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1.
ACS Appl Mater Interfaces ; 16(38): 51274-51282, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39285705

RESUMEN

Artificial intelligence and human-computer interaction advances demand bioinspired sensing modalities capable of comprehending human affective states and speech. However, endowing skin-like interfaces with such intricate perception abilities remains challenging. Here, we have developed a flexible piezoresistive artificial ear (AE) sensor based on gold nanoparticles, which can convert sound signals into electrical signals through changes in resistance. By testing the sensor's performance at both frequency and sound pressure level (SPL), the AE has a frequency response range of 20 Hz to 12 kHz and can sense sound signals from up to 5 m away at a frequency of 1 kHz and an SPL of 126 dB. Furthermore, through deep learning, the device achieves up to 96.9% and 95.0% accuracy in classification and recognition applications for seven emotional and eight urban environmental noises, respectively. Hence, on one hand, our device can monitor the patient's emotional state by their speech, such as sudden yelling and screaming, which can help healthcare workers understand patients' condition in time. On the other hand, the device could also be used for real-time monitoring of noise levels in aircraft, ships, factories, and other high-decibel equipment and environments.


Asunto(s)
Aprendizaje Profundo , Emociones , Oro , Humanos , Emociones/fisiología , Oro/química , Nanopartículas del Metal/química , Voz
2.
Breast Cancer Res Treat ; 204(3): 531-538, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38194133

RESUMEN

PURPOSE: Despite limited evidence supporting its effectiveness, most guidelines recommend long-term, routinely scheduled in-person surveillance of patients with early breast cancer (EBC). The COVID-19 pandemic led to increased use of virtual care. This survey evaluated patient perspectives on follow-up care. METHODS: Patients with EBC undergoing surveillance were surveyed about follow-up protocols, perceptions, and interest in clinical trials assessing different follow-up strategies. RESULTS: Of 402 approached patients 270 completed the survey (response rate 67%). Median age 62.5 years (range 25-86) and median time since breast cancer diagnosis was 3.8 years (range < 1-33 years). Most (n = 148/244, 60%) were followed by more than one provider. Routine follow-ups with breast examination were mostly conducted by medical/radiation oncologists every 6 months (n = 110/236, 46%) or annually (n = 106/236, 44%). Participants felt routine follow-up was useful to monitor for recurrence, manage side effects of cancer treatment and to provide support/reassurance. Most participants felt regular follow-up care would detect recurrent cancer earlier (n = 214/255, 96%) and increase survival (n = 218/249, 88%). The COVID-19 pandemic reduced the number of in-person visits for 54% of patients (n = 63/117). Patients were concerned this reduction of in-person visits would lead to later detection of both local (n = 29/63, 46%) and distant recurrences (n = 25/63, 40%). While many felt their medical and radiation oncologists were the most suited to provide follow-up care, 55% felt comfortable having their primary care provider (PCP) conduct surveillance. When presented with a scenario where follow-up has no effect on earlier detection or survival, 70% of patients still wanted routine in-person follow-up for reassurance (63%) with the goal of earlier recurrence detection (56%). CONCLUSIONS: Despite limited evidence of effectiveness of routine in-person assessment, patients continue to place importance on regularly scheduled in-person follow-up.


Asunto(s)
Neoplasias de la Mama , COVID-19 , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Estudios de Seguimiento , Pandemias , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/diagnóstico , COVID-19/epidemiología
3.
Langmuir ; 40(1): 950-959, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38110298

RESUMEN

Frost formation and accumulation can have catastrophic effects on a wide range of industrial activities. Hence, a dual-scale surface with a stable Cassie-Baxter state is developed to mitigate the frosting problem by utilizing direct laser interference lithography assisted with hydrothermal treatment. The high Laplace pressure tolerance under the evaporation stimulus and prolonged Cassie-Baxter state maintenance under the condensation stimulus demonstrate the stable Cassie-Baxter state. The dual-scale surface exhibits a lengthy frost-delaying time of up to 5277 s at -7 °C due to the stable Cassie-Baxter state. The self-removal of frost is achieved by promoting the mobility of frost melts driven by the released interfacial energy. In addition, the dense flocculent frost layer is observed on the single-scale micro surface, whereas the sparse pearl-shaped frost layer with many voids is obtained on the dual-scale surface. This work will aid in understanding the frosting process on various-scale superhydrophobic surfaces and in the design of antifrosting surfaces.

4.
Foods ; 12(12)2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37372639

RESUMEN

Global levels of biodiversity and dietary diversity are decreasing, leading to food and nutrition insecurity. This is partially due to the homogenization of the global food supply with commodity crops. The reintroduction or introduction of neglected and underutilized species, minor, forgotten, and indigenous crops and landrace varieties to the wider food systems and further diversification have been outlined as the future strategies for tackling the above by the United Nations and the Food and Agriculture Organization in their policy frameworks. Most of the above species/crops are marginalized and only used across local food systems and in research. With over 15,000 different seed banks and repositories worldwide, information transparency and communication are crucial for database searching and their effective utilization. Much confusion persists around the true nature of those plants, and this prohibits the efficient utilization of their economic potential. A linguistic corpus search and a systematic literature review were conducted using the six most popular collocates to the above terms, which were as follows: ancient, heirloom, heritage, traditional, orphan, and the more distinct term 'landrace'. The results were interpreted using the Critical Discourse Analysis method. The definitions' findings show that heirloom, heritage, and ancient are mainly used in the United Kingdom and USA, where they are used to describe 'naturalized' and 'indigenized' or 'indigenous' food crops with a strong affiliation to 'family' and the 'act of passing seeds down from generation to generation'. Orphan crops, on the other hand, are often described as being 'overlooked' by growers and 'underfunded' by researchers. Landrace is most strongly affiliated with 'locality', 'biocultural diversity', and 'indigenous', and with genomics literature, where the characteristics are often discussed in the context of genetics and population biology. Contextualizing, most of the terms were found to be 'arbitrary' and 'undefinable' due to their continuing evolution in the socially accepted form of language, perhaps apart from landrace. The review has retrieved 58 definitions for the mentioned 6 terms, together with the primary key terms creating a tool to facilitate a better inter-sector communication and aid in policy.

5.
J Opt Soc Am A Opt Image Sci Vis ; 39(12): 2398-2409, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36520763

RESUMEN

The polarization perception sensitivity of the human eyes affects the perceived polarized image quality. In this paper, we used polarized spatiotemporal structured images to develop a spatiotemporal age mapping of the polarization perception of human eyes. We built an optical modulation transfer function mathematical model of the aging human eyes with spatiotemporal frequency domains and introduced the Stokes vector to analyze the polarized images. The proposed model provides a testing method based on a set of polarization images with spatiotemporal frequencies varying according to the perception of differently aged viewers. Then, we experimentally validated the proposed model by performing polarization perception tests on a group of volunteers. The test method has the diagnostic potential to confirm the health of human eyes and identify potential age-related macular diseases.


Asunto(s)
Degeneración Macular , Visión Ocular , Humanos , Anciano , Modelos Teóricos , Ojo , Envejecimiento
6.
J Phys Chem A ; 126(21): 3358-3372, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35587993

RESUMEN

Modeling the complex chemical phenomena resulting from multiple active species and long-chain polymers is limited by uncertainties in the reaction rate parameters, which increase rapidly with the number of active species and/or reaction pathways. Reactive molecular dynamics simulations have the potential to help obtain in-depth information on the chemical reactions that occur between the polymer (e.g., ablative material) and the multiple active species in an aggressive environment. In this work, we demonstrate that molecular dynamics (MD) simulations using the ReaxFF interatomic potential can be used to obtain the reaction kinetics of complex reaction pathways at high temperatures. We report two recently developed tools, namely, MolfrACT and KinACT, designed to extract chemical kinetic pathways by postprocessing reactive MD simulation data. The pathway extraction is based on a new algorithm, Consistent Reaction Stoichiometry via an Iterative Scheme (CReSIS), for the automated extraction of reactions and kinetics from MD trajectories. As a validation of the methodology, we first report the kinetic analysis and mechanisms for the high-temperature combustion of iso-octane. The observed reaction pathways are consistent with experimental models. In addition, we compare the activation energies of select iso-octane combustion pathways with experimental data and show that nanosecond timescale molecular dynamics simulations are sufficient to obtain realistic estimates of activation energies for different fuel consumption reaction pathways at high temperatures. The framework developed here can potentially be combined with time-series forecasting and machine learning methods to further reduce the computational complexity of transient molecular dynamics simulations, yet yielding realistic chemical kinetics information. Subsequently, the CReSIS scheme applied to ethylene-propylene-diene-monomer (EPDM) rubber ablative reveals that H2O, C2H4, and HCHO are the major products during the initial stages of the polymer degradation in high-temperature oxidative environments. While prior work involving ReaxFF simulations is restricted to overall rates of formation of any species, we extract kinetic information for individual reaction pathways. In this paper, we present several reaction pathways observed during the EPDM rubber degradation into the dominant products and report the pathway-specific reaction rates. Arrhenius analysis reveals that the dominant reaction pathway activation energies for the formation of water, ethylene, and formaldehyde are 34.42, 27.26, and 6.37 kcal/mol, respectively. In contrast, the activation energies for the overall formation (across all reaction pathways) of these products are in the 40-50 kcal/mol range.

7.
J Forensic Leg Med ; 79: 102108, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33896596

RESUMEN

Studies investigating the differential decomposition of remains on different surfaces have been limited to qualitative data. This study statistically analyses the differences in rate and pattern of decomposition between concrete, gravel and grass surfaces. A total of 11 pigs (Sus scrofa domesticus) were used in the study: three for the concrete and gravel surfaces each, and 5 for the grass surface. Results showed that there was no difference in the overall rate of decomposition between surfaces (p > 0.05); however, there were significant differences in the pattern of decomposition. Mummification was observed on all subjects in the study and may have been the reason for the similarities in the decomposition rates between surfaces. The results of this study show that in the intertwined relationship between factors affecting decomposition surface type may be overshadowed by other environmental factors.


Asunto(s)
Cambios Post Mortem , Propiedades de Superficie , Animales , Dípteros , Conducta Alimentaria , Entomología Forense , Patologia Forense , Poaceae , Porcinos
8.
J Forensic Leg Med ; 71: 101922, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32342901

RESUMEN

Plastic bag suffocation has been reported in cases of homicide, suicide, and accidental death, with an increase in numbers of suicide and accidental deaths. Though case reports are abundant, decomposition studies have not been performed. This study utilised 20 Sus scrofa domesticus to quantify the effect of a plastic bag covering the head on the rate and pattern of decomposition. A sample group of ten carcasses had plastic bags placed over the heads, with another ten carcasses acting as a control group, without a head covering. The carcasses were placed in an open field to decompose. Over the course of 52 days, data were collected bi-weekly on the rate and pattern of decomposition. The results show that a plastic bag covering the head of a carcass has an overall decreased effect on the rate of decomposition, compared to the control group. The decomposition pattern of head > trunk > limb in decreasing decomposition rate was not affected by the plastic bag; however, in comparison to the control group, the decomposition of the head and trunk regions differed significantly, while the limbs stayed unaffected. The heads of the sample group showed a decrease in decomposition rate, while the trunks showed an increase. This was deemed due to an increase in insect activity at the trunk and a decrease in activity at the head. An altered PMI calculation is provided.


Asunto(s)
Cabeza , Plásticos , Cambios Post Mortem , Animales , Asfixia , Estudios de Casos y Controles , Conducta Alimentaria , Entomología Forense , Patologia Forense , Larva , Modelos Animales , Estaciones del Año , Sus scrofa , Temperatura
9.
Clin Transl Radiat Oncol ; 16: 28-33, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30923751

RESUMEN

•This study reports on the prognostic ability of haematological parameters for the largest known biopsy-proven stage-I medically inoperable cohort treated with SBRT.•After SBRT, the median values of Hb, ALC, ANC and TPC declined whereas the NLR and the PLR increased as compared to pre-SBRT.•Anemia along with other parameters was found to be a poor prognostic factor for local control despite treatment with SBRT to doses of >100 Gy BED10.•Simple and minimally invasive methods like a peripheral blood sample can provide prognostic information even for stage-I NSCLC patients.•Patient, tumor and treatment factors along with molecular markers should be used to create risk stratification models that can guide therapy.

10.
Sci Rep ; 8(1): 11885, 2018 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-30089786

RESUMEN

Increases in the frequency of perturbations that drive coral community structure, such as severe thermal anomalies and high intensity storms, highlight the need to understand how coral communities recover following multiple disturbances. We describe the dynamics of cover and assemblage composition of corals on exposed inshore reefs in the Palm Islands, central Great Barrier Reef, over 19 years encapsulating major disturbance events such as the severe bleaching event in 1998 and Cyclone Yasi in 2011, along with other minor storm and heat stress events. Over this time, 47.8% of hard coral cover was lost, with a concomitant shift in coral assemblage composition due to taxon-specific rates of mortality during the disturbances, and asymmetric recovery in the aftermath thereof. High recruitment rates of some broadcast-spawning corals, particularly corymbose Acropora spp., even in the absence of adult colonies, indicate that a strong external larval supply replenished the stocks. Conversely, the time required for recovery of slow-growing coral morphologies and life histories was longer than the recurrence times of major disturbances. With interludes between bleaching and cyclones predicted to decrease, the probability of another severe disturbance event before coral cover and assemblage composition approximates historical levels suggests that reefs will continue to erode.


Asunto(s)
Antozoos/crecimiento & desarrollo , Antozoos/fisiología , Animales , Arrecifes de Coral , Tormentas Ciclónicas , Islas , Dinámica Poblacional , Estrés Fisiológico/fisiología
11.
J Forensic Sci ; 62(5): 1251-1258, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28168691

RESUMEN

This research investigated the sexual dimorphism of the first human rib using geometric morphometric and metric approaches on a sample of 285 specimens containing European Americans and African Americans from the Hamann-Todd collection. Metric measurements were investigated for sexual dimorphism and ancestral differences using univariate statistics. Four type II landmarks and 40 sliding semi-landmarks were placed outlining the dorsal and ventral curvatures of the ribs. Landmark data were processed using Generalized Procrustes Analyses with Procrustes distance sliding, and the subsequent coordinates were investigated for sexual dimorphism and ancestral differences using Procrustes ANOVAs. Both geometric morphometric and metric data were analyzed using cross-validated discriminant function analyses to test the hypothesis that variables from both approaches can be combined to increase sex classification rate. European Americans had sex correctly classified as high as 88.05% and African Americans as high as 70.86% using a combination of metric and geometric morphometric variables.


Asunto(s)
Costillas/anatomía & histología , Determinación del Sexo por el Esqueleto/métodos , Adulto , Negro o Afroamericano , Análisis Discriminante , Femenino , Antropología Forense , Humanos , Masculino , Análisis de Componente Principal , Población Blanca
12.
Clin Transl Radiat Oncol ; 5: 37-41, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29594215

RESUMEN

PURPOSE: In this single institution retrospective study of patients with stage I medically inoperable non-small cell lung cancer (NSCLC) treated with stereotactic ablative radiotherapy (SABR) we attempt to model overall survival (OS) using initial prognostic variables with specific attention on the Charlson co-morbidity index (CCI). METHODS: Between 2008 and 2013, 335 patients with medically inoperable stage I NSCLC were treated with SABR or hypofractionated radiotherapy (50-60 Gy in at least 5 Gy or 4 Gy fractions respectively) at our institution. Medical comorbidities and Charlson scores were determined by individual chart review. Patients were stratified into 3 groups based on the CCI score (0-1, 2-3, 4-9) and again based on the age-adjusted Charlson Comorbidity score (aCCI). Cumulative survival for each stratum was determined using the Kaplan-Meier method. Non-significant and confounding variables were identified and discounted from survival modeling. 3 sex stratified Cox regression models were tested: (1) aCCI with age and comorbidity combined; (2) age and CCI; (3) age alone, comorbidity removed. RESULTS: The median survival was 4.4 years and the median follow up 4.7 years. The median CCI and aCCI scores were 2 and 5 respectively. Patients with aCCI 7-12 had an increased hazard of death on univariate analysis HR 2.45 (1.15-5.22 95%CI, p = 0.02) and -excluding age as a competing variable- on multivariate analysis HR 2.25 (1.04-4.84 95%CI, p = 0.04). Patients with CCI 4-9 had an increased hazard of death on univariate analysis HR 1.57(1.30-2.90) but not on multivariate analysis. On formalized testing - with either continuous or categorical variables- all three survival models yielded similar coefficients of effect. CONCLUSION: We identify male gender, weight loss greater than 10% and age as independent prognostic factors for patients treated with medically inoperable NSCLC treated with SABR or hypofractionated radiotherapy. Based on our survival models, age alone can be used interchangeably with aCCI or CCI plus age with the same prognostic value. Age is more reliably recorded, less prone to error and therefore a more useful metric than Charlson score in this group of patients.

13.
J Chem Phys ; 143(8): 084701, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26328861

RESUMEN

In this work, we study diffusion of gases in porous amorphous carbon at high temperatures using equilibrium molecular dynamics simulations. Microporous and mesoporous carbon structures are computationally generated using liquid quench method and reactive force fields. Motivated by the need to understand high temperature diffusivity of light weight gases like H2, O2, H2O, and CO in amorphous carbon, we investigate the diffusion behavior as function of two important parameters: (a) the pore size and (b) the concentration of diffusing gases. The effect of pore size on diffusion is studied by employing multiple realizations of the amorphous carbon structures in microporous and mesoporous regimes, corresponding to densities of 1 g/cm(3) and 0.5 g/cm(3), respectively. A detailed analysis of the effect of gas concentration on diffusion in the context of these two porosity regimes is presented. For the microporous structure, we observe that predominantly, a high diffusivity results when the structure is highly anisotropic and contains wide channels between the pores. On the other hand, when the structure is highly homogeneous, significant molecule-wall scattering leads to a nearly concentration-independent behavior of diffusion (reminiscent of Knudsen diffusion). The mesoporous regime is similar in behavior to the highly diffusive microporous carbon case in that diffusion at high concentration is governed by gas-gas collisions (reminiscent of Fickian diffusion), which transitions to a Knudsen-like diffusion at lower concentration.

14.
Vision Res ; 115(Pt A): 48-57, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26291073

RESUMEN

This study explores both theoretically and experimentally the human perception of polarized light beyond that currently established. The radial analyser theory of Haidinger's phenomenon (HP) is used to predict the effect of observing visual stimuli comprising patterned zones characterized by orthogonal planes of linear polarization (linear polarization direction fields, LPD-fields). Any pattern can be represented as an LPD-field including optotypes and geometric forms. Simulated percepts differ from the original patterns although edges are mostly preserved. In edge-rich images a cross of attenuating contrast spanning the field of view is predicted. The mathematical model is verified experimentally using a liquid crystal display (LCD)-based polarization modulator imaged through a tangential (azimuthal) analyser with properties complementary to a radial analyser. The LCD device is then used in vivo to elicit perceptual responses in human subjects. Normal humans are found to readily detect spatially and temporally modulated isoluminant spatially-isochromatic, highly polarized LPD stimuli. Most subjects match the stimuli to corresponding images of theoretically predicted percepts. In particular edge perception and the presence of the contrast cross was confirmed. Unlike HP, static patterned LPD stimuli are perceived without difficulty. The simplest manifestation of human polarization perception is HP which is the fundamental element of an open set of stimulus-dependent percepts. This study demonstrates that humans have the ability to perceive and identify visual pattern stimuli defined solely by polarization state modulation.


Asunto(s)
Luz , Reconocimiento Visual de Modelos/fisiología , Adulto , Femenino , Humanos , Masculino , Matemática , Persona de Mediana Edad , Modelos Teóricos , Estimulación Luminosa/métodos , Adulto Joven
15.
J Forensic Sci ; 60(4): 1052-60, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26190264

RESUMEN

In homicide investigations, it is critically important that postmortem interval and postburial interval (PBI) of buried victims are determined accurately. However, clandestine graves can be difficult to locate; and the detection rates for a variety of search methods (ranging from simple ground probing through to remote imaging and near-surface geophysics) can be very low. In this study, simulated graves of homicide victims were emplaced in three sites with contrasting soil types, bedrock, and depositional environments. The long-term monthly in situ monitoring of grave soil water revealed rapid increases in conductivity up to 2 years after burial, with the longest study evidencing declining values to background levels after 4.25 years. Results were corrected for site temperatures and rainfall to produce generic models of fluid conductivity as a function of time. The research suggests soilwater conductivity can give reliable PBI estimates for clandestine burials and therefore be used as a grave detection method.

16.
J Forensic Sci ; 60(4): 979-82, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25823857

RESUMEN

Twenty Sus scrofa carcasses were used to study the effect the presence of clothing had on decomposition rate and colonization locations of Diptera species; 10 unclothed control carcasses were compared to 10 clothed experimental carcasses over 58 days. Data collection occurred at regular accumulated degree day intervals; the level of decomposition as Total Body Score (TBSsurf ), pattern of decomposition, and Diptera present was documented. Results indicated a statistically significant difference in the rate of decomposition, (t427  = 2.59, p = 0.010), with unclothed carcasses decomposing faster than clothed carcasses. However, the overall decomposition rates from each carcass group are too similar to separate when applying a 95% CI, which means that, although statistically significant, from a practical forensic point of view they are not sufficiently dissimilar as to warrant the application of different formulae to estimate the postmortem interval. Further results demonstrated clothing provided blow flies with additional colonization locations.


Asunto(s)
Vestuario , Dípteros/fisiología , Conducta Alimentaria , Cambios Post Mortem , Animales , Antropología Forense , Patologia Forense , Modelos Lineales , Sus scrofa
17.
Arch Virol ; 159(11): 3095-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24980395

RESUMEN

A multiplex reverse transcription polymerase chain reaction (RT-PCR) assay was developed for simultaneous detection of three orchid viruses: cymbidium mosaic virus (CymMV), odontoglossum ringspot virus (ORSV), and orchid fleck virus (OFV). Primers were used to amplify nucleocapsid protein gene fragments of 845 bp (ORSV), 505 bp (CymMV) and 160 bp (OFV). A 60-bp amplicon of plant glyceraldehyde-3-phophate dehydrogenase mRNA was included as an internal control against false negatives. The assay was validated against 31 collected plants from six orchid genera and compared with results obtained by transmission electron microscopy (TEM). The RT-PCR assay proved more sensitive than TEM for detection of OFV.


Asunto(s)
Reacción en Cadena de la Polimerasa Multiplex/métodos , Orchidaceae/virología , Enfermedades de las Plantas/virología , Potexvirus/aislamiento & purificación , Virus ARN/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Tobamovirus/aislamiento & purificación , Cartilla de ADN/genética , Potexvirus/clasificación , Potexvirus/genética , Virus ARN/clasificación , Virus ARN/genética , ARN Viral/genética , Tobamovirus/clasificación , Tobamovirus/genética
18.
PLoS One ; 8(6): e65363, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23755223

RESUMEN

Cyclone Yasi, one of the most severe tropical storms on record, crossed the central Great Barrier Reef (GBR) in February 2011, bringing wind speeds of up to 285 km hr⁻¹ and wave heights of at least 10 m, and causing massive destruction to exposed reefs in the Palm Island Group. Following the cyclone, mean (± S.E.) hard coral cover ranged from just 2.1 (0.2) % to 5.3 (0.4) % on exposed reefs and no reproductively mature colonies of any species of Acropora remained. Although no fragments of Acropora were found at impacted exposed sites following the cyclone, small juvenile colonies of Acropora (<10 cm diameter) were present, suggesting that their small size and compact morphologies enabled them to survive the cyclone. By contrast, sheltered reefs appeared to be unaffected by the cyclone. Mean (± S.E.) hard coral cover ranged from 18.2 (2.4) % to 30.0 (1.0) % and a large proportion of colonies of Acropora were reproductively mature. Macroalgae accounted for 8 to 16% of benthic cover at exposed sites impacted by cyclone Yasi but were absent at sheltered sites. Mean (± S.E.) recruitment of acroporids to settlement tiles declined from 25.3 (4.8) recruits tile⁻¹ in the pre-cyclone spawning event (2010) to 15.4 (2.2) recruits tile⁻¹ in the first post-cyclone spawning event (2011). Yet, post-cyclone recruitment did not differ between exposed (15.2±2.1 S.E.) and sheltered sites (15.6±2.2 S.E.), despite the loss of reproductive colonies at the exposed sites, indicating larval input from external sources. Spatial variation in impacts, the survival of small colonies, and larval replenishment to impacted reefs suggest that populations of Acropora have the potential to recover from this severe disturbance, provided that the Palm Islands are not impacted by acute disturbances or suffer additional chronic stressors in the near future.


Asunto(s)
Antozoos/fisiología , Arrecifes de Coral , Tormentas Ciclónicas , Desastres , Análisis de Varianza , Distribución Animal , Animales , Islas , Larva/fisiología , Densidad de Población , Queensland , Reproducción , Viento
19.
Appl Opt ; 50(34): H116-27, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22192996

RESUMEN

The space-bandwidth product (SBP) is a measure for the information capacity an optical system possesses. The two information processing steps in digital holography, recording, and reconstruction are analyzed with respect to the SBP. The recording setups for a Fresnel hologram, Fourier hologram, and image-plane hologram, which represent the most commonly used setup configurations in digital holography, are investigated. For the recording process, the required SBP to ensure the recording of the entire object information is calculated. This is accomplished by analyzing the recorded interference pattern in the hologram-plane. The paraxial diffraction model is used in order to simulate the light propagation from the object to hologram-plane. The SBP in the reconstruction process is represented by the product of the reconstructed field-of-view and spatial frequency bandwidth. The outcome of this analysis results in the best SBP adapted digital holographic setup.

20.
Appl Opt ; 50(24): 4711-9, 2011 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-21857692

RESUMEN

A novel (to our knowledge) approach for resolution improvement in digital holography is presented in this paper. The proposed method is based on recording the incoming interference field on a complementary metal-oxide semiconductor (CMOS) camera with subpixel resolution. The method takes advantage of the small pixel size of the CMOS sensor, while overcoming the reduced fill factor. This paper describes the experimental and numerical procedures. The improvement of the obtainable optical resolution, image quality, and phase measurement accuracy are demonstrated within this paper.

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