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1.
J Biomed Phys Eng ; 11(1): 9-16, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33564635

RESUMEN

BACKGROUND: Head and neck cancers are currently the most common types of cancers. 3D-conformal radiation therapy is the most common dose delivery technique for head and neck cancers. Eye Lens is a radio sensitive structure and cataract formation as a visual disorder associated with exposure to ionizing radiation which is documented. OBJECTIVE: Determining the radiation dose to eye lens during head and neck radiography and estimating the probability of cataract induction are essential. MATERIAL AND METHODS: This experimental study was performed on 14 patients with head and neck cancers through experimental study analysis. The maximum opacity of the eyes lens were measured by pentacamTM before radiation therapy. CT data of patients were transmitted to Isogray treatment planning Software, and dose calculations for each patient was performed. At the end of radiation treatment, 3 and 6 months after radiotherapy, the eye lens opacity of the patients was assessed. RESULTS: Overall, 28 lenses were studied. Statistical one sample K- S test proved normality of obtained data. Using repeated measures test, the relation before and 3 months after radiotherapy, as well as the relationship before and 6 months after radiotherapy proved a significant relationship. CONCLUSION: The opacity caused by radiation in eyes is a non-statistical and linear-quadratic response curve with no threshold. This opacity can also appear within 3 months after completion of radiation therapy.

2.
J Educ Health Promot ; 7: 31, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29629392

RESUMEN

AIM AND BACKGROUND: Mental health and empowerment are two of the women's essential needs. These two related concepts play an important role in women's lives. Therefore, this study aimed to investigate empowerment of women and its relation with mental health problem prevention during difficult situations. METHODS: This qualitative study was conducted through semi-structured interviews with 33 experts in the fields of psychology, social sciences, women studies, medicine and crisis management specialists using snowball sampling in cities of Tehran, Isfahan, Tabriz, and Mashhad during the year 1395 (March 2016-March 2017). Samples were selected heterogeneously. The interview transcripts and codes were presented to the participants, and structural analysis was used for data evaluation. RESULTS: The factors related to empowerment of women with consideration to their mental health were determined based on Longew theory and interviews and include: welfare (primary needs (biological and security) and developmental needs (social needs and dignity), access (facilities and values), knowledge (about inequalities and rights), participation (in politics, decision-making and society), and control (implementation and institutionalization of the above-mentioned needs). CONCLUSIONS: The indicators determined in this study show that empowerment has an important role in determining women's real position in society. Since women make up half of the population and affect society as a whole, the advantages of empowerment of women will be felt in the entire society.

3.
Bratisl Lek Listy ; 119(11): 684-691, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30686001

RESUMEN

The purpose of this experimental study is evaluation of the effect of BMSCs Condition Media and Methylprednisolone in TGF-ß expression and functional recovery after acute spinal cord injury in adult wistar rat. MATERIAL AND METHODS: After an acute spinal cord injury, MP and BMSC-CM were injected intraperitoneally and the recovery rate was evaluated by BBB and narrow beam test. Real time PCR, H[et]E staining, cavity formation and stereology was done after 12 weeks post injury. RESULT: There were significant differences in functional recovery between MP+CM group, relative to other groups. TGF-ß1 expression decreased in MP+CM group compared to the control group. Cavity size in experimental groups decreased compared to the control group. The mean volume of spinal cord demonstrated a significant increase in the MP+CM group in comparison to the other experimental groups. CONCLUSION: Simultaneous use of MP and BMSC-CM will improve recovery from the spinal cord injury, reduce inflammation and improve functional recovery (Tab. 1, Fig. 8, Ref. 26).


Asunto(s)
Metilprednisolona , Traumatismos de la Médula Espinal , Trasplante de Células Madre , Factor de Crecimiento Transformador beta , Animales , Trasplante de Médula Ósea , Medios de Cultivo Condicionados , Metilprednisolona/uso terapéutico , Ratas , Recuperación de la Función , Médula Espinal , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/terapia , Factor de Crecimiento Transformador beta/metabolismo
4.
J Mol Graph Model ; 77: 263-279, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28903086

RESUMEN

Understanding the size-dependent behavior of structures at nanoscale is essential in order to have an effective design of nanosystems. In the current investigation, the surface elasticity theory is extended to study the nonlinear buckling and postbuckling response of axially loaded silicon cylindrical naoshells. Thereby, an efficient size-dependent shear deformable shell model is developed including the size effect of surface free energy. A boundary layer theory of shell buckling in conjunction with a perturbation-based solution methodology is employed to predict the size dependency in the buckling loads and postbuckling behavior of silicon nanoshells having various thicknesses. After that, on the basis of the Tersoff empirical potential, a molecular dynamics (MD) simulation is performed for a silicon cylindrical nanoshell with thickness of four times of silicon lattice constant, the critical buckling load and critical shortening of which are extracted and compared with those of the developed non-classical shell model. It is demonstrated that by taking the effects of surface free energy into account, a very good agreement is achieved between the results of the developed size-dependent continuum shell model and those of MD simulation.


Asunto(s)
Nanocáscaras/química , Silicio/química , Estrés Mecánico , Elasticidad , Simulación de Dinámica Molecular , Presión
5.
Opt Express ; 25(14): 16840-16853, 2017 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-28789183

RESUMEN

Using Maxwell's equations for the incoming and outgoing electromagnetic field, in interaction with a metallic arm-chair graphene nanoribbon (AGNR), and the relationship between the density-density response function and the conductivity, we study surface plasmons (SPs) in a AGNR following the Lindhard, random-phase approximation (RPA), and Hubbard approaches. For transverse magnetic (TM) modes we obtain analytical dispersion relations (DRs) valid for q ≤ kF and assess their width dependence. In all approaches we include screening. In the long-wavelength limit q → 0 there is a small but noticeable difference between the DRs of the three approaches. In this limit the respective, scattering-free conductivities differ drastically from those obtained when scattering by impurities is included. We demonstrate that the SP field is proportional to the square of the quality factor Q. The reflection amplitude shows that metallic AGNRs do not support Brewster angles. In addition, AGNRs do not support transverse electric (TE) SPs.

6.
Ultrasound Obstet Gynecol ; 49(3): 315-321, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27546354

RESUMEN

OBJECTIVE: Randomized controlled trials (RCTs) have recently compared intramuscular 17α-hydroxyprogesterone caproate (17-OHPC) with vaginal progesterone for reducing the risk of spontaneous preterm birth (SPTB) in singleton gestations with prior SPTB. The aim of this systematic review and meta-analysis was to evaluate the efficacy of vaginal progesterone compared with 17-OHPC in prevention of SPTB in singleton gestations with prior SPTB. METHODS: Searches of electronic databases were performed to identify all RCTs of asymptomatic singleton gestations with prior SPTB that were randomized to prophylactic treatment with either vaginal progesterone (intervention group) or intramuscular 17-OHPC (comparison group). No restrictions for language or geographic location were applied. The primary outcome was SPTB < 34 weeks. Secondary outcomes were SPTB < 37 weeks, < 32 weeks, < 28 weeks and < 24 weeks, maternal adverse drug reaction and neonatal outcomes. The summary measures were reported as relative risk (RR) with 95% CI. Risk of bias for each included study was assessed. RESULTS: Three RCTs (680 women) were included. The mean gestational age at randomization was about 16 weeks. Women were given progesterone until 36 weeks or delivery. Regarding vaginal progesterone, one study used 90 mg gel daily, one used 100 mg suppository daily and one used 200 mg suppository daily. All included RCTs used 250 mg intramuscular 17-OHPC weekly in the comparison group. Women who received vaginal progesterone had significantly lower rates of SPTB < 34 weeks (17.5% vs 25.0%; RR, 0.71 (95% CI, 0.53-0.95); low quality of evidence) and < 32 weeks (8.9% vs 14.5%; RR, 0.62 (95% CI, 0.40-0.94); low quality of evidence) compared with women who received 17-OHPC. There were no significant differences in the rates of SPTB < 37 weeks, < 28 weeks and < 24 weeks. The rate of women who reported adverse drug reactions was significantly lower in the vaginal progesterone group compared with the 17-OHPC group (7.1% vs 13.2%; RR, 0.53 (95% CI, 0.31-0.91); very low quality of evidence). Regarding neonatal outcomes, vaginal progesterone was associated with a lower rate of neonatal intensive care unit admission compared with 17-OHPC (18.7% vs 23.5%; RR, 0.63 (95% CI, 0.47-0.83); low quality of evidence). For the comparison of 17-OHPC vs vaginal progesterone, the quality of evidence was downgraded for all outcomes by at least one degree due to imprecision (the optimal information size was not reached) and by at least one degree due to indirectness (different interventions). CONCLUSIONS: Daily vaginal progesterone (either suppository or gel) started at about 16 weeks' gestation is a reasonable, if not better, alternative to weekly 17-OHPC injection for prevention of SPTB in women with singleton gestations and prior SPTB. However, the quality level of the summary estimates was low or very low as assessed by GRADE, indicating that the true effect may be, or is likely to be, substantially different from the estimate of the effect. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. COMPARACIÓN ENTRE LA PROGESTERONA VAGINAL Y EL 17Α-HIDROXIPROGESTERONA CAPROATO INTRAMUSCULAR PARA LA PREVENCIÓN DEL PARTO PRETÉRMINO ESPONTÁNEO RECURRENTE EN EMBARAZOS CON FETO ÚNICO: REVISIÓN SISTEMÁTICA Y METAANÁLISIS DE ENSAYOS CONTROLADOS ALEATORIOS: RESUMEN OBJETIVO: Recientemente se han realizado varios ensayos controlados aleatorios (ECA) que comparaban el caproato de 17α-hidroxiprogesterona (17-OHPC, por sus siglas en inglés) por vía intramuscular con la progesterona por vía vaginal para la reducción del riesgo de parto pretérmino espontáneo (PPTE) en embarazos con feto único de gestantes con historial de PPTE. El objetivo de esta revisión sistemática y metaanálisis fue evaluar la eficacia de la progesterona vaginal en comparación con la 17-OHPC en la prevención de embarazos con feto único de gestantes con historial de PPTE. MÉTODOS: Se realizaron búsquedas en bases de datos electrónicas para identificar todos los ECA con embarazos de feto único asintomáticos con historial de PPTE antes de ser asignados al azar a un tratamiento profiláctico, ya fuera con progesterona vaginal (grupo de intervención) o con 17-OHPC intramuscular (grupo de control). No se aplicaron restricciones respecto al idioma o la ubicación geográfica. El resultado primario fue PPTE < 34 semanas. Los resultados secundarios fueron PPTE <37 semanas, < 32 semanas, < 28 semanas y < 24 semanas, la reacción materna adversa al fármaco y los resultados neonatales. Las medidas del resumen se reportaron como riesgo relativo (RR) con IC del 95%. Para cada estudio incluido se evaluó el riesgo de sesgo. RESULTADOS: Se incluyeron tres ECA (680 mujeres). La media de la edad gestacional en el momento de la aleatorización fue de 16 semanas. A las mujeres se les administró progesterona hasta la semana 36 o hasta el parto. Con respecto a la progesterona vaginal, un estudio utilizó gel de 90 mg diariamente, otro utilizó un supositorio diario de 100 mg y el otro utilizó un supositorio diario de 200 mg. Todos los ECA incluidos en el grupo de comparación utilizaron 250 mg semanales de 17-OHPC por vía intramuscular. Las mujeres que recibieron progesterona vaginal tuvieron tasas significativamente más bajas de PPTE < 34 semanas (17,5% vs. 25,0%; RR 0,71 (IC 95%, 0,53-0,95); calidad de la evidencia baja) y < 32 semanas (8,9% vs. 14,5%; RR 0,62 (IC 95%, 0,40-0,94); calidad de evidencia baja), en comparación con las mujeres que recibieron 17-OHPC. No hubo diferencias significativas en las tasas de PPTE < 37 semanas, < 28 semanas y < 24 semanas. La tasa de mujeres que reportaron reacciones adversas a los medicamentos fue significativamente menor en el grupo de progesterona vaginal en comparación con el grupo de 17-OHPC (7,1% vs. 13,2%; RR 0,53 (IC 95%, 0,31-0,91); calidad de la evidencia muy baja). En cuanto a los resultados neonatales, la progesterona vaginal se asoció a una menor tasa de admisiones en la unidad neonatal de cuidados intensivos en comparación con la 17-OHPC (18,7% vs. 23,5%; RR 0,63 (IC 95%, 0,47-0,83); calidad de evidencia baja). Para la comparación del 17-OHPC con la progesterona vaginal se rebajó la calidad de las pruebas para todos los resultados en al menos un grado debido a imprecisiones (no se alcanzó el tamaño óptimo de la información) y en al menos un grado debido al carácter indirecto de los estudios (diferentes intervenciones). CONCLUSIONES: La progesterona vaginal administrada diariamente (ya fuera como supositorio o como gel) desde la semana 16 de gestación es una alternativa razonable, si no mejor, a una inyección semanal de 17-OHPC para la prevención de PPTE en mujeres con embarazos de feto único e historial de PPTE. Sin embargo, el nivel de calidad de las estimaciones del resumen fue bajo o muy bajo según lo evaluado por GRADE, lo que indica que el verdadero efecto puede ser, o es probable que sea, sustancialmente diferente de la estimación del efecto. 17Α-:META: : (randomized controlled trials,RCTs)(spontaneous preterm birth,SPTB)17α-(intramuscular 17α-hydroxyprogesterone caproate,17-OHPC)SPTB。metaSPTB17-OHPCSPTB。 : ,SPTBRCTs,RCTs()17-OHPC()。。34SPTB。37、32、2824SPTB,。(relative risk,RR)95%CI。。 : 3RCTs(680)。16。,36。,90 mg,100 mg,200 mg。,RCTs250 mg 17-OHPC。17-OHPC,34 [17.5%25.0%;RR,0.71(95% CI,0.53 ~ 0.95);]32[8.9%14.5%;RR,0.62(95% CI,0.40 ~ 0.94);]SPTB。37、2824SPTB。17-OHPC,[7.1%13.2%;RR,0.53(95% CI,0.31 ~ 0.91);]。,17-OHPC,[18.7%23.5%;RR,0.63(95% CI,0.47 ~ 0.83);]。17-OHPC,(),()。 : SPTBSPTB,16()17-OHPC,。,GRADE,,。.


Asunto(s)
Hidroxiprogesteronas/administración & dosificación , Nacimiento Prematuro/prevención & control , Progesterona/administración & dosificación , Caproato de 17 alfa-Hidroxiprogesterona , Administración Intravaginal , Esquema de Medicación , Femenino , Humanos , Hidroxiprogesteronas/uso terapéutico , Inyecciones Intramusculares , Unidades de Cuidados Intensivos , Admisión del Paciente/estadística & datos numéricos , Embarazo , Progesterona/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Cell Mol Biol (Noisy-le-grand) ; 62(5): 44-54, 2016 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-27188869

RESUMEN

Cutaneous wound healing is a complex type of biological event involving proliferation, differentiation, reprograming, trans/de-differentiation, recruitment, migration, and apoptosis of a number of cells (keratinocytes, fibroblasts, endothelial cells, nerve cells and stem cells) to regenerate a multi-layered tissue that is damaged by either internal or external factors. The exact regeneration mechanism of damaged skin is still unknown but the epithelial and other kinds of stem cells located in skin play crucial roles in the healing process. In this work, a co-culture model composed of adipose derived mesenchymal stem cells and keratinocytes was developed to understand the cellular differentiation behaviour in wound healing. Human mesenchymal stem cells were isolated from waste lipoaspirates. Keratinocytes were isolated from neonatal rats skin as well from human adult skin. Both types of cells were cultured and their culturing behaviour was observed microscopically under regular intervals of time. The identity of both cells was confirmed by flow cytometry and qRT-PCR. Cells were co-cultured under the proposed co-culturing model and the model was observed for 7, 14 and 21 days. The cellular behaviour was studied based on change in morphology, colonization, stratification, migration and expression of molecular markers. Expression of molecular markers was studied at transcriptional level and change in cellular morphology and migration capabilities was observed under the invert microscope regularly. Successfully isolated and characterized mesenchymal stem cells were found to express keratinocyte lineage markers i.e. K5, K10, K14, K18, K19 and Involucrin when co-cultured with keratinocytes after 14 and 21 days. Their expression was found to increase by increasing the time span of cell culturing. The keratinocyte colonies started to disappear after 10 days of culturing which might be due to stratification process initiated by possibly transdifferentiated stem cells. It can be concluded that mesenchymal stem cells can regenerate the damaged skin if transplanted to damaged area but for their successful differentiation and enhanced regeneration, they need a population of keratinocytes in situ which need further experiments for validation of co-culture model and its potential for being used in clinics.


Asunto(s)
Tejido Adiposo/citología , Biomarcadores/metabolismo , Linaje de la Célula , Técnicas de Cocultivo/métodos , Queratinocitos/citología , Células Madre Mesenquimatosas/citología , Adipocitos/citología , Animales , Animales Recién Nacidos , Diferenciación Celular , Proliferación Celular , Separación Celular , Células Cultivadas , Citometría de Flujo , Humanos , Trasplante de Células Madre Mesenquimatosas , Osteoblastos/citología , Ratas , Cicatrización de Heridas
8.
Phys Rev Lett ; 116(9): 090402, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26991158

RESUMEN

Collapse models predict a tiny violation of energy conservation, as a consequence of the spontaneous collapse of the wave function. This property allows us to set experimental bounds on their parameters. We consider an ultrasoft magnetically tipped nanocantilever cooled to millikelvin temperature. The thermal noise of the cantilever fundamental mode has been accurately estimated in the range 0.03-1 K, and any other excess noise is found to be negligible within the experimental uncertainty. From the measured data and the cantilever geometry, we estimate the upper bound on the continuous spontaneous localization collapse rate in a wide range of the correlation length r_{C}. Our upper bound improves significantly previous constraints for r_{C}>10^{-6} m, and partially excludes the enhanced collapse rate suggested by Adler. We discuss future improvements.

9.
Mater Sci Eng C Mater Biol Appl ; 48: 572-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25579959

RESUMEN

The goal of the present research was to fabricate, characterize, and evaluate mechanical and biological properties of Co-base alloy composites with different amounts of hydroxyapatite (HA) nanopowder reinforcement. The powder of Co-Cr-Mo alloy was mixed with different amounts of HA by ball milling and it was then cold pressed and sintered. X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques were used. Microhardness measurement and compressive tests were also carried out. Bioactivity behavior was evaluated in simulated body fluid (SBF). A significant decrease in modulus elasticity and an increase in microhardness of the sintered composites were observed. Apatite formation on the surface of the composites showed that it could successfully convert bioinert Co-Cr-Mo alloy to bioactive type by adding 10, 15, and 20wt.% HA which have lower modulus elasticity and higher microhardness.


Asunto(s)
Aleaciones/química , Líquidos Corporales/química , Cerámica/química , Cobalto/química , Durapatita/química , Ensayo de Materiales , Nanocompuestos/química , Módulo de Elasticidad , Nanocompuestos/ultraestructura , Tamaño de la Partícula
10.
Phys Chem Chem Phys ; 16(47): 25760-4, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25354544

RESUMEN

(PhSiO1.5)8,10,12 cages are bulky, electron withdrawing like CF3; yet self-brominate (60 °C), favoring ortho substitution: PhT8 (≈85%), PhT10 (≈75%) and PhT12 (60%). First-principles calculations suggest bromination initiates when Br2 is "trapped" via H-bonding to ortho-H's, followed by polarization via strong interactions with cage faces, possibly cage LUMOs.

11.
Appl Opt ; 53(27): 6307-16, 2014 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-25322112

RESUMEN

A metallic subwavelength grating structure built on a thin gold film is studied for surface plasmon resonance (SPR) detection of refractive index variations of biological buffer solutions. By employing finite element analysis as a numerical method, characteristics of the angle interrogated SPR sensor were calculated and discussed in a broad operating wavelength varying from visible to near-infrared (NIR). The effects of grating structural parameters such as grating depth, grating period, and grating fill factor in different operating wavelengths have been evaluated on the sensor performance parameters of sensitivity, full width at half-minimum, minimum reflectance at resonance, and resonance angle. Numerical results indicate that adjusting grating geometrical parameters can enhance the performance parameters of the sensor especially in the NIR wavelengths. The enhanced sensor performance parameters for optimizing grating geometry have been explored in detail for visible and NIR wavelengths of 633 and 984 nm, respectively. These findings are important for developing localized surface plasmon sensors with enhanced performance.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Nanotecnología/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Transductores , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Ensayo de Materiales , Nanopartículas del Metal/efectos de la radiación , Modelos Químicos , Dispersión de Radiación
12.
Top Stroke Rehabil ; 21(2): 137-51, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24710974

RESUMEN

PURPOSE: The aim of the present study was to evaluate the effect of applying electroencephalogram (EEG) biofeedback (neurobiofeedback) or electromyographic (EMG) biofeedback to conventional occupational therapy (OT) on improving hand function in stroke patients. METHODS: This study was designed as a preliminary clinical trial. Thirty patients with stroke were entered the study. Hand function was evaluated by Jebsen Hand Function Test pre and post intervention. Patients were allocated to 3 intervention cohorts: (1) OT, (2) OT plus EMG-biofeedback therapy, and (3) OT plus neurofeedback therapy. All patients received 10 sessions of conventional OT. Patients in cohorts 2 and 3 also received EMG-biofeedback and neurofeedback therapy, respectively. EMG-biofeedback therapy was performed to strengthen the abductor pollicis brevis (APB) muscle. Neurofeedback training was aimed at enhancing sensorimotor rhythm after mental motor imagery. RESULTS: Hand function was improved significantly in the 3 groups. The spectral power density of the sensorimotor rhythm band in the neurofeedback group increased after mental motor imagery. Maximum and mean contraction values of electrical activities of the APB muscle during voluntary contraction increased significantly after EMG-biofeedback training. CONCLUSION: Patients in the neurofeedback and EMG-biofeedback groups showed hand improvement similar to conventional OT. Further studies are suggested to assign the best protocol for neurofeedback and EMG-biofeedback therapy.


Asunto(s)
Electromiografía , Mano/fisiopatología , Neurorretroalimentación , Recuperación de la Función , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/fisiopatología , Adulto , Algoritmos , Estudios de Cohortes , Electroencefalografía , Electromiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espasticidad Muscular/etiología , Espasticidad Muscular/rehabilitación , Músculo Esquelético/fisiopatología , Neurorretroalimentación/métodos , Terapia Ocupacional , Sensación , Resultado del Tratamiento , Muñeca/fisiopatología
13.
Appl Opt ; 53(7): 1449-58, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24663375

RESUMEN

A key issue with surface plasmon resonance (SPR) biosensors, which are the focus of many researchers, is improving their sensitivity to detect lower amounts of analyte in a solution. Most SPR developments have focused on the grating-based sensitivity-enhancement approach. In addition to sensitivity, a substantial enhancement of other sensor characteristics such as resolution and signal-to-noise ratio (SNR) is desired for designing a practical sensor. So, in this paper, the characteristics of surface plasmon polaritons sustained by 1D subwavelength metallic gratings on a thin metal slab (under the Krestchmann configuration) have been investigated numerically for the analyte-ligand interactions detection. Effects of different structural parameters, such as grating period, grating depth, metal film thickness, and fill factor have been evaluated on the sensor sensitivity as well as resolution and SNR. Numerical results indicate that the sensor working in the near-infrared wavelength has a better performance than that in the visible one. The result of numerical investigation has been used to design an optimized sensor with the best figure of merit.


Asunto(s)
Técnicas Biosensibles/instrumentación , Diseño Asistido por Computadora , Modelos Teóricos , Nanotecnología/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Rayos Infrarrojos , Luz , Dispersión de Radiación
14.
Sci Rep ; 3: 1952, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23739609

RESUMEN

Collapse models provide a theoretical framework for understanding how classical world emerges from quantum mechanics. Their dynamics preserves (practically) quantum linearity for microscopic systems, while it becomes strongly nonlinear when moving towards macroscopic scale. The conventional approach to test collapse models is to create spatial superpositions of mesoscopic systems and then examine the loss of interference, while environmental noises are engineered carefully. Here we investigate a different approach: We study systems that naturally oscillate-creating quantum superpositions-and thus represent a natural case-study for testing quantum linearity: neutrinos, neutral mesons, and chiral molecules. We will show how spontaneous collapses affect their oscillatory behavior, and will compare them with environmental decoherence effects. We will show that, contrary to what previously predicted, collapse models cannot be tested with neutrinos. The effect is stronger for neutral mesons, but still beyond experimental reach. Instead, chiral molecules can offer promising candidates for testing collapse models.

16.
Phys Chem Chem Phys ; 14(25): 9214-8, 2012 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-22643869

RESUMEN

The superposition of chiral states of chiral molecules, as delocalized quantum states of a many-particle system, can be used for the experimental investigations of decoherence theory. In this regard, a great challenge is the precise quantification of the robustness of these superpositions against environmental effects. The methods so far proposed need the detailed specification of the internal states of the molecule, usually requiring heavy numerical calculations. Here, by using the linearized quantum Boltzmann equation and by borrowing ideas employed for analyzing other quantum systems, we present a general and simple approach, of wide applicability, which can be used to compute the dominant contribution to the decoherence rate for the superpositions of chiral states of chiral molecules, due to environmental scattering.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(2 Pt 2): 026318, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22463328

RESUMEN

In this study, effects of microstructure on the viscous permeability and Forchheimer coefficient of monodispersed fibers are investigated. The porous material is represented by a unit cell which is assumed to be repeated throughout the medium. Based on the orientation of the fibers in the space, fibrous media are divided into three categories: one-, two-, and three-directional (1D, 2D, and 3D) structures. Parallel and transverse flow through square arrangements of 1D fibers, simple 2D mats, and 3D simple cubic structures are solved numerically over a wide range of porosity (0.35 < ε < 0.95) and Reynolds number (0.01 < Re < 200). The results are used to calculate the permeability and the inertial coefficient of the considered geometries. An experimental study is performed; the flow coefficients of three different ordered tube banks in the moderate range of Reynolds number (0.001 < Re < 15) are determined. The numerical results are successfully compared with the present and the existing experimental data in the literature. The results suggest that the permeability and Forchheimer coefficient are functions of porosity and fiber orientation. A comparison of the experimental and numerical results with the Ergun equation reveals that this equation is not suitable for highly porous materials. As such, accurate correlations are proposed for determining the Forchheimer coefficient in fibrous porous media.


Asunto(s)
Hidrodinámica , Microtecnología/métodos , Modelos Teóricos , Porosidad
18.
Vet Parasitol ; 185(2-4): 121-3, 2012 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-22035849

RESUMEN

Microsporidia in dogs and cats is primarily caused by the obligate, intracellular parasite Encephalitozoon cuniculi, which is a member of the phylum Microsporidia. The aim of the current study is the detection of this parasite in stool samples of small animals of Iran, by polymerase chain reaction. Microsporidia spp. was found in 31% (31/100) of dogs (E. cuniculi (18/100), Encephalitozoon bieneusi (8/100) and Encephalitozoon intestinalis (5/100)), and 7.5% (3/40) of the specimens obtained from cats were infected with E. bieneusi. Sequencing of PCR products confirmed these results. In conclusion, Microsporidia infection seems to be fairly common in pet animals of Iran, especially in dogs. This finding could indicate the importance of pet animals as zoonotic reservoirs of microsporidial human infections.


Asunto(s)
Enfermedades de los Gatos/parasitología , Enfermedades de los Perros/parasitología , Microsporida/aislamiento & purificación , Microsporidiosis/veterinaria , Animales , Enfermedades de los Gatos/epidemiología , Gatos , ADN Protozoario/clasificación , ADN Protozoario/aislamiento & purificación , Enfermedades de los Perros/epidemiología , Perros , Composición Familiar , Heces/parasitología , Humanos , Irán/epidemiología , Microsporida/clasificación , Microsporidiosis/epidemiología , Mascotas , Reacción en Cadena de la Polimerasa/veterinaria , Zoonosis
19.
Eur J Phys Rehabil Med ; 47(3): 381-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21946400

RESUMEN

BACKGROUND: Myofascial pain syndrome (MPS) is one of the most prevalent musculoskeletal diseases. MPS impaired quality of life in the patients. There is a lot of controversy about different treatment options which include medical treatments, physical therapy, injections, ultrasound and laser. The effects of laser in MPS are challenging. AIM: To assess the effects of laser and ultrasound in treatment of MPS. DESIGN: Randomized single blinded clinical trial SETTING: Outpatient physical therapy clinic at university hospital POPULATION: Sixty three subjects (females: 46, males: 17), (age range: 17-55 year old) who had a diagnosis of definite MPS were entered in the study. METHODS: We measured the pain intensity at rest, during activity and at night using Visual Analogue Scale (VAS) questionnaire. The patients also filled the Neck Disability Index (NDI) form and the pain threshold provoked by pressure was determined using algometric assessment. Then, the patients were categorized randomly in groups A, B and C (receiving laser therapy, ultrasound and sham laser therapy, respectively). Six weeks after the initial visit, they were visited again and filled the forms again. RESULTS: Ultrasound was effective in VAS improvement during activity (46%), at rest (39%) and at night (35%). It also improved NDI scores (34%) and algometric assessment (37%). Laser was effective in VAS improving during activity (54%), at night (51%) and at rest (51%) and also improved NDI scores (73%). It was also found effective in algometric assessment improvement (105%). Laser resulted in more NDI score and algometric assessment improvements comparing to ultrasound (p<0.05). CONCLUSION: This study introduces laser as one of the preferred treatments of myofascial pain syndrome in shoulder.


Asunto(s)
Terapia por Luz de Baja Intensidad/métodos , Síndromes del Dolor Miofascial/terapia , Terapia por Ultrasonido/métodos , Adolescente , Adulto , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Método Simple Ciego , Resultado del Tratamiento
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 83(4 Pt 2): 046301, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21599289

RESUMEN

We propose a methodology for swimming at low-Reynolds-number flows based on ciliary motion of a microswimmer using magnetic actuation of artificial cilia. By solving the coupled magnetic-elastic-hydrodynamic problem, we demonstrate nonreciprocal effective and recovery strokes for cilia that nicely mimic natural cilia beating. Cilia drag forces, microswimmer net displacement, velocity, and efficiency are calculated, and we show the model can swim using a prespecified magnetic actuation. The proposed methodology can be used for devising biomedical microdevices that swim in viscous flows inside the human body.

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