the regulation of mitochondrial biogenesis and protein synthesis in murine C2C12 myoblasts. The XTT colorimetric assay was used to determine cell viability, and myosin heavy chain (MyHC) levels were determined using immunocytochemistry. SCE was applied to C2C12 myotube at different concentrations (1, 5, or 10 ng/ml) and times (1,3, or 5 days). Reverse transcription­quantitative PCR and western blotting were used to analyze the mRNA and protein expression change of factors related to differentiation, mitochondrial biogenesis and protein synthesis. Treatment of C2C12 cells with SCE at 1,5, and 10 ng/ml did not affect cell viability. SCE promoted C2C12 myotube formation and significantly increased MyHC expression in a concentration­ and time­dependent manner. SCE significantly increased the mRNA and protein expression of muscle differentiation­specific markers, such as MyHC, myogenic differentiation 1, myogenin, Myogenic Factor 5, and ß­catenin, mitochondrial biosynthesis­related factors, such as peroxisome proliferator­activated receptor­gamma coactivator­1α, nuclear respirator factor­1, AMP­activated protein kinase phosphorylation, and histone deacetylase 5 and AKT/mTOR signaling factors related to protein synthesis. SCE may prevent skeletal muscle dysfunction by enhancing myoblast differentiation through the promotion of mitochondrial biogenesis and protein synthesis.


Subject(s)
Cell Differentiation , Organelle Biogenesis , Plant Extracts , Proto-Oncogene Proteins c-akt , Saururaceae , Signal Transduction , TOR Serine-Threonine Kinases , Animals , Mice , Cell Differentiation/drug effects , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Plant Extracts/pharmacology , Cell Line , Saururaceae/chemistry , Cell Survival/drug effects , Myoblasts/metabolism , Myoblasts/drug effects , Myoblasts/cytology , Mitochondria/metabolism , Mitochondria/drug effects , Muscle Development/drug effects , Muscle Fibers, Skeletal/metabolism , Muscle Fibers, Skeletal/drug effects , Muscle Fibers, Skeletal/cytology , Myosin Heavy Chains/metabolism , Myosin Heavy Chains/genetics , Muscle, Skeletal/metabolism , Muscle, Skeletal/drug effects , Muscle, Skeletal/cytology
8.
Exp Ther Med ; 27(5): 208, 2024 May.
Article in English | MEDLINE | ID: mdl-38590570

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by articular cartilage destruction, bone destruction and synovial hyperplasia. It has been suggested that Vigeo, a mixture of Eleutherococcus senticosus, Achyranthes japonica and Atractylodes japonica fermented with Korean nuruk, has an anti-osteoporotic effect in a mouse model of inflammation-mediated bone loss. The present study evaluated the therapeutic effects of Vigeo in RA using a collagen-induced arthritis (CIA) mouse model. DBA/1J mice were immunized with bovine type II collagen on days 0 and 21 and Vigeo was administered daily for 20 days beginning the day after the second type II collagen injection. The mice were sacrificed on day 42 and the joint tissues were anatomically separated and subjected to micro computed tomography and histological analyses. In addition, the serum levels of TNF-α, IL-6 and IL-1ß were determined by enzyme-linked immunosorbent assays. CIA in DBA/1J mice caused symptoms of RA, such as joint inflammation, cartilage destruction and bone erosion. Treatment of CIA mice with Vigeo markedly decreased the symptoms and cartilage pathology. In addition, radiological and histological analyses showed that Vigeo attenuated bone and cartilage destruction. The serum TNF-α, IL-6 and IL-1ß levels following oral Vigeo administration were also reduced when compared with those in CIA mice. The present study revealed that Vigeo suppressed arthritis symptoms in a CIA-RA mouse model, including bone loss and serum levels of TNF-α, IL-6 and IL-1ß.

9.
bioRxiv ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38562848

ABSTRACT

Inhibitory neurons are diverse across the brain, but for the visual system we lack the ability to functionally classify these neurons under complex natural stimuli. Here we take the approach of classifying retinal amacrine cell responses to natural scenes using optical recording and an interpretable neural network model. We fit mouse amacrine cell responses to a two-layer convolutional neural network model of a class shown previously to accurately capture salamander ganglion cell responses to natural scenes. Using an approach from interpretable machine learning, we determined for each stimulus the model interneurons that generated each amacrine response, analogous to the set of bipolar cells that target the amacrine population. From this analysis we clustered amacrine cells not by their natural scene responses, but by the model presynaptic neurons that constructed those responses, conservatively finding approximately seven groups by this approach. By analyzing the set of model presynaptic input neurons for each amacrine cluster, we find that distributed rather than dedicated inputs generate natural scene responses for different amacrine cell types. Additional analyses revealed distinct transient and sustained modes exhibited by the network during the response to simple flashes. These results give insight into the computational structure of how the diverse amacrine cell population responds to natural scenes, and generate multiple quantitative hypotheses for how synaptic inputs generate those responses.

10.
ACS Appl Mater Interfaces ; 16(14): 17683-17691, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38531014

ABSTRACT

Porous thermoelectric materials offer exciting prospects for improving the thermoelectric performance by significantly reducing the thermal conductivity. Nevertheless, porous structures are affected by issues, including restricted enhancements in performance attributed to decreased electronic conductivity and degraded mechanical strength. This study introduces an innovative strategy for overcoming these challenges using porous Bi0.4Sb1.6Te3 (BST) by combining porous structuring and interface engineering via atomic layer deposition (ALD). Porous BST powder was produced by selectively dissolving KCl in a milled mixture of BST and KCl; the interfaces were engineered by coating ZnO films through ALD. This novel architecture remarkably reduced the thermal conductivity owing to the presence of several nanopores and ZnO/BST heterointerfaces, promoting efficient phonon scattering. Additionally, the ZnO coating mitigated the high resistivity associated with the porous structure, resulting in an improved power factor. Consequently, the ZnO-coated porous BST demonstrated a remarkable enhancement in thermoelectric efficiency, with a maximum zT of approximately 1.53 in the temperature range of 333-353 K, and a zT of 1.44 at 298 K. Furthermore, this approach plays a significant role in enhancing the mechanical strength, effectively mitigating a critical limitation of porous structures. These findings open new avenues for the development of advanced porous thermoelectric materials and highlight their potential for precise interface engineering through the ALD.

11.
Nanomaterials (Basel) ; 14(6)2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38535635

ABSTRACT

Organic-inorganic hybrid dielectric nanomaterials are vital for OTFT applications due to their unique combination of organic dielectric and inorganic properties. Despite the challenges in preparing stable titania (TiO2) nanoparticles, we successfully synthesized colloidally stable organic-inorganic (O-I) TiO2 hybrid nanoparticles using an amphiphilic polymer as a stabilizer through a low-temperature sol-gel process. The resulting O-I TiO2 hybrid sols exhibited long-term stability and formed a high-quality dielectric layer with a high dielectric constant (κ) and minimal leakage current density. We also addressed the effect of the ethylene oxide chain within the hydrophilic segment of the amphiphilic polymer on the dielectric properties of the coating film derived from O-I TiO2 hybrid sols. Using the O-I TiO2 hybrid dielectric layer with excellent insulating properties enhanced the electrical performance of the gate dielectrics, including superior field-effect mobility and stable operation in OTFT devices. We believe that this study provides a reliable method for the preparation of O-I hybrid TiO2 dielectric materials designed to enhance the operational stability and electrical performance of OTFTs.

12.
Nat Commun ; 15(1): 1772, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413568

ABSTRACT

Current soft neural probes are still operated by bulky, rigid electronics mounted to a body, which deteriorate the integrity of the device to biological systems and restrict the free behavior of a subject. We report a soft, conformable neural interface system that can monitor the single-unit activities of neurons with long-term stability. The system implements soft neural probes in the brain, and their subsidiary electronics which are directly printed on the cranial surface. The high-resolution printing of liquid metals forms soft neural probes with a cellular-scale diameter and adaptable lengths. Also, the printing of liquid metal-based circuits and interconnections along the curvature of the cranium enables the conformal integration of electronics to the body, and the cranial circuit delivers neural signals to a smartphone wirelessly. In the in-vivo studies using mice, the system demonstrates long-term recording (33 weeks) of neural activities in arbitrary brain regions. In T-maze behavioral tests, the system shows the behavior-induced activation of neurons in multiple brain regions.


Subject(s)
Electronics , Neurons , Animals , Mice , Neurons/physiology , Brain/physiology , Skull/diagnostic imaging , Metals , Printing, Three-Dimensional
13.
J Cell Biochem ; 125(2): e30518, 2024 02.
Article in English | MEDLINE | ID: mdl-38224182

ABSTRACT

Excessive bone-resorbing osteoclast activity during bone remodeling is a major feature of bone diseases, such as osteoporosis. Therefore, the inhibition of osteoclast formation and bone resorption can be an effective therapeutic target for various bone diseases. Gryllus biomaculatus (GB) has recently been approved as an alternative food source because of its high nutritional value and environmental sustainability. Traditionally, GB has been known to have various pharmacological properties, including antipyretic and blood pressure-lowering activity, and it has recently been reported to have various biological activities, including protective effects against inflammation, oxidative stress, insulin resistance, and alcohol-induced liver injury. However, the effect of GB on osteoclast differentiation and bone metabolism has not yet been demonstrated. In this study, we confirmed the inhibitory effect of GB extract (GBE) on the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation. To determine the effect of GBE on RANKL-induced osteoclast differentiation and function, we performed TRAP and F-actin staining, as well as a bone-resorbing assay. The intracellular mechanisms of GBE responsible for the regulation of osteoclastogenesis were revealed by Western blot analysis and quantitative real-time polymerase chain reaction. We investigated the relationship between GBE and expression of osteoclast-specific molecules to further elucidate the underlying mechanisms. It was found that GBE significantly suppressed osteoclastogenesis by decreasing the phosphorylation of Akt, p38, JNK, and ERK, as well as Btk-PLCγ2 signaling, in pathways involved in early osteoclastogenesis as well as through the subsequent suppression of c-Fos, NFATc1, and osteoclastogenesis-specific marker genes. Additionally, GBE inhibited the formation of F-actin ring-positive osteoclasts and bone resorption activity of mature osteoclasts. Our findings suggest that GBE is a potential functional food and therapeutic candidate for bone diseases involving osteoclasts.


Subject(s)
Bone Resorption , Osteoclasts , RANK Ligand , Humans , Actins/metabolism , Bone Resorption/drug therapy , Cell Differentiation , Ligands , NF-kappa B/metabolism , NFATC Transcription Factors/metabolism , Osteoclasts/metabolism , RANK Ligand/antagonists & inhibitors , RANK Ligand/metabolism
14.
BMC Health Serv Res ; 23(1): 1334, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38041081

ABSTRACT

BACKGROUND: The recent rising health spending intrigued efficiency and cost-based performance measures. However, mortality risk adjustment methods are still under consideration in cost estimation, though methods specific to cost estimate have been developed. Therefore, we aimed to compare the performance of diagnosis-based risk adjustment methods based on the episode-based cost to utilize in efficiency measurement. METHODS: We used the Health Insurance Review and Assessment Service-National Patient Sample as the data source. A separate linear regression model was constructed within each Major Diagnostic Category (MDC). Individual models included explanatory (demographics, insurance type, institutional type, Adjacent Diagnosis Related Group [ADRG], diagnosis-based risk adjustment methods) and response variables (episode-based costs). The following risk adjustment methods were used: Refined Diagnosis Related Group (RDRG), Charlson Comorbidity Index (CCI), National Health Insurance Service Hierarchical Condition Categories (NHIS-HCC), and Department of Health and Human Service-HCC (HHS-HCC). The model accuracy was compared using R-squared (R2), mean absolute error, and predictive ratio. For external validity, we used the 2017 dataset. RESULTS: The model including RDRG improved the mean adjusted R2 from 40.8% to 45.8% compared to the adjacent DRG. RDRG was inferior to both HCCs (RDRG adjusted R2 45.8%, NHIS-HCC adjusted R2 46.3%, HHS-HCC adjusted R2 45.9%) but superior to CCI (adjusted R2 42.7%). Model performance varied depending on the MDC groups. While both HCCs had the highest explanatory power in 12 MDCs, including MDC P (Newborns), RDRG showed the highest adjusted R2 in 6 MDCs, such as MDC O (pregnancy, childbirth, and puerperium). The overall mean absolute errors were the lowest in the model with RDRG ($1,099). The predictive ratios showed similar patterns among the models regardless of the  subgroups according to age, sex, insurance type, institutional type, and the upper and lower 10th percentiles of actual costs. External validity also showed a similar pattern in the model performance. CONCLUSIONS: Our research showed that either NHIS-HCC or HHS-HCC can be useful in adjusting comorbidities for episode-based costs in the process of efficiency measurement.


Subject(s)
Insurance, Health , Risk Adjustment , Female , Humans , Infant, Newborn , Risk Adjustment/methods , Comorbidity , Diagnosis-Related Groups , Linear Models
15.
J Multidiscip Healthc ; 16: 4163-4172, 2023.
Article in English | MEDLINE | ID: mdl-38146358

ABSTRACT

Background: During COVID-19, nursing students experienced variations in on-site clinical practice, such as a combination of on-site and non-face-to-face clinical practice. Although on-site clinical practice is critical for increasing nurses' clinical self-efficacy and developing professional nursing values, there is a lack of knowledge that reflects the current clinical practice environment. Aim: To examine the relationship between on-site clinical practice, nursing professional values, and nursing clinical self-efficacy during the COVID-19 pandemic. Methods: This study is a cross-sectional correlational study design. Demographic characteristics, on-site clinical practice, nursing professional values, and nursing clinical self-efficacy were assessed using an online survey from October 3, 2022, to November 6, 2022. Data were analyzed using descriptive statistics, ANOVA, t-test, Pearson's correlation coefficient, and multiple regression. Results: Of the 86 participants, 18 (20.9%) were male and 68 (79.1%) were female. The duration of the participants' average participation in on-site clinical practice was 39.67 days (61.04%). Nursing professional values significantly influenced clinical self-efficacy (ß=0.379, p<0.001). However, on-site clinical practice was not significantly related to clinical self-efficacy (ß=0.051, p=0.611). In terms of nursing clinical self-efficacy, measuring blood glucose had the highest score. On the other hand, establishing and maintaining intravenous catheters had the lowest scores. Conclusion: Nursing students' professional values were significantly associated with nursing clinical self-efficacy; however, the extent of involvement in on-site clinical practice during the pandemic did not have a significant impact on nursing clinical self-efficacy. Given that this study focused on a single university, it is imperative to replicate this research using diverse samples in the future. In addition, there is a need to establish a range of teaching and learning approaches for clinical practice, including simulation, online learning, and the use of state-of-the-art technology for faculty-student feedback strategies, in anticipation of the need for alternative practices.

16.
Sci Rep ; 13(1): 20460, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37993479

ABSTRACT

There has been significant research focused on the development of stretchable materials that can provide a large area with minimal material usage for use in solar cells and displays. However, most materials exhibit perpendicular shrinkage when stretched, which is particularly problematic for polymer-based substrates commonly used in stretchable devices. To address this issue, biaxial strain-controlled substrates have been proposed as a solution to increase device efficiency and conserve material resources. In this study, we present the design and fabrication of a biaxial strain-controlled substrate with a re-entrant honeycomb structure and a negative Poisson's ratio. Using a precisely machined mold with a shape error of less than 0.15%, we successfully fabricated polydimethylsiloxane substrates with a 500 µm thick re-entrant honeycomb structure, resulting in a 19.1% reduction in perpendicular shrinkage. This improvement translates to a potential increase in device efficiency by 9.44% and an 8.60% reduction in material usage for substrate fabrication. We demonstrate that this design and manufacturing method can be applied to the fabrication of efficient stretchable devices, such as solar cells and displays.

17.
J Korean Med Sci ; 38(43): e337, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37935164

ABSTRACT

BACKGROUND: A methodology for comprehensively and reasonably measuring the burden of disease due to adverse events has yet to be clearly established. In this study, a new and systematic method for measuring the burden of disease due to adverse events was tested by utilizing the results of a medical record review, which is commonly used as a gold standard. METHODS: Using the characteristics of preventable adverse events identified in the 2019 Patient Safety Incidents Inquiry (PSII), conducted to monitor the level of patient safety in Korea accurately, the resulting disability-adjusted life years (DALYs) and economic costs were estimated. DALYs were calculated as the sum of the years lived with a disability for patients who suffered permanent disability, or more, due to preventable adverse events, and the years of life lost due to premature mortality was calculated for patients who died due to preventable adverse events. The economic cost was calculated using the main diagnostic codes of patients who suffered preventable adverse events, identified as prolonged hospitalization in PSII, and the average medical cost by disease category and age group. RESULTS: Estimates of DALYs due to preventable adverse events were 1,114.4 DALYs per 100,000 population for the minimum standard and 1,658.5 DALYs per 100,000 population for the maximum standard. Compared to the 2015 Korea Burden of Disease results, the ranking of DALYs due to preventable adverse events was sixth for the minimum standard and third for the maximum standard. The annual medical cost of adverse events in 2016 was estimated to be approximately Korean Republic Won (KRW) 870 billion (700 million US dollars). Medical expenses due to preventable adverse events were calculated to be approximately KRW 150 billion (120 million US dollars) as a minimum standard and approximately KRW 300 billion (240 million US dollars) as a maximum standard. CONCLUSION: If this more standard method of systematically calculating the disease burden due to adverse events is used, it will be possible to compare the size of the patient safety problem with that of other diseases. The results of this study indicate that we still need to pay more attention to the issue of patient safety.


Subject(s)
Disabled Persons , Patient Safety , Humans , Quality-Adjusted Life Years , Cross-Sectional Studies , Cost of Illness
18.
Materials (Basel) ; 16(22)2023 Nov 16.
Article in English | MEDLINE | ID: mdl-38005120

ABSTRACT

We studied the influence of the ethylenediaminetetraacetic acid (EDTA) content used as combustion fuel when fabricating nickel oxide (NiO) nanocatalysts via solution combustion synthesis, as well as the growth behavior of carbon nanotubes (CNTs) using this catalyst. Nickel nitrate hexahydrate (Ni(NO3)2∙6H2O) was used as the metal precursor (an oxidizer), and the catalysts were synthesized by adjusting the molar ratio of fuel (EDTA) to oxidizer in the range of 1:0.25 to 2.0. The results of the crystal structure analysis showed that as the EDTA content increased beyond the chemical stoichiometric balance with Ni(NO3)2∙6H2O (F/O = 0.25), the proportion of Ni metal within the catalyst particles decreased, and only single-phase NiO was observed. Among the synthesized catalysts, the smallest crystallite size was observed with a 1:1 ratio of Ni ions to EDTA. However, an increase in the amount of EDTA resulted in excessive fuel supply, leading to an increase in crystallite size. Microstructure analysis revealed porous NiO agglomerates due to the use of EDTA, and differences in particle growth based on the fuel ratio were observed. We analyzed the growth behavior of CNTs grown using NiO nanocatalysts through catalytic chemical vapor deposition (CCVD). As the F/O ratio increased, it was observed that the catalyst particles grew excessively beyond hundreds of nanometers, preventing further CNT growth and leading to a rapid termination of CNT growth. Raman spectroscopy was used to analyze the structural characteristics of CNTs, and it was found that the ID/IG ratio indicated the highest CNT crystallinity near an F/O ratio of 1:1.

19.
Biosens Bioelectron ; 242: 115694, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37797531

ABSTRACT

Circulating tumor DNA (ctDNA) analysis has emerged as a highly promising non-invasive assay for detection and monitoring of cancer. However, identification of multiple point-mutant ctDNAs, particularly at extremely low frequencies in early cancer stages, remains a significant challenge. To address this issue, we present a multiplexed ctDNA detection technique, SIMUL (single-molecule detection of multiple low-frequency mutations). SIMUL involves an unbiased preamplification of both wild-type and mutant DNAs, followed by the detection of mutant DNAs through single-molecule multicolor imaging. SIMUL enables highly sensitive and specific detection of multiple single-nucleotide mutations in a short span of time, even in the presence of 10,000-fold excess of wild-type DNA. Importantly, SIMUL can accurately measure mutant fractions due to its linear correlation between the number of single-molecule spots and the variant allele frequency. This breakthrough technique holds immense potential for clinical applications, offering significant improvements for example in early cancer detection and accurate evaluation of anticancer treatment responses.


Subject(s)
Biosensing Techniques , Circulating Tumor DNA , Neoplasms , Humans , Circulating Tumor DNA/genetics , Neoplasms/diagnosis , Neoplasms/genetics , Mutation , Biomarkers, Tumor/genetics
20.
Sci Adv ; 9(34): eadh9962, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37624899

ABSTRACT

Developing soft robots that can control their own life cycle and degrade on-demand while maintaining hyperelasticity is a notable research challenge. On-demand degradable soft robots, which conserve their original functionality during operation and rapidly degrade under specific external stimulation, present the opportunity to self-direct the disappearance of temporary robots. This study proposes soft robots and materials that exhibit excellent mechanical stretchability and can degrade under ultraviolet light by mixing a fluoride-generating diphenyliodonium hexafluorophosphate with a silicone resin. Spectroscopic analysis revealed the mechanism of Si─O─Si backbone cleavage using fluoride ion (F-) and thermal analysis indicated accelerated decomposition at elevated temperatures. In addition, we demonstrated a robotics application by fabricating electronics integrated gaiting robot and a fully closed-loop trigger disintegration robot for autonomous, application-oriented functionalities. This study provides a simple yet novel strategy for designing life cycle mimicking soft robotics that can be applied to reduce soft robotics waste, explore hazardous areas, and ensure hardware security with on-demand destructive material platforms.

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