Adsorption of methylene blue on activated carbon xerogels

Poster (2011, November 30)

Caractérisation microstructurale de mousses polymères nanocomposites par microtomographie à rayons X

Poster (2011, November 29)

Les circuits électriques, fonctionnant à des fréquences de plus en plus élevées, sont responsables de l’augmentation de la pollution électromagnétique, et justifient le développement de blindages ... [more ▼]

Les circuits électriques, fonctionnant à des fréquences de plus en plus élevées, sont responsables de l’augmentation de la pollution électromagnétique, et justifient le développement de blindages efficaces. De nombreuses applications sont concernées, que ce soit dans les systèmes électroniques commerciaux, industriels, ou militaires, ou les systèmes antennaires. Récemment, des blindages sous forme de composites polymère/charges carbonées ont été largement développés pour leur nombreux avantages : plus légers, moins chers, plus absorbants, et plus facilement moulables. Une charge carbonée prometteuse est le nanotube de carbone car de par son facteur de forme, une concentration moindre est nécessaire pour une conductivité équivalente [1]. Afin d’améliorer l’absorption de l’énergie électromagnétique de ces composites (par rapport à leur réflectivité), ils sont moussés pour réduire leur constante diélectrique. Cette étape de moussage doit être rigoureusement contrôlée pour atteindre le niveau d’absorption ciblé. Deux techniques de moussage sont envisagées dans cette étude, à savoir le moussage en CO2 supercritique (par imprégnation de CO2 en condition supercritique, avant une dépressurisation rapide) et le freeze-drying (dissolution dans un solvant, suivi d’une lyophilisation de celui-ci). Ces deux méthodes génèrent des structures de porosité bien distinctes, avec une anisotropie apparente marquée dans le second cas. L’objectif est de caractériser ces structures par tailles moyennes de pores et mesures d’anisotropie, et leur lien avec l’efficacité de blindage. Dans cette optique, la caractérisation est effectuée par microtomographie à rayons X, une technique d’imagerie 3D non-destructive. Des acquisitions sont faites sur chaque échantillon, et la microstructure est analysée par traitement d’images. Vu la très faible atténuation des rayons X dans ce type de matériaux, et la limite de résolution de cette technique par rapport à la taille des pores et à l’épaisseur des parois, la séparation précise des pores par rapport à la matrice polymère s’avère difficile. Une segmentation classique n’étant pas applicable en préalable à des mesures quantitatives, la fonction d’autocorrélation est utilisée. Cette technique, habituellement utilisée en traitement du signal, est une méthode performante de mesure globale de l’anisotropie d’un matériau [2]. Elle permet également d’extraire une longueur caractéristique qui peut être liée à la taille des cellules. Les résultats mettent en évidence l’impact de la technique et des conditions de moussage sur la microstructure des mousses composites. [less ▲]

A Brain-Machine Interface Operating with a Real-Time Spiking Neural Network Control Algorithm

Poster (2011, November 29)

Motor prostheses aim to restore function to disabled patients. Despite compelling proof of concept systems, barriers to clinical translation remain. One challenge is to develop a low-power, fully ... [more ▼]

Motor prostheses aim to restore function to disabled patients. Despite compelling proof of concept systems, barriers to clinical translation remain. One challenge is to develop a low-power, fully-implantable system that dissipates only minimal power so as not to damage tissue. To this end, we implemented a Kalman-filter based decoder via a spiking neural network (SNN) and tested it in brain-machine interface (BMI) experiments with a rhesus monkey. The Kalman filter was trained to predict the arm’s velocity and mapped on to the SNN using the Neural Engineering Framework (NEF). A 2,000-neuron embedded Matlab SNN implementation runs in real-time and its closed-loop performance is quite comparable to that of the standard Kalman filter. The success of this closed-loop decoder holds promise for hardware SNN implementations of statistical signal processing algorithms on neuromorphic chips, which may offer power savings necessary to overcome a major obstacle to the successful clinical translation of neural motor prostheses. [less ▲]

Communication du médecin centrée sur le patient: Intérêt pour l'équipe pluridisciplinaire

Poster (2011, November 25)

INTRODUCTION. Deux types de communication existent entre les médecins et les patients. La première, traditionnelle, s’appelle la communication centrée sur le médecin. La seconde, plus récente, s’intitule ... [more ▼]

INTRODUCTION. Deux types de communication existent entre les médecins et les patients. La première, traditionnelle, s’appelle la communication centrée sur le médecin. La seconde, plus récente, s’intitule la communication centrée sur le patient. Dans ce type de communication, les médecins adoptent des comportements qui favorisent notamment l’expression du patient. C’est pourquoi, nous nous sommes interrogés sur l’intérêt d’une telle communication en oncologie, tant du point de vue du patient que de celui des membres des équipes pluridisciplinaires. METHODOLOGIE. Dans une étude antérieure, une formation de base à la communication a été donnée à 63 médecins ; cette formation se définissait en termes de stratégies d’évaluation de l’état psychologique du patient mais également en termes de stratégies de soutien vis-à-vis du patient. Pour alimenter notre discussion sur la pertinence de former des médecins à une communication centrée sur le patient, nous avons retenu, d’une part, l’indice de Karnofsky (caractéristique physique du patient), et d’autre part, les scores de dépression, d’anxiété, de détresse et de qualité de vie (QV) (caractéristiques psychologiques du patient). Le principal outil écologique utilisé est l’Inventaire Systémique de Qualité de Vie (ISQV-©). RESULTATS. Avant la formation de base à la communication, il n’y a aucune corrélation significative entre les compétences de communication du médecin (évaluation et soutien) et les caractéristiques du patient (physique et psychologiques). Après la formation à la communication, deux corrélations sont significatives : les médecins utilisent davantage de stratégies d’évaluation avec les patients dont l’état actuel (en termes de QV) est médiocre et avec les patients dont le but idéal est trop éloigné de leur état actuel. CONCLUSION. Ces résultats tendent à montrer que les corrélations obtenues entre les compétences d’évaluation des médecins et les scores d’état et de but du score de QV des patients sont davantage le reflet d’une communication centrée sur le patient. Ainsi, à l’intérieur d’un entretien médical (l’annonce d’un diagnostic), des affects d’ordre psychologique ont pu émerger. La question qui se pose alors en équipe pluridisciplinaire est de réfléchir à l’exploitation de ces nouvelles données : que fait-on de ce matériel psychologique, qui s’en occupe et comment ? Il s’agit là des prémisses d’une communication transdisciplinaire. [less ▲]

Design of reversibly disulfide core cross-linked polymer micelles

Poster (2011, November 21)

Over the last decade, polymer micelles attracted an increasing interest in drug pharmaceutical research because they could be used as efficient drug delivery systems. Micelles of amphiphilic block ... [more ▼]

Over the last decade, polymer micelles attracted an increasing interest in drug pharmaceutical research because they could be used as efficient drug delivery systems. Micelles of amphiphilic block copolymers are supramolecular core-shell type assemblies of tens of nanometers in diameter. An accumulation of polymer nanocarriers to solid tumours is possible due to the EPR effect. Even if micelles get a high stability in aqueous media, the dissociation of micelles is not always preserved when they are injected in the blood compartment. This work aims at reporting on the design of reversibly cross-linked micelles based on PEO-b-PCL copolymers by introducing disulfide bridges in the micelle core to provide higher stability. Different kinds of macromolecular architectures are employed to study their impact on the micelles and their biological behavior. These new functional copolymers were all successfully micellized, reversibly cross-linked and are stealthy, which show the efficiency of the developed cross-linking process and offer a set of nanocarriers to be tested further, as shown on the first biological tests. [less ▲]

Smart block copolymers for biomedical applications

Poster (2011, November 21)

Smart polymers are polymers that respond with rapid changes to external stimuli such as pH, temperature, light or ionic strength. Responses to the stimuli may manifest themselves as changes in solubility ... [more ▼]

Smart polymers are polymers that respond with rapid changes to external stimuli such as pH, temperature, light or ionic strength. Responses to the stimuli may manifest themselves as changes in solubility, shape or surface characteristics. These materials are very intersesting for different biomedical applications such as drug delivery systems, tissue engineering or sensors. In this work, we focused on two separate systems: on the one hand, micelles and, on the other hand, iron oxide nanoparticles. These nanoparticles are generally synthesized in a one-step process by alkaline coprecipitation of iron (II) and iron (III) precursors. However, iron oxide nanoparticles are not stable enough in physiological conditions to be used as is. A stabiliser coating is needed to avoid aggregation and precipitation of the colloids in body fluids. For this coating, the polymer blocks chosen are PEO (to confer stealthiness), PAA (pH-responsive) and PNIPAM (thermoresponsive). This triblock copolymer was synthesized by RAFT polymerization and was used alone to form micelles and with iron oxide to make magnetic stabilized nanoparticles. The behaviour of micelles and coated nanoparticles was investigated by a combination of DLS, TEM and zeta potential measurements. To highlight the potentiality of these nanomaterials, their cytotoxicity will be studied and compared. [less ▲]

Chitosan-based nanofibers with multilayered structure for wound healing application

Poster (2011, November 21)

Chitosan is a natural polymer that intrinsically presents haemostatic, mucoadhesive, antimicrobial and immunostimulant properties. This polysaccharide has shown a great potential for biomedical ... [more ▼]

Chitosan is a natural polymer that intrinsically presents haemostatic, mucoadhesive, antimicrobial and immunostimulant properties. This polysaccharide has shown a great potential for biomedical applications, on account of its remarkable compatibility with physiological medium and its biodegradability. In this respect, nanometric fibers are highly interesting as their assembly mimics the skin extracellular matrix structure. Such nanofibrous materials can be prepared by electrospinning (ESP) and can be used as scaffolds, a.o. to form a temporary, artificial extracellular matrix. In the present study, electrospinning technique was combined with layer-by-layer deposition method (LBL) – a well-known method for surface coating, based on electrostatic interactions – in order to prepare multilayered chitosan-based nanofibers for wound healing application. [less ▲]

Investigations on the mechanisms underlying the thymotropic properties of the growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis.

Poster (2011, November 18)

Background. The thymus is responsible for thymopoiesis, i.e. the generation of a diverse and self-tolerant T-cell repertoire including self-antigen specific natural regulatory cells. We have shown that ... [more ▼]

Background. The thymus is responsible for thymopoiesis, i.e. the generation of a diverse and self-tolerant T-cell repertoire including self-antigen specific natural regulatory cells. We have shown that two parameters of thymopoiesis, thymic output of new T cells (estimated by sjTREC frequency) and intrathymic proliferation of T-cell precursors (estimated by sj/Dβ TREC ratio) are severely reduced in adult patients with GH deficiency (AGHD) and are restored by GH injections at physiological doses. In patients with AGHD, there is a very positive correlation between sjTREC frequency and plasma concentrations of IGF-1, the principal mediator of GH action (1). Treatment of HIV+ patients with high pharmacological doses of GH is associated with increased thymic mass and output of circulating naïve and total CD4+ T cells (2). In addition, previous studies have suggested thymic epithelial cells (TEC) and/or thymocytes (thymic T cells) could transcribe the GH gene (3). Objectives and hypothesis. These studies analysed the question of GH transcription and regulation in primary cultures of human (h) TEC. We also investigated the hypothesis that the thymotropic properties of the somatotrope GH/IGF-1 axis could be mediated by thymic interleukin 7 (IL-7), which plays a crucial role in promoting V(D)J recombination at the TCR locus. Results. Primary hTEC cultures were treated with natural secretagogues of pituitary GH, GH releasing hormone (GHRH) and ghrelin. Using sensitive RT-qPCR, we detected neither any transcript of GH or GHV (placental GH variant) in cultured hTEC, nor any transcript of PIT1, the specific transcription factor of pituitary GH. Similarly, the protein GH was detected neither in the cytoplasm nor in the supernatant of cultured hTEC. Only at 1 nM, GH treatment enhanced IGF1 transcription by cultured hTEC. Of high interest, treatment with GH, ghrelin and IGF-1 promoted IL7 transcription by cultured hTEC, but only IGF-1 and epidermal growth factor (EGF) markedly stimulated IL-7 secretion by hTEC in a dose- and time-dependent manner. The specificity of IGF-1 action was demonstrated by its inhibition after treatment with αIR3, a monoclonal antibody against the type 1 IGF receptor. Conclusions and perspectives. Since primary cultures of hTEC neither transcribe nor secrete any significant amount of GH, the thymotropic effects of the GH/IGF-1 axis seem to depend only on systemic endocrine GH. Local thymic IGF-1 could partially mediate GH action within the thymus and act upon thymopoiesis in parallel with systemic IGF-1. Most importantly, thymic IL-7 appears to be an important mediator of the thymotropic properties of the GH/IGF-1 axis. Further knowledge in this domain will be gained with the use and supplementation of Ghrh-/- mice that will be soon available in our laboratory. References 1. Morrhaye G. et al., PLoS ONE 2009, 4:e5668. 2. Napolitano LA et al. J Clin Invest 2008, 118:1085. 3. Smaniotto S et al., Endocrinology 2005, 146:3005. 4. Taub DD, Murphy WJ and Longo DL. Curr Opin Pharmacol 2010, 10:408. (Supported by F.R.S.-FNRS and a Pfizer Independent Research Grant.) [less ▲]

In vitro evaluation of the prebiotic potential of new carbohydrates extracted from agro-industrial byproducts

Poster (2011, November 17)

In vitro evaluation of the prebiotic potential of new carbohydrates extracted from agro-industrial byproducts

Poster (2011, November 16)

Replacement of goal-tracking by sign-tracking under reward uncertainty, and impairment by dopamine antagonism in the rat

Poster (2011, November 16)

Hypothesis: uncertainty influences Pavlovian reward prediction by arousing incentive motivation for reward (or ‘wanting’), expressed as sign-tracking (ST) or goal-tracking (GT) responses in an autoshaping ... [more ▼]

Hypothesis: uncertainty influences Pavlovian reward prediction by arousing incentive motivation for reward (or ‘wanting’), expressed as sign-tracking (ST) or goal-tracking (GT) responses in an autoshaping paradigm. Here we investigated the effect of 3 types of uncertainty: 1) reward probability (UCS occurred after CS+ under 50% probability), 2) uncertainty about reward magnitude (UCS was 1, 2, or 3 sucrose pellets), and 3) uncertainty resulting from a combination of both conditions. We also tested the effects of reversal learning (shift in reward probability from 100 to 50%) and systemic dopamine blockade under uncertainty (flupenthixol, i.p.) on acquisition of autoshaping. [less ▲]

Innocent but paternalistic comments as interference that strikes hard on women

Poster (2011, November 14)

BINDING INTERACTIONS OF URONIC ACID DERIVATIVES TO LIPID VESICLES INVESTIGATED BY ISOTHERMAL TITRATION CALORIMETRY

Poster (2011, November 12)

Uronic acid derivatives (UAD) constitute a particular class of carbohydrate-based small compounds, which are receiving growing interests today for many reasons. Beyond their excellent environmental ... [more ▼]

Uronic acid derivatives (UAD) constitute a particular class of carbohydrate-based small compounds, which are receiving growing interests today for many reasons. Beyond their excellent environmental compatibility, their potentiality mainly arises from the large abundance of their precursors from renewable resources, and the quasi-unlimited availability of their molecular structure and geometry [1]. Such a structural diversity allows them to be a typical compound class for the structure-activity relationship investigation using simplest models. This approach is very important for predicting their functionalities and activities. Among others, searching specific and potent biological activities against target molecules, cells, and micro-organisms is a big challenge today. In this context, binding interactions of three UAD having different hydrophobic residues (allyl, benzyl, and cyclohexyl) to 1-palmitoyl-2-oleyl-sn-glycerol-3-phosphatidylcholine (POPC) vesicles have been investigated using Isothermal Titration Calorimetry (ITC) technique [2]. The binding affinity (Ka) to the membrane model at 25°C has been determined and compared for the three compounds. Based on thermograms resulting from UAD aqueous solution titration experiments, with and without POPC vesicles, it clearly appears that both derivatives with a cyclic residue interact stronger with the lipid membrane model than their linear derivative counter-part, which exhibits almost no interaction. Moreover, the derivative compound with a cyclohexyl residue saturates faster POPC vesicles than that with a benzyl residue. We conclude that: (a) UAD having a cyclic hydrophobic residue, either saturated or unsaturated, bind more easily to the lipid membrane model than a linear one ending with a double bond; (b) the greater the number of hydrogen in the UAD residue chemical structure (saturated bonds), the stronger their binding affinity to POPC vesicles, suggesting the importance of H-bonding to such a lipid membrane model. The Ka mean value of the best tested UAD, i.e. with a cyclohexyl residue, is about 5.103 M-1. [1] Razafindralambo, H.; Blecker, C; and M. Paquot., Screening of basic properties of amphiphilic molecular the structures for colloidal system formation and stability: the case of carbohydrate-based surfactants in: Amphiphiles: Molecular Assembly and Applilcations, ed. R. Nagarajan, ACS, Washignton, 2011, (In press). [2] Razafindralambo, H.; Dufour, S.; Paquot, M.; Deleu, M., Thermodynamic studies of the binding interactions of surfactin analogues to lipid vesicles: application of isothermal titration calorimetry. J. Therm. Anal. Calorim., 2009, 9 (3), 817-821. Acknowledgment: This work was supported by Belgian Walloon Region with DG06 research project of excellence (TECHNOSE). [less ▲]

Environmental impact of photovoltaic power by Life Cycle Assessment

Poster (2011, November 03)

Life cycle assessment of carbon xerogels

Poster (2011, November 03)

A web-based framework for visualization, annotation, and automatic exploitation of high-resolution bioimages using tree-based machine learning methods

Poster (2011, November 02)

Retour au travail en cas d'arrêt-maladie de longue durée, le point de vue du patient

Poster (2011, November)

Introduction Face à l’enjeu du maintien dans l’emploi en cas de problème de santé, le médecin du travail et le médecin-conseil de sécurité sociale peuvent jouer un rôle important, mais qu’en pense le ... [more ▼]

Introduction Face à l’enjeu du maintien dans l’emploi en cas de problème de santé, le médecin du travail et le médecin-conseil de sécurité sociale peuvent jouer un rôle important, mais qu’en pense le patient ? L’étude avait donc pour objectif d’explorer le point du vue du patient afin d’identifier les obstacles et les éléments facilitateurs sur lesquels ces médecins peuvent s’appuyer pour promouvoir le retour au travail. Méthodologie L’étude a comporté l’interview téléphonique de 100 patients recrutés via deux organismes assureurs. Les critères d’inclusion étaient : être en arrêt de travail de longue durée (3 mois< arrêt < 8 mois), bénéficier d’une surveillance de santé en médecine du travail, et accepter de participer à l’étude. Résultats Les principales causes des absences sont les affections mentales (21%), les pathologies rachidiennes (11%) et les traumatismes (16%). Pour pouvoir retourner au travail, 40% des répondants disent attendre un effet du traitement ou une amélioration de leur état et 62% désignent le manque d’amélioration ou l’aggravation de celui-ci comme facteur freinant leur reprise. Un autre facteur est le manque de compréhension des collègues et/ou du chef hiérarchique. La majorité des répondants estiment qu’un travail adapté (diminution de la charge de travail ou des heures prestées, adaptation des horaires,…) faciliterait la reprise. Les répondants ont une perception plutôt négative du médecin du travail: la visite périodique est décrite comme superficielle et brève et peu connaissent le rôle du médecin. La plupart des répondants accepteraient que les médecins en charge de leur dossier se concertent à leur sujet mais s’interrogent quant à l’utilité d’un tel échange. Conclusions L’aide que le médecin du travail peut apporter au patient pour la reprise de travail est largement ignorée et de nombreux obstacles entravent les possibilités de coopération entre médecin du travail et médecin-conseil pour favoriser le maintien dans l’emploi. [less ▲]

Use of Bacillus subtilis S499 to control mould growth during malting of red sorghum from the D.R. of Congo

Poster (2011, November)

In this work, moulds growth was monitored during malting of a red sorghum from D.R. of Congo. Results obtained with chemical treatments [diluted alkalines: NaOH 0.2% (T1) and Ca(OH)2 0.1% (T2)] were ... [more ▼]

In this work, moulds growth was monitored during malting of a red sorghum from D.R. of Congo. Results obtained with chemical treatments [diluted alkalines: NaOH 0.2% (T1) and Ca(OH)2 0.1% (T2)] were compared with those of biocontrols [use of Bacillus subtilis S499 108 cells / mL: supernatant + cells (T3), cells (T4) and cells-free supernatant (T5)]. Chemical treatments have shown the highest fungal contamination levels, the highest malting loss, but better enzyme activities (α and β-amylases, limit-dextrinase, α-glucosidase and β-glucanase). The inhibition tests showed that the concentration of lipopeptides is correlated with the reduction of moulds growth. Malting trials with starters of Bacillus subtilis S499 showed that culture dilution affects the growth of moulds during red sorghum malting. The combination of a chemical treatment such as diluted NaOH with a biocontrol could be used to improve sorghum malts quality in terms of different enzymes activities and by reducing the level of fungal contamination. Key words: Bacillus subtilis S499, mould, sorghum malting [less ▲]

Reproductive impact and proteomic analysis of androgenic and anti-androgenic disruptors on the hermaphroditic freshwater gastropod Lymnaea stagnalis

Poster (2011, November)

In this study, e ects of two androgens (tributyltin and testosterone), one antiandrogen (cyproterone acetate) and one estrogen (chlordecone) on growth and reproduction were investigated in the ... [more ▼]

In this study, e ects of two androgens (tributyltin and testosterone), one antiandrogen (cyproterone acetate) and one estrogen (chlordecone) on growth and reproduction were investigated in the hermaphrodite gastropod Lymnaea stagnalis. In this study, exposure to a range of concentrations (ng/l to μg/l) of each chemical was performed during 21 days. e number of clutches and the number of eggs per clutch were monitored. A decrease in clutches laid per snail was observed after exposure to tributyltin (540, 1180 and 2600 ng/l) and chlordecone (10, 22, 50 and 110 μg/l). A signi cant decrease in egg laid per snail was observed after exposure to tributyltin (540, 1180 and 2600 ng/l) and chlordecone (50 and 110 μg/l). An increase of egg abnormalities ratio in exposed snails (atrophied albumen, polyembryonicity,...) was observed in L. stagnalis following exposure to testosterone (2, 22, 50 and 110 ng/l), cyproterone acetate (4,5 and 50 μg/l), tributyltin (110 and 244 ng/l) and chlordecone (4,5 and 10 μg/l). Investigation of alteration in protein expression in exposed snails was performed using proteomic analysis such as 2D-DIGE. Mass spectrometry identi cation was performed on proteins with altered expression. We could establish correlation between reproductive endpoints and changes in proteins involved in egg formation and in egg laying were underlined. Egg yolk ferritin, the main protein of egg yolk, was shown to be reduced signi cantly in relationship with a decrease of egg yolk quality after exposure to tributyltin 540 ng/l and cyproterone acetate 4,5 μg/l. Ovipostatin, a protein proved to reduce egg masses, was signi cantly over expressed in snails exposed to 50 μg/l of chlordecone and were in relationship with a reduction of clutches laid by individuals. Further western blot analysis on those proteins involved in the reproduction are underway. ese analysis will enable us to con rm and re ne with more speci city the 2D-DIGE results for the selected proteins. e results of this study can help to establish new biomarkers of exposure of endocrine disruptors in freshwater environment and can provide new insight on mode of action of endocrine disruptors in L. stagnalis. [less ▲]

Determination of optimum conditions for preservation and reactivation of freeze-dried Acetobacter senegalensis used as vinegar starter

Poster (2011, November)

Availability of efficient starters is one of the most important elements during fermentation technology. Acetic acid bacteria (AAB) face extreme conditions (low pH, high acetic acid concentration (>7 ... [more ▼]

Availability of efficient starters is one of the most important elements during fermentation technology. Acetic acid bacteria (AAB) face extreme conditions (low pH, high acetic acid concentration (>7%), ethanol and high temperature) during vinegar fermentation. In spite of introduction of broth media contained viable AAB as starter by some companies; traditional methods for initiation of vinegar fermentation are still used even in modern factories, therefore there is a long Lag phase for initiation of fermentation. In recent studies in CWBI, a kind of lyophilized starter has been produced by using an isolated thermotolerant bacterium: Acetobacter senegalensis. The aim of this study is to determine the best media for revitalization and the optimum temperature for preservation of the freeze-dried cells. To produce biomass, glucose was used as carbon source in batch culture under regulated conditions. The cells harvested when they reached to stationary phase. Harvested cells suspended in spent growth medium (final supernatant of fermentation). Maltodextrin (10%), manitol (20%) and spent growth medium were used as protestants. After freeze-drying they were subjected to storage test at -20° C, 4° C and 35° C for six months. The viability of cells determined by using spread plate technique using three different media: YG (yeast extract, glucose) and YGE (yeast extract, glucose, ethanol) and YGEA (yeast extract, glucose, ethanol, acetic acid). According to residual viable cells, manitol and maltodextrin showed higher protective functions rather than spent growth medium (92.3%, 88.2% and 82.1% survival, respectively) during freeze-drying process. Viability of cells during rehydration is completely dependent to the composition of the broth media used for this purpose. Adding ethanol (>0.5%) or acetic acid (>1%) to rehydration medium caused 40-45% reduction in viable cell numbers in comparison to YG broth. The composition of culture media can also influence the growth of bacteria after rehydration. In YG, much higher cell growth (about 1 log unit) was observed in comparison to YGE and YGEA. Addition of glucose (20 g/l) to YGE can neutralize the adverse effect of ethanol considerably but it cannot improve the growth in YGEA. This can be partially explained according to the activity of alcohol dehydrogenase and acetaldehyde dehydrogenase. It was revealed that freeze-dried cells had very low activities for these two enzymes. Analysis of total soluble protein contents of lyophilized cells during storage at different conditions revealed that the soluble protein content of cells reduced by increasing the storage temperature. At 35° C after 15 days, there were 4.87 log units reduction in the viability of cells, and also about 14% less soluble protein was detectable under this condition whereas keeping of cells at -20 or + 4° C had no influences on protein and viability of cells. Storage of cells at +4° C in darkness for six month showed that about 79.2% and 68.3% viability of cells remained for cells protected by manitol and maltodextrin, respectively. To assess the real activity of lyophilized cells as starters, they were introduced to broth media (YGE contained 20g/l of glucose). It was seen that 6 months old lyophilized cells (with maltodextrin or manitol as protectants) were able to grow and consume 5 v/v of ethanol in 48 hr in the presence of initial acetic acid concentration (0.5%) at 30° C. In conclusion, the mentioned methods for preservation and reactivation of freeze-dried Acetobacter senegalensis can provide a promising tool for decreasing the lag phase of vinegar fermentation. [less ▲]

Lutte biologique contre le doryphore à l'aide de la chrysope

Poster (2011, October 27)

Le doryphore est le plus important défoliateur de pommes de terre. Lors de ces dernières années, une réapparition, certainement liée à l’augmentation des températures sous nos latitudes, a été constatée ... [more ▼]

Le doryphore est le plus important défoliateur de pommes de terre. Lors de ces dernières années, une réapparition, certainement liée à l’augmentation des températures sous nos latitudes, a été constatée. Face aux futures restrictions européennes en matière d’insecticides ainsi qu’aux exigences du consommateur, des techniques de lutte plus « vertes » sont à développer. Lors de nos tests en laboratoire, l’utilisation de la larve de la chrysope a permis une réduction efficace des œufs et larves de doryphores. Cela permet donc d’entrevoir une lutte entomophage contre le doryphore via l’utilisation d’un prédateur naturel propre à nos régions. [less ▲]

Preparation and characterization of thermo-responsive gold nanohybrids

Poster (2011, October 25)

Stimuli-responsive nano-materials have been playing increasingly important roles in the biomedical field due to their ability to alter the physico-chemical properties in response to external stimuli, such ... [more ▼]

Stimuli-responsive nano-materials have been playing increasingly important roles in the biomedical field due to their ability to alter the physico-chemical properties in response to external stimuli, such as temperature, pH, ionic strength, magnetic field, etc. Nanohybrids bearing an inorganic core and thermo-responsive polymer shell are particularly applicable in target delivery and controlled drug release. Poly (N-vinylcaprolactam) (PNVCL) and its copolymers, exhibiting lower critical solution temperature (LCST) where the transition between hydrophilic and hydrophobic state happens, is one of the optimal choices for this core/shell structure. Here we present the in-situ fabrication of thermo-responsive gold nanohybrids coated with a novel poly(vinyl alcohol)-b-poly(N-vinylcaprolactam) (PVOH-b-PNVCL) block copolymer prepared by the cobalt-mediated radical polymerization (CMRP). The interaction between both PVOH and PNVCL segments and gold nanoparticles was confirmed by FT-IR spectra. A sharp thermo-induced phase transition with a good reversibility upon change in temperature was detected by DLS and UV/vis spectrometer. Furthermore, the presence of hydrophilic PVOH moieties endows the gold nanohybrids with improved colloidal stability above LCST without any flocculation detected, compared with the gold nanoparticles stabilized with PNVCL homopolymer. This kind of gold nanohybrids can be envisaged as a new drug delivery vehicle. [less ▲]

Characterization of the interaction between nanoformulated drugs and model lipid membranes towards improved drug delivery systems

Poster (2011, October 25)

The importance of distinguishing item and order memory for understanding short-term memory deficits in brain-damaged patients

Poster (2011, October 18)

Selective verbal short-term memory (STM) deficits are rare and are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore here the distinction ... [more ▼]

Selective verbal short-term memory (STM) deficits are rare and are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore here the distinction between STM for item information (the items and their phonological and semantic characteristics) and STM for order information (the order of items within a list) to separate STM and language impairment. Recent models of STM consider that STM for item information depends upon activation of the language system, and hence item STM deficits should be associated with language impairment. By contrast, STM for order information is considered to recruit a specific system, distinct from the language system. Hence, order STM should be impaired in patients with language-independent STM deficits. We applied this rationale to the exploration of STM profiles of two patients with a history of aphasia, MB and CG. At the time of this study, patient MB showed poor digit and word STM spans associated with a mild impairment at the level of phonological input processing. Patient CG showed poor STM spans with no residual language impairment. A first experiment assessed STM for order and item information, using order and item probe recognition tasks. Patient MB showed severely impaired performance in the item condition (Z=-4.71; p<.001) but a milder deficit in the order condition (Z=-2.17; p<.05). CG on the other hand showed perfectly preserved performance for the item condition (Z=-0.43) but significantly slowed response times for the order condition (Z=-2.20; p<.05). In a second experiment determining item and order error proportions in an immediate serial recall task for six-word lists, MB showed a significantly increased proportion of item errors (Z=-3.24 and -2.6 for positions 5 and 6, respectively; p<.05) but not of order errors (Z=-1.47), while CG showed perfectly preserved item recall (Z=0.22) but an increase of order errors especially in final list positions (Z =-2.57 for position 6; p<.05). A third experiment assessed reconstruction of serial order for digit lists showing perfectly preserved performance in patient MB (Z=1.32) but severely impaired performance in patient CG (Z=-3.49; p<.05). A final experiment assessed new word learning performance, given that STM for order has been shown to be a critical determinant of vocabulary acquisition in children and adults. CG showed impaired new word learning performance in a paired associate word-new word learning experiment (Z=-3.29; p<.05) but not in a word-word learning control experiment (Z=0.13), while MB showed a more general verbal learning impairment (word-nonword: Z=-3.09, p<.05; word-word: Z=-4.8, p<.05). This study provides the first demonstration of a dissociation between STM for order and STM for item information in patients with a history of aphasia, and further shows that patients with residual language impairment are more likely to present impaired STM for item information which is considered to depend on the integrity of the language system. Order STM deficits on the other hand may represent what is commonly referred to as selective STM impairment, highlighting the importance of distinguishing between item and order STM processes when exploring STM deficits in aphasic patients. [less ▲]

Comparison between the new AccuChek Inform II glucose meter and the Rapidlab 865 blood gas analyzer: implications for use of the Inform II in tight glycemic control

Poster (2011, October 15)

Les volatils racinaires de l’orge: un langage souterrain entre plantes?

Poster (2011, October 13)

Les larves de taupins sont attirées par différentes sources de volatils racinaires

Poster (2011, October 13)

Grâce à des tests olfactométriques, nous voulons mettre en évidence la capacité de certains COVs d’origine racinaire à attirer ou repousser les larves de taupins. Nous montrons ici les premiers résultats ... [more ▼]

Grâce à des tests olfactométriques, nous voulons mettre en évidence la capacité de certains COVs d’origine racinaire à attirer ou repousser les larves de taupins. Nous montrons ici les premiers résultats obtenus grâce à des olfactomètres tubulaires, soit l’attraction par des COVs issus de racines hachées et l’attraction par le 2-pentylfuran, volatil contenu dans les racines d’orge. [less ▲]

Le taupin : un ravageur souterrain préoccupant

Poster (2011, October 13)

Les larves de taupin représentent une menace pour un grand nombre de cultures céréalières et légumières. Elles s’attaquent aux racines, aux radicelles, aux tubercules, aux graines en germination et ... [more ▼]

Les larves de taupin représentent une menace pour un grand nombre de cultures céréalières et légumières. Elles s’attaquent aux racines, aux radicelles, aux tubercules, aux graines en germination et peuvent percer de part en part le collet, entraînant ainsi de graves lésions voire la mort des plants attaqués. Nous présentons ici ces insectes, les techniques de lutte actuellement envisageables, ainsi que notre approche de l’étude de ces insectes dans le but de mieux envisager la lutte intégrée à leur encontre. [less ▲]

A method inspired by nature for the production of original and purified prebiotic preparations containing isomaltooligosaccharides and gluconic acid and fortified in calcium and magnesium

Poster (2011, October 05)

Hydro and hydro-mechanical modelling of ventilation test in clayey rocks

Poster (2011, October 03)

Long-term repository of radioactive waste in deep argillaceous geological media needs a good understanding of the host formation behaviour. Considering the safety function of the formation and the need of ... [more ▼]

Long-term repository of radioactive waste in deep argillaceous geological media needs a good understanding of the host formation behaviour. Considering the safety function of the formation and the need of low permeability, the behaviour of the excavation damaged zone (EDZ) is a major issue. Because drainage may modify the structure and the size of this zone, a ventilation test (SDZ) is realised by the French national radioactive waste management agency (ANDRA) in an experimental gallery of the Meuse/Haute-Marne underground research laboratory located in Callovo-Oxfordian claystone. The aim is to characterise the effect of the desaturation and possible resaturation of the damaged zone due to controlled ventilation. Numerical modellings are performed to reproduce the ventilation test. A biphasic flow model in unsaturated soil and an elasto-plastic constitutive law are used for the host formation. A nonclassical boundary condition has been developed in order to model the exchanges between the cavity and the rock. Numerical results show that it is possible to calibrate the models to obtain a satisfactory reproduction of the in situ experimental measurements and a better understanding of the fluid transfer around the gallery during the ventilation test. [less ▲]

Rhizobacterial volatile organic compounds modulate biomass production and root architecture in Arabidopsis thaliana (L.) Heynh. and Brachypodium distachyon (L.) P. Beauv.

Poster (2011, October)

Données épidémiologiques sur la santé bucco-dentaire chez des enfants scolarisés en région liégeoise

Poster (2011, October)

La prévalence carieuse chez les enfants fait l’objet de nombreuses publications émanant de l’OMS. Ainsi, nous disposons de nombreuses données épidémiologiques issues de divers pays et concernant la santé ... [more ▼]

La prévalence carieuse chez les enfants fait l’objet de nombreuses publications émanant de l’OMS. Ainsi, nous disposons de nombreuses données épidémiologiques issues de divers pays et concernant la santé bucco-dentaire des enfants. Néanmoins, force est de constater que peu d’études ont été réalisées en Belgique et de par ce fait, les données concernant la maladie carieuse et les besoins de traitement chez les enfants Belges restent très limitées. Une étude pilote a été menée par l’équipe du Service de dentisterie conservatrice de l’université de Liège afin de tenter de pallier à ce manquement. L’objectif de cette enquête clinique était de répertorier les facteurs de risques de la maladie carieuse et de recenser les épisodes carieux (présents et passés) chez des enfants âgés entre 6 et 13 ans. Un dépistage clinique a été mené dans 2 écoles de la région liégeoise et a intéressé 306 enfants. D’une part, nos résultats ont montré que la sévérité de l’indice CAO/D et de l’indice cao/d répondaient parfaitement aux objectifs fixés par l’OMS en 1981 (CAO/D < 3) mais qu’ils étaient loin de rencontrer ceux fixés pour 2020 (CAO/D < 1,5). D’autre part, il ressort de notre enquête que peu de jeunes patients sont indemnes de caries (16 %). En effet 84 % des patients examinés avaient déjà présenté un ou plusieurs épisodes carieux. Toutefois, nos résultats tendent à montrer que la maladie carieuse est significativement plus fréquente en denture de lait qu’en denture définitive (p < 0,001). En conclusion, notre étude pilote n’apporte aucun élément neuf dans la connaissance du processus carieux et de son dépistage mais elle a au moins le mérite de planter les premiers jalons qui conduiront à une meilleure connaissance de l’état de santé bucco-dentaire chez des enfants scolarisés en région liégeoise. [less ▲]

CO2 exchange above a cultivated savanna in sudanian region in northern part of Benin (West Africa)

Poster (2011, October)

Characterization of the interaction between nanoformulated drugs and model lipid membranes towards improved drug delivery systems

Poster (2011, October)

Tight Glycemic Control in Critically Ill Patients: the STAR Framework

Poster (2011, October)

Investigation of mevalonate pathway in aphids

Poster (2011, October)

Silicone-based drug reservoirs manufacturing process - Critical quality attributes evaluation using NIR and Raman spectroscopy

Poster (2011, October)

Structural Optimization: LBR-5 Software and its application

Poster (2011, October)

As well known already in earliest phases of a ship project many aspects and choices depend on the structural design which has been defined only at a preliminary level. This trend appears to be similar for ... [more ▼]

As well known already in earliest phases of a ship project many aspects and choices depend on the structural design which has been defined only at a preliminary level. This trend appears to be similar for merchant ships, passenger ships and motor yachts. Only in the final part of the project some shipyards begin to apply optimization processes, more or less sophisticated, in order to refine the structural design in view of reducing the weight and/or the construction cost. The weight in particular has a very important impact on pleasure vessels, both motor and sailing. Structural modifications suggested by such optimization procedures imply a number of second order changes in related items such as plant, outfitting and others. As a consequence the structural optimization could be particularly useful if it can be applied during the first stages of the project, this way avoiding very expensive time losses and changes caused by any structural modifications. The LBR-5 software has been successfully used to optimize hull structures of a 60 meters mega yacht. Differently from large ships, the mega yacht has not a “cylindrical body” in the central part of the hull. So, a new module of the software has been used in order to analyze several sections of the ship and to perform an overall optimization. For this application the optimization analysis has been carried out by different approaches: assuming the weight as the objective function a gain of about 8% has been achieved, while a least cost optimization allowed a reduction of 15%. [less ▲]

In vitro ESR measurements: powerful tool to study toxic effects on cells

Poster (2011, October)

Electron spin resonance spectroscopy (ESR) is a highly efficient technique able to access a wide range of information about the unfavourable effects caused by a chemical or a drug. ESR in spin labelling ... [more ▼]

Electron spin resonance spectroscopy (ESR) is a highly efficient technique able to access a wide range of information about the unfavourable effects caused by a chemical or a drug. ESR in spin labelling fits well in with the study of membranes and particularly with the changes in lipid bilayer organisation induced by drug. Our team previously developed a way to quantify the effective lipid bilayer microviscosity of cell membranes and consequently put in evidence the fluidity effect of the propofol. Recently, the importance of lipid raft domains has been shown due to their important role as a platform for signal transduction and protein sorting. We propose to highlight the effect of the Randomly methylated beta cyclodextrin (Rameb) on these domains on membrane model (liposomes) as well as on colon carcinoma cell line (HCT-116). Futhermore, ESR in spin trapping is used in order to identify and quantify the generation of Reactive Oxygen Species (ROS) in cells. An ESR study on human colon carcinoma cell line has highlighted the cytotoxicity of the photosensitizer pyrophephorbide-a methyl ester. Using an intracellular located spin trap (4-pyridyl 1-oxide-N-tert-butylnitrone, POBN), it has been shown that the photoexcitation of the dye is able to generate superoxide anions, hydroxyl radicals and singlet oxygen. Moreover, ESR is one of the most sensitive method for measuring cellular oxygen consumption. Our team has studied the alterations of oxygen respiratory in human tubular renal cells treated with an endotoxin (lipopolysaccharide, LPS). The incubation of HK-2 cells with LPS elicited a decreased in oxygen consumption suggesting a down-regulation of the cells metabolism. [less ▲]

In-line active content determination of polymeric implant by near infrared spectroscopy

Poster (2011, October)

L'entrepreneuriat féminin au Maroc: Quelles sont les variables contextuelles qui influencent l'entrepreneuriat?

Poster (2011, September 30)

L’objectif principal de cet article est d’explorer les fondements de l’entrepreneuriat féminin au Maroc et de présenter les modèles existants. Ce qui nous amène à poser les questions suivantes : « Quels ... [more ▼]

L’objectif principal de cet article est d’explorer les fondements de l’entrepreneuriat féminin au Maroc et de présenter les modèles existants. Ce qui nous amène à poser les questions suivantes : « Quels sont les variables contextuelles et socio-économiques qui influencent l’entreprenariat au Maroc ? » et « qui sont ses femmes qui ont choisi d’entreprendre au féminin, en bravant courageusement les différents obstacles socio-culturelles qui caractérisent la société marocaine? ». Présenté ainsi, notre recherche entend dresser un état de l’art des différentes variables pouvant expliquer les composantes de l’entrepreneuriat féminin au Maroc et de conceptualiser ses mécanismes opérationnels afin de proposer des pistes de réflexions adaptées au contexte marocain et applicables par les femmes entrepreneures. [less ▲]

nanostructured carbon materials by surfactant-templating of resorcinol-formaldehyde gels: towards a control of porosity for energy storage applications

Poster (2011, September 26)

Biocontrol proteomics:Implication of the pentoses phosphates pathway in the antagonist effect of Pichia anomala against Botrytis cinerea on apple

Poster (2011, September 21)

The growing interest of the consumers for the wholesome food and the protection of the environment as well as the development of resistant pathogens to pesticides, stimulate the interest of growers to ... [more ▼]

The growing interest of the consumers for the wholesome food and the protection of the environment as well as the development of resistant pathogens to pesticides, stimulate the interest of growers to apply biological control methods. Pichia anomala strain K was previously identified as an efficient biocontrol agent of the main apple pathogens, Botrytis cinerea and Penicillum expansum. Further study demonstrated the complexicity of the mode of action of P. anomala against B. cinerea. A cDNA-AFLP and gene disruption study revealed implication of exo-β-1,3-glucanases in the mode of action of P. anomala strain Kh6 (a haploid form of P. anomala strain K displaying the same biocontrol properties). However, these studies suggested also implication of other factors. The present study aims to increase our knowledge of the mode of action of P. anomala strain Kh6 against B. cinerea using an in situ approach allowing the triple interaction, host/pathogen/antagonist and the proteomic tool allowing to study the ultime expression of the genome without a priori. One 50mm wound per apple were covered by a membrane and inoculated by a P. anomala suspension then by B. cinerea or not. Samples were collected during the exponential and stationary phase to identify the early and later responses to the presence of B. cinerea. After extraction, proteins were separated on 2-D gels. Spots influenced by the presence of B. cinerea in exponential and stationary phases were identified by MALDI-ToF. One hundred five and sixty spots of proteins were influenced by the presence of B. cinerea in exponential and stationary phases respectively. In exponential phase, P. anomala Kh6 in absence of B. cinerea uses mainly the glycolysis pathway, whereas in presence of pathogen, it orientates its energetic metabolism to the oxidative phosphorylation and sets up the pentose phosphate pathway. Thanks to this new orientation, P. anomala Kh6 probably obtains energy and nucleic acids allowing to colonize the wound as fast as in absence of B. cinerea and prevents the use of nutrients by the pathogen. In stationary phase, no differences in the P. anomala Kh6 energetic metabolism, in absence and in presence of B. cinerea were observed. During that phase, P. anomala Kh6 seems to use the alcoholic fermentation in order to face the nutrients impoverishment of the substrate. [less ▲]

A robustness study to investigate the performance of parametric and non-parametric tests used in Model-Based Multifactor Dimensionality Reduction Epistasis Detection.

Poster (2011, September 19)

Model-Based Multifactor Dimensionality Reduction (MB-MDR) is data mining technique to identify gene-gene interactions among 1000nds of SNPs in a fast way, without making assumptions about the mode of ... [more ▼]

Model-Based Multifactor Dimensionality Reduction (MB-MDR) is data mining technique to identify gene-gene interactions among 1000nds of SNPs in a fast way, without making assumptions about the mode of genetic interactions. By construction, one of the implementations of MB-MDR involves testing one multi-locus genotype cell versus the remaining cells, hereby creating two imbalanced groups for trait distribution comparison. To date, for continuous traits, we have adopted a standard F-test to compare these groups. When normality assumption or homoscedasticity no longer hold, highly inflated results are to be expected. The power and type I error control of MB-MDR under these assumptions has been thoroughly investigated in Mahachie John et al [1]. The aim of this study is to assess, through simulations, the effects of ANOVA model violations on the performance of Model-Based Multifactor Dimensionality Reduction (MB-MDR). We quantify their effect on MB-MDR using default options, but at the same time introduce alternative options with increased performance. The better handling of imbalanced data using robust approaches [2] within a MB-MDR context is exemplified on real data for asthma-related phenotypes. 1. EJHG (2011), Early view 2. David Freedman, Statistical Models: Theory and Practice, Cambridge University Press (2000), ISBN 978-0521671057 [less ▲]

Comparison Of Different Methods For Detecting Gene-Gene Interactions In Case-Control Data

Poster (2011, September 19)

It is generally believed that epistasis makes an important contribution to the genetic architecture of complex disease, and numerous statistical and bioinformatics methods have been developed to detect it ... [more ▼]

It is generally believed that epistasis makes an important contribution to the genetic architecture of complex disease, and numerous statistical and bioinformatics methods have been developed to detect it. We compare several state-of-the-art epistasis detection methods in terms of empirical power, type-I error control, and CPU time. The methods compared include Model-Based Multifactor Dimensionality Reduction (MB-MDR) [1, 2], BOolean Operation-based Screening and Testing (BOOST) [3], EPIBLASTER [4], Random Jungle (RJ) [5], Logistic Regression and PLINK. Our comparative study is based on an extensive simulation study using different two-locus models, exhibiting both main effects and epistasis [3]. In these simulations, 100 SNPs are generated, no LD between them. All genotypes are assumed to be in Hardy-Weinberg equilibrium. Furthermore, 2 disease-associated SNPs are selected, with MAFs set to 0.1, 0.2 and 0.4. The MAFs of the non-disease associated SNPs are uniformly distributed on [0.05, 0.5]. In order to achieve high accuracy in empirical power estimation, all simulation settings involve 1000 replicates. All methods are applied to WTCCC Crohn's Disease data. [1] Calle, M.L. et al. (2008), Tech. Rep. No. 24, Dep. of Systems Biology, Univ. de Vic [2] Cattaert, T. et al. (2011), Ann. Hum. Gen. 75, 78-89 [3] Wan, X. et al. (2010), Am. J. Hum. Gen. 87, 325-340 [4] Kam-Thong, T. et al. (2011), Eur. J. Hum. Gen. 19, 465-471 [5] Schwartz, D.F. et al. (2010), Bioinf. 26, 1752-1758 [less ▲]

Insertional mutagenesis to select mutants for modified hydrogen photoproduction in Chlamydomonas reinhardtii

Poster (2011, September 18)

The unicellular green alga Chlamydomonas reinhardtii has evolved the ability to redirect electrons from the photosynthetic chain to drive hydrogen production via chloroplast oxygen-sensitive hydrogenases ... [more ▼]

The unicellular green alga Chlamydomonas reinhardtii has evolved the ability to redirect electrons from the photosynthetic chain to drive hydrogen production via chloroplast oxygen-sensitive hydrogenases. This process occurs under anaerobic conditions and provides a biological basis for solar-driven hydrogen production. Nevertheless, the yield is a major limitation for an economic viability and fundamental knowledge is still needed in order to have a better understanding of the process. In 2000, Melis and co-worker defined a protocol allowing a sustainable hydrogen production in sulfur deprivation condition. By adjustment of an existent protocol called the Winkler test, we are trying to isolate mutants with an attenuated photosynthesis to respiration capacity ratio (P/R ratio). This kind of mutants could be able to reach anoxia needed for hydrogenases activity without the stressful impact of sulfur deprivation. An insertional mutagenesis of Chlamydomonas has been carried out with an hygromycin resistance cassette and about 2500 transformants have generated and screened by the adapted Winkler test. We have isolated several oxygen-consuming mutants and the most promising one is subject to functional, molecular and genetic characterization. [less ▲]

Establishment of Parathyroid hormone reference range on 10 different assay kits: impact of the recruitment of the population

Poster (2011, September 18)

Automated Measurement of Total 25OH Vitamin D in the IDS iSYS System

Poster (2011, September 17)

Nanostructured carbon materials by surfactant-templating of resorcinol-formaldehyde gels: towards a control of porosity

Poster (2011, September 12)

DOES INCREASING LEVEL OF CONDENSED DISTILLERS SOLUBLES (PROTIWANZE®) SUPPLEMENTATION AFFECT MILK PRODUCTION IN DAIRY CATTLE ?

Poster (2011, September 08)

INTRODUCTION The objective of this study was to evaluate whether introducing the condensed distillers solubles Protiwanze® (PW) at different concentrations in dairy cows diet induces changes in milk ... [more ▼]

INTRODUCTION The objective of this study was to evaluate whether introducing the condensed distillers solubles Protiwanze® (PW) at different concentrations in dairy cows diet induces changes in milk production. MATERIAL AND METHODS Three herds (72 Holstein and 25 Brown Swiss, DIM = 101 ± 57; daily milk production = 34.90 ± 8.40 L) received successively two RTM differing in PW content for 4 weeks, including a 7-day transition: 0% and 10% on a dry matter basis for Herd 1 and 10% and 15% for Herd 2 and 3. Both concentrations were distributed alternatively and repeated twice, each cow being its own control. Rations were formulated to meet energy and nitrogen requirements. During each testing period, animals were scored (Body Condition, Rumen Fill, Fecal Consistency, Undigested Fraction according to Zaaier (2001)) and their milk production and composition were measured by the Dairy Herd Improvement. RESULTS AND CONCLUSION Increasing the level of PW did not significantly change milk production in any Herd: Values were for Herd 1 at PW0%: 33.08 ± 0.76 L, at 10%: 31.66 ± 0.68 L, for Herd 2 at PW10%: 32.85 ± 0.93 L and at 15%: 32.37 ± 0.89, for Herd 3 at PW10%: 28.71 ± 1.21 L and at 15%: 31.80 ± 1.16. In Herd 1, milk urea decreased from 243.80 ± 4.55 mg/L for PW0% to 218.05 ± 4.03 mg/L for PW10%, (p<0.01), while fat percentage increased from 3.38% ± 0.09 (PW0%) to 3.77% ± 0.08 (PW10%) (p<0.01). Concerning scores, unconclusive changes were observed. Although increasing level of PW in dairy cows diet did not change milk production or composition, it is profitable since PW is 30-40% cheaper than other protein supplements like soya and canola meals. Moreover, it allowed to lower milk cost price by 1,5 eurocent per liter, when used at higher concentration. [less ▲]