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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065135

RESUMO

The Streaked Optical Pyrometer (SOP) is a visible diagnostic widely used to study the warm dense matter regime at high energy laser facilities, gas guns, or ion accelerators. It is usually coupled with a Velocity Interferometer System for Any Reflector (VISAR) diagnostic for simultaneous shock wave velocity, reflectivity, and temperature measurements to study the Equation of State (EOS) of materials. While VISAR is a well-mastered technology that provides velocity measurements with low relative uncertainties (close to percent), SOP diagnostics still suffer from high imprecision. In this article, we present a new calibration method in order to obtain absolute temperature measurements with reduced uncertainties. This approach is based on a novel light source: a Ce:YAG luminescent concentrator pumped by LEDs. This device produces enough optical power for calibration at the nanosecond sweep duration of the streak camera. As a demonstration, it has first been installed at the LULI facility and tested on quartz samples shocked at temperatures above 4000 K.

2.
Phys Rev Lett ; 126(8): 083603, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33709745

RESUMO

We demonstrate a source for correlated pairs of atoms characterized by two opposite momenta and two spatial modes forming a Bell state only involving external degrees of freedom. We characterize the state of the emitted atom beams by observing strong number squeezing up to -10 dB in the correlated two-particle modes of emission. We furthermore demonstrate genuine two-particle interference in the normalized second-order correlation function g^{(2)} relative to the emitted atoms.

3.
Animal ; 12(6): 1287-1295, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29143706

RESUMO

The perspective of a possible ban on surgical castration of male pigs in the EU is a real challenge for pork production systems aiming at (very) high-quality products. Information was collected from a total of 272 situations in 16 European countries, including 170 situations related to EU protected designations (Database of Origin & Registration (DOOR) database) and 102 other situations related to high-quality products or differentiated production systems, in order to evaluate their potential sensitivity to the use of entire male pigs along four dimensions: BT_Inc, likelihood of increased levels of boar taint compounds compared with conventional production of entire males; BT_Per, extent to which (some of) the associated pork product(s) are susceptible to perception of boar taint by consumers; FatQQ, likelihood that the quality of (some of) the related products is decreased due to the lower fat quantity and quality in entire males; Manag, increased likelihood of animal management and welfare problems compared with conventional production of entire males. Situations corresponding to EU protected designations (DOOR situations) were on average more sensitive to entire male production but 11% of the non-DOOR situations were highly potentially sensitive, whereas one-third of the DOOR situations had low potential sensitivity. In total, 37% of the situations where castration is not formally specified as mandatory exhibited high potential sensitivity to entire male production. Three main patterns of situations were identified via ascending hierarchical clustering. A first pattern including 31% of the DOOR situations and 74% of the other ones, had potentially no increased risk compared with conventional production of entire males. A second pattern including 28% of the DOOR situations and 16% of the other ones had a high, moderate and low potential sensitivity for FatQQ, BT_Inc and Manag, respectively. The third pattern including 41% of the DOOR situations and 11% of the other situations had high potential sensitivity for BT_Inc and FatQQ, associated with moderate to high sensitivity for Manag. The approach used to evaluate the sensitivity to entire male pig production from the limited information collected for this study has many limitations. More precise approaches using more specific information are needed to evaluate the actual sensitivity of individual situations to the use of entire male pigs. Still, the present study provides a first global insight on the capacity of European production systems aiming at high-quality products to use entire male pigs as an alternative to surgical castration.


Assuntos
Orquiectomia , Carne Vermelha , Suínos , Animais , Europa (Continente) , Masculino , Controle de Qualidade
4.
Meat Sci ; 137: 235-243, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29223558

RESUMO

A consumer study was performed in four EU countries to further clarify the acceptability of meat with boar taint. In Denmark, France, Italy and Poland, a total of 476 female consumers evaluated 8 meat patties from boars with varying levels of skatole (0.10-0.40µg/g fat tissue) and androstenone (0.47-2.00 µg/g fat tissue), in a pair-wise comparison with patties from castrates. Boar meat patties were always less preferred than the castrate meat patties, regardless of the level of androstenone and skatole. Acceptability of the boar meat patties decreased with increasing skatole level. In samples with low skatole levels, higher levels of androstenone also reduced acceptability among androstenone sensitive consumers. No clear threshold levels for androstenone and skatole could be identified. Maps presenting the reduction in preference due to increasing levels of skatole and androstenone, and corrected for the general acceptance of the meat product were developed, taking into account androstenone sensitivity. Further work is needed, covering the whole range of androstenone and skatole levels found in entire male pigs and for a wider set of meat products.


Assuntos
Comportamento do Consumidor , Carne Vermelha/análise , Adolescente , Adulto , Idoso , Androstenos/análise , Animais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia/veterinária , Escatol/análise , Olfato , Suínos , Paladar
5.
J Dent Res ; 96(12): 1406-1413, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28796952

RESUMO

Cell-based partial pulp regeneration is one of the promising approaches to obtain newly formed functional dentin-pulp complex. It relies on the preservation of the healthy tissue while regenerating the damaged pulp. The aim of this study was to investigate whether this regenerative process could be achieved by implanting porcine dental pulp cells (pDPCs) in pulp defects in the minipig. By split-mouth model, self-assembling injectable nanopeptide hydrogel, with and without pDPCs, was implanted after cameral pulpotomy in premolars and molars. At day 21 after surgery, 3-dimensional morphometric characterization, Masson's trichrome staining, and immunolabeling for DSP and BSP (dentin sialoprotein and bone sialoprotein) were performed on treated teeth. This study demonstrated no pulp regeneration but systematic reparative dentinogenesis. In fact, regardless of the presence of pDPCs in the scaffold, an osteodentin bridge-the microarchitecture of which significantly differed from the native dentin-was systematically obtained. Furthermore, the presence of pDPCs significantly affected the microstructure of the dentin bridges. In the radicular area of each treated tooth, hyperemia in the remaining pulp and external root resorptions were observed. Under the conditions tested in this work, pulp regeneration was not achieved, which highlights the need of further investigations to develop favorable regenerative microenvironment.


Assuntos
Polpa Dentária/citologia , Pulpotomia , Regeneração , Engenharia Tecidual/métodos , Animais , Proliferação de Células , Dentina Secundária/fisiologia , Proteínas da Matriz Extracelular/análise , Hidrogéis , Sialoproteína de Ligação à Integrina/análise , Fosfoproteínas/análise , Sialoglicoproteínas/análise , Coloração e Rotulagem , Suínos , Porco Miniatura , Microtomografia por Raio-X
6.
Sci Rep ; 6: 34187, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27725688

RESUMO

Quantum technologies will ultimately require manipulating many-body quantum systems with high precision. Cold atom experiments represent a stepping stone in that direction: a high degree of control has been achieved on systems of increasing complexity. However, this control is still sub-optimal. In many scenarios, achieving a fast transformation is crucial to fight against decoherence and imperfection effects. Optimal control theory is believed to be the ideal candidate to bridge the gap between early stage proof-of-principle demonstrations and experimental protocols suitable for practical applications. Indeed, it can engineer protocols at the quantum speed limit - the fastest achievable timescale of the transformation. Here, we demonstrate such potential by computing theoretically and verifying experimentally the optimal transformations in two very different interacting systems: the coherent manipulation of motional states of an atomic Bose-Einstein condensate and the crossing of a quantum phase transition in small systems of cold atoms in optical lattices. We also show that such processes are robust with respect to perturbations, including temperature and atom number fluctuations.

7.
Animal ; 8(12): 2047-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25222654

RESUMO

The aim of this paper is to present an efficient tool for evaluating the economy part of the sustainability of pig farming systems. The selected tool IDEA was tested on a sample of farms from 15 contrasted systems in Europe. A statistical analysis was carried out to check the capacity of the indicators to illustrate the variability of the population and to analyze which of these indicators contributed the most towards it. The scores obtained for the farms were consistent with the reality of pig production; the variable distribution showed an important variability of the sample. The principal component analysis and cluster analysis separated the sample into five subgroups, in which the six main indicators significantly differed, which underlines the robustness of the tool. The IDEA method was proven to be easily comprehensible, requiring few initial variables and with an efficient benchmarking system; all six indicators contributed to fully describe a varied and contrasted population.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Suínos , Animais , Europa (Continente)
8.
Animal ; 8(12): 2027-37, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25170767

RESUMO

Environmental impacts of 15 European pig farming systems were evaluated in the European Union Q-PorkChains project using life cycle assessment. One conventional and two non-conventional systems were evaluated from each of the five countries: Denmark, The Netherlands, Spain, France and Germany. The data needed for calculations were obtained from surveys of 5 to 10 farms from each system. The systems studied were categorised into conventional (C), adapted conventional (AC), traditional (T) and organic (O). Compared with C systems, AC systems differed little, with only minor changes to improve meat quality, animal welfare or environmental impacts, depending on the system. The difference was much larger for T systems, using very fat, slow-growing traditional breeds and generally outdoor raising of fattening pigs. Environmental impacts were calculated at the farm gate and expressed per kg of pig live weight and per ha of land used. For C systems, impacts per kg LW for climate change, acidification, eutrophication, energy use and land occupation were 2.3 kg CO2-eq, 44.0 g SO2-eq, 18.5 g PO4-eq, 16.2 MJ and 4.1 m2, respectively. Compared with C, differences in corresponding mean values were +13%, +5%, 0%, +2% and +16% higher for AC; +54%, +79%, +23%, +50% and +156% for T, and +4%, -16%, +29%, +11% and +121% for O. Conversely, when expressed per ha of land use, mean impacts were 10% to 60% lower for T and O systems, depending on the impact category. This was mainly because of higher land occupation per kg of pig produced, owing to feed production and the outdoor raising of sows and/or fattening pigs. The use of straw bedding tended to increase climate change impact per kg LW. The use of traditional local breeds, with reduced productivity and feed efficiency, resulted in higher impacts per kg LW for all impact categories. T systems with extensive outdoor raising of pigs resulted in markedly lower impact per ha of land used. Eutrophication potential per ha was substantially lower for O systems. Conventional systems had lower global impacts (global warming, energy use, land use), expressed per kg LW, whereas differentiated systems had lower local impacts (eutrophication, acidification), expressed per ha of land use.


Assuntos
Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Mudança Climática , Meio Ambiente , Suínos/fisiologia , Criação de Animais Domésticos/classificação , Animais , Conservação dos Recursos Naturais/métodos , União Europeia
9.
Animal ; 8(12): 2011-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25166005

RESUMO

Although a few studies consider the sustainability of animal farming systems along the three classical main pillars (economy, environment and society), most studies on pig farming systems address only one of these pillars. The present paper is the introduction to a series of companion papers presenting the results of a study undertaken within the EU-supported project Q-PorkChains, aiming at building a comprehensive tool for the evaluation of pig farming systems, which is robust to accommodate the large variability of systems existing in Europe. The tool is mostly based on questions to farmers and comprises a total of 37 dimensions distributed along eight themes: Animal Welfare, Animal Health, Breeding Programmes, Environmental Sustainability, Meat Safety, Market Conformity, Economy and Working Conditions. The paper describes the procedure that was used for building the tool, using it on 15 contrasted pig farming systems and analysing the results. The evaluated systems are briefly described and a short overview of the dimensions is provided. Detailed descriptions of the theme-wise tools and results, as well as the results of an integrated evaluation, are available in the companion papers.


Assuntos
Bem-Estar do Animal , Conservação dos Recursos Naturais/métodos , Abrigo para Animais/economia , Abrigo para Animais/normas , Suínos/fisiologia , Animais , Europa (Continente)
10.
Animal ; 8(12): 2058-68, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25166265

RESUMO

The aim of this paper is to present an approach for an integrated evaluation of the sustainability of pig farming systems, taking into account the three classical pillars: economy, environment and society. Eight sustainability themes were considered: Animal Welfare (AW), Animal Health (AH), Breeding Programmes (BP), Environment (EN), Meat Safety (MS), Market Conformity (MC), Economy (EC) and Working Conditions (WC). A total of 37 primary indicators were identified and used for the evaluation of 15 much contrasted pig farming systems in five EU countries. The results show that the eight themes were not redundant and all contributed to the observed variation between systems. The tool was very robust for highlighting the strengths and weaknesses of the systems along the eight themes that were considered. The number of primary indicators could be reduced from 37 to 18 with limited impact on the strengths/weaknesses profile of the individual systems. Integrating the eight theme evaluations into a single sustainability score is based on hypotheses or presumptions on the relative weights that should be given to the eight themes, which are very dependent on the context and on the purpose of the users of the tool. Therefore, the present paper does not have the ambition to provide a ready-for-use tool, rather to suggest an approach for the integrated evaluation of the sustainability of pig farming systems.


Assuntos
Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Bem-Estar do Animal/normas , Conservação dos Recursos Naturais/métodos , Suínos/fisiologia , Animais , Cruzamento , Meio Ambiente
11.
Animal ; 8(12): 2016-26, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25166468

RESUMO

The sustainability of breeding activities in 15 pig farming systems in five European countries was evaluated. One conventional and two differentiated systems per country were studied. The Conventional systems were the standard systems in their countries. The differentiated systems were of three categories: Adapted Conventional with focus on animal welfare, meat quality or environment (five systems); Traditional with local breeds in small-scale production (three systems) and Organic (two systems). Data were collected with a questionnaire from nine breeding organisations providing animals and semen to the studied farming systems and from, on average, five farmers per farming system. The sustainability assessment of breeding activities was performed in four dimensions. The first dimension described whether the market for the product was well defined, and whether the breeding goal reflected the farming system and the farmers' demands. The second dimension described recording and selection procedures, together with genetic change in traits that were important in the system. The third dimension described genetic variation, both within and between pig breeds. The fourth dimension described the management of the breeding organisation, including communication, transparency, and technical and human resources. The results show substantial differences in the sustainability of breeding activities, both between farming systems within the same category and between different categories of farming systems. The breeding activities are assessed to be more sustainable for conventional systems than for differentiated systems in three of the four dimensions. In most differentiated farming systems, breeding goals are not related to the system, as these systems use the same genetic material as conventional systems. The breeds used in Traditional farming systems are important for genetic biodiversity, but the small scale of these systems renders them vulnerable. It is hoped that, by reflecting on different aspects of sustainability, this study will encourage sustainable developments in pig production.


Assuntos
Criação de Animais Domésticos/normas , Bem-Estar do Animal , Cruzamento , Conservação dos Recursos Naturais/métodos , Suínos/genética , Suínos/fisiologia , Criação de Animais Domésticos/métodos , Animais , Europa (Continente) , Variação Genética , Humanos
12.
Theriogenology ; 79(1): 69-80, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23102848

RESUMO

The producer of vaccine against GnRH recommends that immunocastrated pigs are to be slaughtered within 4 to 6 weeks after the second vaccination (V2). The objective of the study was to examine the effect of shorter or longer delay on steroid hormones, boar taint compounds, and morphologic and histologic traits of reproductive organs. Forty male pigs (individually housed and fed a commercial diet) were assigned within litter to four treatment groups, 10 pigs were left entire (EM27) and the others were vaccinated against GnRH (Improvac, Pfizer Animal Health) at the age of 12 and 19 weeks. Pigs were slaughtered at 21 (IC21), 24 (IC24), and 27 (IC27 and EM27) weeks of age. Two EM27 pigs died during the experiment, one IC21 pig was excluded because of illness, one IC27 pig was a nonresponder, and two pigs (IC24 and IC27) were hermaphrodites. To assess the effect on steroid hormones, blood was taken at 12, 15, 19, 21, and 24 weeks of age. Subcutaneous fat and reproductive organs were sampled after slaughter for determination of androstenone, skatole, morphologic, and histologic measurements. Immmunocastration interrupted the rise of estrogen and caused a substantial fall of testosterone in IC21, IC24, and IC27 pigs. As a result, androstenone and skatole levels were successfully reduced regardless of the time elapsed from V2. The weight of the reproductive organs was also drastically reduced, the shrinkage being proportional to the length of the interval between V2 and slaughter and was the most evident for vesicular glands, followed by bulbourethral glands, and testes. Corresponding changes were observed also on a histologic level with a progressive decrease in the size and number of Leydig cells, a diminishing immunoreactivity of 3ß-hydroxysteroid dehydrogenase/Δ-5-4 isomerase, and luteinizing hormone receptor, along with a shrinkage of tubuli seminiferi, atrophy of seminiferous epithelium, and a loss of germ cells, indicating a disruption in testicular spermatogenetic function. Regression of the glandular tissue with a decreasing amount of secreta was also observed for bulbourethral and vesicular glands. The investigated physiologic, morphologic, and histologic traits were progressive with the increasing delay to slaughter (clearly seen already 2 weeks after V2), though no signs of functional or morphological restoration was observed within 8 weeks after V2.


Assuntos
Matadouros , Castração , Anticoncepção Imunológica/veterinária , Genitália/citologia , Hormônios Esteroides Gonadais/análise , Escatol/análise , Suínos/metabolismo , Androstenos/análise , Androstenos/metabolismo , Animais , Castração/métodos , Castração/veterinária , Anticoncepção Imunológica/métodos , Genitália/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Hormônio Liberador de Gonadotropina/imunologia , Masculino , Maturidade Sexual/fisiologia , Escatol/metabolismo , Suínos/fisiologia , Fatores de Tempo , Vacinas Anticoncepcionais/farmacologia , Vacinas Anticoncepcionais/uso terapêutico
13.
Animal ; 6(8): 1330-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23217237

RESUMO

Meta-analytical approach was used to quantitatively synthesize the effect of immunocastration on growth, carcass, meat quality, reproductive organs and boar taint compounds. Altogether, 41 papers were collected for effect size (θ) calculation and the comparisons were made with entire males (EM) and surgical castrates (SC). The data for reproductive organs and growth performance are numerous enough to draw firm conclusions. In contrast, data for carcass and meat quality are more limited. Results of meta-analysis show efficient immunocastration with the magnitude of the response being by far the largest for reproductive organs (θ = -2.8 to -5.0) and boar taint substances (θ = -2.8 and -0.8 for androstenone and skatole, respectively). However, compared with SC, the immunocastrates exhibit larger bulbourethral glands (θ = 1.3) and slightly higher concentrations of androstenone and skatole (θ = 0.1 and θ = 0.2, respectively). The impact of immunocastration is also remarkable on performance, where the main advantage of the immunocastrates is their boar-like performance until revaccination. In the period following the second vaccination, they eat much more than EM (θ = 2.1), resulting in large effect size for growth rate compared with both EM and SC (θ = 1.1 and θ = 1.4, respectively). Considering the whole fattening period, their feed conversion ratio is higher compared with EM (θ = 0.6) and much lower than that of SC (θ = -1.3), although exhibiting moderately faster growth compared with both (θ = 0.6 and θ = 0.2, respectively). With regard to carcass quality, the immunocastrates take intermediate position between EM and SC. Besides, our analysis suggests no difference in meat quality with SC and some meat quality advantages of immunocastrates over EM because of higher intramuscular fat content (θ = 0.4) and lower shear force (θ = -0.6).


Assuntos
Genitália Masculina/crescimento & desenvolvimento , Carne/normas , Orquiectomia/veterinária , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/cirurgia , Androsterona/metabolismo , Animais , Masculino , Orquiectomia/métodos , Escatol/metabolismo
14.
Phys Rev Lett ; 108(26): 260401, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23004939

RESUMO

The Cauchy-Schwarz (CS) inequality-one of the most widely used and important inequalities in mathematics-can be formulated as an upper bound to the strength of correlations between classically fluctuating quantities. Quantum-mechanical correlations can, however, exceed classical bounds. Here we realize four-wave mixing of atomic matter waves using colliding Bose-Einstein condensates, and demonstrate the violation of a multimode CS inequality for atom number correlations in opposite zones of the collision halo. The correlated atoms have large spatial separations and therefore open new opportunities for extending fundamental quantum-nonlocality tests to ensembles of massive particles.

15.
J Anim Sci ; 90(12): 4593-603, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22829612

RESUMO

The aim of this study was to assess the effect of feed restriction applied to immunocastrated pigs in the period after the second vaccination (V2) against GnRH on hormonal status, performance, carcass traits, and meat quality. Immunocastrated pigs (IC) were compared with entire males (EM) and surgical castrates fed ad libitum. Pigs (Large White × Landrace) × Pietrain were either left entire or surgically castrated within 1 wk after birth (SC, n = 22). At 83 d of age, the entire males were further allotted to treatment groups (individual housing) of ad libitum fed EM (n = 24), ad libitum fed IC (IC-L, n = 21), or restrictively fed IC (IC-R, n = 21). At that time, the first vaccination (V1) was applied to IC-L and IC-R pigs. One week after V2 (age 130 d), feed restriction (≈ 80% of the ad libitum feed intake of SC pigs) was applied to IC-R pigs. The experiment ended 5 wk after V2, when pigs were 165 d old. Immunocastration successfully reduced boar taint compounds and size of reproductive organs. At 130 d, serum leptin concentrations were similar in all groups, whereas IGF-I concentration was less in SC (P ≤ 0.002) than in the other groups. Three weeks after V2, leptin concentrations of both IC groups were in between EM (least) and SC (greatest). The reverse was observed for IGF-I. Feed restriction had no effect on leptin or IGF-I concentrations in IC pigs. In the period V1 to V2, performance differed mainly between EM and SC, whereas both IC groups had feed intake and feed conversion ratio similar to EM and intermediate daily BW gain, not differing from either EM or SC. After V2, IC-L pigs increased their feed intake to the concentrations of SC, with faster growth compared with the other 3 groups (P < 0.05) and fatter carcasses compared with EM pigs (P = 0.007). Similar performance and carcass leanness were observed for IC-R and EM pigs. During preslaughter handling more carcass lesions were noted in EM and IC-R than in IC-L or SC pigs (P < 0.002). Neither immunocastration nor feed restriction had any effect on meat quality, but EM had greater drip loss, less intramuscular fat, and decreased tenderness than SC pigs. In conclusion, restricting feed intake can increase production efficiency but also aggressiveness of IC pigs.


Assuntos
Carne/normas , Orquiectomia/veterinária , Animais , Composição Corporal , Privação de Alimentos , Genitália Masculina , Indóis , Masculino , Suínos/fisiologia , Vacinas
16.
Placenta ; 33(10): 769-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22831881

RESUMO

OBJECTIVES: Our objective was to evaluate the 3D power Doppler angiography (PDA) in terms of feasibility and ability to detect placental hypo-perfusion in an experimental rabbit model of intrauterine growth restriction (IUGR). STUDY DESIGN: 14 pregnant females were treated with NG-nitro-L-arginine methylester (L-NAME), a nitric oxide synthase inhibitor, from day 24 to day 28 of gestation, to induce an IUGR. Concomitantly, 8 pregnant rabbits were used as controls. On day 28, 3D power Doppler indices were quantified in each utero-placental unit. Morphological examination of the placentas for the control group (n = 4) and the L-NAME group (500 mg/day, n = 4) were performed with immunohistochemical staining to discriminate the fetal capillaries in the labyrinthine area. RESULTS: A total of 180 live fetuses were obtained, 108 from the L-NAME group and 72 from the control group. G28 fetal weight was significantly lower in the L-NAME group than in the control group (27.40 ± 0.55 g vs 33.14 ± 0.62 g, p < 0.0001). In the L-NAME group the vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were significantly lower than in the control group (2.6 [1.4; 6.0] vs 7.6 [3.5; 12.6], p < 0.05; 28.7 [26.5; 31.3] vs 32.9 [28.3; 38.1], p < 0.05; 0.8 [0.4; 1.8] vs 2.5 [1.1; 4.1], p < 0.05, for VI, FI and VFI, respectively). Morphological examinations revealed a substantial disorganization of the placental vascular architecture in the L-NAME group. CONCLUSION: This experimental study demonstrates that quantitative 3D PDA indices are sensitive enough to detect placental vascular insufficiency in an experimental rabbit model of IUGR.


Assuntos
Retardo do Crescimento Fetal/diagnóstico por imagem , Placenta/irrigação sanguínea , Animais , Modelos Animais de Doenças , Feminino , Imageamento Tridimensional/métodos , NG-Nitroarginina Metil Éster , Placenta/diagnóstico por imagem , Placenta/efeitos dos fármacos , Circulação Placentária/efeitos dos fármacos , Gravidez , Coelhos , Ultrassonografia
17.
Rev Sci Instrum ; 83(4): 044705, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22559563

RESUMO

We present a rf gas discharge apparatus which provides an atomic frequency reference for laser manipulation of metastable helium. We discuss the biasing and operation of a Colpitts oscillator in which the discharge coil is part of the oscillator circuit. Radiofrequency radiation is reduced by placing the entire oscillator in a metal enclosure.

18.
Meat Sci ; 90(2): 330-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21862238

RESUMO

Consumer acceptability of entire male pork at eating was assessed in three experiments. The 140 consumers involved in each experiment were classified as insensitive (INSENS) to the odor of pure androstenone or sensitive perceiving it as pleasant (SENS-PLEA) or unpleasant (SENS-UNPL). Entire male pork with very low skatole and androstenone levels (LS-LA) was as well accepted as gilt pork, whatever the consumer category. Entire male pork with elevated levels in both skatole and androstenone (HS-HA) was clearly differentiated from LS-LA pork by SENS-UNPL, but not by SENS-PLEA or INSENS consumers. Whatever the consumer category, entire male pork with elevated levels of androstenone and very low levels of skatole (LS-HA and LS-HHA) were not significantly differentiated from LS-LA pork. The results suggest that, in the conditions of the present experiment, androstenone and skatole totally explain boar taint at eating and that the acceptability threshold for androstenone, in the absence of skatole, is in the range of 2-3 µg/g liquid fat.


Assuntos
Androsterona/análise , Comportamento do Consumidor , Carne , Odorantes/análise , Escatol/análise , Adolescente , Adulto , Animais , Feminino , Análise de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Olfato , Suínos , Limiar Gustativo , Adulto Jovem
19.
Phys Rev Lett ; 109(22): 220401, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23368107

RESUMO

We have modulated the density of a trapped Bose-Einstein condensate by changing the trap stiffness, thereby modulating the speed of sound. We observe the creation of correlated excitations with equal and opposite momenta, and show that for a well-defined modulation frequency, the frequency of the excitations is half that of the trap modulation frequency.

20.
J Fr Ophtalmol ; 34(10): 715-22, 2011 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21907448

RESUMO

PURPOSE: To assess the relationship and respective contribution of ocular higher-order aberrations (HOAs) on residual accommodative performance in presbyopic patients. PATIENTS AND METHODS: We enrolled 20 patients (40 eyes) without ophthalmological pathology, between 48 and 58 years old, with a best-corrected visual acuity more than 10/10. Total aberrations were computed using the Wavescan Aberrometer (AMO, USA). The defocus curve and near visual acuity (30 and 50 cm) were measured. The relationship between accommodation ability and HOAs was evaluated aiming at a linear relationship with a simple regression analysis and with a multiple linear regression analysis (including manifest refraction, ocular aberrations, and age). RESULTS: Even if age and manifest refraction were correlated with accommodative ability, ocular coma seemed to be correlated with near visual acuity without addition and with minimal addition for reading P1.5 at 30 cm (respectively, r(2)=0.117 with P=0.035 and r(2)=0.163 with P=0.012). Total spherical aberration appeared to be correlated with minimal addition (r(2)=0.12 with P=0.032). DISCUSSION: Ocular aberrations (coma and spherical aberration) are correlated with accommodative performance in presbyopic patients, independently of age and manifest refraction. CONCLUSION: Ocular aberrations appeared to be a stimulus for accommodation but may also influence quality of accommodative reply.


Assuntos
Acomodação Ocular/fisiologia , Presbiopia/complicações , Presbiopia/fisiopatologia , Transtornos da Visão/etiologia , Acuidade Visual/fisiologia , Fatores Etários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Presbiopia/epidemiologia , Refração Ocular/fisiologia , Índice de Gravidade de Doença , Transtornos da Visão/complicações , Transtornos da Visão/diagnóstico , Transtornos da Visão/epidemiologia , Testes Visuais
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