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In this work, we study thermalization between two bodies separated by a vacuum gap by coupling the non-Fourier behavior of the materials with the radiative heat transfer in the near-field. Unlike the diffusion-type temperature profile, in non-Fourier materials, the temperature behaves as a wave, changing the thermalization process. Due to the temperature profile induced by the coupling with conduction, we show that the radiative heat flux exchanged between the two bodies differs from the Fourier case and exhibits transient temperature effects at the onset of the thermalization process. These results have important implications in nanoscale thermal management, near-field solid-state cooling, and nanoscale energy conversion. [ABSTRACT FROM AUTHOR]

The present study examines the impact of acidic and basic pH on the optical, morphological, and structural characteristics of TiO2 sol–gel thin films that are deposited using the dip-coating technique on glass substrates. All of the samples are polycrystalline and have anatase structures with preference orientation along the (101) direction, according to X-ray diffraction (XRD) and Raman spectroscopy (RS). It is observed that, for both basic and acidic pH values, crystallite size decreases as sol pH rises. All of the films' surfaces were smooth and had a uniform grain distribution, according to atomic force microscopy (AFM). The pH of the sol has an impact on the surface roughness. All films had a higher degree of transparency, according to UV-visible spectroscopy. The refractive index and the direct and indirect band gaps are two essential optical properties of thin films that are significantly influenced by the pH of the deposition medium. Measurements of photoluminescence (PL) showed a strong violet-blue emission band, the intensity of which is highly dependent on the sol's pH. In acidic media, PL decreases with increasing pH. However, in a basic environment, the PL rises sharply as the pH increases from 10 to 11 and then decreases for higher pH values. In particular, compared to the other samples, the emission intensity from the film deposited at a pH value of 10 is noticeably lower and displays unique spectral signatures. Highlights: The effects of acidic and basic pH on the structural, morphological, and optical properties of TiO2 sol–gel thin films were investigated. XRD analyses show that crystallite size decreases with increasing pH in both acidic and basic sols. Optical analysis demonstrates that TiO2 thin films deposited at acidic pH values have greater transparency than those deposited at basic pH values. Photoluminescence measurements revealed a strong correlation between sample emission and pH. The film deposited at pH 10 has significantly lower emission intensity and a distinct spectral signature than the other samples. [ABSTRACT FROM AUTHOR]

In this study we report on the preparation of Ni (II), Pd (II), Co (II), and Cu (II) complexes with H2cdsalen (methyl-2{N-[2-(2'-hydroxyphenyl)methylidenenitrilo]ethyl}amino-1- cyclopentenedithiocarboxylate)salicylaldehyde. The products were characterized using 1D NMR (¹H and [sup.13]C) and 2D NMR (COSY, NOESY, and ROESY) techniques. The conformational studies of the complexes with Ni and Pd in solution have been performed with help of the nuclear Overhauser effect (NOE) and 2D ROESY experiments. Key words: ROESY, conformational, H2cdsalen. On a effectue la preparation de complexes du Ni (II), Pd (II), Co (II) et Cu (II) avec le (methyl-2-{N-[2-(2'-hydroxyphenyl)methylidenenitrilo]ethyl}amino-2- cyclopentenedithiocarboxylate)salicaldehyde, H2cdsalen. Les produits ont ete caracterises par des techniques de RMN 1D du ¹H et du [sup.13]C et de RMN 2D << COSY >>, << NOESY >>, << ROESY >>. On a realise des etudes conformationnelles des complexes du Ni et du Pd en solution en faisant appel a des mesures de l'effet Overhauser nucleaire (EON) et du << ROESY >> 2D. Mots-cles : ROESY, conformationnelle, H2cdsalen. [Traduit par la Redaction], Introduction The coordination compounds of transition metals have had great impact on numerous branches of science, from catalysis, (1-5) medicine, (6-10) or analytical chemistry (11-14) to the design and construction [...]

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Phytoplankton, especially the nanoplankton fraction, and its possible relationships with the hydrographic conditions in the southern Gulf of Mexico were studied during an oceanographic cruise in April 2000. Hydrographic data and phytoplankton were analyzed. Phytoplankton species composition showed heterogeneity among stations. A total of 180 species were found: 114 diatoms, 32 dinoflagellates, 32 coccolithophores, and 2 silicoflagellates. Diversity indices were variable (0.96-5.12 bits ind-1). Phytoplankton was numerically dominated by coccolithophores or nanoplanktonic diatoms. Cell abundance was low to moderately high, ranging from 5.3 × 103 to 1.4 × 105 cells L-1. The most abundant, dominant species were nanoplanktonic forms: two coccolithophores, Emiliania huxleyi and Gephyrocapsa oceanica; the pennate diatoms Nitzschia bicapitata, N. bifurcata and N. leehyi; and centric diatoms of the genus Thalassiosira. The high subsurface abundance of coccolithophores at two stations was related to a thermal front in the Grijalva-Usumacinta river system. [ABSTRACT FROM AUTHOR]

An abstract of the article "Free-Living Unarmored Marine Dinoflagellates From the Southern Gulf of Mexico and the Mexican Pacific," by S. Escobar-Morales and D. U. Hernández-Becerril, is presented.

Eddies and fronts created by geostrophic balance between counter-rotating currents are hydrodynamic processes that concentrate or dilute plankton and suspended material by physical processes of accumulation, retention, or dispersion. Over Campeche Canyon, in the southern Gulf of Mexico, observations revealed an anticyclonic eddy, a cyclonic current off the continental shelf, and an associated thermal front in their common boundary. Along this front there was high Trichodesmium spp. occurrence. Three water masses were found in the upper 120 m layer: Caribbean Tropical Surface Water (CTSW), Caribbean Subtropical Underwater (CSUW), and Gulf Common Water (GCW). The frontal zone between the warm core and cyclonic circulation was observed below the hot summertime mixed layer. The presence of Trichodesmium spp. was associated with the front, indicating its influence on the distribution of this diazotrophic cyanobacterium that enters the Campeche Canyon region via modified CTSW. The associated phytoplankton was dominated by tropical oceanic species of diatoms and dinoflagellates, especially species of Ceratium. [ABSTRACT FROM AUTHOR]

Over the last 20 years, the incidence of vertical HIV transmission has decreased from 25%-42% to less than 1%. Although there are no signs of infection, the health of HIV-exposed uninfected (HEU) infants is notoriously affected during the first months of life, with opportunistic infections being the most common disease. Some studies have reported effects on the vertical transfer of antibodies, but little is known about the subclass distribution of these antibodies. We proposed to evaluate the total IgG concentration and its subclasses in HIV+ mothers and HEU pairs and to determine which maternal factors condition their levels. In this study, plasma from 69 HEU newborns, their mothers, and 71 control pairs was quantified via immunoassays for each IgG isotype. Furthermore, we followed the antibody profile of HEUs throughout the first year of life. We showed that mothers present an antibody profile characterized by high concentrations of IgG1 and IgG3 but reduced IgG2, and HEU infants are born with an IgG subclass profile similar to that of their maternal pair. Interestingly, this passively transferred profile could remain influenced even during their own antibody production in HEU infants, depending on maternal conditions such as CD4+ T-cell counts and maternal antiretroviral treatment. Our findings indicate that HEU infants exhibit an altered IgG subclass profile influenced by maternal factors, potentially contributing to their increased susceptibility to infections., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2024 Rodrigo T. Camacho-Pacheco et al.)

Background: Developing effective vaccines against SARS-CoV-2 that consider manufacturing limitations, equitable access, and acceptance is necessary for developing platforms to produce antigens that can be efficiently presented for generating neutralizing antibodies and as a model for new vaccines., Results: This work presents the development of an applicable technology through the oral administration of the SARS-CoV-2 RBD antigen fused with a peptide to improve its antigenic presentation. We focused on the development and production of the recombinant receptor binding domain (RBD) produced in E. coli modified with the addition of amino acids extension designed to improve antigen presentation. The production was carried out in shake flask and bioreactor cultures, obtaining around 200 mg/L of the antigen. The peptide-fused RBD and peptide-free RBD proteins were characterized and compared using SDS-PAGE gel, high-performance chromatography, and circular dichroism. The peptide-fused RBD was formulated in an oil-in-water emulsion for oral mice immunization. The peptide-fused RBD, compared to RBD, induced robust IgG production in mice, capable of recognizing the recombinant RBD in Enzyme-linked immunosorbent assays. In addition, the peptide-fused RBD generated neutralizing antibodies in the sera of the dosed mice. The formulation showed no reactive episodes and no changes in temperature or vomiting., Conclusions: Our study demonstrated the effectiveness of the designed peptide added to the RBD to improve antigen immunostimulation by oral administration., (© 2024. The Author(s).)

Ketemines represent an interesting class of organic intermediates that has undergone a regrowth as a consequence of recent extensions of copper catalyzed azide alkyne cycloaddition (Cu- AAC) to other synthetic fields. This review summarizes the most recent generation methods of ketimines from CuAAC reaction, highlighting chemical properties focused on the synthesis of cyclic compounds, among others, affording a general outlook towards the development of new biologically active compounds., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)