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Infectious bacteria evolve fast into resistance to conventional antimicrobial agents, whereas treatments for drug resistance bacteria progress more slowly. Here, we report a universally applicable photoactivated antimicrobial modality through light-responsive carbon dot-embedding soft hyaluronic acid hydrogel (CDgel). Because of the innate nature of the infectious bacteria that produce hyaluronidase, applied hyaluronic acid-based CDgel breaks down via bacteria and releases carbon dots (CDs) into the infectious sites. The released CDs possess photodynamic capabilities under light irradiation, inducing

PurposeSocial media have increasingly gained credibility as information sources in emergencies. Retweeting or resharing nature has made Twitter a popular medium of information dissemination. The purpose of this article is to enhance our understanding of both linguistic style and content properties (i.e. both affective and informational contents) that drives resharing behavior or virality of disaster messages on Twitter. We investigate this issue in the context of natural disaster crisis.Design/methodology/approachIn this study, the authors develop, drawing upon language expectancy and uncertainty reduction theories as an enabling framework, hypotheses about how the language (i.e. style and content) influence resharing behavior. They employ a natural language processing of disaster tweets to examine how the language – linguistic style (concrete and interactive language) and linguistic content (information- and affect-focused language) – affects resharing behavior on Twitter during natural disasters. To examine the effects of both linguistic style and content factors on virality, a series of negative binomial regressions were conducted, particularly owing to the highly skewed count data.FindingsOur analysis of tweets from the 2013 Colorado floods shows that resharing disasters tweets increases with the use of concrete language style during acute emergencies. Interactive language is also positively associated with retweet frequency. In addition, neither positive nor negative emotional tweets drive down resharing during acute crises, while information-focused language content has a significantly positive effect on virality.Practical implicationsAgencies for public safety and disaster management or volunteer organizations involved in disseminating crisis and risk information to the public may leverage the impacts of the linguistic style and language content through the lens of our research model. The findings encourage practitioners to focus on the role of linguistic style cues during acute disasters. Specifically, from the uncertainty reduction perspective, using concrete language in the disaster tweets is the expected norm, leading to a higher likelihood of virality. Also, interactively frame disaster tweets are more likely to be diffused to a larger number of people on Twitter.Originality/valueThe language that people use offer important psychological cue to their intentions and motivations. However, the role of language on Twitter has largely been ignored in this crisis communication and few prior studies have examined the relationship between language and virality during acute emergencies. This article explains the complex and multifaceted nature of information resharing behavior using a multi-theoretical approach – including uncertainty reduction and language expectancy theory – to understand effects of language style and content cues on resharing behavior in the context of natural crisis events.

As a novel approach to the in situ real-time investigation of an ITO electrode during the wet etching process, step-excitation Fourier-transform electrochemical impedance spectroscopy (FT-EIS) was implemented. The equivalent circuit parameters (e.g., Rct, Cdl) continuously obtained by the FT-EIS measurements during the entire etching process showed an electrode activation at the initial period as well as the completion of etching. The FT-EIS results were further validated by cyclic voltammograms and impedance measurements of partially etched ITO films using ferri- and ferrocyanide solution in combination with FESEM imaging, EDS, XRD analyses, and COMSOL simulation. We also demonstrated that this technique can be further utilized to obtain intact interdigitated array (IDA) electrodes in a reproducible manner, which is generally considered to be quite tricky due to delicacy of the pattern. Given that the FT-EIS allows for instantaneous snapshots of the electrode at every moment, this work may hold promise for in situ real-time examination of structural, electrokinetic, or mass transfer-related information on electrochemical systems undergoing constantly changing, transient processes including etching, which would be impossible with conventional electroanalytical techniques.

Lifetime imaging methods using phosphorescence quenching by oxygen for molecular oxygen concentration measurement have been developed and used for non-invasive oxygen monitoring. This study reports photoacoustic (PA) oxygen imaging powered by polyacrylamide (PAAm) hydrogel nanoparticle (NP) which offer advantages including improved biocompatibility, reduced toxicity, and active tumor targeting. A known oxygen indicator, oxyphor G2, was conjugated with the matrix of the NPs, giving G2-PAA NPs, followed by PEGylation for biocompatibility and F3 surface modification for tumor targeting. Using two lasers providing pump and probe pulses, respectively, PA imaging was performed so as to quantitatively map the oxygen concentration in biological tissues in vivo, including cancer tumors and normal thigh muscles. Furthermore, via the imaging at the pump wavelength and two additional wavelengths, the accumulation of the G2-PAA NPs in the tumors were also determined. The successful imaging experiment accomplished on animal models renders a method for in vivo non-invasive imaging and assessment of hypoxic tumor microenvironments, which is critical for assessing cancer progression, metastasis, and treatment.

The recent outbreak of COVID-19 has highlighted the seriousness of airborne diseases and the need for a proper pathogen detection system. Compared to the ample amount of research on biological detection, work on integrated devices for air monitoring is rare. In this work, we integrated a wet-cyclone air sampler and a DC impedance microfluidic cytometer to build a cyclone-cytometer integrated air monitor (CCAM). The wet-cyclone air sampler sucks the air and concentrates the bioaerosols into 10 mL of aqueous solvent. After 5 min of air sampling, the bioaerosol-containing solution was conveyed to the microfluidic cytometer for detection. The device was tested with aerosolized microbeads, dust, and Escherichia coli (E. coli). CCAM is shown to differentiate particles from 0.96 to 2.95 μm with high accuracy. The wet cyclone air-sampler showed a 28.04% sampling efficiency, and the DC impedance cytometer showed 87.68% detection efficiency, giving a total of 24.59% overall CCAM efficiency. After validation of the device performance, CCAM was used to detect bacterial aerosols and their viability without any separate pretreatment step. Differentiation of dust, live E. coli, and dead E. coli was successfully performed by the addition of BacLight bacterial viability reagent in the sampling solvent. The usage could be further extended to detection of specific species with proper antibody fluorescent label. A promising strategy for aerosol detection is proposed through the constructive integration of a DC impedance microfluidic cytometer and a wet-cyclone air sampler.

Purpose Serial crowdfunding is becoming a common phenomenon as entrepreneurs repeatedly return to online crowdfunding to raise capital. In this study, the authors focus attention on serial crowdfunders, that is, entrepreneurs who experience launching more than one crowdfunding project. The purpose of this paper is to investigate the role of past experience on subsequent crowdfunding performance. This study also examines whether initial success vs initial failure leads serial crowdfunders to engage in more explorative behaviors (i.e. switching industry) and to take exploitative actions (i.e. adjusting campaign strategies in terms of goal setting and funding option). Design/methodology/approach Data on serial crowdfunding projects was retrieved from Indiegogo platform. The logistic regression models are estimated to assess the impact of past entrepreneurial experience on subsequent crowdfunding decisions, and to estimate the effects of the three strategies on subsequent funding performance. Findings The results show that serial creators who experienced successful initial crowdfunding are more likely to explore a new industry or product category in the crowdfunding market and to set a higher target capital for the subsequent campaign when they change a project category. Originality/value Despite the fact that there are a considerably large number of serial crowdfunders in crowdfunding market, relatively little research has been conducted to investigate the presence of learning benefits from a previous to a subsequent crowdfunding project. Two competing hypotheses, drawn from the attribution theory and hubris theory of entrepreneurship, were tested in this study to determine the impact of prior success vs failure experience on both subsequent crowdfunding decisions and funding performance.

As a robust radioanalytical method for tracking carbonaceous particulates in vivo, polycyclic aromatic hydrocarbons from diesel exhaust were labeled with a radioactive-iodine-tagged pyrene analogue. Single-photon emission computed tomography and biodistribution studies showed high uptake and slow clearance of this matter in the respiratory system, which may underlie its severe toxicity.

Extracellular deposition of β-amyloid (Aβ) peptide aggregates is a major characteristic of Alzheimer's disease (AD) brain. Because Aβ peptide aggregates aggravate neuropathy and cognitive impairment for AD patients, numerous efforts have been devoted to suppressing Aβ self-assembly as a prospective AD treatment option. Here, we report Aβ-targeting, red-light-responsive carbon dots (CDs), and their therapeutic functions as a light-powered nanomodulator to spatiotemporally suppress toxic Aβ aggregation both in vitro and in vivo. Our aptamer-functionalized carbon dots (Apta@CDs) showed strong targeting ability toward Aβ42 species. Moreover, red LED irradiation induced Apta@CDs to irreversibly denature Aβ peptides, impeding the formation of β-sheet-rich Aβ aggregates and attenuating Aβ-associated cytotoxicity. Consequently, Apta@CDs-mediated photomodualtion modality achieved effective suppression of Aβ aggregation in vivo, which significantly reduced the Aβ burden at the targeted sites in the brain of 5xFAD mice by ∼40% and ∼25% according to imaging and ELISA analyses, respectively. Our work demonstrates the therapeutic potential of photomodulating CDs for light-driven suppression against Aβ self-assembly and related neurotoxicity.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder and affects more than 10% of the population aged over 65 worldwide. Despite considerable global efforts, AD patients can only be diagnosed after the onset of symptoms based on neuropsychological tests and neuroimaging. Because the changes in the levels of biomarkers associated with Aβ deposits and tau tangles precede the appearance of the first cognitive symptoms, accurate measurements of AD core biomarkers is critical for identifying asymptomatic AD patients and predicting disease progression. In this regard, significant efforts have been made to develop novel AD biomarker-targeting sensor platforms that have superb sensitivity and high accessibility. This review provides an overview of recent advances in optical and electrical sensing of core AD biomarkers in clinically relevant fluids such as the cerebrospinal fluid and human blood. We have summarized current challenges and future strategies for translating the sensing techniques discovered in the academic laboratories into clinical analytic platforms for early diagnosis of AD.

Hearing loss is the most common human sensory deficit, affecting normal communication. Recently, patients with hearing loss or at risk of hearing loss are increasingly turning to the online health community for health information and support. Information on health-related topics exchanged on the Internet is a useful resource to examine patients’ informational needs. The ability to understand the patients’ perspectives on hearing loss is critical for health professionals to develop a patient-centered intervention. In this paper, we apply Latent Dirichlet Allocation (LDA) on electronic patient-authored questions on social question-and-answer (Q&A) sites to identify patients’ perceptions, concerns, and needs on hearing loss. Our results reveal 21 topics, which are both representative and meaningful, and mostly correspond to sub-fields established in hearing science research. The latent topics are classified into five themes, which include “sudden hearing loss”, “tinnitus”, “noise-induced hearing loss”, “hearing aids”, “dizziness”, “curiosity about hearing loss”, “otitis media” and “complications of disease”. Our topic analysis of patients’ questions on the topic of hearing loss allows achieving a thorough understanding of patients’ perspectives, thereby leading to better development of the patient-centered intervention.

This study examined the microstructures, crystal structures, and electrical properties of 0.01 mol CuO–added (1–x)(Bi1/2Na1/2)TiO3–xSrTiO3–2BiFeO3 (BNST100x–2BF, x = 0.20 ~ 0.28) ceramics synthesized at two different sintering temperatures. The sintering temperature of the BNST100x–2BF ceramics could be decreased from 1175 °C to 1000 °C by adding a 0.01 mol CuO excess. Low–temperature sintering led to a decrease in average grain size. The dielectrics, polarization hysteresis (P–E), switching current, and electric–field induced strain (S–E) curves changed with increasing SrTiO3 content and decreasing sintering temperature. Interestingly, the highest reduction ratio of d33* was calculated to be somewhere in between the high–temperature sintered and low–temperature sintered BNST26–2BF ceramics. These results were attributed to the difference in the stabilized relaxor state and closely related to the electric field–induced reversible phase transition from the relaxor and ferroelectrics.

In order to obtain the fundamental data about labor-saving and fishing efficiency of the anchovy scoop net fishery in the coastal area of Jeju island, the fishing system using the carrying apparatus, the depth controller and the modified anchovy scoop net was designed and carried out at fishing ground. As the results, the carrying apparatus as the labor-saving devices was suitable to transfer the fishing lamp to the target spot steady and exactly regardless of weather at fishing ground. In addition, when the depth controller instead of the pressing stick in traditional method was replaced, the entrance of the net was spreaded out adequately without man power. These invented fishing gears such as the carrying apparatus and the depth controller including the modified anchovy scoop net reduced operating persons by about 50% from 7-8 to 3-4 persons.

A lot of people in Korea have suffered from severe toxicity of PHMG, a humidifier disinfectant. To assess the risk and in-depth mechanistic understanding of toxicity posed by a hazardous substance, it is essential to determine its biological uptake in organs. In this study, we investigate the biodistribution of PHMG using radioanalytical techniques. By labeling PHMG with radioactive indium (111In), the uptake values of PHMG in organs can be measured after intravenous injection in Sprague–Dawley rats for up to 168 h. The results indicate that PHMG is distributed in the liver (28.63% injected dose (%ID)) and lungs (12.44%ID) at 30 min post administration. In addition, the clearance rate of PHMG distributed in the internal organs is slow, with approximately 65% of injected PHMG remaining in the lungs after 1 week. Moreover, we quantified biodistribution of the radiolabeled PHMG exposed through intratracheal instillation and oral administration routes, and the observed data were compared to each other to understand in vivo behavior of PHMG. In addition, radiolabeled PHMG in an animal model can be visualized using SPECT/CT. The obtained results indicate that repetitive exposure to PHMG results in damage to lungs, as well as extrapulmonary organs.

We herein present a suquential procedure for separation of nuclides such as 55Fe, 94Nb, 59,63Ni, 90Sr, and 99Tc from activated carbon and stainless steel samples orignating from low and intermediate level of radioactive waste. Initially, iron was removed through the precipitation of Fe(OH)3 upon the addition of NH4OH. The recoveries of Fe and Nb in the precipitate were 98.4 ± 2.9 and 98.5 ± 0.52%, respectively, while those of Ni, Re, and Sr in the supernatant were 74.0 ± 4.0, 96.7 ± 1.2, and 79.6 ± 1.2%, respectively. However, due to the especially low recovery of Re from the supernatant following anion exchange chromatography, the Fe precipitate was removed after the separation of Re by anion exchange chromatography. Our results indicate that this procedure is suitable for providing pure nuclides from waste samples to allow the measurement of their radioactive activities.

We investigated microstructures, crystal structures, and electrical properties of high temperature sintered (1‒x)BiNaTiO3‒xSrTiO3‒2BiFeO3 (BNST100x‒2BF, x = 0.20 and 0.22) ceramics without added CuO and compared these results with low temperature sintered BNST100x‒2BF ceramics with 1 mol% of added CuO. The sintering temperature and average grain size of BNST100x‒2BF ceramics decreased after addition of CuO. We found that changes in the stabilized relaxor phase with decreasing sintering temperature resulted in changes in the temperature dependent dielectric properties and provided the enhanced electromechanical strain properties in BNST100x‒2BF ceramics. Therefore, we suggest that the nonergodicity to ergodicity transition is able to induce by changes in sintering temperature with added CuO and this result is important to tailor the electrical properties of BNT‒based lead‒free ceramics in proceeding with practical application.

Owing to the geographic disadvantages of mountain villages, the social, cultural, and economic conditions of mountain villagers are inferior to those of urban dwellers in South Korea. Thus, in 1995, the The government of South Korea launched a mountain village development support program to promote agriculture and forestry, balance national land development, and preserve cultural heritage. The program was effectively implemented, improving the income, population size, and living conditions of villagers in addition to setting up a system for stable project implementation. However, concerns were raised about long-term development planning, the creation and marketing of specialty brands, facility management/operation, and follow-up support. The government conducted surveys of mountain villagers in 2003 and 2014, obtaining basic data to address these issues. This study evaluates the outcomes of these two surveys, suggesting areas requiring focused action, concentrating on village development projects, forest resource distribution and use, demographic trends, the economy, exchange with urban areas, green tourism, and master planning. We find that despite growth in the forest labor force, forest ownership is diminishing in terms of the number and scale of holdings. Consequently, it is necessary to commercialize forest resources, establish favorable settlement conditions, and expand government support for village-run projects. In addition, systematic forest management for older tree age classes would benefit the public and provide assets for future mountain village development. Our results are expected to provide baseline information for the establishment and efficient implementation of mountain village development policy.

The crystal structure, ferroelectric, and electric-field-induced strain (EFIS) properties of Bi-based lead-free ferroelectric/relaxor composite materials are investigated. Bi1/2(Na0.82K0.18)1/2TiO3 as a ferroelectric material and 0.98Bi1/2(Na0.78K0.22)1/2TiO3‒0.02LaFeO3 as a relaxor were synthesized via conventional ceramic processing routes while the relaxor (matrix phase) was prepared via high-energy ball milling (HEBM) after calcination. The average particle size was decreased via HEBM treatment. As a result, a high d33* value of over 600 pm/V was obtained at 4 kV/mm for 30-min HEBM-treated composites. This demonstrates that HEBM treatment is effective in enhancing the strain properties of lead‒free piezoelectric composite materials.

PurposeThe purpose of this paper is to explore how linguistic style and message substance influence persuasion in civic crowdfunding marketplaces in which written narrative pitch become a vital communication to attract private contributions to public goods and services. Drawing on the elaboration likelihood model (ELM), the authors operationalize the linguistic style of the narrative pitch as language power and message substance as issue-relevant argument quality. In this paper, the authors examine how characteristics of both style and message are related to the outcome of civic crowdfunded projects.Design/methodology/approachThe data on civic crowdfunding projects were retrieved from Spacehive, the platform that dedicated mainly to civic projects ranging from community programs, social-oriented enterprises, to infrastructure or facility development. Each of the narrative samples is analyzed using a computerized text analysis package called the Linguistic Inquiry and Word Count to extract the features of the linguistic style and message substance in the narratives. The logistic regression models are estimated to assess the impact of both linguistic style and message substance on crowdfunding decisions.FindingsThe results show that funding outcomes can be improved with psychological language dimensions (i.e. positive affective and perceptual language). However, extensive use of social language does not help project creators to increase their chance of funding performance; but instead, such language reduces the likelihood of project success. Additionally, message substance or issue-relevant information such as money and risk language influences funding outcome.Originality/valueVery few empirical studies investigated the differential effects of language style and message substance on funding performance of crowdfunding campaigns. The authors draw upon the dual process of persuasion as a theoretical base to identify a comprehensive set of linguistic style and message substance and to examine the role of such features in an emerging civic crowdfunding market. This study advances the application of the dual process in ELM by identifying and examining distinct persuasive cues originating from linguistics styles and message contents.

Retweeting or resharing nature has made Twitter a popular medium of information dissemination during disasters, yet few studies have investigated the effect of the language on resharing behavior during acute emergencies. In this study, we develop, drawing upon language expectancy and uncertainty reduction theories as an enabling framework, hypotheses about how the language (i.e., style and content) influence resharing behavior. We employ a natural language processing of disaster tweets to examine how the language – linguistic style (concrete and interactive language) and linguistic content (information- and affect-focused language) – affects resharing behavior on Twitter during natural disasters. Our analysis of tweets from the 2013 Colorado floods shows that resharing disasters tweets increases with the use of concrete language style during acute emergencies. Interactive language is also positively associated with retweet frequency. In addition, neither positive nor negative emotional tweets have a significant effect on resharing during acute crises, while information-focused language content has a significantly positive effect on virality.

In this report, we present a rapid and highly efficient method for radioactive iodine labeling of trans -cyclooctene group conjugated biomolecules using inverse-electron-demand Diels–Alder reaction. Radioiodination reaction of the tetrazine structure was carried out using the stannylated precursor 2 to give 125 I-labeled product ([ 125 I] 1 ) with high radiochemical yield (65 ± 8%) and radiochemical purity (>99%). For radiolabeling application of [ 125 I] 1 , trans -cyclooctene derived cRGD peptide and human serum albumin were prepared. These substrates were reacted with [ 125 I] 1 under mild condition to provide the radiolabeled products [ 125 I] 6 and [ 125 I] 8 , respectively, with excellent radiochemical yields. The biodistribution study of [ 125 I] 8 in normal ICR mice showed significantly lower thyroid uptake values than that of 125 I-labeled human serum albumin prepared by a traditional radiolabeling method. Therefore [ 125 I] 8 will be a useful radiolabeled tracer in various molecular imaging and biological studies. Those results clearly demonstrate that [ 125 I] 1 will be used as a valuable prosthetic group for radiolabeling of biomolecules.