The phenology and population dynamics of Culicoides spp. in different ecosystems in the Netherlands

The Netherlands has enjoyed a relatively free state of vector-borne diseases of economic importance for more than one century. Emerging infectious diseases may change this situation, threatening the health of humans, domestic livestock and wildlife. In order to be prepared for the potential outbreak of vector-borne diseases, a study was undertaken to investigate the distribution and seasonal dynamics of candidate vectors of infectious diseases with emphasis on bluetongue vectors (Culicoides spp.). The study focused primarily on the relationship between characteristic ecosystems suitable for bluetongue vectors and climate, as well as on the phenology and population dynamics of these vectors. Twelve locations were selected, distributed over four distinct habitats: a wetland area, three riverine systems, four peat land areas and four livestock farms. Culicoides populations were sampled continuously using CO2-baited counterflow traps from July 2005 until August 2006, with an interruption from November 2005 to March 2006. All vectors were identified to species level. Meteorological and environmental data were collected at each location. Culicoides species were found in all four different habitat types studied. Wetland areas and peat bogs were rich in Culicoides spp. The taxonomic groups Culicoides obsoletus (Meigen) and Culicoides pulicaris (Linnaeus) were strongly associated with farms. Eighty-eight percent of all Culicoides consisted of the taxon C. obsoletus/Culicoides scoticus. On the livestock farms, 3% of Culicoides existed of the alleged bluetongue vector Culicoides dewulfi Goetghebuer. Culicoides impunctatus Goetghebuer was strongly associated with wetland and peat bog. Many Culicoides species were found until late in the phenological season and their activity was strongly associated with climate throughout the year. High annual variations in population dynamics were observed within the same study areas, which were probably caused by annual variations in environmental conditions. The study demonstrates that candidate vectors of bluetongue virus are present in natural and livestock-farm habitats in the Netherlands, distributed widely across the country. Under favourable climatic conditions, following virus introduction, bluetongue can spread among livestock (cattle, sheep and goats), depending on the nature of the viral serotype. The question now arises whether the virus can survive the winter conditions in north-western Europe and whether measures can be taken that effectively halt further spread of the disease

Use of a mobile platform for assessing urban heat stress in Rotterdam

In this study, an assessment of the intensity of the urban heat island (UHI) in Rotterdam was carried out using an innovative mobile bio-meteorological measuring platform mounted on a cargo bicycle. The goal was to assess whether or not heat stress is currently or likely to become a critical issue. Physiological equivalent temperatures were calculated directly from the measurements. Preliminary results show how effective urban parks and greenery are in reducing the UHI. The maximum UHI was about 7 K warmer than the rural area, whereas greener urban configurations were under 3 K warmer. City parks show marked cooling effects during daytime. The preliminary results clearly demonstrate the presence of a considerable UHI in Rotterdam, which is expected to be found in other Dutch cities, and confirms the important role of green spaces in mitigating urban heat stress

Gemeten actuele verdamping voor twaalf locaties in Nederland

Stowa heeft Alterra de opdracht gegeven jaarreeksen van actuele dagelijkse verdamping af te leiden voor twaalf meetlocaties in Nederland. Daarbij is gebruik gemaakt van bestaande (micro)meteorologische meetgegevens. De meetgegevens zijn gecontroleerd op kwaliteit en continuïteit en ontbrekende dagtotalen zijn aangevuld met door een Artificieel Neuraal Netwerk gesimuleerde gegevens. De onzekerheid in de jaartotalen van de bepaalde actuele verdamping ligt tussen de 10 en 15%

Lack of evidence for western flower thrips biotypes base don intra and inter-strain variation in gut bacteria

Western flower thrips is a polyphagous insect, which during the last 30 years has become a world wide pest. It was found earlier that these thrips are associated with a type of Erwinia species gut bacteria. In this study we examine the variation of bacteria within and between thrips individuals and try to find evidence for biotypes in western flower thrips regarding the type of gut bacteria. The existence of biotypes in this thrips species has been suggested by different authors. For example, thrips populations have been found that differ in resistance against pesticides and in their ability to transmit plant viruses. With biotypes we mean groups of individuals (strains, populations, lines) of a species which differ in one or more traits with other groups of that species. The gut bacteria of thrips are acquired by young thrips larvae via the host plant and have a beneficial effect on thrips development and oviposition. We studied thrips strains from different countries and host plants, and the isofemale lines that were created from them, on bean plant leaves. All thrips lines that we studied contained Erwinia species gut bacteria. Morphological and biochemical characteristics of gut bacteria from the thrips isofemale lines were similar to the Erwinia type strain from the reference, a thrips strain cultured on chrysanthemum in Amsterdam (TAC 93.XII.8). Per isofemale line we studied five thrips individuals and per thrips we studied four bacterial colonies, with RAPD markers. The genetic variation between bacteria isolated from thrips was as large among isofemale lines as within isofemale lines. No evidence for thrips biotypes was found. Bacteria within one thrips individual show a stronger degree of similarity than bacteria from different thrips individuals within a single rearing. This is probably due to a bottleneck caused by the limited number of successful infections of bacteria into the gut of the thrip

Modelling and observing urban climate in the Netherlands

Volgens de klimaatscenario’s van het KNMI uit 2006 zal de gemiddelde temperatuur in Nederland in de komende decennia verder stijgen. Hittegolven zullen naar verwachting vaker voorkomen en de intensiteit van met name zomerse buien kan toenemen. In steden zijn de gevolgen van de opwarming extra voelbaar, omdat de temperaturen er door het zogenoemde Urban Heat Island (UHI) effect veel hoger kunnen zijn dan in het omliggende gebied. Zulke periodes met hoge temperaturen gaan veelal gepaard met verslechterde luchtkwaliteit en droogte. Dit alles kan grote gevolgen hebben voor de leefbaarheid en de gezondheid van de bevolking in stedelijke gebieden. Veranderingen in de buienintensiteit beïnvloeden de waterhuishouding van de stad

Assessing pain in patients with severe cerebral palsy: Development, reliability, and validity of a pain assessment instrument for cerebral palsy

Boldingh, EJ, Jacobs-van der Bruggen MA, Lankhorst GJ, Bouter LM. Assessing pain in patients with severe cerebral palsy: development, reliability, and validity of a pain assessment instrument for cerebral palsy. Arch Phys Med Rehabil 2004;85:758-66. Objectives To develop the Pain Assessment Instrument for Cerebral Palsy (PAICP) and to study its test-retest reproducibility and construct validity. Design Cross-sectional validation study. Setting Homes for severely handicapped. Participants A total of 164 adults with severe cerebral palsy (CP), caregivers, and physiotherapists, and 9 healthy children. Interventions The PAICP contains drawings of situations, some situations of which usually produce pain. Patients rate the pain associated with each activity using a Faces Pain Scale. Reproducibility and construct validity was assessed in a pilot study with CP patients and healthy children. Construct validity and agreement between the pain scores of the patients and proxies was assessed in 160 patients with severe CP. Main outcome measure Pain score on the PAICP. Results The measure showed adequate test-retest reproducibility. A significant difference was found between the mean scores for "painful" and "not painful" situations. We also found moderate agreement between the scores of the patients and proxies for daily activities but only for those activities in which the proxies were personally involved. Conclusions The PAICP has adequate test-retest reproducibility and construct validity. It provides an indication of the pain experienced by patients in situations in which proxies are not personally involved and may also be more valid than proxy measures for other situations. © 2004 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Involutive Categories and Monoids, with a GNS-correspondence

This paper develops the basics of the theory of involutive categories and shows that such categories provide the natural setting in which to describe involutive monoids. It is shown how categories of Eilenberg-Moore algebras of involutive monads are involutive, with conjugation for modules and vector spaces as special case. The core of the so-called Gelfand-Naimark-Segal (GNS) construction is identified as a bijective correspondence between states on involutive monoids and inner products. This correspondence exists in arbritrary involutive categories

Structural Evolution of Gene Promoters Driven by Primate-Specific KRAB Zinc Finger Proteins

Krüppel-associated box (KRAB) zinc finger proteins (KZNFs) recognize and repress transposable elements (TEs); TEs are DNA elements that are capable of replicating themselves throughout our genomes with potentially harmful consequences. However, genes from this family of transcription factors have a much wider potential for genomic regulation. KZNFs have become integrated into gene-regulatory networks through the control of TEs that function as enhancers and gene promoters; some KZNFs also bind directly to gene promoters, suggesting an additional, more direct layer of KZNF co-option into gene-regulatory networks. Binding site analysis of ZNF519, ZNF441, and ZNF468 suggests the structural evolution of KZNFs to recognize TEs can result in coincidental binding to gene promoters independent of TE sequences. We show a higher rate of sequence turnover in gene promoter KZNF binding sites than neighboring regions, implying a selective pressure is being applied by the binding of a KZNF. Through CRISPR/Cas9 mediated genetic deletion of ZNF519, ZNF441, and ZNF468, we provide further evidence for genome-wide co-option of the KZNF-mediated gene-regulatory functions; KZNF knockout leads to changes in expression of KZNF-bound genes in neuronal lineages. Finally, we show that the opposite can be established upon KZNF overexpression, further strengthening the support for the role of KZNFs as bona-fide gene regulators. With no eminent role for ZNF519 in controlling its TE target, our study may provide a snapshot into the early stages of the completed co-option of a KZNF, showing the lasting, multilayered impact that retrovirus invasions and host response mechanisms can have upon the evolution of our genomes