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1.
J Insect Sci ; 24(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340049

RESUMO

Insect wing surfaces have nano- and microscale features that enable multi-functionality. Leafhoppers (Hemiptera: Cicadellidae) are unique in that they produce and excrete nanoscale particles, called brochocosomes, that are spread onto the integument by the insect. Brochosomes are extra-cuticular, removable, and make the integument both superhydrophobic and anti-reflective, 2 greatly desired properties in engineering and material science fields. Adaptations like this have captured the interest of researchers looking to draw inspiration from the natural world to create novel solutions and optimize current technologies. Here, we compare brochosome size and wettability across 8 species of leafhoppers using scanning electron microscopy and microgoniometry. We demonstrate that brochosome size is variable within species and that size and wettability are both significantly impacted by species. We report the extent of variability in each case and examine the relationship between brochosome size, body length, and hydrophobicity. In discussing potential applications for brochosomes, we comment on an emerging and rapid analysis technique for evaluating small biological particles. Additionally, we discuss a few recent brochosome-inspired designs and comment on important considerations. Our work provides valuable insight on a unique system that can guide the design of functionalized materials with enhanced hydrophobic and self-cleaning properties.


Assuntos
Hemípteros , Animais , Molhabilidade , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Pele
2.
J Insect Sci ; 23(3)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37279995

RESUMO

The 2022 student debates of the Entomological Society of America (ESA) happened during the Joint Annual Meeting of the Entomological Societies of America, Canada, and British Columbia in Vancouver, BC, and addressed entomological aspects beyond research and education. The Student Debates Subcommittee of the ESA Student Affairs Committee and the participating student team members communicated for 8 months and prepared for the debates. The theme of the ESA meeting in 2022 was "Entomology as inspiration: Insects through art, science, and culture". There were 2 unbiased speakers who introduced the debate topics as well as 4 teams who debated the following 2 topics: (i) Is forensic entomology viable in criminal case investigations and court cases today? and (ii) Are insects being treated ethically in scientific research? The teams prepared for about 8 months, debated their arguments, and shared their thoughts with the audience. The teams were judged by a panel and the winners were recognized at the ESA Student Awards Session during the annual meeting.


Assuntos
Insetos , Estudantes , Animais , Humanos , Entomologia , Colúmbia Britânica , Mudanças Depois da Morte
3.
Biomacromolecules ; 24(1): 190-200, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36516996

RESUMO

Insects known as leafhoppers (Hemiptera: Cicadellidae) produce hierarchically structured nanoparticles known as brochosomes that are exuded and applied to the insect cuticle, thereby providing camouflage and anti-wetting properties to aid insect survival. Although the physical properties of brochosomes are thought to depend on the leafhopper species, the structure-function relationships governing brochosome behavior are not fully understood. Brochosomes have complex hierarchical structures and morphological heterogeneity across species, due to which a multimodal characterization approach is required to effectively elucidate their nanoscale structure and properties. In this work, we study the structural and mechanical properties of brochosomes using a combination of atomic force microscopy (AFM), electron microscopy (EM), electron tomography, and machine learning (ML)-based quantification of large and complex scanning electron microscopy (SEM) image data sets. This suite of techniques allows for the characterization of internal and external brochosome structures, and ML-based image analysis methods of large data sets reveal correlations in the structure across several leafhopper species. Our results show that brochosomes are relatively rigid hollow spheres with characteristic dimensions and morphologies that depend on leafhopper species. Nanomechanical mapping AFM is used to determine a characteristic compression modulus for brochosomes on the order of 1-3 GPa, which is consistent with crystalline proteins. Overall, this work provides an improved understanding of the structural and mechanical properties of leafhopper brochosomes using a new set of ML-based image classification tools that can be broadly applied to nanostructured biological materials.


Assuntos
Hemípteros , Nanoestruturas , Animais , Hemípteros/anatomia & histologia , Hemípteros/química , Tomografia com Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Molhabilidade
4.
ACS Nano ; 16(8): 12910-12921, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35960260

RESUMO

Particulate transport from surfaces governs a variety of phenomena including fungal spore dispersal, bioaerosol transmission, and self-cleaning. Here, we report a previously unidentified mechanism governing passive particulate removal from superhydrophobic surfaces, where a particle coalescing with a water droplet (∼10 to ∼100 µm) spontaneously launches. Compared to previously discovered coalescence-induced binary droplet jumping, the reported mechanism represents a more general capillary-inertial dominated transport mode coupled with particle/droplet properties and is typically mediated by rotation in addition to translation. Through wetting and momentum analyses, we show that transport physics depends on particle/droplet density, size, and wettability. The observed mechanism presents a simple and passive pathway to achieve self-cleaning on both artificial as well as biological materials as confirmed here with experiments conducted on butterfly wings, cicada wings, and clover leaves. Our findings provide insights into particle-droplet interaction and spontaneous particulate transport, which may facilitate the development of functional surfaces for medical, optical, thermal, and energy applications.


Assuntos
Água , Asas de Animais , Animais , Interações Hidrofóbicas e Hidrofílicas , Molhabilidade , Água/química , Folhas de Planta
5.
Insects ; 14(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36661970

RESUMO

Insects demonstrate a wide diversity of microscopic cuticular and extra-cuticular features. These features often produce multifunctional surfaces which are greatly desired in engineering and material science fields. Among these functionalities, hydrophobicity is of particular interest and has gained recent attention as it often results in other properties such as self-cleaning, anti-biofouling, and anti-corrosion. We reviewed the historical and contemporary scientific literature to create an extensive review of known hydrophobic and superhydrophobic structures in insects. We found that numerous insects across at least fourteen taxonomic orders possess a wide variety of cuticular surface chemicals and physical structures that promote hydrophobicity. We discuss a few bioinspired design examples of how insects have already inspired new technologies. Moving forward, the use of a bioinspiration framework will help us gain insight into how and why these systems work in nature. Undoubtedly, our fundamental understanding of the physical and chemical principles that result in functional insect surfaces will continue to facilitate the design and production of novel materials.

6.
Open Access Maced J Med Sci ; 4(3): 337-341, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27703552

RESUMO

AIM: This study evaluated the curative potential of Crinum giganteum in the treatment of schizophrenia using an NMDA-receptor antagonist-induced schizophrenic Wistar rat model. METHODS: Twenty-five adult Wistar rats of both sexes of average weights 180 g were divided into two groups: control and schizophrenic rat models. The controls received 0.1 ml of 0. 9% saline, while schizophrenia was induced in models using 25 mg/kg of ketamine hydrochloride (i.p.) for 7 days. On the 8 day models were divided into group's k1, k2, k3 and k4 of 5 rats each. K1 and the controls were sacrificed then, groups k2 and k3 were treated with 5 mg/kg and 10 mg/kg aqueous leaf extract of Crinum giganteum while, k4 (standard) received 25 mg/kg of chlorpromazine orally for 28 days. Amygdala were harvested, processed and stained with Haematoxylin and Eosin (H &E) stain, Neuron-specific enolase (NSE) marker was also used to monitor the curative effect on the amygdala. RESULTS: Degenerative changes and increased NSE immunoreactivity were observed in the untreated models. Extract-treated models showed normal amygdala and negative NSE immunoreactivity while chlorpromazine treated models revealed decreased NSE immunoreactivity. CONCLUSION: Crinum giganteum extracts exhibits better curative effect than the standard antipsychotic agent.

7.
J Fam Pract ; 60(11 Suppl): S6-11, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22336928

RESUMO

Specialized diabetes care (SDC) centers utilize a multidisciplinary diabetes team to provide patients with highly individualized care. Patients at SDC centers receive their integrated diabetes care in one place--the "one-stop" approach. The components of the SDC center model are: medical care; individualized diabetes education; nutrition; exercise and lifestyle coaching; counseling; monitoring of drug effects. This model results in improved patient outcomes and reduced overall costs.


Assuntos
Atenção à Saúde , Gerenciamento Clínico , Conduta do Tratamento Medicamentoso , Modelos Organizacionais , Equipe de Assistência ao Paciente/organização & administração , Autocuidado/métodos , Doença Crônica/psicologia , Redes Comunitárias/organização & administração , Comportamento Cooperativo , Atenção à Saúde/organização & administração , Atenção à Saúde/tendências , Diabetes Mellitus/terapia , Pessoal de Saúde/psicologia , Pessoal de Saúde/normas , Humanos , Assistência de Longa Duração/métodos , Conduta do Tratamento Medicamentoso/normas , Conduta do Tratamento Medicamentoso/tendências , Modelos Educacionais , Educação de Pacientes como Assunto/organização & administração , Participação do Paciente , Apoio Social
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