292 research outputs found
Intraguild predation between lady beetles and lacewings: outcomes and consequences vary with focal prey and arena of interaction
Citation: Noppe, Christophe, J. P. Michaud, and Patrick De Clercq. 2012. “Intraguild Predation Between Lady Beetles and Lacewings: Outcomes and Consequences Vary With Focal Prey and Arena of Interaction.” Annals of the Entomological Society of America 105 (4): 562–71. https://doi.org/10.1603/AN11165.We examined reciprocal intraguild predation (IGP) and cannibalism among various combinations of Coleomegilla maculata DeGeer and Chrysoperla carnea Stephens larvae as they developed feeding on greenbugs, Schizaphis graminum Rondani, on sorghum plants in microcosms. Pairs of C. maculata larvae suppressed aphids better than pairs of C. carnea larvae or heterospecific larval pairs and yielded the highest rate of plant survival. IGP by C. carnea larvae occurred mostly in the first instar, whereas C. maculata larvae were more aggressive in later instars. Although C. carnea was the superior intraguild predator, winning 62.7% of contests in microcosms, this value increased to 88.9% when the experiment was repeated in petri dishes without plant material, regardless of whether greenbugs or eggs of Ephestia kuehniella Zeller were offered as focal prey. Provision in petri
dishes of the sessile, higher quality prey (Ephestia) as opposed to greenbugs, improved the survival of solitary larvae and delayed cannibalism and IGP until later developmental stages in both species. Larvae of C. maculata that cannibalized took longer to develop and weighed less at pupation,
independent of the arena or prey offered. Although larvae of C. carnea did not pay a cost for cannibalism or IGP in microcosms, there were some negative developmental effects of IGP in petri dishes, particularly on the Ephestia diet. These results illustrate how the plant, as a substrate, can
mediate the strength of IGP interactions and how the relative suitability of the focal prey can influence both the timing and consequences of cannibalism and IGP
Glocalisation
Deze bundel brengt verslag uit van de tweedaagse conferentie die de Stichting Maatschappij en Veiligheid uit Nederland (SMV) en het Centrum voor Politiestudies uit België (CPS) organiseerden op 12 en 13 december 2013 in Deinze. De conferentie had als thema "Tides and currents in police theories", waarbij het de bedoeling was te reflecteren over hoe er tegenwoordig wordt gedacht over politie, met andere woorden over de onderliggende stromen en evoluties in politietheorieën. Rond ditzelfde thema werd tevens een Cahier Politiestudies samengesteld dat op de tweedaagse conferentie aan de deelnemers en sprekers werd aangeboden3. Het thema van de conferentie en het Cahier was gebaseerd op een paper van Jack Greene "The Tides and Currents, Eddies and Whirlpools and Riptides of Modern Policing: Connecting Thoughts". Deze paper werd geschreven naar aanleiding van een seminarie dat plaatsvond bij de Universiteit Gent in het kader van de werkgroep "politie" van de European Society of Criminology (ESC) in september 2010. Met deze conferentie wilden we de analyse verder doortrekken en kwamen naast de theoretische inzichten ook de beleidsmatige implicaties ervan aan bod. Met deze publicatie willen we de rijke discussies die zich ontwikkelden ter gelegenheid van deze conferentie onder de aandacht van de geïnteresseerden brengen en continuëren. De publicatie is deels in het Nederlands, deels in het Engels, waarbij we de auteurs vrij lieten de taal van hun voorkeur te hanteren.The politics and administration of institutional chang
Occurrence of pharmaceuticals in environmental samples: a multi-analyte approach
Pharmaceuticals and their residues in the environment have been recently recognized as one of the emerging research areas in the environmental chemistry and toxicology and caused them to be viewed as a new class of priority substances. It has been reportedthat they are introduced continuously in the environment via household use, effluents from Sewage Treatment Plants (STPs) and animal excreta. Up to date, the potential human, animal and ecological risk associated with the occurrence of these compounds in the environment is not well documented. There is an increased attention due to the fact that they are designed to have specific effects at low doses and to be resistant to Moreover, the science of mixture toxicity is complex and to date quite unknown (Bound et al., 2006; Hernando et al., 2006).Despite the increased research and regulatory interest in the occurrence of pharmaceuticals and their degradation products in STPs effluents and freshwater ecosystems (Hernando et al., 2006), the occurrence, the distribution between the different environmental compartments (i.e. water, sediments, suspended solids and aqueous organisms), the trophic transfer and their potential toxicity is to date far less documented (Emblidge and DeLorenze, 2006).In this sense, this study will present a detection method for the determination of a large group of pharmaceuticals (i.e. antibiotics, beta-agonists, painkillers, tranquilizers, nonsteroidal anti-inflammatory drugs) used both in human and veterinary practice in environmental samples using Liquid Chromatography coupled to multiple Mass Spectrometry
Contact inhibition of locomotion and mechanical cross-talk between cell-cell and cell-substrate adhesion determines the pattern of junctional tension in epithelial cell aggregates
We generated a computational approach to analyze the biomechanics of
epithelial cell aggregates, either island or stripes or entire monolayers, that
combines both vertex and contact-inhibition-of-locomotion models to include
both cell-cell and cell-substrate adhesion. Examination of the distribution of
cell protrusions (adhesion to the substrate) in the model predicted high order
profiles of cell organization that agree with those previously seen
experimentally. Cells acquired an asymmetric distribution of basal protrusions,
traction forces and apical aspect ratios that decreased when moving from the
edge to the island center. Our in silico analysis also showed that tension on
cell-cell junctions and apical stress is not homogeneous across the island.
Instead, these parameters are higher at the island center and scales up with
island size, which we confirmed experimentally using laser ablation assays and
immunofluorescence. Without formally being a 3-dimensional model, our approach
has the minimal elements necessary to reproduce the distribution of cellular
forces and mechanical crosstalk as well as distribution of principal stress in
cells within epithelial cell aggregates. By making experimental testable
predictions, our approach would benefit the mechanical analysis of epithelial
tissues, especially when local changes in cell-cell and/or cell-substrate
adhesion drive collective cell behavior.Comment: 39 pages, 8 Figures. Supplementary Information is include
Determination of pharmaceuticals in water samples of the Belgian coastal zone and the Scheldt Estuary using LC-MS
Treatment and outcome of fracture-related infection of the clavicle
Introduction: The number of operatively treated clavicle fractures has increased over the past decades. Consequently, this has led to an increase in secondary procedures required to treat complications such as fracture-related infection (FRI). The primary objective of this study was to assess the clinical and functional outcome of patients treated for FRI of the clavicle. The secondary objectives were to evaluate the healthcare costs and propose a standardized protocol for the surgical management of this complication. Methods: All patients with a clavicle fracture who underwent open reduction and internal fixation (ORIF) between 1 January 2015 and 1 March 2022 were retrospectively evaluated. This study included patients with an FRI who were diagnosed and treated according to the recommendations of a multidisciplinary team at the University Hospitals Leuven, Belgium. Results: We evaluated 626 patients with 630 clavicle fractures who underwent ORIF. In total, 28 patients were diagnosed with an FRI. Of these, eight (29%) underwent definitive implant removal, five (18%) underwent debridement, antimicrobial treatment and implant retention, and fourteen patients (50%) had their implant exchanged in either a single-stage procedure, a two-stage procedure or after multiple revisions. One patient (3.6%) underwent resection of the clavicle. Twelve patients (43%) underwent autologous bone grafting (tricortical iliac crest bone graft (n = 6), free vascularized fibular graft (n = 5), cancellous bone graft (n = 1)) to reconstruct the bone defect. The median follow-up was 32.3 (P25-P75: 23.9–51.1) months. Two patients (7.1%) experienced a recurrence of infection. The functional outcome was satisfactory, with 26 out of 28 patients (93%) having full range of motion. The median healthcare cost was € 11.506 (P25-P75: € 7.953–23.798) per patient. Conclusion: FRI is a serious complication that can occur after the surgical treatment of clavicle fractures. In our opinion, when treated adequately using a multidisciplinary patient-specific approach, the outcome of patients with an FRI of the clavicle is good. The median healthcare costs of these patients are up to 3.5 times higher compared to non-infected operatively treated clavicle fractures. Although not studied individually, we consider factors such as the size of the bone defect, condition of the soft tissue, and patient demand important when it comes to guiding our surgical decision making in cases of osseous defects.</p
Treatment and outcome of fracture-related infection of the clavicle
Introduction: The number of operatively treated clavicle fractures has increased over the past decades. Consequently, this has led to an increase in secondary procedures required to treat complications such as fracture-related infection (FRI). The primary objective of this study was to assess the clinical and functional outcome of patients treated for FRI of the clavicle. The secondary objectives were to evaluate the healthcare costs and propose a standardized protocol for the surgical management of this complication. Methods: All patients with a clavicle fracture who underwent open reduction and internal fixation (ORIF) between 1 January 2015 and 1 March 2022 were retrospectively evaluated. This study included patients with an FRI who were diagnosed and treated according to the recommendations of a multidisciplinary team at the University Hospitals Leuven, Belgium. Results: We evaluated 626 patients with 630 clavicle fractures who underwent ORIF. In total, 28 patients were diagnosed with an FRI. Of these, eight (29%) underwent definitive implant removal, five (18%) underwent debridement, antimicrobial treatment and implant retention, and fourteen patients (50%) had their implant exchanged in either a single-stage procedure, a two-stage procedure or after multiple revisions. One patient (3.6%) underwent resection of the clavicle. Twelve patients (43%) underwent autologous bone grafting (tricortical iliac crest bone graft (n = 6), free vascularized fibular graft (n = 5), cancellous bone graft (n = 1)) to reconstruct the bone defect. The median follow-up was 32.3 (P25-P75: 23.9–51.1) months. Two patients (7.1%) experienced a recurrence of infection. The functional outcome was satisfactory, with 26 out of 28 patients (93%) having full range of motion. The median healthcare cost was € 11.506 (P25-P75: € 7.953–23.798) per patient. Conclusion: FRI is a serious complication that can occur after the surgical treatment of clavicle fractures. In our opinion, when treated adequately using a multidisciplinary patient-specific approach, the outcome of patients with an FRI of the clavicle is good. The median healthcare costs of these patients are up to 3.5 times higher compared to non-infected operatively treated clavicle fractures. Although not studied individually, we consider factors such as the size of the bone defect, condition of the soft tissue, and patient demand important when it comes to guiding our surgical decision making in cases of osseous defects.</p
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