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of chromatophores, which are pigmented organs. Light is reflected by the chromatophores, which consist of pigmentcontaining sacs. By controlling the muscles attached to their surroundings, cephalopods such as squids can manipulate their skin's transparency. [4][5][6][7][8][9] Inspired by the camouflage of cephalopods, there have been several studies of mimicking this ability. [5][6][7][8][9] Sun et al. reported a deformation-controlled method to harness mechano-chromisms by using optical design. [5] Wang et al. showed an electromechano-chemical response of elastomers by using electric fields. [6] Yu et al. demonstrated the adaptive system inspired from cephalopods with thermochromic materials, [7] and Rossiter et al. used the actuation with dielectric elastomers to be used as an artificial muscle to modulate the transmittance. [8] Although they demonstrated possible applications for new types of display devices, complex fabrication schemes or mechanical signals would be needed. In particular, it is difficult to mimic the behavior of the muscles on the sacs in order to control the light absorbent area of the pigments within the sacs. Herein, we propose a simple method to manipulate the light absorption area by moving pigments within asymmetric structures such as pyramids to change the transparency. Magnetic nanoparticles are used as pigments to absorb light, and they move in the confined asymmetric medium. We exploited the refractive index matching of liquids and transparent polymeric structures to avoid refraction at their interface. We control the hysteresis of transparency (ON/OFF ratio) by manipulating the ratio of magnetic particles to the disperse media. Furthermore, we designed a structure for better On/ Off ratio and demonstrated this by using 3D printing methods. This function could be used for smart windows, which can tune the transmittance of the window. Figure 1a is a schematic illustration explaining the mechanism of the transparency change in the skin of squid. A squid has chromatophores containing melatonin pigments, which absorb light. When the pigments aggregate, the area of the transparent region is increased. Conversely, when the pigments are spread out, the area that absorbs light is increased, and the skin is not transparent. [4] In a squid, a muscle contracts and promotes release of the pigment, causing the changes in the transparency and opacity of the skin. In the ideal case, the pigments should spread and condense in two dimensions. However, there are few reports to mimic this behavior. We use a 3D design to The camouflage used by cephalopods is an interesting topic in biomimetics. Squid, part of the cephalopod family, have transformable skin that can be made transparent or darkened through control of the light-absorption area. This is achieved using a muscular structure. A smart-window scheme inspired by this is developed. Magnetic nanopigments dispersed within an asymmetric pyramidal array are used and the light-absorption area is manipulated through use of a magnetic field. Refractive-i...

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Background: We analyzed our experience with descending necrotizing mediastinitis (DNM) treatment and investigated the efficacy of video-assisted thoracoscopic surgery (VATS) for mediastinal drainage. Methods: This retrospective analysis included patients who underwent surgical drainage for DNM at our hospital from 2005 to 2020. We analyzed patients' baseline characteristics, surgical data, and perioperative outcomes and compared them according to the mediastinal drainage approach among patients with type II DNM. Results: Twenty-five patients (male-to-female ratio, 18:7) with a mean age of 54.0±12.9 years were enrolled in this study. The most common infection sources were pharyngeal infections (60%). Most patients had significantly increased white blood cell counts, elevated C-reactive protein levels, and decreased albumin levels on admission. The most common DNM type was type IIB (n=16, 64%), while 5 and 4 patients had types I and IIA, respectively. For mediastinal drainage, the transcervical approach was used in 15 patients and the transthoracic approach (VATS) in 10 patients. The mean length of hospital stay was 26.5±23.8 days, and the postoperative morbidity and in-hospital mortality rates were 24% and 12%, respectively. No statistically significant differences were found among patients with type II DNM between the transcervical and VATS groups. However, the VATS group showed shorter mean antibiotic therapy duration, drainage duration, and hospital stay length than the transcervical group. Conclusion: DNM manifested as severe infection requiring long-term inpatient treatment, with a mortality rate of 12%. Thus, active treatment with a multidisciplinary approach is crucial, and mediastinal drainage using VATS is considered relatively safe and effective.

Liquid mobility is ubiquitous in nature, with droplets emerging at all size scales, and artificial surfaces have been designed to mimic such mobility over the past few decades. Meanwhile, millimeter-sized droplets are frequently used for wettability characterization, even with facial mask applications, although these applications have a droplet-size target range that spans from millimeters to aerosols measuring less than a few micrometers. Unlike large droplets, microdroplets can interact sensitively with the fibers they contact with and are prone to evaporation. However, wetting behaviors at the single-microfiber level remain poorly understood. Herein, we characterized the wettability of fibrous layers, which revealed that a multiscale landscape of droplets ranged from the millimeter to the micrometer scale. The contact angle (CA) values of small droplets on pristine fibrous media showed sudden decrements, especially on a single microfiber, owing to the lack of air cushions for the tiny droplets. Moreover, droplets easily adhered to the pristine layer during droplet impact tests and then yielding widespread areas of contamination on the microfibers. To resolve this, we carved nanowalls on the pristine fibers by plasma etching, which effectively suppressed such wetting phenomena. Significantly, the resulting topographies of the microfibers managed the dynamic wettability of droplets at the multiscale, which reduced the probability of contamination with impact droplets and suppressed the wetting transition upon evaporation. These findings for the dynamic wettability of fibrous media will be useful in the fight against infectious droplets.

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Background/ObjectiveEye–hand coordination, which is essential for activities of daily living, develops with age. The objective of this study was to investigate the temporal patterns of visual fixation coupled with hands during manual action on objects in children and young adults.MethodsTwelve eight-year-old children and 12 young adults performed the Jebsen–Taylor Hand Function Test (JTT) wearing eye-tracking glasses. The interval from the eye arrival time to the hand arrival time on an object was measured as eye–hand arrival span. The interval between the eye departure time and the hand departure time from the object was measured as eye–hand departure span. Eye–hand arrival span, eye–hand departure span and the performance time to complete the JTT were compared between children and young adults. Correlation between eye–hand arrival span and eye–hand departure span was analysed to identify the mechanism of eye–hand coordination.ResultsCompared with young adults, children showed longer performance time but shorter eye–hand arrival span and eye–hand departure span in the JTT. The difference in mean eye–hand arrival span of overall JTT between children and young adults was significant for both hands, whereas differences in the mean eye–hand departure span on the overall JTT and the total performance time were significant for the non-dominant hand. The eye–hand arrival span was positively correlated with the eye–hand departure span.ConclusionThis study demonstrated temporal differences in eye–hand coordination between children and young adults. Temporal patterns of visual fixation coupled to object manipulation could be useful information about the sensorimotor system in the field of occupational therapy.

Background: Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with cardiorespiratory failure. The serum albumin level is an important prognostic marker in critically ill patients. We evaluated the efficacy of using pre-ECMO serum albumin levels to predict 30-day mortality in patients with cardiogenic shock (CS) who underwent venoarterial (VA) ECMO. Methods: We reviewed the medical records of 114 adult patients who underwent VA-EC-MO between March 2021 and September 2022. The patients were divided into survivors and non-survivors. Clinical data before and during ECMO were compared. Results: Patients' mean age was 67.8±13.6 years, and 36 (31.6%) were female. The proportion of survival to discharge was 48.6% (n=56). Cox regression analysis showed that the pre-ECMO albumin level independently predicted 30-day mortality (hazard ratio, 0.25; 95% confidence interval [CI], 0.11-0.59; p=0.002). The area under the receiver operating characteristic curve of albumin levels (pre-ECMO) was 0.73 (standard error [SE], 0.05; 95% CI, 0.63-0.81; p<0.001; cut-off value=3.4 g/dL). Kaplan-Meier survival analysis showed that the cumulative 30-day mortality was significantly higher in patients with a pre-ECMO albumin level ≤3.4 g/dL than in those with a level >3.4 g/dL (68.9% vs. 23.8%, p<0.001). As the adjusted amount of albumin infused increased, the possibility of 30-day mortality also increased (coefficient=0.140; SE, 0.037; p<0.001). Conclusion: Hypoalbuminemia during ECMO was associated with higher mortality, even with higher amounts of albumin replacement, in patients with CS who underwent VA-ECMO. Further studies are needed to predict the timing of albumin replacement during ECMO.