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Introduction: Transcatheter endovascular aortic repair (TEVAR) has revolutionized the management of thoracic aortic pathologies, providing a less invasive alternative to conventional surgical methods. Since January 2024, a newly standardized single-branched TEVAR has been introduced into the commercial market, reducing costs and expediting implantation for thoracic aortic aneurysms and dissections. Anatomical eligibility remains crucial, limiting its utilization in Spain, with only one prior case documented. Case Presentation: A 66-year-old man with dyslipidemia was incidentally diagnosed with a chronic Stanford B Aortic Dissection during a urinary tract infection follow-up. The dissection extended from the distal descending aorta to both iliac arteries, accompanied by significant thoracic segment aneurysmatic degeneration with a large entry tear. Notably, the patient exhibited a fetal configuration of supraaortic vessels with the left carotid artery and brachiocephalic artery arising from a common trunk, ensuring a 3.5cm safety margin for endoprosthesis placement. All visceral branches originated from the dissection's true lumen. Procedure and Anesthetic Management: The procedure involved a zone 2 TEVAR procedure with a thoracic branch endoprosthesis to the left subclavian artery, along with a second endoprosthesis in the distal descending aorta. General anesthesia with neuromonitoring by BIS /DSA (Medtronic) and SvcO2 by NIRSS was performed. Unfortunately, intraoperative neuromonitoring with motor- and sensitive-evoked potentials is not available for Vascular Surgery at present time in our center. A dual surgical approach involving brachial and femoral insertion sites was necessitated, while Transesophageal echocardiography (TEE) was used to facilitate guidewire insertion within the true lumen of the dissection. Intraoperatively, the patient maintained hemodynamic stability, necessitating low-dose noradrenaline to uphold a MAP of 80-85 mmHg. A transient and mild hypotensive episode occurred during the deployment of the endoprosthesis, which was managed without the need for aortic ballooning due to the secure attachment to the aortic wall. Following confirmation of proper placement, a reduction in blood flow within the false lumen was observed via TEE, progressing to early thrombosis. Anticoagulation was diligently maintained with an activated clotting time (ACT) ranging between 250-280 throughout the procedure. The patient remained under observation in the surgical intensive care unit (ICU) for 24 hours, during which hemodynamic stability was sustained with a MAP ranging between 75-80 mmHg without the need for vasopressor support, and neurological function remained unaltered. Endovascular repair has emerged as the preferred approach for descending aortic aneurysms due to its associated benefits. Nevertheless, the intricacy inherent in these procedures presents challenges for anesthetic management, necessitating scrupulous attention to hemodynamic parameters, coagulation equilibrium, and neurological surveillance. The advent of sophisticated and standardized endoprostheses has facilitated expedited treatment timelines in carefully selected patients. In our specific case, the utilization of such prostheses proved efficacious, culminating in the successful closure of the entry point of the dissection. The dynamic evolution in endovascular aortic interventions underscores the imperative for adept anesthetic teams capable of navigating the complexities inherent in these procedures. Such significant challenges in perioperative patient care mandate the presence of a multidisciplinary Aortic Team in high-complexity centers for optimal management. [ABSTRACT FROM AUTHOR]

Purpose The purpose of our study was to evaluate effective ischemia and its associated complications using the limb occlusion pressure technique versus standard pneumatic ischemia technique. Design Single-centered randomized, controlled clinical trial. Methods One hundred sixty participants were randomized into two equal and parallel groups: (1) intervention group—LOP technique, and (2) control group—standard pneumatic ischemia technique. Findings Anesthetic incidences (need to administer analgesics for pain and/or hypnotics for anxiety) were similar in both groups. Statistically significant differences were observed for pain, hyperemia, and hospitalization, with higher values in the control group. Patients in the intervention group had, at 95% confidence, a 2.9 times greater chance of having optimal ischemia (assessed as 9 on the analog scale) than patients in the control group (odds ratio, 2.9; 95% confidence interval, 1.4 to 6.1). Conclusions Intervention group patients had lower indexes of hyperemia, pain, and hospital stay. [ABSTRACT FROM AUTHOR]

This contribution provides a case example on the generation of large-scale recumbent folds in syn-orogenic granitoids. We analyze the progressive reworking of extension-related structures into later ones after a period of crustal thickening. The Padrón migmatitic dome formed after the climax of the Gondwana-Laurussia collision in the late Paleozoic. Petrostructural analysis carried out in the eastern flank of this dome reveals that extensional flow resulted in progressive exhumation of mainland Gondwana, which rested under peri-gondwanan allochthonous terranes and a suture zone during maximum crustal thickening. Exhumation proceeded up to upper crust levels (andalusite stability field) along with partial melting of the middle-lower crust and with the generation of granitoid laccoliths during an early extensional stage. Newly-formed lithological and mechanical anisotropies, such as the presence of variably-sized sheet-shaped bodies of syn-orogenic granitoids, provided a favorable rheological setting for fold nucleation during the intermediate stages of extension. In extending orogenic crust, whether recumbent folds occur after significant melt production depends on the lateral/vertical flow ratio, and on the orientation of deforming bodies with regard to kinematic/strain axes. We suggest that subhorizontal extensional flow dominated over vertical flow during the early and intermediate stages of the evolution of the Padrón dome. A component of vertical (diapiric) flow caused progressive tilting of the sheet-like bodies and obliquity respect to strain axes. This resulted in the development of regional-scale folds at the expense of syn-orogenic granitoids, such as in the case of the Portomouro recumbent synform. Extensional ductile flow was oblique to the trend of the orogen during the whole process, and directed to the NNW during the formation of recumbent folds. Non-coaxial shearing favored an (NNW-SSE) elongate shape for the syn-kinematic granitic massifs as well as the subsequent nucleation of recumbent folds. Deformation concentrated along discrete detachments during the late stages of extension. [ABSTRACT FROM AUTHOR]

Solar selective paints, with the addition of Co 3 O 4 as a pigment, are used to improve energetic efficiency in solar collectors. Although Co 3 O 4 has been obtained by different methods, references about combustion synthesis are scarce. Co 3 O 4 powders have been synthesized by stoichiometric and non-stoichiometric routes using aspartic acid (Asp) or tri-hydroxi-methyl-aminomethane (Tris) as fuels. The samples were calcined in air at 500 °C. They were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectrum and the specific surface area of the samples was determined by means of the Brunauer–Emmett–Teller technique. The optical properties of pigments were assessed by means of a spectrophotometer. In all cases, powders exhibited the crystalline structure of Co 3 O 4 . A minimum crystallite average size of 29 nm was observed for powders obtained by the “stoichiometric/Asp” combustion route, while a maximum value of 41 nm was stated for powders obtained by the “non-stoichiometric/Asp” combustion process. The average particle size ranged between 50 and 100 nm. The powders obtained by the“stoichiometric/Asp” method were selected to study their optical properties; their solar absorption value was 86%. Solar selective surfaces composed by Co 3 O 4 pigments and an alkyd resin were obtained and applied over copper or aluminum substrates. In both cases, solar absorptance was of 93% and comparable with similar solar selective surfaces, but the thermal emittance value was higher than 90%, as a consequence of the large width of the films. [ABSTRACT FROM AUTHOR]

Summary: Objective: To describe the epidemiological profile of NI in the PICU and NICU, and its related risk factors. Design: A prospective surveillance study from May through October 2000 was performed in the PICU and NICU in a tertiary care university hospital in Barcelona. Results: During the study period, 257 patients were admitted to the PICU and 121 to the NICU. The incidence rate of NI was 26.5 infections per 100 admissions and 1.7 infections per 100 patient-days in the PICU. In the NICU, the incidence rate of NI was 74.3 infections per 100 admissions and 2.7 infections per 100 patient-days. Bacteraemia was the most frequent episode of NI in both units. The most common microorganisms isolated were Gram-positive bacteria (47.2% and 72.7%) in each unit. The factors more frequently associated with NI in the PICU were as follows: patient age under 1 year (RR 5.0; 95% CI 1.6–15.4), class IV of CCS (RR 3.7; 95% CI 1.2–11.1), and mechanical ventilation (RR 2.5; 95% CI 1.0–6.0). In the NICU, the most significant predisposing factors were birth weight less than 1000g (RR 2.8; 95% CI 1.0–8.0), umbilical arterial catheterization (RR 5.7; 95% CI 1.1–28.5) and parenteral nutrition (RR 2.4; 95% CI 1.2–4.6). The hospital stay was higher in infected patients than in non-infected patients (p <0.001). Conclusions: This study describes the epidemiological profile of NI in two high-risk paediatric units. These results suggest the need to evaluate the infection control measures with the aim of reducing associated morbidity. [Copyright &y& Elsevier]

Abstract: Different amounts of a one-component polyurethane prepolymer base primer was applied to avoid roughening of a bovine tanned leather, and to improve adhesion and mechanical properties. Polyurethane prepolymer reacted with collagen fibers of the leather, creating urea moieties during curing. The penetration of the primer and cohesion of the leather were increased by increasing the amount of primer applied. Application of primer improved the thermal, rheological, mechanical and adhesion properties of the leather, and the time that the primer needed to cure increased by increasing the amount of primer. Adhesion obtained in joints produced with primed leather is higher than that obtained with roughened leather. [Copyright &y& Elsevier]

Abstract: Two solutions in ethyl acetate (EA) containing 3wt% trichloroisocyanuric acid (TCI) from two different suppliers having different active chlorine contents were used as chemical surface treatment of a vulcanized styrene–butadiene (SBR) rubber. The amount of active chlorine in the TCI solutions was evaluated by iodine titration. The changes produced in the SBR rubber were monitored by using ATR-IR spectroscopy, scanning electron microscopy and contact angle measurements. The adhesive strength variation in SBR rubber/polyurethane adhesive joints was consistent with the variation in surface chemistry, wettability, and topography of the treated SBR rubber. The increase in time between TCI solutions preparation and SBR treatment allowed an increase in adhesive strength, the highest value corresponded to the joint produced with the SBR rubber treated with TCI solution prepared for 60 days. On the other hand, the active chlorine concentration in the TCI solutions was not the only parameter determining the adhesion of SBR rubber, as the highest adhesive strength was not achieved by treating the rubber with the TCI solution with higher active chlorine content. Therefore, the effectiveness of the halogenation treatment of rubber was not always higher by using a halogenating solution with higher active chlorine content. Furthermore, the chlorine concentration in the TCI solutions was not stable in the course of time, 60 days after preparation of solutions was the most efficient chlorinating solution for SBR rubber surface modification. [ABSTRACT FROM AUTHOR]

Abstract: Waterborne polyurethane adhesives are an interesting alternative to the current solvent-borne polyurethane adhesives used in the industry. Different aliphatic waterborne polyurethane dispersions (PUDs) with different solids content were synthesised by reacting isophorone diisocyanate (IPDI) with a polycarbonate derived from hexanediol via the acetone method. The PUDs were characterised by Brookfield viscosity, pH, particle size, transmission electron microscopy (TEM) and solids content measurement. The dry polyurethane films were characterised by ATR-IR spectroscopy, plate–plate rheology, differential scanning calorimetry (DSC) and thermal gravimetry (TGA). Their adhesion was evaluated from T-peel tests of flexible PVC/waterborne polyurethane dispersion/flexible PVC joints and single lap-shear tests of aluminium/waterborne polyurethane dispersion/aluminium joints. The PUDs showed bimodal particle size distribution. The mean particle size of the PUDs decreased by increasing their solids content but the particle size distribution of the PUDs increased by decreasing their solids content. As the solids content increased the Brookfield viscosity of the PUDs increased due to lower mean particle size where particle crowding was favoured, the PUD having 44wt% solids content was an exception (higher particle size but lower polydispersity). On the other hand, the increase in the solids content increased the hard segments content and the degree of phase separation of the polyurethanes. The greater the solids content of the polyurethanes, the lower their glass transition temperatures values and the lower the elastic moduli. Adhesive strength under peel stresses were not affected by the solids content in the polyurethanes but the single lap-shear strength values decreased by increasing the solid contents in the polyurethanes due to lower hard segments content. [Copyright &y& Elsevier]

Abstract: Three nanosilicas with different particle sizes were added to a polyurethane adhesive (PU). The filled adhesives were characterized by thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA), transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and contact angle measurements. Adhesive strength was evaluated from single lap shear test of solvent wiped stainless steel/polyurethane adhesive joints. Addition of nanosilica filler altered the degree of phase separation between the hard and soft segments in the polyurethane, in different extent depending on the nanosilica particle size. Furthermore, upon curing higher degree of crosslinking was obtained in the nanosilica filled polyurethane. The nanosilicas agglomerated into the polyurethane matrix. On the other hand, the addition of nanosilica increased the surface energy of the polyurethane to a greater extent by increasing the nanosilica particle size and moderate increase in the single lap shear strength of stainless steel/polyurethane adhesive joints was obtained. [Copyright &y& Elsevier]

Abstract: Waterborne polyurethane dispersions (PUDs), with possible use as adhesives, derived from polycarbonate diols (PCDs) were evaluated. The influence of the NCO/OH ratio and particle size distribution on the properties of both the aqueous dispersions and dry films were evaluated. The polydispersity of the PUD was increased by increasing its hard segments content. On the other hand, the properties of the PUDs depended on both the NCO/OH ratio and the polydispersity. As the NCO/OH ratio increased, the Brookfield viscosity of the PUDs decreased due to broader particle size distribution. On the other hand, an increase in the NCO/OH ratio decreased the crystallinity of the polyurethane films. Furthermore, the greater the polydispersity the higher the urea hard segment content, the higher the glass transition temperature value and the higher the elastic modulus of the polyurethanes. [Copyright &y& Elsevier]

Abstract: Thermoplastic polyurethane (TPU) adhesives containing nanosilicas with different specific surface area and silanol group content were prepared and characterized by FTIR spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TGA), X-ray diffraction, plate-plate rheology, dynamical–mechanical–thermal analysis (DMTA), transmission electron microscopy (TEM), and strain–stress test. Adhesive strength was obtained from T-peel tests of PVC/polyurethane adhesive joints. Formation of agglomerates of nanosilica particles within the polyurethane matrix were favoured by increasing the silanol content likely due to stronger hydrogen bond interactions between the silanol groups on the nanosilica over those between the polyurethane and the nanosilica. As a consequence, inter-urethane bonds formation rather than ester-urethane bonds were favoured, leaving the soft segment chains more free to interact between them. Thus, addition of nanosilica favoured the phase segregation in the thermoplastic polyurethane. The increase in specific surface area and silanol content in the nanosilica, generally enhanced the degree of phase separation in the polyurethane, being less marked for nanosilicas with more than 200m2/g and 0.60mmol SiOH/gsilica. On the other hand, the addition of the nanosilica improved the tensile strength and elongation at break, and the viscoelastic properties of the polyurethane. The immediate adhesive strength of PVC/polyurethane adhesive joints increased in the filled adhesives and it was determined by the rheological properties of the polyurethane–nanosilica mixtures. By increasing the time after joint formation, the crystallization of the polyurethane was produced giving higher adhesive strength and although a cohesive failure in the PVC was always obtained, a slight though progressive increase in joint strength was found with the passage of time with the ordering of the three systems (PU-0.45, PU-0.60 and PU-0.90) remaining unchanged with the PU-0.60 system the stronger and the PU-0.90 system the weaker. This is in agreement with the trends in the viscoelastic and mechanical properties of the filled adhesives. [Copyright &y& Elsevier]

Abstract: Waterborne polyurethane adhesives are an interesting alternative to the current solvent-based polyurethane adhesives used in footwear industry. In this study, different aqueous polyurethane dispersions were prepared by using the prepolymer mixing process. The ionic groups content in the polyurethane ionomer structure was varied by changing the amount (5 and 8wt% (with respect to the prepolymer weight) of the internal emulsifier—dimethylolpropionic acid (DMPA). The decrease in the DMPA content slightly increased the particle size in number due to the decrease in both the hydrophilicity of the polyurethane ionomer, and the electrolytic stability of the aqueous polyurethane dispersion. Furthermore, the lower the DMPA amount, the lower the hard segment content in the ionomer and the higher the crystallinity of the polyurethane; however, the resistance to flow under temperature (i.e. thermoplasticity) was reduced. The resistance to thermal degradation of the polyurethane ionomer increased by decreasing the DMPA content due to the lower hard segment content. Finally, high initial adhesive strength was obtained and the adhesion to PVC increased as the DMPA content in the polyurethane ionomer decreased. [Copyright &y& Elsevier]

Phosphatidylinositol 4,5-bisphosphate (PIP 2) acts as substrate and unmodified ligand for Gq-protein-coupled receptor signalling in vascular smooth muscle cells (VSMCs) that is central for initiating contractility. The present work investigated how PIP 2 might perform these two potentially conflicting roles by studying the effect of myristoylated alanine-rich C kinase substrate (MARCKS), a PIP 2 -binding protein, on vascular contractility in rat and mouse mesenteric arteries. Using wire myography, MANS peptide (MANS), a MARCKS inhibitor, produced robust contractions with a pharmacological profile suggesting a predominantly role for L-type (CaV1.2) voltage-gated Ca2+ channels (VGCC). Knockdown of MARCKS using morpholino oligonucleotides reduced contractions induced by MANS and stimulation of α 1 -adrenoceptors and thromboxane receptors with methoxamine (MO) and U46619 respectively. Immunocytochemistry and proximity ligation assays demonstrated that MARCKS and CaV1.2 proteins co-localise at the plasma membrane in unstimulated tissue, and that MANS and MO reduced these interactions and induced translocation of MARCKS from the plasma membrane to the cytosol. Dot-blots revealed greater PIP 2 binding to MARCKS than CaV1.2 in unstimulated tissue, with this binding profile reversed following stimulation by MANS and MO. MANS evoked an increase in peak amplitude and shifted the activation curve to more negative membrane potentials of whole-cell voltage-gated Ca2+ currents, which were prevented by depleting PIP 2 levels with wortmannin. This present study indicates for the first time that MARCKS is important regulating vascular contractility and suggests that disinhibition of MARCKS by MANS or vasoconstrictors may induce contraction through releasing PIP 2 into the local environment where it increases voltage-gated Ca2+ channel activity. Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract: In México, uncontrolled landfills or open-dumps are regularly used as “sanitary landfills”. Interactions between landfills/open-dumps and shallow unconfined aquifers have been widely documented. Therefore, evidence showing the occurrence of aquifer contamination may encourage Mexican decision makers to enforce environmental regulations. Traditional methods such as chemical analysis of groundwater, hydrological descriptions, and geophysical studies including vertical electrical sounding (VES) and ground penetrating radar (GPR) were used for the identification and delineation of a contaminant plume in a shallow aquifer. The Guadalupe Victoria landfill located in Mexicali is used as a model study site. This landfill has a shallow aquifer of approximately 1m deep and constituted by silty sandy soil that may favor the transport of landfill leachate. Geophysical studies show a landfill leachate contaminant plume that extends for 20 and 40m from the SE and NW edges of the landfill, respectively. However, the zone of the leachate’s influence stretches for approximately 80m on both sides of the landfill. Geochemical data corroborates the effects of landfill leachate on groundwater. [Copyright &y& Elsevier]