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1.
Appl Opt ; 62(8): C30-C37, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-37133054

RESUMEN

In recent years, an unconventional excitation of trivalent neodymium ions (N d 3+) at 1064 nm, not resonant with ground-state transitions, has been investigated with the unprecedented demonstration of a photon-avalanche-like (PA-like) mechanism, in which the temperature increase plays a fundamental role. As a proof-of-concept, N d A l 3(B O 3)4 particles were used. A consequence of the PA-like mechanism is the absorption enhancement of excitation photons providing light emission at a broad range covering the visible and near-infrared spectra. In the first study, the temperature increase was due to intrinsic nonradiative relaxations from the N d 3+ and the PA-like mechanism ensued at a given excitation power threshold (P t h ). Subsequently, an external heating source was used to trigger the PA-like mechanism while keeping the excitation power below P t h at room temperature. Here, we demonstrate the switching on of the PA-like mechanism by an auxiliary beam at 808 nm, which is in resonance with the N d 3+ ground-state transition 4 I 9/2→{4 F 5/2,2 H 9/2}. It comprises the first, to the best of our knowledge, demonstration of an optical switched PA, and the underlying physical mechanism is the additional heating of the particles due to the phonon emissions from the N d 3+ relaxation pathways when exciting at 808 nm. The present results have potential applications in controlled heating and remote temperature sensing.

2.
An Acad Bras Cienc ; 94(4): e20190944, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36449886

RESUMEN

The water retention curve is widely used in studies involving soil. The management systems directly influence soil structure by altering water retention dynamics. Several equations are used to adjust the retention of water in the soil, but most of the time, the choice of these models occurs in an arbitrary way. From this problem, it was proposed with the present study to relate the best mathematical model to water retention, taking into account the different management systems adopted, based on previously established adjustment criteria. For the accomplishment the study, a soil of caulinitic mineralogy and average texture was utilized. The treatments were area under native Cerrado (Savanna), eucalyptus plantation with six and twelve years of cultivation, pasture with two and six years of cultivation, conventional plantation with two and eight years of cultivation, no-till with three and six years of cultivation. From the adjustment criteria for non-linear models, it was found that the management influences the choice of the water retention model. It is possible to observe that the greatest divergences between the models occurred close to the soil saturation zone, and that the Fredlung-Xing model is more efficient in adjusting the water retention curve under conservationist management systems.


Asunto(s)
Eucalyptus , Suelo , Agua
3.
J Prosthet Dent ; 126(6): 804.e1-804.e9, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34654570

RESUMEN

STATEMENT OF PROBLEM: Oxidation heat treatment has been studied to increase the metal-ceramic bond strength. However, information about its use with cobalt-chromium (Co-Cr) alloys is lacking. PURPOSE: The purpose of this study was to evaluate the effect of oxidation heat treatment and oxidation heat treatment with alumina airborne-particle abrasion on the metal-ceramic bond strength of Co-Cr alloys compared with that of nickel-chromium (Ni-Cr) alloys. MATERIAL AND METHODS: In total, 165 metal cylinders (∅5×8 mm) made of 5 base metal alloys were obtained by casting: 2 Ni-Cr (Fit Cast-SB and Fit Cast-V) and 3 Co-Cr alloys (Keragen, StarLoy C, and Remanium 2001). The specimens were divided into groups (n=11): no treatment, oxidation heat treatment, and oxidation heat treatment with airborne-particle abrasion. Oxidation heat treatment was performed starting at 650 °C and rising to 980 °C. The airborne-particle abrasion was performed with 100-µm alumina (0.2-MPa pressure, 5 seconds). One specimen had the surface topography and composition evaluated by scanning electron microscopy and energy dispersive X-ray spectrometry. The feldspathic ceramic was applied to the base metal alloy specimens (n=10). Shear tests were performed to obtain the metal-ceramic bond strength (MPa). The failure modes were evaluated. Data were evaluated by 2-way ANOVA and the Tukey post hoc test, Pearson correlation, and Fisher exact tests (α=.05). RESULTS: The group without treatment showed the highest roughness. The treatments increased oxygen and chromium levels and decreased nickel, molybdenum, and tungsten levels. Oxidation heat treatment provided an increase in metal-ceramic bond strength (P<.05) for base metal alloys with over 7% molybdenum (Fit Cast-SB, Fit Cast-V, and Remanium 2001). With oxidation heat treatment with airborne-particle abrasion, there was improvement only in Fit Cast-SB. No treatment was better for StarLoy C. A weak correlation was found between metal-ceramic bond strength and failure mode (ρ=.166; P=.043). The mixed failures were prevalent in Co-Cr alloys (P<.001) and oxidation heat treatment with airborne-particle abrasion (P=.008). CONCLUSIONS: The oxidation heat treatment was only beneficial for base metal alloy with a molybdenum content of over 7%. Although the oxidation heat treatment with alumina airborne-particle abrasion was a better treatment for Fit Cast-SB, its use is not justified because it showed no difference for oxidation heat treatment and requires another step in the surface treatment.


Asunto(s)
Recubrimiento Dental Adhesivo , Calor , Cerámica , Aleaciones de Cromo , Porcelana Dental , Ensayo de Materiales , Aleaciones de Cerámica y Metal , Resistencia al Corte , Propiedades de Superficie
4.
AME Case Rep ; 3: 4, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30976754

RESUMEN

Xanthogranulomatous orchitis is a rare, non-neoplastic inflammatory condition. We present a case of a 55-year-old diabetic male with an increase in volume, pain and edema in right testicle with a one-year history. The examination involved the investigation of inflammatory markers and ultrasound. Exploration of the scrotum revealed important destruction of the tissue architecture. This case underscores the importance of including xanthogranulomatous orchitis in the differential diagnosis of a testicular lump.

5.
Front Immunol ; 8: 829, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28824608

RESUMEN

At the turn of the last century, the emerging field of medical oncology chose a cytotoxic approach to cancer therapy over an immune-centered approach at a time when evidence in support of either paradigm did not yet exist. Today, nearly 120 years of data have established that (a) even the best cytotoxic regimens only infrequently cure late-stage malignancy and (b) strategies that supplement and augment existing antitumor immune responses offer the greatest opportunities to potentiate durable remission in cancer. Despite widespread acceptance of these paradigms today, the ability of the immune system to recognize and fight cancer was a highly controversial topic for much of the twentieth century. Why this modern paradigmatic mainstay should have been both dubious and controversial for such an extended period is a topic of considerable interest that merits candid discussion. Herein, we review the literature to identify and describe the watershed events that ultimately led to the acceptance of immunotherapy as a viable regimen for the treatment of neoplastic malignancy. In addition to noting important clinical discoveries, we also focus on research milestones and the development of critical model systems in rodents and dogs including the advanced modeling techniques that allowed development of patient-derived xenografts. Together, their use will further our understanding of cancer biology and tumor immunology, allow for a speedier assessment of the efficacy and safety of novel approaches, and ultimately provide a faster bench to beside transition.

6.
Int J Biol Markers ; 32(1): e83-e89, 2017 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-27516000

RESUMEN

BACKGROUND: Serum biomarkers may help to discriminate malignant from benign adnexal masses with equivocal features on imaging. Adequate discrimination of such tumors is crucial for referring patients to either a specialized cancer center or a nonspecialized gynecology service. AIM: We aimed to investigate whether the preoperative level of serum C-reactive protein (CRP), alone or combined with CA125 and menopausal status in the Ovarian Score (OVS), is useful in the prediction of malignancy in women with ovarian tumors. METHODS: This cross-sectional study included 293 patients who underwent surgery in a tertiary cancer center. Receiver operating characteristic (ROC) areas under the curves (AUC) for CRP, CA125 and OVS were calculated in different scenarios, as well as their sensitivity and specificity, using standard cutoff points (for CRP, 10 mg/L; for CA125, 35 U/mL). RESULTS: CA125 and the OVS performed significantly better than CRP alone in the differentiation of benign disease from epithelial ovarian cancer (EOC) (AUC = 0.86 for CA125, 0.79 for OVS, and 0.73 for CRP). OVS and CRP alone were superior to CA125 only in the differentiation of borderline ovarian tumors from advanced stages of EOC and non-EOC. Sensitivity and specificity were 52.5% and 83%, respectively, for CRP, 77.9% and 66.7% for CA125, and 71.3% and 67.8% for OVS. CONCLUSIONS: OVS is as good as CA125 in the differentiation of benign tumors from ovarian cancer. The addition of CA125 and menopausal status to CRP enhanced the relatively low discriminatory power of isolated CRP.


Asunto(s)
Enfermedades de los Anexos/patología , Biomarcadores de Tumor/sangre , Proteína C-Reactiva/análisis , Antígeno Ca-125/sangre , Neoplasias Glandulares y Epiteliales/secundario , Neoplasias Ováricas/secundario , Enfermedades de los Anexos/sangre , Enfermedades de los Anexos/cirugía , Algoritmos , Área Bajo la Curva , Carcinoma Epitelial de Ovario , Estudios Transversales , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Neoplasias Glandulares y Epiteliales/sangre , Neoplasias Glandulares y Epiteliales/cirugía , Neoplasias Ováricas/sangre , Neoplasias Ováricas/cirugía , Pronóstico , Curva ROC
7.
J Appl Oral Sci ; 19(5): 483-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21986653

RESUMEN

OBJECTIVE: Removable partial dentures (RPD) require different hygiene care, and association of brushing and chemical cleansing is the most recommended to control biofilm formation. However, the effect of cleansers has not been evaluated in RPD metallic components. The aim of this study was to evaluate in vitro the effect of different denture cleansers on the weight and ion release of RPD. MATERIAL AND METHODS: Five specimens (12x3 mm metallic disc positioned in a 38x18x4 mm mould filled with resin), 7 cleanser agents [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) (control)] and 2 cobalt-chromium alloys [DeguDent (DD), and VeraPDI (VPDI)] were used for each experimental situation. One hundred and eighty immersions were performed and the weight was analyzed with a high precision analytic balance. Data were recorded before and after the immersions. The ion release was analyzed using mass spectrometry with inductively coupled plasma. Data were analyzed by two-way ANOVA and Tukey HSD post hoc test at 5% significance level. RESULTS: Statistical analysis showed that CT and MI had higher values of weight loss with higher change in VPDI alloy compared to DD. The solutions that caused more ion release were NaOCl and MI. CONCLUSIONS: It may be concluded that 0.05% NaOCl and Medical Interporous tablets are not suitable as auxiliary chemical solutions for RPD care.


Asunto(s)
Aleaciones de Cromo/farmacocinética , Limpiadores de Dentadura/farmacología , Dentadura Parcial Removible , Análisis de Varianza , Biopelículas/efectos de los fármacos , Inmersión , Iones/farmacocinética , Espectrometría de Masas , Ensayo de Materiales , Propiedades de Superficie , Factores de Tiempo
8.
Rev. colomb. cienc. pecu ; 28(1): 83-92, ene.-mar. 2015. ilus, tab
Artículo en Inglés | LILACS | ID: lil-743920

RESUMEN

Background: feed and light are the most important factors affecting the biological rhythms of fish. This work studies fish adaptation to those factors. Objetive: to determine the influence of feeding time and dietary starch and lipid levels on growth, body composition, and liver histology of hybridized Brazilian catfish. Methods: two isoenergetic diets were formulated to contain two levels of crude starch (CHO, %) and lipids (L, %): 5/11 CHO/L and 25/2.2 CHO/L. Sixty animals (260 ± 10 g) were randomly distributed into twelve tanks (100 L). Using self-feeders, two fish groups were fed a diet containing either 5% or 25% starch during the light period (ML), while other two groups were fed the same diets during the dark period (MD). The following parameters were measured: final weight, weight gain, specific growth rate, food intake, hepatosomatic index, and viscerasomatic index. The experiment was carried out in triplicate for 60 days. Results: growth parameters such as specific growth rate (SGR), final weight, and weight gain showed statistical differences between groups, with the best results for the group fed the 25% starch diet during ML. Significant differences between groups on body lipid content, energy, and dry weight were also recorded for those feed 25% starch in the MD. A significant effect was also observed on liver lipid and glycogen content, with values generally higher for ML with 5% starch. Fish fed 25% starch showed significantly lowest lipid and glycogen content during ML. Surprisingly, the opposite occurred regarding liver composition for fish fed in MD. Conclusions: we suggest diurnal feeding should be practiced for optimal performance of juvenile fish, however dark or light phases could be used, taking into consideration its relationship with carbohydrate levels.


Antecedentes: la alimentación y la luz son los factores más importantes que afectan los ritmos biológicos en peces. En este artículo se presenta un poco de conocimiento acerca de la plasticidad de los peces para la utilización del alimento. Objetivo: este estudio se realizó para determinar la influencia del horario de alimentación y los niveles de almidón y lípidos de la dieta en el crecimiento, la composición corporal y la histología hepática en el bagre híbrido. Métodos: fueron formuladas dos dietas isoenergéticas para contener dos niveles de almidón (CHO, %) y lípidos (L, %): 5/11 CHO/L y 25/2.2 CHO/L. Sesenta animales (260 ± 10 g) fueron distribuidos aleatoriamente en 12 tanques (100 L). Un grupo de peces fue alimentado con 5% de almidón en el periodo diurno (ML), y otro grupo fue alimentado en el periodo nocturno (MD). Se realizaron los mismos procedimientos para el grupo alimentado con 25% de almidón. Los siguientes parámetros fueron medidos: peso final, ganancia de peso, tasa de crecimiento especifico, ingestión alimentaria, índice hepatosomático y índice vicerosomático. El experimento se realizó por triplicado durante 60 días. Resultados: los parámetros de crecimiento como la tasa de crecimiento específico (SGR), peso final y ganancia de peso mostraron diferencias estadísticas entre los grupos, con mejores resultados en los grupos alimentados con 25% de almidón en ML. Se observaron diferencias significativas entre los grupos para el contenido de lípidos en el cuerpo, energía y materia seca, para los animales alimentados con 25% de almidón en MD. Hubo un efecto significativo sobre los lípidos hepático y glucógeno, con los valores generalmente más altos en ML para los peces alimentados con 5% de almidón. Sin embargo, los peces alimentados con 25% de almidón presentaron significativamente menor contenido de lípidos y glucógeno en la condición de ML. Sin embargo, ocurrió lo contrario con los peces alimentados en MD, para la composición del hígado. Conclusiones: la alimentación diurna se sugirió para un mejor rendimiento de los juveniles, sin embargo, la fase nocturna o de luz se podrían utilizar, teniendo en cuenta su relación con los niveles de carbohidratos.


Antecedentes: alimentos e luz são os fatores mais importantes que arrastam os ritmos biológicos em peixes. Neste trabalho, trazemos um pouco do conhecimento sobre a plasticidade dos peixes para a utilização dos alimentos. Objetivo: este estudo foi realizado para determinar a influencia do horário de alimentação e níveis de amido e lipídio dietético no crescimento, composição corporal e histologia hepática em um bagre hibrido. Métodos: duas dietas isoenergéticas foram formuladas para conter dois níveis de amido (CHO, %) e lipídeo (L, %): 5/11 CHO/L e 25/2.2 CHO/L. Sessenta animais (260 ± 10 g) foram distribuídos aleatoriamente em 12 tanques (100 L). Um grupo de peixes foi alimentado com 5% de amido no período diurno (ML), e outro grupo foi alimentado no período noturno (MD). Os mesmos procedimentos foram realizados para o grupo que de alimentava com 25% de amido. Os seguintes parâmetros foram medidos: peso final, ganho de peso, taxa de crescimento especifico, consumo, índice hepatossomático y índice vicerossomático. O experimento foi conduzido em triplicado por 60 dias. Resultados: os parâmetros de crescimento como SGR, peso final e ganho de peso mostraram diferença estatística entre os grupos, com melhores resultados nos grupos alimentados com 25% de amido em ML. Diferença significativa entre grupos para conteúdo de lipídio na carcaça, energia e material seca foram observados para os animais alimentados com 25% de amido em MD. Foi observado efeito significativo no lipídio hepático e glicogênio com valores em geral mais altos em ML para os peixes alimentados com 5% de amido. Entretanto, os peixes alimentados com 25% de amido mostraram significativamente baixo conteúdo de lipídio e glicogênio sobre a condição de MD. Surpreendentemente, o oposto correu com os peixes alimentados em MD, para a composição do fígado. Conclusões: a alimentação diurna foi sugerida para um melhor desempenho dos juvenis, no entanto, a fase noturna ou de luz poderiam ser usados , levando em consideração sua relação com os níveis de carboidratos.

9.
ARBS annu. rev. biomed. sci ; 13(n.esp): 23-29, 2011.
Artículo en Inglés | LILACS | ID: lil-619905

RESUMEN

A better understanding of the NK cellreceptor-ligand interaction opened possibilities for new therapeutic strategies. The well known mismatch KIR/HLA interaction is of great importance for NK cell stimulation. Lately, the interaction of the activating receptorDNAM-1 with its ligand PVR, has been highlighted in many ovarian carcinoma studies. Autologous andallogeneic NK cells, along with monoclonal antibodies, have been tested in current immunotherapies. Thisreview presents information on NK cell receptor-ligand interactions and its possibilities for NK-basedimmunotherapy against ovarian cancer.


Asunto(s)
Humanos , Inmunoterapia , Células Asesinas Naturales , Neoplasias Ováricas/terapia , Receptores KIR
10.
J. appl. oral sci ; 19(5): 483-487, Sept.-Oct. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-600849

RESUMEN

OBJECTIVE: Removable partial dentures (RPD) require different hygiene care, and association of brushing and chemical cleansing is the most recommended to control biofilm formation. However, the effect of cleansers has not been evaluated in RPD metallic components. The aim of this study was to evaluate in vitro the effect of different denture cleansers on the weight and ion release of RPD. MATERIAL AND METHODS: Five specimens (12x3 mm metallic disc positioned in a 38x18x4 mm mould filled with resin), 7 cleanser agents [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05 percent sodium hypochlorite (NaOCl), and distilled water (DW) (control)] and 2 cobalt-chromium alloys [DeguDent (DD), and VeraPDI (VPDI)] were used for each experimental situation. One hundred and eighty immersions were performed and the weight was analyzed with a high precision analytic balance. Data were recorded before and after the immersions. The ion release was analyzed using mass spectrometry with inductively coupled plasma. Data were analyzed by two-way ANOVA and Tukey HSD post hoc test at 5 percent significance level. RESULTS: Statistical analysis showed that CT and MI had higher values of weight loss with higher change in VPDI alloy compared to DD. The solutions that caused more ion release were NaOCl and MI. CONCLUSIONS: It may be concluded that 0.05 percent NaOCl and Medical Interporous tablets are not suitable as auxiliary chemical solutions for RPD care.


Asunto(s)
Aleaciones de Cromo/farmacocinética , Dentadura Parcial Removible , Limpiadores de Dentadura/farmacología , Análisis de Varianza , Biopelículas/efectos de los fármacos , Inmersión , Iones/farmacocinética , Espectrometría de Masas , Ensayo de Materiales , Propiedades de Superficie , Factores de Tiempo
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