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1.
Sci Adv ; 10(17): eadl5255, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38657058

RESUMO

Sex-limited polymorphism has evolved in many species including our own. Yet, we lack a detailed understanding of the underlying genetic variation and evolutionary processes at work. The brood parasitic common cuckoo (Cuculus canorus) is a prime example of female-limited color polymorphism, where adult males are monochromatic gray and females exhibit either gray or rufous plumage. This polymorphism has been hypothesized to be governed by negative frequency-dependent selection whereby the rarer female morph is protected against harassment by males or from mobbing by parasitized host species. Here, we show that female plumage dichromatism maps to the female-restricted genome. We further demonstrate that, consistent with balancing selection, ancestry of the rufous phenotype is shared with the likewise female dichromatic sister species, the oriental cuckoo (Cuculus optatus). This study shows that sex-specific polymorphism in trait variation can be resolved by genetic variation residing on a sex-limited chromosome and be maintained across species boundaries.


Assuntos
Polimorfismo Genético , Animais , Feminino , Masculino , Aves/genética , Fenótipo , Evolução Biológica , Pigmentação/genética , Caracteres Sexuais , Evolução Molecular
2.
JMIR Res Protoc ; 12: e47874, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999949

RESUMO

BACKGROUND: The circular economy reshapes the linear "take, make, and dispose" approach and evolves around minimizing waste and recapturing resources in a closed-loop system. The health sector accounts for 4.6% of global greenhouse gas emissions and has, over the decades, been built to rely on single-use devices and deal with high volumes of medical waste. With the increase in the adoption of digital health solutions in the health care industry, leading the industry into a new paradigm of how we provide health care, a focus must be put on the amount of waste that will follow. Digital health solutions will shape health care through the use of technology and lead to improved patient care, but they will also make medical waste more complex to deal with due to the e-waste component. Therefore, a transformation of the health care industry to a circular economy is a crucial cornerstone in decreasing the impact on the environment. OBJECTIVE: This study aims to address the lack of direction in the current literature on circular business models. It will consider micro, meso, and macro factors that would impact the operational validity of circular models using the digital health solutions ePaper label (medical packaging), smart wearable sensor (health monitoring devices), smart pill box (medication management), and endo-cutter (surgical equipment) as examples. METHODS: The study will systematically perform a scoping review through a database and snowball search. We will analyze and classify the studies from a predetermined set of categories and then summarize them into an evidence map. Based on the review, the study will develop a 2D framework for businesses to follow or for future research to take a standpoint from. RESULTS: Preliminarily, the review has analyzed 26 studies in total. The results are close to equally distributed among the micro (8/26, 31%), meso (10/26, 38%), and macro (8/26, 31%) levels. Circular economy studies emphasize several circular practices such as recycling (17/26, 65%), reusing (18/26, 69%), reducing (15/26, 58%), and remanufacturing (8/26, 31%). The value proposition in the examined business model is mostly dominated by stand-alone products (18/26, 69%) compared to product as a service (7/26, 27%), involving stakeholders such as health care professionals or hospitals (20/26, 77%), manufacturers (11/26, 42%), and consumers (9/26, 35%). All studies encompass societal (12/26, 46%), economic (23/26, 88%), and environmental (24/26, 92%) viewpoints. CONCLUSIONS: The study argues that each digital health solution would have to be accessed individually to find the optimal business model to follow. This is due to their differing life cycles and complexity. The manufacturer will need a layered value proposition, implementing several business models dependent on their respective product portfolios. The need to incorporate several business models implies an ecosystem perspective that is relevant to consider. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47874.

3.
Front Neurol ; 13: 927481, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016543

RESUMO

Visual dysfunction is a recognized early symptom of Parkinson's disease (PD) that partly scales motor symptoms, yet its background is heterogeneous. With additional deficits in visuospatial attention, the two systems are hard to disentangle and it is not known whether impaired functional connectivity in the visual cortex is translative in nature or disrupted attentional modulation also contributes. In this study, we investigate functional connectivity modulation during a visuospatial attention task in patients with PD. In total, 15 PD and 16 age-matched healthy controls performed a visuospatial attention task while undergoing fMRI, in addition to a resting-state fMRI scan. Tensorial independent component analysis was used to investigate task-related network activity patterns. Independently, an atlas-based connectivity modulation analysis was performed using the task potency method. Spearman's rank correlation was calculated between task-related network expression, connectivity modulation, and clinical characteristics. Task-related networks including mostly visual, parietal, and prefrontal cortices were expressed to a significantly lesser degree in patients with PD (p < 0.027). Resting-state functional connectivity did not differ between the healthy and diseased cohorts. Connectivity between the precuneus and ventromedial prefrontal cortex was modulated to a higher degree in patients with PD (p < 0.004), while connections between the posterior parietal cortex and primary visual cortex, and also the superior frontal gyrus and opercular cortex were modulated to a lesser degree (p < 0.001 and p < 0.011). Task-related network expression and superior frontal gyrus-opercular cortex connectivity modulation were significantly associated with UPDRSIII motor scores and the Hoehn-Yahr stages (R = -0.72, p < 0.006 and R = -0.90, p < 0.001; R = -0.68, p < 0.01 and R = -0.71, p < 0.007). Task-related networks function differently in patients with PD in association with motor symptoms, whereas impaired modulation of visual and default-mode network connectivity was not correlated with motor function.

4.
Ecol Evol ; 12(8): e9177, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35979521

RESUMO

The mechanistic link between avian oxidative physiology and plumage coloration has attracted considerable attention in past decades. Hence, multiple proximal hypotheses were proposed to explain how oxidative state might covary with the production of melanin and carotenoid pigments. Some hypotheses underscore that these pigments (or their precursors, e.g., glutathione) have antioxidant capacities or function as molecules storing the toxic excess of intracellular compounds, while others highlight that these pigments can act as pro-oxidants under specific conditions. Most studies addressing these associations are at the intraspecific level, while phylogenetic comparative studies are still scarce, though needed to assess the generality of these associations. Here, we tested whether plumage and bare part coloration were related to oxidative physiology at an interspecific level by measuring five oxidative physiology markers (three nonenzymatic antioxidants and two markers of lipid peroxidative damage) in 1387 individuals of 104 European bird species sampled during the breeding season, and by scoring plumage eumelanin, pheomelanin, and carotenoid content for each sex and species. Only the plasma level of reactive oxygen metabolites was related to melanin coloration, being positively associated with eumelanin score and negatively with pheomelanin score. Thus, our results do not support the role of antioxidant glutathione in driving variation in melanin synthesis across species. Furthermore, the carotenoid scores of feathers and bare parts were unrelated to the measured oxidative physiology parameters, further suggesting that the marked differences in pigmentation across birds does not influence their oxidative state.

5.
Brain Topogr ; 35(2): 268-275, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34807323

RESUMO

Laterality patterns of resting state networks (RSN) change in various neuropsychiatric conditions. Multiple sclerosis (MS) causes neuro-cognitive symptoms involving dysfunctional large-scale brain networks. Yet, whether healthy laterality patterns of RSNs are maintained in MS and whether altered laterality patterns explain disease symptoms has not been explicitly investigated. We analysed functional MRI and diffusion tensor imaging data from 24 relapsing-remitting MS patients and 25 healthy participants. We performed group-level independent component analysis and used dual regression to estimate individual versions of well-established RSNs. Voxelwise laterality indices were calculated for each RSN. Group differences were assessed via a general linear model-based approach. The relationship between functional laterality and white matter microstructural asymmetry was assessed using Tract-Based Spatial Statistics. Spearman's correlation was calculated between laterality indices and Brief International Cognitive Assessment for Multiple Sclerosis scores. Functional laterality of the dorsal attention network showed a significant leftward shift in the MS group in the posterior intraparietal sulcus (p < 0.033). Default-mode network laterality showed a significant leftward shift in the MS group in the angular gyrus (p < 0.005). Diminished dorsal attention network laterality was associated with increased fractional anisotropy asymmetry in the superior longitudinal fasciculus (p < 0.02). In the default-mode network, leftward laterality of the angular gyrus was associated with higher BVMT-R scores (R = - 0.52, p < 0.023). Our results confirm previous descriptions of RSN dysfunction in relapsing-remitting MS and show that altered functional connectivity lateralisation patterns of RSNs might contibute to cognitive performance and structural remodellation even in patients with mild clinical symptoms.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Substância Branca , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
6.
Ecol Evol ; 11(13): 8420-8423, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34257907

RESUMO

Multiple parasitism in obligate avian brood parasites occurs when several brood parasitic females lay their eggs in the nest of the same host. While multiple parasitism is common in the highly social, nonevicting cowbird species (Molothrus sp.), in which multiple parasitic nestlings can be raised simultaneously by the same hosts, it is less common in the case of cuckoo species (Cuculus sp.). The first cuckoo nestling to hatch from the egg evicts all nestmates; therefore, it is costly for cuckoo females to lay eggs in already parasitized nests. However, this can occur in sites with very high parasitism rates, and it can even increase the breeding success of the brood parasites, as the presence of multiple parasitic eggs in the nest of the host decreases rejection rates. Here, we present a case of a quintuple brood parasitism of a great reed warbler (Acrocephalus arundinaceus) nest, an extreme form of multiple brood parasitism.

7.
Naturwissenschaften ; 107(4): 28, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32564143

RESUMO

Female-only colour polymorphism is rare in birds, but occurs in brood parasitic cuckoos (Cuculidae). Obligate brood parasites leave incubation and parental care to other species (hosts), so female-female interactions can play a role in how parasites guard critical resources (host nests) within their laying areas. The plumage of adult female common cuckoos (Cuculus canorus) is either rufous (typically rare) or grey (common), whereas adult male conspecifics are monochromatic (grey). In previous studies, hosts and conspecific males responded with less intensity toward the rare female morph in support of a negative frequency-dependent benefit of female plumage polychromatism. Here, we assessed responses of both conspecific females and males to vocal playbacks of female calls, coupled with one of two 3D models of the different morphs of female cuckoos. At our study population, the rufous female morph was as common as the grey morph; therefore, we predicted similarly high rates of conspecific responses in both treatments. Both female and male cuckoos responded to playbacks acoustically, which demonstrated the primary role of acoustic communication in social interactions amongst cuckoos. Following this, some cuckoos flew closer to the models to inspect them visually. As predicted, no significant differences were detected between the live cuckoos' responses toward the two colour morphs in this population. We conclude that dichromatism in female cuckoos evolved to serve one or more functions other than conspecific signalling.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Aves/fisiologia , Pigmentação/fisiologia , Animais , Feminino , Masculino , Aves Canoras/parasitologia , Vocalização Animal
8.
Sci Rep ; 9(1): 18563, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811179

RESUMO

It is well known that avian brood parasites lay their eggs in the nests of other bird species, called hosts. It remains less clear, however, just how parasites are able to recognize their hosts and identify the exact location of the appropriate nests to lay their eggs in. While previous studies attributed high importance to visual signals in finding the hosts' nests (e.g. nest building activity or the distance and direct sight of the nest from vantage points used by the brood parasites), the role of host acoustic signals during the nest searching stage has been largely neglected. We present experimental evidence that both female and male common cuckoos Cuculus canorus pay attention to their host's, the great reed warbler's Acrocephalus arundinaceus alarm calls, relative to the calls of an unparasitized species used as controls. Parallel to this, we found no difference between the visibility of parasitized and unparasitized nests during drone flights, but great reed warblers that alarmed more frequently experienced higher rates of parasitism. We conclude that alarm calls might be advantageous for the hosts when used against enemies or for alerting conspecifics, but can act in a detrimental manner by providing important nest location cues for eavesdropping brood parasites. Our results suggest that host alarm calls may constitute a suitable trait on which cuckoo nestlings can imprint on to recognize their primary host species later in life. Our study contributes to the growing body of knowledge regarding the context-dependency of animal signals, by providing a novel example of a beneficial acoustic trait intercepted by a heterospecific and used against the emitter.


Assuntos
Atenção/fisiologia , Comportamento de Nidação/fisiologia , Passeriformes/fisiologia , Vocalização Animal/fisiologia , Animais , Feminino , Masculino , Especificidade da Espécie
9.
Beilstein J Org Chem ; 14: 2589-2596, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410620

RESUMO

Multistep syntheses of novel 17ß-pyrazol-5'-ones in the Δ5-androstane series were efficiently carried out from pregnenolone acetate. A steroidal 17-carboxylic acid was first synthesized as a norpregnene precursor by the bromoform reaction and subsequent acetylation. Its CDI-activated acylimidazole derivative was then converted to a ß-ketoester containing a two carbon atom-elongated side chain than that of the starting material. A Knorr cyclization of the bifunctional 1,3-dicarbonyl compound with hydrazine and its monosubstituted derivatives in AcOH under microwave heating conditions led to the regioselective formation of 17-exo-heterocycles in good to excellent yields. The suppression of an acid-catalyzed thermal decarboxylation of the ß-ketoester and thus a significant improvement in the yield of the desired heterocyclic products could be achieved by the preliminary liberation of the arylhydrazines from their hydrochloride salts in EtOH in the presence of NaOAc. The reaction rates were found to depend on the electronic character of the substituent present in the phenylhydrazine applied. The antiproliferative activities of the structurally related steroidal pyrazol-5'-ones and their deacetylated analogs were screened on three human adherent breast cancer cell lines (MCF7, T47D and MDA-MB-231): the microculture tetrazolium assay revealed that some of the presented derivatives exerted cell growth inhibitory effects on some of these cell lines comparable to those of the reference compound, cisplatin.

10.
Behav Processes ; 157: 685-690, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29559339

RESUMO

Common cuckoos (Cuculus canorus) are best known for their simple two-note calls ("cu-coo"), which are uttered only by males during the breeding season. A previous playback study revealed that territorial males were more tolerant toward playbacks of the calls of familiar, neighbouring individuals than toward unfamiliar, stranger simulated intruders, exhibiting the classical "dear-enemy" phenomenon. Here we experimentally assessed whether the acoustic cues for familiarity recognition are encoded in the first and/or second note of these simple calls. To do so, we played mixed sound files to radio-tagged cuckoos, where the first part of the two-note calls was taken from strangers and the second part from neighbours, or vice versa. As controls, we used behavioural data from two-note neighbour and two-note stranger call playbacks. Cuckoos responded consistently to the two types of mixed sound files. When either the first or second note of the call was taken from a stranger and the other note from a neighbour, they responded to these sound files similarly to two-note playbacks of strangers: they approached the speaker of the playbacks more closely and the calling response-latency to playbacks was longer than to familiar controls. These findings point to the importance of both notes in familiarity recognition. We conclude that familiarity recognition in male common cuckoos needs the complete structure of the two-note cuckoo call, which is characteristic for this species.


Assuntos
Aves/fisiologia , Reconhecimento Psicológico/fisiologia , Vocalização Animal/fisiologia , Acústica , Animais , Som , Territorialidade
11.
PLoS One ; 7(7): e40651, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808221

RESUMO

BACKGROUND: The trade-off between current and residual reproductive values is central to life history theory, although the possible mechanisms underlying this trade-off are largely unknown. The 'molt constraint' hypothesis suggests that molt and plumage functionality are compromised by the preceding breeding event, yet this candidate mechanism remains insufficiently explored. METHODOLOGY/PRINCIPAL FINDINGS: The seasonal change in photoperiod was manipulated to accelerate the molt rate. This treatment simulates the case of naturally late-breeding birds. House sparrows Passer domesticus experiencing accelerated molt developed shorter flight feathers with more fault bars and body feathers with supposedly lower insulation capacity (i.e. shorter, smaller, with a higher barbule density and fewer plumulaceous barbs). However, the wing, tail and primary feather lengths were shorter in fast-molting birds if they had an inferior body condition, which has been largely overlooked in previous studies. The rachis width of flight feathers was not affected by the treatment, but it was still condition-dependent. CONCLUSIONS/SIGNIFICANCE: This study shows that sedentary birds might face evolutionary costs because of the molt rate-feather quality conflict. This is the first study to experimentally demonstrate that (1) molt rate affects several aspects of body feathers as well as flight feathers and (2) the costly effects of rapid molt are condition-specific. We conclude that molt rate and its association with feather quality might be a major mediator of life history trade-offs. Our findings also suggest a novel advantage of early breeding, i.e. the facilitation of slower molt and the condition-dependent regulation of feather growth.


Assuntos
Comportamento Animal/fisiologia , Plumas/anatomia & histologia , Plumas/crescimento & desenvolvimento , Muda/fisiologia , Fotoperíodo , Pardais/crescimento & desenvolvimento , Animais , Voo Animal/fisiologia , Masculino , Modelos Biológicos , Pardais/anatomia & histologia , Cauda/anatomia & histologia
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