Accumulated melanin in molds provides wavelength-dependent UV tolerance.

Fungal contamination poses a serious threat to public health and food safety because molds can grow under stressful conditions through melanin accumulation. Although ultraviolet (UV) irradiation is popular for inhibiting microorganisms, its effectiveness is limited by our insufficient knowledge about UV tolerance in melanin-accumulating molds. In this study, we first confirmed the protective effect of melanin by evaluating the UV sensitivity of young and mature spores. Additionally, we compared UV sensitivity between spores with accumulated melanin and spores prepared with melanin biosynthesis inhibitors. We found that mature spores were less UV-sensitive than young spores, and that reduced melanin accumulation by inhibitors led to reduced UV sensitivity. These results suggest that melanin protects cells against UV irradiation. To determine the most effective wavelength for inhibition, we evaluated the wavelength dependence of UV tolerance in a yeast (Rhodotorula mucilaginosa) and in molds (Aspergillus fumigatus, Cladosporium halotolerans, Cladosporium sphaerospermum, Aspergillus brasiliensis, Penicillium roqueforti, and Botrytis cinerea). We assessed UV tolerance using a UV-light emitting diode (LED) irradiation system with 13 wavelength-ranked LEDs between 250 and 365 nm, a krypton chlorine (KrCl) excimer lamp device, and a low pressure (LP) Hg lamp device. The inhibition of fungi peaked at around 270 nm, and most molds showed reduced UV sensitivity at shorter wavelengths as they accumulated pigment. Absorption spectra of the pigments showed greater absorption at shorter wavelengths, suggesting greater UV protection at these wavelengths. These results will assist in the development of fungal disinfection systems using UV, such as closed systems of air and water purification.

Analysis of Responses of GPT-4 V to the Japanese National Clinical Engineer Licensing Examination.

Chat Generative Pretrained Transformer (ChatGPT; OpenAI) is a state-of-the-art large language model that can simulate human-like conversations based on user input. We evaluated the performance of GPT-4 V in the Japanese National Clinical Engineer Licensing Examination using 2,155 questions from 2012 to 2023. The average correct answer rate for all questions was 86.0%. In particular, clinical medicine, basic medicine, medical materials, biological properties, and mechanical engineering achieved a correct response rate of ≥ 90%. Conversely, medical device safety management, electrical and electronic engineering, and extracorporeal circulation obtained low correct answer rates ranging from 64.8% to 76.5%. The correct answer rates for questions that included figures/tables, required numerical calculation, figure/table ∩ calculation, and knowledge of Japanese Industrial Standards were 55.2%, 85.8%, 64.2% and 31.0%, respectively. The reason for the low correct answer rates is that ChatGPT lacked recognition of the images and knowledge of standards and laws. This study concludes that careful attention is required when using ChatGPT because several of its explanations lack the correct description.

Potential of ChatGPT to Pass the Japanese Medical and Healthcare Professional National Licenses: A Literature Review.

This systematic review aimed to assess the academic potential of ChatGPT (GPT-3.5, 4, and 4V) for Japanese national medical and healthcare licensing examinations, taking into account its strengths and limitations. Electronic databases such as PubMed/Medline, Google Scholar, and ICHUSHI (a Japanese medical article database) were systematically searched for relevant articles, particularly those published between January 1, 2022, and April 30, 2024. A formal narrative analysis was conducted by systematically arranging similarities and differences between individual research findings together. After rigorous screening, we reviewed 22 articles. Except for one article, all articles that evaluated GPT-4 showed that this tool could pass each exam containing text only. However, some studies also reported that, despite the possibility to pass, the results of GPT-4 were worse than those of the actual examinee. Moreover, the newest model GPT-4V insufficiently recognized images, thereby providing insufficient answers to questions that involved images and figures/tables. Therefore, their precision needs to be improved to obtain better results.

Electromagnetic Compatibility Issues in 400-MHz-Band Wireless Medical Telemetry Systems and Their Management Using Simplified Methods for Safe Operation.

Wireless medical telemetry systems (WMTSs) are typical radio communication-based medical devices that monitor various biological parameters, such as electrocardiograms and respiration rates. In Japan, the assigned frequency band for WMTSs is 400 MHz. However, the issues accounting for poor reception in WMTS constitute major concerns. In this study, we analyzed the effects of electromagnetic interferences (EMIs) caused by other radio communication systems, the intermodulation (IM) effect, and noises generated from electrical devices on WMTS and discussed their management. The 400-MHz frequency band is also shared by other radio communication systems. We showed the instantaneous and impulsive voltages generated from the location-detection system for wandering patients and their potential to exhibit EMI effects on WMTS. Further, we presented the IM effect significantly reduces reception in WMTS. Additionally, the electromagnetic noises generated from electrical devices, such as light-emitting diode lamps and security cameras, can exceed the 400 MHz frequency band as these devices employ the switched-mode power supply and/or central processing unit and radiate wideband emissions. Moreover, we proposed and evaluated simple and facile methods using a simplified spectrum analysis function installed in the WMTS receiver and software-defined radio for evaluating the electromagnetic environment.

Trial of Converting Nursing Records into Simplified and Structured Information Utilizing ChatGPT-3.5.

In Japan, the excessive length of time required for nursing records has become a social problem. A shift to concise "bulleted" records is needed to apply speech recognition and to work with foreign caregivers. Therefore, using 96,000 descriptively described anonymized nursing records, we identified typical situations for each information source and attempted to convert them to "bulleted" records using ChatGPT-3.5(For return from the operating room, Status on return, Temperature control, Blood drainage, Stoma care, Monitoring, Respiration and Oxygen, Sensation and pain, etc.). The results showed that ChatGPT-3.5 has some usable functionality as a tool for extracting keywords in "bulleted" records. Furthermore, through the process of converting to a "bulleted" record, it became clear that the transition to a standardized nursing record utilizing the "Standard Terminology for Nursing Observation and Action (STerNOA)" would be facilitated.

Multidimensional regularity processing in music: an examination using redundant signals effect.

Music is based on various regularities, ranging from the repetition of physical sounds to theoretically organized harmony and counterpoint. How are multidimensional regularities processed when we listen to music? The present study focuses on the redundant signals effect (RSE) as a novel approach to untangling the relationship between these regularities in music. The RSE refers to the occurrence of a shorter reaction time (RT) when two or three signals are presented simultaneously than when only one of these signals is presented, and provides evidence that these signals are processed concurrently. In two experiments, chords that deviated from tonal (harmonic) and acoustic (intensity and timbre) regularities were presented occasionally in the final position of short chord sequences. The participants were asked to detect all deviant chords while withholding their responses to non-deviant chords (i.e., the Go/NoGo task). RSEs were observed in all double- and triple-deviant combinations, reflecting processing of multidimensional regularities. Further analyses suggested evidence of coactivation by separate perceptual modules in the combination of tonal and acoustic deviants, but not in the combination of two acoustic deviants. These results imply that tonal and acoustic regularities are different enough to be processed as two discrete pieces of information. Examining the underlying process of RSE may elucidate the relationship between multidimensional regularity processing in music.

Reduction of Campylobacter jejuni contamination by using UVA-LED and sodium hypochlorite on the surface of chicken meat.

Campylobacter jejuni causes gastroenteritis in humans and is a major concern in food safety. Commercially prepared chicken meats are frequently contaminated with C. jejuni, which is closely associated with the diffusion of intestinal contents in poultry processing plants. Sodium hypochlorite (NaClO) is commonly used during chicken processing to prevent food poisoning; however, its antimicrobial activity is not effective in the organic-rich solutions. In this study, we investigated the potential of a new photo-disinfection system, UVA-LED, for the disinfection of C. jejuni-contaminated chicken surfaces. The data indicated that UVA irradiation significantly killed C. jejuni and that its killing ability was significantly facilitated in NaClO-treated chickens. Effective inactivation of C. jejuni was achieved using a combination of UVA and NaClO, even in the organic-rich condition. The results of this study show that synergistic disinfection using a combination of UVA and NaClO has potential beneficial effects in chicken processing systems.

Characterization of Outer Membrane Vesicles Produced by Vibrio vulnificus.

Vibrio vulnificus (V. vulnificus) is a halophilic gram-negative bacterium that inhabits coastal warm water and induce severe diseases such as primary septicemia. To investigate the mechanisms of rapid bacterial translocation on intestinal infection, we focused on outer membrane vesicles (OMVs), which are extracellular vesicles produced by Gram-negative bacteria and deliver virulence factors. However, there are very few studies on the pathogenicity or contents of V. vulnificus OMVs (Vv-OMVs). In this study, we investigated the effects of Vv-OMVs on host cells. Epithelial cells INT407 were stimulated with purified OMVs and morphological alterations and levels of lactate dehydrogenase (LDH) release were observed. In cells treated with OMVs, cell detachment without LDH release was observed, which exhibited different characteristics from cytotoxic cell detachment observed in V. vulnificus infection. Interestingly, OMVs from a Vibrio Vulnificus Hemolysin (VVH) and Multifunctional-autoprocessing repeats-in -toxin (MARTX) double-deletion mutant strain also caused cell detachment without LDH release. Our results suggested that the proteolytic function of a serine protease contained in Vv-OMVs may contribute to pathogenicity of V. vulnificus by assisting bacterial translocation. This study reveals a new pathogenic mechanism during V. vulnificus infections. J. Med. Invest. 71 : 102-112, February, 2024.

Decoding predicted musical notes from omitted stimulus potentials.

Electrophysiological studies have investigated predictive processing in music by examining event-related potentials (ERPs) elicited by the violation of musical expectations. While several studies have reported that the predictability of stimuli can modulate the amplitude of ERPs, it is unclear how specific the representation of the expected note is. The present study addressed this issue by recording the omitted stimulus potentials (OSPs) to avoid contamination of bottom-up sensory processing with top-down predictive processing. Decoding of the omitted content was attempted using a support vector machine, which is a type of machine learning. ERP responses to the omission of four target notes (E, F, A, and C) at the same position in familiar and unfamiliar melodies were recorded from 25 participants. The results showed that the omission N1 were larger in the familiar melody condition than in the unfamiliar melody condition. The decoding accuracy of the four omitted notes was significantly higher in the familiar melody condition than in the unfamiliar melody condition. These results suggest that the OSPs contain discriminable predictive information, and the higher the predictability, the more the specific representation of the expected note is generated.

Development of a standard evaluation method for microbial UV sensitivity using light-emitting diodes.

Ultraviolet (UV) light is an effective disinfection method. In particular, UV light-emitting diodes (UV-LEDs) are expected to have many applications as light sources owing to their compact form factor and wide range of choices of wavelengths. However, the UV sensitivity of microorganisms for each UV wavelength has not been evaluated comprehensively because standard experimental conditions based on LED characteristics have not been established. Therefore, it is necessary to establish a standard evaluation method based on LED characteristics. Here, we developed a new UV-LED device based on strictly controlled irradiation conditions using LEDs for each wavelength (250-365 nm), checked the validity of the device characteristics and evaluated the UV sensitivity of Escherichia coli using this new evaluation method. For this new device, we considered accurate irradiance, accurate spectra, irradiance uniformity, accurate dose, beam angle, surrounding material reflections, and sample condition. From our results, the following UV irradiation conditions were established as standard: 1 mW/cm2 irradiance, bacterial solution with absorbance value of A600 = 0.5 diluted 10 times solution, solution volume of 1 mL, working distance (WD) of 100 mm. In order to compare the effects of irradiation under uniform conditions on inactivation of microorganisms, we assessed inactivation effect of E. coli by LED irradiation at each wavelength using the U280 LED as a standard wavelength. The inactivation effect for U280 LED irradiation was -0.95 ± 0.21 log at a dose of 4 mJ/cm2. Under this condition of dose, our results showed a high wavelength dependence of the inactivation effect at each UV wavelength peaking at 267 nm. Our study showed that this irradiation system was validated for the standard UV irradiation system and could be contributed to the establishment of food and water hygiene control methods and the development of equipment for the prevention of infectious diseases.

Relationship between schematic and dynamic expectations of melodic patterns in music perception.

Prediction is fundamental in music listening. Two types of expectations have been proposed: schematic expectations, which arise from knowledge of tonal regularities (e.g., harmony and key) acquired through long-term plasticity and learning, and dynamic expectations, which arise from short-term regularity representations (e.g., rhythmic patterns and melodic contours) extracted from ongoing musical contexts. Although both expectations are indispensable in music listening, how they interact with each other in music prediction remains unclear. The present study examined the relationship between schematic and dynamic expectations in music processing using event-related potentials (ERPs). At the ending note of the melodies, the schematic expectation was violated by presenting a note with music-syntactic irregular (i.e., outof- key note), while the dynamic expectation was violated by presenting a contour deviant based on online statistical learning of melodic patterns. Schematic and dynamic expectations were manipulated to predict the same note. ERPs were recorded for the music-syntactic irregularity and the contour deviant, which occurred independently or simultaneously. The results showed that the music-syntactic irregularity elicited an early right anterior negativity (ERAN), reflecting the prediction error in the schematic expectation, while the contour deviant elicited a mismatch negativity (MMN), reflecting the prediction error in the dynamic expectation. Both components occurred within a similar latency range. Moreover, the ERP amplitude was multiplicatively increased when the irregularity and deviance occurred simultaneously. These findings suggest that schematic and dynamic expectations function concurrently in an interactive manner when both expectations predict the same note.

Effects of the cardiac cycle on auditory processing: A preregistered study on mismatch negativity.

The systolic and diastolic phases of the cardiac cycle are known to affect perception and cognition differently. Higher order processing tends to be facilitated at systole, whereas sensory processing of external stimuli tends to be impaired at systole compared to diastole. The current study aims to examine whether the cardiac cycle affects auditory deviance detection, as reflected in the mismatch negativity (MMN) of the event-related brain potential (ERP). We recorded the intensity deviance response to deviant tones (70 dB) presented among standard tones (60 or 80 dB, depending on blocks) and calculated the MMN by subtracting standard ERP waveforms from deviant ERP waveforms. We also assessed intensity-dependent N1 and P2 amplitude changes by subtracting ERPs elicited by soft standard tones (60 dB) from ERPs elicited by loud standard tones (80 dB). These subtraction methods were used to eliminate phase-locked cardiac-related electric artifacts that overlap auditory ERPs. The endogenous MMN was expected to be larger at systole, reflecting the facilitation of memory-based auditory deviance detection, whereas the exogenous N1 and P2 would be smaller at systole, reflecting impaired exteroceptive sensory processing. However, after the elimination of cardiac-related artifacts, there were no significant differences between systole and diastole in any ERP components. The intensity-dependent N1 and P2 amplitude changes were not obvious in either cardiac phase, probably because of the short interstimulus intervals. The lack of a cardiac phase effect on MMN amplitude suggests that preattentive auditory processing may not be affected by bodily signals from the heart.

Statistical Learning of Chord-Transition Regularities in a Novel Equitempered Scale: An MMN Study.

In music and language domains, it has been suggested that patterned transitions of sounds can be acquired implicitly through statistical learning. Previous studies have investigated the statistical learning of auditory regularities by recording early neural responses to a sequence of tones presented at high or low transition probabilities. However, it remains unclear whether the statistical learning of musical chord transitions is reflected in endogenous, regularity-dependent components of the event-related potential (ERP). The present study aimed to record the mismatch negativity (MMN) elicited by chord transitions that deviated from newly learned transitional regularities. Chords were generated in a novel 18 equal temperament pitch class scale to avoid interference from the existing tonal representations of the 12 equal temperament pitch class system. Thirty-six adults without professional musical training listened to a sequence of randomly inverted chords in which certain chords were presented with high (standard) or low (deviant) transition probabilities. An irrelevant timbre change detection task was assigned to make them attend to the sequence during the ERP recording. After that, a familiarity test was administered in which the participants were asked to choose the more familiar chord sequence out of two successive sequences. The results showed that deviant transitions elicited the MMN, although the participants could not recognize the standard transition beyond the level of chance. These findings suggest that humans can statistically learn new transitional regularities of chords in a novel musical scale, even though they did not recognize them explicitly. This study provides further evidence that music-syntactic regularities can be acquired implicitly through statistical learning.

Characteristic Metabolic Changes in Skeletal Muscle Due to Vibrio vulnificus Infection in a Wound Infection Model.

Vibrio vulnificus is a bacterium that inhabits warm seawater or brackish water environments and causes foodborne diseases and wound infections. In severe cases, V. vulnificus invades the skeletal muscle tissue, where bacterial proliferation leads to septicemia and necrotizing fasciitis with high mortality. Despite this characteristic, information on metabolic changes in tissue infected with V. vulnificus is not available. Here, we elucidated the metabolic changes in V. vulnificus-infected mouse skeletal muscle using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Metabolome analysis revealed changes in muscle catabolites and energy metabolites during V. vulnificus infection. In particular, succinic acid accumulated but fumaric acid decreased in the infected muscle. However, the virulence factor deletion mutant revealed that changes in metabolites and bacterial proliferation were abolished in skeletal muscle infected with a multifunctional-autoprocessing repeats-in-toxin (MARTX) mutant. On the other hand, mice that were immunosuppressed via cyclophosphamide (CPA) treatment exhibited a similar level of bacterial counts and metabolites between the wild type and MARTX mutant. Therefore, our data indicate that V. vulnificus induces metabolic changes in mouse skeletal muscle and proliferates by using the MARTX toxin to evade the host immune system. This study indicates a new correlation between V. vulnificus infections and metabolic changes that lead to severe reactions or damage to host skeletal muscle. IMPORTANCE V. vulnificus causes necrotizing skin and soft tissue infections (NSSTIs) in severe cases, with high mortality and sign of rapid deterioration. Despite the severity of the infection, the dysfunction of the host metabolism in skeletal muscle triggered by V. vulnificus is poorly understood. In this study, by using a mouse wound infection model, we revealed characteristic changes in muscle catabolism and energy metabolism in skeletal muscle associated with bacterial proliferation in the infected tissues. Understanding such metabolic changes in V. vulnificus-infected tissue may provide crucial information to identify the mechanism via which V. vulnificus induces severe infections. Moreover, our metabolite data may be useful for the recognition, identification, or detection of V. vulnificus infections in clinical studies.

Relationship between early neural responses to syntactic and acoustic irregularities in music.

Humans can detect various anomalies in a sound sequence without attending to each dimension explicitly. Event-related potentials (ERPs) have been used to examine the processes of auditory deviance detection. Previous research has shown that music-syntactic anomalies elicit early right anterior negativity (ERAN), whereas more general acoustic irregularities elicit mismatch negativity (MMN). Although these ERP components occur in a similar latency range with a similar scalp topography, the relationship between the detection processes they reflect remains unclear. This study compared these components by manipulating music-syntactic (chord progression) and acoustic (intensity) irregularities orthogonally in two experiments. Non-musicians (Experiment 1: N = 39; Experiment 2: N = 24) were asked to listen to chord sequences, each consisting of 5 four-voice chords, as they watched a silent video clip. Standard, harmonic-deviant, intensity-deviant and double-deviant chords occurred at the final position in each sequence. Deviant stimuli were presented infrequently (p = .10) in Experiment 1 and equiprobably (p = .25) in Experiment 2. Regardless of deviance probability, both harmonic and intensity deviants elicited similar negativities, which were indistinguishable in terms of latency or scalp distribution. When the two deviant types occurred simultaneously, the negativity increased in an additive manner; that is, the amplitude of the double-deviant ERP was as large as the sum of the single-deviant ERPs. These findings suggest that the detection of music-syntactic and acoustic irregularities works independently, based on different regularity representations.

Perceptions About Nursing Practice Based on the Internet of Things: A Survey of Nursing Managers.

The purpose of this study was to investigate the perceptions of nursing managers about adopting nursing practices based on the Internet of Things and to examine related ethical issues. Questionnaires were sent to 538 nursing managers in Japan, with 131 responses. Of these, 87% and 33% agreed that a system using radio frequency identifiers would be useful for locating patients and nurses, respectively, 58%-81% recognized the value for patient safety of various camera systems for nursing observation, such as cameras linked to biometric alarms, 73% agreed the usefulness of automatically prioritizing alarms, but only around 39% were in favor of using facial recognition to help nursing observation. Many nursing managers expressed concerns about privacy. Data storage for at least 6 months was supported by 53% for location data and 41% for ceiling camera videos. Thus, nursing practice based on the Internet of Things is widely accepted in Japan.

Auditory perceptual processing during musical imagery: An event-related potential study.

The perceptual processing of a sound is facilitated when the sound matches auditory imagery. Previous studies have shown that auditory imagery and actual sound activate the auditory cortex in a similar fashion. To investigate whether auditory imagery is a modality-specific representation or an amodal representation, the current study examined how watching silent music videos affected the auditory processing of sound excerpts. Twenty university students were asked to form musical imagery of Japanese popular songs while watching the official music videos. Event-related brain potentials were recorded in response to short sound excerpts from the on-screen video or from a different video. The results showed that the amplitude of the exogenous N1 component (90-110 ms) was smaller for imagery-matched than for unmatched sound excerpts. The electrical source of the difference was estimated in the auditory cortex. After the N1, the matched excerpts elicited a larger late positive potential (400-800 ms) than the unmatched excerpts. These findings suggest that auditory imagery involves modality-specific neural processing and that imagery-matched sounds are processed efficiently at an early stage, inducing additional cognitive processing at a later stage.

Electromagnetic Compatibility of 400 MHz Radio Communications in Hospitals: Safety Management of Wireless Medical Telemetry.

The electromagnetic compatibility (EMC) of 400 MHz radio communications is an issue of growing interest, especially the EMC of wireless medical telemetry (WMT) in clinical settings. Electromagnetic interference (EMI) by radiation noise emitted from switched-mode power supplies built into light-emitting diode (LED) lights is now of considerable interest for the safe operation of WMT. Moreover, the 400 MHz frequency bands that are allocated for WMT are also shared and used for other radio communication systems. In this work, we studied the EMI problem of WMT used in Japan. We experimentally investigated EMI with WMT caused by electromagnetic noise emitted from LED lights. In addition, we suggested countermeasures for these EMI issues and the management of an electromagnetic environment by a very simplified method.

Evaluation of Electromagnetic Fields in a Hospital for Safe Use of Electronic Medical Equipment.

Establishment of electromagnetic compatibility is important in use of electronic medical equipment in hospitals. To evaluate the electromagnetic environment, the electric field intensity induced by electromagnetic radiation in broadcasting spectra coming from outside the hospital was measured in a new hospital building before any patients visited the hospital and 6 months after the opening of the hospital. Various incoming radio waves were detected on the upper floors, with no significant difference in measured levels before and after opening of the hospital. There were no cellphone terminal signals before the hospital opened, but these signals were strongly detected at 6 months thereafter. Cellphone base stations signals were strongly detected on the upper floors, but there were no signals at most locations in the basement and in the center of the building on the lower floors. A maximum electrical intensity of 0.28 V/m from cellphone base stations (2.1 GHz) was detected at the south end of the 2nd floor before the hospital opened. This value is lower than the EMC marginal value for general electronic medical equipment specified in IEC 60601-1-2 (3 V/m). Therefore, electromagnetic interference with electronic medical equipment is unlikely in this situation. However, cellphone terminal signals were frequently detected in non-base station signal areas. This is a concern, and understanding signal strength from cellphone base stations at a hospital is important for promotion of greater safety.

Insight into the mechanism of end-of-day far-red light (EODFR)-induced shade avoidance responses in Arabidopsis thaliana.

Shade avoidance responses are changes in plant architecture to reduce the part of a body that is in the shade in natural habitats. The most common warning signal that induces shade avoidance responses is reduction of red/far-red light ratio perceived by phytochromes. A pair of basic helix-loop-helix transcription factors, named PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) and PIF5, is crucially involved in the shade avoidance-induced hypocotyl elongation in Arabidopsis thaliana. It has been recently reported that PIF7 also plays a role in this event. Here, we examined the involvement of these PIFs in end-of-day far-red light (EODFR) responses under light and dark cycle conditions. It was shown that PIF7 played a predominant role in the EODFR-dependent hypocotyl elongation. We propose the mechanism by which PIF7 together with PIF4 and PIF5 coordinately transcribes a set of downstream genes to promote elongation of hypocotyls in response to the EODFR treatment.