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1.
Proc Biol Sci ; 291(2025): 20240317, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38920055

ABSTRACT

An insect's wingbeat frequency is a critical determinant of its flight performance and varies by multiple orders of magnitude across Insecta. Despite potential energetic benefits for an insect that matches its wingbeat frequency to its resonant frequency, recent work has shown that moths may operate off their resonant peak. We hypothesized that across species, wingbeat frequency scales with resonance frequency to maintain favourable energetics, but with an offset in species that use frequency modulation as a means of flight control. The moth superfamily Bombycoidea is ideal for testing this hypothesis because their wingbeat frequencies vary across species by an order of magnitude, despite similar morphology and actuation. We used materials testing, high-speed videography and a model of resonant aerodynamics to determine how components of an insect's flight apparatus (stiffness, wing inertia, muscle strain and aerodynamics) vary with wingbeat frequency. We find that the resonant frequency of a moth correlates with wingbeat frequency, but resonance curve shape (described by the Weis-Fogh number) and peak location vary within the clade in a way that corresponds to frequency-dependent biomechanical demands. Our results demonstrate that a suite of adaptations in muscle, exoskeleton and wing drive variation in resonant mechanics, reflecting potential constraints on matching wingbeat and resonant frequencies.


Subject(s)
Flight, Animal , Moths , Wings, Animal , Animals , Wings, Animal/physiology , Moths/physiology , Biomechanical Phenomena
2.
Eur J Clin Nutr ; 77(8): 784-793, 2023 08.
Article in English | MEDLINE | ID: mdl-36859658

ABSTRACT

Celiac Disease (CD) continues to require a strict lifetime gluten-free diet (GFD) to maintain healthy status. Many studies have assessed the GFD nutritional adequacy in their cohorts, but an overall picture in adults and children would offer a lifetime vision to identify actionable areas of change. We aimed at assessing the nutrient intakes of adult and pediatric CD patients following a GFD diet and identifying potential areas of improvement. Systematic review was carried out across PubMed, Scopus and Scholar up to October 2022, including full-text studies that assessed the nutrient intakes of CD patients on GFD, in terms of macro- and/or micronutrients (absolute or percentage daily average). Random-effect meta-analysis and univariable meta-regression were applied to obtain pooled estimates for proportions and influencing variables on the outcome, respectively. Thirty-eight studies with a total of 2114 patients were included. Overall, the daily energy intake was 1995 (CI 1884-2106) Kcal with 47.8% (CI 45.7-49.8%) from carbohydrates, 15.5% (CI 14.8-16.2%) from proteins, and 35.8% (CI 34.5-37.0%) from fats. Of total fats, 13.2% (CI 12.4-14.0%) were saturated fats. Teenagers had the highest consumption of fats (94.9, CI 54.8-134.9 g/day), and adults presented insufficient dietary fiber intake (18.9 g, CI 16.5-21.4 g). Calcium, magnesium, and iron intakes were particularly insufficient in adolescence, whereas vitamin D was insufficient in all age groups. In conclusion, GFD may expose CD patients to high fat and low essential micronutrient intakes. Given GFD is a lifelong therapy, to prevent the occurrence of diseases (e.g. cardiovascular or bone disorders) dietary intakes need to be assessed on long-term follow-ups.


Subject(s)
Celiac Disease , Adolescent , Child , Humans , Adult , Diet, Gluten-Free , Eating , Nutritional Status , Dietary Fats
3.
J R Soc Interface ; 18(185): 20210632, 2021 12.
Article in English | MEDLINE | ID: mdl-34847789

ABSTRACT

Across insects, wing shape and size have undergone dramatic divergence even in closely related sister groups. However, we do not know how morphology changes in tandem with kinematics to support body weight within available power and how the specific force production patterns are linked to differences in behaviour. Hawkmoths and wild silkmoths are diverse sister families with divergent wing morphology. Using three-dimensional kinematics and quasi-steady aerodynamic modelling, we compare the aerodynamics and the contributions of wing shape, size and kinematics in 10 moth species. We find that wing movement also diverges between the clades and underlies two distinct strategies for flight. Hawkmoths use wing kinematics, especially high frequencies, to enhance force and wing morphologies that reduce power. Silkmoths use wing morphology to enhance force, and slow, high-amplitude wingstrokes to reduce power. Both strategies converge on similar aerodynamic power and can support similar body weight ranges. However, inter-clade within-wingstroke force profiles are quite different and linked to the hovering flight of hawkmoths and the bobbing flight of silkmoths. These two moth groups fly more like other, distantly related insects than they do each other, demonstrating the diversity of flapping flight evolution and a rich bioinspired design space for robotic flappers.


Subject(s)
Moths , Animals , Biomechanical Phenomena , Flight, Animal , Humans , Insecta , Models, Biological , Wings, Animal
4.
Proc Biol Sci ; 288(1956): 20210677, 2021 08 11.
Article in English | MEDLINE | ID: mdl-34344177

ABSTRACT

The evolution of flapping flight is linked to the prolific success of insects. Across Insecta, wing morphology diversified, strongly impacting aerodynamic performance. In the presence of ecological opportunity, discrete adaptive shifts and early bursts are two processes hypothesized to give rise to exceptional morphological diversification. Here, we use the sister-families Sphingidae and Saturniidae to answer how the evolution of aerodynamically important traits is linked to clade divergence and through what process(es) these traits evolve. Many agile Sphingidae evolved hover feeding behaviours, while adult Saturniidae lack functional mouth parts and rely on a fixed energy budget as adults. We find that Sphingidae underwent an adaptive shift in wing morphology coincident with life history and behaviour divergence, evolving small high aspect ratio wings advantageous for power reduction that can be moved at high frequencies, beneficial for flight control. By contrast, Saturniidae, which do not feed as adults, evolved large wings and morphology which surprisingly does not reduce aerodynamic power, but could contribute to their erratic flight behaviour, aiding in predator avoidance. We suggest that after the evolution of flapping flight, diversification of wing morphology can be potentiated by adaptative shifts, shaping the diversity of wing morphology across insects.


Subject(s)
Moths , Animals , Biomechanical Phenomena , Flight, Animal , Humans , Insecta , Models, Biological , Wings, Animal
5.
J Clin Med ; 10(8)2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33920785

ABSTRACT

BACKGROUND: Hepatocellular carcinoma (HCC) is a major cause of morbidity and mortality among patients with cirrhosis. The risk of HCC recurrence after a complete response among patients treated with direct-acting antivirals (DAAs) has not been fully elucidated yet. AIM: To assess the risk of HCC recurrence after DAA therapy for hepatitis C virus (HCV). METHODS: A systematic review across PubMed, Scopus and Scholar up to November 2020, including full-text studies that assessed the pattern of HCC recurrence after DAA therapy for HCV. Random-effect meta-analysis and univariable metaregression were applied to obtain pooled estimates for proportions and relative risk (RR) and variables influential for the outcome, respectively. RESULTS: Thirty-one studies with 2957 patients were included. Overall, 30% (CI, 26-34%) of the patients with a history of HCC experienced HCC recurrence after DAA therapy, at mean time intervals ranging from 4 to 21 months. This result increased when going from European studies (23%, CI, 17-28%) to US studies (34%, CI, 30-38%), to Egyptian studies (37%, CI, 27-47%), and to Asian studies (33%, CI, 27-40%). Sixty-eight percent (CI, 45-91%) of recurrent HCCs developed within 6 months of follow-up since DAA treatment, among the eight studies providing stratified data. Among the studies providing head-to-head comparisons, the HCC recurrence risk was significantly lower after DAA therapy than IFN (RR, 0.64; CI, 0.51-0.81), and after DAA therapy than no intervention (RR, 0.68; CI, 0.49-0.94). CONCLUSIONS: The recurrence of HCC after DAA is not negligible, being higher soon after the end of treatment and among non-European countries. DAA therapy seems to reduce the risk of HCC recurrence compared to an IFN regimen and no intervention.

6.
J Viral Hepat ; 28(5): 764-770, 2021 05.
Article in English | MEDLINE | ID: mdl-33586276

ABSTRACT

Global eradication of Hepatitis C Virus (HCV) is hindered by infection persistence among high-prevalence ethnic groups with insufficient access to care. Educational interventions to raise awareness on HCV have led to identification of submerged HCV cases. Our aim was to evaluate the effectiveness of a web-based platform to assess and raise the awareness of HCV among Pakistani people living in northern Italy. We created a website in Italian and Urdu language (https://survey-hcv6.webnode.it), and shared it to Pakistani people in Emilia-Romagna through Facebook groups. Participants had to fill a 15-item questionnaire on HCV infection, then watch a video on HCV, and respond to the questionnaire again. McNemar's chi-square and negative binomial multivariable regression analysis yielding incidence rate ratio (IRR) were applied. 339 subjects from 600 (57%) participated and filled the baseline questionnaire. The knowledge on HCV infection was scanty. For instance, 32% were not aware of HCV, 42% only knew that HCV infection may be long term, and only 14% knew the access to DAA treatment is provided by the Health Service. Independent predictors of worse knowledge on HCV were male gender (IRR 1.19), low instruction level (IRR 1.26), Urdu language preference (IRR 1.22), past use of intravenous drugs (1.2) and no previous HCV testing (IRR 1.36). The educational video significantly improved the knowledge on HCV among 67 subjects who refilled the questionnaire, as 97% were later aware of HCV, 99% of the long-term duration of HCV infection and 93% of the access to DAAs provided by Italian Health Service. We found a modest level of knowledge on HCV infection among Pakistani people in northern Italy, identifying predictors of worse awareness. We provided a multimedia platform which significantly improved the knowledge on HCV infection. Consequently, this approach might translate into an improved linkage to care.


Subject(s)
Hepacivirus , Hepatitis C , Antiviral Agents/therapeutic use , Ethnicity , Hepatitis C/diagnosis , Hepatitis C/epidemiology , Hepatitis C/prevention & control , Humans , Internet , Italy , Male , Multimedia , Pakistan/epidemiology , Prevalence
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