13 research outputs found

    Developing a highly stable Carlina acaulis essential oil nanoemulsion for managing Lobesia botrana

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    The growing interest in the development of green pest management strategies is leading to the exploitation of essential oils (EOs) as promising botanical pesticides. In this respect, nanotechnology could efficiently support the use of EOs through their encapsulation into stable nanoformulations, such as nanoemulsions (NEs), to improve their stability and efficacy. This technology assures the improvement of the chemical stability, hydrophilicity, and environmental persistence of EOs, giving an added value for the fabrication of natural insecticides effective against a wide spectrum of insect vectors and pests of public and agronomical importance. Carlina acaulis (Asteraceae) root EO has been recently proposed as a promising ingredient of a new generation of botanical insecticides. In the present study, a highly stable C. acaulis-based NE was developed. Interestingly, such a nanosystem was able to encapsulate 6% (w/w) of C. acaulis EO, showing a mean diameter of around 140 nm and a SOR (surfactant-to-oil ratio) of 0.6. Its stability was evaluated in a storage period of six months and corroborated by an accelerated stability study. Therefore, the C. acaulis EO and C. acaulis-based NE were evaluated for their toxicity against 1st instar larvae of the European grapevine moth (EGVM), Lobesia botrana (Denis & Schiffermüller, 1775) (Lepidoptera: Tortricidae), a major vineyard pest. The chemical composition of C. acaulis EO was investigated by gas chromatography–mass spectrometry (GC–MS) revealing carlina oxide, a polyacetylene, as the main constituent. In toxicity assays, both the C. acaulis EO and the C. acaulis-based NE were highly toxic to L. botrana larvae, with LC50 values of 7.299 and 9.044 µL/mL for C. acaulis EO and NE, respectively. The C. acaulis-based NE represents a promising option to develop highly stable botanical insecticides for pest management. To date, this study represents the first evidence about the insecticidal toxicity of EOs and EO-based NEs against this major grapevine pest

    Developing a highly stable carlina acaulis essential oil nanoemulsion for managing Lobesia Botrana

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    The growing interest in the development of green pest management strategies is leading to the exploitation of essential oils (EOs) as promising botanical pesticides. In this respect, nanotechnology could efficiently support the use of EOs through their encapsulation into stable nanoformulations, such as nanoemulsions (NEs), to improve their stability and efficacy. This technology assures the improvement of the chemical stability, hydrophilicity, and environmental persistence of EOs, giving an added value for the fabrication of natural insecticides effective against a wide spectrum of insect vectors and pests of public and agronomical importance. Carlina acaulis (Asteraceae) root EO has been recently proposed as a promising ingredient of a new generation of botanical insecticides. In the present study, a highly stable C. acaulis-based NE was developed. Interestingly, such a nanosystem was able to encapsulate 6% (w/w) of C. acaulis EO, showing a mean diameter of around 140 nm and a SOR (surfactant-to-oil ratio) of 0.6. Its stability was evaluated in a storage period of six months and corroborated by an accelerated stability study. Therefore, the C. acaulis EO and C. acaulis-based NE were evaluated for their toxicity against 1st instar larvae of the European grapevine moth (EGVM), Lobesia botrana (Denis & Schiffermüller, 1775) (Lepidoptera: Tortricidae), a major vineyard pest. The chemical composition of C. acaulis EO was investigated by gas chromatography–mass spectrometry (GC–MS) revealing carlina oxide, a polyacetylene, as the main constituent. In toxicity assays, both the C. acaulis EO and the C. acaulis-based NE were highly toxic to L. botrana larvae, with LC50 values of 7.299 and 9.044 µL/mL for C. acaulis EO and NE, respectively. The C. acaulis-based NE represents a promising option to develop highly stable botanical insecticides for pest management. To date, this study represents the first evidence about the insecticidal toxicity of EOs and EO-based NEs against this major grapevine pest

    Looking for the Silver Lining: Benefit Finding after Hurricanes Katrina and Rita in Middle-Aged, Older, and Oldest-Old Adults

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    Looking for potentially positive outcomes is one way that people cope with stressful events. In two studies, we examined perceived silver linings after the 2005 Hurricanes Katrina and Rita among indirectly affected adults. In Study 1, middle-aged (ages 47-64 years), older (ages 65-89 years), and oldest-old (ages 90-95 years) adults in the Louisiana Healthy Aging Study (LHAS) responded to an open-ended question on perceived silver linings in a longitudinal assessment carried out during the immediate impact (1 to 4 months after landfall) and post-disaster recovery phase (6 to 14 months post-storm). Qualitative grounded theory methods were employed to analyze these narrative data. Team-based coding yielded three core themes: (1) learning experience and better preparedness for future disasters, (2) having improved cities (Baton Rouge and New Orleans), and (3) an increase in Good Samaritan acts such as strangers helping one another. Responses were similar across age groups, although older adults were the least likely to report positive outcomes. Study 2 was a conceptual replication using a different sample of adults (ages 31 to 82 years) tested at least five years after the storms. A learning experience and preparedness core theme replicated Study 1\u27s findings while improved social cohesion amongst family and friends emerged as a new core theme in Study 2. These data indicate that identifying lessons learned and potentially positive outcomes are psychological reactions that may facilitate post-disaster coping and foster resilience for indirectly affected adults in the years after disaster

    Radiographic changes in alveolar bone height on overdenture abutments: a longitudinal study

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    Objective: Stabilisation of partial dentures is an important part of prosthodontic treatment, particularly in patients with an excessive reduction in alveolar bone supporting their abutment teeth. In these cases, overdenture prostheses are one possible treatment choice. Background: The aim of this study was to evaluate the effects of overdentures on the condition of alveolar bone of the remaining teeth, and to evaluate the overdenture concept in the prosthetic treatment of partially edentulous patients. Materials and methods: The investigation was conducted on 22 patients during observation periods of 6 and 10 years. After preparation, all abutment teeth were provided with either amalgam restorations or gold copings. An overdenture in the lower jaw was fabricated for every patient. A special film holder was used to repeat the X-ray procedure in every patient in the same manner. The radiographs were evaluated using the grid scale. The alveolar bone level of all remaining teeth was evaluated on dental films by measuring the distance between the root apex and coronal border of the alveolar bone. Results: A statistically significant difference (p lt 0.01) was calculated 6 years after delivery stage between distal alveolar bone levels of experimental abutments under overdentures and the remaining teeth of the control group. Alveolar bone of abutment teeth was considerably preserved, particularly in seven patients observed 10 years after provision of their dentures. Conclusion: Within the limitation of this study, the validity of the overdenture treatment in partially edentulous patients is concluded. Good oral hygiene was crucial for the success of treatment with overdentures
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