Relationships between seasonal changes in diet of multimammate rat (Mastomys natalensis) and its breeding patterns in semi-arid areas in Tanzania

The diet and breeding patterns of Mastomys natalensis in semi-arid areas of Isimani division, Iringa region, Tanzania were investigated in maize fields and fallow land. The aim was to investigate the influence of diet on breeding patterns of M. natalensis. Removal trapping was used to capture rodents and analyse diet categories while Capture-mark-release trapping was used to investigate breeding patterns of female M. natalensis. Mastomys natalensis comprised 94%of the total capture, and the remaining 6% comprised of six other species. Statistical analysis of food preferences indicated that both vegetative materials and seeds were significantly higher in the overall diet of M. natalensis compared with other food materials. Significant differences in the proportions of vegetativematerials and seeds were found between seasons (dry, wet), but not between habitats (fallow, maize). There was a clear seasonal pattern in the proportion of reproductively active females with peaks in April and troughs in October. The proportion of vegetative materialswas highest during thewet season and correlated positively with reproductive activity, suggesting that vegetative materials contain certain compounds (e.g. 6-MBOA) that trigger reproductive activity in M. natalensis. The breeding activity of M. natalensis in semi-arid areas might, thus, be reduced by limiting access to fresh vegetative food (e.g. young sprouting grass)

Study protocol for a randomized controlled trial : prophylactic swallowing exercises in head-and-neck cancer patients treated with (chemo)radiotherapy (PRESTO trial)

Background: Dysphagia is a common and serious complication after (chemo)radiotherapy (CRT) for head-and-neck cancer (HNC) patients. Prophylactic swallowing exercises (PSE) can have a significantly positive effect on post-treatment swallowing function. However, low adherence rates are a key issue in undermining this positive effect. This current randomized trial will investigate the effect of adherence-improving measures on patients' swallowing function, adherence and quality of life (QOL). Methods: This ongoing trial will explore the difference in adherence and swallowing-related outcome variables during and after PSE in HNC patients performing the same therapy schedule, receiving different delivery methods. One hundred and fifty patients treated in various hospitals will be divided into three groups. Group 1 performs PSE at home, group 2 practices at home with continuous counseling through an app and group 3 receives face-to-face therapy by a speech and language pathologist. The exercises consist of tongue-strengthening exercises and chin-tuck against resistance with effortful swallow. The Iowa Oral Performance Instrument and the Swallowing Exercise Aid are used for practicing. Patients are evaluated before, during and after treatment by means of strength measurements, swallowing and QOL questionnaires. Discussion: Since low adherence rates undermine the positive impact of PSE on post-treatment swallowing function, there is need to develop an efficient PSE protocol maximizing adherence rates

Home ranges, sex ratio and recruitment of the multimammate rat (Mastomys natalensis) in semi-arid areas in Tanzania

Investigation of home ranges, sex ratio and recruitment of the multimammate rat (Mastomys natalensis) in semi-arid areas of Tanzania was conducted in maize and fallow fields using the capture-mark-release (CMR) technique. The aim of this study was to generate useful data for the management of M. natalensis. The relative home range size of M. natalensis was significantly higher during the wet [544 m2±25 standard error (SE)] than during the dry (447 m2 ±18 SE) season, in males (521 m2 ±23 SE) than in females (450 m2 ±17 SE) and in adults (576 m2 ±34 SE) than in juveniles (459 m2 ±16 SE). However, there were no significant differences between habitats. Sex ratio was not significantly different (p=0.44) between habitats. Recruitment was significantly higher (p=0.000) in maize fields (mean=0.43) than in fallow land (mean=0.32) and differed significantly over time (p=0.0001) with the highest recruitment recorded from April to July and the lowest from October to December. Management strategies should focus on managing rodents inhabiting maize fields using methods that affect their recruitment in order to reduce the population increase of M. natalensi

Application of Simple Smart Logic for Waterflooding Reservoir Management

A simple smart logic for controlling inflow control valves (ICV) in waterflooding reservoir management is implemented and analyzed, with the final objective of improving the long term financial return of a petroleum reservoir. Such a control is based in a reactive simple logic that responds to the watercut measured in the ICV. Basically, when the watercut increases, the ICV is set to close proportionally. For comparison purposes, four strategies are presented: base case scenario with conventional control, the best completion configuration found by trial-and-error, the reactive control, and a deterministic optimal control based on Nonlinear Gradient Method with adjoint-gradient formulation is shown for comparison purposes. Finally, all four strategies are tested again in different reservoir realizations in order to mimic the geological uncertainties. Two different synthetic reservoir models were studied. First, a simple cube with a five-spot well configuration, in which the permeability field has a horizontal pattern defined by lognormal distributions. The second model is a benchmark proposed by the Dutch university, TU delft, with 101 channelized permeability fields representing river patterns. For the first model, no significant relative gain is found neither in the variable control nor in the optimal control. Manly because of the high homogeneity of the reservoir models. Therefore, no intelligent completion is recommended. On the other hand, for the second and more complex case, the results indicate an expressive relative gain in the use of simple reactive logic. Besides, this type of control achieves results nearly as good as the optimal control. The test in different realizations, however, shows that reservoir characterization is still a key part of any attempt to improve production. Although the variable reactive control is semi-independent, with action being taken based on measurements, some parameters need a priori model to be tuned

La guerre asymétrique et l'avenir de l'Occident

Asymmetric Warfare and the Future of the West, by Steven METZ Asymmetric warfare is an old phenomenon, but has varied in strategie significance over time. Because the chances of war between major powers is low today, asymmetric conflict has again become important. Today truly is an era of strategie asymmetry. In the realm of military affairs and national security, asymmetry is acting, organising, and thinking differently than an opponent in order to maximise strengths, minimise weaknesses, attain the initiative, or gain freedom of action. It has many different forms and dimensions. Unlike many historic instances of asymmetric conflict, today it is a deliberate choice selected by those weak in conventional military power. It is shaped and driven by the bi-polarity and interconnectedness of the current global security system. Today two forms of asymmetry pose the greatest challenge for Western states: the use of terrorism by non state enemies, and protracted insurgency or internal conflict in weak states. To meet this challenge, Western militaries must revise their organisations and operational concepts to meet the complex challenges of non state terrorism ana protracted internal war.Une ère nouvelle s'est substituée à la guerre froide : celle de la guerre asymétrique. Paradoxalement, c'est l'efficacité des puissances occidentales en matière de guerre conventionnelle qui a poussé leurs adversaires à privilégier des stratégies d'asymétrie (la guérilla, l'insurrection, la guerre prolongée), face auxquelles ces mêmes armées occidentales ne sont ni les plus adaptées ni les plus efficaces. Les Etats occidentaux doivent donc réviser leur approche des questions de sécurité, revoir la place de l'armée dans l'organisation militaire, créer des structures nouvelles (par exemple pour centraliser les ripostes à des cyber-attaques), adapter le cadre normatif et juridique des conflits armés, et surtout consolider leur foi dans leurs valeurs et leurs modèles politiques. L'asymétrie a déplacé l'espace du conflit vers les médias, les manifestations de rue, les Nations unies et autres théâtres de la lutte politique et psychologique. A l'Occident de se montrer, sur ce terrain mouvant, aussi efficace et convaincant que sur le champ de bataille.Metz, Mariën-Casey Chloé. La guerre asymétrique et l'avenir de l'Occident. In: Politique étrangère, n°1 - 2003 - 68ᵉannée. pp. 25-40

Fiber optic biosensing for allergen and pathogen screening in food

Fiber optic biosensing for allergen and pathogen screening in food F. Delport, K. Knez, I. Arghir, N. Marien, D. Spasic, S. Vermeir, J. Lammertyn Point-of-care (POC) diagnostic tests for allergen analysis are expected to deliver fast and sensitive detection of DNA and/or protein targets. However, nowadays, detection of molecular targets alone, without their quantification and/or identification is often insufficient1,2. Although, different assays have been developed to meet these requirements, including quantitative PCR (qPCR)3 followed by high resolution melting analysis as well as ligation assays4, most of them are still largely incompatible with the concept of POC testing due to their cost or complexity. Furthermore, antibody sandwich assays, such as ELISA and lateral flow tests, are the industry standard, but lack kinetics and they need multiple handling steps and another detection setup. In this work, we present the fiber optic (FO) SPR sensor as a flexible platform for multiplex, real-time monitoring of DNA amplification and detection of single nucleotide polymorphisms (SNPs) in a single sample. Furthermore, we report for the first time the selection of aptamers against one of the most important peanut allergens, Ara h1 and the comparison to the antibody based detection (Figure 1). Three approaches of an immunoassay to detect Ara h1 peanut allergens in chocolate candy bars were compared; a label-free assay, a secondary antibody sandwich assay and a nanobead enhanced assay (Figure 1A)5. Although label-free detection is the most convenient, our results illustrate that functionalized nanobeads can offer a refined solution to improve the fiber SPR detection limit. By applying magnetite nanoparticles as a secondary label, the detection limit of the SPR bioassay for Ara h1 was improved by two orders of magnitude from 9 to 0.09 g/mL (Figure 1B). The SPR fibers could be regenerated easily and one fiber could be reused for up to 35 times without loss of sensitivity. The results were benchmarked against a commercially available polyclonal ELISA kit with an excellent correlation, but a longer linear dynamic range. In addition, with the SPR fiber we could measure the samples twice as fast as compared to the fastest ELISA protocol. Several Ara h1 DNA aptamers were selected using capillary electrophoresis (CE)-SELEX6. The selected aptamers specifically recognized Ara h1 and did not significantly bind with other proteins, including another peanut allergen Ara h2. Furthermore, the selected aptamer was used for bioassay development on the FO-SPR biosensor platform for detecting Ara h1 protein in both buffer and food matrix samples demonstrating its real potential for the development of novel, more accurate aptamer-based biosensors. Figure 1. (A) overview of the Ara h1 immunoassay strategies on the fiber optic SPR biosensor. (B) Comparison of the three presented immunoassays on the fiber optic SPR sensor for different Ara h1 concentrations. The error bars indicate standard deviations (n = 3). The aforementioned FO-SPR set-up (Figure 2A) has been used for monitoring the DNA melting profile by implementing DNA functionalized gold nanoparticles (Au NP) as labels (Figure 2B), which allowed discriminating SNPs at high resolution7,8. However, to realize simultaneous quantification and cycle-to-cycle identification of the reaction products, the FO-SPR melting assay was combined either with the PCR or with ligase chain reaction (LCR). The FO-SPR LCR assay amplifies DNA in exponential manner through multiple ligation cycles that progress through 3 succeeding phases: hybridization, ligation and melting phase (Figure 2C). The detection limit of the FO-SPR melting assay was drastically improved using the LCR, whereas capacity for SNP detection was preserved (Figure 2 D,E). Furthermore, to achieve detection of multiple targets within the same sample, FO-SPR melting assay was combined with solution phase PCR using two sets of hybridization probes. The DNA targets in this study were used to discriminate Mycobacterium bovis from Mycobacterium avium subsp. Paratuberculosis. These two bacteria, which are frequently encountered in life stock, were used in a proof-of-concept study that showed the capacity of FO-SPR melting assay for multiplex DNA detection (Figure 2F), thereby further emphasizing the potential of this platform in POC test development. Figure 2. (A) Schematic representation of the FO-SPR setup with all components. (B) Schematic representation of a FO-SPR melting assay (top panel) with DNA target (1) and DNA probes immobilized on the FO-SPR sensor (2) and on Au NP (3). Gene probes hybridize at the FO surface, and are subsequently melted off by a gradual increase of the temperature, resulting in the FO-SPR sensorgram (bottom panel). (C) Schematic overview of the FO-SPR LCR: (1) Different components of the reaction. (2) LCR reaction where the forward and reverse probes are ligated only in the presence of the target sequence, resulting in an exponential amplification during multiple cycles. (3) The forward LCR product can, during the LCR reaction, form a complex with two complementary probes immobilized on the FO-SPR sensor and on Au NPs, allowing real-time monitoring of the reaction. (D) The derived calibration curve with Ct values from the FO-SPR LCR, spans 7 orders of magnitude for DNA concentrations. (E) Obtained signals for WT and MM target DNA using FO-SPR LCR assay (right panel). (F) FO-SPR multiplex PCR, which allows resolving the melting point of the two targets. 1. E. M. Cornett, E. A. Campbell, G. Gulenay, E. Peterson, N. Bhaskar and D. M. Kolpashchikov, Angew Chem Int Ed Engl, 2012, 51, 9075-9077. 2. C. J. Murray and J. A. Salomon, Proceedings of the National Academy of Sciences of the United States of America, 1998, 95, 13881-13886. 3. J. C. Cheng, C. L. Huang, C. C. Lin, C. C. Chen, Y. C. Chang, S. S. Chang and C. P. Tseng, Clinical chemistry, 2006, 52, 1997-2004. 4. S. Sando, H. Abe and E. T. Kool, Journal of the American Chemical Society, 2004, 126, 1081-1087. 5. Pollet, J., Delport, F., Janssen, K., Tran, T., Wouters, J., Verbiest, T., Lammertyn, J., Talanta, 2011, 83, 1436-1441. 6. D. T Tran, K. Knez, K. P. Janssen, J. Pollet, D. Spasic, J. Lammertyn, Biosensors & bioelectronics, 2012, 43, 245-251. 7. J, Pollet, K. Janssen, K. Knez, J.Lammertyn, Small, 2011, 7, 1003-1006 8. K. Knez, K. Janssen, D. Spasic, P. Declerck, L. Vanysacker, C. Denis, T. Tran, J. Lammertyn, Analytical Chemistry,2013, 85, 1734-1742.status: accepte

Determination of anti-neutrophil cytoplasmic antibodies in small vessel vasculitis: Comparative analysis of different strategies

Background Anti-neutrophil cytoplasmic antibodies (ANCA) are associated with primary small vessel vasculitis (SVV). Proteinase-3 (PR3)-ANCA are primarily associated with Wegener granulomatosis, whereas myeloperoxidase (MPO)-ANCA are primarily associated with microscopic polyangiitis (MPA) and vasculitic Churg–Strauss syndrome. We evaluated whether a strategy that is based on screening with ELISA or fluoroenzymeimmunoassay (FEIA) is an accurate alternative to screening with indirect immunofluorescence (IIF). Methods C-ANCA and P-ANCA were determined by IIF and PR3-ANCA and MPO-ANCA were determined by ELISA (Inova) or FEIA (Phadia) on 326 patients (38 with newly diagnosed SVV and 288 diseased controls). Results Specificity and positive likelihood ratios were higher for ELISA and FEIA than for IIF. Post-test probability for SVV of a positive test result was higher for ELISA and FEIA than for IIF. Decision tree analysis in which several testing strategies were compared revealed that a testing strategy that is based on screening with ELISA or FEIA had an expected clinical utility that was comparable to screening with IIF and confirming with ELISA or FEIA. The highest expected clinical utility was found when both IIF and ELISA or FEIA were performed on all samples. Conclusions A strategy based on screening for ANCA with ELISA or FEIA (without prior IIF) is a valuable alternative to screening with IIF and confirming with ELISA or FEIA. Keywords: Vasculitis; Anti-neutrophil cytoplasmic antibodiesstatus: publishe

The Dutch Linguistic Intraoperative Protocol:A valid linguistic approach to awake brain surgery

Intraoperative direct electrical stimulation (DES) is increasingly used in patients operated on for tumours in eloquent areas. Although a positive impact of DES on postoperative linguistic outcome is generally advocated, information about the neurolinguistic methods applied in awake surgery is scarce. We developed for the first time a standardised Dutch linguistic test battery (measuring phonology, semantics, syntax) to reliably identify the critical language zones in detail. A normative study was carried out in a control group of 250 native Dutch-speaking healthy adults. In addition, the clinical application of the Dutch Linguistic Intraoperative Protocol (DuLIP) was demonstrated by means of anatomo-functional models and five case studies. A set of DuLIP tests was selected for each patient depending on the tumour location and degree of linguistic impairment. DuLIP is a valid test battery for pre-, intraoperative and postoperative language testing and facilitates intraoperative mapping of eloquent language regions that are variably located

Aptamer and DNA hybridization assays on gold fiber optic sensors with nanoparticle signal enhancement

Aptamer and DNA hybridization assays on gold fiber optic sensors with nanoparticle signal enhancement F. Delport, K. Knez, K. Janssen, I. Arghir, N. Marien, D.T. Tran, D. Spasic, S. Vermeir, J. Pollet, J. Lammertyn KU Leuven – University of Leuven, BIOSYST - MeBioS, Willem de Croylaan 42, B-3001 Leuven, Belgium Abstract: Detection of allergens and micro bacteria on a fiber optic SPR sensor is performed by means of an oligonucleotide bio-recognition surface. In this work, the DNA surface is optimized by mixing with PEG monolayers to suppress unspecific and enhance specific detection. Furthermore, due to the surface characteristic of DNA functionalized gold nanoparticles the bioassay sensitivity is increased and a mean of real-time multiplexing is introduced. Point-of-care (POC) diagnostic tests for are expected to deliver fast and sensitive detection of DNA and/or protein targets. However, nowadays, detection of molecular targets alone, without their quantification and/or identification is often insufficient1,2. Furthermore, reliable interpretation of the results largely depends on suppressing unspecific binding and carefully designing the surface for maximal specific detection. Although, different assays have been developed to meet these requirements, including quantitative PCR (qPCR)3 followed by high resolution melting analysis as well as ligation assays4, most of them are still largely incompatible with the concept of POC testing due to their cost or complexity. Furthermore, antibody sandwich assays, such as ELISA and lateral flow tests, are the industry standard, but lack kinetic data and they need multiple handling steps and a separate detector. In this talk, the fiber optic (FO) SPR sensor will be presented as a flexible platform for detection of allergens using aptamers and qPCR. Here, we describe an aptamer-based bioassay for detecting one of the most important peanut allergens, Ara h1 and its comparison to the antibody based detection (Figure 1). Furthermore, the FO SPR sensor is applied for multiplex, real-time monitoring of DNA amplification and detection of single nucleotide polymorphisms (SNPs) in a single sample. The importance of balancing the amount of oligonucleotides as bio-recognition molecules on gold surfaces using PEG back filling will be emphasized in this talk through several examples describing different bioassays. The FO-SPR sensor is a translation of the prism based SPR principle to an optical fiber. Although in comparison some sensitivity is reduced, the sensor surface can be used as a consumable bringing SPR sensing to the diagnostic field. As a proof of concept , an FO-SPR bioassay was developed for detecting Ara h1 protein in both buffer and food matrix samples using a DNA aptamer showing high specificity towards Ara h1. Using the selected aptamer, an. A PEG mixed SAM layer was used to functionalize the gold surface and supress nonspecific binding events. Finally, gold nanoparticles (Au NPs) functionalized with antibodies were implemented for signal amplification in a sandwich type bioassay. Fig. 1. Overview of the Ara h1 immunoassay on the FO-SPR biosensor. In this talk, the FO-SPR set-up will be also presented as a platform for monitoring the DNA melting profile. Here, DNA functionalized Au NPs were implemented as labels (Figure 2B), which allowed discriminating SNPs at high resolution6,7 due to the tight packing of DNA molecules on their surface. However, to realize simultaneous quantification and cycle-to-cycle identification of the reaction products, the FO-SPR melting assay was combined either with the PCR or with ligation chain reaction (LCR). To this end, appropriate backfilling of the sensor surface was applied to prevent sticking of the amplification enzymes during the thermal cycling. The FO-SPR LCR assay amplifies DNA in exponential manner through multiple ligation cycles that progress through 3 succeeding phases: hybridization, ligation and melting phase (Figure 2C). Basically two probes are ligated in presence of their target. After denaturing the probe target complex ligation is repeated with their complements. The detection limit of the FO-SPR melting assay was drastically improved compared to the direct melting assay using the LCR, whereas capacity for SNP detection was preserved (Figure 2 D,E). Furthermore, to achieve detection of multiple targets within the same sample, FO-SPR melting assay was combined with solution phase PCR using two sets of hybridization probes. In a proof-of-concept study, two DNA targets were used to discriminate Mycobacterium bovis from Mycobacterium avium subsp. Paratuberculosis, bacteria frequently encountered in life stock (Figure 2F). Backfilling of the gold sensor surface proved to be crucial here for maintaining the high resolution capabilities of the melting detection principle throughout the thermal cycling. Fig. 2. (A) Schematic representation of the FO-SPR setup with all components. (B) Schematic representation of a FO-SPR melting assay (top panel) with DNA target (1) and DNA probes immobilized on the FO-SPR sensor (2) and on Au NPs (3). Gene probes hybridize at the FO surface, and are subsequently melted off by a gradual increase of the temperature, resulting in the FO-SPR sensorgram (bottom panel). (C) Schematic overview of the FO-SPR LCR: (1) Different components of the reaction. (2) LCR reaction where the forward and reverse probes are ligated only in the presence of the target sequence, resulting in an exponential amplification during multiple cycles. (3) The forward LCR product can, during the LCR reaction, form a complex with two complementary probes immobilized on the FO-SPR sensor and on Au NPs, allowing real-time monitoring of the reaction. (D) The derived calibration curve with Ct values from the FO-SPR LCR, spans 7 orders of magnitude for DNA concentrations. (E) Obtained signals for WT and MM target DNA using FO-SPR LCR assay. (F) FO-SPR multiplex PCR, which allows resolving the melting point of the two targets.status: publishe