Publications by authors named "Carlos Alberto Rodrigues Costa"

This study investigates the nanoscale surface morphology of Anopheles darlingi and Anopheles aquasalis mosquito wings using Atomic Force Microscopy (AFM) and fractal analysis. High-resolution 3D AFM imaging revealed pronounced inter- and intra-species differences, with the ventral surface of An. darlingi (V-Ad) exhibiting the greatest roughness (Sq = 45.

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Deciphering the nanoscale architecture of mosquito wings is crucial for understanding species-specific flight adaptations and vectorial behaviors. In this study, we present a comprehensive quantitative analysis of the wing surface morphology of Anopheles darlingi and Anopheles aquasalis. By integrating high-resolution microscopy with Minkowski functionals and multifractal formalism, we reveal pronounced interspecific and dorso-ventral asymmetries in mosquito wing surfaces at both micro- and nanoscales.

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Unstrained GaAs quantum dots are promising candidates for quantum information devices due to their optical properties, but their electronic properties have remained relatively unexplored until now. In this work, we systematically investigate the electronic structure and natural charging of GaAs quantum dots at room temperature using Kelvin probe force microscopy (KPFM). We observe a clear electrical signal from these structures demonstrating a lower surface potential in the middle of the dot.

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Increasing interest in nanoparticles of technological application has been improving their fabrication processes. The encapsulation of essential oils as bioactive compounds has proved to be an excellent alternative to the use of less environment friendly compounds. However, the difficulty of identifying their constitution and interaction with carrier agents have aroused scientific interest and a problem to overcome.

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The increasing need for point-of-care diagnosis has sparked the development of label-free sensing platforms, some of which are based on impedance measurements with biological cells. Here, interdigitated electrodes were functionalized with layer-by-layer (LbL) films of hyaluronan (HA) and chitosan (CHI) to detect prostatic tumor cells (PC3 line). The deposition of LbL films was confirmed with atomic force microscopy and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), which featured the vibrational modes of the HA top layer capable of interacting specifically with glycoprotein CD44 receptors overexpressed in tumor cells.

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Surface-Mounted Metal-Organic Frameworks (SURMOFs) are promising materials with a wide range of applications and increasing interest in different technological fields. The use of SURMOFs as both the active and passive tail in electronic devices is one of the most exciting possibilities for such a hybrid material. In such a context, the adhesion, roughness, and crystallinity control of SURMOF thin films are challenging and have limited their application in new functional electronic devices.

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Dry films formed by surfactant-stabilized, peroxide-initiated styrene-butyl acrylate latex were examined by atomic and electric force microscopy (AFM and EFM). The effects of latex serum components on the films were observed by subjecting the latex to extensive dialysis prior to film formation, and comparing the results to as-prepared latex. The films formed with the dialyzed latex are smoother (as evidenced by roughness and fractal dimension measurements) than the films from the as-prepared latex, but they display large electric force gradients between neighboring domains.

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The surface of a poly(styrene-hydroxyethylmethacrylate), macrocrystalline film was observed by atomic force microscopy in the contact mode, before and during film immersion in water. The swelling effect on film morphology is strongly dependent on the quality of the macrocrystalline surface: film integrity is preserved or concerted many-particle displacement is observed in well-organized areas with few defects, but extensive particle displacement is observed in highly defective areas. The lateral particle dimensions increase by ca.

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