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1.
Opt Express ; 30(25): 44628-44639, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36522884

RESUMEN

We theoretically and numerically investigate the performance of tilted Bragg gratings in planar waveguides, fabricated by direct UV writing in photosensitive silica, to couple light out of a chip. An analytic expression is derived for the coupling efficiency and validated numerically by finite element simulations. Using the analytic result, we can design gratings to generate output beams in free space of any specific shape and calculate their overall power coupling efficiency. Our simulations indicate that for currently achievable grating index contrasts devices of millimeter length are most suitable for this technology.

2.
Front Psychol ; 13: 701856, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35602704

RESUMEN

Digital literacy is becoming more important because of the skillset of functioning in online is becoming a necessary skill set in daily life. The purpose of this study was to examine the association between loneliness and digital literacy and the mediation effect of motivation in that association. Also, this study examined the moderating effect of mindset in the meditation effect of motivation in the association between loneliness and digital literacy. 287 respondents were recruited from online survey in United States. To investigate the direct effect of loneliness on digital literacy, the mediating effect of motivation, and the moderating of mindset on the mediating effect, this research employed a mediated moderation model. The findings of this research suggest that prevention-focused motivation mediated the effect of loneliness on digital literacy and the effect was moderated by a fixed mindset (as opposed to a growth mindset). The result of the study contributes to the literature by examining how loneliness could impede acquiring digital literacy through prevention-focused motivation and fixed mindset.

3.
ACS Appl Mater Interfaces ; 12(44): 49386-49397, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-32948093

RESUMEN

This study examined whether neonatal chicken bone marrow cells (cBMCs) could support the osteogenesis of human stromal cells in a three-dimensional (3D) extracellular bioprinting niche. The majority (>95%) of 4-day-old cBMCs subcultured 5 times were positive for osteochondrogenesis-related genes (Col I, Col II, Col X, aggrecan, Sox9, osterix, Bmp2, osteocalcin, Runx2, and osteopontin) and their related proteins (Sox9, collagen type I, and collagen type II). LC-MS/MS analysis demonstrated that cBMC-conditioned medium (c-medium) contained proteins related to bone regeneration, such as periostin and members of the TGF-ß family. Next, a significant increase in osteogenesis was detected in three human adipose tissue-derived stromal cell (hASC) lines, after exposure to c-medium concentrates in 2D culture (p < 0.05). To evaluate biological function in a 3D environment, we employed the cBMC-derived bioactive components as a cell-supporting biomaterial in collagen bioink, which was printed to construct a 3D hASC-laden scaffold for observing osteogenesis. Complete osteogenesis was detected in vitro. Moreover, after transplantation of the hASC-laden structure into rats, prominent bone formation was observed compared with that in control rats receiving scaffold-free hASC transplantation. These results demonstrated that substance(s) secreted by chick bone marrow cells clearly activated the osteogenesis of hASCs in 2D- or 3D-niches.


Asunto(s)
Bioimpresión , Células de la Médula Ósea/citología , Tinta , Impresión Tridimensional , Células del Estroma/citología , Animales , Células Cultivadas , Embrión de Pollo , Pollos , Humanos , Estructura Molecular , Osteogénesis , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie
4.
Asian-Australas J Anim Sci ; 31(3): 335-343, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28823125

RESUMEN

OBJECTIVE: Remarkable difference in cellular activity was found between early and late subpassaged embryonic stem cell (ESCs) lines, which can be created by subtle changes in cell manipulation protocol. This study subsequently examined whether post-thaw subculture of early subpassaged ESC lines could further affect the activity of the ESCs. METHODS: Fresh (as a control treatment) or cryopreserved F1 hybrid (B6CBAF1) early ESC lines (C57BL/6xCBA) of the 4 (P4) or the 19 passage (P19) were subcultured once, twice or six times under the same condition. The post-thaw survival of the ESCs was monitored after the post-treatment subculture and the ability of cell proliferation, reactive oxygen species (ROS) generation, apoptosis and mitochondrial ATP synthesis was subsequently examined. RESULTS: Regardless of the subculture number, P19 ESCs showed better (p<0.05) doubling time and less ATP production than P4 ESCs and such difference was not influenced by fresh or cryopreservation. The difference between P4 and P19 ESC lines became decreased as the post-treatment subculture was increased and the six times subculture eliminated such difference. Similarly, transient but prominent difference in ROS production and apoptotic cell number was detected between P4 and P19 ESCs only at the 1st subculture after treatment, but no statistical differences between two ESC lines was detected in other observations. CONCLUSION: The results of this study suggest that post-thaw subculture of ESCs under the same environment is recommended for standardizing their cellular activity. The activity of cell proliferation ability and ATP synthesis can be used as parameters for quality control of ESCs.

5.
Mol Cells ; 40(8): 558-566, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28756654

RESUMEN

Regular monitoring on experimental animal management found the fluctuation of ART outcome, which showed a necessity to explore whether superovulation treatment is responsible for such unexpected outcome. This study was subsequently conducted to examine whether superovulation treatment can preserve ultrastructural integrity and developmental competence of oocytes following oocyte activation and embryo culture. A randomized study using mouse model was designed and in vitro development (experiment 1), ultrastructural morphology (experiment 2) and functional integrity of the oocytes (experiment 3) retrieved after PMSG/hCG injection (superovulation group) or not (natural ovulation; control group) were evaluated. In experiment 1, more oocytes were retrieved following superovulation than following natural ovulation, but natural ovulation yielded higher (p < 0.0563) maturation rate than superovulation. The capacity of mature oocytes to form pronucleus and to develop into blastocysts in vitro was similar. In experiment 2, a notable (p < 0.0186) increase in mitochondrial deformity, characterized by the formation of vacuolated mitochondria, was detected in the superovulation group. Multivesicular body formation was also increased, whereas early endosome formation was significantly decreased. No obvious changes in other microorganelles, however, were detected, which included the formation and distribution of mitochondria, cortical granules, microvilli, and smooth and rough endoplasmic reticulum. In experiment 3, significant decreases in mitochondrial activity, ATP production and dextran uptake were detected in the superovulation group. In conclusion, superovulation treatment may change both maturational status and functional and ultrastuctural integrity of oocytes. Superovulation effect on preimplantation development can be discussed.


Asunto(s)
Diferenciación Celular , Oocitos/citología , Oocitos/ultraestructura , Superovulación/fisiología , Animales , Diferenciación Celular/efectos de los fármacos , Gonadotropina Coriónica/farmacología , Dextranos , Combinación de Medicamentos , Femenino , Fluoresceína-5-Isotiocianato/metabolismo , Gonadotropinas Equinas/farmacología , Caballos , Humanos , Masculino , Ratones Endogámicos C57BL , Oocitos/efectos de los fármacos , Orgánulos/efectos de los fármacos , Orgánulos/metabolismo , Superovulación/efectos de los fármacos
6.
Res Social Adm Pharm ; 10(2): 398-407, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23988694

RESUMEN

BACKGROUND: Most U.S. states had over 50 Medicare Prescription Drug Plans (PDPs) in 2007. Medicare beneficiaries are expected to switch Part D plans based on their health and financial needs; however, the switching rate has been low. Such consumer inertia potentially has negative effects on both beneficiaries and the insurance market, resulting in a critical need to investigate its cause. OBJECTIVES: To 1) describe how Medicare beneficiaries who were satisfied with their current Part D plan differed from those who were not satisfied; 2) examine the effect of switching costs on consideration of switching among Medicare beneficiaries who were dissatisfied with their current Part D plan. METHODS: Data from the 2007 Prescription Drug Study supplement to the Health and Retirement Study (HRS) survey were used in this study. The satisfied and dissatisfied groups were compared in terms of cost variables, switching costs, and perception of Part D complexity. Structural equation modeling was used to examine relationships among switching costs, Part D complexity, cost variables, and consideration of switching for beneficiaries who were dissatisfied with their current Part D coverage. RESULTS: Out of 467 participants, a total of 255 (54.6%) were satisfied with their current Part D plan. The satisfied group paid lower out-of-pocket costs ($50.63 vs. $114.60) and premiums ($30.88 vs. $40.77) than the dissatisfied group. They also had lower switching costs. Only 11.3% of the dissatisfied beneficiaries switched plans. Among respondents who were dissatisfied with their current plan, those who perceived Part D as complex had high switching costs and were less likely to consider switching plans. Out-of-pocket cost did not have a statistically significant association with consideration of switching. CONCLUSIONS: Medicare beneficiaries who were satisfied with their current Part D plans had lower out-of-pocket costs and premiums as well as higher switching costs. Among beneficiaries who were dissatisfied with their current Part D plan, those who had higher switching costs were less likely to consider switching Part D plans.


Asunto(s)
Medicare Part D , Satisfacción del Paciente , Anciano , Conducta de Elección , Femenino , Humanos , Masculino , Persona de Mediana Edad , Honorarios por Prescripción de Medicamentos , Estados Unidos
7.
Korean J Urol ; 51(1): 25-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20414406

RESUMEN

PURPOSE: We performed a comparative analysis of the plasma levels of antithrombin (AT) III, plasminogen, fibrinogen, and D-dimer among patients with and without clinically localized prostate cancer to investigate the clinical significance of the coagulation profile in prostate cancer. MATERIALS AND METHODS: A prospective study was performed in which plasma levels of AT III, plasminogen, fibrinogen, and D-dimer were assessed in patients before they underwent prostate biopsy. According to the results of the biopsy, the patients were categorized into the cancer group or the control group. Levels of the four coagulation factors were then compared between the cancer and control groups. Also, levels of the four coagulation factors were correlated with tumor stage and grade in the cancer group. RESULTS: The cancer group had significantly lower levels of AT III activity and higher plasma D-dimer levels than did the control group (p=0.007 and p=0.018, respectively). Within the cancer group, no significant differences were observed in the levels of AT III, plasminogen, fibrinogen, or D-dimer between those with a pathological Gleason score of >/=7 and otherwise. Regarding pathologic stage of prostate cancer, the subjects with organ-confined disease and those with extraprostatic extension of a tumor demonstrated no significant differences in the preoperative levels of the four coagulation factors analyzed. CONCLUSIONS: Our results suggest that plasma levels of AT III and D-dimer are altered in patients with prostate cancer. Further study is needed to elucidate the underlying mechanism and clinical significances of such a phenomenon among patients with clinically localized prostate cancer.

8.
Urology ; 75(6): 1467-71, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19962734

RESUMEN

OBJECTIVES: To evaluate the association of prostatic urethral angle (PUA) with bladder outlet obstruction (BOO) index in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). METHODS: A retrospective analysis was made of 260 men with LUTS and/or BPH aged>50 years (median: 65.9, range: 50-87). Patients underwent an evaluation including the International Prostatic Symptom Score, serum prostate-specific antigen levels, transrectal ultrasonography, frequency-volume chart, uroflowmetry, and measurement of postvoid residual, and multichannel video urodynamic study with a pressure-flow study. RESULTS: Patients with higher PUA (PUA>or=35 degrees) had higher prostate-specific antigen levels (P=.043), larger prostate volume (P<.001), higher maximal urethral closure pressure (P=.004), higher detrusor pressure at maximum flow rate (P=.008), and higher BOO index (P=.032), in comparison with those who had lower PUA (PUA<35 degrees). There was no significant difference of PUA values according to the degree of intravesical prostatic protrusion. When we compared BOO index according to PUA, patients with higher PUA had higher BOO index than those with lower PUA (30.6+/-1.8 vs 23.6+/-1.8, P=.006). The area under the curve of PUA was significant for BOO (area, 63.0%; 95% confidence interval, 55.1%-70.9%; P=.002). CONCLUSIONS: PUA may be one method to asses the presence of BOO in men with LUTS and/or BPH. Our findings suggest that PUA may help in the treatment of individuals by better predicting their likely classification from a pressure-flow study.


Asunto(s)
Hiperplasia Prostática/complicaciones , Prostatismo/complicaciones , Uretra/fisiopatología , Obstrucción del Cuello de la Vejiga Urinaria/complicaciones , Trastornos Urinarios/complicaciones , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Estudios de Cohortes , Endosonografía/métodos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Probabilidad , Antígeno Prostático Específico/sangre , Hiperplasia Prostática/diagnóstico por imagen , Prostatismo/diagnóstico por imagen , Recto , Valores de Referencia , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico por imagen , Trastornos Urinarios/diagnóstico por imagen , Urodinámica
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