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1.
Environ Res ; 262(Pt 1): 119802, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39147188

RESUMEN

Forest disturbance regimes across biomes are being altered by interactive effects of global change. Establishing baselines for assessing change requires detailed quantitative data on past disturbance events, but such data are scarce and difficult to obtain over large spatial and temporal scales. The integration of remote sensing with dense time series analysis and cloud computing platforms is enhancing the ability to monitor historical disturbances, and especially non-stand replacing events along climatic gradients. Since the integration of such tools is still scarce in Mediterranean regions, here, we combine dense Landsat time series and the Continuous Change Detection and Classification - Spectral Mixture Analysis (CCDC-SMA) method to monitor forest disturbance in continental Spain from 1985 to 2023. We adapted the CCDC-SMA method for improved disturbance detection creating new spectral libraries representative of the study region, and quantified the year, month, severity, return interval, and type of disturbance (stand replacing, non-stand replacing) at a 30 m resolution. In addition, we characterised forest disturbance regimes and trends (patch size and severity, and frequency of events) of events larger than 0.5 ha at the national scale by biome (Mediterranean and temperate) and forest type (broadleaf, needleleaf and mixed). We quantified more than 2.9 million patches of disturbed forest, covering 4.6 Mha over the region and period studied. Forest disturbances were on average larger but less severe in the Mediterranean than in the temperate biome, and significantly larger and more severe in needleleaf than in mixed and broadleaf forests. Since the late 1980s, forest disturbances have decreased in size and severity while increasing in frequency across all biomes and forest types. These results have important implications as they confirm that disturbance regimes in continental Spain are changing and should therefore be considered in forest strategic planning for policy development and implementation.

2.
Environ Res ; 259: 119432, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38944104

RESUMEN

The Mediterranean Basin has experienced substantial land use changes as traditional agriculture decreased and population migrated from rural to urban areas, which have resulted in a large forest cover increase. The combination of Landsat time series, providing spectral information, with lidar, offering three-dimensional insights, has emerged as a viable option for the large-scale cartography of forest structural attributes across large time spans. Here we develop and test a comprehensive framework to map forest above ground biomass, canopy cover and forest height in two regions spanning the most representative biomes in the peninsular Spain, Mediterranean (Madrid region) and temperate (Basque Country). As reference, we used lidar-based direct estimates of stand height and forest canopy cover. The reference biomass and volume were predicted from lidar metrics. Landsat time series predictors included annual temporal profiles of band reflectance and vegetation indices for the 1985-2023 period. Additional predictor variables including synthetic aperture radar, disturbance history, topography and forest type were also evaluated to optimize forest structural attributes retrieval. The estimates were independently validated at two temporal scales, i) the year of model calibration and ii) the year of the second lidar survey. The final models used as predictor variables only Landsat based metrics and topographic information, as the available SAR time-series were relatively short (1991-2011) and disturbance information did not decrease the estimation error. Model accuracies were higher in the Mediterranean forests when compared to the temperate forests (R2 = 0.6-0.8 vs. 0.4-0.5). Between the first (1985-1989) and the last (2020-2023) decades of the monitoring period the average forest cover increased from 21 ± 2% to 32 ± 1%, mean height increased from 6.6 ± 0.43 m to 7.9 ± 0.18 m and the mean biomass from 31.9 ± 3.6 t ha-1 to 50.4 ± 1 t ha-1 for the Mediterranean forests. In temperate forests, the average canopy cover increased from 55 ± 4% to 59 ± 3%, mean height increased from 15.8 ± 0.77 m to 17.3 ± 0.21m, while the growing stock volume increased from 137.8 ± 8.2 to 151.5 ± 3.8 m3 ha-1. Our results suggest that multispectral data can be successfully linked with lidar to provide continuous information on forest height, cover, and biomass trends.


Asunto(s)
Biomasa , Monitoreo del Ambiente , Bosques , España , Monitoreo del Ambiente/métodos , Tecnología de Sensores Remotos , Árboles/crecimiento & desarrollo
3.
Aesthet Surg J ; 39(1): 83-93, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29726916

RESUMEN

Background: Increasingly, women have sought alternatives to traditional options (lubricants, estrogen products, and hormone replacement therapy) for unwelcome vaginal changes of menopause. Objectives: This study evaluated whether a series of three monthly fractional CO2 laser treatments significantly improves and maintains vaginal health indices of elasticity, fluid volume, pH level, epithelial integrity, and moisture. Self-reported symptoms of vaginal atrophy were also measured. Biopsy samples after a series of three treatments were evaluated for histological changes to vaginal canal tissue. Methods: Forty postmenopausal women were treated extravaginally and internally with a fractional CO2 laser. Objective measurements of vaginal health index, as well as subjective measurements of symptoms of vulvovaginal atrophy (VVA), urinary incontinence, and sexual function were reported at baseline. Follow-up evaluations were at one, three, six, and 12 months after the third treatment. Results: Vaginal health index improved significantly after the first treatment and was maintained with mean improvement of 9.6 ± 3.3 (P < 0.001) and 9.5 ± 3.3 (P < 0.001) at the 6- and 12-month follow ups, respectively. Vaginal symptoms of dryness, itching, and dyspareunia improved significantly (P < 0.05) at all evaluations. Histological findings showed increased collagen and elastin staining, as well as a thicker epithelium with an increased number of cell layers and a better degree of surface maturation. Conclusions: Fractional CO2 laser treatments were well tolerated and were associated with improvement in vaginal health and amelioration of symptoms of VVA. Histological changes in the epithelium and lamina propria, caused by fractional CO2 laser treatments, correlated with clinical restoration of vaginal hydration and pH to premenopausal levels.


Asunto(s)
Láseres de Gas/uso terapéutico , Terapia por Luz de Baja Intensidad/instrumentación , Posmenopausia/fisiología , Enfermedades Vaginales/radioterapia , Enfermedades de la Vulva/radioterapia , Adulto , Anciano , Atrofia/fisiopatología , Atrofia/cirugía , Biopsia , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Terapia por Luz de Baja Intensidad/métodos , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Vagina/patología , Vagina/efectos de la radiación , Enfermedades Vaginales/patología , Enfermedades Vaginales/fisiopatología , Vulva/patología , Vulva/efectos de la radiación , Enfermedades de la Vulva/patología , Enfermedades de la Vulva/fisiopatología
4.
Opt Express ; 23(17): 22238-49, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26368196

RESUMEN

We present a theoretical study of the Faraday effect in hybrid magneto-plasmonic crystals that consist of Au-Co-Au perforated membranes with a periodic array of sub-wavelength holes. We show that in these hybrid systems the interplay between the extraordinary optical transmission and the magneto-optical activity leads to a resonant enhancement of the Faraday rotation, as compared to purely ferromagnetic membranes. In particular, we determine the geometrical parameters for which this enhancement is optimized and show that the inclusion of a noble metal like Au dramatically increases the Faraday rotation over a broad bandwidth. Moreover, we show that the analysis of the Faraday rotation in these periodically perforated membranes provides a further insight into the origin of the extraordinary optical transmission.

5.
Opt Express ; 23(22): 28108-18, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26561082

RESUMEN

Plasmonic antennas integrated on silicon devices have large and yet unexplored potential for controlling and routing light signals. Here, we present theoretical calculations of a hybrid silicon-metallic system in which a single gold nanoantenna embedded in a single-mode silicon waveguide acts as a resonance-driven filter. As a consequence of scattering and interference, when the resonance condition of the antenna is met, the transmission drops by 85% in the resonant frequency band. Firstly, we study analytically the interaction between the propagating mode and the antenna by including radiative corrections to the scattering process and the polarization of the waveguide walls. Secondly, we find the configuration of maximum interaction and numerically simulate a realistic nanoantenna in a silicon waveguide. The numerical calculations show a large suppression of transmission and three times more scattering than absorption, consequent with the analytical model. The system we propose can be easily fabricated by standard silicon and plasmonic lithographic methods, making it promising as real component in future optoelectronic circuits.

6.
Exp Appl Acarol ; 65(1): 107-24, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25183388

RESUMEN

Ticks are sensitive to changes in relative humidity and saturation deficit at the microclimate scale. Trends and changes in rainfall are commonly used as descriptors of field observations of tick populations, to capture the climate niche of ticks or to predict the climate suitability for ticks under future climate scenarios. We evaluated daily and monthly relationships between rainfall, relative humidity and saturation deficit over different ecosystems in Europe using daily climate values from 177 stations over a period of 10 years. We demonstrate that rainfall is poorly correlated with both relative humidity and saturation deficit in any of the ecological domains studied. We conclude that the amount of rainfall recorded in 1 day does not correlate with the values of humidity or saturation deficit recorded 24 h later: rainfall is not an adequate surrogate for evaluating the physiological processes of ticks at regional scales. We compared the Normalized Difference Vegetation Index (NDVI), a descriptor of photosynthetic activity, at a spatial resolution of 0.05°, with monthly averages of relative humidity and saturation deficit and also determined a lack of significant correlation. With the limitations of spatial scale and habitat coverage of this study, we suggest that the rainfall or NDVI cannot replace relative humidity or saturation deficit as descriptors of tick processes.


Asunto(s)
Clima , Ecosistema , Monitoreo del Ambiente/métodos , Lluvia , Garrapatas/fisiología , Agua , Animales , Europa (Continente) , Océanos y Mares , Plantas , Nave Espacial
7.
Osteoporos Int ; 25(2): 645-51, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23903956

RESUMEN

UNLABELLED: The role of sclerostin on bone metabolism and its relation to sex steroids in patients with prostate cancer (PC) is not well known. We found that sclerostin levels are significantly increased in PC patients, particularly in those with androgen deprivation therapy (ADT), and there is an inverse relationship between sclerostin levels and testosterone. INTRODUCTION: Recent studies have evaluated sclerostin levels in bone diseases as osteoporosis. However, there are few data in PC patients, particularly in patients with hypogonadism related to ADT. The aim of the present study was to compare serum sclerostin levels in ADT/non-ADT-treated PC patients and healthy controls and to evaluate their relationship with sex steroids and bone metabolism. METHODS: We performed a cross-sectional study involving 81 subjects: 25 ADT-treated PC patients, 34 PC patients without ADT treatment, and 22 healthy controls. We measured serum sclerostin levels, bone turnover markers, bone mineral density (BMD) in all individuals, and sex steroids levels in PC patients. RESULTS: Serum sclerostin levels were significantly higher in PC patients compared to those in control subjects. ADT-treated patients had significantly higher sclerostin levels than PC patients without ADT treatment: ADT 64.52 ± 27.21 pmol/L, non-ADT 48.24 ± 15.93 pmol/L, healthy controls 38.48 ± 9.19 pmol/L, p < 0.05. In PC patients, we found a negative relationship between serum sclerostin levels and androgens after age adjustment (total testosterone: r = -0.309, p = 0.029; bioavailable testosterone: r = -0.280, p = 0.049; free testosterone: r = -0.299, p = 0.035). We did not observe any relationship between sclerostin levels and bone turnover markers or BMD in any group. CONCLUSIONS: Circulating sclerostin levels are significantly increased in patients with PC and particularly in those receiving ADT. The inverse relationship between serum sclerostin and testosterone in these patients suggests that androgens are key regulators of bone metabolism in this population.


Asunto(s)
Proteínas Morfogenéticas Óseas/sangre , Neoplasias de la Próstata/sangre , Testosterona/sangre , Proteínas Adaptadoras Transductoras de Señales , Anciano , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos Hormonales/uso terapéutico , Densidad Ósea/fisiología , Remodelación Ósea/fisiología , Estudios de Casos y Controles , Estudios Transversales , Estradiol/sangre , Marcadores Genéticos , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/fisiopatología
8.
Cir Pediatr ; 27(4): 183-8, 2014 Oct.
Artículo en Español | MEDLINE | ID: mdl-26065111

RESUMEN

INTRODUCTION: Children have much lower incidence of pressure sores (PS) than adults and furthermore, they are diagnosed in earlier stages. Therefore, the reported experience with surgical treatment of advanced pediatric PS is scarce. MATERIAL AND METHODS: We present the surgical treatment of 2 chronic PS stage IV in children aged 11 and 14 years, by means of perforator flaps based on the gluteal arteries: in the first case we used a free-style flap based on a left medial gluteal perforator and in the second a large reusable rotation-advancement flap based on both right superior and inferior gluteal artery perforators. RESULTS: In both patients we achieved a rapid cure with 100% survival of the flaps and a stable cover over a 6 month and 1 year follow-up respectively. CONCLUSIONS: Gluteal artery perforator flaps can produce excellent and durable results in the reconstructive treatment of sacral pressure sores in children. These flaps carry lower morbidity than musculocutaneous flaps and are more reliable than traditional fasciocutaneous flaps. Furthermore they preserve more reconstructive options in case of recurrence during the children's lifetime.


Asunto(s)
Colgajo Perforante , Procedimientos de Cirugía Plástica/métodos , Úlcera por Presión/cirugía , Adolescente , Nalgas/irrigación sanguínea , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Colgajo Perforante/irrigación sanguínea , Úlcera por Presión/patología , Resultado del Tratamiento
9.
Rev Esp Quimioter ; 37(2): 163-169, 2024 Apr.
Artículo en Español | MEDLINE | ID: mdl-38372121

RESUMEN

OBJECTIVE: Antimicrobial stewardship programs (ASP) have become a key tool in the adaptation of these drugs to the health system. The information available on the application and indicators used in these programs in emergency departments is scarce. The objective of this study is to know the extent of ASP implementation in the emergency departments, as well as the use of antimicrobials in these units. METHODS: Multicenter retrospective study. An invitation was sent to all participants of the REDFASTER-SEFH emergency pharmacist working group. A questionnaire was used consisting of 21 items, answered by a team made up of a pharmacist, emergency room specialist, infectious disease specialist and microbiologist. RESULTS: Eighteen hospitals completed the survey. Fourteen (77.8%) had an ASP manager. The DDD value per 1000 admissions ranged between 36.5 and 400.5 (median: 100.4 [IQR:57.2-157.3]). Both carbapenem and macrolide group presented wide variability in use. Six (33.3%) hospitals had an annual report on the specific resistance profile for urine and blood cultures. The percentage of multi-drug resistant strains in urine cultures was 12.5% and in blood cultures 12.2%. The percentage of adequacy in the bacteremia treatment was 81.0% (IQR:74.6-85.0%), while in urinary tract infections was 78.0% (IQR:71.5-88.0). CONCLUSIONS: Despite the existence of ASP members in emergency services, as well as the training activity and local guidelines is common. knowledge of the use of antimicrobials and resistances is limited. Future activities must be aimed at improving information about the ASP results in these units.


Asunto(s)
Antiinfecciosos , Programas de Optimización del Uso de los Antimicrobianos , Humanos , Estudios Retrospectivos , Antiinfecciosos/uso terapéutico , Antibacterianos/uso terapéutico , Hospitales
10.
Opt Express ; 21(22): 27356-70, 2013 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-24216958

RESUMEN

We show that the interaction between a plasmonic and a magnetoplasmonic metallic nanodisk leads to the appearance of magneto-optical activity in the purely plasmonic disk induced by the magnetoplasmonic one. Moreover, at specific wavelengths the interaction cancels the net electromagnetic field at the magnetoplasmonic component, strongly reducing the magneto-optical activity of the whole system. The MO activity has a characteristic Fano spectral shape, and the resulting MO inhibition constitutes the magneto-optical counterpart of the electromagnetic induced transparency.

11.
Osteoporos Int ; 24(2): 713-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22588185

RESUMEN

SUMMARY: Fractures are increased among prostate cancer patients. No data have been reported in patients with prostate cancer about the relation between serum sex hormone-binding globulin (SHBG) and bone metabolism. We found that SHBG levels were inversely related to bone mass and vertebral fractures in this population. INTRODUCTION: Fractures are increased among prostate cancer patients, especially those on androgen deprivation therapy (ADT), but few data are available on the role of SHBG in their bone status. Our objective was to analyze the relation between serum SHBG and bone metabolism in prostate cancer patients. METHODS: This is a cross-sectional study including 91 subjects with prostate cancer (54 % with ADT). We measured serum levels of SHBG and sex steroids, bone mineral density (BMD) by dual-energy X-ray absorptiometry, and prevalent radiographic vertebral fractures. RESULTS: SHBG levels were inversely related to BMD (femoral neck: r = -0.299, p = 0.00; total hip: r = -0.259, p = 0.019). Subjects with osteoporosis had higher SHBG concentrations than patients without osteoporosis (60.97 ± 39.56 vs 44.45 ± 23.32 nmol/l, p = 0.022). Patients with SHBG levels in the first quartile (>57.6 nmol/l) had an odds ratio (OR) for osteoporosis of 2.59 (95 % CI, 1.30-5.12; p = 0.009) compared with patients with lower SHBG levels. In patients with SHBG >57.6 nmol/l, the OR for vertebral fractures was 2.34 (95 % CI, 1.15-4.78; p = 0.034). The calculated OR was higher after adjustment for age (OR, 5.16; 95 % CI, 1.09-24.49; p = 0.039), estrogens (OR, 6.45; 95 % CI, 1.44-28.95; p = 0.023), and androgens (OR, 5.51; 95 % CI, 1.36-22.37; p = 0.017). CONCLUSIONS: In prostate cancer patients, SHBG levels were inversely related to bone mass and vertebral fractures. Determination of the serum SHBG level may constitute a useful and straightforward marker for predicting the severity of osteoporosis in these patients.


Asunto(s)
Osteoporosis/etiología , Neoplasias de la Próstata/complicaciones , Globulina de Unión a Hormona Sexual/análisis , Fracturas de la Columna Vertebral/etiología , Absorciometría de Fotón , Anciano , Antagonistas de Andrógenos/efectos adversos , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Biomarcadores/sangre , Densidad Ósea/fisiología , Estudios Transversales , Cuello Femoral/fisiopatología , Hormonas Esteroides Gonadales/sangre , Hormona Liberadora de Gonadotropina/agonistas , Articulación de la Cadera/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/sangre , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/sangre , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/fisiopatología , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Fracturas de la Columna Vertebral/sangre , Fracturas de la Columna Vertebral/fisiopatología
12.
J Endocrinol Invest ; 36(1): 16-20, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22391059

RESUMEN

BACKGROUND: The role of osteoprotegerin (OPG) as a marker of cardiovascular disease (CVD) in Type 2 diabetes (T2DM) is not well established. Moreover, the relationship between OPG, osteoporosis, and vertebral fractures in T2DM remains to be elucidated. AIM: To determine the role of serum OPG in the prediction of CVD and bone disease in T2DM males. SUBJECTS AND METHODS: Cross-sectional study with 68 males, 43 with T2DM and 25 subjects without diabetes. We measured: serum OPG by inmunoassay, the presence of CVD (coronary heart disease, cerebrovascular and peripheral artery disease), surrogate markers of CVD [intima- media thickness (IMT) and aortic calcification] and bone disease (bone mineral density and prevalent vertebral fractures). RESULTS: OPG serum levels (in pmol/l) were significantly higher in T2DM males with abnormal IMT (5.12 ± 1.59 vs 3.76 ± 1.98), carotid plaque (5.46 ± 1.67 vs 4.20 ± 1.81), aortic calcification (5.91 ± 1.39 vs 4.07 ± 1.76), hypertension (5.11 ± 1.86 vs 3.81 ± 1.47), and peripheral artery disease (6.24 ± 1.64 vs 4.21 ± 1.63, p < 0.05 for all comparisons). In the logistic regression analysis (after adjustment for age and main cardiovascular risk factors), serum OPG (per 1 pmol/l increase in OPG) was associated with increased risk of abnormal IMT [odds ratio (OR) 1.84, confidence interval (CI) 1.21-2.79, p = 0.004), carotid plaque (OR 1.71, CI 1.13-2.58, p = 0.012), aortic calcification (OR 2.21, CI 1.27-3.84, p = 0.05) and peripheral artery disease (OR 4.02, CI 1.65-9.8 p = 0.002). However, OPG were not related to bone mass or vertebral fractures. CONCLUSIONS: Our results suggest that in T2DM males OPG serum concentrations constitute a marker of CVD, but not a marker of bone disease.


Asunto(s)
Biomarcadores/sangre , Enfermedades Óseas/diagnóstico , Enfermedades Cardiovasculares/diagnóstico , Grosor Intima-Media Carotídeo , Complicaciones de la Diabetes/diagnóstico , Diabetes Mellitus Tipo 2/sangre , Osteoprotegerina/sangre , Absorciometría de Fotón , Determinación de la Presión Sanguínea , Densidad Ósea , Enfermedades Óseas/sangre , Enfermedades Óseas/etiología , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Estudios Transversales , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/etiología , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo
13.
Langmuir ; 28(24): 9127-30, 2012 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-22667989

RESUMEN

The magneto-optical properties of Au-Co(x)Fe(3 - x)O(4) core-shell nanowires embedded in porous alumina membranes are studied. The structures were obtained by depositing Co(x)Fe(3 - x)O(4) on the pore walls of alumina membranes by atomic layer deposition and filling the resulting nanotube with gold by electrodeposition. The effect of plasmon resonance excitation on the magneto-optical activity is clearly observed as a modification of the spectral line shape of the Kerr rotation signal.

14.
Opt Express ; 18(4): 3556-67, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-20389364

RESUMEN

Radiative corrections to the polarizability tensor of isotropic particles are fundamental to understand the energy balance between absorption and scattering processes. Equivalent radiative corrections for anisotropic particles are not well known. Assuming that the polarization within the particle is uniform, we derived a closed-form expression for the polarizability tensor which includes radiative corrections. In the absence of absorption, this expression of the polarizability tensor is consistent with the optical theorem. An analogous result for infinitely long cylinders was also derived. Magneto optical Kerr effects in non-absorbing nanoparticles with magneto-optical activity arise as a consequence of radiative corrections to the electrostatic polarizability tensor.


Asunto(s)
Modelos Teóricos , Radiometría , Anisotropía , Simulación por Computador , Impedancia Eléctrica , Campos Electromagnéticos , Tamaño de la Partícula , Dosis de Radiación , Dispersión de Radiación
15.
Phys Rev Lett ; 104(14): 147401, 2010 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-20481960

RESUMEN

In this Letter we show that nanostructures made out of pure noble metals can exhibit measurable magneto-optic activity at low magnetic fields. This phenomenon occurs when the localized surface plasmon resonance of the nanostructure is excited in the presence of a static magnetic field parallel to the propagation of incident light. The large magneto-optical response observed comes from an increase of the magnetic Lorentz force induced by the large collective movement of the conduction electrons in the nanostructures when the resonance is excited.

16.
Zoonoses Public Health ; 63(1): 40-52, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25965508

RESUMEN

All active stages of the tick Ixodes ricinus were collected monthly at two sites in northern Spain between the years 2000 and 2007. We used percentile accumulation of the active stage in the environment to evaluate simple and coherent correlations between accumulation of the active stages of larvae and nymphs and medium-resolution MODIS satellite-derived information on the climate, including monthly and accumulated temperature and the Normalized Difference Vegetation Index (NDVI). This framework is not intended to predict the actual abundance of ticks in the field as a measure of the hazard to humans, but to provide a basic structure for addressing the phenology of the tick in its geographic range. We demonstrated that the accumulation of larval ticks in the active stage is a sigmoid function of the accumulated temperature from the beginning of the calendar year. We also demonstrated that the accumulated temperature necessary to recruit nymphs from the questing larval stage is a function of the changes in accumulated larvae and nymphs and the accumulated temperature and NDVI recorded by the Aqua sensor. The low p-values obtained in the regressions confirmed that such recruitment can be calculated using time intervals to estimate, for example, the beginning of the questing period or the time of the year when a population peak can be expected. The comparison among predicted and actual accumulated temperatures between larvae and nymph recruitment had an averaged error of ±20 days in one complete year. The use of accumulated temperature and NDVI proposed in this study opens up the re-evaluation of reports on the phenology of the tick in Europe. This framework is intended to evaluate the same correlations along the tick's range and predict its phenological patterns in areas of pathogen transmission risk for humans.


Asunto(s)
Ixodes/fisiología , Animales , Clima , Ecosistema , Ambiente , Humanos , Ixodes/crecimiento & desarrollo , Estadios del Ciclo de Vida , Dinámica Poblacional , Análisis de Regresión , Estaciones del Año , España , Temperatura
17.
Sci Rep ; 6: 30803, 2016 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-27488903

RESUMEN

The magneto-optical activity, namely the polarization conversion capabilities of high-index, non-absorbing, core-shell dielectric nanospheres is theoretically analyzed. We show that, in analogy with their plasmonic counterparts, the polarization conversion in resonant dielectric particles is linked to the amount of electromagnetic field probing the magneto-optical material in the system. However, in strong contrast with plasmon nanoparticles, due to the peculiar distribution of the internal fields in resonant dielectric spheres, the magneto-optical response is fully governed by the magnetic (dipolar and quadrupolar) resonances with little effect of the electric ones.

18.
J Phys Condens Matter ; 28(13): 135101, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-26940756

RESUMEN

Self-diffusion and radial distribution functions are studied in a strongly confined Lennard-Jones fluid. Surprisingly, in the solid-liquid phase transition region, where the system exhibits dynamic coexistence, the self-diffusion constants are shown to present up to three-fold variations from solid to liquid phases at fixed temperature, while the radial distribution function corresponding to both the liquid and the solid phases are essentially indistinguishable.

20.
Hum Immunol ; 62(9): 901-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11543892

RESUMEN

Twenty alleles for the locus human leukocyte antigen (HLA-A) and 46 for the HLA-B locus were detected in Jordanians. This indicates the existence of high polymorphism in this area. The most frequent HLA class I alleles found were A*0201 (0.1344), B*0713 (0.1724), and C*0502 (0.1793). Twenty-six different alleles in the Jordanian population were identified for the DRB1 locus being the DRB1*0704 (0.2552), DRB1*0401 (0.1965), and DRB1*1501 (0.0896) the most frequent. Common DQA1 alleles were DQA1*0201 (0.2690), DQA1*0301 (0.2414), and DQA1*0501 (0.1724). Three-loci haplotype heterogeneity was common: 38 HLA class II haplotypes were identified, of which the most frequently observed was DRB1*0401-DQA1*0301-DQB1*0302 (0.1793). In addition, as expected, 220 different five-loci haplotypes with several unusual allelic combinations were observed, although many of them are pan-European haplotypes. The most frequent five-loci haplotype was the A30-B7-DRB1*03-DQA1*0501-DQB1*0201 (0.0138). It seems that the specific Jordanian haplotypes are the following: the A31-B7-DRB1*04/07-DQA1*0301/0201-DQB1*0302/0202 haplotypes (0.0103) and the A1-B7-DRB1*07-DQA1*0201-DQB1*0202, A2-B7-DRB1*04-DQA1*0301-DQB1*0302, A11-B7-DRB1*07-DQA1*0201-DQB1*0201 haplotypes but at lower frequencies (0.007). A tree analysis of HLA class I and class II alleles were made for several Caucasian populations and individual genetic distances calculated. The haplotype frequencies, genetic distances, and dendrograms do not reveal great differences as compared with those in other Mediterranean countries and Western Europeans populations. Our results suggest that both HLA class I and class II polymorphism (but especially the former) of the Jordanian population demonstrates considerable heterogeneity, which reflects ancient and recent admixture with neighboring populations, and important human migratory trends throughout the history.


Asunto(s)
Alelos , Frecuencia de los Genes/genética , Genes MHC Clase II/genética , Genes MHC Clase I/genética , Antígenos HLA/genética , Haplotipos/genética , Polimorfismo Genético , Adulto , Europa (Continente) , Femenino , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Antígenos HLA-DQ/genética , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Jordania , Masculino , Filogenia , Reacción en Cadena de la Polimerasa
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