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1.
Plant Physiol Biochem ; 214: 108889, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38954945

RESUMO

Abscisic acid (ABA) is crucial for plant water deficit (WD) acclimation, but how the interplay between ABA and guard cell (GC) metabolism aids plant WD acclimation remains unclear. Here, we investigated how ABA regulates GC metabolism and how this contributes to plant WD acclimation using tomato wild type (WT) and the ABA-deficient sitiens mutant. These genotypes were characterized at physiological, metabolic, and transcriptional levels under recurring WD periods and were used to perform a13C-glucose labelling experiment using isolated guard cells following exogenously applied ABA. ABA deficiency altered the level of sugars and organic acids in GCs in both irrigated and WD plants and the dynamic of accumulation/degradation of these compounds in GCs during the dark-to-light transition. WD-induced metabolic changes were more pronounced in sitiens than WT GCs. Results from the 13C-labelling experiment indicate that ABA is required for the glycolytic fluxes toward malate and acts as a negative regulator of a putative sucrose substrate cycle. The expression of key ABA-biosynthetic genes was higher in WT than in sitiens GCs after two cycles of WD. Additionally, the intrinsic leaf water use efficiency increased only in WT after the second WD cycle, compared to sitiens. Our results highlight that ABA deficiency disrupts the homeostasis of GC primary metabolism and the WD memory, negatively affecting plant WD acclimation. Our study demonstrates which metabolic pathways are activated by WD and/or regulated by ABA in GCs, which improves our understanding of plant WD acclimation, with clear consequences for plant metabolic engineering in the future.

2.
Purinergic Signal ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031243

RESUMO

Cancer cases have increased worldwide. Cutaneous melanoma (CM), a highly metastatic skin cancer, largely contributes to global statistical cancer death data. Research has shown that rosmarinic acid (RA) is a promising phenolic compound with antineoplastic properties. Thus, we investigated the effects of RA on apoptosis-inducing in melanoma cells, purinergic signaling modulation, and cytokine levels. We treated SK-MEL-28 cells for 24 h with different concentrations of RA and assessed the apoptosis, CD39, CD73, and A2A expression, and cytokine levels. We found RA-induced apoptosis in melanoma cells. Regarding the purinergic system, we verified that RA downregulated the expression of CD73 and A2A, specially at high concentrations of treatment. Additionally, RA increased IL-6, IL-4, IL-10, IFN-γ, and TNF-α levels. Our in vitro results confirm RA's potential to be used to induce melanoma cell apoptosis, having CD73 and A2A as targets when reversion of immune suppression is desired. Further studies in animal models and clinical trials focusing on RA's modulation of purinergic signaling in melanoma are required.

3.
Plant Biol (Stuttg) ; 26(5): 868-877, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38967326

RESUMO

Detecting changes in the phenological responses of herbaceous species as a function of predicted climate change is important for forecasting future scenarios for the functioning of dry tropical forests, especially when predicting an increase in the frequency and intensity of extreme droughts. Because of the sensitivity of plants to water availability, our study hypothesizes that if years become drier or wetter, herbaceous plants will synchronously change the onset, duration, and intensity of their vegetative phenophases. We used a historical series of 60 years of precipitation observations for the Caatinga vegetation to define daily average of precipitation for rainy (Twet), median (Tcontrol), and dry (Tdry) years. We simulated past average daily rainfall (Twet, Tcontrol, and Tdry) while growing two herbaceous perennials and two herbaceous annuals. We monitored plant growth and measured the activity (absence or presence) and intensity of vegetative phenophases. We used circular statistical analysis to assess differences between treatments. Our results revealed that leaf production was seasonal but relatively uniform for perennial species and highly seasonal (wet season) for annual species. Simulated dry years induced lower leaf emergence concentrated over a few months in annual species, but this effect was more strongly significant in one of the two perennial species. Both annual and perennial species can experience delayed and less intense leaf abscission during the rainy season in years with below-average precipitation. In contrast, large voluminous rains in years with above-average precipitation can accelerate and intensify the process of leaf renewal. If future precipitation reductions occur, the changes in phenological response indicate that the cover of annual and perennial herbaceous species in this study will likely decrease, altering the landscape and functioning of dry tropical forests. However, the potential trade-offs observed may help populations of these species to persist during years of severe drought in the Caatinga.


Assuntos
Florestas , Chuva , Estações do Ano , Brasil , Mudança Climática , Folhas de Planta/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Secas
4.
Neurosci Lett ; 837: 137903, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39025433

RESUMO

Lysergic acid diethylamide (LSD) is a synthetic psychedelic compound with potential therapeutic value for psychiatric disorders. This study aims to establish Caenorhabditis elegans as an in vivo model for examining LSD's effects on locomotor behavior. Our results demonstrate that LSD is absorbed by C. elegans and that the acute treatment reduces animal speed, similar to the role of endogenous serotonin. This response is mediated in part by the serotonergic receptors SER-1 and SER-4. Our findings highlight the potential of this nematode as a new experimental model in psychedelic research.

5.
Phys Rev Lett ; 132(23): 233001, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905671

RESUMO

Interatomic Coulombic decay (ICD) plays a crucial role in weakly bound complexes exposed to intense or high-energy radiation. So far, neutral or ionic atoms or molecules have been prepared in singly excited electron or hole states that can transfer energy to neighboring centers and cause ionization and radiation damage. Here we demonstrate that a doubly excited atom, despite its extremely short lifetime, can decay by ICD; evidenced by high-resolution photoelectron spectra of He nanodroplets excited to the 2s2p+ state. We find that ICD proceeds by relaxation into excited He^{*}He^{+} atom-pair states, in agreement with calculations. The ability of inducing ICD by resonant excitation far above the single-ionization threshold opens opportunities for controlling radiation damage to a high degree of element specificity and spectral selectivity.

6.
Aust Occup Ther J ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923569

RESUMO

INTRODUCTION: In childhood intervention, parent-therapist collaboration is central to the family-centred approach. Despite long-standing discussion in occupational therapy literature, the field faces challenges, including inconsistent terminology and difficulties in translating theory into practice. This paper represents the first part of a comprehensive scoping review study aimed at developing foundational concepts for collaborative practices with parents in occupational therapy for children. Therefore, this paper focusses on mapping existing practices, types, and approaches articulated in the literature. METHODS: We searched English-language sources published worldwide from 1998 to 2022 discussing collaborative practices with parents in occupational therapy for children aged 0-10 with any diagnosis, including multidisciplinary practices. Seven databases were searched. Data from peer-reviewed indexed literature, theses and dissertations, and book chapters were extracted and analysed through basic numerical and descriptive analyses before being synthesised into similar categories. The Joanna Briggs Institute Manual and the Preferred Reporting Items for Systematic reviews and Meta-Analysis-extension for Scoping Reviews were used. RESULTS: The scoping review yielded 299 papers. Parent-therapist collaboration was prominent in clinics, family homes, schools, and hospitals, particularly during therapy implementation, goal setting, and planning. Most reported practice types included 'interventions with parent engagement', 'parent-directed interventions', and 'parent education'. 'Family-centred', 'occupational-focussed', and 'client-therapist collaborative' approaches were frequently mentioned. There were inconsistencies in the terms used to describe collaborative practice characteristics. CONCLUSION: Over the past 24 years, the collaborative practice literature has expanded and evolved, with parent-therapist collaboration observed across various occupational therapy settings. Inconsistencies in this collaboration across different therapeutic stages were revealed, which could impact intervention success and sustainability. Further research is needed to explore parent-therapist collaboration mechanisms within and across stages. This scoping review also underscores the need for a common framework to guide practice and research. PLAIN LANGUAGE SUMMARY: This literature review explores how occupational therapists and parents work together in childhood intervention. Collaboration is essential for understanding and meeting children's needs within their family and community settings. However, occupational therapists and parents face challenges in applying family-centred practices and using a common language to bridge theory with practice. To address these challenges, we examined 299 papers published between 1998 and 2022 to understand how collaborative practices with parents have been described in the literature. Our review revealed that therapists and parents collaborate across various settings, such as clinics, schools, homes, and hospitals, mainly during therapy sessions, goal setting, and planning interventions. Collaborative practices take different forms. For instance, therapists often encourage parents to actively engage and take the lead in therapy, requiring therapists to recognise and respect parents' priorities and learning preferences. They often develop strategies together to support the child within family routines. While we found several studies on therapist-parent collaboration, the review outlined inconsistencies in how this practice was described and applied, which could affect its success. Therefore, more research is needed to understand the best ways in which collaboration can occur at each stage of therapy. The need for a core guideline for collaborative practice with parents in occupational therapy was also observed. While therapist-parent collaboration is used in occupational therapy for children, there is a clear need to minimise inconsistencies and gaps found in the literature, as well as to ensure a common language to promote intervention quality and success.

7.
Aust Occup Ther J ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923580

RESUMO

INTRODUCTION: In occupational therapy for children, collaborative practice with parents is crucial for meaningful family-centred interventions, yet it remains undefined and inconsistently addressed. This study aimed to establish foundational concepts for collaborative practice with parents in occupational therapy for children in progressing the field with a universal description. METHODS: This paper encompasses the second dataset of a larger scoping review and a preliminary validation of findings by an advisory panel. Data were gathered from indexed sources on collaborative practice with parents in occupational therapy for children (ages 0-10) using MedLine, PsychInfo, ERIC, Embase, OTSeeker, Scopus, and ProQuest Central. Data were extracted, charted, and descriptively analysed by paired independent reviewers. The Joanna Briggs Institute Manual and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis-extension for Scoping Reviews were used. A draft definition of collaborative practices, developed based on preliminary review findings and an operational definition, was validated by an advisory panel of 13 experienced Australian occupational therapists, whose input was integrated into a final, comprehensive description of collaborative practice. RESULTS: The scoping review encompassed 299 sources, revealing three major components of collaborative practice: 'collaborative practice aims', 'parent-therapist partnership', and 'strategies for collaboration'. The advisory panel endorsed the draft definition, confirmed its professional relevance, and suggested some modifications. CONCLUSION: The major outcome of this study is an evidence-based and discipline-specific preliminary description of collaborative practice with parents in occupational therapy for children. This description provides a common language and foundational concepts for the future development of a collaborative practice framework to guide practice and research. Future studies can explore specific components, exploring their mechanisms and significance. Further expanded validation is required, incorporating the perspectives of a wider community of occupational therapists and families to enhance the description's applicability.

8.
Anal Sci ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871978

RESUMO

The significance of accurate determination of ethanol content in hydrogel formulations was accentuated during COVID-19 pandemic coinciding with the heightened demand for sanitizing agents. The present article proposes three robust methodologies for this purpose: Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Densitometry with matrix effect correction by Near-Infrared Spectroscopy (NIR). All three methods demonstrated outstanding linearity (R2 ≥ 0.99) and minimal errors (< 1.7%), offering simplicity and operational efficiency. FTIR and Raman, being non-destructive and requiring minimal preparation, enable practical on-site analysis capabilities, underscoring the potential of the spectroscopic methods to expedite health investigations and inspections, empowering on-site ethanol determination, and relieving the burden on official laboratories. Additionally, the densitometry with NIR-based approach showcased superior accuracy and precision compared to spectroscopic methods, meeting validation criteria while offering operational advantages over the costly official distillation-based method. Therefore, it stands as a reliable and reproducible technique for comprehensive health and criminal compliance assessments, making it a compelling alternative for both industry and official laboratories.

9.
Syst Parasitol ; 101(4): 44, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839661

RESUMO

Species of Diolcogaster parasitize Lepidoptera pests of commercial plants. The diversity of this genus is high, but few species of Diolcogaster have been described. The description of a new Diolcogaster species provides information for the biological control using this insect. This study presents the description and key notes on the biology of a new Diolcogaster parasitoid wasp. This species was reared from a caterpillar of Hypercompe brasiliensis collected after feeding on a Gloxinia perennis plant important to floriculture. Two complementary identification analyzes were performed on Diolcogaster adult bodies. The first was the analyses of its external morphology and the second its molecular analysis (mitochondrial DNA). The morphological analysis defined the insect as a new species of Diolcogaster, named Diolcogaster joanesi sp. nov. A maximum-likelihood (ML) analysis partially confirmed the morphological analysis, placing D. joanesi within a cluster including a previously identified species (Diolcogaster choi) and seven other morphospecies. The proximity of D. joanesi to D. choi is discussed and an updated key for all New World species of the xanthaspis group is provided. Twenty-eight adult wasps were obtained (22 females and six males) out of 50 cocoons which larvae emerged from the caterpillar host. The findings contribute to the broader understanding of Diolcogaster in the Neotropics and its potential for the biological control of lepidopteran defoliators.


Assuntos
Controle Biológico de Vetores , Especificidade da Espécie , Vespas , Animais , Brasil , Vespas/classificação , Vespas/anatomia & histologia , Mariposas/parasitologia , Lepidópteros/parasitologia , Filogenia , Larva , Feminino
10.
Dalton Trans ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842058

RESUMO

Four new copper(II) complexes were synthesized and characterized with the general formula [Cu(N-N)(Th)(NO3)], where N-N corresponds to the N-heterocyclic ligands 1,10-phenanthroline (phen), 2,2'-bipyridine (bipy), 4,7-diphenyl-1,10-phenanthroline (dpp), and 4,4-dimethyl-2,2'-bipyridine (dmbp) and Th represents the N,N-dibenzyl-N'-benzoylthiourea. Cytotoxic activities of the complexes against HCT116 (human colon carcinoma), HepG2 (human hepatocellular carcinoma), and non-tumor MRC-5 (human lung fibroblast) cells were investigated. The copper(II) complexes 1-4 were characterized by spectroscopic techniques while complexes 1 and 2 were studied using single-crystal X-ray diffraction as well. The complexes possessed a five-coordinated structure with one nitrate ligand as a monodentate at the axial position and two bidentate ligands N-heterocyclic and N,N-dibenzyl-N'-benzoylthiourea. The complexes showed promising IC50 values, ranging from 0.3 to 9.0 µM. Furthermore, interaction studies with biomolecules such as calf thymus DNA (ct-DNA) and Bovine Serum Albumin (BSA), which can act as possible biological targets of the complexes, were carried out. The studies suggested that the compounds interact moderately with ct-DNA and BSA. Complexes 1, 2, and 4 did not lead to cell accumulation at any stage of the cell cycle but caused a significant increase in internucleosomal DNA fragmentation. Whereas, compound 3 caused cell cycle arrest in the S phase while doxorubicin caused cell cycle arrest in the G2/M phase. The effect of structural modifications on the metal compounds was correlated with their biological properties and it was concluded that an increase in biological activity occurred with increasing the extension of the diimine ligands. Thus, complex 3 was the most promising one.

11.
J Surg Oncol ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825982

RESUMO

BACKGROUND: Breast cancer (BC) is associated with a continuous increase in incidence, with high mortality rates in several countries. CD44, STAT3, and SOX2 are related to regulating of somatic cell division, tumorigenesis, and metastasis in BC. METHODS: A cross-sectional study was carried out at the Hospital de Cancer de Pernambuco (HCP) between 2017 and 2018. Fifty-one women with locally advanced (LA) and 14 with metastatic BC were included in the study. RESULTS: High CD44+/CD24neg and CD44+/CD24neg/SOX2+ levels in Luminal B (LB), HER2+, and triple-negative breast cancer (TNBC) compared with controls (p < 0.05). Low CD44+/CD24negSTAT3+ levels in LB, HER2+, and TNBC compared with controls (p < 0.05). High T lymphocytes, and low STAT3 + T, and SOX2 + T levels in BC patients (p < 0.05). High SOX2 + T levels in patients with axillary lymph node-negative (N0) compared with the axillary lymph node-positives (N1 and N2 groups; p < 0.05). High SOX2 + T levels in N1 compared to N2 (p < 0.05). High T lymphocytes and low SOX2 + T levels in the LA tumor compared to metastatic disease (p = 0.0007 and p = 0.02, respectively). High CD44 + /CD24negSTAT3+, and T lymphocyte levels in TNBC patients with LA tumor compared to metastatic (p < 0.05). Low STAT3 + T levels in TBNC patients with LA tumor compared to metastatic (p = 0.0266). CONCLUSION: SOX2 and STAT3 expression on circulating T lymphocytes and CD44 + /CD24neg cells in peripheral blood have prognostic roles in breast cancer. SOX2 and STAT3 expression are potential predictive biomarkers of disease progression in breast cancer regardless of tumor subtype.

12.
Methods Mol Biol ; 2775: 141-153, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758316

RESUMO

This chapter describes methodological details for preparing specimens of Cryptococcus neoformans (although it can be applied to any species of the genus) and their subsequent analysis by scanning and transmission electron microscopy. Adaptations to conventional protocols for better preservation of the sample, as well as to avoid artifacts, are presented. The protocols may be used to examine both the surface ultrastructure and the interior of this pathogenic fungus in detail.


Assuntos
Artefatos , Cryptococcus neoformans , Cryptococcus neoformans/ultraestrutura , Microscopia Eletrônica de Transmissão/métodos , Microscopia Eletrônica de Varredura/métodos , Manejo de Espécimes/métodos
14.
ACS Omega ; 9(20): 21904-21916, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799310

RESUMO

Doping nanoparticles represents a strategy for modulating the energy levels and surface states of nanocrystals (NCs), thereby enhancing their efficiency and mitigating toxicity. Thus, we herein focus on the successful synthesis of pure and gold (Au)-doped zinc oxide (ZnO) nanocrystals (NCs), investigating their physical-chemical properties and evaluating their applicability and toxicity through in vitro and in vivo assessments. The optical, structural, and photocatalytic characteristics of these NCs were scrutinized by using optical absorption (OA), X-ray diffraction (XRD), and methylene blue degradation, respectively. The formation and doping of the NCs were corroborated by the XRD and OA results. While the introduction of Au as a dopant did induce changes in the phase and size of ZnO, a high concentration of Au ions in ZnO led to a reduction in their photocatalytic activity. This demonstrated a restricted antibacterial efficacy against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Remarkably, Au-doped counterparts exhibited enhanced biocompatibility in comparison to ZnO, as evidenced in both in vitro (murine macrophage cells) and in vivo (Drosophila melanogaster) studies. Furthermore, confocal microscopy images showed a high luminescence of Au-doped ZnO NCs in vivo. Thus, this study underscores the potential of Au doping of ZnO NCs as a promising technique to enhance material properties and increase biocompatibility.

15.
Curr Top Med Chem ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38797894

RESUMO

INTRODUCTION: Zika virus (ZIKV) is a flavivirus transmitted through the bites of infected Aedes mosquitoes. These viruses can also be transmitted through sexual contact, vertical transmission, and possibly transfusion. Most cases are asymptomatic, but symptoms can include rash, conjunctivitis, fever, and arthralgia, which are characteristic of other arboviruses. Zika infection can lead to complications such as microcephaly, miscarriage, brain abnormalities, and Guillain-Barré syndrome (GBS). OBJECTIVE: The aim is to determine the inhibitory potential of the algae Kappaphycus alvarezii (K. alvarezii) on ZIKV replication. METHODOLOGY: Cytotoxicity experiments were performed using Vero cells to determine the CC50, and ZIKV replication inhibition assays (ATCC® VR-1839™) were conducted to determine the EC50. The mechanism of action was also studied to assess any synergistic effect with Ribavirin. RESULTS: K. alvarezii demonstrated low toxicity with a CC50 of 423 µg/mL and a potent effect on ZIKV replication with an EC50 of 0.65 µg/mL and a Selectivity Index (SI) of 651, indicating the extract's safety. Virucidal effect assays were carried out to evaluate the possible mechanism of action, and the compound addition time was studied, showing the potential to delay the treatment of infected cells by up to 6 hours. A potential synergistic effect was observed when K. alvarezii extract was combined with suboptimal concentrations of Ribavirin, resulting in 99% inhibition of viral replication. CONCLUSION: Our data demonstrate the significant potential of K. alvarezii extract and highlight the need for further studies to investigate its mechanism of action. We propose this extract as a potential anti-Zika compound.

16.
J Pediatr (Rio J) ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38734032

RESUMO

OBJECTIVE: To evaluate the association between inflammatory markers and abdominal fat assessed by ultrasound in prepubertal children with and without excess weight. METHODS: A cross-sectional study involving 241 prepubertal children, 156 with obesity, 37 with overweight, and 48 with normal weight, aged five to ten years, who were followed at a research unit on Childhood Obesity from a teaching hospital belonging to a public health system. The concentration of interleukin-6, tumor necrosis factor-α and C-reactive protein were assessed and regression analyses, considering outcome variables such as abdominal wall and intra-abdominal fat thickness measured by ultrasound, were performed. RESULTS: The findings highlighted an association between abdominal fat and inflammatory markers, even in children at this young age group. Subcutaneous fat showed a stronger association with inflammatory biomarkers compared to intra-abdominal fat when performing logistic regression, with a positive association between tumor necrosis factor-α and abdominal wall thickness equal to or greater than the 75th percentile in adjusted logistic regression (OR: 18.12; CI 95 %: 1.57: 209.55). CONCLUSIONS: Abdominal wall fat, in contrast to what is often observed in adults, appears to have a greater impact on chronic inflammation related to excessive weight in very young children.

18.
J Nat Prod ; 87(4): 1217-1221, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38630559

RESUMO

Two unusual naphthoquinones, named here as pleonotoquinones A (1) and B (2), were isolated along with two known anthraquinones (3 and 4) via chromatographic separations of an ethyl acetate extract of the roots of Pleonotoma jasminifolia. Compounds 1 and 2 are the first examples of quinones bearing a 2-methyloxepine moiety. The compounds were isolated with the aid of mass spectrometry and molecular networking, and their structures were resolved using 1D and 2D NMR and HRESIMS data. The isolated compounds were evaluated for their antiproliferative activity against human cancer cell lines, and compounds 1 and 2 displayed cytotoxicity against human colon cancer HCT116 cells (IC50 = 2.6 µM for compound 1 and IC50 = 4.3 µM for compound 2) and human liver cancer HepG2 cells (IC50 = 1.9 µM for compound 1 and IC50 = 6.4 µM for compound 2).


Assuntos
Antineoplásicos Fitogênicos , Ensaios de Seleção de Medicamentos Antitumorais , Naftoquinonas , Raízes de Plantas , Humanos , Naftoquinonas/farmacologia , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Estrutura Molecular , Raízes de Plantas/química , Células Hep G2 , Células HCT116 , Boraginaceae/química
19.
Sensors (Basel) ; 24(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38676159

RESUMO

The presence of green areas in urbanized cities is crucial to reduce the negative impacts of urbanization. However, these areas can influence the signal quality of IoT devices that use wireless communication, such as LoRa technology. Vegetation attenuates electromagnetic waves, interfering with the data transmission between IoT devices, resulting in the need for signal propagation modeling, which considers the effect of vegetation on its propagation. In this context, this research was conducted at the Federal University of Pará, using measurements in a wooded environment composed of the Pau-Mulato species, typical of the Amazon. Two machine learning-based propagation models, GRNN and MLPNN, were developed to consider the effect of Amazonian trees on propagation, analyzing different factors, such as the transmitter's height relative to the trunk, the beginning of foliage, and the middle of the tree canopy, as well as the LoRa spreading factor (SF) 12, and the co-polarization of the transmitter and receiver antennas. The proposed models demonstrated higher accuracy, achieving values of root mean square error (RMSE) of 3.86 dB and standard deviation (SD) of 3.8614 dB, respectively, compared to existing empirical models like CI, FI, Early ITU-R, COST235, Weissberger, and FITU-R. The significance of this study lies in its potential to boost wireless communications in wooded environments. Furthermore, this research contributes to enhancing more efficient and robust LoRa networks for applications in agriculture, environmental monitoring, and smart urban infrastructure.

20.
Heliyon ; 10(7): e27516, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560155

RESUMO

The importance of radiology in modern medicine is acknowledged for its non-invasive diagnostic capabilities, yet the manual formulation of unstructured medical reports poses time constraints and error risks. This study addresses the common limitation of Artificial Intelligence applications in medical image captioning, which typically focus on classification problems, lacking detailed information about the patient's condition. Despite advancements in AI-generated medical reports that incorporate descriptive details from X-ray images, which are essential for comprehensive reports, the challenge persists. The proposed solution involves a multimodal model utilizing Computer Vision for image representation and Natural Language Processing for textual report generation. A notable contribution is the innovative use of the Swin Transformer as the image encoder, enabling hierarchical mapping and enhanced model perception without a surge in parameters or computational costs. The model incorporates GPT-2 as the textual decoder, integrating cross-attention layers and bilingual training with datasets in Portuguese PT-BR and English. Promising results are noted in the proposed database with ROUGE-L 0.748, METEOR 0.741, and NIH CHEST X-ray with ROUGE-L 0.404 and METEOR 0.393.

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