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1.
BMJ Mil Health ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38782492

RESUMEN

This paper describes the range of Defence Engagement (Health) (DE(H)) activities between Northern Ireland and Ireland following the Good Friday Agreement in April 1998. Although the Agreement made provision for cross-border cooperation in health, the Omagh bombing of August 1998 energised the discussion to provide greater co-ordination of future responses to mass casualty events. The paper describes these DE(H) activities at the Strategic, Operational and Tactical levels to show the integration across these levels and between the agencies of both governments. The paper shows how a DE(H) programme can have a successful strategic effect by finding topics of mutual interest that can bring together two countries in order to provide an effective health and social care provision. This paper forms part of a special issue of BMJ Military Health dedicated to Defence Engagement (.

2.
Nat Commun ; 13(1): 2959, 2022 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-35618737

RESUMEN

The capability of producing complex, high performance metal parts on demand has established laser powder bed fusion (LPBF) as a promising additive manufacturing technology, yet deeper understanding of the laser-material interaction is crucial to exploit the potential of the process. By simultaneous in-situ synchrotron x-ray and schlieren imaging, we probe directly the interconnected fluid dynamics of the vapour jet formed by the laser and the depression it produces in the melt pool. The combined imaging shows the formation of a stable plume over stable surface depressions, which becomes chaotic following transition to a full keyhole. We quantify process instability across several parameter sets by analysing keyhole and plume morphologies, and identify a previously unreported threshold of the energy input required for stable line scans. The effect of the powder layer and its impact on process stability is explored. These high-speed visualisations of the fluid mechanics governing LPBF enable us to identify unfavourable process dynamics associated with unwanted porosity, aiding the design of process windows at higher power and speed, and providing the potential for in-process monitoring of process stability.

3.
Sci Rep ; 10(1): 20261, 2020 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-33219260

RESUMEN

Endoluminal surgery for the treatment of colorectal neoplasia is typically carried out using electrocautery tools which imply limited precision and the risk of harm through collateral thermal damage to the adjacent healthy tissue. As a potential alternative, we present the successful colonic epithelial laser ablation by means of picosecond laser pulses. Laser ablation studies performed in ex-vivo colon tissue result in cavities with comparable thickness to early stage colorectal cancers. The corresponding histology sections exhibit only minimal collateral damage to the surrounding tissue and the depth of the ablation can be controlled precisely by means of the pulse energy. High-speed imaging has been used for the first time to visualize picosecond laser ablation of cancerous tissue in a clinically relevant model. This information was correlated with histopathology and optical surface profilometry revealing the dynamic nature of the laser tissue interaction and the need for temporal or spatial separation of pulses for optimum efficacy with regards to tissue removal. Overall, the application of picosecond laser pulses to ablate endoluminal bowel lesions demonstrates significantly improved precision and reduced thermal damage to the adjacent tissue in comparison to conventional procedures and hence will enable more precise surgical treatment of cancers.


Asunto(s)
Neoplasias Colorrectales/cirugía , Terapia por Láser , Animales , Modelos Animales de Enfermedad , Ratones , Porcinos
4.
J Infect ; 76(4): 383-392, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29248587

RESUMEN

BACKGROUND: Limited data exist describing supportive care management, laboratory abnormalities and outcomes in patients with Ebola virus disease (EVD) in West Africa. We report data which constitute the first description of the provision of enhanced EVD case management protocols in a West African setting. METHODS: Demographic, clinical and laboratory data were collected by retrospective review of clinical and laboratory records of patients with confirmed EVD admitted between 5 November 2014 and 30 June 2015. RESULTS: A total of 44 EVD patients were admitted (median age 37 years (range 17-63), 32/44 healthcare workers), and excluding those evacuated, the case fatality rate was 49% (95% CI 33%-65%). No pregnant women were admitted. At admission 9/44 had stage 1 disease (fever and constitutional symptoms only), 12/44 had stage 2 disease (presence of diarrhoea and/or vomiting) and 23/44 had stage 3 disease (presence of diarrhoea and/or vomiting with organ failure), with case fatality rates of 11% (95% CI 1%-58%), 27% (95% CI 6%-61%), and 70% (95% CI 47%-87%) respectively (p = 0.009). Haemorrhage occurred in 17/41 (41%) patients. The majority (21/40) of patients had hypokalaemia with hyperkalaemia occurring in 12/40 patients. Acute kidney injury (AKI) occurred in 20/40 patients, with 14/20 (70%, 95% CI 46%-88%) dying, compared to 5/20 (25%, 95% CI 9%-49%) dying who did not have AKI (p = 0.01). Ebola virus (EBOV) PCR cycle threshold value at baseline was mean 20.3 (SD 4.3) in fatal cases and 24.8 (SD 5.5) in survivors (p = 0.007). Mean national early warning score (NEWS) at admission was 5.5 (SD 4.4) in fatal cases and 3.0 (SD 1.9) in survivors (p = 0.02). Central venous catheters were placed in 37/41 patients and intravenous fluid administered to 40/41 patients (median duration of 5 days). Faecal management systems were inserted in 21/41 patients, urinary catheters placed in 27/41 and blood component therapy administered to 20/41 patients. CONCLUSIONS: EVD is commonly associated life-threatening electrolyte imbalance and organ dysfunction. We believe that the enhanced levels of protocolized care, scale and range of medical interventions we report, offer a blueprint for the future management of EVD in resource-limited settings.


Asunto(s)
Manejo de Caso , Fiebre Hemorrágica Ebola/terapia , Hospitalización/estadística & datos numéricos , Cuidados Paliativos/métodos , Adolescente , Adulto , África Occidental/epidemiología , Diarrea/epidemiología , Diarrea/virología , Ebolavirus/patogenicidad , Electrólitos , Femenino , Fiebre/epidemiología , Fiebre/virología , Recursos en Salud , Fiebre Hemorrágica Ebola/epidemiología , Registros de Hospitales , Humanos , Masculino , Persona de Mediana Edad , Instalaciones Militares , Estudios Retrospectivos , Sierra Leona/epidemiología , Reino Unido , Carga Viral , Adulto Joven
5.
J Evol Biol ; 29(11): 2266-2275, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27468122

RESUMEN

Sexually selected traits are often highly variable in size within populations due to their close link with the physical condition of individuals. Nutrition has a large impact on physical condition, and thus, any seasonal changes in nutritional quality are predicted to alter the average size of sexually selected traits as well as the degree of sexual dimorphism in populations. However, although traits affected by mate choice are well studied, we have a surprising lack of knowledge of how natural variation in nutrition affects the expression of sexually selected weapons and sexual dimorphism. Further, few studies explicitly test for differences in the heritability and mean-scaled evolvability of sexually selected traits across conditions. We studied Narnia femorata (Hemiptera: Coreidae), an insect where males use their hind legs as weapons and the femurs are enlarged, to understand the extent to which weapon expression, sexual dimorphism and evolvability change across the actual range of nutrition available in the wild. We found that insects raised on a poor diet (cactus without fruit) are nearly monomorphic, whereas those raised on a high-quality diet (cactus with ripe fruit) are distinctly sexually dimorphic via the expression of large hind leg weapons in males. Contrary to our expectations, we found little evidence of a potential for evolutionary change for any trait measured. Thus, although we show weapons are highly condition dependent, and changes in weapon expression and dimorphism could alter evolutionary dynamics, our populations are unlikely to experience further evolutionary changes under current conditions.


Asunto(s)
Evolución Biológica , Caracteres Sexuales , Animales , Hemípteros , Masculino , Fenotipo , Estaciones del Año
6.
Biol Lett ; 12(3): 20151064, 2016 03.
Artículo en Inglés | MEDLINE | ID: mdl-26979560

RESUMEN

Sexual conflict occurs when selection to maximize fitness in one sex does so at the expense of the other sex. In the burying beetle Nicrophorus vespilloides, repeated mating provides assurance of paternity at a direct cost to female reproductive productivity. To reduce this cost, females could choose males with low repeated mating rates or smaller, servile males. We tested this by offering females a dichotomous choice between males from lines selected for high or low mating rate. Each female was then allocated her preferred or non-preferred male to breed. Females showed no preference for males based on whether they came from lines selected for high or low mating rates. Pairs containing males from high mating rate lines copulated more often than those with low line males but there was a negative relationship between female size and number of times she mated with a non-preferred male. When females bred with their preferred male the number of offspring reared increased with female size but there was no such increase when breeding with non-preferred males. Females thus benefited from being choosy, but this was not directly attributable to avoidance of costly male repeated mating.


Asunto(s)
Escarabajos/fisiología , Preferencia en el Apareamiento Animal , Animales , Femenino , Masculino
7.
J Evol Biol ; 29(3): 541-50, 2016 03.
Artículo en Inglés | MEDLINE | ID: mdl-26749372

RESUMEN

Male parents face a choice: should they invest more in caring for offspring or in attempting to mate with other females? The most profitable course depends on the intensity of competition for mates, which is likely to vary with the population sex ratio. However, the balance of pay-offs may vary among individual males depending on their competitive prowess or attractiveness. We tested the prediction that sex ratio and size of the resource holding male provide cues regarding the level of mating competition prior to breeding and therefore influence the duration of a male's biparental caring in association with a female. Male burying beetles, Nicrophorus vespilloides were reared, post-eclosion, in groups that differed in sex ratio. Experimental males were subsequently translocated to the wild, provided with a breeding resource (carcass) and filmed. We found no evidence that sex ratio cues prior to breeding affected future parental care behaviour but males that experienced male-biased sex ratios took longer to attract wild mating partners. Smaller males attracted a higher proportion of females than did larger males, securing significantly more monogamous breeding associations as a result. Smaller males thus avoided competitive male-male encounters more often than larger males. This has potential benefits for their female partners who avoid both intrasexual competition and direct costs of higher mating frequency associated with competing males.


Asunto(s)
Escarabajos/fisiología , Razón de Masculinidad , Conducta Sexual Animal/fisiología , Animales , Tamaño Corporal , Escarabajos/anatomía & histología , Conducta Competitiva , Femenino , Masculino , Preferencia en el Apareamiento Animal
9.
J Hosp Infect ; 91(3): 275-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26319591

RESUMEN

In October 2014 the UK military deployed to Sierra Leone to provide care for healthcare workers affected by Ebola virus disease. A training package designed by the Army Medical Services Training Centre prepared the deploying personnel in the required infection prevention and control measures. The training used ultraviolet tracer to provide validation of the skills required when treating patients with Ebola and to confirm subsequent decontamination. This training construct provided useful feedback to clinicians on their infection control measures and would be useful in the context of any infection spread by droplets and fomites.


Asunto(s)
Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Control de Infecciones/métodos , Entrenamiento Simulado/métodos , Fiebre Hemorrágica Ebola/diagnóstico , Fiebre Hemorrágica Ebola/terapia , Humanos , Sierra Leona , Coloración y Etiquetado , Rayos Ultravioleta , Reino Unido
10.
J Evol Biol ; 28(7): 1394-402, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26033457

RESUMEN

Male parents spend less time caring than females in many species with biparental care. The traditional explanation for this pattern is that males have lower confidence of parentage, so they desert earlier in favour of pursuing other mating opportunities. However, one recent alternative hypothesis is that prolonged male parental care might also evolve if staying to care actively improves paternity. If this is the case, an increase in reproductive competition should be associated with increased paternal care. To test this prediction, we manipulated the level of reproductive competition experienced by burying beetles, Nicrophorus vespilloides (Herbst, 1783). We found that caregiving males stayed for longer and mated more frequently with their partner when reproductive competition was greater. Reproductive productivity did not increase when males extended care. Our findings provide support for the increased paternity hypothesis. Extended duration of parental care may be a male tactic both protecting investment (in the current brood) and maximizing paternity (in subsequent brood(s) via female stored sperm) even if this fails to maximize current reproductive productivity and creates conflict of interest with their mate via costs associated with increased mating frequency.


Asunto(s)
Escarabajos/fisiología , Conducta Paterna/fisiología , Conducta Sexual Animal , Animales , Conducta Competitiva/fisiología , Femenino , Masculino
11.
Nat Commun ; 6: 6818, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25879839

RESUMEN

Hepatocellular carcinoma (HCC) develops on the background of chronic hepatitis. Leukocytes found within the HCC microenvironment are implicated as regulators of tumour growth. We show that diethylnitrosamine (DEN)-induced murine HCC is attenuated by antibody-mediated depletion of hepatic neutrophils, the latter stimulating hepatocellular ROS and telomere DNA damage. We additionally report a previously unappreciated tumour suppressor function for hepatocellular nfkb1 operating via p50:p50 dimers and the co-repressor HDAC1. These anti-inflammatory proteins combine to transcriptionally repress hepatic expression of a S100A8/9, CXCL1 and CXCL2 neutrophil chemokine network. Loss of nfkb1 promotes ageing-associated chronic liver disease (CLD), characterized by steatosis, neutrophillia, fibrosis, hepatocyte telomere damage and HCC. Nfkb1(S340A/S340A)mice carrying a mutation designed to selectively disrupt p50:p50:HDAC1 complexes are more susceptible to HCC; by contrast, mice lacking S100A9 express reduced neutrophil chemokines and are protected from HCC. Inhibiting neutrophil accumulation in CLD or targeting their tumour-promoting activities may offer therapeutic opportunities in HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas Experimentales/genética , Subunidad p50 de NF-kappa B/genética , Neutrófilos/inmunología , Alquilantes/toxicidad , Animales , Calgranulina A/genética , Calgranulina B/genética , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/inmunología , Quimiocina CXCL1/genética , Quimiocina CXCL2/genética , Dietilnitrosamina/toxicidad , Hepatopatías/genética , Hepatopatías/inmunología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/inmunología , Ratones , Ratones Noqueados , Mutación
12.
J Evol Biol ; 28(2): 503-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25522811

RESUMEN

Parental care benefits offspring through maternal effects influencing their development, growth and survival. However, although parental care in general is likely the result of adaptive evolution, it does not follow that specific differences in the maternal effects that arise from care are also adaptive. Here, we used an interspecific cross-fostering design in the burying beetle species Nicrophorus orbicollis and N. vespilloides, both of which have elaborate parental care involving direct feeding of regurgitated food to offspring, to test whether maternal effects are optimized within a species and therefore adaptive. Using a full-factorial design, we first demonstrated that N. orbicollis care for offspring longer regardless of recipient species. We then examined offspring development and mass in offspring reared by hetero- or conspecific parents. As expected, there were species-specific direct effects independent of the maternal effects, as N. orbicollis larvae were larger and took longer to develop than N. vespilloides regardless of caregiver. We also found significant differences in maternal effects: N. vespilloides maternal care caused more rapid development of offspring of either species. Contrary to expectations if maternal effects were species-specific, there were no significant interactions between caretaker and recipient species for either development time or mass, suggesting that these maternal effects are general rather than optimized within species. We suggest that rather than coadaptation between parents and offspring performance, the species differences in maternal effects may be correlated with direct effects, and that their evolution is driven by selection on those direct effects.


Asunto(s)
Adaptación Fisiológica/genética , Escarabajos/fisiología , Conducta Materna/fisiología , Animales , Escarabajos/genética , Femenino , Masculino , Especificidad de la Especie
13.
Insect Mol Biol ; 23(3): 391-404, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24646461

RESUMEN

Flexible behaviour allows organisms to respond appropriately to changing environmental and social conditions. In the subsocial beetle Nicrophorus vespilloides, females tolerate conspecifics when mating, become aggressive when defending resources, and return to social tolerance when transitioning to parenting. Given the association between octopamine and aggression in insects, we hypothesized that genes in the octopaminergic system would be differentially expressed across different social and reproductive contexts. To test this in N. vespilloides, we first obtained the sequences of orthologues of the synthetic enzymes and receptors of the octopaminergic system. We next compared relative gene expression from virgin females, mated females, mated females alone on a resource required for reproduction and mated females on a resource with a male. Expression varied for five receptor genes. The expression of octopamine ß receptor 1 and octopamine ß receptor 2 was relatively higher in mated females than in other social conditions. Octopamine ß receptor 3 was influenced by the presence or absence of a resource and less by social environment. Octopamine α receptor and octopamine/tyramine receptor 1 gene expression was relatively lower in the mated females with a resource and a male. We suggest that in N. vespilloides the octopaminergic system is associated with the expression of resource defence, alternative mating tactics, social tolerance and indirect parental care.


Asunto(s)
Escarabajos/genética , Escarabajos/fisiología , Agresión , Animales , Secuencia de Bases , Femenino , Expresión Génica/fisiología , Masculino , Datos de Secuencia Molecular , Octopamina/biosíntesis , Octopamina/genética , Reproducción , Conducta Sexual Animal , Conducta Social
14.
Opt Express ; 21(18): 21119-30, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-24103987

RESUMEN

A technique for absolute phase measurement in fringe projection for shape measurement is presented. A standard fringe projection system is used, comprising a camera and a projector fixed relative to each other. The test object is moved to different orientations relative to the fringe projection system. Using the system calibration parameters, the technique identifies homologous surface areas imaged from different perspectives and resolves the 2 π phase ambiguity between them simultaneously. The technique is also used to identify regions of the phase maps corresponding to discrete surfaces on the object. The methods described are suitable for automatic shape measurement with a lightweight fringe projection probe mounted to a coordinate measuring machine.

15.
J Evol Biol ; 26(4): 832-42, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23516960

RESUMEN

Models for the evolution of cannibalism highlight the importance of asymmetries between individuals in initiating cannibalistic attacks. Studies may include measures of body size but typically group individuals into size/age classes or compare populations. Such broad comparisons may obscure the details of interactions that ultimately determine how socially contingent characteristics evolve. We propose that understanding cannibalism is facilitated by using an interacting phenotypes perspective that includes the influences of the phenotype of a social partner on the behaviour of a focal individual and focuses on variation in individual pairwise interactions. We investigated how relative body size, a composite trait between a focal individual and its social partner, and the sex of the partners influenced precannibalistic aggression in the endangered Socorro isopod, Thermosphaeroma thermophilum. We also investigated whether differences in mating interest among males and females influenced cannibalism in mixed sex pairs. We studied these questions in three populations that differ markedly in range of body size and opportunities for interactions among individuals. We found that relative body size influences the probability of and latency to attack. We observed differences in the likelihood of and latency to attack based on both an individual's sex and the sex of its partner but found no evidence of sexual conflict. The instigation of precannibalistic aggression in these isopods is therefore a property of both an individual and its social partner. Our results suggest that interacting phenotype models would be improved by incorporating a new conditional ψ, which describes the strength of a social partner's influence on focal behaviour.


Asunto(s)
Canibalismo , Especies en Peligro de Extinción , Isópodos/fisiología , Conducta Social , Agresión/fisiología , Animales , Tamaño Corporal , Femenino , Masculino , Fenotipo , Factores Sexuales , Especificidad de la Especie
17.
J Evol Biol ; 25(11): 2232-41, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22984915

RESUMEN

Our expectations for the evolution of chemical signals in response to sexual selection are uncertain. How are chemical signals elaborated? Does sexual selection result in complexity of the composition or in altered quantities of expression? We addressed this in Drosophila pseudoobscura by examining male and female cuticular hydrocarbons (CHs) after 82 generations of elevated (E) sexual selection or relaxed sexual selection through monogamy (M). The CH profile consisted of 18 different components. We extracted three eigenvectors using principal component analysis that explained 72% of the variation. principal component (PC)1 described the amount of CHs produced, PC2 the trade-off between short- and long-chain CHs and PC3 the trade-off between apparently arbitrary CHs. In both sexes, the amount of CHs produced was greater in flies from the E treatment. PC3 was also higher, indicating that sexual selection also influenced the evolution of CH composition. The sexes differed in all three PCs, indicating substantial sexual dimorphism in this species, although the magnitude of this dimorphism was not increased as a result of our experimental evolution. Collectively, our work provides direct evidence that sexual selection plays an important role in the evolution of CHs in D. pseudoobscura and that both increased quantity and overall composition are targeted.


Asunto(s)
Evolución Biológica , Drosophila/química , Hidrocarburos Aromáticos/química , Conducta Sexual Animal/fisiología , Animales , Tamaño Corporal , Drosophila/anatomía & histología , Drosophila/fisiología , Femenino , Masculino , Análisis de Componente Principal , Selección Genética , Caracteres Sexuales , Especificidad de la Especie , Alas de Animales/anatomía & histología
18.
J Evol Biol ; 25(5): 803-12, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22404372

RESUMEN

Sexual selection arises from social interactions, and if social environments vary so too should sexual selection. For example, male-male competition often occurs either in the presence or in the absence of females, and such changes in the social environment could affect the form and strength of sexual selection. Here we examine how the presence of a female influences selection arising from male-male competition in a leaf-footed cactus bug, Narnia femorata, which has a resource defence mating system. Males compete for territories on cacti because females lay eggs on the cactus plants. Females are not always present when this competition first occurs; however, the presence or absence of the female matters. We found that both the form and strength of selection on male traits, those traits that influenced success in intrasexual competition, depended on the social context. When a female was not present, male size and the area of the sexually dimorphic hind legs was only marginally important to winning a contest. However, males with larger overall size and leg area were more likely to win in the presence of a female. There was also positive quadratic selection on these traits when a female was present with both the largest and the smallest males winning. The implication is unexpected alternative strategies when females are present. Our results support the notion that sexual selection should be studied under all relevant social contexts.


Asunto(s)
Conducta Competitiva/fisiología , Heterópteros/fisiología , Preferencia en el Apareamiento Animal/fisiología , Medio Social , Estructuras Animales/fisiología , Animales , Tamaño Corporal , Femenino , Modelos Logísticos , Masculino , Análisis de Componente Principal , Factores Sexuales , Territorialidad
19.
J Evol Biol ; 25(5): 873-80, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22356585

RESUMEN

A tenet of life history evolution is that allocation of limited resources results in trade-offs, such as that between reproduction and lifespan. Reproduction and lifespan are also influenced proximately by differences in the availability of specific nutrients. What is unknown is how the evolution of the ability to use a nutritionally novel diet is reflected in this fundamental trade-off. Does the evolution of the ability to use a nutritionally novel food maintain the trade-off in reproduction and longevity, or do the proximate effects of nutrition alter the adapted trade-off? We tested this by measuring trade-offs in male milkweed bugs, Oncopeltus fasciatus, fed either an adapted diet of sunflower or the ancestral diet of milkweed. Sunflower-fed males lived longer but invested less in reproduction, both in mating and fertility. Milkweed-fed males invested in both mating and fertility at the expense of survival. The evolution of an expanded diet was not constrained by the existing trade-off, but instead was accompanied by a different trade-off between reproduction and longevity. We suggest that this occurs because diets differ in promoting germ line development or longevity.


Asunto(s)
Adaptación Fisiológica , Dieta , Heterópteros/fisiología , Longevidad , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Asclepias , Evolución Biológica , Conducta Alimentaria , Femenino , Fertilidad/fisiología , Aptitud Genética , Helianthus , Masculino , Semillas , Conducta Sexual Animal , Maduración Sexual , Factores de Tiempo
20.
Opt Express ; 19(19): 18458-69, 2011 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-21935214

RESUMEN

A technique to produce phase steps in a fringe projection system for shape measurement is presented. Phase steps are produced by introducing relative rotation between the object and the fringe projection probe (comprising a projector and camera) about the camera's perspective center. Relative motion of the object in the camera image can be compensated, because it is independent of the distance of the object from the camera, whilst the phase of the projected fringes is stepped due to the motion of the projector with respect to the object. The technique was validated with a static fringe projection system by moving an object on a coordinate measuring machine (CMM). The alternative approach, of rotating a lightweight and robust CMM-mounted fringe projection probe, is discussed. An experimental accuracy of approximately 1.5% of the projected fringe pitch was achieved, limited by the standard phase-stepping algorithms used rather than by the accuracy of the phase steps produced by the new technique.

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