Search Results (28)

Background and Objective: This study aimed to investigate the relationship between tramadol use and cardio electrophysiological imbalance (iCEB/iCEBc) in general surgery patients with complaints of acute postoperative pain (APP). Materials and Methods: In this prospective cross-sectional study, a total of 218 consecutive patients over the age of 18, who underwent surgical procedures in our clinic (postoperative), were included. For analgesic effect, tramadol was administered with an initial total max dose not exceeding 2 mg/kg. A single max dose (100 mg) was given intravenously, infused in 100 cc of saline over 60 min. In all patients requiring analgesia, electrocardiography (ECG) was performed in the supine position with 12 leads at 25 mm/s and 10 mm/mV, immediately before and after tramadol administration. iCEB was calculated as QT/QRS and iCEBc as QTc/QRS. Results: A total of 218 patients were included in this study, with 98 of them being male (45%) and the average age being 46.20 ± 17.19 years. The average tramadol dose for analgesic effect was 98.21 ± 7.62 mg. The QT interval (339.17 ± 36.27 vs. 349.88 ± 30.86, p = 0.001), QTc interval (407.07 ± 26.36 vs. 419.64 ± 31.78, p < 0.001), QRS duration (80.82 ± 11.39 vs. 78.57 ± 9.80, p = 0.018), iCEB (4.26 ± 0.69 vs. 4.52 ± 0.70, p < 0.001), and iCEBc (5.14 ± 0.86 vs. 5.42 ± 0.79, p = 0.001) values significantly increased compared to the baseline immediately after drug administration. Furthermore, the drug dose was identified as an independent predictor that increased iCEBc (β = 0.201, p = 0.003). Conclusions: Even at single and therapeutic doses, tramadol increases iCEB and iCEBc. Additionally, the drug dose is an independent predictor of increased iCEBc. Full article

E-mobility is progressively penetrating the European market with the ever-increasing registration of new battery electric vehicles (BEVs). Although BEVs can significantly contribute to achieving the goal of sustainable road transport, they pose new challenges related to the complexity of managing battery fire events, especially in confined spaces such as road tunnels. In this regard, while fires of BEVs with small-sized batteries (i.e., cars and vans) have been widely studied, the consequences of fires involving battery electric buses (BEBs), which are equipped with larger-capacity traction batteries, have not yet been sufficiently investigated. In this context, 3D computational fluid dynamics (CFD) simulations were performed to quantitatively assess the threat that a BEB might pose to the safety of users and rescue teams when it catches fire in a bi-directional road tunnel. In this respect, a comparison was also carried out with the consequences of the fire of a similar internal combustion engine bus (ICEB). Since the environmental conditions inside a tunnel, apart from its geometry, depend on both the traffic flow and type of ventilation, the safety of the users and rescue teams in the event of a BEB fire was evaluated by considering the tunnel under conditions of congested traffic, as well as natural or longitudinal mechanical ventilation. The results showed that the fire of the BEB, compared to that of its ICEB counterpart, worsened the environmental conditions inside the tunnel, especially in terms of toxic gas concentrations. This caused a reduction in the safety level of the users when considering the scenarios of both the naturally and mechanically ventilated tunnel. Moreover, in the case of natural ventilation, the BEB fire was found to cause a higher reduction in the safety level of the rescue teams. Full article

West Nile Virus (WNV) poses a significant global public health threat as a mosquito-borne pathogen. While laboratory mouse models have historically played a crucial role in understanding virus biology, recent research has focused on utilizing immunocompromised models to study arboviruses like dengue and Zika viruses, particularly their interactions with Aedes aegypti mosquitoes. However, there has been a shortage of suitable mouse models for investigating WNV and St. Louis encephalitis virus interactions with their primary vectors, Culex spp. mosquitoes. Here, we establish the AG129 mouse (IFN α/β/γ R^−/−) as an effective vertebrate model for examining mosquito–WNV interactions. Following intraperitoneal injection, AG129 mice exhibited transient viremia lasting several days, peaking on the second or third day post-infection, which is sufficient to infect Culex quinquefasciatus mosquitoes during a blood meal. We also observed WNV replication in the midgut and dissemination to other tissues, including the fat body, in infected mosquitoes. Notably, infectious virions were present in the saliva of a viremic AG129 mouse 16 days post-exposure, indicating successful transmission capacity. These findings highlight the utility of AG129 mice for studying vector competence and WNV–mosquito interactions. Full article

Immune response to biomaterials, which is intimately related to their surface properties, can produce chronic inflammation and fibrosis, leading to implant failure. This study investigated the development of magnetic nanoparticles coated with silica and incorporating the anti-inflammatory drug naproxen, aimed at multifunctional biomedical applications. The synthesized nanoparticles were characterized using various techniques that confirmed the presence of magnetite and the formation of a silica-rich bioactive glass (BG) layer. In vitro studies demonstrated that the nanoparticles exhibited bioactive properties, forming an apatite surface layer when immersed in simulated body fluid, and biocompatibility with bone cells, with good viability and alkaline phosphatase activity. Naproxen, either free or encapsulated, reduced nitric oxide production, an inflammatory marker, while the BG coating alone did not show anti-inflammatory effects in this study. Overall, the magnetic nanoparticles coated with BG and naproxen showed promise for biomedical applications, especially anti-inflammatory activity in macrophages and in the bone field, due to their biocompatibility, bioactivity, and osteogenic potential. Full article

Cancer is one of the deadliest diseases worldwide and has been responsible for millions of deaths. However, developing a satisfactory smart multifunctional material combining different strategies to kill cancer cells poses a challenge. This work aims at filling this gap by developing a composite material for cancer treatment through hyperthermia and drug release. With this purpose, magnetic nanoparticles were coated with a polymer matrix consisting of poly (L-co-D,L lactic acid-co-trimethylene carbonate) and a poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) triblock copolymer. High-resolution transmission electron microscopy and selected area electron diffraction confirmed magnetite to be the only iron oxide in the sample. Cytotoxicity and heat release assays on the hybrid nanoparticles were performed here for the first time. The heat induction results indicate that these new magnetic hybrid nanoparticles are capable of increasing the temperature by more than 5 °C, the minimal temperature rise required for being effectively used in hyperthermia treatments. The biocompatibility assays conducted under different concentrations, in the presence and in the absence of an external alternating current magnetic field, did not reveal any cytotoxicity. Therefore, the overall results indicate that the investigated hybrid nanoparticles have a great potential to be used as carrier systems for cancer treatment by hyperthermia. Full article

The spin-1/2 quantum transverse Ising model, defined on a ladder structure, with nearest-neighbor and four-spin interaction on a plaquette, was studied by using exact diagonalization on finite ladders together with finite-size-scaling procedures. The quantum phase transition between the ferromagnetic and paramagnetic phases has then been obtained by extrapolating the data to the thermodynamic limit. The critical transverse field decreases as the antiferromagnetic four-spin interaction increases and reaches a multicritical point. However, the exact diagonalization approach was not able to capture the essence of the dimer phase beyond the multicritical transition. Full article

Furfural is a platform molecule obtained from hemicellulosic monosaccharides present in lignocellulosic biomass. Due to the possibility of converting this molecule into several value-added chemicals and the need to search for more sustainable production processes, the present work aimed to produce and characterize different sulfonated activated carbons (AC-S) from sugarcane bagasse (SCB) for application in furfural production in aqueous media. ACs were produced by chemical activation using salts of ZnCl₂, NiCl₂, and CuCl₂ and a temperature and activation time of 550 °C and 3 h under nitrogen flow, respectively. Sulfonation was carried out with H₂SO₄ (98%) at a solid/liquid ratio of 1:10 at 160 °C for 2 h. Catalytic tests were performed using 5% catalyst mass regarding xylose, a temperature of 180 °C, and a reaction time of 2 h. ACs with high surface areas, ranging from 290 to 1100 m² g⁻¹, were produced. All catalysts had an increased sulfur content and total acidity after sulfonation, indicating the successful attachment of the sulfonic group (-SO₃H) in the carbon matrix of the CAs. The AC-S/CuCl₂ catalyst achieved the best catalytic performance compared to AC-S/ZnCl₂, AC-S/NiCl₂, and other acidic solids reported in the literature, achieving yield and selectivity of 55.96% and 83.93%, respectively. These results evidence the importance of the synergy between the Lewis and Brønsted acid sites on selective xylose dehydration and make AC-S/CuCl₂ a promising acid catalyst for converting xylose to furfural in an aqueous medium. Full article

This work describes a resonance Raman study performed in the domes of monolayer MoS₂ using 23 different laser excitation energies covering the visible and near-infrared (NIR) ranges. The multiple excitation results allowed us to investigate the exciton–phonon interactions of different phonons (A${}^{\prime }$₁, E${}^{\prime }$, and LA) with different excitonic optical transitions in biaxially strained monolayer MoS${}_2$. The analysis of the intensities of the two first-order peaks, A${}^{\prime }$₁ and E${}^{\prime }$, and the double-resonance 2LA Raman band as a function of the laser excitation furnished the values of the energies of the indirect exciton and the direct excitonic transitions in the strained MoS${}_2$ domes. It was noticed that the out-of-plane A${}^{\prime }$₁ phonon mode is significantly enhanced only by the indirect exciton I and the C exciton, whereas the in-plane E${}^{\prime }$ mode is only enhanced by the C exciton of the MoS₂ dome, thus revealing the weak interaction of these phonons with the A and B excitons in the strained MoS${}_2$ domes. On the other hand, the 2LA Raman band is significantly enhanced at the indirect exciton I and by the A (or B) exciton but not enhanced by the C exciton, thus showing that the LA edge phonons that participate in the double-resonance process in MoS${}_2$ have a weak interaction with the C exciton. Full article

Recent studies have argued that changes in fire regimes in the 21st century are posing a major threat to global biodiversity. In this scenario, incorporating species’ physiological, ecological, and evolutionary traits with their local fire exposure might facilitate accurate identification of species most at risk from fire. Here, we developed a framework for identifying the animal species most vulnerable to extinction from fire-induced stress in the Brazilian savanna. The proposed framework addresses vulnerability from two components: (1) exposure, which refers to the frequency, extent, and magnitude to which a system or species experiences fire, and (2) sensitivity, which reflects how much species are affected by fire. Sensitivity is based on biological, physiological, and behavioral traits that can influence animals’ mortality “during” and “after” fire. We generated a Fire Vulnerability Index (FVI) that can be used to group species into four categories, ranging from extremely vulnerable (highly sensible species in highly exposed areas), to least vulnerable (low-sensitivity species in less exposed areas). We highlight the urgent need to broaden fire vulnerability assessment methods and introduce a new approach considering biological traits that contribute significantly to a species’ sensitivity alongside regional/local fire exposure. Full article

The CO₂ reduction by solar means has been discussed as an alternative to emission abatement, a fundamental topic for sustainable, carbon-free production in the future. However, the choice of efficient systems, starting with the catalysts, is still a critical issue, especially due to the poor activity of available options. Polyoxometalates have been extensively studied as promising photocatalysts due to their semiconducting properties. Nevertheless, the synthetic conditions of polyoxoniobate are stringent due to the low reaction activity of Nb species, the lack of soluble precursors, and the narrow pH range. Unlike the literature, in the present study, we report a simple polyoxoniobate synthesis method. This synthesis method has some remarkable features, such as low processing time and temperature and good activity and selectivity in the CO₂ photoreduction process. The results revealed an outstanding efficiency for the CO₂ reduction reaction with a high selectivity of CO₂ to CO conversion (92.5%). Furthermore, C2 compounds (e.g., acetate) were produced in the liquid phase of the reaction system. Our findings are significant for indicating the potential of polyoxoniobate for CO₂ photoreduction, which opens a way to control competitive reactions with synthesis, leading to higher selectivity. Full article

Chagas disease is caused by the parasite protozoan Trypanosoma cruzi (T. cruzi) and affects millions of people in over 21 countries in around the world. The main forms of treatment of this disease, benznidazole and nifurtimox, present low cure rates in the chronic phase and often have serious side effects. Herein, we describe the evaluation of the trypanocidal activity of arylsulfonamides. The arylsulfonamides were evaluated in vitro against the amastigote and trypomastigote forms of the parasite. An enantiomerically pure example of arylsulfonamide was also tested. The initial results suggest that the arylsulfonamides evaluated act as DNA binding agents. A moderate activity was monitored against the intracellular forms of T. cruzi, with the best compound exhibiting an IC₅₀ value at 22 μM and a selectivity index of 120. However, the level of activity was not favorable for progressing towards in vivo studies for Chagas disease. Full article

In view of the GHG reduction targets to be met, Brazilian researchers are looking for cleaner alternatives to energy sources. These alternatives are primarily to be applied in the transport sector, which presents high energy consumption, as well as high CO₂ emissions. In this sense, this research developed an LCI study considering two bus alternatives for the city of Rio de Janeiro: diesel-powered internal combustion buses (ICEB) and a hydrogen-powered polymer fuel cell hybrid bus (FCHB). For the FCHB, three hydrogen production methods were also included: water electrolysis (WE), ethanol steam reforming (ESR) and natural gas steam reforming (NGSR). The research was aimed at estimating energy consumption, including the percentage of energy that is renewable, as well as CO₂ emissions. The results show diesel as the energy source with the highest emissions as well as the highest fossil energy consumption. Regarding the alternatives for hydrogen production, water electrolysis stood out with the lowest emissions. Full article

Plant extracts are complex mixtures that are difficult to characterize, and mass spectrometry is one of the main techniques currently used in dereplication processes. Fridericia chica is a species with medicinal uses in Latin American countries, used in the treatment of inflammatory and infectious diseases. Extracts of this plant species are characterized by the presence of anthocyanidins. In this study, using high-resolution mass spectrometry coupled with liquid chromatography, it was possible to determine the molecular formula of thirty-nine flavonoids. Fragmentation analysis, ultraviolet spectrum and nuclear magnetic resonance data allowed the partial characterization of the structures of these compounds. The spectral dataset allowed the identification of a series of flavones in addition to the desoxyanthocyanidins common in extracts of the species. The occurrence of some of the proposed structures is uncommon in extracts of species of the Bignoniaceae family, and they are reported for the first time in the extract of this species. Quantitative analyses of total flavonoids confirmed the high content of these constituents in the species, with 4.09 ± 0.34 mg/g of dry plant material. The extract under study showed low in vitro cytotoxicity with CC₅₀ ≥ 296.7 ± 1.4 µg/mL for Vero, LLC-MK2 and MRC-5 cell lines. In antiviral activity assays, inhibition of the cytopathic effects of Dengue, Zika and Mayaro viruses was observed, with EC₅₀ values ranging between 30.1 and 40.9 µg/mL. The best result was observed against the Mayaro virus, with an EC₅₀ of 30.1 µg/mL. Full article

The environmental impact due to the overexploitation of nonrenewable resources, the processing and transportation of materials, and waste production is a global concern that the construction industry must urgently address, since it is among the greatest contributors. Earth construction can be seen as an alternative building solution, enhancing sustainability, despite traditional techniques being nowadays in disuse in most developed countries. Construction with interlocking compressed earth blocks (iCEBs) is a recently developed technique, put in evidence in the last few decades, for overcoming many earth construction limitations. Here, this technique is studied as a sustainable building solution for Northern Portugal, where the typical soils are sandy, granitic residual soils with low clay content. These soils typically demand cement stabilization to produce earthen materials, which compromise the sustainability of the construction solution. In order to improve sustainability, stabilization with hydraulic lime is proposed as a partial replacement of cement. For this purpose, the properties of the selected soil were characterized through a set of geotechnical tests, with different percentages of cement and lime in the mixture composition tested, concerning the compressive strength of the specimens. A mixture composed of 87.5% of soil, 7.5% of cement, and 5% of lime was shown to be the most suitable for producing iCEBs with adequate mechanical performance. The compressive behavior of the iCEBs masonry was characterized by testing prisms and wallettes, considering both dry stack and mortar joints cases. The obtained results showed that using mortar in the bed joints allows for the improvement of the compressive strength (a 5%–18% increase) and Young’s modulus (a 65%–92% increase) of the masonry. Thus, it can be concluded that masonry built with locally produced iCEBs and stabilized with cement and lime is a feasible building solution, for a sustainable earth masonry built from sandy granitic residual soils, where the mechanical behavior is substantially enhanced by using bed-joint mortar. Full article