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2.
Prev Vet Med ; 181: 105063, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32593083

RESUMEN

Ectoparasitic salmon louse (Lepeophtheirus salmonis) infestations are costly for Atlantic salmon (Salmo salar) farmers in Norway. As a result, there is a strong desire for solutions to prevent and control infestations, and new technologies are typically developed and commercialised rapidly, without rigorous validation. Here, we tested the efficacy of a new commercially available control measure-delousing by underwater lasers-using a replicated design at full commercial scale. Laser delousing was used in combination with a preventive method (snorkel cages), with laser nodes deployed in 3 of the 6 sea cages at the site. The trial ran for 54 days, after which time there was no difference in infestation density of mobile salmon louse stages (pre-adult, adult male or adult female) in cages with or without laser nodes installed. By the end of the trial, adult female lice numbers in all cages were close to the legislated trigger for mandatory delousing (0.5 adult female lice per fish). The laser nodes delivered a large number of pulses relative to the number of lice in the cages, indicating that a lack of lethality rather than a lack of target detection was the limiting factor. If all pulses had been effective, they should have removed between 4-38 % of mobile lice each day. There was no effect on salmon welfare indicators such as skin condition or eye status. Our results highlight the importance of rigorous validation of new technologies across a range of conditions before widespread implementation by industry.


Asunto(s)
Acuicultura/métodos , Copépodos/fisiología , Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Peces/prevención & control , Rayos Láser/estadística & datos numéricos , Salmo salar , Animales , Infestaciones Ectoparasitarias/parasitología , Infestaciones Ectoparasitarias/prevención & control , Enfermedades de los Peces/parasitología , Noruega
3.
J Vis Exp ; (136)2018 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-30010669

RESUMEN

The goal of this protocol is to present how to perform spin- and angle-resolved photoemission spectroscopy combined with polarization-variable 7-eV laser (laser-SARPES), and demonstrate a power of this technique for studying solid state physics. Laser-SARPES achieves two great capabilities. Firstly, by examining orbital selection rule of linearly polarized lasers, orbital selective excitation can be carried out in SAPRES experiment. Secondly, the technique can show full information of a variation of the spin quantum axis as a function of the light polarization. To demonstrate the power of the collaboration of these capabilities in laser-SARPES, we apply this technique for the investigations of spin-orbit coupled surface states of Bi2Se3. This technique affords to decompose spin and orbital components from the spin-orbit coupled wavefunctions. Moreover, as a representative advantage of using the direct spin detection collaborated with the polarization-variable laser, the technique unambiguously visualizes the light polarization dependence of the spin quantum axis in three-dimension. Laser-SARPES dramatically increases a capability of photoemission technique.


Asunto(s)
Rayos Láser/estadística & datos numéricos , Espectroscopía de Fotoelectrones/métodos
4.
J Vis Exp ; (135)2018 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-29912185

RESUMEN

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (Cu variant) entropy-stabilized oxides. Phase pure and chemically homogeneous (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (x = 0.20, 0.27, 0.33) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (x = 0.11, 0.27) ceramic pellets are synthesized and used in the deposition of ultra-high quality, phase pure, single crystalline thin films of the target stoichiometry. A detailed methodology for the deposition of smooth, chemically homogeneous, entropy-stabilized oxide thin films by pulsed laser deposition on (001)-oriented MgO substrates is described. The phase and crystallinity of bulk and thin film materials are confirmed using X-ray diffraction. Composition and chemical homogeneity are confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The surface topography of thin films is measured with scanning probe microscopy. The synthesis of high quality, single crystalline, entropy-stabilized oxide thin films enables the study of interface, size, strain, and disorder effects on the properties in this new class of highly disordered oxide materials.


Asunto(s)
Rayos Láser/estadística & datos numéricos , Óxidos/química , Entropía
5.
J Vis Exp ; (135)2018 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-29863678

RESUMEN

As the field of tissue engineering has continued to mature, there has been increased interest in a wide range of tissue parameters, including tissue shape. Manipulating tissue shape on the micrometer to centimeter scale can direct cell alignment, alter effective mechanical properties, and address limitations related to nutrient diffusion. In addition, the vessel in which a tissue is prepared can impart mechanical constraints on the tissue, resulting in stress fields that can further influence both the cell and matrix structure. Shaped tissues with highly reproducible dimensions also have utility for in vitro assays in which sample dimensions are critical, such as whole tissue mechanical analysis. This manuscript describes an alternative fabrication method utilizing negative master molds prepared from laser etched acrylic: these molds perform well with polydimethylsiloxane (PDMS), permit designs with dimensions on the centimeter scale and feature sizes smaller than 25 µm, and can be rapidly designed and fabricated at a low cost and with minimal expertise. The minimal time and cost requirements allow for laser etched molds to be rapidly iterated upon until an optimal design is determined, and to be easily adapted to suit any assay of interest, including those beyond the field of tissue engineering.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Hidrogeles/metabolismo , Rayos Láser/estadística & datos numéricos , Ingeniería de Tejidos/métodos
6.
J Trop Pediatr ; 64(2): 146-150, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28673047

RESUMEN

Anthropometric measurements, including height and length, are routinely needed for health research worldwide. Measurement boards are the current gold standard for obtaining the height and length of children. In community-based research, however, the size and weight of the measurement boards make them difficult and cumbersome to carry in the field. In addition, children and infants may express an unwillingness to be placed onto the measurement board. Electronic measuring tools commonly used in industry and contracting work are precise and portable. This study piloted a protocol to use an adapted laser measurement tool, the anthropometric measurement assist (AMA), to obtain height and recumbent length in children in Western Kenya. Intra- and inter-observer variability were determined and compared with measurement board measurements. Results of this initial pilot indicated that the AMA may be a viable alternative to measurement boards. The AMA can measure height/length accurately and reliably, is portable and is equivalent in price to measuring boards, making it a viable option for fieldwork in low-resourced countries.


Asunto(s)
Antropometría/instrumentación , Rayos Láser/estadística & datos numéricos , Salud Pública/métodos , Niño , Preescolar , Femenino , Humanos , Lactante , Kenia , Masculino , Variaciones Dependientes del Observador , Proyectos Piloto , Reproducibilidad de los Resultados
7.
Curr Protoc Immunol ; 119: 5.8.1-5.8.38, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29091263

RESUMEN

The immune system consists of a complex network of cells, all expressing a wide range of surface and/or intracellular proteins. Using flow cytometry, these cells can be analyzed by labeling with fluorophore-conjugated antibodies. The recent expansion of fluorescence flow cytometry technology, in conjunction with the ever-expanding understanding of the complexity of the immune system, has led to the generation of larger high-dimensional fluorescence flow cytometry panels. However, as panel size and complexity increases, so too does the difficulty involved in constructing high-quality panels, in addition to the challenges of analyzing such high-dimensional datasets. As such, this unit seeks to review the key principles involved in building high-dimensional panels, as well as to guide users through the process of building and analyzing quality panels. Here, cytometer configuration, fluorophore brightness, spreading error, antigen density, choosing the best conjugates, titration, optimization, and data analysis will all be addressed. © 2017 by John Wiley & Sons, Inc.


Asunto(s)
Anticuerpos/metabolismo , Citometría de Flujo/métodos , Colorantes Fluorescentes , Rayos Láser/estadística & datos numéricos , Análisis de la Célula Individual , Animales , Antígenos/inmunología , Antígenos/metabolismo , Conjuntos de Datos como Asunto , Citometría de Flujo/instrumentación , Fluorescencia , Colorantes Fluorescentes/química , Humanos
8.
J Vis Exp ; (124)2017 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-28715366

RESUMEN

An original method to heat cultured cells using a 1.94 µm continuous-wave thulium laser for biological assessment is introduced here. Thulium laser radiation is strongly absorbed by water, and the cells at the bottom of the culture dish are heated through thermal diffusion. A laser fiber with a diameter of 365 µm is set about 12 cm above the culture dish, without any optics, such that the laser beam diameter is almost equivalent to the inner diameter of the culture dish (30 mm). By keeping a consistent amount of culture medium in each experiment, it is possible to irradiate the cells with a highly reproducible temperature increase. To calibrate the temperature increase and its distribution in one cell culture dish for each power setting, the temperature was measured during 10 s of irradiation at different positions and at the cellular level. The temperature distribution was represented using a mathematical graphics software program, and its pattern across the culture dish was in Gaussian form. After laser irradiation, different biological experiments could be performed to assess temperature-dependent cell responses. In this manuscript, viability staining (i.e., distinguishing live, apoptotic, and dead cells) is introduced to help determine the threshold temperatures for cell apoptosis and death after different points in time. The advantages of this method are the preciseness of the temperature and the time of heating, as well as its high efficiency in heating cells in a whole cell culture dish. Furthermore, it allows for study with a wide variety of temperatures and time durations, which can be well-controlled by a computerized operating system.


Asunto(s)
Células Cultivadas/metabolismo , Terapia por Láser/métodos , Rayos Láser/estadística & datos numéricos , Tulio/química , Células Cultivadas/citología , Calefacción
9.
Methods Mol Biol ; 1607: 273-294, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28573577

RESUMEN

Time-resolved macromolecular crystallography unifies protein structure determination with chemical kinetics. With the advent of fourth generation X-ray sources the time-resolution can be on the order of 10-40 fs, which opens the ultrafast time scale to structure determination. Fundamental motions and transitions associated with chemical reactions in proteins can now be observed. Moreover, new experimental approaches at synchrotrons allow for the straightforward investigation of all kind of reactions in biological macromolecules. Here, recent developments in the field are reviewed.


Asunto(s)
Cristalografía por Rayos X/métodos , Proteínas/ultraestructura , Cristalografía por Rayos X/instrumentación , Cinética , Rayos Láser/estadística & datos numéricos , Conformación Proteica , Proteínas/química , Sincrotrones/instrumentación , Termodinámica , Factores de Tiempo , Difracción de Rayos X
10.
Artículo en Inglés | MEDLINE | ID: mdl-28374983

RESUMEN

We show the use of a new endoscopic drill for the management of web-like tracheal stenosis. Our device creates radial holes within stenosis that facilitate the use of scissors for cutting the scar tissue and the subsequent mechanical dilatation.


Asunto(s)
Dilatación/métodos , Endoscopía/instrumentación , Estenosis Traqueal/cirugía , Broncoscopía/instrumentación , Broncoscopía/métodos , Endoscopía/métodos , Humanos , Intubación Intratraqueal/efectos adversos , Rayos Láser/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estenosis Traqueal/etiología , Traqueostomía/efectos adversos , Resultado del Tratamiento
11.
Rev. cuba. oftalmol ; 30(1): 0-0, ene.-mar. 2017.
Artículo en Español | LILACS | ID: biblio-901349

RESUMEN

La aplicación del femtoláser en la cirugía de catarata podría ser una de las grandes revoluciones contemporáneas ocurridas en el campo del tratamiento de la catarata. Si el uso de esta tecnología provocara una eficacia y seguridad muy superiores sobre la facoemulsificación convencional, justificaría el alto costo que genera para la cirugía de catarata en la actualidad. En revisiones de estudios comparativos no se han encontrado diferencias significativas entre los resultados visuales de ambos procedimientos al final del período de seguimiento posoperatorio. Una mejor circularidad de la capsulorrexis, unido a disminución en la emisión de energía ultrasónica y del tiempo efectivo de faco, son atribuidos como las grandes ventajas del uso del femtoláser en la facoemulsificación. Sin embargo, en cuanto a la pérdida de células endoteliales, el edema corneal posoperatorio y el edema macular posquirúrgico no se han registrado grandes diferencias entre ambas técnicas quirúrgicas, mientras que el costo de la cirugía se incrementa considerablemente con la utilización del femtoláser. Por tanto, se necesitan estudios de gran tamaño de muestra bien diseñados que proporcionen evidencias más fiables respecto al uso del femtoláser en la cirugía de catarata actual(AU)


The application of femtoláser in cataract surgery could be one of the great contemporary revolutions occurred in the field of treatment of cataract. If the use of this technology would cause a very superior efficacy and safety over conventional phacoemulsification, it justifies the high cost it generates for cataract surgery today. In reviews of comparative studies we have not found significant differences between the visual results of both procedures at the end of the period of postoperative follow-up. Better circularity of the capsulorhexis, coupled with decrease in the emission of ultrasonic energy and effective phacoemulsification time, are attributed as the major advantages of using femtoláser in phacoemulsification. However in terms of endothelial cell loss, postoperative corneal edema and macular edema after surgery they have not been recorded big differences between the two surgical techniques, while the cost of surgery is considerably increased with the use of femtoláser. Therefore studies of large sample size, well-designed to provide more reliable evidence regarding the use of femtoláser in current cataract surgery are needed(AU)


Asunto(s)
Humanos , Extracción de Catarata/métodos , Facoemulsificación/métodos , Rayos Láser/estadística & datos numéricos , Desarrollo Tecnológico/análisis
12.
Artículo en Inglés | MEDLINE | ID: mdl-28106972

RESUMEN

We propose the use of a new endoscopic drill for management of web-like tracheal stenosis. Our device allows creating radial holes within stenosis that facilitates the use of the scissors for cutting the  scar and the subsequent mechanical dilatation.


Asunto(s)
Broncoscopía/instrumentación , Dilatación/métodos , Endoscopía/instrumentación , Estenosis Traqueal/cirugía , Broncoscopía/métodos , Endoscopía/métodos , Humanos , Intubación Intratraqueal , Rayos Láser/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estenosis Traqueal/etiología
13.
Chem Commun (Camb) ; 52(66): 10147-50, 2016 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-27456171

RESUMEN

Smooth and solid WS2 submicrospheres were prepared by a laser irradiation induced fragmentation and morphological reshaping process using bulk-slice WS2 particles as targets in solution. Such submicrospheres as additives in paraffin liquid show remarkably enhanced friction reduction and anti-wear properties in comparison with raw WS2 slices.


Asunto(s)
Productos Biológicos/síntesis química , Rayos Láser/estadística & datos numéricos , Microesferas , Compuestos de Tungsteno/síntesis química , Ensayo de Materiales/métodos , Propiedades de Superficie
14.
ImplantNewsPerio ; 1(4): 758-765, mai.-jun. 2016. ilus
Artículo en Portugués | LILACS, BBO | ID: biblio-847039

RESUMEN

Existem condições clínicas em Periodontia na qual o freio labial está posicionado de forma penetrante nas papilas gengivais, ficando muito próximo à margem gengival, podendo predispor ao desenvolvimento de recessões gengivais. Também pode ocorrer dificuldade de higienização, infl amação persistente, restrição no movimento labial, interferência fonética e agravos estéticos, além de dificultar o fechamento de diastemas. Muitas vezes, é indicada a remoção cirúrgica de freios labiais utilizando lâminas de bisturi e, mais recentemente, o laser de alta intensidade. O laser, ao ser absorvido pelos tecidos, gera a vaporização e sublimação, resultando em corte e exérese, além de atuar como auxiliar na cicatrização, provavelmente através da bioestimulação. Seu meio ativo promove a vaporização completa e a coagulação nos tecidos, sem gerar propagação do aquecimento. Há maior controle da hemorragia transoperatória, resultando em um procedimento cirúrgico limpo, frequentemente dispensando suturas, facilitando a visibilidade, execução e remoção do freio labial. O objetivo deste trabalho foi demonstrar as vantagens do laser cirúrgico de alta intensidade (Nd:YAG; 808 nm; 1,2 W; 20 pps; 126 J) a partir de um relato de caso clínico de frenectomia realizada em uma paciente do sexo feminino, com 34 anos de idade, que apresenta freio labial persistente associado a diastema interincisal superior. O procedimento cirúrgico com laser de alta intensidade em tecidos moles apresentou algumas vantagens, como a redução do tempo cirúrgico, de morbidade e sintomatologia pós-operatórias.


There are clinical conditions in periodontics where the labia frenulum is deeply positioned into the gingival papillae getting very close to the gingival margins, predisposing the development of recessions, causing difficulties for cleaning, with persistent infl ammation, lip movement restrictions, phonetic interference, esthetic alteration, besides preventing diastema closure. Oftentimes, removal with a surgical blade or high-intensity lasers is recommended. The laser is absorbed by the tissues generating vaporization and sublimation which results in cutting and excision, and increased improved healing possibly due to its bio-stimulatory effect. Its active medium promotes complete tissue vaporization and coagulation, without heat propagation, control of the intraoperative bleeding and a clean surgery that often does not require sutures. This facilitates visibility, execution and removal of the labial frenulum. The aim of this paper was to demonstrate the surgical benefi ts of the high-intensity laser (Nd:YAG; 808 nm; 1.2 W; 20 pps; 126 J) in a case report of frenectomy for a 34 years-old female patient presenting persistent inter-incisal diastema associated with an atypical labial frenulum. The soft tissue laser therapy has the advantage of reduced clinical time and still not promoting edema, with minimal postoperative pain and side effects.


Asunto(s)
Humanos , Femenino , Adulto , Frenillo Labial/cirugía , Terapia por Láser , Rayos Láser/estadística & datos numéricos , Periodoncia
15.
ImplantNewsPerio ; 1(1): 58-66, jan.-fev. 2016. ilus
Artículo en Portugués | LILACS, BBO | ID: biblio-846988

RESUMEN

Objetivo: fazer uma revisão da literatura sobre o laser de baixa intensidade (LLLT) e seus efeitos na osseointegração dos implantes de titânio. Material e métodos: uma busca eletrônica foi realizada nos bancos de dados PubMed/Medline e Cochrane Library, entre 1995 e 2015, limitando-se aos artigos em inglês e usando as seguintes palavras-chave: "LLLT", "dental implant" e "osseointegration", combinadas por operadores booleanos. Resultados: das 96 referências analisadas inicialmente, apenas 17 artigos foram incluídos (15 estudos em animais, dois estudos em humanos). Quinze artigos mostraram efeitos positivos da LLLT, enquanto dois foram neutros. Houve grande variabilidade no uso da LLLT, sobretudo no que se refere à dose utilizada, ao número de sessões, à energia de irradiação, e ao comprimento de onda. Conclusão: mais pesquisas sobre este tema são necessárias, utilizando doses padronizadas, assim como comprimento de onda e protocolos de aplicação pré-definidos.


Objective: to perform a systematic review on low-level laser therapy (LLLT) and its effects on the osseointegration of titanium implants. Material and methods: an electronic search was on the PubMed/Medline database and Cochrane Library between 1995 e 2015, restricted to the English literature and using the keywords: "LLLT", "dental implant", and "osseointegration" combined by Boolean operators. Results: from the 96 initially retrieved references, only 17 articles were included (15 animal studies, 2 human studies). Fifteen articles showed positive effects, while only two demonstrated neutral effects of LLLT. A great variability was found on LLLT regarding doses, number of sessions, energy, and wavelengths used. Conclusion: further research on this topic need to be made using standard doses, wavelengths, and pre-defi ned application protocols.


Asunto(s)
Humanos , Terapia por Láser , Rayos Láser/estadística & datos numéricos , Terapia por Luz de Baja Intensidad , Oseointegración/efectos de la radiación
16.
Food Chem ; 194: 366-72, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26471567

RESUMEN

The effect of pulsed light (from 1.75 to 26.25Jcm(-2)) on selected properties of wheat gluten powder and aqueous suspension (absorbance, particle size and microstructure, free sulfhydryl content, protein fractions, protein electrophoretic mobility and immunoreactivity) was investigated. Gluten photoreactivity was strongly affected by hydration. While minor photo-induced structure modifications were observed in gluten powder, pulsed light induced the development of browning and promoted partial depolymerisation of hydrated gluten proteins by disulphide exchange. These changes were associated with a significant decrease in immunoreactivity, suggesting that pulsed light could be exploited to efficiently modify structure and thus functionality of gluten.


Asunto(s)
Electroforesis en Gel de Poliacrilamida/métodos , Glútenes/química , Rayos Láser/estadística & datos numéricos , Triticum/química
17.
Sci Rep ; 5: 14742, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26439499

RESUMEN

Cataract surgery is the most common surgical procedure and femtosecond laser assisted cataract surgery (FLACS) has gained increased popularity. FLACS requires the application of a suction device to stabilize the laser head and focus the laser beam accurately. This may cause a significant escalation in intra-ocular pressure (IOP), which poses potential risks for patients undergoing cataract surgery. In this study we aimed to assess the effect of the Ziemer LDV Z8 femtosecond cataract machine on IOP. We demonstrated through a porcine model that IOP was significantly higher with a flat interface but could be abrogated by reducing surgical compression and vacuum. Pressure was lower with a liquid interface, and further altering angulation of the laser arm could reduce the IOP to 36 mmHg. A pilot series in patients showed comparable pressure rises with the porcine model (30 mmHg). These strategies may improve the safety profile in patients vulnerable to high pressure when employing FLACS with the Ziemer LDV Z8.


Asunto(s)
Catarata/terapia , Presión Intraocular/fisiología , Rayos Láser/estadística & datos numéricos , Tonometría Ocular/instrumentación , Anciano , Animales , Humanos , Porcinos
18.
Acta Crystallogr F Struct Biol Commun ; 71(Pt 7): 856-60, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26144230

RESUMEN

Rhodopsin is a membrane protein from the G protein-coupled receptor family. Together with its ligand retinal, it forms the visual pigment responsible for night vision. In order to perform ultrafast dynamics studies, a time-resolved serial femtosecond crystallography method is required owing to the nonreversible activation of rhodopsin. In such an approach, microcrystals in suspension are delivered into the X-ray pulses of an X-ray free-electron laser (XFEL) after a precise photoactivation delay. Here, a millilitre batch production of high-density microcrystals was developed by four methodical conversion steps starting from known vapour-diffusion crystallization protocols: (i) screening the low-salt crystallization conditions preferred for serial crystallography by vapour diffusion, (ii) optimization of batch crystallization, (iii) testing the crystal size and quality using second-harmonic generation (SHG) imaging and X-ray powder diffraction and (iv) production of millilitres of rhodopsin crystal suspension in batches for serial crystallography tests; these crystals diffracted at an XFEL at the Linac Coherent Light Source using a liquid-jet setup.


Asunto(s)
Rayos Láser/estadística & datos numéricos , Rodopsina/química , Difracción de Rayos X/métodos , Animales , Bovinos , Cristalización
19.
PLoS One ; 10(6): e0129175, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26035303

RESUMEN

Marking organisms with fluorescent dyes and powders is a common technique used in ecological field studies that monitor movement of organisms to examine life history traits, behaviors, and population dynamics. External fluorescent marking is relatively inexpensive and can be readily employed to quickly mark large numbers of individuals; however, the ability to detect marked organisms in the field at night has been hampered by the limited detection distances provided by portable fluorescent ultraviolet lamps. In recent years, significant advances in LED lamp and laser technology have led to development of powerful, low-cost ultraviolet light sources. In this study, we evaluate the potential of these new technologies to improve detection of fluorescent-marked organisms in the field and to create new possibilities for tracking marked organisms in visually challenging environments such as tree canopies and aquatic habitats. Using handheld lasers, we document a method that provides a fivefold increase in detection distance over previously available technologies. This method allows easy scouting of tree canopies (from the ground), as well as shallow aquatic systems. This novel detection method for fluorescent-marked organisms thus promises to significantly enhance the use of fluorescent marking as a non-destructive technique for tracking organisms in natural environments, facilitating field studies that aim to document otherwise inaccessible aspects of the movement, behavior, and population dynamics of study organisms, including species with significant economic impacts or relevance for ecology and human health.


Asunto(s)
Sistemas de Identificación Animal/métodos , Colorantes Fluorescentes/química , Heterópteros/química , Rayos Láser/estadística & datos numéricos , Animales , Humanos , Dinámica Poblacional
20.
Plant J ; 83(3): 555-65, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26095749

RESUMEN

Manganese (Mn) constitutes an essential co-factor in the oxygen-evolving complex of photosystem II (PSII). Consequently, Mn deficiency reduces photosynthetic efficiency and leads to changes in PSII composition. In order to study these changes, multiplexed protein assays are advantageous. Here, we developed a multiplexed antibody-based assay and analysed selected PSII subunits in barley (Hordeum vulgare L.). A selection of antibodies were labelled with specific lanthanides and immunoreacted with thylakoids exposed to Mn deficiency after western blotting. Subsequently, western blot membranes were analysed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), which allowed selective and relative quantitative analysis via the different lanthanides. The method was evaluated against established liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) methods, based on data-dependent acquisition (DDA) and selected reaction monitoring (SRM). Manganese deficiency resulted in a general decrease in PSII protein abundances, an effect that was shown to be reversible upon Mn re-supplementation. Specifically, the extrinsic proteins PsbP and PsbQ showed Mn-dependent changes in abundances. Similar trends in the response to Mn deficiency at the protein level were observed when comparing DDA, SRM and LA-ICP-MS results. A biologically important exception to this trend was the loss of PsbO in the SRM analysis, which highlights the necessity of validating protein changes by more than one technique. The developed method enables a higher number of proteins to be multiplexed in comparison to existing immunoassays. Furthermore, multiplexed protein analysis by LA-ICP-MS provides an analytical platform with high throughput appropriate for screening large collections of plants.


Asunto(s)
Hordeum/metabolismo , Rayos Láser/estadística & datos numéricos , Manganeso/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Immunoblotting , Espectrometría de Masa por Ionización de Electrospray
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