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Septic shock, a life-threatening condition, can result in cerebral dysfunction and heightened mortality rates. In these patients, disturbances in cerebral hemodynamics, as reflected by impairment of myogenic cerebral autoregulation (CA), metabolic regulation, expressed by critical closing pressure (CrCP) and reductions in intracranial compliance (ICC), can adversely impact septic shock outcomes. The general recommendation is to maintain a target mean arterial pressure (MAP) of 65 mmHg but the effect of different MAP targets on cerebral hemodynamics in these patients is not clear and optimal targets might be dependent on the status of CA. This protocol aims to assess the cerebral hemodynamics profile at different pressure targets in septic shock patients. Prospective, non-randomized, single-center trial, which will study cerebral hemodynamics in patients with septic shock within 48 hours of its onset. Patients will be studied at their baseline MAP and at three MAP targets (T1: 65, T2: 75, T3: 85 mmHg). Cerebral hemodynamics will be assessed by transcranial Doppler (TCD) and a skull micro-deformation sensor (B4C). Dynamic CA will be expressed by the autoregulation index (ARI), calculated by transfer function analysis, using fluctuations of MAP as input and corresponding oscillations in cerebral blood velocity (CBv). The instantaneous relationship between arterial blood pressure and CBv will be used to estimate CrCP and resistance-area product (RAP) for each cardiac cycle using the first harmonic method. The B4C will access ICC by intracranial pressure waveforms (P2/P1). The primary aim is to assess cerebral hemodynamics (ARI, CrCP, RAP, and P2/P1) at different targets of MAP in septic shock patients. Our secondary objective is to assess cerebral hemodynamics at 65mmHg (target recommended by guidelines). In addition, we will assess the correlation between markers of organ dysfunction (such as lactate levels, vasoactive drugs usage, SOFA score, and delirium) and CA. The results of this study may help to understand the effect of the recommended MAP and variations in blood pressure in patients with septic shock and impaired CA and ICC. Furthermore, the results can assist large trials in establishing new hypotheses about neurological management in this group of patients. Approval was obtained from the local Ethics Committee (28134720.1.0000.0048). It is anticipated that the results of this study will be presented at national and international conferences and will be published in peer-reviewed journals in 2024 and 2025. Trial registration number: NCT05833607. https://clinicaltrials.gov/study/NCT05833607.

Spent bleaching earths (SBEs) resulting from the refining of soybean oil contain significant amounts of residual oil and phosphorus, which pose an environmental and disposal problem. In this study, a sustainable biotechnological approach to reactivate SBEs through enzymatic hydrolysis with a commercial lipase under moderate conditions was investigated. In an initial 23 factorial experimental design, the effects of temperature (40–60 °C), enzyme amount (50–200 mg), and reaction time (4–8 h) were evaluated, with reaction time identified as statistically significant (p < 0.05). A second experimental design with lower enzyme concentrations (5–25 mg) validated a positive effect of enzyme dosage on phosphorus removal. This result was validated by a presence/absence test in which no phosphorus removal occurred in the absence of the biocatalyst. The best conditions (60 °C, 4 h, 5 mg enzyme) reduced the oil content from 10% to 5% and achieved 97% phosphorus removal. However, pigment removal efficiency was limited to approximately 34%, indicating partial restoration of the bleaching capacity compared to virgin earth. The enzymatic process also produced a nutrient-rich liquid hydrolysate containing Mg (16 mg/L), P (750 μg/L), and S (980 μg/L), suggesting potential use as a biofertilizer. Regenerated SBE demonstrated suitability for reuse in oil bleaching systems and potential applications in filtration and soil conditioning, providing a cost-effective and environmentally friendly alternative to conventional regeneration methods.

A series of catalysts consisting of gold nanoparticles supported on MnO2 presenting different morphologies were synthesized and tested in the base-free oxidation of furfural. Ultra-small Au particles (less than 3 nm) were deposited on low (commercial MnO2) and high (NF, nanoflowers and NW, nanowires MnO2) surface area supports. High activity was observed for Au/MnO2-NF material with very high selectivity to furoic acid. The X-ray photoelectron spectroscopy (XPS) study confirmed the presence of a significant amount of highly active Auδ+ species on the surface of the Au/MnO2-NF catalyst. These species seem to be responsible for the high activity in oxidation of furfural under mild conditions (air as oxidant, 110 °C).

A glassy carbon electrode was modified with a TiO 2 -gold nanoparticle hybrid integrated with multi-walled carbon nanotubes in a dihexadecylphosphate film (TiO 2 -Au NP-MWCNT-DHP/GCE) and applied to amperometric determination of ascorbic acid (AA). The modified sensor displays fast charge transfer and shows an irreversible anodic behavior for AA by cyclic voltammetry. Under optimal experimental conditions and using amperometry at 0.4 V, the analytical curve presented a statistical linear concentration range for AA from 5.0 to 51 μmol L −1 , with a limit of detection of 1.2 μmol L −1 . The electrode was successfully applied to the determination of AA in pharmaceutical and fruit juice without the need for major pretreatment of samples. Graphical abstract Schematic of a new sensing platform for ascorbic acid (AA). It is based on a glassy carbon electrode (GCE) modified with TiO 2 -Au nanoparticles integrated into carbon nanotubes in a dihexadecylphosphate film. The sensor was applied to amperometric determination of AA in juice and pharmaceutical samples.

Simultaneous bilateral total hip arthroplasty (SimBTHA) offers benefits such as reduced hospital stay and costs for patients with bilateral hip disease. However, the optimal surgical approach remains uncertain. This study aimed to compare the perioperative outcomes of SimBTHA performed via the direct anterior approach (DAA) versus the posterior approach (PA). A systematic review and meta-analysis were conducted, including studies reporting outcomes of SimBTHA using DAA and PA. The primary outcome was the incidence of allogeneic blood transfusions, while secondary outcomes included blood loss and surgical complications, such as dislocations, periprosthetic fractures, and infections. Six studies were included, analyzing 944 patients, with 372 undergoing SimBTHA via DAA and 572 via PA. No significant difference was observed in the number of allogeneic blood transfusions between the two approaches (RR = 1.04; 95% CI: 0.76 to 1.43; p=0.63). DAA was associated with significantly lower blood loss compared to PA (MD = -31.51 mL; 95% CI: -43.07 to -19.94 mL; p=0.07). However, there was no significant difference in the rates of surgical complications between the two groups (RR = 0.63; 95% CI: 0.32 to 1.26; p=0.12). While DAA showed a benefit in reducing blood loss, it did not demonstrate superiority over PA regarding transfusion rates or surgical complications. These findings highlight the need for further randomized controlled trials with standardized methodologies and longer follow-up periods to better assess the optimal approach for SimBTHA.

A glassy carbon electrode was modified with a TiO.sub.2-gold nanoparticle hybrid integrated with multi-walled carbon nanotubes in a dihexadecylphosphate film (TiO.sub.2-Au NP-MWCNT-DHP/GCE) and applied to amperometric determination of ascorbic acid (AA). The modified sensor displays fast charge transfer and shows an irreversible anodic behavior for AA by cyclic voltammetry. Under optimal experimental conditions and using amperometry at 0.4 V, the analytical curve presented a statistical linear concentration range for AA from 5.0 to 51 [mu]mol L.sup.-1, with a limit of detection of 1.2 [mu]mol L.sup.-1. The electrode was successfully applied to the determination of AA in pharmaceutical and fruit juice without the need for major pretreatment of samples.

A glassy carbon electrode was modified with a TiO -gold nanoparticle hybrid integrated with multi-walled carbon nanotubes in a dihexadecylphosphate film (TiO -Au NP-MWCNT-DHP/GCE) and applied to amperometric determination of ascorbic acid (AA). The modified sensor displays fast charge transfer and shows an irreversible anodic behavior for AA by cyclic voltammetry. Under optimal experimental conditions and using amperometry at 0.4 V, the analytical curve presented a statistical linear concentration range for AA from 5.0 to 51 μmol L , with a limit of detection of 1.2 μmol L . The electrode was successfully applied to the determination of AA in pharmaceutical and fruit juice without the need for major pretreatment of samples. Graphical abstract Schematic of a new sensing platform for ascorbic acid (AA). It is based on a glassy carbon electrode (GCE) modified with TiO -Au nanoparticles integrated into carbon nanotubes in a dihexadecylphosphate film. The sensor was applied to amperometric determination of AA in juice and pharmaceutical samples.

In the first part of my dissertation, I developed two approaches for selectively probing the SERS activities of individual hot spots, i.e., experimentally detect the SERS signals only for the molecules that are trapped within the hot-spot region in individual Ag nanoparticle dimers. Then, I performed a systematic investigation on the SERS activity of individual dimers composed of two closed spaced Ag nanoparticles. By utilizing Ag nanoparticles displaying a variety of well-defined shapes, sizes and orientations to construct the dimers, I were able to precisely correlate the detected SERS signals to the specific geometry of individual hot spots. In the second part of this dissertation, I performed a systematic investigation on the galvanic replacement reaction between PtCl62- and Pd nanocrystals with well-defined shapes including octahedra, nanocubes, and nanorods. The resultant hollow Pd-Pt bimetallic nanostructures were employed as electrocatalysts for the oxygen reduction reaction (ORR). Our results demonstrated that the nanostructures derived from Pd octahedra displayed the highest ORR activity, being 1.7 times more active based on equivalent Pt mass than the commercial Pt/C. I also conducted a mechanistic study on the galvanic replacement reaction between AuCl4- and Pd nanorods. Differently from the Pd-Pt system, a new type of hybrid nanostructure in the tadpole shape consisting of a Au head and a Pd tail was obtained due to a localized galvanic replacement mechanism. As an extension of my work to develop new electrocatalysts for the ORR, a templateengaged reaction was utilized for the synthesis of RuSe2+δ nanotubes. The RuSe2+δ nanotubes were active towards the ORR and displayed no loss in activity in the presence of methanol, as opposed to commercial Pt/C. Finally, the template-engaged reaction was applied to the synthesis of Se@MSe (M = Zn, Cd or Pb) colloidal spheres having similar sizes but different compositions. They were utilized as building blocks to obtain 3D photonic crystals via self-assembly. Moreover, superparagametic properties could be obtained via the incorporation of Fe3O4 nanoparticles into the a-Se cores. Taken together, this represents a versatile approach to the synthesis of magnetoactive spheres with similar dimensions but a variety of compositions and properties.

Bacterial adaptation is accelerated by the acquisition of novel traits through horizontal gene transfer, but the integration of these genes affects genome organization. We found that transferred genes are concentrated in only ~1% of the chromosomal regions (hotspots) in 80 bacterial species. This concentration increases with genome size and with the rate of transfer. Hotspots diversify by rapid gene turnover; their chromosomal distribution depends on local contexts (neighboring core genes), and content in mobile genetic elements. Hotspots concentrate most changes in gene repertoires, reduce the trade-off between genome diversification and organization, and should be treasure troves of strain-specific adaptive genes. Most mobile genetic elements and antibiotic resistance genes are in hotspots, but many hotspots lack recognizable mobile genetic elements and exhibit frequent homologous recombination at flanking core genes. Overrepresentation of hotspots with fewer mobile genetic elements in naturally transformable bacteria suggests that homologous recombination and horizontal gene transfer are tightly linked in genome evolution. Horizontal gene transfer (HGT) is an important mechanism for genome evolution and adaptation in bacteria. Here, Oliveira and colleagues find HGT hotspots comprising  ~ 1% of the chromosomal regions in 80 bacterial species.

Self-transmissible mobile genetic elements drive horizontal gene transfer between prokaryotes. Some of these elements integrate in the chromosome, whereas others replicate autonomously as plasmids. Recent works showed the existence of few differences, and occasional interconversion, between the two types of elements. Here, we enquired on why evolutionary processes have maintained the two types of mobile genetic elements by comparing integrative and conjugative elements (ICE) with extrachromosomal ones (conjugative plasmids) of the highly abundant MPFT conjugative type. We observed that plasmids encode more replicases, partition systems, and antibiotic resistance genes, whereas ICEs encode more integrases and metabolism-associated genes. ICEs and plasmids have similar average sizes, but plasmids are much more variable, have more DNA repeats, and exchange genes more frequently. On the other hand, we found that ICEs are more frequently transferred between distant taxa. We propose a model where the different genetic plasticity and amplitude of host range between elements explain the co-occurrence of integrative and extrachromosomal elements in microbial populations. In particular, the conversion from ICE to plasmid allows ICE to be more plastic, while the conversion from plasmid to ICE allows the expansion of the element’s host range.