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Objective:The objective of this study is to evaluate the safety and efficacy of a tumor-specific apoptosis-inducing gene, apoptin, as delivered by the non-viral carrier, PAM-RG4, in an animal model of spinal cord tumor.Methods:Male Sprague-Dawley rats were given a 2.5-μl intramedullary injection of C6 glioma (100 000) cells and randomized into three groups (day 0). On day 5, animals received a 7.5-μl intramedullary injection of Dulbecco's modified Eagle's medium (Group 1; n=7), PAM-RG4/control gene polyplex (Group 2; n=7), or PAM-RG4/apoptin gene polyplex (Group 3; n=8). Hindlimb functional strength was assessed every other day for the duration of the study. The spinal cords of killed animals were collected and hematoxylin-eosin stained.Results:Following treatment, animals that received apoptin had significantly higher mean functional hindlimb scores than those of sham control animals, showing a level of preserved hindlimb function throughout the study. In addition, Group 1 (sham control) and Group 2 (control gene) animals had median survival scores lower than those of animals receiving apoptin. Histopathological analysis showed marked retardation of tumor progression in apoptin-treated animals compared with sham controls.Conclusion:Our study suggests that apoptin is safe for use in the mammalian spinal cord as well as effective in slowing the progression of tumor growth in the spinal cord. The significant slowing of tumor progression, as manifested by the preserved hindlimb function, coupled with the reduction in tumor volume, shows local non-viral delivery of apoptin could serve as an emerging therapy for the treatment of intramedullary spinal cord tumors. [ABSTRACT FROM AUTHOR]

This study examines the usability of communication-assistive applications for hearing-impaired users, with a focus on enhancing user experience and promoting social inclusion. Although such applications have been developed and evaluated previously, interface designs that consider the intimacy needs of hearing-impaired users remain under-explored. We performed a comprehensive usability evaluation employing a mixed-method approach, which involved hearing-impaired individuals as well as field experts. The findings revealed areas for improvement in the design, validated the feasibility of implementing these applications, and emphasized the importance of incorporating the unique needs and preferences of hearing-impaired users. Furthermore, this paper discusses the importance of introducing guidelines and evaluation scales for the "Design for Emotion and Life Knowledge" levels to facilitate smooth and effective human-computer interactions. Such measures will promote the development of intelligent assistive technologies that reflect the qualitative needs of people with disabilities and contribute to social rights for hearing-impaired users. With the growing demands of artificial-intelligence-powered assistive technologies, the inclusion of individuals with disabilities in the design and research process is anticipated to increase. In future, studies should be conducted to blend the culturally shared experiences and emotional bonds expressed by users (having mild-to-severe hearing impairment) with the design and development process of assistive devices or services., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kim et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

15 N-Labeled azides are important probes for infrared and magnetic resonance spectroscopy and imaging. They can be synthesized by reaction of primary amines with a 15 N-labeled diazo-transfer reagent. We present the synthesis of 15 N-labeled 2-azido-1,3-dimethylimidazolinium salts 1 as a 15 N-labeled diazo-transfer reagent. Nitrosation of 1,3-dimethylimidazolinium-2-yl hydrazine ( 2 ) with Na 15 NO 2 under acidic conditions gave 1 as a 1:1 mixture of α- and γ- 15 N-labeled azides, α- and γ- 1 , rather than γ- 1 alone. The isotopomeric mixture thus obtained was then subjected to the diazo-transfer reaction with primary amines 3 to afford azides 4 as a 1:1 mixture of β- 15 N-labeled azides β- 4 and unlabeled ones 4' . The efficient and inexpensive synthesis of 1 as a 1:1 mixture of α- and γ- 1 using Na 15 NO 2 instead of Na 15 NNN facilitates their wide use as a 15 N-labeled diazo-transfer reagent for preparing 15 N-labeled azides as molecular probes., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Facial expression recognition technology has been utilized both for entertainment purposes and as a valuable aid in rehabilitation and facial exercise assistance. This technology leverages artificial intelligence models to predict facial landmark points and provide visual feedback, thereby facilitating users' facial movements. However, feedback designs that disregard user preferences may cause discomfort and diminish the benefits of exercise. This study aimed to develop a feedback design guide for facial rehabilitation exercises by investigating user responses to various feedback design methods. We created a facial recognition mobile application and designed six feedback variations based on shape and transparency. To evaluate user experience, we conducted a usability test involving 48 participants (24 subjects in their 20s and 24 over 60 years of age), assessing factors such as feedback, assistance, disturbance, aesthetics, cognitive ease, and appropriateness. The experimental results revealed significant differences in transparency, age, and the interaction between transparency and age. Consequently, it is essential to consider both transparency and user age when designing facial recognition feedback. The findings of this study could potentially inform the design of more effective and personalized visual feedback for facial motion, ultimately benefiting users in rehabilitation and exercise contexts.

We study a systematic formation of continuous exceptional points (EPs) in a fully-asymmetric optical microdisk. A parametric generation of chiral EP modes is investigated by analyzing asymmetricity-dependent coupling elements in an effective Hamiltonian. It is shown that given the external perturbation, the frequency splitting around EPs is scaled by the fundamental "strength" of EPs [J. Wiersig, Phys. Rev. Res.4, 023121 (2022)10.1103/PhysRevResearch.4.023121] multiplied by the extra responding strength of the newly added perturbation. Our finding demonstrates that the sensitivity of EP-based sensors can be maximized by carefully examining the continuous formation of EPs.

d-amino acid-based surfactants (d-AASs) were synthesized and their antimicrobial activity was evaluated. N -α-lauroyl-d-arginine ethyl ester hydrochloride (d-LAE), d-proline dodecyl ester (d-PD), and d-alanine dodecyl ester (d-AD) were found to have antibacterial activity against both Gram-positive and -negative bacteria, but less efficacy against Gram-negative bacteria. For these reasons, combining antimicrobial agents with nanoparticles is a promising technique for improving their antibacterial properties to eliminate drug-resistant pathogens. d-LAE coated on gold (AuNP) and silica (SiNP) nanoparticles has more efficient antibacterial activity than that of d-LAE alone. However, unlike d-LAE, d-PD has enhanced antibacterial activity upon being coated on AuNP. The antibacterial d-AASs and their nanocomposites with nanoparticles were synthesized in an environmentally friendly manner and are expected to be valuable new antimicrobial agents against multidrug-resistant (MDR) pathogens., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

An experimental verification of an exceptional point (EP) in a stand-alone chaotic microcavity is a tough issue because as deformation parameters are fixed the traditional frequency analysis methods cannot be applied any more. Through numerical investigations with an asymmetric Reuleaux triangle microcavity (ARTM), we find that the eigenvalue difference of paired modes can approach near-zero regardless of nonorthogonality of the modes. In this case, for a definite verification of EPs in experiments, wave function coalescence should be confirmed. For this, we suggest the method of exploiting correlation of far-field patterns (FFPs), which is directly related to spatial mode patterns. In an ARTM, we demonstrate that the FFP correlation of paired modes can be used to confirm wave function coalescence when an eigenvalue difference approaches near zero.

Internet gaming disorder (IGD) has become an important social and psychiatric issue in recent years. To prevent IGD and provide the appropriate intervention, an accurate prediction method for identifying IGD is necessary. In this study, we investigated machine learning methods of multimodal neuroimaging data including Positron Emission Tomography (PET), Electroencephalography (EEG), and clinical features to enhance prediction accuracy. Unlike the conventional methods which usually concatenate all features into one feature vector, we adopted a multiple-kernel support vector machine (MK-SVM) to classify IGD. We compared the prediction performance of standard machine learning methods such as SVM, random forest, and boosting with the proposed method in patients with IGD ( N = 28) and healthy controls ( N = 24). We showed that the prediction accuracy of the optimal MK-SVM using three kinds of modalities was much higher than other conventional machine learning methods, with the highest accuracy being 86.5%, the sensitivity 89.3%, and the specificity 83.3%. Furthermore, we deduced that clinical variables had the highest contribution to the optimal IGD prediction model and that the other two modalities were also indispensable. We found that more efficient integration of multimodal data through kernel combination could contribute to better performance of the prediction model. This study is a novel attempt to integrate each method from different sources and suggests that integrating each method, such as self-administrated reports, PET, and EEG, improves the prediction of IGD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jeong, Lee, Kim, Gwak, Kim, Yoo, Lee and Choi.)

As structures of semiconductors become more complex and finer, the importance of an accurate measurement system has emerged. Previous studies have suggested various methodologies to improve the accuracy. However, since multiple measuring instruments are used in mass production, repeatability and reproducibility are as important as the accuracy of the values produced by predictive models. In this study, we adopted a data augmentation approach that minimizes the physical difference between multiple measuring instruments by using the domain knowledge of the spectroscopic ellipsometry (SE) field. By modeling the photodetector misalignment as polynomials and taking into account random noise, we proposed stochastic polynomial wavelength calibration (s-PWC) which can improve the percentage of the gage repeatability and reproducibility (Gage R&R) value. In experiments, the proposed methodology was applied to train the nanostructure prediction model of a three-dimensional vertical NAND Flash memories with industrial data sets. The performance improvements before and after applying the method were evaluated. Gaussian noise augmentation (GNA) and polynomial wavelength calibration (PWC) methodologies devised based on previous studies were also evaluated for relative comparison. As a result of conducting the experiments under conditions similar to the actual production environment, the average value of the percentage of Gage R&R decreased from 10.23% to 6.3% when applying the proposed method, while the GNA and PWC methodologies reduced the values to 10.01% and 7.62%, respectively. There were no significant changes in the values of coefficient of determination (R 2 ) and root mean square error (RMSE) when applying the three methods based on the data augmentation approach. In other words, applying s-PWC ensures that the predictive model produces consistent values for the same sample when it needs to infer data obtained from multiple measuring instruments, while maintaining R 2 and RMSE. Future research on data augmentation techniques by modeling differences between other physical components might extend the explanations of the methodologies to improve R 2 and RMSE of predictive models. We expect this study could provide guidelines for improving the performance of inferential models based on machine learning and SE in mass production environments.

Azides are infrared (IR) probes that are important for structure and dynamics studies of proteins. However, they often display complex IR spectra owing to Fermi resonances and multiple conformers. Isotopic substitution of azides weakens the Fermi resonance, allowing more accurate IR spectral analysis. Site-specifically 15 N-labeled aromatic azides, but not aliphatic azides, are synthesized through nitrosation. Both 15 N-labeled aromatic and aliphatic azides are synthesized through nucleophilic substitution or diazo-transfer reaction but as an isotopomeric mixture. We present the synthesis of TfNN 15 N, a γ- 15 N-labeled diazo-transfer reagent, and its use to prepare β- 15 N-labeled aliphatic as well as aromatic azides., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

We reveal that non-Hermitian lossy couplings in an inter-cavity light transfer process are crucial for an optimum light transfer, unlike the prevailed belief. Our results turn out the fact that the light transfer can have multiple maxima following the increased inter-cavity distance. To validate this finding both in the weak and strong coupling regimes, we demonstrate our claim in the vicinity of the so-called exceptional point. We believe our results can contribute to realizing coupled-optical-cavity-based devices which is functional with an ultra-efficient light transfer, especially when the device scale is as small as the operation wavelength.

A formation of second-order non-Hermitian degeneracies, called exceptional points (EPs), in a chaotic oval-shaped dielectric microdisk is studied. Different symmetric optical modes localized on a stable period-3 orbit coalesce to form chiral EPs. Unlike a circular microdisk perturbed by two scatterers (CTS), our proposed system requires only one scatterer to build chiral EPs. The scatterer positions for counterpropagating EP modes are far distant from one another and almost steady against varying scatterer sizes in contrast to the CTS case. Our results can contribute to establishing a more solid platform for EP-based-device applications with flexibility and easy feasibility in obtaining EPs.

We study a lasing of mode groups in a fully chaotic rounded D-shape InGaAsP semiconductor microcavity laser when an electrode is smaller than a cavity (inward gap). Although there are numerous unstable periodic orbits supporting resonances, a mode group localized on period-5 unstable periodic orbit is more competitive than the others for our laser configuration of the inward gap. By means of theoretical and numerical analyses with ray and wave dynamics, we show that the analyses well agree with our experimental results.

The lowest threshold lasing mode in a rounded D-shape microcavity is theoretically analyzed and experimentally demonstrated. To identify the lowest threshold lasing mode, we investigate threshold conditions of different periodic orbits by considering the linear gain condition due to the effective pumping region and total loss consisting of internal and scattering losses in ray dynamics. We compare the ray dynamical result with resonance mode analysis, including gain and loss. We find that the resonance modes localized on the pentagonal marginally unstable periodic orbit have the lowest threshold in our fabrication configuration. Our findings are verified by obtaining the path lengths and far-field patterns of lasing modes.

Food fraud, including adulteration, addition, tampering, and misrepresentation of food ingredients and packaging for improper economic profit, has been global concerns affecting public health and safety. In South Korea, counterfeit expression of solar salt has been a problem causing improper economic profit, especially for those products produced from China, but labeled as 'domestics'. In this study, we were tried to discriminate geographical origins of solar salt between South Korea and China through various analytical techniques, the determination of moisture and sodium chloride contents, multi-elemental analysis, and isotope analysis. With the application of a statistical analysis, more than 93.3% of discrimination capability of positive classification was achieved in this study., (© The Korean Society of Food Science and Technology 2019.)

Rationale: Pesticide self-poisoning is a major method of suicide in many agricultural communities worldwide. In addition, there are a number of known crime cases related to people being harmed by insecticides. Methomyl, a prohibited insecticide in the Republic of Korea, has high toxicity and is frequently used for self-poisoning. In this study, we investigated the source of origin of methamyl in a fatal poisoning case using stable isotope ratio analysis., Methods: Two bottles of Soju from a crime scene were seized and nine different brands of methomyl products were collected from the neighborhood for analysis. In addition, the gastric contents and energy drink from the person who had committed suicide were analyzed. Isotope analysis using GC/Isolink/IRMS was conducted to determine the source of the methomyl by comparing their carbon and nitrogen isotope ratios. Linear discriminant analysis was utilized to verify the results., Results: Isotope ratio analysis showed that the isotope ratio ranges of methomyl found in the Soju, the gastric contents of the suicide victim, and the energy drink bottle were similar to those of a seized methomyl product, Samgong methomyl 2011 (SG11). Thus, it was assumed that SG11 was used in this fatal poisoning case., Conclusions: This study demonstrates the potential of stable isotope ratio analysis for the determination of insecticide origin in fatal poisoning cases., (Copyright © 2017 John Wiley & Sons, Ltd.)

The recent propagation of new psychoactive substances (NPS) has led to the development of new techniques for the rapid characterization of controlled substances in this category. A commercial bench-top ion mobility spectrometer (IMS) with a (63) Ni ionization source and a direct analysis in real time (DART) coupled to quadrupole time-of-flight (QTOF) were used for the rapid characterization of 35 NPS. The advantages of these techniques are fast response, ease of operation, and minimal sample preparation. The characteristic reduced mobilities of each substance are reported as are the mass spectra of the 35 compounds. The acquired product ion scan mass spectra were also compared to a library database constructed by QTOF with a electrospray ionization (ESI) source and showed a consistent relative abundance for each peak over time. A total of four seized drug samples provided by the local forensic laboratory were analyzed in order to demonstrate the utility of this approach. The results of this study suggest that both IMS and DART-QTOF are promising alternatives for the rapid screening and characterization of these new psychoactive substances., (Copyright © 2015 John Wiley & Sons, Ltd.)

Designer drugs are analogues or derivatives of illicit drugs with a modification of their chemical structure in order to circumvent current legislation for controlled substances. Designer drugs of abuse have increased dramatically in popularity all over the world for the past couple of years. Currently, the qualitative seized-drug analysis is mainly performed by gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) in which most of these emerging designer drug derivatives are extensively fragmented not presenting a molecular ion in their mass spectra. The absence of molecular ion and/or similar fragmentation pattern among these derivatives may cause the equivocal identification of unknown seized-substances. In this study, the qualitative identification of 34 designer drugs, mainly synthetic cannabinoids and synthetic cathinones, were performed by gas chromatography-triple quadrupole-tandem mass spectrometry with two different ionization techniques, including electron ionization (EI) and chemical ionization (CI) only focusing on qualitative seized-drug analysis, not from the toxicological point of view. The implementation of CI source facilitates the determination of molecular mass and the identification of seized designer drugs. Developed multiple reaction monitoring (MRM) mode may increase sensitivity and selectivity in the analysis of seized designer drugs. In addition, CI mass spectra and MRM mass spectra of these designer drug derivatives can be used as a potential supplemental database along with EI mass spectral database., (Copyright © 2014 John Wiley & Sons, Ltd.)

Objectives: This study aimed to evaluate occupational symptoms and chemical exposures of nail salon technicians., Methods: Work-related symptoms of nail salon technicians in Daegu City were surveyed using a researcher-administered questionnaire, and responses were compared to those of non-exposed office workers as controls. Personal exposure level of airborne volatile organic compounds was also monitored using passive samplers., Results: A total of 159 subjects in 120 salons were interviewed. Average work-shift concentrations of 13 chemicals were measured for 50 workers from 30 salons using personal passive samplers. The most frequently reported respiratory or neurologic symptoms by nail shop technicians compared to controls were nose irritation (odds ratio [OR], 54.0; confidence interval [CI], 21.6 to 134.8), followed by headache (OR, 9.3; CI, 4.7 to 18), and throat irritation (OR, 4.3; CI, 2.2 to 8.5). For eyes and skin, 92% of respondents complained eye irritation (OR, 13.1; CI, 5.7 to 30.1). In musculoskeletal symptoms, workers reported pain or discomfort in shoulders (OR, 20.3; CI, 7.7 to 54) and neck (OR, 19.7; CI, 8.9 to 43.6). From personal measurements, the proportion of exceeding the Korean Occupational Exposure Limit was the highest for acetone with 64%, followed by toluene (50%), butyl acetate (46%), and methyl methacrylate (12%). However, the service was being provided without a proper ventilation system in most surveyed shops., Conclusions: Based on these findings, it is warranted to have appropriate local exhaust ventilation place to ensure adequate health protection of nail shop technicians as well as customers. At the same time, greater policy interests are warranted in nail care business to protect health of both workers and customers.

The interaction between succinate-ubiquinone and ubiquinol-cytochrome c reductases in the purified, dispersed state and in embedded phospholipid vesicles was studied by differential scanning calorimetry and by electron paramagnetic resonance (EPR). When the purified, detergent-dispersed succinate-ubiquinone reductase, ubiquinol-cytochrome c reductase, and cytochrome c oxidase undergo thermodenaturation, they show an endothermic transition. However, when these isolated electron-transfer complexes are embedded in phospholipid vesicles, they undergo exothermodenaturation. The energy released could result from the collapse of the strained interaction between unsaturated fatty acyl groups of phospholipids and an exposed area of the complex formed by removal of interacting proteins. The exothermic enthalpy change of thermodenaturation of a protein-phospholipid vesicle containing both succinate-ubiquinone and ubiquinol-cytochrome c reductases was smaller than that of a mixture of protein-phospholipid vesicles formed from the individual electron-transfer complexes. This suggests specific interaction between succinate-ubiquinone reductase and ubiquinol-cytochrome c reductase in the membrane. This idea is supported by saturation transfer EPR studies showing that the rotational correlation time of spin-labeled ubiquinol-cytochrome c reductase is increased when mixed with succinate-ubiquinone reductase prior to embedding in phospholipid vesicles. These results indicate that succinate-ubiquinone reductase and ubiquinol-cytochrome c reductase are indeed present in the membrane as a supermacromolecular complex. No such supermacromolecular complex is detected between NADH-ubiquinone and ubiquinol-cytochrome c reductases or between succinate-ubiquinone and NADH-uniquinone reductases.

The interaction between cytochrome c oxidase and phospholipids was studied by differential scanning calorimetry. The active, lipid-sufficient cytochrome c oxidase undergoes thermodenaturation at 336 K with a relatively broad and concentration dependent endothermic transition. The delipidated enzyme shows an endothermic denaturation temperature at 331.3 K. When the delipidated cytochrome c oxidase was treated with chymotrypsin, a lowered thermodenaturation temperature was observed. When the delipidated cytochrome c oxidase was reconstituted with asolectin to form a functionally active enzyme complex, the thermodenaturation shifted to a higher temperature, with a sharper transition thermogram. The increase in thermotransition temperature and enthalpy change of thermodenaturation of the asolectin-reconstituted enzyme is directly proportionate to the amount of asolectin used, up to 0.5 mg asolectin per mg protein. The thermotransition temperature and enthalpy changes of thermodenaturation for the phospholipid-reconstituted cytochrome c oxidase are affected by the phospholipid headgroup and the fatty acyl groups. Among phospholipids with the same acyl moiety but different head groups, phosphatidylethanolamine was found to be more effective than phosphatidylcholine in protecting cytochrome c oxidase from thermodenaturation. An exothermic transition thermogram was observed for delipidated cytochrome c oxidase embedded in phospholipid vesicles formed with phospholipids containing unsaturated fatty acyl groups. The increase in exothermic transition temperature and exothermic enthalpy change of thermodenaturation of the oxidase-cytochrome c-cytochrome c oxidase complex destabilized cytochrome c but not cytochrome c oxidase toward thermodenaturation.

Dibromothymoquinone (DBMIB) inhibits antimycin A-sensitive ubiquinol-cytochrome c reductase activity; the maximal inhibition is 90%. DBMIB alters the EPR spectra of reduced iron-sulfur protein in intact ubiquinol-cytochrome c reductase. The maximal spectral change occurs with 60 mol inhibitor per mol cytochrome c1 in the reductase. DBMIB causes little alteration in the EPR characteristics of iron-sulfur protein when ubiquinol-cytochrome c reductase is delipidated. When delipidated ubiquinol-cytochrome c reductase is replenished with phospholipid, the effect of DBMIB reappears. However, when DBMIB is added to delipidated protein prior to replenishment with phospholipid, very little spectral alteration is observed. DBMIB does not alter the EPR spectra of purified iron-sulfur protein, with or without phospholipid in the preparation. Reduced DBMIB does not alter the EPR characteristics of iron-sulfur protein in intact or delipidated ubiquinol-cytochrome c reductase. Cysteine and other thiol compounds can reverse the spectral alternation caused by DBMIB. This reversal probably results from the reduction of DBMIB.

The interaction between phospholipids, ubiquinone and highly purified ubiquinol-cytochrome c reductase was studied using differential scanning calorimetry. The enzyme complex and its delipidated forms undergo thermodenaturation at 337.3 and 322.7 K, respectively. The reduced reductase is more stable toward thermodenaturation than is the oxidized enzyme. While phospholipids restored enzymatic activity to the delipidated enzyme complex and stabilized the enzyme toward thermodenaturation, ubiquinone showed little effect on the thermostability of ubiquinol-cytochrome c reductase. The effect of phospholipids on the thermotropic properties of ubiquinol-cytochrome c reductase is dependent upon the molecular properties of the phospholipid. When ubiquinol-cytochrome c reductase was embedded in closed asolectin vesicles, an exothermic transition peak was observed upon thermodenaturation. When the asolectin concentration in the reconstituted preparation was less than 0.3 mg/mg protein, an amorphous structure was observed in the electron micrograph and the preparation showed an endothermic transition upon thermodenaturation. The thermotropic properties of the enzyme-phospholipid vesicles were affected by the phospholipid head groups as well as the fatty-acyl chains, with those phospholipids having the most highly unsaturated fatty-acyl chains having the greatest effect. The energy for the exothermic transition may be derived from the collapse, upon thermodenaturation, of a strained interaction between the unsaturated fatty-acyl groups of phospholipids and protein molecules resulting from vesicle formation. The exothermic transition of the enzyme-phospholipid vesicle was abolished when cholesterol was included in the vesicles and when reductase was treated with a proteolytic enzyme prior to incorporation into the phospholipid vesicles.