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1.
J Therm Biol ; 66: 87-92, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28477914

RESUMO

Hand skin temperature measurements have previously been performed on either dorsal or palmar sides and it is possible to find arguments for the advantage of both locations. Therefore, the aim of this study was to use dynamic infrared (IR) imaging to examine the relationship between dorsal and palmar hand skin temperature. The palmar and dorsal hand skin temperature before and after a cold stress test was measured with IR thermography in 112 healthy participants. Calculation of surface average temperature was made from nine regions of interest on each hand's dorsal and palmar side. Temperature values were recorded at baseline, directly after immersion of hands in vinyl gloves for one minute in water at 20 ±0.5 °C (gloves removed), and after eight minutes rewarming. Results showed that: a) the skin temperatures on the dorsal and palmar sides of the hand are strongly correlated; b) the correlation is stronger on the fingers than on the carpometacarpal (CMC) area; c) the palmar side of the CMC area is warmer than the dorsal side, but this is reversed in the fingers so that the nail bed is warmer than the finger pad; and d) the temperature difference ∆T between the dorsal and palmar sides of the fingers is independent of the skin temperature, though ∆T on the CMC area of the hand is temperature dependent. Such differences can be important in detailed investigations of thermal phenomena in the hand. In conclusion, results showed a strong correlation between the dorsal and palmar temperatures. If both sides cannot be measured, the purpose of the investigation should determine which side of the hand should be measured.


Assuntos
Temperatura Baixa , Temperatura Cutânea , Dedos/fisiologia , Mãos/fisiologia , Humanos
2.
Theriogenology ; 93: 46-54, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28257866

RESUMO

The expression and localization of VEGFA and its main receptors Flt-1 and KDR is characterized in the oviduct throughout the porcine estrous cycle. Oviducts were sampled from sows at early follicular, late follicular, early luteal and late luteal stages of the estrous cycle and a segment from the mid portion of the ampulla and isthmus studied by real time RT-PCR and quantitative immunohistochemistry. The expression of the three components of the VEGF system was continuous, although differences were observed depending on the oviduct portion, the stage of the estrous cycle and the histological layer. VEGFA and KDR mRNA expressions were higher in ampulla, while Flt-1 mRNA was higher in isthmus. VEGFA protein was also higher in ampulla but Flt-1 and KDR did not show regional differences between ampulla and isthmus. While the mRNA expression of VEGFA, Flt-1 and KDR increased progressively during the luteal period, the amount of VEGFA and Flt-1 protein decreased in the same period (in isthmus only). Contrastinly, KDR protein peaked in ampulla and isthmus just before ovulation. The VEGF system was majorly located in both the secretory and ciliated cells of the oviduct epithelium, but also in the endothelium and fibroblasts of the lamina propia and the muscle fibres and vessels of the tunica muscularis. Our results are consistent with a participation of VEFG in the regulation of the dynamics of oviductal fluid secretion and the oviduct contractibility.


Assuntos
Ciclo Estral/metabolismo , Tubas Uterinas/metabolismo , Sus scrofa , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Tubas Uterinas/química , Feminino , Imuno-Histoquímica , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/análise , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
3.
Heredity (Edinb) ; 117(4): 279-89, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27328654

RESUMO

The Scandinavian wolf population descends from only five individuals, is isolated, highly inbred and exhibits inbreeding depression. To meet international conservation goals, suggestions include managing subdivided wolf populations over Fennoscandia as a metapopulation; a genetically effective population size of Ne⩾500, in line with the widely accepted long-term genetic viability target, might be attainable with gene flow among subpopulations of Scandinavia, Finland and Russian parts of Fennoscandia. Analytical means for modeling Ne of subdivided populations under such non-idealized situations have been missing, but we recently developed new mathematical methods for exploring inbreeding dynamics and effective population size of complex metapopulations. We apply this theory to the Fennoscandian wolves using empirical estimates of demographic parameters. We suggest that the long-term conservation genetic target for metapopulations should imply that inbreeding rates in the total system and in the separate subpopulations should not exceed Δf=0.001. This implies a meta-Ne of NeMeta⩾500 and a realized effective size of each subpopulation of NeRx⩾500. With current local effective population sizes and one migrant per generation, as recommended by management guidelines, the meta-Ne that can be reached is ~250. Unidirectional gene flow from Finland to Scandinavia reduces meta-Ne to ~130. Our results indicate that both local subpopulation effective sizes and migration among subpopulations must increase substantially from current levels to meet the conservation target. Alternatively, immigration from a large (Ne⩾500) population in northwestern Russia could support the Fennoscandian metapopulation, but immigration must be substantial (5-10 effective immigrants per generation) and migration among Fennoscandian subpopulations must nevertheless increase.


Assuntos
Conservação dos Recursos Naturais/métodos , Genética Populacional/métodos , Densidade Demográfica , Lobos/genética , Animais , Fluxo Gênico , Depressão por Endogamia , Modelos Genéticos , Dinâmica Populacional , Países Escandinavos e Nórdicos
4.
Phys Rev Lett ; 93(20): 206803, 2004 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-15600953

RESUMO

The Cu adatom-induced localization of the two-dimensional Shockley surface state at the Cu(111) surface was identified from experimental and simulated scanning tunneling microscopy spectra. The localization gives rise to a resonance located just below the surface state band edge. The adatom-induced surface state localization is discussed in terms of the existence theorem for bound states in any attractive two-dimensional potential. We also identify adatom-induced resonance states deriving from atomic orbitals in both experimental and simulated spectra.

5.
Appl Opt ; 40(6): 969-73, 2001 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-18357081

RESUMO

We demonstrate the successful operation of a cw laser Doppler wind sensor at a wavelength of 1.55 mum. At longer ranges (>100 m) the signal conforms closely to complex Gaussian statistics, consistent with the incoherent addition of contributions from a large number of scattering aerosols. As the range is reduced, the probe volume rapidly diminishes and the signal statistics are dramatically modified. At the shortest ranges (<8 m) the signal becomes dominated by short bursts, each originating from a single particle within the measurement volume. These single-particle events can have a very high signal-to-noise ratio (SNR) because (1) the signal becomes concentrated within a small time window and (2) its bandwidth is much reduced compared with multiparticle detection. Examples of wind-signal statistics at different ranges and for a variety of atmospheric backscatter conditions are presented. Results show that single-particle-scattering events play a significant role even to ranges of ~50 m, leading to results inconsistent with complex Gaussian statistics. The potential is assessed for a low-power laser Doppler wind sensor that exploits the SNR enhancement obtained with single-particle detection.

6.
Appl Opt ; 39(21): 3716-26, 2000 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18349947

RESUMO

The design and performance of a simple, multifunction 1.55-mum continuous-wave (cw) and frequency-modulated cw coherent laser radar system with an output power of 1 W is presented. The system is based on a semiconductor laser source plus an erbium-doped fiber amplifier, a polarization-independent fiber-optic circulator used as the transmit-receive switch, and digital signal processing. The system is shown to be able to perform wind-speed measurements even in clear atmospheric conditions when the visibility exceeds 40 km. The aerosol measurements indicate the potential to use single-particle detection for wind measurements with enhanced sensitivity. The system can perform range and line-of-sight velocity measurements of hard targets at ranges of the order of several kilometers with a range accuracy of a few meters and a velocity accuracy of 0.1 m/s by use of triangular-wave frequency modulation with compensation of the frequency-modulation response of the semiconductor laser. The system also demonstrates a capability for vibration sensing.

7.
Appl Opt ; 38(15): 3376-86, 1999 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18319935

RESUMO

The performance of a frequency-modulated continuous-wave (FMCW) semiconductor laser radar has been examined. Frequency modulation (linear chirp) has been studied experimentally in detail. To create a linear frequency sweep, we modified the modulating function according to the measured frequency response of the laser, using an arbitrary function generator. The measurements indicate the possibility of achieving a spectral width of the signal peak that is transform limited rather than limited by the frequency modulation response of the laser, which permits the use of a narrow detection bandwidth. The narrow width results in a relatively high signal-to-noise ratio for low output power and thus also in relatively long-range and high-range accuracy. We have performed measurements of a diffuse target to determine the performance of a test laser radar system. The maximum range, range accuracy, and speed accuracy for a semiconductor laser with an output power of 10 mW and a linewidth of 400 kHz are presented. The influence of the laser's output power and coherence length on the performance of a semiconductor-laser-based FMCW laser radar is discussed.

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