654 research outputs found

    Metal work-function-dependent barrier height of Ni contacts with metal-embedded nanoparticles to 4H-SiC

    Get PDF
    Metal, typically gold [Au], nanoparticles [NPs] embedded in a capping metal contact layer onto silicon carbide [SiC] are considered to have practical applications in changing the barrier height of the original contacts. Here, we demonstrate the use of silver [Ag] NPs to effectively lower the barrier height of the electrical contacts to 4H-SiC. It has been shown that the barrier height of the fabricated SiC diode structures (Ni with embedded Ag-NPs) has significantly reduced by 0.11 eV and 0.18 eV with respect to the samples with Au-NPs and the reference samples, respectively. The experimental results have also been compared with both an analytic model based on Tung's theory and physics-based two-dimensional numerical simulations

    Study on Personal Characteristics and Emotional Affordances through User Activity Analysis

    Get PDF
    Design methodology should address psychological and cognitive aspects based on human emotion and feeling as well as physical and functional aspects based on product structure. Donald Norman introduced perceived affordances as characteristics in the appearance of an object that gives clues for its proper operations. We conducted a case study in a public space - building lobby - used by many general people. User activities and behaviors were analyzed in several specific tasks given to twenty participants with similar cultural background in the lobby of a building they have never been to before. Then we identified affordances and building structure elements, called affordance features, critically related to those affordances. While performing the tasks in the same building lobby, user activities can be classified into several different groups for each task based on affordance features involved in their activities. These user activity differences are then compared with their personal cognitive characteristics derived from their perception and judgment preferences using intuitive and factual perception orientation and objective and subjective decision making inclination respectively. For user of less common activities for some tasks, personal cognitive characteristics have been identified. This study could help in affordance-based design so that alternative affordance features are designed considering diverse user cognitive characteristics

    Kinematic aspects of trunk motion and gender effect in normal adults

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The purpose of this study was to analyze kinematic trunk motion data in normal adults and to investigate gender effect.</p> <p>Methods</p> <p>Kinematic trunk motion data were obtained for 20 healthy subjects (11 men and 9 women; age from 21 to 40 years) during walking a 9 m long lane at a self selected speed, namely, motions in the sagittal (tilt), coronal (obliquity), and transverse (rotation) planes, which were all expressed as motions in global (relative to the ground) and those in pelvic reference frame (relative to pelvis), i.e., tilt (G), obliquity (G), rotation (G), tilt (P), obliquity (P), rotation (P).</p> <p>Results</p> <p>Range of tilt (G), obliquity (G) and rotation (G) showed smaller motion than that of tilt (P), obliquity (P) and rotation (P), respectively. When genders were compared, female trunks showed a 5 degree more extended posture during gait than male trunks (p = 0.002), which appeared to be caused by different lumbar lordosis. Ranges of coronal and transverse plane motion appeared to be correlated. In gait cycle, the trunk motion appeared to counterbalance the lower extremity during swing phase in sagittal plane, and to reduce the angular velocity toward the contralateral side immediate before the contralateral heel strike in the coronal plane.</p> <p>Conclusions</p> <p>Men and women showed different lumbar lordosis during normal gait, which might be partly responsible for the different prevalence of lumbar diseases between genders. However, this needs further investigation.</p

    Meteorin regulates mesendoderm development by enhancing nodal expression

    Get PDF
    During gastrulation, distinct lineage specification into three germ layers, the mesoderm, endoderm and ectoderm, occurs through an elaborate harmony between signaling molecules along the embryonic proximo-distal and anterior-posterior axes, and Nodal signaling plays a key role in the early embryonic development governing embryonic axis formation, mesoderm and endoderm specification, and left-right asymmetry determination. However, the mechanism by which Nodal expression is regulated is largely unknown. Here, we show that Meteorin regulates Nodal expression and is required for mesendoderm development. It is highly expressed in the inner cell mass of blastocysts and further in the epiblast and extra-embryonic ectoderm during gastrulation. Genetic ablation of the Meteorin gene resulted in early embryonic lethality, presumably due to impaired lineage allocation and subsequent cell accumulation. Embryoid body culture using Meteorin-null embryonic stem (ES) cells showed reduced Nodal expression and concomitant impairment of mesendoderm specification. Meteorin-null embryos displayed reduced levels of Nodal transcripts before the gastrulation stage, and impaired expression of Goosecoid, a definitive endoderm marker, during gastrulation, while the proximo-distal and anterior-posterior axes and primitive streak formation were preserved. Our results show that Meteorin is a novel regulator of Nodal transcription and is required to maintain sufficient Nodal levels for endoderm formation, thereby providing new insights in the regulation of mesendoderm allocation.open1113sciescopu

    Validity of gait parameters for hip flexor contracture in patients with cerebral palsy

    Get PDF
    Background: Psoas contracture is known to cause abnormal hip motion in patients with cerebral palsy. The authors investigated the clinical relevance of hip kinematic and kinetic parameters, and 3D modeled psoas length in terms of discriminant validty, convergent validity, and responsiveness. Methods: Twenty-four patients with cerebral palsy (mean age 6.9 years) and 28 normal children (mean age 7.6 years) were included. Kinematic and kinetic data were obtained by three dimensional gait analysis, and psoas lengths were determined using a musculoskeletal modeling technique. Validity of the hip parameters were evaluated. Results: In discriminant validity, maximum psoas length (effect size r = 0.740), maximum pelvic tilt (0.710), maximum hip flexion in late swing (0.728), maximum hip extension in stance (0.743), and hip flexor index (0.792) showed favorable discriminant ability between the normal controls and the patients. In convergent validity, maximum psoas length was not significantly correlated with maximum hip extension in stance in control group whereas it was correlated with maximum hip extension in stance (r = -0.933, p &lt; 0.001) in the patients group. In responsiveness, maximum pelvic tilt (p = 0.008), maximum hip extension in stance (p = 0.001), maximum psoas length (p &lt; 0.001), and hip flexor index (p &lt; 0.001) showed significant improvement post-operatively. Conclusions: Maximum pelvic tilt, maximum psoas length, hip flexor index, and maximum hip extension in stance were found to be clinically relevant parameters in evaluating hip flexor contracture.Y

    Mind Bomb 1-Expressing Intermediate Progenitors Generate Notch Signaling to Maintain Radial Glial Cells

    Get PDF
    SummaryNotch signaling is critical for the stemness of radial glial cells (RGCs) during embryonic neurogenesis. Although Notch-signal-receiving events in RGCs have been well characterized, the signal-sending mechanism by the adjacent cells is poorly understood. Here, we report that conditional inactivation of mind bomb-1 (mib1), an essential component for Notch ligand endocytosis, in mice using the nestin and hGFAP promoters resulted in complete loss of Notch activation, which leads to depletion of RGCs, and premature differentiation into intermediate progenitors (IPs) and finally neurons, which were reverted by the introduction of active Notch1. Interestingly, Mib1 expression is restricted in the migrating IPs and newborn neurons, but not in RGCs. Moreover, sorted Mib1+ IPs and neurons can send the Notch signal to neighboring cells. Our results reveal that not only newborn neurons but also IPs are essential Notch-ligand-presenting cells for maintaining RGC stemness during both symmetric and asymmetric divisions

    Relationship between the Korean Version of the Sniffin' Stick Test and the T&T Olfactometer in the Korean Population

    Get PDF
    ObjectivesThe Korean version of the Sniffin' stick (KVSS) test is widely used in Korea to evaluate olfactory function. However, its validity and reliability have not been studied well. In this study, the authors administered the KVSS and the T%T olfactometer test to evaluate olfactory function and to establish relationships between these two test measures.MethodsTwo hundred and eleven patients participated in this prospective randomized study. One hundred and nine patients with no olfactory symptoms and 102 patients with decreased olfaction participated. All participants were underwent KVSS II and T&T olfactometer testing.ResultsThe mean recognition threshold of the T&T olfactometer was -1.8±0.9 for patients with normal olfaction and 4.0±2.6 for patients with decreased olfaction. The mean Threshold-Discrimination-Identification score of the KVSS II was 30.0±3.8 for patients with normal olfaction and 15.9±7.1 for patients with decreased olfaction. Correlation coefficient between the two tests was significantly high (rs=-0.725, P<0.01).ConclusionThe KVSS and T&T olfactometry test are both reliable tests of olfactory function and their results are well correlated with each other

    Case Reports of Adipose-derived Stem Cell Therapy for Nasal Skin Necrosis after Filler Injection

    Get PDF
    With the gradual increase of cases using fillers, cases of patients treated by non-medical professionals or inexperienced physicians resulting in complications are also increasing. We herein report 2 patients who experienced acute complications after receiving filler injections and were successfully treated with adipose-derived stem cell (ADSCs) therapy. Case 1 was a 23-year-old female patient who received a filler (Restylane) injection in her forehead, glabella, and nose by a non-medical professional. The day after her injection, inflammation was observed with a 3×3 cm skin necrosis. Case 2 was a 30-year-old woman who received a filler injection of hyaluronic acid gel (Juvederm) on her nasal dorsum and tip at a private clinic. She developed erythema and swelling in the filler-injected area A solution containing ADSCs harvested from each patient's abdominal subcutaneous tissue was injected into the lesion at the subcutaneous and dermis levels. The wounds healed without additional treatment. With continuous follow-up, both patients experienced only fine linear scars 6 months postoperatively. By using adipose-derived stem cells, we successfully treated the acute complications of skin necrosis after the filler injection, resulting in much less scarring, and more satisfactory results were achieved not only in wound healing, but also in esthetics
    corecore