65 research outputs found
Die gute alte Fruchtfolge als Bekämpfungsmethode gegen den Maiswurzelbohrer (Diabrotica virgifera virgifera LeConte)
Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), the western corn rootworm
(WCR), is an immigrant from North America and one of the top ten global agricultural
pest species. Within the last 15 years, WCR invaded Europe at 3 focal points, and has
been steadily extending its domain soon threatening commercial maize production.
After the first detection in Switzerland in 2000 near Lugano, careful observations by
pheromone trap monitoring of this quarantine organism have been realized.
Experiences with WCR whose populations dynamics are incompletely understood,
have also been studied by installing a continuous maize field comparing population
dynamics with rotated maize fields in the immediate surroundings. Our experiences
with WCR populations in the Swiss territory are here briefly summarized:
1. Mandatory crop rotation in the canton Ticino slowed spread of WCR significantly.
WCR infestations north of the main Alpine mountain chain were rare and eradicated
by crop rotation. 2. In a continuous maize cropping system population of WCR can
reach economic damage level, but can also be confined by unknown factors 3.
Switzerland with its rigorous crop rotation program may serve as an example of farsighted
WCR management preserving environment and saving money
Phylogeny and oscillating expression of period and cryptochrome in short and long photoperiods suggest a conserved function in Nasonia vitripennis
Photoperiodism, the ability to respond to seasonal varying day length with suitable life history changes, is a common trait in organisms that live in temperate regions. In most studied organisms, the circadian system appears to be the basis for photoperiodic time measurement. In insects this is still controversial: while some data indicate that the circadian system is causally involved in photoperiodism, others suggest that it may have a marginal or indirect role. Resonance experiments in the parasitic wasp Nasonia vitripennis have revealed a circadian component in photoperiodic time measurement compatible with a mechanism of internal coincidence where a two components oscillator system obtains information from dawn and dusk, respectively. The identity of this oscillator (or oscillators) is still unclear but possible candidates are the oscillating molecules of the auto-regulatory feedback loops in the heart of the circadian system. Here, we show for the first time the circadian oscillation of period and cryptochrome mRNAs in the heads of Nasonia females kept under short and long photoperiods. Period and cryptochrome mRNA levels display a synchronous oscillation in all conditions tested and persist, albeit with reduced amplitude, during the first day in constant light as well as constant darkness. More importantly, the signal for the period and cryptochrome oscillations is set by the light-on signal. These results, together with phylogenetic analyses, indicate that Nasonia’s period and cryptochrome display characteristics of homologous genes in other hymenopteran species
Heat and charge transport in H2O at ice-giant conditions from ab initio molecular dynamics simulations
The impact of the inner structure and thermal history of planets on their observable features, such as luminosity or magnetic field, crucially depends on the poorly known heat and charge transport properties of their internal layers. The thermal and electric conductivities of different phases of water (liquid, solid, and super-ionic) occurring in the interior of ice giant planets, such as Uranus or Neptune, are evaluated from equilibrium ab initio molecular dynamics, leveraging recent progresses in the theory and data analysis of transport in extended systems. The implications of our findings on the evolution models of the ice giants are briefly discussed
Evidence for positive selection in the gene fruitless in Anastrepha fruit flies
<p>Abstract</p> <p>Background</p> <p>Many genes involved in the sex determining cascade have indicated signals of positive selection and rapid evolution across different species. Even though <it>fruitless </it>is an important gene involved mostly in several aspects of male courtship behavior, the few studies so far have explained its high rates of evolution by relaxed selective constraints. This would indicate that a large portion of this gene has evolved neutrally, contrary to what has been observed for other genes in the sex cascade.</p> <p>Results</p> <p>Here we test whether the <it>fruitless </it>gene has evolved neutrally or under positive selection in species of <it>Anastrepha </it>(Tephritidae: Diptera) using two different approaches, a long-term evolutionary analysis and a populational genetic data analysis. The first analysis was performed by using sequences of three species of <it>Anastrepha </it>and sequences from several species of <it>Drosophila </it>using the ratio of nonsynonymous to synonymous rates of evolution in PAML, which revealed that the <it>fru </it>region here studied has evolved by positive selection. Using Bayes Empirical Bayes we estimated that 16 sites located in the connecting region of the <it>fruitless </it>gene were evolving under positive selection. We also investigated for signs of this positive selection using populational data from 50 specimens from three species of <it>Anastrepha </it>from different localities in Brazil. The use of standard tests of selection and a new test that compares patterns of differential survival between synonymous and nonsynonymous in evolutionary time also provide evidence of positive selection across species and of a selective sweep for one of the species investigated.</p> <p>Conclusions</p> <p>Our data indicate that the high diversification of <it>fru </it>connecting region in <it>Anastrepha </it>flies is due at least in part to positive selection, not merely as a consequence of relaxed selective constraint. These conclusions are based not only on the comparison of distantly related taxa that show long-term divergence time, but also on recently diverged lineages and suggest that episodes of adaptive evolution in <it>fru </it>may be related to sexual selection and/or conflict related to its involvement in male courtship behavior.</p
A gestural repertoire of 1-2year old human children : in search of the ape gestures
This project was made possible with the generous financial help of the Baverstock Bequest to the Psychology and Neuroscience Department at the University of St Andrews.When we compare human gestures to those of other apes, it looks at first like there is nothing much to compare at all. In adult humans, gestures are thought to be a window into the thought processes accompanying language, and sign languages are equal to spoken language with all of its features. While some research firmly emphasises the difference between human gestures and those of other apes, the question about whether there are any commonalities has rarely been investigated, and is mostly confined to pointing gestures. The gestural repertoires of nonhuman ape species have been carefully studied and described with regard to their form and function – but similar approaches are much rarer in the study of human gestures. This paper applies the methodology commonly used in the study of nonhuman ape gestures to the gestural communication of human children in their second year of life. We recorded (n=13) children’s gestures in a natural setting with peers and caregivers in Germany and Uganda. Children employed 52 distinct gestures, 46 (89%) of which are present in the chimpanzee repertoire. Like chimpanzees, they used them both singly, and in sequences; and employed individual gestures flexibly towards different goals.Publisher PDFPeer reviewe
People with mental illness can tackle tobacco
Objective: To evaluate a smoking reduction and cessation intervention tailored for people with significant disability associated with mental illness. Method: The intervention was a 10 week group programme, which tailored smoking cessation interventions to the needs of people living with mental illness. It was facilitated by mental health workers and peer workers and was promoted through mental health services, general practitioners and the Quitline phone service. Participants were people living with mental illness who had asked for help to quit or reduce their tobacco use. Participants were interviewed before starting the course, twice during the course and at 3, 6 and 12 months post course completion. Results: Overall, 226 people expressed interest, 183 attended at least one session of the course and 105 attended at least 10 sessions. Of the 183 participants, 79.8% reported they did not smoke for at least 24 hours, with 30.6% stopping for at least 30 days. At the 12 month follow up 16.6% of participants reported they were not smoking. Of the 105 participants who attended at least 10 sessions of the course, 85.7% reported they did not smoke for at least 24 hours and 37.1% stopping for at least 30 days. At 12 month follow up 21.3% reported they were not smoking. Cigarettes smoked per day declined among those who did not quit, and was still significantly lower after 12 months. Motivation to try to quit was high among those still smoking at 12 months, with 83.9% wanting to try again to quit. Conclusions: This programme has shown many people with significant disability associated with mental illness are motivated to attend a smoking reduction and cessation group programme. A programme tailored to meet the specific needs of this group can be effective in helping many to quit or reduce their tobacco use.Maxie Ashton, Caroline L. Miller, Jacqueline A. Bowden, Sue Bertoss
Contributo teorico-sperimentale sui sistemi di trasporto pneumatico ad alto rapporto di miscela
Preliminarmente vengono esaminati i componenti essenziali e la costruzione di un trasportatore a spinta pneumatica sperimentale, gi\ue0 realizzato presso il Dipartimento di Energetica dell'Universit\ue0 degli Studi di Trieste, con ampie caratteristiche di flessibilit\ue0 operativa.
Successivamente, segue un'analisi teorica del fenomeno che regola la spinta propulsiva del materiale estendendola alla caratterizzazione dei principali parametri funzionali significativi nel proporzionamento di questo tipo di impianti.
L'impianto pilota \ue8 stato dotato di un sofisticato sistema di rilevamento delle grandezze oggetto dell'indagine ed interconnesso con un sistema di acquisizione dati che consente di seguire in tempo reale e memorizzare l'evolversi dei fenomeni alla base del funzionamento.
Vengono infine presentati i primi risultati sperimentali applicativi di specifiche indagini sui componenti
Primi rilievi sperimentali su un impianto di trasporto pneumatico a spinta
Dopo una breve descrizione dell'impianto sperimentale di trasporto a spinta pneumatica realizzato presso il Dipartimento di Energetica dell'Universit\ue0 di Trieste, e aver definito le equazioni generali del moto, viene illustrato il sistema di acquisizione dati e la relativa componentistica utilizzata per i rilievi sperimentali.
Sono inoltre presentati i primi rilievi sperimentali ottenuti in questa fase al fine di verificare il comportamento di tutto il sistema di rilevamento, acquisizione, registrazione ed elaborazione dati e confrontarli con i risultati ottenibili dall'elaborazione teorica
CA125 production by the peritoneum: in-vitro and in-vivo studies
The source of CA125 synthesis is still debated. Endometrial, peritoneal, ovarian and amniotic cells have been demonstrated to produce and secrete CA125. Different studies show that the peritoneum is a source of CA125. The present study aimed at investigating in vivo and in vitro the peritoneal contribution to circulating CA125. Cultures of uterine peritoneum, abdominal peritoneum and myometrium explants were performed and CA125 measured in the culture medium. To modulate the potential production of CA125, the explants were cultured with or without cycloheximide, bacterial lipopolysaccharide (LPS) or ascitic fluid. In a prospective study, we compared a group of patients after abdominal surgery (n = 19; nine men, 10 women) with a group after extra-abdominal surgery (n = 21; 11 men, 10 women), in order to detect a postoperative increase of serum CA125. De-novo synthesis of CA125 could not be demonstrated in the cultures of uterine and abdominal peritoneum and in myometrium, but CA125 concentrations were detectable in the culture medium without being modulated by cycloheximide, LPS or ascitic fluid. After peritoneal surgery, the proportion of patients with increased serum CA125 was significantly higher (P < 0.03) after abdominal surgery as compared with extra-abdominal surgery. This is considered as indirect evidence for in-vivo production of CA125 by the peritoneu
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