Peak risk of SARS-CoV-2 infection within 5 s of face-to-face encounters: an observational/retrospective study.

The link between aerosol dynamics and viral exposure risk is not fully understood, particularly during movement and face-to-face interactions. To investigate this, we employed Particle Trace Velocimetry with a laser sheet and a high-speed camera to measure microparticles from a human mannequin's mouth. The average peak time in the non-ventilated condition (expiratory volume, 30 L; passing speed, 5 km/h) was 1.33 s (standard deviation = 0.32 s), while that in the ventilated condition was 1.38 s (standard deviation = 0.35 s). Our results showed that the peak of viral exposure risk was within 5 s during face-to-face encounters under both ventilated and non-ventilated conditions. Moreover, the risk of viral exposure greatly decreased in ventilated conditions compared to non-ventilated conditions. Based on these findings, considering a risk mitigation strategy for the duration of 5 s during face-to-face encounters is expected to significantly reduce the risk of virus exposure in airborne transmission.

Pressure Sensors for Measuring the Grip Pressure during Kendo Attacks: Assessment of Laterality and Evidence of the Five Phases of Attack.

In Kendo, there is no consensus as to which hand should produce more pressure when attacking the opponent with the bamboo sword, let alone how to teach the pressure distribution during coaching. There is the theory that a Kendo attack can be divided into five phases, which has not entered the coaching practice, either. The aim of this study was to measure the grip pressure during Kendo attacks, investigate the pressure distribution between the two hands, and find evidence for the existence of the alleged five attack phases. We instrumented a bamboo sword with grip pressure sensors and investigated the grip pressure in 23 participants. In all attack targets and in both hands, the pressure across all attack phases was significantly different. In general, the left-hand pressure was consistently and significantly higher than the right-hand one, across all five attack phases, for the hand, head, and flank attack targets. The surprising exception was the throat target with only two attack phases, the strike phase of which showed a greater pressure in the right hand. Across all participants, the left-hand pressure was greater in 60.22-100% in any phase of the four attack targets, except for the strike phase of the throat target. Through these results, we could verify the effect of the teaching customs in Kendo, as well as provide first-time evidence of the existence of the five attack phases.

Droplet evaporation on porous fabric materials.

Droplet evaporation on porous materials is a complex dynamic that occurs with spontaneous liquid imbibition through pores by capillary action. Here, we explore water dynamics on a porous fabric substrate with in-situ observations of X-ray and optical imaging techniques. We show how spreading and wicking lead to water imbibition through a porous substrate, enhancing the wetted surface area and consequently promoting evaporation. These sequential dynamics offer a framework to understand the alterations in the evaporation due to porosity for the particular case of fabric materials and a clue of how face masks interact with respiratory droplets.

[The psychological process and its longitudinal of family caregivers involved in associations for families of dementia patients].

AIM: This study aimed to explore the psychological and dynamic process of modification and evaluate its time-series peculiarity in family caregivers involved in associations for the families of dementia patients. METHODS: The current study included 39 family caregivers involved in two associations for the families of dementia patients. Five-year free group conversations in the family caregivers were recorded and converted into a verbatim record. The KJ method was then used to encode and group the verbatim record. After analyzing grouped terms and structuring the psychological and dynamic process of modification, time periods of the psychological status were determined based on the psychological process and the time-oriented perspective. The verbatim record extracted by the KJ method was analyzed by text-mining and a cluster analysis in order to assess validity of the psychological process and its time division. In addition, the appearance ratio of the texts extracted in each time period were analyzed to determine the longitudinal peculiarity in the psychological and dynamic process. RESULTS: The psychological process of family caregivers was classified broadly into four components: (1) recognizing and identifying problems, (2) seeking help and dealing with problems, (3) remedying and evaluating problems, and (4) feeling effective and empowering oneself to overcome problems. The validity of the psychological process and its time division was supported by text-mining and a cluster analysis. The appearance ratio of the texts extracted in each time period was quasi-periodic and recursive rather than transient. CONCLUSIONS: The psychological and dynamic process elucidated in the current study consists of four major components participants experience when involved in associations for the families of dementia patients. Although this process may not have originated in associations for the families of dementia patients, a quasi-periodic and recursive tendency in the appearance ratio of extracted texts is a notable feature. In dementia care, it is vital to foresee emerging challenges on a constant basis and attempt precedent, forecasting-type care. Being involved in associations for the families of dementia patients facilitates the administration of forecasting-type care.

Aerodynamics of the newly approved football for the English Premier League 2020-21 season.

Footballs are typically constructed with 32 panels. Recently, the number of panels has been successively reduced to 14, 8, and 6 panels, and official balls have been adopted with complex panel shapes and aerodynamics that differ from those of 32-panel balls. The official ball for the 2020-21 season of the English Premier League comprises just four panels with a complex panel shape and surface groove design; however, its aerodynamics have not yet been clarified. This study aims to clarify the aerodynamic characteristics (drag, side force, lift force, their deviations, and critical Reynolds number) of the new 4-panel ball (Flight 2020, Nike) in comparison to a 6-panel ball (Tsubasa 2020, Adidas) and conventional 32-panel ball (Pelada 2020, Molten) using a wind tunnel test, surface design measurement, and a simple 2D flight simulation. The results showed that Flight 2020 has greater surface roughness and smaller critical Reynolds number than Pelada 2020 and Tsubasa 2020, resulting to its marginally greater drag force in the supercritical region, and slightly smaller fluctuations of the side and lift forces. Furthermore, Flight with a symmetrical orientation exhibits a significantly higher drag coefficient in the supercritical region, suggesting its greater air resistance during flight under this condition.

Aerodynamic effects of dimples on soccer ball surfaces.

Recently, the shape and design of the panel on the official ball used in the FIFA World Cup was considerably different from that of a conventional soccer ball (having 32 pentagonal and hexagonal panels). Depending on the number of different panels and their orientation, the aerodynamic force experienced by a ball is believed to change, which in turn changes the ball trajectory. However, not much is known about the impact of the surface forms of a ball on its aerodynamics. Therefore, in the present study, 10 different types of soccer balls were produced and their aerodynamic properties were studied by wind tunnel experiments. The results confirmed that the aerodynamic force acting on the ball varied considerably depending on the existence of dimples on the ball surface. In addition, the 4 types of soccer balls, which had different kinds of roughness, revealed that even balls having the same number and shapes of panels experienced greatly varying aerodynamic forces depending on the surface form of the balls.

Visualization of air flow around soccer ball using a particle image velocimetry.

A traditional soccer ball is constructed using 32 pentagonal and hexagonal panels. In recent years, however, the likes of the Teamgeist and Jabulani balls, constructed from 14 and 8 panels, respectively, have entered the field, marking a significant departure from conventionality in terms of shape and design. Moreover, the recently introduced Brazuca ball features a new 6-panel design and has already been adopted by many soccer leagues. However, the shapes of the constituent panels of these balls differ substantially from those of conventional balls. Therefore, this study set out to investigate the flight and aerodynamic characteristics of different orientations of the soccer ball, which is constructed from panels of different shapes. A wind tunnel test showed substantial differences in the aerodynamic forces acting on the ball, depending on its orientation. Substantial differences were also observed in the aerodynamic forces acting on the ball in different directions, corresponding to its orientation and rotation. Moreover, two-dimensional particle image velocimetry (2D-PIV) measurements showed that the boundary separation varies depending on the orientation of the ball. Based on these results, we can conclude that the shape of the panels of a soccer ball substantially affects its flight trajectory.

Effect of panel shape of soccer ball on its flight characteristics.

Soccer balls are typically constructed from 32 pentagonal and hexagonal panels. Recently, however, newer balls named Cafusa, Teamgeist 2, and Jabulani were respectively produced from 32, 14, and 8 panels with shapes and designs dramatically different from those of conventional balls. The newest type of ball, named Brazuca, was produced from six panels and will be used in the 2014 FIFA World Cup in Brazil. There have, however, been few studies on the aerodynamic properties of balls constructed from different numbers and shapes of panels. Hence, we used wind tunnel tests and a kick-robot to examine the relationship between the panel shape and orientation of modern soccer balls and their aerodynamic and flight characteristics. We observed a correlation between the wind tunnel test results and the actual ball trajectories, and also clarified how the panel characteristics affected the flight of the ball, which enabled prediction of the trajectory.

Aerodynamic drag of modern soccer balls.

Soccer balls such as the Adidas Roteiro that have been used in soccer tournaments thus far had 32 pentagonal and hexagonal panels. Recently, the Adidas Teamgeist II and Adidas Jabulani, respectively having 14 and 8 panels, have been used at tournaments; the aerodynamic characteristics of these balls have not yet been verified. Now, the Adidas Tango 12, having 32 panels, has been developed for use at tournaments; therefore, it is necessary to understand its aerodynamic characteristics. Through a wind tunnel test and ball trajectory simulations, this study shows that the aerodynamic resistance of the new 32-panel soccer ball is larger in the high-speed region and lower in the middle-speed region than that of the previous 14- and 8-panel balls. The critical Reynolds number of the Roteiro, Teamgeist II, Jabulani, and Tango 12 was ~2.2 × 10(5) (drag coefficient, C d ≈ 0.12), ~2.8 × 10(5) (C d ≈ 0.13), ~3.3 × 10(5) (C d ≈ 0.13), and ~2.4 × 10(5) (C d ≈ 0.15), respectively. The flight trajectory simulation suggested that the Tango 12, one of the newest soccer balls, has less air resistance in the medium-speed region than the Jabulani and can thus easily acquire large initial velocity in this region. It is considered that the critical Reynolds number of a soccer ball, as considered within the scope of this experiment, depends on the extended total distance of the panel bonds rather than the small designs on the panel surfaces.

Modified Collis-Nissen procedure for long gap pure esophageal atresia.

BACKGROUND/PURPOSE: Esophageal reconstruction in long gap esophageal atresia (EA) is technically challenging, and several procedures have been described. The purpose of this study is to review our experience with the modified Collis-Nissen procedure in the repair of long gap pure EA. METHODS: Six patients with pure EA were treated at our institution from 1985 to 2008. Patients' demographics, surgical technique, timing of repair, early and late complications, and long-term functional outcomes were retrospectively reviewed. RESULTS: Five primary cases and 1 redo case were included. The mean gap length was 5.3 vertebral bodies (range, 4-6). Modified Collis-Nissen procedure was performed at a mean age of 11.6 months (range, 9-14 months) in primary cases. There was 1 anastomotic leak in the redo case, which healed spontaneously. Two patients had anastomotic strictures requiring balloon dilatations. Patients were weaned from tube feeding at a mean duration of 4 months (range, 1-6 months) postoperatively. All patients have normal oral intake at the last follow-up visit. Two adult patients had normal growth and development and no digestive symptoms. Endoscopic examination and pH monitoring showed no signs of significant gastroesophageal reflux. CONCLUSIONS: Modified Collis-Nissen procedure is a good option to consider in patients with long gap pure EA and is associated with an acceptable complication rate and promising short- and long-term results.

Phase shift spectra of a fiber-microsphere system at the single photon level.

We succeeded in measuring phase shift spectra of a microsphere cavity coupled with a tapered fiber using a weak coherent probe light at the single photon level. We utilized a tapered fiber with almost no depolarization and constructed a very stable phase shift measurement scheme based on polarization analysis using photon counting. Using a very weak probe light (n = 0.41), we succeeded in observing the transition in the phase shift spectrum between undercoupling and overcoupling (at gap distances of 500 and 100 nm, respectively). We also used quantum state tomography to obtain a 'purity spectrum'. Even in the overcoupling regime, the average purity was 0.982 ± 0.024 (minimum purity: 0.892), suggesting that the coherence of the fiber-microsphere system was well preserved. Based on these results, we believe this system is applicable to quantum phase gates using single light emitters such as diamond nitrogen vacancy centers.

Fiber-microsphere system at cryogenic temperatures toward cavity QED using diamond NV centers.

The coupling of a microsphere resonator to a tapered fiber was demonstrated at cryogenic temperatures (8 - 13 K) and investigated with a probe laser light whose frequency around the zero phonon line of nitrogen vacancy centers in diamond (638 nm). For this purpose, a liquid-helium-flow cryostat with a large sample chamber is developed and a resonance dip with a Q of 2 x 10(6) is observed. The resonance frequency and the coupling condition are found to be stable for a period of one hour.

Nine constituents including six xanthone-related compounds isolated from two ascomycetes, Gelasinospora santi-florii and Emericella quadrilineata, found in a screening study focused on immunomodulatory activity.

Five metabolites tentatively called GS-1 (1)-5 (5) from Gelasinospora santi-florii, and four tentatively called EQ-4 (6), EQ-6 (7)-8 (9) together with 1-4 from Emericella quadrilineata have been isolated in a screening study on immunomodulatory fungal constituents. Among these nine metabolites, EQ-7 and 8 have been unknown. This time, the structures of GS-4 which has previously been isolated, EQ-7, and -8 have been determined to be (4R,4aS,9aR)-1,9a-dihydronidulalin A (4), (4S,4aR,9aR)-4a-carbomethoxy-1,4,4a,9a-tetrahydro-4,8-dihydroxy-6-methylxanthone (8), and 9-hydroxymicroperfuranone (9), respectively, and the six other metabolites have been identified. On bioassay, a dihydroxanthone, nidulalin A (1), a hexaketide, sordarial (5), and a xanthone, pinselin (7) have displayed significant immunosuppressive activities. The structure-activity relationships of these constituents have also been discussed.

Community discharge of patients with schizophrenia: a Japanese experience.

In Japan, admission to a psychiatric facility for people with schizophrenia is usually for life. We developed a rehabilitation program aimed at discharging these patients into the Tokyo community. This paper describes the results for the 224 patients. Using an inpatient ward at the Tokyo Musashino Hospital, patients were enrolled in the program and subsequently discharged into the community with an assigned worker. The results indicate for the majority (79%) re-integration into the community was successful. The success of this program in a metropolitan city like Tokyo argues for the efficacy of such programs.

Three-dimensional kinetic analysis of side-foot and instep soccer kicks.

PURPOSE: The purpose of this study was to identify the kinetic aspects of side-foot and instep soccer kicks to understand the different mechanics underlying the two kicks. METHODS: The motions of both kicks were captured using a three-dimensional cinematographic technique. The kicking leg was modeled as a three-link kinetic chain composed of thigh, shank, and foot, from which joint torques and angular velocities were computed. RESULTS: The ball velocity of the side-foot kick (23.4 +/- 1.7 m x s(-1)) was significantly slower than that of the instep kick (28.0 +/- 2.1 m.s(-1)). Significant differences were also observed between the two kicks for the magnitude of hip external rotation torque (56 +/- 12 N.m in the side-foot kick; 33 +/- 8 N.m in the instep kick) and hip external rotation angular velocity (11.1 +/- 2.4 rad x s(-1) in the side-foot kick; 6.0 +/- 2.0 rad x s(-1) in the instep kick). CONCLUSION: These results indicated that to hit the ball with the medial side of the foot, a complicated series of rotational motions are required for the side-foot kick. The hip external rotation torque dominantly exhibited in the side-foot kick caused the clockwise rotation of the thigh-shank plane at the later stage of kicking. This may allow the hip external rotation motion to increase directly the forward velocity of the side foot, with which players can squarely impact the ball.