Morphological and Molecular Characterization of Orchid Fruit Development

Efficient seed dispersal in flowering plants is enabled by the development of fruits, which can be either dehiscent or indehiscent. Dehiscent fruits open at maturity to shatter the seeds, while indehiscent fruits do not open and the seeds are dispersed in various ways. The diversity in fruit morphology and seed shattering mechanisms is enormous within the flowering plants. How these different fruit types develop and which molecular networks are driving fruit diversification is still largely unknown, despite progress in eudicot model species. The orchid family, known for its astonishing floral diversity, displays a huge variation in fruit dehiscence types, which have been poorly investigated. We undertook a combined approach to understand fruit morphology and dehiscence in different orchid species to get more insight into the molecular network that underlies orchid fruit development. We describe fruit development in detail for the epiphytic orchid species Erycina pusilla and compare it to two terrestrial orchid species: Cynorkis fastigiata and Epipactis helleborine. Our anatomical analysis provides further evidence for the split carpel model, which explains the presence of three fertile and three sterile valves in most orchid species. Interesting differences were observed in the lignification patterns of the dehiscence zones. While C. fastigiata and E. helleborine develop a lignified layer at the valve boundaries, E. pusilla fruits did not lignify at these boundaries, but formed a cuticle-like layer instead. We characterized orthologs of fruit-associated MADS-domain transcription factors and of the Arabidopsis dehiscence-related genes INDEHISCENT (IND)/HECATE 3 (HEC3), REPLUMLESS (RPL) and SPATULA (SPT)/ALCATRAZ (ALC) in E. pusilla, and found that the key players of the eudicot fruit regulatory network appear well-conserved in monocots. Protein-protein interaction studies revealed that MADS-domain complexes comprised of FRUITFULL (FUL), SEPALLATA (SEP) and AGAMOUS (AG) /SHATTERPROOF (SHP) orthologs can also be formed in E. pusilla, and that the expression of HEC3, RPL, and SPT can be associated with dehiscence zone development similar to Arabidopsis. Our expression analysis also indicates differences, however, which may underlie fruit divergence

Well being of obstetric patients on minimal blood transfusions (WOMB trial)

Background: Primary postpartum haemorrhage is an obstetrical emergency often causing acute anaemia that may require immediate red blood cell (RBC) transfusion. This anaemia results in symptoms such as fatigue, whic

Randomised controlled trial of a psychiatric consultation model for treatment of common mental disorder in the occupational health setting

BACKGROUND: Common mental disorders are the most prevalent of all mental disorders, with the highest burden in terms of work absenteeism and utilization of health care services. Evidence-based treatments are available, but recognition and treatment could be improved, especially in the occupational health setting. The situation in this setting has recently changed in the Netherlands because of new legislation, which has resulted in reduced sickness absence. Severe mental disorder has now become one of the main causes of work absenteeism. Occupational physicians (OPs) are expected to take an active role in diagnosis and treatment, and seem to be in need of support for a new approach to handle cases of more complex mental disorders. Psychiatric consultation can be a collaborative care model to achieve this. METHODS/DESIGN: This is a two-armed cluster-randomized clinical trial, with randomization among OPs. Forty OPs in two big companies providing medical care for multiple companies will be randomized to either the intervention group, i.e. psychiatric consultation embedded in a training programme, or the control group, i.e. only training aimed at recognition and providing Care As Usual. 60 patients will be included who have been absent from work for 6–52 weeks and who, after screening and a MINI interview, are diagnosed with depressive disorder, anxiety disorder or somatoform disorder based on DSM-IV criteria. Baseline measurements and follow up measurements (at 3 months and 6 months) will be assessed with questionnaires and an interview. The primary outcome measure is level of general functioning according to the SF-20. Secondary measures are severity of the mental disorder according to the PHQ and the SCL-90, quality of life (EQ-D5), measures of Return To Work and cost-effectiveness of the treatment assessed with the TiC-P. Process measures will be adherence to the treatment plan and assessment of the treatment provided by the Psychiatric Consultant (PC) in both groups. DISCUSSION: In the current study, a psychiatric consultation model that has already proved to be effective in the primary care setting, and aimed to enhance evidence-based care for patients with work absenteeism and common mental disorder will be evaluated for its efficacy and cost-effectiveness in the occupational health setting

Mains driven transmitter & portable receiver for visible light communication Indoor positioning

Les possibilités de la communication par la lumière visible (Visible Light Communication, VLC) ont été étudiées pour le calcul de position à l’intérieur d’une pièce. La fixation de plusieurs lampes à LEDs au plafond peut avoir deux buts: premièrement, l’éclairage dans une chambre et deuxièmement la transmission de séquences binaires. Les séquences binaires sont envoyées à une haute fréquence et sont donc invisibles pour les yeux humains. Un appareil optique peut détecter les séquences et mesurer leurs amplitudes. Les amplitudes différentes sont une fonction des distances. Cette propriété permet de calculer la position du récepteur dans la pièce. Pour l’émetteur, un prototype autonome a été développé. Il est alimenté par le secteur. Un transformateur est utilisé pour piloter la LED. Deux possibilités différentes pour implémenter la sequence binaire sur la lumière envoyée ont été examinées: la première consiste à utiliser l’interrupteur du circuit à transformateur ”flyback” et l’autre à plaçer un interrupteur en série avec le LED. Un circuit programmable FPGA est utilisé pour générer la séquence binaire. Pour ce qui est du récepteur, une photodiode est utilisée avec un circuit analogique pour détecter, filtrer et amplifier la sequence binaire envoyée. Un convertisseur A/D est utilisé pour numériser l’information reçue. Il est alors possible d’envoyer ces données à un appareil numérique où un programme peut servir `a traiter ces données.The possibilities of Visible Light Communication (VLC) for indoor positioning are being studied in this work. The placement of several LEDs on the ceiling can have a dual purpose: first, the lighting in the room and second the transmission of binary sequences. The binary sequences are send at a high frequency and are thus invisible for the human eye. A light receiving device can detect these sequences and measure their amplitude. The different amplitudes are in function of the distances. This property allows to calculate the position of the receiver in the room. For the sending part, a stand-alone prototype is created to be connected to the mains in a room. A transformer circuit (Flyback) is used to drive the led. Two different possibilities to implement the binary sequence in the emitted light are investigated. Once by using the switch of the transformer circuit and once by placing a switch in series with the LED. An FPGA is used to generate the binary sequence. For the receiving part, a photodiode is used with an analog circuitry to detect, filter and amplify the transmitted light sequences. An ADC is used to digitalize the received information. This makes it possible to send the data to a digital device. Software can then be used to process the data

Effect of alternating influent carbon source composition on activated sludge bioflocculation

The impact of alternating influent carbon sources, i.e., glucose and starch, on activated sludge bioflocculation was investigated. To this end, four lab-scale reactors were operated during a long-term experiment. During this period the influent carbon source ratio (glucose/starch) was alternated every 7 or 35 days (i.e., a fast and slow switching frequency). Bioflocculation was monitored throughout the entire experiment using an extensive set of parameters, including macroscopic and microscopic activated sludge characteristics. Sludge hydrophobicity remained high (>80%) throughout the experiment indicating good bioflocculation. However, sludge settleability decreased for all four reactors after a 60 day adaptation period to the applied alternation in influent carbon source. During this adaptation period, floc size decreased due to the release of microcolonies. The subsequent period was characterized by a decrease in settleability, coinciding with a release of primary particles and an increase in floc size. The observed phenomena could be linked with the protein concentration near the floc surface. This fraction mainly consists of hydrolytic enzymes necessary for the degradation of starch and is responsible for a progressive deterioration of the EPS matrix. The results of this specific study indicate to be independent of the influent carbon source ratio or switching frequency.publisher: Elsevier articletitle: The effect of alternating influent carbon source composition on activated sludge bioflocculation journaltitle: Journal of Biotechnology articlelink: http://dx.doi.org/10.1016/j.jbiotec.2013.07.012 content_type: article copyright: Copyright © 2013 Elsevier B.V. All rights reserved.status: publishe

Microscopic image analysis versus sludge volume index to monitor activated sludge bioflocculation - a case study

The influent ratio of Mono- over Polyvalent cations (M/P ratio) influences activated sludge bioflocculation. A more thorough insight through means of conventional macroscopic parameters, Sludge Volume Index (SVI), and Effluent Suspended Solids (ESS), and microscopic image analysis was pursued in this work. Therefore, a long term experiment was conducted during which activated sludge was exposed twice to a transition in influent M/P ratio from 1.5 to 15. Two distinct observations were made. The first transition indicates the existence of a loosely attached layer evidenced by the temporary release of small sludge particles as observed by image analysis. This release was followed by a decrease in the amount of small sludge particles and increase in floc size indicating good bioflocculated sludge. The second transition results in a massive release of small particles leading to complete sludge deflocculation. (De)flocculation was monitored by both SVI and microscopic image analysis, whereas during the first transition the change in bioflocculation condition could only cleary be monitored by means of microscopic image analysis. Based on this study, microscopic image analysis proves to be a powerful monitoring tool to assess the bioflocculation condition of the activated sludge, whereas SVI is unable to accurately monitor its bioflocculation condition. © 2013 Copyright Taylor and Francis Group, LLC.status: publishe

Self-assembled ligand-capped plasmonic Au nanoparticle films in the Kretschmann configuration for sensing of volatile organic compounds

International audienc

Thermocaproicibacter melissae gen. nov., sp. nov., a thermophilic chain-elongating bacterium, producing n-caproate from polymeric carbohydrates

Strain MDTJ8 T is a chain-elongating thermophilic bacterium isolated from a thermophilic acidogenic anaerobic digestor treating human waste while producing the high commodity chemical n -caproate. The strain grows and produces formate, acetate, n -butyrate, n -caproate and lactate from mono-, di- and polymeric saccharides at 37–60 °C (optimum, 50–55 °C) and at pH 5.0–7.0 (optimum, pH 6.5). The organism is an obligate anaerobe, is motile and its cells form rods (0.3–0.5×1.0–3.0 µm) that stain Gram-positive and occur primarily as chains. Phylogenetic analysis of both the 16S rRNA gene and full genome sequence shows that strain MDTJ8 T belongs to a group that consists of mesophylic chain-elongating bacteria within the family Oscillospiraceae , being nearest to Caproicibacter fermentans EA1 T (94.8 %) and Caproiciproducens galactitolivorans BS-1 T (93.7 %). Its genome (1.96 Mbp) with a G+C content of 49.6 mol% is remarkably smaller than those of other chain-elongating bacteria of the family Oscillospiraceae . Pairwise average nucleotide identity and DNA–DNA hybridization values between strain MDJT8 T and its mesophilic family members are less than 70 and 35 %, respectively, while pairwise average amino acid identity values are less than 68 %. In addition, strain MDJT8 T uses far less carbohydrate and non-carbohydrate substrates compared to its nearest family members. The predominant cellular fatty acids of strain MDTJ8 T are C 14 : 0 , C 14 : 0 DMA (dimethyl acetal) and C 16 : 0 , while its polar lipid profile shows three unidentified glycophospholipids, 11 glycolipids, 13 phospholipids and six unidentified lipids. No respiratory quinones and polyamines are detected. Based on its phylogenetic, genotypic, morphological, physiological, biochemical and chemotaxonomic characteristics, strain MDTJ8 T represents a novel species and novel genus of the family Oscillospiraceae and Thermocaproicibacter melissae gen. nov., sp. nov. is proposed as its name. The type strain is MDTJ8 T (=DSM 114174 T =LMG 32615 T =NCCB 100883 T )

The impact of deflocculation-reflocculation on fouling in membrane bioreactors

Membrane bioreactors (MBRs) have proven to be a valuable alternative for conventional activated sludge plants. Membrane fouling remains, however, a significant drawback. Stable operation of a membrane bioreactor requires a good sludge condition. In this paper it is evidenced that bioflocculation is a crucial factor within that context. By changing the ratio of monovalent over polyvalent cations ([M/P]) in the influent, a deflocculation-reflocculation event was induced during which the impact of bioflocculation on fouling in membrane bioreactors could be studied. In a first phase, a high [M/P] influent was fed to the MBR which resulted in severe sludge deflocculation and worsened filtration characteristics. A low [M/P] influent was subsequently fed to the MBR. Within 3 weeks, the activated sludge reflocculated and filtration characteristics improved significantly. Monitoring of bioflocculation in MBRs is thus of extreme importance to start possible remediation as quickly as possible. Fragment surface proved to be a valuable parameter in that respect. In contrast, no clear relation between EPS and filtration characteristics could be found. This work substantiates the hypothesis that a well functioning dynamic secondary membrane, built up by robust activated sludge flocs, can prevent severe (irreversible) fouling in MBRs. © 2009 Elsevier B.V. All rights reserved.status: publishe