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Hybrid transparent contacts based on combinations of a transparent conductive oxide and a few graphene monolayers were developed in order to evaluate their optical and electrical performance with the main aim to use them as front contacts in optoelectronic devices. The assessment of the most suitable strategies for their fabrication was performed by testing different protocols addressing such issues as the protection of the device structure underneath, the limitation of sample temperature during the graphene-monolayer transfer process and the determination of the most suitable stacking structure. Suitable metal ohmic electrodes were also evaluated. Among a number of options tested, the metal contact based on Ti + Ag showed the highest reproducibility and the lowest contact resistivity. Finally, with the objective of extracting the current generated from optoelectronic devices to the output pins of an external package, focusing on a near future commercial application, the electrical properties of the connections made with an ultrasonic bonding machine (sonic welding) between the optimized Ti + Ag metal contacts and Al or Au micro-wires were also evaluated. All these results have an enormous potential as hybrid electrodes based on graphene to be used in novel designs of a future generation of optoelectronic devices, such as solar cells.
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New architectures of transparent conductive electrodes (TCEs) incorporating graphene monolayers in different configurations have been explored with the aim to improve the performance of silicon-heterojunction (SHJ) cell front transparent contacts. In SHJ technology, front electrodes play an important additional role as anti-reflectance (AR) coatings. In this work, different transparent-conductive-oxide (TCO) thin films have been combined with graphene monolayers in different configurations, yielding advanced transparent electrodes specifically designed to minimize surface reflection over a wide range of wavelengths and angles of incidence and to improve electrical performance. A preliminary analysis reveals a strong dependence of the optoelectronic properties of the TCEs on (i) the order in which the different thin films are deposited or the graphene is transferred and (ii) the specific TCO material used. The results shows a clear electrical improvement when three graphene monolayers are placed on top on 80-nm-thick ITO thin film. This optimum TCE presents sheet resistances as low as 55 Ω/sq and an average conductance as high as 13.12 mS. In addition, the spectral reflectance of this TCE also shows an important reduction in its weighted reflectance value of 2-3%. Hence, the work undergone so far clearly suggests the possibility to noticeably improve transparent electrodes with this approach and therefore to further enhance silicon-heterojunction cell performance. These results achieved so far clearly open the possibility to noticeably improve TCEs and therefore to further enhance SHJ contact-technology performance.
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BACKGROUND: Despite suffering high ultraviolet radiation levels, few data on malignant melanoma (MM) in Macaronesia are available. METHODS: Observational study of cutaneous MM cases diagnosed during a period of 12 years at a tertiary hospital in Canary Islands. RESULTS: A total of 532 patients (female/male = 1.4) with an average age of 56 years were included; 5% developed more than one MM, and 7% reported family history of MM. Phototype II (43%), dark eyes (41%), and dark hair (41%) predominated. There was a lower frequency of light-colored hair and eyes in those born in the Canary Islands. The most frequent locations of MM were on the back for men (37%) and on the lower extremities for women (35%). Among the infiltrating tumors (83%), the (median) thickness was 1.07 mm (women, 0.90 mm; men, 1.21 mm). Anatomopathological ulceration (AU) and a mitotic rate ≥1 mitosis/mm2 (HMR) were recorded in 27% of patients. Patients with regional disease constituted 12% of the population. The most common stage was IA (34%). Melanoma-specific survival (MSSV) decreased significantly with thickness, presence of AU, HMR, and sentinel lymph node disease. These four variables were independent prognostic factors. The five-year MSSV varied between 100% (stage IA) and 39% (stage IIIC). CONCLUSIONS: The characteristics of the patients were similar to those published in datasets from continental Europe, although the pigmentary features were darker in those originating from Macaronesia. The prognostic parameters described in the 7th edition of the American Joint Committee on Cancer (AJCC) independently predict MSSV in our patients.
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Melanoma/epidemiología , Neoplasias Primarias Múltiples/patología , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Islas del Atlántico/epidemiología , Color del Ojo , Femenino , Color del Cabello , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Melanoma/complicaciones , Melanoma/secundario , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Neoplasias Cutáneas/complicaciones , Pigmentación de la Piel , Úlcera Cutánea/etiología , España/epidemiología , Tasa de Supervivencia , Centros de Atención Terciaria , Carga Tumoral , Adulto JovenRESUMEN
Objetivo: Debido a que las Toxiinfecciones alimentarias (TIA) originan daños para la salud, pérdidas económicas y requieren la intervención directa sobre la fuente de contaminación, el objetivo fue realizar un estudio clínico, epidemiológico e higiénico sanitario de un brote de TIA, sin posibilidad de análisis microbiológico. Diseño: Estudio descriptivo y de casos-controles. Emplazamiento: Comunidad de Munera. Albacete (España). Participantes: Población compuesta por las personas asistentes a tres comidas de celebración de comunión. Mediciones Principales: Se realizó una encuesta telefónica epidemiológica y se calcularon odds ratio (OR) crudas y ajustadas con intervalos de confianza al 95 %. Se realizó un modelo de regresión logística multivariante e inspección sanitaria del restaurante. Resultados: Se expusieron 204 personas y fueron encuestadas 62 (32 afectados y 30 sanos). La tasa global de ataque fue de 51,6 % y el periodo de incubación de 33 horas. Los síntomas principales: dolor abdominal, vómitos y diarreas. El tiempo de duración de la enfermedad fue 38 horas. Se observó asociación con la "Ensalada" (OR-cruda: 7,5; IC95: 1,48-37,91), resultando al borde de la significación estadística la relación con "Sepia" (ORc: 4,15; IC95: 1,00-17.18) y "Marisco" (ORc: 4,57; IC95: 0,87-24,08). La OR-ajustada para la "Ensalada" fue 5,41 (IC95: 1,00-29,23). La inspección sanitaria comprobó la existencia de deficiencias de estructura, limpieza, desinfección y formación de manipuladores. Conclusiones: La Ensalada fue el único alimento asociado estadísticamente, pero no podemos descartar la Sepia y Mariscos; mediante la inspección sanitaria y los criterios de Kaplan, es posible clasificarla como una infección por Norovirus. Se aplicaron medidas especiales de funcionamiento en el restaurante para evitar reincidencia del brote (AU)
Objective: Because Foodborne diseases (FBD) cause health damage, financial losses, and require direct intervention at the source of contamination, our aim was to carry out a clinical, epidemiological, and hygienic study of an outbreak of FBD, without the possibility of conducting a microbiological analysis. Design: A descriptive and case-control study. Location: Community of Munera, Albacete (Spain). Participants: Population composed of the attendees to three first communion celebrations. Main measurements: An epidemiological telephone survey was made, and crude and adjusted odds ratios (OR) were calculated with confidence intervals of 95%. A multivariate logistic regression model, and restaurant health inspection were also performed. Results: 204 people exposed, 62 respondents (32 affected and 30 healthy); global infection rate: 51.6%, and incubation period: 33 hours; main symptoms: abdominal pain, vomiting, and diarrhea; duration of disease: 38 hours. Statistical analysis showed associations with the consumption of three foodstuff. "Salad" crude OR 7.5 IC95(1.48-37.91), "Cuttlefish" crude OR 4.15 IC95(1,00-17.18) and "Seafood" crude OR 4.57 IC95(0.87-24.08). The adjusted-OR for the "Salad" is 5.41 IC95(1.00-29.23). The health inspection found the existence of deficiencies in structure, cleaning, disinfection and food handling training. Conclusions: The Salad was the only food statistically associated with the infection, but Cuttlefish and Seafood cannot be ruled out. Through sanitary inspection and Kaplans criteria, this can be classified as a Norovirus infection. Special performance measures were applied in the restaurant to prevent recurrence of the outbreak (AU)
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Humanos , Masculino , Femenino , 50328 , Microbiología de Alimentos/métodos , Microbiología de Alimentos/tendencias , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/rehabilitación , Norovirus/inmunología , Norovirus/aislamiento & purificación , Entrevistas como Asunto/métodos , Entrevistas como Asunto , Higiene Alimentaria/métodos , Higiene Alimentaria/normas , Estudios de Casos y Controles , Encuestas sobre Dietas/métodos , Encuestas sobre Dietas/estadística & datos numéricos , Oportunidad Relativa , Modelos Logísticos , Análisis Multivariante , Intervalos de ConfianzaRESUMEN
Several MC1R variants are associated with increased risk of malignant melanoma (MM) in a variety of populations. We aim to examine the influence of the MC1R variants (RHC: D84E, R151C, R160W; NRHC: V60L, R163Q and the synonymous polymorphism T314T) on the MM risk in a population from the Canary Islands. Overall, 1,046 Caucasian individuals were included in the study. A thousand of them were genotyped for MC1R variants: 509 were sporadic MM patients and 491 were healthy control subjects from general population. The analysis was adjusted for age, sex, hair colour, eye colour, skin phototype and ancestry. We found that carriers of the R151C and R163Q variants were at an increased risk for melanoma OR 2.76 (1.59-4.78) and OR 5.62 (2.54-12.42), respectively. The risk of carrying RHC variants was 3.04 (1.90-4.86). Current study confirms the increased MM risk for R151C carriers. It also supports the association between R163Q variant and MM risk in the population on the Canary Islands, as opposed to reported on northern populations. These results highlight the importance of the sample population selection in this kind of studies.
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Melanoma/epidemiología , Melanoma/genética , Receptor de Melanocortina Tipo 1/genética , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Riesgo , Pigmentación de la Piel/genética , España/epidemiologíaRESUMEN
AIMS: Evaluation of the accuracy of palpation, CT scan and Martínez-Gimeno Score System in the assessment of neck nodes metastasis in squamous cell carcinoma of the oral cavity. DESIGN: This is a prospective triple blind study performed in 40 consecutive patients with squamous cell carcinoma of the oral cavity. PATIENTS: 40 consecutive patients suffering primary oral squamous cell carcinoma, without any treatment before surgery, palpation or CT Scan. RESULTS: 40% of the cases showed metastasis in pathological study. Sensitivity was 100%, 94% and 75% for MGSS 13, CT scan and palpation, respectively. Specificity was 83%, 38% and 25-50% for palpation, CT scan and MGSS 13-17, respectively. Negative predictive result values were 100%, 90% and 83% for MGSS 13, CT Scan and palpation. The logistic regression analysis showed an independent predictor factor for palpation (p=0.001) and MGSS (p=0.01). The combination of MGSS and clinical palpation allowed a new design for evaluating neck metastasis in oral cancer. This method establishes 3 different groups at risk: 3 of very low (<2%), 2 of low risk (18-27%) and 1 of high risk (85%). CONCLUSIONS: MGSS predicts metastasis better than CT scan and palpation. Combination of MGSS and palpation improves the prediction of metastasis.
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Carcinoma de Células Escamosas/patología , Metástasis Linfática/diagnóstico , Neoplasias de la Boca/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/secundario , Método Doble Ciego , Femenino , Humanos , Modelos Logísticos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Cuello , Disección del Cuello/estadística & datos numéricos , Clasificación del Tumor/métodos , Palpación , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Alpha-melanocyte-stimulating hormone receptor 1 (MC1R) has an important role in skin pigmentation and variants of the gene have been established as independent risk factors for susceptibility to cutaneous malignant melanoma. OBJECTIVE: To explore whether variants of the gene also influence the onset of the disease. METHODS: We analyzed 285 melanoma patients of European ancestry for common variation in codon 84 (D84E) of the alpha-MSH receptor 1 gene, which is known to have functional consequences in MC1R protein activity. RESULTS: The mean age difference at diagnosis between MC1R 84E carriers and non-carriers was 9 years (95% confidence interval [CI]: 2-17; p=0.012), with 84E non-carrier patients being older. After adjusting for gender, Clark's level, phototype, eyes and hair colour, the risk for cutaneous malignant melanoma at any age was 2.07 times higher (95% CI: 1.21-3.52; p=0.008) among MC1R 84E carriers. Enrolment criteria, geographical origin, Clark's levels and Breslow's indexes were similar between MC1R 84E carriers and non-carriers. Further analyses based on the Clark level and Breslow's index, both indicative for cancer invasion, reasonably supported an unbiased selection of patients during the study enrolment. Additional exon re-sequencing of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene in MC1R 84E carriers ruled out the presence of high penetrance mutations that have previously been associated with early onset of the disease. CONCLUSION: Although our findings need to be confirmed by independent and larger studies we have described for the first time the association of D84E variant of the alpha-MSH receptor 1 gene as an independent risk factor for an earlier onset of cutaneous malignant melanoma.
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Melanoma/genética , Receptores de la Hormona Hipofisaria/genética , Neoplasias Cutáneas/genética , Adulto , Edad de Inicio , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , MutaciónRESUMEN
BACKGROUND: The prediction of neck metastasis from oral squamous cell carcinoma is an unresolved issue. The Martinez-Gimeno Scoring System (MGSS) is an index designed as a predictive aid that may be implemented after analysis of the tumor resection. METHODS: A double-blind cohort study was designed and carried out in a tertiary hospital. Seventy-nine consecutive patients diagnosed with squamous cell carcinoma of the oral cavity requiring local resection and neck dissections were included. After tumor resection, the MGSS was applied, and patients were then classified into one of four groups on the basis of the MGSS score: group I, 7 to 12 points; group II, 13 to 16 points; group III, 17 to 20 points; and group IV, 21 to 30 points. After this, pathologic analysis of the neck specimen was performed to detect metastasis. The results, histopathologic analysis of the neck specimens, and previously tabulated MGSS scores were then compared, and on the basis of their results an estimation of the predictive validity of MGSS of neck metastases was obtained. A correlational analysis was performed, comparing metastases to a set of predictive factors, including the MGSS score. A logistic binary regression model that used metastases as the dependent variable was adjusted in an attempt to estimate odd ratios for these factors. RESULTS: Twenty-six cases displayed metastases. The metastatic nodes measured from 0.5 to 7 cm and were smaller than 1.5 cm in 46% of the cases. The rates of metastases in the four groups were as follows: group 1, 0%; group II, 21%; group III, 50%; and group IV, 67%. MGSS had a sensitivity of 100% (95% confidence interval [CI], 98% to 100%) for predicting metastases from oral squamous cell carcinoma, a specificity of 55% (95% CI, 44% to 66%), an overall efficiency of 73% (95% CI, 63% to 83%), a positive predictive value of 59% (95% CI, 48% to 70%), and a negative predictive value of 100% (95% CI, 98% to 100%). The correlation between various predictive factors and the presence of metastases showed a value of r = .87 (p = .001) with the MGSS score. No correlation was found between the MGSS score and the size of the metastatic lymph node. In the logistic regression model, the MGSS score displayed an odds ratio of 3.5 (95% CI, 1.9-6.3; p = .00001) for the presence of metastases in patients with squamous cell carcinoma of the oral cavity. CONCLUSION: The MGSS is a useful index for the prediction of neck node metastases that is applied at the start of the analysis of the tumor resection in patients with squamous cell carcinoma of the oral cavity.