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Topological defects, the fundamental entities arising from symmetry-breaking, have captivated the attention of physicists, mathematicians, and materials scientists for decades. Here we propose and demonstrate a novel method for robust control of topological defects in a liquid crystal (LC), an ideal testbed for the investigation of topological defects. A liquid layer is introduced on the LC in microwells in a microfluidic device. The liquid/LC interface facilitates the control of the LC alignment thereby introducing different molecules in the liquid/LC phase. A topological defect is robustly formed in a microwell when the liquid/LC interface and the microwell surface impose planar and homeotropic alignment, respectively. We also demonstrate the formation/disappearance of topological defects by light illumination, realized by dissolving photo-responsive molecules in the LC. Our platform that facilitates the control of LC topological defects by the introduction of different molecules and external stimuli could have potential for sensor applications.
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Insoluble particulate matter test for injections in pharmacopoeia is mandatory for parenteral drug products. In this test using light obscuration, four measurements of at least 5-mL are required. Since therapeutic protein injections of low dosage volumes are getting more popular, reduction of test volumes is desired. In this collaborative study, the impact of lower measurement volume on the accuracy and precision of particle count was evaluated using 2, 5, 10, and 25-µm polystyrene count standards for the validity of test with reduced sample volumes. Good accuracy (3000 particles/mL⯱â¯10%) was obtained at all measurement volumes, and the inter-run variability (RSD) was the same levels between 5 and 1â¯mL. Although the inter-run variability increased at 0.2â¯mL, it was below 5%. These results indicated that light obscuration method can be used with 5â¯mL-0.2â¯mL, and that it is feasible for monitoring particles ≥2⯵m.
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Técnicas de Química Analítica/métodos , Contaminación de Medicamentos/prevención & control , Estudios de Factibilidad , Material Particulado/análisis , Animales , Técnicas de Química Analítica/normas , Humanos , Tamaño de la Partícula , Material Particulado/química , Reproducibilidad de los Resultados , SolubilidadRESUMEN
INTRODUCTION: The effects of hyperbaric oxygen (HBO2) therapy on sprains, ligament injuries, and muscle strains have been reported in several animal studies. In a dog model of compartment syndrome and in a rat contused skeletal muscle injury model, the significant effects of HBO2 therapy on the reduction of edema and muscle necrosis have been reported. In basic research HBO2 therapy stimulated fibroblast activity to improve the healing process. Because of this it expected that HBO2 therapy might improve focal edema and pain in the acute phase and accelerate the healing of injured tissues in athletes with a medial collateral ligament (MCL) injury of the knee. This study aimed to examine the short-term effects of HBO2 application subjectively, and the long-term effects of HBO2 therapy in Japanese professional or semi-professional rugby players with grade 2 MCL injury of the knee. METHODS: Thirty-two professional or semi-professional rugby players with grade 2 MCL injury of the knee were investigated. First, in the HBO2 group (n=16), HBO2 therapy was performed during the acute phase. Visual analog scales (VASs) immediately before and after HBO2 therapy on the same day were compared. Next, we retrospectively evaluated the time to return to play in the HBO2 (n=16) and non-HBO2 (n=16) groups. RESULTS: VAS scores for pain while walking immediately before and after HBO2 therapy on the same day were 37.4 ± 20.1 (mean ± standard deviation) and 32.4 ± 21.8, respectively (p⟨0.001). The VAS scores for pain while jogging were 50.7 ± 25.6 and 43.9 ± 25.0, respectively (p⟨0.001). The time to return to play was 31.4 ± 12.2 days in the HBO2 group and 42.1 ± 15.8 days in the non-HBO2 group, indicating a significant difference between the groups (p⟨0.05). CONCLUSION: HBO2 therapy may reduce pain and accelerate the return to play in athletes with grade 2 MCL injury of the knee in this non-randomized study.
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Fútbol Americano/lesiones , Oxigenoterapia Hiperbárica , Ligamento Colateral Medial de la Rodilla/lesiones , Dolor Musculoesquelético/terapia , Volver al Deporte , Cicatrización de Heridas/fisiología , Adulto , Pueblo Asiatico , Estudios de Casos y Controles , Humanos , Japón , Trote , Inestabilidad de la Articulación/clasificación , Masculino , Dolor Musculoesquelético/rehabilitación , Dimensión del Dolor/métodos , Caminata , Adulto JovenRESUMEN
We investigate numerically the optical properties of a hexagonal half-Skyrmion lattice exhibited by a highly chiral liquid crystal confined between two parallel plates. Our study focuses on the near and far-field reflection for normally incident light with different polarizations. We show that, when the wavelength of the incident light is longer than a threshold value, the reflectivity is almost insensitive to the polarization of the incident light, although the intensity profiles of the reflected light, in particular in the near-field regime, depend significantly on the polarization. The former property is attributable to the quasi two-dimensional nature of the half-Skyrmion lattice, that is, almost uniform orientational order along the direction normal to the confining plates. Our results for the intensity of reflected light generated by evanescent as well as propagating contributions suggest that direct evidence of the formation and structure of half-Skyrmions could be provided by near-field optics with resolutions higher than that of conventional optical microscopy.
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Cholesteric blue phases of a chiral liquid crystal are interesting examples of self-organised three-dimensional nanostructures formed by soft matter. Recently it was demonstrated that a polymer matrix introduced by photopolymerization inside a bulk blue phase not only stabilises the host blue phase significantly, but also serves as a template for blue phase ordering. We show with numerical modelling that the transfer of the orientational order of the blue phase to the surfaces of the polymer matrix, together with the resulting surface anchoring, can account for the templating behaviour of the polymer matrix inducing the blue phase ordering of an achiral nematic liquid crystal. Furthermore, tailoring the anchoring conditions of the polymer matrix surfaces can bring about orientational ordering different from those of bulk blue phases, including an intertwined complex of the polymer matrix and topological line defects of orientational order. Optical Kerr response of templated blue phases is explored, finding large Kerr constants in the range of K = 2-10 × 10(-9) m V(-2) and notable dependence on the surface anchoring strength. More generally, the presented numerical approach is aimed to clarify the role and actions of templating polymer matrices in complex chiral nematic fluids, and further to help design novel template-based materials from chiral liquid crystals.
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The photonic band structure and transmission properties of a cholesteric blue phase II liquid crystal, which is elongated in the [100] direction by electrostriction, are analyzed by finite-difference time-domain method. The simple cubic lattice deforms into a tetragonal lattice under the influence of an electric field, resulting in a change of the photonic band structure. Moreover, we show that the circular polarization dependence of the transmittance spectrum changes in an electric field, a behavior that has yet to be observed in experiment.
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Hollow-fiber-flow field-flow fractionation (HF5) separates protein molecules on the basis of the difference in the diffusion coefficient, and can evaluate the aggregation ratio of proteins. However, HF5 is still a minor technique because information on the separation conditions is limited. We examined in detail the effect of different settings, including the main-flow rate, the cross-flow rate, the focus point, the injection amount, and the ionic strength of the mobile phase, on fractographic characteristics. On the basis of the results, we proposed optimized conditions of the HF5 method for quantification of monoclonal antibody in sample solutions. The HF5 method was qualified regarding the precision, accuracy, linearity of the main peak, and quantitation limit. In addition, the HF5 method was applied to non-heated Mab A and heat-induced-antibody-aggregate-containing samples to evaluate the aggregation ratio and the distribution extent. The separation performance was comparable with or better than that of conventional methods including analytical ultracentrifugation-sedimentation velocity and asymmetric-flow field-flow fractionation.
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Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/aislamiento & purificación , Fraccionamiento de Campo-Flujo/métodos , Agregado de Proteínas , Fraccionamiento de Campo-Flujo/instrumentación , CalorRESUMEN
Dense bacterial suspensions exhibit turbulent behavior called bacterial turbulence. The behavior of the bulk unconstrained bacterial turbulence is described well by the Toner-Tu-Swift-Hohenberg (TTSH) equation for the velocity field. However, it remains unclear how we should treat boundary conditions on bacterial turbulence in contact with some boundaries (e.g., solid walls). To be more specific, although the importance of the edge current, the flow along the boundary, has been demonstrated in several experimental studies on confined bacterial suspensions, previous numerical studies based on the TTSH equation employ nonslip boundary conditions and do not seem to properly describe the behavior of bacteria near the boundaries. In this paper, we impose a slip boundary condition on the TTSH equation to describe the bacterial motion at boundaries. We develop a method to implement the slip boundary condition. Using this method, we have successfully produced edge current and discovered that the direction of the edge current temporally oscillates. The oscillation can be attributable to the advection term in the TTSH equation. Our paper demonstrates that boundary conditions could play an important role in the collective dynamics of active systems.
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Background: We assert that the ubiquitous environmental factor in inflammatory bowel disease (IBD) is our westernized diet. Therefore, all of our newly diagnosed patients were admitted to experience a plant-based diet (PBD). In the present study, we investigated the efficacy of a PBD in pregnant women with IBD. Case Description: Included in the study were women with IBD provided with a PBD (lacto-ovo-vegetarian diet) between 2004 and 2020 who were either pregnant or became pregnant. There were 10 pregnancies in eight cases: seven cases of ulcerative colitis (UC) and one case of Crohn's disease (CD). Five active cases during pregnancy were treated. The other five cases experienced the diet before pregnancy. Two cases developed UC either during pregnancy or in the postpartum period. The PBD without medication induced remission in two mild cases of UC. Infliximab and the PBD induced remission in a relapsed case of CD. There were six conceptions during remission without medication in four cases of UC. No case relapsed during pregnancy in these cases. Vaginal, cesarean, and vacuum extraction were undertaken in four, four, and two deliveries, respectively. Three in two cases were preterm deliveries. There were 10 live births in the eight cases. Two neonates from a mother had jaundice. In the median follow-up period of 71 months, all eight cases were in the quiescent phase. PBD scores in their follow-up period, which indicate adherence to the PBD, exceeded the baseline scores. Conclusions: Our case series study indicated that a PBD was effective for pregnant women with IBD.
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An online health-monitoring system for COVID-19-infected patients who are staying in hotels and homes was developed using geographical information systems. This system provides display functions for sending health observation forms to infected residents, scoring for medical risk assessment, and centralized management. More than 1,146,000 health observation records were registered in November 2022, and the system contributed to maintaining the functionality of the municipal health center in Sapporo, Japan.
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COVID-19 , Humanos , COVID-19/epidemiología , Instituciones de Salud , Sistemas de Información Geográfica , Japón/epidemiología , Sistemas de Registros Médicos ComputarizadosRESUMEN
We numerically calculated the photonic band structure of a cholesteric blue phase II (BPII) liquid crystal using two models, the tensor order parameter model and the double-twist cylinder (DTC) model. The tensor order parameter model was derived numerically from the Landau-de Gennes theory, whereas the DTC model simply assumed a three-dimensional stack of ordered cylinders. The two models yielded similar photonic band structures; however, the polarization dependence of the transmission spectrum through the (100) direction in BPII was different. The results from the tensor order parameter model gave a better qualitative agreement with experiments on the transmission spectrum. This demonstrates the importance of a precise orientation model in the analysis of the optical properties of cholesteric blue phases.
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We investigate numerically the structure of twin boundaries of cholesteric blue phases. Our study is based on the Landau-de Gennes continuum theory describing the orientational order of the liquid crystal by a second-rank tensor. We pay particular attention to blue phase I (BP I) with body-centered-cubic symmetry and consider twin boundaries between BP I lattices in which their (110) planes are shared and the (1[over ¯]12) plane of one lattice is parallel to the (11[over ¯]2) plane of the other as observed in previous experiments [Jin et al., Sci. Adv. 6, eaay5986 (2020)10.1126/sciadv.aay5986; Zhang et al., ACS Appl. Mater. Interf. 13, 36130 (2021)1944-824410.1021/acsami.1c06873]. We discuss two plausible cases in which the twin boundaries are parallel to the {112} planes or the {111} planes. In the former, disclination lines of obtusely bent form penetrate the twin boundaries, and in the latter straight disclination lines as well as bent ones are found at the twin boundaries. The former twin boundaries are energetically less costly, consistent with previous experimental identifications. From our numerical results the free energy of a twin boundary per unit area is estimated to be ≃4×10^{-6}Jm^{-2}, which indeed indicates that the formation of twin boundaries is not prohibitively costly.
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It is highly desirable but difficult to understand how microscopic molecular details influence the macroscopic material properties, especially for soft materials with complex molecular architectures. In this study we focus on liquid crystal elastomers (LCEs) and aim at identifying the design variables of their molecular architectures that govern their macroscopic deformations. We apply the regression analysis using machine learning (ML) to a database containing the results of coarse grained molecular dynamics simulations of LCEs with various molecular architectures. The predictive performance of a surrogate model generated by the regression analysis is also tested. The database contains design variables for LCE molecular architectures, system and simulation conditions, and stress-strain curves for each LCE molecular system. Regression analysis is applied using the stress-strain curves as objective variables and the other factors as explanatory variables. The results reveal several descriptors governing the stress-strain curves. To test the predictive performance of the surrogate model, stress-strain curves are predicted for LCE molecular architectures that were not used in the ML scheme. The predicted curves capture the characteristics of the results obtained from molecular dynamics simulations. Therefore, the ML scheme has great potential to accelerate LCE material exploration by detecting the key design variables in the molecular architecture and predicting the LCE deformations.
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Elastómeros , Cristales Líquidos , Elastómeros/química , Cristales Líquidos/química , Elasticidad , Análisis de RegresiónRESUMEN
Background: Plasmalogens have been shown to improve neurodegenerative pathology and cognitive function. We hypothesized that plasmalogens work in small amounts as a kind of hormone interacting with a G protein-coupled receptor, and then explored the effects of scallop-derived purified plasmalogens on psychobehavioral conditions in a randomized placebo-controlled trial of college athletes in Japan. Methods and materials: Eligible participants were male students aged 18-22 years who belonged to university athletic clubs. They were randomly allocated to either plasmalogen (2 mg per day) or placebo treatment of 4 weeks' duration. The primary outcome was the T-score of the Profile of Mood States (POMS) 2-Adult Short, and the secondary outcomes included the seven individual scales of the POMS 2, other psychobehavioral measures, physical performance, and laboratory measurements. The trial was registered at the Japan Registry of Clinical Trials (jRCTs071190028). Results: Forty participants (20 in the plasmalogen group and 20 in the placebo group) completed the 4-week treatment. The Total Mood Disturbance (TMD) score of the plasmalogen group showed a greater decrease at 4 weeks than that of the placebo group while the between-group difference was marginally significant (p = 0.07). The anger-hostility and fatigue-inertia scores of the POMS 2 decreased significantly in the plasmalogen group, but not in the placebo group, at 4 weeks. Between-group differences in those scores were highly significant (p = 0.003 for anger-hostility and p = 0.005 for fatigue-inertia). The plasmalogen group showed a slight decrease in the Athens Insomnia Scale at 2 weeks, and the between-group difference was near-significant (p = 0.07). The elapsed time in minute patterns on the Uchida-Kraepelin test, which is a marker of mental concentration, revealed significantly greater performance in the plasmalogen group than in the placebo group. There were no between-group differences in physical and laboratory measurements. Conclusion: It is suggested that orally administered plasmalogens alleviate negative mood states and sleep problems, and also enhance mental concentration.
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We find numerically that a regular array of isolated ring defects can exist as a stable state in a highly chiral liquid crystal confined in a thin cell imposing fixed planar anchoring at the parallel confining surfaces. This peculiar defect structure can be stable when the cell thickness d is around 3/4 of the helical pitch p. A cell of thickness 3p/4 with parallel surface anchoring is incompatible with helical alignment that favors d=mp/2 (with m being an integer). Formation of ring defects can thus be regarded as a result of frustrations between the helical alignment with a specific pitch and the confining surfaces that prevent it.
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Phase transition of anisotropic materials is ubiquitously observed in physics, biology, materials science, and engineering. Nevertheless, how anisotropy of constituent molecules affects the phase transition dynamics is still poorly understood. Here we investigate numerically the phase transition of a simple model system composed of anisotropic molecules, and report on our discovery of multistep nucleation of nuclei with layered positional ordering (smectic ordering), from a fluid-like nematic phase with orientational order only (no positional order). A trinity of molecular dynamics simulation, machine learning, and molecular cluster analysis yielding free energy landscapes unambiguously demonstrates the dynamics of multistep nucleation process involving characteristic metastable clusters that precede supercritical smectic nuclei and cannot be accounted for by the classical nucleation theory. Our work suggests that molecules of simple shape can exhibit rich and complex nucleation processes, and our numerical approach will provide deeper understanding of phase transitions and resulting structures in anisotropic materials such as biological systems and functional materials.
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Crystal twinning is an intergrowth of two or more single crystals of the same species with specific crystallographic relations in their orientations. Here, we perform microscopic optical characterization of (211) twins in the three-dimensional liquid crystalline phase known as the blue phase (BP), with I4132 space group symmetry. We describe the effect of twinning on the optical diffraction pattern-Kossel pattern-of blue phases and analyze the patterns to deduce structural information such as the twin elements and the previously unnoticed deviations from the perfect cubic structure at zero electric field. Further, we obtain in situ observations as a field is applied along the [110] direction of the twinning crystals and find that the twin boundary shows a pinning effect that defines the orientation of the twinned pair through the cubic-to-orthogonal structure transformation. Our findings not only provide important insights for the application of BPs as electro-optic crystals but also present a step in understanding the hierarchical structures that are crystallographic.
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In our numerical study based on a phenomenological description of strongly confined liquid crystalline blue phase I (BP I), we find several novel structures characterized by specific configurations of topological disclination lines. The thickness of the system is of the order of the dimension of the unit cell of the bulk BP I, and the confining surfaces adopts homeotropic anchoring. The structures include an array of double-helix disclination lines accompanied by an orthorhombic lattice of double-twist cylinders, and two parallel arrays of winding disclination lines almost perpendicular to each other.
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A 50-year-old Japanese woman with Mayer-Rokitansky-Kustner-Hauser syndrome and two pelvic tumors underwent laparotomy. Laparotomy revealed that no torsion of the right ovarian tumor had occurred, with uterine leiomyoma originating from the right side of a rudimentary uterus. Histopathological examination demonstrated leiomyoma of the rudimentary uterus with positive staining for estrogen and progesterone receptors, and mucinous cyst adenoma of the right ovary. Uterine leiomyoma is rare in this syndrome and the present report represents the first published case complicated by ovarian tumor.
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Anomalías Múltiples , Cistoadenoma Mucinoso/cirugía , Genitales Femeninos/anomalías , Leiomioma/cirugía , Neoplasias Primarias Múltiples , Neoplasias Ováricas/cirugía , Neoplasias Uterinas/cirugía , Femenino , Humanos , Leiomioma/patología , Persona de Mediana Edad , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Múltiples/cirugía , Síndrome , Neoplasias Uterinas/patologíaRESUMEN
Scleroderma-like cutaneous lesion as an adverse event from paclitaxel and carboplatin has been reported. No report shows the occurrence of scleroderma-like cutaneous lesions from a single course of carboplatin. The patient is a 67-year-old female, administered paclitaxel and carboplatin as neoadjuvant chemotherapy. Following four courses, scleroderma-like cutaneous lesions were demonstrated. Skin biopsy corresponded to histopathological findings of scleroderma. Immunological investigation shows only antinuclear antibodies are positive. The characteristic Raynaud's phenomenon of scleroderma and hemorrhagic spots on the cuticles were not found. Postoperatively, a single course of carboplatin treatment was given. Scleroderma-like cutaneous lesions re-induced and worsened. This is the first report detailing scleroderma-like cutaneous lesions induced by previously administrated paclitaxel that worsened by carboplatin.