Effects of galacto-oligosaccharides and a bifidobacteria lactis-based probiotic strain on the growth performance and fecal microflora of broiler chickens.

Jung, S J,Houde, R,Baurhoo, B,Zhao, X,Lee, B H Poultry Science Association, etc 2008 Poultry science Vol.87 No.9

<P>A galacto-oligosaccharide (GOS) prebiotic was prepared by reacting a high concentration of lactose (40% wt/vol) with a beta-galactosidase enzyme for 24 h at 37 degrees C. The enzyme was produced from recombinant Pichia pastoris X-33 cells. The study aimed at evaluating the effects of the prebiotic, a Bifidobacterium lactis-based probiotic, and the combination of these dietary additives on BW, feed intake, feed conversion ratio, and fecal counts of total anaerobic bacteria, lactobacilli, and bifidobacteria in broiler chickens. No significant differences in BW, feed intake and feed conversion ratio were found among the various groups. The study showed that GOS selectively stimulated the fecal microflora of broiler chickens. Total anaerobic bacteria and lactobacilli were increased by 3.4- and 3.56-fold, respectively, in chickens fed the diet containing GOS (3 kg per 25 kg) and B. lactis for 40 d compared with those fed the control diet. The bifidobacteria population in chickens fed the diet containing GOS (3 kg per 25 kg) and B. lactis significantly increased 21-fold in comparison to the control-fed birds. In particular, increasing the dietary concentration of GOS was accompanied by significant increases (P < 0.05) in bifidobacteria counts. The detectable population of bifidobacteria was also greater (P < 0.05) in chickens fed the diet containing GOS and bifidobacteria when compared with chickens fed a bifidobacteria-containing ration only. These results suggest that using GOS in combination with a B. lactis-based probiotic favored intestinal growth of bifidobacteria in broiler chickens.</P>

Statistical and Spectral Analysis of the BulbT Conical Diffuser Flow

Jean-David Buron,Sebastien Houde,Claire Deschenes 한국유체기계학회 2020 International journal of fluid machinery and syste Vol.13 No.1

The three dimensional unsteady swirling flow inside the draft tube of a model bulb turbine is investigated using timeresolved stereoscopic particle image velocimetry. The flow is analysed around the best efficiency points for twoN11 values. At N11 = 170, the draft tube flow dynamics are linked to a known efficency drop of the turbine while at N11 = 130, this phenomenon does not occur. This paper presents the experimental setup and provides a complete overview of the measurement campaign based on statistical and spectral analyses of the velocity fields and data from pressure sensors distributed across the draft tube. After the efficiency drop, the intermittency and skewness of the draft tube pressure recovery are found to be reflected onto the velocity fields. For both runner rotation speeds, spectral analyses reveal the presence of a coherent and non-axisymmetric structure that rotates at the same frequency as the runner.

Comparison of Anchovy Biomass Estimates Measured by Trawls, Egg Production Methods and Hydro-acoustics in the Chesapeake Bay and the Korea Strait

정석근,Edward D. Houde 한국해양과학기술원 2014 Ocean science journal Vol.49 No.2

We compared estimates of anchovy biomass derived from trawl surveys, egg production method (EPM) and acoustic surveys, conducted in two remote regions. Biomassdensity of bay anchovy Anchoa mitchilli was estimated in Chesapeake Bay, USA, by trawls, EPM and acoustics from 1989 to 2000. Biomass density of Pacific anchovy Engraulis japonicus was estimated in the Korea Strait using EPM, simulation-based daily cohort analysis and acoustics from 1984 to 2006. Most of the existing estimates already had considered body-size-dependent gear selectivity, highlyvariable instantaneous natural mortality of anchovy eggs, and avoidance of trawl nets by adult anchovy. Despite great variability in the ratio of trawl to acoustic biomass estimates (0.034-8.35), annually-averaged biomass density of young-ofthe-year individuals derived by the two methods were similar for bay anchovy in Chesapeake Bay and Pacific anchovy in the Korea Strait (0.83 and 0.70 g m-3, respectively). Results suggested that, despite substantial uncertainty, anchovy biomass estimates are generally compatible between EPM and acoustics. However, reported estimates of biomass density derived from the two acoustic surveys in the Korea Strait differed by a factor of 28, suggesting that further improvements in calibrations are required to reliably estimate anchovy biomass. The comparisons suggested that all biomass estimates could be biased and will require comparison and validation by other, independent sampling methods.

Two-photon absorption cross section of excited phthalocyanines by a femtosecond Ti-sapphire laser

Mir, Youssef,Van Lier, Johan E.,Allard, Jean-Francois,Morris, Denis,Houde, Daniel Korean Society of Photoscience 2009 Photochemical & photobiological sciences Vol.8 No.3

In the past few years, photodynamic therapy (PDT) has become a major treatment for neovascular age-related macular degeneration (AMD) in which there is abnormal growth of choroidal neovasculature (CNV) that eventually obscures central vision, leading to blindness. However, one of the main limitations of current PDT is the relatively low specificity of the photosensitizer (PS) and light for pathological tissue which may induce damage to adjacent healthy tissue. An alternative approach to circumvent the specificity limitation is to improve the irradiation process. In particular two photon (2-$\gamma$) excitation promises a more precise illumination of the target tissue. PS are activated by the simultaneous absorption of 2-$\gamma$ delivered by ultra-fast pulses of near infrared light. In order to evaluate the efficiency of phthalocyanine (Pc) dyes for 2-$\gamma$ absorption we measured 2-$\gamma$ absorption cross sections ($\sigma_2$) of a number of metalated Pc (MPc) dyes at $\lambda_{ex}$ = 800 nm using a femtosecond laser. The studied Pc molecules vary by the type of the central metal ion (Al or Zn) and the number of peripheral sulfo substituents (MPcS). Each MPc dye of our series shows an improved 2-$\gamma$ absorption $\sigma_2$ as compared to that obtained for Photofrin ($3.1{\pm}0.1\;GM$, with 1 GM = $10^{-50}\;cm^4\;s\;photon^{-1}\;mol^{-1}$), the PS currently approved for 1-$\gamma$ PDT. Our data show an 2.5-fold enhancement for AlPcCl, $AlPcS_{2adj}$ and $ZnPcS_3C_9$, up to 10-fold ($28.6{\pm}0.72\;GM$) for the ZnPcS4 dye relative to Photofrin. These findings confirm the efficiency of Pc for 2-$\gamma$ absorption processes and represent the first detailed comparison study of 2-$\gamma$ absorption $\sigma_2$ between Photofrin and Pc dyes.

Cerebrovascular Events in Older Patients With Patent Foramen Ovale: Current Status and Future Perspectives

Farjat-Pasos Julio I.,Chamorro Angel,Lanthier Sylvain,Robichaud Mathieu,Mengi Siddhartha,Houde Christine,Rodés-Cabau Josep 대한뇌졸중학회 2023 Journal of stroke Vol.25 No.3

Patent foramen ovale (PFO) closure, along with medical therapy, has emerged as the therapeutic gold standard in younger (<60-year-old) patients with a PFO-related stroke for preventing recurrent events. However, PFO management guidelines lack definite recommendations for older (>60 years) patients with a PFO-related cerebrovascular event, a complex group of patients who were mostly excluded from PFO closure clinical trials. Nevertheless, several studies have shown a higher prevalence of PFO among older patients with cryptogenic stroke, and its presence has been associated with an increased risk of recurrent events. Furthermore, older patients exhibit a higher prevalence of high-risk PFO anatomical features, present inherent age-related risk factors that might increase the risk of paradoxical embolism through a PFO, and have a higher incidence of ischemic events after a PFO-related event. Additionally, observational studies have shown the safety and preliminary efficacy of PFO closure in older PFO-related stroke patients. Yet, higher rates of recurrent cerebrovascular events and new-onset atrial fibrillation were observed in some studies among older patients compared to their younger counterparts. After careful case-by-case evaluation, including the assessment of hidden potential cardioembolic sources of a cryptogenic stroke other than PFO, transcatheter PFO closure might be a safe and effective therapeutic option for preventing recurrent thromboembolic events in patients >60 years with a high-risk PFO-associated stroke. Ongoing trials will provide important insights into the role of PFO closure in the elderly population.

Transcatheter Patent Foramen Ovale Closure in Stroke Patients with Thrombophilia: Current Status and Future Perspectives

Julio I. Farjat-Pasos,Jorge Nuche,Jules Mesnier,Vassili Panagides,Stephanie Cloutier,Christine Houde,Josep Rodés-Cabau 대한뇌졸중학회 2022 Journal of stroke Vol.24 No.3

Transcatheter patent foramen ovale (PFO) closure is a safe and effective treatment for secondary prevention after a PFO-associated stroke as demonstrated in multiple large randomized clinical trials. However, these trials excluded a significant proportion of patients who could have benefited from percutaneous PFO closure due to coexisting potential confounders such as additional thromboembolic risk factors, namely thrombophilia. Since scarce and conflicting data existed on such patients, current clinical management guidelines on patients with PFO mainly recommended against PFO closure in patients with thrombophilia and failed to provide any recommendation on the type and duration of antithrombotic treatment after transcatheter PFO closure. In the past 2 years, there has been new evidence supporting transcatheter PFO closure as a clinically meaningful alternative (vs. medical treatment) in this high-risk group of patients, along with additional data supporting the important role of systematic screening for thrombophilia in PFO-associated cerebrovascular events. This review article provides an updated overview of the incidence, clinical characteristics and outcomes of PFO closure in patients with thrombophilia, also commenting on the most appropriate medical treatment after PFO closure and future perspectives in the field.