103 research outputs found

    Influence of distance from the host on parasitisation by Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae)

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    The olive fruit fly, Bactrocera oleae, is considered the main olive pest worldwide, and has been the target of biological control programmes through the release of the braconid parasitoid Psyttalia concolor. Laboratory tests were performed to evaluate the influence of distance from the host on parasitisation, placing larvae of the substitute host Ceratitis capitata at seven distances (0, 0.5, 1, 1.5, 2, 2.5, 3 mm) and four different time periods (7, 15, 30, 60 min). Moreover, field collected olives of Ogliarola Barese cultivar infested by B. oleae were exposed to P. concolor females to confirm its ability to parasitise B. oleae in small olives. Psyttalia concolor oviposition was inhibited at 2.5 and 3 mm due to the ovipositor length of the parasitoid females (2.7 mm). Hosts were easily parasitised at distances between 0 and 1.5 mm. The thin fruit pulp (up to 3.5 mm) of field collected olives allowed the parasitisation to occur also in mature fruits. At the best combination distance/time (0 mm, 30 min), tests performed with different larvae/parasitoid female ratio showed an increasing emergence of P. concolor (from 20% to 57%) with larvae/parasitoid ratio increasing from 0.11 to 0.74. The results of the present study might optimise the mass rearing of P. concolor, through a proper setting of its parameters, such as the host/parasitoid ratio, exposure distances, and interaction time

    Technological addiction in adolescents: the interplay between parenting and psychological basic needs

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    lthough technological addictions, similar to other behavioural addictions, share psychosocial risk factors with substance-related addictions, the studies on the interplay between contextual and personal variables in the prediction of technological addictions are still limited. For this reason, in accordance with Self-Determination Theory (SDT), the aim of this study was to examine the integrated role of parental psychological control and parental autonomy with need satisfaction and need frustration in the understanding of technological addictions (internet addiction, gaming addiction, smartphone addiction, and social network addiction) in adolescents. Using a sample of 482 adolescents (200 males) with an age range between 14 and 17, path analyses showed that both parental psychological control and need frustration predicted all the technological addictions examined. Furthermore, indirect effects from psychological control to all technological addictions through need frustration were also found. The findings are discussed in line with the SDT

    Analisi di fitotossicità e impiego di sansa umida denocciolata in una rotazione farro-cece in regime di agricoltura biologica

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    Pratiche di agricoltura intensiva hanno condotto alla degradazione della risorsa suolo, vale a dire ne hanno diminuito la qualità. Più precisamente, la degradazione riguarda la riduzione della sostanza organica, della stabilità strutturale e della disponibilità di nutrienti nel suolo, con conseguente decremento della produttività. All’interno di un progetto di ricerca in corso, relativo a produzione e impiego di compost in agricoltura biologica, sono previste analisi di fitotossicità su sansa umida denocciolata (SD) poi impiegata in una rotazione farro-cece. L’obiettivo della ricerca è quello di verificare come l’incorporazione al suolo di matrici organiche (M), anche tal quali, può concorrere a mantenere o incrementare la fertilità del suolo ed a sostenere i livelli produttivi delle colture. Nelle analisi di fitotossicità su SD, effettuate con specie test Lepidium sativum L., sono state saggiate oltre alle consuete concentrazioni dell’estratto (50% e 75%), indicate nelle metodiche ufficiali, anche una diluizione maggiore pari al 25% e SD tal quale (100%) centrifugata e filtrata. In una rotazione biennale cece da granella - farro, effettuata a Foggia (campo sperimentale del CRA-SCA) nell’annata agraria 2007-2008, sono stati posti a confronto per ciascuna coltura i seguenti trattamenti: SD tal quale; fertilizzante organo-minerale (OM) ammesso in biologico; controllo non fertilizzato (C). I risultati dei saggi di fitotossicità indicano che la M in esame è risultata fitotossica essendo stato riscontrato un indice di germinazione (Ig) del 44,4%. Dall’esame degli indici calcolati per ciascuna diluizione, inoltre, si è evidenziato come al diminuire della stessa (25%>50%>75%>100%) aumenta l’inibizione all’emergenza e alla crescita radicale (Ig: 66,2%>55,2%>46,9%>9,2%), fino al valore minimo di Ig riscontrato per SD tal quale. Infine, è emerso che la tossicità si esercita a livello di percorsi metabolici diversi, con una netta prevalenza degli effetti sulla lunghezza radicale piuttosto che sul numero di semi germinati. I risultati ottenuti nella prova agronomica hanno evidenziato per il cece una maggiore produzione di granella con OM (2,5 t ha-1) rispetto al trattamento SD (2,1 t ha-1), mentre i valori rilevati per i residui sono paragonabili tra le tre tesi. Le produzioni di granella ottenute per il farro risultano confrontabili, mentre la produzione di paglia è stata maggiore con OM (3,4 e 2,9 t ha-1 rispettivamente per OM e per SD). Da questa attività di ricerca è emerso che SD è una matrice particolare relativamente agli effetti sulle colture, che dovrebbe essere stabilizzata e maturare grazie ad attività di biodegradazione (e quindi compostata in miscela con altre matrici) per poter influenzare positivamente la fertilità del suolo e la produttività delle colture

    Obsessive-Compulsive Aspects and Pathological Gambling in an Italian Sample

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    INTRODUCTION: Gambling behaviour appears as repetitive and difficult to resist and seems to be aimed at neutralizing or reducing negative feelings such as anxiety and tension, confirming its similarities with the obsessive-compulsive spectrum. Aims. Estimating the prevalence of gambling behaviour in an Italian sample and assessing the effects of sociodemographic variables and the correlations between gambling behaviour and obsessive-compulsive features. METHODS: A sample of 300 Italian subjects was evaluated based on gambling behaviours and obsessive-compulsive attitudes. The assessment was carried out in small centers in Italy, mainly in coffee and tobacco shops, where slot machines are located, using the South Oaks Gambling Screen (SOGS) and the MOCQ-R, a reduced form of Maudsley Obsessional-Compulsive Questionnaire. RESULTS: A negative correlation between SOGS and MOPQ-R, with reference to the control and cleaning subscales, was evidenced in the majority of the examined subjects. Both evaluating instruments showed reliability and a good discriminative capacity. CONCLUSIONS: Our study evidenced that the sample of gamblers we analysed did not belong to the obsessive-compulsive disorders area, supporting the validity of the model proposed by DSM-5 for the classification of PG. These data confirm the importance of investing in treatments similar to those used for substance use disorders

    Low-Dose Topiramate in Alcohol Dependence: A Single-Blind, Placebo-Controlled Study

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    Introduction:Topiramate (TOP) and anticonvulsants in general are considered safe and effective drugs for the treatment of alcohol dependence, even though TOP-induced adverse events are quite common, especially for high initial doses or if titration to 300 mg/d is too rapid. The aim of the present study was to assess the efficacy and tolerability profile of low-dose TOP for relapse prevention. METHODS: After detoxification, 52 patients were randomized into 2 groups as follows: 26 patients received 100 mg of TOP (oral, twice daily), titrated over 2 weeks, and 26 patients received placebo (PLA). Both groups underwent rehabilitation twice a week. RESULTS: After 6 weeks of treatment, compared with the PLA group, patients receiving TOP showed the following: (1) fewer drinking days (P < 0.05); (2) less daily alcohol consumption (P < 0.05); (3) more days of treatment (P < 0.05); (4) reduced levels of craving (Obsessive-Compulsive Drinking Scale) and withdrawal symptoms (Clinical Institute Withdrawal Assessment for Alcohol-Revised); and (5) improvement of anxiety, depression, and obsessive-compulsive symptom severity (Symptom Check List 90 Revised). CONCLUSIONS: Despite the small sample size and the short follow-up period, the present PLA-controlled study demonstrated the potential usefulness of TOP, even when administered at a dosage of 100 mg/d, for the treatment of detoxified alcohol-dependent subjects, confirming results from previous studies testing higher doses of TOP
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