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1.
J Am Chem Soc ; 146(17): 12040-12052, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38554283

RESUMEN

This study demonstrates the crucial role of reduction kinetics in phase-controlled synthesis of noble-metal nanocrystals using Ru nanocrystals as a case study. We found that the reduction kinetics played a more important role than the templating effect from the preformed seed in dictating the crystal structure of the deposited overlayers despite their intertwined effects on successful epitaxial growth. By employing two different polyols, a series of Ru nanocrystals with tunable sizes of 3-7 nm and distinct patterns of crystal phase were synthesized by incorporating different types of Ru seeds. Notably, the use of ethylene glycol and triethylene glycol consistently resulted in the formation of Ru shell in natural hexagonal close-packed (hcp) and metastable face-centered cubic (fcc) phases, respectively, regardless of the size and phase of the seed. Quantitative measurements and theoretical calculations suggested that this trend was a manifestation of the different reduction kinetics associated with the precursor and the chosen polyol, which, in turn, affected the reduction pathway (solution versus surface) and packing sequence of the deposited Ru atoms. This work not only underscores the essential role of reduction kinetics in controlling the packing of atoms and thus the phase taken by Ru nanocrystals but also suggests a potential extension to other noble-metal systems.

2.
Chaos ; 34(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38829789

RESUMEN

This paper reports an important conclusion that self-diffusion is not a necessary condition for inducing Turing patterns, while taxis could establish complex pattern phenomena. We investigate pattern formation in a zooplankton-phytoplankton model incorporating phytoplankton-taxis, where phytoplankton-taxis describes the zooplankton that tends to move toward the high-densities region of the phytoplankton population. By using the phytoplankton-taxis sensitivity coefficient as the Turing instability threshold, one shows that the model exhibits Turing instability only when repulsive phytoplankton-taxis is added into the system, while the attractive-type phytoplankton-taxis cannot induce Turing instability of the system. In addition, the system does not exhibit Turing instability when the phytoplankton-taxis disappears. Numerically, we display the complex patterns in 1D, 2D domains and on spherical and zebra surfaces, respectively. In summary, our results indicate that the phytoplankton-taxis plays a pivotal role in giving rise to the Turing pattern formation of the model. Additionally, these theoretical and numerical results contribute to our understanding of the complex interaction dynamics between zooplankton and phytoplankton populations.


Asunto(s)
Modelos Biológicos , Fitoplancton , Zooplancton , Animales , Zooplancton/fisiología , Fitoplancton/fisiología , Simulación por Computador , Dinámicas no Lineales , Ecosistema , Plancton/fisiología , Dinámica Poblacional
3.
Anal Chem ; 94(8): 3535-3542, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35061345

RESUMEN

With the growth of drug-facilitated crimes, prevention has become increasingly important. Although various drug detection technologies exist, most focus on postconsumption detection. However, the prevention of drug-facilitated crimes requires technology for the quick and easy detection of amphetamine-type stimulants (ATSs) before ingestion. Herein, drug screening kits (DSKs) were developed for the simple detection of ATSs in drinks. The DSKs consisted of polydiacetylene nanofiber-based paper sensors fabricated by electrospinning with 10,12-pentacosadiynoic acid (PCDA) and PCDA-dopamine as sensing materials that can bind ATSs via hydrogen bonding and π-π interactions. Dropping a drink on the DSK provided an immediate visual indication of the presence of ATSs. When ATSs were present in the drink, the color of the DSK clearly changed from blue to red, with the increase in red intensity being more than twofold greater than that observed when water alone was tested. Notably, the result could be confirmed by the naked eye without any analytical instrumentation. A color change indicating the presence of ATSs was successfully observed in various alcoholic and nonalcoholic drinks. These results indicate the potential of DSKs for preventing drug-facilitated crimes caused by unwanted drug intake.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Nanofibras , Anfetamina , Colorimetría/métodos
4.
Faraday Discuss ; 235(0): 273-288, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35389400

RESUMEN

We use first-principles density functional theory (DFT) to quantify the role of iodide in the solution-phase growth of Cu microplates. Our calculations show that a Cu adatom binds more strongly to hcp hollow sites than fcc hollow sites on iodine-covered Cu(111) - the basal facet of two-dimensional (2D) Cu plates. This feature promotes the formation of stacking faults during seed and plate which, in turn, promotes 2D growth. We also found that iodine adsorption leads to strong Cu atom binding and prohibitively slow diffusion of Cu atoms on Cu(100) - a feature that promotes Cu atom accumulation on the {100} site facets of a growing 2D plate. Incorporating these insights into analog experiments, in which we initiated the growth of Cu plates from small seeds consisting of magnetic spheres, we confirmed that two or more stacking faults are required for lateral plate growth, consistent with prior studies. Moreover, plates can take on a variety of shapes during growth: from triangular and truncated triangular to round and hexagonal - consistent with experiment. Using absorbing Markov chain calculations, we assessed the propensity for 2D vs. 3D kinetic growth of the plates. At experimental temperatures, we predict plates can grow to achieve lateral dimensions in the 1-10 micron range, as observed in experiments.


Asunto(s)
Yoduros , Yodo , Adsorción , Difusión , Cinética
5.
EMBO Rep ; 21(11): e49416, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-33030802

RESUMEN

Prominin-1 (Prom1) is a major cell surface marker of cancer stem cells, but its physiological functions in the liver have not been elucidated. We analyzed the levels of mRNA transcripts in serum-starved primary WT (Prom1+/+ ) and KO (Prom1-/- ) mouse hepatocytes using RNA sequencing (RNA-seq) data, and found that CREB target genes were downregulated. This initial observation led us to determine that Prom1 deficiency inhibited cAMP response element-binding protein (CREB) activation and gluconeogenesis, but not cyclic AMP (cAMP) accumulation, in glucagon-, epinephrine-, or forskolin-treated liver tissues and primary hepatocytes, and mitigated glucagon-induced hyperglycemia. Because Prom1 interacted with radixin, Prom1 deficiency prevented radixin from localizing to the plasma membrane. Moreover, systemic adenoviral knockdown of radixin inhibited CREB activation and gluconeogenesis in glucagon-treated liver tissues and primary hepatocytes, and mitigated glucagon-elicited hyperglycemia. Based on these results, we conclude that Prom1 regulates hepatic PKA signaling via radixin functioning as an A kinase-anchored protein (AKAP).


Asunto(s)
Gluconeogénesis , Glucosa , Antígeno AC133/genética , Antígeno AC133/metabolismo , Animales , Proteínas del Citoesqueleto , Gluconeogénesis/genética , Glucosa/metabolismo , Hepatocitos , Hígado/metabolismo , Proteínas de la Membrana , Ratones
6.
J Neurophysiol ; 125(3): 938-956, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33567968

RESUMEN

Magnetoencephalography (MEG) is a technique used to measure the magnetic fields generated from neuronal activity in the brain. MEG has a high temporal resolution on the order of milliseconds and provides a more direct measure of brain activity when compared with hemodynamic-based neuroimaging methods such as magnetic resonance imaging and positron emission tomography. The current review focuses on basic features of MEG such as the instrumentation and the physics that are integral to the signals that can be measured, and the principles of source localization techniques, particularly the physics of beamforming and the techniques that are used to localize the signal of interest. In addition, we review several metrics that can be used to assess functional coupling in MEG and describe the advantages and disadvantages of each approach. Lastly, we discuss the current and future applications of MEG.


Asunto(s)
Potenciales de Acción/fisiología , Fenómenos Biofísicos/fisiología , Encéfalo/fisiología , Magnetoencefalografía/métodos , Neurociencias/métodos , Animales , Humanos , Magnetoencefalografía/tendencias , Neurociencias/tendencias , Física/métodos , Física/tendencias
7.
Hum Brain Mapp ; 42(3): 598-614, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33068500

RESUMEN

Neural dynamics can shape human experience, including pain. Pain has been linked to dynamic functional connectivity within and across brain regions of the dynamic pain connectome (consisting of the ascending nociceptive pathway (Asc), descending antinociceptive pathway (Desc), salience network (SN), and the default mode network (DMN)), and also shows sex differences. These linkages are based on fMRI-derived slow hemodynamics. Here, we utilized the fine temporal resolution of magnetoencephalography (MEG) to measure resting state functional coupling (FCp) related to individual pain perception and pain interference in 50 healthy individuals (26 women, 24 men). We found that pain sensitivity and pain interference were linked to within- and cross-network broadband FCp across the Asc and SN. We also identified sex differences in these relationships: (a) women exhibited greater within-network static FCp, whereas men had greater dynamic FCp within the dynamic pain connectome; (b) relationship between pain sensitivity and pain interference with FCp in women was commonly found in theta, whereas in men, these relationships were predominantly in the beta and low gamma bands. These findings indicate that dynamic interactions of brain networks underlying pain involve fast brain communication in men but slower communication in women.


Asunto(s)
Corteza Cerebral/fisiología , Conectoma , Red en Modo Predeterminado/fisiología , Magnetoencefalografía , Red Nerviosa/fisiología , Percepción del Dolor/fisiología , Umbral del Dolor/fisiología , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Red en Modo Predeterminado/diagnóstico por imagen , Estimulación Eléctrica , Femenino , Humanos , Masculino , Red Nerviosa/diagnóstico por imagen , Caracteres Sexuales , Adulto Joven
8.
Chaos Solitons Fractals ; 136: 109896, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32421108

RESUMEN

In this study, we explored the impact of COVID-19 on the cross-correlations between crude oil and agricultural futures markets. A multifractal detrended cross-correlation analysis (MF-DCCA) approach was utilized to analyze the cross-correlations between the Brent crude oil and agricultural futures such as London Sugar, London Wheat, USA Cotton #2, and USA Orange Juice futures. We initially confirmed their correlations by calculating the DCCA coefficient. Then, from the multifractal aspect, the cross-correlations were further explored, and the sources for forming the correlations were discussed. The results show that the Brent Crude Oil has the strongest cross-correlation with London Sugar Future market among other three agricultural future markets. Then we investigated the influence of COVID-19 on the cross-correlations of multifractality between crude oil and agricultural futures. The experimental results indicated that the persistence under the influence of COVID-19 became stronger, and the cross-correlations of multifractality between crude oil and sugar future market is the strongest. In addition, the cross-correlations of all the agricultural futures increased after the emergence of COVID-19 except the orange juice future market. In general, COVID-19 has a great impact on the cross-correlation of multifractal property between crude oil and most selected agricultural future markets.

9.
Chaos Solitons Fractals ; 139: 110090, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32834625

RESUMEN

In this article, we propose the Susceptible-Unidentified infected-Confirmed (SUC) epidemic model for estimating the unidentified infected population for coronavirus disease 2019 (COVID-19) in China. The unidentified infected population means the infected but not identified people. They are not yet hospitalized and still can spread the disease to the susceptible. To estimate the unidentified infected population, we find the optimal model parameters which best fit the confirmed case data in the least-squares sense. Here, we use the time series data of the confirmed cases in China reported by World Health Organization. In addition, we perform the practical identifiability analysis of the proposed model using the Monte Carlo simulation. The proposed model is simple but potentially useful in estimating the unidentified infected population to monitor the effectiveness of interventions and to prepare the quantity of protective masks or COVID-19 diagnostic kit to supply, hospital beds, medical staffs, and so on. Therefore, to control the spread of the infectious disease, it is essential to estimate the number of the unidentified infected population. The proposed SUC model can be used as a basic building block mathematical equation for estimating unidentified infected population.

10.
J Neurosci ; 38(33): 7293-7302, 2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-30012686

RESUMEN

Measures of moment-to-moment fluctuations in brain activity of an individual at rest have been shown to be a sensitive and reliable metric for studying pathological brain mechanisms across various chronic pain patient populations. However, the relationship between pathological brain activity and clinical symptoms are not well defined. Therefore, we used regional BOLD signal variability/amplitude of low-frequency oscillations (LFOs) to identify functional brain abnormalities in the dynamic pain connectome in chronic pain patients that are related to chronic pain characteristics (i.e., pain intensity). Moreover, we examined whether there were sex-specific attributes of these functional brain abnormalities and whether functional brain abnormalities in patients is related to pain intensity characteristics on different time scales. We acquired resting-state functional MRI and quantified frequency-specific regional LFOs in chronic pain patients with ankylosing spondylitis. We found that patients exhibit frequency-specific aberrations in LFOs. Specifically, lower-frequency (slow-5) abnormalities were restricted to the ascending pain pathway (thalamus and S1), whereas higher-frequency abnormalities also included the default mode (i.e., posterior cingulate cortex; slow-3, slow-4) and salience (i.e., mid-cingulate cortex) networks (slow-4). Using a machine learning approach, we found that these abnormalities, in particular within higher frequencies (slow-3), can be used to make generalizable inferences about patients' average pain ratings (trait-like pain) but not current (i.e., state-like) pain levels. Furthermore, we identified sex differences in LFOs in patients that were not present in healthy controls. These novel findings reveal mechanistic brain abnormalities underlying the longer-lasting symptoms (trait pain intensity) in chronic pain.SIGNIFICANCE STATEMENT Measures of moment-to-moment fluctuations in brain activity of an individual at rest have been shown to be a reliable metric for studying functional brain associated with chronic pain. The current results demonstrate that dysfunction in these intrinsic fluctuations/oscillations in the ascending pain pathway, default mode network, and salience network during resting state display sex differences and can be used to make inferences about trait-like pain intensity ratings in chronic pain patients. These results provide robust and generalizable implications for investigating brain mechanisms associated with longer-lasting/trait-like chronic pain symptoms.


Asunto(s)
Relojes Biológicos/fisiología , Mapeo Encefálico , Dolor Crónico/fisiopatología , Conectoma , Neuroimagen Funcional , Aprendizaje Automático , Adolescente , Adulto , Dolor Crónico/etiología , Femenino , Giro del Cíngulo/fisiología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Descanso , Caracteres Sexuales , Corteza Somatosensorial/fisiología , Espondilitis Anquilosante/complicaciones , Tálamo/fisiología , Adulto Joven
11.
J Sport Rehabil ; 28(3): 272-277, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30040007

RESUMEN

CONTEXT: A winged scapula (WS) is associated with faulty posture caused by weakness of the serratus anterior (SA), which mainly acts as a scapular stabilizer muscle. It is important to accurately assess and train the SA muscle with a focus on scapula stabilizers during musculoskeletal rehabilitation of individuals with a WS. OBJECTIVE: The authors examined muscle activity in the SA and pectoralis major (PM), upper trapezius (UT), and anterior deltoid (AD) as well as shoulder protraction strength during isometric shoulder protraction in individuals with and without a WS. DESIGN: Cross-sectional study. SETTING: A clinical biomechanics laboratory. PARTICIPANTS: In total, 27 males with no shoulder, neck, or upper-extremity pain participated. MAIN OUTCOME MEASURES: Isometric shoulder protraction strength was collected and surface electromyography used to measure the activity of the SA, PM, UT, and AD muscles and selective SA activity ratio to other shoulder muscles. RESULTS: Electromyography activity of the SA muscle and shoulder protraction strength were significantly lower in individuals with a WS compared with the non-WS group (P < .05). In contrast, PM muscle activity and the PM-to-SA, UT-to-SA, and AD-to-SA ratios were significantly greater in individuals with a WS than in individuals without winging (P < .05). CONCLUSIONS: Isometric shoulder protraction for measuring SA strength in individuals with a WS should focus on isolated muscle activity of the SA, and SA strengthening exercises are important for individuals with a WS.


Asunto(s)
Fuerza Muscular , Músculos Pectorales/fisiología , Escápula/anatomía & histología , Hombro/fisiología , Músculos Superficiales de la Espalda/fisiología , Adulto , Estudios Transversales , Electromiografía , Humanos , Contracción Isométrica , Masculino , Postura , Adulto Joven
12.
Anesthesiology ; 129(5): 1015-1024, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30199420

RESUMEN

WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Ketamine is an N-methyl-D-aspartate receptor antagonist that reduces temporal summation of pain and modulates antinociception. Ketamine infusions can produce significant relief of neuropathic pain, but the treatment is resource intensive and can be associated with adverse effects. Thus, it is crucial to select patients who might benefit from this treatment. The authors tested the hypothesis that patients with enhanced temporal summation of pain and the capacity to modulate pain via the descending antinociceptive brain pathway are predisposed to obtain pain relief from ketamine. METHODS: Patients with refractory neuropathic pain (n = 30) and healthy controls underwent quantitative sensory testing and resting-state functional magnetic resonance imaging and then completed validated questionnaires. Patients then received outpatient intravenous ketamine (0.5 to 2 mg · kg · h; mean dose 1.1 mg · kg · h) for 6 h/day for 5 consecutive days. Pain was assessed 1 month later. Treatment response was defined as greater than or equal to 30% pain relief (i.e., reduction in pain scores). We determined the relationship between our primary outcome measure of pain relief with pretreatment temporal summation of pain and with brain imaging measures of dynamic functional connectivity between the default mode network and the descending antinociceptive brain pathway. RESULTS: Approximately 50% of patients achieved pain relief (mean ± SD; Responders, 61 ± 35%; Nonresponders, 7 ± 14%). Pretreatment temporal summation was associated with the effect of ketamine (ρ = -0.52, P = 0.003) and was significantly higher in Responders (median [25th, 75th] = 200 [100, 345]) compared with Nonresponders (44 [9, 92]; P = 0.001). Pretreatment dynamic connectivity was also associated with the clinical effect of ketamine (ρ = 0.51, P = 0.004) and was significantly higher in Responders (mean ± SD, 0.55 ± 0.05) compared with Nonresponders (0.51 ± 0.03; P = 0.006). Finally, the dynamic engagement of the descending antinociceptive system significantly mediated the relationship between pretreatment pain facilitation and pain relief (95% CI, 0.005 to 0.065). CONCLUSIONS: These findings suggest that brain and behavioral measures have the potential to prognosticate and develop ketamine-based personalized pain therapy.


Asunto(s)
Analgésicos/uso terapéutico , Encéfalo/fisiopatología , Ketamina/uso terapéutico , Neuralgia/tratamiento farmacológico , Dimensión del Dolor/métodos , Adulto , Analgésicos/administración & dosificación , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Infusiones Intravenosas , Ketamina/administración & dosificación , Imagen por Resonancia Magnética , Masculino , Neuralgia/fisiopatología , Dolor/fisiopatología , Encuestas y Cuestionarios , Tiempo , Resultado del Tratamiento
13.
J Magn Reson Imaging ; 43(5): 1191-5, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26435493

RESUMEN

PURPOSE: To evaluate the reproducibility of cerebrovascular reactivity (CVR) measurements acquired in children using magnetic resonance imaging (MRI) in combination with a computer-controlled carbon dioxide (CO2 ) stimulus. MATERIALS AND METHODS: Ten healthy children (age 16.1 ± 1.6 years) underwent CVR imaging on a 3T scanner using a blood-oxygen level-dependent (BOLD) MRI sequence. Targeted hypercapnia was induced during imaging with a CO2 gas challenge delivered using a specialized gas sequencer (RespirAct). A total of four BOLD scans were performed over 2 separate days to test within-day and between-day consistency of the data. CVR values were computed by correlating the relative change in BOLD signal in response to the CO2 stimulus delivered to the each subject. RESULTS: Intraclass correlation coefficients (ICCs) of within-day values show highly reproducible measures in both the gray matter (ICC = 0.857, P < 0.001) and white matter (ICC = 0.895, P < 0.001). Relatively lower between-day reproducibility was observed in both the gray matter (ICC = 0.776, P = 0.001) and white matter (ICC = 0.719, P = 0.004). CONCLUSION: Using a computer-controlled CO2 stimulus, we have demonstrated the reliability of BOLD-CVR measurements in pediatric subjects. Within-day and between-day metrics of reproducibility were comparable to adult data.


Asunto(s)
Dióxido de Carbono/química , Circulación Cerebrovascular , Imagen por Resonancia Magnética , Adolescente , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Computadores , Femenino , Homeostasis , Humanos , Hipercapnia/diagnóstico por imagen , Masculino , Movimiento (Física) , Reproducibilidad de los Resultados
14.
Physica A ; 451: 190-197, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32288098

RESUMEN

In this paper, we propose the daily computed weighted averaging basic reproduction number R 0 , k , ω n for Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak in South Korea, May to July 2015. We use an SIR model with piecewise constant parameters ß (contact rate) and γ (removed rate). We use the explicit Euler's method for the solution of the SIR model and a nonlinear least-square fitting procedure for finding the best parameters. In R 0 , k , ω n , the parameters n , k , and w denote days from a reference date, the number of days in averaging, and a weighting factor, respectively. We perform a series of numerical experiments and compare the results with the real-world data. In particular, using the predicted reproduction number based on the previous two consecutive reproduction numbers, we can predict the future behavior of the reproduction number.

15.
Eur Phys J E Soft Matter ; 38(11): 117, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26577816

RESUMEN

We investigate microphase separation patterns on curved surfaces in three-dimensional space by numerically solving a nonlocal Cahn-Hilliard equation for diblock copolymers. In our model, a curved surface is implicitly represented as the zero level set of a signed distance function. We employ a discrete narrow band grid that neighbors the curved surface. Using the closest point method, we apply a pseudo-Neumann boundary at the boundary of the computational domain. The boundary treatment allows us to replace the Laplace-Beltrami operator by the standard Laplacian operator. In particular, we can apply standard finite difference schemes in order to approximate the nonlocal Cahn-Hilliard equation in the discrete narrow band domain. We employ a type of unconditionally stable scheme, which was introduced by Eyre, and use the Jacobi iterative to solve the resulting implicit discrete system of equations. In addition, we use the minimum number of grid points for the discrete narrow band domain. Therefore, the algorithm is simple and fast. Numerous computational experiments are provided to study microphase separation patterns for diblock copolymers on curved surfaces in three-dimensional space.

16.
J Phys Ther Sci ; 27(8): 2507-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26357430

RESUMEN

[Purpose] This study evaluated the effect of smartphone use on lumbar spine repositioning error and lumbar curvature while walking on a treadmill. [Subjects] A total of 20 healthy individuals (18 males and 2 females) volunteered for this study. [Methods] The subjects walked for 20 min on a treadmill while using a smartphone. To determine the effect of smartphone use, lumbar repositioning error was measured using an electronic goniometer while lumbar curvature was assessed using a Spinal Mouse before and immediately after treadmill use. Differences in the lumbar repositioning error and lumbar curvature data between the pre- and post-walking were compared using the paired t-test. [Results] The lumbar spine repositioning error was significantly greater post-walking compared with pre-walking (6.70±2.91° vs. 3.02±1.79°). There was no significant difference in lumbar curvature between pre- and post-walking (14.24±3.18° vs. 13.94±3.12°). [Conclusion] These findings indicate that the lumbar repositioning error increased immediately after walking while using a smartphone, but that the lumbar curvature was unchanged.

17.
J Phys Ther Sci ; 27(4): 1037-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25995550

RESUMEN

[Purpose] This study examined the selective electromyographic activity of the lumbar paraspinal muscles in healthy male and female subjects in the prone trunk extension (PTE) and four-point kneeling arm and leg lift (FPKAL) exercises to determine the most beneficial exercise for selective activation of the lumbar multifidus (LM). [Subjects and Methods] Twenty healthy male and female subjects participated in this study. Surface electromyographic data were collected from the left-side lumbar erector spinae (LES) and LM muscles during PTE and FPKAL exercises. [Results] The LM/LES ratio related to selective activation of the lumbar paraspinal muscles during the FPKAL exercise was higher than that during PTE. [Conclusion] FPKAL exercise is safe and effective for the selective activation of the LM muscle.

18.
J Phys Ther Sci ; 27(1): 247-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25642084

RESUMEN

[Purpose] The purpose of this study was to compare the EMG activity of the tibialis anterior (TA) and gastrocnemius (GCM) during the downward, maintenance, and upward phases of the squat exercise and during passive ankle dorsiflexion range of motion between stroke patients and healthy subjects. [Subjects] Fifteen hemiplegic (8 males, 7 females) and 15 healthy subjects (4 males, 11 females) volunteered for this study. [Methods] All subjects performed a double-leg squat exercise with the knee joint flexed to 30°. Surface electromyography (EMG) signals were recorded from the TA and GCM on the paretic or nondominant side. Passive ankle dorsiflexion range of motion (DF PROM) was measured using a goniometer in the knee-extended prone position. [Results] In the downward and maintenance phases, TA activity was significantly higher in stroke patients compared with healthy subjects. In the upward phase, GCM activity was significantly lower in stroke patients compared with healthy subjects. Ankle DF PROM was significantly lower in stroke patients compared with healthy subjects. [Conclusion] The observed EMG patterns should be taken into consideration to inform and enhance therapy for stroke patients.

19.
J Phys Ther Sci ; 27(5): 1317-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26157209

RESUMEN

[Purpose] The purpose of this study was to investigate the effect of gastrocnemius stretching combined with talocrural joint mobilization on weight-bearing ankle dorsiflexion passive range of motion. [Subjects] Eleven male subjects with bilateral limited ankle dorsiflexion passive range of motion with knee extended participated in this study. [Methods] All subjects received talocrural joint mobilization while performing gastrocnemius stretching. Ankle dorsiflexion passive range of motion was measured using an inclinometer under weight-bearing conditions before and immediately after intervention. A paired t-test was used to analyze the difference between weight-bearing ankle dorsiflexion passive range of motion pre- and post-intervention. [Results] A significant increase in weight-bearing ankle dorsiflexion passive range of motion was found post-intervention compared with pre-intervention. [Conclusion] These findings demonstrate that gastrocnemius stretching combined with joint mobilization is effective for increasing weight-bearing ankle dorsiflexion passive range of motion.

20.
J Nanosci Nanotechnol ; 14(2): 1303-17, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24749427

RESUMEN

Roll-to-roll (R2R) gravure is considered one of the highest throughput tools for manufacturing inexpensive and flexible ubiquitous IT devices called "smart packaging" in which NFC (near-field communication) transponder, sensors, ADC (analog-to-digital converter), simple processor and signage are all integrated on paper or plastic foils. In this review, we show R2R gravure can be employed to print smart packaging, starting from printing simple electrodes, dielectrics, capacitors, diodes and thin film transistors with appropriate nanomaterial-based inks on plastic foils.


Asunto(s)
Electrónica/instrumentación , Membranas Artificiales , Nanoestructuras/química , Plásticos/química , Etiquetado de Productos/instrumentación , Embalaje de Productos/instrumentación , Dispositivo de Identificación por Radiofrecuencia , Conductividad Eléctrica , Diseño de Equipo , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Etiquetado de Productos/métodos , Embalaje de Productos/métodos
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