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1.
Appl Opt ; 60(30): 9425-9431, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34807082

RESUMO

A novel, to the best of our knowledge, thickness measurement scheme based on a phase shifting spectrally resolved interferometry is proposed for a thin film measurement from spectral reflectance and phase in a single sequence. This purpose is realized by introducing a spectral reflectance phase surface (SRPS). The spectral phase, originally existing in the form of an imaginary term, is revealed as a real term with the spectral reflectance due to the proposition of SRPS. Therefore, the reflectance and phase are contained in a single parameter, SRPS, and are measured in a single sequence. The phase shift error compensation is presented to form the accurate SRPS and ensure the performance of the measurement. The thickness of the sample is determined as the measured SRPS, and the theoretical SRPSs are compared by the cross correlation method. The performance of the proposed system is validated by measuring several samples of the SiO2 on a silicon substrate and comparing the results with the commercial ellipsometer.

2.
J Pers Med ; 11(11)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34834574

RESUMO

Postoperative gastrointestinal bleeding (PGIB) is a serious complication with expensive medical costs and a high mortality rate. This study aims to analyze the incidence of PGIB and its associated factors, including its relationship with postoperative analgesic use. Patients aged ≥20 years who received various kinds of surgery from 2013 to 2017 were included (n = 1,319,807). PGIB was defined by admission with ICD-10 codes of gastrointestinal bleeding plus transfusion within 2 months after surgery. A total of 3505 (0.27%) subjects had PGIB, and the incidence was much higher for those who underwent major gastrointestinal and major cardiovascular surgery (1.9% for both), followed by major head and neck (0.7%), major genitourinary (0.5%), and orthopedic surgery (0.45%). On multivariate analysis, older age, male sex, lower income, comorbidities, peptic ulcer disease, and congestive heart failure were associated with a higher risk of gastrointestinal bleeding. Among analgesics, steroid use was associated with increased postoperative bleeding risk (adjusted OR: 1.36, 95% CI: 1.25-1.48). Acetaminophen/nonsteroidal anti-inflammatory drugs, cyclooxygenase 2 inhibitors, anticonvulsants, antidepressants, and opioids were not associated with increased risk. PGIB is considerable for major surgeries, and its risk should be considered, especially for patients with older age and comorbidities and use of steroids.

3.
Appl Opt ; 60(29): 9231, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34624009

RESUMO

This publisher's note contains corrections to Appl. Opt.60, 8915 (2021).APOPAI0003-693510.1364/AO.435321.

4.
JACS Au ; 1(9): 1399-1411, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34604850

RESUMO

Gluing dynamic, wet biological tissue is important in injury treatment yet difficult to achieve. Polymeric adhesives are inconvenient to handle due to rapid cross-linking and can raise biocompatibility concerns. Inorganic nanoparticles adhere weakly to wet surfaces. Herein, an aqueous suspension of guanidinium-functionalized chitin nanoparticles as a biomedical adhesive with biocompatible, hemostatic, and antibacterial properties is developed. It glues porcine skin up to 3000-fold more strongly (30 kPa) than inorganic nanoparticles at the same concentration and adheres at neutral pH, which is unachievable with mussel-inspired adhesives alone. The glue exhibits an instant adhesion (2 min) to fully wet surfaces, and the glued assembly endures one-week underwater immersion. The suspension is lowly viscous and stable, hence sprayable and convenient to store. A nanomechanic study reveals that guanidinium moieties are chaotropic, creating strong, multifaceted noncovalent bonds with proteins: salt bridges comprising ionic attraction and bidentate hydrogen bonding with acidic moieties, cation-π interactions with aromatic moieties, and hydrophobic interactions. The adhesion mechanism provides a blueprint for advanced tissue adhesives.

5.
Appl Opt ; 60(28): 8915-8921, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613120

RESUMO

We proposed a new scheme of spectroscopic reflectometry (SR) that improves the stability with respect to the intensity variations of the incident light and simplifies the measurement procedure. The proposed method enables this by simultaneously measuring the incident light and the reflected light. Using the multi-order retarder, we modulate the incident light intensity into a high-frequency signal at the spectral domain. Even though the spectrometer measures the sum of reflected light and modulated incident light, each signal can be separately obtained using the Fourier transform. The proposed method is verified through the measurement of SiO2 thin film on the Si substrate with various incident light intensities.

6.
Microsyst Nanoeng ; 7: 59, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567771

RESUMO

MEMS inductors are used in a wide range of applications in micro- and nanotechnology, including RF MEMS, sensors, power electronics, and Bio-MEMS. Fabrication technologies set the boundary conditions for inductor design and their electrical and mechanical performance. This review provides a comprehensive overview of state-of-the-art MEMS technologies for inductor fabrication, presents recent advances in 3D additive fabrication technologies, and discusses the challenges and opportunities of MEMS inductors for two emerging applications, namely, integrated power electronics and neurotechnologies. Among the four top-down MEMS fabrication approaches, 3D surface micromachining and through-substrate-via (TSV) fabrication technology have been intensively studied to fabricate 3D inductors such as solenoid and toroid in-substrate TSV inductors. While 3D inductors are preferred for their high-quality factor, high power density, and low parasitic capacitance, in-substrate TSV inductors offer an additional unique advantage for 3D system integration and efficient thermal dissipation. These features make in-substrate TSV inductors promising to achieve the ultimate goal of monolithically integrated power converters. From another perspective, 3D bottom-up additive techniques such as ice lithography have great potential for fabricating inductors with geometries and specifications that are very challenging to achieve with established MEMS technologies. Finally, we discuss inspiring and emerging research opportunities for MEMS inductors.

7.
Sensors (Basel) ; 21(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34577383

RESUMO

Ammonia gas sensors were fabricated via layer-by-layer (LbL) deposition of diazo resin (DAR) and a binary mixture of tetrakis(4-sulfophenyl)porphine (TSPP) and poly(styrene sulfonate) (PSS) onto the core of a multimode U-bent optical fiber. The penetration of light transferred into the evanescent field was enhanced by stripping the polymer cladding and coating the fiber core. The electrostatic interaction between the diazonium ion in DAR and the sulfonate residues in TSPP and PSS was converted into covalent bonds using UV irradiation. The photoreaction between the layers was confirmed by UV-vis and Fourier transform infrared spectroscopy. The sensitivity of the optical fiber sensors to ammonia was linear when exposed to ammonia gases generated from aqueous ammonia solutions at a concentration of approximately 17 parts per million (ppm). This linearity extended up to 50 ppm when the exposure time (30 s) was shortened. The response and recovery times were reduced to 30 s with a 5-cycle DAR/TSPP+PSS (as a mixture of 1 mM TSPP and 0.025 wt% PSS in water) film sensor. The limit of detection (LOD) of the optimized sensor was estimated to be 0.31 ppm for ammonia in solution, corresponding to approximately 0.03 ppm of ammonia gas. It is hypothesized that the presence of the hydrophobic moiety of PSS in the matrix suppressed the effects of humidity on the sensor response. The sensor response was stable and reproducible over seven days. The PSS-containing U-bent fiber sensor also showed superior sensitivity to ammonia when examined alongside amine and non-amine analytes.


Assuntos
Amônia , Porfirinas , Umidade , Fibras Ópticas , Poliestirenos
8.
Nat Commun ; 12(1): 5211, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471118

RESUMO

Quantum metrology can achieve enhanced sensitivity for estimating unknown parameters beyond the standard quantum limit. Recently, multiple-phase estimation exploiting quantum resources has attracted intensive interest for its applications in quantum imaging and sensor networks. For multiple-phase estimation, the amount of enhanced sensitivity is dependent on quantum probe states, and multi-mode N00N states are known to be a key resource for this. However, its experimental demonstration has been missing so far since generating such states is highly challenging. Here, we report generation of multi-mode N00N states and experimental demonstration of quantum enhanced multiple-phase estimation using the multi-mode N00N states. In particular, we show that the quantum Cramer-Rao bound can be saturated using our two-photon four-mode N00N state and measurement scheme using a 4 × 4 multi-mode beam splitter. Our multiple-phase estimation strategy provides a faithful platform to investigate multiple parameter estimation scenarios.

9.
Vaccines (Basel) ; 9(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34358141

RESUMO

Following the clinical success of cancer immunotherapies such as immune checkpoint inhibitors blocking B7/CTLA-4 or PD-1/PD-L1 signaling and ongoing numerous combination therapies in the clinic,3 bispecific antibodies (BsAbs) are now emerging as a growing class of immunotherapies with the potential to improve clinical efficacy and safety further. Here, we describe four classes of BsAbs: (a) immune effector cell redirectors; (b) tumor-targeted immunomodulators; (c) dual immunomodulators; and (d) dual tumor-targeting BsAbs. This review describes each of these classes of BsAbs and presents examples of BsAbs in development. We reviewed the biological rationales and characteristics of BsAbs and summarized the current status and limitations of clinical development of BsAbs and strategies to overcome limitations. The field of BsAb-based cancer immunotherapy is growing, and more data from clinical trials are accumulating. Thus, BsAbs could be the next generation of new treatment options for cancer patients.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34360199

RESUMO

The coronavirus disease (COVID-19) pandemic is a global health threat and has posed a challenge for society and social care services as well as healthcare systems. Due to the risks involved in being exposed to the virus, public health actions such as wearing masks and physical distancing are necessary to reduce its spread. However, using non-validated masks is a serious issue as such masks may provide inadequate protection against airborne bioaerosol transmission, resulting in the spread of the virus. Therefore, it is necessary to evaluate the filtering performances of the masks against bioaerosols as well as particulate matter (PM). Here, we evaluated the filtering performances of sixteen different masks (four brands each of woven, antidroplet, KF80, and KF94 masks) commercially available in Korea with high market shares. As a simulation of being exposed to bioaerosols and to the yellow dust commonly found in Korea, the filtration efficiency levels of the masks were tested against airborne bacteria-containing droplets and against fine dusts of different ranges of particle sizes. Their filtration efficiency levels against the droplets showed strong positive correlations, specifically Pearson correlation coefficient r values of 0.917, 0.905, and 0.894, with their efficiency levels against PM1.0, PM2.5, and PM10, respectively. The results of this study should be useful for choosing appropriate masks, including those that meet filtering performance requirements.


Assuntos
COVID-19 , Bactérias , Filtração , Humanos , Tamanho da Partícula , República da Coreia , SARS-CoV-2
11.
Chemosphere ; 285: 131406, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34246097

RESUMO

Screening of polymeric microplastic debris can help to assess the extent to which plastics contaminate the environment. We here developed an easy- and rapid-to-perform method for the screening of plastic polymers, based on a newly employed fluorophore, namely 1-pyrenebutyric acid N-hydroxysuccinimidyl ester (PBN). The PBN fluorophore was capable of staining diverse synthetic microplastic polymers within 5 min, including those displaying various particle sizes and shapes. The fluorescence intensities of the microplastics were considerably enhanced after the short-duration staining. The screening method was shown to be highly effective in the detection of polyethylene (PE), poly(ethylene terephthalate) (PET), polyvinyl chloride (PVC), polyamide-6 (PA-6), polypropylene (PP), polystyrene (PS), polycarbonate (PC), polyvinylidenechloride (PVDC), and polyurethane (PU), with a lowest analyzed particle size of 15 µm. Using our screening method, plastic contamination was investigated in commercially available bottled waters and environmental waters, specifically urban freshwaters. This study demonstrated high affinity levels of the newly proposed PBN fluorophore for a broad range of polymers and its ability to be used to discernibly identify polymer particles.


Assuntos
Água Potável , Poluentes Químicos da Água , Água Potável/análise , Monitoramento Ambiental , Água Doce , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
12.
J Clin Med ; 10(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068652

RESUMO

BACKGROUND: We aimed to investigate molecular factors potentially related to the progression of gastric adenoma (GA) to gastric cancer (GC) and compare the mutation characteristics between GC and GA. METHODS: We conducted custom gene panel sequencing for 135 GC-related genes and estimated the difference in somatic mutation profiles between 20 GC and 20 GA cases. RESULTS: A total of 31 somatic mutations, including 22 missense, 3 nonsense, and 6 frameshift mutations, were detected in 17 samples. We estimated an average of 1.8 mutations per sample (range, 1 to 3 mutations), with 12 in GC and 5 in GA. GC tended to have one or more mutated genes (p = 0.0217), as well as higher allele frequencies of mutated genes (p = 0.0003), compared to GA. Likewise, known driver mutations associated with GC tumorigenesis (TP53, ERBB2, PIK3CA, and RNF43) were identified in half of the GC cases (50%, 10/20; p = 0.0002). Only the mutant burden, regardless of gene type, was retained, with an odds ratio of 1.8392 (95% confidence interval (CI), 1.0071 to 3.3588; p = 0.0474). CONCLUSION: Our study demonstrates that the accumulation of mutant burden contributes to tumorigenesis progression from GA to GC in Korean patients, regardless of the kind of genes. These findings may elucidate the molecular pathogenesis of gastric carcinogenesis and malignant progression.

13.
Cancer Res Treat ; 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33940785

RESUMO

Purpose: There remains controversy about relationship between obesity and gastric cancer. We aimed to examine the association using obesity-persistence. Materials and Methods: We analyzed a nationwide population-based cohort which underwent health check-up between 2009 and 2012. Among them those who had annual examinations during the last 5 years were selected. Gastric cancer risk was compared between those without obesity during the five years (never-obesity group) and those with obesity diagnosis during the five years (non-persistent obesity group; persistent obesity group). Results: Among 2,757,017 individuals, 13,441 developed gastric cancer after median 6.78 years of follow-up. Gastric cancer risk was the highest in persistent obesity group (incidence rate (IR), 0.89/1,000 person-years; hazard ratio (HR), 1.197; 95% confidence interval (CI), 1.117-1.284), followed by non-persistent obesity group (IR, 0.83/1,000 person-years; HR, 1.113; 95% CI, 1.056-1.172) compared with never-obesity group. In subgroup analysis, this positive relationship was true among those <65 years old and male. Among heavy-drinkers, the impact of obesity-persistence on the gastric cancer risk far increased (non-persistent obesity: HR 1.297, 95% CI 1.094-1.538; persistent obesity: HR 1.351, 95% CI 1.076-1.698). Conclusion: Obesity-persistence is associated with increased risk of gastric cancer in a dose-response manner, especially among male <65 years old. The risk raising effect was much stronger among heavy-drinkers.

15.
J Clin Med ; 10(7)2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33916604

RESUMO

We investigated whether longitudinal patterns in antithrombotic therapy have changed after the introduction of non-vitamin K oral anticoagulants (NOACs) in patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI). Using a claims database of the Korean AF population who underwent PCI between 2012 and 2016 (n = 18,691), we analyzed prescription records of oral anticoagulants (OACs) and antiplatelets at 3-month intervals over 2 years after PCI. The study population was stratified (pre-NOAC, transition, and NOAC era) using time-periods of NOAC introduction in Korea and an expansion of reimbursement for NOAC in AF as indicators. The overall rates of OAC were low at baseline (24.9%, 26.9%, and 35.2% in pre-NOAC, transition, and NOAC era, respectively), contrary to high rates of dual antiplatelet therapy (DAPT) (73.3%, 71.4%, and 63.6%). However, OAC prescription rates were increased at 1-year (18.5%, 22.5%, and 31.6%), and 2-year follow-up (17.8%, 24.2%, and 31.8%) from pre-NOAC to NOAC era. In NOAC era, 63.5% of baseline OAC prescriptions comprised NOAC, of which 96.4% included triple therapy with DAPT. Over 2 years, we observed increasing rates of double therapy with a single antiplatelet (18.3% and 20.0% at 1- and 2-year follow-up) and OAC monotherapy (2.7% and 8.9% at 1- and 2-year follow-up).

16.
Cereb Cortex ; 31(8): 3678-3700, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33749727

RESUMO

Despite ongoing advances in our understanding of local single-cellular and network-level activity of neuronal populations in the human brain, extraordinarily little is known about their "intermediate" microscale local circuit dynamics. Here, we utilized ultra-high-density microelectrode arrays and a rare opportunity to perform intracranial recordings across multiple cortical areas in human participants to discover three distinct classes of cortical activity that are not locked to ongoing natural brain rhythmic activity. The first included fast waveforms similar to extracellular single-unit activity. The other two types were discrete events with slower waveform dynamics and were found preferentially in upper cortical layers. These second and third types were also observed in rodents, nonhuman primates, and semi-chronic recordings from humans via laminar and Utah array microelectrodes. The rates of all three events were selectively modulated by auditory and electrical stimuli, pharmacological manipulation, and cold saline application and had small causal co-occurrences. These results suggest that the proper combination of high-resolution microelectrodes and analytic techniques can capture neuronal dynamics that lay between somatic action potentials and aggregate population activity. Understanding intermediate microscale dynamics in relation to single-cell and network dynamics may reveal important details about activity in the full cortical circuit.

17.
Small ; 17(19): e2007579, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33734574

RESUMO

Electrical conductivity, mechanical flexibility, and large electroactive surface areas are the most important factors in determining the performance of various flexible electrodes in energy storage devices. Herein, a layer-by-layer (LbL) assembly-induced metal electrodeposition approach is introduced to prepare a variety of highly porous 3D-current collectors with high flexibility, metallic conductivity, and large surface area. In this study, a few metal nanoparticle (NP) layers are LbL-assembled onto insulating paper for the preparation of conductive paper. Subsequent Ni electroplating of the metal NP-coated substrates reduces the sheet resistance from ≈103 to <0.1 Ω sq-1 while maintaining the porous structure of the pristine paper. Particularly, this approach is completely compatible with commercial electroplating processes, and thus can be directly extended to electroplating applications using a variety of other metals in addition to Ni. After depositing high-energy MnO NPs onto Ni-electroplated papers, the areal capacitance increases from 68 to 811 mF cm-2 as the mass loading of MnO NPs increases from 0.16 to 4.31 mg cm-2 . When metal NPs are periodically LbL-assembled with the MnO NPs, the areal capacitance increases to 1710 mF cm-2 .

18.
Immune Netw ; 21(1): e1, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33728094

RESUMO

The emergence of a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a significant health concern worldwide. Undoubtedly, a better understanding of the innate and adaptive immune responses against SARS-CoV-2 and its relationship with the coronavirus disease 2019 (COVID-19) pathogenesis will be the sole basis for developing and applying therapeutics. This review will summarize the published results that relate to innate immune responses against infections with human coronaviruses including SARS-CoV-1 and SARS-CoV-2 in both humans and animal models. The topics encompass the innate immune sensing of the virus to the dysregulation of various innate immune cells during infection and disease progression.

19.
J Nanosci Nanotechnol ; 21(8): 4537-4543, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33714358

RESUMO

This study examined the effects of the porosity of catalytic bag-filter materials for applications to the SNCR (selective noncatalytic reduction)-SCR (selective catalytic reduction) hybrid process for highly treating nitrogen Oxides (NOx) in the exhaust gas of a combustion process. A V2O5/TiO2 catalyst was dispersed in a PTFE (poly-tetra-fluoro-ethylene) used as the catalytic bag-filter material to remove particulate matter and nitrogen oxides contained in the combustion exhaust gas. Macroporous alumina was added into a V2O5/TiO2-dispersed PTFE to improve the catalytic activity of V2O5/TiO2 dispersed in the PTFE material. In this study, the textural properties and denitrification performances of the V2O5/TiO2-dispersed PTFE materials were examined according to the addition of macro-porous alumina. When the denitrification catalyst was solely dispersed in the PTFE material, the catalyst inside the PTFE backbone had low gas-solid contact efficiency owing to the low porosity of the PTFE materials, resulting in low denitrification efficiency. On the other hand, the catalytic activity of V2O5/TiO2 dispersed inside the macro-porous PTFE material was significantly enhanced by adding macro-porous alumina into the PTFE matrix. The enhanced textural properties of the macro-porous PTFE material where V2O5/TiO2 was uniformly dispersed proved the facilitated diffusion of combustion exhaust gas into the PTFE material.

20.
Korean Circ J ; 51(5): 409-422, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33764010

RESUMO

BACKGROUND AND OBJECTIVES: Antithrombotic therapy after percutaneous coronary intervention (PCI) in patients with atrial fibrillation (AF) has changed in recent years with new data from large randomized trials and updates to clinical guidelines. This study aimed to investigate the trends in periprocedural antithrombotic regimens in Korean patients with AF undergoing PCI with non-vitamin K antagonist oral anticoagulants (NOACs). METHODS: Using the claims database of the Health Insurance Review and Assessment during 2013-2018, 27,594 patients with AF undergoing PCI were identified. The annual prevalence of PCI and prescriptions of each antithrombotic agent, including antiplatelet agents and oral anticoagulants, within 30 days after PCI were investigated. RESULTS: During 2013-2018, the number of patients with AF undergoing PCI increased up to 1.3-fold (from 3,913 to 5,075 patients per year). After the introduction of NOACs, the proportion of dual antiplatelet therapy (DAPT) decreased from 71.9% to 49.8% but still occupied the largest proportion among antithrombotic regimens. Triple antithrombotic therapy (TAT) use increased from 25.4% to 46.0%, and NOAC has rapidly replaced warfarin as the oral anticoagulant of choice. TAT was preferred to DAPT for patients with CHA2DS2-VASc score ≥2. Among various factors, prior intracranial hemorrhage was the most powerful predictor of favoring DAPT use over TAT. CONCLUSION: Since the introduction of NOACs, the patterns of periprocedural antithrombotic regimens have changed rapidly toward more use of TAT, specifically with NOAC-based regimen. Appropriate stroke prevention with oral anticoagulants is still underutilized in patients with AF undergoing PCI in Korea.

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