HOUSEHOLDS' EXPERIENCES WITH THE RED IMPORTED FIRE ANT IN SOUTH CAROLINA

The red imported fire ant (Solenopsis invicta), abbreviated as RIFA, is believed to have been brought by accident to Mobile, Alabama in the 1930s via ship ballast from South America. The RIFA was first reported in Charleston and Orangeburg counties in South Carolina in 1952 and has since spread to all 46 counties in the state. The RIFA has had adverse impacts on the environments it has infested. In natural environments, the young of ground-nesting insects, reptiles, birds and mammals are subject to RIFA predation. In agriculture, the RIFA damages crops and livestock. The RIFA poses a health threat to humans, as it is aggressive and has a venomous sting. To learn more about the current impacts of the RIFA, a random sample of South Carolina households was conducted between November 1998 and January 1999. This report summarizes the survey results.Environmental Economics and Policy,

Professionalisering van de wegenbouw – Het effect van de verdichtingstemperatuur op kwaliteitsparameters en de consequenties voor wegenbouwprocessen

Als respons op velerlei veranderingen in de wegenbouw is het netwerk ASPARi gericht op de professionalisering van de sector. In ASPARi-verband is bij Ooms Nederland Holding bv onderzoek verricht naar het effect van de temperatuur waarbij een asfaltmengsel verdicht wordt op de uiteindelijk functionele mechanische eigenschappen. Deze relatie is van belang voor het ‘verdichtingsvenster’: De temperaturen waarbinnen idealiter de verdichting plaatsvindt. Dat de temperatuur van het asfaltmengsel en de verdichtingsprocedure belangrijk zijn voor de eindkwaliteit van de asfaltverharding is al langer algemeen bekend. Traditioneel wordt zo’n verdichtingvenster gebaseerd op de viscositeit in een temperatuurbereik en de dichtheid die bij een gegeven viscositeit behaald kan worden. De uitkomsten van dit onderzoek laten zien dat het verstandig is om te werken met verdichtingsvensters en deze te bepalen aan de hand van beoogde mechanische \ud eigenschappen van de asfaltverharding. Verder blijkt dat de temperatuur waarop een asfaltmengsel verdicht wordt, sterk van belang is voor de eindkwaliteit van de asfaltverharding. Verdichten buiten het temperatuurvenster kan een vermindering van de eindkwaliteit tot gevolg hebben, en dus levensduurverkorting. Een kortere levensduur en eerdere schades aan het wegdek leiden tot reparatie, extra kosten, verminderde beschikbaarheid en mogelijk discussie over de garantie en dus financiële afrekening van het werk. Daarom wordt in deze paper voorgesteld het klassieke principe aan te scherpen. Hierbij wordt voorgesteld het verdichtingsvenster niet alleen aan de hand van de \ud streefdichtheid vast te stellen, maar ook aan de hand van de beoogde mechanische eigenschappen die uiteindelijk behaald moeten worden. In lijn daarmee zijn vervolgstappen richting professionalisering wenselijk en noodzakelijk om de eindkwaliteit verder te kunnen verbeteren en om tijdens het proces tijdig te kunnen bijsturen. Deze paper geeft daartoe aanleiding en aanwijzingen.\u

Neonatal oxytocin administration and weaning onto a gruel based diet reduce weight loss at weaning and enhance gastric leptin expression

Administering oxytocin to neonatal rats has positive long-term effects on growth and development (Uvnas-Moberg and Petersson, 2005). These effects include a reduction in the stress response to weaning, increased post-weaning feed intake and alterations in the expression of gastrointestinal (GI) hormones regulating feed intake (Uvnas-Moberg et al., 1998; Sohlstrom et al., 1999). Two GI hormones of importance in regulating feed intake are ghrelin and leptin, which have antagonistic actions. Ghrelin expression is increased in response to fasting and leptin expression increases rapidly in response to feed intake. Since weaning the piglet is associated with stress and growth restriction, this study examined whether oxytocin given to young pigs could reduce the extent of the post-weaning growth check, along with any associated changes in ghrelin and leptin expression

Using cascading Bloom filters to improve the memory usage for de Brujin graphs

De Brujin graphs are widely used in bioinformatics for processing next-generation sequencing data. Due to a very large size of NGS datasets, it is essential to represent de Bruijn graphs compactly, and several approaches to this problem have been proposed recently. In this work, we show how to reduce the memory required by the algorithm of [3] that represents de Brujin graphs using Bloom filters. Our method requires 30% to 40% less memory with respect to the method of [3], with insignificant impact to construction time. At the same time, our experiments showed a better query time compared to [3]. This is, to our knowledge, the best practical representation for de Bruijn graphs.Comment: 12 pages, submitte

Hydra: A Parallel Adaptive Grid Code

We describe the first parallel implementation of an adaptive particle-particle, particle-mesh code with smoothed particle hydrodynamics. Parallelisation of the serial code, ``Hydra'', is achieved by using CRAFT, a Cray proprietary language which allows rapid implementation of a serial code on a parallel machine by allowing global addressing of distributed memory. The collisionless variant of the code has already completed several 16.8 million particle cosmological simulations on a 128 processor Cray T3D whilst the full hydrodynamic code has completed several 4.2 million particle combined gas and dark matter runs. The efficiency of the code now allows parameter-space explorations to be performed routinely using $64^3$ particles of each species. A complete run including gas cooling, from high redshift to the present epoch requires approximately 10 hours on 64 processors. In this paper we present implementation details and results of the performance and scalability of the CRAFT version of Hydra under varying degrees of particle clustering.Comment: 23 pages, LaTex plus encapsulated figure

The Origin and Early Cultivation of Sorghums in Africa.

30 p

The discovery of ash dieback in the UK: the making of a focusing event

Why did the identification of ‘Ash Dieback’ (Chalara Fraxinea) in 2012 in the UK catch the national media, public and political zeitgeist, and lead to policy changes, in a way that no other contemporary tree pest or pathogen outbreak has?The identification of Ash Dieback in the UK is conceptualised as a successful ‘focusing event’ and the ways in which it was socially constructed by the media, stakeholders and the government are analysed. National newspaper coverage contributed to the way that the disease was understood and was significant in driving the political response. Ash Dieback’s focal power derived from the perceived scale and nature of its impact; the initial attribution of blame on government; the ‘war-like’ response from the government; and Ash’s status as a threatened ‘native’ tree. The Ash Dieback focusing event has increased the salience of plant health issues amongst policymakers, the public and conservation organisations in the UK